Abortions Are Safe When Performed by Nurses Practitioners, Physician Assistants and Certified Nurse Midwives, Study Suggests

First trimester abortions are just as safe when performed by trained nurse practitioners, physician assistants and certified nurse midwives as when conducted by physicians, according to a new six-year study led by UCSF.

The study posted online January 18 in the American Journal of Public Health in advance of the print edition.

The publication comes a week before the 40th anniversary of the Roe vs. Wade, the landmark Supreme Court decision that made abortion legal in the United States.

Currently in the United States, a patchwork of state regulations determines who can provide abortions, with several states specifically prohibiting non-physician clinicians from performing the procedure.

The new study was designed to evaluate the safety of early aspiration abortions when performed by nurse practitioners, physician assistants and certified nurse midwives trained in the procedure. The study was conducted under a legal waiver from the Health Workforce Pilot Projects Program, a division of the California Office of Statewide Health Planning and Development. California law requires a legal clarification about who can perform aspiration abortions.

The researchers report in their study that the results show the pool of abortion providers could be safely expanded beyond physicians to include other trained health care professionals. They found that:

Nurse practitioners, certified nurse midwives and physician assistants can provide early abortion care that is clinically as safe as physicians;

Outpatient abortion is very safe, whether it is provided by physicians or by nurse practitioners, certified nurse midwives or physician assistants.

Nationally, 92 percent of abortions take place in the first trimester but studies find that black, uninsured and low-income women continue to have less access to this care, according to the researchers.

In California, 13 percent of women using state Medicaid insurance obtain abortions after the first trimester. Because the average cost of a second trimester abortion is substantially higher than a first trimester procedure and abortion complications increase as the pregnancy advances, shifting the population distribution of abortions to earlier gestations may result in safer, less costly care, according to the research team.

"Increasing the types of health care professionals who can provide early aspiration abortion care is one way to reduce this health care disparity,'' said lead author Tracy Weitz, PhD, MPA, a UCSF associate professor and director of Advancing New Standards in Reproductive Health at the UCSF Bixby Center for Global Reproductive Health. "Policy makers can now feel confident that expanding access to care in this way is evidence-based and will promote women's health.''

Currently, non-physicians are allowed to perform aspiration abortions in four states: Montana, Oregon, New Hampshire and Vermont. In other states, non-physician clinicians are permitted to perform medication but not aspiration abortions. In recent years, in an effort to limit abortion availability, several states have put laws on the books to prohibit non-physician clinicians from performing abortions.

In the study, 40 nurse practitioners, certified nurse midwives and physician assistants from four Planned Parenthood affiliates and from Kaiser Permanente of Northern California were trained to perform aspiration abortions. They were compared to a group of nearly 100 physicians, who had a mean of 14 years of experience providing abortions.

Altogether, 5,675 abortions were performed in the study by nurse practitioners, certified nurse midwives and physician assistants, compared to 5,812 abortions by physicians. The abortions were performed between August 2007 and August 2011 at 22 clinical facilities in California.

The researchers found that both groups of abortion providers had few complications -- less than 2 percent, including incomplete abortions, minor infection and pain. Statistically, according to the researchers, the complication rates were not different between the two groups of providers.

"The value of this study extends beyond the question of who can safely perform aspiration abortion services in California because it provides an example of how research can be used to answer relevant health care policy issues,'' said study co-author Diana Taylor, PhD, RNP, professor emeritus in the UCSF School of Nursing. "As the U.S. demand for cost-effective health care increases, workforce development has become a key component of health care reform. All qualified health professionals should perform clinical care to the fullest extent of their education and competency.''

The study was funded by grants from private foundations including the John Merck Foundation, the Educational Foundation of America, the David & Lucile Packard Foundation, and the Susan Thompson Buffet Foundation.

Link Between Quantum Physics and Game Theory Found

A deep link between two seemingly unconnected areas of modern science has been discovered by researchers from the Universities of Bristol and Geneva.

While research tends to become very specialized and entire communities of scientists can work on specific topics with only a little overlap between them, physicist Dr Nicolas Brunner and mathematician Professor Noah Linden worked together to uncover a deep and unexpected connection between their two fields of expertise: game theory and quantum physics.

Dr Brunner said: "Once in a while, connections are established between topics which seem, on the face of it, to have nothing in common. Such new links have potential to trigger significant progress and open entirely new avenues for research."

Game theory -- which is used today in a wide range of areas such as economics, social sciences, biology and philosophy -- gives a mathematical framework for describing a situation of conflict or cooperation between intelligent rational players. The central goal is to predict the outcome of the process. In the early 1950s, John Nash showed that the strategies adopted by the players form an equilibrium point (so-called Nash equilibrium) for which none of the players has any incentive to change strategy.

Quantum mechanics, the theory describing the physics of small objects such as particles and atoms, predicts a vast range of astonishing and often strikingly counter-intuitive phenomena, such as quantum nonlocality. In the 1960s, John Stewart Bell demonstrated that the predictions of quantum mechanics are incompatible with the principle of locality, that is, the fact that an object can be influenced directly only by its immediate surroundings and not by distant events. In particular, when remote observers perform measurements on a pair of entangled quantum particles, such as photons, the results of these measurements are highly correlated. In fact, these correlations are so strong that they cannot be explained by any physical theory respecting the principle of locality. Hence quantum mechanics is a nonlocal theory, and the fact that Nature is nonlocal has been confirmed in numerous experiments.

In a paper published in Nature Communications, Dr Brunner and Professor Linden showed that the two above subjects are in fact deeply connected with the same concepts appearing in both fields. For instance, the physical notion of locality appears naturally in games where players adopt a classical strategy. In fact the principle of locality sets a fundamental limit to the performance achievable by classical players (that is, bound by the rules of classical physics).

Next, by bringing quantum mechanics into the game, the researchers showed that players who can use quantum resources, such as entangled quantum particles, can outperform classical players. That is, quantum players achieve better performance than any classical player ever could.

