Humans were already recycling 13,000 years ago, burnt artifacts show

ScienceDaily (Sep. 20, 2012) — A study at the Universitat Rovira i Virgili and the Catalan Institute of Human Paleoecology and Social Evolution (IPHES) reveals that humans from the Upper Palaeolithic Age recycled their stone artefacts to be put to other uses. The study is based on burnt artefacts found in the Molí del Salt site in Tarragona, Spain.

The recycling of stone tools during Prehistoric times has hardly been dealt with due to the difficulties in verifying such practices in archaeological records. Nonetheless, it is possible to find some evidence, as demonstrated in a study published in the 'Journal of Archaeological Science'.

"In order to identify the recycling, it is necessary to differentiate the two stages of the manipulation sequence of an object: the moment before it is altered and the moment after. The two are separated by an interval in which the artefact has undergone some form of alteration. This is the first time a systematic study of this type has been performed," as explained to SINC by Manuel Vaquero, researcher at the Universitat Rovira i Virgili.

The archaeologists found a high percentage of burnt remains in the Molí del Salt site (Tarragona), which date back to the end of the Upper Palaeolithic Age some 13,000 years ago. The expert ensures that "we chose these burnt artefacts because they can tell us in a very simple way whether they have been modified after being exposed to fire."

The results indicate that the recycling of tools was normal during the Upper Palaeolithic Age. However, this practice is not documented in the same way as other types of artefacts. The use of recycled tools was more common for domestic activities and seems to be associated with immediate needs.

Recycling domestic tools

Recycling is linked to expedited behaviour, which means simply shaped and quickly available tools as and when the need arises. Tools used for hunting, like projectile points for instance, were almost never made from recycled artefacts. In contrast, double artefacts (those that combine two tools within the same item) were recycled more often.

"This indicates that a large part of these tools were not conceived from the outset as double artefacts but a single tool was made first and a second was added later when the artefact was recycled," outlines the researcher. The history of the artefacts and the sequence of changes that they have undergone over time are fundamental in understanding their final morphology.

According to Vaquero, "in terms of the objects, this is mostly important from a cultural value point of view, especially in periods like the Upper Palaeolithic Age, in which it is thought that the sharper the object the sharper the mind."

Sustainable practices with natural resources

Recycling could have been determinant in hunter-gatherer populations during the Palaeolithic Age if we consider the behaviour of current indigenous populations nowadays.

"It bears economic importance too, since it would have increased the availability of lithic resources, especially during times of scarcity. In addition, it is a relevant factor for interpreting sites because they become not just places to live but also places of resource provision," states the researcher.

Reusing resources meant that these humans did not have to move around to find raw materials to make their tools, a task that could have taken them far away from camp. "They would simply take an artefact abandoned by those groups who previously inhabited the site."

Vaquero and the team believe that this practice needs to be borne in mind when analysing the site. "Those populating these areas could have moved objects from where they were originally located. They even could have dug up or removed sediments in search of tools," highlights the researcher.

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The above story is reprinted from materials provided by Plataforma SINC, via AlphaGalileo.

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Journal Reference:

1. Manuel Vaquero, Susana Alonso, Sergio García-Catalán, Angélica García-Hernández, Bruno Gómez de Soler, David Rettig, María Soto. Temporal nature and recycling of Upper Paleolithic artifacts: the burned tools from the Molí del Salt site (Vimbodí i Poblet, northeastern Spain). Journal of Archaeological Science, 2012; 39 (8): 2785 DOI: 10.1016/j.jas.2012.04.024

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20 Sep, 2012

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Olympic Games in Rio 2016: Mathematical formula can predict medal haul, including impact of home advantage

ScienceDaily (Sep. 19, 2012) — Team GB is only likely to clock up 46 medals in the Olympic Games in Rio in 2016, say researchers who used a mathematical formula three years ago to predict performance for London 2012, and came up with a medal haul of 63.

In the end, Team GB won 65 medals in London, so the prediction was only out by two.

The formula, published in the British Journal of Sports Medicine, is based on all cities and countries that have hosted the Olympic Games since World War II and the number of medals awarded to competitors from each country.

The approach, known as logit regression, takes into account medal tallies achieved before, during, and after hosting the Games, and includes the impact of home advantage.

The formula suggests that the odds of winning medals when hosting the Games, roughly doubles (2.05). So looking at the average tally for Britain's athletes since World War II produces a figure of 31, which when multiplied by 2.05, indicates 63.5 medals.

Home advantage has little or no influence on sports that are objectively judged, such as athletics, swimming and weightlifting. But it does seem to have a role in sports that are either subjectively judged such as boxing, equestrian/dressage and gymnastics, or those which rely on subjective decisions, such as team games, say the authors.

Team GB made 13 medal gains in subjectively assessed sports in London 2012, compared with Beijing in 2008, but only a five medal gain in objectively assessed sports.

"Anecdotal evidence suggests that the crowd had a positive effect on athletes to raise their performance, but also, based on these results, crowds appear to have had an important effect on influencing officials to favour the home based performers, and hence increase their medal winning capacity," write the authors.

Historically the medal haul has dropped off in hosting nations by the time of the next Games, the figures show.

The formula reduces the odds of winning medals to 1.46 without the home advantage, so multiplying that by 31 gives a total medal haul for Team GB of 45 or 46 medals in Rio in 2016, roughly the same as the tally in Beijing in 2008.

Funding will clearly be important in helping to temper this decline, say the authors, who note Prime Minister David Cameron's pledge to maintain funding for elite sports, but add that "the current and projected economic situation presents some stern challenges."

The authors emphasise that Team GB's accomplishments were "a testament to the achievements of athletes and their coaches" and a "source of delight and pride for spectators."

But they add: "However, it seems unlikely that even maintained funding can make up for the benefits of a partisan London crowd."

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The above story is reprinted from materials provided by BMJ-British Medical Journal.

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Journal Reference:

1. Alan M Nevill, Nigel J Balmer, Edward M Winter. Congratulations to team GB, but why should we be so surprised? Olympic medal count can be predicted using logit regression models that include 'home advantage'. British Journal of Sports Medicine, 2012; DOI: 10.1136/bjsports-2012-091719

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20 Sep, 2012

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Invasive 'Rasberry Crazy Ant' in Texas now identified species

ScienceDaily (Sep. 19, 2012) — The Rasberry Crazy Ant is an invasive ant that was first noticed infesting areas around Houston, Texas ten years ago, but its species identity has remained undetermined until now.

In a paper published Sept. 19 in the open access journal PLOS ONE, a research team led by John LaPolla from Towson University in Maryland identifies the species as Nylanderia fulva. Identifying the species should help control this emerging pest, the authors write.

They also conclude that the species, whose common name comes from exterminator Tom Rasberry who first noticed the ants, is distributed more widely than previously thought and has likely invaded all Gulf Coast states.

"This study demonstrates the invaluable role that taxonomy, an often underappreciated discipline, plays in our understanding of emerging pests. Now that we know just what species the Rasberry Crazy Ant really is, we can better understand its biology to improve control of this invasive species," says LaPolla.

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1. Dietrich Gotzek, Seán G. Brady, Robert J. Kallal, John S. LaPolla. The Importance of Using Multiple Approaches for Identifying Emerging Invasive Species: The Case of the Rasberry Crazy Ant in the United States. PLoS ONE, 2012; 7 (9): e45314 DOI: 10.1371/journal.pone.0045314

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20 Sep, 2012

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Obese children have less sensitive taste-buds than those of normal weight

ScienceDaily (Sep. 19, 2012) — Obese kids have less sensitive taste-buds than kids of normal weight, indicates research published online in the Archives of Disease in Childhood.

