Thursday, April 8, 2010

STUDY SAYS MONEY ONLY MAKES YOU HAPPY IF IT MAKES YOU RICHER THAN YOUR NEIGHBOURS

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A study by researchers at the University of Warwick and Cardiff University has found that money only makes people happier if it improves their social rank. The researchers found that simply being highly paid wasn’t enough – to be happy, people must perceive themselves as being more highly paid than their friends and work colleagues.

The researchers were seeking to explain why people in rich nations have not become any happier on average over the last 40 years even though economic growth has led to substantial increases in average incomes.

Lead researcher on the paper Chris Boyce from the University of Warwick’s Department of Psychology said:

“Our study found that the ranked position of an individual’s income best predicted general life satisfaction, while the actual amount of income and the average income of others appear to have no significant effect. Earning a million pounds a year appears to be not enough to make you happy if you know your friends all earn 2 million a year”

The study entitled “Money and Happiness: Rank of Income, Not Income, Affects Life Satisfaction” will be published in the journal Psychological Science. The researchers looked at data on earnings and life satisfaction from seven years of the British Household Panel Survey (BHPS), which is a representative longitudinal sample of British households.

First they examined how life satisfaction was related to how much money each person earned. They found however that satisfaction was much more strongly related to the ranked position of the person’s income (compared to people of the same gender, age, level of education, or from the same geographical area).

The results explain why making everybody in society richer will not necessarily increase overall happiness – because it is only having a higher income than other people that matters.

University of Warwick

GOOD VIBRATIONS

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Energy harvesting – using vibrations from the environment to produce electricity – has been around for over a decade, but Dr Stephen Burrow and his team in the Department of Aerospace Engineering hope that within five years it could be powering devices such as heart monitors and mobile phones. Currently the team is exploring how vibrations caused by machines such as helicopters and trains could be used to produce power, but vibrations from household appliances and the movement of the human body could also be harnessed for this purpose.

“Vibration energy-harvesting devices use a spring with a mass on the end,” explains Burrow. “The mass and spring exploit a phenomenon called resonance – the production of a large vibration in one object as a direct result of a relatively small vibration in another object – to amplify small vibrations, enabling useful energy to be extracted. Even just a few milliwatts can power small electronic devices like a heart rate monitor or an engine temperature sensor, but it can also be used to recharge power-hungry devices like MP3 players or mobile phones.”

Existing devices can only exploit vibrations that have a narrow range of frequencies, so if the vibrations don’t occur at the right frequency, very little power can be produced. This is a big problem in applications like transport or human movement where the frequency of vibrations changes all the time.

The Bristol team is therefore developing a new device where the mass and spring resonate over a much wider range of frequencies. This would enable a much wider range of vibrations to be exploited and so increase the overall contribution that energy harvesting could make to energy supplies. The team believes it can achieve this by exploiting the properties of non-linear springs which allow the energy harvester to respond to a wider range of vibration frequencies.

Energy harvesters generate low-level power on a similar scale to batteries but without the need for battery replacement or disposal of potentially dangerous and polluting chemicals. They are also suited to applications where hard-wiring would be impracticable, vulnerable to damage, or difficult to access for maintenance purposes.

“There’s a huge amount of free, clean energy out there in the form of vibrations that just can’t be tapped at the moment,” says Burrow. “Wider-frequency energy harvesters could make a valuable contribution to meeting our energy needs more efficiently and sustainably.”

(Photo: Bristol U.)

University of Bristol

MAPPING VENUS

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Venus and Earth have long been thought of as sister planets. Given its similar size and proximity to Earth in the inner Solar System, Venus might seem like a promising candidate for having a surface that evolves through a tectonic process similar to what occurs on Earth, where rigid plates slowly shift across the underlying mantle.

But a recent analysis by Peter James, a graduate student in the Department of Earth, Atmospheric and Planetary Sciences, highlights the fact that Earth’s plate tectonics seem to be the exception rather than the rule for rocky planets like Venus, Mars and Mercury.