Dr Brunner said: "Such an advantage could, for instance, be useful in auctions which are well described by the type of games that we considered. Therefore, our work not only opens a bridge between two remote scientific communities, but also opens novel possible applications for quantum technologies."

Air Pollution Responsible for More Than 2 Million Deaths Worldwide Each Year, Experts Estimate

More than two million deaths occur worldwide each year as a direct result of human-caused outdoor air pollution, a new study has found.

In addition, while it has been suggested that a changing climate can exacerbate the effects of air pollution and increase death rates, the study shows that this has a minimal effect and only accounts for a small proportion of current deaths related to air pollution.

The study, which has been published today, 12 July, in IOP Publishing's journal Environmental Research Letters, estimates that around 470,000 people die each year because of human-caused increases in ozone.

It also estimates that around 2.1 million deaths are caused each year by human-caused increases in fine particulate matter (PM_2.5) ? tiny particles suspended in the air that can penetrate deep into the lungs, causing cancer and other respiratory disease.

Co-author of the study, Jason West, from the University of North Carolina, said: "Our estimates make outdoor air pollution among the most important environmental risk factors for health. Many of these deaths are estimated to occur in East Asia and South Asia, where population is high and air pollution is severe."

According to the study, the number of these deaths that can be attributed to changes in the climate since the industrial era is, however, relatively small. It estimates that a changing climate results in 1500 deaths due to ozone and 2200 deaths related to PM_2.5 each year.

Climate change affects air quality in many ways, possibly leading to local increases or decreases in air pollution. For instance, temperature and humidity can change the reaction rates which determine the formation or lifetime of a pollutant, and rainfall can determine the time that pollutants can accumulate.

Higher temperatures can also increase the emissions of organic compounds from trees, which can then react in the atmosphere to form ozone and particulate matter.

"Very few studies have attempted to estimate the effects of past climate change on air quality and health. We found that the effects of past climate change are likely to be a very small component of the overall effect of air pollution," continued West.

In their study, the researchers used an ensemble of climate models to simulate the concentrations of ozone and PM_2.5 in the years 2000 and 1850. A total of 14 models simulated levels of ozone and six models simulated levels of PM_2.5.

Previous epidemiological studies were then used to assess how the specific concentrations of air pollution from the climate models related to current global mortality rates.

The researchers' results were comparable to previous studies that have analysed air pollution and mortality; however, there was some variation depending on which climate model was used.

"We have also found that there is significant uncertainty based on the spread among different atmospheric models. This would caution against using a single model in the future, as some studies have done," continued West.

NASA's OPALS to Beam Data From Space Via Laser

PASADENA, Calif. -- NASA will use the International Space Station to test a new communications technology that could dramatically improve spacecraft communications, enhance commercial missions and strengthen transmission of scientific data.

The Optical Payload for Lasercomm Science (OPALS), an optical technology demonstration experiment, could improve NASA's data rates for communications with future spacecraft by a factor of 10 to 100. OPALS has arrived at NASA's Kennedy Space Center in Florida from the agency's Jet Propulsion Laboratory in Pasadena, Calif. It is scheduled to launch to the space station later this year aboard a SpaceX Dragon commercial resupply capsule on the company's Falcon 9 rocket.

"OPALS represents a tangible stepping stone for laser communications, and the International Space Station is a great platform for an experiment like this," said Michael Kokorowski, OPALS project manager at JPL. "Future operational laser communication systems will have the ability to transmit more data from spacecraft down to the ground than they currently do, mitigating a significant bottleneck for scientific investigations and commercial ventures."

OPALS will be mounted on the outside of the International Space Station and communicate with a ground station in Wrightwood, Calif., a mountain town near Los Angeles.

"It's like aiming a laser pointer continuously for two minutes at a dot the diameter of a human hair from 30 feet away while you're walking," explained OPALS systems engineer Bogdan Oaida of JPL.

The OPALS instrument was built at JPL and is slated to fly on the Dragon capsule in late 2013. The mission is expected to run 90 days after installation on the station.

The OPALS Project Office is based at JPL, a division of the California Institute of Technology in Pasadena. 

Geothermal Power Facility Induces Earthquakes, Study Finds

An analysis of earthquakes in the area around the Salton Sea Geothermal Field in southern California has found a strong correlation between seismic activity and operations for production of geothermal power, which involve pumping water into and out of an underground reservoir.

"We show that the earthquake rate in the Salton Sea tracks a combination of the volume of fluid removed from the ground for power generation and the volume of wastewater injected," said Emily Brodsky, a geophysicist at the University of California, Santa Cruz, and lead author of the study, published online in Science on July 11.

"The findings show that we might be able to predict the earthquakes generated by human activities. To do this, we need to take a large view of the system and consider both the water coming in and out of the ground," said Brodsky, a professor of Earth and planetary sciences at UCSC.

Brodsky and coauthor Lia Lajoie, who worked on the project as a UCSC graduate student, studied earthquake records for the region from 1981 through 2012. They compared earthquake activity with production data for the geothermal power plant, including records of fluid injection and extraction. The power plant is a "flash-steam facility" which pulls hot water out of the ground, flashes it to steam to run turbines, and recaptures as much water as possible for injection back into the ground. Due to evaporative losses, less water is pumped back in than is pulled out, so the net effect is fluid extraction.

During the period of relatively low-level geothermal operations before 1986, the rate of earthquakes in the region was also low. Seismicity increased as the operations expanded. After 2001, both geothermal operations and seismicity climbed steadily.

The researchers tracked the variation in net extraction over time and compared it to seismic activity. The relationship is complicated because earthquakes are naturally clustered due to local aftershocks, and it can be difficult to separate secondary triggering (aftershocks) from the direct influence of human activities. The researchers developed a statistical method to separate out the aftershocks, allowing them to measure the "background rate" of primary earthquakes over time.

"We found a good correlation between seismicity and net extraction," Brodsky said. "The correlation was even better when we used a combination of all the information we had on fluid injection and net extraction. The seismicity is clearly tracking the changes in fluid volume in the ground."

