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Imagine yourself standing under a train trestle, and a train passes overhead. You feel the vibrations in your feet as it approaches, reaching out with your arm you grab the support to assure your footing. Your eardrums ring with the screeching sound of metal scraping metal, the clang of each car passing jars your body. Finally, it passes but there is a lag in your senses, an echo of the train, as your body starts to recover. Now imagine living under that trestle. Would you be able to hear noises that could alert you to danger? Could you have successful communication with another person without confusion? Would you just “get used to it,” as if the trains didn’t exist? Are you able to move away from the tracks, and how far away from the tracks do you have to be for the trains to no longer have an effect or be a distraction? Now replace the tracks with the surface of a body of water, the train with a boat motor, and you with a fish. Hearing is very important to the survival and fitness of most fishes. It plays an important role in the detection, reaction, and evasion of predators. Hearing is also important to most fish in the role of prey detection and capture. In some species, the sense of hearing is used to detect receptive spawning partners. So, the question of can fish hear in a noisy environment, is an important one. By analyzing the processes in which fish hear, defining what noise is to a fish, and comparing relative data involving the effects of noise on fish in a lab environment, we can develop a better understanding of how noise could be affecting fish in their natural environment. Hearing is the faculty of perceiving sound. The perception of sound to a fish occurs by the stimulation of sensory hair cells. Fish have sensory hair cells located in the inner ear and their lateral line pores. The sensory hair cells detect the oscillation of pressure through water. These sensory cells are part of the acoustico-lateralis system. When oscillation occurs, it stimulates the sensory hair cell sending a neural transmission to the brain to be processed. The detection of oscillation, stimulation of the sensory hair cells, and processing of the neural transmission in the brain is hearing for a fish (University of Maryland, 2003). Noise is irregular fluctuations of sounds that accompany a transmitted electrical signal but are not part of it and tend to obscure it. So noise is a masking agent where the detection of one signal is impaired by another, and covers up relevant sounds or distracts or disrupts the hearing processes of the intended recipient. The frequency of sound that a hearing generalist fish, such as the pumpkinseed sunfish Lepomis gibbosus, can hear is between 100-4000 Hz, so noise to pumpkinseed sunfish would have to fall in that range (Wysocki & Ladich, 2005). The sound frequency range of most freshwater boat motors is between 1000-5000 Hz, and would be considered as noise to many fish. Studies have demonstrated that sunfish are substantially less affected by the same amount of background noise (because of their lower hearing sensitivity) than goldfish Carassius auratus, although there is only a small difference in the threshold to noise ratio of these two species (Wysocki & Ladich, 2005). © Association for Research in Otolaryngology 2005 Audiograms (solid lines) and appropriate cepstrum-smoothed noise spectra (dashed lines) of A. Carassius auratus, B. Platydoras costatus and C. Lepomis gibbosus. –○– Hearing thresholds obtained under normal laboratory conditions, –▵– hearing thresholds under masking noise of 110 dB, –▿– hearing thresholds under masking noise of 130 dB. At a masking noise level of 110 dB LLeq, the mean hearing thresholds (average of all individuals at a particular frequency) of C. auratus increased by up to 20 dB and by up to 44 dB at a noise level of 130 dB (Fig. 2A). The amount of threshold shift differed between frequencies, being more pronounced in the most sensitive hearing range (500 and 1 kHz). At 130 dB, the whole audiogram became relatively flat. Paired t-tests showed significant differences between baseline and masked thresholds for both noise levels at all frequencies except 4 kHz (Fig. 3A), (Wysocki & Ladich, 2005). One challenge that noise can present to certain fish is the reduction of predator detection, evasion, and avoidance. This reduction puts the fish under more stress and could even lead to greater mortality rates in a certain species, if the noise has a greater effect on that species than that of its predators. Another challenge in living in a noisy environment is the affects on prey detection and capture rates of predator species. If noise decreases the amount of successful detections and capture rates of prey this could lead to slower growth and development, elevated stress, reduced fitness, and increased mortality rates (Slabbekoorn et al. 2010). Fitness can be reduced as a result of impacts on reproductive success, arising from incorrect assessment of the quality of rivals or the receptiveness of potential mates (Radford et al. 2014). Loss of energy gains by noise avoidance can have effects on survival and fitness as well. The simplest method of avoiding the potential impacts of anthropogenic noise is to move away from the source. However, this is not always possible if the source dominates certain frequencies, as is the case with low-frequency boat motor noise, or if an entire area is affected, as might occur in certain lakes and estuaries subjected to large amounts of commercial and recreational activities. Also, if a species is dependent on a particular area because of crucial resources, such as food or nesting sites, or is restricted by the geography of the region, then there may be no option but to remain despite the noise (Radford et al. 2014). We know that fish can still hear in certain noisy environments, and that these noises are masking agents that can directly affect fish health and fitness, but there is still a lot we do not know. Some of these issues are, the direct effect on fish communities and how noise might affect individual species ability for adaptation. More research is needed to discover the entire direct effects of noisy environments on fish. Radford, Andrew N., Kerridge E., Simpson, S.D.; Acoustic communication in a noisy world: can fish compete with anthropogenic noise?. Behav Ecol 2014; 25 (5): 1022-1030. doi: 10.1093/beheco/aru029 Slabbekoorn, Hans., Bouton N., Opzeeland I., Coers , A., Carel C., Popper A. N. A noisy spring: the impact of globally rising underwater sound levels on fish DOI: http://dx.doi.org/10.1016/j.tree.2010.04.05 University of Maryland, College Park. "Loud Noise Can Injure Fish Hearing." ScienceDaily. ScienceDaily, 10 February 2003. Wysocki, L. E., & Ladich, F. (2005). Hearing in Fishes under Noise Conditions. JARO: Journal of the Association for Research in Otolaryngology, 6(1), 28–36. http://doi.org/10.1007/s10162-004-4043-4
We now have quite a few different forms of energy–translational kinetic as well as rotational, thermal, bond, gravitational potential and spring (or elastic) potential energy. A given physical situation could involve any number of these. Energy can be transferred among physical systems either as heat (when there is a temperature difference between two objects) or as work (when one object exerts a force (on another object) that acts through a distance). There are yet other forms of energy that involve electrical interactions, magnetic interactions, and a more general form of the gravitational energy. By treating thermal interactions and mechanical interactions on an equal footing, we can approach realistic situations without having to automatically assume friction or air resistance is negligible. By now you should be very comfortable with the energy-interaction model. When we encounter new “kinds” of energy, it won’t be a “big deal.” We simply add them to our repertoire of energy-systems that might change in any particular interaction. Now we are in a position to delve into particle models of matter. Our goal is to be able to understand, in a general or universal way, as many of the properties of matter as we can. As we do this, we will also make a much more direct connection to thermodynamic concepts you have worked with in chemistry courses. Even as we extend and perfect our energy-interaction model, we recognize that many questions are beyond its reach. For example, our before-and-after approach can’t tell us, “How long did it take an object to fall?” Questions like this involve the dynamics (the details) of interactions. We will spend more time in Part 2 of the course and accompanying course understanding the dynamics of rigid objects. This is fundamentally the relation of force to motion known as Newton’s 2nd law. Using Newton’s laws and kinematics to describe the details of interactions, we can answer questions that are unanswerable using the before-and-after approach. But for right now, we stick to an energy approach and avoid, as much as possible, the details of interactions. - Authors of Phys7A (UC Davis Physics Department)
The activities are as follows: - Teacher Guide - Student activity, Graph Type A, Level 2 - Student activity, Graph Type B, Level 2 - Student activity, Graph Type C, Level 2 - Grading Rubric Animals collect information about each other and the rest of the world using multiple senses, including sight, sound, and smell. They use this information to decide what to eat, where to live, and who to pick as a mate. Choosing a mate is an important decision that requires a lot of information, such as how healthy a potential partner is, and information about their genes. Mate quality can affect how many offspring an animal has and if their genes will get passed on to the next generation. Many male birds have brightly colored feathers that are attractive to females. For example, the peacock has bright and elaborate tail feathers, called ornaments, which are thought to communicate a male’s quality. Besides using their sense of sight to see ornaments, female birds may use their other senses to gather information about potential mates as well. Danielle, a biologist, wanted to figure out if birds use vision and their other senses, such as smell, to determine the quality of potential mates. Danielle decided to research how dark-eyed juncos communicate through their sense of sight and smell. Dark-eyed juncos, a type of sparrow, are not colorful birds like peacocks, but they have bright white feathers in their tails. Male dark-eyed juncos have more tail-white than females. Females may use the amount of white in a male’s tail to determine whether he is a high quality mate. Danielle was also interested in several chemical compounds found in junco preen oil, which birds spread on their feathers. This preen oil contains compounds that give birds their odor. Danielle found that males and females have different odors! Just as males have more white in their tail feathers, they also produce more of a chemical called 2-pentadecanone. Danielle wanted to test whether this chemical might be a signal of mate quality. To test her two alternative hypotheses, Danielle captured male juncos at Mountain Lake Biological Station in Virginia. She measured their amount of tail-white by estimating the proportion of each tail feather that was white, and adding up the values from each feather. She also took preen oil samples and measured the percent of each sample that was made up of 2-pentadecanone. She followed these birds for one breeding season to find out how many offspring they had. If females pick mates based on visual ornaments, then she predicted males with more tail-white would have more offspring. If females pick mates based on smell, then she predicted males with more 2-pentadecanone would have more offspring. Featured scientist: Danielle Whittaker from Michigan State University To learn more about Danielle’s work with juncos, see her blog posts “The sweet smell of (reproductive) success” and “Deciphering avian aromas” on the BEACON website. To learn more about Danielle and her research, check out this episode from the PBS/NOVA webseries “The Secret Life of Scientists and Engineers” where she was featured. There is a scientific paper associated with the data in this Data Nugget. The citation and PDF for the paper is below. Whittaker, D., N.M. Gerlach, H.A. Soinic, M.V. Novotnyc, and E.D. Ketterson (2013) Bird odour predicts reproductive success. Animal Behaviour 86(4): 697-703
On this page, we hope to clear up problems that you might have with fractions and their uses in Algebra. Ratios are continually being utilized in math and make many things much easier to do. Scroll down or use the links below to start understanding ratios better! Advanced ratio problems (inferring) Quiz on Ratios In this section we'll help you understand how to deal with ratios. A fraction is also known as a ratio. For example, 3/4 is also the ratio of 3 to 4. Any statement (or equation) that says two ratios are equal is called a proportion. An important thing to remember when dealing with equal ratios is illustrated below. 3 15 4 * 15 - = -- Cross multiply. 4 20 3 * 20 You can solve for unknowns in proportions by using that process. 4 21 1. Solve: - = -- m 5 Solution: Set the cross products equal. you use ratios to make solving word problems easier. Many times, you are expected to gather information from the problem that is not directly stated in words. Gathering this information is called inferring. This section will help you better understand how to infer information from a word problem and solve using ratios. 1. Problem: The ratio of red marbles to blue marbles is 5 to 7. If there are 156 marbles total, how many red marbles are there? Take the Quiz on ratios. (Very useful to review or to see if you've really got this topic down.) Do it!
Climate Change: A Warming Planet - Grade Level: - Fifth Grade-Eighth Grade - Climate Change, Earth Science, Environment, Physical Science - 45 minutes - Group Size: - Up to 24 (4-8 breakout groups) - National/State Standards: - Standard 6: Students assess the interrelated cycles and forces that shape Earth’s surface, including human interaction with Earth. (ASDOE Elementary Science Standards: Grade 5-8, pp. 42-73) OverviewOur world is always changing. Look out your window long enough and you might see the weather change. Look even longer, and you'll see the seasons change. The Earth's climate is changing, too, but in ways that you can't easily see. Round-n-round the Earth goes, where change may happen nobody knows! This program will help students understand the changes occurring in the Earth’s climate, its impact on local ecosystems and help them discover ways to help. Students will be able to: 1. Understand that gases in the Earth’s atmosphere affect climate. 2. Learn how an increase in temperature can affect humans and ecosystems. The Earth's climate is getting warmer, and the signs are everywhere. As global temperatures continue to rise, we'll see more changes in our climate and our environment. These changes will affect people, animals, and ecosystems in many ways. Less rain can mean less water for some places, while too much rain can cause terrible flooding. More hot days can dry up crops and make people and animals sick. In some places, people will struggle to cope with a changing environment. In other places, people may be able to successfully prepare for these changes. The negative impacts of global climate change will be less severe overall if people reduce the amount of greenhouse gases we're putting into the atmosphere and worse if we continue producing these gases at current or faster rates. 1. Board game 3. Checker cab 4. Playing Cards 5. Energy Stars 6. Power point program Introduce Inquiry Questions? What is global climate change? What is climate? Ask: Have you ever heard the term climate? If so, what’s the difference between weather and climate? Write the term on the board and explain so that students understand its meaning. Explain that weather is what is happening outside at any particular moment in time. It may include daily or even hourly accounts of temperature, rainfall, cloud cover, humidity, and other variables. In contrast, climate is what we might generally expect to happen based on long-term weather patterns. Ask: Have you ever heard the term global climate change? If yes, explain where or how they heard the term? If not, what do you think it means? Write the term on the board and explain how to understand its meaning. Global climate is the average climate over the entire planet. Tell the students the reason scientists are concerned is that Earth's global climate is changing. The planet is warming up fast—faster than at any time scientists know about from their studies of Earth's entire history. Show power point slides of different climate. Watch Video (20mins) Before the video, ask students to look for climate change affects, how we are contributing to the negative impacts of climate change on us, and the relationship between what we are doing. Have students watch the video “Climate Change” After the video, check student’s comprehension by asking the following questions. 1. What is carbon dioxide (CO2)? 2. What does (CO2) have to do with climate? 3. Who is affecting by climate change in the video? 4. What happen when we cut down trees? “Save the Environment” Board Game Divide students into groups. Each group must choose a captain. The captain will be the group speaker. The captain will roll the die first. Whatever number appears on the die, move the checker cab that many boxes. If you land on a green box, your captain will look for that number on the playing cards and read it out loud to the group. The card will indicate whether you collect energy stars or move back. The group should talk about what the captain just read out. If it's something we can do to help save the environment, then collect the number of energy stars as indicated on the playing cards from the teacher. The teacher will be in charge of giving out energy stars. After the student lands on a box give the next student the die to roll. If you move back and land on the green box, you do not read the playing cards. The next student rolls the die. Whichever team gets the most energy stars, wins the game. Once groups have reached the “Finish” box, or if their die number takes them beyond the “Finish” box, the game is over. The purpose of this game is for everyone to understand and learn what was discovered from the playing cards. Have a class discussion about how we are negatively affecting the earth because of climate change. Ask the following questions: 1. In the game, what were three ways that we contribute to climate change? (i.e. leaving lights on; pollution from driving cars; and not recycling.) 2. What can we do to stop global warming? (Responses may include an attempt to reduce how much carbon we emit into the atmosphere, invest in green energy technology, public awareness campaign, etc.) Conclusion with Inquiry Questions What is climate? What is global climate change? Do your part to reduce your carbon footprint. Reduce, reuse, and recycle.
From Ohio History Central Interior of the Governor's office in the Ohio Statehouse, 1907. The Ohio Constitution of 1803 established the Ohio Governor's Office. The National Governor's Association ranks the powers of each state's governor in relation to the state's legislature. The Ohio governor has repeatedly ranked as strong. The National Governor's Association utilizes six categories to determine this ranking: - Tenure: Ohio has two four-year terms with only two consecutive terms permitted: strong. - Appointment power: The governor has appointment power for most offices with legislative approval: strong. - Budget powers: Governor has sole control of making the state’s budget: very strong. - Legislative-budget changing power: Legislature has unlimited power to change governor’s budget: very weak. - Veto power: Ohio’s governor has the line-item veto, and it takes three-fifths of the legislature to overturn a veto: very strong. - Governor’s party’s control of the legislature: moderate. As a result of these powers, Ohio's governor, the National Governor's Association has concluded, is a strong leader who can heavily influence state government. The National Governor's Association's ranking is surprising, considering how weak the governor was when Ohio first became a state. In the Ohio Constitution of 1803, the governor could serve unlimited two-year terms, but he had no veto power. The governor did serve as the commander of the Ohio Militia. With white Ohioans still facing the threat of Native Americans and British soldiers, this power was an extremely important one. The Ohio legislature also approved all of the governor's appointments to state offices. The legislature also was primarily responsible for budget issues. In 1851, Ohioans adopted a new state constitution. The Constitution of 1851 created a more democratic system within the state by extending more power to the eligible voters. Nevertheless, the state legislature still dominated the political apparatus. The governor did not have the right to veto legislative acts. In 1903, Ohio's governor received the veto power. This power was extended to a line-item veto in 1912. Originally, it took two-thirds of the Ohio General Assembly to overturn a veto, but in 1912, it was reduced to three-fifths. The primary reason for this change was the fluctuating control of the Ohio House and Senate by the various political parties. Between 1872 and 1904, control of these two houses changed a total of eighteen times. Each political party desired more control over the governor, especially if the governor belonged to an opposing party. Over the course of the twentieth century, constitutional amendments changed the governor's office in other ways. In 1913, the Ohio General Assembly granted the governor the power to establish the state budget, pending the approval of the legislature. In 1954, a state constitutional amendment extended the governor's term in office from two years to four years but no governor could serve more than two successive terms. In 1992, another constitutional amendment limited Ohio's governor to a total of two four-year terms. Since Ohio became a state in 1803, sixty-three men and one woman have served as the state's governor. All of Ohio's governors have been Caucasian.
Spinal stenosis is a narrowing of the spaces in the spine, or backbone, where the spinal cord is located. It puts pressure on the spinal cord, which in turn causes pain and disruption to some body functions. Because spinal stenosis is usually caused by the degeneration (the breaking down, or deterioration) of bones, disks, and ligaments during the aging process, it mostly affects people over the age of 50. In younger people, the condition is usually a result of a genetic disease that affects bone and muscle development, like scoliosis and Paget's disease. Some people may be born with the defect while others suffer a spinal injury that causes it. Tumors can also lead to spinal stenosis. Some people don't feel the effects of spinal stenosis, but most will experience symptoms like pain or cramping in the legs when walking or standing for long periods of time; numbness, weakness, or tingling in a leg, foot, arm, or hand; and bladder or bowel functioning problems. Symptoms tend to worsen over time. To treat spinal stenosis, a doctor might recommend a variety of medications, physical therapy, and steroid injections; for severe cases, surgery can increase space in the spinal area and relieve pressure. At-home treatments like over-the-counter pain medications, hot or cold packs, and using a cane or walker also might help. With proper treatment and some changes in lifestyle, many people with spinal stenosis can remain active for many years. All A to Z dictionary entries are regularly reviewed by KidsHealth medical experts. \|American Academy of Orthopaedic Surgeons (AAOS) The AAOS provides information for the public on sports safety, and bone, joint, muscle, ligament and tendon injuries or conditions.\| \|National Institutes of Health (NIH) NIH is an Agency under the U.S. Department of Health and Human Services, and offers health information and scientific resources.\| \|American Academy of Pediatrics (AAP) The AAP is committed to the health and well-being of infants, adolescents, and young adults. The website offers news articles and tips on health for families.\| \|Scoliosis Research Society The Scoliosis Research Society's site provides patients and their parents with a better understanding of scoliosis and its diagnosis and management.\| \|Can Scoliosis Affect My Height? Find out what the experts have to say.\| \|Brain and Nervous System If the brain is a central computer that controls all the functions of the body, then the nervous system is like a network that relays messages back and forth to different parts of the body. Find out how they work in this Body Basics article.\| \|Scoliosis: Personal Stories (Video) In this video, two girls who were treated for scoliosis talk about their experiences.\| \|Brain and Nervous System The brain controls everything we do, and is often likened to the central computer within a vast, complicated communication network, working at lightning speed.\| \|Your Brain & Nervous System Your brain is the boss of your body and runs the whole show. Learn more in this article for kids.\| \|Scoliosis: Teens Talk (Video) Two teens talk about what it's like to have scoliosis, and how treatment has helped them look and feel better.\| \|Scoliosis The word scoliosis means a curve in the spine. You may know someone with scoliosis - read our article for kids to find out more.\| \|Scoliosis Some teens have a curve in a place where it doesn't really belong: the spine. Here are the straight facts about scoliosis.\| \|Scoliosis Everyone's spine curves, but some kids have scoliosis, which causes the spine to curve too much. Most cases don't require treatment, but even when they do, kids can usually resume an active life after treatment.\| \|X-Ray Exam: Scoliosis Kids with scoliosis have a spine that curves, like an S or a C. If scoliosis is suspected, a doctor may order X-rays to measure the curvature of the spine.\| \|Word! Scoliosis Scoliosis is an abnormal curve of the spine, also known as the backbone.\| What to expect when coming to Akron Children's For healthcare providers and nurses Residency & Fellowships, Medical Students, Nursing and Allied Health For prospective employees and career-seekers Our online community that provides inspirational stories and helpful information.
In order to improve the health of a diverse U.S. population, it is necessary to educate physicians about pervasive racial and ethnic health disparities and help them develop strategies to deliver quality care to underserved populations. Few existing curricula use evidence-based principles to guide learners in developing meaningful clinical responses to overcome disparities. This article outlines the materials developed by the Society of General Internal Medicine’s (SGIM’s) Disparities Taskforce, which represents a comprehensive curriculum for teaching and evaluating health disparities education. The curriculum incorporates five modules: (1) Disparities Foundations, (2) Teaching Disparities in the Clinical Setting, (3) Disparities Beyond the Clinical Setting, (4) Teaching about Disparities through Community Involvement, and (5) Curriculum Evaluation. - Understand attitudes such as mistrust, subconscious bias and stereotyping that practitioners and patients may bring to a clinical encounter. - Be aware of the existence and magnitude of health disparities. - Acquire skills to communicate and negotiate across cultures. There is an ongoing need for medical institutions to incorporate health disparities education into their curricula. The SGIM Health Disparities Curriculum is designed to aid in that effort and to promote understanding of the health care provider’s role in addressing disparities.
When Thomas Jefferson and the Republicans came to power in 1800, they had a major priority: reverse the Federalist trend of expanding the federal government. In Thomas Jefferson’s first message to Congress, in 1801, Jefferson framed the role of the federal government as only being “charged with the external and mutual relations only of these states.” All other matters were to be left to the states. In 1800, the American federal government was “small even by eighteenth-century European standards.” Gordon Wood, Empire of Liberty, 291. Gordon Wood explains in Empire of Liberty that in “1801 the headquarters of the War Department, for example, consisted of only the secretary, an accountant, fourteen clerks, and two messengers. The secretary of state had a staff consisting of a chief clerk, six other clerks (one of whom ran the patent office), and a messenger. The attorney general did not yet even have a clerk.” Id. Throughout the 1790s, there was significant growth in the governmental offices, so the numbers cited for 1801 would have appeared to be a major jump from those in the first years after the adoption of the Constitution. Nonetheless, Jefferson and the Republicans were determined to reverse the trend of a growing federal government that began to resemble the bureaucratic monarchies of Europe. Jefferson’s perspective of the role of government, and the tension between the Federalists and Republicans on the desirable and proper size of the federal government continue to be relevant today. Obviously, the federal government has grown to include numerous other departments and agencies since the early Republic, but the same question is still discussed amongst common people, analysts, and politicians: how much of a presence should the federal government have in the common person’s life? While Jefferson and the early Republicans sought to limit the presence of the federal government to essentially handling the mail and foreign relations, the belief that the federal government needed to be involved in crucial aspects of Americans’ lives undoubtedly won the contest. Few Americans now would advocate abolishing Social Security, taxes, downsizing of federal agencies, and having a more passive, impotent federal government overall. These federal responsibilities feel necessary to the average American. Justifiably so, as the federal government is uniquely positioned to oversee the implementation of policies that benefit all Americans. Perhaps the gradual growth in the federal government, with occasionally growing under liberal-leaning presidents and Congresses and occasionally diminishing under conservative-leaning presidents and Congresses, was the best way for the United States to progress from a small republic to a global superpower. It seems that the healthy debate between the parties over the past two centuries of what the federal government should be is what kept the United States on a moderate path, never straying too far from its principles.
\|Caribbean Islands Table of Contents Barbados had an estimated population of 255,500 in 1987. Population density was 593 persons per square kilometer; slightly over one-third of the populace lived in urban areas. Annual population growth remained relatively low in the 1980s, averaging between 0.2 and 0.8 percent. In 1987 it was 0.6 percent. In spite of this success, Barbados remained the most densely populated country in the Eastern Caribbean. The primary reason for Barbados' small population growth was the government's ability to implement a nationwide family planning program that served to maintain a crude birth rate of 17 per 1,000 inhabitants for the 1980-86 period. In the past, emigration played a large role in stabilizing Barbados' population. From the end of World War II until the 1970s, Barbados exported its unemployed, as did the Windward Islands. Between 1946 and 1980, its rate of population growth was diminished by one-third because of emigration to Britain. The United States replaced Britain as the primary destination of emigrants in the 1960s because of Britain's restriction on West Indian immigration. In spite of continued emigration, Barbados began to experience a net inflow of workers in 1970, most coming from other Eastern Caribbean islands. By 1980 demographic figures began to stabilize because migration to Barbados had lessened, probably for economic reasons, and a relatively small natural population growth rate had been achieved. By the mid-1980s, expected real growth rates, adjusted for migration, remained below 1 percent. Ethnically, Barbados' population was dominated by descendants of African slaves. At emancipation in the late 1830s, the size of the slave population was approximately 83,000, three times that of the entire slave population in the Windward Islands. By the 1980s, distribution of ethnic groups was typical of the Eastern Caribbean; 90 percent of the population was black, 5 percent mulatto, and 5 percent white. Race largely defined social position in Barbados. The majority of whites still held a disproportionate amount of economic wealth in the 1980s and significantly influenced national politics through their control of business enterprises. Blacks constituted both the middle and the lower classes. In the 1980s, there was still a displaced social subgroup of extremely poor whites in Barbados who had not been fully assimilated into society. Descendants of the white labor class that had emigrated from Britain in the early colonial period, they had quickly been replaced as an economic group by African slaves, who had been brought to the New World as an inexpensive source of labor. Known as "Red Legs," the subgroup lived off the sea and subsistence agriculture and eventually became entrenched social outcasts, who had little expectation of becoming members of modern society (see The Sugar Revolutions and Slavery, ch. 1). Barbados inherited from the British a stratified society with a strong sense of class consciousness; Barbadian aspirations to reach the next rung of the social and economic ladder partially explain the industriousness of the population. Individual pride is clearly associated with economic status and has been cited as a reason for Barbados' early economic success, which surpassed that of the Windward Islands. Religion in Barbados was also influenced by the British. The first colonizers established the Anglican Church in Barbados, where it quickly assumed a position of dominance. Alternative religions were subsequently provided by Moravian and Methodist groups. Although Anglicans were still the dominant religious group in the early 1980s, they constituted only 31 percent of the population. The Church of God and the Roman Catholic and Methodist churches each claimed to minister to between 3 and 4 percent of the population. The remainder belonged to other religions or professed no religious affiliation. For more recent population estimates, see Facts about Barbados. Source: U.S. Library of Congress
Protectionists argue that protectionism is effective because it protects national economies and standards of living, and it protects infant companies from unfair global competition. On the other hand, protectionism inhibits free trade and slows down the growth of the global economy, argues BBC News.Continue Reading Governments implement protectionist measures and policies, such as subsidies, quotas and tariffs, and argue that they are effective in saving domestic enterprises and overcoming economic recession and unemployment. However, it is argued that protectionist measures are counterproductive because they can have a negative effect on a country’s economic growth, notes The Organization for Economic Cooperation and Development. Protectionists believe that restraining international trade allows infant companies to grow to a stage where they can compete fairly with large companies and gain from the economies of scale. They also argue that countries do not benefit equally from the comparative advantage of international trade because capital flows to where costs are lowest. Protectionism is also argued to be effective because it ensures that domestic products are at an advantage over foreign goods, states Wikipedia. Opponents of protectionism argue that it is narrow-minded and short-sighted. This is because it is not effective in addressing the problems of economic growth and unemployment, asserts BBC News. They also argue that free trade promotes exchange of capital and ideas, keeps prices low, and improves the standards of living, reveals CNN Money. Protectionism is also argued to be one of the causes of war. This is because of the protectionist policies among European countries that preceded the two World Wars.Learn more about Economics
An excellent way to avoid confounding is to assign individuals to the treatment and control groups at random, and then administer the treatment to those who were assigned to the treatment group. Randomization keeps the two groups similar apart from the treatment. If you are able to randomize individuals into the treatment and control groups, you are running a randomized controlled experiment, also known as a randomized controlled trial (RCT). Sometimes, people’s responses in an experiment are influenced by their knowing which group they are in. So you might want to run a blind experiment in which individuals do not know whether they are in the treatment group or the control group. To make this work, you will have to give the control group a placebo, which is something that looks exactly like the treatment but in fact has no effect. Randomized controlled experiments have long been a gold standard in the medical field, for example in establishing whether a new drug works. They are also becoming more commonly used in other fields such as economics. Example: Welfare subsidies in Mexico. In Mexican villages in the 1990’s, children in poor families were often not enrolled in school. One of the reasons was that the older children could go to work and thus help support the family. Santiago Levy , a minister in Mexican Ministry of Finance, set out to investigate whether welfare programs could be used to increase school enrollment and improve health conditions. He conducted an RCT on a set of villages, selecting some of them at random to receive a new welfare program called PROGRESA. The program gave money to poor families if their children went to school regularly and the family used preventive health care. More money was given if the children were in secondary school than in primary school, to compensate for the children’s lost wages, and more money was given for girls attending school than for boys. The remaining villages did not get this treatment, and formed the control group. Because of the randomization, there were no confounding factors and it was possible to establish that PROGRESA increased school enrollment. For boys, the enrollment increased from 73% in the control group to 77% in the PROGRESA group. For girls, the increase was even greater, from 67% in the control group to almost 75% in the PROGRESA group. Due to the success of this experiment, the Mexican government supported the program under the new name OPORTUNIDADES, as an investment in a healthy and well educated population. In some situations it might not be possible to carry out a randomized controlled experiment, even when the aim is to investigate causality. For example, suppose you want to study the effects of alcohol consumption during pregnancy, and you randomly assign some pregnant women to your “alcohol” group. You should not expect cooperation from them if you present them with a drink. In such situations you will almost invariably be conducting an observational study, not an experiment. Be alert for confounding factors.
Radioactive waste comes mainly from nuclear power production, but also from medicine, research, industry, and agriculture. Radioactive waste is produced in all EU countries and spent fuel in countries with nuclear power programmes and research reactors. While low and medium-level nuclear waste such as from medical equipment is increasingly being taken care of, there is not yet a single final repository for intermediate-level and high-level radioactive waste, such as spent fuel from nuclear power plants. Fourteen EU countries currently produce spent fuel which can take millions of years to decay. It is likely that the first repositories will be opened between 2020 and 2025 in several EU countries. Radioactive Waste and Spent Fuel Management Directive The EU's Radioactive Waste and Spent Fuel Management Directive requires that: - EU countries should have a national policy - EU countries draw up national programmes for the disposal of nuclear waste. These programmes have to include plans for the construction of nuclear waste disposal facilities - Relevant information on radioactive waste and spent fuel be made available to the public - EU countries invite international peer reviews at least every ten years - the export of radioactive waste to countries outside the EU is allowed only under strict conditions
Smooth landings A new control system lets a foam glider land on a perch like a parakeet. Everyone knows how an airplane lands: the slow maneuvering into an approach pattern, the long descent, the brakes slamming on as the plane touches down, bringing it to a rest about a mile later. Birds, however, can switch from barreling forward at full speed to touching down on a target as narrow as a phone wire. Why can’t an airplane be more like a bird? MIT researchers have now demonstrated a control system that lets a motorized foam glider land on a perch like a parakeet. The work could help improve the maneuverability of robotic planes, allowing them to recharge their batteries by alighting on power lines. Birds can land so precisely because they exploit a physical phenomenon called “stall.” A bird approaching its perch tilts its wings back at a much sharper angle than a landing airplane does. The airflow over the wings becomes turbulent, and the bird loses “lift,” the force that keeps it in the air. Fighter pilots practice stalling their planes in midair and recovering, but it’s too dangerous a maneuver for commercial aircraft, and the physics of stall have been much too complicated for autonomous vehicles to calculate in real time. Associate professor Russ Tedrake, a member of the Computer Science and Artificial Intelligence Laboratory, worked with Rick Cory, SM ‘08, PhD ‘10, to develop a mathematical model of a glider in stall. For a range of launch conditions, they used the model to calculate sequences of instructions intended to guide the glider to its perch. But, Cory says, “because the model is not perfect, if you play out that same solution, it completely misses.” So Cory and Tedrake also developed a set of error-correction algorithms that nudge the glider back onto its trajectory when location sensors determine that it has deviated from it. Using techniques developed at MIT’s Laboratory for Information and Decision Systems for studying nonlinear systems, they precisely calculated the degree of deviation the controls could compensate for. The addition of the error-correction controls makes for a trajectory that looks like a tube weaving through space. The center of the tube is the trajectory calculated using Cory and Tedrake’s model; the radius of the tube describes the tolerance of the error-correction controls. The control system ends up being, effectively, a bunch of tubes pressed together like a fistful of straws. If the glider goes so far off course that it leaves one tube, it will still find itself in another. Once the glider is launched, it just keeps checking its position and executing the command that corresponds to the tube in which it finds itself.
Adjustment in tuning (i.e. ‘tempering’) of mus. intervals away from ‘natural’ scale so that such pairs of notes as B♯ and C, or C♯ and D♭, are combined instead of being treated individually. This leaves neither note accurate but sufficiently so for the ear to accept it. In kbd. instr. this avoids unmanageable number of finger‐keys. The pf., organ, and other fixed‐pitch modern instr., are tuned to equal temperament, in which each semitone is made an equal interval, making it easy to play in any key and to modulate. Before equal temperament (which was introduced for pfs. in Eng. in 1846 and for organs a little later), the commonest system was mean‐tone temperament, which left certain keys tolerable, others less so, and some unusable. The untempered scale is known as just intonation. Instr. such as the vn. family can have no system of temperament, the player determining the pitch and checking it by ear. Some 20th‐cent. composers have restored 12‐note scale to just intonation. Others have used microtonal scales in just relationship. Still more have used ‘prepared’ instr. producing unexpected pitches, or elec. systems, or computers.
'Fresh Banana Leaves' spotlights Indigenous science for a warming planet As the world looks for ways to slow and adapt to climate change, solution-seekers need to turn to the insights and lived experiences of Indigenous people. Jessica Hernandez makes that argument in the new book “Fresh Banana Leaves: Healing Indigenous Landscapes Through Indigenous Science.” Hernandez, a University of Washington postdoctoral fellow from the Maya Ch’ortí and Zapotec nations, says Indigenous people are often viewed as research subjects, not experts in their own right. “Indigenous peoples hold on to the knowledge that can holistically protect our environments, especially as we continue to see how climate change impacts are drastically shifting our weather patterns,” she says. Hernandez titled her book after her father’s experience as a child soldier during the Central American civil wars. At 11 years old, her father was forced to fight. In his spare time, he sought refuge under a nearby banana tree, to which he fled one day during a bombardment. “He decided to do was to go under this banana tree that he had built a reciprocal relationship with … and he saw a bomb drop on the tree,” says Hernandez. “And the leaves kind of wrapped themselves to prevent the bomb from igniting. So my father says, ‘As long as we protect nature, nature will protect us.’ ” On how Indigenous sciences prioritize collaboration over competition. “One of the things about being an Indigenous scientist is that we understand the impacts colonialism had and continues to have on our people. And also… the climate change impacts. That it’s exacerbating our community disparities. And as Indigenous scientists, we work together to collaborate on ways that we can find solutions that will holistically heal our planet as well as our people.” On how urban environments are often Indigenous spaces. “We forget that … there are indigenous communities that are considered urban communities now because their environments have gone through these drastic changes. When we talk about Seattle, we can even talk about the history of how it was named after Chief Si’ahl, a Duwamish tribal leader, and how the Duwamish tribe is still fighting to kind of get federal recognition. “I think that because we tend to always connect Indigenous peoples to more rural places, we forget that urban cities are also built on indigenous lands. And that goes throughout the United States … Berkeley, San Francisco, Los Angeles and these major cities that hold political and economic power in our country.” On dealing with patronizing and condescending views toward Indigenous scientists “Fortunately for us, the narrative is starting to shift. But oftentimes [Indigenous scientists] are asked, ‘How is this science? Where is the data, the numerical data to support these claims?’ And I think that for Indigenous ways of knowing, not everything is translated into numerical datasets. Not everything is published in the peer review process. “And I think that oftentimes because in sciences we still continue to exclude lived experiences or personal narratives, it kind of continues to invalidate communities and ways of knowing that are centered on storytelling … lived experiences … traditions.” On the role of the patriarchy in climate science and Indigenous history “In the book, I talk about the Zapatista movement and how the Zapatista movement, which reclaimed land for many Maya communities in southern Mexico, continues to paint the man, [Subcomandante] Marcos, as the leader, when in reality it was the Indigenous women … who were leading the communities to reclaim their lands. And I think that oftentimes when we talk about environmental justice or climate justice, the men in our communities are continued to [be given] the front and center and the leadership of those movements when in reality is Indigenous women who are leading those efforts.” On what she wishes she had known when she entered scientific study “I wish I would have known that there was going to be a constant battle, especially when talking about Western sciences, when trying to bring in my entire self. Because I think that one of the premises of our Indigenous knowledge is that it centers our spirituality. But in the Western sciences, in the name of objectivity, we have to remove ourselves from the science that we practice.” On why more farmers should adopt the Indigenous practice of milpas “One of the Indigenous practices that I think people should use is our milpas, which are these holistic agricultural ecosystems that are very different from Western agriculture, that tends to focus more on just one crop … With the milpas, it embodies the three sisters, as we consider them in the southwest region of the United States: our corn, our beans and our squash. Because they’re relatives and they kind of take care of one another, they grow faster. It doesn’t require as much human labor as Western agricultural practices. “And through [the] milpas, we’re able to also have that intergenerational teaching where our elders are teaching our youth and everyone participates. It’s like a communal harvest where we are taught to take what we need and not necessarily what we want to take.” Book excerpt: “Fresh Banana Leaves” By Jessica Hernandez According to the National Science Foundation, in 2017, 71.1 percent of doctoral degrees in the sciences were awarded to whites in comparison to the 0.4 percent awarded to Indigenous students. 9 Thus the uncomfortableness of these conversations that acknowledge how settler colonialism is rooted in the sciences impacts mostly whites. However, it is important to realize that for Indigenous peoples, settler colonialism and its impacts continue to be our everyday experiences. While white scientists can choose to ignore these conversations, as Indigenous peoples we are reminded every day of how our culture, identity, lands, and other parts of our lives continue to be threatened and impacted. We see how white scientists continue to be oblivious to settler colonialism and how deeply rooted it is in the environmental sciences, physics, medicine, and other science fields. There is a failure to reflect on the founding history of these fields and how these founding histories continue to play a major role within the fields and disciplines that have been created from within. Settler colonialism grants certain scientists from wealthy countries such as the United States permission to go to other impoverished countries throughout Latin America and create their own research projects, centers, and other endeavors while further displacing the Indigenous peoples of those areas. Ecological and conservation research is often conducted by scientists from the United States, Canada, and other European countries that have the resources and autonomy to decide where they want to do research. In higher academia, we are taught that we can create a research grant proposal for “anywhere in the world.” I have come to learn that most of the time this statement refers to impoverished countries, and in the Americas that is Mexico and Central and South America (Latin America). This perpetuates the cycle of helicopter research where researchers from wealthy countries go to an impoverished country, conduct their research studies, and then return to their countries to analyze the data they collected and publish it, oftentimes not even including or consulting the local people of those countries. In Latin America, oftentimes this helicopter research leads to having white and Westerner researchers from countries that have a long history of colonization write our stories instead of supporting Indigenous peoples so that we can write our own stories. I remember my visits to Oaxaca when my grandmother was still alive. Oftentimes I would go to the local shops or outdoor markets to help her purchase fresh fish and other produce. We would sometimes see white men and women with fancy cameras and equipment coming down from their trucks. My grandmother would always roll her eyes and tell me to keep on walking and not to engage or talk to any of them. I did not understand why she despised them, because I thought they were journalists or newscasters, similar to what we had in the United States. Oftentimes many of the people in our pueblo ignored them and their Spanish interpreter as well. Under her breath my grandmother whispered to me, “M’ija, these are people similar to anthropologists. They are here to collect our stories and statements because they say they are conducting ‘research.’ However, they have offered so many people stipends for their stories and interviews but did not pay them anything. On top of that, they are working on a book to write our stories. What do you think about that?” At such a young age I replied to my grandmother, “Why don’t they help everyone in the pueblo instead to learn how to read and write so that our people could write their own stories instead?” Obviously, researchers who conduct helicopter research are not interested in what they can offer or what the community might benefit from, as their main goal is to collect data and then publish it to advance their careers. Helicopter research is the most common form of this top-down approach that the sciences continue to teach and amplify in academic institutions. Determining what kind of research is helpful without consulting the community or asking them what might benefit them is a top-down approach that can further harm the community, especially Indigenous peoples. In conservation, scientists are also taught that if something worked in one country, it might work in another one. This creates this mentality of one- size-fits-all. Utilizing the top-down approach promotes the creation of one-size-fits-all conservation solutions and practices that may not necessarily work for all Indigenous communities because Indigenous communities are not monolithic and their way of life is place based. Given that coastal communities are different from inland communities, the same conservation approaches will not work as they have to be adapted to meet the community’s needs. This is why it is best to center the community first, which derives from the opposite spectrum, following the bottom-up approach. I recall in my graduate school that a professor was very mad that his potential research project was cancelled because the local federally recognized tribes of the state of Washington were not interested in creating marine protected areas (MPAs) in the Puget Sound and Salish Sea. For him this was a great way to protect salmon because he had done other research projects in other developing countries to create MPAs for conservation purposes. MPAs are the conservation frameworks that have been applied to many impoverished and global south countries. He mentioned how he had “wasted” a lot of money trying to get this project started just for the tribes to say no to his proposal. This is an example of the combination of different top-down approaches I have discussed. He thought he knew what was best for the community as opposed to the communities, in this case tribes, knowing what was best for them. This is the settler colonialism that is embedded in conservation, where non-Indigenous scientists have not developed the same relationships with the local environment as tribes who have been cherishing these relationships for generations. He wanted to apply the one-size-fits-all model to tribes in the state of Washington because he had done similar projects on MPAs with other Indigenous communities in other countries. In conservation, we are taught that practices and approaches that were successful should be what we apply to different regions, places, and communities. This tends to ignore that every community holds a different set of values and relationships with their environments. Also the success of conservation practices and approaches is often determined by the scientists, not the local communities. Lastly, he had already decided his research project, because he was the scientist, instead of asking the tribes what kind of conservation projects they wanted to do in regard to their marine resources. We need to start discussing this top-down approach that is embedded in the sciences, in particular anything related to our environment, where scientists believe their academic credentials and experience can outweigh lived experiences and local knowledge. This is why reversing this topdown approach to become a bottom-up approach is crucial and essential to benefit local environments and communities. From “Fresh Banana Leaves” by Jessica Hernandez, published by North Atlantic Books, copyright © 2022 by Jessica Hernandez. Reprinted by permission of North Atlantic Books. This article was originally published on WBUR.org. Copyright 2022 NPR. To see more, visit https://www.npr.org.
