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DALLAS - Jan. 30, 2019 - Exercise is often cited as the best preventive medicine, but how much is too much for the hearts of middle-aged athletes?

Watch video: Running to extremes: High-endurance exercise OK for heart health

Sports cardiologist Dr. Benjamin Levine led a study, now published in JAMA Cardiology, to find the answer. Dr. Levine is a Professor of Internal Medicine and Director of the Institute for Exercise and Environmental Medicine, a collaboration between UT Southwestern Medical Center and Texas Health Presbyterian Hospital Dallas.

What is coronary calcium scanning and why is it important?

Coronary calcium scanning is an imaging test that helps physicians classify patients without cardiac symptoms as low, intermediate, or high risk for heart attack. It represents how much calcium (and thus cholesterol deposits) has accumulated in the blood vessels that supply the heart. The scan can help physicians determine the need for medication, lifestyle modification, and other risk-reducing measures. Learn more

"The question has never been whether exercise is good for you, but whether extreme exercise is bad for you. For the past decade or so, there's been increasing concern that high-volume, high-intensity exercise could injure the heart. We found that high volumes of exercise are safe, even when coronary calcium levels are high," Dr. Levine said.

High-volume, high-intensity exercise was defined in this study as at least five to six hours per week at a pace of 10 minutes per mile. The average amount of high-intensity exercise in this group was eight hours per week.

Coronary calcium is a footprint of atherosclerosis, a disease in which plaque builds up in the arteries and gives rise to heart attack and stroke. When coronary calcium is detected in the heart, the clogging process within the blood vessels has begun. The majority of high-intensity athletes had low levels of coronary calcium, though their odds of having higher levels were 11 percent greater than men who exercised less. Most importantly, the researchers found that higher calcium scores did not raise the high-intensity athletes' risk for cardiovascular or all-cause mortality.

Dr. Levine studied data from the Cooper Center Longitudinal Study. A total of 21,758 generally healthy men ages 40 to 80 and without cardiovascular disease were followed for mortality between 1998 and 2013. The athletes, a majority of them in middle age, reported their physical activity levels and underwent coronary calcium scanning. Most were predominantly runners, but some were cyclists, swimmers, or rowers. A subgroup of athletes trained in three of these sports.

Women were not included in the study as their mortality rates are lower than for men.

Despite the findings that extreme exercise does not raise heart disease risk, Dr. Levine advises against using the protective effect of exercise to excuse poor lifestyle habits. "You cannot overcome a lifetime of bad behaviors - smoking, high cholesterol, hypertension - just from doing high levels of physical activity, so don't use that as a magical cure," said Dr. Levine, who holds the Distinguished Professorship in Exercise Sciences at UT Southwestern.

He also recommends caution when starting a new training program. "If you want to train for a marathon, you have to have a long-range plan to build up slowly before you achieve those volumes and intensity of exercise."

"The known benefits of regular physical activity in the general population include decreased mortality, heart disease, diabetes, and many other medical conditions which reminds us how important it is participate in regular physical activity as recommended by the 2018 Physical Activity Guidelines," said Dr. Laura DeFina, Chief Scientific Officer of The Cooper Institute and co-author of the study. "The current study shows no increased risk of mortality in high-volume exercisers who have coronary artery calcium. Certainly, these high-volume exercisers should review their cardiovascular disease risk with their primary care doctor or cardiologists and the study results provide helpful clinical guidance."

"The most important take-home message for the exercising public is that high volumes of exercise are safe. The benefits of exercise far outweigh the minor risk of having a little more coronary calcium," Dr. Levine said.

Leukaemia promotes premature ageing in healthy bone marrow cells - according to new research from the University of East Anglia.

Findings published today in the journal Blood show that healthy bone marrow cells were prematurely aged by cancer cells around them.

It is well known that ageing promotes cancer development. But this is the first time that the reverse has been shown to be true.

Importantly, the aged bone marrow cells accelerated the growth and development of the leukaemia - creating a vicious cycle that fuels the disease.

The research was led by Dr Stuart Rushworth from UEA's Norwich Medical School, in collaboration with the Earlham Institute and the Norfolk and Norwich University Hospital (UK) and the Buck Institute for Research on Ageing in California. It was funded by the Rosetrees Trust and Norfolk's Big C Charity.

The study also identified the mechanism by which this process of premature ageing occurs in the bone marrow of leukaemia patients and highlights the potential impact this could have on future treatments.

Dr Rushworth said: "Our results provide evidence that cancer causes ageing. We have clearly shown that the cancer cell itself drives the ageing process in the neighbouring non-cancer cells.

"Our research reveals that leukaemia uses this biological phenomenon to its advantage to accelerate the disease."

NOX2, an enzyme usually involved in the body's response to infection, was shown to be present in acute myeloid leukemia (AML) cells - and this was found to be responsible for creating the ageing conditions.

The research team established that the NOX2 enzyme generates superoxide which drives the ageing process.

By inhibiting NOX2, researchers showed the reduction in aged neighbouring non-malignant cells resulted in slower cancer growth.

Dr Rushworth said: "It was not previously known that leukaemia induces ageing of the local non cancer environment. We hope that this biological function can be exploited in future, paving the way for new drugs."

NEW YORK, January 30, 2019 - The MDMX and MDM2 proteins play critical roles in keeping the tumor-suppressing protein p53 from damaging the production of healthy cells. But researchers have also found a causal connection between overexpression of MDMX and MDM2 and breast cancer. Now, in a newly published paper in the journal Breast Cancer Research, scientists at The Graduate Center of The City University of New York and Hunter College are the first to report that MDMX promotes metastasis of triple-negative breast cancer--one of the most aggressive forms of the disease, and one that is more prevalent in young women and women of color. The researchers also were able to duplicate early findings from other scientists who showed that MDM2 promotes metastasis of triple negative breast cancer.