The vast majority of the induced earthquakes are small, and the same is true of earthquakes in general. The key question is what is the biggest earthquake that could occur in the area, Brodsky said. The largest earthquake in the region of the Salton Sea Geothermal Field during the 30-year study period was a magnitude 5.1 earthquake.

The nearby San Andreas fault, however, is capable of unleashing extremely destructive earthquakes of at least magnitude 8, Brodsky said. The location of the geothermal field at the southern end of the San Andreas fault is cause for concern due to the possibility of inducing a damaging earthquake.

"It's hard to draw a direct line from the geothermal field to effects on the San Andreas fault, but it seems plausible that they could interact," Brodsky said.

At its southern end, the San Andreas fault runs into the Salton Sea, and it's not clear what faults there might be beneath the water. A seismically active region known as the Brawley Seismic Zone extends from the southern end of the San Andreas fault to the northern end of the Imperial fault. The Salton Sea Geothermal Field, located on the southeastern edge of the Salton Sea, is one of four operating geothermal fields in the area.

Researchers Regenerate Retina in Mice Using Neuronal Reprogramming

Researchers from the Centre for Genomic Regulation (CRG) in Barcelona have managed to regenerate the retina in mice using neuronal reprogramming. There are currently several lines of research that explore the possibility of tissue regeneration through cell reprogramming. One of the mechanisms being studied is reprogramming through cell fusion.

The researcher Pia Cosma and her team have used the cell fusion mechanism to reprogram the neurons in the retina. This mechanism consists of introducing bone marrow stem cells into the damaged retina. The new undifferentiated cells fuse with the retinal neurons and these acquire the ability to regenerate the tissue.

"For the first time we have managed to regenerate the retina and reprogram its neurons through in vivo cell fusion. We have identified a signalling pathway that, once activated, allows the neurons to be reprogrammed through their fusion with bone marrow cells," explains Pia Cosma, head of the Reprogramming and Regeneration group at the Centre for Genomic Regulation and ICREA research professor. "This discovery is important not only because of the possible medical applications for retinal regeneration but also for the possible regeneration of other nervous tissues," says Daniela Sanges, first author of the work and postdoctoral researcher in Pia Cosma's laboratory.

The study, published by the journal Cell Reports, demonstrates that the regeneration of nervous tissue by means of cell fusion is possible in mammals and describes this new technique as a potential mechanism for the regeneration of more complex nervous tissue.

This research is in the very early stages but already there are laboratories interested in being able to continue the work and take it to a more applied level.

Bioenergy With Carbon Capture: Scientists Set out Path for Global Warming Reversal

 Bioenergy with carbon capture and storage (BECCS) can reverse the global warming trend and push temperatures back below the global target of 2°C above pre-industrial levels, even if current policies fail and we initially overshoot this target.

This is according to a new study, published today, 11 July, in IOP Publishing's journal Environmental Research Letters, which shows that ambitious temperature targets can be exceeded then reclaimed by implementing BECCS around mid-century.

The researchers, from Chalmers University of Technology in Sweden, show that if BECCS is implemented on a large-scale along with other renewable energy sources, temperature increases can be as low as 1.5°C by 2150.

Co-author of the study, Professor Christian Azar, said: "What we demonstrate in our paper is that even if we fail to keep temperature increases below 2°C, then we can reverse the warming trend and push temperatures back below the 2°C target by 2150.

"To do so requires both large-scale use of BECCS and reducing other emissions to near-zero levels using other renewables -- mainly solar energy -- or nuclear power."

BECCS is a greenhouse gas mitigation technology based on bioenergy that produces fuel for power plants or transportation while simultaneously removing carbon dioxide from the atmosphere. Trees and crops give off carbon dioxide when they are burnt as fuel, but also act as a carbon sink as they grow beforehand, absorbing carbon dioxide from the atmosphere. These two processes cancel each other out, resulting in net zero emissions of carbon dioxide.

When combined with carbon capture and storage -- techniques that aim to pull carbon dioxide out of the flue gases from power plants and redirect it into geological storage locations -- the overall carbon dioxide emissions are negative. If applied on a global scale, this could help to reverse global warming.

In their study, the researchers developed an integrated global energy system and climate model that enabled them to assess the most cost-effective way forward for a given energy demand scenario and temperature target.

They find that stringent temperature targets can be met at significantly lower costs if BECCS is implemented 30 to 50 years from now, although this may cause a temporary overshoot of the 2°C target.

"The most policy relevant implication of our study is that even if current political gridlock causes global warming in excess of 2°C, we can reverse the temperature trend and reach targets later. This means that 2°C targets or even more ambitious targets can remain on the table in international climate negotiations," Azar continues.

However, the authors caution against interpreting their study as an argument for delaying emission reductions in the near-term.

Azar says: "BECCS can only reverse global warming if we have net negative emissions from the entire global energy system. This means that all other CO2 emissions need to be reduced to nearly zero.

"Also, temperatures can only be reduced by about 0.6°C per century, which is too slow to act as an 'emergency brake' if climate damages turn out to be too high. The more we reduce emissions now, the more ambitious targets we can achieve in the long term -- even with BECCS."

Caribbean's Native Predators Unable to Stop Aggressive Lionfish Population Growth

"Ocean predator" conjures up images of sharks and barracudas, but the voracious red lionfish is out-eating them all in the Caribbean -- and Mother Nature appears unable to control its impact on local reef fish. That leaves human intervention as the most promising solution to the problem of this highly invasive species, said researchers at the University of North Carolina at Chapel Hill.

"Lionfish are here to stay, and it appears that the only way to control them is by fishing them," said John Bruno, professor of biology in UNC's College of Arts and Sciences and lead investigator of the study. The research has important implications not just for Caribbean reefs, but for the North Carolina coast, where growing numbers of lionfish now threaten local fish populations.

