Earth

Researchers from the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) of the Chinese Academy of Sciences have found a new species of sandgrouse in six to nine million-year-old rocks in Gansu Province in western China. The newly discovered species points to dry, arid habitats near the edge of the Tibetan Plateau as it rose to its current extreme altitude.

According to their study published in Frontiers in Ecology and Evolution on Mar. 31, the new species, named Linxiavis inaquosus, fills a nearly 20 million-year gap in the sandgrouse fossil record.

The fossil of the partial skeleton includes much of the body, such as the shoulder girdles, wishbone, bones from both wings, vertebrae, and part of a leg. Unfortunately, the head is missing.

"As the oldest fossil of a sandgrouse in Asia and the most complete fossil known from the group, the new skeleton provides a key link in expanding our understanding of the evolution of the sandgrouse living in China today, as well as the ecosystem associated with the Tibetan Plateau and the species that live only there," said Dr. LI Zhiheng, first author of the study.

Sandgrouse are a group of 16 species of birds related to doves and pigeons that live in some of the most arid areas across Europe, Asia, and Africa. The association between sandgrouse and dry environments has helped scientists determine that the area next to the Tibetan Plateau was equally arid when Linxiavis inaquosus lived during the period known as the late Miocene.

"Most people would probably think of the Tibetan Plateau, with its high elevation, low oxygen levels, and harsh sun as one of the last places to be invaded by a group of animals. But in this case, our fossil suggests that sandgrouse might have quickly adapted to the dry, mountainous plateau millions of years ago," said the coauthor Dr. Thomas A. Stidham.

Importantly, this fossil is from the time period known as the late Miocene when the Tibetan Plateau was continuing to rise rapidly in altitude and changing the climate of central Asia with an increase in aridity, along with a strong monsoon season.

This fossil was found at over 2,000 meters above sea level and within sight of Tibetan Plateau peaks that exceed 4,000 meters. That elevation is far greater than where all species of sandgrouse, except for the specialized Tibetan Sandgrouse, live today.

Despite the elevation and arid conditions, other fossils from the area show that the ecosystem was quite diverse. Dr. Stidham explains, "If you were on the edge of the Tibetan Plateau where our fossil is from six or seven million years ago, it would have looked quite like a nature documentary about the savannas in Africa, with the horizon filled with extinct relatives of hyenas, elephants, rhinos, pigs, antelopes, horses, ostriches, vultures, falcons, and of course now, sandgrouse."

"We are discovering many fossil birds in this area by the Tibetan Plateau that help us to understand the relationships between the plateau, climate change, and biodiversity. We're likely to keep uncovering more unusual and amazing bird fossils like this sandgrouse and the pheasant with a windpipe longer than its body that we reported a couple of years ago," said Dr. LI.

Image-and-text health warning labels, similar to those on cigarette boxes, show potential for reducing the consumption of alcoholic drinks and energy-dense snacks, such as chocolate bars, according to a study published in the open access journal BMC Public Health.

Health warning labels (HWLs) using images and text to depict the negative health consequences of smoking have been found to be effective and acceptable for changing smoking-related outcomes. However, evidence for the potential usefulness of HWLs for reducing the consumption of alcoholic drinks and energy-dense foods like chocolate bars or crisps, is limited.

A team of researchers at the Universities of Cambridge and Bristol, UK conducted two online studies with separate participants, asking them to rate different image-and-text HWLs on alcoholic drinks (5,528 participants) or energy-dense snacks (4,618 participants).

Dr Gareth Hollands, the corresponding author said: "To our knowledge, these are the first large-scale studies in general populations to examine the potential effectiveness and acceptability of image-and-text health warning labels on alcohol and on snack foods. Prior research in this area has typically either looked at these warning labels on sugary drinks, or used smaller or less representative samples."

The authors found that HWLs on alcoholic drinks depicting bowel cancer, followed by those depicting liver cancer were associated with the highest level of negative emotions - such as fear, disgust, discomfort and worry - and the lowest desire to consume the product. They were also considered the least acceptable for use by the study participants. In general, few of the alcohol HWLs were considered acceptable, with only three out of 21 rated at least somewhat acceptable.

HWLs on high-density snacks depicting bowel cancer, followed by those depicting non-specific cancer were associated with the highest level of negative emotions and lowest desire to consume the product, with those depicting bowel cancer considered to be the least acceptable. HWLs on energy-dense snacks were judged on average more acceptable than those on alcohol, with 13 out of 18 snack HWLs rated as at least somewhat acceptable.

The authors suggest that the response to labels depicting bowel cancer HWLs may indicate those that have the greatest potential for reducing alcohol and snack food selection and consumption.

Gareth Hollands said: "The finding that health warning labels may be judged to be relatively more acceptable to use on snack foods, than on alcohol, could be due to heightened public awareness of the health consequences of excess energy intake and obesity, particularly in children. In general, however, many of the participants expressed negative views of the possible use of such labels."

Participants for the alcohol study were sampled from the UK population if they self-reported consuming either beer or wine at least once a week. A total of 5528 people were shown an image of a bottle of beer or wine labelled with one of 21 possible HWLs illustrating the adverse health consequences of alcohol consumption. Participants were asked how afraid, worried, uncomfortable or disgusted the label made them feel, to rate their desire to consume the product, and how strongly they supported putting the label on alcoholic drinks.

For the food study participants were sampled from the UK population if they self-reported that they consumed biscuits, cake, crisps or chocolate at least once a week, and liked chocolate. A total of 4618 people were shown an image of a chocolate bar labelled with one of 18possible HWLs illustrating the adverse health consequences of obesity and related conditions, caused by excess calorie consumption.

The authors caution that this study could not demonstrate whether negative emotional arousal and impacts on desire to consume are actually effective in changing behaviour. As the studies were conducted online, responses may differ when HWLs are applied to physical products in real-world settings. Further studies are needed to examine the real-world potential of these labels to reduce selection and consumption of alcohol and energy-dense snacks.

Tumours in infants biologically distinct from older patients

Study finds genetic vulnerabilities to existing targeted drugs

Clinical trials to offer hope for families of youngest patients

Brain cancer in infants is biologically distinct from other childhood brain tumours and could be successfully treated with targeted drugs, a new study has shown.

An aggressive type of brain tumour, called high-grade glioma, is almost always fatal in older children - with only 20 per cent surviving for more than five years.