This blunted ability to distinguish all five tastes of bitter, sweet, salty, sour, and umami (savoury) may prompt them to eat larger quantities of food in a bid to register the same taste sensation, suggest the authors.

They base their findings on 94 normal weight and 99 obese children aged between 6 and 18, who were in good health and not taking any medications known to affect taste and smell.

The taste sensitivity of every child was tested using 22 "taste strips" placed on the tongue, to include each of the five taste sensations, at four different levels of intensity, plus two blank strips.

Each child was asked to refrain from eating or drinking anything other than water and not to chew gum for at least an hour before they took the two tests, which involved identifying the different tastes and their intensity.

The sum of all five taste sensations at the four different intensities allowed for a maximum score of 20, with scores ranging from two to 19.

Girls and older children were better at picking out the right tastes.

Overall, the children were best able to differentiate between sweet and salty, but found it hardest to distinguish between salty and sour, and between salty and umami.

And obese children found it significantly more difficult to identify the different taste sensations, scoring an average of 12.6 compared with an average of just over 14 clocked up by children of normal weight.

Obese children were significantly less likely to identify the individual taste sensations correctly, particularly salty, umami, and bitter.

And while both obese and normal weight children correctly identified all the differing levels of sweetness, obese kids rated three out of the four intensity levels lower than kids of normal weight.

Similarly, children of normal weight were better able to distinguish the different taste sensations, the older they were, but this trend was not seen among the obese children.

Exactly why people have differing taste perceptions is unclear, but genes, hormones, acculturation and exposure to different tastes early in life are all thought to play a part, say the authors.

But previous research indicates that heightened sensitivity to different taste sensations may help to reduce the amount of food eaten as less is required to get the same "taste hit."

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Journal Reference:

1. Johanna Overberg, Thomas Hummel, Heiko Krude, Susanna Wiegand. Differences in taste sensitivity between obese and non-obese children and adolescents. Archives of Disease in Childhood, 2012; DOI: 10.1136/archdischild-2011-301189

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20 Sep, 2012

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Clenching left hand could help athletes avoid choking under pressure

ScienceDaily (Sep. 19, 2012) — Some athletes may improve their performance under pressure simply by squeezing a ball or clenching their left hand before competition to activate certain parts of the brain, according to new research published by the American Psychological Association.

In three experiments with experienced soccer players, judo experts and badminton players, researchers in Germany tested the athletes' skills during practice and then in stressful competitions before a large crowd or video camera. Right-handed athletes who squeezed a ball in their left hand before competing were less likely to choke under pressure than right-handed players who squeezed a ball in their right hand. The study was published online in the Journal of Experimental Psychology: General.

For skilled athletes, many movements, such as kicking a soccer ball or completing a judo kick, become automatic with little conscious thought. When athletes under pressure don't perform well, they may be focusing too much on their own movements rather than relying on their motor skills developed through years of practice, said lead researcher Juergen Beckmann, PhD, chair of sport psychology at the Technical University of Munich in Germany.

"Rumination can interfere with concentration and performance of motor tasks. Athletes usually perform better when they trust their bodies rather than thinking too much about their own actions or what their coaches told them during practice," Beckmann said. "While it may seem counterintuitive, consciously trying to keep one's balance is likely to produce imbalance, as was seen in some sub-par performances by gymnasts during the Olympics in London."

Previous research has shown that rumination is associated with the brain's left hemisphere, while the right hemisphere is associated with superior performance in automated behaviors, such as those used by some athletes, the study notes. The right hemisphere controls movements of the left side of the body, and the left hemisphere controls the right side. The researchers theorized that squeezing a ball or clenching the left hand would activate the right hemisphere of the brain and reduce the likelihood of the athlete's choking under pressure. The study focused exclusively on right-handed athletes because some relationships between different parts of the brain aren't as well understood for left-handed people, according to the authors.

The research could have important implications outside athletics. Elderly people who are afraid of falling often focus too much on their movements, so right-handed elderly people may be able to improve their balance by clenching their left hand before walking or climbing stairs, Beckmann said.

"Many movements of the body can be impaired by attempts at consciously controlling them," he said. "This technique can be helpful for many situations and tasks."

In the first experiment, 30 semi-professional male soccer players took six penalty shots during a practice session. The next day, they attempted to make the same penalty shots in an auditorium packed with more than 300 university students waiting to see a televised soccer match between Germany and Austria. The players who squeezed a ball with their left hand performed as well under pressure as during practice, while players who squeezed a ball in their right hand missed more shots in the crowded auditorium.

Twenty judo experts (14 men and six women) took part in the second experiment. First, they performed a series of judo kicks into a sandbag during practice. During a second session, they were told that their kicks would be videotaped and evaluated by their coaches. The judo athletes who squeezed a ball with their left hand not only didn't choke under pressure, they performed better overall during the stressful competition than during practice, while those in the control group choked under pressure, the study found.

The final experiment featured 18 experienced badminton players (12 men and six women) who completed a series of practice serves. Then, they were divided into teams and competed against each other while being videotaped for evaluation by their coaches. Athletes who squeezed a ball in their left hand didn't choke under pressure, unlike the control group players who squeezed a ball in their right hand. A final phase of the experiment had the athletes just clench their left or right hand without a ball before competition, and players who clenched their left hand performed better than players who squeezed their right hand.

The ball-squeezing technique probably wouldn't help athletes whose performance is based on strength or stamina, such as weightlifters or marathon runners, the authors noted. The effects apply to athletes whose performance is based on accuracy and complex body movements, such as soccer players or golfers, they said.

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The above story is reprinted from materials provided by American Psychological Association (APA), via Newswise.

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Journal Reference:

1. Jürgen Beckmann, Peter Gröpel, Felix Ehrlenspiel. Preventing Motor Skill Failure Through Hemisphere-Specific Priming: Cases From Choking Under Pressure.. Journal of Experimental Psychology: General, 2012; DOI: 10.1037/a0029852

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20 Sep, 2012

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Protecting our harbors and ships with a robotic tuna fish

ScienceDaily (Sep. 19, 2012) — No question about it… they're very good at what they do. But they don't take well to orders, especially those to carry out inspection work in oily or dangerous environments, or in any kind of harsh environment, for that matter. Still, they're one of the fastest and most maneuverable creatures on the planet, having extraordinary abilities at both high and low speeds due to their streamlined bodies and a finely tuned muscular/sensory/control system.

This impressive creature is the humble tuna fish.

The Department of Homeland Security's (DHS) Science and Technology Directorate (S&T) is funding the development of an unmanned underwater vehicle designed to resemble a tuna, called the BIOSwimmer™. Why the tuna? Because the tuna has a natural body framework ideal for unmanned underwater vehicles (UUVs), solving some of the propulsion and maneuverability problems that plague conventional UUVs.

Inspired by the real tuna, BIOSwimmer™ is a UUV designed for high maneuverability in harsh environments, with a flexible aft section and appropriately placed sets of pectoral and other fins. For those cluttered and hard-to-reach underwater places where inspection is necessary, the tuna-inspired frame is an optimal design. It can inspect the interior voids of ships such as flooded bilges and tanks, and hard to reach external areas such as steerage, propulsion and sea chests. It can also inspect and protect harbors and piers, perform area searches and carry out other security missions.

Boston Engineering Corporation's Advanced Systems Group (ASG) in Waltham, Massachusetts, is developing the BIOSwimmer™ for Homeland Security's Science and Technology Directorate. "It's designed to support a variety of tactical missions and with its interchangeable sensor payloads and reconfigurable Operator Controls, and can be optimized on a per-mission basis," says the Director of ASG, Mike Rufo.

