Thursday, July 26, 2007
Tuesday, July 24, 2007
Monday, July 23, 2007
1) The moons that orbit Saturn vary in size, forms, age and origin. Some exhibit rocky, porous or ice surfaces. Others have crater, valleys and a few :tectonic activity. Carl Murray (Queen Mary, University of London: QMUL), a Cassini Imaging Professor, says that it is posible find more moons compose of ice and rocks.
2) Placing mirrors in the surfaces of certain moons, would be possible to set to Saturn always by day.
3) Excepting Titan (the saturnian but great moon, atmosphere with NH3 and methane, able to lodge life and Enceladus: possessing of geysers with water), some small moons like: Franz, Mimas, Hyperion, Pallene, Methone, Polydepsus, Svadi, Erriapo, Narva, Ymir, Yjiraq, etc., could be transported to other places, equipping them with mirrors, turning Earth always by day. Although one does not know if this kind of transfer can cause severe energetic changes in our Solar System.
4) To be used like perennial Saturn’s observatories and trasmissors of data.
5) With installed reflectors of solar light in these moons -directed towards the ring of ice and rocks of Saturn- the planet could work like a gigantic space light.
Sunday, July 22, 2007
Friday, July 20, 2007
Thursday, July 19, 2007
Monday, July 16, 2007
Saturday, July 14, 2007
Thursday, July 12, 2007
George Daley, a scientist of Harvard Stem Cell Institute, said that these, are variants of embryonic stem cells coming from something different to a normal embryo. Not yet we know if these cells, will be as good as those coming from fertilized mature embryos. It exists the possibility that father's lack will deteriorate the performance of these new stem cells. The DNA of the sperm carries particular markers that differ from those carried out in an oocyte’s DNA, being affected the activity of specific genes. For Ronald M. Green, ethicist of Dartmouth College, the processes are ethically acceptable, as long as a human being are not developed and embryos are not destroyed. Nevertheless, the opposition centers their critics against any type of embryonic stem cells producer of specialized tissues, because the process always finishes generating and destroying embryos. The reverend Tad Pacholczyk, of the National Catholic Bioethics Center in Philadelphia, says: if these organized cells growths forming embryos (in the first days and then they stop), they are always human of short life, therefore these embryos should not be created for then to be destroyed.
Wednesday, July 11, 2007
Sunday, July 08, 2007
One understand then that the percentage of fertile ova is extremely low and that an alternating form, of reproducing zebroids exist : clonation (Already achieved in mules, like part of the Project Idaho/2003). If in one of the few fertile ovulatións the zebroid is covered by a horse, a pony will be born and if she is covered by a male zebra a zebra he will be born. Cases are not known in that a zebroid gave birth to a hybrid one similar to her. And, when the zebroid gestates, it is difficult that she take to term the gestation, being born a weak and feeble breeding, in general. Some believe that in these cases, the product, is born with reduced telómeres condition of premature aging. The case remembers to male Rama (crossing of camel sperm with llama ova), gestated after 1 year, by means of assisted fertilization. Llama shows mixed characteristics : llama body and camel face, lack hump and he doesn't spit. The parents of Rama are a female llama of 75 kilos and a male camel of 450. The other case corresponds to the mules (hybrid sterile resultants of crossing a mare : female horse with male donkeys) and to burdéganos (male horse with female ass).
Saturday, July 07, 2007
IV) The fourth criticism to modern synthesis (or, NeoDarwinism), happens from the fact that this primarily deals with the transmission of genes from a generation to another, but not of as how the genes produce the bodies. Recent advances in evolutionary Biology development (evo-devo: comparison of the development of different organisms in order to determine its phylogenétic relations), has shown that gene Pax-6 controls the formation of eyes in mice and humans, the gene Nkx2.5, the heart formation and a set of other genes the formation of the nervous system, providing a weapon to investigate the genetics and development mechanisms that influence the evolution of the forms. A barren problem in this area is the knowledge that different morphologic newness that we observed in clades are not always reflected in the genome. Some biologists argue that this could be explained by genetic duplication (fixation of a cellular or biochemical function in a locus, so that duplicated locus be free to perform a new function) or, by changes in genetic regulation (resulting of interaction and rate of activity of genetic networks, with properties different from the operation of individual genes of the network). Of some way, the discovery of the Homeobox genes allowed to evaluate previous things. Changes in the genetic cis-regulatory systems, would be more significant than changes in the number of genes or the function of proteins (Sean B.Carroll, 2000). The evo-devo theory, maintains that combinatory nature of the regulation of the genetic transcription provides a rich substrate for morphologic diversity, in as much the variations in these level, pattern or rate of genetic expression can provide more variation when natural selection acts on them. Ephigenétics changes include modification of genetic material due to reversible methilatión and other chemical alterations (Eva Jablonka and Marion Lamb, 1995), as well as nonprogrammed remodelling of organism by environmental causes, are due to inherent phenotypic plasticity of developing organisms (Mary Jean West-Eberhard,2003). For some authors, the origin of evo-devo as a consolidated disciplines has to do with Biology transformation undergone by developments made in molecular Biology. Also it has contributed the discovery of unexpected similarities in the genetic regulation of phylogenetically related species of which few genetic regulators are implied in the embriológic foundation of all corporal plans (M. Akam, 1989; Holland, 1992, Holland et. al, 1996).
