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August 4, 2011, 8:18 AM CT

Nanotechology's impact on mass spectrometry

Nanotechology's impact on mass spectrometry
Genetic Engineering & Biotechnology News (GEN) has retained its position as the number one biotech publisher around the globe since its launch in 1981. For more information, please visit www.genengnews.com

Credit: ©2011, Mary Ann Liebert, Inc., publishers

A move toward smaller and smaller sample sizes is leading to a new generation of mass spectrometry instrumentation, reports Genetic Engineering & Biotechnology News (GEN). From a specific application point of view, novel nanoflow separation methodologies are ramping up the speed and precision with which researchers are able to validate biomarkers, as per the recent issue of GEN (www.genengnews.com/gen-articles/nanoliter-volumes-push-ms-to-new-lows/3741).

"Basing biomarker validation on more sophisticated mass spec tools could help increase the number of clinical applications for biomarkers," said John Sterling, Editor in Chief of GEN.

Proteome Sciences, for example, performs protein biomarker discovery, validation, and mass spec-based assay development and has introduced commercial assays for Alzheimer's disease. In collaboration with Thermo Fisher Scientific, the company has developed isobaric tagging technology in Tandem Mass Tags that allows users to assay up to six samples per run on the Thermo Orbitrap Velos mass spectrometry system.

Scientists at the University of North Carolina in Chapel Hill have developed an integrated microfluidic capillary electrophoresis-MS method using data-independent multiplexed fragmentation to perform high-throughput proteomics. The technique could be applied to a bottom-up proteomic approach and for characterization of protein-based biotherapeutics.........

Posted by: Beverly      Read more         Source


July 20, 2011, 10:22 PM CT

Seeing the S-curve in everything

Seeing the S-curve in everything
Adrian Bejan of Duke University.

Credit: Duke University Photography

From economic trends, population growth, the spread of cancer, or the adoption of new technology, certain patterns inevitably seem to emerge. A new technology, for example, begins with slow acceptance, followed by explosive growth, only to level off before "hitting the wall".

When plotted on graph, this pattern of growth takes the shape of an "S".

While this S-curve has long been recognized by economists and scientists, a Duke University professor believes that a theory he developed explains the reason for the prevalence of this particular pattern, and thus provides a scientific basis for its appearance throughout nature and the man-made world.

"This phenomenon is so common that it has generated entire fields of research that seem unrelated � the spread of biological populations, chemical reactions, contaminants, languages, information and economic activity," said Adrian Bejan, engineering professor at Duke's Pratt School of Engineering. "We have shown that this pattern can be predicted entirely as a natural flow design".

The concept of flow design, whether it be energy, rivers or human populations, is central to Bejan's theory.

The results of this theory of the S-curve, conducted with collaborator Sylvie Lorente from the University Toulouse, France, were published online in the Journal of Applied Physics The research was supported by the National Science Foundation, the U.S. Air Force Office of Scientific Research and the National Renewable Energy Laboratory.........

Posted by: Beverly      Read more         Source


June 22, 2011, 10:49 PM CT

Water within single-walled carbon nanotube pores

Water within single-walled carbon nanotube pores
This global temperature-diameter (T-D) phase diagram of water inside SWCNTs shows that, depending on the water content, hollow or filled ice will form. On the right, hollow- and filled-ice nanotubes can be calculated at low temperature for SWCNTs with diameters indicated with (a) and (b) in the lower portion of the phase diagram.

Credit: Yutaka Maniwa

Water and ice may not be among the first things that come to mind when you think about single-walled carbon nanotubes (SWCNTs), but a Japan-based research team hoping to get a clearer understanding of the phase behavior of confined water in the cylindrical pores of carbon nanotubes zeroed in on confined water's properties and made some surprising discoveries.

The team, from Tokyo Metropolitan University, Nagoya University, Japan Science and Technology Agency, and National Institute of Advanced Industrial Science and Technology, describes their findings in the American Institute of Physics' Journal of Chemical Physics

Eventhough carbon nanotubes consist of hydrophobic (water repelling) graphene sheets, experimental studies on SWCNTs show that water can indeed be confined in open-ended carbon nanotubes.

This discovery gives us a deeper understanding of the properties of nanoconfined water within the pores of SWCNTs, which is a key to the future of nanoscience. It's anticipated that nanoconfined water within carbon nanotubes can open the door to the development of a variety of nifty new nanothings�nanofiltration systems, molecular nanovalves, molecular water pumps, nanoscale power cells, and even nanoscale ferroelectric devices.

"When materials are confined at the atomic scale they exhibit unusual properties not otherwise observed, due to the so-called 'nanoconfinement effect.' In geology, for example, nanoconfined water provides the driving force for frost heaves in soil, and also for the swelling of clay minerals," explains Yutaka Maniwa, a professor in the Department of Physics at Tokyo Metropolitan University. "We experimentally studied this type of effect for water using SWCNTs."........

Posted by: Beverly      Read more         Source


June 5, 2011, 9:04 PM CT

Antimatter atoms for over a quarter of an hour

Antimatter atoms for over a quarter of an hour
This is an artistic representation of the ALPHA neutral antimatter trap, suggesting the nature of the ALPHA apparatus as a container for antihydrogen.

Credit: Chukman So, copyright © 2011 Wurtele Research Group. All rights reserved.

The ALPHA Collaboration, an international team of researchers working at CERN in Geneva, Switzerland, has created and stored a total of 309 antihydrogen atoms, some for up to 1,000 seconds (almost 17 minutes), with an indication of much longer storage time as well.

ALPHA announced in November, 2010, that they had succeeded in storing antimatter atoms for the first time ever, having captured 38 atoms of antihydrogen and storing each for a sixth of a second. In the weeks following, ALPHA continued to collect anti-atoms and hold them for longer and longer times.

Researchers at the U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California at Berkeley, including Joel Fajans and Jonathan Wurtele of Berkeley Lab's Accelerator and Fusion Research Division (AFRD), both UC Berkeley physics professors, are members of the ALPHA Collaboration.

Says Fajans, "Perhaps the most important aspect of this result is that after just one second these antihydrogen atoms had surely already decayed to ground state. These were likely the first ground state anti-atoms ever made." Since almost all precision measurements require atoms in the ground state, ALPHA's achievement opens a path to new experiments with antimatter.........

Posted by: Beverly      Read more         Source


March 31, 2011, 7:01 AM CT

Understanding fathering

Understanding fathering
Most research studies that look at parenting focus on mothers. But fathers also exert direct, unique influences on their children, most likely because they engage with their children in different activities and have different styles of interaction than mothers�such as greater encouragement of risk taking and children's independence. Today, there is renewed attention to the role played by fathers, and there's new research on fathers and their influences on children's development.

