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Ever got to grips with a problem? Picked up a new skill? Grasped a difficult concept? The language of learning is full of references to parts of the body outside the brain. Perhaps that’s because these phrases hint at something deeper. Researchers are discovering that learning is easier, quicker and more long-lasting if lessons involve the body as well as the mind – whether it’s gesturing with the arms or moving around a room. Can these insights enhance teaching and learning in the future? And should it inform the way technology is employed in the classroom? In some ways, the idea that the body can aid learning should come as no surprise. Consider that many of us probably began to understand basic arithmetic by counting on our fingers before learning to count in our head instead. “In the past, people have argued that as we learn we become more able to think abstractly,” says Andrew Manches, a teacher turned psychologist at the University of Edinburgh in the UK. “Young children depend on physical objects to help them, but if I’m asked in a meeting now to work out a calculation and I get out a set of blocks to help me – obviously I’m going to look silly.” Conventional thinking might suggest that teachers should help wean children off physical objects and body gestures to prepare them for the adult world. But in truth, the physical world never really leaves our thinking. For example, when we process verbs such as lick, kick and pick, medical scanners show that the parts of our brain that control the muscles in our face, legs and hands, respectively, light up with activity. And even the most abstract of concepts may have grounding in the real world. Body and mind This theory is called embodied cognition, and it suggests that what goes on in our minds stems from our actions and interactions with the world around us. It means that encouraging children to think and learn in a purely abstract way might actually make lessons harder for them to understand and remember.. Science is beginning to back up the idea that actions really might speak louder than words in the classroom. Spencer Kelly, a psychologist at Colgate University in Hamilton, New York, has found that people spend three times as much time gesturing when they think it is particularly important that they get a message across, suggesting that even if only at the subconscious level, we appreciate the communicative value of our body language. Kelly has also found evidence that people like a teacher better when that teacher uses arm and hand movements to emphasise points. Yet body movements can do more than simply raise a teacher’s popularity. Studies show that young children learn more if their teacher uses gestures when explaining a concept. Meanwhile, Susan Wagner Cook, a psychologist at the University of Iowa in Iowa City, has found that children pick up new concepts more effectively if they are taught to mirror and repeat the gestures their teacher uses, and that lessons involving words and gestures live longer in a student's memory than lessons using words alone. There’s a place for technology in all of this – particularly with the rise of gesture-recognition devices like the Nintendo Wii, Microsoft’s Kinect add-on for the Xbox and touchscreen tablet PCs. Researchers at the University of California, Berkeley, turned two Wii-mote video game controllers into a device that helps children visualise equivalence ratios – for instance, understanding how if one plant grows twice as fast as another, the difference between their respective heights will become larger over time. This can be a tricky concept for children to understand. When asked to use their hands to represent the different growth rates, some students will place one hand slightly higher than the other, but then raise both hands at the same speed. The Berkeley team’s device gives the children dedicated and instant feedback, helping them work out when their hand gestures correctly match what would happen as the two plants grow. Afterwards, even struggling students can articulate in words that they actually understand why moving their hands at different speeds is the correct response. The Kinect sensor, meanwhile, is being used in studies to help children learn to more accurately map numbers onto physical space – a simple skill but one that is fundamental to our understanding of mathematics. Most people know, for instance, to place the number 50 exactly midway along a line marked “0” at one end and “100” at the other. Researchers at Eberhard Karls University in Tuebingen, Germany, found that seven-year-olds can place numbers along such a line more accurately if they physically walk the line on the floor – with their motion captured and analysed by the Kinect sensor – than if they use a mouse to interact with a computer screen representation of the line. Manches has begun exploring whether Kinect offers a way to re-imagine traditional children’s blocks. The technology allows children to pick up and manipulate virtual blocks on the screen using the same gestures they would use to play with real blocks – but the virtual blocks can do new things like change colour as they are pulled apart into smaller units, giving children fresh ideas about the way numbers can be broken down. Ramp up activity? In light of all this, it’s tempting to conclude that teachers, and their students, should be jumping up and down, or waving their arms about like windmills during lessons. Manches, however, advises caution. The trouble is, science has not quite worked out exactly how the relationship between body and mind effects work. “You can’t jump into the prediction and intervention stage too early,” says Manches. This isn’t to say there aren’t working theories for what’s going on, particularly when it comes to understanding why gesturing helps lodge information more firmly in the mind, says Cook. The lessons we learn at school usually involve declarative memory – these are the facts that we can consciously recall or ‘declare’ at a later date. But some of our memories are non-declarative – things we can remember without really being able to explain why. The classic example is how we never really forget how to ride a bike. Physical movements seem to be particularly suitable fodder for making non-declarative memories, and so by both speaking and gesturing, we may encourage our brains to make two independent memories of an event, boosting our chances of remembering the event later. Even though researchers like Manches and Cook remain reluctant to set out prescriptive guidelines for teachers, their caution is beginning to weaken. “Five years ago I might have said there’s potential for real harm in giving teachers instructions from this research,” says Cook. Today, she is less worried of the potential to do damage – in part because none of her studies to-date has uncovered any evidence of detrimental side effects. “In every study that we’ve tested the importance of gesturing, we’ve found it works,” she says. “Even in the experimental settings where we thought gesturing wouldn’t work.” If you would like to comment on this, or anything else you have seen on Future, head over to our Facebook or Google+ page, or message us on Twitter.
I am working on a homework problem that presents the scenario of trying to raise water from a small reservoir of depth 8 m whose surface is 25 m below a pump that can maintain a pressure differential of 10 atm. According to the problem this is not possible, but I am charged with 1) finding the maximum height that this water could be sucked up, and 2) finding an optimal placement for the pump (instead of at the top of the hill) so that it could suck the water up. I am not given how much water is in the reservoir. I do not know where to begin. I do not really understand how the pump works (the instructor has said it does not really matter, all you need to know is that it is a "black box" that maintains this pressure differential). I would appreciate some guidance on where to begin or how to set up my equations. There's a big difference between trying to such water up from the top, and trying to push it up from the bottom. It we first consider trying to push up water from the bottom, then the height you can raise the water simply depends on how much pressure you can produce. A quick Google will tell you that a pressure of 1 atmosphere corresponds to a height (or depth) of about ten metres. So if your pump can produce a pressure of ten atomspheres it will be able to pump the water to about 100 metres. I say "about" because your professor probably expects you to calculate this exactly and I won't spoil their fun by just giving you the answer :-) The reason why sucking water up is different is because water boils at reduced pressure. The pressure at the surface of the pool is obviously one atmosphere. To suck water up you have to reduce the pressure at the pump. However if you reduce the pressure too much the water starts to boil and the water won't go up any further. All you do is suck steam. The maximum height you can suck water can be calculated from it's vapour pressure and density. When the pressure has reduced to less that the water vapour pressure the water starts to boil. Again, I won't spoil your professor's fun by just giving you the answer. This should give you some clues about how to approach the problem. If you need any more info please comment.
Bullying Prevention Starts with Adults Policies, procedures, and protocols for bullying prevention and intervention are now a requirement for most schools across the country. Yet policies that are developed and implemented in isolation are insufficient to address the challenges of bullying behavior. It is also critical to create a school culture and climate of communication, collaboration, and trust where children and adults feel safe and supported to speak up about bullying. Building a safe environment is a key element to preventing and addressing bullying in schools. New research from ChildTrends found that bullying prevention programs that use a whole-school approach to foster a safe and caring school climate – by training all adults to model and reinforce positive behavior and anti-bullying messages – were generally found to be effective. The Open Circle Curriculum, an evidence-based social and emotional learning program, focuses on both proactively developing children’s social and emotional skills (like calming down, speaking up, and problem solving) and building a school community where children and adults feel safe, cared for and engaged in learning. We encourage a unique whole-school approach that includes training all adults in the school community – teachers, administrators, counselors, support staff, and families – to learn, model, and reinforce pro-social skills throughout the school day and at home. Students are always watching. They are watching adults at their best and they are particularly watching adults when they are in conflict. While emphasis and expectations of behavior is often placed on the students, adults in schools should remember to take a step back and look at themselves, their relationships, and the behaviors students see them model. It’s imperative that adult communities in schools reflect the same expectations of behavior that we have for students. Otherwise a climate may develop where students and adults may not feel safe to identify, report, and effectively address bullying behavior. When a consistent culture and climate is created both on the student and the adult level, bullying prevention efforts will be strengthened along with creating the best possible environment for learning. Nancy MacKay, B.A., and Nova Biro, M.B.A. are Co-directors of Open Circle, a leading provider of evidence-based curriculum and professional development for social and emotional learning (SEL) in Kindergarten through Grade 5. Open Circle, a program of the Wellesley Centers for Women at Wellesley College, is at the end of its 25th anniversary year.
Four Methods for Doing Gematria Absolute value, (in Hebrew: mispar hechrachi) also known as Normative value: Each letter is given the value of its accepted numerical equivalent alef (the first letter) equals 1, beit (the second letter) equals 2, and so on. The tenth letter, yud is numerically equivalent to 10, and successive letters equal 20, 30, 40, and so on. The letter kuf near the end of the alphabet, equals 100; and the last letter, tav equals 400. In this reckoning, the letters chaf sofiet (final chaf), mem sofiet, nun sofiet, pei sofiet, and tzadik sofiet which are the "final forms" of the letters chaf, mem, nun, pei,and tzadik, used when these letters conclude a word, generally are given the same numerical equivalent of the standard form of the letter. However, sometimes the final chaf is considered equivalent to 500, the final mem to 600, etc. (see chart below). Following that alternate form of reckoning, the Hebrew alphabet is a complete cycle. The final tzadik equals 900 and thus, the alef equals both one and one thousand. Indeed, in Hebrew the same spelling is used for the name of the letter alef, and elef, meaning "one thousand." Noting this phenomenon, Rabbi Avraham Abulafia interprets the verse (Deuteronomy 32:30): "How can one pursue one thousand!" to mean: One, the first number, follows after one thousand in a complete and perfect cycle. Ordinal value (in Hebrew: mispar siduri): Each of the 22 letters is given an equivalent from one to twenty-two. For example, alef equals 1, kaf equals 11, taf = 22. The final kaf equals 23, and final tzadik equal 27. Reduced value (in Hebrew: mispar katan, modulus 9 in mathematical terminology): Each letter is reduced to a figure of one digit. For example, in this reckoning, alef equals 1, yud equals 10, kuf equals 100) would all have a numerical value of 1; beit equals 2, kaf equals 20, and reish equals 200 would all have a numerical value of 2, and so on. Thus, the letters have only nine equivalents, rather than twenty-two. In both the Ordinal and Reduced reckonings, the five letters whose form changes when they conclude a word are generally equivalent to their value when they appear within a word. However, they are sometimes given an independent value. For example, the ordinal value of the final nun is at times considered 14, and is at times, 25. Similarly, its reduced value is at times 5, and at other times, 7. Integral Reduced Value (in Hebrew, mispar katan mispari): In this fourth method, the total numerical value of a word is reduced to one digit. Should the sum of these numbers exceed 9, the integer values of the total are repeatedly added to each other to produce a single-digit figure. The same value will be arrived at regardless of whether it is the absolute values, the ordinal values, or the reduced values that are being counted.
Freedom of information Freedom of information is the right to freedom of expression on the Internet and other information technology. Freedom of information is the ability to access the Web without censorship or restrictions. Freedom of information is a human right recognised in international law. Freedom of speech includes not only the text and pictures but also the means of expression. Freedom of information may also refer to the right to privacy in the context of the Internet and information technology. The right to privacy is a human right and freedom of information is an extension of this right. References[change | change source] - Andrew Puddephatt, Freedom of Expression, The essentials of Human Rights, Hodder Arnold, 2005, pg.128 - Protecting Free Expression Online with Freenet - Internet Computing, IEEE
Watching this resources will notify you when proposed changes or new versions are created so you can keep track of improvements that have been made. Favoriting this resource allows you to save it in the “My Resources” tab of your account. There, you can easily access this resource later when you’re ready to customize it or assign it to your students. A preparation outline is a precursor to your speech outline. As its name suggests, a preparation outline helps you prepare your speech. Presentations that require significant research, visual aids, or other type of content outside of speech rehearsal usually require organization and preparation in the form of an outline. An outline is a list of items organized according to a consistent principle. Each item may be divided into additional sub-items or sub-points. A preparation outline consists of three main sections, which includes the introduction, body, and conclusion. It also includes the title of the speech. The types of preparation outlines for speeches vary. However, it is up to you to evaluate the style most appropriate for the speech, as well as the best form to assist you. Common outline styles include sentence outlines, topics outlines, chronological outlines, and alphanumeric outlines. While sentence outlines follow a hierarchical structure composed of sentences and headings around the subject of the speech, topics outlines are comprised of topics and subtopics. Alphanumeric outlines include a prefix in the form of a roman numeral at the top level, upper-case letters for the next level, arabic numerals for the third level, and lowercase letter for the final level. If, for example, you have separate visual aids for the introduction, main points in the body of your speech, and your conclusion, than using a sentence style for your preparation outline may be more appropriate. Your preparation outline will start with the introduction, along with a list of the points you would like to cover before launching into the body of your speech. This may include a preview of the main topic, an attention-grabbing quote or statistic to support the main argument of your presentation. The body of your speech will contain the details and descriptors to support the main point, topic, or argument of the speech. Here you will state each of the main points or topics you covered in your introduction, followed by supporting facts and details. Sub-topics should be added underneath each main topic covered in the body of the preparation outline No matter what type of speech you are giving, every preparation outline should have a conclusion. The conclusion allows you to re-state and emphasize your main topic or argument (mentioned in the introduction) in a summary or list of key points. Moreover, you should identify how you will end your speech for the audience. Additional items you can add to the preparation outline include references or a "works cited" list including sources you have used to prepare your speech. Remember, an outline is simply your guide. While there are traditional and non-traditional ways of outlining, do not get caught up worrying about "right and wrong" ways to outline. However, a standard preparation outline can serve as a helpful aid for a well-prepared and organized presentation. Want access to quizzes, flashcards, highlights, and more? Access the full feature set for this content in a self-guided course!
Least Tern (Threatened), Black Tern (Endangered), Roseate Tern (Endangered) and Common Tern (Threatened). Despite being the most widespread and abundant of the tern species in NYS, Common Terns have suffered significant declines in populations primarily due to increased human use of beaches for recreation, predation and competition with both Great Black-backed and Herring Gulls. During the late 19th century their populations were decimated by the millinery trade. Common Terns primarily winter along the coasts of Central and South America as far south as Peru and Argentina with small numbers along the Gulf Coast from central Texas to western Florida. One of the more unusual local breeding colonies is on a disused section of the Yankee Pier on Governor's Island in Buttermilk Channel.
Hiding among the craters in a pockmarked Martian plain lie supervolcanoes that were so powerful that their explosions left deep scars in the ground, scientists say. The first supervolcanoes ever found on Mars, described online Wednesday in the journal Nature, could go a long way to explaining the Red Planet’s mysterious internal and atmospheric history. While cold and dead today, Mars was once a hotbed of volcanic activity – and yet, we know very little about this aspect of its early evolution, said lead author Joseph Michalski, a planetary geologist at the Planetary Science Institute in Tucson. “Vulcanism is a thread which is woven through every aspect of Martian geology,” Michalski said. “So this is clearly important for understanding heat flow [and] origins of the atmosphere because the atmosphere is formed through outgassing of volcanoes.” Volcanic remains also made their way into sedimentary rocks, Michalski said. Such layered rocks make up Mt. Sharp in the middle of Gale Crater, where NASA’s rover Curiosity is headed to search for signs of life-friendly environments. But even though volcanoes clearly played a major role in Martian history, scientists simply don’t see enough dead volcanoes to explain all of the deposits built into the planet's surface. "In fact, 70% of the crust was resurfaced by basaltic volcanism, with a significant fraction emplaced from as yet unrecognized sources," the study authors wrote. So where did it all come from? Michalski said he may have chanced upon the answer. He was studying a densely cratered area in the north of Mars called Arabia Terra when he noticed a particular depression called Eden Patera that stood out from the rest. Or rather, it stood in -- at 1.1 miles deep, it was far deeper than a crater made by an asteroid slamming into the surface. An impact crater tends to erode over time, becoming shallower. Eden also lacked the other defining features of such craters, including a ring of ejected debris, a high ridge surrounding the basin and a mound in the middle. Michalski teamed up with vulcanologist Jacob Bleacher of NASA’s Goddard Space Flight Center to study Eden and two other suspect craters. They concluded that these were the remains of supervolcanoes that could have exploded and put billions of tons of volcanic ash into the air, transforming the environment. Such a volcano, like one from the quiescent supervolcano in Yellowstone National Park, would be thousands of times more powerful than the dramatic 1980 eruption of Mt. St. Helens in Washington. And this is the kind they think is made by Eden, which is roughly 43 miles wide. These eruptions are so massive that once the magma chamber empties, the volcano collapses, leaving a crater-like depression called a caldera. This could explain why no one has found these supervolcanoes before: They don't look like shield volcanoes such as Olympus Mons, Mars' roughly 13-mile-high monster and the second tallest mountain in the solar system. Shield volcanoes, the most common kind found on Mars, are created as lava pours out in layers over time, forming a flattened peak. But in explosive volcanoes formed over a hot spot of magma, the gases trapped in rising magma create bubbles that explode to the surface, hurling volcanic ash into the air. “It’s sort of like getting the bends,” Michalski said, referring to the sickness that divers can face when swimming back up to the surface too fast. “When you get the bends it’s because there’s gas dissolved in your blood and as you come up too quickly, the blood bubbles out of the gas, and that can kill you. So you've got to come up slowly. Magma does the same thing.” The magma would have been basaltic, which usually isn’t as explosive, Michalski said. But because of Mars' lower gravity, perhaps even basaltic magmas could have gone off with a bang. These supervolcanoes probably erupted some time within the first billion years of Mars’ life, Michalski said. It’s possible that the explosive supervolcanoes only existed early in Mars’ history when the magma was still full of gas and could bubble up ferociously. As that gas escaped into the atmosphere, the rest of the magma would have poured out sluggishly to create shield volcanoes, like soda that has lost its fizz. Either way, Arabia Terra might have been a good spot for supervolcanoes because the crust there is strangely thin, making it a good spot for magma to seep through, Michalski said. Eden Patera was the clearest case of the three that the duo studied, he said, but the researchers are looking to find more calderas hiding in plain sight. The findings provide a crucial link between what we see on Mars today and how it got there in the first place, Michalski added. “It’s our hope that this discovery will help to open the Pandora’s box on that kind of evaluation of the early volcanic history,” he said.
WHY REFORM THE GREGORIAN CALENDAR - The day of the week of a date is not fixed. It shifts from year to 1 this year may be Monday. Next year, it may be Tuesday. The same is true with a person's birthday. - The date of a day is not fixed. It changes from year to year. Example: Start of school term is last Monday of January. This year, it may fall on January 30. Next year, it may be on January 29. - The calendar's divisions of months, quarters and half-years are less uniform and have greater differences. The number of days varies from 28 to 31 in a month, 90 to 92 in a quarter, and 181 to 184 in a half-year. These inconsistencies in the length of the periods cause many difficulties in statistics and economic planning. - Christmas Day is celebrated on the wrong date. - Easter, a movable feast celebrating the resurrection of Jesus, wanders to different dates in March and April because it is based on the full moon around vernal equinox (March 21). Comparing these months with each other and with the corresponding months in previous year is - To the superstitious, the 13th can fall on a Friday which maybe declared unlucky. This occurs at least once every year. The maximum number of Friday the 13th is three occurring in February, March and November in a common year, and in January, April and October in a leap - To look up dates, a calendar every year or a calendar table is CALENDAR WEBPAGES: Home | Table of contents | The Calendar | Features | Signs | Why reform | Change for the better | Australia | Comparison with Gregorian | Proposed reforms | Find day | Find date | Holydays | Christian events | Reform at UN | Australian Parliament | Australian media | Academic evaluation | Excerpts | NSW holidays | Implementation | Proclamation
In order to infect a healthy cell, a flu virus must enter the cell (upper left) and empty viral genes into it. First, the virus binds to the cell. Then it becomes enveloped inside a bubble called an endosome as it gets taken into the cell. It is acidic inside the endosome--more acidic than the interior of the virus it contains. This pH difference serves as a signal to the virus that it is inside the cell, so it is time to release the viral genes (shown as orange squiggles). It is the M2 proton channel that helps the virus sense this difference in acidity and trigger the release of viral genes into the cell. Since the cell cannot tell the difference between its own genes and those of the virus, it gets tricked into making copies of the virus which can eventually go on to infect other cells. Credit: Nicolle Rager Fuller, National Science Foundation Download the high-resolution JPG version of the image. (244 KB) Use your mouse to right-click (Mac users may need to Ctrl-click) the link above and choose the option that will save the file or target to your computer. This video explains how a virus infects a cell, and illustrates how a recent finding has influenced our understanding of the viral life cycle. The discovery, that a specific molecule within the virus acts as a trigger to facilitate viral infection, provides a new target for researchers working to fight the flu.
Our senses of sight and hearing work closely together, says a new study. In the study of how one sense can affect another, Ladan Shams, a UCLA associate professor of psychology and her colleagues showed 63 participants a large number of dots on a screen in two separate phases, with a break between the phases. In one phase, the dots moved around randomly; in the other, some of the dots moved together from right to left. In both phases, the dots were accompanied by sound. Participants were divided into three groups. One group heard sound moving from right to left as the dots moved from right to left, and they heard sound that remained stationary during the random phase. A second group heard the right-to-left sound during both phases. And a third group heard sound moving in the opposite direction - from left to right - during both phases. Then, each participant experienced trials in all three conditions. As Shams expected, the participants were best able to identify the phase in which the dots moved horizontally when the sound moved in the same direction as the dots but remained stationary during the random phase. The researchers found that the sound that moved in the opposite direction neither enhanced nor worsened the participants' visual perception. Surprisingly, the sound that travelled leftward both when the dots moved leftward and when the dots moved randomly - that is, sound that provided no useful information for choosing between the two phases - also helped people correctly choose the phase with the horizontal motion. "This study shows that at least in regards to perception of moving objects, hearing and sight are deeply intertwined, to the degree that even when sound is completely irrelevant to the task, it still influences the way we see the world," said Shams, senior author of the study. The study appeared in the December issue of Psychological Science, a journal published by the Association for Psychological Science.
Happy Fun Science FRIEDay! While Ebola wreaks havoc on Homo sapiens in the terrestrial world, there has been an even more virulent disease causing the destruction of a marine animal, the sea star. Today we talk about this deadly condition impacting sea star populations and the recent discovery of just what is causing this affliction. Sea stars, also commonly known as starfish, are star-shaped echinoderms that typically have a central disc and five arms. Sea stars are generally considered to be keystone species in their respective habitats given their unique life history traits (size, diets, adaptability). In fact, Robert Paine first used the term “keystone species” in 1966 to describe the sea star, Pisaster ochraceus. Last year, a mysterious disease began appearing in sea stars in the Pacific. From Alaska to Mexico, sea stars from 20 different species were contracting an unknown disease, and the death toll was in the millions. This mystery disease was extremely deadly, condemning nearly 100% of sea stars that contracted the disease to a horrific death. Known as sea star wasting disease, an infected sea star would undergo rapid degradation (fancy science speak for melting). In the end, all that would be left of the infected sea star would be a pile of slime and a few pieces of invertebrate skeleton. Despite the magnitude of the calamity scientist were perplexed at what was causing the disease, that is until a team of American and Canadian scientists, led by Ian Hewson of Cornell University, recently revealed the culprit to be a virus. Ian and his team were unsure if a bacteria, virus, or parasite caused sea star wasting disease, but after examining hundreds of slides of infected sea star tissue, they surmised the disease was likely caused by a virus. They then devised an experiment to affirm their suspicions. They injected healthy sea stars with the liquefied tissue of infected sea stars, and also injected a control group of sea stars with the same liquefied tissue, except they sterilized the tissue to kill any pathogens. Sure enough, a week after being injected with the non-sterilized tissue, healthy sea stars began exhibiting sea star wasting disease and eventually experienced mortality. Going a step further to identify the virus, Ian and his team then genetically sequenced and sorted the infected sea stars’ tissue. Those analyses yielded a genome of a previously unknown virus, which the researchers named sea star-associated densovirus. This virus is similar to diseases known to infect insects and also has genetic similarities to a disease that occasionally infects Hawaiian sea urchins. Now that the virus impacting these sea stars has been identified, questions still remain about the origin, and what is next for sea stars in the wild still battling this pathogen. You can read more about this interesting study that Ian et al. published in the Proceedings of the National Academy of Sciences.
WHY WERE SO MANY BATTLES FOUGHT AT PANIPATH ?(2020) In Indian history, Panipath is well known as a battlefield as there were many battle fought. It is located in Haryana state and along the banks of Yamuna river. There are many reasons behind the question “Why were so many battles fought at Panipath. Some main reasons explained below-: 1.During the Sultanate period, Panipath was made the city where messengers for officials from the other states or countries who wished to meet the Sultan of Delhi, used to stay at Panipath during their visit. A Councilor was appointed at that area who give formal permissions and scheduled appointments at the medieval times. 2.Long ago, Panipath was like the entrance of Delhi for the visitors like Afghans and Persians. As well as it is also the entrance gate for the invaders who came from the Northern countries to attack and spread their kingdom over here. 3.The availability of most essential things that needed at the time of War was here; like proper suitable climate, Food and water etc. These things leads the attackers to fight here with such of avail things for their soldiers. It was a place where the soldiers from both sides find food and water to survive the battle. 4.From the military point of view there are other technical consideration like tactics of defense, attack, advance, envelopment, tactical retreats etc. also available here. So, War in this place is quite acceptable. 5. Panipath is a vast plain ground area where it is convenient to fight a great war with large number of artillery(heavy guns that are moved on wheels),cavalry(army that were fought on horse) and infantry(soldiers who fought on foot).It is also acceptable that as Panipath is a plain area, so the amount of loss of property of kingdom was lower here, that might be property loss or people loss. MAJOR WARS AT/NEAR PANIPATH 1.According to Indian Mythology, The Kurukshetra war of Mahabharat was fought on the land of Kurukshetra which is 73 km away from Panipath. This war was fought here to reduce the loss of people and property of the kingdom. 2.The Battle of Thanesar which was fought in 1567 AD was 78 km away from Panipath in which the result was the expulsion of two rival groups of Sanyasis from the encampment of the Mughal Emperor Akbar. 3.The Battle of Tarrain which was fought in between Prithviraj Chauhan and Muhammad Ghori was also 86 km away from Panipath in 1191 and 1192 AD.
These are some common tools used to work on this device. You might not need every tool for every procedure. A refrigerator (often called a fridge) is a household appliance that includes a thermally insulated compartment and a heat pump. The pump, which can be mechanical, electronic, or chemical, transfers heat from the inside of the refrigerator to its outside environment. This keeps the inside of the appliance cooler than the area outside. In many countries, refrigeration is considered an essential food storage technique. The ideal temperature for storing perishable food in refrigerators is between 3 and 5 degrees Celcius (or between 37 and 41 degrees Fahrenheit), which is just above the freezing temperature of water. These cooler temperatures lower the reproduction rate of bacteria so food takes longer to spoil. Similarly, freezers maintain foods at a temperature below the freezing point of water. Freezing foods can halt the reproduction of bacteria entirely. Refrigerators replaced the icebox, which was common in households for approximately 150 years. The development of the first artificial refrigeration systems began in the mid-1750s. The first working refrigeration system using vapor compression was built in 1834. Early systems for cooling food mainly involved the use of ice. However, a vapor-compression refrigeration system was introduced in 1834. Modern refrigerators were invented for household use in 1913. Frigidaire sold the first self-contained refrigeration unit in 1923. Freezers as separate compartments for refrigeration systems were introduced in 1940. The most common means of identifying your fridge is to classify it by type as listed below, and then look for a manufacturer's label on it. Model numbers from the label are critical to identification for exact parts matching and also for determining what features are provided on the unit. - Traditional style - Freezer on top, Fridge on bottom - Side-by-side style - Fridge one side (usually right), Freezer on the other - Top-refrigerator/bottom-freezer style - French-door style - Double-door (saloon style) Fridge up top, Freezer drawer on bottom - Four-door French-door style - Double-door (saloon style) Fridge up top - Either two drawers OR saloon style double-doors down below - Door and drawer - As far as I can tell, same as "French-door"
Wetlands are crucial ecosystems that provide a wide range of environmental, social and economic benefits yet they often go unnoticed and are undervalued. These waterlogged areas, which can include marshes, swamps and bogs, are critical habitats for countless plant and animal species. Prof Raphael Kapiyo, an environmental scientist at Maseno University, explains that wetlands are among the most productive ecosystems on the planet, playing a vital role in mitigating climate change. According to Prof Kapiyo, wetlands act as natural sponges, absorbing and filtering excess nutrients, pollutants and sediments from water bodies, which help to purify water and prevent flooding. Furthermore, wetlands are essential for biodiversity conservation. They provide critical habitat for migratory birds, fish and other wildlife. Wetlands are also important carbon sinks, with the ability to store large amounts of carbon in their soils and vegetation. By conserving and restoring wetlands, we can help to reduce greenhouse gas emissions and combat climate change. Despite their importance, wetlands are under threat from human activities such as agriculture, urbanisation, and resource extraction. Many wetlands are being drained or converted for other uses, which can have devastating consequences for their ecological and socio-economic functions. - First, I was told it was malaria but tests showed it was typhoid - Bliss donates drugs to mark World Malaria Day - Using technology to combat malaria - Global Fund procured mosquito nets directly from manufacturers, Kemsa maintains According to the United Nations Environment Programme, wetlands are among the world’s most productive ecosystems, providing a wide range of ecosystem services. These include flood control, water purification, biodiversity conservation, and climate regulation.
Click for a transcript of the photosynthesis video. Hi, it's Mr. Andersen, and in this podcast, I'm going to talk about photosynthesis. I love photosynthesis because it gives me two things that I need. I need to breathe, so it gives me oxygen. And I need to eat, and so, it's going to give me food. And so, I love photosynthesis. You might think it's only found in these things, plants. But it's also found in bacteria. It's found in algae, and so, it's found in protists, it is found everywhere. And so, photosynthesis has been around a long time, and it’s super important that you understand how it works. So, let's start with the site in eukaryotic cells of photosynthesis, and that's the chloroplast. So, this is a number of cells, and you can see how many chloroplasts we could have in a typical cell, so there's a whole bunch of them. There are a few terms you should be familiar with and where they are. First one is a thylakoid membrane. Thylakoid membrane is going to be organized like this, and basically, that's where the light reaction is going to take place. If you got a stack of thylakoids, like this together, we call that a granum. The other big thing to understand photosynthesis is that this is filled with a liquid, and that liquid is called the stroma. That's going to be the site of the Calvin cycle. If we were to grind up a leaf, what we would find is that there's not only one pigment, chlorophyll A, that does photosynthesis, but there's a number of them that are working together. And so, if you grind up a leaf into some chromatography paper, and then you put it in a solvent, what you'll get is chromatography. It's going to separate into all its different parts. And so, this right here would be chlorophyll A, and chlorophyll B, and this would be like carotene and xanthophylls, and they're all working together. You'll see these other pigments in the fall when the chlorophyll moves back into the leaf and is reabsorbed, but if we look at what light they absorb, here's chlorophyll A and here's B, this is what's called their absorption spectrum, what color of light they're able to absorb. And you can see that they absorb a lot of the blue, a lot of the red, but they don't absorb a lot of this in the middle, this green. And so, a question could be, what is their least favorite color, plants - and the right answer would be green because they reflect that green light. Now, this has actually puzzled scientists for a long time, and we really don't have a definitive answer as to why plants are green. Know this, that if they were black, they probably would get a little bit too hot, they would absorb too much light. And so, let's start with an equation, because this is simply a chemical reaction. It's a chemical reaction with a number of steps. But what are the reactants? Water and carbon dioxide. And so, how does a plant grow? It's basically taking water in from its roots and it's taking carbon dioxide in through its leaves, through its stomata. The other thing it needs is light. And so, it's just taking these simple ingredients, and then it's weaving those together into glucose, this monster molecule here, and then oxygen. And so, this is the food that I get and this is the oxygen that I breathe. Now, are plants just nice? No. They're making this sugar for themselves so they can break it down using cellular respiration. And in fact, if I put this arrow in the other direction, that becomes cellular respiration. So, they're making food for themselves, and they're also going to make some of the structures. So, like the cellulose in the cell walls of a plant is made from that, as well. Okay, so, whenever I try to think what are the different steps in photosynthesis, I always imagine this picture right here. There's photo and synthesis in the word. Photo means “light” and synthesis means “to make”. And so, there are two steps in photosynthesis. The light reaction and those are going to take place in the thylakoid membrane, and then the Calvin cycle. We used to call this the dark reactions, which is a silly term, doesn't happen during the dark, it happens during the light. And so, basically, the person who worked this all out is Melvin Calvin, and so, we named it after him. Where does this take place? You guessed it, it takes place in the stroma or this liquid portion. And so, let's kind of do a cartoon version of photosynthesis. What are the reactants again? Water, light, and carbon dioxide. What are going to be the products that come out of this? It's going to be oxygen and glucose. So, let's watch what happens. In the light-dependent reaction, water and light go into the thylakoid membrane, and they produce two things. They produce oxygen; oxygen is simply waste product. And then, they're going to produce these chemicals, NADPH and ATP, so they have energy now. Let's watch what happens to them. Well, the energy is going to transfer to the Calvin cycle, where carbon dioxide comes in, and then glucose goes out. And so, this is the big picture of photosynthesis. But now, let's kind of dig in a little bit deeper and talk about the light reaction. Okay, so, where are we? We’re in the thylakoid membrane, so we're in this membrane right here. So, if we were to zoom into that membrane right here, that's what this diagram is. Okay, so, what are the two things coming in? Well, the first one is going to be light. So, light's coming in here, light's coming in here. What's the next thing that we're going to have coming in? And that's going to be water. Okay, so, let's look at some of the other big features in this thylakoid membrane. So, this is the outside of the stroma, and this is going to be the lumen or the inside. And so, there's a couple of big things right here. What's in here? Well, these are basically going to be proteins with chlorophyll on the inside of it, and so, we call that whole thing together a photosystem. So, this first one is actually called photosystem 2 and then, we go to photosystem 1. And the reason we go backward is that photosystem 1 was discovered first. So, basically, what comes in? Light. What's that light used to do? Well, that light is used to power the movement of an electron through an electron transport chain. So, that electron is going through proteins, carrier proteins, and eventually that electron is going to go to here. It's going to go to NADPH because remember, that's one of the products of the light-dependent reaction. Okay, what happens to the water then? So, the water is going to be split right away. If you split water, what do you get? Well, you get oxygen, so, that's the O2 that’s going to diffuse out of a cell and that's the oxygen that you're actually breathing right now. And then, we're going to have these protons, which are simply hydrogen ions, so, they're hydrogen atoms that have lost their electron. Okay, so, this is getting kind of messy, so, let's look what happens next. As that electron moves through the electron transport chain, and again, it's powered by the introduction of light here and light here, that electron is going to be moving all the way down here. And every time it goes through one of these proteins, it's pumping protons to the inside, so it's pumping protons to the inside. Now, protons have a positive charge, so, basically, what's happening is that you're building up a positive charge on the inside, so, there's a positive charge in here. If you know how cellular respiration works, you'll realize that this is the opposite of that. So, now, we have all these positive charges on the inside. Where do they go? Well, there's only one hole that they can go through, and that is to go through this protein here. As those protons move out, they're moving through a protein called ATP synthase, and it works almost like a little rotor, and every time a proton goes through, we make another ATP. So, what have we made in the light-dependent reaction? We've made NADPH and we've made ATP. And what's nice about that is, they're now just sitting right here in the stroma and so, they're able to go on to the Calvin cycle, which is going to be the next step in this process. And so, who's providing the energy? Light. Who's providing the electrons? Water. And then, a base or a waste product to that is simply going to be oxygen. Okay, let's go to the Calvin cycle, then. So, what's happening in the Calvin cycle? You can see here's those reactants. So, we've got our ATP here, ATP here, and NADPH. What are they providing? Simply, energy. We also have this molecule here. It's called RUBP. Basically, it's a five carbon molecule. And then, we have carbon dioxide coming in. So, it moves through the stomata of the leaf and it's going to diffuse its way in. Carbon dioxide is a one carbon molecule, so, basically, there's an enzyme here called Rubisco and it's going to attach this one carbon molecule to a five carbon molecule. It immediately breaks into two, three carbon molecules and then it gets energy from ATP and NADPH. And when we're done, it's creating this chemical down here called G3P.What does G3P become? Well, it can be assembled quickly into glucose or sucrose or maltose or whatever they need to do, that's going to be produced right in here by the G3P. So, that's where we're synthesizing. In other words, we're taking carbon and we're fixing it. We're making it usable. Now, some of that G3P is released, but a lot of it is recycled again to make more of this RUBP, and so, that's why it's a cycle over and over again. What's the big picture? If we don't have ATP, if we don't have NADPH, then this process is going to shut down. What's the other thing that could shut it down? If we don't have carbon dioxide. Okay, so, that's basically photosynthesis, and again, it's been working for billions of years. But there's a slight problem, and that problem is called photorespiration. What is photorespiration? Well, photorespiration occurs only when we don't have enough carbon dioxide. So, if we don't have enough carbon dioxide (let me cross that out), well we certainly can't make our G3P, but something worse happens. Oxygen can actually jump into the Calvin cycle and using Rubisco, can form another chemical. Now, that chemical doesn't do anything. In other words, it has no purpose, and the cell actually has to break it down. And so, as a result of that, plants, and we call almost all plants C3 plants, and the reason we call them C3 plants is this G3P is going to be a three-carbon molecule. So, these C3 plants, photorespiration is bad. In other words, they don't get anything out of it. And so, they're going to lose based on that oxygen kind of jumping into the Calvin cycle. And so, you might think, evolutionarily why would this have even evolved? Well, remember photosynthesis shows up first and then oxygen in the atmosphere shows up much later, and so, it wasn't a problem initially, but it became a problem. Another question you might think is, well, when are we not going to have enough carbon dioxide? When wouldn't we have carbon dioxide? Well, how do they get carbon dioxide? A plant is going to have a stomata, and it's surrounded by guard cells. So, basically, when a plant opens up its stomata, carbon dioxide can diffuse in. And so, the only time the plant wouldn't have carbon dioxide, because we have tons of carbon dioxide in the atmosphere, is when it's actually closed. And when would it be closed in a plant? The only time it's closed is when it's really, really hot, and a plant doesn't want to lose water, because through transpiration you're constantly losing water. And so, if you're a plant, if it's a hot day, you have this really tough choice. If you open up your stomata, you're going to lose water; you could shrivel up. If you close it, you can't get carbon dioxide in, and then you're going to start doing photorespiration. And so, of course, nature has come up with solutions to this over time. And it's only going to be found in plants that live in a really hot environment. So, here's the first solution, and this totally makes sense. So, this is in CAM plants. CAM plants, an example would be a jade plant or like a pineapple. Basically, what they do is they only open their stomata at night. And so, at night, they open up their stomata, and then the carbon dioxide will come in, and they'll create malic acid out of it. So, they're going to store it in vacuoles inside the cell. Okay, so now, when it's daytime, what they can do is they can close the stomata because they don't want to lose water, and now, they can actually take that carbon dioxide out of the malic acid and they can use it in the Calvin cycle to make sugars. So, the great thing about a CAM plant is, again, they're only taking in carbon dioxide at night when it's cool. And then during the day, they can close their stomata and they don't lose water. Another example of this would be in C4 plants. What they do is, instead of doing it day and night, what they'll do is they'll take that carbon dioxide in and they'll actually use enzymes to make a four-carbon molecule out of it. That four-carbon molecule will move to some cells on the inside of the leaf, called the bundle sheath cells, and then they can simply introduce carbon dioxide into the Calvin cycle, here. And so, again, both of these solutions are basically taking in carbon dioxide when you can get it, creating a chemical out of it, and then they can introduce that chemical into the Calvin cycle, and they don't have to wait for carbon dioxide to diffuse in. Now, of course, there's going to be extra steps in here. So, it's going to require more energy and so, we only see this in areas where it's really, really, warm. But an example of a C4 plant that we all eat and use a lot of, in fact most of us are just made out of this stuff, is corn. And so, that's photosynthesis. A simple problem is photorespiration, but I hope that's helpful.
Collins Classics - Narrative of the Life of Frederick Douglass (Collins Classics) HarperCollins is proud to present its incredible range of best-loved, essential classics. You have seen how a man was made a slave; you shall see how a slave was made a man. Born into slavery during the early nineteenth century, Frederick Douglass escaped to freedom before he was twenty-one years old. From the moment he arrived in New York City, he felt a need to tell his story, one that mirrored so many people still enslaved in the South with no hope of escape. As an orator and preacher, Douglass was an abolitionist, supporter of women’s suffrage and staunch defender of equality for all. In his first autobiographical work, published in 1845, The Narrative of Frederick Douglass describes how he went from slave to a free man.
Off the baking Interstate 40 in Arizona, the evidence is clear: From time to time, sizable asteroids do pummel Earth. There, you'll find the 600-foot-deep "Meteor Crater," which landed 50,000 years ago. The culprit was likely some 100 to 170 feet across, creating a blast big enough to destroy Kansas City. While the space rock wasn't small, it wasn't nearly a "planet-killer" like the roughly six-mile-wide behemoth that wiped out most dinosaurs. Though the threat of another significant collision — whether from an asteroid 200 feet or 2,000 feet across — is inevitable, scientists have optimistic news to report. A new census of many of the largest asteroids that pass through our solar system neighborhood confirmed there's no known threat of collision for the next century, and the likelihood of an impact in the next thousand years is exceedingly low — though there are around 20 huge cosmic rocks researchers will keep tabs on, because their distant future trajectories aren't yet certain. Crucially, there's no alarm about these particular asteroids, which are a kilometer (0.6 miles) wide or even larger. But the new research underscored that a thousand years into the future some trajectories remain unsettled, and more observation is needed to completely rule out a potential impact. "We need more information about these asteroids, although the probability [for an impact] is still very low," Oscar Fuentes-Muñoz, a researcher at the University of Colorado Boulder who led the new census, told Mashable. This planetary defense research, currently posted on the research-sharing platform arxiv, will be published in The Astronomical Journal, a peer-reviewed publication. Why the threat of an asteroid collision is low NASA and other scientists are vigilantly watching the skies for "near-Earth objects," also commonly called "near-Earth asteroids." Astronomers have found nearly 10,000 nearby space rocks ("nearby" often means many millions of miles away) that span over 460 feet across, as of May 2023, with some 500 more such objects sleuthed from the dark skies each year. These have the potential to cause vast regional destruction, and an estimated 15,000 remain undiscovered. Fortunately, over 90 percent of the largest behemoths — over a half-mile across — have been found. Future impact risk remains low, however, for two reasons: The evidence we have about the frequency of asteroids that hit Earth today and in the past, along with no proof of any known looming asteroid strikes. (Asteroid-sleuthing telescopes are trained on the skies each night.) Impressively, every single day about 100 tons of dust and sand-sized particles fall through Earth's atmosphere and promptly burn up. Every year, on average, an "automobile-sized asteroid" plummets through our sky and explodes, explains NASA. Impacts by objects around 460 feet in diameter occur every 10,000 to 20,000 years, and a "dinosaur-killing" impact from a rock perhaps a half-mile across or larger happens on 100-million-year timescales. In short, the chances of a major impact in our lifetimes is, as far as we know, extremely small, astronomers say. This latest census looked at 851 giant asteroids whose orbits at times pass through Earth's neighborhood, and who spend a longer time near us. Though they pose no threat in the next century, the researchers endeavored to see what the asteroids might do farther out, in a thousand years, after they're affected by the gravity of other planets and scorching heat from the sun. They ran new simulations of the asteroids' orbits, and found most pose no threat. But some 20 asteroids, whose orbits around the sun aren't as certain, didn't prove as predictable. More observation is necessary. For example, simulations of the asteroid 7482 (1994 PC1), which is two-thirds of a mile long, showed the rock passed through Earth's orbit around the sun (though not Earth) multiple times over the next thousand years. For now, 7482 (1994 PC1)'s impact risk can't be ruled out. How scientists find nearby asteroids Sky surveys, as noted above, are regularly finding new asteroids. There's the NASA-funded Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) atop Maui, the Catalina Sky Survey in Arizona's Santa Catalina Mountains, and the Asteroid Terrestrial-impact Last Alert System (ATLAS) with telescopes around the world, among other asteroid-watching programs. The surveys can provide crucial information about a potential strike and how it would affect Earth and its denizens. For example, would people in a certain region need to shelter indoors away from glass windows if an asteroid were expected to explode in the atmosphere? (For reference, see the Chelyabinsk meteor event.) "You need to know what's coming, when it's coming, and how hard it's going to hit," Eric Christensen, the director of the NEO-seeking Catalina Sky Survey in Arizona, told Mashable last year. What's more, giant new telescopes, like the Vera C. Rubin Observatory, located over 8,700 feet up in Chile's Cerro Pachón ridge, will soon come online and take inventory of millions of solar system objects, including new rocks that at times swing near Earth. "We're doing our due diligence to completely find them." It's not easy to find new points of moving light in our crowded solar system. But scientists are identifying these potential threats. "We're doing our job," said Fuentes-Muñoz. "We're doing our due diligence to completely find them." And when we do find any that might veer toward Earth, we likely won't be helpless. The plan is to divert such an asteroid's trajectory. In an unprecedented September 2022 achievement, NASA's DART mission successfully crashed a refrigerator-sized spacecraft into the asteroid Dimorphos (which was not a threat to Earth) in an effort to prove that humanity could alter the path of an incoming space rock, should this effort become necessary. Today, we don't have the capability to readily deploy an asteroid-deflecting endeavor. But if the relentless march of technology is any hint, we might be well-equipped to deal with an imminent asteroid threat a century or so from now, if not sooner. "You expect we'll be a lot farther along," Fuentes-Muñoz said.
