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BIRMINGHAM, Ala. - While studying one of the smallest DNA viruses known, Sunnie Thompson, Ph.D., may have found a new way to help prevent kidney damage following organ transplant.

The University of Alabama at Birmingham researcher studies BK polyomavirus, a major source of kidney damage and rejection in transplant recipients. Nearly all humans silently harbor polyomaviruses in their bodies; but when transplant recipients receive drugs to suppress their immune system to prevent graft rejection, the virus can reactivate, resulting in damage to the kidney.

No FDA-approved therapy exists to combat BK polyomavirus. Thompson, an associate professor in the UAB Department of Microbiology, says that, if their findings can be verified in human patients, they may have discovered a new way to reduce BK polyomavirus levels in transplant patients without reducing the immunosuppressing drugs that are needed to prevent transplant rejection.

Thompson's findings came through basic research on the virus, now published as a featured article in the Journal of Virology.

With only seven genes, the polyomavirus must commandeer the host cell's DNA replication machinery in order to produce new viruses. To do this, the virus forces host cells to start replicating to subvert the cell's proteins into making copies of the virus. Viral replication activates a response to DNA damage; but it was unclear why this was important for viral replication, so Thompson's laboratory set out to understand how activation of the DNA damage response helped the virus.

The DNA damage response involves two major proteins called ATM and ATR that are recruited to sites of DNA damage. Activation of this response leads to DNA repair, arrest of cell replication while the DNA is being repaired, or cell death if the DNA damage is too severe. Thompson and her colleagues inhibited ATM or ATR in infected cells, which revealed that the virus activated the DNA damage response in order to arrest the cell cycle. This kept the cell's proteins available to continue to replicate the virus.

When ATR was inhibited in cells infected with BK polyomavirus, infected cells began to divide while they were still making DNA. This led to severe DNA damage and decreased viral production.

The role for ATM was different. ATM was needed for the virus to start host DNA replication. ATM also prevented the cell from entering mitosis, though only after DNA replication was completed, resulting in reduced viral production, but with no DNA damage.

Importantly, these inhibitors did not alter the cell cycle or increase DNA damage in uninfected cells. Only BK polyomavirus-infected cells treated with these inhibitors had increased cell division, which reduced viral titers. Since these inhibitors are already in clinical trials as cancer drugs, this may provide an opportunity to use them to reduce BK polyomavirus levels in kidney transplant patients with active BK polyomavirus infections. The current standard of care is to reduce the drugs that suppress the immune system, which increases the chances of transplant rejection.

For all the evidence that the benefits of reducing greenhouse gases outweigh the costs of regulation, disturbingly few domestic climate change policies have been enacted around the world so far.

So say UC Santa Barbara professor and economist Kyle Meng, and co-author Ashwin Rode, a former UCSB Ph.D. student now at the University of Chicago, in a paper published in the journal Nature Climate Change.

"There is a striking disconnect between what is needed to avoid dangerous climate change and what has actually been done to date," said Meng, a professor in the Bren School of Environmental Science & Management and in the Department of Economics. One common explanation for that disconnect, he added, is that jurisdictions are reluctant to adopt climate policy when they can simply benefit from the reductions implemented by other jurisdictions.

However, say Meng and Rode, the political process that leads to climate change regulation can be a barrier to its own legislation.

"There is an increasing concern that this lack of climate action may be due to political influences," said Meng, who is also a director at the Bren-based Environmental Market Solutions Lab (emLab). Lobbying between special interest groups and the legislators they target can decrease the chances of putting such policies into effect.

To illustrate this, the researchers examined the role of political lobbying in the private sector around the 2009-2010 Waxman-Markey (WM) Bill. Also known as the American Clean Energy and Security Act, the energy bill was the most prominent -- and promising -- U.S. climate bill to date. And its failure nearly a decade ago continues to shape climate policies today, including the current uncertainty surrounding future global climate negotiations.

"Basically, without a binding U.S. climate policy, there is very little pressure for countries around the world to step up and adopt their own serious climate mitigation plans," Meng explained.

At the time the bill was proposed, according to the researchers, lobbying around WM was called "the sum of all lobbies." In total, companies spent more than $700 million lobbying the bill; about 14% of that was spent between 2009 and 2010. Taking into account data from comprehensive U.S. lobbying records and combining them with an empirical method for forecasting the policy's effect on the value of publicly listed firms, the researchers were able to estimate how the stock values of these firms would change had WM been implemented.

Their approach also allowed them to determine which firms were expected to gain or lose value from the policy. Knowing who the winners and losers were would allow the researchers to determine if they were differentially effective in influencing the policy's chances. According to Meng and Rode's statistical analyses, lobbying by firms expecting losses was more effective than lobbying by firms expecting gains.

All told, the total lobbying by these companies reduced the bill's chances by 13 percentage points, from 55% to 42%, representing $60 billion (2018 dollars) in expected climate damages due to the lowered chance of enacting U.S. climate policy.

This is the first study to quantify the effects of lobbying in altering the likelihood of enacting climate policy. Generally, lack of data has made it difficult to examine who is spending how much to influence the process, and what data there is often does not reveal who would win or lose, or by how much.

"Our findings also provide a glimmer of hope by paving a path toward more politically robust climate policies," Meng said. The authors show that the very political forces that lowered WM's chances could have been leveraged to instead reduce political opposition. For instance, WM was a cap-and-trade bill that issued a "capped" number of emission permits which regulated companies could trade in order to comply with the policy. Some of these permits are typically allocated freely to regulated companies. If such free permits are better targeted towards oppositional firms, they may in turn reduce political opposition against the policy.

"Subtle design changes to market-based climate policies can alleviate political opposition and increase chances of adoption," Meng said.

Scientists of Far Eastern Branch of the Russian Academy of Sciences (FEB RAS), Far Eastern Federal University (FEFU) and National Taiwan University comprehended state of the art scientific knowledge about plants stress response activated by unfavorable environmental factors. Researchers proposed ways to improve crop plants stress resistance by developing one's heritable stress response memory which will allow preserving the stability of the yield obtained worldwide. A related review published in Trends in Plant Science.