James provides new evidence that the generation and recycling of the surface on Venus occurs through a process that is actually quite different from what happens on Earth. His finding supports a theory that first arose in the early 1990s, when NASA’s Magellan spacecraft orbited Venus and took radar images of the planet’s surface. Before Magellan, most scientists assumed that the surface of Venus was influenced by some form of plate tectonics or volcanism.

The Magellan images revealed a distribution of craters that suggest that most of Venus’ surface was formed around the same time — about 500 million years ago, which is young considering that the planet’s age is estimated at about 4.6 billion years. As a result of this uniform age of the surface, scientists hypothesized that the Venus surface is not made of moving plates like Earth, nor is it inactive like the moon. Instead it evolves through a periodic resurfacing process, possibly caused by volcanic activity.

Geologists study features of a planet’s crust, such as its thickness and composition, for clues about that planet’s history. These clues shed light on the physical processes that made the crust, which is usually produced by partial melting of mantle material.

To study Venus’ crust, James used gravity and topography data collected by Magellan between 1990 and 1994. Analyzing these data, James mapped the thickness of the planet’s crust, which he calculated to be about 30 kilometers (Earth’s is about 20 kilometers, on average). He could identify regions where Venus’ convecting mantle is pushing or pulling on its crust as the planet cools.

While these results provide a better picture of the Venus crust, what is most compelling about the analysis, which James presented on March 1 at the Lunar and Planetary Science Conference, is the discovery that there are no large mass concentrations, or “mascons,” buried beneath the surface of Venus.

Existing on Mars and the moon, mascons are gravity anomalies that correspond to large craters and basins created billions of years ago by massive impacts from large meteoroids. These mascons exert a slightly stronger gravitational pull — detected by spacecraft or satellites — than that of a smooth surface. While the process of mascon formation is not well understood, James explained that the extra gravitational pull likely comes from two sources: dense rock in the craters from volcanic flow and the placement of denser mantle material near the surface.

James expected to find remnants of these crustal structures on Venus, given that they are prominent features on Mars and the moon. He believes that the absence of mascons is consistent with the idea that the Venus surface experienced some sort of “catastrophic overturning” at least 500 million years ago. “If the mascons were erased in the event 500 million years ago, that would require a mechanism that more thoroughly reworks the crust,” he explained.

Brown University geologist Marc Parmentier agreed with James that the lack of mascons indicates that some sort of mechanism — perhaps large-scale volcanic activity — periodically creates a new surface on Venus.

He praised the analysis for ensuring that research about Venus remains an active area in planetary science, which is currently heavily focused on Mars and the moon. “His work lets us continue to address one of the questions of Venus, which is how this so-called resurfacing process took place,” he said.

James hopes to address this question in future research by using more finite element modeling to understand how mascons are formed and evolve. He said that NASA’s upcoming GRAIL mission to the moon will gather unprecedented gravity data that will provide some basis for comparing the lunar and Venus crusts.

(Photo: NASA Jet Propulsion Laboratory)

MIT

ROASTING BIOMASS MAY BE KEY PROCESS IN BIOENERGY ECONOMY

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Biorefineries may soon rely on a process akin to roasting coffee beans to get more energy-dense biomass.

A new collaborative study between Idaho National Laboratory and Pacific Northwest National Laboratory (PNNL) will investigate whether such roasting can create a more valuable product for the nascent biofuels industry. Initial studies show that driving moisture and volatile compounds from wood or straw could make the biomass more stable, compactable and energy dense.

"This could cut a lot of costs by providing a less expensive and higher-value product," said INL biofuels researcher Christopher Wright. "This technology has the ability to overcome biomass's moisture, mass and energy density problems, which make up a huge proportion of the cost barriers."

The technology he refers to is called "torrefaction" — heating biomass above 250 degrees Celsius in an oxygen-free environment. "It's not very different from roasting coffee beans," said Wright. But while coffee beans are roasted for flavor, biomass could be "torrefied" simply to improve its physical characteristics.