Babies and very young children, diagnosed when they are less than 12 months old, tend to have a better outcome - with around two thirds surviving five years or more.

In the largest and most comprehensive study of infant gliomas to date, scientists found that these tumours are molecularly different from those in older children, helping explain why they tend to be less aggressive.

The new results could help pick out babies with brain tumours who could be spared chemotherapy - which can have devastating side-effects and be particularly harmful while their brain is still developing.

The study found that brain tumours in babies often had specific molecular weaknesses which could be targeted by existing targeted drugs - and clinical trials to assess these are now set to open.

Scientists at The Institute of Cancer Research, London, carried out a large-scale study of 241 infants from around the world diagnosed with glioma brain tumours - working with colleagues at the Hopp Children's Cancer Center Heidelberg in Germany, the UCL Great Ormond Street Institute of Child Health, and St. Jude Children's Research Hospital in the US.

The researchers found that 130 of the 241 tumour samples - or 54 per cent - had an entirely different genetic make-up from other forms of childhood brain tumours, despite looking highly similar under the microscope.

Some 65 cases, or half of children with the distinct form of infant brain tumours, had specific molecular weaknesses - including ALK and NTRK gene fusions, which can be targeted with existing precision medicines.

The study is published in Cancer Discovery today (Thursday), and was funded by charities including the CRIS Cancer Foundation, The Brain Tumour Charity, Children with Cancer UK, Great Ormond Street Hospital Children's Charity, and Cancer Research UK.

Next, the team looked at mice with brain tumours caused by ALK gene fusions to compare the effect of a targeted drug, lorlatinib, which works by blocking ALK, with temozolomide chemotherapy.

They found that lorlatinib significantly shrunk tumours in seven out of eight mice, or 88 per cent, while tumours in mice given chemotherapy kept growing, though at a slower rate.

The researchers also grew three-dimensional 'mini tumours' in the lab from patient samples, and found those that had fusions of NTRK with other genes were particularly sensitive to drugs blocking NTRK. Tumours with these fusion mutations were between two and nine times more sensitive to the targeted treatments entrectinib, crizotinib and milciclib than those without.

A small number of children whose tumours were analysed in the study were successfully treated with ALK or NTRK targeting drugs, offering further evidence for the promise of targeted treatments for infant brain tumours.

Clinical trials are due to open to test the benefit of targeted drugs blocking the ALK and NTRK gene fusions in infant brain tumours - and to better understand the biology of tumours which don't have these faults.

The new results are also set to change the World Health Organization's diagnostic guidelines, with brain tumours in infants to be classed separately from other childhood brain tumours.

Professor Chris Jones, Professor of Paediatric Brain Tumour Biology at The Institute of Cancer Research, London, said:

"We found that glioma brain tumours in babies are biologically completely different to those in older children, even though under the microscope they look much the same.

"Our study offers the biological evidence to pick out those infants who are likely to have a better outcome from their disease, so these very small children and their families can be spared the harmful effects of chemotherapy.

"We showed that brain tumours in infants have particular genetic weaknesses that could be targeted with existing drugs - and clinical trials are planned to test the benefit of these precision medicines as a first-line treatment in clinical trials as soon as possible."

Dr Matthew Clarke, Clinical Research Fellow in the Glioma Team at The Institute of Cancer Research, London, said:

"Brain tumours that arise in the very youngest children tend to have better outcomes from those in older children - and our new study explains that difference on a biological level.

"Chemotherapy is currently a good treatment option for babies with brain tumours - but our study has found that some children could be spared this treatment. With further testing, I'm hopeful that existing targeted drugs could expand our arsenal of options to treat these smallest of patients."

Professor Paul Workman, Chief Executive of The Institute of Cancer Research, London, said:

"It's especially cruel when cancer affects such small children, so it is encouraging that this study offers some hope for very young patients and their families. The research offers a better understanding of the biology of brain tumours in infants, and finds that they might potentially be treated with new targeted drugs. That's vitally important because infants are particularly vulnerable to the side effects from standard treatments such as chemotherapy, and we need much better, kinder options."

For the first time in more than a century, Vermont and neighboring states are losing forestland to development at a rate of almost 1,500 acres per year. As forest fragmentation gains ground across the New England landscape, where private ownerships and small land parcels are the norm, conserving land for future generations of people, wildlife, and plants becomes more necessary but more difficult.

Vermont is a third of the way there. In a new study, forest conservation experts at the University of Vermont (UVM) confirmed that the state has already protected 33%, or 1.3 million acres, of highest priority targeted lands needed to protect and connect valuable wildlife habitats and corridors.

Most of the currently conserved lands are forested, yet not nearly enough of the state's highest priority targeted surface water and riparian areas - ponds, rivers, shorelines, and wetlands - are protected. Many animals require zones along waterways in which to travel between habitats they need to survive.

The researchers scrutinized Vermont's new state-level vision for conservation, Vermont Conservation Design, meant to create physical pathways for movement of animals and plants across the landscape, especially in a future of changing climate. They compiled a database of Vermont's conserved lands and overlaid them with the state's highest priority landscape targets.

"The State of Vermont and a number of partners have laid out an impressive, thoughtful vision to ensure that Vermont remains a good place for all forms of life in the future," said Carolyn Loeb, a graduate student in the UVM College of Agriculture and Life Sciences' Field Naturalist Program who led the study. "Our goal was to answer the questions: how far have we come, what successes and gaps do we see so far in fulfilling the design, and where do we go from here?"

The study, "Large landscape conservation in a mixed ownership region: Opportunities and barriers for putting the pieces together," was published in the journal Biological Conservation in March 2020 with free online access until April 18, 2020.

Of Vermont's protected land, the authors found that 87% of those acres, or 22% of the state's total land base, are also considered highest priority by Vermont Conservation Design targets.

"Our research indicates that past conservation efforts in Vermont really matter, even though our reasons and perspectives around conservation have evolved," said Loeb.

Historically, forest conservation targeted high elevation settings--think summit of Vermont's Camel's Hump. The study found that the state has adequately conserved higher elevation lands that are also design targets, but lower elevation targets remain a gap among protected areas.

"Vermont is at a critical juncture in conserving the wild and working forest landscapes of the state, as we observe losses in forest cover to development and other land uses," said Tony D'Amato, a professor in the UVM Rubenstein School of Environment and Natural Resources. "This study provides a crucial benchmark of current levels of forest protection to help prioritize future conservation actions to achieve the impressive vision Vermont Conservation Design has outlined for sustaining the ecological, economic, and social benefits of Vermont's forests into the future."