Crop farming takes a lot of work and resources. Why do farmers leave wide strips of grass through their field? Shouldn't they plant crops everywhere they can? The farmer probably carefully planned those grass strips, called waterways. The grassed waterways are designed to do what their name says: Provide a planned path for way for water to flow. A permanent perennial crop, like grass, is put in place to hold soil and prevent erosion. Consider the heavy spring and fall rainfalls we see and the increase in severe weather in recent years. These occur at a time when the soil is most vulnerable. After a rainstorm, water can sweep through fields, taking topsoil with it. The swiftly moving water will start to create a small channels. With more rain, more water collects in those channels. Those small channels can become gullies and completely reshape farmland. Planning ahead for where water will flow with a grassed waterway has several benefits. Reduce erosion- The wide grassy area spreads water across a wider area as it leaves the field. This reduces the force of the water and makes it flow more slowly from the field, keeping fertile soil in the fields. Consider environmental impact- When topsoil runs off fields, so do the chemicals farmers use to keep crops healthy. Unfortunately those same chemicals that keep crops healthy can be devastate native flora and fauna. Grass acts as a natural filter and holds runoff back from streams. Future minded- Spring storms are becoming more frequent and severe. It's important to adapt to our changing atmosphere to keep food production sustainable. Grass waterways can lesson the burden of rain storms on farmland. How can Gravel Grading & Excavating help? Supporting farmers is the most important work we do. We'll move earth to bring the benefits of waterways to your farmland. Clearing and grubbing- We can clear plants that have overtaken waterways including tough roots and stumps. Grading- We can lay back the banks of the waterway to a better grade to keep soil in place and guide water slowly from the field. Planting- You can keep to planting the annual crops, leave the perennial ground cover to us. We can get your perennial ground cover started by laying grass mats. You'll find all the newest products and services recommended by Terry and Gravel Grading & Excavating.
Main Article Content Hypertension a silent killer is a major risk factor for cardiovascular disease worldwide and is one of the most important reasons to visit to physician. Hypertension leads to various complications as increased risk of stroke. Good control of blood pressure will result in prolonged survival. Increasing the knowledge, awareness, and control of hypertension will reduce morbidity and mortality. Studies show that many patients did not have appropriate knowledge about hypertension. Hypertension, referred to as high blood pressure, is a condition in which the arteries have persistently elevated blood pressure. The normal level for blood pressure is below 120/80, where 120 represent the systolic measurements and 80 represent the diastolic measurement. Blood pressure of 140/90 or above is considered hypertension. Though the exact causes of hypertension are usually unknown,there are several factors that have been highly associated with the condition. These include smoking, obesity or being overweight, being obese as a child, diabetes, lack of physical activity, aging, socioeconomic changes favoring sedentary habits, alcohol consumption, and high levels of salt intake. There is no guarantee that a person with hypertension will present any symptoms of the condition. About 33% of people actually do not know that they have high blood pressure, and this ignorance can last for years. For this reason, it is advisable to undergo periodic blood pressure screenings even when no symptoms are present. Hypertension speeds up brain aging!! As young and middle aged people with high blood pressure have a higher risk of accelerated brain aging, scientists from the University of California Davis reported in The lancet (November 2, 2012 issue). To achieve the good control of blood pressure, the programs like national public health programs and initiatives such as the National High Blood Pressure Education Programs as in U.S are required15. Considering the high morbidity and mortality due to hypertension, and knowing that if a patient has knowledge about the disease, patient will be more careful about the management, and a better control can be achieved.
Birds with orange bellies are in danger of being extinct. The majority of these species of birds live in the wild, and their numbers are still quite low. More than ever, a call for action is needed to prevent the extinction of these orange-bellied birds. We’ll list and describe seventeen distinct orange-bellied birds in this page and attempt to examine their genus, reproduction, and natural survival. Along the way, we’ll emphasize how important it is for humans to protect these birds from extinction. Allen’s Hummingbird – Selasphorus sasin Male Allen’s Hummingbirds have backs that are patinated bronze in hue, which become orange as they get closer to the rump. They have short, orange tails and tiny, gray wings. With the exception of a white v-shape at the apex of the breast, this bird’s belly and breast are orange and its rump is white on the underside. The male Allen’s Hummingbird has a broad, gray crown and an orange bib. His face is similarly orange. The black beak of this bird is long and straight. Size: These little birds have wingspans that are about 4.3 inches broad and measure around 3.5 inches from tip to tail. Beautiful small birds known as Allen’s Hummingbirds may be found on the West Coast and occasionally can be seen wintering in Mexico. Although the oldest known release was made at the age of 5 years and 11 months, these tiny fellas have a lifespan of 3 to 5 years. The Allen’s Hummingbird is a very high diver, which is an intriguing feature about it. Adult males of this species start out by soaring in a pendulum arc, sometimes rising as high as 65 feet, before temporarily rising higher and swooping down quickly on a female or a rival male! In the eastern part of North America, the Baltimore Orioles are a vibrant indication of spring. The mature males have black wings with white wing bands and brilliant orange and black coloring. The male birds have black heads and backs and orange chests and bellies. Females have a brownish-yellow back, grayish-brown wings, and a yellowish underside and head. They belong to the blackbird family and are around the size of a Robin but more slender. Breeding begins in April in the Eastern and Central States, as well as in the Central and Southern Provinces of Canada and along the Southern US Border. The Baltimore Orioles depart as early as July for their winter migration to Florida, Central America, and the Caribbean. They weave beautiful hanging nests that resemble bags out of fibers. Baltimore Orioles frequently visit parks and backyards when foraging for insects and fruit in open woods, along riverbanks, and along forest borders. They consume nuisance species by eating insects including beetles, crickets, and grasshoppers as well as spiders and snails. They can harm crops including raspberries, mulberries, cherries, bananas, and oranges since they devour a broad variety of fruits. Try placing oranges that have been chopped in half on a platform feeder or hanging from trees to draw more Baltimore Orioles to your yard. include sugar water-filled oriole feeders. Plant fruit and nectar-producing plants like trumpet vines, crab apples, and raspberries. Male Bullocks resemble Baltimores in appearance and share their brilliant orange breast and belly. Unlike the Baltimores, their heads only have black on the crown and nape. Their backs are completely black. An eye is struck by a black line. All females are yellow. During the mating season, Bullock’s Orioles may be found across the western part of the United States. These orioles’ and Baltimore’s respective ranges converge in the Great Plains. They frequently crossbreed here. They used to be referred to as the Northern Oriole because of this as well as their physical resemblance. We now know that they are not genetically connected in any way. The songbird Turdus migratorius, sometimes known as the American robin, is a member of the thrush family. Its species name, migratorius, denotes that this bird frequently migrates across the Eastern and Midwestern US, while its genus name, Turdus, is derived from the Latin word for “thrush.” The hue of the belly and breast of a male American robin, known as rufous or “reddish-orange,” makes it easy to identify. A female American robin is just slightly lighter than its male counterpart despite having a comparable hue. American robins often consume fruits and insects. The varying seasons and weather have a direct impact on their eating habits. For instance, American robins eat invertebrates in the summer and spring in addition to eating insects and earthworms. These birds eat fruit hanging from trees in the fall and winter. The state birds of Connecticut, Wisconsin, and Michigan are these species. A interesting fact: American robins are said to have 2900 feathers in total. American robins are frequently seen in suburban backyards and residences. It is well known that these birds can live in crowded areas and adapt. Female American robins seek refuge in wooded areas during the nesting season. Black-headed Grosbeak – Pheucticus melanocephalus Male Black-coloring headed’s and markings Grosbeaks have medium-length black and white wings with a white wingbar on each, and they have black backs. They have long, rounded tails that are white underside and black and white on top, with the exception of a black bar towards the rump. The bird’s head is black, with a white rump that has an orange mark on it. Its belly and breast are a gorgeous orange color that extends to the throat and over to the back of the head. These birds have gray bills that are conical, strong, and big. In contrast to their male counterparts, female and juvenile grosbeaks have a brighter orange colour with some streaking down the edges of the breast. Size: These Grosbeaks have wingspans that are around 1.6 inches broad and extend 7.1 to 7.5 inches from tip to tail. Diet: These birds eat grains, fruits, and occasionally even snails, whose shells they can easily break through with their strong beak. The Black-headed Grosbeak in more detail The Black-headed Grosbeak spends its winters in Mexico, but as the weather warms up, you may see these stunning birds all throughout the Eastern United States. They live just 5 to 6 years, however it turns out that the males make excellent fathers! They spend the same amount of time incubating the eggs that the females do, and after the chicks hatch, the happy pair devotes the same amount of time to feeding and caring for them. Additionally, unlike the majority of other birds, these birds possess a superpower. Monarch Butterflies come while they are spending the winter in Mexico, and the Black-headed Grosbeak starts to gorge itself. If you don’t realize that monarch butterflies are extremely poisonous, this doesn’t sound like such an amazing feat. The Grosbeaks successfully devour the Monarchs in intervals of 8 days thanks to their unique digestive systems. This allows the poisons to be safely consumed and eliminated before the subsequent feeding! Male Hooded Orioles have black necks and backs and range in color from brilliant yellow to bright orange from their crowns down to their bellies. The wings of females and immatures are more grayish yellow. Females lack dark facial marks as well. In Texas, male Hooded Orioles are typically orange in hue, whereas those further west are yellow. They build hanging nests on the undersides of palm fronds to reproduce in the southern US states. Some of them spend the entire year on the Gulf Coast of Mexico and Central America. They spend the winter in Mexico. Because of the easy access to food provided by nectar feeders, some Hooded Orioles have ceased migrating from southern US states. They prefer to reside next to palm palms in dry, open places. Around 20 feet above the ground, their nests are a hanging basket made of grass and plant material. To draw orioles, they will approach nectar feeders or utilize fruit. These lovely birds have blue heads and backs and a waistcoat that is orange that has been corroded. The females merely have a wash of orange on their chests and aren’t as vividly colored. These insectivores, as they are commonly known, will visit your feeders if mealworms are available and will quickly build their nests in birdhouses of the appropriate size. The western United States is home to a variety of year-round, breeding, migratory, and wintering populations of western bluebirds. Hirundo rustica, sometimes known as the barn swallow, is a type of bird intimately associated with agricultural advancements and human endeavors. These birds frequently breed in North America, Europe, and Asia. These birds breed throughout Central and South America in the winter. Originally preferring to build their nests in caves, these birds have started to breed and build their nests in farms where pigs and cows are maintained. Barn swallows frequently establish their nests on public structures. Barn swallows have been the subject of much investigation, particularly in European nations. North-Western Europe is a typical location for barn swallows. One of these studies examined the habits and food of barn swallows in Poland’s rural districts. This study has found that the decrease in these birds’ food sources is responsible for their population drop. A barn swallow seen in farm cattle mostly consumes huge Diptera and horse flies Tabanidae. These birds frequently exhibit a range of migratory behaviors. Their long-distance migration frequently takes place between mid-December and early January, or mid-june and early july. Barn swallows have adapted to live in these ecosystems while humans continue to construct infrastructure and farms. Eastern Bluebird – Sialia sialis Male Eastern Bluebirds are beautiful blue-backed birds with long blue wings and short blue tails. This bird has a pristine white belly and rump, with orange bordering at the belly that fills out the breast in density. This orange color extends over the back of the head and up to the throat, stopping only in a thin line at the bird’s chin. The rest of the bird’s face is blue, and its medium-length, slightly curved silver beak is silver. Females will have more muted orange at their breasts and a grayer, bluer hue. Size: The wingspans of these birds range from 9.8 to 12.6 inches in breadth, while their lengths range from 6.3 to 8.3 inches. Diet: Caterpillars, crickets, and beetles are the main foods that Eastern Bluebirds eat, although as the winter months approach, they will also scavenge for fruits and berries. Information about the Eastern Bluebird The Eastern Bluebird is a little bird with a long lifetime, often 6 to as high as 10 years. It lives year-round in the Eastern United States. These keen-eyed birds can spot microscopic bugs up to 60 feet away, so they don’t even require glasses! Additionally, it appears that Eastern Bluebirds are quite particular about their houses. Here is some advice if you are attempting to entice one to a nesting box but aren’t having any luck. An Eastern Bluebird will only settle in if the box’s base is a comfy 4-inches square and the entrance hole is 1 34 inches in diameter. If you truly want to hedge your chances, get or create a box with these measurements, and we believe that both you and those Bluebirds will be delighted with the outcomes! You could get fortunate with your existing box, but if you really want to hedge your bets, do that! Male Orchard Orioles have reddish-orange bellies and chests with black heads and backs. Females have darker wings and white wingbars, are generally greenish-yellow, whiter beneath, and darker on the back. Before heading south to Mexico and Central America in the summer, orchard orioles breed in the central and eastern states. Orchard Orioles prefer open woods, although they may also be found in backyards, open shrubland, riverbanks, farms, and backyards. They construct nests like hanging pouches. Insects including ants, caterpillars, beetles, grasshoppers, and spiders make up the majority of their food. Additionally, they will consume fruit like mulberries and chokeberries as well as floral nectar. Try nectar feeders or platform feeders with sliced oranges or mangoes to entice orchard orioles to your yard. Plant native berry plants as well, including chokeberries or mulberries. This phoebe has a dim orange cinnamon wash on its lower abdomen and an overall drab gray color. The orange wash stands out against the shades of grey even if it is not as vivid as other orange plumages on this list. These little flycatchers breed in Alaska, western United States, and a small portion of Canada. Their year-round range extends into Mexico and the southern states. Say’s Phoebes have lived in the United States for quite some time. Paleontologists have found this species’ fossils in Arizona, California, New Mexico, and Texas that date back to roughly 400,000 years ago (the late Pleistocene.) A shorebird known as the American woodcock, or Scolopax minor, has evolved to dwell in woods and woodlands. American woodcock populations have been steadily declining for millennia at a rate of one to two percent every year. American woodcock population declines are a result of illicit logging and deforestation. The US states of northern Illinois and Indiana are frequently home to these birds. American woodcocks require forest clearings for mating, daytime woodland thickets for sleeping, and foraging areas where they can find earthworms to eat. The “singing grounds” are the areas where male American woodcocks congregate in the early spring to locate possible female mates. For American woodcocks, a valuable habitat is provided by alder trees. These trees provide them with shade and defense from roving predators. American woodcocks respond favorably to well-managed environments, according to studies. when a terrain is abundant with farms, woods, and forests. The number of American woodcocks is likewise increasing. Color and markings: The magnificent Orange-breasted Sunbird has a turquoise upper back and shoulders and a faint orange and gray mixture on the rest of its back. They have very long gray tails and small wings that are primarily gray with some orange accents. This bird has a rich yellowish-orange rump, abdomen, and breast, with a purple breastband visible at the top of the breast. These birds have long, significantly curved black beak, and their heads are an iridescent dark green or turquoise. Size: The length of these birds ranges from 4.9 to 6.4 inches, and their wingspans are around 6.7 inches wide. Diet: Although nectar is this Sunbird’s main food source, it also includes tiny insects and spiders. Detailed information about the Orange-breasted Sunbird The Orange-breasted Sunbird, a stunning addition from South Africa, has an amazing lifetime of 16 to 22 years! Like the Baltimore Orioles, they have peculiar nesting practices. The female makes a ball-shaped nest, which she seals together in a ball-shape with cobwebs, by assembling leaves, parts of roots, twigs, and grass. Once the nest is prepared, it is hidden by a shrub where the mother will only deposit one or two white eggs with small brown flecks on them. Both the male and female Sunbirds take care of the young, although the male is a bit lethargic and delegated around two-thirds of the task to his girlfriend! They care for their young for around three weeks before leaving them to fend for themselves and starting the cycle all over again. The heads, chests, and bellies of Altamira Orioles have a vivid yellowish-orange color, while their backs, wings, and tails are all black. Black is also seen around the eyes and around the neck of these birds with orange heads. Juveniles have backs that are more olive than black and are more yellow in color. Except for the Rio Grande Valley in Texas, where they live all year round, altamira orioles are uncommon in the US. Look for them in southeastern Texas, along the Gulf Coast of Central America, at sunflower or nectar feeders, or in wildlife refuges. They favor open forests. All year long, Altamira Orioles remain in pairs. Try to locate their incredible, up to 2-foot-long hanging nests.
In this activity students will learn what conductors and insulators are. They will then carry out an experiment to determine what types of materials are conductors and which are insulators. Students will identify the properties that the conductive materials have in common and the properties that insulators share. - Outlines the difference between conductors and insulators - Provides students with an opportunity to determine what types of materials might be conductors or insulators - Students construct a simple electrical circuit - Students test the conductivity of a variety of materials - Students use their results to determine if materials are conductors or insulators - Students identify that conductive materials have common properties and insulating materials have common properties.
It is very common for young children or children with learning or developmental disabilities to have trouble organizing their thoughts in order to put them into well-written sentences or paragraphs. Students with writing difficulties may try to avoid writing assignments or get frustrated with writing. This can lead to a lack of progression in skills. Guided Writing can help. What is Guided Writing? Guided Writing is research-based writing strategy in which the adult guides the child through every step of the writing process, asking the student questions along the way, and providing the answers when necessary. The teacher or adult ensures the child is following capitalization, punctuation, and spelling rules, and that they are creating complete sentences with relevant details. This guidance provides the building blocks for becoming an efficient independent writer. When Should You Use Guided Writing? Guided writing can be applied to a variety of situations. It can be used to teach a child to write a simple sentence or a complex essay. It can be used to write about a weekend trip, a period in history, a fictional story, or really any topic of the writer’s choice. Meet your child at their current level, challenging them ever so slightly as you progress through the lessons with them. While Guided Writing is traditionally for students with at least some basic spelling skills, with speech to text and other technological programs available, it can be modified for students who are still learning to spell. It is Important to Encourage Your Writer Throughout the Process During a Guided Writing lesson, it is important to keep the writer motivated by acknowledging their small successes along the way. With enough success, they are likely to gain some internal motivation and start taking bigger risks. Praise your writer with comments such as “Nice work using a period” or “I like the details you included about…” Give specific positive feedback about what the child did, rather than more abstract praise like “Good job.” Specific positive feedback lets the child know exactly what is expected, which they can internalize and keep in mind for their next writing assignment. Incorporating choices and interest can also help keep your student motivated. Guided Writing is Implemented with Three Steps? Here I will illustrate a Guided Writing lesson example. I want you to try to think about how you might apply Guided Writing with your child or student(s) among a variety of possible writing activities. Step 1- Ask your child/student(s) to give you some piece of information, like what they did over the weekend. Encourage your child to provide specific details about the event. An answer with good details for writing would be something like, “I went to the beach with my cousin this weekend. We went swimming and I had a great time.” For some children, you may need to ask several questions to get the necessary details for the writing assignment such as: - where did you go over the weekend? - who did you go with? - what did you do there? - how did you feel when you were there? Other children will verbally provide these kinds of details without much guidance. Sometimes visuals (images online, drawings, or actual images of the child) can help a child describe or remember their experiences. For instance: How did you feel when you were at the beach? Happy 😃 Sad 😞 Tired 🥱 Step 2- After you get the details from your child/student, ask them to write down what they did over the weekend (providing as much assistance as needed). Ask them to say their first sentence out loud, using the details they just gave (e.g., I went to the beach with my cousin this weekend). Children learning to improve their written expression can verbalize their thoughts out loud before putting them on paper. Recording their thoughts on video or speech to text is helpful as well. They can refer back to the sentences they recorded to type or write them. If your child leaves out important details or words when verbalizing the first sentence or includes information from the second sentence (e.g., I went swimming and had fun), encourage them to say what happened first. You can ask questions like: - When did you go swimming with your cousin? - Where did you go swimming? When they say “this weekend” and “at the beach,” guide them through saying (or recording) the first sentence again if needed, “I went to the beach with my cousin this weekend.” Next, they can write it down, with support if needed. If other children are in the group you can ask if they would like to say their sentences aloud to each other so they can all hear what a first sentence may sound like. Provide as much guidance as needed for your child to get the whole sentence out. Have your child try to create a picture in their mind of the scene to really connect to what they are writing. Use real pictures (such as those from Google Images) if that will help your child formulate their sentence or keep their sentence in mind. Step 3 – When your child/student starts writing the first sentence down, you can ask them questions about capitalization and punctuation. Questions might include: - Should you start with a capital letter? - What should go at the end of your sentence? If your need help, tell/show them the rules (e.g., “The first letter of a sentence should be capitalized.”, “You end your sentence with a period.”). Provide a sample if needed. You can laminate general sentence cards so your child has a sample to refer to at each lesson. See sample sentence cards below: Sentence cards and multisensory games are a great way to build a child’s independence in the use of writing rules. How Should You Guide Your Child Through the Second Sentence? After your child/student completes the first sentence, complete the same steps if needed for the second sentence. Ask your child/student to think of what the next sentence would be. Have them say it out loud (and/or record it). Encourage your child to connect the second sentence to the first by adding more detail. For example: - First Sentence: “I went to the beach with my cousin this weekend.” - Second Sentence: “We went swimming and I had a great time!” If needed, ask questions to get the necessary details (just as shown above for the first sentence) and encourage your student/child to create a picture in their mind of what happened. In a group, children may want to share their second sentences with their peers as well to hear examples. Just like the first sentence, you may work on capitalization and punctuation by first asking the child/student to show or tell you what they should do, and then telling/showing them if they are unsure. You can remind them to refer to sentence samples, rules cards, etc. How Can You Help with Spelling During Guided Writing? Provide assistance with sounding out the words if your child is having trouble spelling. Refer to 12 Spelling Strategies Parents Can Try at Home if you are in need of more spelling support. Additional Information About Using Guided Writing with Children Keep in mind that the strategies in this article are recommendations. Please do not try to pressure a child into participating in any of these strategies. This can lead to frustration, which can turn your child off to writing practice. Remember to always stay calm when working with a child or student, even if you think they should be getting something that they are not getting. If you get frustrated with them, they may start to feel anxious, angry, inferior, stupid, etc. which will lead to a less productive learning session. Keep practice sessions short (2 to 10 minutes for younger children or children who get easily frustrated and 10 to 15 minutes for older children or children who can work for longer periods without frustration), unless the child is eager to keep going. Practice at regular intervals, and allow your child to do something they enjoy after practice. As stated above, incorporating choice and interest is shown to increase motivation. For more suggestions on ways to encourage children to complete tasks or assignments they do not want to do, read our articles How to Use Schedules to Improve Children’s Behavior and 3 Ways to Use Timers to Encourage Homework and Chore Completion. Ask for Additional Support for Your Student or Child When Needed Many children show improvement with Guided Writing strategies; however, some do not. If your child is significantly struggling with writing or acquiring other academic skills, despite consistent practice and guidance, talk to your child’s school and/or doctor(s). Clinicians and educators and can direct you to the appropriate professionals to determine what might be interfering with your child’s progress and what additional strategies might help. 1) Guiding Readers and Writers (Grades 3-6): Teaching, Comprehension, Genre, and Content Literacy, by Fountas and Pinnell. 2) Writing Assessment and Instruction for Students with Learning Disabilities, by Nancy Mather, Barbara J. Wendling and Rhia Roberts. Thank you for visiting Education and Behavior – Keeping Us on the Same Page with Research-Based Strategies for Children! Rachel Wise is a certified school psychologist and licensed behavior specialist with a Master’s Degree in Education. She is also the head author and CEO at educationandbehavior.com, a site for parents, caregivers, educators, counselors, and therapists to find effective, research-based strategies that work for children. Rachel has been working with individuals with academic and behavioral needs for over 20 years and has a passion for making a positive difference in the lives of children and the adults who support them. For Rachel’s top behavioral strategies all in one place, check out her book, Building Confidence and Improving Behavior in Children, a Guide for Parents and Teachers. If you want Rachel to write for your business, offer behavioral or academic consultation, or speak at your facility about research-based strategies that support children, email her at [email protected].
In the early days of the Industrial Revolution, no one would have thought that their burning of fossil fuels would have an almost immediate effect on the climate. But our new study, published today in Nature, reveals that warming in some regions actually began as early as the 1830s. That is much earlier than previously thought, so our discovery redefines our understanding of when human activity began to influence our climate. Determining when global warming began, and how quickly the planet has warmed since then, is essential for understanding how much we have altered the climate in different parts of the world. Our study helps to answer the question of whether our climate is already operating outside thresholds that are considered safe for human society and functional ecosystems. Our findings show that warming did not develop at the same time across the planet. The tropical oceans and the Arctic were the first regions to begin warming, in the 1830s. Europe, North America and Asia followed roughly two decades later. Surprisingly, the results show that the southern hemisphere began warming much later, with Australasia and South America starting to warm from the early 20th century. This continental-scale time lag is still evident today: while some parts of Antarctica have begun to warm, a clear warming signal over the entire continent is still not detectable. The warming in most regions reversed what would otherwise have been a cooling trend related to high volcanic activity during the preceding centuries. By pinpointing the date when human-induced climate change started, we can then begin to work out when the warming trend broke through the boundaries of the climate’s natural fluctuations, because it takes some decades for the global warming signal to “emerge” above the natural climate variability. According to our evidence, in all regions except for Antarctica, we are now well and truly operating in a greenhouse-influenced world. We know this because the only climate models that can reproduce the results seen in our records of past climate are those models that factor in the effect of the carbon dioxide released into the atmosphere by humans. These remarkable findings were pieced together from the most unusual of sources – not thermometers or satellites, but rather from natural climate archives. These include coral skeletons, ice cores, tree rings, cave deposits and ocean and lake sediment layers, all of which record the climate as they grow or accumulate. These archives provide long records that extend back 500 years – well before the Industrial Revolution – and provide a critical baseline for the planet’s past climate, one that is impossible to obtain otherwise. But why is there no clear warming fingerprint yet seen across Antarctica? The answer most likely lies in the vast Southern Ocean, which isolates the frozen continent from the warming happening elsewhere. The westerly winds that circulate through the Southern Ocean around Antarctica keep warm air masses from lower latitudes at bay. Ozone depletion and rising greenhouse gas concentrations during the 20th century have also caused this wind barrier to get stronger. The Southern Ocean currents that flow around Antarctica also tend to move warmer surface waters away from the continent, to be replaced with cold deeper water that hasn’t yet been affected by surface greenhouse warming. This process could potentially delay Antarctica’s warming by centuries. The delay in warming observed in the rest of the southern hemisphere is something we do not yet fully understand. It could simply be because fewer records are available from the southern hemisphere, meaning that we still don’t have a full picture of what is happening. Alternatively, like Antarctica, the southern hemisphere’s oceans could be holding back warming – partly through winds and currents, but perhaps also because of “thermal inertia”, whereby the ocean can absorb far more heat energy than the atmosphere or the land before its temperature markedly increases. Bear in mind that the southern half of the globe has much more ocean than the north. Essentially, then, the coolness of the southern hemisphere’s vast oceans could be “insulating” Australasia and South America from the impact of global warming. The question is, for how long? If our evidence of delayed warming in the southern hemisphere holds true, it could mean we are in in for more climate surprises as global warming begins to overcome the thermal inertia of our surrounding oceans. Could the recent record warming of Australian waters, and the subsequent damage to the Great Barrier Reef, be an early sign that this is already occurring? Recent research suggest that the mass bleaching event of the reef was made 175 times more likely by climate change. Following the recent severity of such extremes, a better understanding of how anthropogenic greenhouse warming is already impacting the southern hemisphere is critical. What to do about it Leading scientists from around the world met in Geneva last week to discuss the goal of limiting average global warming to 1.5℃ – the more ambitious of the two targets enshrined in the Paris climate agreement. Last year, global temperatures crossed the 1℃ threshold, and 2016 is on track to be 1.2-1.3℃ above our climate baseline. But here’s the kicker. That baseline is relative to 1850–1900, when most of our thermometer-based temperature records began. What our study shows is that for many parts of the world that estimate isn’t good enough, because global warming was already under way, so the real baseline would be lower. The small increases in greenhouse gases during the 19th century had a small effect on Earth’s temperatures, but with the longer perspective we get from our natural climate records we see that big changes occurred. These fractions of a degree of extra warming might seem insignificant at first, but as we nudge ever closer to the 1.5℃ guardrail (and potentially beyond), the past tells us that small changes matter. Helen McGregor will be online to answer your questions from 2pm AEST today. Post a query in the comments below.
After Emperor Claudius flexed the military might of the Roman Empire to conquer Britain, he planned to start collecting tributes from the British tribes, establish legions, and set up fortified sites throughout the country. Some tribes entered into agreements with the Romans, however, not all British tribes were willing to oblige. Let’s examine how different British tribes reacted to or rebelled against Roman rule. Cartimandua and the Brigantes Tribe The British tribes responded in various ways to Roman rule. Some of the tribes, particularly the ones in the south and east who had already had a lot of contact with the Roman province of Gaul, were actually quite happy to collaborate with the new Roman regime. In fact, in about A.D. 50, the queen of the Brigantes tribe, Cartimandua, actively helped the Romans to suppress the resistance of the Catuvellauni tribe by turning over their leader, Caractacus, to the Roman authorities. Incidentally, Cartimandua had a rather colorful career. In A.D. 69, she got tired of her first husband Venutios and divorced him in order to marry her armor-bearer, Vellocatus. This did not sit well with Venutios or with the rest of the Brigantes. Venutios put together an anti-Roman faction that overthrew Cartimandua, and she had to call in the Romans to restore her to the throne. There was a second rebellion after that, and this time, the Romans were not able to put Cartimandua back on the throne. All they could do was save her life. It took until A.D. 74 for the Brigantes to be subdued for good. Learn more about Celtic women, families and social structures. Queen Boudicca and the Iceni Tribe The rebellious factions within Brigantes were by no means alone in resenting Roman rule. One tribe, in particular, the Iceni of eastern England, broke out into a terrifying rebellion in A.D. 60, and this rebellion nearly swept the Romans out of Britain. The king of the Iceni, Prasutagus, had died without any sons, leaving only his widow, Queen Boudicca, and two daughters. The Roman authorities decided to incorporate the kingdom into the administration of the province. However, some of the local Roman officials overreached themselves when they were sent to carry out this annexation. Roman soldiers ended up flogging Queen Boudicca and raping her daughters. This is a transcript from the video series The Celtic World. Watch it now, Wondrium. This was a seriously bad move. Queen Boudicca rose in revolt and carried many of the other southern British tribes with her. According to the classical historian Cassius Dio, Boudicca rallied the Celtic tribes while wearing a torc, which was a characteristic Celtic symbol of authority. This sort of torc has been found in Britain, for example, at Snettisham in Norfolk, which was ruled by the Iceni. Some people like to speculate that this was actually Boudicca’s own torc, but that would probably be too good to be true. The Iceni and their allies seemed determined to erase all signs of the Romans in Britain. They killed the Romans and burned their settlements. They even managed to burn Londinium. To this day, if you dig down under London, you can find the layer of ash that is left from the huge fire that burned at the time of the revolt. They then proceeded north to Verulamium and beyond. They met the main Roman force in the Midlands, but they were decisively defeated. The Roman historian Tacitus tells us that Boudicca took poison to avoid capture, surely in order to escape the traditional fate of the enemies of Rome, where they’re paraded in a Roman triumph, like the Gaulish chieftain Vercingetorix a century before. Boudicca became very popular in the 19th century as an exemplar of the British fighting spirit. For some reason, Prince Albert, Queen Victoria’s husband, was a big fan of Boudicca. In 1902, a massive statue of Boudicca was erected on the Thames Embankment. So, residents of London, today can spend some time with the woman who burned the city to the ground and nearly drove the Romans from the island of Britain. Learn more about Celtic Britain and Roman Britain. The Caledonian Tribe The encounters with the Brigantes tribe and the Iceni tribe, among others, had spooked the Roman authorities. Over the next couple of decades, they decided to concentrate their efforts in Britain in the south and east, where they had had the most success thus far. The Romans mounted a major campaign into the north of Britain in A.D. 83, under the leadership of the Roman governor, a general named Agricola. Incidentally, the great Roman historian Tacitus was his son-in-law. The Romans had been trying for many years to bring the northern British tribe known as the Caledonians to battle. The Caledonians wisely declined to fight the Romans, because they knew the Romans had a far superior army. Instead, the Caledonians would appear and disappear, never quite providing a target that the Romans could strike at. Finally, the Romans brought the Caledonians to battle by marching north into Caledonian territory just as the harvest was being brought in, and the Romans went straight for the granaries. The Caledonians had to fight or starve. The Romans and Caledonians fought a major battle at a site known as Mons Graupius, somewhere in present-day Scotland, but the location of the battle has never been positively identified. It was apparently a complete rout. Tacitus tells us that 10,000 Caledonian soldiers were killed, while on the Roman side, only 360 auxiliary troops died. The Romans didn’t even have to deploy their main legionary forces. Rome seemed poised to bring all of the islands of Britain under its direct control. The Battle of Mons Graupius took place in late A.D. 83 or early A.D. 84. The Roman conquest of Britain was mostly completed by A.D. 87. The skirmishes with the northern tribes continued into the 2nd century, and a little over three decades later, in A.D. 122 Hadrian’s Wall was constructed to mark the boundary of the Roman Empire. The northern tribes continued to rebel and oppose Roman rule well into the 2nd century. Common Questions about British Tribal Rebellion to Roman Rule The Brigantes tribe was a British tribe that inhabited Britain before the Roman conquest of Britain. In A.D. 50, the queen of the Brigantes tribe, Cartimandua assisted the Romans to thwart the resistance of another British tribe named Catuvellauni tribe. Cartimandua was the queen of the Brigantes tribe between A.D. 43 and A.D. 69. She helped the Romans suppress the Catuvellauni tribe, another British tribe. She remained loyal to the Romans throughout her reign. In fact, in A.D. 69 the tribe overthrew Cartimandua, and she had to call in the Romans to restore her to the throne. There was a second rebellion as well when the Romans came to her rescue once again, but this time they were only able to save her life and failed to put her back on the throne. By A.D. 74, she had been subdued for good by the Brigantes tribe. Queen Boudica was the widow of Prasutagus, the king of the Iceni tribe. After the king’s death, the Romans decided to annex the kingdom, during which the Roman soldiers flogged Queen Boudicca and raped her daughters. Queen Boudica revolted against the Romans and formed an alliance with several southern tribes. They killed many Romans and burned their settlements, including Londinium, which was the precursor to present-day London. The Romans were able to conquer the British tribes in the southern part of Britain fairly quickly, but they faced stiff resistance from the northern tribes. The British tribe known as Caledonians, in the northern part of Britain, refused to fight the Romans for a number of years. Finally, in A.D. 83, the Romans forced the case by marching into Caledonian territory during harvest time and attacking the granaries. This forced the Caledonias into a battle, which took place at a site known as Mons Graupius. Hence, the name Battle of Mons Graupius. The Caledonians were decimated and over 10,000 of their soldiers were killed.
Lastly, the Social Constructivist perspective views emotions as the products of social learning and cultural conditioning. How a particular culture views emotions and the language it uses to talk about them will affect how members of the culture will learn to experience and express emotion. Although this theory does have evidence to support its main claims, it has not been rigorously tested in controlled field experiments. So are emotions independent of thinking? Are they mere unconscious reactions to external stimuli, or derivations of biological processes? Are their main purposes to help maintain homeostasis or ensure survival? Are they part of a communication process that creates, shapes and constructs our interpersonal relationships based on our perceptions of our own individual histories? (Richmond, Kia Jane) Most likely, they are some of each. Regardless, certainly, the easier it is for us to acknowledge, accept, integrate and release emotional stress, the less time our systems spend trying to process it. Discussion: In the discussion tab at the top of this page share your thoughts about emotions, what they are and how they affect how we function.