Two characteristics that heavily influence the logistics and economics of today's biomass industry are moisture and density. Most biomass is wet, which complicates long-term storage; and it's not very dense, which compromises the cost efficiency of mass transportation. Driving out moisture and volatile compounds through this process could address both issues.

Torrefied biomass has almost no water and actually becomes water resistant, which could improve storage in humid climates. The torrefied product also breaks down more easily so it's more uniform after grinding.

With research funding from the U.S. Department of Energy's Office of the Biomass Program, INL researchers are now torrefying biomass to further study physical characteristics of the dried product, its production cost and how much energy it could generate.

For example, they want to know whether the deeply dried biomass is easier to compact into pellets or briquettes. The energy used in the torrefaction process and the resulting energy content of the torrefied biomass needs to be measured to determine production costs. Collaborators at PNNL led by researcher Doug Elliott's team will study whether the torrefaction process improves the quality of the resulting biorefinery product.

"We want to understand if the properties of the torrefied biomass can improve the overall conversion of biomass into fuels," said Elliott.

INL recently shipped 30 kilograms of both raw and torrefied white oak to the PNNL team. Future shipments will include torrefied corn stover, wheat straw, switchgrass and two types of woody biomass.

Both research teams are eager to determine whether torrefaction can economically deliver a more stable, energy-dense feedstock that can be effectively converted into higher quality products at biorefineries. If so, the process could help cellulosic biomass compete as a nationally traded energy commodity.

"This may open access to more material," said Wright. "INL is looking at whether it's possible to create a homogeneous commodity product from biomass."

Idaho National Laboratory

COULD SMELL PLAY A ROLE IN THE ORIGIN OF NEW BIRD SPECIES?

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Two recently diverged populations of a southern California songbird produce unique odors, suggesting smell could contribute to the reproductive isolation that accompanies the origin of new bird species. The Indiana University Bloomington study of organic compounds present in the preen oils of Dark-eyed Juncos is described in this month's Behavioral Ecology.

"There's so much we don't know about the role of smell in bird behavior," said biologist Danielle Whittaker, the study's lead author. "Differences in smell could be affecting sexual behavior, parental care and even contribute to speciation."

Whittaker is a postdoctoral researcher in IU Bloomington biologist Ellen Ketterson's research group.

Led by Whittaker, a team of IU Bloomington biologists and chemists examined the chemical composition of preen oil, which is a compound birds secrete and spread around their bodies to straighten, protect and waterproof their feathers. To analyze the odor chemistry of preen oil, the scientists isolated 19 volatile molecules that can achieve a gaseous, more sniff-friendly state. The chemical isolation and analysis portion of the interdisciplinary project was led by IU Bloomington Department of Chemistry Distinguished Professor Milos Novotny and Senior Scientist Helena Soini.

The scientists found that each junco possesses a unique and recognizable odor profile that was stable over a two-week period and that could be used to distinguish it from other individuals. The odor profiles of male birds differed from those of female birds, and birds' odor profiles differed depending on which population they were from.

"This is the most comprehensive study of its kind," Whittaker said. "And as far as we know, it is the first time anyone has looked closely at these chemical compounds at the population level in any bird."

Last year, Whittaker, Ketterson, and others reported in the Journal of Avian Biology that juncos can use preen oils to distinguish members of their own species from other species, and between individuals of their own species. The present Behavioral Ecology study went a step further to see whether the chemical composition of preen oil varies among individuals, sexes and populations -- which might be meaningful in an evolutionary context.

The team collected juvenile juncos from two populations, one that resides in and around the University of California San Diego campus in La Jolla, Calif., and another that lives in the Laguna Mountains, about 42 miles east. After capture, the birds were transported to aviaries in Bloomington, Ind., and raised under identical environmental conditions. The scientists used gas chromatography-mass spectrometry to isolate 19 volatile compounds from the preen oils which are secreted from the birds' uropygial glands near the base of the tail.

