Earth

In the world of materials science, many have heard of crystals, highly ordered structures in which atoms are arranged in a tight and periodic manner (in which the atomic arrangement is repeated). But, not many people know about quasicrystals, which are unique structures with strange atomic arrangement. Like crystals, quasicrystals are also tightly arranged, but what's different about them is the fact that they possess an unprecedented pentagonal symmetry, such that the atomic arrangement is highly ordered but not periodic. This distinctive feature gives them unique properties, like high stability, resistance to heat, and low friction. Since their discovery only about 30 years ago, scientists globally have been trying to understand the properties of quasicrystals, in an effort to make more advancements in materials research. But, this is not easy, as quasicrystals are not prevalent in nature. Luckily, they have been able to make use of structures similar to quasicrystals, called "Tsai-type approximants." Understanding these structures in detail could give insights into the many properties of quasicrystals. One such property is antiferromagnetism, in which magnetic moments are aligned in a quasiperiodic order, strikingly distinguished from conventional antiferromagnets. This property has never been observed in quasicrystals so far, but the possibility was exciting for materials scientists, as it could be a gateway to a plethora of new applications.

In a new study published in Physical Review B: Rapid Communications, a team of scientists at Tokyo University of Science, led by Prof Ryuji Tamura, found for the first time that a type of Tsai-type approximant exhibits an antiferromagnetic transition. This was an exciting finding, as it suggested that even quasicrystals could show such a transition. The scientists already knew that Tsai-type approximants have two different variants: 1/1 and 2/1 approximants. The main difference between the two is that 2/1 approximants contain an additional rhombohedral unit in their structure, which is absent in the 1/1 type, making them even more highly ordered and closer to the structure of quasicrystals. And, this is why the scientists wanted to see the conditions in which 2/1 approximants could show antiferromagnetism; it created a possibility of seeing this new property even in quasicrystals. Prof Tamura says, "Antiferromagnetic transitions have been observed in 1/1 approximants, but we observed it in a 2/1 approximant for the first time. This is interesting because unlike the 1/1 approximant, the 2/1 approximant contains all the components necessary to construct a quasicrystal."

To take a closer look at the magnetic properties of 2/1 approximants, the scientists synthesized metallic alloys with a crystalline structure, which contained both 1/1 and 2/1 approximants. By using a device called the superconducting quantum interference device (SQUID), they studied the conditions under which the approximants showed different magnetic properties. Interestingly, they found that a single parameter dictates the presence of antiferromagnetism in both types of approximants. This was the ratio of electron per atom, which slightly differed in the two types. By manipulating the electron-per-atom ratio, Prof Tamura and his team saw a "transition" to an antiferromagnetic state in both types of approximants. This property had been seen in the 1/1 type before but never in the 2/1 approximant. This was an exciting development, as the highly ordered structure of the 2/1 approximant meant that it could be used to generate quasicrystals, making this the very first study to show the possibility of antiferromagnetic quasicrystals. Elaborating on their findings, Prof Tamura says, "We succeeded in observing, for the first time, antiferromagnetic transitions in the 1/1 and 2/1 AFM approximants in the same alloy system." He adds, "Our finding clearly shows that the antiferromagnetic order survives in the 2/1 higher-order approximant, which has all the building blocks for creating a quasicrystal."

The significance of quasicrystals--such as in routine applications like making frying pans and needles for acupuncture and surgery--is well known. But, given their very recent discovery, not much has been understood about what makes them so unique. By showing the existence of antiferromagnetism in a quasicrystal-like structure, Prof Tamura and his team have potentially paved the way for greater developments in quasicrystal research. Prof Tamura concludes by saying, "Antiferromagnetic quasicrystals had never been seen before, and this discovery has a great academic impact." He adds, "The possibility of the existence of antiferromagnetic quasicrystals is a big step towards deciphering the mystery of quasicrystals."

When our skin is damaged, a whole set of biological processes springs into action to heal the wound. Now, researchers from the VIB-UGent Center for Inflammation Research have shown that one of the molecules involved in this, HMGB1, slows down wound healing. It is, however, also essential for tumor formation at sites of previous injury. The researchers found that HMGB1 controls the actions of neutrophils, a specific type of immune cells, in skin wounds and that this is crucial for cancer initiation. Targeting this pathway could be beneficial in diabetic wound care and in patients suffering from skin blistering diseases. Their work appears in Cell Reports.

NETting wounds

Wounding initiates a complex repair mechanism that is aimed at fast regeneration of the injured tissue. A large amount of clinical data shows that chronic inflammation or previous injury can predispose tissues to tumor formation, a hypothesis already stated in the nineteenth century.

However, it is still not fully understood what the molecular mechanisms are that link injury repair to cancer. The first immune cells that enter the skin after injury are neutrophils, short-lived immune cells that form specialized structures termed NETs (neutrophil extracellular traps) in skin wounds.

Skin wounds and cancer risk

Dr. Esther Hoste, first author of the study, and colleagues in the group of prof. Geert van Loo (VIB-UGent Center for Inflammation Research) investigated the role of the molecule HMGB1 in injury repair and tumor initiation in the skin. HMGB1 is a molecule that is secreted by damaged tissue and activates the immune system. The scientists genetically deleted HMGB1 from skin cells in mice and showed that their wounds healed faster than normal mice and that they are completely protected from wound-induced tumor formation.

Mice lacking HMGB1 from epithelial skin cells showed reduced neutrophil numbers and NETs in skin wounds. Dr. Hoste explains: "We demonstrated that a mechanism used to alarm your immune system that something is going wrong, can be hijacked for cancer initiation. While secretion of HMGB1 is a good thing in conditions of minor injury, it can be a harmful event in more serious or chronic wounds as it can trigger tumor formation at these wound sites. This really is a case of 'too much of a good thing can hurt you.'"

