Franck Delaplace : la biologie synthétique. Impaired executive function may exacerbate impulsiveness. Executive function (EF), frequently associated with the frontal lobes, guides complex behavior such as planning, decision-making, and response control. EF impairment due to alcohol dependence (AD) has been linked to alcohol's toxic effects on the frontal lobes. A study of EF in a group of adult offspring of AD individuals has found that increased impulsiveness and decreased EF may comprise an inherited trait that signifies greater risk for developing AD.
Results will be published in a special online issue of Alcoholism: Clinical & Experimental Research and are currently available at Early View. "Executive functions are requested each time a subject faces a new situation or when habits are not adapted to a particular situation," explained Fabien Gierski, associate professor at the Université de Reims Champagne-Ardenne, as well as corresponding author for the study. How viruses self assemble. A new model of the how the protein coat (capsid) of viruses assembles, published in BioMed Central's open access journal BMC Biophysics, shows that the construction of intermediate structures prior to final capsid production (hierarchical assembly) can be more efficient than constructing the capsid protein by protein (direct assembly). The capsid enveloping a virus is essential for protection and propagation of the viral genome. Many viruses have evolved a self-assembly method which is so successful that the viral capsid can self assemble even when removed from its host cell.
The construction of large protein structures has been observed experimentally but the mechanism behind this is not well understood. Even the 'simple' icosahedral protein coat of the T1 virus requires integration of 60 protein components. Discussing the practical applications of these results, Dr Schwarz commented, "Hierarchical assembly has not been systematically investigated before. Intelligence is in the genes, but where? Most genes thought to be linked to intelligence probably have no bearing on IQ. You can thank your parents for your smarts -- or at least some of them. Psychologists have long known that intelligence, like most other traits, is partly genetic.
But a new study led by psychological scientist Christopher Chabris of Union College reveals the surprising fact that most of the specific genes long thought to be linked to intelligence probably have no bearing on one's IQ. And it may be some time before researchers can identify intelligence's specific genetic roots. Chabris and David Laibson, a Harvard economist, led an international team of researchers that analyzed a dozen genes using large data sets that included both intelligence testing and genetic data. In nearly every case, the researchers found that intelligence could not be linked to the specific genes that were tested.
"In all of our tests we only found one gene that appeared to be associated with intelligence, and it was a very small effect. Sleeping brain behaves as if it's remembering something. UCLA researchers have for the first time measured the activity of a brain region known to be involved in learning, memory and Alzheimer's disease during sleep. They discovered that this region, called the entorhinal cortex, behaves as if it's remembering something, even during anesthesia–induced sleep — a finding that counters conventional theories about sleep-time memory consolidation. The research team simultaneously measured the activity of single neurons from multiple parts of the brain that are involved in memory formation. The technique allowed them to determine which brain region was activating other areas and how that activation was spreading, said the study's senior author, Mayank R. Mehta, a professor of neurophysics in UCLA's departments of neurology, neurobiology, and physics and astronomy.
"The big surprise here is that this kind of persistent activity is happening during sleep, pretty much all the time," Mehta said. New human neurons from adult cells right there in the brain. Researchers have discovered a way to generate new human neurons from another type of adult cell found in our brains. The discovery, reported in the October 5th issue of Cell Stem Cell, a Cell Press publication, is one step toward cell-based therapies for the treatment of neurodegenerative diseases, such as Alzheimer's and Parkinson's.
"This work aims at converting cells that are present throughout the brain but themselves are not nerve cells into neurons," said Benedikt Berninger, now at the Johannes Gutenberg University Mainz. "The ultimate goal we have in mind is that this may one day enable us to induce such conversion within the brain itself and thus provide a novel strategy for repairing the injured or diseased brain. " The cells that made the leap from one identity to another are known as pericytes. "Now, we reason, if we could target these cells and entice them to make nerve cells, we could take advantage of this injury response," Berninger says. The Trouble With String Theory. I can certainly try. Positivism, as I understand it, is the notion that there are only three possible sources of knowledge of the universe - mathematics, logic, and direct observation.
In essence, it is a radical form of empiricism. It goes further to state that to count as an item of meaningful knowledge, a statement must be verifiable and/or falsifiable. Thus, a sentence like "there is a deli located at the intersection of State and Lake streets" can be a meaningful statement of knowledge, subject to its verification or falsification (In Chicago, for instance, it is false). A sentence like "God prefers dice to bowling" is both unverifiable and unfalsifiable. There is nothing that can be said or observed that could prove or disprove it. The Anthropic Principle very roughly (and according to Wikipedia) is that "observations of the physical universe must be compatible with the conscious life that observes it. " Personally, I think this goes too far.