BIOSwimmer™ is battery-powered and designed for long-duration operation. Like other unmanned underwater vehicles, it uses an onboard computer suite for navigation, sensor processing, and communications. Its Operator Control Unit is laptop-based and provides intuitive control and simple, mission-defined versatility for the user. A unique aspect of this system is the internal components and external sensing which are designed for the challenging environment of constricted spaces and high viscosity fluids

"It's all about distilling the science," says David Taylor, program manager for the BIOSwimmer™ in S&T's Borders and Maritime Security Division. "It's called 'biomimetics.' We're using nature as a basis for design and engineering a system that works exceedingly well.

Tuna have had millions of years to develop their ability to move in the water with astounding efficiency. Hopefully we won't take that long."

Background

Biologically inspired robotics (biomimetic robotry) is a fairly new science that is gaining steam. There are now robotic lobsters, flies, geckos, moths, clams, dogs, and even a lamprey-like robot, all being designed to perform a variety of missions including surveillance and search and rescue. Robotics based on sinuous snakes and elephant trunks, for example, may be the ideal way to search for survivors inside the rubble of structures destroyed by explosions or natural disasters.

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20 Sep, 2012

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Blind people develop accurate mental map by playing 'video' game

ScienceDaily (Sep. 19, 2012) — Researchers have developed a new "video" game for blind people that can help them learn about a new space using only audio cues, as reported Sept. 19 in the open access journal PLOS ONE.

The system, developed by a team led by Lotfi Merabet of Harvard Medical School and Jaime Sánchez of the University of Chile, is called the Audiobased Environment Simulator and uses only audio-based cues to allow blind users to learn about the layout of a previously unfamiliar building.

After playing the game, participants were better able to navigate a real-world version of the space explored in the virtual reality environment, confirming that the spatial information learned in the game was accurate and transferrable.

"Learning through such interactive games represents an innovative and motivating way to improve crucial skills that allow blind individuals to remain functionally independent," says Merabet.

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1. Lotfi B. Merabet, Erin C. Connors, Mark A. Halko, Jaime Sánchez. Teaching the Blind to Find Their Way by Playing Video Games. PLoS ONE, 2012; 7 (9): e44958 DOI: 10.1371/journal.pone.0044958

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20 Sep, 2012

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People change moral position without even realizing it

ScienceDaily (Sep. 19, 2012) — Shortly after expressing a moral view about a difficult topic, people may easily endorse the opposite view and remain blind to the psychological mismatch, according to research published Sept. 19 in the open access journal PLOS ONE.

In the study, led by Lars Hall of Lund University, Sweden, participants were presented with a survey about moral issues, including foundational principles and current hot topics with moral implications. To complete the survey they had to flip over the first page of questions, which was displayed on a clipboard, and this is where the researchers implemented a design usually used in performance magic: the back of the clipboard had a patch of glue that caught the top layer of the questions, so when the page was flipped back over, an opposite version of the original questions was revealed but the answers remained unchanged. In other words, the participants' responses were opposite to their originally declared positions (For a video illustration of the experiment, see http://www.lucs.lu.se/cbq/).

The researchers then discussed the participants' answers with them, and found that many participants supported their reported answers, even though the responses were opposite to what the individual had originally intended to express. The authors write that "participants often constructed coherent and unequivocal arguments supporting the opposite of their original position," suggesting "a dramatic potential for flexibility in our moral attitudes."

Commenting on their results, Lars Hall says, "It could have significant impact on research that uses self-reported questionnaires. Either we would have to conclude that many participants hold no real attitudes about the topics we investigate, or that standard survey scales fail to capture the complexity of the attitudes people actually hold."

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1. Lars Hall, Petter Johansson, Thomas Strandberg. Lifting the Veil of Morality: Choice Blindness and Attitude Reversals on a Self-Transforming Survey. PLoS ONE, 2012; 7 (9): e45457 DOI: 10.1371/journal.pone.0045457

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20 Sep, 2012

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Ancient tooth may provide evidence of early human dentistry

ScienceDaily (Sep. 19, 2012) — Researchers may have uncovered new evidence of ancient dentistry in the form of a 6,500-year-old human jaw bone with a tooth showing traces of beeswax filling, as reported Sep. 19 in the open access journal PLOS ONE.

The researchers, led by Federico Bernardini and Claudio Tuniz of the Abdus Salam International Centre for Theoretical Physics in Italy in cooperation with Sincrotrone Trieste and other institutions, write that the beeswax was applied around the time of the individual's death, but cannot confirm whether it was shortly before or after. If it was before death, however, they write that it was likely intended to reduce pain and sensitivity from a vertical crack in the enamel and dentin layers of the tooth.

According to Tuniz, the severe wear of the tooth "is probably also due to its use in non-alimentary activities, possibly such as weaving, generally performed by Neolithic females."

Evidence of prehistoric dentistry is sparse, so this new specimen, found in Slovenia near Trieste, may help provide insight into early dental practices.

"This finding is perhaps the most ancient evidence of pre-historic dentistry in Europe and the earliest known direct example of therapeutic-palliative dental filling so far," says Bernardini.

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1. Federico Bernardini, Claudio Tuniz, Alfredo Coppa, Lucia Mancini, Diego Dreossi, Diane Eichert, Gianluca Turco, Matteo Biasotto, Filippo Terrasi, Nicola De Cesare, Quan Hua, Vladimir Levchenko. Beeswax as Dental Filling on a Neolithic Human Tooth. PLoS ONE, 2012; 7 (9): e44904 DOI: 10.1371/journal.pone.0044904

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20 Sep, 2012

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Odorant shape and vibration likely lead to olfaction satisfaction

ScienceDaily (Sep. 19, 2012) — A new study of the sense of smell lends support to a controversial theory of olfaction: Our noses can distinguish both the shape and the vibrational characteristics of odorant molecules.

The study, in the journal Physical Chemistry Chemical Physics, demonstrates the feasibility of the theory -- first proposed decades ago -- that the vibration of an odorant molecule's chemical bonds -- the wagging, stretching and rocking of the links between atoms -- contributes to our ability to distinguish one smelly thing from another.

"The theory goes that when the right odorant binds to its receptor, the odorant's molecular vibration allows electrons to transfer from one part of the receptor to another," said University of Illinois physics and Beckman Institute professor Klaus Schulten, who conducted the analysis with postdoctoral researcher Ilia Solov'yov and graduate student Po-Yao Chang. "This electron transfer appears to fine-tune the signal the receptor receives."

Many who study olfaction maintain that odorant receptors recognize only an odorant's shape and surface characteristics. They dismiss the idea that molecular vibration has anything to do with it, Schulten said. Likewise, some proponents of the vibrational theory think that molecular vibration only, and not shape, guides the sense of smell. Schulten and his colleagues belong to a "third camp" that sees evidence for both, he said.

The vibrational theory of olfaction is supported by studies showing that insects, humans and other animals can tell the difference between two versions of the same odorant molecule -- a normal one and an identical one with deuterium atoms substituted for each of the hydrogens. The deuterated and normal versions of the odorant have the same shape and surface characteristics, and yet humans and other animals can smell the difference, Schulten said.

"The question then is of course, for scientists, how does this happen?" he said.

To answer this question, Schulten turned to the work of a former colleague at Illinois, Rudolph Marcus, a chemist (now at the California Institute of Technology) who received the Nobel Prize in Chemistry in 1992 for his insights into electron transfer, one of the most basic forms of a chemical reaction.

"Marcus realized that when electrons are being exchanged between molecules the process is coupled to the vibrations of the molecules involved," Schulten said. Marcus focused primarily on the low-frequency "rumblings" that occur as a result of molecular vibration in large molecules, Schulten said.

Odorant molecules are generally quite small, however, with a lot of high-frequency, high-energy vibrations, Schulten said. Some scientists have theorized that these high-frequency vibrations can, when an odorant binds to the right receptor, enhance the likelihood that an electron will transfer from one part of the receptor to another, sending an electrical signal that contributes to the detection of that odor.