International biotechnology teams have long been taking actions to boost plants resistance to major stressors provoking crop loss like heat, cold, lack of/ excess of light, drought/excess of moisture, as well as various combinations of these factors. However, current methods are developed with no full consideration of the stress response mechanisms based on different variants of intercellular communication in plant organisms.

Biotechnologists from FEFU, FEB RAS, and the National Taiwan University have scrutinized how the main mechanisms through which plant cells learn about the stressful situation and react to it -- abscisic acid (ABA) signal subsystems and heat shock proteins -- interact with each other. Scientists have pointed out that SWI/SNF proteins play an important role in the interaction between these subsystems., These proteins are responsible for remodeling of chromatin, i.e. the basis of chromosomes -- the ones where the vast majority of inherited information is concentrated, and which are intended for its storage, realization, and transfer. Ultimately, SWI/SNF proteins may be involved in the formation of a plants stress memory. They were proposed for bioengineering treatment aimed to increase the stress resistance of plants.

'SWI/SNF is a remodeling protein complex containing in all organisms whose cells have nuclei. This group of proteins is responsible for the way DNA is repackaged without changing its molecular structure. In plants, the complex is responsible for growth, development, reaction to stress and -- along with ABA and heat shock proteins signal subsystems that it binds -- for the stress memory formation. We studied scientific works related. Based on them, we proposed several ways to adjust the SWI/SNF chromatin-remodeling proteins, as well as the associated components of the signaling subsystems, with the goal to develop a memory about stress experienced by the plants of initial and subsequent generations. Thus, we are talking about the concept of plants "bioengineering memory", which will increase plant resistance to stress' Said Viktor Bulgakov, Doctor of Biological Sciences, Corresponding Member of the Russian Academy of Sciences, FEFU Professor, who devised the concept of the article published.

The scientist went on that the mechanism of plants memory about stress experienced and the transfer of the 'memories' from the first to the next generations is still a little-studied area, but research in this field is attracting great attention.

In the article, scientists warn of temperance, which is necessary in bioengineering manipulations with the stress tolerance of plants. All methods should be as close as possible to the natural adaptation of plants to stress.

'For this, biotechnologists can use the most advanced genomic editing technologies. For example, the CRISPR-Cas9 method allows one to 'tweak' the function of the plant gene with no introducing alien information into the plant's DNA. This means that in Russia it will be possible to completely abandon GMOs in the sense it understood traditionally. Actually, this is the purpose of our work carried out under the grant. In the USA, products created via CRISPR-Cas9 technology are recognized as indistinguishable from natural selection products' Victor Bulgakov noted.

Scientists also urge to take into account the phenomenon of plants 'memory' when planning all subsequent experiments to improve plants stress resistance.

The hypothesis that traits acquired in one generation can be passed through to the next generations was first expressed by Jean-Baptiste Lamarck in the 19th century. At the beginning of the 20th century, this prompted USSR Academician Lysenko to try to grow wheat in an unsuitable climate. The consequences of the experiment were devastating. Later, the concept of heredity of acquired traits was considered with a reasonable degree of skepticism, until its popularity was revived several years ago by progress in the field of genomics and epigenetics.

It is now reliably known that the previous moderate impact may protect the plant from future stress or contribute to its acclimatization, which may persist until subsequent exposure. Thus, it is widely accepted that plants have the 'memory'-like ability.

CHAMPAIGN, Ill. -- After exposing more than 70 million grain amaranth seeds to a soil-based herbicide, researchers were not able to find a single herbicide-resistant mutant. Though preliminary, the findings suggest that the mutation rate in amaranth is very low, and that low-level herbicide application contributes little - if anything - to the onset of new mutations conferring resistance, researchers say.

The study is reported in the journal Weed Science.

Any major stress that does not kill a plant can contribute to genetic mutations in its seeds and pollen, said University of Illinois crop sciences professor Patrick Tranel, who led the new research. Even the ultraviolet light in sunlight can stress a plant and increase the likelihood of mutations in its offspring, he said. Such mutations increase genetic diversity, which can be useful to a species' survival.

"Resistance to herbicides comes from genetic variation in a population," Tranel said. "If an individual weed has the right mutation that allows it to survive a particular herbicide, that individual will survive and pass the trait to its progeny."

The relative contribution of new mutations to the problem of herbicide resistance is poorly understood, Tranel said. He and his colleagues hoped to determine the baseline mutation rate for a plant of the genus Amaranthus, a group that includes waterhemp, Palmer amaranth and other problematic agricultural weeds. They also wanted to test whether herbicide applications that failed to kill the plant increased that baseline rate.

The researchers started with a single seed of Amaranthus hypochondriacus, which is closely related to several agricultural weeds but is not known to harbor herbicide-resistance genes. Using a greenhouse to isolate their experiments from potential contamination from other Amaranthus species, the team cultivated this one plant, collected its seeds and began the long process of growing generations of related plants and harvesting the seeds.

"A good plant would produce about 100,000 seeds," Tranel said. "From this one plant, we eventually got more than 70 million seeds."

Despite the laboratory's isolation and the vigilance of the scientists, a few other Amaranthus weed seeds made their way into the experiment.

"These seeds are tiny and cling to things. You can have a seed stuck to your skin and not know it," Tranel said. "One of the students found a weed seed in his eyebrow after he left the greenhouse."

Luckily for the scientists, the seeds of the weedy Amaranthus species are black, while their test plants produced only light-colored seeds.

To screen the seeds for herbicide resistance, the researchers spread them over the surface of soil treated with a type of herbicide known as an ALS inhibitor, then waited to see whether any of the seedlings survived. Very few of the test plants overcame the herbicide treatment. Rigorous testing revealed that those rare plants that did survive were the offspring of seeds of weedy amaranth species that already carried the resistance genes.

The experiments verified that the scientists' approach worked well for screening vast numbers of seeds. It also established that the team would have to test many more than 70 million seeds to determine the baseline mutation rate in A. hypochondriacus - and to figure out if low-level herbicide treatment increases that rate, Tranel said.

