Earth

AMHERST, Mass. - In a new study out this week, a team including forest ecologist Malcolm Itter at the University of Massachusetts Amherst reports finding "clear evidence of a contraction of the breeding period" among boreal birds in Finland over a 43-year span for which good quality data were available.

The study was run by researchers within the Research Centre for Ecological Change (RCEC) at the University of Helsinki, led by Maria Hällfors with Itter and Laura Antão, all postdoctoral researchers at the time. They were joined by additional researchers at the Swedish University of Agricultural Sciences and the Finnish Museum of Natural History. Details appear in Proceedings of the National Academy of Sciences.

Itter says that for most of the 73 species studied, "we saw an advance in the beginning of the breeding period," an average 4.6 days, and the breeding period ending earlier, an average of 6.3 days. The average breeding period contracted by 1.7 days over the period with a breeding period contraction in roughly 31 percent of all species.

The researchers report that "this pattern was most common among resident and short-distance migrating species." This suggests that residents and short-distance migrants "may be better able to respond to increased temperatures in the spring and thus take better advantage of the earlier food and resource availability," while "long-distance migrants that arrive later may not be able to do so," Itter explains.

This study is unusual, as researchers looked not only at the onset of the breeding period, but also its end, and duration. They used "unique and extensive long-term bird-banding data" collected over 43 breeding seasons by a small army of experienced, dedicated banders - called ringers in Europe. Tits, thrushes, crows, owls and gulls showed the greatest changes in breeding period. "Any species that had a contraction had an earlier end to the breeding season," Itter notes.

The authors state, "Our findings highlight the importance of quantifying phenological change across species and over the entire season to reveal shifts in the community-level distribution of bird reproduction." And, "most importantly, our study suggests that evaluating changes throughout the season is crucial, as earlier and shorter breeding periods in birds may alter community-wide patterns of species co-occurrence and trophic relations across the boreal region."

Hällfors, Itter and colleagues' main hypothesis was that as conditions warm, they should see food and other resources become available earlier in the year, and because temperature is the cue for favorable conditions to rear chicks, warmer springs may cause the breeding period to shift forward.

They used a creative combination of techniques for data analysis, including a modeling framework developed for natural community data and primarily to predict species' range shifts. The model framework was applied in this case to jointly estimate changes in the breeding period of a boreal bird community - breeding beginning, end and duration.

The model included evolutionary history information; the study found that species that shared evolutionary history shared similar breeding shifts. "From a methodological perspective, our study illustrates that a focus on quantifying phenological advances alone may mask important patterns of phenology change across the season," authors note

Itter says the team expected to see differences in breeding period linked to distinct ecological zones across a latitudinal gradient in Finland, but found instead that "ecological zone didn't seem to matter, changes in the beginning, duration and end of breeding did not vary strongly by ecological zone for a given species."

DALLAS - July 23, 2020 - Deleting a key gene in mice in just their fat made tissues throughout these animals insulin resistant, in addition to other effects, a new study by UT Southwestern researchers shows. The findings, reported in a recent issue of PNAS, could shed light on Type 2 diabetes and other insulin resistance disorders, which remain poorly understood despite decades of study.

In 2016, UTSW immunologist and geneticist Bruce Beutler, M.D., Zhao Zhang Ph.D., and their colleagues reported a new mouse mutant that they named teeny, which resulted from inactivating a gene known as KBTBD2 that is widely expressed throughout the body in mice and humans. In addition to these animals' small size - about half that of normal "wild type" mice - the scientists quickly noticed that teeny mice produce a lot of urine, often a sign of diabetes.

Beutler is a regental professor and director of the Center for the Genetics of Host Defense. Zhang is an assistant professor of internal medicine who also has an appointment in the center.

Sure enough, tests showed that these animals had extremely high blood sugar, severe insulin resistance, and high insulin levels that peaked at 8 weeks of age and then gradually declined. They also had abnormally low amounts of body fat but had fatty livers. Transplanting teeny mice with fat tissue from normal mice largely resolved these problems, a sign that KBTBD2 in fat tissue in particular is key to each of them. However, say Beutler and Zhang, it was unclear whether these problems were also rooted in KBTBD2 activity in other insulin-responsive tissues, such as muscle and liver.

To answer this question, the researchers created different mouse mutants in which KBTBD2 was selectively inactivated in the animals' fat, muscle, or liver. Although each of these rodents grew to a normal size - suggesting that this gene acts through other pathways to regulate body growth - only those with KBTBD2 inactivated in fat cells had some other hallmark characteristics of teeny. These animals had extremely high insulin resistance, although only moderately high blood sugar levels. Although their blood insulin levels were also high, they didn't decline after 8 weeks of age as in teeny mice.

In addition to having abnormally low body fat like their teeny counterparts, those animals missing KBTBD2 in just their fat cells also had fatty livers, suggesting communication between fat and liver tissue.

Together, say Beutler and Zhang, the findings confirm that KBTBD2 plays a key role in regulating insulin sensitivity and a variety of other activities through its role in fat. However, they also raise important questions about what this gene does elsewhere in the body. KBTBD2 produces a protein that slices up another protein known as p85a, part of a larger protein complex that encourages insulin-sensitive cells to produce sugar transporters on their surfaces. Although it clearly performs this job when produced in fat cells, it doesn't seem to do this in other parts of the body even though it's widely expressed in other cell types. It is also unclear what part KBTBD2 plays in keeping teeny mice so small. The researchers plan to explore these questions in future studies.

They also plan to investigate the mechanisms behind why these animals have such extreme insulin resistance, which could have implications for Type 2 diabetes in humans, a disease marked by this characteristic.