At a symposium during the Society for Research in Child Development (SRCD) Biennial Meeting, scientists will use different and complementary methodologies to present findings correlation to fathering across a variety of contexts and cultures.

Among the questions that will be addressed:
  • In dual-earner couples, how do mothers' and fathers' time with and care for their infants differ?
  • In rural American communities, how do fathers' interactions with their children uniquely contribute to the cognitive development of girls and boys from high- and low-income families?
  • In Israeli families, how closely coordinated are moment-to-moment interactions between fathers and infants, and how does this father-infant coordination shape children's later capacity to handle positive and negative encounters with best friends in early adolescence?........

    Posted by: Beverly      Read more         Source


March 17, 2011, 11:01 PM CT

Recycling perlite

Recycling perlite
Three methods for recycling perlite were tested by researchers. They found that the "no stir/sift-then-disinfect" method significantly reduced labor input.

Credit: Photo courtesy of Dr. Hanna Y. Hanna

Perlite, a processed volcanic mineral, is widely used as a component of soilless growing mixes. Lightweight, sterile, and easy to use, perlite is popular with greenhouse growers. But because salt and pathogen buildup can occur when perlite is reused, it must be replaced every year or two to minimize the risk of crop failure. The cost of disposing of old material and replacing it with new perlite can be significant and often prohibitive for smaller greenhouse operations. Hanna Y. Hanna, a researcher at Louisiana State University Agricultural Center's Red River Research Station, has developed a new method for recycling perlite that can save tomato growers a significant amount of money without reducing crop yield.

Hanna, who has done extensive prior research on perlite, says that using the same perlite to grow successive crops like tomatoes can be risky; it tends to compact and is subject to salt build-up and pest contamination. "Steam sterilization of used perlite before planting a new crop is recommended to safeguard against pathogen contamination, but this therapy requires the use of expensive steam generators and is not efficient in desalinating the medium", Hanna said.

In a recent issue of HortTechnology, Hanna reported on a new method developed to accelerate the recycling of perlite. The experiments were conducted in a greenhouse over three growing seasons to evaluate three different methods for perlite recycling and their effects on cost, desalination efficiency, and tomato yield.........

Posted by: Beverly      Read more         Source


March 15, 2011, 10:18 PM CT

Protein folding revealed

Protein folding revealed
Biology Professor Judith Frydman and graduate student Nicholai Douglas, who was first author on the paper published in Cell.
Misfold an origami swan and the worst that happens is you wind up with an ugly paper duckling. Misfold one of the vital proteins in your body - each of which must be folded in a particular way to perform its function - and the result can be a debilitating neurodegenerative disease such as Alzheimer's or Huntington's.

There are no cures for such brain-wasting diseases, but now Stanford scientists have taken an important step that may one day aid in developing therapies for them. They have literally popped the lid off one of the microscopic chambers in which a number of of life's most crucial proteins are folded, witnessing a surprising mechanism as the heretofore hidden folding process happened before their eyes.

Virtually all proteins need to be folded, whether in primitive organisms such as bacteria or multicellular creatures such as humans. A number of are guided through the process by molecules called chaperones, of which a specialized subset - chaperonins - folds a number of of the most complex proteins.

Folding in bacteria has been studied in detail, but Judith Frydman, a professor of biology who led the Stanford research, said this is the first time anyone has seen the folding process performed in higher organisms.

"The mechanism of folding we saw in the chaperonin is very different from what we expected and from what has been seen in bacteria," Frydman said. "It was really surprising, and we are still amazed that it worked. This chaperonin appears to provide a unique chemical environment".........

Posted by: Beverly      Read more         Source


March 10, 2011, 7:31 AM CT

The Power to Be Scientists

The Power to Be Scientists
Children who are taught how to think and act like researchers develop a clearer understanding of the subject, a study has shown.

The research project led by The University of Nottingham and The Open University has shown that school children who took the lead in investigating science topics of interest to them gained an understanding of good scientific practice.

The study shows that this method of 'personal inquiry' could be used to help children develop the skills needed to weigh up misinformation in the media, understand the impact of science and technology on everyday life and help them to make better personal decisions on issues including diet, health and their own effect on the environment.

The three-year project involved providing pupils aged 11 to 14 at Hadden Park High School in Bilborough, Nottingham, and Oakgrove School in Milton Keynes with a new computer toolkit named nQuire, now available as a free download for teachers and schools.

Running on both desktop PCs and handheld notebook-style devices, the software is a high-tech twist on the traditional lesson plan - guiding the pupils through devising and planning scientific experiments, collecting and analysing data and discussing the results.

The pupils were given wide themes for their studies but were asked to decide on more specific topics that were of interest to them, including heart rate and fitness, micro climates, healthy eating, sustainability and the effect of noise pollution on birds.........

Posted by: Beverly      Read more         Source


March 1, 2011, 9:17 PM CT

Relaxation leads to lower elasticity

Relaxation leads to lower elasticity
Bended actin/fascin bundles indicate stress, incorporated when the network formed. As relaxations over time gradually diminish these tensions, their contribution to the network's elasticity disappears. (length of the bar: 2 µm)

Credit: Picture: TUM

A number of materials, when observed over a sufficiently long period of time, show changes in their mechanical properties. The exact course of these developments depends on the underlying microscopic mechanisms. However, the microscopic structure and the complexity of the systems make direct observation extremely difficult.

That is why a team led by Professor Andreas Bausch from the Chair of Cellular Biophysics resorted to a model system that can be precisely controlled using actin filaments, a biopolymer that, among other things, is responsible for muscle contractions in the human body. Together with the crosslinking molecule fascin, actin filaments build an interconnected network whose elasticity decreases with increasing age. Deploying a wide-ranging combination of experimental techniques, the scientists have now managed to cast light on the source of these changes.

As the study published in Nature Materials shows, microscopic relaxation processes are the source of the macroscopic changes in the polymer network properties. During the formation of the network internal tensions build up. Because the linking points in the network are not of permanent nature, but rather open and close at random intervals, these tensions gradually diminish. Over a period of ten hours the elasticity drops to about a fifth of the initial value and then remains stable.........

Posted by: Beverly      Read more         Source


February 22, 2011, 7:57 AM CT

Iceland Volcano for High-Grade Energy

Iceland Volcano for High-Grade Energy
Geologists drilling an exploratory geothermal well in 2009 in the Krafla volcano in Iceland met with a big surprise: underground lava, also called magma, flowed into the well at 2.1 kilometers (6,900 feet) depth.

It forced the researchers to stop drilling.

"To the best of our knowledge, only one prior instance has been documented of magma flowing into a geothermal well while drilling," said Wilfred Elders, a geologist at the University of California, Riverside, who led the research team.