The harmful NETs that link wound repair to tumor formation were also observed in patients suffering from the severe blistering disease Recessive Dystrophic Epidermolysis Bullosa. These patients undergo repetitive cycles of injury and repair and are at high risk to develop skin cancer.

Faster healing, without cancer

The findings strongly suggest that targeting HMGB1 release or NET formation in the skin might be of interest in blistering diseases or in diabetic patients suffering from chronic ulcers. Such HMGB1-focused therapies could accelerate wound healing responses, while limiting the risk of cancer initiation.

"We were surprised that interfering with the secretion of one molecule provided such benefits to the injury repair process and could completely block tumor formation. We now want to investigate whether this newly identified molecular pathway also affects other tissues where trauma is linked to tumor formation, such as the intestine. We are currently working on new ways to inhibit this detrimental pathway in order to bring our findings to the clinic," says prof. Geert van Loo.

Fens and bogs are valuable research environments for paleoecologists due to ancient fossils that have survived in the peatland for thousands of years. A recent study carried out by the paleoecologists of Tallinn University of Technology reveals that the rich biodiversity of spring fens is a result of their millenniums-long stable environment. The continuously high local richness in spring fens is contrary to the general decrease in biodiversity around the world caused by increasingly intensive land use.

The study of bogs and fens carried by Estonian scientists is particularly valuable because in most parts of Europe they have been destroyed due to rapid industrialization and agricultural development. The research group led by Triin Reitalu and PhD student Ansis Blaus from the Division of Quaternary Geology of TalTech Department of Geology studied one of the oldest fens in Estonia, the Kanna spring fen in Viidumäe nature reserve in Saaremaa. Spring fens cover only 0.02% of the area of Estonia, but their vegetation is unique - several orchids, Saaremaa yellow rattle, bird's-eye primrose and a number of other rare plant species grow in spring fens. Approximately 60% of the area of spring fens is protected under the Nature Conservation Act.

"Spring fens are a rare type of wetlands, where water flows constantly due to pressurised groundwater inflow. The Kanna spring fen is located at the foot of the Saaremaa upland and the water flowing down the slopes of calcareous moraine makes the fen environment unique," Triin Reitalu says. Such calcareous soils create good conditions for diversity of vegetation.

"In our study, we travel 9,200 years back in time - to the time when the current fen emerged from the sea in the Baltic basin and, for the first 2,000 years, developed as a small bog between dunes. Peat mosses, heather, ledum and gale grew there. From then on, about 7,000 years ago, the bog developed into a spring fen due to water flow," Reitalu explains. During that period, the climate had become not only warmer but also dryer after the last Ice Age, which in turn led to increased role of mineral-rich surface water that started to flow from the slopes.

The scientists used peat core analysis as a research method. For this, a 2.3 m long peat core was obtained from the fen and was analysed at a laboratory. The peat soils of spring fens develop very slowly, so this 2.3 meters long drilled core covers the natural history of the past 9,200 years.

Plant micro- and macrofossils analyses were carried out in the study.

The microfossils studied included pollen and spores. Although pollen is light and capable of flying long distances, it resists thousands of years because of its strong husks and is therefore good material for research.

The macrofossils studied included various plant remains, seeds, bark pieces, etc. Macrofossils are less mobile than microfossils, but they give a picture of the plant community that grew locally in fen through the past.

The analyses indicate that vegetation diversity was the highest in Kanna spring fen and the surrounding area in the period from ca 7,500 to 400 cal BP. The last ca 400 years are, however, characterized by the decline of the number of broad-leaved tree species around the fen (limes, elms, hornbeams disappeared). Despite of some vegetation changes, the fen environment in Kanna has been relatively stable for the last 7,000 years.

Triin Reitalu says, "Due to their specific biota, spring fens have been in the focus of nature conservation for more than half a century. Our current research provides a unique picture of the development of spring fens over the last millennia. We can conclude that the present high diversity of the fen is a result of a long-term stable environment."

"I would regard conservation of biodiversity an insurance policy for the survival of mankind," Reitalu says. Take for example the trend of natural pollinators toward extinction: as is well known, the fruit trees in our gardens need pollinators (honeybees and bumble bees) for fructification. In the current era of monocultures, however, the bees are declining in abundance and the yield of fruit trees is therefore at risk. Preservation of a diverse range of natural and semi-natural communities in a landscape is the best way to ensure e.g. high yield from apple trees in our home gardens.

CHARLOTTESVILLE, VA (NOVEMBER 26, 2019). Researchers from the University of Michigan found significant pupillary changes in high-school football athletes after they had sustained a high-acceleration head impact. The changes were detected using a noninvasive, hand-held, quantitative pupillometry device, which potentially could be used in a nonclinical setting for a quick assessment of possible brain injury. Detailed findings on this subject are found in the article, "Pupillary changes after clinically asymptomatic high-acceleration head impacts in high school football athletes," by Jacob R. Joseph, M.D., and colleagues, published today in the Journal of Neurosurgery.

Background

During American football practices and games, athletes are regularly subjected to head impacts of varying intensities--hits that may or may not produce the clinical signs and symptoms of a concussion.

Previous studies have found associations between high-acceleration head impacts and neuronal and axonal injury, even in the absence of symptoms and diagnosis of concussion. These studies have relied on the results of invasive tests, such as biomarker analysis and advanced neuroimaging, which are expensive, time-consuming, and not always readily available.

The authors of this study looked at the potential of quantitative pupillometry (QP) as an objective, fast, and noninvasive method to assess the neurological effects of high-acceleration head impacts when no symptoms are apparent. QP provides objective, quantifiable data on changes in pupil size and reactivity to light. Such changes can reflect changes in brain function.