The researchers confirmed that individual birds sampled over time produce levels of each of the volatile compounds that remain more or less constant. They also found gross differences between males and females, and between juncos from the UC San Diego population and birds from the mountains. These population differences were found even though the birds were raised in identical conditions, suggesting that the odors have a genetic, rather than an environmental or developmental basis.

The particular suite of 19 compounds is, as far as the scientists know, unique to juncos. However, this area of research is so new that odor chemistry profiles have been documented for only a few species. This field of research is growing rapidly as biologists realize the potential importance of scent in bird communication and evolution.

Until just a few years ago, most bird biologists believed that smell played little or no role in bird behavior. The olfactory bulb -- a portion of vertebrate brain known to interpret odors -- is small relative to birds' brain sizes. Birds also lack the vomeronasal organ that many mammals (and reptiles) use to sense pheromones specifically.

Then came the discovery that sea-faring petrels can smell so well that they can identify other birds through sense of smell alone. This discovery kicked off a re-examination of several bird species, and preliminary results suggest smell in birds is a behavioral cue that has been overlooked for far too long.

"We still don't know how common it is for birds to use smell," Whittaker said. "The evidence so far suggests there is much for us to learn."

(Photo: Jonathan Atwell)

Indiana University Bloomington

NEW THEORY OF DOWN SYNDROME CAUSE MAY LEAD TO NEW THERAPIES

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Conventional wisdom among scientists for years has suggested that because individuals with Down syndrome have an extra chromosome, the disorder most likely results from the presence of too many genes or proteins contained in that additional structure.

But a recent study reveals that just the opposite could be true – that a deficiency of a protein in the brain of Down syndrome patients could contribute to the cognitive impairment and congenital heart defects that characterize the syndrome.

Scientists have shown in a series of experiments that there are lower levels of this protein in the brains of humans and mice with Down syndrome than are present in humans and mice without the disorder.

The researchers also showed that manually manipulating pieces of RNA that regulate the protein could increase protein levels in both human cell lines and mouse brains. In fact, an experimental drug that acts on those RNA segments returned this protein to normal levels in mice that model the syndrome.

When this RNA segment is overexpressed – meaning that more of it is present than needed in a cell – the protein level goes down, or is underexpressed. A total of at least five of these RNA segments are naturally overexpressed in persons with Down syndrome because the segments are housed on chromosome 21 – the chromosome that causes the disorder.

“We’re talking about a paradigm-shifting idea that maybe we should look for underexpressed proteins and not overexpressed proteins in Down syndrome,” said Terry Elton, senior author of the study and a professor of pharmacology at Ohio State University.

“What this offers to the Down syndrome community is the potential for at least five new therapeutic targets to pursue.”

The Centers for Disease Control and Prevention estimates that about 13 of every 10,000 babies born in the United States each year have Down syndrome, characterized primarily by a mild-to-moderate range of intellectual disabilities, possible delayed language development and difficulties with physical coordination.

The study is published in a recent issue of the Journal of Biological Chemistry.

Elton, also interim director of Ohio State’s Davis Heart and Lung Research Institute, stumbled upon this theory about Down syndrome while working on a different protein associated with cardiovascular disease. It turns out the protein he has studied for 25 years was regulated by one of these microRNAs that is known to be housed on chromosome 21.

A key role of RNA in a cell is to make protein, and proteins are the building blocks of all life. But the process has many steps. MicroRNAs are small pieces of RNA that bind to messenger RNA, which contains the actual set of instructions for building proteins. When that connection is made, however, the microRNA inhibits the building of the protein. Why that occurs is not completely understood, but increasingly microRNAs are considered tiny molecules that have a big impact in a number of physiological processes.

For his cardiovascular disease research, Elton found that a genetic trait in some people caused one specific microRNA to be bad at its job, leading to high protein levels that contribute to cardiovascular disease. This malfunctioning molecule is called microRNA-155, or miR-155.