Knowing this is essential to developing models that can accurately predict how plants will behave in a field, he said.

"Herbicide resistance is an evolutionary process, and evolutionary processes are mathematical," Tranel said. "If you know more precisely how plants will behave under different environmental conditions, you can develop equations that will predict how fast resistance will evolve."

If, as the study suggests, the mutation rate is much lower than expected, it doesn't mean that herbicide resistance will not occur, he said. "It may be that resistance happens a bit more slowly than previously thought," he said. "But it will still occur."

Embedded at the end of chromosomes are structures called "telomeres" that in normal cells become shorter as cells divide. As the shortening progresses it triggers cell proliferation arrest or death. Cancer cells adopt different strategies to overcome this control mechanism that keeps track of the number of times that a cell has divided. One of these strategies is the alternative lengthening of telomeres (ALT) pathway, which guarantees unlimited proliferation capability. Now, a research group led by Claus M. Azzalin at Instituto de Medicina Molecular João Lobo Antunes (iMM; Portugal: https://imm.medicina.ulisboa.pt/en/investigacao/labs/azzalin-claus-m-lab/) has discovered that a human enzyme named FANCM (Fanconi anemia, complementation group M) is absolutely required for the survival of ALT tumor cells. The results were now published in the open access journal Nature Communications*. Future strategies targeting the activity of this molecule in ALT tumor cells can constitute the basis of a novel therapeutic protocol for the treatment of these tumors.

ALT tumors are approximately 10% of the human tumors, and often develop in children (for example, juvenile osteosarcoma) and they are particularly resistant to conventional chemotherapy. "Contrary to the canonical telomere elongation mechanism that activates the enzyme telomerase, these tumor cells specifically use this alternative pathway which is insensitive to therapeutic approaches based on telomerase inhibition", explains Claus M. Azzalin, group leader at iMM.

"Previous studies have shown that a sustained physiological telomere damage must be maintained in these cells to promote telomere elongation. This scenario implies that telomeric damage levels be maintained within a specific threshold that is high enough to trigger telomere elongation, yet not too high to induce cell death", says Bruno Silva, first author of this work. Using a series of molecular biology-, cell biology- and biochemistry-based experiments, the research team found an essential role for FANCM, a component of the DNA damage repair machineries of the cell. "What we have found is that ALT cells require the activity of the FANCM in order to prevent telomere instability and consequent cell death", says Bruno Silva. "When we remove FANCM from ALT tumor cells, telomeres become heavily damaged and cells stop dividing and die very quickly. This is not observed in tumor cells that express telomerase activity or in healthy cells, meaning that is a specific feature of ATL tumor cells", explains Claus M. Azzalin.

"In our view, this is very exciting because it indicates that transiently drugging FANCM activity in ALT cells should lead to very fast cell death specifically in these cells, and sets the potential basis for an alternative therapeutic protocol for this type of tumors", adds Claus Azzalin.

A new compound developed by University of Sheffield experts has killed antibiotic resistant gram-negative bacteria, including E. coli, during tests

New treatments for gram-negative bacteria are vital as they are rapidly becoming immune to current drugs

Antimicrobial resistance is already responsible for 25,000 deaths in the EU each year

The research could pave the way for new treatment of life-threatening superbugs

A new compound which visualises and kills antibiotic resistant superbugs has been discovered by scientists at the University of Sheffield and Rutherford Appleton Laboratory (RAL).

The team, led by Professor Jim Thomas, from the University of Sheffield's Department of Chemistry, is testing new compounds developed by his PhD student Kirsty Smitten on antibiotic resistant gram-negative bacteria, including pathogenic E. coli.

Gram-negative bacteria strains can cause infections including pneumonia, urinary tract infections and bloodstream infections. They are difficult to treat as the cell wall of the bacteria prevents drugs from getting into the microbe.

Antimicrobial resistance is already responsible for 25,000 deaths in the EU each year, and unless this rapidly emerging threat is addressed, it's estimated by 2050 more than 10 million people could die every year due to antibiotic resistant infections.

Doctors have not had a new treatment for gram-negative bacteria in the last 50 years, and no potential drugs have entered clinical trials since 2010.

The new drug compound has a range of exciting opportunities. As Professor Jim Thomas explains: "As the compound is luminescent it glows when exposed to light. This means the uptake and effect on bacteria can be followed by the advanced microscope techniques available at RAL.

"This breakthrough could lead to vital new treatments to life-threatening superbugs and the growing risk posed by antimicrobial resistance."

The studies at Sheffield and RAL have shown the compound seems to have several modes of action, making it more difficult for resistance to emerge in the bacteria. The next step of the research will be to test it against other multi-resistant bacteria.

In a recent report on antimicrobial resistant pathogens, the World Health Organisation put several gram-negative bacteria at the top of its list, stating that new treatments for these bacteria were 'Priority 1 Critical' because they cause infections with high death rates, are rapidly becoming resistant to all present treatments and are often picked up in hospitals.

The research, published in the journal ACS Nano, describes the new compound which kills gram-negative E. coli, including a multidrug resistant pathogen said to be responsible for millions of antibiotic resistant infections worldwide annually.

The ROSETTA-Ice project, a three-year, multi-institutional data collection survey of Antarctic ice, has assembled an unprecedented view of the Ross Ice Shelf, its structure and how it has been changing over time. In a study published today in Nature Geoscience, the ROSETTA-Ice team members detail how they discovered an ancient geologic structure that restricts where ocean water flows. The discovery suggests that local ocean currents may play a critical role in the ice shelf's future retreat.

Ice shelves are massive expanses of floating ice that slow down the flow of Antarctic ice into the ocean. ROSETTA-Ice collected data from the massive Ross Ice Shelf, which helps slow the flow of about 20 percent of Antarctica's grounded ice into the ocean -- equivalent to 38 feet of global sea level rise. Antarctica's ice is already melting at an accelerating rate. Predicting how the ice shelf will change as the planet continues to warm requires understanding the complex ways in which the ice, ocean, atmosphere and geology interact with each other.