Lionfish, native to the Indo-Pacific region, have long been popular aquarium occupants, with their striking stripes and soft, waving fins. They also have venomous spines, making them unpleasant fare for predators, including humans -- though once the spines are carefully removed, lionfish are generally considered safe to eat, Bruno said.

They have become big marine news as the latest invasive species to threaten existing wildlife populations. Bruno likened their extraordinary success to that of ball pythons, now eating their way through Florida Everglades fauna, with few predators other than alligators and humans.

"When I began diving 10 years ago, lionfish were a rare and mysterious species seen deep within coral crevices in the Pacific Ocean," said Serena Hackerott, lead author and master's student in marine sciences, also in UNC's College of Arts and Sciences. "They can now been seen across the Caribbean, hovering above the reefs throughout the day and gathering in groups of up to ten or more on a single coral head."

The international research team looked at whether native reef predators such as sharks and groupers could help control the population growth of red lionfish in the Caribbean, either by eating them or out-competing them for prey. They also wanted to evaluate scientifically whether, as some speculate, that overfishing of reef predators had allowed the lionfish population to grow unchecked.

The team surveyed 71 reefs, in three different regions of the Caribbean, over three years. Their results indicate there is no relationship between the density of lionfish and that of native predators, suggesting that, "interactions with native predators do not influence" the number of lionfish in those areas, the study said.

The researchers did find that lionfish populations were lower in protected reefs, attributing that to targeted removal by reef managers, rather than consumption by large fishes in the protected areas. Hackerott noted that during 2013 reef surveys, there appeared to be fewer lionfish on popular dive sites in Belize, where divers and reef managers remove lionfish daily.

The researchers support restoration of large-reef predators as a way to achieve better balance and biodiversity, but they are not optimistic that this would affect the burgeoning lionfish population.

"Active and direct management, perhaps in the form of sustained culling, appears to be essential to curbing local lionfish abundance and efforts to promote such activities should be encouraged," the study concluded.

The Sounds of Science: Melting of Iceberg Creates Surprising Ocean Din

here is growing concern about how much noise humans generate in marine environments through shipping, oil exploration and other developments, but a new study has found that naturally occurring phenomena could potentially affect some ocean dwellers.

Nowhere is this concern greater than in the polar regions, where the effects of global warming often first manifest themselves. The breakup of ice sheets and the calving and grounding of icebergs can create enormous sound energy, scientists say. Now a new study has found that the mere drifting of an iceberg from near Antarctica to warmer ocean waters produces startling levels of noise.

Results of the study are being published this month in Oceanography.

A team led by Oregon State University researchers used an array of hydrophones to track the sound produced by an iceberg through its life cycle, from its origin in the Weddell Sea to its eventual demise in the open ocean. The goal of the project was to measure baseline levels of this kind of naturally occurring sound in the ocean, so it can be compared to anthropogenic noises.

"During one hour-long period, we documented that the sound energy released by the iceberg disintegrating was equivalent to the sound that would be created by a few hundred supertankers over the same period," said Robert Dziak, a marine geologist at OSU's Hatfield Marine Science Center in Newport, Ore., and lead author on the study.

"This wasn't from the iceberg scraping the bottom," he added. "It was from its rapid disintegration as the berg melted and broke apart. We call the sounds 'icequakes' because the process and ensuing sounds are much like those produced by earthquakes."

Dziak is a scientist with the Cooperative Institute for Marine Resources Studies (CIMRS), a collaborative program between Oregon State University and NOAA based at OSU's Hatfield center. He also is on the faculty of OSU's College of Earth, Ocean, and Atmospheric Sciences.

When scientists first followed the iceberg, it encountered a 124-meter deep shoal, causing it to rotate and grind across the seafloor. It then began generating semi-continuous harmonic tremors for the next six days. The iceberg then entered Bransfield Strait and became fixed over a 265-meter deep shoal, where it began to pinwheel. The harmonic tremors became shorter and less pronounced.

It wasn't until the iceberg broke loose and drifted into the warmer waters of the Scotia Sea that the real action began. Photos from the International Space Station showed visible melt ponds on the iceberg's surface, indicating it had was in a period of rapid disintegration. Within two months, the iceberg had broken apart and scientists were no longer able to track it via satellite.

But the scientists' hydrophone array recorded the acoustic signature of the breakup -- short duration, broadband signals that were distinctly different from the harmonic tremors, and much louder.

"You wouldn't think that a drifting iceberg would create such a large amount of sound energy without colliding into something or scraping the seafloor," noted Dziak, who has monitored ocean sounds using hydrophones for nearly two decades. "But think of what happens why you pour a warm drink into a glass filled with ice. The ice shatters and the cracking sounds can be really dramatic. Now extrapolate that to a giant iceberg and you can begin to understand the magnitude of the sound energy."

"In fact, the sounds produced by ice breakup near Antarctica are often clearly recorded on hydrophones that we have near the equator," Dziak added.

Scientists are just starting to study the impact of anthropogenic and naturally occurring sounds on marine life and are unsure about the possible impacts. Most at-risk are those animals that use sound to facilitate their life-sustaining activities, such as feeding, breeding and navigation.

"The breakup of ice and the melting of icebergs are natural events, so obviously animals have adapted to this noise over time," Dziak said. "If the atmosphere continues to warm and the breakup of ice is magnified, this might increase the noise budget in the polar areas.

"We don't know what impact this may have," Dziak added, "but we are trying to establish what natural sound levels are in various parts of the world's oceans to better understand the amount of anthropogenic noise that is being generated."

The research is supported primarily by the NOAA Ocean Exploration and Research Program, the Department of Energy, and the Korea Polar Research Institute.

Asian Origins of Native American Dogs Confirmed

 Once thought to have been extinct, native American dogs are on the contrary thriving, according to a recent study that links these breeds to ancient Asia.

The arrival of Europeans in the Americas has generally been assumed to have led to the extinction of indigenous dog breeds; but a comprehensive genetic study has found that the original population of native American dogs has been almost completely preserved, says Peter Savolainen, a researcher in evolutionary genetics at KTH Royal Institute of Technology in Stockholm.