“So we became interested in miR-155, and it is on chromosome 21. That’s how we jumped to Down syndrome,” Elton said.

There is also a strong link between the heart and Down syndrome. About half of those with the syndrome are born with congenital heart defects – problems with the heart’s anatomy, not coronary arteries. But they do not experience cardiovascular disease or high blood pressure.

The advent of biomedical informatics has allowed scientists to use supercomputers to explore the human genome in a search for genes and their various relationships in the context of human disease. Elton consulted a bioinformatic database and found that five microRNAs sit on chromosome 21, and he and colleagues demonstrated in previous research that all five of them are overexpressed in the tissues, brains and hearts of Down syndrome patients.

“That means that whatever proteins these microRNAs work with are underexpressed,” Elton said.

Further database exploration suggested that these five microRNAs target 1,695 proteins, all of which could cause problems in Down syndrome because they are underexpressed. To narrow that to a more manageable number, Elton’s group had to make an educated guess based on a variety of data, including which proteins that are connected to these microRNAs are made by cells in the brain and heart – two areas most commonly affected by Down syndrome.

A protein surfaced as an attractive target to study: methyl-CpG-binding protein 2, known as MeCP2. Among the reasons it seemed important: A mutation in this protein is already known to lead to Rett syndrome, a cognitive disorder.

“So we thought that it was more than a coincidence that this protein plays a role in normal brain development, and if the protein doesn’t function right, you’re going to have cognitive impairment. Maybe this is the connection,” Elton said. “We still don’t know if this is the most important protein related to Down syndrome. But we were able to go on and prove scientifically that MeCP2 is a target of these microRNAs on chromosome 21.”

The researchers used just two of the five microRNAs on chromosome 21 for the experiments in this study, miR-155 and miR-802, to match the only microRNAs available in the genetically engineered mouse model of Down syndrome.

First, the researchers made copies of the relevant microRNAs. In human brain cell lines, they manipulated levels of those two molecules to show the inverse relationship with the protein. If the microRNAs were more active, the level of the MeCP2 protein went down. When the microRNAs were underexpressed, the protein levels went up.

Next, the researchers examined adult and fetal human brain tissue from healthy and Down syndrome samples obtained from a national tissue bank.

“In both adult and fetal Down syndrome brain samples, it didn’t matter which area of the brain we were looking at, the MeCP2 proteins were down. These are just observations with no manipulation on our part, and the MeCP2 is almost non-existent in the Down syndrome brain,” Elton said. “We marked the protein with a fluorescent molecule, and by comparison, we could visualize and appreciate how much MeCP2 was being made by neurons in the control samples.”

MeCP2 is a transcription factor, meaning it turns genes on and off. If its levels are too low in the brain, this suggests that genes influenced by its presence should be malfunctioning, too. Based on previous research by another group, Elton and colleagues focused on two genes affected by the MeCP2 protein for their next set of experiments.

Looking again at the human brain tissue samples, they found that the genes were indeed affected by the lowered protein level in Down syndrome brains – one gene that MeCP2 normally silences was in abundance, and the gene that should have been activated was underexpressed. Because the two genes examined have known roles in neural development, Elton said the results suggested even more strongly that the lowered protein’s effects on the genes likely contribute to cognitive problems associated with Down syndrome.

Finally, the researchers tested an experimental drug called an antagomir on mice that serve as models for Down syndrome research. Antagomirs are relatively new agents that render microRNAs inactive. The scientists injected an antagomir into the brains of these mice to silence the miR-155 with the intent to increase levels of the MeCP2 protein. Seven days after the injection, the level of the protein in the treated mouse brains resembled levels in normal mouse brains.

“We showed that we can fix the protein abnormality in mice that model Down syndrome. But we can’t undo the pathology that has already occurred,” Elton said. “It’s a starting point, but it appears that we have new therapeutic targets to consider.”