To gain a better understanding of these processes, the multidisciplinary ROSETTA-Ice team approached the Ross Ice Shelf much like explorers visiting a new planet for the first time. The team faced the key challenge of how to gather data from a region the size of Spain, and where ice that is frequently more than a thousand feet thick prevents more traditional ship-based surveys of the seabed. The solution was IcePod, a first-of-its kind system designed to collect high-resolution data across the polar regions. IcePod was developed at Columbia University's Lamont-Doherty Earth Observatory and mounted on a cargo plane. Its instruments measure ice shelf height, thickness and internal structure, and the magnetic and gravity signal of the underlying rock.

Each time the team flew across the ice shelf, the IcePod's magnetometer (which measures Earth's magnetic field) showed a flat and almost unchanging signal. That is, until halfway across the ice shelf, when the instrument came alive, displaying large variations, much like the heartbeat on a cardiogram. When the team mapped their results, it became clear that this "heartbeat" always appeared in the middle of the ice shelf, identifying a previously unmapped segment of the geologic boundary between East and West Antarctica.

The team then used IcePod's measurements of Earth's gravity field to model the shape of the sea floor beneath the ice shelf. "We could see that the geological boundary was making the seafloor on the East Antarctic side much deeper than the West, and that affects the way the ocean water circulates under the ice shelf," explained Kirsty Tinto, the Lamont research scientist who led all three field expeditions and is lead author of the study.

Using the new map of the seabed under the ice shelf, the team ran a model of ocean circulation and its effect on ice shelf melting. Compared with the Amundsen Sea to the east, where warm water crosses the continental shelf to cause rapid melting of the ice shelves, little warm water reaches the Ross Ice Shelf. In the Ross Sea heat from the deep ocean is removed by the cold winter atmosphere in a region of open water, called the Ross Shelf Polynya, before flowing under the ice shelf. The model showed that this cold water melts deeper portions of east Antarctic glaciers, but it is steered away from the west Antarctic side by the depth change at the ancient tectonic boundary.

In a surprise twist, however, the team found that the polynya also contributes to a region of intense summertime melting along the ice shelf's leading edge. This melting was confirmed in the radar images of the ice shelf's internal structure. "We found that the ice loss from the Ross Ice Shelf and flow of the adjoining grounded ice are sensitive to changes in processes along the ice front, such as increased summer warming if sea ice or clouds decrease," said Laurie Padman, a co-author and senior scientist at Earth and Space Research.

Overall, the results indicate that models used to predict Antarctic ice loss in future climates must consider changing local conditions near the ice front, not just the large-scale changes in the circulation of warm deep water. "We found out that it's these local processes we need to understand to make sound predictions," said Tinto.

Winters in the northern hemisphere are brutal. The harsh conditions drive some species to hibernate; bears reduce their metabolic state to conserve energy until spring. Forests also endure winter by conserving energy; they shut down photosynthesis, the process by which a green pigment called chlorophyll captures sunlight and carbon dioxide (CO2) to produce the chemical energy that fuels the plants. The total production of chemical energy resulting from photosynthesis is called Gross Primary Production (GPP). GPP in evergreen forests tells scientists how much CO2 these vast and remote systems are breathing in.

Because photosynthesis pulls CO2 out of the atmosphere, understanding forest activity is crucial for tracking global carbon levels. For decades, scientists have used satellites to monitor the changes in greenness of deciduous forests to track GPP. In the fall and winter, deciduous leaves turn brown and drop when they're dormant. In the spring and summer, the chlorophyll returns as green leaves and photosynthesis ramps up. However, evergreen trees retain their chlorophyll-filled green needles year round, preventing scientists from detecting the onset and decline of photosynthesis on a large scale.

For the first time, a new study has linked seasonal GPP cycles to a process that occurs with photosynthesis but has recently become trackable by certain satellites--solar-induced fluorescence (SIF). Photosynthesis occurs when the sun's energy excites chlorophyll into a higher energy state. When the chlorophyll returns to its normal state it emits a photon, producing light too low for the naked eye. The resulting "glow" is the SIF.

A collaborative team of researchers used a scanning spectrometer on a tower to measure fluorescent "glow" throughout the season in a Colorado evergreen forest. The team is the first to link SIF with needle physiology, canopy photosynthesis and satellite-derived fluorescence. They found that daily and seasonal SIF patterns closely matched the timing and magnitude of GPP. In the springtime, evergreens activate chlorophyll in their needles, which drives both fluorescence and photosynthesis, matching closely with SIF that satellites have recently been able to measure.

One of the ways plants protect themselves during the harsh winters is by deploying photoprotective pigments that act as "sunscreen." The study found that when plants apply this sunscreen, both photosynthesis and fluorescence decrease, enabling scientists to feel confident in the SIF signal as a proxy to monitor the breathing (CO2 uptake) of evergreen forests.

Now, scientists can use the satellite-based fluorescence measurements as an indicator of photosynthetic activity in evergreen forests at an unprecedented scale. By seeing the glow of evergreen forests from space, we can better understand how these forests are responding to climate change.

"We are trying to develop techniques to be able to 'see' photosynthesis at large scales, so we know just how much CO2 the biosphere is consuming...keeping a finger on the pulse of the biosphere," said Troy Magney, research scientist of the NASA Jet Propulsion Laboratory and the California Institute of Technology.

Magney and the team collected data from a spectrometer system mounted atop a tower between June 2017 and June 2018 in a subalpine conifer forest at Niwot Ridge, Colorado. They were able to untangle the physiological changes inside the conifer needles to better understand why we see SIF seasonal cycles. Turns out, it's all about the pigments.

"You and I can get sunburned. Too much ultraviolet radiation will damage our cells. Some people can protect themselves-- their skin produces more of the pigment melanin to adjust to high-light environments," said David Bowling, biology professor at the University of Utah and coauthor of the study. "Plants have a different, but similar process."

