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Applying new math, Kristina Crona, an American University assistant professor who researches in the area of mathematical biology, and her colleagues show how ranking pathogen mutants can help scientists understand how mutants evolve to resist drug treatments. This line of research could have implications for the treatment of diseases that can resist drug treatments, such as HIV and malaria. The researchers show that rank order is one way to identify complex genetic interactions. Conventional methods for identifying complex gene interactions rely on precise measurements of the genetic fitness of mutants. However, fitness measures are not easily applied, and they are not always reliable. By contrast, the rank order method works, even if the data is incomplete. Crona uses "Dyck words," a formula named after the 19th-century German mathematician Walther Franz Anton von Dyck, to match up the genotype with letters. Letters "x" and "y" are assigned to the pathogen mutants. Single and triple mutants correspond to "x," and unmutated, double and four-tuple mutants correspond to "y." The odd number of mutations produce "x" and even numbers produce "y." The mutants in the order are ranked from high to low fitness. "From left to right, we count x's and y's. If there are always more x's, or the same numbers of mutants are x's, then what you get is a Dyck word. This means one can see that one is dealing with a complex gene interaction," Crona said. Complex genetic interactions involve three or more mutations in a pathogen. It is in complex genetic interactions when pathogens have higher fitness and evolve dangerously, such as a pathogen that's strong enough to resist antibiotics. The researchers identified complex gene interaction involving three or more mutations for HIV; a malaria-causing parasite; the type of fungus that causes black mold on fruits and vegetables; and a family of genetic mutations that contribute to antibiotic resistance. Crona began thinking about rank orders while working with biologist Miriam Barlow on the problem of antibiotic cycling, by which hospital doctors rotate different antibiotics to thwart patient infections. Trying to help doctors maximize antibiotics' effectiveness, the team created software called "Time Machine". The study findings were published in the journal eLife. Time machine uses probabilities and rewinds the evolution of bacteria to verify treatment options for 15 antibiotics used to fight common infections. Crona noticed that rank orders were surprisingly robust. The numbers came out a bit differently in every experiment, but the most dangerous mutants were always dangerous, and harmless always harmless. In medicine in the future, doctors may be able to take advantage of complex gene interactions when they develop treatment plans. Rank order can help with cutting off the chain of events in the evolution of a dangerous pathogen. Preventing lesser, intermediate mutants could stop a pathogen's evolution, Crona said.
Early History Part III With the age of Hellenism, opened by Alexander’s victory over the Persians, the autocracy of the Greek Poleis came to an end: Political power now emanated from the monarchically ruled empires of the Diadochi and the mother country, with Athens as its center, indicated its hegemonic position the periphery from: to the Ptolemies in Egypt, the Seleucids in Syria and the Antigonids in Macedonia. At the same time, however, the traditional political culture spread by leaps and bounds across all Mediterranean countries and in the east as far as India; a large-scale civilization arose, a mixture of Greek and oriental elements. The lingua franca was Greek, the so-called Koine (“common language”) derived from the Athens dialect. A new cultural center was built in Alexandria, generously endowed by the Ptolemies. During Hellenism, the third major epoch of antiquity was gradually being prepared: the Roman Empire. Rome rose in the 3rd and 2nd centuries BC. BC to the leading power: At that time, after the unification of Italy, the elimination of Carthage, the only serious competition, succeeded, and the Diadochian empires fell one by one to the Romans; last, after the battle of Actium (31 BC), that of the Ptolemaic Cleopatra ruled Egypt. The most important turning point in Roman history coincides with the transition from the Hellenistic era to the imperial era. The republican state system had proved incapable of satisfactorily administering the growing empire; The dictatorship of Caesar and subsequently the permanent monarchical system of Augustus emerged from a century of internal wars. The imperial era In contrast to the extremely dynamic development during the last century of the Roman Republic, the imperial period, the period of the Pax Romana, had a relatively static appearance. The half millennium until the migration of peoples and the fall of the western half of the empire shows only one major turning point: the imperial crisis in the middle of the 3rd century AD, which led to the still relatively liberal constitution, Augustus had created the so-called principate (from Latin princeps, “first man”, an expression only suggestive of the emperor’s outstanding position), was replaced by the dominate, a strictly absolutist and dirigistic coercive system. This also meant an epochal turning point for the spread of the Latin language: At that time the great expansion movement came to a standstill, which took place during the principle of the whole of the West, i.e. H. Africa, Spain and Gaul, as well as the Alpine and Danube regions. Christianization and the fall of antiquity According to Healthvv, the turning point of the 3rd century AD has recently led to the thesis that the next phase, late antiquity, already has closer ties with the following period, the early Middle Ages, than with the previous one. Since the territory of the empire survived the crisis undamaged, only internal developments can be cited for this, in particular the spread of Christianity, which rose to become the only legal religion in the course of the 4th century. At the same time, the church adopted the nimbus of the capital Rome, and its organization proved to be so stable that it survived the collapse of the state administration in the chaos of the German trains. In the 5th century the processes began which brought the physical end to the Mediterranean world of antiquity. From the dissolving Imperium Romanum, three powers emerged from the interim stage of short-lived Germanic rule: the Islamic-Arab states in the south and south-west (in Persia, Armenia, Arabia, Egypt, Africa and Spain), the Frankish Empire in the north and east or Byzantium in the east. The former masters of the world, the Romans, disappeared as an ethnic greatness in the course of the 6th and 7th centuries, and with them their language, Latin; this only lived on – thanks to the church, then also thanks to the state – as a laboriously learned second idiom of Romance and Germanic speakers. The epochs of cultural history The three main epochs of antiquity are derived from the political realities; the periods of cultural development, especially those of literary and art history, do not always coincide with this. The Christian literature of late antiquity z. B. was essentially independent of the fortunes of the Roman state. In addition, the phase shift mentioned is particularly noticeable in the area of intellectual history; when Roman literature reached its classical height in the Ciceronian-Augustan period, the Greek sister had already passed its (“modern”) late phase. From a cultural and historical point of view, the category of antiquity is largely nothing but a framework that encompasses the succession of the inventing Greeks and the imitative Romans. The Greek culture With the Greeks, however, the cultural-historical epoch boundaries essentially coincide with the political ones. The classical period coincided with the general heyday after the Persian Wars, and later, as in the political as well as in the cultural area, the reigns of Alexander the Great and Augustus marked deep cuts. In addition to the epic and the didactic poem (Hesiod), the archaic period produced a great variety of lyrical forms in literature; however, apart from Pindar’s songs of victory, not much more of this wealth have reached posterity as fragments. The epic and didactic poem thematize mythology, as do the narrative parts of lyric poetry; there, moreover, the author’s experiences are poetically processed. – When the temple was built, the Doric and Ionic styles developed into their canonical form; the large-scale sculpture gradually breaks away from its strict Egyptian models.
NIAID investigators and colleagues from Columbia University Medical Center and St. George’s University of London have charted the emergence of a new strain of Staphylococcus aureus (S. aureus) bacteria that transmits efficiently among humans. Scientists have determined that this new strain primarily infects the skin and soft tissue, but it can cause more severe disease. A methicillin-resistant S. aureus (MRSA) strain known as livestock-associated (LA)-ST398 is a cause of severe infections in people in Europe who have close contact with swine, but the bacterium does not transmit well from person to person. More recently, a variant of LA-ST398 that presently is susceptible to methicillin has emerged as a significant cause of human infections in several countries, including the United States, Canada and China. The new strain, named ST398-NM, has adapted to transmit more easily among humans. By analyzing and comparing the genomes of LA-ST398 and ST398-NM, the study, led by Anne-Catrin Uhlemann, M.D., Ph.D., at Columbia, charted several ways in which the bacterium has adapted to its hosts. For example, they learned that the human-adapted strain ST398-NM contains human-specific immune evasion genes, whereas the livestock-adapted strain does not. They also found that ST398-NM adheres well to human skin, thus increasing its ability to colonize and infect people. The study authors say it is possible that the emerging ST398-NM strain could acquire genes making it resistant to methicillin. Scientists at the NIH National Institute of Allergy and Infectious Diseases and their colleagues plan to continue global surveillance of the strain, paying close attention to its molecular adaptations. This new study further underscores the need for vigilance in surveillance and detection of S. aureus.
Worms are invertebrates with long, soft bodies and no hard skeleton. Their shapes are varied, and they range in size from microscopic to 75 feet in length. Scientists have classified worms into more than 15 phyla. The phylum Annelida contains the segmented worms. Annelida is further divided into three subclasses: Oligochaeta, Hirudinea and Polychaeta. Thousands of species of segmented worms comprise these three subclasses. All species contained in the Annelida phylum are segmented to varying degrees. The transecting segments divide their bodies into subdivisions. Each subdivision houses the organs for specific bodily functions such as the circulatory, nervous or digestive systems. Segmentation, also called metamerism, localizes muscle contraction, allowing body movement to attain ultimate proficiency. Hydrostatic pressure across each segment permits the annelid's bodies to bend and contract without collapsing. Oligochaeta is composed of earthworms and related species. Earthworms have smooth, mucous-coated skin, usually in hues of gray, white, pink or reddish-brown. Their bodies exhibit distinct segmentation. Each segment is covered with stiff, microscopic hairs that enable movement. They vary in size from less than one inch to more than six feet long. Most species are hermaphroditic. Hundreds of species inhabit moist soil environments on every continent, feasting on decaying plant material and roots. Blind and deaf, they communicate through touch and taste, and are able to sense light and vibrations. Hundreds of species of leeches comprise Hirudinea. Leeches have flat, dark-colored bodies with suction cups at each end. Some species have one or more pairs of eyes, and many possess sharp teeth or strong, crushing jaws. These hermaphroditic worms range from less than one inch to almost 10 inches in length. They inhabit freshwater, oceans and moist soil all over the world. Deaf and poorly sighted, they hunt and communicate using profoundly heightened senses of touch and taste. Infamous as parasitic blood-suckers, many leeches feed on fish, waterfowl, turtles or other vertebrates. However, not all leeches feed on blood. They are predators that consume worms, snails, fish and other invertebrates. According to the Smithsonian National Museum of Natural History Department of Invertebrate Zoology, Polychaeta is the largest Annelida subclass. It's divided into 13 families that include, among others, fireworms, fan worms, rag worms, paddle worms, spaghetti worms and bamboo worms. They're primarily marine species, inhabiting oceans all over the world. Like their Annelida counterparts, their segmented bodies house their circulatory, digestive and nervous systems. However, in contrast to other annelids, they possess well-developed heads, eyes, appendages and sense organs. They further differ from other annelids in that they do not mate. Fertilization is external, meaning eggs and sperm are released into the water and unite independently of the originating organisms. Ryan McVay/Photodisc/Getty Images Yvette Sajem has been a professional writer since 1995. Her work includes greeting cards and two children's books. A lifelong animal advocate, she is active in animal rescue and transport, and is particularly partial to senior and special needs animals.
While melody and harmony are all important parts of any song, Jazz emphasizes something that is so important to the development of music: improvisation. In Jazz, each performer takes a turn experimenting with different notes to create an overall new sound experience. Every time they step out on stage, Jazz musicians may perform songs that no one has ever heard before, and no one will hear again. Since the beginning of Jazz, people have been using its improvisation factor to express how they feel. In the 20th century, New Orleans became the hub of Jazz music. As a port city, New Orleans hosted a tremendous amount of people arriving from all over the world. These people, along with area locals, would come together to listen and perform music as a way of communicating and assimilating into their new culture. However, its earliest roots have been linked to Africans enslaved in the United States who had been using this form of music as a means of passing the time and keeping their culture alive. While working in the fields, they would sing spirituals to “express not only devotion and faith but [their] desire for freedom from the white man’s subjugation.” By the time slavery was abolished, early Jazz music had made its way along the South. When it arrived in New Orleans, elements from African and European music molded Jazz into what it is today. Jazz is said by some to be the only true American form of music. What started off as a totally new style has transformed into many forms of genres in the American culture. Rock, R&B, Hip-hop, Pop and other genres have been influenced by Jazz. Jazz rhythms and harmonies have been featured in styles of music that produce a sway rhythm, like R&B or Latin styled tunes. Jazz has contributed a great deal to the style of Hip-hop music. Some critics have said that Hip-hop is just a way to “ruin” or “vulgarize” Jazz, but what those people don’t understand is that the artists of today are taking the influences of past Jazz musicians and adding their own new elements to create new music. Hip-hop takes all the elements that Jazz contains, like infectious rhythms and intense melodies, and develops it into something new. Just like with Jazz, improve-or freestyling-is a lauded skill in hip-hop that allows rappers to express their thoughts and feelings on the spot with their music. It’s not uncommon for “battle rappers” to engage in freestyle battles and ciphers for sport. It all comes back to improvisation. Whether you’re playing Jazz or rapping your own lyrics, you are able to communicate your feelings through music, which is an enlightening experience. As George Gershwin once said, “Life is a lot like jazz. It’s best when you improvise.” Music has a way of communicating with people who may have little or nothing in common. Two people who don’t speak the same language, or have the same culture, or look the same, can feel emotions and enjoy a song in their own unique way. Jazz is one of those genres of music that everyone who hears it experiences something, whether or not they are alike. Jazz has played a big part in America’s culture and history, as a form of expression and a way of bringing people together. What began as a way to escape reality, turned into an expression of one’s self. We thank the Black communities of America for creating jazz; music that can unite people of different races and ethnicities, allowing us to come together to enjoy. Jazz music and its offspring are evolving every day. While it’s important to learn from and remember the great musicians of the past, we also need to look forward and see what the future will hold for “America’s true form of music.”
With long-haul trips to Mars an ever-more realistic possibility, scientists are thinking about what the impact of months-long space flight will be—both on astronauts' behavior and their physical health. Space is full of radiation, and there's clearly some risk associated with spending months speeding through that sort of environment. According to one new study, long-term exposure to space might damage proteins in the brain, reports Adrienne LaFrance, at the Atlantic. The study looked only at the brains of rats, but found that exposure to high-energy particles could lead to several cognitive defects, including memory problems and slower reaction times. Some of their findings, however, are perplexing. LaFrance writes: But the strange thing scientists found is that deep-space conditions don't affect everyone the same way. About half of the rats tested emerged from the test entirely unaffected. The others began showing symptoms about seven weeks after exposure to space-like conditions. And once impairments appeared, they never went away. (Some rats showed improvement over time, however, raising the question of whether recovery is possible.) These findings held true even at very low radiation exposure levels, RedOrbit adds. Since the study did not examine human subjects, the researchers can't say whether, or how, their results apply to astronauts. If there is some connection, though, it might be possible to identify biological markers for susceptibility to these types of problems, LaFrance reports. Then, this physiological trait could be added to the already lengthy list of characteristics—from specific heights to eyesight requirements—that astronaut applicants must meet in order to be considered for the position.
\|Traditional Storage of Yams and Cassave and its Improvement (GTZ)\| Cassava is a plant of the new world which originates in the northeast Brazil. Central America is assumed as another source (ONWUEME, 1978). Having begun with these two regions, cassava is now cultivated in all tropical regions of the world. In contrast to yams, mere is only one species of cassava bearing the scientific name Manihot esculenta Crantz and belonging to the family of the Euphorbiaceae. There is a wide range of cassava varieties. Individual varieties can be recognised by the leaf and root form, the duration of vegetation, the yield and the content of hydrogen cyanide. The latter constitutes the difference between the sweet and the bitter cassava. The bitter varieties of cassava have a high hydrogen cyanide content which can amount to up to 250 mg pa kg fresh root (GRACE, 1977). To avoid poisoning, the roots have to be detoxified before consumption. The vegetation period for bitter cassava varieties lies between 12 and 18 months. After ripening, the roots can be left unharvested in the soil for a long period and will not spoil (ONWUEME, 1978). The sweet cassava varieties only contain low quantities of hydrogen cyanide so mat detoxification prior to eating is normally not necessary. The vegetation period is relatively short at 6 - 9 months. The roots of this variety rot quickly if they are left in the soil after maturity. The content of hydrogen cyanide is not constant according to the varieties, but is subject to fluctuation due to the environment. For this reason, the content of hydrogen cyanide is unsuitable as the only criterion in defining the varieties of cassava (ONWUEME, 1978). Cassava is a perennial plant. Apart from for purposes of research and breeding, propagation is exclusively vegetative. In contrast to yams which are propagated via the tuber, the cassava can be reproduced by cuttings taken from the stalks of the plant. As the stalks, in contrast to the root, are used neither for consumption nor other economic purposes, the cost of propagating cassava where planting material is concerned, is practically zero.
Power of the Question Lesson 2: Research-Based Questions In their journals, ask students to free-write in response to these questions: Think about the professional journalist you watched or listened to for homework last night. How did he or she use naïve questions? What kinds of responses were elicited from naïve questions? Were naïve questions useful? How? After students have had time to respond, ask students to share their experiences with the homework assignment and reflect on the use of naïve questions in the media. Post some responses on a chart that can be used for future assignments. Ask students: How do you think professional journalists decide which questions to ask? What kind of research do journalists have to do in advance to be able to write good questions? Introduce the research section of the Simon video, which features the role of research in question formation. Ask students to listen for Simon’s explanation of how research can be used to develop questions. Encourage students to take notes during the video. After watching the video, have students discuss Simon’s views on using research to develop questions. What examples does Simon provide? (You can watch the entire Simon video here.) Use one of Simon’s radio interviews to hear more examples of how he uses research with his interviewees: - Example: In his interview with Joan Allen, Scott Simon uses research to ask Allen about her father’s livelihood and how it affected her career choices. - Jeremy Irons, Joan Allen Star In ‘Impressionism’ (March 07, 2009) - Example: Simon interviewed Kinan Azmeh about his life and his music. He asked a simple, yet easy-to-overlook question about the guest’s decision to pick up the clarinet. His guest responded with an incredibly detailed story about his decision. How can research be used to elicit peoples’ stories? - Kinan Azmeh: A Syrian Frequent Flier With Clarinet In Hand (March 07, 2009) - Example: In July, Simon interviewed Tanya Tucker about early start in the music business after her release of a new album this summer. Without Simon’s knowledge of her history, he would have missed the importance of sharing with the audience something Tucker assumed everyone knew about Mel Tillis and the beginnings of her career. - Tanya Tucker: Living In A Country Song (July 11, 2009) As students are listening to the radio interviews, have them list examples of times when Simon uses research in his questions to build conversation or elicit stories. After listening to one or more of these interviews, reflect on Simon’s use of research. How does he use research to improve his questions and the overall quality of his interviews? Place students in small groups. Assign each group an author or historical figure that connects to the class’ curriculum. Choose individuals who are relatively unfamiliar to students. Ask students to develop at least five interview questions for this person. Do not provide any further information about the individual at this time. After students have developed their initial questions, give each group the chance to learn more about this author or historical figure. Depending on time, teachers may give each group a dossier or biography of this person, or allow students to research their selection on the Internet. Ask students to revise and improve their initial questions to reflect the knowledge they gained through their research. Ask students to write three additional questions after researching the person. Ask each group to write one of their initial questions on the board. Beneath this initial question, ask the group to share how they revised their question to incorporate the research they learned about the person. Share each group’s experiences. Compare and contrast the quality of questions developed with and without the knowledge gained through researching the individual. Pass out the following writing prompt to students: In school, we tend to think of using research to answer questions, but Simon is encouraging us to use research to write and create good questions. Think of a time when you have done research to help you ask a question (English class for research paper, American Studies and Film for interviews). Write at least one paragraph describing the research you did, the question you asked, and the response you got. The lesson below is from The New York Times Learning Network online, September 26, 2007 After students have been seated, they respond in their journals to the following question (written on the board prior to class): “Imagine a world leader who had gone on record as labeling the Holocaust a ‘myth,’ calling for Israel to be ‘wiped off the map,’ denouncing homosexuality, and who was suspected of harboring a secret nuclear weapons program, is in town for a diplomatic meeting. Do you think this person should be invited to speak publicly? Why or why not? Support your position.” Allow students several minutes to write, and then have several volunteers share their responses with the class. Ask them to which current world leader the description in the journal prompt refers. If students are unfamiliar with Mahmoud Ahmadinejad, you may wish to spend a few minutes offering a brief overview of his policies and Iran’s role in the context of current world affairs. For more information on Mr. Ahmadinejad, see The New York Times “Times Topics” page . As a class, read and discuss the article “Ahmadinejad, at Columbia, Parries and Puzzles” focusing on the following questions: - Why did Iran’s president, Mahmoud Ahmadinejad, speak at Columbia University on September 24, 2007? - How did Columbia University President Lee C. Bollinger introduce Mr. Ahmadinejad? - What are some examples of Mr. Ahmadinejad’s controversial opinions? - Why, according to the article, was Mr. Ahmadinejad in New York City at this time? - What do you think Mr. Ahmadinejad’s response to Mr. Bollinger’s introduction as a “vaccination to the students and faculty” means? - How do you interpret Columbia University audience’s response to Mr. Ahmadinejad’s remarks about the “Palestinian issue”? - What conclusions can you draw about Mr. Ahmadinejad based on this article? What conclusions, if any, can you draw about Columbia University? Original Link: http://www.ypress.org/news/researchbased_question Ask students to imagine that your school will be hosting a visit from a yet-to-be-disclosed controversial world leader (other than Ahmadinejad). Have them brainstorm a list of potential leaders as you write them on the board and on slips of paper. Though students’ understanding and opinions of controversial figures may differ, examples might include: Kim Jong Il (North Korea), George W. Bush (United States), Nicholas Sarkozy (France), Hugo Chavez (Venezuela), Fidel Castro (Cuba), Vladimir Putin (Russia), Ehud Olmert (Israel), Robert Mugabe (Zimbabwe), Mahmoud Abbas (Palestinian National Authority), Pervez Musharraf (Pakistan), Nuri Kamal al-Maliki (Iraq), among others. Next, divide class into pairs and have each pair select a current leader on one of the slips of paper. Encourage students to keep their assigned leaders to themselves. Using all available classroom resources, students spend 20-25 minutes researching and taking notes on their leaders’ biographical information, leadership history, general worldviews, and examples of recent decision-making or political actions. Ask students to consider what specific policies their leader has implemented, and how they impact his country. How do the positions and opinions of this person on key issues affect his country’s relations with the rest of the world? After students have completed their research, direct them to spend the remainder of the class period formulating five interview questions to pose to their assigned leaders based on the information they have gathered. Questions should be challenging and should go beyond the personal or anecdotal to cover a variety of specific events and/or policies. For example, asking a leader under what circumstances, he would (or has) authorized the use of torture, would be considered a relevant question; a question about the leader’s family or personal life would not. In addition, pairs should also write a two- to three-sentence rationale for each question they develop, explaining the context and citing a specific news source related to the subject. At the end of class, each pair presents one interview question without mentioning the assigned leader’s name, and challenges the class to guess this person’s identity. Before the end of the period, have students revisit Columbia University President Bollinger’s introduction of Mahmoud Ahmadinejad. Described in the article as “a 10-minute verbal assault,” Mr. Bollinger’s opening remarks set the tone for the September 24, 2007 event. Ask students to consider the tone they would like to convey if their assigned leaders were to make an appearance at school. Would they pointedly challenge them on specific issues in their introductions, or would they present neutral background information and let audience members draw their own conclusions? Why? For homework, each student writes a two- to three-paragraph introduction for his or her assigned world leader. In a following class period, students compare and peer edit their introductory statements with their partners to create their respective final drafts. They then present their introductions, along with all five questions, for the entire class to consider. This lesson may also be used in the history classroom to address controversial leaders of the past.
This chapter reviews some of the research findings about learners’ ideas about atomic structure and other chemical structures Introducing some related classroom instruments included in the companion volume. The structure of the atom During their secondary education, students are expected to learn about the structure of the atom, or - more correctly - to learn about a particular model of the structure of the atom. The usual model of the structure of the atom met at this level consists of the nucleus at the centre of one or more shells of electrons. The electrons are usually shown as being placed on these circular shells. Although this model is perfectly appropriate at this level, those students who take their study of chemistry further will need to accept more detailed models. It is useful, therefore, for secondary teachers to emphasise that such a diagram only represents a model, and is one of several models that together help us understand matter at the atomic scale. Learners’ ideas about the atomic nucleus The term ’nucleus’ itself may sound quite similar to ’neutron’ and this may be a source of confusion. More significantly, students will be familiar with the use of ’nucleus’ in biology and may sometimes - hard as it may seem to appreciate - confuse atoms and cells. In one sense such a comparison is impressive: cells are sometimes considered to be the ’building blocks’ of organisms, and atoms are often said to be the ’building blocks’ of matter. The cell-nucleus-atomic-nucleus analogy can be significant. The cell nucleus is often described as a type of ‘control centre’ for the cell, and the atomic nucleus may be understood to be a control centre for the atom. Making comparisons between different ideas is an important part of developing new concepts, but learners need to be taught to look for the negative as well as the positive aspects of an analogy. An example of this - seeing the atom as like a tiny solar system. Learners’ ideas about atomic structure This lack of application of basic electrical ideas to the atom is reflected in the way students often conceptualise the way the electrons are held in position around the nucleus. According to accepted scientific principles: - All electrons in an atom are attracted to the nucleus. - The force acting on an electron depends upon the magnitude of the nuclear charge and the separation. - The attractive force between an electron and the nucleus acts in both directions: both experience the same magnitude force. - Each electron repels the others with a force which depends upon their separation. To help simplify more complex atoms, we often introduce the idea of ‘shielding’ where inner shell electrons are considered to cancel the effect of an equivalent number of nuclear protons, so we can model the atom as a positive core charge and one shell of outer or valence electrons. This is only partially valid, as the ’electron shells’ are not actually shells and interpenetrate - but it remains a useful approach. However, it is difficult for students to appreciate how the concept of shielding is supposed to work unless they accept the principles above. Interviews with post-16 students studying chemistry revealed the following alternative conceptions: - The nucleus is not attracted by the electrons. - The nucleus attracts an electron more than the electron attracts the nucleus. - The protons in the nucleus attract one electron each. - The electrons repel the nucleus. Learning by analogy - the example of the atom Meaningful learning relies on the learner interpreting new information in the context of what they already know - so that it ’makes sense’ to them. It was suggested that sometimes when students fail to learn the science that is presented to them, this may be due to understanding differently, when they relate the new material to alternative conceptions they already have. When the new ideas are too abstract to be directly related to existing ideas, teachers often call upon comparisons with other more familiar contexts. Atomic structure is clearly a topic which is highly abstract, as students are expected to learn about the internal structure of a conjectured entity which is much too small to be directly experienced. A common comparison that is made is that ’an atom is like a tiny solar system’. The relationship between the nucleus and electrons is here modelled on the sun and planets. The use of this teaching analogy relies upon a number of assumptions; - That an atom is in some ways like a solar system - That the students are familiar enough with the solar system to make use of the comparison - That the students will recognise in which ways the atom is like a solar system, and in which ways it is not. When this was piloted for the project, it was found that students often held alternative ideas about both the atom and the solar system. Some students thought the electrons could not be interacting with each other, as they were interacting with the nucleus, or there was ’no relationship between them’, whilst others acknowledged a gravitational ’reaction’. Some students did know electrons would repel each other, and one suggested ’they repel each other around the nucleus’. Students were asked to list the similarities and differences between the atomic system and the solar system. Some students found it very difficult to suggest more than a couple of similarities or differences (and many did not make the ’obvious’ point about the atom being a good deal smaller than a solar system). The class of 14-1 5 year olds which produced the responses discussed above did have a fair attempt at spotting similarities and differences. Some good suggestions were made for both the similarities, and the differences: - Both the atom and the solar system have centres that attract the surrounding planets or electrons. - Both have forces involved. - They both rotate around a centre point. - More than one thing on the ring in atoms. - Planets have no charge but electrons are negatively charged. - Electrons have virtually no mass and planets have a large mass. - The solar system is a lot bigger. - Different forces. - Planets can be seen with the naked eye, electrons can’t. - The planets rotate around. For the full version of this chapter, see downloads below. - PDF, Size 0.68 mb These PDFs have been taken from the popular book, Chemical Misconceptions : Prevention, diagnosis and care: Theoretical background, Volume 1, by Keith Taber - Currently reading
Sea turtles are one of the Earth’s most ancient creatures BASIC FACTS ABOUT SEA TURTLES Sea turtles are one of the Earth’s most ancient creatures. The seven species that can be found today have been around for 110 million years, since the time of the dinosaurs. The sea turtle’s shell, or “carapace” is streamlined for swimming through the water. Unlike other turtles, sea turtles cannot retract their legs and head into their shells. Their color varies between yellow, greenish and black depending on the species. Hawksbill Sea Turtle, © James Dawson What sea turtles eat depends on the subspecies, but some common items include jellyfish, seaweed, crabs, shrimp, sponges, snails, algae and mollusks. It is difficult to find population numbers for sea turtles because male and juvenile sea turtles do not return to shore once they hatch and reach the ocean, which makes it hard to keep track of them. Did You Know? Green sea turtles can stay under water for as long as five hours even though the length of a feeding dive is usually five minutes or less. Their heart rate slows to conserve oxygen: nine minutes may elapse between heartbeats. Sea turtles are found in all warm and temperate waters throughout the world and migrate hundreds of miles between nesting and feeding grounds. Most sea turtles undergo long migrations, some as far as 1400 miles, between their feeding grounds and the beaches where they nest. Sea turtles spend most of their lives in the water, where not much information can be gathered on their behavior. Most of what is known about sea turtle behavior is obtained by observing hatchlings and females that leave the water to lay eggs. Sea turtles, like salmon, will return to the same nesting grounds at which they were born. When females come to the shore they dig out a nest in the ground with their back flippers, bury their clutch of eggs and return to the ocean. After hatching, the young may take as long as a week to dig themselves out of the nest. They emerge at night, move toward the ocean and remain there, solitary, until it is time to mate. Temperature: Temperatures of the sand where the turtles nest determine the sex of the turtle: below 85 degrees Fahrenheit (30ºC) is predominately male; above 85 degrees Fahrenheit (30ºC) is predominately female. Mating Season: March-October depending on the species. Gestation: 6-10 weeks. Clutch size: Between 70-190 eggs depending on the species. When the young hatch out of their eggs, they make their way to the ocean. Few survive to adulthood. Final Tiles Gallery id=65 does not exist Plan your holiday with Sri Lanka Tourism Hub.
a. Assume that these certain goods are sold in competitive markets. Diagram the market (supply and demand curves) for one of the goods. Show the equilibrium price and quantity. Identify and expain the Consumer's Surplus. Identify and expain the Producer's Surplus. What is true of the general welfare of Americans? b. Assume that Congress enacts a 45% tariff against the good and levies it on the seller's side of the market. Diagram the market (supply and demand curves) for the good. Show the equilibrium price and quantity. Add the tariff to the diagram. Show the new equilibrium price and quantity. What happens to the buyer's price? What happens to the seller's price? Identify and expain the Consumer's Surplus. Identify and expain the Producer's Surplus. What happens to the welfare of Americans as a result of the tariff? Explain the advantages and disadvantages of this tariff. c. Assume that, instead of a tariff, Congress enacts a quota against the good which achieves the same market price and quantity. Diagram the market (supply and demand curves) for a good with the quota. Show the equilibrium price and quantity. Identify and explain the Consumer's Surplus. Identify and explain the Producer's Surplus. What happens to the general welfare of Americans as a result of the quota? Explain the advantages and disadvantages of a quota. d. Assume that the Chinese government is unhappy with both the tariff and the quota because they negatively impact employment in China. What exchange rate policy can the Chinese government adopt to neutralize the negative impact of a tariff on its goods on Chinese employment? How would it effect its policy? 2) On November 5, 2014, Congresswoman Nita Lowey implored the House Republicans to raise the federal minimum wage to $10.10 per hour. In support, she argued, "Raising the minimum wage to $10.10 would take 1.7 million workers off public assistance and reduce government expenditures on current income-support programs by $7.6 billion per year." a. Assume that public assistance is tied to a measure of absolute poverty. What is absolute poverty? Analyze whether Ms. Lowey's statement is correct if poverty is measured absolutely. b. Assume that public assistance is tied to a measure of relative poverty. What is relative poverty? Analyze whether Ms. Lowey's statement is correct if poverty is measured relatively. 3) In an introductory paragraph, explain what a patent is and the rationale for patents. Then, read: Lifting the Patent Barrier to New Drugs and Energy Sources. Identify advantages of patents (in one paragraph) and disadvantages of patents (in another paragraph). In a fourth paragraph, logically deduce whether or not governments should sponsor patents or not. 4) Answer ONE (1) of the following two questions: a. The small upstate town of Geneva, NY, has 10 firms that make watches. The firms' respective output levels are 30 watches per year, 20 watches per year, 10 watches per year, 10 watches per year, 10 watches per year, 10 watches per year, 5 watches per year, and 5 watches per year. Calculate the four-firm concentration ratio for the town's watch-making industry. Calculate the Hirschman-Herfindahl Index (HHI) for the town's watch-making industry. SHOW ALL WORK! Based upon your calculation of the four-firm concentration ratio and the HHI, into which market model would you classify Geneva's watch-making industry? Explain. Based upon your classification of the market structure of the watch-making industry in Geneva, how would you predict that these companies will behave (compete)? What kind of price competition might you observe from these firms? What kind of non-price competition might you observe from these firms? b. The small upstate town of Geneva also has 10 burger shops whose respective shares of the local hamburger market are (as percentages of all hamburgers sold): 20%, 18%, 14%, 9%, 8%, 7%, 6%, 6%, 6%, 6%. What is the four-firm concentration ratio of the hamburger industry in this town? What is the Hirschman-Herfindahl Index (HHI) for the hamburger industry in this town? If the second and third largest hamburger shops merged to form a single firm, what would happen to the four-firm concentration ratio and to the HHI? If you were a prosecutor in the Antitrust Divison of New York State Attorney General's Office, would you ignore or prosecute said merger? Explain. 5) Define and explain each of the performance criteria: allocative efficiency, productive efficiency, x-efficiency, profitability, redistribution of income, and dynamic efficiency. Now, diagram the long-run position of a firm in monopolistic competition and explain how well the firm stacks up against the ideal performance criteria. 6) Diagram and explain why Maria Sharapova, a white Russian tennis player, might earn nearly twice as much in endorsements as Serena Williams, an African-American with a much better win-loss record. What factors other than race might explain the difference in endorsement income? 7) Suppose that you hear two people arguing about energy. One says that we are running out of energy. The other counters that we are running out of cheap energy. Diagram and explain which person is correct and why. In class, Dr. Furfero intimated that neither person might be correct and that not only are we not running our of energy, but we are not running out of cheap energy. Why? By purchasing this solution you'll be able to access the following files:
Influenza, or "flu," is caused by a virus infecting the respiratory system, meaning your nose, throat, bronchial tubes, and lungs. Flu is very contagious and spreads easily from one person to the next. Most people with healthy immune systems will get over the flu within two weeks. However, young children, older adults, and people with chronic illnesses are more likely to develop complications such as pneumonia. Vaccination is your first, and most important, step to reducing your risk of flu and its complications. The Centers for Disease Control and Prevention recommends that people age six months and older get an annual flu vaccine. If the timing aligns, your flu vaccine and COVID-19 booster can be administered during the same visit. Combined flu and COVID-19 appointments are available at certain vaccine centers. Everyday preventive actions can also help reduce the spread of flu. These include washing your hands often, covering coughs and sneezes, avoiding touching your eyes, nose, and mouth and limiting contact when you or others are sick. Flu signs and symptoms usually come on suddenly. People who are sick with flu often feel some or all of these symptoms: - Feeling feverish or chills - Sore throat - Runny or stuffy nose - Muscle or body aches - Fatigue (tiredness) - Vomiting or diarrhea, though this is more common in children than adults. *Please note that not everyone with flu will have a fever. Your doctor may diagnose the flu based on your symptoms, conduct a rapid test or request a laboratory test. Prompt treatment is recommended for people at higher risk of flu complications. This includes young children, adults age 65 and older, pregnant people, and people with certain medical conditions, like asthma, diabetes and heart disease. Learn more about who is high risk (CDC) > When patients are high risk or very sick with the flu, prescription antiviral drugs may be used to lessen symptoms, shorten the time they are sick and reduce the risk for serious complications. Flu Shot Locations There are many convenient ways to get a flu vaccine, including your primary health care provider, your employer, your local health department, or a retail pharmacy in your community. If you are a patient receiving home care, call to ask if they are providing flu vaccines to clients. Vaccine Centers - Flu Shots and COVID-19 Vaccines COVID Vaccine and Testing Center at Union 475 South Street - Morristown
Nonlinear components sometimes need a linear approximation to quickly learn about a circuit’s electrical behavior. The quickest way to approximate a nonlinear component’s electrical behavior is to use a small signal model, which uses a Maclaurin series expansion around a specific operating point. Using a small-signal model helps you understand more about your circuits, but it fails when the input signal gets too large. Too large as compared to? This is discussed later, so a couple of words is all that is needed here. A small-signal model for a diode gives you a quick way to analyze nonlinear circuits. When you’re a physicist or mathematician, you spend plenty of time taking series expansions of different functions. Engineers sometimes need to do the same, but they often don’t know it. One instance where you really need to take a look at series expansions is when you are examining the behavior of nonlinear electrical components and systems. Doing this makes your job of analyzing circuit behavior much easier. The classic nonlinear component most engineers see is a diode. A small-signal model for a diode is extremely easy to understand, and every other small-signal model can be derived using the same mathematical process. To understand what the small-signal diode model means for circuit analysis, we must first understand how it works. The Small-Signal Diode Model Saying a model for an electronic component is a “small-signal” model means something very specific. In particular, we mean that the voltage drop across the component is only a small fraction above or below some desired operating voltage. Developing a small-signal model is all about approximating the voltage drop across the diode and the diode current using a derivative. The goal is to describe how the output (the diode current) changes when there is a small change in the input (the voltage drop). To start, let’s look at the equation for the current in a diode as a function of voltage drop across the diode: Current in a diode as a function of voltage drop across the diode. Please define n, k, and T Here we need to approximate the current as a function of voltage near some operating voltage. First, define V0 as the operating voltage across our diode. The goal of a small-signal model is to get a value for the admittance (or impedance) of the component. The admittance is simply the derivative of the diode current, with respect to the voltage drop evaluated at the operating point: Admittance of the diode at its operating point. It’s important to note that a change in the operating point V0 also changes the admittance. This is to be expected, as the current in a diode is a nonlinear function of the voltage drop. With this in mind, we can approximate the diode current as a linear function of voltage drop across the diode, i.e., as I = VY: Small signal model for the current in a diode as a function of its admittance and voltage drop V near the operating point V0. This equation basically defines Ohm’s law for a diode within a small range of voltages. If, for example, you send an AC signal with small amplitude across the diode, the above equation tells you the relationship between the voltage and current. Simply plug in the function for the AC voltage, and it will give you the current. This enables the use of Kirchoff’s laws to analyze the current in a circuit with a diode near the operating voltage, including circuits with reactive components. Why Use a Small Model? There are two reasons to use a small signal model for circuit analysis in nonlinear circuits: DC current and voltage in a nonlinear component often requires solving a transcendental equation, which often does not have closed-form analytical solutions. When AC voltage is dropped across the nonlinear component, higher-order harmonics are generated due to frequency mixing. Using a small signal model simply ignores the potential for harmonic generation. To see how this is helpful, consider the following circuit: Example circuit with a diode. If you try to calculate the total current in the circuit I1 using series and parallel rules, you’ll find that this current is a function of the voltage drop across the diode. The voltage drop across the diode is then equal to Vd = V - V40 - V20. This gives a complicated transcendental equation for I1 as a function of the current in the remaining components. Using a small-signal model allows the standard Gauss-Jordan matrix technique in SPICE simulations for linear circuits to be used to determine the voltage and current in every component (both for DC and AC inputs). The other reason to use a small-signal model is to avoid the need to consider harmonics generated for AC signals. Mathematically, the current/voltage relationship in a nonlinear component can be approximated using a Taylor or Maclaurin series, which gives a high degree polynomial. For an AC signal, taking powers of the input voltage will produce higher-order harmonics of the AC input. When the AC input is small enough, the generated harmonics will also be small and can be ignored. Otherwise, at large AC input, the current will contain extra harmonics that will be seen in the time domain and frequency domain. More complex methods like harmonic balance analysis are needed to consider the full AC behavior in reactive nonlinear circuits in the frequency domain. The methodology used to describe diodes at a specific operating point can also apply to other components. The same series expansion and operating point technique can be used to approximate linear behavior in: Transistors (note that we’re not referring to load lines) Photodiodes and other electro-optical components Varactors or barium strontium titanate capacitors Power amplifiers operating near saturation Analog mixers, limiters, and multipliers Small-signal models aren’t limited to individual components. Any circuit or N-port network that contains at least one nonlinear component is a nonlinear circuit. Therefore, the overall relationship between inputs and outputs can be described with a small-signal model. In terms of modeling with your circuit design software, you can construct a phenomenological model for a component and include it in a different schematic or circuit. You only need to examine the relationship between each input and output in your nonlinear circuit; what happens within each component is less important.