"Triple-negative breast cancer metastasizes more often, so it's one of most deadly forms of this disease," said Graduate Center and Hunter College Professor Jill Bargonetti, whose lab conducted the research. "With this research, we now know that the MDMX protein may be one of the drivers that makes this form of cancer so aggressive, and we can potentially look at targeting this and the MDM2 protein to prevent these cancers from spreading."

Methodology

To collect response data on triple-negative breast cancer, Bargonetti's team exposed mouse-model groups to cells with knocked-down MDMX or MDM2 genes. When researchers compared these groups to a mouse-model that received triple negative breast cancer cells expressing the two genes, they found a 96 percent reduction in circulation tumor cells (CTCs) in the mouse model that received the knocked-down MDMX cells and a 78 percent reduction in CTCs in mouse model that received the knocked-down MDM2 cells.

In a secondary experiment, the researchers also looked at the relationship between MDM2 and tumor growth in estrogen receptor positive breast cancer. For this work, they compared tumor size in a mouse model exposed to cells with knocked-down MDM2 and a mouse model without the knocked-down gene. They found that tumors grew at about half the rate in the knocked-down group.

Significance

The MDMX and MDM2 genes are expressed in multiple breast cancer subtypes. Determining these genes' unique effect on tumor development and metastases in various types of cancer could help researchers identify new drug targets, novel therapies and create more precise treatment regimens. Bargonetti and her team are considering next steps for advancing their findings towards potential drug development. "These studies are very expensive, but our next goal would be to test one of the small molecules known to block MDMX to see if it can inhibit metastases," she said.

Rembrandt van Rijn's paintings are renowned for their masterful representations of light and shadow and a characteristic plasticity generated by a technique called impasto. Now, scientists have analyzed impasto layers in some of Rembrandt's paintings, and the study, which is published in the journal Angewandte Chemie, reveals that the impasto unexpectedly contains a very rare lead mineral called plumbonacrite. This finding suggests that Rembrandt used a unique paint recipe.

"Before the study, one of the only [pieces of] information about impastos was that they were achieved using lead white pigment," says Victor Gonzalez at the Delft University of Technology, the Netherlands, who is a leading author of the study, which was conducted in collaboration with the Rijksmuseum, Amsterdam, the Netherlands, the Institut de Recherche de Chimie Paris, France, as well as French and Dutch Universities. "However, the precise recipe that Rembrandt used to achieve his impastos was not known," he adds.

Lead white has been used in paintings since ancient times and, even today, its painterly properties still exceed those of its less toxic analogues. At the time Rembrandt created his artworks, lead white was produced by corrosion of metallic lead, resulting in the formation of a mixture of lead carbonates containing cerussite (lead carbonate, PbCO(3)) and hydrocerussite (Pb(3)(CO(3))(2)·(OH)(2)), which is a shiny white, mixable, and fast-drying powder.

For their analysis, the scientists sampled tiny amounts of impasto paint layers in Rembrandt's Portrait of Marten Soolmans of 1634, Susanna, 1634, and Bathseba, 1654. Using a combination of synchrotron X-ray diffraction at the European Synchrotron Radiation Facility in Grenoble, France, they identified hydrocerussite and cerussite, but surprisingly, they also found another lead mineral, plumbonacrite. "Plumbonacrite is extremely rare in historic paint layers," explained the authors. "Its more notable occurrence was linked to degradation of the red lead (minimum) pigment in a Van Gogh painting," they added.

In addition, the researchers detected plumbonacrite solely in the impasto layer, never in the layers below, and the other component of lead white, cerussite, was nearly absent. Why was the impasto chemical composition different from that of the underlayer although apparently the same pigments were used?

The scientists tried to find answers by following the chemistry of lead compounds. Plumbonacrite is only stable in alkaline (basic) environments. Under the acid production conditions of lead white, the mineral rapidly transforms into (hydro)cerussite. In contrast, a stable, highly basic lead mineral is litharge (PbO). Arguing that PbO was sometimes used as a binding additive at the time, the authors proposed that Rembrandt could have added PbO in the binder for his impasto. This would explain the composition of the white pigments. In a medium made alkaline by the litharge binder, lead carbonates would back-transform to plumbonacrite.

As a next step, the authors plan to investigate other Rembrandt paintings to check if the artist consistently used the same recipe. From the point of view of art history, it would also be important to see if other painters used the same technique.

Researchers have created a new testing ground for quantum systems in which they can literally turn certain particle interactions on and off, potentially paving the way for advances in spintronics.

Spin transport electronics have the potential to revolutionize electronic devices as we know them, especially when it comes to computing. While standard electronics use an electron's charge to encode information, spintronic devices rely on another intrinsic property of the electron: its spin.

Spintronics could be faster and more reliable than conventional electronics, as spin can be changed quickly and these devices use less power. However, the field is young and there are many questions researchers need to solve to improve their control of spin information. One of the most complex questions plaguing the field is how the signal carried by particles with spin, known as spin current, decays over time.

"The signal we need to make spintronics work, and to study these things, can decay. Just like we want good cell phone service to make a call, we want this signal to be strong," said Chuan-Hsun Li, a graduate student in electrical and computer engineering at Purdue University. "When spin current decays, we lose the signal."
In the real world, electrons don't exist independently of everything around them and behave exactly how we expect them to. They interact with other particles and among different properties within themselves. The interaction between a particle's spin (an intrinsic property) and momentum (an extrinsic property) is known as spin-orbit coupling.

According to a new paper in Nature Communications, spin-orbit coupling and interactions with other particles can dramatically enhance spin current decay in a quantum fluid called Bose-Einstein condensate (BEC).

