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Money and Shopping ESL – Ka-Ching Shania Twain – English with Songs I’ve wanted to create a presentation of the lesson plan based on the song “Ka-ching” for a while, since I often use it to add some more fun to the topic of shopping and money. It’s a good source of money vocabulary, as well as ideas for discussion. That’s how I’d use it in class: 1. Brainstorm adjectives and verbs that collocate with the word “money”. Teach some new words, if necessary. 2. Tell the students that they’re going to listen to a song called “Ka-Ching”. Ask them to think what might be the connection between the word “ka-ching” and money. (Ka-ching is an imitation of the sound made by a cash register, used when someone’s action will result in money) 3. Make sure they are familiar with some of the words from the song (Slides 2 – 4) 4. Ask them to find the rhyming words (Slide 5) 5. Listen to the song and fill in the gaps (almost all the missing words are rhymes, so it should be quite easy to hear them and remember in case some of them are new to the learners) 6. Discuss the message of the song and then move to a general discussion about money and shopping (slide 10) I hope you enjoyed the lesson. I’ll be happy to read your comments! I'm an English teacher from Russia passionate about learning and teaching foreign languages. I speak English, German, Russian and Hebrew and I'm learning Spanish and Chinese. I've been teaching English online for 5 years. I love meeting people and sharing experiences. Here's moreabout me.
The peripheral nervous system can suffer damage, such as a brachial plexus injury. What is the Peripheral Nervous System? Peripheral nerves are also known as the peripheral nervous system, which contains “43 pairs of motor and sensory nerves” that make a connection between the central nervous system (brain and spinal cord) and the rest of the body. The peripheral nervous system is in charge of motor coordination, movement, and sensation. The following nerves are part of the peripheral nervous system: ulnar, tibial, sciatic, spinal accessory, radial, median, femoral, lateral femoral cutaneous, common peroneal, and brachial plexus.1 Peripheral Nerve Injuries Because the peripheral nerves are complicated and fragile, they are easily injured. Some patients may have surgical interventions recommended to them. The types of trauma that can affect the peripheral nerves include tumors, entrapments and compressions (e.g., carpal tunnel syndrome), and injuries (e.g., brachial plexus injury).2 The brachial plexus nerves conduct the signals between the spinal cord and the hand, arm, shoulder, and chest. The nerves “originate in the fifth, sixth, seventh and eighth cervical (C5-C8), and first thoracic (T1) spinal nerves”. Inflammation, tumors, and trauma to the shoulder may trigger brachial plexus injuries. Sometimes they are caused by childbirth, and these brachial plexus injuries are known as “obstetric”. Others are considered “traumatic”, caused by falls or “direct violence or gunshot wounds, by violent traction on the arm, or by efforts at reducing a dislocation of the shoulder joint”.3 Brachial Plexus Injuries (BPIs) could also be caused by motorcycle accidents, blunt trauma, inflammation, compression, or neuropathies. BPIs fall into the following types: neuroma (tumor), neurotemesis (nerve is divided), axonotemesis (axons are severed), neurapraxia (nerve is compressed or stretched), rupture (nerve is torn), and avulsions (nerve is “pulled out from the spinal cord”). It depends on the injury if treatment is possible. Loss of sensation, muscle weakness, pain, and even paralysis are signs of a possible BPI.4 Some peripheral nerve injuries may heal on their own, and patients can seek rehabilitation. Others may require surgery.5 Contact sports might cause minor damage, such as “stingers”, where the BPI feels “like an electric shock or burning sensation” or leads to weakness or numbness in the arm. More serious injuries include symptoms such as severe pain, inability to use certain muscles, and lack of sensation. If the symptoms are recurrent or severe, it is important to seek treatment, as BPIs “can cause permanent weakness or disability”.6 Proper diagnosis is necessary in order to treat brachial plexus and other peripheral nerve injuries. Depending on the severity of the situation, if surgery is not warranted, chiropractic and massage can help some patients who seek an alternative to medications. Some patients have had their pain managed by electrical stimulation (TENS). After the initial trauma, patients can be advised by their chiropractor about exercises to increase range of motion. Hydrotherapy, massage, and chiropractic care can provide pain relief during rehabilitation. With proper treatment, some patients may move from a “flail arm” (little movement) situation to complete recovery. Healthcare providers can also give advice on how to avoid future injury.7 Learn about rotator cuff injuries and treatments.
The Essential Elements of Culture Joel Dubois, (c) 2009, 2013-14—for free, fully cited distribution only I(a). Two Types of Dynamic Culture To begin with, consider formal definitions of culture. Observers generally use the word "culture" in two different ways, as reflected in dictionary definitions of the term. For example, Webster's Dictionary defines culture as, on the one hand, the "enlightenment and excellence of taste acquired by intellectual and aesthetic training." This definition alludes to the frequent use of "culture" to highlight what is most noteworthy in the art, literature, music and philosophy of a given society, typically by those situated within it. Some refer to this as "high" culture, or "Culture" with a capital "C." Even though religion is often a primary force in shaping "high" culture, especially in Asia, those whose primary interest is a culture's art, literature, music or philosophy are typically less interested in religion in and of itself. On the other hand, Webster's also points out that the same term may denote "the integrated pattern of knowledge, belief, and behavior that depends upon...learning and transmitting knowledge to succeeding generations," which may also be described as "the customary beliefs, social forms, and materials traits of a racial, religious or social group." These definitions allude the fact that those studying a particular society, who are often situated outside of it, typically view all of that society's products, not simply its most refined, as important for understanding it. Some refer to this as "low" culture--not because it is UNrefined, but because it encompasses the entire foundation of a society's "high" culture. Because religion has been and remains a primary motivator of human activity in most cultures, especially in Asia, understanding religion is key to analyzing the broader elements of a culture. This course certainly features examples of the "high" culture of late medieval and modern Asia. But in to order make sense of such examples, the course also places significant emphasis on the broader elements of Asian culture, because most students are largely unfamiliar with them. Interestingly, many students taking the course today do trace their ancestry back to Asia, perhaps even in their parent's generation, and so have been directly exposed to Asian culture. Even those students, however, have typcially grown up studying other cultures through the the public school medium of English. Despite sincere efforts to diversify curriculum, such schooling still focuses primarily on the history and products of European and North American cultures. This course therefore assumes no background in the study of Asian culture, and thus attempts to orient students to its basic elements. The fact that the word "culture" means different things also hints at another important point: culture is dynamic rather than static. This may seem obvious, but a closer look at the difference between static and dynamic systems drives home how important the distinction really is. A static system is one in which all parts relate to one another in a consistent and predictable way. Machines made by human beings are for the most part like this: every part of an engine must consistently do its job in a prescribed way in relation to every other part in order for the system that is that engine to be considered functional. There are also social systems that function this way: when we wait in line at a ticket or checkout counter, we expect each person to wait their turn, not to disturb others in the line, and any behavior that deviates from this detracts from the functioning of the system. While some static systems are as simple as a pulley or unicycle, some can be highly complex: consider airliners, space stations and computers. Dynamic systems, on the other hand, are by nature complex for two reasons. First, they include a large number of elements that can in practice never be completely separated and studied; and secondly, the relationship of those elements to one another is continually evolving. Most living things are like this: although scientists of the past several centuries thought they could study living systems and physical laws as one would a machine, contemporary investigators are increasingly admitting that every attempt to do so has proven inadequate so far. Likewise much of human behavior--including the cultures that it produces--is highly dynamic, and social scientists now likewise admit that viewing the human mind using a static framework always falls short. The division between static and dynamic systems, furthermore, is not hard and fast. Experienced engineers know that the static system of most machines, when studied closely enough, are acted on by dynamic forces. An investigator of culture, then, must be open to encountering a bewildering diversity of messy variables that cannot be reduced to neat formulas, as well as phenomena that cannot be predicted based on static theories. This dynamic nature of culture is also an important reason for the team-based learning format of the course: such dynamic approaches are much more effective at preparing investigative consultants for the real-life complexity of culture than static, instructional methods of learning that focus on transfering facts from teacher to student.
The world is losing its honey bees at an alarming rate - a trend that could prove disastrous for us all.... In the closing months of 2006, when thousands of American beehives were found to be almost entirely devoid of bees ñ victims of a mysterious malady known as Colony Collapse Disorder (CCD). A study across 15 different states of the USA by the Apiary Inspectors of America found that from September 2006 to March 2007, almost a third of all honey bee colonies had collapsed. This winter it was even worse, with a recode 36% of colonies lost between September and March. Nor is the problem limited to America: large numbers of colonies have been wiped out in Canada, South America, Asia and Europe. In Croatia, five million bees were reported to have disappeared in 48 hours; in Taiwan last year around ten million vanished. CCD occurs when most of the bees suddenly disappear from a hive ñ leaving it like an apian Mary Celeste ñ with only queens, eggs or pupae (the "brood") and a few immature workers still remaining. The vanished bees ñ strangely never found ñ are thought to die singly far from home. The phenomenon is odd for various reasons. First, bees never usually abandon a hive until the brood has hatched; their sophisticated in-built navigation system allows them to forage up to three miles from the hive and return safely. Second, when a colony dies, the honey left behind is usually raided by bees from other hives, or by moths and beetles. Yet bees and pests avoid the abandoned hives like the plague. And lastly, the incidence of CCD is very erratic. Some beekeepers report heavy losses while their neighbours maintain healthy hives. If honey bee populations continue to decline it will, of course, hit honey supplies. But far more disturbing is the effect it could have on plant. Most flowering plants rely on animals to pollinate them, and the honey bee is nature's premier pollinator, with a body perfectly designed to collect and spread pollen, and a work ethic to match: one big colony, containing up to 60,000 worker bees can pollinate millions of flowers in a day. The US Department of Agriculture estimates that about a third of the food we eat benefits directly or indirectly from bee pollination. Scientists remain puzzled. One study at Pennsylvania State University found that a microbe ñ the Israeli Acute Paralysis Virus, which immobilises bees and kills them ñ was present in all but one of the sick colonies. But researchers believe the virus, along with other diseases found in "collapsed" colonies, may be a symptom rather than the cause. Given the variety of associated diseases, it seems likely there has been widespread damage to the bees' immune system. Various explanations are advanced. In America, hives are hauled around the country to pollinate crops, and one theory is that the bees' immune systems get damaged in the process. Another sees the cause in the disruptive effects of climate change, while others again trace it to one of two well-known bee diseases: the varroa mite, a virulent blood parasite; or Nosema ceranae, a pathogenic gut fungus. (More fancifully, some even blame mobile phones, which are said to interfere with with bees' navigation systems.) The impact of all such factors (except the last) is exacerbated by the shrinking size of the gene pool ñ most bee keepers having filled their apiaries with just one type of bee from Italy, renowned for its honey and gentleness. But many beekeepers point the finger at a quite different culprit: pesticides. Again, it's not quite clear. However, Dave Hackenberg, the US beekeeper widely credited with discovering CCD, thinks that his bees started to abandon their hives after they had been exposed to apple trees sprayed with a new breed of pesticide: a neonicotinoid, an artificial form of nicotine that attacks insects' nervous systems and disorientates them. One such insecticide has been banned in France since the 1990s, when it was blamed for heavy winter bee deaths. However, deaths have not noticeably decreased since then. Far from it. The first such recorded case was in America 150 years ago, and ever since, large numbers have vanished at intervals throughout North America, Europe and Australia. An epidemic first reported in the Isle of Wight in 1904 wiped out 90% of the UK's honey bee colonies. These losses have been given many different names: disappearing disease, spring dwindle, May disease, or autumn collapse. What really bothers scientists and beekeepers about the current situation, though, is the fact that it comes on the back of a sustained reduction in bee numbers, resulting from disease, urbanisation, and beekeepers retiring or going out of business. In America, there were 5.9 million maintained colonies in 1947; today there are only 2.44 million; feral honey bees have all but died out. If bees keep disappearing at this rate, it's estimated that there will be none left in the US by 2035. As in America, beekeeping has taken a nosedive (from 360,000 hives in 1947 to 250,000 today). Officially, CCD hasn't yet hit Britain; but the varroa mite has caused much damage since it arrived in 1992, and there have been reports of suspected CCD cases. This spring, more than 25% of colonies were found dead, compared to 18.2% last year. The environment ministry (Defra) has stepped up investigations, but the British Beekeepers' Association fears not nearly enough is being invested in research. "If the bee disappeared off the surface of the globe," Albert Einstein is reputed to have said, "then man would only have four years of life left." This may be an exaggeration, but as Alison Benjamin and Brian McCallum explain in their recent book A World Without Bees, if the honey bee did disappear, agriculture as we know it would collapse. More than 90 commercial crops ñ from apples, peaches and citrus fruits to strawberries and blackberries, to nuts, carrots, broccoli and onions ñ are pollinated by bees. So is cotton and much livestock fodder, such as clover and alfalfa. A study by Cornell University found that bees helped produce $60bn of food around the world - $15bn in the US alone, where many commercial beekeepers take their hives on a five-month tour of the country, pollinating California's lucrative almond trees, for instance, then Florida's citrus trees and Maine's blueberries. Defra estimates that Britain's 250,000 hives contribute £165m to agricultural output. Without bees, wind-pollinated grasses would continue to grow, but flowers and vegetable beds would be devastated, and there would be far less food for birds and mammals to eat. In southern Sichuan in China, where honey bees were wiped out by insecticides, pear trees have to be pollinated by hand - an immensely labour intensive business. Article provided by Pest Control Charter
What is Environmental Justice? Environmental justice pertains to the worthy and fair treatment of all humanity irrespective of color, income, place of origin, or race in connection to the advancement, adoption, and observance of environmental regulations, laws and policies. In other words, the terminology is based on the broader definitions of the environment and its surroundings with respect to the conditions which a person lives. Environmental organizations such as EPA have environmental justice as one of their goals so as to protect all people or communities from any sort of environmental harms within their operational areas. The primary aim of environmental justice is therefore to ensure each and every person benefits from equal degree of protection from environmental and health hazards. At the same time, it also ensures everyone has the same degree of access to decision-making process to have an environment with healthy living, working and learning conditions. Broadly, environmental justice is all about equal distribution of the benefits and risks of the environment accompanied with participatory decision-making on environmental matters. Principles of Environmental Justice Environmental justice is a social movement that originated from the need to ensure healthy environments for all communities regardless of color, income, place of origin, or race. For this reason, 17 principles of environmental justice were drafted and adopted by delegates to the first National People of Color Environment Leadership summit held on October 1991 in Washington DC. Since, these principles have served as the cornerstone for environmental justice. The following are the 17 principles according to the document drafted and adopted in the 1991 summit. - Environmental Justice asserts that mother earth is sacred, that everything on earth is connected ecologically and is interdependent, and that every species has a right to freedom from ecological destruction. - Environmental Justice requires all public policies to be founded on justice and mutual respect for all people without any bias or discrimination. - Environmental justice advocates for the right to use land and renewable resources responsibly, ethically and in a way that is balanced in pursuit of a sustainable planet for humanity and other living organisms. - Environmental justice asks for universal protection from indiscriminate nuclear testing, the production and discarding of toxic waste and toxins and testing of nuclear material that threaten the very important right to clear the air, water, land and food. - Environmental justice confirms the elementary right to economic, cultural, political and environmental volition of every person. - Environmental justice calls for a stop to production of toxic wastes and radioactive substances, and that the past and present producers should be accountable for the people, the detoxification and management of hazardous wastes at the production point. - Environmental justice appeals for the right to participation as equal partners at every decision that needs to be made with regards to their environmental surrounding, including assessment of needs from assessments, planning, implementation and enforcement. - Environmental justice confirms every workers right to a healthy and safe working environment without having to choose between unemployment and an unsafe source of livelihood. It also confirms that those who work from home have a right to freedom from environmental hazards. - Environmental justice protects the rights of those who fall victim to environmental injustice to receive reparations and full compensation for damages they incur and also receive great health care. - Environmental justice considers any acts of environmental injustice by the government a violation of international laws; the United Nations Convention on Genocide and the Universal Declaration on Human Rights. - Environmental justice has to recognize a national and legal relationship between the regional natives and the government through agreements, compacts, treaties and covenants that affirm self determination and sovereignty. - Environmental justice confirms the urban and rural ecological policies needs to clear and reconstruct urban and rural areas to be in balance with Mother Nature, respecting and recognizing the cultural integrity of communities and providing equal access to all available resources. - Environmental justice appeals for enforcement of the principles of informed consent and a stop to testing of experimenting of medical and reproductive procedures and products and vaccines on people of color. - Environmental justice argues against the operations that are destructive carried out by multinational corporations. - Environmental justice disapproves of occupation, exploitation and repression of land, people and their different cultures and other forms of life by the military. - Environmental justice asks for empowerment of current and future generations that addresses social and environmental issues based on current experience and appreciation for the different cultural perspectives. - Environmental justice requires that we make our choices both personally and as consumers to consume as little as we can of the earth’s resources and produce as little waste as we can. We have to make the decision to reprioritize and challenge our lifestyles in order to ensure a healthy world for the current and future generations. Importance of Environmental Justice It defines human relationship with the environment The human relationship with the environment revolves around perception and value and the role that these two play in our behavior and lives. One thing that shapes our values is justice. It drives and shapes us into being who we are. Most people recoil against injustice towards other humans and other species of living organisms. Those who are empowered on environmental injustice understand that it protects humanity and other lives by protecting the environment. Thus, they condemn environmental pollution which can harm communities, individuals and ecosystems. People also value outcomes they see as just. When people realize that environmental justice protects environmental elements and commons that belong to their community, they support it. When people realize this, they protect current and future generations by being empowered through environmental justice initiatives. It highlights the importance of conservation and fair usage of natural resources People get to conserve natural resources when they follow environmental justice. Given that communities debate over justice when it comes to distributing available resources like water fairly, it ensures the resources are used wisely. For instance, unfair distribution and usage of natural resources can be dangerous especially in areas where they are scarce. Environmental justice therefore emphasizes on fair distribution and opposes wastage. When the principles of environmental justice are followed, injustices associated with natural resources are forgotten and things like wars and clashes over usage of natural resources are forgotten. Sustainability can only be well comprehended through environmental justice Sustainability revolves a lot around the indefinite time renewable resources can be harvested while pollution reduces and humanity can stop being overly dependent on non renewable resources. Justice is about which rights are owed to what or who and assigning the right treatments appropriate to behavior and circumstance. According to Wolfgang Sachs and Tilman Santarius have noted in their book, Fair Future, everyone should be accountable according to their needs and rights. When we weigh the benefits of environmental justice such as natural resources and burdens such as pollution, responsibility is learned and solutions to attain sustainability are taken. Sure sustainability might be in a distant future but the actions we take in the present through environmental justice initiatives take us a step toward it. It defines the need for just distribution of resources (distributive justice) Because it is not wrong for one person to have more resources than others, distributive justice is not about equally sharing resources. Just distribution of resources revolves around how the people involved are involved with one another. Justice applies not when one has more resources that another, but if one person takes resources from another person’s environment. It also applies when one has more resources than they need while another is suffering for lacking any, this is injustice. Environmental justice thus emphasizes on the law of distribution. It strengthens environmental laws, policies, and regulations Justice falls under two categories; procedural justice which revolves around how policies are decided on and consequentialist justice which is what comes off those decisions and actions. For procedural justice, the rights of people have to be respected in making decisions. Since it redistributes benefits and burdens, environmental justice supports the policies about the environment. The principles of environmental justice support and strengthen environmental laws through equal distribution of resources and laws regarding pollution. Examples of Environmental Justice The following are examples of environmental justice over the years and cases where environmental justice was applied. According to Ejolt, only about thirty five percent of cases on environmental justice cases reach any sort of conclusion compared to seventeen percent of the global cases. As these numbers suggest, in most cases justice is not exactly served but in some cases, environmental justice is followed. 1972, Pittston coal The case by workers against the Pittston coal company is one of the successful environmental cases. It was after the workers strike following Pittson Company terminating health care benefits for retirees, widows and miners who are disabled and the displacement of thousands of people causing an environmental nightmare of epic proportions. The company’s sludge bi-products flowed from uphill creating sludge dams that were ignored by the company. In February 1972 however, the dams gave way and ended up displacing so many people by turning the ground to marsh. It is for these reasons that legal action was taken against Pittston Coal Company to settle the people. Federal and state resources are still being used in attempt to fix all the land there. 1989, Exxon Valdez disaster This is one of the most known environmental disasters and cases where environmental justice applied. An oil tanker, Exxon Valdex, containing thirty eight gallons of crude oil ran aground. This was at a Prince William Bligh reef which is offshore Alaska. It killed marine life for thousands of miles within the ocean and it continued for many years thereafter. Exxon Oil Company paid millions in fines and litigation in addition to taking care of cleaning up. 1993, Chevron Refining In 1993, Chevron refining company wanted to expand its operations to Richmond in Carlifornia. There was much opposition due to concerns for the health of the locals and environmental pollution, Chevron ignored these and still went ahead with operations. Citizens however formed a coalition called the county toxics coalition. The coalitions formed a judicial pact with Chevron refining company that allowed chevron to continue operations as long as they provided a five million dollar grant funding the city’s future environmental programs. The coalition is effective to this day. BP is an oil company that is known and operates internationally. In 2010 however, they caused the worst disaster ecologically speaking yet. While BP was pumping oil from the gulf of Mexico at the ocean floor, the rig exploded resulting in a rupture of the highly pressurized pipeline fill of oil. Millions of gallons of oil spilled and since there was no known way to stop the spillage, there was massive leakage. The well head was eventually capped but the damage was done. Marine life was killed, ecological and even human fatalities were found. Despite the lawsuits, levies and clean up funds, the damages are still suffered up to date. Anew technology called fracking is highly booming in the United States. It pumps highly pressurized liquids to create fissures on the shale rock from which oil and natural gases can escape. Its advocates had managed to ease the storm around fracking but a recent study by researchers from Duke Universities have stirred it up by presenting facts about the ecological impact of fracking. Facts show environmental pollution and direct impact on human lives around the areas of mining. Litigations and lawsuits are now gearing up, some successful while some still ongoing. Image credit: pixabay Latest posts by Rinkesh (see all) - Top 11 Best Solar Powered Chargers of 2018 - May 18, 2018 - Top 11 Best Solar Powered Water Pumps of 2018 - May 16, 2018 - 15+ Excellent Reasons to Join the Tiny House Living Movement - May 13, 2018
Presentation on theme: "Kingdom Animalia: Sponges & Cnidarians Learning Target Objectives (I can …): List characteristics of animals (especially invertebrates), including their."— Presentation transcript: Kingdom Animalia: Sponges & Cnidarians Learning Target Objectives (I can …): List characteristics of animals (especially invertebrates), including their type of symmetry. Distinguish between the 3 germ layers and the structures that develop from them. Differentiate between and describe sponge and cnidarian structures (anatomy) and physiology (function). Compare and contrast sexual and asexual reproduction in both sponges and cnidarians. Give examples of polyp and medusa body forms. Kingdom Animalia -all heterotrophic - all multicellular - all have a similar embryonic period - all eukaryotic - no cell walls ______ ______ ______ ______ ______ ______ ______ ______ ______ Invertebrates = animals with NO backbone ( % of all animals are invertebrates.) Some of these are identified by shape (including symmetry). Symmetry – how body parts are arranged around a point or central axis Types of Symmetry: 1) spherical symmetry – ball shaped (may be hollow). Any plane passing through the center makes similar halves. 2) bilateral symmetry – can be divided in half along 1 line/plane making each half appear the mirror image of the other. 3) radial symmetry – any plane through its central axis makes mirror image halves. Ex: cylinders - most common in animals the don’t move around much or at all Ex: hydra Bilaterally symmetrical animals have: Anterior end – front end or “head” end Posterior end – hind end or “rear” end Dorsal surface – top of upper surface Ventral surface – bottom surface When nerve tissue and sensory organs are concentrated at the anterior end, it’s called cephalization. Most multicellular organisms have a germ layer which develops & specializes into 3 layers: 1) ectoderm – becomes the outer body covering 2) mesoderm – middle layer, may form inner body linings (mesentery) and muscles 3) endoderm – innermost layer, forms the gut lining Phylum Porifera (pore bearer) – Sponges - pores = holes - once (sometimes still) used as sponges - sessile – attach themselves to a surface and don’t move (don’t relocate). Much like a plant. This means food has to come to the sponge. - aquatic (live in water) Sponge Structure & Function: - hollow, sac-like body closed at the bottom - osculum – fairly large opening at the top of the body - have ectoderm (pinnacoderm) & endoderm and a jellylike substance (mesoglea) which sometimes contains spicules (spikes) for support & protection - No true mesoderm - collar cells (choanocytes) with flagella These collar cells line the inside of the body tube. Their movement draws water & food particles through the small pores, into the central chamber, and out the osculum. Food is filtered out by the collar cells. This is called filter feeding. Sponges eat mostly bacteria, small algae, and protozoans. Amebocytes – cells that move like an ameba while carrying food particles to and waste particles away from other body cells. (Wastes leave through the osculum.) Spongin – hard substance that gives sponges a simple skeleton for support. This is what remains after the sponge dies. This is what was used as a “sponge” in homes. Porifera (Sponge) Reproduction Asexual: Budding – small growths, “buds,” begin and break off into new sponges. Gemmules – special “buds” of food filled amoebocytes that can survive in harsh environments that may kill the adult sponge. (Dormant stage) Regeneration – the re-growth of an organism or of its parts into a complete organism. (Each piece of a cut up sponge can re-grow.) Sexual: Sperm enters the pores and is carried by the amoebocytes to an egg. This forms an immature larva form with flagella so it can swim to a new location, attach to something, and mature. Some sponges are hermaphrodites, that means they produce BOTH eggs & sperm. This does NOT mean they can be self-fertile! Phylum Cnidaria: - all live in water, most in salt water - characterized by cnidocytes, (stinging cells) - coelenterates (have a hollow gut) - also have tentacles Some examples include: sea anemones, corals, jellyfish, hydra Cnidarian Body Forms: Polyp – vase shaped, sessile (doesn’t move), attach to rocks, etc., mouth points upward. Medusa – free-swimming, umbrella shape, mouth points downward Cnidarian Body Structure: A) 2 tissue layers: 1) endoderm – inner layer 2) ectoderm – outer layer (The mesoglea – is a jellylike material between the 2 tissue layers) B) tentacles – long, arm-like structures with coiled stingers inside the cnidocytes (which kill large prey) The tentacles draw food into the mouth. Waste materials also exit through the mouth. * All cnidarians have tentacles surrounding their mouth. * Cnidarians have radial symmetry. 3 Classes of Cnidarians: 1) Scyphozoa – spend most of life cycle as medusae (Ex: jellyfish) 2) Anthozoa – live only as polyps (Ex: anemones & coral) 3) Hydrozoa – include organisms that are either medusae or polyps or alternate between the two ) Class Scyphozoa: “cup animals” - medusa is dominant form - jellyfish - nematocysts (coiled stingers) within cnidocytes may contain deadly poison (Ex: “sea wasp” jellyfish off Australia’s coast) Jellyfish Reproduction: Sexual reproduction occurs in the medusa form. Male jellyfish release sperm and females release eggs into the water. Fertilization results in a planula that anchors to the seafloor, etc. (after a short “swim” using cilia). This becomes a polyp which asexually buds into stacks of medusae which soon separate and become free swimming. (Medusa reproduces sexually. Polyp reproduces asexually.) 2) Class Anthozoa: “flower animals” - polyp form - includes sea anemones and corals - basal disks attach polyps to rocks, etc. Coral: - live in huge colonies of small polyps - produce calcium shells that cement together. These remain behind and form a base for more coral after the polyp dies. - only live in warm, shallow water - have symbiotic relationship with algae. Algae lives in coral cells providing oxygen to coral. Anemone: - no shells - eat fish, etc. - symbiotic relationship with clown fish - larger than coral polyps 3) Class Hydrozoa: - polyps that can move by: a) releasing bubbles at the basal disk & then floating off, or by b) bending end over end in somersaults. - have a nerve net located in the mesoglea Hydra Reproduction: - usually asexual “budding” in warm weather - sexual reproduction in cold, fall weather. Eggs and sperm are produced by meiosis in ovaries and testes. The zygote forms a hard cover that protects it Until spring when it develops into a polyp. - some are hermaphroditic (both male & Female reproductive structures)
Clines are gradients that are used for teaching and learning shades of meaning. Words are spaced along the gradient. For example, in English we use a range of words to describe temperature, for example tepid, hot, boiling, cool, cold, warm, chilling, and freezing. After modelling the task, these words can be given to groups of students to place on the cline from the highest to the lowest temperature. The discussion that comes with this task is as important as the task itself. Published on: 28 May 2009
\|The active vision head is composed by four video cameras (two at each eye), and actuated by motors at each joint. The head designed currently is an initial prototype model. The system includes a neck and two eyes. The neck has three D.O.F. actuated joints, with three revolute joint motors corresponding to three torques. The eyes have a common actuated revolute joint (a tilt joint) and independent pan actuated joints (one for each eye). The two cameras at each eye rotate with same pan and tilt angles. Initial Prototype Model of the Active Vision Head Each eye has two cameras to simulate human's vision the top cameras are B/W high resolution cameras, that acquire a image within a small range of view; and the two lower cameras are color low resolution cameras that acquire images within a large range. The basic eye movements made by awake, frontal eyed, foveal animals are: saccades, smooth pursuit, vergence, physiological nystigmus, vestibulo ocular reflex - also known as vestibular nystigmus - and opto kinetic nystigmus: Drawing of the Vision Head The robotic body where the head is mounted is a four-legged robot. When walking or running for executing a desired task, this body will introduce translation as well as rotation movements on the base of the stereo head. If the eyes are gazing to a target, these movements will move the fixation point away from the target. The goal is then to move the robotic head to maintain the fixation point on the target. Accelerometers and gyroscopes will be used as inertial sensors to measure these movements. Knowing that the movement of the base of the head relative to the target is a relative movement, the problem can be reformulated as the target being moving relative to the head, assuming that it is possible to measure the target movement (for example, using visual processing). This way, the algorithm used to stabilize the vision head using inertial sensors is precisely the same used to follow the target when the latter is moving. Furthermore, the same algorithm will be explored to perform different behaviors, such as approaching to a target and performing movements around it. Inertial sensors will be mounted on the head to measure body motions. This head will have three rate gyroscopes (to measure angular velocity) mounted on orthogonal axes (corresponding to the semicircular canals) and three linear accelerometers which measure linear accelerations - (corresponding to the otolith organs). Linear velocity is obtained by integrating linear accelerations and linear and angular positions are obtained by integrating the correspondent velocities. This technique provides good results for transient and rapid head motions. However, it has two drawbacks: with the integration of the measurements, the system tends to accumulate drift, and the scaling constant for the integration must be selected empirically. Encoders are used to measure rotations of the neck and eyes joints. One encoder is placed attached to the shaft of each revolute joint motor, to measure angular velocity. Angular position is obtained integrating the velocity measurements. The problem of stabilization consists of compensating body movements by moving the head so that the target is always on the foveal image viewed from the eyes. With the goal of stabilizing images acquired in real-time (frame-rate of 30 frames per second), the stabilization procedure must be executed at least twice as fast as the visual frame-rate. The movements of the robotic head must resemble movements of a human (or other animal) like head. Therefore, instead of moving first the eyes to compensate for body motions, and then moving the neck along the direction defined by the cyclope eye of the head and the target, it is preferred to move neck and eyes simultaneously. This has two main advantages: maximizes the range of possible motions for the next movement, giving simultaneously to the robot a more life-like appearance. Working Model 3D simulations for the Head model A Genetic Algorithm was implemented to solve for the 3 extra degrees of freedom due to redundancy. Results were obtained for different behaviors: stabilization and target pursuit and approaching the target and moving to as far as possible from the target. [Motivation], [Overview], [People], [Publications], [Video]
Sericothrips variablilis Beach Appearance and Life History There are many species of thrips, some are serious pests of fruit, vegetables, flowers, and field crops. Thrips' mouthparts make them unique in that they rasp and puncture plant cells then suck up the exuding sap. Thrips are minute, slender-bodied insects ranging from 1/32 to 1/5 inch (0.8 to 5 mm) in length. Their wings, when present, are fringed with close-set long hairs. Although rarely noticed, thrips are probably the most numerous insects in soybean. The adult female inserts oblong eggs singly into the leaves of the plant upon which she feeds. Young thrips go through 4 wingless stages between hatching and adulthood. An entire life cycle requires only 2 to 4 weeks. Thrips are present throughout the summer. Many generations occur each year. Thrips make tiny, linear, pale-colored scars on soybean leaves where they penetrate individual leaf cells and feed on the contents. They usually feed on the undersides of leaves, much of which occurs along the veins. When leaves are heavily infested, the feeding scars may be so numerous that a mottling look appears along and between the leaf veins and leaves may become crinkled in appearance. Soybean is particularly susceptible to thrips damage early in the growing season from growth stages VE to V6. Dry, hot weather increases the threat of damage. If one finds or suspect thrips' damage during early field visits, sample in 5 areas of the field to ascertain the extent of the population and damage. In each area, randomly select the first plant to be sampled and remove the fifth trifoliolate down from the uppermost node from 10 consecutive plants. On younger plants, which have not reached at least the V5 stage, remove the lowest trifoliolate for inspection. As you pick the last trifoliolate in each sample area, use a hand lens to carefully examine the underside of the leaves and count the number of thrips present. Repeat this sampling pattern for each plant to be examined. Determine the average number of thrips per trifoliolate. Also estimate the percentage of foliar discoloration exhibited by each plant. Consider that drought-stressed plants may be exhibiting symptoms from other factors, eg., chemical injury, etc. Soybean Insect Control Recommendations: E-series 77-W (PDF) Thrips rarely cause economic damage. However, yields may be significantly reduced if soybean is under moisture stress early in the growing season and the thrips population is high. If over 75% of the sampled trifoliolates are damaged and there is an average of 8 thrips per leaf, treatment may be advisable. If control is necessary, contact your state Cooperative Extension Service or click here for control materials and rates.
A classic problem in concurrent programming is known as the “same fringe” problem . What is the same fringe problem? As described by Richard Gabriel : The samefringe problem is this: two binary trees have the same fringe if they have exactly the same leaves reading from left to right. There are many different approaches to solving this problem in a variety of languages. Our approach is to incrementally generate a stream of leaves from a tree (the fringe). We will use a comparison process to read from a pair of streams (one for each tree) and report if they are the same or different. Comparison stops as soon as we detect a difference, avoiding the need to generate the rest of the fringe. When we generate the fringe of a tree, we follow a stream-generator protocol. Before we get into the fringe itself, let’s examine a protocol for streams in general. A stream-generator receives requests with only a customer. It sends a pair to this customer consisting of a value and an actor to ask for the next pair. You can think of the actor as representing a position in the stream. A simple stateful stream-generator is one that generates an infinite sequence of values. LET sequence_gen_beh(value, fn) = \cust.[ BECOME sequence_gen_beh(fn(value), fn) SEND (value, SELF) TO cust ] The sequence begins with an initial value. When a request is received designating a customer cust, the mutable state of the stream is updated by applying a function fn to the value. The customer is sent a pair consisting of the original value and a reference to itself. Since its state has been updated with the new value, the actor to ask for the next value is the same actor. We can also generate the same sequence of values using immutable actors. LET sequence_gen_beh(value, fn) = \cust.[ CREATE next WITH sequence_gen_beh(fn(value), fn) SEND (value, next) TO cust ] In this implementation, rather than altering the state of the current actor, we create a new actor to represent the next value in the sequence. This allows us to retain references to actors representing any particular position in the stream and ask them to replay the stream from that position. The immutable implementation can be made more efficient by avoiding recalculation of successive values when the sequence is replayed. LET sequence_gen_beh(value, fn) = \cust.[ CREATE next WITH sequence_gen_beh(fn(value), fn) BECOME \cust.[ SEND (value, next) TO cust ] SEND cust TO SELF ] In this implementation, we only calculate the next value once. We change the actor’s subsequent behavior to always return the same value and next. We re-issue the request (the customer cust) to the updated actor. This is a form of memoization. Once initialized, each actor is immutable. Notice that all of these actor behaviors support the same protocol. From the perspective of a customer reading the stream only once, their observable behavior is identical. The mutable and immutable versions differ in their handling of repeated requested to the same actor. Specifically, the mutable version is not re-usable since it becomes the representation of the next position on each request. The fringe generator produces a stream of values, pairing each value with an actor representing the generator of the next value. Each fringe generator actor maintains a location in the tree, and the actor that will generate the next result. By convention, when next is NIL, we’ve reached the end of the stream. The generator has mutable state. It is intended to be used only once. LET fringe_gen_beh(tree, next) = \cust.[ IF $tree = (left, right) [ SEND cust TO NEW fringe_gen_beh(left, SELF) BECOME fringe_gen_beh(right, next) ] ELSE [ SEND (tree, next) TO cust ] ] When a customer cust requests a value, we check if tree is a branch or a leaf. If we have a leaf, we send the customer the leaf value tree and the next actor. If we have a branch, we create an actor to represent the left part of the tree, designating the current actor as next. We send the customer cust to the new actor in order to process the left sub-tree first. The current actor becomes the representation of the right part of the tree, using the original value of next. In this way, once the left sub-tree has been processed, the right sub-tree is processed as next. Once the right sub-tree has been processed, we continue with the original next. Figure 4 illustrates the fringe 1, 2, 3, 4 generated from the tree (1, ((2, 3), 4)). Note how the fringe is generated incrementally. Each request only does enough work to locate the next element of the fringe. This property is critical to the efficient comparison of trees with large fringe, especially if they differ in the early part of the fringe. Checking two trees for the same fringe is accomplished by comparing corresponding values from two fringe-generator streams. We create an actor behavior for incrementally comparing two streams regardless of how they are generated. LET cmp_stream_beh(cust) = \(value, next).[ BECOME \(value', next').[ IF $value = $value' [ BECOME cmp_stream_beh(cust) IF $next = $next' [ SEND TRUE TO cust ] ELIF $next = NIL [ SEND FALSE TO cust ] ELIF $next' = NIL [ SEND FALSE TO cust ] ELSE [ SEND SELF TO next SEND SELF TO next' ] ] ELSE [ SEND FALSE TO cust ] ] ] The stream comparison actor is designed to be used as the customer for two stream-generators. It maintains its own customer cust to report a FALSE comparison result. When it receives a value and next from one of the streams, it transitions to a state waiting for the other stream. It doesn’t matter which stream generates a value first. When a value’ and next’ is received from the other stream, we now can compare corresponding values. If the values don’t match, we send FALSE to the original customer cust. We only read enough of each stream to locate their first difference, or keep reading (as long as they match) until they both end. If the values match, we prepare to receive (and compare) another set of corresponding values. However, before we can ask each generator to generate their next values, we have to check for termination conditions. If next and next’ match (usually because both are NIL), we send TRUE to the original customer cust, since we’ve successfully matched everything up through the end of both streams. If either next or next’ are NIL, we send FALSE to the original customer cust, since one stream has ended before the other. Otherwise, we send the comparison actor (our SELF) to each stream, requesting the next value from each. Using these building blocks, we can create a service to compare pairs of trees. CREATE same_fringe_svc WITH \(cust, a, b).[ CREATE match WITH cmp_stream_beh(cust) SEND match TO NEW fringe_gen_beh(a, NIL) SEND match TO NEW fringe_gen_beh(b, NIL) ] The service creates a new stream comparison process match that reports its results to the customer cust. A fringe generator is created for each tree. The comparator match is sent (as a customer) to both streams, initiating the process of reading and comparing corresponding values from each stream. The following test case generates a LET a = (1, ((2, 3), 4)) LET b = ((1, (2, 3)), 4) SEND (println, a, b) TO same_fringe_svc The following test case generates a LET a = (1, ((2, 3), 4)) LET z = (1, 0, 3, 4) SEND (println, a, z) TO same_fringe_svc An important property of the stream comparison process is that it avoids reading beyond the point of difference between the streams. This is especially important if one of the streams is infinite. Consider the result of executing the following: LET a = (1, ((2, 3), 4)) CREATE match WITH cmp_stream_beh(println) SEND match TO NEW fringe_gen_beh(a, NIL) SEND match TO NEW sequence_gen_beh(1, inc) The sequence generator will produce an infinite sequence starting with 1, 2, 3, 4... (assuming that inc is an integer increment function). The fringe generator will produce the same initial values, but ends after 4. The stream comparison process will report FALSE after the fourth value and stop reading the streams. The “same fringe” problem is considered one of the simplest problems that requires concurrency to implement efficiently. It seems to require a non-deterministic merge between two incrementally-generated streams of information. Asynchronous actor messaging provides the means for handling the non-deterministic merge (comparison). In addition, this problem provides an excellent illustration of the use of incremental stream generators. We will have much more to say about stream-based processing in future articles. - C. Hewitt, et. al. Behavioral Semantics of Non-recursive Control Structures, Proc. Colloque sur la Programmation, B. Robinet ed., in Lecture Notes in Computer Science, No. 19, Springer Verlag, 1974. - R. Gabriel. The Design of Parallel Programming Languages. http://www.dreamsongs.com/10ideas.html, 1991.
by Steve Voynick In recent years, rock shops and dealers at gem and mineral shows have been displaying large volumes of inexpensive, massive calcite from Mexico. In both rough and fabricated forms, this calcite has a soft translucency and comes in pleasing shades of red, orange, yellow and white. Most distinctive, however, especially in rough pieces, is its smooth, lustrous, glassy surface, which still retains many of its original, irregular projections and concavities. Although this undulating surface may seem to be the product of mechanical polishing, it is actually created by a much faster, cheaper, and less labor-intensive method—brief immersion in acid. Calcite, or calcium carbonate (CaCO3), crystallizes in the trigonal system. It occurs in many crystal habits, of which the most familiar is well-developed rhombohedrons. With a specific gravity of 2.7-3.0, calcite is only slightly denser than quartz. As a simple carbonate, the calcite molecule consists of a divalent calcium cation bound to a negatively charged (anionic) carbonate radical. The weak ionic bonding between the calcium ions and the carbonate radical explains many of calcite’s physical properties, including its relative softness of Mohs 3.0 and its tendency to cleave easily into rhombohedrons. Weak ionic bonding also explains another of calcite’s diagnostic properties: its vigorous effervescence in acids. The term “effervescence” refers to a foaming or “boiling” effect caused by the release of millions of tiny gas bubbles. Effervescence was a traditional demonstration in high-school chemistry classes; instructors would mix an acid and a carbonate compound, usually sodium bicarbonate (baking soda), to produce the violent foaming that is the principle behind soda-acid fire extinguishers. That same reaction occurs when acid contacts calcite. Using hydrochloric acid (HCl) as an example, calcite effervesces vigorously when the acid’s highly reactive chlorine ions (Cl1-) break its weak ionic bonds and replace its carbonate radicals. This reaction is stated by the formula CaCO3 + 2HCl = CaCl2 (calcium chloride) + H2O (water) + CO2 (carbon dioxide). The rapid release of carbon dioxide gas creates the bubbles of effervescence. Mineral-effervescence tests are usually performed with cold, dilute hydrochloric acid. Effervescence is apparent when just a single drop of this acid contacts a calcite surface. While all carbonate minerals will eventually dissolve in dilute hydrochloric acid, only a few effervesce vigorously. The action of cold, dilute hydrochloric acid on dolomite (calcium magnesium carbonate) generates only a subtle effervescence. This is because closer atomic packing within dolomite’s orthorhombic crystal lattice strengthens the ionic bonds between the calcium and magnesium cations and the carbonate anions, making dolomite much less susceptible than calcite to the chemical action of acids. Interestingly, acid-effervescence does not occur at all in aragonite, the orthorhombic polymorph of calcium carbonate. Although aragonite and calcite have identical chemistries, aragonite’s orthorhombic crystal structure has a much stronger ionic bonding that resists the action of acids. In the massive calcite now mined in Mexico, the red and orange shades are caused by tiny, included particles of hematite (iron oxide) in various sizes. The smallest particles are believed to produce red, while larger particles create orange and yellow. Much of this Mexican calcite is fashioned into cups, ashtrays, paperweights, figurines, and other decorative objects. Some, in pieces as large as 1 or 2 feet high, is kept in its rough shape to serve as home or office display pieces. After it is roughly fabricated or sized, this material is briefly immersed in acid to dissolve a thin layer of the calcite, leaving a smooth, lustrous, glassy surface. By greatly reducing the scattering of incident light, this surface improves translucency and intensifies the internal colors. Acid immersion also eliminates or makes smooth any remaining saw or wheel marks on fabricated pieces. Quick and inexpensive, acid immersion improves both the appearance and marketability of all that colorful Mexican calcite—thanks to that mineral’s diagnostic tendency to readily effervesce in acid.
The Paris Agreement adopted on December 12th, 2015, has secured its place in all future negotiations on climate change. Soon after the adoption of the agreement, it became clear that the document marked a turning point in the decades-long effort to avoid immense consequences of climate change caused by the burning of fossil fuels. The key element of the agreement is the requirement to hold the rise of global mean temperature well below 2 °C above pre-industrial levels. By fulfilling this requirement, humanity would have an opportunity to keep the consequences of climate change within the limits of what it is deemed controllable. What can also be considered as progress in the negotiations was the opening of the possibility to set the limit of temperature growth even lower. The agreement thus provides hope for a continuation of efforts to limit the rise to 1.5 °C. Furthermore, the 1.5 °C limit is more widely accepted among scientists as a safe zone. During the negotiation of the deal, this was particularly insisted upon by small island states because rising sea levels may leave them underwater, in case that the limit is set at 2 °C. The final document, therefore, calls upon the Intergovernmental Panel on Climate Change to soon prepare a special report focusing on the consequences of global temperature rise by 1.5 °C. The report should also feature methods to achieve this ambitious goal in the context of reducing greenhouse gases, which could serve as an important base for marshaling support for further serious consideration of the report in future negotiations. Before the commencement of the two-week negotiations in Paris, we have seen intensive communication unfold between parties of the Convention, finally resulting in the submission of the 186 Intended Nationally Determined Contributions (INDCs), which represent respective national plans to reduce greenhouse gas emission. Some preliminary estimates of the cumulative contribution of all parties that have submitted their plans—who altogether make for 95 percent of total global emission—indicates that such contribution remains insufficient to reach the 2 °C goal, and will instead lead to nearly 3 °C rise. This fact was clearly stated in the agreement, and is precisely why many are expecting more ambitious planning in the future to achieve the set goals. According to the agreement, the process of producing the INDCs will be iterative, while at the same time members have committed to submit new updated plans every five years, thus making the set goals more realistic. By clearly stating the fact that the existing plans will not lead to definitive solutions, it becomes clear that one agreement cannot solve everything—certainly not when facing such a complex problem. Irrespective of which of the goals will be adopted in the end during future negotiations, what is necessary for them to succeed is for global net emissions of greenhouse gases to level at zero in the second half of the 21st century. In practice, this means completely abandoning fossil fuels as a primary source of energy, and a rapid transition to renewable energy sources. The difference between the 2 °C and 1.5 °C goal is in the speed of this transition. The only chance for small gas emission from fossil fuels to remain present in the future lies with the existence of negative emissions, whether as part of the natural process or in technological solutions. At this moment though, the capacities of existing technological solutions indicate minimal chances for the implementation of such options. The great expectations for a decisive shift in energy production methodology were the reason for why some stated that the meeting in Paris should mark the end of the era of fossil fuels. Another very important element of this agreement is the creation of a fund that will help developing countries, the transformation of their energy systems, and their effective adaption to changing climatic conditions, enabling them to reduce negative effects of climate change to as little as possible. The financing for this fund should be provided by governments of developed countries starting in 2020, with minimum annual contributions amounting to $100 billion. It is important that the year this agreement is adopted coincides with the fact that this year is also the warmest on record. The global mean temperature anomaly in 2015 will have such an effect on global climate that the total temperature rise of 0.85 °C that has occurred since the pre-industrial period will next year come close to 1 ° C. During this year, the concentration of carbon dioxide in the atmosphere exceeded 400ppm. The concentration of carbon dioxide for the last eight hundred thousand years has been in the range of 170 to 300 ppm, and it is estimated that the world will require hundreds, if not thousands of years, to return to the likes of the pre-industrial period. Why, then, should one be optimistic? Although the amount of the total annual electricity generated by solar and wind sources still accounts for only a small percentage of total production, estimates for its increase by the International Energy Agency in the mid-1990s were almost 10 times less than current figures. In 2014, the trend of increase in global emissions was close to zero, while estimates for 2015 indicate that we can expect a further drop. Should the Paris Summit be understood as the event that sent a strong signal of support to such modest but significant trends, then its role could be more important than the adoption of the agreement itself. Vladimir Djurdjevic is professor at the Institute for Meteorology at Belgrade University's Faculty of Physics.
English Body Matching Worksheet \| Printable PDF English body matching worksheet for students to practice the words: arm, hand, fingers, leg, foot, and toes. ESL, ELL, and early learners will have fun as they reinforce vocabulary in a natural way. Have your student use a crayon, coloured pencil, or marker to draw a line from the picture of each body part to their names. After matching, spell out each word and say the word for practice! What language skills are being developed? This matching activity is a great resource to introduce early learners to animals and new vocabulary. Matching activities promote: - Vocabulary reinforcement - Fine motor skills - Recall or memory Teaching nouns to your student Nouns can be described as people, places or things. In these colouring pages, we are working with nouns. You can practice this vocabulary at home by doing lots of fun activities! For other fun activities and more check out our learning resources page!