(Photo: OSU)

Ohio State University

HELIUM RAIN ON JUPITER EXPLAINS LACK OF NEON IN ATMOSPHERE

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On Earth, helium is a gas used to float balloons, as in the movie "Up." In the interior of Jupiter, however, conditions are so strange that, according to predictions by University of California, Berkeley, scientists, helium condenses into droplets and falls like rain.

Helium rain was earlier proposed to explain the excessive brightness of Saturn, a gas giant like Jupiter, but one-third the mass.

On Jupiter, however, UC Berkeley scientists claim that helium rain is the best way to explain the scarcity of neon in the outer layers of the planet, the solar system's largest. Neon dissolves in the helium raindrops and falls towards the deeper interior where it re-dissolves, depleting the upper layers of both elements, consistent with observations.

"Helium condenses initially as a mist in the upper layer, like a cloud, and as the droplets get larger, they fall toward the deeper interior," said UC Berkeley post-doctoral fellow Hugh Wilson, co-author of a report appearing this week in the journal Physical Review Letters. "Neon dissolves in the helium and falls with it. So our study links the observed missing neon in the atmosphere to another proposed process, helium rain."

Wilson's co-author, Burkhard Militzer, UC Berkeley assistant professor of earth and planetary science and of astronomy, noted that "rain" – the water droplets that fall on Earth – is an imperfect analogy to what happens in Jupiter's atmosphere. The helium droplets form about 10,000 to 13,000 kilometers (6,000-8,000 miles) below the tops of Jupiter's hydrogen clouds, under pressures and temperatures so high that "you can't tell if hydrogen and helium are a gas or a liquid," he said. They're all fluids, so the rain is really droplets of fluid helium mixed with neon falling through a fluid of metallic hydrogen.

The researchers' prediction will help refine models of Jupiter's interior and the interiors of other planets, according to Wilson. Modeling planetary interiors has become a hot research area since the discovery of hundreds of extrasolar planets living in extreme environments around other stars. The study will also be relevant for NASA’s Juno mission to Jupiter, which is scheduled to be launched next year.

Militzer and Wilson are among the modelers, using "density functional theory" to predict the properties of Jupiter's interior, specifically what happens to the dominant constituents – hydrogen and helium – as temperatures and pressures increase toward the center of the planet. These conditions are yet too extreme to be reproduced in the laboratory. Even experiments in diamond-anvil cells can only produce pressures at the Earth's core. In 2008, Militzer's computer simulations led to the conclusion that Jupiter's rocky core is surrounded by a thick layer of methane, water and ammonia ices that make it twice as large as earlier predictions.

The two modelers embarked on their current research because of a discovery by the Galileo probe that descended through Jupiter's atmosphere in 1995 and sent back measurements of temperature, pressure and elemental abundances until it was crushed under the weight of the atmosphere. All elements seemed to be as slightly enriched compared to the abundance on the sun – which is assumed to be similar to the elemental abundances 4.56 billion years ago when the solar system formed – except for helium and neon. Neon stood out because it was one-tenth as abundant as it is in the sun.

Their simulations showed that the only way neon could be removed from the upper atmosphere is to have it fall out with helium, since neon and helium mix easily, like alcohol and water. Militzer and Wilson's calculations suggest that at about 10,000 to 13,000 kilometers into the planet, where the temperature about 5,000 degrees Celsius and the pressure is 1 to 2 million times the atmospheric pressure on Earth, hydrogen turns into a conductive metal. Helium, not yet a metal, does not mix with metallic hydrogen, so it forms drops, like drops of oil in water.

This provided an explanation for the removal of neon from the upper atmosphere.

"As the helium and neon fall deeper into the planet, the remaining hydrogen-rich envelope is slowly depleted of both neon and helium," Militzer said. "The measured concentrations of both elements agree quantitatively with our calculations."

Saturn's helium rain was predicted because of a different observation: Saturn is warmer than it should be, based on its age and predicted rate of cooling. The falling rain releases heat that accounts for the difference.