Present Study

Thirteen high-school football players completed the entire study. Sensors were placed in these athletes' football helmets to measure and record the frequency and intensity of head impacts during all practices and games in a football season. Data on all head impacts were collected for each athlete. The focus of this study was on high-acceleration head impact, which was defined as an impact that simultaneously exceeds 95-gravity linear acceleration and 3760-radian/second2 rotational acceleration.

QP was performed to measure each athlete's pupil size and reactivity to light (in all, eight parameters of the pupil) at various time points throughout the playing season and to compare these measurements with normative data. The authors state that testing only took two minutes per session, and in each instance the ambient lighting was similar. Testing was performed 1) before the playing season began; 2) at the middle of the season, following a game; 3) after the season had ended; and 4) in athletes who sustained a high-acceleration head impact, following the practice session or game in which the impact occurred.

At the time of pupillometry testing, the athletes also underwent neurocognitive testing to determine whether the impacts produced concussive injuries. This was performed using the Sport Concussion Assessment Tool, 5th Edition. The authors focused on evaluations of symptoms, cognitive screening, balance assessment, and delayed recall.

Seven athletes experienced high-acceleration head impacts without a related concussion diagnosis during the playing season, six of them before the midseason evaluation. In a comparison of QP measurements obtained following high-acceleration head impacts with those obtained at the midseason evaluation (control), the authors found significant decreases in three of the eight QP parameters, specifically pupil dilation velocity, percent change in pupil diameter, and maximum pupil constriction velocity.

In a comparison of QP measurements across the playing season (measurements obtained at the preseason [baseline], midseason, and end-of-season evaluations), the authors found significant changes in two QP parameters, namely average pupil constriction velocity and maximum pupil constriction velocity.

The authors found no significant changes in neurocognitive test values when they compared values obtained following a high-acceleration head impact with values obtained at the midseason evaluation. They also found no significant changes when they compared neurocognitive test values across the playing season.

The results of this study show that measurable changes in pupillary parameters occurred following asymptomatic (non-concussion-related) high-acceleration head impacts. The authors state these results suggest that "nonconcussive [high-acceleration head impacts] may affect intrinsic brain reflex pathways and may reflect biological injuries that previously were found using more invasive methods" such as biomarker analysis and advanced neuroimaging.

QP may prove to be an inexpensive, rapid, objective, noninvasive method of determining brain injury following sports-related head impacts.

The authors point out that the sample of athletes evaluated in this study is small and the study is preliminary. The authors stress the importance of conducting a larger study to confirm their findings.

When asked about the study, Dr. Joseph said, "In this study, we found more evidence that extremely severe head impacts seem to have an effect on these high school athletes. We had previously found that these severe hits (high-acceleration head impacts) caused increases in traumatic brain injury biomarkers, and now we are seeing changes in the pupil's response to light, all despite the athlete being completely asymptomatic otherwise. This suggests that high-acceleration
head impacts may be the most important aspect of football and other contact sports to reduce in frequency and eventually eliminate from the game."

Eating a low-calorie diet can help you live longer and prevent age-related diseases - and even improve the immune system's function. A new study finds that, in mice, a compound used in herbal medicine can give a similar immune boost if given before vaccination - no dieting required.

In a new paper in Science Signaling, researchers at the University of Hyderabad in India and the Cornell University College of Veterinary Medicine show that a plant-based compound called halofuginone improves the immune response to a potential vaccine against dengue virus. Halofuginone tricks the body into thinking it is starving for amino acids, which activates a pathway that results in more, and better, antibodies that are better at neutralizing the virus.

The compound could ultimately be part of a strategy to improve the effectiveness of vaccines for diseases such as dengue, which have been difficult to control.

The research group was led by Avery August, Cornell vice provost for academic affairs, professor of immunology and a Howard Hughes Medical Institute professor. Collaborators included Weishan Huang, adjunct assistant research professor of microbiology and immunology; Nooruddin Khan, assistant professor of biotechnology at the University of Hyderabad in India; and doctoral students Sabrina Solouki and Jessica Elmore, both of the August lab.

From previous studies, the team knew that halofuginone activates a pathway called the amino acid starvation response, which normally kicks in when the body is starved of proteins. Restricting calories can have multiple impacts on the immune system, and the researchers wanted to know how artificially activating this pathway would affect immune response to a vaccine.

Halofuginone is a component of an herb used in Chinese medicine. It shows potential for treating muscular dystrophy, autoimmune disease and certain cancers, and appears to have few side effects. It mimics amino acid starvation in the body by blocking the enzyme that links amino acids to the molecules that deliver them to the site of protein production.

The World Health Organization lists dengue among its top 10 threats to global health, and about half the world's population is at risk of contracting the virus. It is transmitted by mosquitoes and causes flu-like symptoms in most people, but in about 20% of cases, the infection progresses into severe dengue, which can cause shock, hemorrhaging and death.

The virus has been especially difficult to control, in part because there is no vaccine suitable for individuals who have not already been exposed.

In the current study, researchers injected some mice with halofuginone and some with an innocuous salt solution, then inoculated all of the mice with a potential dengue vaccine. Then they looked for differences in the immune response to the vaccine in the two groups.

Mice that received halofuginone produced twice as many antibodies against the virus compared with mice that only received the vaccine, and these antibodies bind to dengue viral components more strongly. Mice don't contract dengue, so the researchers couldn't test whether they were protected. But when they tested the efficacy of the antibodies against dengue virus in a test tube, they saw that halofuginone resulted in antibodies that more effectively neutralized the virus.

"We were particularly surprised by the quality of the antibody response, which is the important part," August said. "In this case the actual affinity of the antibodies for the virus particles was enhanced by the halofuginone."

Furthermore, the researchers showed that halofuginone works specifically by encouraging the formation of germinal centers in the lymph nodes and spleen. Germinal centers act like factories to produce the B cells that pump out antibodies, and memory B cells that persist for decades and restart antibody production if the invader returns.