In fact, American dog breeds trace their ancestry to ancient Asia, Savolainen says. These native breeds have 30 percent or less modern replacement by European dogs, he says.

"Our results confirm that American dogs are a remaining part of the indigenous American culture, which underscores the importance of preserving these populations," he says.

Savolainen's research group, in cooperation with colleagues in Portugal, compared mitochondrial DNA from Asian and European dogs, ancient American archaeological samples, and American dog breeds, including Chihuahuas, Peruvian hairless dogs and Arctic sled dogs.

They traced the American dogs' ancestry back to East Asian and Siberian dogs, and also found direct relations between ancient American dogs and modern breeds.

"It was especially exciting to find that the Mexican breed, Chihuahua, shared a DNA type uniquely with Mexican pre-Columbian samples," he says. "This gives conclusive evidence for the Mexican ancestry of the Chihuahua."

The team also analysed stray dogs, confirming them generally to be runaway European dogs; but in Mexico and Bolivia they identified populations with high proportions of indigenous ancestry.

Savolainen says that the data also suggests that the Carolina Dog, a stray dog population in the U.S., may have an indigenous American origin.

Savolainen works at the Science for Life Laboratory (SciLifeLab www.scilifelab.se), a collaboration involving KTH Royal Institute of Technology, Stockholm University, the Karolinska Institutet and Uppsala University.

Mammals Can 'Choose' Sex of Offspring, Study Finds

A new study led by a researcher at the Stanford University School of Medicine shows that mammalian species can "choose" the sex of their offspring in order to beat the odds and produce extra grandchildren.

In analyzing 90 years of breeding records from the San Diego Zoo, the researchers were able to prove for the first time what has been a fundamental theory of evolutionary biology: that mammals rely on some unknown physiologic mechanism to manipulate the sex ratios of their offspring as part of a highly adaptive evolutionary strategy.

"This is one of the holy grails of modern evolutionary biology -- finding the data which definitively show that when females choose the sex of their offspring, they are doing so strategically to produce more grandchildren," said Joseph Garner, PhD, associate professor of comparative medicine and senior author of the study, published July 10 in PLOS ONE. The results applied across 198 different species.

The scientists assembled three-generation pedigrees of more than 2,300 animals and found that grandmothers and grandfathers were able to strategically choose to give birth to sons, if those sons would be high-quality and in turn reward them with more grandchildren. The process is believed to be largely controlled by the females, Garner said.

"You can think of this as being girl power at work in the animal kingdom," he said. "We like to think of reproduction as being all about the males competing for females, with females dutifully picking the winner. But in reality females have much more invested than males, and they are making highly strategic decisions about their reproduction based on the environment, their condition and the quality of their mate. Amazingly, the female is somehow picking the sperm that will produce the sex that will serve her interests the most: The sperm are really just pawns in a game that plays out over generations."

The study builds on a classic theory first proposed in a 1973 paper by scientists Robert Trivers and Dan Willard, founders of the field of evolutionary sociobiology. They challenged the conventional wisdom that sex determination in mammals is random, with parents investing equally in their offspring to generate a 50-50 sex ratio in the population. Instead, they hypothesized that mammals are selfish creatures, manipulating the sex of their offspring in order to maximize their own reproductive success. Thus, parents in good condition, based on health, size, dominance or other traits, would invest more in producing sons, whose inherited strength and bulk could help them better compete in the mating market and give them greater opportunities to produce more offspring. Conversely, mothers in poor condition would likely play it safe, producing more daughters, whose productivity is physiologically limited. Other hypotheses make similar predictions -- that females who choose mates with particularly "good genes" (e.g. for attractiveness) should produce so called "sexy sons" as a result, Garner said.

The hypothesis was reinforced in 1984 in a seminal Nature paper by T.H. Clutton-Brock at the University of Cambridge, who found that among wild red deer, dominant mothers produced significantly more sons than deer who held a subordinate position within the herd.

"This paper was a huge leap forward, providing the first suggestion that the idea might work in mammals," Garner said. "But because it relied on data from only two generations, it couldn't show whether females that produced more sons also gained more grandchildren from those sons." In fact, this key prediction of the hypothesis has remained untested, because complete three-generation pedigrees are so hard to obtain in the wild, Garner said.

Yet Garner and his colleagues were able to advance the research by reconstructing three-generation pedigrees of multiple species. They turned to the San Diego Zoo, enlisting the help of animal-care supervisor Greg Vicino in combing through decades of records on more than 38,000 animals from 678 species. The project was labor-intensive, requiring years of work to reconstruct the pedigrees and breeding histories of the animals, Garner said.

The researchers ended up with a pool of 1,627 granddams (female grandparents) and 703 grandsires (male grandparents) for whom they had a complete record of three generations. Major mammal groups were represented, including primates; carnivores, such as lions, bears and wolves; cloven-hoofed animals, such as cows, buffalo and deer; and odd-toed grazing animals, such as horses and rhinos.

They found that when females produced mostly sons, those sons had 2.7 times more children per capita than those whose mothers bore equal numbers of male and female offspring.

"The question is, within each species, among females who had more sons, did those sons do better in terms of producing more grandchildren per capita? And the answer is yes," Garner said. "Females are choosing and being very Machiavellian about it. They're doing it for their own benefit."

The same was true of grandsires, with the researchers showing that when grandfathers produced mostly sons, those sons on average had 2.4 times more children per capita. "A grandfather producing more male offspring also has more success. But that could be entirely determined by the female," as she may be deciding the sex ratio to produce based on the quality of the male, Garner said.

He compared the mating gambit to a kind of gambling game. "I'm gambling on how many grandchildren I'm going to produce. If I'm producing nothing but daughters, I'm making a safe bet -- I'm going to make the average."

Sons, on the other hand, are a "high-risk, high-reward bet." If an animal produces a fertile, high-quality son, in effect it has hit the jackpot in terms of reproductive potential.

