... have used perfumes for thousands of years, but there is a basic difference between perfume and pheromones. Pheromones are produced by the body and usually do not smell at all pleasant, whereas perfumes are either synthesized or extracted from natural products and are employed because of their pleasant smell. Scientific research suggests that there are human pheromones for both the male and the female. Females have a better developed sense of smell and testing indicates that they are more responsive to male pheromones than the reverse. Research over the years has found that the male pheromones belong to a class of compounds called steroids, in particular derivati ...
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... Le quatrieme virus est Ebola-Reston, a cause la maladie dans les primats non humains, mais pas chex l'homme. Il y a aussi le question, ou le virus d'Ebole se trouve? Les scientists, est medcins, ne savons pas. Il croien que le virus est devenu d'une centre serveru animal, comme un chauff souris, un souris est probablement un singe. L'origine exacte, les emplacements et l'habitat normal du virus d'Ebole rest inconnus. Comment Est ce-que le virus nous tuer? Cette question est la plus populair est aussi le plus interesant. Tous les victims d'Ebola, mort a cause de hemorragique. Quand quelq'un contract le virus Ebola, ils restant vivent pour h ...
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... acid. Sunlight increases the rate of most of these reactions. Rainwater, snow, fog, and other forms of precipitation containing those mild solutions of sulfuric and nitric acids fall to the earth as . Water moves through every living plant and animal, streams, lakes, and oceans in the hydrologic cycle. In that cycle, water evaporates from the land and sea into the atmosphere. Water in the atmosphere then condenses to form clouds. Clouds release the water back to the earth as rain, snow, or fog. When water droplets form and fall to the earth they pick up particles and chemicals that float in the air. Even clean, unpolluted air has some particles such as dust or p ...
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... lid at the outer corner of the . After passing over the , the liquid from the gland is drained into the nose through the tear duct at the inner corner of the . Heavy laughter or crying causes muscles in the upper lid to squeeze the lachrymal gland. This produces tears that flow too fast to be drained away. The lashes catch many flying particles that otherwise would enter the . As further protection, the lids automatically close when an object suddenly moves close to the . The eye is made of 3 coats, or tunics. The outermost coat consists of the cornea and the sclera. The middle coat contains the main blood supply to the eye and consists of the choroid, the c ...
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... in the ozone layer are forming over the polar regions and these are increasing in size annually. Paradoxically, ozone is toxic! Undiluted ozone is bluish in colour. Liquid ozone is bluish-black, and solid ozone is violet-black. Oxygen is very reactive and capable of combining with most elements. It is essential for respiration of all plants and animals and for practically all combustion. history of oxygen Leonardo da Vinci suggested that air consists of at least two different gases. Before then, air was felt to be an element in its own right. He was also aware that one of these gases supported both flames and life. Oxygen was prepared by several w ...
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... story. One clue is that patients have excess amounts of sodium and chloride in their sweat making it vey salty . At the University of North Carolina researchers found that salt imbalance caues thick mucus to accumulate in the patients lungd. High level of salt in lung cells draw water out of the mucus causing it to thicken.The level of salt in a cell is determained by the movement of ions across the cell membrane.Ions are carried across call memebranes by protein channels embedded in the cell membrane. Since the stucture and functions of proteins are determained by genes problems with ion transport can be assumed to have a genetic basis. In 1989 an American Cana ...
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... into the carpet, thus completing the circuit. AMAZING ELECTRONIC FACT: If you scuffed your feet long enough without touching anything, you would build up so many electrons that your finger would explode! But this is nothing to worry about... unless you have carpeting. Although we modern persons tend to take our electric lights, radios, mixers, etc. for granted. Hundreds of years ago people did not have any of these things, which is just as well because there was no place to plug them in. Then along came the first Electrical Pioneer, Benjamin Franklin, who flew a kite in a lightning storm and received a serious electrical shock. This proved that lightning wa ...
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... one day be judged as crimes against humanity and nature, which leads to the question: What kind of world do you want to live in? Our ancient habit is to stumble backwards into the future. We feel that we as individuals make little difference, as if history and the future just happen at us. Obscure plans, which have guided people forward in the past, have now rendered themselves useless. There are no known maps to show pathways into the future. We’ll need to consider back to our hearts, common sense and basic human capabilities. We’ll need to consider the deep issues at stake and make deep choices about them. This idea of disaster is actually an aide ...
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... is disrupted by human activity. People of the world are putting more than 5.5 billion tons of CO2 into the atmosphere every year. 75% of this is caused from the burning of fossil fuels. These fuels are burnt all the time to run factories, power plants and vehicles. The main sources of CO2 emissions are electric utilities, residential buildings, industry and transportation. The other 25% is induced by the destruction of the world's forests. The reason for this is that there are less trees and plants to take in the CO2 but there is just as many, if not more, humans and animals to breathe it out. The amount of CO2 in a planet's atmosphere affects the temperature ...
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... in the 1970's in a set aside special national park under full protection. Politicans and bureaucrats seem to be obsessed with numbers and not trends. Let me illustrate this with tigers. There are frequently requests as to the exact number of tigers, or a tiger subspecies left in the world. That tells you that there are people that care. But there are so little tigers left that we can not even keep track of them. We should look at the trend that the population is taking, rather than the number as a slice in time. Just as you might say of a young member of the Hunt family, that they were very wealthy. A hypothetical individual was 24 years old and had $1,000,000. ...
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