"Although we know that insulin resistance is very rarely caused by mutations in the insulin receptor or genes responsible for making other proteins known to participate in glucose uptake, most of it is not understood," says Beutler, a Nobel Laureate. "Getting a better grasp on the function of KBTBD2 could open a completely new window into how insulin sensitivity is regulated."

Beutler, who developed a technology for instantly identifying induced germline mutations that cause phenotypes in mice, received the Nobel Prize in Physiology or Medicine in 2011 for his discovery of an important family of receptors that allow mammals to sense infections when they occur, triggering a powerful inflammatory response. He holds the Raymond and Ellen Willie Distinguished Chair in Cancer Research, in Honor of Laverne and Raymond Willie, Sr.

Rising ocean temperatures have devastated coral reefs all over the world, but a recent study in Global Change Biology has found that reefs in the Eastern Tropical Pacific region may prove to be an exception. The findings, which suggest that reefs in this area may have adapted to heat stress, could provide insights about the potential for survival of reefs in other parts of the world. The study was published in print in July.

"Our 44-year study shows that the amount of living coral has not changed in the ETP," said James W. Porter, the paper's senior author. "Live coral cover has gone up and down in response to El Niño-induced bleaching, but unlike reefs elsewhere in the Caribbean and Indo Pacific, reefs in the ETP almost always bounce back," he said.

The study was conducted by an international team of researchers from across the region led by Dr. Mauricio Romero-Torres of the Pontificia Universidad Javeriana and Unidad Nacional para la Gestión del Riesgo de Desastres (the National Unit for Disaster Risk Management or UNGRD) in Bogotá, Colombia. The group examined coral cover data for the area, which stretches from Baja California to the Galapagos Islands, from 1970-2014. During that time there were several El Niño events--periods when the equatorial Pacific Ocean reaches unusually high temperatures. Excessive heat can kill the symbiotic algae that inhabit the corals, leading to widespread coral bleaching and death.

The researchers found that while losses of coral cover followed the worst of those episodes, in many cases ETP reefs recovered within 10-15 years.

"So much of my career has been spent documenting coral reef decline that to discover a large area of the tropics where coral reefs are holding their own is very gratifying," said Porter, professor emeritus in the University of Georgia Odum School of Ecology.

They hypothesized that several key factors allowed the ETP reefs to bounce back.

First, corals in this area are mostly pocilloporids, a type of coral that reproduces at high rates. They also contain species of symbiotic algae that are particularly tolerant to extreme temperatures.

Patterns of weather and geography in the ETP may also play a role. Areas having heavier cloud cover or upwelling of cooler waters may survive locally and be able to reseed more severely affected reefs elsewhere.

Another important factor may be "ecological memory," meaning that ETP corals may have become conditioned to heat stress over the years, through mechanisms such as genetic adaptation and epigenetic inheritance, whereby parents pass on these survival traits to their offspring.

"The key to survival for future reefs may not be an immunity to stress, but rather an ability to recover and regrow after stress," said Porter. "ETP reefs show us what this might look like."

Porter said that the study is also important as an example of the need for maintaining long-term original data, which was crucial to the research.

"As soon as Dr. Romero contacted me, I consulted my original dive logs, made when I was a Smithsonian Pre-Doctoral Fellow in Panama in 1970," said Porter. "I realized immediately that my hand-written field notes contained everything needed to anchor this study with the oldest data (1970) used in this long-term survey. Particularly in a changing world, we need to archive and store original data carefully," he said. "Knowing what the world looked like in the past may be the best way to set restoration goals in the future."

"This research teaches the relevance of doing science with FAIR standards (findable, accessible, interoperable and reusable) so that other researchers in the region can continue the work and estimate the effects of the next El Niño phenomenon on the ETP," said Romero.

Throughout the world's oceans in global nutrient cycles, food chains, and climate, as well as increasingly in human-made industrial processes, a diverse set of planktonic microbes, such as algae, play an integral role. For nearly all of these planktonic microbes, however, little is known about them genetically beyond a few marker sequences, while their morphology, biological interactions, metabolism, and ecological significance remain a mystery.

Algae produce half of the oxygen in earth's atmosphere and some forms of algae are used in industrial applications -- such as producing high omega-3 fatty acids for baby formula or being used for biofuels -- so there are many reasons a better understanding of algae could be beneficial. There is another side to algae, however, as some species can create harmful algal blooms (HABs), and those have been the focus of the research of University of Delaware's Kathryn Coyne.

Advancing the study of microbes

To help advance the understanding of the cellular instructions that underpin microbial life in the sea, Coyne joined more than 100 scientists from institutions around the globe to publish a compilation of methods, or protocols, for laboratory experiments that will help scientists gain a better understanding of the genetic underpinnings of marine algae as a resource article in the journal Nature Methods.

The work was funded by the Gordon and Betty Moore Foundation's Marine Microbiology Initiative. For her contribution to the collaboration, Coyne worked specifically with Heterosigma akashiwo, a species of algae that can produce HABs.

One of the mysteries about H. akashiwo is that while some strains produce toxins that can kill fish, other strains are non-toxic.

"We don't have a clear understanding of what kind of toxin they produce. We just know that when there are blooms of this algae in some areas of the world, they are associated with massive fish kills," said Coyne, an associate professor of marine biosciences in UD's College of Earth, Ocean, and Environment (CEOE), and director of the Delaware Sea Grant program. "We also don't know why some strains produce toxins, or what stimulates this toxin production."

Scientists often use genome manipulation to better understand how microbes respond to the environment or to identify genes that may be involved in a specific response, like production of toxins. Unlike other algal species that serve as models for genome manipulations, however, H. akashiwo doesn't have a cell wall, instead having only a thin membrane that holds the cell shape. Coyne explained that having a cell wall can be an impediment to genome manipulations and that these kinds of experiments usually entail some effort initially just to remove the cell wall or make it more porous.