"Think about lions," Garner said. "Most male lions don't reproduce. There may be 10 or 15 females but only one male that fathers everybody. The same is true with baboons. There is one alpha male. If you are the parent of that harem-holding male, then you have hit the genetic jackpot because he might produce tens or hundreds of offspring. If you have a bachelor male, who never produces offspring, he produces zero. So males are a high-risk, high-payoff bet. Who would take the bet unless they knew they could rig it?"

But how, in fact, do parents manipulate the sex of their offspring? Garner said the mechanism isn't really known, though one theory holds that females can control the "male" and "female" sperm, which have different shapes, as they move through the mucous in the reproductive tract, selectively slowing down or speeding up the sperm they want to select.

There are some notable examples of sex-ratio manipulation in the insect world; for instance, yellow dung flies, who engage in an elaborate mating game, collect sperm from different mates and then selectively choose the "best" sperm for the environmental conditions (dung) of each clutch of eggs laid, he said.

Garner said there may be some parallels among humans, with some studies suggesting that they may be able to adjust their sex-ratios in response to social cues. For instance, in polygamous societies, the top-ranking wife is much more likely to have a son than the lower-ranking wife (the son holds the economic power in the family). And a study of 400 U.S. billionaires, published in 2013, found that they were more likely to have sons than daughters -- presumably, the scientists hypothesized, because sons tend to retain the family's wealth.

Garner's personal favorite is a study published in 1988. It found that mothers with an inherited speech disorder had three times as many sons as daughters, in theory because a son with a speech impediment would have an easier time finding a mate than a speech-impaired daughter, whose success is more dependent on speech and social skills, Garner said.

Garner said their study emphasizes the huge research potential of zoo data. "The temptation might be to assume that data from captive animals in the zoo has inherent problems," he said. For instance, zoo animals are subject to managed breeding, with less opportunity to select mates. Moreover, females in the wild rely on environmental cues to tell them to produce sons or daughters, but these cues may be misleading among animals in captivity, he said.

"You would think that all of these conditions would hide the result, so the fact that females can still manipulate their sex ratio to produce an advantage despite the zoo environment makes the data even more convincing," Garner said. In fact, the study raises a concern that captive populations may be under threat, as the disproportionate success of certain individuals means that genetic variability is lost from the population faster than expected, the researchers note. Lack of genetic diversity can promote inbreeding-related health problems and a population's overall vulnerability to diseases and parasites.

A better understanding of sex-ratio manipulation in captive animals could help lead to interventions that would help preserve the species, they conclude.

Collette Thogerson, PhD, of the U.S. Fish & Wildlife Service, was the first author of the study.

One More Homo Species? 3D-Comparative Analysis Confirms Status of Homo Floresiensis as Fossil Human Species

Ever since the discovery of the remains in 2003, scientists have been debating whether Homo floresiensis represents a distinct Homo species, possibly originating from a dwarfed islandHomo erectus population, or a pathological modern human. The small size of its brain has been argued to result from a number of diseases, most importantly from the condition known as microcephaly.

Based on the analysis of 3-D landmark data from skull surfaces, scientists from Stony Brook University New York, the Senckenberg Center for Human Evolution and Palaeoenvironment, Eberhard-Karls Universität Tübingen, and the University of Minnesota provide compelling support for the hypothesis that Homo floresiensis was a distinct Homo species.

The study, titled "Homo floresiensiscontextualized: a geometric morphometric comparative analysis of fossil and pathological human samples," is published in the July 10 edition of PLOS ONE.

The ancestry of the Homo floresiensis remains is much disputed. The critical questions are: Did it represent an extinct hominin species? Could it be a Homo erectus population, whose small stature was caused by island dwarfism?

Or, did the LB1 skull belong to a modern human with a disorder that resulted in an abnormally small brain and skull? Proposed possible explanations include microcephaly, Laron Syndrome or endemic hypothyroidism ("cretinism").

The scientists applied the powerful methods of 3-D geometric morphometrics to compare the shape of the LB1 cranium (the skull minus the lower jaw) to many fossil humans, as well as a large sample of modern human crania suffering from microcephaly and other pathological conditions. Geometric morphometrics methods use 3D coordinates of cranial surface anatomical landmarks, computer imaging, and statistics to achieve a detailed analysis of shape.

This was the most comprehensive study to date to simultaneously evaluate the two competing hypotheses about the status of Homo floresiensis.

The study found that the LB1 cranium shows greater affinities to the fossil human sample than it does to pathological modern humans. Although some superficial similarities were found between fossil, LB1, and pathological modern human crania, additional features linked LB1exclusively with fossil Homo. The team could therefore refute the hypothesis of pathology.

"Our findings provide the most comprehensive evidence to date linking the Homo floresiensis skull with extinct fossil human species rather than with pathological modern humans. Our study therefore refutes the hypothesis that this specimen represents a modern human with a pathological condition, such as microcephaly," stated the scientists.

Hubble Finds a True Blue Planet: Giant Jupiter-Sized Planet Located 63 Light-Years Away

Astronomers using NASA's Hubble Space Telescope have deduced the actual visible-light color of a planet orbiting another star 63 light-years away.

If seen directly it would look like a "deep blue dot," reminiscent of Earth's color as seen from space. But that's where all comparison ends. The planet's daytime atmosphere is nearly 2,000 degrees Fahrenheit, and it possibly rains glass -- sideways -- in howling 4,500-mile-per-hour winds.

The cobalt blue color doesn't come from the reflection of a tropical ocean, but rather from a hazy blow-torched atmosphere and perhaps from high clouds laced with silicate particles. The condensation temperature of silicates could form very small drops of glass that would scatter blue light more than red light.

The turbulent alien world, cataloged HD 189733b, is one of the nearest exoplanets to Earth that can be seen crossing the face of its star. It has been intensively studied by Hubble and other observatories, and its atmosphere is dramatically changeable and exotic.

The observations yield new insights into the chemical composition and cloud structure of a bizarre "hot Jupiter" class planet, which orbits precariously close to its parent star.