The researchers received $3.5 million from the National Science Foundation (NSF), and $1.5 million from the International Continental Scientific Drilling Program, to conduct their research.

Elders and his team studied the well within the Krafla caldera as part of the Iceland Deep Drilling Project, an industry-government consortium, to test whether geothermal fluids at supercritical pressures and temperatures could be exploited as sources of power, said Leonard Johnson, program director in NSF's Division of Earth Sciences, which funded the research.

"We were drilling a well designed to search for very deep--4.5 kilometers (15,000 feet)--geothermal resources in the volcano," said Elders.

"While the magma flow interrupted our project, it gave us a unique opportunity to test a very hot geothermal system as an energy source.".........

Posted by: Beverly      Read more         Source


February 14, 2011, 7:43 AM CT

Electronic Mining of Published Research

Electronic Mining of Published Research
The knowledge of knowledge. The science of science. Riddles? No. A burgeoning and important field of scientific research that examines research itself, say University of Chicago Sociology Assistant Professor James Evans and Post-doctoral Scholar Jacob Foster. Their analysis, supported by the National Science Foundation (NSF), is published in a perspective piece to appear in the Feb. 11 issue of the journal Science

A scientific approach to delving into the knowledge of knowledge--metaknowledge--offers great potential for new discovery, they argue. New possibilities may arise when one uncovers scientific bias, possible "ghost theories" or acquires an understanding of the context of research, and then accounts for those factors or eliminates them and engages in new research.

"We review the expanding scope of metaknowledge research, which uncovers regularities in scientific claims and infers the beliefs, preferences, research tools and strategies behind those regularities. Metaknowledge research also investigates the effect of knowledge context on content. Teams and collaboration networks, institutional prestige and new technologies all shape the substance and direction of research.".

Metaknowledge can be very useful to a variety of disciplines and fields. Evans' and Foster's research, while primarily funded by NSF's Science of Science and Innovation Policy, was co-funded by NSF's Division of Chemistry interested in reviewing developments in Chemistry over time.........

Posted by: Beverly      Read more         Source


February 7, 2011, 11:05 PM CT

Continued Alcohol Abuse leads to brain damage

Continued Alcohol Abuse leads to brain damage
It is not uncommon to have a glass or two of wine with dinner, a smooth cocktail at a party, or a few beers while watching the game. These forms of light drinking typically do not cause radical health issues. Alcohol is a common element to many social gatherings and drinking is an acceptable pastime. That is, until consuming too much alcohol creates a problem. When alcohol becomes a problem and a person’s drinking interferes with their lives, it’s time for alcohol rehab. If an alcoholic refuses alcohol addiction treatment and continues to abuse alcohol, it will lead to brain damage and other series health issues.

Alcohol is a recreational drug that should be used in moderation. When a person continues to consume alcohol in an abusive way, it can lead to brain damage. One of the most common brain disorders found in alcoholics is called Wernicke-Korsakoff Syndrome. There are two stages of this permanent brain disorder, the first is Wernicke. In this first stage, the disease can be cured by living healthy and by discontinuing the use of alcohol. If healthy lifestyle changes do not take place, the syndrome will progress into Karsakoff Syndrome, which is a permanent brain disorder.

The majority of Korsakoff syndrome patients have abused alcohol for 20 to 30 years and have a vitamin B deficiency. People with Karsakoff syndrome have drooping eyelids, exhibit confusion, and suffer from severe long-term and short-term memory loss. When the patient can not remember past events, they begin to make up stories. One of the hardest aspects of this illness is that suffers usually do not know that they are sick. If the person does not stop drinking at this point, they will be hospitalized. ........

Posted by: Beverly      Read more         Source


February 2, 2011, 10:48 PM CT

Synthetic materials that behave like mollusk shells

Synthetic materials that behave like mollusk shells
Nacre, usually known as mother-of-pearl, is the iridescent material lining a number of mollusk shells. It is part of a two-layer armor system that protects the animal from predators. The brittle outer layer of the shell absorbs the initial impact, but is prone to cracking. To prevent these cracks from catastrophically propagating through the shell to the animal itself, the nacreous layer is surprisingly strong and tough, with outstanding crack arresting properties. Thus it acts as a lining to maintain the integrity of the shell in the event of cracking of the outer layer.

"What makes this natural material unique is that it is composed of relatively weak constituents," said Owen Loh, a graduate student at Northwestern University. At the microscale, brittle calcite tablets are stacked in a brick-and-mortar-like structure with thin layers of biopolymer lining the interfaces between tablets. This results in a material that well outperforms its individual constituents. For example, the toughness of nacre is orders of magnitude greater than that of the tablet material itself. In addition, nacre is at once strong and tough, a combination that is generally mutually exclusive in engineering materials.

As a result, nacre has been the object of significant interest within the materials community and serves as a model after which numerous man-made composite materials are designed. This includes composites for light-weight armor systems and structural elements in transportation and aerospace applications.........

Posted by: Beverly      Read more         Source


Sun, 30 Jan 2011 17:07:48 GMT

Mida salicifolia

Mida salicifolia
....and we"re back. Sorry for the gap of a few days, it took us a while to sort out some of the issues in the set-up of the software behind the scenes. I hope it"s all resolved now, and the biggest issue of photographs not loading should finally be fixed.

Claire wrote today"s entry (thanks again, Claire):

A change from flowers for today. Tony Foster (Tonyfoster@Flickr) from Kaeo, New Zealand, provided this photograph (via the BPotD Flickr Pool) of fruit of the small tree, Mida salicifolia. Much appreciated Tony!

A native to the North Island of New Zealand, Mida salicifolia of the Santalaceae is a small tree found in mixed podocarp forests. The Santalaceae contains 44 genera and 990 species and is broadly distributed throughout temperate and tropical regions of the world.

A hemi-parasite like other members of its family, Mida salicifolia parasitizes through its roots, where it steals some nutrients from its host (often the kauri tree, Agathis australis). However, the species is also capable of photosynthesizing and living independently. A well-known example of another hemi-parasitic species in the family is mistletoe.

Maire taiki is the Māori name for Mida salicifolia, but there are several other species of native New Zealand trees bearing the name maire such as maire hau (Leionema nudum)and maire tawake (Syzgium maire). The Māori Dictionary has additional matches for maire. English common names include New Zealand sandalwood and willow-leaved maire.

The leaves of Mida salicifolia are lance-like (salicifolia = "leaves of a willow") and glossy. Its flowers (see photos on link) are quite diminutive in comparison to the size and appearance of the bright red berries (7-12 x 6-8 mm). Often this species is confused at a glance with small trees of Nestegis species (common names also being maire), but can be easily distinguished by looking at the leaf arrangement: Mida salicifolia has alternate leaves while Nestegis spp. have opposite leaves. Additional photographs of the flowers and vegetative parts of Mida salicifolia (and another member of the family, Korthalsella salicornioides can be found on the University of Auckland, Biological Sciences website: Santalaceae.