"People want to manipulate spin formation so we can use it to encode information, and one way to do this is to use physical mechanisms like spin-orbit coupling," Li said. "However, this can lead to some drawbacks, such as the loss of spin information."

The experiment was done in the lab of Yong Chen, a professor of physics and astronomy, and electrical and computer engineering at Purdue, where his team created something like a mini particle collider for BECs. Using lasers, Rubidium-87 atoms within a vacuum chamber were trapped and cooled nearly to absolute zero. (Physics junkies may recall that laser cooling technologies won the Nobel Prize in physics in 1997. Laser trapping won the Prize in 2018.)

At this point, the atoms become a BEC: the coldest and most mysterious of the five states of matter. As atoms get colder, they start to display wave-like properties. In this quantum state, they have an identity crisis; they overlap with one another and stop behaving like individuals. Although BEC isn't technically a gas, this might be the easiest way to picture it - physicists casually refer to it as quantum fluid or quantum gas.

Inside the mini quantum fluid collider, Chen's team sent two BECs with opposite spins smashing into one another. Like two clouds of gas would, they partially penetrate each other, delivering a spin current.

"A lot of fascinating phenomena occur when you collide two condensates. Originally, they're superfluid, but when they collide, part of the friction can turn them to thermal gas," Chen said. "Because we can control every parameter, this is a really efficient system to study these kinds of collisions."

Using this system, researchers can literally turn spin-orbit coupling on and off, which allows them to isolate its effect on spin current decay. This can't be done with electrons in solid-state materials, which is part of what makes this system so powerful, Chen said.

So-called quantum gas is the cleanest system man can make. There's no disorder, which makes it possible to create a pure spin current and study its properties. Chen hopes to keep using this experimental testing ground and their bosonic spin current to further explore many fundamental questions in spin transport and quantum dynamics.

"One important challenge for spintronics and other related quantum technologies is to reduce decay so we can propagate spin information over longer distances, for longer times," he said. "With this new knowledge of the role of spin-orbit coupling, this may help people gain new insights to reduce spin decay and potentially also design better spintronic devices."

Nostalgia for events experienced by members of your own group can make you prefer domestic products over foreign ones, concludes the first systematic investigation into the effects of collective nostalgia on consumer decisions. The results could help countries bolster domestic industries without resorting to hard interventions, such as tariffs or international trade re-negotiations.

Personal nostalgia, a longing for one's personal past, has long been used by companies to sell products. Less is known, however, about how collective nostalgia influences consumer choices. Collective nostalgia is the sentimental longing for a group with which a person identifies. For example, when thinking about themselves as being American, many Americans will bring to mind iconic past events, such as the first moon landing, the Olympic Games in Los Angeles, or the election of the first black U.S. president. Collective nostalgia is a group-level emotion that heightens social connectedness and strengthens collective self-esteem.

Marika Dimitriadou, a lecturer in marketing at the Athens Metropolitan College, Boris Maciejovsky, an associate professor of management at the University of California, Riverside, and Tim Wildschut and Constantine Sedikides, professors of social and personality psychology at the University of Southampton, thought that collective nostalgia would increase consumer preference for domestically manufactured products.

In a series of experiments conducted in Greece, the researchers assigned volunteers to one of three groups. The first group was given a short writing assignment intended to evoke nostalgia for events that they shared with fellow Greeks. Another group was presented with scenarios and experiences that would have been common during childhood for their generation and intended to spark collective nostalgia. The third group was a control, assigned a task that was not expected to evoke any particular sort of nostalgia.

All participants were then asked to state a preference for particular Greek or foreign pop songs or TV shows. Volunteers in the groups that experienced collective nostalgia preferred Greek pop songs or TV shows across all the experiments. Whenever they thought fondly about times they had shared with their fellow Greeks the volunteers preferred domestic products. Participants in the control group preferred foreign songs and shows.

The magnitude of collective nostalgia's effect on domestic preference was large and consistent. The researchers believe that collective nostalgia boosted participants' feeling that their national ingroup is a worthwhile entity, or collective self-esteem, which subsequently elevated domestic country preference.

The findings suggest that organizations and marketers could harness collective nostalgia to reach consumers and influence their decisions.

Collective nostalgia could be evoked in large and abstract groups, even when the members of these groups have never met. Organizations and marketers can use iconic events in a group's shared history to evoke collective nostalgia in broad swathes of their target audience and, by so doing, shape their product preferences.

"We think that collective nostalgia can be leveraged in domains that are extensions of the self, such as clothes, cars, or experiences, getting people to choose domestic over foreign products," said Maciejovsky. "This could be more effective than hard interventions, like tariffs or trade re-negotiations."

NEW YORK -- In a scientific first, Columbia neuroengineers have created a system that translates thought into intelligible, recognizable speech. By monitoring someone's brain activity, the technology can reconstruct the words a person hears with unprecedented clarity. This breakthrough, which harnesses the power of speech synthesizers and artificial intelligence, could lead to new ways for computers to communicate directly with the brain. It also lays the groundwork for helping people who cannot speak, such as those living with as amyotrophic lateral sclerosis (ALS) or recovering from stroke, regain their ability to communicate with the outside world.

These findings were published today in Scientific Reports.

"Our voices help connect us to our friends, family and the world around us, which is why losing the power of one's voice due to injury or disease is so devastating," said Nima Mesgarani, PhD, the paper's senior author and a principal investigator at Columbia University's Mortimer B. Zuckerman Mind Brain Behavior Institute. "With today's study, we have a potential way to restore that power. We've shown that, with the right technology, these people's thoughts could be decoded and understood by any listener."