Because H. akashiwo lacked a cell wall, Coyne and her research team proposed that genome manipulation might be more straightforward with this species, and were able to demonstrate that using a couple of gene manipulation methods that have been successful on other model species.

"We created a piece of genetic material that could be introduced into Heterosigma cells that would make them resistant to a specific antibiotic," said Coyne. "If we were successful, we would be able to grow them in this antibiotic and cells that had incorporated the resistance gene would survive."

Coyne worked with Deepak Nanjappa, a postdoctoral researcher in her lab who is also an author on the paper, as well as Pam Green and her lab members, Vinay Nagarajan, a postdoctoral researcher, and Monica Accerbi, a research associate in Green's lab at the Delaware Biotechnology Institute (DBI).

Together, they tried a handful of methods and optimized those that were successful for Heterosigma. One method in particular was replicated successfully several times, showing that they were able to produce a genetically modified strain of Heterosigma. Using this approach, scientists can now probe the genome of Heterosigma akashiwo to gain a better understanding of how this species responds to environmental cues, or what genes are responsible for its toxicity.

One of the aims of the project was to make all of the methods developed freely available so that scientists can take that information and use it in their own research.

"The Moore Foundation funded this project with the expectation that all of the methods developed during this research would be published," said Coyne. "Nothing is proprietary for this project, so we can share any of the protocols that we developed for Heterosigma."

Immobilizing algicidal bacteria

In addition, Coyne had another paper published in the scientific journal, Harmful Algae, that detailed her work with Yanfei Wang, a doctoral student in CEOE, studying the algicidal bacterium Shewanella and how it could be used to remediate HABs.

Shewanella, which is an algicidal bacterium that has been isolated from the Delaware Inland Bays, is being developed as a biological control for HABs. It secretes water-soluble compounds that inhibit the growth of dinoflagellates, single-celled organisms that often produce toxins and contribute to HABs. Other research on this species of Shewanella shows that it has no negative effects on the growth of other species of algae, or on fish or shellfish. Since it was isolated from local waters, it may be considered an "environmentally neutral" solution to controlling HABs.

In order to use Shewanella in the natural environment to control HABs, there first needs to be a method to safely deploy the bacterium in areas that are at risk for HABs.

To move this HAB control solution closer to reality, Coyne and Wang immobilized Shewanella into several porous materials. Funded by Delaware Sea Grant, this research determined how well each material retained the bacteria over time, and whether the immobilized form of Shewanella was effective at controlling the growth of dinoflagellates.

Unlike other HAB control approaches, such as application of toxic chemicals like copper sulfate, the advantage of using immobilized algicidal bacteria is the potential for continuous control of HABs without the need for frequent reapplication. The immobilized bacteria can also be removed when it is no longer needed.

This research found that an alginate hydrogel was the most successful of the porous materials used in the study, and had the best retention of Shewanella cells.

This research also showed that Shewanella cells immobilized in alginate beads were as effective as free bacteria in controlling the growth of the harmful species while at the same time having no negative impacts on a non-harmful control species.

Overall, the study suggests that immobilized Shewanella may be used as an environmentally friendly approach to prevent or mitigate the blooms of harmful dinoflagellates and provides insight and directions for future studies.

Cancer's knack for developing resistance to chemotherapy has long been a major obstacle to achieving lasting remissions or cures. While tumors may shrink soon after chemotherapy, many times they eventually grow back.

Scientists once thought that unique genetic mutations in tumors underlay this drug resistance. But more and more, they are casting their eyes on other, nongenetic changes in cancer cells to explain their adaptability.

For example, one way that cancer cells can develop resistance is by changing their identity. A prostate cancer cell that is sensitive to hormone-blocking therapy might morph into a cell type that does not require the hormone for its growth.

Rather than specific mutations driving them, identity changes like these come about through changes in gene expression -- cells turning specific genes on or off. As a result of these changes, a single tumor can become very different in its cellular makeup. This heterogeneity creates challenges for treatment, since a single drug is unlikely to work against so many different cell types.

A new study from a team of researchers at the Sloan Kettering Institute, the Koch Institute for Integrative Cancer Research at MIT, and the Klarman Cell Observatory at the Broad Institute finds that this tumor heterogeneity can be traced to a common source: a particularly flexible cell state that is characteristic of a subset of cells in a tumor and can generate many other diverse cell types.

"The high-plasticity cell state is the starting point for much of the heterogeneity we see in tumors," says Tuomas Tammela, an Assistant Member in the Cancer Biology and Genetics Program at SKI and the corresponding author on the new paper, published July 23 in the journal Cancer Cell. "It's kind of like a busy intersection of many roads: Wherever a cell wants to end up identity-wise, it has to go through this cell state."

Because this cell state produces nearly all the cellular heterogeneity that emerges in tumors, it is an attractive target for potential therapies.

The particular tumors the researchers examined were lung cancer tumors growing in mice. Jason Chan, a physician-scientist doing a fellowship in the Tammela lab and one of the paper's lead authors, says finding this unusual cell state was a surprise.

"This highly plastic cell state is something completely new," he says. "When we saw it, we didn't know what it was because it was so different. It didn't look like normal lung cells where the cancer came from, and it didn't really look like lung cancer either. It had features of embryonic germ layer stem cells, cartilage stem cells, and even kidney cells, all mixed together."

Nevertheless, he and his colleagues found these cells in every tumor they examined, which suggested that the cells were doing something biologically very important.

A Cell State Road Map

The researchers identified these highly plastic cells by employing a relatively new laboratory technique called single cell RNA sequencing (scRNA-Seq). This technique allows researchers to take "snap shots" of individual cells' gene expression profiles -- revealing which genes are on or off. By performing scRNA-Seq on tumors as they grew over time, they were able to watch when and how different cell types emerged over the course of a tumor's evolution. From these data, the researchers were able to create a kind of map of which cells came from which other cells.