Jupiter's temperature is in accord with models of its cooling rate and its age, and needed no hypothesis of helium rain until the discovery of neon depletion in the atmosphere. Interestingly, theoretician David Stevenson of the California Institute of Technology (Caltech) predicted neon depletion on Jupiter prior to the Galileo probe's measurements, but never published a reason for his guess.

(Photo: Burkhard Militzer)

University of California, Berkeley

FACIAL AGING IS MORE THAN SKIN DEEP

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Facelifts and other wrinkle-reducing procedures have long been sought by people wanting to ward off the signs of aging, but new research suggests that it takes more than tightening loose skin to restore a youthful look. A study by physicians at the University of Rochester Medical Center indicates that significant changes in facial bones – particularly the jaw bone – occur as people age and contribute to an aging appearance.

Presented at the American Association of Plastic Surgeons annual meeting in San Antonio, Texas, and published in the Journal of Plastic and Reconstructive Surgery, the study suggests that the future approach to facial rejuvenation may be two-fold, first restoring structure underneath before performing skin-tightening procedures.

Reviewing a collection of 120 facial CT scans taken for other, unrelated medical reasons, plastic surgeons measured changes that occurred to facial bones over time. The CT scans were divided equally by gender and age, 20 men and 20 women in each of three age groups: young (ages 20-36), middle (41 to 64), and old (65 and older). Researchers used a computer program to measure the length, width, and angle of the mandible, or jaw bone, for each scan, and compare the results for each group. Using CT scans for this study allowed for more accurate three-dimensional reconstruction and increased accuracy of measurements, disputing previous research that relied on traditional head x-rays and suggested that the jaw bone expands with age.

The angle of the jaw increases markedly with age, which results in a loss of definition of the lower border of the face, according to the study. Jaw length decreases significantly in comparisons between the young and middle age groups, whereas the decline in jaw height from the middle to old group was noteworthy.

“The jaw is the foundation of the lower face, and changes to it affect facial aesthetics,” said Howard N. Langstein, M.D., professor and chief of Plastic and Reconstructive Surgery at the University of Rochester Medical Center. “These measurements indicate a significant decline in the jaw’s volume as a person ages, and therefore less support of soft tissue of the lower face and neck.”

This loss of bony volume may contribute sagging facial skin, decreased chin projection, and loss of jaw-line definition. As jaw volume decreases, soft tissue of the lower face has less support, resulting in a softer, oval appearance to the lower face and sagging skin, which also affects the aging appearance of the neck.

“Physicians have long been taught that facial aging is caused by soft tissue descent and loss of elasticity,” Langstein said. “Though we have always known that bones change over time, until now, the extent to which it causes an aged appearance was not appreciated.”

The study by Langstein and plastic surgery resident Robert Shaw, M.D., gives evidence that facial bones are constantly subjected to forces that remodel them. Understanding there are predictable changes in facial bone structure as people age gives physicians new insight into procedures that may successfully restore youthful appearance. Shaw and Langstein led the three-institution collaboration, which also involved Stanford University and Harvard University.

“The future of facial cosmetic procedures to restore a youthful look may include methods to suspend soft tissue – such as chin and cheek implants – to rebuild the structure that time has worn away, in addition to lifting and reducing excess skin,” Shaw said.

(Photo: U. Rochester)

University of Rochester Medical Center

NEW DINOSAUR FROM UTAH'S RED ROCKS

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Utah's red rocks - world-famous attractions at numerous national parks, monuments and state parks - have yielded a rare skeleton of a new species of plant-eating dinosaur that lived 185 million years ago and may have been buried alive by a collapsing sand dune. The discovery confirms the widespread success of sauropodomorph dinosaurs during the Early Jurassic Period.

Until now, Utah's red rocks were known only for a few scattered bones and dinosaur footprints. However, discovery of a remarkably preserved partial skeleton has been published in the March 24 edition of PLoS ONE, the online open-access journal produced by the Public Library of Science.

