Culture

The El Niño-Southern Oscillation has been responsible for widespread, simultaneous crop failures in recent history, according to a new study from researchers at Columbia University's International Research Institute for Climate and Society, the International Food Policy Research Institute (IFPRI) and other partners. This finding runs counter to a central pillar of the global agriculture system, which assumes that crop failures in geographically distant breadbasket regions such as the United States, China and Argentina are unrelated. The results also underscore the potential opportunity to manage such climate risks, which can be predicted using seasonal climate forecasts.

The study, published in Science Advances, is the first to provide estimates of the degree to which different modes of climate variability such as ENSO cause volatility in global and regional production of corn, wheat and soy. Such variability caused nearly 18 percent volatility in global corn production from 1980 to 2010, for example.

"Global agriculture counts on the strong likelihood that poor production in one part of the world will be made up for by good production elsewhere," said Weston Anderson, a postdoctoral research scientist at the International Research Institute for Climate and Society and lead author on the study.

Of course, there's always a chance--however small--that it won't. The assumption until now has been that widespread crop failures would come from a set of random, adverse weather events, Anderson said.

He and his co-authors decided to test this idea by looking at the impact that the El Niño-Southern Oscillation, the Indian Ocean Dipole, and other well-understood climate patterns have had on global production of corn, soybeans and wheat. They analyzed how these modes of climate variability influenced drought and heat in major growing regions.

"We found that ENSO can, and has, forced multiple breadbasket failures, including a significant one in 1983," said Anderson. "The problem with pooling our risk as a mitigating strategy is that it assumes failures are random. But we know that strong El Niño or La Niña events in effect organize which regions experience drought and extreme temperatures. For some crops, that reorganization forces poor yields in multiple major production regions simultaneously."

How important is the influence of climate variability? The authors found that, on a global level, corn is the most susceptible to such crop failures. They found that 18% percent of the year-to-year changes in corn production were the result of climate variability. Soybeans and wheat were found to be less at risk for simultaneous failures, with climate variability accounting for 7% and 6% of the changes in global production, respectively.

"The bigger the uncertainty around climate drivers, the bigger the risk for those involved in the food systems," said co-author Liangzhi You, a senior research fellow at the International Food Policy Research Institute. "The worst affected are poor farmers in developing countries whose livelihoods depend upon crop yields as they do not have an appetite for risks in absence of formal insurance products or other coping mechanisms." The risk is further exacerbated by challenges posed by lack of infrastructure and resources in developing countries.

"ENSO may not be important in all years, but it is the only thing we know of that has forced simultaneous global-scale crop failures" said Anderson.

Within specific regions, the risk to agriculture by climate variability can be much higher. For example, across much of Africa and in Northeast Brazil, ENSO and other recurring climate phenomena accounted for 40-65% of the ups and downs of food production. In other regions, the number was as low as 10%.

While on the surface this may appear to mean that those areas more affected by ENSO and other climate patterns are more at risk to extreme events, the numbers actually reflect a link to climate patterns that can be monitored and predicted.

"What excites me about this work is that it shows how predictable modes of climate variability impact crop production in multiple regions and can scale up to influence global production, said co-author Richard Seager of Columbia's Lamont Doherty Earth Observatory. "This should allow anticipation of shocks to global food prices and supplies and, hence, improve efforts to avoid food insecurity and provide emergency food assistance when needed."

In Gallium Nitride (GaN) implanted with a small amount of magnesium (Mg), NIMS succeeded for the first time in visualizing the distribution and optical behavior of the implanted Mg at the nanoscale which may help in improving electrical performance of GaN based devices. Some of the mechanisms by which introduced Mg ions convert GaN into a p-type semiconductor are also revealed. These findings may significantly expedite the identification of optimum conditions for Mg implantation vital to the mass production of GaN power devices.

The development of GaN based power devices--a promising energy-saving technology--requires fabrication of both n- and p-type GaN semiconductors. p-type GaN semiconductors can be mass produced by introducing Mg ions into GaN wafers and subjecting the wafers to thermal treatment. However, no method existed for assessing the effect of Mg concentrations and thermal treatment temperature on the distribution and optical behavior of Mg implanted into GaN at nanoscale dimensions. In addition, the mechanisms by which p-type GaN forms remained unclear so far. These issues had been hindering the development of technologies enabling mass production of GaN devices.

For this research, we prepared slanted cross-sections of Mg ion-implanted GaN wafers by polishing the wafers at an angle and analyzed the distribution of luminescence intensity on the cross-sections using a cathodoluminescence technique. As a result, we found that Mg atoms implanted several tens of nanometers beneath the wafer surface had been activated while those immediately below the surface had not been activated (figure at left). In addition, we found using atom probe tomography that Mg atoms, when implanted in high concentrations, develop into either disc- or rod-shaped deposits depending on temperature (figure at right). The integration of different analytical results generated by these latest microscopy techniques indicated that Mg atoms implanted in the vicinity of the wafer surface may develop into deposits under certain temperature conditions, and thus prevents them from activating.