The New Zealand Plant Conservation Network (also linked above) states that Mida salicifolia is in decline in areas where browsing occurs from introduced mammal species such as goat, possum, and deer. However, it is relatively widespread, and remains particularly abundant on possum-free islands.

Posted by: Daniel Mosquin      Read more     Source


January 28, 2011, 7:15 PM CT

Mathematical Model Predict and Prevent Future Extinctions

Mathematical Model Predict and Prevent Future Extinctions
In an effort to better understand the dynamics of complex networks, researchers have developed a mathematical model to describe interactions within ecological food webs. This research, performed by Northwestern University physics professor Adilson Motter and his student, Sagar Sahasrabudhe, is reported in the January 25 issue of Nature Communications The work illustrates how human intervention may effectively aid species conservation efforts.

"Our study provides a theoretical basis for management efforts that would aim to mitigate extinction cascades in food web networks. There is evidence that a significant fraction of all extinctions are caused not by a primary perturbation but instead by the propagation of a cascade," said Motter.

Extinction cascades are often observed following the loss of a key species within an ecosystem. As the system changes to compensate for the loss, availability of food, territory and other resources to each of the remaining members can fluctuate wildly, creating a boom-or-bust environment that can lead to even more extinctions. As per the study, more than 70 percent of these extinctions are preventable, assuming that the system can be brought into balance using only available resources--no new factors appears to be introduced.........

Posted by: Beverly      Read more         Source


January 21, 2011, 7:45 PM CT

When Students Put Down Textbooks

When Students Put Down Textbooks
Put down those science text books and work at recalling information from memory. That's the shorthand take away message of new research from Purdue University that says practicing memory retrieval boosts science learning far better than elaborate study methods.

"Our view is that learning is not about studying or getting knowledge 'in memory,'" said Purdue psychology professor Jeffrey Karpicke, the lead investigator for the study that appears today in the journal Science "Learning is about retrieving. So it is important to make retrieval practice an integral part of the learning process.".

Educators traditionally rely on learning activities that encourage elaborate study routines and techniques focused on improving the encoding of information into memory. But, when students practice retrieval, they set aside the material they are trying to learn and instead practice calling it to mind.

The study, "Retrieval Practice Produces More Learning Than Elaborative Studying With Concept Mapping," tested both learning strategies alongside each other. The research was funded by the National Science Foundation's Division of Undergraduate Education.

"In previous research, we established that practicing retrieval is a powerful way to improve learning," said Karpicke.  "Here we put retrieval practice to the test by comparing its effectiveness to an elaborative study method, specifically elaborative studying by creating concept maps.".........

Posted by: Beverly      Read more         Source


January 16, 2011, 10:01 PM CT

New class of materials from self-assembling structures

New class of materials from self-assembling structures
Illinois researchers developed tiny spheres that attract in water to form "supermolecule" structures. Pictured from L-R: Qian Chen, Sung Chul Bae, Jonathan Whitmer, Steve Granick.

Credit: L. Brian Stauffer

Scientists at the University of Illinois and Northwestern University have demonstrated bio-inspired structures that self-assemble from simple building blocks: spheres.

The helical "supermolecules" are made of tiny colloid balls instead of atoms or molecules. Similar methods could be used to make new materials with the functionality of complex colloidal molecules. The team will publish its findings in the Jan. 14 issue of the journal Science

"We can now make a whole new class of smart materials, which opens the door to new functionality that we couldn't imagine before," said Steve Granick, Founder Professor of Engineering at the University of Illinois and a professor of materials science and engineering, chemistry, and physics.

Granick's team developed tiny latex spheres, dubbed "Janus spheres," which attract each other in water on one side, but repel each other on the other side. The dual nature is what gives the spheres their ability to form unusual structures, in a similar way to atoms and molecules.

In pure water, the particles disperse completely because their charged sides repel one another. However, when salt is added to the solution, the salt ions soften the repulsion so the spheres can approach sufficiently closely for their hydrophobic ends to attract. The attraction between those ends draws the spheres together into clusters.........

Posted by: Beverly      Read more         Source


Mon, 17 Jan 2011 01:03:40 GMT

Rhodophiala rhodolirion

Rhodophiala rhodolirion
Local plant enthusiast Alan Tracey sent this photograph a few days ago from Chile, taken during his explorations of Andean summer wildflowers. Thanks as always, Alan!

Rhodophiala translates to "red-saucer" or "red-shallow cup" (a reference to the broadly funnel-shaped red flowers) and rhodolirion to "red-" or "rose-lily". The latter name is in reference to the typical pink flower of today"s species, seen in photographs here: añañuca de cordillera.

Native to Chile and Argentina, this taxon is one of thirty or so in the genus, all native to south Andean South America. Members of Rhodophiala have in the past been considered to be part of either Amaryllis (now solely recognized as a South African genus and quite distant phylogenetically within the family) or Hippeastrum. Though closely related, Presl"s interpretation of this group of species as distinct from Hippeastrum is now generally accepted. However, I"ve been so far unable to track down a set of characteristics that justifies this (the width of the leaves is used as a character distinguishing the two genera in this Key to the Hippeastreae, but that would not typically be enough to taxonomically define two distinct groupings, so there must be other differences).

The Pacific Bulb Society Wiki has photographs of a dozen or so taxa and a few cultivated selections (and Rhodophiala phycelloides was previously featured on BPotD). All are similar in habit: lily-like flowers borne on leafless scapes with narrow strap-like leaves emerging from the bulbs.

Posted by: Daniel Mosquin      Read more     Source


January 16, 2011, 10:39 AM CT

Exploring Latest Materials Innovation and Research

Exploring Latest Materials Innovation and Research
How do far-out creations, such as airplanes that change shape in flight, invisibility cloaks or military vehicles that heal themselves, become realities? Via scientific discoveries and generation of new materials, of course.

New and often revolutionary uses for materials are endless, and materials innovations drive civilization and inspire scientific breakthroughs.

It's that notion that motivated the popular science television series NOVA to take viewers on a behind-the-scenes tour of the world of materials.

In a new, four-part NOVA series, Making Stuff: Stronger, Smaller, Cleaner, Smarter, New York Times technology reporter David Pogue travels the globe to examine the latest advancements in materials research and to find out what the future might hold in this field. The series airs on four consecutive Wednesdays, beginning Jan. 19, 2011 at 9 p.m. ET/PT on local PBS stations.