"The map contains major highways and little dirt roads," Dr. Tammela says. "The high-plasticity cell state that we identified sits right in the middle of the map. It has a lot of paths coming in, and it has even more paths coming out."

This high-plasticity cell state emerged consistently in a tumor's evolution and persisted throughout its growth. In fact, Dr. Tammela says, "it was the only cell state that we found to be present in every single tumor."

Not Stem Cells

Plasticity -- the ability of a cell to give rise to other cells that take on different identities -- is a well-known feature of stem cells. Stem cells play important roles in embryonic development and in tissue repair. Many scientists think that cancers arise from specific cancer stem cells.

But Dr. Tammela and colleagues do not think these high-plasticity cells are stem cells.

"When we compare the gene expression signature of these highly plastic cells to normal stems cells or known cancer stem cells, the signatures don't match at all. They look completely different," he says.

And unlike stem cells, they're not there at the very beginning of a tumor's growth. They only emerge later.

Changing to Resist Drugs

Many prior studies have looked for possible "resistance mutations" -- genetic changes that account for a tumor's ability to resist the effects of cancer drugs. While some have been found, more often the basis of resistance remains a mysterious. The new findings offer a potential solution to the mystery.

"Our model could explain why certain cancer cells are resistant to therapy and don't have a genetic basis for that resistance that we can identify," Dr. Chan says.

Importantly, it's not all the cells in the tumor that are adapting, he explains. It's a subset of the cancer cells that are just more plastic, more malleable.

By combining chemotherapy drugs with new medications that target these highly plastic cells, the researchers think it might be possible to avert the emergence of resistance and provide longer lasting remissions.

GAINESVILLE, Fla. --- Scientists have described a new native Hawaiian land snail species, sounding a rare, hopeful note in a story rife with extinction.

Pacific island land snails are among the world's most imperiled wildlife, with more recorded extinctions since 1600 than any other group of animals. Hawaii's once-teeming land snail scene of more than 750 species has shrunk by more than half, ravaged by habitat loss and invasive species such as rats, Jackson's chameleons and the carnivorous rosy wolf snail.

Auriculella gagneorum, a small candy-striped snail from Oahu's Waianae Mountains, represents the first new species of a living Hawaiian land snail described in 60 years. The species "brings that little glimmer of hope that this isn't all a depressing story," said the study's lead author Norine Yeung, malacology curator at the Bishop Museum.

A team of researchers found A. gagneorum during a large-scale, decade-long survey of land snails that spanned 1,000 sites throughout the Hawaiian Islands. They then used the Bishop Museum's collection of land snails to match individuals collected during the survey to unidentified specimens from the 1940s.

"This is a happy story where we discovered a snail that is still around," Yeung said. "There are so many things in our collection that we can no longer find in the wild. But in this snail's case, we can finally put a name to it and describe it, which is huge for the conservation of this species."

The tree-dwelling snail shows pronounced variation in coloring, from burnished tiger's-eye patterning to dramatic sable and white stripes. At less than two-tenths of an inch long, "you might be able to fit a dozen on your fingernail," said study co-author John Slapcinsky, collection manager of invertebrate zoology at the Florida Museum of Natural History.

Land snails play a crucial role as decomposers and fungivores in Hawaii's ecosystems, essentially "our first recyclers," Yeung said.

The researchers deposited a selection of A. gagneorum snails in Hawaii's captive breeding program, with the goal of increasing their numbers and returning them to the wild. They named the species in honor of the late Hawaiian naturalists Betsy and Wayne Gagne, who were "powerhouses for conservation," Yeung said. "They cared about the whole ecosystem, whether it was a tiny little bug or plants or one of Hawaii's charismatic, beautiful forest birds."

The team's survey also produced new records of three snail species last documented in the 1950s and others feared extinct, as well as nearly 30 new species. The researchers failed to find two species, A. auricula and A. minuta, whose populations may have died out.

But while the status of Hawaii's land snails is dire, it's too early to despair, said Slapcinsky, who gamely struggled through skin-ripping raspberry thickets and nearly slid off a cliff while sieving for snails.

"People used to think it wasn't even worth studying Hawaiian land snails because they were all extinct. Now we know they're not," he said. "If we work at it, there's still a chance to do something about it. That's why it's important to be out there surveying, finding the remaining populations of these species."

Yeung said previous reports estimated that 90% of Hawaii's land snails were extinct, but the team's survey shows that about 300 species still survive in remote, isolated parts of the Hawaiian Islands.

"The challenge now is trying to identify all of these because we have lost a lot of experts, and a lot of these snails are super tiny," she said. "If you're not a trained malacologist, the small brown snails might all look the same to you. But when you take a closer look at their shells, bodies and genetics, these little things are all different and can be tied to different valleys and ridges. When one species turns out to be three, we can run into problems with conservation."

The researchers used a combination of physical characteristics and DNA to describe the new species. While its shell size and shape mimic A. perpusilla snails from the Koolau Range on east Oahu, molecular evidence shows A. gagneorum is more closely related to A. tenella, a slender, high-spired snail from the Waianae Range in the west.

A. gagneorum belongs to a long-overlooked group of snails known as Auriculellinae. The majority of attention and conservation efforts have focused on the larger, more colorful snails in the subfamily Achatinellinae, Lonesome George, the last known snail of its species, being the most famous example. While an entire genus of Achatinellinae is listed under the Endangered Species Act, the smaller, less obvious snails in the subfamily Auriculellinae remain understudied and unprotected, Slapcinsky said.

"We're not bemoaning that Achatinellinae are getting attention. They do need help," he said. "What we're concerned about is that these other things are getting ignored."

