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Where do physical traits such as height and eye color come from? Biologists say these characteristics are phenotypic (physical) expressions of the genotype—the genetic code. The case for creation can be seen in this amazing genetic code of life. The human body’s trillions of cells use over 75 special kinds of protein and RNA molecules to make one protein following DNA’s detailed instructions. A second genetic code has recently been discovered, adding to the complexity of the already intricate molecule of heredity.1 What was the origin of this code? Was it through chance and time (evolution) or design and organization (creation)? The materialistic explanation (evolution) is the antithesis of biblical creation. Could the origin of the genetic code be just a random event? Hardly.2 In fact, a chance origin of biological information is considered by those involved in such research to be inadequate.3 Advocates of evolution must attempt a purely secular explanation of what is quite obviously an intricately and exquisitely designed code. Such explanations are not sufficient, and never will be, outside of the One who created the genetic code. Evolutionary scientists cannot agree on their theories of the origin of the genetic code. Adam Kun et al stated, “The origin of the genetic code is still not fully understood, despite considerable progress in the last decade.”4 In 2008, an evolutionist from Kazakhstan, Vladimir shCherbak, published a paper asserting the strange idea of an arithmetical origin of the genetic code.5 Arithmetic is the science of computing and is the oldest, most elementary branch of the larger field of mathematics. Roman arithmetic required the use of a counting board, the ancestor of the abacus. shCherbak suggested that a primeval counting frame was responsible for the origin of the genetic code. He claimed the genetic code contains “the zero, decimal syntax and unique summations” and that this refutes “traditional ideas about the stochastic origin of the genetic code.”6 Atheist David Berlinski reminds us that “evolution is a stochastic process [developing in a statistically random way], one that moves forward by means of inconclusive humps.”7 shCherbak continued: Chemical evolution, no matter how long it took, could not possibly have stumbled on the arithmetical language and initialized the decimalization of the genetic code. Physics and chemistry can neither make such abstractions nor fit the genetic code out with them. It seems that the genetic code appeared as pure information like arithmetic did.8 shCherbak is correct; chemical evolution, chemistry, and physics utterly fail to explain in any way the origin of the genetic code. Sadly, his explanation of this code’s appearance via arithmetic through “some primordial abacus at least three and a half billion years ago” is hardly scientific or satisfying.9 “While the biochemical details of this code were unraveled long ago, its origin is still obscure,” lamented evolutionist Tsvi Tlusty.10 Secular explanations for the origin of the sophisticated genetic code point to either the unknown or something like a “primordial abacus.” The only other alternative is a supernatural agency. The genetic code is the result of the purposeful arrangement of parts—design, implying a Designer, as Genesis clearly portrays. - Tejedor, J. R. and J. Valcárcel. 2010. Gene Regulation: Breaking the second genetic code. Nature. 465 (7294): 45-46. - Freeland, S. J. and L. D. Hurst. 1998. The genetic code is one in a million. Journal of Molecular Evolution. 47 (3): 238-248. - de Duve, C. 1996. The Constraints of Chance. Scientific American. 274: 112. - Kun, A. et al. 2008. Catalytic Propensity of Amino Acids. In The Codes of Life: The Rules of Macroevolution. Barbieri, M., ed. New York: Springer Publishers, 39. - shCherbak, V. 2008. The Arithmetical Origin of the Genetic Code. In The Codes of Life: The Rules of Macroevolution. Barbieri, M., ed. New York: Springer Publishers, 153-185. - Ibid, 153. - Berlinski, D. 2009. The Deniable Darwin. Seattle, WA: Discovery Institute Press, 179. - shCherbak, 154. - Ibid, 153. - Tlusty, T. 2010. A colorful origin for the genetic code: Information theory, statistical mechanics and the emergence of molecular codes. Physics of Life Reviews. 7 (3): 362-376. * Mr. Sherwin is Research Associate, Senior Lecturer, and Science Writer at the Institute for Creation Research. Cite this article: Sherwin, F. 2012. Arithmetic and the Genetic Code. Acts & Facts. 41 (2): 17.
Mining for ore has come a long way in the last century. The above images, taken by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) aboard NASA’s Terra satellite, show copper mines in Iran. The image on top was created from visible and near-infrared wavelengths detected by the satellite instrument. The light grayish blue and tan patches are copper mines, while vegetation is red. The lower image was generated from three of ASTER’s short-wave infrared bands. The bright colors in this image correspond to different rock types known as alteration minerals. These alteration minerals oftentimes are good indicators of where copper might be found in the Earth. Scientists at the U.S. Geological Survey are using images such as these to locate alteration minerals all across Iran. Their goal is to test ASTER’s ability to locate copper and other minerals. The scientists hope that in the future, they will be able to employ ASTER and remote sensing instruments like it to create a worldwide map of mineral ore deposits from orbit. To learn more about their work, see Prospecting from Orbit. NASA Earth Observatory images by Robert Simmon, based on data from the NASA/GSFC/MITI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team. Scientists are using images such as these to locate alteration minerals.
See Introduction/aim of research for the background to this work When considering human diets, food requirements and choices it is essential to look at the evolutionary history of our species. This requires looking back at least the couple of hundred thousand years of homo sapiens time on earth and even the previous hundreds of millions of years since our ancestral divergence from other primates. With the relatively recent changes to diet that agriculture and industrialisation have brought, it is especially valuable to consider what has been eaten for most of our evolutionary history. In evolutionary terms, species have a choice between concentrating on eating from a relatively wide or a relatively narrow range of foods. There is then a choice as to whether to concentrate on higher or lower quality foods sources. Due to the danger of poisoning, eating many different foods is challenging for a species as it needs to develop strategies for determining what is safe to eat. Mostly, this is accomplished with some kind of learning process and the more foods to learn about, the bigger the brain needs to be to store and process this information. The benefit to the many-foods strategy is that the species is more secure when there are failures in particular food sources. However, the support of a bigger, more complex brain is a heavy burden on an organism, for example a human brain accounts for around 20% of the body’s energy use (Manning 2004). The choice between high and low quality diets offers a trade-off. High quality foods are usually more difficult to obtain and will generally be subject to more competition as a food source. Being easier to digest though, the species can afford a simpler, smaller and more economical digestive system. This allows the animal greater mobility, beneficial when searching for this type of food. Lower quality diets tend to be easier to find (like grass and mature leaves) but require more complex and specialised digestion apparatus (like the cow’s rumen in which cellulose is broken down by bacteria before being available to the cow). The ancestors of humans and today’s primates chose the complex high-quality diet strategy but our direct descendants took this strategy to extraordinary levels. Since the time hominins devolved from our common ancestor with modern primates around 500 million years ago there has been a massive increase of brain size, intelligence and novel ways to increase food availability and security. This was achieved by, for example, the making and using of tools, development of complex communication abilities, learning to control and use fire and eventually the ability to plant and grow crops and domesticate animals. Meat in the diet of the earliest hominins provided a beneficial high-quality, energy and nutrient-dense supplement to plant foods, which in the wild are rarely nutrient-dense. In environments containing a plethora of poisonous plants threatening the eater with unpleasant to even lethal consequences, animal meat must have been a relatively safe choice when freshly killed. Despite evolving from mainly vegetarian ancestors and having a digestive system which is more like that of a herbivore, hominins gained some of the benefits available to carnivores by regularly adding meat to their diet (Milton 1999). This may have given them the necessary advantage to further enlarge their brains and increase their intelligence. However, as capturing animals for food is a relatively difficult activity, especially for an animal without the evolutionary capabilities of a specialised carnivore, it is likely that hominins became better hunters after their brains and intelligence grew, allowing more complex use of tools and cooperation in hunting. Therefore, initially animal food that allowed the development of the species may have been the most easily obtained such as invertebrates and shellfish. These also happen to be easily eaten without cooking which was a skill developed much later. There has been speculation that the high levels of long chain poly-unsaturated fatty acids (LCPUFAs) found in fish and shellfish could have been instrumental in the evolution of the hominin larger brain. This is because the brain is mostly made up of the same LCPUFAs, specifically arachidonic acid and docosahexaenoic acid. While these can be synthesised from other lipids such as linoleic acid and α-linolenic acid which are available in other foods, the transformation is less efficient. Therefore a diet abundant in these ideal brain nutrients may have been the factor that allowed the brain to enlarge while the rest of the body remained roughly the same. The East African Rift Valley with its abundance of fresh-water lakes would have given access to this kind of diet of fish and shellfish (Broadhurst et al. 1998). Kaplan et al (2000) identify four key characteristics that distinguish humans from other species: long life-span; long juvenile dependency period; social support from older group members and male support through food-provisioning. They theorise that these characteristics and our advanced intelligence are “co-evolved responses to a dietary shift toward high-quality, nutrient-dense, and difficult-to-acquire food resources” (Kaplan et al. 2000). Their research goes on to demonstrate the extraordinary level of skill and learning that is required for traditional human hunting strategies. By analysing modern hunter-gatherers, they found that men’s hunting skills did not peak until they reached their 30s, well into adulthood. Due to the considerable nutritional pay-off hunting provides, in most of the studies it was found that adult male hunters were the greatest providers of food energy in their communities. Females concentrated on gathering, plant foods especially, an activity that is easier to achieve while child-rearing. It is difficult to prove exactly when hominins began to control and use fire but evidence points to its use by around 500,000 years ago, possibly as early as 1.7 million years ago (James 1989). Cooking of foods which developed some time after that was another key factor that allowed our ancestors to advance as they did. Cooking offered unique advantages to the diet and appears to have been an essential part of our evolution. Cooking of food equates to a type of pre-digestion, reducing the energy required to digest food in the body and this may have allowed the human intestinal tract to shorten over time. Cooking made some previously inedible foods edible, considerably reduced some of the dangers from food-based pathogens and was revolutionary for our gastronomic progress, multiplying the sensual aspects of food through different cooking methods. The cooking of meat has an especially transformative action in terms of taste, safety and ease of eating/digesting. It is noticeable that very little meat is eaten without cooking or similar processing in either modern or traditional diets. Professor Sonia Ragir (2000), writing in the Journal of Evolutionary Anthropology puts the use of fire for food preparation as one of the four key factors in the transformation of our evolutionary ancestors into modern humans along with: the search for and eating of rhizomes and tubers (which are not generally eaten by other primates and can provide significant amounts of nutrition when processed correctly); the use of tools for hunting, trapping and butchering sometimes large animals; and the group-sharing of meat that had been hunted. As our hominin ancestors spread out around the world, their unique flexibility and ability to survive on different food sources allowed them to thrive in otherwise hostile environments. There is extensive archaeological evidence of their lives from diverse parts of the world. As they travelled further from the equator, and encountered more extreme environments, the importance of meat in the diet became greater due to the seasonal and less extensive nature of wild plant foods. Studying exactly what our ancestors ate between the emergence of homo sapiens and the historical recording of dietary norms presents a challenge due to the lack of preservation of most food evidence over that time-scale. Some data can be gained from archaeological studies and carbon analysis of human remains. Study of remaining hunter-gatherer communities can also give valuable insights, although very few of these groups have been unaffected by the thousands of years of human agricultural development. Various studies such as Richards et al (2000) have analysed hominin bones in Europe for the stable isotope (δ13C and δ15N) ratios which can indicate the proportion of animal to plant food in their diet (Richards et al. 2000). These studies suggest that European Neanderthal and later hunter-gather diets were almost completely carnivorous. Further research such as done by Richards (2003) find a sudden shift in British diet at the beginning of the Neolithic period, around 5000 years ago. Again analysis of the stable isotopes in bone remains show an almost complete abandonment of seafood in the diet for land-based foods. This shift would have occurred around the time that agricultural and animal husbandry techniques arrived in the area. When Cordain et al (2000) analysed the diets of 229 modern hunter-gatherer societies listed in the Ethnographic Atlas they found that “most (73%) of the worldwide hunter-gatherers derived > 50% (56–65%) of their subsistence from animal foods (hunted and fished), whereas only 13.5% of worldwide hunter-gatherers derived > 50% (56–65%) of their subsistence from gathered plant foods” The importance of animal foods in this analysis generally increased with greater distance from equatorial regions. These studies show how important animal-derived foods have been in our evolutionary diet especially in the higher latitudes. With this high dependence on meat and long history of consumption in the evolutionary diet, it is interesting to note that there been virtually no evolutionary adaptation of our bodies to this diet (Milton 2000). Our digestive system remains almost the same as our completely herbivorous ancestors and we see none of the digestive adaptations that carnivorous animals have. While our digestive system is not best suited to processing lots of meat, it copes well enough that there has not been evolutionary pressure for adaptation. Similar change of diet without significant adaptation can be seen in reverse in some animals such as the giant panda which has a carnivorous evolutionary history but has evolved to eat a vegetarian diet. High meat consumption can be difficult to sustain for humans as protein is not a practical primary source of energy for the human body due to the high energetic cost of metabolising it. Therefore, a diet high in lean animal meat can be inadequate to provide full nutrition. To get around this, animals with higher fat content need to be eaten or plant foods can provide more of the dietary energy. Larger herbivores typically have greater stores of fat and overall food energy making them especially valuable as a food source. A mammoth, for instance could have provided the food energy of a hundred large deer (Smil 2003) and supplied a gigantic supply of food energy compared to that expended in obtaining it. This preference for large herbivores such as the mammoth may be implicated in the extinction of these species, as seen for example in the North American mega-faunal extinction at the end of the Pleistocene era (Smil 2003). Due to the protein metabolisation problem, plant foods have always been a valued part of the diet when available. Plant carbohydrates are also probably the most efficient source for convertion to the glucose that our large brains require as energy. In areas where prey was predominantly lean and large herbivores rare or absent, plant food had to provide significant proportions of the total dietary energy. Large starchy roots have played an important part in many cultures due to the concentration of food energy they can provide. Often these roots need processing such as grinding, leaching or cooking to remove inedible substances. Our reliance on diet for other essential nutrients such as vitamin C has meant that varied diets encompassing available edible fruits, nuts, seeds, tubers, leaves etc. helped ensure good nutritional health. Diets with a mix of different foods and food groups have helped prevent boredom and nutritional deficiency which is perhaps part of the reason our bodies reward us with pleasure when we eat diverse, quality foods. When agricultural practices were developed to the east of the Mediterranean, the ability to have a greater control over the supply of edible plants must have been especially valuable in an area lacking the botanical abundance of tropical areas. The other field of agriculture, livestock farming with its domestication of animals provided an easier and more reliable way of supplying meat in the diet and added the possibility of a whole new food source through the collection of animal milk. Broadhurst CL, Cunnane SC & Crawford MA. 1998. Rift Valley lake fish and shellfish provided brain-specific nutrition for early Homo. British Journal of Nutrition 79, 3-21. Cordain L, Brand Miller J, Eaton SB, Mann N, Holt SHA and Speth JD. 2000. Plant-animal subsistence ratios and macronutrient energy estimations in worldwide hunter-gatherer diets. American Journal of Clinical Nutrition 2000;71:682–92 James, Steven R. 1989. Hominid Use of Fire in the Lower and Middle Pleistocene – A Review of the Evidence. Current Anthropology, Vol. 30, No. 1 (Feb., 1989), pp. 1-26 Kaplan H, Hill K, Lancaster J, Magdalena Hurtado A. 2000. A theory of human life history evolution: Diet, intelligence, and longevity. Evolutionary Anthropology: Issues, News, and Reviews 9:4, 156-185 Manning, Richard. 2004. Against The Grain: How agriculture has hijacked civilization. North Point Press. Milton, Karen. 1999. Hypothesis to explain role of meat eating in humans, Evolutionary Anthropology Milton, Katharine. 2000. Hunter-gatherer diets—a different perspective. American Journal of Clinical Nutrition 2000;71:665–7 Ragir Sonia. 2000. Diet and food preparation: rethinking early hominid behavior. Evolutionary Anthropology 9, 153–155. Richards MP, Pettitt PB, Trinkaus E, Smith FH, Paunovic M and Karavanic I. 2000. Neanderthal diet at Vindija and Neanderthal predation: The evidence from stable isotopes, Proceedings of the National Academy of Sciences U S A 2000;97:7663–6 Richards, Martin. 2003. The Neolithic Invasion of Europe. Annual Revue of Anthropology 2003. 32:135–62 Smil, Vaclav. 2003. Eating Meat: Evolution, Patterns, and Consequences. Population and Development Review 28:4, 599-639
Make a Spitting Monster Toy In this science experiment, kids explore gravity and air pressure while making a spitting monster toy that is perfect for Halloween! The forces of gravity and air pressure act on the water inside the bottle. Gravity is a force that pulls everything down toward the earth. It is pulling downward on the water inside the bottle (and the bottle itself) -- but gravity's pull on the water is the same whether or not the cap is on the bottle, so this not what is controlling the "spitting." It's changes in air pressure make the water squirt out: when the cap is loosened, air can get inside the bottle, and the air pressure begins to force the water down and out. When the cap is tightened, the air pressure stabilizes (meaning, it becomes the same both inside and outside of the bottle) and so it stops pushing the water out of the bottle. Only an adult should make the hole in the water bottle. As always, be careful when using force with a sharp object. - Plastic water bottle with lid - green preferred - 1 of this item per student - Craft materials - Sharp object to make a small hole - Sink, bucket or similar Be sure the bottle is at room temperature. If it is cold, it will "sweat" and you won't be able to decorate. Peel off any labels. (Note: if you are doing this with a water bottle that has never been opened, there is no need to empty the bottle first; just be sure to leave the lid on. This is a great way to do this activity with a large group of kids, as you can skip the later step of filling the bottles with water.) ADULT SUPERVISION: Poke a small hole in the bottle about 2" up from the bottom using an awl, sharp knife tip or similar. This will be the "mouth." (Note that when we made the model in the video, the knife made an uneven hole, which made it look like water is spitting out of two sides of the mouth. Also note that it is OK to do this with a bottle that is already full of water, provided the cap is on tightly. Water should only come out when you squeeze the bottle.) Holding your thumb over the hole, fill the bottle with water and screw on the cap tightly. Once the cap is on, no water should come out of the hole on the side unless you squeeze the bottle. Now decorate the bottle to look like a monster. Be sure to put the "mouth" around the hole in the side. To experiment, hold the bottle over something to contain the pouring water and slowly unscrew the cap. Water will “magically” spit out of the mouth. Now screw the cap back on -- the bottle stops spitting! Repeat until the water is gone; refill as many times as you'd like. (Note that any pressure on the sides of the bottle will make a little water come out, so to create the illusion of a magically spitting bottle, be careful not to squeeze the sides.)
Bhedābheda Vedānta (dvaitadvaita) is one of the several traditions of Vedānta philosophy in India. “Bhedābheda” is a Sanskrit word meaning “difference and non-difference.” Bhedābheda reconciles the positions of two other major schools of Vedānta, Advaita (non-dual) Vedānta, which claims the individual self is completely identical to Brahman, and Dvaita (Dualist) Vedānta, which teaches that there is a complete difference between the individual self and Brahman. Among the early Bhedabhedans were Ashmarathya, Bhartrprapancha, Bhaskara, and Yadava, the teacher of Ramanuja. Medieval Bhedābheda thinkers included Nimbārka (thirteenth century C.E.), Vallabha (1479-1531 C.E.), Rajasthan, and Caitanya. There are substantial philosophical disagreements among the many Bhedābheda thinkers, and each thinker within the Bhedābheda Vedānta tradition has his own understanding of the precise meanings of the philosophical terms, “difference” and “non-difference.” Their philosophies share some common characteristics, such as the understanding that the individual self (jīvātman) is both different and not-different from the ultimate reality known as Brahman; the doctrine that the phenomenal world is a real transformation of Brahman (Pariṇāmavāda); and the doctrine that liberation can only be attained by means of a combination of knowledge and ritual action (Jñānakarmasamuccayavāda), not by knowledge alone. Bhedābheda Vedāntic ideas can traced to some of the very oldest Vedāntic texts, including possibly Bādarāyaṇa’s Brahma Sūtra (approximately fourth century C.E.). The history of Bhedābheda in India is at least as old as the seventh century C.E. and spans into the present day. Bhedābheda ideas also had a powerful influence on the devotional (bhakti) schools of India’s medieval period. Among the early Bhedabhedans were Ashmarathya, Bhartrprapancha, Bhaskara, and Yadava, the teacher of Ramanuja. Medieval Bhedābheda thinkers included Nimbārka (thirteenth century C.E.), founder of the Nimbārka Sampraday which is now centered in [Vrindavana|Vrindāvan]], Vallabha (1479-1531 C.E.), founder of the Puṣṭimārga devotional sect now centered in Nathdwara, Rajasthan, and Caitanya (1485-1533 C.E.), the founder of the Gaudīya Vaiṣṇava sect based in the northeastern Indian state of West Bengal. As the sparks issuing from a fire are not absolutely different from the fire, because they participate in the nature of the fire; and, on the other hand, are not absolutely non-diffeerent from the fire, because in that case they could neither be distinguished from the fire nor from each other; so the individual selves also—which are the effects of Brahman—are not absolutely different from Brahamn, because that would mean they are not of the nature of intelligence; nor absolutely non-different from Brahman, because in that case they could not be distinguished from each other, and because, if they were identical with Brahman and therefore omniscient, it would be useless to give them any instruction. Hence the individual selves are somehow different from Brahman and somehow non-different. Numerous scholars have concluded that Bādarāyaṇa’s Brahma Sūtra (fourth century C.E.), one of the foundational texts common to all Vedānta schools, was written from a Bhedābheda Vedāntic viewpoint. While that claim is disputed by other schools, there is little doubt that Bhedābheda predates Śaṅkara’s Advaita Vedānta. In his commentary on the Bṛhadāraṇyaka Upaniṣad, written in the eighth Śaṅkara, repeatedly attacks the interpretations of an earlier Vedāntin named Bhartṛprapañca, who characterized the relation between Brahman and individual souls as one of “difference and non-difference.” One of the central disagreements between the two is that Śaṅkara claims that Brahman’s entire creation is a mere appearance or illusion (vivarta), while Bhartṛprapañca maintains that it is real (Hiriyanna 1957: Vol. 2, p. 6-16). Bhāskara (eighth-ninth centuries), who was either a younger contemporary of Śaṅkara or perhaps lived slightly after Śaṅkara, wrote a commentary on the Brahma Sūtra to defend the earlier claims of Bhedābhedavādins against Śaṅkara’s interpretation of the Brahma Sūtra. Although he never mentions Śaṅkara by name, he makes it clear from the beginning that his primary intention in commenting on the Brahma Sūtra is to oppose some predecessor: “I am writing a commentary on this sūtra in order to obstruct those commentators who have concealed its ideas and replaced them with their own” (Bhāskara, 1903: p. 1). Bhāskara was the first of a long line of Vedāntic authors who refuted Advaita (non-duality), and many of the standard arguments used against Advaita originated with his commentary, assuming he did not borrow them from an even earlier source. The collective Advaita tradition seems to have regarded Baskara as an annoyance. An example is the fourteenth century Śaṅkaradigvijaya of Mādhava, which depicts a “Bhaṭṭa Bhāskara” as a haughty and famous Bhedābhedavādin whom Śaṅkara defeats in a lengthy debate (including Rāmānuja and Madhva, not to mention numerous Bhedābhedavādins). According to Bhāskara (Varttika, eleventh century C.E.), reality was like the ocean, of which the world of experience was a part just as the waves are parts of the ocean. They were neither absolutely one with it nor different from it. Bhāskara’s doctrine, called Aupādhika Bhedābhedavāda (“Difference and Non-difference Based on Limiting Conditions”), maintained that the difference between the material world and Brahman was due to limiting conditions, and held that both identity and difference were equally real. As the causal principle, Brahman was non-dual, absolutely formless, pure being and intelligence; the same Brahman, manifested as effects, became the world of plurality. Through modification (parinama) Brahman evolved as the world. When matter limited Brahman, it became the individual soul (jiva). Yādavaprakāśa, the teacher of Ramanuja, was a Bhedābhedavādin. His works have been lost, but his basic views can be understood from Rāmānuja and one of Rāmānuja’s commentators, Sudarśanasῡri. Rāmānuja depicts Yādavaprakāśa as an exponent of Svābhāvika Bhedābhedavāda (Natural Difference and Non-Difference), the view that, in its very nature, Brahman is both different and not different than the world, and that difference is not simply due to artificial limiting conditions. He accepted that Brahman really evolves into this material world, but did not accept that Brahman suffers bondage and enjoys liberation. God (Ishvara), souls (chit), and matter (achit) were not different substances, but modes of the same substance, different states of Brahman. Another characteristic of Yādavaprakāśa’s thought was his repeated insistence that Brahman has the substance of pure existence (sanmātradravya). Nimbarka (fourteenth century), advocated Svābhāvika Bhedābhedavāda (Natural Difference and Non-Difference). Like Yadava and his pupil, Ramanuja, he defined three categories of existence, God (Isvara), souls (chit), and matter (achit). God (Isvara) existed independently and by Himself, but the existence of souls and matter was dependent upon God. Souls and matter had attributes and capacities which were different from God (Isvara), but at the same time they were not different from God because they could not exist independently of Him. “Difference” or “duality” referred to the separate but dependent existence of soul and matter (para-tantra-satta-bhava), while “non-difference” or “non-duality” meant that it was impossible for soul and matter to exist independently of God (svatantra-satta-bhava). Nimbarka perceived the relation between Brahman, and souls (chit) and the universe (achit) as a relation of natural difference-non-difference (svabhavika-bhedabheda), just like the relationship between the sun and its rays, or a snake and its coil. Just as the coil was nothing but the snake, yet different from it; just as the different kinds of stones, though nothing but earth, were yet different from it; so the souls and the universe, though nothing but Brahman (brahmatmaka), were different from Him because of their own peculiar natures and attributes. According to Nimbarka, Brahman (God), souls (chit) and matter or the universe (achit) were three equally real and co-eternal realities. Brahman was the Controller (niyantr), the soul was the enjoyer (bhoktr), and the material universe was the object enjoyed (bhogya). God, the highest Brahman, ruler of the universe, was by His nature free from all defects and the abode of all goodness. God was the efficient cause of the universe because, as Lord of Karma and internal ruler of souls, He brought about creation so that the souls would be able to reap the consequences of their karma; God was the material cause of the universe because creation was a manifestation of His powers of soul (chit) and matter (achit); creation was a transformation (parinama) of God’s powers. Chaitanya (1485-1533) initiated a school of thought known as Acintya Bhedābhedavāda (Inconceivable Difference and Non-difference). Although Caitanya never wrote down his teachings, numerous disciples and followers authored works based on his philosophy. God is free from all differences, homogeneous, heterogeneous and internal, and yet He really manifests Himself as the world and souls, through His powers which are identical and yet different to Him. He is the efficient cause of the universe, and in association with His powers, He is the material cause. The notion of “inconceivability” (acintyatva), that God’s power is unthinkable and indescribable, is a central concept used to reconcile apparently contradictory notions, such as the simultaneous oneness and multiplicity of Brahman, or the difference and non-difference of God and his powers. The last major Bhedābheda thinker in pre-modern India, Vijñānabhikṣu (sixteenth century), sought to show the ultimate unity of the schools of Vedānta, Sāṅkhya, Yoga, and Nyāya, and is most well known today for commentaries on Sāṅkhya and Yoga texts. His earliest works, such as his Bhedābheda Vedāntic commentary on the Brahma Sūtras, explained the concepts of difference and non-difference in terms of separation and non-separation (Ram 1995). Although for him the fundamental relation of the individual self and Brahman was one of non-separation, he accepted the Sāṅkhya-Yoga analysis of the individual selves as multiple and separate from one another, as long as it was understood that this state of separation was temporary and adventitious. All the Bhedabheda thinkers grounded their philosophies firmly in the Vedas, and many criticized the Advaitans of leaning towards Buddhism and interpreting the Vedas incorrectly. Though they differed in their definitions of “difference” and “non-difference,” their systems shared some common characteristics, such as the understanding that the individual self (jīvātman) is both different and not-different from the ultimate reality known as Brahman; the doctrine that the phenomenal world is a real transformation of Brahman (Pariṇāmavāda); and the doctrine that liberation can only be attained by means of a combination of knowledge and ritual action, (Jñānakarmasamuccayavāda), as prescribed by the Vedas, not by knowledge alone. During the medieval period, Bhedābheda Vedānta became closely associated with the movement of bhakti devotionalism. Bhedābheda takes activity in the world (karman) seriously, believing that activities in the world are real, and produce real effects; it is, therefore, conducive to the notion of bhakti, or a life of devotional acts and thoughts. Early Bhedābhedans, however, were concerned instead with defending the importance of Brahmanical ritual orthodoxy. Bhedābheda reconciles the positions of two other major schools of Vedānta, Advaita (Non-dual) Vedānta which claims the individual self is completely identical to Brahman, and Dvaita (Dualist) Vedānta which teaches that there is a complete difference between the individual self and Brahman. Bhedābhedavāda offers the possibility of bridging these two alternatives, by offering both a real God possessing qualities and the possibility of personal participation in that Godhead. All links retrieved June 6, 2016. New World Encyclopedia writers and editors rewrote and completed the Wikipedia article in accordance with New World Encyclopedia standards. This article abides by terms of the Creative Commons CC-by-sa 3.0 License (CC-by-sa), which may be used and disseminated with proper attribution. Credit is due under the terms of this license that can reference both the New World Encyclopedia contributors and the selfless volunteer contributors of the Wikimedia Foundation. To cite this article click here for a list of acceptable citing formats.The history of earlier contributions by wikipedians is accessible to researchers here: The history of this article since it was imported to New World Encyclopedia:
Moon Cycles and Fish Behaviour As well as playing an important part in the tidal behaviour of the world’s seas and oceans, the phases of the moon are also thought to play an additional part in the behaviour of many of Australia’s most important fish. Whilst it is an indisputable fact that tidal movements can affect the levels of fish stocks in prime fishing locations, there are other beliefs held by anglers and the indigenous population that the moon can have an important effect on the feeding and breeding patterns of fish. Although some anglers have opined that the moon can affect freshwater fish as well, the most significant changes can be seen on saltwater species, especially for those species of fish which swim closer to the shoreline and those which frequent estuaries or coastal bays. In terms of fish activity, peak periods tend to occur when the moon is directly overhead and when the moon is directly below (i.e. when it is directly on the other side of the Earth). Minor periods of activity also occur when the moon is half way between these 2 “major” points. Therefore, there tends to be 4 periods of increased activity per day, when the fish tend to be noticeably more active than they are other times of the day. These 4 periods of activity should occur regardless of what phase the moon is in. Many anglers refer to the periods surrounding these spikes in activity as “dead zones”, because of the vast reductions in the numbers of fish which are active during these times. In terms of the phases of the moon, the number of fish feeding at night (and therefore ready to take your bait) often increases when there is a full moon. Larger fish take advantage of the fact that baitfish are illuminated by the light of the full moon, in order to feed. However, if you choose to fish at night, take extra care, especially if you are out on a boat. In general, studies (and angler lore) suggest that many species of saltwater fish are the most active on the 4 days leading up to the full moon and the 4 days directly after the full moon. During these few days, fish activity should increase in general, regardless of what time of day it is or whether it is a “major” or “minor” phase in accordance with the position of the moon. If you regularly fish for the same species, in the same area, you can begin keeping your own notes about fish stock levels, and you can check whether stock levels correlate significantly with moon phases. If you find that the only day which you have free for fishing is a day which should be a poor one for fish, according to tidal phases and moon cycles, do not despair, because plenty of anglers have reported that they are still able to land an excellent catch against all odds. Finding inventive ways to make your day a success can be half the fun!
Text-to-speech is a process through which text is rendered as digital audio and then "spoken." Most text-to-speech engines can be categorized by the method that they use to translate phonemes into audible sound. Subword segments are acquired by recording many hours of a human voice and painstakingly identifying the beginning and ending of phonemes. Although this technique can produce a more realistic voice, it takes a considerable amount of work to create a new voice and the voice is not localizable because the phonemes are specific to the speaker's language. Text-to-speech should be used to audibly communicate information to the user, when digital audio recordings are inadequate. Generally, text-to-speech is better than audio recordings when: Text-to-speech also offers a number of benefits. In general, text-to-speech is most useful for short phrases or for situations when prerecording is not practical. Text-to-speech has the following practical uses: The specific use of text-to-speech will depend on the application. Here are some sample ideas and their uses: Games and Edutainment Text-to-speech is useful in games and edutainment to allow the characters in the application to "talk" to the user instead of displaying speech balloons. Of course, it's also possible to have recordings of the speech. An application would use text-to-speech instead of recordings in the following cases: Look in the Text-To-Speech for Telephony article for a full description of telephony. A speech application requires certain hardware and software on the user's computer to run. Not all computers have the memory, speed, or speakers required to support speech, so it is a good idea to design the application so that speech is optional. These hardware and software requirements should be considered when designing a speech application: Text-to-Speech Voice Quality Most text-to-speech engines can render individual words successfully. However, as soon as the engine speaks a sentence, it is easy to identify the voice as synthesized because it lacks human prosody -- i.e., the inflection, accent, and timing of speech. For this reason, most text-to-speech voices are difficult to listen to and require concentration to understand, especially for more than a few words at a time. Some engines allow an application to define text-to-speech segments with human prosody attached, making the synthesized voice much clearer. The engine provides this capability by prerecording a human voice and allowing the application developer to transfer its intonation and speed to the text being spoken. In effect, this acts as a highly effective voice compression algorithm. Although text with prosody attached requires more storage than ASCII text (1K per minute compared to a few hundred bytes per minute), it requires considerably less storage than prerecorded speech, which requires at least 30K per minute. These factors also influence the quality of a synthesized voice: If an engine mispronounces a word, the only way that the user can change the pronunciation is by entering either the phonemes, which is not an easy task, or by choosing a series of "sound-alike" words that combine to make the correct pronunciation. Creating and Localizing Text-to-Speech Voices Creating a new voice for an engine that uses synthesis can be done relatively quickly by altering a few parameters of an existing voice. However, although the pitch and timbre of the new voice are different, it uses the same speaking style and prosody rules as the existing voice. Creating a new voice for a text-to-speech engine that uses diphone concatenation can take a considerable amount of work, because the diphones must be acquired by recording a human voice and identifying the beginning and ending of phonemes, which are specific to the speaker's language. Whether a text-to-speech engine uses synthesis or diphone concatenation, the work of localizing an engine for a new language requires a skilled linguist to design pronunciation and prosody rules and reprogram the engine to simulate the sound of the language's phonemes. In addition, diphone-concatenation systems require a new voice to be constructed for the new language. As a consequence, most engines support only five to ten major languages. Using Text-to-Speech for Short Phrases An application should use text-to-speech only for short phrases or notifications, not for reading long passages of text. Because listening to a synthesized voice read more than a few sentences requires more concentration, a user can become irritated. Presenting Important Information Visually An application should communicate critical information visually as well as audibly, and it should not rely solely on text-to-speech to communicate important information. The user can miss spoken messages for a variety of reasons, such as not having speakers or headphones attached to the computer, being distracted or out of earshot when the application speaks, or the user may simply have turned off text-to-speech. Avoiding a Mix of Text-to-Speech and Recorded Voice The synthesized voice provided by even the best text-to-speech engine is noticeably different from that provided by a digital-audio recording. Mixing the two in the same utterance can be disturbing to the user (and usually makes the text-to-speech voice sound worse by comparison). For example, to have an application speak "The number is 56,738," you should not prerecord "The number is" and use text-to-speech to speak the numbers. You should either prerecord everything or use text-to-speech for everything. Making Text-to-Speech Optional An application should always allow the user to turn off text-to-speech. Some users work in environments in which a talking computer may distract coworkers or in which privacy may be important. Also, some users may simply dislike the sound of a synthesized voice. Where the Engine Comes From Of course, for text-to-speech to work on an end user's PC the system must have a text-to-speech engine installed on it. The application has two choices: The application can come bundled with a text-to-speech engine and install it itself. This guarantees that text-to-speech will be installed and also guarantees a certain level of quality from the text-to-speech. However, if an application does this, royalties will need to be paid to the engine vendor. Alternatively, an application can assume that the text-to-speech engine is already on the PC or that the user will purchase one if they wish to use text-to-speech. The user may already have text-to-speech because many PCs and sound cards will come bundled with an engine, or, the user may have purchased another application that included an engine. If the user has no text-to-speech engine installed then the application can tell the user that they need to purchase a text-to-speech engine and install it. Several engine vendors offer retail versions of their engines.
|- Up -||Next >>| Let's begin by going through some basic ideas about context-free grammars. I'll start by using simple grammars that generate formal languages, rather than natural language examples, as the formal examples are typically shorter. Here's a simple context free grammar (CFG): Some terminology. The is called the rewrite arrow, and the four expressions listed above are called context free rules (you may also see them called rewrite rules, or something similar). Apart from the , there are two sorts of symbols in this grammar: terminal symbols and non-terminal symbols. In the above grammar, the terminal symbols are `a' and `b', and the non-terminal symbols are `S', `A', and `B'. Terminal symbols never occur to the left of a rewrite arrow. Non-terminal symbols may occur either to the right or the left of the rewrite arrow (for example, the `S' in the above grammar occurs both to the right and the left of in the second rule). Every context free grammar has one special symbol, the start or sentence symbol, which is usually written `S'. Some context free grammars also use another special symbol, namely , for the empty string. The symbol can only occur on the right hand side of context free rules. For example, we could add the rule to the above grammar, but we could not add . The simplest interpretation of context free grammars is the rewrite interpretation. This views CFGs as rules which let us rewrite the start symbol S to other strings: each rule is interpreted as saying that we can replace an occurrence of the symbol on the left side of the rule by the symbol(s) on the right side. For example, the above grammar lets us rewrite `S' to `aabb': Such a sequence is called a derivation of the symbols in the last row. For example, the above sequence is a derivation of the string `aabb'. Note that there may be many derivations of the same string. For example, is another derivation of `aabb'. Why are such grammars called `context free'? Because all rules contain only one symbol on the left hand side --- and wherever we see that symbol while doing a derivation, we are free to replace it with the stuff on the right hand side. That is, the `context' in which a symbol on the left hand side of a rule occurs is unimportant --- we can always use the rule to make the rewrite while doing a derivation. (There are more complex kinds of grammars, with more than one symbol on the left hand side of the rewrite arrow, in which the symbols to the right and left have to be taken into account before making a rewrite. Such grammars can be linguistically important, but we won't study them in this course.) The language generated by a context free grammar is the set of terminal symbols that can be derived starting from the start symbol `S'. For example, the above grammar generates the language (the language consisting of all strings consisting of a block of as followed by a block of bs of equal length, except the empty string). And if we added the rule to this grammar we would generate the language . A language is called context free if it is generated by some context free grammar. For example, the language is context free, and so is the language , for we have just seen that these can be produced by CFGs. Not all languages are context free. For example, is not. That is, no matter how hard you try to find CFG rules that generate this language, you won't succeed. No CFG can do the job. While the rewrite interpretation of CFGs is important, there is a more fundamental way of thinking about CFGs, namely as tree admissibility rules. A parse tree is a finite tree all of whose interior nodes (that is, nodes with daughters) are licensed or admitted by a grammar rule. What does this mean? Let's look at an example: This tree is licensed by our grammar --- that is, the presence of every node with daughters can be justified by some rule. For example. the top node is ok, because under the tree admissibility interpretation we read as saying: A tree node labelled can have exactly three daughters, labelled (reading left to right) , , and . The node labelled A is ok, because under the tree admissibility we read the rule as saying: A tree node labelled can have exactly one daughter which is labelled . Similarly, all the other nodes with daughters are `justified' or `admitted' by other rules (the terminal nodes of the tree don't need to be justified). If you think about it, you will see there is a close correspondence between parse trees and derivations: every derivation corresponds to a parse tree, and every parse tree corresponds to (maybe many) derivations. For example, the tree above corresponds to both our earlier derivations of `aabb'. The tree admissibility interpretation is important for two reasons. First, it is the linguistically most fundamental interpretation. We don't think of natural language as a bunch of strings that need rewriting --- we think of natural language sentences, and noun phrases and so on as having structure, tree structure. Thus we think of CFG rules as telling us which tree structures we have. Second, the idea of parse trees brings us to an important concept: ambiguity. A string is ambiguous if it has two distinct parse trees. Note: I said `parse trees', not `derivations'. For example, we derived the string `aabb' in two different ways from our little grammar --- but both ways correspond to the same derivation tree. That is, the string `aabb' is not ambiguous in this grammar. And in fact, no string this grammar generates is ambiguous. But some grammars do generate ambiguous strings. One of this week's exercises is to come up with a simple example of such a grammar. The above ideas adapt straightforwardly to natural languages. But with natural languages it is useful to draw a distinction between rules which have syntactic categories on the right hand side, and rules which have only words on the right hand side (these are called lexical rules). Here's a simple grammar of English. First we have the following rules: Then we have the following lexical rules. So in this grammar, our terminal symbols are the words. There is a special word for the symbols (such as N, PN, and Det) which occur in lexical rules: they are called preterminal symbols. This grammar is unambiguous. That is no string has two distinct parse trees. (Incidentally, this means that it is not a realistic grammar of English: all natural languages are highly ambiguous.) But it does display an interesting (and troublesome) phenomenon called local ambiguity. Consider the sentence ``The robber knew Vincent shot Marsellus''. This has a unique parse tree in this grammar. But now look at the first part of it: ``The robber knew Vincent''. This is also a sentence according to this grammar --- but not when considered as a part of ``The robber knew Vincent shot Marsellus''. This can be a problem for a parser. Locally we have something that looks like a sentence --- and a parser may prove that this part really is a sentence according to the grammar. But this information does not play a role in analyzing the larger sentence of which it is a part. |- Up -||Next >>|
A UUID (Universal Unique Identifier) is a 128-bit number used to uniquely identify some object or entity on the Internet. Depending on the specific mechanisms used, a UUID is either guaranteed to be different or is, at least, extremely likely to be different from any other UUID generated until 3400 A.D. The UUID relies upon a combination of components to ensure uniqueness. A guaranteed UUID contains a reference to the network address of the host that generated the UUID, a timestamp (a record of the precise time of a transaction), and a randomly generated component. Because the network address identifies a unique computer, and the timestamp is unique for each UUID generated from a particular host, those two components should sufficiently ensure uniqueness. However, the randomly generated element of the UUID is added as a protection against any unforseeable problem. A UUID is specified as part of the tModel data structure, which represents a service type (a generic representation of a registered service) in the UDDI (Universal Description, Discovery, and Integration) registry. This mechanism is used to discover Web services. UUIDs could be generated to refer to almost anything imaginable. Microsoft and some other software companies refer to GUIDs (global unique identifiers), a type of UUID used to refer to Component Object Module objects and other software components. The first UUIDs were created in the Network Computing System (NCS), and subsequently became a component of the Distributed Computing Environment (DCE) of the Open Software Foundation (OSF).