Without photosynthesis to utilize the sun's energy, plants need to protect themselves. The researchers found that the conifers produced high levels of pigments that are part of the xanthophyll cycle that shields its tissues from excess light. Throughout the season, the fraction of "sunscreen" changes--more in the winter, less in the summer--decreasing both fluorescence and photosynthesis.

"Ultimately, measuring the small fluorescent glow from plants will allow us to see exactly timing and magnitude of carbon uptake from the terrestrial biosphere. This will help us understand how forests are responding to climate change and suggest how they might respond to future climate change," said Magney.

Recent archaeological finds of ancient preserved apple seeds across Europe and West Asia combined with historical, paleontological, and recently published genetic data are presenting a fascinating new narrative for one of our most familiar fruits. In this study, Robert Spengler of the Max Planck Institute for the Science of Human History traces the history of the apple from its wild origins, noting that it was originally spread by ancient megafauna and later as a process of trade along the Silk Road. These processes allowed for the development of the varieties that we know today.

The apple is, arguably, the most familiar fruit in the world. It is grown in temperate environments around the globe and its history is deeply intertwined with humanity. Depictions of large red fruits in Classical art demonstrate that domesticated apples were present in southern Europe over two millennia ago, and ancient seeds from archaeological sites attest to the fact that people have been collecting wild apples across Europe and West Asia for more than ten thousand years. While it is clear that people have closely maintained wild apple populations for millennia, the process of domestication, or evolutionary change under human cultivation, in these trees is not clear.

Several recent genetic studies have demonstrated that the modern apple is a hybrid of at least four wild apple populations, and researchers have hypothesized that the Silk Road trade routes were responsible for bringing these fruits together and causing their hybridization. Archaeological remains of apples in the form of preserved seeds have been recovered from sites across Eurasia, and these discoveries support the idea that fruit and nut trees were among the commodities that moved on these early trade routes. Spengler recently summarized the archaeobotanical and historical evidence for cultivated crops on the Silk Road in a book titled Fruit from the Sands, published with the University of California Press. The apple holds a deep connection with the Silk Road - much of the genetic material for the modern apple originated at the heart of the ancient trade routes in the Tien Shan Mountains of Kazakhstan. Furthermore, the process of exchange caused the hybridization events that gave rise to the large red sweet fruits in our produce markets.

Understanding how and when apple trees evolved to produce larger fruits is an important question for researchers, because fruit trees do not appear to have followed the same path towards domestication as other, better-understood crops, such as cereals or legumes. Many different wild and anthropogenic forces apply selective pressure on the crops in our fields, it is not always easy to reconstruct what pressures caused which evolutionary changes. Therefore, looking at evolutionary processing in modern and fossil plants can help scholars interpret the process of domestication. Fleshy sweet fruits evolve to attract animals to eat then and spread their seeds; large fruits specifically evolve to attract large animals to disperse them.

Large fruits evolved to attract ancient megafauna

While most scholars studying domestication focus on the period when humans first start cultivating a plant, in this study Spengler explores the processes in the wild that set the stage for domestication. Spengler suggests that understanding the process of evolution of large fruits in the wild will help us understand the process of their domestication. "Seeing that fruits are evolutionary adaptations for seed dispersal, the key to understanding fruit evolution rests in understanding what animals were eating the fruits in the past," he explains.

Many fruiting plants in the apple family (Rosaceae) have small fruits, such as cherries, raspberries, and roses. These small fruits are easily swallowed by birds, which then disperse their seeds. However, certain trees in the family, such as apples, pears, quince, and peaches, evolved in the wild to be too large for a bird to disperse their seeds. Fossil and genetic evidence demonstrate that these large fruits evolved several million years before humans started cultivating them. So who did these large fruits evolve to attract?

The evidence suggests that large fruits are an evolutionary adaptation to attract large animals that can eat the fruits and spread the seeds. Certain large mammals, such as bears and domesticated horses, eat apples and spread the seeds today. However, prior to the end of the last Ice Age, there were many more large mammals on the European landscape, such as wild horses and large deer. Evidence suggests that seed dispersal in the large-fruiting wild relatives of the apple has been weak during the past ten thousand years, since many of these animals went extinct. The fact that wild apple populations appear to map over glacial refugial zones of the Ice Age further suggests that these plants have not been moving over long distances or colonizing new areas in the absence of their original seed-spreaders.

Trade along the Silk Road likely enabled the development of the apple we know today

Wild apple tree populations were isolated after the end of the last Ice Age, until humans started moving the fruits across Eurasia, in particular along the Silk Road. Once humans brought these tree lineages back into contact with each other again, bees and other pollinators did the rest of the work. The resulting hybrid offspring had larger fruits, a common result of hybridization. Humans noticed the larger fruiting trees and fixed this trait in place through grafting and by planting cuttings of the most favored trees. Thus, the apples we know today were primarily not developed through a long process of the selection and propagation of seeds from the most favored trees, but rather through hybridization and grafting. This process may have been relatively rapid and parts of it were likely unintentional. The fact that apple trees are hybrids and not "properly" domesticated is why we often end up with a crabapple tree when we plant an apple seed.

This study challenges the definition of "domestication"' and demonstrates that there is no one-shoe-fits-all model to explain plant evolution under human cultivation. For some plants, domestication took millennia of cultivation and human-induced selective pressure - for other plants, hybridization caused rapid morphological change. "The domestication process is not the same for all plants, and we still do not know much about the process in long-generation trees," notes Spengler. "It is important that we look past annual grasses, such as wheat and rice, when we study plant domestication. There are hundreds of other domesticated plants on the planet, many of which took different pathways toward domestication." Ultimately, the apple in your kitchen appears to owe its existence to extinct megafaunal browsers and Silk Road merchants.

Having multiple-birth babies can be a time of wonder and excitement, however, according to the first-ever international collaborative report released today, these babies and their families can face serious disadvantages compared to parents of single-birth babies.