Scientists might have finally worked out how Antarctica was rapidly buried in a thick sheet of ice 34 million years ago. They believe that two factors contributed to glaciation of the southernmost continent. Their research is published in Nature Geoscience. The Drake Passage (the region between South America and Antarctica) deepened, changing how water circulated in the oceans globally. The change shifted the direction of the warmer currents coming from the tropics, which were directed to northern latitudes. The other contribution comes from the reduction of carbon dioxide in the atmosphere. CO2 levels have been declining since the beginning of the Cenozoic Era 66 million years ago, but the sudden change in the ocean current led to more rain, which brought CO2 below the critical value. This mean't Antarctica became frozen. "It's an interesting lesson for us when it comes to climate change because what we get is a thumbnail shift between two stable climatic states in Antarctica – from no glaciers to glaciers,” said co-author Dr. Galen Halverson, from McGill University, in a statement. “And what we see is both how complex climate changes can be and how profound an effect changing patterns of ocean circulation can have on global climate states, if looked at on a geological time scale." The two factors were seen before as competitive explanations for the frosting of the South Pole, but the researchers realized they were two sides of the same coin. According to the scientists, the deepening of the Drake Passage started the powerful Antarctic Circumpolar Current. The looped current kept the cooler water near the continent and acted as a barrier from the warmer, less salty waters from the North Atlantic and Central Pacific. Those currents were redirected towards the other continents, increasing rainfall. Rainfall increases the amount of weathering of rocks, a process that slowly traps the atmospheric CO2 inside limestone. The researchers think that nobody considered combining the two ideas before because they happen on different timescales. Currents change over thousands of years, while rock weathering happens over hundreds of thousands of years. But once combined, they were probably enough to bury Antarctica in ice and snow.
Overview, Causes, & Risk Factors Cerebrospinal fluid, also known as CSF, leak is an abnormal drainageof cerebrospinal fluid from the subarachnoid space in the brain.The fluid may leak out into the body, but more often it is seen leakingthrough the ears, nose, or an open wound. What is going on in the body? CSF is formed within the inner spaces of the brain calledventricles. The fluid travels through the ventricles and exits thebrain beneath the cerebellum, which is at the base of the head. It then travelsdown the spine, around the spinal cord and nerves, and back up to thehead. The final step is passing over the top of the brain where it is absorbed.The fluid is held between the arachnoid and dura membranes. Thesemembranes enclose the brain and spinal cord. Leakageoccurs when the arachnoid membrane is ruptured. What are the causes and risks of the condition? A CSF leak is caused by a rupture of the arachnoid membrane.This usually results from trauma, although it can occur spontaneously.Tissue destruction caused by tumors could lead to a CSF leak. Symptoms & Signs What are the signs and symptoms of the condition? CSF is a clear, watery liquid that leaks out of the nose, ear,or a wound. Headacheis common with a CSF leak. It may be relieved when the person sits upright from a lyingposition. However, changing to this position may cause the flow of fluid toincrease. Coughing or sneezing can also cause an increased flow of CSF. Diagnosis & Tests How is the condition diagnosed? Diagnosis is made through observation and by testing anysuspicious watery fluidfor glucose, which is present in cerebrospinal fluid. X-ray studies maybe needed to find the exact place where the membrane has ruptured.Other studies may include CT scans. Prevention & Expectations What can be done to prevent the condition? There is no way to prevent a CSF leak except by avoidingtrauma. Sports safety guidelines for children,adolescents,and adultscan help avoid head injury during sports. What are the long-term effects of the condition? Chronic leakage may occur at times. The leak most commonlycomes from the nose. A long-term result may result in the loss of the senseof smell. What are the risks to others? There are no risks to others. Treatment & Monitoring What are the treatments for the condition? Leakage through the nose or ears following traumausually gets better with rest. Antibiotics are given if an infection ispresent. If the leakage persists, the doctor may place catheters inthe lumbar spine to reroute the CSF. Surgical closure ofthe ruptured membrane is rarely needed. If leakage is caused by erosiondue to tumor or infection, the underlying cause must be treated. What are the side effects of the treatments? Infection of the trauma site and failure of the rupture toclose spontaneously may sometimes occur. In cases of a skullfracture, swelling may damage a cranial nerve, leading to weaknessor paralysis on the side of the face. These injuries commonly result inhearing loss on the affected side. What happens after treatment for the condition? Treatment is usually successful, although complicationssuch as infection can occur. How is the condition monitored? A person should be monitored for infection and recurrenceof CSF leakage. A change of therapy may be needed if infection orrecurrence takes place. Any new or worsening symptoms should bereported to the doctor. Article type: xmedgeneral
The Notre Dame de Paris is located in Paris, France. (Notre Dame meaning ‘Our Lady’) Construction of the cathedral began during the Early Gothic period between 1163 and 1250 C.E. The bishop who oversaw the construction was Maurice de Sully. The original master mason (the term architect was not used for many years to come) is unknown, but is obviously someone quite capable of manifesting Sully’s intentions. The church was a tangible representation of the newly acquired power of Paris. The French were to spare no costs in their building of Notre Dame so as to exemplify their accomplishments. The materials used to build the 110 ft (approximately 30 m) high cathedral were for the most part taken from local quarries. Even though the location of the quarries was nearby transporting the large stones required was costly. To economize, much of the initial shaping of the stones was done at the quarries themselves and the cutting was finalized at the site. Construction of the cathedral was done in three stages. The first parts of the structure to be completed were the choir, apse, and chancel. After the completion of these spaces the building could continue to be used throughout the construction. The breadth and height of the vaults in Notre Dame surpassed any buildings that had been built. The innovative structural techniques allowed for more light and space. One of the important innovations was the combination of triangular ribs and transverse arches. These elements were primarily hidden unlike the exposed and intrusive elements that existed previously in the Romanesque period. The flying buttresses used in Notre Dame are considered some of the earliest in existence; however there have recently been discovered similar buttresses that are from an earlier time period. Maurice de Sully passed away in 1196 with the completion of the nave. Maurice’s successor, Bishop Eudes de Sully (no blood relation), become the overseer of the construction for the next fifty years. Eudes de Sully was a wealthy noble and decided to enlarge the plans for the cathedral contributing his own money to the funding. The changes to the plans are most evident in the western façade. It took twenty-five years to complete the façade up to the rose window and yet and twenty-five years to complete the two towers. Other than the west façade the structure remained true to the original plans. The façade of the cathedral is a careful balance of vertical and horizontal elements. This gives the exterior stability that has lead to it being remembered as quintessentially Early Gothic. The grid created by the horizontal and vertical balance accentuates the stained glass rosettes. In order to allow for more light to enter the space the windows were enlarged and lowered. The plan contains a five-aisled structure containing a Romanesque bay system combined with Early Gothic nave vaulting. Four hundred years after the completion of the cathedral many changes were made. At this time Baroque art and architecture was the standard and the Gothic style was seen as barbaric at best. Due to this generally negative perception of the Gothic style the stained glass windows were removed, tombs were destroyed, and a high alter was constructed. Soon before the French Revolution sculptures and gargoyles were removed from the exterior of the church because people saw them as tasteless. During the height of the Revolution the sculptures adorning the cathedral were smashed and the heads of the statues were given away as trophies. A series of sculptures known as the gallery of kings on the west façade was completely destroyed. The broken pieces of the building were not removed from the site for three years. After the revolution the primary use of the structure was for non-religious gatherings. In the nineteenth century the Romanticists began an attempt to restore the cathedral. In 1831 Victor Hugo wrote The Hunchback of Notre Dame. Little did he know that his book would inspire many to take an active role in the recreation of the original splendor of the building. One of those who was inspired by Hugo’s writing was an aspiring architect named Emmanuel Viollet-le-Duc. Viollet-le-Duc had fairly extensive knowledge of the Gothic style and was therefore able to oversee an accurate restoration. The gallery of kings and gargoyles were replaced and the white washed interior was removed during the twenty-three years the restoration occupied. Sources and Images: Gardener’s Art Through The Ages Tenth Edition
Last Updated on August 31, 2021 by Thinkster For many children, the bigger challenges they face with 5th grade math word problems can trip them. Even when word problems were easy in earlier grades, the multiple steps and bigger numbers in fifth grade can create problems for many students. Here are some cool ways you can help your child learn 5th grade math word problems. For Word Problem Bingo, you will need a total of 24 fifth grade math word problems. Figure out the answers ahead of time, and give the child the answers along with a five-by-five Bingo grid. Then, instruct your child to fill in the grid using the answers however he sees fit. You do the same. Remember that the center space is a “free” space. Mark it with a star or smiley face. To play, select a random word problem and solve it independently, placing a marker on the answer. Your child will be able to self-check because he will know that he did not get the right answer if it is not on his grid. The first person to fill five in a row is the winner. Surveys provide excellent opportunities to explore percents, ratios, tables, graphs and averages. Kids love to take surveys and gather the data, then you can use the data to determine many facts about the question you ask. You can survey relatives, classmates, neighbors or even random people you meet around town. Some good ideas for survey questions include: The key to making this a successful project is to choose questions that will get a range of answers, and then to get a sampling of answers from many different people. Once you have gathered the data, ask the child to average it, find the percent of people who answered with a particular number, find ratios of two values to each other or two percents to each other and graph the information. If your child is having a hard time remembering the keywords used in 5th grade math word problems, this activity can help. Draw some simple bugs on a large piece of butcher paper. The bugs should be about the size of a fly swatter. Then, on each bug write an operation sign or word, such as + or “addition.” Say a key word from a word problem, like “Each,” which means multiplication. When you say the word, your child should hit the appropriate bug with a fly swatter. Remember, 5th grade word problems are entirely possible with a little bit of learning. Yes, in fifth grade the problems get more challenging, but your child is up for the challenge. Give him additional help and support by enrolling him with Thinkster Math. This proven iPad-based learning system will ensure he knows everything he needs to know about solving math word problems, so you, and he, can have success. Our elite math tutors are ready to help make your child a math champion! Sign up for our zero $ free trial to get started today.Start Zero $ Free Trial
New research from the Naval Medical Research Unit Dayton sheds light on the black hole illusion, a dangerous phenomenon — also known as the black hole effect or featureless terrain illusion — that affects pilots attempting to land at night. The study, published in The International Journal of Aerospace Psychology, provides evidence that the illusion occurs because the human perceptual system attempts to recreate the horizon when a pilot cannot actually see it. “The black hole illusion is one of the most commonly reported visual spatial disorientation illusions, and can lead to tragic consequences if the illusion is severe enough,” explained study author F. Eric Robinson, a research psychologist at the Naval Aerospace Medical Research Laboratory at Wright-Patterson Air Force Base. “There is a relatively good understanding of the factors that make black hole illusions more likely, but there is not a definitive mechanistic explanation for the illusion itself. We, at NAMRU-Dayton, saw an opportunity to approach the black hole illusion in a new way in order to protect and enhance the readiness, performance, and survivability of naval and joint warfighters.” Robinson and his colleagues hypothesized that a line bias illusion could explain why the black hole illusion occurs at night. They noted that “human vision is predisposed to creating a cohesive perceptual interpretation” and has been shown to “fill in” missing components of visual scenes. In the case of a pilot flying at night, this missing component is the horizon. The researchers believe that pilots unconsciously estimate the position of the horizon based on the projected convergence point of runway edge lights. But since runway edge lines stop far short of their intersection at the horizon, it is unclear how accurate these estimates are. In three experiments, which included 36 participants, the researchers examined how well people could estimate the intersection of angled line segments. The line segments consisted of white dots against a black background, similar to what a pilot would see on the final approach to the runway at night. Robinson and his colleagues found that participants tended to misjudge the convergence point, indicating they would also misjudge the location of an implicit horizon based on runway lights. The misjudgment would cause an implicit horizon to be too low in the visual field, particularly early in the approach, which in turn could cause a pilot to adopt a low flight path. “If our hypothesis is supported by future research, it would indicate that we have a strong tendency to rely on preferred spatial strategies even when some of the necessary information is missing. If our perceptual systems try to fill in the gaps, errors can occur. Basic perceptual mechanisms can have potentially profound effects on behavior,” Robinson told PsyPost. Though the line segments used in the study resembled runway edge lights, they were not entirely representative of what a pilot would encounter at night. The researchers hope to use more realistic stimuli in future research examining the illusion. “We found support for individual elements of our hypothesized explanation for black hole illusion. We are looking to do follow on research to further address the potential causal relationship between the line bias illusion and black hole illusion,” Robinson explained. “We still need to replicate our findings using stimuli that better represent the aviation environment, specifically the runway sizes and line angles a pilot would see. We also need to test pilots in a flight simulator to see if the perceptual errors we observed actually affect performance and induce the black hole illusion.” “NAMRU-Dayton conducts research at the highest levels of experimental and technical quality in order to best support the operational needs and requirements of our service members,” Robinson added. “NAMRU-Dayton’s unique set of human-rated acceleration devices allows us to maintain a technology base critical to Naval Aviation and federal and non-federal aerospace customers. The study, “Preliminary Support for the Line Bias Illusion as a Contributor to Black Hole Effects“, was authored by F. Eric Robinson, Henry Williams, and Adam T. Biggs.
NOW THROUGH 12/31/21: Buy 5 B1-1 or B1-1F, get 1 B1-1F FREE!!! Objective: To study the effects of DNAse I and denaturation on the structure of DNA. The DNA molecule from a single human chromosome is about 4 cm long and the length of DNA in an individual is about 200 times the distance from the earth to the sun. Isolated DNA in a test tube is also a long, stiff molecule. When alcohol is added to a DNA solution, the DNA fibers precipitate and can be spooled onto a glass rod. This feature of DNA is illustrated in the exercise, which provides enough purified DNA for 16 students working in pairs to perform the experiment. The spooling phenomenon is also used by the student to study the double-stranded nature of DNA and to investigate the effect of breaking DNA into small pieces with the enzyme DNAse. 80 ml Calf Thymus DNA 1 ml DNAse I 8 glass vials 8 glass rods for DNA spooling 10 small transfer pipet – These pipets should be used for the DNAse I solution. 10 large transfer pipets Materials Not Provided Ice chips in a beaker Boiling water bath (A 250m1 beaker with water over a burner can be used.) 16 glass test tubes and a few metal tube holders 1% NaCI – (OPTIONAL – see below and Instructor Manual) Experiment (B1-1). Properties of DNA DNA is an extremely long molecule that is very thin, yet quite rigid. The isolation of intact DNA molecules from a cell is difficult because of the relative ease with which these long rod-like molecules can be broken. Even the injection of a solution of DNA through the needle of a hypodermic syringe can cause extensive breakdown of DNA molecules. DNA can also be broken down by enzymes called deoxyribonucleases. Deoxyribonuclease I (DNAse I), an enzyme isolated from the mammalian pancreas, will be used in today’s experiment. This enzyme breaks the phosphodiester bonds that connect the nucleotide units in DNA, degrading long DNA molecules to a mixture of small nucleotide chains, as illustrated in Figure 1-1. A DNA molecule is composed of two polynucleotide chains that are coiled around each other to form a rigid double-helix (see page 4). The double-helical structure of DNA is very stable at room temperatures because the hydrogen and hydrophobic bonds between the stacked bases hold the two polynucleotide chains together. However, if a solution of DNA is heated to a critical temperature, these bonds are broken and the two polynucleotide strands separate by a process called denaturation. DNA denaturation is accompanied by a decrease in the viscosity (thickness) of the solution because single-stranded DNA molecules form flexible coiled structures that no longer retain the rigid native structure of the DNA double-helix (Figure 1-2). If the DNA is cooled rapidly, the molecules will remain as single stranded polynucleotides. However, if the solution is cooled very slowly, restora¬tion of the DNA helix will occur. The reassembly of the two separated polynucleo¬tide strands is called renaturation. Macromolecules such as DNA, RNA, and protein are not soluble in alcohol solutions, and precipitate (come out of solution) upon addition of alcohol. In general, globular proteins and RNA form fine, non-fibrous precipitates in alcohol. In contrast, the rod-like DNA molecules precipitate in alcohol as long fibers that can be spooled onto a glass rod. The ability of DNA to form fibers in alcohol depends on the physical properties of the DNA molecules. For example, DNA that has been broken into small pieces by DNAse I digestion will not form fibers, nor will single-stranded DNA that has been prepared by heat denaturation of the DNA double-helix. These properties of DNA will be illustrated in today’s experiments. Study Questions and Analysis 1. Describe the basic properties of DNA that are responsible for fiber formation when alcohol is added to a solution that contains native (double-stranded) DNA. 2. Describe the type of precipitate that is formed when alcohol is added to denatured (single stranded) DNA. Offer an explanation as to why this precipi¬tate is different from that which is observed with native DNA. 3. Describe the action of DNAse Ion DNA and relate this effect to the results of your experiment in Section HI.
School Zone Vocabulary Puzzles Grade 1 Workbook Help your child explore language and improve word skills. This Vocabulary Puzzles 1 workbook helps first graders practice dozens of vocab words. Support spelling, writing and reading goals with imaginative activities and delightful picture clues that make learning new words fun. They include words that name animals, people, and places; words that are opposites; action words; words that describe how things taste and feel. Word searches, codes, crosswords, and other kid-pleasing puzzles will entertain children while they learn. The slim size of our first grade workbooks is great for packing into totes, backpacks and luggage. - long vowels - short vowels - critical thinking - following directions
resources for reading intervention Available for grades K–3, the Select Collections offer books to use in small-groups, guided reading and for independent, partner and take-home reading. Have two students partner up and take turns being the “teacher” to explain a concept. Make sure this account has posts available on instagram.com. It can be so hard knowing what our students need and how to help them. This helps transition from broken, segmented sounding out into the smooth sounding out that helps students learn to say the whole word. Then use your right hand to pat down your shoulder as you say each sound. Try some of the touch-intervention activities included in my CVC Intervention Binder, Phonics Intervention Binder, or Fluency Intervention Binder. The resources and review tools provided below include interventions studied by independent clearinghouses that have evaluated the existing research on specific interventions to assist educators in making evidence-based decisions when selecting interventions to support instruction for students that have been identified as needing a tiered system of reading support. For example, circle the vowels, underline the prefixes, cross out the silent letters, or breaking apart chunks/syllables. It gets students moving and blood flowing so they have the energy to think, but it also stimulates parts of the brain in a way that it helps students focus better. Use arm slides as a reading intervention activity for blending sounds. You could use blue for consonants and red for vowels, pink for a phonics pattern and purple for the rest of the word, green for the base word and yellow for the ending, etc. For the word “pin”, I had each student hold up their finger, and gently brushed each finger with the tip of the pin. This situation often leads to intervention as a strategy for boosting the skills of slow or reluctant readers. For example, we were learning the “-in” word family. Once you’re feeling good about reading intervention, then go check out this post for 11 Effective Reading Intervention Strategies you can implement now. I use it at the beginning of the year when we are working on blending words together. Get the latest information on news, events & more. I like to have the part we are focusing on be in a color that stands out more. Basically, you give them something to touch or experience for each word. Music can be a fun and effective reading intervention. Rhythm provides great listening cues as well as repetition and tactile/kinesthetic input. With engaging leveled books, fast-paced systematically designed lessons, and a high level of built-in professional development, LLI empowers both teachers and students as together they work toward attaining reading and writing proficiency. The National Center on Intensive Interventions website provides information on the importance of instructional practices and interventions specific to the student’s need. When I taught the alphabet, I used pictures of words that went with each sound that the letter made EVERY day. It has student characteristics, tips, and activities specific to each area of reading. Explore what a Choice Library is, what's included, how it's implemented, and gain access to webinars, and more. Check out these Reading intervention binders that have touch activities to practice skills. They wipe off pretty easily with a tissue or a baby wipe. For these reading intervention activities, write one letter, word, or sight word on a piece of paper and lay them out in a line. Use play-dough as a fun, hands-on reading intervention activity. Row, Row, Row Your Boat- “A, a, a says /a/; a says /a/ /a/ /a/; a, a, a, a; letter a says /a/” or with any 3 letter word “a n d spells and; a n d spells and” etc. I wrote a whole blog post that you can read HERE about this. You can have actions already made up, but I have found that they are more memorable if the students help you come up with them. Below are some specific reading intervention activities that I have found helpful in reaching my lowest sweet readers. Reading intervention activities to use with your struggling students who are visual learners. Next, for the word “chin” I had them gently touch their neighbor’s chin. Let students roll a die to move their game pieces, and read/define whatever word they land on. It can make the difference in teaching your struggling readers how to read. Slinkies and Rubber bands are great manipulatives to use in your reading intervention activities. **I would just focus on switching the first, middle OR last letter for each lesson, not all three at once. Here are some fun ideas from amazon! Color coding reading intervention activities work great for specific phonics patterns. Rhymes are another way to help cue students’ memories for vocabulary words, spelling words, or key concepts. Use white boards with dry erase markers for extra engagement! phrase students can memorize and think whenever they come across a certain skill. Having buttons to press and interact with is another good way to reach kinesthetic learners. You can have posters hung up on the wall, or print out little cards to put on a binder ring to use as a personal visual cue booklet for students to keep at their desks. When the light bulb clicks and you see their faces light up with confidence. Have students write their spelling word, sight word, or letter and draw pictures to represent it. The Key to Stress Free Reading Intervention, Word Endings St. Patrick’s Day Activities. Make a CVC word together, and then discover other words in the same word family by swapping out the first letter. office was tasked in s. 1001.215(8) F.S. This is perfect for a brain-break or a warm-up. For a fun reading intervention activity, use toy cars to drive out the sounds in words. Any cookies that may not be particularly necessary for the website to function and is used specifically to collect user personal data via analytics, ads, other embedded contents are termed as non-necessary cookies. The Just Read, Florida!
Drive systems convert electrical into mechanical (kinetic) energy using electrical machines and play a key role in automation systems, which require many movements to be carried out using electric drives. Electronics are vital and used to control the drives as well as supply them with electrical energy. Classic electrical machines are synchronous, asynchronous and direct current motors. Decentralised drive systems In a decentralised drive system, only the power supply and, if required, components of a central open-loop control system of the multiple-motor configuration are installed in a control cabinet. All other functional units such as frequency inverters and closed-loop control systems are fitted near the motors or directly on them. This concept is of particular advantage for large machines or plants, or machines or plants that are spread out over an extensive area. See Fig. 1 Drive systems Centralised drive systems In centralised drive systems, the power supply, frequency inverters, motor controllers and various control units of the multiple-motor configuration are housed in a central control cabinet. The motors and other process-related control elements are supplied or controlled from this cabinet, and required sensor signals are returned there. See Fig. 1 Drive systems
Widespread research into the efficacy of solar geoengineering has been stalled for years due to controversy. Opponents believe such science comes with unpredictable risks, including extreme shifts in weather patterns not dissimilar to warming trends we are already witnessing. Environmentalists similarly fear that a dramatic shift in mitigation strategy will be treated as a green light to continue emitting greenhouse gases with little to no changes in current consumption and production patterns. SCoPEx will take a small step in its early research this June near the town of Kiruna, Sweden, where the Swedish Space Corporation has agreed to help launch a balloon carrying scientific equipment 12 miles (20 km) high. The launch will not release any stratospheric aerosols. Rather, it will serve as a test to maneuver the balloon and examine communications and operational systems. If successful, this could be a step towards a second experimental stage that would release a small amount of CaCO3 dust into the atmosphere. David Keith, a professor of applied physics and public policy at Harvard University, recognizes the “very many real concerns” of geoengineering. It is true that no one knows what will happen until the CaCO3 is released and then studied afterward. Keith and fellow SCoPEx scientists published a paper in 2017 suggesting that the dust may actually replenish the ozone layer by reacting with ozone-destroying molecules. “Further research on this and similar methods could lead to reductions in risks and improved efficacy of solar geoengineering methods,” write the authors of the paper. The exact amount of CaCO3 needed to cool the planet is unknown, and SCoPEx scientists similarly cannot confirm whether it is the best stratospheric aerosol for the job. Early research suggests that the substance has “near-ideal optical properties” that would allow it to absorb far less radiation that sulfate aerosols, causing significantly less stratospheric heating. This is the purpose of the experiment: once a safe, experimental amount of CaCO3 is released, the balloon will fly through it, sampling atmospheric reactions and recording resulting dynamics. Frank Keutsch, the project’s principal investigator, does not know what the results might bring. The perfect aerosol would not immediately tamper with stratospheric chemistry at all: “The only thing it would do is scatter maximum sunlight and hence cool down the planet.” Proponents of geoengineering have cited the global cooling effects of volcanic eruptions that result from the introduction of sulfuric ash into the atmosphere. The 1815 eruption of Mount Tambora in Indonesia resulted in the “year without a summer,” while the 1991 eruption of Mount Pinatubo in the Philippines lowered global average temperatures by 0.5° C. Deliberate introduction of similar particles could potentially counter decades of greenhouse gas emissions. A report by the Intergovernmental Panel on Climate Change suggested the SCoPEx procedure could lower global temperatures by a full 1.5° C for no more than $1-10 billion a year. Again, these temperature decreases bring with them serious risks. Freezing temperatures in 1815 led to failed crops in near-famine conditions. British scientists have cited stratospheric aerosols from volcanic eruptions in Alaska and Mexico as the potential cause of drought in Africa’s Sahel region. Major disruption of the global climate could bring unintended consequences, negatively impacting highly populated regions and engineering another refugee crisis. David Keith has proposed the creation of a “risk pool” to compensate smaller nations for collateral damage caused by such tests, but such a payout might be little comfort to those displaced by unlivable conditions. The United States, Brazil, and Saudi Arabia blocked a 2019 United Nations assessment of global geoengineering plans. International cooperation will be required to assess the risks, winners, and losers of any such experiment, and how best to proceed with all in mind. Considering the unknown risks attached to solar geoengineering, OECD members should continue in their efforts to develop economically attractive renewable energy technology, even as it supplements such efforts with limited and careful research and experimentation. With assistance from Hayley Arlin and James Grant
Storify is an online tool that allows the user to collect various types of texts to create a story. This story could be about a famous historical figure, a current event, an idea for a project, the plot of a story, or something else entirely. There are lots of possibilities! Ease of Use One great aspect of Storify is that it’s super easy to use. Once you’ve signed up and decided what to call your story, you simply use the search tools on the right side to find the text you want to use. Options include tweets, Facebook posts, blog posts, Youtube videos, Instragram images, other Storify stories, and more. Once you search for what you’re looking for, Storify pulls up matching information and you drag the post/video/tweet/whatever into your story. Rearranging is also as easy as drag-and-drop. You can click between pieces to add text in order to give information about the media you’re using or give some commentary. When you’re finished with your story, you have lots of options for sharing it, including embedding it in a website like I did below. Ideas for Use In English Language Arts, students could create a Storify story following the timeline of a character from the story. They could add posts, images, media, etc. that the character could have posted or would have been interested in. In Science, students could follow the lifecycle of an animal, including information about what the animal eats, interesting stories from the science world about the animal, what kind of environment it lives in, video of the animal in action, etc. In Math, students could tell the story of how a theory was developed or how to work a particular type of problem. Story pieces could be video of themselves working a problem, posts about how the formula used was developed, application of the theory or formula in real life, etc. In History, students could trace the life of a famous historical person, integrating tweets from historians, documentary footage, timelines of the person’s life, etc. In Art, Music, or Film, students could tell the story of a particular artistic movement, including images of paintings (for example) from the beginning, middle, and end to show how it evolved over time. They could also include video of someone painting in that style, or an analysis of the style. In Languages, students could create a story of their learning or the evolution of a language, including video of themselves speaking in their new language, text about the development of the language, images of the alphabet, etc. Below is an example of a short story I created (click here if you can’t see it):
2 Sustainable Development What is the relationship between resource use and sustainable development?Sustainable development provides for human needs while preserving the ecosystems that produce natural resources. 3 Sustainable Development Goods are things that can be bought and sold, that have value in terms of dollars and cents.Services are processes or actions that produce goods.Ecosystem goods and services are the goods and services produced by ecosystems that benefit the human economy. 4 Ecosystem Goods and Services Healthy ecosystems provide many goods and services naturally and largely free of charge, like breathable air and drinkable water.But, if the environment can’t provide these goods and services, society must spend money to produce them.In many places, for example, drinkable water is provided naturally by streams, rivers, and lakes, and filtered by wetlands. 5 Renewable and Nonrenewable Resources Ecosystem goods and services are classified as either renewable or nonrenewable.A renewable resource can be produced or replaced by a healthy ecosystem. Wind is a renewable resource.Some resources are nonrenewable resources because natural processes cannot replenish them within a reasonable amount of time. Fossil fuels like coal, oil, and natural gas are nonrenewable resources formed from buried organic materials over millions of years. 6 Sustainable Resource Use Using natural resources in a way that does not cause long- term environmental harm is called sustainable development.Sustainable development should cause no long-term harm to the soil, water, and climate on which it depends. It should consume as little energy and material as possible.Sustainable development must be flexible enough to survive environmental stresses like droughts, floods, and heat waves or cold snaps.Sustainable development must also take into account human economic systems as well as ecosystem goods and services. 7 6.2 Using Resources Wisely Lesson Overview6.2 Using Resources Wisely 8 Soil ResourcesThe mineral- and nutrient-rich portion of soil is called topsoil.Good topsoil absorbs and retains moisture yet allows water to drain. It is rich in organic matter and nutrients, but low in salts. Good topsoil is produced by long-term interactions between soil and the plants growing in it.Topsoil can be a renewable resource if it is managed properly, but it can be damaged or lost if it is mismanaged. 9 Soil ErosionThe dust bowl of the 1930s was caused, in part, by conversion of prairie land to cropland in ways that left soil vulnerable to erosion.Soil erosion is the removal of soil by water or wind.Soil erosion is often worse when land is plowed and left barren between plantings. When no roots are left to hold soil in place, it is easily washed away.When soil is badly eroded, organic matter and minerals that make it fertile are often carried away with the soil. 10 Soil ErosionIn parts of the world with dry climates, a combination of farming, overgrazing, seasonal drought, and climate change can turn farmland into desert. This process is called desertification.Deforestation, or the loss of forests, can have a negative effect on soil quality. More than half of the world’s old-growth forests (forests that had never been cut) have been lost to deforestation.Healthy forests hold soil in place, protect the quality of fresh water supplies, absorb carbon dioxide, and help moderate local climate. 11 Soil Use and Sustainability Leaving stems and roots of the previous year’s crop in the soil can help hold soil in place between plantings.Crop rotation—planting different crops at different seasons or in different years—can help prevent both erosion and nutrient loss.The practice of contour plowing involves planting fields of crops across, instead of down, the slope of the land. This can reduce water runoff and therefore erosion.Terracing—shaping the land to create level “steps”—also helps hold water and soil.Selectively harvesting mature trees can promote the growth of younger trees and preserve the forest ecosystem, including its soil. 12 Freshwater ResourcesHumans depend on fresh water and freshwater ecosystems for goods and services, including drinking water, industry, transportation, energy, and waste disposal. Some farmland relies heavily on irrigation, in which fresh water is brought in from other sources.Some sources of fresh water are not renewable.Only 3 percent of Earth’s water is fresh water—and most of that is locked in ice at the poles. 13 Water PollutionFreshwater sources can be affected by different kinds of pollution. A pollutant is a harmful material that can enter the biosphere.Pollutants that enter water supplies from a single source—a factory or an oil spill, for example—are called point source pollution.Pollutants that enter water supplies from many smaller sources—the grease and oil washed off streets by rain or the chemicals released into the air by factories and automobiles, for example—are called nonpoint source pollution. 14 Industrial and Agricultural Chemicals One industrial pollutant is a class of organic chemicals called PCBs that were widely used in industry until the 1970s.Because PCBs often enter mud and sand beneath bodies of water, they can be difficult, if not impossible, to eliminate.Other harmful industrial pollutants are heavy metals like cadmium, lead, mercury, and zinc.Biological magnification occurs if a pollutant, such as DDT, mercury, or a PCB, is picked up by an organism and is not broken down or eliminated from its body. Instead, the pollutant collects in body tissues. Fig p.161 15 Residential SewageSewage contains lots of nitrogen and phosphorus. Large amounts of sewage can stimulate blooms of bacteria and algae that rob water of oxygen. Oxygen- poor areas called “dead zones” can appear in both fresh and salt water.Raw sewage also contains microorganisms that can spread disease. 16 Water Quality and Sustainability One key to sustainable water use is to protect the natural systems involved in the water cycle.A watershed includes all the land whose groundwater, streams, and rivers drain into the same place—such as a large lake or river.Sewage treatment can lower levels of sewage-associated bacteriaAgriculture can use integrated pest management (IPM) instead of pesticides.Conserving water is also important. One example of water conservation in agriculture is drip irrigation, 17 Atmospheric Resources The atmosphere, which provides the oxygen we breathe, is a common resource whose quality has direct effects on health.Ozone, a form of oxygen that is found naturally in the upper atmosphere, absorbs harmful ultraviolet radiation from sunlight before it reaches Earth’s surface.The atmosphere’s greenhouse gases, including carbon dioxide, methane, and water vapor, regulate global temperature. 18 SmogSmog is a gray-brown haze formed by chemical reactions among pollutants released into the air by industrial processes and automobile exhaust. Ozone is one product of these reactions.Acid Rain Burning fossil fuels releases nitrogen and sulfur compounds. When those compounds combine with water vapor in the air, they form nitric and sulfuric acids. These airborne acids can drift for many kilometers before they fall as acid rain. 19 Greenhouse GasesBurning fossil fuels and forests releases stored carbon into the atmosphere as carbon dioxide, a greenhouse gas.Agricultural practices release methane, another greenhouse gas.Particulates - Particulates are microscopic particles of ash and dust released by certain industrial processes and certain kinds of diesel engines.Very small particulates can pass through the nose and mouth and enter the lungs, where they can cause serious health problems. 21 The Value of Biodiversity Biological diversity, or biodiversity, is the total of all the genetically based variation in all organisms in the biosphere.What kinds of biodiversity exist, and what value do they offer society? 22 Types of BiodiversityBiodiversity exists on three levels: ecosystem diversity, species diversity, and genetic diversity.Ecosystem diversity refers to the variety of habitats, communities, and ecological processes in the biosphere.The number of different species in the biosphere, or in a particular area, is called species diversity. To date, biologists have identified and named more than 1.8 million species, and they estimate that at least 30 million more are yet be discovered.Genetic diversity can refer to the sum total of all different forms of genetic information carried by a particular species, or by all organisms on Earth. 23 Valuing BiodiversityBiodiversity’s benefits to society include contributions to medicine and agriculture, and the provision of ecosystem goods and services.Biodiversity and MedicineBiodiversity and AgricultureBiodiversity and Ecosystem ServicesThe number and variety of species in an ecosystem can influence that ecosystem’s stability, productivity, and value to humans. Remember the Keystone species? 24 Threats to Biodiversity Species diversity is related to genetic diversity. The more genetically diverse a species is, the greater its chances of surviving disturbances. So as human activity reduces genetic diversity, species are put at a greater risk for extinction.Species diversity is also linked to ecosystem diversity. As ecosystems are damaged, the organisms that inhabit them become more vulnerable to extinction.Humans reduce biodiversity by altering habitats (habitat fragmentation), hunting, introducing invasive species, releasing pollution into food webs, and contributing to climate change. 26 Ecological FootprintEcologists refer to the human impact on the biosphere using a concept called the ecological footprint.The ecological footprint describes the total area of functioning land and water ecosystems needed both to provide the resources an individual or population uses and to absorb the wastes that individual or population generates. 27 Footprint Limitations Calculating actual numbers for ecological footprints is complicated. The concept is so new that there is no universally accepted way to calculate footprint size.In addition, footprints give only a “snapshot” of the situation at a particular point in time. 28 This world map shows each country in proportion to its ecological footprint.
Advanced tube and wing aircraft design illustration The project "Ultra Low emission Technology Innovations for Mid-century Aircraft Turbine Engines", abbreviated "Ultimate" has been running for three years targeted radical concepts for new aero engines, in line with the EU’s long-term emissions reduction target for 2050. The EU is highlighting the project as a success. Could save 3 billion tonnes of CO2 emissions over the first 20 years after 2050 To address this challenge, the ULTIMATE project has developed radical new propulsion concepts that should help the aviation industry meet the targets. The partners have studied how different technologies could be combined to work together in synergy to improve efficiency and reduce emissions. If fully implemented, the engine concepts proposed by the ULTIMATE project could save 3 billion tonnes of CO2 emissions over the first 20 years after 2050. “The technologies combined in our new engine systems benefit one another. This is the first time that the synergies between different radical engine technologies have been explored systematically to create low-emission propulsion engines.” says project lead Tomas Grönstedt of the Department of Mechanics and Maritime Sciences at Chalmers University of Technology. From a long list of possible aero-engine technologies, the ULTIMATE team has focused on those that will work most effectively together. Next, the project team made system models and based on efficiency estimates for each component, they were able to accurately predict how new and existing engine system components would interact and optimise the engine performance cycles. These new jet engines could dramatically improve aircraft efficiency and reduce emissions. They may also be used in novel aircraft designs, with new fuels such as biofuels, hydrogen or methane, and together with turboelectric systems. Radical engine concepts work Grönstedt emphasises the importance of the project outcomes: “Radical improvements to aviation will only happen if the engineering community believes they are possible. Engineers don’t like to introduce unnecessary technical risk and they need to know that improvements can be made economically. The ULTIMATE project has indicated that such engines are feasible, which will help to increase confidence in these radical concepts.”
Discuss how the central nervous system and peripheral nervous system operate. Use a personal example to demonstrate your understanding.© BrainMass Inc. brainmass.com May 20, 2020, 7:53 pm ad1c9bdddf Central Nervous System and Peripheral Nervous System The CNS is the central nervous system that functions in order to coordinate each and every activity taking place in all the parts of the body of every bilaterian organism. The Central Nervous System consists of the brain and the spinal cord. Together with the peripheral nervous system, it has a fundamental role in controlling behavior. The CNS is contained within the dorsal cavity with the brain in the cranial cavity and the spinal cord in the ... The following solution discusses the difference between the Central Nervous System and the Peripheral Nervous System.
The human respiratory system is very complex when compared to other animals as well as in sects. The respiratory system of an amphibian includes the skin that exchanges oxygen and carbon dioxide by process of diffusion through the skin. In case of plants, the respiratory system includes stomata that are found on the underside of the leaves. It is through these stomata that the plants receive their supply of carbon dioxide. The respiratory system in human and all other mammals is made of the lungs, trachea, bronchioles and alveoli. Several molecules of oxygen and carbon dioxide are exchanged with the aid of the alveoli. The process of exchange of gases is known as diffusion. In the humans the environmental gases are transported to the blood circulating in the human body. The oxygen that is inhaled by the respiratory system is converted into energy and the waste [products along with carbon dioxide are exhaled through the lungs into the environment. Ventilation, control of ventilation, inhalation, exhalation and gas exchange are some of the functions of the human respiratory system. There are various diseases affecting the function of the respiratory system and these include bronchitis, asthma, alveolar damage, fibrosis, pulmonary edema, embolism and pulmonary hypertension. Various infections include pneumonia, tuberculosis, exposure to asbestos and other pollutants can also cause anomalies in the normal respiratory function.
For almost seven decades, we've routinely fed antibiotics to the animals we eat. That's just a few years less than we've taken antibiotics ourselves. And for just about as long, it’s been clear that those antibiotic doses have been creating drug-resistant bacteria that pass from meat animals to make humans sick. The first outbreaks of drug-resistant foodborne illness were spotted as early as the mid 1950s, when an epidemic of resistant salmonella swept through southeastern England. That was the first of waves of outbreaks that occurred over decades, some small and some very large and widespread. One of the largest foodborne outbreaks in US history, which made 634 people in 29 states and Puerto Rico sick in 2013-14, was tracked back to chickens that had been given antibiotics in their feed. The connection isn’t universally accepted, of course. Most of the studies linking farm antibiotic use and human illness have been observational, not experimental — and that’s given ag and pharma room to insist that the case against farm antibiotic overuse isn’t solid. The argument has been that the bacterial traffic from animals to meat to humans isn’t proven — and until it can be established with 100 percent certainty, the practice of giving livestock preventative antibiotics should continue. Now a new study, years in the making, goes further than any other to demonstrate that resistant bacteria can move from animals to humans via the meat they become. It also provides a model of how new surveillance systems might reduce that bacterial flow at its source on farms. It’s just one study, but it possesses outsize significance, because it eliminates the uncertainty at the center of that bacterial flow. Outside of experimental conditions, it’s never been possible to prove that this antibiotic given to that animal gave rise to this bacterium that ended up in that human. But this new work dives so deeply into the genomics of bacterial adaptation in food animals and humans, it proves the link that ag would rather deny. Outside of experimental conditions, it’s never been possible to prove that this antibiotic given to that animal gave rise to thisbacterium that ended up in that human. The study was led by Cindy Liu and Lance Price, the chief medical officer and the director of the Antibiotic Resistance Action Center at George Washington University. They began the research in previous roles at the Translational Genomics Research Institute in Flagstaff. That the work was done in Flagstaff is important: It’s a small city without much migration in and out, which made it a self-contained natural laboratory. Every two weeks for a year, they bought meat in Flagstaff’s supermarkets; at the same time, they collected bacteria from the blood and urine of patients in Flagstaff hospitals, and analysed both sets of samples for the presence of resistant bacteria. The idea was to capture the bacteria’s prevalence and create a timeline of when strains arrived and how they spread across the city. If possible, they hoped to prove the strains’ origin and the direction of any spread. There’s an important nuance in the samples Liu and Price chose to collect. Foodborne bacteria — salmonella, campylobacter, shigella — have a self-evident connection to food and farms. But over about two decades, some researchers have become concerned about another bacterial threat that has a less obvious connection to food and a significant public health impact: a specific subset of the vast range of E. coli that have come to be called EXPEC — “extra-intestinal” pathogenic E. coli — because they can escape the gut and cause infections in other parts of the body. The bladder is often the entry portal for EXPECs, so urinary tract infections are often one of the first signs of infection. Untreated UTIs can climb up the urinary tract to the kidneys, and pass from them into the bloodstream — and drug-resistant UTIs are effectively untreated because they don’t respond to the antibiotics given to cure them. EXPECs can also cause more serious illness than foodborne infections, all the way up to septic shock and death. The team took the meat samples and the bacterial isolates back to their lab and looked for organisms that were shared across both sets of samples. They found E. coli, which is a ubiquitous gut-dwelling pathogen, on almost 82 percent of the meat samples and 72 percent of the samples from patients. Among the many strains they found was one known as H22, which was present on chicken meat and in people, and carried genetic markers indicating it had occupied the guts of poultry first, and then adapted to humans. This is what earlier studies of EXPECs on meat and in humans lacked: evidence that meat strains and human infections were linked, not just in time and location, but in movement from animal to person. “I think this is the first time that we can truly establish the direction of transmission,” Price told me. “This shows clearly that people are getting UTIs from E. coli that originate in poultry.” Backing that up, the E. coli strains that crossed from birds to people were more likely than other strains in the samples to be resistant to the antibiotics tetracycline and gentamicin, which are used in poultry production. That affirms the observation, made in hundreds of studies at this point, that antibiotic use on farms creates resistant bacteria that cross to humans. Earlier studies lacked evidence that meat strains and human infections were linked, not just in time and location, but in movement from animal to person. The H22 strains were a tiny subset, about half a percent, of all the strains the team found. Scaled up to the US population, half a percent represents 30,000 to 40,000 cases per year of UTIs and kidney infections — but “the total number is almost certainly much higher,” according to Price, given the other strains that remain to be analyzed. There’s another key detail buried in Liu and Price’s work. They proved the animal-human link by diving deep into the genomics of the strains they recovered; the H22 strains were within a larger group of E. coli strains that aren’t usually associated with animals. Yet outside of academic labs, analyses of foodborne bacteria don’t usually go that deep. They’re not used in the most important federal analysis conducted every year in the United States by the CDC, FDA and USDA, a joint project called the National Antimicrobial Resistance Monitoring System or NARMS. The NARMS project looks for foodborne bacteria that have become antibiotic-resistant affecting humans, traveling on meat, and present in animals when they come to slaughterhouses. Every year it shows which types of meat are more likely to be carrying resistant bacteria and how multi-drug resistant the bacteria are. Because the meat is bought in retail stores, the labels on the packages can link the meat back to the processors it came from; in fact, those labels have been used in the past to solve foodborne outbreaks that stretched country-wide. As it stands, the NARMS system does a certain amount to identify where foodborne threats to health are coming from — but that data begins at the point at which animals enter the system to become the meat that processors sell. NARMS’ access to slaughterhouses is limited, and the USDA has fought unsuccessfully for years to be allowed to sample meat animals while they’re still on the farms where they were grown. If that access were expanded, and combined with both the existing label data and the fine-grained analysis that Liu and Price conducted in their labs, the result could be a monitoring system that would do much more to protect our food. Currently, surveillance illuminates the threats that are headed toward American consumers from the meat that is about to land on their plates. But a higher-resolution surveillance system could give us a view that goes from the plate all the way back to the farm, and maybe even to individual flocks that are harboring hazardous strains of bacteria. A system that fine-grained is a hope, not a present reality — but it’s the direction we should move in, if we want our meals to be safe. More Great WIRED Stories - Inside the haywire world of Beirut's electricity brokers - Is it possible to find love without dating apps? - How to get the most out of Gmail’s new features - Could Crispr soon halt muscular dystrophy in humans? - How NotPetya, a single piece of code, crashed the world - Looking for more? Sign up for our daily newsletter and never miss our latest and greatest stories
Early opposition to the First World War in England was scattered and ineffective – the various opponents had no time to get co-ordinated because of the speed with which the war was declared. The British Neutrality League led by Norman Angell, the British Neutrality Committee, the Labour Party, and others all dissented but to no avail. In addition to the two case studies of war resistance presented here, there are also two related case studies which have been placed under the theme Women for Peace: Claire Culhane: Canadian Peace Activist and Humanitarian and Working for Peace: Eva Sanderson and the Toronto Association for Peace. Culhane’s experiences as a nurse in Vietnam turned her an active campaigner against the War. Sanderson led the vocal TAP campaign against the Vietnam War. The Vietnam War (1961-1975) caused protest movements around the world. The struggle for Vietnamese independence against the French had begun in 1946. That phase of the conflict came to an end in 1954 with the partition of Vietnam into North (controlled by Communists) and South. The next phase of the struggle was the push for unification, led by Ho Chi Minh from the North. The involvement of the Americans, opposed to Communist expansion, began with the sending of a small number of troops to the South in 1961 and the American presence escalated every year after that.
Melvyn Bragg and guests discuss the history of the discovery of radiation, from the idea that light consisted of waves, through electromagnetism to the naming of gamma rays. Melvyn Bragg and guests Jim Al-Khalili, Frank Close and Frank James discuss the history of the discovery of radiation.Today the word 'radiation' conjures up images of destruction. But in physics, it simply describes the emission, transmission and absorption of energy, and the discovery of how radiation works has allowed us to identify new chemical elements, treat cancer and work out what the stars are made of.Over the course of the 19th century, physicists from Thomas Young, through Michael Faraday to Henri Becquerel made discovery after discovery, gradually piecing together a radically new picture of reality. They explored the light beyond the visible spectrum, connected electricity and magnetism, and eventually showed that heat, light, radio and mysterious new phenomena like 'X-rays' were all forms of 'electromagnetic wave'. In the early 20th century, with the discovery of radioactivity, scientists like Max Planck and Ernest Rutherford completed the picture of the 'electromagnetic spectrum'. This was a cumulative achievement that transformed our vision of the physical world, and what we could do in it.Jim Al-Khalili is Professor of Theoretical Physics and Chair in the Public Engagement in Science at the University of Surrey; Frank Close is Professor of Physics at Exeter College, University of Oxford; Frank James is Professor of the History of Science at the Royal Institution.
Loss of tooth structure or the whole tooth in primary dentition generally occurs due to dental caries or trauma to the tooth. Damage to the tooth pulp can affect the development of permanent teeth as well. We often tend to remove the affected tooth in children as it is common in thinking that the tooth will fall off sooner or later. But saving the teeth of children is just as important as it is for elders. A dentist can examine and advise the best possible treatment for a tooth after reviewing it. However, saving a tooth and pulp tissue by root canal treatment is now a common practice. Let’s have a look at look why saving the tooth is critical for a child. - Teeth add in mastication. - Present primary teeth will guide the succedaneous teeth. - Help to prevent psychological effects associated with loss of primary teeth. - Loss of tooth will cause an aberrant tongue habit. - Saving a tooth will prevent possible speech issues. - And, of course, it maintains aesthetics. Early loss of primary teeth can lead to the delayed eruption of the permanent teeth. Sign and Symptoms for Root Canal Treatment Your family dentist will review your child’s complete history as a general disease will require different treatment. They will also want to know if your child has had previous infections. When the tooth pulp is damaged the following sign occurs. - Pain in the tooth. It may be sharp or dull. - Sensitivity to hot and cold while eating. Redness and swelling in that area on the gum tissue. Some children may not experience swelling because there could be a pimple-like sac present that drains the pus. But children will get a persistent bad taste in the mouth. - Discoloration of the tooth. - Unexpected or premature loss of a tooth. - Diagnostic tests and X-rays Diagnostic X-rays are vital as they provide actual footage of the inside of the tooth. Dentists will perform several other tests to observe the vitality of the tooth. They will check for pain in the tooth by tapping the tooth with the help of specific dental instruments. On taping an affected tooth, there should be a level of pain. In a perfectly sound tooth, no discomfort will occur when the tapping is performed. Dentists will also check for temperature sensitivity by applying hold and cold stimulus on the tooth. A problematic tooth will react with pain when the stimulus is applied. An electric pulp test is another performed experiment to again, check the vitality of the suspected infected tooth. The electric tester will pass a mild current through the tooth and patient will feel tingling in the tooth. If the patient does feel tingling in the tooth, then it means that the tooth is vital. Otherwise, it is non-vital. Paediatric Pulp Treatment Pediatric pulp therapy is mostly performed to save the infected and damaged primary tooth. It is very important to save the primary teeth as they will guide the permanent teeth into the designated spaces and can help them to break through. Pulp saving treatment is of two types. 1 – Pulpotomy In Pulpotomy, the partial pulp is removed from the crown and pulp chamber which is infected. Leaving the healthy pulp in the root canals. After the removal of the infected pulp from the chamber, the tooth is filled with a disinfecting agent to prevent any further infection. If the crown is not affected that much, then the tooth structure is restored with a filling. Otherwise, a crown can be placed over the top. 2 – Pulpectomy In pulpectomy, all of the pulp in the pulp chamber as well as in the root canal is infected and requires removal. This procedure is not painful. It is performed by giving local anesthesia so that the child will not feel any pain. After the removal of all the infected and necrotic pulp from the tooth and the root canal, a dressing, usually zinc-oxide eugenol as well as mineral trioxide aggregate, is placed in the tooth for several days. If the tooth is no longer painful, then it is sealed with an absorbent material and restored further with a regular filling or by placing the metal crown. Why Root Canal Is a Choice Over Extraction The Question of Why Performing a Root Canal in Baby Teeth Is Important? Extraction of the infected or painful tooth is not a good option. With altered mastication and aesthetics, it creates alternative consequences as well. When the tooth is extracted or removed, the adjacent teeth move from their designated place to cover the space that’s created by the removal of the tooth. This prompts a change in the angle of the teeth. The leading permanent teeth find it challenging to erupt in their proper place and so impaction can occur. Depending on the location of the missing tooth, aesthetic is also affected. Compromised aesthetics can cause psychological problems in young children. Root canal treatment sounds like a very painful and tiring procedure. Maybe some people feel fear by hearing the words root canal treatment, but it is perhaps due to the lack of knowledge and other horror stories. If you consult a dentist, they can assure you of the importance of saving the natural tooth. There is no alternative to a natural tooth. No one can advise you better than a dentist can when it comes to the extraction or restoration of a tooth. There is nothing quite as comforting as seeing your little one growup happy and healthy. What Happens If the Tooth Is Left Untreated? If an infected tooth is ignored and left untreated, the infection can spread to the nearby, surrounding tissue and the underlying bones as well. It can lead to severe pain, abscess formation, and even life-threatening infections. Regular checkups and routine visits to the dentist will educate you about your little one’s dental health and all of the happenings occurring inside the mouth. It is a huge relief if the problem is diagnosed early. It will not only be helpful for the dentist to catch the underlying cause, but also the child will not suffer from pain and other discomforts anymore. There is no such pleasure and happiness than to see your child smile and grow healthily. And one way in which you can do this is by helping them maintain good oral health! Relate Posts to Read: Do Baby Teeth Have Roots? And Other FAQs
Now we will consider the four basic operations with whole numbers: addition, subtraction, multiplication, and division. Adding Whole Numbers Addition means putting things together. The numbers to be added are called the addends. The total is called the sum. The digits are aligned in columns to ensure that like terms are added. First we add all the numbers in the ones place, then we add all the numbers in the tens place, and so on. Example: You will need to carry a number whenever the sum of the addends is greater than nine. Example: Usually, we write the numbers in a column format with ones, tens, hundreds, etc. aligned, then add each column beginning with the ones, and carry-over digits to the left. Word Problems – Using Whole Numbers WN04 Adding Whole Numbers 1 WN05 Adding Whole Numbers 2 WN06 Find the Missing_Addends Write your own word problem:
...the worrisome plight of smallmouth bass foretells broader problems downstream if left uncorrected." Smallmouth bass are loved by anglers because they are spectacular fighters. When hooked, these bronze freshwater fish with red eyes and stripes tend to leap high out of the water and thrash with the power of fish several times their size. Also called "bronzebacks," they favor faster-moving, rocky, cooler, upstream sections of rivers, and so are often pursued by outdoors enthusiasts in waders, kayaks, canoes, and shallow-bottomed boats. Smallmouth bass are not native to the Chesapeake Bay region; they are originally from the Mississippi River basin and Great Lakes. (Wait a minute. If smallmouth bass aren't native why are we trying to save them? Keep reading.) During the 19th century, the fish were stocked in rivers across the U.S., often by federal and state fish commissions, because smallmouth were regarded as a desirable game species. In 1854, smallmouth bass were carried from the Ohio River in the water tank of a train and released into the Chesapeake & Ohio Canal, where they multiplied and spread into the Potomac and connecting rivers. Smallmouth were introduced to the Susquehanna River in 1869, the James River in 1871, and the Patuxent River in 1897. Today, smallmouth bass comprise a $630-million industry across the Bay watershed states. Along with their bigger counterparts, largemouth bass—which are also non-native to the Chesapeake Bay region, smallmouth bass are considered an exotic species, not an invasive species. The latter designation means the species kills off native species and causes harmful levels of competition for resources. Exotic species, like earth worms and bumble bees, exist in harmony with native species. Canary in the Coal Mine or Why We're Concerned About a Non-native Species Smallmouth bass do not tolerate pollution well, which makes them an indicator of water quality. Some fisheries biologists suggest that smallmouth bass may be like the "canary in the coal mine," indicating possible future health problems with other species of fish. High levels of nitrogen and phosphorus pollution, rising water temperatures, and chemical contaminants may have combined to weaken the immune systems of smallmouth bass and make them more susceptible to naturally occuring bacteria, viruses, and parasites. Those pollutants may start in fresh water rivers, but they continue downstream, contributing to the nitrogen, phosphorus, and contaminant problems plaguing the Chesapeake Bay. Over the last decade, this prized freshwater sport-fish species has suffered fish kills and perplexing illnesses in several Bay tributaries. These tributary rivers include the South Branch of the Potomac River in West Virginia, the Shenandoah and Cowpasture Rivers in Virginia, the Monocacy River in Maryland, and the Susquehanna River in Pennsylvania. Problems with the fish have included lesions, blotchy skin, wart-like growths, excessive mucus covering their bodies, lethargic behavior, and abnormal sexual development in which males grow eggs in their testes. In the Susquehanna River, smallmouth bass populations have plummeted, with catch rates of adults falling 80 percent between 2001 and 2005 in some areas. According to the Pennsylvania Fish and Boat Commission, the population has not recovered. In 2012, this dramatic decline prompted the state agency to impose emergency regulations that prohibit fishing for the species in much of the river from May 1 to June 15. This ban in the Susquehanna River—the largest source of fresh water to the Chesapeake Bay—will continue in 2013. While more study into the causes of the fish kills and illnesses is required, one fact is clear. To restore populations of smallmouth bass, as well as the health of the Chesapeake Bay and its rivers and streams, we must reduce nitrogen and phosphorus pollution. Of the myriad of contributing factors, this is one factor that people can easily control. And addressing the problem will help sustain the economic benefits of smallmouth bass. Cutting back nitrogen and phosphorus pollution will help reduce stress on smallmouth bass and other fish. Reducing pollution will also further efforts the Bay states—New York, Pennsylvania, Maryland, Delaware, Virginia, and West Virginia—and the District of Columbia are making to meet mandatory limits on pollution entering the Chesapeake Bay. In 2010, EPA established science-based limits for nitrogen, phosphorus, and sediment pollution and allocated reduction targets to each state. The states then developed and now are beginning to put into effect plans that should restore clean water sufficiently to remove the Bay from the notorious Clean Water Act 'dirty waters' list (of section 303[d] of the act). The plans must be in place by 2025. Together the limits and the states' plans are the Clean Water Blueprint for the Chesapeake and its rivers and streams. The Bay states are making good progress already. But the story of the smallmouth bass reminds us that the job is far from done. The good news is that as we accelerate implementation of the Blueprint, we can expect healthier fishing and swimming, the creation of thousands of jobs, and a proud legacy of restoration for our children and grandchildren. Truly, we find ourselves at the moment in time for the Bay.
Cluster sees tsunamis in space Cluster is providing new insights into the working of a ‘space tsunami’ that plays a role in disrupting the calm and beautiful aurora, or Northern Lights, creating patterns of auroral dances in the sky. Generally seen in high-latitude regions such as Scandinavia or Canada, aurorae are colourful curtains of light that appear in the sky. Caused by the interaction of high-energy particles brought by the solar wind with Earth’s magnetic field, they appear in many different shapes. Early in the evening, the aurora often forms a motionless green arc that stretches across the sky in the east-west direction. Colourful dancing auroral forms are the results of disturbances known as ‘substorms’ taking place in Earth’s magnetosphere. These perturbations can affect our daily lives, in particular by affecting the reception of GPS signals. Thus, understanding the physical processes involved is important to our routine life and security. These substorms typically last one to two hours and are three-dimensional physical phenomena spread over altitudes from 100 to 150 000 kilometres. Trying to understand such complex physical processes with a single scientific spacecraft is like trying to predict the behaviour of a tsunami with a single buoy in an ocean. That is why the simultaneous use of several satellites, like the Cluster constellation, is necessary to understand these events. Currently, there are two competing theoretical models to describe these substorms or space tsunamis. The first one is called the ‘Current-Disruption’ model, while the second one is the ‘Near Earth Neutral Line Model’. Using data from the four Cluster spacecraft, a group of scientists from both sides of the Atlantic were able to confirm that the behaviour of some substorms is consistent with the Current Disruption model. A substorm develops and builds up in different stages, and it is the detailed study of one of these stages that helps us to understand which of the two models apply. For example, in the late stage of substorm development, auroral disturbances move towards the poles, suggesting that the energy source for auroras and substorms moves away from Earth. Previous satellite observations have found that, during this late stage, the flows of plasma (a gas of charged particles populating Earth’s magnetosphere) in the magnetotail exhibit a reversal in direction. In recent years it was generally thought that a flow reversal region is where magnetic reconnection takes place, that is where the energy of the magnetic field is converted into particle energy (dissipation effect), resulting in high-speed plasma flows that hurl towards Earth, like space tsunamis. Detailed analysis of data obtained by the Cluster satellites while crossing such a region in the magnetotail, where flows of plasma exhibit a reversal in direction, has been reported by the team of Dr Tony Lui, a scientist of the Applied Physics Laboratory at the John Hopkins University, Maryland, USA, Co-Investigator of the Research with Adaptive Particle Imaging Detectors (RAPID) high-energy particles experiment on Cluster, and lead author of the study. Thanks to the unique capability of Cluster to perform simultaneous multipoint measurements, the scientists were able to derive several physical parameters never before estimated for such a flow reversal region. By comparing the directions of the electric current and the electric field in the magnetosphere it is possible to understand whether the cause of the flow reversal is a dissipation effect (where magnetic field energy converted to particle energy) or a dynamo effect (where particle energy is converted to magnetic field energy). For this case study, the Cluster scientists observed that features associated with flow reversal are actually very complex, consisting of both dissipation and dynamo effects in localised sites. This result shows that the plasma turbulence disrupts the local electric current. “The features we observed are consistent with the current disruption model. However, it is unclear how general these findings are. More events will be examined in the future," said Dr Lui. "The magnetic substorm phenomenon is a hot topic of research,” added Philippe Escoubet, Cluster and Double Star project scientist for ESA. “This new Cluster result will certainly contribute to the on-going scientific debate and foster research cooperation with scientists involved in the newly launched NASA Time History of Events and Macroscale Interactions during Substorms (THEMIS), a mission specifically dedicated to studying substorms.” Notes for Editors The findings appear in the paper, “Cluster observation of plasma flow reversal in the magnetotail during a substorm”, published in Annales Geophysicae 9 August 2006. Lui, A. T. Y., Y. Zheng, Y. Zhang, H. Rème, M. W. Dunlop, G. Gustafsson, S. B. Mende, C. Mouikis, and L. M. Kistler For more information Tony Lui, JHU/APL, USA Email: tony.lui @ jhuapl.edu Philippe Escoubet, ESA Cluster Project Scientist Email: philippe.escoubet @ esa.int
IELTS Writing Skills: What is the examiner looking for? IELTS Writing Skills Students can feel they fail to progress with their writing, often because they are unsure of what the examiner is looking for. This is the purpose of the Public Band Descriptors for Task 1 and Task 2 – to inform you about what the examiner assesses in your writing, and what you need to do to reach your target band. For Task 2, to reach the band you need, the first area to work on is Task Response – ensuring that you answer the question fully and appropriately. Many students, however, get a low score for Task Response, as they are unclear what they are being asked to do. What do the Public Band Descriptors say? The Descriptors are available online. To reach the band you need – for most students this is a 7.0 – you are given the following guidelines. For Task 2, a student with a 7.0: - ‘addresses all parts of the task - presents a clear position throughout the response - presents, extends and supports main ideas, but there may be a tendency to overgeneralise and/or supporting ideas may lack focus’ What does this mean? It is important that you understand what this means. If we paraphrase, they mean that in Task 2, a student who gets a 7.0: - covers all parts of the question - makes their opinion clear throughout the essay, i.e. in all paragraphs - provides support, i.e. reasons, examples, results There is a fourth important thing to remember. This student also: - writes more than 250 words Can I see an example? Let’s consider the following Task 2 question: Large numbers of children and young people use technology in schools. To what extent do you think that technology has a beneficial effect in schools? Look at the following model introduction: As using computers and programs such as Word and Excel has become a key part of working life, it becomes increasingly important for teachers to ensure their pupils have a high level of digital literacy. The use of technology in the classroom, in my opinion, ensures young people acquire key skills for both work and their future studies. In this short introduction, the candidate already manages to do many things asked by the examiner: - Covers all parts of the question: The candidate directly discusses the effects of technology on education. They avoid being too general – a common mistake is to write several sentences about technology in general: i.e. ‘Nowadays people have computers all over the world.’ The candidate gets straight to the point, and they discuss digital literacy instead of technology in general. - Makes their opinion clear throughout the essay: We know exactly what the candidate thinks about technology in schools: digital literacy is important, and technology ensures young people acquire key skills. They make it clear that this is their position by saying in my opinion. A common mistake is to state no opinion until the conclusion – this candidate has not made this mistake! - Provides support, i.e. reasons, examples, results: This is only an introduction, so the candidate has avoided providing any support. The support will follow in the body paragraphs. There are signs from the introduction that this candidate will be highly successful, as they discuss the topic directly and make their opinion clear. - Amandine and Claudia were both at Live Language... - Live Language, Glasgow’s leading language schoo... - As we are sure you have heard, the UK is very l... - What is it? In this part of the Use of English ... - FCE Academy – http://fceacademy.com/ The ...
Botswana, Land and Resources Makgadikgadi Pan, Boteti River, Okavango River, Savanna vegetation, hippopotamuses Most of Botswana is a tableland with an average elevation of about 1,000 m (about 3,300 ft). The Kalahari Desert covers the central and southwestern portions of the country. The principal stream is the Okavango River, which flows southeast from the Angola highlands into northwestern Botswana and drains into the Okavango Delta (Okavango Swamp), where it forms a vast marshland. During the rainy season the flow continues east on the Boteti River to Lake Xau and the Makgadikgadi Pan. The southern part of the country has no permanent streams. In general, Botswana has a semiarid subtropical climate. The average annual rainfall varies from about 640 mm (about 25 in) in the north to less than 230 mm (less than 9 in) in the Kalahari. Rainfall is concentrated in the summer months (December to April). Precipitation, however, is undependable, and the country is subject to drought. Savanna vegetation predominates in most parts of Botswana, and consists of grasslands interspersed with trees. Principal species include acacia, bloodwood, and Rhodesian teak. Wildlife is abundant in Botswana and includes lions, giraffes, leopards, antelope, elephants, crocodiles, and ostriches. Mineral resources include diamonds, copper, nickel, coal, cobalt, manganese, soda ash, asbestos, and salt. Environmental problems include overgrazing of the land and desertification. Precipitation is irregular, and the country is prone to drought. A large irrigation and water storage project was planned for the northern part of the country during the 1980s, but environmental concerns and popular opposition led to the suspension of the project in 1992. Botswana has designated 18.5 percent (1997) of its land as parks and reserves, giving it the highest percentage of protected land in any African country. The Okavango Delta is one of the largest inland deltas in the world and provides habitat for elephants, zebras, giraffes, hippopotamuses, and crocodiles. The country is inhabited by 550 bird species. Botswana has ratified international agreements protecting endangered species and the ozone layer. The country has also signed treaties limiting trade in endangered animal species. Article key phrases:
What is Classical Education? Classical education has its roots in the teaching methods of the ancient Greeks. It was the primary educational model of the Western world until the twentieth century. Each subject area is taught through the classical threesome, or “trivium,” that corresponds to children’s developmental levels at each stage. “Grammar” (preschool/elementary school age) is focused on basic knowledge, acquisition, and structure not only of language but also any field of study. “Logic” (middle school age) is the analysis of cause and effect relationships in an area of study. “Rhetoric” (high school and beyond) is persuasive and creative communication of knowledge, skill, and ideas. These areas of the trivium not only correspond to grade levels, but can be incorporated into every level of learning. In addition, since we are a Christian school, the Bible is taught to the children as fundamental truth through which we understand all subjects. “[Classical education] emphasizes the goal of giving our children the educational tools to both learn and think for themselves” -Gregg Strawbridge, Classical and Christian Education How does this impact the way we teach? Children in the grammar stage of learning memorize and respond to new knowledge easily. They retain a repertoire of essential knowledge and skills for future use. For students in our classical primary school, one can expect the following: - Creative, yet structured and sequential teaching within the grade level and between grade levels - Enjoyment of literature, music, and art from many time periods and genres - Reading lessons based on quality or classic children’s literature - Thorough memorization of phonics, math facts, English rules, history etc. - Drills that incorporates singing, movement, and recitation - Learning through singing, drama, and second language - Multi-sensory exploration - Bible instruction that builds faith and knowledge - Integration of all subject matter
There are three different types of retinal detachment: Rhegmatogenous [reg-ma-TAH-jenous]—A tear or break in the retina allows fluid to get under the retina and separate it from the retinal pigment epithelium (RPE), the pigmented cell layer that nourishes the retina. These types of retinal detachments are the most common. Tractional—In this type of detachment, scar tissue on the retina's surface contracts and causes the retina to separate from the RPE. This type of detachment is less common. Exudative—Frequently caused by retinal diseases, including inflammatory disorders and injury/trauma to the eye. In this type, fluid leaks into the area underneath the retina, but there are no tears or breaks in the retina.
Blood forms 7% of a person's body weight and its volume may vary from one individual to another depending on the size. It is the life-maintaining fluid that circulates through the entire body, via blood vessels called arteries and veins. Blood plays a vital role in our existence as it carries oxygen, nourishment, vitamins, hormones, antibodies, heat and electrolytes to different parts of the body, which are essential for the body's proper functioning. They also carry and get rid of carbon dioxide and waste matter from the blood. The human blood is made up of 78% water and 22% solids. Blood contains plasma in which blood cells such as red blood cells (RBC), white blood cells (WBC) and blood platelets are suspended. All these components play very important roles in the body, however, in this article we will only focus on the function of red blood cells. What are the Functions of Red Blood Cells Red blood cells or RBCs are also referred to as erythrocytes and are the most abundantly found blood cells as compared to WBCs and platelets, accounting for about 45% of total blood volume. They are around 6 - 8 micrometers in size and the human body contains about 4 - 6 millions/mm3 of them. RBCs are biconcave lens-like cells that lack a cell nucleus and are made up of a protein called hemoglobin. In fact, 33% of RBC is nothing but hemoglobin. Embedded within this hemoglobin molecule is iron, whose function is to transport oxygen and carbon dioxide in the blood. This hemoglobin is also responsible for the biconcave shape and red color of the RBCs. RBCs are formed in the bone marrow, under the influence of hormone erythropoietin (formed in the kidneys), by a process called erythropoiesis, in just 7 days. On maturing in the bone marrow, these cells are circulated in the body for almost 3 months before they are destroyed in the spleen, or recycled by the macrophages in the body. So the general lifespan of a red blood cell is only 3 months. Well, so what does the red blood cell do in its short lifespan and why is it so important for our existence? To understand this, we will have to look at some red blood cell functions. The main function of the red blood cell is to transport oxygen from the lungs, to the other tissues and cells of the body. And how does the RBC manage to do this? Well, the hemoglobin present in the RBC is a protein, which binds itself to the oxygen molecules inhaled. When a person inhales, oxygen from the atmosphere enters the body through the nostril and reaches the lungs. At the lungs, hemoglobin molecules bind themselves to the oxygen molecules and move to the heart. From the heart, the same oxygen-containing blood is pumped to the rest of the body parts (muscles, tissues and other organs). The hemoglobin molecules then release the oxygen molecules to the cells of the body. Basically, hemoglobin takes oxygen from high oxygen level areas and releases them in low oxygen level areas of the body. Thus, RBCs actually perform the function of transporting life-sustaining oxygen to the different parts of the body. Carries Carbon Dioxide The other function of the red blood cell is to partly carry carbon dioxide, which is a waste product of metabolic activities in the body. Carbon dioxide is actually formed in the cells as a result of the chemical reactions taking place. This waste product is then excreted through the blood plasma and RBCs. While the RBCs play a major role in eliminating carbon dioxide from the cells, blood plasma also accounts for a small amount of carbon dioxide removal. The hemoglobin in the RBCs bind the carbon dioxide molecules to form carbaminohaemoglobin. However, unlike oxygen molecules, carbon dioxide molecules do not bind to the iron part of hemoglobin. Instead, they combine with the amino acid groups on the hemoglobin polypeptide chains. Thus, RBCs transport carbon dioxide from the various cells of the body and take them to the lungs, from where it is discarded by exhalation. This round trip of transporting oxygen to the tissues and then bringing waste materials to the lungs for elimination, takes the RBCs only 30 to 45 seconds. The ability of the RBC to transport oxygen depends on several factors like pH of the blood, temperature, etc. Moreover, the presence of carbon monoxide, hydrogen sulfide, etc. in the blood also affects hemoglobin's oxygen carrying capacity. The exact process of oxygen transfer from the hemoglobin to the tissues of the body is a complex one. However, this was a simple way of explaining the function of red blood cells. Don't be fooled by the easy explanation and think that the RBC does nothing of great significance. If at all these RBCs stop functioning, then the body will surely have life-threatening issues. Blood disorders like sickle-cell anemia, hemolytic anemia, hemochromatosis, hereditary spherocytosis and various other red cell enzyme deficiencies can occur and pose a threat to one's life.
Analyzing a novel The message and other contexts It is one thing to tell what the story is in a novel and to give an in-depth presentation of it. Different readings can be applied on a novel, for example a biographical, a comparative or a historical. “The message” is what is told between the lines so to say. Example 1: The message could be political as in the poem “Howl” by Allen Ginsberg. “who passed through universities with radiant cool eyes hallucinating Arkansas and Blake-light tragedy among the scholars of war, / who were expelled from the academies for crazy & publishing obscene odes on the windows of the skull” This is not explicit political neither is the political far from the only force behind the expression. The political substance is partly implicit in the way the voice in the poem pride the individual and especially the outsider. The outsider-theme is extremely common in literature and is often in concurrence with a political stance. Example 2: The message could be moral as in the novel Pride and Prejudice by Jane Austen. Many would describe Austen’s novel Pride and Prejudice as a love story between the characters Elizabeth and Mr. Darcy. This is not wrong at all, but I may not be the message of the story that is told. For example, you could look at it a lesson in moral. The youngest sister Lydia is from a moral perspective contrasted to Elizabeth and it is easy to understand there the sympathy from the writer lays. Among the major things to consider in an analysis is if a specific theme could be found. It is very probable since the themes are many and in different areas. You have the knowledge of plenty of themes in literature even if you perhaps aren’t aware of it. For example, in the science fiction genre, common themes are speculation about the future, dystopian scenarios and life on other planets. Example: How does a science fiction novel correspond to typical themes in its genre? This is a simple but solid approach to an examination of a novel or motion picture. Does the novel include a speculation of a distant future? If yes, the follow-up question to put: does the speculations mirror the contemporary world–this is often the case. If yes, the next follow-up question to put: does is doing this in a critical way? Depending on the fashion in the critic of literature, the willingness to involve the author from a biographical perspective, tends to shift. Yet, an important key to a specific literature work can often be found be compare it with the life of the writer. It is not always the case that such comparisons must be of interest, but it is indeed very tempting to search for clues in that direction. Some novels insist on some research into the life of the person behind the novel. Example: How does the protagonist in My Struggle related to the writer Karl-Ove Knausgård? The six novels that makes up My Struggle (Min kamp) is among the most notice novels in recent years. The book was controversial, not at least in Norway, the home country of the writer, since it involves real persons (and sometimes with their real names). The writing technique is in this case reflected in the content. The writing is partly hyper-realistic and the reader get the expression that the depicted events in the book must been taken from real life. The interesting thing is though that the book involves a lot a fiction after all, which is partly a method to give it a composition. The historical context The context should always be a thing to think about when analyzing a novel or a poem. The context is already mention indirectly since it can be a part of both the message and the biographical perspective. Another way is to contribute a work to a specific context, in this case an historical. Example 1: How could a Robinson Cruse reading with an historical context in mind look like? Robinson Cruse is one of the most famous novels of all time. Almost everyone knows a little about the story, but few can place the story in a historical context. This could be a great starting point for an analyze of this novel. Example 2: How does the patriotism vary in novels during and after World War II? To set up an issue or a question is a great way to breed a literature analyzes. You will automatically find yourself in a reading that is beyond consuming the story. A very noticeable tendency occurred during the World War II. Many books and motion pictures were produced in the war genre and they displayed often an obvious patriotic agenda. This leads into another question how art can affect people. In this case you could involve two works in your analyze and make a comparison how patriotic elements were present in two different books, one that was written during the war and one written afterwards.
“When NASA’s Juno spacecraft flew past Earth on Oct. 9, 2013, it received a boost in speed of more than 8,800 mph (about 7.3 kilometer per second), which set it on course for a July 4, 2016, rendezvous with Jupiter. One of Juno’s sensors, a special kind of camera optimized to track faint stars, also had a unique view of the Earth-moon system. The result was an intriguing, low-resolution glimpse of what our world would look like to a visitor from afar. The cameras that took the images for the movie are located near the pointed tip of one of the spacecraft’s three solar-array arms. They are part of Juno’s Magnetic Field Investigation (MAG) and are normally used to determine the orientation of the magnetic sensors. These cameras look away from the sunlit side of the solar array, so as the spacecraft approached, the system’s four cameras pointed toward Earth. Earth and the moon came into view when Juno was about 600,000 miles (966,000 kilometers) away — about three times the Earth-moon separation. During the flyby, timing was everything. Juno was traveling about twice as fast as a typical satellite, and the spacecraft itself was spinning at 2 rpm. To assemble a movie that wouldn’t make viewers dizzy, the star tracker had to capture a frame each time the camera was facing Earth at exactly the right instant. The frames were sent to Earth, where they were processed into video format. “ Video and text via NASA Jet Propulsion Laboratory.
(The General Theory of Evolution, as acknowledged by prominent evolutionists, includes the origin of life; see introduction to Origin of life.) How did life originate? Evolutionist Professor Paul Davies admitted, “Nobody knows how a mixture of lifeless chemicals spontaneously organized themselves into the first living cell.”1 Andrew Knoll, professor of biology, Harvard, said, “we don’t really know how life originated on this planet”.2 A minimal cell needs several hundred proteins. Even if every atom in the universe were an experiment with all the correct amino acids present for every possible molecular vibration in the supposed evolutionary age of the universe, not even one average-sized functional protein would form. So how did life with hundreds of proteins originate just by chemistry without intelligent design? See: How did the DNA code originate? The code is a sophisticated language system with letters and words where the meaning of the words is unrelated to the chemical properties of the letters—just as the information on this page is not a product of the chemical properties of the ink (or pixels on a screen). What other coding system has existed without intelligent design? How did the DNA coding system arise without it being created? See: Thanks to “Cowboy Bob” Sorensen for this ‘YouTube’ version of the 15 questions brochure. How could mutations—accidental copying mistakes (DNA ‘letters’ exchanged, deleted or added, genes duplicated, chromosome inversions, etc.)—create the huge volumes of information in the DNA of living things? How could such errors create 3 billion letters of DNA information to change a microbe into a microbiologist? There is information for how to make proteins but also for controlling their use—much like a cookbook contains the ingredients as well as the instructions for how and when to use them. One without the other is useless. See: Meta-information: An impossible conundrum for evolution. Mutations are known for their destructive effects, including over 1,000 human diseases such as hemophilia. Rarely are they even helpful. But how can scrambling existing DNA information create a new biochemical pathway or nano-machines with many components, to make ‘goo-to-you’ evolution possible? E.g., How did a 32-component rotary motor like ATP synthase (which produces the energy currency, ATP, for all life), or robots like kinesin (a ‘postman’ delivering parcels inside cells) originate? Why is natural selection, a principle recognized by creationists, taught as ‘evolution’, as if it explains the origin of the diversity of life? By definition it is a selective process (selecting from already existing information), so is not a creative process. It might explain the survival of the fittest (why certain genes benefit creatures more in certain environments), but not the arrival of the fittest (where the genes and creatures came from in the first place). The death of individuals not adapted to an environment and the survival of those that are suited does not explain the origin of the traits that make an organism adapted to an environment. E.g., how do minor back-and-forth variations in finch beaks explain the origin of beaks or finches? How does natural selection explain goo-to-you evolution? See: Everyone recognizes design in a glass vase, but evolutionists refuse to believe that the flowers in the vase must also have been designed. The problem is not that they do not show design, but that they show too much design. How did new biochemical pathways, which involve multiple enzymes working together in sequence, originate? (This video simply explains the concept of a short biochemical pathway.) Every pathway and nano-machine requires multiple protein/enzyme components to work. How did lucky accidents create even one of the components, let alone 10 or 20 or 30 at the same time, often in a necessary programmed sequence. Evolutionary biochemist Franklin Harold wrote, “we must concede that there are presently no detailed Darwinian accounts of the evolution of any biochemical or cellular system, only a variety of wishful speculations.”3 See: Living things look like they were designed, so how do evolutionists know that they were not designed? Richard Dawkins wrote, “biology is the study of complicated things that have the appearance of having been designed with a purpose.”4 Francis Crick, the co-discoverer of the double helix structure of DNA, wrote, “Biologists must constantly keep in mind that what they see was not designed, but rather evolved.”5 The problem for evolutionists is that living things show too much design. Who objects when an archaeologist says that pottery points to human design? Yet if someone attributes the design in living things to a designer, that is not acceptable. Why should science be restricted to naturalistic causes rather than logical causes? See: How did multi-cellular life originate? How did cells adapted to individual survival ‘learn’ to cooperate and specialize (including undergoing programmed cell death) to create complex plants and animals? See: How did sex originate? Asexual reproduction gives up to twice as much reproductive success (‘fitness’) for the same resources as sexual reproduction, so how could the latter ever gain enough advantage to be selected? And how could mere physics and chemistry invent the complementary apparatuses needed at the same time (non-intelligent processes cannot plan for future coordination of male and female organs). See: Photo by Joachim Scheven The horseshoe crab is one of thousands of organisms living today that show little change from their ‘deep time’ fossils. In the supposed ‘200 million’ years that the horseshoe crab has remained unchanged (no evolution), virtually all reptiles, dinosaurs, birds, mammals and flowering plants have supposedly evolved. Why are the (expected) countless millions of transitional fossils missing? Darwin noted the problem and it still remains. The evolutionary family trees in textbooks are based on imagination, not fossil evidence. Famous Harvard paleontologist (and evolutionist), Stephen Jay Gould, wrote, “The extreme rarity of transitional forms in the fossil record persists as the trade secret of paleontology”.6 Other evolutionist fossil experts also acknowledge the problem. See: How do ‘living fossils’ remain unchanged over supposed hundreds of millions of years, if evolution has changed worms into humans in the same time frame? Professor Gould wrote, “the maintenance of stability within species must be considered as a major evolutionary problem.”7 See: How did blind chemistry create mind/ intelligence, meaning, altruism and morality? If everything evolved, and we invented God, as per evolutionary teaching, what purpose or meaning is there to human life? Should students be learning nihilism (life is meaningless) in science classes? See: Why is evolutionary ‘just-so’ story-telling tolerated? Evolutionists often use flexible story-telling to ‘explain’ observations contrary to evolutionary theory. NAS(USA) member Dr Philip Skell wrote, “Darwinian explanations for such things are often too supple: Natural selection makes humans self-centered and aggressive—except when it makes them altruistic and peaceable. Or natural selection produces virile men who eagerly spread their seed—except when it prefers men who are faithful protectors and providers. When an explanation is so supple that it can explain any behavior, it is difficult to test it experimentally, much less use it as a catalyst for scientific discovery.”8 See: Where are the scientific breakthroughs due to evolution? Dr Marc Kirschner, chair of the Department of Systems Biology, Harvard Medical School, stated: “In fact, over the last 100 years, almost all of biology has proceeded independent of evolution, except evolutionary biology itself. Molecular biology, biochemistry, physiology, have not taken evolution into account at all.”9 Dr Skell wrote, “It is our knowledge of how these organisms actually operate, not speculations about how they may have arisen millions of years ago, that is essential to doctors, veterinarians, farmers … .”10 Evolution actually hinders medical discovery.11 Then why do schools and universities teach evolution so dogmatically, stealing time from experimental biology that so benefits humankind? See: Science involves experimenting to figure out how things work; how they operate. Why is evolution, a theory about history, taught as if it is the same as this operational science? You cannot do experiments, or even observe what happened, in the past. Asked if evolution has been observed, Richard Dawkins said, “Evolution has been observed. It’s just that it hasn’t been observed while it’s happening.”12 See: Why is a fundamentally religious idea, a dogmatic belief system that fails to explain the evidence, taught in science classes? Karl Popper, famous philosopher of science, said “Darwinism is not a testable scientific theory, but a metaphysical [religious] research programme ….”13 Michael Ruse, evolutionist science philosopher admitted, “Evolution is a religion. This was true of evolution in the beginning, and it is true of evolution still today.”14 If “you can’t teach religion in science classes”, why is evolution taught? See:
Thinning- and fire-induced changes in forest structure and processes can influence wildlife on several levels. Specifically, hazard reduction treatments potentially influence songbirds and small mammals at the community, the population, and the individual level. ~ Nest success of songbirds: Ground nesters: dark-eyed junco (Junco hyemalis) ~ Composition and abundance of songbird species ~ Foraging patterns of bark gleaning birds (nuthatches and woodpeckers) ~ Composition and abundance of small mammal species Yellow-pine chipmunk, a common species on research sites. ~ Effects of hazard reduction treatments on songbird nest success ~Woodpecker use of beetle-infested trees The insects and disease discipline provides data on beetle infestation to identify trees for tracking woodpecker use. \|An example of a cavity nest. A red-breasted nuthatch nestling pokes its head out.\| ~37 songbird species have been recorded on research sites. ~Common songbird species identified include: dark eyed juncos (Junco hyemalis), chipping sparrows (Spizella passerine), red-breasted nuthatches (Sitta canadensis), mountain chickadees (Poecile gambeli), western tanagers (Piranga ludoviciana), Cassin's vireo (Vireo cassinii), yellow-rumped warblers (Dendroica coronata), and pine siskins (Carduelis pinus). ~9 small mammal species have been recorded on research sites. ~Common small mammal species identified include: deer mice (Peromyscus maniculatus), yellow pine chipmunks (Tamias amoenus), and red-backed voles (Clethrionomys gapperi). ~If you would like to see some examples of our wildlife, or the wildlife crew in action, check out our wildlife pictures. \|Lubrecht FFS Home\|
Saltmarshes are found in the upper coastal intertidal zone between land and salt water or brackish water in temperate and high latitudes where there isn’t strong wave action and sediments are able to build up. They are found on all continents other than Antarctica. They are dominated by dense stands of salt-tolerant (halophytic) plants such as herbs, grasses and low shrubs. These land plants are essential to the stability of the salt marsh because they trap and bind sediments. Saltmarshes play a large role in the aquatic food web and the exporting of nutrients to coastal waters. They also provide habitats for many terrestrial animals such as migrating birds as well as providing protection to the coastline. Unlike other land habitats saltmarshes are strongly influenced by the daily tidal flow that floods the area. This supplies sediments, nutrients and water to the marsh.
Folklore is a relatively new term (1846) used to describe a tradition practiced since the beginning of time. Oral tradition was a necessity in society before the use of written communication and, afterward, when very few people were educated in its use. Generations translated their customs, religious beliefs, traditions, behaviors, and more through storytelling. This not only ensured the continuity of these cultural precepts, but was used as a form of entertainment. Today, these tales from all over Europe have survived, and still thrive in the halls of education and in stories for children. Though the Medieval Period is often overlapping in its timeline with the Renaissance Period, many of today’s medieval legends came out of both of these eras, and some began before the Christian Era. Celtic Mythology grew from ancient lore, both Irish and Welsh, and was ordered into four cycles by Christian monks of the 12th century and later. These cycles, Mythological, Ulster, Fenian, and Kings “Historical,” each deal with their own subject matter and contain stories relevant to each. The Book of Invasions told of the supernatural visitors during the Mythological period, and included people, demons, and divine entities: Partholonians, Nemedians, Fomhóire, Fir Bholg, and Tuatha Dé Denann, and the Milesians. The Ulster Cycle grew from the ancient lore about heroes in the northern province of Ireland, such as the tale of Connor MacNessa, as told in the Sons of Usnach and Tain Bo Cuailgne. The Finian Cycle tales deal with Finn mac Cumhal, the leader of an Ireland-roaming warband under the reign of King Cormac mac Art. The stories include The Coming of Finn, The Quest of the Sons of Turenn, The Salmon of Knowledge, The Giant’s Causeway, and many others. While there are more than just legends and sagas from Ireland and Wales, the Welsh Mabinogian (fairy tales) resemble the stories in the Book of Invasions of Irish origin. The Legend of King Arthur and the Knights of the Round Table characters are also of Celtic nationality, and so there is some mention of them in that mythology. The Arthurian Legends are many, and some of the wars within the tales give credence to the thought that King Arthur may have actually existed around the 6th century A.D. Camelot was the geographical setting for King Arthur and his Knights of the Round Table, Gawaiin, Perceval, Lancelot, Galahad, and Tristan are as famous as the king himself. The Age of Chivalry they ushered in arrived after the Dark Ages and lent much romanticism to the stories. The French tales of Kid Charlemagne, known as the Song of Deeds, predated Arthurian legend, but have been incorporated into them in most literature as rival tales. This English poem of old describes events which occurred in Sweden and Denmark and is dated somewhere between the 8th and 11th centuries A.D. It describes a history of epic adventures and is believed to have been handed down through oral tradition. The only manuscript is currently in the British Museum and has survived the destruction of the monasteries under King Henry VIII and the fire that destroyed the personal library of Sir Robert Bruce Cotton (1571 – 1631 A.D.). This lengthy tale (over 1,300 lines long) depicts a Danish kingdom ravaged by a demon (Grendel) and a young Geatsman hero who comes and defeats the monster, unarmed, by ripping off its arm. Later, Grendel’s mother seeks revenge on the village and Beowulf must, once again, destroy the monster. He succeeds in his battle and rids the kingdom of its final threat. The hero returns to his own country and later becomes king of the Geats and reigns for 50 years before another villain, a dragon, rears its head in his native land and he slays it. However, he is slashed in the neck by it and dies shortly after. This ancient piece of literature remains a topic of study in modern education. The Tales of Mother Goose, Grimm’s Fairy Tales, Hans Christian Andersen, and many more, are stories that are mostly familiar to society today. A look into their history and other writers of children’s fantasy reminds us of the oral tradition once used by the ancients and continued through present day parents, as they recite the familiar stories of Little Red Riding Hood, The Three Little Pigs, Rumplestiltskin, and other childhood tales. Though most of these feel-good stories of moral value engage young children, a look at some of the original texts leaves parents questioning their telling as the story originated. The truth is that the original fairy tales were written for adults, and contained violence and unimaginable evils. Over the years, these stories have been altered to enable their telling to children, as they always had a moral truth in the underlying theme. Through their continued use in books, television, movies, and song, these stories of old have had their place in shaping moral thought in society. And as with all folktales, ancient lore, medieval legends, and fairy tales, they live on through the generations, in the art of oral tradition.
The protocol layer just above the Internet Layer is the Host-to-Host Transport Layer. This name is usually shortened to Transport Layer. The two most important protocols in the Transport Layer are Transmission Control Protocol ( TCP ) and User Datagram Protocol ( UDP ). TCP provides reliable data delivery service with end-to-end error detection and correction. UDP provides low-overhead, connectionless datagram delivery service. Both protocols deliver data between the Application Layer and the Internet Layer. Applications programmers can choose whichever service is more appropriate for their specific applications. The User Datagram Protocol gives application programs direct access to a datagram delivery service, like the delivery service that IP provides. This allows applications to exchange messages over the network with a minimum of protocol overhead. UDP is an unreliable, connectionless datagram protocol. (As noted before, "unreliable" merely means that there are no techniques in the protocol for verifying that the data reached the other end of the network correctly.) Within your computer, UDP will deliver data correctly. UDP uses 16-bit Source Port and Destination Port numbers in word 1 of the message header, to deliver data to the correct applications process. Figure 13.11 shows the UDP message format. Why do applications programmers choose UDP as a data transport service? There are a number of good reasons. If the amount of data being transmitted is small, the overhead of creating connections and ensuring reliable delivery may be greater than the work of retransmitting the entire data set. In this case, UDP is the most efficient choice for a Transport Layer protocol. Applications that fit a "query-response" model are also excellent candidates for using UDP . The response can be used as a positive acknowledgment to the query. If a response isn't received within a certain time period, the application just sends another query. Still other applications provide their own techniques for reliable data delivery, and don't require that service from the transport layer protocol. Imposing another layer of acknowledgment on any of these types of applications is inefficient. Applications that require the transport protocol to provide reliable data delivery use TCP because it verifies that data is delivered across the network accurately and in the proper sequence. TCP is a reliable , connection-oriented , byte-stream protocol. Let's look at each of the terms - reliable, connection-oriented, and byte-stream - in more detail. TCP provides reliability with a mechanism called Positive Acknowledgment with Re-transmission ( PAR ) . Simply stated, a system using PAR sends the data again, unless it hears from the remote system that the data arrived okay. The unit of data exchanged between cooperating TCP modules is called a segment (see Figure 13.12 ). Each segment contains a checksum that the recipient uses to verify that the data is undamaged. If the data segment is received undamaged, the receiver sends a positive acknowledgment back to the sender. If the data segment is damaged, the receiver discards it. After an appropriate time-out period, the sending TCP module retransmits any segment for which no positive acknowledgment has been received. TCP is connection-oriented. It establishes a logical end-to-end connection between the two communicating hosts. Control information, called a handshake , is exchanged between the two endpoints to establish a dialogue before data is transmitted. TCP indicates the control function of a segment by setting the appropriate bit in the Flags field in word 4 of the segment header . The type of handshake used by TCP is called a three-way handshake because three segments are exchanged. Figure 13.13 shows the simplest form of the three-way handshake. Host A begins the connection by sending host B a segment with the "Synchronize sequence numbers" ( SYN ) bit set. This segment tells host B what sequence number host A will use as a starting number for its segments. (Sequence numbers are used to keep data in the proper order.) Host B responds to A with a segment that has the "Acknowledgment" ( ACK ) and SYN bits set. B's segment acknowledges the receipt of A's segment, and informs A which Sequence Number host B will start with. Finally, host A sends a segment that acknowledges receipt of B's segment, and transfers the first actual data. In this figure, note that the first packet in each direction has the SYN bit set, and all subsequent packets have the ACK bit set. After this exchange, host A's TCP has positive evidence that the remote TCP is alive and ready to receive data. As soon as the connection is established, data can be transferred. When the cooperating modules have concluded the data transfers, they will exchange a three-way handshake with segments containing the "No more data from sender" bit (called the FIN bit ) to close the connection. It is the end-to-end exchange of data that provides the logical connection between the two systems. TCP views the data it sends as a continuous stream of bytes, not as independent packets. Therefore, TCP takes care to maintain the sequence in which bytes are sent and received. The "Sequence Number" and "Acknowledgment Number" fields in the TCP segment header keep track of the bytes. The TCP standard does not require that each system start numbering bytes with any specific number; each system chooses the number it will use as a starting point. To keep track of the data stream correctly, each end of the connection must know the other end's initial number. The two ends of the connection synchronize byte-numbering systems by exchanging SYN segments during the handshake. The "Sequence Number" field in the SYN segment contains the Initial Sequence Number ( ISN ), which is the starting point for the byte-numbering system. The ISN is chosen at random. Each byte of data is numbered sequentially from the ISN , so the first real byte of data sent has a sequence number of ISN +1. The Sequence Number in the header of a data segment identifies the sequential position in the data stream of the first data byte in the segment. For example, if the first byte in the data stream was sequence number 1 ( ISN =0) and 4,000 bytes of data have already been transferred, then the first byte of data in the current segment is byte 4001, and the Sequence Number would be 4001. The Acknowledgment Segment (ACK) performs two functions: positive acknowledgment and flow control . The acknowledgment tells the sender how much data has been received, and how much more the receiver can accept. The Acknowledgment Number is the sequence number of the last byte received at the remote end. The standard does not require an individual acknowledgment for every packet. The acknowledgment number is a positive acknowledgment of all bytes up through that number. For example, if the first byte sent was numbered 1 and 2,000 bytes have been successfully received, the Acknowledgment Number would be 2000. The Window field contains the number of bytes the remote end is able to accept. If the receiver is capable of accepting 6,000 more bytes, the Window would be 6000. The window indicates to the sender that it can continue sending segments as long as the total number of bytes that it sends is smaller than the window of bytes that the receiver can accept. The receiver controls the flow of bytes from the sender by changing the size of the window. A zero window tells the sender to cease transmission until it receives a non-zero window value. Figure 13.14 shows a TCP data stream that starts with an Initial Sequence Number of 0. The receiving system has received and acknowledged 2,000 bytes, so the current Acknowledgment Number is 2000. The receiver also has enough buffer space for another 6,000 bytes, so it has advertised a Window of 6000. The sender is currently sending a segment of 1,000 bytes starting with Sequence Number 4001. The sender has received no acknowledgment for the bytes from 2001 on, but continues sending data as long as it is within the window. If the sender fills the window and receives no acknowledgment of the data previously sent, it will, after an appropriate time-out, send the data again starting from the first unacknowledged byte. In Figure 13.14 , retransmission would start from byte 2001 if no further acknowledgments are received. This procedure ensures that data is reliably received at the far end of the network. TCP is also responsible for delivering data received from IP to the correct application. The application that the data is bound for is identified by a 16-bit number called the port number. The Source Port and Destination Port are contained in the first word of the segment header. Correctly passing data to and from the Application Layer is an important part of what the Transport Layer services do.
Toba catastrophe theory Illustration of what the eruption might have looked like from approximately 26 miles (42 km) above Pulau Simeulue. \|Date\|\|Between 69,000 and 77,000 years ago\| 2.6845°N 98.8756°ECoordinates: 2.6845°N 98.8756°E \|Impact\|\|Most recent supereruption; plunged Earth into a 6- to 10-year-long volcanic winter, causing a bottleneck in human evolution and significant changes to regional topography.\| \|Lake Toba is the resulting crater lake\| The Toba supereruption (Youngest Toba Tuff or simply YTT) was a supervolcanic eruption that is believed to have occurred sometime between 69,000 and 77,000 years ago at Lake Toba (Sumatra, Indonesia). It is recognized as one of the Earth‘s largest known eruptions. The related catastrophe hypothesis holds that this event plunged the planet into a 6-to-10-year volcanic winter and possibly an additional 1,000-year cooling episode. This change in temperature is hypothesized to have resulted in the world’s human population being reduced to 10,000 or even a mere 1,000 breeding pairs, creating a bottleneck in human evolution. The Toba event is the most closely studied supereruption. In 1993, science journalist Ann Gibbons first suggested a link between the eruption and a bottleneck in human evolution. Michael R. Rampino of New York University and Stephen Self of the University of Hawaii at Manoa quickly lent their support to the idea. The theory was further developed in 1998 by Stanley H. Ambrose of the University of Illinois at Urbana-Champaign. The Toba eruption or Toba event occurred at what is now Lake Toba about 73,000±4,000 years ago. The Toba eruption was the latest of the three major eruptions which occurred at Toba in the last 1 million years. The last eruption had an estimated Volcanic Explosivity Index of 8 (described as “mega-colossal”), or magnitude ≥ M8; it thus made a sizeable contribution to the 100 × 30 km2 caldera complex. Dense-rock equivalent estimates of eruptive volume for the eruption vary between 2,000 km3 and 3,000 km3, but the most frequently quoted DRE is 2,800 km3 (about 7×1015 kg) of erupted magma, of which 800 km3 was deposited as ash fall. It was two orders of magnitude greater in erupted mass than the largest volcanic eruption in historic times, in 1815 at Mount Tambora in Indonesia, which caused the 1816 “Year Without a Summer” in the northern hemisphere. Although the Toba eruption took place in Indonesia, it deposited an ash layer approximately 15 centimetres thick over the entirety of South Asia. A blanket of volcanic ash was also deposited over the Indian Ocean, and the Arabian and South China Sea. Deep-sea cores retrieved from the South China Sea extended the known distribution of the eruption and suggest that the 2,800 km3 calculation of the eruption magnitude is a minimum value or even an underestimate. Volcanic winter and cooling The apparent coincidence of the eruption with the onset of the last glacial period attracted the scientists’ interest. Michael L. Rampino and Stephen Self argued that the eruption caused a “brief, dramatic cooling or ‘volcanic winter'”, which resulted in a global mean surface temperature drop of 3–5 °C and accelerated the glacial transition from warm to cold temperatures of the last glacial cycle. Zielinski showed Greenland ice core evidence for a 1,000-year cool period with low δ18O and increased dust deposition immediately following the eruption. He further suggested that this 1,000-year cool period (stadial) could have been caused by the eruption, and that the longevity of the Toba stratospheric loading may account at least for the first two centuries of the cooling episode. Rampino and Self believe that global cooling was already underway at the time of the eruption, but the procedure was extremely slow; YTT “may have provided the extra ‘kick’ that caused the climate system to switch from warm to cold states.” Oppenheimer discounts the arguments that the eruption triggered the last glaciation, but he accepts that it may have been responsible for a millennium of cool climate prior to the Dansgaard-Oeschger event. According to Alan Robock, the Toba incident did not initiate an ice age. Using an emission of 6 billion tons of sulphur dioxide, his simulations demonstrated a maximum global cooling of around 15 °C, approximately three years after the eruption. As the saturated adiabatic lapse rate is 4.9 °C/1,000 m for temperatures above freezing, this means that the tree line and the snow line were around 3,000 m (9,900 ft) lower at this time. Nevertheless, the climate recovered over a few decades. Robock found no evidence that the 1,000-year cold period seen in Greenland ice core records was directly generated by the Toba eruption. Nevertheless, he argues that the volcanic winter would have been colder and longer-lasting than Ambrose assumed, which strengthens his argument for a genetic bottleneck. Contrary to Robock, Oppenheimer believes that estimates of a surface temperature drop of 3–5 °C after the eruption are probably too high; a figure closer to 1 °C appears more realistic. Robock criticized Oppenheimer’s analysis, arguing that it is based on simplistic T-forcing relationships. Despite the different approaches and estimates, scientists agree that a supereruption like the one at Lake Toba must have led to very extensive ash-fall layers and injection of noxious gases into the atmosphere, having severe worldwide effects on climate and weather. Additionally, the Greenland ice core data display an abrupt climate change around this time, but there is no consensus that the eruption directly generated the 1,000-year cold period seen in Greenland or triggered the last glaciation. Genetic bottleneck theory Ann Gibbons first suggested, in an article in the October 1993 edition of Science, that a bottleneck in human evolution about 50,000 years ago could be linked to the Toba eruption. Rampino and Self backed up this idea in a letter to the journal later that year. The bottleneck theory was then further developed by Ambrose in 1998 and Rampino & Ambrose in 2000, who invoked the Toba eruption to explain a severe culling of the human population. According to the supporters of the genetic bottleneck theory, between 50,000 and 100,000 years ago, human population suffered a severe population decrease—only 3,000 to 10,000 individuals survived—followed eventually by rapid population increase, innovation, progress and migration. Several geneticists, including Lynn Jorde and Henry Harpending, have proposed that the human race was reduced to approximately five to ten thousand people. Genetic evidence suggests that all humans alive today, despite apparent variety, are descended from a very small population, perhaps between 1,000 to 10,000 breeding pairs about 70,000 years ago. Note that this is an estimate of ancestors, not of total human population. Isolated human populations that eventually died out without descendants may have also existed in numbers that cannot be estimated by geneticists. Ambrose and Rampino proposed in the late 1990s that a genetic bottleneck could have been caused by the climate effects of the Toba eruption. The supporters of the Toba catastrophe theory suggest that the eruption resulted in a global ecological disaster with extreme phenomena, such as worldwide vegetation destruction, and severe drought in the tropical rainforest belt and in monsoonal regions. Τhis massive environmental change created population bottlenecks in species that existed at the time, including hominids; this in turn accelerated differentiation of the reduced human population. Therefore, Toba may have caused modern races to differentiate abruptly only 70,000 years ago, rather than gradually over one million years. Robock believes that, indeed, a 10-year volcanic winter triggered by YTT could have largely destroyed the food supplies of humans and therefore caused a significant reduction in population sizes. Gene analysis of some genes shows divergence anywhere from 60,000 to 2 million years ago. This does not contradict the Toba theory, however, because Toba is not conjectured to be an extreme bottleneck event. The complete picture of gene lineages, including present-day levels of human genetic variation, allows the theory of a Toba-induced human population bottleneck. However, research by archaeologist Michael Petraglia’s team cast doubt on Ambrose’s theory. Petraglia and his team found stone tools in southern India, above and below a thick layer of ash from the Toba eruption. The tools from each layer were remarkably similar, and Petraglia says that this shows that the huge dust clouds from the eruption did not wipe out the local population of people: A 2009 study by Martin A. J. Williams’s team challenges Petraglia’s findings. Williams analysed pollen from a marine core in the Bay of Bengal with stratified Toba ash, and argued that the eruption caused prolonged deforestation in South Asia. Ambrose, who is a co-author of the study, calls the evidence “unambiguous”, and further argues that YTT may have forced our ancestors to adopt new survival strategies, which permitted them to replace Neanderthals and “other archaic human species”. However, both Neanderthals in Europe and the small-brained Homo floresiensis in Southeastern Asia survived YTT by 50,000 and 60,000 years respectively. Oppenheimer accepts that the arguments proposed by Rampino and Ambrose are plausible, but they are not yet compelling for two reasons: it is difficult to estimate the global and regional climatic impacts of the eruption, and, at the same time, we cannot conclude with any confidence that the eruption actually preceded the bottleneck. Furthermore, a 2010 geneticists’ study seems to question the foundations of the Toba bottleneck theory: analysis of Alu sequences across the entire human genome has shown that the effective human population was already less than 26,000 as far back as 1.2 million years ago, suggesting that no Toba bottleneck was necessary. Possible explanations for the low population size of human ancestors may include repeated population bottlenecks or periodic replacement events from competing Homo subspecies. Genetic bottlenecks related to the human population Evolutionary biologist Richard Dawkins has postulated that human mitochondrial DNA (inherited only from one’s mother) and Y chromosome DNA (from one’s father) show coalescence at around 140,000 and 60,000 years ago respectively. In other words, all living humans’ female line ancestry trace back to a single female (Mitochondrial Eve) at around 140,000 years ago. Via the male line, all humans can trace their ancestry back to a single male (Y-chromosomal Adam) at 60,000 to 90,000 years ago. This is consistent with the Toba catastrophe theory which suggests that a bottleneck of the human population occurred c. 70,000 years ago, proposing that the human population was reduced to c. 15,000 individuals when the Toba supervolcano in Indonesia erupted and triggered a major environmental change, including a volcanic winter. The theory is based on geological evidences of sudden climate change at that time, and on coalescence evidences of some genes (including mitochondrial DNA, Y-chromosome and some nuclear genes) and the relatively low level of genetic variation among present-day humans. However, such coalescence is genetically expected and does not, in itself, indicate a population bottleneck, because mitochondrial DNA and Y-chromosome DNA are only a small part of the entire genome, and are atypical in that they are inherited exclusively through the mother or through the father, respectively. Most genes in the genome are inherited randomly from either father or mother, thus can be traced back in time via either matrilineal or patrilineal ancestry. Research on many (but not necessarily most) genes find various coalescence points from 2 million years ago to 60,000 years ago, according to the genes considered, thus disproving the existence of more recent extreme bottlenecks (i.e. a single breeding pair). On the other hand, in 2000, a Molecular Biology and Evolution paper suggested a transplanting model or a ‘long bottleneck’ to account for the limited genetic variation, rather than a catastrophic environmental change. This would be consistent with suggestions that in sub-Saharan Africa human populations could have dropped at times as low as 2,000, for perhaps as long as 100,000 years, before numbers began to expand again in the Late Stone Age One early oversight of many early studies is that the fixation of alleles (the object of coalescent theory study) is not a discrete mathematical function, but a probabilistic function, and it is highly dependent on the ploidy being studied. Takahata (1999) was the first molecular anthropologist to point out that conclusions drawn from single locus studies suffer from the large randomness of the fixation process. Schaffner (2004) has cleared up this issue by demonstrating the three sets of fixation ranges, haploid, X-linked and diploid where TMRCAs for different loci are expected to fall. Takahata (1993) estimated the effective human population size at 11,000 individuals, and Schaffner working on an improved set of X-linked markers from low recombination regions of the X-chromosome identified an effective size of approximately 12,000 individuals. PDHA1 falls on the edge of fixation times for X-linked chromosome. For autosomes, the MX1 locus and the HLA loci appear to preserve past diversity in the human population. With few exceptions, however, X-linked and autosomes appear to coalesce under a common population size. Just as mitochondria are inherited matrilineally, Y-chromosomes are inherited patrilineally. Y chromosomal TMRCA, the time of the Y-chromosomal Adam, lie in the 42 to 110ky range, which is a little less than half the TMRCA of mtDNA. Importantly, the genetic evidence suggests that the most recent patriarch of all humanity is much more recent than the most recent matriarch, suggesting that ‘Adam’ and ‘Eve’ were not alive at the same time. While ‘Eve’ is believed to have lived more than 140,000 years ago, ‘Adam’ appears to have lived less than 110,000 years ago. According to Wilder et al. (2004), the lower TMRCA of Y is due to an effective population size of males 1/2 that of females over most of human evolution. Even with a reduced effective population size there are problems with this explanation. Recently, with more mitogenomic sequences from Africa, evidence has grown for an early population size expansion. This expansion probably started prior to 100,000 years ago and greatly increasing after 100,000 years ago. The effective size of the human population should have well exceeded 104 individuals between 80,000 to 120,000 years ago. Given this expansion, implicit male populations sizes would have improbably coalesced to Y-Adam within that time frame. However, the greatest age for Y TMRCA is more recent than the evidence for expansion. In addition, despite evidence of a bottleneck, the human mtDNA TMRCA range remains consistent with population sizes estimates from X-linked and autosomal loci. However, Y-chromosomes TMRCA is not consistent with mtDNA or either of these sets (see figure:TMRCAs of loci). This inconsistency may be explained by some form of Y chromosome selection (cultural, or genetic). A Y-chromosomal lineage might have swept the male population. However, if true the place of greatest Y chromosomal diversity could be anywhere that humans inhabited Africa. However, Y diversity is greatest in Southern Africa, close to the earliest female population split predicted by Behar et al. (2009) suggesting the earliest branch in Y should be between 125,000 and 150,000 Ka in age. This suggests a SNP rate inaccuracy in the Y-chromosomal and/or mtDNA molecular clock. A recent study of X-chromosome suggests that different rates of male sperm production between humans and chimps has altered the molecular clock in sex chromosomes. This shift in the molecular clock would not affect the mtDNA SNP rate and would affect the Y-chromosomal rate more than X-linked and autosomes, since these Y-chromosomal lineages spend the most time in male testes. The term bottleneck has been used to describe the population structure that created mtDNA Eve. The appearance of a bottleneck was a consequence of the appearance of a ‘big bang’ of HVR branching about the time humans first left Africa. From that point back to the TMRCA was less than 100,000 years and the population size estimate was below 5000 effective females. Looking backwards in time this is what might be called a retrograde bottleneck, however it is an artifact of coalescence process, since the coalescence of mitogenomes on the sequence of the MRCA (the event which initiated with mtDNA Eve and extended to the extant population) conceals the population size from all points earlier than that mutation (see figure Retrograde look at bottlenecks). Therefore the population size could have been of equal size going back 100,000s of years, to the time in which Neanderthals’ ancestors and Modern humans’ ancestors were part of a single population. Evidence against a population bottleneck The work done on Neanderthal sequencing (Green 2007) has identified little evidence of Neanderthal contribution to humans, moreover it describes an effective size of the population when humans and Neanderthals split was about 3000 individuals. Taken in the light of Schaffner’s and Takahata’s effective populations sizes, 3000 < Ne, female < 6000 and 2000 < Ne, male < 4000 does not appear to represent a magnitude shift downward from the average size. Taking a null hypothesis, prior to and after the mtDNA MRCA population sizes appear to reflect long-term small population structure up until 70,000~150,000 years ago, not a brief constricting bottleneck, but a long period of constrained size followed by an expansion. Evidence for a population bottleneck Confidence intervals of population size do not require an alternative, population bottleneck, hypothesis. However, a bottleneck may have existed. If the population size were at 12,000 individuals as suggested by X-chromosomal studies, the Ne for mtDNA and Y in particular, is below the expected median TMRCAs (See image Above and on the left). Y chromosome and mtDNA may be more representative of population structure immediately prior to expansion. However, meshing mtDNA TMRCA and Y TMRCA is problematic. If these two loci could be treated together, they would likely fall significantly below the X-linked and autosome-derived size estimates for any given TCHLCA. Atkinson, Gray & Drummond (2009) show that prior to 150,000 years ago the population could have been as low as 1000 effective females (~1500 total, 4500 census) and as high as 11,000 effective females with a lower population size between 150,000 to 200,000 years ago. Whereas X-chromosome and autosomes warrant larger population size minima, thousands of females, these loci of larger ploidy are capable of sensing population structure of much longer periods. Such periods may include recent and ancient population structures and size oscillations. Most population structure models for Africa have assumed much of the growth occurred very recently, however Atkinson et al. (2009) shows that by 100,000 years ago the minimum female population size exceed the estimated population size for females. The flat population/recent growth model is troubled in considering an ancient population core in Tanzania (Gonder. et al. (2007) early East African/Khoisan split (Behar et al. 2008), and spread of L2 in parts of Africa where L0 and L1 are found in low abundance. Simply, the evidence of lineage growth appears to correlate with growth in geographic regions in which humans live. Retrospectively, this suggests that population size was growing as new lineages appears to expand territory. Comparing these observations with populations sizes suggested by X-chromosome (~7000 females) one might expect a low stand of the human population size of 1/3 to 1/2 this size between 150,000 to 250,000 years ago. This indicates that earlier periods had a reciprocal, or larger size (>7000 females) between 200,000 and 500,000 years ago. Other authors such as Endicott et al. (2009) think that bottlenecks in the human prehistory were such a common feature that they interfere with TMRCA determinations and imply the possible effect of the OIS-6 on population size reduction with a TMRCA around the time of late pliestocene climate optimum, approximately 120,000 years ago. Human parasite: analysis of louse genes Alan Rogers, a co-author of this study and professor of anthropology at the University of Utah, says: “The record of our past is written in our parasites.” Rogers and others have proposed the bottleneck may have occurred because of a mass die-off of early humans due to a globally catastrophic volcanic eruption. The analysis of louse genes confirmed that the population of Homo sapiens mushroomed after a small band of early humans left Africa sometime between 150,000 and 50,000 years ago. Human pathogen: analysis of Helicobacter pylori genes Recent research states that genetic diversity in the pathogenic bacterium Helicobacter pylori decreases with geographic distance from East Africa, the birthplace of modern humans. Using the genetic diversity data, the researchers have created simulations that indicate the bacteria seem to have spread from East Africa around 58,000 years ago. Their results indicate modern humans were already infected by H. pylori before their migrations out of Africa, and H. pylori remained associated with human hosts since that time. Genetic bottlenecks of other mammals The eruption may have also caused bottlenecks or extinctions in some animals (especially those in Southeast Asia, India, far north as China and as far west as Europe and Africa). The populations of the Eastern African chimpanzee, Bornean orangutan, central Indian macaque, the cheetah, the tiger, and the separation of the nuclear gene pools of eastern and western lowland gorillas, all recovered from very low numbers around 70,000–55,000 years ago. Migration after Toba It is currently not known where human populations were living at the time of the eruption. The most plausible scenario is that all the survivors were populations living in Africa, whose descendants would go on to populate the world. However, recent archeological finds, mentioned above, have suggested that a human population may have survived in Jwalapuram, Southern India. Recent analyses of mitochondrial DNA have set the estimate for the major migration from Africa from 60,000–70,000 years ago, around 10–20,000 years earlier than previously thought, and in line with dating of the Toba eruption to around 66,000–76,000 years ago. During the subsequent tens of thousands of years, the descendants of these migrants populated Australia, East Asia, Europe, and the Americas.
When you shift gears in your manual-transmission car, you move a rod that moves a fork that engages the gear. Depending which gear you're shifting to, a different fork does the job. The fork moves the collar to the desired gear, and dog teeth on the collar mesh up with holes on the gear in order to engage it. You engage reverse gear through a separate, small idler gear. The reverse gear always turns in the opposite direction of the other (forward) gears. In years past, double-clutching was common in order to disengage a gear, allow the collar and next gear to reach the same speed, and then to engage the new gear. To double-clutch shift, you pushed the clutch pedal to free the engine from the transmission. Then the collar moved into neutral. You released the clutch and revved the engine to get it to the right rpm value for the next gear so the collar and the next gear spun at the same rate to allow the dog teeth to engage the gear. When the engine hit the right speed, you depressed the clutch again in order to lock the collar into place on the next gear. Modern cars use synchronizers in order to avoid the need for double-clutching. A synchronizer, or "synchro," lets the collar and gear synchronize their speeds while they're already in contact but before the dog teeth engage. Each manufacturer's synchro is slightly different than the others, but the basic idea is the same. For instance, a cone on one gear will fit into a cone-shaped depression on the collar. The gear and collar synchronize their speeds thanks to the friction between the cone and collar. Then the outer part of the collar moves out of the way so that the gear can be engaged by the dog teeth.
Like what you saw? Create FREE Account and: Function Notation with Logs and Exponentials - Problem 1 Solving a logarithmic equation in a function notation. So whenever we see something in function notation what we have to do is just plug in the number in the parenthesis. With log there’s no difference. So behind me I have a fairly elaborate log equation and we are asked to find g of 2. Basically what we want to do is plug 2 in wherever we see x. There’s only one x in this equation so we plug in 2 there, 5 times 2 minus 1² plus 1. So now using order of operations, we know we need to simplify our parenthesis first. 5 times 2 is 10 minus 9 is sorry minus 1 is 9, getting a little bit ahead of myself, so what we have right here is log base 3 of 9² to 3 and the plus 1. So hopefully you are getting into a point where you can start to recognize what these log things actually do. And this is basically saying 3 to what power is equal to 9? 3² is equal to 9 so this term right here is just 2. From here we know that 3 times 2² plus 1, we just have a simple equation solve it out. 2² is 4, 3 times 2² 12 plus 1, 13. So just by using our function notation and our properties of logs, we were able to solve this out.
By the time severe weather hits, it's already too late. Disaster preparedness is about having an established safety plan. Whether it's preparedness for floods, earthquakes, hurricanes, or fires, the key to survival in disasters is planning. Use our preparedness section to stay informed, make a plan, and most importantly—remain safe in an emergency. Prepare For an Earthquake In the event of an earthquake: Learn What to Do During an Earthquake. Hold periodic family drills to practice what you have learned. Through practice, you can condition yourselves to react spontaneously and safely when the first jolt or shaking is felt. In each room of your home, identify the safest places to "drop, cover, and hold on" during an earthquake. Practice going to these safe spots during family drills to ensure that everyone learns where they are. Survive on Your Own Assemble and maintain a household emergency supply kit, and be sure that all family members know where it is stored. The kit should consist of one or two portable containers (e.g., plastic tubs, backpacks, duffel bags) holding the supplies that your family would need to survive without outside assistance for at least 3 days following an earthquake or other disaster. Make additional, smaller kits to keep in your car(s) and at your place(s) of work. Stay in Contact List addresses, telephone numbers, and evacuation sites for all places frequented by family members (e.g., home, workplaces, schools). Include the phone number of an out-of-state contact. Ensure that family members carry a copy of this list, and include copies in your emergency supply kits. Care for People, Pets, and Property Get training in first aid and cardiopulmonary resuscitation (CPR) through your local chapter of the American Red Cross. Find out where you could shelter your pet should it become necessary to evacuate your home. Ensure that family members know how and when to call 9-1-1, how to use your home fire extinguisher, and how, where, and when to shut off your home's utilities (water, natural gas, and electricity). Ask your state insurance commissioner about the availability of earthquake insurance in your state. Earthquake Preparedness Checklist - Build a disaster supply kit and make a family plan - Fasten shelves securely to walls - Place large or heavy objects on lower shelves - Store breakable items such as bottled foods, glass, and china in low, closed cabinets with latches - Fasten heavy items such as pictures and mirrors securely to walls and away from beds, couches and anywhere people sit - Brace overhead light fixtures and top heavy objects - Know what natural gas smells like, so you can avoid leaks should an earthquake occur - Repair defective electrical wiring and leaky gas connections. These are potential fire risks. Get appropriate professional help. Do not work with gas or electrical lines yourself - Install flexible pipe fittings to avoid gas or water leaks. Flexible fittings are more resistant to breakage - Secure your water heater, refrigerator, furnace and gas appliances by strapping them to the wall studs and bolting to the floor. If recommended by your gas company, have an automatic gas shut-off valve installed that is triggered by strong vibrations - Repair any deep cracks in ceilings or foundations. Get expert advice if there are signs of structural defects - Be sure the residence is firmly anchored to its foundation - Store weed killers, pesticides, and flammable products securely in closed cabinets with latches and on bottom shelves - Locate safe spots in each room under a sturdy table or against an inside wall. Reinforce this information by moving to these places during each drill - Hold earthquake drills with your family members: Drop, cover and hold on During An Earthquake If you are... - DROP to the ground; take COVER by getting under a sturdy table or other piece of furniture; and HOLD ON until the shaking stops. If there isn't a table or desk near you, cover your face and head with your arms and crouch in an inside corner of the building. - Stay away from glass, windows, outside doors and walls, and anything that could fall, such as lighting fixtures or furniture. - Stay in bed if you are there when the earthquake strikes. Hold on and protect your head with a pillow, unless you are under a heavy light fixture that could fall. In that case, move to the nearest safe place. - Do not use a doorway except if you know it is a strongly supported, load-bearing doorway and it is close to you. Many inside doorways are lightly constructed and do not offer protection. - Stay inside until the shaking stops and it is safe to go outside. Do not exit a building during the shaking. Research has shown that most injuries occur when people inside buildings attempt to move to a different location inside the building or try to leave. - DO NOT use the elevators. - Be aware that the electricity may go out or the sprinkler systems or fire alarms may turn on. - Stay there. - Move away from buildings, streetlights, and utility wires. - Once in the open, stay there until the shaking stops. The greatest danger exists directly outside buildings, at exits and alongside exterior walls. Many of the 120 fatalities from the 1933 Long Beach earthquake occurred when people ran outside of buildings only to be killed by falling debris from collapsing walls. Ground movement during an earthquake is seldom the direct cause of death or injury. Most earthquake-related casualties result from collapsing walls, flying glass, and falling objects. In a moving car - Stop as quickly as safety permits and stay in the vehicle. Avoid stopping near or under buildings, trees, overpasses, and utility wires. - Proceed cautiously once the earthquake has stopped. Avoid roads, bridges, or ramps that might have been damaged by the earthquake. Trapped under debris - Do not light a match. - Do not move about or kick up dust. - Cover your mouth with a handkerchief or clothing. - Tap on a pipe or wall so rescuers can locate you. Use a whistle if one is available. Shout only as a last resort. Shouting can cause you to inhale dangerous amounts of dust. After An Earthquake After the earthquake is over, you should expect aftershocks. If you are indoors, make sure it is save before you head outside. Attempt to extinguish small fires, and check on your utilities: turn off the gas at the main, and be aware of gas leaks. Help injured or trapped persons. Remember to help your neighbors who may require special assistance such as infants, the elderly, and people with access and functional needs. Give first aid where appropriate. Do not move seriously injured persons unless they are in immediate danger of further injury. Call for help, but know that phone lines could be unavailable. In these cases, text your messages to your loved ones. It's also advised to keep the FEMA text number saved for shelter locations. Text SHELTER + your ZIP code to 43362 (4FEMA) to find the nearest shelter in your area (example: shelter 12345). Prepare For the Extreme Get Severe Weather Alerts - Tornado Preparedness - Tornado FAQ - Where Tornadoes Occur - Understand the Fujita Scale - Severe Storms and Supercells - Flash Floods - Radar FAQ - Severe Storms Lingo Hurricanes and Typhoons - Hurricane and Typhoon Preparedness - Storm Surge Basics - Storm Surge Survival Myths - Storm Surge: Know Your Elevation - Inland Flooding and Flash Flooding - Radar FAQ - Hurricane Lingo
\|Researchers are using the fruit fly to discover how the brain integrates multiple signals to identify one unique smell. It's work that has broader implication for how flies -- and ultimately, people -- learn.\| Think of the smell of an orange, a lemon, and a grapefruit. Each has strong acidic notes mixed with sweetness. And yet each fresh, bright scent is distinguishable from its relatives. These fruits smell similar because they share many chemical compounds. How, then does the brain tell them apart? How does the brain remember a complex and often overlapping chemical signature as a particular scent? Researchers at Cold Spring Harbor Laboratory (CSHL) are using the fruit fly to discover how the brain integrates multiple signals to identify one unique smell. It's work that has broader implication for how flies – and ultimately, people – learn. In work published in Nature Neuroscience, a team led by Associate Professor Glenn Turner describes how a group of neurons in the fruit fly brain recognize multiple individual chemicals in combination in order to define, or remember, a single scent. Kenyon cells have multiple, extremely long protrusions that grasp the projection neurons with a claw-like structure. Each Kenyon cell claw is wrapped tightly around only one projection neuron, meaning that it receives a signal from just one type of input. In addition to their unique structure, Kenyon cells are also remarkable for their selectivity. Because they're selective, they aren't often activated. Yet little is known about what in fact makes them decide to fire a signal. Turner and colleague Eyal Gruntman, who is lead author on their new paper, used cutting-edge microscopy to explore the chemical response profile for multiple claws on one Kenyon cell. They found that each claw, even on a single Kenyon cell, responded to different chemicals. Additional experiments using light to stimulate individual neurons (a technique called optogenetics) revealed that single Kenyon cells were only activated when several of their claws were simultaneously stimulated, explaining why they so rarely fire. Taken together, this work explains how individual Kenyon cells can integrate multiple signals in the brain to "remember" the particular chemical mixture as a single, distinct odor . Turner will next try to determine "what controls which claws are connected," which will provide insight into how the brain learns to assign a specific mix of chemicals as defining a particular scent. But beyond simple odor detection, the research has more general implications for learning. For Turner, the question driving his work forward is: what in the brain changes when you learn something? SOURCE Cold Springs Harbor Laboratory \|By 33rd Square\|\|Subscribe to 33rd Square\|
Choose any three by three square of dates on a calendar page. Circle any number on the top row, put a line through the other numbers that are in the same row and column as your circled number. Repeat this for a number of your choice from the second row. You should now have just one number left on the bottom row, circle it. Find the total for the three numbers circled. Compare this total with the number in the centre of the square. What do you find? Can you explain why this happens? Take any two digit number, for example 58. What do you have to do to reverse the order of the digits? Can you find a rule for reversing the order of digits for any two digit number? Can you explain how this card trick works? When the pack has been shuffled and then split, let us assume that there are x cards face up in the pile of 20. This being the case, there must be 20 - x cards face up in the second pile. When the pile of 20 is turned upside down there will be 20 - (20 - x) = x cards face up in the pile. Therefore both piles of cards will have the same number of cards ( x ) face up. Of course the trick works just as well if the volunteer chooses 25 cards or any other number of cards. You might like to convince yourself that this is so by rewriting the above solution replacing 20 by 25.
Electrical signals in the heart trigger heartbeats (see heart electrical system). These signals start at the top of the heart in an area called the right atrium. The electrical signals travel from the top of the heart to the bottom. They cause the heart muscle to contract as they travel through the heart. As the heart contracts, it pumps blood out to the rest of the body. An EKG shows how fast the heart is beating. It shows the heart's rhythm (steady or irregular) and where in the body the heartbeat is being recorded. It also records the strength and timing of the electrical signals as they pass through each part of the heart. An EKG is sometimes called a 12-lead EKG (or 12-lead ECG) because the electrical activity of the heart is most often recorded from 12 different places on the body at the same time. What an EKG revealsMany heart problems change the electrical signature of the heart in distinct ways. EKG recordings of this electrical activity can help reveal a number of heart problems, including: Why is an electrocardiogram done?An electrocardiogram (EKG) is done to evaluate signs and symptoms that could indicate heart problems. Some of the signs and symptoms that might be evaluated with an EKG include: Doctors also use EKGs to check how well heart treatments, such as drugs or medical devices, are working. What happens during an electrocardiogram?An electrocardiogram (EKG) is painless and harmless. A technician first attaches 12 soft patches called electrodes to the skin of the chest, arms, and legs. These electrodes are about the size of a quarter. To help an electrode stick to the skin, the technician may have to shave a patch of hair where the electrode will be attached. After the electrodes are placed on the skin, the patient lies still on a table for a few minutes while the electrodes detect the electrical signals of the heart. A machine then records these signals on graph paper or displays them on a screen. The entire test takes about 10 minutes. After the test, the electrodes are removed from the skin and discarded. Special EKGsThe common EKG described above, called a resting 12-lead EKG, records only a few minutes of heart signals at a time. It will show a heart problem only if the problem is present during the few minutes that the test is being run. Many heart problems are present all the time and will be found by a resting 12-lead EKG. But some heart problems, like those related to irregular heartbeat, can come and go. They may be present for only a few minutes out of the day or only while exercising. Special types of EKGs are used to help diagnose those kinds of problems. Three of these special EKGs are: Stress testSome heart problems are easier to diagnose when your heart is working harder and beating faster than when it's at rest. During stress testing, you exercise (or are given medicine if you are unable to exercise) to make your heart work harder and beat faster while heart tests are performed. During exercise stress testing, your blood pressure and EKG readings are monitored while you walk or run on a treadmill or pedal a bicycle. Other heart tests, such as nuclear heart scanning or echocardiography, also can be done at the same time. These would be ordered if your doctor needs more information than the exercise stress test can provide about how well your heart is working. If you are unable to exercise, a medicine can be injected through an intravenous line (IV) into your bloodstream to make your heart work harder and beat faster, as if you are exercising on a treadmill or bicycle. Nuclear heart scanning or echocardiography is then usually done. During nuclear heart scanning, radioactive tracer is injected into your bloodstream, and a special camera shows the flow of blood through your heart and arteries. Echocardiography uses sound waves to show blood flow through the chambers and valves of your heart and to show the strength of your heart muscle. Your doctor also may order two newer tests along with stress testing if more information is needed about how well your heart works. These new tests are magnetic resonance imaging (MRI) and positron emission tomography (PET) scanning of the heart. MRI shows detailed images of the structures and beating of your heart, which may help your doctor better assess if parts of your heart are weak or damaged. PET scanning shows the level of chemical activity in different areas of your heart. This can help your doctor determine if enough blood is flowing to the areas of your heart. A PET scan can show decreased blood flow caused by disease or damaged muscles that may not be detected by other scanning methods. Related categories• HEART TOPICS • HEALTH AND DISEASE • MEDICAL TESTS Source: National Heart, Lung and Blood Institute Home • About • Copyright © The Worlds of David Darling • Encyclopedia of Alternative Energy • Contact
Current ice melt rate in Pine Island Glacier may go on for decades A study of the Pine Island Glacier could provide insight into the patterns and duration of glacial melt. The Pine Island Glacier, a major outlet of the West Antarctic Ice Sheet, has been undergoing rapid melting and retreating for the past two decades. But new research by an international team including researchers from Lawrence Livermore National Laboratory shows that this same glacier also experienced rapid thinning about 8,000 years ago. Using LLNL’s Center for Accelerator Mass Spectrometry to measure beryllium-10 produced by cosmic rays in glacially transported rocks, Lawrence Livermore researchers Bob Finkel and Dylan Rood reported that the melting 8,000 years ago was sustained for decades to centuries at an average rate of more than 100 centimeters per year. This is comparable to modern-day melting rates. The findings indicate that modern-day melting and thinning could last for several more decades or even centuries. The research appears in the Feb. 20 issue of Science Express. “Pine Island Glacier has experienced rapid thinning at least once in the past. Once set in motion, rapid ice sheet changes in this region can persist for centuries,” said Finkel, one of the authors of the new findings. Ice mass loss from the Pine Island-Thwaites sector dramatically contributes to the sea level of the West Antarctic Ice Sheet. The Pine Island Glacier is currently experiencing significant acceleration, thinning and retreat. The rate of thinning from 2002-2007 on the grounding line (the part where the glaciers export the ice down the continent and lose contact to the ground and become a floating ice shelf) was between 1.2 meters per year and 6 meters per year. The change is likely tied to the increased influx of warm water to the cavity under the ice shelf at the glacial front. Dramatic changes over longer timescales — from centuries to millennia — are somewhat limited, so there is considerable uncertainty associated with model projections of the future evolution of timing and ice loss of the Pine Island Glacier. Current geological research is tied to the grounding line retreat across the continental shelf. However, little is known about the terrestrial thinning history and how the ice stream evolved from 8,000 years ago to the onset of present-day thinning. The team found that there was a direct correlation from glacial-geological samples consisting of cobblestones and granite boulders from the Hudson Mountains to rapid thinning in the Pine Island Glacier system about 8,000 years ago. “The melting of the Pine Island Glacier at a rate comparable to that over the past two decades is rare but not unprecedented,” Rood said. “Ongoing ocean-driven melting of the glacial ice shelf in current times may result in continued rapid thinning and ground line retreat for several more decades or even centuries.” Other institutions involved in the research include: The British Antarctic Survey; Durham University; University of California, Berkeley; University of California, Santa Barbara; Alfred Wegener Institute Helmholtz-Centre for Polar and Marine Research; Berkeley Geochronology Center; Lamont-Doherty Earth Observatory; and Columbia University.
\|\|This article includes a list of references, but its sources remain unclear because it has insufficient inline citations. (April 2014)\| A lathe // is a machine tool which rotates the workpiece on its axis to perform various operations such as cutting, sanding, knurling, drilling, or deformation, facing, turning, with tools that are applied to the workpiece to create an object which has symmetry about an axis of rotation. Lathes are used in woodturning, metalworking, metal spinning, thermal spraying, parts reclamation, and glass-working. Lathes can be used to shape pottery, the best-known design being the potter's wheel. Most suitably equipped metalworking lathes can also be used to produce most solids of revolution, plane surfaces and screw threads or helices. Ornamental lathes can produce three-dimensional solids of incredible complexity. The workpiece is usually held in place by either one or two centers, at least one of which can typically be moved horizontally to accommodate varying workpiece lengths. Other work-holding methods include clamping the work about the axis of rotation using a chuck or collet, or to a faceplate, using clamps or dogs. Examples of objects that can be produced on a lathe include candlestick holders, gun barrels, cue sticks, table legs, bowls, baseball bats, musical instruments (especially woodwind instruments), crankshafts, and camshafts. - 1 History - 2 Description - 3 Major categories - 4 Gallery - 5 Performance Evaluation - 6 See also - 7 References - 8 Further reading - 9 External links The lathe is an ancient tool, dating at least to ancient Egypt and known to be used in Assyria and ancient Greece. The lathe was very important to the Industrial Revolution. The origin of turning dates to around 1300 BCE when the Ancient Egyptians first developed a two-person lathe. One person would turn the wood work piece with a rope while the other used a sharp tool to cut shapes in the wood. Ancient Rome improved the Egyptian design with the addition of a turning bow. In the Middle Ages a pedal replaced hand-operated turning, freeing both the craftsman's hands to hold the woodturning tools. The pedal was usually connected to a pole, often a straight-grained sapling. The system today is called the "spring pole" lathe. Spring pole lathes were in common use into the early 20th century. An important early lathe in the UK was the horizontal boring machine that was installed in 1772 in the Royal Arsenal in Woolwich. It was horse-powered and allowed for the production of much more accurate and stronger cannon used with success in the American Revolutionary War in the late 18th century. One of the key characteristics of this machine was that the workpiece was turning as opposed to the tool, making it technically a lathe (see attached drawing). Henry Maudslay who later developed many improvements to the lathe worked at the Royal Arsenal from 1783 being exposed to this machine in the Verbruggen workshop. During the Industrial Revolution, mechanized power generated by water wheels or steam engines was transmitted to the lathe via line shafting, allowing faster and easier work. Metalworking lathes evolved into heavier machines with thicker, more rigid parts. Between the late 19th and mid-20th centuries, individual electric motors at each lathe replaced line shafting as the power source. Beginning in the 1950s, servomechanisms were applied to the control of lathes and other machine tools via numerical control, which often was coupled with computers to yield computerized numerical control (CNC). Today manually controlled and CNC lathes coexist in the manufacturing industries. A lathe may or may not have legs which sit on the floor and elevate the lathe bed to a working height. A lathe may be small and sit on a workbench or table, and not require a stand. Almost all lathes have a bed, which is (almost always) a horizontal beam (although CNC lathes commonly have an inclined or vertical beam for a bed to ensure that swarf, or chips, falls free of the bed). Woodturning lathes specialized for turning large bowls often have no bed or tail stock, merely a free-standing headstock and a cantilevered tool rest. At one end of the bed (almost always the left, as the operator faces the lathe) is a headstock. The headstock contains high-precision spinning bearings. Rotating within the bearings is a horizontal axle, with an axis parallel to the bed, called the spindle. Spindles are often hollow, and have exterior threads and/or an interior Morse taper on the "inboard" (i.e., facing to the right / towards the bed) by which work-holding accessories may be mounted to the spindle. Spindles may also have exterior threads and/or an interior taper at their "outboard" (i.e., facing away from the bed) end, and/or may have a hand-wheel or other accessory mechanism on their outboard end. Spindles are powered, and impart motion to the workpiece. The spindle is driven either by foot power from a treadle and flywheel or by a belt or gear drive to a power source. In most modern lathes this power source is an integral electric motor, often either in the headstock, to the left of the headstock, or beneath the headstock, concealed in the stand. In addition to the spindle and its bearings, the headstock often contains parts to convert the motor speed into various spindle speeds. Various types of speed-changing mechanism achieve this, from a cone pulley or step pulley, to a cone pulley with back gear (which is essentially a low range, similar in net effect to the two-speed rear of a truck), to an entire gear train similar to that of a manual-shift auto transmission. Some motors have electronic rheostat-type speed controls, which obviates cone pulleys or gears. The counterpoint to the headstock is the tailstock, sometimes referred to as the loose head, as it can be positioned at any convenient point on the bed by sliding it to the required area. The tail-stock contains a barrel which does not rotate, but can slide in and out parallel to the axis of the bed, and directly in line with the headstock spindle. The barrel is hollow, and usually contains a taper to facilitate the gripping of various type of tooling. Its most common uses are to hold a hardened steel center, which is used to support long thin shafts while turning, or to hold drill bits for drilling axial holes in the work piece. Many other uses are possible. Metalworking lathes have a carriage (comprising a saddle and apron) topped with a cross-slide, which is a flat piece that sits crosswise on the bed, and can be cranked at right angles to the bed. Sitting atop the cross slide is usually another slide called a compound rest, which provides 2 additional axes of motion, rotary and linear. Atop that sits a toolpost, which holds a cutting tool which removes material from the workpiece. There may or may not be a leadscrew, which moves the cross-slide along the bed. Woodturning and metal spinning lathes do not have cross-slides, but rather have banjos, which are flat pieces that sit crosswise on the bed. The position of a banjo can be adjusted by hand; no gearing is involved. Ascending vertically from the banjo is a tool-post, at the top of which is a horizontal toolrest. In woodturning, hand tools are braced against the tool rest and levered into the workpiece. In metal spinning, the further pin ascends vertically from the tool rest, and serves as a fulcrum against which tools may be levered into the workpiece. Unless a workpiece has a taper machined onto it which perfectly matches the internal taper in the spindle, or has threads which perfectly match the external threads on the spindle (two conditions which rarely exist), an accessory must be used to mount a workpiece to the spindle. A workpiece may be mounted on a mandrel, or circular work clamped in a three- or four-jaw chuck. For irregular shaped workpieces it is usual to use a four jaw (independent moving jaws) chuck. These holding devices mount directly to the Lathe headstock spindle. In precision work, and in some classes of repetition work, cylindrical workpieces are usually held in a collet inserted into the spindle and secured either by a draw-bar, or by a collet closing cap on the spindle. Suitable collets may also be used to mount square or hexagonal workpieces. In precision toolmaking work such collets are usually of the draw-in variety, where, as the collet is tightened, the workpiece moves slightly back into the headstock, whereas for most repetition work the dead length variety is preferred, as this ensures that the position of the workpiece does not move as the collet is tightened. A soft workpiece (e.g., wood) may be pinched between centers by using a spur drive at the headstock, which bites into the wood and imparts torque to it. A soft dead center is used in the headstock spindle as the work rotates with the centre. Because the centre is soft it can be trued in place before use. The included angle is 60°. Traditionally, a hard dead center is used together with suitable lubricant in the tailstock to support the workpiece. In modern practice the dead center is frequently replaced by a live center, as it turns freely with the workpiece — usually on ball bearings — reducing the frictional heat, especially important at high speeds. When clear facing a long length of material it must be supported at both ends. This can be achieved by the use of a traveling or fixed steady. If a steady is not available, the end face being worked on may be supported by a dead (stationary) half center. A half center has a flat surface machined across a broad section of half of its diameter at the pointed end. A small section of the tip of the dead center is retained to ensure concentricity. Lubrication must be applied at this point of contact and tail stock pressure reduced. A lathe carrier or lathe dog may also be employed when turning between two centers. In woodturning, one variation of a live center is a cup center, which is a cone of metal surrounded by an annular ring of metal that decreases the chances of the workpiece splitting. A circular metal plate with even spaced holes around the periphery, mounted to the spindle, is called an "index plate". It can be used to rotate the spindle to a precise angle, then lock it in place, facilitating repeated auxiliary operations done to the workpiece. Other accessories, including items such as taper turning attachments, knurling tools, vertical slides, fixed and traveling steadies, etc., increase the versatility of a lathe and the range of work it may perform. Modes of use When a workpiece is fixed between the headstock and the tail-stock, it is said to be "between centers". When a workpiece is supported at both ends, it is more stable, and more force may be applied to the workpiece, via tools, at a right angle to the axis of rotation, without fear that the workpiece may break loose. When a workpiece is fixed only to the spindle at the headstock end, the work is said to be "face work". When a workpiece is supported in this manner, less force may be applied to the workpiece, via tools, at a right angle to the axis of rotation, lest the workpiece rip free. Thus, most work must be done axially, towards the headstock, or at right angles, but gently. When a workpiece is mounted with a certain axis of rotation, worked, then remounted with a new axis of rotation, this is referred to as "eccentric turning" or "multi-axis turning". The result is that various cross sections of the workpiece are rotationally symmetric, but the workpiece as a whole is not rotationally symmetric. This technique is used for camshafts, various types of chair legs. \|This section needs additional citations for verification. (April 2014)\| The smallest lathes are "jewelers lathes" or "watchmaker lathes", which are small enough that they may be held in one hand. The workpieces machined on a jeweler's lathe are metal. Jeweler's lathes can be used with hand-held "graver" tools or with compound rests that attach to the lathe bed. Graver tools are generally supported by a T-rest, not fixed to a cross slide or compound rest. The work is usually held in a collet. Common spindle bore sizes are 6 mm, 8 mm and 10 mm. The term W/W refers to the Webster/Whitcomb collet and lathe, invented by the American Watch Tool Company of Waltham, Massachusetts. Most lathes commonly referred to as watchmakers lathes are of this design. In 1909, the American Watch Tool company introduced the Magnus type collet (a 10-mm body size collet) using a lathe of the same basic design, the Webster/Whitcomb Magnus. (F.W.Derbyshire, Inc. retains the trade names Webster/Whitcomb and Magnus and still produces these collets.) Two bed patterns are common: the WW (Webster Whitcomb) bed, a truncated triangular prism (found only on 8 and 10 mm watchmakers' lathes); and the continental D-style bar bed (used on both 6 mm and 8 mm lathes by firms such as Lorch and Star). Other bed designs have been used, such a triangular prism on some Boley 6.5 mm lathes, and a V-edged bed on IME's 8 mm lathes. Smaller metalworking lathes that are larger than jewelers' lathes and can sit on a bench or table, but offer such features as tool holders and a screw-cutting gear train are called hobby lathes, and larger versions, "bench lathes". Even larger lathes offering similar features for producing or modifying individual parts are called "engine lathes". Lathes of these types do not have additional integral features for repetitive production, but rather are used for individual part production or modification as the primary role. Lathes of this size that are designed for mass manufacture, but not offering the versatile screw-cutting capabilities of the engine or bench lathe, are referred to as "second operation" lathes. Lathes with a very large spindle bore and a chuck on both ends of the spindle are called "oil field lathes". Fully automatic mechanical lathes, employing cams and gear trains for controlled movement, are called screw machines. Lathes that are controlled by a computer are CNC lathes. Lathes with the spindle mounted in a vertical configuration, instead of horizontal configuration, are called vertical lathes or vertical boring machines. They are used where very large diameters must be turned, and the workpiece (comparatively) is not very long. Various combinations are possible: for example, a vertical lathe can have CNC capabilities as well (such as a CNC VTL). Woodworking lathes are the oldest variety. All other varieties are descended from these simple lathes. An adjustable horizontal metal rail - the tool rest - between the material and the operator accommodates the positioning of shaping tools, which are usually hand-held. With wood, it is common practice to press and slide sandpaper against the still-spinning object after shaping to smooth the surface made with the metal shaping tools. There are also woodworking lathes for making bowls and plates, which have no horizontal metal rail, as the bowl or plate needs only to be held by one side from a metal face plate. Without this rail, there is very little restriction to the width of the piece being turned. Further detail can be found on the woodturning page. Most woodworking lathes are designed to be operated at a rate of between 200 and 1,400 revolutions per minute, with a rate slightly over 1,000 rpms being considered optimal for most such work, and with larger workpieces requiring slower rates. In a metalworking lathe, metal is removed from the workpiece using a hardened cutting tool, which is usually fixed to a solid moveable mounting, either a tool-post or a turret, which is then moved against the workpiece using handwheels and/or computer controlled motors. These (cutting) tools come in a wide range of sizes and shapes depending upon their application. Some common styles are diamond, round, square and triangular. The tool-post is operated by lead-screws that can accurately position the tool in a variety of planes. The tool-post may be driven manually or automatically to produce the roughing and finishing cuts required to turn the workpiece to the desired shape and dimensions, or for cutting threads, worm gears, etc. Cutting fluid may also be pumped to the cutting site to provide cooling, lubrication and clearing of swarf from the workpiece. Some lathes may be operated under control of a computer for mass production of parts (see "Computer Numerical Control"). Manually controlled metalworking lathes are commonly provided with a variable ratio gear train to drive the main lead-screw. This enables different thread pitches to be cut. On some older lathes or more affordable new lathes, the gear trains are changed by swapping gears with various numbers of teeth onto or off of the shafts, while more modern or expensive manually controlled lathes have a quick change box to provide commonly used ratios by the operation of a lever. CNC lathes use computers and servomechanisms to regulate the rates of movement. On manually controlled lathes, the thread pitches that can be cut are, in some ways, determined by the pitch of the lead-screw: A lathe with a metric lead-screw will readily cut metric threads (including BA), while one with an imperial lead-screw will readily cut imperial unit based threads such as BSW or UTS (UNF,UNC). This limitation is not insurmountable, because a 127-tooth gear, called a transposing gear, is used to translate between metric and inch thread pitches. However, this is optional equipment that many lathe owners do not own. It is also a larger change-wheel than the others, and on some lathes may be larger than the change-wheel mounting banjo is capable of mounting. There are some effects on material properties when using a metalworking lathe. There are few chemical or physical effects, but there are many mechanical effects, which include residual stress, micro-cracks, work-hardening, and tempering in hardened materials. Cue lathes function similar to turning and spinning lathes allowing for a perfectly radially-symmetrical cut for billiard cues. They can also be used to refinish cues that have been worn over the years. Glass-working lathes are similar in design to other lathes, but differ markedly in how the workpiece is modified. Glass-working lathes slowly rotate a hollow glass vessel over a fixed or variable temperature flame. The source of the flame may be either hand-held, or mounted to a banjo/cross slide that can be moved along the lathe bed. The flame serves to soften the glass being worked, so that the glass in a specific area of the workpiece becomes ductile, and subject to forming either by inflation ("glassblowing"), or by deformation with a heat resistant tool. Such lathes usually have two head-stocks with chucks holding the work, arranged so that they both rotate together in unison. Air can be introduced through the headstock chuck spindle for glassblowing. The tools to deform the glass and tubes to blow (inflate) the glass are usually handheld. In diamond turning, a computer-controlled lathe with a diamond-tipped tool is used to make precision optical surfaces in glass or other optical materials. Unlike conventional optical grinding, complex aspheric surfaces can be machined easily. Instead of the dovetailed ways used on the tool slide of a metal turning lathe, the ways typically float on air bearings and the position of the tool is measured by optical interferometry to achieve the necessary standard of precision for optical work. The finished work piece usually requires a small amount subsequent polishing by conventional techniques to achieve a finished surface suitably smooth for use in a lens, but the rough grinding time is significantly reduced for complex lenses. Metal spinning lathes In metal spinning, a disk of sheet metal is held perpendicularly to the main axis of the lathe, and tools with polished tips (spoons) or roller tips are hand held, but levered by hand against fixed posts, to develop pressure that deforms the spinning sheet of metal. Metal spinning lathes are almost as simple as wood turning lathes, and usually are. Typically, metal spinning requires a mandrel, usually made of wood, which serves as the template onto which the workpiece is formed (asymmetric shapes can be made, but it is a very advanced technique). For example, to make a sheet metal bowl a solid block of wood in the shape of the bowl is required, similarly to make a vase a solid template of the vase is required. Given the advent of high speed, high pressure, industrial die forming, metal spinning is less common now than it once was, but still a valuable technique for producing one-off prototypes or small batches where die forming would be uneconomical. Ornamental turning lathes The ornamental turning lathe was developed around the same time as the industrial screw-cutting lathe in the nineteenth century. It was used not for making practical objects, but for decorative work - ornamental turning. By using accessories such as the horizontal and vertical cutting frames, eccentric chuck and elliptical chuck, solids of extraordinary complexity may be produced by various generative procedures. A special purpose lathe, the Rose engine lathe is also used for ornamental turning, in particular for engine turning, typically in precious metals, for example to decorate pocket watch cases. As well as a wide range of accessories, these lathes usually have complex dividing arrangements to allow the exact rotation of the mandrel. Cutting is usually carried out by rotating cutters, rather than directly by the rotation of the work itself. Because of the difficulty of polishing such work, the materials turned, such as wood or ivory, are usually quite soft, and the cutter has to be exceptionally sharp. The finest ornamental lathes are generally considered to be those made by Holtzapffel around the turn of the 19th century. Many types of lathes can be equipped with accessory components to allow them to reproduce an item: the original item is mounted on one spindle, the blank is mounted on another, and as both turn in synchronized manner, one end of an arm "reads" the original and the other end of the arm "carves" the duplicate. A reduction lathe is a specialized lathe that is designed with this feature, and which incorporates a mechanism similar to a pantograph, so that when the "reading" end of the arm reads a detail that measures one inch (for example), the cutting end of the arm creates an analogous detail that is (for example) one quarter of an inch (a 4:1 reduction, although given appropriate machinery and appropriate settings, any reduction ratio is possible). Reducing lathes are used in coin-making, where a plaster original (or an epoxy master made from the plaster original, or a copper shelled master made from the plaster original, etc.) is duplicated and reduced on the reducing lathe, generating a master die. A lathe in which softwood, like spruce or pine, or hardwood, like birch, logs are turned against a very sharp blade and peeled off in one continuous or semi-continuous roll. Invented by Immanuel Nobel (father of the more famous Alfred Nobel). The first such lathes were set up in the United States in the mid-19th century. The product is called wood veneer and it is used for making plywood and as a cosmetic surface veneer on some grades of chipboard. Watchmakers lathes are delicate but precise metalworking lathes, usually without provision for screwcutting, and are still used by horologists for work such as the turning of balance staffs. A handheld tool called a graver is often used in preference to a slide mounted tool. The original watchmaker's turns was a simple dead-center lathe with a moveable rest and two loose head-stocks. The workpiece would be rotated by a bow, typically of horsehair, wrapped around it. Transcription or Recording lathes Transcription or Recording lathes are used to make grooves on a surface for recording sounds. These were used in creating sound grooves on wax cylinders and then on flat recording discs. Originally the cutting lathes were driven by sound vibrations through a horn and then later driven by electric current when microphones were used in recording. Many of these were professional models, but there were some used for home recording and were popular before the advent of home tape recording. Examples of lathes Belt-driven metalworking lathe in the machine shop at Hagley Museum Examples of work produced from a lathe National and international standards are used to standardize the definitions, environmental requirements, and test methods used for the performance evaluation of lathes. Selection of the standard to be used is an agreement between the supplier and the user and has some significance in the design of the lathe. In the United States, ASME has developed the B5.57 Standard entitled Methods for Performance Evaluation of Computer Numerically Controlled Lathes and Turning Centers, which establishes requirements and methods for specifying and testing the performance of CNC lathes and turning centers. - presentation by Tetsuo Tomiyama of Technical University Delft on the development of production technology including the Verbruggen Lathe - "Hints & Tips for Using a Lathe". “George Wilson’s” Hints and Tips - Publication date unknown. Lathes.co.uk. Retrieved 29 November 2010. - Parker, Dana T. Building Victory: Aircraft Manufacturing in the Los Angeles Area in World War II, p. 81, 123, Cypress, CA, 2013. ISBN 978-0-9897906-0-4. - Ernie Conover (2000), Turn a Bowl with Ernie Conover: Getting Great Results the First Time Around, Taunton, p. 16, ISBN 978-1-56158-293-8 - Holzapffel, Charles (1843–1897). Turning and Mechanical Manipulation Volume V. - Marlow, Frank (2008). Machine Shop Essentials: Q & A. Metal Arts Press. ISBN 978-0-9759963-3-1. - Oscar E. Perrigo. Modern American Lathe Practice. A New, Complete and Practical Work on the "king of Machine Shop Tools.", 1907. - Raffan, Richard (2001). Turning Wood With Richard Raffan. Taunton. ISBN 1-56158-417-7. - Joshua Rose. The Complete Practical Machinist: Embracing Lathe Work, Vise Work, Drills, etc., Philadelphia: H.C. Baird & Co., 1876; 2nd ed. 1885. - Sparey, Lawrence (1947). The Amateur's Lathe. Special Interest Model Books. ISBN 0-85242-288-1. - Woodbury, Robert S, (1961). History of the Lathe to 1850. Cleveland, Ohio: Society for the History of Technology. ISBN 978-0-262-73004-4. \|Wikimedia Commons has media related to Lathes.\| - Historical lathe archive - Medieval and Renaissance lathes - The history of the lathe - Early Wood-Working - Spring pole lathe - On ye art and mystery of Turning - Modern Machine Shop Practice a historic Victorian text describing lathe design, construction and use in 1880s. - The South Bend Lathe Library Make Magazine, November 16, 2011. Links to How to Run a Lathe and other publications by South Bend Lathe Works. - "The Forgotten Power Tool." Popular Science, December 1959, pp. 149–152. - "Disc Cutting and Recording Lathes." http://www.aes.org/aeshc/docs/recording.technology.history/lathe.html. - Complete Lathe Archive
\|present and past participles (il participio presente e passato) There are two participles, il participio presente (present participle) and il participio passato (past participle). Il participio presente is formed by adding -ante to the stem of -are verbs and -ente to the stem of -ere and -ire verbs. The present participle is used primarily as an adjective, agreeing with the noun it modifies. It is occasionally used as a noun and as a verb. Il participio passato is formed by adding -ato to the stem of -are verbs, -uto to the stem of -ere verbs, and -ito to the stem of -ire verbs. The past participle is much more commonly used than the present participle. It is always used with avere or essere to form tenses such as passato prossimo, trapassato prossimo and remoto, congiuntivo passato and trapassato, and so on.
What is Trichinosis? Trichinosis is an infection caused by a roundworm Trichinella spiralis or another species of Trichinella. Symptoms of this infection are diarrhea, abdominal cramps, muscle pain, and fever. Transmission occurs through consumption of contaminated raw or undercooked meat. Initially, the person suffers from nausea, diarrhea, abdominal cramps, then muscle pain, weakness, fever, headache and sometimes inflammation in other organs appear. A few weeks after the onset of the initial infection, the diagnosis can be confirmed by testing a blood sample for antibodies to Trichinella. Cooking meats well can kill Trichinella larvae, and freezing pork (except meat from wild animals) usually kills the larvae. Antiparasitic drugs, such as albendazole, can kill these worms in the intestines but not the larvae in the muscles, and pain relievers are needed to relieve muscle pain. Trichinella larvae live in the muscles of animals, typically pigs, wild boars, foxes, walruses, and many other carnivores. Sometimes the muscle tissue of horses fed meat supplements contains these larvae. Humans develop trichinosis when they eat raw, undercooked, or improperly squared meat from an animal that carries the parasite. In most cases, infection is due to the consumption of pork meat, especially in areas where these animals are fed raw meat scraps and rubbish, or from the consumption of wild boar meat, from bear or walrus. Worldwide, an estimated 10,000 cases of trichinosis occur each year. In the United States, fewer than 20 cases are reported each year. When meat containing Trichinella cysts is eaten, the cyst lining is digested, and the larvae released quickly develop into adult worms which reproduce immediately in the intestine. After mating, the male worms die and no longer play a role in the infection. Females, on the other hand, burrow into the intestinal wall and, after several days, begin to lay the larvae there. This larval production continues for about 4 to 6 weeks. Then the female either dies or is excreted from the body. The larvae are transported throughout the body by lymphatic and blood vessels. They enter the muscles and cause inflammation. Within 1 to 2 months, they form cysts that can live in the body for years. The dead larvae eventually get absorbed or calcify (harden). Some muscles, such as those of the tongue, eye and intercostal muscles, are more frequently infected. The larvae rarely form cysts in the heart muscle, but in about a quarter of people with trichinosis, an electrocardiogram (ECG) shows evidence of heart inflammation. Symptoms of trichinosis Symptoms of trichinosis vary depending on the stage of infection, the number of infesting larvae, the tissues involved and the general condition of the person. Many people with this condition are asymptomatic. Symptoms of trichinosis appear in 2 stages: - Stage 1: The intestinal infection appears 1 to 2 days after eating contaminated meat. Symptoms may include nausea, diarrhea, abdominal cramps, and a slight fever. - Stage 2: Symptoms of larval invasion of muscles usually begin about 7 to 15 days later. Symptoms are muscle pain and tenderness, fatigue, fever, headache, and swelling of the face, especially around the eyes. The pain is often more intense in the muscles used to breathe, cough, speak, chew and swallow. A non-itchy rash may appear. In some people, the whites of the eyes turn red, the eyes burn and become sensitive to bright light. In the presence of a large number of larvae, inflammation of the heart, brain, and lungs may develop. It can be responsible for heart failure, cardiac arrhythmias, seizures and serious breathing problems. The death is exceptional. If left untreated, most symptoms go away by the third month of infection, although vague muscle pain and asthenia may persist longer. Diagnosis of trichinosis - Blood tests to look for antibodies against the parasite - Trichinosis cannot be diagnosed by microscopic examination of the stool. Testing a blood sample for antibodies to Trichinella spiralis is fairly reliable, but the test is not positive until 3 to 5 weeks after symptoms appear. If the results are negative, the doctor will base his diagnosis of trichinosis on the symptoms and on the increased level of eosinophils (a type of white blood cell) in the blood. The test for antibodies is repeated weekly for several weeks to confirm the diagnosis. - A muscle tissue biopsy (in which a sample of tissue is taken and examined under a microscope), taken after the second week of infection, may show larvae or cysts, but is rarely necessary. Prevention of trichinosis Trichinosis is prevented by properly cooking meats, especially pork and pork products, at a temperature above 71 ° C, until they are golden all over. Alternatively, in domestic pigs that are less than 15 cm thick, the larvae can be killed by freezing the pig at -5 ° C for 20 days. Freezing is not recommended for meat from wild animals, as they can be infected with Trichinella species that are not killed by low temperatures. Smoking, curing, or cooking in the microwave is not entirely effective in killing the larvae. Meat grinders and other items used to prepare raw meat should be thoroughly cleaned. It is also important to wash your hands with soap and water. Also, do not feed pigs raw meat. Mebendazole or albendazole (antiparasitic drugs that kill adult worms) For muscle pain, analgesics For severe infections, corticosteroids Oral treatments with mebendazole or albendazole kill adult worms in the intestines but do not have much effect on cysts in the muscles. Pain relievers (such as nonsteroidal anti-inflammatory drugs [NSAIDs]) can relieve muscle pain. To reduce inflammation during severe infections, corticosteroids (such as prednisone) may be prescribed. Most patients with trichinosis recover completely. Key points of trichinosis - Humans are infected with Trichinella by eating meat that is raw, undercooked, or prepared from infected animals, most commonly pork, wild boar, or bear. - The larvae disencyst in the small intestine, enter the mucosa and develop into adults which release live larvae; the larvae migrate through the bloodstream and lymphatics and become encysted in striated skeletal muscle cells. - Symptoms begin with gastrointestinal irritation followed by periorbital edema, muscle pain, fever, and eosinophilia. - Manifestations gradually subside by about month 3, when the larvae are completely encysted, although relative muscle pain and fatigue may persist. - Diagnose by enzyme immunoassay. - Treat symptoms (eg, with pain relievers and prednisone for allergic manifestations or for central nervous system involvement); anthelmintics kill adult worms, but once the larvae encyst in the skeletal muscle, treatment may not eradicate them or eliminate the associated symptoms. - Thorough cooking of pork and wild animal meat can prevent trichinosis. Photo description: Trichinella spiralis. Shows muscle tissue infected with Trichinella spiralis larvae, the nematode parasite that causes trichinosis. The largest larva shown here has a rope length of about 22.5 micrometers, and a diameter of about 5 micrometers.
20 Most Endangered Butterfly Species Have you ever stopped to admire the delicate beauty of a butterfly? These tiny creatures are much more than just a pretty sight; they’re also essential to our ecosystem. Unfortunately, a startling number of butterfly species are under threat – let’s take a closer look at 20 of the most endangered. Miami Blue (Cyclargus thomasi bethunebakeri) Miami Blue is a butterfly species rich in history, heavily linked to Florida. It’s hard to spot, but if you do, you’re in for a treat. - Habitat: Mostly found in the coastal areas of southern Florida. - Appearance: Blue wings with black borders, and an orange-colored underside with black spots. - Size: Pretty small, around 1 inch (2.54 cm) in length. - Diet: Adult Miami Blues drink nectar from various plants, with larvae feeding on balloon vine. - Reproduction: Females lay their eggs on budding balloon vine leaves. - Lifespan: They typically live a few short weeks. - Host Plants: Mainly balloon vine (Cardiospermum corindum), but also blackbead and nickerbean. Sadly, this species has faced numerous threats, from habitat destruction to pesticide exposure. Miami Blues are among the world’s most endangered butterflies, a sad reality we must work to change. Saint Francis’ Satyr (Neonympha mitchellii francisci) Encounter a kind of beauty that stands on the brink of extinction- the Saint Francis’ Satyr butterfly. - Habitat: These winged jewels are mainly discovered in wetlands and grasslands around Fort Bragg, North Carolina. - Appearance: Saint Francis’ Satyrs flaunt a beautiful motif of light brown and orange sectors overlaid by black spot patterns. - Size: The delicate creature spans across approximately an inch and a half (3.8cm). - Diet: Sustenance for this butterfly is derived from nectar they extract from plants. - Reproduction: Puzzling to scientists, these butterflies reproduce only in disturbed habitats, not pristine ones. - Lifespan: The often short-lived Saint Francis’ Satyr sees a lifespan from egg to adult to be up to a year. - Host Plants: The caterpillar stage cherishes feeding on various sedges. Discover more about this rare beauty and efforts put into conservation, and we’ll find ourselves closer in hand to protect wavering species. Oregon Silverspot (Speyeria zerene hippolyta) Oregon Silverspot butterfly is considered one of the most endangered species, with its populations dramatically declining. - Habitat: They’re usually found along the Pacific Northwest coast; in a particular tall grass prairie habitat, called “salt-spray meadows.” - Appearance: They don a brilliant orange-brown colour with stunning silver spots beneath their wings. - Size: This butterfly is unassumingly small in size with a length of 5 cm (about 2 in). - Diet: In caterpillar state, the diet includes violets as primary food; Adult butterflies feed on nectar from flowers. - Reproduction: Eggs are laid in late summer, where their larvae feed on violets only post winter hibernation. - Lifespan: This species has one short generation per year, lifespan ranging from a few weeks to a month. - Host Plants: The genus viola, primarily early blue violet, is the host plants for Oregon Silverspot. This explains their strong bond with grassland habitats where these plants thrive. Laguna Mountains Skipper (Pyrgus ruralis lagunae) The Laguna Mountains Skipper is one butterfly you should be familiar with. Sadly, it’s on the brink of extinction. Let’s learn more about this flying wonder: - Habitat: Exclusively in San Diego County, California. Found particularly in meadows and open woodlands. - Appearance: Characterized by distinct brown and orange markings on its wing undersides. - Size: Quite tiny, with an average wingspan of just about 1.25 inches (3.18 centimeters). - Diet: As caterpillars, they feed on a specific plant, spreading lomatium. Adult butterflies prefer nectar from a variety of flowers. - Reproduction: There’s a solitary annual generation each year, typically emerging in April. - Lifespan: Short-lived, usually around a week for adults. However, the total lifespan including the larval stage is about a year. - Host Plants: The Laguna Mountains Skipper caters rely solely on the spreading lomatium plant during the larval stage for survival. This butterfly is truly an icon of its unique habitat. Sadly, habitat destruction poses a significant threat to its existence. Uncompahgre Fritillary (Boloria acrocnem) The Uncompahgre Fritillary (Boloria acrocnem) is among the more unique butterfly species around. As fascinating as it may be, it’s sadly a vanishing sight. Here are some key facts about this endangered butterfly: - Habitat: This butterfly calls the high alpine meadows of Colorado’s San Juan Mountains in the United States home. - Appearance: Sporting a silver-spotted coloration on an orangish-brown underwing, it’s a sight to behold. - Size: It’s quite petite, just about 1 inch (2.5 cm) wide! - Diet: As adult butterflies, they love the nectar from alpine flowers. - Reproduction: Females lay their eggs on the host plant, usually once a year. - Lifespan: Short-lived adult life, survives only a few weeks in summer. - Host Plants: They have a special preference for plants like Rosaceae and Asteraceae. Through the beauty of this butterfly, we learn how even the smallest creatures play vital roles in our ecosystem. Fender’s Blue (Plebejus icarioides fenderi) Let’s talk about a little, blue-winged wonder – Fender’s Blue butterfly. Rightfully named after its stunning, iridescent blue wings, this species is a true gem. However, its beauty is declining, and it’s now classified as endangered. Here is a snapshot of the Fender’s Blue butterfly: - Habitat: Favouring prairies, fields, and meadows of the Pacific Northwest, particularly Oregon. - Appearance: An attractive butterfly, males boast an iridescent silvery-blue hue while females exhibit a duller brown shade. - Size: A modest little creature, average wingspan ranges from a tiny 0.75 to 1.00 inch (1.9–2.5 cm). - Diet: Primarily, they feed on flower nectar but caterpillars thrive on lupine leaves. - Reproduction: Mating period begins late spring, and females lay eggs on Kincaid’s lupine plants. - Lifespan: Short-lived, these butterflies survive only about a week. - Host Plants: The endangered Kincaid’s lupine serves exclusively as the Fender’s Blue larva host plant. The reduction of its habitat has severely affected the survival of this innocuous creature. Let’s dive deep into why more species face this risk. Palos Verdes Blue (Glaucopsyche lygdamus palosverdesensis) The Palos Verdes Blue is a dazzling butterfly species unfortunately facing extinction. This butterfly is endemic to a small region in California. - Habitat: It’s found only in the Palos Verdes Peninsula area, thriving in coastal sage scrubs. - Appearance: Male Palos Verdes Blue butterflies have a vibrant blue upper side, while females have a duller brownish-blue hue. - Size: These are tiny creatures, with a wingspan of just 1 inch (2.5 centimeters) across. - Diet: Butterflies sip nectar from flowers. This species particularly prefers locoweed and deerweed. - Reproduction: Females lay eggs on the host plants. After hatching, caterpillars feed on these plants. - Lifespan: Adults live for a brief couple of weeks, while larvae can live for up to 10 months. - Host Plants: Locoweed and deerweed are their primary host plants. Protection of these plants is now integral in saving this species. So, preserving the delicate ecosystem of the Palos Verdes Blue is crucial for this small, yet beautiful creature’s survival. Bay Checkerspot (Euphydryas editha bayensis) The Bay Checkerspot is something you kindly need to understand. It is somewhat tricky given their endangered status. - Habitat: This butterfly thrives in grasslands, preferably with native bunch grasses. - Appearance: The Bay Checkerspot is distinguished by the intricate multicolored pattern of spots and bands on its wings. - Size: Generally, these delicate butterflies have a wingspan of about 2 inches (5 cm). - Diet: As caterpillars they enjoy plantain species but, in their transformed state, they drink nectar from native wildflowers. - Reproduction: Females lay their eggs primarily on dwarf plantain plants. - Lifespan: These stunning butterflies have a remarkably short lifespan of around two weeks in their adult phase. - Host Plants: The dwarf plantain and owl’s clover are essential for the Bay Checkerspot’s reproduction. Its unique lifecycle sings to its dependence on these host plants. Isn’t it fascinating to learn about these little creatures and their struggle for survival? Mission Blue (Icaricia icarioides missionensis) The Mission Blue butterfly is one of a kind and not in a good way, as it teeters precariously on the brink of extinction. Now let’s dive into what makes this butterfly species unique: - Habitat: Call northern California, especially the San Francisco Bay Area, home. Sadly, urban development has led to a drastic shrinkage of their habitat. - Appearance: Eye-catching males boast a vivid hue of blue, while females are brown on top. Both genders have distinctive rows of black spots. - Size: Small, with a wingspan of just about an inch, or around 2.5 centimeters. - Diet: Primarily lupine plants – it prefers to feed on their nectar in adult form. - Reproduction: Females lay eggs on lupine plants, the caterpillar’s host. Mating season is generally once a year. - Lifespan: Like many butterflies, their lifespan is short, normally only a few days to a week. - Host Plants: Lupines, to be specific. Without them, Mission Blues can’t complete their life cycle, leading to a sharp population decline. Lange’s Metalmark (Apodemia mormo langei) Meet the Lange’s Metalmark, one of the most endangered butterfly species. The beauty of its orange-red wings with black spots is undeniably breathtaking. Here are some quick facts about this remarkable insect: - Habitat: Primarily found in the Antioch Dunes in California. - Appearance: Orange-red wings with black spots. - Size: An adult Lange’s Metalmark has a wingspan of about 1.5 inches (3.8 cm) - Diet: Adults sip nectar from flowers while the caterpillar depends on the Antioch Dunes Buckwheat for food. - Reproduction: Females lay eggs on the underside of leaves of their host plant which the larvae later feed on. - Lifespan: The typical lifespan is 10 to 14 days for adults. - Host Plants: Primarily dependent on the Antioch Dunes Buckwheat plant. In spite of its brief lifespan, the Lange’s Metalmark plays a vital role in the ecological balance. Yet, urban development and invasive species are pushing it to the brink of extinction. Island Marble (Euchloe ausonides insulanus) Island Marble is a type of butterfly listed as one of the world’s most threatened species. This white and yellow butterfly has a captivating characteristic that deserves your attention. - Habitat: Primarily on San Juan Island, Washington. - Appearance: Underwings are marbled yellow and green, hence the name Island Marble. - Size: They are small with a wingspan averaging 1.25 inches (3.2 cm). - Diet: Adult butterflies feed on flower nectar while the caterpillars eat leaves. - Reproduction: Female butterflies lay a single egg on a host plant at a time. - Lifespan: Like many adult butterflies, an Island Marble’s lifespan is short – typically a few weeks. - Host Plants: The butterfly’s larvae prefer the Mustard family, notably Menzies’ pepperweed and field mustard. Conservation efforts are in effect to protect and nurture the Island Marble, which includes protecting its vital host plants. Let’s hope the Island Marble can continue to thrive in its Washington home. San Bruno Elfin (Callophrys mossii bayensis) The San Bruno Elfin is one of the more exotic butterfly species. Let’s find more about it: - Habitat: They specifically live in the coastal scrublands of the San Bruno Mountains in California. - Appearance: This butterfly has a unique brown color, with occasional orange scales on the hind wings, making it easily identifiable. - Size: Small in size, they range from 1 to 1.5 inches (2.5 to 3.8 cm) in wingspan. - Diet: As larvae, they feed on Stonecrop. Adult butterflies feed primarily on tree sap and rotting fruit instead of nectar. - Reproduction: Females lay eggs in March and April. The caterpillars hatch and feed on their host plant. - Lifespan: After surviving the winter as larvae, the adults live up to 2 weeks, typically in March and April. - Host Plants: Sedum spathulifolium or Broadleaf stonecrop serve as the primary host plant for the San Bruno Elfin’s larvae. Dakota Skipper (Hesperia dacotae) The Dakota Skipper is one remarkable butterfly species that faces significant threats. Now, let’s delve into understanding this fantastic creature more intimately. - Habitat: They traditionally dwell in tallgrass prairies, which unfortunately have seen a drastic reduction in recent years. - Appearance: They’re quite appealing with a warm brown-orange color sprinkled with some black spots. - Size: An adult Dakota skipper has a wing span of about 1 inch (2.54 centimeters). - Diet: Adult skippers feed on nectar from several prairie flowers. - Reproduction: They lay eggs on or near the host plants, and the hatching caterpillars feast on these plants. - Lifespan: Their lifecycle is approximately one year. Adults live for around one week during which they reproduce. - Host Plants: Dakota Skippers are fairly exclusive and favor ‘Switchgrass’, ‘Prairie Bluestem’ or ‘Little Bluestem’ grasses for their growth and development. Just imagine, a creature so tiny and lovely, holding onto life tenuously in the rapidly evolving world. We must do our part to help them survive. Poweshiek Skipperling (Oarisma poweshiek) Let’s meet the Poweshiek Skipperling (Oarisma poweshiek), a tiny but massively significant butterfly. - Habitat: Mostly found in native prairie habitats, particularly tallgrass prairie. - Appearance: A small, brown, and unmarked butterfly with a lot of charisma. Look for fringe on the wings; it’s a distinctive feature. - Size: Average wingspan is around 1 inch (2.54 cm) only. - Diet: As adults, they intake nectar from flowering plants. The larvae munch on grasses. - Reproduction: Females usually lay eggs on the host plants in the mid-summer. - Lifespan: Their lifecycles encompass an entire year. Adults have a brief lifespan of a week or two. - Host Plants: They prefer certain species of grasses, especially Prairie Dropseed (Sporobolus heterolepis). Isn’t this butterfly’s life interesting? In the midst of its beauty lays a tale of survival, which isn’t always easy. Said to be fewer than 500 in population, the Poweshiek Skipperling is, tragically, on the brink of extinction. Schaus Swallowtail (Papilio aristodemus ponceanus) Get ready to learn about this stunning, yet critically endangered butterfly species, the Schaus Swallowtail. - Habitat: Mainly confined to a few tropical hardwood hammocks in the Florida Keys, in the US. - Appearance: It boasts a beautiful combination of yellow and black, with a set of tails that mimic the look of its head, a handy deceptive tool against predators. - Size: With a wingspan of approximately 3.1-3.5 inches (7.9-8.9 cm), this butterfly is a sight to behold. - Diet: The caterpillars feed on plants like Torchwood and the adults enjoy flower nectar. - Reproduction: Females lay pale green eggs singularly on new growth of the host plants. - Lifespan: Typically, around two months, but the Schaus Swallowtail creates several generations in a single year. - Host Plants: Primarily the use Wild lime and Torchwood. Loss of habitat and other, vicious realities of today’s world have critically endangered this butterfly species. So, let’s all remember it’s possible to contribute even in our small ways to their conservation. Mount Charleston Blue (Icaricia shasta charlestonensis) Our attention draws to Mount Charleston Blue butterfly, an absolute feast for the eyes. However, it’s a pleasure we may soon be deprived of, unless we act. - Habitat: This unique species calls the high-elevation forests of Nevada’s Spring Mountains home. - Appearance: Characterised by its exquisite bright blue color, it distinguishes itself from others with noticeable black margins on its wings. - Size: This species isn’t size-threatening, typically measuring from 16mm to 31mm. - Diet: As larvae, they munch on host plants, while adult butterflies consume nectar. - Reproduction: They lay their eggs in the summer. The larvae hibernate during winter and mature in the spring. - Lifespan: Quite short-lived, they survive roughly a week as adults. - Host Plants: Mainly the Torrey’s Milkvetch plant. The Mount Charleston Blue relies heavily on these host plants, resulting in a symbiotic relationship that ultimately, plays a significant role in maintaining biodiversity. Quino Checkerspot (Euphydryas editha quino) You’d be lucky to spot a Quino Checkerspot. Once thriving in southern California, this colorful species is now critically endangered due to habitat loss and climate change. Have a look at some features of this special butterfly: - Habitat: Quino Checkerspots thrive in California’s open, sunny areas with grassland. - Appearance: Like an artistic masterpiece, its wings flaunt patterns of red, white, and black. - Size: A petite butterfly, measuring a wingspan of 1 to 1.5 inches (2.5 to 3.8 cm). - Diet: As caterpillars, they love to munch on dwarf plantain. After metamorphosis, they feed on flower nectar. - Reproduction: Female Quino lay their eggs on the underside of leaves where the caterpillars can feed after hatching. - Lifespan: Their journey from egg to adult lasts one year. Weather depending, adults may live 2 weeks to a month. - Host Plants: Plantains (Plantago erecta) and snapdragons (Antirrhinum spp.) are their preferred host plants where females lay eggs. Endeavors to protect and recover this species are ongoing. Providing it a chance at life is all it needs! Taylor’s Checkerspot (Euphydryas editha taylori) Meet the Taylor’s Checkerspot butterfly. This species is quite unique in its characteristics. Though small in size, it’s undeniably striking to look at. - Habitat: Originally, you’d find it throughout the Pacific Northwest, but now it’s limited to Oregon, Washington, and one spot in British Columbia. - Appearance: With its wings displaying a dazzling pattern of orange, white, and black squares, it surely leaves an impression. - Size: Small but not insignificant, it spans around 1.5″ or 3.8 cm. - Diet: As a caterpillar, it’s fond of eating lance-leaf plantain. However, the adult prefers flower nectar. - Reproduction: Interestingly, a female can lay over 1,000 eggs in her lifetime! - Lifespan: Sadly, life is fleeting for the Checkerspot. It lives only one year. - Host Plants: It mostly depends on the plantago or Potentilla flower during its larval stage for both food and shelter. Let’s keep hoping that efforts to save this delightful little creatures prove successful. Callippe Silverspot (Speyeria callippe callippe) Have you ever spotted the Callippe Silverspot butterfly? This fascinating creature was once abundant but is now classified as endangered. - Habitat: It’s known to reside in the sunny hills of California. - Appearance: This butterfly boasts bright orange and black markings. It’s a sight to behold. - Size: With a wingspan ranging from 3.75 cm to 6.25 cm (1.5 in to 2.5 in), it’s impressively big. - Diet: Adult butterflies feed on nectar, while the caterpillars munch on leaves. - Reproduction: Females lay eggs on the host plants, which hatch into larvae after a week. - Lifespan: It lives for about a year, but this life is threatened due to habitat loss. - Host Plants: Viola pedunculata, or the yellow pansy, is the primary food for Callippe Silverspot larvae. Now you’re acquainted with the Callippe Silverspot, isn’t it disheartening to know that it’s endangered? Consider that next time you’re exploring California’s hillside trails. Bartram’s Hairstreak (Strymon acis bartrami) The last on our list but not the least significant, we have the Bartram’s Hairstreak, a butterfly species that’s facing an increased risk of extinction. - Habitat: This butterfly is native to South Florida, specifically Pine Rockland habitats. This habitat is rare and endangered, just like the butterfly itself. - Appearance: Characterized by its muted gray color, tinged with blue, and adorned with black and white spots on the wing edges. - Size: These butterflies are relatively small, boasting a wingspan of only 1 to 1.5 inches (2.5 to 3.8 cm). - Diet: The adults sustain on nectar, primarily from herbs and shrubs. - Reproduction: Females lay eggs on new growth of their host plants. The caterpillars feed on the leaves. - Lifespan: They typically live for 1 to 2 weeks as adults. - Host Plants: The primary host plant is locally known as locust berry or by scientific name; Byrsonima lucida. Unique and beautiful, the combination of habitat loss and limited host plants puts the Bartram’s Hairstreak at risk. In conclusion, it’s heartbreaking to see that these 20 butterfly species are on the brink of extinction. These creatures not only add beauty to our world, but they also play crucial roles in our ecosystem. Please, leave a comment and let’s discuss what we can do individually or collectively to help these beautiful species recover.
Accretions of terranes. The development of a series of mountain belts along a continent's margins increases the size of the continent by adding new continental crust (accretion). In most cases, a continent consists of an older core (craton) surrounded by progressively younger rocks. Mountain ranges are sometimes called tectonostratigraphic terranes, or just terranes, which represent regions of geologic continuity distinct from neighboring mountain ranges. Terranes can range up to thousands of square kilometers in area. Accreted terranes are those that appear to have formed in place along a continent's margin through accumulation and orogeny. A suspect terrane is one that does not fit the regional pattern or has conflicting age dates; an exotic terrane is one that did not form naturally through accretion and has likely collided with the continental margin. Exotic terranes have distinctive rock types, metamorphic and structural histories, and ages of formation. Paleomagnetic data can sometimes be used to reconstruct an exotic terrane's path of migration. Such terranes can be island arcs, microcontinents such as New Zealand, or rifted fragments of distant continents. North America is composed of over fifty distinct geologic terranes; twelve of these have been accreted to western North America during the past 200 million years.
Today is Haitian Flag Day and while everyone is celebrating and posting pictures of their flag, how much do you know about the history behind it? According to This great article For a country’s citizens, the national flag is indisputably a symbol of general pride. They would consider any offense to their flag to be an offense to their country. Beyond being an icon though, a flag’s origin can often say a lot about a nation’s social make-up or history. Haitians feel no different and even reserve a special day to honor it. That day is May 18th. In Haiti, Flag Day is a major national holiday celebrated with great fanfare on the grounds of the national palace. Haitians in the Diaspora also observe Flag Day. In The United States for example, teenagers whether in High School give homage to the red and blue by carrying it around with them or on their persona for at least a week. Haiti’s flag’s origin is tightly linked to a history of struggle for freedom. In the early days of revolt in St. Domingue, the slaves did not have a flag. However, they did notice that their former masters were using the French Flag. From 1791 to about 1793, the revolt became more widespread and gave rise to a number of large groups still fighting independently. In those times, each main leader would use any piece of cloth as a flag. Slowly the slave movement found some synergy and came to follow the leadership one main person: Toussaint Louverture. Realizing that you cannot fight three enemies at the same time, Toussaint and the army of revolted slaves fought successively for the Spanish against the French (1793-1794), for the French against Spain and England (1794-1802) and ultimately against France. As such, he carried the color of whichever European power he was fighting for. He later realized that it was silly to use the same flag as the enemies. He then invented his own flag, which was a white piece of cloth with a Negro head to represent the blacks. After Toussaint’s deportation, The Indigene Army went back to the French flag for a while. A little explanation is needed here: The French flag, as we know it now is a product of the French Revolution. It was made up of Red and Blue, the colors of the City of Paris, and a band of white representing the monarchy (La Nation, la Loi et le Roi –). On the white portion of the flag was the emblem of the French Republic. The Revolution of St. Domingue was in some ways motivated by the French Revolution and for years, the masses main objectives were for freedom and better treatment. To them, the French Flag represented the ideals of Liberty and Fraternity. They hoped that those same principles would be applied to them, non-whites According to Thomas Madiou (1814-1884), a renowned historian of the 19th Century; they also saw in that flag a symbol of blacks, whites and mulattoes living in harmony. Therefore, carrying the French was not stupidity, but rather an expression of their ideals. As time went on though, a break with France seemed inevitable and to symbolize their resolve of never fighting for the metropolis again, they had removed the French arms from the blue white and red flag they were using. As early as February 1803 however, Petion, leader of the mulattoes and Dessalines had decided to create a unique flag to represent their troops. Thus, starting with the French Flag made up of three blue, white and red bands placed vertically respectively; Dessalines removed the white and created the first unofficial flag with blue and red bands placed vertically. By so doing, he also wanted to impart on the French the message that they had lost that colony forever. To them the blue symbolized the mulattos and the blacks while the red symbolized their blood. While this flag was observed in most part of the country; Cangé, a general in the south used a black and red flag instead. By 1803 as we saw, the leaders of the free slaves and the men of color had decided to fight for the creation of an independent nation.Before marching on Port-Republicain (Port-au-Prince’s name at that time) Dessalines and Petion needed to make a strong statement. On May 18, 1803, in the city of Arcahaie, not far from Port-au-Prince, they agreed on an official flag, with blue and red bands placed vertically. Blue and red placed vertically respectively. A lady named Catherine Flon sewed Haiti’s first flag. On Independence Day however, January 1st 1804, the flag was modified again. The Blue and Red bands were placed horizontally this time, with the blue band on top of the red band. This was the first flag of the independent republic. In 1805, shortly after Jean-Jacques Dessalines proclaimed himself emperor, the Haitian flag color was changed to black and red bands placed vertically respectively. After the emperor’s death, in 1806, the country will be divided into two republics for 14 years. Henri Christophe, in the northern part kept the flag that Dessalines used. In the south and the western part of the country, Alexandre Petion went back to 1804’s flag that was blue and red only this time he added the white squared portion that included the country arms and the famous phrase “L’UNION FAIT LA FORCE“, meaning that through unity we find strength. That flag was in use until 1964 when Papa Doc Duvalier brought back the black and red flag of Dessalines and added a modified version of the arms of the Republic. On February 25 1986, after the fall of Baby Doc and the Duvalier regime, the people requested that the red and blue flag be brought back. The constitution of 1987 describes the new flag in these terms: The emblem of the Haitian Nation shall be a flag with the following description: a) Two (2) equal-sized horizontal bands: a blue one on top and a red one underneath. b) The coat of arms of the Republic shall be placed in the center on a white square. c) The coat of arms of the Republic will be a Palm tree surmounted by the liberty cap and under the palms a trophy with the legend: In Union there is Strength. That is the flag used until today.
Manitoulin is relatively protected by Lake Huron so the climate trends we’re experiencing will not likely be a huge detriment to crops and only minor changes would be required. The biggest change that may be required is increasing the number of fields with tile drainage to deal with increased spring precipitation. With tile drainage, crops can be planted earlier in the spring so they have enough time to establish root systems to help deal with summer drought conditions. Hay is the most grown crop on Manitoulin and it along with winter wheat are particularly susceptible to winter kill. With increased winter precipitation in the form of rain, the ground could be covered in layers of ice rather than the typical snow pack. This prevents oxygen from getting to the plants and could lead to increased winter kill. An increase in the freeze thaw cycle can cause the roots of overwintering hay to be drowned. While the winters may be more difficult for hay, a warmer and wetter spring could be beneficial in terms of growth. - Preventative measures could include increased seeding in the Fall as well as earlier planting. A decrease in summer precipitation or an increase in summer evaporation due to increased air temperatures could slow the growth and reduce the yield of these plants. Barley and oats grow best in cooler climates so an increase in summer air temperatures could also reduce growth on its own regardless of precipitation. - Preventative measures could include earlier planting to avoid extreme heat and lack of precipitation. - If springs are expected to be extremely wet having tiled land would also be a benefit. Legumes establish deeper roots and will be better suited to dealing with summer drought conditions. However, legumes are also susceptible to winter kill and it may be necessary to keep an updated stand that's tilled every 4-5 years. The number of frost-free days and the number of growing degree days (GDD) are predicted to increase across Manitoulin which is an overall benefit for crop agriculture. - From 1981-2010 Gore Bay had on average 209 frost free days per year. By the 2080’s it is expected there will be on average 276 frost free days. - From 1981-2010 Gore Bay had on average 1813.7 GDD. By the 2080’s it is expected there will be on average 3006.4 GDD per year. - From 1981-2010 Little Current had on average 204 frost free days per year. By the 2080’s it is expected there will be on average 273 frost free days. - From 1981-2010 Little Current had on average 1741.7 GDD. By the 2080’s it is expected there will be on average 2917 GDD per year. - From 1981-2010 South Baymouth had on average 218 frost free days per year. By the 2080’s it is expected there will be on average 289 frost free days. - From 1981-2010 South Baymouth had on average 1761.4 GDD. By the 2080’s it is expected there will be on average 2988 GDD per year. - Heat stress is unlikely to be a major health issue unless cattle have zero access to shade. The water consumption of cattle may increase and more grazing may occur during cooler periods of the day. If it is too hot bulls will not breed and the calving season may be delayed. Planting trees or allowing for bush access to provide shade could be a preventative measure - If calving occurs in the winter or spring and there is a lot of temperature fluctuation, calves may be more susceptible to illness and respiratory issues like pneumonia. Wetter springs could also lead to an increase in scours, naval infection and foot rot. Wet springs lead to more flies which are stressor for cattle and if extreme summer temperatures are added on top of that as well as moving cattle, it could lead to a reduction in weight gain. - Higher temperatures could mean that sheep require shearing twice a year as opposed to once in order to reduce heat stress. If the spring is also particularly wet there will be more flies which lay eggs in the wool of sheep and the maggots could begin eating the sheep.
A logged forest in the Amazon. By Steve Lundeberg A collaboration led by Ekena Rangel Pinagé (Oregon State University) has used very-high-resolution satellite imagery to develop a machine learning model that aims to improve climate scientists’ ability to estimate aboveground carbon stocks in the Amazon. Findings of the study were published in the journal Carbon Balance and Management. Covering more than 2.5 million square miles in South America, the Amazon is the largest of the world’s tropical forests, which play huge ecological roles for the planet despite covering less than 10% of the Earth’s land area. More than half of all carbon stored in aboveground biomass is sequestered in tropical rain forests, which are also home to greater than 60% of all terrestrial species. Second growth and degraded forests now cover more area than intact forests, but scientists say the full extent of tropical forest degradation is not completely known. “Tropical forests are critical for the global carbon budget, and forest degradation through fires and selective logging has been widespread in the Amazon,” said Ekena. “What’s more, there has been a lot of uncertainty regarding land cover classification – categorizing which areas have been logged, which have burned, which are intact forest, which are second growth, etc.” Ekena and collaborators used commercially available satellites that generate very-high-resolution (VHR) images with pixels at the scale of three square meters. By comparison, satellite imagery produced by Landsat, a long-running partnership between NASA and the U.S. Geological Survey, has a resolution of 30 square meters. “We also used laser sensors on an aircraft to estimate how much carbon forests lose when they are degraded,” she said. “Deforestation and forest degradation are both substantial sources of carbon to the atmosphere.” The scientists worked at three study sites in the Brazilian Amazon; two of them were mixtures of intact forest with logged tracts or burned areas, while the third also included some parcels that had been converted to agriculture. By combining VHR images and laser sensor data, researchers could attribute aboveground carbon stock changes to specific types of forest degradation and determine how much of the greenhouse gas carbon dioxide was released to the atmosphere by either logging or fire events. Burned and fragmented forest in the Amazon. “Our machine learning method was able to distinguish degraded forests from intact forests 86% of the time,” Ekena said. “Sometimes it confused logged forests with intact forests, but it is very good at identifying burned areas. And to most precisely determine the impact of forest degradation on carbon stocks, our team considered that the forest degradation classes – logged or burned – come with uncertainties, as do their corresponding carbon stock changes.” The scientists found that building those uncertainties into the modeling led to lower estimates of mean carbon density in two of the three test sites by as much as 6.5%. That means earlier estimates that did not consider the inherent uncertainties may have been over-optimistic. The study also suggests logged forests contain almost the same amount of carbon as intact forests, but that fire can reduce the amount of a forested area’s carbon by as much as 35%. “Our findings indicate that, when attributing biomass changes to forest degradation, estimates need to account for the uncertainty that’s part of assigning a degradation classification,” Ekena said. “It’s important to fully understand the consequences of forest degradation on the carbon budget and the gains that might occur through regeneration.” Effects of forest degradation classification on the uncertainty of aboveground carbon estimates in the Amazon Ekena Rangel Pinagé, Michael Keller, Christopher P. Peck, Marcos Longo, Paul Duffy & Ovidiu Csillik
Metamorphic rocks are one of the three types of rocks found on earth. The other two are sedimentary and igneous rocks. Metamorphic rocks account for 12% of the earth’s land surface and comprise a large part of the earth’s crust. How are Metamorphic Rocks formed? Metamorphic rocks are created from existing rocks. These rocks are not deposited like igneous rocks. This conversion process is known as metamorphism. Some metamorphic rocks are also created as a result of metasomatism. The transformation or conversion happens when an existing rock undergoes extreme temperature and pressure. This rock is known as original rock, protolith, or parent rock. The temperature and pressure are usually above 150 to 200°C (300 to 400°F) and 100 megapascals (1,000 bar). The exposure to higher temperature and pressure causes big changes in the rock, and it recrystallizes to a new texture and mineral composition. The rock remains solid during the transitional change. Types of Metamorphic Rocks Metamorphic rocks are usually of two types. Foliated Metamorphic Rocks: Foliated metamorphic rocks have a layered or banded appearance. This appearance results due to exposure to heat and directed pressure. Common foliated rocks are slate, phyllite, schist, and gneiss. Non-Foliated Metamorphic Rocks: These rocks don’t have aligned mineral crystals and form as a result of low pressure and temperature. These rocks usually form when parent rock consists of blocky minerals like quartz and calcite. Common non-foliated rocks are marble, quartzite, and hornfels. Metamorphic Rocks Classification Metamorphic rocks are usually classified based on the following properties. - Chemical composition Metamorphic Rocks Uses Metamorphic rocks have different uses. Some rocks are best for the construction industry, home décor, roofing, dimension stone, sculpturing, and as a host for precious gemstones and marbles. The exact use of the rock depends on hardness, quarrying ease, and how easily it can be processed. Levels of Metamorphism The level of metamorphism a rock receives dominates the transformation process and recrystallization. There are two levels of metamorphism that create metamorphic rocks. Low-grade Metamorphism: The temperatures are between 200 to 350°C with relatively low pressure. Low-grade metamorphic rocks are characterized by hydrous minerals. High-Grade Metamorphism: The temperature is above 350°C with higher pressures. These rocks have fewer hydrous minerals because the resultant rock loses H20, and non-hydrous minerals become more common. Types of Metamorphism Contact Metamorphism: It occurs adjacent to igneous intrusions with high temperatures due to superheated magma. The metamorphism process is limited to a small area because only a small area is affected by magma. Contact metamorphism has low pressure because the temperature contrast between the surrounding rock and magma is high at shallow levels in the crust. Regional Metamorphism: It occurs over large areas and is generally not linked with igneous bodies. Regional metamorphism is accompanied by deformation due to non-hydrostatic or differential stress conditions. Regional metamorphism creates strongly foliated rocks like slate, schist, and gneiss. Regional metamorphic rocks are usually found in eroded mountain ranges or the cores of fold/thrust mountain belts. Cataclastic Metamorphism: It happens when two rock bodies slide one another along a fault line. The rocks are created as a result of mechanical deformation. When rocks slide past one another, heat is generated, mechanically deforming the rock. Cataclastic metamorphism is uncommon and happens in narrow zones where shearing has occurred. Hydrothermal Metamorphism: This type of metamorphism happens when hydrothermal fluids with high temperatures and pressure pass through already deposited rocks. It usually happens in basaltic rocks that don’t have hydrous minerals. Hydrothermal metamorphism creates ore deposits. Burial Metamorphism: Burial metamorphism creates metamorphic rocks from sedimentary rocks buried several kilometers below the earth’s surface. The temperature may go up to 300C. Burial metamorphism is often considered regional metamorphism when temperatures increase. Metasomatism: When fluids alter a preexisting igneous, sedimentary, or metamorphic rock, it is known as metasomatism. The new rock has different compositional and mineralogy.
Summer is upon us and now, more than ever, we’re looking forward to enjoying outdoor activities — particularly water sports! Unfortunately, with water sports, we also see an increase in swimmer’s ear. What is swimmer’s ear? Swimmer’s ear is an infection found in the outer ear canal, the area that extends from the outer ear (pinna) to the eardrum (tympanic membrane). The medical term for swimmer’s ear is otitis externa. Swimmer’s ear occurs when moisture gets trapped in the outer ear space, creating the perfect breeding ground for bacterial growth, which can invade the skin of the ear canal. What causes swimmer’s ear? Not surprisingly, a swimmer’s ear is most often caused by moisture or debris retained in the ear canal from swimming. But showering, bathing or other moist environments can also be the source of retained moisture. Swimmer’s ear should be taken seriously and should be treated to prevent any negative effects it may have on your hearing and to prevent further infection. Other factors can contribute to swimmer’s ear, including: - Exposure to excessive bacteria, often found in hot tubs or polluted water - Excessive cleaning of the ear canal with cotton swabs (or any other tool that can damage the skin) - Cuts or skin conditions in the ear canal (eczema, seborrhea, etc.) that create an opening for bacteria to penetrate the skin - Contact with chemicals such as hair spray or hair dye that migrate into the ear canal What are the symptoms of swimmer’s ear? Mild cases of swimmer’s ear will likely begin with itching and irritation in the ear canal and pain that worsens when you tug on the outer ear (pinna). The ear may feel swollen or blocked. A clear, odorless discharge may be present as well. Advanced cases of swimmer’s ear may involve: - Decreased hearing - Intense pain that spreads to the neck, face, or head - Drainage or discharge that has an odor Swimmer’s ear is not typically considered to be a dangerous condition and can clear up quickly following treatment. However, if untreated, the swimmer’s ear can become extremely painful and potentially dangerous, especially for those who are diabetic or have problems with their immune system, including the elderly. Can swimmer’s ear lead to complications? Left untreated, swimmer’s ear can lead to: - Hearing loss - Recurring ear infections (chronic otitis externa): without treatment, the infection can persist - Bone and cartilage damage: untreated infections can spread to the base of the skull, brain, or cranial nerves (diabetics and the elderly are at higher risk for this sort of complication) What is the treatment for swimmer’s ear? Swimmer’s ear is best treated by a physician. The physician will perform an otoscopic examination to confirm there is no eardrum perforation, which would allow moisture to invade the middle ear space. The physician may be able to easily clean the infected area to relieve irritation and pain. Antibiotic ear drops are necessary to clear the infection and will be prescribed by the physician. For a more advanced infection, oral antibiotics or pain medication may be prescribed as well. If the infection does not improve within 3-4 days, the physician may consider different medications. It is important to keep the infected ear(s) dry during the healing process. Are there ways to help prevent swimmer’s ear? It’s wise to take preventative measures to protect your ears and stay in the swim of things this summer. Some recommendations to avoid swimmer’s ear include: - Dry the ears following water exposure, especially swimming. Tip your head to one side to let the water drain out, then repeat on the other side. Never use cotton swabs to dry the ear! A dry towel or tissue can be used as well. - Keep water out of the ear. This may be accomplished by using a barrier such as earplugs. These can be found as over-the-counter products but are most effective when custom molded by a hearing professional for the patients’ ears. - Maintain proper earwax hygiene. Earwax or cerumen plays an important role in protecting the outer ear canal. Too much or too little cerumen can be an issue. Improper ear cleaning methods such as cotton swabs or ear candling can lead to ear canal damage that can lead to infection. - Maintain proper skin health. The skin in the ear canal plays a big role in the prevention of swimmer’s ear. Dry, cracked skin (often the result of health conditions) can be an open invitation to infection. - Protect your ears from chemicals. Keep chemicals from hair spray and dye out of the ear canal with cotton balls or earplugs. - Consider ear drops. There are over-the-counter ear drops designed to help prevent swimmer’s ear. It is important that you DO NOT put anything in your ear canal if there is any risk of you having a perforation of the eardrum. Seeing a physician verify the integrity of the eardrum is strongly advised. It’s important to be aware of swimmer's ear and be on the lookout for symptoms. Schedule an appointment today for a hearing consultation.
In the middle of the nineteenth century, miners discovered hundreds of artifacts made from stone and human remains in their tunnels at Table Mountain and in other areas of the gold mining area. Experts believe that these bones and artifacts were found in Eocene-eга strata (38 to 55 million years). These data were гeⱱeаɩed by Dr. J. D. Whitney of California, the top-ranking government geologist. The book, The Auriferous Gravels of the Sierra Nevada of California was published by Harvard University’s Peabody Museum of Comparative Zoology, in 1880. It was removed from scientific discourse because it сһаɩɩeпɡed Darwinist views of human origins. In 1849, gold was found in the gravels of the Sierra Nevada Mountains’ riverbeds. This discovery attracted a lot of adventurers to towns such as Brandy City, Last Chance and ɩoѕt саmр. Initially, one miner panned the gravels which had made their way into streambeds to make nuggets and flakes. Gold-mining corporations quickly added more resources. They bored shafts into mountainsides and followed the gravel deposits wherever they lead, while others used high ргeѕѕᴜгe water jets to clean the auriferous (gold Ьeагіпɡ) gravels from slopes. Miners found hundreds of stone artifacts as well as human foѕѕіɩѕ. J. D. Whitney presented the most important items to scientists. The age of surface deposits and hydraulic mining artifacts was questionable, but objects found in deeр mine shafts or tunnels can be dated more accurately. J. D. Whitney stated that the geological data indicated that the auriferous rocks were at most Pliocene age. Current geologists believe that some gravel deposits are from the Eocene. Many shafts were driven in Tuolumne County, through Table Mountain’s deeр strata, and then reached the gold-Ьeагіпɡ rocks. Some cases had shafts that extended hundreds of yards horizontally under the latite. The age of the gravels directly above the bedrock may range from 33.2 to 56 million years, while other gravels can range from 9 to 55million years. “If Professor Whitney had fully appreciated the story of human evolution as it is understood today, he would have hesitated to announce the conclusions formulated, notwithstanding the imposing array of testimony with which he was confronted,” said William B. Holmes, a physical anthropologist at the Smithsonian Institution. Or, to put it another way: if facts don’t support an idea, they must be гejeсted. This is exactly what һаррeпed. Whitney still displays some of the objects at the University of California Berkeley’s Phoebe Hearst Museum of Anthropology. Darwinism and other Isms also had an іmрасt on the treatment of archaeological eⱱіdeпсe at Hueyatlaco in Mexico. Cynthia Irwin Williams led archaeologists who discovered stone tools in connection with bones from animal slaughtered during exсаⱱаtіoпѕ at Hueyatlaco in the 1970s. A team of geologists including Virginia Steen McIntyre dated the site. The site was dated using four methods by the geologists: zircon fission tracks dating on volcanic layers above artifact layers, uranium series dates on butchered bones, zircon tгасk dating on volcanic layer above artifact layers and tephra-hydration dating volcanic crystals in volcanic layers above artifacts layers. The archaeologists гeѕіѕted acknowledging the site’s ages because they believed that: (1) No human being was capable of producing such artifacts anywhere on the planet 250,000 years before, and (2) North America was not inhabited until approximately 15,000 to 20,000 years ago.
Building a sustainable future can feel like a massive task. And that’s because the devil is in the details regarding sustainability. It’s a fact that being green supports children’s development. Recycling, gardening, upcycling materials and reducing waste all help support fine motor skills and nurture a sense of responsibility for Mother Nature. Many parents want to save money and the planet. With a little effort, there are many ways to do both. For example, using reusable nappies and DIY baby wipes will help reduce the use of disposable plastic. Growing organic food will cut carbon dioxide emissions from transportation. Sourcing fair-trade, ethical and recycled products will also cut waste. Choosing sustainable building materials, low-VOC paints, and non-toxic glues can cut harmful chemicals from the home environment. Whether they were eco-conscious before kids or not, most people find that becoming a parent makes them more concerned about environmental issues. This is because having children shifts focus to thinking about the legacy they will leave (e.g., environmental). The transition to parenthood also changes people’s consumption and spending habits, which may directly impact natural resources. For example, studies suggest that people with children increase their purchases of environmentally friendly goods such as reusable nappies. This might put more pressure on natural resources, particularly water. Help Your Child Grow In addition to being good for the planet, eco-friendly practices are also good for your baby. Many green nursery products limit the toxic chemicals used, making them safer for babies who are likely to put their hands (and mouths!) on everything they see. An Eco-Healthy Child Care Certified uses only materials with top safety ratings and low emission levels of pollutants. Eco-friendly nurseries are helping to educate the next generation about the importance of sustainability in childcare. The children they teach will take these habits home and influence their own families too, which can have a massive impact on the future of our planet. Environmentally responsible actions such as reducing energy usage, cutting down on paper and plastic, growing food locally and even donating excess produce can help to tackle big issues like climate change and reduced bio-diversity. But sustainable childcare goes beyond that – it’s about helping to invest in people and communities, too. Help the Environment We hear a lot about “reduce, reuse, recycle,” but there are other ways to care for the environment that you don’t always hear about. Purchasing products that are ethically sourced and eco-friendly helps to reduce the amount of plastic and waste on our planet. Choosing green childcare is important and can help your child better understand sustainability and how it benefits our world. It also allows your child to learn new skills that will benefit them throughout their life and help them make informed decisions about how they can help the environment in their way. Studies have shown that having children is associated with increased consideration of environmental protection, particularly when the decision is motivated by concern for the well-being of future generations. Thinking about the future may help to bridge the psychological distance between people and the natural environment. Help Your Child Learn In addition to juggling work, home and family life, new parents have an additional responsibility to teach their children. Luckily, eco-friendly childcare services are equipped to help children learn in ways that promote environmental sustainability. Many eco-friendly schools and centers provide hands-on lessons that teach children the importance of reducing, reusing and recycling. They also introduce concepts that build brainpower, like the life cycle of flora and fauna, natural and weather systems, pollution and more. Other teaching methods that promote sustainable behaviors include piquing children’s interest in topics with storybooks and encouraging them to participate in home activities, such as upcycling waste for craft projects or gardening on-site. Similarly, enabling them to be mindful of the environment on the go, such as when they notice full rubbish bins or dripping taps, is a great way to encourage them to act sustainably. Ultimately, helping children develop a positive attitude towards learning is key to making them responsible citizens of the world.
\|Disaster Mitigation - 2nd Edition (Department of Humanitarian Affairs/United Nations Disaster Relief Office - Disaster Management Training Programme - United Nations Development Programme , 1994, 64 p.)\| \|Part 1 - Introduction to mitigation concepts\| The worst effects of any disaster are the deaths and injuries caused. The scale of disasters and the number of people they kill are the primary justifications for mitigation. Understanding the way that people are killed and injured in disasters is a prerequisite for reducing casualties. Among the sudden onset disasters, floods and earthquakes cause the most casualties worldwide, with storms and high winds being less deadly but far more widespread. In earthquakes over 75% of fatalities are caused by building collapse. In floods deaths occur by drowning, mainly outdoors and in fast flowing currents or in turbulent water. Saving lives in earthquakes means focussing on prevention of building collapse. Reducing fatalities from floods means limiting the exposure of people to rapid inundation - either by keeping people out of the track of potential water flows or by preventing the flows from occurring. The consequences of physical damage are often more important than the damage itself. The consequences of physical damage are often more important than the damage itself. A damaged factory can no longer continue to manufacture. The company may not survive the loss. The people it employs may lose their jobs. The jobless have no income to spend in their local shops and the whole local economy suffers. Damage to infrastructure and to the means of production depresses the economy. Mitigation also entails the protection of the economy from disasters. Economic activity in the more industrialized societies is complex and interdependent, with service industries dependent on manufacturing, which in turn relies on supplies of raw materials, labor, power and communications. This complex interdependency is extremely vulnerable to disruption by hazards affecting any one link in the chain. Newly industrializing societies are most vulnerable of all. Agricultural sectors of the economy are most vulnerable to drought but also to floods and high winds, disease and pest attack and pollution. Industry is more vulnerable to earthquake damage and the disruption of transportation and utilities networks. Commerce and finance are most vulnerable to disruption of production, population migration and to breakdowns in communications systems. Mitigation measures that focus on protecting the most vulnerable elements and activities - the weakest links - in the different sectors of the economy will help protect the achievements of economic development.
- Jewish and Christian tradition ascribes Lamentations to Jeremiah. It is written in the style of the book of Jeremiah by Baruch. - Lamentations describes the divine judgment on Jerusalem in 586 BC. Jeremiah and Baruch were eye-witnesses of this event. - The book was written after 586 BC and before 575 BC. - It is a poetic book consisting entirely of laments. Ancient literature has a tradition of laments over the destruction of cities. - It is read on Jewish festival days commemorating the destruction of the two temples. - Genre: Poetic metaphor - This book belonging to the Apocrypha is written in Jeremiah’s style by Baruch son of Neriah, Jeremiah’s secretary. - It was written in the 5th year of the destruction of Jerusalem when Baruch had joined the exiles. - Baruch read this book to the exiles living in Babylon near the River Sudi. - It is a prayer, a lament and a warning to do what is right. - Chapter 6 is a copy of a letter sent by Jeremiah to the captives in Babylon. - It is apparent that after 586 BC Baruch has ended up as an exile in Babylon, while Jeremiah became an exile in Egypt where he was martyred. Apart from writing Lamentations and the book entitled Baruch, Jeremiah’s scribe also wrote down the prophecies of Jeremiah and the four history of Israel books I Samuel, 2 Samuel, 1 Kings and 2 Kings. Thus, Baruch wrote six books of the Bible and one book of the Apocrypha.
Estimated time to complete Module 1: 60 minutes Before we begin on this journey of introducing PBL to our classrooms, it is important to understand what Project-Based Learning is and what it is not. The selections in this Module will provide background about the definition of Project-Based Learning, its purpose and intent, its advantages, and its uses. What is the difference between Project-Based Learning and Project-Oriented Learning? How might PBL transform our classrooms into more student-centered ones and allow students to go deeper into their learning and understanding about a topic? As you progress through the Module, reflect on the following guiding questions: - What is important for my students to know and be able to do when they leave my classroom? - Does my classroom provide an opportunity for students to: - relate what they learn to their lives? - make content relevant and meaningful to the lives they will lead? - prepare students for the lives they will lead?
Viking ships were marine vessels of unique structure, used in Scandinavia from the Viking Age throughout the Middle Ages. The boat-types were quite varied, depending on what the ship was intended for, but they were generally characterized as being slender and flexible boats, with symmetrical ends with true keel. They were clinker built, which is the overlapping of planks riveted together. Some might have had a dragon's head or other circular object protruding from the bow and stern for design, although this is only inferred from historical sources. Viking ships were used both for military purposes and for long-distance trade, exploration and colonization. In the literature, Viking ships are usually seen divided into two broad categories: merchant ships and warships, the latter resembling narrow "war canoes" with less load capacity, but higher speed. However, these categories are overlapping; some transport ships would also form part of war fleets. As a rule, ship lanes in Scandinavia followed coastal waters, hence a majority of vessels were of a lighter design, while a few types, such as the knarr, could navigate the open ocean. The Viking ships ranged from the Baltic Sea to far from the Scandinavian homelands, to Iceland, the Faroe Islands, Greenland, Newfoundland, the Mediterranean, the Black Sea and Africa. One particular advantage of the Viking ship is the comparatively low weight, making land transport and portage routine, as in crossing Jutland instead of rounding Skagen to enter or exit the Baltic Sea, and travel on the river networks of Eastern Europe. The ship has been functioning as the centerpiece of Scandinavian culture for millennia, serving both pragmatic and religious purposes, and its importance was already deeply rooted in the Scandinavian culture when the Viking Age began. Scandinavia is a region with relatively high inland mountain ranges, dense forests and easy access to the sea with many natural ports. Consequently, trade routes were primarily operated via shipping, as inland travel was both more hazardous and cumbersome. Many stone engravings from the Nordic Stone Age and in particular the Nordic Bronze Age, depict ships in various situations and valuable ships were sacrificed as part of ceremonial votive offerings since at least the Nordic Iron Age, as evidenced by the Hjortspring and Nydam boats. The Viking Age saw the first local developments of trading ports into forts and coastal towns, all of which were deeply dependent on the North Sea and the Baltic Sea for survival and growth. Control of the waterways was of great economical and political importance, and consequently, ships were in high demand. Because of their overwhelming importance, ships became a mainstay of the Viking religion, as they evolved into symbols of power and prowess. The Hedeby coins, among the earliest known Danish currency, have impressions of ships as emblems, showing the importance of naval vessels in the area. Through such cultural and practical significance, the Viking ship progressed into the most powerful, advanced naval vessel in Viking Age Europe. Knarr is the Norse term for ships that were built for cargo transport. A length of about 54 feet (16 m) and a beam of 15 feet (4.6 m) are not untypical, and the hull could be capable of carrying up to 24 tons. Overall displacement: 50 tons. This is shorter than the Gokstad type of longships, but knarrs are sturdier by design and they depended mostly on sail-power, only putting oars to use as auxiliaries if there was no wind on the open water. Because of this, the knarr was used for longer voyages, ocean-going transports and more hazardous trips than the Gokstad type. It was capable of sailing 75 miles (121 km) in one day, and held a crew of about 20–30. Knarrs routinely crossed the North Atlantic in the Viking Age, carrying livestock and goods to and from Greenland and the North Atlantic islands. The design of the knarr later influenced the design of the cog, used in the Baltic Sea by the Hanseatic League. Examples of Viking Age knarr are Skuldelev 1, which was excavated in Denmark in 1962 and is believed to be from about 1030 AD, and the Äskekärr ship, which was found in Sweden in 1933 and is believed to be from about 930 AD. Longships were naval vessels made and used by the Vikings from Scandinavia and Iceland for trade, commerce, exploration, and warfare during the Viking Age. The longship's design evolved over many years, as seen in the Nydam and Kvalsund ships. The character and appearance of these ships have been reflected in Scandinavian boatbuilding traditions until today. The average speed of Viking ships varied from ship to ship but lay in the range of 5 to 10 knots (9 to 19 km/h), and the maximum speed of a longship under favorable conditions was around 15 knots (28 km/h). The long-ship is as a graceful, long, narrow, light, wooden boat with a shallow draft hull designed for speed. The ship's shallow draft allowed navigation in waters only one meter deep and permitted beach landings, while its light weight enabled it to be carried over portages. Longships were also double-ended, the symmetrical bow and stern allowing the ship to reverse direction quickly without having to turn around. Longships were fitted with oars along almost the entire length of the boat itself. Later versions sported a rectangular sail on a single mast which was used to replace or augment the effort of the rowers, particularly during long journeys. Longships can be classified into a number of different types, depending on size, construction details, and prestige. The most common way to classify longships is by the number of rowing positions on board. Types ranged from the Karvi, with 13 rowing benches, to the Busse, one of which has been found with an estimated 34 rowing positions. Longships were the epitome of Scandinavian naval power at the time and were highly valued possessions. They were owned by coastal farmers and assembled by the king to form the leidang in times of conflict, in order to have a powerful naval force at his disposal. While longships were deployed by the Norse in warfare, there are no descriptions of naval tactics such as ramming, etc. Instead, the ships would sometimes be lashed together in battle to form a steady platform for infantry warfare. Longships were called dragonships (drakuskippan) by the Franks because they had a dragon-shaped prow. The Karve was a small type of Viking longship, with a broad hull somewhat similar to the knarr. They were used for both war and ordinary transport, carrying people, cargo or livestock. Because they were able to navigate in very shallow water, they were also used for coasting. Karves typically had broad beams of approximately 17 feet (5.2 m). Viking ships varied from other contemporary ships, being generally more seaworthy and lighter. This was achieved through use of clinker (lapstrake) construction. The planks on Viking vessels were rived (split) from large, old-growth trees — especially oak. A ship's hull could be as thin as one inch (2.5 cm), as a rived plank is stronger than a sawed plank found in later craft, resulting in a strong yet supple hull. Working up from a stout oaken keel and ribs, the shipwrights would rivet on the planks using wrought iron rivets and roves, reinforced with added support ribs and thwarts. Each tier of planks overlapped the one below, and a caulking of tarred cow's hair was used between planks to create a waterproof hull. Remarkably large vessels could be constructed using traditional clinker construction. Dragon-ships carrying 100 warriors were not uncommon. Furthermore, during the early Viking Age, oar ports replaced rowlocks, allowing oars to be stored while the ship was at sail and to provide better angles for rowing. The largest ships of the era could travel five to six knots using oar power and up to ten knots under sail. With such technological improvements, the Vikings began to make more and more ocean voyages, as their ships were more seaworthy. However, in order to sail in ocean waters, the Vikings needed to develop methods of relatively precise navigation. Most commonly, a ship's pilot drew on traditional knowledge to set the ship's course. Essentially, the Vikings simply used prior familiarity with tides, sailing times, and landmarks in order to route courses. For example, scholars contend that the sighting of a whale allowed the Vikings to determine the direction of a ship. Because whales feed in highly nutritious waters, commonly found in regions where landmasses have pushed deep-water currents towards shallower areas, the sighting of a whale functioned as a signal that land was near. On the other hand, some academics have proposed that the Vikings also developed more advanced aids to navigation, such as the use of a sun compass. A wooden half-disc found on the shores of Narsarsuaq, Greenland initially seemed to support this hypothesis. However, further investigation of the object revealed that the slits inscribed in the disc are disproportionately spaced, and so the object could not in fact function as an accurate compass. Rather it has been suggested that the instrument is instead a “confession disc” used by priests to count the number of confessions in their parish. Similarly, researchers and historians continually debate the use of the sunstone in Viking navigation. Because a sunstone is able to polarize light, it is a plausible method for determining direction. By showing which direction light waves are oscillating, the sunstone has the potential to show the sun's position even when the sun is obscured by clouds. The stone changes to a certain color, based on the direction of the waves, but only when the object is held in an area with direct sunlight. Thus, most scholars debate the reliability and the plausibility of using a navigational tool that can only determine direction in such limited conditions. Viking sagas routinely tell of voyages where Vikings suffered from being "hafvilla" (bewildered)—voyages beset by fog or bad weather, where they completely lost their sense of direction. This description suggests they did not use a sunstone when the sun was obscured. Moreover, the fact that this same bewilderment could arise when the winds died suggests that the Vikings relied on prevailing winds to navigate, as expected if their skills depended principally on traditional knowledge. Prominent men or women in Norse society sometimes received a ship burial. The body of the deceased would be prepared and dressed in fine clothes and then be transported to the burial-place in a wagon drawn by horses. The deceased would be placed on the ship, along with many prized possessions. Horses, dogs and occasionally thralls and households might also be sacrificially killed and buried with the deceased. The origin and meaning of these customs remain unknown. Several examples of Viking ship burials have been excavated, e.g. the Oseberg ship in Norway, containing the remains of two women, the Gokstad ship in Norway, and the Ladby ship in Denmark. There are literary sources such as the Norse Skjoldunga Saga and the Ynglinga Saga which describe more literal "ship burials" in which the deceased and goods are placed on a boat in the water and the vessel is launched into the sea, sometimes being shot with burning arrows and vanishing into the night, ablaze. Nothcotte Toller, however, states: Whether such fiery funerals ever actually took place is impossible to know; but it is much more difficult to imagine that a king's body and accompanying treasures would have been simply pushed out to sea, where they would have been in danger of returning, or of falling into the hands of strangers or even enemies who might maltreat the one and plunder the other. Burial of ships is an ancient tradition in Scandinavia, stretching back to at least the Nordic Iron Age, as evidenced by the Hjortspring boat (400–300 BC) or the Nydam boats (200–450 AD), for example. Ships and bodies of water have held major spiritual importance in the Norse cultures since at least the Nordic Bronze Age. Several original Viking ships have been found through the ages, but only a few have been relatively intact. The most notable of these few ships include: - Gokstad ship: overall length – approximately 23.3 m (76 ft) - Oseberg ship: overall length – approximately 21.5 m (71 ft) - Skuldelev ships: five ships found at the same location, from about 11.2 to 30 m (37 to 98 ft) long - Tune ship: may have been up to 18.7 m (61 ft) long Examples of other Viking ships, including some that are relatively well-preserved and some where only very small parts remain: - Äskekärr ship - Gjellestad ship burial: about 23–24 m (75–79 ft) long (excavation ongoing as of June 2020) - Hedeby 1: estimated about 26–32 m (85–105 ft) long - Kvalsund ship - Ladby ship - Myklebust Ship - Roskilde 6: found during the expansion of the Viking Ship Museum and the longest known Viking ship at about 37 m (121 ft) Have been regarded as Viking ships, but from before or after the Viking Age: - Salme ships: from 700 to 750 AD, before the Viking Age - Lapuri ship: from 1250 to 1300 AD, after the Viking Age Viking ship replicas are one of the more common types of ship replica. Viking, the very first Viking ship replica, was built by the Rødsverven shipyard in Sandefjord, Norway. In 1893 it sailed across the Atlantic Ocean to Chicago for the World's Columbian Exposition. There are a considerable number of modern reconstructions of Viking Age ships in service around Northern Europe and North America. The Viking Ship Museum in Roskilde, Denmark, has been particularly prolific in building accurate reconstructions of archaeological finds in its collection. - "Eldar Heide (2014). The early Viking Ship types (Sjøfartshistorisk årbok 2050. 81–153.)" (PDF). Archived from the original (PDF) on 23 November 2015. Retrieved 24 May 2020. - Jones, Gwyn, A history of the Vikings (Oxford 2001). - Were also seen in the Egypt Red Sea - Peter Sawyer, (1975) The Oxford Illustrated History of the Vikings. Oxford University Press ISBN 978-0-19-285434-6 ISBN 0-19-285434-8 - Plural of knarr is knerrir. - "Discovered: A Viking Ship!" (PDF). www.lodose.eu. Archived from the original (PDF) on 11 October 2019. Retrieved 24 May 2020. - "Fejl: Siden blev ikke fundet / adgang er ikke tilladt". Vikingeskibsmuseet Roskilde. Archived from the original on 18 July 2011. Retrieved 6 April 2011. - Ervan G. Garrison (1998). History of Engineering and Technology: Artful Methods. CRC Press. p. 111. ISBN 978-0-8493-9810-0. Archived from the original on 2 May 2023. Retrieved 14 May 2018. - Lapstrake hull schematic Archived 17 July 2012 at the Wayback Machine - Stephen Batchelor (30 April 2010). Medieval History For Dummies. John Wiley & Sons. p. 101. ISBN 978-0-470-66460-5. - Richard Hall, The World of the Vikings (New York, 2007), 55. - Hall, The World of the Vikings, 54. - Oscar Noel and Sue Ann Bowling (21 March 1988). "Polar Navigation and the Sky Compass: Article #865". Alaska Science Forum. Archived from the original on 27 April 2012. Retrieved 24 November 2010. - Hafvilla: A Note on Norse Navigation, G. J. Marcus, Speculum, Vol. 30, No. 4 (Oct. 1955), pp. 601–05, Published by: Medieval Academy of America, https://www.jstor.org/stable/2849616 Archived 30 January 2020 at the Wayback Machine (accessed 2 November 2011). - Thomas Nothcotte Toller (2003). Textual and Material Culture in Anglo-Saxon England. D.S. Brewer. p. 43. - Recreating a Viking voyage – BBC - The Viking ship Museum in Roskilde, Denmark - Web page about the Gokstad ship excavation - The Oslo Viking Ship Museum - Gaia, the Gokstad Ship copy - Munin, a Gokstad replica in Vancouver, BC - Comparison between Viking and Egyptian Ships - Dreknor Project, Normandy - Leif Ericson Viking Ship - Rebuilding and sailing a Viking Knarr ship - History of vikings - Francis Miltoun: Ships & shipping, London, Alexander Moring Ltd., 1903 - The Mariner's Museum: Age of exploration - New Oseberg Ship Foundation - Video: Viking ship replica Saga Oseberg tacking - Video: Viking ship replica Saga Oseberg wearing - Video: Viking ship replica Saga Oseberg sailing close hauled
SARS (Severe Acute Respiratory Syndrome) is an acute respiratory disease. The causative agent of SARS is a previously unknown species of the coronavirus. Sequencing of the SARS virus has shown that it differs from the previously known groups of coronaviruses in nucleotide sequence by 50-60%. The results of sequencing the virus conducted by the Chinese scientists differ significantly from those obtained by Canadian and American researchers, suggesting that the virus possesses an ability to mutate rapidly. Coronavirus is rather unstable, being immediately killed by heating it to 56°C, or under the influence of disinfectants. However, there is evidence of higher stability of the SARS virus. On the plastic surface, the virus may persist for up to 2 days while, in sewage waters, up to 4 days. However, within this period, the number of viral particles is constantly falling. It is possible to suggest that the SARS virus appeared as the result of mutations of the previously known coronavirus species. Get a price quote The disease is transmitted via airborne droplets and dust. In order for a virus to enter the body, one must be at a distance of not more than 10 cm from its source. In addition, the virus can live outside the body for some time, so contamination through the belongings of the patient, as well as objects, which he/she used, is also possible (Ahuja and Ooi 11). The SARS Virus Effect on the Body SARS has an incubation period of 2-5 days and, according to some estimates, up to 10-14 days (Ahuja and Ooi 10). The main symptom of SARS is profuse serous rhinitis. Body temperature is normal or low-grade. The duration of the disease is up to 7 days. The first symptoms of SARS are chills, headache, muscle pain, weakness, dizziness, and fever up to 38°C and above. This febrile phase lasts for 3-7 days (Ahuja and Ooi 9). The respiratory symptoms of atypical pneumonia, such as sore throat are not typical. Most patients have a mild form of the disease, and they recover within 1-2 weeks. Other patients develop acute respiratory distress within a week, which includes dyspnea and hypoxemia (Ahuja and Ooi 9). In addition to the above symptoms, there also can be a cough, runny nose, and the point mucosal hyperemia of the posterior pharyngeal wall. Nausea, vomiting, and abdominal pain are also possible. After 3-7 days, the disease enters the respiratory phase, which is characterized by repeated fever periods, the appearance of persistent nonproductive cough, and difficulty breathing. The examination reveals pallor, cyanosis of the lips and nail plates, tachycardia, muted tones of the heart, and a tendency to hypotension. In 80-90% of cases, the condition improves within a week, symptoms of respiratory failure regress, and recovery occurs. In 10-20% of cases, the condition progressively worsens and symptoms similar to acute respiratory distress syndrome are developed. Death occurs as a result of respiratory failure (Ahuja and Ooi 9). New to BestWritingHelp? Get your 15% OFF the first order! Code firstorder The disease was first reported in November 2002 in Guangdong Province, China (Brookes 12). Measures to prevent the spread of the epidemic were not accepted immediately as the Chinese government at first tried to hide the outbreak of this disease in the country. However, the epidemic quickly spread to neighboring Hong Kong and Vietnam, in late February 2003, and later on to other countries and continents. The first recorded case of SARS was reported in Hanoi on February 26, 2003 (Brookes 47). The severity of symptoms, high mortality, and the possibility of infection of the hospital staff caused great anxiety of the world community, and on March 12, 2003, the World Health Organization (WHO) issued a global alert about the need to stop the spread of this disease. Tourists were advised not to travel to Southern China. According to WHO, during the epidemic, 8436 cases of SARS and more than 900 deaths were registered in 30 countries, with the largest number of victims reported in Mainland China (348 cases) and Hong Kong (298 cases). Casualties also took place in Singapore, Canada, Taiwan, Vietnam, Malaysia, Thailand, and the Philippines (World Health Organization n.p.). To buy academic assignment from our writing service is the best option for you if: You have problemswith academic performance and your marks are not good You are unable to cope with writingthe academic assignment Reputation and the feeling of self-esteem are importantfor you You cannot copewith the assignment due to the hectic schedule The source of the outbreak was unknown until recently, and the idea of animals being a source of the disease was considered irrelevant. However, the latest researches showed that animals, particularly bats, were the carriers of the disease. According to researchers from the U.S., Australia, and China, viruses similar to the SARS coronavirus were previously detected in the area of bats living in China, Europe, and Africa; earlier, however, bats were not considered a direct precursor of the virus due to lack of evidence. However, the latest results provide strong evidence that these mammals are the source of the SARS coronavirus. Peter Daszak of EcoHealth Alliance, New York, and his colleagues tracked the colony of Chinese red horseshoe bats (Rhinolophus sinicus) in the Yunnan Province during the 12-month period and found two coronaviruses, which were close relatives of the SARS coronavirus as they were tropic to the same receptor (ACE2) in the human body (EcoHealth Alliance n.p.). In recent years, molecular biologists have found evidence that the SARS virus may be associated with coronaviruses that live in the body of bats, but some scientists have doubted this assertion. Group of Daszak could dispel these doubts by finding a special strain of the “bat” coronavirus SL-CoV-WIV1 in feces of one of the residents of the caves in Southern China. According to scientists, the genome of the virus is similar to that of the SARS virus by 99% and this pathogen is able to infect human and bat cells using the same mechanisms as the causative agent of SARS. Furthermore, human antibodies to the SARS virus are successfully able to neutralize the “bat” coronavirus, which means close kinship between these pathogens (EcoHealth Alliance n.p.). Struggling with your essay? Ask professionals to help you? WHO has developed the basic principles of the infection prevention: the prohibition to visit regions adverse against the infection; strict anti-epidemic control over individuals returning from regions adverse against the infection, the use of a single application of individual masks in case of a need to contact with people suspicious for the development of infection. Through the use of restrictive measures and the establishment of the protective regime, the international community achieved the first victory over SARS. In 2003, the World Health Organization officially declared the end of the SARS epidemic (Brookes 223).
Once students have investigated the driving question, they will move into the Calibration Stage. This is comprised of: The Check In Ensuring that students have an adequate grasp of the driving-question and what the main issue is behind it prior to proceeding to generating ideas and solutions. While you should have many informal and formative check-ins with students throughout your unit, having a more formal process to ensure that students have the proper understanding of the driving question and what they are solving for is essential. This is especially true when students are working with a driving question that is open-ended and could lead in a variety of directions. Taking time for the Calibration Stage will allow you to help students make course corrections before they head somewhere that you do not want them to. How Might We... After students have completed the Investigation Stage, in small groups have them complete the following statement in a couple of different ways based upon what they found out about the driving question: “How might we _________________________ for ___________________________?” For example, if students were investigating the driving question “How can we improve our local beach?” different ways to complete this phrase could include: “How might we design a new board walk for young families to use?” or “How might we include a more effective way to dispose of trash and recyclables for people who BBQ at the beach?” Based upon what they discovered about the driving question in the Investigation Stage, have students brainstorm all of the different ways that they can re-phrase or re-structure the driving question. For example, if students were investigating the driving question “How can we design a winning sundae for the ice cream store we are working with?” possible ways that this question could be rephrased include: “How can we design a sundae that is both sweet and salty for our ice cream store?” “How can we design a sundae that looks mouthwateringly delicious?” “How can we create a great sundae that does not cost a lot?”
The food children eat affects their long term oral health. Some foods have nutrients teeth need. Others are full of acids and sugars that are harmful to teeth. With so many unhealthy food choices being marketed to children every day, it is vital that you take a stand. Offer fun, healthy snacks and model the better food choices you want your kids to make. Offer healthy snack choices. Kids should have a well-balanced and nutritional diet. This not only promotes overall health but also helps build a strong healthy smile. Nutrition is an important part of oral health. Teaching your kids about eating healthy and limiting sugary foods will help foster a balanced diet from an early age. This will form habits that will result in a lifetime of strong teeth and better overall health. Have fun with snacks. Promote a nutritious diet by getting creative with snack choices. If you show your kids that healthy snacks are fun, they will be more likely to eat them. Apple slices with peanut butter, fruit smoothies, and yogurt with granola or fruit are great examples of fun, yet healthy combinations. Remember to avoid soda and sugary drinks. These can leave sugars on teeth and can increase the risk of plaque and tooth decay. Water is always the best solution! Eating a well-balanced lunch and dinner is important as well. Make sure to add a variety of fruits and vegetables to every meal so that your kids become accustomed to them. Be a good role model. Children learn habits by following the example set by their parents. Send your kids the right message by eating plenty of fruits and vegetables yourself. Avoid sugary snacks that can cause cavities or gum disease. Be sure to practice good oral hygiene in front of your kids. If you brush and floss after meals and snacks, your kids will follow the example. Consider brushing together with your child to reinforce good brushing skills and habits. Make sure to brush at least twice a day, after breakfast and before bedtime. If it is possible, try to encourage your child to brush after lunch or after sweet snacks. Follow up. Don’t forget it is also very important to have regular dental appointments for your child, and model healthy habits by seeing your own dentist regularly. If you have any further questions, feel free to contact us for more ideas on how to promote healthy snacking for great long term dental health!
Good special education services are intensive and expensive. Resources are limited. If you have a child with special needs, you may wind up battling the school district for the services your child needs. To prevail, you need information, skills, and tools. Who can be an advocate? Anyone can advocate for another person. Here is how the dictionary defines the term “advocate”: ad-vo-cate — Verb, transitive. To speak, plead or argue in favor of.Synonym is support. - One that argues for a cause; a supporter or defender; an advocate of civil rights. - One that pleads in another’s behalf; an intercessor; advocates for abused children and spouses. - A lawyer. (The American Heritage Dictionary of the English Language, Third Edition) An advocate performs several functions: - Supports, helps, assists, and aids - Speaks and pleads on behalf of others - Defends and argues for people or causes Different types of advocates Special education advocates work to improve the lives of children with disabilities and their families. You are likely to meet different types of advocates. Lay advocates use specialized knowledge and expertise to help parents resolve problems with schools. When lay advocates attend meetings, write letters, and negotiate for services, they are acting on the child’s behalf. Most lay advocates are knowledgeable about legal rights and responsibilities. In some states, lay advocates represent parents in special education due process hearings. Educational advocates evaluate children with disabilities and make recommendations about services, supports and special education programs. When educational advocates go to eligibility and IEP meetings, they are acting on the child’s behalf. Some educational advocates negotiate for services. Others are less knowledgeable about special education law and how to use tactics and strategies. Teachers and special education providers often see themselves as advocates. Teachers, administrators, and school staff often provide support to children and their families. But because they are employed by school districts, school personnel are limited in their ability to advocate for children with disabilities without endangering their jobs. Parents are natural advocates for their children. Who is your child’s first teacher? You are. Who is your child’s most important role model? You are. Who is responsible for your child’s welfare? You are. Who has your child’s best interests at heart? You do. You know your child better than anyone else. The school is involved with your child for a few years. You are involved with your child for life. You should play an active role in planning your child’s education. The law gives you the power to make educational decisions for your child. Do not be afraid to use your power. Use it wisely. A good education is the most important gift you can give to your child. As the parent of a child with a disability, you have two goals: To ensure that the school provides your child with a “free appropriate public education” that includes “specially designed instruction … to meet the [child’s] unique needs…” (20 U.S.C. $1401)To build a healthy working relationship with the school. What advocates do Advocacy is not a mysterious process. Here is a quick overview of advocacy skills. Advocates gather facts and information. As they gather information and organize documents, they learn about the child’s disability and educational history. Advocates use facts and independent documentation to resolve disagreements and disputes with the school. Learn the Rules of the Game Advocates educate themselves about their local school district. They know how decisions are made and by whom. Advocates know about legal rights. They know that a child with a disability is entitled to an “appropriate” education, not the “best” education, nor an education that “maximizes the child’s potential.” They understand that “best” is a four-letter word that cannot be used by parents or advocates. Advocates know the procedures that parents must follow to protect their rights and the child’s rights. Plan and Prepare Advocates know that planning prevents problems. Advocates do not expect school personnel to tell them about rights and responsibilities. Advocates read special education laws, regulations, and cases to get answers to their questions. Advocates learn how to use test scores to monitor a child’s progress in special education. They prepare for meetings, create agendas, write objectives, and use meeting worksheets and follow-up letters to clarify problems and nail down agreements. Keep Written Records Because documents are often the keys to success, advocates keep written records. They know that if a statement is not written down, it was not said. They make requests in writing write and polite follow-up letters to document events, discussions, and meetings. Ask Questions, Listen to Answers Advocates are not afraid to ask questions. When they ask questions, they listen carefully to answers. Advocates know how to use “Who, What, Why, Where, When, How, and Explain Questions” (5 Ws + H + E) to discover the true reasons for positions. Advocates learn to define and describe problems from all angles. They use their knowledge of interests, fears, and positions to develop strategies. Advocates are problem solvers. They do not waste valuable time and energy looking for people to blame. Advocates know that parents negotiate with schools for special education services. As negotiators, advocates discuss issues and make offers or proposals. They seek “win-win” solutions that will satisfy the interests of parents and schools. Your assignment — plan for the future What are your long-term goals for your child? What do you envision for your child in the future? If you are like most parents, you are focused on the present. You haven’t given much thought to the future. Do you expect your child to be an independent, self-sufficient member of the community? Although some children with disabilities will require assistance as adults, most will grow up to be adults who hold jobs, get married, and live independently. If you have a vision about what you want for your child in the future, you are more likely to achieve your goals. If you believe others will make long-term plans for your child and provide your child with the necessary skills to be an independent, self sufficient member of society, you are likely to be disappointed. What do you want for your child’s What are your goals for your child’s future? Do you have a master plan for your child’s education? If you want your child to grow up to be an independent adult, what does your child need to learn before he or she leaves the public school system? What do you want? Develop a Master Plan If you are like many parents, you don’t have a master plan. You don’t know where you are, where you need to go, or how to get there. Do not expect school personnel to make long-term plans for your child — this is your responsibility. Begin by thinking about your vision for your child’s future. What are your long-term goals for your child? What will your child need to learn? What services and supports will your child need to meet these goals? Are you ready to advocate? Here is a list of supplies that will help you get started: - Two 3-ring notebooks (one for your child’s file; one for information about your child’s disability and educational information) - 3-hole punch - Package of sticky notes - #10 Envelopes - Contact log - Small tape recorder In this article, you learned about lay advocates and educational advocates, and about limitations on teachers and special education staff in their ability to advocate. You learned that parents are natural advocates for their children. You learned about basic advocacy skills — gathering and organizing information, planning and preparing, documenting, problem solving, and negotiating. You have a list of supplies to help you advocate. You learned that you must plan for your child’s future. A plan is like a roadmap. When you have a plan, you know where you are, where you need to go, and how to know when you arrive. The parent's journey from emotions to advocacy On your journey from emotions to advocacy, you will learn about your child’s disability, educational and remedial techniques, educational progress, Individualized Education Programs (IEPs), and how to artfully advocate. You will learn how to present your concerns and problems in writing, prepare for meetings, and search for win-win solutions. You will learn how to use your emotions as a source of energy and power, and how to focus on getting an appropriate education for your child. This article is based on a chapter in Wrightslaw: From Emotions to Advocacy: The Special Education Survival Guide by Pamela Wright and Peter Wright. Click here to learn about more books and products by Pete and Pam Wright.
The Earth's ozone layer protects all life from the sun's harmful radiation, but human activities have damaged this shield. Less protection from ultraviolet light will, over time, lead to higher skin cancer and cataract rates and crop damage. The U.S., in cooperation with over 140 other countries, is phasing out the production of ozone-depleting substances in an effort to safeguard the ozone layer. The Earth's atmosphere is divided into several layers. The lowest region, the troposphere, extends from the Earth's surface up to about 10 kilometers (km) in altitude. Virtually all human activities occur in the troposphere. Mt. Everest, the tallest mountain on the planet, is only about 9 km high. The next layer, the stratosphere, continues from 10 km to about 50 km. Most commercial airline traffic occurs in the lower part of the stratosphere. Most atmospheric ozone is concentrated in a layer in the stratosphere about 15-30 kilometers above the Earth's surface. Ozone is a molecule containing three oxygen atoms. It is blue in color and has a strong odor. Normal oxygen, which we breathe, has two oxygen atoms and is colorless and odorless. Ozone is much less common than normal oxygen. Out of each 10 million air molecules, about 2 million are normal oxygen, but only 3 are ozone. However, even the small amount of ozone plays a key role in the atmosphere. The ozone layer absorbs a portion of the radiation from the sun, preventing it from reaching the planet's surface. Most importantly, it absorbs the portion of ultraviolet light called UVB. UVB has been linked to many harmful effects, including various types of skin cancer, cataracts, and harm to some crops, certain materials, and some forms of marine life. At any given time, ozone molecules are constantly formed and destroyed in the stratosphere. The total amount, however, remains relatively stable. The concentration of the ozone layer can be thought of as a stream's depth at a particular location. Although water is constantly flowing in and out, the depth remains constant. While ozone concentrations vary naturally with sunspots, the seasons, and latitude, these processes are well understood and predictable. Scientists have established records spanning several decades that detail normal ozone levels during these natural cycles. Each natural reduction in ozone levels has been followed by a recovery. Recently, however, convincing scientific evidence has shown that the ozone shield is being depleted well beyond changes due to natural processes. For over 50 years, chlorofluorocarbons (CFCs) were thought of as miracle substances. They are stable, nonflammable, low in toxicity, and inexpensive to produce. Over time, CFCs found uses as refrigerants, solvents, foam blowing agents, and other smaller applications. Other chlorine-containing compounds include methyl chloroform, a solvent, and carbon tetrachloride, an industrial chemical. Halons, extremely effective fire extinguishing agents, and methyl bromide, an effective produce and soil fumigant, contain bromine. All of these compounds have atmospheric lifetimes long enough to allow them to be transported by winds into the stratosphere. Because they release chlorine or bromine when they break down, they damage the protective ozone layer. The discussion of the ozone depletion process below focuses on CFCs, but the basic concepts apply to all of the ozone-depleting substances (ODS). In the early 1970s, researchers began to investigate the effects of various chemicals on the ozone layer, particularly CFCs, which contain chlorine. They also examined the potential impacts of other chlorine sources. Chlorine from swimming pools, industrial plants, sea salt, and volcanoes does not reach the stratosphere. Chlorine compounds from these sources readily combine with water and repeated measurements show that they rain out of the troposphere very quickly. In contrast, CFCs are very stable and do not dissolve in rain. Thus, there are no natural processes that remove the CFCs from the lower atmosphere. Over time, winds drive the CFCs into the stratosphere. The CFCs are so stable that only exposure to strong UV radiation breaks them down. When that happens, the CFC molecule releases atomic chlorine. One chlorine atom can destroy over 100,000 ozone molecules. The net effect is to destroy ozone faster than it is naturally created. To return to the analogy comparing ozone levels to a stream's depth, CFCs act as a siphon, removing water faster than normal and reducing the depth of the stream. Large fires and certain types of marine life produce one stable form of chlorine that does reach the stratosphere. However, numerous experiments have shown that CFCs and other widely-used chemicals produce roughly 85% of the chlorine in the stratosphere, while natural sources contribute only 15%. Large volcanic eruptions can have an indirect effect on ozone levels. Although Mt. Pinatubo's 1991 eruption did not increase stratospheric chlorine concentrations, it did produce large amounts of tiny particles called aerosols (different from consumer products also known as aerosols). These aerosols increase chlorine's effectiveness at destroying ozone. The aerosols only increased depletion because of the presence of CFC- based chlorine. In effect, the aerosols increased the efficiency of the CFC siphon, lowering ozone levels even more than would have otherwise occurred. Unlike long-term ozone depletion, however, this effect is short-lived. The aerosols from Mt. Pinatubo have already disappeared, but satellite, ground-based, and balloon data still show ozone depletion occurring closer to the historic trend. One example of ozone depletion is the annual ozone "hole" over Antarctica that has occurred during the Antarctic Spring since the early 1980s. Rather than being a literal hole through the layer, the ozone hole is a large area of the stratosphere with extremely low amounts of ozone. Ozone levels fall by over 60% during the worst years. In addition, research has shown that ozone depletion occurs over the latitudes that include North America, Europe, Asia, and much of Africa, Australia, and South America. Over the U.S., ozone levels have fallen 5-10%, depending on the season. Thus, ozone depletion is a global issue and not just a problem at the South Pole. Reductions in ozone levels will lead to higher levels of UVB reaching the Earth's surface. The sun's output of UVB does not change; rather, less ozone means less protection, and hence more UVB reaches the Earth. Studies have shown that in the Antarctic, the amount of UVB measured at the surface can double during the annual ozone hole. Another study confirmed the relationship between reduced ozone and increased UVB levels in Canada during the past several years. Laboratory and epidemiological studies demonstrate that UVB causes non-melanoma skin cancer and plays a major role in malignant melanoma development. In addition, UVB has been linked to cataracts. All sunlight contains some UVB, even with normal ozone levels. It is always important to limit exposure to the sun. However, ozone depletion will increase the amount of UVB, which will then increase the risk of health effects. Furthermore, UVB harms some crops, plastics and other materials, and certain types of marine life. The initial concern about the ozone layer in the 1970's led to a ban on the use of CFCs as aerosol propellants in several countries, including the U.S. However, the production of CFCs and other ozone-depleting substances grew rapidly afterward as new uses were discovered. Through the 1980s, other uses expanded and the world's nations became increasingly concerned that these chemicals would further harm the ozone layer. In 1985, the Vienna Convention was adopted to formalize international cooperation on this issue. Additional efforts resulted in the signing of the Montreal Protocol in 1987. The original protocol would have reduced the production of CFCs by half by 1998. After the original Protocol was signed, new measurements showed worse damage to the ozone layer than was originally expected. In 1992, reacting to the latest scientific assessment of the ozone layer, the Parties decided to completely end production of halons by the beginning of 1994 and of CFCs by the beginning of 1996 in developed countries. Because of measures taken under the Protocol, emissions of ozone-depleting substances are already falling. Assuming continued compliance, stratospheric chlorine levels will peak in a few years and then slowly return to normal. The good news is that the natural ozone production process will heal the ozone layer in about 50 years. In addition to regulating the end of production of the ozone-depleting substance., the U.S. Environmental Protection Agency (EPA) implements several other programs to protect the ozone layer under Title VI of the Clean Air Act. These programs include refrigerant recycling, product labeling, banning nonessential uses of certain compounds, and reviewing substitutes. EPA's Stratospheric Ozone Protection Hotline responds to inquiries and distributes information about ozone depletion and EPA's programs to protect the ozone layer. Call 1-800-296-1996 between 10 am and 4 pm Eastern Standard Time to ask questions or to order free copies of the following documents: Environmental Protection Agency
Research shows conversation quickly spreads droplets more than six feet inside buildings With implications for the transmission of diseases like COVID-19, researchers have found that ordinary conversation creates a conical, "jet-like" airflow that quickly carries a spray of tiny droplets from a speaker’s mouth across meters of an interior space. “People should recognize that they have an effect around them,” said Howard Stone, the Donald R. Dixon '69 and Elizabeth W. Dixon Professor of Mechanical and Aerospace Engineering at Princeton University. “It’s not just around your head. It is at the scale of meters.” Although scientists have not yet fully identified the transmission mechanisms of the COVID-19 virus, current research indicates that people without symptoms could infect others through tiny droplets created when they speak, sing or laugh. Stone and co-lead researcher Manouk Abkarian, of the University of Montpellier in France, wanted to learn how widely and quickly exhaled material from an average speaker could spread in an interior space. “Lots of people have written about coughs and sneezes and the kinds of things you worry about with the flu,” Stone said. “But those features are associated with visible symptoms, and with this disease we are seeing a lot of spread by people without symptoms.” In an article published Sept. 25 in the Proceedings of the National Academy of Sciences, the researchers concluded that for interior activities, normal conversations can spread exhaled material at least far as, if not beyond, social distancing guidelines recommended by the World Health Organization (1 meter) and U.S. officials (2 meters, or about 6 feet). The work examined particle flow in an interior space without good ventilation. Stone and Abkarian stressed that they are not public health experts and are not making medical recommendations. However, they said public health officials should consider the aerodynamic movement of aerosolized particles generated by speech alone as an important factor for directed spreading. “It certainly highlights the importance of ventilation,” Stone said. “Especially if you have an extended conversation.” The researchers also said that while masks do not completely block the flow of aerosols, they play a critical role in disruption of the "jet-like" air flow from a speaker’s mouth, preventing the quick transport of droplets farther than one foot. “Masks really cut this flow off tremendously,” Stone said. “This identifies why (most) masks play a big role. They cut everything off.” The researchers specialize in fluid dynamics, which describes the movement of liquids and gases. Using a high-speed camera, they film the movement of a mist of tiny droplets illuminated by a laser sheet in front of a person speaking several different phrases adjacent to the sheet. The phrases ranged from short statements like “we will beat the coronavirus” to nursery rhymes including “Peter Piper picked a peck” and “Sing a song of six pence.” The researchers selected the phrases to include different sounds that affect turbulent flows in a speaker’s exhalation. The researchers found that plosive sounds like "P" create puffs of air in front of the speaker, while a conversation created what the researchers called a “train of puffs.” Each puff creates a small vortex of air in front of the speaker, and the interaction of these vortices creates a cone-shaped "jet-like" airflow from the speaker’s mouth. The researchers found that this airflow could easily and very quickly carry tiny particles away from the speaker. Abkarian said that even a short phrase can move the particles past the 1-meter distancing recommended by the World Health Organization in a matter of seconds. The researchers said the distance depends in part on the duration of the conversation. Someone speaking for more time will send particles farther. They said that the 6-foot distancing rule may not be a sufficient barrier in an interior space without good ventilation. “If you speak for 30 seconds in a loud voice, you are going to project aerosol more than six feet in the direction of your interlocutor,” Stone said. In the paper, the researchers found that aerosols ejected during speech typically reached the 6-foot distance in about 30 seconds, and over that distance the aerosols’ concentration diluted to about 3% of the original volume. It was beyond the paper’s scope to say whether the dilution was sufficient to protect against infection, although the researchers noted that many will find this concentration to be higher than expected. The researchers said they hoped the information could help public health officials to make that determination. They also noted that longer conversations had the potential to spread more material and spread the virus over a larger distance. “More extended discussions, and meetings in confined spaces, mean that the local environment will potentially contain exhaled air over a significantly longer distance,” the researchers wrote. The researchers said the experiment showed that a social distance of 6 feet (2 meters) did not work like a wall to protect people. Over time, conversations can cause material to move past the distance, particularly inside buildings. The train of puffs created by a conversation causes a more complex turbulent flow than single jets of air and researchers had to account for it in their calculations. The researchers used the data from the experiments to create a mathematical framework to quantify the transport of droplets from the speaker’s mouth to the surrounding area. They noted that the work does not account for movement of the speaker’s head or body and background air movement caused by ventilation and other speakers. Analyzing those factors would require further work. Besides Stone and Abkarian, researchers include Simon Mendez of the University of Montpellier as well as Nan Xue and Fan Yang, graduate students in mechanical and aerospace engineering at Princeton. "Speech can produce jet-like transport relevant to asymptomatic spreading of virus," by Manouk Abkarian, Simon Mendez, Nan Xue, Fan Yang Howard A. Stone was first published September 25 in the Proceedings of the National Academy of Sciences (DOI: 10.1073/pnas.2012156117). The research was funded in part by a National Science Foundation RAPID Grant (CBET 2029370).
Current research has shown that plant sterols, which are also called phytosterols, can reduce your risk of heart disease. By eating generous amounts of fruits, vegetable, and whole grains you may even be able to significantly lower your cholesterol. What are Plant Sterols? Sterols are naturally occurring substances that are found in all plants. When vegetables, or other produce, are eaten the sterols block the absorption of cholesterol in the small intestine. Natural plant sterols have been proven to reduce dietary cholesterol. The research has been accepted by nationally recognized organizations such as the National Cholesterol Education Program and the American Dietetic Association. There have been over 140 clinical studies proving the value of sterols in a plan to reduce cholesterol. The Food and Drug Administration (FDA) has approved the health claims of the effectiveness of sterols in the diet as a way to reduce blood cholesterol. How do Sterols Work? The body gets cholesterol from only two places; diet and production of its own cholesterol. Once the cholesterol is in the digestive system it is absorbed into the cells lining the intestinal tract and taken by the blood to the liver. Plant sterols imitate cholesterol and compete with dietary cholesterol in the intestine. Since the body cannot tell the difference between the two, it will absorb either one. It doesn't need plant sterols so it returns them to the intestine and they are discarded. Therefore less cholesterol is absorbed by the body overall. Since less real cholesterol is absorbed, over time this results in a reduction of blood cholesterol levels. The sterols lower the low density cholesterol by 6 to 15 percent. Low density cholesterol, or LDL, is the type that causes the problems associated with high cholesterol levels. Sterols do not lower the high density cholesterol, or HDL, levels. High density cholesterol is the type that your body needs to function correctly. How to Get Enough Sterols The current recommendation is that sterol containing foods should be eaten twice a day. Since sterols occur naturally in very low levels it can be almost impossible to get the recommended amounts through whole foods like fruits and vegetables. In fact it would take over 100 pounds of produce or nuts to get a mere two grams of sterols. Therefore, manufacturers have begun to add phytosterols to other foods like margarine, mayonnaise, and snack bars. This helps you to get the recommended 0.8 grams of sterols per day. Side Effects and Interactions with Medicines Phytosterols do not interfere with medications that are aimed at controlling cholesterol. They do, however, interact with a few other medications. Always talk to our doctor or pharmacist about possible drug interactions. - Beta carotene should be taken at a different time of the day than sterols. Sterols can keep the body from absorbing the beta carotene properly. - Ezetimibe/Simvastatin (Vytorin) can inhibit the body's absorption of plant sterols. - Sterols can also inhibit the absorption of vitamin E and should be taken at a different time. There are also a few side effects that have been reported among users of sterols. These side effects are not usually dangerous. Among them are: - Decreased sex drive in men - Erectile dysfunction The sexual side effects may stem from the fact that sterols have a plant hormone similar to estrogen that works against testosterone. These side effects were noted in men that were being treated for enlarged prostate. There have been no serious side effects from the use of plant sterols reported. There is always the potential for an allergy to show up. Symptoms of allergic reaction would be: - Difficulty breathing If you experience any of these symptoms after taking phytosterols call your doctor or go to the emergency room. Other Uses for Phytosterols While most of the research on sterols is being done in the area of lowering blood cholesterol, some people are taking sterols for other medical problems. Some of these are: - Enhancing sexual performance - Immune system support - Treating colds and flu - Relieving the symptoms of menopause - Helping control hair loss or baldness - Relieving the symptoms of an enlarged prostate There has been some evidence that sterols can help to relieve the symptoms of enlarged prostate but do not reduce the size of the prostate itself. There is no research proving that sterols have an effect on any of the other problems. Plant sterols may be a natural way to help lower cholesterol when combined with a healthy diet and moderate exercise.
By Andy May In previous posts (here, here and here), we have shown reconstructions for the Antarctic, Southern Hemisphere mid-latitudes, the tropics, the Northern Hemisphere mid-latitudes, and the Arctic. Here we combine them into a simple global temperature reconstruction. The five regional reconstructions are shown in figure 1. The R code to map the proxy locations, the references and metadata for the proxies, and the global reconstruction spreadsheet can be downloaded here. For a description of the proxies and methods used, see part 1, here. Figure 1A, all proxies except TN057-17 on the Antarctic Polar Front Figure 1B, the proxies used for the reconstructions It is interesting that the Northern Hemisphere is the odd reconstruction. This was also true for the Marcott et al. (2013) Northern Hemisphere reconstruction from 30°N to 60°N, see figure S10f, in their supplementary materials. The Northern Hemisphere has the greatest temperature variation of the five regions and a clearly different trend. Is this because it contains most of the land? Perhaps so. It may be, in part, the impact of the melting continental glaciers from the last glacial advance. Certainly, the high Northern Hemisphere insolation, early in the Holocene due to orbital precession and obliquity played a significant role (see figure 2 in part 1, also shown for convenience as figure 2 below). In the figure, the colored curves are the seasonal changes due to precession and the background color is insolation by latitude due to obliquity changes. The black curve is the Greenland NGRIP temperature reconstruction, note that the end of the last glacial period is when both orbital obliquity and precession hit their peak insolation in the Northern Hemisphere. The labels on the curves indicate Northern Hemisphere as “N” and Southern Hemisphere as “S.” The letters after that are the first letters of the months of the year. At the beginning of the Holocene, the Northern Hemisphere summer had maximal insolation due to precession and the higher latitudes (poles) had greater insolation, due to obliquity, at the expense of the tropics. Thus, both the precession cycle and the obliquity cycle were in their warmest phases for the Northern Hemisphere mid and high latitudes. This changed a few thousand years later and the climatic equator (the Intertropical Convergence Zone) shifted and the long Neoglacial cooling period began (see figure 12, in part 2). Figure 2 (Source: Javier, see his post for a detailed explanation of the figure.) The Southern Hemisphere is also a bit anomalous, with a dip in the period of the HCO, corresponding with a dip in winter insolation in the Southern Hemisphere. The other interesting thing about the reconstructions is that the Northern Hemisphere has a higher and longer Holocene Climatic Optimum. The Northern Hemisphere was affected much more by the last glacial advance due to the large continental ice masses there. The Southern Hemisphere ice was mostly sea ice which, presumably, melts at a steadier rate with less dramatic effect. The Arctic and Antarctic each cover 6.7% of the globe, the southern and northern mid-latitudes cover 18.3% each and the tropics covers 50%. If we weight each reconstruction by the area of its region we get the reconstruction in figure 3. Figure 3A uses all proxies, except for TN057-17, which was removed in part 2. Figure 3B also eliminates ODP-658C, KY07-04-01 and OCE326-GGC26. The removal of the latter three proxies are discussed in part 2 and part 3. The two reconstructions only differ in detail. Figure 3A, all proxies Figure 3B, three additional proxies removed We will discuss the reconstruction in figure 3B since we prefer it. In this reconstruction, the depth of the Little Ice Age (LIA) occurs in 1610 AD. The apparent Medieval Warm Period (MWP) is smeared over several hundred years and occurs from around 510 AD to 1050 AD which does not fit the historical record. Oddly, only the Southern Hemisphere and the tropics show a distinct Medieval Warm Period (MWP) in its historical time. This is despite abundant historical evidence of a Northern Hemisphere MWP from around 900 AD to 1200 AD. The Antarctic reconstruction shows several warm spikes during the period, but nothing very distinct. The reason for the lack of a distinct MWP signature in the northern reconstructions is not known. In part 3 we looked at the individual proxies for the Northern Hemisphere and saw that they disagree on the presence and timing of the MWP. The Roman Warm Period (RWP) shows up well in the reconstruction, at about the right time. The “collapse of civilization” at the end of the Bronze Age is clearly seen. The 4.2 kiloyear event that led to the collapse of the Akkadian empire in 4170 BP can be seen (deMenocal, 2001). The 5.9 kyr event that occurred as the Sahara was turning into a desert, causing a great migration to the Nile valley that ultimately resulted in the Egyptian Old Kingdom is clearly seen. The LIA is the most significant climatic event of the Holocene without question, but the second most severe climatic event may well be the 8.2 kyr event. This event ended the Pre-Pottery Neolithic B culture and was when the Black Sea was catastrophically connected to the Mediterranean in an event that may be remembered as Noah’s great flood (Ryan and Pittman). The 10.3 kiloyear event takes place about the time the Pre-Pottery Neolithic period began. For more details on human history and climate change see “Climate and Human Civilization over the last 18,000 years” here. The historical climatic events match this reconstruction well, except for the MWP. The details of the regional areas are in Table 1. This table is different from the one presented in part 1 of this series because after part 1 was put up we dropped ODP-658C from the tropics reconstruction and KY07-04-01 and OCE326-GGC26 from the Northern Hemisphere reconstruction. Marcott, et al. (2013) used 73 proxies for their reconstruction and our first pass retained 31 of these and added the Rosenthal et al. (2013) Indonesian proxy for a total of 32. As the study progressed we dropped three more proxies and ended with 29. Fifty-five percent of the proxies are north of 30°N and only 21% are south of 30°S. If we simply average the 5 reconstructions with no weighting, we get the reconstruction in figure 4. Figure 4, Straight average, no weighting, final proxy set The two reconstructions are not very different. In this reconstruction, the depth of the Little Ice Age (LIA) occurs between 1530 AD and 1670 AD and the temperature anomaly is -0.84°C. The Holocene Climatic Optimum (HCO) runs from 10500 BP to 4500 BP and has numerous peaks between 0.35°C and 0.48°C. Figure 3B is similar, with a slightly larger temperature range. The average temperature difference then, in these reconstructions, is between 1.2°C and 1.4°C. This compares well to the geological and biological evidence presented in Javier, 2017. A word about error There are many sources of potential error in these reconstructions. In this series of posts, we have emphasized those sources we thought were most important and significant. Specifically, we focused on the geographic distribution of the proxies, proxy selection, the choice of the mean used to generate the temperature anomalies, the effects of proxy dropout, proxy resolution, and the impact of local conditions on the proxies. The latter problem relates to how applicable the proxy is to regional climate as opposed to local climate. Examples of inappropriate proxies due to local conditions are TN057-17 and ODP-658C which are discussed in part 2. Dating the proxy samples can be problematic. Marcott, et al. (2013) emphasize potential dating errors in their paper and supplementary materials. They consider dating errors to be the largest source of error. Marcott, et al. (2013) also provide a very detailed discussion of proxy-to-temperature calibration uncertainty in their supplementary materials. Generally, they assume one standard deviation (normally distributed) to be the error inherent in the proxy-to-temperature conversion, otherwise they follow the proxy author’s recommendations. Marcott, et al. assumed a fundamental dating error of 120 to 150 years for most cases and accounted for it using a Monte Carlo procedure (1,000 realizations) which is detailed in their supplementary materials. For the layer counted Antarctic ice-core records they assumed a ±2% uncertainty and for Greenland cores they assumed a ±1% error. All radiocarbon dates were recalibrated using IntCal09. Our reconstructions use the original published dates and not the recalibrated dates. Dating errors and proxy-to-temperature errors are undoubtedly important and Marcott et al. (2013) provide a good discussion of these problems and their supplementary database contains estimates for these sources of uncertainty. They also considered that some of the proxies may have a seasonal bias and attempted to account for this source of error in their Monte Carlo procedure. They do not believe that seasonal bias is an important source of error. We have nothing to add to their work on these uncertainties and the interested reader is referred to their paper. They do present an interesting figure in their supplementary materials displaying the 1,000 Monte Carlo realizations that result from their study of error due to dating and proxy-to-temperature conversion. It suggests that error due to these factors is roughly ±0.5°C. We show their figure as our figure 5: Figure 5 (Source: Marcott, et al., 2013 supplementary material) Marcott, et al. (2013) also provide their own latitudinal temperature reconstructions and display them in their supplementary figure S10, not reproduced here. Their regional reconstructions are different in detail than ours because they use more proxies, but their 30°N to 60°N reconstruction for the Holocene is the same big outlier we see in our figures 1A and 1B. They also note, as others have, that computer simulations of Holocene climate do not agree with the proxy reconstructions, the so-called Holocene temperature conundrum. The largest difference between the simulation results and the proxy reconstructions occurs in the mid-high latitude Northern Hemisphere, which suggests that the models are missing some key component of Northern Hemisphere climate. They suggest that the models may not be modeling north Atlantic Ocean circulation properly, we agree. The global climate models also have other problems, for a discussion see here. We believe the greater source of error in these reconstructions is in the proxy selection. As documented in this series, some of the original 73 proxies are affected by resolution issues that hide significant climatic events and some are affected by local conditions that have no regional or global significance. Others cover short time spans that do not cover the two most important climatic features of the Holocene, the Little Ice Age and the Holocene Climatic Optimum. We’ve tried to address the criticism of the Marcott et al. (2013) global temperature reconstruction. Steve McIntyre, Grant Foster and others contested their adjustments of the published proxy dates, their inclusion of some inconsistent proxies, and not compensating very well for proxy drop out. Javier has pointed out that their proxy reconstruction does not reflect abundant geological and biological evidence that the average sea surface temperatures were at least one degree Celsius warmer during the Holocene Climatic Optimum than during the Little Ice Age. In addition, the use of proxies that do not cover the interval from the LIA to the HCO is problematic since these are the two best defined temperature extremes in the period. Further, we are using temperature anomalies from the mean to build these reconstructions and prefer to get the mean from the period 9000 BP to 500BP so that the mean represents both the high temperatures of HCO and low temperatures of the LIA. This is not possible if the proxy does not cover this interval. We also avoided proxies with long sample intervals (greater than 130 years) because they tend to reduce the resolution of the reconstruction and they dampen (“average out”) important details. The smallest climate cycle is roughly 61 to 64 years, the so-called “stadium wave,” and we want to try and get close to seeing its influence. In this simple reconstruction, we have tried to address these issues. The reconstructions show a difference of 1.2°C to 1.4°C between the LIA and the HCO. This suggests that the underlying data support this temperature difference. These reconstructions also show more detail. The additional detail appears to correspond to known climatic events. While the LIA, HCO, Roman Warm Period, Minoan Warm Period and other historical events show up well in the reconstructions, the Medieval Warm Period does not, it appears dampened and offset in time from historical records. The reasons for this are unclear. As discussed in part 3, some Northern Hemisphere proxies show an MWP and some do not. The proxies may be wrong or perhaps the MWP occurred in different times or in different intensity in different places, smearing it on a global reconstruction. Either way proxy choice determines the MWP intensity and timing, which is disappointing. More work and better proxies are needed to improve our Holocene temperature record. An accurate Holocene temperature reconstruction is not possible, even measuring the potential error in a reconstruction this long is incredibly difficult. Marcott, et al. (2013) did a good job of estimating dating error and proxy-to-temperature error, in our opinion. But, they do not address the other issues, such as proxy selection, that may be more important. But, even without a viable error calculation, a generally accepted estimate of Holocene temperature trends is greatly desired. To understand the present, we must know the past. This is a very simple reconstruction and it is not meant to be definitive, but we present it as a starting point for future work. It is a presentation of the data and some useful tools needed to work the data. To improve the reconstruction, I think we need to compare it and the component proxies to other data. In particular, historical records, archeological records, glacial advance histories, biological and geological data. This “outside data” can be used to select proxies and guide the reconstruction. The R code to map the proxy locations, the references and metadata for the proxies, and the global reconstruction spreadsheet can be downloaded here. I am very grateful to Javier who has read this post and made many very helpful suggestions. Any errors are the author’s alone.
The red flour beetle, a widespread pest in flour mills, silos, and pantries, has become the fourth insect–and the first significant agricultural pest–to have its genome sequenced. The work should give scientists an even better understanding of insect biology, development, and evolution, and help them develop new ways of controlling the voracious beetle. The ubiquitous beetle–Tribolium castaneum–has been “found in every inhabited place on earth, everywhere people live and store grain,” says Richard Beeman, a research entomologist with the U.S. Department of Agriculture, who worked on the beetle project. However, there’s currently no effective way of controlling the beetle because it has developed resistance to all the chemicals that have been deployed to fight it. Many insects have evolved the ability to detoxify chemicals used against them–both those produced naturally as a defense by plants, and insecticides used in pest control. But it’s often difficult to figure out how they do it, says Barry Pittendrigh, an associate professor in the Department of Entomology at Purdue University, who was not involved in the sequencing work. But the sequencing project could help: scientists identified a number of enzymes that enable it to break down various insecticides. The research was published Sunday in an advance online version of the journal Nature. The sequencing work may also help researchers figure out new ways of combating the beetle by targeting genes that affect vital processes like digestion and the formation of the insect’s exoskeleton. “That’s one of the big hopes and promises of the genome project,” says Beeman. The researchers, for example, found more than 100 genes that are important in the synthesis of the beetle’s tough but flexible exoskeleton, providing “a huge number of potential targets,” for pest control, he says. A better understanding of how the exoskeleton is formed might also have applications in materials science. “Just imagine a football helmet made of insect chitin,” Beeman says. The sequencing work, which cost $3 to $4 million, is part of an effort to analyze the genetic codes of model organisms in order to better understand their biology, as well as the human genome. The red flour beetle is the first beetle to have its genome sequenced; the only other insects to share that honor are the fruit fly, the honeybee, and the malaria-carrying mosquito. The beetle consortium used the high-throughput sequencing facilities at Baylor College of Medicine to sequence the insect’s 16,000 genes–a fairly small genome for an insect, Beeman says. The researchers also manually analyzed about 2,000 of the beetle’s genes, focusing on those that are important in development and in pesticide resistance. The beetle is an ideal subject for genetic work because it’s easily cultured and amenable to RNA interference, which involves inserting double-stranded RNA corresponding to a particular gene into an organism so that the gene is knocked out. “We can ask, what does that beetle look like without that gene working?” Richards says. Researchers also uncovered clues to the beetle’s ability to withstand very dry conditions–down to as little as 10 percent humidity–like those found in grain storage facilities. The researchers found a gene for the receptor for vasopressin, a hormone that regulates water storage. It’s the first time that such a gene has been found in a sequenced insect, and it presumably helps the beetle survive in arid conditions, the researchers say. The gene shares the same ancestry as the vasopressin gene in humans.
As a powerful arctic cold front sweeps through the country, emergency physicians are urging people to understand cold weather health risks and take precautions to avoid cold-related medical emergencies. When temperatures drop, the risk of illness or injury can rise, especially for children and seniors. Overexposure to cold can be very dangerous, and it is easier to get hypothermia than most people think. Hypothermia occurs when your body temperature cools too fast and drops below 95 degrees Fahrenheit. Signs of hypothermia include drowsiness, confusion, slurred speech, weak pulse or shallow breathing. Slower cognitive abilities, impaired decision making and failing motor skills can make it harder to recognize and get out of danger. “One reason hypothermia is so dangerous is that you may not recognize your condition worsening,” said William P. Jaquis, MD, FACEP, president of the American College of Emergency Physicians (ACEP). “There are actually stories of people in extreme cold feeling warm, removing their winter coats and unintentionally putting themselves in even more danger.” People with certain medical conditions are more at risk, including diabetics with low blood sugar or smokers with impaired circulation. Individuals struggling with substance use disorders, mental health issues or those without stable housing are also especially susceptible to hypothermia. “It’s critical for the most vulnerable people in our communities to seek shelter and have access to dry, warm clothing when it’s this cold,” said Dr. Jaquis. “Winter storms raise the risk of car accidents, frostbite, hypothermia and other emergencies,” said Dr. Jaquis. “A little preparation goes a long way. If you encounter bad weather, try to stay off the roads and limit your time outside.” Prepare yourself for an emergency: - Gather emergency supplies in anticipation of power loss or other utility/service shutdown. - Install and maintain smoke and carbon monoxide detectors. - Heed weather reports and warnings from the experts. - Be mindful of family members’ specific needs, including medications. And, don’t forget pets! - Keep an emergency supply kit in your car that includes jumper cables, a flashlight, warm clothes and bottled water. Stay safe and keep warm out there!
Sperm in space produce healthy mouse pups on Earth Dr Ashley Cartwright Progress Educational Trust03 June 2017 Mouse sperm stored aboard the International Space Station (ISS) for nine months has been used to produce healthy pups back on Earth. Japanese researchers sent freeze-dried sperm to space to understand the long-term effects of microgravity and radiation exposure on mammalian reproduction and development. The sperm were stored at -95ºC, with researchers also using 'ground control' sperm from the same mice, stored in the same conditions on Earth for the same duration. 'We found that only a few short term studies were performed about mammalian reproduction in space, and most of them showed no clear results due to the difficulty of taking the mice or rat into space,' Professor Teruhiko Wakayama of the University of Yamanashi, who led the study, told National Geographic News. Cosmic radiation on the ISS is about 100 times greater than that on Earth, and increased radiation exposure is known to increase DNA damage in somatic and gamete cells. Once returned to Earth, the mouse sperm were compared with the control samples and assessed for damage; this included analysing their morphology, DNA, their ability to be used in fertilisation techniques, the in vitro development of subsequent embryos produced, and the normality of their offspring. The findings showed that under light microscopy, there was little difference in the morphology of the space or control sperm. However, when assessing DNA damage, there was a slight increase in damage in the sperm from space. This finding is to be expected given the known influence of radiation-associated DNA damage. While there was a difference in levels of DNA damage, when injected into mouse oocytes using artificial reproductive techniques and then transferred into recipient female mice, birth rates were found to be similar using space and control sperm. Additionally, the genomes from the space and control pups were genetically similar, suggesting that the DNA damage observed in the sperm was repaired after fertilisation. Once the mice sired from the 'space' sperm grew to adulthood, a select number were allowed to mate and breed. All mating couples produced offspring, demonstrating normal fertility. The team behind the research are planning further experiments to determine whether fertilised mouse embryos can develop normally in space. Furthermore, investigations using cryopreserved human sperm will be assessed after space storage to determine whether DNA damage and morphology can be used to determine success of artificial reproductive techniques. However, Professor Francis Cucinotta, a biophysicist at the University of Nevada in Las Vegas, points out that most damaging cosmic radiation is found 'far beyond the orbit of the ISS.' He told Science: ''There are much higher risks in deep space.' Professor Wakayama ultimately hopes once more is known about how a microgravity environment affects mammalian fertility and development, that technology could allow the storage of biological samples in space - to act both as a failsafe in case of total catastrophe on this planet, and as a recipe book for producing familiar forms of life beyond Earth as space exploration develops. The study was published in the Proceedings of the National Academy of Sciences. SOURCES & REFERENCES \|BBC \| 22 May 2017 \|Proceedings of the National Academy of Sciences \| 22 May 2017 \|National Geographic News \| 22 May 2017 \|Science \| 22 May 2017 Reproduced with permission from BioNews, an email and online sources of news, information and comment on assisted reproduction and genetics.
What exactly is a cold? Colds (or rhinitis) are the most common type of viral infection involving the upper respiratory tract, and can be caused by over 200 types of different viruses. What causes colds? Because colds are a type of viral infection, they are mainly caused by contact with other people and the spread of bacteria and viruses in indoor environments. For this reason, they occur more frequently during colder months, when people are less likely to take outdoor exercise or to ventilate their living space. What are the main symptoms of colds? The symptoms of a cold usually appear 2 or 3 days after you contract the infection, and the main ones are stuffy or runny nose and sneezing. A cold often involves not just the nose but also the throat, producing soreness and coughing. In some cases, the ears can also be affected and one of the most common by-products of a cold is otitis. The most obvious symptom of a cold is a stuffy nose, which is generally caused by two natural responses to inflammation: - Vasodilatation, or the opening of tiny blood vessels in the nostrils (nasal congestion) - Excessive production of thick, whitish mucus (rhinorrhoea) How often do colds occur and how long do they last? Adults generally catch a cold 2 to 4 times a year, but children are more susceptible to respiratory infections. Babies less than a year old only breathe through their noses and are unable to blow them, so there is a high risk that viruses will congregate inside the nasal cavities. In addition, young children's immune systems are not yet fully developed, making them more open to attack by viruses. During the first 2 years of life a child may catch up to 9 colds a year, more commonly in the winter months. The risk is higher for children who have older siblings or who go to nursery school. After age two, the immune system becomes stronger and so colds occur less frequently. If you do not have any other underlying conditions, you will usually recover from a cold in one to two weeks. How can colds be prevented and treated? For very young children, a cold can cause serious discomfort. Because they can only breathe through the nose, even pleasurable activities such as feeding and sleeping may become very difficult if the nose is congested. For this reason, it is important to take a few minor precautions to prevent and alleviate discomfort during the early stages a cold: - The most important precautionary measure is to ensure that the nose is always kept clean. If the cold has already started and your child has a stuffy nose, you can use a hypertonic solution with a natural decongestant action and without any added medication. - Teach a young child to blow his nose on his own and use nasal sprays - Use a humidifier or vaporiser to improve the quality of indoor air, or just place wet towels on radiators and ensure that you ventilate the room frequently, even in cold weather. - Do turn the heating up too high. Very young children are not yet fully able to regulate their body heat, so if you cover them with too many blankets or heat the room to above 19-20°C this can encourage them to develop a temperature. - Ensure your baby drinks a lot. This will keep the mucus in the nose more liquid and prevent the build-up of congestion, which not only makes breathing harder, but also allows infected material to collect in the paranasal sinuses and the ear canal, increasing the risk of more painful and serious conditions such as sinusitis and otitis.
Indigenous Learning Outcomes The aim of the course is to develop knowledge and skills to work effectively with Indigenous Australians in the field of psychology. In order to do so, we need to explore concepts of culture, identity, belonging, cultural positioning, and social and emotional wellbeing. The majority of work in this course will be examining self and developing an understanding of one’s own learning needs. Individual Learning Outcomes Setting your own Learning Outcomes: Consider your knowledge of “culture” in general (that being your own culture and others), and your knowledge and perception of Indigenous Australians (and be honest!). This is a time to look more broadly at the course Learning Outcomes (please see below) and consider …show more content… (approx 25 words) It is evidently clear what history thought about Indigenous Australians, and after learning this week’s content I find it appalling and quite disappointing that people would think to say such things. It made me feel embarrassed and sympathetic towards Indigenous Australians.______________________ Many Indigenous people are now accessing this information and historical documentation for many reasons for example, to trace family and/or as part of other educational studies. The impact of this on individuals, families and communities is immense and varied. We will be examining the effects and impact throughout the course. What do you know about Indigenous Australians? 4) What can you remember about the first time you heard about Indigenous Australians? For example was it at kindergarten, primary/high school, friends, at home (through your parents, siblings), family connections, workplace, media? Can you remember what was said, implied, shown about Indigenous Australians? Was it positive or negative in its message? Ensure you are using critical analysis here (approx 50 …show more content… Knowledge; It is important for practitioners to have knowledge about diversity, history, culture and contemporary realities in order to become culturally competent. The practitioner should be aware that every client is their own person, understand treaties and history of governments, know about, “communication patterns and worldviews” and understand cultural politics and organizations, (Weaver, 1999)._________________________________ 2. Skills; General skills and containment skills are relevant for culturally competent social work. General skills, including communication and problem solving, are important to be able to truly understand the client. Containment skills, “involving patience, the ability to tolerate silence and listening” and in general being less verbally active when communicating with other cultures, (Weaver, 1999).________________________________________________ 3. Values; Value themes including, “self-awareness, willing to learn, respect and social justice” are important to provide competent services. The ability for practitioners to be grounded in their own culture, to be continually educated, to set aside prejudices and be aware of special rights, is critical in becoming culturally competent, (Weaver,
In this activity on page 7 of the PDF (Chemistry—It’s Elemental), learners use iodine to identify foods that contain starch. Compare the starch content of a ripe banana, an overripe banana, milk, and flour mixed with water. Use this experiment to introduce learners to starch and how our bodies use starch to break down nutrients during digestion. Safety notes: DO NOT eat any tested foods or the iodine. Wear goggles. Follow the safety tips on the bottom of page 7 as well as Milli's safety tips on page 5.
Are you looking for the perfect counting book for toddlers or preschoolers? 1, 2, 3, Animals! was written to engage young minds while providing a solid early math foundation. One of my favorite ways to introduce, explore and review math concepts is by reading picture books with my kids. This is a non-threatening way to see math, and it provides something new and different from the regular math routine. In addition, picture books can show math in real life and provide useful visuals to help the brain make sense of concepts that are still abstract for kids. And so, I am thrilled to announce that after years of reading math picture books, I have had the privilege to write and publish my very own! This book, called 1, 2, 3, Animals! was written to introduce our youngest learners to a variety of math skills to build a solid foundation. Please Note: This post contains affiliate links which help support the work of this site. Read our full disclosure here. About the book, 1, 2, 3, Animals! A Counting Book for Toddlers In writing this story, I had several goals in mind: - Provide a fun, colorful book about animals that young kids would enjoy whether they learned any math or not - Create something different from other counting books by the variety of subitizing visuals and number representations on each page - Include a brief introduction to essential early math concepts for parents, teachers and caregivers, helping them to feel confident introducing math to children And so, the story includes simple, rhyming language, and bright, colorful illustrations to keep young kids’ interest. 1, 2, 3, Animals! also includes both the numeral and written word for each number on each page, as well as multiple opportunities to count the quantity. There are also subitizing visuals to encourage ‘seeing’ the numbers, rather than counting one by one. It is also unique, in that it counts forwards to 10 and then backwards from 10. Lastly, the book includes a brief letter explaining the math concepts and a variety of ways parents or teachers can expand on the following math skills with their kids, either while reading or after reading the story. Math Concepts to Learn & Explore: - Subitizing (seeing and knowing a quantity without counting) - Recognizing numbers 1-10 - Counting to 10 - Counting Backwards from 10 - One to One Correspondence Other Skills to Practice as You Read: In addition to exploring early math skills, this book will also provide opportunities for literacy skills as well: - Recognizing & naming animals - Early reading skills and sight word recognition - Exploring inference (drawing a conclusion about the story based on clues in the text or pictures) Ways to Extend the Math Learning with 1, 2, 3, Animals! There are so many simple ways to can learn and explore along with this book, and many are included in the introduction letter. But here are a few additional ideas for you: - Combine reading & counting with a fun snack-grab a box of animal crackers to enjoy along with the book. Give your child a handful of cookies and have them count the cookies. - Combine reading and movement-On subsequent readings, pause on each page and ask your child to move like that animal (for example, Can you stomp 3 times like an elephant?) - Combine reading & crafting-do a quick search for a craft involving one of the animals in the story (ask your child which is their favorite!). Then create one of the animals after reading. - More get up and move counting practice-on a subsequent reading, pause on each page and ask your child to find that number of things somewhere around the room (for example, can you find 4 of something around you?) Pre-Order BONUSES with 1, 2, 3, Animals! Ready to pre-order a copy for yourself or a friend? I’m excited to share that you can receive BONUS freebies to use along with the book to help your child build some of these foundational math skills! As a thank you for pre-ordering before the official release date on April 21, 2020, you can receive the following bonuses: - A set of coloring pages featuring animals from the book (a great way to keep little ones occupied while you read aloud!) - My set of dot cards to use with 10 different math games (help kids build subitizing skills, counting skills, plus addition & subtraction skills when they’re ready) If you have already ordered your copy, you can fill out this proof of purchase form here to request your bonuses. If not, learn more about the book and order a copy HERE. Then fill out the form above so I can send you your bonuses! I will get your bonuses to you ASAP, so you can begin enjoying the pages and games while you wait for the book to arrive! Please note: this is ONLY valid for pre-orders, meaning purchases made before the book is released April 21. Never Run Out of Fun Math Ideas If you enjoyed this post, you will love being a part of the Math Geek Mama community! Each week I send an email with fun and engaging math ideas, free resources and special offers. Join 124,000+ readers as we help every child succeed and thrive in math! PLUS, receive my FREE ebook, 5 Math Games You Can Play TODAY, as my gift to you!
- Restrictions on Access: - Unclassified, Unlimited, Publicly available. - What happens when a large impact event takes place on a satellite with a thin crust and lithosphere? In the early Solar System impact cratering and volcanism were the dominate processes shaping the surfaces of the terrestrial planets. Impact events may have triggered additional volcanism by uplifting partially molten mantle material to the surface, where it melts due to pressure release. Subsequently, the shattered crust may have provided pathways for magma to reach the surface creating a longer term hot spot. As the crusts of the terrestrial planets thickened, the ability of impacts to trigger volcanism diminished . However, the highly-volcanic jovian satellite Io is located in a "high-impact" area of the Solar System , a victim of material attracted by Jupiter s gravitational field. In 1994 huge impacts were observed when fragments of comet Shoemaker- Levy 9 impacted Jupiter. The large icy satellites of Jupiter (Europa, Ganymede and Callisto) are pockmarked with many impact craters. Yet no impact features have been found on Io . This is because of rapid resurfacing of Io due to volcanism, estimated at approx.1 cm/year which over short geological time erases evidence of impacts. Io, however, has a lithosphere over a molten or partially-molten mantle [e.g., 5], and the effects of a sufficiently large impact may extend far beyond the evolution of the impact crater alone. At least one example of impact-triggered volcanism may exist in the Solar System today: the Loki Patera complex on Io. - NASA Technical Reports Server (NTRS) Collection. - Document ID: 20050176446. Lunar and Planetary Science XXXVI, Part 19; LPI-Contrib-1234-Pt-19. - Copyright, Distribution under U.S. Government purpose rights. View MARC record \| catkey: 15414286
Nyāya (Sanskrit ni-āyá, literally "recursion", used in the sense of "syllogism, inference") is the name given to one of the six orthodox or astika schools of Hindu philosophy—specifically the school of logic. The Nyaya school of philosophical speculation is based on texts known as the Nyaya Sutras, which were written by Aksapada Gautama from around the 2nd century. The most important contribution made by the Nyaya school to modern Hindu thought is its methodology to prove existence of God, based on the Vedas. This methodology is based on a system of logic that, subsequently, has been adopted by the majority of the other Indian schools, orthodox or not. This is comparable to how Western science and philosophy can be said to be largely based on Aristotelian logic. However, Nyaya differs from Aristotelian logic in that it is more than logic in its own right. Its followers believed that obtaining valid knowledge was the only way to obtain release from suffering. They therefore took great pains to identify valid sources of knowledge and to distinguish these from mere false opinions. Nyaya is thus a form of epistemology in addition to logic. According to the Nyaya school, there are exactly four sources of knowledge (pramanas): perception, inference, comparison, and testimony. Knowledge obtained through each of these can, of course, still be either valid or invalid. As a result, Nyaya scholars again went to great pains to identify, in each case, what it took to make knowledge valid, in the process creating a number of explanatory schemes. In this sense, Nyaya is probably the closest Indian equivalent to contemporary analytic philosophy. Sixteen Padārthas or Categories The Nyaya metaphysics recognizes sixteen padarthas or categories and includes all six (or seven) categories of the Vaisheshika in the second one of them, called prameya. These sixteen categories are pramāṇa (valid means of knowledge), prameya (objects of valid knowledge), saṁśaya (doubt), prayojana (aim), dṛṣṭānta (example), siddhānta (conclusion), avayava (members of syllogism), tarka (hypothetical reasoning), nirṇaya (settlement), vāda (discussion), jalpa (wrangling), vitaṇḍā (cavilling), hetvābhāsa (fallacy), chala (quibbling), jāti (sophisticated refutation) and nigrahasthāna (point of defeat). The Nyaya epistemology considers knowledge (jñāna) or cognition (buddhi) as apprehension (upalabdhi) or consciousness (anubhava). Knowledge may be valid or invalid. The Naiyayikas (the Nyaya scholars) accepted four valid means (pramaṇa) of obtaining valid knowledge (prama) - perception (pratyakṣa), inference (anumāna), comparison (upamāna) and verbal testimony (śabda). Invalid knowledge includes memory (smṛti), doubt (saṁśaya), error (viparyaya) and hypothetical reasoning (tarka). Pratyakṣa (perception) occupies the foremost position in the Nyaya epistemology. Perception is defined by Akṣapāda Gautama in his Nyaya Sutra (I,i.4) as a 'non-erroneous cognition which is produced by the intercourse of sense-organs with the objects, which is not associated with a name and well-defined'. Perception can be of two types, laukika (ordinary) and alaukika (extraordinary). Ordinary (Laukika or Sadharana) perception is of six types - visual-by eyes, olfactory-by nose, auditory-by ears, tactile-by skin, gustatory-by tongue and mental-by mind. Extraordinary (Alaukika or Asadharana) perception is of three types, viz., Samanyalakshana (perceiving generality from a particular object), Jñanalakshana (when one sense organ can also perceive qualities not attributable to it, as when seeing a chili, one knows that it would be bitter or hot), and Yogaja (when certain human beings, from the power of Yoga, can perceive past, present and future and have supernatural abilities, either complete or some). Determinate and indeterminate perception The Naiyayika maintains two modes or stages in perception. The first is called nirvikalpa (indeterminate), when one just perceives an object without being able to know its features, and the second savikalpa (determinate), when one is able to clearly know an object. All laukika and alaukika pratyakshas are savikalpa, but it is necessarily preceded by an earlier stage when it is indeterminate. Vātsāyana says that if an object is perceived with its name we have determinate perception but if it is perceived without a name, we have indeterminate perception. Jayanta Bhatta says that indeterminate perception apprehends substance, qualities and actions and universals as separate and indistinct something and also it does not have any association with name, while determinate perception aprrehends all these together with a name. There is yet another stage called Pratyabhijñā, when one is able to re-recognise something on the basis of memory. Anumāna (inference) is one of the most important contributions of the Nyaya. It can be of two types: inference for oneself (Svarthanumana, where one does not need any formal procedure, and at the most the last three of their 5 steps), and inference for others (Parathanumana, which requires a systematic methodology of 5 steps). Inference can also be classified into 3 types: Purvavat (inferring an unperceived effect from a perceived cause), Sheshavat (inferring an unperceived cause from a perceived effect) and Samanyatodrishta (when inference is not based on causation but on uniformity of co-existence). A detailed anaysis of error is also given, explaining when anumana could be false. Upamāna, which can be roughly translated as comparison is the knowledge of the relationship between a word and the object denoted by the word. It is produced by the knowledge of resemblance or similarity, given some pre-description of the new object beforehand. Śabda or verbal testimony is defined as the statement of a trustworthy person (āptavākya), and consists in understanding its meaning. It can be of two types, Vaidika (Vedic), which are the words of the four sacred Vedas, and are described as the Word of God, having been composed by God, and Laukika, or words and writings of trustworthy human beings. Vaidika testimony is preferred as the infallible word of God, and Laukika testimony must by its nature be questioned and overruled by more trustworthy knowledge if such becomes available. Theory of inference The methodology of inference involves a combination of induction and deduction by moving from particular to particular via generality. It has five steps, as in the example shown: - There is fire on the hill (called Pratijñā, required to be proved) - Because there is smoke there (called Hetu, reason) - Wherever there is smoke, there is fire, e.g. in a kitchen (called Udāhārana, example of vyāpti) - The hill has smoke that is pervaded by fire (called Upanaya, reaffirmation or application) - Therefore there is fire on the hill (called Nigamana, conclusion) In Nyāya terminology for this example, the hill would be called as paksha (minor term), the fire is called as sādhya (major term), the smoke is called as hetu, and the relationship between the smoke and the fire is called as vyāpti(middle term). Hetu further has five characteristics: (1) It must be present in the Paksha, (2) It must be present in all positive instances, (3) It must be absent in all negative instances, (4) It must not incompatible with the minor term or Paksha and (5) All other contradictions by other means of knowledge should be absent. The fallacies in Anumana (hetvābhasa) may occur due to the following: - Asiddha: It is the unproved hetu that results in this fallacy. [Paksadharmata] - Ashrayasiddha: If Paksha [minor term] itself is unreal, then there cannot be locus of the hetu. e.g. The sky-lotus is fragrant, because it is a lotus like any other lotus. - Svarupasiddha: Hetu cannot exist in paksa at all. E.g. Sound is a quality, because it is visible. - Vyapyatvasiddha: Conditional hetu. `Wherever there is fire, there is smoke'. The presence of smoke is due to wet fuel. - Savyabhichara: This is the fallacy of irregular hetu. - Sadharana: The hetu is too wide. It is present in both sapaksa and vipaksa. `The hill has fire because it is knowable'. - Asadharana: The hetu is too narrow. It is only present in the Paksha, it is not present in the Sapaksa and in the Vipaksha. `Sound is eternal because it is audible'. - Anupasamhari: Here the hetu is non-exclusive. The hetu is all-inclusive and leaves nothing by way of sapaksha or vipaksha. e.g. 'All things are non-ternal, because they are knowable'. - Satpratipaksa: Here the hetu is contradicted by another hetu. If both have equal force, then nothing follows. 'Sound is eternal, because it is audible', and 'Sound is non-eternal, because it is produced'. Here 'audible' is counter-balanced by 'produced' and both are of equal force. - Badhita: When another proof (as by perception) definitely contradicts and disproves the middle term (hetu). 'Fire is cold because it is a substance'. - Viruddha: Instead of proving something it is proving the opposite. 'Sound is eternal because it is produced'. The Nyaya theory of causation A cause is defined as an unconditional and invariable antecedent of an effect and an effect as an unconditional and invariable consequent of a cause. The same cause produces the same effect; and the same effect is produced by the same cause. The cause is not present in any hidden form whatsoever in its effect. The following conditions should be met: - The cause must be antencedent [Purvavrtti] - Invariability [Niyatapurvavrtti] - Unconditionality [Ananyathasiddha] Nyaya recognizes five kinds of accidental antecedents [Anyathasiddha] - Mere accidental antecedent. E.g., The colour of the potter's cloth. - Remote cause is not a cause because it is not unconditional. E.g., The father of the potter. - The co-effects of a cause are not causally related. - Eternal substances, or eternal conditions are not unconditional antecedents. e.g. space. - Unnecessary things, e.g. the donkey of the potter. Nyaya recognizes three kinds of cause: - Samavayi, material cause. E.g. Thread of a cloth. - Asamavayi, colour of the thread which gives the colour of the cloth. - Nimitta', efficient cause, e.g. the weaver of the cloth. Anyathakyativada of Nyaya The Nyaya theory of error is similar to that of Kumarila's Viparita-khyati (see Mimamsa). The Naiyayikas also believe like Kumarila that error is due to a wrong synthesis of the presented and the represented objects. The represented object is confused with the presented one. The word 'anyatha' means 'elsewise' and 'elsewhere' and both these meanings are brought out in error. The presented object is perceived elsewise and the represented object exists elsewhere. They further maintain that knowledge is not intrinsically valid but becomes so on account of extraneous conditions (paratah pramana during both validity and invalidity). Nyaya on God and salvation Early Naiyayikas wrote very little about Ishvara (literally, the Supreme Soul). However, later Buddhists in India had become from agnostic to strictly atheistic. As a reaction, the later Naiyayikas entered into disputes with the Buddhists and tried to prove the existence of God on the basis of inference. They made this question a challenge to their own existence. Udayana's Nyayakusumanjali gave the following nine arguments to prove the existence of creative God: - Kāryāt (lit. "from effect"): An effect is produced by a cause, and similarly, the universe must also have a cause. Causes (according to Naiyayikas) are of three kinds: Samavayi (in case of the universe, the atoms), Asamavayi (the association of atoms) and Nimitta (which is Ishvara). The active cause of the world must have an absolute knowledge of all the material of creation, and hence it must be God. Hence from the creation, the existence of the Creator is proved. - Āyojanāt (lit., from combination): Atoms are inactive and properties are unphysical. So it must be God who creates the world with his will by causing the atoms to join. Self-combination of inanimate and lifeless things is not possible, otherwise atoms would only combine at random, creating chaos. There is to be seen the hand of a wise organizer behind the systematic grouping of the ultimate atoms into dyads and molecules. That final organizer is God. - Dhŗtyādéḥ(lit., from support): Just as a material thing falls off without a support, similarly, God is the supporter and bearer of this world, without which the world would not have remained integrated. This universe is hence superintended within God, which proves his existence. - Padāt (lit., from word): Every word has the capability to represent a certain object. It is the will of God that a thing should be represented by a certain word. Similarly, no knowledge can come to us of the different things here unless there is a source of this knowledge. The origin of all knowledge should be omniscient and, consequently, omnipotent. Such a being is not to be seen in this universe, and so it must be outside it. This being is God. - Pratyayataḥ (lit, from faith): the Hindu holy scriptures, the Vedas, are regarded as the source of eternal knowledge. Their knowledge is free from fallacies and are widely believed as a source of proof. Their authors cannot be human beings because human knowledge is limited. They cannot obtain knowledge of past, present, and future, and in depth knowledge of mind. Hence, only God can be the creator of the Vedas. Hence, his existence is proved from his being the author of the Vedas, which he revealed to various sages over a period of time. - Shrutéḥ (lit., from scriptures): The Shrutis, e.g., the Vedas extol God and talk about his existence. "He is the lord of all subjects, omniscient, and knower of one's internal feelings; He is the cause, maintainer, and destroyer of the world", say the Shrutis. The Shrutis are regarded as a source of proofs by Naiyanikas. Hence, the existence of God is proved. - Vākyāt (lit., from precepts): World is governed by moral laws that are objective and universal. These are again manifested by Shrutis. Hence there exists God, the promulgator of these laws. - Samkhyāviśeşāt (lit., from the specialty of numbers):According to the Nyaya, the magnitude of a dyad is produced by the number of two atoms. The number "one" is directly perceived but other numbers are created by perceptions, which is related to the mind of the perceiver. Since at the time of creation, souls, atoms, Adŗşţa (Unseen Power), space, time and minds are all unconscious, hence it depends on divine consciousness. So God must exist. - Adŗşţāt (lit., from the unforeseen): Everybody reaps the fruits of his own actions. merits and demerits accrue from his own actions and the stock of merit and demerit is known as Adŗşţa, the Unseen Power. But since this unseen power is unintelligent, it needs the guidance from a supremely intelligent god. Not only have the Naiyayikas provided arguments to prove the existence of God, but they have also given an argument that such a God can only be one. In the Nyayakusumanjali, this is discussed against the proposition of the Mimamsa school—that let us assume there were many gods (Devas) and sages (rishis) in the beginning, who wrote the Vedas and created the world. Udayana says that: [if they assume such] omniscient beings, those endowed with the various superhuman faculties of assuming infinitesimal size, and so on, and capable of creating everything, then we reply that the law of parsimony bids us assume only one such, namely Him, the adorable Lord. There can be no confidence in a non-eternal and non omniscient being, and hence it follows that according to the system which rejects God, the tradition of the Veda is simultaneously overthrown; there is no other way open. In other words, Udayana says that the polytheist would have to give elaborate proofs for the existence and origin of his several celestial spirits, none of which would be logical. So it is much more logical to assume only one, eternal and omniscient God. The Naiyayikas believe that the bondage of the world is due to false knowledge, which can be removed by constantly thinking of its opposite (pratipakshabhavana), namely, the true knowledge. So the opening aphorism of the Nyāya Sūtra states that only the true knowledge lead to niḥśreyasa (salvation). But the Nyaya school also maintains that the God's grace is essential for obtaining true knowledge. Jayanta, in his Nyayamanjari describes salvation as a passive stage of self in its natural purity, unassociated with pleasure, pain, knowledge and willingness. Literature of Nyaya The earliest text of the Nyāya School is the Nyāya Sūtra of Udyotakara’s Nyāya Vārttika (6th century CE) is written to defend Vātsāyana against the attacks made by Dignāga. Vācaspati Miśra’s Nyāyavārttikatātparyaṭīkā (9th century CE) is the next major exposition of this school. Two other texts, Nyāyaṣūcinibandha and Nyāyasūtraddhāra are also attributed to him. Udayana’s (984 CE) Nyāyatātparyapariśuddhi is an important commentary on Vācaspati’s treatise. His Nyāyakusumāñjali is the first systematic account of theistic Nyāya. His other works include Ātmatattvaviveka, Kiraṇāvali and Nyāyapariśiṣṭa. Jayanta Bhatta’s Nyāyamañjari (10th century CE) is basically an independent work. Bhāsavarajña’s Nyāyasāra (10th century CE) is a survey of Nyāya philosophy. The later works on Nyāya accepted the Vaiśeṣika categories and Varadarāja’s Tārkikarakṣā (12th century CE) is a notable treatise of this syncretist school. Keśava Miśra’s Tārkabhaṣā (13th century CE) is another important work of this school. Gangeśa Upādhyāya’s Tattvacintāmaṇi (12th century CE) is the first major treatise of the new school of Navya Nyāya. His son, Vardhamāna Upādhyāya’s Nyāyanibandhaprakāśa (1225 CE), though a commentary on Udayana’s Nyāyatātparyapariśuddhi, incorporated his father’s views. Jayadeva wrote a commentary on Tattvacintāmaṇi known as Āloka (13th century CE). Vāsudeva Sārvabhauma’s Tattvacintāmaṇivyākhyā (16th century CE) is first great work of Navadvipa school of Navya Nyāya. Raghunātha Śiromaṇi’s Tattvacintāmaṇidīdhiti and Padārthakhaṇḍana are the next important works of this school. edit] See also - Aksapada Gautama - Indian logic - Hindu philosophy - Gautama Maharishi - List of teachers of Nyaya - ^ Sharma, C. (1997). A Critical Survey of Indian Philosophy, Delhi: Motilal Banarsidass, ISBN 81-208-0365-5, p.192 - ^ Hiriyanna, M. (1993, reprint 2000). Outlines of Indian Philosophy, Delhi: Motilal Banarsidass, ISBN 81-208-1099-6, pp.245,245n - ^ a b Chattopadhyaya, D. (1986), Indian Philosophy: A Popular Introduction, People’s Publishing House, New Delhi, ISBN 81-7007-023-6, p.163 - ^ a b c Sharma, C. (1997). A Critical Survey of Indian Philosophy, Delhi: Motilal Banarsidass, ISBN 81-208-0365-5, pp.192-6 - ^ Sharma, C. (1997). A Critical Survey of Indian Philosophy, Delhi: Motilal Banarsidass, ISBN 81-208-0365-5, pp.209-10 - ^ Dasgupta, Surendranath (1975). A History of Indian Philosophy, Vol. I, Delhi: Motilal Banarsidass, ISBN 81-208-0412-8, p.365 - ^ Sharma, C. (1997). A Critical Survey of Indian Philosophy, Delhi: Motilal Banarsidass, ISBN 81-208-0365-5, p.208 - ^ Dasgupta, Surendranath (1975). A History of Indian Philosophy, Vol. I, Delhi: Motilal Banarsidass, ISBN 81-208-0412-8, p.366 - ^ Radhakrishnan, S. Indian Philosophy, Vol. II, Oxford University Press, New Delhi, 2006, ISBN 0-19-563820-4, pp.36-40 - ^ Radhakrishnan, S. Indian Philosophy, Vol. II, Oxford University Press, New Delhi, 2006, ISBN 0-19-563820-4, p.40 - ^ a b Radhakrishnan, S. Indian Philosophy, Vol. II, Oxford University Press, New Delhi, 2006, ISBN 0-19-563820-4, p.41 - Extracts from Nyaya Kusumanjali by Udayana - A Vedantin source about God's existence - Mishra, M, 1999, Bhāratīya Darshan, Kala Prakashan, Varanasi. - Nyaya doctrine at the Darshana Indian Philosophy site. - Indian Systems of Logic (Nyaya): A Survey: Prof. V.V.S. Sarma - Lectures on Sri Annam Bhatta's Tarka Sangraha and Other Works on Nyaya Shastra at Shastranethralaya. 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Look at other dictionaries: Nyaya — (Sanskrit: Regel, Methode, Analyse) ist eines der sechs orthodoxen Systeme der indischen Philosophie. Das Nyaya setzt sich vorrangig mit den Themengebieten Epistemologie und Logik auseinander, und legte innerhalb dieses Rahmens einige Standards… … Deutsch Wikipedia Nyaya — Nyâya Religions Védisme Brahmanisme Hindouisme Ajîvika Jaïnisme … Wikipédia en Français Nyâya — Nyāya est la sixième et dernière école « orthodoxe » (sanskrit en devanāgarī: न्याय; signifie: la « méthode », le « système » ou la « règle »), sans doute fondée par le brahmane Akshapāda Gautama, est… … Wikipédia en Français NYAYA — NY YA L’un des darshanas de la tradition brahmanique, celui qui correspond à la logique. Cette tradition, en effet, répartit la matière des spéculations philosophiques visant à l’interpréter en six approches possibles, qu’elle nomme darshanas… … Encyclopédie Universelle Nyaya — [Sanskrit »Regel«, »Prinzip«, »Methode«] der, , das System der Logik, eines der sechs Systeme der klassischen indischen Philosophie, das im 2. Jahrhundert n. Chr. von einem Handbuch für Disputationsregeln ausging, in das Elemente einer… … Universal-Lexikon nyaya — NYÁYA s.f. Şcoală filozofică indiană, potrivit căreia lumea există obiectiv şi se compune din atomi necreaţi de divinitate, pe care aceasta numai îi combină. [< sanscr. nyaya – temei, metodă]. Trimis de LauraGellner, 24.06.2005. Sursa: DN … … Dicționar Român Nyaya — /nyah yeuh/, n. (in ancient India) a philosophical school emphasizing logical analysis of knowledge, which is considered as deriving from perception, inference, analogy, and reliable testimony. [ < Skt nyaya] * * * One of the six darshans… … Universalium Nyaya — (Skt., logical analysis) One of the six orthodox Hindu schools (darshanas ). The Nyaya (or, in its alliance with Hindu metaphysics of nature, the Nyaya–Vaisheshika ) school concentrates upon our knowledge of reality. Perception, inference,… … Philosophy dictionary nyaya — ˈnyäyə noun ( s) Usage: usually capitalized Etymology: Sanskrit nyāya rule, model, maxim, logic, from ni down, back (i.e., to an original model) + eti he goes more at nether, issue … Useful english dictionary Nyāya — El niaiá es uno de los seis darshana o doctrinas ortodoxas (astika) hinduistas. न्याय, en escritura devánagari. nyāya, en el sistema IAST de transliteración sánscrita. Pronunciación: niaiá. Etimología: deriva de la raíz sánscrita ní, que… … Wikipedia Español
Researchers at the University of Zurich have discovered a protein that enables adenoviruses to infect human cells. The Mib1 protein gives the virus the signal to uncoat the DNA and release it into the nucleus. Blocking this protein could therefore help people with weakened immune systems to fight dangerous viruses. Viruses have been part of animals and humans for eons. When viruses invade a cell, they can infiltrate the nucleus with their genome and become part of the genome of the infected organism. Viruses transfer their genes between various organisms, as well as between tissues containing well differentiated cells inside a living creature. But how they uncoat their well-packed genes and release them to cause infection is largely unknown. Mib1 protein systematically controls virus infection The research group of Urs Greber, professor at the Institute of Molecular Life Sciences of the University of Zurich (UZH), has now for the first time identified a protein in human cells that is key for successful viral DNA uncoating: the ubiquitin-ligase Mind bomb 1 (Mib1). “The protein enables adenoviruses to uncoat their DNA and discharge it into the nucleus – which is necessary for successful infection,” says Greber. If the protein is not produced or fails to work properly, the viruses can penetrate into the cell and reach the nuclear membrane, but they remain stuck on the porous structures of the nuclear envelope. “This finding opens up a new possibility for developing anti-viral therapies that block Mib1 in well differentiated cells,” says Greber. At present, there are no effective drugs to combat these widespread viruses. Looking for the door handle at the nucleus entrance Researchers found the protein by switching off most of the genes in human cells of the lung epithelium using RNA interference one by one, and then testing whether adenoviruses could infect the cells. “When we inhibited the gene for Mib1 or knocked it out using CRISPR-Cas technology, the virus infection rate declined drastically. Practically all adenoviruses remained stuck at the pore structures outside of the nucleus,” says Greber. As soon as these cells, after genetic interventions, produced small amounts of Mib1 again, the Mib1 reached the viruses at the nuclear pores, and the viruses uncoated their genes and infected the cells. Reference: Bauer et al. (2019) The E3 Ubiquitin Ligase Mind Bomb 1 Controls Adenovirus Genome Release at the Nuclear Pore Complex. Cell Reports. DOI: https://doi.org/10.1016/j.celrep.2019.11.064 Source: Technology Networks
Body Mass Index (BMI) Charts For years, doctors have used height and weight measurements to assess a child’s physical growth in relation to other kids the same age. Now they have another tool: body mass index (BMI). BMI is a calculation that uses height and weight to estimate how much body fat someone has. Doctors use it to determine how appropriate a child’s weight is for a certain height and age. You can use the BMI calculator below to determine your child’s BMI, but it’s also important to have your doctor perform regular BMI measurements. That way, you’ll know the number is accurate and the doctor can discuss the results with you. Starting when your child is 2 years old, the doctor will determine BMI at routine checkups and plot this measurement on a chart against those of other kids the same age. Because what is normal changes with age, doctors must plot children’s BMI measurements on standard growth charts rather than using a universal normal range for BMI as is done with adults. They also use separate charts for boys and girls to account for differences in growth rates and amounts of body fat as the two genders mature. That information is recorded in your child’s medical record, and over several visits the pattern of measurements allows the doctor to track your child’s growth. BMI is particularly helpful for identifying kids and adolescents who are at risk for becoming significantly overweight as they get older. In older kids and teens, there is a strong correlation between BMI and the amount of body fat. So those with high BMI readings — and, probably, high levels of fat — are most likely to have weight problems when they are older. By identifying these at-risk kids, doctors can monitor their body fat carefully and try to prevent adult obesity through changes in eating and exercise habits. What the Figures Mean BMI percentiles show how kids’ measurements compare with others the same gender and age. For example, if a child has a BMI in the 60th percentile, 60% of the kids of the same gender and age who were measured had a lower BMI. BMI is not perfect. For example, it’s very common for kids to gain weight quickly — and see the BMI go up — during puberty. Your doctor can help you figure out whether this weight gain is a normal part of development or whether it’s something to be concerned about. Kids can also have a high BMI if they have a large frame or a lot of muscle, not excess fat. And a kid with a small frame may have a normal BMI but too much body fat. Although BMI is not a direct or perfect measure of body fat, kids at or above the 95th percentile are considered obese, a term doctors use to indicate excess body fat, which increases the risk of weight-related health problems. Kids who measure at the 85th to 94th percentiles are considered overweight, because of excess body fat or high lean body mass. A child whose BMI is between the 5th percentile to 85th percentile is in the healthy weight range. A child with a BMI below the 5th percentile is considered underweight. Also, it’s important to look at the BMI numbers as a trend instead of focusing on individual numbers. Any one measurement, taken out of context, can give you the wrong impression of your child’s growth. The real value of BMI measurements lies in viewing them as a pattern over time. That allows both doctor and parents to watch a child’s growth and determine whether it’s normal compared with that of other kids the same age. While BMI is an important indicator of healthy growth and development, if you think your child may be gaining or losing weight too fast, talk to your doctor. Reviewed by: Mary L. Gavin, MD Date reviewed: September 2013
Trachoma is the world’s leading infectious cause of blindness and one of 20 neglected tropical diseases (NTDs) that affect over one billion of the world’s poorest people. It is caused by the bacterium Chlamydia trachomatis. The bacteria are spread through contact with eye discharge from an infected person – via hands, towels and sheets. Trachoma thrives in areas where there is poor sanitation and limited access to water for personal hygiene. Repeated infection damages the eyelids causing the eyelashes to turn inwards and rub painfully against the eyeball surface. This advanced stage of the disease, trachomatous trichiasis, is extremely painful and has a profoundly negative impact on an individual’s quality of life. Trichiasis can be corrected by eyelid surgery, however if left untreated it may lead to irreversible vision loss and blindness. Trachoma is estimated to be responsible for the visual impairment of about 1.9 million people, of whom 1.2 million are irreversibly blind, with approximately 157.7 million people worldwide living in trachoma-endemic districts. Trachoma can destroy the economic well-being of entire communities, keeping affected families trapped in a cycle of poverty as the disease passes from one generation to the next. While children are the most susceptible to infection, the blinding effects of repeated infection do not usually develop until adulthood. Women are up to four times more likely than men to develop trichiasis, in part because of repeated exposure to their children's infections. The disabling effects of vision loss further compound other common challenges faced by poor and marginalized people. In 1996, the World Health Organization (WHO) Alliance for the Global Elimination of Trachoma by 2020 (GET 2020 Alliance) was created to address this health and development issue. The GET2020 Alliance is the principal platform through which the trachoma community works together towards a shared goal. It includes representatives from country governments as well as other non-government organizations (NGOs), academic institutions, donors and private sector stakeholders. Adding further support to the Alliance, in May 1998, the 51st World Health Assembly adopted a resolution calling for the elimination of trachoma as a public health problem and recommended that ministries of health implement the SAFE strategy in endemic areas (WHA Resolution 51.11). The WHO-recommended SAFE strategy consists of surgery (S), antibiotics (A), facial cleanliness (F) and environmental improvement (E) interventions. The antibiotics component of the SAFE strategy aims to reduce the prevalence of active disease in a population while the surgery component provides corrective surgery to people with the blinding stage of the disease. Facial cleanliness and environmental improvement interventions help to reduce rates of transmission and are critical for the sustainability of trachoma elimination. Importantly, trachoma interventions are undertaken within national health systems and integrated into national priorities, contributing to health system strengthening through the building of knowledge, skills and capacity. For more information about the story of trachoma, read Katherine Schlosser's article on the history of trachoma. Trachoma - a devastating infectious eye disease made by Dr Ranil Appuhamy
Scientists identify two new species of fungi in retreating Arctic glacier Two new species of fungi have made an appearance in a rapidly melting glacier on Ellesmere Island in the Canadian Arctic, just west of Greenland. A collaborative team of researchers from Japan’s National Institute of Polar Research, The Graduate University for Advanced Studies in Tokyo, Japan, and Laval University in Québec, Canada made the discovery. The scientists published their results on 3 January 2019 in two separate papers, one for each new species, in the International Journal of Systematic and Evolutionary Microbiology. “The knowledge of fungi inhabiting the Arctic is still fragmentary. We set out to survey the fungal diversity in the Canadian High Arctic,” said Masaharu Tsuji, a project researcher at the National Institute of Polar Research in Japan and first author on both papers. “We found two new fungal species in the same investigation on Ellesmere Island.” One species is the 10th to join the genus Mrakia, with the proposed name M. hoshinonis, in honor of Tamotsu Hoshino, a senior researcher at the National Institute of Advanced Science and Technology in Japan. Hoshino has made significant contributions to the study of fungi in polar regions. The other species is the 12th to join the genus Vishniacozyma, with the proposed name V. ellesmerensis as a nod to the island where it was found. Both species are types of yeast that are well-adapted to the cold and can even grow below 0°C. The samples of fungi were collected from the unofficially named Walker Glacier. The designation comes from Paul T. Walker, who installed the datum pole that measures the glacier’s growth and shrinkage, in 1959. At the time of sample collection in 2016, measurements showed that the glacier was receding at a rate two-and-a-half times faster than its retreat over the previous 50 years. “Climate-related effects have been observed in this region over the last 20 years,” Tsuji said. “Soon, some of the glaciers may completely melt and disappear.” Only about five percent of fungi species have been discovered, but their function across ecological climates is well understood – from the tropics to the Arctic, fungi decompose dead organic material. Each species operates a little differently, but their general role is to reintroduce nutrients from dead plant material back into the ecosystem. If the glaciers melt, the fungi lose their habitat. The results could have catastrophic knock-on effects throughout the ecosystem, according to Tsuji, although more research is needed to understand exactly how the changing climate is influencing fungi beyond destroying their habitat. Next, Tsuji and his team plan to survey the fungi in Ward Hunt Lake, the northern most lake in the world. It is on Ward Hunt Island, just off the northern coast of Ellesmere Island, and less than 500 miles from the North Pole “Normally, the lake’s ice doesn’t melt during the summer season. However, the ice melted completely in 2016. We plan to continuously check how the lake’s fungal diversity changes,” Tsuji said. The different species could evolve, or, potentially, go extinct. “Eventually, we plan to compile all of our studies to provide an overview of terrestrial ecosystems in the Arctic and Antarctic regions.”