The FOSS Electronics Course emphasizes the use of knowledge and evidence to construct explanations for electrical energy and its use in technology. Students learn fundamental electrical circuitry and basic electronic principles. They make simple and complex circuits, quantify electrical interactions and properties (current, voltage, resistance) using a digital multimeter, and discover how different components affect circuits (resistors, diodes, LEDs, capacitors, transistors). They make and read schematics and construct solid-state devices. FOSS EXPECTS STUDENTS TO - Discover how to create complete circuits and how to identify series, parallel, and short circuits. - Discover how resistors influence the performance of lamps in electrical circuits and develop a model that explains what resistance is and how it might affect the flow of current in a circuit. - Explore, measure and manipulate one of the two main attributes of electricity, voltage, and discover how voltage can be influenced by components in a circuit. - Explore consumer products to discover the kinds and numbers of electronic components used in their design and consider the impact of technology on American life. - Discover the rules for predicting the total resistance imposed by multiple resistors places in series and/or parallel. - Discover the characteristics of capacitors, compare them to components with which they are familiar, and use them in circuits to perform new functions. - Understand the concept of electric current and use their understanding to solve circuit problems. - Discover the characteristics of transistors, compare them to components with which they are familiar, and use them in circuits to perform new functions. - Become familiar with and acquire vocabulary concerning these concepts: circuit, Ohm’s law, component, meter, digital, energy potential, current, resistance. - Exercise language, social studies, and math skills in the context of science. - Use scientific thinking processes to conduct investigations and build explanations: observing, communicating, comparing, organizing, relating, and inferring. For a description of each investigation in the Electronics Course and the correlations to the National Science Education Standards, download the Course Summary PDF. To view the PDF version of the course summary, you must have the Adobe Acrobat Reader plug-in. Acrobat Reader is available free from Adobe ©2014 UC Regents
Identify Threats and Human Uses In addition to identifying targets and goals, factors that are likely to affect the conservation and management of these targets are also identified. Threats and human use factors steer site selection to areas where the biological and physical targets are likely to be in better condition, where there are fewer human use conflicts, and where the overall suitability of conservation and management is higher (i.e. more financially feasible). For instance, an area that has been extensively developed or contains numerous pollution sources might be less suitable for biodiversity in general than an area that has been less developed. It may be more costly to achieve conservation in such areas as well. Examples of these factors include degraded water quality, shoreline hardening (seawalls, jetties), indicators of high use areas (docks, moorings, marinas), shipping lanes and oil rigs. It is important to transparently illustrate how each threat or human use affects the targets of concern. For example, seagrass beds are directly affected by coastal development and in particular the establishment of shoreline hardening. Managers and practitioners can decision support information to identify the relative distributions of both the target and the impact to that target. These individual factors are then compiled and weighted into a suitability index. It is often helpful during the Site Selection process to run separate scenarios with and without the inclusion of this index so that users can examine how this changes the results. Case Study: Carolinian Ecoregion In the Carolinian Ecoregion, spatial data were compiled for 10 types of suitability or “cost” factors and a suitability index was generated by tallying the total number of impacts within any given planning unit. The cost factors used were: - Mean population change, 1990-2000 - Housing density - Road density - Major port facilities - Major shipping lanes - Dredged shipping channels - Hardened shorelines - EPA Superfund sites - Permitted pollution discharge sites - Dredged material disposal site
FABRICATION OF OPTICAL FIBERS Basically, fiber manufacturers use two methods to fabricate multimode and single mode glass fibers. One method is vapor phase oxidation, and the other method is direct-melt process. In vapor phase oxidation, gaseous metal halide compounds, dopant material, and oxygen are oxidized (burned) to form a white silica powder (SiO2). Manufacturers call SiO2 the soot. Manufacturers deposit the soot on the surface of a glass substrate (mandrel) or inside a hollow tube by one of the following three methods: The soot forms the core and cladding material of the preform. The refractive index of each layer of soot is changed by varying the amount of dopant material being oxidized. Figures 3-8, 3-9, and 3-10 illustrate the different vapor phase oxidation preform preparation methods. Figure 3-8. - OVPO preform preparation. Figure 3-9. - IVPO preform preparation. Figure 3-10. - VAD preform preparation. During vapor phase oxidation, the mandrel or tube continuously moves from side to side and rotates while soot particles are deposited on the surface. This process forms cylindrical layers of soot on the surface of the mandrel or inside the hollow tube. This deposited material is transformed into a solid glass preform by heating the porous material (without melting). The solid preform is then drawn or pulled into an optical fiber by a process called fiber drawing. The fiber drawing process begins by feeding the glass preform into the drawing furnace. The drawing furnace softens the end of the preform to the melting point. Manufacturers then pull the softened preform into a thin glass filament (glass fiber). To protect the bare fiber from contaminants, manufacturers add an acrylate coating in the draw process. The coating protects the bare fiber from contaminants such as atmospheric dust and water vapor. Figure 3-11 illustrates the process of drawing an optical fiber from the preform. Figure 3-11. - Fiber drawing process. In the direct-melt process, multicomponent glass rods form the fiber structure. Rods of multicomponent glass combine in a molten state to form the fiber core and cladding. The double-crucible method is the most common direct-melt process. The double-crucible method combines the molten rods into a single preform using two concentric crucibles. Optical fibers are drawn from this molten glass using a similar fiber drawing process as in vapor phase oxidation. Figure 3-12 illustrates the double-crucible drawing process. Figure 3-12. - Double-crucible fiber drawing process. Q.24 What are the two methods used by fiber manufacturers to fabricate multimode and single mode glass fibers?
For those who live in Florida, Texas, California and other temperate locations, citrus trees offer a great variety of fruit that is nutritious and often very to grow. Still, citrus trees, like any other type of fruit tree, have their fair share of diseases with which to contend. Some of these will require the immediate destruction of the tree, and others can be dealt with by less severe measures. There are two main causes of citrus tree disease---bacteria and fungus. Among the bacteria that can affect the trees, citrus canker is the most feared. Fungi such as melanose, greasy spot and sooty mold can also cause potential problems, but most are aesthetic in nature. Root rot, another type of fungus, can put the entire tree, or at least its production, in jeopardy. In many cases, the type of disease can be identified by the marks it leaves on trees. Yellow halos on the fruit, twigs or leaves often indicate the appearance of canker. Melanose may appear as scabs on the fruit, particularly young grapefruit. Greasy spot and sooty mold leave spots and lesions on the leaves of citrus trees. Root rot is often identified by brownish patches on the tree's trunk as well as a liquid discharge. Many citrus tree diseases, whether fungi or bacteria, have the ability to move very fast on a tree and from tree to tree. This is especially true of citrus canker. Those who have multiple citrus trees may find an infection on one means many others may also have the same infection. This helps in the treatment strategy, as they can all be treated the same. In most cases, these citrus tree diseases are nothing more than parasites seeking a host to live off of. Although the end goal is not to kill or harm the tree, that may be what happens in the long run. Therefore, those who have trees with these afflictions, or suspect they may, action is important. In most cases, preventing fungus on citrus trees can be difficult. Unlike apples, pears and other northern fruit trees, there is less of a dormant season because of cold temperatures. Therefore, using a fungicide in the spring may not be effective. Controlling insects can help keep sooty mold at bay. Thus, the only thing the citrus owner can do is monitor and keep any outbreaks as isolated as possible. After an outbreak is noticed, the choices become more obvious. If it is a fungus, pruning and using a fungicide is often the best way to tackle the problem. If problem is citrus canker, it can be very hard to cure. In fact, some jurisdictions or states require immediate destruction of that tree and any citrus tree within a certain radius. For example, the rule is 1,900 feet in Florida. Further, Florida also restricts nurseries from selling trees located outside of 1,900 feet but within 3,800 feet of a canker discovery.
Primary Immune Deficiency The information provided is not intended to be a substitute for professional medical advice. A licensed healthcare professional should be consulted for diagnosis and treatment of any and all medical conditions. On this page: About Primary immune deficiency Primary immune deficiency (PI) is actually the name for a group of over 150 diseases1 that: - Are usually inherited - Are caused by errors in the genes of the cells that make up the immune system - Have a wide range of symptoms ranging from mild to severe People with primary immune deficiency diseases have immune systems that lack one or more types of immune tissues, proteins, or cells. The immune system protects the body from germs like bacteria and viruses. So, if part of your immune system is missing or not functioning correctly, you'll be more likely to get infections, you may take longer to recover, even with antibiotic treatment, and you may have recurring infections. Susceptibility to infection is one of the most common symptoms of primary immune deficiency. It can often be seen early in a child's life. However, signs of immune deficiency may also occur in older children, teenagers, or adults. Types of PI Primary immunodeficiency (PI) diseases differ in many ways. Some types of PI are characterized by low levels of antibodies. Others involve defects in T cells, B cells, granulocytes or the complement system. Because of these differences, individuals with different types of PI are susceptible to different types of diseases. Currently the World Health Organization lists over 150 different types of primary immunodeficiency. 1 Different therapies are available for different types of PI. And healthy living habits can improve outcomes as well. The most common types of PI include - X-Linked Agammaglobulinemia (XLA) - Common Variable Immunodeficiency (CVID)/ Hypogammaglobulinemia - Hyper-IgM Syndrome - Selective IgA Deficiency - IgG Subclass Deficiency - Severe Combined Immunodeficiency (SCID) - Wiskott-Aldrich Syndrome - DiGeorge Syndrome Intravenous immunoglobulin (IVIG) therapy2 There are a number of specific medical therapies that can help people diagnosed with primary immunodeficiencies (PI) lead healthier lives. One of the most common therapies is intravenous immunoglobulin, or IVIG. Intravenous immunoglobulin (IVIG) therapy is helpful to some people with primary immunodeficiency (PI) because it temporarily replaces infection-fighting antibodies that some PI patients are missing. This purified plasma treatment contains antibodies collected from the plasma of healthy donors and purified through a special process so that the therapy is safe and effective. Most of the antibodies are of the IgG class of antibodies, also called immunoglobulin G or gamma globulin. IVIG is given intravenously, which means through a needle directly into a vein. Your doctor will determine the correct dosage, based on a number of individual factors, including your weight, your condition, and how well the IVIG treats or prevents symptoms. IVIG can be administered in a hospital outpatient unit, infusion center, or your home. A typical infusion takes 2-4 hours, although some patients may require slower infusions to avoid side effects. IVIG replaces antibodies the body should be making, but does not help the patient's own immune system make more, so repeat doses are needed, usually every 3 to 4 weeks. Since primary immunodeficiency patients aren't "cured" by IVIG, they can still contract an infection, but infections have been shown to be less frequent and less severe. PI patients who rely on IVIG generally need infusions throughout their lives. 1. Geha R, Notarangelo L, Casanova JL, Conley ME, Chapel ME, Fischer A, Hammerstrom L, Nonoyama S, Ochs H, Puck J, Roifman C, Seger R, Wedgwood J. Primary immunodeficiency diseases: an update from the International Union of Immunological Societies Primary Immunodeficiency Diseases Classification Committee Meeting. Journal of Allergy and Clinical Immunology 2007; 120(4):776-794. 2. Patient & Family Handbook for Primary Immunedeficiency Diseases Produced by Immune Deficiency Foundation through a grant from Baxter. Fourth Edition. 2007.
Human Physiology/The female reproductive system ||Editing of this page by new or unregistered users is currently disabled due to vandalism. See the protection log for more details. If you cannot edit this page and you wish to make a change, you can request an edit, discuss changes on the discussion page, request unprotection, log in, or - 1 Introduction - 2 External Genitals - 3 Internal Genitals - 4 The Female Reproductive Cycle - 5 Ovarian and Uterine Cycles in the Nonpregnant Woman - 6 Sexual Reproduction - 7 Infertility - 8 Types of Birth Control - 9 Sexually Transmitted Diseases - 10 Diseases and Disorders of the Female Reproductive System - 11 Check Your Understanding - 12 Glossary - 13 References All living things reproduce. This is something that sets the living apart from non-living. Even though the reproductive system is essential to keeping a species alive, it is not essential to keeping an individual alive. This chapter describes the different parts of the female reproductive system: the organs involved in the process of reproduction, hormones that regulate a woman's body, the menstrual cycle, ovulation and pregnancy, the female's role in genetic division, birth control, sexually transmitted diseases and other diseases and disorders. Reproduction can be defined as the process by which an organism continues its species. In the human reproductive process, two kinds of sex cells ( gametes), are involved: the male gamete (sperm), and the female gamete (egg or ovum). These two gametes meet within the female's uterine tubes located one on each side of the upper pelvic cavity, and begin to create a new individual. The female needs a male to fertilize her egg; she then carries offspring through pregnancy and childbirth. Similarities between male and female reproductive systems The reproductive systems of the male and female have some basic similarities and some specialized differences. They are the same in that most of the reproductive organs of both sexes develop from similar embryonic tissue, meaning they are homologous. Both systems have gonads that produce (sperm and egg or ovum) and sex organs. And both systems experience maturation of their reproductive organs, which become functional during puberty as a result of the gonads secreting sex hormones. In short, this is a known list of sex organs that evolve from the same tissues in a human life. |Mullerian duct||Appendix testis||Fallopian tubes| |Mullerian duct||Prostatic utricle||Uterus, proximal| |Wolffian duct||Rete testis||Rete ovarii| |Mesonephric tubules||Efferent ducts||Epoophoron| |Wolffian duct||Epididymis||Gartner's duct| |Wolffian duct||Vas deferens| |Wolffian duct||Seminal vesicle| |Wolffian duct||Prostate||Skene's glands| |Urogenital sinus||Bladder, urethra||Bladder, urethra, distal| |Urogenital sinus||Bulbourethral gland||Bartholin's gland| |Genital swelling||Scrotum||Labia majora| |Urogenital folds||Distal urethra||Labia minora| |Bulb of penis||Vestibular bulbs| |Glans penis||Clitoral glans| |Crus of penis||Clitoral crura| Differences between male and female reproductive systems The differences between the female and male reproductive systems are based on the functions of each individual's role in the reproduction cycle. A male who is healthy, and sexually mature, continuously produces sperm. The development of women's "eggs" are arrested during fetal development. This means she is born with a predetermined number of oocytes and cannot produce new ones. At about 5 months gestation, the ovaries contain approximately six to seven million oogonia, which initiate meiosis. The oogonia produce primary oocytes that are arrested in prophase I of meiosis from the time of birth until puberty. After puberty, during each menstrual cycle, one or several oocytes resume meiosis and undergo their first meiotic division during ovulation. This results in the production of a secondary oocyte and one polar body. The meiotic division is arrested in metaphase II. Fertilization triggers completion of the second meiotic division and the result is one ovum and an additional polar body. The ovaries of a newborn baby girl contain about one million oocytes. This number declines to 400,000 to 500,000 by the time puberty is reached. On average, 500-1000 oocytes are ovulated during a woman's reproductive lifetime. When a young woman reaches puberty around age 10 to 13, a promary oocyte is discharged from one of the ovaries every 28 days. This continues until the woman reaches menopause, usually around the age of 50 years. Occytes are present at birth, and age as a woman ages. - Female Reproductive System - Produces eggs (ova) - Secretes sex hormones - Receives the male spermatazoa during - Protects and nourishes the fertilized egg until it is fully developed - Delivers fetus through birth canal - Provides nourishment to the baby through milk secreted by mammary glands in the breast The external female genitalia is referred to as vulva. It consists of the labia majora and labia minora (while these names translate as "large" and "small" lips, often the "minora" can protrude outside the "majora"), mons pubis, clitoris, opening of the urethra (meatus), vaginal vestibule, vestibular bulbs, vestibular glands. The term "vagina" is often improperly used as a generic term to refer to the vulva or female genitals, even though - strictly speaking - the vagina is a specific internal structure and the vulva is the exterior genitalia only. Calling the vulva the vagina is akin to calling the mouth the throat. The mons veneris, Latin for "mound of Venus" (Roman Goddess of love) is the soft mound at the front of the vulva (fatty tissue covering the pubic bone). It is also referred to as the mons pubis. The mons veneris protects the pubic bone and vulva from the impact of sexual intercourse. After puberty, it is covered with pubic hair, usually in a triangular shape. Heredity can play a role in the amount of pubic hair an individual grows. The labia majora are the outer "lips" of the vulva. They are pads of loose connective and adipose tissue, as well as some smooth muscle. The labia majora wrap around the vulva from the mons pubis to the perineum. The labia majora generally hides, partially or entirely, the other parts of the vulva. There is also a longitudinal separation called the pudendal cleft. These labia are usually covered with pubic hair. The color of the outside skin of the labia majora is usually close to the overall color of the individual, although there may be some variation. The inside skin is usually pink to light brown. They contain numerous sweat and oil glands. It has been suggested that the scent from these oils are sexually arousing. Medial to the labia majora are the labia minora. The labia minora are the inner lips of the vulva. They are thin stretches of tissue within the labia majora that fold and protect the vagina, urethra, and clitoris. The appearance of labia minora can vary widely, from tiny lips that hide between the labia majora to large lips that protrude. There is no pubic hair on the labia minora, but there are sebaceous glands. The two smaller lips of the labia minora come together longitudinally to form the prepuce, a fold that covers part of the clitoris. The labia minora protect the vaginal and urethral openings. Both the inner and outer labia are quite sensitive to touch and pressure. The clitoris, visible as the small white oval between the top of the labia minora and the clitoral hood, is a small body of spongy tissue that functions solely for sexual pleasure. Only the tip or glans of the clitoris shows externally, but the organ itself is elongated and branched into two forks, the crura, which extend downward along the rim of the vaginal opening toward the perineum. Thus the clitoris is much larger than most people think it is, about 4" long on average. The clitoral glans or external tip of the clitoris is protected by the prepuce, or clitoral hood, a covering of tissue similar to the foreskin of the male penis. However, unlike the penis, the clitoris does not contain any part of the urethra. During sexual excitement, the clitoris erects and extends, the hood retracts, making the clitoral glans more accessible. The size of the clitoris is variable between women. On some, the clitoral glans is very small; on others, it is large and the hood does not completely cover it. The opening to the urethra is just below the clitoris. Although it is not related to sex or reproduction, it is included in the vulva. The urethra is actually used for the passage of urine. The urethra is connected to the bladder. In females the urethra is 1.5 inches long, compared to males whose urethra is 8 inches long. Because the urethra is so close to the anus, women should always wipe themselves from front to back to avoid infecting the vagina and urethra with bacteria. This location issue is the reason for bladder infections being more common among females. The hymen is a thin fold of mucous membrane that separates the lumen of the vagina from the urethral sinus. Sometimes it may partially cover the vaginal orifice. The hymen is usually perforated during later fetal development. Because of the belief that first vaginal penetration would usually tear this membrane and cause bleeding, its "intactness" has been considered a guarantor of virginity. However, the hymen is a poor indicator of whether a woman has actually engaged in sexual intercourse because a normal hymen does not completely block the vaginal opening. The normal hymen is never actually "intact" since there is always an opening in it. Furthermore, there is not always bleeding at first vaginal penetration. The blood that is sometimes, but not always, observed after first penetration can be due to tearing of the hymen, but it can also be from injury to nearby tissues. A tear to the hymen, medically referred to as a "transection," can be seen in a small percentage of women or girls after first penetration. A transection is caused by penetrating trauma. Masturbation and tampon insertion can, but generally are not forceful enough to cause penetrating trauma to the hymen. Therefore, the appearance of the hymen is not a reliable indicator of virginity or chastity. The perineum is the short stretch of skin starting at the bottom of the vulva and extending to the anus. It is a diamond shaped area between the symphysis pubis and the coccyx. This area forms the floor of the pelvis and contains the external sex organs and the anal opening. It can be further divided into the urogenital triangle in front and the anal triangle in back. The perineum in some women may tear during the birth of an infant and this is apparently natural. Some physicians however, may cut the perineum preemptively on the grounds that the "tearing" may be more harmful than a precise cut by a scalpel. If a physician decides the cut is necessary, they will perform it. The cut is called an episiotomy. The vagina is a muscular, hollow tube that extends from the vaginal opening to the cervix of the uterus. It is situated between the urinary bladder and the rectum. It is about three to five inches long in a grown woman. The muscular wall allows the vagina to expand and contract. The muscular walls are lined with mucous membranes, which keep it protected and moist. A thin sheet of tissue with one or more holes in it, called the hymen, partially covers the opening of the vagina. The vagina receives sperm during sexual intercourse from the penis. The sperm that survive the acidic condition of the vagina continue on through to the fallopian tubes where fertilization may occur. The vagina is made up of three layers, an inner mucosal layer, a middle muscularis layer, and an outer fibrous layer. The inner layer is made of vaginal rugae that stretch and allow penetration to occur. These also help with stimulation of the penis. microscopically the vaginal rugae has glands that secrete an acidic mucus (pH of around 4.0.) that keeps bacterial growth down. The outer muscular layer is especially important with delivery of a fetus and placenta. - Purposes of the Vagina - Receives a male's erect penis and semen during sexual intercourse. - Pathway through a woman's body for the baby to take during childbirth. - Provides the route for the menstrual blood (menses) from the uterus, to leave the body. - May hold forms of birth control, such as a diaphragm, FemCap, Nuva Ring, or female condom. Pelvic inflammatory disease (PID) is a widespread infection that originates in the vagina and uterus and spreads to the uterine tubes, ovaries, and ultimately the pelvic peritoneum. This condition, which occurs in about 10% of women is usually caused by chlamydial or gonorrheal infection, other bacteria infecting the vagina may be involved as well. Signs and symptoms include tenderness of the lower abdomen, fever, and a vaginal discharge. Even a single episode of PID can cause infertility, due to scarring that blocks the uterine tubes. Therefore, patients are immediately given broad-spectrum antibiotics whenever PID is suspected. The cervix (from Latin "neck") is the lower, narrow portion of the uterus where it joins with the top end of the vagina. Where they join together forms an almost 90 degree curve. It is cylindrical or conical in shape and protrudes through the upper anterior vaginal wall. Approximately half its length is visible with appropriate medical equipment; the remainder lies above the vagina beyond view. It is occasionally called "cervix uteri", or "neck of the uterus". During menstruation, the cervix stretches open slightly to allow the endometrium to be shed. This stretching is believed to be part of the cramping pain that many women experience. Evidence for this is given by the fact that some women's cramps subside or disappear after their first vaginal birth because the cervical opening has widened. The portion projecting into the vagina is referred to as the portio vaginalis or ectocervix. On average, the ectocervix is three cm long and two and a half cm wide. It has a convex, elliptical surface and is divided into anterior and posterior lips. The ectocervix's opening is called the external os. The size and shape of the external os and the ectocervix varies widely with age, hormonal state, and whether the woman has had a vaginal birth. In women who have not had a vaginal birth the external os appears as a small, circular opening. In women who have had a vaginal birth, the ectocervix appears bulkier and the external os appears wider, more slit-like and gaping. The passageway between the external os and the uterine cavity is referred to as the endocervical canal. It varies widely in length and width, along with the cervix overall. Flattened anterior to posterior, the endocervical canal measures seven to eight mm at its widest in reproductive-aged women. The endocervical canal terminates at the internal os which is the opening of the cervix inside the uterine cavity. During childbirth, contractions of the uterus will dilate the cervix up to 10 cm in diameter to allow the child to pass through. During orgasm, the cervix convulses and the external os dilates. The uterus is shaped like an upside-down pear, with a thick lining and muscular walls. Located near the floor of the pelvic cavity, it is hollow to allow a blastocyte, or fertilized egg, to implant and grow. It also allows for the inner lining of the uterus to build up until a fertilized egg is implanted, or it is sloughed off during menses. The uterus contains some of the strongest muscles in the female body. These muscles are able to expand and contract to accommodate a growing fetus and then help push the baby out during labor. These muscles also contract rhythmically during an orgasm in a wave like action. It is thought that this is to help push or guide the sperm up the uterus to the fallopian tubes where fertilization may be possible. The uterus is only about three inches long and two inches wide, but during pregnancy it changes rapidly and dramatically. The top rim of the uterus is called the fundus and is a landmark for many doctors to track the progress of a pregnancy. The uterine cavity refers to the fundus of the uterus and the body of the uterus. Helping support the uterus are ligaments that attach from the body of the uterus to the pelvic wall and abdominal wall. During pregnancy the ligaments prolapse due to the growing uterus, but retract after childbirth. In some cases after menopause, they may lose elasticity and uterine prolapse may occur. This can be fixed with surgery. Some problems of the uterus include uterine fibroids, pelvic pain (including endometriosis, adenomyosis), pelvic relaxation (or prolapse), heavy or abnormal menstrual bleeding, and cancer. It is only after all alternative options have been considered that surgery is recommended in these cases. This surgery is called hysterectomy. Hysterectomy is the removal of the uterus, and may include the removal of one or both of the ovaries. Once performed it is irreversible. After a hysterectomy, many women begin a form of alternate hormone therapy due to the lack of ovaries and hormone production. At the upper corners of the uterus are the fallopian tubes. There are two fallopian tubes, also called the uterine tubes or the oviducts. Each fallopian tube attaches to a side of the uterus and connects to an ovary. They are positioned between the ligaments that support the uterus. The fallopian tubes are about four inches long and about as wide as a piece of spaghetti. Within each tube is a tiny passageway no wider than a sewing needle. At the other end of each fallopian tube is a fringed area that looks like a funnel. This fringed area, called the infundibulum, lies close to the ovary, but is not attached. The ovaries alternately release an egg. When an ovary does ovulate, or release an egg, it is swept into the lumen of the fallopian tube by the fimbriae. Once the egg is in the fallopian tube, tiny hairs in the tube's lining help push it down the narrow passageway toward the uterus. The oocyte, or developing egg cell, takes four to five days to travel down the length of the fallopian tube. If enough sperm are ejaculated during sexual intercourse and there is an oocyte in the fallopian tube, fertilization will occur. After fertilization occurs, the zygote, or fertilized egg, will continue down to the uterus and implant itself in the uterine wall where it will grow and develop. If a zygote doesn't move down to the uterus and implants itself in the fallopian tube, it is called a ectopic or tubal pregnancy. If this occurs, the pregnancy will need to be terminated to prevent permanent damage to the fallopian tube, possible hemorrhage and possible death of the mother. Mammary glands are the organs that produce milk for the sustenance of a baby. These exocrine glands are enlarged and modified sweat glands. The basic components of the mammary gland are the alveoli (hollow cavities, a few millimetres large) lined with milk-secreting epithelial cells and surrounded by myoepithelial cells. These alveoli join up to form groups known as lobules, and each lobule has a lactiferous duct that drains into openings in the nipple. The myoepithelial cells can contract, similar to muscle cells, and thereby push the milk from the alveoli through the lactiferous ducts towards the nipple, where it collects in widenings (sinuses) of the ducts. A suckling baby essentially squeezes the milk out of these sinuses. The development of mammary glands is controlled by hormones. The mammary glands exist in both sexes, but they are rudimentary until puberty when - in response to ovarian hormones - they begin to develop in the female. Estrogen promotes formation, while testosterone inhibits it. At the time of birth, the baby has lactiferous ducts but no alveoli. Little branching occurs before puberty when ovarian estrogens stimulate branching differentiation of the ducts into spherical masses of cells that will become alveoli. True secretory alveoli only develop in pregnancy, where rising levels of estrogen and progesterone cause further branching and differentiation of the duct cells, together with an increase in adipose tissue and a richer blood flow. Colostrum is secreted in late pregnancy and for the first few days after giving birth. True milk secretion (lactation) begins a few days later due to a reduction in circulating progesterone and the presence of the hormone prolactin. The suckling of the baby causes the release of the hormone oxytocin which stimulates contraction of the myoepithelial cells. The cells of mammary glands can easily be induced to grow and multiply by hormones. If this growth runs out of control, cancer results. Almost all instances of breast cancer originate in the lobules or ducts of the mammary glands. |STRUCTURE||LOCATION & DESCRIPTION||FUNCTION| |Breasts||Upper chest one on each side containing alveolar cells (milk production), myoepithelial cells (contract to expel milk), and duct walls (help with extraction of milk).||Lactation milk/nutrition for newborn.| |Cervix||The lower narrower portion of the uterus.||During childbirth, contractions of the uterus will dilate the cervix up to 10 cm in diameter to allow the child to pass through. During orgasm, the cervix convulses and the external os dilates| |Clitoris||Small erectile organ directly in front of the vestibule.||Sexual excitation, engorged with blood.| |Fallopian tubes||Extending upper part of the uterus on either side.||Egg transportation from ovary to uterus (fertilization usually takes place here).| |Hymen||Thin membrane that partially covers the vagina in young females.| |Labia majora||Outer skin folds that surround the entrance to the vagina.||Lubrication during mating.| |Labia minora||Inner skin folds that surround the entrance to the vagina.||Lubrication during mating.| |Mons||Mound of skin and underlying fatty tissue, central in lower pelvic region| |Ovaries (female gonads)||Pelvic region on either side of the uterus.||Provides an environment for maturation of oocyte. Synthesizes and secretes sex hormones (estrogen and progesterone).| |Perineum||Short stretch of skin starting at the bottom of the vulva and extending to the anus.| |Urethra||Pelvic cavity above bladder, tilted.||Passage of urine.| |Uterus||Center of pelvic cavity.||To house and nourish developing human.| |Vagina||Canal about 10-8 cm long going from the cervix to the outside of the body.||Receives penis during mating. Pathway through a womans body for the baby to take during childbirth. Provides the route for the menstrual blood (menses) from the uterus, to leave the body. May hold forms of birth control, such as an IUD, diaphragm, neva ring, or female condom| |Vulva||Surround entrance to the reproductive tract.(encompasses all external genitalia)| |Endometrium||The innermost layer of uterine wall.||Contains glands that secrete fluids that bathe the utrine lining.| |Myometrium||Smooth muscle in uterine wall.||Contracts to help expel the baby.| The Female Reproductive Cycle Towards the end of puberty, girls begin to release eggs as part of a monthly period called the female reproductive cycle, or menstrual cycle (menstrual referring to "monthly"). Approximately every 28 days, during ovulation, an ovary sends a tiny egg into one of the fallopian tubes. Unless the egg is fertilized by a sperm while in the fallopian in the two to three days following ovulation, the egg dries up and leaves the body about two weeks later through the vagina. This process is called menstruation. Blood and tissues from the inner lining of the uterus (the endometrium) combine to form the menstrual flow, which generally lasts from four to seven days. The first period is called menarche. During menstruation arteries that supply the lining of the uterus constrict and capillaries weaken. Blood spilling from the damaged vessels detaches layers of the lining, not all at once but in random patches. Endometrium mucus and blood descending from the uterus, through the liquid creates the menstruation flow. The reproductive cycle can be divided into an ovarian cycle and a uterine cycle (compare ovarian histology and uterine histology in the diagram on the right). During the uterine cycle, the endometrial lining of the uterus builds up under the influence of increasing levels of estrogen (labeled as estradiol in the image). Follicles develop, and within a few days one matures into an ovum, or egg. The ovary then releases this egg, at the time of ovulation. After ovulation the uterine lining enters a secretory phase, or the ovarian cycle, in preparation for implantation, under the influence of progesterone. Progesterone is produced by the corpus luteum (the follicle after ovulation) and enriches the uterus with a thick lining of blood vessels and capillaries so that it can sustain the growing fetus. If fertilization and implantation occur, the embryo produces Human Chorionic Gonadotropin (HCG), which maintains the corpus luteum and causes it to continue producing progesterone until the placenta can take over production of progesterone. Hence, progesterone is "pro gestational" and maintains the uterine lining during all of pregnancy. If fertilization and implantation do not occur the corpus luteum degenerates into a corpus albicans, and progesterone levels fall. This fall in progesterone levels cause the endometrium lining to break down and sluff off through the vagina. This is called menstruation, which marks the low point for estrogen activity and is the starting point of a new cycle. Common usage refers to menstruation and menses as a period. This bleeding serves as a sign that a woman has not become pregnant. However, this cannot be taken as certainty, as sometimes there is some bleeding in early pregnancy. During the reproductive years, failure to menstruate may provide the first indication to a woman that she may have become pregnant. Menstruation forms a normal part of a natural cyclic process occurring in healthy women between puberty and the end of the reproductive years. The onset of menstruation, known as menarche, occurs at an average age of 12, but is normal anywhere between 8 and 16. Factors such as heredity, diet, and overall health can accelerate or delay the onset of menarche. Signs of ovulation The female body produces outward signs that can be easily recognized at the time of ovulation. The two main signs are thinning of the cervical mucus and a slight change in body temperature. Thinning of the Cervical Mucus After menstruation and right before ovulation, a woman will experience an increase of cervical mucus. At first, it will be thick and yellowish in color and will not be very plentiful. Leading up to ovulation, it will become thinner and clearer. On or around the day of ovulation, the cervical mucus will be very thin, clear and stretchy. It can be compared to the consistency of egg whites. This appearance is known as 'spinnbarkeit'. A woman can also tell the time of ovulation by taking her basal body temperature daily. This is a temperature taken with a very sensitive thermometer first thing in the morning before the woman gets out of bed. The temperature is then tracked to show changes. In the uterine cycle, a normal temperature will be around 97.0 – 98.0. The day of ovulation the temperature spikes down, usually into the 96.0 – 97.0 range and then the next morning it will spike up to normal of around 98.6 and stay in that range until menstruation begins. Both of these methods are used for conception and contraception. They are more efficient in conception due to the fact that sperm can live for two to three days inside of the fallopian tubes. A woman could be off by a couple of days in her calculations and still become pregnant. Menopause is the physiological cessation of menstrual cycles associated with advancing age. Menopause is sometimes referred to as "the change of life" or climacteric. Menopause occurs as the ovaries stop producing estrogen, causing the reproductive system to gradually shut down. As the body adapts to the changing levels of natural hormones, vasomotor symptoms such as hot flashes and palpitations, psychological symptoms such as increased depression, anxiety, irritability, mood swings and lack of concentration, and atrophic symptoms such as vaginal dryness and urgency of urination appear. Together with these symptoms, the woman may also have increasingly scanty and erratic menstrual periods. Technically, menopause refers to the cessation of menses; the gradual process through which this occurs, which typically takes a year but may last as little as six months or more than five years, is known as climacteric. A natural or physiological menopause is that which occurs as a part of a woman's normal aging process. However, menopause can be surgically induced by such procedures as hysterectomy. The average onset of menopause is 50.5 years, but some women enter menopause at a younger age, especially if they have suffered from cancer or another serious illness and undergone chemotherapy. Premature menopause is defined as menopause occurring before the age of 40, and occurs in 1% of women. Other causes of premature menopause include autoimmune disorders, thyroid disease, and diabetes mellitus. Premature menopause is diagnosed by measuring the levels of follicle stimulating hormone (FSH) and luteinizing hormone (LH). The levels of these hormones will be higher if menopause has occurred. Rates of premature menopause have been found to be significantly higher in both fraternal and identical twins; approximately 5% of twins reach menopause before the age of 40. The reasons for this are not completely understood. Post-menopausal women are at increased risk of osteoporosis. Perimenopause refers to the time preceding menopause, during which the production of hormones such as estrogen and progesterone diminish and become more irregular. During this period fertility diminishes. Menopause is arbitrarily defined as a minimum of twelve months without menstruation. Perimenopause can begin as early as age 35, although it usually begins much later. It can last for a few months or for several years. The duration of perimenopause cannot be predicted in advance. Premenstrual Syndrome (PMS) It is common for women to experience some discomfort in the days leading up to their periods. PMS usually is at its worst the seven days before a period starts and can continue through the end of the period. PMS includes both physical and emotional symptoms: acne, bloating, fatigue, backaches, sore breasts, headaches, constipation, diarrhea, food cravings, depression, irritability, difficulty concentrating or handling stress. Ovarian and Uterine Cycles in the Nonpregnant Woman |Ovarian Cycle||Events||Uterine Cycle||Events| |Follicular phase - Days 1-13||FSH secretion begins.||Menstruation - Days 2-5||Endometrium breaks down.| |Follicle maturation occurs.||Proliferative phase - Days 6-13||Endometrium rebuilds.| |Estrogen secretion is prominent.| |Ovulation - Day 14*||LH spike occurs.| |Luteal phase - Days 15-28||LH secretion continues.||Secretory phase - Days 15-28||Endometrial thickens, and glands are secretory.| |Corpus luteum forms.| |Progesterone secretion is prominent.| (*)Assuming a 28 day cycle. There are two phases of the ovarian cycle the follicular phase and the luteal phase. In the follicular phase about 10-25 follicles are taken from preantral or early antrial follicles to develop further. Seven days later the dominant follicle is selected to develop to full maturity. This is the pre-cursor for ovulation. Follicles themselves secrete FSH and estrogen, and these two hormones stimulate follicular growth and development. Ovulation marks the beginning of the luteal phase. This is started by the wall of the Graffian follicle to rupture and cause a flow of antral fluid that will carry the oocyte to the ovary's surface. The ruptured follicle is then turned into a gland (corpus luteum). Which secretes estrogens and progesterone. This is all triggered by and abrupt change in plasma LH levels. After ovulation the released oocyte enters the uterine tube, where it will be either fertilized or discarded. The uterine cycle operates in sync with the ovarian cycle and is divided into three phases. The first phase in the menstrual phase. It is named the menstrual phase because in corresponds with the shedding the the uterine lining or more commonly called menstruation. The corpus luteum degenerates causing plasma estrogen and progesterone levels to decrease and in turn causes menstruation. Blood vessels in the outer most layer of the endometrium constrict and decrease blood flow to the tissues killing these tissues. After the tissues die they start to separate from the underlying endometrail tissues. Eventually the dead tissue is shed. This shedding of the tissues ruptures blood vessels and causes bleeding. Now we have the proliferative phase. During this phase the uterus renews itself and prepares for pregnancy. The endomitrial tissue that is left after menstruation begins to grow. The endometrial glands grow and enlarge causing more blood vessels. The cervical canal has glands that secrete a thin mucous that helps deposited sperm. Estrogen promotes uterine changes in this phase. The last phase is the secretory phase. This is where the endometrium is transformed to make it the best environment for implantation and subsequent housing and nourishment of the developing embryo. By doing this the endometrium will do things like have an enriched blood supply, begin to secrete fluids rich in glycogen, and even form a plug at the end of the cervical canal so that microorganisms can not enter. These changes in the uterus are caused by progesterone, due to the corpus luteum. At the end of the secretory phase the corpus luteum degenerates, and progesterone levels fall. This will trigger menstruation. Sexual reproduction is a type of reproduction that results in increasing genetic diversity of the offspring. In sexual reproduction, genes from two individuals are combined in random ways with each new generation. Sex hormones released into the body by the endocrine system signal the body when it is time to start puberty. The female and male reproductive systems are the only systems so vastly different that each sex has their own different organs. All other systems have "unisex" organs. Reproduction is characterized by two processes. The first, meiosis, involves the halving of the 46 of chromosomes. The second process, fertilization, leads the fusion of two gametes and the restoration of the original number of chromosomes: 23 chromosomes from the paternal side and 23 from the maternal side. During meiosis, the chromosomes of each pair usually cross over to achieve genetic recombination. Sexual reproduction cannot happen without the sexual organs called gonads. Both sexes have gonads: in females, the gonads are the ovaries. The female gonads produce female gametes (eggs); the male gonads produce male gametes (sperm). After an egg is fertilized by the sperm, the fertilized egg is called the zygote. The fertilization usually occurs in the oviducts, but can happen in the uterus itself. The zygote then implants itself in the wall of the uterus, where it begins the processes of embryogenesis and morphogenesis. The womens body carries out this process of reproduction for 40 weeks, until delivery of the fetus from the uterus through the vagina (birth canal). Even after birth, the female continues with the reproduction process by supplying the milk to nourish the infant. Infertility is the inability to naturally conceive a child or the inability to carry a pregnancy to term. There are many reasons why a couple may not be able to conceive without medical assistance. Infertility affects approximately 15% of couples. Roughly 40% of cases involve a male contribution or factor, 40% involve a female factor, and the remaining 20% involve both sexes. Healthy couples in their mid-20s having regular sex have a one-in-four chance of getting pregnant in any given month. This is called "Fecundity". Primary vs. secondary According to the American Society for Reproductive Medicine, infertility affects about 6.1 million people in the United States, equivalent to 10% of the reproductive age population. Female infertility accounts for one third of infertility cases, male infertility for another third, combined male and female infertility for another 15%, and the remainder of cases are "unexplained. "Secondary infertility" is difficulty conceiving after already having conceived and carried a normal pregnancy. Apart from various medical conditions (e.g. hormonal), this may come as a result of age and stress felt to provide a sibling for their first child. Technically, secondary infertility is not present if there has been a change of partners. Factors of Infertility Factors relating to female infertility are: - General factors - Diabetes mellitus,thyroid disorders,adrenal disease - Significant liver,kidney disease - Psychological factors - Hypothalamic-pituitary factors: - Kallmann syndrome - Hypothalamic dysfunction - Ovarian factors - Polycystic ovary syndrome - Diminished ovarian reserve - Luteal dysfunction - Premature menopause - Gonadal dysgenesis (Turner syndrome) - Ovarian neoplasm - Tubal/peritoneal factors - Pelvic adhesions - Pelvic inflammatory disease(PID, usually due to chlamydia) - Tubal occlusion - Uterine factors - Uterine malformations - Uterine fibroids (leiomyoma) - Asherman's Syndrome - Cervical factors - Cervical stenosis - Antisperm antibodies - Insufficient cervical mucus (for the travel and survival of sperm) - Vaginal factors - Vaginal obstruction - Genetic factors - Various intersexuality|intersexed conditions, such as androgen insensitivity syndrome In some cases, both the man and woman may be infertile or sub-fertile, and the couple's infertility arises from the combination of these factors. In other cases, the cause is suspected to be immunological or genetic; it may be that each partner is independently fertile but the couple cannot conceive together without assistance. In about 15% of cases of infertility, investigation will show no abnormalities. In these cases abnormalities are likely to be present but not detected by current methods. Possible problems could be that the egg is not released at the optimum time for fertilization, that it may not enter the fallopian tube, sperm may not be able to reach the egg, fertilization may fail to occur, transport of the zygote may be disturbed, or implantation fails. It is increasingly recognized that egg quality is of critical importance. Diagnosis of Infertility Diagnosis of infertility begins with a medical history and physical exam. The healthcare provider may order tests, including the following: - an endometrial biopsy, which tests the lining of the uterus - hormone testing, to measure levels of female hormones - laparoscopy, which allows the provider to see the pelvic organs - ovulation testing, which detects the release of an egg from the ovary - Pap smear, to check for signs of infection - pelvic exam, to look for abnormalities or infection - a postcoital test, which is done after sex to check for problems with secretions - special X-ray tests - Fertility medication which stimulates the ovaries to "ripen" and release eggs (e.g. Clomifene|clomifene citrate, which stimulates ovulation) - Surgery to restore potency of obstructed fallopian tubes (tuboplasty) - Donor insemination which involves the woman being artificially inseminated or artificially inseminated with donor sperm. - In vitro fertilization (IVF) in which eggs are removed from the woman, fertilized and then placed in the woman's uterus, bypassing the fallopian tubes. Variations on IVF include: - Use of donor eggs and/or sperm in IVF. This happens when a couple's eggs and/or sperm are unusable, or to avoid passing on a genetic disease. - Intracytoplasmic sperm injection (ICSI) in which a single sperm is injected directly into an egg; the fertilized egg is then placed in the woman's uterus as in IVF. - Zygote intrafallopian transfer(ZIFT) in which eggs are removed from the woman, fertilized and then placed in the woman's fallopian tubes rather than the uterus. - Gamete intrafallopian transfer(GIFT) in which eggs are removed from the woman, and placed in one of the fallopian tubes, along with the man's sperm. This allows fertilization to take place inside the woman's body. - Other assisted reproductive technology (ART): - Assisted hatching - Fertility preservation - Freezing (cryopreservation) of sperm, eggs, & reproductive tissue - Frozen embryo transfer (FET) - Alternative and complimentary treatments - Acupuncture Recent controlled trials published in Fertility and Sterility have shown acupuncture to increase the success rate of IVF by as much as 60%. Acupuncture was also reported to be effective in the treatment of female anovular infertility, World Health Organization, Acupuncture: Review and Analysis of Reports on Controlled Trials (2002). - Diet and supplements - Healthy lifestyle Types of Birth Control Birth control is a regimen of one or more actions, devices, or medications followed in order to deliberately prevent or reduce the likelihood of a woman becoming pregnant. Methods and intentions typically termed birth control may be considered a pivotal ingredient to family planning. Mechanisms which are intended to reduce the likelihood of the fertilization of an ovum by a sperm may more specifically be referred to as contraception. Contraception differs from abortion in that the former prevents fertilization, while the latter terminates an already established pregnancy. Methods of birth control (e.g. the pill, IUDs, implants, patches, injections, vaginal ring and some others) which may prevent the implantation of an embryo if fertilization occurs are medically considered to be contraception. It is advised to talk with a doctor before choosing a contraceptive. If you have genetics problems or blood conditions, such as factor V leiden, certain contraceptives can be deadly. |Abstinence||Refrain from sexual intercourse||No sperm in vagina||100%||None| |Rhythm Method||Intercourse is avoided for about an 8-day span every month in middle of her cycle, from about five days before ovulation to three days after ovulation.||fertilization is only possible during 8-day span in middle of menstrual cycle||70-80%||None| |Withdrawal||The man withdraws his penis from the vagina at just the right moment before ejaculation.||sperm are unable to enter vagina if male penis is removed at the right time||70-80%||None| |Tubal Ligation (Vasectomy)||Oviducts are cut and tied||No eggs in oviduct||Almost 99%||About 75% Irreversible| |Hormonal IUD (intrauterine device)||Flexible, plastic coil inserted by physician||Releases small amounts of estrogen. In most cases, stops egg from developing and being released, but can also operate by killing a fertilized egg by preventing its implantation||About 99%||May cause infections, uterine perforation| |Oral Contraceptive||Hormone medication taken daily||Stops release of FSH and LH, but can also operate by killing a fertilized egg by preventing its implantation||More than 90%||Blood clots, especially in smokers| |Contraceptive Implants||Tubes of progesterone implanted under the skin||Stops release of FSH and LH, but can also operate by killing a fertilized egg by preventing its implantation||More than 90%||None known| |Contraceptive Injections||Injections of hormones||Stops release of FSH and LH, but can also operate by killing a fertilized egg by preventing its implantation||About 99%||Possible osteoporosis| |Diaphragm||Latex cup inserted into vagina to cover cervix before intercourse||Blocks entrance of sperm into uterus||With spermicide, about 90%||Latex or spermicide allergy| |Cervical Cap||Latex cup held by suction over cervix||Delivers spermicide near cervix||Almost 85%||UTI, latex or spermicide allergy| |Female Condom||Polyurethane liner fitted inside vagina||Blocks entrance of sperm into uterus and prevents STD’s||Almost 85%||None| |Male Condom||soft sheath, made of latex or animal membrane, encloses penis, trapping ejaculated sperm||Blocks entrance of sperm into vagina and prevents STD's||90%||None| |Jellies, Cream, Foams||Spermicidal products inserted before intercourse||Kills large number of sperm||About 75%||UTI, allergy to spermicides| |Natural Family Planning||Keep record of ovulation using various methods||Avoid sexual intercourse near ovulation||About 70%||None known| |Douche||Vagina cleansed after intercourse||Washes out sperm||Less than 70%||None known| |Plan B Pill||Pill taken after intercourse||Prevents release of egg, fertilization of egg, but can also operate by killing a fertilized egg by preventing its implantation||About 89%||Same as oral contraceptive| Sexually Transmitted Diseases Sexually transmitted diseases (STDs) are diseases or infections likely to be transmitted by sexual contact: vaginal intercourse, oral sex, and/or anal sex. Many STDs are (more easily) transmitted through the mucous membranes of the penis, vulva, and (less often) the mouth. The visible membrane covering the head of the penis is a mucous membrane, though, for those who are circumcised it is usually dry and produces no mucus (similar to the lips of the mouth). Mucous membranes differ from skin in that they allow certain pathogens (viruses or bacteria) into the body (more easily). The probability of transmitting infections through sex is far greater than by more casual means of transmission, such as non-sexual contact—touching, sharing cutlery, and shaking hands. Although mucous membranes exist in the mouth as well as in the genitals, many STDs are more likely to be transmitted through oral sex than through deep kissing. Many infections that are easily transmitted from the mouth to the genitals or from the genitals to the mouth, are much harder to transmit from one mouth to another. With HIV, genital fluids happen to contain a great deal more of the pathogen than saliva. Some infections labeled as STDs can be transmitted by direct skin contact. Herpes simplex and HPV are both examples. Depending on the STD, a person who has the disease but has no symptoms may or may not be able to spread the infection. For example, a person is much more likely to spread herpes infection when blisters are present than when they are absent. However, a person can spread HIV infection at any time, even if he/she has not developed symptoms of AIDS. All sexual behaviors that involve contact with the bodily fluids of another person should be considered to hold some risk of transmission of sexually transmitted diseases. Most attention has focused on controlling HIV, which causes AIDS, but each STD presents a different situation. As may be noted from the name, sexually transmitted diseases are transmitted from one person to another by certain sexual activities rather than being actually caused by those sexual activities. Bacteria, fungi, protozoa or viruses are still the causative agents. It is not possible to catch any sexually transmitted disease from a sexual activity with a person who is not carrying a disease; conversely, a person who has an STD received it from contact (sexual or otherwise) with someone who is infected. Although the likelihood of transmitting diseases by sexual activities varies a great deal, in general, all sexual activities between two (or more) people should be considered as being a two-way route for the transmission of STDs (i.e. "giving" or "receiving" are both risky). Prevention of Sexually Transmitted Diseases Although healthcare professionals suggest that safer sex, such as the use of condoms, as the most reliable way of decreasing the risk of contracting sexually transmitted diseases during sexual activity, safer sex should by no means be considered an absolute safeguard. The transfer of and exposure to bodily fluids, such as blood transfusions and other blood products, sharing injection needles, needle-stick injuries (when medical staff are inadvertently jabbed or pricked with needles during medical procedures), sharing tattoo needles, and childbirth are all avenues of transmission. These means put certain groups, such as doctors, haemophiliacs and drug users, particularly at risk. Human Papillomavirus (HPV) There are over 100 types of this virus which is often asymptomatic. Nearly 3 out of 4 Americans between ages 15 and 49 have been infected. It can be contracted through one partner and remain dormant allowing it to be transmitted to another. Some types can cause cervical cancer. Genital HPV infection is a sexually transmitted disease that is caused by human papillomavirus. Human papillomavirus is the name of a group of viruses that includes more than 100 different strains. More than 30 of these are sexually transmitted and they can infect the genital area of men and women. Approximately 20 million people are currently infected with HPV and at least 50% of sexually active men and women will acquire HPV at some point in their lives. By age 50 at least 80% of women will have acquired HPV and about 6.2 million Americans get a new HPV infection each year. Most people who have HPV don't know that they are infected. The virus lives in the skin or mucous membranes and usually causes no symptoms. Commonly some people get visible genital warts or have pre-cancerous changes in the cervix, vulva, anus, or penis. Very rarely, HPV results in anal or genital cancers. Genital warts usually appear soft, moist, pink, or flesh colored swellings. They can be raised, flat, single, or multiple, small or large and sometimes cauliflower shaped. Warts may not appear for weeks or months or not at all and the only way to diagnose them is by visible inspection. Most women are diagnosed with HPV on the basis of abnormal pap tests and there are no tests available for men. There is no cure for HPV. The surest way to eliminate risk for HPV is to refrain from any genital contact with another individual. For those who choose to be sexually active, a long term monogamous relationship with an uninfected partner is the strategy most likely to prevent future HPV infections.The next best way to help reduce risk is using a condom but the effectiveness is unknown. What is the connection between HPV and cervical cancer? All types of HPV cause mild pap test abnormalities which do not have serious consequences. Approximately 10 of the 30 identified HPV types can lead to development of cervical cancer. Research as shown that for most women, 90% cervical HPV infection becomes undetectable within two years. Although only a small proportion of women have persistent infection, persistent infection with the high risk types of HPV is the main risk factor for cervical cancer. A pap test can detect pre-cancerous and cancerous cells on the cervix. Regular pap testing and careful medical follow up, with treatment if necessary, can help ensure that pre-cancerous changes in the cervix caused by HPV infection do not develop into life threatening cervical cancer. The pap test used in the U.S. cervical cancer screening programs is responsible for greatly reducing deaths from cervical cancer. Diseases and Disorders of the Female Reproductive System Women are commonly dealing with many different diseases and disorders that pertain to the reproductive system. Here are some of the most common: - Vulvovaginitis (pronounced:vul-vo-vah-juh-ni-tus) is an inflammation of the vulva and vagina. It may be caused by irritating substances such as laundry soap, bubble baths or poor hygiene such as wiping from back to front. Symptoms include redness and itching in these areas and sometimes vaginal discharge. It can also be caused by an overgrowth of candida, a fungus normally present in the vagina. - Nonmenstrual vaginal bleeding is most commonly due to the presence of a foreign body in the vagina. It may also be due to urethral prolapse, a condition in which the mucous membranes of the urethra protrude into the vagina and forms a tiny, donut shaped mass of tissue that bleeds easily. It can also be due to a straddle injury or vaginal trauma from sexual abuse. - Ectopic Pregnancy occurs when a fertilized egg or zygote doesn't travel into the uterus, but instead grows rapidly in the fallopian tube. Women with this condition can develop severe abdominal pain and should see a doctor because surgery may be necessary. - Ovarian tumors,although rare, can occur. Women with ovarian tumors may have abdominal pain and masses that can be felt in the abdomen. Surgery may be needed to remove the tumor. - Ovarian cysts are noncancerous sacs filled with fluid or semi-solid material. Although they are common and generally harmless, they can become a problem if they grow very large. Large cysts may push on surrounding organs, causing abdominal pain. In most cases, cysts will pass or disappear on their own and treatment is not necessary. If the cysts are painful and occur frequently, a doctor may prescribe birth control pills to alter their growth and occurrences. Surgery is also an option if they need to be removed. - Polycystic ovary syndrome is a hormone disorder in which too many hormones are produced by the ovaries. This condition causes the ovaries to become enlarged and develop many fluid filled sacs or cysts. It often first appears during the teen years. Depending on the type and the severity of the condition, it may be treated with drugs to regulate hormone balance and menstruation. - Trichomonas vaginalis inflammatory condition of the vagina usually a bacterial infection also called vaginosis. - Dysmenorrhea is painful periods. - Menorrhagia is when a woman has very heavy periods with excess bleeding. - Oligomenorrhea is when a woman misses or has infrequent periods, even though she has been menstruating for a while and is not pregnant. - Amenorrhea is when a girl has not started her period by the time she is 16 years old or 3 years after puberty has started, has not developed signs of puberty by 14, or has had normal periods but has stopped menstruating for some reasons other than pregnancy. - Toxic shock syndrome is caused by toxins released into the body during a type of bacterial infection that is more likely to develop if a tampon is left in too long. It can produce high fever, diarrhea, vomiting, and shock. - Candidasis symptoms of yeast infections include itching, burning and discharge. Yeast organisms are always present in all people, but are usually prevented from "overgrowth" (uncontrolled multiplication resulting in symptoms) by naturally occurring microorganisms. At least three quarters of all women will experience candidiasis at some point in their lives. The Candida albicans organism is found in the vaginas of almost all women and normally causes no problems. However, when it gets out of balance with the other "normal flora," such as lactobacilli (which can also be harmed by using douches), an overgrowth of yeast can result in noticeable symptoms. Pregnancy, the use of oral contraceptives, engaging in vaginal sex after anal sex in an unhygienic manner, and using lubricants containing glycerin have been found to be causally related to yeast infections. Diabetes mellitus and the use of antibiotics are also linked to an increased incidence of yeast infections. Candidiasis can be sexually transmitted between partners. Diet has been found to be the cause in some animals. Hormone Replacement Therapy and Infertility Treatment may be factors. There are also cancer's of the female reproductive system, such as: - Cervical cancer - Ovarian cancer - Uterine cancer - Breast cancer Endometriosis is the most common gynecological diseases, affecting more than 5.5 million women in North America alone! The two most common symptoms are pain and infertility. In this disease a specialized type of tissue that normally lines the inside of the uterus,(the endometrium) becomes implanted outside the uterus, most commonly on the fallopian tubes, ovaries, or the tissue lining the pelvis. During the menstrual cycle, hormones signal the lining of the uterus to thicken to prepare for possible pregnancy. If a pregnancy doesn't occur, the hormone levels decrease, causing the thickened lining to shed. When endometrial tissue is located in other parts it continues to act in it's normal way: It thickens, breaks down and bleeds each month as the hormone levels rise and fall. However, because there's nowhere for the blood from this mislocated tissue to exit the body, it becomes trapped and surrounding tissue becomes irritated. Trapped blood may lead to growth of cysts. Cysts in turn may form scar tissue and adhesions. This causes pain in the area of the misplaced tissue, usually the pelvis. Endometriosis can cause fertility problems. In fact, scars and adhesions on the ovaries or fallopian tubes can prevent pregnancy. Endometriosis can be mild, moderate or severe and tends to get worse over time without treatment. The most common symptoms are: - Painful periods Pelvic pain and severe cramping, intense back pain and abdominal pain. - Pain at other times Women may experience pelvic pain during ovulation, sharp deep pain in pelvis during intercourse, or pain during bowel movements or urination. - Excessive bleeding Heavy periods or bleeding between periods. - Infertility Approximately 30-40% of women The cause of endometriosis remains mysterious. Scientists are studying the roles that hormones and the immune system play in this condition. One theory holds that menstrual blood containing endometrial cells flows back through the fallopian tubes, takes root and grows. Another hypothesis proposes that the bloodstream carries endometrial cells to other sites in the body. Still another theory speculates that a predisposition toward endometriosis may be carried in the genes of certain families. Other researchers believe that certain cells present within the abdomen in some women retain their ability to specialize into endometrial cells. These same cells were responsible for the growth of the woman's reproductive organs when she was an embryo. It is believed that genetic or environmental influences in later life allow these cells to give rise to endometrial tissue outside the uterus. Experts estimate that up to one in ten American women of childbearing age have endometriosis. There is some thinking that previous damage to cells that line the pelvis can lead to endometriosis. There are several ways to diagnose endometriosis: - Pelvic exam - Laparoscopy Usually used, most correct diagnosis - Blood test Endometriosis can be treated with: - Pain medication - Hormone therapy - Oral contraceptives - Gonadotropin-releasing hormone(Gn-Rh)agonists and antagonists - Conservative surgery which removes endometrial growths. Check Your Understanding - Answers for these questions can be found here 1. In homology, the ___________ in the female is equal to the penis in the male - A) labia majora - B) clitoral hood - C) clitoris - D) labia minora - E) none of the above 2. This contains some of the strongest muscles in the human body - A) uterus - B) clitoris - C) cervix - D) labia majora 3. This protects the vaginal and urethral openings - A) labia majora - B) labia minora - C) clitoris - D) urethra 4. Sally has noticed that her cervical mucus has changed and now resembles egg whites- from this Sally could assume - A) her period will begin soon - B) nothing, this is a normal occurrence - C) she has a yeast infection - D) she is ovulating 5. Debbie recently went to the OBGYN and was diagnosed with PCOD (polycystic ovary syndrome) because of this she has - A) nothing, its normal in women - B) antisperm antibodies - C) an overproduction of LH - D) leaking of milk from her mammary glands - E) problems becoming pregnant 6. Angie went to the doctor because she has had pain in her leg recently- this could be caused by - A) ovulation pain - B) her period that will be starting tomorrow - C) premenstrual syndrome - D) a blood clot resulting from her birth control pill 7. Sue recently started her period and has noticed that they are very heavy and painful, and that they are inconsistent in their timing. One explanation could be - A) endometriosis - B) ovarian cancer - C) candidasis - D) toxic shock syndrome - E) amenorrhea 8. Mary is getting married and is not ready to become a mother- she chooses this birth control because of its high effectiveness - A) natural family planning - B) a diaphragm - C) contraceptive injections - D) a spermicide foam 9. The release of LH in woman causes - A) menstration - B) ovulation - C) increase of endometrial lining - D) decrease of endometrial lining - E) nothing LH only does something in the male reproductive system 10. When the ovaries stop producing estrogen, this occurs - A) ovulation - B) implantation - C) premenstrual syndrome - D) menopause 11. Infertility affects what percentage of couples? - A) 5% - B) 10% - C) 15% - D) 20% 12. What is the only 100% effective form of birth control? - A) Tubal ligation - B) IUD - C) Natural family planning - D) Abstinence Adhesions: Abnormal tissue that binds organs together Alveoli: Basic components of the mammary glands; lined with milk-secreting epithelial cells Birth Control: regimen of one or more actions, devices, or medications followed in order to deliberately prevent or reduce the likelihood of a woman becoming pregnant Cervical Mucus: Mucus secreted by the cervix, near ovulation it helps to lower the acidity of the vagina Cervix: Lower, narrow portion of the uterus where it joins with the top of the vagina Clitoris: Small body of spongy tissue that functions solely for sexual pleasure Chromosomes: Structures in the nucleus that contain the genes for genetic expression Ectocervix: Portion of the cervix projecting into vagina Endocervical Canal: Passageway between the external os and the uterine cavity Endometrium: The inner lining of the uterus Fallopian Tubes: Located at the upper end of the vagina, passage way for the egg from the ovary Factor V Leiden: This is the name given to a variant of human factor V that causes a hypercoagulability disorder. In this disorder the Leiden variant of factor V, cannot be inactivated by activated protein C. Factor V Leiden is the most common hereditary hypercoagulability disorder amongst Eurasians. It is named after the city Leiden (The Netherlands), where it was first identified in 1994 by Prof R. Bertina et al. Gamete: A haploid sex cell; either an egg cell or a sperm cell Gene: That portion of the DNA of a chromosome containing the information needed to synthesize a particular protein molecule Gonad: A reproductive organ, testis or ovary that produces gametes and sex hormones Hormone: A chemical substance produced in an endocrine gland and secreted into the bloodstream that acts on target cells to produce a specific effect Hymen: Thin fold of mucous membrane that separates the lumen of the vagina from the urethral sinus Infertility: Inability to naturally conceive a child or the inability to carry a pregnancy to term Labia Majora: Outer "lips" of the vulva, made of loose connective tissue and adipose tissue with some smooth muscle Labia Minora: Inner lips of the vulva, folds and protects the vagina, urethra and clitoris Mammary Glands: Organs that produce milk for the sustenance of a baby Meiosis: A specialized type of cell division by which gametes, or haploid sex cells, are formed Menarche: The first menstrual discharge; occurs normally between the ages of 9 and 17 Menopause: The period marked by the cessation of menstrual periods in the human female Menstrual Cycle: The rhythmic female reproductive cycle characterized by physical changes in the uterine lining Menstruation: The discharge of blood and tissue from the uterus at the end of menstrual cycle Mittelschmerz: Pain near the lower abdomen site at the time of ovulation; German for ovulation pain Mons Veneris: soft mound at the front of the vulva (fatty tissue covering the pubic bone) Ovarian Cycle: Last phase of the reproductive cycle; if no implantation occurs, causes the breakdown of the endometrial lining and causes menstruation Ovulation: The rupture of an ovarian follicle with the release of an ovum Perineum: External region between the scrotum and the anus in a male or between the vulva and anus in a female Premenstrual Syndrome (PMS): Time leading up to menstruation; includes both physical and emotional symptoms: acne, bloating, fatigue, backaches, sore breasts, headaches, constipation, diarrhea, food cravings, depression, irritability, difficulty concentrating or handling stress Puberty: The period of development in which the reproductive organs become functional and the secondary sex characteristics are expressed Reproduction: Process by which an organism continues its species Sexually transmitted diseases (STDs): diseases or infections that have a significant probability of transmission between humans by means of sexual contact Urethra: Located below the clitoris, used for the passage of urine Uterine Cycle: First part of the reproductive cycle; the time when the endrometrial lining builds up and follicles develop Uterus: Major reproductive organ, receives fertilized eggs which become implanted in the lining, the lining (endometrium) provides nourishment to developing fetus; contains some of the strongest muscles in the female body and is able to stretch during fetus development Vagina: Muscular, hollow tube that extends from the vaginal opening to the cervix Vulva: External female genitals, includes labia majora, labia minora, mons pubis, clitoris, meatus, vaginal vestibule, vestibule bulbs and vestibular glands - Essentials of Anatomy and Physiology. Fourth Edition. Valerie C. Scanlon and Tina Sanders. - Human Anatomy. Sixth Edition. Van De Graaff. - Wikibook: Sexual Health - American Social Health Association;ashastd.org
Edible Schoolyard NYC uses school gardens and kitchen classrooms to teach students about food — where it comes from, how it grows, how it’s prepared, and how it affects their health and their environment. Lessons emphasize hands-on activities in garden and kitchen settings, but also include student readings and manipulatives that deepen academic inquiry in related fields, such as science, mathematics, social studies, and language arts. All of our lessons support at least one Common Core standard as required by the NYC Department of Education. Download Our Curriculum Edible Schoolyard NYC invites educators to download our seed-to-table curriculum for use in their own classrooms. Lessons are divided into several PDFs. Select which lessons suit your needs, or download them all! Garden classes combine the fun, hands-on experience of gardening with a rigorous approach to related academic subjects. Our elementary garden curriculum consists of one lesson per month (taught either in two 50-minute periods or one 100-minute block), based on the seasonal needs of the garden. All lessons reinforce a particular academic discipline (math, ELA, science, social studies, etc.). For example: - Student scientists investigate the components of soil - Student historians study Native American agricultural techniques - Student poets compose verse inspired by the garden’s sensory appeal - Student mathematicians calculate and measure the spacing and depth of their plants Our middle school curriculum is organized into units combining garden work and in-depth academic exploration of a single topic, such as food justice, food marketing, and the politics and history of school lunch. Kitchen classes focus on one seasonal recipe per month (taught as either a 50- or 100-minute class), with age-level adaptations written into each lesson. Cooking offers students an authentic — and delicious! — opportunity to apply literacy and math skills as they follow a recipe. Lessons also incorporate opportunities for study of the cultures behind the foods prepared, as well as the science that explains the transformation food undergoes as it is cooked.
Big touch screens, like those used on smart phones and portable media devices, are great … unless the sun is out. Then the glare can be a killer, rendering some devices next to useless. Scientists have developed a test for analyzing reflection-resistant coatings to make using touch screen devices easier. The research also includes defining a better smudge-resistant coating to deter ugly fingerprints and scratches from screens and surfaces. Consumer electronics companies value the appearance and functionality of their ubiquitous devices and, hence, have created them with smudge, scratch and reflective resistant coatings, reported Dr Steven R. Carlo and colleagues at the 238th National Meeting of the American Chemical Society. And while these coatings are effective, their structure and mechanisms are poorly understood, said Carlo, whose colleagues developed a test to determine the chemical composition and effectiveness of smudge and reflective resistant materials. They believe this will lead to a better understanding of the chemistry of these coatings, allowing improved formulations and performance. "Surfaces are particularly important in consumer products. This work investigates how products can be modified to reduce smudging and reflections. These modifications can offer improved resistance to fingerprints, anti-reflection properties or enhanced physical resistance," Carlo explains. The basis of anti-smudge coatings is a compound called perfluoro alkyl ether, a derivative of Teflon with added ether groups to enhance its repellent effects. Anti-reflective materials use alternating layers of material, including silica and aluminum, to bend and diffuse light to reduce glare. Since traditional chemical techniques could not be used on these super-thin coatings, Carlo and his team used depth profile X-ray photoelectron spectroscopy (XPS) - a tool for comparing the chemistry of these coatings to predict their performance. The data allowed them to compare chain length, degree of branching and the hydrocarbon and fluoroether content of various samples. The fluoroether content has a key effect in enhancing the desired effect. Anti-reflective coatings need alternating layers, which have differences in their refractive index (RI), a measure of how fast light travels through a material. XPS allowed the scientists to visualize the multi-layer structure and the chemical species present in each layer - the greater number of alternate layers in a coating, the greater the anti-reflection qualities. Also, more silica and aluminum layers provide better glare reduction.
The Maginot Line was conceived as a self-contained system, eventually consisting of two distinct geographic regions. The main part of the line protected Alsace-Lorraine along the Rhine frontier. The Thionville-Metz region was the most heavily fortified and included the huge Hackenberg fortress, with more than 6 miles of underground galleries separated into sectors by heavy antiblast doors, connecting 17 combat blocks. Less known even today was what some sources call the Little Maginot Line. This line protected the French Alpine provinces facing Italy, including important mountain passes, with about 25 miles of continuing fortification down to the Mediterranean at Menton. One of these forts, Rimplas, was the first of the entire system to be built, beginning in 1928. In each region, the Maginot Line was made up of advance posts, major forts, support facilities, and lines of communication—all built to a standard plan and widely dispersed to withstand modern artillery attack. Located 3 to 6 miles behind the frontier, major ( gros) and smaller ( petit) infantry or artillery forts ( ouvrages) were built to make effective use of terrain to control transportation routes. Artillery pieces—mortars and howitzers—were especially designed for Maginot Line use and were housed in huge casemates, some with retractable turrets. (The largest howitzers were 134 mm caliber weapons.) Each fort had its own diesel power supply and storage deep underground. The largest forts were served by up to a thousand men able to operate for a month at a time, moved from one part of a fort to another by underground electric trains ( métro). Forts were located in positions that gave troops the ability to fire on their neighbors to fend off surface enemy attacks (which did not happen at Eben Emael) without harming the occupants (casemate reinforced concrete was more than 10 feet thick and then further protected with many feet of earth). Command-and-control facilities were often buried 60 or more feet deep, relying on input from fortified observation cupolas, an extensive buried telephone network, and radio links. All entrances (usually one for provisions and another for men) were heavily fortified, featured retractable drawbridges (or lifting bridges), and were made airtight against gas attack. There were also emergency entrances for all forts. What did the Germans know of the Maginot Line before the war? Actually, they knew quite a bit, much of it learned from the captured Czech border forts that were closely modeled on Maginot examples. Aerial surveys just before the war, spies, and interviews with many who had helped to construct the forts (some of them Germans!) gave the German military a good sense of where the Maginot Line forts were and what they could offer in resistance. The Germans did begin work in 1937 on the Gustav gun, with the intention of using it to crack the Maginot Line. The Germans were also well aware of the fatal flaw in the Maginot Line's geographic conception. Persuaded that no sizable military force could penetrate the dense Ardennes Forest region of southern Belgium, the line of forts stopped at that point, and only light fortifications (dubbed the Maginot Extension) were built along the Belgian frontier to the English Channel. The French plan was to advance into Belgium and assist their allies at the Belgian border fortresses. The plan depended on having enough time to move the requisite armies. When the German attack finally came in May 1940, of course, blitzkrieg tactics did not provide that time. Guderian's panzers and infantry broke through the Ardennes and turned the flank of the Maginot Line while other forces drove toward the Channel, cutting off British forces. The French, who could barely advance, were rapidly overwhelmed by the German onslaught. German attacks never breached the structures of any of the gros ouvrages, though some of the smaller outlying facilities were taken in fierce fighting because the surface forces supporting them had been withdrawn. And despite the German use of huge siege mortars and cannon, no major fort fell. Indeed, the Germans took only a few petit ouvrages on the far western end, even though they expended considerable effort and usually greatly outnumbered the defenders. To the south, the Italians never broke through the Alpine defenses, although they did directly assault the gros ouvrage of Cap Martin overlooking the sea in a failed attempt to gain control of the coast road. In the end, the Maginot Line accomplished exactly what it was designed to do—protect Alsace-Lorraine and the French provinces facing Italy. It did not "fail," despite the fact that some of its forts had not yet been fully armed. The existence of the line, originally designed to give the army time to mobilize and then attack, had clearly lulled France into complacency in the face of a rearming Germany and Italy. The French army fell into a defensive stance and ignored mobile warfare, as the High Command was convinced the line could contain any enemy attack. Only after the Germans occupied two-thirds of the nation did Maginot Line forces surrender with the rest of France. Forces stationed at many of the forts (e.g., Hackenberg and Simershoff) fought again in 1944 as the Allies neared the German frontier, and some of the fortifications were heavily damaged as they had not been in 1940. After the war, the French reoccupied and partially rearmed the Maginot Line, maintaining some forts into the 1960s; then, they were finally abandoned for good. A few facilities, such as a part of Hochwald, are still used by the French army or air force, generally for storage or communications. A number of ouvrages have been opened as museums; others are used to grow mushrooms or store wine. The rounded cement outlines of Maginot casemates will stand out against the terrain for decades to come. Christopher H. Sterling Kaufmann, J. E., and H. W. Kaufmann. The Maginot Line: None Shall Pass. Westport, CT: Praeger, 1997.; Kaufmann, J. E., and J. M. Jurga. Fortress Europe: European Fortifications of World War II. Conshohocken, PA: Combined Publishing, 1999, pp. 11–58.; Kaufmann, Joseph E. "The Maginot Line—German Intelligence before the War." Fort 26 (1998): 199–231.; Kemp, Anthony. The Maginot Line: Myth & Reality. Briarcliff Manor, NY: Stein and Day, 1982.; Mallory, Keith, and Arvid Ottgar. The Architecture of War. New York: Pantheon, 1973, pp. 90–107.; Rolf, Rudi, and Peter Saal. Fortress Europe. Shrewsbury, UK: Airlife, 1986.; Rowe, Vivian. The Great Wall of France: The Triumph of the Maginot Line. London: G. P. Putnam, 1959.; Truttmann, Philippe. La Muraille de France, Ou La Ligne Maginot. Thionville, France: Gerard Klopp, 1996. Christopher H. Sterling
How to make a full wave rectifier using SCR ? For full-wave rectification two SCRs are connected across the centre taped secondary, as shown in figure-a. The gates of both SCRs are supplied from two gate control supply circuits. One SCR conducts during the positive half cycle and the other during the negative half cycle and thus unidirectional current flows in the load circuit. The main advantage of this circuit over ordinary full-wave rectifier circuit is that the output voltage can be controlled by adjusting the gate current. Now if the supply voltage v = VMAX sin θ and the firing angle is a, then average voltage output will be given by the expression Vav = VMAX / ∏ (1 + Cos α) That is, average voltage output of full-wave rectifier circuit is double of that of half-wave rectifier circuit, which is obvious. Iav = VMAX / ∏RL (1 + Cos α)
As the term itself suggests, this method allows the students to choose the aspects of the target language that they would like to learn. Such a method resonates with the counselling approach whereby the teachers act as a counsellor and the student acts as a client. It is a community-based method where the students as a group are quite interactive. It pays a lot of attention to the feelings of the students. There are no any pre-determined technique followed in this approach. The content is decided by the group who’s willing to learn the language together. They come together and indulge in meaningful conversations. This is how the real meanings of the words and sentences are understood. The teacher, according to this approach, is considered to be a know-er and the student is referred to a learner. The roles are well adhered to. The teacher takes up the responsibility of understanding the concerns of the students and helping them in a detached yet considerate manner. Because this is a community-based learning, there might be some factors that are likely to hinder the process a bit. In case of a multi-lingual community, groups think, act and write in very different ways according to their own values, norms and culture. There might be some levels of awkwardness between the native and the nonnative groups. The native groups might feel threatened for not knowing the foreign language. Factors like lack of awareness of the nonnative cultures might also come into play affecting the success of this method adversely. Such a method might experience face issues like lack of social involvement. However, if such issues can be effectively solved, this method can allow a smooth process of learning languages. This is because the students have the liberty to choose the content.
Asperger’s Syndrome is an Autism spectrum condition. Autism is a life-long neurological developmental condition that impacts individuals in several key areas What is Aspergers? Asperger’s Syndrome is an Autism spectrum condition. Autism is a life-long neurological developmental condition that impacts individuals in several key areas: - Social communication - Social interaction - Social imagination - Sensory and information processing Asperger’s is not a mental health condition, but it is not uncommon for people with Autism to experience emotional health difficulties, especially anxiety. Around 1 in 100 people have Autism or Asperger’s Syndrome. Individuals are now more likely to be diagnosed in childhood, but there is an unknown number of undiagnosed adults living with the condition and it is still difficult for adults to access appropriate diagnostic services. Historically the diagnostic process was male-biased. This resulted in low numbers of girls and women receiving diagnosis due to differences in their presentation, and also because girls tend to be better at mimicking social skills and disguising their difficulties. People with Asperger’s Syndrome often have average or above average IQ. Their difficulties with social skills may appear to be ‘at odds’ with their general intelligence levels. They may have what are sometimes called ‘special interests’, whereby the individual has an intense interest in and may be extremely knowledgeable about one or more subjects. People with Asperger’s often make loyal and valued employees due to their high accuracy levels, attention to detail, and organisational skills; but without appropriate support and understanding may struggle with the social and sensory aspects of the work environment. Some common challenges - Difficulty reading and interpreting non-verbal communication (e.g. facial expressions, gestures, emotions and body language) can result in lack of confidence, confusion around what may or may not be going on, and difficulties in understanding what other people expect or want - Difficulty dealing with social interactions and group situations can mean that people with Asperger’s Syndrome become isolated and unable to access or join in with activities and events - Difficulty understanding the subtleties of social interaction and ‘putting yourself in someone else’s shoes’ can be interpreted as a lack of empathy, but it is hard for people with Asperger’s to respond appropriately or within the normal timescale as they need time to process all the information and work out what might be required of them - Sensory sensitivities (including sound, lighting, touch, taste and smell) – a simple visit to a shop can be an overwhelming experience - Eye contact can be extremely uncomfortable, even painful. Many people with Asperger’s find it easier to listen and concentrate if they do not make eye contact. - People with Asperger’s can be very literal in what they say and how they understand things, so may not appreciate metaphor or sarcasm - Rigid, ‘black and white’ thinking style, which makes it difficult to cope with sudden changes to plans or routine - A tendency to talk at length about their special interest and not be able to recognise the signs that others may be bored or not have time to listen - Lack of flexibility around their understanding of time (i.e. if an appointment is scheduled for a specific time, they may become anxious if things are delayed even though they understand intellectually that this may happen) - Some individuals have highly developed language skills, but may not always fully understand the meaning of some of the vocabulary they use. Common coping mechanisms - Ear defenders to help soften sounds (which can be very uncomfortable or painful), and reduce stress - Specialist tinted spectacles to help ease the discomfort caused by artificial lighting - Use of fidget toys as a means of easing stress and anxiety - Weighted blankets or cushions – deep pressure tends to be calming (light touch tends to be stimulating and stressful) - Movements such as ‘hand flapping’ or rocking are a means of easing stress - Choosing quieter times to do shopping or visit public places - Taking ‘time out’ when experiencing sensory overload Top tips for the community interacting with someone with Asperger’s. - A person with Asperger’s Syndrome may not always pick up on non-verbal cues, so you may need to explain what is going on to enable them to understand the full picture. - Give clear instructions, and allow the person time to process information and to respond. Written instructions can be helpful as the person can look at these later when they feel less overwhelmed by a situation. - Remember that if you tell someone with Asperger’s that something is going to happen at a specific time or place, they will tend to expect this to happen. Try to avoid making promises you may not be able to keep. - One-to-one interactions are often easier than group situations. - Do not force eye contact as this may make the person extremely uncomfortable and possibly impact on their ability to listen and concentrate. - If possible try to limit sensory and environmental challenges by switching off lighting, adjusting the volume of music, etc., or perhaps taking the person to a quieter area. - An individual may not realise if they are talking too much or focusing on a subject that is not of interest to the other person, so you may need to gently guide the conversation back to ‘topic’ or remind them about ‘turn taking’. - Some people on the spectrum carry Autism/Asperger’s Awareness Cardswhich provide brief information about the condition and contact details should further help and support be required.
Facts about Botulism - Centers for Disease Control and Prevention Frequently Asked Questions - What is botulism? - What are the symptoms of botulism? - How soon after exposure do symptoms occur? - What is the treatment for botulism? - How is botulism diagnosed? - Can botulism be prevented? - Can botulism be used as a bioterrorism threat? Botulism is a serious illness caused by a nerve toxin (poison), produced by the bacterium Clostridium botulinum. These bacteria are found naturally in soil throughout the world, and are harmless when oxygen is present. When they are in an environment that contains no oxygen, they produce the toxin. Botulism usually occurs in three forms: Foodborne botulism is caused by eating foods that are contaminated with botulinum toxin. A common cause of this type of illness is improperly processed home-canned foods with low-acid content, such as green beans and corn, and lightly preserved foods such as salted or smoked fish. Intestinal botulism is rare, but is more often seen in children younger than a year old, rather than older children or adults. It previously was referred to as infant botulism. This type occurs when an infant consumes something that is contaminated with the C. botulinum spores, which then grow in the baby’s intestines and produce toxins. In most cases, the source of spores is not identified, and these may be airborne from soil or dust. Intestinal botulism has been associated with consumption of honey that has not been certified to be free of C. botulinum spores. Wound (skin) botulism is a rare disease occurring when C. botulinum spores contaminate a wound, grow within the wound and produce toxin that is absorbed into the bloodstream. This type of botulism has been associated with gross trauma, crush injuries and injection with black tar heroin from Mexico. A person can be exposed by breathing in the toxin if it is intentionally released into the air. This does not occur naturally. Foodborne and intestinal botulism produce symptoms that affect the nervous system. The classic symptoms include double or blurred vision, drooping eyelids, slurred speech, difficulty swallowing, and dry mouth. Muscle weakness descends through the body: it begins at the shoulders and moves down to the upper arms, lower arms, thighs, calves and feet. If untreated, these symptoms may progress to paralysis. Infants with botulism appear lethargic, feed poorly, are constipated and have a weak cry and poor muscle tone. Generally, symptoms begin 12-36 hours after eating contaminated food, but may occur as early as a few hours and as late as 10 days. The incubation period for intestinal (infant) botulism is unknown, though estimated at 3 to 30 days from the time of exposure. For wound botulism, the incubation period is 4 to 14 days from the time of the injury until the onset of symptoms. The symptoms of botulism make hospitalization necessary. If diagnosed early, foodborne and wound botulism can be treated with an antitoxin that is maintained by the Centers for Disease Control. The antitoxin reduces the progression of paralysis and may reduce the severity and duration of symptoms. Most patients eventually recover after weeks to months of supportive care. An investigational human derived botulinal immune globulin is available from the California Department of Health for the treatment of intestinal (infant) botulism. Antibiotics are of little use to treat the symptoms caused by the toxin, and should be avoided in intestinal botulism because lysis of the bacteria could increase the amount of toxin available for absorption. If left untreated, a patient may need to be on a ventilator for weeks and would require intensive medical and nursing care. The annual fatality rate for cases in the United States is 5-10 percent. Because botulism occurs rarely, and the symptoms are similar to other neurological diseases, diagnosis is difficult and the disease may be misdiagnosed. The laboratory test used to confirm a diagnosis of botulism is sensitive and specific but can take several days to complete Yes. Follow proper home canning techniques (required time, pressure and temperature) to destroy spores. Do not eat food from damaged cans (food cans with slits, holes, dents or bulges). Do not feed honey or honey-water to infants younger than 12 months of age. Botulinum toxin has been a concern as a potential biological warfare agent since World War II. The extreme toxicity of the toxin, the ease of production, transport and delivery make this an agent of bioterrorism concern. Individuals intentionally exposed to the toxin, breathing it in or ingesting it in contaminated food or water could develop botulism. It is unknown what the effects of inhaling the toxin are, but they may be similar to the foodborne type of the disease. For more information about botulism, call the Vermont Department of Health, Epidemiology Field Unit, at 1-800-640-4374 (in VT only), or 1-802-863-7240.
So I was sitting around, thinking of nothing in general, when the idea struck me that to me gravity seems instantaneous. Realizing this is rather unlikely (many people at one time would have regarded light as instantaneous as well), I googled speed of gravity. Well, it seems the only experiments conducted as yet have been flawed, and this puzzles me. You see, it occurs to me that if the speed of gravity is different from light, then we have in our hands an entirely new way of communicating, among other things. If this is significantly faster than light, then the possibilities in my mind are endless (and I shall not list them all here.. lol). So I propose two experiments, one to determine the speed of gravity here on earth, and one to determine its speed in a vacuum, if different (but somehow, I doubt it is... common sense just tells me otherwise): 1. We place an electromagnet on one side of the earth. On the opposite side we place a detector. We pulse the magnet. Given the diameter of earth (about 7900 miles) and the speed of light (about 186,000 miles/second in a vacuum), there should be a .0425 second delay if the speed of gravity is the same as that of light (in a vacuum). This is a very detectable delay by modern electronics. In fact, a shorter distance should easily suffice; say, Caltech to MIT or something. This would decrease the necessary strength of the magnet considerably. 2. Same thing, but from a satellite to something placed on the moon, or another satellite, etc, provided they are in a high-enough orbit to be effectively in a vacuum, and far enough apart for the delay to be detectable. Now. Surely I am not the only one with this thought, so why hasn't this happened. Can we not detect changes that minute in the gravitational field? Can we not create a magnet powerful enough? It wouldn't need to be pulsed long enough to start drawing in cars, buildings, lab techs with too high a blood-iron count, etc., so there shouldn't be a "public danger" argument... Why can't this be done??
The chimpanzee is the closest animal relative to humans. Credit: Anne Fischer, Max Plank-Institute for Evolutionary Anthropology A new study of genes in humans and chimpanzees pins down with greater accuracy when the two species split from one. The evolutionary divergence occurred between 5 million and 7 million years ago, an estimate that improves on the previous range of 3 million to 13 million years in the past. Modern chimps are the closest animal relative to humans. Knowing when the two split has implication both for understanding how quickly evolution works and for imagining the likelihood of intelligent beings elsewhere in the universe, researchers said today. "There is considerable interest in knowing when we diverged from our closest relative among animal species," said Sudhir Kumar of Arizona State University. "This divergence time also has considerable importance because it is used to establish how fast genes mutate in humans and to date the historical spread of our species around the globe." Kumar’s team used a recently developed method in genetic sequencing to make the most comprehensive comparison to date of genes from humans, chimps, macaque monkeys and rats. They examined the number of mutations in the DNA sequence of each species to estimate its rate of evolutionary change. The results were released today in the online version of the Proceedings of the National Academy of Sciences. The work does not exclude a broader time frame but makes it very unlikely. "We can conclude that humans and chimpanzees probably last shared a common ancestor between five and seven million years ago," said research team member Blair Hedges, an astrobiologist at Penn State. “Knowing the timescale of human evolution, and how we changed through time in relation to our environment, could provide valuable clues for understanding—in a more general sense—the evolution of intelligent life."
Studying a dead distant planet could help humans to know more about the way in which Earth will finally die and perish, a new study report published in the journal Science says. Recently, researchers while monitoring a distant star in deep space stumbled upon an orbiting fragment of a dead, shattered planet, and experts believe that this could be actually a preview of Earth's inevitable fate in the future. The study report claimed that the discovery of this planetary fragment orbiting around a white dwarf could shed light into the twilight years of planetary systems. Experts believe that the newly found planetary chunk could be actually a piece of the planet's shattered core. Scientists also speculate that the planet might have perished brutally during the star's death throes. Researchers also revealed it is quite remarkable that the dead planet's fragments survived the extremely intense gravity of the white dwarf star. "The white dwarf's gravity is so strong — about 100,000 times that of the Earth — that a typical asteroid will be ripped apart by gravitational forces if it passes too close," said Christopher Manser, lead author of the study and a physicist at the University of Warwick in Coventry, England, said in a statement. The study report suggested that the planetary chunk might be orbiting around the star every two hours, and no larger than 250 miles in diameter to avoid being ripped apart by the white dwarf's gravitational force. Scientists also revealed that both the dead star and the planetary chunk are located in our Milky Way, at a distance of 410 light years away from the Earth. Experts believe that Earth could also face a similar fate when the sun swells into a red giant. As the sun swells, it will consume Mercury, Venus, and Earth, and will later shrink turning into a white dwarf.
The did America have to gainWhat Panama Canal from the Panama Canal? 1. Describe the process by which America acquired the land rights to the Panama Canal zone.2. What did America have to gain from the Panama Canal? Consider the economic, political, scientific, and cultural aspects of this question as they apply both to the U.S. and to the world. "Panama Canal Profits", New York Times, November 16,1920 The Canal Record reports that last year the operating expenses of the Panama Canal were $6,548,272, and the receipts were $8,935,871, "leaving a profit of $2,387,599. [$26,031,514 -2010]" Since the opening of the canal the cost of operation has been $36,657,766, and the revenues $34,657,766. It is agreeable to know that the canals last year was its best, and it may confidently be expected that the commerce of peace through the Isthmus route will surpass that of war. The canals best years are before it, and it was not built for the sake of profit. It would justify its existence even if it did no more than double the efficiency of our fleet.Time Lapse Voyage“Panama Canal Profits” New York Times, 1920 1970sThe Panama Canal is used extensively for the transport of material and troops during theVietnam War.On average, over 15,000 ships a year use the canal.1974Tolls are raised for the first time from 90 cents to $1.08 per cargo ton.The following year, the passenger ship Queen Elizabeth II will pay a record toll of$42,077.88.1999The U.S. hands over sovereignty of the Panama Canal to Panama.2007Under the 2007 construction plan, the Panama Canal Authority is planning to double thecapacity of the canal.The project is slated to create up to 45,000 new jobs, increasing employment on the canalby 10-15%. When construction is completed in 2014, the Panama Canal will be capable ofhandling up to 600 million tons of cargo per year and seven additional lockages each day.By 2025, the Panama Canal is projected to earn more than $6 billion annually.Canal Expansion Review the readings. Respond to the prompts. Work in groups.Write a 5-8 sentence history of the Panama Canal 1. The Panama Revolution. Describe the process by which America acquired the land rights to the Panama Canal zone. Why was the American public "confused and very divided" upon learning of the revolution in Panama? List arguments for and against. 2. The path to Americas future. What did America have to gain from the Panama Canal? Consider the economic, political, scientific, and cultural aspects of this question as they apply both to the U.S. and to the world. In what ways did President Theodore Roosevelt see the canal as "the obvious path to Americas future"? What is your assessment of Roosevelts interest in the canal? Was he inspired? Arrogant? Visionary? Imperialist? Explain.Key Terms:Theodore Roosevelt Charles de LessupsJohn Hay Hay-Bunau-Varilla TreatyColombia Monroe Doctrine
If you suspect your child has autism spectrum disorder (ASD), your journey to understanding your child’s health challenges may include an autism spectrum test. Undertaking an autism spectrum test can be an emotional time for both parents and children. One way to combat this is to understand what testing will involve and why diagnosis is important. We’ve put together this helpful fact sheet to help demystify ASD testing and help you prepare for an upcoming autism spectrum test. Why is ASD testing important? There are a number of benefits to having your child undertake an autism spectrum test. Once your child has been diagnosed with ASD, they are able to get the help that they need. Having the right paperwork – including a formal medical ASD diagnosis – is imperative to accessing the support services available. Many parents also find that ASD testing helps alleviate emotional stress associated with not understanding their child’s needs. Who can diagnose autism? The medical experts that are legally able to diagnose autism vary from state to state across Australia. As diagnosis typically happens during childhood, diagnosis usually involves a multi-disciplinary team of doctors, including paediatricians, childhood psychologists or psychiatrists, speech pathologists and occupational therapists. What does an autism spectrum test involve? As ASD means something different for everyone, there is no set criteria for a medical test or diagnosis. Rather, medical experts come together to carry out many different assessments, which contribute to a holistic view of how severe your child’s ASD may be. On the assessment day, medical experts will conduct different assessments to evaluate whether an individual has ASD. There are four main areas that are assessed. These are: 1. Behaviour and Family History The first assessment will usually involve a childhood psychologist or paediatrician interviewing the parents and family members of the child undergoing ASD testing. This is to paint a clear picture of the child’s behavioural history, as well as to see if there’s a history of ASD in the family. 2. Communication skills As communication is one of the key areas impacted by autism, the next phase of assessment will involve a speech pathologist or therapist engaging the child in different communication tasks. With tests involving verbal and non-verbal tests and pragmatic language skills, this phase of assessment aims to gauge how well the child can communicate and how they use language. 3. Cognitive abilities Depending on the age of the child, they may be asked to complete different cognitive tests. For children who are of school age, they may be asked to complete written literary and numeracy tests, as well as IQ tests, to gauge their cognitive levels against standardised benchmarks for their age. 4. Medical assessment Finally, medical assessments may be carried out to evaluate a child’s physical health and uncover any phsical ailments that may impact their results. This usually includes hearing and vision tests, blood tests and genetic testing, as well as an electroencephalogram (EEG) to test brain activity. What happens after ASD testing? Once your autism spectrum test has finished, your doctors will advise you on next steps. Some children may have a clear indication of ASD, while others may require further testing or evaluation. If your child’s autism spectrum test comes back with a positive diagnosis, then the next steps will be to seek out an early intervention service. The Australian government provides a lot of support through the NDIS to help fund early intervention programs for children with autism, which can have a huge impact on ensuring your child gets the best possible start to life. Lizard Centres are located all around Australia and run specialist early intervention programs for children with autism. We have extensive knowledge on the NDIS and can help you access your NDIS funding. Reach out to our friendly team today to talk about how we can get your child the help they need.
Caitlin Stier, video intern Boa constrictors don't waste time strangling their victims. By sensing when their prey's pulse stops, they know when to release their grip. In this video, Scott Boback and his team at Dickinson College serve a boa a warmed-up dead rat to see how it attempts to suffocate it. Although the rat has no pulse, it shows how the boa wraps itself around its prey, suggesting which surfaces contain sensors below the skin. During the manoeuvre, the boa also adjusts its position to save energy. When clenching a dead rat, a boa would usually stop squeezing after about 10 minutes. But in tests with a simulated pulse, the snake would keep gripping it for about 20 minutes. According to the researchers, it's the longest example of constriction for both live and dead mammals. To find out more, read our full news story: Boas sense when prey's heart goes still.
I’ve previously talked about emotionally engaging your reader, or giving your audience an emotional response to improve your screenplays, but how do you define emotion? That’s a bit like trying to define love and create it in a test tube. But here goes anyway. Emotions can be broadly defined as a mental and physiological changes in response to an external stimuli evoking feelings, behaviours and thoughts. Hopefully the stimulus is your screenplay. Punch up every scene with emotion. Take your audience through a rollercoaster ride. Make them feel many emotions in a scene, one after the other. Make them laugh. Make ’em cry, and not by peeling onions. The only thing that should be flat is your stomach. The five basic human emotions are happiness, sadness, love, anger and fear. Two are positive and two are negative. Anger is an interesting response, because it relates to “fight or flight” situations, where we must act to protect ourselves and sits somewhere in the middle It is associated with the release of adrenalin. Our hearts beat faster, we sweat, our concentration improves, we become alert and lose some our ability to feel pain. Some psychologists believe all are emotions lie along a spectrum polarized by fear on one end and happiness on the other. Everything else is a subcategory of these two key emotions. Psychologists have characterized emotional response in terms of basic human needs. If these needs are unbalanced or unmet, then a negative response occurs. If they are met.. well we’ve all been in love and floated on clouds. If we experience them in abundance (manic behaviour), then we have psychological problems. Consider Maslow’s Hierarchy of Human Needs. ABRAHAM MASLOW’S THEORY OF HUMAN MOTIVATION – HIERARCHY OF HUMAN NEEDS These are listed from the basic to more evolved. Typically they are structured as a pyramid. - Physiological – breathing, food, water, sex, sleep, homeostatis, excretion. These are unconscious actions designed to keep us alive. - Safety – security, body, employment, resources, morality, family, health, property, shelter. These are conscicous actions designed to protect us. - Love/ Belonging – friendship, family, sexual intimacy. These are sociological actions designed to boost relationships. We are social animals. - Esteem – self-esteem, confidence, achievement, respect of others, respect by others. These are outgrowths of ego designed to allow us to function in a community. - Self- Actualization – morality, creativity, spontaneity, problem solving, lack of prejudice, acceptance of facts. These are egocentric behaviors allowing us to function as individuals. Karl Iglesias has defined emotions in stories as being voyeuristic (allowing audience to experience a character) and sympathize with them), vicarious (allowing audience to empathize with a character and identify with them, and visceral (primal emotions such as anticipation, relief, dread, suspense). A good story is built on a character wanting something and something or someone opposes their efforts. In its rudimentary form, this is called conflict which creates drama in a script. In terms of stories, Karl Iglesias has reduced scripts to requiring four emotional elements. Audience love stories to satisfy the following needs: - to obtain new information - to bond/ socialize - to understand and resolve conflicts - to get completion/ closure - to be entertained So there you have it. Add some resonance to your scripts and give them some impact. For in depth Film & TV script analysis visit Script Firm.
for Postsecondary Students This Web topic explores how self-determination—the combined skills of self-awareness, self-advocacy, self-efficacy, decision-making, independent performance, self-evaluation, and adjustment—can contribute to an individual’s ability to establish and achieve his or her goals during and after higher education experiences. Postsecondary education and training is considered a gateway to high-skilled jobs of the 21st century. Although more students with disabilities are entering higher education than in the past, the majority leave before completing their program or degree. One reason for this is that many youth with disabilities lack the self-determination skills—such as the ability to articulate their strengths and advocate for their needs—necessary for success in postsecondary education and ultimately the workplace. Without necessary accommodations, students with disabilities may become discouraged with their lack of success and may discontinue their postsecondary education. A possible explanation for students’ limited development of self-determination is that many educators are unaware of how to help them develop such skills. In addition, students may have limited opportunities to make choices and act independently. As a result, many students with disabilities exit high school with little experience in self-advocacy, which is an important self-determination skill for negotiating new responsibilities in postsecondary education and the workplace. Other pages on this topic: ^ Top of Page ^
Smart Pebbles: To test their algorithm, researchers designed tiny cubes with built-in processors and magnets. Imagine that you have a big box of sand in which you bury a tiny model of a footstool. A few seconds later, you reach into the box and pull out a full-size footstool: the sand has organized itself into a large-scale replica of the model. Researchers at MIT’s Computer Science and Artificial Intelligence Laboratory have developed an algorithm that could make such “smart sand” possible. The grains of sand would be tiny computational devices that can pass messages to each other and selectively attach to their neighbors; in their research, the MIT team modeled the grains with cubes measuring about 10 millimeters to an edge. The cubes had rudimentary microprocessors inside and switchable magnetic connectors on four of their sides. Algorithmically, the main challenge in developing smart sand is that such tiny grains would have very few computational resources. “How do you develop efficient algorithms that do not waste any information at the level of communication and at the level of storage?” asks Daniela Rus, a professor of computer science and engineering and a coauthor with her student Kyle Gilpin on a paper presented at the IEEE International Conference on Robotics and Automation in May. Rus and Gilpin’s answer is to convey shape information with a simple physical model. To see how the algorithm works, picture each grain of sand as a square in a two-dimensional grid. Now imagine that some of the squares—say, forming the shape of a footstool—are missing. That’s where the physical model is embedded. The grains pass messages to each other to determine which have missing neighbors. Grains with missing neighbors are in one of two places: the perimeter of the sand heap or the perimeter of the embedded shape. Once the grains surrounding the embedded shape identify themselves, they pass messages to other grains a fixed distance away, which in turn identify themselves as defining the perimeter of the duplicate. If the duplicate is supposed to be 10 times the size of the original, each grain surrounding the embedded shape will map to 10 grains of the duplicate’s perimeter. The grains not used to form the duplicate shape detach from their neighbors and simply fall away as the assembled object is lifted from the heap. The cubes that Gilpin and Rus used in experiments enact this simplified, two-dimensional version of the system. But computer simulations demonstrate that the algorithm would work with a three-dimensional block of cubes, too, by treating each layer of the block as its own two-dimensional grid. The same algorithm can be varied to produce multiple similarly sized copies of a sample shape or to produce a single large copy of a large object. “Say the tire rod in your car has sheared,” Gilpin says. “You could duct-tape it back together, put it into your system, and get a new one.”
1) Rhododendron luteum - Also called Yellow Azalea or Honeysuckle Azalea. - Despite the sweet perfume, the nectar is toxic. Records of people poisoned by eating the honey date back to 4th century B.C. - Cultivated both as an ornamental and as root stock. 2) Laburnocytisus adamii - Also known as Adam’s laburnum or broom laburnum. - Considered a horticultural curiosity, some branches produce yellow flowers while other branches produce coppery-pink flowers. - Located along Arboretum Drive south just south of the Sassafras. 3) Paeonia Lutea var. Ludlowii - A rare Chinese form of tree peony. - Large saucer-shaped blooms appear in late spring in a beautiful clear yellow color. - Avoid pruning except to remove large branches. - Located along Arboretum Drive across from the Sequoias. 4) Petteria ramemtacea - Fragrant yellow flowers in early summer and tri-foliate leaves make this unusual plant resemble a shrubby golden chain tree. - Native to Yugoslavia and Albania. - This specimen is located along the east side of Arboretum Drive behind the Dove Tree. 5) Sophora microphylla - Known as the Kowhai tree in its native New Zealand. - The blooms of the Kowhai are regarded as New Zealand’s national flower. - All parts of the Kowhai, but particularly the seeds, are poisonous to humans. - Located along Arboretum Drive
Slavery existed in the United States even before the United States existed as a nation, but slavery had not always divided northern and southern states from each other. How the United States transformed from a slaveholding to a non-slaveholding nation stands as one of the most dramatic episodes in American history. The transformation was long and painstaking in many ways but abrupt and revolutionary in others. Massachusetts played important, though complicated, roles in the processes that ended slavery in the United States. This website features more than fifty primary sources from the collections of the Massachusetts Historical Society and the Library of Congress that reveal how slavery, and debates about slavery, contributed to the formation of the United States. Using letters, diaries, broadsides, artifacts, songs, legal notebooks, and photographs representing a variety of viewpoints, this site highlights the complex nature of ideas about slavery and freedom that circulated in the eighteenth and nineteenth centuries. The sources are arranged into five thematic areas:
What is a biobank? A biobank is a large and organised collection of biological materials that can b… Clinical trials are an important part of medicines development, and the development of other types of treatment such as medical devices and vaccines. The development of a treatment requires several stages: clinical trials refer to those stages that involve testing in humans. Clinical trials are generally carried out in three phases (and are known as phase 1, 2 and 3, or I, II and III). Alternative names include ‘proof of mechanism’ or ‘exploratory’ studies (phase 1), ‘proof of concept’ studies (phase 2) and ‘confirmatory’ or ‘development for launch’ studies (phase 3). Clinical trials for rare diseases have previously been seen as more difficult than trials for common conditions because of the small numbers of people who are affected and are able to take part in the trials. New study designs are now making clinical trials for rare diseases more feasible. Phase 1 clinical trials are designed to test whether a treatment is safe in humans. They also look at whether the treatment behaves in humans in the same way it behaved in earlier experiments involving animals. These studies provide information on the way that the medicine works: the ‘mechanism of action’. Around 20 to 100 volunteers are included in phase 1 clinical trials, and they are usually healthy, male volunteers. The trials are generally carried out in special units. Clinical trials are guided and regulated by a set of international standards known as Good Clinical Practice (GCP) to protect the safety of the subjects in the study. Phase 1 clinical trials start with a very low and single dose of the treatment; once it has been shown that there are no safety concerns with this first dose, the study can continue with a slightly higher dose. This type of study is known as a Single Ascending Dose (SAD) study. This is usually followed by a Multiple Ascending Dose (MAD) study which involves giving multiple doses per volunteer over time. Other studies within a phase 1 clinical trial may also be carried out; for example, studies investigating the effect of food or other medicines on the function of a new medicine. Once a phase 1 clinical trial in healthy volunteers has shown that it is safe to proceed, the next step is to start clinical trials in patients with the disease that is being treated. Because phase 2 clinical trials are carried out in patients, they are usually run in several different hospitals. The same guidelines and regulations apply as for phase 1 clinical trials. In phase 2 (and phase 3) clinical trials, volunteers are usually split into two groups. One group has the new treatment and one group receives the current best treatment, or a dummy treatment which has no effect on the body (called a ‘placebo’). These trials are normally ‘double-blind’ and ‘randomised’. ‘Double-blind’ means that neither the doctor nor the volunteer knows who is receiving the new treatment or current best treatment or placebo. ‘Randomised’ means that the allocation of each volunteer into one of the groups is done by chance. This is usually done with a computer that generates a random code. It cannot be influenced by the doctor or anyone else. When one of the groups receives a placebo, the trial is known as ‘placebo-controlled’. This allows the trial to identify any effects that are caused by the new treatment. For example, if a volunteer in a study complains of a headache it is important to know if that is related to the new treatment. If the same number of volunteers receiving placebo complain of headaches, this shows that the headache cannot be due only to the new treatment. Phase 2 clinical trials are generally too small to provide enough evidence about a new treatment’s safety and how well it works (efficacy) for it to be authorised for use. But the information they provide is important in deciding whether to proceed to phase 3 clinical trials, which are the most complicated and expensive phase of development. Phase 3 clinical trials are the largest, most complicated, and most expensive part of the development of a treatment. They aim to confirm the safety of a new treatment, and how well it works, in a large patient population. The decision to go on to phase 3 clinical trials is only made if supported by all the information gathered from earlier studies. The design of such studies normally requires discussion with external experts, regulatory authorities, patient groups and others. This ensures that the right questions are being asked by the clinical trial, and the right information is being collected. The trial design will also include what dose(s) to test; which patients can be recruited (inclusion criteria); which patients cannot be included (exclusion criteria); how many patients are required. The number of patients in a phase 3 clinical trial is important so that the results can be properly interpreted and will meet the requirements of the regulatory authorities who will ultimately decide whether to authorise the treatment for use. At this stage, the trial may involve thousands of patients. However, this depends on what the treatment is intended for (the ‘indication’). Phase 3 clinical trials are also often run across several countries. When designing clinical trials in small populations, a balance needs to be made between what is necessary and what is possible to help researchers understand the effects of new treatments. The dilemma is to recruit a sufficient number of volunteer patients when only a very limited overall number of patients with the disease exist. Clinical trials for rare diseases require: The use of ‘adaptive design’ for clinical trials is becoming common for small populations. For instance, adaptive design allows researchers to look into the results during the course of the trial (rather than waiting to the end) and to stop a specific treatment being given to one group of volunteers if no positive effect is seen there. Another option with adaptive design is to combine phases 2 and 3 of the clinical trial to reduce the overall number of patients required. The content on this page is provided for free, non-commercial use under a Creative Commons CC BY-NC-SA 4.0 copyright licence. This content is adapted from the "The A to Z of how medicines are developed", copyright EUPATI.
Jet Engine Compressor Blade A used compressor blade from a 1969 Rolls Royce Avon axial flow jet engine. Great learning aid for airfoil geometry. Coated aluminum alloy with OEM stamps Length: 3 ⅝" The Rolls-Royce Avon was the first axial flow jet engine designed and produced by Rolls-Royce. Introduced in 1950, the engine went on to become one of their most successful post-World War II engine designs. It was used in a wide variety of aircraft, both military and civilian, as well as versions for stationary and maritime power. An axial compressor is a compressor that can continuously pressurize gases. It is a rotating, airfoil-based compressor in which the gas or working fluid principally flows parallel to the axis of rotation, or axially. This differs from other rotating compressors such as centrifugal compressors, axi-centrifugal compressors and mixed-flow compressors where the fluid flow will include a "radial component" through the compressor. The energy level of the fluid increases as it flows through the compressor due to the action of the rotor blades which exert a torque on the fluid. The stationary blades slow the fluid, converting the circumferential component of flow into pressure. Compressors are typically driven by an electric motor or a steam or a gas turbine. An airfoil is the cross-sectional shape of a wing, blade (of a propeller, rotor, or turbine), or sail. An airfoil-shaped body moved through a fluid produces an aerodynamic force. The component of this force perpendicular to the direction of motion is called lift. The component parallel to the direction of motion is called drag. Subsonic flight airfoils have a characteristic shape with a rounded leading edge, followed by a sharp trailing edge, often with a symmetric curvature of upper and lower surfaces.
We often have an outbreak of skin rashes or allergy without any prior symptoms. According to the allergists, this may happen due to the interaction of our body with pollens, which travels inside the room through human breathing. And this increases rapidly during the fall or winter season as most of the plants pollinate during this time of the year and it finds a way to your bedroom and clothes even without your knowledge. Understanding the type I reactions: The allergy outbreaks, which happen immediately after engulfing or coming in contact with specific foreign particles or what the researchers commonly call allergens either through nose or mouth in the form of sneezing, coughing, or hives and skin allergy are known as “type I reactions” or “immediate hypersensitivity reactions.” Specifically, people allergic to pollen, animal dander, mold spores, dust mites are prone to the type I reaction which is quiet instant. To know the symptoms of these hyper allergic reactions, one has to be alert about the stages of development of allergy in the body. Stage I: sensitization phase Generally, the typical allergens like pollen enter the mucous membrane of the nose or mouth and pass on to the respiratory tract. It is the task of the Immunoglobulin E (Ig E) to react to any foreign particle entering the body causing sensitivity which is deployed as allergy or rashes. Stage II: preparative phase IgE cells are present in tissues of the respiratory tract, gastrointestinal tract, and skin. These cells bound to the tissues are called mast cells. These mast cells are equipped with IgE molecules that specifically recognize a particular antigen. Once any foreign particle enters the body, these antibodies recognize the antigens that have entered our system. Stage III: the battle phase The reaction between antigen and antibody starts once the foreign particle enters the body and the immune cell bind to the antigen and there is when an outbreak of rashes occur. During this phase, histamine is released into the body. These chemicals produce inflammation, swelling, itching, redness, and other symptoms of common allergies. Stage IV: late phase Many people responses to delayed reaction due to the immune system and allergen reaction which may extend up to 24 hours. Ways to prevent allergy: Allergy can be prevented in a best possible by identifying the substance that causes outbreak by the aid of effective allergy testing methods and avoiding that particle. Whenever you experience a specific type of reaction every time, you come across a substance or eat a food item, consult a health physician to detect the actual cause of the problem.
Even as much as 30 per cent of natural gas used in the UK could be replaced by hydrogen – this has recently been revealed by a study conducted at the Swansea University. This would reduce CO2 emission by 18 per cent. Natural gas is a fuel widely used in Great Britain. It is commonly used for generating electric power and, by households, for heating and cooking. Until recently this fuel accounted for 80 per cent of energy consumed in Great Britain in winter months, when heating costs need to be taken into account. One of the ways to limit emissions from natural gas is to add hydrogen to it. As a result, the side product of combustion is only water vapor, however, the physical features of hydrogen are slightly different from those of methane – lower calorific value and much lower density. It also has some problematic features, like the tendency to leak through various materials and escape from pipes and containers. According to research by Dr Charles Dunhill and Dr Daniel Jones from Energy Safety Research Institute, even 30 per cent of hydrogen may be added to methane without any major complications. Adding more than that would result in making the gas useless in households. The scientists say that blending hydrogen with natural gas is the first step towards building hydrogen-only installations in the future, without having to use fossil fuels at all. Now, an Australian city of Adelaide is conducting advanced tests of a technology which in its heating system uses natural gas with a 10 per cent hydrogen blend. How to produce hydrogen Unlike mining of fossil fuels, obtaining hydrogen usually does not require any gross interference with natural environment. Today’s most popular method of obtaining hydrogen is steam reforming – producing hydrogen from methane and steam at a temperature of 700-1,100 degrees Celsius. This is the most cost-effective way of an industrial-scale production of this gas – the amount of hydrogen obtained per one unit of energy is much bigger than in electrolysis. On the other hand, though energy efficiency of electrolyzers leaves a lot to be desired, the prospects of using electrolysis are very interesting. First of all, renewable energy surplus may be stored in hydrogen. For example, power-to-gas technology provides for electrolytic production of hydrogen, which is later used in the gas network. Hydrogen may also be stored and used whenever needed. Although the efficiency of this process today is still low, it allows using energy from renewable sources when surpluses of that energy are available. However, today this technology is still costly.
Pacific populations of sweet-tasting Dungeness crabs are on the decline, and researchers from the University of Toronto say they’ve found a potential culprit: acidic ocean water related to climate change. The acidic water affects how molecules bind to the crabs’ smell-detecting antennae, which they use to scavenge for food on the sea floor. For the Dungeness, as with most crabs, its sense of smell is critical to its survival, as it has poor vision and relies on short antennae for finding food, mating and avoiding predators. The antennae “flick” through the water, allowing scent molecules to collide with nerve cells on the appendages, which transmit to the crab’s brain. “Losing their sense of smell seems to be climate related, so this might partially explain some of the decline in their numbers,” says Cosima Porteus, an assistant professor at the University of Toronto-Scarborough, in a press release. The Dungeness Crab Fishery Because of its sweet, firm flesh, the Dungeness crab stands as one of the most popular types of seafood in the world, with more than 50 million pounds harvested each year. The study values the industry, in 2019, at about $250 million. Dungeness crabs get their name from a bay found near Dungeness Spit in Washington State, although the commercial fishery stretches across the American and Canadian Pacific Coast. Like other fisheries, the Dungeness harvest must deal with an increasing amount of carbon dioxide in the atmosphere, which ocean water absorbs, turning it more acidic. While other studies have looked at the effects of climate change on marine wildlife, “This is the first study to look at the physiological effects of ocean acidification on the sense of smell in crabs,” Porteus says. How Dungeness Lose Their Sense of Smell For the study, the researchers exposed crabs to acidified water and found that they flicked less, and not only that, their antennae collected 50 percent fewer scents. As a result, they became much less sensitive to crucial environmental cues. “Crabs increase their flicking rate when they detect an odour they are interested in,” says Porteus, “but in crabs that were exposed to ocean acidification, the odor had to be 10 times more concentrated before we saw an increase in flicking.” Acidic water, the study found, had caused the scent-detecting neurons to malfunction, making them less responsive. The cells also appeared to have shrunk by as much as 25 percent. Worn-Out Crabs Don't Lay Eggs “These are active cells and if they aren’t detecting odors as much, they might be shrinking to conserve energy,” she says. “It’s like a muscle that will shrink if you don’t use it.” Lack of food means lack of energy, Porteus says, and lack of energy may mean a decline in egg-laying and overall populations, a cycle that may also be affecting snow and Alaskan king crabs.
Social determinants of health (SDOH) are the conditions in the environments where people are born, live, learn, work, play, worship, and age that affect a wide range of health, functioning, and quality-of-life outcomes and risks. SDOH can be grouped into 5 domains: Healthy People 2030, U.S. Department of Health and Human Services, Office of Disease Prevention and Health Promotion. https://health.gov/healthypeople/objectives-and-data/social-determinants-health People without steady employment and who live in poverty are more likely to suffer from health issues and have limitations to the work they can perform. Many people are working but are still living below the poverty line. Many are not offered or cannot afford health insurance. Economic stability includes employment programs, career counseling, and high-quality childcare opportunities. But there is still more that needs to be done. Subsidized payments for food, housing, health care, and education can reduce poverty and improve health and well-being. Policies at the local, state, and national levels need to be continuously evaluated and reformed Access to quality education can be restricted for a large number of students. Children from low socioeconomic households and children with disabilities are more likely to struggle with schoolwork. They are also less likely to graduate from high school or continue with post-secondary education. Many public schools in low economic areas do not perform at the levels of schools in more affluent communities. The burden of tuition for better education or college is not even an option for many families. Even the stress of living in poverty can affect children’s brain development. Programs to help children and adolescents succeed in school and help families pay for further education have long-term health benefits Many families do not have access to health insurance. People with no health insurance are less likely to have a primary care provider and receive recommended health care services, such as cancer screenings. Many cannot afford the tests and medications they need. Location is also key to health care. Families in remote areas may not have transportation to doctor’s offices or hospitals. Many emergency services in rural areas have extremely stretched their resources. They can transport a patient to a hospital, but if another call comes in, that patient needs to wait thirty minutes, an hour, sometimes more, for the ambulance to return and get them. This extended time can be critical to the health of the patient. Strategies to implement pathways, both face to face and remotely, to health care professionals can help more people get the care they need and save lives. The communities and neighborhoods where families reside have a huge impact on their health and welfare. Neighborhoods with high crime rates, health risks, and safety risks are just one component. Lower-income areas may have housing with inadequate heating or no access to potable water. Work environments can also cause health concerns, such as exposure to asbestos or lead paint. Implementing policies to help reduce these risks and improve communities can promote health. Adding streetlights can help lower crime rates, and bike and walking paths can encourage exercise. These contribute to a better quality of life for all residents. Relationships and interactions with family, friends, co-workers, and community members have a major impact on health and well-being. Obstacles and barriers that are out of a person’s control, such as unsafe neighborhoods, discrimination, or trouble affording the things they need, create negative impacts on health and safety. Positive relationships within these areas can help reduce these negative impacts. However, some individuals do not have the support they need in the home, work, or community. Interventions to help people get the social and community support they need are critical for improving health and well-being.
Kepler's Discovery of Planetary Asymmetry Breaking away from the unnatural bond of circular symmetry was no easy task for Kepler. For he was shaken at being compelled to abandon a circular orbit and to question his faith in the Divine Geometer. Having cleared the stable of astronomy of circles and spirals, he was left, he said, with 'only a single cartful of dung' a stretched out circle something like an oval1 The elliptic orbit of a planet is a short-term description of a long-term trajectory of the planet that approximates to an ellipse rotating about the Sun as the exaggerated animation below shows. More precisely, the Sun and planets are together rotating in a state of balance about a pivot which is just a point in 'empty' spacetime. We shall see in due course that the ultimate pivot of physical balance is a point not even in empty spacetime, let alone in matter, but somewhere else as spacetime and matter are themselves constituents of the ultimate architecture of the physical world. 1. Carl Sagan, Cosmos, Macdonald & Co(Publishers)Ltd, Maxwell House, London EC2A 2EN, 1981, p 62. Symmetry was first defined by Hermann Weyl, and this definition effectively means 'invariance under operation'. Accordingly, a symmetry property of a system is one that remains invariant under an operation (sometimes called a transformation) performed on the system. Figure 1, below, is a schematic illustration of symmetry operation. As a special case, symmetry property can be the system itself; the simplest example of this case is the plane circle, as it remains unchanged if rotated arbitrarily about the perpendicular axis through its centre. Note that 'symmetry property' and 'operation' belong together, which means that each type of operation defines its own kind of symmetry. For example, everyday use of objects is a type of operation that leaves most of these objects approximately invariant, or constantly recognisable; hence, in everyday life symmetry objects of an approximate kind surround us. Above definition of symmetry is too general to serve as an analytical tool in physics. However, in conjunction with Group Theory symmetry operations form a group with considerable analytical power. A fundamental feature of this group is the reversibility, or the invertibility, of operation that, strangely enough, gives the concept of 'operation' an antisymmetric character. Thus the symmetry group of operations itself is contingent on the state of inseparability between symmetry and antisymmetry. However, they are not present on an equal footing as a given symmetry feature is the result of a pair of arbitrary antisymmetry operations. That inequality is both the strength and the fundamental weakness of the Symmetry Group. An example of its strength is its ability to endow a particle of matter with an arbitrary linear velocity of an invariant magnitude. In other words, Symmetry Group enables us to theorise a particle of matter linearly moving anyhow in spacetime. However, this ability comes at a price; the price of decoupling of boost and rotation, in simpler language, decoupling of linear and rotary motions, in still simpler language, decoupling of spacetime and matter. Symmetry or antisymmetry, just by itself unconditionally, is not in the field of human experience. What system of objects in the material world possesses just symmetry or antisymmetry? According to Pauli Exclusion Principle, not even two coupled electrons are interchangeable and hence not symmetric under the operation of interchange, against what appears as obvious to common sense. Also a particle and its anti-particle are not antisymmetric as they have the same mass. If symmetry and antisymmetry exist together on an equal footing, then among various symmetry operations, there has to be at least one operation that applies to both. Such an operation, indeed, does exist, and we encountered it as ‘interchange’ in the previous paragraph. If two entities, on interchange, remain invariant then they are in a state of symmetry with respect to the interchange operation, but if they become somehow inverted then they are in a state of antisymmetry. These two states are idealistic extremes and as a rule two entities are neither completely symmetric nor antisymmetric. Let t and v denote two isotypic fundamental physical entities. Then their symmetry and antisymmetry components under the simplest form of the interchange-operation of t and v are a (t + v) and ± b (t - v) respectively, where a and b are scaling factors. The simplest fundamental forms of t and v are the kinetic and the potential energies of a mechanical system and their symmetry and antisymmetry components are the Hamiltonian and the Lagrangian, respectively. We know that these are the true infrastructural components of a mechanical system and not t and v, but this latter is our only means of accessing the former. Let us take this opportunity to discuss briefly symmetry and antisymmetry in relation to how they naturally occur in the physical world. Consider the four fundamental physical interactions, Gravitation, Electromagnetism, Strong and Weak. The first two are long-range interactions rooted in symmetric and antisymmetric tensor fields, respectively, of the remaining two short-range nuclear interactions, Weak and Electromagnetism merge at high energies of the order of 100 GeV, and Strong, owing to its insensitivity to charge, may exhibit a similar behaviour with Gravitation. Therefore, the field aspect of the physical world presents excellent evidence that Nature weaves her field-fabric of the physical world with just the two interlocking patterns of symmetry and antisymmetry. First, consider pure static balance shown schematically below. The two weights W1 and W2, at point of balance, are both equal to, say, W. Then one-half of their sum is W and one-half of their difference is zero. Therefore the symmetry measure, based on the operation of interchange of the two weights, is W and the antisymmetry measure, based on the same operation, is zero. Now consider the simple pendulum, which is a case of dynamic balance between the kinetic and potential energies T and V of the pendulum bob. These energies are the counterparts of W1 and W2 that we considered above in relation to pure static balance. Potential energy V depends on a zero-reference level that we can set arbitrarily. Let us choose this level to be the highest point reached by the pendulum bob. This choice is unique for the following reason. Kinetic energy of the pendulum does not depend on the potential reference. It is completely independent of it. The choice we made for the potential reference equates potential energy to that kinetic energy and hence in that sense the choice is unique. With this unique choice, the simple pendulum becomes a model of pure dynamic balance. We now have, T = K and V = - K where K varies from zero to a maximum Kmwhich occurs when the pendulum bob is at its lowest point. The symmetry measure of T and V, which is (T + V)/2, is zero and the antisymmetry measure, which is ± (T - V)/2, works out to ± K; therefore the energies are in a state of pure antisymmetry. For small oscillations, Km is proportional to the product of the length of the string and the square of the amplitude of oscillation. However, according to quantum mechanics, energy of an oscillatory motion does not depend on the amplitudes, but depends only on the frequencies involved. The simple pendulum also simulates this quantum mechanical condition if we allow the pendulum length to vary freely, but infinitesimally slowly to keep this variation decoupled from the pendulum swing. The precise mathematical analysis of this dual motion is available on pages 114 and 115 of Max Born's book, Atomic Physics (Blackie & Son Limited, 1972). Proper Physical Balance Proper physical balance exhibits features of both pure static and pure dynamic balance that we discussed, above. In each of these two cases, the magnitudes of the two entities in balance are the same. Let us call it the Equality Condition. In the pure dynamic balance two orthogonal motions are present, one oscillatory and the other linear (such a dual motion, albeit trivial, is present in the pure static balance also). Let us refer to it as the Orthogonality condition. For the pure static balance, the antisymmetry measure of the two entities in balance is zero, and for the pure dynamic balance, the symmetry measure is zero. Let us label each of these as the Null condition. Equality Orthogonality and Nullity ( more accurately Null Singularity) that we referred to above are all necessary conditions of proper physical balance. They may also be sufficient. In the physical world, from a practical and observational point of view, the primary pair of physical entities in balance is the pair of vectors that represent the linear and the angular motions of a fundamental particle of matter. If these two vectors are a and b, then according to the first of the above three conditions, their magnitudes are equal. According to the second condition, their scalar product ab is zero. Finally, according to the third, the magnitudes of the vectors (a + b) and ± (a - b) are also zero. However, the triple criteria of balance are satisfied not only by the pair, linear and angular, but also by each of the remaining two pairs of the triple pair-formation Symmetry - Antisymmetry Spacetime - Matter of the physical world that we encountered in the About page. In static balance, fulcrum is in a passive role. In dynamic balance, we found that there is activity at the pivotal point due to varying pendulum length. Therefore, there is room to think that the fulcrum in dynamic balance is in a reasonably active role. In the real physical world, this involvement of the fulcrum is at an extreme and is quite complex and deep. The pivot end of this fulcrum is what we perceive presently as the Microwave Background radiation and the rest of the fulcrum is perhaps Dark Energy. There is an elegant real-life example that illustrates this complexity and depth quite effectively. Consider the final of a grand slam tennis match such as that epic battle between the tennis supremos Nadal and Federer at Wimbledon in 2008. In such situations players, without doubt, satisfy the Equality criterion. They are free to act independently and yet they remain connected via the tennis ball; therefore, the act of playing tennis is one of relative freedom, as in Orthogonality. At a grand slam final, the outcome of the match is contingent on mental agility rather than on physical strength. In other words, the players occupy a plane of reality on which it is the mind and not the body that is at play; hence, they also satisfy the criterion of physical Nullity. Even with the triple criteria satisfied, the match has no meaning without the complex infrastructure consisting of a well-constructed tennis court, an umpire, line judges, ball boys and girls and hawk eye and other similar high-tech devices. In the language of balance, all these collectively represent the fulcrum, which, on occasion, is even able to tip the balance in favour of one player or the other. Because of life's singularity.......... The map is not the territory... ( by Ven Sochu) One of the most famous parables told by the Buddha is the Parable of the Raft. In this he likened his teachings to a raft for crossing a fast-flowing river. The parable narrates how a man is trapped on one side of a river. On this side, there is great danger and uncertainty and on the far side of the river is safety. However there is no bridge spanning the river nor is there a ferry to cross over. What to do? The man gathers together logs, leaves, and creepers and by his wit fashions a raft from these materials. By lying on the raft and using his hands and feet as paddles he manages to cross the river from the dangerous side to the side of safety. The Buddha then asks the listeners a question. What would you think if the man, having crossed over the river thought to himself – That raft has served me well I will carry it on my back over the land now? The monks replied that it would not be a very sensible idea to cling to the raft in such a way. The Buddha went on – What if he lay the raft down gratefully thinking that this raft has served him well but is no longer of use and can thus be laid down upon the shore? The monks replied that this would be the proper attitude. The Buddha concluded by saying – So it is with my teachings which are like a raft and are for crossing over with not for seizing hold of. This parable marks the attitude taken to the teachings given by the Buddha, firstly that their prime objective is to be of practical use and secondly to introduce the teaching of the Two Truths. The ultimate Truth or Reality cannot be described by words and concepts and must be seen for oneself. However the path that leads to that insight can be described and forms a map to show how to get there. This truth is relative because it only describes the way to this Truth it is not the Truth itself nor is it the path itself. The Buddhist practitioner must walk this path; it is not enough just to read about it or even to believe that it works! Thus we must always bear in mind that the teachings, even the story of the Life of the Buddha are only descriptions, symbols pointing to something beyond the words and neither must they be taken as scientific fact or even historical truths. is why it is futile to become bogged down in ontological or epistemological arguments over these teachings. The value of them is realised when they are used in the way they were designed to be used as a practical tool leading toward insight into the human condition.
The 17-page Kids' Wings unit for the Deborah Wiles's novel, Each Little Bird That Sings, will enable your students to build basic skills while collaborating in the reading of this touching story, told by 12 year old girl, filled with compassion and endearing relationships. The surprising conclusion adds a touch of sadness. The unit guides student study in exciting reading activities for an excellent easy novel set in a family funeral parlor in fictious Snapfinger, Mississippi. Activities in the unit include: - a logic puzzle to introduce characters, - anticipation guide, - predict/confirm chapter questions, - crossword puzzle, - multiple choice chapter check-ups, - Using Resources to Check Facts, - Editing and Revising a Letter, - Be the Illustrator, - Mapping the Story, - Describing the Character of the Story's Character, - Math Scaling the Map, - Writing Prompts, and - answer pages.
An unmanned aerial vehicle (UAV), commonly known as a drone, as an unmanned aircraft system (UAS), or by several other names, is an aircraft without a human pilot aboard. The flight of UAVs may operate with various degrees of autonomy: either under remote control by a human operator, or fully or intermittently autonomously, by onboard computers. Compared to manned aircraft, UAVs are often preferred for missions that are too „dull, dirty or dangerous“ for humans. They originated mostly in military applications, although their use is expanding in commercial, scientific, recreational, agricultural, and other applications, such as policing and surveillance, aerial photography, agriculture and drone racing. Civilian drones now vastly outnumber military drones, with estimates of over a million sold by 2015. The term drone, more widely used by the public, was coined in reference to the resemblance of dumb-looking navigation and loud-and-regular motor sounds of old military unmanned aircraft to the male bee. The term has encountered strong opposition from aviation professionals and government regulators. „Worker bees can leave. Even drones can fly away. The Queen is their slave.“ — Chuck Palahniuk The term unmanned aircraft system was adopted by the United States Department of Defense and the United States Federal Aviation Administration in 2005 according to their Unmanned Aircraft System Roadmap 2005–2030. The International Civil Aviation Organization and the British Civil Aviation Authority adopted this term, also used in the European Union’s Single-European-Sky Air-Traffic-Management Research roadmap for 2020. This term emphasizes the importance of elements other than the aircraft. It includes elements such as ground control stations, data links and other support equipment. A similar term is an unmanned-aircraft vehicle system remotely piloted aerial vehicle, remotely piloted aircraft system. Many similar terms are in use. A UAV is defined as a „powered, aerial vehicle that does not carry a human operator, uses aerodynamic forces to provide vehicle lift, can fly autonomously or be piloted remotely, can be expendable or recoverable, and can carry a lethal or nonlethal payload“. Therefore, missiles are not considered UAVs because the vehicle itself is a weapon that is not reused, though it is also unmanned and in some cases remotely guided. The relation of UAVs to remote controlled model aircraft is unclear. UAVs may or may not include model aircraft. Some jurisdictions base their definition on size or weight, however, the US Federal Aviation Administration defines any unmanned flying craft as a UAV regardless of size. A radio-controlled aircraft becomes a drone with the addition of an autopilot artificial intelligence (AI), and ceases to be a drone when the AI is removed. The earliest attempt at a powered UAV was A. M. Low’s „Aerial Target“ in 1916. Nikola Tesla described a fleet of unmanned aerial combat vehicles in 1915. Advances followed during and after World War I, including the Hewitt-Sperry Automatic Airplane. The first scaled remote piloted vehicle was developed by film star and model-airplane enthusiast Reginald Denny in 1935. More emerged during World War II – used both to train antiaircraft gunners and to fly attack missions. Nazi Germany produced and used various UAV aircraft during the war. Jet engines entered service after World War II in vehicles such as the Australian GAF Jindivik, and Teledyne Ryan Firebee I of 1951, while companies like Beechcraft offered their Model 1001 for the U.S. Navy in 1955. Nevertheless, they were little more than remote-controlled airplanes until the Vietnam War. In 1959, the U.S. Air Force, concerned about losing pilots over hostile territory, began planning for the use of unmanned aircraft.Planning intensified after the Soviet Union shot down a U-2 in 1960. Within days, a highly classified UAV program started under the code name of „Red Wagon“. The August 1964 clash in the Tonkin Gulf between naval units of the U.S. and North Vietnamese Navy initiated America’s highly classified UAVs
Lesson Notes for Teachers is appropriately explicated in this article to guide you on the things required of you as a teacher. Before You Write a Note of Lesson Lesson Notes for Teachers Writing lesson notes is an integral part of teaching. In short, it is impossible to go through a college of education without having to study a course on lesson note writing. Read Also: How to Write an Article: 10 Helpful Steps A teacher who does not have a note of the lesson is not worthy of teaching as there is nothing he or she will have to offer to the learners in his or her classroom. However, it takes a lot of time and energy to write a good lesson note that will be used to teach children beginning from the gathering of materials, and understanding of the needs of the learners to the content development, a teacher has to be very deliberate without which the main purpose of writing the note will be defeated. In this article, we will be showing you what you need to consider before or when writing your note of lesson. Before You Write a Note of Lesson Here are the Things to Consider Before You Write a Note about the Lesson: 1. Consider why you are writing the note of the lesson This should carefully answer the question, ‘What will these children learn after I have taught them the content of my note?’ with that question in mind, you will be able to put your pen to work and script out the necessary information that is needed in your note and you mustn’t stop planning and writing your note until these objectives are met. Read Also: How to Write a Business Plan Your objectives need not be conclusive, for instance, if you are teaching preschoolers who do not know how to write, your objective of introducing a topic to them may simply be to help them hold the pencil which is pointing to help them learn how to write. 2. Plan the time adequately Your lesson note is more or less a guide to everything you will do in the class. It should include the timing of the lesson. When you do not time everything you will be doing in the class, you might end up overshooting a period and eating up the time allocated for another subject or class. 3. View your students as you plan What makes a lesson note good or bad is if it was accepted by all the students in the class. Take note of this when planning your class; there are three kinds of learners: Auditory, Kinesthetic, and Visual. Some people are one of these while others are merely a combination of all three styles. When planning your lesson, make sure that all three styles of learning are covered. You may need to include a provision for playing audio or videos in the course of your teaching just to ensure that all the students learn adequately. Read Also: How to Write a Biography about a Famous Person 4. Use different teaching methods in your lesson notes Don’t be rigid, make room for different styles within a lesson. The ultimate goal is for the learners to grasp what has been taught if one style is not yielding the desired result, do well to opt-in for another style. 5. Give room for unplanned events Even if you are teaching the top graders, always do well to leave room for uncertainties. Don’t plan up all your time, allocate 10-20 minutes to unplanned events which may stem in the form of questions, accidents, or contributions. Remember that it is like learners to be inquisitive, your lesson should give them that space. Whether you are a novice or a pro-teacher, the aim of your lesson at all times must be to meet the educational need of that student in your class, and at the end of your class, students should leave better than they came in. If this is not achieved, learning has not taken place.
What You Need to Know Amblyopia, also known as lazy eye, is an eye condition caused by underdeveloped pathways between the eye and the brain. Amblyopia usually only affects one eye, but can occasionally affect both eyes. Most of the time, the eye has a normal structural anatomy but a defective pathway; the brain ignores the images from the lazy eyes. If amblyopia is detected early in life, it can be corrected. However, if amblyopia is treated too late, the brain will become accustomed to ignoring visual inputs from the eyes leading to decreased vision in the lazy eye. WHAT ARE THE SYMPTOMS? If your child or infant has amblyopia, you may notice that he/she has crossed eyes (also known as strabismus) or cries without explanation when one eye is covered. Strabismus is a prevalent cause of amblyopia so if you notice any signs, schedule an appointment with an eye doctor for further evaluation. Other symptoms of amblyopia, most common in older children and adults, include double vision, poor depth perception, squinting or shutting one eye when reading, or tilting the head to one side. How Is Amblyopia Treated? Amblyopia can be treated by using eye patches or by instilling topical atropine into the eyes. Eye patches are usually worn on the dominant eye. Wearing an eye patch on the dominant eye ensures that the lazy eye is forced to function so a pathway from the eye to the brain can be formed. Initially, your child may complain of difficulty in seeing, but as time goes by the lazy eye will adjust, and vision will improve. It is important that your child wear his/her patch because not treating amblyopia young can lead to lifelong vision problems. Topical atropine is usually prescribed in the form of eye drops. Atropine is the treatment modality of choice in mild cases of amblyopia. Atropine dilated the eye therefore blurring the vision in the good eye forcing the lazy eye to compensate for sight. Glasses and surgeries can be used to correct underlying eye conditions that led to amblyopia. Glasses are usually prescribed as a treatment option for amblyopia when the underlying cause is a refractive error (a condition where one eye sees images more clearly than the other eye). These glasses help the lazy eye view images better, and the brain is forced to receive the correct visual input from the lazy eye. Eventually, the brain gets familiarized with using both eyes, and normal vision develops. Correcting these eye defects will subsequently lead to correction of lazy eyes. Surgery is indicated for people who have strabismus or cataract as the underlying cause of amblyopia. However, even after surgery an eye patch may be necessary. Call to make an appointment today if you are concerned about amblyopia.
Researchers examining deposits from ancient hydrothermal vents in northeastern Canada have found evidence of microbial activity, possibly some of the earliest life on Earth. Hydrothermal vents deep beneath the oceans have long been thought to be where life originated, leading Matthew Dodd and colleagues to search where they did. The microbes were likely iron-metabolizing bacteria, and the structures they left are between 3.77 and 4.28 billion years old, making them even older than the microbes found last year to have lived near the surface of the ocean 3.70 billion years ago. We spoke with Dodd to learn more about the findings. ResearchGate: What was Earth like 3.7 billion years ago? Matthew Dodd: Earth would have been a completely different place than today. It certainly would not have been as green as it is now—mostly barren, rocky surfaces pitted by impact craters. Little to no oxygen would have meant no ozone layer and no blue coloring to the sky. Extensive volcanism would have been common, and very small amounts of continents would have been present. RG: Why did you search for signs of life where you did? Dodd: We chose the Nuvvuagittuq belt because of its age—3.77 to 4.28 billion years—and because of the rocks there: pillow basalts with chemical similarities to mid-ocean ridge basalt and iron formations, long suspected to be the products of hydrothermal venting and precipitation. Given the long-standing theory that the origin of life happened in hydrothermal vent environments, we knew that these rocks were perfect choices to look for Earth’s oldest life-forms. RG: How certain is it that these signs are an indication of life and not something else? Dodd: The significant observations we made include tubular hematite structures and filaments attached to terminal knobs, all of which are also found in younger hydrothermal vent deposits. The first line of evidence of life are the intricate morphologies, such as twisted stalks and tubes preserved by millions of nanoscopic grains of iron. Their presence made these very convincing candidates for microfossils. Yet, due to the history of controversy surrounding early life studies, we sought additional lines of evidence. We found these in the form of isotopically light carbon in graphite, associated with carbonate and apatite in and around the microfossils. Isotopically light carbon can be produced when organisms preferentially select the light isotopes to process carbon, suggesting these organic remains are biological. The association of organic carbon (graphite) and apatite occurs in younger rocks, where phosphorus-bearing, biological organic matter decays, releasing phosphorus into the sediments and forming the phosphate mineral apatite. Furthermore, we found these same minerals inside granules which occur in the rocks hosting the microfossils. Granules can form from the decay of organic matter and, in younger rocks, can be found enclosing fossils of trilobites. It is these multiple, independent observations, which all occur together in the same rocks with the microfossils, that provide overwhelming evidence for the biological origin of these tubes and filaments. RG: What kind of life would this have been? Dodd: Based on the morphology of similar microfossils and organisms alive today in hydrothermal vent environments, these organisms were likely iron-metabolizing bacteria, which oxidized iron coming out of hydrothermal vents to provide energy for themselves to grow and fix carbon. RG: How does this finding fit into the known timeline of life on Earth? Dodd: This discovery demonstrates life had already become quite complex in shape 4.28 to 3.77 billion years ago, pushing the origin of life on Earth to near the beginning of the formation of Earth. In conjunction with another study, reporting stromatolites from 3.70 billion years ago, this finding shows life had at that time already evolved to live in both shallow marine environments—using sunlight to grow and form stromatolites—and to use iron minerals to grow around hydrothermal vents. This finding also fits with other studies that trace back phylogenetic trees of life and suggest the origin of life took place in iron-rich hydrothermal systems four billion years ago. RG: Could this research have implications in searching for life on other worlds? Dodd: Certainly. Because we’re finding evidence for life on Earth at a time when not just Earth but also Mars had oceans on its surface, we should expect to find evidence for life on Mars 3.77 to 4.28 billion years ago. If not, then Earth must have been a special exception. This also shows that hydrothermal vent environments were also one of the first places, if not the first, occupied by life on Earth. They should therefore be the priority targets to search for life elsewhere in the universe. A version of this article originally appeared on ResearchGate. Featured image: Haematite tubes from hydrothermal vent deposits that represent the oldest microfossils and evidence for life on Earth. Credit: M. Dodd
X-ray vision reveals how polymer solar cells wear out Synchrotron study suggests how the manufacturing process can be improved 2016-10-24 – News from the Physics Department Unlike conventional solar cells, which are made of silicon, organic solar cells produce electricity in an active blended layer between two carbon-based materials. When one of these is a polymer, the resulting cell is often referred to as a polymer solar cell. These are particularly promising because they can be manufactured simply and cheaply. They can be used to make extremely lightweight, flexible and even semi-transparent solar cells using printing techniques on flexible polymer materials, opening up completely new fields of application. In general, however, organic solar cells are less efficient than silicon-based ones, and sometimes they have also a reduced lifetime. Important inner values The internal structure of the active layer is crucial in organic solar cells. When manufacturing them, the two materials that form the active layer have to separate out of a common solution, much like droplets of oil forming in water.“ It is important that the polymer domains formed in the process are a few tens of nanometres apart,” points out Christoph Schaffer, a PhD student in the Prof. Müller-Buschbaum, Chair for Functional Materials at TU Munich. “Only then positive and negative charge carriers can be efficiently produced in the active layer and separated from each other. If the structure is too coarse or too fine, this no longer happens, and the efficiency of the solar cell will decrease.” Modern polymer solar cells often consist of so-called low-bandgap polymers, which absorb particularly large amounts of light. In many cases, these require the use of a solvent additive during the manufacturing process in order to achieve high efficiencies. However, this additive is controversial because it might further decrease the lifetime of the solar cells. X-ray view into the solar cell The scientists used DESY’s x-ray source PETRA III to study the degradation of such low-bandgap polymer solar cells with solvent additives in more detail. To this end, a solar cell of this type was exposed to simulated sunlight in a chamber, while its key parameters were continuously monitored. Parallely, the scientists shone a narrowly collimated x-ray beam from PETRA III at the solar cell at different times, providing a picture of the internal structure of the active layer on a nanometre scale every few minutes. “These measurements can be used to relate the structure to the performance of the solar cell and track it over time,” explains co-author Prof. Stephan Roth, who is in charge of DESY’s P03 beamline, where the experiments were conducted.“ The data reveals that domains that are on the scale of a few tens of nanometres shrink substantially during operation and that their geometric boundaries with other components disappear,” says Schaffer. At the same time, the measurements suggest that the amount of residual solvent additive decreases. The scientists attribute the measured drop in the efficiency of the solar cell to the observed decrease. “Since there is evidence to suggest that the residual amount of solvent additive decreases, we have to assume that this process can limit the lifetime of the solar cells,” explains Müller-Buschbaum. “Therefore it is essential to come up with strategies for stabilising the structure. This could be achieved through chemical bonding between the polymer chains, or using customised encapsulating substances.” Size is critical In an earlier study, the Munich researchers observed the degradation of a different type of polymer solar cell. In that case, the efficiency was found to drop as a result of the active centres gradually growing in size during their operation. This suggested that it is in fact better to manufacture such solar cells with a suboptimal structure, i.e. one that is too fine, so that it can then grow to the optimum size during the first hours of operation. The current study picks up the story where the previous one left off. “Our first study showed us that the efficiency dropped when the structure became coarser,” says Schaffer. “Exactly the opposite happens in the present study. This behaviour is precisely what we expected, because the composition of the active layer is different.” “The materials in the first study tend to demix to a high degree,” explains Schaffer. “Here, the opposite is true, and we need the solvent additive in order to achieve the demixing of the materials that is needed to obtain high efficiencies. When the solvent additive disappears during operation, the structure becomes finer and therefore moves away from its optimum.” Both these studies offer important approaches to optimising the manufacturing of organic solar cells, as co-author Roth points out: “The way these two studies fit together provides a wonderful example of how important synchrotron radiation has become, especially in applied research such as in the field of renewable energies.” - Prof. Dr. Peter Müller-Buschbaum - Technische Universität MünchenJames-Franck-Str. 185748 GarchingTel.: +49 89 289-12451E-Mail: [email protected]
Electrical installations almost always require protection against short-circuits wherever there is an electrical discontinuity. This most often corresponds to points where there is a change in conductor cross-section. The short-circuit current must be calculated at each level in the installation in view of determining the characteristics of the equipment required to withstand or break the fault current. The flow chart in Figure 1 indicates the procedure for determining the various short circuit currents and the resulting parameters for the different protection devices of a low-voltage installation. In order to correctly select and adjust the protection devices, the graphs in Figures 2, 3 and 4 are used. Two values of the short-circuit current must be evaluated: The maximum short-circuit current, used to determine - The breaking capacity of the circuit breakers - The making capacity of the circuit breakers - The electrodynamic withstand capacity of the wiring system and switchgear The maximum short-circuit current corresponds to a short-circuit in the immediate vicinity of the downstream terminals of the protection device. It must be calculated accurately and used with a safety margin. The minimum short-circuit current, essential when selecting the time-current curve for circuit breakers and fuses, in particular when: - Cables are long and/or the source impedance is relatively high (generators, UPSs) - Protection of life depends on circuit breaker or fuse operation, essentially the case for TN and IT electrical systems Note that the minimum short-circuit current corresponds to a short-circuit at the end of the protected line, generally phase-to-earth for LV and phase-to-phase for HV (neutral not distributed), under the least severe operating conditions (fault at the end of a feeder and not just downstream from a protection device, one transformer in service when two can be connected, etc.). AUTHOR: Schneider Electric experts | Benoît de METZ-NOBLAT, Frédéric DUMAS, Christophe POULAIN |Title:||Calculation of short-circuit currents| |Download:||Right here | Video Courses | Membership | Download Updates|
by Gertrud U. Rey Errors during viral replication can give rise to shortened and/or rearranged genomic sequences known as “defective viral genomes” (DVGs). Because DVGs often lack critical elements needed for replication and formation of new viral particles, virions containing DVGs can only complete a replication cycle if they co-infect a cell together with respective full-length (i.e., wild type) viruses. To replicate their genomes, DVGs often hijack missing proteins from the wild type viruses, a phenomenon that can result in suppression of wild type virus replication. There is increasing evidence to suggest that this suppression can be exploited for the development of antiviral agents. Marco Vignuzzi at the Institut Pasteur has been exploring this idea by investigating the antiviral potential of DVGs produced during infection of cells with various viruses. In an effort to capture DVGs as they were formed in cell culture, Vignuzzi and colleagues infected mammalian and mosquito cells with Chikungunya virus, a mosquito-borne virus that causes symptoms similar to those caused by dengue virus. They then isolated newly emerging virions from the cells and used those particles to infect new cells – a cycle that was carried out 10 times in a technique known as serial passaging. Sequencing and quantification of viral genomes isolated from the last passage revealed that the number of DVGs increased by about 100,000 between the first and last passage. The most prevalent DVGs were sorted into four groups, with DVGs within each group having deletions of similar sizes and at similar genomic locations. Three of the groups included mostly DVGs derived from mammalian cells and the fourth group included mostly DVGs derived from mosquito cells. To determine whether DVGs are also generated in an infected arthropod, the authors infected Aedes aegypti mosquitoes with Chikungunya virus by allowing them to feed on virus-infected blood. Ten days after infection, the mosquitoes were dissected, total RNA was isolated, and DVGs were identified by sequencing the RNA using DVG-specific primers. This analysis revealed that the DVGs produced in mosquitoes had similar deletion patterns and profiles as those produced in cell culture, suggesting that DVGs are generated both in cell culture and mosquitoes. All subsequent studies were done using 20 mammalian- and mosquito-derived DVGs that occurred most frequently and persisted through all passages. To confirm that the DVGs were indeed defective and unable to replicate inside a cell in the absence of full-length virus, the authors introduced (i.e., “transfected”) RNA molecules encoding each DVG into mammalian cells and extracted total RNA from the cells at 8, 20, 28, and 44 hours post-transfection. DVG RNA was then quantified by PCR using primers specific for the respective DVGs. The authors observed that in contrast to wild type virus levels observed in control cells, which increased steadily over time, DVG levels decreased across all time points. This finding confirmed that in the absence of wild type virus DVG RNA was not replicated, but degraded over time. To see whether the 20 DVGs actually interfered with replication of wild type virus, the authors transfected mammalian cells with a 1:1 ratio of an RNA encoding a DVG and an RNA encoding a full-length fluorescently-tagged wild type Chikungunya virus, so they could monitor the presence of the wild type virus by fluorescence microscopy at various timepoints. Wild type Chikungunya viruses transfected together with most DVG-encoding RNAs continued fluorescing strongly at 48 hours post-transfection, suggesting that most DVGs did not inhibit or reduce the replication of wild type virus when transfected at a 1:1 ratio. However, when the DVG/full-length virus ratio was increased to 10:1, fluorescence of full-length Chikungunya viruses decreased by 10 – 1,000-fold in the presence of almost all DVGs, suggesting that a higher ratio of most DVG RNAs increased the likelihood of these genomes to confiscate needed replication elements from wild type viruses and thus interfere with their reproduction. Interestingly, the smallest DVG with the biggest deletions did not seem to interfere with wild type virus replication, probably because this genome was missing too many elements and could not be adequately compensated by the presence of full-length virus. Overall, these results suggested that both mammalian- and mosquito cell-derived DVGs can interfere with wild type virus replication in mammalian cells. Remarkably, when this experiment was repeated in mosquito cells, most of the mosquito cell-derived DVGs that could inhibit wild type virus replication in mammalian cells were unable to do so in mosquito cells. Although the exact reason for this effect is unclear, it is possible that the prevalence of arthropod-borne viruses in mosquitoes has led these viruses to evolve some resistance to the effects of DVGs during viral replication in mosquitoes. The authors also found that although most DVGs only inhibited Chikungunya virus strains that were closely related to the strain they were derived from, a small number of DVGs also inhibited more distantly related viruses like Sindbis virus, suggesting that DVGs may be capable of inhibiting a broad range of viruses. In a final set of experiments aimed to evaluate the ability of the DVGs to prevent viral spread within mosquito hosts, the authors injected mosquitoes with DVG-encoding RNAs, and two days later they infected them with a fluorescently-tagged wild type Chikungunya virus. A control group of mosquitoes was only infected with Chikungunya virus but did not receive any DVGs. Five days after infection, the mosquitoes were killed and analyzed for infection and viral spread by looking for the presence of virus in the midgut and the rest of the body, respectively. All mosquitoes had similar levels of virus in the midgut, whether they had received DVGs or not, suggesting that DVGs had no significant impact on infection. However, mosquitoes that had received DVGs had significantly lower levels of virus in the rest of the body compared to control mosquitoes, suggesting that DVGs can reduce replication and spread of virus in mosquitoes. Because all experiments involved delivery of DVGs before or concurrently with wild type virus infection, it is unclear whether DVGs would have any therapeutic effect if they were applied after infection. Presently, the most feasible use for DVGs would be as a vector control strategy by engineering and releasing mosquitoes that are unable to transmit virus. However, considering that DVGs have immunostimulatory potential and their presence in humans correlates with milder disease and better outcome after influenza virus, respiratory syncytial virus, hepatitis C virus, and dengue virus infections, it would be interesting to see if they could be applied as direct therapeutics in humans. Using a combination of lab experiments and computational approaches, Vignuzzi and colleagues identified DVGs with optimal interference activity in a follow-up study. Based on these results, the French biotechnology company Meletios Therapeutics is currently developing a new class of antivirals against Zika virus and Chikungunya virus. This is exciting news, because there are currently no effective antiviral treatments for these two viral infections, and I look forward to following up on these new developments in a future post. 3 thoughts on “Fighting Viruses with Viruses” Great information. Thanks for sharing with us. “Errors during viral replication” Thank you for the “zoom-in” on that replication process. I ran across another source of ‘mutation’ which might help us distinguish ‘chimeric’ data from what you described. That other source is the gathering of nucleotide data (It’s In The GenBank – 6). Pingback: Fighting Viruses with Viruses - darknight Comments are closed.
Earnings are the profits of a company. Earnings per share (EPS) is the figure on which corporate taxes are based. Many other technical terms are also used such as EBIT and EBITDA for an overview of certain aspects of corporate accounting. Basically, earnings refers to the profits a company makes from its activities. In this article we will discuss how to properly calculate earnings. The first step in accounting is to record all corporate revenue and expenses in terms of cash and assets, and then arrive at the gross revenue figure used to calculate the profit/loss of a company. The gross profit figure 1 is the total income obtained from all sources, which includes the sales of products/services/assets, the purchases of capital stock and payments of bank loans. The gross earnings figure 1 is calculated by adding the value of interests received on loans, equity securities, retained earnings, property and equipment, and other items that have a direct or indirect effect on a company’s profit. Net income, or income from operations less any amount deducted for expenses, represents the second step in accounting. Net income represents all cash flow from operations less any amount used for capital gains, capital repayments, and other payments. All expenses, net of receipts, are deducted before the final net income figure is produced. The difference between the gross income figure and the net income figure is the excess or loss. Any income or surplus over and above the initial balance that can be further used to reduce the loss or surplus is referred to as surplus income.
This lesson involves investigating chi-squared tests and distributions. Meaning of Power In this lesson, samples are generated from a population for a particular hypothesis test, leading to the conjecture that the null hypothesis is actually false. Type 2 Error This activity allows students to experiment with different alpha levels and alternative hypotheses to investigate the relationship among types of error and power. What is a p-value? This lesson involves beginning with a null hypothesis specifying the mean of a normally distributed population with a given standard deviation.
Atherosclerosis is a disease in which the arteries are narrowed due to a buildup of plaque. Arteries are the blood vessels that deliver oxygen and other important nutrients from your heart to the tissues of your body. As you get older, cholesterol, fats, and calcium can collect in your arteries and form plaque. It is difficult for blood to flow through your arteries because of the buildup of plaque. This buildup can happen in any artery in your body such as your legs, kidneys and heart. As a result, various tissues of your body may be short of blood and oxygen, and pieces of plaque may break off and cause a blood clot. If left untreated atherosclerosis can lead to heart failure, heart attack, or stroke. Atherosclerosis represents a common problem linked with aging. There are many treatment options to successfully prevent this condition. Did you know? Atherosclerosis is a type of arteriosclerosis which basically means hardening of the arteries. The two terms are sometimes used interchangeably. What causes atherosclerosis? Due to plaque buildup, arteries are getting harder and blood flow is restricted, which prevents your tissues and organs to get the oxygen-rich blood they need to function. The hardening of the arteries is caused by: Cholesterol is a yellow, waxy substance found in the body and in some foods you eat. Your arteries may be clogged if the levels of cholesterol in your blood are too high. It becomes a hard plaque that blocks the circulation of blood to your heart and other organs. - Dairy products low in fat - Whole grains - Skinned fish and poultry - A wide range of fruits and vegetables - Nuts and legumes - Non-tropical vegetable oils, like sunflower oil or regular oil. Some other diet tips: Avoid foods and beverages with added sugar, like candy, sugar-sweetened drinks, and desserts. The AHA recommends that women shouldn’t have more than 6 teaspoons or 100 calories of sugar a day, and men shouldn’t have more than 9 teaspoons or 150 calories a day. - Avoid high-sodium foods. It is advisable to have maximum around 2,300 milligrams (mg) of sodium per day. It would be ideally to consume no more than 1,500 mg a day - Avoid foods high in unhealthy fats like trans fats, and consider a better option like unsaturated fats. You may have to reduce saturated fat to no more than 5 to 6 percent of total calories if you want to lower your blood cholesterol. For someone who consumes around 2,000 calories a day, that’s 13 grams of saturated fat. Your heart and blood vessels have to work harder in order to pump and receive blood as you age. Your arteries may become weaker and less elastic, and as a result – more susceptible to plaque buildup. Who’s at risk for atherosclerosis? There are various factors that put you at risk for atherosclerosis. Some risk factors can be modified, while others cannot be modified. If your family members have atherosclerosis, chances are you may be at risk for hardening of the arteries. Certain heart-related problems, including this condition, may be inherited. Lack of exercise Exercising regularly is good for your heart. It keeps your heart muscle strong and encourages oxygen-rich blood to flow throughout your body. If you don’t exercise often, and spend a lot of time seated and inactive, the risk of a medical condition such as a heart disease is increased. High blood pressure High blood pressure can damage your blood vessels by weakening them in some areas. The flexibility of your arteries may also be compromised over time, if you have cholesterol or other substances in your blood. Smoking tobacco products can damage your heart and blood vessels. People who have diabetes also have a higher incidence of coronary artery disease (CAD). What are some of the symptoms of atherosclerosis? Most of the symptoms of atherosclerosis won’t show up until a blockage happens. Some of the most common symptoms are: - Angina or chest pain - Pain in your arm, leg, and anywhere else that has a blocked artery - Shortness of breath - Confusion, which happens if the blockage affects blood circulation to your brain - Muscle weakness in your legs from lack of circulation It is very important to recognize the symptoms of stroke and heart attack. Both can be caused by atherosclerosis and require immediate medical attention. The symptoms of a heart attack are the following: - Discomfort or chest pain - Pain in the back, neck, jaw, shoulders and arms - Shortness of breath - Abdominal pain - A sense of impending doom - Nausea or vomiting The symptoms of a stroke are the following: - Trouble to speak - Trouble to understand speech - Loss of balance - Weakness or numbness in the face or limbs - Problems with vision - Sudden, severe headache Stroke and heart attack are both medical emergencies, and if you experience symptoms of a heart attack or stroke, immediately call 911 or your local emergency services in order to get to a hospital’s emergency room as soon as possible. How is atherosclerosis diagnosed? If you have symptoms of atherosclerosis, your doctor will perform a physical exam and will check for: - Slow healing of wounds, which means that blood flow is restricted - A weakened pulse - An aneurysm, an abnormal widening or bulging of an artery due to weakness of the arterial wall A cardiologist can check out for any abnormal sounds by listening to your heart. If they hear a whooshing noise, it means that an artery is blocked. Your doctor will certainly order more tests if they think you have atherosclerosis. The tests may include: - A blood test to check your cholesterol levels - A Doppler ultrasound, which uses sound waves in order to create a picture of the artery that shows if there are any blockages - An ankle-brachial index (ABI), which looks for a blockage in your legs or arms by comparing the blood pressure in each limb - A stress test, or exercise tolerance test, which monitors your blood pressure and heart rate while you exercise on a stationary bicycle or treadmill - An electrocardiogram (ECG or EKG), which measures your heart’s electrical activity in order to look for any areas of decreased blood flow - A cardiac angiogram, which is a type of chest X-ray that’s taken after radioactive dye is injected in your heart arteries - A magnetic resonance angiography (MRA) or a computed tomography angiography (CTA) to create pictures of the large arteries in your body How can atherosclerosis be treated? Treatment involves decreasing the amount of cholesterol and fat you consume, along with making some lifestyle changes. In order to improve the health of your blood vessels and heart, you should also exercise more regularly. Your doctor may recommend you to make some lifestyle changes if your cholesterol is not severe. You can also need medications or surgery as additional medical treatments. Taking medicine can prevent your atherosclerosis from worsening. Medications for treating atherosclerosis include: - Statins and fibrates are medications that can lower your cholesterol - Calcium channel blockers or beta-blockers to lower your blood pressure - Angiotensin-converting enzyme (ACE) inhibitors are capable of preventing the narrowing of your arteries - Diuretics or water pills can help to lower your blood pressure - Anticoagulants and antiplatelet drugs like aspirin can prevent blood from clogging and clotting your arteries If you have a history of atherosclerotic cardiovascular disease (e.g., stroke and heart attack) aspirin can be particularly effective. An aspirin regimen can lower your risk of having another health issue. If you don’t have a history of atherosclerosis, it is advisable to use aspirin as a preventive medication if your risk of atherosclerosis is high and our risk of bleeding is low. Surgery may be necessary if your skin or muscle is endangered or your symptoms are severe. Types of surgeries you may need to treat atherosclerosis include: - Bypass surgery, which means that a vessel from somewhere else will have to be used in your body, or a synthetic tube in order to divert blood around your narrowed or blocked artery - Angioplasty involves a catheter and a balloon to expand your artery, or in some cases, stent has to be inserted to leave the artery open - Thrombolyc therapy, which means that a drug into your affected artery has to be injected in order to dissolve a blood clot - Atherectomy involves removing plaque from your artheries by using a catheter with a sharp blade at one end - Endarterectomy means that your fatty deposits have to be surgically removed from your artery What to expect in the long run? With time, you may see improvement in your health after you receive treatment. The success of your treatment will depend on: - How severe is your condition - Whether other organs were affected - How promptly it was treated It is not possible to reverse the hardening of the arteries. However, treating the underlying cause and making dietary and lifestyle changes can prevent or slow down the process from getting worse. In order to make the appropriate healthy lifestyle changes you should work closely with your doctor. You’ll also need to take the proper medications in order to avoid complications and have your condition under control. What complications are associated with atherosclerosis? Atherosclerosis can cause: - Heart attack - Heart failure - Abnormal heart rhythm Atherosclerosis is also associated with: Coronary artery disease (CAD) The coronary arteries are blood vessels that provide your heart with oxygen-rich blood. Coronary artery disease (CAD) happens when the coronary arteries become hard. Carotid artery disease The carotid arteries which supply blood to your brain are found in your neck. If plaque builds up in their walls these arteries may be compromised. The lack of circulation may reduce how much oxygen and blood reaches your brain’s tissue and cells. Learn more about carotid artery disease. Peripheral artery disease Your arms, legs, and lower body depend on your arteries to supply oxygen-rich blood to their tissues. Circulation problems in these areas of the body may occur if arteries are hardened. Blood is supplied to your kidneys through the renal arteries. Kidneys filter extra water and waste products from your blood. Atherosclerosis of these arteries may result in kidney failure. Which lifestyle changes can help to prevent and treat atherosclerosis? Lifestyle changes can help to treat and treat atherosclerosis, especially for people who have type 2 diabetes. Here are some helpful lifestyle changes: - Avoid fatty foods - Add fish to your diet, at least twice per week - Eat a healthy diet low in cholesterol and saturated fat - Get at least 75 minutes of vigorous exercise or 150 minutes of moderate exercise each week - Manage stress - Quit smoking, if you’re a smoker - Lose weight if you’re obese or overweight - Treat conditions associated with atherosclerosis such as diabetes, hypertension and high cholesterol We can Help! Our local advisors can help your family make a confident decision about senior living.
Vive le français Oh là, là, c’est magnifique La langue de l’amour ! Learning a language enables students to become global citizens. It enhances literacy and the full complement of learning and social skills – it builds bridges of knowledge, respect and empathy. NB: In Grade 7 all students will study French for half of the year. In Grades 8-10, French becomes an Optional subject. Through studying French, students will be able to: - Use French to communicate with others in authentic situations - Understand French as a system - Understand and appreciate the cultural context in which French is used - Make connections between English and French - There will be a focus on developing: - Pronunciation, intonation, stress patterns and accents - Speaking and listening for particular purposes - Key sentence structures and grammatical forms - Key communicative functions for exchanging information, expressing attitudes and opinions, getting things done - A repertoire of communicative references to events, time, quantity, colour, size and value.
On this page... Effects of elevated carbon dioxide on reef fishes Rising levels of carbon dioxide in the atmosphere means that more CO2 dissolves into the oceans, making it more acidic. Much pioneering research has been done at LIRS in recent years to determine the effect of that different water chemistry on reef fishes. At ocean pH levels predicted for the end of this century, researchers have found that the behaviour of reef fishes changes in many ways - for example, they are attracted to the smell of predators rather than repelled by it. This paper provides a good summary of the research to date while rigorously testing the methodology used for those earlier studies: Munday, P.L., M.J. Welch, B.J.M. Allan, S.-A. Watson, S.J. McMahon and M.I. McCormick, 2016. Effects of elevated CO2 on predator avoidance behaviour by reef fishes is not altered by experimental test water. PeerJ 4:e2501; DOI 10.7717/peerj.2501 Crown-of-Thorns Starfish can really see Crown-of-Thorns Starfish (COTS) are voracious coral predators that are being culled on the Great Barrier Reef to protect corals. By understanding how these starfish sense their environment to find their coral prey, we may be able to develop better methods for controlling them. It has long been known that starfish can detect light using an 'eye-spot' at the end of each arm but true image-forming vision had not been known to exist. The study described in the publication below used a combination of aquarium and field studies to show that COTS can actually form images. The authors suggest that COTS use smell to find their prey from a distance, then switch to visual as they get closer and the smell becomes less directional. Petie, R., A. Garm and M.R. Hall, 2016. Crown-of-thorns starfish have true image forming vision. Frontiers in Zoology, 13: 41.
General Adaptation Syndrome (GAS) can be applied to any physiological function under stress. Physiologists define stress as how the body reacts to a stressor, real or imagined, a stimulus that causes stress. 1. Alarm is the first stage. When the threat or stressor is identified or realized, the body’s stress response is a state of alarm. 2. Resistance (or adaptation) is the second stage. If the stressor persists, it becomes necessary to attempt some means of coping with the stress. Although the body begins to try to adapt to the strains or demands of the environment, the body cannot keep this up indefinitely, so its resources are gradually depleted. 3. Exhaustion is the third and final stage in the GAS model. At this point, all of the body’s resources are eventually depleted and the body is unable to maintain normal function. Generally, if the stimulus is too little, the body does not go through an adaptation, and if the stimulus is too much for the adaptation stage to complete, exhaustion sets in. Adapting to poly-sleep requires: 1. a stressor. This is sleep deprivation we want enough sleep deprivation (usually 24h awake) to stimulate; 2. an adaptation. This requires a circadian rhythm change, and a sleep-stage repartition will occur in some schedules. 3. hopefully exhaustion is never reached, as it implies a failure to adapt to the schedule. One of the most tried and tested ways to adapt to a stressor is to increase the frequency of exposure of the stressor to an optimal rate the body can handle. This optimal frequency for adapting to a sleep schedule is usually much more often than the frequency of periods of sleep in the desired schedule.
Long tree-ring sequences have been developed throughout the world and can be used to check and calibrate radiocarbon dates. An extensive tree-ring sequence from the present to 6700 BC was developed in Arizona using California bristlecone pine (), some of which are 4900 years old, making them the oldest living things on earth. There are two techniques for dating in archaeological sites: relative and absolute dating. How It Works: Carbon has 3 isotopic forms: Carbon-12, Carbon-13, and Carbon-14. The numbers refer to the atomic weight, so Carbon-12 has 6 protons and 6 neutrons, Carbon-13 has 6 protons and 7 neutrons, and Carbon-14 has 6 protons and 8 neutrons. Limitations and calibration: When Libby was first determining radiocarbon dates, he found that before 1000 BC his dates were earlier than calendar dates. He had assumed that amounts of Carbon-14 in the atmosphere had remained constant through time. The Mayan calendar used 3114 BC as their reference. More recently is the radiocarbon date of 1950 AD or before present, BP. In a stratigraphical context objects closer to the surface are more recent in time relative to items deeper in the ground. Although relative dating can work well in certain areas, several problems arise. Absolute dating represents the absolute age of the sample before the present. Historical documents and calendars can be used to find such absolute dates; however, when working in a site without such documents, it is hard for absolute dates to be determined. As long as there is organic material present, radiocarbon dating is a universal dating technique that can be applied anywhere in the world.
One of the great discoveries of modern medicine was the invention of antibiotics. These kill bacteria and can cure life-threatening infectious diseases such as pneumonia, for which no effective treatment was previously available. But the misuse of antibiotics means that increasing numbers of bacteria are becoming immune to this type of medication. So it is particularly important that they are used correctly. Antibiotics can save lives but they also alleviate bacterial infection symptoms and allow us to recover faster. But antibiotic treatment has side effects, as well. Of example, nausea or diarrhea are normal. Antibiotics are also used far too often and there is systematic abuse of them. This caused several different types of bacteria to become antibiotic resistant (unresponsive). Since tolerance has become more common, many illnesses in the past can not be treated as well as they could. It is important to know the following things when using antibiotics to prevent resistance and side effects: - Antibiotics only work against bacteria. Many infections are caused by viruses and can’t be treated using antibiotics – examples include respiratory illnesses such as a cough, stuffy nose, bronchitis or the flu. - Excessive and improper use of antibiotics is causing side effects and reducing their efficacy in the long term. What is antibiotic resistance? Bacteria and other germs are said to be immune in medicine if they can especially tolerate exposure to external influences. For example, stomach (gastric) acid destroys most of the germs that reach the stomach with food. But some bacteria have a mucous coating which protects them from the acid. We are gastric acid resistant. Antibiotic resistance operates on a similar principle: The bacteria have acquired a new property that protects them against the antibiotics. For example, certain types of bacteria may create a substance that makes certain antibiotics ineffective. The word “multiresistant” refers to bacteria which can defend themselves from several different antibiotics. What causes resistance? Many of the now resistant bacteria used to be susceptible to antibiotics. There are a few innovations in that that have played a role. To put it briefly, originally one type of antibiotic could neutralize a certain type of bacteria and then effectively stop the infection. But the bacteria’s genetic material may change by chance, producing often new properties. If the bacteria are safe against an antibiotic then the bacteria have become immune. Such types of properties can also move from one bacteria group to another. If antibiotics are used more often, resistant bacteria are better able to reproduce because the other non-resistant bacterial strains are prevented. Antibiotics then no longer help against resistant bacteria-infections. Which bacteria are antibiotic resistant, and why they are dangerous? Streptococcus strains and bacteria Staphylococcus also resist antibiotics. Another example is named “the Staphylococcus aureus resistant to methicillin” (MRSA).Staphylococci can be found on skin and mucous membranes, and can cause infection, for example when they get into open wounds. Many types of bacteria have now established resistant strains, such as Escherichia coli, Klebsiella and pseudomonads. What is being done about antibiotic resistance? Antibiotics are prescription-only in Germany. This means that the primary responsibility for diligent and accurate use rests with the physicians. They must first see if somebody has a bacterial infection actually. If they do, then it is important that the antibiotic is administered at the right dose and for long enough, and that the right antibiotic is chosen which will combat the bacteria most effectively. Hygiene laws are also in place to keep resistant bacteria from further spreading and preventable infections from occurring. Inside a hospital these steps are especially important. Antibiotics are used relatively frequently there, which means that resistant germs can grow very quickly. When you come into contact with someone who has a resistant bacteria infection, it can help you wear disposable gloves, mask and hat, and use a hand disinfectant to avoid the germ spreading. Antibiotics are also used in both veterinary and herbal medicine. Veterinarians also need to stick strictly to the antibiotic handling guidelines. What can I do to prevent antibiotic resistance? Being cautious when taking antibiotics can help both prevent antibiotic resistance as well as side effects. The most important thing is not to overestimate what antibiotics can do: patients often expect to receive antibiotic prescriptions for treating medical conditions for which they are not qualified. Antibiotics are needed to treat serious bacterial infections such as lung infections or meningitis (inflammation of the brain and spinal cord lining membranes). This is not the case when, for example, people who are otherwise healthy have virus-caused respiratory infections, such as cold or influenza (“flu”). Antibiotics are typically of no use, as they only kill bacteria. Antibiotics also have side effects that include allergic reactions, issues with the stomach and intestines, diarrhea and fungal infections. Because of these associated risks, careful consideration of the benefits and disadvantages of taking antibiotics is important. What’s important to consider when taking antibiotics? Antibiotics should be used, as long as they are approved by the doctor. Just because the disease’s symptoms subside, it doesn’t mean that all of the germs were destroyed. Remaining bacteria may cause the disease to begin again. If some tablets are left over, they should not be retained or given to others for later use. The residual prescription may be disposed of in the ordinary garbage or dropped off at some pharmacies. Nevertheless, pharmacies are not obliged to accept open medicine. It is critical that the drug is not disposed of by pouring it down the drain or flushing it down the toilet. That’s bad for the environment and it also leads to resistance to bacteria. Medicines can only function correctly if they are used correctly. The following things are important to learn when taking antibiotics: Can the tablets be broken into smaller pieces to allow them to swallow more easily? Doing so can stop those drugs from working properly. What food do you take with antibiotics? Antibiotics are usually taken with water, because it can influence how the body absorbs certain medications together with fruit juices, dairy products or alcohol. Dairy products include butter, milk, yogurt, and cheese. You may need to wait for up to three hours after taking an antibiotic before eating or drinking any dairy products. Grapefruit juice and dietary supplements which contain minerals such as calcium may also function to dampen the antibiotic effect. When should you take antibiotics? Many antibiotics should always be administered at the same time of the day; others should be taken before, during or after a meal. Of example, if you are supposed to take the medication three times a day, it typically needs to be taken at fixed times to distribute the effect equally over the course of the day. You will remember the 6 a.m., 2 p.m. regular times And 10:00 p.m. For example, for an antibiotic which needs to be taken every 8 hours. Could you mix antibiotics with other medications? Because antibiotics can interfere with other medicines, it is important to tell your doctor if you are taking other medicines, too. For example, antibiotics may interfere with certain thinners in the blood and with antacids. Some antibiotics may be less effective in making birth control pills. Detailed information regarding the use of a specific antibiotic can be found in the package insert. If you’re not sure what to consider when taking the antibiotic, ask your doctor or pharmacist. Federal Ministry of Health (BMG), Federal Ministry of Food and Agriculture (BMEL), Federal Ministry of Education and Science (BMBF). DART 2020. Zwischenbericht anlässlich der WHA 2016. May 2016. Centers for Disease Control and Prevention (CDC). Antibiotic / Antimicrobial Resistance. June 12, 2017. Deutsche Gesellschaft für Infektiologie e.V. (DGI). S3-Leitlinie: Strategien zur Sicherung rationaler Antibiotika-Anwendung im Krankenhaus. AWMF-Register-Nr.: 092-001. December 15, 2013. Kayser FH, Böttger EC, Haller O, Roers A, Deplazes P. Taschenlehrbuch Medizinische Mikrobiologie. Stuttgart: Thieme; 2014. Weltgesundheitsorganisation (WHO). Antimicrobial resistance. October 2016. IQWiG health information is written to help people understand the benefits and drawbacks of key treatment options and health care services. Because IQWiG is a German institute, some of the information provided here is unique to the health care system in Germany. In an individual case the suitability of any of the options described may be determined by talking to a doctor. Our information is based upon the results of studies of good quality. It is written and reviewed by qualified experts by a team of healthcare professionals, scientists, and editors. You will find in our methods a detailed description of how our health information is produced and modified.
1. What are slack, surplus, and artificial variables? When is each used and why? 2. Discuss the similarities and differences between minimization and maximization problems using the graphical solution approaches of linear programming.© BrainMass Inc. brainmass.com October 10, 2019, 3:19 am ad1c9bdddf Slack, Surplus and Artificial Variables A slack variable is a variable that is added to inequality equation constraints with less than or equal to signs changing them into equalities. Introducing a slack variable to an inequality constraint transforms the inequality into a non-negativity equality constraint and is, in most cases, required to be a positive value. This variable is often used when working out inequalities using simplex method to determine optimum values, and is often applied less than or equal to inequalities (Arsham, 1997). A surplus variable on the other hand is a variable that transforms a greater than or equal to inequality constraint in to equality constraints and is often in most cases a negative value. Introducing a surplus variable to an inequality constraint often transforms it into ... This solution explains the conceps of surplus, slack and artificial variables. Additionally, this solution compares and contrasts minimization and maximization problems using the graphical solution approaches of linear programming.
The Liao dynasty (//; Khitan: Mos Jælud; simplified Chinese: 辽朝; traditional Chinese: 遼朝; pinyin: Liáo cháo), also known as the Liao Empire, officially the Great Liao (simplified Chinese: 大辽; traditional Chinese: 大遼; pinyin: Dà Liáo), or the Khitan Empire (Khitan: Mos diau-d kitai huldʒi gur}}),, was an empire in East Asia that ruled from 907 to 1125 over present-day Mongolia and portions of the Russian Far East, northern China, and northeastern Korea. The empire was founded by Abaoji, Khagan of the Khitan people around the time of the collapse of Tang China and was the first state to control all of Manchuria. Almost immediately after its founding, the Khitan Empire began a process of territorial expansion, with Abaoji leading a successful conquest of Balhae. Later emperors would gain the Sixteen Prefectures by fueling a proxy war that led to the collapse of the Later Tang (923–936) and would establish tributary relationships with Goryeo and Northern Song after failing to conquer Goryeo. Tension between traditional Khitan social and political practices and Chinese influence and customs was a defining feature of the dynasty. This tension led to a series of succession crises; Liao emperors favored the Chinese concept of primogeniture, while much of the rest of the Khitan elite supported the traditional method of succession by the strongest candidate. So different were Khitan and Chinese practices that Abaoji set up two parallel governments. The Northern Administration governed Khitan areas following traditional Khitan practices, while the Southern Administration governed areas with large non-Khitan populations, adopting traditional Chinese governmental practices. Differences between Chinese and Khitan society included gender roles and marital practices: the Khitans took a more egalitarian view towards gender, in sharp contrast to Chinese cultural practices that segregated men's and women's roles. Khitan women were taught to hunt, managed family property, and held military posts. Many marriages were not arranged, women were not required to be virgins at their first marriage, and women had the right to divorce and remarry. The Liao dynasty was destroyed by the Jurchen people of the Jin dynasty in 1125 with the capture of Emperor Tianzuo of Liao. However, the remnant Khitan, led by Yelü Dashi, established the Qara Khitai (Western Liao dynasty), which ruled over parts of Central Asia for almost a century before being conquered by the Mongols. Although cultural achievements associated with the Liao dynasty are considerable, and a number of various statuary and other artifacts exist in museums and other collections, major questions remain over the exact nature and extent of the influence of the Liao Khitan culture upon subsequent developments, such as the musical and theatrical arts. The Liao dynasty was officially known as the Khitan (now known as Cathay) or Khitan state in 916. The name "Great Liao" began to appear as the country name between 936 and 947. The dynasty name "Liao" refers to the Liao River in southern Manchuria, the traditional Khitan homeland. Since 983, the state became again known as the Khitan, but "Great Liao" reappeared as the country name in 1066, which lasted until the end of the dynasty. Neither the origins, ethnic makeup, nor early history of the Khitans are well documented in historical records. The earliest reference to a Khitan state is found in the Book of Wei, a history of the Northern Wei Dynasty (386–534) that was completed in 554. Several books written after 554 mention the Khitans as being active during the late third and early fourth centuries. The Book of Jin (648), a history of the Jin dynasty (265–420), refers to the Khitans in the section covering the reign of Murong Sheng (398–401). Samguk Sagi (1145), a history of the Three Kingdoms of Korea, mentions a Khitan raid taking place in 378. According to sinologists Denis C. Twitchett and Klaus-Peter Tietze, it is generally held that the Khitans emerged from the Yuwen branch of the Xianbei people. Following a defeat at the hands of another branch of the Xianbei in 345, the Yuwen split into three tribes, one of which was called the Kumo Xi. In 388 the Kumo Xi itself split, with one group remaining under the name Kumo Xi and the other group becoming the Khitans. This view is partially backed up by the Book of Wei, which describes the Khitans as being of Xianbei origins. There are also several competing theories on the origin of the Khitans. Beginning in the Song dynasty, some Chinese scholars suggested that the Khitans might have descended from the Xiongnu people. While modern historians have rejected the idea that the Khitan were solely Xiongnu in origin, there is some support for the claim that they are of mixed Xianbei and Xiongnu origin. Beginning with Rashid-al-Din Hamadani in the fourteenth century, several Western scholars have theorized that the Khitans were Mongolic in origin, and in the late 19th century Western scholars made the claim that the Khitans were Tungusic in origin—modern linguistic analysis has discredited this claim. By the time the Book of Wei was written in 554, the Khitans had formed a state in what is now China's Jilin and Liaoning Provinces. The Khitans suffered a series of military defeats to other nomadic groups in the region, as well as to the Chinese Northern Qi (550-577) and Sui (589-618) Dynasties. Khitan tribes at various times fell under the influence of Turkic tribes such as the Uighurs and Chinese dynasties such as the Sui and Tang. This influence would significantly shape Khitan language and culture. In the Suishu (Book of Sui, Volume 84) the Khitan are described as "bellicose in plundering and raiding borders" and "the most uncourteous and arrogant among all barbarians". The Liaoshi (LS, vol. 32 and 59) gives the following account of the early Khitan: Residing in the Great Desert (大漠 - dàmò), where there is much cold and much wind, they had livestock tending and fishing as food source, fur as dress and migrated with the seasons. Their specialty was carts and horses...In the old Khitan custom, their wealth was horses, their strength was soldiers. Horses were released all through the open country and demobilized soldiers were spread throughout the people. When a matter of importance or battle arose they were called to arms. If the order was given at 5am they would all assemble forthwith at 7am. Horses followed water and grass. People relied on milk and kumiss. They bent the powerful bow and shot animals for their daily use. They had dried food and fodder. This was their Way (道 - dào). On account of this they maintain victory and wherever they look they encounter no opposition. These are the ancient eight tribes: the Xiwandan tribe, the Hedahe tribe, the Fufuyu tribe, the Yuling tribe, the Nilin tribe, the Pixie tribe, the Li (Black) tribe, the Tuliuyu tribe...Soon after increasing in population they invaded the Northern Qi (北齊 - Běi Qí) but lost a hundred thousand people to captivity. Then, being pressed by the Turks (突厥 - Tūjué), they temporarily resided in Korea (高麗 - Gāolí) numbering not much more than ten thousand families. The tribes became scattered and were no longer the eight tribes of old. For most of the century between 630 and 730, the Khitans were under the influence of the Tang dynasty. The arrangement was largely the doing of the Khitan Dahe clan. The Tang emperor bestowed the Chinese surname Li on the Dahe and appointed their leader to a governorship that Twitchett and Tietze described as "an office specifically created for the indirect management of the Khitan tribes". Towards the turn of the century, however, Tang control of the north began to slip as it focused attention on its other borders. In 696 the Dahe leader, Li Jinzhong, launched a rebellion and led Khitan forces into Hebei. Although the rebellion was defeated, it took over fifteen years before the Tang were able to reassert control over the Khitans, and that control would never be strong or long-lived. Re-disintegration of Khitan-Liao relations in the 730s saw the Yaolian clan replace the Dahe as the Khitan ruling clan, forcing Tang governor An Lushan to launch two invasions into Khitan territory in 751 and 755. After being soundly defeated by the Khitans during the first invasion, An Lushan was successful in the second, but he then led a rebellion against the Tang that included Khitan troops in his army. The An Lushan Rebellion marked the beginning of the end of the Tang dynasty. Following the An Lushan Rebellion, the Khitans became vassals of the Uighurs, while simultaneously paying tributes to the Tang, a situation that lasted from 755 until the fall of the Uighurs in 840. From 840 until the rise of Abaoji, the Khitans remained a tributary of the Tang dynasty. Abaoji, who later became Emperor Taizu of Liao, was born in 872, the son of the chief of the Yila tribe. At that time, the Yila tribe was the largest and strongest of the eight affiliated Khitan tribes; however, the Great Khan, the overall leader of the Khitans, was drawn from the Yaolian lineage. In 901 Abaoji was elected to be the chief of the Yila tribe by its tribal council. By 903, Abaoji had been named the Yüyue, the overall military leader of the Khitans, subordinate only to the Great Khan. Four years later, in 907, Abaoji became the Great Khan of the Khitans, ending nine generations of Yaolian rule. Abaoji acquired the prestige needed to secure the position of Khitan Great Khan through a combination of effective diplomacy and a series of successful military campaigns, beginning in 901, against the Han Chinese forces to the south, the Xi and Shiwei to the west, and the Jurchens in the east. The same year that Abaoji became Great Khan, the Chinese warlord Zhu Wen, who in 904 had murdered the last legitimate emperor of the Tang dynasty, declared the Tang over and named himself emperor of China. His dynasty dissolved quickly, ushering in the fifty-three-year period of disunity known as the Five Dynasties period. One of the five dynasties, the Later Jin (936–947), was a client state of the Khitans. For much of Chinese history, the position of Emperor was determined by primogeniture; the position would pass from father to first-born son upon the father's death. While Khitan succession was also kept within families, an emphasis was placed on selecting the most capable option, with all of a leader's brothers, nephews, and sons considered valid choices for succession. Khitan rulers were expected to hand over power to a paternal relative after serving a single three-year term. Abaoji signaled his desire to become a permanent ruler at his accession in 907, securing his position by killing most of the other Khitan chieftains. Between 907 and 910 Abaoji's rule went unchallenged. It was only after 910, when Abaoji disregarded the Khitan tradition that another member of the family assume the position of Great Khan, that his rule came under direct challenge. In both 912 and 913 members of Abaoji's family, including most of his brothers, attempted armed insurrections. After the first insurrection was discovered and defeated, Abaoji pardoned the conspirators. After the second, only his brothers were pardoned, with the other conspirators suffering violent deaths. The brothers plotted additional rebellions in 917 and 918, both of which were easily crushed. In 916, at what would have been the end of his third term as Khitan Grand Khan, Abaoji made a number of changes moving the Khitan state closer to the model of governance used by the Chinese dynasties. He assumed the title of Celestial Emperor and designated an era name, named his oldest son Yelü Bei as his successor, and commissioned the construction of a Confucian temple. Two years later he established a capital city, Shangjing (上京), which imitated the model of a Chinese capital city. Before his death in 926, Abaoji greatly expanded the areas that the Khitans controlled. At its height, the Liao dynasty encompassed modern-day Mongolia, parts of Kazakhstan and the Russian Far East, and the Chinese provinces of Hebei, Heilongjiang, Inner Mongolia, Jilin, Liaoning, and Shanxi. In 916 Emperor Taizu (Abaoji) officially designated his eldest son, Yelü Bei, as his successor. Succession by primogeniture was a long-held standard in Chinese culture but was not accepted among the Khitans, creating a friction between Taizu's desires and the beliefs of the Khitan elites, including Taizu's wife, Empress Shulü Ping. Taizu, sensing the possibility that the succession process would run into difficulty, forced the Khitan leadership to swear allegiance to Yelü Bei after he was installed as heir apparent. To the Khitans, this was considered a radical move. This friction between primogeniture and succession by the strongest candidate would lead to repeated succession crises, the first of which occurred after Taizu's sudden and unexpected death in 926. Yelü Bei was twenty-six years old at the time of his father's death. A polymath, Bei exemplified many of the values of the Chinese aristocracy; he was an expert in music, medicine, fortune-telling, painting, and writing (in both Chinese and Khitan). He was also an accomplished warrior, leading troops into battle during his father's conquest of Balhae. After the campaign ended in victory for the Liao in 926, Emperor Taizu gave Bei command of the conquered territory––which became known as the principality of Dongdan––as well as the title of Prince of Dongdan. Empress Shulü Ping, who became known as Empress Dowager Yingtian following the death of her husband, was an exceptionally powerful figure both before and after Taizu's death. While the latter was alive, Shulü Ping commanded an army of 200,000 horsemen that was tasked with maintaining order while Taizu led military campaigns abroad. She also led campaigns herself. Following the death of her husband, the Empress rejected the traditional Khitan custom of being buried with him, and elected to cut off her right hand and bury that with the Emperor instead. Shulü Ping then seized full military and civil authority in order to oversee the imperial succession under her own terms. The Empress's refusal to kill herself and be buried with Taizu effectively ended the longstanding custom. Precisely because Prince Yelü Bei exemplified both Chinese and Khitan values, Empress Shulü Ping objected to Bei assuming the role of Emperor. The Empress believed that Bei's openness to Chinese culture detracted from his leadership ability as a Khitan, and she instead favored Emperor Taizu's more traditionalist second son, Yelü Deguang. Deguang enjoyed not only the support of his mother, but also of the Khitan nobility. Realizing that he could not assume the throne, and that it would be dangerous to try, Bei campaigned in favor of allowing his younger brother to assume the throne, and by the end of 927, formally stated to his mother that Deguang's qualifications were superior to his own, functionally ending his ability to challenge Deguang's ascension to the throne. Despite Bei voluntarily relinquishing his claim, Deguang, who had assumed the title of Emperor Taizong of Liao, viewed Bei as a threat. Bei still held the role of Prince of Dongdan, and moved back there after relinquishing his imperial claim. In order to break any potential power base Bei might form in Dongdan, Emperor Taizong ordered that the capital of Dongdan and all of its people move to what is now Liaoyang. Prince Bei himself was placed under surveillance by the Emperor. In 930 Prince Bei fled to the Later Tang, where he became an honored guest of Emperor Mingzong, who went as far as to bestow upon Prince Bei the Emperor's own surname of Li (李). There are two conflicting accounts of Prince Bei's death: he was assassinated either in 936 by Emperor Mo of Later Tang in retaliation for the Khitans' support in overthrowing the Tang and replacing it with the Later Jin, or in 937 by Emperor Gaozu of Later Jin (Shi Jingtang) as a show of loyalty to Emperor Taizong of Liao. After Emperor Mingzong died in 933, the Later Tang began to crumble from its own succession crisis. Mingzong's son and successor Li Conghou ruled for only five months before he was killed in 934 in a coup led by his adoptive brother Li Congke (Emperor Mo of Later Tang). Prince Bei, who was still an honored guest at the Tang court at the time, wrote to his brother Emperor Taizong (Yelü Deguang), advising him to invade the Tang. Instead, Taizong lent military support to a rebellion led by Shi Jingtang, a Tang governor and son-in-law of the former Emperor Mingzong. With Khitan help, in 936 Shi Jingtang succeeded in replacing the Later Tang with his own Later Jin. After some negotiation with the more powerful Khitans, he ceded sixteen border prefectures stretching from modern-day Datong (Shanxi province) to the coast of the Bohai Sea east of what is now Beijing, to the Liao. Since the Sixteen Prefectures contained numerous strategic passes and fortifications, the Khitans now had unrestricted access to the plains of northern China. Shi Jingtang also agreed to treat Emperor Taizong of Liao as his own father, a move that symbolically elevated Taizong and the Liao to a superior position. The relationship between the Liao and the Later Jin soured after the death of Shi Jingtang in 942 and the elevation to the throne of Shi Chonggui, also known as Emperor Chudi of Later Jin. The new emperor surrounded himself with anti-Khitan advisers, and in 943 he expelled the Liao envoy from the Jin capital of Kaifeng and seized the property owned by Khitan merchants in the city. By the end of the following year Emperor Taizong had launched an invasion of the Jin. Although the invasion took three years and the Liao faced several setbacks, by the end of 946 Emperor Taizong had secured the surrender of the head of the Later Jin forces and was able to march into Kaifeng unopposed. Emperor Taizong celebrated his victory with the adoption of the dynastic name "Greater Liao". The invading Liao forces, who had not brought adequate supplies for their invasion, began looting the newly conquered territory and imposed high taxes on the ethnic Chinese population in the formerly Jin lands. This sparked a series of rebellions that culminated in 947 with the establishment of the Later Han by the former Jin governor Liu Zhiyuan. After occupying Kaifeng for only three months, Emperor Taizong and the Liao were forced to retreat north. During the retreat Emperor Taizong died of a sudden illness, just south of modern-day Shijiazhuang, Hebei. The death of Taizong set up a second succession crisis, again instigated by Empress Dowager Yingtian and fueled by the conflict between Chinese primogeniture and Khitan succession customs. Yelü Ruan, oldest son of Prince Bei and nephew of Emperor Taizong, proclaimed himself Emperor while still in Hebei. Emperor Taizong raised Yelü Ruan, following Yelü Bei's departure for the Later Tang, and the relationship between uncle and nephew was close. Yelü Ruan accompanied the emperor during his invasion of the Later Jin, and he earned the reputation as a capable warrior and commander, and as one of courteous and noble-minded disposition. Empress Dowager Yingtian supported Emperor Taizong's younger brother, Yelü Lihu, for the throne instead. The Empress Dowager sent two successive armies to face Yelü Ruan, who defeated them both. Ultimately Lihu, who the Khitan nobility viewed as cruel and spoiled, was unable to gain enough support to further challenge Yelü Ruan, and after a peace was brokered by a cousin of the Yelü clan, Yelü Ruan formally assumed the role of emperor and the title of Emperor Shizong of Liao. Emperor Shizong promptly exiled both Empress Dowager Yingtian and Yelü Lihu from the capital, ending their political ambitions. Emperor Shizong's rule would be characterized by a series of rebellions from within his extended family. Although he would rule for only four years before being killed in 951 in a rebellion led by one of his nephews, Emperor Shizong oversaw a refinement of his grandfather's dual system of government, which brought the structure of the Southern Administration closer to the model used by the Tang dynasty. Emperor Shizong would be succeeded by Emperor Taizong's son Yelü Jing, also known as Emperor Muzong of Liao. Emperor Muzong, who died in 969, would be the second and the last of the emperors to succeed Abaoji who was not a direct descendant of Yelü Bei. The reign of Emperor Shengzong from 982 to 1031 represented the height of the Liao dynasty's power. Shengzong oversaw a successful military campaign against the Song dynasty which secured a long-term peace agreement with terms favorable to the Liao. He also oversaw a failed military campaign against the Korean Goryeo Dynasty. In 990 Liao emperor recognizes a "king of Xia" for Li yuanhao. When Abaoji conquered the Balhae state in 926, most of the population was relocated to what is now Liaoning, China. At least three groups remained in the former Balhae territory, one of which formed the state of Ding'an. Despite launching two invasions, in 975 and 985, the Liao forces were unable to defeat the Ding'an. Unable to eliminate the threat, and weary of Jurchen groups also inhabiting the region, the Liao established three forts with military colonies in the Yalu River valley area. With military action in close proximity to Goryeo territory, coupled with a cancelled Liao invasion of Goryeo in 947 and a strong diplomatic and cultural relationship between the Goryeo and Song dynasties, Liao-Goryeo relations were exceedingly poor. Both Liao and Goryeo saw each other as posing a military threat; the Khitans feared that Goryeo would attempt to foment rebellions among the Balhae population in Liao territory, while Goryeo feared invasion by the Liao. The Khitans did invade Goryeo in 992, sending a force that the Liao commander claimed to be 800,000 strong, and demanding that Goryeo cede to territories along the Yalu River. Goryeo appealed for assistance from the Song dynasty, with which they had a military alliance, but no Song assistance came. The Khitans made steady southward progress before reaching the Ch'ongch'on River, at which point they called for negotiations between Liao and Goryeo military leaders. While the Liao initially demanded total surrender from Goryeo, and Goryeo initially appeared willing to consider it, the Korean negotiator was eventually able to convince the Khitans to accept a resolution in which the Goryeo dynasty became a tributary state to the Liao dynasty. By 994, regular diplomatic exchanges between Liao and Goryeo began, and the relationship between Goryeo and Song irrevocably chilled. The peace did not last two decades. In 1009 the Goryeo general Gang Jo murdered King Mokjong of Goryeo and put King Hyeonjong of Goryeo on the throne with the intention of serving as the boy's regent. The Liao immediately sent an army of 400,000 men to Goryeo to punish Gang Jo; however, after an initial period of military success and the breakdown of several attempts at peace negotiations, Goryeo and Liao entered a decade of continuous warfare. In 1018 the Khitans faced the most significant military defeat in the dynasty's history when their army was all but annihilated at the Battle of Gwiju by the Goryeo forces under General Gang Gam-chan, but by 1019 they had already assembled another large army to march on Goryeo. At this point both sides realized that they could not defeat each other militarily, so in 1020 King Hyeonjong resumed sending tribute to the Liao, and in 1022 the Liao officially recognized the legitimacy of King Hyeonjong's reign. Goryeo would remain a vassal, and the relationship between Liao and Goryeo would remain peaceful until the end of the Liao dynasty. In 951, the Later Zhou emerged, the last of the five short-lived dynasties making up the Five Dynasties and Ten Kingdoms period. The founding emperor of the Later Zhou died in 954 and was succeeded by his adopted son, who would rule with the name Emperor Shizong of Later Zhou. Shizong believed that the Liao dynasty was poised to invade the Zhou, and in 958 he launched a preemptive military campaign against the Liao, aiming to take the sixteen prefectures ceded to the Liao by Emperor Gaozu of Later Jin in 938. Emperor Shizong died in 959, before his army had even met the Liao forces. In 960 the commander-in-chief of the Later Zhou palace guard, Zhao Kuangyin, usurped the throne, then occupied by Emperor Shizong's seven-year-old son, and proclaimed himself the founder of the Song dynasty. Relations between the Liao and the Song were initially peaceful, with the two dynasties exchanging embassies in 974. Following the collapse of the Tang dynasty, several territories formed small, independent states that were never reunified during the Five Dynasties and Ten Kingdoms period. Additionally, several additional territories that were controlled by military governors during the Tang dynasty had fallen under the control of local warlords following the Tang collapse. Rather than focus on reclaiming land from the Liao dynasty, Zhao Kuangyin, who would take the title Emperor Taizu of Song, focused on reclaiming these smaller break-off territories. He would die in 976 having reestablished control over all but one of these territories, the Northern Han kingdom. Despite the Northern Han's status as a protectorate of the Liao dynasty, Emperor Taizu of Song launched an invasion of the kingdom in 976, only months before his death. The Northern Han received assistance from the Liao, and the invasion was repelled. Emperor Taizong of Song, brother of the founding emperor and the second emperor of the Song dynasty, launched a second invasion in 979. The Northern Han again received Liao assistance, but this invasion was successful; the Northern Han crumbled, and the Song were able to assume control of the territory. Emperor Taizong of Song immediately followed this victory with an attempted invasion of the sixteen prefectures, but the unrested and undersupplied Song troops were thoroughly routed by the Liao in the Battle of Gaoliang River. Over the next two decades, the relationship between the Liao and Song continued to deteriorate. The Liao were continuously informed of Song attempts to create military alliances with other groups sharing a border with the Liao, and minor border skirmishes were common. Beginning in 999 Emperor Shengzong of Liao led a series of campaigns against the Song that, while generally successful on the battlefield, failed to secure anything of value from the Song. This changed in 1004 when Emperor Shengzong led a campaign that rapidly worked its way to right outside of the Song capital of Kaifeng by only conquering cities that quickly folded to the Liao army, while avoiding protracted sieges of the cities that resisted heavily. Emperor Zhenzong of Song marched out and met the Liao at Chanyuan, a small city on the Yellow River. In January 1005 the two dynasties signed the Chanyuan Treaty, which stipulated that the Song would give the Liao 200,000 bolts of silk and 100,000 ounces of silver each year, that the two emperors would address each other as equals, that they would finalize the location of their disputed border, and that the two dynasties would resume cordial relations. While the sums (referred to as gifts by the Song and as tributes by the Liao) were later increased to 300,000 bolts of silk and 200,000 ounces of silver per year out of Song fears that the Liao might form a military alliance with the Western Xia, no major wars were fought between the Liao and Song for over a century following the signing of the treaty. By signing the treaty the Song dynasty functionally ceded its claim over the sixteen prefectures. Emperor Shengzong died in 1031, leaving behind instructions that named his son Yelü Zongzhen as heir. Yelü Zongzhen, known historically by the name Emperor Xingzong of Liao, became the Emperor of the Liao dynasty at the age of fifteen, and his reign immediately became plagued with courtly infighting. Emperor Xingzong's mother was a low-ranking consort, Nuou Jin, but he was raised by Emperor Shengzong's wife, Empress Ji Dian. Nuou Jin quickly moved to marginalize Ji Dian and her supporters, fabricating a coup and using it to justify exiling Ji Dian and executing most of her supporters in several months of purges. Nuou Jin eventually sent assassins to kill Ji Dian; however, Ji Dian instead committed suicide. With her rival for power dead, Nuou Jin declared herself the regent and began personally conducting duties normally within the purview of the emperor. When it became clear that Emperor Xingzong was unhappy with his mother's grab for power, Nuou Jin plotted to replace the emperor with another of her sons, Zhong Yuan, whom Nuou Jin raised herself. Zhong Yuan informed the emperor of their mother's plans, however, and the emperor promptly exiled Nuou Jin. For the remainder of his reign, Emperor Xingzong would have to compete for power with his mother, whose supporters still held key postings, and whose influence was so great that she was eventually allowed to return to the capital and undergo a ceremony to symbolically de-exile herself. Zhong Yuan, for his part, would be rewarded for revealing his mother's plot by being given a succession of higher- and higher-ranking positions, culminating with a governorship outside of the capital. Historian Frederick W. Mote explains the importance of this factional infighting and its relation to the Liao dynasty's downfall by stating that it "shows to what extent the succession issue within the imperial clan still was the source of weakness in the leadership of the state. It wasted people, diverted energies, and deflected the attention of the rulers from the tasks of governing." Emperor Xingzong died in 1055. His eldest son, Yelü Hongji (who would later be known by the name Emperor Daozong of Liao), assumed the throne having already gained experience in governing while his father was alive. Unlike his father, Emperor Daozong did not face a succession crisis. While both Ji Dian and Zhong Yuan remained alive, and both had the political influence to interfere with the succession process, neither did. While Emperor Daozong's reign started off strong, it too was eventually plagued by factional infighting, aggravated by the emperor's own general weakness. The emperor's first major error was in ordering the execution of Xiao A La, a loyal minister and close friend of the emperor, whom the emperor was nonetheless convinced to execute by a rival minister. The 14th-century History of Liao speculates that had Xiao A La not been killed, two major incidents that came to dominate Emperor Daozong's reign would have been avoided. The first of these incidents was a rebellion in 1063, when several high-ranking members of the Yelü clan, led by a grandson of Emperor Shengzong, attempted to assassinate Emperor Daozong while he was on a hunting trip. He was saved with the assistance of troops led by his mother, Empress Dowager Ren Yi, and he retaliated by executing all of the people involved in the plot, as well as their immediate families. This major change in leadership solidified the power of the chancellor Yelü Yixin and his ally Yelü Renxian, a chancellor and military leader. When Yelü Renxian died in 1072, Yelü Yixin began to view Emperor Daozong's son and heir apparent, Prince Jun, as the only possible threat to Yelü Yixin's power, and set in motion plans to eliminate the prince. He first eliminated Prince Jun's mother, the emperor's wife, by fabricating evidence that she had an affair with a palace musician. Believing Yelü Yixin's trap, Emperor Daozong ordered his wife to commit suicide. Yelü Yixin then fabricated a coup by implicating his own enemies within the court of planning to depose of Emperor Daozong and place Prince Jun on the throne. While the emperor was initially unmoved, Yelü Yixin eventually convinced him to exile his son by creating a false confession. Prince Jun was immediately exiled, at which point Yelü Yixin sent assassins to eliminate the prince and his wife, preventing both the prince from being returned to power and Yelü Yixin's plot from being discovered. Yelü Yixin's treachery was eventually discovered when, in 1079, he attempted to convince the emperor to leave the new heir at the palace during a hunting trip. When other members of the court protested that the young boy would be in mortal peril if left behind with Yelü Yixin, the emperor finally saw through Yelü Yixin. By 1080 Yelü Yixin was stripped of his rank and sent to a low-ranking post outside of the capital. Shortly afterwards he was executed. Aside from the machinations of Yelü Yixin, the only other event of note from Emperor Daozong's rule was a war fought between 1092 and 1102 between the Liao and a Mongolian, possibly Tatar tribe, group known as the Zubu. The Zubu were located at the northwest border of Liao territory and had fought several wars with the Liao when the Liao tried to expand in that direction. In 1092 the Liao attacked several other tribes in the northwest, and by 1093 the Zubu attacked the Liao, striking deep into Khitan territory. It took until 1100 for the Liao to capture and kill the Zubu chieftain, and another two years to fight off the remaining Zubu forces. The war against the Zubu was the last successful military campaign waged by the Liao dynasty. The 12th century saw the rapid rise of the Jurchen people, which culminated in 1115 with the foundation of the Jin dynasty by the Jurchen warlord Aguda. The Jurchens, led by Aguda, captured the Liao dynasty's supreme capital in 1120 and its central capital in 1122. The Liao emperor Tianzuo fled the southern capital Nanjing (today's Beijing) to the western region, and his uncle Prince Yelü Chun then formed the short-lived Northern Liao in the southern capital, but died soon afterwards. In 1125, the Jurchens captured Emperor Tianzuo and ended the Liao dynasty. In 1124, just before the final conquest of the Liao dynasty, a group of Khitans led by Yelü Dashi fled northwest to the border area and military garrison of Kedun (Zhenzhou), in modern-day northern Mongolia. Yelü Dashi convinced the people there, around 20,000 Liao cavalry and their families, to follow him and attempt to restore the Liao dynasty. Yelü Dashi proclaimed himself emperor in 1131, after which he moved further west into modern Kazakhstan and then occupied the Karakhanid city of Balasaghun (in modern Kyrgyzstan). After a failed attempt in 1134 to reclaim the territory formerly held by the Liao, Dashi decided instead to stay where he was and establish a permanent Khitan state in Central Asia. The state, known as the Qara Khitai or the Western Liao dynasty, controlled several key trading cities, was multicultural, and showed evidence of religious tolerance. The state survived for nearly a century before being conquered by the Mongol Empire in 1218. An analysis by F. W. Mote concluded that at the time of the Liao dynasty's fall, "the Liao state remained strong, capable of functioning at reasonable levels and possessing greater resources of war than any of its enemies" and that "one cannot find signs of serious economic or fiscal breakdown that might have impoverished or crippled its ability to respond". Mote also concluded that acculturation did not lead to the replacement of traditional Khitan values with Chinese culture, and that the Khitan commoners were "supremely able and willing to fight", which Mote pointed to as evidence that Khitan society remained strong. Mote instead attributes the fall of the Liao to the leadership ability of Aguda and to the actions of the Khitan Yelü and Xiao clans, which used early defeats at the hand of Aguda as a pretext for plotting the overthrow of Emperor Tianzuo. Historian Jacques Gernet disagrees with Mote, writing that "by the middle of the eleventh century the Khitan had lost their combative spirit and adopted a defensive attitude to their neighbors, building walls, ramparts for their towns, and fortified posts." Gernet attributes this change to the influence of Buddhism, which abhors violence, as well as to Chinese wealth and culture in general. Like Mote, Gernet attributes the ultimate downfall of the Liao to the interference by the ruling clans, and he additionally credits a series of droughts and floods, as well as attacks by the Jurchen tribes on the north-east edge of Liao territory, with weakening the Liao to a critical level. At its height, the Liao dynasty controlled what is now Shanxi, Hebei, Liaoning, Jilin, Heilongjiang, and Inner Mongolia provinces in China, as well as northern portions of the Korean peninsula, portions of the Russian Far East, and much of the country of Mongolia. The peak population is estimated at 750,000 Khitans and two to three million ethnic Han Chinese. The Liao employed two separate governments operating in parallel with one another: a Northern Administration in charge of Khitan and other nomadic peoples, most of whom lived in the northern side of Liao territory, and a Southern Administration in charge of the Chinese populace that lived predominantly in the southern side. When Abaoji first established the system, these two governments did not have strict territorial boundaries, but Emperor Shizong established formally delineated boundaries for the two administrations early in his reign. The newly delineated Northern Administration had large Han Chinese, Balhae, and Uighur populations, and was given its own set of parallel northern and southern governments. The governments of the Northern Administration and the Southern Administration operated very differently. The Northern Administration operated under a system which Twitchett and Tietze called "essentially a great tribal leader's personal retinue". Many of the governmental appointments dealt with tribal affairs, herds, and retainers serving the imperial house, and most powerful and high-ranking positions dealt with military affairs. The overwhelming majority of officeholders were Khitans, mainly from the imperial Yelü clan and the Xiao consort clan. The Southern Administration was more heavily structured, with Twitchett and Tietze calling it "designed in imitation of a T'ang model". Unlike the Northern Administration, many of the low- and medium-ranked officials in the Southern Administration were Chinese. The Liao dynasty was further divided into five "circuits", each with a capital city. The general idea for this system was taken from the Balhae, although no captured Balhae cities were made into circuit capitals. The five capital cities were Shangjing (上京), meaning Supreme Capital, which is located in modern-day Inner Mongolia; Nanjing (南京), meaning Southern Capital, which is located near modern-day Beijing; Dongjing (东京), meaning Eastern Capital, which is located near modern-day Liaoning; Zhongjing (中京), meaning Central Capital, which is located in modern-day Hebei province near the Laoha river; and Xijing (西京), meaning Western Capital, which is located near modern-day Datong. Each circuit was headed by a powerful viceroy who had the autonomy to tailor policies to meet the needs of the population within his circuit. Circuits were further subdivided into administrations called fu (府), which were metropolitan areas surrounding capital cities, and outside of metropolitan areas were divided into prefectures called zhou (州), which themselves were divided into counties called xian (县). Despite these administrative systems, important state decisions were still made by the emperor. The emperor met with officials from the Northern and Southern Administrations twice a year, but aside from that the emperor spent much of his time attending to tribal affairs outside of the capital cities. The Khitan spoken language is most closely related to the Mongolic language family; some broader definitions of the Mongolic family include Khitan as a member. More broadly, Khitan is an Altaic language, although scholars are divided on the question whether the Altaic is a true language family or linguistic area in which originally distinct languages have influenced each other over a long period. Khitan shares some terms with the Altaic but non-Mongolic Turkic spoken by the Uighur peoples, who shared the steppes of North Asia with the Khitans for several hundred years. Prior to their conquest of north China and the establishment of the Liao dynasty, the Khitans had no written language. In 920 the first of two Khitan scripts, the Khitan large script, was developed. A second script, the Khitan small script, was developed in 925. Both scripts are based on the same spoken language, and both contain a mix of logographs and phonographs. Despite the similarities to Chinese characters, the Khitan scripts were functionally different from Chinese. Few documents written in either the Khitan large or small script survive to this day. Most surviving specimens of both Khitan scripts are epitaph inscriptions on stone tablets, as well as a number of inscriptions on coins, mirrors and seals. Only a single manuscript text in the Khitan large script is known (Nova N 176), and no manuscripts in the Khitan small script are known. The Liao emperors could read Chinese, and while there were some Chinese works translated into Khitan during the Liao dynasty, the Confucian classics, which served as the core guide to the administration of government in China, are not known to have been translated into Khitan. The status of women in the Liao dynasty varied greatly, with the Khitan Liao (like many other nomadic societies) having a much more egalitarian view towards women than the Han Chinese did. Han Chinese living under the Liao dynasty were not forced to adopt Khitan practices, and while some Han Chinese did, many did not. Unlike Han society, which had a strict separation of responsibilities along gender lines, and placed women in a subservient role to men, the Khitan women of the Liao dynasty performed many of the same functions that the Khitan men did. Khitan women were taught how to hunt, and managed family herds, flocks, finances, and property when their husbands were at war. Upper-class women were able to hold governmental and military posts. The sexual freedoms of Liao also stood in stark contrast from those of the Han Chinese. Women from the upper Liao classes, like those of the Han Chinese upper classes, had arranged marriages, in some cases for political purposes. However women from the lower classes of the Liao did not have arranged marriages, and would attract suitors by singing and dancing in the streets. The songs served as self-advertisements, with the women telling of their beauty, familial status, and domestic skills. Virginity was not a requirement for marriage among the Liao, and many Liao women were sexually promiscuous before marriage, which stood in sharp contrast from the beliefs of the Han Chinese. Khitan women had the right to divorce their husbands and were able to remarry after being divorced. Abduction of marriage-age women was common during the Liao dynasty. Khitans men of all social classes participated in the activity, and the abductees were both Khitan and Han. In some cases, this was a step in the courtship process, where the woman would agree to the abduction and the resulting sexual intercourse, and then the abductor and abductee would return to the woman's home to announce their intention to marry. This process was known as baimen (拜門). In other cases, the abduction would be non-consensual and would result in a rape. In Liao custom betrothal was seen as being equally serious to, if not more serious than, marriage itself, and was difficult to annul. The groom would pledge to work for three years for the bride's family, pay a bride price, and lavish the bride's family with gifts. After the three years, the groom would be allowed to take the bride back to his home, and the bride would usually cut off all ties with her family. Khitan marriage practices differed from those of the Han Chinese in several ways. Men from the elite classes tended to marry women from the generation their senior. While this did not necessarily mean that there would be a large gap in ages between husband and wife, it was often the case. Among the ruling Yelü clan, the average age that boys married was sixteen, while the average age that girls married was between sixteen and twenty-two. Although rare, ages as young as twelve were recorded, for both boys and girls. A special variety of polygamy known as sororate, in which a man would marry two or more women who were sisters, was practiced among the Liao elite. Polygamy was not restricted only to sororate, with some men having three or more wives, only some of whom were sisters. Sororate continued throughout the length of the Liao dynasty, despite laws banning the practice. Over the course of the dynasty, the Liao elite moved away from polygamy and towards the Han Chinese system of having one wife and one or more concubines. This was done largely to smooth over the process of inheritance. By the time Abaoji assumed control over the Khitans in the early tenth century, a majority of the Khitan population had adopted Buddhism. Buddhism was practiced throughout the length of the Liao dynasty. Monasteries were constructed during the reign of the first emperor, Taizu, and Buddhism was especially prominent during the reigns of Emperors Shengzong, Xingzong, and Daozong. Buddhist scholars living during the time of the Liao dynasty predicted that the mofa (末法), an age in which the three treasures of Buddhism would be destroyed, was to begin in the year 1052. Previous dynasties, including the Sui and Tang, were also concerned with the mofa, although their predictions for when the mofa would start were different from the one selected by the Liao. As early as the Sui dynasty, efforts were made to preserve Buddhist teachings by carving them into stone or burying them. These efforts continued into the Liao dynasty, with Emperor Xingzong funding several projects in the years immediately preceding 1052. Evidence from excavated Liao burial sites indicates that animistic or shamanistic practices were fused with Buddhism and other practices in marriage and burial ceremonies. Both animal and human sacrifices have been found in Liao tombs, alongside indications of Buddhist practice. Indications of Daoist, zodiac, and Zoroastrian influences have also been found in Liao burial sites. The influence of the Liao dynasty on subsequent culture includes a large legacy of statuary art works, with important surviving examples in painted wood, metal, and three-color glazed sancai ceramics. The music and songs of the Liao dynasty are also known to have indirectly or directly influenced Mongol, Jurchen, and Chinese musical traditions. The rhythmic and tonal pattern of the ci (词) form of poetry, an important part of Song dynasty poetry, uses a set of poetic meters and is based upon certain definitive musical song tunes. The specific origin of these various original tunes and musical modes is not known, but the influence of Liao dynasty lyrics both directly and indirectly through the music and lyrics of the Jurchen Jin dynasty appears likely. At least one Han Chinese source considered the Liao (and Jurchen) music to be the vigorous and powerful music of horse-mounted warriors, diffused through border warfare. Another influence of the Liao cultural tradition is seen in the Yuan dynasty's zaju (杂剧) theater, its associated orchestration, and the qu (曲) and sanqu (散曲) forms of Classical Chinese poetry. One documented way in which this influence occurred was through the incorporation of Khitan officers and men into the service of the Mongol forces during the first Mongol invasion of 1211 to 1215. This northern route of cultural transmission of the legacy of Liao culture was then returned to China during the Yuan dynasty. The Chinese state news agency Xinhua announced in January 2018 that the ruins in Duolun County, Inner Mongolia, of an ancient palace that served as the summer retreat for the royal family and retinue of the Liao Dynasty. They would move each year from mid-April to mid-July to avoid the heat. The site includes foundations of 12 buildings of more than 2,500 square feet that have been recorded and artifacts, such as glazed tiles, pottery and copper nails that were used to date the site. |Wikimedia Commons has media related to Liao Dynasty.| |Wikimedia Commons has media related to Maps of the Liao Dynasty.| |Dynasties in Chinese history
The increased and widespread use of artificial light at night is adversely affecting our natural environment. Plants and animals depend on Earth’s daily cycle of light and dark rhythm to govern life-sustaining behaviors such as reproduction, nourishment, sleep and protection from predators. Scientific evidence suggests that artificial light at night has negative and deadly effects on many creatures including amphibians, birds, mammals, insects and plants. Artificial light at night disrupts wildlife Many animal species need a natural night sky to navigate Birds: Artificial light causes birds to wander off course, and causes them to miss seasonal clues. Insects: Insects, especially night butterflies, are drawn to light, and lose their ability to forage and propagate. Amphibians: Light pollution alters the nighttime environment. For example, in light- polluted areas, frog singing becomes less pronounced and their propagation gets disturbed. Mammals: Nocturnal mammals, like bats, raccoons and opossums, use the protection of darkness to safely forage and mate. The good news is that light pollution, unlike many other forms of pollution, is easy to reverse and each one of us can make a difference! You can start by minimizing the light from your own home at night. You can do this by following these simple steps. Only use lighting when and where it’s necessary. Choose warm yellow lights rather than cool, bluish lights. If safety is concern, install motion detector lights and timers. Properly shield all outdoor lights, and let the light face downward. Keep your blinds drawn to keep light inside.
Hay fever is a modern common allergic condition, also referred to as allergic rhinitis. Hay fever was first described at the beginning of the Industrial Revolution by Dr John Bostock, who described it in himself. It took him several years to identify a dozen or more hay fever sufferers. This shows that it was quite uncommon before the Industrial Revolution. The incidence of hay fever has steadily increased since the Industrial Revolution and it now affects almost 20% of the population in the UK. The peak age for contracting hay fever is 20 years, although many children suffer, and it may develop at any age. Two of the factors that contribute to hay fever are pollution and weather. Hay fever is twice as common in towns as in the country. This is largely as a result of road traffic pollution and the effect of sunlight on traffic pollution, which is referred to as “photochemical smog”. In 20 years the number of people treated for hay fever has risen over 400% although city pollen counts have dropped. Asthma and eczema are also rising in incidence by about 5% per year. Symptoms of hay fever Hay fever can occur at any time between February and September depending on the pollen(s) responsible. The commonest problem is with grasses and these pollens are produced from April to the end of September. The symptoms of hay fever include: - frequent sneezing - runny or blocked nose - itchy, red or watery eyes - an itchy throat, mouth, nose and ears - cough caused by postnasal drip, which is mucus dripping down the throat from the back of the nose Many suffers have additional symptoms, such as: - the loss sense of smell - facial pain (caused by blocked sinuses) - tiredness, fatigue - sleep deprivation Many people suffer in sunny, bright weather; however, a proportion of people suffer more at the onset of wet, rainy weather. Some people are affected more as a result of the dramatic increase of mould spores which occur during rain and thunder storms. Treatments for hay fever At Breakspear Medical, we use a holistic approach to treatment and avoid drug therapy programmes where possible. Our hay fever treatment varies greatly from traditional treatments, which usually involve the use of antihistamines, steroids and decongestants. Antihistamines often cause drowsiness and many rarely do more than modify the symptoms. Steroids come in many different forms and have many undesirable side effects and reduce immunity to infection. Decongestants are drugs which cause the lining of the nose to shrink, thus reducing the congestion which occurs as a result of histamine release in hay fever. Unfortunately decongestants often need to be taken with increasing frequency, in increasing dosage, and symptoms may become even worse as the drug’s effects wear off. The first step in treating your hay fever is to have a consultation with one of our doctors. After this, your doctor will put together your treatment programme. We specialise in the treatment of allergy, intolerance and sensitivity by using the proven system of allergy management called low-dose immunotherapy (LDI), together with a nutritional supplement programme, which supports your immune system. Hay fever sufferers undergoing treatment will receive: - a booklet with information and tips on how to change your environment and diet to improve your condition and a listing of the allergens for which you will be tested including such items as histamine, various moulds and pollens - a nutritional supplement programme to strengthen your immune system. Good nutrition is important because some foods can exacerbate symptoms; some people are helped by avoiding wheat and histamine-containing and histamine-releasing foods, such as cheese, strawberries, pork and shellfish. Breakspear Medical treats each patient individually, which means that there is no standard treatment programme for everyone with hay fever for a set price. After your first appointment, you will be given a detailed estimate, with your recommended treatment programme with all the costs, which will be explained to you by your Patient Liaison Officer. On the day of your appointment or anytime afterward, if you have any specific questions regarding prices, estimates and treatment programmes, please contact a Patient Liaison Officer, by phone 01442 261 333 ext 604, or email: [email protected]
Looking for some fun, nature-based activities for home? Our environmental education staff have put together some resources for activities you can do at home, in your backyard, or during a walk in your neighbourhood. - Bugs Scavenger Hunt – learn more about the insects you can find around you - Nature Alphabet Scavenger Hunt – can you find items in nature from A to Z? - Weather Wise – learn how weather conditions affect the things around you - Soil Study – learn more about the soil in your area - Food Chain Challenge – complete the food chain for each habitat! - Spring Phenology – the study of changes in plants and animals as they respond to weather, climate, and the seasons. What can you observe around you? - Rock Exercises – want to become a “Rock hound”? Learn about the rocks in your area. - Weird Creature Features – are these weird facts true or false? Colouring & Activity Sheets - Birds – The Hamilton area is home to many exciting bird species! - Did You Know? – some interesting nature facts - Dragonflies and Damselflies - Draw a self-portrait of yourself in nature and the creatures you meet - Exploring Journal – take some time to be with nature - Falling Tree Leaves – how many leaves can you identify? - Fish Species – what do you know about fish? - Frogs – from eggs to tadpoles to frog! - Healthy Habitats – learn more about natural habitats in Hamilton - Helping the Environment – what can you do at home? - Importance of Plants – Plants have many uses which make them important! - Leaf Discoveries – what type of leaves can you see around you? - Match the Tracks – can you identify the footprints? - Native Plants Word Search - Red Fox Maze – help the Red Fox get back to his forest home! - Species at Risk Connect the Dots – learn more about Jeffy the Jefferson Salamander - Spot the Difference – conservation area do’s and don’ts - Spring at Valens Lake colouring page - Things that Creep, Crawl, Hop & Fly - Turkey Vulture colouring page - Water Cycle – learn how water moves through Earth’s land, waterways, and atmosphere - Word Scramble – Unscramble the words to find some of the snakes and turtles that are native to the Hamilton area
According to wave mechanics, the atomic orbitals can be expressed by wave functions (ψ ’s) which represent the amplitude of the electron waves. These are obtained from the solution of Schrödinger wave equation. However, since it cannot be solved for any system containing more than one electron, molecular orbitals which are one electron wave functions for molecules are difficult to obtain directly from the solution of Schrödinger wave equation. To overcome this problem, an approximate method known as linear combination of atomic orbitals (LCAO) has been adopted. Let us apply this method to the homonuclear diatomic hydrogen molecule. Consider the hydrogen molecule consisting of two atoms A and B. Each hydrogen atom in the ground state has one electron in 1s orbital. The atomic orbitals of these atoms may be represented by the wave functions ψA and ψB. Mathematically, the formation of molecular orbitals may be described by the linear combination of atomic orbitals that can take place by addition and by subtraction of wave functions of individual atomic orbitals as shown below. The molecular orbital σ formed by the addition of atomic orbitals is called the bonding molecular orbital while the molecular orbital σ* formed by the subtraction of atomic orbital is called antibonding molecular orbital as depicted in Fig. Qualitatively, the formation of molecular orbitals can be understood in terms of the constructive or destructive interference of the electron waves of the combining atoms. In the formation of bonding molecular orbital, the two electron waves of the bonding atoms reinforce each other due to constructive interference while in the formation of antibonding molecular orbital, the electron waves cancel each other due to destructive interference. As a result, the electron density in a bonding molecular orbital is located between the nuclei of the bonded atoms because of which the repulsion between the nuclei is very less while in case of an antibonding molecular orbital, most of the electron density is located away from the space between the nuclei. Infact, there is a nodal plane (on which the electron density is zero) between the nuclei and hence the repulsion between the nuclei is high. Electrons placed in a bonding molecular orbital tend to hold the nuclei together and stabilise a molecule. Therefore, a bonding molecular orbital always possesses lower energy than either of the atomic orbitals that have combined to form it. In contrast, the electrons placed in the antibonding molecular orbital destabilise the molecule. This is because the mutual repulsion of the electrons in this orbital is more than the attraction between the electrons and the nuclei, which causes a net increase in energy. It may be noted that the energy of the antibonding orbital is raised above the energy of the parent atomic orbitals that have combined and the energy of the bonding orbital has been lowered than the parent orbitals. The total energy of two molecular orbitals, however, remains the same as that of two original atomic orbitals.
Antimicrobial resistance (AMR) is threatening populations around the world, simply because bacteria are evolving at such a rate that they essentially become unaffected by the medications meant to kill them. It's estimated that about 700 000 people die annually from drug-resistant strains of illnesses, such as bacterial infections, tuberculosis and malaria. Economist Jim O'Neill conducted a review of AMR, and experts warned that if nothing is done about the problem, 10 million people around the world will die by 2050. The World Health Organization (WHO) has developed a global action plan to take on AMR. They have increased awareness around the problem and are encouraging healthcare professionals to take extra care with antimicrobial medication, and not to prescribe medication unnecessarily. AMR can happen in two ways: - When medication doesn't kill all bacteria in infected people, it allows the bacteria to grow and evolve, resulting in resistance. - When people are infected with a strain which has already grown and evolved to resist antimicrobial drugs. In cases where bacteria grow and evolve, antimicrobial medication kills off sensitive bacteria, but doesn't kill off all bacteria. This results in the bacteria mutating and multiplying to replace the sensitive bacteria, which the medication initially killed off. During a summit held earlier this year, the South African Medical Research Council (SAMRC) and the Foundation for Innovating New Diagnostics (FIND) presented their findings around AMR and how health systems that are under strain require urgent intervention. Delegates at the meeting also said that these health systems need innovations which are sustainable, affordable and can be taken to scale.
Text-to-speech or TTS may have established its presence in the technology market as one of the most innovative platforms dedicated for assistive purposes.TTS is more and more being used in the education sector in which the technology is primarily utilized to assist the physically challenged with their learning. One example of a company dedicating its work to developing assistive learning tools for students with difficulties and disabilities is Spectronics. In an article published by the company on its website, Spectronics stated its mission to aid the learning institutions particularly educators in bridging the learning gap for the disabled learners. In addition, the company believes that: Classroom teachers support students with diverse abilities and needs, cultural backgrounds, experiences and learning styles. As teachers, we are required to make use of strategies and resources that engage, motivate and encourage active participation and learning by all students. The authors, proposes that inclusive technologies being used for assistive learning should be highly integrated into the educational institution’s core learning concepts to accommodate the needs of students with disabilities and various difficulties. Furthermore, the authors pointed out that, “Students with learning difficulties can be defined as students who experience particular difficulties in achieving at school that are not due to a disability or impairment. (Ashman, 2005; Westwood, 2003) Students with learning disabilities include those students with chronic academic problems. These students may have been diagnosed with dyslexia, dyspraxia, dyscalcula, disgraphia or other neurologically based conditions”. In this sense, the learning community recognizes the need for TTS-enabled learning tools such as OCR (optical character recognition), Talking Books, Softwares that convert text into audio, and writing tools such as onscreen word banks and portable note-takers. One of the reasons that writing should be also considered a fundamental part of the TTS-enabled technologies is that, “Common problems for students with learning difficulties and disabilities center around spelling, grammatical errors, tense and punctuation. They may have ideas, which they can articulate very well, but because of spelling problems fall back on using simple sentence construction and vocabulary. These students often need scaffolding to help organize and articulate their ideas into a written format” (Smith et al, 2017). Inclusive technologies may be designed to remediate specific difficulties and contain key supportive features, while others have many features that support a range of learning needs. They may be standalone programs or may integrate with other commonly used applications. On the other hand, many of the technologies outlined in this article will not eliminate or fix learning difficulties. There is evidence, however, that such technologies can compensate the students’ disabilities and difficulties as well as assist students to develop skills to improve their literacy. They definitely allow teachers to encourage students to capitalize on their strengths and work towards independence and self-reliance.
Once the body does not have adequate water and fluids to perform normal bodily functions, the outcome can be serious. The loss of fluids and insufficient replenishment leads to dehydration. Certain illnesses and engaging in highly strenuous activities can cause dehydration. When engaging in strenuous activities, especially during warm weather, it is vital to rehydrate the body since a lot of fluids were lost during the activity. There are some initial indications of dehydration that suggest the necessity for increased fluid intake in order to prevent any complications. Some of these symptoms are clearly linked to dehydration while others might be associated to other health conditions. It is important to note that dehydration can be triggered by various factors which include fever, diarrhea, excessive sweating, vomiting and prolonged exposure to heat. If the individual experiences mild thirst, it can indicate dehydration. Always bear in mind that this sensation is the natural response of the body in an attempt to prevent any serious complications linked with insufficient fluid levels. A case of severe dehydration can lead to thirst that could not be quenched. The recommended fluids include clear and beverages free from sugar. Avoid carbonated beverages, caffeine and sugar-based drinks until the condition has improved. Dryness of the mouth is often an early indication of dehydration. The mouth and tongue might feel tacky or gluey. In most cases, bad breath is due to the mouth dryness and can be considered as another early sign of dehydration. Once the fluid levels in the body are reduced, the urinary output can be affected. Some individuals might initially notice urine that is darker in color than usual with a pungent odor. In the long run, dehydration can progress to a reduced amount of urine. Among infants and young children, this can indicate very few wet diapers. Dry mucous membranes The body will attempt to conserve any fluids that do not exist. It simply means withholding any unwanted secretions such as tears. When infants or children are dehydrated, they will no longer have any tears. In some cases, even the nose will dry out as well as chapped and dry lips. An individual who is dehydrated can experience headaches or muscle weakness. Depending on the severity of dehydration, these can range from mild to moderate. Restoring the level of hydration in the body can help improve these symptoms, especially with the help of sodium-containing beverages such as clear broths. Lightheadedness or dizziness can also develop. In addition, lack reduced fluids in the body can lead to sleepiness or unusual tiredness, especially among children. Once any of the early indications of dehydration are present, it is vital to perform the necessary measures to alleviate the symptoms. If the symptoms are ignored and eventually progress, dehydration can be life-threatening and would require immediate medical attention.
An important part of the day is the exploring of the world through the senses and movement. Our Curriculum and center time is a time to explore the sensory tables, table toys, dramatic play areas, and art materials. Children learn how to learn, experiment with art materials, and increase their muscle control during this play. They learn about communicating and working with other children and adults. During group time, children hear stories reflecting the theme of the month, counting, alphabet, or Bible teachings. They sing and do movement activities to reinforce learning and develop motor skills. Teachers provide science and math activities during this time. In science, they are learning about cause and effect, asking the question “If we ______, what will happen?”. Math includes counting, size and shape identification, and sorting. A combination of child choice and teacher directed activities provides an optimal environment for children to explore and teachers to encourage specific learning. In the classroom, twos are encouraged to use their emerging skills of dressing themselves, toileting, feeding themselves, calming themselves for rest time, and choosing centers and materials. These experiences and successful achievements help develop their self confidence and independence. Combined with encouragement of the self-help skills, our teachers promote the socials skills of listening in a group, communicating needs and wants, conversational skills, taking turns, and problem solving. Two year olds are excited by life and all it has to offer. In the classroom, children are encouraged to learn self-help skills, fostering independence. An important part of their day is exploring their world through the five senses and movement. A combination of child choice and teacher directed activities provides an optimal environment for children to explore and teachers to encourage specific learning.
Taking It Home When one tugs on a single thing in nature, he finds it attached to the rest of the world. — John Muir IN TODAY'S SESSION... The children heard a true story about unexpected consequences after scientists sprayed DDT in Borneo to get rid of mosquitoes. A chain of subsequent events led to an overpopulation of rats, which was solved by parachuting 20 cats into Borneo. We talked about the importance of balance in nature and made "Live in Balance" posters. EXPLORE THE TOPIC TOGETHER. TALK ABOUT... Ask your child to tell you about the story and what happened. Talk about the ecosystem your city, town or country location is part of. Discuss the wildlife and plants in your area and the interconnections that exist. EXTEND THE TOPIC TOGETHER. TRY... A FAMILY RITUAL Create a family ritual of going for a night hike whenever there is a full moon. Walk quietly and listen for the night sounds. Note the differences in plant and animal life based on the seasons. When you have returned home, have each person light a candle and name something they appreciate about nature or something they noticed or learned on the hike. Close the ritual with lemonade in the summer, hot chocolate in the winter, mulled apple cider in the fall or another seasonal treat. A FAMILY GAME Create an ecological balance version of the traditional game "rock, paper, scissors." In this game, each person secretly decides to be "rock," "paper" or "scissors." Participants count to three with one hand behind their backs. On "three," they pull their hands out front and use their hands to indicate which things they've chosen. A rock is shown by making a fist, paper is a flat hand, and scissors are made in a cutting motion using the index and middle fingers. Rock crushes scissors, scissors cut paper, and paper covers rock. Make up your own version using natural food chain relationships. For example: frogs eat mosquitoes, mosquitoes bite humans, and humans eat frogs. Make up hand gestures for each creature you include. Be creative and don't feel constrained by the number three. If you like, add multiple plants or creatures to your game and think about the ways they are interdependent. Study the problem of global warming with your family. Your library and the internet will have multiple resources. You can also check out the website of Unitarian Universalist Ministry for Earth , an affiliate organization of the Unitarian Universalist Association. Ask a local energy company to do an audit of your home's energy usage and create a plan for more efficient energy use. Create a family plan to reduce your family's carbon emissions and help stop global warming. You may like to find out about local nature or ecological organizations in your area. These may have visitor centers, family programs or volunteer opportunities for young school-age children. Visit a local conservation area and talk to rangers or other workers about local conservation needs. Learn about ways you can help keep the balance in your ecosystem. Possibilities might include planting bushes or flowers that are helpful to insects or birds, reducing your household waste and increasing your recycling efforts, or volunteering with a local environmental group. For more information contact [email protected].
American colonists sought religious freedom in their new home. The unanticipated byproduct of this search was an atmosphere of religious diversity. According to Patricia Bonomi, professor emeritus at New York University, many early colonists realized that if they wanted to freely practice their beliefs, they needed to allow their neighbors that same freedom. Degrees of religious tolerance varied by region, however. The Massachusetts Bay Colony tried to enforce Puritanism on all its settlers, and the American South predominantly adhered to the Church of England, although there were enclaves of minorities present even in those two locations. One notable example was Roger Williams’ community of religious tolerance in Rhode Island. The Middle Colonies, which were New York, New Jersey, Pennsylvania, and Delaware, largely encouraged pluralism. A 1771 woodblock of the New York skyline reveals an interesting phenomenon: there was no dominant majority denomination. Out of 18 churches present, there were three Dutch Reformed churches, three Anglican, three Presbyterian, two Lutheran, one French Huguenot, one Congregational, one Methodist, one Baptist, one Quaker, one Moravian, and one Jewish. In 1657, a New York governor attempted to prohibit the Quaker religion and was delivered the Flushing Remonstrance of 1657, a document often considered to be the forerunner to the First Amendment. Thirty-one men, none of whom were Quakers, protested the governor’s measures. Along with numerous denominations, fringe communes were also present in colonial America. One such group was the Woman in the Wilderness commune, located outside Philadelphia. They combined pagan, Christian, and Jewish traditions in their own nature religion. Not only were the colonists religiously diverse, but Native American and African faiths added another layer of complexity. Native Americans generally honored and respected the religious differences amongst tribes, and many of their religions contained common elements. African slaves often blended traditional spirituality with Christian elements. In fact, Pennsylvania’s Germantown Quaker Meeting group issued America’s first antislavery proclamation in 1688. Near the end of the eighteenth century, the Founding Fathers formally recognized religious diversity in the First Amendment. This article created an environment in which each religion had a voice and the ability to practice freely. William Penn’s “Holy Experiment” is one of the most intriguing examples of religious plurality in colonial history. Penn was an English Quaker who sought to create a haven of religious tolerance, and attracted other Quakers, Lutherans, Moravians, Mennonites, and Amish, among others. His community wasn’t perfect; it excluded atheists, and Jews and non-Christians could not vote. However, the community promoted fair treatment for Native Americans and did not maintain a military. Penn wrote a charter that included education for boys and girls, an enlightened penal code, work for everyone, and freedom of religion. Even in a nation that is 78 percent Christian, there’s plenty of diversity present, and ample opportunity to create modern holy experiments in our own communities. Accepting our religious differences is simply a starting point. When we realize that we have something to learn from those of different faith backgrounds, true growth can thrive. Image courtesy of the Pennsylvania Academy of Fine Arts, Philadelphia.
Using reps and max of weightlifting, students will create a frequency table and compute the mean, median and mode. Teacher will read aloud "The Greedy Triangle" by Marilyn Burns. After read aloud the class will create a list of the geometric shapes from the story. Students will add geometric shapes to the list that were not included in the book (e.g., three dimensional objects). Then students will work with a partner to walk around the school campus to find real-life examples of their assigned geometric shape and take digital photographs of the objects. Students will create a class book about the objects and use their digital photographs to illustrate the book. In this lesson, the student will learn to compare and contrast between different coins. Using hands-on examples, a document camera to review as a class and presentation software (PowerPoint or Keynote) or video editing software (iMovie or Movie Maker). This is a review lesson after the students have already learned about representing fractions. The student will find the fraction of colors in a bite size bag of skittles. They will then predict and discover what color there is the most of in the whole class.
During the first week or so of the school year, I take time to review some basic concepts from previous years with my Grade 9 students – in particular, integer operations, fractions, and fraction operations. The challenge is designing tasks that embed review and practice within problems or activities that also call for generalization, problem solving, or engagement with novel or less-familiar mathematical ideas. I deem this necessary because, of course, not all students come to high school with the same understandings and strengths, and while some do need the opportunity to review basic concepts, others are ready to move on. For the latter group, review activities are at a high risk of being perceived as baby-ish and not worth the time, which means that I need to design these tasks very carefully – that is, in such a way that I can simultaneously assess the needs of students who are still struggling with basic concepts and challenge students who are ready to learn something new. I’d like to share one task that, I think, had something to offer to all of my students: Integer Bingo, which is based on a task developed by and discussed in Serradó (2016). I chose this task for several reasons: - It gives students an opportunity to review integer operations, and me an opportunity to assess their understanding and note any misconceptions in this area. - The review is embedded within a task that challenges students to wrestle with the less-familiar concepts of randomness, relative frequency, theoretical probability, and elementary outcomes. - It’s easily adaptable (to suit a variety of grade levels and to target a variety of concepts) and extendible. Not only does it offer practice with a targeted concept, it can serve as a launch into the study of probability. - Who doesn’t like bingo? Here’s how the task was enacted in my class. Preparation: In preparation for the task, I marked two sets (one yellow and one white) of nine ping-pong balls with the integers from -4 to +4 and placed each set into a paper bag. (A random number generator such as this one can also be used, but I elected to use physical random generators for a particular reason, which I’ll discuss below). I also generated a 4×4 bingo card for each student in my class using Excel, with each cell containing a number that is the sum of two random integers between -4 and +4. Numbers may be repeated. (Click here to download a set of 38 unique cards.) Game play – Round 1: Unlike in most bingo games, where the goal is to get a line, students’ goal in Integer Bingo is to get a “blackout” (to mark off all of the numbers on their card). During the game, I repeatedly draw, with replacement, a number from each bag. If the sum of those numbers is on a student’s card, they can cross it off; if it appears more than once, they cross it off only once per draw. Draw, add, repeat, until someone crosses off all of the numbers on their card and calls “bingo!” The review, obviously, is in determining the sums (another skill can easily be targeted by changing the operation, or changing the numbers – of course, this changes the possibilities for numbers on the cards). At several points during the first round, I asked students to explain how they reasoned through the computation. The numbers are small, but the task still allowed misconceptions to surface – e.g., “Two negatives make a positive, right?” Important conversations to have at the start of the year. Design: After the first round and the first “bingo!,” which took somewhere between 5 and 10 minutes (next time, I’d like to time it for comparison), I presented students with the following challenge: “In your groups, design a card that you think will be most likely to win. You must be able to justify your choices of numbers.” I handed out blank cards, whiteboards, and markers. Circulating, I noticed that some groups filled out their cards in a matter of several minutes or less. Here’s an example of one of these: When I asked them about their choices, many students stated that “these were the numbers that came up most often” – in other words, their arguments were based purely on the observed frequencies, rather than on an underlying theoretical probability distribution. This might explain why, for example, -1 appears more often on the above card than 0 and 1. Other students seemed to be looking beyond the observed frequencies to the underlying distribution, referring to “more possibilities” or “more ways to get” certain numbers, but couldn’t clearly articulate their reasoning beyond this when prodded. I brought the class together again to discuss these issues. Through the conversation, we were able to establish that one way to reason about more likely outcomes is to list all of the ways that the integers -8 to 8 can be produced as a sum of integers between -4 and 4. This discussion served as a theoretical foothold, allowing students to articulate their intuitions through the mathematical process of determining possibilities. I offered students time to explore these possibilities, probing and challenging their thinking as I interacted with the groups. Because many of the groups had already hastily filled in the card I handed out at the outset of the construction phase, I eventually handed out a second card for them to fill out using what they had discovered. (Next time, I will hand out the blank cards near the end of this phase.) Game play – Round 2: Once all of the groups had finalized their cards, we played the game again. I allowed student groups to play with both of their cards (mainly because I was worried about time; otherwise, I would have asked them to choose the one they thought would be more likely to win). As most groups had filled their cards with 0, ±1, ±2, and ±3, there were audible groans around the room when sums such as 8 and -7 came up – sometimes, several times in a row. Again, we played until a group crossed off all of the numbers on their card. This round was noticeably shorter than the first (but I would like to time both rounds next time to compare). Discussion: During the post-game discussion, I asked students to explain why, if 0 and ±1 were so likely and ±7 and ±8 were so rare, we still observed them several times during the drawing process, which led us to discussing the distinction between possibility and probability: “It’s rare, but it can still happen.” We also grappled with the question of whether -7 and -8 were equally likely outcomes, which hinged on the question of whether (-3,-4) was the same outcome as (-4,-3) (a question I had posed to several of the groups during the design phase, which sparked some debates among the students). “Yes, because it’s the same sum,” argued several students; “no, because you can get it in two ways,” argued others. Having physical random generators was helpful during this particular discussion, because the drawing process was transparent. As one student eventually explained, “to get -7, you can either draw a yellow -3 or -4 from the first bag, and then you need to draw a white -4 or a -3 from the second bag. But to get -8, you need a -4 from both bags. So -7 is more likely.” Shortly after this point, the class drew to a close. Next week, as we continue our review, I am going to extend this task by having students design cards most likely to win if the numbers drawn are multiplied. Since students will be familiar with game play, and because I would like them to consider not only the probabilities, but also the possibilities themselves, we won’t start with a practice round. To reiterate, this task fulfilled my criteria for a back-to-school review activity, but also has other bonus features that made it stand out to me as a Good Task: - It gave me an excuse to briefly delve into the topic of probability with my students, which is unfortunately not part of the Math A90 curriculum. Those who are lucky enough to be teaching probability may find this to be a fruitful space to explore several important concepts related to the topic; I could see this task being stretched over several days, as I suggest below. - It gave my students an opportunity to review a basic concept (integer operations), and gave me an opportunity to assess their understanding and note any misconceptions in this area. - The review was embedded within a task that challenged students to wrestle with less-familiar concepts (in this case, randomness, relative frequency, theoretical probability, and elementary outcomes). As a result, it was appropriate and engaging for most students in the room – and additionally so, because there were stakes attached to designing a card well: namely, winning the game. (Although I’m not into bribing students into learning, I will note that when suckers are on the line, students tend to pay attention.) - It’s readily adaptable and extendible. Next week, we will consider possibilities when integers between -4 and 4 are multiplied; the task can be made even more interesting when the operation is randomized as well (e.g., use a die with multiplication, addition, and subtraction symbols). Imposing the winning arrangement to be a line, an X, or an L (for example) adds yet another layer to the task. If, on the other hand, your students are just starting to explore the concept of probability, you might wish to (as in Serradó, 2016) introduce another round between the introductory round and the construction phase, where students must choose between two pre-made bingo cards, play the game with their selection, and reflect on the outcome before designing their own card. In this context, I think the task could be easily stretched over several days, with several iterations of choose-play-reflect and/or construct-play-reflect that give students opportunities to develop increasingly sophisticated reasoning about randomness, uncertainty, and probability. If you have other ideas for how this task can be adapted or extended, I’d love to hear them. I’m looking forward to trying out different variations with my students as we warm up for the new school year. Serradó, A. (2016). Enhancing reasoning on risk management through a decision-making process on a game of chance task. Paper presented at the 13th International Congress on Mathematics Education, Hamburg, Germany, July 2016. Available at https://iase-web.org/documents/papers/icme13/ICME13_S13_Serrado.pdf
What proud parents we are when we see our children excel in school! Without a doubt, yes, we are very proud! But do we know what our children are extraordinary at, other than their academic curricula? That is where we, as parents, need to excel. It’s imperative for us to find out what talents our children already possess or what is that they find interesting. Children start showing their likes and dislikes from a very young age. We need to figure out what their interests are and if there’s any hobby they wish to pursue. Children need to be shown the possible hobbies in which they can engage themselves. Studies have shown that children who have hobbies can actually perform better in academics. Hobbies teach children important life lessons, such as teamwork, confident social interactions, and enhanced self-esteem. The extra-curricular activities help a child develop mentally, physically and emotionally. And that is why we need to encourage our children to develop or pursue hobbies of their liking. Have you noticed your child dancing to that hip song that just got released, or maybe singing to its tune? Ever seen them collecting different kinds of insects or butterflies? Those can be considered as signs of hobbies children could pursue. Read onwards to know how you can encourage your child to take on something that they like. - Observe the child’s interests and give them options as to what they can pursue: When you look at them engaged in playing games with other kids, observe that they might like playing treasure hunt, collecting discarded items and creating something out of that rubble, trying to play that guitar that you bought them last Christmas, or collecting currencies of different countries whenever or wherever they find them. Don’t sweat it if you don’t see them showing interest in anything yet. Try giving them options that you already know about. Ask them if that’s something they’d like to try. For example, cooking, designing buildings using Lego or drawing them up, hiking, reading, painting, skateboarding, etc. - Put them into action: Try to match their liking to their interest levels. For example, if your child is into gourmet TV channels, then probably ask them if they can help you in the kitchen, maybe kneading a dough or boiling spaghetti, or ask them if they’d like to know the entire process of making meatballs. Involve them in the activities that they enjoy doing, starting with baby steps. - Provide them with required room and tools: Once you have had a rough idea of what they like, provide them with space and the necessary equipment related to their hobbies. Every hobby requires some kind of investment to start with. But that doesn’t mean you have to make a huge investment; start off small and basic. - At first get involved with them in their trial period and talk about how they can manage their hobbies: When kids are young and they are still figuring out if they like something, be with them and their progress with the hobby they’re pursuing. Encourage them to keep trying more and give it 100% before deciding whether it is for them or not. When they’re a bit older they will be able to understand how to manage their hobbies themselves. - Find opportunities through different sources for the hobbies that they like: You can look out for opportunities, like at the start of a new school year when various clubs and organizations start up their activities, or when summer camps are hosted. - Assign time for hobbies: There are certain hobbies which do not need to be assigned a time, like cooking, crafting or painting, but some of them, like hiking, trekking, cycling or gardening, need to be planned beforehand. So decide on a time for the hobbies so that your child is able to find time to pursue them. - Be supportive of their hobby even it seems out of the ordinary to you: Your child might be interested in something that you don’t understand. In such a case, do not discourage them. Talk to them about it, so you both are on the same page and you understand their intentions without being judgemental. - Be very careful to not get carried away in pushing your children into hobbies that are your interests: In the pursuit of finding your child’s hobby, you might stumble upon something you like immensely and unknowingly push your child to follow the same. Be cautious not to do that. However, you can model certain behavior to see if your child might want to do what you’re doing. For example, if you want to communicate that you read for fun, model it to show them that; if they like the idea, they’ll follow. - Always respect their changing interests: It is too early for a child to decide what they enjoy doing the most. There may be phases; they start out with painting as a hobby, then might move to studying astronomy. This shift in interest needs to be acknowledged and respected. Only by trying out different hobbies does one get to know which they enjoy the most. - Never undermine even their smallest of achievements: There is a possibility that you might not think Mine Craft is the greatest of games, but if your child enjoys it, then you shouldn’t undermine them. This will put them off from revealing anything to you in the future course of time. Dan M. is a healthcare professional and likes to share knowledge related to fitness, wellness, parenting, and natural health.
5.3.1 Outline how population size is affected by natality, immigration, mortality and emigration. Natality: increases population size as offspring are added to the population. Immigration: increases population size as individuals have moved into the area from somewhere else and so this adds to the population. Mortality: decreases the population as some individuals get eaten, die of old age or get sick. Emigration: decreases the population as individuals have moved out of the area to go live somewhere else. 5.3.2 Draw and label a graph showing a sigmoid (S-shaped) population growth curve. Figure 5.3.1 - A sigmoid population growth cruve 5.3.3 Explain the reasons for the exponential growth phase, the plateau phase and the transitional phase between these two phases. The sigmoid graph showing the population growth of a species has three phases which are; the exponential phase, the transitional phase and the plateau phase. At the start of the sigmoid curve we can see the exponential phase. This is where there is a rapid increase in population growth as natality rate exceeds mortality rate. The reason for this is because there are abundant resources available such as food for all members of the population and diseases as well as predators are rare. As time passes, the population reaches the transitional phase. This is where the natality rate starts to fall and/or the mortality rate starts to rise. It is the result of a decrease in the abundance of resources, and an increase in the number of predators and diseases. However, even though population growth has decreased compared to the exponential phase, it is still increasing as natality rate still exceeds mortality rate. Finally, the population reaches the plateau phase. Here, the population size is constant so no more growth is occurring. This is the result of natality rate being equal to mortality rate and is caused by resources becoming scarce as well as an increase in predators, diseases and parasites. These are the limiting factors to the population growth. If natality rate starts to drop then mortality rate will drop too as more resources become available. As natality rate starts to increase again so does mortality rate as resources become scarce. This keeps the population number relatively stable. If a population is limited by a shortage of resources then we say that it has reached the carrying capacity of the environment. - Rapid increase in population growth. - Natality rate exceeds mortality rate. - Abundant resources available. (food, water, shelter) - Diseases and predators are rare. - Natality rate starts to fall and/or mortality rate starts to rise. - There is a decrease in the number of resources. - An increase in the number of predators and diseases. - Population still increasing but at a slower rate. - No more population growth, population size is constant. - Natality rate is equal to mortality rate. - The population has reached the carrying capacity of the environment. - The limited resources and the common predators and diseases keep the population numbers constant. 5.3.4 List three factors that set limits to population increase. - Shortage of resources (e.g. food) - Increase in predators - Increase in diseases and parasites
Monster Seminar JAM - Acid Rain: An Unfinished Environmental Problem Dr. Gene E. Likens, Institute of Ecosystem Studies Acid rain is a serious environmental problem affecting large regions of the Earth. Large areas of North America, Europe and Asia, as well as parts of the Southern Hemisphere, receive wet deposition that is 10 to more than 30 times more acid than would be expected from an unpolluted atmosphere. Acid rain was first observed in North America at the Hubbard Brook Experimental Forest in the White Mountains of New Hampshire (Likens et al. 1972). Studies of precipitation and streamwater chemistry have been done there since 1963, comprising the longest, continuous record of this type in the world. Federal legislation in the United States, the1990 Clean Air Act Amendments, directly addressed the acid rain problem in the U.S. for the first time. Large amounts of calcium, an important plant nutrient, and other base cations have been depleted from forest ecosystems in the northeastern United States during the past 50 years by acid rain. As a result of the depletion of calcium, ecosystems within the Hubbard Brook Experimental Forest are much more sensitive to continuing inputs of strong acids in atmospheric deposition than expected based on long-term patterns of sulfur biogeochemistry alone. Depletion of calcium from the ecosystem has long-term implications for forest growth, as well as for changes in stream ecosystems and downstream lakes within the landscape. A watershed-ecosystem experiment was initiated in 1999 in the Hubbard Brook Experimental Forest to test the role of added CaSiO3 to a calcium-depauperated landscape. University of Washington Date and Time: October 5, 2006, 11:00 am - 12:30 pm
In this session, you will learn to do the following: • use geometric thinking to solve visualization problems • use mathematical language to express your ideas and to understand the ideas of others. There are many learning games online that kids of all ages can play not only are they effective in teaching kids new things, these learning games are. Learn how to master the most important fundamentals of math. Learning math can be tough belongingness provides a basis for persevering through the difficulties associated with solving problems when students feel connected in the classroom, the difficulty that is a necessary component to understanding math will feel less like a personal threat and more like a natural part of learning. How can the answer be improved. How to learn math is a free self-paced class for learners of all levels of mathematics it combines really important information on the brain and learning with new evidence on the best ways to approach and learn math effectively many people have had negative experiences with math, and end up disliking math or failing. Practice your math facts with fun interactive games check addition subtraction multiplication and division math facts games. To begin the course, we first discuss why the study of geometry can be beneficial, both in school and work as well as in daily life 16 total points lesson 1 video a. Log in page for compasslearning customers to view the compasslearning corporate website, please visit compasslearningcom. Learning resources offers a variety of educational, geometric toys and games to stimulate their thinking and kick start their learning of geometry. We love to celebrate our top mathletes on the mathletics hall of fame see the full list of names, schools and countries online at mathleticscom now. Funbrain is the leader in online educational interactive content, with hundreds of free games, books & videos for kids of all ages check out funbrain here. Desmos is proud to announce the release of our geometry toolwant to learn how to use the tool you're in the right spot watch the introductory video on the right, then dive deeper with the resources below. Visual learners (and kinesthetic learners) learn basic math facts much easier when they can represent them with 3d manipulatives blocks, cubes, legos , play money (or real money), and dice can all be invaluable tools for helping the visual learner to “see” how all the math facts work together. Learn mathematics while you play with it interactive math lessons that help to improve your math. All the advice given for this question is great however, i would like to add one thing if you really want to (re)learn high school mathematics, i would suggest ( first ) pick up books on mathematical and logical puzzles. World's largest library of math & science simulations gizmos are interactive math and science simulations for grades 3-12 over 400 gizmos aligned to the latest standards help educators bring powerful new learning experiences to the classroom. This course gives you easy access to the invaluable learning techniques used by experts in art, music, literature, math, science, sports, and many other disciplines we’ll learn about the how the brain uses two very different learning modes and how it encapsulates (“chunks”) information we. Learning coins is an educational activity that introduces elementary age children to us coins and the dollar bill. Adaptedmind is a customized online math curriculum, problems, and worksheets that will significantly improve your child's math performance, guaranteed we make learning fun, game-oriented, and give you ways to get involved. Online math courses in geometry, algebra, basic math, calculus and statistics for adult learners, highschool and college students. This geometry rapid learning course is designed for students who have taken basic algebra (algebra 1 or elementary algebra) this is often the second high school math. Seven books that teach 1st to 12th grade math with a unique approach tested, proven, moneyback guaranteedgive us a call today for more information.
Stonehenge is one of the world’s most enduring mysteries, one that every passing generation wants to solve and yet no one has been able to proffer any substantive conclusion. We still don’t know why ancient people, probably the Druids who were Celtic priests, built the enigmatic megaliths. Stonehenge is located in Wiltshire, England, and I, like many others, visited it to view it myself and wonder how those ancient people were able to built it and in such a precise manner and for what purpose. The striking photo at the top left is impressive but does not clearly illustrate the grand scale of Stonehenge. Those sandstone boulders are huge and that’s just the portion above ground. It was thought that smaller bluestones (they turn a bluish hue when wet or freshly cut), imported from Wales, were placed before the massive sandstone horseshoe. This was no small feat, “The sandstone boulders, or sarsens, can weigh up to 40 tons (36,287 kilograms), while the much smaller blue stones weigh a mere 4 tons (3,628 kg).” An article published in Live Science speaks of the conclusion detailed in the December issue of the journal Antiquity, challenges earlier timeline that the smaller stones were raised first. ”The sequence proposed for the site is really the wrong way around,” said study co-author Timothy Darvill, an archaeologist at Bournemouth University in England. “The original idea that it starts small and gets bigger is wrong. It starts big and stays big. The new scheme puts the big stones at the center at the site as the first stage.” The new analysis implies that around 2600 B.C. the ancient people built the giant sandstone horseshoe first, using stone from local quarries, followed by the much smaller bluestones, likely imported from Wales. The bluestones were then rearranged at various positions throughout the site over the next millennium. There’s so much more to the fascinating article. To read it click on Live Science.
Japanese knotweed is a vigorous, clump-forming perennial, with tall, dense annual stems. Stem growth is renewed each year from creeping underground stems. It was introduced from Japan in 1825 as an ornamental plant. Although it does not produce seeds, it can sprout from very small sections of rhizomes and, under the provisions made within the Wildlife and Countryside Act 1981, it is an offence to cause Japanese knotweed to grow in the wild. Much of its spread is likely to have been as a result of topsoil movement and construction traffic.
When we look at the Moon we can easily distinguish dozens of craters caused by the collision of large meteorites or comets with its surface. The same happened on Earth’s surface mainly during its early history but very few people know that a similar event could happen again. Nevertheless the rate of crater generation on Earth has been since 4 billions of year considerably lower, but it is still appreciable. Our planet experiences from 1 to 2 impacts large enough to produce a 20 km diameter crater about once every million years on average. Even though Atmosphere and Earth’s active surface phenomena quickly destroy the impact record, about 200 terrestrial impact craters have been identified and catalogued. The diameters of these craters range from a few tens of meters up to about 300 km. With the sharp eye of Copernicus Sentinel-2 we show the most significant ones highlighting the diameter. Most of them are located on desert areas where the erosion effects of the atmosphere are less intense and of course are more visible due to the lack of vegetation. Nevertheless we got interesting examples also on highly populated places. Scientist have computed that some of these craters (diameter > 10-100km) could have caused important climate effects during the Earth’s life inducing glaciations and cooling eras with massive extinctions events (e.g.Cretaceous–Paleogene).
Electrical resistance in metals is caused by the temperature of the metal or impurities in the metal. Both increases in temperature and higher levels of impurities impede the flow of electricity through the metal material. The shape and size of the particular metal also influences its level of resistance to electrical flow.Continue Reading Metals are good conductors of electricity. Electrons in atoms hold atoms together in a crystal structure. When electrons move up to the surface of a material, they move freely to conduct electricity when a charge is applied to the substance. In metal, electrons move readily from the valence band, where they usually reside, to the conduction band, where they are free to move through the material. This allows electrons to move freely carrying an electrical charge. Because of this, metals are commonly used to make wires and other devices to carry electrical current. On the other hand, metals are not perfect conductors. Impurities in metals cause electrical resistance by keeping the electrons from moving smoothly. Increases in temperature likewise slow down the flow of electrons by causing electrical resistance. Wires that are thinner or longer also provide more resistance to electricity than thicker or shorter wires. Thin wires do not have enough electrons to carry electricity smoothly, and long wires have more distance to allow interference from electrons hitting impurities.Learn more about Electricity
We think you have liked this presentation. If you wish to download it, please recommend it to your friends in any social system. Share buttons are a little bit lower. Thank you! Presentation is loading. Please wait. Published byAmelia Kelly Modified over 4 years ago Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Active Lecture Questions for use with Classroom Response Systems Biology, Seventh Edition Neil Campbell and Jane Reece Edited by William Wischusen, Louisiana State University Chapter 34 Vertebrate Evolution and Diversity Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings 1.In Australia, marsupials fill the niches that eutherian (placental) mammals fill in other parts of the world because 1)they are better adapted and have outcompeted eutherians. 2)their offspring complete their development attached to a nipple in a marsupium. 3)they originated in Australia. 4)they evolved from monotremes that migrated to Australia about 12 million years ago. 5)after Pangaea broke up, they diversified in isolation from eutherians. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings 2.A new species of aquatic chordate is discovered that closely resembles an ancient form. It has the following characteristics: external "armor" of bony plates; no paired fins; and a suspension-feeding mode of nutrition. In addition to these characteristics, it will probably have which of the following characteristics? 1)legs 2)no jaws 3)an amniotic egg 4)metamorphosis 5)endothermy Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings 3.Why is the amniotic egg considered an important evolutionary breakthrough? It * 1)has a shell that increases gas exchange. 2)allows incubation of eggs in a terrestrial environment. 3)prolongs embryonic development. 4)provides insulation to conserve heat energy. 5)permits internal fertilization to be replaced by external fertilization. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings 4.Which of these would a paleontologist be most likely to do in order to determine whether a fossil represents a reptile or a mammal? 1)Look for the presence of milk-producing glands. 2)Look for the mammalian characteristics of a four- chambered heart and a diaphragm 3)Because animals are eutherians, look for evidence of a placenta 4)Use molecular analysis to look for the protein keratin 5)Examine the teeth Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings 5.Which of these statements about human evolution is true? 1)The ancestors of Homo sapiens were chimpanzees and other apes. 2)Human evolution has proceeded in an orderly fashion from an ancestral anthropoid to Homo sapiens. 3)The evolution of upright posture and enlarged brain occurred simultaneously. 4)Different features have evolved at different rates. 5)Mitochondrial DNA analysis indicates that modern humans are genetically very similar to Neanderthals. Evolution of Primates Chapter 6, Section 3. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Active Lecture Questions for use with Classroom Response Systems Biology, Seventh. Plant Responses to Internal and External Signals VERTEBRATE EVOLUTION AND DIVERSITY – Vertebrates have unique endoskeletons composed of: A cranium (skull) A backbone made of a series of bones called vertebrae. Compare and Contrast Why did scientist classify Pikaia as a chordate instead of as a worm Review What two aspects of evolutionary history does the cladogram. The Story of Human Evolution Vocabulary Review Ch 43 - Mammals. In animals, the characteristic of maintaining a high, constant body temperature through regulation of metabolism and. Open note quiz: amphibians & reptiles Phylum: Chordata Chapter 34. Origin of Humans (Homo sapien). The Origin of Birds Based on fossils, most paleontologists agree that the ancestor of birds was a type of small, feathered. Phylum Chordata The Vertebrates. The Phylum Chordata Includes: 1.Subphylum Cephalochordata (=lancelets) 2.Subphylum Urochordata (= tunicates) 3.Subphylum. What features the vertebrates? KEY CONCEPT Reptiles, birds, and mammals are amniotes. + Biology 11 Phylum Chordata Subphylum Vertebrata Class Mammalia: US! © 2018 SlidePlayer.com Inc. All rights reserved.
Assonance – The repetition of the same vowel sound. ‘Hear the mellow wedding bells.’ Consonance – The repetition of the same consonant sound. ‘Rap rejects my tape deck, ejects projectile/Whether Jew or gentile I rank top percentile.’ (Fugees) Alliteration – A type of consonance involving the repetition of the same consonant sound at the beginning of each word or stressed syllable. ‘Under the beckoning gaze of my smiling host, I took off my sandals and stepped into the sunlit water, which, seen from the beach, had looked as turquoise as a gemstone, but, now, seen from within and above, looked clear and transparent and overlain with a golden reticulum of racing ribbons.’ (Plato: Letters to my Son) Sibilance – A type of consonance involving the repetition of sibilant sounds such as /s/ and /sh/. An example of sibilance and of assonance around the ‘ur’ sound is, ‘And the silken sad uncertain rustling of each purple curtain.’ (Edgar Allen Poe) Phonetic symbolism – Using words with the same sounds and associated meaning, e.g. gleam, glare, glitter. Resonance – Richness or variety of sounds in poetic texture. ‘Created half to rise, and half to fall; Great lord of all things, yet a prey to all; Sole judge of truth, in endless error hurl’d: The glory, jest, and riddle of the world!’ (Alexander Pope) Cacophony – The opposite of euphony and similar to dissonance. ‘We want no parlay with you and your grisly gang who work your wicked will.’ (Winston Churchill) Anadiplosis – The repetition of the last word of one clause at the beginning of the next. ‘We also rejoice in our sufferings, because we know that suffering produces perseverance; perseverance, character; and character, hope. And hope does not disappoint us.’ (Romans 5:3) Anaphora – The repetition of a group of words at the beginning of successive clauses or lines. ‘I fled Him, down the nights and down the days; I fled Him, down the arches of the years; I fled Him, down the labyrinthine ways Of my own mind…’ (Francis Thompson) Epiphora or Epistrophe – The repetition of a word or group of words at the end of successive clauses or lines (the reverse of anaphora). ‘There is no Negro problem. There is no Southern problem. There is no Northern problem. There is only an American problem.’ (Lyndon B. Johnson) ‘Yes we can!’ (Barack Obama) Cataphora – An expression that refers to or qualifies a later expression. ‘I should have known it. You did not keep your promise.’ Symploce – The combination of anaphora and epiphora. ‘When there is talk of hatred, let us stand up and talk against it. When there is talk of violence, let us stand up and talk against it.’ (Bill Clinton) Serpentine verse – A line which ends with the same words with which it began. Epizeuxis – The repetition of the same words or words in immediate succession. ‘O dark, dark, dark, amid the blaze of noon…’ (John Milton) Epanalepsis – The repetition of the same word or words within the same clause or line, but after some intervening material. ‘The king is dead, long live the king.’ Ploce – The repetition of the same word or words in close proximity within the same clause or line for emphasis. ‘Brother to brother, blood to blood, self against self.’ (Shakespeare) Polyptoton – The repetition of the same word with a change in its grammatical form. ‘Diamond me no diamonds, prize me no prizes.’ ‘Give us this day our daily bread and forgive us our trespasses as we forgive them that trespass against us.’ Polysyndeton – The repetition of a number of conjunctions in close succession. ‘And Joshua, and all of Israel with him, took Achan the son of Zerah, and the silver, and the garment, and the wedge of gold, and his sons, and his daughters, and his oxen, and his asses, and his sheep, and his tent, and all that he had.’ Asyndeton – The omission of conjunctions. ‘I have done. You have heard me. The facts are before you. I ask for your judgement.’ (Aristotle) Hypotaxis – The use of long constructions with often multiple subordinate clauses. Produces an air of calm civilisation. Pun or paronomasia – The use of words with similar sounds or the same word in different senses. Antanaclasis – A type of pun involving the repetition of the same word in the same clause or line, but with a different sense. ‘She is nice from far, but far from nice.’ Equivoke – The intentional, ambiguous use of a word or phrase such that it has more than one meaning. Homonyms – Words with the same spelling (homographs) and pronunciation (homophones) but with different meanings. If they are pronounced differently, they are heteronyms. If they are spelt differently, they are heterographs. Polysemes are words with the same spelling and distinct but related meanings e.g. mouth of a cave and mouth of a river. Paronym – A word with the same root as another. Aposiopesis – The omission of the ending of a sentence. ‘Get out, or else –‘ Ellipsis – The omission of one or more terms that complete a grammatical sentence. ‘The people (whom) I spoke to…’ Ellision – The omission of a letter or syllable, marked with an apostrophe. Syncope – A type of elision in which a word is contracted by removing one or more letters or syllables from the middle, e.g. ne’er. Synaloepha – A type of elision in which a vowel at the end of a word is merged with the one at the beginning of the next word, e.g. th’ embattled plain. Grave – A mark indicating that the ‘e’ in ‘–ed’ is to be pronounced for the sake of metre. Solecism – An apparently unintentional impropriety of speech or violation of the established rules of syntax. Malaproprism – A type of solecism involving the substitution of one word for another than sounds similar e.g. ‘He is a vast suppository of information.’ Catachresis – The intentional misuse of a word, especially but not exclusively in the context of a mixed metaphor. ‘To take arms against a sea of troubles…’ ‘Tis deepest winter in Lord Timon’s purse.’ Antitimeria – The intentional misuse of a word as if it were a member of a different word class, typically a noun for a verb. ‘I’ll unhair thy head.’ Prolepsis – The application of an adjective to a noun in anticipation of the verb having acted on that noun. ‘She is about to bake the hot bread.’ Anacoluthon – A mid-sentence change in the grammatical structure. Enallage – The intentional and effective use of incorrect grammar. ‘Let him kiss me with the kisses of his mouth, for thy love is better than wine.’ ‘Love me tender, love me true.’ Pathetic fallacy – The ascription of human traits to inanimate nature. Similar to personification, which is however more direct and explicit. Synaesthesia – The attribution to a thing of a quality which it cannot have, e.g. a loud poem, a purple grin. ‘She smelled the way the Taj Mahal smells by moonlight.’ Tautology – The sometimes unnecessary and excessive repetition of the same idea in a line. ‘With malice toward none, with charity for all.’ Pleonasm – A type of tautology involving the use of more words than is necessary for clear expression, which may or may not add to richness of expression, e.g. ‘At this moment in time…’, ‘I am the Alpha and the Omega, the first and the last, the beginning and the end’ (pleonasm + parallelism). Hyperbaton – The separation of words that normally belong together. Anastrophe – A type of hyperbaton involving the inversion of the ordinary word order. ‘Above the seas to stand…’ Hypallage – A type of hyperbaton involving the reversal of the syntactic relation of two words. ‘Angry crowns of kings…’ Hysteron proteron – A type of hyperbaton involving the inversion of the chronology of events. ‘Let us die, and charge into the thick of the fight.’ Diacope – The repetition of a word with one or two intervening words. ‘Bond, James Bond.’ ‘Romeo, Romeo, wherefore art thou my Romeo?’ ‘To be or not to be?’ ‘Love me, love me, say that you love me.’ Tmesis – The separation of a compound word and the insertion of additional words inbetween e.g. any-old-how. Neologism – A new word. Nonce word – A type of neologism coined or used for a special circumstance or occasion only, e.g. supercalifragilisticexpialidocious. Portemanteau word – A type of neologism involving the blending of two words into a single one, e.g. ‘Tanzania’ for ‘Tanganyika’ and ‘Zanzibar’. Kenning – A compound replacement for a single word e.g. ‘morning star’ for Venus. Hendiadys – The combination of two words to express a single complex idea, to produce an effect, or to draw attention. ‘Dieu et mon droit.’ ‘Sound and fury’. ‘With friendship and peace.’ ‘You saw her bathing on the roof. Her beauty and the moonlight overthrew you.’ Hendiatris – The combination of three words to express a single complex idea. ‘Wine, women, and song.’ Tricolon – Three parallel words, phrases, or clauses. ‘Blood, sweat, and tears.’ ‘Mad, bad, and dangerous to know.’ A type of isocolon, which is a sentence is composed by two or more parts (cola) perfectly equivalent in structure, length and rhythm. ‘The future’s bright – the future’s Orange.’ Ricochet words – Hyphenated, quasi reduplicated words, e.g. nitter-natter, mumbo-jumbo. Onomatopoeia – A word that imitates or suggests the sound that it describes. Oxymoron – The juxtaposition of words which at first sight seem to be contradictory or incongruous. ‘Make haste slowly.’ Paradox – Similar to an oxymoron but less compact. ‘What a pity that youth must be wasted on the young.’ Antiphrasis – The use of a word with its opposite meaning, e.g. a giant of five foot three inches. Antithesis – The use of two opposites in a sentence for contrasting effect. Several antitheses in succession is called a progressio: A time to be born, and a time to die; a time to plant, and a time to pluck up that which is planted; a time to kill, and a time to heal… Merism – naming the parts to signify the whole. ‘For better for worse, for richer for poorer, in sickness and in health.’ Periodic sentence – a sentence that is not grammatically or semantically complete before the final clause or phrase. ‘Every breath you take, every move you make, every bond you break, every step you take, I’ll be watching you.’ Meiosis – An understatement. Litotes – A type of meiosis in which an affirmative is expressed by the negative of the contrary e.g. I am not dissatisfied. Metonymy – The naming of a thing or concept by a thing that is closely associated with it e.g. Downing Street, White Hall, Westminster, the pen and the sword as in ‘the pen is mightier than the sword’. Antonomasia – A type of metonymy involving the use of a word or phrase or epithet in place of a proper name, e.g. ‘The First Teacher’ for Aristotle. Synedoche – The naming of a thing or concept by the name of one if its parts (very similar to metonymy), e.g. a pair of hands. Parallelism – Similarity of syntactical structure in a pair or series of related words, clauses, or lines. Chiasmus – The relating of two or more successive clauses through a structural reversal. ‘By day the frolic, and the dance by night.’ ‘But many that are first shall be last; and the last shall be first.’ ‘Do not give what is holy unto dogs, and do not throw your pearls before swine, lest they (the pigs) trample them under their feet, and (the dogs) turn and tear you to pieces.’ Zeugma – The joining of two or more parts of a sentence with a single verb (or sometimes a noun), making use of both ellipsis and parallelism. Depending on the position of the verb (at the beginning, in the middle of, or at the end), a zeugma is either a prozeugma, mesozeugma, or hypozeugma. An example of a mesozeugma is, ‘What a shame is this, that neither hope of reward, nor feare of reproach could any thing move him, neither the persuasion of his friends, nor the love of his country.’ Syllepsis – A type of zeugma in which a single word agrees grammatically with two or more other words, but semantically with one only. ‘She lowered her standards by raising her glass, her courage, her eyes, and his hopes.’ Hypozeuxis – The reverse of a zeugma, where each subject has its own verb. ‘We shall fight on the beaches. We shall fight on the landing grounds. We shall fight in the fields, and in the streets, we shall fight in the hills. We shall never surrender!’ Iamb – A metrical foot (the most common) of two syllables with an unaccented syllable followed by an accented syllable. Da DUM. ‘To strive, to seek, to find, and not to yield.’ Trochee – A disyllabic metrical foot with an accented syllable followed by an unaccented syllable (the reverse of the iamb). DUM da. ‘Double, double, toil and trouble; Fire burn and cauldron bubble.’ A trochaic line is often catalectic so as to enable a masculine ending. Catalexis – The omission of one or two of the ending unaccented syllables in the final foot of a line. Masculine ending – A line ending with an accented syllable. Feminine ending – A line ending with an unaccented syllable. Hypermetric – A line with a redundant (extra) syllable. Hypercatalectic – A type of hypermetric line with the redundant syllable at the end. Spondee – A disyllabic metrical foot with two accented syllables. Spondees are often used to emphasise an iambic line. DUM DUM. Pyrrhic/dibrach – A disyllabic metrical foot with two unaccented syllables which sometimes precede or follow a spondee (the reverse of the spondee). Da da. Anapest – A trisyllabic metrical foot with two unaccented syllables followed by an accented syllable. Da da DUM. I am mon|arch of all| I survey. Dactyl – A trisyllabic metrical foot with of three syllables with one accented syllable followed by two unaccented syllables. DUM da da. Molossus – A trisyllabic metrical foot with three accented syllables. DUM DUM DUM. Tribrach – A trisyllabic metrical foot with three unaccented syllables. Da da da. Blank verse – Metered but non-riming verse. Perfect rime (true rime) – (1) The final vowel and consonant sounds are the same, (2) the sounds that precedes the vowel sounds are different, and (3) the accents on the rhyming syllables are the same. Near or half rime – There is merely consonance on the final consonants involved. Masculine rime – A rime that matches only one syllable. Feminine rime – A rime that matches two or more syllables e.g. ‘pleasure’ and ‘treasure’. Broken or split rime – A rime produced by dividing a word at the line break, leading to enjambement (the breaking of a syntactic unit across more than one line). Internal rime – A rime that is within the line. Close rime – A rime of two contiguous or nearby words. Caesura – A rhythmic break or pause in a line. ‘To err is human; || to forgive, divine.’ Hemistich – The approximate half of a line used to convey a disturbance of thought or action or a quarrelsome disagreement (hemistichomythia). Envelope – A line which both opens and closes the material. In media res – The material begins with a chronologically distant event which is however a crucial point in the narrative. Climax – The arrangement of words, clauses, or phrases in order of ascending power. ‘One equal temper of heroic hearts,/ Made weak by time and fate, but strong in will/ To strive, to seek, to find, and not to yield.’ Envoi – A short final stanza that is a concise summary of the material.
5.1 Alternating current Cells and batteries supply current that passes round the circuit in one direction. This is called direct current (d.c). The current from the mains supply passes in one direction, then reverses and passes in the other direction. This is called alternating current (a.c). The frequency of the UK mains supply is 50 hertz (Hz), which means it changes direction 50 times each second. (remember: 50th anniversary hertz) The peak voltage of an alternating potential difference is the maximum voltage measured from zero volts. A mains circuit has a live wire that is alternately positive and negative every cycle and a neutral wire at zero volts. To measure the frequency of an a.c. supply, we measure the time period of the waves then use the formula: frequency = 1/time taken for 1 cycle 5.2 Cables and plugs Plastic is used in sockets and plug cases because it is a good electrical insulator. Mains cables consist of two or three insulated copper wires surrounded by an outer layer of flexible plastic material. In a three-pin plug or a three-core cable: - the live wire is brown (live = dead = brown, CIRCLE OF LIVE WIRE) - the neutral wire is blue (blue swiss cheese = neutral) - the earth wire is green and yellow (sick is green and yellow, the earth is sick) The earth wire is connected to the longest pin and is used to earth the metal case of a mains appliance. Appliances plugged into the same mains circuit are in series with each other. The fuse in a plug is parallel to the live wire. DIAGRAM OF A THREE-PIN PLUG: A fuse contains a thin wire that heats up, melts and cuts off the current if it is too large.A fuse should have a slightly higher current than the normal current - too low would blow too soon, too high is too big to protect the appliance A fuse is always fitted in series with the live wire. This cuts the appliance off from the live wire if the fuse blows. A circuit breaker is an electromagnetic switch that opens (i.e. trips) and cuts off the current if too much current passes through the circuit breaker. A mains appliance with a plastic case does not need to be earthed because plastic is an insulator and cannot become live. The earth wire protects the user and the fuse protects the appliance and the wiring of the circuit. A residual current circuit breaker (RCCB) cuts off the current in the live wire if it is different to the current in the neutral wire. 5.4 Electrical power and potential difference The rate at which an electrical appliance transfers electrical energy into other forms is called POWER. Power = energy transferred per second Electrical power supplied (watts) = current (amperes) / potential difference (volts) Correct rating (amperes) for a fuse = electrical power (watts) / p.d. (volts) 5.5 Electrical energy and charge An electric current is the rate of flow of charge. Charge (coulombs) = current (amperes) x time (seconds) When an electrical charge flows through a resistor, energy transferred to the resistor makes it hot. Energy transferred (joules) = potential difference (volts) x charge flow (coulombs) When charge flows round a circuit for a certain time, the electrical energy supplied by the battery is equal to the electrical energy transferred to all the components in the circuit. When a charge flows in a circuit the components will heat up - this means that most electrical appliances have vents to keep them cool. 5.6 Electrical issues Electrical faults are dangerous because they can cause electric shocks and fires. Never touch a mains appliance (or plug or socket) with wet hands. Never touch a bare wire or a terminal at a potential of more than 30V. Check cables, plugs and sockets for damage regularly.
Rule by the people and for the people. This is a common phrase used by many today to describe the variety of democratic political institutions found all over the globe today. While nearly all democracies outside of Europe model the beginnings of their form of government to the United States and more specifically to the U.S. Constitution, for democracies within Europe, the beginnings are traced even farther back in time to embrace two different traditions. One of these traditions being the English Constitution primarily involving the Magna Carta, and the other tradition revolving around the French Revolution. In comparing these two as to which has ultimately proved stronger as the base for popular rule and why, one can discern that the French revolutionary tradition has accomplished this for two reasons. The first reason being due to the fact of it being more recent in historical context. Such an important event having occurred less than 300 years ago has more relevance in the minds of many political thinkers in our modern era than a similar event which occurred nearly 800 years ago. Mankind tends to believe that his ideas improve over time and thus the later the idea, the better the idea it is. The second reason for the French tradition being the base for most forms of popular rule today is due to it truly identifying and involving the three classes of the populace the aristocracy, middle-class, and poor, back then as it does today, in the political and economic process of society. While both traditions sought to limit the power of the monarch from being absolute over its subjects, it was the French revolution which gave a strong voice to those neither rich nor poor. The English tradition on the other hand, primarily involved the nobility and the monarch, much like a dispute being settled today between the millionaires on one side and the billionaires on the other. Today, like in the late 18th century during the time of the French revolution, in most advanced and developing democratic societies, the vast majority of the citizenry fall in the middle. Thus, it is their political interests and perspectives which influence political discussion and change, just as it did nearly 300 years ago.
GOT TECHNOLOGY? Then maximize its use! All you need is a computer and projector. In grade 6, students develop an understanding of ratios and rates and how to use them to solve problems. Students learn about percent and find the percent of a number using bar models as well as multiplication. As students become proficient in their understanding, they develop a number sense and the ability to visualize a model and perform mental calculations. In this MATH-O, students use the square fraction model to formulate the concept of 100% and use fraction pieces -- HALVES, FOURTHS, FIFTHS, and TENTHS -- to make the connection to percents. The fraction model serves as a meaningful reference point for measurement comparison. Students will relate benchmark percentages of 25%, 50%, 75%, 10%, 20%, 30%, 40%, 60%, 70%, 80%, and 90% to their fraction equivalents. MATH-O is Versatile! Use the slides in a variety of ways. -- Use the slides as a game to build skill fluency. -- Use the slides in direct instruction to teach skills. -- Use the slides to clarify understanding. -- Use the slides to practice and reinforce skills. MATH-O promotes the development of higher-order thinking. It calls on students to reason abstractly and quantitatively, initiate dialogue, construct algorithms, and critique the reasoning of others. Game cards for 34 students Teacher Tracking Sheet
The earliest evidence of human inhibition in Andaman is unknown to this date. Some say that Greeks and the Chinese were ones from the initiations of the humans who lived in Andaman, but these theories remain unproved. It is believed that Andaman served as a platform for migration in olden times. For some time the “Chola dynasty” ruled over Andaman and used it as a naval base. Later, in the year 1789 the British entered Andaman and set up colonies here. They also made it a naval base. The natives of Andaman did not have a very good reputation as they attacked people or good that were being transported from here. This put the British government to thoughts. The British made their colony as a way to punish and keep prisoners aloof from their native land in the mainland India. Thus, the very famous cellular jail was made by the year 1910. Mortality rate, due to diseases and the atrocities of the British was very high. During the Second World War, the Japanese occupied these islands. They ruled Andaman for four years. They performed various wrongful activities and killed nearly 750 natives before leaving in 1945. Later, the British government took over and abolished the colonies with the intention to leave India.
It’s 9000 times easier to find a ‘hot Neptune’ than a Neptune out around the ‘snow line,’ that region marking the distance at which conditions are cold enough for ice grains to form in a solar system. Thus says David Kipping (Harvard-Smithsonian Center for Astrophysics), who is lead author on the paper announcing the discovery of Kepler-421b, an interesting world about which Kipping has been sending out provocative tweets this past week. Kepler-421b draws the eye because its year is 704 days, making it the longest orbital period transiting planet yet found. The intriguing new world is located about 1000 light years from Earth in the direction of the constellation Lyra. The transit method works by detecting the characteristic drop in brightness as a planet moves across the face of the star as seen from Earth. What’s unusual here is that Kepler-421b moved across its star only twice in the four years that the Kepler space telescope monitored it. As Kipping explains on this CfA web page, the further a planet is from its host star, the lower the probability that it will pass in front of the star as seen from Earth. Kepler-421b should have had, by Kipping’s calculations, a tiny 0.3% chance of being observed in a transit. We can be happy for the discovery while also considering how tricky it will be to find worlds like it by transit methods. Image: Transit light curve of Kepler-421b. Blue and red points denote the two different transit epochs observed, offset in time by 704 days. Credit: David Kipping et al. Also known as the ‘frost line,’ the snow line in our own Solar System is the divider between the rocky inner planets all the way out to Mars, and the outer gas giants. The kind of planet you get depends in part on whether, during the early period of planet formation, the emerging planet is inside or outside the snow line. According to our current formation models, gas giants form beyond the snow line, where the temperatures are low enough that water condenses into ice grains. The planetary embryos that become the gas giants should have abundant ice grains sticking together to create worlds rich in ice and water compared to the inner system. That has major implications, of course, because we have discovered a large number of ‘hot Jupiters’ and Neptune analogues that orbit far inside the snow line in their respective systems. That makes for migration scenarios where gas giants forming in the outer system move inward as the result of likely gravitational encounters with other worlds. Kepler-421b, however, orbits its K-class primary at a distance of about 177 million kilometers, a gas giant that may never have migrated, and the first example of such ever found using the transit method. The snow line moves inward over time as the young planetary system evolves, and Kipping and team’s calculations show that when this system was about three million years old, early in the era of planet formation, its snow line should have been at about the same distance as Kepler-421b’s present location. The planet is roughly the size of Uranus, about four times the size of Earth, which may be an indication that it formed late in the planet formation era, at a time when not enough material was left in the system to allow it to become as large as Jupiter. But is Kepler-421b truly an ice giant or could it actually be a large, rocky world? The evidence strongly favors the former. From the paper (internal citations deleted for brevity): Although calculating detailed formation scenarios for Kepler-421b is outside the scope of this work, simple arguments suggest Kepler-421b is an icy planet which formed at or beyond the snow line. With a radius of roughly 4 R⊕ and a mass density of at least 5 g cm-3, a rocky Kepler-421b has a mass of at least 60 M⊕. Growing such a massive planet requires a massive protostellar disk with most of the solid material at 1-2 AU. Among protoplanetary disks in nearby star-forming regions, such massive disks are rare. Thus, a rocky Kepler-421b seems unlikely. And as to the place of formation: For Kepler-421b, in situ formation is a reasonable alternative to formation and migration from larger semi-major axes. Scaling results from published calculations, the time scale to produce a 10-20 M⊕ planet is comparable to or larger than the median lifetime of the protoplanetary disk. Thus formation from icy planetesimals is very likely. If significant migration through the gas and leftover planetesimals can be avoided, Kepler-421b remains close to the ‘feeding zone’ in which it formed. To place the planet in context, consider that Mars orbits the Sun every 780 days, as compared to Kepler-421b’s 704 day orbit (around, as mentioned above, a K-class star that would be cooler and dimmer than the Sun). The researchers’ calculations indicate a temperature of about -135 Fahrenheit (180 K). At least one recent paper, cited by Kipping and colleagues, suggests that planets near the threshold of the snow line may be common, but finding them by transit methods will be difficult because of the low transit probability. As for radial velocity detection, the planet poses what the paper calls “a significant challenge to current observational facilities,” but determining the mass of worlds like this could help us understand the relationship between mass and radius as we move further from the parent star. The paper is Kipping et al., “Discovery of a Transiting Planet Near the Snow-Line,” accepted by The Astrophysical Journal and available as a preprint online.
This Tutorial contains following Attachments: - SOC 120 - Week 4 - DQ 2 - Food Justice Food Deserts.docx SOC 120 Week 4 DQ 2 Food Justice/Food Deserts The purpose of this discussion is to offer you the opportunity to debate the issue of food justice and food deserts. Food deserts are significant issues in poorer neighborhoods in the United States. In many of these neighborhoods, the only access to food is through local convenience stores or fast food restaurants. This severely limits the options for the poor to have access to fresh, wholesome food and has been evidenced as a key reason for the obesity epidemic in the United States. This issue is encompassed in the overarching topic of food justice, which also highlights public access to genetically modified or organic foods and the issues of equal access to positive food options in light of public health and social inequality. Prepare and post a response to the following prompt: Read the Hilmers article, Neighborhood Disparities in Access to Healthy Foods and Their Effects on Environmental Justice. Assume that your town is a food desert and you would like to do something about it. Prepare an argument to present to your local town council that outlines an idea to offer healthy food options to your town. Use at least one ethical theory or perspective to support the moral or ethical reasoning for why this program should be implemented. Your initial post should be at least 250 words in length. Support your claims with examples from the required resources and/or other scholarly sources, and properly cite any references in APA style as outlined in the Ashford Writing Center. Respond to at least two of your classmates’ posts by Day 7. Carefully review the Discussion Forum Grading Rubric for the criteria that will be used to evaluate this Discussion Thread. Write a reviewYour Name: Your Review: Note: HTML is not translated! A B C D F Enter the code in the box below:
When NASAs Stardust capsule flew within 149 miles of the comet Wild 2 in January 2004, its main goal was to collect particle samples from the comets coma—the cloud of frozen dust and gases that trails the comets nucleus. This week, NASA released its initial findings, which have changed scientists perception of how comets form. Comets have long been thought of as frozen chunks of rock and ice that formed in the cold outer reaches of space. But upon analyzing Stardusts samples, scientists observed that at least 25 percent of the particles retrieved originated from the ultra-hot center of the solar system. This finding suggests that comets are more diverse than previously thought. It also provides new insight into the importance of the X-wind, the magnetic jetstream most likely responsible for carrying high-temperature particles to the outer solar system, where comets form. NASA is far from finished with the analysis of Stardusts samples (the first space particles successfully returned to Earth since a Russian craft brought back moon rocks in 1976), and the space agency is asking for help from the public to continue the analysis. Check out our April story "Dust Busters" to find out how to help. —John Mahoney
Metaphors are powerful cognitive tools in English language. The purpose of metaphors in the educational setting is to simplify the knowledge for the learners that is in abstract terms. Gestures are the material carriers of thought and they work on representing abstract concepts into a visual mode. Speakers often draw on multimodal resources and they put to use verbal and manual metaphors for a more expository cause. Writers with English as a second language (ESL) often struggle with conventions of English Academic Writing (EAP). To be able to relate the knowledge of English conventions to ESL students is a very big challenge. Literary experts have pointed out that metaphors are very important tools that help people to understand and comprehend unfamiliar and the intangible world through its mapping and coordination into a more physical and familiar world. In the educational setting they do a very helpful role of helping students to comprehend scientific knowledge. It is viewed as a framework that is rich with possibilities for both, students and teachers. In English language the metaphor is always used in a specific context where it is understood by a specific group of people. When we talk of the educational setting, a comprehension of each other with thoughts and conceptualisation of each other’s expression is important. But at the same time they are intertwined and hence the need arises for a mediational role of metaphors for solely the expository purpose. In an environment where the ESL writers need to be trained on academic writing conventions, the use of and metaphors play a very important role. They serve as an aid to depict a larger semantic meaning to the students so as to enhance their understanding. Metaphors become evident in the language of the writer, speaker and trainer in the case of interaction and writing of ESL writers. In the case of abstract concepts and topics the outburst of gestures and metaphors presented a very different understanding of the topic. Thus, it can be said that they should be used liberally and on hands , particularly when the writer or the reader of the academic text belongs to the English as a second language category.
UEN Security Office Technical Services Support Center (TSSC) Eccles Broadcast Center 101 Wasatch Drive Salt Lake City, UT 84112 (801) 585-6105 (fax) Educational Technology - (Grades 6-8) 1 class periods of 45 minutes each This is an ESL lesson, it can fill in as a review for other students learning about Prepositions. Students use a power point presentation as a drill and practice program. They are able to review reading a map and the form and functions of Prepositional Phrases. The Curriculum tie is difficult to decide because the state doesn't have specific curriculum for ESL students. This is to be used with intermediate ESL students. You will need a computer with Microsoft Power point on it, more computers if you are going to pair them into groups for the activity. If you want to use it as a whole class activity you will need a video projector that allows you to view the presentation on a large board. You will also need the file with the worksheet, and the presentation. You need to know power point and to have taught your students the form and functions of Prepositional Phrases. Form and Functions of Prepositional Phrases. Map reading skills How to use a mouse, keyboard, and the basics of guiding powerpoint. The Students will be able to define a prepositional phrase and give you examples of some phrases. They will be able to recognize the form of the phrase and how to use it in a sentence. They will be able to use powerpoint to navigate their way through the worksheet and the activity itself. Whole Class Activity You need to set up the projector and the computer so the whole class can see the presentation. You will also need to give each student a copy of the Map and the Worksheet. Start the presentation, and read the instructions to the students. Review the instructions so you know each student understands what is required of them. To start you can have students take turns answering the questions and clicking the buttons to move through the slides and the worksheet. Guide the students if they aren't understanding the material. Help them if they need it, show them on the Map. Also, It helps to write a list of prepositions on the board to help them out, it gives them a review list if they need it. When they are done they can hand in the worksheet for grading. Individual Drill and Practice Make sure the student has the worksheet and is able to guide themselves through the program. It helps if the teacher is near by to answer any questions the student might have. This is created to be part of a larger lesson on Prepositional phrases, it is only a review for what they have already learned. This is designed for English Language learners, and is easy to move around the program. With guidance I think any student will be able to complete the assignment, hopefully, successfully. It could be attatched to a full length lesson on Prepositional Phrases, or a lesson on Map reading. AS long as the student can guide thier way through the presentation you know that they understand the computer aspect. The worksheet will allow you to know if they have mastered the grammar aspect. Power Point, Existing Prepositional Phrase Lesson created by Myself, Visio 2000 Word Perfect
Forces that alter or interfere with perception – including state of attention, muscle tension, age, practice, distractions and physical fitness – affect reaction time. Because reaction time depends on the ability to perceive stimulus and respond, these factors affect the speed of responses and skew judgment about choosing between responses.Continue Reading Much experimentation in reaction time studies human response to traffic and other rapidly changing situations. In those cases, subjects must first prove that they can perceive a stimulus and then react to it. A subject receives a rating according to his raw reaction times factored against a base state calculated from preparation for testing, life experience, age, physical fitness and state of attention. Scientists commonly test to measure reaction times for four different types of reactions: reflex, simple, complex and discriminative. Because reflex reactions, such as eye blinks, are instinctive, they usually take the shortest time. Simple reactions, which also have short reaction times, are those to ordinary, everyday stimuli, such as the response to a traffic light turning from red to green. Complex reactions, where a subject has to choose among multiple responses, have longer reaction times and involve choosing the appropriate response based on experience, but without advanced planning. The most complex reactions with the longest reactions times are discriminative reactions, where subjects must choose from multiple responses which are not practiced or habitual.Learn more about Muscles
A little info on energy pathways In the human body energy production is centered around ATP. Our muscles can generate ATP by the use of three metabolic pathways. These pathways are the ATP/CP pathway, Glycolytic pathway and Oxidative pathway. Muscle cells can use one or a combination of the three pathways to generate energy. Different forms and durations of exercise cause different demands on the body leading to different ways the body has to generate ATP. The ATP/CP pathway is anaerobic meaning it does not require oxygen to produce the energy. This pathway is used in exercise that requires quick explosive movements that are high intensity but short in duration. Examples include throwing, jumping, and weightlifting. Since a limited amount of ATP is stored in muscle cells the body must replenish ATP through the ATP/CP pathway. All forms of exercise use this pathway first regardless of the intensity or duration but it only takes under 2 seconds for ATP stores to become depleted and less than 60 seconds for the CP stores to become completely depleted. The Glycolytic pathway is the second pathway that comes into play. Similarly to the ATP/CP pathway the Glycolytic pathway is also anaerobic. This pathway works by breaking down stored carbohydrates in the muscle cells (glycogen) or available glucose in the blood stream to convert ADP to ATP. The limiting factor becomes the byproduct of the ADP-ATP conversion which is lactic acid. This pathway is the main form of energy production between the 60 and 80 second mark. The Glycolytic pathway is used mainly during weight lifting repetitions, repeated jumps or throws lasting under 80 seconds in duration. Finally the Oxidative pathway, the only pathway that is aerobic meaning it requires oxygen to produce ATP. This process produces the most ATP however it also takes the longest. Endurance training uses this form of energy. Long distance running, biking or rowing will cause this energy pathway to come into use. This pathway will continue for the duration of the exercise breaking down carbohydrates and fat until they are no longer available and then it will start breaking down muscle (amino acids) for energy.
What is the Human Circulatory System? The main organ of the circulatory system is the Human Heart. The other main parts of the circulatory system include the Arteries, Arterioles, Capillaries, Venules, Veins and Blood. The lungs also play a major part in the pulmonary circulation system. Functions of the circulatory system The function of a humans circulatory system is to transport blood around the body. The blood itself also carries numerous other substances which the body requires to function. The main substance being Oxygen, carried by a protein called haemoglobin, found inside red blood cells. White blood cells are also vital in their role of fighting disease and infection. Blood contains platelets which are essential for clotting the blood, which occurs follwing an injury to stop blood loss. Blood also carries waste products, such as Carbon Dioxide away from muscles and organs in order to be dispelled by the lungs. Systemic & pulmonary circulation There are three circulatory processes occurring simultaneously within the body. Firstly systemic circulation carries blood around the body, pulmonary circulation carries blood to the lungs and coronary circulation provides the heart with its own supply of blood. At the start of the blood circulatory cycle the heart pumps oxygenated blood out of the left ventricle, through the Aorta (the largest artery in the body). The aorta divides into smaller arteries, then arterioles and finally into microscopic capillaries, found deep within muscles and organs. Here the Oxygen (and other nutrients) passes through the thin capillary walls, into the tissues where it can be used to produce the energy muscles require to contract. A waste product of energy production (metabolism) is Carbon dioxide and in order to be removed, it too passes across the walls of the capillaries, into the blood stream. The blood continues back towards the heart, through venules and then veins, into the right atrium. Once blood returns to the heart it is then pumped from the right ventricle through the Pulmonary arteries to the lungs, where the waste carbon dioxide can be expelled and more Oxygen collected. The Pulmonary vein carries oxygenated blood back to the left atrium of the heart, where the cycle starts again.
Lamellibrachia luymesi is a species of tube worm in the Siboglinidae family. It is found in the Gulf of Mexico in deep-sea cold seeps where hydrocarbons are leaking from the seafloor, typically at depths of 1,600 to 2,600 feet. This species can reach lengths over 10 feet, and grows very slowly, living more than 250 years. It forms biogenic habitat by creating large aggregations of hundreds to thousands of individuals. Living in these aggregations are over a hundred different species of animals, many of which are found only at these seeps. This worm is entirely reliant on internal, sulfide-oxidizing symbionts for its nutrition. It provides bacteria with hydrogen sulfide and oxygen by taking them up from the environment and binding them to a specialized hemoglobin molecule. Unlike tubeworms that live in hydrothermal vents, this species uses a posterior extension of its body called the root to take up hydrogen sulfide from the seep sediments. It may also help fuel the generation of sulfide by excreting sulfate through their roots into the sediments below the aggregations. Image Caption: Close-up photograph of the symbiotic vestimentiferan tubeworm Lamellibrachia luymesi from a cold seep at 550 m depth in the Gulf of Mexico. The tubes of the worms are stained with a blue chitin stain to determine their growth rates. Approximately 14 mo of growth is shown by the staining here. Credit: Charles Fisher/Wikipedia(CC BY 2.5)
Traditionally, the sun has provided energy for practically all living creatures on earth, through the process of photosynthesis, in which plants absorb solar radiation and convert it into stored energy for growth and development. Scientists and engineers today seek to utilize solar radiation directly by converting it into useful heat or electricity. Two main types of solar energy systems are in use today: photovoltaics, and thermal systems. There is a great deal of opportunity for using these systems in the state of Pennsylvania, and ongoing work at Penn State is seeking to improve the available technology and increase the utilization of solar energy systems in the keystone state. Photovoltaic systems convert solar radiation to electricity via a variety of methods. The most common approach is to use silicon panels, which generate an electrical current when light shines upon it. Penn State University is involved in several projects to demonstrate and encourage the use of solar energy at appropriate locations within Pennsylvania. Solar photovoltaics are especially valuable for remote rural applications where it would be prohibitively expensive to supply electricity from a utility line. Solar thermal systems Solar Thermal Systems seek to store heat from the sun that can be used for a variety of purposes. Many different approaches can be employed here, including active systems, such as solar hot water heaters, and passive systems, in which careful engineering design results in a building that automatically stores and utilizes solar energy. Greenhouses are a prime candidate for passive solar design, in which they collect solar energy on sunny days in winter and utilize it to keep the house warm at night. The main advantages of solar energy are that it is clean, able to operate independently or in conjunction with traditional energy sources, and is remarkably renewable. The main disadvantages are that it is currently more expensive than traditional energy, and the availability of solar radiation varies from day to day, and from season to season. In fact, some parts of Pennsylvania are among the cloudiest spots in the United States. In spite of this, there is still opportunity for using solar energy effectively in Pennsylvania.
The concept of how babies learn to speak is an elusive and mysterious one, even for scientists who yearn to understand how young children are able to master the complexities of language - a difficult enough task for the adult brain and the most powerful computers. In a recent series of experiments, psychologists have found that infants seem to remember relatively complex words, even when they only hear those words in tape-recorded stories without the benefit of any other stimuli. Such findings suggest that babies memorize words that occur frequently in speech - an important prerequisite for learning language. Although much work has been conducted to investigate how children learn the meanings of words, little research has been aimed at learning how infants focus on the sounds of words, says Peter Jusczyk, professor of psychology at Johns Hopkins University, who co-authored the paper with Elizabeth A. Hohne, a psychologist at AT&T Labs in Holmdel, N.J. In their work, the two scientists recorded women narrating three different children's stories; these contained words like "peccaries" and "python", and each lasted about 10 minutes. Then the researchers visited the homes of 15 eight-month-old infants, playing the stories to them every day for 10 days. By the end, the babies had heard each story 10 times. The psychologists identified the 36 words that occurred most often in the stories. Then they arranged those words in lists of 12 words each. Two weeks after the final visit to the infants' homes, the babies were brought to Jusczyk's lab at Johns Hopkins. One at a time, they listened to the lists containing the words that occurred most frequently in the stories. Then they listened to lists of other, similar-sounding words that did not occur in the stories. A light flashed above the speaker through which the tape recording was played. When the infants looked at the light, the word lists began and continued to play until the infants looked away. Thus, the researchers determined how long the infants had listened to specific lists of words. "What we found was that the babies listened longer - significantly longer - to the lists of words from the stories," Jusczyk says. Previous research using this technique has shown that infants tend to listen longer to words that are more familiar to them. The researchers, however, wanted to make sure the infants were not listening longer to the story words simply because they found them more interesting, so they brought a new group of infants to the lab who had never heard the stories on tape. When those infants heard the lists of both story and non-story words, they showed no preference and actually listened slightly longer to the non-story words. "That showed us that the experience the babies had had at home listening to the stories had an impact on what they really remembered," Jusczyk explains, noting that the infants learned the words even though they never had any personal contact with the women who narrated the stories. At about 18 months, a child's vocabulary and grasp of language suddenly expands. Scientists don't know why. One possible explanation is that children may begin storing the sounds and meanings of words while they are infants, and suddenly, at a year-and-a-half, they are able to connect these words with meanings. "It's sort of like working on a puzzle. You get a few pieces and then everything falls into place," says Jusczyk, adding that this study shows that infants may store the sounds of words, even when they have not yet learned the meanings.
How climate change is forcing us to rethink national parks A study of yellow cedars in Alaska's Glacier Bay National Park and Preserve suggests that climate change calls for new models of conservation and preservation. After studying a designated reserve of yellow cedars in Alaska, a group of scientists are suggesting that a conservation method from the past be abandoned. A team of researchers with the Stanford School of Earth, Energy and Environmental Sciences published a study on climate change Thursday in the journal Biological Conservation that has turned typical environmental preservation on its head. In their study, the researchers found evidence that even currently healthy yellow cedars in the Glacier Bay National Park and Preserve can expect “future climate-induced dieback.” Early springtime reduces the snow cover on the trees’ shallow roots and exposes them to the cold, killing the trees. So although the trees in the park are currently healthier than trees outside the park, the “reduced crowns and browned foliage in yellow-cedar trees” indicate early signs of the dieback moving toward the park. Climate change does not respect park borders, so the traditional conservation approach of simply setting land aside to protect biodiversity in the form of a reserve or park is no longer enough, argues Lauren Oakes, lead author of the study. Instead, Dr. Oakes suggests “adaptive management strategies” that keep humans involved in the conservation process and account for climate-induced habitat changes. “To balance the many values people hold for nature and to maintain the many benefits that people derive from nature, we’re going to have to do things differently under climate change,” Oakes told The Christian Science Monitor. “Setting aside lands to protect biodiversity may no longer be sufficient to sustain species vulnerable under climate change because we are seeing species like the yellow cedar impacted by climate change on our federal lands, mostly restricted of human activity.” The researchers suggest the first step may be place-based education for the local public and park managers. “Individuals’ views of protected areas form the foundation of perspectives on whether or not to intervene in protected areas,” Oakes further explained to the Monitor. She believes understanding local views of protected areas is important because it “may influence their perspective on adopting new management strategies” at both the local and national level. It may seem counter-intuitive, but Oakes and her colleagues suggest investing more time and energy into protected areas to achieve a higher standard of wilderness, or naturalness. Park rangers and managers should use this public insight to influence their conservation practices. “If we know we are losing some species from the lands in which human activity is most restrictive, and people value the continued existence of that species, the changes occurring inside protected areas may put an imperative on managers of actively managed lands to do things differently,” says Oakes. Oakes says the responsibility of park managers should not be understated, because they represent the importance of a socio-ecological approach. The team of researchers interviewed 45 different land managers in the Glacier Bay area, and the interview results suggest a direct correlation between individual attitudes and potential conservation methods. Participants who viewed the protected areas as "natural" and separate from humans, “were more likely to oppose new interventions in the protected areas, regardless of how necessary they may be." In contrast, the participants who viewed humans as being "a part of" nature, viewed intervention in protected parks more favorably. Dr. Eric Lambin, a professor at Stanford and co-author of the study, says these results prove the interdependence of ecological and social techniques. “We often think about an organization and its missions, but forget that day-to-day decisions are made by people who carry their own value systems and perceptions of risks,” he said in a press release.
As the weather warms and the days grow longer, predictably, veterinarians experience a rash of phone calls from panicked owners concerning the sudden onset of odd behaviors in their pets. Oftentimes, they report a decreased appetite, whining, crying, frequent urination or odd postural reactions. A spring virus? An injury? Infection? The first question asked by your veterinarian will likely be "Is your pet spayed?" If the answer is "No," then read on for a lesson in your pet's reproductive cycle. Your dog's reproductive cycle is regulated by hormones produced both in the brain and the ovary. These hormones not only produce the changes in the reproductive organs needed for pregnancy but cause some dramatic departures in your pet's normal behavior as well. Hormones influence fertility and reproductive behavior in both the dog and the cat, although their heat and reproductive cycles vary by environmental and breeding behavior.Canine Reproductive Cycle There are basically three phases to the female dog's reproductive cycle: the follicular, luteal and quiescent phases. Each phase is under the influence of the dominant hormone produced. It is really an amazing system of timing and feedback from the brain to the ovary and back. The dog's ovary is a collection of eggs in different stages of maturation. Each individual egg is actually enclosed in a tiny fluid filled sac called a follicle. A hormone produced by the pituitary gland at the base of the brain sends a signal for the eggs to develop within their follicles. This hormone is called follicle stimulating hormone (FSH) and causes the eggs to mature. Once the eggs have fully developed, they too have the ability to produce their own hormones. Follicles produce a hormone called estradiol 17B, and it is the dominant influence on the "follicular phase" of the reproductive cycle. In the luteal phase, the pituitary gets busy again and secretes a hormone called luteinizing hormone(LH). The production of this hormone is triggered by the maturing follicles. LH acts on the follicle to stimulate ovulation, the time when the egg breaks through the follicle so that it can be fertilized. The egg then begins to travel down the Fallopian tube and the empty follicle undergoes its own physical change. It becomes a corpus luteum, the Latin name for "yellow body." It is named so because once the egg has ruptured, the follicle enlarges and turns an easily recognizable yellow color in contrast with the less mature follicles. The corpus luteum now has its own job to do, and that is to produce progesterone, the hormone of the luteal phase. It is in this phase that your dog exhibits mating and receptive behavior or signs of heat. You may see swelling of the vulva and bloody vaginal discharge that signal her fertility to potential mates. Since dogs have multiple births, several eggs mature and are released at the same time. If fertilized, the eggs will implant on the uterine wall. This implantation results in a continued release of progesterone, the hormone responsible for maintaining pregnancy. If none of the eggs is fertilized, the body becomes aware that no eggs have implanted and progesterone is no longer released. This results in the quiescent or quiet phase. This stage may last several months, in which the dog will show no signs of sexual behavior. Most dogs cycle twice a year in this manner, but it is safe to say that the reproductive cycle is unique to the individual. There will be variations in the number of heat cycles per year, the level of behavioral change, and interest in mating.Pregnancy If your pet is bred and a pregnancy results, the average length of gestation is 63 days. This may vary a bit, but most people start to count the days of gestation from the day of the first breeding. If you only have a suspicion your pet may be pregnant and want to know for sure, your veterinarian can help make that determination. During your pet's pregnancy, progesterone is the dominant hormone and is essential for maintaining the proper conditions in the uterus for the growth of the babies. About 10 days before puppies are born, the progesterone level falls and estrogen levels start to rise. As these hormone levels change, you will see physical and behavioral changes that signal labor and delivery. Your pet may seek seclusion, exhibit nesting behavior and her appetite may decrease. She may be restless. Most dogs pant. Mammary glands will distend and you will be able to express milk. A general guideline for monitoring the arrival of puppies is when your pet's rectal temperature falls below 100 degrees Fahrenheit, you can expect the onset of labor within 24 hours. If the names of some of these hormones seem familiar to you it's because the very same hormones also regulate the human female reproductive cycle. While women are not constructed for litters the way dogs and cats are, the reproductive physiology isn't very much different. You may have more in common with your pet than you thought.
Making a Scaffold After cell expansion, the next step in engineering a tissue or organ is to create a mold, or scaffold, in the shape of the tissue. Electrospinning is one technique used to make scaffolds for blood vessels, as well as muscles and tendons. The technique involves dissolving a biomaterial into a solvent, loading it into a syringe, and then applying a high voltage to the solution as it is slowly ejected from the syringe. Watch a video example of electrospinning below: At some distance away, there is a collection mandrel that is grounded so that when the charged solution leaves the syringe, it is attracted to the mandrel. You can actually see in this video the fibers shooting from the syringe to the mandrel and forming a tubular structure.
Here’s a problem: Tiny antennas for big wavelengths. Normally an antenna needs to be at least one-half the size of the signal wavelength it’s intended to send or receive. For example, if the wavelength is 300 MHz, the antenna should be about a half meter wide. So, how do you make much smaller antennas match big wavelengths? By having clever designs that make use of materials constructed with special properties (metamaterials) to capture or augment a radio signal. In this case a team of researchers from the National Institute of Standards and Technology (NIST, Colorado, USA), Boeing Research & Technology (Seattle, USA), and the University of Arizona (Tucson, USA) developed an antenna only 65 mm on a side. The top surface is a copper sheet on which is printed the metal antenna circuitry. The key piece is a so-called “Z element” on the back of the copper sheet – a Z-shaped strip of copper metamaterial with an electro-magnetic inductor at the center. This catches, stores, and re-radiates the signal that normally would be lost through reflection in such a small antenna. One of the side benefits of using the ‘metamaterial’ Z element is that it can be ‘tuned’ to handle a variety of wavelengths (frequencies). Such flexibility in a small device has many advantages. It also indicates that as the size of the antenna continues to shrink, it will still scale well against the various wavelengths needed for applications. “The purpose of an antenna is to launch energy into free space,” explains NIST engineer Christopher Holloway, “But the problem with antennas that are very small compared to the wavelength is that most of the signal just gets reflected back to the source. The metamaterial makes the antenna behave as if it were much larger than it really is, because the antenna structure stores energy and re-radiates it.” Conventional antenna designs, Holloway says, achieve a similar effect by adding bulky “matching network” components to boost efficiency, but the metamaterial system can be made much smaller. Even more intriguing, Holloway says, “these metamaterials are much more ‘frequency agile.’ It’s possible we could tune them to work at any frequency we want, on the fly,” to a degree not possible with conventional designs. It’s no surprise that the details of the metamaterials nor the electronics involved are not disclosed. This sort of miniaturization usually has its first use in military and intelligence applications. (The spooks get it first.)
A greenhouse is a structure, generally made of glass, designed for the cultivation or protection of plants. One of the most critical tasks in greenhouse maintenance is controlling condensation. Other People Are Reading Condensation refers to the formation of liquid drops of water from water vapour. In greenhouses, condensation generally appears on plants and greenhouse coverings. Condensation is a symptom of high humidity and can lead to significant problems, including germination of fungal pathogen spores, including Botrytis and powdery mildew. Moreover, condensation that forms on the greenhouse covering can fall and spread plant pathogens from plant to plant by splashing soil and plant debris. Plant surfaces must be kept above the dew point to avoid condensation. To do this, install a heating distribution system near or below the plants. There are several heating systems available. Pipe heating is perhaps the most common and involves installing a network of metal or plastic pipes that distribute hot water. Pipes are most effective when placed between the middle and bottom of the plant. Warm floor heating provides heat through a hot water system below the soil or below the concrete floor surface. One of the main advantages of warm floor heating is that the heat rises, which provides better air circulation than some heating systems. Finally, air heating refers to a system of heating that uses forced air heaters placed overhead, with heat distributed via fans. Improving air circulation will reduce condensation by evaporating the condensation. Improved air circulation is generally achieved using horizontal air flow fans or a perforated poly tube system. These tools should be used in combination with proper ventilation. Air circulation can also be improved by using open mesh or slatted benches, as opposed to solid benches, and increasing the space between plants. Part of condensation control involves knowing the humidity inside your greenhouse. Humidity can be measured using a sling psychrometer. Psychrometers are available at most greenhouse supply and scientific equipment stores. Humidity pocket meters and humidity pens are also available and are generally cheaper than psychrometers. Ideal humidity levels will differ depending on specific climate conditions and plants. - 20 of the funniest online reviews ever - 14 Biggest lies people tell in online dating sites - Hilarious things Google thinks you're trying to search for