Prior to the new study, no one had analyzed the energetics of the system to see if the vibrations of the odorant molecules -- in the context of all the background vibrations that are part of the system -- could actually promote electron transfer within the receptor. Schulten and his colleagues are the first to conduct such an analysis, he said.

"You can actually carry out quantum chemical calculations that determine very precisely the vibration of the molecule as well as the ability to couple it to electron transfer," Schulten said. The calculations indicate that such an interaction is energetically feasible, he said.

Odorant receptors are embedded in membranes and so are more difficult to study than other proteins. But previous research indicates that some receptors are metalloproteins, and "the metals in the proteins are predesigned to transfer electrons," Schulten said. "We also see that there are other amino acid side groups that can accept an electron, so the electron can be transferred through the protein."

Like others before them, Schulten and his colleagues suggest that the odorant receptor contains both an electron donor and an electron acceptor, but that electron transfer occurs only when a specific odorant is bound to the receptor. The new calculations offer the first quantitative evidence that the odorant can in fact promote electron transfer.

Those who suggested that molecular vibration played a role in odorant recognition in previous studies "didn't know about Marcus' theory and they didn't do quantum chemical calculations," Schulten said. "They argued very much on principle (that it was possible). So we are saying now, yes, it is really possible even when you do the most complete and reliable calculations."

Video: http://www.youtube.com/watch?v=Oe5PW2KqImI

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Journal Reference:

1. Ilia A. Solov'yov, Po-Yao Chang, Klaus Schulten. Vibrationally assisted electron transfer mechanism of olfaction: myth or reality? Physical Chemistry Chemical Physics, 2012; DOI: 10.1039/C2CP41436H

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20 Sep, 2012

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Revolutionary ultrathin, flat lens: Smartphones as thin as a credit card?

ScienceDaily (Sep. 19, 2012) — Scientists are reporting development of a revolutionary new lens -- flat, distortion-free, so small that more than 1,500 would fit across the width of a human hair -- capable in the future of replacing lenses in applications ranging from cell phones to cameras to fiber-optic communication systems. The advance, which could lead to smart phones as thin as a credit card, appears in ACS' journal Nano Letters.

Federico Capasso and colleagues explain that the lenses used to focus light in eyeglasses, microscopes and other products use the same basic technology dating to the late 1200s, when spectacle lenses were introduced in Europe. Existing lenses are not thin or flat enough to remove distortions, such as spherical aberration, astigmatism and coma, which prevent the creation of a sharp image. Correction of those distortions requires complex solutions, such as multiple lenses that increase weight and take up space. To overcome these challenges, the scientists sought to develop a new superthin, flat lens.

Although the new lens is ultra-thin, it has a resolving power that actually approaches the theoretical limits set by the laws of optics. The lens surface is patterned with tiny metallic stripes which bend light differently as one moves away from the center, causing the beam to sharply focus without distorting the images. The current version of the lens works at a specific design wavelength, but the scientists say it can be redesigned for use with broad-band light.

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Journal Reference:

1. Francesco Aieta, Patrice Genevet, Mikhail A. Kats, Nanfang Yu, Romain Blanchard, Zeno Gaburro, Federico Capasso. Aberration-Free Ultrathin Flat Lenses and Axicons at Telecom Wavelengths Based on Plasmonic Metasurfaces. Nano Letters, 2012; 12 (9): 4932 DOI: 10.1021/nl302516v

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20 Sep, 2012

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Single-atom writer a landmark for quantum computing

ScienceDaily (Sep. 19, 2012) — A research team led by Australian engineers has created the first working quantum bit based on a single atom in silicon, opening the way to ultra-powerful quantum computers of the future.

In a landmark paper published September 19 in the journal Nature, the team describes how it was able to both read and write information using the spin, or magnetic orientation, of an electron bound to a single phosphorus atom embedded in a silicon chip.

"For the first time, we have demonstrated the ability to represent and manipulate data on the spin to form a quantum bit, or 'qubit', the basic unit of data for a quantum computer," says Scientia Professor Andrew Dzurak. "This really is the key advance towards realising a silicon quantum computer based on single atoms."

Dr Andrea Morello and Professor Dzurak from the UNSW School of Electrical Engineering and Telecommunications lead the team. It includes researchers from the University of Melbourne and University College, London.

"This is a remarkable scientific achievement -- governing nature at its most fundamental level -- and has profound implications for quantum computing," says Dzurak.

Dr Morello says that quantum computers promise to solve complex problems that are currently impossible on even the world's largest supercomputers: "These include data-intensive problems, such as cracking modern encryption codes, searching databases, and modelling biological molecules and drugs."

The new finding follows on from a 2010 study also published in Nature, in which the same UNSW group demonstrated the ability to read the state of an electron's spin. Discovering how to write the spin state now completes the two-stage process required to operate a quantum bit.

The new result was achieved by using a microwave field to gain unprecedented control over an electron bound to a single phosphorus atom, which was implanted next to a specially-designed silicon transistor. Professor David Jamieson, of the University of Melbourne's School of Physics, led the team that precisely implanted the phosphorus atom into the silicon device.

UNSW PhD student Jarryd Pla, the lead author on the paper, says: "We have been able to isolate, measure and control an electron belonging to a single atom, all using a device that was made in a very similar way to everyday silicon computer chips."

As Dr Morello notes: "This is the quantum equivalent of typing a number on your keyboard. This has never been done before in silicon, a material that offers the advantage of being well understood scientifically and more easily adopted by industry. Our technology is fundamentally the same as is already being used in countless everyday electronic devices, and that's a trillion-dollar industry."

The team's next goal is to combine pairs of quantum bits to create a two-qubit logic gate -- the basic processing unit of a quantum computer.

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The above story is reprinted from materials provided by University of New South Wales, via EurekAlert!, a service of AAAS.

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Journal Reference:

1. Jarryd J. Pla, Kuan Y. Tan, Juan P. Dehollain, Wee H. Lim, John J. L. Morton, David N. Jamieson, Andrew S. Dzurak, Andrea Morello. A single-atom electron spin qubit in silicon. Nature, 2012; DOI: 10.1038/nature11449

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20 Sep, 2012

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Ultra-distant galaxy discovered amidst cosmic 'dark ages': May be oldest galaxy ever

ScienceDaily (Sep. 19, 2012) — With the combined power of NASA's Spitzer and Hubble space telescopes as well as a cosmic magnification effect, a team of astronomers led by Wei Zheng of The Johns Hopkins University has spotted what could be the most distant galaxy ever detected.

Light from the young galaxy captured by the orbiting observatories shone forth when the 13.7-billion-year-old universe was just 500 million years old.

The far-off galaxy existed within an important era when the universe began to transit from the so-called "Dark Ages." During this period, the universe went from a dark, starless expanse to a recognizable cosmos full of galaxies. The discovery of the faint, small galaxy accordingly opens up a window into the deepest, remotest epochs of cosmic history.

"This galaxy is the most distant object we have ever observed with high confidence," said Zheng, a principal research scientist in The Henry A. Rowland Department of Physics and Astronomy at Johns Hopkins' Krieger School of Arts and Sciences and lead author of a paper appearing in Nature on Sept. 20. "Future work involving this galaxy -- as well as others like it that we hope to find -- will allow us to study the universe's earliest objects and how the Dark Ages ended."

Light from the primordial galaxy traveled approximately 13.2 billion light-years before reaching NASA's telescopes. In other words, the starlight snagged by Spitzer and Hubble left the galaxy when the universe was just 3.6 percent of its present age. Technically speaking, the galaxy has a redshift, or "z," of 9.6. The term "redshift" refers to how much an object's light has shifted into longer wavelengths as a result of the expansion of the universe. Astronomers use "redshift" to describe cosmic distances.