Assignment 1.2: A Changing World Final Paper Due Week 5 and worth 140 points ‘The discovery of America and that of the passage to the East Indies by the Cape of Good Hope, are the two (2) greatest events recorded in the history of [human] kind” – Adam Smith, in the Wealth of Nations,1776. Think about why he and many other notables supported this statement, especially the discovery of America. What was so important about this New World across the Atlantic Ocean from Europe? How did it change globalization in terms of trade, culture, societies, innovations, new and old world exchanges, and in other ways? You have already developed a thesis statement and developed an outline in which you identify three (3) main points relevant to your topic. Now you will develop the final paper in which you explore your main points in detail. Write a three to five (3-5) page paper in which you: - Introduce your paper with your previously crafted thesis statement. - Identify three (3) major aspects that demonstrate old and new world exchanges. Explain your responses with specific examples and details. - Identify three (3) specific groups that were affected by this global event and provide two (2) examples for each group describing how the group was affected. - Summarize how this discovery affected the life of the average working American during the colonial period. Use specific examples and details. - Use at least three (3) academic references besides or in addition to the textbook. Note: Wikipedia and other Websites do not qualify as academic resources. Your assignment must follow these formatting requirements: - Be typed, double spaced, using Times New Roman font (size 12), with one-inch margins on all sides; citations and references must follow APA style or school-specific format. Check with your professor for any additional instructions. - Include a cover page containing the title of the assignment, the student’s name, the professor’s name, the course title, and the date. The cover page and the reference page are not included in the required assignment page length. The specific course learning outcomes associated with this assignment are: - Recognize the main factors that led to America’s early development. - Use technology and information resources to research issues in American History to 1865. - Write clearly and concisely about American History to 1865 using proper writing mechanics. Click here to view the grading rubric.
the altitude of the Moon's orbit as it climbed up the gravity ridge from Earth to reach a halo orbit around L2, an Earth-Sun Lagrange point. Lagrange points are convenient locations in space where the combined gravitational attraction of one massive body (Earth) orbiting another massive body (Sun) is in balance with the centripetal force needed to move along with them. So much smaller masses, like spacecraft, will tend to stay there. One of 5 Lagrange points, L2 is about 1.5 million kilometers from Earth directly along the Earth-Sun line. JWST will arrive at L2 on January 23, 29 days after launch. While relaxing in Earth's surface gravity you can follow the James Webb Space Telescope's progress and complicated deployment online. NASA Web Site Statements, Warnings, and Disclaimers NASA Official: Jay Norris. Specific rights apply. A service of: LHEA at NASA / GSFC & Michigan Tech. U. Based on Astronomy Picture Of the Day
Influenza, commonly known as “the flu”, is an infectious disease caused by the influenza virus. Symptoms can be mild to severe. The most common symptoms include: a high fever, runny nose, sore throat, muscle pains, headache, coughing, and feeling tired. These symptoms typically begin two days after exposure to the virus and most last less than a week. The cough, however, may last for more than two weeks. In children there may be nausea and vomiting but these are not common in adults. Nausea and vomiting occur more commonly in the unrelated infection gastroenteritis, which is sometimes inaccurately referred to as “stomach flu” or “24-hour flu”. Complications of influenza may include viral pneumonia, secondary bacterial pneumonia, sinus infections, and worsening of previous health problems such as asthma or heart failure. Usually, the virus is spread through the air from coughs or sneezes.This is believed to occur mostly over relatively short distances. It can also be spread by touching surfaces contaminated by the virus and then touching the mouth or eyes. A person may be infectious to others both before and during the time they are sick. The infection may be confirmed by testing the throat, sputum, or nose for the virus. Influenza spreads around the world in a yearly outbreak, resulting in about three to five million cases of severe illness and about 250,000 to 500,000 deaths. In the Northern and Southern parts of the world outbreaks occur mainly in winter while in areas around the equator outbreaks may occur at any time of the year. Death occurs mostly in the young, the old and those with other health problems. Larger outbreaks known as pandemics are less frequent. In the 20th century three influenza pandemics occurred: Spanish influenza in 1918, Asian influenza in 1958, and Hong Kong influenza in 1968, each resulting in more than a million deaths. The World Health Organization declared an outbreak of a new type of influenza A/H1N1 to be a pandemic in June of 2009. Influenza may also affect other animals, including pigs, horses and birds. Frequent hand washing reduces the risk of infection because the virus is inactivated by soap. Wearing a surgical mask is also useful. Yearly vaccinations against influenza is recommended by the World Health Organization in those at high risk. The vaccine is usually effective against three or four types of influenza. It is usually well tolerated. A vaccine made for one year may be not be useful in the following year, since the virus evolves rapidly. Antiviral drugs such as the neuraminidase inhibitors oseltamivir among others have been used to treat influenza. Their benefits in those who are otherwise healthy do not appear to be greater than their risks. No benefit has been found in those with other health problems.
What do we mean by “El Niño?” The El Niño-Southern Oscillation (ENSO) is one of the most important and longest-studied climate phenomena on the planet. It can lead to large-scale changes in sea-level pressures, sea-surface temperatures, precipitation and winds–not only in the tropics but across many other regions of the world. ENSO describes the natural year-to-year variations in the ocean and atmosphere in the tropical Pacific. Sea-surface temperatures in the central and eastern equatorial Pacific cycle between above- and below-average. An El Niño state occurs when the central and eastern equatorial Pacific sea-surface temperatures are substantially warmer than usual (see Figure 1, top). La Niña conditions occur when the central and eastern equatorial Pacific waters are substantially cooler than usual (see Figure 1, bottom). A La Niña event usually, although not always, follows an El Niño event. El Niño refers to the ocean component of ENSO. Before 20th century scientists studied ENSO, Peruvian fisherman observed the warmer ocean waters off of the South American coast and the impact the temperature had on their fisheries. They named the phenomenon El Niño (the boy child) because the effects were often seen most prominently during the Christmas season. The Southern Oscillation part of the term ENSO refers to the atmospheric component: the shifting of atmospheric pressure between the central/eastern Pacific and the western Pacific. What are neutral conditions? Several years of neutral (or normal) conditions can persist between La Niña and El Niño events. In order to understand the ENSO cycle, we must first understand what the Pacific is like in its neutral state. The equatorial Pacific climate acts as a “coupled system” because the state of the ocean and atmosphere depend on each other. As the conditions of the ocean change, the atmosphere responds, and vice versa. The main indicators of these changes are pressure and temperature. See Figure 2 (top) for a graphic illustrating neutral conditions. During neutral years (and on average) atmospheric pressure is low in the warmer western tropical Pacific (referenced at Darwin, Australia), and relatively higher in the cooler central/eastern tropical Pacific (referenced at Tahiti). Air naturally moves from areas of high pressure to low pressure, so this difference in pressure moves the equatorial air, known as the trade winds, from the coast of South America toward the western Pacific Ocean. The sun heats water at the surface of the ocean, but the trade winds push surface water by friction from east to west in the Pacific. Cold water from below moves up to replace the shifted surface water in a process referred to as upwelling. During neutral conditions, waters in the eastern Pacific are upwelled along the equator and the coast of South America. Because the upwelled equatorial and coastal waters originate deep below the surface, they are cold and rich with nutrients. When the surface water arrives in the western Pacific, land surfaces restrict its further movement and so the water “piles up”, making sea level approximately half a meter higher around Indonesia than it is off the coast of Ecuador. As the water accumulates and stagnates, it continues to warm. The Coupled System Because low-level winds move toward warm surface waters in the tropics, the difference in sea-surface temperatures (SSTs) between the cooler eastern Pacific and warmer western Pacific reinforces the easterly trade winds during neutral conditions. This east-west SST gradient induces strong easterly winds, which force water to the west and cause greater upwelling of colder water in the east. The cold upwelled waters also increase the east-west SST gradient, again reinforcing the strong easterly trade winds across the Pacific. The ocean and the atmosphere thus create a coupled system that continues this process until it is disrupted. What changes during El Niño years? Perturbations to the ocean that cause changes in the main temperature patterns affect the winds in this coupled system, which can lead to a positive feedback loop. During El Niño, this loop often begins with weakened, or sometimes even reversed, trade winds. The source of the weakened winds is not always apparent, but depending on their strength and how long they last, they may trigger Kelvin waves. These waves are 100-200 meters below the sea surface and hundreds of kilometers wide, and they make water warmer as they travel eastward across the equatorial Pacific (learn more about Kelvin waves here). Sometimes, these warmer waters make their way to the surface, and a “tongue” of warm surface water forms – typically warmer by 1-3 degrees Celsius and stretching across the equatorial Pacific. The warmer waters lower air pressure across the central and eastern Pacific, weakening the pressure gradient that would normally force the trade winds from Tahiti toward Darwin. The weaker trade winds reduce the amount of surface water pushed to the west, and the surface water stays warm and reinforces the weakened pressure gradient. This feedback can sustain El Niño conditions for more than a year. See Figure 2 (middle) for a graphic illustrating El Niño conditions. The direct effects of the changes in temperature and pressure often include increased rainfall along the western coast of the Americas, and decreased rainfall around Indonesia and Australia. What is La Niña? La Niña occurs as an enhanced version of the neutral state. When air pressure is higher-than-average in Tahiti and lower-than-average in Australia, the easterly trade winds blow more intensely than usual. The colder-than-normal ocean water extends across the eastern and central equatorial Pacific, and the winds continue to push water westward, once again increasing the sea level around Indonesia. The water in the western Pacific warms up, which then increases precipitation in the region. See Figure 2 (bottom) for a graphic illustrating La Niña conditions. How do we measure ENSO? Because of the social implications for announcing a developing El Niño, measurements must be verified and accurate. One ENSO indicator is the Southern Oscillation Index (SOI), which is calculated using the pressure differential between Tahiti and Darwin. The SOI is negative during El Niño years and positive during La Niña years. Because the SOI measurements can reflect local variability and weather disturbances, scientists usually average the readings over a 5-month period to determine whether the pressure fluctuations indicate a major event. Additionally, the U.S. National Oceanographic and Atmospheric Administration (NOAA) maintains monitoring buoys called the Tropical Atmosphere Ocean (TAO) Array across the equatorial Pacific Ocean. The buoys record and transmit sea surface and sub-surface temperatures, atmospheric conditions, water currents and wind data to scientists and researchers around the world in real time. The region monitored by the TAO array is split into different sections (see Figure 3), each of which has a different implication for the likelihood of ENSO. For instance, the NINO1+2 area may be the first to warm during an El Niño, the NINO3 region experiences the most temperature variability, and NINO4 readings are a strong indicator for precipitation conditions over Indonesia. It is the readings over NINO3.4 – capturing both the important SST variability and the changes of strong precipitation – that inform most predictions about how ENSO events may affect global climate variability and shifting rainfall patterns. How do we know when El Niño or La Niña is happening? Scientists who monitor the atmospheric and oceanic data in the Pacific track how temperature and pressure measurements deviate from the average and how long this persists. The designation of how far above or below normal the sea surface temperatures and/or atmospheric pressure must be – and how long they must persist – to qualify an El Niño or La Niña event varies slightly among different forecast centers and countries. While there is no single agreed-upon ENSO indicator, NOAA defines an El Niño (or La Niña) event when the NINO3.4 area has sea-surface temperatures at least 0.5º Celsius warmer (or cooler) than normal for five consecutive three-month-averaged periods. Why does ENSO matter? Learn more about the effects of El Niño and La Niña on global weather, climate and society. Delve into the science What to know more? Here are some recent publications from IRI scientists studying ENSO models and forecasts: Barnston, A. G., Tippett, M. K., 2013: Predictions of Nino3.4 SST in CFSv1 and CFSv2: a diagnostic comparison. Climate Dynamics, 41, 1615-1633. DOI: 10.1007/s00382-013-1845-2 Barnston, A. G., Tippett, M. K., L’Heureux, M.L.; et al., 2012: Skill of real-time seasonal ENSO model predictions during 2002-2011: Is Our Capability Increasing? Bulletin of the American Meteorological Society, 93, 631-651. DOI: 10.1175/BAMS-D-11-00111.1 http://journals.ametsoc.org/doi/abs/10.1175/BAMS-D-11-00111.1 Barnston, A. G., Tippett, M. K., Shuhua, L., 2012: Performance of Recent Multimodel ENSO Forecasts. J. Appl. Meteor. Climatol., 51, 637-654. DOI: 10.1175/JAMC-D-11-093.1 Barnston, A. G., Shuhua, L., Mason, S.J., et al., 2010: Verification of the First 11 Years of IRI’s Seasonal Climate Forecasts. J. Appl. Meteor. Climatol., 49, 493-520. DOI: 10.1175/2009JAMC2325.1
We the People The U.S. Constitution Starting with the failed Articles of Confederation this unit looks at how the Constitution ultimately arose out of great compromise and guided the direction the direction of this country. We will look closely at the Articles as well and the powers assigned to states and local governments. We will close with an in-depth look at our rights as defined in the Bill of the Rights. Essential Question: Should the Constitution have been ratified as originally written without the promise of a Bill of Rights? Constitution PowerPoint Lecture Notes (Music and videos have been removed for copyright reasons, thanks Congress!) Well, it's up to the delegates. Trace the origins of the Constitution. Those words are so small, what's actually in the Constitution? An admittedly boring presentation thanks to Congress making laws that don't allow me to include the videos. WHERE IS THAT IN THE CONSTITUTION?! Labs and Activities 1. How Governments Work - In this lab students make a series of decisions using different government models. Experience tyranny in all its forms- from the maniacal monarch to the mob majority! Introduces key pre-founding documents like the Mayflower Compact and English Bill of Rights. Download the file and read the instructions in the page notes at the bottom of each slide. 2. The Preamble - A comparison of the first draft of the Preamble to the one that was agreed upon. Afterwards students turn the Preamble into a storyboard to help them understand each line. 3. State Perspectives on the Constitution - Brief information sheets along with Close Reading analysis for each state (minus Rhode Island) to help prepare students for the Constitutional Convention Simulation. 4. Constitutional Convention Simulation - [Script I Student Worksheet] A simulation of the compromises that came about to make the Constitution possible. Students take on the role of a specific delegate, debate issues and participate in parliamentary procedures. Day 1 covers the Great Compromise. Day 2 includes the 3/5s Compromise and the question of the presidency. The Role Cards come from TCI's History Alive. The simulation can be done without them using just the State Perspectives sheets above. Here are some cards I made myself to give you an idea of what they include. 5. You Be the Judge - A stations-based lab where students in small groups consider whether a set of scenarios contain any violations of the Bill of Rights. 6. 3 Branches Graphic Organizer and Poster - Students in groups will research one branch and create a poster/museum display to share that branch with the rest of the class. This will serve as the instructional step for the Super Hero lab soon to come. 7. Super Hero Branches - a lab where students imagine each branch as a super hero giving them powers, sidekicks and weaknesses. They then "battle" their heroes against each other in the ultimate test of checks and balances. 8, HAT - States vs. Feds - A Close-reading of an article from The Atlantic magazine exploring the increasingly small separation between state and federal government in the US. 9. Stations: The Anti-Federalists - Adapted from a "historical scene investigation" lab this activity has students examining arguments against the ratification of the Constitution. 10. Constitution DBQ - Students analyze documents from their textbook and online sources to answer the question: Should the Constitution have been ratified? 11. Constitutional Crisis Breakout - A series of puzzles for students to solve in order to unlock the ultimate weapon against tyranny. (Put copies of the pocket Constitution in the final treasure box!) 12. Political Agenda Card/Role-playing Game - Based on an activity from iCivics.org students take on various roles representing the three branches. Each player has their own personal agenda they are trying to complete to earn bonus points. It's a complicated mess - just like government!
know your strengths and challenges Every person has their own set of talents, skills and character strengths. You will have used many of yours so far in your schooling and life in general. Knowing what they are and how you use them may help you cope better with the transition to tertiary study. You may feel more positive if you find ways of using them at university or TAFE. Talents are qualities that you are born with and may be improved by purposeful actions. Examples of talents are perfect pitch in your singing voice, good memory or an ability to draw images. Skills are a learnt ability that you have developed over time in order to carry out certain activities. Examples of skills are writing assignments, carrying out science experiments or managing your time. Character strengths are virtues that you develop and use by choice. Examples of character strengths are kindness, fairness, curiosity and honesty. Knowing your character strengths and finding ways to use them every day is a good way to build mental well-being and cope with new situations such as making the transition to tertiary education. Some characteristics of people with ASD can mean they have talents and skills that are beneficial for tertiary study. Example 1: Many people with ASD have a strong focus on a particular subject or area of interest. If this interest is part of your tertiary studies, it will mean that you will have knowledge and information, and are highly motivated to learn more about this topic. It may also mean that you are less likely to become easily distracted from your studies. Example 2: Many people with ASD have a very good ability to absorb facts and remember them. This will make learning new factual information easier for you. Example 3: Being honest and reliable may mean that you can take on some additional roles, such as helping with equipment or filing notes. These roles can help you to gain valuable skills. In Exercise 2 (linked below) you can use it to write down some the skills you have learnt and developed. Try to focus on those that will help you with your studies. Ask your family members and current teachers what they think your skills, talents and character strengths are. In Exercise 3 (linked below) ask your family members and current teachers what they think your talents and character strengths are. All people have things that they find harder to do. These can cause challenges for your studies. In Exercise 4 (linked below) you can use it write down some of these things. Focus on those that you think will affect your studies. Try to write down some solutions or strategies that could be used to help with these difficulties. Particularly think of how you can use your strengths and skills to make things easier. These strategies will be discussed later in this booklet, so you can come back to this later if you have more ideas. question & answer question: How can knowing my skills and strengths assist me to cope with the transition to tertiary study? answer: Knowing what your skills and strengths are can assist you in transition and other stressful times in a number of ways. Reminding yourself of your skills and strengths can improve your confidence, which helps you with new situations. Also knowing when you previously used your skills and strengths may help you find ways to use them in the new learning environment. question: I have a lot of knowledge and skills in my specific area of interest. Am I able to focus on this in all my study? answer: No, you most likely will not be able to solely focus on your particular area of interest in your studies. You will need to learn about other viewpoints, theories, or applications in this area. Use your depth of knowledge and your interest in the subject matter to motivate you to learn more, and to compare and contrast other viewpoints. who can help?
Sleep essential for child brain development Parents have one more reason to make sure their little ones get a good night’s sleep. A new study says consistent sleep is essential for brain development in young children. Researchers at the University of Colorado Boulder measured the brain activity of children numerous times at ages, 2, 3 and 5 years old. Using electroencephalograms (EEG), study leaders discovered that the neuro-connections between the right and left sides of the brain grew significantly stronger as the children slept. When those connections are strengthened, overall brain function increases and matures, study leaders said. On the contrary, when sleep is lacking, brain development may be hampered. The findings were published in the journal Brain Sciences. “I believe inadequate sleep in childhood may affect the maturation of the brain related to the emergence of developmental or mood disorders,” said research leader Salome Kurth in a news release. Though scientists aren’t exactly certain how sleep actually strengthens the brain, they know those healthy connections are important for language development and attention span. The new discovery is just one of a number of sleep studies that prove the importance of shut-eye for children, especially teens. Recent research from the University of Pennsylvania found that if teens get more sleep, they may decrease their risk for being overweight. The findings showed that for each hour more a child slept on a regular basis, their body mass index (BMI) levels fell into a healthier range. Fewer hours of sleep were associated with higher increases in BMI for the teens, ages 14 to 18. Additionally, sufficient sleep among teen athletes could also keep them safer on the playing field, says a study presented to the American Academy of Pediatrics recently. Researchers found that adolescent athletes who sleep at least eight hours nightly were a whopping 68 percent less likely to sustain an injury than their counterparts who get less sleep. About the Author health enews staff is a group of experienced writers from our Advocate Aurora Health sites, which also includes freelance or intern writers.
You may not realize how much of the night sky you can see with just your naked eye. The Andromeda Galaxy, Orion Nebula, Double Cluster, and more are all naked eye objects. You can even see the Milky Way at a dark sky site spanning across the entire sky! January 26, 2023 The rare, green Comet C/2022 E3 (ZTF) is making its first trip through our solar system in 50,000 years. So, how can you view this glowing beauty before it’s too late? December 07, 2022 When it comes to astronomy, every year is a little different and every year brings its highlights. This year starts with the Quadrantid meteor shower and every planet, except Mercury, is visible in the evening sky. Learn more about what we'll see in the sky in 2023! November 02, 2022 The Moon doesn’t have any light of its own, but (like the Earth) it reflects the light of the Sun. It takes the Moon about 27 days to complete an orbit of the Earth, and as it moves, sunlight strikes its surface. Half of the Moon’s surface is illuminated by sunlight while the other half remains in darkness. The phase of the Moon is determined by how much of the sunlit side we can see from the Earth. June 23, 2022 Look up at the sky on any clear, dark night and you’ll find yourself staring at hundreds of stars. It’s impossible to tell, but these stars are actually slowly moving through space. Of course, you’d have to wait a long time to notice any change, but very occasionally you might see what looks like a star go streaking across the sky. Obviously, the stars don’t move that quickly or fall from the sky, so what exactly is a shooting star? What’s a fireball? And why do meteor showers occur? June 14, 2022 The Moon isn’t always the consistent companion we expect -- at times it’s clearly seen in the evening sky, while on other occasions it appears ghostly gray against the pale blue of the morning or afternoon. Careful observation reveals a pattern to its appearance, known as the phases - but why does this happen? June 09, 2022 If there’s one thing that draws almost every observer, with or without a telescope, it’s the Moon. It’s understandable; it’s frequently easily seen in the evening sky and, with its changing phases, it’s been an object of fascination for millennia. Nowadays, with the inexpensive and easy availability of telescopes, more and more people are turning their attention toward it. But what, exactly, can you see on the Moon? May 24, 2022 It’s been said that astronomy is the oldest science. Before our ancestors even invented language and learned how to write, they were staring up at the heavens. The stars themselves were unimaginable mysteries; tiny points of light that seemed to burn like unmoving embers from a far distant fire. And yet, five were still. Five appeared to move. April 06, 2022 You’ve probably heard of a nebula before. Maybe it’s because you’ve seen them in sci-fi movies and TV shows, where they’ll hang in the background to make the blackness of space look more appealing. They’re often stunningly beautiful in photographs and can sometimes hit the headlines, usually thanks to discoveries by the Hubble Space Telescope. June 13, 2018 Turn off your lights and head outside on a clear, dark night. Leave your cell phone behind. If you have a planisphere, bring it with you. A planisphere, or star wheel, is a simple way to locate which constellations are up and where they are placed in the night sky for a particular date and time.
The voltmeter is a device, which is used to measure the difference between the electrical potential between two points in an electric circuit. It has a pointer which moves across a scale on the basis of the voltage of the circuit. It offers a numerical display of voltage by using analog to digital converter. It is represented by the letter V in a circle. In the market, the device is available in different range of styles. It is usually mounted in a panel and is used to inspect generators and other fixed apparatus. The device is completely accurate and ranges from a fraction of a volt to several thousand volts. It is one of the safest ways to measure the voltage. The device is also used to check if the battery is charged or drained. In case a car is not getting started, one needs to check if the battery is working properly. In everyday devices, the voltage can be checked using a voltmeter. In today’s time, the devices are designed using state-of-the-art technologies, the voltmeter is used to measure different magnitudes. The transmission lines usually carry high voltage and a special type of voltmeter is used to measure such dangerously high voltage. Such voltmeters have extra electrical insulation between the test point and the user. The other voltmeters are used to measure a very low level of voltage on small devices like computer chips. The product can be purchased easily from electrical stores or one can purchase from online portals also at a discounted price, with the added facility of delivery at the doorsteps. The attributes of a top-notch voltmeter are as follows- • Rigid structure • Seamless finish • Efficient functioning • Superior Performance • Trouble-free usage • Easy maintenance • Long working life • Long working life The suppliers of the voltmeter in India should adopt the following business practices in order to gain a competitive edge in the market- • They should procure the devices from the reputed vendors in the market, who make use of the top-notch grade components and technologically advanced machines for the production. • They should be backed by a team of dexterous professionals, which is highly proficient in handling and processing the orders in a prompt manner • These suppliers should thoroughly adhere to the standards and norms laid down by the industry. • They should have enough capacity to suffice the bulk and urgent requirements of their clients on a timely basis. • The suppliers of the voltmeter should be well-equipped with a widespread marketing and distribution network. This enables them to meet the requirements of geographically distributed clients. • They should offer them at a cost-effective rate, to penetrate a large client base. Thus, we can conclude that the wide applicability of these devices has led to an ever-increasing demand for them in various parts of the world.
Human beings are born with the need and the desire to communicate. Of course, we don't begin speaking in words or sentences until about two years old, but we start communicating immediately. Every parent can tell you the difference between a hungry cry, an angry cry or a cry of exertion. These are your child's first attempts at communication. Cries, along with smiling, looking into your eyes, watching your mouth move while you speak are all part of infant communication. As early as 18 months, we learn up to eight new words every day and, by three years old, we can use this newfound vocabulary correctly in full sentences. Studies show that these first three years of life will lay the groundwork for a lifetime of communication, so parents and caregivers can make a profound difference. There are many ways we can support their developing language skills and our role begins during the first few days of life. Actively listen when your child attempts to communicate. For an infant, communication can be cooing or smiling. Encourage these efforts by responding in kind, mimicking the sounds they're making, smiling, and making eye contact. By three or four months old, your child will begin to babble and imitate the sounds of their mother tongue. WATCH: How baby talk is vital to language development. Story continues below. When you're focusing on them, you can often tell what they're referring to, and give them the word they might be trying to say. Then pause. This pause is key because it gives the child time to understand and respond so the back and forth can continue. When you show interest, it encourages the child to redouble their effort because they are confident that what they are saying is being heard, understood and valued. At the same time, their brain's neural pathways are being primed and greased by these encounters. The more they attempt to communicate, the faster the brain will send messages and, through repetition, they begin to understand more quickly and completely. This babbling is truly the beginning of a lifelong conversation. Long before your child begins to speak, they can understand most of what you are saying. In fact, well before they produce any words, they are constantly adding new vocabulary to their lexicon and, at the same time, internalizing grammar and sentence structure. So, don't underestimate them. You can use large words and speak in full, complex sentences because young children are sponges for descriptive language and will soak up as much as you offer. Be sure to speak clearly and slowly so they have time to understand each word. Young children learn best through real experiences that interest them, so try to attach conversation to movement and a sensory experience. They will remember what "squishy" means if they are simultaneously squishing mud between their toes. Tasting a lemon and hearing the word "sour" will resonate, too. If you're at a loss of what to say to someone who can't talk back yet, try linking the words to something you are currently doing. You can name what's in the room, the parts of their body, or what you see, smell and hear during a walk through the park. Narrate tasks such as unloading the dishwasher or changing their diaper. You'll find daily life is full of rich vocabulary if you just start talking. As your child gets older, you will become a translator of sorts. One of the most frustrating things about being a toddler is that they understand far more than they can express. They know what they want, and they may even have some of the vocabulary, but somehow the idea just isn't coming out coherently. This is where you can help by giving them words to explain themselves. Think of your child at the very beginning of their life. Undoubtedly, they watched you while you spoke, studying your mouth and lips as you produced the different sounds of their mother tongue. By three to four months old, they were imitating those sounds and practicing new syllables and tones. This is how the child builds the muscles in their lips, tongue, palate, and larynx to produce language and make the sounds unique to their mother tongue. How can you help? Encourage babbling, blowing bubbles, and sounds of all kinds. Repeat what they say and follow up with questions or affirmations. Later, you can ask open-ended questions to keep the conversation going. The more time the child spends exercising these muscles, the more clearly they will be able to enunciate and express themselves. Read. Every day. Read with your child and model reading books yourself. When your child sees you reading books, they internalize the value of reading and will come to view it as a pleasure. When you're reading with your child, let the words jump off the page. Use gestures to demonstrate action words so the meaning is more clearly conveyed. Look at picture books and have a conversation about what you see. Rather than just reading the book as written, ask your older toddler "what do you think will happen next?" before turning the page enticingly. Finally, it's crucial to trust that your child's language will come. It's easy to become obsessed with developmental milestones and comparing your child with others. But learning happens when children feel safe, secure, and loved so it's best to keep language play light and fun. Sing songs, recite poems and use fingerplays to entice them with the rhyme and rhythm of language. Avoid testing. It may seem innocent, but constantly hearing "what's this?" or "what colour is that?" can be stressful for someone who isn't quite sure of the answer or has become bored with the questions. It's not necessary to correct pronunciation in young children as their speech will naturally evolve until all those adorable toddler phrases fade away and your six year old is left speaking fluently. Instead of correcting them, just repeat the word in your own sentence so that they hear the way it should sound. Of course, if you are concerned that there may be a hearing delay or problem with the development of your child's mouth, start a dialogue with your child's doctor early. That way, if there is a problem, you can see a specialist sooner rather than later. More from HuffPost Canada:
Iberia was also relatively warm during the last Ice Age, between 18,000 and 24,000 years ago, presenting a more welcoming climate for animals and people who retreated from the rest of Europe. …The researchers also discovered that between 8000 BC and 5500 BC, Iberia’s hunter-gatherers were genetically different from each other. This suggests that they interacted with a different group of hunter-gatherers during the Mesolithic era before Anatolian farmers, or those from what is presently Turkey, moved to Iberia and transformed the area yet again. The farmers also mixed with hunter-gatherers, according to their DNA …Beginning in 2500 BC, the researchers discovered, Iberians were joined by people from central Europe whose showed genetic ancestry from the Russian steppe. And over a few hundred years, the locals and the central Europeans interbred. Before this, there is no evidence that locals came into contact with anyone from outside the area. But that changed after 2000 BC, when 40% of Iberian ancestry and 100% of the fathers in the study could be traced back to central Europe. …The research also sheds light on why the language and culture of present-day Basques are so distinct from those of Iberians. The modern people of Basque Country, in northern Spain, are genetically similar to the Iberian Iron Age people with ancestry from the Russian steppe. While people around them mixed with different groups and changed, the Basques held on to their heritage. …Genetic data will need a boost from what anthropology and archaeology can show about the underlying causes for why this Y chromosome shift happened, the researchers said.
What is encryption and what do we need to encrypt? That is an important question that I hope to answer now. Encryption is a way to protect sensitive data by making it harder to read the data. It basically has to prevent that people can look at it and immediately recognize it. Encryption is thus a very practical solution to hide data from plain view but it doesn’t stop machines from using a few extra steps to read your data again. Encryption can be very simple. There’s the Caesar Cipher which basically shifts letters in the alphabet. In a time when most people were illiterate, this was actually a good solution. But nowadays, many people can decipher these texts without a lot of trouble. And some can do it just inside their heads without making notes. Still, some people still like to use ROT13 as a very simple encryption solution even though it’s almost similar to having no encryption at all. But combined with other encryption methods or even hashing methods, it could be making encrypted messages harder to read, because the input for the more complex encryption method has already a simple layer of encryption. Encryption generally comes with a key. And while ROT13 and Caesar’s Cipher don’t seem to have one, you can still build one by creating a table that tells how each character gets translated. Than again, even the mathematical formula can be considered a key. Having a single key will allow secret communications between two or more persons and thus keep data secure. Every person will receive a key and will be able to use it to decrypt any incoming messages. These are called symmetric-key algorithms and basically allows communication between multiple parties, where each member will be able to read all messages. The biggest problem of using a single key is that the key might fall into the wrong hands, thus allowing more people access to the data than originally intended. That makes the use of a single key more dangerous in the long run but it is still practical for smaller sessions between multiple groups, as long as each member has a secure access to the proper key. And the key needs to be replaced often. A single key could be used by chat applications where several people will join the chat. They would all retrieve a key from a central environment and thus be able to read all messages. But you should not store the information for a long time. A single key can also be used to store sensitive data into a database, since you would only need a single key to read the data. A more popular solution is an asymmetric-key algorithm or public-key algorithm. Here, you will have two keys, where you keep the private (master) key and give others the public key. The advantage of this system is that you can both encrypt and decrypt data with one of the two keys, but you can’t use the same key to reverse that action again. Thus it is very useful to send data into a single direction. Thus the private key encrypts data and you would need the public key to decrypt it. Or the public key encrypts data and you would need the private key to decrypt it. Using two keys thus limits communication to a central hub and a group of people. Everything needs to be sent to the central hub and from there it can be broadcasted to the others. For a chat application it would be less useful since it means the central hub has to do more tasks. It needs to continuously decrypt and encrypt data, even if the hub doesn’t need to know the content of this data. For things like email and secure web pages, two keys is practical, though. The mail or web server would give the public key to anyone who wants to connect to it so they can encrypt sensitive data before sending it to the server. And only the server can read it by using the private key. The server can then use the private key to encrypt new data and send it to the visitor, who will use the public key to decrypt the message again. Thus, you have secure communications between two parties. Both methods have some very secure algorithms but also some drawbacks. Using a single key is risky if that key falls into the wrong hands. One way to solve this is by sending the single key using a two-key algorithm to the other side! That way, it is transferred in a secure way, as long as the key used by the receiver is secret enough. In general, that key should need to be a private key so only the recipient can read the single-key you’ve sent. A single key is also useful when encrypting files and data inside databases since it would only require one key for both actions. Again, you would need to store the key in a secure way, which would again use a two-key algorithm. You would use a private key to encrypt the single key and include a public key in your application to decrypt this data again. You would also use that public key inside your applications only but it would allow you to use a single public key in multiple applications for access to the same data. As I said, you need to limit access to data as much as possible. This generally means that you will be using various different keys for various purposes. Right now, many different encryption algorithms are already in use but most developers don’t even know if the algorithm they use is symmetrical or asymmetrical. Or maybe even a combination of both. Algorithms like AES, Blowfish and RC4 are actually using a single key while systems like SSH, PGP and TLS are two-key algorithms. Single-key algorithms are often used for long-term storage of data, but the key would have additional security to avoid easy access to it. Two-key algorithms are often used for message systems, broadcasts and other forms of communication because it is meant to go into a single direction. You don’t want an application to store both a private key and matching public key because it makes encryption a bit more complex and would provide a hacker a way to get the complete pair. And as I said, a single key allows easier communications between multiple participants without the need for a central hub to translate all messages. All the hub needs to do is create a symmetrical key and provide it to all participants so they can communicate with each other without even bothering the central hub. And once the key is deleted, no one would even be able to read this data anymore, thus destroying almost all traces of the data. So, what solution would be best for your project? Well, for communications you have to decide if you use a central hub or not. The central hub could archive it all if it stays involved in all communications, but you might not always want this. If you can provide a single key to all participants then the hub won’t be needed afterwards. For communications in one single direction, a two-key algorithm would be better, though. Both sides would send their public key to the other side and use this public key to send messages, which can only be decrypted by the private key which only one party has. It does mean that you actually have four keys, though. Two private keys and two public keys. But it happens to be very secure. For data storage, using a single key is generally more practical, since applications will need this key to read the data. But this single key should be considered to be sensitive thus you need to encrypt it with a private key and use a public key as part of your application to decrypt the original key again. In general, you should use encryption whenever you need to store sensitive data in a way that you can also retrieve it again. This is true for most data, but not always. In the next part, I will explain hashing and why we use it.
Petroleum geologists play a vital role in locating energy resources. They use a variety of methods to collect the data they need to find reservoirs of oil and natural gas. When they find these reservoirs, petroleum geologists need to calculate their volume. They also need to estimate how much they can recover (remove) from the reservoir. This helps them to determine the possible value of the discovery. By using a model, this investigation will help you to understand the physical relationships between natural gas, oil, and water in a reservoir and how these relationships can affect recovery. - 500 mL clear plastic soda bottle with cap - Supply of vegetable oil - Notebook and pen - Pour water into the soda bottle until the bottle is about half full. Add vegetable oil until the bottle is three-fourths full. Screw the cap tightly onto the bottle. The water, vegetable oil, and air in the model represent water, crude oil, and natural gas. The bottle itself represents an oil and gas reservoir. - Slowly turn the bottle upside down (if you shake the bottle or turn it quickly, you will make bubbles in the oil, which will interfere with your observations). In your notebook, sketch a diagram to represent the relationship between the oil, water, and air. Why do you think that the material stacks in the order that it does? - If a well is drilled into an oil and natural gas reservoir, what material would it encounter first? Second? Third? Record your ideas in your notebook. - Tilt the bottle at a 45-degree angle and hold it there. Repeat this with a 10-degree angle. Look at the bottle from the side, and then from the top. Draw a diagram of the side view of the bottle when it is tilted at a 45-degree angle versus a 10-degree angle. - How does the surface area covered by the oil change with the angle of the oil reservoir (bottle)? Imagine drilling a vertical well through the bottle. This represents a well being drilled into reservoirs that are sloping at different angles in the subsurface. Would the well penetrate a greater thickness of oil when the reservoir is at a 10-degree angle or when the reservoir is at a 45-degree angle? Why?
This free version of Animals Fun Learning Game is a simple and easy game for children to learn about 20 animals and for parents, guardians, or teachers to read along and interact with children. For ages 3 and up. Download the full version for 40 more animals! -Learn up to 20 animals by connecting their names to pictures. -Real animal pictures. -Interesting animal facts with some environmental awareness information, which you can read with children. -Sounds and music. -Recognize animals by names and pictures. -Learn through process of elimination skill development. -Develop reading and listening skills through clue connections and audio. -Develop environmental awareness at an early age. -Develop a sense of achievement through positive reward. -Tap the correct animal based on the clue. -Learn interesting facts about each animal. Tip: Here's a chance to read along with children! -See how many animals you can learn!
In this tutorial, I will show you different ways for how to remove character from string in python. So without wasting any time let’s get started. 1. Remove Character By Using Replace Method In this code example, we used the replace() method of string to substitute characters from it. # replace character from string in python >>> x = "abbaacccfag" # input string # Remove all 'a' from the string with empty string >>> x.replace("a","") 'bbcccfg' # remove newline from string python >>> "test \n 123 \n 456".replace("\n","") 'test 123 456' Set the count argument to remove only specific number of times. >>> x = "abbaacccfag" # input string # only remove first occuring 'a' >>> x.replace("a","",1) 'bbaacccfag' # only remove 2 a >>> 'bbacccfag' Also read about how to remove spaces from string in python 2. Remove Character From String In Python By Using For Loop In the below coding snippet, we used for loop to remove all characters from the string. Here is the algorithm. - First, we define an empty string. - Then we iterate through each character of the input string. - On each iteration, we check if the current character is not equal to the character to be removed, then add it to the string. - Return the final string to the user. def remove(string,element): """ Function to Remove Character From String In Python """ result = '' # define an empty string for i in string: # iterate through the string if i!= element: # if i is not equal element result += i # add to the string return result x = "abbaacccfag" print(remove(x,"a")) Here is the output of above code. That’s wrap for this tutorial.
Get even more great free content! This content contains copyrighted material that requires a free NewseumED account. Registration is fast, easy, and comes with 100% free access to our vast collection of videos, artifacts, interactive content, and more. With a free NewseumED account, you can: - Watch timely and informative videos - Access expertly crafted lesson plans - Download an array of classroom resources - and much more! - Civil War - As a class, make a list of reasons why news reports sometimes get facts wrong. Possible ideas: deadline pressure, limited manpower, sloppiness, biases leading to bad judgment, poor communication, bad information from sources, assumptions, etc. Explain that it’s important to accept that journalists will sometimes make mistakes, but that doesn’t mean we should accept sloppy reporting or allow news organizations to hide or ignore their failings. Getting it right is one of the core values of good journalism, and it’s partly up to us as consumers to hold the media accountable. - Hand out the Media Mix-Ups Through History worksheet and assign students one of the historical sources in the gallery on this page to analyze. They may work in teams, pairs or individually. You may choose to go over the E.S.C.A.P.E. Junk News poster to prepare students to employ its six ways to analyze an artifact: evidence, source, context, audience, purpose and execution. - When students have completed their worksheet, look at the historical sources in the gallery as a class and briefly explain what each one is. Then, present contemporary examples to the class for comparison and discuss the questions below. - Copies of the Media Mix-Ups Through History worksheet (download), one per student - Access to the gallery of historical sources on this page (either printed copies or via devices) - Contemporary examples of flawed reporting (possible examples can be found in the “Problematic” section of the Examples for Evaluating Online News download, or by searching for stories with published corrections) - E.S.C.A.P.E. Junk News poster (for reference, optional download) - Consider each example. What did it get wrong? Can you tell why this error happened? - What (if any) consequences do you think these errors could have had in the real world? - Could readers at the time of these articles have known that they were flawed? If so, how? If not, do you think they ever received the correct information? - Which of these errors could have been avoidable? How? Were any of them unavoidable? Why? - Why is it important to recognize mistakes when looking at historical sources? Why is it important when looking at present-day media? - How are these examples of errors in the news the same as/different from the mistakes we see today? Common Core State Standards: CCSS.ELA-LITERACY.CCRA.R.1Read closely to determine what the text says explicitly and to make logical inferences from it; cite specific textual evidence when writing or speaking to support conclusions drawn from the text. Common Core State Standards: CCSS.ELA-LITERACY.CCRA.R.2Determine central ideas or themes of a text and analyze their development; summarize the key supporting details and ideas. Common Core State Standards: CCSS.ELA-LITERACY.CCRA.SL.1Prepare for and participate effectively in a range of conversations and collaborations with diverse partners, building on others' ideas and expressing their own clearly and persuasively. Common Core State Standards: CCSS.ELA-LITERACY.CCRA.SL.2Integrate and evaluate information presented in diverse media and formats, including visually, quantitatively, and orally. Common Core State Standards: CCSS.ELA-LITERACY.CCRA.W.1Write arguments to support claims in an analysis of substantive topics or texts using valid reasoning and relevant and sufficient evidence. NCSS C3 Framework: D2.His.4.6-8 and D2.His.4.9-126 - 8: Analyze multiple factors that influenced the perspectives of people during different historical eras. 9 - 12. Analyze complex and interacting factors that influenced the perspectives of people during different historical eras. ISTE: 3b. Knowledge ConstructorStudents evaluate the accuracy, perspective, credibility and relevance of information, media, data or other resources. National Council of Teachers of English: NCTE.1Students read a wide range of print and non-print texts to build an understanding of texts, of themselves, and of the cultures of the United States and the world; to acquire new information; to respond to the needs and demands of society and the workplace; and for personal fulfillment. Among these texts are fiction and nonfiction, classic and contemporary works.