Across all 1.5 million acres of Vermont's currently conserved lands, three groups dominate in responsibility for the most protected lands: the national government, the state, and private nonprofit organizations, which can also conserve lands on behalf of other private landowners.

The public sector of national and state government each hold responsibility for 30.5% of protected lands, which include the U.S. Forest Service's Green Mountain National Forest, other federal lands, and the Vermont state parks, forests, and wildlife management areas. The Vermont Department of Forests, Parks and Recreation protects the most design-targeted lands of any state agency.

Nonprofit organizations have responsibility for 35.4% of protected lands, while town and tribal entities hold responsibility for 3.6% and 0.01% of conserved lands, respectively.

While public agencies are responsible for most of the highest priority forested area targets in Vermont, nonprofit organizations have protected the largest percentage of highest priority riparian and surface water targets. Nonprofits, such as the Vermont Land Trust and The Nature Conservancy in Vermont, through conservation easements, have played a unique role in protecting these wetlands and waterways. But the study underscores that there are still notable gaps in protecting low elevation and riparian lands identified in the design as very important.

"Going forward, Vermont's nonprofits will play an increasingly important role in land conservation, especially in continuing to protect those areas that are rich with species diversity," said Elizabeth Thompson, Director of Conservation Science at Vermont Land Trust. "Nonprofits are engaging more and more deeply in restoring wetlands that were previously degraded, planting new forests along river shores to slow flood waters and provide wildlife habitat, and protecting unique natural communities while also protecting working forests and farmland."

The authors recommend continued support for collaboration between public and private partners in land conservation, planning for quick response to large and potentially unexpected land sales that are important design targets, increased assistance for nonprofits in gaining protections for under-represented surface waters and connected riparian area targets, and a greater focus on protection of low-elevation targeted lands in Vermont by turning to strategies for better connecting the small ownership, patchworked landscapes that occur in much of the state.

A partial skeleton of Homo naledi represents a rare case of an immature individual, shedding light on the evolution of growth and development in human ancestry, according to a study published April 1, 2020 in the open-access journal PLOS ONE by Debra Bolter of Modesto Junior College in California and the University of the Witwatersrand, Johannesburg, and colleagues.

Much research has gone into the evolution of ancient hominins - human relatives and ancestors - but little is known about their growth and development. Most hominin fossils represent adult individuals, and remains of developmentally young hominins are rare. This has left a gap in our understanding of how our ancient relatives grew from young into adults, and how modern human growth patterns evolved.

In this study, Bolter and colleagues examined fossils from the Dinaledi Chamber of the Rising Star Cave System in South Africa. This site is famous for providing abundant remains of the hominin Homo naledi, including individuals ranging from infants to adult. These fossils date to the late Middle Pleistocene, between 335,000 and 226,000 years ago, possibly overlapping in time with the earliest members of our own species. The team identified a collection of arm and leg bones and a partial jaw as the remains of a single young individual designated DH7.

The bones and teeth of DH7 were not fully developed and display a mixture of maturity patterns seen in modern humans and earlier hominins. DH7 is estimated to be similar in its developmental stage to immature specimens of other fossil hominins between 8-11 years old at death. The authors note, however, that if Homo naledi had a slower growth rate like modern humans, DH7 might have been as old as 15. Further study is needed to assess how Homo naledi grew and where it fits into the evolution of human growth and development.

Bolter adds: The rare juvenile Homo naledi partial skeleton will shed light on whether this extinct species is more human-like in its development, or more primitive. The findings help reconstruct the selective pressures that shaped extended maturity in our own species.

Scientists have long been able to measure and analyze the fossil skulls of our ancient ancestors to estimate brain volume and growth. The question of how these ancient brains compare to modern human brains and the brains of our closest primate cousin, the chimpanzee, continues to be a major target of investigation.

A new study published in Science Advances used CT-scanning technology to view three-million-year old brain imprints inside fossil skulls of the species Australopithecus afarensis (famous for "Lucy" and "Selam" from Ethiopia's Afar region) to shed new light on the evolution of brain organization and growth. The research reveals that while Lucy's species had an ape-like brain structure, the brain took longer to reach adult size, suggesting that infants may have had a longer dependence on caregivers, a human-like trait.

The CT-scanning enabled the researchers to get at two long-standing questions that could not be answered by visual observation and measurement alone: Is there evidence for human-like brain reorganization in Australopithecus afarensis, and was the pattern of brain growth in this species more similar to that of chimpanzees or that of humans?

To study brain growth and organization in A. afarensis, the researchers, including ASU paleoanthropologist William Kimbel, scanned eight fossil crania from the Ethiopian sites of Dikika and Hadar using high-resolution conventional and synchrotron-computed tomography. Kimbel, leader of the field work at Hadar, is director of the Institute of Human Origins and Virginia M. Ullman Professor of Natural History and the Environment in the School of Human Evolution and Social Change.

Lucy's species inhabited eastern Africa more than three million years ago--"Lucy" herself is estimated to be 3.2 million years old--and occupies a key position in the hominin family tree, as it is widely accepted to be ancestral to all later hominins, including the lineage leading to modern humans.

"Lucy and her kin provide important evidence about early hominin behavior--they walked upright, had brains that were around 20 percent larger than those of chimpanzees, and may have used sharp stone tools," explains coauthor Zeresenay Alemseged (University of Chicago), who directs the Dikika field project in Ethiopia and is an International Research Affiliate with the Institute of Human Origins.

Brains do not fossilize, but as the brain grows and expands before and after birth, the tissues surrounding its outer layer leave an imprint on the inside of the bony braincase. The brains of modern humans are not only much larger than those of our closest living ape relatives but are also organized differently and take longer to grow and mature. Compared with chimpanzees, modern human infants learn longer and are entirely dependent on parental care for longer periods of time. Together, these characteristics are important for human cognition and social behavior, but their evolutionary origins remain unclear.

The CT scans resulted in high-resolution digital "endocasts" of the interior of the skulls, where the anatomical structure of the brains could be visualized and analyzed. Based on these endocasts, the researchers could measure brain volume and infer key aspects of cerebral organization from impressions of the brain's structure.