Unlike previous detections of galaxy candidates in this age range, which were only glimpsed in a single color, or waveband, this newfound galaxy has been seen in five different wavebands. As part of the Cluster Lensing and Supernova Survey with Hubble program (CLASH), the Hubble Space Telescope registered the newly described far-flung galaxy in four wavelength bands. Spitzer located it in a fifth band with its Infrared Array Camera (IRAC), placing the discovery on firmer ground.

Objects at these extreme distances are mostly beyond the detection sensitivity of today's largest telescopes. To catch sight of these early, distant galaxies, astronomers rely on "gravitational lensing." In this phenomenon -- predicted by Albert Einstein a century ago -- the gravity of foreground objects warps and magnifies the light from background objects. A massive galaxy cluster situated between our galaxy and the early galaxy magnified the latter's light, brightening the remote object some 15 times and bringing it into view.

Based on the Spitzer and Hubble observations, astronomers think the distant galaxy was spied at a time when it was less than 200 million years old. It also is small and compact, containing only about 1 percent of the Milky Way's mass. According to leading cosmological theories, the first galaxies should indeed have started out tiny. They then progressively merged, eventually accumulating into the sizable galaxies of the more modern universe.

These first galaxies likely played the dominant role in the epoch of reionization, the event that signaled the demise of the universe's Dark Ages. About 400,000 years after the Big Bang, neutral hydrogen gas formed from cooling particles. The first luminous stars and their host galaxies, however, did not emerge until a few hundred million years later. The energy released by these earliest galaxies is thought to have caused the neutral hydrogen strewn throughout the universe to ionize, or lose an electron, the state in which the gas has remained since that time.

"In essence, during the epoch of reionization, the lights came on in the universe," said paper co-author Leonidas Moustakas, a research scientist at NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, Calif.

Astronomers plan to study the rise of the first stars and galaxies and the epoch of reionization with the successor to both Spitzer and Hubble -- NASA's James Webb Telescope, slated for launch in 2018. The newly described distant galaxy will likely be a prime target.

Holland Ford, one of Zheng's colleagues and a co-author on the paper, commented on the findings.

"Science is very exciting when we explore the frontiers of knowledge," said Ford, a physics and astronomy professor at Johns Hopkins. "One of these frontiers is the first few hundred million years after the birth of our universe. Dr. Zheng's many years of searching for quasars and galaxies in the dawn of the universe has paid off with his discovery of a galaxy that we see as it was when the universe was less than 500 million years old.

"With his discovery, we are seeing a galaxy when it was not even a toddler," Ford said. "But this infant galaxy will in its future grow to be a galaxy like our own, hopefully hosting planetary systems with astronomers who will look back in time and see our galaxy in its infancy."

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The above story is reprinted from materials provided by Johns Hopkins University, via Newswise. The original article was written by Lisa DeNike.

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Journal Reference:

1. Wei Zheng, Marc Postman, Adi Zitrin, John Moustakas, Xinwen Shu, Stephanie Jouvel, Ole Høst, Alberto Molino, Larry Bradley, Dan Coe, Leonidas A. Moustakas, Mauricio Carrasco, Holland Ford, Narciso Benítez, Tod R. Lauer, Stella Seitz, Rychard Bouwens, Anton Koekemoer, Elinor Medezinski, Matthias Bartelmann, Tom Broadhurst, Megan Donahue, Claudio Grillo, Leopoldo Infante, Saurabh W. Jha, Daniel D. Kelson, Ofer Lahav, Doron Lemze, Peter Melchior, Massimo Meneghetti, Julian Merten, Mario Nonino, Sara Ogaz, Piero Rosati, Keiichi Umetsu, Arjen van der Wel. A magnified young galaxy from about 500 million years after the Big Bang. Nature, 2012; 489 (7416): 406 DOI: 10.1038/nature11446

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20 Sep, 2012

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Monitoring brain activity during study can help predict test performance

ScienceDaily (Sep. 18, 2012) — Research at Sandia National Laboratories has shown that it's possible to predict how well people will remember information by monitoring their brain activity while they study.

A team under Laura Matzen of Sandia's cognitive systems group was the first to demonstrate predictions based on the results of monitoring test volunteers with electroencephalography (EEG) sensors.

For example, "if you had someone learning new material and you were recording the EEG, you might be able to tell them, 'You're going to forget this, you should study this again,' or tell them, 'OK, you got it and go on to the next thing,'" Matzen said.

The team monitored test subjects' brain activity while they studied word lists, then used the EEG to predict who would remember the most information. Because researchers knew the average percentage of correct answers under various conditions, they had a baseline of what brain activity looked like for good and poor memory performance. The computer model predicted five of 23 people tested would perform best. The model was correct: They remembered 72 percent of the words on average, compared to 45 percent for everyone else.

The study is part of Matzen's long-term goal to understand the Difference Related to Subsequent Memory, or Dm Effect, an index of brain activity encoding that distinguishes subsequently remembered from subsequently forgotten items. The measurable difference gives cognitive neuroscientists a way to test hypotheses about how information is encoded in memory.

She's interested in what causes the effect and what can change it, and hopes her research eventually leads to improvements in how students learn. She'd like to discover how training helps people performing at different levels and whether particular training works better for certain groups.

The study, funded under Sandia's Laboratory Directed Research and Development program (LDRD), had two parts: predicting how well someone will remember what's studied and predicting who will benefit most from memory training.

Matzen presented the results of the first part of the study in April at the Cognitive Neuroscience Society conference in Chicago. She presented preliminary findings on the second part this summer to the Cognitive Science and Technology External Advisory Board, made up of representatives of universities, industry and laboratories who advise the investment area team managing the LDRD portfolio.

The second part tested different types of memory training to see how they changed participants' memory performance and brain activity. One of Matzen's goals is to find out whether recording a person's brain activity while they use their natural approach to studying can predict what kind of training would work best for that person.

She's still analyzing those findings, but said preliminary results are encouraging. The computer model from the earlier study was used to predict who would perform best on the memory tasks, and the high performers did even better after memory training.

"That's promising because one of the things we want to do is see if we can use the brain activity to predict how people react to the training, whether it will be effective for them," Matzen said.

A next step would be "to use more real-world memory working tasks, such as what military personnel would have to learn as new recruits, and see if the same patterns apply to more complex types of learning," she said.

About 90 volunteers spent nine to 16 hours over five weeks in testing for the memory training techniques study. Their first session developed a baseline for how well they remembered words or images. Most then underwent memory training for three weeks and were retested.

A control group received no training. A second group practiced mental imagery strategy, thinking up vivid images to remember words and pictures. The final group went through "working memory" training to increase how much information they could handle at a time. Matzen said that averages about seven items, such as digits in a phone number.

Each volunteer, shut into a sound-proof booth, watched a screen that flashed words or images for one second, interrupted with periodic quizzes on how well the person remembered what was shown.

"It's designed to be really difficult because we want lots of room to improve after memory training," Matzen said. The test was divided into five sections, each about 20 minutes long followed by a break to keep volunteers alert.

Each section tested a different type of memory. The first, middle and last sections consisted of single nouns. During quizzes, volunteers hit buttons for yes or no, indicating whether they'd seen the word before. The other two sections combined adjectives and nouns or pairs of unrelated drawings, with volunteers again tested on what they remembered. The image section tested associative memory -- memory for two unrelated things. Matzen said that's the most difficult because it links arbitrary relationships.

When performance was compared before and after training, the control group did not change, but the mental imagery group's performance improved on three of the five tasks.

"Imagery is a really powerful strategy for grouping things and making them more memorable," Matzen said.

The working memory group did worse on four of the five tasks after training.

Volunteers trained on working memory -- remembering information for brief periods -- improved on the task they'd trained on, but training did not carry over to other tasks, Matzen said.