Major funding for Making Stuff is provided by the National Science Foundation's (NSF) Informal Science Education program. NSF's Directorate for Math and Physical Sciences also provides funding through its Division of Materials Research and Office of Multidisciplinary Activities. Additional funding is provided by the Department of Energy. The cloud trend has allowed firms to outsource their email systems to hosted Exchange providers and significantly cut costs.

Posted by: Beverly      Read more         Source


January 11, 2011, 6:22 AM CT

Snapshots of proteins as they fold

Snapshots of proteins as they fold
An unfolded protein is a string made up of amino acids. When the protein folds it forms structures like the alpha helix (the corkscrew) and the beta sheet (the flat ribbon) in the image to the right. These secondary structures then double back on themselves to form the final structure.
Researchers have invented a way to 'watch' proteins fold - in less than thousandths of a second -- into the elaborate twisted shapes that determine their function.

People have only 20,000 to 30,000 genes (the number is hotly contested), but they use those genes to make more than 2 million proteins. It's the protein molecules that domost of the work in the human cell. After all, the word protein comes from the Greek prota, meaning "of primary importance".

Proteins are created as chains of amino acids, and these chains of commonly fold spontaneously into what is called their "native form" in milliseconds or a few seconds.

A protein's function depends sensitively on its shape. For example, enzymes and the molecules they alter are often described as fitting together like a lock and key. By the same token, misfolded proteins are behind some of the most dreaded neurodegenerative diseases, such as Alzheimer's, Parkinson's and mad cow disease.

Researchers can't match the speed with which proteins fold. Predicting how chains of amino acids will fold from scratch requires either powerful supercomputers or cloud sourcing (harnessing the pattern recognition power of thousands of people by means of games such as Folding@home).

Either way, prediction is time-consuming and often inaccurate, so much so that the protein-structure bottleneck is slowing the exploitation of DNA sequence data in medicine and biotechnology.........

Posted by: Beverly      Read more         Source


Mon, 10 Jan 2011 03:31:02 GMT

Euphorbia pulcherrima hybrid

Euphorbia pulcherrima hybrid
Today"s photographs are courtesy of Ana Margarida Silva of Portugal, who sent them along as a season"s greeting to everyone who contributes to Botany Photo of the Day, including readers, commenters, photographers and writers. Claire wrote today"s entry:

For a holiday theme, today"s post will be about the well-known Euphorbia pulcherrima of the spurge family, Euphorbiaceae. The poinsettia! Called Cuetlaxochitl by the Aztecs, the poinsettia is a native to Mexico and Central America and has been used by humans for centuries before 16th century legend linked the species to Christmas. The Aztecs used Euphorbia pulcherrima as a red dye (from the floral bracts) and also medicinally for reducing fever (antipyretic, much like aspirin). The true inflorescence--a cyathium--is small and grows in the centre of the richly-coloured bracts.

Euphorbia pulcherrima has a long history as a Christmas flower before it was brought to North America in the 19th century by Joel Roberts Poinsett, the Mexican ambassador for the United States. In Mexico, the flowers of the species are sometimes called Flores de Noche Buena (Flowers of the Holy Night -- Christmas Eve). The legend behind this name and its symbolism stems from a story about Pepita, a young Mexican girl, who had nothing to offer as a gift for the birthday of Jesus. Pepita was told by an angel to bring roadside weeds to the church, and as she lay her humble gift on the altar, the weeds miraculously bloomed large red flowers.

The poinsettia is a very popular plant commercially during the holidays (almost all are sold within the six weeks before December 25). A near-monopoly on commercial production existed until the early 1990s in the USA due to a production secret. Euphorbia pulcherrima requires a strict light schedule and temperature regime to produce the vividly coloured bracts, but this wasn"t a secret in comparison to how to produce consistent, compact flowering plants. The grafting technique to do this is no longer secret, though, and production has now shifted to parts of the world where labour is less expensive.

If you are worried about poisoning, the tales of toxicity are untrue. Euphorbia pulcherrrima is a mild irritant to the skin and stomach. Copious amounts of leaves ingested would only produce minimal symptoms and discomfort.

Wikipedia has more information on cultivation and images of the many varieties of poinsettia which can come in nearly any color in the wild (except blue or purple) and are cultivated in white, red and pink (though red, unsurprisingly, is the most popular).

Happy holidays!

Posted by: Daniel Mosquin      Read more     Source


January 7, 2011, 7:02 AM CT

Globally Sustainable Fisheries Possible

Globally Sustainable Fisheries Possible
Fishing boats line the beach at Punta del Diablo, a seaside fishing community in Uruguay.
The bulk of the world's fisheries--including the kind of small-scale, often non-industrialized fisheries that millions of people depend on for food--could be sustained using community-based co-management. This is the conclusion of a study reported in this week's issue of the journal Nature.

"The majority of the world's fisheries are not--and never will be--managed by strong centralized governments with top-down rules and the means to enforce them," says Nicolas Gutierrez, a University of Washington fisheries scientist and main author of the Nature paper.

"Our findings show that a number of community-based co-managed fisheries around the world are well managed under limited central government structure, provided communities of fishers are proactively engaged," he says.

"Community-based co-management is the only realistic solution for the majority of the world's fisheries, and is an effective way to sustain aquatic resources and the livelihoods of communities depending on them".

Under such a management system, responsibility for resources is shared between the government and users.

"This important research shows that a better understanding of ecological, social and economic interactions--and shared responsibilities for management--can yield sustainable well-being for ecosystems and fishers alike," says Phillip Taylor, section head in the National Science Foundation (NSF)'s Division of Ocean Sciences, which funded the research.........

Posted by: Beverly      Read more         Source


December 24, 2010, 1:27 PM CT

Heat shock protein drives yeast evolution

Heat shock protein drives yeast evolution
hitehead Institute scientists have determined that heat shock protein 90 (Hsp90) can create diverse heritable traits in brewer's yeast (Saccharomyces cerevisiae) by affecting a large portion of the yeast genome. The finding has led the scientists to conclude that Hsp90 has played a key role in shaping the evolutionary history of the yeast genome, and likely others as well.

RELEVANCE: Over the past several years, Whitehead Member Susan Lindquist has built the case that heat shock proteins (Hsps), which are found across species from bacteria to humans, are responsible for substantial evolutionary changes in relatively short periods of time. The current research reveals how Hsp90 functions across more than 100 brewer's yeast strains to mask or reveal a number of traits simultaneously and instantaneously in response to stressful environments. This sudden unveiling of multiple new phenotypes may also explain the rapid evolution of interdependent traits that on their own might prove detrimental.

CAMBRIDGE, Mass. (December 23, 2010) � Whitehead Institute scientists have determined that heat shock protein 90 (Hsp90) can create heritable traits in brewer's yeast (Saccharomyces cerevisiae) by affecting a large portion of the yeast genome. The finding has led to the conclusion that Hsp90 has played a key role in genome evolution.........