Decades of research has shown that when people speak -- or even imagine speaking -- telltale patterns of activity appear in their brain. Distinct (but recognizable) pattern of signals also emerge when we listen to someone speak, or imagine listening. Experts, trying to record and decode these patterns, see a future in which thoughts need not remain hidden inside the brain -- but instead could be translated into verbal speech at will.

But accomplishing this feat has proven challenging. Early efforts to decode brain signals by Dr. Mesgarani and others focused on simple computer models that analyzed spectrograms, which are visual representations of sound frequencies.

But because this approach has failed to produce anything resembling intelligible speech, Dr. Mesgarani's team turned instead to a vocoder, a computer algorithm that can synthesize speech after being trained on recordings of people talking.

"This is the same technology used by Amazon Echo and Apple Siri to give verbal responses to our questions," said Dr. Mesgarani, who is also an associate professor of electrical engineering at Columbia's Fu Foundation School of Engineering and Applied Science.

To teach the vocoder to interpret to brain activity, Dr. Mesgarani teamed up with Ashesh Dinesh Mehta, MD, PhD, a neurosurgeon at Northwell Health Physician Partners Neuroscience Institute and co-author of today's paper. Dr. Mehta treats epilepsy patients, some of whom must undergo regular surgeries.

"Working with Dr. Mehta, we asked epilepsy patients already undergoing brain surgery to listen to sentences spoken by different people, while we measured patterns of brain activity," said Dr. Mesgarani. "These neural patterns trained the vocoder."

Next, the researchers asked those same patients to listen to speakers reciting digits between 0 to 9, while recording brain signals that could then be run through the vocoder. The sound produced by the vocoder in response to those signals was analyzed and cleaned up by neural networks, a type of artificial intelligence that mimics the structure of neurons in the biological brain.

The end result was a robotic-sounding voice reciting a sequence of numbers. To test the accuracy of the recording, Dr. Mesgarani and his team tasked individuals to listen to the recording and report what they heard.

"We found that people could understand and repeat the sounds about 75% of the time, which is well above and beyond any previous attempts," said Dr. Mesgarani. The improvement in intelligibility was especially evident when comparing the new recordings to the earlier, spectrogram-based attempts. "The sensitive vocoder and powerful neural networks represented the sounds the patients had originally listened to with surprising accuracy."

Dr. Mesgarani and his team plan to test more complicated words and sentences next, and they want to run the same tests on brain signals emitted when a person speaks or imagines speaking. Ultimately, they hope their system could be part of an implant, similar to those worn by some epilepsy patients, that translates the wearer's thoughts directly into words.

"In this scenario, if the wearer thinks 'I need a glass of water,' our system could take the brain signals generated by that thought, and turn them into synthesized, verbal speech," said Dr. Mesgarani. "This would be a game changer. It would give anyone who has lost their ability to speak, whether through injury or disease, the renewed chance to connect to the world around them."

HOUSTON -- (Jan. 29, 2019) -- In his free time last summer, Rice University geoscientist Ming Tang made a habit of comparing the niobium content in various rocks in a global minerals database. What he found was worth skipping a few nights out with friends.

In a paper published this month by Nature Communications, Tang, Rice petrologist Cin-Ty Lee and colleagues offered an answer to one of Earth science's fundamental questions: Where do continents form?

"If our conclusions are correct, every piece of land that we are now sitting on got its start someplace like the Andes or Tibet, with very mountainous surfaces," said Tang, lead author of the study and a postdoctoral research associate in Rice's Department of Earth, Environmental and Planetary Sciences (EEPS). "Today, most places are flat because that is the stable stage of the continental crust. But what we found was that when the crust formed, it had to start out with mountain-building processes."

The connection between niobium, one of Earth's rarest elements, and continent formation is a story that plays out over billions of years at scales as small as molecules and as large as mountain ranges. The leading players are niobium and tantalum, rare metals so alike that geologists often think of them as twins.

"They have very similar chemical properties and behave almost identically in most geological processes," Tang said. "If you measure tantalum and niobium, you find that their ratio is nearly constant in Earth's mantle. That means that when you find more niobium in a rock, you will find more tantalum, and when you find less niobium, you will find less tantalum."

The mantle is Earth's thickest layer, spanning about 1,800 miles between the planet's core and its thin outer crust. Earth scientists believe that little, if anything, moves between the mantle and core, but the mantle and everything above it -- seafloor, oceans, continents and atmosphere -- are connected, and many of the atoms on Earth's surface today, including the atoms in humans and other living things, have cycled through the mantle one or more times in Earth's 4.6 billion years.

The rocks in continents are an exception. Geologists have found some that are up to 4 billion years old, which means they were formed near the surface and stayed on the surface, without being recycled into the mantle. That's due in part to the nature of continental crust, which is far less dense than the basaltic rocks beneath Earth's oceans. Lee, professor and EEPS department chair, said it's no coincidence that Earth is the only rocky planet known to have both continents and life.

"Every day we live on continents, and we take most of our resources from continents," Lee said. "We have oxygen in the air to breath and just the right temperature to support complex life. These things are so common that we take them for granted, but Earth didn't start off with these conditions. They developed later in Earth's history. And the emergence of continents is one of the things that shaped our planet and made it more livable."

Scientists still lack details about how continents got their start and how they grew to cover 30 percent of Earth's surface, but one big clue relates to niobium and tantalum, the geochemical twins.

"On average, the rocks in continental crust have about 20 percent less niobium than they should compared to the rock we see everywhere else," Tang said. "We believe this missing niobium is tied to the mystery of continents. By solving or finding the missing the niobium, we can get important information about how continents form."

Geologists have known about the imbalance for decades. And it certainly suggests that the geochemical processes that produce continental crust also remove niobium. But where was the missing niobium?

