Posted: 9/8/2015
- A Red Flag for a Neurodegenerative Disease That May Be Transmissible Animal experiments show how a just-discovered prion triggers a rare Parkinson’s-like disease (“Scientists claim to have discovered the first new human prion in almost 50 years. ... The resulting illness in this case is multiple system atrophy (MSA), a neurodegenerative disease similar to Parkinson's. The study, published August 31 in Proceedings of the National Academy of Sciences, adds weight to the idea that many neurodegenerative diseases are caused by prions.”)
- Metasurface Optics for Better Cellphone Cameras and 3-D Displays (“Engineers at the California Institute of Technology have created a metasurface out of tiny pillars of silicon that act as waveguides for light. The way they arrange the pillars allows them to control the phase of light passing through the surface; this ability gives them control over how the light is focused, as well as its polarization, which is important for uses such as liquid crystal displays and 3-D glasses. Metasurfaces are structured planes so thin that they count as being two-dimensional; their periodic designs manipulate light in unusual ways. … The metasurface could provide the optics for an LCD to create a 3-D display viewable from many angles without glasses.What’s more, all of this can be done using the same lithography techniques used to build computer chips, doing away with individual fabrication and manual alignment of components.”)
- The Next Great GMO Debate Deep inside its labs, Monsanto is learning how to modify crops by spraying them with RNA rather than tinkering with their genes. (“The experiment took advantage of a mechanism called RNA interference. It’s a way to temporarily turn off the activity of any gene. In this case, the gene being shut down was one vital to the insect’s survival.”)
- Antimatter 'surfs' to higher energies on a plasma wave (I think, the title is kind of misleading! This is more about the next generation of powerful electron-positron colliders. “A new technique that accelerates positrons much more efficiently than conventional particle accelerators has been unveiled at the SLAC National Accelerator Laboratory in the US. The technology has the potential to make future positron accelerators more powerful yet more compact, and could also be used to boost the maximum collision energy of existing electron/positron colliders. … One such method is "plasma wakefield acceleration", which was first demonstrated in 2007 and involves firing bunches of electrons into a plasma. An initial "drive" bunch repels the free electrons in the plasma, and this creates a charge-density wave. A second, trailing bunch of electrons "surfs" this wave and gains energy very rapidly. In 2014 Sebastien Corde and researchers at the SLAC National Accelerator Laboratory in California, and international colleagues, accelerated electrons through a gradient of 4.4 GeV/m using this method. ”)
- Nanotubes energize laser-accelerated ions (“An international research team has used carbon nanotubes to enhance the efficiency of laser acceleration, bringing table-top sources for carbon-ion therapy a step closer to reality. ”)
- Arizona’s virgin ant queens could shed light on the predictability of evolution (“To cope, the now-isolated [ant] colonies evolved an identical strategy: The queens lost their wings. New research shows that these parallel adaptations could shed light on a longstanding debate on the predictability of evolution. … For example, the expression of a key gene involved in cell differentiation varied in each of the populations. Other genetic changes repeated themselves in each group, presumably because there are a limited number of ways to make wingless queens. For example, four genes involved in wing patterning all had similarly changed patterns of expression. This is the first study in wild populations to show that adaptation to climate change is a “mosaic” of random and predictable genetic changes”)
- 'Decorated' graphene is a superconductor (“Damascelli and co-workers prepared their samples by growing layers of graphene on silicon-carbide substrates, and then very precisely depositing lithium atoms onto the graphene – a process known as "decorating" – in a vacuum at 8 K.
The team then studied the properties of the samples using angle-resolved photoemission spectroscopy, which exploits the photoelectric effect to measure the momentum and kinetic energy of electrons in a solid. ... an effect that they attributed to enhanced electron–phonon coupling. Crucially, they also showed that this greater coupling leads to superconductivity by identifying an energy gap between the material's conducting and non-conducting electrons – which is the energy needed to break Cooper pairs. At 0.9 meV, the measured value of this gap implies a transition temperature of about 5.9 K – as compared with Profeta and colleagues' prediction of up to about 8 K.”) - Wasps drink special nectar to self-medicate (“Wasps can tell when a parasite infiltrates their body, ... they seek out a type of nectar that’s ... a pretty potent antiparasite medicine, says Discover magazine. The collection of compounds responsible for the decline in parasites (including nicotine) can cut the infection by 50%”)
- Physicists claim 'loophole-free' Bell-violation experiment (“The first "loophole-free" measurement of the violation of Bell's inequality by a quantum system has been claimed by physicists in the Netherlands, Spain and the UK. Their experiment involves entangling spins in diamonds separated by 1.28 km and then measuring correlations between the spins. … In this latest work, Ronald Hanson and colleagues at the Delft University of Technology, along with researchers at the Institute of Photonic Sciences in Barcelona and the diamond-maker Element Six in Oxford, have eliminated what they consider to be the two most significant loopholes that can arise in Bell-violation experiments. Crucially, they have done so simultaneously in one experiment, which had not been done before.”)
- Scientists Uncover Surprising Mechanism Behind Antibiotic-Resistant Bacteria (“Now, scientists at TSRI have discovered that the important human pathogen Staphylococcus aureus, develops resistance to this drug by “switching on” a previously uncharacterized set of genes. Using DNA sequencing technology, the researchers identified a group of genes that work together to fill in for SPase.
They found that, in the absence of SPase, a protein called AyrR switches these genes on to produce proteins called AyrA and AyrBC, which can also cleave off the peptide postal-code sequences.”) - Study by TSRI and Janssen Makes Major Advance Toward More Effective, Long-Lasting Flu Vaccine (“... found a way to induce antibodies to fight a wide range of influenza subtypes—work that could one day eliminate the need for repeated seasonal flu shots. … Researchers zeroed in on a possible target: a protein on the surface of influenza, called hemagglutinin (HA). HA is present on all subtypes of influenza, providing the key viral “machinery” that enables the virus to enter cells. Most importantly, the long “stem” region of HA, which connects the virus to cells, plays such a crucial role that mutations at the site are unlikely to be passed on.”)
- Ants have group-level personalities, study shows (“To determine how group behavior might vary between ant colonies, a team of researchers led by Raphaël Boulay, an entomologist at the University of Tours in France, tested the insects in a controlled laboratory environment. They collected 27 colonies of the funnel ant (Aphaenogaster senilis) and had queens rear new workers in the lab. …
The researchers then observed how each colony foraged for food and explored new environments. They counted the number of ants foraging, exploring, or hiding during set periods of time, and then compared the numbers to measure the boldness, adventurousness, and foraging efforts of each group. They also measured risk tolerance by gradually increasing the temperature of the ants’ foraging area from 26°C to 60°C. …
When they reviewed their data, the scientists found strong personality differences between colonies, they reported online this month in Behavioral Ecology. Some were bold, adventurous risk-takers with highly active foragers. Others were shy, risk-averse, and fearful of new environments. ”) - Massive volcanoes began erupting hundreds of thousands of years before Earth’s largest extinction (“Now, researchers have solved the mystery—using radioactive dating techniques to determine the ages of hundreds of uranium-bearing crystals taken from ancient volcanic rocks collected from sites scattered across a 2.5-million-square-kilometer region of central Russia. Some crystals came from material that had explosively erupted from Earth’s surface and then accumulated in layers hundreds of meters thick ... The earliest phases of the volcanism began about 300,000 years before the onset of the end-of-Permian extinctions, ... All told, an estimated 4 million cubic kilometers of molten material emanated from Siberian peaks and fissures over the course of about 800,000 years, with about two-thirds of that spilling forth before and during the mass extinction. ”)
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