"This pathway hasn't before been thought of as one that can regulate enhancing vaccine memory," said August. "It allows us potentially to enhance the body's memory specifically for that vaccine."

Halofuginone worked equally well to enhance the immune response against the four types of dengue virus, but this approach likely would boost any vaccine.

This study primarily focused on B cells that produce antibodies against invading pathogens, but now August's group and their collaborators are examining the specific effects of halofuginone on the response of T cells, which detect the presence of invaders, kill infected cells and signal B cells to create antibodies.

Overall, the findings suggest that investigating drugs that mimic starvation may be a promising area of research for finding strategies to enhance vaccine effectiveness, especially for dengue and other diseases that still lack approved vaccines.

A literature review out of Oklahoma State University focused on notable woody plants that can disrupt biodiversity by behaving as a weed or an invasive plant.

Michael Schnelle to illuminates species important to the ornamentals industry and its consumers that, through natural geographical expansion, sheer aggressive growth in native locations, or anthropogenic activity, can sometimes be challenging to keep in-bounds, both in cultivation and in their natural geographic ranges.

The results of this review are in the article "Native Woody Plants of the Southern United States with Weedy or Invasive Tendencies: A Review of Common Offenders" published open access in the October print issue of HortTechnology.

Schnelle states of his literature review, "I wrote this manuscript to encourage people to not stereotype native or non-native plants, but rather to suggest that people should consider a species for its individual merits and shortcomings, regardless of its geographic origin."

As his article verifies, a weed is normally defined as a plant, native or non-native, that is not valued where it is growing. An invasive species is generally defined as a species that not only spreads geographically outside its typical range but also has a proclivity for displacing native flora and fauna.

Often when a native species is deemed invasive, the invasion is associated with a horticultural disturbance. However, changes in climatic conditions that have transpired over recent decades have resulted in altered population dynamics of native species and, thus, their geographic ranges.

Five woody species--black locust, yaupon holly, black cherry, snailvine, and southern waxmyrtle--are all native to Oklahoma and nearby states. They all have varying levels of use in and importance to the United States nursery industry.

These native plants have migrated to, and have become increasingly dominant, in other regions of the United States because of prolific fruit loads dispersed by birds and mammals, anthropogenic disturbances, overgrazing pastures, and certain species' tolerance of environmental extremes.

Few native species are aggressive enough to warrant production and sales bans in the southern United States, however they should be monitored.

Schnelle advises that conservationists and land managers should organize priorities based on whether species are producing benefits or harm to biodiversity, human health, ecological services, and economies.

Potential control measures include, but are not limited to, chemical applications, timely cultivation, heightened awareness of grazing practices, and prescribed burning.

The onus is on scientists, growers, and consumers to keep a watchful eye on land stewardship and other factors that could influence a species' performance relative to other plants in the same biological community. The native species, like introduced plants, should be judged on a case-by-case basis.

Schnelle suggests that plant selection for a landscape should be predicated on environmental benefits, aesthetic value, and long-term maintenance considerations, including the potential for unwanted spread regardless of the origin of the species.

Schnelle adds, "I do hope the public will find the time to read the article in its entirety to gain a better grasp of the complexity and potential for environmental degradation when native-born plant species go rogue. The first step toward solving a daunting problem of this nature is to fully understand its scope."

CHICAGO - Researchers using MRI have found signs of damage that may be related to inflammation in the brains of obese adolescents, according to a study being presented next week at the annual meeting of the Radiological Society of North America (RSNA).

Obesity in young people has become a significant public health problem. In the U.S., the percentage of children and adolescents affected by obesity has more than tripled since the 1970s, according to the Centers for Disease Control and Prevention. Data from the World Health Organization indicates that the number of overweight or obese infants and young children ages five years or younger increased from 32 million globally in 1990 to 41 million in 2016.

While obesity is primarily associated with weight gain, recent evidence suggests that the disease triggers inflammation in the nervous system that could damage important regions of the brain. Developments in MRI like diffusion tensor imaging (DTI), a technique that tracks the diffusion of water along the brain's signal-carrying white matter tracts, have enabled researchers to study this damage directly.

For the new study, researchers compared DTI results in 59 obese adolescents and 61 healthy adolescents, ages 12 to 16 years. From DTI, the researchers derived a measure called fractional anisotropy (FA), which correlates with the condition of the brain's white matter. A reduction in FA is indicative of increasing damage in the white matter.

The results showed a reduction of FA values in the obese adolescents in regions located in the corpus callosum, a bundle of nerve fibers that connects the left and right hemispheres of the brain. Decrease of FA was also found in the middle orbitofrontal gyrus, a brain region related to emotional control and the reward circuit. None of the brain regions in obese patients had increased FA.

"Brain changes found in obese adolescents related to important regions responsible for control of appetite, emotions and cognitive functions," said study co-author Pamela Bertolazzi, a biomedical scientist and Ph.D. student from the University of São Paulo in Brazil.

This pattern of damage correlated with some inflammatory markers like leptin, a hormone made by fat cells that helps regulate energy levels and fat stores. In some obese people, the brain does not respond to leptin, causing them to keep eating despite adequate or excessive fat stores. This condition, known as leptin resistance, makes the fat cells produce even more leptin.

Worsening condition of the white matter was also associated with levels of insulin, a hormone produced in the pancreas that helps regulate blood sugar levels. Obese people often suffer from insulin resistance, a state in which the body is resistant to the effects of the hormone.

"Our maps showed a positive correlation between brain changes and hormones such as leptin and insulin," Dr. Bertolazzi said. "Furthermore, we found a positive association with inflammatory markers, which leads us to believe in a process of neuroinflammation besides insulin and leptin resistance."

Dr. Bertolazzi noted that additional studies are needed to determine if this inflammation in young people with obesity is a consequence of the structural changes in the brain.

"In the future, we would like to repeat brain MRI in these adolescents after multi-professional treatment for weight loss to assess if the brain changes are reversible or not," she added.