The study was conducted by Joseph Sertich, a former University of Utah master's student and current Stony Brook University Ph.D. student, and Mark Loewen, a paleontologist at the Utah Museum of Natural History and instructor in the Department of Geology and Geophysics at the University of Utah.

The new dinosaur species is named Seitaad ruessi (SAY-eet-AWD ROO-ess-EYE), which is derived from the Navajo word, "Seit'aad," a sand-desert monster from the Navajo (Diné) creation legend that swallowed its victims in sand dunes (the skeleton of Seitaad had been "swallowed" in a fossilized sand dune when it was discovered); and Ruess, after the artist, poet, naturalist and explorer Everett Ruess who mysteriously disappeared in the red rock country of southern Utah in 1934 at age 20.

Seitaad ruessi is part of a group of dinosaurs known as sauropodomorphs. Sauropodomorphs were distributed across the globe during the Early Jurassic, when all of the continents were still together in the supercontinent named Pangaea. Millions of years later, sauropodomorphs evolved into gigantic sauropods, long-necked plant eaters whose fossils are well known from elsewhere in Utah, including Dinosaur National Monument.

The skeleton of Seitaad was discovered protruding from the multicolored cliffs of Navajo Sandstone in 2004 by local historian and artist, Joe Pachak, while hiking in the Comb Ridge area near Bluff, Utah. His discovery, located just below an ancestral Puebloan (Anasazi) cliff-dwelling, was subsequently reported to the federal Bureau of Land Management (BLM) and the Utah Museum of Natural History. Museum paleontologists and crews excavated and collected the specimen in 2005.

The beautifully preserved specimen includes most bones of the skeleton, except for the head, and parts of the neck and tail. Seitaad was found in fossilized sand dunes that were part of a vast desert that covered the region nearly 185 million years ago during the Jurassic Period. Research suggests that the animal was buried in a suddenly collapsing sand dune that engulfed the remains and stood them on their head. The missing parts of the skeleton were lost to erosion over the past thousand years, but were almost certainly visible when Native Americans lived on the cliff just above the skeleton.

In life, the animal would have stood about 3 to 4 feet (about 1 meter) tall at the hips and was 10 to 15 feet (3 to 4.5 meters) long. It would have weighed approximately 150 to 200 pounds (70 to 90 kilograms), and could walk on two or four legs. Like its later gigantic relatives, Seitaad most likely ate plants.

Early sauropodomorphs, including Seitaad, had long necks and tails with small heads and leaf-shaped teeth, suggesting that they were specialized for an herbivorous (plant-eating) diet. These same traits were carried on in their much larger descendents, the sauropods. "Although Seitaad was preserved in a sand dune, this ancient desert must have included wetter areas with enough plants to support these smaller dinosaurs and other animals," said Sertich. "Just like in deserts today, life would have been difficult in Utah's ancient 'sand sea.'"

According to Loewen, "We know from geologic evidence that seasonal rainstorms like today's summer monsoons provided much of the moisture in this sand sea filling ponds and other low spots between the sand dunes."

The closest relatives of Seitaad are known from similar-aged rocks in South America and southern Africa. Other, less complete, fossils from northern Arizona hinted at the presence of sauropodomorphs like Seitaad, but none were complete enough to understand exactly what species was living in the American Southwest. The discovery of Seitaad confirms that this group of dinosaurs was extremely widespread and successful during the Early Jurassic, approximately 175 million to 200 million years ago.

Although the Navajo Sandstone is exposed all over Utah and Arizona, fossils are extremely rare and we have not yet learned much about the animals that lived in this giant desert. Other animals that lived in the Navajo Sandstone were all relatively small animals, including a carnivorous dinosaur, crocodile relatives and proto-mammals called tritylodonts. Even though Seitaad was quite small, it was likely the largest herbivore during this time period in southern Utah. "This new find suggests that there may be more dinosaurs yet to be discovered in these rocks," said Sertich.

(Photo: Utah Museum of Natural History, the University of Utah)

University of Utah

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