Posted by: Beverly      Read more         Source


December 21, 2010, 6:27 AM CT

Global rivers emit greenhouse gas nitrous oxide

Global rivers emit greenhouse gas nitrous oxide
What goes in must come out, a truism that now appears to be applied to global river networks.

Human-caused nitrogen loading to river networks is a potentially important source of nitrous oxide emission to the atmosphere. Nitrous oxide is a potent greenhouse gas that contributes to climate change and stratospheric ozone destruction.

It happens via a microbial process called denitrification, which converts nitrogen to nitrous oxide and an inert gas called dinitrogen.

When summed across the globe, researchers report this week in the journal Proceedings of the National Academy of Sciences (PNAS), river and stream networks are the source of at least 10 percent of human-caused nitrous oxide emissions to the atmosphere.

That's three times the amount estimated by the Intergovernmental Panel on Climate Change (IPCC).

Rates of nitrous oxide production via denitrification in small streams increase with nitrate concentrations.

"Human activities, including fossil fuel combustion and intensive agriculture, have increased the availability of nitrogen in the environment," says Jake Beaulieu of the University of Notre Dame and the U.S. Environmental Protection Agency in Cincinnati, Ohio, and main author of the PNAS paper.

"Much of this nitrogen is transported into river and stream networks," he says, "where it appears to be converted to nitrous oxide, a potent greenhouse gas, via the activity of microbes".........

Posted by: Beverly      Read more         Source


December 16, 2010, 7:20 AM CT

Federal oversight needed in synthetic biology

Federal oversight needed in synthetic biology
he Presidential Commission for the Study of Bioethical Issues today released its first reporta wide-ranging review of the emerging field of synthetic biologyissuing 18 recommendations including a call for coordinated federal oversight of researchers working in both large institutions and smaller settings.

The panel, comprised of 13 scientists, ethicists, and public policy experts, said that the very newness of the science, which involves the design and construction of laboratory-made biological parts, gives regulators, ethicists and others time to identify any problems early on and craft solutions that can harness the technology for the public good.

"We comprehensively evaluated the developing field of synthetic biology to understand both its potential rewards and risks," said Dr. Amy Gutmann, the Commission Chair and President of the University of Pennsylvania. "We considered an array of approaches to regulationfrom allowing unfettered freedom with minimal oversight and another to prohibiting experiments until they can be ruled completely safe beyond a reasonable doubt. We chose a middle course to maximize public benefits while also safeguarding against risks."

Dr. Gutmann said the Commission's approach recognizes the great potential of synthetic biology, including life saving medicines, and the still distant risks posed by the field. "Prudent vigilance suggests that federal oversight is needed and can be exercised in a way that is consistent with scientific progress," she said.........

Posted by: Beverly      Read more         Source


December 15, 2010, 7:15 AM CT

Elusive neuronal targets of deep brain stimulation

Elusive neuronal targets of deep brain stimulation
Deep brain stimulation of the anterior thalamic nucleus in the mouse brain results in an increase in the number of new neurons due to an increase in cell division in the mouse hippocampus, specifically among neural stem (green) and progenitor cells (pink).

Credit: Grigori Enikolopov@CSHL

hooting steady pulses of electricity through slender electrodes into a brain area that controls complex behaviors has proven to be effective against several therapeutically stubborn neurological and neuropsychiatric disorders. Now, a newly released study has observed that this technique, called deep brain stimulation (DBS), targets the same class of neuronal cells that are known to respond to physical exercise and drugs such as Prozac.

The study, led by Associate Professor Grigori Enikolopov, Ph.D., of Cold Spring Harbor Laboratory (CSHL), is the cover story in the January 1st issue of The Journal of Comparative Neurology, which is currently available online.

The targeted neuronal cells, which increase in number in response to DBS, are a type of precursor cell that ultimately matures into adult neurons in the brain's hippocampus, the control center for spatial and long-term memory, emotion, behavior and other functions that go awry in diseases such as Alzheimer's, Parkinson's, epilepsy and depression. DBS has been successful in treating some cases of Parkinson's. And recently, it has also proven to work against other brain disorders such as epilepsy and severe depression.

"But the clinical application of DBS to treat neuropsychiatric disorders is still problematic because there isn't a clear rationale or a guide for which brain regions need to be stimulated to achieve maximum therapeutic benefit," says Enikolopov. "Our study now points to the brain region whose stimulation results in new cell growth in the hippocampus, an area that is implicated in a number of behavioral and cognitive disorders."........

Posted by: Beverly      Read more         Source


December 10, 2010, 11:41 PM CT

Deals on Electronics, Watches, Family Products

Deals on Electronics, Watches, Family Products
New York (12/10/2010)-For perpetual bargain hunters and other shoppers looking to get a great deal on the latest electronics, brand name watches, wireless accessories, jewelry and more, 1SaleaDay.com is the lowest-priced deal-of-the-day website offering unheard-of exclusive deals on just a single item and only for 24 hours. To keep customers coming back for more, 1SaleaDay.com even offers surprise free products once or twice a week.

As the largest independently-owned daily deal site in the world, 1SaleaDay.com leverages its tremendous buying power with major brands and retailers plus a dedicated team of competitive price-comparison experts to offer outrageous deals to more than 350,000 daily site visitors, like a Magellan Roadmate GPS, HD camcorder or 12 MP digital camera-all of which recently sold for just $39.99.

How 1SaleaDay.com offer such amazing prices? Rather than spend precious dollars on marketing to attract new customers, 1SaleaDay focuses on giving deep savings to customers, who then pass the word on about the great deals they've discovered at the site.

"Thousands of customers make 1SaleaDay.com their first web stop of the day to see what's hot and get the best deal on the products they want at a price anyone can afford," said Ben Federman CEO of 1SaleaDay.com. "Collectors, gadget geeks and even parents and grandparents check us out first to get the best deals anywhere on the web on gifts for their kids or grandkids - or even for themselves".

With a new deal posted everyday at midnight EST in each of five categories-Deal of the Day, Wireless, Watch, Family and Jewelry-1SaleaDay entices shoppers who stop by every day to check out the deal, offering items like a TomTom GPS device, luxury watches, a waterproof MP3 player with earphones, black freshwater cultured pearls, and even kid's games, accessories and home decor.

Once in a while, 1SaleaDay clears out its inventory with the Chunk o'Junk Deal featuring a box full of items randomly selected from past deals, such as laptops, MP3 players, USB adapters, GPS units, cables, accessories and cell phones - a $200 value - sold for just $5 plus $5 shipping. Chunk o'Junk deals are limited to the first 1,000 customers and are commonly gone in just a few hours.