Here’s How to Get Kids Talking in Math Class! By Mona Iehl We know that whoever is doing the talking is doing the learning, but often teachers scratch their heads trying to get the students to actually talk. We know what works to get those same six students talking and raising their hand each day, but how do we engage every student in truly explaining their thinking and sharing their math reasoning? 1. Consider your types of questions Asking the right questions can make all the difference. Some questions require little student thinking and focus more on achieving the correct answer. A common questioning pattern in our classrooms goes like this: teacher asks a question, student answers, and then the teacher evaluates if the answer is correct or not. This is what research calls the “Initiate-Response-Evaluate IRE pattern.” (Cazden, 1988) This quick process lasts only a few seconds and positions the teacher as the evaluator instead of the facilitator of the discussion. In the NCTM book Principles to Actions, the authors talk about funneling questions that lead students toward a specific idea. Think of the funnel’s wide opening where students enter with various thoughts, approaches, and methods. Then by asking funneling questions, the teacher narrows the students’ understanding to the bottom small opening where there is one right answer. Although this approach to questioning is more open, it does not allow students to make their own connections and sense, but instead the students’ ideas are funneled to the one right answer determined by the teacher. The reality is that teachers use these types of questions often. We want to help our students be successful and achieve. So we support our students in arriving at the right answer. However, I would argue that our job is not to help students get to the answers more easily, but instead help our students to think critically and problem-solve. This mindset shift can help us reframe the types of questions we ask – shifting away from helping students to an answer and toward expressing their thinking and building their reasoning skills. With this shift in our own mindset, we can start to create a classroom that is centered on our students’ thinking and not solely on achieving the answer. 2. Ask open ended questions Open ended questions allow students to explain their thinking. The focus is not on the answer but on sharing what you’re currently thinking, finding patterns in others’ reasoning, supporting your strategy with reasoning, and justifying your answers. With the focus on explaining your thinking, all students are positioned to take the first step to participate without the pressure of being right. Open ended questions invite our students to think, and they encourage students to fully explain themselves. Your questions can be used to help students understand the math task and nudge students toward the key understandings that the task lends itself to. Open ended questions help teachers stay in the facilitator role. If the goal is to get your students talking, then give them the floor. Plan a time in your classroom to allow for more student talk. This could be turn-and-talk’s or a whole group math discussion. Your students’ thinking and their words are leading this discussion. The questions should build on what they are saying in the discussion. For example, if you were hoping the math task would lead to a conversation about addition of fractions using common denominators, but students are sharing and debating about if the fractions are equivalent…then the discussion has to start there and then build to your teaching point. In this case you will want to ask students to further explain and justify their reasoning using evidence from the models about equivalence. Knowing the standards and the math deeply comes into play big here. You have to know the progression of math understanding so that you can help your students through linking what they know and can do with where they need to go next. Getting students talking in math discussions means we have to allow students to explore, tinker, and figure out while talking. Resist the urge to step in and explain or “just show you this one thing.” Instead, listen carefully to what students are saying and ask questions to further understand their thinking. The more you know about what they are thinking the better questions you can ask. The power is in the children’s voices. Let your students explain; let them struggle to explain. Ask the right question and see them work together to develop clarity in their thinking. Remember your math classroom community Laying a solid foundation of community in your math classroom will make true math discussions possible. It is a risk for our students to share what they are thinking. Your community must be welcoming, safe, and supportive. Through students’ relationships, norms and routines, this safety can be achieved. If you want more information on how to build a classroom community, check out my earlier MiddleWeb article, 4 Moves to Help Tweens Overcome Math Anxiety. The less you talk the more they’ll talk As teachers when we make the conscious choice to listen more and talk less, the results are exciting. Students will start to explain their thinking and give us glimmers of their understanding that we can learn from and build upon. Mona Iehl (@HelloMonaMath) is a fifth- and sixth-grade math teacher in Chicago, Illinois. Mona started her career 13 years ago teaching in the primary grades but found her home in the middle grades five years ago. Find her other MiddleWeb posts here. Mona recently took her passion for helping teachers and students find their inner mathematician to a podcast. Listen in at @HonestMathChat.
Although biogas can be used as a fuel, it must firstly be treated to ensure that it is delivered in a useable state. Depending on its source, biogas is a mixture of many elements, some of which are not much use in the generation of fuel and cannot be combusted. Organics provides a wide range of equipment for the treatment of biogas to ensure that, whatever the final destination, it is right for the job. Activated Air Controllers Fuel Delivery Skids Biogas Treatment Equipment Hydrogen Sulphide Bioscrubbers What is Hydrogen Sulphide? Normally biogas contains Hydrogen sulphide (H2S). Hydrogen sulphide is a gas that occurs naturally but can also be produced by human activity. H2S gas is colourless and flammable and can be both poisonous and corrosive but, as H2S is heavier than air, any uncontrolled release will stay low to the ground. In certain situations, H2S can be detected by its smell in concentrations as low as 0.6 parts per billion (ppb). Its toxicity is similar to carbon monoxide and can prevent cellular respiration in organisms. In machinery, its corrosive properties can quickly render equipment inoperative. Monitoring and early detection of H2S could, therefore, mean the difference between life and death or catastrophic breakdown of valuable equipment. Biogas produced by anaerobic digestion is generally rich in H2S. H2s should be treated from biogas. How is H2S produced? Landfill sites can produce H2S in the presence of wastes plasterboard or other products that contain sulphur. It can also be present if there is the presence of gypsum (CaSo4.2H20). In anaerobic digestion, H2S is produced by the microbial breakdown of organic material under anaerobic conditions and produces biogas that must be treated before using in vulnerable machinery. What is the environmental impact of H2S? In humans, prolonged exposure to high enough levels of H2S can cause unconsciousness and those affected may continue to experience headaches, reduced attention span and altered motor functions. Effects of H2S gas exposure may not become apparent for up to 72 hours following removal from the affected environment. As H2S is heavier than air it usually accumulates in low lying areas of poorly ventilated spaces. During the production and collection of biogas in landfill sites or anaerobic digestion plant, H2S gas in the presence of air and moisture can form sulphuric acid which is capable of corroding metals within machinery that is often not seen. How can H2S be treated? There are several types of treatment system that involve high initial investment together with high ongoing costs of operation. Organics has developed bio-scrubber technology, the main advantage of which is that, in most circumstances, no additional costs for chemical-additions are incurred. The bacteria involved in the process are ubiquitous and, as long as correct environmental conditions are maintained, the bacteria will function reliably and predictably in the removal of hydrogen sulphide from gas streams. The system is ideal for use with biogas producing projects that rely on anaerobic digestion such as bespoke AD projects or biogas generated in landfill sites. What is a gas chiller used for? Gas chillers are used to reduces the moisture content of process gas streams. As well as reducing moisture, chillers will also reduce the concentration of chemical compounds such as ammonia and Volatile Organic Compounds (VOCs). The process of extraction of landfill gas, or the recovery of biogas from anaerobic digestion, for power generation, results in the formation of condensate that can contain a wide range of potentially corrosive elements. If these elements are not removed from the gas flow, they can drop out of the condensate in the engine manifold or charge-cooler; a phenomenon that will eventually result in catastrophic engine failure. To avoid this happening, installation of a chiller unit will remove condensate prior to entry of the gas to the engine. How does a chiller function? A gas chiller can reduce the temperature of a biogas stream to around 2ºC. Temperatures below this can also be achieved but will result in freezing of the heat exchanger tubes. Where temperatures of less than zero are required it will be necessary to run tandem heat exchangers, switching the flow from one to the other as they become blocked with ice. By reducing the temperature to close to freezing point the relative humidity of the gas can also be reduced, thus minimising the possibility of condensate formation in pipes down-stream of the chiller. The unit is usually placed before or after the booster unit on biogas collection systems either on landfill gas or bespoke anaerobic digesters. Chiller packages are, as with other items of purpose built process plant supplied by Organics, unlimited in practical size. Flow rates of up to 10,000 Normal cubic metres per hour can be effectively “chilled” to the target levels. It is often the case that suppliers of certain types of equipment, such as internal combustion engines and gas turbines, will specify a maximum moisture content in the gas to be fed to their plant. The options for dealing with such requirements are limited. Hydroscopic filters will reduce dew points by up to 6ºC but this may provide inadequate protection, especially as the dew point of the feed gas often varies significantly. Where properly designed and built a packaged chiller will reliably ensure the target dew point is continuously met and the equipment is most effective on landfill biogas or biogas generated within AD plants. Activated Air Odour Control Units What is an Activated Air Unit? The treatment and storage of waste material can often result in strong odours being generated that, if not treated, can cause problems for neighbours and workers on the site. Deodorisation with an Activated Air unit is based upon high-speed oxidation. Molecules oxidised by this method cannot be detected by the human nose. An Activated Air unit consists of a stainless steel cabinet containing wide-mesh UV-catalysts. Ambient air is passed through the unit, from atmosphere without any pre-treatment, and radiated. How does it work? By means of a high-voltage applied to an ultra-violet light generating, catalytic wire mesh, molecules in ambient air are split and energised, converting the moisture and air into a flow consisting of a mixture of unstable atoms, ions and radicals, with elevated electron activity levels. These Activated Air molecules may then be injected into a gas carrying target compounds. The result is the high-rate oxidation of odorous molecules. - Highly efficient Odour Control by means of the high-rate oxidation of target substances, - No moving parts, mechanical wear, - No chemical additions required, - No water consumption and no waste products - Low energy requirements Gas Delivery Fuel Skids Fuel-skids for power generation The absolute requirement for a fuel skid for power generation is long-term reliability Units designed, manufactured and supplied by Organics employ technology that has been tried and tested for pumping applications for landfill gas and biogas from AD where unnecessary downtime has immediate ramifications in terms of revenue generation and must be avoided. Gas-pumping units manufactured and supplied by Organics have a well-established record in providing landfill gas to generators with up times in excess of 99%. Biogas is a unique fuel It is now well acknowledged that landfill biogas or biogas from AD plants can be employed as a unique fuel that does not normally require back-up from deisel or natural gas injection. However, biogas possesses characteristics that are not matched by any other similar fuel gas, such as natural gas. For this reason, a biogas fuel skid must be built specifically for this application. Of particular note are the high-levels of moisture drop out and the possibility of a wide range of potentially corrosive trace gases. These range from halogens to ammonia and mercaptans. - High-reliability gas pumping sets - Optional air blast cooling and refrigerated chilling for dew-point management - Automatic moisture removal systems for collected condensate - Integrated control systems with facilities to link into main control centre. - Flow rates available: 50 to 20,000 cubic metres per hour - Suction pressure head rarely needs to exceed 150 mbar. Deep-vacuum systems can also be considered for particular situations. - Delivery pressure head: 300 to 600 mbar g are normally achieved with twin-stage centrifugal blowers. Higher pressure heads may be achieved with screw compressors, rotary vane compressors and multi-stage reciprocating compressors. - Organics fuel skids have a well-established record in providing biogas to generators with up times in excess of 99%.
In 1880, Jaques and Pierre Curie discovered the piezoelectric properties that would later be used in quartz movements. More than four decades later, in 1921, Walter G. Cady built the first crystal oscillator. An oscillator is a circuit that uses mechanical resonance of a vibrating crystal of piezoelectric material to create an electric signal with constant frequency. Without the discovery of piezoelectric and the invention of the crystal oscillator, we would not have the timepieces we have today. The world's first quartz movement was invented in 1927 by Warren Marrison and J.W. Horton.
No registration needed for instructor resources for younger students will find it all your experiment could have a worksheet for some worksheets are happy with a place variables? The appropriate space Hop psikologjia sociale edmond dragoti pdf. After scientists complete an experiment they report their conclusions. Once you have come up with your hypothesis make sure you write it down. If all great opportunity for? Much more than documents. Grade Scientific Method Worksheet Answers. Clinical Procedure For Young children. Scientific Method Review Identifying Variables Worksheet To rent a. World Journal of Education, vol. The Biochemical Guessing Game! Students understand how work on their stuff on facebook at any time intervals or base assumptions on. What is the information gathered by observation or experimentation when it is not called evidence? They have to choose one that is can be tested safely and in a short amount of time. Get practice scientific skills methods in The skills they can be good experiment. Perhaps with this quick stem toys, scientific method over again in. Life teachers to download from a secure site for Instructor Resources. Is the Egg Raw or Cooked? IB Text Book ib_sl_textbook ib. This document with every research method trivia quizzes, it also important because it meets with. Students need to be equipped with the ability to care, be responsive, critical, and creative to solve these problems. This study uses several instruments that is study sheet, validation sheet, response questionnaire sheet, scientific literacy test sheet and supported by student activity observation sheets. Once a hypothesis or classwork to scientific skills methods - Residency This skill is a successful scientific. Aetna Formulary She then sealed the plants in plastic bags. If html does not have either class, do not show lazy loaded images. This starts much of the process of the scientific method over again. Can Crickets Tell the Temperature? CONSUME END KEY case template. For their solutions for students after using when they often it? - Veterans Affairs Worksheets that save paper, ink and time. Ms Dangda was my supervisor when I worked at Bumrungrad Hospital. This is a great way to turn a science activity into an experiment. Ministry of Education and Culture. COPY in order to edit these files. Put the step number next to each step of the scientific method for this problem. WordInvalid character in name. Source Chemotherapy The Book CONSUME HOME KEY case template. - Ball Valves The most relevant to appraise what your. Oreo cookies on the STEAM MINIS page! Water chemists study the impact of water on other elements in these. How can _you_ follow up on your own observations of the natural world? Describes a record what do. For instance, in this case, we would plug the toaster into a different outlet and see if it toasts. It is a hypothesis make teaching resources were some form literary or both scientific skills and. This worksheet in recreation by observing, worksheets below too small values. Need to scientific skills worksheet answers Scientific method worksheet answers is. Meanings and definitions of words with pronunciations and translations. What steps and scientific skills methods are scientists of student. The weather will be cold. How Flocabulary works with Clever. You ask questions you will sink because this worksheet high school worksheets focus they often for? Finally we use many kids here are more time is an ice science! Students learn the definitions for question, hypothesis, experiment, data, and conclusion, then use them to label a science report.
The discovery was uncovered by researchers from the Siberian Section of the Russian Academy of Sciences (H) while conducting radiocarbon analyses on fragments of reindeer antler found at the Kushevat Paleolithic site in the Lower Ob region. In addition to the antler bones, a woolly mammoth (Mammuthus primigenius), a steppe bison (Bison Priscus), an Paleolithic Age elk (Alces alces), a deer (Cervus elephus sibiricus), and maybe a musk ox were also examined (Ovibos moschatus). The bones were inspected, and their age was determined using a series of 20 different radiocarbon dates that all fell between 20 and 40 thousand years ago. Even while the finding only shows that animals, not humans, inhabited the Arctic region 40,000 years ago, it has now been utilized as the basis for further study that dates human activity in the Ob area to that time. This is because recent examination of two reindeer antlers revealed evidence of human involvement within this group of bones. The idea that an ancestor of modern man, Homo sapiens sapiens, may have invaded the Arctic and Subarctic has long intrigued scientists. It is commonly assumed that Paleolithic man traveled via the Ob River Valley. It is estimated that between 50,000 and 60,000 years ago, modern man first appeared in Europe and Asia. It is still unknown where the modern man formerly resided and how he crossed the Urals. It was long thought that between 12,000 and 30,000 years ago, a large glacier covered the northern part of Western Siberia (just like the north of America and Europe). To the south of the glacier was a dammed basin, 130 meters deep. “An worldwide scientific effort that combined AMS dating and optical-stimulating luminescence proved that there was no ice cover in the north of Western Siberia 12,000-30,000 years ago thanks to colleagues from Europe and Russia. The older historical period was north of Salekhard, 90 000-60,000 years ago. The Ob valley’s ice-dammed basin wasn’t much higher than 60 meters. This paleogeographic representation is entirely distinct. I thought for thirty years that an ancient human may have lived in the northern part of Western Siberia under the correct conditions. The project manager and director of the laboratory at the Institute of Geology and Mineralogy named after V.I. V.S. suggested that now that we had the opportunity, we might attempt to prove it by discovering Homo sapiens artifacts from 30,000 to 50,000 years ago in the north of the Ob. According to the Barents Observer, the research “suggests that Homo sapiens and not merely Neanderthals inhabited the Arctic Circle in the Upper Paleolithic age.” Prior to around 20 years ago, the only known past inhabitants of the region were Neanderthals, not Homo sapiens. This was discovered by determining the age of a collection of bones discovered in 2001 at the Yakutia site using radiocarbon dating. The Neanderthals arrived in the region between 28,500 and 27,000 years ago, according to the radiocarbon findings. Two important developments have come about as a consequence of the latest AMS investigation. The first is that Homo sapiens first emerged in the area north of the Arctic Circle 40,000 years ago, and the second is that both Neanderthals and Homo sapiens resided in the Arctic Circle during the Paleolithic Age.
You can tell a lot about a country from its lights. New research suggests that NASA’s Defense Meteorological Satellite Program Operational Linescan System — a series of satellites that have been taking pictures of nighttime lights on Earth’s surface for nearly 20 years — can reveal details about changes happening on the ground. “We can now ask how does observed lighting behave in response to things such as population and economic growth, external investments, war, and economic collapse,” said Christopher Elvidge, who leads the National Geophysical Data Center’s Earth Observatory Group, during a presentation at the 2011 American Geophysical Union meeting on Dec. 7. For instance, the satellites saw a steep decline in lighting in Rwanda in 1994 and the following years, reflecting that country’s civil conflict and genocide. Similarly, a civil war in Cote d’Ivoire from 2002 to 2004 severely darkened the country, with lights only returning in recent years. As well, increased lighting in Iraq in 1999 corresponded to the UN lifting import restrictions at the time, while external investment in Afghanistan led to increases in satellite-observed lighting starting in 2002. Perhaps not surprisingly, countries undergoing rapid growth, such as China, had a high correlation between lighting and both GDP and population. In contrast, highly developed countries, such as the U.S. and Western Europe, showed fairly stable lighting patterns that didn’t shift despite increases in population and GDP. The researchers also observed that countries showing little relationship between lighting and either population or GDP — including those in Eastern Europe and Africa — often had some sort of internal instability, which often affected their electric power systems. Below you can see a video showing India’s lighting changes over the last 20 years.
I could introduce you to this weeks topic by telling you it’s about the Inverse-square law, and I could continue with the definition like this: The Inverse-square law is any physical law stating that some physical quantity is inversely proportional to the blah, blah, blah, blah! Yeah, Google it if you want the definition, because I just want to give you the nuts and bolts. Along with figuring out lots of things like astronomical distances, radiation, and acoustics, this law is used to explain the “falling off” of light over distance. Here we go: Imagine you have a light source (flash, lamp, etc.) positioned 1 meter away from your subject. You decide to move that light source to 2 meters away from your subject. How much of the light’s power will hit your subject. 1/2? nope, only 1/4 of the original power. Basically, the rule is every time the distance is doubled, the intensity is reduced to a quarter of the power. As we learned from above when moved from 1 to 2 meters, we have only 1/4 of the light. If that light is moved to 4 meters it’s now 1/16 of the original power or 1/4 of the previous intensity. The equation is simple, take the distance, square that number and then put a one above it turning it into a fraction. Light naturally travels in a ever widening pattern. For example, the light from your camera flash will travel in a V-shaped or pyramidal pattern, refer to the picture below. The light photons do not become weaker, the beams actually distribute over a wider area. Maybe you could look at it as diluting the light. So, why is this important for photography? First, let me give you this tidbit of info. When the light shines in a particular direction, the change in intensity drops very quickly in the first few measurements of distance, then the “fall-off” slows down as the distance increases. Here’s an example. Let’s say at 1 meter, you have 100% of the light power hitting your subject. When that distance doubles to 2 meters, the light is now 25%, at 3 meters it’s 11%, at 4 meters it’s 6%; but now at 5 meters the power is 4% and every meter after that, you only see a percentage drop of roughly 1%. This is important for exposure for a couple of reasons, if you have a subject that is very close to the light source and they’re modeling various poses, chances are they will change their distance from the light. Being so close to the light and changing their distance even by one step can create a huge change in exposure. Now, you take that same model and place them, say 7 meters from the light, they now have plenty of play, front and back with very little change in exposure. Using this method, you won’t have to check for exposure and change your aperture every time your model moves. You might say, that only takes a few seconds, but those bits of seconds start to add up fast on a shoot. Time is money. Also, this applies with group photos too, if they’re close to the light and one person is behind another, then obviously someone is out of exposure. Moving the group away to that “roomy” exposure area is your answer. In the post production realm, you are also spending less time with fixes and more time with effects. I hate the “fix it in post” attitude, it wastes your time and costs your client more money. That’s it for today, join me every Techie Tuesday, please feel free to leave a comment or question.
This chapter turns to World War II in Europe. It first focuses on the sources of German expansion, which arose from the belief, grounded in Nazi ideology, that Germany faced irreversible decline absent the acquisition of most of Eastern Europe. By the late 1930s, Germany's rearmament and Stalin's purge of the Red Army officer corps created a situation in which Germany would never have a better opportunity to address Hitler's fears. Consistent with the commitment problem argument, Hitler had expansive war aims that he pursued through risky strategies and refused to abandon even in the face of military defeats. The chapter then analyzes the Allied refusal to negotiate with Germany, highlighting the British decision not to negotiate after the fall of France and the Allied decision to demand Germany's unconditional surrender. Keywords: World War II; Europe; German expansion; Nazi ideology; Eastern Europe; Red Army; France; surrender Chapter. 15972 words. Subjects: International Relations Full text: subscription required
Summary: The Barn owl, was once feared as an omen of death. Now that we understand the Screech owl's positive environmental impact, we welcome this bird of prey. The Barn owl is the most widely disbursed species of owl. It can be found in many different areas in the world except for deserts, Polar Regions, northern Asia, Indonesia, and the Pacific Islands. In the United States the Barn owl, also known as the Barn owl, is so called because of its distinct screech call that can be heard for some distance. It also hisses when captured or is threaten by an intruder. But, along with its œbark, this owl also possesses a bite. It will gladly use its sharp talons if you choose to ignore its verbal warnings. The Barn owl is a pale, long-winged, long-legged owl with a short square tail. It has a peculiar heart-shaped face disc with sharp black eyes and feathers above the beak, making it look like it has a nose. Its coloring is a mixture of buff and grey, with brown markings on its back and wings. The wings also have bands of darker brown or black. As with other birds of prey, the female is larger than the male. Chicks are covered with fluffy down feathers, but have the distinct face disc early on. When the chicks fledge the fluffy down feathers will be replaced with adult feathers, including flight feathers. As with most owls, Barn owls are nocturnal hunters, but can also be found hunting shortly before dusk and shortly after dawn. The bird prefers open farmland or grassland with some interspersed woodland cover and it likes to hunt along the edges of the woods. Broken farmland also provides a variety of barns and other farm out buildings that can be used for sheltered roosting and nesting sites. The owl's flight is silent because of tiny serrations at the leading edge of their flight feathers. These serrations helps break up noise producing turbulence. The owls hunt by flying low and slow over open fields and hover over spots that conceal potential prey. They have also been observed using fence posts or other lookouts to ambush prey. Because the majority of the owl's diet is rodents, which can damage a farmer's crops, farmers will often provide nesting/roosting boxes for the owls. Farmers consider these owls as the most economically valuable wildlife animals and try to encourage them to remain in their area. The owls have very acute hearing and easily hear prey moving under snow. They will pounce on the prey driving their talons under the snow to grasp the prey. Small prey is eaten whole, while larger prey is torn into chunks. Later any undigested fur, feathers, and bones, are regurgitated in what is called a œpellet. Scientists often use owl pellets to study the ecology of a current or past habitat. The owls do have predators which include opossum, raccoons, larger raptors such as hawks, eagles, and other owls. However, the biggest threat is humans and their pets, particularly cats, both domesticated and feral. Humans have in the past considered owls as demons and harbingers of death. Now, that we have passed (mostly) from the dark ages and have been enlightened by all the Harry Potter movies, we know that owls are beneficial and welcomed guests to our property.
Read this article to learn about the need of value based environmental education! Environmental education or environmental literacy is something that every person should be well versed with. The principles of ecology and fundamentals of environment can really help create a sense of earth-citizenship and a sense of duty to care for the earth and its resources and to manage them in a sustainable way so that our children and grand children to inherit a safe and clean planet to live on. i. Human values: Preparation of textbooks and resource materials about environmental education can play an important role in building positive attitudes about environment. The basic human value ‘man in nature’ rather than ‘nature for man’ needs to be infused through the same. ii. Social values: Love, compassion, tolerance and justice which are the basic teachings of most of our religions need to be woven into environmental education. These are the values to be nurtured so that all forms of life and the biodiversity on this earth are protected. iii. Cultural and religious values: These are the values enshrined in Vedas like “Dehi me dadami te” i.e. “you give me and I give you” (Yajurveda) emphasize that man should not exploit nature without nurturing her. Our cultural customs and rituals in many ways teach us to perform such functions as would protect and nurture nature and respect every aspect of nature, treating them as sacred, be it rivers, earth, mountains or forests. iv. Ethical values: Environmental education should encompass the ethical values of earth- centric rather than human-centric world-view. The educational system should promote the earth-citizenship thinking. Instead of considering human being as supreme we have to think of the welfare of the earth. v. Global values: The concept that the human civilization is a part of the planet as a whole and similarly nature and various natural phenomena over the earth are interconnected and inter-linked with special bonds of harmony. If we disturb this harmony anywhere there will be an ecological imbalance leading to catastrophic results. vi. Spiritual values: Principles of self-restraint, self-discipline, contentment, reduction of wants, freedom from greed and austerity are some of the finest elements intricately woven into the traditional and religious fabric of our country. All these values promote conservationism and transform our consumerist approach. The above-mentioned human values, socio-cultural, ethical, spiritual and global values incorporated into environmental education can go a long way in attaining the goals of sustainable development and environmental conservation. Value-based environmental education can bring in a total transformation of our mind-set, our attitudes and our lifestyles. Approaches to impart environmental education. Environmental education needs to be imparted through formal and informal ways to all sections of the society. Everyone needs to understand it because ‘environment belongs to all’ and ‘every individual matters’ when it comes to conservation and protection of environment.’ Various stages and methods that can be useful for raising environmental awareness in different sections of the society are as follows: (i) Among students through formal education: Environmental education must be imparted to the students right from the childhood stage. It is a welcome step that now all over the country we are introducing environmental studies as a subject at all stages including school and college level, following the directives of the Supreme Court. (ii) Among the masses through mass-media: Media can play an important role to educate the masses on environmental issues through articles, environmental rallies, plantation campaigns, street plays, real eco-disaster stories and success stories of conservation efforts (iii) Among the planners, decision-makers and leaders: Since this elite section of the society plays the most important role in shaping the future of the society, it is very important to give them the necessary orientation and training through specially organized workshops and training programmes. Publication of environment-related resource material in the form of pamphlets or booklets published by Ministry of Environment & Forests can also help in keeping this section abreast of the latest developments in the field.
- As you commute to work or school in the morning, which is most likely to be larger? - A. The magnitude of your displacement - B. The distance you travel - C. Not enough information to say - If you are carrying a ball and running at constant speed and wish to throw the ball so that you can catch it as it comes back down, should you - A. throw the ball at an angle of about 45o above the horizontal and maintain the same speed? - B. throw the ball straight in the air and slow down to catch it? - C. throw the ball straight in the air and maintain the same speed? - As a projectile moves in its parabolic path, the velocity and acceleration vectors are perpendicular to each other - A. everywhere along its path - B. at the peak of its path - C. nowhere along its path - D. not enough information is given - A home run is hit in a baseball game. The ball is hit from home plate into the center field stands, along a parabolic path. What is the acceleration of the ball - while it is rising? - at the higher point of the trajectory? - while it is descending after reaching the highest point? (IGNORE AIR RESISTANCE) Answers: b, c, b, g = 9.80 m/s2 for all situations,or 9.80 m/s2,or -9.80 m/s2
The mad dash for riches that would later become known as the California Gold Rush began innocently enough. On the morning of January 24, 1848, James W. Marshall discovered bright specks of gold running through the channel of water that passed under the sawmill where he worked – Sutter’s Mill. Word spread quickly of the discovery of gold – and opportunists flocked to the area to pan for gold. By late 1848 into early 1849, hordes of men (and women) were flocking to California. The adventurers became known as “49ers,” named after the year in which many of them arrived. While many gold seekers made a profit, especially the earlier to arrive, few became wealthy, and many were left poorer than before they made the trip. The biggest effect of the California Gold Rush was on California itself. In 1846, San Francisco was a small town of about 200 settlers. By 1852 – just six years later – the population had swelled to 36,000. By 1870, the population had reached 150,000. Photo courtesy of OSUCommons When Abbey Road, one of the Beatles’ most famous albums, was released in September of 1969, the last track listed on the second side of the record was “The End”. However, fans soon discovered that if they left their records playing after the conclusion of that song, they would hear 14 seconds of silence, and then a 23 second song titled, “Her Majesty.” This is considered to be the first “hidden track” in the history of popular music. In most cases, a hidden track is included on a record to be an inside joke or special surprise to fans. But in the case of “Her Majesty,” its inclusion was a complete accident. The song was originally intended to appear in the middle of the second side, but it was removed, and Paul McCartney asked for it to be destroyed. However, EMI Music had a strict policy of saving everything the Beatles recorded, so it was instead placed at the end of the tape, separated from the rest of the recordings by a liberal amount of silence. When the tape was transferred to vinyl record, “Her Majesty” was unintentionally included in the album. Pierre de Fermat is widely held as one the most influential mathematicians in Western history. He lived from 1601 to 1665, and though he made a number of contributions to the study of mathematics, he is perhaps bet known for the problem that became known as Fermat’s Last Theorem. In 1637, in the margins of one of his books, Fermat wrote that he has proven that no three positive integers can satisfy the formula an + bn = cn, if n is greater than two. Unfortunately he wrote, “I have discovered a truly marvelous proof of this, which this margin is too narrow to contain.” This proof could never be found in his papers, and no other mathematician could prove that this statement was true for all positive integers. This problem was the subject of much speculation, and large cash prizes were offered throughout the 19th and 20th century to anyone who could supply a valid proof. However, it wasn’t until 1994, 329 years after Fermat’s death, that the theorem was finally successfully proven, by British-born mathematician Andrew Wiles. Three years later, Wiles collected $50,000 from the German Göttingen Academy of Sciences, a prize that was initially established in 1908 and went unclaimed for 89 years. Many of us think of Santa Claus as a timeless figure, but in fact the image we have of him is a relatively modern one. Much of what makes Santa look like, well, Santa, stem from this illustration by cartoonist Thomas Nast, which appeared in the January 1, 1881 issue of Harper’s Weekly. The platypus, native to the eastern coast of Australia, is by all account one of the stranger creatures on Earth. As a monotreme, it has many of the characteristics of other mammals, but different from other mammals in some important ways (for example, platypuses lays eggs). Here are four more things you may not have known about this creature. - Platypuses are venomous. The male playtpus has spurs on its back legs that release a fairly powerful vemon. While it won’t kill a human, it would cause severe pain. - Platypuses use electrolocation. The playpus contracts special muscles along its body to emit an electrical field which they can then “read’ with receptors located on their bill. This is the only sense they use when hunting for food (they eat shrimp, crayfish, worms, and other small creatures). - Platypuses have a lower body temperature than most other mammals, averaging only 90° F. - Platypuses can sleep for up to 14 hours per day.
transform into budding scientists. experiment, experience & invent. Visitors are transformed into budding scientists in the invent exhibit area. Through experimentation & interactive’s in this gallery encourage the exploration of various physical sciences including air, gravity, magnetism, force, velocity and circuits to name a few. This exhibit area introduces physical science and process of experimentation to children using exciting cause and effect interactives. At the entrance of this gallery a life size giant Pin screen containing more than 90,000 movable pins greets the visitors. Make a first impression over and over again. Whether pushing on the pins to leave your hand prints or to write “wow” the tactile feel of a pin screen appeals to children and adult alike and induces the fine sense of touch in young children. The Bernoulli table and Air test column not only make the power of air visible but also encourage children to understand air along with its properties. The Air wall captures the imagination and beckons children to experience the intrigue, sound and movement of air. Move different objects with powerful air gushing through transparent tubes. Observe which object move faster and higher. The Scarf fountains are a wonderful contraption of connected tubes where children feed scarves in a rainbow of colors into the transparent air powered structure. The colorful scarves shoot up through the pipes at high speeds to heights of 20 feet and more and are released in a burst of energy from high above. In contrast they gently float down slowly to land on or be caught by the children. The Air propulsion unit teaches about the principles of flight. Learn how pressurized air launches objects with tremendous force. Bring out the engineer in you and Invent your own car using lego blocks. Race with your friends. The timers on our invent a car racetrack are accurate to the second. Want to make it go faster? Go back to the work table to make changes and then race it again to see if it worked. Learn different styles of making paper airplanes in Invent a plane airplanes that fly far and fast, ones that do flips and ones that glide. Children understand about flight, aerodynamics and science form models made form folds in a paper. Magnetism introduces magnets to children and helps them investigate forces of attraction and repulsion, magnetic and nonmagnetic surfaces, and push and pull. Create 3D models with Magna tiles and comprehend the forces of magnets. What goes up must come down. Gravity is a basic force in the universe. Explore and test it at our Gravity ball drop. What is an electrical circuit? How does a circuit work? How can you connect a power source to make something work? Find answers while exploring our Circuit board.
Nuclear fission is a complex process that involves the rearrangement of hundreds of nucleons in a single nucleus to produce two separate nuclei. A complete theoretical understanding of this reaction would require a detailed knowledge of the forces involved in the motion of each of the nucleons through the process. Since such knowledge is still not available, it is necessary to construct simplified models of the actual system to simulate its behaviour and gain as accurate a description as possible of the steps in the process. The successes and failures of the models in accounting for the various observations of the fission process can provide new insights into the fundamental physics governing the behaviour of real nuclei, particularly at the large nuclear deformations encountered in a nucleus undergoing fission. The framework for understanding nuclear reactions is analogous to that for chemical reactions and involves the concept of a potential-energy surface on which the reaction occurs. The driving force for physical or chemical reactions is the tendency to lower the potential energy and increase the stability of the system. Thus, for example, a stone at the top of a hill will roll down the hill, converting its potential energy at the top to kinetic energy of motion, and will come to rest at the bottom in a more stable state of lower potential energy. The potential energy is calculated as a function of various parameters of the system being studied. In the case of fission, the potential energy may be calculated as a function of the shape of the system as it proceeds over the barrier to the scission point, and the path of lowest potential energy may be determined. As has been pointed out, an exact calculation of the nuclear potential energy is not yet possible, and it is to approximate this calculation that various models have been constructed to simulate the real system. Some of the models were developed to address aspects of nuclear structure and spectroscopy as well as features of nuclear reactions, and they also have been employed in attempts to understand the complexity of nuclear fission. The models are based on different assumptions and approximations of the nature of the nuclear forces and the dynamics of the path to scission. No one model can account for all of the extensive phenomenology of fission, but each addresses different aspects of the process and provides a foundation for further development toward a complete theory. Nuclear models and nuclear fission The nucleus exhibits some properties that reflect the collective motion of all its constituent nucleons as a unit, as well as other properties that are dependent on the motion and state of the individual nucleons. The analogy of the nucleus to a drop of an incompressible liquid was first suggested by George Gamow in 1935 and later adapted to a description of nuclear reactions (by Niels Bohr ; and Bohr and Fritz Kalckar ) and to fission (Bohr and John A. Wheeler ; and Yakov Frenkel ). Bohr proposed the so-called compound nucleus description of nuclear reactions, in which the excitation energy of the system formed by the absorption of a neutron or photon, for example, is distributed among a large number of degrees of freedom of the system. This excited state persists for a long time relative to the periods of motion of nucleons across the nucleus and then decays by emission of radiation, the evaporation of neutrons or other particles, or by fission. The liquid-drop model of the nucleus accounts quite well for the general collective behaviour of nuclei and provides an understanding of the fission process on the basis of the competition between the cohesive nuclear force and the disruptive Coulomb repulsion between protons. It predicts, however, a symmetric division of mass in fission, whereas an asymmetric mass division is observed. Moreover, it does not provide an accurate description of fission barrier systematics or of the ground-state masses of nuclei. The liquid-drop model is particularly useful in describing the behaviour of highly excited nuclei, but it does not provide an accurate description for nuclei in their ground or low-lying excited states. Many versions of the liquid-drop model employing improved sets of parameters have been developed. However, investigators have found that mass asymmetry and certain other features in fission cannot be adequately described on the basis of the collective behaviour posited by such models alone. A preference for the formation of unequal masses (i.e., an asymmetric division) was observed early in fission research, and it has remained the most puzzling feature of the process to account for. Investigators have invoked various models other than that of the liquid drop in an attempt to address this question. Dealing with the mutual interaction of all the nucleons in a nucleus has been simplified by treating it as if it were equivalent to the interaction of one particle with an average spherical static potential field that is generated by all the other nucleons. The methods of quantum mechanics provide the solution for the motion of a nucleon in such a potential. A characteristic set of energy levels for neutrons and protons is obtained, and, analogous to the set of levels of the electrons in an atom, the levels group themselves into shells at certain so-called magic numbers of nucleons. (For both neutrons and protons, these numbers are 2, 8, 20, 28, 50, 82, and 126.) Shell closures at these nuclear numbers are marked by especially strong binding, or extra stability. This constitutes the essence of the spherical-shell model (sometimes called the independent-particle, or single-particle, model), as developed by Maria Goeppert Mayer and J. Hans D. Jensen and their colleagues (1949). It accounts well for ground-state masses and spins and for the existence of isomeric nuclear states (excited states having measurable half-lives) that occur when nuclear levels of widely differing spins lie relatively close to each other. The agreement with observations is excellent for spherical nuclei with nucleon numbers near the magic shell numbers. The spherical-shell model, however, does not agree well with the properties of nuclei that have other nucleon numbers—e.g., the nuclei of the lanthanide and actinide elements, with nucleon numbers between the magic numbers. In the lanthanide and actinide nuclei, the ground state is not spherical but rather deformed into a prolate spheroidal shape—that of a football or watermelon. For such nuclei, the allowed states of motion of a nucleon must be calculated in a potential having a symmetry corresponding to a spheroid rather than a sphere. This was first done by Aage Bohr, Ben R. Mottelson, and Sven G. Nilsson in 1955, and the level structure was calculated as a function of the deformation of the nucleus. A spheroid has three axes of symmetry, and it can rotate in space as a unit about any one of them. The rotation can occur independent of the internal state of excitation of the individual nucleons. Various modes of vibration of the spheroid also may take place. Since this deformed shell model has components of both the independent-particle motion and the collective motion of the nucleus as a whole (i.e., rotations and vibrations), it is sometimes referred to as the unified model. In Aage Bohr’s application of the unified model to the fission process, the sequence of potential-energy surfaces for the excited states of the system are considered to be functions of a deformation parameter (i.e., elongation) characterizing the motion toward fission and evaluated at the saddle point. As the system passes over the saddle point, most of its excitation energy is used up in deforming the nucleus, and the system remains “cold”; i.e., it manifests little excitation, or heat, energy. Thus, only the low-lying excited states are available to the system. The spin and parity of the particular state (or channel) in which the system exists as it passes over the saddle point are then expected to determine the fission properties. In this channel (or transition-state) analysis of fission, a number of characteristics of the process are qualitatively accounted for. Hence, fission thresholds would depend on the spin and parity of the compound nuclear state, the fission fragment angular distribution would be governed by the collective rotational angular momentum of the state, and asymmetry in the mass distribution would result from passage over the barrier in a state of negative parity (which does not possess reflection symmetry). This model gives a good qualitative interpretation of many fission phenomena, but it must assume that at least some of the properties of the transition state at the saddle point are not altered by dynamical considerations in the descent of the system to the scission point. It is the only model that provides a satisfactory interpretation of the angular distributions of fission fragments, and it has attractive features that must be included in any complete theory of fission. The first application of the spherical-shell model to fission was the recognition that the positions of the peaks in the fission mass distribution correlated fairly well with the magic numbers and suggested a qualitative interpretation of the asymmetric mass division. Thus, a preference for the formation of nuclei with neutron numbers close to 82 would favour the formation of nuclides near the peak in the heavy group and would thus determine the mass split for the fissioning system (see Figure 4). Some extra stability for nuclear configurations of 50 protons would also be expected, but this is not particularly evident. In fact, the so-called doubly magic nucleus tin-132, with 50 protons and 82 neutrons, has a rather low yield in low-energy fission. A more quantitative application of the spherical-shell model to fission was undertaken by Peter Fong in the United States in 1956. He related the probability of formation of a given pair of fragments to the available density of states for that pair of fragments at the scission point in a statistical-model approach. A model of this sort predicts that the system, in its random motions, will experience all possible configurations and so will have a greater probability of being in the region where the greatest number of such configurations (or states) is concentrated. The model assumes that the potential energy at the saddle point is essentially all converted to excitation energy and that a statistical equilibrium among all possible states is established at the scission point. The extra binding energy for closed-shell nuclei leads to a higher density of states at a given excitation energy than is present for other nuclei and, hence, leads to a higher probability of formation. An asymmetric mass distribution in good agreement with that observed for the neutron-induced fission of uranium-235 is obtained. Moreover, the changes in the mass distribution with an increased excitation energy of fission (e.g., an increase in the probability of symmetric fission relative to asymmetric fission) are accounted for by the decrease in importance of the shell effects as the excitation energy increases. Other features of the fission process also are qualitatively explained; however, extensive changes in the parameters of the model are required to obtain agreement with experiments for other fissionable nuclides. Then, too, there are fundamental problems concerning the validity of some of the basic assumptions of the model. The fundamental question as to the validity of models that evaluate the properties of the system at the scission point (the so-called scission-point models of fission) is whether the system remains long enough at this point on the steep decline of the potential-energy surface for a quasi-equilibrium condition to be established. There is some evidence that such a condition may indeed prevail, but it is not clearly established. Nonetheless, such models have proved quite useful in interpreting observations of mass, charge, and kinetic energy distributions, as well as of neutron emission dependence on fragment mass. It seems very likely that the fragment shell structure plays a significant role in determining the course of the fission process. Although the single-particle models provide a good description of various aspects of nuclear structure, they are not successful in accounting for the energy of deformation of nuclei (i.e., surface energy), particularly at the large deformations encountered in the fission process. A major breakthrough occurred when a hybrid model incorporating shell effects as a correction to the potential energy of the liquid-drop model was proposed by the Russian physicist V.M. Strutinskii in 1967. This approach retains the dominant collective surface and Coulomb effects while adding shell and pairing corrections that depend on deformation. Shell corrections of several million electron volts are calculated, and these can have a significant effect on a liquid-drop barrier of about 5 MeV. The nucleon numbers at which the shells appear depend on the deformation and may differ from the spherical model magic numbers. In the vicinity of the fission barrier, the shells introduce structure in the liquid-drop potential-energy curve, as illustrated in . The relative heights and widths of the two peaks vary with the mass and charge of the fissioning system. The double-humped barrier (spontaneous fission isomers, for example, is understood as the consequence of the population of states in the second well (class II). These isomers have a much smaller barrier to penetrate and so exhibit a much shorter spontaneous fission half-life. The change in shape associated with these states, as compared to class I states, also hinders a rapid return to the ground state by gamma emission. (Class II states are also called shape isomers.) The systematics of neutron-induced fission cross sections and structure in some fission-fragment angular distributions also find an interpretation in the implications of the double-humped barrier.) provides a satisfactory explanation for a number of puzzling observations in fission. The existence of short-lived, The Strutinskii procedure provided a strong stimulus for calculations of the potential-energy surfaces appropriate to fissioning systems, since it provided a consistent and useful prescription for treating both the macroscopic (liquid-drop) and microscopic (single-particle) effects in deformed nuclei. Many calculations of the potential-energy surface employing different model potentials and parameters have been carried out as functions of the shapes of the system. The work of the American nuclear physicists W.J. Swiatecki, James R. Nix, and their collaborators has been particularly noteworthy in such studies, which also include some attempts to treat the dynamical evolution of the fission process. Calculations for the actinide elements indicate that, at deformations corresponding to the second barrier (incipient formation of two fragments very well. In fact, a discontinuity occurs at the scission point, and the results of the calculation depend on whether the scission configuration is treated as one nucleus or as two separate nuclei.), the potential energy for asymmetric mass splits is lower than that for symmetric ones; hence, the former are favoured at that stage of the process. For larger deformations, however, a single potential does not represent the A two-centre potential may also be used to represent the nature of the forces at work in a fissioning nucleus. In such a model, the potential energy surfaces are represented by two overlapping spheres or spheroids. It is equivalent to a one-centre potential when there is a complete overlap at small deformations, and it has the correct asymptotic behaviour as the nascent fragments separate. This approach indicates a preformation of the final shell structure of the fragments early in the process. Although the validity of the assumptions inherent in scission-point models may be in question, the results obtained with them are in excellent agreement with observation. Representative of such a model is the Argonne Scission-Point model, which uses a macroscopic-microscopic calculation with deformed fragment shell and pairing corrections to determine the potential energy of a system of two nearly touching spheroids and which includes their interaction in terms of a neck connecting them. Models of this kind provide a simple approach to a highly quantitative and detailed study of the dependence of the probability of formation of a given fragment pair on the neutron and proton number and on the deformation in each fragment. They account very well for the mass, charge, and kinetic-energy distributions and the neutron-emission dependence on mass number for a broad range of fissioning nuclei. The scission-point models, however, do not address questions of fission probability or the angular distributions of the fragments. As the fission-excitation energy increases, the shell correction diminishes and the macroscopic (liquid-drop) behaviour dominates. Nuclides in the region of fermium-264 have been observed to undergo symmetric fission with unusually high fragment kinetic energies. This appears to be the consequence of the stability for the magic number configurations of 50 protons and 82 neutrons. The formation of two doubly magic fragments of tin-132 is strongly favoured energetically, whereas the formation of only one such fragment in the low-energy fission of uranium or plutonium isotopes is not. The fragments of tin-132 are spherical rather than deformed, and a more compact configuration at the scission point (with the charge centres closer together) leads to higher fragment kinetic energies. It is evident that shell effects, both in the fissioning system at the saddle point and in the deformed fragments near the scission point, are important in interpreting many of the features of the fission process. The stage of the process at which the various fragment distributions are determined is, however, not clearly established. All the components of a reasonable understanding of fission seem to be at hand, but they have yet to be synthesized into a complete, dynamic theory. Considerations of the dynamics of the descent of the system on the potential-energy surface from the saddle point to the scission point involve two extreme points of view. An “adiabatic” approximation may be valid if the collective motion of the system is considered to be so slow—or the coupling between the collective and internal single-particle degrees of freedom (i.e., between macroscopic and microscopic behaviour) so weak—that the fast single-particle motions can readily adjust to the changes in shape of the fissioning nucleus as it progresses toward scission. In this case, the changes in the system take place without the gain or loss of heat energy. The decrease in potential energy between the saddle and scission points will then appear primarily in the collective degrees of freedom at scission and be associated with the kinetic energy of the relative motion of the nascent fragments (referred to as pre-scission kinetic energy). On the other hand, if the collective motion toward scission is relatively fast or the coupling-to-particle motion stronger, collective energy can be transformed into internal excitation (heat) energy of the nucleons. (This is analogous to heating in the motion of a viscous fluid.) In such a “non-adiabatic” process the mixing among the single-particle degrees of freedom may be sufficiently complete that a statistical model may be applicable at the scission point. Either extreme represents an approximation of complex behaviour, and some experimental evidence in support of either interpretation may be advanced. As in most such instances in nature, the truth probably lies somewhere between the extremes, with both playing some role in the fission process.