Meanwhile, the team pushes forward in its analysis of a decade's worth of data and many new species descriptions. Afterwards, the researchers can turn their attention to the evolution and ecology of Hawaii's land snails, traditionally considered by native Hawaiians as important symbols and good omens that represent change, romance and song.

"The diversity is amazing, the species are amazing, and there are so many evolutionary stories you could tell," Yeung said, describing malacology as a "wide-open frontier."

"But first we have to identify these snails. If you ask about their habitat and life history, it's like, I wish I could tell you. Right now, I can just tell you this is a different species and put a name on it. It's hard work, but it's so gratifying."

ITHACA, N.Y. - Small farms in Zambia that use the latest hybrid seed for maize, along with improving health on neutral soils, help reduce deforestation and tackle climate change, Cornell University researchers report this month in Global Environmental Change.

"Scientists around the world are trying to reduce rapid deforestation and food insecurity, especially in the tropics," said Johanne Pelletier, a postdoctoral researcher in the Charles H. Dyson School of Applied Economics and Management and the paper's lead author.

"Smallholder farmers are a cornerstone of food security in the world," Pelletier said. "The main driver of deforestation is agricultural expansion in Africa, South America and Asia. It is important to learn what works at improving food security and keeping forests standing."

Pelletier conducted this work as part of the NatureNet Science Fellows Program, a joint research project funded by the Cornell Atkinson Center for Sustainability and The Nature Conservancy. She works in the research group led by Chris Barrett, the Stephen B. and Janice G. Ashley Professor at Dyson.

"There are synergies to using a modern hybrid seed and good agronomic techniques to maintain healthy soils with stopping the degradation of tropical forests and halting climate change," said Barrett, the paper's senior author.

"Promoting improved maize seed uptake among smallholder farmers - which Zambia and many other governments do - is not only boosting yield, but it is reducing pressure on large forests," Barrett said. "This is good news."

Zambia has about 44 million hectares of forests that are dominated by the Miombo Woodland, an ecological region that is home to a diverse population of wildlife. The total mass of the forests has substantially dwindled since 2000: Zambia lost more than 1.3 million forested hectares between 2000 and 2012, which is referenced in the paper. A hectare is approximately 2.5 acres.

The Zambian government is looking at ways to reduce national deforestation.

"If we can produce more food per hectare with better seed, and by improving soil health," Pelletier said, "we can protect those much-needed forests."

DURHAM , N.C. -- Strategic networking is key to career success, and not just for humans. A new study of wild bottlenose dolphins reveals that in early life, dolphins devote more time to building connections that could give them an edge later on.

Researchers at Georgetown University and Duke University report that dolphins under age 10 seek out peers and activities that could help them forge bonds and build skills they'll need in adulthood.

The results were published July 14 in the journal Behavioral Ecology.

The team analyzed nearly 30 years' worth of records for more than 1700 wild bottlenose dolphins in Shark Bay in Western Australia. Since the 1980s, researchers have been taking boats out into this remote bay and noting things like the sex, age and behavior of any dolphins they encountered.

For the current study, the team focused on data collected on youngsters from weaning to age 10, looking at who they hung out with and how they spent their time when no adults were around.

Around 3 or 4 years old, dolphins leave the protection of their mothers to venture off on their own, living in ever-changing groups that come together, split up and come together again in different combinations.

The study revealed that, even though young dolphins flit from group to group as often as every ten minutes throughout the day, they tend to spend more time with a few close friends.

These companions aren't just friends because they share the same areas of water and bump into each other more often, the research shows. "These relationships reflect true preferences," said first author Allison Galezo, a biology Ph.D. student in professor Susan Alberts' lab at Duke.

Males prefer to hang out with other males; females with other females. But the researchers observed that males and females tend to interact in different ways. Males were more likely than females to spend their time together resting or engaged in friendly physical contact: rubbing flippers, swimming close together and mirroring each other's movements. Whereas females socialized less often, and instead spent twice as much time as their male counterparts foraging for fish.

These differences suggest that the social lives of young dolphins may be shaped by the upcoming demands of adulthood, Galezo said.

For adult males, having other males in their corner is key to have a chance at passing on their genes. In Shark Bay, groups of two to three male dolphins often join forces to get fertile females alone with them and coerce them to mate. By the time they grow up, males will need to have enough social savvy to build and maintain strong alliances, or lose out on their chance to get a girl.

Being a successful adult female, on the other hand, means caring for calves that aren't weaned until they're at least three years old. Nursing moms need more calories, and so young females may spend more time foraging to practice skills they'll need later on, before the full realities of motherhood set in.

"The juvenile period can be an opportunity to develop social skills that will be important in adulthood, without the high-stakes risks that go with sexual maturity," Galezo said.

The most advanced and comprehensive analysis of climate sensitivity yet undertaken has revealed with more confidence than ever before how sensitive the Earth's climate is to carbon dioxide.

For more than 40 years, the estimated likely range of the eventual global temperature response to a doubling of atmospheric carbon dioxide compared to preindustrial levels has stubbornly remained at 1.5°C - 4.5°C.

This new research, revealed in a 165 page, peer-reviewed journal article commissioned by the World Climate Research Programme (WCRP) written over four years, finds that the true climate sensitivity is unlikely to be in the lowest part of the 1.5-4.5°C range. The analysis indicates that if atmospheric carbon dioxide levels double from their pre-industrial levels and are maintained, the world would probably experience eventual warming from 2.3 - 4.5°C. The researchers found there would be less than 5% chance of staying below 2°C and a 6-18% chance of exceeding 4.5°C.

With the Earth's temperature already at around 1.2°C above preindustrial levels, if greenhouse gas emissions trajectories continue unabated the world can expect to see a doubling of carbon dioxide in the next 60-80 years.