Clouds often play key roles in planetary atmospheres, and detecting the presence and importance of clouds in hot Jupiters is crucial, say researchers. "We obviously don't know much on the physics and climatology of silicate clouds, so we are exploring a new domain of atmospheric physics," said team member Frederic Pont of the University of Exeter, South West England, the United Kingdom.

The team used Hubble's Space Telescope Imaging Spectrograph to measure changes in the color of light from the planet before, during, and after the passage of the planet behind the parent star. This technique is possible because the planet's orbit is tilted edge-on as viewed from Earth; therefore, it routinely passes in front of and then behind the star.

Hubble measured a small drop in light -- about one part in 10,000 -- when the planet went behind the star, and a slight change in the color of the light, too. "We saw the light becoming less bright in the blue, but not in the green or the red. This means that the object that disappeared is blue because light was missing in the blue, but not in the red when it was hidden," said Pont.

The team's study will be published online July 11 and will appear in the August 1 issue of the Astrophysical Journal Letters.

Earlier observations have reported evidence for the scattering of blue light on the planet. But this most recent Hubble observation gives confirming evidence, said the researchers.

The planet HD 189733b was discovered in 2005. At a distance of only 2.9 million miles from its parent star, the planet is so close that it is gravitationally "tidally locked" so that one side always faces the star and the other side is always dark.

In 2007 NASA's Spitzer Space Telescope measured the infrared light, or heat, from the planet. This observation produced one of the first-ever temperature maps of an exoplanet. The map shows that the dayside and night-side temperatures differ by about 500 degrees Fahrenheit. This temperature difference should cause fierce winds to roar from the daytime to nighttime side. The complementary visible-light Hubble observations reduce contamination from the planet's own hot glow, and focus on atmospheric composition.

Pont cautions that it's difficult to know exactly what causes the color of a planet's atmosphere, even for solar system planets. For example, Jupiter is reddish due to unknown color-carrying molecules. Venus does not reflect ultraviolet (UV) light due to an unknown UV absorber in the atmosphere.

Earth looks blue from space because the oceans absorb red and green wavelengths more strongly than blue light. In addition, the oceans reflect Earth's blue sky where the shorter blue wavelengths of sunlight are selectively scattered by atmospheric oxygen and nitrogen molecules in a process called Rayleigh scattering.

Solar Tsunami Used to Measure Sun's Magnetic Field

A solar tsunami observed by NASA's Solar Dynamics Observatory (SDO) and the Japanese Hinode spacecraft has been used to provide the first accurate estimates of the Sun's magnetic field.

Solar tsunamis are produced by enormous explosions in the Sun's atmosphere called coronal mass ejections (CMEs). As the CME travels out into space, the tsunami travels across the Sun at speeds of up to 1000 kilometres per second.

Similar to tsunamis on Earth, the shape of solar tsunamis is changed by the environment through which they move. Just as sound travels faster in water than in air, solar tsunamis have a higher speed in regions of stronger magnetic field. This unique feature allowed the team, led by researchers from UCL's Mullard Space Science Laboratory, to measure the Sun's magnetic field. The results are outlined in a paper soon to be published in the journalSolar Physics.

Dr David Long, UCL Mullard Space Science Laboratory, and lead author of the research, said: "We've demonstrated that the Sun's atmosphere has a magnetic field about ten times weaker than a normal fridge magnet."

Using data obtained using the Extreme ultraviolet Imaging Spectrometer (EIS), a UK-led instrument on the Japanese Hinode spacecraft, the team measured the density of the solar atmosphere through which the tsunami was travelling.

The combination of imaging and spectral observations provides a rare opportunity to examine the magnetic field which permeates the Sun's atmosphere.

Dr Long noted: "These are rare observations of a spectacular event that reveal some really interesting details about our nearest star."

Visible as loops and other structures in the Sun's atmosphere, the Sun's magnetic field is difficult to measure directly and usually has to be estimated using intensive computer simulations. The Hinode spacecraft has three highly sensitive telescopes, which use visible, X-ray and ultraviolet light to examine both slow and rapid changes in the magnetic field.

The instruments on Hinode act like a microscope to track how the magnetic field around sunspots is generated, shapes itself, and then fades away. These results show just how sensitive these instruments can be, measuring magnetic fields that were previously thought too weak to detect.

The explosions that produce solar tsunamis can send CMEs hurtling towards the Earth. Although protected by its own magnetic field, the Earth is vulnerable to these solar storms as they can adversely affect satellites and technological infrastructure.

Dr Long said: "As our dependency on technology increases, understanding how these eruptions occur and travel will greatly assist in protecting against solar activity."

Dinosaurs, diets and ecological niches: Study shows recipe for success

Dr. Jordan Mallon, a post-doctoral fellow at the museum, tackled the question by measuring and analyzing characteristics of nearly 100 dinosaur skulls recovered from the Dinosaur Park Formation in Alberta, Canada. The specimens now reside in major fossil collections across the world, including that of the Canadian Museum of Nature. The work was undertaken as part of his doctoral thesis at the University of Calgary under the supervision of Dr. Jason Anderson.

Mallon's results, published in the July 10, 2013 issue of the open-access journal PLOS ONE, indicate that these megaherbivores (all weighing greater than 1,000 kg) had differing skull characteristics that would have allowed them to specialize in eating different types of vegetation. The results support a concept known as niche partitioning, which dates to the 19th-century studies of Charles Darwin and came into its own in the 1950s with the development of the science of ecology.

The Dinosaur Park Formation is between 76.5 and 75 million years old and is known for its rich concentration of dinosaur remains. The rock unit has yielded nearly 20 species of megaherbivores from the Late Cretaceous period. Of these, six species would have coexisted at any one time, including two types of ankylosaurs (tank-like armoured dinosaurs), two types of hadrosaurs (duck-billed dinosaurs), and two types of ceratopsids (horn-faced dinosaurs).