She believes it boils down to strategy: The imagery training group learned a strategy, while working memory training simply tried to push the limits of memory capacity.

While the imagery group did better overall, they made more mistakes than the other groups when tested on "lures" that were similar, but not the same, as items they had memorized.

"They study things like 'strong adhesive' and 'secret password,' and then I might test them on 'strong password,' which they didn't see, but they saw both parts of it," Matzen said. "The people who have done the imagery training make many more mistakes on the recombinations that keep the same concept. If something kind of fits with their mental image they'll say yes to it even if it's not quite what they saw before."

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19 Sep, 2012

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Out of this world nanoscience: A computer chip that can assemble itself?

ScienceDaily (Sep. 19, 2012) — Imagine a computer chip that can assemble itself. According to Eric M. Furst, professor of chemical and biomolecular engineering at the University of Delaware, engineers and scientists are closer to making this and other scalable forms of nanotechnology a reality as a result of new milestones in using nanoparticles as building blocks in functional materials.

Furst and his postdoctoral researchers, James Swan and Paula Vasquez, along with colleagues at NASA, the European Space Agency, Zin Technologies and Lehigh University, reported the finding Sept. 17 in an article in the Proceedings of the National Academy of Sciences (PNAS) online edition.

The article details how the research team's exploration of colloids, microscopic particles that are mere hundredths the diameter of a human hair, to better understand how nano-"building blocks" can be directed to "self-assemble" into specific structures.

The research team studied paramagnetic colloids while periodically applying an external magnetic field at different intervals. With just the right frequency and field strength, the team was able to watch the particles transition from a random, solid like material into highly organized crystalline structures or lattices.

According to Furst, a professor in UD's Department of Chemical and Biomolecular Engineering, no one before has ever witnessed this guided "phase separation" of particles.

"This development is exciting because it provides insight into how researchers can build organized structures, crystals of particles, using directing fields and it may prompt new discoveries into how we can get materials to organize themselves," Furst said.

Because gravity plays a role in how the particles assemble or disassemble, the research team studied the suspensions aboard the International Space Station (ISS) through collaborative efforts with NASA scientists and astronauts. One interesting observation, Furst reported, was how the structure formed by the particles slowly coarsened, then rapidly grew and separated -- similar to the way oil and water separate when combined -- before realigning into a crystalline structure.

Already, Furst's lab has created novel nanomaterials for use in optical communications materials and thermal barrier coatings. This new detail, along with other recorded data about the process, will now enable scientists to discover other paths to manipulate and create new nanomaterials from nanoparticle building blocks.

"Now, when we have a particle that responds to an electric field, we can use these principles to guide that assembly into structures with useful properties, such as in photonics," Furst added.

The work could potentially prove important in manufacturing, where the ability to pre-program and direct the self-assembly of functional materials is highly desired.

"This is the first time we've presented the relationship between an initially disordered structure and a highly organized one and at least one of the paths between the two. We're excited because we believe the concept of directed self-assembly will enable a scalable form of nanotechnology," he said.

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The above story is reprinted from materials provided by University of Delaware. The original article was written by Karen B. Roberts.

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Journal Reference:

1. J. W. Swan, P. A. Vasquez, P. A. Whitson, E. M. Fincke, K. Wakata, S. H. Magnus, F. D. Winne, M. R. Barratt, J. H. Agui, R. D. Green, N. R. Hall, D. Y. Bohman, C. T. Bunnell, A. P. Gast, E. M. Furst. Multi-scale kinetics of a field-directed colloidal phase transition. Proceedings of the National Academy of Sciences, 2012; DOI: 10.1073/pnas.1206915109

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19 Sep, 2012

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University students put off-the-shelf helicopters to work

ScienceDaily (Sep. 18, 2012) — What amounts to serious scientific research could, at first glance, be mistaken for students at The University of Alabama in Huntsville letting off a little stress with radio-controlled helicopters.

On a recent sunny, humid day, the air near the university's Optics Building is filled with the buzz of small helicopters hovering over parking lots, their tiny video cameras sending back amazingly clear images of a wide expanse of ground below.

It's all part of work being done by UAHuntsville's Systems Management and Production Center at Von Braun Research Hall. Directed by Dr. Gary Maddux, SMAP is the largest of UAHuntsville's 15 research centers.

Under the program, several UAHuntsville students are working to develop micro-UAVs that could provide low-cost surveillance while enhancing the variety of uses for these UAVs. The U.S. Army's Aviation and Missile Research and Development Center (AMRDEC) on Redstone Arsenal provided the original program funding.

William Sabados and Norven Goddard direct a small cluster of students working to enhance the use of small, commercial, off-the-shelf helicopters to be more useful for both military and commercial purposes.

While the research is conducted at UAHuntsville and most student researchers are pursuing various UAHuntsville technical degrees, students from other north Alabama universities, and even a few from area high schools, have gravitated towards the program, said Sabados, who pairs students with research projects.

Those students span a wide range of technology curricula, from computer science and software engineering majors to aerospace, mechanical, and electrical engineering majors. Even graphics majors are getting involved, which Goddard said adds an important dimension to the work of the student teams.

"They have the ability to put it on paper and see how the design actually flows together. Visual is the way to go," Goddard said.

Terming the high level of technological capabilities of the student researchers "a state asset," Goddard said he hopes most of the graduates will find employment for their skills and talents right here in Alabama.

Goddard, of the Space and Missile Defense Command's Future Warfare Center, calls the program a resource that allows the military and first responders to tap the skills and abilities of students.

Their research supports the ongoing evolution of military intelligence, surveillance, and reconnaissance (ISR). ISR platforms are getting smaller and less costly, important in an era of increasing constraints on military R&D budgets. At altitudes of just a few hundred feet, they can peer down on enemy troops below while remaining practically invisible. Tighter budgets and the need to capture the benefits of emerging technologies also push the desire for what Goddard terms "the 80 percent solution."

"We want to take these emerging technologies and apply them where we can get a 70 to 80 percent solution that we can use right now." From a military standpoint, he said this eliminates some of the need for costly R&D programs that might develop a technology to a complete solution, only to have that technology become obsolete by the time that solution is achieved.

Sabados explained that "disruptive technologies" such as mini-UAVs have the potential to change the way surveillance is done, both for soldiers in theater and for first responders or law enforcement authorities.

Today's mini-UAVs, Sabados said, are the disruptive technology that larger UAVs used to be. "Ten years ago, UAVs were considered a disruptive technology, but now you see them on the news every night," he said.

Everything in aerial surveillance is getting smaller, lighter and less expensive. The mini-copters often carry tiny cameras that are marvels of miniaturization. Student researcher Aaron Laney holds out a camera currently being used that's about the size of a stack of three dominoes, and said the trend is for them to get ever smaller.

And while the military benefits are obvious, law enforcement and first responders are showing increasing interest in the tiny aerial platforms with their advanced cameras and other sensors. First responders could use them for low-cost surveying of post-tornado damage, or to survey the scene after a bad auto accident. Law enforcement sees uses ranging from looking for fugitives to find missing persons such as small children.

While military and civilian uses drive the research, Goddard also points to the influence of hobbyists, ranging from college students to retired engineers, who continue to push the envelope of new innovation. "The hobbyists have turned the game on the UAV community," he said. "They've pushed so hard on the designer and manufacturer community that they're producing components that are equal to those of large UAVs such as the Predator. The capabilities are becoming truly astronomical."

Student researcher and computer science major Aaron Laney comments on a video of a six-rotor mini-copter flying over a UAHuntsville parking lot. The team, he said, is now able to program a GPS chip that allows the mini-copters to fly a semi-autonomous flight pattern. "You just punch a few keys and tell them to fly the mission."