A key difference between apes and humans involves the organization of the brain's parietal lobe--important in the integration and processing of sensory information--and occipital lobe in the visual center at the rear of the brain. The exceptionally preserved endocast of "Selam," a skull and associated skeleton of an Australopithecus afarensis infant found at Dikika in 2000, has an unambiguous impression of the lunate sulcus--a fissure in the occipital lobe marking the boundary of the visual area that is more prominent and located more forward in apes than in humans--in an ape-like position. The scan of the endocranial imprint of an adult A. afarensis fossil from Hadar (A.L. 162-28) reveals a previously undetected impression of the lunate sulcus, which is also in an ape-like position.

Some scientists had conjectured that human-like brain reorganization in australopiths was linked to behaviors that were more complex than those of their great ape relatives (e.g., stone-tool manufacture, mentalizing, and vocal communication). Unfortunately, the lunate sulcus typically does not reproduce well on endocasts, so there was unresolved controversy about its position in Australopithecus.

"A highlight of our work is how cutting-edge technology can clear up long-standing debates about these three million-year-old fossils," notes coauthor Kimbel. "Our ability to 'peer' into the hidden details of bone and tooth structure with CT scans has truly revolutionized the science of our origins."

A comparison of infant and adult endocranial volumes also indicates more human-like protracted brain growth in Australopithecus afarensis, likely critical for the evolution of a long period of childhood learning in hominins.

In infants, CT scans of the dentition make it possible to determine an individual's age at death by counting dental growth lines. Similar to the growth rings of a tree, virtual sections of a tooth reveal incremental growth lines reflecting the body's internal rhythm. Studying the fossilized teeth of the Dikika infant, the team's dental experts calculated an age at death of 2.4 years.

The pace of dental development of the Dikika infant was broadly comparable to that of chimpanzees and therefore faster than in modern humans. But given that the brains of Australopithecus afarensis adults were roughly 20 percent larger than those of chimpanzees, the Dikika child's small endocranial volume suggests a prolonged period of brain development relative to chimpanzees.

"The combination of apelike brain structure and humanlike protracted brain growth in Lucy's species was unexpected," says Kimbel. "That finding supports the idea that human brain evolution was very much a piecemeal affair, with extended brain growth appearing before the origin of our own genus, Homo."

Among primates, different rates of growth and maturation are associated with different infant-care strategies, suggesting that the extended period of brain growth in Australopithecus afarensis may have been linked to a long dependence on caregivers. Alternatively, slow brain growth could also primarily represent a way to spread the energetic requirements of dependent offspring over many years in environments where food is not always abundant. In either case, protracted brain growth in Australopithecus afarensis provided the basis for subsequent evolution of the brain and social behavior in hominins and was likely critical for the evolution of a long period of childhood learning.

LOWELL, Mass. - A discovery by a team of researchers led by UMass Lowell nuclear physicists could change how atoms are understood by scientists and help explain extreme phenomena in outer space.

The breakthrough by the researchers revealed that a symmetry that exists within the core of the atom is not as fundamental as scientists have believed. The discovery sheds light on the forces at work within the atoms' nucleus, opening the door to a greater understanding of the universe. The findings were published today in Nature, one of the world's premier scientific journals.

The discovery was made when the UMass Lowell-led team was working to determine how atomic nuclei are created in X-ray bursts - explosions that happen on the surface of neutron stars, which are the remnants of massive stars at the end of their life.

"We are studying what happens inside the nuclei of these atoms to better understand these cosmic phenomena and, ultimately, to answer one of the biggest questions in science - how the chemical elements are created in the universe," said Andrew Rogers, UMass Lowell assistant professor of physics, who heads the research team.

The research is supported by a $1.2 million grant from the U.S. Department of Energy to UMass Lowell and was conducted at the National Superconducting Cyclotron Laboratory (NSCL) at Michigan State University. At the lab, scientists create exotic atomic nuclei to measure their properties in order to understand their role as the building blocks of matter, the cosmos and of life itself.

Atoms are some of the smallest units of matter. Each atom includes electrons orbiting around a tiny nucleus deep within its core, which contains almost all its mass and energy. Atomic nuclei are composed of two nearly identical particles: charged protons and uncharged neutrons. The number of protons in a nucleus determines which element the atom belongs to on the periodic table and thus its chemistry. Isotopes of an element have the same number of protons but a different number of neutrons.

At the NSCL, nuclei were accelerated to near the speed of light and smashed apart into fragments creating strontium-73 - a rare isotope that is not found naturally on Earth but can exist for short periods of time during violent thermonuclear X-ray bursts on the surface of neutron stars. This isotope of strontium contains 38 protons and 35 neutrons and only lives for a fraction of a second.

Working around the clock over eight days, the team created more than 400 strontium-73 nuclei and compared them to the known properties of bromine-73, an isotope that contains 35 protons and 38 neutrons. With interchanged number of protons and neutrons, bromine-73 nuclei are considered "mirror partners" to strontium-73 nuclei. Mirror symmetry in nuclei exists because of the similarities between protons and neutrons and underlies scientists' understanding of nuclear physics.

Roughly every half-hour, the researchers created one strontium-73 nucleus, transported it through the NSCL's isotope separator and then brought the nucleus to a stop at the center of a complex detector array where they could observe its behavior. By studying the radioactive decay of these nuclei, the scientists found that strontium-73 behaved entirely differently from bromine-73. The discovery raises new questions about nuclear forces, according to Rogers.

"Strontium-73 and bromine-73 should appear identical in structure, but surprisingly do not, we found. Probing symmetries that exist in nature is a very powerful tool for physicists. When symmetries break down, that tells us something's wrong in our understanding, and we need to take a closer look," Rogers said.

What the scientists saw will challenge nuclear theory, according to Daniel Hoff, a UMass Lowell research associate who was the lead author of the article published in Nature.

"Comparing strontium-73 and bromine-73 nuclei was like looking in a mirror and not recognizing yourself. Once we convinced ourselves that what we were seeing was real, we were very excited," Hoff said.

Along with Rogers, a Somerville resident, and Hoff of Medford, the UMass Lowell team included Physics Department faculty members Assistant Prof. Peter Bender, Emeritus Prof. C.J. Lister and former UMass Lowell research associate Chris Morse. Physics graduate students Emery Doucet of Mason, N.H., and Sanjanee Waniganeththi of Lowell also contributed to the project.