When the temperature at the ground surface changes, the temperature of the underlying substrate (soil, rock, or ice) will also change in response, as heat diffuses and advects vertically. For example, a sustained increase of ground surface temperature will cause a wave of warming to propagate downward. The vertical distribution of temperature below the surface thus contains information about past temperatures at the surface (Lachenbruch and Marshall 1986, Paterson 1994). Temperature-depth profiles of this sort are measured in boreholes, and analyses of these data can be used to generate reconstructions of near-surface air temperature (Lachenbruch and Marshall 1986, Huang et al. 2000, Pollack and Huang 2000, Harris and Chapman 2001, Pollack and Smerdon 2004, Majorowicz et al. 2006), provided that the ground surface temperature and the climatic temperature at the borehole site are closely connected. BOREHOLES IN ROCK AND PERMAFROST Analyses of a large number of continental boreholes have yielded temperature reconstructions for the last 500 years (Lachenbruch and Marshall 1986, Pollack and Huang 2000, Harris and Chapman 2001, Majorowicz et al. 2006). These reconstructions have particular value because they do not have to be calibrated against the instrumental record and because temperature itself is being measured, not a proxy for temperature. Important quantitative uncertainties exist, but general trends in these reconstructions are likely robust. Borehole-based temperature reconstructions averaged for broad regions (including eastern North America, western North America, Europe, Australia, and South Africa) show warming from the 19th century to the present and persistently cool conditions for the preceding few centuries (Gosnold et al. 1997, Pollack and Huang 2000 and references therein, Huang et al. 2000, Harris and Chapman 2001, Pollack and Smerdon 2004, Majorowicz et al. 2006). Temperature changes for earlier times are not resolvable. Estimates of the magnitude of recent warming as a global (continental) average, or an average over the middle latitudes, are approximately 0.7–0.9°C, from the mid-19th century to the late 20th century (Huang et al. 2000, Pollack and Huang 2000, Harris and Chapman 2001), which is similar to the temperature increase estimated from the instrumental record discussed in Chapter 2 (Figures 8-1 and 8-2). Some borehole-based reconstructions also indicate an earlier persistent smaller warming of roughly 0.3°C from 1500 to 1850 (Pollack and Huang 2000, Huang et al. 2000) (Figure 8-1). Regional estimates for the warming of the last 150 years range from 2–4°C for northern Alaska (Lachenbruch and Marshall 1986, Pollack and Huang 2000) to 0.5°C for Australia (Pollack and Huang 2000). Estimates for the western and eastern sectors of North America are rather different, 0.4–0.6°C and 1.0–1.3°C, respectively (Pollack and Huang 2000). LIMITS ON BOREHOLE-BASED RECONSTRUCTIONS The time resolution and length of borehole-based surface temperature reconstructions are severely limited by the physics of the heat transfer process (Clow 1992). A surface temperature signal is irrecoverably smeared as it is transferred to depth. The time resolution of the reconstruction thus decreases backward in time. For rock and permafrost boreholes, this resolution is a few decades at the start of the 20th century and a few centuries at 1500. Borehole temperatures thus only reveal long-term temperature averages and trends prior to the period of instrumental records; they tell us nothing about decadal variations or specific years, except for the most recent ones. For rock and permafrost boreholes, the thermal smearing is strong enough to prevent recovery of clear temperature signals prior to about 1500. The spatial distribution of borehole temperature records is also strongly weighted toward North America, Europe, South Africa, East Asia, and Australia (Pollack and Smerdon 2004), with almost no information from South America and North or Central Africa and spotty coverage in Asia. Furthermore, the usable boreholes are mostly a legacy of mining exploration, so the spatial coverage has not been chosen to optimize climate reconstruction. Important quantitative uncertainties in borehole-based reconstructions could arise from two separate sources. First, borehole temperatures respond to the ground surface temperature and not the temperature in the overlying air (Gosnold et al. 1997, Smerdon et al. 2004, Pollack et al. 2005). It is possible that these two temperatures will vary differently over time, for example, due to changes in snow cover and soil moisture. Thus, a key question is whether long-term trends in air and ground temperature are similar. Although there are clear exceptions (Gosnold et al. 1997), the majority of evidence indicates that this similarity is generally strong: As a large-scale geographic average, measured ground temperatures match those predicted directly from air temperature changes (Harris and Chapman 2001), and air versus ground temperature trends are similar at some specific sites (Baker and Ruschy 1993, Majorowicz and Safanda 2005, Majorowicz et al. 2006). The second important potential source of error in rock borehole-based temperature reconstructions is the downward percolation of groundwater, which can reduce the temperature at depth and be misinterpreted as a warming of the surface over time (Chisholm and Chapman 1992, Harris and Chapman 1995, Ferguson and Woodbury 2005, Majorowicz et al. 2006). This may introduce a “warming” bias to reconstructions based on continental boreholes, the magnitude of which has not been addressed systematically. However, the similarity between measured ground temperatures and ground temperatures calculated using air temperatures (Harris and Chapman 2001) suggests that the average bias must be small over the middle latitudes. In general, groundwater bias can only be a problem in humid climates and in rock that readily conducts groundwater (including all highly fractured rock and many sandstones and basalts). The groundwater bias cannot be responsible for the strong reconstructed warming in permafrost regions of northern Alaska (Lachenbruch and Marshall 1986) and in the semiarid U.S. and Canadian plains (Gosnold et al. 1997), although it may be partly responsible for the stronger reconstructed warming in eastern versus western North America (Pollack and Huang 2000). A comparison of borehole-based and instrumental 20th century warming trends for specific regions (Pollack and Smerdon 2004) shows no consistent offset related to precipitation: borehole-inferred warming exceeds instrumental warming in the wet regions of North America but is less than instrumental warming in the wet regions of Europe and Southeast Asia. This is further evidence that the groundwater bias is quantitatively small in borehole-based temperature reconstructions on larger scales. The borehole temperature database has been screened to eliminate other sorts of groundwater influences that are more readily apparent (Huang and Pollack 1998). A separate issue from the uncertainty of reconstructions is that air temperature itself can change for many local reasons, including deforestation and urban expansion (Skinner and Majorowicz 1999, Majorowicz et al. 2006), as discussed in Chapter 2. Borehole temperatures do record such changes, which are real changes of local climate. The borehole temperature database has been screened to eliminate sites with urban influence. Effects of rural land use change are not eliminated and represent part of the human influence on climate in rural regions. BOREHOLES IN GLACIAL ICE A small number of boreholes in the ice sheets have also been analyzed in conjunction with ice core studies (Cuffey et al. 1994, 1995; Cuffey and Clow 1997; Dahl-Jensen et al. 1998, 1999). Ice sheet boreholes permit longer timescale temperature reconstructions because of the purity of ice, the great depth of the boreholes, and the opportunity for combination with isotopic information from the ice core itself. These analyses can only be conducted in dry cold ice, and so are limited to the polar ice sheets and some high-altitude sites. As with the continental boreholes, the time resolution of reconstructions is strongly limited by the heat flow process; ice boreholes can only be used to reconstruct long-term averaged temperatures. Ice borehole reconstructions have used several different methods, yielding similar results (Cuffey et al. 1995, Dahl-Jensen et al. 1998, Clow and Waddington 1999). The main assumption of these analyses is that the physical process of heat transfer in the ice is well understood. As with continental boreholes, the ice boreholes give a temperature history that is the local surface temperature. For central Greenland (Cuffey et al. 1995, Cuffey and Clow 1997, Dahl-Jensen et al. 1998), results show a warming over the last 150 years of approximately 1°C ± 0.2°C preceded by a few centuries of cool conditions. Preceding this was a warm period centered around A.D. 1000, which was warmer than the late 20th century by approximately 1°C. An analysis for south-central Greenland (Dahl-Jensen et al. 1998) shows the same pattern of warming and cooling but with larger magnitude changes. Uncertainties on these earlier numbers are a few tenths of a degree Celsius for averages over a few centuries. A borehole from Law Dome (Dahl-Jensen et al. 1999), in coastal East Antarctica, reveals a warming of approximately 0.7°C from the middle 19th century to present (uncertainty of approximately 0.2°C). This was preceded by a period of comparable warmth centered on 1500–1600, a 1°C cooler period centered on 1300, and consistently warmer conditions prior to this (with temperature at A.D. 1 being approximately 1°C warmer than the late 20th century). There was no apparent warming during medieval times at this site. Uncertainties on these results for earlier time periods are on the order of a few tenths of a degree Celsius for averages over a few centuries.
The international Zoonomia Project has analyzed the genomes of 240 mammalian species, revealing conserved regions that could be biologically essential and may influence diseases. It suggests 10% of the human genome is functional, extending beyond protein-coding areas. The research has uncovered genetic traits related to human diseases and unique mammalian features, and has provided insights into evolutionary events and species diversity. From the two-gram bumblebee bat to whales weighing many tons, the more than 6,000 species of mammal on the planet – including humans – are highly divergent. Over the past 100 million years, they have adapted to nearly every environment on Earth. Now, an international collaboration of scientists with the Zoonomia Project – the largest comparative mammalian genomics resource in the world – has cataloged the diversity in the genomes of 240 mammalian species, representing over 80% of mammalian families. Their findings across 11 papers in this issue of Science pinpoint parts of the human genome that have remained unchanged after millions of years of evolution, providing information that may shed light on human health and disease. The authors’ work also reveals how certain uncommon mammalian traits – like the ability to hibernate – came to be. They say these analyses — and the breadth of questions they answer — only show a fraction of what is possible with this data for understanding both genome evolution and human disease. The Zoonomia Project is an international effort in which researchers sequenced a range of mammal genomes and then aligned them – a massive computational task. Using the alignment, the researchers identified regions of the genomes, sometimes just single letters of DNA, that are most conserved, or unchanged, across mammalian species and millions of years of evolution — regions that they hypothesized were biologically important. These regions – while they don’t give rise to proteins – may contain instructions that direct where, when, and how much protein is produced. Mutations in these regions could play an important role in the origin of diseases or in the distinctive features of mammal species, the authors hypothesized. Through their analyses, the researchers tested this hypothesis and were also able to ascertain that at least 10% of the human genome is functional, ten times as much as the approximately one per cent that codes for proteins. The findings further revealed genetic variants likely to play causal roles in rare and common human diseases, including cancer. In one paper in the package, researchers studying patients with medulloblastoma identified mutations in evolutionarily conserved positions of the human genome they believe could be causing brain tumors to grow faster or to resist treatment. The results show how using this data and approach in disease studies could make it easier to find genetic changes that increase disease risk. In other papers in the package, the researchers pinpointed parts of the genome linked to a few exceptional traits in the mammalian world, such as extraordinary brain size, superior sense of smell, and the ability to hibernate during the winter. The authors use the genomes to confirm that estimate of effective population size and diversity can help predict risk in species that are hard to monitor and sample. Another study in the package shows that mammals had begun to change and diverge even before the Earth was hit by the asteroid that killed the dinosaurs, approximately 65 million years ago. A different study examined more than 10,000 genetic deletions specific to humans using both Zoonomia data and experimental analysis and linked some of them to the function of neurons. Other Zoonomia papers in the package uncovered a genetic explanation for why a famous sled dog from the 1920s named Balto was able to survive the harsh landscape of Alaska; discovered human-specific changes to genome organization; used machine learning to identify regions of the genome associated with brain size; described the evolution of regulatory sequences in the human genome; focused on sequences of DNA that move around the genome; discovered that species with smaller populations historically are at higher risk of extinction today; and compared genes between nearly 500 species of mammals. The special issue is accompanied by two Perspectives that provide further insights into the Zoonomia Project’s approach, findings, and future impacts. Zoonomia Special Issue Science – DOI: 10.1126/science.adi1599 - “Zoonomia” by Sacha Vignieri (MS# adi1599) - “Genomics expands the mammalverse” by Nathan S. Upham & Michael J. Landis (MS# add2209) - “Seeing humans through an evolutionary lens” by Irene Gallego Romero (MS# adh0745) - “Mammalian evolution of human cis-regulatory elements and transcription factor binding sites” by Gregory Andrews et al. (MS# abn7930) - “Comparative genomics of Balto, a famous historic dog, captures lost diversity of 1920s sled dogs” by Katherine L. Moon et al. (MS# abn5887) - “Relating enhancer genetic variation across mammals to complex phenotypes using machine learning” by Irene M. Kaplow et al. (MS# abm7993) - “A genomic time scale for placental mammal evolution” by Nicole M. Foley et al. (MS# abl8189) - “Evolutionary constraint and innovation across hundreds of placental mammals” by Matthew J. Christmas et al. (MS# abn3943) - “Leveraging base-pair mammalian constraint to understand genetic variation and human disease” by Patrick F. Sullivan et al. (MS# abn2937) - “Integrating gene annotation with orthology inference at scale” by Bogdan M. Kirilenko et al. (MS# abn3107) - “The functional and evolutionary impacts of human-specific deletions in conserved elements” by James R. Xue et al. (MS# abn2253) - “Three-dimensional genome rewiring in loci with human accelerated regions” by Kathleen C. Keough et al. (MS# abm1696) - “Insights into mammalian TE diversity through the curation of 248 mammalian genome assemblies” by Austin B. Osmanski et al. (MS# abn1430) - “The contribution of historical processes to contemporary extinction risk in placental mammals” by Aryn P. Wilder et al. (MS# abn5856) Be the first to comment on "Zoonomia Project: A Genomic Odyssey Across 240 Mammalian Species Explains Human Disease Risks and More"
Stage of the English language from about the 12th through 15th centuries / From Wikipedia, the free encyclopedia Dear Wikiwand AI, let's keep it short by simply answering these key questions: Can you list the top facts and stats about Middle English? Summarize this article for a 10 years old Middle English (abbreviated to ME) is a form of the English language that was spoken after the Norman Conquest of 1066, until the late 15th century. The English language underwent distinct variations and developments following the Old English period. Scholarly opinion varies, but the Oxford English Dictionary specifies the period when Middle English was spoken as being from 1150 to 1500. This stage of the development of the English language roughly followed the High to the Late Middle Ages. |Englisch, English, Inglis| |Region||England (except for west Cornwall), some localities in the eastern fringe of Wales, south east Scotland and Scottish burghs, to some extent Ireland| |Era||developed into Early Modern English, Scots, and Yola and Fingallian in Ireland by the 16th century| Middle English saw significant changes to its vocabulary, grammar, pronunciation, and orthography. Writing conventions during the Middle English period varied widely. Examples of writing from this period that have survived show extensive regional variation. The more standardized Old English language became fragmented, localized, and was, for the most part, being improvised. By the end of the period (about 1470) and aided by the invention of the printing press by Johannes Gutenberg in 1439, a standard based on the London dialects (Chancery Standard) had become established. This largely formed the basis for Modern English spelling, although pronunciation has changed considerably since that time. Middle English was succeeded in England by Early Modern English, which lasted until about 1650. Scots developed concurrently from a variant of the Northumbrian dialect (prevalent in northern England and spoken in southeast Scotland). During the Middle English period, many Old English grammatical features either became simplified or disappeared altogether. Noun, adjective and verb inflections were simplified by the reduction (and eventual elimination) of most grammatical case distinctions. Middle English also saw considerable adoption of Norman vocabulary, especially in the areas of politics, law, the arts, and religion, as well as poetic and emotive diction. Conventional English vocabulary remained primarily Germanic in its sources, with Old Norse influences becoming more apparent. Significant changes in pronunciation took place, particularly involving long vowels and diphthongs, which in the later Middle English period began to undergo the Great Vowel Shift. Little survives of early Middle English literature, due in part to Norman domination and the prestige that came with writing in French rather than English. During the 14th century, a new style of literature emerged with the works of writers including John Wycliffe and Geoffrey Chaucer, whose Canterbury Tales remains the most studied and read work of the period.
A cough is a sudden burst of air from the lungs. It can help to clear mucus or foreign items from the airways. There are different types of cough: A subacute cough often follows a respiratory infection or irritation. A chronic cough has many causes. Common ones are: Copyright © Nucleus Medical Media, Inc. Things that raise the risk of coughs are: Coughs can have fluid or be dry. A cough may be worse when waking up or when lying down. The doctor will ask about your symptoms and health history. A physical exam will be done. An acute cough is usually diagnosed by symptoms that occur with it. If coughing is severe or long lasting, tests may be done to look for the cause. Tests may be: Images may be taken to look at the lungs and other structures. They may include: Other tests may include: The goal is to treat the underlying cause of a cough. It is also to ease symptoms and prevent further problems. Coughs due to infections often go away on their own. Other coughs may need treatment. Some people may be referred to a specialist. Depending on the cause of the cough, some options may be: Things that may help reduce the risk of a long term cough are: American Lung Association Family Doctor—American Academy of Family Physicians Chronic cough in adults—approach to the patient. EBSCO DynaMed website. Available at: https://www.dynamed.com/approach-to/chronic-cough-in-adults-approach-to-the-patient. Accessed March 29, 2021. Cough. Family Doctor—American Academy of Family Physicians website. Available at: https://familydoctor.org/symptom/cough. Accessed March 29, 2021. Mathur A, Liu-Shiu-Cheong PSK, et al. The management of chronic cough. QJM. 2019;112(9):651-656. Last reviewed December 2020 by David L. Horn, MD, FACP Last Updated: 3/29/2021
English grammar is essential to promote communication, both verbally and in writing. It is a necessary aspect of many jobs and careers. Understanding the proper way to communicate helps to promote self-confidence, increase skill levels, and ensure job advancement and promotion. Learning grammar structures and understanding their meaning and function is a process that occurs over an extended period of time. The course content for each level reflects this idea of spiraling the learning of grammar structures. This course will help students learn and examine grammar structures and understand their meaning and function. The topics include parts of speech, grammatical functions, phrase, clause, and sentence types, and nominal and verbal categories including nature and usefulness of prescriptive rules of grammar. Find Out Your English Level - Flexible test schedule and tutor selection - Duration of 25 minutes for the class and assessment - A live one-on-one assessment of reading, listening, accuracy, and speaking competencies with our tutor - A detailed assessment on different skill areas, including strengths and weaknesses - Support and assistance from Student Advisor about your learning journey
This video says about itself: DNA From Fish May Explain How Feet Evolved From Fins 18 April 2013 Decoding the coelacanth fish genome has put scientists closer to reconstructing how animal ancestors crawled out of the sea 400 million years ago. By Philip Guelpa: Genome sequencing of “living fossil” fish sheds light on the evolution of land animals 30 April 2013 In a newly published article in the scientific journal Nature (496, 311–316), scientists report a significant step in the understanding of the evolutionary process that led certain ancient fish to develop limbs and emerge onto dry land, becoming the ancestors of all amphibians, reptiles, birds, and mammals. This transition is one of the most important in the development of life on earth. The new research is based on the decoding of the genome of a so-called “living fossil” fish, the “coelacanth” (pronounced SEE-luh-canth). This group of fishes, known from fossils dating as far back as 400 million years ago, was long thought to have gone extinct 70 million years ago, in the Late Cretaceous Era. However, the discovery of a living specimen in the West Indian Ocean off of South Africa in 1938 demonstrated that a reclusive population still survived. More recently, a second species of living coelacanth, both belonging to the genus Latimeria, was discovered in Indonesia. Coelacanths have been colloquially known as living fossils because of their close resemblance, at least outwardly, to fossil specimens dating back tens and even hundreds of millions of years. But perhaps the most interesting aspect of these fish is their apparent close evolutionary relationship to the first land vertebrates. It has long been thought, based on paleontological and anatomical evidence, that all tetrapods (four-limbed, vertebrate animals—amphibians, reptiles, birds, and mammals) evolved, somewhere in the neighborhood of 400 million years ago, from fish closely resembling the now mostly extinct group of lobe-finned fish belonging to the class Sarcopterygia. Lobe-finned fish have a well-developed bony skeleton inside their fins, in contrast to the common ray-finned (teleost) fish. Living representatives of this lineage include lungfish, which are actually able to breathe air with lungs that are homologous (have the same genetic origin) as those of tetrapods, and the coelacanth. Basic anatomical similarities between the skeletal structures in the fins of lobe-finned fish and the limbs of tetrapods strongly suggested an evolutionary link. However, the details of the mechanism for the transformation of fins into limbs had yet to be understood. The newly reported research begins to fill in that gap. The technique of DNA sequencing, which in recent years has permitted the decoding of the human genome and those of a growing number of other species, has now been used to document the coelacanth’s DNA sequence. Among the resulting discoveries is a genetic mechanism that controls the growth of both the lobe-shaped fins in the coelacanth and of limbs in tetrapods. Scientists have long wondered whether lungfish or coelacanths were more closely related to tetrapods. In other words, which group is closer to the common ancestor of the earliest vertebrate animals to walk on land? Genetic sequencing holds the potential to answer such questions. Unfortunately, lungfish have an incredibly large genome, which cannot be effectively sequenced by existing methods. It should be noted that the size of a species’ genome has no necessary correlation with the complexity of the organism, due to duplications of DNA sequences and other “baggage” accumulated during the course of evolution, which is not a particularly neat process. Despite this, the scientific team whose research was published in Nature was able to decode segments of the lungfish genome and compare it to their newly completed full coelacanth sequence as well as to those from a sample of tetrapods. This permitted the conclusion that lungfish are more closely related to tetrapods than are coelacanths. Nevertheless, since the two groups of lobe-finned fish are closely related to each other, knowledge of the coelacanth genome is revealing much regarding the evolution of the first land-dwelling vertebrates. The first and highly necessary step for the investigators was to determine whether the living coelacanth had evolved only very slowly from its ancestors millions of years ago, as suggested by its ancient outward appearance. This was critically important because the relevance of further analysis would depend on whether the genetic patterns observed in the modern coelacanth could be expected to resemble those of the common ancestor of lobe-finned fish and tetrapods. The results of this analysis indicate that coelacanths have evolved very slowly as opposed to a number of other species to which they were compared. Many factors influence the rate of evolution in any given lineage of organisms. Evolution is a dialectical interaction between a species and all the elements of its environment. A stable environment means that there is little selective pressure that would prompt adaptive changes. The relatively static environment in which the surviving coelacanths live, and a lack of predators, are likely to have been factors in their slow evolution. With that understanding, the researchers focused on studying genes that control the expression of structural genes (i.e., genes that build body parts). Such control genes regulate such factors as the degree, rate, and timing of expression of the structural genes. Among the categories of regulatory genes identified as being newly evolved in tetrapods (that did not exist in the ancestral lobe-finned fish) were ones associated with sensing of chemicals, through taste and smell, driven by the need to more fully perceive the complex terrestrial environment. Other categories of new control genes include those related to radial pattern formation (body form), hind limb development, kidney development, and the immune system. Again, all of these would have been important in evolutionary adaptation to the new constraints and opportunities of terrestrial existence. In all, the team identified over 44,000 control genes that evolved after the appearance of tetrapods. The researchers paid particular attention to the genetic control of the development of hands and feet by comparing genes of teleost (ray-finned) fishes, coelacanths, and tetrapods. They found a specific gene sequence that is common to the latter two, but not found in the former. This sequence was identified as affecting limb development. Experimental insertion of the coelacanth genes into mouse embryos demonstrated that they could provide much of the regulation needed to produce tetrapod limbs, thus demonstrating that this gene complex existed in lobe-finned fishes and was repurposed in the evolution of land animals. Also identified was a gene in coelacanths that appears later to have become important in the development of the mammalian placenta. Coelacanths give birth to live young which develop inside the mother’s body, but don’t receive direct nourishment from the mother during gestation, as is the case with placental mammals. The research reported by this team demonstrates the great power and potential of genetic sequencing in helping to elucidate the patterns and mechanisms of biological evolution, complimenting evidence from the fossil record. In a broader sense, this work shows that biological evolution is a process that can be objectively studied and understood as part of the development of the material world. - Genome sequencing of the living coelacanth sheds light on the evolution of land vertebrate (esciencenews.com) - Coelacanth genome sequenced (whyevolutionistrue.wordpress.com) - ‘Living fossil’ genome unlocked (livasperiklis.com) - Scientists Find a Possible New Link in the Evolution of Tetrapods in the Ancient Coelacanth (latinospost.com) - The giant ‘living fossil’ fish that could hold the key to how fins became feet (dailymail.co.uk) - Coelacanth genome surfaces (news.harvard.edu) - ‘Living fossil’ genome unlocked (nature.com) - Coelacanth DNA may tell how fish learned to walk (ndtv.com) - Genome of ancient-looking fish gives clues to first limbed landlubbers (science.nbcnews.com)
No single scientific definition of the term exists, and it has been applied to a variety of rock features that fall into one of four general categories: - A glacial erratic is a boulder that was transported and deposited by glaciers or ice rafts to a resting place on soil, on bedrock, or on other boulders. It usually has a different lithology from the other rocks around it. Not all glacial erractics are balancing rocks; some are firmly seated on the ground. Some balancing erractics have come to be known as rocking stones, also known as logan rocks, logan stones, or logans, because they are so finely balanced that the application of just a small force may cause them to rock or sway. A good example of a rocking stone is the Logan Rock in Cornwall, England, United Kingdom; another is the Trembling Rock in Brittany, France. - A perched block, also known as a perched boulder or perched rock, is a large, detached rock fragment that most commonly was transported and deposited by a glacier to a resting place on glacial till, often on the side of a hill or slope. Some perched blocks were not produced by glacial action, but were the aftermath of a rock fall, landslide, or avalanche. An erosional remnant is a persisting rock formation that remains after extensive wind, water, and/or chemical erosion. To the untrained eye, it may appear to be visually like a glacial erratic, but instead of being transported and deposited, it was carved from the local bedrock. Many good examples of erosional remnants are seen in Karlu Karlu/Devils Marbles Conservation Reserve in the Northern Territory of Australia. - A pedestal rock, also known as a rock pedestal or mushroom rock, is not a true balancing rock, but is a single continuous rock form with a very small base leading up to a much larger crown. Some of these formations are called balancing rocks because of their appearance. The undercut base was attributed for many years to simple wind abrasion, but is now believed to result from a combination of wind and enhanced chemical weathering at the base where moisture would be retained longest. Some pedestal rocks sitting on taller spire formations are known as hoodoos.
Fine example of this scarce map of the Duchy of Mantova and environs, published by Coronelli in his C orso Geogrpaphico. The map shows the section of the Po River and Tributaries in the Duchy of Mantova, including 8 coats of arms. Vincenzo Coronelli apprenticed as a Xylographer, before joining the Convental Franciscans in 1665. In about 1678, after studying Astronomy and Euclid, Coronelli began working as a geographer and was commissioned to make a set of Terrestrial and Celestial Globes Ranuccio II Farnese, the Duke of Parma which were 5 feet in diameter. Coronelli was next invited to Rome to construct a similar pair of Globes for Louis XIV. From 1681 to 1683, Coronelli lived in Paris, where he constructed a pair of 10 foot diameter globes for the King, at a weight of nearly 4000 pounds. The fame and importance of Coronelli's globe led to the production of a 42 inch diameter globe in 1688, for which complete of examples of which reside in a number of major institutional collections around the world. Separate globe gore sheets from this famous globe periodically appear on the market. Coronelli worked for a number of years as a Geographer and Theologian, before returning to Venice in 1705, where he published his Atlante Veneto and Corso Geographico and founded the Accademia Cosmografica degli Argonauti. Vincenzo Maria Coronelli (1650-1718) was one of the most influential Italian mapmakers and was known especially for his globes and atlases. The son of a tailor, Vincenzo was apprenticed to a xylographer (a wood block engraver) at a young age. At fifteen he became a novice in a Franciscan monastery. At sixteen he published his first book, the first of 140 publications he would write in his lifetime. The order recognized his intellectual ability and saw him educated in Venice and Rome. He earned a doctorate in theology, but also studied astronomy. By the late 1670s, he was working on geography and was commissioned to create a set of globes for the Duke of Parma. These globes were five feet in diameter. The Parma globes led to Coronelli being named theologian to the Duke and receiving a bigger commission, this one from Louis XIV of France. Coronelli moved to Paris for two years to construct the King’s huge globes, which are 12.5 feet in diameter and weigh 2 tons. The globes for the French King led to a craze for Coronelli’s work and he traveled Europe making globes for the ultra-elite. By 1705, he had returned to Venice. There, he founded the first geographical society, the Accademia Cosmografica degli Argonauti and was named Cosmographer of the Republic of Venice. He died in 1718.
Quadrature phase-shift keying (QPSK) Sometimes this is known as quadriphase PSK, 4-PSK, or 4-QAM. (Although the root concepts of QPSK and 4-QAM are different, the resulting modulated radio waves are exactly the same.) QPSK uses four points on the constellation diagram, equispaced around a circle. With four phases, QPSK can encode two bits per symbol, shown in the diagram with Gray coding to minimize the bit error rate (BER) — sometimes misperceived as twice the BER of BPSK. The mathematical analysis shows that QPSK can be used either to double the data rate compared with a BPSK system while maintaining the same bandwidth of the signal, or tomaintain the data-rate of BPSK but halving the bandwidth needed. In this latter case, the BER of QPSK is exactly the same as the BER of BPSK – and deciding differently is a common confusion when considering or describing QPSK. The transmitted carrier can undergo numbers of phase changes. Given that radio communication channels are allocated by agencies such as the Federal Communication Commission giving a prescribed (maximum) bandwidth, the advantage of QPSK over BPSK becomes evident: QPSK transmits twice the data rate in a given bandwidth compared to BPSK – at the same BER. The engineering penalty that is paid is that QPSK transmitters and receivers are more complicated than the ones for BPSK. However, with modern electronics technology, the penalty in cost is very moderate. As with BPSK, there are phase ambiguity problems at the receiving end, and differentially encoded QPSK is often used in practice. The implementation of QPSK is more general than that of BPSK and also indicates the implementation of higher-order PSK. Writing the symbols in the constellation diagram in terms of the sine and cosine waves used to transmit them: This yields the four phases π/4, 3π/4, 5π/4 and 7π/4 as needed. This results in a two-dimensional signal space with unit basis functions The first basis function is used as the in-phase component of the signal and the second as the quadrature component of the signal. Hence, the signal constellation consists of the signal-space 4 points The factors of 1/2 indicate that the total power is split equally between the two carriers. Comparing these basis functions with that for BPSK shows clearly how QPSK can be viewed as two independent BPSK signals. Note that the signal-space points for BPSK do not need to split the symbol (bit) energy over the two carriers in the scheme shown in the BPSK constellation diagram. QPSK systems can be implemented in a number of ways. An illustration of the major components of the transmitter and receiver structure are shown below.
08 Jul Decoding Player Submissions: identifying the best answers without knowing the right answer In a previous blog post, we mentioned that the core of optimizing DNA sequence alignment was finding a reasonable trade off between maximizing the number of nucleotides that are correctly aligned, and minimizing the number of gaps. The goal of the alignment of two sequences is to group together the nucleotides they have in common in order to assess how similar they are, and eventually infer how related the organisms in which they were found are. Alignments are needed because sequences evolve over time, but the difference between two related sequences, even after millions of year of separate evolution, is still distinguishable from the difference between two unrelated sequences. What are we doing exactly when we align sequences? Even closely related DNA sequences eventually develop differences due to mutations that happen over time. So while there are specific proteins that we share with, say, chimpanzees, and work exactly the same in both organisms, their sequences are likely slightly different. Most of the adaptation of species to their environment described by Charles Darwin actually consists of small mutation events that end up being positive in some environment, and the individuals with those mutations being favored in reproduction over thousands of generations. Imagine a world where everyone spends 20 hours a day playing basketball and the most successful basketball players have the most children. Whenever a child is born abnormally tall, that child would tend to grow into a strong basketball player, and thus would tend to have many children. Tall people consistently having more children than short people would increase the average height of the population at each generation. This is exactly how giraffes became giraffes, over a really long time. There are different types of mutations: a substitution occurs when a nucleotide is replaced by another. An insertion occurs when a nucleotide is added, and a deletion occurs when a nucleotide is removed. Substitutions will cause mismatches between related sequences, whereas insertions and deletions will introduce nucleotides do not map to anything (because they are new, or because their equivalent (homolog) does not exist anymore. We can model those as gaps. But there are no hard rules as to how an alignment should be made since in practice all sequences have different characteristics. In other words, if we want to align TTCATAGC and CTTGACTG for instance, we have multiple choices. 1. We could choose to go for the alignment that avoids any mismatched nucleotides 2. We could say that the alignment in 1 is not reasonable because it contains many gaps (so not a lot of information is actually matched from one sequence to the other), and as we saw earlier, it’s okay to have some mismatches since substitutions are a type of mutation which does happen. So we could decide to allow mismatches and minimize the number of gaps, and get something like this: 3. But obviously we can notice that our solution at 2 is silly, since we now barely have anything that matches! We could then try to find a balance where we value nucleotides alignment highly, but consider an occasional gap to be fine. And here we arrive at something that looks reasonable! A few gaps here and there, a mismatch, but it is believable that, a few thousand generations ago, those were the same sequence. We arrived at this result without enunciating generic rules, just by aligning things in a way that felt reasonable. Intuitively, we want to find a balance between maximizing aligned content and minimizing mismatches and gaps. It’s easy for humans to intuitively arrive at a compromise, but it is much harder to enunciate rules to teach how to do so to a computer, because there are many different “valid” solutions. There is no “right” answer. How do we define a good solution when there is no “right” answer? Let’s start from a much more down to earth example. Carlos, a coworker of ours, enjoys chicken a lot. He also likes getting a good bang for his buck, and is always looking for a deal. In his quest to get the best tradeoff between taste and price, he has visited most of the restaurants that sell chicken near McGill University in Montreal. He rated the quality of each meal out of 10. |Restaurant||Price ($)||Rating (/10)| Some restaurants are very easy to rule out. For instance, restaurants D and I offer pretty much the same plate, but I is cheaper, so Carlos, a conscious spender, never goes to restaurant D. Similarly, restaurant F is a cheap option at $7, but it’s not better than the $5 plate at restaurant C. However, Carlos doesn’t have a strong preference between restaurant I and restaurant A. I is better, but A is much cheaper, so they both have their qualities. Neither is strictly worse than the other. We can consider this in a more general perspective and define restaurants for which a strictly better alternative (both less expensive AND better quality) exists as “suboptimal”. Hence, the restaurants that are worse than no others can be considered “optimal”. The case where an option is optimal by virtue of not being strictly worse than any other option is known as Pareto optimality. To visualize the problem, we can draw a plot of all the restaurants, organized by their performance on Carlos’s two criteria. We identify three restaurants that are worse than no others. We can define a line called the Pareto frontier, which is the set of points that are Pareto optimal. The nearer the line a restaurant is, the better it is as a lunch option. Okay, but how in the world is this remotely related to Borderlands Science? What we are doing with Borderlands Science is exactly the same idea; we are trying to optimize the tradeoff between maximizing the number of correctly aligned nucleotides, and minimizing the number of gaps. Thus, we are most interested in solutions that are not worse than other solutions. So, given all solutions provided for a puzzle, we can position them on a two-axis plot just like we did for the restaurants, and obtain data like the following: In order to assemble a new alignment, we use data from optimal or near-optimal solutions (near the red line). Note that on this plot of real data, darker blue points mean there are multiple solutions with the same score and number of gaps. As you see, there is a nice spread of different strategies for solving the problem; some players like to go fast and use the minimum number of tokens they can to get the par scores, and some like to fight for the high score. Moreover, not all players are given the same number of tokens to ensure we sample the whole solution space. Thanks to this variety, we can obtain a good approximation of a consensus answer to the question “how do players intuitively address the tradeoff between score and gaps?”, based on submissions that are both varied and high-quality.
It's About Supply and Demand In this lesson, students watch an Instructional Television (ITV) video and participate in a simulation to learn about supply and demand and how those two forces affect price. The supply and demand simulation will also bring out the concept of self regulation. Students who want objects in high demand will have to decide if they are worth the price. Grades 9 to 12 Two 45 minute class periods Law of Supply and Demand Needs and Wants Students will be able to: - Explain the ideas of supply and demand. - Use graphs and other tools to determine the impact of price on number of sales. - Use the concept of self regulation in describing the difference between wants and needs. McREL Economics Standard 3: Understands the concept of prices and the interaction of supply and demand in a market economy 1. Understands that the demand for a product will normally change (i.e., the demand curve will shift) if there is a change in consumers' incomes, tastes, and preferences, or a change in the prices of related (i.e., complementary or substitute) products 2. Understands that the supply of a product will normally change (i.e., the supply curve will shift) if there is a change in technology, in prices of inputs, or in the prices of other products that could be made and sold by producers 3. Understands that changes in supply or demand cause relative prices to change; in turn, buyers and sellers adjust their purchase and sales decisions McREL Self-Regulation Standard and Benchmarks (3rd Ed.) Standard 2: Performs self-appraisal Level IV (Grade K-12) 4. Performs analysis of employability 5. Understands career goals 6. Develops an inventory of wants versus needs NCTM Algebra Standard, Grades 9-12 Represent and analyze mathematical situations and structures using algebraic symbols Use symbolic algebra to represent and explain mathematical relationships. - Use mathematical models to represent and understand quantitative relationships Draw reasonable conclusions about a situation being modeled. - Analyze change in various contexts Approximate and interpret rates of change from graphical and numerical data. This lesson was prepared by: Patrick Vennebush and Melissa Donohue
The right triangle altitude theorem or geometric mean theorem is a result in elementary geometry that describes a relation between the lengths of the altitude on the hypotenuse in a right triangle and the two line segments it creates on the hypotenuse. It states that the geometric mean of the two segments equals the altitude. Theorem and applications If h denotes the altitude in a right triangle and p and q the segments on the hypotenuse then the theorem can be stated as: or in term of areas: The latter version yields a method to square a rectangle with ruler and compass, that is to construct a square of equal area to a given rectangle. For such a rectangle with sides p and q we denote its top left vertex with D. Now we extend the segment q to its left by p (using arc AE centered on D) and draw a half circle with endpoints A and B with the new segment p+q as its diameter. Then we erect a perpendicular line to the diameter in D that intersects the half circle in C. Due to Thales' theorem C and the diameter form a right triangle with the line segment DC as its altitude, hence DC is the side of a square with the area of the rectangle. The method also allows for the construction of square roots (see constructible number), since starting with a rectangle that has a width of 1 the constructed square will have a side length that equals the square root of the rectangle's length. The theorem can be used to provide a geometrical proof of the AM–GM inequality in the case of two numbers. For the numbers p and q one constructs a half circle with diameter p+q. Now the altitude represents the geometric mean and the radius the arithmetic mean of the two numbers. Since the altitude is always smaller or equal to the radius, this yields the inequality. The geometric mean theorem can also be thought of as a special case of the intersecting chords theorem for a circle, since the converse of Thales' theorem ensures that the hypotenuse of the right angled triangle is the diameter of its circumcircle. The converse statement is true as well. Any triangle, in which the altitude equals the geometric mean of the two line segments created by it, is a right triangle. The theorem is usually attributed to Euclid (ca. 360–280 BC), who stated it as a corollary to proposition 8 in book VI of his Elements. In proposition 14 of book II Euclid gives a method for squaring a rectangle, which essentially matches the method given here. Euclid however provides a different slightly more complicated proof for the correctness of the construction rather than relying on the geometric mean theorem. Based on similarity Proof of theorem: The triangles and are similar, since: - consider triangles , here we have and , therefore by the AA postulate - further, consider triangles , here we have and , therefore by the AA postulate Therefore, both triangles and are similar to and themselves, i.e. . Because of the similarity we get the following equality of ratios and its algebraic rearrangement yields the theorem:. Proof of converse: For the converse we have a triangle in which holds and need to show that the angle at C is a right angle. Now because of we also have . Together with the triangles and have an angle of equal size and have corresponding pairs of legs with the same ratio. This means the triangles are similar, which yields: Based on the Pythagorean theorem In the setting of the geometric mean theorem there are three right triangles , and , in which the Pythagorean theorem yields: - , and Adding the first 2 two equations and then using the third then leads to: A division by two finally yields the formula of the geometric mean theorem. Based on dissection and rearrangement Dissecting the right triangle along its altitude h yields two similar triangles, which can be augmented and arranged in two alternative ways into a larger right triangle with perpendicular sides of lengths p+h and q+h. One such arrangement requires a square of area h2 to complete it, the other a rectangle of area pq. Since both arrangements yield the same triangle, the areas of the square and the rectangle must be identical. Based on shear mappings The square of the altitude can be transformed into an rectangle of equal area with sides p and q with the help of three shear mappings (shear mappings preserve the area): - *Hartmut Wellstein, Peter Kirsche: Elementargeometrie. Springer, 2009, ISBN 9783834808561, pp. 76-77 (German, online copy, p. 76, at Google Books) - Claudi Alsina, Roger B. Nelsen: Icons of Mathematics: An Exploration of Twenty Key Images. MAA 2011, ISBN 9780883853528, pp. 31–32 (online copy, p. 31, at Google Books) - Euclid: Elements, book II – prop. 14, book VI – prop. 8, (online copy) - Ilka Agricola, Thomas Friedrich: Elementary Geometry. AMS 2008, ISBN 9780821843475, p. 25 (online copy, p. 25, at Google Books) |Wikimedia Commons has media related to Geometric mean theorem.|
An explosion is a fast increase in volume and increase in energy made available. It normally makes high temperatures and makes gases. Many natural events can make explosions, such as lightning, volcanic eruptions, meteors, and supernovae. People make explosions mostly by using chemical explosive materials. A chemical explosion starts pressure waves in the medium where it happens. Explosions are categorized as deflagrations if the pressure waves are subsonic and detonations if they are supersonic. When a detonation happens, the resulting pressure waves are named shock waves. Unintentional explosions can be caused when chemicals are mixed together, or when pressurized containers or flammable materials are heated or exposed to flames. To cause an explosion, pressure does not have to be present but is always a result of an explosion. Several safety measures are used to prevent unintentional explosions. Many countries require that chemicals, fuels, and pressurized containers that may explode be labelled with warning labels. As well, many countries have regulations restricting the possession and use of potentially explosive materials so they will only go to appropriate industrial and research uses. Transportation regulations require potentially explosive chemicals, fuels, and pressurized containers to be transported safely. Intentional explosions are caused when armies fire artillery or when air forces drop bombs on enemies. Military engineers handle explosives and arrange intentional explosions during wartime. Intentional explosions are also used by civilians in demolition. They break up old and obsolete buildings and bridges, and break rock and stone for construction. Explosions are made for activities such as mining, construction, and large-scale civil engineering projects such as building tunnels, roads, railways, and dams.
This collection of historical fiction photo prompts lets young teens step back in time to experience a slice of history. Whether they’re sailing on the Mayflower, panning for gold in Old California, protecting a Jewish family during World War II, or creating their own “You Are There” historical adventure, these prompts will open the doors of their imaginations. Or, enhance your studies of history by inviting your junior high or high schoolers to use these prompts for writing across the curriculum. 1. Pilgrim’s Progress The year is 1620. Imagine that you and your parents are aboard the Mayflower, bound for a destination that’s an ocean away from friends, family, and every comfort you have ever known. Write a journal entry expressing your hopes and fears about starting a all over again in the New World. 2. Gold Fever Eureka! It’s 1849, and folks are flocking to California in search of gold. Imagine that you are a miner with “gold fever” living in a mining camp called Hangtown. Write a letter home telling your family about a typical day. What is life like in the camp? Is there law and order where you live? Have you been successful at prospecting for gold? Did you strike it rich? 3. Hiding Place During World War II, you and your parents hid a Jewish family in your home in Holland to protect them from the Nazis. Who was this family? How did you keep them safe? Write a paragraph explaining why you chose to do this, even though it meant putting your own family at great risk. 4. Doorways to History These may look like ordinary wooden doors salvaged from old buildings, but things are not always as they seem! You see, each door leads to a different place and time. Which door will you step through? What moment in history will greet you? What historical figure will be your guide? Write a story about your adventure. If your children have enjoyed these exciting journal prompts, be sure to check back each week for more Writing Prompt Wednesdays! Photos: Vladislav Bezrukov (Mayflower), Library of Congress (gold miners), anyjazz65 (doors), courtesy of Creative Commons Sign up for the WriteShop list to get your free 240 printable writing prompt cards.
Ground Beetles: are typically found on the ground, usually underneath objects such stones, wood, and other objects in contact with soil. Interestingly, most ground beetle species are nocturnal or active at night. Ground beetles typically enter structures by crawling under doors or entering through open windows. They are considered a nuisance pest. Boxelder Bugs: Overwintering adults emerge from hibernation, when the boxelder buds open, and fly back to their host trees in late April to early May. The primary host plant is the boxelder tree, but they also occur on maple trees. In the fall, boxelder bugs will group on the south side of rocks, trees, and other objects. From there, they will move to nearby structures to hibernate for the winter. Weevils: Black and strawberry-root weevils overwinter in soil, amongst host plants’ roots. Adults emerge from early May to late July. The adults are typically nocturnal. Root weevils enter structures in the fall to overwinter. When outdoor conditions become adverse, they will enter the indoors. This is usually when their food plants die at the end of their season or because of adverse weather conditions. Sow Bugs: These land-dwelling crustaceans are arthropods, but not insects. They are found worldwide. Sow bugs are found in areas of high moisture because they have high water loss. Their habits are nocturnal in order to reduce water loss. Sow bugs are inactive during the day and remain hidden under objects such stones and wood. They occasionally enter buildings via door thresholds, particularly at ground level. Sow bugs are scavengers and feed on decaying organic matter, usually plant material. Centipedes: These are sometimes called ‘hundred-leggers’ because of their many pairs of legs. Centipedes are found in areas of high moisture such as loose bark, rotting logs and under stones. Centipedes occasionally invade structures, feeding off flies, spiders, and other dead insects. They are usually found in dark, damp areas of a structure. Earwigs: nests are known for their large, football-shaped paper nest. The nest is one of the largest of wasp nests and can be up to 14 inches (35 cm) in diameter and 23 inches (60 cm) in length. The bald-faced hornet is protective of the nest and will sting repeatedly if disturbed. This wasp is more aggressive than most yellow jackets and the nest should be observed only from a distance. It is common to find the nests hanging from trees, soffits, and other objects around the home.