Chronic crises and sudden disasters related to climate change disproportionately affect children. Not only do children make up almost half of the population in developing countries, and hence are one of the largest groups affected by climate change, but they also are one of the groups most vulnerable to climate change. For example, due to their physical immaturity, threats such as malaria and diarrhoea, hunger and malnutrition often result in much higher levels of illness and death among children, particularly those under the age of five. Every year in the next decade, the kinds of natural disasters brought about by climate change are likely to affect up to 175 million children. The impacts are diverse. Children are unable to attend school in disaster times and even beyond, as families send them out to work. Children are at greater risk of injury and suffer disproportionately from disease as water, sanitation and food security are threatened; and the psychological and social implications are high as children may be separated from parents, lose family members, be forced into early marriage, or suffer from violence and displacement because of disaster. The costs are also high. According to the World Health Organization (WHO) "climate change was estimated to be responsible in 2000 for approximately 2.4 per cent of worldwide diarrhoea, 6 per cent of malaria in some middle income countries and 7 per cent of dengue fever in some industrialized countries." The Stern Review further estimates that climate change could lead to an additional 250,000 child deaths per year. The response to the threat of climate change thus demands greater investment in a "child-centred" approach to adaptation. The focus here is on adaptation (rather than mitigation of emissions) because children are on the front line of vulnerability to climate change, and hence adaptation is key to protecting their lives and livelihoods. Many of the measures that can address children’s vulnerability to climate change are already well known, are some of the lowest cost measures available, and also able to bring about significant levels of benefit. There are three key economic arguments for investing in a child-centred approach: 1. Children are one of the largest groups at risk from climate change. Therefore, measures that specifically target this group have the potential to reduce the impacts of climate change across a large proportion of the population, and may realise economies of scale. Importantly, child centred measures lead to skill development across a large segment of the population and over a longer time period. The risk of a group of people to the effects of climate change impacts can be described in two components. The first component is the exposure of a group to the impacts of climate change. Save the Children estimates that children make up approximately 50 per cent of people affected by disasters. Hence, any measures that target children as a group have the ability to foster resilience in a large portion of the population, and may realise economies of scale. Similarly, those measures that are built around child participation are drawing on a large population for effecting change. 2. Children are also one of the groups most vulnerable to the effects of climate change. Therefore, the losses associated with degradation of health, education and protection caused by climate change are high. In turn, adaptation measures to protect children have the potential to offset these losses, and realise significant economic gains. The second component of risk is the vulnerability of the group exposed to the effects of climate change - in other words, populations will be most at risk to the effects of climate change where exposed groups have the least resilience to these changes. Children are clearly one of the groups most vulnerable to the effects of climate change. A UNICEF report highlights that children are particularly vulnerable because their physical characteristics, childhood activities and natural curiosity put them at greater risk from environmental hazards. They are more susceptible to disease, and are more likely to die from climate related disease. If they survive, the impacts of disease can be irreversible and have economic impacts that continue throughout life. Research findings increasingly point to the critical imprints that childhood health, nutrition, and education leave on long-term adult mental and physical health and the ability to contribute to a sustainable society. As a result of children being highly vulnerable, the potential losses associated with climate change and disaster impacts are high. It stands to reason that where climate change losses are high, measures that avoid those losses result in significant economic gains. In addition, these gains are likely to be realised over a longer time frame: where children are proactively involved in adaptation and disaster risk reduction activities, they carry that knowledge and learning with them for life and, because they are young, the benefits of that learning will be realised over more years than an older counterpart. 3. Many of the interventions that can reduce the vulnerability of children to climate change are some of the lowest cost options and are already well established, such as insecticide treated mosquito nets, and water, sanitation and hygiene training. Clearly, there is a wide array of adaptation options that can be taken to protect populations from the effects of climate change. In some cases, the options required are high cost, for example structural measures such as building dykes and dams to protect shorelines from sea-level rise and other extreme events. However, in the case of children, many of the actions required are simple and low cost, such as mosquito nets, water and sanitation interventions, and treatment of diarrhoea. There is clear evidence that investment in climate change adaptation and disaster risk reduction will build resilience, and that in the vast majority of cases the investments can represent value for money. This is only accentuated for child-centered initiatives, where the benefits may be significantly amplified, for the reasons mentioned above. However, it is increasingly clear that many initiatives that are value for money in principle, are not yielding their intended benefits in practice. Interventions are all too often implemented in isolation from each other, with a strong sectoral focus, and a short-term investment horizon. Community involvement and ownership can be lacking, and the overall effect is that well-intentioned interventions fail to deliver their intended benefits over even a short term. Further, as the international community strives towards defining and developing community "resilience" - in other words facilitating the ability of a community to cope and manage change on their own in the face of a shock or stress - such a perspective demands a holistic and coordinated approach to development, to achieve transformational change. (1) Save the Children, Legacy of Disasters: The impact of climate change on children, 2007. (2) World Health Organization, The World Health Report 2002: Reducing risks, promoting healthy life, 2002. (3) Stern, N., Stern Review on the Economics of Climate Change, HM Treasury, London, 2006. (4) Save the Children, 2007. (5) UNICEF, Climate Change and Children: A human security challenge, 2008. (6) Children in a Changing Climate (CCC) coalition, Children and Disasters: Understanding Impact and Enabling Agency, 2011.
The Art & Science of Web Design \| 4 The Art & Science of Web Design The History of Electronic Text Historically, when a printed manuscript was given to a copy editor for grammatical and formatting edits, the process would include something called "markup." In the case of, say, a turn-of-the-century newspaper, an editor would scribble codes in the margins of a particular story that described how it should look. Then the codes were interpreted by a typesetter (the person who was responsible for putting together the final page on the press). Headlines, for example, would be marked with a shorthand notation describing which typographical convention to use. Thus, the editor might write something like "TR36b/c" and point to the first line of text on a page, effectively telling the typesetter to set that line as a headline in Times Roman 36 point bold and centered. Most publications, however, defined standards for each individual part of a story and page. That way, the editor wouldn't need to write the same typographic codes again and again. Instead, each page element could simply be specified by name. Not only did this save time, but it ensured consistency across a publication. A newspaper, for example, might have defined six different headline weights to correspond to a story's position on a page. The paper's editor could save time when doing the layout by tagging a story's first line of text with a standard notation like "HEAD3". A typesetter, encountering the notation, would look up the code on a sheet listing the style standards, and format the headline accordingly. This process is known as indirection-a concept that would eventually find its way into all aspects of publishing as well as disciplines like computer science. Early computer word-processing applications followed a similar evolution. Much like copyeditors adding formatting codes, these tools processed text with specific markup. The user was able to denote text with instructions that would describe how the text should be presented: whether bold, italic, big, or small. While this may have been fairly interesting in an abstract historical context, it was ground-breaking to the handful of researchers like Charles Goldfarb in the late 1960s. They began to realize that using typographical conventions in word processors was shortsighted. Rather, they believed electronic text should be tagged with general markup, which would give meaning to page elements much like the markup codes traditionally shared between editors and typesetters. By separating the presentation of a document from its basic structural content, the electronic text was no longer locked into one static visual design. Charles experimented with storing his electronic legal briefs in pieces, and labeling each piece of the brief based on what they were, rather than what they should look like. Now, instead of marking a chunk of text as being 36pt Times Roman, he could simply label it as "Title." The same could be done for every other chunk in the document: author, date published, abstract, and so forth. When thousands of briefs had been marked up with standard tags, you could start to do some amazing things such as grouping summaries of briefs written by a particular lawyer, or collapsing a document down to a simple outline form. Then, when you were satisfied with the final brief, you could print the document by specifying a style sheet much like editors and typographers did decades ago. Each tag was assigned a particular formatting style, and the document was produced in a physical form. Updating, redesigning, and republishing was a breeze. Charles was no longer bored. Technology and publishing had intersected in a remarkably powerful way. Charles Goldfarb continued his work at IBM into the early 1970s with Edward Mosher and Ray Lorie. As they researched their integrated law office information systems, they developed a system of encoding information about a document's structure by using a set of tags. These tags followed the same basic philosophy of representing the meaning of individual elements, with the presentation then applied to structural elements rather than the individual words. The team started to abstract the idea. Rather than develop a standard set of tags, why not just set up the basic rules for tagging documents? Then every document could be tagged based on its own unique characteristics, but the searching, styling, and publishing of these documents could all be done with the same software, regardless of whether you were sending out legal briefs or pages of a newspaper. They dubbed their system the Generalized Markup Language, or GML (which, incidentally, also encoded the initials of the inventors for posterity). And here's the interesting part: GML was developed so it could be shared by all electronic text. If there was a standard method for encoding content-the reasoning went, then any computer could read any document. The value of a system like this would grow exponentially. The concept quickly spread from the confines of IBM. The publishing community realized that by truly standardizing the methodology of GML, publishing systems worldwide could be developed around the same core ideas. For years, researchers toiled over the best way to achieve these goals, and by the mid-1980s, the Standard Generalized Markup Language, or SGML, was finished. The resulting specification, known to the world as ISO 8879, is still in use today. SGML successfully took the ideas incorporated into GML much further. Tags could go far beyond simple typographic formatting controls. They could be used to trigger elaborate programs that performed all sorts of advanced behaviors. For example, if the title of a book was tagged with a <book> tag, an SGML system could do much more than simply make the text italic. The book tag could trigger code in the publishing system to look up an ISBN number, and then create a bibliographic reference including the author, publisher, and other information. SGML could also be used to generate compound documents, which are electronic documents that are pulled together automatically from a number of different sources. A document no longer needed to be a collection of paragraphs, but could include references to information in a database that could be formatted on the fly. Consider the statistics on the sports page of a newspaper; raw data flows through formatting rules to automatically generate the daily page; or imagine a catalog that always printed the current prices and inventory data from a warehouse. Electronic publishing began to come of age. As a standard, SGML was a remarkable accomplishment. Getting thousands of companies, organizations, and institutions to agree on a systematic way of encoding electronic documents was revolutionary. The problem, however, was that in order to be universally inclusive, SGML ended up being massively complicated. So complicated, in fact, that the only real uses of the language were the largest constituents of the standards group: IBM, the Department of Defense, and other cultivators of massive electronic libraries. SGML was a long way away from the desktops of emerging personal computers at the time. Revised: March 20, 2001 Created: March 20, 2001
Online Unplugged lesson plan showing the wearable technology used by cyclist for safety, we will also introduce participant to the ways of building such technology using microcontrollers. We will be introducing the participant to what we will do in the session, Also, we will break the ice in between to encourage them to interact. 1- We will start by an ice breaking question: “What do you think about cycling safety” 2- Then we will mention the cycling as a general definition for them. 3- After that we will discuss the safety meaning and the advantages of making safety as a first priority. 4- Then we will mention the new technology equipment’s that have been used lately in the field of cycling.
Artificial sweeteners are used by millions of people all around the world to treat obesity, but it is also a great way to stimulate appetite, as per a new research. However, it should be mentioned here that people do not quite know their full impact on the brain and how they play a part in regulating hunger. The conclusion was based on a study which was published in the journal ‘Cell Metabolism’ and it throws light on the different effects of artificial sweeteners on the brain in regulating appetite and how they play a role in altering taste perceptions. This report suggests that researchers from the University of Sydney’s Charles Perkins Centre and the Garvan Institute of Medical Research have come across a new system in the brain which is responsible for sensing and integrating the sweetness and energy content of the food. “After chronic exposure to a diet that contained the artificial sweetener sucralose, we saw that animals began eating a lot more,” said lead researcher and Associate Professor Greg Neely from the University of Sydney’s Faculty of Science. “Through systematic investigation of this effect, we found that inside the brain’s reward centres, sweet sensation is integrated with energy content. When sweetness versus energy is out of balance for a period of time, the brain recalibrates and increases total calories consumed,” added Associate Professor Neely. In order to arrive at the conclusion, fruit flies were exposed to a diet which was replete with artificial sweetener for extended periods. It was observed that they consumed 30 per cent more calories when they were exposed to naturally sweetened food. “When we investigated why animals were eating more even though they had enough calories, we found that chronic consumption of this artificial sweetener actually increases the sweet intensity of real nutritive sugar, and this then increases the animal’s overall motivation to eat more food,” said Associate Professor Neely.
Remembering: The Genesis of Black History Month The words of Dr. Carter G. Woodson best describe the reasons for the inception of Negro History Week, which he started in 1926. In the October 1927 edition of the Journal of Negro History, Dr. Woodson wrote: The celebration tends not to promote propaganda, but to counteract it by popularizing the truth. It is not interested so much in Negro History as it is in history influenced by the Negro; for what the world needs is not a history of selected races or nations but the history of the world void of national bias, race hate, and religious prejudice. There has been, therefore, no tendency to eulogize the Negro nor to abuse his enemies. The aim has been to emphasize important facts in the belief that facts properly set forth will speak for themselves. Dr. Woodson is the “Father of Black History.” In 1915, he founded the Association for the Study of Negro Life and History (ASNLH) and the next year published the first edition of the Journal of Negro History. The initiating of Negro History Week by Dr. Woodson was consistent with his commitment to institutionalizing the study and propagation of black history. It was probably in November of 1925 that Dr. Woodson thought to begin this celebration. During this time, he communicated with other influential African Americans, all of whom supported the idea. They then agreed on the second week of February for the observance of the achievements of the “Negro.” This week was chosen because it’s the week of Frederick Douglass and Abraham Lincoln’s birthday and both of them were highly respected at that time. Through the support of educators, ministers, and community leaders around the country, the first Negro History Week was a success. Each group and institution was left to its own initiative in working out a program particular to their local needs. This first observance included community speaker forums, discourses on Black history, and school plays portraying heroes in Black history. Special programs were also conducted by social welfare agencies, business organizations and recreational establishments. The celebration was generally observed by African Americans, however, there were integrated schools that participated. During the 1960s the use of “Black” and “Afro-American” replaced the popular use of “Negro.” At the 1972 Convention of the ASNLH held in Cincinnati, Ohio, pressure from young delegates forced the organization to change its name to the Association for the Study of Afro-American Life and History (ASALH). Negro History Week was then changed to Black History Week. During America's Bicentennial celebration in 1976 the ASALH joined the nation in its focus on American history and decided to expand the observance of Black History Week to include the entire month of February. This was done to provide time for more activities focusing on the vast contributions of Blacks to the history of America. The observance was so successful that the association decided to continue its monthly celebration. The need for Black History Month has not diminished since the inception of Negro History Week in 1925. Dr. Woodson's rationale for the celebration remains relevant even into the 21st century. The contributions of African people continue to be misrepresented or not represented in history. Unfortunately, there are many white Americans who have greatly benefited from misinformation and lies about black people. The belief that the African was of an inferior race gave justification to chattel slavery. Through the use of slave labor, America was built largely by people who never reaped the benefits of even being recognized as citizens. Slavery created a tremendous disadvantage for black people mentally and economically. Yet, it created great benefits for whites and their descendants. The debunking of religious, scientific, historical and philosophical misinformation about Blacks has continued into the 21st century. The history of African Americans may one day become a recognized part of American heritage. Perhaps, all American children will soon be taught about the great black athletes, scientists, inventors, artists, politicians, educators, entrepreneurs, explorers, ministers, and soldiers, just as black children are always taught of whites in these areas. A true and objective presentation of history eliminates the foundation of racism for some and increases the self-esteem of others. The observance of Black History Month must lead to the day when the history of the world will be void of national bias, race hate and religious prejudice. How to Celebrate Black History Month African Heritage - 1st Week: During the first week celebrations should focus on the contributions of Africans to world history. Attention must be given to the fact that all races came from African ancestors and that Kemet (Egypt) is the cradle of civilization. We must also remember how the wealth taken from Africa by colonial powers through exploitation of the people, minerals and land made the Western World powers quite rich. Our African heritage should be honored through our giving financial support to impoverished African nations and by supporting the anti-colonial movements in Africa. By paying this tribute, we show our respect for our African heritage and our commitment to the future of the Mother Continent. African Holocaust - 2nd Week: During the second week memorial programs should be held to remember the tens of millions of Africans who died as a result of the slave trade and racism in America. They died fighting against slavery in Africa, died in slave ships in the Middle Passage, died in chattel slavery, died revolting against slavery in America, died from lynching, died in race riots that have taken place in hundreds of American cities, died from police brutality, died from chemical warfare (e.g., AIDS), and they died from alcohol, tobacco, and other drugs pushed in our communities. Families must honor the memory of their known and unknown ancestors who died in America. The children of the family must be told about their ancestors who have already passed on, especially those who died fighting for freedom. Great Heroes and Heroines - 3rd Week: During the third week we must pay tribute to the many men and women of distinction in Black history. We must remember the great educators, abolitionists, inventors, scientists, entrepreneurs, athletes, artists, entertainers, ministers, soldiers, and others of our past. Children should portray their heroes and heroines by acting in plays and skits. Adults could have fun honoring theirs by holding costume parties and dressing in the likeness of their heroes and heroines. Rites of Passage - 4th Week: The last week should be used as an opportunity for the men and women of the community to conduct Rites of Passage Programs for young boys and girls. This is a process of taking youth into adulthood by training them on their history, morals, values, spirituality, sexuality, economics, and responsibilities to their family. This training may be designed to pass on family, religious and/or cultural values. The training should be segregated by gender and the youth should be between 12 to 17 years old. The passage may take several hours or even days. At the completion of the rites, the new adult should be given something of value to signify their passing into adulthood. James C. Anyike, Author African American Holidays: A Historical Research and Resource Guide to Cultural Celebrations
Classics in the History of Psychology An internet resource developed by Christopher D. Green (Return to index) By Francis Bowen (1860) First published in Memoirs of the communicated March 27, April 10 and Reprinted in G. Daniels (Ed.) (1968). Darwinism comes to Posted May 2004 [Note from the Daniels edition: In the omitted portion of this article, Bowen reduced the Darwinian theory into the five assertions of ·which he said it consisted. The first two, the fact that individuals vary, and the fact that variations could be inherited, Bowen was ready to grant with only minor reservations. His real criticism begins with the third point.] 3. But with whatever success the doctrine of Inherited Variation may be applied to explain the existence of Varieties, it is certain that the origin of Species can be accounted for on the Development Theory, if at all, only by Cumulative Variation, -- that is, only by supposing a vast number of Inherited Variations to be successively superinduced one upon another. Doubts have been raised upon this point only on account of ambiguity in the meaning of words, or from want of agreement as to the principles of classification. Many races, both of animals and vegetables, appear to be so nearly allied to each other, that certain naturalists consider them as mere Varieties; others persist in considering them as so many distinct Species. Mr. Darwin himself remarks that the distinction between Varieties and Species is "entirely vague and arbitrary";… Fortunately we do not need, so far as our main question is concerned, to enter into the intricacies of this discussion. The advocates of the Development Theory undertake to prove that all Species of animals, even those differing most widely from each other, "have descended from at most four or five progenitors, and plants from an equal or lesser number." Putting aside altogether, therefore, the much debated question whether the several races of men are only Varieties, or are so many distinct Species, and the same question with respect to dogs, there is no doubt that men and dogs belong respectively to different Species. And generally, putting aside the question whether the offspring of certain races when crossed are entirely sterile or only partially so, there is no doubt that animals or plants belong to distinct Species when they cannot be crossed or made to interbreed at all. It is enough to say, then, that only Cumulative Variation -- and that of a vast number of successive steps -- will account for the common origin of animals which will not copulate with each other, or of plants which cannot be crossed. Now, on this cardinal point, which contains the essence of the Development Theory, since all the other questions involved in it are of no substantive importance, so far as what may be called the Philosophy of Creation is concerned, the direct evidence fails altogether, and we are left exclusively to the guidance of conjecture and analogy and estimates of what is possible for all that we know to the contrary. It is not even pretended that we have any direct proof, either from observation or testimony, that two Species so distinct that they will not interbreed have yet sprung from common ancestors. On the contrary, Mr. Danvin's own supposition is, that the process of developing two entirely distinct Species out of a third is necessarily so gradual and protracted as to require a quasi eternity for its completion, so that only a small portion of it could have been accomplished during the limited period of man's existence upon the earth. In the absence of any direct proof, then, it remains to be inquired if there are sufficient grounds of probability, reasoning from analogy and the principles of inductive logic, for believing that all Species of animals and plants map have originated from three or four progenitors. In speaking of the amount and frequency of Individual Variation, Mr. Darwin and his followers abuse the word tendency. After heaping up as many isolated examples of it as they can gather, they assert the legitimate inference from such cases to be, that the Species tends to vary, leaving out of view the fact that a vastly larger number of individuals of the same Species do not vary, but conform to the general type. And though only one out of a hundred of these Individual Variations is transmitted by inheritance, yet, after collecting as many instances of such transmission as they can find, they affirm that a Variation tends to become hereditable. But it is not so. Tendency is rightly inferred only from the majority of cases; a small minority of favorable instances merely shows the tendency to be the other way. Thus, the cars do not tend to run off the track, although one train out of a thousand may be unlucky enough to do so; but the general law is, that they remain on the track. Otherwise, people would not risk their lives in them.... The advocates of the Development Theory violate the first principles of inductive logic, by founding their induction not, as they should do, on the majority -- the great majority -- of cases, but on the exceptions, the accidents. Their whole proceeding is an attempt to establish a philosophy of nature, or a theory of creation, on anomalies, -- on rare accidents, -- on lusus naturae. This single objection is fatal to Mr. Darwin's theory, which depends on the accumulation, one upon another, of many successive instances of departure from the primitive type. For if even Individual Variation appears only in one case out of a hundred, -- and all naturalists will admit this proportion to be as large as the facts will warrant, -- and if, out of the cases in which it does appear, not more than one in a hundred is perpetuated by inheritance, then should a second Variation happen, what chance has it of leaping upon the back of one of the former class: The chance is one out of 100 X 100 X 100 = 1,000,000. And the chance of a third Variation being added to a second, which in turn has been cumulated upon a first, will be one out of 100 raised to the fourth power, or 100,000,000. It is not necessary to carry the computation any further, especially as Mr. Darwin states that the process of development can be carried out "only by the preservation and accumulation of infinitesimally small inherited modifications." Of course, the interval between two Species so distinct that they will, not interbreed could be bridged over only by a vast number of modifications thus minute; and on this calculation of the chances, the time required for the development of one of these Species out of the other would lack no characteristic of eternity except its name. But the theory requires us to believe that this process has been repeated an indefinite number of times, so as to account for the development of all the Species now in being, and of all which have become extinct, out of four or five primeval forms. If the indications from analogy, on which the whole speculation is based, are so faint that the work cannot have been completed except in an infinite lapse of years, these indications practically amount to nothing. The evidence which needs to be multiplied by infinity before it will produce conviction, is no evidence at all. 4. What is here called the "Struggle for Life" is only another name for the familiar fact, that every Species of animal and vegetable life has its own Conditions of Existence, on which its continuance and its relative numbers depend. Remove any one of these Conditions, and the whole Species must perish; abridge any of them, and the number of individuals in the Species must be lessened. The intrusion of a new race which is more prolific, more powerful, more hardy, or in any way better adapted to the locality, may gradually crowd out some of its predecessors, or restrict them within comparatively narrow bounds. Thus the introduction of the Norway rat has banished the former familiar plague of our households and barns from many of its old haunts, and probably reduced the whole number in this Species to a mere fraction of what it once was. Civilized man also has successfully waged war against many ferocious or noxious animals, and probably exterminated some of them. But the appearance of a rival or hostile race is not the only cause of such diminution or extinction. A change in the physical features of a given district may partially or entirely depopulate it, without the necessary introduction of any new-comers. The drying up or filling up of a lake is necessarily fatal to all its aquatic tribes. The gradual submergence of an island or a continent must exterminate, sooner or later, all the native Species which were peculiar to it. And at the utmost, the failure of any Condition of Existence, whatever may be its character, only leaves vacant ground for the future introduction or creation of new forms of life, without tending in the slightest degree to bring such new forms into existence. 5. Natural Selection, also, as already remarked, has nothing to do with the origin of Species, and, in its abstract form, is only the statement of a truism. Of course, when two or more Species crowd each other, the more prolific or the more vigorous, other things being equal, is more likely to gain possession of the disputed ground, and thus to diminish the numbers of the other or oblige it to migrate, or, in rare cases, to kill it out altogether. But this last supposition is a conceivable rather than a probable result. All observation goes to show, that every Species retains a very persistent hold upon life, however feeble may be the tenure of existence for its individual members. Its numbers may be materially diminished; it may be forced to shift its ground, and to suffer in consequence some slight change in its habits; (Mr. Darwin himself tells us of upland geese and of woodpeckers where there are no trees); it may be driven into holes and corners; but somehow it still survives. Utter extinction of a Species is one of the rarest of all events; not half a dozen cases can be enumerated which are known to have taken place since man's residence upon the earth. And these, surely, are a very insufficient basis on which to found a theory embracing all forms of life. Yet man is the greatest exterminator the world has ever known. His physical powers, coupled with the use of reason by which they are multiplied a thousand-fold, enables him to wage internecine war with comparative ease against nearly every race that molests him. Only the insect tribes, through their immense numbers and their littleness, can successfully defy him; and these not always. In his Struggle for Life, all other creatures, animal or vegetable, must retreat or perish. Yet how few has he rooted out altogether! But the Development Theory requires us to believe that this process of extinction, guided by Natural Selection, has been repeated well-nigh to infinity. Not only all the races which are now found only in their stone coffins, but countless others,-"the interminable number of intermediate forms which must have existed" as connecting links, and a still greater crowd of other Varieties not intermediate, but gross, rude, and purposeless in their formation, -- the unmeaning creations of an unconscious cause, -- must all have perished, each through its own peculiar repetition of a series of events so infrequent that we can hardly compute the chances of their happening at all. It is easy to see why the extermination of a Species, even upon the conditions of Mr. Darwin's theory, should be so infrequent. He holds that all the races which have originated upon the earth since the primeval act of creation first grudgingly threw only four or five seeds of existence into the ground, have been shaded into each other by gradations so slight as to be nearly imperceptible. Differing so slightly from each other, the advantage possessed by any one of them in the Struggle for Life must have been almost indefinitely small. But a peculiarity important enough to preserve those who have it, while whole Species must die out because they have it not, cannot be thus trifling in character. It must have been one of grave moment; not a slight Variation, but a jump. The successive development of new races -- itself, as we have seen, an extremely slow process -- must have been continued through numerous steps before the divergence resulting from it could have been serious enough to enable one of the divergent stocks to overcome and exterminate the other. Numerous Species of the same genus now coexist, often within the bounds of a not very extended territory, without any one of them showing any tendency to supplant or exterminate another. Thus, South Africa is the country par excellence of the antelope; about fifty species of this animal have been found there, many of them very abundant, notwithstanding the numerous Carnivora that prey upon them, and yet none of them showing any tendency to die out before civilized man came thither and brought gunpowder along with him. Natural Selection can operate only upon races previously brought into being by other causes. In itself, it is powerless either to create or exterminate. In the Development Theory, its only function is, when the number of different Species is so far multiplied that they crowd upon each other, and the extinction of one or more becomes inevitable (if we can conceive of such a case), then to make the selection, or to determine which shall be the survivors and which the victims. As individuals of the same Species, the same Variety, and even of the same flock, certainly differ much from each other in strength, swiftness, courage, powers of endurance, and other qualities, Natural Selection has an undoubted part to play, when the struggle comes for such a flock, in determining which of its members shall succumb. But that it ever plays a corresponding part in the grand contest of Species imagined by Mr. Darwin, is a supposition resting upon no evidence whatever, but only upon the faint presumption afforded by the fact, that certain Species at widely separated times have become extinct, through what causes we know not; and therefore, for all that we know to the contrary, Natural Selection may have had something to do with their disappearance. This is to found a theory, not upon knowledge, but upon ignorance. If such reasoning be legitimate, we are entitled to affirm that the moon is inhabited by men "whose heads do grow beneath their shoulders." It may be so, for all we know to the contrary. This review of the state of the evidence upon each of Mr. Darwin's five points is enough to show that the testimony fails entirely just where it is most wanted. Facts and arguments are accumulated where they are of little or no avail, because the conclusions to which they tend, when properly limited and qualified, are admitted and familiar principles in science. But the theory of the Origin of Species by Cumulative Variation which is all that is peculiar to this form of the transmutation hypothesis, rests upon no evidence whatever, and has a great balance of probabilities against it. Individual Variation, the Struggle for Life, and Natural Selection, each within clearly defined limits, are acknowledged facts, which still leave the main question in the philosophy of creation precisely where it was before; and even the doctrine of Inherited Variation relates only to the origin of Varieties, which is a distinct question, and one of subordinate importance and interest, except to naturalists. Mr. Darwin has invented a new scheme of cosmogony, and finds that, like other cosmogonies, it is a blank hypothesis, not susceptible either of proof or disproof, and needing an eternity for its development. There is nothing new in such a speculation of what is possible in an infinite lapse of years. This latest form of the speculation has no advantage over the one first propounded some three thousand years ago; -- that a chaos of atoms, moving about fortuitously in infinite space, may have happened, in an eternity, to settle into the present kosmos; for the chance of order and fitness is at least one out of an infinite number of chances of disorder and confusion; and in an infinite series of years, this solitary chance must sooner or later be realized.... Every such speculation must be rejected, because it is self-contradictory. It professes to develop a Theory of Creation, -- to explain the beginning of things; and in order to do so, it is obliged to assume that the present or ordinary succession of phenomena, the common sequence of causes and effects which we every day witness, has continued from eternity; -- that is, that there never was any Creation, and that the universe never began to be. It professes to untie the knot, and ends by denying that there is any knot to untie. Mr. Darwin is too imaginative a thinker to be a safe guide in natural science; he has unconsciously left the proper ground of physics and inductive science, and busied himself with questions of cosmogony and metaphysics.
The Prang color system is the basis of the artist's color wheel, and it uses red, blue and yellow as its primaries. This system theorizes that the three primary colors can't be produced by mixing other hues, but can produce all other hues through mixing two of the primaries together. Developed by Louis Prang, the Prang color system is most often used by artists in determining what paint pigments to mix in order to produce desired colors out of the basic primary colors. Many other color systems are used. Printers rely on the process color system, which uses cyan, magenta, yellow and black as its primary colors. Televisions, computer monitors and other devices that project light to represent color use the additive system, which mixes red, blue and green primary colors.
Avascular necrosis, or osteonecrosis, is the name given to bone death, a condition that occurs when… What is ankylosing spondylitis? Ankylosing spondylitis is a form of inflammatory arthritis. It affects the joints of the spine, in particular the sacroiliac joint at the bottom of the spine. Ankylosing spondylitis causes the swelling of the ligaments, discs and joints between the vertebrae of the spine. Symptoms include pain and stiffness in the lower back and over time, fusion of the vertebrae can occur. The specific cause of ankylosing spondylitis is unknown, although genetic factors appear to play a role. The presence of a specific gene that produces the antigen HLA-B27, is found in nine out of 10 people with ankylosing spondylitis, although there are people with the gene that do not develop the condition. It is therefore thought that other factors are involved in triggering ankylosing spondylitis. Ankylosing spondylitis can begin to develop from the age of 15 years and generally affects young adults before the age of 35 years. The condition begins with inflammation of the sacroiliac joint and facet joint. Over time, bony growths can begin to form and cause fusion of vertebrae, causing limited movement and pain in the lower back. Risk factors associated with developing the condition include: Signs and symptoms The signs and symptoms of ankylosing spondylitis include: - Lower back pain that gradually appears over time, is worse after rest and improves after exercise; - Stiffness that worsens in the morning; - Buttock, hip or shoulder pain; - Limited mobility of the spine; - Head-forward posture or neck pain; - Pain in ligaments and tendons that are attached to the spine, for example, the back of the heel, and; - Eye pain, light sensitivity or blurred vision. The signs and symptoms can improve, worsen, or stop entirely at irregular intervals. Methods for diagnosis Identifying ankylosing spondylitis early is important in preventing any damage to the spine. In many cases there can be a delay of 5-7 years from the time symptoms first appear to when the condition is diagnosed. In addition to reviewing the medical history, diagnosis of ankylosing spondylitis can be determined by the following tests: - A physical examination; - An X-ray to identify any changes in bones and joints; - A computerised tomography (CT) scan to assist with early diagnosis; - A magnetic resonance imaging (MRI) scan to enable visualisation of the inflammatory changes in the spine; - Blood tests to check for evidence of inflammation, and; - Genetic testing to check for the presence of the HLA-B27-causing gene. Types of treatment Currently there is no cure for ankylosing spondylitis. The main goal of treatment is to maintain a good quality of life by managing the symptoms and reducing the progression of the condition. Treatments include medications, physiotherapy and surgery. Medications used in the treatment of ankylosing spondylitis include: - Non-steroidal anti-inflammatory drugs (NSAIDs) to reduce inflammation and control pain and stiffness; - Disease-modifying antirheumatic drugs (DMARDs), which can slow the progression of the condition; - Tumour necrosis factor (TNF) inhibitors to control inflammation, and; Physiotherapy is also commonly used to manage ankylosing spondylitis. This can include using specific exercises to reduce the pain and increase the strength and flexibility of the muscles and tendons in the affected area. Your doctor or physiotherapist can tailor an exercise program and other therapies, such as hydrotherapy, to help improve mobility of the spine. In most cases, surgery is not necessary, but can be utilised if there is extreme pain or joint damage. Joints can be surgically fused or repaired, depending on the location and degree of damage to a joint. In severe forms of ankylosing spondylitis, it is possible for sections of the spine to become fused, causing stiffness and immobility. This can cause the natural curves of the spine to straighten, forcing the body into a hunched position. The rib cage can also become stiff, which can reduce the capacity of the lungs and cause breathlessness. Osteoporosis is a common complication, which can increase the risk of sustaining a fracture. The prognosis can depend on how early the condition is diagnosed. In some cases, only mild symptoms are experienced at irregular intervals and full physical activity is possible. In other cases, symptoms can be more frequent and complications, including spinal fusion, can occur. Treatment with medications and physiotherapy are important, after a confirmed diagnosis, to achieve the best outcome. There are no specific ways to prevent ankylosing spondylitis. It is, however, possible to slow its progression and minimise risk of developing complications through early diagnosis and timely use of specific treatments.
Record-breaking atomic clocks precise enough to measure spacetime distortions Time might feel like something we've got a pretty good handle on, but scientists are trying to find new ways to measure it ever more accurately. In recent tests run by the National Institute of Standards and Technology (NIST), experimental atomic clocks have achieved record performance in three metrics, meaning these clocks could help measure the Earth's gravity more precisely or detect elusive dark matter. The NIST clocks are made up of 1,000 ytterbium atoms, suspended in a grid of laser beams. These lasers "tick" trillions of times per second, which in turn cause the atoms to consistently flicker between two energy levels like a metronome. Measuring these allows atomic clocks to keep time incredibly precisely, in some cases losing only a single second over 300 million years. But there's always room for improvement, in this case by adding thermal and electric shielding to the devices. By comparing two experimental atomic clocks, NIST scientists have now reported three new records in the devices at once: systematic uncertainty, stability and reproducibility. Systematic uncertainty refers to how accurately the clock's ticks match the natural vibrations of the atoms inside it. According to the team, the atomic clocks were correct to within 1.4 errors in a quintillion (a 10 followed by 18 zeroes). Stability is a measure of how much the clock's ticks change over time. In this case, the NIST clocks were stable to within 3.2 parts in 1019 (a 10 with 19 zeroes) over the course of a day. And, finally, reproducibility is measured by comparing how well two atomic clocks remain in sync. Checking the two clocks 10 times, the team found that the difference in frequency of their ticking was within a quintillionth. "Systematic uncertainty, stability, and reproducibility can be considered the 'royal flush' of performance for these clocks," says Andrew Ludlow, leader of the project. "The agreement of the two clocks at this unprecedented level, which we call reproducibility, is perhaps the single most important result, because it essentially requires and substantiates the other two results." In fact, this new level of precision means that the atomic clocks could help us measure gravity more precisely than ever before. Since gravity is known to distort the passage of time – famously demonstrated by the way atomic clocks tick slower in space than on the ground – the atomic clocks can work backwards from measuring time to measuring the effects of gravity. Applications for that include measuring the geoid – the Earth's gravitational shape – to within 1 cm (0.4 in), making it several times more precise than the current best technology. Atomic clocks could also help detect gravitational waves, which are ripples in the very fabric of spacetime caused by cosmic cataclysms. They could even help out in the hunt for dark matter, which is so far only known through its gravitational interactions. The research was published in the journal Nature.
This book compares the two computer algebra programs, Maple and Mathematica used by students, mathematicians, scientists, and engineers. Structured by presenting both systems in parallel, Mathematica's users can learn Maple quickly by finding the Maple equivalent to Mathematica functions, and vice versa. This student reference handbook consists of core material for incorporating Maple and Mathematica as a working tool into different undergraduate mathematical courses (algebra, geometry, calculus, complex functions, special functions, integral transforms, mathematical equations). Part I describes the foundations of Maple and Mathematica (with equivalent problems and solutions). Part II describes Mathematics with Maple and Mathematica by using equivalent problems.
Plants buy Earth more time as CO2 makes them grow Trees and plants are growing bigger and faster in response to the billions of tons of carbon dioxide released into the atmosphere by humans, scientists have found. The increased growth has been discovered in a variety of flora, ranging from tropical rainforests to British sugar beet crops. It means they are soaking up at least some of the CO2 that would otherwise be accelerating the rate of climate change. It also suggests the potential for higher crop yields. Some researchers believe the phenomenon is strong enough to buy humanity some extra years in which to try to reverse the growth of greenhouse gas emissions. However, few dispute that this will provide anything more than a temporary reprieve. "There is no doubt that the enrichment of the air with CO2 is increasing plant growth rates in many areas," said Professor Martin Parry, head of plant science at Rothamsted Research, Britain's leading crop institute. “The problem is that humans are releasing so much that plants can remove only a fraction of it.”ĚCO2 Plants survive by extracting CO2 from the air and using sunlight to convert it into proteins and sugars. Since 1750 the concentration in the air has risen from of CO2 278 parts per million (ppm) to more than 380ppm, making it easier for plants to acquire the CO2 needed for rapid growth. One of the most convincing confirmations of this trend, recently published in the science journal Nature, came from a team at Leeds University. Simon Lewis, a fellow of the Royal Society, led the study that measured the girth of 70,000 trees across 10 African countries and compared them with similar records made four decades ago. "On average, the trees were getting bigger faster," Lewis said. He found that each hectare of African forest was trapping an extra 0.6 tons of CO2 a year compared with the 1960s. If this is replicated across the world’s tropical rainforests they would be removing nearly 5 billion tons of CO2 a year from the atmosphere. Humans, however, generate about 50 billion tons of the gas each year. Scientists have been looking for a similar impact on crop yields and have carried out experiments where plants growing in the open are exposed to extra CO2 released upwind of the site. The experiments generally suggest that raised CO2 levels, similar to those predicted for the middle of this century, would boost the yields of main-stream crops, such as maize, rice and soy, by about 13%. Some niche crops, such as lavender, would similarly benefit.