Thursday, July 05, 2007
Besides it, the NYTimes takes 55 seconds in appearing, Amazon.com: 100 seconds and Yahoo, 2 minutes.
Wednesday, July 04, 2007
The consortium postulates but well that genes interact closely among them, by means of complex nets. That is to say, although somebody has genes inclined to diabetes development, he could not develop the illness if the full genome is influenced by other factors (environmental, dietary or other), cancelers of deleterious effects of these illnesses. These concepts are important because much of current biotechnology works on the base of 1 gene/1 function. Since 1960 it is accepted that a gene that produce a protein type, will produce a quasi similar protein in another organism. This way, the industry has created, patented and defined the industrial gene, like one “that sells and is effective”, says Jack Heinemann, professor of Biological Sciences at the University of Canterbury in New Zealand. In USA, the Patent and Trademark Office allows that new genes be patented on the base of this definition : “orderly sequence of DNA that codes a specific functional product". If each gene is functionally independent -self-questioned the article’s author : could it be a dispute object when somebody implies it for collateral damage, because gene net’s effect?. The processes of genetic engineering and patents that are defined in terms of genes that act in an independent way, begin to be questioned.
Tuesday, July 03, 2007
Sunday, July 01, 2007
Until recently it was laid down that the origin of the agriculture took place in fertile areas of the Middle East (10 000 years B.C.). Nevertheless, the archaeobotánists: D. Piperno and Deborah Pearsall, sustained during years, the existence of crops of domesticated plants of Manihot esculenta (yuca, caloric, carbohydrates, faulty in essential amino acids) and Ipomoea batatas (yam, caloric), in areas tropical Latin Americans areas, by means of the presence of phytolites (conglomerates of vegetable cells that incorporating silica of the surrounding humid earth, acquired special conformations), of wild plants like : Cucúrbita moschata (10 000 years B.C. vitamin A, fatty, caloric), in tropical areas of Ecuador, C. pepo, in Mexico and Zea mays (carbohydrates, small quantities of proteins, and fatty, faulty in essential AA), in Panama (7700 years B.C.. Now Tom Dillehay and collaborators of the University of Vanderbilt, have confirmed the above-mentioned, showing the presence of seeds of C. moschata (pumpkins, rich in vitamin A), domesticated, peanuts skins (Arachis sp, rich in vitamin C and other) and cotton fibers (Gossypium barbadense, industrial textile fiber), in the western hillsides of the valley of Ñanchoc (northern Peru), with data of 10 000, 8500 and 6000 years B.C., respectively, demonstrating that the the development of agriculture in Latin America occurred so early as in the Middle East.
3 articles appeared last week in Science, are possible candidates to scientific breaktroughs of the year. 1) the first one (already, commented by us), is the genomic bacterial transplants, carried out by C. Venter and colleagues 2) total eradication of the HIV-1, virus and its genotype in the laboratory, by means of biological scissors (we comment it today) and a but deep article that we will comment tomorrow :3) related with what is given in calling EVO-DEVO (questions to natural selection`s postulates and organic evolution, settled down by Darwin).
Up to now the therapies to combat the virus of the AIDS don't achieved their final goals (total eradication and/or death of the virus). For that reason when - for some reason - the medication is interrupted (that is of for life), the illness reappears. Some scientists even speak of failure to eradicate this viral epidemic. We believe that the total cure of the AIDS should be based on immunologic mechanisms (vaccination) or others, inside them a more appropriate study of certain affected people (African prostitutes, previously sick) – self-cured - without medications of for half. The paraphernalia of current medications try to impede: a) the union of the virus to the cellular membrane b) the generation of double viral chains (with antiretrovirals), annulling the action of the enzyme reverse transcriptasa c) putting obstacles to the action of the integrase enzyme impeding the entrance of the virus to the cellular nucleus or: d) annulling the action of cellular proteases (that normally conducts protein proteolysis by hydrolysis of the peptide bonds that link amino acids together in the polypeptide chain), an then the adequate shaping of the virus, etc. That´s to say the drugs alone achieve palliative goals. The illness is stopped, but not eliminated. Inside the new therapies against the virus, we find interesting to mention the work of German researchers (Hamburg AIDS, Heinrich-Pette-Institute for Experimental Virology and Immunology and Dresden Max-Planck-Institut for Molecular Cell Biology and Genetics), who have eradicated (killed the HIV-1 integrated provirus and its genotype in the laboratory, in hardly 10 weeks). For it, during 2 years they modified (created an evolved variant), of the enzyme recombinase (usually in charge of to recognize and to cut accurately certain areas of the human normal genotype :DNA). After 129 improved generations of the enzyme recombinase, they were able to obtain a tailored recombinase, the same that after recognizing an asymmetric sequence within the HIV-1 LTR, slowly went eliminating it in cellular cultures, disappearing it with it genotype, until finally to expel virus´remains of affected cells (limphocytes). Nevertheless, Hauber is conscious that his recombinase could also cause damage to normal DNA. For that reason, he says that after 3 years of experiments with animals, they will be clever to begin the clinical tests.