As part of the team's study, state-of-the-art theoretical calculations were carried out by Simin Wang, a research associate at Michigan State, and directed by Witold Nazarewicz, MSU's John A. Hannah Distinguished Professor of Physics and chief scientist at the Facility for Rare Isotope Beams (FRIB), which will open next year.

The researchers' work "offers unique insights into the structure of rare isotopes," Nazarewicz said. "But much still remains to be done. New facilities coming online, such as FRIB at MSU, will provide missing clues into a deeper understanding of the mirror symmetry puzzle. I am glad that the exotic beams delivered by our facility, unique instrumentation and theoretical calculations could contribute to this magnificent work."

Plans for more experiments are already underway, as the researchers seek to refine and confirm their observations and study these isotopes further.

CAMBRIDGE, MA -- Using a specialized magnetic resonance imaging (MRI) sensor, MIT neuroscientists have discovered how dopamine released deep within the brain influences both nearby and distant brain regions.

Dopamine plays many roles in the brain, most notably related to movement, motivation, and reinforcement of behavior. However, until now it has been difficult to study precisely how a flood of dopamine affects neural activity throughout the brain. Using their new technique, the MIT team found that dopamine appears to exert significant effects in two regions of the brain's cortex, including the motor cortex.

"There has been a lot of work on the immediate cellular consequences of dopamine release, but here what we're looking at are the consequences of what dopamine is doing on a more brain-wide level," says Alan Jasanoff, an MIT professor of biological engineering, brain and cognitive sciences, and nuclear science and engineering. Jasanoff is also an associate member of MIT's McGovern Institute for Brain Research and the senior author of the study.

The MIT team found that in addition to the motor cortex, the remote brain area most affected by dopamine is the insular cortex. This region is critical for many cognitive functions related to perception of the body's internal states, including physical and emotional states.

MIT postdoc Nan Li is the lead author of the study, which appears today in Nature.

Tracking dopamine

Like other neurotransmitters, dopamine helps neurons to communicate with each other over short distances. Dopamine holds particular interest for neuroscientists because of its role in motivation, addiction, and several neurodegenerative disorders, including Parkinson's disease. Most of the brain's dopamine is produced in the midbrain by neurons that connect to the striatum, where the dopamine is released.

For many years, Jasanoff's lab has been developing tools to study how molecular phenomena such as neurotransmitter release affect brain-wide functions. At the molecular scale, existing techniques can reveal how dopamine affects individual cells, and at the scale of the entire brain, functional magnetic resonance imaging (fMRI) can reveal how active a particular brain region is. However, it has been difficult for neuroscientists to determine how single-cell activity and brain-wide function are linked.

"There have been very few brain-wide studies of dopaminergic function or really any neurochemical function, in large part because the tools aren't there," Jasanoff says. "We're trying to fill in the gaps."

About 10 years ago, his lab developed MRI sensors that consist of magnetic proteins that can bind to dopamine. When this binding occurs, the sensors' magnetic interactions with surrounding tissue weaken, dimming the tissue's MRI signal. This allows researchers to continuously monitor dopamine levels in a specific part of the brain.

In their new study, Li and Jasanoff set out to analyze how dopamine released in the striatum of rats influences neural function both locally and in other brain regions. First, they injected their dopamine sensors into the striatum, which is located deep within the brain and plays an important role in controlling movement. Then they electrically stimulated a part of the brain called the lateral hypothalamus, which is a common experimental technique for rewarding behavior and inducing the brain to produce dopamine.

Then, the researchers used their dopamine sensor to measure dopamine levels throughout the striatum. They also performed traditional fMRI to measure neural activity in each part of the striatum. To their surprise, they found that high dopamine concentrations did not make neurons more active. However, higher dopamine levels did make the neurons remain active for a longer period of time.

"When dopamine was released, there was a longer duration of activity, suggesting a longer response to the reward," Jasanoff says. "That may have something to do with how dopamine promotes learning, which is one of its key functions."

Long-range effects

After analyzing dopamine release in the striatum, the researchers set out to determine this dopamine might affect more distant locations in the brain. To do that, they performed traditional fMRI imaging on the brain while also mapping dopamine release in the striatum. "By combining these techniques we could probe these phenomena in a way that hasn't been done before," Jasanoff says.

The regions that showed the biggest surges in activity in response to dopamine were the motor cortex and the insular cortex. If confirmed in additional studies, the findings could help researchers understand the effects of dopamine in the human brain, including its roles in addiction and learning.

"Our results could lead to biomarkers that could be seen in fMRI data, and these correlates of dopaminergic function could be useful for analyzing animal and human fMRI," Jasanoff says.

A recent study has found that late menopausal status is associated with an elevated level of depressive symptoms that indicate the negative dimension of mental well-being. However, menopause was not linked to positive dimensions of mental well-being in women aged 47 to 55. The results also suggest that a high level of physical activity was linked to fewer depressive symptoms, higher satisfaction with life and higher positive affectivity in menopausal women.

"According to our research, postmenopausal women had more depressive symptoms than peri- or premenopausal women," says doctoral student Dmitriy Bondarev from the Gerontology Research Center and Faculty of Sport and Health Sciences, University of Jyväskylä, Finland. "At the same time menopause was not related to positive mental well-being."

The menopausal transition is divided into three stages. Pre-menopause begins five to ten years before the menopause with gradual irregularity in menstrual cycles. Perimenopause is the time prior to last menstruation, when the function of the ovaries noticeably fades away. Postmenopause is the time after the last menstruation.

Menopause occurs on average between the ages of 46 and 52 and signifies the aging of a woman's reproductive system, which has a far-reaching effect on many bodily functions. However, the link between menopause and psychological functioning in middle-aged women has been investigated less.

The findings of the study indicate that irrespective of the menopausal status, physical activity was beneficial for mental well-being in middle-aged women.

"Physically active women had lower depressive symptoms, had higher positive affectivity scores and were more satisfied with life in comparison to inactive women," Bondarev explains. "Thus, being physically active during the menopausal transition may help to withstand the negative influence of menopause on depressive symptomatology and spare positive mental well-being."

The study is a part of the Estrogenic Regulation of Muscle Apoptosis (ERMA) study involving over 1,000 women aged 47 to 55 living in Jyväskylä, Finland. In the present study, the menopausal stage was determined by the serum hormone concentrations and menstrual diaries. Mental well-being and physical activity were self-reported by the participants.