‘Solid as a rock.’ Have you heard someone say that before? Rocks have a reputation for being solid, hard, and indestructible. Rocks line river beds and jut above the landscape as mountain peaks; they are fun to collect and sometimes are very beautiful. Each rock is different – some are smooth and round, some are sharp and dangerous. They come in all colors: pink, green, orange, white, red. They are everywhere, and we take their presence for granted and assume that they are unchangeable. But rocks are not unchangeable! Just like the water cycle, rocks undergo changes of form in a rock cycle. A metamorphic rock can become an igneous rock, or a sedimentary rock can become a metamorphic one. Unlike the water cycle, you can’t see the process happening on a day-to-day basis. Rocks change very slowly under normal conditions, but sometimes catastrophic events like a volcanic eruption or a flood can speed up the process. So what are the three types of rocks, and how do they change into each other? Keep reading to find out! Three types of rock: Igneous rocks are formed when hot magma (melted rock) is rapidly cooled, either by hitting underground air pockets or by flowing from the mouth of a volcano as lava. Granite, obsidian, and pumice are all common examples of igneous rocks. Pumice is a very porous rock, because when the lava cooled, pockets of air were trapped inside. Because of all those air pockets, pumice can actually float! Sedimentary rocks are formed by layers of sediment (dirt, rock particles, etc.) being mixed and compressed together for extended periods of time. Common examples of these rocks are limestone, sandstone, and shale. Sedimentary rocks often have lots of fossils in them because plants and animals get buried in the layers of sediment and turned into stone. Metamorphic rocks are a combination of rock types, compressed together by high pressure and high heat. They usually have a more hard, grainy texture than the other two types. Schist, slate, and gneiss (pronounced like ‘nice’) are metamorphic rocks. These rocks change over hundreds of years in the six steps of the rock cycle: - Weathering & Erosion. Igneous, sedimentary, and metamorphic rocks on the surface of the earth are constantly being broken down by wind and water. Wind carrying sand wears particles off rock like sandpaper. Rushing river water and crashing surf rub off all the rough edges of rocks, leaving smooth river rocks or pebbles behind. Water seeps into the cracks in mountain rocks, then freezes, causing the rocks to break open. The result of all this: large rocks are worn down to small particles. When the particles are broken off a rock and stay in the same area, it is called weathering. When the particles are carried somewhere else, it is called erosion. - Transportation. Eroded rock particles are carried away by wind or by rain, streams, rivers, and oceans. - Deposition. As rivers get deeper or flow into the ocean, their current slows down, and the rock particles (mixed with soil) sink and become a layer of sediment. Often the sediment builds up faster than it can be washed away, creating little islands and forcing the river to break up into many channels in a delta. - Compaction & Cementation. As the layers of sediment stack up (above water or below), the weight and pressure compacts the bottom layers. (Try making a stack of catalogs and watch how the bottom one gets squished as you add more on top – this is the same idea as the compaction of layers of sediment.) Dissolved minerals fill in the small gaps between particles and then solidify, acting as cement. After years of compaction and cementation, the sediment turns into sedimentary rock. - Metamorphism. Over very long periods of time, sedimentary or igneous rocks end up buried deep underground, usually because of the movement of tectonic plates. While underground, these rocks are exposed to high heat and pressure, which changes them into metamorphic rock. This tends to happen where tectonic plates come together: the pressure of the plates squish the rock that is heated from hot magma below. (Tectonic plates are large sections of the earth’s crust that move separately from each other. Their movement often results in earthquakes.) - Rock Melting. Can you imagine ‘rock hard’ rocks melting? That’s what they do in the depths of the earth! Metamorphic rocks underground melt to become magma. When a volcano erupts, magma flows out of it. (When magma is on the earth’s surface, it is called lava.) As the lava cools it hardens and becomes igneous rock. As soon as new igneous rock is formed, the processes of weathering and erosion begin, starting the whole cycle over again! See if you can find sedimentary, igneous and metamorphic rocks where you live. As you study them, think about how they have undergone many slow changes to become what they are. Draw a picture of the rocks you find and then draw a diagram of the whole rock cycle. Keep reading to see how you can experience the rock cycle process for yourself! Wind and water and blowing sand can, over time, rub away the rough edges of rocks, leaving smooth stones. In nature this is called ‘weathering.’ But weathering can happen at home, too! Many people use a rock tumbler to shape and polish the rocks they collect. A rock tumbler mixes the stones with several types of grit to rub away the roughness, just like rocks ‘tumbled’ with sand in an ocean or river. The results are smooth, shiny rocks. When people tumble gemstones (usually semi-precious ones they find), they can end up with beautiful colors and can even use the polished stones to make their own jewelry. A gem or a gemstone is any mineral that can be cut and polished for jewelry or other decoration. The most precious gems are chosen for their beauty, rarity, and durability. Semi-precious gems usually have one or two of these characteristics, but fall short in some area. Fluorite, for instance, is very beautiful but it is too soft and will scratch easily. Agate, quartz, and amethyst are other examples of semi-precious gems. Diamonds are gemstones that are considered very precious, and for good reason. Though they are made of carbon, one of the most common elements, diamonds are generally regarded as some of the most beautiful gemstones. They are relatively rare, because much diamond is not of jewelry quality. Diamond mines usually have 1 part diamond to 40 million parts other rock, but a diamond high-quality enough to be in an engagement ring is the product of the removal and processing of 200 to 400 million times its volume of rock! The diamond’s strongest point, however, is its durability. It is the hardest substance found in nature, four times harder than the next hardest natural substance, corundum (sapphire and ruby). The grit in a regular rock tumbler wouldn’t have much effect on a diamond! It also has the highest melting point, and conducts heat five times better than the second best element, silver. Starburst Rock Cycle Have you ever made a rock collection? Part of the fun is gathering as many different rocks as you can find. But even though rocks come in many different colors, shapes, and sizes, they all fit into one of three categories based on how they were formed. Learn about the rock cycle, the three main types of rocks, and what happens when rocks get so hot that they melt! What You Need: - Starburst candy (assorted colors) - Adult’s help - Heat source (like a toaster oven, hot plate, blow dryer, etc.) - Wax paper cut into a 6-8” square - Aluminum foil cut into a 8-10” square, or a weighing boat - Rock cycle chart What You Do: 1. Unwrap four different-colored Starburst candies. Have an adult use the scissors to help you cut each piece of candy into 9-12 pieces. 2. Pile up the the pieces and mix them around. 3. Next, rub your palms together back and forth quickly for several seconds. Then pick up the pile of candy and push the pieces together to form a ball. Your ball should look lumpy with the candy pieces visible. 4. Next, have an adult help you use your heat source to soften the lumpy ball of candy. Once it’s slightly heated but not too hot to handle, place it in the middle of your square of wax paper and fold the paper in half over it. 5. Once candy lump is inside the wax paper, it’s time to apply pressure. Some ideas include rolling it with a rolling pin, placing a pile of heavy books on top of it, stepping on it, or whatever else you can think of! After you’ve mashed it well, remove the candy blob from the wax paper and fold it up. Then put it back in the wax paper and repeat the process of applying pressure, this time trying a new technique, if you want. When you remove the Starburst from the wax paper now, it should be soft and pliable, so you can easily roll it into a ball. 6. If using foil, fold each side up to fashion a dish and place the candy blob inside. 7. Have an adult help you use your heat source to apply enough heat to completely melt the lump of candy. You’ll know you’ve heated it sufficiently when the candy is liquified. (Do not put aluminum in a microwave!). 8. Have an adult use tongs to remove the foil container from the heat source and place it somewhere out of reach to allow it to cool. 9. Once it’s cool enough to handle, carefully peel the candy from the foil. How is it different from the candy you started with? The three main types of rock (sedimentary, metamorphic, and igneous) are distinguished based on how they’re formed. The entire process by which rocks are formed is called the rock cycle, and like a circle, it has no beginning or end. In this rock cycle project, we simulated the formation of sedimentary rocks by pressing the pieces of Starburst into a lump. We simulated the formation of metamorphic rocks by adding heat and pressure in steps 4 and 5. The final three steps of the project show how igneous rocks are formed. Since the rock cycle is continuous, do you think you could use your igneous “rock” from the final steps and start the whole project over? Give it a try! For more fun studying and experimenting with geology, check out these science projects:
The great Jingdezhen kilns that had supplied the most artistically advanced ceramics to the world for centuries were largely destroyed during the dislocations that led to the fall of the Ming Dynasty (1368 – 1644). Fortunately, the Manchu rulers of the new Qing (pronounced Ching) Dynasty (1644 - 1911) were enthusiastic patrons of the arts. The Imperial Porcelain factories were rebuilt under the Kangxi emperor and production resumed in 1683. The peak of Chinese ceramic production was seen in the reigns of Kangxi (1661-1722), Yongzheng (1722-1735), and Qianlong (1735-1796) during which improvement was seen in almost all ceramic types, including the blue and white wares, polychrome wares, etc. The improved enamel glazes of early Qing Dynasty being fired at a higher temperature also acquired a more brilliant look than those of the Ming Dynasty. During the Qing Dynasty, potters began using bright colors to adorn plates and vases with meticulously painted scenes. Porcelain ceramicists continued developing five-colored ware by applying a variety of underglaze pigments to floral, landscape, and figurative scenes - a style which was (and is) highly sought-after in the West. The development of fencai (粉彩) enamel was one of the most significant technical contributions made to ceramics during the Qing period. Since the colors appeared softer than those of five-colored wares, fencai is also known as soft color (軟彩). The new opaque colors enabled painters to blend tints to create a multitude of shades and hues. Fencai enamel was first introduced in the Kangxi period, and its production reached a mature stage in the Yongzheng era. As the improved fencai enamels had a wider range of colors and each could be applied in a variety of tones, they could be used to depict some of the highly complicated pictorial compositions of flower and plant forms, figures, and even insects. The Qing Dynasty is a period specially noted for the production of color glazes. In the area of monochromes, Qing potters succeeded in reproducing most of the famous glaze colors found in ceramic wares of the Song, Yuan and Ming Dynasties. In addition, they created a variety of new glazes, thus bringing vibrant energy to Chinese porcelain and art.
Reflecting a figure over the x-axis can be a little tricky, unless you have a plan. In this tutorial, see how to use the graph of a figure to perform the reflection. Check it out! A point is a fundamental building block of math. Without points, you couldn't make lines, planes, angles, or polygons. That also means that graphing would be impossible. Needless to say, learning about points is very important! That makes this tutorial a must see! When you look in the mirror, you see your reflection. In math, you can create mirror images of figures by reflecting them over a given line. This tutorial introduces you to reflections and shows you some examples of reflections. Take a look! Just about everything in math has a name! Did you know that the line you reflect a figure over has a special name? It's called the line of reflection! Watch this tutorial and learn about the line of reflection. To graph a function or plot an ordered pair, you need to use a coordinate plane, so you should learn all about it! In this tutorial, you'll learn about the x-axis and see where it's located in the coordinate plane. Want to see how to reflect a figure over the x-axis? Then this tutorial was made for you! In this tutorial, you'll see how to use coordinates from the original figure to reflect the figure over the x-axis. Take a look!
Earthwatch scientist Dr. Mika Peck studies the impact of human activity on the rainforest of the Ecuadorian Andes, a biodiversity hotspot. Why the Ecuadorian Andes? An expedition to the Ecuadorian Andes in 1995 led Mika Peck to pursue a Ph.D. in tropical ecology at the University of Stirling (Australia), with fieldwork in Kakadu National Park in northern Australia. The impact of human activity on natural systems in tropical and temperate countries became the main thrust of his research. In 2005 he received funding for the Primenet project, which aims to conserve the critically endangered brown-headed spider monkey and other primates of northwestern Ecuador. Says Dr. Peck: “This is one of the most beautiful places in the world. It can only be reached by donkey, trekking for five hours. It is a fairytale setting - orchids, hummingbirds, big cats, tapirs, moths the size of dinner plates - and is one of the richest areas for bird species." A great moment in the field: Says Dr. Peck: “We took our work a stage further as capacity has been built to run and manage a research station in the western Andean slopes at the Santa Lucía Reserve. The station links communities to local and international scientists to address real issues facing people, habitat, and wildlife. It also plays a key role in sustainable development, providing income to the community-owned Santa Lucía Cloudforest Reserve and capacity-building for the next generation of Ecuadorian researchers.”
The gallbladder is a small, sac-like organ on the right side of the abdomen, just beneath the liver. The gallbladder stores bile, a digestive fluid produced by the liver. Gallbladder cancer is uncommon. When gallbladder cancer is discovered at its earliest stages, the possibility of curing it is very good. However, gallbladder cancer is difficult to diagnose because it often has no signs or symptoms. Unfortunately, most gallbladder cancers are discovered at a late stage, when the prognosis is often poor. Gallbladder cancer signs and symptoms may include: - Abdominal pain, particularly in the upper right portion of the abdomen - Abdominal bloating - Anorexia/loss of appetite - Weight loss (non-intentional) - Yellowing of the skin and whites of the eyes (jaundice) Factors that can increase the risk of gallbladder cancer include: - Gallbladder cancer is more common in women than men. - The risk of gallbladder cancer increases with age. - Gallbladder cancer is most common in people who've had gallstones in the past. Just because a person has a history of gallstones, however, does not mean he or she will develop cancer, as the incidence of gallbladder cancer is rare. - Other gallbladder conditions that can increase the risk of gallbladder cancer include: porcelain gallbladder, choledochal cyst, and chronic gallbladder infection. Determining the extent of gallbladder cancer Once a doctor diagnoses gallbladder cancer, he or she will determine the extent (stage) of the cancer. Understanding its stage helps determine your prognosis and treatment options. Tests and procedures used to stage gallbladder cancer include: - Imaging tests that can create pictures of the gallbladder, including ultrasound; or - computerized tomography (CT); or - magnetic resonance imaging (MRI). Your doctor may recommend surgery to look inside your abdomen for signs that gallbladder cancer has spread. During this procedure, called laparoscopy, the surgeon makes a small incision in the abdomen and inserts a tiny camera. The camera allows the surgeon to examine organs surrounding the gallbladder for signs that the cancer has spread to surrounding organs and tissues. Tests to examine the bile ducts Your doctor may recommend procedures to inject dye into the bile ducts. This is followed by an imaging test that records where the dye goes. These tests can show blockages in the bile ducts and may include: - endoscopic retrograde cholangiopancreatography; or - magnetic resonance cholangiography; or - percutaneous transhepatic cholangiography. Stages of gallbladder cancer Stage I: Cancer is confined to the inner layers of the gallbladder. Stage II: Cancer has grown to invade the outer layer of the gallbladder and may protrude into nearby organs, such as the liver, stomach, intestines, or pancreas. This stage of cancer may also include less extensive tumors that have spread to nearby lymph nodes. Stage III: Cancer has grown to invade more than one of the nearby organs, or it may invade the portal vein or hepatic artery. Stage IV: Cancer includes tumors of any size that have spread to distant areas of the body. Treatment options will depend on the stage of cancer, your overall health and preferences. The initial goal of treatment is to remove the gallbladder cancer, but when that isn't possible, other therapies may help control the spread of the disease and keep you as comfortable as possible. Surgery to remove the gallbladder Early gallbladder cancer that is confined to the gallbladder is most often treated with an operation to remove the gallbladder (cholecystectomy). Surgery to remove the gallbladder and a portion of the liver Gallbladder cancer that extends beyond the gallbladder and into the liver is sometimes treated with surgery to remove the gallbladder, as well as a portion of the liver and bile ducts that surround it. Whether additional treatments after a successful surgery will lessen the chance of the cancer returning is unclear. Some studies found that additional treatments lessen the chance, so your doctor may recommend chemotherapy, radiation therapy or a combination of both following surgery. Additional treatments are still controversial because so few studies have been done to evaluate the effectiveness of additional treatments. Treatments for late-stage gallbladder cancer Surgery can't cure gallbladder cancer that has spread beyond the gallbladder. Instead, doctors use treatments that may relieve signs and symptoms of cancer to make you as comfortable as possible. Options may include: - Chemotherapy, a drug treatment that uses chemicals to kill cancer cells - Radiation therapy, which uses high-powered beams of energy, such as X-rays, to kill cancer cells Procedures to relieve blocked bile ducts Advanced gallbladder cancer can cause blockages in the bile ducts, causing further complications. Procedures can relieve the blockage. For instance, surgeons can place a hollow metal tube (stent) in a duct to hold it open or surgically reroute bile ducts around the blockage (biliary bypass). National Cancer Institute, Mayo Clinic, Cancer Treatment Centers of America.
1 to 5 Our Living World is a series of books on Environmental Studies. It is based on the latest NCERT syllabus. The series also meets the objectives laid down in the National Curriculum Framework (NCF). The books will make children sensitive towards the environment and the need for its protection. - The books include sections on environmental issues to create awareness in children. In addition, there are tips on how to care for the environment. - The books reinforce learning through extensive exercises and test papers. - Activity pages after every unit make learning a hands-on and fun-filled experience. - The Time to Do section promotes learning through interactive activities.
Scientists have often wondered how woolly mammoths survived and thrived in the frigid climes of the far north in Earth’s last ice age. The hemoglobin in elephant (and human) blood cannot easily transfer oxygen to other cells in the body at low temperatures. Instead, the blood’s hemoglobin holds onto its oxygen in icy extremities and the tissue eventually dies; that’s the main reason we get frostbite. There must, then, have been something special about mammoth hemoglobin. A cooling climate, not human hunters, were at fault for the extinction of the prehistoric cave bear (Ursus spelaeus), according to a new study. Researchers examining cave bear remains now say the giant vegetarians died from starvation and much earlier than previously thought. “The disappearance of the cave bear around 27,500 years ago was probably due to the significant decline in quantity and quality of plant food, which in turn was the result of marked climatic cooling,” [Telegraph] said researcher Anthony J. Stuart. Previous radiocarbon dating of cave bear remains incorrectly placed their apocalypse at 14,000 years ago because some of the remains were actually those of brown bears, still alive today, that were mistakenly identified. The new study excludes previous errors and includes new data taken from remains found in ancient hibernation sites in the Alps. The new extinction date, 27,800 years ago, coincides with a period of significant climate change, known as the Last Glacial Maximum [or Ice Age], when a marked cooling in temperature resulted in a reduction or total loss of the vegetation that the cave bears ate (today’s brown bears are omnivores) [LiveScience.com].
Regardless of whether we believe them to be true, we all have extensive knowledge of cultural stereotypes. But how does this information become associated with certain groups in the first place? Research published in Psychological Science, a journal of the Association for Psychological Science, suggests that cultural stereotypes are the unintended but inevitable consequence of sharing social information. "We examined how social information evolves when it is repeatedly passed from person to person," explained psychological scientist Doug Martin, who leads the Person Perception Laboratory at the University of Aberdeen. "As it passes down a chain of individuals, social information that is initially random complex and very difficult to remember becomes a simple system of category stereotypes that can be learned easily." According to Martin and colleagues, stereotypes may have negative consequences when they contribute to prejudice, but they can also help us make sense of the world around us, helping us in "the way we organize, store, and use information about other people." "For example, if we meet a stranger, stereotypes provide us with a foundation on which we can begin to build an impression of this person and therefore guide our behaviour towards them," says Martin. Martin and colleagues conducted lab experiments in which they asked people to remember information about novel alien characters and then pass this information from person to person. Like the game "Telephone," they expected the information to change as it travelled down the chain of people. Volunteers were asked to learn personality attributes that described the aliens, all of whom shared certain physical features such as their color, their shape, or the way they moved. Each person was then tested to see what they could remember. Whatever information they produced was then passed on to be learned by the next volunteer and so on until a chain of information was created. "As information is passed from person to person, what begins as a chaotic and random association of aliens and attributes becomes simpler, more structured and easier to learn," says Martin. "By the end of the chain we have what look very much like stereotypes with physical features - such as color - strongly associated with the possession of specific personality attributes." The researchers say stereotypes appear to form and evolve because people share similar cognitive limitations and biases. People are more likely to confuse the identity of individuals when they belong to the same social category than when they belong to different categories. Similarly, people are more likely to mistakenly think that individuals who belong to the same social category also share the same attributes. Because we all experience the same category-based memory biases, when social information is repeatedly shared it is continually filtered as it passes from one mind to the next until eventually it becomes organised categorically and a stereotype has formed. The scientists say their research appears to explain why some stereotypes have a basis in reality while others have no obvious origin. "For example, the cultural stereotype of Scottish people includes attributes that are overrepresented among Scots, such as wearing kilts and having red hair, but also attributes that seemingly have no basis in reality, such as being miserly or dour," says Martin. "Where a genuine relationship exists between social categories and attributes, people are very good at detecting this, remembering it and then passing this information on. Equally, however, where there is no existing relationship between social categories and attributes, we see this association emerging spontaneously over time as the social information evolves," Martin explains. "If we can understand how cultural stereotypes form and naturally evolve then we might be able to positively influence their content in the future." Co-authors include Jacqui Hutchison, Gillian Slessor, and James Urquhart of the University of Aberdeen; Sheila J. Cunningham of Abertay University; and Kenny Smith of the University of Edinburgh. The study was funded by a grant from the Economic and Social Research Council (ESRC). For ad rates, call Mike McCurdy at 877-634-9180 or email at [email protected] We have over 7,000 journalists who are subscribers. Top of Page Us \| Job Listings \| Help \| Site Map \| About Us Advertising Information \| HND Press Release \| Submit Information \| Disclaimer
Earlier this year, a slightly horrifying factoid made its way around the internet: Penguins poop so much that piles of their poop can be seen from space. But take heart, people who don’t like thinking about mountains of bird guano: It turns out that today’s penguin dung heap could be tomorrow’s source of nutrition for beautiful, fuzzy moss. A team of Australian researchers were looking into the source of nutrients for these Antarctic plants, the BBC explains, and had narrowed it down to “nitrogen that’s gone through algae, krill and fish.” That food chain leads to seabirds — penguins — but the researchers were puzzled: Since no penguins live on the elevated lakeside site in East Antarctica, the researchers had to work out where the mysterious seabird poo came from. They realized that their moss beds were growing on the site of an ancient penguin colony. “Between 3,000 and 8,000 years ago, on the site where the moss is now growing, there used to be [Adelie] penguins,” said Prof Robinson. The moss growing on the penguin poop creates a tiny Antarctic jungle of lush green, which creates a habitat for insects and other tiny animals that can deal with cold. There is, however, a lot of this moss, which means that at one point there was a LOT of penguin poop lying around. Like, tons. Try not to think about that; maybe just focus on how nice and green it looks now. Get Grist in your inbox
How Businesses Use Regression Analysis Statistics Part of the Business Statistics For Dummies Cheat Sheet Regression analysis is a statistical tool used for the investigation of relationships between variables. Usually, the investigator seeks to ascertain the causal effect of one variable upon another — the effect of a price increase upon demand, for example, or the effect of changes in the money supply upon the inflation rate. Regression analysis is used to estimate the strength and the direction of the relationship between two linearly related variables: X and Y. X is the "independent" variable and Y is the "dependent" variable. The two basic types of regression analysis are: Simple regression analysis: Used to estimate the relationship between a dependent variable and a single independent variable; for example, the relationship between crop yields and rainfall. Multiple regression analysis: Used to estimate the relationship between a dependent variable and two or more independent variables; for example, the relationship between the salaries of employees and their experience and education. Multiple regression analysis introduces several additional complexities but may produce more realistic results than simple regression analysis. Regression analysis is based on several strong assumptions about the variables that are being estimated. Several key tests are used to ensure that the results are valid, including hypothesis tests. These tests are used to ensure that the regression results are not simply due to random chance but indicate an actual relationship between two or more variables. An estimated regression equation may be used for a wide variety of business applications, such as: Measuring the impact on a corporation's profits of an increase in profits Understanding how sensitive a corporation's sales are to changes in advertising expenditures Seeing how a stock price is affected by changes in interest rates Regression analysis may also be used for forecasting purposes; for example, a regression equation may be used to forecast the future demand for a company's products. Due to the extreme complexity of regression analysis, it is often implemented through the use of specialized calculators or spreadsheet programs.
Leading up to our task... Students had daily experiences that intentionally provided information that helped with the design of the structure. - On Monday, students observed and compared a cup of water in the sun vs. a cup of water covered with saran wrap in the sun. How does the Sun impact the cups? - On Tuesday, students compared how the Sun impacts a variety of the Earth's surfaces (rocks, soil, water, ice and sand). Which surface was warmer or cooler? Why? (K-PS3-1). - Students blocked the Sun's rays by creating shadows. (This proved to really be valuable when students positioned their structures outside.) (K-PS3-1),(K-PS3-2) I can identify an observable pattern when something comes between the Earth's surface and the sun. - Students "toured" a variety of Earth's surfaces with Google Earth. What did you notice? - Students compared the impact of the Sun with light/dark/shiny surfaces. What absorbs or reflects the sun's energy? - Students identified real objects they knew that help reduce the sun's light from shining. (umbrella, roof, sunglasses, tent) - Read many books on the Sun. Here are a few that we explored. On Thursday, students were presented with the following task: People get hot sitting in the sun for long periods of time. Your team has been hired to engineer a structure that will reduce the warming effect of sunlight on an area. Students got into teams of 2-3. They had to brainstorm ideas that they thought would be best to reduce the warming effect of the sun on a cup of ice that would be under their structure. (I loved it when I overheard a student say, "We have to get a piece of dark felt" before even seeing the materials. Loved hearing the planning, thought, and reasoning.) Then, the groups were presented with a variety of materials. Some that are shown below. Light/dark fabric, craft sticks, saran wrap, foil, tape, blocks, etc.. Let the building begin... When the group below first had their structure out, several people kept asking them to turn their structure so that the "arch" was how you see here. But at the beginning they had the arch away from the sun. Once the sun (finally) came out and the group could see the shadow, they turned the structure so that the "arch" created a shadow to protect the cup. At first, when the group chose the saran wrap, I thought it was an odd choice to have it exposed and not covered. The group remembered from an earlier lesson that the water cup that was covered retained more water than the cup without saran wrap. They were thinking! So apparently, I timed it better last year when I first did this lesson. When we went out to check our structures, you could clearly see which structure reduced the warming effects on the cup of ice. But with the high temps and humidity on Friday, we were too late! The ice had melted in all cases. Unfortunately, the rain was moving in otherwise we would have replaced the ice and tried it again for less time. Even without a "clear winner" the vocabulary, application and process was one of our best science discoveries of the year! Constructing explanations and designing solutions in K–2 builds on prior experiences and progresses to the use of evidence and ideas in constructing evidence-based accounts of natural phenomena and designing solutions. •Use tools and materials provided to design and build a device that solves a specific problem or a solution to a specific problem. (K-PS3- 2) Many other cross cutting concepts were integrated as well!
A "Great Cause for Better Citizens"? Attitudes Towards the New Deal In this activity students read letters from ordinary people to government leaders in the Roosevelt Administration. Then they interpret the range of attitudes about the changing role of the federal government during the New Deal. The letters for this activity all contain reading supports and teachers can differentiate this activity for different levels of learners by choosing which letters to use in the activity. Students will analyze letters from the 1930s to identify the impact of the New Deal on the lives of ordinary people. Students will interpret people's attitudes towards the New Deal and changes it caused in the role of the federal government. Step 1: The teacher should choose at least two letters for students to read. The teacher may alter the activity by giving students letters that express a range of opinions or letters that directly contrast with each other. The teacher may also choose to give different sets of letters to different groups of students. The teacher can differentiate the lesson for different levels of students by selecting which letters to give to students. Step 2: (Optional opening discussion) Ask students to describe the reasons why someone might write to the president or another elected official. Do they think people write to criticize, to praise, or both? Do students think the letters matter to elected officials? Do they think it matters when ordinary people write to officials? Conclude the discussion by telling students that during the New Deal, millions of ordinary people wrote to President Roosevelt and members of his administration to tell him their hopes and concerns about the New Deal. These letters are a remarkable window into the lives of ordinary people and their views on the changing role of the government during the New Deal. Step 3: Tell students that they will be working in groups (or pairs) to analyze letters that ordinary people wrote to the government about their views on the New Deal. Divide students into pairs or small groups. Give each group a set of 2 to 6 letters and a graphic organizer. Students should work in their groups to read the letters and complete the graphic organizer. Step 4: Either in writing or discussion, students should answer the question on the graphic organizer based on their readings of the letters: The New Deal was a turning point in the role of the federal government in the everyday lives of ordinary people. The relief programs of the New Deal altered the social contract, giving the federal government a much greater hand in providing for the basic needs of its citizens. Consequently New Deal programs provided, for the first time, direct relief in the form of payments, food, household supplies, and jobs. The New Deal also entailed a great deal of protections for consumers (especially in the security of bank deposits) and workers. The majority of Americans were extremely grateful for the changes in the federal government; some even demanded more radical changes. However, some feared that the New Deal would make people too dependent on the government; others called it socialism outright. No matter what their views, however, Americans wrote to President Roosevelt and other members of his government to tell him how they felt. During his presidency the White House (alone!) received around 8,000 letters a day, compared with about 800 a day during the Hoover Administration. Roosevelt worked hard to cultivate a personal bond between himself and the voters through his Fireside Chats. During these radio broadcasts, which were announced with great fanfare and drew millions of listeners, Roosevelt explained in everyday language the goals and workings of his various New Deal programs. The president encouraged his listeners to write to him and their other elected officials to tell what they thought of the programs. In this way he built a strong constituency for his agenda. \| American Social History Project/Center for Media Learning, 2009Creator \| American Social History Project/Center for Media Learning Copyright American Social History Project/Center for Media and Learning. This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 Unported License. \| Teaching ActivityCite This document \| American Social History Project/Center for Media Learning, “A "Great Cause for Better Citizens"? Attitudes Towards the New Deal,” HERB: Resources for Teachers, accessed March 11, 2014, http://herb.ashp.cuny.edu/items/show/1483.
Techniques for active listening \|Mirroring\|\|This means to repeat back phrases or words that the speaker uses. This shows the speaker that you have listened and it gives them a sense of recognition.\| \|Paraphrasing\|\|This means to rephrase or restate what you have heard in your own words to ensure that you have understood the content of the message. It gives the speaker an opportunity to elaborate on or clarify what he/she is saying and might stimulate greater objectivity by the speaker.\| \|Summarising\|\|Summarising involves pulling together the main elements of the discussion and organising them so that they can be reviewed, confirmed or corrected.\| Listening Practice Training ExerciseYou can use this exercise with a group of students or student representatives to help them think about the value of closed and open questions. Split the group into pairs, A & B. A’s are listeners, B’s are speakers. Take B’s out of the room and explain to them that they are to talk about something they’re really interested in for 3 minutes. Separately, inform the A’s that whilst they are listening to their partner, every time B says something that makes them want to join in the conversation or ask a question, they put their hand up for five seconds then put it back down. Ask them to do this for the entire conversation. A’s are not allowed to interact with B’s other than to look at them. At the end of the three minutes, ask the B’s how they felt whilst talking to A, emotions evoked, etc. Ask the A’s what it felt like not to get actively involved in the conversation. Questioning practice training exerciseYou can use this exercise with a group of students or student representatives to help them think about the value of closed and open questions. You will need: - Copies of two different pictures or photos. The people that are sketching should draw what they think is in Drawing 1 as closely as they can based on the answers to the closed questions asked. Get everyone to compare their images with each other and the source drawing and follow with a discussion. Swap the roles of the pairs and this time the person drawing can only ask open questions. Get everyone to compare their images with each other and the source drawing and follow with a discussion. Tips for facilitatorsHere are some essential points to bear in mind when you facilitate discussions. \|Stay on time\|\|The time you will have for the session will not be as long as you would like and you will have a lot of things to fit in. You will need to involve the other panel members in the questioning and ensure that everyone gets the chance to speak. Remember to use closed questioning to draw questioning to an end.\| \|Stay neutral\|\|A s a member of the review team it is important to stay neutral but it is particularly important for facilitators to ensure that they are not perceived as being biased.\| \|Focus\|\|It will help if you stick to the agenda. Use your questioning skills to bring people back to the point if they go astray and do not be afraid of (politely) reminding them of the original question.\| \|Stimulate and encourage responses\|\|It is your responsibility as a facilitator to ensure that everyone feels comfortable to participate. This is especially important when talking to the student group, as some students might not feel comfortable to speak in front of a group. Do your best to make sure that the environment is conducive to students feeling comfortable talking. Your listening and questioning skills will be valuable here.\| \|Regulate\|\|Try to avoid letting the same people speak all the time, you need to get an input as broad as possible. As facilitator you are responsible for managing the discussion and should ensure everyone that wants to contribute can do so.\| Tips for an effective communication - Keep good eye contact during conversations. - Be aware of your body language. Try to keep it open to show that you are interested. - Avoid negative mannerisms. - Be attentive. Try nodding, smiling or making small agreeing noises. - Keep an open mind to what you are hearing. - Do not interrupt to impose your solutions on the speaker. - Clarify your understanding with the speaker. - Pay attention to the response and let the person completely finish what they have to say. - Pay attention to non-verbal cues, e.g. signs of discomfort or tension. - Speak slowly and clearly and be consistent. - Take notes and clarify any points that have not been understood.
Element 1: Foundations and Current Status of American Indian Education Purpose: To ensure educators working with American Indian students are aware of past efforts at improving the academic achievement of these students, the limited success of these efforts, and current federally funded Indian education programs - Understand past efforts to assimilate Indians through English-only assimilationist schooling and the opposition Indians may show to efforts at forced assimilation. - Know the lasting effects of the Indian New Deal of the 1930s on American Indian education. - Understand the effects of the Indian Self-Determination and Civil Rights movements on American Indian education. - Understand the relationship between Indian tribes, states, and the federal government's Bureau of Indian Education. Activity 1: Understand the History of American Indian Education Activity 2: Understand the Current Status of American Indian Education Element 2: American Indian CulturesPurpose: Educators will understand the great cultural diversity among American Indians, as well as some of their commonalities. Educators will understand: - What makes someone an American Indian, and what is a tribe today? - What is an extended family? - What is the significance of traditional American Indian values, such as humility, interconnectedness, and reciprocity? - What should all Americans know about American Indians? Activity 1: Be Aware of Tribal and Family Structures Activity 2: Understand American Indian Traditional Tribal Values Task 4: Summarize Snapshot Findings Summarizing the data collection tasks accomplished under Activity 1 will give a measurement of a school's performance as it relates to the school's native students. Educators should focus on: - assessing native student academic achievement results with that of other student populations within the school; - assessing how the curriculum and instructional content and methods support the academic needs of the native students; - assessing the professional development needs of the staff regarding American Indian education; and - identifying the school staff's awareness level about the local American Indian tribe(s). Analyzing Program Needs and Setting Goals This tool is useful for recording the results of data collection with the goal of identifying the school's strengths and needs, and proposing the core goals. It is suggested that a different analysis sheet be completed for each focus area studied. Alternate format: PDF Buried Treasure: Developing a Management Guide From Mountains of School Data This document, Buried Treasure: Developing a Management Guide From Mountains of School Data, uses a story form to illustrate the use of a set of key indicators as a management guide for a fictional school board and superintendent. The story is provided as an illustrative example of using school data. The story is the result of work on how to structure and organize a group of key performance indicators as a management guide for local educators. It was developed by The Center on Reinventing Public Education at the University of Washington's Daniel J. Evans School of Public Affairs under a grant from the Wallace Foundation. Element 3: Understanding Your School and CommunityPurpose: Assessing American Indian students' academic performance and working with local tribes and other Indian organizations are necessary to develop culturally responsive teaching methods. Educators should: - Examine current American Indian student test scores, attendance rates, and dropout rates; - Work with tribes and community organizations; and - Work with national American Indian organizations and the National Indian Education Association. Activity 1: Take a Snapshot of Your School and Community Activity 2: Work With and Involve Community and Parents Element 4: Use Culturally Responsive Teaching MethodologiesPurpose: Some research suggests one reason for the achievement gap faced by American Indian students is cultural conflicts between American Indian homes and schools. Accordingly, culturally responsive teaching methodologies should address: - American Indian learning styles; - Indianizing curriculum; - Ethnomathematics and ethnoscience; - American Indian charter and magnet schools; and - Language revitalization. Activity 1: Helping American Indian Children to Learn Activity 2: Integrate American Indian History and Culture into School Curriculum Activity 3: The Role of American Indian Charter and Magnet Schools Activity 4: Teaching Indigenous Languages
Planting new trees can help to reduce the amount of CO2 in the air. Gases like carbon dioxide and methane are major contributors to the changing climates. Reforestation is an effective mitigation strategy to fight global warming. In addition to benefiting the climate, reforestation helps protect important species of animals. Reforestation helps to rebuild habitats and degradation which are the leading threats to the health of a species. Deforestation damages soil and habitats through erosion. Reforestation can help to restore what the erosion has damaged. In addition, regional watersheds that have been damaged by deforestation can be brought back to health through reforestation. Regional watersheds are an important resource for human development. Reforestation can also help humans to address world hunger issues and deal with water usage and availability. Restoring forests has many benefits on the chemical, social and biological levels of an entire ecosystem. Reforestation can also help to supply jobs for those who lack skills to be employed in other industries. Therefore, it benefits not only the environment, but the economy as well.Learn more about Environmental Science
Group Activity Cards Use groups of 3. Materials: String, scissors, metersticks \| Bring the String Find the lengths of five large objects in the classroom using string. Cut off the string to indicate each length. In a corner of the classroom, two group members hold the string against the two adjoining walls so that there is no slack. (See the figure below.) The other group member measures the distance in meters between the corner and the point at which each of the other two group members is holding one end of the string. Use the Pythagorean Theorem to find the length in meters of the object whose string measurement you found. Repeat the procedure for the other objects.
Discoveries and the creation of new knowledge are the building blocks of what is known in the sciences. Thousands of students and researchers from around the world participate in scientific research, experiments, and publishing within many fields. Countless innovations and new developments are the results of these efforts. This tutorial will introduce the processes used to distribute this information, introduce common sources of science information, and then describe how scientists find information to inform and support their research. After completing the Guide to Science Information Resources, students will be able to do the following:
2. (Science: ornithology) Any species of Psittacus, Chrysotis, Pionus, and other genera of the family Psittacidae, as distinguished from the parrakeets, macaws, and lories. They have a short rounded or even tail, and often a naked space on the cheeks. The gray parrot, or jako (P. Erithacus) of Africa (see Jako), and the species of amazon, or green, parrots (Chrysotis) of America, are examples. Many species, as cage birds, readily learn to imitate sounds, and to repeat words and phrases. (Science: marine biology) Parrot weed, any fish of the genus scarus. One species (S. Cretensis), found in the Mediterranean, is esteemed by epicures, and was highly prized by the ancient greeks and romans. Origin: Prob. Fr. F. Pierrot, dim. Of Pierre Peter. F. Pierrot is also the name of the sparrow. Cf. Paroquet, Petrel, Petrify.
Schoolies, Aged 6-10 years Generally, a healthy child will follow their own individual growth curve, which corresponds to their age and height and weight. It is important to remember that each child is different and not to compare your child with their friends’ growth and development. The World Health Organization has growth charts, which you can find below. In general terms you can expect to see these key milestones when your child is between 6 and 10 years old - Children aged 6-10 years usually grow in spurts, averaging about 3 kg and 6 cm each year1. - At 6 years old, your child’s social development will become stronger as they hold friendship in high regard. They reach an important stage of their cognitive development as they learn to read and write2. - At age 7, your child might be able to write stories and read longer books. Around this age, children begin to develop strong likes and dislikes2. - At 8 years old your child will be more self-sufficient that ever. They should be able to understand the meaning of right and wrong2. - At 9 years old a child is likely to be interested in activities that require fine motor and muscle skills, including sports, music and crafts. They should be able to work well as a team or in group projects2. - Around 10 years peer acceptance can become important. Your child might be able to think in a more abstract way2. - The final growth spurt will begin at the start of puberty, which can happen anytime between 9-15 years of age3. If you have any concerns please discuss these with your healthcare professional. WedMD, 2013: http://children.webmd.com/tc/growth-and-development-ages-6-to-10-years-what-to-expect Accessed 7th April 2017. British Council, 2013: https://learning-development.britishcouncil.org/pluginfile.php/34207/course/section/4478/SD_6-12_stages_of_development.pdf Accessed 22nd March 2017 Medline Plus, 2013: http://www.nlm.nih.gov/medlineplus/ency/article/002456.htm Accessed 7th April 2017.
Definition of current: Current is defined as the flow of charge per unit time. that is I = q/t There is flow of energy due to current called electrical energy. This energy can be converted into another forms and whenever there is conversion of electrical energy into another form of energy occurs then this conversion or transformation is called effect of electic current. The following are the major effects of electric current: - Heating effects of electric current - Magnetic effect of electric current - Chemical effect of electric current Let us discuss these effects one by one. Today we will discuss the heating effect of current: When electric current flows through a resistor, it gets heated. This converion of electrical energy into heat energy results in the heating effects of current. Following are the major reasons for this: - Duation for which current passed - Nature of the substance through which current passed. Applications of heating effects of curent: All electrical heating instruments like electrical fuse, bulb, water heaters, electric heaters are the applications of heating effects of current.