The Trouble With String Theory. Secrets of the first practical artificial leaf. A detailed description of development of the first practical artificial leaf -- a milestone in the drive for sustainable energy that mimics the process, photosynthesis, that green plants use to convert water and sunlight into energy -- appears in the ACS journal Accounts of Chemical Research. The article notes that unlike earlier devices, which used costly ingredients, the new device is made from inexpensive materials and employs low-cost engineering and manufacturing processes. Daniel G. Nocera points out that the artificial leaf responds to the vision of a famous Italian chemist who, in 1912, predicted that scientists one day would uncover the "guarded secret of plants. " The most important of those, Nocera says, is the process that splits water into hydrogen and oxygen.
The artificial leaf has a sunlight collector sandwiched between two films that generate oxygen and hydrogen gas. The author acknowledges support from the National Science Foundation and the Chesonis Family Foundation. 3-D printed airplane takes flight. When University of Virginia engineering students posted a YouTube video last spring of a plastic turbofan engine they had designed and built using 3-D printing technology, they didn’t expect it to lead to anything except some page views.
But executives at The MITRE Corporation, a McLean-based federally funded research and development center with an office in Charlottesville, saw the video and sent an announcement to the School of Engineering and Applied Science that they were looking for two summer interns to work on a new project involving 3-D printing. They just didn’t say what the project was. Only one student responded to the job announcement: Steven Easter, then a third-year mechanical engineering major.
“I was curious about what they had to offer, but I didn’t call them until the day of the application deadline,” Easter said. He got a last-minute interview and brought with him his brother and lab partner, Jonathan Turman, also a third-year mechanical engineering major. Scientists reverse engineer animal brains to create bionic prosthetic eyes. Utilizing neuroscience, gene therapy, and optogenetics, a pair of researchers from Cornell University have created a bionic prosthetic eye that can restore almost-normal vision to animals blinded by destroyed retinas.
We have discussed bionic eyes at length, but for the most part these have been dumb prosthetics — chips that wire themselves into the ganglion cells behind the retina, which are the interface between the retina and optic nerve. These chips receive optical stimuli (via a CMOS sensor, for example), which they transmit as electrical signals to the ganglion cells. These prosthetic eyes can produce a low-resolution grayscale field that the brain can then interpret — which is probably better than being completely blind — but they don’t actually restore sight. The Cornell prosthetic eye however, developed by Sheila Nirenberg and Chethan Pandarinath, is a much closer analog to a real eye. Its construction and implementation is rather complex, so bear with me. Understanding nuclear power, part 1: Whirlwind nuclear physics. This post is the first in a series on nuclear fission power, intended to provide the background knowledge to understand what is at stake in all major aspects of the nuclear power debate — science and engineering, safety and health, economy and environment.
Energy policy may turn out to be by far the most important issue of our time. Given this, it is crucial that policy-makers and an informed public understand the relative costs and benefits of all the power generation methods that are on the table. Unfortunately, discourse about nuclear power in particular is plagued by wild misinformation. This discourse is heavily politicized, thanks in part to the cold war, and is riddled with fallacies arising from ignorance of the relevant science, heavily influenced by fear. This series of posts is meant to try, in some small way, to correct that. I make no bones about the fact that I am pro-nuclear. Live Forever as an Android?! Breakthrough: Researchers can now create an animal entirely from stem cells. Half of your genes go into each gamete, but they're not necessarily complementary halves.
You could end up with two copies of some genes and no copies of others. If that was true, then every child from the same two parents would be the exact same. You'd end up with Charles II of Spain. I'm a little sketchy on this myself but I think you're overlooking a lot of key details here. Not only do gamete cells only contain on half of your genes, it's not even a simple split down the middle. In other words not all sperm and egg cells are the same. So when a sperm and egg is derived your stem cells and then recombined through fertilization, no, it won't necessarily be a clone of you.
For example the baby that results from this could be of the opposite sex or have blue eyes because the brown eye gene that is dominant in you is not carried over to the child. Cucarachas teledirigidas, ciencia con insectos biónicos: clipset. 11/09/2012 por Joaquín Álviz @rayjaken con 5 comentarios Las cucarachas biónicas no son un juguete, sino una nueva ayuda en tareas de rescate... y quién sabe qué más A la mayoría de nosotros, las cucarachas nos parecen unos insectos bastante desagradables. Muchos no dudan en aplastarlas en cuanto las ven, otros simplemente las evitan, pero a nadie se le había ocurrido conectarle un circuito a la cucaracha para controlar sus movimientos, hasta ahora.Y es que investigadores de… la universidad de Carolina del Norte, en Estados Unidos, han hallado el modo de alterar el comportamiento de una cucaracha (concretamente, utilizan la cucaracha silbadora de Madagascar) mediante el uso de pequeños estímulos eléctricos de muy baja intensidad en determinados sensores del insecto.
Así, han conectado una pequeña placa de circuito, ligera y muy barata, a la parte superior de la cucaracha- cyborg . ¿Cómo funciona la cucaracha biónica? En vídeo Esclavizadas, pero cuidadas + info. New human neurons from adult cells right there in the brain. Humanity+ | Technology & the Future. La viande artificielle déjà dans les assiettes - Business.