17-10-2007   -   Biology

Wed, 17 Oct 2007 06:00:00 GMT Scientists have found that the f and m type plant thioredoxins previously thought to be localized only in chloroplasts are found in other, nonphotosynthetic, tissues, where they may have multiple functions. They have now established the presence of these redox proteins in tissues other than the chloroplast.more

  11-10-2007   -   Chemistry

Wed 10 Oct 2007 11:00:00 GMT The Nobel Prize in Chemistry for 2007 was awarded to Gerhard Ertl from Fritz-Haber-Institut der Max-Planck-Gesellschaft Berlin, Germany for his studies of chemical processes on solid surfaces.more

  10-10-2007   -   Physics

Tue 09 Oct 2007 11:00:00 GMT The Nobel Prize in Physics for 2007 was awarded jointly to Albert Fert, Université Paris-Sud; Unité Mixte de Physique CNRS Orsay, France and Peter Grünberg, Forschungszentrum Jülich, Germany for the discovery of Giant Magnetoresistance.more

  10-10-2007   -   Chemistry

Tue, 09 Oct 2007 00:00:00 GMT Chemists have synthesized a polyoxometalate with 100 Tungsten and 20 Cerium atoms that has a molar mass of about 30 kilo Dalton. With a maximum diameter of 4.2 nm the inorganic molecule is comparable in size to large complex bio-molecules or even small viruses. Polyoxometalates are anionic metal-oxygen clusters of large structural diversity with chemical properties, which make them especially interesting for applications in catalysis, but also in materials science and nanotechnology. more

  09-10-2007   -   Medicine

Mon, 08 Oct 2007 21:00:00 GMT The Nobel Prize in Physiology or Medicine for 2007 was awarded jointly to Mario R. Capecchi, Martin J. Evans and Oliver Smithies for their discoveries of "principles for introducing specific gene modifications in mice by the use of embryonic stem cells." This year's Nobel Laureates have made a series of ground-breaking discoveries concerning embryonic stem cells and DNA recombination in mammals. Their discoveries led to the creation of an immensely powerful technology referred to as gene targeting in mice. It is now being applied to virtually all areas of biomedicine -- from basic research to the development of new therapies. more

  02-10-2007   -   Agriculture

Insects can catch more than a cold from certain viruses. Some viruses can be lethal to pest species - turning their insides to soup - without harming beneficial insects or other organisms. Hence they are used as an environmentally friendly means of biological crop protection worldwide. The proverbial worm in the apple, the codling moth caterpillar, has been controlled in European orchards for years. But in southwest Germany, some organic apple growers noticed that the virus was losing its effectiveness. Pest resistance to chemical insecticides is common in agriculture, but resistance to viruses had never been a problem in the past. Scientists have now discovered how the codling moth rapidly developed virus resistance.more

  02-10-2007   -   Chemistry

Mon, 01 Oct 2007 21:00:00 GMT When melting sodium at high pressures, the material goes through a transition in which its electrical conductivity drops threefold. Usually when a solid melts, its volume increases. In addition, when pressure is increased, it becomes increasingly difficult to melt a material. However, sodium tells a different story. As pressure is increased, liquid sodium initially evolves into a more compact local structure.more

  02-10-2007   -   Biology

Tue, 02 Oct 2007 06:00:00 GMT While past studies have shown that some microRNAs cause normal cells to divide rapidly and form tumors, this one offers proof that a microRNA can also cause tumors to metastasize. It establishes an important new role for a class of RNA molecules whose significance was discovered only recently. more

  02-10-2007   -   Space

Mon, 01 Oct 2007 00:00:00 GMT A NASA satellite has captured the first images of a collision between a comet and a solar hurricane. It is the first time scientists have witnessed such an event on another cosmic body. more

  15-07-2007   -   ÇäÍáÇáíÉ ÇáåíÏÑæÌíä Ýí ÇáÍ

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