That nagging question prompted Tang to spend his free time perusing records in the Max Planck Institute's GEOROC database, a comprehensive global collection of published analyses of volcanic rocks.

Based on those searches and months of follow-up tests, Tang, Lee and colleagues offer the first physical evidence that "arclogites" (pronounced ARC-loh-jyts) are responsible for the missing niobium. Arclogites are cumulates, the leftover dross that accumulates near the base of continental arcs. On rare occasions, chunks of these cumulates erupt onto the surface from volcanos.

The Rice group first sent arclogite samples that Lee had collected in Arizona to their collaborator, Kang Chen, a research fellow based at the China University of Geosciences in Wuhan. Chen spent a month getting precise readings of the relative amounts of niobium and tantalum in the samples. The rocks were created when the High Sierras were an active continental arc, like the Andes today.

Chen's tests confirmed high niobium-tantalum ratios, but to better understand the mechanism by which this signature was developed, Tang and Lee used high precision laser ablation and "inductively coupled plasma mass spectrometry" in Lee's laboratory at Rice to reveal the mineral rutile was responsible.

"Rutile is the mineral that hosts the niobium," he said. "It's a naturally occurring form of titanium oxide, and it is what actually 'sees' the difference between niobium and tantalum and captures one more than the other."

But that happens only under specific conditions. For example, Tang said that at temperatures above 1,000 degrees Celsius, rutile traps normal ratios of tantalum and niobium. It only begins to prefer niobium when temperatures drop below 1,000 degrees Celsius. Tang said the only known place with that set of conditions is deep beneath continental arcs, like the Andes today or the High Sierras about 80 million years ago.

"The reason you need high pressure is that titanium oxide is relatively rare," he said. "You need very high pressure to force it to crystalize and fall out of the magma."

In an earlier arclogite study published in Science Advances last May, Tang and Lee discovered a subtle chemical signature that can explain why continental crust is iron-depleted. Lee said that finding and the discovery about rutile and niobium illustrate the central importance of continental arcs in Earth history.

"Continental arcs are like a magic system that links everything together, from climate and oxygen concentrations in the atmosphere to ore deposits," Lee said. "They're a sink for carbon dioxide after they die. They can drive greenhouse or icehouse, and they are the building blocks of continents."

A team of mathematicians has determined the ideal wing shape for fast flapping flight--a discovery that offers promise for better methods for harvesting energy from water as well as for enhancing air speed.

The work, which appears in the journal Proceedings of the Royal Society A, relies on a technique that mimics evolutionary biology to ascertain which structure yields the best pace.

"We can simulate biological evolution in the lab by generating a population of wings of different shapes, have them compete to achieve some desired objective, in this case, speed, and then have the best wings 'breed' to make related shapes that do even better," says Leif Ristroph, an assistant professor at New York University's Courant Institute of Mathematical Sciences and the paper's senior author.

In making these determinations, the researchers conducted a series of experiments in NYU's Applied Math Lab. Here, they created 3D-printed wings that are flapped mechanically and raced against one another, with the winners "breeding" via an evolutionary or genetic algorithm to create ever faster flyers.

A video of the experimental process and conclusions may be viewed here: https://www.youtube.com/watch?v=ZCbZZ8OpP-g (Caption: Experiments revealing ideal airfoil shapes for flapping flight, with the flows generated at the front part of the wing [red] and the rear [green] visualized using fluorescent dyes. The best wing shapes are found to make strong vortices at the trailing edge that were not interfered with by the vortices generated at the leading edge. Credit: NYU's Applied Math Lab).

In order to mimic this breeding process, the researchers began the experiment with 10 different wing shapes whose propulsion speeds were measured. The algorithm then selected pairs of the fastest wings ("parents") and combined their attributes to create even-faster "daughters" that were then 3D-printed and tested. They repeated this process to create 15 generations of wings, with each generation yielding offspring faster than the previous one.

"This 'survival of the fastest' process automatically discovers a quickest teardrop-shaped wing that most effectively manipulates the flows to generate thrust," explains Ristroph. "Further, because we explored a large variety of shapes in our study, we were also able to identify exactly what aspects of the shape were most responsible for the strong performance of the fastest wings."

Their results showed that the fastest wing shape has a razor-thin trailing edge, which helps to generate strong vortices or swirling flows during flapping. The wing leaves a trail of these eddies as it pushes off the fluid to propel forward.

"We view the work as a case study and proof-of-concept for a much broader class of complex engineering problems, especially those that involve objects in flows, such as streamlining the shape to minimize drag on a structure," observes Ristroph. "We think this could be used, for example, to optimize the shape of a structure for harvesting the energy in water waves."

The exceptional climate-altering capabilities of cattle are mainly due to methane, which they blast into the atmosphere during their daily digestive routine. Cattle urine is a lesser-known climate offender. It produces nitrous oxide (N2O), which has warming power far greater than that of carbon dioxide (CO2), the main driver of global warming. A study conducted by the International Center for Tropical Agriculture (CIAT) and partners shows that these N2O emissions can be significantly curbed by healthy cattle pastures.

For the study, researchers collected urine from cattle at research sites in five countries across Latin America and the Caribbean. They spilled these 500 mL samples on paired cattle fields classified as degraded or healthy, which was determined by vegetation coverage. In six of the seven test sites, degraded pastures emitted significantly more N2O - sometimes up to three times as much. The results were published January 29 in Scientific Reports, an open-access journal by the publishers of Nature.

"Degraded pastures are bad in so many ways," said Ngonidzashe Chirinda, a CIAT researcher and the study's lead author. "This study adds to the case for land restoration. Degraded pastures not only affect food security and the livelihood of farmers today, but affects the livelihood of future farmers because they emit more gases that cause global warming."