CHICAGO - Connectivity in an area of the brain that regulates emotion may be altered in infants exposed to opioids while in utero, according to a new study being presented next week at the annual meeting of the Radiological Society of North America (RSNA).

Opioid use in pregnancy has become a major public health crisis. Opioids can have a devastating effect on maternal, fetal and infant health. When babies who have been exposed to opioids in utero are born, they suffer from drug withdrawal, or a group of conditions known as neonatal abstinence syndrome (NAS). Exposure to opioids in utero is believed to have lasting consequences on brain development and behavior.

According to the researchers, NAS requires prolonged hospital stays, monitoring and, in severe cases, additional treatment with opioids. Understanding how opioids affect the developing brain would be one of the important steps in early identification and management of NAS and in improving neurodevelopmental and behavioral outcomes in these children.

"Little is known about brain changes and their relationship to long-term neurological outcomes in infants who are exposed to opioids in utero," said Rupa Radhakrishnan, M.D., assistant professor of radiology and imaging sciences at Indiana University School of Medicine in Indianapolis. "Many studies have looked at the impact of long-term opioid use on the adult and adolescent brain, but it is not clear whether social and environmental factors may have influenced those outcomes. By studying infants' brain activity soon after birth, we are in a better position to understand the effect of opioids on the developing brain, and explain how this exposure could influence long-term outcomes in the context of other social and environmental factors."

A team of obstetricians, neonatologists, psychologists and imaging scientists collaborated to study the brains of 16 infants using resting state functional MRI (fMRI), which enables researchers to measure brain activity by detecting changes in blood flow. With resting state fMRI, the connectivity between neural regions--known as resting state networks--can be observed while the brain is at rest.

The research team, led by Dr. Radhakrishnan, investigated the functional connectivity of the amygdala, a region responsible for the perception and regulation of emotions such as anger, fear, sadness and aggression.

The study group included 16 full-term infants, including eight exposed to opioids prenatally and eight who were not exposed to prenatal opioids, or opioid naive. Imaging, including fMRI and anatomical MRI, was performed while the infants were naturally asleep.

To determine the participation of the amygdala in the resting state networks, the team created brain maps and applied regions of interest for the left and right amygdala.

"Our early results show significant differences in the way the amygdala connects to different brain regions between the infants exposed to opioids and the opioid-naive infants," Dr. Radhakrishnan said. "We still need to study what the clinical implication of this finding may be."

Dr. Radhakrishnan said larger and long-term outcome studies are underway to better understand the functional brain changes in prenatal opioid exposure and their associated long-term developmental outcomes.

"Although our early results showed differences between the two groups in a small study sample, it is very important that we further investigate and validate these findings in larger studies," she said. "In order to identify the best methods for managing NAS and improving long-term outcomes in these infants, it is critical to understand changes in brain function that may result from exposure to opioids prenatally."

Nonpowder firearms have long been marketed to children and teenagers as toys or "starter" firearms and include BB, pellet, airsoft and paintball guns. A new study conducted by researchers at the Center for Injury Research and Policy of the Abigail Wexner Research Institute at Nationwide Children's Hospital investigated nonpowder firearm injuries treated in U.S. emergency departments (EDs) among children younger than 18 years from 1990 through 2016. It found an overall decrease in the rate of nonpowder firearm injuries during the study period, but an increasing rate of eye injuries related to nonpowder firearms.

The study, published today in Pediatrics, found an estimated 364,133 children were treated in U.S. EDs for injuries related to nonpowder firearms during the study period, going from 16,456 injuries in 1990 to 8,585 injuries in 2016. BB guns accounted for 81% of the injuries. While the number of injuries decreased by 48% during the study period, in 2016 there was still a child treated every hour in the U.S.

"While it is good to see that the overall number of injuries from nonpowder firearms is going down, it is important to note that they remain a frequent and important source of preventable and often serious injury to children," said Gary Smith, MD, DrPH, senior author of the study and director of the Center for Injury Research and Policy at Nationwide Children's. "The severity and increasing rate of eye injury related to nonpowder firearms is especially concerning. One way to help reverse this trend is to make sure that protective eyewear is worn every time nonpowder firearms like BB, pellet, airsoft and paintball guns are used."

Eye injuries accounted for 15% of nonpowder firearm injuries and the number of eye injuries increased by 50% during the study period. These injuries were often serious, with 22% requiring admission to the hospital. The most common eye injury-related diagnoses were corneal abrasion (35%), hyphema (13%), globe rupture (10%) and foreign body (9%). These injuries can result in serious adverse outcomes, including partial or complete vision loss.

The average age of children with a nonpowder firearm injury was 12 years. Among cases where the type of firearm could be determined, BB guns accounted for 81% of injuries, followed by pellet guns (16%), paintball guns (3%) and airsoft guns (

"Nonpowder firearms can cause permanent, severe disability and even death," said Dr. Smith. "They are more powerful than many people think and some can achieve a muzzle velocity similar to a handgun. Stricter and more consistent safety legislation at the state level, as well as more child and parental education regarding proper supervision, firearm handling, and use of protective eyewear are needed."

State safety regulations for nonpowder firearms vary greatly, and frequently can be easily circumvented. The variability in regulations includes the age cutoff for child access, with some applying to children younger than 18 years of age and others only to those younger than 12 years of age. There are currently no federal safety regulations for nonpowder firearms, but two voluntary standards have been adopted and manufacturers generally comply with the safety specifications included in these standards.

Two genes that appear to help stem cells in the intestine burn dietary fat may play a role in colon cancer, according to a Rutgers study.

The study, published in the journal Gastroenterology, describes a new connection between the way cells consume fat and how genes regulate stem cell behavior in the intestines of mice.