Goddard predicts a near future capability that will allow re-programming the GPS for totally autonomous flight of a swarm of several helicopters flying in close formation. "What you would do is program, launch, and walk away," he quipped.

That "swarm" of several helicopters are to fly in close formation. Each helicopter would carry a different sensor, allowing observers on the ground to get better overall situational awareness of what's on the ground that they could not otherwise see.

Another push is for low-cost production. The confluence of UAV miniaturization and low-cost, three-dimensional printing may allow for parts to be designed using computer-aided design programs, then instantly manufactured using 3D printers, according to Goddard. He said the original program, nearing completion, has been quite successful with ideas emerging that will give new students new programs to explore.

The experience from the research activities can look good on a resume, said Goddard. "It gives them the practical experience to go along with classroom theory," he said. "They'll have something to put on their resumes that will put them miles ahead of other graduating students."

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18 Sep, 2012

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Compound found in purple corn may aid in developing future treatments for type 2 diabetes, kidney disease

ScienceDaily (Sep. 18, 2012) — Diabetic nephropathy is one of the most serious complications related to diabetes, often leading to end-stage kidney disease. Purple corn grown in Peru and Chile is a relative of blue corn, which is readily available in the U.S. The maize is rich in anthocyanins (also known as flavonoids), which are reported to have anti-diabetic properties.

Scientists from the Department of Food and Nutrition and Department of Biochemistry at Hallym University in Korea investigated the cellular and molecular activity of purple corn anthocyanins (PCA) to determine whether and how it affects the development of diabetic nephropathy (DN). Their findings suggest that PCA inhibits multiple pathways involved in the development of DN, which may help in developing therapies aimed at type 2 diabetes and kidney disease.

The study is entitled "Purple corn anthocyanins inhibit diabetes-associated glomerular monocyte activation and macrophage infiltration." It appears in the online edition of the American Journal of Physiology -- Renal Physiology, published by the American Physiological Society.

Methodology

Researcher Min-Kyung Kang and colleagues performed a two-part study, an in vitro experiment investigating the effects of PCA on human endothelial cells cultured under hyperglycemic kidney conditions and an in vivo study that investigated the effects of PCA on kidney tissue in diabetic mice. In the in vitro experiment, cultured cells were exposed to 1-20 µg/ml of PCA for six hours (control cells were not exposed), then assessed for level of monocyte-endothelial cell adhesion, a major factor in the development of diabetic glomerulosclerosis. In the in vivo experiment, diabetic and control mice were dosed with PCA for eight weeks, then changes in kidney tissue were assessed and immunohistological analyses were performed. Kidney tissue was further analyzed for levels of inflammatory chemokines, which are key components in DN.

Results

Researchers found that in human endothelial cells cultured in hyperglycemic kidney conditions, induction of endothelial cell adhesion molecules decreased in a dose-dependent manner with PCA exposure, meaning that the PCA likely interfered with cell-cell adhesion in glomeruli. PCA also appeared to interfere with leukocyte recruitment and adhesion to glomerular endothelial cells. In diabetic mice, PCA exposure slowed mesangial expansion and interrupted the cellular signaling pathway that may instigate glomerular adhesion and infiltration of inflammatory cells responsible for diabetic glomerulosclerosis. Finally, PCA inhibited levels of macrophage inflammatory protein-2 and monocyte chemotactic protein-1 in kidney tissue, demonstrating that it may inhibit macrophage infiltration, which is closely related to renal inflammation.

Importance of the Findings

The research suggests that anthocyanins may be the main biofunctional compound in purple corn and could protect against mesangial activation of monocytes and infiltration of macrophages in glomeruli -- the two major contributors to DN. The research further suggests that renoprotection by PCA against mesangial activation may be specific therapies targeting diabetes-associated diabetic glomerulosclerosis and renal inflammation. Finally, PCA supplementation may be an important strategy in preventing renal vascular disease in type 2 diabetes.

"PCA may be a potential renoprotective agent treating diabetes-associated glomerulosclerosis," wrote the researchers.

Research Team

In addition to Min-Kyung Kang, the study team included Jing Li, Ju-Hyun Gong, Su-Nam Kwak, Jung Han Yoon Park, Soon Sung Lim and Young-Hee Kang, all also of the Department of Food and Nutrition at Hallym University in Korea, and Jae-Yong Lee, of the Department of Biochemistry at Hallym University.

Funding

This study was funded by a grant from the Ministry of Food, Agriculture, Forestry and Fisheries through Korea Institute of Planning and Evaluation for Technology of Food, Agriculture, Forestry and Fisheries; and by the National Research Foundation of Korea.

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The above story is reprinted from materials provided by American Physiological Society (APS).

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Journal Reference:

1. M.-K. Kang, J. Li, J.-L. Kim, J.-H. Gong, S.-N. Kwak, J. H. Y. Park, J.-Y. Lee, S. S. Lim, Y.-H. Kang. Purple corn anthocyanins inhibit diabetes-associated glomerular monocyte activation and macrophage infiltration. AJP: Renal Physiology, 2012; DOI: 10.1152/ajprenal.00106.2012

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Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

19 Sep, 2012

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Source: http://feeds.sciencedaily.com/~r/sciencedaily/strange_science/~3/Yp-PtOFU4gs/120918184756.htm
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Jesus's wife? Scholar announces existence of a new early Christian gospel from Egypt

ScienceDaily (Sep. 18, 2012) — Four words on a previously unknown papyrus fragment provide the first evidence that some early Christians believed Jesus had been married, Harvard Professor Karen King told the 10th International Congress of Coptic Studies today.

King, the Hollis Professor of Divinity at Harvard Divinity School, announced the existence of the ancient text at the Congress's meeting, held every four years and hosted this year by the Vatican's Institutum Patristicum Augustinianum in Rome. The four words that appear on the fragment translate to, "Jesus said to them, my wife." The words, written in Coptic, a language of ancient Egyptian Christians, are on a papyrus fragment of about one and a half inches by three inches.

"Christian tradition has long held that Jesus was not married, even though no reliable historical evidence exists to support that claim," King said. "This new gospel doesn't prove that Jesus was married, but it tells us that the whole question only came up as part of vociferous debates about sexuality and marriage. From the very beginning, Christians disagreed about whether it was better not to marry, but it was over a century after Jesus's death before they began appealing to Jesus's marital status to support their positions."

Roger Bagnall, director of the Institute for the Study of the Ancient World in New York, believes the fragment to be authentic based on examination of the papyrus and the handwriting, and Ariel Shisha-Halevy, a Coptic expert at Hebrew University in Jerusalem, considers it likely to be authentic on the basis of language and grammar, King said. Final judgment on the fragment, King said, depends on further examination by colleagues and further testing, especially of the chemical composition of the ink.

One side of the fragment contains eight incomplete lines of handwriting, while the other side is badly damaged and the ink so faded that only three words and a few individual letters are still visible, even with infrared photography and computer photo enhancement. Despite its tiny size and poor condition, King said, the fragment provides tantalizing glimpses into issues about family, discipleship, and marriage that concerned ancient Christians.

King and colleague AnneMarie Luijendijk, an associate professor of religion at Princeton University, believe that the fragment is part of a newly discovered gospel. Their analysis of the fragment is scheduled for publication in the January 2013 issue of Harvard Theological Review, a peer-reviewed journal.

King has posted a draft of the paper, an extensive question-and-answer on the fragment and its meaning, and images of it, on a page on the Divinity School website.

The brownish-yellow, tattered fragment belongs to an anonymous private collector who contacted King to help translate and analyze it. The collector provided King with a letter from the early 1980s indicating that Professor Gerhard Fecht from the faculty of Egyptology at the Free University in Berlin believed it to be evidence for a possible marriage of Jesus.