The brand new Oxford Phonics Spelling Dictionary is an easy home and school reference tool. It supports the teaching of reading and spelling through synthetic phonics. Supported by the Floppy's Phonics Sounds and Letters Programme, it follows the Alphabetic Code Chart showing the sounds and alternative spellings that children will need to learn to become proficient readers and spellers. The words are ordered by initial sound and there are subsections to show how the same sounds appear in the middle or at the end of a word. The long vowel sounds and their alternative spellings appear in a separate section within the dictionary. This unique dictionary makes it easy to explain how 'sun' and 'Cinderella' both start with the 's' sound and how 'dance' has the same 's' sound at the end, while 'egg' and 'eat' start with the same letter but different sounds. With colourful illustrations by Alex Brychta and the familiar Oxford Reading Tree characters, this is a fun way to prepare for the phonics screening check. Sayfa Sayısı: 96 Baskı Yılı: 2013
The Science Behind Habits: What it takes to rewire your brainMar 09, 2021 04:14PM ● By KLAUDIA BALOGH By the third month of 2021, eight out of 10 people will have already given up on their New Year’s resolutions. They would have needed to hang in there just a little longer to make a lasting change. To make new habits last, you must rewire your brain. “When it comes to forming positive habits, it comes down to being very consistent for the first 66 days,” says James Garrett, a scientist who has dedicated nearly two decades to unpacking the brain science behind what makes human beings thrive. According to the latest studies, he adds, the actual range of habit formation is between 18 and 254 days. Habits are an important part of human behavior; however, they can either help or stand in the way of you reaching your goals. Brushing your teeth every morning, making your coffee a certain way or eating a pint of ice cream when you’re anxious are all habitual actions. In fact, research has shown that more than 40 percent of the actions people perform daily are habits. Your brain prompts your body to perform those actions upon a trigger without you giving it much conscious thought. A habit begins as a single action, which if repeated long enough, becomes a hardwired neural pathway. Note that the brain doesn’t know the difference between good or bad action; it just knows action. ice cream when you’re anxious are all habitual actions. In fact, research has shown that more than 40 percent of the actions people perform daily are habits. Your brain prompts your body to perform those actions upon a trigger without you giving it much conscious If you picture the brain as a map, you see billions of roads—some are narrow trails, others wide highways—lighting up for every thought, action and feeling, each of which travels on a certain road. The actions performed the most create the widest highways. Those become your habits. The narrow trails may be new habits you’re trying to learning—for example, not hitting the snooze button but instead waking up to go for a walk before breakfast. The human brain is a supercomputer, processing information all the time, adapting and reacting to everything you do, feel, think or are exposed to. To ease the load, however, it will grab any chance it can to take a break from analyzing so much information. Habits allow the brain to turn on autopilot and still let you complete tasks while thinking less. It’s a way for your brain to seek a state of comfort and save energy. It’s more comfortable for the brain to jump on an already well-traveled highway than to explore a narrow trail. Thus, for an average of 66 days, hitting snooze will feel easier than waking up for that morning exercise. The good news is, it does get easier with consistency. The brain adapts and the narrow trail will turn into a wider highway while previous habits fade away. It’s not so much that your willpower gets stronger, but that you’re rewiring your brain. It is what scientists call neuroplasticity, meaning the human brain can and does change throughout life by strengthening one neural connection and weakening another. Changing a habit tends to move in two directions: picking up a new one or letting go of an old one. Habits don’t pop up out of nowhere. They are tied to a certain environment, people or feelings. To master or change a habit, you generally must recognize its three characteristics: (1) what triggers the action; (2) what the action is; and (3) what reward you get upon performing that action. Take eating ice cream as an example. The cue that creates the craving is a feeling of anxiety; the action is eating; the reward is the quick dopamine (feel-good hormone) rush from the sugar. To let go of that bad habit, it’s best to replace it with a good one. For example, instead of eating ice cream when you’re anxious, have a bowl of berries or a piece of dark chocolate, or even go out and exercise. It will still activate that reward pathway, but without the unwanted calories. Those who fail the fastest are those who try to accomplish too much at once. Remember, the brain likes being comfortable, and if it’s pushed too far out of its comfort zone, it will just make your life miserable until you revert to your old ways. So, when it comes to changing your habits, one small step at a time can go a long way. “Picking up new good habits or letting go of old bad ones is a skill you can master,” Garrett says. “When you set out to master habits and you crush it every single day, even when it’s hard, you still do it relentlessly, and you’re really consistent, that’s what instills that sense of what psychologists call self-efficacy, this confidence that you can do this again. And what it gives you is a sense of personal mastery. It teaches you that whatever you set your mind to, you can master, you can get good at and you can become.” Klaudia Balogh is a health and wellness writer for TOTI Media.
For years, the Bose-Einstein condensate has fascinated physicists as to what it could do for other branches of science. Researchers hoped they might one day be able to use the quantum properties of Bose-Einstein condensates to detect the gravitational waves of space. However, new studies led to a disappointing conclusion: any chance of success for Bose-Einstein condensates to spot gravitational waves is "beyond reach of current methods." Why study gravitational waves? Gravitational waves give astronomers a host of information about our galaxy. They result from black holes or neutron stars in the depths of space. Astronomers currently use kilometer-long measurement facilities to track these instances of gravitational waves. In 1916, Einstein theorized that moving masses like giant stars leave dents in space and time, which then spreads at the speed of light. Those "dents" became known as gravitational waves -- moving similarly to other waves like radio, light, electromagnetic. The problem with original studies of gravitational waves came from their weaknesses. Most gravitational waves that reach Earth don't have enough power to power a standard commercial vacuum cleaner. This has made them an extensive challenge for physicists to hunt down. One instance in 2015, however, fascinated physicists and astronomers alike. Two huge black holes merged some 1.3 billion light years from Earth. One of those black holes measured the mass of 36 suns and the other measured 29 suns. When the effects of that merger reached Earth in September 2015, the weak signal was enough to register movement in two four-kilometer-long vacuum tubes in the United States. That instance fascinated researchers at the Helmholtz-Zentrum Dresden-Rossendorf laboratories. "As the gravitational waves reached Earth, they shortened one of the two measurement distances by a tiny fraction of a trillionth of a millimeter at both facilities, while the other perpendicular stretch was extended by a similar amount," said HZDR researcher Ralf Schützhold, outlining his colleagues' results. After a year of analyzing data, researchers had successfully detected gravitational waves over 100 years after Einstein first predicted them. Those researchers won the 2017 Nobel Prize in Physics. How Bose-Einstein condensates could spot gravitational waves While astrophysicists celebrated the 2016 research, others wanted to know if gravitational waves could be spotted using much smaller equipment and at smaller facilities. They looked to Bose-Einstein condensates for a potential answer. Originally predicted by Satyendranath Bose and Albert Einstein in 1924, the condensates exist at extremely low temperatures. Most atoms of metals like rubidium exist in the same quantum state, despite being chaotic as vapors at higher temperatures. "Such condensates can be thought of as heavily diluted vapor from individual atoms that are cooled to the extreme and therefore condense," explained Schützhold. "Similar to laser light particles, the atoms of these Bose-Einstein condensates move, so to speak, in synchronization," Schützhold said. Physicists hoped that the gravitational waves could change the phonons (sound-particles) in synchronized atom-condensates. Researchers would then be able to spot and measure those changes. "This is a bit similar to a big vat of water in which waves generated by an earthquake change the existing water waves," Schützhold explained. Why Bose-Einstein condensates don't work The short answer as to why the condensates can't be used? They don't exist at a magnitude large enough to register the gravitational waves. "Today, Bose-Einstein condensates with, for example, one million rubidium atoms are obtained with great effort, but it would take far more than a million times that number of atoms to detect gravitational waves," Schützhold said. That's not to say it couldn't one day be possible, the HZDR researchers noted. The team wants to look more closely at super-cooled helium. While helium doesn't qualify as a true Bose-Einstein condensate, it would have 10 percent of synchronized atoms. The researchers want to explore if that's a high enough percentage to register gravitational waves. "Whether superfluid helium is, however, really a way to detect gravitational waves can only be shown with extremely complex calculations," Schützhold concluded.
Honey is such a unique substance. It doesn’t spoil, it has antimicrobial properties, it can be used as food or medicine for humans. In fact, honey is the only product of insects that humans can eat. Let’s break down some facts about how honey is made. Bees have been making honey the same way for approximately 150 million years – that is, since sometime in the late Jurassic Period. Bees were working away in their hives while the dinosaurs were roaming the earth. They know “if it ain’t broke, don’t fix it”. It takes roughly two million flowers to make one pound of honey. To get to all those flowers, bees will travel 55,000 miles or more in total. There’s a reason we say “busy as a bee”! Bees work so hard because they don’t live very long. During honey production season, a worker bee lives about six weeks. During other times of the year, they can live much shorter or longer lives, depending on food supply and temperature. And for all that work over that short lifetime, what does a single bee have to show for it? The average bee produces only about 1/12 of a teaspoon of honey in her six week lifespan. When you think about how much honey the average hive can produce, you can see how the hive depends on numbers to keep up its supply.
The Human Vision Model Machine vision systems tend to mimic the human vision system. An optical sensor and electronic main processor typically act as the eyes and brain and, as in humans, they work together to interpret visual information. Also like their human counterparts, the sensor and processor are each somewhat responsible for filtering out the useless information within the scene before it is analyzed. This reduces the overall processing requirements and allows humans and well-designed machine vision systems to make decisions based on visual information very quickly. Filtering the information within a scene begins with matching the vision system to its industrial requirements. Just as humans can adjust to a variety of situations by dilating their pupils or by tuning themselves to look for a particular shape or color, machine vision systems must also be somewhat flexible. Typically, however, the most efficient system is one which is designed with only limited applications in mind. For this reason, machine vision designers have developed a variety of application-specific techniques and systems to meet the speed and accuracy standards that modern industry demands. Science EncyclopediaScience & Philosophy: Linear expansivity to Macrocosm and microcosmMachine Vision - The Human Vision Model, One-dimensional Methods, Three-dimensional Methods, Triangulation Techniques - Two-dimensional methods
First designated as a national monument in 1925, Glacier Bay National Park and Preserve was expanded to 3,283,246 acres (1,328,700 hectares) by ANILCA in 1980. This Act also designated 2.77 million acres of marine and terrestrial wilderness within the park. Glacier Bay National Park and Preserve is a coastal, mountainous, wilderness landscape that includes the fourth-largest area of glacial ice on Earth. It protects and preserves extensive icefields, alpine glaciers, and tidewater glaciers that emanate from mountain ranges rising abruptly from the coast. A long history of glacial and tectonic activity along an active plate boundary has produced a complicated and dynamic geography and geology. A great diversity of bedrock types, terrain, and local climates has allowed the development of myriad habitat types in terrestrial, freshwater, and marine environments. A coastal rainforest of western hemlock and Sitka spruce is the dominant lowland vegetation in the region. Vegetation types such as deciduous forests and shrub lands dominate in recently deglaciated areas. Lakes, streams, wetlands, and marine ecosystems are also developing in areas recently exposed by retreating glaciers. Over 300 streams are present in the park, and around one-third are newly formed since glaciers receded. Most streams with a connection to the ocean host Pacific salmon runs. About 30 species of land mammals occur in the park, including beaver, red fox, hoary marmot, porcupine, river otter, mink, marten, wolverine, and ermine. Black bears are widespread and common, while brown bears are less numerous and found primarily in open habitats and close to salmon streams. Moose occur widely throughout thickets, meadows, and open forests of lower elevations; deer are found in the 16 mature plant communities fringing Icy Strait. Mountain goats occupy high elevations with suitable habitat. Within the park’s jurisdiction are over 600,000 acres of marine waters, including 53,000 acres of designated wilderness waters. As a result, Glacier Bay National Park and Preserve is one of only a handful of large conservation areas in the world that includes extensive saltwater habitat. It is also the largest marine area managed by the National Park Service. The park’s approximately 1,180 miles of coastline represent nearly 30% of the total marine coastline in the National Park System–nearly three times more than the next-largest coastline park. Due to large tidal fluctuations, the marine photic zone continuously receives dissolved nutrients from depth, while large surface inputs of fresh water provide stability during periods of sufficient daylength to sustain phytoplankton growth. These conditions stimulate high primary and subsequent secondary production of phytoplankton and zooplankton–the foundations of the marine food web–which support an abundance of forage fishes and other marine vertebrate predators. Invertebrates such as Dungeness crab, Tanner crab, sea anemones, and shellfish are abundant in park marine waters. These resources, in turn, support many species of marine mammals, including harbor seals, Steller sea lions, humpback and killer whales, Dall’s and harbor porpoises, and a northern sea otter population. About 240 species of birds have been recorded, including a diverse array of seabirds, passerines, shorebirds, raptors, and waterfowl. Notably, Glacier Bay is a summertime home for approximately one-third of the global population of Kittlitz’s murrelet, a seabird species closely monitored by the Southeast Alaska Network. The park provides valuable opportunities to study and enjoy coastal flora and fauna in an unimpaired state, and to educate the public about the biological richness of interconnected marine, glacial, and terrestrial environments. Last updated: December 9, 2019
Humanities: Ancient Civilization (Language Arts, World History & Geography) Humanities in grade 6 is an interdisciplinary experience combining Language Arts and Social Studies. Grade six Humanities is a one-year program preparing the students in organizational skills through the study of Ancient Civilizations. Students in grade six expand their understanding of history by studying the people and events that ushered in the dawn of the major Western and non-Western ancient civilizations. Geography is of special significance in the development of the human story. Continued emphasis is placed on the everyday lives, problems, and accomplishments of people, their role in developing social, economic, and political structures, as well as in establishing and spreading ideas that helped transform the world forever. Students develop higher levels of critical thinking by considering why civilizations developed where and when they did, why they became dominant, and why they declined. Students analyze the interactions among the various cultures, emphasizing their enduring contributions and the link, despite time, between the contemporary and ancient worlds. By using a wide variety of historical and fictional texts for the study of history, students engage in rigorous skill building in the fields of literary response and analysis, reading comprehension, and vocabulary development. They examine newsworthy current events that affect their present time. The program uses hands-on student centered project-based curriculum. By the end of grade six, students have mastered the four arithmetic operations with whole numbers, positive fractions, positive decimals, and positive and negative integers; they accurately compute and solve problems. They apply their knowledge to statistics and probability. Students understand the concepts of mean, median, and mode of data sets and how to calculate the range. They analyze data and sampling processes for possible bias and misleading conclusions; they use addition and multiplication of fractions routinely to calculate the probabilities for compound events. Students conceptually understand and work with ratios and proportions; they compute percentages (e.g., tax, tips, interest). Students know about pi and the formulas for the circumference and area of a circle. They use letters for numbers in formulas involving geometric shapes and in ratios to represent an unknown part of an expression. They solve one-step linear equations. This course dynamically investigates and analyzes important concepts of Earth Science and how they relate to the physical world through thematic questions. During class time, we develop skills using various formats: lectures, labs, readings, exams, computer-assisted research, Socratic discussions, and individual and group projects. We strive to instill in the grade six student a true curiosity and interest in the earth, formation of the universe, and how that directly interacts with their physical surroundings.
Updated: Jun 10, 2019 Typing teething into google yields over 20 million hits. It’s a big topic in parenting. The normal eruption of teeth seems to be fraught with bad information, legends, horror stories and urban myths. Sleep coaches need to be well informed about teething as it is often blamed for a multitude of sleep problems. Is this fair? In this article, I will try to demystify the process of teething. What is the teething process? Tooth development starts just a few weeks after conception, and all teeth are present within the jaw bone at birth, but most babies won’t show any signs of those undercover teeth for several months. Ultimately, as adults, we have 32 teeth, but children have 20. There are 3 stages of tooth development: 1. The primary dentition stage: When the first ‘baby’ teeth erupt 2. Mixed dentition stage: When the child, usually after the age of 5 years, begins to lose teeth, and some permanent teeth erupt, so that there is a mixture of baby and permanent teeth 3. Permanent dentition stage: When the last baby tooth is lost (usually around 11-12 years) and lasts for the rest of the person’s life. The actual mechanisms of teething are not well understood, but it is thought that hormones are responsible for skin cell death in the gum. This cellular death causes the gums to break apart and allows space for the erupting tooth below the gum-line. The words people use for teething are often unhelpful, and lead us to attribute more pain to teething than is probably the reality. We talk about ‘cutting’ teeth, for example, but the teeth do not physically slice the gums. The cellular death that occurs in the gums does cause inflammation, which is why the gums often appear swollen or hard. Babies instinctively want to bite and chew hard objects, as this helps the dying cells to break down faster and allow the emerging tooth through. When do teeth first appear? Of course, there is huge variability with the eruption of teeth. Some babies get their first tooth at just a few weeks, or they are even present from birth, while other baby’s first birthday’s come and go long before the first pearly white. Teeth usually erupt in pairs, and on average, the tooth eruption process is as follows: · The 2 lower central incisors – around 6 months · The 2 upper central incisors – around 8 months · The 2 lateral upper and lower incisors – around 10 months · The first 4 molars – around 14 months · The 4 canines – around 18 months · The second 4 molars – between 2-3 years Many people think a baby is teething at around 3 months. This is usually due to the fact that a baby will typically start to drool, and also be able to start getting their hand accurately to their mouth and chew it. Often people put these two signs together and assume that teeth are to blame. They almost never are. The other thing that happens frequently is that the actual process of teething is often felt to be long, arduous and protracted. Unsettled behavior, fussing and unexplained sleep disturbance is often unfairly blamed on teething, when in actual fact it is more likely to be caused by something else. What is teething blamed for? Over the centuries, teething has been blamed for all manner of evils, from diarrhea and nappy/diaper rash, to intractable pain and even death. In fact, in 1842, records show that in nearly 5% of all infant deaths, teething was named as the cause, and it apparently caused 7% of all deaths in 1-3 year olds. Of course, nowadays, we know that infant and child mortality rates sadly used to be a lot higher, and teething just happened to coincide with a whole load of other infant and child illnesses that we are now better at treating. But it is an important part of our history. Nowadays, it is more likely that people will blame teething for any unexplained period of fussing or sleep disturbance. The common symptoms that teething is blamed for include: · Gas and wind · Coughs, runny nose and colds · Nappy/diaper rash · Sleep problems We will examine these one by one in a moment, but first of all, it is important to state that the actual process of dentition usually takes about 3-6 days. That’s it. This is really important, because unexplained cranky behavior, fussing, sleep disturbance and illness that is longer than this is very likely to be caused by something else. The truth is, babies are nearly always going through one developmental stage or another. If it’s not a gross or fine motor developmental learning curve, it’s social awareness. If it’s not learning to babble, it’s learning to sit up, or crawl. If it’s not separation anxiety, it’s probably mastering some complex hand-eye coordination task! So, if a baby always seems to be cranky or fussy for a few weeks on end, it’s more likely to be caused by back-to-back developmental phases, rather than a tooth – which is usually quite a distinct, short phase of obvious fuss. This is important to know, for many reasons, but one is: unnecessary medication. You see, if parents attribute long drawn-out phases of fussing to teething, their very reasonable assumption is that teething is a long, protracted, painful process. What parent wants their child to be in pain for days or weeks on end? But the problem is that a) pain relief won’t help if it’s a developmental phase, b) unnecessary pain relief can be harmful, and c) it leads parents to believe that their child is really suffering from teething pain which is intractable and not resolvable with simple analgesia. This serves to reinforce the belief that teething is a very painful process. It also potentially means that a child will be given pain relief at the first onset of fussy behavior – which could be around 4 months, only for the first tooth to not arrive until 8 or 9 months. That’s 5 months of unnecessary medication, and a reinforced belief that teeth take months to emerge and it is a very painful and slow process. Gas/wind: There is no evidence that teething causes this. It is more likely to be due to something the baby ate. Don’t forget, babies are often getting teeth around the same time they are trying lots of new foods. It could just be that one of them has caused their system to react with more gas than usual. Fever: While teething is an inflammatory process, it will not cause a significant fever. A very low grade fever of up to about 38°C (100.4°F) may be caused by teething, if there are other obvious signs as well, but a fever higher than this is almost certainly caused by an illness, such as a virus. Coughs, runny nose and cold: There is no evidence that teething causes a viral illness such as a cold or cough. It doesn’t really make a lot of physiological sense. Teething is an inflammatory process, so it is plausible that the immune system is under more strain than usual, but even that is a stretch. What is more likely is that babies of the age to start teething are more exposed to new environments, germs and new people who are spreading coughs and colds. Approximately 10 colds per year is entirely normal for young children – which can feel almost endless during the winter months. Babies often start daycare or nursery around the time they start teething so it is likely that this is a coincidence. Diarrhea: It is highly improbable that teething causes diarrhea. Lots of parents anecdotally report that their baby has a ‘vinegar’ smelling nappy around the time of teething, but true diarrhea (very loose, runny, watery, foul-smelling stool) is not likely to be caused by teething. It is far more likely that the baby has touched something or been exposed to a bug that has upset their tummy. Don’t forget, around the time babies start teething, they are also crawling around, putting everything in their mouth, touching the dog’s rear end, putting other children’s chewed toys in their mouths – you get the picture! Nappy/diaper rash: Again, this is a common young childhood complaint. While lots of parents report some nappy rash around the time of teething, it is just as likely to be caused by something their little one ate that has caused a particularly offensive stool. If the baby has had a ‘vinegar poo’ then it is possible that the skin may be more irritated than usual, but a significant nappy/diaper rash should not just be attributed to teething, in case it is a fungal or bacterial rash that needs medical attention. So what can teething cause? So, now you know what teething probably doesn’t cause, you’ll most likely want to know what it does cause. Here we go: Pain: Ok, now we get to the crux of it! Teething causes the gums to break down, inflammation and swelling. This can be painful, no denying it. Nobody wants their little one to be in pain. Actually, some babies don’t seem to be bothered by teething at all. And others will really let you know about it. In fact, both my own two children were completely different. One shouted and screeched for 3 days, the other just woke up and there it was – we knew nothing about its impending arrival. It is not uncommon for parents to experience a totally different reaction from different children. I can only put this down to differences in pain perception, different inflammatory responses, and different anatomy. I’ll come back to what you can do to relieve teething pain later on. Sleep problems: Right, now we’re talking! Do teeth cause sleep issues? Well, probably, if they cause pain. See above! Some children genuinely seem to wake up with a new tooth that nobody knew was imminent. Other babies and children will give you advance warning. Teething can cause a variety of problems with sleep. Common symptoms include: · More frequent breastfeeding (the action of breastfeeding soothes the pressure in the jaw and mouth) · Chewing on lots of hard objects – including knuckles, wooden toys, feet, utensils and any other hard object they can lay their hands on! · Reluctance to eat · Pulling at their ears · Bright red cheeks These symptoms are actually quite specific, and focused around the jaw and mouth itself. It should be fairly obvious when a child is teething – it will be 3-5 days of gnawing and chewing, and possible fussing. So, does this affect sleep? Well, it may do. It is important to note that teething does not always seem to cause a baby any trouble. But other babies seem to have trouble with teething for a few possible reasons: 1. There are fewer distractions in the nighttime. In the day, a baby may be more easily pacified with a toy, a change of scene, or a cuddle. At night, it is dark, quiet, and there is less stimulation. As distraction is a well-known form of pain relief, it makes total sense that nights would be worse than days. 2. Babies usually lie down to sleep. In the daytime, when they are upright, there is less blood flow to the head. Lying down may increase the pressure in the head. This is also true of any sinus-related pain – it is always better once you are standing upright, due to gravity. 3. Overtired babies release more cortisol to cope with fatigue. If babies are struggling with sleep anyway, they may have higher circulating cortisol, which increases the pain response, and also slows down would healing, suppresses the immune system, and leads to more anxiety and stress. So the link between tiredness, poor sleep and teething may be closely related, though more complex than it might first appear. Is there anything we can do about teething? Many parents want to know what to do about teething. Any pharmaceutical shelf will have a wide array of gels, powders, and granules to rub on the gums to ease teething pain. Some good general advice is that if a parent is not sure if their baby is unwell, or teething, they should get them seen by a doctor. For example: a baby with a fever, who is reluctant to feed, and pulling their ears may have an ear infection, rather than about to get a new tooth. Rubbing teething gel on their gums will do nothing to address the underlying condition. If a parent is certain that this is new behaviour, specific to teething, then they could certainly try a teething gel or homeopathic remedy. But I would urge sleep coaches and parents alike to not use these for more than a few days. If the baby is still upset after this, it is more likely to be something else. There are many parents who feel more comfortable trying non-pharmacological remedies. Some simple ones include: · Putting a clean flannel/washcloth in a plastic bag and freezing it. Let it thaw a little before giving it to the baby – frozen flannels can stick painfully to lips! · Offer cold, hard, watery foods to chew – such as cucumber, melon and frozen banana (again – thaw a little first) · Make a ‘momsickle’ or ‘booby lolly’ – use expressed breast milk (or formula) to make a milk popsickle that the baby can suck · Some people want to try Baltic amber teething necklaces or bracelets. The theory is that the amber is warmed against the skin and slowly releases pain relieving and anti-inflammatory properties to ease teething pain. There is no evidence to back this up. The problems with this strategy are th It feeds into the idea that teething is a long drawn out process They pose a choking risk They are a strangulation hazard Try teething chew toys that are specifically designed for teething babies. Some can be chilled first Consider naps in a baby carrier to have the baby upright Try to prioritise sleep as much as possible, using any means necessary – it will prevent overtiredness which can make the experience of teething more painful Promote a stress-free environment. Since stress can cause inflammation, try to optimize a calming atmosphere. This is also good for bonding and is more conducive to sleep! To round up: So, despite millions of hits on Google, thousands of blog posts on how to help with teething, hopefully it’s a little clearer that teething is both simpler, and more complex than you might think! Here’s a summary: Teeth are present from birth, and usually begin to emerge around 6 months Teething is often blamed for many other problems. It is important to rule out illness, tiredness and developmental stages before you assume that teeth are to blame Try to avoid prolonged use of pain relieving gels and medications Try to keep the atmosphere calm and relaxed, and minimize stress and overtiredness – these things will make teething worse.
CITES (the Convention on International Trade in Endangered Species of Wild Fauna and Flora) is an international agreement between governments adopted in 1963 at a meeting of members of IUCN (The World Conservation Union). Its aim is to ensure that international trade in specimens of wild animals and plants does not threaten their survival. CITES is a voluntary international agreement that does not take the place of a countiry’s national laws. Annually, international wildlife trade is estimated to be worth billions of dollars and to include hundreds of millions of plant and animal specimens. The trade is diverse, ranging from live animals and plants to a vast array of wildlife products derived from them, including food products, exotic leather goods, wooden musical instruments, timber, tourist curios and medicines. Levels of exploitation of some animal and plant species are high and the trade in them, together with other factors, such as habitat loss, is capable of heavily depleting their populations and even bringing some species close to extinction. Many wildlife species in trade are not endangered, but the existence of an agreement to ensure the sustainability of the trade is important in order to safeguard these resources for the future. Because the trade in wild animals and plants crosses borders between countries, the effort to regulate it requires international cooperation to safeguard certain species from over-exploitation. CITES was conceived in the spirit of such cooperation. Today, it accords varying degrees of protection to more than 30,000 species of animals and plants, whether they are traded as live specimens, fur coats or dried herbs.
Hand, foot and mouth disease is a contagious viral disease that is most often seen in preschool age children. It is caused by most commonly by coxsakievirus A16 and enterovirus, however other viruses have also been associated with outbreaks. There is usually about a 3 day period of time when kids will have a low grade fever, be a little irritable, and have a sore throat. It can start off like any other virus. However, then a rash breaks out as small painful vesicles that break open quickly in the mouth and make it uncomfortable to eat and often kids will start drooling. The hands and feet, especially on the sides of the fingers will break out in small vesicles with a pink halo around them. About half the cases will also have lesions on the buttocks. No treatment is necessarily required as it tends to last about a week before resolving. Hand, Foot and Mouth Disease This is a communicable disease which means it spreads in one of four ways:- skin to skin contact- saliva (sharing drinks for example)- airborne (through coughs or sneezes)- virus is shed in feces so washing hands after going to the restroom is also important to reduce spread. It is thought that there may be a relationship between hand, foot and mouth and the weather. The summer seems to be associated with more outbreaks. Across the world there has been a rising incidence of hand, foot and mouth- especially in Asia. It is unclear why, however some theories suggest climate change may be partially to blame. There is no specific treatment for this viral illness. Because of the pain associated with it- especially with the mouth lesions, I recommend over the counter pain relievers so much as ibuprofen or acetaminophen. It helps to have kids suck on cold treats like popsicles. Eating softer foods and less acidic foods will also be less likely to irritate the lesions while trying to eat! Although kids are most contagious for the first week, the virus can still be shed in their saliva and feces for weeks after. Proper hygiene with hand washing, covering the mouth with coughing, proper disposal of tissues after wiping a runny nose, avoiding sharing drinks is important! Schools have policies on when kids can return. Usually the kids need to be fever free and rash free before returning. Avoid sharing drinks, wash hands routinely, wiping noses on tissues and not sleeves:))
The concept of value-neutrality was proposed by Max Weber. It refers to the duty and responsibility of the social researcher to overcome his personal biases while conducting any research. It aims to separate fact and emotion and stigmatize people less. It is not only important in sociology but outlines the basic ethics of many disciplines. An example of it is as follows: a teacher is asked by the principal to provide a report of how well the students had performed in the class tests. On the basis of that report, the principal would provide necessary resources to those children including books, copies, or stationeries. If the teacher in order to show his capabilities presents a report where although maximum students had actually failed were shown to be passed with good grades, the students would not get the benefits they deserve from the principal. Again, in the field of medicine, if a doctor lets his emotions and personal biases get hold of him, he might not perform his duties properly. Value neutrality is of enormous importance to social workers because their contribution towards the knowledge of society and social phenomena immensely affect laws, legislations, people, groups, policies required to be made, social changes that should emerge and so on. According to Max Weber, it is important for sociologists to be value-neutral because otherwise their findings and analysis could provide distorted and manipulated results. They need to remain impartial while conducting the research, and should not omit or deduct any important information from the findings and should present the results without distorting any parts of it. A sociologist needs to keep him/herself away from manipulating the outcomes or findings of the sociological research even if those results contradict with his own views or beliefs. A sociologist can become value-neutral by being aware of his own values, beliefs, or moral judgements. He should be able to identify the values he held and prevents them from influencing his research, its findings, or conclusions. Being a part of the society, it becomes difficult to not incorporate one’s personal values and moral judgments to the social phenomena. So, most sociologists warn readers to understand how particular social research to some extent might not be entirely value-neutral. The readers are made to see those kinds of outcomes as one of the many possible truths. They believe that while studying certain social phenomena, it becomes difficult to sideline one’s personal values or biases. However, in spite of such difficulties, it must be the prime motive of sociologists to maintain value neutrality as much as possible. They should try to maintain objectivity, but, if that becomes too difficult, their duty is to inform the people of the subjectivity so that the people can interpret the data clearly. The duty of maintaining value neutrality, however, does not forbid him from having any opinions on the subject matter. It only means that the sociologist should not add or skip any information in order to match the outcome with his opinions or personal beliefs.
Hydrogen is prevalent in the Earth’s universe, making it safe to use in many industries by creating clean energy and storing energy from renewable energy. Naturally All fuels are dangerous to a certain extent. For safety Fuel consumption focuses on the prevention of situations with three combustion factors: fuel, ignition source. (Sparks or heat) and oxidants (air), where we can design fuel systems and set guidelines for safe fuel management and use. By appropriate engineering controls Many hydrogen properties make it safer to manage and operate than current commonly used fuels, and some hydrogen properties require additional engineering control to ensure safe use. Hydrogen systems tests such as tank leak test, garage leak simulation and hydrogen tank drop test have also been shown to safely produce, store and distribute hydrogen. As more and more hydrogen is demonstrated, hydrogen safety records can grow and build confidence that hydrogen can be as safe as the most widely used fuels today. Hydrogen flames have low heat. Because the burning of hydrogen produces heat and water. Without carbon, the hydrogen flame is much less heat radiated compared to hydrocarbons. Therefore there is a lower risk of flame. Our energy system is designed to store solar energy in the most efficient and ecological way. The hybrid hydrogen battery system adds to the advantages of both hydrogen storage systems and batteries. Electricity generation using our solar panels Able to generate electricity at 384.2 kWh per hour. Which the residual electricity from use Will be applied to the electrolyte cis Let’s do the separation of hydrogen and oxygen. (Electrolysis process) Resulting in hydrogen gas being released and stored in a hydrogen storage tank. To generate electricity for use in the absence of sunlight By bringing hydrogen gas mixed with air To be the fuel to generate electricity The results obtained from the fuel cell work are direct current, heat and pure water (H2O). THE PRINCIPLE OF HYDROGEN STORAGE SYSTEMS The main principle of the Hydrogen Storage System is to store electrical energy from the sun in the form of Hydrogen gas stored in the tank and hydrogen gas is used to generate electricity. Using fuel When the sun doesn’t shine. The Hydrogen Storage System must be connected to the Solar Electric Systems with Solar Panel, consisting of Solar cell and Inverter that changes the electricity bill. To generate electricity from solar energy during the daytime The electricity that solar panels generate is direct current (DC power) .The electricity is sent to the Inverter to convert from direct current (DC power) to AC power, and part of the electricity is sent. Electrolyser generates Hydrogen and Oxygen from water and keeps Hydrogen in the tank but releases Oxygen gas goes in the air. Hydrogen stored in the tank is mixed with air. It is fuel to generate electricity which will receive electricity sent to Inverter. To convert the current value and sent into the home electrical system to replace the solar electricity That cannot be produced during the night. Connecting the Hydrogen Storage System to Battery Storage Systems helps maintain a home’s energy balance. Which is 100% safe and the other product that is achieved through that process is oxygen and water having minimal to no impact on the environment Chiang Mai Solar has piloted the Hydrogen Storage System for “Phi Suea House”, a sustainable residential project powered by solar-harvesting solar panels. Designed to reduce the impact on residential areas and reduce carbon dioxide emissions. Learn more about “Phi Suea House” Hydrogen Storage System is a sustainable power generation system because it connects to Solar cells that utilize solar energy. Which makes use of the burning of hydrogen To get electricity and will also get water and oxygen for the environment. It is the most efficient and sustainable use of natural energy sources.
The Compton effect is the transference of energy from light and other electromagnetic radiation, such as x-rays and gamma rays, to stationary subatomic particles such as electrons. This observable effect gives credence to the theory that light is made up of particles called photons. The energy transferred is measurable and the interaction conforms to the laws of conservation of energy. That is, the combined energy of the photon and the electron before the collision is equal to the combined energy of the two particles after the collision. A secondary, and related, result of the collision of photons and electrons is known as Compton scattering, which is observed as a change in direction of the photons after the collision as well as a change in their wavelength. In the early 20th century, noted physicist, Max Planck, theorized that electromagnetic energy, such as visible light and other radiation, was composed of individual packets of energy called photons. These packets were further supposed to be without mass but to have individual natures and, at times, to behave like and share certain properties with other subatomic particles with observable masses. A series of experiments and calculations resulted in acceptance of this theory, and when the Compton effect — the scattering of electrons due to their absorption of energy from photons — was observed and recorded by physicist Arthur Holly Compton in 1923, Planck's theory was further strengthened. Compton's work on the phenomenon that became known as the Compton effect later earned him the Nobel Prize in physics. Compton observed that photons could impart energy to subatomic particles such as electrons, causing them to scatter, or move away from their original positions. Under certain conditions, this can cause the electrons to be separated from their parent molecules, ionizing them, or changing their net electrical charge from neutral to positive by removing the negatively charged electron. He further observed that after the collision, the photon exhibited an increase in wavelength, a direct result of its loss of energy to the electron and related to the angle of deflection in its change of direction, which is known as Compton scattering. This relationship is defined by an equation known as the Compton formula. A common analogy used to help explain the Compton effect is the striking of a cluster of stationary billiard balls by a moving cue ball. The cue ball imparts some if its energy to the other balls, which scatter as the cue ball moves in another direction at a reduced speed. While light has a constant speed, the reduced speed of the cue ball is analogous to the lower energy state of the photon after colliding with an electron, which is exhibited by its longer wavelength rather than reduced speed.
Electron diffraction refers to the wave nature of electrons. However, from a technical or practical point of view, it may be regarded as a technique used to study matter by firing electrons at a sample and observing the resulting interference pattern. This phenomenon is commonly known as wave–particle duality, which states that a particle of matter (in this case the incident electron) can be described as a wave. For this reason, an electron can be regarded as a wave much like sound or water waves. This technique is similar to X-ray and neutron diffraction. Electron diffraction is most frequently used in solid state physics and chemistry to study the crystal structure of solids. Experiments are usually performed in a transmission electron microscope (TEM), or a scanning electron microscope (SEM) as electron backscatter diffraction. In these instruments, electrons are accelerated by an electrostatic potential in order to gain the desired energy and determine their wavelength before they interact with the sample to be studied. The periodic structure of a crystalline solid acts as a diffraction grating, scattering the electrons in a predictable manner. Working back from the observed diffraction pattern, it may be possible to deduce the structure of the crystal producing the diffraction pattern. However, the technique is limited by phase problem. Apart from the study of "periodically perfect" crystals, i.e. electron crystallography, electron diffraction is also a useful technique to study the short range order of amorphous solids, short-range ordering of imperfections such as vacancies, the geometry of gaseous molecules, and the properties of short-range ordering of vacancies. The de Broglie hypothesis, formulated in 1924, predicts that particles should also behave as waves. De Broglie's formula was confirmed three years later for electrons (which have a rest-mass) with the observation of electron diffraction in two independent experiments. At the University of Aberdeen, George Paget Thomson and his colleague A Reid passed a beam of electrons through thin film of celluloid and observed the predicted interference patterns. Around the same time at Bell Labs, Clinton Joseph Davisson and Lester Halbert Germer guided their beam through a crystalline grid. In 1937, Thomson and Davisson shared the Nobel Prize for Physics for their (independent) discovery. Electron interaction with matter Unlike other types of radiation used in diffraction studies of materials, such as X-rays and neutrons, electrons are charged particles and interact with matter through the Coulomb forces. This means that the incident electrons feel the influence of both the positively charged atomic nuclei and the surrounding electrons. In comparison, X-rays interact with the spatial distribution of the valence electrons, while neutrons are scattered by the atomic nuclei through the strong nuclear forces. In addition, the magnetic moment of neutrons is non-zero, and they are therefore also scattered by magnetic fields. Because of these different forms of interaction, the three types of radiation are suitable for different studies. Intensity of diffracted beams In the kinematical approximation for electron diffraction, the intensity of a diffracted beam is given by: Here is the wavefunction of the diffracted beam and is the so-called structure factor which is given by: where is the scattering vector of the diffracted beam, is the position of an atom in the unit cell, and is the scattering power of the atom, also called the atomic form factor. The sum is over all atoms in the unit cell. The structure factor describes the way in which an incident beam of electrons is scattered by the atoms of a crystal unit cell, taking into account the different scattering power of the elements through the factor . Since the atoms are spatially distributed in the unit cell, there will be a difference in phase when considering the scattered amplitude from two atoms. This phase shift is taken into account by the exponential term in the equation. The atomic form factor, or scattering power, of an element depends on the type of radiation considered. Because electrons interact with matter though different processes than for example X-rays, the atomic form factors for the two cases are not the same. Wavelength of electrons The wavelength of an electron is given by the de Broglie equation Here is Planck's constant and the relativistic momentum of the electron. is called the de Broglie wavelength. The electrons are accelerated in an electric potential to the desired velocity: is the mass of the electron, and is the elementary charge. The electron wavelength is then given by: However, in an electron microscope, the accelerating potential is usually several thousand volts causing the electron to travel at an appreciable fraction of the speed of light. A SEM may typically operate at an accelerating potential of 10,000 volts (10 kV) giving an electron velocity approximately 20% of the speed of light, while a typical TEM can operate at 200 kV raising the electron velocity to 70% the speed of light. We therefore need to take relativistic effects into account. The relativistic relation between energy and momentum is E2=p2c2+m02c4 and it can be shown that, where ΔE = E − E0 = eU. The relativistic formula for the wavelength is then modified to become, is the speed of light. We recognize the first term in this final expression as the non-relativistic expression derived above, while the last term is a relativistic correction factor. The wavelength of the electrons in a 10 kV SEM is then 12.2 x 10−12 m (12.2 pm) while in a 200 kV TEM the wavelength is 2.5 pm. In comparison, the wavelength of X-rays usually used in X-ray diffraction is in the order of 100 pm (Cu Kα: λ=154 pm). The simplest objects for electron diffraction are free atoms or molecules as we find them in gases. The method of gas electron diffraction (GED) has been developed in the laboratories of BASF company in the 1930s by Herman Mark and Wierl and was broadly introduced into structure elucidation in chemistry by Linus Pauling. Benefits of gas diffraction Gas electron diffraction (GED) is one of the two main methods (besides microwave spectroscopy) for determination of the three-dimensional structure of molecules. It has been applied to many thousands of objects and provides us with precise measurements of bond lengths, angles and torsional angles. Theory of gas diffraction GED can be described by scattering theory. The outcome if applied to gases with randomly oriented molecules is provided here in short: Scattering occurs at each individual atom (), but also at pairs (also called molecular scattering, ), or triples () of atoms. is the scattering variable or change of electron momentum and its absolute value defined as , with being the electron wavelength defined above and being the scattering angle. The contributions of scattering add up to the total scattering (): , whereby ( is the experimental background intensity, which is needed to describe the experiment completely The contribution of individual atom scattering is called atomic scattering and easy to calculate. , with , being the distance between the point of scattering and the detector, being the intensity of the primary electron beam and being the scattering amplitude of the i-th atom. In essence theis is a summation over the scattering contributions of all atoms independent of the molecular structure. is the main contribution and easily obtained if the atomic composition of the gas (sum formula) is known. The most interesting contribution is the moleculkar scattering, because it contains information about the distance between all pairs of atoms in a molecule (bonded or non-bonded) with being the parameter of main interest: the atomic distance between two atoms, being the mean square amplitude of vibration between the two atoms, the anharmonicity constant (correcting the vibration description for deviations from a purely harmonic model), and is a phase factor which becomes important if a pair of atoms with very different nuclear charge is involved. The first part is similar to the atomic scattering, but contains two scattering factors of the involved atoms. Summation is performed over all atom pairs. is negligible in most cases and not described here in more detail and is mostly determined by fitting and subtracting smooth functions to account for the background contribution. So it is the molecular scattering that is of interest, and this is obtained by calculation all other contributions and subtracting them from the experimentally measured total scattering function. In a transmission electron microscope Electron diffraction of solids is usually performed in a transmission electron microscope (TEM) where the electrons pass through a thin film of the material to be studied. The resulting diffraction pattern is then observed on a fluorescent screen, recorded on photographic film, on imaging plates or using a CCD camera. As mentioned above, the wavelength of an electron accelerated in a TEM is much smaller than that of the radiation usually used for X-ray diffraction experiments. A consequence of this is that the radius of the Ewald sphere is much larger in electron diffraction experiments than in X-ray diffraction. This allows the diffraction experiment to reveal more of the two-dimensional distribution of reciprocal lattice points. Furthermore, electron lenses allows the geometry of the diffraction experiment to be varied. The conceptually simplest geometry referred to as selected area electron diffraction (SAED) is that of a parallel beam of electrons incident on the specimen, with the specimen field selected using a sub-specimen image-plane aperture. However, by converging the electrons in a cone onto the specimen, one can in effect perform a diffraction experiment over several incident angles simultaneously. This technique is called Convergent Beam Electron Diffraction (CBED) and can reveal the full three-dimensional symmetry of the crystal. For amorphous materials, the diffraction pattern is referred to as a Ronchigram. In a TEM, a single crystal grain or particle may be selected for the diffraction experiments. This means that the diffraction experiments can be performed on single crystals of nanometer size, whereas other diffraction techniques would be limited to studying the diffraction from a multicrystalline or powder sample. Furthermore, electron diffraction in TEM can be combined with direct imaging of the sample, including high resolution imaging of the crystal lattice, and a range of other techniques. These include solving and refining crystal structures by electron crystallography, chemical analysis of the sample composition through energy-dispersive X-ray spectroscopy, investigations of electronic structure and bonding through electron energy loss spectroscopy, and studies of the mean inner potential through electron holography. Figure 1 to the right is a simple sketch of the path of a parallel beam of electrons in a TEM from just above the sample and down the column to the fluorescent screen. As the electrons pass through the sample, they are scattered by the electrostatic potential set up by the constituent elements. After the electrons have left the sample they pass through the electromagnetic objective lens. This lens acts to collect all electrons scattered from one point of the sample in one point on the fluorescent screen, causing an image of the sample to be formed. We note that at the dashed line in the figure, electrons scattered in the same direction by the sample are collected into a single point. This is the back focal plane of the microscope, and is where the diffraction pattern is formed. By manipulating the magnetic lenses of the microscope, the diffraction pattern may be observed by projecting it onto the screen instead of the image. An example of what a diffraction pattern obtained in this way may look like is shown in figure 2. If the sample is tilted with respect to the incident electron beam, one can obtain diffraction patterns from several crystal orientations. In this way, the reciprocal lattice of the crystal can be mapped in three dimensions. By studying the systematic absence of diffraction spots the Bravais lattice and any screw axes and glide planes present in the crystal structure may be determined. Electron diffraction in TEM is subject to several important limitations. First, the sample to be studied must be electron transparent, meaning the sample thickness must be of the order of 100 nm or less. Careful and time-consuming sample preparation may therefore be needed. Furthermore, many samples are vulnerable to radiation damage caused by the incident electrons. The study of magnetic materials is complicated by the fact that electrons are deflected in magnetic fields by the Lorentz force. Although this phenomenon may be exploited to study the magnetic domains of materials by Lorentz force microscopy, it may make crystal structure determination virtually impossible. Furthermore, electron diffraction is often regarded as a qualitative technique suitable for symmetry determination, but too inaccurate for determination of lattice parameters and atomic positions. But there are also several examples where unknown crystal structures (inorganic, organic and biological) have been solved by electron crystallography. Lattice parameters of high accuracy can in fact be obtained from electron diffraction, relative errors less than 0.1% have been demonstrated. However, the right experimental conditions may be difficult to obtain, and these procedures are often viewed as too time-consuming and the data too difficult to interpret. X-ray or neutron diffraction are therefore often the preferred methods for determining lattice parameters and atomic positions. However, the main limitation of electron diffraction in TEM remains the comparatively high level of user interaction needed. Whereas both the execution of powder X-ray (and neutron) diffraction experiments and the data analysis are highly automated and routinely performed, electron diffraction requires a much higher level of user input. - Electron diffraction study of the sillenites Bi12SiO20, Bi25FeO39 and Bi25InO39: Evidence of short-range ordering of oxygen-vacancies in the trivalent sillenites." AIP Advances 4.8 (2014): 087125. | https://doi.org/10.1063/1.4893341 - Thomson, G. P. (1927). "Diffraction of Cathode Rays by a Thin Film". Nature. 119 (3007): 890. Bibcode:1927Natur.119Q.890T. doi:10.1038/119890a0. - Feynman, Richard P. (1963). The Feynman Lectures on Physics, Vol. I. Addison-Wesley. pp. 16–10, 17–5. - Leonid A. Bendersky and Frank W. Gayle, "Electron Diffraction Using Transmission Electron Microscopy", Journal of Research of the National Institute of Standards and Technology, 106 (2001) pp. 997–1012. - Gareth Thomas and Michael J. Goringe (1979). Transmission Electron Microscopy of Materials. John Wiley. ISBN 0-471-12244-0. - Remote experiment on electron diffraction (choose English and then "Labs") - Jmol-mediated image/diffraction analysis of an unknown - PTCLab-Program for calculation phase transformation crystallography with diffraction simulation, its free and open source python program https://code.google.com/p/transformation-crystallography-lab/ - ronchigram.com Web simulator for generating convergent beam diffraction of amorphous materials.