"Customers often tell us that they love shopping at 1SaleaDay not only for the great deals, but also for the fun, creative and catchy descriptions for the products," Federman said. "We don't just tell them about the product-we tell them how they can use it to get the most out of their purchase."

Most items ship the day after ordering and typically arrive in 3-5 business days via UPS or USPS. Products offered on 1SaleaDay.com are almost always new, in original packaging, with occasional deals on refurbished or wholesale packaged items for even greater savings. The site is accredited by the Better Business Bureau, and authenticated secure by Comodo, Authorize.net, McAfee and PayPal.

To find out about today's Deal of the Day, visit www.1SaleaDay.com. And, stop back tomorrow for a different deal-there's a new one posted every day.

About 1SaleaDay.com
1SaleaDay.com offers the deepest discounts on a variety of merchandise with a new deal posted every day at 12 midnight EDT. With Deals of the Day in five categories, including Wireless, Watch, Family and Jewelry, 1SaleaDay leverages its global buying power to offer discounts up to 90% off retail prices for electronics, collectibles, housewares, toys and more. Headquartered in New York, NY, 1SaleaDay.com is part of a family of discount retailers that includes Ben's Outlet, Dynamite Time and Glasses Unlimited. For more information, visit, www.1SaleaDay.com
MEDIA CONTACT:
Belinda Banks.

SS | PR.

609 750 9110.

belinda@sspr.com

Posted by: Beverly      Read more         Source


December 9, 2010, 7:13 AM CT

Water-based and silicon-based lubricant

Water-based and silicon-based lubricant
Debby Herbenick of Indiana University.

Credit: Indiana University

A newly released study by sexual health scientists at Indiana University observed that women who used lubricant during sex reported significantly higher levels of satisfaction and pleasure.

The study, involving 2,453 women, is the largest systematic study of this kind, despite the widespread commercial availability of lubricant and the gaps in knowledge concerning its role in alleviating pain or contributing to other health issues.

"In spite of the widespread availability of lubricants in stores and on the Internet, it is striking how little research addresses basic questions of how personal lubricants contribute to the sexual experience," said Debby Herbenick, associate director of the Center for Sexual Health Promotion. "These data clearly show that use of the lubricants in our study was linked to higher ratings of sexual pleasure and satisfaction and low rates of genital symptoms."

While these findings, published in the recent issue of the "Journal of Sexual Medicine," involve the use of water-based and silicone-based lubricant, scientists also observed that study participants reported fewer genital symptoms -- and, in particular, fewer reports of genital pain -- when they used a water-based lubricant.

Michael Reece, director of the Center for Sexual Health Promotion and co-author of the study, said public health professionals have long recommended the use of lubricants as an important safer sex tool, especially when used with latex condoms.........

Posted by: Beverly      Read more         Source


December 8, 2010, 7:17 AM CT

Air Force flight control improvements

Air Force flight control improvements
Virtual reality tunnel for fruit flies allows simultaneous tracking of freely flying flies and computer projected imagery on the walls and floor of the arena.

Credit: Credit: Dr. Andrew Straw, Caltech

Flying insects' altitude control mechanisms are the focus of research being conducted in a Caltech laboratory under an Air Force Office of Scientific Research grant that may lead to technology that controls altitude in a variety of aircraft for the Air Force.

"This work investigates sensory-motor feedback mechanisms in the insect brain that could inspire new approaches to flight stabilization and navigation in future insect-sized vehicles for the military," said Dr. Willard Larkin, AFOSR program manager who's supporting the work of lead researcher, Dr. Andrew Straw of Caltech.

The research is being conducted in a laboratory where researchers are studying how flies use visual information to guide flight in natural environments.

The researchers have observed that, counter to earlier studies suggesting that insects adjust their height by measuring the motion beneath them as they fly, flies in fact follow horizontal edges of objects to regulate altitude. Remarkably, this edge following behavior is very similar to a rule they use for steering left and right and always turning towards vertical edges.

Straw noted that the flies don't have access to GPS or other radio signals that may also be unavailable in, for example, indoor environments.

"However, with a tiny brain they are able to perform a variety of tasks such as finding food and mates despite changing light levels, wind gusts, wing damage, and so on," he said. "Flies rely heavily on vision".........

Posted by: Beverly      Read more         Source


December 8, 2010, 7:03 AM CT

Feeling chills in response to music

Feeling chills in response to music
Most people feel chills and shivers in response to music that thrills them, but some people feel these chills often and others feel them hardly at all. People who are especially open to new experiences are most likely to have chills in response to music, as per a research studyin the current Social Psychological and Personality Science (published by SAGE).

Scientists Emily Nusbaum and Paul Silvia of University of North Carolina at Greensboro asked students about how often they felt chills down their spine, got goose bumps, or felt like their hair was standing on end while listening to music. They also measured their experience with music, and five main dimensions of personality: extraversion, conscientiousness, agreeableness, neuroticism, and openness to experience. Of all these dimensions, only openness to experience was correlation to feeling chills. People high in openness are creative, curious about a number of things, have active imaginations and like to play with ideas, and they much more frequently feel chills in response to music.

Why might people high in openness to experience report feeling chills more often? Surprisingly, people high in openness didn't have chills because they tended to listen to different kinds of music. Instead, people with a lot of openness to experience were more likely to play a musical instrument themselves and they rated music as more important in their lives than people low in openness. Not surprisingly, people high in openness also spent more time listening to music.........

Posted by: Beverly      Read more         Source


December 7, 2010, 7:18 AM CT

Unraveling mysteries of repetitive DNA segments

Unraveling mysteries of repetitive DNA segments
Rice physicists use an atomic force microscope to grab and stretch individual strands of DNA.

Credit: C. Kiang/Rice University

With new tools that can grab individual strands of DNA and stretch them like rubber bands, Rice University researchers are working to unravel a mystery of modern genomics. Their latest findings, which appear in Physical Review Letters, offer new clues about the physical makeup of odd segments of DNA that have just one DNA base, adenine, repeated dozens of times in a row.

These mysterious "poly(dA) repeats" are sprinkled throughout the human genome. Researchers have also found them in the genomes of animals, plants and other species over the past decade. But scientists do not know why they are there, what function they perform or why they occur only with the DNA base adenine and not the other three DNA bases -- cytosine, guanine and thymine.

"Prior investigations of poly(dA) have suggested that adenine bases stack in a very uniform way," said Ching-Hwa Kiang, a co-author of the newly released study and assistant professor of physics and astronomy at Rice. "Our investigation focused on what happens when single strands of poly(dA) were stretched and these stacks were pulled apart".