Modern megaherbivores include elephants, giraffes, hippos and rhinos. "Today's megaherbivore communities are not nearly as diverse as those from the Late Cretaceous of Alberta, and most other fossil communities also pale by comparison. So the question is: how does an environment support so many of these large herbivores at once?" asks Mallon.

Dr. Jordan Mallon, in the fossil collections of the Canadian Museum of Nature, crouches by three of the skulls he examined for his study on niche partitioning in megaherbivores. From front to back: Lambeosaurus clavinitelis (a hadrosaur), Chasmosaurus belli, and Styracosaurus albertensis, both ceratopsids (horn-faced dinosaurs). Photo: Dan Smythe, Canadian Museum of Nature. Credit: Dan Smythe, Canadian Museum of Nature

Mallon tested two competing hypotheses. The first is that availability of food was not a limiting factor in species survival. Plants may have been either super-abundant, so the megaherbivores did not have to compete for food, or the dinosaurs' metabolisms were relatively low, so the environment could support more species relative to a fauna comprised entirely of high-metabolic animals

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The second hypothesis is that the available food resources were limiting and that niche partitioning came into play; in other words, there weren't that many plants to go around so that the species had to share available food sources by specializing on different types of vegetation.

"If niche partitioning was in effect, then you would expect to see various dietary adaptations among the coexisting dinosaur species," explains Mallon. "So you would look for differences in the shapes of the skull, in the teeth, and in the beaks that might reflect adaptations for feeding on diverse plants or plant parts." These differences, for example, would reflect whether a dinosaur was adapted to feeding on soft or hard plant tissues.

Until Mallon's study, neither of these hypotheses had been rigorously tested with such a large sample size. For each of the nearly 100 dinosaur skulls he studied, Mallon measured 12 characteristics that are known to relate to diet in modern animals. These include depth of the jaw, angle of the beak, size of muscle insertions, and length of the tooth row. "We can apply those same functional and mechanical principles to dinosaurs to see what they might tell us about niche partitioning."

Not unexpectedly, differences were found between the three major groups (ankylosaurs, hadrosaurs and ceratopsids). But more striking were the subtle yet significant differences within each of the three groups that were probably related to feeding. "We found those differences that were previously suspected but never demonstrated," explains Mallon.

As an example, the palaeontologist suggests that ankylosaurs probably specialized on eating ferns, because they stood low to the ground, and their wide beaks would have allowed them to feed efficiently on abundant, relatively low-nutrient plants. However, within this group, the family known as nodosaurids (clubless ankylosaurs) had more efficient jaw mechanics that might have enabled them to include tougher plants in their diets. In contrast, ceratopsids had skulls that suggest they were adapted to feeding on mid-sized shrubs, while the taller hadrosaurs were less picky and would have fed on anything within reach.

Although different species came and went, the same ecological roles were filled over the 1.5 million year span of the Dinosaur Park Formation. "This tells us that niche partitioning was a viable strategy for the coexistence of these animals," adds Mallon. "The study provides further evidence to explain why dinosaurs were one of the most successful groups of animals to live on this planet."

Researchers Create Inner Ear from Stem Cells, Opening Potential for New Treatments

 Indiana University scientists have transformed mouse embryonic stem cells into key structures of the inner ear. The discovery provides new insights into the sensory organ's developmental process and sets the stage for laboratory models of disease, drug discovery and potential treatments for hearing loss and balance disorders.

A research team led by Eri Hashino, Ph.D., Ruth C. Holton Professor of Otolaryngology at Indiana University School of Medicine, reported that by using a three-dimensional cell culture method, they were able to coax stem cells to develop into inner-ear sensory epithelia -- containing hair cells, supporting cells and neurons -- that detect sound, head movements and gravity. The research was reportedly online Wednesday in the journal Nature.

Previous attempts to "grow" inner-ear hair cells in standard cell culture systems have worked poorly in part because necessary cues to develop hair bundles -- a hallmark of sensory hair cells and a structure critically important for detecting auditory or vestibular signals -- are lacking in the flat cell-culture dish. But, Dr. Hashino said, the team determined that the cells needed to be suspended as aggregates in a specialized culture medium, which provided an environment more like that found in the body during early development.

The team mimicked the early development process with a precisely timed use of several small molecules that prompted the stem cells to differentiate, from one stage to the next, into precursors of the inner ear. But the three-dimensional suspension also provided important mechanical cues, such as the tension from the pull of cells on each other, said Karl R. Koehler, B.A., the paper's first author and a graduate student in the medical neuroscience graduate program at the IU School of Medicine.

"The three-dimensional culture allows the cells to self-organize into complex tissues using mechanical cues that are found during embryonic development," Koehler said.

"We were surprised to see that once stem cells are guided to become inner-ear precursors and placed in 3-D culture, these cells behave as if they knew not only how to become different cell types in the inner ear, but also how to self-organize into a pattern remarkably similar to the native inner ear," Dr. Hashino said. "Our initial goal was to make inner-ear precursors in culture, but when we did testing we found thousands of hair cells in a culture dish."

Electrophysiology testing further proved that those hair cells generated from stem cells were functional, and were the type that sense gravity and motion. Moreover, neurons like those that normally link the inner-ear cells to the brain had also developed in the cell culture and were connected to the hair cells.

Additional research is needed to determine how inner-ear cells involved in auditory sensing might be developed, as well as how these processes can be applied to develop human inner-ear cells, the researchers said.

However, the work opens a door to better understanding of the inner-ear development process as well as creation of models for new drug development or cellular therapy to treat inner-ear disorders, they said. Additional researchers involved in the work were Andrew M. Mikosz, B.S., Andrei I. Molosh, Ph.D., and Dharmeshkumar Patel, Ph.D., of Indiana University School of Medicine.

Support for the research was provided by National Institutes of Health grants RC1DC010706, R01GM086544 and R01MH52619, a Paul and Carole Stark Neurosciences Fellowship and an Indiana Clinical and Translational Sciences Institute Predoctoral Fellowship (NIH TL1RR025759).