"This is important because scientists have shown that when there's too much dietary fat in the intestine, stem cell numbers increase, boosting susceptibility to colon cancer," said senior author Michael Verzi, an associate professor in the Department of Genetics in the School of Arts and Sciences at Rutgers University-New Brunswick. Verzi is also a research member in the Genomic Instability and Cancer Genetics Research Program at Rutgers Cancer Institute of New Jersey.

People naturally lose millions of intestinal cells daily, much like they lose skin cells. Intestinal stem cells undergo constant renewal and fuel the continuous turnover of the lining of the intestine, but altered stem cell functions can lead to colon cancer.

Colorectal cancer (of the colon or rectum) is the third most common cancer diagnosed in both men and women in the United States. An estimated 101,420 Americans will be diagnosed with colon cancer this year, according to the American Cancer Society.

Recent studies have shown that intestinal stem cells can increase in animals on a high fat "Western" diet, potentially explaining an elevated cancer risk from such a diet.

The Rutgers team recently discovered that two genes (HNF4A and HNF4G) work together to promote the proper function of the intestinal lining. In the new study, they found that mice lost intestinal stem cells when these genes were inactivated, confirming their importance. Rutgers scientists believe that the genes help stem cells burn fat, providing them energy.

Going forward, the researchers hope to further investigate whether the two genes alter stem cell numbers and cancer risk during a high fat diet, said Verzi, who is also a member of the Rutgers Center for Lipid Research.

Researchers from the Mechanobiology Institute (MBI) at the National University of Singapore have shown that cells can attach to the fibrous protein meshwork that surrounds them only if the fibres are spaced close enough. The team's findings, which can explain the abnormal motility patterns displayed by cancer cells, were published in the science journal Nature Materials in September 2019.

The human body is made up of around a trillion cells. These cells stick to a supportive surface underneath (also known as matrix) as well as to the cells next to them.

Cell sticking forms the basis for the organisation of tissues, organs, and organ systems in multicellular organisms. Cells sticking to the matrix is essential for controlling important cell functions, including how much they move within the tissue. When this sticking is partially or completely lost, cells start to move erratically, a characteristic that is hallmark of metastatic cancers.

Cells also use sticking to know more about the physical and chemical nature of the matrix. Any disruption to how this information is relayed can lead not just to cancers, but many other serious diseases including those that affect the heart and the nervous system.

Hence, cell sticking can have major implications on health and diseases. This has spurred research on the topic, and over the past few decades many labs from all around the world have investigated the proteins and mechanisms involved in cell sticking. Researchers today now know that proteins at the cell periphery physically interact with proteins found in the matrix and these molecular connections basically are the attachment points between the cell and the matrix.

In the matrix, proteins mainly exist as fibres, which are arranged into a complex meshwork. Binding of the cell periphery proteins to this fibrous meshwork is a complex process, as several factors, such as the composition, density, and pattern of fibres can play a role.

In order to understand this complexity, imagine yourself walking on a net. The ease with which you can walk will mainly depend on how close the ropes of the net are: in essence, they must be patterned so as to provide sufficient footholds for support.

This analogy, when applied to cells, led to the hypothesis that cell periphery proteins would bind to matrix fibres and initiate cell sticking only if the fibres are arranged in a manner that offers sufficient footholds for binding. The study carried out in the Sheetz Lab at MBI investigated this important idea by trying to find out if fibre spacing could actually control cell sticking.

The study was led by MBI's Senior Research Fellow Dr Rishita Changede together with Principal Investigator Professor Michael Sheetz, along with collaborators from Columbia University. The team created artificial nanometre-sized fibres and arranged them in various 1D or 2D patterns that differed in the spacing between the fibres; these artificial fibres mimicked protein fibres found in the matrix. They then grew connective tissue cells known as fibroblasts on these artificial fibres and used advanced microscopes to compare the extent of cell sticking to the various patterns.

Based on their observations, the researchers drew one important conclusion - the spacing between the fibres is crucial for efficient cell sticking. Cells can stick strongly to the matrix when adjacent fibres are spaced closer than 160 nanometres apart. If this spacing was increased, cells cannot stick to the fibres.

To understand how diseases like cancers evolve is like trying to solve one complex jigsaw puzzle with several pieces still missing. By showing how fibre spacing could control cell sticking, the study unravels yet another important piece of the puzzle relating to cell adhesion and movement and allows scientists to better understand what could be going wrong and identify molecular pathways that could be used as therapeutic targets for treating these diseases.

From a clinical perspective, the critical role of fibre spacing described here can be applied to design customised artificial surfaces for use in regenerative medicine. This breakthrough medical technology enables the regeneration of damaged cells, tissues, or organs for therapeutic use. Controlling fibre spacing on artificial surfaces could optimise cell sticking and growth, enhancing the regeneration efficiency of these cells. The higher yield of restored, healthy cells thus obtained could be used for the treatment of patients with life-threatening or debilitating health conditions.

WASHINGTON, D.C. (Nov. 25, 2019) - Majorities of Americans say the federal government is doing too little for key aspects of the environment. And most believe the U.S. should focus on development of alternative sources of energy over expansion of fossil fuels, according to a new Pew Research Center survey.

The survey, conducted Oct. 1-13 among 3,627 U.S. adults using the Center's American Trends Panel, finds that 67% of U.S. adults say the federal government is not doing enough to reduce the effects of climate change, and similar shares say the same about government efforts to protect air or water quality. While there is strong consensus among Democrats on the need for more government efforts to reduce the effects of climate change, Republican views are divided along ideological, generational and gender lines.

A majority of moderate or liberal Republicans (65%, including GOP-leaning independents) say the federal government is doing too little to reduce the effects of climate change. In contrast, 24% of conservative Republicans say the same. A divide can also be seen by age; 52% of Millennial and Gen Z Republicans, ages 18 to 38 in 2019, say the government is taking too little action on climate, a higher share than of either Gen X (41%) or Baby Boomer and older Republicans (31%). Republican women (46%) also are more inclined than GOP men (34%) to think the government is doing too little to reduce the effects of climate change.