Ebola is a viral hemorrhagic (bleeding) illness that has a high fatality rate. The virus was discovered in 1976 near the Ebola River in the present-day Democratic Republic of Congo. There are five strains of the Ebola virus -- Tai Forest, Sudan, Bundibugyo, Zaire, and Reston. Four of the strains (Reston is the exception) are responsible for outbreaks in humans. The Ebola virus is harbored by fruit bats, gorillas, monkeys, forest antelope, chimpanzees, and porcupines. Humans can contract the virus by coming into close contact with the body or bodily fluids (including blood) of an infected animal. Once the virus spreads to a human, person-to-person transmission is possible. Since 1976, outbreaks have occurred sporadically in Zaire, Sudan, Democratic Republic of Congo, Gabon, and Uganda. The largest outbreak by far began in March 2014 and lasted into April 2016. It affected Guinea, Liberia, Sierra Leone, Senegal, and Nigeria. This West Africa Ebola outbreak resulted in 28,652 reported cases and 11,325 deaths. Visit the Centers for Disease Control (CDC) website for the latest outbreak statistics. In between human outbreaks, Ebola is believed to be harbored in animals that act as a “reservoir” for the virus. When a human contracts Ebola by handling an infected animal, person-to-person transmission can then lead to an outbreak. Ebola can be transmitted directly or indirectly. Direct transmission refers to the virus passing from an infected person to another person via sexual contact or by infected body fluids (blood, tears, feces, urine, vomit, for example) through contact with mucous membranes or broken skin. Indirect transmission refers to a person picking up a virus from a contaminated object, such as infected surgical equipment or a needle. The signs and symptoms of Ebola virus are divided into two stages. First comes the "dry" phase, which varies from person to person. It frequently includes fever greater than 101°F, intense weakness, severe headache, joint/muscle pain, and sore throat. It may also include vomiting, diarrhea, abdominal pain, rash, and internal bleeding. Some people with the illness go on to develop symptoms associated with the "wet" phase. These include bleeding from the eyes, nose, ears, and rectum. Lab tests may reveal abnormal liver and kidney function. Levels of white blood cells and platelets may be elevated. The incubation period of Ebola, defined as the period of time from exposure to the virus until the onset of symptoms, is 21 days. The average time from exposure to symptom development is about 8 – 10 days; bleeding is usually a later symptom that signifies severe infection. In lab conditions, the Ebola virus has been shown to spread through the air. However, in real-world living conditions and in hospital settings, there is no evidence that Ebola can be transmitted through the air. While there are fears that Ebola could mutate and become more easily transmissible, the director of the CDC, Dr. Tom Frieden, stated that there has been little change in the Ebola virus in the past 40 years. He also said that there is no evidence that Ebola has undergone any changes that would make it easier to spread from person to person. Every Ebola outbreak is different. Historically, the larger Ebola outbreaks have had a fatality rate of 25% to almost 90%. The Democratic Republic of the Congo Ministry of Health reports that the DRC outbreak has shown a 67% fatality rate from Aug. 2018 to Sept. 2019. There is no cure for Ebola. New therapies are being investigated. Treatment for Ebola consists of supportive care which often includes administering intravenous (IV) fluids and monitoring and maintaining appropriate electrolyte, oxygen, and blood pressure levels. Prevention and treatment of other infections that may develop in the Ebola-infected patient is important as well. More than two decades in the making, a vaccine for Ebola was approved in Europe in late 2019. While now approved in Europe, the Ebola vaccine known as Ervebo has been approved by the US FDA in December of 2019. Vaccines to stop the spread of Ebola have already been administered three times in Africa, according to the World Health Organization, starting in 2015 when more than 16,000 volunteers were vaccinated. They were used again in May-July 2016 in Equateur Province, and again in the eastern region of Kivu in the Democratic Republic of the Congo in 2018-19. Another investigational vaccine is expected to be used in 2019 for the DRC outbreak. This vaccine requires a second booster 56 days after the first dose, and is designed to work against the Zaire ebolavirus type. Although none have been approved by the FDA yet, four Ebola treatments have been attempted during the 2018 DRC outbreak on an investigational basis. These are ZMapp, REGN-EB3, mAb114, and remdesivir. The trial of two of the experimental drugs was halted early when the other two showed greater survival rates in Ebola patients. REGN-EB3 and mAb114 therapy made survival rates “much higher” according to the CDC. Although their investigational trials ended early, both ZMapp, an antibody cocktail experimental therapy for Ebola, and remdesivir have been proven effective in the laboratory in summer 2019. These drug therapies were successful in 2014 during the West Africa Ebola outbreak. The ZMapp therapy consists of three monoclonal antibodies that are designed to treat existing Ebola infection. Monoclonal antibodies work by binding to proteins in the virus and “targeting” them for destruction by the immune system. Research continues into these therapeutic approaches. Some drugs may be more effective in outbreaks with different strains of Ebola. These are difficult drugs to develop because Ebola virus is an RNA virus, and as such it is always mutating, according to the CDC. Ebola virus infection has never taken place in the United States, according to the CDC. The only people with Ebola infection in the US acquired the disease elsewhere or got the infection from someone who entered the country already infected like two US caregivers. People in areas known to have cases of Ebola can take the following precautions to minimize the risk of contracting the virus. Meticulous hygiene is necessary. Avoid people and bodily fluids of those known or suspected of having Ebola. Do not have contact with bats and wild animals; do not consume raw or undercooked animals that may have the virus. Only highly specialized, trained professionals with adequate protective gear should administer medical care to Ebola patients and handle the dead bodies of Ebola victims. Should you need medical care while you are in an area known to harbor Ebola, contact your embassy or consulate for a referral for an appropriate facility. IMAGES PROVIDED BY: - iStock / MedicineNet - Centers for Disease Control and Prevention (CDC) / MedicineNet - Getty Images - Centers for Disease Control and Prevention (CDC) / WHO / MedicineNet - Getty Images - Getty Images - Centers for Disease Control and Prevention: "2014 Ebola Outbreak in West Africa," "CDC lab research shows two treatments effective against DRC Ebola strain," "CDC Telebriefing on the Update on Ebola Outbreak in West Africa," "Ebola Hemorrhagic Fever Information Packet," "Ebola in Democratic Republic of the Congo—Transcript," "Outbreaks Chronology: Ebola Hemorrhagic Fever," "Prevention," "Questions and Answers on Ebola," "Questions and Answers on Experimental Treatments and Vaccines for Ebola," "Signs and Symptoms," "Treatment," "Virus Ecology Graphic." - Chimerix, INC - Global Health Policy: "The Current Ebola Outbreak and the U.S. Role: An Explainer." - World Health Organization: "Disease Outbreaks," "Ebola Response Roadmap Situation Report, 8 October 2014," "Ebola Virus Disease," "Ebola virus disease distribution map: Cases of Ebola virus disease in Africa since 1976," "Frequently asked questions on Ebola virus disease," "WHO prequalifies Ebola vaccine, paving the way for its use in high-risk countries."
It's easy to think of climate change as a distant and not-too-terrible threat. Tell that to the 700-some residents of Virginia's culturally unique Tangier Islands, which lie smack in the middle of Chesapeake Bay: New research shows that sea level rises due to climate change has already consumed two-thirds of the islands' land since 1850, and much of the rest will be gone in 50 years unless something's done to slow the sea's advance. The study's authors do not mince words: "The U.S. Army Corps of Engineers recognizes that climate change is upon us and that adaptation to climate change is 'not optional,'" write Army Corp of Engineers researchers David Schulte, Karin Dridge, and Mark Hudgins in Scientific Reports. "The Tangier Islands and the Town [of Tangier] are running out of time, and if no action is taken, the citizens of Tangier may become among the first climate change refugees in the continental U.S.A." To come to that conclusion, Schulte, Dridge, and Hudgins collected maps of the Tangier Islands going back to 1850. Using specialized software developed by the United States Geological Survey, the researchers determined that, in 1850, the three islands—Goose, Uppards, and Tangier (home to the Town of Tangier)—comprised about 875 hectares, or about 3.4 square miles. By 2013, the last year maps of the islands were updated, a combination of rising seas and eroding shores had cut that number to just 319 hectares, or 1.2 square miles. If those trends continue, "Uppards is expected to be inundated at an accelerating rate compared to the semi-protected Tangier, while Goose, the smallest of the Tangier Islands, is predicted to be entirely inundated by 2038," the team writes. Tidal creeks will then begin to permeate Uppards and Tangier, eroding the land and breaking Tangier into three parts. Even under conservative scenarios, both islands should be submerged by around 2100, with more extreme scenarios "predicting these islands will be lost by the late 2060s." It may be possible to save that land with a mix of breakwater systems, sand dredging, and tree planting. "If no action is taken," the researchers write, "significant wildlife habitat will be lost, as well as the culturally unique Town of Tangier, the last offshore fishing community in Virginia waters of Chesapeake Bay"—and perhaps the first American victims of climate change. "Catastrophic Consequences of Climate Change" is Pacific Standard's year-long investigation into the devastating effects of climate change—and how scholars, legislators, and citizen-activists can help stave off its most dire consequences.
I have noticed that students often get confused between AREA and PERIMETER. They also make mistakes in writing the correct unit. The activity described here helped clear these two concepts for my students. This activity also helps students understand why we need a standard unit to measure and what the standard unit for area is. Divide the class into groups of 4 to 5 students. Instruct each group to fill the inside of a tile on the floor or the table top using different objects – notebooks, newspaper, crayons or bottle caps. After they finish ask each group how many (number) objects they used to fill up the inside of the tile or table top. Each group will give you different answers like 20 notebooks or 10 newspapers or 100 bottle caps, etc. Have a class discussion. Ask your students why despite the size of the tile/table top being the same, each group had a different answer. Here you can discuss the need for a standard unit. After this activity and class discussion, students themselves will conclude that Unit blocks can be used to measure the AREA and the unit of area is square unit. Here you can ask them why it makes sense to use square units. Allow them to think and give answers. You may get different answers. After listening to their views, tell them that any standard must easily be “constructed” on the spot and it is not convenient to transport a standard from place to place. From this point of view a square is the easiest figure to specify as it has just the one dimension, its side! The square can also fill (tessellated) up any area without leaving any gaps! You can also incorporate another activity to show them the difference between area and perimeter. - Make several square cards (say the size of a chessboard square). Take the side as 1 unit and area as 1 square unit. - Suppose you give the students 12 cards and ask them to make rectangles of different sizes. You can make a 2 X 6, a 3 X 4 or a 1 X 12 rectangle. - Ask students – what property all these rectangles have in common (area!) - Ask them to find the perimeter of each of these figures. They will have different perimeters. Find the one with the least perimeter and the one with the most. - This shows that same areas can have different perimeters. - Have classroom discussion:- If you think of these shapes as the surfaces of dining tables then o The number of plates and dishes you can place on the table will depend on the area. o The number of people who can sit around the table will depend on the perimeter! - Ask the students to use a thread of a given length and create different figures which will have the same perimeter but different areas. What time is it? Being able to tell the time is an important skill that children learn in primary school. This activity described not only helps children learn to tell the time but also to convert the 12 hour format into a 24 hour one. Start your class by asking the students why a clock displays numbers only from 1 to 12. Allow your students to brainstorm. Ask them to come up with common proverbs related to time, such as “Time and tide wait for none,” or “A stitch in time saves nine” to get them thinking about the subject. The following activity enables students to read and write time in different ways. This activity can be done inside or outside the classroom. Ask 12 students to sit in a circle (like a clock) holding placards. Each card will have three numbers on it. Right on top will be time in the 24 hour format followed by time in the 12 hour format and finally time in minutes at the bottom. - Place a shoebox (or any empty box) with time chits inside. - The chits should have time written in all possible ways. 11:55, 5 minutes to 12, 55 minutes past 11, 5 minutes past 2, 2:05, half past 6, 18:30, etc. - Children take turns, walk to the centre of the circle, pick up a chit from the box, read out the time and show it on the clock (that their classmates have formed) using their hands or two sticks. These kind of activities also highlight the role of language in mathematics. 11.55 is eleven fifty five or fifty five minutes past eleven or five minutes to twelve. This is an opportunity for the teacher to talk about what the day means to the common man and to a scientist/mathematician. For the common man a day is 12 hours (the other 12 being night). So we have am and pm. For the scientist/mathematician a day is 24 hours (it is a cycle). There is no am or pm. The starting point is 12 midnight. Learning to read time in the traditional way is important even in this digital age for it improves a child’s motor and cognitive skills besides his mathematical skills. Understanding time the traditional way is also necessary to later understand concepts like time zones and international time. The author is a mathematics teacher and primary coordinator in Atul Vidyalaya, Atul, Gujarat. She can be reached at [email protected].
What is the Act about? The Juvenile Justice Act is a branch of criminal law that applies to people who are too young to be held accountable for their actions. Since children are seen as the most valuable asset, there is a pressing need to address juvenile justice. The Juvenile Justice (Care and Protection of Children) Act 2015 was passed by the Indian Parliament amid heated debate, lengthy hearings, and street demonstrations by child rights organizations and some members of Parliament. The primary goal of this act is to address numerous concerns relating to child care, probation, social reintegration, and children in legal dispute. History of the Act: Juveniles were given special care under the Criminal Procedure Act of 1898. According to the Act, offenders under the age of twenty-one were eligible for probation if they behaved well. After which the Indian Jail Committee drafted the Indian Children Act which gave the specific regional government have the authority to enforce independent juvenile laws in their jurisdictions. Subsequently the provinces of Madras, Bengal, and Bombay each passed their own Acts, these laws included provisions for the establishment of a specialized juvenile justice system. The most significant change brought under this subject was with the introduction of The Juvenile Justice (Care and Protection of Children) Act, 2000. Anyone under the age of 18 was deemed a child under this act, and they were never permitted to stand trial as an adult. “Nirbhaya Delhi Gang Rape Case,” an incident that occurred on December 16, 2012 questioned the purpose and the objective of this very law. The after effect of this incident posed concerns about the applicability of law in the field of juvenile justice since one of the accused was 6 months under the age of 18. The presence of an individual under the age of 18 in such a heinous crime as rape forced the Indian legislature to pass a new law. This resulted in the introduction of the Juvenile Justice (Care and Protection of Children) Act, 2015. Critical Analysis of the Act: The definitions used are dealt under Section 2 of the Act. Section 2 (12) defines a “child” as means a person who has not completed eighteen years of age and Section 2 (13) states that a “child in conflict with law” means a child who is alleged or found to have committed an offence and who has not completed eighteen years of age on the date of commission of such offence. As per the Juvenile Justice Act of 2000, a person was considered juvenile if he/she was below 18 years of age. Following the amendment, it was determined that, depending on the nature of the offence, an individual between the ages of 16 and 18 may be tried as an adult. This amendment established a distinction between a child and a juvenile, meaning that someone convicted of a crime and between the ages of 16 and 18 is a juvenile, not a child. The case is heard by the juvenile justice board if the aspect of heinous crime is lacking. The objective behind this is so that the accused’s age does not obscure the essence of the cruelty he committed on the victim and to ensure that children who come into conflict with the law are treated differently than adults, depending on the circumstances of the case. It is necessary to ensure that Act isn’t in conflict with other laws. Section 15 of the Act provides that if a child has completed or is over the age of sixteen and is accused of committing a heinous crime, the Board shall perform a preliminary examination of his mental and physical capacity to commit the crime, ability to recognize the ramifications of the crime, and the circumstances under which he allegedly committed the crime. If this isn’t ensured then it would amount to violation of Section 84 of the Indian Penal Code, 1860. Section 53 reflects upon rehabilitation and reintegration services in institutions registered under this Act and management of the same, which aims are proving basic facilities to these children and also aiming at their skill development, through like skill education and by improving themselves as an individual with the help of occasional therapy by counselling according to the need of the juvenile. This is considered to be beneficial to the child when he leaves for the real world. Sections 74 to 89 of the Act provides provisions to protect the children from offences against them. Any person who reveals a child’s name, address, or school, or any other information that could lead to identification of the child in violation of the law, a child victim or witness of a crime, shall be punished by imprisonment for up to six months or a fine of up to two lakh rupees, or both. Whoever has actual charge or power over a child and assaults, abandons, beats, reveals, or wilfully neglects the child, or causes or procures the child to be assaulted, abandoned, harmed, revealed, or neglected in a manner likely to cause the child undue mental or physical distress, shall be punished by imprisonment for a period up to three years. Any person who employs a child for begging or exploits a child employee shall be punished with imprisonment for a period of five with and/or a fine of one lakh rupees. Whoever gives intoxicating liquor or narcotic drug or psychotropic substance to a child shall be punishable with imprisonment for seven years and/or fine which many extend up to one lakh rupees. Anyone who sells or buys a child for any reason is subject to rigorous imprisonment which may extend to five years and a fine of one lakh rupees. However, this is contrary to Section 370 of the Indian Penal Code, according to which, anyone who commits the offence of human trafficking shall be punishable with rigorous punishment for a term not less than seven years and which may extend to ten years or even to imprisonment for life it the accused in involved in trafficking of more than one individual. These provisions aim at protecting the children of the country, however, it is the duty of the legislatures to ensure that the provisions are in contrary to any other laws. The Act also takes the child’s welfare into consideration by under Section 92 regarding the placement of a child suffering from disease requiring prolonged medical treatment in an approved place. The Act also authorizes a Juvenile Justice Board, comprised of psychologists and sociologists, to determine whether or not a juvenile delinquent aged 16 to 18 can be charged as an adult. A new provision on fair trial has been introduced, in which the review would include the child’s special needs as part of the tenet of a fair trial in a child-friendly setting and Act establishes foster care. The police force’s special juvenile unit will also receive proper instruction which would help in avoiding kind of issues regarding the same. Challenges faced by the Juvenile System in India: There are many Challenges faced by the Juvenile System in India such as the lack of adequate funding to carry out programmers to meet the needs of children’s treatment and safety. As a result, children who are subject to Juvenile Justice Board are not reintegrated into society on time, affecting their mental health and changing their attitudes. Lack of standards in government-run Child Care Institutions (CCIs) such as Special Homes, Shelter Homes, Day Care Centers and Children Homes run by government and non-governmental organizations. There is a lack of understanding among police officers about procedure to be followed. Section 107 of the Act speaks about establishing of Special Juvenile Police Units in each district and city, headed by a police officer and two social workers having experience of working in the field of child welfare, of whom one shall be a woman. These officers are required to undergo training to enable to them to provide protection of the children. However, there is glitch implementation of the same. Since there is a need to secure to the interest of the child, there should be no compromise with respect to the qualifications of these officers. In most cases, children who have been juveniles are more receptive to improvement. The failures in the criminal justice system can be traced back to a lack of education, a lack of social services, and an inability to incarcerate the most violent criminals. Aside from ensuring public safety, the primary priorities of the criminal justice system should be skill enhancement, rehabilitative, recovery, meeting medical needs, and effective reintegration of juveniles into the community. The Juvenile Justice Act should be aggressively implemented. Thus, the government must ensure that the act is duly carried out by the authorities. Ensuring and improving the efficiency of the juvenile protective care process will offer justice to juvenile offenders who have come in conflict with the law. VIT School of Law
A: Coronaviruses are a large family of viruses ranging from the common cold to much more serious diseases and can infect both humans and animals, according to the World Health Organization (WHO). The 2019 Novel Coronavirus is a new coronavirus strain that healthcare professionals are still learning about. For the most up-to-date information, we recommend visiting the Centers for Disease Control and Prevention. According to the Centers for Disease Control and Prevention (CDC), patients with confirmed COVID-19 infections have reportedly had mild to severe respiratory illness with symptoms of: Symptoms of COVID-19 may appear in as few as 2 days or as long as 14 days after exposure. This is based on what has been seen previously as the incubation period of MERS viruses. According to the CDC, the virus is thought to spread mainly from person-to-person: COVID-19 can sometimes be spread by airborne transmission meaning some infections can be spread by exposure to the virus in small droplets and particles that linger in the air for minutes to hours. These viruses may be able to infect people who are farther than 6 feet away or after an infected person has left the space under certain conditions. There is evidence of these transmissions within enclosed spaces that had inadequate ventilation. Available data indicates it is much more common for COVID-19 to spread through close contact with an infected person than through airborne transmission. Respiratory droplets can also land on surfaces and objects. It may be possible that a person can get COVID-19 by touching a surface or object that has the virus on it and then touching their own mouth, nose, or possibly their eyes. However, this is not thought to be a common way the virus spreads. For more information, refer to the CDC website. What you need to know to help keep your family safe at home. Get our full list of EPA-approved products that can be used against COVID-19. Follow these easy steps using the bleach you have at home. Bleach and other disinfectants are not suitable for consumption or injection under any circumstances. People should always read the label for proper usage instructions. Disinfecting surfaces with bleach and other disinfecting products is one of the ways to help stop the spread of COVID-19, according to the Centers for Disease Control. Our products are safe when used as directed. It’s critical that everyone understands the facts in order to keep themselves safe and healthy.
Gulf Stream map from 1943 The term "current" describes the motion of something. Ocean.currents describe the movement of water from one location to another in the sea. Currents are vital for: 1) moving nutrients and food sources in the sea; 2) cooling, heating and providing water to terrestrial areas, and 3) transferring heat from the Equator to the Poles. Currents are generally measured in meters per second or in knots (1 knot = 1.85 kilometers per hour or 1.15 miles per hour). Currents affect the Earth's climate by driving warm water from the Equator and cold water from the poles around the Earth. The warm Gulf Stream, for instance, brings milder winter weather to Bergen, Norway, than to New York, much further south. Ocean currents are driven mainly by prevailing winds and differences in water density, which changes with temperature and salinity of the seawater. The overall pattern of ocean circulation appears to driven by thermohaline circulation (“thermo” for heat and “haline” for salinity”) — a conveyor belt driven by the sinking of dense cold water in North Atlantic. This draws warm surface water (the Gulf Stream) from the south and sets in motion currents that affect all the world’s oceans. Currents can also be influenced by salt and and influxed of fresh water. Salt water is heavier than fresh water, As fresh water enters the systems it rides over ocean water and pulls some of the salt water into it, creating a sort of vacuum that draws in more deep ocean water. Saline water that flows from warm areas to cold areas loses heat and becomes more saline as water evaporates. The coldness and high salinity makes the water more dense. It sinks into the oceans. As it does surface water moves in to displace it. Websites and Resources: National Oceanic and Atmospheric Administration (NOAA) noaa.gov; “Introduction to Physical Oceanography” by Robert Stewart , Texas A&M University, 2008 uv.es/hegigui/Kasper ; Woods Hole Oceanographic Institute whoi.edu ; Cousteau Society cousteau.org ; Monterey Bay Aquarium montereybayaquarium.org Important Terms for Ocean Currents and Circulation According to the “Introduction to Physical Oceanography”: 1) General Circulation is the permanent, time-averaged circulation. 2) Abyssal also called the Deep Circulation is the circulation of mass, in the meridional plane, in the deep ocean, driven by mixing. 3) Wind-Driven Circulation is the circulation in the upper kilometer of the ocean forced by the wind. The circulation can be caused by local winds or by winds in other regions. 4) Gyres are wind-driven cyclonic or anticyclonic currents with dimensions nearly that of ocean basins. [Source: Robert Stewart, “Introduction to Physical Oceanography”, Texas A&M University, 2008] 5) Boundary Currents are currents flowing parallel to coasts. Two types of boundary currents are important: A) Western boundary currents on the western edge of the ocean tend to be fast, narrow jets such as the Gulf Stream and Kuroshio Current off Japan; B) • Eastern boundary currents are weak, e.g. the California Current. 6) Squirts or Jets are long narrow currents, with dimensions of a few hundred kilometers, that are nearly perpendicular to west coasts. 7) Mesoscale Eddies are turbulent or spinning flows on scales of a few hundred kilometers. In addition to flow due to currents, there are many types of oscillatory flows due to waves. Normally, when we think of waves in the ocean, we visualize waves breaking on the beach or the surface waves influencing ships at sea. But many other types of waves occur in the ocean. A) Planetary Waves depend on the rotation of the earth for a restoring force, and they including Rossby, Kelvin, Equatorial, and Yanai waves. B) Surface Waves sometimes called gravity waves, are the waves that eventually break on the beach. The restoring force is due to the large density contrast between air and water at the sea surface. C) Internal Waves are sub-sea wave similar in some respects to surface waves. The restoring force is due to change in density with depth. D) Tsunamis are surface waves with periods near 15 minutes generated by earthquakes. E) Tidal Currents are horizontal currents and currents associated with internal waves driven by the tidal potential. F) Edge Waves are surface waves with periods of a few minutes confined to shallow regions near shore. The amplitude of the waves drops off exponentially with distance from shore. Forces Behind Ocean Currents Oceanic currents are driven by three main factors: 1) Winds drive currents that are at or near the ocean's surface. Near coastal areas winds tend to drive currents on a localized scale and can result in phenomena like coastal upwelling. On a more global scale, in the open ocean, winds drive currents that circulate water for thousands of miles throughout the ocean basins. [Source: NOAA] 2) Thermohaline circulation. This is a process driven by density differences in water due to temperature (thermo) and salinity (haline) variations in different parts of the ocean. Currents driven by thermohaline circulation occur at both deep and shallow ocean levels and move much slower than tidal or surface currents. 3) The rise and fall of the tides. Tides create a current in the oceans, which are strongest near the shore, and in bays and estuaries along the coast. These are called "tidal currents." Tidal currents change in a very regular pattern and can be predicted for future dates. In some locations, strong tidal currents can travel at speeds of eight knots or more. Prevailing winds both push water and create circulation by displacing water at the surface that allows upwelling — the upward flow of cold water from deep in the ocean to the surface of the sea. The cold oxygen-poor water is often rich in nutrients such as nitrates, phosphate and silicate that are consumed by creatures on the bottom of the food chain beginning with phytoplankton that in turn feed marine life further up the food chain. Important Concepts in the Study of Ocean Currents According to the “Introduction to Physical Oceanography”: To begin our study of currents near the sea surface, let’s consider first the response of the ocean to an impulse that sets the water in motion. For example, the impulse can be a strong wind blowing for a few hours. The water then moves only under the influence of Coriolis force (force resulting from the earth's rotation that deflects movement to the right in the northern hemisphere and to the left in the southern hemisphere). Such motions are said to be inertial. The mass of water continues to move due to its inertia. If the water were in space, it would move in a straight line according to Newton’s second law. But on a rotating earth, the motion is much different. The following are some important things to consider when discussing currents. [Source: Robert Stewart, “Introduction to Physical Oceanography”, Texas A&M University, 2008] 1) Changes in wind stress produce transient oscillations in the ocean called inertial currents : A) Inertial currents are very common in the ocean. B) The period of the current is (2π)/f. 2) Because of the Coriolis Affect, movement can be 90 degrees to the right of the wind in the northern hemisphere and 90 degrees to the left of the wind in the southern hemisphere. 3) Steady winds produce a thin boundary layer, the Ekman layer, at the top of the ocean. Ekman boundary layers also exist at the bottom of the ocean and the atmosphere. The Ekman layer in the atmosphere above the sea surface is called the planetary boundary layer. 4) The Ekman layer at the sea surface has the following characteristics: A ) Direction: 45 degrees to the right of the wind looking downwind in the Northern Hemisphere. B) Surface Speed: 1–2.5 percent of wind speed depending on latitude. C) Depth: approximately 40–300 meters depending on latitude and wind velocity. 4) Careful measurements of currents near the sea surface show that: A) Inertial oscillations are the largest component of the current in the mixed layer. B) The flow is nearly independent of depth within the mixed layer for periods near the inertial period. Thus the mixed layer moves like a slab at the inertial period. C) An Ekman layer exists in the atmosphere just above the sea (and land) surface. Surface drifters tend to drift parallel to lines of constant atmospheric pressure at the sea surface. This is consistent with Ekman’s theory. E) The flow averaged over many inertial periods is almost exactly that calculated from Ekman’s theory. 5) Spatial variability of Ekman transport, due to spatial variability of winds over distances of hundreds of kilometers and days, leads to convergence and divergence of the transport such as producing upwelling far away from where the winds that generate them. 6) Ekman pumping, which is driven by spatial variability of winds, drives a vertical current, which drives the interior geostrophic circulation of the ocean. Tides and Currents Tides go up and down; currents move left and right. Tides create a current in the oceans, near the shore, and in bays and estuaries along the coast but currents in the open ocean are generally influenced more other factors. [Source: NOAA] Tides are driven by the gravitational force of the moon and sun. Tides are characterized by water moving up and down over a long period of time. Oceanic currents are driven by several factors. One is the rise and fall of the tides. Tides create a current in the oceans, near the shore, and in bays and estuaries along the coast. These are called "tidal currents." Tidal currents are the only type of currents that change in a very regular pattern and can be predicted for future dates. Currents are generally influenced more by winds and thermohaline circulation. Currents in coastal areas can be caused the ebb and flow of tides. In bays and straits where the water narrows the tides and currents can be quite strong. In some places such as the Bay of Fundy water levels can range 50 feet between low and high tide. In places where there are narrow straight currents can reach 15 knots when the tide ebbs and then lie still for 15 minutes or so and then start flowing with equal velocity in the other direction. Wind Driven Circulation You would think that currents on the surface of the ocean follow the prevailing winds. While this often true it isn’t always the case. Robert Stewart wrote in the “Introduction to Physical Oceanography”: Sometimes “strong currents, such as the North Equatorial Countercurrents in the Atlantic and Pacific Ocean go upwind. Spanish navigators in the 16th century noticed strong northward currents along the Florida coast that seemed to be unrelated to the wind. How can this happen? And, why are strong currents found offshore of east coasts but not offshore of west coasts? Answers to the questions can be found in a series of three remarkable papers published from 1947 to 1951. In the first, Harald Sverdrup (1947) showed that the circulation in the upper kilometer or so of the ocean is directly related to the curl of the wind stress if the Coriolis force varies with latitude. Henry Stommel (1948) showed that the circulation in oceanic gyres is asymmetric also because the Coriolis force varies with latitude. Finally, Walter Munk (1950) added eddy viscosity and calculated the circulation of the upper layers of the Pacific. Together the three oceanographers laid the foundations for a modern theory of ocean circulation. [Source: Robert Stewart, “Introduction to Physical Oceanography”, Texas A&M University, 2008] Sverdrup’s Theory of the Oceanic Circulation: While Sverdrup was analyzing observations of equatorial currents, he came upon the equation below relating the curl of the wind stress to mass transport within the upper ocean. To derive the relationship, Sverdrup assumed that the flow is stationary, that lateral friction and molecular viscosity are small, that non-linear terms such as u ∂u/∂x are small, and that turbulence near the sea surface can be described using a vertical eddy viscosity. He also assumed that the wind-driven circulation vanishes at some depth of no motion. Eddies and Whirlpools An eddy is a circular current of water. The ocean is a huge body of water that is constantly in motion. General patterns of ocean flow are called currents. Sometimes theses currents can pinch off sections and create circular currents of water called an eddy. NASA satellite images show eddies and small currents responsible for the swirling pattern of phytoplankton blooms. [Source: NOAA] You may have seen an eddy if you've ever gone canoeing and you see a small whirlpool of water while you paddle through the water. The swirling motion of eddies in the ocean cause nutrients that are normally found in colder, deeper waters to come to the surface. Significant eddies are assigned names similar to hurricanes. In the U.S., an oceanographic company called Horizon Marine assigns names to each eddy as they occur. The names follow chronologically along with the alphabet and are decided upon by staff at Horizon Marine. The staff try to think of creative ways to assign names. For example, an eddy that formed in the Gulf of Mexico in June 2010 is named Eddy Franklin after Ben Franklin, as he was known to have done research on the Gulf Stream. Old Sow is the name of the Western Hemisphere's largest whirlpool. While the turbulent water of Old Sow can be dangerous to small-craft mariners, its swirling motion has a positive environmental effect. It causes nutrients and tiny sea creatures normally found in the bay’s colder, deeper waters to rise to the surface. This process, called upwelling, ensures good eating for the resident fish and seabirds. When the tide comes in from the Bay of Fundy, located off the Atlantic Coast between the State of Maine and the Province of New Brunswick, a tremendous amount of ocean water, called a current, flows swiftly into a confined area called the Western Passage before emptying upriver into Passamaquoddy Bay. After making a sharp right turn to the north and traversing a deep trench, flowing past an underwater mountain, and encountering several countercurrents, a portion of the current "pinches off" to form the huge circular current called Old Sow, and, often, several smaller ones, nicknamed “piglets.” Circular currents of all sizes are commonly known as whirlpools, vortexes, eddies, and gyres. Old Sow varies in size but has been measured at more than 250 feet in diameter, about the length of a soccer field. While the turbulent water can be dangerous to small-craft mariners — some of whom have barely escaped a 12-foot drop into the Sow’s gaping maw — its swirling motion has a positive environmental effect. It causes nutrients and tiny sea creatures normally found in the bay’s colder, deeper waters to rise to the surface. This process, called upwelling, ensures good eating for the resident fish and seabirds. So why is the whirlpool called "Old Sow?" According to folklore, the name refers to the "grunting" noise — which sounds like hungry pigs slurping up their slop — made by the giant churning gyre. "Sow" may also be a mispronunciation of the word "sough" (pronounced suff), which means "sucking noise" or "drain." A turbidity current is a rapid, downhill flow of water caused by increased density due to high amounts of sediment. Turbidity currents can be caused by earthquakes, collapsing slopes, and other geological disturbances. Once set in motion, the turbid water rushes downward and can change the physical shape of the seafloor. [Source: NOAA] Turbidity is a measure of the level of particles such as sediment, plankton, or organic by-products, in a body of water. As the turbidity of water increases, it becomes denser and less clear due to a higher concentration of these light-blocking particles. Turbidity currents can be set into motion when mud and sand on the continental shelf are loosened by earthquakes, collapsing slopes, and other geological disturbances. The turbid water then rushes downward like an avalanche, picking up sediment and increasing in speed as it flows. Turbidity currents can change the physical shape of the seafloor by eroding large areas and creating underwater canyons. These currents also deposit huge amounts of sediment wherever they flow, usually in a gradient or fan pattern, with the largest particles at the bottom and the smallest ones on top. NOAA scientists use current meters attached with turbidity sensors to gather data near underwater volcanoes and other highly active geological sites. Also, satellite imagery is used to observe turbidity by measuring the amount of light that is reflected by a section of water. Geostrophic Currents and the Rubber Duckie Spill A geostrophic current is an oceanic current in which the pressure gradient force is balanced by the Coriolis effect. The direction of geostrophic flow is parallel to the isobars, with the high pressure to the right of the flow in the Northern Hemisphere, and the high pressure to the left in the Southern Hemisphere. [Source: Wikipedia] According to the “Introduction to Physical Oceanography”: Within the ocean’s interior away from the top and bottom Ekman layers, for horizontal distances exceeding a few tens of kilometers, and for times exceeding a few days, horizontal pressure gradients in the ocean almost exactly balance the Coriolis force resulting from horizontal currents. This balance is known as the geostrophic balance. The dominant forces acting in the vertical are the vertical pressure gradient and the weight of the water. The two balance within a few parts per million. [Source: Robert Stewart, “Introduction to Physical Oceanography”, Texas A&M University, 2008] Thus pressure at any point in the water column is due almost entirely to the weight of the water in the column above the point. The dominant forces in the horizontal are the pressure gradient and the Coriolis force. They balance within a few parts per thousand over large dist Barotropic and Baroclinic Flow: If the ocean were homogeneous with constant density, then constant-pressure surfaces would always be parallel to the sea surface, and the geostrophic velocity would be independent of depth. In this case the relative velocity is zero, and hydrographic data cannot be used to measure the geostrophic current. If density varies with depth, but not with horizontal distance, the constant-pressure surfaces are always parallel to the sea surface and the levels of constant density, the isopycnal surfaces. In this case, the relative flow is also zero. Both cases are examples of barotropic flow. Flow is primarily parallel to temperature fronts, and strong currents can exist along fronts even though the front may not move. It is therefore essential to track the motion of small eddies embedded in the flow near the front and not the position of the front. The Rubber Duckie Spill illustrates some of these concepts. On January 10, 1992 a 12.2-m container with 29,000 bathtub toys, including rubber ducks washed overboard from a container ship at 44.7 degrees N, 178.1 degrees E . Where these rubber duckies floated and where they ended up, sometimes months and years later, gave scientists good data on currents and circulation in the sea. Oceanic Transport of Heat and the Global Ocean Conveyor Belt According to the “Introduction to Physical Oceanography”: The ocean carry about half the heat out of the tropics needed to maintain earth’s temperature. Heat carried by the Gulf Stream and the north Atlantic drift keeps the far north Atlantic ice free, and it helps warm Europe. Norway, at 60 degrees N is far warmer than southern Greenland or northern Labrador at the same latitude. Palm trees grow on the west coast of Ireland, but not in Newfoundland which is further south.[Source: Robert Stewart, “Introduction to Physical Oceanography”, Texas A&M University, 2008] Wally Broecker (1987), working at Lamont-Doherty Geophysical Observatory of Columbia University, calls the oceanic component of the heat-transport system the Global Conveyor Belt. The basic idea is that surface currents carry heat to the far north Atlantic. There the surface water releases heat and water to the atmosphere, and it becomes sufficiently cold, salty, and dense that it sinks to the bottom in the Norwegian and Greenland Seas. It then flows southward in cold, bottom currents. Some of the water remains on the surface and returns to the south in cool surface currents such as the Labrador Current and Portugal Current. Richardson (2008) has written a very useful paper surveying our understanding of the global conveyor belt. The global ocean conveyor belt is a constantly moving system of deep-ocean circulation driven by temperature and salinity. The ocean is not a still body of water. There is constant motion in the ocean in the form of a global ocean conveyor belt. This motion is caused by a combination of thermohaline currents in the deep ocean and wind-driven currents on the surface. Cold, salty water is dense and sinks to the bottom of the ocean while warm water is less dense and remains on the surface. [Source: NOAA] The ocean conveyor gets its “start” in the Norwegian Sea, where warm water from the Gulf Stream heats the atmosphere in the cold northern latitudes. This loss of heat to the atmosphere makes the water cooler and denser, causing it to sink to the bottom of the ocean. As more warm water is transported north, the cooler water sinks and moves south to make room for the incoming warm water. This cold bottom water flows south of the equator all the way down to Antarctica. Eventually, the cold bottom waters returns to the surface through mixing and wind-driven upwelling, continuing the conveyor belt that encircles the globe. The deep bottom water from the north Atlantic is mixed upward in other regions and ocean, and eventually it makes its way back to the Gulf Stream and the North Atlantic. Thus most of the water that sinks in the north Atlantic must be replaced by water from the far south Atlantic. As this surface water moves northward across the equator and eventually into the Gulf Stream, it carries heat out of the south Atlantic. So much heat is pulled northward by the formation of north Atlantic bottom water in winter that heat transport in the Atlantic is entirely northward, even in the southern hemisphere. Much of the solar heat absorbed by the tropical Atlantic is shipped north to warm Europe and the northern hemisphere. A gyre is a large system of rotating ocean currents. There are five major gyres, which are large systems of rotating ocean currents. The ocean churns up various types of currents. Together, these larger and more permanent currents make up the systems of currents known as gyres. [Source: NOAA] Wind, tides, and differences in temperature and salinity drive ocean currents. The ocean churns up different types of currents, such as eddies, whirlpools, or deep ocean currents. Larger, sustained currents — the Gulf Stream, for example — go by proper names. Taken together, these larger and more permanent currents make up the systems of currents known as gyres. The five major gyres are: 1) the North Pacific Subtropical Gyre; 2) the South Pacific Subtropical Gyre; 3) the North Atlantic Subtropical Gyre, 4) the South Atlantic Subtropical Gyre, and 5) the Indian Ocean Subtropical Gyre. In some instances, the term “gyre” is used to refer to the collections of plastic waste and other debris found in higher concentrations in certain parts of the ocean. While this use of "gyre" is increasingly common, the term traditionally refers simply to large, rotating ocean currents. Winds blowing across the ocean surface push water away. Water then rises up from beneath the surface to replace the water that was pushed away. This process is known as “upwelling.” Upwelling occurs in the open ocean and along coastlines. The reverse process, called “downwelling,” also occurs when wind causes surface water to build up along a coastline and the surface water eventually sinks toward the bottom. Upwelling brings deep, cold, often nutrient-rich water to the surface that “wells up” from below. There are five major coastal currents affiliated with strong upwelling zones, the California Current, the Humboldt Current off Peru, the Canary Current, the Benguela Current off Namimbia, and the Somali Current. Robert Stewart wrote in the “Introduction to Physical Oceanography”: Because steady winds blowing on the sea surface produce an Ekman layer that transports water at right angles to the wind direction, any spatial variability of the wind, or winds blowing along some coasts, can lead to upwelling. [Source: Robert Stewart, “Introduction to Physical Oceanography”, Texas A&M University, 2008] Upwelling is important because: 1) it enhances biological productivity, which feeds fisheries; 2) cold upwelled water alters local weather. Weather onshore of regions of upwelling tend to have fog, low stratus clouds, a stable stratified atmosphere, little convection, and little rain. 3) Spatial variability of transports in the open ocean leads to upwelling and downwelling, which leads to redistribution of mass in the ocean, which leads to wind-driven geostrophic currents via Ekman pumping. Water that rises to the surface as a result of upwelling is typically colder and is rich in nutrients. These nutrients “fertilize” surface waters, meaning that these surface waters often have high biological productivity. Therefore, good fishing grounds typically are found where upwelling is common. To see how winds lead to coastal upwelling, consider north winds blowing parallel to the California Coast. The winds produce a mass transport away from the shore everywhere along the shore. The water pushed offshore can be replaced only by water from below the Ekman layer. This is upwelling. Because the upwelled water is cold, the upwelling leads to a region of cold water at the surface along the coast. Upwelled water is colder than water normally found on the surface, and it is richer in nutrients. The nutrients fertilize phytoplankton in the mixed layer, which are eaten by zooplankton, which are eaten by small fish, which are eaten by larger fish and so on. As a result, upwelling regions are productive waters supporting the world’s major fisheries. The important regions are offshore of Peru, California, Somalia, Morocco, and Namibia. Ekman transport and spatial variability of winds over distances of hundreds of kilometers and days leads to convergence and divergence of the transport and. A) Winds blowing toward the equator along west coasts of continents produces upwelling along the coast. This leads to cold, productive waters within about 100 kilometers of the shore. B) Upwelled water along west coasts of continents modifies the weather along the west coasts. To measure currents, you need three basic tools: 1) an observer, 2) a floating object or a drifter, and 3) a timing device. An observer stands on a ship, throws the drifter into the water, and then measures the time that it takes that object to move along the side of a ship. As technology improved over time, oceanographers began using mechanical current meters. A ship would deploy a meter and usually some sort of rotor would turn and measure the currents. This is still the basic process today; however there are more accurate and sophisticated instruments. [Source: NOAA] Currents are observed at depths throughout the water column and are measured over a period of time. Today in the open ocean, a drifter is similar to a buoy in the water that may be equipped with global positioning system technology or satellite communications that would relay data and information. Drifters can also submerge for long periods of time to measure ocean currents at a particular depth. The drifter would then resurface occasionally to send a signal with its data and position to observers on the land. In addition to buoys, there are other tools that are used to monitor currents. Acoustic Doppler Current Profiler (ADCP) is an instrument that measures the currents by emitting beams of sound, which reflect off of particles in the water and back to the ADCP. Commonly used to measure currents, it is normally deployed on the seafloor or attached to the bottom of a boat. It sends an acoustic signal into the water column and that sound bounces off particles in the water. The instrument can calculate the speed and direction of the current by knowing the frequency of the return signal, the distance it traveled, and the time it took for the signal to travel. Many oceanographers also use radio antennas and high frequency Radio Detecting and Ranging systems (radar) to measure surface ocean currents. Similar to the Acoustic Doppler Current Profiler, these shore-based instruments use the Doppler effect to determine when currents are moving toward or away from the shore or to measure the velocity of a current. At NOAA, oceanographers use knots to measure current speed. The term knot is defined as one nautical mile per hour. One nautical mile is equal to 1.85 kilometers. One knot is also 51.44 centimeters per second. After the ocean current measurements are collected, oceanographers download the data and then analyze it through a computer program. A statistical process called harmonic analysis determines the part of the current caused by the tides. This “tidal current” can then be predicted at that location for many years into the future. Other factors that influence the current, such as wind, cannot be forecast for more than a few days and are not included in the prediction. NOAA’s Center for Operational Oceanographic Products and Services (CO-OPS) is primarily responsible for predicting and measuring water levels and currents and disseminating this information. CO-OPS collects, analyzes, and distributes such data to maintain safe maritime navigation and waterborne commerce. Tide and current data is available from CO-OPS Products and Services website. Among the things that are offered are: 1) Sea Levels, a global map depicting regional trends in sea level, with arrows representing the direction and magnitude of change; 2) Real-Time Current Data, collected by NOAA current meters around the U.S.; 3) Historic Current Data.; 4) Tidal Current Predictions, predictions for more than 2700 tidal current stations nationwide; 5) Storm QuickLook, real-time oceanographic and meteorological observations at locations affected by a tropical cyclone. Why the Study of Currents Is Important Current data is critical for supporting safe and efficient shipping and marine transportation. With predicted, real-time, and forecasted currents, people can safely dock and undock ships, maneuver them in confined waterways, and safely navigate through coastal waters. This helps to avoid ship collisions or delay the arrival of goods. In addition, current measurements are important for search and rescue operations, environmental disasters, and coastal engineering projects. [Source: NOAA] When supporting search and rescue operations, understanding the speed and direction of the currents in an area helps to narrow down the rescue and recovery effort. Current prediction information can help scientists clean up after a hazardous oil spill by helping them understand the direction and movement of the oil. Engineers also use currents information to help build marine structures such as bridges or docks and piers. Current observations are also used to develop and evaluate coastal nowcast or forecast model products that are provided online. An Operational Forecast System provides a nowcast and forecast (up to 48 hours) of water levels, currents, salinity, water temperatures, and winds for a given area. These systems are located in coastal waters and the Great Lakes in critical ports, harbors, and estuaries. NOAA periodically conducts current surveys in areas around the nation to ensure the accuracy of tidal current predictions. Commercial and recreational mariners depend on this information for safe navigation. Image Sources: Wikimedia Commons; YouTube, NOAA Text Sources: National Oceanic and Atmospheric Administration (NOAA) noaa.gov; “Introduction to Physical Oceanography” by Robert Stewart , Texas A&M University, 2008 uv.es/hegigui/Kasper ; Wikipedia, National Geographic, Live Science, BBC, Smithsonian, New York Times, Washington Post, Los Angeles Times, The New Yorker, Reuters, Associated Press, Lonely Planet Guides and various books and other publications. Last Updated March 2023
You are here March 5, 2007 Compounds Show Promise Against Potential Bioterror Agent Botulism is a rare but serious illness that causes paralysis and can be fatal.It's caused by nerve toxins made by the bacterium Clostridium botulinum. "Type A" toxin is so deadly and easy to produce that the U.S. Centers for Disease Control and Prevention (CDC) considers it one of the highest-risk agents for bioterrorism. In a new study, researchers have identified two small molecules that could prove to be ideal countermeasures for a bioterror attack using botulinum toxin A. C. botulinum bacteria, which are commonly found in soil, can form spores that allow them to survive in a dormant state until they're exposed to conditions that support their growth. Infant botulism, the most common type of botulism, occurs when infants consume these spores, which then grow in their intestines and release toxin. In adults, most outbreaks are caused by contaminated home-canned foods. You can also get botulism through contaminated wounds. If diagnosed early, botulism can be treated with an antitoxin, which blocks the action of the toxin in the blood. But recovery still takes many months. The antitoxin can also cause serious side effects, has only a very short window of application and is expensive to produce in large enough quantities to combat a bioterrorism attack. Dr. Kim Janda of The Scripps Research Institute and his colleagues, with funding from NIH's National Institute of Allergy and Infectious Diseases (NIAID) and The Skaggs Institute for Chemical Biology, set out to find other compounds that could act against botulinum toxin A. The deadly toxin is known to attack a protein called SNAP-25 that is involved in nerve cell communication. The researchers therefore screened a "library" of about 66,000 small molecules to find ones that could disrupt the molecular interaction between the toxin and SNAP-25. Their study was published in the February 20, 2007, issue of the Proceedings of the National Academy of Sciences. The researchers found seven compounds they decided to test further in living animals. They also added an eighth compound the group had previously developed, called 2,4-dichlorocinnamic hydroxamic acid, that has a completely different mode of action. Mice were given botulinum toxin A along with injections of the potential inhibitors. Two of the compounds — 2,4-dichlorocinnamic hydroxamic acid and one of the small molecules, NA-A1B2C10 — modestly extended the animals' lives without noticeable side effects. Interestingly, NA-A1B2C10 had been the least effective of the final compounds at protecting SNAP-25 in the laboratory, demonstrating the importance of testing such compounds in living systems. These small molecules show promise against botulinum toxin A in animal models, but more studies are needed to demonstrate their efficacy. Both have relatively simple structures, so their biological activity might be readily optimized. The two compounds also have different modes of action, so they may be able to complement each other in a "cocktail" therapy. — by Harrison Wein, Ph.D.