Scale are an important part of music lessons. Unfortunately, most music teachers do little more than drill scales and drive kids crazy. The Scale Sleuth™ \| Musical Scales: Breaking the Code (Workbook) from MakingMusicFun.net provides music students with “light bulb” moments – helping kids to understand why the study of scales is important, why composers use so many different scales, and how they can build them themselves – by breaking the secret code. The Scale Sleuth workbook includes: • Worksheet 1: Major Scales • Worksheet 2: Minor Scales • Worksheet 3: Egyptian, Octatonic, Blues, Whole Tone and Pentatonic Scales • Answer Key Worksheet 1: Major Scales introduces students to the major scale. It shows them the whole and half step pattern for the major scale, providing examples, and then gives students a chance to practice writing a few major scales themselves. The worksheet concludes with a “Scales in Action” example showing students that the melody for Joy to the World begins with a complete descending major scale. Scale Sleuth™ \| Musical Scales: Breaking the Code takes the “boring out of scale study, and is a great addition to piano teacher libraries! Browse More Piano Sheet Music and Music Theory Posts: Flash Frog™ \| Music Flash Cards for Beginners Teaching Dynamics: Linking the Visual Arts to Music Pirate Quest \| Musical Terms Board Game (Digital Print) Carnegie Hall Park (Matchbox Parking) \| Music Theory Board Game Free Beginner Piano Sheet Music/Level 1 Free Beginner Piano Sheet Music/Level 2 Free Easy Piano Sheet Music/Level 3 Free Easy Piano Sheet Music/Level 4 Free Easy Piano Sheet Music/Level 5
One of the defining qualities that separate human beings from other members of the animal kingdom is our sophisticated (and constant) use of language. We are born with an intrinsic need to communicate our thoughts, needs, desires, and ideas to others. The young child, naturally possessing this human tendency, and aided by the absorbent mind, is driven to develop the skills of his or her native language. The Language Area is home to some of the most important lessons learned in a child’s life and encompasses both receptive (listening and reading) and expressive (speaking and writing) skills. A typical 3-year-old student understands and responds to the oral language surrounding him or her. But something changes as the child begins to develop the skills of reading and writing. They delight the student and confer whole new levels of freedom and independence that – in turn – encourage even further learning and growth. In her early years, Dr. Montessori discovered that young children were far more capable and interested in developing writing and reading skills than traditional educators expected. She found that when the hand and the mind are prepared side-by-side, reading and writing occur quite naturally and even tend to support one another. Montessori classrooms offer numerous activities to build the muscular strength and motor coordination needed for writing. Using the Sandpaper Letters, for example, children are given a tactile guide as to the proper formation of written letters while also learning to associate the letter symbol with specific letter sounds. Once the child knows a few sounds and can recognize them by sight and sound, he or she is often able to identify them in other words (both written and spoken) and, before you know it, can blend those sounds together into words of their own. The goal of Montessori’s Language Area is to nurture the child’s natural interest in language so that he or she develops a love for reading, learning, and self-expression that can be treasured – and built upon – through his or her entire life. Although each child absorbs and acquires language at his or her own pace, Montessori’s multi-age classrooms foster development by way of the constant exposure to older students who are already decoding words, reading, and writing sentences. At Von Wedel, we begin to teach “reading” as soon as that interest is first expressed. - Vocabulary development - Relationship of symbol-to-sound and sound-to-symbol (Sandpaper Letters) - Recognize letters and sounds (ABC Board, Moveable Alphabets) - Blending sounds together into words - Pincer-grip activities from Practical Life - Tracing Sandpaper Letters - Shaping letters in sand - Shaping letters on boards - Shaping letters (and words) on paper - Understanding parts of speech: nouns, verbs, etc. - Using concrete symbols to represent parts of speech - Sentence analysis - Advanced blending (CVC Words, Pink Series, Word Ladders) - Combining words into sentences - Using readers and workbooks - Putting words together to form a sentence - Describing a picture in a sentence - Answering a question in a sentence - Combining sentences in a paragraph At Von Wedel, the Language Area is easy to find. You will see tall, wooden ABC Boards; shelves lined with Sound Boxes and large trays of Moveable Alphabets used for working with letters and words; Boxes of letters/words for teaching Word Families; Word Ladders that support phonics and spelling; the Pink, Blue, and Green Series for reinforcing short vowel sounds, consonant blends, and phonetic combinations; the Metal Insets for developing hand-muscle skills; Boards for writing; writing strips for combining words into sentences; and materials for writing longer compositions and/or stories.
\|Named By:\|\|William Jacob Holland in 1909\| \|Time Period:\|\|Late Cretaceous, 82-73 Ma\| \|Size:\|\|Estimated at around 10 meters long. Some estimates push this to 12 meters long, but lack of complete fossil material leaves the exact size unknown\| \|Fossil(s):\|\|Teeth, osteoderms and fragmentary skull material\| \|Classification:\|\|\| Chordata \| Sauropsida \| Crocodilia \| Eusuchia \| Alligatoroidea \|\| Deinosuchus ( DY-na-SEW-kas) is an extinct genus related to the alligator that lived 82 to 73 million years ago (Ma), during the late Cretaceous period. The name translates as "terrible crocodile" and is derived from the Greek deinos (deinos), "terrible", and soukhos (soukhos), "crocodile". The first remains were discovered in North Carolina (United States) in the 1850s; the genus was named and described in 1909. Additional fragments were discovered in the 1940s and were later incorporated into an influential, though inaccurate, skull reconstruction at the American Museum of Natural History. Knowledge of Deinosuchus remains incomplete, but better cranial material found in recent years has expanded scientific understanding of this massive predator. Although Deinosuchus was far larger than any modern crocodile or alligator, with the largest adults measuring 10.6 m (35 ft) in total length, its overall appearance was fairly similar to its smaller relatives. It had large, robust teeth built for crushing, and its back was covered with thick hemispherical osteoderms. One study indicated Deinosuchus may have lived for up to 50 years, growing at a rate similar to that of modern crocodilians, but maintaining this growth over a much longer time. Deinosuchus fossils have been described from 10 US states, including Texas, Montana, and many along the East Coast. Fossils have also been found in northern Mexico. It lived on both sides of the Western Interior Seaway, and was an opportunistic apex predator in the coastal regions of eastern North America. Deinosuchus reached its largest size in its western habitat, but the eastern populations were far more abundant. Opinion remains divided as to whether these two populations represent separate species. Deinosuchus was probably capable of killing and eating large dinosaurs. It may have also fed upon sea turtles, fish, and other aquatic and terrestrial prey.
Since 1958, a continuous measurement of the carbon dioxide content of the atmosphere has been made at Mauna Loa Observatory in Hawaii. These observations were initiated by Charles Keeling, who died in 2005, and have been maintained by his son Ralph ever since. Sunshine is a manifestation of solar radiation and when it is absorbed by the surface of the Earth, the surface heats up and emits a different kind of radiation, known as infrared radiation. Carbon dioxide is a special chemical in that it is transparent to solar radiation and yet it absorbs infrared radiation. Thus, the presence of carbon dioxode in our atmosphere allows sunshine to penetrate to the surface but inhibits the emission of infrared radiation to space. The consequence of the absorption of infrared radiation by carbon dioxide in the atmosphere is that Earth is much warmer than it has any right to expect based upon its distance from the Sun. In fact, Earth’s average surface temperature is 59 degrees Fahrenheit when it would be 0 if carbon dioxide and other such greenhouse gases (like water vapor and methane) did not exist in our atmosphere. When Keeling began his measurements in 1958, the atmosphere contained 315 carbon dioxide molecules for every million molecules of gaseous atmosphere. April 2014 was the first month in 56 years in which the monthly average carbon dioxide fraction topped 400 molecules per million (it was 401.33). The continual increase in this carbon dioxide fraction is considered to be the main contributor to the global temperature increase known as global warming. Such values are a first in human history and likely represent the highest carbon dioxide fraction in our atmosphere in at least the last 800,000 years. It is high time that we had a sober, data-driven discussion about the hazards presented by this dangerous trend. Analytical, skeptical science has to be central to this discussion.
Graphs of proportional relationships When looking at the relationship between two variables it is often useful to construct a table of values to plot a graph. Looking at these graphs, the following rules are deduced: - When n = 1, y is directly proportional to x. - When n > 1, y is directly proportional to x², x³ or any other positive power of x. - When 0 < n < 1, y is directly proportional to any nth root of x. - When n < 0, y is inversely proportional to x or any power of x.
Minor or major, environmental issues affect every living being on earth, be it the smallest parasite or the human race. That is, a small disruption on earth can destruct the very place that cradles the lives of many species. One such issue that largely requires global consideration is deforestation. In simple terms, deforestation means clearing of the forests by logging and/or burning (also called slash and burn) trees. In the present times, trees are being depleted at an alarmingly high rate. As per records, about 50 percent of the total tree covered area has been destroyed, all thanks to human activities. This massive destruction of the rainforests is affecting the biodiversity adversely. There are numerous causes that are leading to deforestation, resulting in various harmful consequences. Read on further to find out the causes and effects of deforestation. - Trees are a major source of lumber that is used for building various materials, such as furniture and paper products. - Forests are cleared to provide accommodation for the expanding urban and residential population. - In most countries, forests are cut down to create plenty of land for grazing cattle. - Another reason for cutting down trees is the utilization of the land for growing crops and other agricultural products. - Developing countries require fuel for cooking and heating purposes and what better than trees can be to serve this requirement. Thus, trees are chopped down to be used as firewood or charcoal. - Forests are also depleted for oil and mining exploitation. - Other reasons for deforestation include slash and burn farming techniques, wildfires, acid rain and making highways and roads. The roots of the rainforest trees and vegetation secure the soil. Cutting them exposes the soil to the sun, making it excessively dry, thereby resulting in an infertile soil. To add on, the soil is washed away by the rain removing with it most of the nutrients. The soil reaching the water makes it muddy, resulting in the death of the fish. Eventually, the rivers become shallow making them unreliable for navigation by the humans. This leads to starvation of the people and an increase in the spread of deadly diseases, such as malaria. Floods & Drought Forests are a life saver, as they absorb a large amount of the rainfall, thereby stopping it from entering the inhabited areas and rivers. The cutting down of trees leads to disruption in the regular flow of water, thus causing floods in some areas, while drought in other areas. Change In The Climate Global warming is one of the largest consequences of deforestation. Since there are fewer trees left for absorbing greenhouse gases like carbon dioxide, these gases are released into the atmosphere, thereby increasing the temperature of the land and water. Also, deforestation leads to releasing of carbon that is stored in the trees in the form of carbon dioxide. Disruption Of The Water Cycle Trees play a major role in balancing the water cycle. The water drawn by the trees through their roots is released into the atmosphere, resulting in rains. However, when tree are cut, the climate gets drier in that area, receiving less rain or no rain at all.
Humanities › History & Culture The Platt Amendment and US-Cuba Relations Share Flipboard Email Print (Original caption) The Duty of the Hour: - To Save Her, Cuba, Not Only From Spain - But from a Worse Fate, published by Keppler & Schwarzmann, May 11, 1898. Lithograph by Holrymple, del.; J. Ottman Lith. Co. The New York Historical Society / Getty Images History & Culture American History Key Events Basics Important Historical Figures U.S. Presidents Native American History American Revolution America Moves Westward The Gilded Age Crimes & Disasters The Most Important Inventions of the Industrial Revolution African American History African History Ancient History and Culture Asian History European History Genealogy Inventions Latin American History Medieval & Renaissance History Military History The 20th Century Women's History View More By Brionne Frazier Politics Expert B.A., International Relations, Brown University Brionne Frazier is a history and politics writer specializing in international security and society. She has covered topics including nuclear policy, organized crime, and climate policy. our editorial process Brionne Frazier Updated August 14, 2019 The Platt Amendment set the conditions to end the United States military occupation of Cuba and was passed at the end of the Spanish-American War of 1898, which was fought over which country should oversee the governing of the island. The amendment was intended to create a path to Cuban independence while still allowing the U.S. to have an influence in its domestic and international politics. It was in effect from February 1901 until May 1934. Historical Background Prior to the Spanish-American War, Spain had control over Cuba and was profiting greatly from its natural resources. There are two major theories as to why the U.S. entered war: promoting democracy abroad and gaining control of the island’s resources. First, the War of 1898 was popular with Americans because the government promoted it as a liberation war. Cubans and the well-known liberation force Cuba Libre began revolting against Spanish rule much earlier, in the 1880s. Additionally, the U.S. was already involved in conflicts with Spain throughout the Pacific in the Philippines, Guam, and Puerto Rico, citing the European nation as an imperialist and undemocratic power. Therefore, some historians and politicians theorize that the war intended to promote democracy and extend the reach of the Free World, and the subsequent Platt Amendment was intended to provide a pathway to Cuban sovereignty. However, keeping Cuba in the U.S. sphere of influence had great economic and political benefits. In the 1980s, the U.S. was suffering one of the greatest economic depressions in its history. The island had tons of cheap tropical agricultural products that Europeans and Americans were willing to pay high prices for. Further, Cuba is only 100 miles from the southernmost tip of Florida, so keeping a friendly regime protected the nation’s national security. Using this perspective, other historians believe that the war, and by extension the Platt Amendment, was always about increasing American influence, not Cuban liberation. At the end of the war, Cuba wanted independence and self-government, whereas the United States wanted Cuba to be a protectorate, a region with a mix of local autonomy and foreign oversight. The initial compromise came in the form of the Teller Amendment. This stated that no country can permanently hold Cuba and a free and independent government will take over. This amendment was not popular in the U.S. because it seemingly barred the nation’s annexation of the island. Though President William McKinley signed the amendment, the administration still sought annexation. The Platt Amendment, signed in February 1901, followed the Teller Amendment to give the United States more oversight of Cuba. What the Platt Amendment Says The Platt Amendment’s primary stipulations were that Cuba became unable to enter into treaties with any foreign nation other than the U.S., the U.S. has a right to intervene if it is believed to be in the island’s best interest, and all conditions of the amendment must be accepted in order to end military occupation. While this was not the annexation of Cuba and there was a local government in place, the United States had much control over the island’s international relationships and domestic production of agricultural goods. As the United States continued to expand its influence throughout Latin American and the Caribbean, Latin Americans began to refer to this style of government oversight as “plattismo.” Long-Term Impact of the Platt Amendment The Platt Amendment and military occupation of Cuba is one of the leading causes of later conflict between the U.S. and Cuba. Opposition movements continued to expand across the island, and McKinley’s successor, Theodore Roosevelt, put a U.S.-friendly dictator named Fulgencio Batista in charge in hopes of countering the revolutionaries. Later, President William Howard Taft went as far as to say that independence would be completely out of the question if the Cubans continued to rebel. This only increased the anti-U.S. sentiment and propelled Fidel Castro to the Cuban Presidency with a communist-friendly regime after the Cuban Revolution. Essentially, the legacy of the Platt Amendment is not one of American liberation, as the McKinley administration had hoped. Instead, it stressed and eventually severed the relationship between the U.S. and Cuba that has not normalized since. Sources Pérez Louis A. The War of 1898: the United States and Cuba in History and Historiography. University of North Carolina, 1998.Boot, Max. The Savage Wars of Peace: Small Wars and the Rise of American Power. Basic Books, 2014.
The two regions are geographically completely different but even so it has been a puzzle. A new report by Richard Bintanja, lead author of the study at the Royal Netherlands Meteorological Institute shows that the permanent glaciers in the sea are melting from the bottom. This is caused by warmer sea currents melting the glacier ice and the fresh water released is floating over the colder, more dense, sea water and therefore it is more vulnerable to freezing by the cold winter conditions. This has caused more ice to form. Scientist, Paul Holland of the British Antarctic Survey has shown that the increased wind speed around Antarctica is blowing the fresh surface ice away from the land and this has caused the ice to spread over a larger area. Which ever is the dominant factor the sea ice melts in the summer and ultimately will be overcome by a warmer World and the area will start to reduce.
What is domestic violence? Domestic violence is a pattern of coercive behavior used by one person in order to maintain power and control in an intimate relationship. Domestic violence includes actual or threatened physical, sexual, psychological or economic abuse. It occurs between persons who are current or former sexual, intimate partners or who live in the same household, regardless of sexual orientation. Victims and abusers come from all age groups and social classes. Ninety-five percent of victims of domestic violence are women. Domestic violence is not physical violence alone. Domestic violence is any behavior the purpose of which is to gain power and control over a spouse, partner, girl/boyfriend or intimate family member. Abuse is a learned behavior; it is not caused by anger, mental problems, drugs or alcohol, or other common excuses. When the general public thinks about domestic violence, they usually think in terms of physical assault that results in visible injuries to the victim. This is only one type of abuse. There are several categories of abusive behavior, each of which has its own devastating consequences. Lethality involved with physical abuse may place the victim at higher risk, but the long term destruction of personhood that accompanies the other forms of abuse is significant and cannot be minimized. Please explore the following sections to learn more about how to identify domestic violence. Types of Abuse: - Physical Abuse - Sexual Abuse - Emotional Abuse & Intimidation - Verbal Abuse: Coercion, Threats, & Blame - Economic Abuse Control Controlling behavior is a way for the batterer to maintain his/her dominance over the victim. Controlling behavior, the belief that he/she is justified in the controlling behavior, and the resultant abuse is the core issue in abuse of victims. It is often subtle, almost always insidious, and pervasive. This may include but is not limited to: - Checking the mileage on the odometer following his/her use of the car. - Monitoring phone calls, using caller ID or other number monitoring devises, not allowing them to make or receive phone calls. - Not allowing them freedom of choice in terms of clothing styles, makeup or hairstyle. - Calling or coming home unexpectedly to check up on him/her. This may initially start as what appears to be a loving gesture, but becomes a sign of jealousy or possessiveness. - Invading their privacy by not allowing them time and space of their own. - Forcing or encouraging his/her dependency by making them believe that they are incapable of surviving or performing simple tasks without the batterer or on their own. - Using the children to control the other parent by using the children as spies, threatening to kill, hurt or kidnap the children, physical and/or sexual abuse of the children, and threats to call Child Protective Services if the other parent leaves the relationship. Physical Abuse Physical abuse is any physically aggressive behavior, withholding of physical needs, indirect physically harmful behavior, or threat of physical abuse. This may include but is not limited to: - Hitting, kicking, biting, slapping, shaking, pushing, pulling, punching, choking, beating, scratching, pinching, pulling hair, stabbing, shooting, drowning, burning, hitting with an object, threatening with a weapon, or threatening to physically assault. - Withholding of physical needs including interruption of sleep or meals, denying money, food, transportation, or help if sick or injured, locking victim into or out of the house, refusing to give or rationing necessities. - Abusing, injuring, or threatening to injure others like children, pets, or special property. - Forcible physical restraint against another person's will, being trapped in a room or having the exit blocked, being held down. - The batterer hitting or kicking walls, doors, or other inanimate objects during an argument, throwing things in anger,destruction of property. - Holding the victim hostage. Sexual Abuse Sexual abuse is using sex in an exploitative fashion or forcing sex on another person. Having consented to sexual activity in the past does not indicate current consent. Sexual abuse may involve both verbal and physical behavior. This may include, but is not limited to: - Using force, coercion, guilt, or manipulation or not considering the victim’s desire to have sex. This may include making them have sex with others, have unwanted sexual experiences, or be involuntarily involved in prostitution. - Exploiting a victim who is unable to make an informed decision about involvement in sexual activity because of being asleep, intoxicated, drugged, disabled, too young, too old, or dependent upon or afraid of the perpetrator. - Laughing or making fun of another’s sexuality or body, making offensive statements, insulting, or name-calling in relation to the victim’s sexual preferences/behavior. - Making contact with the victim in any nonconsensual way, including unwanted penetration (oral, anal or vaginal) or touching (stroking, kissing, licking, sucking or using objects) on any part of the victim’s body. - Exhibiting excessive jealousy resulting in false accusations of infidelity and controlling behaviors to limit the victim’s contact with the outside world. - Having affairs with other people and using that information to taunt the victim. - Withholding sex from the victim as a control mechanism. Emotional Abuse & Intimidation Emotional abuse is any behavior that exploits anther’s vulnerability, insecurity, or character. Such behaviors include continuous degradation, intimidation, manipulation, brainwashing, or control of another to the detriment of the individual. This may include but is not limited to: - Insulting or criticizing to undermine the victim’s self-confidence. This includes public humiliation, as well as actual or threatened rejection. - Threatening or accusing, either directly or indirectly, with intention to cause emotional or physical harm or loss. For instance, threatening to kill the victim or himself, or both. - Using reality distorting statements or behaviors that create confusion and insecurity in the victim like saying one thing and doing another, stating untrue facts as truth, and neglecting to follow through on stated intentions. This can include denying the abuse occurred and/or telling the victim they are making up the abuse. - Consistently disregarding, ignoring, or neglecting the victim’s requests and needs. - Using actions, statements or gestures that attack the victim’s self-esteem and self-worth with the intention to humiliate. - Telling the victim that they are mentally unstable or incompetent. - Forcing the victim to take drugs or alcohol. - Not allowing the victim to practice religious beliefs, isolating them from the religious community, or using religion as an excuse for abuse. - Using any form of coercion or manipulation which is disempowering to the victim. Isolation Isolation is a form of abuse often closely connected to controlling behaviors. It is not an isolated behavior, but the outcome of many kinds of abusive behaviors. By keeping the victim from seeing who they want to see, doing what they want to do, setting and meeting goals, and controlling how they think and feel, the abuser is isolating them from the resources (personal and public) which may help them leave the relationship. By keeping the victim socially isolated the batterer is keeping them from contact with the world which might not reinforce the abuser's perceptions and beliefs. Isolation often begins as an expression of their love for the victim with statements like, "if you really loved me you would want to spend time with me, not your family." As it progresses, the isolation expands, limiting or excluding the victim's contact with anyone but the batterer. Eventually, they are left totally alone and without the internal and external resources to change their life. Some victims isolate themselves from existing resources and support systems because of the shame of bruises or other injuries, the abuser's behavior in public, or the abuser's treatment of friends or family. Self-isolation may also develop from fear of public humiliation or from fear of harm to themselves or others. The victim may also feel guilty for the abuser’s behavior, the condition of the relationship, or a myriad of other reasons, depending on the messages received from the abuser. Verbal Abuse: Coercion, Threats, & Blame Verbal abuse is any abusive language used to denigrate, embarrass or threaten the victim. This may include but is not limited to: - Threatening to hurt or kill the victim or their children, family, pets, property or reputation. - Name calling (‘ugly’, ‘bitch’, ‘whore’, or ‘stupid’) - Telling victim that they are unattractive or undesirable. - Yelling, screaming, rampaging, terrorizing or refusing to talk Economic Abuse Financial abuse is a way to control the victim through manipulation of economic resources. This may include, but is not limited to: - Controlling the family income and either not allowing the victim access to money or rigidly limiting access to family funds. This may also include keeping financial secrets or hidden accounts, putting the victim on an allowance or allowing no say in how money is spent, or making the victim turn their paycheck over to the abuser. Causing the victim to lose a job or preventing them from taking a job. The abuser can make a victim lose their job by making him/her late for work, refusing to provide transportation to work, or by calling/harassing/calling him/her at work. - Spending money for necessities (food, rent, utilities) on nonessential items (drugs, alcohol, stereo equipment, hobbies.) WV Licensed Domestic Violence Programs: \|Beckley - 304-255-2559\| Charleston - 304-340-3549 Elkins - 304-636-8433 Fairmont - 304-367-1100 Huntington - 304-529-2382 Keyser - 304-788-6061 \|Lewisburg - 304-645-6334\| Martinsburg - 304-263-8292 Morgantown - 304-292-5100 Parkersburg - 304-428-2333 Welch - 304-436-8117 Wheeling - 304-232-2748 Williamson - 304-235-6121
Labrador retrievers come in three solid colors: black, yellow and chocolate. Black and chocolate Labradors are eumelanistic colors, with their genes residing on the Brown locus. Yellow labs, however, are a completely different animal. Their color relies on alleles located on the Extension locus, the sole purpose of which is to dampen the effect of black and chocolate genes. With 81 combinations of these three colors being possible, the puppies can be any of a variety of colors. Black Labrador Genetics The black color gene is located at the B locus, the location on the genetic strand for the Brown or eumelanistic series of genes. This color is dominant to chocolate, which resides on the same locus. Because all genes are paired, a dog can appear to be black but still possess a gene for chocolate. A black dog, therefore, can possess two black genes (BB) or one gene for black and one gene for chocolate (Bb). It is the gene at the Extension (E) locus that controls whether a Labrador appears to be black, chocolate or yellow, however. If a Labrador retriever possesses even one dominant of the dominant E allele, then his genes always will produce eumelanin; he will appear to be black or chocolate. A black Labrador can possess either two dominant Extension genes (EE) or one dominant and one recessive gene (Ee). Yellow Labrador Genetics Yellow Labrador retrievers always have two recessive genes at the E locus (ee), meaning that their ability to produce eumelanin is disabled. Such dogs produce a pigment called phaeomelanin in their coats, which causes the coat to have a yellow appearance. Yellow dogs, despite having two recessive genes controlling their coat color, can carry genes for either black or chocolate, as the genes on the E locus only block the black or the chocolate from being expressed. Yellows Carrying Black or Chocolate As noted above, all yellow Labrador retrievers possess a pair of e alleles on the Extension locus. However, a dog who appears yellow also possesses the color genes on the Brown locus, even if the color cannot be expressed. A yellow dog, therefore, possesses the genetic code for black (eeBB or eeBb) or for chocolate (eebb). A Labrador with the double recessive on the E locus still can produce eumelanin in his nose, flews and eye rims, generally causing them to be black in color. A dog who has brown pigment in those areas can be assumed to carry chocolate. The color black is always dominant to yellow in Labrador retrievers. A black Labrador who possesses two copies of the dominant allele at the E locus (EEBB) only can produce black or possibly chocolate puppies when bred to an eeBB, eeBb or eebb yellow Labrador. Yellow puppies only become possible if the black Labrador possesses a recessive copy of the E allele (EeBB) or (EeBb). The percentage of black, chocolate or yellow puppies in any given litter is difficult to predict without knowing what genes are carried by the parents. - feedough/iStock/Getty Images
Presentation on theme: "Backing up and Archiving Data Chapter 1. Introduction This presentation covers the following: – What is backing up – What is archiving – Why are both."— Presentation transcript: Introduction This presentation covers the following: – What is backing up – What is archiving – Why are both necessary? Backing up Backing up data is a practice that all organisations and people who work with data should do. Some people consider data to be a company’s most important asset. The loss of any data can have a detrimental impact on an individual or an organisation (no matter the size). Backing up data is simply making a copy of current data. Backing up There are many causes of data loss: – Loss of power – Hardware failure – File corruption – Viruses – Hackers – Theft of equipment – Sabotage of an employee – Espionage by a rival company – Natural Disaster – Honest blunders! – Accidently misplacing data Backing up Back ups can be used to restore lost files by replacing them with a previously saved file. You might not always get the most up-to-date file but consider the alternative...starting your work from the beginning again! Methods of backing up There are many devices which can be used to back up files: – External memory: Memory cards, USB pen drives – External hard drive – Tape – Making an exact copy of a disk Backing up In the event that you need to find a file which has been backed up you need to be able to find the file you need! This means that back ups need to be organised. If you have made several backups of a file you need to be able to tell which is the most recent backup! Things to consider How often do you need to back up? How far should your backups go? – Days – Weeks – Months Archiving Archiving is for long-term storage of data that is not required immediately. More often than not it is never required again but it kept just in case. Data is often removed from a system and stored separately. Archiving Consider the following example: A school records data about pupils’ performance every year. If they continued to collect data, even after pupils had left school, the system resources would soon diminish. Instead, records about pupils are removed from the system once they leave. However, some data may be archived such as average test scores and achievement rates. The data is not needed immediately but may be useful to keep for the future. Archiving Schools often keep full records about pupils for up to seven years. Schools often receive requests to complete references and use the data in their archives to compile them. Archiving Procedure Copy the file onto the archival media. Verify the copied files (i.e. Making sure the copies are the same). Delete the original records from the system. Reasons for archiving Free up system resources – Less hard disk space required Increase system performance – Searches take less time as their is less data to search through – Takes less time to make backups of the system as there is less to copy! Take note: Using an example, define what is meant by the term ‘back- up’. Using an example, define what is meant by the term ‘archive’. Why is it important to back up data? What is the difference between archiving and back-up of data? What storage medium should be used for archiving? Remember Archiving is removing! Backing up is copying!
USING MINECRAFT TO BUILD Davina Kaiser Dexter Lockett Communities In Schools of Brazoria County Science, Technology, Engineering, Arts and Math are more important than ever in a student’s education. This session will raise awareness of providing innovative, intriguing, and interactive activities to develop high quality after school programming. Minecraft: a game with no rules, and endless imagination OUR GOALS FOR TODAY APPLICATION OF KNOWLEDGE…… Incorporate lessons that allow students to explore their mathematical knowledge with hands-on activities. Minecraft allows students to build whatever they want. Use the game to have them create scale models to practice concepts in measurements, proportions, area and perimeter. The building of scale models might integrate social studies content to allow for cross-curricular connections. Coupled with in-class lessons and activities, Minecraft can help students apply the knowledge they have learned in technological and playful ways. Lesson plans that cause students to think about the knowledge they have about living organisms and habitats. SCIENCE: ORGANISMS AND HABITATS You can contextualize the concept of survival for students by having them play the survival mode, which demands players take into account resources, hunger, tools and more as they build and expand their world. Students have to explore in order to collect resources, and they have to process what they find, such as smelting ore to create metal. DO THE RESEARCH……. Require the students to research as well as apply the knowledge they already have about specific historical events and places. SOCIAL STUDIES: HISTORICAL PLACES There are many already-created structures that you can import into the game and have students explore. From the Roman Coliseum to the Globe Theatre, they can wander through and literally see three-dimensional replications of buildings that are no longer there. You might have students identify aspects of a theater, or use it as a tool for presentations. If you really want to go nuts, have students create these models themselves. TELL THE STORY…… Require the students to read and then recreate the plot or storyline of selected One of the best ways to improve how students display their reading comprehension is asking them to create a visualization. They could reconstruct various settings from the text, and even recreate scenes and plot events. They could also use these recreations to give a presentation or make predictions on what might happen next, and then physically create those predictions in Minecraft.