The results add urgency to global land restoration agreements, including Initiative 20x20, which aims to bring into restoration 20 million hectares of land into restoration in Latin America by 2020 as a first major step toward even more ambitious restoration targets.

Estimates vary, but Chirinda calculates, conservatively, that there are 150 million hectares of degraded lands in Latin America. Brazil alone is home to some 80 million hectares of degraded pastureland.

Degraded livestock land is generally characterized by overgrazing, soil compaction, loss of organic material and low levels of nutrients and soil carbon. Large-scale land restoration with improved forage grasses, rotational grazing and the addition of shrubs and trees (silvopastoral farming) could significantly mitigate the negative climate effects wrought by degradation. In addition to reducing N2O emissions, restored landscapes generally contain more carbon, have healthier soils and more robust and productive livestock.

"This study highlights the importance of avoiding land degradation in the first place," said Todd Rosenstock, a co-author based at World Agroforestry (ICRAF). "Maintaining healthy pastures appears to reinforce goals of both the United Nations' Framework Convention on Climate Change and the UN Convention to Combat Desertification simultaneously."

The curious results from the single test site that did not align with the study results - in Taluma, Colombia - may be attributed to a number of factors that merit further research. N2O emissions there were by far the lowest at any test site and were the same on both degraded and healthy pastures. The cattle urine used in the experiment had the lowest nitrogen content compared to the other research sites, which likely contributed to the results. The forage grass used there, Brachiaria humidicola, also has an especially high nitrification inhibition capacity, meaning that it prevents nitrogen from becoming N2O.

Power of data from far-flung places

The study is a victory for well-designed, modest-budget science. The project began with a weeklong training session at CIAT headquarters in Cali, Colombia, where a team of Ph.D. students from the additional participating countries - Argentina, Brazil, Nicaragua and Trinidad and Tobago - helped design the research plan and standardized the study's methodology.

The students returned to their home countries and carried out the experiment to coincide with their area's rainy seasons, to assure similar climate conditions across study sites. (The exception was Taluma, which was sampled during a period characterized by low rainfall, which is also another possible reason why the N2O emissions were lower there).

"The power is in the number of data points from all the different countries," said Chirinda.

Better cattle greenhouse gas estimates

Researchers said the study is a useful step toward creating a more detailed picture of the scope of greenhouse gas emissions from cattle farming in LAC.

"Since work on emissions from livestock in the region is not common, this study generates at least one piece of information that is missing from theoretical greenhouse gas estimates in the LAC region," said Miguel Andrés Arango, a co-author and scientist at Colombia's AGROSAVIA, the nation's largest agriculture research organization.

"Being able to estimate the real impact of cattle production will allow us to propose potential practices for reducing emissions," said Arango. "It is high time we know the emission factors for our agricultural systems."

Binge and heavy drinking may trigger a long-lasting genetic change, resulting in an even greater craving for alcohol, according to a Rutgers-led study in the journal Alcoholism: Clinical & Experimental Research.

"We found that people who drink heavily may be changing their DNA in a way that makes them crave alcohol even more," said Distinguished Professor Dipak K. Sarkar, senior author of the study and director of the Endocrine Program in the Department of Animal Sciences at Rutgers University-New Brunswick. "This may help explain why alcoholism is such a powerful addiction, and may one day contribute to new ways to treat alcoholism or help prevent at-risk people from becoming addicted."

In 2016, more than 3 million people died from the harmful use of alcohol, according a World Health Organization report. That is 5 percent of all global deaths. More than three-quarters of alcohol-caused deaths were among men. The harmful use of alcohol also caused 5.1 percent of the worldwide toll of disease and injuries.

Scientists at Rutgers and Yale University School of Medicine focused on two genes implicated in the control of drinking behavior: PER2, which influences the body's biological clock, and POMC, which regulates our stress-response system.

By comparing groups of moderate, binge and heavy drinkers, the researchers found that the two genes had changed in the binge and heavy drinkers through an alcohol-influenced gene modification process called methylation. The binge and heavy drinkers also showed reductions in gene expression, or the rate at which these genes create proteins. These changes increased with greater alcohol intake.

Additionally, in an experiment, the drinkers viewed stress-related, neutral or alcohol-related images. They also were shown containers of beer and subsequently tasted beer, and their motivation to drink was evaluated. The result: alcohol-fueled changes in the genes of binge and heavy drinkers were associated with a greater desire for alcohol.

The findings may eventually help researchers identify biomarkers - measurable indicators such as proteins or modified genes - that could predict an individual's risk for binge or heavy drinking, said Sarkar, who works in the School of Environmental and Biological Sciences.

A new study in The Condor: Ornithological Applications shows that certain endangered owls may continue to persist and even flourish after large forest fires.

Throughout western North America, longer, hotter fire seasons and dense fuels are yielding more frequent, larger, and higher-severity wildfires. Spurred by climate change, megafires in the region are often characterized by unusually large, continuous patches of high-severity fire in mature forests.

The Great Gray Owl is an endangered species in California. The Great Gray Owl population was recently estimated at fewer than 100 pairs in the state. The 2013 Rim Fire burned 104,000 acres in Yosemite National Park and Stanislaus National Forest, making it the largest recorded fire in California's Sierra Nevada region. The fire perimeter contained 23 meadows known to be occupied by Great Gray Owls during the decade prior to the fire, representing nearly a quarter of all known or suspected territories in California at the time.

Researchers analyzed 13 years of Great Gray Owl detection data (from 2004 to 2016) from 144 meadows in the central Sierra Nevada, including meadows inside and outside the Rim Fire perimeter in Yosemite National Park and on Stanislaus National Forest.

During three years of surveys after the fire, Great Gray Owls were found at 21 of 22 meadows surveyed within the fire perimeter that were occupied during the decade prior to the fire. The researchers surveyed 144 meadows in at least one year prior to the 2013 Rim fire; 54 of these were also surveyed during at least a year after the fire. Researchers found Great Gray Owls at least once at 89 meadows, with detections at 68 of 92 meadows in Yosemite National Park, and at 21 of 52 meadows outside of National Parks.

Rather than decreasing after the fire, persistence of owls at meadows actually increased on both National Park Service and other lands, while colonization rates exhibited no significant change. Great Gray Owls appear to have been largely resilient to effects of the Rim Fire during the three years after it burned.

Stable occupancy and increased site persistence after fire suggest an overall resilience to the effects of the fire during the three years after it burned. Any negative effects stemming from loss in nesting habitat appear to have been counterbalanced by other factors. Because Great Gray Owls most typically nest in the rotting remains of substantially deteriorated trees, fire could potentially enhance Great Gray Owl nesting habitat by killing large trees that become suitable nesting structures. Another positive effect of fire could be to enhance conditions for meadow-dwelling rodent populations that constitute the primary prey of Great Gray Owls.

Many researchers and land managers believe that forest thinning to reduce fire risk is critical to ensure the persistence of wildlife species associated with these forests. But this research suggests suggest forest resilience treatments are not needed to protect Great Gray Owls, and conservation efforts might be better directed to other needs of the species.

"The Rim fire looked like a worst-case scenario for California's Great Gray Owls, because it was pretty much centered on the heart of the population, and affected up to a quarter of all the territories in California," said the paper's lead researcher, Rodney B. Siegel. "Our discovery that the owls remained and in many cases even continued to nest at the burned sites after the fire is good news for Great Gray Owls. We need to keep monitoring this population to find out if the owls will continue to use these burned sites over the longer-term, as the trees that were killed by the fire deteriorate and eventually fall."

Inmates want to quit smoking but don't have access to smoking cessation programs in state prisons, increasing the risk - especially among black male inmates -- of cancer, heart disease, stroke and other smoking-related diseases, according to Rutgers researchers.

In a study published in Health Psychology Open, researchers examined smoking behaviors and characteristics of 169 black and non-black male inmates in three state correctional facilities in the Northeast to identify racial differences in their smoking behaviors and motivation to quit. Some previous studies suggest that black male smokers - in and out of prison - may be less likely to respond to treatment than other racial and ethnic groups despite their stronger desire to quit.

"Our study will help health researchers and smoking cessation treatment specialists to better understand the smoking behaviors of inmates - why they begin and continue to smoke - in order to better tailor and implement important cessation programs to assist them in quitting for life," said lead author Pamela Valera, an assistant professor at Rutgers School of Public Health.

Statistics show that black men are six times more likely to be imprisoned than non-Hispanic white men. They also face higher rates of cigarette smoking both in and out of prison and are more likely to die from smoking-related diseases.

Given the high rates of tobacco related problems in U.S. prisons and racial disparity, relapse to smoking is common among black inmates and black men returning to society. Valera said many prisons could add additional resources to help inmates quit tobacco smoke but have instead introduced smoking bans, which cannot prevent inmate from smoking or prevent them from returning to smoking after their release.

"Despite the number of different smoking cessation aids available, less than half of the people in both study groups had a medical professional in prison talk to them about quitting," said Valera. "Many of these inmates want to quit. They just lack the means and understanding on how to do so."

Valera's recommendations include:

Tobacco dependence treatments to help people quit using cigarettes and other tobacco products, including menthol cigarettes, which are popular among black smokers in and out of prison.

Prison-wide smoking cessation programs that reduce negative peer influence and help inmates who want to quit smoking live with cellmates who still smoke.

Help inmates who have quit smoking to be a positive influence on other inmates.

The smoking behavior trends found in the study include:

Smoking rates were high among both black and non-black inmates, who began or continued to smoke in prison.

Both groups want to quit smoking, although black smokers were slightly more interested.

While cigarettes were the most frequently used tobacco product, both groups use other products, including pipes, cigars and chew/snuff, although non-black smokers were slightly more likely to use them.

Menthol cigarette use was high among both groups.

Among people in both groups who had tried to quit smoking, many indicated it had been at least a year or more since they last attempted to quit, and a majority of smokers in both groups who were able to quit relapsed within less than a year.

A majority of people in both groups had not used any form of smoking cessation treatment to help them quit.

More than half of people in both groups reported that their cellmate smokes around them.

Total release foggers, commonly known as "bug bombs," are ineffective at removing cockroaches from indoor environments, according to a new study from North Carolina State University.

Bug-bomb chemicals fail to reach places where cockroaches congregate the most - on the underside of surfaces and inside cabinets, NC State researchers say. Besides leaving behind numerous cockroaches, bug bombs also leave behind nasty toxic residue in the middle of floors and countertops, areas cockroaches generally avoid but which are heavily used by humans and pets.

"There's been a general assumption that bug bombs work to eliminate cockroaches indoors, but no one had conducted a formal assessment of their efficacy and any exposure risks," said Zachary DeVries, an NC State postdoctoral researcher and the lead author of the study, published in BMC Public Health. "We've done that simultaneously in this study."

To understand more about the effectiveness of total release foggers, the researchers tested four different commercially available bug bombs with various insecticide active ingredients in five different apartment complexes with moderate to severe infestations of German cockroaches (Blattella germanica), common indoor household pests.

"All the fogger products contained pyrethroids, a class of fast-acting insecticides, and some contained piperonyl butoxide, a chemical that prevents roaches from metabolizing, or breaking down, the insecticide," said Coby Schal, Blanton J. Whitmire Distinguished Professor of Entomology at NC State and senior author of the paper.