Kiang's research group specializes in studying the physical and mechanical properties of proteins and nucleic acids, and their primary tool is one of the mainstays of nanotechnology research -- the atomic force microscope, or AFM. The business end of an AFM is like a tiny phonograph needle. The tip of the needle is no more than a few atoms wide, and the needle is at the end of an arm that bobs up and down over the surface of what is being measured. While nanotechnologists use the device to measure the thickness of samples, Kiang's group uses it in a different way.........

Posted by: Beverly      Read more         Source


November 18, 2010, 7:32 AM CT

Antimatter atoms produced and trapped

Antimatter atoms produced and trapped
An artist's impression of an antihydrogen atom -- a negatively charged antiproton orbited by a positively charge anti-electron, or positron -- trapped by magnetic fields.

Credit: Graphic by Katie Bertsche

The ALPHA experiment at CERN has taken an important step forward in developing techniques to understand one of the Universe's open questions: is there a difference between matter and antimatter? In a paper published in Nature today, the collaboration shows that it has successfully produced and trapped atoms of antihydrogen. This development opens the path to new ways of making detailed measurements of antihydrogen, which will in turn allow researchers to compare matter and antimatter.

Antimatter or the lack of it remains one of the biggest mysteries of science. Matter and its counterpart are identical except for opposite charge, and they annihilate when they meet. At the Big Bang, matter and antimatter should have been produced in equal amounts. However, we know that our world is made up of matter: antimatter seems to have disappeared. To find out what has happened to it, researchers employ a range of methods to investigate whether a tiny difference in the properties of matter and antimatter could point towards an explanation.

One of these methods is to take one of the best-known systems in physics, the hydrogen atom, which is made of one proton and one electron, and check whether its antimatter counterpart, antihydrogen, consisting of an antiproton and a positron, behaves in the same way. CERN is the only laboratory in the world with a dedicated low-energy antiproton facility where this research can be carried out.........

Posted by: Beverly      Read more         Source


November 8, 2010, 8:08 AM CT

'Prima donna' protein doesn't work well in pairs

'Prima donna' protein doesn't work well in pairs
Rice University researchers tethered pairs of kinesin motor proteins to plastic beads and measured their pulling power. They found the two-legged proteins, which are relatively fast and efficient on their own, had trouble keeping up with one another when they were connected.

Credit: Kenneth Jamison/Rice University

A newly released study by Rice University bioengineers finds that the workhorse proteins that move cargo inside living cells behave like prima donnas. The protein, called kinesin, is a two-legged molecular machine. Rice's researchers invented tools that could measure the pulling power of kinesin both singly and in pairs, and they report this week in Biophysical Journal that kinesins don't work well together -- in part because they are so effective on their own.

"Scientists have been investigating the mechanical properties of individual motor proteins for some time now, but this is the first time anyone's been able to tie a defined number of molecular motors to a cargo and watch them work together," said lead researcher Michael Diehl, assistant professor in bioengineering at Rice. "We know that more than one of these motors is attached to most cargoes, so understanding how they work together -- or fail to -- is a key to better understanding the intracellular transport system".

Cargoes inside cells are hitched to teams of motor proteins and hauled from place to place like horse-drawn wagons. Like stagecoaches or wagons, a number of cargoes are pulled by several horses. But unlike a wagon, cellular cargoes often also have multiple teams pulling in opposite directions.........

Posted by: Beverly      Read more         Source


November 8, 2010, 7:32 AM CT

The many faces of the shear Alfvn wave

The many faces of the shear Alfvn wave
This is a representation of the three-dimensional magnetic field (due to four currents threading the center of each helix) of a shear Alfven wave. It was acquired at an instant of time throughout the volume of a large (60 cm diameter ,18m long) plasma in the LAPD device at UCLA. The currents and the field topology change in fractions of a millionth of a second. The sparkles are proportional to the electric field in the plasma induced by the wave.

Credit: Walter Gekelman, UCLA

When physicists probe the mysteries of plasma, the fourth state of matter, they often discover phenomena of striking beauty. Much as when the Hubble Space Telescope sent back vivid images from space of ionized gas clouds (an interstellar plasma!), new 3D images of shear Alfvn waves are delighting both researchers and a new generation of science enthusiasts.

Plasmas support a large variety of waves. Some of these are familiar, such as light and sound waves, but a great a number of exist nowhere else. One of the fundamental waves in magnetized plasma is the shear Alfvn wave, named after Nobel Prize winning scientist Hannes Alfvn, who predicted their existence.

Shear waves of various forms have been a topic of experimental research for more than 15 years in the Large Plasma Device (LAPD) at the University of California, Los Angeles. When the waves were first studied, it was discovered that their creation gives rise to exotic spatial patterns, such as the one shown in Figure 1, all of them Shear Alfvn waves. Three-dimensional data, such as the magnetic field of the wave shown here, will be presented along with relevant theory. Part of the presentation will be in 3D!

It has become apparent that Alfvn waves are important in a wide variety of physical environments. They play a central role in the stability of the magnetic confinement devices used in fusion research, give rise to aurora formation in planets, and are thought to contribute to heating and ion acceleration in the solar corona. Shear waves can also cause particle acceleration over considerable distances in interstellar space.........

Posted by: Beverly      Read more         Source


November 5, 2010, 7:45 AM CT

Hotspots for Calcium-related Disease

Hotspots for Calcium-related Disease
High-resolution images of the ryanodine receptor, a protein associated with calcium-related disease, reveal in unprecedented detail the locations of more than 50 mutations that cluster in disease "hotspots" along the receptor. The grey portion of the above image represents low-resolution information about the entire receptor. The high-resolution structure is shown in blue, where each sphere represents a single atom. Mutations identified in individual amino acids are colored red. (Image courtesy of Filip Van Petegem/University of British Columbia.)
Calcium regulates a number of critical processes within the body, including muscle contraction, the heartbeat, and the release of hormones. But too much calcium can be a bad thing. In excess, it can lead to a host of diseases, such as severe muscle weakness, a fatal reaction to anesthesia or sudden cardiac death.

Now, using intense X-rays from the Stanford Synchrotron Radiation Lightsource (SSRL) at the Department of Energy's SLAC National Accelerator Laboratory, scientists have determined the detailed structure of a key part of the ryanodine receptor, a protein linked to calcium-related disease. Their results, which combine data from SSRL and the Canadian Light Source, pinpoint the locations of more than 50 mutations that cluster in disease "hotspots" along the receptor.

"Until now, no one could tell where these disease mutations were located or what they were doing," said principal investigator Filip Van Petegem of the University of British Columbia in Vancouver.

The ryanodine receptor controls the release of calcium ions from a storehouse within skeletal-muscle and heart-muscle cells as needed to perform critical functions. Prior studies at lower resolution indicated that mutations cluster in three regions along the receptor, but without more detailed information it remained unclear exactly how they contributed to disease.........

Posted by: Beverly      Read more         Source


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