The formation pressure governs the generation, expulsion, migration, accumulation and preservation of petroleum. Fluid-rock interactions during diagenesis and mineralization are also affected by the formation pressure. Thus, investigating the formation paleo-pressure in sedimentary basins is an important aspect of research into the mechanisms and processes related to hydrocarbon accumulation, and it plays an increasingly important role in hydrocarbon exploration and prospective prediction.

The formation pressure is formed during the long-term evolution of basins, and regulated by tectonism, deposition, diageneses, fluid flow, geothermal field, and magmatic activity. Oil and gas exploration is increasingly directed at deep, ultra-deep and ancient strata which, however, have generally experienced multiple stages of tectonic movements. Reconstruction of formation paleo-pressure in these strata is not easy.

Various methods have been established for paleo-pressure reconstruction in sedimentary basins, including approaches based on basin modelling, fluid inclusion analysis, differential stress of rocks, transformation of clay minerals, acoustic transit time of mudstones, and seismic wave velocity. Each of these methods has advantages and limitations, but most can only determine the formation pressure in a certain geological period, rather than the whole pressure evolution process. Furthermore, some of these methods were established based on simple porosity evolution models, which are not applicable to reservoirs with complex fluid flows, intense tectonic activities, and abnormal porosity evolution paths.

Origins of abnormal pressures typically change during geological history. In this study, a new method is proposed for reconstructing the paleo-pressures in strata by integrating various paleo-pressure calculation methods according to the identification of the formation mechanism and the main factors responsible for controlling abnormal pressures. According to the geological background, quantitative analyses of the factors that might control overpressure were first conducted to clarify the contributions of each mechanism during different geological periods. Pressure evolution was reconstructed by fluid-compaction modelling with constraints imposed by the paleo-pressures obtained from fluid inclusions or differential stress methods. Determining the mechanisms responsible for overpressures during geological history is the basic prerequisite for paleo-pressure research. Thus, quantitative studies were conducted of the contributions of disequilibrium compaction, gas charging, oil cracking, temperature reduction, and tectonic uplift and subsidence to overpressures.

Three case studies of paleo-pressure reconstruction were performed for the Sinian strata in the Sichuan Basin, Ordovician strata in the north uplift in the Tarim Basin and the Permian strata in the Sulige Gas Field in the Ordos Basin, where these three study sites are normally pressured, weakly over-pressured and abnormally low pressured at present, respectively.

The Sinian formation in the central Sichuan Basin is mainly normally pressured at present. Under the constraint of the trapping pressures due to fluid inclusions in three periods, which were calculated using PVTsim software, the evolution of pressure in the Dengying Formation was obtained by basin modelling with a fluid-compaction coupling model. Pressure in the Sinian Dengying Formation is due to a combination of hydrocarbon accumulation, oil cracking to form gas, and temperature reductions caused by tectonic uplift, where these different factors played dominant roles during diverse periods.

The Sulige Gas Field in the Ordos Basin is a typical gas field with an abnormally low pressure. A great temperature reduction from 165°C to 105°C was occurred in the last 100 Ma. Regardless of gas dissipation, pressure would be decreased by 17.7?22% when temperature declined by 50?60°C. On the other hand, gases were dissipated 17?24 vol%, resulting in 23-32% decreases in the formation pressure. Based on fluid inclusion analysis and numerical modelling, weak overpressures occurred twice throughout the geological history, where the first overpressure was generated at 195 Ma, which was suspended by the uplift at 160 Ma before, overpressure was generated again after 140 Ma, where it was maximized in 98 Ma at a greatest depth of 4425.6 m and with a pressure coefficient value of 1.1. Subsequently, both the formation pressure and pressure coefficient decreased gradually due to uplift and denudation, and changed to an abnormally low pressure with a coefficient of 0.85 at present.

The fluid pressure during the critical period of tectonic compression can be quantitatively calculated using the differential stress method with calcite twins as a paleo-barometer. The paleo- pressure in the Ordovician Yinshan carbonate strata in the Shunnan Area of the Tarim Basin was reconstructed as a case study. The Shunnan Area was in a tectonic compression environment from the middle and late Caledonian to the Hercynian period, and the orientation of the principal stress changed from SW-NE to SE-NW. The paleo-stress ranged from 66.15 to 89.17 MPa, with an average of 82.06 MPa in the Caledonian, and ranged from 56.97 to 79.29 MPa, with an average value of 66.80 MPa in the Hercynian. The excess fluid pressure in the carbonate strata during tectonic compression deformation was calculated by the difference between realistic effective vertical stress and theoretical vertical stress. Combined with modelling results, a weak overpressure was developed in the Ordovician strata during the middle to late Caledonian period by the strong compression related to the Paleo-Kunlun Ocean subduction. The formation pressure gradually deceased to normal pressure because of strata uplift and stress field conversion. Another two phases of overpressure were formed at the end of the Permian and Neogene periods, originated from southeast-trending compression and gas filling, respectively.

Pressure analysis is the basis of fluid dynamic system analysis, which is significant for hydrocarbon migration and reservoir diagenesis. The development of effective paleo-pressure recovery methods for carbonate strata may be essential for addressing various problems in deep and ultra-deep layer pressure research.

Across the world, animals are kept in captivity for various reasons: in zoos for education and research, in research facilities for testing, on farms for meat and other products, and in people's homes as pets. Maintaining good animal welfare is not only important for ethical reasons; poor welfare can impact human wellbeing and the economy. But how do we assess how animals are feeling?

One way to assess animal wellbeing is to look at stress levels. Vets typically use two biological measures of stress: stress hormone levels and white blood cell ratios. In mammals - including humans - the most important stress hormone is cortisol. When animals are faced with danger, cortisol is produced to help prepare the body for a challenge. However, if high stress and cortisol are experienced constantly, they can impact an animal's health.

In addition to cortisol, scientists can also look at the ratio of two types of white blood cells, heterophils (or neutrophils) and lymphocytes. These cells play an important role in the immune system of mammals, and after animals have experienced a stressful event, their ratio is typically high.

Researchers at the University of Turku, Finland, wanted to find out if these two biological measures of stress were correlated and whether animals with high levels of cortisol also had a high heterophil to lymphocyte ratio. They measured cortisol and heterophil to lymphocyte ratios in 120 Asian elephants from a semi-captive population of working timber elephants in Myanmar. The researchers also weighed each elephant, as body weight is a good indicator of general health.

