Science & TechnologyS


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Cell Growth Regulates Genetic Circuits


Medical Health Today
Tue, 02 Feb 2010 02:00 UTC
Max Planck researchers discover an explanation for different growth rates of genetically identically cells

Genetic circuits control the activity of genes and thereby the function of cells and organisms. Scientists from the Max Planck Institute of Colloids and Interfaces in Potsdam and the University of California at San Diego have shown how various genetic circuits in bacterial cells are influenced by growth conditions. According to their findings, even genes that are not regulated can display different activities - depending on whether they are translated into proteins in slow or fast growing cells. The results provide researchers with new insights into gene regulation and will help them in the design of synthetic genetic circuits in the future (Cell 139, 1366-1375, 2009)

Control circuits do not only exist in CD players, coffee makers, or cars, but also in living cells in this case as "genetic circuits". They consist of a network of different genes which can mutually stimulate or inhibit each other. With the help of these circuits, a cell can switch genes on or off and thus control what proteins it produces.
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Hunger for Stimulation Driven by Dopamine in the Brain According to New Brain Research

Sandra Szivos
Medical Health Today
Tue, 02 Feb 2010 02:00 UTC
Our need for stimulation and dopamine's action upon the brain are connected, which explains why people who constantly crave stimulation are in danger of addictive behaviour such as drug abuse and gambling.

The urge to actively seek out new experiences is a personality trait that psychologists have known about for years, but up until now scientists have been unable to prove how this urge relates to hormonal activities in the brain.

Now, an international research team made up of scientists from the University of Copenhagen, University of Aarhus and University of Tokyo have been able to prove for the first time that this hunger for stimulation is greater on average among people who possess more of the gratification hormone - dopamine in the brain.
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Skin Cells Transformed Directly into Neurons

Tina Hesman Saey
Science News
Mon, 01 Feb 2010 00:00 UTC
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© Thomas Vierbuchen, M. WernigThese neurons were made directly from mouse fibroblasts infected with a three-gene cocktail.
Researchers sidestep conversion to an embryonic state

One small step for skin cells could mean one big leap for regenerative medicine. For the first time, scientists have converted adult cells directly into neurons.

If the technique, performed on mouse cells, works for human cells, the achievement may bypass the need to revert a patient's cells to an embryonic state before producing the type of cell needed to repair damage due to disease or injury.

Researchers at Stanford University transformed skin fibroblast cells from mice into working neurons by inserting genes that encode transcription factors. Transcription factors are proteins that help regulate gene activity, usually by turning genes on. To convert skin cells into neurons, only three genes for regulatory proteins needed to be added, the team reported online January 27 in Nature. The three transcription factors, called Ascl1, Brn2 and Myt1l, normally appear while new neurons are being born.
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Stratospheric Water Vapor Is a Global Warming Wild Card


ScienceDaily
Mon, 01 Feb 2010 22:21 UTC
Stratospheric
© ScienceDailyWater vapor and radiative processes. (Credit: Image courtesy of National Oceanic and Atmospheric Administration)
A 10 percent drop in water vapor ten miles above Earth's surface has had a big impact on global warming, say researchers in a study published online January 28 in the journal Science. The findings might help explain why global surface temperatures have not risen as fast in the last ten years as they did in the 1980s and 1990s.

Observations from satellites and balloons show that stratospheric water vapor has had its ups and downs lately, increasing in the 1980s and 1990s, and then dropping after 2000. The authors show that these changes occurred precisely in a narrow altitude region of the stratosphere where they would have the biggest effects on climate.

Water vapor is a highly variable gas and has long been recognized as an important player in the cocktail of greenhouse gases -- carbon dioxide, methane, halocarbons, nitrous oxide, and others -- that affect climate.
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DNA Testing on 2,000-year-old bones in Italy reveal East Asian Ancestry


Physorg.com
Mon, 01 Feb 2010 22:13 UTC
Researchers excavating an ancient Roman cemetery made a surprising discovery when they extracted ancient mitochondrial DNA (mtDNA) from one of the skeletons buried at the site: the 2,000-year-old bones revealed a maternal East Asian ancestry.

The results will be presented at the Roman Archeology Conference at Oxford, England, in March, and published in the Journal of Roman Archaeology.

According to Tracy Prowse, assistant professor of Anthropology, and the lead author on the study, the isotopic evidence indicates that about 20% of the sample analyzed to-date was not born in the area around Vagnari. The mtDNA is another line of evidence that indicates at least one individual was of East Asian descent.

"These preliminary isotopic and mtDNA data provide tantalizing evidence that some of the people who lived and died at Vagnari were foreigners, and that they may have come to Vagnari from beyond the borders of the Roman Empire," says Prowse. "This research addresses broader issues relating to globalization, human mobility, identity, and diversity in Roman Italy."
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Airports Could Get Mind-Reading Scanners

Bill Christensen
Technovelgy.com
Mon, 01 Feb 2010 19:57 UTC
WeCU Technologies is building a mind-reading scanner that can tell if a given traveler is a potential danger - without the subject's knowledge. WeCU Technologies (pronounced "we see you") is creating a system that would essentially turn the public spaces in airports into vast screening grounds:.