King said that when the owner first contacted her about the papyrus, in 2010, "I didn't believe it was authentic and told him I wasn't interested." But the owner was persistent, so in December 2011, King invited him to bring it to her at Harvard. After examining it, in March 2012 King carried the fragment to New York and, together with Luijendijk, took it to Bagnall to be authenticated. When Bagnall's examination of the handwriting, ways that the ink had penetrated and interacted with the papyrus, and other factors, confirmed its likely authenticity, work on the analysis and interpretation of the fragment began in earnest, King said.

Little is known about the discovery of the fragment, but it is believed to have come from Egypt because it is written in Coptic, the form of the Egyptian language used by Christians there during the Roman imperial period. Luijendijk suggested that "a fragment this damaged probably came from an ancient garbage heap like all of the earliest scraps of the New Testament." Since there is writing on both sides of the fragment, it clearly belongs to an ancient book, or codex, not a scroll, she said.

The gospel of which the fragment is but a small part, which King and Luijendijk have named the Gospel of Jesus's Wife for reference purposes, was probably originally written in Greek, the two professors said, and only later translated into Coptic for use among congregations of Coptic-speaking Christians. King dated the time it was written to the second half of the second century because it shows close connections to other newly discovered gospels written at that time, especially the Gospel of Thomas, the Gospel of Mary, and the Gospel of Philip.

Like those gospels, it was probably ascribed to one or more of Jesus's closest followers, but the actual author would have remained unknown even if more of it had survived. As it stands, the remaining piece is too small to tell us anything more about who may have composed, read, or circulated the new gospel, King said.

The main topic of the dialogue between Jesus and his disciples is one that deeply concerned early Christians, who were asked to put loyalty to Jesus before their natal families, as the New Testament gospels show. Christians were talking about themselves as a family, with God the father, his son Jesus, and members as brothers and sisters. Twice in the tiny fragment, Jesus speaks of his mother and once of his wife -- one of whom is identified as "Mary." The disciples discuss whether Mary is worthy, and Jesus states that "she can be my disciple." Although less clear, it may be that by portraying Jesus as married, the Gospel of Jesus's Wife conveys a positive theological message about marriage and sexuality, perhaps similar to the Gospel of Philip's view that pure marriage can be an image of divine unity and creativity.

From the very beginning, Christians disagreed about whether they should marry or be celibate. But, King notes, it was not until around 200 that there is the earliest extant claim that Jesus did not marry, recorded by Clement of Alexandria. He wrote of Christians who claimed that marriage is fornication instituted by the devil, and says people should emulate Jesus in not marrying, King said. A decade or two later, she said, Tertullian of Carthage in North Africa declared that Jesus was "entirely unmarried," and Christians should aim for a similar condition. Yet Tertullian did not condemn sexual relations altogether, allowing for one marriage, although he denounced not only divorce, but even remarriage for widows and widowers as overindulgence. Nearly a century earlier, the New Testament letter of 1 Timothy had warned that people who forbid marriage are following the "doctrines of demons," although it didn't claim Jesus was married to support that point.

In the end, the view that dominated would claim celibacy as the highest form of Christian sexual virtue, while conceding marriage for the sake of reproduction alone. The Gospel of Jesus's Wife, if it was originally written in the late second century, suggests that the whole question of Jesus's marital status only came up over a century after Jesus died as part of vociferous debates about sexuality and marriage, King said. King noted that contemporary debates over celibate clergy, the roles of women, sexuality, and marriage demonstrate that the issues are far from resolved.

"The discovery of this new gospel," King said, "offers an occasion to rethink what we thought we knew by asking what role claims about Jesus's marital status played historically in early Christian controversies over marriage, celibacy, and family. Christian tradition preserved only those voices that claimed Jesus never married. The Gospel of Jesus's Wife now shows that some Christians thought otherwise."

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The above story is reprinted from materials provided by Harvard Divinity School. The original article was written by B. D. Colen, Harvard News Office.

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19 Sep, 2012

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Source: http://feeds.sciencedaily.com/~r/sciencedaily/strange_science/~3/869ysAwmt8A/120918163643.htm
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How life arose on Earth: Researchers brew up organics on ice

ScienceDaily (Sep. 18, 2012) — Would you like icy organics with that? Maybe not in your coffee, but researchers at NASA's Jet Propulsion Laboratory in Pasadena, Calif., are creating concoctions of organics, or carbon-bearing molecules, on ice in the lab, then zapping them with lasers. Their goal: to better understand how life arose on Earth.

In a new study published in the Astrophysical Journal Letters, the research team provides the first direct look at the organic chemistry that takes place on icy particles in the frigid reaches of our solar system, and in the even chillier places between stars. Scientists think that the basic ingredients of life, including water and organics, began their journey to Earth on these lonesome ice particles. The ice and organics would have found their way into comets and asteroids, which then fell to Earth, delivering "prebiotic" ingredients that could have jump-started life.

The various steps needed to go from icy organics to slime molds are not clear, but the new findings help explain how the process works. The lab experiments show that organic material can begin the processing it needs to become prebiotic -- while still frozen in ice.

"The very basic steps needed for the evolution of life may have started in the coldest regions of our universe," said Murthy Gudipati, lead author of the new study at JPL. "We were surprised to see organic chemistry brewing up on ice, at these very cold temperatures in our lab."

The organics looked at in the study are called polycyclic aromatic hydrocarbons, or PAHs for short. These carbon-rich molecules can be found on Earth as combustion products: for example, in barbecue pits, candle soot and even streaming out of the tail pipe of your car. They have also been spotted throughout space in comets, asteroids and more distant objects. NASA's Spitzer Space Telescope has detected PAHs in the swirling planet-forming disks around stars, in the spaces between stars and in remote galaxies.

Murthy and his colleague Rui Yang of JPL used their lab setup to mimic the environment of icy PAH molecules in the quiet cold of space, at temperatures as low as 5 Kelvin (minus 450 degrees Fahrenheit, or minus 268 degrees Celsius). First, they bombarded the particles with ultraviolet radiation similar to that from stars. Then, to determine the products of the chemical reaction, they used a type of laser system known as MALDI (for Matrix Assisted Laser Desorption and Ionization), which involves zapping the ice with both infrared and ultraviolet lasers.

The results revealed that the PAHs had transformed: they had incorporated hydrogen atoms into their structure and lost their circular, aromatic bonds, becoming more complex organics. According to Gudipati, this is the type of change that would need to occur if the material were to eventually become amino acids and nucleotides -- bits and pieces of protein and DNA, respectively.

"PAHs are strong, stubborn molecules, so we were surprised to see them undergoing these chemical changes at such freezing-cold temperatures," said Gudipati.

Another bonus for the research is that it might explain the mystery of why PAHs have not yet been identified on ice grains in space. While the hardy organics are pervasive in the cosmos as gases and hot dust, researchers have remained puzzled that their signatures do not show up on ice. The new findings show that PAHs, once they stick to the ice surface, are chemically transformed into other complex organics, explaining why they might not be seen.

While the new results teach us that life's journey could have already begun in the very cold regions of the universe, another question remains: Did it arise elsewhere beyond our sun, too? Researchers don't know, but studies like this one help the ongoing search for life beyond Earth.

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Journal Reference:

1. Murthy S. Gudipati, Rui Yang. In-Situ Probing of Radiation-Induced Processing of Organics in Astrophysical Ice Analogs—novel Laser Desorption Laser Ionization Time-Of-Flight Mass Spectroscopic Studies. The Astrophysical Journal, 2012; 756 (1): L24 DOI: 10.1088/2041-8205/756/1/L24

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19 Sep, 2012

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Source: http://feeds.sciencedaily.com/~r/sciencedaily/strange_science/~3/8Whqt7ciLhw/120918162220.htm
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