"Some previous studies have found a positive relationship between stress hormones and heterophil to lymphocyte ratios, while others have found no relationship at all. It was also unclear from previous studies whether these two measures of stress are comparable across individuals of different sex and age, as well as across the seasons. In this population, we found that elephants with higher levels of the stress hormone cortisol also had higher ratios of heterophils to lymphocytes. This was true regardless of sex and age," says Postdoctoral Researcher and the lead author on the first study, Martin Seltmann, from the Department of Biology at the University of Turku.

An additional aim of the study was to test if stress hormones and heterophil to lymphocyte ratios are related to body weight in Asian elephants.

"We did not find a link between the white blood cell ratios and body weight, but elephants with higher levels of stress hormone had a lower body weight, indicating that elevated stress is linked to weight loss. It is useful to see that both a biological marker (cortisol) and physical indicator (body weight) of welfare respond in the same way. This means that both markers can be used to assess the wellbeing of elephants," says researcher Susanna Ukonaho, who participated in the study.

Non-experts Can Identify Stress Behaviour

In the second study, the researchers investigated whether welfare can also be reliably assessed by observing an animal's behaviour. While elephant specialists may be able to quickly identify behavioural changes, expert knowledge is not always available, so the researchers wanted to test the reliability of behavioural assessments by non-experts. First, they filmed over 100 working Asian elephants undertaking tasks that were either familiar or new to them.

"The elephants were asked to pick up different types of objects, including objects they had never seen before. This included items such as a plastic bottle, which some elephants were clearly unsure about," says the lead author on the study, Jonathan Webb.

The researchers constructed a list of elephant behaviours, which was then used by three volunteers with no prior experience of Asian elephants to collect behavioural data from the films.

To assess the reliability of the behavioural data, the researchers looked at how similar the observers' scores were for each film. They also assessed observer consistency by getting the volunteers to score films twice. They found that all three volunteers consistently and reliably identified many elephant behaviours, indicating that even with limited experience, people can reliably monitor elephant behaviour in a way which could improve the quality and safety of working elephant-human relationships.

Behavioural markers could therefore be a simple but useful tool for elephant welfare assessment on a larger scale, although the researchers caution that we still need to know how different behaviours are linked to biological measures of stress.

The relationship between different measures of animal welfare is often complex, but the findings of these two studies show that, at least when working with elephants, caretakers have several options for assessing the wellbeing of their animals. These options will not only facilitate the caretakers' work, but also help elephants to live better and healthier lives.

ROCHESTER, Minn. -- Surgery performed on a fetus in the womb to repair defects from spina bifida triggers the body's ability to restore normal brain structure, Mayo Clinic research discovered.

Research by Rodrigo Ruano, M.D., Ph.D., chair of Mayo Clinic's Division of Maternal and Fetal Medicine, finds that fetal surgery to correct congenital spinal cord defects is more effective at healing neurological structure than surgery after birth. This research was published in Mayo Clinic Proceedings.

"We discovered the main benefit of this procedure is not only to close the spine, but the most important thing is to improve the brain structure and the brain anatomy," says Dr. Ruano. "Our study shows we can regenerate the brain structure so that it comes back to better development."

Dr. Ruano's research focused on three last consecutive patients with myelomeningocele who underwent fetal surgery, the most common and serious form of spina bifida. Myelomeningocele is a condition in which the backbone and spinal canal do not close properly. Membranes and spinal nerves push through this opening, forming a sac and exposing tissues and nerves. This makes the baby prone to life-threatening infections.

In each case, a related neurological disorder, known as Chiari malformation, or hindbrain herniation, pushed the brain down through the base of the skull. That may lead to a buildup of fluid on the brain, causing a condition known as hydrocephalus. Oftentimes, infants with hydrocephalus require a shunt after birth to drain the fluid from the brain.

"Our hypothesis is if we closed the spinal defect in utero, we could prevent inflammation and trauma to the nerves, and most importantly stop the leakage of brain fluid through the base of the skull. And the posterior part of the brain can be restored or improved," says Dr. Ruano. "The study showed that after in utero intervention, the brain healed itself and prevented a more severe buildup of fluid on the brain."

Dr. Ruano and his team performed surgery on each of the babies to close the spinal cord opening between 23 and 26 weeks of gestation. MRI scans performed six weeks later while the babies were still in the womb showed the brain structure had been restored in each baby before birth.

The babies were delivered at 37 weeks via cesarean section with no complications. None of the babies needed a shunt to drain fluid from the brain after birth, and each baby was discharged from the hospital within three days.

Approximately 1 in every 4,000 babies, or 1,645 infants every year, are born in the United States with myelomeningocele, according to the Centers for Disease Control and Prevention. Left untreated, this type of spina bifida and Chiari malformation can lead to serious disabilities. Each case is different, but disabilities can range from bowel and bladder disorders to mobility problems and paralysis.

Future studies will be needed to investigate the benefits of open, in utero surgery, which requires a larger incision in the uterus versus fetoscopic surgery that is performed through two small incisions.

Two studies of the coronavirus COVID-19 outbreak recently published in the open-access journal PLOS ONE.

The first study, published March 31, 2020, was conducted by Constantinos Siettos from the Universita degli Studi di Napoli Federico II, Italy and colleagues. The authors used a Susceptible-Infected-Recovered-Dead (SIRD) model calibrated with the reported data between January 11 and February 10, 2020 and forecasted the evolution of the outbreak in the epicenter of the outbreak, Hubei, China up until February 29. With these parameters, they forecasted that at least 45,000 would be infected and 2,700 would die by February 29 - in fact, in Hubei, around 67,000 are known to have become infected, while the death toll was around 2800 in this time period.

The authors also used the SIRD model to estimate COVID-19's R0 value, an estimate of contagiousness which reflects the average number of people who may catch an infection from one contagious person. Across various scenarios, their estimate of R0 based on the available data was around 2.5. Assuming a high degree of underreporting of mild cases of COVID-19 in their data, they estimated a mortality rate in the total population of around 0.15% for the virus. Furthermore, based on a scenario assuming an order of 20-fold scaling of the number of infected in the total population, their study predicted a decline of the outbreak at the end of February in Hubei. Indeed, during the last days the number of new infected cases has dropped significantly.