"The system ... projects images onto airport screens, such as symbols associated with a certain terrorist group or some other image only a would-be terrorist would recognize, company CEO Ehud Givon said.

"The logic is that people can't help reacting, even if only subtly, to familiar images that suddenly appear in unfamiliar places. If you strolled through an airport and saw a picture of your mother, Givon explained, you couldn't help but respond.
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Telescope

Fears of Cataclysm Prompt More Research into Asteroids

Stuart Tiffen
Reuters
Mon, 01 Feb 2010 19:44 UTC
Asteroid Impact
© Deutsche WelleAn artists depiction of an asteroid impacting the Earth.
It is only fitting that, in the 21st century, science will occasionally resemble science fiction. So it comes as no surprise that space agencies are building ships to prevent the end of the World.

There is a growing consensus among the global scientific community that the planet is under threat. The danger they warn of is by no means a new one; in fact it is the same one that many hypothesize led to the extinction of the dinosaurs approximately 65 million years ago - asteroids.

Every year more of these clusters of metal, ice, and rock hurtling through space are observed by astronomers. From its operations center in Darmstadt, the European Space Agency (ESA) is deeply involved in researching asteroids and has been cooking up a cosmic caper to pay one a visit for the better part of a decade. But why all the fuss?

According to US space agency NASA, the Solar System is host to more than one million of these so-called Near Earth Objects (NEOs), a term that includes comets and asteroids, that are greater than 40 meters in diameter, considered the threshold size for them to penetrate the Earth's atmosphere. NASA is also tracking more than 1,100 asteroids at least two kilometers in diameter.
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Scientists map changes in science and beyond

Jen Laloup
Public Library of Science
Mon, 01 Feb 2010 19:48 UTC
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© PLoS ONEThis set of scientific fields show the major shifts in the last decade of science. Each significance clustering for the citation networks in years 2001, 2003, 2005 and 2007 occupies a column in the diagram and is horizontally connected to preceding and succeeding significance clusterings by stream fields. Each block in a column represents a field and the height of the block reflects citation flow through the field. The fields are ordered from bottom to top by their size with mutually nonsignificant fields placed together and separated by half the standard spacing. We use a darker color to indicate the significant subset of each cluster. All journals that are clustered in the field of neuroscience in year 2007 are colored to highlight the fusion and formation of neuroscience.
How has the structure of scientific research changed over the past decade? A team of researchers from Umeå University, Sweden, and the University of Washington, USA, aims to answer this question and others in a study published on January 27th in the online, open-access journal PLoS ONE.

Using new mathematical tools, the authors have revealed major shifts in the structure of scientific research in order to uncover structural changes in large, interconnected systems. To illustrate the power of their methods, the researchers mapped changes in the field of neuroscience and were able to track how the field evolved from an interdisciplinary specialty to a full fledged scholarly discipline.
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Tobacco plant-made therapeutic thwarts West Nile virus

Joe Caspermeyer
Arizona State University
Mon, 01 Feb 2010 19:41 UTC
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© Barb Backes, Biodesign Institute at ASUQiang "Shawn" Chen and lead author Huafang "Lily" Lai arrested West Nile virus infection with a new therapeutic manufactured from tobacco plants.
A new therapeutic made from tobacco plants has been shown to arrest West Nile virus infection, according to a new study by Arizona State University scientist Qiang Chen and his colleagues.

Chen, a researcher at Arizona State University's Biodesign Institute and professor in the PolyTechnic Campus' College of Technology and Innovation, is the first to demonstrate a plant-derived treatment to successfully combat West Nile virus after exposure and infection. The research appears in this week's issue of the Proceedings of the National Academy of Sciences (advanced online edition).

There are currently no available vaccines against West Nile, nor effective therapeutics for human use, so the current findings are a considerable advancement and may offer the best hope thus far that the West Nile virus infection can be stopped, even several days after viral infection.
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Brain Responses During Anesthesia Mimic Those During Natural Deep Sleep


ScienceDaily
Mon, 01 Feb 2010 00:00 UTC
The brains of people under anesthesia respond to stimuli as they do in the deepest part of sleep -- lending credence to a developing theory of consciousness and suggesting a new method to assess loss of consciousness in conditions such as coma.

Scientists at the University of Wisconsin School of Medicine and Public Health, led by brain researcher Fabio Ferrarelli, reported their findings in this week's edition of the Proceedings of the National Academy of Science.

The group gave the anesthetic midazolam, commonly used at lower doses in "conscious sedation" procedures such as colonoscopies, to volunteers.
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