Other key findings include:

Most Americans say they are taking at least some action in their daily lives to protect the environment.

80% of Americans report that they reduce their food waste for environmental reasons. Large shares of the public say they use fewer plastics that cannot be reused such as plastic bags, straws or cups (72%) or reduce their water use (68%) to help the environment.

51% of Americans say they drive less or use carpools, while 41% say they eat less meat for environmental reasons.

Asked about how much individual actions matter, 67% of Americans say using fewer single-use plastics makes a big difference for the environment. About half say the same about cutting back on personal vehicle use (52%), limiting food waste (52%) or limiting water consumption (50%). A quarter of Americans (24%) say people eating less meat makes a big difference for the environment, 38% say it makes a small difference and another 38% think this makes almost no difference for the environment.

Most Americans favor expanding renewable energy sources, but divides remain over expanding offshore drilling and nuclear power.

92% of U.S. adults favor expanding solar power and 85% favor more wind power. The public is evenly divided over whether to expand nuclear power (49% on each side). Fewer than half of Americans support more offshore oil and gas drilling (42%), hydraulic fracturing for oil and natural gas (38%) or coal mining (35%).

Support for more nuclear power plants is up 6 percentage points from 2016, and support for coal mining is down 6 points. Democrats' support for offshore drilling and hydraulic fracturing has gone down over that period; support for both energy sources has stayed about the same among Republicans.

On balance, 77% of Americans think the more important energy priority for the country should be developing alternative energy sources rather than increasing U.S. production of fossil fuels.

90% of Democrats believe the U.S. should prioritize alternative energy development over expanded oil, coal and natural gas exploration and production. While a majority of Republicans also prioritize alternative energy sources, Republican views of this issue differ by ideology, generation and gender.

How Americans view the impact of climate change depends on where they live.

A majority of Americans (62%) say that climate change is affecting their local community either a great deal or some. That figure remains fairly steady from last year, when 59% reported at least some local effects of climate change.

Americans in Pacific states are most likely to see at least some local impacts of climate change (72%). By comparison, 54% of those living in Mountain states say climate change is affecting their local area at least some.

Those living in Western states stand out as particularly likely to report increasing frequency of wildfires or droughts/water shortages as local effects of climate change. Large shares in each region nationwide who report at least some local impact of climate change cite long periods of unusually hot weather as a major impact of climate change where they live.

Respondents living within 25 miles of a coastline anywhere in the U.S. are modestly more inclined to say that climate change is having at least some effect in their community; 67% of this group says this compared with 59% of those living at least 300 miles inland who say the same.

Political groups remain divided over climate change causes and policies.

Overall, 49% of Americans say human activity contributes a great deal to climate change and another 30% say human actions have some role in climate change. Two-in-ten (20%) believe human activity plays not too much or no role at all in climate change. At the same time, a majority of Americans say that natural patterns in the Earth's environment contribute to climate change a great deal (35%) or some (44%). Just 4% of Americans say that neither human activity nor natural patterns in the Earth's environment contribute to global climate change at least some.

84% of liberal Democrats say human activity contributes a great deal to climate change, with near consensus among this group that human activity contributes at least some amount to climate change (96%).

53% of conservative Republicans say human activity contributes a great deal (14%) or some (39%) to climate change. Another 45% of this group says human actions play not too much or no role in climate change.

81% of liberal Democrats say climate policies result in net benefits for the environment. Also, most (90%) think they either help or have no effect on the economy.

Conservative Republicans stand out as particularly skeptical about the benefits of climate policies for the environment. A minority of this group (25%) says such policies do more good than harm for the environment, and a majority (62%) says these policies hurt the economy.

The margin of sampling error for the full sample is plus or minus 2.1 percentage points.

Global simulations suggest plankton and fish species are showing resilience to climate change by going deeper underwater or moving to higher latitudes.

Anticipating changes in community composition in response to warming is challenging because species respond differently and the interactions change between them. However, a new study published in Nature Climate Change shows how changes in marine communities tightly follow ocean warming as the number and abundance of warm-water species increase whereas those of cold-water species decrease.

"Identifying aspects of community change that can be monitored and forecasted is crucial to better inform management to environmental changes," explains Jorge García Molinos of Hokkaido University's Arctic Research Center, one of the authors of this study.

Led by Professor Michael Burrows of the Scottish Association for Marine Science (SAMS), an international team of researchers from the UK, Japan, Australia, USA, Germany, Canada, South Africa and New Zealand analysed three million records of thousands of species from standardized international surveys dating back to 1985 to assess how ocean warming is affecting the composition of fish and plankton communities across the northern hemisphere in relation to the thermal tolerances of their constituent species.

In rapidly warming waters, like the North Atlantic, the team found strong shifts towards a dominance of warm-water species, replacing their cold-tolerant counterparts. These changes were less pronounced in regions with stable temperatures, including the Northeast Pacific and the Gulf of Mexico. Marine communities most sensitive to warming are composed of species with diverse thermal preferences and narrow thermal tolerance ranges.

However, in some regions experiencing rapid surface warming, like the Labrador Sea, communities were less responsive than expected. These regions are characterized by strong temperature depth gradients (up to 5°C for 100m depth), allowing some of the cold-water species to cope with warming by redistributing towards deeper waters.

"This finding reminds us that life in the ocean, and the impacts of climate change on it, span a truly three-dimensional world. Yet, we still tend to simplify the situation by looking at these issues in two dimensions, something that may lead to the wrong conclusions," García Molinos says.

The scientists say these strong, predictable effects of recent temperature change on marine community composition, operating through species thermal affinities, provide a benchmark for measuring how fast global biodiversity is restructuring itself as a result of climate change on regional to ocean scales.