"Narrowing the range of climate sensitivity has been a major challenge since the seminal US National Research Council paper came up with a 1.5 - 4.5°C range in 1979 (Charney et al). That same range was still quoted in the most recent IPCC report," said lead author Prof Steven Sherwood, a University of New South Wales chief investigator with the ARC Centre of Excellence for Climate Extremes.

The research was only made possible by bringing together an international team of researchers from a wide range of climate disciplines. Using temperature records since the industrial revolution, paleoclimate records to estimate prehistoric temperatures, satellite observations and detailed models that examine the physics of interactions within the climate system the team were able to combine more independent lines of evidence than any previous study to get their results.

These lines of evidence were then combined in a statistically rigorous way allowing the team to find where the results overlapped. This allowed them to converge on the best estimate of climate sensitivity. The team found that, with new developments, the various lines of evidence corroborated one another leading to more confidence in the result. The 2.3-4.5°C range accounts cautiously for alternative views or assumptions and "unknown unknowns," with a more straightforward calculation yielding an even narrower 2.6-3.9°C likely range.

"This paper brings together what we know about climate sensitivity from measurements of atmospheric processes, the historical warming, and warm and cold climates of the past. Statistically combined, these estimates make it improbable that climate sensitivity is at the low end of the IPCC range and confirm the upper range. This adds to the credibility of climate model simulations of future climate," said co-author Gabi Hegerl from the University of Edinburgh.

"An important part of the process was to ensure that the lines of evidence were more or less independent," said Prof Sherwood. "You can think of it as the mathematical version of trying to determine if a rumour you hear separately from two people could have sprung from the same source; or if one of two eyewitnesses to a crime has been influenced by hearing the story of the other one."

The researchers then went another step further and identified the conditions that would be required for the climate sensitivity to lie outside this most likely range.

The researchers show that low climate sensitivities previously thought to be plausible, around 1.5-2C, could only occur if there were multiple unexpected and unconnected errors in the data analysis (for example unexpected cloud behaviour and patterns of long-term ocean warming), underlying their judgment that these low values are now extremely unlikely.

A different set of circumstances make it unlikely that global temperatures would rise more than 4.5°C for a doubling of carbon dioxide from pre-industrial times, although these higher temperature responses are still more likely than very low sensitivities.

Even with this qualification, the three-year long research process initiated by the WCRP with double-checking at every step, a detailed examination of the physical processes and an understanding of the conditions required for the estimate has finally consolidated an advance on the 40-year-problem.

"These results are a testament to the importance of cross-disciplinary research along with slow, careful science and perfectly highlight how international co-operation can unpick our most vexing problems," said co-author Prof Eelco Rohling from the Australian National University.

"If international policymakers can find the same focus and spirit of co-operation as these researchers then it will give us hope that we can forestall the worst of global warming."

New research into graphene flakes has discovered that the material can act as a surfactant, for the first time demonstrating how it can be a versatile 2D stabiliser ideal for many industrial applications from oil extraction to paper processing.

Pristine graphene is completely water repellent, but the researchers found that at a particular size (below 1-micron lateral size), amphiphilic behaviour is possible. This graphene flake attracts water at its edges but repels it on its surface, making it a new generation of surfactant that can stabilise oil and water mixtures.

Krzysztof Koziol, Professor of Composites Engineering and Head of the Enhanced Composites and Structures Centre at Cranfield University said, "This new finding, and clear experimental demonstration of surfactant behaviour of graphene, has exciting possibilities for many industrial applications. We produced pristine graphene flakes, without application of any surface treatment, at a specific size which can stabilise water/oil emulsions even under high pressure andhigh temperature . Unlike traditional surfactants which degrade and are often corrosive, graphene opens new level of material resistance,can operate at high pressures, combined with high temperatures and even radiation conditions; and we can recycle it. Graphene has the potential to become a truly high-performance surfactant."

The qualities of this graphene flake make it an ideal material to be combined with water and used as a surfactant in environmently friendly extraction of minerals, crude oil and other ores from rock. There is also need for better quality surfactants as plasticisers for fluid concrete, additives in flameroofing and waterproofing as well as lubricants in drilling fluids to improve effectiveness of drilling operations.

The surfactants currently in use are corrosive and degrade under intense heat and pressured environments. Graphene offers a more stable, cost-effective and environmentally friendly way to operate in harsh geological or chemical environments.

Mike Payne, Professor of Computational Physics at Cambridge University, who was one of the co-researchers for this project, said: "There is an enormous volume of scientific research on graphene. In some ways this is to be applauded but it can also lead to conflicting results in the literature - as in the present example of whether graphene flakes are hydrophobic or amphiphilic. Our work combines exciting experiments on well characterised material with a range of theoretical simulations, including quantum mechanical calculations. Together they provide a detailed understanding of the properties of the graphene flakes and a definitive answer to this question."

The COVID-19 pandemic has thrown up unimaginable challenges for healthcare workers. Even simple outpatient procedures such as endoscopies can expose staff to the risk of infection.

However, a team of researchers has developed a simple, disposable, and inexpensive device to provide an additional barrier of protection for healthcare workers performing esophagogastroduodenoscopies (EGD).

An EGD is an endoscopic procedure by which a doctor examines a patient's esophagus, stomach, and upper intestines. The procedure causes patients to cough or retch, exposing workers to body fluids or aerosol droplets.

Given that COVID-19 is easily spread via air-borne transmission, researchers from the
gastroenterology departments at the Tohoku University Graduate School of Medicine and the Japan Community Health Care Organization's Sendai Hospital set out to create a device capable of catching droplets without causing further discomfort to the patient.

The new device comprises a mouthpiece equipped with a fixing belt and a nonwoven fabric to cover the patient's face, thereby capturing aerosol droplets.