Dr Siettos notes: "This is the first study based on a mathematical modelling approach that has provided relatively accurate three- week-ahead forecasts. Importantly, to the best of our knowledge this is the first study based on a mathematical modelling approach suggesting that the actual number of the infections in the total population is of the order of twenty times more than those reported, and that the mortality rate in the total population is about ~0.15% i.e. significantly less than reported 2-3%.Our findings imply that for the case of Hubei (with a 60m population), around 2%-3% of the total population in Hubei has been actually infected by coronavirus."

The second study, published March 19, 2020, was conducted by Mingli Yuan and colleagues from the Central Hospital of Wuhan, Hubei province, China. The researchers studied 27 patients infected with COVID-19 and admitted to the Central Hospital of Wuhan.

In this patient group, the authors associated clinical features identified from computed tomography (CT) scans of patients' lungs with eventual outcomes. They scored patients based on features they observed such as ground glass opacity, abnormality on both sides, and widespread distribution of pathology in the lungs, to produce an overall severity score for each patient.

Of the 27 patients, who were mostly older adults (median age 60), 17 (63 percent) recovered and were discharged from hospital, while 10 (37 percent) died of the virus. Patients with underlying health conditions including hypertension, diabetes and cardiac disease were more likely to die of the virus than patients without such comorbidities, and older patients were also more likely to die, though there was no difference between genders. Patients with a higher (more severe) score at CT scan were much more likely to die of COVID-19 - the average score of patients who died was 30, compared to 12 in patients who recovered.

Dr Yuan adds: "This study allows us to compare radiologic findings with the mortality of patients infected with COVID-19."

Investigators at St. Jude Children's Research Hospital have found that the ABCC4 transporter is critical to the SHH signaling pathway in the brain tumor medulloblastoma. This work provides a rationale for development of small molecule inhibitors that target ABCC4. The findings appeared in Cancer Research.

Medulloblastoma is the most common malignant pediatric brain tumor. There are four genomic subgroups of the disease: WNT, SHH, Group 3 and Group 4. The SHH subgroup accounts for about 25% of all pediatric medulloblastoma cases. The five-year survival rate for SHH medulloblastoma is approximately 75%.

Transporters are proteins found on the cell membrane. They help substances enter and exit cells. The researchers found that the ABCC4 transporter is highly expressed in SHH medulloblastoma.

"We have studied the ABCC4 transporter for many years, and wanted to better understand how it interacts with critical pathways that drive tumor growth, like SHH," said senior author John Schuetz, Ph.D., of the St. Jude Department of Pharmaceutical Sciences. "By teasing apart the relationship between ABCC4 and the SHH pathway, we've identified a novel strategy for potentially treating these tumors."

The researchers built a medulloblastoma "interactome" to determine which proteins interact with and are essential to the SHH pathway. The findings showed that ABCC4 is highly expressed in the SHH subgroup and is required for optimal activation of the pathway.

The researchers found that increased expression of ABCC4 correlates with poor overall survival in SHH medulloblastoma. Targeting ABCC4 using genomic methods reduced the size of medulloblastoma tumors and extended the lifespan of mouse models.

"By following the web of interactions between different parts of key tumor pathways, we can take a more targeted approach to cancer therapy," said first author Juwina Wijaya, Ph.D., formerly a postdoctoral fellow in Schuetz's laboratory. "We now know another one of SHH medulloblastoma's weaknesses."

Infants who were started on solid foods at or before three months of age showed changes in the levels of gut bacteria and bacterial byproducts, called short-chain fatty acids, measured in their stool samples, according to a study from researchers at Johns Hopkins Bloomberg School of Public Health.

Prior studies have linked the early introduction of solid foods to a higher chance of being overweight in childhood. The new study, published in BMC Microbiology, suggests that early solid food introduction may predispose infants to being overweight at least in part by altering the gut bacterial population.

"How the early introduction of solid foods would cause the later development of obesity has been unknown, but our findings suggest that disruptions to gut bacteria may be one explanation," says Noel Mueller, PhD, assistant professor in the Department of Epidemiology at the Bloomberg School.

Pediatricians' associations typically recommend that infants be breastfed exclusively for the first four to six months, after which solid foods should be introduced as a supplement to breastmilk or milk formula. Past research suggests that children who start eating solid foods earlier than six months are more likely to be overweight in childhood. Prior studies also indicate that the timing of solid food introduction may affect the chances of developing eczema, food allergies, asthma, hay fever, and other allergy-related conditions.

To understand better how the timing of solid food introduction, in terms of biological mechanisms, could affect a child's metabolic and/or immune health, Mueller and his colleagues analyzed data from the Nurture study, which tracked infants in a community in Durham, North Carolina, for the first year of life and was set up principally to explore early-life factors that might predispose to obesity.

The scientists conducting the study interviewed the mothers every three months about the infants' diets and other factors and also collected stool samples from the infants. Data from 67 children were included in the new analysis, for which the researchers compared the timing of solid food introduction with the bacterial species and byproducts found in the month-3 and month-12 stool samples.

The team found that the samples from infants who had started on solid foods at or before three months, at the month-3 time point and even at the month-12 time point, contained a significantly higher diversity of bacteria, indicating a more diverse gut bacterial population or "microbiome," compared to samples from infants who had started later on solid foods. This finding is consistent with a 2018 Norwegian-led study, which linked higher gut microbiome diversity at 3 months of age to a greater chance of being overweight later in childhood.

The researchers also measured the stool-sample levels of organic bacterial byproducts called short-chain fatty acids. Prior studies have linked higher stool levels of butyric acid and other short-chain fatty acids in adults to increased risks of obesity, diabetes, and hypertension. Mueller and colleagues found in their study that infants starting on solid foods by three months had significantly higher concentrations of butyric acid, as well as total short-chain fatty acids, at 12 months--but not at 3 months, which could indicate a delayed and sustained impact of early solid-food introduction.

Mueller concludes that, on the whole, the findings are consistent with the emerging evidence that gut microbiome changes are key factors in the development of common metabolic and immune conditions, and suggest that scientists are on the right track in studying these changes. And, the authors say that further research is needed to determine if these measures of microbiome diversity and short-chain fatty acid concentration truly drive the development of obesity and other disorders.

Mueller and colleagues are continuing to conduct studies of diet and the gut microbiome in infants and children, and the associations between these factors and outcomes such as obesity and immune-related disorders.

"Timing of complementary feeding is associated with gut microbiota diversity and composition and short chain fatty acid concentrations over the first year of life" was written by Moira Differding, Sara Benjamin-Neelon, Cathrine Hoyo, Truls Østbye, and Noel Mueller.