The flashcards below were created by user on FreezingBlue Flashcards. Define the following microbe-host relationships: commensalism, symbiosis, mutualism, ammensalism and latency. - Symbiosis: stable relationship. - Commensalism: 1 benefits and the other is unaffected. - Mutualism: both benefit ( in the mouth, bacteria filled a niche so worse bacteria can’t - get in there). - Ammensalism: 1 injured, other one is unaffected (2 types of bugs in mouth: 1 bacteria produce Antibiotic and 1 is harm). - Latency: infection that dormant within the host (TB lives inside macrophage laying dormant, HIV has latent phase) You can still infect others when you are in latent phase. Define the following classifications of microbe host interactions: parasite, strict and opportunistic pathogen, infection, endogenous disease, exogenous disease, colonization, normal flora and disease. - Parasite: host is damage insymbiosis gone bad. - Pathogen: parasite that can and - does damage the host and cause disease. - Infection: a process where a pathogen/parasite is causing disease. Comes from 1 of 2 sources: exogenous source caused by microbe from outside your own body but not all disease is exogenous or endogenous disease caused by your own flora or a latent infection (shingles) - Opportunistic pathogen: One that will cause disease in the right time and place. Any bacteria can cause disease if its in the right place at the right time. - Strict pathogen: not flora EVER. (ex. M. - Endogenous disease: diseas is produced by organisms in the person's own microbial flor that spread to inappropriate body sites - exogenous disease: diseases arise when a person is exposed to organisms from external sources - colonization: long term symbiotic disease Identify areas of the human body that should be free of microbes. Blood, brain, organs, bladder, urine Describe the flora of the skin and the defenses that prevent infections. Skin: keratonized, slightly acidic, normal flora Describe the flora of the eye as well as the defenses found there.
What Are Examples of Moral Beliefs? Examples of moral beliefs include views on how to treat others, beliefs about sex, religion and personal behavior and strategies to respect and forgive individuals. A person's views on personal hygiene, etiquette and language are also examples of moral beliefs. Ethics play a key role in a person's moral beliefs. For example, if a person feels it is unethical or unfair to others to gossip about someone's business, it violates her moral beliefs. Another example would be how a person feels about premarital sex or faithfulness during a relationship. Her moral belief may lead her to wait until marriage to engage in sexual relations. A person's views on stereotypes and judging also carry moral consequences. Choosing whether or not to judge a person based on race, gender, sexual orientation, religious preference or cultural background are all examples of moral beliefs. A person's moral belief may include views on interracial marriage, religious practices at services or Masses, appropriate behavior toward a particular gender or illegal activities. If a person views it morally wrong to steal, cheat or deny forgiveness, she is in violation of her moral ethics. Moral beliefs serve as a guide for behavior, thoughts and actions toward friends, significant others, family members and acquaintances.
Nonnative plants are exotic plants introduced from other parts of the world that often need human help to survive. Many nonnatives have been introduced as ornamental plants, and to provide shade, erosion control, and windbreaks. Invasive exotics are nonnatives that are able to spread and invade into natural areas, especially after disturbances such as fire or grazing. Exotics can outcompete native species, disrupt food chains, and change nutrient cycles. Eradicating invasive exotics is difficult, but can help native species reestablish themselves. Removal methods include bulldozing, manual removal, controlled burns, and chemical control. There are 83 exotic plant species in Glen Canyon National Recreation Area (NRA). Of the exotic species present, eight are controlled because of the threats they pose to native habitats: Russian knapweed (Acroptilon repens), African mustard (Brassica tournefortii), Russian olive (Elaeagnus angustifolia L.), Camelthorn (Alhagi macrorum), Fivestamen tamarisk (salt cedar, Tamarix chinensis), giant reed (Arundo donax), Uruguayan pampas grass (Cortaderia selloana), and ravennagrass (Saccharum ravennae). The rest are not prone to being invasive and are not a threat, or are too abundant and too difficult to control, like Russian thistle (Salsola pestifer) or cheatgrass (Bromus tectorum). Tamarisk (Tamarix chinensis) Tamarisk has invaded Glen Canyon NRA and much of the western United States. This invasive, low growing shrub or tree is common in riparian communities throughout the Southwest. It can easily be identified by its wispy foliage composed of small, fleshy leaves, and its feathery pink flowers which produce large amounts of seeds. The trunk and branches of mature plants are very dark, while the shoots of seedlings have a reddish color. Tamarisk consumes an excessive amount of scarce desert water and can evaporate or transpire up to 300 gallons per day, significantly more than a similarly sized cottonwood or willow. The dropped leaves of a tamarisk make the soil too salty for most native species to thrive. In the late 1800s, tamarisk was brought to North America from its native habitat which ranges from Spain through northern Africa and Asia. It was introduced in the western United States as an ornamental plant, windbreaker, and stabilizer for stream banks prone to erosion. Tamarisk quickly adapted to the Southwest and spread along low elevation riverbanks and wash bottoms throughout the region, crowding out native riparian plant and animal communities as it eventually extended its range from Canada to Mexico. By the 1940s, tamarisk was well established along the Colorado River. Without any natural checks on population growth, it replaced riparian vegetation communities and significantly reduced the biodiversity and the health of ecosystems along many of the region’s riparian areas. Tamarisk is resistant to drought, saline soils, cold temperatures, and fire. In addition, its rapid seed production and ability to outcompete native riparian plants like narrowleaf willow (Salix exigua) and the Fremont cottonwood (Populus fremontii S. Wats.) make this invasive exotic difficult to control. Eradication techniques include mechanical removal including bulldozing, controlled burns, and chemical control. The most effective method is to cut tamarisk plants close to the ground, and then carefully treat each stump with herbicide to prevent the root system from producing new shoots. Tamarisk removal efforts have occurred in many parks in the National Park Service system in an attempt to restore native ecosystems. Russian olive (Elaeagnus angustifolia) Russian olive is a shrub or small tree with silvery leaves, small thorns, and fragrant yellow flowers which turn to fruit. Native to southern Europe and central Asia, Russian olive was introduced to the United States as an ornamental plant in the 1800s. In the early 1900s it was recommended as a windbreaker, control for erosion, and wildlife cover. Though birds will eat the fruit of Russian olive, bird species diversity is higher in riparian areas which are dominated by native vegetation. Russian olive can outcompete and dominate native vegetation, particularly in riparian areas, and is present in Glen Canyon NRA, especially along the Escalante River. It can form a dense shrub layer, displace native species, and close open areas. Russian olive can survive in a variety of habitats including bare mineral substrates. It is resistant to infrequent fire, temporary flooding, browsing, and mechanical cutting. Herbicides are an effective control of this invasive exotic if applied correctly and over several years. Removal of this invasive exotic can restore native species to riparian ecosystems. The National Park Service has ongoing efforts to remove Russian olive from the Escalante and San Juan rivers. Ravennagrass (Saccharum ravennae) Ravennagrass grows in clumps reaching up to 10 feet in height and is related to sugarcane. Its tall stems grow purple plumes in the fall. Native to northern Africa and the Mediterranean, this grass was introduced to the United States as an ornamental plant. Ravennagrass grows in a variety of soil and canopy conditions and is highly competitive, but provides little habitat for birds and other wildlife. Ravennagrass threatens riparian habitats and hanging gardens and is becoming one of the most invasive and dangerous exotics in the West. Ravennagrass was introduced to the Glen Canyon area as an ornamental grass planted around buildings associated with Glen Canyon NRA. Populations are essentially under control in parts of the San Juan River and Colorado River below the dam, but remain in some side canyons. Ravennagrass can be manually removed, but is a costly process. Recent work has tested various herbicides to see if they are effective at controlling the species. Non-chemical control methods include bulldozing, manual removal, and controlled burns. The use of chemical herbicides to remove invasive exotics is often necessary, although controversial. When necessary, Glen Canyon NRA uses Garlon 4 with vegetable mixing oil in a 1:1 ratio. This mixture is carefully applied for the treatment of stumps only, breaks down quickly, and is not dangerous to humans or wildlife. Garlon 4 is used to control tamarisk and Russian olive. A checklist of exotic plant species documented in Glen Canyon NRA is available here. Last updated: October 26, 2017
The founding myth of the City of Rome centers on the twin brothers, Romulus and Remus. This myth encompasses the circumstances of their birth, their coming of age, and the death of Remus by his brother. What makes this myth remarkable, for me, is that this is essentially the creation myth for ancient Romans. The myths of Romans usually focused on civic ethics or piety toward the Gods. (Any myth that detailed the creation of the world was usually adapted from the Greeks.) This founding myth presents the belief of the Romans that they were called to a greater destiny in the world. However, they were unsparing in highlighting that Romulus murdered his brother or that the original Romans were criminals. The elements of this myth are twins with a divine parentage: in their case, Mars, the God of War. Numitor, their royal grandfather is overthrown by his younger brother, Amulius. After killing the male heirs, he forces Numitor’s daughter, Rhea Silva, to become a Vestal Virgin. During her service as a Vestal, Rhea Silva is visited by Mars. She later gives birth to his twins. Romulus and Remus, the twins, are sent out to be killed by their great uncle, but are saved through magical intervention. The River God, Tiberius guides the basket to a river bank. A wolf rescues them and nurses them until they are found. Meanwhile, a woodpecker sent by Mars ensures the safety of the twins. A childless couple, Faustulus and his wife Acca Larentia adopts the twins and raise them as shepherds. When the brothers are grown, they get into trouble with King Amulius’s men. When they were taken before their great uncle, who happens to be the king, Romulus kills him. Later, the brothers reinstate their grandfather and free their mother. Afterwards, Romulus and Remus leave to find their own fortune. Along the way, they argue over where to establish their new city. Goaded into fury by Remus, Romulus kills his brother. Filled with remorse, he buries Remus with great pomp, and then founds The City of Rome. Read the full myth here: Romulus and Remus
What is hemophilia? Normally when people bleed, the body clumps blood cells together to form a clot, which closes the wound and stops the bleeding. This process is encouraged by clotting factors like blood-clotting proteins and platelets. Hemophilia is a rare bleeding disorder in which the blood does not clot normally, meaning a person with it may bleed for a longer time after an injury than normal. This happens when the blood doesn’t have enough clotting factors. While things like small cuts in hemophiliacs are not usually a serious issue, deep, internal bleeding can damage organs and tissues. Hemophilia occurs more often in males than females and can vary in severity. Women are unlikely to develop the disease, but they can be carriers for it. What are the types of hemophilia? There are two main types of hemophilia: hemophilia A and hemophilia B. They are determined based on which clotting factor is lacking in the body and are caused by mutations in different genes. What are the symptoms of hemophilia? Symptoms vary depending on the individual’s clotting factor levels. When the deficiency is mild, patients may only experience bleeding after surgery or injury. If the deficiency is severe, bleeding may be spontaneous. Symptoms include: - Excessive and prolonged bleeding from cuts and injuries - Large and deep bruises - Prolonged bleeding after vaccinations, surgeries, or dental work - Pain and swelling in the joints - Blood in urine and/or stool - Seemingly random nosebleeds - In infants, irritability Emergency symptoms include: - Sudden pain, swelling and warmth in large joints - Bleeding from an injury - Intense headache - Extreme fatigue - Neck pain - Doubled vision If you experience these emergency symptoms, especially prolonged, heavy bleeding, seek out emergency care. What causes hemophilia? Hemophilia is a genetic disorder, inherited in an X-linked recessive pattern. Human traits are inherited from a person’s father and mother; each one contributes a copy of a gene, which interacts with the other copy. Genes are located in chromosomes, which carry the genetic characteristics of individuals, and are located in the nucleus of all body cells. Humans have 23 pairs of chromosomes, and the final pair contains the sex chromosomes, the X and Y chromosomes. Human males have one X chromosome and a Y chromosome, while human females have two X chromosomes. The genes associated with hemophilia A and B are located on the X chromosome. Males are more likely to have hemophilia because they only have one X chromosome; therefore, one altered copy of the gene is all that is needed to cause the condition. Since females have two X chromosomes, they would need to have a mutation in both copies of the gene to cause the disorder, which is unlikely. Mutations in specific genes (F8 gene for hemophilia A, F9 gene for hemophilia B) cause the disorder. The mutation reduces the amount of the clotting factors made, which means blood clots cannot form properly in response to an injury. Some cases do not appear to be inherited from the family; instead, they are caused by a spontaneous mutation in the genes. How is hemophilia diagnosed? Hemophilia is diagnosed using the following procedures: - When you know your family has a history of hemophilia, it can be diagnosed using prenatal testing - Detailed patient history - Blood tests What are the treatments for hemophilia? While there is no cure for hemophilia, effective therapies have been developed to treat it. Treatment includes: - Hormone treatment to stimulate a release of more clotting factor to stop bleeding - Blood and plasma transfusions - Physical therapy - First aid for minor wounds Depending on the severity of the case, treatment may need to be ongoing, or could only be needed when the patient is actively bleeding. Where can I find out more about hemophilia?
Trihalomethanes are the most common type of “disinfection byproduct,” which is a substance created from the treatment of water with organic matter. How They Form Chlorine is the most popular water disinfectant, used widely since the beginning of the 20th century to kill viruses and microorganisms in water. It has had a major role in significantly reducing global instances of cholera and typhoid given its effectiveness and relatively low cost. When chlorine gas, bleach or other chlorine-containing disinfectant contacts water, it becomes hypochlorous acid. This acid readily reacts with organic matter contained in the water to form trihalomethanes. These compounds are carcinogenic, meaning they are known to lead to cancer. In 1974, these effects were first acknowledged and in 1979, the US Environmental Protection Agency (EPA) began regulating allowable concentrations of THMs in drinking water, limiting it to 100 parts per billion. How to Reduce Their Effect Some tactics adopted by water treatment plants to attempt to avoid producing THMs mostly revolve around limiting chlorine’s contact with organic matter in water. One strategy involves delaying the application of chlorine, giving organic matter less time to react with the hypochlorous acid. If possible, and if organic matter content is too high, some municipalities switch to different water sources entirely. Coagulation methods are also being implemented, which allow organic matter to collect into particulates which can be removed from water before treating it with chlorine. Still others are switching disinfectants to ozone or chloramines, which don’t convert to hypochlorous acid. Many home water filters can remove most trihalomethanes from tap water.
Anemia Caused by Blood Loss Blood loss can also cause anemia - whether it's because of excessive bleeding due to injury, surgery, or a problem with the blood's clotting mechanism. Slower, long-term blood loss, such as intestinal bleeding due to inflammatory bowel disease, can also cause anemia. Anemia can also result from heavy menstrual periods in teen girls and women. Any of these factors will also increase the body's need for iron because iron is needed to make new red blood cells. Anemia Caused by Inadequate RBC Production Infants are born with high levels of hemoglobin and RBCs in their blood. This occurs in the fetus to help fetal blood carry enough oxygen while the developing baby is in the relatively oxygen-poor environment inside the uterus. After birth, when more oxygen is available, the baby's hemoglobin level normally drops to a low point at about 2 months of age, a condition known as physiologic anemia of infancy. After this occurs, the infant's body gets the signal to increase RBC production. This temporary and expected drop in the blood count is considered normal and no treatment is needed. Anemia also occurs when the body isn't able to produce enough healthy red blood cells. This can happen because of a deficiency of iron or certain other substances in the body or from inherited defects or diseases that interfere with the production of red blood cells. Aplastic anemia occurs when the bone marrow is unable to produce sufficient numbers of blood cells. More often, aplastic anemia is caused by a virus infection or exposure to certain toxic chemicals, radiation, or medications, such as antibiotics, antiseizure medications, or cancer medications. Some childhood cancers can cause anemia of this type, such as with certain types of leukemia in which abnormal cells crowd out the bone marrow cells needed to produce blood cells. Chronic diseases of other organs can result in anemia. For example, the kidneys and thyroid gland make hormones that are needed by the bone marrow to produce blood cells. Autoimmune hemolytic anemia Autoimmune hemolytic anemia, the immune system mistakes red blood cells for foreign invaders and begins destroying them. Other children inherit defects in the red blood cells (RBC’s), which may involve the RBC's structure or the production of hemoglobin or RBC enzymes. Common forms of inherited hemolytic anemia include sickle cell anemia, thalassemia, and glucose-6-phosphate dehydrogenase deficiency. Iron is essential for the production of hemoglobin in red blood cells. Poor dietary iron intake (or excessive loss of iron from the body) leads to iron-deficiency anemia, the most common cause of anemia in children. Iron-deficiency anemia can affect children at any age, but it is most commonly seen in children under 2 years of age, and in teens, particularly in adolescent girls who have started menstruating. During the first 6 months of life, babies are usually protected against developing iron deficiency due to the stores of iron built up in their bodies while they are in the uterus. However, by the second half of the first year of life, as infants continue to undergo significant growth, often they do not take in enough iron through breast milk alone or regular cow's milk (which contains less iron than fortified infant formula) to meet their iron needs. Regular cow's milk can also cause some infants to lose iron from their intestines, and drinking lots of it can make an infant less interested in eating other foods that are better sources of iron. For these reasons, regular cow's milk is not recommended for children until they reach 1 year of age and are eating an iron-rich diet. The growth spurt that occurs during puberty is also associated with an increased risk of iron-deficiency anemia. Girls are at particularly high risk because of the onset of menstruation; the monthly blood loss increases the need for dietary iron. In a recent report on iron deficiency in the United States, the Centers for Disease Control and Prevention (CDC) noted that, according to a 1996 survey, less than half of 1- to 2-year-olds and just over one fourth of teen girls were meeting the recommended daily intake of iron. Anemia can be caused by deficiency in the nutrients folic acid and vitamin B12, both of which are necessary for normal blood production. Pernicious anemia is a type of anemia that occurs when a person lacks a substance that is necessary to absorb and process vitamin B12. However, these forms anemia are rarely found in babies and young children. Sickle Cell Anemia Sickle cell anemia is an inherited blood disease. That means individuals are born with it and it lasts a lifetime. Sickle cell anemia affects the red blood cells. Normal red blood cells are smooth and round like doughnuts. They move easily through blood vessels to carry oxygen to all parts of the body. In sickle cell anemia, the red blood cells become hard, sticky, and shaped like sickles or crescents. When these hard and pointed red cells go through the small blood vessels, they tend to get stuck and block the flow of blood. This can cause pain, damage, and a low blood count or anemia. Anemia is a shortage of red blood cells in your blood. In sickle cell anemia, this shortage of red blood cells occurs because sickle cells do not last very long. It is hard for your body to make new red blood cells fast enough to keep up. Normal red blood cells last about 120 days in the bloodstream. Sickle cells die after only about 10 to 20 days. Sickle cell trait is different from sickle cell anemia. A person with sickle cell trait does not have the disease but carries the gene that causes the disease. Persons with sickle cell trait can pass the gene to their children. Sickle cell anemia is a serious disease and there is no universal cure. Bone marrow transplantation offers a cure, but very few patients have matched donors. Some patients also do not want bone marrow transplants because of the risks involved. Over the past 30 years, doctors have learned a great deal about the disease. They know what causes it, what it does to your body, and how to treat many of the complications. People with sickle cell anemia inherit two genes, one from each parent, that are variant (different from normal). The variant genes are call sickle cell genes. The sickle cell genes tell the body to make the variant hemoglobin (hee-muh-glow-bin) that results in deformed red blood cells. Hemoglobin is the protein in red blood cells that carries oxygen to all parts of the body. Children who inherit sickle cell genes from both parents will have sickle cell anemia. Children who inherit the sickle cell gene from only one parent will not have the disease. They will have sickle cell trait. Persons with sickle cell trait: Generally have no symptoms, live normal lives, and can pass the sickle cell gene on to their children. People with thalassemia have an inherited blood disorder that causes mild or severe anemia (uh-NEE-me-uh). The anemia is due to reduced hemoglobin (he-mo-GLOBE-in) and fewer red blood cells than normal. Hemoglobin is the protein in red blood cells that carries oxygen to all parts of the body. In people with Thalassemia, the genes that code for hemoglobin are missing or variant (different than the normal genes). Severe forms of thalassemia are usually diagnosed in early childhood and are lifelong conditions. The two main types of thalassemia, alpha and beta, are named for the two protein chains that make up normal hemoglobin. The genes for each type of thalassemia are passed from parents to their children. There are mild and severe forms of the disease, the latter often called Cooley's anemia. Cooley's anemia is the most common severe form of thalassemia seen in the U.S. Alpha thalassemia occurs when one or more of the four genes needed for making the alpha globin chain of hemoglobin are variant or missing. Moderate to severe anemia results when more than two genes are affected. Alpha thalassemia major can result in miscarriages. Beta thalassemia occurs when one or both of the two genes needed for making the beta globin chain of hemoglobin are variant. The severity of illness depends on whether one or both genes are affected, and the nature of the abnormality. If both genes are affected, anemia can range from moderate to severe.Thalassemia, which usually affects people of Mediterranean, African, and Southeast Asian descent, is marked by abnormal and short-lived red blood cells. Thalassemia major, also called Cooley's anemia, is a severe form of anemia in which red blood cells are rapidly destroyed and iron is deposited in the skin and vital organs. Thalassemia minor involves only mild anemia and minimal red blood cell changes. Hemophilia is the oldest known hereditary bleeding disorder. There are two types of hemophilia, A and B (Christmas Disease). Both are caused by low levels or complete absence of a blood protein essential for clotting. Patients with hemophilia A lack the blood clotting protein, factor VIII, and those with hemophilia B lack factor IX. There are about 20,000 hemophilia patients in the United States. Each year, about 400 babies are born with this disorder. Approximately 85% have hemophilia A and the remainder have hemophilia B.. The severity of hemophilia is related to the amount of the clotting factor in the blood. About 70% of hemophilia A patients have less than one percent of the normal amount and, thus, have severe hemophilia. A small increase in the blood level of the clotting factor, up to five percent of normal, results in mild hemophilia with rare bleeding except after injuries or surgery. Enormous strides made in assuring the safety of the blood supply and in the genetic aspects of hemophilia research allow us now to focus on issues which will improve the quality of life of the hemophilia patient and, ultimately, develop a cure. von Willebrand Disease Von Willebrand disease is an inherited bleeding disorder. Children born with the disease have one or both of the following: (1) low levels of a protein that helps the blood to clot and/or (2) the protein does not work as it should. This clotting protein is called von Willebrand factor. When some of this factor is missing or defective it can cause prolonged bleeding after an injury or accident. Links to Blood Disorders - Understanding your complete blodcount-Pdf file: A very good explanation of what is involved and how to understand blood counts and blood test results. - All about blood: Everything you would ever need to know about blood including Facts About Blood and Blood Banking, Donor Screening and Deferral,Whole Blood and Blood Components, Autologous BloodTesting of Donor Blood for Infectious Diseases, Transfusion-Transmitted Diseases, West Nile virus, Creutzfeldt-Jakob Disease (CJD), SARS, Smallpox and Highlights of Transfusion Medicine History. - Blood and blood disorders: A complete overview of every aspect of blood, blood diseases, specific conditions and much more. - Blood disorders: 18 specific blood disorders are discussed with links and other information. - Blood disorders and diseases-A Bloodbook Guide: This site discusses numerous blood disorders and diseases in depth with excellent links to other sites on the same topic.
Scientists in 2009 developed a wireless sensor network to monitor volcanoes, measured thermal conductivity in rocks, and launched the GOES-14 and NOAA-19 satellites. One study linked meteorite impacts to the production of early biomolecules, whereas another connected them to the extinction of large mammals. The White House released a groundbreaking report on climate change. The first Epstein Medal for innovation in geochemistry was awarded to John Eiler at the 2009 Goldschmidt Conference in Davos, Switz. This medal celebrates the pioneering research of the late Samuel Epstein, a geochemist perhaps most famous for his calibration of oxygen isotope distributions between carbonates and water, and thus for initiating the field of deriving paleotemperatures in marine sediments and ice cores. These paleotemperature determinations required the estimation of vanished reservoir information such as the oxygen isotopes of the ocean from which marine organisms grew. Eiler, a geologist from the California Institute of Technology, developed an expanded technique that involved the measurement of “carbonate clumped isotopes,” which considered the distribution of oxygen and carbon isotopes among element sites in carbonate minerals. This distribution is temperature-sensitive and independent of the composition of the host medium, such as seawater. Eiler’s acceptance lecture presented new data extending his previous findings that many carbonates and carbonate-bearing minerals follow a single temperature-dependent calibration of the clumped isotope thermometer. He outlined the technique’s applications to a variety of problems involving crustal rocks down to depths of 10 km (about 6 mi), including geotherms (mapped lines of equal temperature within Earth), fault friction, fossil extremophiles, and the genesis of oil, gas, and coal. Two papers in 2009 provided geological evidence for understanding the future behaviour of the West Antarctic Ice Sheet (WAIS). For about 30 years, scientists had recognized that this ice sheet was vulnerable to abrupt collapse, which could potentially increase global sea level by up to 7 m (23 ft) and possibly devastate the economies of many megacities. Sediments 600 m (about 2,000 ft) thick in drill cores from the seafloor 850 m (about 2,800 ft) below the floating Ross Ice Shelf revealed the first comprehensive record of the growth and collapse of WAIS during the past five million years. A team of 56 scientists led by sedimentologist Tim Naish of the Antarctic Research Centre in Wellington, N.Z., identified 38 sedimentary cycles, each of about 40,000 years’ duration, in good accordance with the same cyclicity recorded in marine-isotope records of global ice volume and mean deep-sea temperatures. A twin paper by earth scientist David Pollard of Pennsylvania State University and Robert M. DeConto of the University of Massachusetts compared the geologic data with a new model designed to simulate the oscillations of the WAIS; the results were in good agreement, which enhanced the prospects for prediction. Japan’s National Institute for Materials Science (NIMS) continued to explore the geochemical hypothesis put forth by NIMS emeritus fellow Hiromoto Nakazawa that life on Earth evolved from biomolecules formed by meteorite impacts in early oceans. Recent research about the composition and temperature of Earth’s early atmosphere had refuted the relevance of previous experiments devoted to the generation of organic compounds in gas mixtures that simulate the planet’s early atmosphere. NIMS materials scientist Toshimori Sekine and his colleagues published results of a new approach in 2009. Sekine conducted shock-wave experiments by using a propellant gun that accelerated a stainless-steel disc into a composite sample simulating the components of meteorites, the ocean, and the atmosphere. High-speed impacts generated extremely high pressures and temperatures within the sample for a fraction of a second. Analysis of the shocked samples by chromatography–mass spectrometry established the presence of minute quantities of an amino acid, four types of amines, and six types of carboxylic acid. The experiment confirmed that organic molecules could be generated as proposed by Nakazawa’s “big bang” hypothesis for the birth of life. Meteorites may have been influential in generating life on Earth more than four billion years ago. Since then, however, impacts, such as the one many scientists contend caused the extinction of dinosaurs 65 million years ago, have destroyed life. In 2009 American geoarchaeologist Douglas Kennett of the University of Oregon at Eugene with seven coauthors from several universities published persuasive evidence linking a cosmic impact to megafaunal extinctions and abrupt ecosystem disruptions at the Younger Dryas boundary about 12,900 years ago, a time when Earth was emerging from the last glacial period. The boundary was marked in North America by a widespread layer of black sedimentary rocks covering the bones of many large fauna (including mammoths); such remains were not found above the layer. In addition, the layer contained billions of nanometre-sized diamonds, most of which were encapsulated within carbon spherules. Although some independent experts remained unconvinced that these particles really were diamonds, new evidence indicating that they were shock-induced diamonds appeared definitive. The presence of particulate carbon and grapefruit-sized clusters of soot was consistent with the occurrence of intense wildfires, which were also associated with the asteroid-induced mass extinction of 65 million years ago. These facts supported the conclusion that the Younger Dryas Period began as Earth crossed paths with a swarm of comets. Ancient sedimentary rocks contain what little evidence there is for the life forms that followed the early synthesis of organic chemicals. In 2009 Nora Noffke of Old Dominion University, Norfolk, Va., supplemented the evidence provided by rare fossil bacteria and stromatolites, which are reeflike sedimentary structures composed of carbonates precipitated by bacteria. She systematized the criteria for the definition and identification of a distinctive group of textures in sandstones, called “microbially induced sedimentary structures” (MISS), with 17 individual morphologies at scales from 1 mm (0.04 in) to 1 m (about 3 ft). Their formation, established by comparison with the activities of cyanobacteria in modern tidal flats, occurred during periods of calm hydraulic conditions as the bacteria formed an organic meshwork of microbial mat that bound together fine sand grains. MISS were produced by interaction of microbiota with wave and current dynamics, and they suggest the presence of strongly seasonal paleoclimates. Extensive microbial mats grew over large areas of ancient shallow seafloors from at least 3.2 billion years ago until the present, and their fossil remnants promised to supplement the geobiological interpretations from the better-known stromatolites. The need to monitor active volcanoes in order to provide reliable estimates of renewed activity to ensure safe evacuation procedures was emphasized by the eruption of Mt. St. Helens in 2004, nearly 25 years after the explosive eruptions of 1980. Computer scientist WenZhan Song of Washington State University at Vancouver was the principal investigator for a project funded by NASA that lowered 15 robotic emissaries from a helicopter inside and around the crater of Mt. St. Helens in July 2009. The project (also supported by the Jet Propulsion Laboratory and the U.S. Geological Survey) was expected to provide a blueprint for the installation of sensor networks at other unmonitored active volcanoes. Such a plan could help determine reliable estimates for the evacuations of endangered populations. The battery-operated robots looked like microwave ovens on tripods, and each contained an earthquake-detecting seismometer, a GPS receiver to pinpoint location and ground deformation, an infrared sounder to sense volcanic explosions, and a lightning detector to detect ash-cloud formation. The robots communicated wirelessly with one another and with NASA’s Earth Observing Satellites, thus providing a low-cost sensor network that could operate in harsh conditions. Similar sensor webs were also planned for the exploration of other planets with hostile environments. A damaging earthquake occurred near the Italian village of L’Aquila on April 6, 2009. The earthquake, which had a moment magnitude of 6.3, was felt throughout central Italy, killing nearly 300 persons and leaving more than 40,000 homeless. It was the deadliest Italian earthquake since the 1980 Irpinia event. The main shock was followed by thousands of aftershocks that were detected and located by the Instituto Nazionale di Geofisca e Vulcanologia (INGV), using a portable network of seismometers. The L’Aquila earthquake resulted from normal faulting on the northwest-southeast-trending Paganica Fault. It and several neighbouring faults are related to extensional tectonic forces associated with the opening of the Tyrrhenian Basin to the west. Earthquakes that occur deeper than about 50 km (30 mi) have long been enigmatic to seismologists. At these depths the lithostatic pressure is large enough to inhibit brittle failure, or rock fracturing. In other words, rock at these and greater depths should undergo ductile, or plastic, flow in response to shear stress, yet earthquakes caused by rock fracturing have been recorded at depths as great as 700 km (435 mi). In January a team of geologists from Norway and Germany led by Torgeir Andersen presented new evidence in favour of a proposed mechanism for generating intermediate-depth earthquakes. They analyzed veins of rock that had been formed by flash heating in a Precambrian terrane in Norway. Known as pseudotachylytes, these rocks often occur near fault zones. In this case, geochemical analysis showed that the pseudotachylytes had initially formed at depths greater than 70 km (44 mi) before being exhumed to the Earth’s surface. Using computer modeling, the authors explained their observations by means of a self-localized thermal runaway failure mechanism, a process by which the rocks are softened by released heat. Interestingly, this mechanism does not depend on the existence of free fluid in the pore spaces of rocks and therefore provided a distinct alternative to the dehydration embrittlement hypothesis that was currently favoured as a mechanism for generating intermediate-depth earthquakes. Scientists from the United States reported the results from a seismic study of a region of seafloor in which “black smokers” vent superheated water enriched with dissolved minerals. Discovered in the late 1970s, these features had been extensively studied because they led to distinct biospheres that did not depend on photosynthesis. In 2003 scientists began monitoring the Endeavour segment of the Juan de Fuca Ridge in the Pacific Ocean off the coast of Oregon and Washington with a network of eight seismometers buried just beneath the seafloor. Using the high-fidelity seismic data, the scientists located several thousand small earthquakes that were associated with an axial magma chamber that drives the hydrothermal, or deep-sea, venting in the region. By modeling the seismic waveforms, the researchers were able to deduce the style of faulting responsible for the earthquakes. They concluded that cracking associated with the recharge of the axial magma chamber was the key mechanism for localizing and maintaining black-smoker vent fields over long periods of time. Anne M. Hofmeister of Washington University in St. Louis, Mo., and her colleagues Alan G. Whittington and Peter I. Nabelek of the University of Missouri in Columbia announced new measurements of the thermal conductivity of rocks, and their findings had profound implications for crustal dynamics. The scientists used a new technique known as laser-flash analysis to determine the time that it took for heat to diffuse from one end of a rock sample to the other. This technique properly accounts for biases caused by radiative heat loss and allowed for accurate measurement of the drop in conductivity as the sample was heated. The results of these experiments showed that thermal conductivity was reduced by as much as 50% at the base of the crust compared with previous estimates. This in turn implied that the base of the crust was much hotter than previously thought and that the large amounts of granitic magmas observed in hot mountain belts such as the Himalayas could be generated without the radioactive heat production in the lower crust increasing. Instead, heat generated by the localized deformation of the crust may form the magmas. Another implication was that the positive feedback created by temperature-dependent conductivities may have been integral to the differentiation of the Earth into core, mantle, and crust from its original chrondritic (meteorite-derived) composition. Scientists studying Earth’s magnetic field reported new constraints on the structure and dynamics of Earth’s core. Bruce A. Buffet of the University of California, Berkeley, Jon Mound of the University of Leeds, and Andrew Jackson of the Institute for Geophysics in Zürich analyzed recently discovered magnetic field fluctuations that have periods on the order of decades. Although the magnetic field fluctuations were observed at the Earth’s surface, they reflected processes of fluid dynamics that took place in Earth’s liquid-iron outer core. The fluctuations were created by torsional oscillations that occurred with a cylindrical geometry. In contrast to the elastic restoring force responsible for seismic waves from earthquakes, a magnetic restoring force creates these hydromagnetic waves. Nevertheless, using methods that seismologists developed to study seismic waves, the scientists modeled the hydromagnetic waves to constrain the structure of the magnetic field in the outer core and the rigidity of the solid inner core. The “core-quakes” that generate the hydromagnetic waves appeared to originate near the equator of the inner core, but their precise source mechanism remained a mystery. The first stage of the largest and most ambitious tornado field experiment in history ran from May 10 to June 13, 2009, across the U.S. Great Plains. VORTEX2 (Verification of the Origins of Rotation in Tornadoes Experiment 2) involved a roving armada of more than 50 scientists and 40 research vehicles, which included 10 mobile radars. The collaborative project was designed to explore the origins, structure, and evolution of tornadoes by collecting data from portable instruments placed near or inside the violent storms. Understanding how tornadoes form is expected to aid the ongoing improvement of severe weather warnings. The original VORTEX program operated in 1994–95 in the Great Plains and documented the entire life cycle of a tornado for the first time in history. Applications of the findings from this project contributed to improvements in National Weather Service severe weather warning statistics. VORTEX2 was a $11.9 million program funded by the National Oceanic and Atmospheric Administration (NOAA) and the National Science Foundation (NSF), 10 universities, and three nonprofit organizations. NOAA’s National Severe Storms Laboratory (NSSL) provided leadership and equipment for the program, which was scheduled to operate its second and final field phase from May 1 to June 15, 2010. Scientists hoped to use the VORTEX2 program to study five tornadic storms in 2009, but the year was a historically quiet one, especially during May. Early June, however, saw a marked increase in severe weather, and VORTEX2 participants collected data on a significant tornado tracking across southeastern Wyoming on June 5. Researchers believed that this tornado became the best-documented tornado in history, with data collection beginning before the tornado developed and continuing through its lifetime. Mobile Doppler radars estimated winds of the EF2 tornado at about 210 km (130 mi) per hour. In addition to collecting data on the Wyoming tornado, the scientists investigated several supercell thunderstorms that did not spawn tornadoes. Collecting such data was important, because it could help researchers understand why tornadoes develop in some cases and not in others. In other meteorological developments, the National Aeronautics and Space Administration (NASA) launched NOAA’s latest geostationary satellite of the Geostationary Operational Environmental Satellites (GOES) project. GOES-O blasted off on June 27. Renamed GOES-14, it reached its final position in orbit on July 8. Hovering about 36,000 km (22,300 mi) above Earth, GOES-14 carried enhanced instrumentation to capture high-definition images of severe weather patterns and atmospheric conditions. Such images could help meteorologists develop more accurate forecasts and warnings for hurricanes, tornadoes, floods, and disruptive solar disturbances. GOES-14 joined GOES-13 to serve as a backup satellite until one of the operational satellites (GOES-11 and GOES-12) experiences trouble. Launched in February, NOAA-19, a polar-orbiting satellite, was part of the Polar Operational Environmental Satellites (POES) project. It orbits the planet at a height of about 870 km (540 mi), much lower than the GOES satellites. The POES project was designed to detect more subtle changes in atmospheric and oceanic conditions, and its satellites could be used for longer-range forecasts as well as research on climate change. Regarding the impacts of climate change, on June 16 the White House released a landmark study on the effects of climate change on the United States. The 190-page report, entitled “Global Climate Change Impacts in the United States,” asserted that climatic changes resulting from the increase in heat-trapping greenhouse gases were already occurring. The report was commissioned in 2007 and was written by a team of 31 climate scientists from the U.S. Global Change Research Program; it outlined climate-related trends and projections for the country, as well as for specific regions. The report stated that climatic changes already under way in the United States were forecast to increase. Some of the predicted effects of global warming included rising temperature and sea level, retreating glaciers, longer growing seasons, and earlier snowmelt. The report also affirmed that the effects of climate change would differ by region. For example, water stress from reduced mountain snowpack would continue to intensify, especially in the West and Alaska. Although agriculture was one of the sectors most adaptable to climate change, the report maintained that growing crops and raising livestock would become more difficult. Among other predictions, the report also anticipated that land along the Atlantic and Gulf coasts, Pacific Islands, and parts of Alaska would be at greater risk of sea-level rise and storm surge and that climatic changes would exacerbate other environmental problems and social stresses. Echoing other publications, the study noted that the pace of climate change would ultimately depend on levels of current and future greenhouse gases and particulates released into Earth’s atmosphere. To solve this problem, many scientists called for a reduction in greenhouse gas emissions. From August 31 to September 4, the World Climate Conference-3 (WCC-3) brought more than 2,000 climate scientists and decision makers from more than 150 countries to Geneva to establish a Global Framework for Climate Services. The WCC-3 summary reported that the goal of the conference, which was convened by the World Meteorological Organization (WMO) and its partners, was to ensure that every country was equipped to access and apply the array of climate prediction and information services made possible by recent developments in climate science and technology. The conference concluded that such capabilities fell far short of meeting present and future needs, particularly in less-developed countries. In November released e-mails hacked from the Climate Research Unit at the University of East Anglia raised questions about the possible manipulation of the temperature related to global warming. Researchers countered stating that the e-mails were taken out of context. On December 19 the Copenhagen United Nations Climate Change Conference ended with a nonbinding agreement to cap an increase in average global temperatures to below 2 °C (3.6 °F) to avoid the worst effects of climate change. To achieve this goal, industrialized countries would commit to implement economy-wide emissions targets. Developed countries agreed to support a goal of mobilizing $100 billion annually by 2020 to address the needs of less-developed countries.