The square, nonwoven fabric is attached to the tips of the mouthpiece using symmetric cuts made by scissors. An x-shaped incision at the center of the fabric acts as a sleeve for the endoscope--providing minimal interference.

Special care was taken in choosing the fabric. Having a tight enclosure would exposure patients to respiratory stress and risk choking if vomiting. The nonwoven fabric maintains high elasticity and air permeability, providing minimal discomfort for the patient.

"This device is expected to capture the coarse droplets from subjects undergoing an EGD and to reduce the diffusion of aerosol droplets," exclaimed Doctor Hiroyuki Endo, the corresponding author of the paper. "In addition to existing personal protective equipment, this simple and inexpensive device can be used as a standard precaution in every EGD."

The 'Gamma Factory initiative' - an international team of scientists - is currently exploring a novel research tool: They propose to develop a source of high-intensity gamma rays using the existing accelerator facilities at CERN. To do this, specialized ion beams will be circulated in the SPS and LHC storage rings, which will then be excited using laser beams so that they emit photons. In the selected configuration, the energies of the photons will be within the gamma radiation range of the electromagnetic spectrum. This is of particular interest in connection with spectroscopic analysis of atomic nuclei. Furthermore, the gamma rays will be designed to have a very high intensity, several orders of magnitude higher than those of systems currently in operation. In the latest issue of the journal Annalen der Physik, the researchers claim that a 'Gamma Factory' constructed in this way will enable not only breakthroughs in spectroscopy but also novel ways of testing fundamental symmetries of nature.

At the heart of the Gamma Factory proposal are special ion beams made of heavy elements such as lead that have been stripped of almost all the electrons in the outer shell. A lead atom normally has 82 protons in the nucleus and 82 electrons in its shell. If only one or two electrons are left, what results are so-called 'partially stripped ions' - PSIs for short. In the prospective Gamma Factory setting, they will circulate in a high-energy storage ring, such as the Super Proton Synchrotron (SPS) or the Large Hadron Collider (LHC) at CERN.

PSIs offer unique opportunities for researching various fundamental questions in modern science. In atomic physics they serve as a kind of mini-laboratory to investigate how systems with few electrons behave when they are exposed to strong electromagnetic fields - which, in the case of PSIs, are produced by the atomic nuclei themselves.

The main concept underlying of the Gamma Factory is to make a laser beam collide head-on with an accelerated PSI beam. In the 'PSI laboratory', the incident photons can generate excited states by transporting electrons to higher orbits - this constitutes an ideal test system that will facilitate detailed investigations using atomic spectroscopy (primary beam spectroscopy). In turn, the PSIs excited by the laser beam themselves emit photons, which can then be used in numerous other experiments "outside" the PSI laboratory (secondary beam spectroscopy). The resultant gamma ray beam will be characterized by high energies of up to 400 megaelectron volts, which corresponds to a wavelength of 3 femtometers. By way of comparison, the photon energy of visible light is eight orders of magnitude smaller, with a correspondingly greater wavelength.

"The Gamma Factory that we are proposing offers two immensely exciting prospects: On the one hand, it will be a very intense light source which produces high energy gamma rays at a very specific band of frequencies; at the same time it will act as a giant ion trap where we can use spectroscopy to get a very accurate picture of the PSIs circulating in the storage ring," explains Prof. Dmitry Budker from the PRISMA+ Cluster of Excellence of University Mainz and the Helmholtz Institute Mainz and one of the authors of the recent publication. "In our article, we describe the many possibilities offered by the two approaches. On the other hand, it is important to address the current and future challenges associated with establishing a Gamma Factory like this."

Examples of exciting physics applications of primary beam spectroscopy include measurement of the effects of atomic parity violation in PSI - the result of weak interactions among subatomic particles - as well as detection of the distribution of neutrons in the nuclei of the PSI. The information thus obtained would complement some of the most important research activities being carried out in Mainz. The secondary, high energy gamma ray beams with precisely controlled polarization can be used in conjunction with 'fixed' polarized targets, for example, in order to investigate the structure of atomic nuclei as well as nuclear reactions relevant to astrophysics. The secondary gamma rays can also be used to generate intense tertiary beams, for example, those of neutrons, muons or neutrinos.

A variety of technological challenges will have to be overcome to ensure the optimal operation of the Gamma Factory. "So, for example, we need to learn to perform laser cooling of ultrarelativistic PSI in order to reduce their energy spread and obtain a well-defined beam," points out Dmitry Budker. "Whilst the laser cooling of ions at lower energies has already been investigated, at GSI in Darmstadt for example, it has not yet been performed at such high energies as those that will be associated with the Gamma Factory."

The Gamma Factory at CERN is no longer just a pipe dream, because in July 2018, major progress was made from concept to reality. The Gamma Factory group together with the CERN accelerator experts managed to make beams of hydrogen- and helium-like lead ions circulate in the SPS for several minutes. The hydrogen-like beam was later injected into the LHC, where it then circulated for several hours. "The next crucial step is running the dedicated proof-of-principle experiment at CERN's SPS that will hopefully validate the entire Gamma Factory concept," concludes Dmitry Budker, outlining the exciting next stage. The Gamma Factory is an ambitious proposal, currently being explored within the CERN 'Physics beyond Colliders' program.

Various forms of mercury are released naturally by volcanoes and weathering of rocks and soil. Human activities, such as mining or burning fossil fuels, can also release the element into the environment, where aquatic microbes can convert it into the toxic form, methylmercury. Now, researchers reporting in ACS' Environmental Science & Technology have shown that dragonfly larvae, collected from national parks as part of a citizen-scientist engagement program, can serve as sentinels for mercury bioaccumulation.

High levels of methylmercury can cause cardiovascular and neurological problems in people and impair reproduction in fish and other wildlife. Sentinels are organisms used to detect risks to humans from environmental hazards. So, by monitoring total mercury and methylmercury levels in sentinels, scientists can have an early warning system for when levels get dangerously high. But finding an ideal sentinel for monitoring mercury nationwide has been tricky -- the same fish or aquatic birds are not found at every body of water, and collecting these animals for analysis can raise logistical, regulatory and ethical concerns. Collin Eagles-Smith and colleagues wondered if dragonfly larvae would be good sentinels. These bugs live in diverse freshwater habitats across the globe, and methylmercury accumulates in their tissues. They are also relatively easy to collect and identify, making them suitable for citizen science.

From 2009 to 2018, more than 4,000 citizen-scientists helped collect almost 15,000 dragonfly larvae from more than 450 sites in 100 national parks across the U.S. The researchers analyzed the samples for total mercury and a subset of samples for the methyl form. Elevated total mercury concentrations were found at several parks, but the levels in dragonfly larvae varied by more than a hundredfold among different sites. Mercury concentrations were higher in larvae from rivers and streams than in larvae from lakes and ponds, and larvae from water bodies that were surrounded by wetlands had much higher concentrations than larvae from water bodies that weren't. The mercury concentrations correlated with those in fish and amphibians at the same locations -- enabling development of a tool to predict mercury in other species using dragonfly larvae. About 12% of the places sampled had mercury levels that were considered high and potentially detrimental to fish, wildlife or human health, the researchers say.

Philadelphia, July 22, 2020 - Researchers in Spain propose mitigating methane production by dairy cattle through breeding. In an article appearing in the Journal of Dairy Science, scientists are targeting reduction of enteric methane in the breeding objectives for dairy cattle to select for animals that use feed more efficiently and thus produce less methane. Because livestock farming contributes 13 percent of global greenhouse gas (GHG) emissions, selective breeding can reduce those emissions while increasing milk output.

Methane from enteric fermentation is considered the main contributor to GHG coming from ruminants. These emissions contribute to global warming and represent a loss of dietary energy in ruminants. "Current selection pressure is increasing total methane production in the population of dairy cows but is reducing methane intensity (per kilogram of milk) due to higher productive levels of each cow. A reduction of methane in the breeding goals should also be included in the selection indices," said lead author Oscar González-Recio, PhD, Department of Animal Breeding, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Madrid, Spain.

Evaluation of the genetic traits and economic response of the traits in the selection index were considered in this study that used genetic parameters estimated with 4,540 records from 1,501 cows. The project was funded by the Spanish National Plan of Research, Development, and Innovation 2013-2020. While methane production is necessary to maintain rumen homeostasis, total methane emissions are expected to decrease four to six percent in 10 years due to increased milk production per cow. If annual methane production per cow is included in breeding goals and ad hoc weights are placed on methane production, GHG emission from cattle could be reduced by 20 percent in 10 years.

Dr. González-Recio added that "increasing per-cow productivity may reduce the number of cows needed per billion kilograms of milk produced, contributing to mitigation of GHG emissions, but this is not enough. If no action is taken, the genetic potential for methane production is expected to increase."

While the biological limit of methane production remains unknown, this study shows the potential for including environmental traits in selection indices while retaining populations of cows that are profitable for producers.

(Edmonton, AB) A team of University of Alberta researchers has developed a faster way of tracking the movement of tumours in the body during radiation therapy, which could significantly improve outcomes for cancer patients.

"When a patient is getting radiation treatment, for example on the lungs, the tumour might be moving because of the patient's breathing," said Michelle Noga, a U of A radiologist who also works at MIC Medical Imaging and is the study's co-author.

"We normally have to radiate a bigger area than the actual tumour to account for that movement. So the idea is that if you could track their breathing and adjust the beam to match that, you wouldn't have to radiate such a big area and potentially damage healthy tissue."

The team's work builds on the Linac-MR project, a radiation beam (linear accelerator or "linac") and magnetic resonance imaging (MRI) hybrid machine developed by researchers at the Cross Cancer Institute in 2013.

As patients lie in the machine, the MRI provides constant imaging of the tumour, allowing the system to track its movement and keep the radiation focused only on that area. However, real-time tracking requires significant processing power and the current approach is too slow for day-to-day use, said the study's lead researcher, Kumaradevan Punithakumar.

"The original version of the tracking algorithm runs through the computer's central processing unit, but it can only handle eight or 12 processes at a time. That's too slow for real-time tracking," he said. "So we adapted the algorithm to use the graphics processing unit (GPU), which can handle thousands of processes at once."

The U of A team--which included medical physicists Jihyun Yun and Gino Fallone, and computing scientists Nazanin Tahmasebi and Pierre Boulanger--found the GPU processing increased the speed of the process by five times.

"These are very good results," said Punithakumar, who, along with Noga, is also a member of the Women and Children's Health Research Institute. "Improving the computational performance has been an issue for a number of imaging applications, and we've done that.

"We are also seeing improved tracking accuracy [over] previous methods. So the combination of improved performance and accuracy is a very, very good result."

Punithakumar notes that although the algorithm was applied to the Linac-MR system in this specific study, it could be used for similar medical imaging applications or other organ delineation tasks, such as cardiac ventricle segmentation using MRI.

For now, the next steps include fully integrating the algorithm into the Linac-MR system, then running more tests to ensure it consistently works as expected, Punithakumar said. Then, the team hopes to be able to move on to clinical testing.

"In the future, this could be completely automated," Punithakumar said. "The patient will come in, move into the machine, and the machine will be able to determine which area to target and provide that information to the oncologist. Once the oncologist confirms the target, then the system starts the radiation therapy, adjusting to any movement in real time automatically."