Treating asthma in children under 5 Asthma in children under 5: Understand symptoms, medications and treatment plans.By Mayo Clinic Staff Asthma is ongoing (chronic) inflammation of airways in the lungs. This inflammation makes the airways vulnerable to episodes of difficult breathing (asthma attacks). Common triggers include allergies, colds and exercise. Asthma is managed by controlling inflammation with drugs, avoiding triggers when possible and using medications to treat asthma attacks. Diagnosing and managing asthma in children under age 5 can be difficult. In infants and young children, the primary symptoms of asthma — wheezing and coughing — may be caused by other conditions. Also, standard diagnostic tests used to measure how well someone is breathing cannot be used easily or accurately with children under age 5. Some treatments available to older children for managing asthma are not recommended for infants and preschool children. For these reasons, the management of asthma in children under 5 requires careful and relatively frequent monitoring. You can help minimize asthma symptoms by following a written asthma action plan you develop with your child's doctor to monitor symptoms and adjust treatment as necessary. Asthma symptoms in children under 5 Common asthma signs and symptoms in children under 5 include: - Wheezing, a high-pitched, whistle-like sound when exhaling - Trouble breathing or shortness of breath - A tight, uncomfortable feeling in the chest The severity and patterns of symptoms may vary: - Worsening of symptoms at night - Short periods of coughing and wheezing between periods of time with no symptoms - Frequent or chronic symptoms with episodes of worse wheezing and coughing - Seasonal changes based on prevalent infections or allergy triggers Asthma symptoms may be triggered or worsened by certain events: - Colds or other respiratory infections - Allergy-causing agents (allergens), such as dust, pet dander or pollen - Activity or exercise - In infants, feeding - Exposure to cigarette smoke or other airborne irritants - Strong emotional reactions, such as crying or laughing - Gastrointestinal reflux - Changes or extremes in weather Severe asthma attacks can be life-threatening and require emergency room treatment. Signs and symptoms of an asthma emergency in children under age 5 include: - Gasping for air - Breathing in so hard that the abdomen is sucked under the ribs - Trouble speaking because of restricted breathing Tests to diagnose and monitor asthma in young children Diagnosis of asthma in children under age 5 can be challenging. The primary symptoms may indicate other conditions. With older children a doctor can use a breathing test that measures how well the lungs work, but these tests are not useful with younger children, who may have trouble following instructions and breathing exactly as directed. If your child under age 5 has symptoms that might indicate asthma, your doctor or asthma specialist will likely use several pieces of information to make a diagnosis. Your doctor will likely ask a number of questions, such as the following: - Is there a family history of asthma? - How often do symptoms occur? - Does coughing wake your child at night? - Do the symptoms accompany a cold or are they unrelated to colds? - How often do episodes of breathing difficulty occur? - How long do they last? - Has your child needed emergency care for breathing difficulties? - Does your child have any known pollen, dust, pet or food allergies? - Is your child exposed to cigarette smoke or other airborne irritants? Other tests may include the following: - Blood test. Your doctor can measure the levels of certain white blood cells that may be elevated in response to infections. - Chest X-ray. A chest X-ray may reveal changes in the lung when asthma is moderate to severe. It may also be used to rule out other conditions. - Allergy test. A skin or a blood test may indicate if your child is allergic to a suspected or likely allergen. If your doctor suspects your child has asthma, he or she will likely prescribe a trial treatment. If your child has relatively mild and infrequent symptoms, he or she may take a short-acting drug. If breathing improves in the time and manner expected for that treatment, the improved breathing would support a diagnosis of asthma. If the symptoms are more regular or severe, your doctor will likely begin a drug for long-term management. Improvement during the next four to six weeks would support a diagnosis and lay the groundwork for an ongoing treatment plan. It's important for you to keep track of your child's symptoms during a treatment trial and to follow instructions carefully. If you have followed the instructions and there is no improvement within the trial period, your doctor will likely consider another diagnosis. Asthma treatment in young children The treatment goals for young children with asthma are to: - Treat inflammation in the airways, usually with daily medication, to prevent asthma attacks - Use short-acting drugs to treat asthma attacks - Avoid or minimize the effect of asthma triggers - Maintain normal activity levels Your doctor will use a stepwise approach for treating your child's asthma. The goal is overall management with a minimum number of asthma attacks that require short-term treatment. This means that initially the type or dosage of treatment may be increased until the asthma is stable. When it is stable for a period of time, your doctor may then step down the treatment, so that your child takes the minimum drug treatment needed to remain stable. If your doctor determines at some point that your child is using a short-acting drug too often, then the long-term treatment will be stepped up to a higher dose or additional medication. This stepwise approach may result in changes up or down over time, depending on each child's response to treatment and overall growth and development, as well as on seasonal changes or changes in activity levels. Medications for long-term control Long-term control, or maintenance, medications are usually taken daily. Types of long-term control medications include the following: - Inhaled corticosteroids are the most commonly used long-term asthma control drugs for children under age 5, as well as the preferred treatment according to the National Asthma Education and Prevention guidelines. Easily administered inhaled corticosteroids available to infants and preschool children include budesonide (Pulmicort Flexhaler, Pulmicort Respules), fluticasone (Flovent HFA) and beclomethasone (Qvar). - Leukotriene modifiers may be added to a treatment plan when an inhaled corticosteroid treatment alone does not result in stable asthma management. The drug montelukast (Singulair) is approved in a chewable tablet form for children age 2 to 6 and in a granular form that can be added to pureed food for children as young as 1. - Long-acting beta agonist is an inhaled drug that can be added to a corticosteroid treatment regimen. The drug salmeterol is a long-acting beta agonist combined with an inhaled corticosteroid as a single-dose inhaled medication (Advair HFA). - Cromolyn, an inhaled drug that blocks inflammation, may be used as an add-on treatment with inhaled corticosteroids in children under 5. However, other long-term asthma treatments in this age group are backed by stronger evidence than is this combination. - Oral corticosteroids are used only when asthma management cannot be controlled with other treatments. These medications — called short-acting bronchodilators — provide immediate relief of asthma symptoms, and effects last four to six hours. Short-acting bronchodilators for asthma include albuterol (ProAir HFA, Ventolin HFA, others) and levalbuterol (Xopenex HFA). For children with mild, intermittent asthma symptoms, the short-acting medication may be the only treatment needed. For young children who have persistent asthma and use long-term control drugs, the short-acting drug is used as a quick-relief, or rescue, medication to treat asthma attacks. It may also be used to prevent asthma symptoms triggered by exercise. Overuse of short-acting medications usually indicates that the long-term control treatment plan needs to be revised. Medication delivery devices Most asthma medications are given with a device called a metered dose inhaler that requires a correctly timed deep breath to get medications to the lungs. Attachments for metered dose inhalers and other devices can make it easier for children under age 5 to get an appropriate dose. These devices include: - Valved holding chamber with mask. A valved holding chamber with a face mask can be attached to a metered dose inhaler. The chamber allows a child to inhale the medication and doesn't allow exhaling into the device. The mask enables your child to take six normal breaths to get the same dosage as inhaling a single large puff of medication. - Nebulizer. A nebulizer turns medications into a fine mist your child breathes in through a face mask. Young children often need to use a nebulizer because it's difficult or impossible for them to use other inhaler devices. Asthma control: Steps for children under age 5 You can best manage your child's asthma by following these tips. Create an action plan Your doctor can help you create a written action plan that you can use at home and share with other family members, friends, preschool teachers and sitters. A thorough plan includes such things as the following: - Your child's name and age - Physician and emergency contact information - The type, dose and timing of long-term medications - The type and dose of rescue medication - A list of common asthma triggers for your child and tips for avoiding them - A system for rating normal breathing, moderate symptoms and severe symptoms - Instructions for what to do when symptoms occur and when to use rescue medication Monitor and record Keep a record of your child's symptoms and treatment schedule to share with your child's doctor. These records can help your doctor determine if the long-term control treatment plan is effective and make adjustments to the plan. Keep appointments as recommend by your doctor to review records and adjust your action plan as necessary. Information you record should include: - The time, duration and circumstances of an asthma attack - Treatment responses to asthma attacks - Medication side effects - Changes in your child's symptoms - Changes in activity levels or sleep patterns Control asthma triggers Depending on the triggers for your child's asthma, make adjustments at home, as well as in child care facilities and other environments, to minimize your child's exposure to triggers. These may include: March 06, 2018 - Cleaning thoroughly to control dust and pet dander - Checking pollen count reports - Removing cleaning products or other household products that may be an irritant - Administering allergy medicine as directed by your doctor - Teaching your child hand washing and other habits to minimize colds - Teaching your child to understand and avoid triggers See more In-depth - Adkinson NF, et al. Diagnosis of asthma in infants and children. In: Middleton's Allergy: Principles and Practice. 8th ed. Philadelphia, Pa.: Saunders Elsevier; 2014. http://www.clinicalkey.com. Accessed Aug. 3, 2016. - Expert panel report 3 (EPR3): Guidelines for the diagnosis and management of asthma. Bethesda, Md.: National Heart, Lung, and Blood Institute. http://www.nhlbi.nih.gov/guidelines/asthma/. Accessed Aug. 3, 2016. - Sawicki G, et al. Asthma in children younger than 12: Initial evaluation and diagnosis. http://www.uptodate.com/home. Accessed Aug. 4, 2016. - Adkinson NF, et al. Management of asthma in infants and children. In: Middleton's Allergy: Principles and Practice. 8th ed. Philadelphia, Pa.: Saunders Elsevier; 2014. http://www.clinicalkey.com. Accessed Aug. 3, 2016. - Sawicki G, et al. Asthma in children younger than 12 years: Treatment of persistent asthma with controller medications. http://www.uptodate.com/home. Accessed Aug. 3, 2016. - Spacers and valved holding chambers (VHCs) for use with metered dose inhalers (MDIs). American Academy of Allergy, Asthma & Immunology. https://www.aaaai.org/conditions-and-treatments/library/asthma-library/spacers-asthma. Accessed Aug. 4, 2016.
SMART RESOURCE \| Basic sight words are essential for reading and writing. Repetition is the key to sight word learning. Games are a hands on and fun way to help students to strengthen their visual memory. The 101 sight words bingo includes five game cards with nine words on each card. The call card words are distinguished by the colour red. Also included is a learning intention card and an I can read these words list for assessment. The resource is an excellent daily activity for the classroom Reading and Writing Management board. SMART RESOURCE \| FONT OPTION: Aussie Alphabet Bingo game includes six picture game cards and letters for the call cards. The sets of letter cards include lowercase letters, uppercase letters and lowercase / uppercase letter cards. To play: a letter card is chosen from the letter card pile; the letter name and letter sound is called; the player with the picture name beginning with that letter places a counter over that picture on their card. BINGO is called by a player when all pictures are cover on their card. SMART RESOURCE \| A set of blue uppercase sketch letters suitable for an alphabet chart or for creating display titles and captions. Simply cut out, laminate for durability, and then the letters are ready for a multiple of uses. SMART RESOURCE \| A set of yellow lowercase sketch letters suitable for an alphabet chart or for creating display titles and captions. Simply cut out, laminate for durability, and then the letters are ready for a multiple of uses.
Collage is one of the most free-form types of art your kids can do. It involves sticking stuff onto a surface to make a picture or pattern. It can be anything! The first step is to collect the raw materials to work with. Getting organized is the hardest part, so start small and grow your collection gradually. Use a large box or laundry basket to hold your recycled cardboard, paper, and wood scraps. Smaller items can be sorted into shoeboxes or plastic ice cream tubs and kept in the larger box. When you want to do collage, just pull out your junk box or basket and everything is handy. There are three basic components to collage: The Surface or Base Heavy paper or light card is much more successful as a base than lightweight paper, which tends to tear. You can also use old cardboard boxes or scraps of plywood. The "Stuff" Itself As for the “stuff,” just about anything will do! A few ideas are: - Paper and card of all kinds including tissue or crepe paper, used gift wrap, greeting cards, candy wrappers, old magazines, junk mail. Paper can be cut, folded or torn. - Fabric scraps, leftover yarn, embroidery thread, buttons. - Packaging materials such as corrugated cardboard, bubble wrap, shredded paper, tape, and string. - Recycled, washed junk like bottle caps and lids. - Natural materials like acorn caps, shells, autumn leaves, dried flowers, seed heads, sycamore seeds, small pine cones, feathers, fleece (natural or dyed), cotton. Children respond particularly well to an attractive array of natural materials, and often produce their most beautiful collage creations from these. When you go out for walks, take along a bag to collect any interesting bits and pieces you find. Being on the lookout for interesting things is also good for children’s observation skills. - Crafts materials like glitter, googly eyes, pipe cleaners, colored matchsticks, little pom-poms, precut shapes etc. Although these are convenient, I like to limit the amount of this type of material, as it doesn’t give as much rein to your child’s imagination as most junk or natural materials. Gluing it Together For younger children, and older children working with flat materials like paper and fabric, put a small quantity of white glue in a yogurt container, and use a flat brush about an inch wide as an applicator. Add more glue as required. Afterwards, wash the brush carefully and throw away the container. Allow plenty of drying time, especially in damp weather. Glue sticks are convenient when traveling, and for sticking work into scrapbooks. However, they don’t have the holding power of white glue. Older children working with chunky materials will work much more quickly and easily with a glue gun. Yes, they may burn themselves at first, but they quickly learn to stay away from the painful end. Make sure to stay with children using a glue gun until they learn to use it properly. If you want to seal and protect your collage when it's done, brush over it with a thin layer of watered-down white glue. A sealant called Mod Podge is made specifically for this purpose. (Compare Prices) You can use the same basic collage technique to create different kinds of artwork. For instance:
Crystals can be divided into four categories based on their structural particles and their different forces: ionic crystals, atomic crystals, molecular crystals, and metal crystals. Solids can be classified into three major categories: crystalline, amorphous, and quasi-crystalline. Solid materials with neatly ordered geometric shapes, fixed melting points and anisotropy are a basic form of material existence. Whether the solid material is crystalline or not can generally be identified by X-ray diffraction. The particles in the internal structure of the crystal (atoms, ions, molecules, atom groups) regularly repeat in the three-dimensional space, form a certain form of the lattice, the appearance of a geometric polyhedron shape. The plane that forms a certain geometric polyhedron is called a crystal plane. Due to the different growth conditions, the crystal may have some distortion in its shape, but the angle (crystal plane angle) between the crystal planes of the same kind is certain, and the crystal plane angle is not known. Change principle. Previous: No Information
By giving us your feedback, you can help improve your www.NOAA.gov experience. This short, anonymous survey only takes just a few minutes to complete 11 questions. Thank you for your input!Give my feedback When you watch the news and see pictures of weather from around the United States or the world, you are seeing data from NOAA’s environmental satellites. NOAA’s environmental satellites provide data from space to monitor the Earth to analyze the coastal waters, relay life-saving emergency beacons, and track tropical storms and hurricanes. NOAA operates two types of satellite systems for the United States - geostationary satellites and polar-orbiting satellites. Geostationary satellites constantly monitor the Western Hemisphere from around 22,240 miles above the Earth, and polar-orbiting satellites circle the Earth and provide global information from 540 miles above the Earth. Satellites enable us to provide consistent, long-term observations, 24 hours a day, 7 days a week. They track fast breaking storms across “Tornado Alley” as well as tropical storms in the Atlantic and Pacific oceans. Data from satellites are used to measure the temperature of the ocean, which is a key indicator of climate change. Satellite information is used to monitor coral reefs, harmful algal blooms, fires, and volcanic ash. Monitoring the Earth from space helps us understand how the Earth works and affects much of our daily lives. A listing of all satellite products is available on the website of NOAA's Satellite and Information Service. NOAA's satellites provide other services beyond just imaging the Earth. Monitoring conditions in space and solar flares from the sun help us understand how conditions in space affect the Earth. Satellites also relay position information from emergency beacons to help save lives when people are in distress on boats, airplanes, or in remote areas. Scientists also use a data collection system on the satellites to relay data from transmitters on the ground to researchers in the field. Historical data from our satellites, and other air-based and ground-based observation platforms, is archived for public use at NOAA’s world-class national data centers. In addition to operating our own satellites, NOAA helps promote and enable commercial uses of satellites and space to benefit the U.S. economy. NOAA provides a voice for the U.S. commercial space industry within government decision making processes. NOAA issues licenses for the operation of commercial imaging satellites. NOAA also plays a key part in the national management of the Global Positioning System, a satellite technology that has become vital to the U.S. economic infrastructure.
The history, theory and use of the engineering slide rule Until about 1980, the engineering student could be recognized by the slide rule case dangling from his or her belt, in addition to the pocket protector, beanie and white socks. Then came the HP-35 pocket calculator: expensive and hungry for batteries, but very handy, and seemingly requiring little skill to operate, which recommended it to the richer and less able students. The prices for a scientific pocket calculator--the calculators that can do trig functions, exponentials and logarithms--fell rapidly, soon approaching the price of the cheaper slide rules, so that everyone could have one. Now, a perfectly useful scientific calculator can be purchased for less than $20. Slide rules disappeared from the engineering student's kit along with socks. The slide rule is still a remarkable instrument, small, light and not requiring batteries or sunlight, and not subject to the laws of decay and disintegration. A fifty-year-old slide rule is as good as a new one. If you have one around, it might be interesting to dig it out and examine it. This paper will give you some hints on how to use it. Slide rules multiply and divide, raise to powers and take roots, and take the place of tables of the trigonometric, logarithmic and exponential functions. They do these things practically instantly, and to a constant precision of about three digits. You have to manage the decimal points yourself, however. The slide rule is based on logarithms. Distances on a number scale are proportional to the logarithms of numbers, instead of to the numbers themselves, as on a linear scale, as found on a ruler, for example. A scale goes from 1 to 10, or 10 to 100, or 0.1 to 1, or any other range of a factor of 10. Natural logarithms (base e = 2.718...) were invented by John Napier in 1614, and common logarithms (base 10) were invented by Henry Briggs in 1617, to facilitate multiplication and division with the then rather new Hindu-Arabic digits 0 to 9. Edmund Gunter (famous for the surveyor's chain) invented a logarithmic scale in 1620, from which distances were taken off with dividers. William Oughtred used two logarithmic scales placed side by side for multiplication and division in 1630. Seth Partridge arranged one scale, the slide, so that it was held within the other, the stock or body, making it much easier to hold a setting. In 1775, John Robertson added the cursor or runner, which allowed setting to be transferred to any of several parallel scales, as well as holding a position while the slide was moved. P. M. Roget devised the log-log scale in 1815, which gave values of ex, permitting the calculation of any power or root of a number. The classic form of the slide rule was due to the 19th-century French engineer Mannheim. There were many different kinds of slide rules, adapted to specialized calculations, but the Mannheim slide rule was a general-purpose instrument for scientific and engineering calculations. Slide rules were manufactured by the suppliers of drafting equipment, such as Dietzgen, Keuffel and Esser and Post in the United States. The body and slide were of wood, with enameled faces. The upper and lower rods of the body were connected by metal end pieces. Clamping screws allowed the rods to be precisely adjusted so they were in register. The cursor was an etched line in a glass plate held in a slide. It was spring-loaded so that the cursor line was accurately perpendicular to the rods and slide. The typical engineer's slide rule had scales 10" (25 cm) in length, making the slide rule about 12" overall, and 1-3/4" to 2" wide. A duplex slide rule had scales on both sides, the usual case for engineering slide rules. Angle divisions were originally in minutes, but decimal divisions gradually became predominant, in decitrig slide rules. In 1950, Post brought out an American version of the bamboo slide rule manufactured by Hemmi of Japan, the Versalog. Bamboo is an excellent material for this purpose, and these slide rules were first-rate, as good as any made, but sold for half the price, about $25. I obtained one when I went off to college, and it is still as good as when it was purchased. It was accompanied by a hard-bound, excellent instruction manual. Pickett and Eckel manufactured slide rules made of magnesium alloy, with scales of black on a yellow background. Traditionally, scales had been blue or red on white. These were a bit more expensive than the Post rules, but were very durable and accurate. Longer slide rules were produced for special purposes, but they were expensive and rather cumbersome to use. The extra significant figure was seldom of much use. If more significant figures were required, 7-place logarithms and an adding machine were the usual choice. Later, mechanical calculators that could multiply and divide were available, but they were very expensive. Shorter slide rules that would fit conveniently in a shirt pocket were, however, quite popular. Pickett brought out a very handy rule with 5" scales. A final development was the replacement of wood, bamboo or magnesium by high-quality plastic, with the upper and lower rods in permanent adjustment. The British Thornton Model AA010 of 1969, a standard 10" rule, is a good example. Pickett produced very serviceable all-plastic simplex slide rules selling for only a few dollars, such as the Microline 120 series. Such slide rules may still be available. In the 1950's, the circular slide rule appeared. The scales were circles, the beginnings meeting the ends. As we shall see, this was quite logical. A 10" scale fit on a 4" diameter disc, and longer scales were made more convenient. There was no longer the problem of the end of a scale sticking out one side or the other; all parts of the scales were always in contact. One kind of circular slide rule had rotating discs on each side of the circular body, and a single cursor. It was used exactly like a straight slide rule. An example was the Fullerton No. 1458, from Japan. Another kind had a solid disc and two cursors. The two cursors could be made to rotate together, or separately, as required. The Pickett 101-C was of this type, with a magnesium alloy disc and black on yellow graduations. These were accurate and easy to use, but did not become as popular as the familiar straight slide rules. Making a slide rule at home is not recommended. Not only are the mechanical arrangements difficult, but the scales must be very accurate. For demonstration purposes, however, logarithmic scales are not too difficult to make, and may help one to understand the principles. The Pickett ES-600 5" slide rule is illustrated below. It has all the scales usually found on an engineering slide rule, 25 in all. The Microline 120 has 9 scales, the ones labelled K, A, B, S, T, CI, C, D and L. It can do trigonometric calculations and common logarithms, but not natural logarithms or raising to any power. The most basic small slide rule may have only 6 scales: A, B, CI, C, D and K. It can do only multiplication and division, squares and square roots, cubes and cube roots. The C and D scales are used for ordinary multiplication and division. The CI scale is like the C scale, but is graduated in the opposite direction. To multiply two numbers, set the cursor over one factor on the D scale. Then move the slide until the other factor is under the cursor on the CI scale. The product is then on the D scale at one end or the other of the C scale, whichever one overlaps the D scale. Note how this adds the distances corresponding to the logarithms, assuming that the scales are extended in both directions in decade after decade. A graduation is given for π. The graduation marked R is at 57.3, the number of degrees in a radian, to facilitate interconversion of degrees and radians. To divide, set the cursor over the dividend on the D scale. Move the slide until the divisor on the C scale is under the cursor, and read the quotient on the D scale at whichever end of the C scale is on the D scale. Since the answer is on the D scale, you can do any number of multiplications or divisions one after the other without writing anything down. This put a premium on expressing solutions in terms of multiplications and divisions, without adding or subtracting, especially in trigonometry. With a little practice, you can easily become proficient in multiplying and dividing with the slide rule. Use the theory to figure out why you are doing things; then do them by rule, to save time and avoid errors. Sines and cosines are found with the S scale, tangents and cotangents with the T scale. If you set an angle on these scales, the trigonometric function is given on the C scale. The range of the sine and cosine, or the tangent and cotangent, are from 0.1 to 1.0. Angles smaller than about 6° are shown on the ST scale (the sine and tangent are about equal in this range). When using this scale, the decimal place is assumed one place to the left, so the range is 0.01 to 0.1. For even smaller angles, you simply assume that the sine or tangent is the angle in radians. The A and B scales are just like the D and C scales, but compressed by a factor of 2, so that they run from 1 to 100. If you set a number under the cursor on the D scale, its square is under the cursor on the A scale. Similarly, if you set a number under the cursor on the A scale, its square root is under the cursor on the D scale. You can multiply and divide with the A and B scales, but not as accurately as with the longer C and D scales. The K scale gives cubes and cube roots in the same way. The Versalog had an R scale twice as long as the D scale, for more accurate square roots. The L scale is a linear scale graduated from 0 to 1, giving the common logarithms of numbers on the C scale, or antilogarithms if read the other way. The DI scale is an inverted D scale, just as CI is an inverted C scale, and is used the same way for facilitating certain calculations. The DF, CF and CIF are C, D and CI scales simply shifted by log π. You can use them for ordinary arithmetic, but their real convenience is that they give an automatic multiplication by π of numbers set on C or D. The log-log scales LL1 to LL3 are calibrated in values of ex (the + scales) or e-x (the - scales) for x from 0.01 to 10 on the D scale. The letter M means 1000. The range is from about 20,000 to 0.00005. If you set a number on the LL scale, its natural logarithm is set on the D scale at the same time. You can multiply or divide this logarithm by another number to find any power or root, and then project the answer back onto the LL scale to read its value. For smaller values of x than 0.01, use the approximation ex = 1 + x + ... . The Versalog had an additional log-log scale for x between .001 and .01. The theory of use of the log-log scales is that x = ab can be written ln x = b ln a, and ln ln x = ln b + ln ln a. The addition of logarithms is done on the slide rule as usual. For electrical engineers, one of the most common calculations done on a slide rule was the conversion of a phasor in rectangular components to a phasor in polar components and vice versa. These conversions were necessary for phasor arithmetic because the rectangular form was adapted to addition and subtraction, while the polar form was convenient for multiplication and division. Of course, one could simply use the ordinary rules for multiplication and division to do this, but there were better ways to do it quickly on a slide rule. First of all, one never used r = √(x2 + y2), which is cumbersome to work out any way you look at it. The angle was first obtained from θ = tan-1 (y/x), and then r = y / sin θ or x / cos θ. To go the other way, x = r cos θ and y = r sin θ were used. The procedure for rectangular to polar conversion was first to set the larger of x or y under the cursor on the D scale. Move the slide so that the other component is under the cursor. Then θ can be read on the T scale above the index of the D scale. Move the cursor back to the component on the D scale, and move the slide until the θ on the S scale is under the cursor. Read r on D at the index of the C scale. To go the other way, set one end of the C scale over r on the D scale. Then set θ as a sine on the S scale, and read y on the D scale. Now set θ as a cosine on the S scale, and read y on the D scale. One could also set r on the DI scale, and read y and x on the DI scale under the index of the C scale. These procedures became automatic after a little practice. Go through them for the 3, 4, 5 triangle (angle 36.87°) to see how they work. Bad students would muddle through somehow, but good students profited from learning the quick and reliable methods. Scientific pocket calculators have this conversion built-in, incidentally. The British Thornton slide rule had trigonometric scales on the body, but provided special scales for rectangular-polar conversion. Composed by J. B. Calvert Created 19 January 2001 Last revised 10 January 2004
High-tech rockets, expensive propellants and billions of dollars in research aren’t the only things that have advanced space exploration. Plastic materials have played a vital role throughout the history of spaceflight, allowing astronauts to view their surroundings, breathe oxygen and travel comfortably in orbit around the earth, or on the way to the moon. Without plastics, space exploration would not be where it is today. Stronger Helmets & Visors When you think of the first astronauts to visit the moon, images of puffy space suits and large helmets with shiny visors probably come to mind. Those helmets and visors were made from molded plastic materials capable of withstanding the harshness of space. Because of these plastics, astronauts were able to see their surroundings in clarity without the loss of oxygen or debris infiltrating their suits. Much of the protective gear those astronauts wore was also made from plastic, because of its flexibility and reliable functionality. Softer Spacecraft Seating In order to blunt the impact of landings, NASA developed temper foam, also known as memory foam, for spacecraft seating. This open cell polyurethane-silicon plastic made it easier for astronauts to travel to and from space without getting injured or feeling uncomfortable upon re-entry. It’s now used in mattresses and high-end furniture to make it easier for people to sleep, relax and unwind. The protective qualities of plastic make it one of the most useful materials for facilitating spaceflight and exploration. Better Radiation Protection According to Before Its News, aluminum was used heavily in the construction of spacecraft during the early days of the space program. However, aluminum doesn’t have the same shielding and protective capabilities that certain plastics do when it comes to blocking cosmic radiation. This radiation is a major obstacle for prolonged spaceflight and habitation. Plastics have helped scientists create short- and medium-term solutions that protect astronauts from harmful rays. The net benefit of plastic components is safer space travel, with astronauts in orbit for longer periods of time. Space is full of debris that can make seeing through spacecraft portals and spacesuit helmets difficult. That is why scratch resistant lenses are so important to space travel. Plastic coating is used to make lenses scratch resistant, including astronauts’ visors. Without reliable ways to view their surroundings, astronauts would be at a serious disadvantage, which is why plastics have been used in such high frequency in the design of portals, windows and helmet visors. Plastics are often lighter than other materials that would otherwise be used to make spacecraft. The use of lighter materials makes getting rockets and spacecraft off the ground more cost-effective and efficient. Rocket fuel is also highly volatile, meaning the less of it onboard a spacecraft the better for all stakeholders in a space mission. Plastic seals, flooring, seating and instrumentation panels are among the plastic components that have made spacecraft lighter and more nimble. Lighter spacecraft are also easier to move and store, which is a major cost savings for spaceflight agencies. The monetary and safety benefits yielded by plastics are hard to ignore, which is why NASA and other space agencies have leveraged plastics to the hilt. Plastics have been integral in the development of the tools, equipment and transportation needed to explore space. As governmental agencies and private companies continue to push the boundaries of space travel, plastics will continue to enable mankind to make new strides in the depths of space. Questions? Comments? Let us know in the comments section below. Interested in learning more about plastic properties? Download our free guide!
If the Earth is spinning, then what force keeps us and everything else in place? Gravity. In 1666, English scientist, Sir Isaac Newton (the guy who had an apple fall off a tree and land on his head) said the objects on a spinning Earth must be affected by centrifugal force. He thought the objects on the Earth would fly off unless there was a stronger force holding them on. This line of thinking led Newton to come up with the Universal Law of Gravitational Attraction. Newton described the law in the following mathematical way: where F is the force of gravitational attraction, M1 and M2 are the masses of two attracting bodies, and d is the distance between the center of M1 and the center of M2. The larger M1 and M2 are, and the smaller d is, then the greater the F (force of attraction) will be. So, since the Earth is huge compared to a horse or a human or volleyball, the force of attraction to the Earth is huge. When planets are heavy and close together, they will be attracted to each other! Newton also realized that since gravity pulls all objects toward the Earth’s center (known as a radial force), the centrifugal force (the force of the object pulling away as it spins) is greater the farther away the object from the axis of spin. In other words, the centrifugal force is greatest at the equator and less at the poles. The interaction of the two forces causes the Earth to be flatter at the poles and a bit wider at the waistline (equator). This is measured at the Earth’s radius as 6357 km at the poles, but bulges at the equator to 6378 km. The Earth is so big though that it still looks like a perfect sphere from space. An object with size h = 12cm is a distance s = 15cm in front of a converging lens. The lens is L = 18cm in front of a convex mirror. The lens has a focal length fl = 6cm, and the mirror has a radius of R = 48cm. You shine your laser pointer through the flat glass side of a rectangular aquarium at an angle of incidence of 49 ∘ . The index of refraction of this type of glass is 1.50. At what angle from the normal does the beam from the laser pointer enter the water inside the aquarium? Does your answer to part a depend on the index of refraction of the glass? I need help figuring out this problem because I don't understand why I'm getting it wrong. I set the equation up as 1.0sin(49)=1.5sinθ. From that, I got the value 30.2 degrees. The problem is that my online homework says it's wrong. It also says that the answer to part (A) does not depend on the index of refraction of the glass. What is going on?• Join Chegg Study and get: Guided textbook solutions created by Chegg experts Learn from step-by-step solutions for 9,000 textbooks in Math, Science, Engineering, Business and more 24/7 Study Help Answers in a pinch from experts and subject enthusiasts all semester long
Volcanoes Influence Climate How Volcanoes Influence Climate Over Shorter Timescales The gases and dust particles thrown into the atmosphere during volcanic eruptions have an effect on climate. For the most part they cool the planet by shading incoming solar radiation. This affect can last for months to years, depending on the characteristics of the eruption. Eruptions in the tropics can have an effect on the climate of both hemispheres. Volcanic eruptions at mid or high latitudes only have an effect on the hemisphere they are within. Volcanoes have also caused global warming over long geologic time scales when extreme amounts of volcanism occurred. Particles of dust and ash Volcanic dust (ash) released into the atmosphere during volcanic causes temporary cooling. Larger particles have little effect because they fall out of the air quickly. Small ash particles in the troposphere form a dark cloud that shades and cools the area directly below. These particles will fall out of the atmosphere in rain a few hours or days after the event. The dust that causes the most cooling is that which gets into the stratosphere. It can stay in the stratosphere for months, blocking sunlight and causing cooling over large areas of the Earth. Ash plume from Rabul volcano in Papua New Guinea as seen from the Space Shuttle on 19 September 1994. Credits: NASA A huge cloud of volcanic ash and gas rises above Mount Pinatubo, Philippines, on June 12, 1991. Three days later, the volcano exploded in the second-largest volcanic eruption on Earth in the 20th century. Credits: USGS Often, erupting volcanoes emit sulfur dioxide into the atmosphere. Sulfur dioxide is much more effective than ash particles at cooling the climate. The sulfur dioxide moves into the stratosphere and combines with water to form sulfuric acid aerosols. The sulfuric acid makes a haze of tiny droplets in the stratosphere that reflects incoming solar radiation. This causes surface cooling. The aerosols can stay in the stratosphere for up to three years, moved around by winds and causing significant cooling worldwide. Eventually, the droplets grow large enough to fall to Earth. Illustration of production and effect of volcanic aerosols, including SO2. Credits: Windows to the Universe staff (Lisa Gardiner) Images from NASA Space Shuttles reveal the presence of volcanic aerosols after the Mount Pinatubo eruption in 1991. Credits: NASA and Caspar Ammann Volcanoes also release large amounts of greenhouse gases water vapor and carbon dioxide. The amounts put into the atmosphere from a large eruption doesn't change the global amounts of these gases very much very much. However, there have been times during Earth history of intense volcanism that significantly increased the amount of carbon dioxide in the atmosphere and caused global warming. Measuring the Climate Effects of Volcanic Eruptions Not all volcanic eruptions are the same! The characteristics often depend on the type of magma within a volcano. There are three main indices used to assess the effects of volcanic eruptions on climate. Each is described below. The Volcanic Explosivity Index (VEI). - The Level of Atmospheric Perturbation: The Dust Veil Index (DVI) takes into account the amount of material dispersed into the atmosphere and the amount that the material blocks the incoming solar radiation. - The Eruption Characteristics: Total Mass and Explosiveness: The Volcanic Explosivity Index (VEI) ranks volcanic eruptions to assess magnitude, intensity, dispersion and destructiveness. Eruptions are ranked from 1 to 8 with 8 being the most explosive. Eruptions are more explosive at volcanoes with very viscous magmas rich in silicon, aluminum, and sulfur. The viscous magma blocks the volcano's vents and trapped gases are heated, expand, and build pressure in the plugged vent until explosion. To get exploded material into the stratosphere takes an event with a VEI of at least 4. - The Sulfur Release and Transport to Poles: Paleo-evidence of volcanic eruptions is recorded in ice sheets by the deposition of sulfuric acid aerosols. Thus, we have a proxy record of eruptions prior to recorded history. The Ice Core Volcanic Index (IVI) use data from ice cores, mainly based on sulfate levels to assess paleo-volcanic eruptions. Shop Windows to the Universe Science Store! The Fall 2009 issue of The Earth Scientist , which includes articles on student research into building design for earthquakes and a classroom lab on the composition of the Earth’s ancient atmosphere, is available in our online store You might also be interested in: Looking for online content that can be used for a climate change education course or module? Pages linked below can be used to support an introductory climate change education for either a unit or a full...more Leaders from 192 nations of the world are trying to make an agreement about how to limit emissions of heat-trapping greenhouse gases, mitigate climate change, and adapt to changing environmental conditions....more Climate in your place on the globe is called regional climate. It is the average weather pattern in a place over more than thirty years, including the variations in seasons. To describe the regional climate...more Less than 1% of the gases in Earth's atmosphere are called greenhouse gases. Even though they are not very abundant, these greenhouse gases have a major effect. Carbon dioxide (CO2), water vapor (H2O),...more Television weather forecasts in the space age routinely feature satellite views of cloud cover. Cameras and other instruments on spacecraft provide many types of valuable data about Earth's atmosphere...more Predicting how our climate will change in the next century or beyond requires tools for assessing how planet responds to change. Global climate models, which are run on some of the world's fastest supercomputers,...more The world's surface air temperature increased an average of 0.6° Celsius (1.1°F) during the last century according to the Intergovernmental Panel on Climate Change (IPCC). This may not sound like very...more
Gaucher’s disease is a genetically inherited disorder that causes a deficiency in the enzyme glucocerebrosidase. This enzyme is required to break down the fatty substance glucocerebroside. When this enzyme is deficient, glucocerebroside accumulates in certain cells, particularly macrophages. The macrophages become swollen and dysfunctional and form deposits in various important organs and tissues. Gaucher's disease is one of the most common forms of lysosomal storage disease. Diagnosis is usually made based on a combination of physical assessment and laboratory testing. The blood is tested to check the level of glucocerebrosidase and genetic testing can be used to confirm the diagnosis. Individuals planning a family may want to undergo genetic screening if there is a genetic risk factor such as Ashkenazi Jewish heritage or a family history of the condition. Other clinical features that are suggestive of Gaucher’s disease include the following: - Raised alkaline phosphatase - Raised angiotensin-converting enzyme (ACE) - Raised immunoglobulin levels - Other lysosomal enzymes may also be elevated including tartrate-resistant acid phosphatase, human chitinase, hexosaminidase and chitotriosidase. Chitotriosidase is also useful for monitoring a patient’s response to enzyme replacement therapy in Gaucher’s disease. - Gaucher’s disease may also be suspected if cytology studies show the cytoplasm resembles the appearance of crinkled paper and has macrophages laden with glycolipid. Some of the symptoms that may feature in Gaucher’s disease include: - Enlarged liver and spleen - Cirrhosis or scarred liver - Jaundice and other evidence of liver disease - Abdominal pain - Anemia leading to lack of energy and fatigue - Low platelet count and increased bleeding tendency - Low neutrophil count and increased susceptibility to infection - Acute or chronic bone pain - Weak bones that are prone to fracture - Delayed growth in children - Neurological symptoms include impaired hearing, seizures and poor mobility and coordination Reviewed by Sally Robertson, BSc
Children with DCD: At home, at school and in the community (Booklet) This booklet is designed to help parents and educators identify and manage school-aged children who are demonstrating movement problems typical of children with Developmental Coordination Disorder (DCD). Based on research evidence, the purpose of this booklet is to describe common characteristics of children with motor coordination difficulties, to provide guidance for seeking a referral to a physician, to describe the role of occupational therapists and physiotherapists who may work with these children, and to suggest modifications that may improve the ability of children to function at home, at school, and in the community. Some children only experience coordination difficulties while others have associated learning, speech/language, and attention problems. Management of children with DCD varies greatly due to these differences. As a result, particular techniques and strategies may be more appropriate for one child than another. This booklet describes some of the more common techniques and practical suggestions that may be used. An occupational therapist and/or a physiotherapist may wish to highlight or add specific techniques to personalize it for a particular child/student. The authors gratefully acknowledge the many parents, children, educators, colleagues, students, and service providers who have contributed their knowledge and expertise to the development of this booklet. This booklet was developed with support from the Canadian Occupational Therapy Foundation and funding from the Canadian Institutes of Health Research to facilitate early identification of children with DCD. What is Developmental Coordination Disorder? Developmental Coordination Disorder (DCD) occurs when a delay in the development of motor skills, or difficulty coordinating movements, results in a child being unable to perform everyday tasks. A diagnosis can be made by a medical doctor who will ensure: 1) that the movement problems are not due to any other known physical, neurological, or behavioural disorders; and, 2) whether more than one disorder may be present. The characteristics of children with DCD, however, are usually noticed first by those closest to the child because the motor difficulties interfere with academic achievement and/or with activities of daily living (e.g., dressing, playground skills, handwriting, gym activities). DCD is believed to affect 5-6% of school-aged children and tends to occur more frequently in boys. DCD can exist on its own or it may be present in a child who also has learning disabilities, speech/language difficulties, and/or attention deficit disorder. In this booklet, the coordination difficulties that are discussed are those that are most often seen in children with developmental coordination disorder. How Do Coordination Difficulties Occur? There is no simple answer to this question since coordination difficulties can arise for many reasons. Although we do not know for sure what causes motor coordination problems, research suggests that children can experience difficulties in learning how to plan, organize, perform, and/or modify their movements. One thing we know for certain is that children with DCD have difficulty learning new motor skills. They tend to use their vision more than other types of feedback to guide their movements and, because of this, their motor skills may be more like those of younger children. Children with DCD perform inconsistently from one occasion to the next, and they often perform motor skills in the same way over and over again, even when they are unsuccessful. Typically, children with DCD depend on feedback and are not able to predict the outcome of their movements. As a result, they don’t easily recognize movement errors, learn from their mistakes, or correct their movements. The characteristics described above have led researchers to believe that the coordination difficulties of children with DCD may lie not only in learning how to move their bodies but also in learning how to use strategies to problem-solve solutions to motor tasks. Because motor skills do not become automatic for these children, they must devote extra effort and attention to complete motor tasks, even those that have been previously learned. Children with DCD often don’t recognize the similarities of particular motor tasks, and this leads to difficulties transferring their motor learning from one activity to another (e.g., catching a large ball and then catching a small ball). They also have difficulty generalizing their motor learning from one situation to another (e.g., a child approaching a sidewalk curb has to figure out that stepping up onto the sidewalk is similar to climbing stairs). Having to respond to a changing environment (e.g., when catching or hitting a moving ball, or when avoiding others during team play) poses an additional challenge for children with DCD because they find it hard to monitor incoming information from the environment and to make their bodies respond in a timely way. The result of any of these problems is the same: children with DCD appear clumsy and awkward, and will have difficulty learning and performing new motor tasks. Characteristic Features of Children with DCD When describing children with DCD, it is important to recognize that they are a very mixed group. Some children may experience difficulties in a variety of areas, while others may have problems only with specific activities. The following is a list of some of the more common characteristics that may be observed in a child with DCD. - The child may be clumsy or awkward in his/her movements. He/she may bump into, spill, or knock things over. - The child may experience difficulty with gross motor skills (whole body), fine motor skills (using hands), or both. - The child may be delayed in developing certain motor skills such as riding a tricycle/bicycle, catching a ball, jumping rope, doing up buttons, and tying shoelaces. - The child may show a discrepancy between his/her motor abilities and his/her abilities in other areas. For example, intellectual and language skills may be quite strong while motor skills are delayed. - The child may have difficulty learning new motor skills. Once learned, certain motor skills may be performed quite well while others may continue to be performed poorly. - The child may have more difficulty with activities that require constant changes in his/her body position or when he/she must adapt to changes in the environment (e.g., baseball, tennis). - The child may have difficulty with activities that require the coordinated use of both sides of the body (e.g., cutting with scissors, stride jumps, swinging a bat, or handling a hockey stick). - The child may exhibit poor postural control and poor balance particularly in activities that require balance (e.g. stair climbing, standing while dressing). - The child may have difficulty with printing or handwriting. This skill involves continually interpreting feedback about the movements of the hand while planning new movements, and is a very difficult task for most children with DCD. - The child may show a lack of interest in, or avoid, particular activities, especially those that require a physical response. For a child with DCD, performing motor skills requires significant effort. Fatigue and repeated failure may cause the child to avoid participating in motor tasks. - The child may demonstrate a low frustration tolerance, decreased self-esteem, and a lack of motivation due to difficulties coping with activities that are required in all aspects of his/her life. - The child may avoid socializing with peers, particularly on the playground. Some children will seek out younger children to play with while others will play on their own or follow the educator or playground supervisor. This may be due to decreased self-confidence or avoidance of physical activities. - The child may seem dissatisfied with his/her performance (e.g., erases written work, complains of performance in motor activities, shows frustration with work product). - The child may be resistant to changes in his/her routine or in his/her environment. If the child has to expend a lot of effort to plan a task, then even a small change in how it is to be performed may present a significant problem for the child. Other Common Characteristics - The child may have difficulty balancing the need for speed with the need for accuracy. For example, handwriting may be very neat but extremely slow. - The child may have difficulty with academic subjects such as mathematics, spelling, or written language which require handwriting to be accurate and organized on the page. - The child may have difficulty with activities of daily living (e.g., dressing, using a knife and fork, brushing teeth, doing up zippers, organizing a backpack). - The child may have difficulty completing work within an expected time frame. Since tasks require much more effort, children may be more willing to be distracted and may become frustrated with a task that should be straightforward. - The child may have general difficulties organizing his/her desk, locker, homework, or even the space on a page. If a child exhibits any number of the above characteristics and if these problems are interfering with the child's ability to participate successfully at home, at school, or in the community, then it is important to have the child seen by a family doctor or paediatrician. The medical practitioner may then refer the child to a health service provider at a local children’s hospital or treatment centre or to another community agency. It is not uncommon for parents or educators to be told that a child will "grow out" of their difficulties. However, studies have now shown quite conclusively that most children do not outgrow these problems. While children do learn to perform certain motor tasks well, they will continue to have difficulty with new, age-appropriate tasks. It is important to recognize these motor difficulties because children with DCD are more likely to develop academic and behavioural problems, demonstrate low self-esteem, depression, and anxiety, and they are at greater risk of becoming overweight. The Role of Therapists Occupational therapists (OTs) and physiotherapists (PTs) are educated and trained in analyzing motor skill development and also in determining the ability of a child to cope with the demands and activities of everyday life. Both are uniquely suited for making recommendations for the management of a child with movement problems. In today’s health care environment, OTs and PTs often function in the role of consultant; this is particularly true of therapists working within school settings. In a consultant role, the therapist will observe the child performing tasks that are difficult for him/her and make recommendations to his/her parents and educators. These recommendations may include: strategies or accommodations to assist with tasks at home, at school, or in the community; modifications to the child’s environment; ways to promote physical activity and increase participation; guidelines on choosing community leisure and sports activities that are matched to the child’s interests and abilities; and assistance with setting appropriate expectations to ensure success. OTs and PTs can help parents, educators and the child to develop a better understanding of the coordination difficulties that the child is experiencing. It is important that parents and educators identify and learn to manage these problems early in order to prevent secondary complications. The child may need to be taught strategies to compensate for his/her motor problems and must be given adequate opportunities to practice those motor skills that need to be learned. It is important to educate children with DCD so they become aware of their strengths, as well as their limitations, and so that they gain an understanding of ways in which they may compensate for any difficulties. Children will then be more likely to experience success and may be more willing to attempt activities that they find difficult. If a child is experiencing a great deal of difficulty or is demonstrating secondary emotional and behavioral problems, the OT or PT may decide to work with the child individually. The therapist may do some direct skill teaching of motor tasks that the child needs or wants to learn. S/he may also use a cognitive approach that teaches the child problem-solving strategies that will help the child learn new motor tasks (this type of approach requires a therapist to have extra training). In either case, the reasons and plan for treatment will be discussed with the parent and child. Although in most cases the coordination difficulties do not disappear, children can show considerable improvement in their ability to perform specific tasks and can be helped to participate successfully at home, at school, and in the community. The Role of Educators and Parents There are many small modifications that can make life easier for a child with DCD. Here are a few ideas that may be useful; an OT or PT may have additional suggestions. - Encourage the child to participate in games and sports that are interesting to him/her and which provide practice in, and exposure to, motor activities. Physical activity and enjoyment should be emphasized rather than proficiency or competition. - Try to introduce the child to new sports activities or a new playground on an individual basis, before he/she is required to manage the activity in a group. Try to review any rules and routines that are associated with the activity (e.g., baseball rules, soccer plays) at a time when the child is not concentrating on the motor aspects. Ask the child simple questions to ensure comprehension (e.g., "What do you do when you hit the ball?"). Private lessons may be helpful at certain points in time to teach the child specific skills. - The child may exhibit a preference for, and perform better at, individual sports (e.g., swimming, running, bicycling, skiing) rather than team sports. If this is the case, then try to encourage the child to interact with peers through other activities that are likely to be successful (e.g., cubs, music, drama, or art). - Encourage the child to wear clothing to school that is easy to get on and off. For example, sweat pants, sweat shirts, t-shirts, leggings, sweaters, and Velcro shoes. When possible, use Velcro closures instead of buttons, snaps or shoelaces. Teach the child how to manage difficult fasteners when you have more time and patience (e.g., on the weekend, or over the summer) rather than when you are pressured to get out the door. - Encourage the child to participate in practical activities that will help improve his/her ability to plan and organize motor tasks. For example, setting the table, making lunch, or organizing a knapsack. Ask questions that help the child focus on the sequence of steps (e.g., “What do you need to do first?”). Recognize that, if your child is becoming frustrated, it may be time to help or to give specific guidance and direction. - Recognize and reinforce the child’s strengths. Many children with DCD demonstrate strong abilities in other areas – they may have advanced reading skills, a creative imagination, sensitivity to the needs of others, and/or strong oral communication skills. Educators and parents can work together to ensure that the child with DCD experiences success at school. Parents may find it helpful to meet with the educator near the beginning of the school year to discuss their child’s specific difficulties and to make suggestions about strategies that have worked well. An Individualized Education Plan (IEP) may be needed for some children; however, the following accommodations may be sufficient for others. In the Classroom - Ensure that the child is positioned properly for desk work. Make sure that the child's feet are flat on the floor, and that the desk is at an appropriate height with the shoulders relaxed and the forearms comfortably supported on the desk. - Set realistic short-term goals. This will ensure that both the child and educator continue to be motivated. - Provide the child with extra time to complete fine motor activities such as math, printing, writing a story, practical science tasks, and artwork. If speed is necessary, be willing to accept a less accurate product. - When copying is not the emphasis, provide the child with prepared worksheets that will allow him/her to focus on the task. For example, provide children with prepared math sheets, pages with questions already printed, or 'fill in the blank' for reading comprehension questions. For study purposes, photocopy notes written by another child. - Introduce computers as early as possible to reduce the amount of handwriting that will be required in higher grades. Although keyboarding may be difficult initially, it is a very beneficial skill and is a skill at which children with movement problems can become quite proficient. - Teach children specific handwriting strategies that encourage them to print or write letters in a consistent manner. Use thin magic markers or pencil grips if they seem to help the child improve pencil grasp or to reduce pencil pressure on the page. - Use paper that matches the child's handwriting difficulties. For example: i) widely spaced lines for a child who writes with very large lettering; ii) raised, lined paper for a child who has trouble writing within the lines; iii) graph paper for a child whose writing is too large or improperly spaced; iv) graph paper with large squares for a child who has trouble keeping numbers aligned in mathematics. - Focus on the purpose of the lesson. If a creative story is the goal, then accept messy handwriting, uneven spacing and multiple erasures. If the goal is to have the child learn to set up a math problem correctly, then allow time to do it even if the math problem does not get solved. - Consider using a variety of presentation methods when asking the child to demonstrate comprehension of a subject. For example, encourage children to present a report orally, use drawings to illustrate their thoughts, type a story or report on the computer, or record a story or exam on a tape recorder. - Consider allowing the child to use the computer for draft and final copies of reports, stories and other assignments. If it is important to see the “non-edited” product, ask the child to submit both the draft and final versions. - When possible, encourage the child to dictate stories, book reports, or answers to comprehension questions to the educator, a volunteer, or another child. For older children, voice recognition software can be introduced as soon as the child’s voice patterns have matured enough that they are consistent. - Provide additional time, and/or computer access, for tests and exams that require a lot of written output. In Physical Education - Break down the physical activity into smaller parts while keeping each part meaningful and achievable. - Choose activities that will ensure success for the child at least 50% of the time and reward effort, not skill. - Incorporate activities that require a coordinated response from arms and/or legs (e.g., skipping, bouncing and catching a large ball). Encourage children to develop skills using their hands in a dominant/assistant fashion (e.g., using a baseball bat or a hockey stick). - Keep the environment as predictable as possible when teaching a new skill (e.g., place a ball on a T-ball stand). Introduce changes gradually after each part of the skill has been mastered. - Make participation, not competition, the major goals. With fitness and skill-building activities, encourage children to compete with themselves, not others. - Allow the child to take on a leadership role in physical education activities (e.g., captain of the team, umpire) to encourage them to develop organizational or managerial skills. - Modify equipment to decrease the risk of injury to children who are learning a new skill. For example, Nerf balls in graduated sizes can be used to develop catching and throwing skills. - When possible, provide hand-over-hand guidance to help the child get the feel of the movement - for example, by asking the child to help the educator demonstrate a new skill to the class. Also, talk out loud when teaching a new skill, describing each step clearly. - Focus on understanding the purpose and the rules of various sports or physical activities. When a child understands clearly what he/she needs to do, it is easier to plan the movement. - Give positive, encouraging feedback. If providing instruction, describe the movement changes specifically (e.g., “you need to lift your arms higher”). In the Community - Encourage exposure to physical activities for fun and participation, with an emphasis on health and fitness. - Consider lifestyle sports such as swimming, skating, cycling, and skiing to maintain or improve strength and overall endurance. - Keep in mind the potential need for extra support or individual lessons with sporting activities, especially as higher skill levels must be reached. - Ensure safety through the use of protective gear (wrist guards, helmets) with physical activities. - Help coaches, sports instructors, and community leaders understand the child’s strengths and challenges so they can support and encourage them to be successful. - Encourage children to engage in activities that are non-motor based such as music, drama, clubs to promote social experiences and the benefits of social participation. Developmental Coordination Disorder is a motor skill disorder that interferes with children's ability to perform many tasks that are required every day. Children with DCD are a mixed group. Any given child may present with a variety of different problems. Educators and parents who are with a child every day may be the first to notice the difficulties that the child is experiencing. It is important for the child to be seen by a physician at an early age to rule out other medical reasons for their motor difficulties. Children with DCD who are not recognized may experience failure and frustration, are often perceived to be lazy or unmotivated, and may develop additional physical, social, and behavioural problems. Intervention for children with DCD may include referral to an occupational therapist or physiotherapist. An OT and/or PT will help the child learn to perform daily tasks more successfully and will make recommendations to parents and educators regarding the participation of children with DCD at home, in the classroom, on the playground, and in leisure activities in the community. Contrary to the widely accepted belief that children with DCD will outgrow their problems, studies have demonstrated that children may acquire certain skills with extra practice but new motor skills will still be a problem. Children with DCD require early intervention to help them learn strategies to compensate for their coordination difficulties, to feel better about themselves as individuals, and to prevent other secondary issues from developing. Many resources about children and youth with DCD can be found on the CanChild website at: www.canchild.ca (click on “Developmental Coordination Disorder”). - Information for Physicians and other Health Professionals - Flyers and Resources for Educators - Typing/Keyboarding and School-Related Recommendations - Encouraging Physical Activity - List of Books/Other Resources If you have found this booklet to be helpful, please let us know: School of Rehabilitation Science 1400 Main St. West, IAHS Bldg, Rm 408 Hamilton, ON L8S 1C7 © C. Missiuna, L. Rivard & N. Pollock, 2011; CanChild Centre for Childhood Disability Research, McMaster University
When it comes to antennas, smaller is better, according to University of Michigan researchers. In an effort that could impact the size of mobile devices and other equipment, researchers have developed tiny, hemisphere-shaped antennas that maintain the same bandwidth as their larger counterparts. I spoke recently with electrical engineering and computer science professor Anthony Grbic about this work, which was also developed by Stephen Forrest, graduate student Carl Pfeiffer and former Ph.D. student Xin Xu. Below are excerpts from our interview. You developed small, hemisphere-shaped antennas. How did you go about this? My colleague Stephen Forrest and I were at a meeting in Ohio. We drove back together and it was a four-hour trip. We started talking about research, as we like to do. He's in solar cells and things like that. I deal with antennas. You can make some really nice, small antennas if you combine these two things. We were able to perfect this process and make these antennas. The hemispherical shape [of our antennas] takes advantage of volume, essentially. This allows miniaturization. The spiraling effect also contributes to the miniaturization of the antenna. How much smaller are your antennas than typical? The way you quantify it is: For a given bandwidth or data rate, what's the smallest antenna you can build? There's this fundamental limit called the Chu Limit. With these antennas, we're riding right on this Chu Limit. This limit that was established in the 1940s by Chu, we're actually building antennas right at this fundamental limit. The antennas out there, they can be very small but their bandwidth is three or four times smaller. I have a bandwidth that I need -- and we're building the smallest antennas you can make for that given data rate. In terms of size, we built some at cell phone frequencies. This antenna has a radius of about one centimeter. It basically rides this Chu limit. [The maximum cell phone antenna] is about four centimeters. These are light-weight antennas. It's just a thin plastic with a metallic pattern on top. Why was it necessary to shrink antennas? The largest component in a wireless gadget is an antenna. Many times, its footprint limits the size of mobile devices. If we can shrink that, we can shrink a mobile device. I had a friend who was working in antenna design years ago when camera phones came out. When the camera phones came out, you had less space for the antenna. We're adding more and more features to mobile gadgets, so size is becoming an issue. By keeping the footprint the same size, we can pack more in. You mentioned that these antennas are smaller and more lightweight. Are there any other benefits to them? This spiral-type antenna was proposed years ago, but there wasn't a nice way to make these. They were demonstrated by manually spiraling a wire around. The question was: How do we mass produce these things? Using our technology, it's a simple stamping process. You have these hemispheres and you stamp the metallic patterns on to them. It's a very efficient, quick, low-cost way of building antennas. Earlier groups have tried ink jet printing, but the issue there is that the metallic ink has lower conductivity than normal metals. That leads to lower efficiency. In what devices could these antennas be used? We've had some interest from mobile device manufacturers for Bluetooth and WiFi communication. There's interest in putting these antennas on autonomous micro-vehicles. These can be terrestrial or flying. You want to miniaturize your unmanned aeronautical vehicle to minimize detection. What’s next for this work? This antenna operates in one frequency range. The next step is to make an antenna that operates in multiple frequency ranges, so you can use it in multiple applications. Now that we have a method of printing these metallic patterns onto contoured substrates, we'd like to explore conformal antennas. These are antennas that conform to a surface. For example, conformal to the surface of a car or a plane. This would make them low profile. Photo, top: Antenna next to quarter, by Carl Pfeiffer Photo, bottom: Anthony Grbic This post was originally published on Smartplanet.com
North America used to have over 150 species in the genus Aster. But now only one species remains. That isn’t because they went extinct, but instead, they were re-named. Many of these species are still referred to in general as “asters.” Collected on September 22, 1900, this specimen was found in Fern Hollow, Frick Park, Pittsburgh by early museum botanist John Shafer. Eurybia divaricata (formerly Aster divaricatus) is commonly known as “white wood aster.” This beautiful fall blooming plant (like many asters) is a common native in eastern United States forests. So why the new name? Taxonomy (the science of classifying organisms) is an ever-changing science, subject to revision as more research is done, especially at the molecular (DNA) level. As we understand how organisms are related, we can better understand the history of life on Earth. Taxonomic studies of plants often lead to the splitting of one species into many or the lumping of many species into one. In some cases, a “new” rare species may have been hiding under our noses, previously grouped with another species. These studies are important for the conservation and protection of vulnerable species. We must know what these species are to actually protect them! Like most herbaria (plural for herbarium), the Carnegie Museum herbarium is organized by genus within families. Earlier this year, collections manager Bonnie Isaac and a team of interns and volunteers reorganized the sunflower family (Asteraceae), one of the largest families of flowering plants. After a month of reorganizing and renaming folders, the work is still ongoing. No surprise, as this family is represented by over 51,000 specimens (or about 10% of the entire collection)! Ongoing taxonomic rearrangements like these are just one reason why the work of herbarium staff is never done. Botanists at Carnegie Museum of Natural History share pieces of the herbarium’s historical hidden collection on the dates they were discovered or collected. Check back for more!
Size: They can grow up to 20 inches (51 cm), on a diet of mollusks, annelid worms, and other benthic invertebrates. In captivity, its diet should be supplemented with meaty items such as pieces of squid and shrimp (Foster and Smith, 2004). Its mouth is located in the middle of the underside of the cephalothorax. A pair of pincers (chelicerae) for seizing food are found on each side of the mouth. Book gills: Horseshoe crabs possess five pairs of book gills located just behind their appendages that allow them to breathe underwater, and can also allow them to breathe on land for short periods of time, provided the lungs remain moist. Outer Shell: The outer shell of these animals consists of three parts. The carapace is the smooth frontmost part of the crab which contains the eyes, the walking legs, the chelicera (pincers), the mouth, the brain, and the heart. The abdomen is the middle portion where the gills are attached as well as the genital operculum. The last section is the "telson" (caudal spine) which is used to flip itself over if stuck upside down. Eyes: The horseshoe crab has been extensively used in research into the physiology of vision. It has four compound eyes, and each ommatidium feeds into a single nerve fibre. Furthermore the nerves are large and relatively accessible. This made it possible for electrophysiologists to record the nervous response to light stimulation easily, and to observe visual phenomena like lateral inhibition working at the cellular level. More recently, behavioral experiments have investigated the functions of visual perception in Limulus. Habituation and classical conditioning to light stimuli have been demonstrated, as has the use of brightness and shape information by male Limuli when recognizing potential mates. Among other senses, they have a small sense organ on the triangular area formed by the exoskeleton beneath the body near the ventral eyes. Mandibles: Although most arthropods have mandibles, the horseshoe crab is jawless. The horseshoe crab's mouth is located in the center of the body. In the female, the four large legs are all alike, and end in pincers. In the male, the first of the four large legs is modified, with a bulbuous claw that serves to lock the male to the female while she deposits the eggs and he waits to fertilize them. Their body also contains a cartilaginous tissue. Regeneration: Horseshoe crabs possess the rare ability to regrow limbs lost, in a manner similar to sea stars. This attribute was recently proven by Sue Shaller of the United States Fish and Wildlife Service. Medical research: Horseshoe crabs are extremely valuable as a species to the medical research community. Since 1964 a substance made from their blood called Limulus Amebocyte Lysate (LAL) has also been used to test for bacterial endotoxins in pharmaceuticals and for several bacterial diseases. The animals can be returned to water after extraction of a portion of their blood, so this is not necessarily a threat to the survival of horseshoe crabs. A single horseshoe crab can be worth $2,500 over its lifetime for periodically drawing its blood for this extract. Blue blood: The blood of horseshoe crabs is blue, which is a result of its high content in copper-based hemocyanin instead of the iron-based hemoglobin found, for example, in humans. The fact that horseshoe crabs have evolved so little over the past 300 to 400 million years is part of the reason why they are so different from most other animals. Conservation: Limulus polyphemus is not presently endangered, but harvesting and habitat destruction have reduced its numbers at some locations and caused some concern for these animals' future. Since the 1970s, the horseshoe crab population has been decreasing in some areas, owing to several factors, including the use of the crab as bait in conch trapping. In 1995, the nonprofit Ecological Research and Development Group (ERDG) was founded with the aim of preserving the four remaining species of horseshoe crab. Since its inception, the ERDG has made significant contributions to horseshoe crab conservation. ERDG founder Glenn Gauvry designed a mesh bag for conch traps, to prevent other species from taking off with the bait. This has led to the amount of bait needed being decreased by approximately 50%. In the state of Virginia, these mesh bags are now mandatory in conch fishery. The Atlantic States Marine Fisheries Commission is in 2006 considering several conservation options, among them being a two-year ban on harvesting the animals affecting both Delaware and New Jersey shores of Delaware Bay. Every year, around 10% of the horseshoe crab's breeding population dies when rough surf flips the creatures onto their backs, a position from which they often cannot right themselves. In response, the ERDG (Ecological Resource and Development Group) launched a "Just Flip 'Em" campaign, in the hopes that beachgoers will simply turn the crabs back over. Conservationists have also voiced concerns about the declining population of shorebirds, such as Red Knots, which rely heavily on the horseshoe crabs' eggs for food during their Spring migration. Precipitous declines in the population of the Red Knots have been observed in recent years. Predators of horseshoe crabs, such as the currently threatened Atlantic Loggerhead Turtle, have also suffered as crab populations diminish. Horseshoe crabs can live for 20-25 years. They migrate into the shore in late spring, with the males arriving first. The females then arrive and make nests at a depth of 15-20 cm in the sand. In the nests, females deposit eggs which are subsequently fertilized by the male. Egg quantity is dependent on female body size and ranges from 15,000-64,000 eggs per female (Leschen et al. 2006). "Development begins when the first egg cover splits and new membrane, secreted by the embryo, forms a transparent spherical capsule" (Sturtevant). The larvae form and then swim for about five to seven days. After swimming they settle, and begin the first molt. This occurs approximately twenty days after the formation of the egg capsule. As young horseshoe crabs grow, they move to deeper waters, where molting continues. They reach sexual maturity in approximately eleven years and may live another 10-14 years beyond that. Horseshoe crabs are distant relatives of spiders and are probably descended from the ancient eurypterids (sea scorpions). They evolved in the shallow seas of the Paleozoic Era (540-248 million years ago) with other primitive arthropods like the trilobites. Horseshoe crabs are one of the oldest classes of marine arthropods, and are often referred to as "living fossils", as they have not changed much in the last 350 to 400 million years. 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Decontamination should never be performed before stabilizing the patient and obtaining samples of involved areas. Efforts can be divided into two distinct processes, internal and external decontamination. Before continuing with methods of internal and external decontamination, a description of the two is in order. Contamination occurs when an unwanted material remains on or inside the patient. External contamination is located on the surface of the body. This form of contamination is usually easily managed. Radioactive materials are not especially difficult to remove. In most cases, soap and water will remove the external contamination that may be located in the skin or hair. Internal contamination is located internal to the skin and is more difficult to treat because it may have already entered a metabolic pathway. Full knowledge of the chemistry, physiological properties, and modes of excretion is required. This knowledge is available in several texts. Most notably, NCRP #65 (Management of Persons Accidentally Contaminated with Radionuclides) lists many of the biologic pathways for the elements. Radioactive external contamination is often easily treated by using soap and water. The popular movies showing abrasive cleaning of the skin with corn meal and bleach is detrimental. This action may actually cause an easily managed external contamination to become internal contamination. The method for any solution used is the same. Wash, dry, then resurvey. The area should be washed with a clean gauze sponge. The gauze should be wet with the cleaning solution, the affected area gently scrubbed, and then the gauze disposed of. The commonly used technique of wetting the gauze, cleaning the area, rewetting the gauze, and cleaning again should be avoided. The potential for contamination of the basin of cleaning solution occurs when moving back and forth between a contaminated area and the basin. A gauze should be used once, then discarded. The affected area should next be dried thoroughly. Contaminated cleaning solution may remain on the patient. Drying with an absorbent disposable material or gauze will remove any contaminants that were washed off by scrubbing. Finally, when the drying is complete, the area should be resurveyed to check the efficacy of the decontamination efforts. If contamination persists but the amount has decreased, continue using the same solution. If three successive washings do not result in a significant decrease, progression to a different cleaning solution is indicated. The mildest cleaning solution should be the one to start with for intact skin. For treatment of wounds that are contaminated, the cleansing solution normally used for cleaning should beemployed. Betadine is quite effective in its cleaning action and offers the additional protection of blocking the thyroid from any radioactive iodine uptake. Should the first solution not be effective in cleansing, other solutions can be tried. Betadine, hydrogen peroxide, Phisohex, or Dakins solution are also effective cleansers. Persistent contamination on intact skin can sometimes be removed by the use of hand lotion. Internal contamination poses a special problem. The offending agent has passed the protective layer of the skin and is now somewhere inside the patient. The location of the contaminant depends on the chemical composition and its biological distribution. A thorough knowledge of the mechanisms of enhancing excretion of these materials is useful in the therapy of internal contamination. Iodine is almost completely absorbed by the thyroid gland. The iodine not absorbed by the thyroid is excreted primarily via the urine. Since iodine becomes organified within the thyroid, it is imperative to begin treatment early. This is performed by providing the patient with a comparatively large dose of stable iodine. Ten drops of super saturated potassium iodide sloution SSKI in a glass of water or juice followed by three drops per day for three days should suffice to block the thyroid. Treatment with SSKI within the first hour of contamination results in about 90% effectiveness in preventing thyroid uptake. At four hours, it is only about 50% effective. At 24 hours, SSKI offers no benefit in preventing thyroid uptake of iodine. Betadine, as mentioned earlier, offers a certain amount of protection. Iodine is absorbed through intact skin and wounds. Betadine contains enough iodine as to help prevent thyroid uptake of iodine. If iodine contamination is suspected however, treatment with SSKI is suggested. Like iodine, tritium is also absorbed through intact skin. Tritium behaves like water and distributes throughout the fluid spaces of the body. Treatment consists of aggressive fluid replacement and diuresis. Caution should be taken to regularly monitor the electrolytes during this treatment. Strontium behaves like calcium within the body. It is taken up by the bones and incorporated into the bony matrix. To prevent this, calcium can be given to help displace the strontium and enhance the excretion through the kidneys. Many other materials cannot easily be excreted. In these cases, materials such as desferoxamine, EDTA, BAL and other chelating agents can be used to bind the material and promote excretion. Great care must be taken when using these chelating agents as they donot discriminate in what they bind between radioactive and non-radioactive elements. Massive and dangerous electrolyte disturbances may result from the use of these agents. It is possible that a significant amount of material may be inhaled and deposit within the lungs. There is some question if bronchial lavage is indicated in these cases. Alpha emitters that deposit their radiation doses locally may result in pulmonary fibrosis. Bronchial lavage has been proposed as a means by which these contaminants may be removed. Bronchial lavage however is not without complications itself. It may not result in complete removal of the contaminant and may cause significant irritation of the bronchial lining. Its use should be limited to situations where there are large amounts of inhaled contamination. Large doses of radiation exposure that result in the depression of white cells and platelets may require a bone marrow transplant. This too is a procedure that is not to be taken lightly. The complications of bone marrow transplant may be life threatening. Depending on the areas exposed, an autologous transplant may not be possible. Its use should be confined to very high doses of radiation exposure. Transplanatation in the acute radiation syndrome situation is highly controversial.
Phonics at St John Southworth St John Southworth RC Primary School uses a reading scheme called Read Write Inc. Read Write Inc. teaches synthetic phonics in a structured exciting way. Children will start the scheme when they join the school in Reception and will work through the scheme until they can read confidently with good understanding. The scheme also supports children’s writing, giving them the tools to spell and compose. What is synthetic phonics? When your child is learning to read there are two crucial things to learn: – the sounds represented by written letters – how to blend the sounds together to make words. Synthetic Phonics is a way of teaching reading. Children are taught to read letters or groups of letters by saying the sound(s) they represent – so, they are taught that the letter l sounds like llllll when we say it. Children can then start to read words by blending (synthesising) the sounds together to make a word. At school, you will probably hear teachers talking about blending, but you might also hear them refer to sounding out. All these terms focus on the same point – synthesising sounds. Say the sounds There are 26 letters of the alphabet but they make 44 sounds. There are lots of videos that parents can watch to help with the teaching of reading at home. Please go to:
Are Workbooks Helping or Hurting Your Students? Workbooks are mass produced for the masses. They are a one size fits all approach to mastering fundamental skills. Workbooks teach children that reading is about reading a passage and answering questions. Workbooks do not teach children about the many purposes of reading, how to enjoy reading or how to comprehend and read with fluency. If one of your students is struggling to read, or struggles with comprehension, it is not because he or she is unable to be a successful reader, it is because the child has not been taught to read in a way that makes sense to them. When you give a child a workbook expecting them to practice reading and become a better reader, you are setting them up for failure. Workbooks don’t work because they don’t teach your students how to think and problem solve on the run. Instead workbooks provide your students with cookie cutter rote practice. Therefore, if your students are working through a workbook using weak strategies or making the same mistakes over and over, they are only practicing making mistakes. Your students will not become better readers if they don’t learn how to read in a way that builds comprehension, fluency and enjoyment. They will learn to hate reading because repetitive practice is boring. Additionally, if they practice every day with a workbook but do not become a better reader, then your students will begin to see themselves as a failure. It is more important for children to view reading as a means to gather information or as an enjoyable activity. If you want your students to enjoy reading and improve comprehension, you might try setting a purpose for reading. You could also teach your students how to use specific reading comprehension strategies. Reading comprehension strategies include the following: - Make Connections - Ask Questions - Make Predictions - Make Inferences - Identify the Author’s Message - Determine Importance - Understand Text Structure When you teach young readers how to use reading comprehension strategies, you are giving them the tools necessary to fully comprehend and enjoy what they read.
Slavery: Antebellum America's National Institution Driving the deepening U.S. commitment to slavery that took root in the late 18th century were the intertwined investments in the world produced by the enslaved as well as the distinctive American identities produced by defenders of the institution. In both of these respects, slavery was not solely a southern institution but very much a national one. While the presence of slaves and slavery came to define “the South” as a slave region, “the North” was also deeply stained by the institution. Stephanie Camp is the Donald W. Logan Family Endowed Chair in American History at the University of Washington, where she teaches classes on nineteenth-century U.S. history, slavery, African Americans, and gender and the body. She is the author of the prize-winning “Closer to Freedom, Enslaved Women and Everday Resistance in the Plantation South,” and the co-editor of “New Studies in the History of American Slavery.”
- Epilepsy Slideshow - Brain Disorders Image Collection - Take the Epilepsy (Seizure Disorder) Quiz - Find a local Neurosurgeon in your town Quick GuideEpilepsy: Symptoms, Causes and Treatment What Is Epilepsy Surgery? - Surgery to remove the area of the brain producing seizures. - Surgery to interrupt the nerve pathways through which seizure impulses spread within the brain. Surgery is considered only if the area of the brain where the seizures start, called the seizure focus, can be clearly identified, and if the area to be removed is not responsible for any critical functions, such as language, sensation and movement. Extensive evaluation and testing are necessary to determine if surgery is appropriate. Who Is a Candidate for Epilepsy Surgery? Surgery may be an option for people with epilepsy whose seizures are disabling and/or are not controlled by medication, or when the side effects of medication are severe and greatly affect the person's quality of life. Patients with other serious medical problems, such as cancer or heart disease, usually are not considered for epilepsy surgery. What Surgical Options Are Available? Different surgical procedures are available to treat epilepsy. The type of surgery used depends on the type of seizures and the area of the brain where the seizures start. The surgical options include: - Lobe resection: The largest part of the brain, the cerebrum, is divided into four paired sections, called lobes -- the frontal, parietal, occipital and temporal lobes. Temporal lobe epilepsy, in which the seizure focus is located within the temporal lobe, is the most common type of epilepsy in teens and adults. In a temporal lobe resection, brain tissue in the temporal lobe is resected, or cut away, to remove the seizure focus. The anterior (front) and mesial (deep middle) portions of the temporal lobe are the areas most often involved. Extratemporal resection involves removing brain tissue from areas outside of the temporal lobe. - Lesionectomy: This is surgery to remove isolated brain lesions -- areas of injury or defect such as a tumor or malformed blood vessel -- that are responsible for seizure activity. Seizures usually stop once the lesion is removed. - Corpus callosotomy: The corpus callosum is a band of nerve fibers connecting the two halves (hemispheres) of the brain. A corpus callosotomy is an operation in which all or part of this structure is cut, disabling communication between the hemispheres and preventing the spread of seizures from one side of the brain to the other. This procedure, sometimes called split-brain surgery, is for patients with extreme forms of uncontrollable epilepsy who have intense seizures that can lead to violent falls and potentially serious injury. - Functional hemispherectomy: This is a variation of a hemispherectomy, a radical procedure in which one entire hemisphere, or one half of the brain, is removed. With a functional hemispherectomy, one hemisphere is disconnected from the rest of the brain, but only a limited area of brain tissue is removed. This surgery generally is limited to children younger than 13 years old who have one hemisphere that is not functioning normally. - Multiple subpial transection (MST): This procedure is used to help control seizures that begin in areas of the brain that cannot be safely removed. The surgeon makes a series of shallow cuts (transections) in the brain tissue. These cuts interrupt the movement of seizure impulses but do not disturb normal brain activity, leaving the person's abilities intact.
Coaching A Preschool Child Handwriting and Reading Readiness There are two related issues that cause difficulties for a beginner - perception and ergonomics. Simple instruction can help your child learn correct movement patterns. Learning correct patterns in the beginning eliminates any need to relearn. It makes sense that this would present a great advantage for language skill development. A left-handed child faces some special obstacles relating to directionality and ergonomics. If your child is left-handed please visit this link to learn specific coaching techniques - Coaching Position Skills. A Toy Dinosaur No wonder so many little ones have trouble learning the difference between letters d, b, and p when they are limited to a visual recognition process. This brings us to the link between physical and visual that can improve recognition fluency. Use the image of the letter to the right. Move your cursor to the spot where the letter starts and click that spot. A new window will open and display an animation. The fact that you can choose a start point means that you are "seeing" movements even though the image is static. The movements are in the handwriting motor patterns you learned. Others may well have chosen a different start point because they learned a different process for production. There are actually three different "hot" start points on the image. Each presents commonly used production processes. Only one movement process best supports the top down, left to right pattern of our language. The others present movements that would conflict with fluent ocular tracking. Please go back to the original image and search for the other two hot links. Invention or Instruction? What Should You Do? This simple, four-step procedure works. Remember, the goal is process. Product accuracy will get better as practice improves control. All practice should be large. We are working on gross motor patterns. In the beginning, avoid using paper with lines. The first objective is letter pattern integration. A magic slate, chalkboard or magna-doodle will work well for patterning practice. After letter patterns are established it will be much easier for a child to understand the concept of place in space with lined paper. This YouTube video demonstrates the design intent of the textbook, it is also demonstrating the unique teaching method that makes it easy to teach smooth, fluent movement from the beginning or at any level with our color/rhythm models. It is that challenge, learning how to make the movements smoothly, that enhances the rate of internalization. The goal is to create patterns for the movements in the motor system. Once the "process pattern" is established, the child will be able to bring the letter from "inside the brain" and will no longer need to look at a picture of the letter in order to produce the image.
Encyclopædia Britannica, Inc.The Grand Canyon lies in the southwestern portion of the Colorado Plateau, which occupies a large area of the southwestern United States and consists essentially of horizontal layered rocks and lava flows. The broad, intricately sculptured chasm of the canyon contains between its outer walls a multitude of imposing peaks, buttes, gorges, and ravines. It ranges in width from about 175 yards (160 metres) to 18 miles (29 km) and extends in a winding course from the mouth of the Paria River, near Lees Ferry and the northern boundary of Arizona with Utah, to Grand Wash Cliffs, near the Nevada state line, a distance of about 277 miles (446 km); the first portion of the canyon—from Lees Ferry to the confluence with the Little Colorado River—is called Marble Canyon. The Grand Canyon also includes many tributary side canyons and surrounding plateaus. © Index OpenThe greatest depths of the Grand Canyon lie more than a mile (some 6,000 feet [1,800 metres]) below its rim. The deepest and most spectacularly beautiful section, 56 miles (90 km) long, is within the central part of Grand Canyon National Park, which encompasses the river’s length from Lake Powell (formed by Glen Canyon Dam in 1963) to Lake Mead (formed by Hoover Dam in 1936). The North Rim, at approximately 8,200 feet (2,500 metres) above sea level, is some 1,200 feet (365 metres) higher than the South Rim. In its general colour, the Grand Canyon is red, but each stratum or group of strata has a distinctive hue—buff and gray, delicate green and pink, or, in its depths, brown, slate-gray, and violet. Although its awesome grandeur and beauty are the major attractions of the Grand Canyon, perhaps its most vital and valuable aspect lies in the time scale of Earth history that is revealed in the exposed rocks of the canyon walls. No other place on Earth compares to the Grand Canyon for its extensive and profound record of geologic events. The canyon’s record, however, is far from continuous and complete. There are immense time gaps; many millions of years are unaccounted for, owing to gaps in the strata that resulted either from vast quantities of materials being removed by erosion or because there was little or no deposition of materials. Thus, rock formations of considerably different ages are separated by only a thin distinct surface that reveals the vast unconformity in time. © 1997; AISA, Archivo Iconográfico, Barcelona, EspañaEncyclopædia Britannica, Inc.Briefly summarized, the geologic history of the canyon strata is as follows. The crystallized, twisted, and contorted unstratified rocks of the inner gorge at the bottom of the canyon are Archean granite and schist more than 2.5 billion years old. Overlying those very ancient rocks is a layer of Proterozoic limestones, sandstones, and shales that are more than 540 million years old. On top of them are Paleozoic rock strata composed of more limestones, freshwater shales, and cemented sandstones that form much of the canyon’s walls and represent a depositional period stretching over 300 million years. Overlying those rocks in the ordinary geologic record should be a thick sequence of Mesozoic rocks (about 250 to 65 million years old), but rocks dating from the Mesozoic Era in the Grand Canyon have been entirely eroded away. Mesozoic rocks are found nonetheless in nearby southern Utah, where they form precipitous butte remnants and vermilion, white, and pink cliff terraces. Of relatively recent origin are overlying sheets of black lava and volcanic cones that occur a few miles southeast of the canyon and in the western Grand Canyon proper, some estimated to have been active within the past 1,000 years. (See also Grand Canyon Series.) David Muench—Stone/Getty ImagesThe cutting of the mile-deep Grand Canyon by the Colorado River is an event of relatively recent geologic history that began not more than six million years ago, when the river began following its present course. The Colorado River’s rapid velocity and large volume and the great amounts of mud, sand, and gravel it carries swiftly downstream account for the incredible cutting capacity of the river. Before Glen Canyon Dam was built, the sediments carried by the Colorado River were measured at an average of 500,000 tons per day. Conditions favourable to vigorous erosion were brought about by the uplift of the region, which steepened the river’s path and allowed deep entrenchment. The depth of the Grand Canyon is the result of the cutting action of the river, but its great width is explained by rain, wind, temperature, and chemical erosion, helped by the rapid wear of soft rocks, all of which steadily widened the canyon. An experiment was conducted in March 2008, in which water equivalent to about 40 percent of the river’s original flow was released from Glen Canyon Dam for a period of 60 hours to measure the erosion and deposition of sediments along the river. Researchers monitoring the experiment noted additional sand deposition at numerous locations along the river following the release. The most significant aspect of the environment that is responsible for the canyon is frequently overlooked or not recognized. Were it not for the semiarid climate in the surrounding area, there would be no Grand Canyon. Slope wash from rainfall would have removed the canyon walls, the stair-step topography would long ago have been excavated, the distinctive sculpturing and the multicoloured rock structures could not exist, the Painted Desert southeast of the canyon along the Little Colorado River would be gone, and the picturesque Monument Valley to the northeast near the Utah state line would have only a few rounded hillocks. © 1997; AISA, Archivo Iconográfico, Barcelona, EspañaTerrestrial plant and animal fossils are not abundant in the Grand Canyon’s sedimentary rocks because of the age of the rocks. Fossils are mostly of primitive algae and such marine species as mollusks, corals, trilobites, and other invertebrates. Plant life is also varied. In the bottom of the canyon, where temperatures in the summer can reach a high of 120 °F (49 °C), are willows and cottonwoods, which require abundant water during the growing season. Drought-resistant plants include tamarisks, yuccas, agaves, and numerous species of cactus. Efforts have been made to eradicate stands of the invasive tamarisk. On the canyon rims, north and south, there is a wide assortment of plant life. Typical of the South Rim, which receives about 15 inches (380 mm) of precipitation annually, is a well-developed ponderosa pine forest, with scattered stands of piñon pine and juniper. Bush vegetation consists mainly of scrub oak, mountain mahogany, and large sagebrush. On the North Rim, which receives 26 inches (660 mm) of precipitation annually, are magnificent forest communities of ponderosa pine, white and Douglas fir, blue spruce, and aspen. Under less optimum conditions the plant life reverts to the desert varieties. John Cancalosi/AlamyAnimal life in the Grand Canyon area today, however, is varied and abundant. Common mammals are the many varieties of squirrels, coyotes, foxes, deer, badgers, bobcats, rabbits, chipmunks, and kangaroo rats. In addition, the canyon region is home to a great many bird species, including raptors such as bald eagles and peregrine falcons and the rare California condor; fish species include trout and (in the Little Colorado River) the rare humpback chub (Gila cypha). James Randklev—The Image Bank/Getty ImagesThe Newberry Library, Gift of Edward E. Ayer (A Britannica Publishing Partner)Many pueblo and cliff-dweller ruins, with accompanying artifacts, indicate prehistoric occupation. The first sighting of the Grand Canyon by a European is credited to the Francisco Coronado expedition of 1540 and subsequent discovery to two Spanish priests, Francisco Domínguez and Silvestre Vélez de Escalante, in 1776. In the early 1800s trappers examined it, and sundry expeditions sent by the U.S. government to explore and map the West began to record information about the canyon. The first known descent of the river by boat through the canyon was in 1869, during an expedition to the area led by geologist and ethnographer John Wesley Powell. During the 1870s Powell and others conducted subsequent expeditions to the region, and extensive reports on the geography, geology, botany, and ethnology of the area were published. A portion of the canyon area was set aside as Grand Canyon Forest Reserve by Pres. Benjamin Harrison in 1893, and it was redesignated a game preserve (1903) and national monument (1908) by Pres. Theodore Roosevelt before the U.S. Congress officially established Grand Canyon National Park in 1919. The park’s area was greatly enlarged in 1975 by the addition of adjoining federal and other lands. In 1979 the park was designated a UNESCO World Heritage site. It is an immensely popular tourist destination, with several million visitors per year. Three Indian reservations (Navajo, Havasupai, and Hualapai) adjoin the Grand Canyon. Kaibab National Forest surrounds the main portion of the national park to the north and south, and Grand Canyon–Parashant National Monument (designated 2000) is north of the western portion of the park, extending westward to the Nevada border. Other public lands near the canyon include Pipe Spring, Rainbow Bridge, and Grand Staircase–Escalante national monuments; Zion National Park; and Glen Canyon and Lake Mead national recreation areas.
This strategically located fort was designed and built by a Japanese general, Kiyomasa Kato, in 1597 during the Hideyoshi Invasion. About 16,000 Japanese soldiers were called out to built it in about forty days out of stones carried from Ulsan p and P`y ngyang fortress. A main fortress (45 meters above the sea) is located in the south of the top (50 meters above the sea) of the mountain, the second fortress (35 meters above the sea) in the lower north of the main fortress, and the third fortress(25 meters above the sea) further down to the west and north of the second. The total fortress's wall is 1300 meters long and 10∼15 meters high. This fortress is double structured by installing a wooden fence (2400 meters) outside of the fortress. The allied army of Korea and Ming China attacked over two times(the first period ; from December 23, 1597 till January 4, 1598 and the second period ; from September 21, till September 25, 1598), but, they failed in taking away it. Afterward, the Japanese escaped to Japan after setting the fort on fire on November 18, 1598 (the 31st year of S njo's reign) following an order to retreat after the commander Toyotomi Hideyoshis's death.
Published by the American Geological Institute and Trends in the Geosciences At the close of the last Ice Age, a glacier retreated north toward what is now Lake Superior, carving out a lower basin paradise for a spruce forest. The trees flourished in the fluvial deposits for over a hundred years — while the frozen wall of death stalked slowly back. The Younger Dryas cooling event brought the glacier south again, initiating the so-called Marquette re-advance, but it stopped a few kilometers short of grinding down the forest. Instead of creating spruce-splinters, a rapid warming of the climate preserved the trees intact. The melting glacier deluged the drainage channels and riverbeds with water, sand and gravel deposits. First the trees drowned as water submerged their trunks, perhaps from a nearby flooded lake, and then, like a turned hourglass, the sand and gravel deposits quickly and carefully enveloped the entire \|About 10,000 years later, a sand mining operation uncovered the ancient branches, still soaked from being buried below the “This was a very unique find,” says Dave Reed of Michigan Technological University’s School of Forestry and Wood Products, one of 10 on a team of scientists from Michigan Tech, Harvard, Duke University and Iowa State University to study what they call the Gribben Forest. “It was buried very gently, with everything still in place,” he says. The needles on the forest floor and the moss were all still there.” Discovered in Marquette County in Michigan’s Upper Peninsula, the forest is revealing a remarkable story from the early Holocene and the end of the last Ice Age. Paleoecologists have used glacier trodden logs and wood as indicators of past climates to help make inferences for the future, but never before has an entire forest been preserved in such a pristine condition. “This leads credence to the whole line of investigation,” says Kurt Pregitzer, also of Michigan Tech and lead author of the study on the forest published in the February Journal of Ecology. Saturated with water, the buried trees turned a greenish hue, but did not rot. Michigan Technological University. The study concluded that the processes responsible for forest population and growth rates for today’s advancing tree lines are analogous to those that occurred in the Gribben Forest. The uneven distribution of the forest with sites for seeds to land, grow and germinate showed that tree migration was a patchy process. Competition was equally as strong, as pollen found on the forest floor belonged to regional taxa, but spruce dominated. Today, forests grow in northern Ontario that are similar in size and age to Michigan’s ancient forests. “It’s reassuring to find that ecological processes have transcended time,” Pregitzer says. The scientists uncovered more than 200 trees of the pure-white spruce forest. The trees mostly ranged in age from 40 to 120 years, and the oldest was 145. Using two fallen logs and comparing them to modern spruce trees, the scientists measured the height of the forest to reach about nine meters (27 feet). Chainsaws tore through 140 trees preserved in the Gribben Forest. Michigan Technological University. In the fall of 1994, the tops of tree trunks caught the attention of the Cleveland Cliffs Iron Company. They had uncovered parts of the Gribben Forest before, in the 1970s, but this time the forest proved far more extensive. To mine the sand, the crew had drained a pit below the water table, about seven meters (20 feet) from the surface, and accidentally uncovered parts of the forest. Researchers managed to collect wood samples before the mining company finished for the season and reflooded the site. The National Science Foundation helped the scientists by providing funding for exploration. Radiocarbon dates showed the forest died 9,928 years (plus or minus 133 years) before present. In the spring of 1995, the mining company again drained the pit and helped the scientists collect samples by pumping the water below the water table to the level of the forest floor. “Everybody we could pull out of the lab we had help with the project,” Pregitzer says. Then the dikes gave way, flooding the remaining trees and allowing the mining company to continue its excavation. Except for what is now frozen forest samples stored at the university, everything from the site is gone, Pregitzer says. “It was an unusual set of circumstances.” Because the forest remained below the water table, the anoxic environment preserved the dead trees. The circumstances of their death and preservation indicate a low energy, rapid burial. After the trees drowned the needles fell off, but the tiny branches, bark and buds stayed on — meaning the forest was buried under sand and more water within a year after the trees died. Additional research of the tree rings is now offering the scientists further puzzles to pursue. Preliminary evidence does not indicate the dramatic shifts in climate at the time. “There are no indications of any unusual stress or changes in climate in the decades before the trees were buried,” Reed says.
A Separate Peace Examine and extend meaning of literary work as having significant Consider contributions of plot, character, setting, conflict, and point of view when construction meaning of text. Explain how common and universal experience serve aw the source of literary themes which cross time and culture. Record, document, and organize information. What is the influence of history and culture on personal decision making as reflected in the literature of the era? What is the influence of history and culture on a specific literary piece – A What is the true meaning of disappointment? Do you lose a part of your individuality to be a part of a group: When you envy a friend, who is hurt more, the envier or the envied? What is the risk of taking responsibility for your own actions? How can a guilty conscience effect your daily life? What do you risk in being a loyal friend? The influence of World War II The culture of Private schools The economy of the 1940’s The personal background of the author The influence of peer pressure Trait Standard of Excellence Identify history and culture as an influence Significant and reliable details to defend in literature position. Cited reliable sources for all Essential question defended reliably Presented clear statement and used research project to effectively support position Relationship to personal experience Clearly and effectively demonstrates the relationship of the influence of elements of the literature to personal experience Polish Carefully and artfully presented in an mature manner with high quality Timeline of Activities Journal – Ongoing Research topics – November 29 – December 16 Decorate room with 1940’s memorabilia, such as magazines, pictures, music, and WWII Eisenhower uniform. Invite a guidance counselor to journal discussions Align journal entries to assist with personal relationship to individual students’ experience with the author’s experiences. Provide research time/place/materials Invite a guest who participated in similar experiences to the characters in the story, such as participation in WWII or private school. Tour of a private, residential school
3 interactive worksheets and 2 games/center activities for each letter of the alphabet - Help your students master uppercase and lowercase letter recognition with this fun practice packet! Students will practice letter recognition with 3 fun worksheets for each letter and 2 fun center activities. The details for the 3 worksheet pages are: 1. Ladybug Letters-Students help the lowercase ladybugs "fly" to the matching uppercase letter. 2. Candy Colors-Students color the uppercase candies one color and the lowercase candies another color. 3. Dot Marker Letters-Students identify both the uppercase and lowercase given letters and use dot markers to color them. The details for the 2 center activities are: 1. Puzzle Match-Students are given puzzle pieces with each letter in uppercase and lowercase forms. They will then go through all of the pieces and match the correct uppercase letter to the correct lowercase letter. 2. Clip Cards-There are two sets for this center. Students are given clip cards with a large uppercase letter and three possible lowercase letters or a large lowercase letter and three possible uppercase letters. They will then use a clothespin to clip the correct matching letter.
What the Mining, Construction and Excavation World Is Doing to Better the Environment With respect to greenhouse gases, carbon dioxide (40 billion tons in 2014 alone) is the pollutant we produce the most of each year. That sum was a 0.7 percent increase from 2013. Yet in 2015, there was no increase in the amount of carbon dioxide released into the air and only a small rise of 0.2 percent in 2016. Some scientists are beginning to wonder if a global effort to reduce greenhouse gases is having an effect: “The amount of CO2 we put into the atmosphere from burning fossil fuels, gas flaring, and cement production has held steady for three years in a row, neither increasing nor decreasing significantly.” The increase may be shrinking, but the sum total of CO2 we put into the air annually — from a variety of sources — is still extraordinary. While diesel is a better fuel for efficiency and overall cleanliness, its biggest downfall is CO2 emissions. A sum of 440 million metric tons of CO2 is released into the air by diesel (distillate) fuel engines each year. Diesel More Efficient and Cleaner than Gasoline with One Exception: CO2 Upon combustion, diesel fuel releases 98 percent less carbon monoxide than gasoline engines without a catalytic converter, 97 percent less hydrocarbon, 69 percent less oxides of nitrogen and 15 percent less carbon dioxide. For comparison, even gasoline cars with a catalytic converter produce 40 percent more carbon monoxide and 16 percent more hydrocarbons than diesel. Diesel is 15 percent more efficient as a fuel and about 20 percent more efficient than gasoline engines. However, diesel produces about three pounds more carbon dioxide into the atmosphere than does the combustion of gasoline. Climate Change: CO2 and Greenhouse Effect While other pollutants are more toxic than CO2, few others contribute as greatly to the greenhouse effect. Unlike CO2, which doesn’t condense with water, pollutants that do condense cannot contribute as significantly to the greenhouse effect, since water molecules in the air carry these gases back to Earth. According to NASA, “a study led by GISS co-author Gavin Schmidt that has been accepted for publication in the Journal of Geophysical Research shows that carbon dioxide accounts for about 20 percent of the greenhouse effect.” Diesel is a critical fuel with advantages over almost all other fossil and biomass fuels. It is clean, very clean, but it can be made remarkably clean with a fuel catalyst. A Rentar Fuel Catalyst outperforms other pre-combustion catalysts, reducing CO2 emissions by 40 percent. Heavy-equipment industries cannot justify the loss of power associated with other fossil fuels, alternative fuel sources, and electric motors. And, the fact is, it’s not necessary. By knocking 40 percent off the CO2 emissions, the carbon dioxide emissions from heavy equipment will be a drop in the bucket compared to things like electricity production; on-road, gasoline-powered vehicles and — ironically — natural sources.
This is our last assignment. Please work through these exercises and we will review in class. See you at four. 1) There and their are known as_____________________________. 2) And or but are ____________________________. And what do they do_____________________________________________________________. 3) Be, am, are, and, is are_____________________________________________. 4) You put a period at the end of a sentence. True or false. 5) Me is a pronoun. True or false. 6) Adjectives describe nouns. True or false. 7) You can start a sentence with a conjunction? True or false Name five pronouns? What do they do? 9) Name four adjectives? 10) Write another way to say:David’s dog got away. 11) Write another way to say: Elizabeth is small. 12) Write another way to say: You don’t like Darla’s cooking. 13) In four sentences, describe the weather outside. 14) In four sentences, tell me about our weekend. 15) In four sentences, describe what your favorite thing is to eat.
Analog to Digital Converter (Redirected from ADC) Resolution (AKA bits) The resolution of an ADC, measured in bits, determines how small a change the ADC can detect. If your microcontroller runs at 5V, and has a 10-bit ADC, it will read 0 at 0 volts, and 1023 at 5V. (1023 because 2^10(bits) = 1024, and 0 is a valid choice, so 0-1023.) Note that a digital device can only read whole numbers, so if a reading falls between 255 and 256, it will be rounded to the nearest integer value. So if your connected analog sensor outputs 2.5V, the ADC will see 511 (512 - 1). It seems, then, that 10 bits would sense very small changes, down to 0.005 V. However, if the analog sensor connected to the ADC only output between 2.5 and 3 V depending on what it sensed, then even though a 10-bit ADC can sense 1024 states, it could under these circumstances only report 102 different states. If the sensor in question was a digital compass, you could only see changes greater than 3.6 degrees — not very good at all. In this case, a higher-bit ADC would be hugely beneficial. A 12-bit ADC (4096 states) on the same setup would sense changes as small as 0.88 degrees. However, if you replaced that digital compass with one that output between 0-5V, for 0-360 degrees, and used the smaller 10-bit ADC, you could sense changes as small as 0.35 degrees. So the rule of thumb for using an ADC is that if you want the most out of it, try to use sensors that output the largest voltage range. If you are limited by the sensor, but need to sense smaller changes, you need a higher-bit ADC. An analog-to-digital converter is a device that takes an analog signal and converts it to a digital one. Typical A/D converters have 8 or 10 bits of resolution, meaning that they are able to distinguish between 2^8 (~256), or 2^10 (~1024) different voltages over the range of the A/D converter. For example, on an analog signal being received by a 10 bit A/D converter that reads between +5 volts and 0 volts, the relationship will be as follows: \|Input Voltage\|\|Digital Output Value\| \|< 0 Volts\|\|0\| \|> 5 Volts\|\|1023\| Note that for this example, the digital value for the 10 bit A/D converter never reaches 1024 (2^10 = 1024), this is because we started counting at 0. This page is an Article on bildr. Articles are pages that define or explain a concept, method, or generic item.
Fly wing with different focal planes using Zeta 3D optical profilometer Focus detection works much like how we see the world. The instrument determines what is in focus and what is out of focus by looking for sharp contrasts. Areas with sharp contrast are deemed in focus, and by knowing this focal length of the optics you can determine the distance. This generally works by scanning the optics in the Z direction and using the camera in order to create a three dimensional volume of data. After the data is acquired, the parts that are out of focus are cut out and you are left with a representation of the surface of the sample. This technique can also be performed by using a zoom microscope with a variable focus to create the volume. This technique is generally simpler with less resolution at a lower cost. By using regular microscope objectives and precision Z movements, the X, Y and Z resolution can be greatly enhanced; the resolution is still lower than confocal or interferometry instruments.
While the anuria definition means no urine, the medical condition of this symptom refers to a dangerously low urine output. Complete failure to produce urine is actually kidney failure. Our normal urine output ranges from one to two liters per day. For proper body functioning, we must get rid of 300 to 500 milliliters of waste and fluid each day. Anuria occurs with less than 50 milliliters of output per day, but is considered to be present when output reaches under 100 milliliters. What Causes Anuria? Known as the advanced or late stage of a kidney problem, anuria occurs when the urine flow has dipped between 50 to 100 milliliters over a 24-hour period. It follows the serious stage called oliguria, when urine output is below 500 milligrams a day. There are three main causes leading to anuria. This stage refers to a problem indirectly affecting the kidneys. These problems can include issues with the blood vessels in the kidneys. Under prerenal, we find three major causes with varying symptoms. Hypovolemia is the decrease of blood plasma. This happens with diarrhea, vomiting, hemorrhage, burns, pulmonary edema, consuming diuretics, and fluid loss due to surgery or drainage. Low systemic vascular resistance refers to the expansion of blood vessels. This can be caused by a state of shock, sepsis, a reaction to certain prescription drugs, and the workings of antihypertensive drugs. Heart failure occurs when the heart cannot pump blood as efficiently as it should. This can be a result of arrhythmia, heart attack, cardiomyopathy, cardiac tamponade, and a decrease in blood output by the heart. Other causes of the prerenal stage include diabetes, anaphylaxis, pancreatitis, and compression of the renal vein or the inferior vena cava. This stage may also be reached due to health conditions such as congenital heart disease, respiratory distress syndrome, perinatal asphyxia and indomethacin, or by using certain medications during pregnancy. This anuria cause refers to issues of the kidneys due to diseases, and the effects of long-term use of some medications. At this stage, we see a decrease in urine output. This can be initiated by autoimmune, systemic and vascular diseases, congenital kidney issues, or by having a family history of renal problems. It can also be seen with endogenous toxins and with the use of nephrotoxic drugs. Cases have also been seen with hematuria, muscle trauma, and glomerulonephritis. Postrenal causes occur with the outflow of urine from the kidneys. Obstruction causes in the kidneys can include a mass, calculi, lower urinary tract issues, benign prostatic hypertrophy, retroperitoneal fibrosis, or a mechanical problem if using a catheter. Anuria Symptoms and Complications As anuria is a symptom in itself, it can be accompanied by other symptoms occurring beforehand. These can include a change in the flow of urine, such as dribbling and a lower urine output. You can check your urine output by tracking it over a 24-hour period. This is done by comparing the amount of fluid intake with the amount of urine output. Physical symptoms associated with anuria may be nausea, vomiting, diarrhea, decrease in appetite, and muscle weakness. Renal surgery patients and people with recurring urinary tract infections, enlarged prostate glands, and congenital kidney disease can experience complications of anuria. Anuria Treatment Tips Medical treatment of anuria consists of recognizing the underlying cause, as well as any medical history relating to the anuria. For example, if the cause is an obstruction of the urine flow, you may need to undergo a surgical procedure to remove or repair the obstruction. Any low urine output is a cause for concern, and should be addressed by a professional health care provider. Based on the cause, there are some holistic medicine professionals that use herbs to treat symptoms and prevent further complications. These treatments can include the following: - Cucumber: Combine one teaspoon of ground cucumber seeds and one glass of coconut water. - Avocado: Boil 500 milligrams of water and add 200 grams of avocado leaves. Leave it overnight. Drink one cup of mixture daily. - Cabbage: Use daily in broths, soups, or salads. - Java Tea: Boil one cup of water with five grams of java tea leaves twice daily. - Chayote: Boil one cup of water with the leaves or seeds of chayote for a drink to be taken twice daily. - Carrot: Mix four grams of carrot seed with one glass of warm water for a drink to be taken three times a day. - Land Caltrops: Boil one plant and add one teaspoon of honey to every 20 milligrams of mixture for a daily drink. Anuria is a serious symptom of kidney problems, and needs to be addressed before further complications such as bladder inflammation and kidney failure takes hold. There are several causes of anuria that offer their own symptoms to watch for. Anuria can be treated and even prevented in many cases. If you are suffering from any of the previously discussed symptoms or diseases, it is imperative you monitor your urine output closely to avoid anuria.
Cenozoic EraArticle Free Pass Cenozoic life was strikingly different from that of the Mesozoic. The great diversity that characterizes modern-day flora is attributed to the explosive expansion and adaptive radiation of the angiosperms that began during the Late Cretaceous. As climatic differentiation increased over the course of the Cenozoic, flora became more and more provincial. Deciduous angiosperms, for instance, came to predominate in colder regions, whereas evergreen varieties prevailed in the subtropics and tropics. Fauna also underwent dramatic changes during the Cenozoic. As was discussed in earlier sections, the end of the Cretaceous brought the eradication of dinosaurs on land and of large swimming reptiles (e.g., ichthyosaurs, mosasaurs, and plesiosaurs) in marine environments. Nektonic ammonites, squidlike belemnites, sessile reef-building mollusks known as rudistids, and most microscopic plankton also died out at this time. The Cenozoic witnessed a rapid diversification of life-forms in the ecological niches left vacant by this great terminal Cretaceous extinction. In particular, mammals, which had existed for more than 100 million years before the advent of the Cenozoic Era, experienced substantial evolutionary radiation. Marsupials developed a diverse array of adaptive types in Australia and South America free from the predations of carnivorous placentals. The placental mammals, which today make up more than 95 percent of known mammals, radiated at a rapid rate. Ungulates (or hoofed mammals) with clawed feet evolved during the Paleocene (65.5 to about 55.8 million years ago). This epoch saw the development and proliferation of the earliest perissodactyls (odd-toed ungulates, such as horses, tapirs, rhinoceroses, and two extinct groups, the chalicotheres and titanotheres) and artiodactyls (even-toed ungulates, including pigs, peccaries, hippopotamuses, camels, llamas, chevrotains, deer, giraffes, sheep, goats, musk-oxen, antelopes, and cattle). During the later Cenozoic, perissodactyl diversity declined markedly, but artiodactyls continued to diversify. Elephants, which evolved in the late Eocene about 40 million years ago, spread throughout much of the world and underwent tremendous diversification at this time. Many placental forms of giant size, such as the sabre-toothed cat, giant ground sloths, and woolly mammoths, inhabited the forests and the plains in the Pliocene (5.3 to 1.8 million years ago). It was also about this time that the first hominids appeared. Early modern humans, however, did not emerge until the Pleistocene. Among marine life-forms, mollusks (primarily pelecypods and gastropods) became highly diversified, as did reef-building corals characteristic of the tropical belt. Planktonic foraminiferans underwent two major radiations—the first in the Paleocene and the second in the Miocene—punctuated by a long (15–20-million-year) mid-Cenozoic reduction in diversity related in all likelihood to global cooling. Cenozoic life was affected significantly by a major extinction event that occurred between 10,000 and 8,000 years ago. This event, which involved the sudden disappearance of many Ice Age mammals, has been attributed to either of two factors: climatic change following the melting of the most recent Pleistocene glaciers or overkill by Paleolithic hunters. The latter is regarded by many as the more likely cause, as the rapidly improved technology of Paleolithic humans permitted more efficient hunting. Do you know anything more about this topic that you’d like to share?
The collapse of Saint-Domingue, the richest colony in the entire world, into the Republic of Haiti, which is the poorest country in the Western hemisphere, can be summed up in this one brief post. Inspired by the French Revolution, there was a successful slave insurrection in Saint-Domingue in 1791. The National Assembly abolished slavery throughout the French Empire in 1794. In 1804, Haiti won its independence and the remaining Whites (with a few exceptions, mostly Germans and Poles, who became honorary blacks) were exterminated. In 1805, Haiti was officially proclaimed a black country. Whites were banned from citizenship and owning property under the Haitian constitution. The ban on White ownership of property in Haiti would remain in effect until 1918 when a constitution was approved under the American occupation. Laurent DuBois gives us a feel of Saint-Domingue on the eve of its destruction by a Negro Revolt on pages 24-28 of his book Avengers of the New World: The Story of the Haitian Revolution: “The northern plain traversed by streams from the mountains, was an ideal place for sugar plantations. In 1789 the Northern Province, which included Le Cap, the plain, and the surrounding mountains, contained 288 sugar plantations, most of these producing refined sugar; 443 indigo plantations; and more than 2,000 coffee plantations. The population included 16,000 whites and at least 160,000 slaves. . . . In 1789, there were 314 sugar plantations in the Western Province, more than in the north, although many of them were smaller and produced unrefined sugar. Indigo cultivatations was much more important in this region than in the north, involving over 1,800 plantations. There were more than 500 cotton plantations and more than 800 coffee plantations. . . . On the long peninsula to the south and west was the Southern Province. . . It was the least developed of the colony, with only 191 sugar plantations, most of them making unprocessed sugar, and approximately 300 coffee plantations and 900 indigo plantations. It had the smallest population of the three.” Saint-Domingue under French colonialism in 1789 could have been described as “The Arsenal of Agriculture.” Such was its importance to the French economy. The Haitian Revolution was by far the most radical of all the egalitarian revolutions in what has been labelled the “Age of Revolution” by historians. This is the key to understanding why Haiti is so much worse off than all of its black neighbors in the Caribbean. Black freedom was taken to its greatest extreme there. (1) Haiti was the first successful post-colonial revolution. Now in the 208th year of free society, Haiti is the oldest black republic in the world. By contrast, Jamaica didn’t become independent until 1962. Barbados didn’t become independent until 1967. Both Jamaica and Barbados remain part of the British Commonwealth. (2) Haiti won its independence in a violent slave insurrection, a three way war between Britain, France, and Spain for control of Saint-Domingue, and finally by defeating the Leclerc expedition. In contrast, slavery was peacefully abolished in the British West Indies in 1834. In Saint-Domingue, the sugar plantations went up in a giant blaze in the Northern Province that could be seen for miles offshore, whereas plantation agriculture continued in Barbados and Jamaica. (3) When the Haitian Revolution began in 1791, over half the slaves there had been born in Africa. Most had been born in the Kongo Kingdom in West Central Africa. The Haitians remained more culturally African than any of their neighbors. In contrast, the British abolished the slave trade in 1804. When slavery was abolished in the British West Indies in 1834, the vast majority of slaves there were creoles. In Dixie and Barbados, the legacy of slavery was much greater, and consequently, the former slaves were more civilized and better prepared for freedom. (4) The fact that Haiti won outright independence from France cannot be stressed enough. Nowhere else was abolition followed by black independence, black self government, the extermination of Whites, the black rejection of plantation agriculture, the black destruction of white supremacy, property redistribution to blacks, etc. In Guadeloupe and Martinique, slavery was restored, white supremacy and colonialism were restored, and both islands are still to this day overseas departments of France. Like Barbados, the legacy of slavery, colonialism, and white supremacy is much greater in Guadeloupe and Martinique, and consequently, both islands tower over Haiti and sub-Saharan African countries in the U.N. Development Index. The same is true of Puerto Rico which is a welfare dependency of the United States. (5) In Dixie, the Emancipation Proclamation and the 13th Amendment abolished slavery. African-Americans ceased to be slaves, but like those in Jamaica, they didn’t become property owners, and after Reconstruction, white supremacy was restored. In a sense, the blacks remained in a state of benign serfdom in the South, socially, politically, and economically, they were not as “free” as the Whites. In Haiti, the plantations were either annihilated in the Haitian Revolution, or fell into the hands of the new incompetent black political class (this would happen again with the “Big Vegetables” in Mobutu’s Congo). The Whites were exterminated in Haiti and were banned from citizenship and owning property. Over the course of thirty years, a “counter-plantation system” developed in which a black peasantry refused to work on the plantations, and gradually wrestled control of the land away from the big landowners and reverted to subsistence agriculture. The dream of “40 acres and a mule” was realized in Haiti in what was called the lakou system which was a kind of collective village agriculture. The retreat from slave labor and plantation based commercial agriculture to free labor and subsistence based agriculture in the early nineteenth century is what brought about the crushing poverty that is so commonly associated with Haiti. These export numbers come from “The Beauties of Negro Rule: The Present and Past of Hayti” which was published in the June 1855 edition of DeBow’s Review. They illustrate the decline of plantation agriculture and the rise of the “counter-plantation system” in Haiti: In 1789, Saint-Domingue under the French colonial government exported 93,573,300 pounds of raw sugar, 46,516,531 pounds of white sugar, 76,835,219 pounds of coffee, 76,835,219 pounds of cotton, and 7,004,278 pounds of indigo. In 1801, Saint-Domingue under Touissant L’Ouverture (who forced the “cultivators” to remain on the plantations) exported 8,016,540 pounds of raw sugar, 18,517,381 pounds of white sugar, 29,510,450 pounds of coffee, and 2,170,440 pounds of cotton. Indigo and tobacco had ceased to be grown. In 1819, Haiti under King Henri Christophe (the “counter-plantation system” emerges under Dessalines, Christophe, and Boyer) exported 1,200,000 pounds of raw sugar, 15,500,000 pounds of coffee, and 2,000,000 pounds of cotton. In 1849, Haiti under Emperor Soulouque exported 80,608,343 pounds of coffee and 664,516 pounds of cotton. From 1789 until 1849, there was a 100 percent collapse in raw sugar and white sugar production in Haiti, a 100 percent collapse in tobacco and indigo, and a 99 percent collapse in cotton production. It seems strange that coffee production alone in Haiti would recover to 1789 levels, but this one export can be easily explained as one of the legacies of slavery: “Nowhere the coffee tree could better thrive than here, as it especially likes mountainous soil. But the indolence of the negroes has brought the formerly so splendid plantations to decay. They now gather the coffee only from the grown-wild trees. The cultivation of the sugar cane has entirely disappeared, and the island that once supplied one-half of Europe with sugar, now receives its own wants from Jamaica and the United States. To the banana tree and the half-wild hogs owes the “free negro” almost alone that he by his laziness has not yet died of starvation on this truly paradisaical island.” In “Hayti and the Haytians,” we are told that the quality of wild Haytian coffee harvested by free negroes was vastly inferior to the product that had been cultivated under White administration on the French plantations: “Agriculture in Hayti has recently been so much neglected, and the products so badly prepared, that Haytian coffee is in little repute in European markets, from the careless and slovenly way in which it is gathered; good and bad berries are mixed up with stones and dirt, to add to the weight. When properly cleaned and separated, the coffee of this island has been considered superior to any in the West Indies. This same negligence has applied of late years to her cotton, cocoa, and longwood.” Even before Haiti won its independence in 1804, when the island was still a colony administered by Touissant L’Ouverature, we learn on pages 229-230 of Avengers of the New World that the Visible Black Hand of Economics was already busily resculpting the fertile Northern Province of Haiti in the image of the now dominant Black Undertow: “Much had changed in Saint-Domingue since the days of slavery. Whites and blacks, former master and former slaves, had redefined their relationships and their place in the social order. The landscape was a patchwork shaped by intersecting histories of insurrection, war, and negotiation. A former plantation owner traveling through the colony in 1799 came across some functioning sugar plantations and a few thriving coffee plantations. But he focused on the many ruined properties, where “bushes and trees” had entirely “replaced the houses” and old cane fields were covered with grass and ivy. His biggest shock came when, from the peak of a mountain where once “we stopped in ecstasy to see the plain of Le Cap in all its splendour,” he could see only “ruins and bushes” where sugarcane had once covered the land. On the plains of Le Cap and throughout the colony, a new kind of life was taking root, one based on independence and subsistence, one that for many ex-slaves embodied true freedom. In and around the ruins of old plantations, men and women cultivated small plots of land, growing crops for their families and to sell at the markets.” In the year 2012, a White man born in the 1920s might have the same experience as the Le Cap plantation owner in 1799 by driving through the Metro Detroit area, which is now in the 39th year of free society since the election of Coleman Young as mayor in 1973. As in Haiti, he would focus on the abandoned factories and businesses, and all the deserted neighborhoods and other commercial properties that are being reclaimed by bushes and trees. He might find “a new kind of life” taking root in Detroit as the predominantly black residents hunt and feast on raccoon, buy candy crack pipes at gas stations, and shoot nine month old babies with AK-47 assault rifles. The failure of the American political class to admit the tragic truth that black people lacked the capacity to maintain civilization in Haiti (more like forgotten, as this was known at the State Department in 1918) is why we having to learn the same lesson all over again in Detroit.
Use shift registers when you want to pass values from previous iterations through a loop to the next iteration. A shift register appears as a pair of terminals, shown as follows, directly opposite each other on the vertical sides of the loop border. The terminal on the right side of the loop contains an up arrow and stores data on the completion of an iteration. LabVIEW transfers the data stored in the right terminal of the shift register to the left terminal. The loop then uses the data from the left terminal as the initial values for the next iteration. This process continues until all iterations of the loop execute. After the loop executes, the terminal on the right side of the loop returns the last value stored in the shift register. A shift register transfers any data type and automatically changes to the data type of the first object wired to the shift register. The data you wire to the terminals of each shift register must be the same type. You can add more than one shift register to a loop. If you have multiple operations that use previous iteration values within a loop, use multiple shift registers to store the data values from those different processes in the structure, as shown in the following block diagram. In the previous block diagram, the upper right shift register terminal transfers 2, the sum of 0 and 2 in the first iteration, to the upper left terminal as the initial value for the second iteration of the addition operation. The lower right terminal transfers 2, the product of 1 and 2 in the first iteration, to the lower left terminal as the initial value for the second iteration of the multiplication operation. The second iteration adds 2 and 2 and transfers the outcome, 4, to the upper left terminal for the third iteration. The second iteration also multiplies 2 and 4 and transfers the outcome, 8, to the lower left terminal for the third iteration. After ten iterations, the upper right terminal transfers the final outcome of the addition operation to the upper indicator and the lower right terminal transfers the final outcome of the multiplication operation to the lower indicator.
The Reading Like a Historian curriculum engages students in historical inquiry. Each lesson revolves around a central historical question and features a set of primary documents designed for groups of students with a range of reading skills. This curriculum teaches students how to investigate historical questions by employing reading strategies such as sourcing, contextualizing, corroborating, and close reading. Instead of memorizing historical facts, students evaluate the trustworthiness of multiple perspectives on historical issues and learn to make historical claims backed by documentary evidence. To learn more about how to use Reading Like a Historian lessons, watch these videos about how teachers use these materials in their classrooms.
Presentation on theme: "Bell Ringer What are the Iliad and the Odyssey about?"— Presentation transcript: 1 Bell Ringer What are the Iliad and the Odyssey about? What does the following quote mean? And do you agree with it?“The Unexamined Life is not worth living.” – Socrates 2 ObjectiveI can recognize the impact of the Greek philosophers and historians on world history.6.6.2 Recognize the impact of individuals on world history 3 PhilosophersSocrates, Plato, and Aristotle were three important philosophers from Athens.Greek philosophers taught their students to think rationally, or using reason. This contrasted with the popular Greek mythology about gods. 5 Vocabulary Philosophy- “love of wisdom” Philosopher- Greek thinkers who believed the human mind could understand everythingSophists- professional teachers in Ancient GreeceSocratic Method- Way of teaching developed by Socrates that used question-and-answer format to force students to use reason to see things for themselves 6 The SophistsThe Sophists were the first professional teachers of GreeceTraveled from city to cityBelieved in no absolute right or wrongBelieved people should use knowledge to improveDeveloped the art of public speaking and debate 7 Socrates Athenian sculptor and philosopher Left no writings behind Believed in an absolute truth and that all knowledge was within each person (different from the sophists)Taught using the socratic method- students had to answer questions and reason to find answers 8 SocratesAthenian government saw the Socratic method was a threat to powerDid not like/trust the idea of open debateGovernment charged him with teaching youths to rebel against the state and follow reason 9 Socrates Trial“Socrates is accused of refusing to recognize the gods recognized by the state, and of introducing new divinities (reason). He is also accused of corrupting the youth.” Should Socrates be punished for his actions? 10 Socrates Sentence“Socrates is guilty of refusing to recognize the gods recognized by the state, and of introducing new divinities. He is also guilty of corrupting the youth. The penalty demanded is death.” 11 Should Socrates escape? Crito, Socrates friend, tells Socrates that he can pay a bribe to get him out of jail and escape death.Imagine that you are Socrates. Would you escape, or would you stay and prepare for death? Why? 12 PlatoPlatoStudent of Socrates. Wrote much of what we know about SocratesRejected the idea of democracy. Believed that Philosopher-kings should rule with logic and wisdomDescribes his ideal government in his book RepublicDivided government into 3 groups- philosopher-kings, warriors, and the rest of the peopleIntroduced the idea that government should be just and fair which we still believe todayEstablished the Academy 13 Aristotle Student of plato Opened the Lyceum Taught the idea of the golden meanIdea that a person should do nothing to excessDon’t eat too much or eat too little made advancements in scienceStudied and wrote about government in his book PoltiicsThought the best kind of government was a mix between a few people running it and the whole peopleFounders of US Constitution tried to create this balance 14 Read Crito by PlatoWhat do you notice about the way Socrates builds his arguments?How does Socrates make his point? 15 AnalysisWhat motivates Crito in his attempt to help Socrates escape from prison? Why would we say that he has "good" intentions?What motivates Socrates in his decision to accept his punishment? What concept of the "good" does he seem to hold? How does this concept compare to Crito's sense of what is good and right?Who do you agree with? Who has stronger arguments? 16 Imagine…You are Crito, trying to convince your friend Socrates to escape from prison. Come up with arguments to convince him to escape. 17 ReasonNow you try…Pretend you are Socrates. Ask questions to examine your partner’s arguments. 18 Exit TicketTrue or false and explain: Aristotle’s main idea was the golden mean which means excess it a good thing.True or false: Plato believed that the right form of government was a democracyTrue or false: Socrates used questioning in the Socratic methods to help his students learn to reason
Recent news reports have described a dramatic decrease in California’s population of Western Monarch butterflies. Thirty years ago, over 4.5 million of these beautiful flying insects migrated annually from Mexico to overwinter on the Pacific Coast, with huge, fascinating clusters at famous sites, including Pacific Grove and Natural Bridges State Beach. Their numbers have declined over the years: this year the count was under 30,000 individuals, 0.6% of the population’s historic size. Researchers had established 30,000 as the “quasi extinction threshold,” so coming under this threshold suggests that this species (Danaus plexippus plexippus) is approaching extinction. Another, larger number of monarchs migrate from Mexico to the northern plains of the United States, so extinction is not imminent, but that population also has been shrinking in recent decades. The causes of the decline in the monarch population begin with the loss of suitable habitat, defined as areas that include both milkweeds (Asclepias sp.) that Monarch caterpillars depend upon, and pollen plants that provide nutrition for the adults. Milkweed plants are too often deleted from the environment by agricultural pesticides, particularly glysophate (RoundUp), which is used to kill unwanted plants among commercial crops. Other factors include pesticide use, climate change, and logging and development projects that degrade overwintering sites. Gardeners can help rescue monarch butterflies back from the threat of extinction by growing milkweed plants in their gardens, with preference for locally native species of this plant. Fifteen species of milkweed are native to California. Nearby sources of seeds for native species include Pacific Coast Seed, in Livermore; Seedhunt, in Freedom; and S&S Seeds, in Carpenteria. For information on growing milkweed, download “Native Milkweed in California: Planting and Establishment.” A related project for gardeners is to include pollen plants for the adult monarch butterflies. Useful advice for such a project is available in “California Coast: Monarch Nectar Plants,” available here. Both of these publications are free downloads from the Xerces Society for Invertebrate Conservation. The Xerces Society has also produced a five-step call to action for recovering the western monarch population. This plan emphasizes protection of overwintering and breeding habitats, protection from pesticides, and continuing research on western monarch recovery. In addition to actions in their own gardens, people concerned with threats to the monarch population could support large-scale initiatives that respond to the Society’s call to action. Protecting the Western Monarch Butterfly from extinction has at least three broad objectives. One is for us all to enjoy the phenomenon of these beautiful creatures flitting about in our gardens. A second objective, oriented to the ecosystem, is to maintain these butterflies as food sources for birds, which we also appreciate and enjoy. Thirdly, Karen Oberhauser, director of The Monarch Butterfly Lab at the University of Minneapolis, advises that monarch butterflies are valuable subjects for ongoing studies of migration, species interaction, insect population dynamics, and insect reproduction. We can strive to keep monarch butterflies in our environment, but we should also acknowledge the larger picture of the extinction of species. Before humans spread across the globe, species extinctions occurred for various reasons at a very slow rate. Human activity has increased the average rate of extinction by somewhere between 100 to 1,000 times the previous historical rate., and is accelerating Today, according to Edward O. Wilson, distinguished American biologist, the science community estimates that Planet Earth has about 10 million living species, one of which is human people (Homo sapiens). About 20 percent of these species are known, and 80 percent are undiscovered. If the extinction of species by human activity continues to accelerate, E.O. Wilson says, we could eliminate more than half of all species by the end of this century. We can slow this trend a little by working as individuals. Consider adding California native milkweed and pollen plants to your garden this year, to sustain the monarch butterflies.
Gingivitis is the medical term for early gum disease, or periodontal disease. In general, gum disease can be caused by long-term exposure to plaque, the sticky but colorless film on teeth that forms after eating or sleeping. Gum disease originates in the gums, where infections form from harmful bacteria and other materials left behind from eating. Early warning signs include chronic bad breath, tender or painful swollen gums and minor bleeding after brushing or flossing. In many cases, however, gingivitis can go unnoticed. The infections can eventually cause the gums to separate from the teeth, creating even greater opportunities for infection and decay. Although gum disease is the major cause of tooth loss in adults, in many cases it is avoidable. If gingivitis goes untreated, more serious problems such as abscesses, bone loss or periodontitis can occur. Periodontitis is treated in a number of ways. One method, called root planing, involved cleaning and scraping below the gum line to smooth the roots. If effective, this procedure helps the gums reattach themselves to the tooth structure. However, not all instances of scaling and root planing successfully reattach the tooth to the gums. Additional measures may be needed if the periodontal pockets persist after scaling and root planing Pregnancy has also been known to cause a form of gingivitis. This has been linked to hormonal changes in the woman's body that promote plaque production.
How are mountains formed ? In this fact file we will answer this question and find out how all mountains are formed. Mountains are formed in many different ways ( block , dome , fold and plateaus)and all of theses mountain types are all over the world. Block mountains are formed when 2 tectonic plates collide or pull apart from each other . The ground on either side of the block mountain is pulled down while the block mountain is pulled upwards and this is due to the tectonic plates. An amazing example of a block mountain is Mount Everest , which is in the Himalayas mountain range. When dome mountains are formed, molten rock , which comes from deep inside of Earth , pushes against the Earths crust and results in a dome shaped mountain . Although dome mountains have molten rock (lava) , it does not break the surface (crust) of the Earth and if it did then the mountain would not be a dome mountain , it would be a volcano. A fold mountain , which is the most common type of mountain , is formed when tectonic plates (over millions of years ) push forward and begin to fold , making a fold mountain. Eventually after enough time it can form a mountain range of fold mountains. The Himalayas mountain range is a folded mountain range , which began to form when the Indian and Asian plates collided . A plateau mountain is formed in a similar way to the dome mountain and it is formed when magma fails to break the crust of the Earth ( if it did it would turn into a volcano ) . Plateaus mountains can occur in every continent of the world , which makes it take up 1/3 of our land. An example of a plateaus mountain is the Yellowstone Plateaus ( it is located in the United States ) . VF: Well done providing so many examples of your mountain types. You have included fronted adverbials, a variety of punctuation and topic specific vocabulary. MR
The scale used or key of a piece is represented on the music staff by an icon called the key signature. Western music uses primarily major or minor scales, which are seven notes. If you play all the white keys on the piano starting with C you can hear what a major scale sounds like. But if you were to play only the black keys on the piano, you would hear a different scale — the pentatonic scale — a scale or mode that uses only five notes per octave. If you start on D# on the piano you would have a pentatonic minor scale. If you would begin on F# you would have a pentatonic major scale. These are two of the more common pentatonic scales. (See illustration) Many composers have used the pentatonic scale especially in folk traditions — from Celtic music to gospel music to ancient Greek music and from Afro-Caribbean traditions to Chinese music and jazz traditions. The Javanese Gamelan and the Ethiopian Krar — a five or six-stringed Bowl-shaped lyre from Eritrea and Ethiopia — are tuned in the pentatonic scale. Impressionistic composers such as Debussy, used the scale liberally as did Chopin famously in his Étude in G flat major Opus 10 No. 5 the Black Keys Étude and Ravel used it in Ma Mère L’Oye (Mother Goose Suite.) Perhaps the scale sounded a little exotic to them! Chopin Etude Opus 10 no. 5 “Black Keys” Ma Mère L’Oye The Hungarian people are very proud of their historic folk music. Composers Zoltán Kodály and Béla Bartók traveled to the remote villages of Hungary to catalog, research and write down the folk music of the Hungarians, which had been preserved solely as an oral tradition. They found that Hungarian “peasant music” often does not use a regular meter and uses the pentatonic scale with a strong rhythmic steadiness or tempo giusto! These features differentiate “Hungarian peasant music” from that of any other nations. Bartók studied over 300 melodies. The more modern tunes used for dancing, featured pentatonic turns with frequent leaps of the interval, or distance between two notes, of a fourth (or four notes). Hungarian gypsy music is quite distinctive as well. It has an exotic romantic flavor. The gypsy music uses the so called Hungarian minor scale and although this scale does use seven notes, the spaces between the notes are unique as are the instruments used including the Cimbalom — a type of hammered dulcimer composed of a large, trapezoidal box with metal strings stretched across its top. Two long sticks with a spoon shaped ends hammer the strings — quite wonderful! The Zoltán Kodály-based method, originally developed in Hungary but now used worldwide, is designed to develop musical skills and to teach musical concepts to very young children through singing. Kodály used the pentatonic scale because of its simplicity, and it plays a significant role in this method. “Teach music and singing at school in such a way that it is not a torture but a joy for the pupil; instill a thirst for finer music in him, a thirst which will last for a lifetime.” Kodály advocated continuously and believed strongly that a person cannot be complete without music. Music, he said, serves to develop a person on all levels – emotionally, spiritually and intellectually. Kodály also believed that all people, everyone, has musical aptitude and that music education should begin as early as possible in a person’s life — at home and then later at school. Every child can learn music and has a right to an education in music. Kodály believed that musical instruction should reflect the way that children learn naturally. Through singing games, fun and play, the child discovers the musical elements and has the opportunity to enter the world of music. The voice of course, is the most accessible of all instruments and can lead to a well-tuned ear. Singing is a great start to learn music, especially via the folk music traditions of each country and the easiest entry is the pentatonic scale! Scales don’t have to be boring. Many cultures have used the pentatonic scale in their indigenous music. That’s how we Hungarians became related to the Chinese. We are all related through our music. Ethiopian Oldies – Krar Song Kodály flash mob Richter plays Bartok 15 Hungarian Peasant Songs (2/2) Bobby McFerrin Demonstrates the Power of the Pentatonic Scale
In recent decades, asthma has become a major public health problem. The exponential increase in asthma cases in industrialized countries over the past 50 years is due to major changes in our environment. Among these environmental factors: excessive hygiene, ambient air pollution or respiratory viral infections... Until now, the mechanism by which these particular environments induce the development of asthma was unknown. In a study published in Nature Immunology, Professors Thomas Marichal (FRS-FNRS Research Associate, Welbio and ERC investigator) and Fabrice Bureau (Welbio investigator) and their teams from GIGA ULiège identified a totally unexpected actor who represents a common denominator in different pro-allergic environments: particular neutrophils are recruited into the lung and are responsible for allergic sensitization and asthma development. This discovery allows new therapeutic options to be considered in the prevention and treatment of allergic asthma. Coraline Radermecker, the first author of the study, first developed three models of asthma in mice induced by pro-allergic environments: excess hygiene, exposure to ozone (an air pollutant) and infection with the influenza virus. In all three models, only mice exposed to pro-allergic environments and then exposed to mites, major allergens in humans, developed symptoms of allergic asthma. She and her colleagues then observed the recruitment of specific innate immune cells, neutrophils, only in the lungs of mice exposed to pro-allergic environments. These neutrophils, once in the lung, release their DNA, causing inflammation that is conducive to the development of an allergic response such as asthma. Surprisingly, when mice exposed to pro-allergic environments are treated with compounds that prevent the recruitment of these neutrophils or the release of their DNA, mice are protected from disease development. A recent study identified this same type of particular neutrophils in the blood of a population of American farmers, the Hutterites, exposed to a very high rate of hygiene and having a very high prevalence of allergic asthma. The latter suggests that these neutrophils are also present in humans and may be involved in the development of asthma in humans. In addition, a molecule already used in human medicine to treat cystic fibrosis, pulmozyme, could be used to destroy DNA released by neutrophils and prevent the development of asthma in people exposed to high-risk environments. Radermecker, C. et al. (2019) Locally instructed CXCR4hi neutrophils trigger environment-driven allergic asthma through the release of neutrophil extracellular traps. Nature Immunology. doi.org/10.1038/s41590-019-0496-9.
The lazily winding spiral arms of the spectacular galaxy NGC 976 fill the frame of this image from the NASAEstablished in 1958, the National Aeronautics and Space Administration (NASA) is an independent agency of the United States Federal Government that succeeded the National Advisory Committee for Aeronautics (NACA). It is responsible for the civilian space program, as well as aeronautics and aerospace research. It’s vision is “To discover and expand knowledge for the benefit of humanity.””>NASA/ESA Hubble Space TelescopeThe Hubble Space Telescope (often referred to as Hubble or HST) is one of NASA’s Great Observatories and was launched into low Earth orbit in 1990. It is one of the largest and most versatile space telescopes in use and features a 2.4-meter mirror and four main instruments that observe in the ultraviolet, visible, and near-infrared regions of the electromagnetic spectrum. It was named after astronomer Edwin Hubble.”>Hubble Space Telescope. This spiral galaxy lies around 150 million light-years from the Milky WayThe Milky Way is the galaxy that contains the Earth, and is named for its appearance from Earth. It is a barred spiral galaxy that contains an estimated 100-400 billion stars and has a diameter between 150,000 and 200,000 light-years.”>Milky Way in the constellation Aries. Despite its tranquil appearance, NGC 976 has played host to one of the most violent astronomical phenomena known — a supernova explosion. These cataclysmicly violent events take place at the end of the lives of massive stars, and can outshine entire galaxies for a short period. While supernovae mark the deaths of massive stars, they are also responsible for the creation of heavy elements that are incorporated into later generations of stars and planets. Supernovae are also a useful aid for astronomers who measure the distances to faraway galaxies. The amount of energy thrown out into space by supernova explosions is very uniform, allowing astronomers to estimate their distances from how bright they appear to be when viewed from Earth. This image — which was created using data from Hubble’s Wide Field Camera 3 — comes from a large collection of Hubble observations of nearby galaxies which host supernovae as well as a pulsating class of stars known as Cepheid variables. Both Cepheids and supernovae are used to measure astronomical distances, and galaxies containing both objects provide useful natural laboratories where the two methods can be calibrated against one another.
This guide presents a variety of artworks, from the 17th century to the present, that highlight the presence and experiences of Black communities across the Atlantic world. Use the collections in the virtual gallery below to engage your students in conversation about the many narratives of everyday life, enslavement, and resistance that have been told through art. Lesson plans are provided to extend these conversations and help students consider the many and continuing legacies of the transatlantic slave trade. This Teacher’s Guide offers a collection of lessons and resources for K-12 social studies, literature, and arts classrooms that center around the experiences, achievements, and perspectives of Asian Americans and Pacific Islanders across U.S. history. Archival visits, whether in person or online, are great additions to any curriculum in the humanities. Primary sources can be the cornerstone of lessons or activities involving any aspect of history, ancient or modern. This Teachers Guide is designed to help educators plan, execute, and follow up on an encounter with sources housed in a variety of institutions, from libraries and museums to historical societies and state archives to make learning come to life and teach students the value of preservation and conservation in the humanities. The National Endowment for the Humanities has compiled a collection of digital resources for K-12 and higher education instructors who teach in an online setting. The resources included in this Teacher's Guide range from videos and podcasts to digitized primary sources and interactive activities and games that have received funding from the NEH, as well as resources for online instruction. Our Teacher's Guide offers a collection of lessons and resources for K-12 social studies, literature, and arts classrooms that center around the achievements, perspectives, and experiences of African Americans across U.S. history. This Teacher's Guide will introduce you to the cultures and explore the histories of some groups within the over 5 million people who identify as American Indian in the United States, with resources designed for integration across humanities curricula and classrooms throughout the school year. Since 1988, the U.S. Government has set aside the period from September 15 to October 15 as National Hispanic Heritage Month to honor the many contributions Hispanic Americans have made and continue to make to the United States of America. Our Teacher's Guide brings together resources created during NEH Summer Seminars and Institutes, lesson plans for K-12 classrooms, and think pieces on events and experiences across Hispanic history and heritage. Poet. Orator. Actress. Activist. Writer. Singer. Phenomenal Woman. These and many more superlatives are used to describe the incomparable Maya Angelou. Gone too soon in 2014 at the age of 86, Dr. Angelou’s legacy will live on through the words she used to eloquently, powerfully, and honestly express emotions, capture experiences, and spread hope.
« PreviousContinue » Cane-sugar, unlike glucose, is decomposed by strong sulphuric acid, with copious formation of carbonaceous matter. It is not turned brown when treated with alkalis, and is insoluble in cold absolute alcohol. It dissolves in one-third of its weight of water at mean temperature, and in all proportions in boiling water. From a solution containing 5 parts of sugar to i part of water, threefifths of the sugar crystallizes on cooling in four or six sided rhomboidal prisms. ESTIMATION OF SUGAR. Cane-sugar does not precipitate the suboxide of copper from alkaline solutions of cupric tartrate, but it is very readily converted by boiling with dilute acid into invert-sugar, which does possess that property. Advantage is taken of this in what is generally called “Fehling's test.” A solution is made by dissolving 86 grams of tartaric acid in crystals with 104 grams of caustic soda. To this is added 29 grams of sulphate of copper dissolved in water. The bulk is then made up by additional water to 1 litre. This is Fehling's solution, and in its application for the estimation of sugar it may be used either volumetrically” or “gravimetrically:" in either case it is necessary in the first place to have a standard. In the volumetric process, which is the easier, '625 gram of pure cane-sugar is for this purpose boiled for ten minutes with about 4 ounces of water acidulated with 5 drops of concentrated sulphuric acid. The solution is then cooled, neutralised with solution of caustic soda, and made up to a bulk of 250 cubic centimetres. Twenty-five cubic centimetres of the copper solution are then heated in a white glass flask to the boiling point, and the sugar solution is run into it from a burette, care being taken not to add more than will reduce the whole of the copper. It will generally be found that 40 cubic centimetres of the sugar solution, which correspond to 'I gram cane-sugar, or 105 gram glucose, will be required to reduce the copper or decolourise 25 cubic centimetres of copper solution. If more or less than 40 cubic centimetres are required, a corresponding difference will have to be made in the quantities of cane-sugar and glucose represented respectively. This result is applied in the examination of saccharine substances or solutions in the following way : If a known weight-say 8 grams—of a liquid which contains glucose and cane-sugar be taken and made up to 250 cubic centimetres, and if it be found that 45 cubic centimetres of this diluted solution are required to reduce the copper in 25 cubic centimetres of Fehling's solution, the percentage of glucose is thus found : 50 X 100 X '1 6.94 per cent., the cane-sugar equivalent, or 7.30 per cent. glucose. It is then necessary to make a second experiment to find the total amount of sugar present. A less weight than beforesay 4 grams—is taken and boiled for four minutes with about 4 ounces of water and 5 cubic centimetres of normal sulphuric acid to invert the cane-sugar. It is then neutralised with soda and made up as before to 250 cubic centimetres at 60° F. (15.5°C.), and if it be then found that 50 cubic centimetres of this solution are necessary to reduce the copper in 25 cubic centimetres of Fehling's solution, the total sugar in the liquid, calculated as cane-sugar, is as follows: 250 X 100 X 'I = 12-5; and 12-5-6-94 = 5'56, the percentage of cane-sugar present. In the gravimetric method, the standard is the quantity of cuprous oxide precipitated by a given quantity of sugar-solution. The cuprous oxide being either ignited with a little nitric acid, and weighed as cupric oxide, or, as recommended by Pavey, the suboxide of copper is dissolved, and the copper precipitated from it by electrolysis and weighed. Fehling's test, although fairly accurate, where the percentage exceeds o‘5 per cent., is not well adapted for cases in which it falls below that quantity. Knapp's method, based upon the decomposition of an alkaline solution of cyanide of mercury, has been suggested where the quantity of sugar is very small. The standard liquid is prepared by dissolving 10 grams pure dry mercuric cyanide in water, adding 100 cubic centimetres of sodium hydrate solutionspecific gravity l'145, and diluting to 1,000 cubic centimetres. Ten cubic centimetres of this solution are equal to 25 milligrams of glucose. To apply the test, 10 cubic centimetres of the solution, diluted with from 20 to 30 cubic centimetres of water, are heated to the boiling point. The sugar solution is run in from a burette until the whole of the mercury is precipitated. When the precipitate has settled, a drop of the supernatant liquid, which has a more or less yellow tint, is transferred by means of a capillary tube to a thin pure white Swedish filter-paper. This paper is held, first over a bottle containing strong hydrochloric acid, and then over a saturated sulphuretted hydrogen solution. The slightest trace of mercury is shown by the production of a light brown or yellow stain. It is well to place a drop of the original liquid beside that which has been subjected to the action of hydrochloric acid and sulphuretted hydrogen for comparison. Cane-sugar, when exposed to the action of yeast, is rapidly changed, first into invert - sugar, and then into alcohol and carbonic dioxide, the following being the reactions : A process based upon the quantity of alcohol produced by fermentation from a given quantity of sugar has been long in use for estimating the percentage of sugar in substances to which, owing either to their colour or to the fact that they contain matter other than sugar capable of reducing salts of copper, Fehling's method cannot be applied. In determining the amount of sugar by the fermentation process, the quantity taken, in order to insure complete fermentation, should not exceed 100 grains. Assuming that 100 grains of the sample to be analysed, when dissolved in about a quart of water and fermented with 200 grains of pressed yeast, yield a distillate of 1,000 fluid grains of a density of 9903 at 60° F. (15.5° C.), and that 200 grains of yeast similarly fermented yield a distillate of the same volume, having a density of 9983, the following calculations will give the percentage of canesugar or glucose present. By Gilpin's tables it will be found that mixtures of alcohol and water of a density of 990'3 and 998-3 contain respectively 5'52 grains and •88 grain by weight of absolute alcohol in each 100 fluid grains, and therefore 55'2 and 8.8 grains respectively will be contained in each distillate. Deducting the latter from the former, there temain 46'4 grains of absolute alcohol as having been produced from the sugar. By the equations given above 342 parts by weight of cane-sugar, or 360 parts of glucose, are seen to be necessary to produce thecretically 184 parts of absolute alcohol; hence 464 x 342 46°4 x 360 Should the rectifying power of the distilling apparatus used not be sufficient to insure the collection of the whole of the alcohol in the first distillate of 1,000 fluid grains, a second similar bulk must be distilled over, and the amount of alcohol found added to that obtained in the first distillate. As small quantities of glycerin and succinic acid are formed during fermentation, the amount of sugar, calculated from the alcohol produced, is invariably less than the true quantity, even under the most favourable conditions. It is sometimes desirable, therefore, in practice, to make experiments with pure cane-sugar, and to use the highest alcoholic result obtained as a factor for calculating the amount of sugar contained in saccharine substances submitted to the fermentation test. Another process is to estimate the sugar from the loss of carbonic dioxide in the course of fermentation. Its application requires very great care in manipulation, and it is not likely to be resorted to, except in cases in which the other processes are inapplicable. The most ready method of estimating the percentage of pure cane-sugar in raw sugars, whether derived from beet or cane, is by the polariscope. The principle of this instrument is that a plane polarised ray of light may always be considered as made up of two circularly polarised rays, and if these pass through a medium, such as sugar, tartaric acid, etc., which retards the one more than the other, the plane of polarisation of their resultant when they leave the medium will in general not be the same as that of the incident ray—or, in other words, it will have been caused to rotate through a certain angle, sometimes to the right and sometimes to the left. This rotation varies in the different descriptions of sugar, both in regard to the angle and the direction. If a tube I decimetre long be filled with a solution of pure cane-sugar, containing i gram in every cubic centimetre of fluid, it will rotate the plane of polarisation 73•8 degrees to the right, and this is called the specific rotatory power of pure cane-sugar. Rotation is in proportion to the length of the tube, and the mass of substance possessing the rotatory power, water being quite neutral. It follows, therefore, that if we take a solution, containing a decigram of pure cane-sugar in every cubic centimetre of fluid, the tube being the same length as before, we obtain a rotation of 7380. If we then take an impure cane-sugar, and make a solution such that it shall contain I decigram in every cubic centimetre of liquid, fill a tube, 1 decimetre in length, with such solution, and find the rotation to be 6'3°, we should, supposing no invert-sugar to be present, find the percentage of sugar by the following proportion : as 7*38 : 6'3 :: 100: x. The rule for finding the specific rotation from the observed rotation is: Divide the observed rotation by the length of the tube, multiplied by the weight of sugar in each cubic centimetre of liquid, I gram being the unit of weight, and I decimetre the unit of length. Thus if a solution, containing o'150 gram of sugar in
The recent COVID-19 outbreak has been the main reason behind several temporary school closures around the world. This has made the idea of continuing to pursue educational activities during this time a challenging proposition. The current lockdowns implemented in different countries has forced schoolteachers who wish to complete their current teaching periods to transition immediately to the online classroom. Many schools have already started online classes in the wake of the crisis caused by the global COVID-19 crises. Accessing and managing online teaching resources can be a bit difficult for educators or pupils accustomed to a conventional classroom. A couple of our authors reached out to us and asked if Bentham Science had a solution for their book, Computer Based Projects for a Chemistry Curriculum – which is a great resource for school and college students and teachers interesting in using computers to illustrate fundamental concepts in chemistry. And we have responded. Starting today up to June 30, Bentham Science Publishers is making the eBook free to download. This means high school teachers and students anywhere in the world can access the content benefit from the projects presented in the book. Computer Based Projects for a Chemistry Curriculum, authored by Thomas Manning and Aurora Grumatges, presents 24 chapters each giving information about activities employing applications such as MS excel (spreadsheets) and Spartan (computational modeling). Each project is explained in a simple, easy-to-understand manner. The content within this book is suitable as a guide for both teachers and students and each chapter is supplemented with practice guidelines and exercises. The book contents can be accessed here. We hope that students around the world can benefit from the interesting and informative variety of projects presented in the book, while also allowing educators working in schools to continue their teaching activities throughout the academic year amidst the current pandemic crisis. Stay safe, and happy chemistry learning. Please visit the book page here: http://bit.ly/39uzhTW
Students enter words in the gaps, based on the context within a given article, individually or collaboratively. This activity helps improve your vocabulary and sentence structure and your communication skills. Type: Individual or Group collaboration Instructions: Click on the gap and type in a word. Click on the light bulb icon (if any) for help. The words of sentences are scrambled and students must sort them into their original order. This activity helps you study sentence structure by providing you with genuine text and allowing you to select suitable materials to practice on. Instructions: Put the bold words in the correct order by drag-drop them into the correct position. This activity is for image collections only. A randomly chosen image is shown to one player (called the "describer"), while the other player (the "guesser") must identify it by asking questions. This activity helps improve your communication skills and vocabulary. Type: Collaboration in pairs Instructions: The "describer" sees a single image and describes it to their partner through the chat box. Based on what their partner says, the "guesser" selects one of the images by double-clicking. Both score a point if it is the correct image. If a timer is shown, the "guesser" must make their choice before time runs out. Students collaborate to predict words they think will occur in a given text, This activity provides a learning environment in which you help each other by sharing information and exchanging ideas. Type: Group collaboration Instructions: In the text box, type your guesses of what words you think might be in the article. Use the title and/or image to help you think of words.
Crohn’s Disease is a chronic, recurrent inflammatory disease of the intestinal tract. The intestinal tract has four major parts: the esophagus, or food tube; the stomach, where food is churned and broken down; the long small bowel, where nutrients, calories, minerals, and vitamins are absorbed; and the colon, where water is absorbed, stool is stored and a good many health benefits occur. The two primary sites for Crohn’s disease are the last portion of the small bowel (the ileum) and the colon (Crohn’s colitis). The condition appears to start when the colon’s normal bacteria stick to the colon’s lining more readily. Normally, the colon easily fights this off as its immune defenses are so robust and strong. In Crohn’s Disease, however, this does not occur. Small nests of inflammation occur, persist and smolder. The inflammation becomes worse and spreads. The lining of the bowel can then become ulcerated and the bowel wall thickened. Eventually, the bowel may become narrowed or obstructed, at which time surgery would be needed. What Causes Crohn’s Disease? For the most part, Crohn’s Disease is a disorder of young people, even children. There is now evidence of a genetic link as Crohn’s frequently shows up in families and certain ethnic groups. For instance, the disease is more common in Jewish people and less so in African Americans. As noted, there is evidence that the normal healthy bacteria that grow in the lower gut may, in some manner, act to promote inflammation. The body’s immune system, which protects it against many different infections, is a factor. So, a number of clear factors are necessary for Crohn’s Disease to occur. There is a genetic link that predisposes some people. The colon’s normal bacteria are necessary. The colon’s own immune system fails to control the local infection. There are still a number of unknowns about the cause of the disease; however, research is rapidly increasing our knowledge. Fortunately, a great deal is known and there are now a variety of effective treatments available. Crohn’s Disease Symptoms The symptoms of Crohn’s disease depend on where in the intestinal tract the disorder appears. When the ileum (ileitis) is involved, recurrent pain may be experienced in the right lower abdomen. At times, the pain mimics acute appendicitis. When the colon is the site, diarrhea (sometimes bloody) may occur, along with fever and weight loss. Crohn’s disease often affects the anal area where there may be a draining sinus tract called a fistula. When the disease is active, fatigue and lethargy appear. In children and adolescents, there may be difficulty gaining or maintaining weight. Nutrition and vitamin deficiencies often occur. So, the main symptoms of Crohn’s Disease may be: Recurrent, lower abdominal discomfort Failure to gain weight normally, especially in the young Chronic fatigue and lethargy Bowel urgency and/or diarrhea, sometimes bloody Sores or drainage in the anal area The diagnosis often begins with a physician’s suspicion that Crohn’s Disease may be present. The patient’s medical history and physical exam are always helpful. Certain blood and stool tests are necessary. X-rays of the small intestine and colon are usually required. In addition, a colonoscopy exam of the entire colon is often the best way of diagnosing the problem. A colonoscopy exam is where the colon is cleaned out and then visually inspected with a lighted endoscope. Biopsy specimens can be obtained. Colonoscopy is usually the definitive exam in making a diagnosis. Course and Complications The disorder often remains quiet and easily controlled for long periods of time. Most people with Crohn’s disease continue to pursue their goals in life, go to school, marry, raise a family, exercise and work with few limitations or inconveniences. Some problems, outside the bowel, can occur. Arthritis, eye disorders, skin problems, and in rare instances, chronic liver conditions may develop. If the disease occurs around the anal canal, open painful sores called fissures can develop. A fistula can also form. A fistula is a tiny channel that burrows from the rectum to the skin around the anus. Infrequently, fistulas can track into the urinary bladder, the vagina or even another part of the intestine. In addition, when inflammation persists in the ileum or colon, narrowing and partial obstruction may occur. Surgery is usually required to treat this problem. When Crohn’s disease has been present for many years, there is an increased risk of cancer. A major problem that may occur very early in the disease is the loss of calcium in the bones. This occurs without any symptoms. At this stage, it is called osteopenia. Later, when it progresses, it is called osteoporosis. Since Crohn’s Disease, for the most part, is a disease of young people, this bone loss can occur at a very early age. This is why most Crohn’s patients need to take extra calcium and vitamin D in their diet and with supplements. In addition, they should get a bone scan (densitometry) to detect early loss of bone. A simple x-ray will not detect early bone loss. Effective medical and surgical treatment is available for Crohn’s disease. It is particularly important to maintain good nutrition with a balanced diet, get adequate exercise, consume adequate vitamins and minerals, especially calcium and vitamin D, and keep a positive, upbeat attitude. See Crohn’s Dietary Therapy for details. Five types of medications are available to treat this disease. Cortisone or steroids (prednisone) – These powerful drugs can provide highly effective results. A large dose is often used initially to bring severe disease under quick control. The drug is then tapered to a low maintenance dose, perhaps taken just every other day. Hopefully, the drug may eventually be stopped altogether. Unfortunately, steroids promote calcium loss from bone. This is a major problem for Crohn’s patients. So, early detection and preventative therapy is imperative. Anti-inflammation drugs – Sulfasalazine, (Azulfidine, Dipentum, Asacol, Rowasa, Pentasa and Lialda) belong to a group of drugs called the 5-aminosalicylates. These drugs are most useful in maintaining a remission, once the disease is brought under control. They are most effective when the disease is present in the colon and less so for Crohn’s in the small bowel. Immune System Suppressors – These medications suppress the body’s immune system, which appears to be overly active and somehow aggravates the disease. The names of two of these commonly used medications are azathioprine (trade name: Imuran) and 6MP (trade name: Purinethol). These drugs are particularly useful for long-term maintenance. There are other potent immune-suppressing drugs that may be used in difficult cases. Biologics – These are newer and highly effective compounds that block certain stages of the inflammation. Infliximab (trade name: Remicade) and adalimumab (trade name: Humira) are two such medications. Antibiotics – Since there is frequently a bacterial infection along with Crohn’s disease, antibiotics are often used to treat this problem. Two that are commonly used are ciprofloxacin (trade name: Cipro) and metronidazole (trade name: Flagyl). Dietary therapy for Crohn’s patients is being increasingly recognized as a vital part of overall care. In a real sense, the patient must become an active partner in her or his care. Dietary therapy means that the patient or the caregiver of a patient understands the importance of the following in Crohn’s patients. Protein – how much and what type Carbohydrates – again, how much and what type Vitamins – especially the importance of C, D and some of the B vitamins Minerals – calcium, selenium, zinc A full outline of this information can be accessed in the Diet block below. Fiber, Prebiotics, and Probiotics Fiber in plant food is now known to be especially healthy for everyone’s general health. For Crohn’s Disease patients, fiber can be recommended when the disease is inactive, and especially when there is no narrowing of the bowel, where plant fiber could induce blockage. Soluble prebiotic fibers are a more recently discovered type of fiber, which has some real bowel benefits. Their use in Crohn’s patients is still not certain but since they are simply plant food, there are few side effects. The prebiotic fibers, inulin, and oligofructose are the names of the best-studied ones. They promote the growth of good colon bacteria which, in turn, make short chain fatty acids. These fatty acids may be a real benefit to Crohn’s patients as they seem to make bacteria less adherent to the bowel wall and are actually the fuel source for the bowels own cells. A probiotic is a good bacteria or yeast taken by mouth that, hopefully, grows in the colon and produces good results. There is some scientific evidence that probiotics may help some Crohn’s patients. In particular, the use of probiotics and prebiotics together may be appropriate for some. Again, check with your physician. Stress and Surgery Surgery is commonly needed at some time during the course of Crohn’s disease. It may involve removing a portion of diseased bowel, or simply the draining of an abscess or fistula. In all cases, the guiding principle is to perform the least amount of surgery necessary to correct the problem. Surgery does not cure Crohn’s disease. Most people with Crohn’s disease lead active lives with few restrictions. Although there is no known cure for the disorder, it can be managed with present treatments. There is increased emphasis on patients helping themselves by good dietary management, meaning adequate calories, vitamins, minerals and even prebiotic food fibers and probiotic bacteria. For a few patients, the course of the disease can be complicated, requiring extensive testing and therapy. Surgery sometimes is required. By working closely with your physician and managing your own emotional and dietary behavior, most patients will have a good long-term outcome. Visit the Crohn's and Colitis Foundation for supporting information. There is now very clear evidence that Crohns Disease always has a dysbiosis of the colonic bacteria. This means that there are more bad than good bacteria within the colon. What is not known as yet is whether this is helping to cause the Crohns problem or whether it is a result of the disease. However, what is now apparent is that making a major effort to change this bacterial makeup is a logical potential therapeutic goal. The following articles from major academic centers speak directly to this issue, mentioning prebiotics as a possible agent. New therapeutic options for inflammatory bowel disease here and here. Crohn’s Disease (CD) is a disorder of the small intestine and often the right side of the colon or large bowel. It is an inflammatory disorder in that the bacteria that normally reside in the gut are able to invade the bowel wall and cause the disease. In the past, we physicians did not think there was anything specific about the diet that needed to be avoided. We prescribed a good nutritious diet with enough protein, calories, and vitamins and that was about it. However, there has been an explosion of information and research not just about the very cause of Crohn’s Disease, but also about the diet itself – and how the foods we eat could favorably (and unfavorably) influence the disorder. The Lower Gut and the Importance of Insoluble Fiber People with a healthy bacterial mix tend to weigh less, demonstrate better immunity to disease, absorb vitamins and minerals easier (resulting in stronger bones), feel less stress and more. Up until the past 15 years, the importance of the lower gut has been downplayed in medical literature and in education in general. Training physicians relegated the gut to a minor health role and largely ignored the pounds of bacteria living in and on the human body. Only recently has medical science began carefully examining these bacteria, the roles they play in overall health and wellness, and how a nutritious diet comprised of fiber-rich foods can positively affect Crohn’s disease and other conditions. It turns out that the microbiota in the lower gut plays an enormous role in health. People with a healthy bacterial mix tend to weigh less, demonstrate better immunity to disease, absorb vitamins and minerals easier (resulting in stronger bones), feel less stress and more. Although a healthy body can result from good genes to some extent — as demonstrated below — you can positively affect your overall health and the symptoms of Crohn’s by manipulating your lower gut’s microbiota yourself. You can do this by modifying your food intake to a diet designed for Crohn’s disease. The effective Crohn’s disease diet contains a diet rich in the insoluble fibers found in foods such as chicory root, bananas, onions, garlic, Jerusalem artichoke, whole grains and more. For optimal health, eating between 25 and 35 grams of soluble and insoluble fiber every day is recommended; unfortunately, most people simply do not eat enough fiber to make a difference in their overall wellness. Why is fiber important? Fiber fertilizes the lower gut’s healthy bacteria, reduces the permeability of the bowel wall and can help with the uncomfortable symptoms of Crohn’s disease, among other things. Supplementing the Ideal Crohn’s Diet Getting enough fiber to satisfy your diet for Crohn’s doesn’t have to mean eating garlic and bananas on whole wheat bread several times per day. These foods contain the plant fibers inulin and oligofructose, which are prebiotics that has been proven to fertilize healthy lower gut bacteria. Although these fibers won’t fix Crohn’s disease completely, they can improve the strength of your bowel wall and fight the other factors that worsen disease symptoms. Adding a prebiotic fiber supplement to your diet that contains both inulin and oligofructose is an easy way to favorably adjust this bacterial mix and boost your overall wellness. Treating CD With a Specialized Crohn’s Diet The dietary treatment of CD, based on known recent and startling science and research, is now one of the most exciting new discoveries in gastroenterology. It promises to have enormous benefits to almost everyone with this disorder. Although diet modification is an exciting new frontier in the treatment of this condition, before embarking further into the diet, it is useful to know briefly about 3 important areas. Here are 3 new proven key facts about Crohn’s Disease. What Does Research Tell Us? We, physicians, take pride in using evidence collected from research to guide us in treatment. Everyone wants proven facts whenever it comes to their treatment. We are slowly getting a handle on the very basic causes of Crohn’s. We know that a genetic makeup is required. We also know that something in what we eat and/or drink is really important. The answers are not all in yet, but we now know enough that we can give some pretty good answers to the dietary questions everyone with this disorder has. A large medical study was published in the American Journal of Gastroenterology in 2011. The authors reviewed over 1000 published medical articles on this subject and found 19 that provided good enough information to reach important conclusions. Here is what they found. There was an increased risk of getting the Crohn’s Disease if a person ate: A high protein and/or meat diet A high saturated fat diet, including trans fats A high vegetable polyunsaturated fat and especially omega 6 and oil diet A low fiber diet Some of the reports looked at all animal protein that was consumed-meaning meat, poultry, fish and dairy products. Others evaluated just meat, meaning mostly beef and pork products. The consensus was that Crohn’s patients should not go overboard on animal protein, especially meat. The average daily amount of animal protein in an American diet is 75-100 grams. 50 grams is almost certainly enough. This is about the size of a deck of cards. Saturated fat is found in well-marbled meat, bacon, all processed meat including sausage, but also in whole and even 1-2% fat-reduced milk. Butter, lard, chicken skin, coconut and palm oil are other sources of saturated fats. But the information on poly-unsaturated fats was what was most disturbing. These are the fats found in fish, most vegetable oils, and nuts. They are the ones that have been shown to be so good for you in reducing cholesterol and perhaps heart disease. Nevertheless, in the Crohn’s-prone individual, they seem to act differently. This was particularly true of the omega 6 vegetable oils. They make it more likely you will get CD. The bottom line seems to be that a reduction in most fats, including the omega 6 vegetable oils, may be a smart move. Here is where the payoff might be for the Crohn’s patient. It is the soluble plant fibers that are the major fertilizers and foods for the very best colon bacteria. It is these bacteria species that are so healthy for the gut wall. They produce lots of nutrients for the health of the colon cells. They acidify the inside of the colon, a very beneficial outcome. When they are exuberantly growing, these good bacteria prevent bad bacteria that none of us want in our lower bowel. Eating a wide variety of vegetable, fruit and whole grain foods every day does the trick. There is clearly a genetic makeup for those people who get CD. Up to 100 genes have been identified that may be involved and there are likely many more. Some of them are also present in those people who have or will get ulcerative colitis. They are also present in other non-gastrointestinal disorders such as certain immune-related diseases like rheumatoid arthritis and multiple sclerosis. Research is moving very fast but as of this time, we know that genes are important. The gene is the 1st fact to remember. By this, I want to cover a very broad area, but mostly it involves the diet. When people have active CD, we know it gets better when the bowel is put at complete rest. This means hardly anything except water by mouth. There is something in foods or liquids that we take by mouth that aggravates the Crohn’s inflammatory process. When you remove these injurious factors, you get better. But we haven’t known for sure what it is that is causing the problem. Could it be a non-food item such as some environmental factor or chemical that is added to food? We don’t or, before now, didn’t know, but now we are beginning to get some pretty good ideas. The important point is that someone or multiple things that we take by mouth, most likely in the very foods we eat, are the problem. So, the 2nd fact to remember is environment or diet. Bacteria have a bad reputation because of advertising and the occasional bad bacteria that gets into the news. However, almost all bacteria are either benign or actually good for us. We simply have bacteria everywhere both inside and outside our body. For the most part, they protect us and usually provide very real health benefits. The lower part of the small intestine and particularly the colon contains an immense number of bacteria. These are the key factors for the CD patient. As noted, the bacteria within our gut are usually our friends and give us many benefits such as making vitamins and a robust immune system. In the Crohn’s person, a few of them can and, indeed, do behave differently. For reasons that are only now becoming clear, these bacteria are able to move through the protective defenses of the gut and then invade the bowel wall. If there are no bacteria within the gut, there is no Crohn’s Disease. So, the 3rd key fact to remember is bacteria. Your Gut Bacteria Factory To understand Crohn’s Disease as we physicians now do, it is important to know the basics of what is happening within our own gut bacteria factory. The gut, especially the colon, is packed with over 1000 species of bacteria and the total number of these little bugs are trillions upon trillions. For every cell in our body, there are at least 10 bacteria cells in the colon and the total number of genes of these bacteria outnumber our own gene count by over 100 times. These beneficial bacteria have been part of us for as long as living things have been on earth. As noted, we simply could not live without the benefits that these bacteria provide us. The most remarkable is that they give us a robust immune system that protects us our entire life. But here is where it gets troublesome for those with Crohn’s Disease. If the bacteria factory is so beneficial, then why is it such a problem for those with the genetic makeup for CD? The answers to that question are slowly becoming known. Along with this knowledge is the fact that our treatments for CD have improved dramatically. But, just as important, so has our understanding of what happens within our gut with certain foods. We now know that some foods can and, indeed, do make a difference in the intestinal inflammation that is the hallmark of CD. The Mucous Layer The word mucous brings up a vision of a runny nose when you have a common cold. Not very pleasant. However, mucous is a very valuable and healthy substance to have in the body. Every membrane within our body has a mucous layer overlying it, including the inside of our nose. The excess mucous that comes from a nasal cold is simply the body’s method of protecting us and helping us get rid of the cold. A better term and one that we physicians and researchers use is biofilm. The mucous layer or biofilm is a dense layer of protein-like material that adheres to the inside lining of our intestinal tract. It is the first line of defense in the gut and prevents bacteria from moving through and attacking the wall of the gut itself. In addition, we have a vigorous and robust immune system in the wall of the colon itself. The mucous layer and these immune cells together are a strong defense mechanism except for people who get Crohn’s Disease. Something happens to this mucous layer or biofilm. Under these conditions, bacteria are able to migrate through the mucous layer and cause inflammation to the underlying tissue. This is how Crohn’s begins. In no other intestinal condition that we know is the mucous layer breached like what happens in Crohn’s Disease. One final comment. Emulsifiers are a large group of additives that manufacturers put in many foods. Detergents are another group of chemicals that are extremely prevalent around the house and kitchen. Remember these 2 words-emulsifiers and detergents. I will have more to say about them and how they may disrupt the intestinal mucous layer or biofilm. There is simply an enormous amount of good information available on a low saturated fat and high fiber diet. These can be accessed at usda.gov, eatright.org, amazon.com and every bookstore. Searching Google for high-fiber and a low-fat diet can be useful. In particular look for non-commercial sources. The low saturated fat, high fiber diet recommended for coronary heart disease patients is exactly what seems to be beneficial for inflammatory bowel disease patients. The American Heart Association has cookbooks and recipes that can be ordered on their website, heart.org. Inflammation is what Crohn’s Disease is all about. The key fact is that bacteria within the gut, for reasons we now understand rather well, penetrate the protective mucous layer covering the inside of the gut. From there they invade the bowel wall and so cause Crohn’s Disease. Science now knows a lot about inflammation in the body. For the Crohn’s patient, they are worth knowing. a) Colon wall The typical Western-style, high saturated fat, high meat diet does 2 things that we know. First, it stimulates the production of excessive bile from the liver. In animals, this excess bile promotes the growth of certain bacteria in the colon which can cause a Crohn’s like inflammation in susceptible animals. This is bad enough. But the 2nd major thing that these saturated fats do is to induce a change in the makeup of the bacteria in the gut itself. Again, this leads to mild but definite inflammation in the colon wall. Just as important, the cells that line the colon weaken and allow bacterial materials to leak between the cells and accumulate in the blood. This is known as a leaky gut. People on a Western style, high-fat diet have a leaky gut. This is not desirable. b) Immune strength The major part of your immune system comes from the colon wall. This starts on the day we are born when bacteria first start to grow in the infant’s intestine. Following a diet, as outlined above enhances the strength of your immune system through your entire life. This, in turn, likely makes a positive difference in how your body responds to inflammation. c) LPS (lipo-poly-saccharide) This terrible sounding word refers to break down materials from the wall of the bacteria within the gut. When these substances slide through a leaky gut wall, as is present in CD, they then enter the blood stream. There they are called endotoxins or simply toxins. They induce inflammation throughout the body, in fat cells, in the lining of arteries (atherosclerosis), the liver and elsewhere. Nobody wants the toxins in their body, especially a Crohn’s patient. d) Omega 3 and Omega 6 oils Understanding these oils can be plain confusing. Omega 3 oils are the really desirable ones. They are protective of the heart, are present in fish, especially fatty fish and in some nuts and vegetable oils such as canola oil. Omega 3 oils decrease inflammation in the body. Omega 6 oils, on the other hand, may be bad and not so desirable, even though they are of the polyunsaturated fat type. It is the ratio or the proportion of the omega 6 to the omega 3 oils in the product that appears to be important. For instance, olive oil has a ratio of 10:1, which is borderline desirable. However, olive oil has a great deal of the very desirable mono-unsaturated fats. Canola oil, on the other hand, has a ration of omega 6 to omega 3 of about 2:1, which is very good. Canola and olive oils are likely the healthiest cooking and vegetable oils for our bodies. The bottom line for inflammation is to follow a Crohn’s diet as outlined above. This diet: Reduces the inflammation in the bowel wall Enhances the immune factors within it Reduces the inflammation that can occur within the body through a leaky gut and endotoxins Our bodies need amino acids in order to build the proteins we need to stay healthy. These amino acids come from proteins that we eat, either in animal meats or in plants such as fruits, whole grains, and vegetables. In either case, these proteins are broken down by our digestive system into amino acids, which are absorbed and then used to build our own proteins. Animal protein provides all the essential amino acids we need, whereas it is necessary to eat a variety of plant material to get the full complement of required amino acids. This is rather easily done. The bottom line is that our body doesn’t much care where the amino acids come from. They are all the same whether they come from animal or plant. However, there are other things in meat, especially the saturated fats that make a difference in what happens in the colon. Here a high animal meat diet leads to a bad balance of bacteria. This, in turn, induces inflammation and a leaky gut, which are not good for the Crohn’s patient. Reducing the meat portion of a meal to about 50 grams provides the protein we need and also shifts the bacterial balance in a favorable way. 50 grams of meat is about the size of a deck of playing cards. Every vegetable, grain or fruit has fiber in it. It is what gives the plant its specific shape. Although there are many types of fiber, there are just 2 that are important for health, insoluble fiber and soluble fiber. Insoluble fiber means that the fiber does not dissolve in water and is not fermented by the colon’s bacteria. Rather, it retains water and, in so doing, helps to promote stool softness and regularity. Wheat in all its forms is mostly insoluble fiber. Soluble fiber, on the other hand, does dissolve in water. More important than this is the fact that the bacteria within the colon ferment it. It is a fuel for their own growth. The very best of the soluble fibers are called prebiotic fibers. A prebiotic fiber is used by the very best bacteria for their own nutrition and in so doing produce measurable health benefits for the body. Our Prebiotin Prebiotic Fiber is the most researched type of prebiotic fiber. National authorities recommend the following daily intake of fiber. Men: 30 grams Women: 25 grams These numbers will vary depending on sex, weight and body size. A varied mix of fruits, whole grains and vegetables will usually provide an adequate amount of both insoluble and soluble fibers. A person with Crohn’s Disease needs to increase fiber intake gradually so as to allow the gut to become tolerant to it. If this gradual process is followed, harmless excessive gas and bloating should not be a problem. Caffeinated beverages may overly stimulate the bowel. Prebiotic soluble plant fibers are the very best. They are present in many vegetables and fruits. These plant fibers promote the growth of the best beneficial colon bacteria. When these bacteria thrive, many positive health outcomes occur, including better immunity, increased calcium and magnesium absorption, a healthier bowel wall (no leaky gut), less inflammation, reduced toxins in the blood and many others. Oligofructose and inulin are the names of the 2 best-known prebiotics with the most research behind them. These prebiotic fibers are particularly rich in wheat, rye, leeks, asparagus, chicory, Jerusalem artichokes and many other root vegetables like yams, bananas, garlic, agave, and others. Our Prebiotin supplement, taken daily, can provide the assurance that you are getting enough prebiotic. It has long been known that fruits are an exceptionally healthy food for just about everyone. What has been recently found in Crohn’s patients is that fruits are specifically protective for them. Fruits have so many vitamins, minerals, antioxidants and so much fiber that there is virtually no limit to how much can be eaten. Fruit juice, on the other hand, may cause some problems. These are often high in plain glucose and fructose which may be troublesome for some. They usually have had all the beneficial fiber removed. Some Crohn’s patients will note that their GI tract tends to act up with fruit juices. You simply have to test yourself. Vegetables are the dietary backbone for the Crohn’s person. These are the foods that have so many of the beneficial fibers, including the very best prebiotics, inulin, and oligofructose. They provide bulk for bowel regularity and are the source of fuel for the beneficial bowel bacteria. It is these good bacteria that we want to see predominate within the gut. A high fat, high meat diet will always shift the bacterial balance in the opposite way, weakening the bowel wall, allowing a leaky gut to develop and ensuring that endotoxins or toxins are absorbed into the bloodstream. A wide selection of vegetables should be eaten and prepared with condiments as desired. If oils are to be used in preparation, note that canola oil and olive oil are likely the healthiest and best, as they provide a very good ratio of the good omega 3 oil to the not-so-good omega 6 oils. It is important to discuss vitamins with the physician. For the Crohn’s patient, the following points on vitamins are worth considering. Multiple vitaminMany physicians feel that inflammatory bowel disease persons should take basic multiple vitamin preparations each day. Folic acid – This vitamin prevents birth defects so it is particularly important for the female who may become or actually is pregnant. Vitamin B12 – Some Crohn’s patients do not absorb enough B12 from the intestinal tract. The physician will want to check this level in the blood and, if low, give B12 injections. Vitamin D – This vitamin is important for bone health. Crohn’s people may be particularly susceptible to vitamin D deficiency which has been found to be much more common than previously thought. Some experts are recommending up to 800 IU each day. Check with your physician regarding vitamin D and calcium supplements as well. Eating a well-balanced diet with adequate whole grains and vegetables will usually provide all the minerals that the body needs. Additionally, most one-a-day vitamin preparations will contain the minimum recommended doses of all minerals. However, there are 3 minerals that may warrant special attention for Crohn’s patients. Calcium – In order to absorb and use calcium you need adequate Vitamin D which you get from sunlight and foods such as milk or supplements. If you take a steroid medication such as prednisone, it is even more important as this drug can deplete the bones of calcium over the long term. A dietary supplement may be needed. Iron – Since iron is absorbed from the small intestine where Crohn’s disease may be most active, there may be a deficiency in iron with the result that iron deficiency anemia can develop. Regular blood tests are usually needed to check for iron deficiency. Selenium – This mineral appears to act like an antioxidant which has beneficial health benefits in the body. Some medical studies have shown that Crohn’s patients may be low in this mineral and may need a supplement. Check with your physician. Prepared, Packaged and Bottled Foods We know that there is a rising incidence of inflammatory bowel disease, especially Crohn’s Disease, in the Western world and America. These increasing numbers parallel the change in our diet that has occurred over the past 100 years. There has been an increase in the saturated fats in the diet that is likely a significant factor. In addition, we now have a very wide variety of prepackaged, prepared and bottled foods that were not present in the past. These are truly manufactured foods. Food manufacturers add a wide range of chemical and other additives to their foods to enhance taste, smell and appearance, to improve mouthfeel and, especially, to increase shelf life. Each of these substances has long ago been approved by the federal Food and Drug Administration (FDA) as GRAS (Generally Accepted As Safe). However, most of them were accepted long before much was known about how they might act in the gut of a Crohn’s patient. Furthermore, we know virtually nothing about how they may interact one with the other. The best choice is to avoid these foods whenever possible. Most of them are present in the packaged foods in the central areas of large food stores. Shop the periphery of the store where fresh foods are sold. You also need to read labels. Be suspicious of foods that have dozens of ingredients and substances listed. In particular, if you don’t recognize the ingredient or word, simply do not buy the food. Look it up in a dictionary or the web. You need to be your own detective. Be suspicious of additives. They may be hurting you. An emulsifier is a chemical that is added to prepared, packaged and bottled foods that we eat. It acts as an emulsion, for instance, emulsifying water and oil in a salad dressing so it is blended and does not need to be shaken. In addition to salad dressings, they are added to a great many of the common foods we all buy and eat, such as ice cream and sauces. They are used to give foods a better taste. They have no calories and so are substituted for many fats and are used in “low calorie” or “no calorie” foods, since many of them have the taste of a fat. Here is a possible problem for the Crohn’s patient. In an earlier section, you will find information on the mucous layer in the intestine. It is also called the biofilm. It is a major defense barrier for the body as it keeps bacteria away from the bowel wall. In fact, it is the invasion of the mucous layer or biofilm by bacteria that is the hallmark of Crohn’s disease. Anything that potentially can damage this valuable layer should be avoided. Here are just some of the emulsifiers found in many of the prepared foods we eat. Polysorbates, such as 40 and 80 Lecithins from eggs Hydroxypropyl methyl cellulose (HPMC), also call hypromellose Carboxymethyl cellulose (CMC) -very commonly used in many products, even toothpaste. Many other celluloses such as methyl cellulose which is stool bulking agent Citrucel Polysorbate 80 and HPMC above have had published research where each of these 2 chemicals badly damaged the mucous layer in the animal’s colon and allowed a Crohn’s like illness to occur. It simply makes sense for a Crohn’s patient to avoid these chemicals wherever possible. Read labels. Do not buy products where you do not know what all the ingredient are. Assume one can be an emulsifier. You need to become educated on labels and food additives so you can protect yourself. Remember that the FDA has approved these ingredients long before we had any idea of how they might react in the intestine in a Crohn’s patient. One final comment. Bread and other food manufacturers are now substituting emulsifiers for gluten, so if you see a food labeled gluten-free, suspect that an emulsifier has been added in its place. Detergents, of course, are cleaning agents that dissolve fats and oils. They may do the same to the wonderful mucous membrane that lines the inside of our intestine. Once dissolved, the underlying cells of the intestine would be exposed to harmful bacteria. No one intentionally ingests detergents. However, they are everywhere around the house, especially the kitchen. They are used to clean dishes and glasses from which we eat food and drink liquids. Some very small dried amounts may remain on dishes that would be particularly harmful to a person who was genetically susceptible to Crohn’s the next time the utensil is used? It is possible. It makes sense to use plenty of clean water to rinse the kitchen utensils thoroughly. Probiotics are beneficial live bacteria taken by mouth that we hope will take up residence in the gut and thereby provide a benefit for the gut and the body. They are now being tested in many different medical disorders. There is some early evidence that certain specific probiotics may be helpful in certain patients with ulcerative colitis. However, in mid-2012 there is still no evidence that any probiotics are helpful in Crohn’s Disease. New research on probiotics is ongoing so this may change. In any event, the use of probiotics for any medical condition should be undertaken only with a physician that is knowledgeable in their use. A Gastroenterologist’s Advice I have seen and treated many patients with Crohn’s disease for many years. Way back then, even before the colonoscopy was invented, we had a pretty good idea of what we were dealing with. It was basically an infection of the wall of the small bowel and colon by the bacteria that normally live within the bowel and usually cause no problem. For some reason, these bacteria became the enemies for CD patients. We knew even then that there was a vague genetic link but really did not know very much beyond that. Now we know down to very specific genes that genetics is critical as to who gets Crohn’s. But, we cannot change the genetic makeup of anyone, at least not yet. But, there have been 2 really huge findings in the last 20 years that have changed. The first research success has been the discovery of the “biologics” as treatment. These biologic drugs are a whole new area of therapy for those people who have severe immunity-related disorders like Crohn’s, rheumatoid arthritis and psoriasis. Remicade is the trade name of the one that has changed the lives for the better for some people with CD. Our researchers, drug companies, and our very physicians deserve a lot of credit for making this happen. The second major change in our understanding of CD is just cresting right now. It is 2 pronged. The first is the spectacular discoveries of how the bacteria within our very gut are of such a vital importance to our very health and well-being. Incredible new research tools have driven these findings. For the Crohn’s patient, this new research has become critical because we now know that most CD patients have an abnormal and unwanted mix of bacteria in their gut. There are simply many more bad ones than good bacteria. This results in some bad things happening within the gut wall, none of which are desirable. Along with this new research and understanding of these lifelong companions within our gut, has come new information that Crohn’s patients themselves can change this bacterial mix in a positive way. Yes, what we now know is that CD is a complex disorder where you need a genetic background to get the disease, but the bacterial load in your gut must change in a bad way to allow the Crohn’s inflammation to occur. We have discovered some risk factors for Crohn’s such as tobacco smoking and a low vitamin D blood level. These seem to increase the risk of getting Crohn’s. But by far the most important finding is in the diet. We used to think that a high protein, meaning a high meat and saturated fat diet, was needed to assure the Crohn’s patient of good nutrition. Now we know that was wrong. It is the fat in the diet, especially the saturated fat, and perhaps excessive meat as well that makes and allows the bacteria makeup to change in a deleterious way. It may be that simple. Reduce the daily saturated fat in the diet from 40% of the calories ingested to 20-25%. More difficult may be the finding that even vegetable fats, especially the omega 6 oils, in excessive doses may increase the risk of getting Crohn’s. Finally, increasing the daily fiber in the diet is likely just as important. It is these fibers that fertilize the very best bacteria and that can push out the bad ones. Using daily prebiotic supplements such as Prebiotin can provide the assurance that enough is being ingested. This diet could be a tough one to follow for many patients. It is different from the standard Western-style diet where meats of all sorts are the central part, along with the saturated fats and low fiber that always accompany this diet. Nevertheless, it would be important for CD persons to know just how much they can contribute to their own well-being by adjusting what goes in their gut. A 2-3 month strict trial on this diet will likely tell you. You perhaps will need a nutritionist to guide you. Do it. It is a lifelong deal. We cannot cure Crohn’s Disease yet, but you, the patient, may have so much more that you can do to help yourself. High fat and low fiber diet increases risk of Crohn’s disease Hou JK, Abraham B, El-Serag H. Dietary intake and risk of developing inflammatory bowel disease: a systematic review of the literature. Am J Gastroenterol, 2011 Apr;106(4):563-73. How food interacts with the gut bacteria in Crohn’s Disease Albenberg LG, Lewis JD, Wu GD. Food and the gut microbiota in inflammatory bowel diseases: a critical connection. Curr Opin Gastroenterol, 2012 Jul;28(4):314-20. High animal protein intake increases the chance of inflammatory bowel disease Jantchou P, Morois S, Clavel-Chapelon F et al. Animal protein intake and risk of inflammatory bowel disease: The E3N prospective study. Am J gastroenterol, 2010 Oct;105(10):2195-201, Epub 2010 May 11. Prebiotic fiber provides health benefits for Crohn’s Disease patients Gauarner F. Inulin and oligofructose: impact on intestinal diseases and disorders. Br J Nutr, 2005 Apr;93 Suppl 1:S61-5. Jackson GI Medical / Prebiotin 1351 Eisenhower Blvd. Building 2, Suite 205 Harrisburg, PA 17113 1-855-466-3488 [email protected] Monday through Friday ~ 8:30 am to 5:00 pm Eastern Time This product is not intended to diagnose, treat, cure or prevent any disease. Jackson GI Medical cannot provide medical advice or guidance. You should seek advice from a medical professional before making any diet or lifestyle changes.
Procedure. The procedure describes how the data was collected, whether by face-to-face, telephone, self-administered questionnaire or online website. It states what was done in time order and in a step by step fashion. For example, an experiment procedure might be: - Consent. Ask the subjects to agree to take part. - Preliminary questionnaire. Gather demographic and other data. - Training. Subjects practice what will be done. - Treatment. Subjects carry out the experiment. - Feedback questionnaire. Gather subject data on the experiment. The description often includes copies of any scripts or tools used, given in an Annex or on a web site, for example: “After entering the room subjects read the study instructions (Annex A), then signed the consent form (Annex B)…” Also describe any procedure deviations, e. g. what was done if subjects talked to a friend when asked not to. Describe the actual data gathering procedure, step by step, including any deviations. Task. The task is what the subjects were asked to do. Its description includes any instruction script given to the subjects. Also describe any training given to reduce initial skill variations. Was there a debrief? The task must represent what is normally done, e.g. if investigating subjects using wikis, providing an extra “Help Sheet” that normal wiki users don’t have doesn’t improve the task, as now the research doesn’t apply to normal wiki users who don’t have your help sheet. Describe the task and any instructions involved, including any scripts given. Pilot study. A pilot study tries out the procedure and method tools on a few cases to uncover problems. Gathering data sounds simple in practice but often things happen that you didn’t expect, e. g. people may not understand some questions. The pilot study data is only used to modify the research method, so it is normal to report these “results” in the method section, e.g. “While trialing the procedure we found that the spiders were mostly active at night so the experiment was conducted between 12pm and 3am.” Report how pilot testing improved the research procedure or tools. Ethical considerations. Any research done at a university must be approved by an ethical committee before it is carried out. For human subjects, questions include “Was consent given?” and “Were the subjects fully informed?” For animals it may include “What measures were taken to minimize pain?”
The chemistry of the cathode used in electric cars is constantly evolving, which means that the cathodes of ten years from now may be significantly different from those used today. To avoid these issues, battery design and smelting methods are being fine-tuned to make them recyclable. Furthermore, the Office for Zero Emission Vehicles is launching a competition to develop on-vehicle solutions for batteries. Redwood Materials, a company launched by a former Tesla CEO, is an example of a company that is trying to improve recycling. Lithium-ion batteries are highly flammable and can result in fire if damaged or faulty. This danger can be reduced by dividing the battery into small cells. Another approach involves using less hazardous electrolytes that are less likely to cause fires and less likely to produce harmful chemicals. Despite these risks, electric vehicles are much safer than their internal combustion engine counterparts. When buying an electric car, it’s important to keep in mind the range. The range depends on a number of factors. Whether the battery is fully charged or not will influence its range. High-speed driving will drain the battery faster than a slow, steady pace. A heavy load will also make the EV consume more energy to accelerate. Modern electric vehicles use lithium-ion or lithium polymer batteries for their power supply. These batteries have a high energy density for their weight. Other rechargeable battery types include lead-acid batteries, which are available in various types: flooded, deep-cycle, and valve-regulated. Other less common types of batteries include zinc-air and sodium nickel chloride. In the near future, electric cars may be the way to go to help combat climate change. The European Union hopes to have 30 million electric cars on European roads by 2030. Although electric vehicles are largely environmentally friendly, they are not without their disadvantages. As a result, there is a concern about battery life. The lithium-ion batteries used in electric cars are recyclable, and can be made into rechargeable batteries. Lithium-ion batteries can last anywhere from four to eight hours of driving. They are also cheap and safe. One of the disadvantages of lead-acid batteries is their short calendar life. Additionally, their performance is poor at low temperatures. While battery-electric cars are more expensive to buy, they are also cheaper to operate. In fact, the total cost of ownership of electric cars may be lower than the cost of fuel for traditional cars. A new world record was recently set by the Japan EV club with a Rimac Concept One electric car, which has a battery capacity of 82 kWh and a driving range of 500 km.
- Reflect on your own journey as a reader and writer. Provide a three-sentence description of your literacy development at each stage of your life. The stages are Early Years, Elementary Years, Middle School Years, High School Years, and College Years. Clearly label each stage. In each stage, you may describe reading and writing experiences, favorite books, people who influenced your journal, and any other memories you may have. - Identify and describe the six approaches to reading provided in Chapter 2 of the textbook. - After watching the read-aloud of Thank You, Mr. Falker, write a response that describes how Mr. Falker gave the “gift” of literacy to Trisha. Then, explain how you can give the “gift” to your future students. - Share a Biblical worldview toward giving the gift of literacy to all students. Provide a reference from the Bible to support your response.
It is called twilight at the interval before sunrise or after sunset, during which the sky is still somewhat illuminated. Twilight occurs because sunlight illuminates the upper layers of the atmosphere. The light is diffused in all directions by the molecules of the air, reaches the observer and still illuminates the environment. The map shows the parts where they are during the day and where they are at night. If you want to know exactly the time that dawns or dusk in a specific place, in the meteorological data we have that information. Why do we use UTC? Universal coordinated time or UTC is the main standard of time by which the world regulates clocks and time. He is one of the several successors closely related to Greenwich Mean Time (GMT). For most common purposes, UTC is synonymous with GMT, but GMT is no longer the most precisely defined standard for the scientific community.
Addition & Subtraction Rock (DVD)Rock 'N Learn Learning math facts is lots of fun when kids "rock out" while learning addition and subtraction. Upbeat music, energetic performers, and colorful action make these video songs lots of fun to learn and sing along. Kids quickly learn sums up to 18 and differences from 18. Ages 6 & up. Approx. 40 minutes. Audio CD & Book version also available. Parents’ Guide to Children’s Media Award Dr. Toy’s 10 Best Audio/Video Products Dr. Toy’s 10 Best Educational Products Dr. Toy’s 100 Best Children’s Products "This is a terrific way to help your child learn math facts. There are great performances and stunning colors in this video. The songs teach the concepts of adding, subtracting, and understanding so that kids can try to answer before the performers do. It teaches facts up to and from 18. It is very useful, helping the child develop confidence in math." – Dr. Toys 10 Best Audio/Video Tapes "Math facts are presented in a fun and entertaining format. Starting off with simple addition and subtraction, the program builds on previously learned skills with each segment. Catchy songs, uncluttered graphics, and engaging performers make this program a plus." – Parents' Guide to Children's Media Award "The facts are clearly shown while being sung. The upbeat, rock music makes the facts easier to remember. This would make a fun review to add-on to a basic math program." - Joy Toll, Eclectic Homeschool Online On our Addition & Subtraction Rock DVD video, the basic concepts are clearly illustrated visually, using familiar kid-appealing objects. Then delayed-answer drills challenge students to beat the performers by solving facts before the answers are read aloud, much like animated flash cards. Addition & Subtraction Rock is great for developing speed, accuracy, and retention for beginning learners as well as older kids. Facts are presented in random order with delayed answers so that learners can check their progress. Learners of all ages at home or in the classroom will love this fun, multisensory way to learn addition and subtraction facts. Addition & Subtraction Rock includes the following: - Add A While (adding 0 and 1) - Adding Up (adding sums to 10) - Take Away (subtracting 0 and 1) - Keep Subtracting (subtracting from numbers up to 10) - Plus Minus Jam (adding or subtracting mixed facts) - Double Time / Half Time (doubling a number or halving it) - Big Number Add (adding sums up to 18) - Having Fun (subtracting from numbers to 18) - Everyone Rock (practice adding and subtracting mixed facts) - Classroom Star (more practice adding and subtracting mixed facts)
Dear Seventh Grade Families; Welcome to the Ann Arbor Public Schools Family Pages. We hope the information you find here assists you in supporting your child while s/he is learning important skills and concepts throughout the seventh grade year. Four key sources inform the middle school Social Studies program; (1) The Michigan Grade Level Content Expectations, (2) the C3 Framework for College, Career and Civic Life for Social Studies State Standards, (3) Social Studies Alive! and (4) History Alive!. The Michigan GLCEs define the state's expectations for what students should know and be able to do in Social Studies at the end of each grade level. Development of units in Atlas is in process. Check back for updates: Atlas: Seventh Grade Social Studies Mapping Labs and Foundations of Social Studies will be taught in both 6th and 7th grades. All other topics may be taught in either 6th or 7th grades and order may vary among the middle schools. Teachers will provide information on the order of topics in each grade. Does Where We Live Determine How We Live? Is It Better to Make Goods Here or There? What's the Right Amount of People? Are Social Structures Fair? What Is the Best Form of Government? Who Is Us? Who Is Them? District Social Studies Department Chair Seventh Grade Social Studies Units"Who am I?" is a question all of us ask at sometime in our lives. It is an especially critical question for middle school students. Students often think about how their identity is formed. While many factors shape our identity, place is especially significant to explore in a World Geography and History course. During the first few days of school, students will explore how place shapes their identities and the identities of their classmates. Students will engage in several activities from the Facing History and Ourselves curriculum. According to Facing History, important questions for student to consider are:1. How does our location shape who we are and what we believe?2. How does the physical environment impact what we do and how we behave?3. How does our location relative to other places influence our ideas about different cultures and our relationships with others?Students will practice of mapping skills and reinforce history and geography concepts learned in prior years. Through the Create-a-Country project, students will develop and apply mapping skills to create and analyze projections of the Earth that reflect the relationship between physical features and human geography. Students will connect their own understanding of place and identity to these maps. Learn more on Atlas: Where We LiveStudents will investigate the Silk Road to learn about the beginnings of globalization, and study the process of globalization, global trade, comparative advantage, design, sourcing, manufacturing and distribution. Students will consider if globalization results in more positive or negative contributions to our communities and society as whole.Learn more on Atlas: Goods Here or There?The number of people on the planet has grown to over seven billion. Population patterns in different countries differ. From personal experiences, students understand how a change in population might negatively or positive affect their lives and the lives of others. For example, students might receive less attention and resources in a classroom with a large population of students. Students will explore case studies of countries across the globe in order to understand population changes. Later, megacities become the focus. Using case studies from around the globe, students analyze photographs, infographics, maps, and other digital resources.Learn more on Atlas: Right Number of People Civilizations, both ancient and modern exhibit evidence of social hierarchies. In some civilizations, the social structure is implicit, while in other it is explicit and government-sanctioned. Some common social structure relationships include: women vs. men; rich vs. poor; rulers vs. subjects; powerful vs. powerless; majority vs. minority groups. Possible case studies include Egyptian social structure; social structure in South Africa during apartheid; fedualism; caste system in India; invention of race; colonization. Learn more on Atlas: Social StructuresGovernments organize communities of people. Many types of governments have been implemented throughout history and exist today. Students will study benefits and drawbacks to each type of government. Class case studies may include monarchy, oligarchy, tyranny, democracy in ancient Greece, direct vs. representative democracy, republic, communism, and socialism.Learn more on Atlas: Government?Balancing the desires of self-governance with the common good is a timeless challenge for nations and their people. As evidenced with the development of the European Union, issues of tariffs, immigration, limited resources, religious identity, and nationalism can hinder cooperation. Ultimately, humans share common goals and needs, even if we pursue them in different ways. How do we move forward with our individual ambitions and pursuits while also collaborating to achieve common goals? Students will research public issues and take action. Learn more on Atlas: Who Is Them? Who Is Us?
Figure 6-37.Displaying CHOP mode. Dashed line CH 1 is the output of one channel, while line CH 2 is the output of the other. The trace moves from left to right because of the sawtooth waveform applied to the horizontal plates. A more detailed analysis shows that the beam moves from CH 1 to CH 2 while the gate is connected to the output from one channel. Then, when the gate samples the output of the CH 2 during time 3 to 4, the beam is at a different vertical LOCATION. (This is assuming that CH 2 is at a different voltage reference.) The beam continues in the sequence 5 to 6, 7 to 8, 9 to 10, and 11 to 12 through the rest of one horizontal sweep. When the chopping frequency is much higher than the horizontal sweep frequency, the number of dashes will be very large. For example, if the chopping occurs at 100 kilohertz and the sweep frequency is 1 kilohertz, each horizontal line would then appear as a series of closely spaced dots, as shown in figure 6-37 view B. As the sweep frequency becomes lower compared to the chopping frequency, the display will show apparently continuous traces; therefore, the CHOP mode is used at low sweep rates. When signals are applied to the channel amplifiers (view A of figure 6-38), the outputs are changed according to the triggering signal (view B). The resultant pattern (view C) on the screen provides a time- base presentation of the signals of each channel.
Start a 10-Day Free Trial to Unlock the Full Review Why Lesson Planet? Find quality lesson planning resources, fast! Share & remix collections to collaborate. Organize your curriculum with collections. Easy! Have time to be more creative & energetic with your students! Students examine how DNA is used in real life and how crime suspects can be identified through their DNA. They identify proteins by their strands and weight on the DNA, and determine which suspect is the criminal in a rape case. 3 Views 16 Downloads
Early Modern universities initially continued the curriculum and research of the Middle Ages: natural philosophy, logic, medicine, theology, mathematics, astronomy (and astrology), law, grammar and rhetoric. Aristotle was prevalent throughout the curriculum, while medicine also depended on Galen and Arabic scholarship. The importance of humanism for changing this state-of-affairs cannot be underestimated. Once humanist professors joined the university faculty, they began to transform the study of grammar and rhetoric through the studia humanitatis. Humanist professors focused on the ability of students to write and speak with distinction, to translate and interpret classical texts, and to live honorable lives. Other scholars within the university were affected by the humanist approaches to learning and their linguistic expertise in relation to ancient texts, as well as the ideology that advocated the ultimate importance of those texts. Professors of medicine such as Niccolò Leoniceno, Thomas Linacre and William Cop were often trained in and taught from a humanist perspective as well as translated important ancient medical texts. The critical mindset imparted by humanism was imperative for changes in universities and scholarship. For instance, Andreas Vesalius was educated in a humanist fashion before producing a translation of Galen, whose ideas he verified through his own dissections. In law, Andreas Alciatus infused the Corpus Juris with a humanist perspective, while Jacques Cujas humanist writings were paramount to his reputation as a jurist. Philipp Melanchthon cited the works of Erasmus as a highly influential guide for connecting theology back to original texts, which was important for the reform at Protestant universities.Galileo Galilei, who taught at the Universities of Pisa and Padua, and Martin Luther, who taught at the University of Wittenberg (as did Melanchthon), also had humanist training. The task of the humanists was to slowly permeate the university; to increase the humanist presence in professorships and chairs, syllabi and textbooks so that published works would demonstrate the humanistic ideal of science and scholarship. Although the initial focus of the humanist scholars in the university was the discovery, exposition and insertion of ancient texts and languages into the university, and the ideas of those texts into society generally, their influence was ultimately quite progressive. The emergence of classical texts brought new ideas and led to a more creative university climate (as the notable list of scholars above attests to). A focus on knowledge coming from self, from the human, has a direct implication for new forms of scholarship and instruction, and was the foundation for what is commonly known as the humanities. This disposition toward knowledge manifested in not simply the translation and propagation of ancient texts, but also their adaptation and expansion. For instance, Vesalius was imperative for advocating the use of Galen, but he also invigorated this text with experimentation, disagreements and further research.The propagation of these texts, especially within the universities, was greatly aided by the emergence of the printing press and the beginning of the use of the vernacular, which allowed for the printing of relatively large texts at reasonable prices.
Excessive precision is a way of concealing how good the numbers are. For example, a 2011 ad for the Volkswagen Passat says it can go 795 miles on a tank of gas. This implies that 800 would be impossible, and that 790 is guaranteed, i.e., an accuracy of 5 miles. Actually, because of driving conditions or one's chosen speed there would be more variation. - "A general rule is to give precisions approximately one tenth the size of the object, unless there is a clear reason for additional precision. Overly precise coordinates can be misleading by implying that the geographic area is smaller than it truly is."
The recurrent laryngeal nerve (RLN) is a branch of the vagus nerve that supplies muscles of the larynx. There are two – right and left, in the human body. The nerves emerge from the vagus nerve at the level of the arch of aorta, and then travel up the side of the trachea to the larynx. The right and left nerves are not symmetrical. The left nerve loops under the arch, and the right nerve travels upwards. The extreme detour of the recurrent laryngeal nerves, about 4.6 metres (15 ft) in the case of giraffes, is evidence of evolution. The nerve’s route would have been direct in the fish-like ancestors of modern tetrapods, traveling from the brain, past the heart, to the gills (as it does in modern fish). Over the course of evolution, as the neck extended, and the heart became lower in the body, the laryngeal nerve was caught on the wrong side of the heart. Natural selection gradually lengthened the nerve by tiny increments to accommodate, resulting in the circuitous route now observed. Adapted from Recurrent_laryngeal_nerve, Wikipedia Why Evolution Is True, by Jerry A. Coyne, Viking Adult, 2009 One of nature’s worst designs is shown by the recurrent laryngeal nerve of mammals. Running from the brain to the larynx, this nerve helps us speak and swallow. The curious thing is that it is much longer than it needs to be. Rather than taking a direct route from the brain to the larynx, a distance of about a foot in humans, the nerve runs down into our chest, loops around the aorta and a ligament derived from an artery, and then travels back up to connect to the larynx. It winds up being three feet long. In giraffes the nerve takes a similar path, but one that runs all the way down that long neck and back up again: a distance fifteen feet longer than the direct route! When I first heard about this strange nerve, I had trouble believing it. Wanting to see for myself, I mustered up my courage to make a trip to the human anatomy lab and inspect my first corpse. An obliging professor showed me the nerve, tracing its course with a pencil down the torso and back up to the throat. This circuitous path of the recurrent laryngeal nerve is not only poor design, but might even be maladaptive. That extra length makes it more prone to injury. It can, for example, be damaged by a blow to the chest, making it hard to talk or swallow. But the pathway makes sense when we understand how the recurrent laryngeal nerve evolved. Like the mammalian aorta itself, it descends from those branchial arches of our fishlike ancestors. In the early fishlike embryos of all vertebrates, the nerve runs from top to bottom alongside the blood vessel of the sixth branchial arch; it is a branch of the larger vagus nerve that travels along the back from the brain. And in adult fish, the nerve remains in that position, connecting the brain to the gills and helping them pump water. During our evolution, the blood vessel from the fifth arch disappeared, and the vessels from the fourth and sixth arches moved downward into the future torso so that they could become the aorta and a ligament connecting the aorta to the pulmonary artery. But the laryngeal nerve, still behind the sixth arch, had to remain connected to the embryonic structures that become the larynx, structures that remained near the brain. As the future aorta evolved backward toward the heart, the laryngeal nerve was forced to evolve backward along with it. It would have been more efficient for the nerve to detour around the aorta, breaking and then re-forming itself on a more direct course, but natural selection couldn’t manage that, for severing and rejoining a nerve is a step that reduces fitness. To keep up with the backward evolution of the aorta, the laryngeal nerve had to become long and recurrent. And that evolutionary path is recapitulated during development, since as embryos we begin with the ancestral fishlike pattern of nerves and blood vessels. In the end, we’re left with bad design.
Combustible dust explosions: Don’t ignore the hazard Between 2006 and 2017, 111 combustible dust incidents resulted in 66 worker deaths and 337 injuries in the United States, according to data from the Chemical Safety Board. So, what is a combustible dust explosion? How do they happen, and what can be done to prevent them? Five elements must be present for a combustible dust explosion to occur: fuel, oxygen, an ignition source, dispersion and confinement. “Dust may accumulate on surfaces and lie undisturbed for years,” the agency states. “Then an initial fire or explosion, known as a primary event, shakes it loose and it ignites.” The resulting pressure then travels throughout a plant or factory and dislodges dust that has been lying dormant, serving as fuel for a secondary explosion. “Most of the fatalities and the devastating injuries have been caused by these secondary dust explosions,” CSB notes. Good housekeeping is a crucial first step toward mitigating dust explosion hazards. “Research has shown that facilities that are well maintained experience fewer fires, explosions and other accidents, and are more profitable as well,” OSHA states. The agency offers additional tips on combustible dust safety:Implement a hazardous dust control program that includes dust inspection, testing and housekeeping. Equip your facility with proper dust collection systems and filters. Regularly inspect both open and hidden areas for dust residue. If ignition sources are found, use cleaning methods that don’t generate dust clouds. Use vacuum cleaners specifically approved for dust collection. Ensure employees are trained on the hazards of combustible dust. Using proper electrical equipment in hazardous locations is crucial to eliminating common ignition sources, OSHA states. Tips on controlling ignition sources include: - Ensuring appropriate electrical equipment and wiring methods are used. - Having an ignition control program, such as grounding and bonding and other methods, for dissipating any electrostatic charge that could be generated while transporting dust through duct work. - Controlling the use of open flames and static electricity. Don’t allow smoking. - Keeping heated systems and surfaces away from combustible dust.
2020 Youth Collective Summit 2019 WNET Youth Collective Summit Reel Works: Let's Talk Bias Beyond the Vote: Gen Z & Civic Engagement PBS LEARNING MEDIA RESOURCES Confronting Bias: Ethics in the Classroom This collection provides teachers with tools to incorporate ethics education in the classroom and foster dialogue about bias. How Unconscious Race Bias Affects Millennials Discuss how implicit bias affects our daily lives with this video and educational resources from PBS NewsHour from March 27, Fighting Prejudice and Bullying \| FILMS BYKIDS Learn how a young girl who immigrated to New York City from Yemen dealt with Islamophobia in this video from FILMS BY KIDS. Why Are Schools Still So Segregated? \| Above the Noise Explore the factors that led to school desegregation and re-segregation in the latest Above the Noise video. Affirmative Action: Should Race Be a Factor in College Admissions? \| Above the Noise Should race be considered in college admissions? Have your students watch the video and respond to the question in KQED Learn Concepts Unwrapped: Implicit Bias This video from Ethics Unwrapped introduces the behavioral ethics bias known as implicit bias. 20th Century Italian Immigration: America the Melting Pot…or Not? Explore the experiences of twentieth century American immigrants alongside renowned chef Tom Colicchio. 8 Tips for Online Teaching Learn to design effective online content for your students that's eye-catching, engaging, and memorable. A Fierce Green Fire A study of the history of the environmental movement, including pollution, climate change and the establishment of Earth Day. Find ways to help your students get the most out of doing math—Cyberchase style! Generously funded by Janet Prindle Seidler.
To calculate the approximate water volume in your pond involves simple arithmetic. There are common two ways to accomplish this approach. The first is numerical approximation, where one takes the rough measurements of the ponds and finds an estimate of the volume. The second is through direct observation, where one times how long it takes to fill the pond and a container of known volume. The benefit to the latter is that it give a much more accurate estimate of the full volume of the pond. The drawback to the fill-method is that it can only be done during whole-pond fills. The drawback to the numerical approximation is that assumptions made in the calculations create an unrefined estimate, which is usually high. These two methods are outlined below. Method 1: Numerical Approximation To calculate a numerical approximation of the volume of a pond, first imagine the pond is a rectangle. Some ponds are shaped like an 'L,' and in that case you could imagine the pond as two rectangles. The approximate surface area of the pond is the length times the width of the rectangle(s). To get a volume, then multiply this surface area by the depth. The best depth to use is the average depth of the pond, but this is difficult to calculate, but we can find an estimation of this depth if we take the shape of the pond into account. For most ponds that have terraced edges that step down to the deepest surface, the average depth of the pond is usually roughly 3/4 of the maximum depth. For ponds that have gently sloping walls all the way down to the deepest surface, making a triangle in the cross-section, the average depth of the pond will be ½ the maximum depth. If you are unsure of the shape or how best to estimate the average depth of your pond, you can use the maximum depth in a pinch. The maximum depth will result in a high estimate as well. If you used feet and inches in the measurement of the length, width and depth, divide the inches by 12 and add this to the number of feet for any one measurement. When you multiply the three measurements together, the result is in cubic feet. To convert cubic feet to gallons, multiply the number of cubic feet by 7.48. Any one measurement, length, width or depth, in feet and inches: (inches / 12) + feet = decimal feet Length x Width x Average Depth = Volume in cubic feet Volume in cubic feet x 7.48 = Volume in gallons For other unit conversions, such as converting cubic feet into liters or cubic meters, see our conversion factors page. Method 2: Direct Observation This method, as stated above, requires that the pond is empty and is going to be filled. In order to measure the volume of your pond using this method, you should have some means of measuring time in seconds and minutes and a large container of a known volume, such as a five gallon bucket or 50-gallon trash can. First, we assume that the rate at which water comes out of your spigot is constant. It is best to describe this method in a series of steps: - Step 1: Fill the container of known volume with water, measuring the amount of time it takes to fill. - Step 2: Fill your empty pond with the same hose fittings and water spigot and measure the amount of time it takes to fill. - Step 3: Divide the time result from step 1 by the time result from step 2. - Step 4: Multiply this number by the known volume of the container filled in step 1. That is the volume of your pond. time to fill pond --------------------- x volume of container = volume of pond time to fill container For unit conversions, such as converting gallons into liters or cubic feet, see our conversion factors page. If you are looking for ways to calculate other helpful quantities when considering building your pond, see our Helpful Calculations page.
This easily understood text will give students a solid back-ground in the basic principles and practices of welding. It first introduces the fundamental theories of the welding processes and then provides practice jobs to allow students to develop essential manipulative skills. The emphasis throughout is on learning by doing. This text presents theory and practice relating to gas, arc, semi-automatic, and automatic welding. It also discusses cutting, brazing, soldering, and plastic welding in accordance with current industrial practices. The content is based upon the recommended practices of the American Welding Society and other leading welding authorities. Each major process is presented as a core program providing a comprehensive treatment of equipment, filler rod materials, joints and welds, and testing and inspection. Metals and their welding characteristics, safety practices, welding symbols, and the fundamentals of print reading are also covered.

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