Some children exhibit challenging behaviours in school. Whether the challenging behaviour constitutes a standalone incident or represents an ongoing issue, teachers must have the knowledge and strategies in place to intervene and ensure all children feel safe in the classroom. Although there is no single technique which addresses all types of challenging behaviour, there are certain models and theories which can help explain these behaviours whilst preventing them from escalating. For example, if a child within your classroom feels anxious and withdrawn from the environment, they may be likely to go quiet and become disengaged or distracted. How does this behaviour affect you and or others within the classroom? Do you need to do anything about it? We often make assumptions as to what the problem may be and misunderstand or interpret the child’s behaviour as something different to the actual issue or concern. If you then react to the child’s behaviours negatively, or you don’t recognise or acknowledge that there may be a wider/deeper reason for the child becoming disengaged, and you begin to communicate or behave negatively back to the child, then you may reinforce the child’s negativity further, fuelling the situation and becoming caught up in a cycle. How does this affect other children within the classroom? What do they perceive of you as a teacher? Will they feel comfortable to discuss important issues with you? Our attitude plays a significant role in the behaviour that we exhibit. When individuals are feeling motivated and positive, they smile and empower those around them. However, when we’re feeling negative, the reverse is often true. Individuals often become impatient and argumentative. This cycle is often referred to as Betaris Box or the Cycle of Conflict. IKON explore this in all of our Child Services open courses as it is imperative to understand how your behaviour and attitude affects others as well as how others’ behaviour and attitude can influence your own. We offer strategies to remain calm, positive and professional when faced with challenging behaviours in highly emotive environments. Within our specially tailored courses for schools and child services, we explore the impact of Betaris Box, how to break the cycle and how to encourage positive behaviours throughout your working role. Enquire about our courses today by phoning Becka on 01473 927 062 or visiting our open course page for more information www.ikontraining.co.uk/open-courses/
London sits in the Thames Basin, a bowl of chalk about two hundred metres thick. This chalk layer was formed from tiny algal skeletons about ninety million years ago when the Earth was much warmer, sea levels higher and the south east of Britain lay under water. Each centimetre of chalk took about a thousand years to form. It was forced into a bowl shape at around the same time the Alps were pushed up during massive movements in the Earth’s surface. The outer rims of the basin are the Chiltern Hills to the north and the North Downs to the south. Within the bowl lies sand and clay deposited by seas during the Tertiary period around sixty-five million years ago. Much of the layer on the surface of the basin was stripped away by glaciers during the Ice Age, leaving only limited remains of a former ridge that became separate hills such as those at Harrow and Highgate. As the ice melted and retreated north during the Pleistocene period (between 1.5m BC and 10,000 BC) large volumes of water flowed from the Thames Basin, south and east, through what is now the London area. At times the region would have been completely submerged by a much wider River Thames. The wide, slow-moving water deposited gravel at its sides. As the Thames narrowed over thousands of years its gravel-depositing edges moved inwards in ever-lower terraced banks. Thus the youngest layers lay closest to the current banks of the river and the oldest further away on the valley sides. Archaeological finds of human tools from the past five hundred thousand years show how the river banks gradually moved inwards to the narrow channel of today. One hundred and twenty thousand years ago the climate in southern England was warmer than today. Much of the southern part of what is now the City of London lay under the much wider Thames, with the bank being roughly in line with the Strand and Trafalgar Square. On the south bank the whole of modern-day Southwark was under the river. Numerous rivers and streams flowed into the Thames from the higher ground to the north and south and erosion from these over the past fifty thousand years created the many valleys and hills on and around which London is now built. In the past few centuries the mixture of gravel, brick earth and clay that sits on the surface of the chalk bowl has been used to create ‘London Brick’ from which the city has been built. The soft clay made the tunnelling of the London Underground relatively easy but causes problems of subsidence of buildings that do not have good foundations. There is evidence of human occupation around what is now London as far back at least half a million years ago but early inhabitants would have drifted southwards with the coming of the last Ice Age. As the climate improved humans returned, probably following the spread of animals. Those new settlers can be linked to Brittonic-speaking Celtic tribes around northern Europe and the west of France. Sometime before 100 BC south-eastern Britain was invaded by people from north-eastern Gaul, generally known as the Belgae. Unlike the native Britons they were a militarily advanced people, using chariot warfare and sling-stones, defending themselves in large fortresses surrounded by a ditch. They were a hierarchical society, ruled by kings and nobles and they initially settled in the richer farmlands of Kent and Buckinghamshire. During the 1st century BC the Belgic Catuvellauni tribe came to dominate the area to the north of the Thames in the modern-day Middlesex, Hertfordshire and Bedfordshire, with their royal capital on the River Lea at Wheathampstead near St.Albans. To their east, in what is now north-east London, Essex and Suffolk lived the Trinovantes with their major settlement at Colchester. South of the Thames in south London, Surrey and Sussex were various people of Belgic origin (later known as the Regnenses) with their main settlement at Chichester. The Cantiaci were in Kent, whose major settlement was Canterbury. To the west, along the upper Thames valley, were the Atrebates. The Thames was the border between different warring tribes. The London area, with its poor clay soil, remained forested and largely unpopulated, being far from each of their main capitals and therefore too difficult to defend. The wide river and thick forests on each bank made it a natural barrier between the different groups of people but also an easier means of transport and trade than overland. Having established settlements, the Belgae needed a means to move their chariots between them and they created some form of roads. Although we do not know their exact routes it is most likely that in many cases they were more or less the same as that of the Roman roads that were used in the following centuries. To some extent the routes are traceable from discoveries of coins of the period, probably dropped by Belgic travellers. The Thames was probably fordable at Westminster, so the main Belgic north-south road almost certainly ran south-eastwards from Wheathampstead to modern Westminster. It then swung east, south of the Thames towards Canterbury, the line of the later Watling Street. Individual finds of coins seem to indicate a second north-west route from Wheathampstead, to Hatfield and down to the Thames, to cross somewhere near the modern London Bridge, no doubt by means of a ferry. Groups of coins to the east of London appear to show a ferry crossing-point between Gravesend and Tilbury. An east-west road probably crossed the Wheathampstead-Canterbury route, meeting around Hyde Park Corner, along modern Piccadilly, Long Acre, Old Street, Old Ford – where the River Lea was crossed – and on to Colchester. There is the suggestion of another east-west route from Windsor, Ealing, and Golders Green, crossing the Lea at Walthamstow. Julius Caesar, a brilliant military leader, expanded the Roman empire northwards to the Rhine and westward as far as the Atlantic, bringing the vast new territory of Gaul under occupation within a five year period from 58 BC. Caesar’s first expedition to Britain was made in 55 BC. During his conquest of Gaul many of the local tribesmen had fled across the Channel to Britain. There was a rebellion by the Armorican tribe in the west of Roman-occupied Gaul, aided by their brethren in Britain and in order to bring the British tribes under control Caesar led a small invasion force to Kent that August. They were hampered by bad weather however and returned after just two weeks. Caesar attempted another invasion of Britain the following year, committing two thirds of his army to the task, a great gamble when Gaul was only newly-conquered and its tribes still in a rebellious mood. He landed in Kent and marched his troops northwards towards the Thames. He was met by an alliance of Belgic tribes and, fording the river somewhere in the region of the future London, pursued them to their stronghold – most likely Wheathampstead – where the locals surrendered. Once again Caesar was forced to retreat to Gaul to deal with problems there before the winter weather broke. His conclusion at that time was that Britons were too weak to invade Roman Gaul and that more money was to be made from taxing their trade than from colonising. Caesar, an articulate author, published an account of his defeat of the British titled Bellum Britannicum. Of his encounter with the Catuvellauni he wrote: “When he [Caesar] had come there greater forces of Britons had already assembled, the chief command of management of the war having been entrusted to Cassivelaunus, whose territories a river called the Thames separates from the maritime states at about eighty miles from the sea.”¹ Caesar’s account is the earliest written record of the River Thames. ¹ Translation from the Latin, with thanks to Leonardo de Arrizabalaga y Prado. With thanks to Simon Birrell for proof-reading. Sources include: Simon Webb ‘Life in Roman London’; John Morris ‘Londinium’; ‘The Times London History Atlas’. Move forward to In Brief: Roman London >
Every diver needs to be able to identify common underwater hazards and know how to react if the unthinkable happens. Most underwater creatures are not harmful, but some are and divers need to know the difference. It is good practice in any event, not to touch or get too close. A few are deadly; a Box jellyfish for example, have been known to kill people within three minutes, blue-ringed octopus in thirty minutes and pufferfish (eaten) in seventeen minutes. Underwater creatures can be harmful in a number of ways: - Poisonous to eat Traumatogenic animals are those which could possibly cause a wound of some type i.e., inflict a bite, sting, and puncture. - Sharks - Any diver who has seen the movie "Open water" or "Jaws" will understand the anxiety that sharks can generate. Fortunately, predatory stealth attacks by large sharks are very rare and very few divers have been attacked underwater. (reassured? me neither!). Divers making contact with "harmless" sharks (tail or fin grabbing) can provoke Brightly coloured or shiny metallic objects, blood, food (dead fish), or low frequency vibrations may attract sharks. Avoid murky water inhabited by sharks in which there is poor visibility. Use caution when swimming during late afternoon and at night in areas where sharks are apt to be feeding. If you encounter a shark, move with slow purposeful movements. Simply seeing a large shark is not a cause to leave the water or abort the dive. Most sharks can be safely observed in all of their natural beauty and grace if the diver is not threatening or engaging in unwise behaviour such as feeding the sharks. If a large shark appears to be too inquisitive, make every effort to get out of the water, but do not panic. If you can exit the water rapidly, do so. Keep your eyes on the shark and never turn your back. Remember you are the most vulnerable at the surface. If you have enough air and you cannot easily exit the water, you and your buddy should seek a safe position on the bottom, with a solid object such as a reef or ledge behind you. Keep the shark in view. If it becomes threatening, fend it off with any kind of object that you can safely use. Sharks, like other predators, can be discouraged by "prey" items that fight back. A sharp blow on the shark's nose or around its eyes may cause it to swim off after easier prey. Shark feeding is a very controversial activity. The general opinion of biologists is that shark feeding causes changes in the behaviour of wild fish (including sharks) that may have a negative effect on the fish's life and the reef habitat in general. In addition, shark feeding may cause sharks to associate humans with food. Both shark feeding and chumming are environmentally irresponsible activities. - Stingrays - Although stingrays cause a traumatic puncture wound that may become infected, most of the pain associated with a stingray wound is related to the toxin that is contained in the sheath of the spine. For a more complete discussion, see the section on venomous Barracuda - These fish rarely attack humans. They are attracted to anything entering the water, particularly brightly coloured and silvery objects. Relying almost entirely on sight, they may follow divers for hours. If they do attack, they usually make one quick, fierce strike, which, although serious, is rarely fatal. Barracuda can reach a length of five feet. - Moray Eels - Moray eels occur in temperate and tropical reef habitats. Divers generally see them only as a head protruding from a crevice or small cave. Morays are not aggressive. They must constantly open and close their mouths to force water over their gills, and since they have large needlelike teeth they appear threatening. Moray eels have numerous sharp, fang-like teeth encased in a narrow muscular jaw, that are capable of inflecting a painful and deep bite. In addition, when a moray bites it generally holds on tightly and twists around. Moray eels generally only bite humans when provoked or if they make a mistake. They have very poor eyesight and when a diver is close to a moray they should not make threatening movements with their hands. In addition, when diving in reef areas, do not stick your hand or fingers into crevices or caves unless you are sure that there is nothing dangerous in there. Do not feed Morays or any other creature for that matter. This will encourage Moray eels to go to divers and may result in a serious wound. Moray bites must be treated to stop bleeding and then the bitten person must seek medical treatment as the numerous deep bites may become - Grouper - Grouper are not aggressive and not dangerous animals. If you harass or threaten a large grouper (or any fish) underwater, they react by becoming defensive, and they can bite. Do not try to touch fish underwater. Keep in mind that grouper conditioned by humans to accept food may become aggressive. - Other Fish - Most marine fish have powerful jaws with either bony plates or teeth that can severely injure fingers. Do not feed marine fish or intentionally place your fingers in their mouth. Remember too that some fish e.g., the trigger fish, can get quite vicious when protecting their eggs. Some fish have particularly strong jaws and can easily bite of a finger. Other fish such as the surgeon fish have at the base of the tails, razor sharp blades which can inflict nasty cuts. No venom, however, is involved. - Marine Mammals - In areas where seals, dolphins and sea lions live, treat these creatures with respect and keep your distance. They are not the same as the tame ones in the zoo or circus, a bite from these can be very nasty. - Crustaceans - Crabs and particularly lobsters can give a nasty nip when provoked or cornered. - Venomous invertebrates - Many invertebrates contain venom which is used either as a defensive mechanism against possible predators or as a means of immobilizing prey prior to consuming them. The reactions of these venomous species on humans can range from a mild irritation, to extreme pain, and even to death. A good rule of thumb as a diver practicing good conservation measures is to not touch anything underwater, particularly if you do not know what it is or whether or not it is poisonous. - Sponges - Sponges were regarded as plants for many centuries, sponges were classified as animals in 1835. Many brightly coloured sponges, generally red, yellow, or orange, can inflict painful skin irritations if touched. During handling, the skin is exposed to chemical irritants, which may lead to a painful allergic-type, contact dermatitis. The sponge is also filled with calcareous or siliceous spicules that can rub off on your hands or skin and and cause irritant spicule dermatitis. When the spicules penetrate the skin they may carry small amounts of toxin with them (much like a tattoo artist injecting ink under your skin). Mild itching to burning and great amounts of pain may ensue. Remove spicules by soaking the wound in white vinegar for 15 minutes, drying the skin, and using the sticky side of adhesive tape to remove them. Use hydrocortisone cream for the irritation and if the rash worsens seek medical attention. This group includes the hydroids, sea anemones, corals and jellyfishes. The cnidarians all possess tentacles equipped with stinging nematocysts, which are located on the outer layer of the tentacles. The nematocyst is a small in size (rarely exceed 50 microns), venom-filled capsule (see right) containing a hollow coiled thread which, when triggered, is used to inject poison (green area) into the body of its prey. Brushing with a cnidarian triggers many thousand skin injections, the severity of which depends upon the species touched and the individual’s sensitivity. stings should be treated by removing any tentacles with tweezers, and using either a weak ammonia or a weak vinegar solution to denature (break down the proteins) the nematocysts. A paste of unseasoned meat tenderiser (10-15 minutes only) may also help relieve symptoms. Do not rub sand on the wound or rinse with fresh water, it will cause unfired nematocysts to fire. Serious cnidarian stings should have ice packs or anaesthetic administered; the victim be monitored for signs of shock or respiratory distress and evacuated to an emergency care facility. Victims may need to be injected with epinephrine from an allergy kit to prevent suffocation from anaphylactic shock. Milder cases can use oral antihistamines or - Hydroids - Fire coral is a hydroid that can cause a painful skin rash. These common coral-like animals are important in the development of reefs, forming upright, blade-like or branching calcareous growths or encrustation over corals and other objects. The hydroid class also includes the Portuguese man-o’war and many other harmless animals. - Jellyfish - Jellyfish are free swimming, pelagic animals with radial symmetry. They swim by regular contractions of their bell-shaped gelatinous bodies. Like many sea animals they go through seasonal breeding cycles, which means the risk from contact with them can be reduced by respecting local proliferation. While most jellyfish are capable of stinging, only a few are considered a major hazard. Of these the Indo-Pacific box jellyfish, Chitonex, is the most dangerous. Within the UK jellyfish seldom affect divers, but a smaller lion's mane jellyfish can be most distressing. - Corals and Sea Anemones - The class Anthozoa is contains two orders: Alcyonaria, which includes all soft corals, sea ferns, sea pens and sea pansies; and Zoantharia, which include sea anemones and corals. Though often extremely beautiful, corals are often fragile and razor sharp and can inflict severe wounds on persons who brush against them. Most anthozoans are harmless to people but a few have stinging cells dangerous to people and many corals. Touching corals is destructive to the animal and the coral reef as they grow very slowly. Casual contact with coral can cause mild to severe reactions because the sharp coral skeletons abrade or cut the skin and allow the coral mucus and bacteria to enter the wound. Wash thoroughly, treat with antibiotic creams and see a physician if the wound does not begin to heal within a day or Unsegmented animals with a distinct and well-developed head, ventral muscular foot and soft body often contained in a calcareous shell. This large and successful phylum occupies most terrestrial and aquatic habitats, but only the cone shells and the cephalopods have been shown to be harmful to people. - Cone Shells - They have characteristic cone-shaped shells and like the other gastropods, a distinct head, “tentacles” with eyes and a strong fleshy foot. The cone has a siphon tube to sample water (to detect prey), as well as a long proboscis to capture and seize prey. In this family the proboscis is variable in shape and carries a poison tooth or dart used to spear and immobilize small fish and other items of food. The risk of being stung by the cone shell is of particular concern to swimmers and divers, but only of the swimmer or diver picks up a living cone. Cones are found throughout the world in tropical and warm temperate waters, but the only really dangerous cones occur in the Indian and Pacific Oceans. Cones are typically found on sandy bottoms in and around reefs. If a diver is stung, restrict circulation to the affected part of the body with a tourniquet or other wrap (not tight enough to stop blood flow). Loosen bandage for 90 seconds every 10 minutes. Or place a pressure bandage directly over the wound. Monitor for signs of shock or cardiac or respiratory arrest. Seek medical attention - Cephalopods - Few marine creatures have received greater attention from fiction writers than has the octopus. The result is that this remarkable, shy and intelligent creature is greatly overrated as a hazard to swimmers. This so-called “demon of the depths” is generally small and retiring in habit and certainly does not deserve its reputation. The only octopus species regularly fatal to humans are the blue-ringed and blue-spotted octopus found on the reefs of Australia and other Indo-Pacific tropical reefs. All octopus are poisonous to some extent and will bite if threatened, although they generally will swim away from a diver. Susceptibility to the toxins is dependent upon individual reaction, and pain and neurological symptoms may occur. If an octopus bites you, wash the wound with soap and water. Hot water may provide relief from the toxin. Seek medical attention if symptoms do not improve. If a blue-ringed octopus bites you, place a pressure bandage over the wound or the entire limb. Prevent limb from moving by splinting it. Be prepared to provide breathing assistance if the victim goes into respiratory arrest and seek medical attention immediately. Segmented worms, or annelids, are organisms that have a long body, which is usually segmented. They are generally found under rocks or rumaging around during the day. Each segment has two bristle-like tufts of setae and in some species these setae can sting. Other species have strong jaws, which can inflict a painful bite. The bristle worm’s hollow bristles are reported to be venomous. Stings may result in intense skin swelling, with a burning sensation or numbness. The bristles can penetrate thin gloves, so these worms should be handled carefully or, more appropriately, not at all. Remove setae with tape and soak the wound in white vinegar, dilute ammonia, hot water, or a paste of unseasoned meat tenderiser for 10-15 minutes. Use topical steroids for inflammation. The echinoderms are a very large group of marine invertebrates, characterized by radial symmetry as adults, often with a pentamerous (five-rayed) body form. Only the families Acanthasteridae, whose members feed on coral colonies and have 12 to 18 arms or rays with large pointed spines, are serious hazards to swimmers and then only if the swimmers touch or step on the sea star. Injury from their spines will swell and become numb. The victim may experience swollen lymph glands and brief muscular paralysis. The victim may also become nauseous. Treat a crown of thorns wound by immersing the wound in hot water (110-114 ° F or 43.3 – 45 C) for 30-90 minutes. Remove spines if present, use topical pain relievers, and seek medical attention for further treatment or if an infection develops. - Sea Urchins - Are common in all seas and are found at all depths. They can be covered with sharp spines that are hazardous to swimmers in shallow reef areas. Diadema antillarum is the common black urchin, the long spines of Diadema are capable of easily penetrating wetsuits and gloves. They are found under reef ledges during the day and come out to feed at night. Other tropical urchins in the Pacific (genus Tripneustes) inject toxin with defensive structures called pedicellariae. In the northern Gulf of Mexico the short-spined urchins Lytichinus variegatus (red) and Arbacia (black) are the most commonly found urchins. All urchins are harmless if the diver does not touch, step, or kneel on them. Other relatives of urchins such as the sand dollar, sea biscuit and heart urchin are not harmful to divers. Urchin wounds should be cleaned and, if painful, soaked in hot water. Do not attempt to remove the spines that break off under the skin. - Sea Cucumbers - Are common in all tropical seas at most depths. They are sluggish creatures that when provoked can eviscerate their sticky intestines leaving the unsuspecting diver with a mess on their hands. They are otherwise harmless. Fish are the most diverse group of vertebrates in the world, ranging in habitat from high mountains and hot thermal springs to the deepest ocean depth. With over 27,000 species, it is not surprising that fish have evolved numerous defensive mechanisms that are potentially dangerous to swimmers. Over 1,000 species of fish are either poisonous to eat or venomous. Most poisonous fish inject poison through spines and then only when deliberately handled or provoked. - Stingrays - Of the many species of rays, the most bothersome to swimmers and divers are the stingrays. There are thousands of wounds from stingrays each year. Stingrays are very common in shallow water, particularly during the summer when they breed and are more active. When walking in the surf, in the shallows, and especially on shallow grass flats, stepping on a stingray may result in a painful sting in the foot or lower leg. Stingrays are not aggressive and only use their defensive sting as a reaction to being threatened. When stepped upon, the ray will lash upwards with its tail. Attached to the base of the tail is a serrated, grooved, spine that can penetrate the skin (usually the foot or calf) of the offender. The spines are barbed and difficult to remove. The spine also carries a toxic epidermis in its groove that produces quite a lot of pain. If a stingray stings you immerse the wound in water as hot as you can stand for 15 minutes at a time to alleviate the pain. Hot towels will also help if the wound cannot be easily immersed. If the spine is well imbedded do not try to remove it and seek medical attention. If you care for the wound yourself, make sure that the wound is thoroughly washed with soap and water and that a general antibiotic cream is applied after drying the wound. If signs of infection appear seek medical attention. Avoid stepping on stingrays by shuffling your feet when you walk in shallow water. Scorpion fish (family Scorpaenidae) are among the most widespread of venomous fishes and second to stingrays in cases of envenomation. They introduce toxins into wounds when using their defensive spines. Spines are located on dorsal and pectoral fins. Several hundred species of scorpion fish exist and representatives are found in all seas. The most dangerous scorpion fish are found in tropical waters. Many of these fish are sedentary and lie on the bottom immobile and camouflaged. Venomous scorpion fish have been divided into three main groups on the basis of the structure of their venom organs: Lion fish and zebra fish of the Pterois type (Indo-Pacific and Red Sea); scorpion fish – Scorpaena, etc., widely distributed; and stonefish – Synanceja of the western Pacific and Indian oceans. Divers encounter these camouflaged fish by accidentally touching or kneeling on the fish. Scorpion fish wounds can cause numbness, local paralysis, intense pain, nausea, and in the case of the stone fish even death. Wounds should be immersed in hot water for at least 30 minutes. Wounds to the chest or abdomen require medical attention. Stone fish victims should be watched for signs of weakness, respiratory difficulty or cardiac arrest. - Lion Fish - Lion fish are among the most beautiful and ornate of all coral reef fishes. They are generally found in shallow tropical seas of the Indian and Pacific Oceans and the Red Sea, hovering around crevices or at times swimming gracefully in the open. Frequently seen swimming in pairs, they rarely take avoidance action when approached and are not aggressive. In Guam, these beautiful fish are called Turkey fish. Many injuries are caused by the divers not knowing they are close and placing their hand on them or kneeling on them. When agitated they "fire" their spines into their attacker and the wounds can be excruciatingly painful. Be particularly wary on night dives as the lion fish is more active and may follow the torch lights. Treatment consists of immersing the affected part in the hottest bearable water and get medical attention. - Scorpion Fish - Are found from the intertidal zone to depths of 90 m (300 feet) and for the most part live in bays, along sandy beaches, rocky coastlines and coral reefs. Their camouflage colouring and secretive habit of hiding in crevices, among debris, under rocks or in seaweed make them difficult to see. When removed from the water they erect the spiny dorsal fin and flare the armed gill covers pectoral, pelvic and anal fins. - Stone Fish - Largely shallow water dwellers and are commonly found in tide pools and shallow reef areas of the tropical Western Pacific and Indian Oceans. They habitually lie motionless in coral crevices, under rocks, in holes or buried in the sand or mud. They are very well camouflaged and require extreme agitation to induce movement. Stonefish wounds may require antivenom and can be fatal, so extreme care must be taken with a victim of the stonefish. Watch for cardiac arrhythmia or cardiac arrest and seek immediate medical attention after providing first aid. The Weever Fish a sandy coloured fish that can be found around the UK coast in shallow, warm and sandy waters. It can grow to 10cm long and has 5-7 poisonous spines protruding from its dorsal fin. It frequently lies partially submerged in the sand with its spines exposed. Typically the casualty usually complains of having trodden of something sharp under the water, followed by a severe stinging sensation. At first glance there appears to be no wound, but on closer inspection two pin pricks about 1cm apart are visible with slight reddening around them. Treatment includes heating the area with the hottest water bearable and get medical attention. Venomous snakes are a more widespread hazard in freshwater than in the sea. Avoid all large snakes that appear threatening. Snake bites should be treated by applying a pressure bandage and the victim should remain as inactive as possible. Immediately seek medical attention. - Sea Snakes - There are 50 different species of sea snakes found only in the tropical Indo-Pacific region. All are venomous and capable of inflicting fatal bites, but they are not aggressive and generally do not bite humans unless handled. They may become aggressive during mating season or when guarding their nest. Sea snake bites are serious in only 25% of cases, since the bite is a defensive one and the snake usually injects only a small dose of venom. Symptoms can include general malaise or anxiety, difficulty in speaking or swallowing, vomiting, aching or pain on movement, weakness (progressing within 1-2 hours to an inability to move, beginning in the legs), muscle spasms, droopy eyelids, thirst, shock, and respiratory distress. If a person is bitten, apply a pressure bandage, keep the victim immobile as is possible, and evacuate them to medical facilities. Anti-venom is given only when serious symptoms begin to manifest (e.g., painful muscle Electricity is an important constituent in the metabolic activity of living things. The amount of current is normally so small that it can be detected only by sensitive instruments. Electrical fish posses a specialized organ that discharges electricity through the water at surprisingly high voltages and is used to stun prey. There are about 250 species of fish known to possess specialized electric organs capable of delivering painful electric shock. Of the fish that have electric organs, Electric Eels and Catfish live in freshwater, while Stargazers and Torpedo rays are marine species. Divers are not likely to see an electric eel unless they dive in the Amazon River, but electric rays are found in both the Atlantic and Pacific oceans. - Electric Rays - The electric rays are found in tropical and temperate marine waters. Although most species prefer shallow waters, some members are found at moderately deep depths. Instead of being pointed at the head end with a whip like tail, electric rays are broadly rounded and have a tail that is thicker and flattened from side to side. The electric ray is a slow moving animal and uses its tail to swim slowly. These rays are easy to avoid and are not aggressive. The electric shock is delivered from modified muscles near the front of the body through the skin surface, and the polarity of the electric organ is positive on the dorsal surface and negative on the underside. Divers can avoid obtaining a shock of up to 200 volts (enough to stun a diver) by simply leaving the electric ray alone. - Stargazers - The Stargazers are a small group of carnivorous bottom-dwelling marine fish. They are characterized by having a large cuboid head, an almost vertical mouth with fringed lips and an elongated, conical and compressed body. Their electric organs are said to be modified eye muscles and since they spend a considerable portion of their time buried in the sand or mud with only their eyes and a portion of their mouth protruding, they present a possible menace to intruders. Invertebrates that are poisonous to eat - Molluscs - Throughout the world, mollusc's are eaten in large quantities, especially the bivalve mollusc's, such as oysters, which are considered a gourmet’s delight. Yet problems are encountered with eating mollusc's. This is due to the feeding habits of the bivalves. They filter small particles from the water through extensive gills and then concentrate them in the body. Bivalves, which can thrive in polluted estuarine waters, accumulate all manners of pollutants. Shellfish should only be consumed from safe, tested shellfish grounds. Bivalves can be the source of enteric viruses that cause hepatitis or diarrheic diseases, and can also be the source of bacterial diseases such as cholera, salmonella, and vibrio vulnificus. Bivalves also filter toxic algae from the water and can be the source of a variety of toxic conditions such as paralytic, diarrhetic, or amnesiatic shellfish poisoning. Some of these conditions can cause permanent mental damage or even death, and shellfish should not be harvested when bans related to red tide and other toxic algal blooms are in effect. During these bans even whelks (large marine snails) that feed on bivalves may become toxic and should be avoided. - Marine Arthropods - The phylum Arthropoda (invertebrate animals with jointed legs) is the largest single group in the animal kingdom, having more than 800,000 species. Relatively little is known about the poisonous marine arthropods. However, amnesiatic poisonings have also been found to be possible in some crabs, probably because they consumed bivalves containing algal toxins. Tropical reef crabs may also be suspect. Vertebrates that are Poisonous to Eat While there are many cases of humans suffering gastrointestinal complaints as a result of eating marine fish, in most cases this is traced to secondary contamination of the food. However, there are numerous species in the tropics, which are poisonous. Some tropical reef fish may contain toxins, which prove fatal to humans. The following is a list of ichthyosarcotoxism’s or poisoning resulting from eating fish flesh. - Elasmobranch Poisoning - Caused by eating sharks, rays and some of their relatives (Black tip Reef Shark, Greenland Shark, Seven-gilled and Six-gilled Sharks, Great White Shark and Smooth Hammerhead Shark). - Ciguatera Fish Poisoning - Caused by eating various species of tropical reef fish. The most commonly involved species are barracuda, grouper, snappers, jacks, wrasses, parrot fish, and surgeon fish. Toxins come from certain algae eaten by the fish or by predators eating fish that have consumed such algae. No method outside of the laboratory exists to determine whether or not a fish is toxic, and its occurrence within a species of fish is unpredictable, although oversize fish are more likely to be toxic than smaller ones. Cooking does not destroy the toxin. Internal organs are more toxic than the flesh. Signs and symptoms include numbness and tingling of lips and tongue, abdominal cramps, nausea and vomiting, diarrhoea, weakness, reversal of thermal sensation (hot and cold reversal), muscle/joint aching, nervousness, metallic taste in mouth, visual disturbances, extreme fatigue, muscle paralysis, convulsions, headache, dizziness, and heart failure. No definitive first aid exists. If symptoms occur early (<4 hours) induce vomiting. Seek medical attention for all suspected cases. Mannitol in IV form is the treatment of choice for severe neurological or cardiac symptoms. Other symptoms can be treated with antihistamines and anti nausea medication. Death is rare. Be prepared to administer Cardio Pulmonary Resuscitation (CPR). - Scombroid fish poisoning - Some scombroid (mostly dark fleshed) fish i.e., tuna, bonito, mackerel, bluefish that have been exposed to sunlight or have been left standing at room temperature for several hours may develop a toxin that is a type of histamine. Such fish may have a peppery or sharp taste or may be completely normal in taste, colour, or appearance. Within a few minutes after eating the fish, symptoms of this type of poisoning develop. Symptoms usually clear within 8-12 hours, although fatigue and headache may persist for a few days. Signs and symptoms are nausea, vomiting, flushing of face, severe headache, diarrhoea, abdominal pain, dizziness, massive red welts, severe itching, severe dehydration (thirst), shortness of breath, bronchospasm, cardiac palpitation, inability to swallow, and shock. The victim should seek medical aid as soon as possible. Watch for respiratory distress. It may be necessary to use an epinephrine injection to prevent respiratory blockage. Oral antihistamines may work in less severe cases and will also limit itching. - Tetrodotoxin “Puffer” Fish Poisoning - Certain puffers (blowfish, porcupinefish, globefish, swellfish) contain tetrodotoxin, one of the most potent poisons found in nature. These fish are prepared as a delicacy called “fugu” in Japan by specially trained and licensed chefs. The toxin is found in the entire fish with the greatest concentration in the liver, intestines, reproductive organs, and skin. After eating the fish, the victim may experience symptoms in as little as ten minutes or as much as a few hours. Because these toxins can be fatal to humans, it is wise to avoid eating puffers. Signs and symptoms of tetrodotoxin poisoning include: numbness and tingling around the mouth, light headedness, drooling, sweating, abdominal pain, vomiting, diarrhoea, weakness, difficulty walking, paralysis, difficulty breathing, and collapse. Treatment includes transport to a hospital. Monitor victim continuously and prepare to assist breathing. There is no antidote and the victim will need sophisticated medical treatment. - Turtle Poisoning (chelonitoxication) - Caused by eating the flesh of certain marine turtles (Green Sea Turtle, Hawksbill Turtle, Leatherback Turtle).
HHO Effects on an Engineby Richard Rowe "Brown's Gas," oxyhydrogen or HHO; whatever you want to call it, this gas burns with as much controversy as heat. HHO generators use electric current passing through water to split the water molecule into its component parts, oxygen and hydrogen. While the science of its production is sound, HHO's effects on an engine remain a hotly debated topic. Engines require air and fuel to make power. Almost all engines burn some sort of hydrocarbon, in which the active ingredient is hydrogen. This hydrogen combines with oxygen to produce an explosion, which forces the piston down and turns the engine. So, the logic behind introducing a pure mix of oxygen and hydrogen is sound, and should lead to ultra-efficient combustion and the cleanest possible emissions. HHO generators use electricity produced by the engine's alternator to make their gas, which is where the problem lay. Whether you want to call it "perpetual motion" or the more scientific "over-unity," getting more energy out of a substance than it took to make it is physically impossible. The best case scenario from a physics standpoint is that the HHO generator makes just enough gas to offset the power required to make it. When factoring efficiency losses through the alternator, HHO generator and the engine itself, you're more likely to see a drop in fuel economy than a rise. That's the theory, anyway. As a Supplement True, the combination of HHO gas and hydrogen cannot (in and of itself) increase fuel economy, but there is another possible avenue for efficiency increases while using the gas. HHO itself contains 1/3 oxygen by volume and 2/3 hydrogen (which has an octane rating of 130). Those two factors alone can help the engine to more efficiently burn the gasoline it normally ingests. More gasoline burned means less going out of the tailpipe. Some engines can sense combustion efficiency by "listening" to the sound of the combustion event in the cylinder; if such an engine were to detect the presence of a high-octane fuel and oxidizer, it might well increase ignition timing to capitalize on it. Increasing ignition timing makes horsepower, which can increase fuel economy. The oxygen generated by HHO systems could theoretically reduce emissions for the same reason they may improve fuel economy. More oxygen in the cylinders more thoroughly combust the fuel, so there are fewer unburned hydrocarbons exiting the tailpipe. Another aspect to consider is that the HHO actually displaces some of the natural air that would otherwise enter the cylinder. Earth's atmosphere contains 78 percent nitrogen, which converts into harmful nitrogen oxides (NOx) emissions in the cylinder. Less normal air means less nitrogen in the cylinder, meaning there is a very real possibility that HHO generators could help to reduce NOx (nitrogen oxide) emissions. HHO generators have no known harmful effects on healthy engines. HHO generator manufacturers often assert that oxyhydrogen helps clean carbon deposits from the engine's valves, but that's unlikely since HHO gas has no solvent effect whatsoever. Large amounts of quick-burning HHO in the cylinder itself may help to burn off some oil residue from the piston and cylinder head, but this premise hasn't been tested thoroughly enough to confirm. - photo_camera ocean image by Yulia Volodina from Fotolia.com
collision-energy increase is a factor of four if two balls of the same speed collide head-on as opposed to one of them being at rest. However, because of relativity and the conservation of momentum, the effective energy of the collision of particles aimed at each other is far greater. At the Fermilab Tevatron, collisions have been made between 900-GeV protons and 900-GeV antiprotons. Achieving the same collision energy with a stationary target would require an accelerator with a circumference about 2,000 times as large as Fermilab's, or about 8,000 miles! There are different types of colliders operating today that are important for particle physics. The relatively large mass of protons and antiprotons makes it more efficient to accelerate them to high energies than to accelerate electrons or positrons. However, in the collisions, it is their constituents—quarks and gluons—that interact. Since many subatomic constituents make up the proton and antiproton, no single one carries the full energy of the accelerated particle. For example, in proton-proton collisions, the effective collision energy is about a factor of 10 lower than the full energy of the beam. By increasing the intensity of the beams, it is sometimes possible to study higher-energy processes. In collisions between electrons and positrons, the energy of collision is the full energy to which the particles are raised (since electrons and positrons appear to have no substructure). Such collisions cleanly probe the electromagnetic and weak interactions: They do not create the extraneous debris characteristic of proton collisions and are easier to interpret. Finally, because an electron lacks substructure and behaves in a point-like way, it is a useful probe for exploring the structure of the proton. An electron-proton collider provides information about the structure of a proton that is not available from a proton collider and provides an opportunity to search for hypothesized objects that combine both quark and lepton characteristics. The variety of phenomena that particle physicists have uncovered and are studying has been surveyed in this chapter. Although these phenomena occur at the smallest distance scales, what is observed has relevance in understanding the physics of forces that govern the atom, the energetic processes in cores of stars, and even the structure of the universe. The collisions of high-energy particles have been shown to reveal new and important structure. These collisions re-create the conditions of the universe just after its birth. The laws that are discovered have existed for all time and everywhere in the universe. A small number of forces have been discovered, all of which could arise from a single one. The particles on which these forces act have a mysterious structure; the lighter ones make up our everyday world, whereas the role of the next two generations still represents a major puzzle. The following chapter presents the theoretical framework in which these phenomena are currently understood.
Southeastern United States: The geographic area of the southeastern region of the United States in general or when the specific state or states are not included. The states usually included in this region are Alabama, Arkansas, Florida, Georgia, Louisiana, Mississippi, North Carolina, South Carolina, West Virginia, and Virginia.Southwestern United States: The geographic area of the southwestern region of the United States. The states usually included in this region are Arizona, California, Colorado, Nevada, New Mexico, Texas, and Utah.Population Surveillance: Ongoing scrutiny of a population (general population, study population, target population, etc.), generally using methods distinguished by their practicability, uniformity, and frequently their rapidity, rather than by complete accuracy.Midwestern United States: The geographic area of the midwestern region of the United States in general or when the specific state or states are not indicated. The states usually included in this region are Illinois, Indiana, Iowa, Kansas, Kentucky, Michigan, Minnesota, Missouri, Nebraska, Ohio, Oklahoma, North Dakota, South Dakota and Wisconsin.Northwestern United States: The geographic area of the northwestern region of the United States. The states usually included in this region are Idaho, Montana, Oregon, Washington, and Wyoming.Incidence: The number of new cases of a given disease during a given period in a specified population. It also is used for the rate at which new events occur in a defined population. It is differentiated from PREVALENCE, which refers to all cases, new or old, in the population at a given time.Hispanic Americans: Persons living in the United States of Mexican (MEXICAN AMERICANS), Puerto Rican, Cuban, Central or South American, or other Spanish culture or origin. The concept does not include Brazilian Americans or Portuguese Americans.Prevalence: The total number of cases of a given disease in a specified population at a designated time. It is differentiated from INCIDENCE, which refers to the number of new cases in the population at a given time.European Continental Ancestry Group: Individuals whose ancestral origins are in the continent of Europe.Risk Factors: An aspect of personal behavior or lifestyle, environmental exposure, or inborn or inherited characteristic, which, on the basis of epidemiologic evidence, is known to be associated with a health-related condition considered important to prevent.Ethnic Groups: A group of people with a common cultural heritage that sets them apart from others in a variety of social relationships.Centers for Disease Control and Prevention (U.S.): An agency of the UNITED STATES PUBLIC HEALTH SERVICE that conducts and supports programs for the prevention and control of disease and provides consultation and assistance to health departments and other countries.Continental Population Groups: Groups of individuals whose putative ancestry is from native continental populations based on similarities in physical appearance.United States Food and Drug Administration: An agency of the PUBLIC HEALTH SERVICE concerned with the overall planning, promoting, and administering of programs pertaining to maintaining standards of quality of foods, drugs, therapeutic devices, etc.Canada: The largest country in North America, comprising 10 provinces and three territories. Its capital is Ottawa.Emigration and Immigration: The process of leaving one's country to establish residence in a foreign country.African Americans: Persons living in the United States having origins in any of the black groups of Africa.Disease Outbreaks: Sudden increase in the incidence of a disease. The concept includes EPIDEMICS and PANDEMICS.Age Distribution: The frequency of different ages or age groups in a given population. The distribution may refer to either how many or what proportion of the group. The population is usually patients with a specific disease but the concept is not restricted to humans and is not restricted to medicine.Age Factors: Age as a constituent element or influence contributing to the production of a result. It may be applicable to the cause or the effect of a circumstance. It is used with human or animal concepts but should be differentiated from AGING, a physiological process, and TIME FACTORS which refers only to the passage of time.Infant, Newborn: An infant during the first month after birth.Health Surveys: A systematic collection of factual data pertaining to health and disease in a human population within a given geographic area.Data Collection: Systematic gathering of data for a particular purpose from various sources, including questionnaires, interviews, observation, existing records, and electronic devices. The process is usually preliminary to statistical analysis of the data.Socioeconomic Factors: Social and economic factors that characterize the individual or group within the social structure.United States Virgin Islands: A group of islands in the Lesser Antilles in the West Indies, the three main islands being St. Croix, St. Thomas, and St. John. The capital is Charlotte Amalie. Before 1917 the U.S. Virgin Islands were held by the Danish and called the Danish West Indies but the name was changed when the United States acquired them by purchase.African Continental Ancestry Group: Individuals whose ancestral origins are in the continent of Africa.MexicoHistory, 20th Century: Time period from 1901 through 2000 of the common era.United States Department of Agriculture: A cabinet department in the Executive Branch of the United States Government concerned with improving and maintaining farm income and developing and expanding markets for agricultural products. Through inspection and grading services it safeguards and insures standards of quality in food supply and production.New England: The geographic area of New England in general and when the specific state or states are not indicated. States usually included in this region are Maine, New Hampshire, Vermont, Massachusetts, Connecticut, and Rhode Island.Travel: Aspects of health and disease related to travel.Sex Factors: Maleness or femaleness as a constituent element or influence contributing to the production of a result. It may be applicable to the cause or effect of a circumstance. It is used with human or animal concepts but should be differentiated from SEX CHARACTERISTICS, anatomical or physiological manifestations of sex, and from SEX DISTRIBUTION, the number of males and females in given circumstances.National Center for Health Statistics (U.S.): A center in the PUBLIC HEALTH SERVICE which is primarily concerned with the collection, analysis, and dissemination of health statistics on vital events and health activities to reflect the health status of people, health needs, and health resources.Sex Distribution: The number of males and females in a given population. The distribution may refer to how many men or women or what proportion of either in the group. The population is usually patients with a specific disease but the concept is not restricted to humans and is not restricted to medicine.Nutrition Surveys: A systematic collection of factual data pertaining to the nutritional status of a human population within a given geographic area. Data from these surveys are used in preparing NUTRITION ASSESSMENTS.Puerto Rico: An island in the Greater Antilles in the West Indies. Its capital is San Juan. It is a self-governing commonwealth in union with the United States. It was discovered by Columbus in 1493 but no colonization was attempted until 1508. It belonged to Spain until ceded to the United States in 1898. It became a commonwealth with autonomy in internal affairs in 1952. Columbus named the island San Juan for St. John's Day, the Monday he arrived, and the bay Puerto Rico, rich harbor. The island became Puerto Rico officially in 1932. (From Webster's New Geographical Dictionary, 1988, p987 & Room, Brewer's Dictionary of Names, 1992, p436)Cross-Cultural Comparison: Comparison of various psychological, sociological, or cultural factors in order to assess the similarities or diversities occurring in two or more different cultures or societies.United States Dept. of Health and Human Services: A cabinet department in the Executive Branch of the United States Government concerned with administering those agencies and offices having programs pertaining to health and human services.Health Care Surveys: Statistical measures of utilization and other aspects of the provision of health care services including hospitalization and ambulatory care.Cross-Sectional Studies: Studies in which the presence or absence of disease or other health-related variables are determined in each member of the study population or in a representative sample at one particular time. This contrasts with LONGITUDINAL STUDIES which are followed over a period of time.Asian Americans: Persons living in the United States having origins in any of the original peoples of the Far East, Southeast Asia, or the Indian subcontinent.Public Health: Branch of medicine concerned with the prevention and control of disease and disability, and the promotion of physical and mental health of the population on the international, national, state, or municipal level.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Mortality: All deaths reported in a given population.Vital Statistics: Used for general articles concerning statistics of births, deaths, marriages, etc.SEER Program: A cancer registry mandated under the National Cancer Act of 1971 to operate and maintain a population-based cancer reporting system, reporting periodically estimates of cancer incidence and mortality in the United States. The Surveillance, Epidemiology, and End Results (SEER) Program is a continuing project of the National Cancer Institute of the National Institutes of Health. Among its goals, in addition to assembling and reporting cancer statistics, are the monitoring of annual cancer incident trends and the promoting of studies designed to identify factors amenable to cancer control interventions. (From National Cancer Institute, NIH Publication No. 91-3074, October 1990)Retrospective Studies: Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.Seasons: Divisions of the year according to some regularly recurrent phenomena usually astronomical or climatic. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Health Services Accessibility: The degree to which individuals are inhibited or facilitated in their ability to gain entry to and to receive care and services from the health care system. Factors influencing this ability include geographic, architectural, transportational, and financial considerations, among others.Emigrants and Immigrants: People who leave their place of residence in one country and settle in a different country.Cohort Studies: Studies in which subsets of a defined population are identified. These groups may or may not be exposed to factors hypothesized to influence the probability of the occurrence of a particular disease or other outcome. Cohorts are defined populations which, as a whole, are followed in an attempt to determine distinguishing subgroup characteristics.Health Status Disparities: Variation in rates of disease occurrence and disabilities between population groups defined by socioeconomic characteristics such as age, ethnicity, economic resources, or gender and populations identified geographically or similar measures.Mid-Atlantic Region: A geographical area of the United States comprising the District of Columbia, Delaware, Maryland, New Jersey, New York, and Pennsylvania.Logistic Models: Statistical models which describe the relationship between a qualitative dependent variable (that is, one which can take only certain discrete values, such as the presence or absence of a disease) and an independent variable. A common application is in epidemiology for estimating an individual's risk (probability of a disease) as a function of a given risk factor.Questionnaires: Predetermined sets of questions used to collect data - clinical data, social status, occupational group, etc. The term is often applied to a self-completed survey instrument.American Medical Association: Professional society representing the field of medicine.Hospitalization: The confinement of a patient in a hospital.Pregnancy: The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.Geography: The science dealing with the earth and its life, especially the description of land, sea, and air and the distribution of plant and animal life, including humanity and human industries with reference to the mutual relations of these elements. (From Webster, 3d ed)Acculturation: Process of cultural change in which one group or members of a group assimilate various cultural patterns from another.Foodborne Diseases: Acute illnesses, usually affecting the GASTROINTESTINAL TRACT, brought on by consuming contaminated food or beverages. Most of these diseases are infectious, caused by a variety of bacteria, viruses, or parasites that can be foodborne. Sometimes the diseases are caused by harmful toxins from the microbes or other chemicals present in the food. Especially in the latter case, the condition is often called food poisoning.Mexican Americans: Persons living in the United States of Mexican descent.Wounds and Injuries: Damage inflicted on the body as the direct or indirect result of an external force, with or without disruption of structural continuity.Mass Screening: Organized periodic procedures performed on large groups of people for the purpose of detecting disease.Demography: Statistical interpretation and description of a population with reference to distribution, composition, or structure.EuropeBehavioral Risk Factor Surveillance System: Telephone surveys are conducted to monitor prevalence of the major behavioral risks among adults associated with premature MORBIDITY and MORTALITY. The data collected is in regard to actual behaviors, rather than on attitudes or knowledge. The Centers for Disease Control and Prevention (CDC) established the Behavioral Risk Factor Surveillance System (BRFSS) in 1984.Risk Assessment: The qualitative or quantitative estimation of the likelihood of adverse effects that may result from exposure to specified health hazards or from the absence of beneficial influences. (Last, Dictionary of Epidemiology, 1988)Medicare: Federal program, created by Public Law 89-97, Title XVIII-Health Insurance for the Aged, a 1965 amendment to the Social Security Act, that provides health insurance benefits to persons over the age of 65 and others eligible for Social Security benefits. It consists of two separate but coordinated programs: hospital insurance (MEDICARE PART A) and supplementary medical insurance (MEDICARE PART B). (Hospital Administration Terminology, AHA, 2d ed and A Discursive Dictionary of Health Care, US House of Representatives, 1976)Health Care Costs: The actual costs of providing services related to the delivery of health care, including the costs of procedures, therapies, and medications. It is differentiated from HEALTH EXPENDITURES, which refers to the amount of money paid for the services, and from fees, which refers to the amount charged, regardless of cost.TexasInternationality: The quality or state of relating to or affecting two or more nations. (After Merriam-Webster Collegiate Dictionary, 10th ed)Smoking: Inhaling and exhaling the smoke of burning TOBACCO.Healthcare Disparities: Differences in access to or availability of medical facilities and services.Licensure: The legal authority or formal permission from authorities to carry on certain activities which by law or regulation require such permission. It may be applied to licensure of institutions as well as individuals.Insurance, Health: Insurance providing coverage of medical, surgical, or hospital care in general or for which there is no specific heading.Registries: The systems and processes involved in the establishment, support, management, and operation of registers, e.g., disease registers.Databases, Factual: Extensive collections, reputedly complete, of facts and data garnered from material of a specialized subject area and made available for analysis and application. The collection can be automated by various contemporary methods for retrieval. The concept should be differentiated from DATABASES, BIBLIOGRAPHIC which is restricted to collections of bibliographic references.HIV Infections: Includes the spectrum of human immunodeficiency virus infections that range from asymptomatic seropositivity, thru AIDS-related complex (ARC), to acquired immunodeficiency syndrome (AIDS).Minority Groups: A subgroup having special characteristics within a larger group, often bound together by special ties which distinguish it from the larger group.Influenza, Human: An acute viral infection in humans involving the respiratory tract. It is marked by inflammation of the NASAL MUCOSA; the PHARYNX; and conjunctiva, and by headache and severe, often generalized, myalgia.WisconsinIncome: Revenues or receipts accruing from business enterprise, labor, or invested capital.Health Expenditures: The amounts spent by individuals, groups, nations, or private or public organizations for total health care and/or its various components. These amounts may or may not be equivalent to the actual costs (HEALTH CARE COSTS) and may or may not be shared among the patient, insurers, and/or employers.Vaccination: Administration of vaccines to stimulate the host's immune response. This includes any preparation intended for active immunological prophylaxis.New MexicoFloridaPhylogeny: The relationships of groups of organisms as reflected by their genetic makeup.Multivariate Analysis: A set of techniques used when variation in several variables has to be studied simultaneously. In statistics, multivariate analysis is interpreted as any analytic method that allows simultaneous study of two or more dependent variables.History, 21st Century: Time period from 2001 through 2100 of the common era.Health Policy: Decisions, usually developed by government policymakers, for determining present and future objectives pertaining to the health care system.ArizonaCause of Death: Factors which produce cessation of all vital bodily functions. They can be analyzed from an epidemiologic viewpoint.GeorgiaLife Expectancy: Based on known statistical data, the number of years which any person of a given age may reasonably expected to live.Residence Characteristics: Elements of residence that characterize a population. They are applicable in determining need for and utilization of health services.National Health Insurance, United StatesCommerce: The interchange of goods or commodities, especially on a large scale, between different countries or between populations within the same country. It includes trade (the buying, selling, or exchanging of commodities, whether wholesale or retail) and business (the purchase and sale of goods to make a profit). (From Random House Unabridged Dictionary, 2d ed, p411, p2005 & p283)Public Policy: A course or method of action selected, usually by a government, from among alternatives to guide and determine present and future decisions.North AmericaUnited States Occupational Safety and Health Administration: An office in the Department of Labor responsible for developing and establishing occupational safety and health standards.Treatment Outcome: Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.Substance-Related Disorders: Disorders related to substance abuse.United States Public Health Service: A constituent organization of the DEPARTMENT OF HEALTH AND HUMAN SERVICES concerned with protecting and improving the health of the nation.Military Personnel: Persons including soldiers involved with the armed forces.Birth Rate: The number of births in a given population per year or other unit of time.Neoplasms: New abnormal growth of tissue. Malignant neoplasms show a greater degree of anaplasia and have the properties of invasion and metastasis, compared to benign neoplasms.New YorkEnvironmental Exposure: The exposure to potentially harmful chemical, physical, or biological agents in the environment or to environmental factors that may include ionizing radiation, pathogenic organisms, or toxic chemicals.State Government: The level of governmental organization and function below that of the national or country-wide government.Healthy People Programs: Healthy People Programs are a set of health objectives to be used by governments, communities, professional organizations, and others to help develop programs to improve health. It builds on initiatives pursued over the past two decades beginning with the 1979 Surgeon General's Report, Healthy People, Healthy People 2000: National Health Promotion and Disease Prevention Objectives, and Healthy People 2010. These established national health objectives and served as the basis for the development of state and community plans. These are administered by the Office of Disease Prevention and Health Promotion (ODPHP). Similar programs are conducted by other national governments.Foreign Medical Graduates: Physicians who hold degrees from medical schools in countries other than the ones in which they practice.Educational Status: Educational attainment or level of education of individuals.Insurance Coverage: Generally refers to the amount of protection available and the kind of loss which would be paid for under an insurance contract with an insurer. (Slee & Slee, Health Care Terms, 2d ed)Physicians: Individuals licensed to practice medicine.Indians, North American: Individual members of North American ethnic groups with ancient historic ancestral origins in Asia.Physician's Practice Patterns: Patterns of practice related to diagnosis and treatment as especially influenced by cost of the service requested and provided.Homicide: The killing of one person by another.Poverty: A situation in which the level of living of an individual, family, or group is below the standard of the community. It is often related to a specific income level.Odds Ratio: The ratio of two odds. The exposure-odds ratio for case control data is the ratio of the odds in favor of exposure among cases to the odds in favor of exposure among noncases. The disease-odds ratio for a cohort or cross section is the ratio of the odds in favor of disease among the exposed to the odds in favor of disease among the unexposed. The prevalence-odds ratio refers to an odds ratio derived cross-sectionally from studies of prevalent cases.Delivery of Health Care: The concept concerned with all aspects of providing and distributing health services to a patient population.WashingtonForecasting: The prediction or projection of the nature of future problems or existing conditions based upon the extrapolation or interpretation of existing scientific data or by the application of scientific methodology.Regression Analysis: Procedures for finding the mathematical function which best describes the relationship between a dependent variable and one or more independent variables. In linear regression (see LINEAR MODELS) the relationship is constrained to be a straight line and LEAST-SQUARES ANALYSIS is used to determine the best fit. In logistic regression (see LOGISTIC MODELS) the dependent variable is qualitative rather than continuously variable and LIKELIHOOD FUNCTIONS are used to find the best relationship. In multiple regression, the dependent variable is considered to depend on more than a single independent variable.United States Environmental Protection Agency: An agency in the Executive Branch of the Federal Government. It was created as an independent regulatory agency responsible for the implementation of federal laws designed to protect the environment. Its mission is to protect human health and the ENVIRONMENT.AlaskaRefugees: Persons fleeing to a place of safety, especially those who flee to a foreign country or power to escape danger or persecution in their own country or habitual residence because of race, religion, or political belief. (Webster, 3d ed)Cost of Illness: The personal cost of acute or chronic disease. The cost to the patient may be an economic, social, or psychological cost or personal loss to self, family, or immediate community. The cost of illness may be reflected in absenteeism, productivity, response to treatment, peace of mind, or QUALITY OF LIFE. It differs from HEALTH CARE COSTS, meaning the societal cost of providing services related to the delivery of health care, rather than personal impact on individuals.Communicable Diseases, Emerging: Infectious diseases that are novel in their outbreak ranges (geographic and host) or transmission mode.Death Certificates: Official records of individual deaths including the cause of death certified by a physician, and any other required identifying information.Serotyping: Process of determining and distinguishing species of bacteria or viruses based on antigens they share.Accidents, Traffic: Accidents on streets, roads, and highways involving drivers, passengers, pedestrians, or vehicles. Traffic accidents refer to AUTOMOBILES (passenger cars, buses, and trucks), BICYCLING, and MOTORCYCLES but not OFF-ROAD MOTOR VEHICLES; RAILROADS nor snowmobiles.History, 19th Century: Time period from 1801 through 1900 of the common era.Cost-Benefit Analysis: A method of comparing the cost of a program with its expected benefits in dollars (or other currency). The benefit-to-cost ratio is a measure of total return expected per unit of money spent. This analysis generally excludes consideration of factors that are not measured ultimately in economic terms. Cost effectiveness compares alternative ways to achieve a specific set of results.Risk: The probability that an event will occur. It encompasses a variety of measures of the probability of a generally unfavorable outcome.Anti-Bacterial Agents: Substances that reduce the growth or reproduction of BACTERIA.ColoradoHealth Behavior: Behaviors expressed by individuals to protect, maintain or promote their health status. For example, proper diet, and appropriate exercise are activities perceived to influence health status. Life style is closely associated with health behavior and factors influencing life style are socioeconomic, educational, and cultural.Politics: Activities concerned with governmental policies, functions, etc.Health Status: The level of health of the individual, group, or population as subjectively assessed by the individual or by more objective measures.Firearms: Small-arms weapons, including handguns, pistols, revolvers, rifles, shotguns, etc.Genotype: The genetic constitution of the individual, comprising the ALLELES present at each GENETIC LOCUS.Australia: The smallest continent and an independent country, comprising six states and two territories. Its capital is Canberra.Health Knowledge, Attitudes, Practice: Knowledge, attitudes, and associated behaviors which pertain to health-related topics such as PATHOLOGIC PROCESSES or diseases, their prevention, and treatment. This term refers to non-health workers and health workers (HEALTH PERSONNEL).Longitudinal Studies: Studies in which variables relating to an individual or group of individuals are assessed over a period of time.Drug Approval: Process that is gone through in order for a drug to receive approval by a government regulatory agency. This includes any required pre-clinical or clinical testing, review, submission, and evaluation of the applications and test results, and post-marketing surveillance of the drug.Waiting Lists: Prospective patient listings for appointments or treatments.PhilippinesWest Nile Fever: A mosquito-borne viral illness caused by the WEST NILE VIRUS, a FLAVIVIRUS and endemic to regions of Africa, Asia, and Europe. Common clinical features include HEADACHE; FEVER; maculopapular rash; gastrointestinal symptoms; and lymphadenopathy. MENINGITIS; ENCEPHALITIS; and MYELITIS may also occur. The disease may occasionally be fatal or leave survivors with residual neurologic deficits. (From Joynt, Clinical Neurology, 1996, Ch26, p13; Lancet 1998 Sep 5;352(9130):767-71)Government Agencies: Administrative units of government responsible for policy making and management of governmental activities.Legislation, Food: Laws and regulations concerned with industrial processing and marketing of foods.Developed Countries: Countries that have reached a level of economic achievement through an increase of production, per capita income and consumption, and utilization of natural and human resources.Censuses: Enumerations of populations usually recording identities of all persons in every place of residence with age or date of birth, sex, occupation, national origin, language, marital status, income, relation to head of household, information on the dwelling place, education, literacy, health-related data (e.g., permanent disability), etc. The census or "numbering of the people" is mentioned several times in the Old Testament. Among the Romans, censuses were intimately connected with the enumeration of troops before and after battle and probably a military necessity. (From Last, A Dictionary of Epidemiology, 3d ed; Garrison, An Introduction to the History of Medicine, 4th ed, p66, p119)Confidence Intervals: A range of values for a variable of interest, e.g., a rate, constructed so that this range has a specified probability of including the true value of the variable.Obesity: A status with BODY WEIGHT that is grossly above the acceptable or desirable weight, usually due to accumulation of excess FATS in the body. The standards may vary with age, sex, genetic or cultural background. In the BODY MASS INDEX, a BMI greater than 30.0 kg/m2 is considered obese, and a BMI greater than 40.0 kg/m2 is considered morbidly obese (MORBID OBESITY).World Health: The concept pertaining to the health status of inhabitants of the world.Military Medicine: The practice of medicine as applied to special circumstances associated with military operations.Disease Reservoirs: Animate or inanimate sources which normally harbor disease-causing organisms and thus serve as potential sources of disease outbreaks. Reservoirs are distinguished from vectors (DISEASE VECTORS) and carriers, which are agents of disease transmission rather than continuing sources of potential disease outbreaks.Costs and Cost Analysis: Absolute, comparative, or differential costs pertaining to services, institutions, resources, etc., or the analysis and study of these costs.Urban Population: The inhabitants of a city or town, including metropolitan areas and suburban areas.Sequence Analysis, DNA: A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.Accidents, Occupational: Unforeseen occurrences, especially injuries in the course of work-related activities.Ambulatory Care: Health care services provided to patients on an ambulatory basis, rather than by admission to a hospital or other health care facility. The services may be a part of a hospital, augmenting its inpatient services, or may be provided at a free-standing facility.Drug and Narcotic Control: Control of drug and narcotic use by international agreement, or by institutional systems for handling prescribed drugs. This includes regulations concerned with the manufacturing, dispensing, approval (DRUG APPROVAL), and marketing of drugs.JapanHospitals: Institutions with an organized medical staff which provide medical care to patients.Molecular Epidemiology: The application of molecular biology to the answering of epidemiological questions. The examination of patterns of changes in DNA to implicate particular carcinogens and the use of molecular markers to predict which individuals are at highest risk for a disease are common examples.International Cooperation: The interaction of persons or groups of persons representing various nations in the pursuit of a common goal or interest.Prospective Studies: Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.Health Manpower: The availability of HEALTH PERSONNEL. It includes the demand and recruitment of both professional and allied health personnel, their present and future supply and distribution, and their assignment and utilization.New York CityNew JerseyCluster Analysis: A set of statistical methods used to group variables or observations into strongly inter-related subgroups. In epidemiology, it may be used to analyze a closely grouped series of events or cases of disease or other health-related phenomenon with well-defined distribution patterns in relation to time or place or both.Foreign Professional Personnel: Persons who have acquired academic or specialized training in countries other than that in which they are working. The concept excludes physicians for which FOREIGN MEDICAL GRADUATES is the likely heading.Consumer Product SafetyDiet: Regular course of eating and drinking adopted by a person or animal.Disease Notification: Notification or reporting by a physician or other health care provider of the occurrence of specified contagious diseases such as tuberculosis and HIV infections to designated public health agencies. The United States system of reporting notifiable diseases evolved from the Quarantine Act of 1878, which authorized the US Public Health Service to collect morbidity data on cholera, smallpox, and yellow fever; each state in the US has its own list of notifiable diseases and depends largely on reporting by the individual health care provider. (From Segen, Dictionary of Modern Medicine, 1992)ConnecticutLegislation as Topic: The enactment of laws and ordinances and their regulation by official organs of a nation, state, or other legislative organization. It refers also to health-related laws and regulations in general or for which there is no specific heading.Tissue and Organ Procurement: The administrative procedures involved with acquiring TISSUES or organs for TRANSPLANTATION through various programs, systems, or organizations. These procedures include obtaining consent from TISSUE DONORS and arranging for transportation of donated tissues and organs, after TISSUE HARVESTING, to HOSPITALS for processing and transplantation.Agriculture: The science, art or practice of cultivating soil, producing crops, and raising livestock.Pharmacopoeias as Topic: Authoritative treatises on drugs and preparations, their description, formulation, analytic composition, physical constants, main chemical properties used in identification, standards for strength, purity, and dosage, chemical tests for determining identity and purity, etc. They are usually published under governmental jurisdiction (e.g., USP, the United States Pharmacopoeia; BP, British Pharmacopoeia; P. Helv., the Swiss Pharmacopoeia). They differ from FORMULARIES in that they are far more complete: formularies tend to be mere listings of formulas and prescriptions.Interviews as Topic: Conversations with an individual or individuals held in order to obtain information about their background and other personal biographical data, their attitudes and opinions, etc. It includes school admission or job interviews.Comorbidity: The presence of co-existing or additional diseases with reference to an initial diagnosis or with reference to the index condition that is the subject of study. Comorbidity may affect the ability of affected individuals to function and also their survival; it may be used as a prognostic indicator for length of hospital stay, cost factors, and outcome or survival.Epidemiological Monitoring: Collection, analysis, and interpretation of data about the frequency, distribution, and consequences of disease or health conditions, for use in the planning, implementing, and evaluating public health programs.Risk-Taking: Undertaking a task involving a challenge for achievement or a desirable goal in which there is a lack of certainty or a fear of failure. It may also include the exhibiting of certain behaviors whose outcomes may present a risk to the individual or to those associated with him or her.Chronic Disease: Diseases which have one or more of the following characteristics: they are permanent, leave residual disability, are caused by nonreversible pathological alteration, require special training of the patient for rehabilitation, or may be expected to require a long period of supervision, observation, or care. (Dictionary of Health Services Management, 2d ed)MontanaCentral AmericaGovernment Regulation: Exercise of governmental authority to control conduct.Guidelines as Topic: A systematic statement of policy rules or principles. Guidelines may be developed by government agencies at any level, institutions, professional societies, governing boards, or by convening expert panels. The text may be cursive or in outline form but is generally a comprehensive guide to problems and approaches in any field of activity. For guidelines in the field of health care and clinical medicine, PRACTICE GUIDELINES AS TOPIC is available.Managed Care Programs: Health insurance plans intended to reduce unnecessary health care costs through a variety of mechanisms, including: economic incentives for physicians and patients to select less costly forms of care; programs for reviewing the medical necessity of specific services; increased beneficiary cost sharing; controls on inpatient admissions and lengths of stay; the establishment of cost-sharing incentives for outpatient surgery; selective contracting with health care providers; and the intensive management of high-cost health care cases. The programs may be provided in a variety of settings, such as HEALTH MAINTENANCE ORGANIZATIONS and PREFERRED PROVIDER ORGANIZATIONS.Genetic Variation: Genotypic differences observed among individuals in a population.Sexual Behavior: Sexual activities of humans.Hospital Bed Capacity: The number of beds which a hospital has been designed and constructed to contain. It may also refer to the number of beds set up and staffed for use.Infant Mortality: Postnatal deaths from BIRTH to 365 days after birth in a given population. Postneonatal mortality represents deaths between 28 days and 365 days after birth (as defined by National Center for Health Statistics). Neonatal mortality represents deaths from birth to 27 days after birth.Health Care Reform: Innovation and improvement of the health care system by reappraisal, amendment of services, and removal of faults and abuses in providing and distributing health services to patients. It includes a re-alignment of health services and health insurance to maximum demographic elements (the unemployed, indigent, uninsured, elderly, inner cities, rural areas) with reference to coverage, hospitalization, pricing and cost containment, insurers' and employers' costs, pre-existing medical conditions, prescribed drugs, equipment, and services.West Nile virus: A species of FLAVIVIRUS, one of the Japanese encephalitis virus group (ENCEPHALITIS VIRUSES, JAPANESE). It can infect birds and mammals. In humans, it is seen most frequently in Africa, Asia, and Europe presenting as a silent infection or undifferentiated fever (WEST NILE FEVER). The virus appeared in North America for the first time in 1999. It is transmitted mainly by CULEX spp mosquitoes which feed primarily on birds, but it can also be carried by the Asian Tiger mosquito, AEDES albopictus, which feeds mainly on mammals.IllinoisHealth Services Needs and Demand: Health services required by a population or community as well as the health services that the population or community is able and willing to pay for.Follow-Up Studies: Studies in which individuals or populations are followed to assess the outcome of exposures, procedures, or effects of a characteristic, e.g., occurrence of disease. Pinguicula lutea: Pinguicula lutea, commonly known as the yellow butterwort, is a species of warm-temperate carnivorous plant in the Lentibulariaceae family. It grows in savannas and sandy bog areas of the Southeastern United States.Southwestern United States: The Southwestern United States (also known as the American Southwest) is the United States portion of the Southwest (which is situated in both the United States and Mexico). It is a region of the United States defined in different ways by different sources.Proportional reporting ratio: The proportional reporting ratio (PRR) is a statistic that is used to summarize the extent to which a particular adverse event is reported for individuals taking a specific drug, compared to the frequency at which the same adverse event is reported for patients taking some other drug (or who are taking any drug in a specified class of drugs). The PRR will typically be calculated using a surveillance database in which reports of adverse events from a variety of drugs are recorded.Speedway LLC: Speedway LLC is the operator of a chain of combination gas stations and convenience stores in the Midwestern United States operating under its namesake brand and along the East Coast of the United States under the Hess and WilcoHess brands. Speedway LLC is a wholly owned subsidiary of the Marathon Petroleum Corporation and is the largest chain in central Ohio.Phyllodoce empetriformis: Phyllodoce empetriformis, the pink mountain-heather or pink mountain-heath, is found in mountainous regions of western North America in the Northwestern United States and Western Canada. Its southern range includes the Klamath Range in northern California and Oregon.Incidence (epidemiology): Incidence is a measure of the probability of occurrence of a given medical condition in a population within a specified period of time. Although sometimes loosely expressed simply as the number of new cases during some time period, it is better expressed as a proportion or a rate with a denominator.QRISK: QRISK2 (the most recent version of QRISK) is a prediction algorithm for cardiovascular disease (CVD) that uses traditional risk factors (age, systolic blood pressure, smoking status and ratio of total serum cholesterol to high-density lipoprotein cholesterol) together with body mass index, ethnicity, measures of deprivation, family history, chronic kidney disease, rheumatoid arthritis, atrial fibrillation, diabetes mellitus, and antihypertensive treatment.The Complete Stevie Wonder: The Complete Stevie Wonder is a digital compilation featuring the work of Stevie Wonder. Released a week before the physical release of A Time to Love, the set comprises almost all of Wonder's officially released material, including single mixes, extended versions, remixes, and Workout Stevie Workout, a 1963 album which was shelved and replaced by With A Song In My Heart.IontocaineCanadian Organ Replacement Registry: The Canadian Organ Replacement Registry CORR is a health organisation was started by Canadian nephrologists and kidney transplant surgeons in 1985 in order to develop the care of patients with renal failure. In the early 1990s data on liver and heart transplantation were added to the registry.List of countries that regulate the immigration of felons: This is a list of countries that regulate the immigration of felons.African-American family structure: The family structure of African-Americans has long been a matter of national public policy interest.Moynihan's War on Poverty report A 1965 report by Daniel Patrick Moynihan, known as The Moynihan Report, examined the link between black poverty and family structure.National Outbreak Reporting System: ==The National Outbreak Reporting System (NORS)==Age adjustment: In epidemiology and demography, age adjustment, also called age standardization, is a technique used to allow populations to be compared when the age profiles of the populations are quite different.List of rivers of the United States Virgin Islands: List of rivers and streams in the United States Virgin Islands (U.S.Old Portal de Mercaderes (Mexico City): Old Portal de Mercaderes in the historic center of Mexico City was and is the west side of the main plaza (otherwise known as the "Zócalo"). This side of the plaza has been occupied by commercial structures since the Spanish Conquest of Mexico in 1521.The Flash ChroniclesFoundation Course for Agricultural Research ServiceNew England's Dark Day: New England's Dark Day refers to an event that occurred on May 19, 1780, when an unusual darkening of the day sky was observed over the New England states and parts of Canada. The primary cause of the event is believed to have been a combination of smoke from forest fires, a thick fog, and cloud cover.Carte Jaune: The Carte Jaune or Yellow Card is an international certificate of vaccination (ICV). It is issued by the World Health Organisation.San Juan River (Vancouver Island): The San Juan River is a river on southern Vancouver Island, British Columbia, Canada, draining into the Pacific Ocean at Port San Juan, the harbour for Port Renfrew,BCGNIS entry "San Juan River" which is at the limit of the Strait of Juan de Fuca, which lies south and southeast of the river. Its name is derived from that or Port San Juan, which is also the namesake of San Juan Ridge, which lies on the south side of the river's final W-E course.Public Health Act: Public Health Act is a stock short title used in the United Kingdom for legislation relating to public health.Temporal analysis of products: Temporal Analysis of Products (TAP), (TAP-2), (TAP-3) is an experimental technique for studyingMortality rate: Mortality rate, or death rate, is a measure of the number of deaths (in general, or due to a specific cause) in a particular population, scaled to the size of that population, per unit of time. Mortality rate is typically expressed in units of deaths per 1,000 individuals per year; thus, a mortality rate of 9.Vital statistics (government records): Vital statistics are statistics on live births, deaths, fetal deaths, marriages and divorces. The most common way of collecting information on these events is through civil registration, an administrative system used by governments to record vital events which occur in their populations (see Box 1).Four Seasons Baltimore and Residences: Four Seasons Hotel Baltimore is currently a 22 story highrise hotel complex building which opened on November 14, 2011. The building's construction began back in 2007 and went through several changes.Inequality within immigrant families in the United States: Inequality within immigrant families refers to instances in which members of the same family have differing access to resources. Much literature focuses on inequality between families, but inequality often exists within families as well.Cumberland Farms: Cumberland Farms is a regional chain of convenience stores based in Framingham, Massachusetts, and operating primarily in New England, portions of the Mid-Atlantic region of the United States, and Florida. Cumberland Farms operates roughly 600 retail stores, gas stations, and a support system including petroleum and grocery distribution operations in 11 states, including Connecticut, Delaware, Florida, Massachusetts, Maine, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, and Vermont.Closed-ended question: A closed-ended question is a question format that limits respondents with a list of answer choices from which they must choose to answer the question.Dillman D.Charles Alfred Tyrrell: Charles Alfred Tyrrell(1843–1918) was a promoter of medical devices, most notably an enema appliance. He was also author of tracts promoting the use of his device for colon cleansing as therapy for detoxification pursuant to a theory of auto-intoxication.Prenatal nutrition: Nutrition and weight management before and during :pregnancy has a profound effect on the development of infants. This is a rather critical time for healthy fetal development as infants rely heavily on maternal stores and nutrient for optimal growth and health outcome later in life.Health geography: Health geography is the application of geographical information, perspectives, and methods to the study of health, disease, and health care.List of foodborne illness outbreaks: This is a list of foodborne illness outbreaks. A foodborne illness may be from an infectious disease, heavy metals, chemical contamination, or from natural toxins, such as those found in poisonous mushrooms.National Center for Injury Prevention and Control: The U.S.Cancer screeningGA²LENGlobal Risks Report: The Global Risks Report is an annual study published by the World Economic Forum ahead of the Forum’s Annual Meeting in Davos, Switzerland. Based on the work of the Global Risk Network, the report describes changes occurring in the global risks landscape from year to year and identifies the global risks that could play a critical role in the upcoming year.Themis MedicareUniversity of Texas Health Science Center at HoustonCriticisms of globalization: Criticism of globalization is skepticism of the claimed benefits of globalization. Many of these views are held by the anti-globalization movement.Contraceptive mandate (United States): A contraceptive mandate is a state or federal regulation or law that requires health insurers, or employers that provide their employees with health insurance, to cover some contraceptive costs in their health insurance plans. In 1978, the U.Disease registry: Disease or patient registries are collections of secondary data related to patients with a specific diagnosis, condition, or procedure, and they play an important role in post marketing surveillance of pharmaceuticals. Registries are different from indexes in that they contain more extensive data.Management of HIV/AIDS: The management of HIV/AIDS normally includes the use of multiple antiretroviral drugs in an attempt to control HIV infection. There are several classes of antiretroviral agents that act on different stages of the HIV life-cycle.Ethnic groups in the United Kingdom: People from various ethnic groups reside in the United Kingdom. Migration from Northern Europe has been happening for millennia, with other groups such as British Jews also well established.Influenza A virus subtype H1N1: Influenza A (H1N1) virus is the subtype of influenza A virus that was the most common cause of human influenza (flu) in 2009, and is associated with the 1918 outbreak known as the Spanish Flu.Wisconsin Senate, District 4: The 4th District of the Wisconsin Senate is located in Southern Wisconsin, and is composed of parts of Milwaukee County.District MapCircular flow of income: The circular flow of income or circular flow is a model of the economy in which the major exchanges are represented as flows of money, goods and services, etc. between economic agents.VaccinationAlbuquerque IsotopesMiami-Dade County Corrections and Rehabilitation Department: The Miami-Dade County Corrections and Rehabilitation Department is an agency of the government of Miami-Dade County, Florida. It has its headquarters in the Gladeview census-designated place in an unincorporated area.Branching order of bacterial phyla (Gupta, 2001): There are several models of the Branching order of bacterial phyla, one of these was proposed in 2001 by Gupta based on conserved indels or protein, termed "protein signatures", an alternative approach to molecular phylogeny. Some problematic exceptions and conflicts are present to these conserved indels, however, they are in agreement with several groupings of classes and phyla.Health policy: Health policy can be defined as the "decisions, plans, and actions that are undertaken to achieve specific health care goals within a society."World Health Organization.Arizona State Prison Complex – Perryville: Arizona State Prison Complex – Perryville is one of 13 prison facilities operated by the Arizona Department of Corrections (ADC)."Arizona State Prison Complex- Perryville.Emory University Hospital: Emory University Hospital is a 587-bed facility in Atlanta, Georgia, specializing in the care of the acutely ill adults. Emory University Hospital is staffed exclusively by Emory University School of Medicine faculty who also are members of The Emory Clinic.List of U.S. states by life expectancy: This article presents a list of United States states sorted by their life expectancy at birth and by race/ethnicity in every state where the population of that racial or ethnic group is sufficiently large for robust estimates. The data is taken from the Measure of America's third national human development report, The Measure of America 2013–2014 width="25%" align="center" |Neighbourhood: A neighbourhood (Commonwealth English), or neighborhood (American English), is a geographically localised community within a larger city, town, suburb or rural area. Neighbourhoods are often social communities with considerable face-to-face interaction among members.List of largest employers: ==Largest public and private and Government employers in the world==Australian referendum, 1913 (Trade and Commerce): The Constitution Alteration (Trade and Commerce) 1912 was an Australian referendum held in the 1913 referendums which sought to alter the Australian Constitution to extend Commonwealth legislative power in respect to trade and commerce.American Medical Student Association (1/58711) Racing problems in the U.S.A. The major problems of racing in the United States at the present time are caused by too much racing. This has led to too few horses and small fields. Consequently many owners and trainers are trying to enter their horses too frequently and to race them when they are not really fit to run. The desire to race horses as frequently as possible has led to constant pressure from horsemen through their organizations for so called "permissive medication". Started in the state of Colorado approximately ten years ago this has grown until finally there are only a few states, notably New York and New Jersey that have resisted the pressure. The drug that gave the opening wedge to permissive medication was phenylbutazone, but this in many states has led to the inclusion of other drugs including analgesics and drugs that veterinarians claim are needed for therapeutic purposes. Some states have endeavoured to control phenylbutazone medication by quantitation and while lower limits cause little difficulty, maximum allowable limits have caused problems and are not practical. While there has been no publicity to my knowledge about frusemide (furosemide, lasix) the abuse of this drug for so called "bleeders" is an example that may seriously interfere with drug detection in urine and its use should be confined to proven "bleeders" (i.e. horses suffering from epistaxis). Pre-race blood testing began roughly ten years ago at the harness tracks and has been resisted by our flat tracks rather successfully up to the present time. The blood testing methods and those used by the same laboratories in post-race urine testing is inadequate and will not detect many illegal drugs. (+info) (2/58711) Myths, models and mitigation of resistance to pesticides. Resistance to pesticides in arthropod pests is a significant economic, ecological and public health problem. Although extensive research has been conducted on diverse aspects of pesticide resistance and we have learned a great deal during the past 50 years, to some degree the discussion about 'resistance management' has been based on 'myths'. One myth involves the belief that we can manage resistance. I will maintain that we can only attempt to mitigate resistance because resistance is a natural evolutionary response to environmental stresses. As such, resistance will remain an ongoing dilemma in pest management and we can only delay the onset of resistance to pesticides. 'Resistance management' models and tactics have been much discussed but have been tested and deployed in practical pest management programmes with only limited success. Yet the myth persists that better models will provide a 'solution' to the problem. The reality is that success in using mitigation models is limited because these models are applied to inappropriate situations in which the critical genetic, ecological, biological or logistic assumptions cannot be met. It is difficult to predict in advance which model is appropriate to a particular situation; if the model assumptions cannot be met, applying the model sometimes can increase the rate of resistance development rather than slow it down. Are there any solutions? I believe we already have one. Unfortunately, it is not a simple or easy one to deploy. It involves employing effective agronomic practices to develop and maintain a healthy crop, monitoring pest densities, evaluating economic injury levels so that pesticides are applied only when necessary, deploying and conserving biological control agents, using host-plant resistance, cultural controls of the pest, biorational pest controls, and genetic control methods. As a part of a truly multi-tactic strategy, it is crucial to evaluate the effect of pesticides on natural enemies in order to preserve them in the cropping system. Sometimes, pesticide-resistant natural enemies are effective components of this resistance mitigation programme. Another name for this resistance mitigation model is integrated pest management (IPM). This complex model was outlined in some detail nearly 40 years ago by V. M. Stern and colleagues. To deploy the IPM resistance mitigation model, we must admit that pest management and resistance mitigation programmes are not sustainable if based on a single-tactic strategy. Delaying resistance, whether to traditional pesticides or to transgenic plants containing toxin genes from Bacillus thuringiensis, will require that we develop multi-tactic pest management programmes that incorporate all appropriate pest management approaches. Because pesticides are limited resources, and their loss can result in significant social and economic costs, they should be reserved for situations where they are truly needed--as tools to subdue an unexpected pest population outbreak. Effective multi-tactic IPM programmes delay resistance (= mitigation) because the number and rates of pesticide applications will be reduced. (+info) (3/58711) Bioterrorism alleging use of anthrax and interim guidelines for management--United States, 1998. From October 30 through December 23, 1998, CDC received reports of a series of bioterroristic threats of anthrax exposure. Letters alleged to contain anthrax were sent to health clinics on October 30, 1998, in Indiana, Kentucky, and Tennessee. During December 17-23 in California, a letter alleged to contain anthrax was sent to a private business, and three telephone threats of anthrax contamination of ventilation systems were made to private and public buildings. All threats were hoaxes and are under investigation by the Federal Bureau of Investigation (FBI) and local law enforcement officials. The public health implications of these threats were investigated to assist in developing national public health guidelines for responding to bioterrorism. This report summarizes the findings of these investigations and provides interim guidance for public health authorities on bioterrorism related to anthrax. (+info) (4/58711) Physician advice and individual behaviors about cardiovascular disease risk reduction--seven states and Puerto Rico, 1997. Cardiovascular disease (CVD) (e.g., heart disease and stroke) is the leading cause of death in the United States and accounted for 959,227 deaths in 1996. Strategies to reduce the risk for heart disease and stroke include lifestyle changes (e.g., eating fewer high-fat and high-cholesterol foods) and increasing physical activity. The U.S. Preventive Services Task Force and the American Heart Association (AHA) recommend that, as part of a preventive health examination, all primary-care providers counsel their patients about a healthy diet and regular physical activity. AHA also recommends low-dose aspirin use as a secondary preventive measure among persons with existing CVD. To determine the prevalence of physician counseling about cardiovascular health and changes in individual behaviors, CDC analyzed data from the Behavioral Risk Factor Surveillance System (BRFSS) for seven states and Puerto Rico. This report summarizes the results of that analysis, which indicate a lower prevalence of counseling and behavior change among persons without than with a history of heart disease or stroke. (+info) (5/58711) Cardiovascular disease in insulin dependent diabetes mellitus: similar rates but different risk factors in the US compared with Europe. BACKGROUND: Cardiovascular disease (CVD) in insulin dependent diabetes mellitus (IDDM) has been linked to renal disease. However, little is known concerning international variation in the correlations with hyperglycaemia and standard CVD risk factors. METHODS: A cross-sectional comparison was made of prevalence rates and risk factor associations in two large studies of IDDM subjects: the Pittsburgh Epidemiology of Diabetes Complications Study (EDC) and the EURODIAB IDDM Complications Study from 31 centres in Europe. Subgroups of each were chosen to be comparable by age and duration of diabetes. The EDC population comprises 286 men (mean duration 20.1 years) and 281 women (mean duration 19.9 years); EURODIAB 608 men (mean duration 18.1 years) and 607 women (mean duration 18.9 years). The mean age of both populations was 28 years. Cardiovascular disease was defined by a past medical history of myocardial infarction, angina, and/or the Minnesota ECG codes (1.1-1.3, 4.1-4.3, 5.1-5.3, 7.1). RESULTS: Overall prevalence of CVD was similar in the two populations (i.e. men 8.6% versus 8.0%, women 7.4% versus 8.5%, EURODIAB versus EDC respectively), although EDC women had a higher prevalence of angina (3.9% versus 0.5%, P < 0.001). Multivariate modelling suggests that glycaemic control (HbA1c) is not related to CVD in men. Age and high density lipoprotein cholesterol predict CVD in EURODIAB, while triglycerides and hypertension predict CVD in EDC. For women in both populations, age and hypertension (or renal disease) are independent predictors. HbA1c is also an independent predictor-inversely in EURODIAB women (P < 0.008) and positively in EDC women (P = 0.03). Renal disease was more strongly linked to CVD in EDC than in EURODIAB. CONCLUSIONS: Despite a similar prevalence of CVD, risk factor associations appear to differ in the two study populations. Glycaemic control (HbA1c) does not show a consistent or strong relationship to CVD. (+info) (6/58711) Novel endotheliotropic herpesviruses fatal for Asian and African elephants. A highly fatal hemorrhagic disease has been identified in 10 young Asian and African elephants at North American zoos. In the affected animals there was ultrastructural evidence for herpesvirus-like particles in endothelial cells of the heart, liver, and tongue. Consensus primer polymerase chain reaction combined with sequencing yielded molecular evidence that confirmed the presence of two novel but related herpesviruses associated with the disease, one in Asian elephants and another in African elephants. Otherwise healthy African elephants with external herpetic lesions yielded herpesvirus sequences identical to that found in Asian elephants with endothelial disease. This finding suggests that the Asian elephant deaths were caused by cross-species infection with a herpesvirus that is naturally latent in, but normally not lethal to, African elephants. A reciprocal relationship may exist for the African elephant disease. (+info) (7/58711) Prevalence of peripheral arterial disease and associated risk factors in American Indians: the Strong Heart Study. Studies of peripheral arterial disease (PAD) in minority populations provide researchers with an opportunity to evaluate PAD risk factors and disease severity under different types of conditions. Examination 1 of the Strong Heart Study (1989-1992) provided data on the prevalence of PAD and its risk factors in a sample of American Indians. Participants (N = 4,549) represented 13 tribes located in three geographically diverse centers in the Dakotas, Oklahoma, and Arizona. Participants in this epidemiologic study were aged 45-74 years; 60% were women. Using the single criterion of an ankle brachial index less than 0.9 to define PAD, the prevalence of PAD was approximately 5.3% across centers, with women having slightly higher rates than men. Factors significantly associated with PAD in univariate analyses for both men and women included age, systolic blood pressure, hemoglobin A1c level, albuminuria, fibrinogen level, fasting glucose level, prevalence of diabetes mellitus, and duration of diabetes. Multiple logistic regression analyses were used to predict PAD for women and men combined. Age, systolic blood pressure, current cigarette smoking, pack-years of smoking, albuminuria (micro- and macro-), low density lipoprotein cholesterol level, and fibrinogen level were significantly positively associated with PAD. Current alcohol consumption was significantly negatively associated with PAD. In American Indians, the association of albuminuria with PAD may equal or exceed the association of cigarette smoking with PAD. (+info) (8/58711) Reliability of information on physical activity and other chronic disease risk factors among US women aged 40 years or older. Data on chronic disease risk behaviors and related variables, including barriers to and attitudes toward physical activity, are lacking for women of some racial/ethnic groups. A test-retest study was conducted from July 1996 through June 1997 among US women (n = 199) aged 40 years or more who were white, black, American Indian/Alaska Native, or Hispanic. The sample was selected and interviews were conducted using a modified version of the methods of the Behavioral Risk Factor Surveillance System. For behavioral risk factors such as physical inactivity, smoking, and low fruit and vegetable consumption, group prevalences were generally similar between interviews 1 and 2. However, kappa values for selected physical activity variables ranged from 0.26 to 0.51 and tended to be lower for black women. Discordance was low for variables on cigarette smoking and exposure to environmental tobacco smoke (kappa = 0.64-0.92). Discordance was high (kappa = 0.33) for low consumption of fruits and vegetables. Additional variables for barriers to and access to exercise ranged widely across racial/ethnic groups and in terms of measures of agreement. These methods illustrate an efficient way to sample and assess the reliability of data collected from women of racial/ethnic minority groups. (+info)
“Children can achieve the full potential of their humanness only through direct, active, personal communication with natural phenomena”-Makiguchi This lesson was designed with educating for sustainability in mind. Although the content includes language connected with the country of Belize, where the lesson was designed to be taught, you can easily modify the lesson so it is meaningful in any country you live in. Just be sure to change the language to meet the needs of your learners! Enjoy 🙂 THE MANY ROLES OF TREES Enduring Understandings: Organisms must share resources to meet the needs of living things equally, across places and generations. -The learners will describe the many roles of trees. -The learners will experience the importance of trees through observation and exploration. Time: 60-90 minutes (depending on class size) - “A Tree is Nice” by Janice May Udry - Large Anchor Chart - Nature Journals (handmade with recycled paper bags/scrap paper OR regular journals) - Large Outdoor Area - Scrap paper - Gather the students to a comfortable area. Show your students the cover page of the book, “A Tree is Nice” by Janice May Udry. - Ask your students, “Why are trees important?” Record their ideas (words & pictures) on the large anchor chart and leave their ideas up in front of the room. - Hand your students a small sheet of scrap paper. Put a few containers of crayons on the ground. Ask your students to draw a picture of a tree. Draw a large tree on the anchor chart. Discuss & label the parts of the tree. Ask the students what a tree starts out as, and how it gets so big. You may want to make a connection to all living things. You can ask your students, “Do all living things grow?” - After students draw their pictures, encourage them to share. Discuss with students the types of trees they drew. Prompting questions include: Which trees do we have in Belize? Which trees have you seen outside of Belize? Why would trees look different in different places? - Read, “A Tree is Nice” by Janice May Udry - During the read-aloud, pause and ask students to describe what the pictures show on each page. Prompting questions include: Are the humans using the trees for the same purposes? Do trees have other purposes? What would happen if we took the tree out of the picture? Would the humans fall? Be comfortable? Have shade? Would the baby be able to nap? Would the cows munch on grass in the comfortable shade? - When you are finished reading the story, discuss the many “roles” the tree played in the book. Ask the students to share their favorite activities to do with trees. Allow students sufficient time to share. Brain Break (Sing 3-5 times with movements) “I’m a Little Tree” (Tune of “I’m a Little Teapot”) I’m a little tree, short and strong (students squat down and make muscles) Here are my roots and here is the ground (students point to their feet) I need water (students sprinkle fingers from head to toes) Good Soil (students jump twice) And lots of sun (students put their hands up over their heads and connect finger tips) So I can give you oxygen and you can have fun (students point fingers out and give a thumbs up) - When you are finished with the brain break, get students ready to head outside. - Students should bring their nature journals & pencils. - Walk around the schoolyard and observe the diverse trees you see. Ask students prompting questions like: Do all the trees look the same? What do you see in the trees? Does anything make the tree its’ home? Why would a tree be a good home for some animals? What about insects? Do animals live only on the outside of trees? What might we find if we cut the tree in half? Are the trees the same color? Which tree is your favorite? Why? What would happen if we didn’t have any trees in our schoolyard? What do the trees smell, feel, look, and sound like? - Give the students about five minutes to sketch a picture of a tree. - Gather them together in a circle and have them share their sketches. - Give your students 30-45 minutes to play outside AMONGST the trees!!! Extension Ideas—MATH & ART - Prior to the lesson, find out the names of various palm trees outside the classroom. - Choose 3-5 types of palm trees that you find and make a large bar graph. - Discuss the types of trees prior to going outside and draw a picture (or print a picture) to show your students the types of trees in a visual manner. - Explain to the students that you will be taking data (information) about the different types of palm trees outside the classroom. - Ask the students to make predictions about which type of palm tree they will find the most or least. - Head outside on a nature hunt and have the students color in a square every time they find on of the palm trees. Prompting questions include: Which tree did we find the most? The least? Were our predictions accurate/correct? Why? Which tree is the biggest? The smallest? The roughest? The smoothest? What do leaves look like on the trees? Do they remind you of certain shapes? What does the bark look-feel-smell like? Do all the trees have the same role in the environment or are certain trees used for certain things? Coconut trees? What do we use them for? - When you are finished, encourage students to think about something else they could take data on. Ideas may include types of flowers, soil, sticks, stones, animals, etc.
Trees need water. That may sound like a simple and obvious statement, but a new study released last week makes the case for how important the correct amount of water is for trees. Researchers compiled data from 226 forest species at 81 sites worldwide. They found that around 70 percent of the species operate with only a narrow margin of safety when it comes to their water supply. In other words, many of the world’s important forest species are vulnerable to hydraulic failure. That means that virtually all types of forests, even in regions that seem to get plenty of rain today, are vulnerable to increased drought and increased evaporation driven by higher temperatures.
There have been a few attempts at developing 3D printers designed for use by children, but is this a wise thing to do? At first, you’d think it would definitely be a good idea. Consider some of the positive effects this would have: - Children would become accustomed to the idea of creating things, which they may carry forward into adulthood, becoming an entrepreneur perhaps, or at least being more self-sufficient - Children could learn 3D modeling skills that should provide them with an important creative outlet that may lead to a future career Yes, those are definitely very good things. But there is a darker side to children’s 3D printing that we should consider. Let’s consider some potential drawbacks. Toxicity: Some 3D print materials are actually toxic, having used lead-based colorants, for example. Many 3D printer filaments are not FDA-approved, meaning you shouldn’t be putting them into your mouth, which some children may do. Even if older children were the 3D printer operators, their younger siblings may eat (or attempt to) some prints. Nanoparticles: Most 3D printers, or at least the ones employing heat to melt plastics, emit quantities of nanoparticles. Unknowing parents might install a 3D printer for their child in a room that’s improperly ventilated, leading to an accumulation of airborne nanoparticles. Not good! Mechanicals: 3D printers have moving parts and there are plenty of pinch hazards within a 3D printer. It’s awfully tempting for a curious child, and they may insert fingers or toes into improper places within a running 3D printer, leading to unpleasant surprises. Heat: To melt plastic filament, 3D printers must raise the temperature of their hotend to oven-ready levels. There are often no barriers between this dangerous hotend and your child’s fingers. Damage may occur. Repairs: 3D printers, particularly the less expensive versions, are mechanical machines that tend to break. Often it falls upon the owner to effect the repairs, and even for adults it is frequently beyond their ability to do the required repairs. How can we expect a child to take on this role? Disappointment: Most inexpensive desktop 3D printers have horrifically bad success rates, even for those expert in running them. For novices, failure rates are even higher. In many cases we’ve seen adults abandon their 3D printer because they “couldn’t make it work”. We would expect children to have at least the same success rates, and if so, they may become disillusioned with the idea of attempting to make things themselves. This is in fact the opposite of the original goals above. Instead of providing a child with a 3D printer, we strongly recommend giving them access to one with supervision and guidance. Access could be at a school, club, makerspace or even parentally supervised. If they can see someone safely operating and repairing a 3D printer, they will certainly become more accustomed to making things. Image credit: Wikimedia
1958: The tallest wave ever recorded — splashing nearly 500 feet taller than the Empire State Building — explodes down Lituya Bay in the Gulf of Alaska. Lituya Bay is a T-shaped fjord on the coast of the Alaskan Panhandle, west of Glacier Bay and about 120 miles west-northwest of Juneau. It measures 7 miles long by 2 miles at its widest point and has a narrow mouth (roughly 1,600 feet wide) that makes navigation difficult during high tides. Once inside, however, vessels (mostly fishing boats) find a snug anchorage among the coves lining the shore. Water from three glaciers empties into Lituya Bay, which is over 700 feet deep in places. This topography was a major ingredient in the formation of the tsunami. (Or, more informally, megatsunami, a word used to describe a wave in excess of 100 meters, or 328 feet). The trigger, however, was a massive landslide at the head of Lituya Bay, caused by an earthquake that may have been as powerful as the one that helped destroy San Francisco in 1906. About 40 million cubic yards of rock — some of it falling from a height of 3,000 feet — plunged down the face of Lituya Glacier into Gilbert Inlet at the northern end of the bay. Sudden water displacement created a wave that shot seaward from the land, and that was certainly a factor in what followed. But similar occurrences in Norway, where fjords are plentiful, never produced a wave remotely close to the size of this one. The wave generated at Lituya Bay that night measured an astounding 1,720 feet tall. How a wave could have reached such a height remains speculative, but scientists studying the aftermath observed that a subglacial lake behind Lituya Glacier had dropped 100 feet in depth. The likeliest explanation for that is the missing water broke through fissures caused by the quake and reached the fjord, adding to the pressure. But even with this factor accounted for, geologists don’t believe that alone would have been enough to create such an enormous wave. A precise explanation has never been offered. Incredibly, several eyewitnesses on the bay at the time the tsunami struck, lived to tell the tale. (Two, unfortunately, did not. They were killed when the wave sank their fishing boat near the mouth of the bay.) The wave’s force leveled all the trees and stripped the vegetation along both shorelines — up to 1,720 feet above sea level near the glacier at the head of the fjord (middle left in the photo). At the mouth , La Chaussee Spit and Harbor Point (photo bottom) were completely denuded by the raging tsunami. Nevertheless, the wave quickly ran out of steam as it entered the Gulf of Alaska and soon dissipated, causing no further problems. The 1958 wave was by far the largest to devastate Lituya Bay, but it was only the latest to be documented there by the U.S. Geological Survey. Previous monster waves struck the fjord in 1853, 1874, 1899 and 1936. Photo: Lituya Bay, Alaska Photo credit: D.J. Miller/U.S Geological Survey - July 9, 1955: Scientists Speak Up to End the Madness - July 9, 1993: Yes, They’re the Romanovs, DNA Tests Confirm - Jan. 31, 1958: Explorer I Makes It Official — There’s a Space Race - Jan. 31, 1958: The Earth’s Girdle - Feb. 3, 1958: Silent Spring Seeks Its Voice - July 29, 1958: Ike Inks Space Law, NASA Born in Wake of Russ Moon - Sept. 12, 1958: Kilby Chips In, Integrates Circuit - Oct. 8, 1958: Takes a Licking, but Keeps On Ticking - Dec. 19, 1958: Ike’s Greeting the First Recorded Message From Space - April 18, 1906: Mother Nature 1, San Francisco 0
The seasons, which are caused by the tilt of the Earth’s axis, are the most important periodic fluctuations in climate. But changes in atmospheric and oceanic circulation pat-terns also cause periodic changes in climate on a global scale. The best known is El Niño– Southern Oscillation (ENSO), which originates in the Pacific Ocean but creates effects around the world. Less well known is the North Atlantic Oscillation, which affects the climates of northern Europe and the Maritime Provinces in Canada. Every two to seven years, the El Niño phenomenon causes atmospheric pressure over the western Pacific Ocean to rise. The equatorial ocean currents that usually flow westward reverse themselves, and the normally cold waters off the coasts of Peru and Chile are replaced with warmer water. This prevents cold, nutrient-rich water from welling up, ruining coastal fishing. It typically happens around Christmastime, hence the name El Niño, or the Christ child. Topic: Earth Science Subtopic: Climate/Climate Change Keywords: Climatology, Droughts, El Nino Current, Ocean circulation, Ocean temperature, Ocean-atmosphere interaction, Rain and rainfall, Weather
⋅ P(B | A): probability of event B occurring, given that event A has already occurred. ⋅ recall: P(A and B) = P(A) ⋅ P(B | A) then: P(B | A) = P(A)P(AandB) Probability Tree Diagram Bag A contains 2 red balls and 3 green balls. Bag B contains 1 red ball and 4 green balls. A fair die is rolled: if a 1 or 2 comes up, a ball is randomly selected from Bag A; if a 3, 4, 5, or 6 comes up, a ball is randomly selected from Bag B. Don't just watch, practice makes perfect. We have over 310 practice questions in Statistics for you to master.
From: NASA MODIS Web Posted: Friday, February 8, 2013 Sometimes, a satellite-eye view reveals a beautiful image that imitates art, while also providing data for scientists. Such was the case on January 21, 2013 when the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Aqua satellite flew over Chile and captured this true color image of complex banks of clouds. The combination of motion, color and textures should please cloud-spotters, nephologists, meteorologists and art lovers alike. Because the way clouds look derive from how they are formed, the various types of clouds that overly the South Pacific Ocean, west of Concepcion, Chile, suggest that various temperature, moisture and wind conditions were at work that day. And it’s the wind that has the most visible effect of all. The gentle S – shaped of the mid-level cloud bank clouds suggests the influence of a curving wind pattern, probably set up as wind blows north-west over the tall and ragged peaks of the Andes Mountains. A tighter swirling pattern, which hugs the southern coast, also suggests turbulent flow around an obstruction, such as a mountain. Overlying the swirling bank, a high-level breeze blows more steadily towards the north, creating a thin veil of clouds aligned in parallel streaks (cloud streets). Off the northern coast, the clouds are larger and aligned in groups rather than streets, suggesting more gentle winds in that location. // end //
Will rainforests survive? That was the topic of a debate at the Smithsonian Institution’s National Museum of Natural History. Satellite data and other research has revealed that huge tracts of abandoned tropical forests, which were once logged or farmed, are regrowing. This evidence has prompted a contentious exchange of views and theories among scientists around the world. One camp suggests that the regrowth of rainforests has been overlooked, resulting in the current “biodiversity crisis” argument, which fears that half of the world’s species could be lost in the coming decades, is too pesimistic. However, another school of thought contends that only about half of the plants species originally found in rainforests will return to the areas, and that many animals will not survive the transition. Others warn that the continuing expansion of netoworks of access roads into rainforests will make it easier for poachers and loggers, threatening the existence of tropical species even further. Cristian Samper, director of the National Museum of Natural History, who presided over the debate, said: “By bringing together the world’s most foremost authorities on different aspects of rainforest sicence, we hope to achieve new insights into a situation with potentially profound implications for all species, including ours.” Using a combination of satellite data and field research, estimates suggest that: - ten million square kilometres have been cleared of at least half of their wood cover for human uses, includingtimber and agriculture - five million square kilometres have been selectively logged, often with high-impact methods that leave forests degraded - Of the intact forests remaining, about 275,000 square kilometres – an area bigger than the UK – were felled in five years (between 2000 and 2005) - approximately 350,000 square kilometres (about 2% of original forested areas) are in some stage of regrowth, primarily in South Asia and Latin America. According to Greg Asner from the Carnegie Institution, deforestation was the most profound change underway in tropical rainforests. However, he added, land abandonment was the second most important trend, with the majority of the abandonment occurring in upland areas that offered marginal farming opportunities. Often, the inhabitants departed to pursue better income opportunities in lowlands and cities. He added that regrowth was relatively quick: the forest canopy closed after just 15 years; after 20 years, about half of the original biomass weight had grown back. Joseph Wright, from the Smithsonian Tropical Research Institute, noted that more than 20% of all land within 10 degrees of the equator had acquired protected status, and that the tropics had a percentage of protected land greater than North America, Europe or Japan. He and colleague Helene Muller-Landau asserted in a 2006 study: “Large areas of tropical forest cover will remain in 2030 and beyond. “We believe that the area covered by tropical forest will never fall to the exceedingly low levels that are often predicted.” They added: “Extinction will threaten a smaller proportion of tropical forest species than previously predicted.” Their position was partly based on UN predictions of growing urbanisation and slower population growth. As a result, the abandoned areas will recover and tropical species spared, they contend. But William Laurance, also from the Smithsonian Tropical Research Institute, argued that secondary and degraded forests would sustain only a fraction of existing animal species. He added that birds and mammals were more vulnerable to the altered habitat than insects and other small organisms. Forest destruction in years past was largely the result of land being cleared for small-scale farming, he observed. However, trade globalisation was fostering large-scale industrial agriculture, logging and mining; all of which was accelerating forest destruction. The world was now losing the equivalent of 50 football fields of old-growth forest every minute, he warned. “Rainforest regrowth is indeed occurring in regions but most old growth is destroyed,” he said. “In biodiversity terms, this is akin to a barn door closing after the horses have escaped.” The findings from the debate, and the evidence presented by the speakers, will be published as papers in a special edition of the journal Conservation Biology. Source: Smithsonian press release Filed under: biodiversity, deforestation, illegal logging, research | Tagged: agriculture, carnegie institution, conservation, conservation biology, deforestation, environment, logging, mining, old growth, rainforest, regrowth, Smithsonian Institution, species loss, timber, trees, tropical forest, urbanisation |
This image shows the Cartwheel Galaxy as seen from Hubble Space Telescope |Observation data (J2000 epoch)| |Right ascension||00h 37m 41.1s| |Declination||−33° 42′ 59″| |Redshift||9050 ± 3 km/s| |Distance||500 Mly (150 Mpc)| |Apparent magnitude (V)||15.2| |Type||S pec (Ring)| |Size||~130,000 ly (diameter)| |Apparent size (V)||1′.1 × 0′.9| |Notable features||Ring shape| |MCG-06-02-022a, PGC 2248| The Cartwheel Galaxy (also known as ESO 350-40) is a lenticular galaxy and ring galaxy about 500 million light-years away in the constellation Sculptor. It is an estimated 150,000 light-years diameter, and a mass of about 2.9–4.8 × 109 solar masses; it rotates at 217 km/s. The Cartwheel galaxy shows non-thermal radio and optical spokes, but they are not the same spokes. The galaxy was once a normal spiral galaxy before it apparently underwent a head-on collision with a smaller companion approximately 200 million years ago (i.e., 200 million years prior to the image). When the nearby galaxy passed through the Cartwheel Galaxy, the force of the collision caused a powerful shock wave through the galaxy, like a rock being tossed into a sandbed. Moving at high speed, the shock wave swept up gas and dust, creating a starburst around the galaxy's center portion that were unscathed. This explains the bluish ring around the center, brighter portion. It can be seen that the galaxy is beginning to retake the form of a normal spiral galaxy, with arms spreading out from a central core. Alternatively, a model based on the gravitational Jeans instability of both axisymmetric (radial) and nonaxisymmetric (spiral) small-amplitude gravity perturbations allows an association between growing clumps of matter and the gravitationally unstable axisymmetric and nonaxisymmetric waves which take on the appearance of a ring and spokes. The unusual shape of the Cartwheel Galaxy may be due to a collision with a smaller galaxy such as those in the lower left of the image. The most recent star burst (star formation due to compression waves) has lit up the Cartwheel rim, which has a diameter larger than the Milky Way. Star formation via starburst galaxies, such as the Cartwheel Galaxy, results in the formation of large and extremely luminous stars. When massive stars explode as supernovas, they leave behind neutron stars and black holes. Some of these neutron stars and black holes have nearby companion stars, and become powerful sources of X-rays as they pull matter off their companions (also known as ultra and hyperluminous X-ray sources). The brightest X-ray sources are likely black holes with companion stars, and appear as the white dots that lie along the rim of the X-ray image. The Cartwheel contains an exceptionally large number of these black hole binary X-ray sources, because many massive stars formed in the ring. - "NASA/IPAC Extragalactic Database". Results for Cartwheel Galaxy. Retrieved 2006-11-25. - Moore, Patrick (2000). The Data Book of Astronomy. CRC Press. p. 318. ISBN 0-7503-0620-3. - Amram P, Mendes de Oliveira C, Boulesteix J, Balkowski C (February 1998). "The Hα kinematic of the Cartwheel galaxy". Astron Astrophys. 330: 881–93. Bibcode:1998A&A...330..881A. - Zwicky F (1941). in Theodore van Karman Anniversary volume Contribution to Applied Mechanics and Related Subjects. Pasadena, California: California Institute of Technology. p. 137. - Griv E (Oct 2005). "Origin of the Cartwheel Galaxy: disk instability?". Astrophys. Space Sci. 299 (4): 371–85. Bibcode:2005Ap&SS.299..371G. doi:10.1007/s10509-005-3423-5. - "Amazing Space- Fast Facts: Cartwheel Galaxy". Amazing Space. 2008. Retrieved 2009-07-03. - Mayya YD; et al. (2005). "The Discovery of Spiral Arms in the Starburst Galaxy M82". Ap J. 628 (1): L33. arXiv: . Bibcode:2005ApJ...628L..33M. doi:10.1086/432644. - "Cartwheel Galaxy". College of Southern Nevada. Retrieved 2009-07-03. - Jane Platt (November 1, 2006). "Cartwheel Galaxy Makes Waves in New NASA Image". NASA. Retrieved 2009-05-15. - "The Cartwheel Galaxy - Introduction". Harvard-Smithsonian Center for Astrophysics. January 22, 2009. Retrieved July 29, 2013.
What Is a Phrasal Verb? Phrasal verb is one of those obscure grammar terms that few non-linguists even remember learning. But phrasal verbs are common in everyday English. They can confuse English learners and English speakers just learning formal grammar, but once you learn to spot them, they are simple and interesting. Not a Verb Phrase You might recall what a verb phrase is: a verb consisting of a main verb and one or more auxiliary (or helping) verbs. Examples would include: - Bob is balancing on a llama. - A third eye has emerged on Stan’s forehead. - I have been kidnapped twelve times by aliens. But despite the similarity of the terms, a phrasal verb is different from a verb phrase. Don’t blame me. I didn’t come up with the names. A phrasal verb is a verb that consists of a verb and a particle. Okay, so what’s a particle? Basically, a particle is a word that doesn’t seem to fit neatly into any of the normal parts of speech categories. In the case of a phrasal verb, it almost always looks like a preposition, but functions more like an adverb…but not exactly. Clear as mud, right? Maybe some examples will help. Here are some common phrasal verbs in action: - Will you please look up the word miasma in that Webster’s? - The CIA might be tapping in to this conversation. - I’ll be fine; just go on without me. Observe how these verbs are all constructed: a regular verb (look, tap, get) with a preposition (up, in, on) attached. That’s a phrasal verb. Only the “prepositions” don’t really function like prepositions. Remember that a preposition always shows relationship between two nouns or pronouns. These words don’t do that. If anything, they function like adverbs, modifying the main verb. That’s why they are sometimes called prepositional adverbs, or adverbial particles. But they don’t work like regular adverbs either — at least not in any literal way. For example, when we use the phrasal verb look up, the word up does not indicate direction like it normally does. It doesn’t mean “to look in an upward direction.” It’s an idiomatic use of up — one that isn’t literal, but is intuitively understood by English speakers. Think about these sentences: - Look up at the beautiful blue sky. - Who is tapping in the basement? - Does this gnome figurine go on the shelf? We find the same words together here: look up, tapping in, and go on. But none of these are phrasal verbs. In the first sentence up is used as an adverb, modifying the verb look. We actually are being told to look in the up direction. In the second two sentences, in, and on are serving as regular prepositions, showing relationship and introducing prepositional phrases. A Whole New Word Here’s the key to understanding a phrasal verb: the addition of the particle turns the verb into an entirely different verb. Phrasal verbs are words working as a unit with a distinct meaning. A phrasal verb is not a verb plus an adverb or a verb plus a preposition. It’s a verb all by itself. The verb shut, for example, means “to close.” But shut up does not mean “to shut in an upward direction.” When you add up to shut, you create a whole new verb that means “be quiet.” Voila! A phrasal verb. Phrasal Verb Phrases Now, a phrasal verb can be a part of a verb phrase too: I will be backing out of my obligation. I’ve underlined the whole verb phrase: will be backing out. Will and be are auxiliary verbs and the main verb is the phrasal verb backing out. Don’t Bother Memorizing Lists All this reminds me again why I don’t like the idea of memorizing the prepositions when learning grammar. I wrote before about how sometimes words in the list of prepositions are used as adverbs. Now we see that sometimes they are used as adverbial particles in the formation of phrasal verbs. Grammar is all about figuring out how words and word groups function to create meaning, and because words that look like prepositions aren’t always functioning as prepositions, it only causes confusion with those who’ve memorized the list. There are hundreds, maybe thousands (I haven’t counted) of phrasal verbs in English. Here’s a short list of some of the more common ones: add up to come down with cut back on do away with get along with get away with get back at get around to go out with look down on look forward to look up to You know that thought you have in your head right now? You should leave it as a comment below. For real.
For dung beetles, Milky Way is guiding light Scientists have found that these inch-long creatures use the glowing edge of the galaxy to guide them as they roll their balls of dung across the African landscape. The report, published online Thursday by the journal Current Biology, provides the first documentation of animals using the Milky Way for navigation. Considering that birds, seals and butterflies are known to rely on the stars to find their way around, the study authors noted that using the Milky Way as a compass “might turn out to be widespread in the animal kingdom.” If any bug needs a straight line to follow, it’s the dung beetle. These nocturnal insects make a habit of balling up pieces of animal manure and rolling the spheres away from the larger pile to save for their own use. The balls, which are considerably bigger than the beetles’ bodies, serve as food and even a nesting place for some species. Given the importance of these dung balls, it’s essential that the beetles keep them away from any would-be thieves. Hence the importance of rolling in a straight line: If they take a curvy route, they could mistakenly wind up back where they started, giving other beetles a chance to steal it. “The whole point of moving the ball away is to avoid the competition,” said Keith Philips, a dung beetle expert at Western Kentucky University in Bowling Green, who wasn’t involved in the new study. “Stop wasting energy moving your ball around.” Vision scientist Marie Dacke of Lund University in Sweden, who led the study, had noticed in previous studies that even on moonless nights, dung beetles were able to move their spheres in straight paths. To put the critters’ routing skills to the test, she and her colleagues tracked their insect subjects through a dung-rolling course on a South African game reserve called Stonehenge. The researchers put the beetles and their balls of dung in the center of an arena of sand surrounded by a meter-high wall so nothing on the ground could be used as a point of reference. An overhead camera filmed their paths. The beetles’ performance was telling. On clear nights when the moon and stars were visible, the insects’ trajectories were more or less straight. Even on a moonless night, the beetles were pretty efficient in their dung-rolling as long as the Milky Way was visible. But when the sky was overcast, the insects went every which way but straight. In a second round of experiments, the researchers put the bugs and their dung balls in the center of a wooden platform two meters across and clocked how long it took for them to reach the edge. With the galaxy in sight, their paths led them to the edge of the platform in as little as 40 seconds. But with clouds blocking their view, it took them nearly two minutes. The researchers even taped makeshift cardboard visors to the beetles’ heads, blocking their view of the sky to eliminate all doubt. To no one’s surprise, the beetles wandered aimlessly, showing no sense of direction. Were the dung beetles navigating by the stars or the Milky Way? To find out, the researchers repeated some of their experiments inside a planetarium in Johannesburg. When the beetles labored under a simulated sky lit only by the Milky Way’s glow, the insects and their dung balls reached the edge of the platform in about 50 seconds. When the galaxy was removed and only the sky’s brightest stars were visible, the task took slightly more than a minute. “This clearly shows that the beetles do not orientate to a single bright ‘lodestar,’ but rather to the band of light that represents the Milky Way,” the researchers concluded. The findings have made the scientists wonder about other species. Cricket frogs travel in only two directions on moonless nights, they noted in their study; perhaps they use the Milky Way’s glow for orientation too. Bradley Mullens, an entomologist at the University of California, Riverside, said the research team’s suspicion was probably correct. “I would not be surprised if other nocturnal insects — or maybe other animal groups — might be able to use a diffuse but directional cue such as the Milky Way,” said Mullens, who wasn’t part of Dacke’s team. “Maybe this paper will stimulate more studies of that nature.” Most recent Off the Wire posts Our new comment system is not supported in IE 7. Please upgrade your browser here.
If God spoke a language, it would be mathematics. Ever since the Ancient Greeks started to analyze the world around them, humanity has used numbers to describe the world around them. Mathematics has grown in leaps and bounds to the point where today many theories possess such a level of abstraction that they have little to none practical application. One thing that stays constant is the effect of great thinkers and intellectuals on the development of the field. The following mathematical giants have shaped the study of Mathematics over the centuries. Pythagoras is best know today for his Pythagorean Theorem, or a-squared plus b-squared equals c squared. None of his writings remain; however, it is known he made advances in music, philosophy, and astronomy, in addition to mathematics. In the later part of his life, he moved to Croton in Southern Italy and founded a religious group known as the Pythagoreans. The sect believed in the sacredness of numbers and forbid the consumption of meat, among other oddities for the time. During Ancient Greece, they were most known for establishing a new way of life. Euclid of Alexandria lived around 300 B.C. during the reign of Ptolemy I. Famous for creating Euclidean geometry, Euclid wrote Elements, the main books that laid the foundation for modern geometry. In the book, he established the concept of using a small set of axioms to reveal many different geometric theories. No complete original copies of his work survived, so most of his writings exist today from scribes who rewrote his original work. He is known as the father of Geometry. Muhammad ibn Ms al-Khwrizm The father of Algebra lived around 800 A.D. in the Persian Empire. He worked in astronomy, geography, and mathematics, which led him to invent the modern days forms of algebra (itself an Arabic word) and trigonometry. He also popularized the Indian/Arabic form of numbers know in use today. His book Algoritmi gave the West the word algorithm. Other works also showed how to solve both linear and quadratic equations. His books had a great effect on European mathematics when they were translated into Latin. Descartes, who lived in Sixteenth century Europe, is famous for his “I think, therefore, I am” in philosophy. In math, he invented the Cartesian plane and the way of writing exponents, used today in every commonplace mathematical subject. In his life, he worked all across Europe, never wanting to wake up before midday. He finished his life working for the monarchs of Sweden, where he died from Pneumonia. He also created analytical geometry, laying the way for the discovery of calculus. Isaac Newton/Gottfried Wilhelm Leibniz Both Newton and Leibniz are now credited with independently inventing calculus, the math of change. However, this dual creation caused bitter feuds between British mathematicians and the mathematicians on continental Europe. Both sides accused each other of stealing the other’s work. While Newton was probably the first to discover the essential theories of calculus, Leibniz’s notation is used today due to its simplicity. Neither of the two believed in using much mathematical rigor to prove calculus, leaving that task to later generations. Leonhard Euler (1707-1783) was one of the greatest mathematicians of all time, writing around 60-80 volumes of work. His contributions touched all areas of mathematics, from number theory to geometry. He worked on proving some of the assumptions of calculus that Newton and Leibniz failed to do. He developed the Gamma function and numerous constants, among them Euler’s constant or e. Very few fields of mathematics can be learned without touching among one of his contributions. Bernhard Riemann (1826-1866) made contributions to differential geometry, setting the stage for many discoveries in physics in the 20th century. Riemann built on the work of his teacher, Gauss, and developed many ideas for non-Euclidean geometry, which involves geometry on curved surfaces. This helped Einstein formulate his theories of relativity and helped form the study of topology. He is also known for Riemann Sums, a way to solve integrals. Srinivasa Ramanujan (1887-1920) developed many theories in Number Theory during his times in both India and Britain. He filled notebooks with his theories but left little mathematical proof, forcing others to figure out his methods. He easily passed through math in school, but would usually fail out due to ignoring his other subjects. Once he contacted G.H. Hardy, he left for Britain. The two published many papers together as they combed his notebooks for theorems. Ramanujan had a genius for calculation and was usually right about his theorems, even if he didn’t prove them. Edward Witten (1951) is one of the leading Theoretical Physicists of today. He works at the Institute of Advanced Study, where he focuses on Superstring Theory. He was the first physicist to win a Fields medal, an award for young mathematicians. His work in string theory has led to discoveries in topology and geometry. Some consider him to be Einstein’s intellectual successor. These mathematicians are just a few of the many who have influenced the shape of humanity today. Their work has allowed us to better examine the world we live in and to understand humanity’s place in the universe.
Climate Research in the Polar Regions Melting glaciers and ice sheets in the polar regions (Antarctica & Greenland) are increasingly contributing to global sea level rise. Climate models don’t yet adequately capture the true dynamics of these hard-to-measure geophysical wonders. One important technique is airborne radar sounding, which allows the imaging of large swaths of terrain underlying icesheets and glaciers; the shape of this underlying terrain, otherwise invisible to researchers, is a primary factor that governs how these bodies of ice respond to a warming climate and whether (and how fast) they move towards the ocean and disintegrate, contributing to sea level rise. Radar measurements of glaciers that are rough, heavily crevassed, or contain large amounts of debris and water poses a particular challenge in radio glaciology. Water pockets scatter radar signals, which makes the underlying topography difficult to determine. Using multiple unmanned aerial systems (UASs) in a precisely controlled swarm can overcome these challenges, along with the use of tailored antenna beam orientations combined with synthetic and physical aperture processing methods. UASs’ environmental footprints are much smaller than manned aircraft (and are generally more cost effective). In addition, they can stay in the air much longer than human pilots and can follow ground tracks with much higher precision, which is extremely important for glacier radar sounding and for developing synthetic aperture radar (SAR) models. These combined advantages are driving many within the earth science community to consider UASs as a preferred option over manned aircraft. Vulcan Inc's philanthropic team with funding from the Paul G. Allen Family Foundation is supporting the University of Kansas's development of advanced radar systems for UAS platforms. The next generation of ice sheet models require fine-resolution data near the terminus of key glaciers; UAS swarms provide the best approach because of their ability to form large two-dimensional SARs. A UAS platform called G1X was successfully tested during the 2013-14 Antarctic field season where performance of the radar and UAS technology was assessed. The Yak-54 UAS on a test flight over the ice. With their lack of depth perception and active distance measurements, swarming birds rely mainly on their visual perception of other birds to estimate proximity and adjust their flight path. This dynamic provides inspiration for the swarm algorithms under development by KU. The algorithms are tailored for leaderless and self-organizing large fixed-wing UASs with high inertia and high speed. In KU’s control algorithms, classical and proximity-based guidance logics are utilized. Through the Foundation's support, two new radar-equipped G1X UASs are under development. These UASs will go through a series of flight test validations, incorporating lessons learned from the 2013-14 Antarctic mission. G1Xs are mid-wing, semi-autonomous, and high aspect ratio UASs that have been modified by the KU team for Earth and Science missions in polar region. The G1X UAS weighs 86 lbs with a 18.7-foot wingspan. AT LEFT: Two compact UAS sounding radars (~2.5 kg) have been designed to operate at both 14 MHz and 35 MHz with approximately 80 W peak power, using only 20 W of average DC power and a 1.0 and 0.2 μsec pulse duration for the 14 and 35 MHz bands. Separate 14 and 35 MHz antennas were integrated into the aircraft structure. The radar systems were also modified to provide additional in-flight antenna characterization to validate antenna performance in the more representative free-space survey environment. Three new UASs were instrumented to support research on the control of multi-agent fixed-wing UASs. Forty three UAS validation and verification flight tests were successfully conducted through February 2015. The 40% scale Yak-54 UAS (above) weighs 60 pounds with a 9.3-foot wingspan. One of the three, the Bird of Time UAS (below), is a glider that weighs less than 7 pounds with a wingspan of 9 feet. The Bird of Time UAS glider. The KU team came up with a novel approach to safely assess the bio-inspired proximity swarm and associated control algorithms. In this validation, an actual UAS flew autonomously with two virtual UASs. The validation successfully measured the sensitivity of a swarm of small UASs to external disturbances. Actual and virtual UASs held the formation in the presence of windshear, demonstrating the importance of flight control system robustness to external disturbances. The research team was thrilled to see their mathematical modeling and simulations successfully validated. (Above) An actual UAS flew autonomously with two virtual UAS
Using the example of using a magnifying lens to focus light rays onto a piece of paper, ophthalmologist Associate Professor Gordon Sanderson from the University of Otago describes how the lens in the eye functions. The convex lens takes light entering the eye and focuses it to one tiny spot on the retina at the back of the eye. ASSOCIATE PROFESSOR GORDON SANDERSON Well we need to form an image, and the only way you’re going to form an image is with a convex lens. Now you recall when you were a child playing with magnifying glasses, and if you played with it on a sunny day, you would possibly find one location where you could actually form a little bright spot of light, and after a few minutes the paper would start to smoke and you’d burn a hole in the paper. Well what it’s actually done is it’s formed an image of the Sun, and because the rays of the Sun which have been essentially spread over quite a large area have now been brought to a focus at one point, not only has the light been concentrated but the heat from the Sun has also been concentrated as well, and that’s why it gets very hot and that’s why it starts to burn. The convex lens takes a collection of light and focuses it in this one tiny spot, and that of course, if we had multiple sources of light, would form us an image, whereas a diverging lens or a concave lens does the opposite. It takes parallel light and sends it off in a divergent direction so it would actually reduce the illumination on the page. Well the convex lens in general has one major role and that is to converge light. Now if we look at this white piece of paper here, light is falling on that from all over the place, but part of it is falling on it from a light immediately above my head. Now you can’t see where that light is because the light from that light above my head is going off in all different directions. If I put the lens in place and get it to its focal point, now I’m starting to form an image of the actual light itself. Let’s pretend for a minute that this lens here is a combination of our cornea and our crystalline lens. Obviously in this case, they’re rolled into one – in the eye, they’re actually two separate lenses but they’re doing the same job, one is just adding to the effect of the other. So that’s the convex lens, if you like, which we’re going to pretend is our cornea. Now back here somewhere is going to be the retina, and the retina is going to need an image that is a) in focus and b) able to be transmitted to the brain. So that image there, which is the image in this case of the light, is going to be seen by the receptors in that area – when I say seen, that’s going to stimulate receptors in that area as opposed to receptors in this area which won’t be stimulated – and the brain will be able to interpret that there’s light there and there’s not light there. Obviously if we had two sources of light, one image might appear over here, one might appear over there, and the brain would realise that were two separate sources of light and there was a dark space between them and it could then interpret that as an image.
'The Nile' is a trip through Egypt's history via its river 'Nile' author Toby Wilkinson uses the Nile as the basis for an exploration of the various periods of Egypt's history. When Gustave Flaubert visited the south of Egypt in 1849, he claimed the local Egyptians were using the temple of Horus at Edfu as a public latrine. While probably somewhat accurate, the accusation was not quite fair. Sand buried most of the temple until around 1860, and 64 modern houses stood on the temple roof. As in many areas around the world with a long history of human settlement, a modern neighborhood had emerged above a site of great antiquity. From the 19th-century use of the Giza pyramids as stone quarries for construction in Cairo to the 20th-century Theban villagers who built houses above tomb shafts and sold the treasures from their "basements" for extra cash, many examples suggest that some Egyptians have been quite willing to use the artifacts of the past in service of their present needs. But Flaubert's own countrymen often destroyed and stole ancient Egyptian antiquities without even the justification of convenience or cultural patrimony. A French engineer sawed a stunning zodiac from the temple of Dendera in 1821, and the French transported a 250-ton obelisk from Luxor to Paris a decade later. Looting and archaeology were often hard to distinguish in the 19th century. Winding its way through Egypt, the Nile River shaped the ancient civilizations that continue to attract looters, archaeologists, and tourists alike. The river provides the structure for Egyptologist Toby Wilkinson's new book The Nile: A Journey Downriver Through Egypt's Past and Present. The Greek historian Herodotus famously described Egypt as "the gift of the Nile," and Wilkinson shows the many senses in which the observation is true. The river's annual flooding not only initiated the ancient calendar year, it also watered the crops that made the otherwise austere landscape habitable. The Nile's imagery permeated ancient art and literature, its animals inspired religious practices – sacred crocodiles, anyone? – and its sunbaked mud furnished the principal building material for domestic architecture. Customs, food, houses, and art were all aspects of the Nile's gift. Before the 2011 revolution, the seasonal influx of tourists to Egypt seemed to be a force at least as life-giving as the Nile’s annual flood. While roughly 90 percent of the ancient Egyptian economy involved agriculture, the figure has fallen to roughly 30 percent today, with tourism making up some of the difference. The dam at Aswan, built to improve agricultural yields through more precise control of irrigation, helped enable a population boom in the early 20th century. But its high walls also trapped silt that enriches soil quality, and chemical fertilizers are now needed to grow crops in much of the country. The building of the dam submerged several known ancient monuments and countless ones that were still undiscovered. But if the Aswan Dam's construction was an example of the demands of the present overwhelming the claims of the past, many other instances reversed these priorities. Under Mubarak, an entire modern village in western Thebes was demolished and relocated to promote tourism. Wilkinson ostensibly describes a journey down the Nile from Aswan in the south to Cairo in the north. But every site he visits triggers a series of reflections on details spanning the entire history of Egyptian civilization. Covering everything from rock art made 7500 years before the pyramids to the lore of 19th-century tomb-robbers and archaeologists, Wilkinson deftly illustrates the striated density of Egypt’s long past. One of the central themes he pursues is the continuity of certain practices over long time periods. In southern Egypt, he spots mud brick baking in the sun outside ancient Nekheb's city wall, a structure which was made from identical mud bricks 2400 years before. Even the throngs of modern tourists have an ancient precedent. In Thebes, over 2000 ancient Greek and Roman graffiti have been recorded in the Valley of the Kings. The sentiments of ancient visitors are also familiar: one Greek graffito declares that its author has had "a delightful day" among tombs of "astounding horror." The same macabre pleasure still drives countless tourists to the tombs. One thing that has changed is the level of danger faced by archaeologists. In the 19th century, Gertrude Caton-Thompson, the first prominent female Egyptologist, slept during excavations in an abandoned tomb beside a family of cobras. Flinders Petrie, the father of Egyptology, once tracked down a tomb-robber by following his footprints in the sand. But even here there is continuity: terrorist strikes in southern Egypt have made work difficult and visits dangerous for archaeologists and tourists. Despite the many ways Egypt and the field of Egyptology have changed, the persistence of certain practices is inescapable. Around 7000 years ago, farmers in Fayum stored grain in plastered pits dug on their land. Archaeologists were anxious to preserve these early signs of agriculture, and the farmer on whose land they lay agreed at the last minute to work around them. He'd almost plowed over the earliest evidence of agriculture in Egypt. Nick Romeo is a Monitor contributor.
Spinal Tumor is an abnormal mass of tissue within or surrounding the spinal cord and spinal column. These cells grow and multiply uncontrollably, seemingly unchecked by the mechanisms that control normal cells. Spinal tumors can be benign (non-cancerous) or malignant (cancerous). Primary tumors originate in the spine or spinal cord, and metastatic or secondary tumors result from cancer spreading from another site to the spine. Spinal tumors may be referred to by the area of the spine in which they occur. These basic areas are cervical, thoracic, lumbar and sacrum. Additionally, they also are classified by their location in the spine — anterior (front) and posterior (back). Clinically, they are divided into three major groups according to location: intradural-extramedullary, intramedullary and extradural. Nonsurgical treatment options include observation, chemotherapy and radiation therapy. Tumors that are asymptomatic or mildly symptomatic and do not appear to be changing or progressing may be observed and monitored with regular MRIs. Some tumors respond well to chemotherapy and others to radiation therapy. However, there are specific types of metastatic tumors that are inherently radiation resistant (i.e. gastrointestinal tract and kidney), and in those cases, surgery may be the only viable treatment option. Indications for surgery vary depending on the type of tumor. - Primary spinal tumors may be removed through a resection for a possible cure. See laminectomy. - metastatic tumors, treatment is primarily palliative, with the goal of restoring or preserving neurological function, stabilizing the spine and alleviating pain. Generally, surgery is only considered as an option for patients with metastases when they are expected to live 12 weeks or longer, and the tumor is resistant to radiation or chemotherapy. - Indications for surgery include intractable pain, spinal-cord compression and the need for stabilization of impending pathological fractures
The finding could lead to a new, accessible source of stem cells for therapeutic uses, they report. Stem cells have drawn a lot of attention, as they can develop various kinds of cells in the right conditions. Adult stem cells are found in various tissues in the body and can reproduce themselves into various forms of the cells found within the same type of tissue. Researchers say by harnessing a stem cell's natural ability to reproduce and replenish cells, they may be able to develop new therapies to treat disease. In 2004, other scientists identified skin cells, transplanted them into hairless mice, and saw new hairs grow.They mixed those stem cells with Now, the new study, also involving mice, indicates that stem cells from hair follicles can do more than make hair grow. In this study, researchers put the stem cells into lab cultures and watched what happened over the next two months. Within a week, the stem cells started to give rise to cells surrounding a normal hair follicle. They developed into nerve, muscle, and skin cells. Raising the Bar Next, the researchers went a step further. They took stem cells from the lab and transplanted them into hairless mice. Within a week, the cells were on the move, migrating into position under the skin of the mice. After 14 days, the cells had developed into nerve cells, say the scientists. The hair follicle stem cells are "relatively primitive," write the researchers. That widens the cells' range of possibilities, letting them make different kinds of cells, not just the type seen in hair. The researchers included Yasuyuki Amoh of Japan's Kitasato University School of Medicine, San Diego's AntiCancer, Inc., and the University of California, San Diego. The report appears in the early online edition of Proceedings of the National Academy of Sciences.
Melodic percussion instrument A melodic percussion instrument is a percussion instrument used to produce several different notes of different pitches. Melodic percussion instruments are examples of pitched percussion and include mallet percussion and keyboard percussion. Melodic percussion instruments take one of three main forms: - Collections of individual pitched percussion instruments in different pitches, such as hand bells and the angklung. - Instruments that produce different pitches when struck in different places, such as the steel drum. - Instruments that contain a collection of sounding objects tuned to different notes, such as the xylophone. Many melodic percussion instruments have resonators, providing a second way of classifying them: - Some instruments such as the marimba have an individual resonator for each note. - Some instruments such as the hang have a resonator shared by several or all notes. - Some instruments such as the glockenspiel have no resonator. List of percussion instruments that produce musical scales - Ghata tarang - set of ghatams - Glass harp - Handbells set - Kulintang a tiniok - Jal tarang - Loh tarang - Pat waing - Tank drum - Tongue drum - Tabla tarang - Tubular bells - Blades, James. Percussion Instruments and their History (London: Kahn & Averill, 2006) ISBN 978-0-933224-61-2 - http://www.musicaviva.com.au/vivazone/musicians/musician.asp?id=38 retrieved 6 March 2012 the steel drum, a melodic percussion instrument from Trinidad and Tobago |This article relating to percussion instruments is a stub. You can help Wikipedia by expanding it.|
What is CFC and why do we use it? A CFC is a compound containing the elements Carbon , Fluorine and Chlorine. CFCs were developed for use as refrigerants, propellants for aerosols and also a gas to generate foamed plastics such as expanded polystyrene. The compound was so great for all of the above mentioned uses because it was non-flammable (I wouldn't cause fire easily) and also it was non-toxic (It will not harm when inhaled). Although , the CFCs seem perfect for commercial use there is a downside. The CFCs can punch holes through the ozone layer, this happens when carbon to chlorine bonds break high up in the atmosphere to create chlorine radicals(radicals are very reactive indeed). These radicals then go and catalyse the conversion of the ozone(O3) into oxygen (O2) therefore creating holes quickly in the ozone layer. Holes in the ozone layer can allow for harmful UV rays to enter the earth and may potentially damage so people by causing skin cancer. A small amount of CFCs are still used to this day but only with simple alkanes such as Butane (a four carbon chained alkane). An explanation of the harmful parts of CFCs is show in the video below: Naming compounds from numbered CFCs? Many CFC codes have been seen several times before but the actual molecular compound of the numbered and coded molecule is unknown. A way to work out the molecular formula from the numbered CFC you have to break up the three last digits into 3 parts; a , b and c (if there is only two digits a = 0). For example 'CFC-011' a is equalled to 0 in this case and a is also always the number of carbon atoms -1. Moreover , b follows a similar principle where its the number of hydrogen atoms plus one. Lastly, c is simply the number of chlorine atoms.
Translated by Phyllis Jestice Routledge – 2008 – 118 pages Series: Peoples of the Ancient World The Neanderthal is among the most mysterious relatives of Homo sapiens: Was he a dull, club-swinging muscleman, or a being with developed social behaviour and the ability to speak, to plan precisely, and even to develop views on the afterlife? For many, the Neanderthals are an example of primitive humans, but new discoveries suggest that this image needs to be revised. Half a million years ago in Ice Age Europe, there emerged people who managed to cope well with the difficult climate – Neanderthal Man. They formed an organized society, hunted Mammoths, and could make fire. They were able to pass on knowledge; they cared for the old and the handicapped, burying their dead, and placing gifts on their graves. Yet, they became extinct, despite their cultural abilities. This richly illustrated book, written for general audiences, provides a competent look at the history, living conditions, and culture of the Neanderthal. 1.The History of the Neanderthal 2. Out of Africa 3. The Settlement of the "New World" 4. From Heidelberg Man to the Classic Neanderthal 5. Elderberries, Mammoths, and Spears 6. Encounters with the Modern Important Fossil Sites of the Early Europeans. Suggestions for Further Reading. Index
- A very short statement that describes what you're studying. Two or three words are usually all you need. For example, if you're supposed to write a report about the world's tropical rain forests, you could use Rain Forests as your main topic. - These are concepts, thoughts, and ideas that pertain to the main topic. Whenever you study a topic, you'll soon start to uncover important details about it. Every time you find out something meaningful about your topic, put it in your concept web as a related idea. Two or three words are usually enough to describe a related A Simple Concept Web example: Let's say you really did have to write a report on tropical rain forests, and you decide to make your own concept web. Great! Here's how you do it: - Write Rain Forests in the center circle as the main topic. - If you already know some related ideas (like tropics or ecology), write them in one of the circles attached to the center circle. - Do a search on the words in your main topic circle: "rain - Find some articles about rain forests that you think are good ones. - Read these articles thoroughly and discover some related ideas about your topic. Think of a way to describe each related idea in as few words as possible. Then write these words in one of the circles attached to the center circle. - Do a new search, this time using the words in one of your related idea circles as the search words. - Keep filling in the small circles with related ideas until you're sure you've covered everything that's important about rain forests. After you've done some research and found some related ideas, your concept web might look like this: A Great Big Hint: If you're having trouble finding related ideas for your concept web, this product can actually find some for you! It works like this: every time you find a good article about your topic using this product, look for the "View other articles linked to these subjects" area. You should see links to other articles that are related to your subject. Now, look at the words in bold print that appear under the statement View other documents linked to these subjects. Chances are, the words you see in bold print are ideas that are closely related to your main topic. So, take advantage of what the Student Resource Center can do for you. Use the Link feature to help you identify related ideas for your concept web. Complex Concept Webs. Consider our Rain Forest concept web once again. Every one of the related ideas in the small circles is an interesting research topic in itself. So, let's do some research using the related idea words as our search words. As we do this, we'll discover more concepts that are worth exploring. For example, if we do Student Resource Center searches on biological diversity and endangered species, we can find a few more meaningful ideas related to this topic. Here's how our concept web looks Got the idea? Good! Now you're ready to make your own concept webs!
The auroral light shows that appear in the sky near Earth’s poles — aurora borealis in the North, aurora australis in the South — have captivated humans for centuries and contributed to mythology around the world. We now know that auroras are caused by electrons and other charged particles from the sun being funneled by Earth’s magnetic field towards the poles, where they hit air molecules in Earth’s upper atmosphere at 45 million miles per hour. The energy from the collision causes the molecules to give off bursts of light. Put together the tiny bursts of light from a bunch of molecules — green and red from oxygen, blue and purple from nitrogen — and you get the shimmering colors of an aurora. But researchers weren’t sure exactly how auroral electrons could be accelerated to the energy they were observed hitting the atmosphere with. Now, a group of physicists have answered that question with an experiment showing that aurora-causing electrons can accelerate towards Earth by “surfing” on plasma waves created by solar weather disturbing Earth’s magnetic field. Space Weather, Magnetic Slingshots and Surfing Particles The sun is constantly sending out a “solar wind” of hot, charged plasma particles, mostly electrons and protons. The wind speed and particle density vary depending on surface conditions and the sun’s magnetic cycle. Sometimes, solar storms whip out big bursts of particles called coronal mass ejections. Our planet’s trusty magnetic field protects us from the harshest solar radiation by redirecting the bulk of it around and away from our planet. But space weather can still impact satellites, astronauts, and even Earth’s electrical grid. Auroras also appear much brighter during times of intense solar weather. Coronal mass ejections or particularly strong gusts of solar wind can stretch the Earth’s magnetic field lines out behind the Earth until they snap back like a slingshot, creating ripples in the plasma called Alfvén waves (there are other ways to make Alfvén waves too but this is the type most relevant to auroras). As the waves travel towards Earth, the magnetic field gets stronger, and they speed up. At some point, around 16,000 miles from Earth, the waves reach a magical speed where they’re going just a little bit faster than the electrons around them. Some of the electrons can then hitch a ride on the accelerating Alfvén wave. Greg Howes, a physicist at the University of Iowa and one of the lead researchers on the study, compares it to a surfer catching a wave on the ocean. “You've got to almost match the speed of the wave going just a little bit slower. That's where you catch the wave and start surfing.” Only the fraction of electrons that happen to be headed in the right direction at the right speed will catch the wave (for the rest, the wave simply passes them by). At least, that was the idea. Though satellite observations of Alfvén waves and electrons in Earth’s magnetosphere were consistent with the concept of surfing electrons, nobody had actually proven that it was possible until recently. “We know that that the electrons coming down and the waves often exist together,” says Jim Schroeder, a physicist at Wheaton College who worked with Howes on the experiment since he was a grad student at Iowa. “But there had never been a measurement showing that the waves can accelerate the electrons.” Can Electrons Catch a Wave? While satellite-based observations have plenty of merits, the researchers knew that they needed more controlled conditions to be able to see how the waves and electrons interact with each other. So, they turned to Earth-based experiments. “We were able to really dial in and study a level of detail that you just you can't with a spacecraft that's moving,” says Schroeder. If the observing satellite were in a fixed position, like a buoy tethered to the ocean floor, it would be simple to watch the Alfvén waves and see if they were accelerating any electrons. But satellites don’t stay still; they’re in orbit, which adds up to simply too many moving pieces. In the late 1990s, Craig Kletzing, one of Howes’ physics colleagues at the University of Iowa, struck up a collaboration with UCLA’s Basic Plasma Science Facility. His plan was to recreate the plasma conditions present in Earth’s magnetosphere, send some Alfvén waves through it, and see if some portion of the electrons picked up speed. “He initially thought it would take about three years,” says Howes. “It took more like 20.” Every stage of the project presented a fresh technical challenge: how to send Alfvén waves through the 20-meter-long plasma chamber, how to scale everything so that it was proportional to what would happen in space, how to measure whether the electrons were accelerating, how to model the data. But ultimately, they succeeded in designing the experiment and showing that electrons can ride Alfvén waves. Schroeder recalls being in the lab at UCLA late one night in 2018, plotting some of his data and seeing that it agreed with the surfing hypothesis. “I’d done enough theory that I sort of knew what it would look like if we had captured this process and seen the signal in our data, and it was there.” He immediately sent a photo of the plot to his brother, also a physicist — not a plasma physicist, but knowledgeable enough to look at the plot and understand that it was exciting. “They were very nicely able to show with this experiment that this particular [electron-accelerating] mechanism has the characteristics needed to be able to explain what’s going on in the upper atmosphere and in space,” says David Schaffner, a physicist at Bryn Mawr College who was not involved with the research. In the Eye of the Storm Understanding what’s going on in space and how space weather affects Earth’s magnetosphere has more serious implications too. Radiation from solar flares can mess with power grids and telecommunications systems — a solar storm knocked out power to the entire province of Quebec in 1989 — and also poses safety hazards for astronauts and airplanes. The better we understand how solar weather affects near-Earth space, the better we can predict and prepare for it. As Schaffner put it, “If you lived in the middle of the ocean, you’d want to know what’s going on with the currents.” So the next time you see an aurora rippling across the night sky, in real life or on a screen, consider the surfing electrons and the space weather that makes them possible – and say thank you to the magnetosphere for making sure we don’t get scorched by solar winds.
The primary purpose of stairs is to provide a simple and easy means of moving between levels. Formula to calculate stairs. First, lets take a look at the regulations that are normally used in the construction of stairs. Suppose you are supposed to put non spiral stairs on a floor of 750mm due to its change in level (rise). Since 2R + G = (550-700), calculate the number of steps and the slope relationship. Since we know that the riser should be from 115 to 190, lets take 150mm to be our riser, therefore the number of steps needed is; = 750 ÷ 150 Therefore, 5 steps whose rise is 150mm should be constructed. G should be between 240-355, so lets take 250 to be our going. Slope relationship = 2R + G = (2 x 150) + 250 The slope relationship is 550. It is within the range 550-700 so it is acceptable.
First Time User? Enroll now. Get Care Now COVID-19: Vaccine information, visitor restrictions, testing, treatment, and additional resources Home > Health Library > Avian Influenza (Bird Flu) Bird flu is an infection caused by a certain kind of avian influenza virus. Although there are many kinds of bird flu, the most common kinds that concern health workers are H5N1 and H7N9 bird flu viruses. These viruses are found in wild birds. Most of the time, wild birds don't get sick from the virus. But wild birds can easily pass the virus to birds that are being raised for food, such as chickens, ducks, and turkeys. The virus can cause them to get very sick. Usually bird flu virus is not passed from birds to people. But since 1997, some people have become sick with this serious, deadly kind of bird flu. Most of these infections have been in Asian countries among people who have had close contact with birds raised on farms. Bird flu is caused by a virus. After a wild bird infects a farm-raised bird, the virus can easily and quickly spread among hundreds or thousands of birds. Sick birds must then be killed to stop the virus from spreading. People who come into contact with sick chickens, ducks, or turkeys are more likely to get the virus. Bird flu virus can be passed through bird droppings and saliva on surfaces such as cages, tractors, and other farm equipment. Most people don't need to worry about getting sick with bird flu virus. You cannot get bird flu from eating fully cooked chicken, turkey, or duck, because heat kills the virus. In a few cases, bird flu was passed from one person to another person, not from a bird to a person. But this was very rare. The bird flu virus can make people sicker than other kinds of flu viruses. Even though only a few hundred people are known to have been sick with bird flu, more than half of them have died. Experts worry because the bird flu virus is so different from other flu viruses that our bodies do not have immunity against it. Not having immunity means that our bodies have a hard time fighting the virus. It also means that anyone, including those who are otherwise very healthy, can get seriously ill if they get bird flu. At first, the symptoms of bird flu can be the same as common flu symptoms, such as: Sometimes bird flu also can cause other symptoms, such as: Bird flu can quickly progress to pneumonia and acute respiratory distress syndrome, a serious lung problem that can be deadly. If your doctor thinks that you may have bird flu, your doctor will do a physical exam and ask you questions about your symptoms and past health. Your doctor will also ask where you live, where you have traveled recently, and if you have been near any birds. Then your doctor may order blood tests, nasal swabs, or other tests, such as X-rays, to help find out what is making you sick. How bird flu is treated depends on what the virus is doing to your body. In some cases, antiviral medicines may help you feel better. But experts are concerned that certain antiviral medicines may not work against bird flu. If you have bird flu, you will stay in a private hospital room (isolation room) to reduce the chances of spreading the virus to others. When your doctors and nurses are caring for you, they will wear gloves and gowns. Some people who have bird flu may need a machine called a ventilator to help them breathe better. Other people may need a machine to help the kidneys work better (dialysis). These organizations are studying and keeping track of bird flu, including what is being done to prevent its spread. Their websites have the most up-to-date information about bird flu: Current as of: February 9, 2022 Author: Healthwise StaffMedical Review: Adam Husney MD - Family MedicineE. Gregory Thompson MD - Internal MedicineLeslie Tengelsen PhD, DVM - Zoonotic Disease Current as of: February 9, 2022 Author: Healthwise Staff Medical Review:Adam Husney MD - Family Medicine & E. Gregory Thompson MD - Internal Medicine & Leslie Tengelsen PhD, DVM - Zoonotic Disease To learn more about Healthwise, visit Healthwise.org. © 1995-2022 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.
page from sketchbook Rouen is a city on the River Seine in the north of France. It is the capital of the region of Upper Normandy and the historic capital city of Normandy. One of the largest and most prosperous cities of medieval Europe, it was the seat of the Exchequer of Normandy in the Middle Ages. It was one of the capitals of the Anglo-Norman dynasties, which ruled both England and large parts of modern France from the 11th to the 15th centuries. It was here that Joan of Arc was executed in 1431. People from Rouen are called Rouennais. Unknown to Julius Caesar, Rouen was founded by the Gaulish tribe of the Veliocasses, who controlled a large area in the lower Seine valley, which retains a trace of their name as the Vexin. They called it Ratumacos; the Romans called it Rotomagus. Roman Rotomagus was the second city of Gallia Lugdunensis after Lugdunum (Lyon) itself. Under the reorganization of the empire by Diocletian, Rouen became the chief city of the divided province of Gallia Lugdunensis II and reached the apogee of its Roman development, with an amphitheatre and thermae of which the foundations remain. In the 5th century, it became the seat of a bishopric and later a capital of Merovingian Neustria. From their first incursion into the lower valley of the Seine in 841, the Vikings overran Rouen until some of them finally settled and founded a colony led by Rollo (Hrolfr), who was nominated count of Rouen by the king of the Franks in 911. In the 10th century Rouen became the capital of the Duchy of Normandy and residence of the dukes, until William the Conqueror established his castle at Caen. In the early 12th century the city's population reached the size of 30,000. In 1150, Rouen received its founding charter, which permitted self-government. During the 12th century, Rouen was probably the site of a Jewish yeshiva. At that time, about 6,000 Jews lived in the town, comprising about 20% of the total population. In addition, there were a large number of Jews scattered about another 100 communities in Normandy. The well-preserved remains of a medieval Jewish building, that could be a yeshiva, were discovered in the 1970s under the Rouen Law Courts. In 1200, a fire destroyed part of the old Romanesque cathedral, leaving St Romain's tower, the side porches of the front, and part of the nave. New work on the present Gothic cathedral of Rouen was begun, in the nave, transept, choir, and the lowest section of the lantern tower. On 24 June 1204, Philip II Augustus of France entered Rouen and annexed Normandy to the French Kingdom. The fall of Rouen meant the end of Normandy's sovereign status. He demolished the Norman castle and replaced it with his own, the Château Bouvreuil, built on the site of the Gallo-Roman amphitheatre. A textile industry developed based on wool imported from England, for which the northern County of Flanders and Duchy of Brabant were constantly fierce but worthy competitors, and finding its market in the Champagne fairs. Rouen also depended for its prosperity on the river traffic of the Seine, on which it enjoyed a monopoly that reached as far upstream as Paris. Wine and wheat were exported to England, with tin and wool received in return. In the 14th century urban strife threatened the city: in 1291, the mayor was assassinated and noble residences in the city were pillaged. Philip IV reimposed order and suppressed the city's charter and the lucrative monopoly on river traffic, but he was quite willing to allow the Rouennais to repurchase their former liberties in 1294. In 1306, he decided to expel the Jewish community of Rouen, which then numbered some five or six thousand in the city of 40,000 people. In 1389, another urban revolt of the underclass broke out, the Harelle. It was part of a widespread rebellion in France that year and was suppressed with the withdrawal of Rouen's charter and river-traffic privileges once more. During the Hundred Years' War, on 19 January 1419, Rouen and its population of 70,000 surrendered to Henry V of England, who annexed Normandy once again to the Plantagenet domains. But Rouen did not go quietly: Alain Blanchard hung English prisoners from the walls, for which he was summarily executed; the Canon and Vicar General of Rouen, Robert de Livet, became a hero for excommunicating the English king, resulting shortly after in de Livet's himself imprisonment for five years in England. Rouen became the capital city of English power in occupied France and when the Duke of Bedford, John of Lancaster bought Joan of Arc from his ally, the Duke of Burgundy who had been keeping her in jail since May 1430, she was sent to be tried in this city on Christmas 1430. After a long trial by a church court, sentenced to be burned at the stake. The sentence was carried out on 30 May 1431 in this city, where most inhabitants supported the Duke of Burgundy, Joan of Arc's royal enemy. The king of France Charles VII recaptured the town in 1449, 18 years after the death of Joan of Arc and after 30 years of English occupation. In that same year the young Henry VI was crowned king of England and France in Paris before coming to Rouen where he was acclaimed by the crowds. The naval dockyards, where activity had been slowed down by the 100 years war, developed again as did the church of Saint-Maclou which had been started under the English occupation, and was finally finished during the Renaissance period. The nave of the church of Saint Ouen was completed at last, but without the façade flanked by twin towers. The salle des pas-perdus (a sort of waiting room or ante-room) of the present law courts was built during this time. The whole building was built in a flamboyant style into which the first decorative elements typical of the Renaissance style right at the beginning of the 16th century had been incorporated. At that time Rouen was the most populous city in the realm after Paris, Marseille and Lyon. Rouen was also one of the Norman cradles of the artistic Renaissance, in particular the one under the patronage of the archbishops and financiers of the town. The economic upturn of the town at the end of the 15th century was mainly due to the cloth industry, but also to the development of the silk industry and metallurgy. The fishermen of Rouen went as far afield as the Baltic to fish for herrings. Salt was imported from Portugal and Guérande. Cloth was sold in Spain which also provided wool, and the Medici family made Rouen into the main port for the resale of Roman alum. At the beginning of the 16th century Rouen became the main French port through which trade was conducted with Brasil, principally for the import of cloth dyes. By 1500 ten printing presses had been installed in the town following the installation of the first one sixteen years earlier. In the years following 1530, part of the population of Rouen embraced Calvinism. The members of the Reformed Church who represented a quarter to a third of the total population, a significant part but still a minority. In 1550, King Henri II staged a triumphant entry into Rouen, modeled on the ancient Roman triumph and specifically compared to Pompey's third triumph of 61 BC at Rome: "No less pleasing and delectable than the third triumph of Pompey... magnificent in riches and abounding in the spoils of foreign nations". It was not enough, however, to long sustain royal authority in the city. From 1560 onwards tensions rose between the Protestant and Catholic communities, when the Massacre of Vassy set off the first of the French Wars of Religion. On 15 April 1562 the Protestants entered the town hall and ejected the King's personal representative. In May there was an outbreak of Iconoclasm (statue smashing). On 10 May the Catholic members of the town council fled Rouen. The Catholics captured, however, the Fort of Saint Catherine which overlooked the town. Both sides resorted to terror tactics. At this juncture the Protestant town authorities requested help from Queen Elizabeth I of England. In accordance with the Hampton Court Treaty which they had signed with Condé on 20 September 1562, the English sent troops to support the Protestants, and these occupied Le Havre. On 26 October 1562 French Royalist troops retook Rouen and pillaged it for three days. The news of the Massacre of St. Bartholomew's Day reached Rouen at the end of August 1572. Hennequier tried to avoid a massacre of the Protestants by shutting them up in various prisons. But between 17 and 20 September the crowds forced the gates of the prisons and murdered the Protestants that they found inside. The town was attacked on several occasions by Henry IV, but it resisted, notably during the siege of December 1591 to May 1592, with the help of a Spanish army led by the Duke of Parma (see Siege of Rouen (1591)). The permanent exchequer of Normandy, which had been installed in Rouen in 1499 by George of Amboise, was transformed into a regional administrative assembly by Francis I in 1515 and up to the time of the Revolution was the administrative centre of the region. It had judicial, legislative and executive powers in Norman affairs and was only subordinate to the Privy Council. It also had power to govern French Canada. The 16th and the 18th centuries brought prosperity to the town through the textile trade and the increased use of the port facilities. In 1703 the Norman Chamber of Commerce was formed. Although it did not have a university, Rouen became an important intellectual centre by reason of its reputed schools of higher learning. In 1734, a school of surgery (second only to that of Paris founded in 1724) was founded. In 1758 a new hospital was opened to the West of the town which replaced the old medieval one which had grown too small, and which had been situated on the south side of the cathedral. During the First World War the British used Rouen as a supply base and there were many military hospitals. The city was heavily damaged during World War II - approximately 45% was destroyed. In June 1940 the area between the Notre-Dame Cathedral and the Seine river burned for 48 hours because the Germans did not allow firemen access to the fire. Other areas were destroyed between March and August 1944 just before and during the Battle of Normandy, which ended on the left bank of the Seine with the destruction of several regiments belonging to the German 7th Army. Rouen's cathedral and several significant monuments were damaged by Allied bombing. During the German occupation, Nazi Germany's Kriegsmarine had its headquarters located in a château on what is now the Rouen Business School (École Supérieure de Commerce de Rouen). The city was liberated by the Canadians on 30 August 1944 after the breakout from Normandy. A church was already present at the location in the late 4th century, and eventually a cathedral was established in Rouen as in Poitiers. It was enlarged by St. Ouen in 650, and visited by Charlemagne in 769.All the buildings perished during a Viking raid in the 9th century. The Viking leader, Rollo, founder of the Duchy of Normandy, was baptised here in 915 and buried in 931. His grandson, Richard I, further enlarged it in 950. St. Romain's tower was built in 1035. The buildings of Archbishop Robert II were consecrated in 1065. The cathedral was struck by lightning in 1110. Construction on the current building began in the 12th century in Early Gothic style for Saint Romain's tower, front side porches and part of the nave. The cathedral was burnt in 1200. Others were built in High Gothic style for the mainworks: nave, transept, choir and first floor of the lantern tower in the 13th century; side chapels, lady chapel and side doorways in the 14th century. Some windows are still decorated with stained glass of the 13th century, famous because of a special cobalt blue colour, known as "the blue from Chartres". The north transept end commenced in 1280. The cathedral was again struck by lightning in 1284. In 1302, the old Lady chapel was taken down and the new Lady chapel was built in 1360. The spire was blown down in 1353, choir windows were enlarged in 1430, the upper storey of the north-west tower was added in 1477, gable of the north transept built in 1478. Some more parts were built in Late (Flamboyant) Gothic style, these include the last storey of Saint Romain's Tower (15th century), the Butter Tower, main porch of the front and the two storeys of the lantern tower (16th century).Construction of the south-west tower began in 1485 and was finished in 1507. The Butter Tower was erected in the early 16th century. Butter was banned during Lent and those who did not wish to forgo this indulgence would donate monies of six deniers Tournois from each diocesan for this permission. The realization of the Butter Tower caused disturbances in the façade, which caused the reconstruction of the central portal and the west front, which begun in 1509 and finished in 1530. The original Gothic spire suffered a fire in 1514, nevertheless the project of a stone spire was denied and a wooden construction covered with gold-plated lead was begun in 1515, a parapet was added in 1580.In the late 16th century the cathedral was badly damaged during the French Wars of Religion: the Calvinists damaged much of the furniture, tombs, stained-glass windows and statuary. The cathedral was again struck by lightning in 1625 and 1642, then damaged by a hurricane in 1683, the wood-work of the choir burnt in 1727 and the bell broke in 1786. In the 18th century, the state (government) nationalised the building and sold some of its furniture and statues to make money and the chapel fences were melted down to make guns to support the wars of the French Republic. The Renaissance spire was destroyed by lightning in 1822. A new one was rebuilt in Neo-Gothic style, but of other material : cast iron. The cathedral was named the tallest building (the lantern tower with the cast iron spire of the 19th century) in the world (151 m) from 1876 to 1880. In the 20th century, during World War II, the cathedral was bombed in April 1944 by the British Royal Air Force. Seven bombs fell on the building, narrowly missing a key pillar of the lantern tower, but damaging much of the south aisle and destroying two rose windows. One of the bombs did not explode. A second bombing by the U.S. Army Air Force (before the Normandy Landings in June 1944) burned the oldest tower, called the North Tower or Saint-Romain Tower. During the fire the bells melted, leaving molten remains on the floor. In 1999, during a violent wind storm, a copper-clad wooden turret, which weighed 26 tons, broke and fell partly into the church and damaged the choir. The cathedral has a strong musical tradition since the Middle Ages. Its choir was famous up to the French Revolution for singing from memory. The first major organist to work here was Jean Titelouze, the so-called father of the French organ school. He occupied the post of the titular organist in 1588–1633. Around 1600 in collaboration with the famous Franco-Flemish organ builder Crespin Carlier, Titelouze transformed the organ of the cathedral to one of the best instruments in France. Some 80 years later the legendary organ builder Robert Clicquot restored and enhanced the instrument; organists who played the new organ included distinguished composers such as Jacques Boyvin (in 1674–1706), and François d'Agincourt (1706–1758). New organs were built by Merklin & Schütze (1858–60) and, after World War II, by Jacquot-Lavergne. The most famous paintings of the cathedral were done by the Impressionist artist Claude Monet, who produced a series of paintings of the building showing the same scene at different times of the day and in different weather conditions. Two paintings are in the National Gallery of Art in Washington, D.C.; one is in the Getty Center in Los Angeles, CA; one is in the National Museum of Serbia in Belgrade; one is in a museum of Cologne; one is in the Rouen fine art museum; and five are in the musée d'Orsay in Paris. The estimated value of one painting is over $40 million. Other painters inspired by the building included John Ruskin, who selected it as an example of good architecture in The Seven Lamps of Architecture, and Roy Lichtenstein, who produced a series of pictures representing the cathedral's front. Mae Babitz, known for illustrations of the Watts Towers and Victorian era buildings in Los Angeles, illustrated the Cathedral in the 1960s. Those works are held in the UCLA library Special Collections. Boys was born at Pentonville, London, on 2 January 1803. He was articled to the engraver George Cooke. When his apprenticeship came to an end he went to Paris where he met and came under the influence of Richard Parkes Bonington, who persuaded him to abandon engraving for painting. Some sources describe him as a pupil of Bonington, although William Callow, who later shared a studio with him in Paris, disputed this. He exhibited at the Royal Academy for the first time in 1824, and in Paris in 1827. In 1830 he went to Brussels, but returned to England on the outbreak of the revolution there. Paying another visit to Paris, he remained there until 1837, and then returned to England in order to lithograph the works of David Roberts and Clarkson Stanfield. His most important work, Picturesque Architecture in Paris, Ghent, Antwerp, Rouen, etc., a collection of colour lithographs, appeared in 1839, attracting a great deal of admiration.Drawn on the stone by Boys and printed by Charles Joseph Hullmandel, it was described in a review in the Polytechnic Journal as "the first successful effort in chroma-lithography hitherto brought to perfection". King Louis-Philippe sent the artist a ring in recognition of its merits. He also published Original Views of London as it is, drawn and lithographed by himself, (London, 1843). He drew the illustrations to Blackie's History of England, and etched some plates for John Ruskin's Stones of Venice. Boys was a member of the Institute of Painters in Water Colours, and of several foreign artistic societies. He died in 1874.
During the warmer weather, your child may start noticing new things in the world around them – including insects like bees and butterflies! Here is the Beehive is a great way to introduce our pollinator friends to small children! Help toddlers and preschoolers understand the important role bees play in the world, helping pollinate beautiful flowers, producing delicious food, and more! This song can be used in many different ways as well, to keep the lesson engaging and fun! Here are some suggestions: - Use a parachute as the “hive” and choose 5 children as “bees” to act out the song - Use your hands as the imaginary beehive and count up to 5 imaginary bees - Sing along with the tempo, learning to go from slow to a faster beat - Use finger puppets or stuffed animals as the bees We’d love to know how you incorporate this song into your lesson plans! Looking for more ways to teach kids about bees? Check out these fun ideas: Talk to a Local Beekeeper Whether virtually or in-person, having a chat with a bee professional can help children conquer any fears they may have about the small insects, answer burning questions, and instill a healthy respect for nature! Kids love to explore their creative side. Create a beehive out of a small container, like a wastebasket or plastic container. Then let the kids draw their very own bees to fill up the hive! Take a Nature Walk If you have local forestry or gardens, plan some outdoor time to visit the bees in their natural habitat. Make sure to stress safety first and be alert for any possible allergies. Seeing the bees hard at work can be inspiring and help you explain the pollination process. Snack Time with Honey What better way to help kids appreciate our bee friends than by sharing honey with them? Here are some additional resources to learn more about bees as well! - National Geographic Kids: 10 Facts about Honey Bees - Pest World for Kids: Bees - Pollination for Kids – YouTube Video
Digraph Beginning Sound Interactive Learning Games Phoneme Worksheets Digraph Beginning Sound Interactive Learning Games Phoneme Worksheets. Kids can follow the path, color each word, and practice phonics. worksheet. next, check out our free book called math in the bath. voiced and voiceless. makes sounds as in bath and as in then. the. Worksheets kindergarten phonics phonemes. phonemes and writing sounds. these free worksheets focus on the relationship between sounds and letters and give students practice in writing words by sounding them out. these worksheets compliment our phonics and phonemic awareness lessons. Sounds and phonics worksheets for preschool and kindergarten, including beginning sounds, consonants, vowels and rhyming. these worksheets help kids learn to use letters to make sounds and words. free phonics worksheets from k learning no required. free phonics worksheets included in your teacher account is access to free phonics worksheets to use as a whole class, a reading rotation activity or homework. for every level, there are phonics worksheets covering each skill that phonics hero teaches. Printable phonics worksheets for kids. check out our different sets of worksheets that help kids practice and learn phonics skills like beginning sounds, rhyming and more. Digraph recognition worksheet ow phoneme worksheets. Printable phonics worksheets early learners phoneme. Worksheet packet digraphs worksheets distance learning phoneme. Digraph phonics worksheets activities elementary students phoneme. Read write worksheet teacher phoneme worksheets. Free worksheets kindergarten phoneme. Sh ch word sort activities free den phoneme worksheets.
Download CBSE Class 11 Computer Science books, NCERT Solutions, Latest sample papers and past year question papers with solutions. Also access latest syllabus and guidelines issued by CBSE and NCERT. Get important questions and answers for all chapters.All study material has been prepared based on latest guidelines, term examination pattern and blueprint issued by cbse and ncert Click below for Class 11 Computer Science worksheets, assignments, syllabus, ncert cbse books, ncert solutions, easy to learn concepts and study notes of all chapters Please refer to the most updated syllabus for Class 11 Computer Science No major prerequisites are required for this course other than basic Mathematical skills. However, it will be helpful if the student has a basic knowledge of Computer Applications. 2. Learning Outcomes a) Develop basic computational thinking. Learn how to reason with variables, state transitions, conditionals, and iteration. b) Understand the notion of data types, and higher order data structures such as lists, tuples, and dictionaries. c) Appreciate the notion of an algorithm, and understand its structure, including how algorithms handle corner cases. d) Develop a basic understanding of computer systems - architecture, OS, mobile and cloud computing. e) Learn basic SQL programming. f) Learn all about cyber safety. 3. Distribution of Marks Programming and Computational Thinking - 1 Computer Systems and Organisation Data Management - 1 Society, Law and Ethics - 1 4.1 Unit 1: Programming and Computational Thinking (PCT-1) (80 Theory + 70 Practical) a) Familiarization with the basics of Python programming: a simple “hello world" program, process of writing a program, running it, and print statements; simple data-types: integer, float, string Introduce the notion of a variable, and methods to manipulate it (concept of L-value and R- value even if not taught explicitly) b) Knowledge of data types and operators: accepting input from the console, assignment statement, expressions, operators and their precedence. c) Conditional statements: if, if-else, if-elif-else; simple programs: e.g.: absolute value, sort 3 numbers, and divisibility. d) Notion of iterative computation and control flow: for, while, flowcharts, decision trees and pseudo code; write a lot of programs: interest calculation, primarily testing, and factorials. e) Idea of debugging: errors and exceptions; debugging: pdb, break points. f) Lists, tuples and dictionary: finding the maximum, minimum, mean; linear search on list/tuple of numbers, and counting the frequency of elements in a list using a dictionary. Introduce the notion of accessing elements in a collection using numbers and names. g) Sorting algorithm: bubble and insertion sort; count the number of operations while sorting. h) Strings: compare, concat, substring; notion of states and transitions using state transition diagram 4.2. Unit 2: Computer Systems and Organisation (CSO) (20 Theory + 6 Practical) a) Basic computer organisation: description of a computer system and mobile system, CPU, memory, hard disk, I/O, battery, power. b) Types of software: application, OS, utility, libraries. c) Language of Bits: bit, byte, MB, GB, TB, and PB. d) Boolean logic: OR, AND, NAND, NOR, XOR, NOT, truth tables, De Morgan’s laws e) Information representation: numbers in base 2, 8, 16, unsigned integers, binary addition f) Strings: ASCII, UTF8, UTF32, ISCII (Indian script code) g) Execution of a program: basic flow of compilation – program à binary à execution h) Interpreters (process one line at a time), difference between a compiler and an interpreter i) Running a program: Notion of an operating system, how an operating system runs a program, idea of loading, operating system as a resource manager. j) Concept of cloud computers, cloud storage (public/private), and brief introduction to parallel computing. 4.3. Unit 3: Data Management (DM-1) (30 Theory+ 24 Practical) a) Relational databases: idea of a database and the need for it, relations, keys, primary key, foreign key; use SQL commands to create a table, keys, foreign keys; insert/delete an entry, delete a table. b) SQL commands: select, project, and join; indexes, and a lot of in-class practice. c) Basics of NoSQL databases - Mongo DB. 4.4. Unit 4: Society, Law and Ethics (SLE-1) - Cyber safety (10 Theory) a) Cyber safety: safely browsing the web, identity protection, confidentiality, social networks, cyber trolls and bullying b) Appropriate usage of social networks: spread of rumours, and common social networking sites (Twitter, LinkedIn, and Facebook) and specific usage rules. c) Safely accessing web sites: adware, malware, viruses, Trojans d) Safely communicating data: secure connections, eavesdropping, phishing and identity verification. Lab Test (12 marks) Python program (60% logic + 20% documentation + 20% code quality) SQL program (at least 4 queries) Report File + viva (10 marks) Report file: Minimum 20 Python programs and 8 SQL commands Viva voce (based on the report file) Project (that uses most of the concepts that have been learnt) (See CS-XII for the rules regarding the projects). 5.1. Programming in Python: At least the following Python concepts should be covered in the lab sessions: expressions, conditionals, loops, list, dictionary, and strings. The following are some representative lab assignments. a) Find the largest and smallest numbers in a list. b) Find the third largest number in a list. c) Test for primarily. d) Find whether a string is a palindrome or not. e) Given two integers x and n, compute xn. f) Compute the greatest common divisor and the least common multiple of two integers. g) Test if a number is equal to the sum of the cubes of its digits. Find the smallest and largest such numbers. 5.2. Data Management: SQL Commands At least the following SQL commands should be covered during the labs: create, insert, delete, select, and join. The following are some representative assignments. a) Create a student table with the student id, name, and marks as attributes where the student id is the primary key. b) Insert the details of a new student in the above table. c) Delete the details of a particular student in the above table. d) Use the select command to get the details of the students with marks more than 80. e) Create a new table (name, date of birth) by joining two tables (student id, name) and (student id, date of birth). f) Create a new table (order ID, customer Name, and order Date) by joining two tables (order ID, customer ID, and order Date) and (customer ID, customer Name, contact Name, country). Latest NCERT & CBSE News Read the latest news and announcements from NCERT and CBSE below. Important updates relating to your studies which will help you to keep yourself updated with latest happenings in school level education. Keep yourself updated with all latest news and also read articles from teachers which will help you to improve your studies, increase motivation level and promote faster learning For 2021-22 CBSE has launched MCQ question-based examination for Term 1 & Term 2 board examinations. The entire syllabus has been divided into two parts each including 50% of the entire syllabus. To score well, students must practice as per the new CBSE term-wise... 12th Board exams are an important part of students' lives. The marks obtained in the board exam decide the college in which one can study. In class 12 the syllabus of each and every subject increases vastly and it is difficult to cover up every point. In English also... Unseen passages may contain one or many paragraphs. This is one of the important yet easy parts for a student to get marks. Students should thoroughly study and understand the passage to answer the related questions. The unseen passages are there just to test the... Last year CBSE had to reduce the syllabus because of the pandemic situation but it was not very effective because there were no examinations. This year to avoid any confusion and conflict, CBSE has decided to reduce the syllabus into term 1 and term 2. 50 percent of...
What Is Flyover? The difference between the Bridge and Flyover is depending on the purpose of its use and the location where it is being built. Bridges are built to connect two separate points it is a region that occurs naturally like a valley, river, sea or anywhere other bodies of water, etc. Whereas Flyover is designed to connect two points in congested areas or roads and intersections of roads. Bridge and flyovers are facilities that provide passage over an obstacle without blocking the path below. The passage required may be a road, railway, or a valley. Types of Flyover: There are two types of flyovers used for traffic management when crossing the road. - Simple Flyovers. - Cloverleaf Junction. #1. Simple Flyovers- In this case, the highway is used for fast traffic, which is made to pass over a high level by a bridge, providing foundations in both directions, and a slow walk is made to pass under. Traders therefore go through two different levels, and they miss out on the risk. Even after giving a flyover, as we have to continue to provide traffic lights at intersections under the flyover to make anyone approaching in any direction accessible all the other way. #2. Cloverleaf Junction- Cloverleaf Junction is also a type of grade separator. It was first used in America and requires a large land area. All conflicting traffic streams are avoided, so traffic can go at its own pace. This has a greater advantage than the Simple Flyover, as there is no need to weave and slow down the road. For anyone approaching a cross road there are three ways to go and four ways to approach. Therefore, there should be 4 x 3 = 12 total connectivities. In recent years Flyover Design plays an important role in reducing and diverting the growing number of traffic in big cities. Flyover Design is done in order to implement the Flyover where land acquisition costs are high and in densely populated areas. Flyover design is a complex problem, calling ingenuity and practicality while satisfying the basic security and economic requirement. The basic design philosophy that governs the construction of a flyover is that a structure should be designed to support, with a defined probability of every action that is likely to occur in its intended life span. In addition, the structure must maintain stability over time and during unprecedented action and should have sufficient firmness during its life span. India has a rich history of steel bridges and flyovers. This is usually a Flyover that passes through low terrains or at intersections of roads joining long distances with one span or multiple span constructions. The steel flyover is a good solution for long spans, construction in hilly areas, or terrain conditions. For construction of short and medium flyover, steel and composite concrete are used. In India because of the high population, most cities are saturated and traffic congestion is one of the major problems these cities are facing. The construction of flyovers is the solution to this problem. But the construction of flyovers using R.C.C is time-consuming, and will affect existing traffic, and has a low-level earthquake resistance. Construction of flyovers using steel sections can overcome this failure however its initial construction costs are high. The flyover design has three main feature elements. Abutment is the connection between the end of a flyover and a road carried by land which provides support for the final section of the flyover. A flyover is basically a bridge that crosses over another part of the road. For the construction of Flyover one should follow the following steps. - First, flyover alignment is set and pier areas and cleaning areas are available. If there are a lot of abutments or pillars, they will dig to the right depth and start driving the pile. - If the construction area has a shallow footing, then they will dig in the right depth, compact the subgrade material, and possibly build a leveling, or rat slab. - Concrete is placed on the lower part of the foundation, within the suspension, or the ground is used as a form. - A pier column or abutment concrete is then placed. - Then build the pier caps and abutments at the same time. - Then we can place the steel or precast girders, or box girders. - Then we can work on building the deck with either precast slabs or by laying a concrete deck. - After that, we can build the railroad or roadway, guardrail, and paint the road markings.
If you look outside and spot what look to be little pinecones hanging from your trees and shrubs, only one type of bug is responsible for the structures: bagworms. Inside the pinecone-like bags you'll find either one bagworm or hundreds of little eggs. The insects can defoliate and severely damage and even kill plants. When spring arrives, eggs that female bagworms laid in fully-developed bags during the previous fall hatch. The larvae that emerge begin feeding on the host plant by crawling to and eating leaves. Some larvae suspend themselves on silk strings and get blown by the wind to new plants or new areas of the host plant. Each then creates a little bag made of silk over its abdomen. As a larva feeds, it adds piece of leaves and twigs to its bag, making it larger and larger throughout the spring and summer. Towards the end of summer the larva has an impressive bag that measures around 2 inches in length. It then wraps the top of the bag around a twig using silk. The bag hangs down, looking similar to a pinecone. Purpose of Bag A bagworm's pinecone-like bag serves one primary purpose: protection. It enables the female's eggs to properly develop over winter and keeps insects and other predators away. When larvae begin feeding and creating bags of their own, they withdraw into them when they rest or feel threatened. Once they hang their bags from twigs in the fall or at the end of summer, larvae retreat into them to molt. Later in fall, males enter the world as fully grown moths. The females, which do not evolve into moths, remain in their bags, waiting for males to find and mate with them, and then the process begins all over again. Bagworms aren't pretty, especially when they create bags on trees that look quite strange with pinecone-like structures hanging from them. But aesthetics aside, they can pose serious dangers to trees and shrubs. The University of Kentucky College of Agriculture, Food and Environment points out that older larvae can strip needles from evergreens and obliterate whole leaves of deciduous trees and plants. The university further notes that several years of heavy infestation can lead to plant death. Preventing bagworm infestation calls for removing the bags that hold unhatched eggs. Iowa State University's Integrated Pest Management Program suggests cutting them down with scissors and disposing of them before they hatch—by about early spring. If the larvae have already hatched, you can use insecticides to kill them. Common insecticides used to treat bagworm infestations include those that have spinosad, carbaryl, acephate, permethrin or malthion as the main ingredient. Always follow the manufacturer's directions to the letter when using insecticides, and if you're unsure of which insecticide to use, contact your local county agricultural extension office. Located in Pittsburgh, Chris Miksen has been writing instructional articles on a wide range of topics for online publications since 2007. He currently owns and operates a vending business. Miksen has written a variety of technical and business articles throughout his writing career. He studied journalism at the Community College of Allegheny County.
This theme is based on the world around us, both historically and in terms of geography. Children can explore their local area and historical events and famous figures. All pupils: Think about and then mindmap all of the great things about your local area. Consider what makes the area you live in attractive for different kinds of people. Try and use some geographical vocabulary to describe some of the features of where you live. Design and create a poster to persuade the reader to want to move to your area. Completing the activity: Year 3 & 4 - please also answer the following questions using the audio tool on Seesaw Years 5 & 6 - please also do the following and screenshot before uploading on Seesaw: Useful websites and resources: Screenshot or video your project and send it through to your class teacher via Seesaw. Wow them with your efforts!
I do organic chemistry and hopefully this might help you in some way. So, we need to have the following basics to understand organic chemistry - Reaction intermediates (C+, C-, C:etc.) - Effects (Inductive, electromeric, mesmeric etc.) - Types of organic reactions.(Substitution, Elimination, Addition, Condensation & Rearrangement reactions) Unless u have the above basics we cannot understand the concepts in organic chemistry.. Coming to the trick in organic chemistry which covers majority of reactions, you can follow in the following way.. A-A-A-A four A formula First A is Alkane Second A is Alcohol Third A is Aldehyde Fourth A is Acid So the above conversion from Alkane to Alcohol to Aldehyde to Acid can be done simple oxidation reaction in each step Oxidising agents are mild ones which are CrO3/MnO2 Whereas if you want to convert Alkane to Acid or Alcohol to Acid we can do strong oxidation with K2Cr2O7/KMnO4 A-A-A-A four A formula once again Note: We can never convert an acid to aldehyde by reduction So Aldehyde to Alcohol to Alkane can be converted in each step by mild reduction Reducing agents can be LiAlH4/NaBH4. Tip : For finding acidic and basic character order which is the most important part of organic.. - A donating group always decreases acidic nature and increases basic nature. - A withdrawing group always increases acidic nature and decreases basic nature.
Most simply stated, empathy is the ability to put oneself in another’s shoes – and also the willingness to respond to the person’s needs. It’s one of the most important components of a happy, healthy relationship. Lack of empathy is a common problem with couples and can stem from never learning how to be empathetic from their primary caregivers or other important people in their lives. The good news is – it can be taught. Here are 5 tips to start practicing empathic communication when discussing a difficult subject: - Listen without interruption as your partner describes his/her feelings about the subject. Maintain eye contact and pay close attention. - Pause and imagine how your partner might be feeling. - Reflect back what the partner has said in regards to their feelings like, “What I’m hearing you say is that you’re upset because…” - Validate their feelings such as, “I understand how you would be upset…” You don’t have to get why – just allow them to have their feelings. - Offer support by saying something like, “I’m sorry you’re feeling this way, let’s figure this out together.” If an apology for your behavior is appropriate, do so. A hug or loving physical touch might also be another connecting and supportive action. If you’re having a disagreement with your partner, sometimes it’s hard to get to a place of empathy for each other. But if you slow things down and get out of your anger or hurt long enough to imagine what the other is feeling – you’re on your way to empathetic communication, one of the elements of a loving, emotionally safe and securely attached relationship.0
We all know that our hearing keeps us connected to the world. Without our hearing, it is easy to become disconnected and isolated from others, a grave concern for the senior population. There is an abundance of attention in research and publications looking at and reviewing the correlation between hearing loss and brain health. Understanding and preventing hearing loss Our ears are both simple and complex. While there are only three different parts, each plays a crucial role in our hearing. There are four types of hearing loss, and each one correlates to an area, or areas, of the ear that suffers damage. It’s vital that we guard our hearing, and take preventive measures against its loss. Here are the causes that we see and treat more often at the Silverstein Institute: Presbycusis is the hearing loss from degenerative changes of aging on the inner ear. The middle ear is the area that houses the eardrum and the 3 ossicles (tiny bones of hearing). When one of these bones is fixed, it blocks the travel of sounds to the inner ear. Known as otosclerosis, it is surgically correctable. One can use a hearing aid as well. As glaucoma causes damaging pressure to build up in our eyes, Meniere’s disease is when there is damaging pressure in the inner ear. There is an array of debilitating symptoms that comes along with this inner ear disease, including vertigo affects, hearing loss, and tinnitus. Any ear infection requires medical attention, especially an infection of the middle ear that is commonly known to result in hearing loss. The earlier an ear infection is caught and treated, the better chance of avoiding any loss of hearing. How healthy hearing keeps your brain healthy When we talk about brain health, there are so many different things that affect the health of our brains. As we age, our brain function begins to deteriorate over time. We must do everything we can to keep our brains in the best of health, and hearing plays a big part in good brain health. Important for Communication and Interaction No matter our age, being able to listen, communicate, and interact plays a vital role in our well-being. As we age, the ability to hear what our family, friends, and physicians have to say helps us stay connected. Keep the Brain Active and Busy Hearing is essential to keeping the brain working to take in messages and respond. Whether having a conversation, listening to the radio, or watching the television, the brain stays active, processing what is seen and heard. Brain Degeneration and Cognitive Decline With severe hearing loss, it’s easy for people to withdraw and not communicate. This can allow the brain to degenerate, more and more, overtime. Treating hearing loss will not prevent cognitive disorders, such as dementia or Alzheimer’s. However, reviewed by Harvard Health Publishing, certain factors play a part in “protecting against cognitive decline.” While it’s up to an individual to exercise regularly, consume a healthy diet, and get adequate sleep, our hearing plays a vital role in “mental stimulation” and “social contacts.” First Physicians Group Silverstein Institute, locations in Sarasota, Longboat Key, Lakewood Ranch and Osprey, specializes in the diseases of the Ears, Nose, and Throat. Our entire staff is here to not only offer compassionate care, but we’re also here to offer the highest standard in medical treatment for loss of hearing, and to help you maintain good brain health.
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In order to understand tendonitis, you must know what a tendon is and what role it plays in the body. When a muscle contracts, it pulls on a bone to cause movement. The structure that transmits the force of the muscle contraction to the bone is called a tendon. A tendon is a tough, yet flexible, band of fibrous tissue that provides structure by connecting your muscles to the bones. The tendon is very important in helping the skeletal muscles move your bones, thus enabling you to walk, jump, lift, and move in many ways. Tendons come in many shapes and sizes. Some are very small, like the ones that cause movements of your fingers, and some are much larger, such as your Achilles tendon in your heel. When functioning normally, these tendons glide easily and smoothly as the muscle contracts. However, if the tendons become inflamed for a variety of reasons, the action of pulling the muscle becomes very irritating. Thus, if the normal smooth gliding motion of your tendon is impaired, the tendon will become inflamed and movement will become painful. This condition is called tendonitis, which literally means inflammation of the tendon. Causes of Tendonitis There are hundreds of tendons scattered throughout our body, but it tends to be a small handful of specific tendons that cause problems. These tendons usually have an area of poor blood supply that leads to tissue damage and poor healing response. The area of a tendon that is prone to injury is called a “watershed zone,” an area where the blood supply to the tendon is the weakest. In these watershed zones, the body has a hard time delivering oxygen and nutrients necessary for tendon healing. This is why we see common tendon problems in the same parts of the body. If you believe you may be suffering from tendonitis or other issues, please contact our office to discuss your treatment options, or request your appointment here.
LA 6.1 Debating the Value of High Stakes Testing |Learning Outcome||Pedagogical Intent||Student Position| Acknowledge and follow local, state and federal laws and policies as they pertain to ELLs and their assessment. TA: 20 Minutes Teachers can prepare English Learners for high stakes testing through learning about kinds of test questions and helping students understand the process. Students have learned about and developed expertise in classroom-based assessment of students. Now they consider high stakes testing that is external to the classroom. They will explore the benefits and draw-backs of high stakes testing as they consider pro and con statements from literature in the field. 1.Working in your PLC group, share how your opinions about high stakes testing have shifted based on HW 5.4. 2.Next you will engage in a debate about high stakes testing within your group. Two of you will speak to the pros of high stakes testing and the other two will speak to the cons. 3. Take a few minutes for the partners to confer. Develop the assertions you want to make and note details you think will support you in responding to the assertions and defense the opposite team makes. 4. Begin with each group making their initial assertsion--the pros make their assertion followed by the cons rebutting their assertion. 4.Second the cons make their assertion and then the pros rebut their assertion. 5. Using post-it notes, the pros in your group write a sentence summarizing their position, and the cons write a sentence summarizing their position. 6.Post these on the charts provided by the facilitator and quickly review comments other pro and con groups have made.
International Human Rights Day is observed on December 10. It was the day when the United Nations Universal Declaration of Human Rights was adopted in December 1948. • This day has been celebrated ever since the day the UN adopted the Universal Declaration of Human Rights in 1948. • For the first time, 48 countries celebrated this day with the UN General Assembly. • In 1950, the General Assembly passed resolution 423 (v) and urged all countries to adopt it. • In December 1993, it was announced by UNGA to celebrate it annually. What are Human Rights? National Human Rights Commission (NHRC) Human rights law came into existence in India from September 28, 1993. This Commission has made its recommendations to the Government to protect the rights of ordinary citizens, children, women, elderly human rights, and people of the LGBT community in the country. The Government has also implemented appropriate amendments in the Constitution, following several recommendations made by NHRC. The theme of this year is ‘Recover Better – Stand Up For Human Rights’. Human Rights Day is an opportunity to reaffirm the importance of human rights in re-building the world we want, with global solidarity, interconnectedness and shared humanity. Basic Human Rights According to the Universal Declaration of Human Rights, here are the basic rights available to everyone: - Right to life - Right to liberty - Right to security of people - Right to be free from slavery - Right to be free from involuntary servitude - Right to be free from torture - Right to be free from cruel, inhuman, or degrading treatment or punishment - Right to recognition everywhere as a person before the law - Right to equal protection of the law - Right to an effective remedy by the competent national tribunals for acts violating the fundamental rights granted him by the constitution or by law - Right to not be subject to arbitrary arrest, detention, or exile - Right to a fair and public hearing by an independent and impartial tribunal - Right to be presumed innocent until proved guilty according to law in a public trial at which one has had all the guarantees necessary for one’s defense - Right to be free from arbitrary interference with one’s privacy, family, home, or correspondence - Right to be free from attacks upon one’s honor and reputation - Right to the protection of the law against such interference or attacks upon’s one’s privacy, honor, or reputation - Right to freedom of movement and residence within the borders of each state - Right to leave any country, including one’s own - Right to return to one’s country - Right to seek and to enjoy in other countries asylum from persecution - Right to a nationality - Right to change one’s nationality - Right to marry - Right to find a family - Right to free and full consent in choosing one’s spouse - Right to freedom of thought, conscience, and religion - Right to freedom of opinion and expression
Typically, when you speak of motor boats your attention is directed into something moving on water. They are vessels powered by combustion engines and are propelled through water. The propulsion could either be a jet propulsion or simply propeller motion. The mechanism used in jet propulsion is water suction-expulsion where water is sucked through the front then is expelled at the rear thereby achieving a thrust which causes the boat to move. In propeller motion, the propeller allows the boat to move as it cuts water while spinning continuously. Features And Uses Certain features and uses distinguish motor boats from one another. They differ according to the four main types of boat motors. They also have relatively different boat bottom paint depending on their design and the designer’s choice of colors. Types Of Motors Note that the term powerplant is used when the engine is fitted within the boat. Otherwise, if it’s a removable part, it’s called an outboard. Certain motor boats are built according to the following features: - Inboard/Outboard Motors With an inboard/outboard motors, the combustion engine (internal) is installed within the boat while the propeller and gearbox are outside. Generally, inboard/outboard motors contain a powerplant and an outboard. - Inboard Motors Compared to inboard/outboard motors, inboard motors are mounted slightly lower and farther forward. The inboard is configured in two ways, the V-drive and the direct drive. The difference between the two configurations lies in the placement of the powerplant and the propeller shaft. The direct drive has its powerplant mounted at the middle of the boat and its propeller shaft at the back. On the other hand, the V-drive has its powerplant mounted at the back and the propeller shaft going to the front making a V towards the rear. - Outboard Motors Outboard motors are clamped onto the transom. The motor steers the boat by pivoting on its mounting making the boat turn into the opposite direction. There are various sizes of outboard motors depending on its capacity and design. - Jet Motors Jet motors are special motors that use engine to move the boat. The engine pumps water through a nozzle causing it to pivot thereby steering the boat. There are basically two types of engines for motor boats, the two-stroke and the four-stroke engines. The two-stroke engine is lighter, easy to repair, and cheaper. However, it can be noisy and releases a significant amount of smoke. The four-stroke engine, on the contrary, is quiet, smooth, has less smoke emissions and relatively good fuel efficiency. Its disadvantage, however, is on its heavy weight and greater repair costs. Motor boats are perfect for people who love adventures simply because the vessels can take them to places instantly and with a good view of their surroundings. Motor boats are often used on lakes, rivers, and seas without the need to worry over and wait for the right wind conditions. Available Types And Popular Manufacturers Several manufacturers specialize on certain types of motor boats. The following list may significantly help you out if you plan to purchase or use one. - Fishing Boats - Bass Boats - Cabin Cruisers - Deck Boats - Wakeboard Boats - Jet Boats - Pontoon Boats Limit not yourself with this article. There is more online to know in-depth about motor boats.