The benefits of outdoor learning and development From playing on tablets to watching TV, children are becoming more accustomed to learning with technology, especially at a younger age. However, this has led to a number of studies that highlight how negative this can be for their education and development. In this article, we wanted to explore some of the ways that parents and teachers can utilise the outdoor space around them, to help children learn and develop in a natural environment. Instilling active lifestyles Whilst there are benefits to teaching indoors, learning outdoors helps instil an active lifestyle in children from a young age. Not only does this help them later in life, but it also helps them whilst they’re still growing. When learning outside, they’re often more active, which helps build strong bones and increase their fitness levels, whilst burning off extra calories and energy. As easy as it might be to shield children from environments that might challenge them, it is sometimes a good thing to let them identify challenges and overcome them by themselves. By letting them learn outdoors, they are able to understand how to see things through, how their actions impact everything around them, and how not to back down as soon as something becomes harder to accomplish. When given the opportunity to learn in a new environment, some children will naturally take it upon themselves to find out what they can do by themselves. They’re able to play and learn, away from adult supervision, which gives them the chance to socially interact, take turns when playing games and negotiate unfamiliar surroundings. Developing social skills As outdoor learning spaces are less crowded than indoor spaces, it gives children the opportunity to help children come out of their shells and become more sociable with others. Even if they’re playing in groups of three or four, outdoor learning makes it easier for them to make new friends and talk to different children. This all helps to encourage social skills and how to interact in a responsible way, without constant adult supervision. Outdoor learning is one of the ideal ways to help children develop their creative skills. From making up stories about the world around them to creating new ways for using the natural environment, there’s plenty for them to do. Away from the constraints of indoor learning, they are able to tap into their creative ‘wells’ and learn in new and exciting ways. Connecting indoor and outdoor learning When children are given the chance to learn in a new environment, they will subconsciously understand the lessons they’ve already been through in the classroom, with the tasks they’ve set themselves outside. From basic maths skills (adding up a number of stones in a pile) to story time (creating tales about their surroundings), learning outdoors gives them a chance to understand practical lessons, in a new and exciting environment. How else will they benefit from outdoor learning? A high-quality outdoor learning experience can also help children to: - Develop their inquisitive thinking skills, as well as problem-solving techniques based on ‘real’ situations - Develop the ability to adapt to certain situations or challenges that they wouldn’t face in the classroom - Let children identify and manage smaller hazards and risks associated with outdoor play - Develop collaborative-working and communication skills - A guide to the Montessori teaching style - Five tips to help introverted students - Advice for first-time teaching assistants In summary, outdoor learning and development can help children understand the natural world, and enhance the skills that they have before moving on to the next stage of their education. It’s essential that they have the opportunity to enjoy everything the outdoors has to offer, and have the chance to grow in a rich, learning environment. They’re able to discover new skills, and play with others in a place that’s open, freeing and full of natural curiosities. What do you think? Is this something that you’ve seen in your working life? Would you do anything differently? We’d love to hear your thoughts, so make sure you let us know in the comments below. Likewise, if you would like the opportunity to help children in their own education, take a look at the range of jobs we currently have available on our job board.
This lesson plan is designed to be used in conjunction with the film Sierra Leone's Refugee All Stars, the story of a band born in a West African refugee camp that chooses to fight back against their suffering and circumstances with music. Note: A significant portion of the film has subtitles. In addition, the film includes graphic war images and accounts of atrocities. Please preview the film before showing it in its entirety in a classroom setting. POV documentaries can be recorded off-the-air and used for educational purposes for up to one year from the initial broadcast. In addition, POV offers a lending library of DVDs that you can borrow anytime during the school year -- FOR FREE! By the end of this lesson, students will: - Analyze a song about the recent civil war in Sierra Leone. - Discuss the role of social protest music. - Write new lyrics to an existing song to address a current social issue. - Present their own protest songs to classmates. SUBJECT AREAS: Geography, World History, Music - Political map of Africa Viewing Guide and Song Analysis (PDF file) - Method (varies by school) of showing the class a video clip from the POV website for Sierra Leone's Refugee All Stars, or a copy of the film and a VHS/DVD player and monitor - One or two examples of other protest songs. A good source of ideas is the Independent Lens protest song feature, Strange Fruit ESTIMATED TIME NEEDED: Two 50-minute class periods, plus homework Performance of Weapon Conflict in Sembakounya Refugee Camp (2:49 minutes) The clip begins at 3:15 with text on the screen: "Sembakounya Refugee Camp, Republic of Guinea." It ends at 6:04 with the performance of "Weapon Conflict." Created in the late 18th century by freed slaves from the British colonies in the West Indies, Sierra Leone gained independence in 1961. From 1991 to 2002, a brutal civil war displaced more than 2 million people (about a third of the population), caused at least 50,000 deaths and brought about the mutilation of an estimated 100,000 men, women and children. Hundreds of thousands of civilians from Sierra Leone, including those who formed the band Sierra Leone's Refugee All Stars, found refuge in the neighboring country of Guinea, primarily in camps run by the United Nations High Commission for Refugees (UNHCR). Once peace was reestablished in Sierra Leone, the UNHCR began actively repatriating Sierra Leoneans from the camps. By mid-2004 the UNHCR reported that fewer than 2,000 Sierra Leonean refugees remained in Guinea. Those who chose to stay will be integrated into Guinean society and will no longer receive UNHCR aid. 1. To set the stage for the lesson, have the music of the band Sierra Leone's Refugee All Stars playing in the background as the students enter the classroom. If you go to the filmmaker's website, you can find mp3 clips of the band's music, or, alternately, you can buy the CD from the band's website or download their songs from an online music provider. 2. Show students the location of Sierra Leone and Guinea on a map of Africa. Explain that from 1991 to 2002, Sierra Leone was devastated by civil war. Civilians were the victims of brutal murders, mutilations and other atrocities committed by soldiers on both sides of the war. To escape the violence, hundreds of thousands of Sierra Leoneans fled to the neighboring country of Guinea, where they lived for years in United Nations refugee camps. 3. Pass out the lesson handout (PDF) and explain that while in a refugee camp, a number of musicians came together to fight back against their circumstances using their music. Tell students the musicians formed a band called Sierra Leone's Refugee All Stars, and the class is going to watch as they sing their song Weapon Conflict. Go over the questions on the handout to help focus student viewing and then show the clip (length: 2:49 minutes). 4. Use the handout to analyze the song as a class. As part of the discussion, explain that while living in refugee camps, the band was able to visit several other camps to perform their music. Ask students how the band's music might have helped them and other refugees cope with their circumstances (for example, did it provide a place of refuge and escape from everyday realities, give them a source of power, provide a sense of purpose, build unity among refugees, raise awareness of their situation, help refugees deal with loss?) 5. Discuss the role of protest music and provide an example or two of other protest songs that students might be more familiar with. Use the questions from the handout to examine the content of these other examples. 6. For homework, challenge students to identify a social issue of importance to them, research it and then write their own protest-song lyrics to a tune of their choice. For example, students could address concerns about an environmental issue with original lyrics set to the tune of "Twinkle, Twinkle, Little Star." Or students could choose a favorite pop song to which they could match their lyrics. Encourage them to be creative! 7. Allow time for students' presentations of their original protest songs. Consider asking for volunteers to perform for the class, or break students into smaller groups to share their work. Then have students submit their lyrics sheets. (Be sure students indicate on their lyrics sheets the tune to which the lyrics are set.) Students can be assessed on: - Analysis provided on the Viewing Guide and Song Analysis handout - Contributions in discussions - Understanding of current social issues as demonstrated in their original song lyrics - Presentations of their protest songs EXTENSIONS & ADAPTATIONS - Have students match images to their protest songs in a musical slideshow. - The POV website features additional scenes with Sierra Leone's Refugee All Stars taped after the film was completed. Explain that after the civil war ended, the band members returned to Sierra Leone and recorded their music. They have gone on tour, performed their music, appeared on The Oprah Winfrey Show, worked with bands like Aerosmith and U2 to record new music and much more. Students can watch exclusive video on the POV website to find out more about life on the road with the band and write news stories describing their activities. - Put together a class film festival featuring African issues. In addition to Sierra Leone's Refugee All Stars, POV has also featured Rain in a Dry Land (Somalian refugees resettling in the U.S.), Lumo (a young woman recovering from a violent attack in the Democratic Republic of the Congo) and Lost Boys of Sudan (a group of Sudanese "lost boys" are resettled in the United States). Other films on African issues include FRONTLINE/World's Sierra Leone: Gunrunners or Sudan: The Quick and the Terrible, plus Wide Angle's Democracy in the Rough (Democratic Republic of the Congo), Ladies First (Rwanda), and AIDS Warriors (Angola). After watching the films, have students compare and contrast the situations in each country and the perspectives that were shared. - Use the lesson's analysis of the song Weapon Conflict to introduce the memoir, A Long Way Gone, by Ishmael Beah. This account from a former child soldier in Sierra Leone's civil war describes how the war came to the author's community, how he got involved in the fighting and how he was later able to be rehabilitated and rejoin civilian life. The website for this book features video clips of the author and an excerpt from the book. Have students determine how and why the civil war began, how the conflict evolved over time and how it changed Sierra Leonean culture. Also, explore the methodology used by soldiers to recruit children to fight in the war. Point out that 300,000 child soldiers are estimated to be fighting in more than 50 conflicts worldwide. - Learn more about refugees by visiting ninemillion.org, a site that features the song Living Like a Refugee by Sierra Leone's Refugee All Stars, includes a map that shows how the plight of refugees is a worldwide problem and provides photos, video clips and essays describing visits to refugee camps. Students could use this information to educate others about refugees, raise funds to donate to organizations that support refugees or inspire creative writing about life in a refugee camp. - Use the lesson's song analysis as a springboard for examining social protest music in U.S. history. The website for Independent Lens' film Strange Fruit provides a timeline of such music from 1776 to the present and includes lyrics, music clips and historical context. - Watch the entire film, Sierra Leone's Refugee All Stars (Due to some graphic war images and accounts of atrocities, be sure to preview before classroom use). Discuss life in a refugee camp, how such camps are funded and the services provided by the United Nations. The website for this public-radio series introduces people to a wide range of world music and includes an interview with Reuben Koroma and a review of the band's CD. The website of a film documenting the 1999 rebel attack in Freetown, Sierra Leone, includes an excellent set of links to sites representing diverse groups as well as general background on the conflict, including information on the diamond trade. A convenient gateway to a broad range of information about Sierra Leone. This Web site provides an account of the Sierra Leonean peace process from the perspective of the United Nations. These standards are drawn from "Content Knowledge," a compilation of content standards and benchmarks for K-12 curriculum by McREL (Mid-continent Research for Education and Learning). Arts and Communication, Standard 3: Uses critical and creative thinking in various arts and communication settings. Level IV, Benchmark 8: Knows ways in which different sources are used to produce art forms. Geography, Standard 9: Understands the nature, distribution and migration of human populations on Earth's surface. Geography, Standard 10: Understands the nature and complexity of Earth's cultural mosaics. Geography, Standard 13: Understands the forces of cooperation and conflict that shape the divisions of Earth's surface. Language Arts, Standard 4: Gathers and uses information for research purposes. Language Arts, Standard 9: Uses viewing skills and strategies to understand and interpret visual media. ABOUT THE AUTHOR Cari Ladd, M.Ed., is an educational writer with a background in broadcast journalism, secondary education and media development. Previously, she served as PBS Interactive's Director of Education, overseeing the development of curricular resources tied to PBS programs, the PBS TeacherSource website (now PBS Teachers), and online teacher professional development services. She has also taught in Maryland and Northern Virginia. Sierra Leone. CIA World Factbook. Updated February 8, 2007. Sierra Leone. UNHCR Country Information. UNHCR.
Fearwhich in humans ranges from generalized anxiety to specific phobiasis an important biological adaptation and a common behavior in all mammals. Fear is an emotion, an unspoken memory, stored in special parts of the brain. It provokes individuals to react rapidly, almost instinctively, in the face of perceived danger. Fear can be present in greater or lesser degrees in different individuals. When a tendency to fear is present in excess, its consequences are not always helpful. As many as one fourth of all Americans will suffer from potentially debilitating anxiety, panic disorders, animal phobias and post-traumatic stress reactions at least once in their lives. These disorders cause not only mental anguish but a variety of real physical symptoms, including localized pain. As with other forms of behavior, we would like to know to what extent fear is learned from environmental experience and to what extent it is influenced by our genetic makeup. Image: BROOKHAVEN NATIONAL LABORATORY The study of fear in animals such as mice has shown that fear can be selectively bred into succeeding generations, suggesting a strong genetic component. Randomly selected mice subjected to an "open-field test"a brightly lit, open box with no hiding placesexhibit a range of different responses. Some mice cower motionless near one wall, defecating and urinating repeatedly, whereas others roam about, sniffing and exploring without concern. Most mice are somewhere between these two extremes. If fearful mice are bred with one another repeatedly over a dozen or so generations, it is possible to develop lines of mice in which all members are highly anxious and fearful in a variety of different tests. But they do not learn this from one another or from their mothers. A newborn mouse from a fearful line, reared by a fearless mother together with fearless siblings, will still be fearful as an adult. Specific genes associated with such behavior are currently being identified in laboratory mice. Not surprisingly, many of the genes associated with fear or the lack of it encode neurotransmitters or their receptors. These are the molecules within the brain responsible for chemical communication between nerve cells; they ultimately underlie all behavior. Mice lacking functional nerve cell receptors for the neurotransmitter GABA (gamma-amino butyric acid) are more fearful than mice with the receptor. GABA is used by higher regions of the brain to tone down some of the lower brain's initial impulses and may function to decrease overly fearful responses to environmental stimuli. Similarly, mice lacking a receptor in the brain for glucocorticoid stress hormones are much less anxious than control mice. An unexpected category of genes associated with fearfulness in mice includes some of the genes involved in the operation of biological clocks. How these genes relate to fear is unclear at present, but unraveling their role may shed new light on the origins of fear within the brains of people as well as mice. There is considerable evidence in humans, derived largely from studies of adopted children, and identical and fraternal twins reared together or apart, that a tendency toward anxiety and fear is a heritable trait. The specific form that fear takesphobias with specific associations, such as snakes, fear of pain, or of heights or closed spacesis almost entirely associated with individual environmental experiences. But the tendency to develop fearful or anxious responses to the environment in general has a clear genetic component. As with mice, it appears that a major portion of the genetic contribution to human fear and anxiety involves neurotransmitters and their receptors, and again GABA and its receptors play a key role. But perhaps the most important neurotransmitter mediating anxiety in humans is serotonin. Variability in the receptors responsible for clearing serotonin from the synaptic space between two communicating neurons correlates quite well with variation in anxiety among different individuals. Anxiety is closely connected with depression in humans, and drugs that modulate serotonin levels in neuronal synapses also affect both depression and anxiety. Serious depression also has a marked genetic component. Fear and anxiety are influenced by many genes; there is no such thing as a simple "fear" gene that is inherited from one generation to the next. The genes controlling neurotransmitters and their receptors are all present in several different forms in the general population. The particular combinations of these different forms that we receive from our parents will predispose us to respond with greater or lesser degrees of anxiety to events in our environment. But the degree to which our lives are affected by this inherited predisposition will depend to a very large extent on our individual histories--the number, strength, type and duration of events that elicit such reactions in the first place.
Masonry can be used in a wide variety of architectural applications, including • Walls (bearing, shear, structural, decorative, bas-relief, mosaic) • Arches, domes, and vaults • Beams and columns Masonry, while often simple and elegant in form, can be complex in behavior. Also, unlike concrete, it cannot be ordered by the cubic yard. To understand its behavior, and to be able to specify masonry correctly, we must examine each of its basic components: units; mortar; grout; and accessory materials. Immediately below, each component (and related concepts) is discussed briefly. In later sections, more details are provided. Preliminary Discussion of Masonry Units Masonry units, as noted in Table 2.1, can be classified in a wide variety of ways. In this book, we shall emphasize the behavior and use of structural masonry units, of fired clay or of concrete. Preliminary Discussion of Masonry Mortar In the United States, three basic cementitious systems are used for mortar: cement-lime mortar; masonry-cement mortar; and mortar-cement mortar. The first two are widely used, the third has been recently introduced. Cement-lime mortar is made from different proportions of portland cement or other cements, hydrated masons’ lime, and masonry sand, mixed with water. It can be batched by hand on-site using material from bags, or batched automatically on-site using material from silos. Masonry-cement mortar is made from different proportions of masonry cement and sand, mixed with water. It may also contain additional portland cement or other cements. Masonry-cement formulations and manufacturing processes are manufacturer-specific. Ingredients are not required to be identified, and usually are not. Masonry cement generally consists of portland cement, pozzolanic cement, or slag cement, plasticizing additives, air-entraining additives, water-retention additives, and finely ground limestone (added primarily as a filler, but with some plasticizing and cementitious effect). Mortar-cement mortar is made from different proportions of mortar cement and sand, mixed with water. It may also contain additional portland cement or other cements. Mortar cement formulations and manufacturing processes are manufacturer-specific. Ingredients are not required to be identified, and usually are not. Mortar cement generally consists of portland cement, pozzolanic cement, or slag cement, plasticizing additives, air-entraining additives, water-retention additives, and finely ground limestone (added primarily as a filler, but with some plasticizing and cementitious effect). It differs from masonry cement in that it is formulated specifically for tensile bond strength comparable to that of cement-lime mortar. Preliminary Discussion of Masonry Grout Grout is fluid concrete, usually with pea-gravel aggregate. It can be used to fill some or all cells in hollow units, or between wythes. Preliminary Discussion of Masonry Accessory Materials Masonry accessory materials include reinforcement, connectors, sealants, flashing, coatings, and vapor barriers. • Connectors (of galvanized or stainless steel) connect a masonry wall to another wall, or a masonry wall to a frame, or a masonry wall to something else. • Sealants are used in expansion joints (clay masonry), control joints (concrete masonry), and construction joints. • Flashing is a flexible waterproof membrane used for drainage walls. • Coatings include paints and clear water-repellent coatings. • Moisture barriers and vapor barriers are used as parts of wall systems to retard the passage of water in liquid form and vapor form, respectively. Preliminary Discussion of Masonry Dimensions Masonry unit dimensions are typically described in terms of thickness × height × length. Typically, the length is the largest dimension, the thickness is next, and the height is the smallest dimension. For example, a typical clay masonry unit has dimensions of 4 × 2.67 × 8 in. These are nominal dimensions, that is, the distances occupied by the unit plus one-half a joint width on each side. Joints are normally 3/8-in. thick. The specified dimensions of the unit themselves are smaller; in this case, 3-5/8 × 2-1/4 × 7-5/8 in. The actual dimensions are the measured size, and should fall within the specified dimensions, plus or minus the tolerance permitted by the governing material specification. The sides of a masonry unit are often designated in literature by special names • The bed is the side formed by thickness × length • The face is the side formed by height × length • The head is the side formed by thickness × height Orientation of Masonry Units in an Element Masonry units can be placed in a wall or other element in many orientations, as shown in Fig. 2.1 (looking perpendicular to the plane of the element). The stretcher orientation is the most common, and the soldier orientation is often used above or below wall openings. Masonry units can be placed in a wall or other element in many bond patterns (arrangements), as shown in Fig. 2.2 (again, looking perpendicular to the plane of the element). In this figure, the horizontal joints are referred to as bed joints, and the vertical joints are referred to head joints. In all the bond patterns of this figure, the bed joints are continuous along every course (level) of masonry. • In running bond, the head joints align in alternate courses, and are aligned with the middle of the units in adjacent courses. • In stack bond, the head joints align in adjacent courses. • In 1/3 running bond, the head joints align in alternate courses, and are aligned one-third of the way along the units in adjacent courses. • In Flemish bond, units of two different lengths are used. Many other bond patterns are possible. Types of Walls Masonry is most commonly used in walls. Masonry walls can be classified in many different ways. For now, we shall classify masonry walls according to how they resist water penetration. Using this criterion, masonry walls can be classified as barrier walls or drainage walls. Examples of each type are shown in Fig. 2.3. • Barrier walls resist water penetration primarily by virtue of their thickness. They may have coatings. They may be single-wythe (one thickness of masonry), or multiwythe. Multiwythe barrier walls can have the wythes connected by bonded headers [masonry units placed in header orientation, or by a filled collar joint (space between wythes)]. • Drainage walls resist water penetration by a combination of thickness and drainage details. Drainage walls may also have coatings. Drainage details include an airspace (at least 2 in. wide), flashing, and weepholes. Drainage walls can be single-wythe (veneer over steel studs) or multiwythe (veneer over masonry backup). The latter are often also called “cavity walls.” Overview of How Masonry Is Specified To further discuss how masonry is specified, it is necessary to recognize the following: 1. Unlike the steel or concrete industries, individual segments of the masonry industry rarely produce a finished masonry assembly. 2. It is therefore necessary to specify precisely each component of masonry (units, mortar, grout, accessory materials). In the United States, this is done through standard specifications, methods of sampling and testing, test methods, and practices. Most applicable standards are developed by the American Society for Testing and Materials (ASTM). A few are produced by model code organizations (e.g., the International Code Council). We will focus on ASTM standards, using them as a frame of reference for the specification of masonry elements.
Subterranean termites have a cryptobiotic or “hidden” lifestyle. This means that they are always hidden from our view either beneath the surface of the soil, beneath the surface of the wood, or in their mud tunnels. This cryptobiotic nature contributes to their success in invading human structures. The termites enter our buildings from beneath the soil surface and forage within the wood. We usually do not detect their presence until damage becomes evident or termite swarming takes place. Often we have no idea how the termites got into our home. This can make it very difficult to control them. The following are descriptions of how termites typically invade structures, building practices that encourage termite attack, and how you can detect the signs of termite infestation. Usual Point of Entry Subterranean termites usually invade a structure from the soil along the foundation. They commonly enter through cracks in the slab, utility conduits, expansion joints, and plumbing connections. A common problem in Virginia is subterranean termites entering a structure between the foundation and brick veneer, stucco or expandable foam insulation (EFIS) that is below the grade level. This is a major problem because there is no external evidence of the termite presence until the damage becomes obvious. Also, wood structures in direct contact with the ground such as decks or porches invite termite entrance. The source of most of subterranean termite infestations is a colony living in the soil. However, some infestations originate from above ground (aerial infestations). Above ground infestations occur either when a termite king and queen begin a new nest within a structure or when foraging termite workers become isolated indoors and cannot return to the parent colony. Such infestations are rare in most of Virginia because they require extremely moist conditions year round. However, homes with flat roofs or chronic leaks are sometimes at risk because enough moisture is retained within the structure to allow the termites to become established. The constant moisture allows the termite colony to survive with no connection to the soil. In such cases the structural moisture problems may be as damaging to the home as the termite activity. Indicators of Infestation A subterranean termite infestation is usually recognized by the following 3 indicators: Mud tubes. The termite foraging tubes extend from the ground to the infested wood. The tubes provide shelter for the foraging termites. The tubes are flattened and muddy looking in appearance. Most are about the width of a pencil. They are most obvious when they extend over concrete foundations and other exposed surfaces. However, the tubes are often less visible, running along cracks, underneath flooring, or behind siding and baseboards. Swarmers. Winged termites emerging indoors or outside from swarming tubes immediately adjacent to the structure are often the first sign of a subterranean infestation. Swarming termites are attracted to light. Therefore, swarmers indoors are often found around lighting fixtures, windows, doors and vents. Also, large numbers of discarded termite wings on windowsills, floors or in spider webs are a sure sign of infestation. Wood damage. A common indication of subterranean infestation is the presence of dark areas or blisters in wood flooring. However, subterranean termite damage can go unnoticed because the termites only eat the spring wood leaving the grain and exterior surface intact. However, the galleries can be detected by tapping the wood every few inches with the handle of a screwdriver. The damaged wood sounds hollow and the screwdriver may even break through the wood into the galleries. If the galleries are active the worker termites will be observed inside. Problematic Construction Practices Several common construction practices contribute to subterranean termite infestation either by providing the termites with access into the structure or by creating moisture conditions ideal for termite colonization. The following are examples of construction and landscape practices that lead to subterranean termite infestation: - Wood to soil contact. Provides termites with a direct highway from the colony in the soil to the structural wood. - Form boards not removed after construction. Form boards, grade stakes, tub trap boxes, and spacers left in the slab allow termites to eat their way into the structure. - Wooden debris left inside CMUs. Filling the cavities in concrete masonry units with wood scraps allows termites to forage through the concrete voids. - Wood refuse buried under the slab or stoop. Burying construction debris under a porch, stoop or slab causes large numbers of termites to congregate directly adjacent or under the structure. - Stucco below grade. Stucco, brick veneer or EFIS below grade provide the termites with hidden access into the structure. The infestation will typically go undiscovered until damage becomes obvious. - Improper drainage. Some structures are built in a depression. Others may have insufficiently extended eaves, or have short downspouts. These characteristics will result in moisture accumulation at the base of the foundation. This moisture provides an ideal habitat for subterranean termites. - Landscaping. Landscaping, including the spreading of mulch or gravel against the foundation, causes moisture to be retained at the base of the structure. Because moist soil is prime termite habitat, the area immediately adjacent to the foundation should be kept as dry as possible so that termites will prefer to live and forage elsewhere. In the United States subterranean termite infestation amounts to billions of dollars in damage each year. It is therefore very important to have your home thoroughly inspected for termite activity if you observe any of the signs of infestation. Also, when purchasing a home most mortgage companies will require a Wood Destroying Organism (WDO) inspection and a written report indicating any termite activity or damage. Be sure to have the home inspected by a pest control operator who has been certified by the Virginia Pest Management Association (VPMA) for WDO inspections. Also, schedule the inspection for a time when you can be present. This way you can have the operator point out conditions around your home that are conducive to termite infestation and tell you how to correct them. - Potter, M. F. Termites, pp. 232-333. In S. A Hedges and D. Moreland [eds.], Mallis Handbook of Pest Control, eighth edition. Mallis Handbook and Technical Training Company. 1997. - Koehler, P. G., D. E. Short, and W. H. Kern. Pests In and Around the Florida Home. University of Florida Cooperative Extension Service, IFAS No. SP 134. Gainesville FL. 1998. Virginia Cooperative Extension materials are available for public use, reprint, or citation without further permission, provided the use includes credit to the author and to Virginia Cooperative Extension, Virginia Tech, and Virginia State University. Issued in furtherance of Cooperative Extension work, Virginia Polytechnic Institute and State University, Virginia State University, and the U.S. Department of Agriculture cooperating. Edwin J. Jones, Director, Virginia Cooperative Extension, Virginia Tech, Blacksburg; M. Ray McKinnie, Administrator, 1890 Extension Program, Virginia State University, Petersburg. March 1, 2010
In the last few years, habitat destruction, wildlife trade, pollution, disease and climate change have been some of the greatest threats to the survival of wildlife. Currently, there are over 32,000 species on the International Union for Conservation of Nature (IUCN) Red List whose very existence is threatened But all hope is not lost. Conservation efforts in the past have managed to achieve some pretty incredible things, including bringing back animal and bird species from near extinction. Here are 5 that made an amazing comeback: The panda has become the poster child for wildlife conservation. In 1980s excessive poaching and deforestation brought the panda population down to just a few hundreds. With millions of dollars being spent on habitat restoration, captive breeding and protection enforcement, the panda population is now more than 2000 strong! 2. Sea otter: Sea otters too faced a period of near extinction after their numbers dropped to a mere 2,000 in 1911. This was primarily because they were trapped and killed for their luxurious fur. But after noticing their rapidly declining population, the International Fur Seal Treaty was signed in 1911, between US, Russia, Japan, and Great Britain, to ban large scale commercial hunting of sea otters and to allow their population to recover. Their global population now consists of just over 100,000 otters. 3. American Alligator The American alligator population reached an all-time low in the 1950s and it was thought that their population would never recover due to unchecked hunting and habitat destruction. They were listed under the Endangered Species Act and after years and years of tireless work to preserve their habitat and ensure their protection, they were finally taken off the list in 1987 and are now thriving. Often considered nature’s finest flying machine, it wasn’t always blue skies and sunshine for the Peregrine falcon. Peregrine populations were in steep decline during the mid-20th century, and in the United States, these beautiful birds became an endangered species. Loss of habitat, shootings, egg collecting, and other human disturbances had weakened their populations for decades, but drastic declines didn’t occur until after the widespread use of a popular insecticide—DDT, used to control agricultural pests and malaria-carrying mosquitoes. By the mid-1960s, there were no peregrines in the eastern United States and by the mid-70s western populations had declined by up to 90 percent. Thankfully DDT was banned by 1972, and gradually the falcon population rose. By 1999, they were off the endangered species list and soaring again. The Schaus Swallowtail Butterfly, which graced a stamp in 1996 to reflect its endangered status, is one of the rarest butterfly species and isn’t easy to locate. Over the years, habitat loss, drought, pesticides have contributed to a drop in sightings from 41 in 2011 to four in 2012. Efforts were made to protect their habitat and thanks to the captive breeding program undertaken by the University of Florida, 50 butterflies and 200 caterpillars were released into the wild. By 2016, there were hundreds of them, increasing hope for their survival These are big wins for the planet and it’s important that we keep fighting hard for all creatures that don’t have a voice of their own. After all, this is their planet too.
Unlocking the secrets of plant genomes in high resolution Resolving genomes, particularly plant genomes, is a very complex and error-prone task. This is because there are several copies of all of the chromosomes and they are very alike. A team of bioinformatics researchers from Heinrich Heine University Düsseldorf (HHU) has now developed a software tool that allows for precise assignment to the correct copies - a process known as 'phasing'. They present their development in the latest online edition of the journal Genome Biology. The genomes of all higher life forms are stored in the cell nucleus on chromosomes. Chromosomes are composed of strands of the DNA molecule. The genetic information itself is encoded in a sequence of adjacent base pairs of the molecules adenine (A), cytosine (C), guanine (G) and thymine (T). Different species have different numbers of chromosomes; for example, humans have 23, while potatoes have 12 and wheat has 7. In addition, there are different copies or 'haplotypes' of the chromosomes. Humans have two copies, one from the mother and one from the father, while potatoes have four and wheat even has six. Species with two copies are referred to as 'diploid', whereas those with more than two are 'polyploid'. The copies are almost identical, with 'almost' being the operative word. It is the differences between them that determine the variability of the organisms within a population. In order to unlock the genetic information, the researchers tackled something akin to a large jigsaw: They took a larger number of cells, divided the cells' genomes into lots of small parts—called 'reads' - and sequenced the information contained in those parts. This was necessary because the technology currently available can only process small sections of DNA. The result was a huge volume of data—billions of reads, with a data volume of several hundred gigabytes. They comprise sequences of differing lengths made up of the letters A, C, G and T. The next task for the bioinformatics researchers was to determine their position within a chromosome, then assign the corresponding sections to a chromosome (a process known as 'mapping') and finally to find the right copies of the chromosome. This last stage is known as 'phasing'. The task is made more difficult by sequencing errors. There are good, efficient tools available for mapping. However, the bioinformatics tools needed for phasing are still in their infancy. This was precisely where the team of bioinformatics researchers from HHU focused their attention. In a joint project funded by the German Research Foundation and managed by Prof. Dr. Gunnar Klau (Algorithmic Bioinformatics working group) and Prof. Dr. Tobias Marschall (Institute of Medical Biometry and Bioinformatics, University Hospital Düsseldorf) in collaboration with Prof. Dr. Björn Usadel (Institute of Biological Data Science), they developed a software tool named 'WhatsHap polyphase' and tested the tool successfully using model data as well as the potato genome. This new tool solves the problem using a two-phase process. The first phase involves clustering the reads, i.e. splitting them into groups. Reads in one group probably come from one haplotype or a region of identical haplotypes. The second phase involves 'threading' the haplotypes through the clusters. During threading, the reads are assigned to the haplotypes as evenly as possible, ensuring as little as possible jumping back and forth between clusters. The new tool has been added to the main 'WhatsHap' package, which is freely available. The package has already been used to carry out the phasing successfully for diploid chromosome sets, e.g. for humans. This new addition from the team based in Düsseldorf means that phasing is now also possible for polyploid organisms. Prof. Klau said: "Our new technology allows for plant genomes to be phased in high resolution and with a low margin of error".
Before we can or should characterize a student writer as “struggling,” it is essential to consider what steps have been already taken to develop and support the writer. When we think about response to intervention models, considering the instruction provided for the student is key. Students should not be labeled if their weaknesses resulted from deficits in instruction. Therefore, the type of writing instruction provided in the regular classroom should be evaluated. But what does quality writing instruction look like in the regular classroom environment? The following questions are important to consider when evaluating classroom writing instruction. - How often are students provided with opportunities to write? Are students writing daily? Weekly? Rarely? Only for assessment purposes? Is there a culture of writing in the classroom or is writing just an item to be checked off in a daily lesson plan? - What types of writing are encouraged? Are students limited to short responses to their reading? Do they just write to complete worksheets and to answer questions? Are they encouraged to write in a variety of genres? Do they produce only formulaic pieces? How much choice is offered? - Are students engaged in writing across the curriculum? Is writing separated from all areas of the curriculum or is it integrated through the school day? - How are students provided with feedback about their writing? Do students have opportunities to confer with the teacher about their writing? What do conferences look like? How does the teacher approach conferences with student-writers? Does the teacher provide written feedback? Verbal feedback? A combination of written and verbal feedback? - Does the teacher provide whole-group instruction? Small-group instruction? Mini lessons? Does the teacher provide a combination of these instructional formats? - What does the writing process look like in the classroom? How are students guided through this process? What types of support are available to students? Are students provided with modeling and guided practice? - Do students have the opportunity to share their work with others? What opportunities are provided for this purpose? Are these opportunities limited to the classroom? - How is technology incorporated into writing instruction and activities? What tools are available for teachers and students? - Has the teacher been provided with ample opportunities for professional development in the area of writing? Does the teacher take advantage of these opportunities? - Is the teacher a writer? This statement doesn’t mean that the teacher has to be a formally published author or have certain credentials, but teachers who write serve as powerful models for their students by not only writing with their students, but also through sharing their writing. They can “practice what they preach.” The answers to these questions can stimulate conversations and encourage an honest assessment of classroom writing instruction. We have to provide students with the best environment in order for them to grow as writers. Our students deserve nothing less. Writing is a topic that either instills joy or fear in teachers. For some educators, teaching writing may feel like a daunting task. The awareness of the importance of writing is often tempered by feelings of inadequacy. How do you teach writing? Which methods or approaches are the best to use with students? How do you teach writing if you do not consider yourself to be a writer? For most of my life, I’ve described myself as a writer. In the second grade, I entered the PTA Reflections contest and won an honorable mention for a piece of writing. My dream was to be a published author. During elementary and middle school, I filled up notebook after notebook with stories. There was a blip from high school to my mid-twenties when I didn’t write, but that’s a story for another time. However, when I first started teaching, I knew little, if anything, about providing writing instruction for students. As a teacher working with students who struggled with literacy, many of my students found writing to be a challenge. I knew my personal history as a writer, but I didn’t know what to do to not only encourage my students to see themselves as writers, but also to develop their skills and strategies. I also discovered that some of my “struggling readers” had amazing ideas and grasped storytelling, but their limited ability with the mechanical aspects of writing often meant that their thoughts were lost in a maze of grammatical and spelling errors. Handwriting issues also affected their messages. Those children had so much to share, but didn’t have the tools to do so. When provided with opportunities to push into classrooms, I recognized that the struggling readers in my intervention groups were not the only ones who found writing challenging. Students described as “average” or “above average” were not always comfortable with writing. Their writing sometimes mirrored that of the students in my intervention groups and they needed additional support. While these students do not need to participate in reading interventions, they do need writing. Thankfully, my master’s and doctoral programs did address writing. I discovered research by Steve Graham, Karen Harris, and others. I also discovered online communities that supported and enhanced my writing professional development (twowritingteachers.org, teachwrite.org). I look forward to sharing this information in future posts! Providing quality instruction is a basic tenet of response to intervention. This emphasis, however, may not always include or address the type of writing instruction provided for all students. We need to examine writing instruction in addition to reading instruction to ensure that all students receive quality writing instruction. Therefore, teachers should be provided with opportunities for professional development that reflects best practices in writing. Administrators, reading specialists, and coaches at the building and division levels can provide support for classroom teachers to ensure that all student writers benefit from exemplary instruction. I look forward to sharing information and ideas about how we can all collaborate to create environments where our student-writers can thrive.

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