Do bad dreams serve a real purpose? To answer this question, researchers from the University of Geneva (UNIGE) and University Hospitals of Geneva (HUG), Switzerland, - working in collaboration with the University of Wisconsin (USA) - analysed the dreams of a number of people and identified which areas of the brain were activated when they experienced fear in their dreams. They found that once the individuals woke up, the brain areas responsible for controlling emotions responded to fear-inducing situations much more effectively. These results, which are published in the journal Human Brain Mapping, demonstrate that dreams help us react better to frightening situations, thereby paving the way for new dream-based therapeutic methods for combating anxiety.

Neuroscience has been taking an interest in dreams for a number of years, focusing on the areas of the brain that are active when we dream. The scientists employed high-density electroencephalography (EEG), which uses several electrodes positioned on the skull to measure brain activity. They recently discovered that certain regions of the brain are responsible for the formation of dreams, and that certain other regions are activated depending on the specific content within a dream (such as perceptions, thoughts and emotions). "We were particularly interested in fear: what areas of our brain are activated when we're having bad dreams?» states Lampros Perogamvros, a researcher in the Sleep and Cognition Laboratory headed by professor Sophie Schwartz in the Department of Basic Neurosciences, Faculty of Medicine, UNIGE, and senior clinical lecturer at HUG's Sleep Laboratory.

Brain areas active during frightening dreams

The scientists from Geneva placed 256 EEG electrodes on 18 subjects whom they woke several times during the night. Each time the participants were woken up, they had to answer a series of questions such as: 'Did you dream? And, if so, did you feel scared?'

"By analysing the brain activity based on participants' responses, we identified two brain regions implicated in the induction of fear experienced during the dream: the insula and the cingulate cortex", explains Perogamvros. The insula is also involved in evaluating emotions when awake, and is automatically activated when someone feels afraid. The cingulate cortex, for its part, plays a role in preparing motor and behavioural reactions in the event of a threat. "For the first time, we've identified the neural correlates of fear when we dream and have observed that similar regions are activated when experiencing fear in both sleep and wakeful states", continues the Geneva-based researcher.

Do dreams prepare us for our waking lives?

The researchers then investigated a possible link between the fear experienced during a dream and the emotions experienced once awake. They gave a dream diary to 89 participants for the duration of a week. The subjects were asked that each morning upon waking, they note down whether they remembered the dreams they had during the night and to identify the emotions they felt, including fear. At the end of the week, they were placed in a magnetic resonance imaging (MRI) machine. "We showed each participant emotionally-negative images, such as assaults or distressful situations, as well as neutral images, to see which areas of the brain were more active for fear, and whether the activated area changed depending on the emotions experienced in the dreams over the previous week," says Virginie Sterpenich, a researcher in the Department of Basic Neurosciences at UNIGE.

The researchers were particularly interested in the brain areas traditionally involved in managing emotions, such as the insula, amygdala, medial prefrontal cortex and cingulate cortex. "We found that the longer a someone had felt fear in their dreams, the less the insula, cingulate and amygdala were activated when the same person looked at the negative pictures", says Sterpenich. "In addition, the activity in the medial prefrontal cortex, which is known to inhibit the amygdala in the event of fear, increased in proportion to the number of frightening dreams!"

These results demonstrate the very strong link between the emotions we feel in both sleep and wakefulness. They also reinforce a neuroscientific theory about dreams: we simulate frightening situations while dreaming in order to better react to them once we're awake. "Dreams may be considered as a real training for our future reactions and may potentially prepare us to face real life dangers," suggests Perogamvros.

Dreams: a new therapeutically?

Following the revelation of a potential function of dreams, the researchers are now planning to study a new form of dream therapy to treat anxiety disorders. They are also interested in nightmares, because - unlike bad dreams, in which the level of fear is moderate - nightmares are characterised by an excessive level of fear that disrupts sleep and has a negative impact on the individual once awake. "We believe that if a certain threshold of fear is exceeded in a dream, it loses its beneficial role as an emotional regulator," concludes Perogamvros.

Climate change is reshaping communities of fish and other sea life, according to a pioneering study on how ocean warming is affecting the mix of species.

The study, published in the journal Nature Climate Change, covers species that are important for fisheries and that serve as food for fish, such as copepods and other zooplankton.

"The changes we're observing ripple throughout local and global economies all the way to our dinner plates," said co-author Malin Pinsky, an associate professor in the Department of Ecology, Evolution, and Natural Resources in the School of Environmental and Biological Sciences at Rutgers University-New Brunswick.

"We found dramatic evidence that changing temperatures are already reshaping communities of ocean organisms," Pinsky said. "We found that warm-water species are rapidly increasing and cold-water marine species are decreasing as the global temperature rises. Changes like this are often disrupting our fisheries and ocean food chains."

An international team of scientists also found evidence that species in some places can avoid declines by seeking refuge in cooler, deeper water - like plants on land that move to higher elevations to avoid heat, Pinsky said.

The scientists compiled the most comprehensive assessment of how ocean warming is affecting the mix of species in our oceans. They looked at fishes, invertebrates such as crabs and other crustaceans and plankton in the North Atlantic and North Pacific, across two continents and two oceans. They analyzed three million records of thousands of species from 200 ecological communities across the globe from 1985 to 2014.

Regions with stable temperatures (the Northeast Pacific and Gulf of Mexico, for example) show little change in species dominance, while warming areas (the North Atlantic, for example) are experiencing strong shifts toward the dominance of warm-water species, the study says.

Temperature is a fundamental driver for change in marine systems, with restructuring of communities in the most rapidly warming areas. Still, the data "suggest a strong prognosis of resilience to climate change for these communities," the study says.

"We're now trying to understand how the changes we see in the ocean compare with those on land and in freshwater ecosystems," said Pinsky, who is also a sabbatical professor at the German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig.