... consists of some fossils that represent certain genus or family, and the whole sequence often covers a span of tens of millions of years. A lineage like this shows obvious intermediates for every major structural change, and the fossils occur roughly (but often not exactly) in the expected order. However, usually there are still gaps between each of the groups. Sometimes the individual specimens are not thought to be directly ancestral to the next-youngest fossils (e.g. they may be "cousins"" or "uncles" rather than "parents"). However they are assumed to be closely related to the actual ancestor, since the have similar intermediate characteristics. Where Does ...
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... in people with Alzheimer's or other diseases where brain cells degenerate, he commented. Goldman noted that the use of drugs to stimulate proliferation of new brain cells will probably result in a more successful strategy than attempting to grow the cells outside the body and then placing them back into the brains of patients, as some scientists have suggested. Goldman, of Cornell University Medical College in New York, and colleagues surgically extracted brain cells from the hippocampus of eight living male patients, ranging in age from 5 to 63 years, while they underwent surgery for another reason. The investigators isolated stem cell ...
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... located in the cement between the fibers consisting of calcium phosphate [85%]; Calcium carbonate [10%] ; others [5%] which give it the hardness and rigidity. Other than providing the rigid infrastructure, it protects vital organs like the brain], serves as a complex lever system, acts as a storage area for calcium which is vital for human metabolism, houses the bone marrow within its mid cavity and to top it all it is capable of changing its architecture and mass in response to outside and inner stress. It is this dynamic remodeling of bone which is of primary interest in microgravity. To feel the impact of this dynamicity it should be noted that a bone re ...
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... smog, which is a common form of . Fuel combustion for heating and cooling homes,offices,buildings, and factories contribute significantly to . Electric power plants that burn coal or oil in also releases pollutants into the atmosphere. The major pollutants from these source are nitrogen- oxides, sulfur-oxides, and carbon dioxide. The rapid growth of population and industry, and the increased use of automobiles and airplanes has made a very serious and complicated problem. The air we know today and breathe has become so filled with pollutants that it can cause little health problems to fatal health problems such as lung cancer. Polluted air also harms m ...
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... 6- 7). Portland cement is produced by pulverizing clinker consisting essentially of hydraulic calcium silicates along with some calcium aluminates and calcium aluminoferrites and usually containing one or more forms of calcium sulfate (gypsum) as an interground addition. Materials used in the manufacture of portland cement must contain appropriate proportions of calcium oxide, silica, alumina, and iron oxide components. During manufacture, analyses of all materials are made frequently to ensure a uniformly high quality cement. Selected raw materials are crushed, milled, and proportioned in such a way that the resulting mixture has the desired che ...
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... The more bits a TV can transmit, the better the picture or screen resolution. The digital TV signal can carry as many as 19.4 megabits of data, which means a broadcaster can mix multiple programs of varying bit sizes onto a single channel. Say you’re watching a football game, since one camera view only uses up so many bits, you can select a different camera angle while watching the same game on the same channel. It is possible for a network, like NBC, to show two different programs at the same time on the same channel. Conceivably, if the president in on, you can watch regular scheduled programming. With the introduction of the digital TV, the introduc ...
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... the reaction when the magnesium hits the acid when dropped in, it fisses and then disappears giving of hydrogen as it fisses and it leaves behind a solution of hydrogen chloride. The activation energy of a particle is increased with heat. The particles which have to have the activation energy are those particles which are moving, in the case of magnesium and hydrochloric acid, it is the hydrochloric acid particles which have to have the activation energy because they are the ones that are moving and bombarding the magnesium particles to produce magnesium chloride. The rate at which all reactions happen are different. An example of a fast reaction is an explos ...
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... every major continent of the earth. The following wolves are types of Gray Wolves (Canis lupus). In eastern Europe the European Wolf (Canis lupus lupus) can be found even though it used to roam most of western Europe as well. In Spain, two wolves have also been identified-Canis lupus deitanus and Canis lupus signatus. While the first is similar to many of the other European wolves, the latter may be more closely related to the jackal (Canis aureus), than to a wolf. The Caucasion Wolf (Canis lupus cubanensis) is found in many parts of eastern Europe and western Asia. The large tundra wolf of eastern Asia, the Tundra or Turukhan Wolf (Canis lupus albus), is ve ...
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... cells from a female sheep cloned it. The process is very technical and I don’t fully understand it myself. From what I have researched I have come to understand that currently is very “Hit or Miss”(Hawley). From 277 attempts, Dolly was the only successful attempt. The point is however that we now have a man created sheep, what else could be done in the near future. There are many different goals for genetic . Would you like to clone someone close to you who had died? In the movie “Gattaca” you get a peak at something that could be made possible by , the genetic engineering of children not yet born. It could be the end of birth defects. If given the choice to b ...
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... date palm. The writers of this article however have been testing halophytes, which, is a salt-tolerant plant that can be used for food, forage and oilseed crops. They first gathered several hundred halophytes and began testing these plants in the desert of Puerto Peñasco. They irrigated the plants daily by flooding the fields with seawater from the Gulf of California. The best halophytes produced roughly the yield of alfalfa using freshwater irrigation. In order to show that these halophytes could replace other crops for use they tested to see if the crops could feed livestock. The halophytes have protein and carbohydrates but they contain too much salt. This ...
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