The method uses the tri-state logic capabilities of microcontrollers in order to gain efficiency over traditional multiplexing. Although it is more efficient in its use of I/O, there are issues that cause it to be more complicated to design and render it impractical for larger displays. These issues include duty cycle, current requirements and the forward voltages of the LEDs. - 1 Origination - 2 Traditional multiplexing - 3 Problems with Charlieplexing - 4 Input data multiplexing - 5 GuGaplexing - 6 Chipiplexing - 7 Resources Charlieplexing was proposed in early 1995 by Charlie Allen at Maxim Integrated. The method, however, was known and utilized by various parties much earlier in the 1980s, and has been described in detail as early as in 1979 in a patent by Christopher W. Malinowski, Heinz Rinderle, and Martin Siegle of Department of Research and Development, AEG-Telefunken, Heilbronn, Germany for what they called a "three-state signaling system". Display multiplexing is very different from multiplexing used in data transmission, although it has the same basic principles. In display multiplexing, the data lines of the displays are connected in parallel to a common bus on the microcontroller. Then, the displays are turned on and addressed individually. This allows use of fewer I/O pins than it would normally take to drive the same number of displays directly. When using Charlieplexing, n drive pins can drive n digits with n − 1 segments. When simplified, it equates to n pins being able to drive n2 − n segments or LEDs. Traditional multiplexing takes many more pins to drive the same number of LEDs; 2n pins must be used to drive n2 LEDs (though a 1-of-n decoder chip can be used to reduce the number of microcontroller I/O pins to ). If the number of LEDs is known, then the previous equation can be worked backwards to determine the number of pins required. That is, L LEDs can be driven by pins. \|n\|\|n2 − n\| Charlieplexing in its simplest form works by using a diode matrix of complementary pairs of LEDs. The simplest possible Charlieplexed matrix would look like this: By applying a positive voltage to pin X1 and grounding pin X2, LED1 will light. Since current cannot flow through LEDs in reverse direction, LED2 will remain unlit. If the voltages on pin X1 and pin X2 are reversed, LED2 will light and LED1 will be unlit. The Charlieplexing technique does not actually make a larger matrix possible when only using two pins, because two LEDs can be driven by two pins without any matrix connections, and without even using tri-state mode. In this two-LED example, Charlieplexing would save one ground wire, which would be needed in a common 2-pin driver situation. However, the 2-pin circuit serves as a simple example to show the basic concepts before moving on to larger circuits where Charlieplexing actually shows an advantage. Expanding: tri-state logic If this circuit were to be expanded to accommodate 3 pins and 6 LEDs, it would look like this: This presents a problem, however. In order for this circuit to act like the previous one, one of the pins must be disconnected before applying charge to the remaining two. This can be solved by utilizing the tri-state logic properties of microcontroller pins. Microcontroller pins generally have three states: "high" (5 V), "low" (0 V) and "input". Input mode puts the pin into a high-impedance state, which, electrically speaking, "disconnects" that pin from the circuit, meaning little or no current will flow through it. This allows the circuit to see any number of pins connected at any time, simply by changing the state of the pin. In order to drive the six-LED matrix above, the two pins corresponding to the LED to be lit are connected to 5 V (I/O pin "high" = binary number 1) and 0 V (I/O pin "low" = binary 0), while the third pin is set in its input state. In doing so, current leakage out of the third pin is prevented, ensuring that the LED wished to be lit is the only one lit. Current will still flow across alternate paths (an alternate 2-LED path exists for every pair of pins in the 3-pin diagram, for example), but the reduced voltage drop across those LEDs in multi-LED paths will not be enough that they actually significantly[dubious ] illuminate. This effect is further reduced in the variant with individual resistors.[dubious ] The existence of alternative paths also means that up to two LEDs sharing either a common positive or negative path can be lit at the same time by connecting either power or ground to the third pin. At the same time, this will ensure that the other LED in the alternative path will not illuminate at all. By using tri-state logic, the matrix can theoretically be expanded to any size, as long as pins are available. For n pins, n(n − 1) LEDs can be in the matrix. Any LED can be lit by applying 5 V and 0 V to its corresponding pins and setting all of the other pins connected to the matrix to input mode. Under the same constraints as discussed above up to n − 1 LEDs sharing a common positive or negative path can be lit in parallel. Expanding: bigger and brighter The 3-wire circuit can be rearranged to this near-equivalent matrix (resistors have been relocated). This emphasizes the similarities between ordinary grid multiplex and Charlieplex, and demonstrates the pattern that leads to "the n-squared minus n" rule. In typical usage on a circuit board the resistors would be physically located at the top of the columns and connected to the input pin. The rows would then be connected directly to the input pin bypassing the resistor. The first setup is suitable only when identical LEDs are used, whereas in the second configuration with individual resistors, the resistors make it possible to mix different kinds of LEDs by providing each with its appropriate resistor. In these configurations, the relocated resistors make it possible to light multiple LEDs at the same time row-by-row, instead of requiring that they be lit individually. The row current capacity could be boosted by an NPN emitter follower instead of the typically much weaker I/O pin. Problems with Charlieplexing Because only a single set of LEDs, all having a common anode or cathode, can be lit simultaneously without turning on unintended LEDs, Charlieplexing requires frequent output changes, through a method known as flickering. When flickering is done, not all LEDs are lit quite simultaneously, but rather one set of LEDs is lit briefly, then another set, then another, and eventually the cycle repeats. If it is done fast enough, they will appear to all be on, all the time, to the human eye (persistence of vision). In order for a display to not have any noticeable flicker, the refresh rate for each LED must be greater than 50 Hz. Suppose 8 tri-state pins are used to control 56 LEDs through Charlieplexing, which is enough for 8 7-segment displays (without decimal points). Typically 7-segment displays are made to have a common cathode, sometimes a common anode, but without loss of generality suppose it is a common cathode. All LEDs in all 8 7-segment displays cannot be turned on simultaneously in any desired combination using Charlieplexing. It is impossible to get 56 bits of information directly from 8 trits (the term for a base-3 character, as the pins are 3-state) of information, as 8 trits fundamentally comprises 8 log23, or about 12.7 bits of information, which falls far short of the 56 bits required to turn all 56 LEDs on or off in any arbitrary combination. Instead, the human eye must be fooled by use of a flicker. Only one 7-segment display, one set of 7 LEDs can be active at any time. The way this would be done is for the 8 common cathodes of the 8 displays to each get assigned to its own unique pin among the 8 I/O ports. At any time, one and only one of the 8 controlling I/O pins will be actively low, and thus only the 7-segment display with its common cathode connected to that actively low pin can have any of its LEDs on. That is the active 7-segment display. The anodes of the 7 LED segments within the active 7-segment display can then be turned on in any combination by having the other 7 I/O ports either high or in high-impedance mode, in any combination. They are connected to the remaining 7 pins, but through resistors (the common cathode connection is connected to the pin itself, not through a resistor, because otherwise the current through each individual segment would depend on the number of total segments turned on, as they would all have to share a single resistor). But to show a desired number using all 8 digits, only one 7-segment display can be shown at a time, so all 8 must be cycled through separately, and in a 50th of a second for the entire period of 8. Thus the display must be refreshed at 400 Hz for the period-8 cycle through all 8 segments to make the LEDs flash no slower than 50 times per second. This requires constant interruption of whatever additional processing the controller performs, 400 times per second. Due to the decreased duty cycle, the current requirement of a Charlieplexed display increases much faster than it would with a traditionally multiplexed display. As the display gets larger, the average current flowing through the LED must be (roughly) constant in order for it to maintain constant brightness, thus requiring the peak current to increase proportionally. This causes a number of issues that limit the practical size of a Charlieplexed display. - LEDs often have a maximum peak current rating as well as an average current rating. - If the microcontroller code crashes, and a one-led-at-a-time Charlieplex is being used, the single LED left lit is under much higher stress than it would be in a row-at-a-time charliplexed display or in a traditionally multiplexed display, increasing the risk of a failure before the fault is spotted. Requirement for tristate All the outputs used to drive a Charlieplexed display must be tristate. If the current is low enough to drive the displays directly by the I/O pins of the microcontroller, this is not a problem, but if external tristates must be used, then each tristate will generally require two output lines to control, eliminating most of the advantage of a Charlieplexed display. Since the current from microcontroller pins is typically limited to 20 mA or so, this severely restricts the practical size of a Charlieplexed display. However, it can be done by enabling one segment at a time. Charlieplex matrixes are significantly more complicated, both in the required PCB layout and microcontroller programming, than are traditional multiplex matrices. This increases design time. Soldering components can also be more time-consuming than for multiplexed LED arrays. A balance between complexity and pin use can be achieved by Charlieplexing several pre-built multiplexed LED arrays together. When using LEDs with different forward voltages, such as when using different color LEDs, some LEDs can light when not desired. In the diagram above it can be seen that if LED 6 has a 4 V forward voltage, and LEDs 1 and 3 have forward voltages of 2 V or less, they will light when LED 6 is intended to, as their current path is shorter. This issue can easily be avoided by comparing forward voltages of the LEDs used in the matrix and checking for compatibility issues. Or, more simply, using LEDs that all have the same forward voltage. If a single LED fails, by becoming either open-circuit, short-circuit, or leaky (developing a parasitic parallel resistance, which allows current in both directions), the impact will be catastrophic for the display as a whole. Furthermore, the actual problematic LED may be very difficult to identify, because potentially a large set of LEDs which should not be lit may all come on together, and—without detailed knowledge of the circuit—the relation between which LED is bad and what set of LEDs all come on together cannot be easily established. If the failed LED becomes an open circuit, the voltage between the LED's 2 electrodes may build up until it finds a path through two other LEDs. There are as many such paths as there are pins used to control the array minus 2; if the LED with anode at node m and cathode at node n fails in this way, it may be that every single pair of LEDs in which one's anode is node m, cathode is p for any value of p (with the exceptions that p cannot be m or n, so there are as many possible choices for p as the number of pins controlling the array minus 2), along with the LED whose anode is p and cathode is n, will all light up. If there are 8 I/O pins controlling the array, this means that there will be 6 parasitic paths through pairs of 2 LEDs, and 12 LEDs may be unintentionally lit, but fortunately this will only happen when the one bad LED is supposed to come on, which may be a small fraction of the time and will exhibit no deleterious symptoms when the problem LED is not supposed to be lit. If the problem is a short between nodes x and y, then every time any LED U with either x or y as its anode or cathode and some node z as its other electrode is supposed to come on (without loss of generality, suppose U's cathode is connected to x), the LED V with cathode y and anode z will light as well, so any time EITHER node x or y is activated as an anode OR a cathode, two LEDs will come on instead of one. In this case, it lights only one additional LED unintentionally, but it does it far more frequently; not merely when the failed LED is supposed to come on, but when any LED that has a pin in common with the failed LED is supposed to come on. The problematic elements become especially difficult to identify if there are two or more LEDs at fault. What this means is that unlike most methods in which the loss of a single LED merely causes a single burned-out segment, when Charlieplexing is used, one or two burned-out LEDs, whatever the mode of failure, will almost certainly cause a catastrophic cascade of unintended lightings of the LEDs that still work, very likely rendering the entire device completely and immediately unusable. This must be taken into account when considering the required lifetime and failure characteristics of the device being designed. Input data multiplexing Charlieplexing can also be used to multiplex digital input signals into a microcontroller. The same diode circuits are used, except a switch is placed in series with each diode. To read whether a switch is open or closed, the microcontroller configures one pin as an input with an internal pull-up resistor. The other pin is configured as an output and set to the low logic level. If the input pin reads low, then the switch is closed, and if the input pin reads high, then the switch is open. One potential application for this is to read a standard (4×3) 12-key numeric keypad using only 4 I/O lines. The traditional row-column scan method requires 4 + 3 = 7 I/O lines. Thus Charlieplexing saves 3 I/O lines; however it adds the expense of 12 diodes, (since the diodes are only free when LEDs are used). A variation of the circuit with only 4 diodes is possible, however that method qualifies as lossy compression, because when certain combinations of buttons are pressed simultaneously, those signals interfere with the microcontroller's ability to read certain other buttons. The microcontroller can always detect when the data is corrupt, but there is no guarantee it can sense the original key presses, unless only one button is pressed at a time. (However, it is probably possible to arrange the circuit so that if at most any two adjacent buttons are pressed, then no data loss will occur.) Basically though, the input is only lossless in the 4-diode circuit if only one button is pressed at a time, or if certain problematic multiple key presses are avoided. In the 12-diode circuit, this is not an issue, and there is always a one-to-one correspondence between button presses and input data. However, there are so many diodes that are required to use the method (especially for larger arrays) that there is generally no cost savings over the traditional row-column scan method, unless for some reason the cost of a diode is only a fraction of the cost of an I/O pin, where that fraction is one over the number of I/O lines. \|This section is empty. You can help by adding to it. (March 2015)\| \|This section is empty. You can help by adding to it. (March 2015)\| - 'Almost no Part Clock' using Charlieplexed 7-segment LED displays. - Michael E Rule. Charlieplexing with LED dot matrix modules. Accessed March 20, 2013. Alternate Mirror - Maxim's appnote on Charlieplexing use in their chips. - This Instructables article explains both the theory and how to implement the design. - Don Lancaster's Tech Musings #152 is where the name Charlieplexing originated. - electronicdesign.com, Electronic Design Magazine, 1 page article on Charlieplexing for input data
Castleman disease is a rare disorder that involves an overgrowth of cells in your body's lymph nodes. The most common form of the disorder affects a single lymph node (unicentric Castleman disease), usually in the chest or abdomen. Multicentric Castleman disease affects multiple lymph nodes throughout the body and has been associated with human herpes virus type 8 (HHV-8) and human immunodeficiency virus (HIV). Treatment and outlook vary, depending on the variety of Castleman disease you have. The type that affects only one lymph node can usually be successfully treated with surgery. Many people with unicentric Castleman disease don't notice any signs or symptoms. The enlarged lymph node may be detected during a physical exam or an imaging test for some unrelated problem. Some people with unicentric Castleman disease might experience signs and symptoms more common to multicentric Castleman disease, which may include: - Unintended weight loss - Night sweats - Enlarged liver or spleen The enlarged lymph nodes associated with multicentric Castleman disease are most commonly located in the neck, collarbone, underarm and groin areas. When to see a doctor If you notice an enlarged lymph node on the side of your neck or in your underarm, collarbone or groin area, talk to your doctor. Also call your doctor if you experience a persistent feeling of fullness in your chest or abdomen, fever, fatigue, or unexplained weight loss. It's not clear what causes Castleman disease. However, infection by a virus called human herpesvirus 8 (HHV-8) is associated with multicentric Castleman disease. The HHV-8 virus has also been linked to the development of Kaposi's sarcoma, a cancerous tumor that can be a complication of HIV/AIDS. Studies have found that HHV-8 is present in nearly all HIV-positive people who have Castleman disease, and in about half of HIV-negative people with Castleman disease. Castleman disease can affect people of any age. But the average age of people diagnosed with unicentric Castleman disease is 35. Most people with the multicentric form are in their 50s and 60s. The multicentric form is also slightly more common in men than in women. The risk of developing multicentric Castleman disease is higher in people who are infected with a virus called human herpesvirus 8 (HHV-8). People with unicentric Castleman disease usually do well once the affected lymph node is removed. Multicentric Castleman disease may lead to life-threatening infections or organ failure. People who also have HIV/AIDS generally have the worst outcomes. Having either variety of Castleman disease may increase your risk of lymphoma. After a thorough physical exam, your doctor may recommend: - Blood and urine tests, to help rule out other infections or diseases. These tests can also reveal anemia and abnormalities in blood proteins that are sometimes characteristic of Castleman disease. - Imaging tests, to detect enlarged lymph nodes, liver or spleen. A CT scan or MRI of your neck, chest, abdomen and pelvis may be used. Positron emission tomography (PET) scans also may be used to diagnose Castleman disease and to assess whether a treatment is effective. - Lymph node biopsy, to differentiate Castleman disease from other types of lymphatic tissue disorders, such as lymphoma. A tissue sample from an enlarged lymph node is removed and examined in the laboratory. Treatment depends on the type of Castleman disease you have. Unicentric Castleman disease Unicentric Castleman disease can be cured by surgically removing the diseased lymph node. If the lymph node is in your chest or abdomen — which is often the case — major surgery may be required. If surgical removal isn't possible, medication may be used to shrink the lymph node. Radiation therapy also may be an effective way to destroy the affected tissue. You'll need follow-up exams, including imaging, to check for relapse. Multicentric Castleman disease Treatment for multicentric Castleman disease generally involves medications and other therapies to control cell overgrowth. Specific treatment depends on the extent of your disease and on whether you have HIV or HHV-8 infection or both. Treatment options for multicentric Castleman disease may include: - Immunotherapy. The use of drugs such as siltuximab (Sylvant) or rituximab (Rituxan) can block the action of a protein that is produced in excess in people who have multicentric Castleman disease. - Chemotherapy. This type of medication can slow the overgrowth of lymphatic cells. Your doctor may recommend adding chemotherapy if the disease doesn't respond to immunotherapy or if you have organ failure. - Corticosteroids. Drugs such as prednisone can help control inflammation. - Antiviral drugs. These drugs can block the activity of HHV-8 or HIV if you have one or both of those viruses. Preparing for an appointment You may be referred to a doctor who specializes in treating blood disorders (hematologist). What you can do - Write down the symptoms you have been experiencing and for how long. - Write down key medical information, including other conditions. - Make a list of all medications, vitamins and supplements that you're taking. Questions to ask your doctor - What's the most likely cause of my signs and symptoms? - What kinds of tests do I need? Do they require any special preparation? - What treatment do you recommend? Do I need surgery? In addition to the questions that you've prepared to ask your doctor, don't hesitate to ask other questions during your appointment. What to expect from your doctor Your doctor is likely to ask you a number of questions. Being ready to answer them may make time to go over points you want to spend more time on. You may be asked: - Do you have any other health conditions, such as HIV/AIDS or Kaposi's sarcoma? - When did you first begin experiencing symptoms? - Have your symptoms been continuous or occasional? - How severe are your symptoms? - Does anything seem to improve your symptoms? - What, if anything, appears to worsen your symptoms? Last Updated Aug 1, 2020
Why does a compass needle get deflected when brought near a bar magnet?SOLUTION: Compass needle gets deflected due to attractive or repulsive interactions between its magnetic field and the magnetic field of the bar magnet.Q 2. Draw magnetic field lines around a bar magnet.SOLUTION: List the properties of magnetic lines of force.SOLUTION: Some characteristic properties of the magnetic field lines are listed below: (A) Magnetic field lines start at the north pole and end at the south pole. (B) Magnetic field lines do not intersect each other, because there can’t be two directions of the magnetic field at any one point. (C) The degree of closeness of the field lines depends upon the strength of the magnetic field. Stronger the field, closer are the field lines.Q 4. Why don’t two magnetic lines of force intersect each other?SOLUTION: The direction of magnetic field (B) at any point is obtained by drawing a tangent to the magnetic field line at the point. In case, two magnetic field line intersect each other at the point P as shown in figure, magnetic field at P will have two directions, shown by two arrows, one drawn to each magnetic field line at P, which is not possible. Consider a circular loop of wire lying in the plane of the table. Let the current pass through the loop clockwise. Apply the right-hand rule to find out the direction of the magnetic field inside and outside the loop.SOLUTION: The magnetic field inside and outside the current-carrying loop is shown in the figure given below. The magnetic field in a given region is uniform. Draw a diagram to represent it.SOLUTION: The field lines inside the solenoid are in the form of parallel straight lines. This indicates that the magnetic field inside the solenoid is uniform. This is shown in diagram below. The magnetic field inside a long straight solenoid carrying current (A) is zero. (B) decreases as we move towards its end. (C) increases as we move towards its end. (D) is the same at all points. Choose the correct option. The correct answer is (d) The magnetic field inside a current-carrying solenoid is constant in magnitude and direction, and acts along the axis of the solenoid. Which of the following property of a proton can change while it moves freely in a magnetic field? (There may be more than one correct answer.)(A) mass (B) speed (C) velocity (D) momentumSOLUTION: The correct answers are (c) and (d). Each moving charged particle in a magnetic field experiences a force. The direction of force experienced by a positive charge (i.e., a proton) is given by Fleming’s left hand rule. The force acting on the proton would change both velocity and momentum. In an activity demonstrating the force acting on a current-carrying conductor placed in a magnetic field as shown in figure how do we think the displacement of rod AB will be affected if (A) current in rod AB is increased? (B) a stronger horse-shoe magnet is used? (C) length of the rod AB is increased? The displacement of the rod AB (A) will increase when the current in rod AB is increased. (B) will increase when a stronger horse-shoe magnet is used. (C) will increase when length of the rod AB is increased.Q 10. A positively-charged particle(alpha-particle)projected towards west is deflected towards north by a magnetic field. The direction of magnetic field is (A) towards south (B) towards east (C) downward (D) upwardSOLUTION: The correct answer is (d). Apply Fleming’s left-hand rule, we can infer that the direction of magnetic field is upwards. State Fleming’s left-hand rule.SOLUTION: Fleming’s left-hand rule state as follows: Stretch out the thumb, the forefinger, and the second(middle) finger of the left hand so that these are at right angles to each other. If the forefinger gives the direction of the magnetic field (N to S), the second (middle) finger the direction of current (+ to –), then the thumb gives the direction of the force acting on the conductor. Since the conductor will move in the direction of the force acting on it hence the thumb gives the direction of motion of the conductor. What is the principle of an electric motor?SOLUTION: An electric motor is based upon the magnetic effect of current. When an electric current is passed through a conductor placed at right angle to a magnetic field, a force perpendicular both to the magnetic field and the conductor acts on it. This makes the conductor move. The direction of motion of the conductor is given by Fleming’s left-hand rule.Q 13. What is the role of the split ring in an electric motor?SOLUTION: The role of split ring is to change the direction of current flowing through the coil after each half-rotation.Q 14. Explain different ways to induce current in a coil.SOLUTION: (a) By keeping the magnet in a fixed position and moving the coil towards and away from the magnet. (b) By pushing or pulling a bar magnet into or away from a coil. State the principle of an electric generator.SOLUTION: Electric generators are based on the principle of electromagnetic induction, that is, when a conductor is moved perpendicular to magnetic field or vice-versa, an induced current is produced.Q 16. Name some source of direct current.SOLUTION: Dry cell, Lead-acid batteryQ 17. Which sources produce alternating current?SOLUTION: AC generator, Thermal power station, Hydroelectric stations.Q 18. Choose the correct option. A rectangular coil of copper wires is rotated in a magnetic field. The direction of the induced current changes once in each (A) two revolutions (B) one revolution (C) half revolution (D) one fourth revolution The correct answer is (c).Q 19. Name two safety measures commonly used in electric circuits and appliances.SOLUTION: The safety devices that are used in electric circuits and appliances are, (a) Fuse (b) Earthing. MCBs are also used as safety device in electrical circuits.Q 20. An electric oven of 2 kW power rating is operated in a domestic electric circuit 220 V that has a current rating of 5 A. What result do you expect? Explain.SOLUTION: Rating of the oven = 2 kW Line voltage = 220 V Current drawn by the oven = 9.1 A Since the domestic circuit is rated for 5 A, and the oven draws a current of 9.1 A, the following might result. (a) The fuse (if there) will blow off. (b) The wiring may burn out. What precaution should be taken to avoid the overloading of domestic electric circuits?SOLUTION: (a) Do not connect appliances exceeding the total load capacity of the circuit. (b) Provide fuses/MCBs of proper rating. Which of the following correctly describes the magnetic field near a long straight wire? (A) The field consists of straight line perpendicular to the wire. (B) The field consists of straight lines parallel to the wire. (C) The field consists of radial lines originating from the wire. (D) The field consists of concentric circles centred on the wire.SOLUTION: The correct option is (d).Q 23. The phenomena of electromagnetic induction is (A) the process of charging a body (B) the process of generating magnetic field due to a current passing through a coil (C) producing induced current in a coil due to relative motion between a magnet and the coil (D) the process of rotating a coil of an electric motorSOLUTION: The correct option is (c).Q 24. The device used for producing electric current is called a: (A) generator (B) galvanometer (C) ammeter (D) motorSOLUTION: The correct option is (a).Q 25. The essential difference between AC generator and a DC generator is that (A) AC generator has an electromagnet while a DC generator has permanent magnet, (B) DC generator will generate a higher voltage, (C) AC generator will generate a higher voltage, (D) AC generator has slip rings while the DC generator has a commutator.SOLUTION: The correct option is (d).Q 26. At the time of short-circuit, the current in the circuit (A) reduces substantially (B) does not change (C) increases heavily (D) varies continuously.SOLUTION: The correct answer is (c).Q 27. State whether the following statements are true or false. (A) An electric motor converts mechanical energy into electrical energy. (B) An electric generator works on the principle of electromagnetic induction. (C) The field at the centre of a long circular coil carrying current will be parallel straight lines. (D) A wire with a green insulation is usually the live wire.SOLUTION: (a) False: An electric motor converts electric energy into mechanical energy. (d) False: A wire with a green insulation is usually the earth wire. List three sources of magnetic fields.SOLUTION: (i) Natural and artificial magnets (ii) Electromagnets (iii) A conductor, a coil and a solenoid carrying current (iv) Earth.Q 29. How does a solenoid behave like a magnet? Can you determine the north and south poles of a current carrying solenoid with the help of a bar magnet? Explain.SOLUTION: A current carrying solenoid behaves like a bar magnet and the polarities of its ends depend upon the direction of current flowing through it. In order to determine the polarities of its ends, place it in a brass hook and suspend it with a long thread so that it moves freely. Bring north pole of a bar magnet near one of its ends. In case the solenoid moves towards the bar magnet, that end of the solenoid is a south pole and in case the solenoid moves away from the magnet, that end of the solenoid is its north pole. The polarity of the other end of the solenoid can similarly be determined.Q 30. When is the force experienced by current-carrying conductor placed in a magnetic field is largest?SOLUTION: The force experienced by a current-carrying conductor placed in a magnetic field is the largest when the direction of the current is at right angles to the direction of the magnetic field.Q 31. Imagine that you are sitting in a chamber with your back to one wall. An electron beam, moving horizontally from back wall towards the front wall, is deflected by a strong magnetic field to your right side. What is the direction of the magnetic field?SOLUTION: The direction of current I is opposite to the direction electron beam as shown in figure. Since the beam is deflected to the right side, the force, F acting on the beam is as shown. Applying Fleming’s left hand rule, it is found that magnetic field, B is acting vertically downwards (i.e., perpendicular to the plane of the paper and directed inwards) as shown by ⊗. Draw a labelled diagram of an electric motor. Explain its principle and working. What is the function of a split-ring in an electric motor?SOLUTION: An electric motor is a device for converting electric energy into mechanical energy. Thus, an electric motor is the reverse of an electric generator. There are two types of electric motors : (i) AC motor and (ii) DC motor. We shall here be describing DC motor. The principle of a DC motor is very much different from that of an AC motor. It is important to remember that all the electric appliances like fan, air-conditioner, coolers, washing machines, mixers and blenders work on AC (house-hold power supply) and as such have AC motors installed in them. Principle : When a coil carrying current is placed in a magnetic field, it experiences a torque. As a result of this torque, the coil begins to rotate. Construction : It consists of the following five parts: 1. Armature : The armature abcd consists of a large number of turns of insulated copper wire wound over a soft iron core. 2. Field Magnet : The magnetic field B is supplied by a permanent magnet NS. 3. Split-ring or Commutator : These are two halve of the same metallic ring. The ends of the armature coil are connected to these halves which also rotate with the armature. 4. Brushes or Sliding Contacts : These are two flexible metal plates or carbon rods B1 and B2 which are so fixed that they constantly touch the revolving rings. 5. Battery : The battery consists of a few cells and is connected across the brushes. The brushes pass the current to the rings from where it is carried to the armature. Working : The working of a DC motor will be clear from the following discussion. (a) Let us suppose that the battery sends current to the armature in the direction shown in figure. Applying Fleming’s Left Hand Rule (Motor Rule), we find that arm ad experiences a force which is acting outwards and perpendicular to it and arm bc experiences a force which is acting inwards and perpendicular to it. These two forces form a couple whose moment (i.e., torque) makes the armature rotate in the clockwise direction. (b) After the armature has completed half a revolution (i.e., has turned through 180°), the direction of current in the arms ad and bc is reversed. Now arm bc experiences an outward force and arm ad experiences an inward force, as shown in figure. The armature thus continues to rotate about its axis in the same, i.e., clockwise direction. Split-ring in an electric motor takes the current from the battery and passes it on to the coil through the brushes after reversing its direction after every half revolution. The reversal of current in the coil reverses the direction of forces acting on the sides of the loop. Name some devices in which electric motors are used.SOLUTION: Electric fans, water-pumps, coolers, refrigerators, mixers, blenders, washing machines etc.Q 34. A coil of insulated copper wire is connected to a galvanometer. What would happen if a bar magnet is (i) pushed into the coil? (ii) withdrawn from inside the coil? (iii) held stationary inside the coil? (i) The magnetic field lines (flux) linked with the coil changes (i.e., increases). As a result of this, an induced current flows in the coil and the galvanometer shows a momentary deflection(say towards right) i.e., the needle of the galvanometer moves momentarily in one direction. (ii) The magnetic field lines (flux) linked with the coil changes (i.e., decreases). As a result of this, an induced current flows in the coil but in a direction opposite to that in case (i). (iii) When the magnet is held stationary in the coil, there will be a magnetic flux in the coil but it will remain constant. Since the magnetic flux does not change, there is no induced current in the coil and the galvanometer shows no deflection. Two circular coils A and B are placed close to each other. If the current in the coil A is changed, will some current be induced in the coil B? Given reason.SOLUTION: By changing current in the coil A, a current will be induced in the coil B which is placed close to A. This is due to the reason that magnetic field lines linked with A also get linked with B due to its being close to A. When the current in A changes, magnetic field lines linked with A change. Obviously, magnetic field lines linked with B also change. As a result of this, current is induced in the coil B. (This phenomenon is called mutual induction).Q 36. State the rule to determine the direction of a (i) magnetic field produced around a straight conductor carrying current. (ii) force experienced by a current-carrying straight conductor placed in a magnetic field which is perpendicular to it, and (iii) current induced in a coil due to its rotation in a magnetic field. (i) Right-Hand Thumb Rule : Imagine the straight conductor in your right hand such that the thumb points in the direction of current. The direction of curling of fingers of the right hand gives the direction of magnetic field lines. (ii) Fleming’s Left-Hand Rule (or Motor rule): Stretch the thumb, the first finger and the central finger of the left hand so that they are mutually perpendicular to each other. If the first (fore)finger points in the direction of the magnetic field, the central finger points in the direction of current, then the thumb points in the direction of motion of the conductor (i.e., direction of force on the conductor). (iii) Fleming’s Right-Hand Rule (or Dynamo rule) : Stretch the thumb, the first finger and the central finger of the right hand so that they are mutually perpendicular to each other. If the first(fore)finger points in the direction of magnetic field, the thumb points in the direction of motion of the conductor, then the central finger points in the direction of induced current. Explain the underlying principle and working of an electric generator by drawing a labelled diagram. What is the function of brushes?SOLUTION: An AC generator converts mechanical energy into electric energy. Principal : Whenever in a closed circuit (i.e., a coil), the magnetic field lines changes, an induced current is produced. Construction : It consists of the following four parts. 1. Armature : Armature (ABCD), also called the coil, consists of a large number of turns of insulated copper wire would over a soft iron core. It revolves around an axle between the two poles of a strong magnet. 2. Field Magnet : The magnetic field (B) is supplied by a permanent magnet in a small dynamo (also called a magneto) and by an electromagnet in case of a big commercial dynamo (usually called a generator). The poles of the magnet are shown as N-S in figure (a). 3. Slip Rings : R1 and R2 are two hollow metal rings held at different heights. The end D of the armature coil is connected to ring R1. The end C of the coil is passed through R1 without touching it and is connected to R2. These rings rotate with the rotation of the armature. 4. Brushes or Sliding Contact : B1 and B2 are flexible metal plates or carbon rods. These are called brushes or sliding contacts. B1 is in constant touch with R1 and B2 is in constant touch with R2. It is with the help of these brushes that the induced current is passed on from the armature and the rings to the external circuit containing a resistance, R and a galvanometer, G. Brushes are stationary i.e. these do not rotate with the rotation of the armature. Working : The working of an AC generator is clear from figure (a) and (b). As the armature is rotated about an axis (shown dotted), the magnetic flux linked with the armature changes. Therefore, an induced current is produced in the armature. (a) Let us suppose that the armature abcd is rotating anticlockwise so that the arm AD moves inwards and BC moves outwards. Applying Fleming’s right-hand rule, we find that the induced current in the armature and in the circuit is as shown in Fig. (a) due to which G shows deflection towards the right. (b) After the armature has turned through 180°, it occupies the position shown in Fig. (b). With the armature rotating in the same direction (i.e., anticlockwise), bc moves inwards and ad moves outwards. Thus, again applying Fleming’s right-hand rule, we find the induced current in the external circuit (R and G) flows in the opposite direction due to which the direction of deflection in the galvanometer is towards left. Thus, we see that the direction of induced current changes in external circuit after every half revolution of the armature, i.e., after the armature has turned through an angle of 180° from its initial position. Hence, the induced current is alternating in nature. When does an electric short-circuit occur?SOLUTION: Electric short-circuit occurs when the live wire and the neutral wire come in direct contact. This occurs when (i) the insulation of wires is damaged or (ii) there is a fault in the electric appliance. What is the function of an earth wire? Why is it necessary to earth metallic appliances?SOLUTION: Many electric appliances of daily use like electric press, heater, toaster, refrigerator, table fan etc. have a metallic body. If the insulation of any of these appliances melts and makes contact with the metallic casing, the person touching it is likely to receive a severe electric shock. This is due to the reason that the metallic casing will be at the same potential as the applied one. Obviously, the electric current will flow through the body of the person who touches the appliance. To avoid such serious accidents, the metal casing of the electric appliance is earthed. Since the earth does not offer any resistance, the current flows to the earth through the earth wire instead of flowing through the body of the person.
Breast cancer is one of the most common cancers in the world. Each year in the UK there are more than 55,000 new cases, and the disease claims the lives of 11,500 women. In the US, it strikes 266,000 each year and kills 40,000. But what causes it and how can it be treated? What is breast cancer? Breast cancer develops from a cancerous cell which develops in the lining of a duct or lobule in one of the breasts. When the breast cancer has spread into surrounding breast tissue it is called an ‘invasive’ breast cancer. Some people are diagnosed with ‘carcinoma in situ’, where no cancer cells have grown beyond the duct or lobule. Most cases develop in women over the age of 50 but younger women are sometimes affected. Breast cancer can develop in men though this is rare. Staging means how big the cancer is and whether it has spread. Stage 1 is the earliest stage and stage 4 means the cancer has spread to another part of the body. The cancerous cells are graded from low, which means a slow growth, to high, which is fast growing. High grade cancers are more likely to come back after they have first been treated. What causes breast cancer? A cancerous tumour starts from one abnormal cell. The exact reason why a cell becomes cancerous is unclear. It is thought that something damages or alters certain genes in the cell. This makes the cell abnormal and multiply ‘out of control’. Although breast cancer can develop for no apparent reason, there are some risk factors that can increase the chance of developing breast cancer, such as genetics. What are the symptoms of breast cancer? The usual first symptom is a painless lump in the breast, although most breast lumps are not cancerous and are fluid filled cysts, which are benign. The first place that breast cancer usually spreads to is the lymph nodes in the armpit. If this occurs you will develop a swelling or lump in an armpit. How is breast cancer diagnosed? - Initial assessment: A doctor examines the breasts and armpits. They may do tests such as a mammography, a special x-ray of the breast tissue which can indicate the possibility of tumours. - Biopsy: A biopsy is when a small sample of tissue is removed from a part of the body. The sample is then examined under the microscope to look for abnormal cells. The sample can confirm or rule out cancer. If you are confirmed to have breast cancer, further tests may be needed to assess if it has spread. For example, blood tests, an ultrasound scan of the liver or a chest x-ray. How is breast cancer treated? Treatment options which may be considered include surgery, chemotherapy, radiotherapy and hormone treatment. Often a combination of two or more of these treatments are used. - Surgery: Breast-conserving surgery or the removal of the affected breast depending on the size of the tumour. - Radiotherapy: A treatment which uses high energy beams of radiation focussed on cancerous tissue. This kills cancer cells, or stops cancer cells from multiplying. It is mainly used in addition to surgery. - Chemotherapy: A treatment of cancer by using anti-cancer drugs which kill cancer cells, or stop them from multiplying - Hormone treatments: Some types of breast cancer are affected by the ‘female’ hormone oestrogen, which can stimulate the cancer cells to divide and multiply. Treatments which reduce the level of these hormones, or prevent them from working, are commonly used in people with breast cancer. How successful is treatment? The outlook is best in those who are diagnosed when the cancer is still small, and has not spread. Surgical removal of a tumour in an early stage may then give a good chance of cure. The routine mammography offered to women between the ages of 50 and 70 mean more breast cancers are being diagnosed and treated at an early stage. For more information visit breastcancercare.org.uk, breastcancernow.org or www.cancerhelp.org.uk
This book draws on extensive research to provide a ground-breaking new account of the relationship between dialogue and children’s learning development. It closely relates the research findings to real-life classrooms, so that it is of practical value to teachers and students concerned that their children are offered the best possible learning opportunities. The authors provide a clear, accessible and well-illustrated case for the importance of dialogue in children's intellectual development and support this with a new and more educationally relevant version of socio-cultural theory, which explains the fascinating relationship between dialogues and learning. In educational terms, a sociocultural theory that relates social, cultural and historical processes, interpersonal communication and applied linguistics, is an ideal way of explaining how school experience helps children learn and develop. By using evidence of how the collective construction of knowledge is achieved and how engagement in dialogues shapes children's educational progress and intellectual development, the authors provide a text which is essential for educational researchers, postgraduate students of education and teachers, and is also of interest to many psychologists and applied linguists. Table of Contents 1. Why Dialogue? 2. Learning to Collaborate, Collaborating to Learn 3. Language for Getting Things Done 4. Studying Thinking and its Development as Situated Dialogue 5. A Dialogic Theory of Learning and Development 6. Children Actively Make Sense of Their World...but They Need Guidance to Do So 7. Conclusions Neil Mercer is Professor of Education at the University of Cambridge, UK. . Karen Littleton is Professor of Psychology in Education at The Open University, UK.
The moon is around 240,000 miles away from the Earth. Our moon is a pretty big object. It's big enough to be a respectable planet in its own right, if it were orbiting the sun instead of the Earth. (Actually, it is orbiting the sun in a nearly perfectly circular orbit, that the Earth only slightly perturbs... but that's a topic for another day.) The Moon is a quarter the diameter of the Earth. Only Pluto has a satellite that is larger, in proportion to the size of the planet it orbits. Mercury is the smallest planet in the Solar System and would appear to be the same size as the moon. The red planet is almost exactly twice the size of the Moon, so it would appear twice as big in the Earth's sky. Venus is three and a half times larger than the Moon and would be six times brighter and is the hottest planet, with surface temperatures over 400 degrees. Neptune is more than 14 times larger than the Moon would be an enormous blue sphere in the night sky. Uranus is about 14 times larger than the moon and would look like this. Saturn is about 35 times larger than the Moon and the rings would stretch nearly from horizon to horizon. Jupiter is 40 times larger than the Moon and is so huge we'd not be able to see the north and south poles of the planet.
This experiment is done in a dark room to teach a child about shadows. - Torch / Lamp - Cardboard / Thick Paper - Wall (preferably plain) What to do: - Cut a creative shape out of cardboard. - Shine a torch or lamp on the card. - Hold it in front of you, with the wall behind you. The Science Factor: The holes in the cardboard let the light of the torch / lamp through but the card itself blocks the light. You get a shadow on the wall in the shape of the card. A shadow is made because light cannot get through the cardboard. Hints and Tips: - Watch what happens when you move the shape closer and further from the lamp. - Use your hands to create different shadows on the wall.
Montessori education offers a broad vision of education as an “aid to life”. This method succeeds because it draws on the natural development of the child. Each child’s inner directives are guided towards wholesome growth. The freedom of choice inherent within the prepared classroom environment promotes a lifelong love of learning in the child. Montessori classrooms provide a prepared environment where children can go to do purposeful work. Dr. Montessori developed the curriculum based on the neurological and physiological needs of the child at each stage of development. Then she broke the curriculum up into concrete activities which she placed beautifully and logically within the Montessori classroom. The role of the Montessori teacher is to demonstrate the use of the materials and activities based on observation and careful assessment of the child’s needs. The ultimate goal of the teacher is to intervene less and less as the child develops. The AMI Montessori teacher receives specialized training and education so that he or she can develop the skill of knowing when to intervene and when to observe. In this multi-age environment the children develop independence, creativity, responsibility and a sense of their place as a contributing member of their classroom community. In a Montessori classroom, children are given the opportunity to develop their powers of concentration (from concentro which means being with your center), and joyful self-discipline. The true discipline of the child comes from within as a freely chosen response to the environment. The Montessori method develops the personality of the child – not just the intellect. Maria Montessori was the first woman doctor in Italy, in 1896. Through scientific observation, she developed a system of learning based on her conclusions about how children relate with one another, learn through the use of specific materials, and go through universal phases of development. Dr. Montessori’s philosophy was based on the principle that all children naturally develop in stages, called planes of development. From birth to age 6, children are in the first plane, where they are sensorial explorers that absorb the world around them. Children in the second plane, ages 6 through 12, become conceptual explorers and abstract thinkers. They are eager to learn and experience the world and their role in it. Using her background in psychology, and her belief that society could be bettered through the education of children – she developed her approach to education. She also articulated universal laws of development that are inherent to children of all races and cultures. Her timeless method continues to be highly respected internationally. MONTESSORI VS. TRADITIONAL EDUCATION Does the Montessori curriculum cover the same subjects as other schools? Unlike mainstream educational approaches, Montessori education serves the whole human being, and has faith in the child’s universal love of learning. Therefore, subject areas such as art, spanish, music, and science are integrated into the prepared environment of the classroom for each child’s exploration.
Local Curvature of Space According to Einstein’s theory of general relativity, massive objects warp the spacetime around them, and the effect a warp has on objects is what we call gravity. So, locally, spacetime is curved around every object with mass. Overall Curvature of Space Mass also has an effect on the overall geometry of the universe. The density of matter and energy in the universe determines whether the universe is open, closed, or flat. If the density is equal to the critical density, then the universe has zero curvature; it is flat. You can imagine a flat universe like a sheet of paper that extends infinitely in all directions. A universe with density greater than the critical density has positive curvature, creating a closed universe that can be imagined like the surface of a sphere. And if the universe’s density is less than the critical density, then the universe is open and has negative curvature, like the surface of a saddle. Measurements from the Wilkinson Microwave Anisotropy Probe (WMAP) have shown the observable universe to have a density very close to the critical density (within a 0.4% margin of error). Of course, the observable universe may be many orders of magnitude smaller than the whole universe. But the part of the universe we can observe appears to be fairly flat.
an X Ray X rays are a very penetrating form of electromagnetic radiation. X rays pass through the soft tissue of the body but are largely stopped by bones and other more dense tissues. This makes x rays very useful for medical and dental purposes, as you know. A schematic view of an x-ray tube and a driver circuit is given in Figure VI.1. A filament warms the cathode, freeing electrons. These electrons are accelerated by the electric field established by a high-voltage power supply connected between the cathode and a metal target. The electrons accelerate in the direction of the target. The rapid deceleration when they strike the target generates x rays. Each electron will emit one or more x rays as it comes to rest. An x-ray image is essentially a shadow; x rays darken the film where they pass, but the film stays unexposed, and thus light, where bones or dense tissues block x rays. An x-ray technician adjusts the quality of an image by adjusting the energy and the intensity of the x-ray beam. This is done by adjusting two parameters: the accelerating voltage and the current through the tube. The accelerating voltage determines the energy of the x-ray photons, which can’t be greater than the energy of the electrons. The current through the tube determines the number of electrons per second and thus the number of photons emitted. In clinical practice, the exposure is characterized by two values: “kVp” and “mAs.” kVp is the peak voltage in kV. The value mAs is the product of the current (in mA) and the time (in s) to give a reading in mA . s. This is a measure of the total number of electrons that hit the target and thus the number of x rays emitted. Typical values for a dental x ray are a kVp of 70 (meaning a peak voltage of 70 kV) and mAs of 7.5 (which comes from a current of 10 mA for 0.75 s, for a total of 7.5 mAs). Assume these values in all of the problems that follow. If the distance between the cathode and the target electrode is approximately 1.0 cm, what will be the maximum acceleration of the free electrons? Assume that the electric field is uniform. Solution Introduction: F Acceleration and force are related as, a =m , where a is acceleration, F is the force on an electron and m is its mass. We know the charge of an electron, so if we can calculate force if we can calculate the electric field strength. Electric field strength can be calculated if voltage and separation between electrodes is given. Step 1: Electric field, E = Voltage …..(1) Separation between the electrodes Given that, Voltage = 70kV Distance between electrodes = 1.0 cm 2 = 10 m Therefore, Electric field, E =702 (from equation 1) 10 m E = 70×1000×10 2 m 6V E = 7×10 m …..(2)
Send Feedback to MSDE’s Mathematics Team In previous grades, students were asked to draw triangles based on given measurements. Students also have prior experience with rigid motions: translations, reflections, and rotations and have used these to develop notions about what it means for two objects to be congruent. In this unit, students establish triangle congruence criteria, based on analyses of rigid motions and formal constructions. Students use triangle congruence as a familiar foundation for the development of formal proof. Students prove theorems—using a variety of formats—and solve problems about lines, angles, triangles, quadrilaterals, and other polygons. Students also apply reasoning to complete geometric constructions and explain why constructions work. A question is essential when it stimulates multi-layered inquiry, provokes deep thought and lively discussion, requires students to consider alternatives and justify their reasoning, encourges re-thinking of big ideas, makes meaningful connections with prior learning, and provides students with opportunities to apply problem-solving skills to authentic situations. Congruence, Proof and Constructions Additional information such as Teachers Notes, Enduring Understandings,Content Emphasis by Cluster, Focus Standards, Possible Student Outcomes, Essential Skills and Knowledge Statements and Clarifications, and Interdisciplinary Connections can be found in this Lesson Unit. The lesson plan(s) have been written with specific standards in mind. Each model lesson plan is only a MODEL - one way the lesson could be developed. We have NOT included any references to the timing associated with delivering this model. Each teacher will need to make decisions related ot the timing of the lesson plan based on the learning needs of students in the class. The model lesson plans are designed to generate evidence of student understanding. This chart indicates one or more lesson plans which have been developed for this unit. Lesson plans are being written and posted on the Curriculum Management System as they are completed. Please check back periodically for additional postings. Discovering Triangle Congruence CCSC Alignment: G.CO.6, G.CO.7, G.CO.8 This lesson plan focuses on the concept of congruence and its connection to rigid motion. (i.e. Objects in space which can be transformed in an infinite number of ways and describing/analyzing those transformations.) The lesson seed(s) have been written with specific standards in mind. These suggested activity/activities are not intended to be prescriptive, exhaustive, or sequential; they simply demonstrate how specific content can be used to help students learn the skills described in the standards. Seeds are designed to give teachers ideas for developing their own activities in order to generate evidence of student understanding. This chart indicates one or more lesson seeds which have been developed for this unit. Lesson seeds are being written and posted on the Curriculum Management System as they are completed. Please check back periodically for additional postings. Flash Mob Dance CCSC Alignnment: G.CO.2 Practice Activity: Students who learn best through kinesthetic means will have the opportunity to move while reviewing what they know about various transformations. Developmental Activity: Students will compare and contrast rigid transformations and transformations that are not rigid as well as the various specific types of transformations. Flip and Slide CCSC Alignnment: G.CO.5, G.CO.6 Practice Activity: This is a computer game that could be used to provide practice on transformations to students who respond well to using technology. Finding What Doesn’t Change CCSC Alignnment: G.CO.6 Investigation: This investigation can be used in direct instruction or with students in small groups or partners. Students answer the questions provided, while investigating rotational transformations on the computer. Special Angle Pair Theorems CCSC Alignnment: G.CO.9 Warm-Up/Intervention: In 8th grade students use informal arguments to establish facts about the angles created when parallel lines are cut by a transversal. This activity helps to bring this knowledge back to the forefront. This information is needed to prove theorems about lines and angles. CCSC Alignnment: G.CO.10 Practice Activity: The problems found in this document should not be used all at one time. The problems should be used one or two at a time to provide distributed practice over time. Using Triangle Congruence in Proofs Practice Activity: This activity will provide students with practice on completing proofs using a variety of formats. It is highly recommended that these problems be used one or two at a time for distributed practice over time to help student maintain skills. Triangle Sum Theorem Practice Activity: This lesson seed describes an activity which requires students to complete a flow chart proof and a two-column proof while proving the Triangle Sum Theorem and the Exterior Angle Theorem. What’s My Angle Investigation: Introduce this activity after proof of the interior angle sum theroem for triangles. Students will use sum of the interior angles of a triangle to determine the sum of the interior angles of any convex polygon. Midsegments of Triangles and Trapezoids Investigation/Carousel Practice Activity: The beginning of this lesson seeds provides an investigation which helps students develop conjectures about midsegments. The activity can be followed with a class discussion to solidify these geometric relationships. CCSC Alignnment: G.CO.9, G.CO.10, G.CO.11 Developmental Activity: This activity could be used to help students begin thinking about how the logical order of a sequence of statements is necessary for a process to make sense. Completing this activity could serve as motivation for a lesson which targets proofs. CCSC Alignnment: G.CO.12 Resource:This lesson seed serves as a resource rather than an activity. It provides step-by-step directions to make geometric constructions using a compass and straightedge. Students may elect to refer to this document as needed when required to make formal geometric constructions. CCSC Alignnment: G.CO.9, G.CO.12 Investigation: This lesson seed describes three different activities which allow students to first construct a perpendicular bisector of a segment and then discover that all points on the perpendicular bisector of a segment are equidistant from the endpoints of the segment. Finding a Buried Time Capsule Application: This lesson seed could be used as an application after students have studied the Perpendicular Bisector Theorem.
DNS Full Form: The full form of DNS is referred to as the Domain Name System. It is a set up of a web, which allows the user to contact the correct server by entering the correct uniform resources locator into the web browser. It converts internet domain and hostnames to IP addresses and vice versa. For example in WWW.cnn.com, ‘www’ is the hostname, ‘cnn.com’ is the domain name and ‘220.127.116.11’ is the IP address of CNN. DNS Full Form It is a human-readable name—like yahoo.com—that a user types in a web browser URL field. The domain names are managed by The Internet Corporation for Assigned Names and Numbers (ICANN). Top-Level Domain (TLD) It is the last part of a domain name. For example, the .com in yahoo.com is the Top Level Domain. Some of the most common TLDs include .com, .net, org, and .info. Country code TLDs represents particular geographical locations. For example: ‘in’ represents India, ‘eu’ – European Union, ‘gov’ – U.S. government agencies. Second Level Domain It is the part of a domain name which comes just before the LTD. A subdomain is created to identify specific content areas of a web site. For example, the ‘erp’ in erp.sap.com It is like a phone book which contains the names of domain and their associated IP addresses. How DNS Works When a user enters a domain name into the browser, the computer’s DNS client checks for information in a local cache. If the name is not found, then the request is sent to the DNS server. The DNS server then forwards the request to a DNS root name server. The name server looks in the domain record for the domain name, gets the corresponding IP address for a web server and returns the IP address to the DNS server. It then returns the IP address to the web browser. The web browser sends a request for the searched domain name to the IP address that it received from the DNS server. The web server at the IP address returns the web page for the domain name to the web browser, and the web browser displays the page. - DNS is a centralized system that helps to find the website using an internet browser like chrome, safari, firefox, etc. - There is no need to remember large numbered addresses as the domain name provides links when the name is given. - DNS is used as a form of an additional layer of security. - It enables the requests to be answered to the next closest node in the case of maintenance or downtime, it is smarter & it offers automatic corrections of typed words. - When the DNS server cannot find the correct IP address, the website will not load, As the computers communicate via IP addresses & not host-names. - ICANN can control the DNS root registry making DNS a centralized system - Malware hijacks some DNS servers to redirect popular websites to ones that are full of advertisements or fake virus websites. To prevent this antivirus program should be installed. People Also Reading:
Learn something new every day More Info... by email Fasteners can include nuts, bolts and washers that are used to connect metal parts. They are used as connectors in vehicles, aircraft and boats. Aluminum metal can be soft, making it difficult to use for fastening objects, because the untreated metal can deform or break. A process called anodizing creates a much harder metal finish, and anodized fasteners are both strong and resistant to wear or corrosion. Anodizing is an electrochemical process, using both electrical current and an acid chemical bath, to create a hard finish on anodized fasteners. The process involves creating a layer of aluminum oxide on the outer surface of the parts. Rather than a coating such as paint, the anodized finish is a molecular bond to the aluminum metal beneath, which results in a very durable finish. The process uses an acid bath, which provides oxygen for the chemical reaction. Anodized fasteners are connected to one side of an electrical circuit, and a separate metal electrode is submerged in the bath. When the parts enter the acid, an electrical circuit is established and the aluminum parts are oxidized at the surface to form aluminum oxide. Anodizing involves the rapid oxidation, or rusting, of the aluminum surface of the parts. Unlike normal rust, the aluminum oxide forms a very thin, hard crystal structure that becomes a new surface. These surfaces may wear off over time, but can provide long service life with minimum deterioration, particularly when compared to pure aluminum. It is important when fastening metals to use the same metals for all parts, to avoid galvanic corrosion. This occurs when a small electrical current passes between different metals, and softer metals like aluminum can be more quickly damaged by galvanic action. In addition to strengthening the metal, anodized fasteners are less subject to galvanic corrosion, because the aluminum oxide finish can block the electric current. Anodized fasteners are often used to customize automobiles, and one reason is that the anodized finish can easily be colored to suit the user. The aluminum oxide finish is porous, which means it contains many small voids or openings, rather than being perfectly smooth. These voids can accept dyes or colored pigments, allowing the parts to be customized in a wide variety of colors. The color becomes a permanent part of the coating, and no further painting is needed to maintain it. Other metals can be anodized, including titanium, which improves their corrosion resistance in aircraft applications where parts are exposed to wide ranges of temperature and humidity. Different acid solutions can be used to provide a range of oxide coatings, depending on the part specifications. Sulfuric acid is the most common type of anodizing, and can create both thin and relatively thick coatings. Chromic acid is used when very thin coatings are needed, particularly for parts requiring a very tight fit, known as close tolerances. One of our editors will review your suggestion and make changes if warranted. Note that depending on the number of suggestions we receive, this can take anywhere from a few hours to a few days. Thank you for helping to improve wiseGEEK!
This article needs additional citations for verification. (September 2018) (Learn how and when to remove this template message) Narrative history is the practice of writing history in a story-based form. It tends to entail history-writing based on reconstructing series of short-term events, and since the influential work of Leopold von Ranke on professionalising history-writing in the nineteenth century has been associated with empiricism. The term narrative history thus overlaps with the term histoire événementielle ('event-history') coined by Fernand Braudel in the early twentieth century, as he promoted forms of history-writing analysing much longer-term trends (what he called the longue durée). Though history is considered a social science, the story-based nature of history allows for the inclusion of a greater or lesser degree of narration in addition to an analytical or interpretative exposition of historical knowledge. It can be divided into two subgenres: the traditional narrative and the modern narrative. Traditional narrative focuses on the chronological order of history. It is event driven and tends to center upon individuals, action, and intention. For example, in regard to the French Revolution, a historian who works with the traditional narrative might be more interested in the revolution as a single entity (one revolution), centre it in Paris, and rely heavily upon major figures such as Maximilien Robespierre. Conversely, modern narrative typically focuses on structures and general trends. A modern narrative would break from rigid chronology if the historian felt it explained the concept better. In terms of the French Revolution, a historian working with the modern narrative might show general traits that were shared by revolutionaries across France but would also illustrate regional variations from those general trends (many confluent revolutions). Also this type of historian might use different sociological factors to show why different types of people supported the general revolution. Historians who use the modern narrative might say that the traditional narrative focuses too much on what happened and not enough on why and causation. Also, that this form of narrative reduces history into neat boxes and thereby does an injustice to history. J H Hexter characterized such historians as "lumpers". In an essay on Christopher Hill, he remarked that "lumpers do not like accidents: they would prefer them vanish...The lumping historian wants to put all of the past into boxes..and then to tie all the boxes together into one nice shapely bundle." Historians who use traditional narrative might say that the modern narrative overburdens the reader with trivial data that had no significant effect on the progression of history. They believe that the historian needs to stress what is consequential in history, as otherwise the reader might believe that minor trivial events were more important than they were. - A Dictionary of Cultural and Critical Theory, ed. by Michael Payne and Jessica Rae Barbera, 2nd edn (Chichester: Wiley-Blackwell, 2013), s.v. 'Braudel, Fernand' (p. 90). White, Hayden (1 March 1984). "The Question of Narrative in Contemporary Historical Theory" (PDF).
Pediatric dentistry is an age-defined specialty that provides both preventive and therapeutic dental care for infants, children and adolescents It is very important that primary teeth are kept in place until they are lost naturally. These teeth serve a number of critical functions. Primary teeth: - Maintain good nutrition by permitting your child to chew properly any tartar that has built up - Are involved in speech development - Help the permanent teeth by saving space for them. A healthy smile can help children feel good about the way they look to others. Baby teeth should be cleaned as soon as they erupt. Clean your baby’s teeth with a soft washcloth or gauze after every bottle or meal. Baby teeth should be brushed using a pea-sized amount of toothpaste. Use water without fluoride until approximately six months of age. The first dental visit should occur shortly after the first tooth erupts and no later than the child’s first birthday. Beginning tooth and mouth examinations early may lead to detection of early stages of tooth decay that can be easily treated. Children’s teeth should be brushed after they are given medicine. Acids contained in medicines may eat away at tooth enamel, which serves as a natural protective coating for the teeth. By age 4 or 5, children should be able to brush their own teeth twice a day with supervision until about age seven to make sure they are doing a thorough job. Flossing removes plaque between the teeth where a toothbrush can’t reach. Flossing should begin when any two teeth touch. You should floss the child’s teeth until he or she can do it alone. Good oral hygiene removes bacteria and the left over food particles that combine to create cavities. For infants, use a wet gauze or clean washcloth to wipe the plaque from teeth and gums. Avoid putting your child to bed with a bottle filled with anything other than water. The American Academy of Pediatric Dentistry (AAPD) recognizes the benefits of xylitol on the oral health of infants, children, adolescents, and persons with special health care needs. The use of XYLITOL GUM by mothers (2-3 times per day) starting 3 months after delivery and until the child was 2 years old, has proven to reduce cavities up to 70% by the time the child was 5 years old. Replace toothbrushes every two to three months. For more information or to schedule an appointment, give us a call today at (415) 567-2900
The Historical Background of the Feast of Nativity Determining the date of the feast The Church did not celebrate the Nativity of Christ until the fourth century. Then, in the fourth century, the date of this feast was determined and it started to be celebrated. At that time some theological discussions were taking place in the ecumenical councils related to Christology: His divinity, incarnation, and redemption. Together with these discussions, other organisational matters of the Church were discussed and determined; some of these were related to the feasts. As a result, the season of incarnation was set. This season starts with the Advent and concludes with the Nativity feasts which are also referred to as the ‘Theophany Feasts’. As to how the date of this feast was determined, whether the 25th of December according to the Gregorian calendar or the 7th of January according to the Julian calendar, it is important to highlight that these 13 days difference are merely an astronomical difference resulting from calculating the dates either according to the Solar year or the Lunar year. This means that it is the same day; the 25th of December and the 7th of January are the exact same day calculated according to the Gregorian calculations in one instance and according to the Julian calculations in the other instance. Yet, the question still remains and that is: why this particular date? I shall clarify this after discussing some points of views which have recently appeared regarding the timing of Christmas. These views cause a lot of confusion and are of no value and so it is important to discuss them and clarify them.
What Are Epileptic Seizures and What Causes Them? Please note that this information does not qualify you as an official first aider, and Virtual College advise calling 999 in the first instance at the scene of an emergency. This material and any associated assessments do not constitute a qualification or accreditation as an official first aider. All content provided is for general information only. Virtual College advocate dialling the emergency services before attempting any form of first aid. What Are Epileptic Seizures and What Causes Them? A person can suffer from an epileptic seizure (also frequently known as an epileptic fit) when they experience abnormal electrical activity in the brain. This can be a serious medical condition, and any member of the population could potentially experience an epileptic seizure at some point in their lives. In this article, we’re going to go through exactly what happens when an epileptic fit occurs, and how they can be triggered. Note: Epileptic seizures and epilepsy should not be confused, though they can be related. The phrase ‘epileptic seizure’ refers to the seizure event itself, but those people with epilepsy have a condition whereby they are susceptible to seizures that begin in the brain. What Happens During an Epileptic Seizure? Epileptic seizures happen when there is excessive or abnormal behaviour in neural activity occurring in any part of the brain. These can affect normal brain function, causing everything from auditory hallucinations and visual disturbances, to severe physical reactions. They can be one-off events, or commonplace symptoms of a particular condition, and can range from being minor to the point that no medical attention is required, to needing lifelong management. What Types of Seizure Are There? There are actually two types of seizure that can occur as a result of this abnormal brain activity. They are focal and generalised seizures, and it’s important to know the difference, because they manifest themselves differently, and can have different treatment paths. Focal seizures, as their name suggests, begin in one part of the brain, which means that their effects can be varied depending on which part of the brain has been affected. They can range from fairly minor events in which the person remains conscious and remembers the seizure, having experienced phenomena such as hallucinatory lights and smells, to events whereby the person becomes confused or unconscious, and may engage in strange movements known as automatisms. This can include repetitive movements such as lip smacking. Generalised seizures however affect the entire brain, and in almost all cases will result in a period of unconsciousness that the person does not remember. During this, there are a variety of things that can happen: - Tonic seizures - A person suffering from this kind of seizure will experience stiffness or contractions throughout the body, and may fall over. Generally, episodes of this type will only be brief. - Clonic seizures - Rather than stiffness, a person experiencing a clonic seizure will convulse and shake. - Tonic-clonic seizures - A combination of both a tonic and clonic seizure, this is one of the most common types of epileptic seizure, and will make a person experience contractions and arching of the back for up to half a minute, before shaking commences. It can take up to half an hour to fully recover from this type of seizure. - Myoclonic seizures - These are muscle spasms that occur sporadically in places throughout the body. - Atonic seizures - The opposite to tonic seizures, in this situation, a person’s muscles will all relax at once, which often causes them to collapse forwards. They are sometimes known as ‘drop attacks’. - Absence seizures - Also known as petit mal seizures, can be fairly minor with no loss of consciousness, and generally involve disorientation, confusion, and minor muscle movements such as turning of the head. Note: focal seizures can sometimes progress to become generalised seizures. What Causes an Epileptic Seizure? There are many potential triggers for an epileptic seizure, and it is unfortunately not always possible to be sure exactly why one has occurred. However, there are numerous described causes, and they tend to be more or less likely based on the person’s age. Some of the major triggers include the following: - Brain tumours - Central nervous system (CNS) infections - Severe dehydration - Alcohol intoxication and other drug overdoses - Sleep deprivation - Complications during pregnancy Contrary to popular belief, epileptic seizures triggered by light activity (such as strobe lighting) are very uncommon indeed, and generally account for only a very small fraction of events. How Are They Treated? To find out more about how patients suffering from an epileptic seizure can be cared for, and when emergency medical attention should be sought, then please read our dedicated first aid article on the subject here. We also recommend visiting our page on the Primary Survey course that we offer. This survey is intended to cover best practice response to a first aid situation.
It’s fair to say math is not everyone’s favorite subject. In fact, for many people, the feelings of tension and anxiety that arise when trying to solve a mathematical problem can be all-consuming. This is known as math anxiety — and this feeling of being a failure at math can affect people’s self-worth for years to come. For those who suffer from math anxiety, it can be difficult to shift from a mindset of failure to a more positive outlook when it comes to dealing with numbers. This is why, for many people, math anxiety can become a lifelong issue. But research shows that if teachers tackle math anxiety in the classroom and encourage children to try to approach a problem in a different way — by shifting their mindset — this can be an empowering experience. This is especially the case for pupils from a disadvantaged background. US psychology professor, Carol Dweck, came up with the idea of “mindset theory.” Dweck realized that people can often be categorized into two groups, those who believe they are bad at something and cannot change, and those who believe their abilities can grow and improve. This formed the basis of her mindset theory, which states that some people have a “fixed mindset,” meaning they believe their ability to be set in stone and unable to be improved. Other people have a “growth mindset,” meaning they believe their ability can change and improve over time with effort and practice. Jo Boaler, the British education author and professor of mathematics education, applied mindset theory to mathematics, subsequently naming her recommendations “mathematical mindsets.” She has used this theory to encourage learners to develop a growth mindset in the context of mathematics. The idea is that the problems themselves can help to promote a growth mindset in pupils — without them having to think about their mindset intentionally. New Ways of Thinking But while this all sounds well and good, one of the issues with mindset theory is that it is often presented in terms of brain plasticity or the brain’s ability to grow. This has lead to complaints about a shortage of neurological evidence supporting mindset theory. Our latest research aimed to address this lack of neurological research. Generally speaking, for every problem in mathematics, there is more than one way to solve it. If someone asks you what three multiplied by four is, you can calculate the answer either as 4+4+4 or as 3+3+3+3, depending on your preference. But if you have not developed sufficient mathematical maturity or have math anxiety, it can prevent you from seeing multiple ways of solving problems. But our new study shows that a “growth mindset” can make math anxiety a thing of the past. We measured participants’ motivation to solve mathematical problems by asking about motivation both before and after each problem was presented. We also measured participants’ brain activity, specifically looking at areas associated with motivation, while they solved each problem. This was done using an electroencephalogram (EEG) which records patterns of activation across the brain. In our research, we phrased questions in different ways to assess how question structure may affect both our participants’ ability to answer the questions and their motivation while tackling math problems. Each question appeared in two formats: one of typical mathematical teaching and another adhering to the recommendations of mathematical mindset theory. Both questions asked essentially the same question and had the same answer, like in the following simplified example: “Find the number which is the sum of 20,000 and 30,000 divided by two” (a typical mathematical problem) and “Find the midpoint number between 20,000 and 30,000” (an example of a mathematical mindset problem). Our study provides two important findings. The first is that participants’ motivation was greater when solving mathematical mindset versions of problems compared to the standard versions — as measured by their brain response when solving the problems. It is assumed this is because the mathematical mindset wording encourages students to treat numbers as points in the space and manipulate spatial constructions. The second is that participants’ subjective reports of motivation were significantly decreased after attempting the more standard math questions. Our research is immediately actionable in that it shows how opening up problems so that there are multiple methods to solving them, or adding a visual component, allows learning to become an empowering experience for all students. So for people with math anxiety, you will be relieved to know that you are not innately “bad” at math and your ability is not fixed. It is actually just a bad habit you have developed due to bad teaching. And the good news is, it can be reverted.
During the year, students will use a variety of equipment to build on their knowledge of technology which today develops from an early age and to extend their practical technological skills. Through technology such as iPads and digital recording devices (video, still and audio) students will be able to use different source materials to develop their ideas and express their creations via a variety of means, for example, apps and other publishing avenues, such as animations, presentations and videos. Students will come to an understanding of how computing systems work through developing their interface skills, via mouse, keyboard and touch-screen. Students will also develop a familiarity with coding through the utilisation of simple programmable / sequencing technology, such as Bee-Bots and online resources, such as Purple Mash. E-safety is taught throughout the year and is linked to safety in real-life, ensuring that pupils know how to stay safe online and know the steps to take if they are feeling unsafe. Guide to Guided access You can view some of our Purple Mash ICT work here!
In monkeys and large apes, Mycobacterium tuberculosis, M bovis, and M avium complex can cause severe disease of the lungs and other organs. Epidemics in primate colonies may be caused by contact with infected human caregivers. Transmission is usually by aerosol with respiratory infection, but the oral route is also possible. Bacilli may also be shed in urine. Old tuberculin is used in skin tests in preference to purified protein derivative (PPD), because it provides greater sensitivity in detecting animals infected with M tuberculosis or M bovis. Biologically balanced PPDs prepared from M bovis or M avium can be injected intradermally at separate sites on the abdomen to conduct a comparative test. Skin tests are observed at 24, 48, and 72 hr for induration and swelling. Tuberculins prepared for use in people are not of sufficient potency to elicit a response in nonhuman primates. Treatment of cases of tuberculosis in nonhuman primates has been attempted using drugs that have had success in people, eg, isoniazid, ethambutol, and rifampin. Drug sensitivity tests should be conducted to determine sensitivity of isolates. Efficacy is limited, and there are overriding arguments against therapy, based on the removal of infected animals, zoonotic risks, and the danger of developing drug resistance. Exacerbations may occur.
This is the first of three fairly intense lessons covering the fundamentals of solar energy. You will need to distill a lot of information and work hard to internalize the key topics. Make sure that you use the discussion forums to communicate with your peers, and be sure to ask questions. Most of us have learned bits and pieces of the following materials, but never together in one setting. And for some of us, this is the very first time we are learning to juggle all the balls that tie together solar energy. You can do it! Time and Space are related! This lesson will discuss the tools needed to evaluate spatial and temporal relationships: - of the Sun relative to the Earth; - of the Observer on the surface of Earth relative to the Sun at any given time; - while identifying the angles used to describe the orientation of a Solar Energy Conversion System (SECS) surface relative to the moving Sun; - also identifying the times that local shadows might obscure our SECS. We will use sun charts to analyze shadows with respect to solar collectors. Just like with navigation in a ship or an airplane, time and space relations are linked together in Solar Energy and can be represented and communicated as geographic information. We input that geographic information in terms of angles and use key relations from spherical trigonometry to make time and space relations easy to calculate with a computer. For our purposes: angles = coordinates in space and time. The tools we develop are going to explain the sun’s position relative to any point on the surface of the Earth. Once developed, our useful equations can also be applied to estimate the time and location of shadows that block SECSs or tracking technologies for SECSs. You will observe substantial mathematical relations in this lesson, and you will be expected to demonstrate your skill at applying them to solar problems in shading assessment. These equations are at the core of software like SAM, and a student completing this course should be very familiar with their application. Stick with it!
What is drinking water made of, besides water The visualization explores the elements contained in a glass of drinking water (above) and then drills down to each of the 20 Italian county seats (below). On top, the three glasses show the 38 elements that are regulated by law: in grey are the legal thresholds, color-coded the real quantities contained in the water. The 13 colors represent the most common elements between those published by the county seats’ water managers (but Catanzaro, whose data wasn’t available). At the bottom, the details of the 20 county seats: the circumference represents the legal threshold (no standard for calcium, magnesium and potassium). The length of the ray is the value of the element; in particular the one that is linked to the light blue square is the Total Dissolved Solids (measure of mass of residues left when evaporating a liter of water). In the square part are represented: the pH (numeric scale used to specify the acidity or basicity of an aqueous solution), the conductivity (ability to conduct electricity through water: the more concentration of ions the higher the conductivity) and hardness (content of calcium and magnesium’s salts). Available for purchase here.

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