Led by Twins Research Australia based at the University of Melbourne, the report identifies common challenges facing these families, including greater risk of pregnancy complications and premature birth, infant development delays and special needs, as well as financial, psychological and social support obstacles.

Researchers are calling for urgent action in the areas of research, education, policy and practice to ensure health services and professionals can better meet the needs of multiple-birth families.

Over the last 40 years, multiple births in Australia have almost doubled with 9056 multiple-births in 2017, compared to 4740 in 1975. This is a 91 per cent increase.

Murdoch Children's Research Institute Honorary Fellow Christie Bolch said the report showed that health knowledge, services and practices have not kept pace with this rise.

"Twins - plus triplets and above - bring many special experiences. But at every point of contact in our health system these families experience disadvantage, and this is not well recognised," Dr Bolch said.

"There is a pressing unmet need for adequately funded resources for parents of young multiples to address their unique challenges such as increased social isolation, anxiety and depression, inadequate bereavement support when one or more babies do not survive, and caring for infants with special needs."

University of Melbourne Director of Twins Research Australia John Hopper said adequate support must be provided to ensure all children receive the best start in life.

"These findings demonstrate where our knowledge is lacking - such as the challenges of staggered discharge for the families of multiple-birth babies, the long-term costs to a family when multiples are born prematurely and the factors that contribute to developmental delays," Professor Hopper said.

"We also show how to close these gaps through better research to understand the physical and mental health concerns of these families, improved education for health professionals and parents, and robust polices to address the financial disadvantage experienced."

Strategies identified in the report include extended recovery services, special care and postnatal ward policies, as well as better training about the heightened support needs of families with multiples, and structured, multiple-specific early parenting education programs.

HAMILTON, ON May 24, 2019 - McMaster researchers have developed a simple and highly novel form of computing by shining patterned bands of light and shadow through different facets of a polymer cube and reading the combined results that emerge.

The material in the cube reads and reacts intuitively to the light in much the same way a plant would turn to the sun, or a cuttlefish would change the color of its skin.

The researchers are graduate students in chemistry supervised by Kalaichelvi Saravanamuttu, an associate professor of chemistry and chemical biology whose lab focuses on ideas inspired by natural biological systems.

The researchers were able to use their new process to perform simple addition and subtraction questions.

"These are autonomous materials that respond to stimuli and do intelligent operations," says Saravanamuttu. "We're very excited to be able to do addition and subtraction this way, and we are thinking of ways to do other computational functions."

The researchers' work, published today in the journal Nature Communications, represents a completely new form of computing, one they say holds the promise of complex and useful functions yet to be imagined, possibly organized along the structures of neural networks.

The form of computing is highly localized, needs no power source and operates completely within the visible spectrum.

The technology is part of a branch of chemistry called nonlinear dynamics, and uses materials designed and manufactured to produce specific reactions to light.

A researcher shines layered stripes of light through the top and sides of a tiny, glass case holding the amber-coloured polymer, itself roughly the size of a die used in a board game. The polymer starts as a liquid and transforms to a gel in reaction to the light.

A neutral carrier beam passes through the cube from the back, toward a camera that reads the results, as refracted by the material in the cube, whose components form spontaneously into thousands of filaments that react to the patterns of light to produce a new three-dimensional pattern that expresses the outcome.

"We don't want to compete with existing computing technologies," says co-author Fariha Mahmood, a master's student in chemistry. "We're trying to build materials with more intelligent, sophisticated responses."

The mental health of children and young people with some long term physical conditions could benefit from cognitive behavioural therapy (CBT), according to a recent study from the University of Exeter Medical School. The systematic review used robust methods to bring together and make sense of the best science in this area.

Among a range of findings, the team identified some evidence of the benefits of CBT in inflammatory bowel disease, chronic pain and epilepsy. The research was funded by the National Institute for Health Research (NIHR) and supported by the NIHR Collaboration for Leadership in Applied Health Research and Care South West Peninsula (PenCLAHRC).

Long term conditions are common in children. In England, 23% of secondary school age pupils reported that they had a long-term medical illness or disability in a recent survey. Children and young people who have long term conditions are four times more likely to experience feelings of depression, anxiety and other mental health issues than those who are physically healthy.

Study author Dr Liz Shaw, said: "As well as looking at whether treatments worked for these children, we also included studies that explored the experiences of people giving and receiving the treatments. These studies highlighted the benefits of building good relationships and providing treatments in what feels like a 'safe space'."

Fiona Lockhart, Co-investigator from the Biomedical Research Centre Patient & Public Involvement Group at University College London, said: "Children and young people with long-term health conditions face enormous challenges. As well as their physical illness, many of these young people suffer from mental health problems as a consequence of their condition."

The team also found some benefit from parenting programmes to reduce behavioural problems in children with acquired brain injury and/or cerebral palsy. Further studies showed that children and young people valued treatments that considered a range of needs rather than just focussing on their mental health. The opportunity to meet and build a supportive relationship with people who are managing their long term condition was also seen to help some young people by providing them with a sense of hope for the future and learn skills to manage their physical and mental health.

Study author Dr Michael Nunns, of the University of Exeter Medical School, said: "The mental health of children and young people is important and offering the best response is vital. When we set out to do this research we were hoping to make recommendations about what works to support children and young people with long term conditions, who are also having difficulties with their mental health. However, we were disappointed in the lack of good quality evidence available to guide treatment decisions for these children."

Throughout the study, the team worked with a group of children and young people who provided a real-world perspective on the issues they face. They were particularly disappointed in the lack of available research and urged researchers to do something about it. This sentiment was echoed by consultant paediatrician Professor Stuart Logan: 'The two things that are needed alongside managing a medical condition like this are something to help the family manage and something to help with the children's emotional problems that so often go alongside these medical conditions. The exciting thing about this project is that it provides researchers with a roadmap for what to do next - we need to work sensibly with parents and children to carefully design treatments and test them in a way that helps us understand whether they actually work."

The systematic review will be published in Health Technology Assessment. The full title of the paper is: Interventions to improve the mental health of children and young people with long-term physical conditions: linked evidence syntheses.

Lithium Doesn't Crack Under Pressure, It Transforms
by ALIYAH KOVNER

Using cutting-edge theoretical calculations performed at NERSC, researchers at Berkeley Lab's Molecular Foundry have predicted fascinating new properties of lithium - a light alkali metal that has intrigued scientists for two decades with its remarkable diversity of physical states at high pressures.

"Under standard conditions, lithium is a simple metal that forms a textbook crystalline solid. However, scientists have shown that when you put a lithium crystal under pressure, the atomic structure changes and, somewhat counterintuitively, its conductivity drops, becoming less metallic," said Stephanie Mack, a graduate student research assistant at Berkeley Lab and first author of the study, published in PNAS. "We've discovered it also becomes topological, with electronic properties similar to graphene."

Topological materials are a recently discovered class of solids that display exotic properties, such as having insulating interiors yet highly conductive surfaces, even when deformed. They are exciting for potential applications in next-generation electronics and quantum information science. According to co-authors Sinéad Griffin and Jeff Neaton, lithium becomes topological at high but experimentally achievable pressures, comparable to one-quarter of the pressure at the Earth's center.

Thus far, most experimentally verified topological materials contain heavy, potentially toxic, elements. "But we've predicted that lithium, ostensibly a simple metal, can also have these unique properties," said Mack.

A 'Silver Bullet' for the Chemical Conversion of Carbon Dioxide
By Lori Tamura

Fossil fuels are the lifeblood of modern societies, but their increased use releases carbon dioxide, a climate-warming greenhouse gas, faster than plants can recycle it via photosynthesis.

Now, a powerful combination of experiment and theory has revealed atomic-level details about how silver helps transform carbon dioxide gas into a reusable form. The results, reported in the journal Nature Communications, will help in the design of more efficient metal catalysts.

"Before, people always thought that the process was the same on all metals," said Berkeley Lab researcher Yifan Ye, one of the study's authors. "But now, we have discovered that there are other options for reactions. This is new chemistry, and it's a new reaction pathway."

Metals such as silver facilitate the transformation (or "reduction") of carbon dioxide into carbon monoxide (CO), which is used to synthesize other useful chemicals. The work revealed a surprising first step in this process that hadn't been seen nor suggested before. Ultimately, the researchers hope to optimize carbon dioxide catalysis by using additives or metal alloys.

The work involved a close collaboration between theorists from Caltech and experimentalists from Berkeley Lab's Advanced Light Source, working together under the umbrella of the Joint Center for Artificial Photosynthesis, a Department of Energy Energy Innovation Hub.

Read the full story here.

Media contact: Laurel Kellner, LKellner@lbl.gov, 510-590-8034

Understanding Microbiomes for Advanced Wastewater Treatment and Reuse Systems
JULIE CHAO

Wastewater is treated by an activated sludge process in municipal wastewater treatment plants and returned to the environment for use. This treatment process has been used for over a century, and today represents the largest application of biotechnology in the world, yet there has been no effort to map the global activated sludge microbiome.

A study recently published in Nature Microbiology reports the first comprehensive, highly coordinated effort to examine the global diversity and biogeography of this microbiome. "The campaign involved 111 investigators who sampled 269 wastewater treatment plants in 86 cities in 23 countries on six continents," said Jizhong Zhou, a professor of microbiology at the University of Oklahoma and Berkeley Lab adjunct senior scientist.

The researchers found a highly diverse activated microbiome, containing up to one billion microbial phylotypes comprised of novel species. "This expansive study is the first time that a systematic study of the hugely beneficial microbial communities involved in the biological treatment of daily wastewaters from communities around the world have been studied to understand their fundamental structure and function has been undertaken. It represents an important development in understanding and maintaining these crucial microbial communities," said Lisa Alvarez-Cohen, a co-author and adjunct senior scientist at Berkeley Lab.

Read the full release from the University of Oklahoma here.

To learn more about Berkeley Lab's water-energy research, visit the site of our Water-Energy Resilience Research Institute.

DURHAM, N.C. -- A new Duke University-led study finds that the death of marsh plants due to disturbances like the heavy oiling from the Deepwater Horizon oil spill can double the rate of shoreline erosion in hard-hit marshes.

"The results from our field experiment unequivocally show that the loss of wetland vegetation increases the rate of erosion on wave-stressed shorelines by 100%," said Brian R. Silliman, Rachel Carson Professor of Marine Conservation Biology at Duke's Nicholas School of the Environment.

"These findings are going to make it hard for oil companies whose spills kill marsh grasses or mangroves on the edge of coastal wetlands to say that the loss of plants due to heavy oiling doesn't have a long-term effect," he said.

Some industry-sponsored scientists have theorized that the increased erosion of Louisiana marshes following the 2010 Deepwater Horizon spill didn't stem from the spill itself. They say that Hurricane Katrina, which struck the coast five years earlier, was already causing the marshes to erode faster and that plant loss from the oil spill played a negligible role.

"Our study refutes that claim," Silliman said. "We're not saying that soil type and hurricane-driven wave action don't affect marsh-edge erosion rates too, but our findings clearly show that the loss of plant roots compounds everything else and accelerates erosion even further."

Silliman and his colleagues published their peer-reviewed paper May 23 in Current Biology.

To test the competing theories, they conducted a three-year field experiment at salt marsh sites in Florida with similar soils, vegetation and wave exposure as marshes that were hit by the Deepwater Horizon spill.

The researchers divided the sites into test plots of different sizes and subjected plots of each size to three different treatments. In some plots, they repeatedly cut the plants' stems down to the ground but left the roots intact. In other plots, they used herbicide to kill the plants, roots and all. Other plots were left unaltered to serve as controls where researchers could measure the base rate of erosion caused by wave action.

"In plots where we just cut off the stems, no extra erosion over the base rate occurred because the roots were still there to help hold things together. But in plots where we killed the roots too, the amount of land loss increased by 100 percent," Silliman said.

"The size of the test plot didn't matter. Wherever we started killing roots, that's where erosion started happening," he said.

An analysis of other recent peer-reviewed studies on marsh erosion corroborated the team's findings and confirmed that the amount of land loss in an affected marsh is directly proportional to the amount of root loss.

"These small-scale experiments confirmed what we found in large-scale observational studies across hundreds of kilometers of heavily oiled marshes in Louisiana following the Deepwater Horizon spill," Silliman said. "If a disturbance like heavy oiling kills the roots, increased erosion occurs. The more roots killed, the more erosion. And because the eroded area is much lower in elevation and is flooded continuously, the plants can't grow back. The land has been converted into sea."

"Coastal wetlands offer protection from storm surges and other extreme weather and climate events," said David Garrison, a program director in the National Science Foundation's Division of Ocean Sciences, which funded the research. "This paper is an important step in understanding the resilience of these important ecosystems."

Various sources have estimated that between 15,000 and 24,000 acres of Gulf Coast salt marshes experienced plant stem oiling above a 90% threshold as a result of the Deepwater Horizon spill. Previous research led by Silliman has shown that 90% is the tipping point at which root death occurs and recovery is no longer possible.

"Given the vital roles coastal salt marshes play in protecting shorelines from erosion and flooding, providing habitat for wildlife and helping clean our water, we need to better understand the thresholds of salt marsh resilience to human disturbances like oil," Silliman said.

Professional football players appear to have a somewhat elevated risk of death, including higher risk of succumbing to cardiac and neurodegenerative diseases, compared with professional baseball players of similar age, according to new research.

The findings raise important questions about sport-specific differences in disease development and the mechanisms that drive the elevated risk. Such mechanisms mandate further research, the investigators said.

This particular study was not designed to elucidate the reasons for the elevated risk seen in NFL players, nor was it intended to examine the mechanisms that fuel disease development in these athletes, the investigators caution.

The analysis--the first head-to-head comparison between elite professional athletes of similar ages--is published May 24 in JAMA Network Open. The work was conducted by investigators at the Harvard T.H. Chan School of Public Health, Harvard Medical School and Spaulding Rehabilitation Hospital.

The findings are based on a retrospective analysis of death rates and causes of death in 3,419 NFL (National Football League) and 2,708 MLB (Major League Baseball) players over more than 30 years.

There were 517 deaths among NFL players and 431 deaths among MLB players between 1979 and 2013. The difference translates into a 26 percent higher mortality among football players compared with baseball players. NFL players had a nearly threefold greater likelihood of dying of neurodegenerative conditions, compared with MLB players. They also had a nearly 2.5-fold risk of dying from a cardiac cause, the study showed. There were 498 deaths stemming from cardiovascular causes among the NFL players and 225 such deaths among MLB players. The study identified 39 deaths from neurodegenerative conditions such as Alzheimer's disease, ALS and Parkinson's in NFL players and 16 such deaths in MLB players. There were 11 suicides among the NFL group and five in the MLB group.

Extrapolating these differences into absolute numbers, the researchers said, the elevated risk would translate into one additional death from a neurodegenerative disease per 1,000 NFL players by age 55 rising to 11 additional neurodegenerative deaths by age 75, compared with MLB players. Cardiovascular causes would account for 16 additional deaths per 1,000 NFL players by age 55 and rising to 77 additional deaths by age 75 in NFL players, compared with MLB players.

"Even a single preventable or premature death is one too many, so it is critical for scientists and clinicians to pursue further research into teasing out the reasons behind this increased mortality," said study senior author Marc Weisskopf, the Cecil K. and Philip Drinker Professor of Environmental Epidemiology and Physiology at the Harvard Chan School. "However, it is important to remember that the actual number of additional deaths from neurodegenerative diseases among football players remains low."

The number of excess deaths (77) stemming from cardiovascular illness was markedly higher, which may be due to several factors, including higher body-mass index among football players and the sheer prevalence of cardiovascular illness, the researchers said. Indeed, cardiovascular disease is the leading cause of death in the United States and worldwide.

The results point to the existence of sport-specific differences in sport-related injuries and athlete conditioning as important contributors to disease development. For example, head trauma, repetitive head injuries and subconcussive blows in NFL athletes may contribute to the onset of pathologies that eventually lead to certain neurologic conditions, the researchers said. Football players' larger overall size and greater body-mass index, which renders them more susceptible to hypertension and sleep apnea, can also be contributors, the researchers added.

For their analysis, the researchers used vital statistics obtained from two national databases--the National Institute for Occupational Safety and Health for information on NFL players and the Lahman Baseball Database of MLB players, an index combining data on MLB and predecessor leagues no longer in existence. The researchers then cross-referenced death outcomes from these two databases with information obtained from the National Death Index, a federal database that tracks causes of death occurring within the United States.

Past research has compared health status and mortality outcomes between professional football players and the general population, but such comparisons are inherently flawed because football players are overall healthier than members of the general population. Past comparisons between NFL players and the general population have showed a lower overall mortality rate among football players but an increased risk for death from neurologic disease.

In a somewhat more meaningful comparison, a recent study analyzed death outcomes among NFL players and replacement football players who played during an NFL players' strike. This research found a small but statistically insignificant increase in death rates among NFL players.

A comparison between two groups of professional athletes with similar physical characteristics, levels of conditioning and overall health status can tease out more meaningful differences in risk directly attributable to playing one sport versus the other, the investigators said.

Understanding whether and how certain sport-specific activities may fuel the development of diseases is essential to informing appropriate interventions, the researchers said.

"A life in pro football may have lifelong consequences, particularly in the domains of cardiac and neurologic health," said Ross Zafonte, the Earle P. and Ida S. Charlton Professor and head of the Department of Physical Medicine and Rehabilitation at Harvard Medical School.

"Elucidating sports-specific aspects of disease development is critical for our ability to inform best strategies to maintain optimal player health and prevent disease," Zafonte added. "This study illuminates the importance of former players taking an active step in seeking a comprehensive health evaluation from their doctor. They should ensure they are closely monitored for both cardiovascular and neurological issues, some of which may be treatable."