After gauging estimates of cockroach populations in 20 homes, the researchers set off the bug bombs, following the labels' instructions - and U.S. Environmental Protection Agency guidelines on preparing the homes for fogger release - to the letter.

The researchers then monitored cockroach populations two weeks and one month after the bombs were released and found no declines from the pre-intervention estimates.

"The bug-bomb products did absolutely nothing to control cockroach populations in these homes," DeVries said.

Meanwhile, the researchers treated 10 additional homes with either a commercially available gel bait or a professional-grade gel bait. Gel baits are generally applied in small dabs via syringe, so they can be placed directly in the places where cockroaches hide. In contrast to the bug bombs, these baits were effective, after two and four weeks, in eliminating cockroach populations in the 10 homes.

To further test the effectiveness of bug bombs, the researchers placed both roaches raised in the lab and roaches captured in the homes into greased cages - making them inescapable - and set the cages on the floor and in upper cabinets of the studied homes during the deployment of the bug bombs.

"The lab roaches, which are not hardy, had high mortality, as expected," DeVries said. "The roaches captured in the homes and then brought back, however, had far lower mortality rates than you would expect from direct exposure to bug bombs, confirming the ineffectiveness of these products when used for German cockroach control."

The researchers also examined whether bug bombs increased insecticide exposure risks in the homes. Prior to doing that, however, they swabbed floors and kitchen surfaces and found insecticide residue already present.

"Baseline levels of insecticides in these homes makes sense, because residents with moderate to severe cockroach infestations are likely to use insecticides to attempt to eliminate roaches," DeVries said. "However, what was most disconcerting was that these swabs were collected from the middle of floors and kitchen surfaces, locations where roaches don't generally congregate."

Four to six hours after the bug bombs were deployed, the researchers again swabbed floors, kitchen surfaces, walls and cabinets and found average insecticide residues increased 600 times baseline levels on all horizontal surfaces.

One month later, those surfaces were swabbed again; 34 percent still had higher insecticide residue levels than the baseline.

"Bug bombs are not killing cockroaches; they're putting pesticides in places where the cockroaches aren't; they're not putting pesticides in places where cockroaches are and they're increasing pesticide levels in the home," DeVries said. "In a cost-benefit analysis, you're getting all costs and no benefits."

"This is of particular concern in low-income communities, where bug bombs are frequently used because professional pest control may be too expensive," Schal added.

BUFFALO, N.Y. -- Surgery to remove the thymus gland in patients with myasthenia gravis (MG), a rare autoimmune disease affecting neuromuscular function, provides significant clinical benefits for as long as five years after the procedure, according to a paper published on Jan. 25 in The Lancet Neurology.

The study followed 68 patients for up to five years after undergoing thymectomy, the surgical removal of the thymus gland. The benefits they exhibited included improved disease outcomes, less immunosuppressive medications and fewer hospitalizations to address disease exacerbations. These benefits reduce health care costs.

The paper describes the results of an extension study of a subset of MG patients who were involved in MGTX, an international trial published previously that definitively confirmed the benefit of thymectomy even in MG patients without a chest tumor.

As many as 60,000 Americans have been diagnosed with MG and its incidence is increasing, a result of improved diagnostic techniques and an aging population. Symptoms of MG may include droopy eyelids; blurred or double vision; difficulty speaking, swallowing and breathing; and muscle weakness.

Long-lasting benefit

"Our current findings reinforce the benefit of thymectomy seen in that original study, dispelling doubts about the procedure's benefits and how long those benefits last," said Gil I. Wolfe, MD, lead author of the international team that conducted the current study, Irvin and Rosemary Smith Chair of the Department of Neurology in the Jacobs School of Medicine and Biomedical Sciences at the University at Buffalo and president of UBMD Neurology. "We do hope that the new findings help reverse the apparent reluctance to do thymectomy and that the proportion of patients with MG who undergo thymectomy will increase."

Wolfe was clinical chair and lead author for the main MGTX trial, which was reported in the New England Journal of Medicine in 2016, one of the longest and largest clinical trials in the history of MG.

That trial, which followed patients for three years, was the first to definitively confirm the benefits of surgically removing the thymus early in the course of the disease. Patients who had the surgery were compared to those who hadn't in terms of disease status and how much of the corticosteroid prednisone they needed. Patients who had undergone thymectomy needed about a third-less prednisone to control their disease and also had improved disease outcomes.

The researchers conducted the current study to determine for how long after surgery that benefit could be sustained.

"In prior retrospective studies, there was skepticism that the impact of thymectomy would persist beyond three to four years," said Wolfe. "The assumption was that after that, the rates of improvement would be identical between patients who had had a thymectomy and those who had not."

The new results, based on patients' clinical status, medication requirements and adverse events, proved that assumption incorrect. The researchers found that the benefit from thymectomy continues to be seen up to five years after the procedure with improvement continuing to exceed that seen with medical therapy alone.

Patients who had the surgery and continued to take prednisone were able to take significantly lower doses of the steroid than patients who didn't have the surgery.

More patients had no functional limitations

The data were evaluated using commonly accepted outcomes for the disease, such as the Quantititave MG Score (QMG) and the proportion of patients with no functional limitations from the disease other than some muscle weakness, known as minimal manifestation status. Significantly more patients who had thymectomy were able to achieve this minimal manifestation status than those who hadn't.

"When you look at minimal manifestation rates in patients who underwent thymectomy, they are pretty much the highest reported for any population of MG patients after five to seven years of focused management," said Wolfe.

He added that another important result of the clinical benefits seen in patients undergoing thymectomy is the resulting economic benefit.

"We have evidence at both three and five years after surgery that the need for hospitalizations, such as intensive care admissions to treat MG exacerbations, is reduced by some two-thirds compared to medical therapy alone," he said.