The results of this research have provided vital guidance for the development of ion-doped p-type GaN layers. Furthermore, the techniques developed during this project for the analysis of impurity distributions are applicable not only in homogeneous wafers but also in GaN device materials with varying structures. The use of these techniques may therefore speed the development of high-performance GaN devices.

A new study soon to appear in the Faculty of Public Health's Journal of Public Health suggests that participating in local food projects may have a positive effect on wellbeing and psychological health.

Local food is a growing movement, and includes initiatives such as allotments, community gardens, community supported agriculture, farmers' markets, and food buying cooperatives. Consumers are increasingly interested in where their food comes from. Retail sales of local food have grown significantly over the past decade, as has participation in farmers' markets, community supported agriculture schemes, and buying cooperatives.

Research has explored the physical health benefits of growing food, but has not so far systematically explored how local food projects may influence psychological well-being. Mental illness presents a growing global public health crisis. In the United Kingdom, mental health contributes to 28% of the total financial cost of healthcare. Psychological wellbeing generates important bene?ts for people and societies, including good health, longevity, improved personal relationships, better productivity, and civic engagement.

Using an on-line survey, researchers compared participants of local food initiatives across three English counties - Essex, Norfolk, and Suffolk - with members of the wider public. They found that those who participated in local food initiatives scored higher on standardised measures of well-being than those who did not participate. They also explored why this might be the case, looking at four different mediators known to influence well-being: connection to nature, the satisfaction of basic psychological needs, better diets, and physical activity. Finally, they explored how different types of participation - such as for longer durations or in more active roles - influence well-being.

"These findings are encouraging to those of us looking at how sustainability and well-being interact," said Zareen Bharucha, the study's lead researcher. "They show that we should be looking more seriously at projects such as allotments, community gardens, community supported agriculture, and farmers' markets, which can bring people together, improve diets, improve connection to nature, and help people learn new things. All of these help to improve mental health, which is one of the most significant public health challenges of our time. At the same time, they help build the foundations of a really sustainable food system, which is also fundamental for the well-being of people and the planet."

Human cytomegalovirus (HCMV) may not be a household name as far as viruses go, but according to Xiaoping Zhu, professor and chair in Veterinary Medicine at UMD, half of the population walking around campus is likely to be a carrier. Once contracted, it lays dormant in your body for the rest of your life and can flare up whenever your immune system is severely compromised, giving you flu-like symptoms. This becomes a severe problem for people who already have weakened immune systems, for example the very young, old, pregnant women, organ transplant recipients, or HIV/AIDS patients. More concerning, however, is that HCMV is the number one infectious cause of congenital birth defects in the world, including developmental disabilities and deafness. But how can a protein be a major contributor in the development of birth defects, and also hold the potential to provide symptom relief from autoimmune diseases like lupus? In a new paper published in Nature Communications, Zhu and his colleagues are helping to answer this question and uncover the mechanisms that will lead to multi-faceted prevention and treatment.

"HCMV stays asleep inside our cells," explains Zhu. "Then one day, you get stressed, you have too much going on, and your immunity decreases allowing the virus to spring up again." This is the case with all strains of the herpes virus like HCMV, chickenpox, and herpes simplex. HCMV can present similar symptoms to the flu virus. But unlike the flu, it persists in your body, and your immune system has to work harder than normal to combat the virus and keep it at bay.

It can also be passed through the placenta to a pregnant mother's unborn child, not only affecting the child's immune system, but also potentially causing birth defects. "When the mother gets infected, the virus spreads from mother to baby and can cause mental disabilities, vision loss, and deafness. People are aware of this concern with Zika virus for instance, but Zika doesn't stay in your system for life like HCMV, and it isn't present in 50 to 80 percent of the population globally depending on where you live," says Zhu.

This makes the study of HCMV and the mechanisms that contribute to its persistence and transmission a high priority for the medical community, with National Institutes of Health (NIH) funding Zhu's work. The immune system has two arms of immunity, at the cellular and antibody levels, to specifically destroy bugs. The mechanisms of the US11 protein that allow HCMV to evade white blood cells that kill viruses on the cellular level are well known, but in this latest publication from Zhu, he and his colleagues discuss a newly discovered function of the same protein that impairs antibody immunity. Antibody immunity normally prevents viruses from entering and infecting uninfected cells and labels the infected cells to be destroyed by the white blood cells. But US11 attacks a specific receptor that not only naturally bolsters your immunity, but also directs protective antibodies from the mother to be transferred to the fetus. With this receptor impaired, HCMV may reduce transmission of these critical antibodies, resulting in vulnerability to all sorts of birth defects, and at the very least compromising the child's immunity throughout their life.

"This is the first time that we discovered that this virus, or any pathogen, has this strategy to destroy this receptor function and reduce antibody functionality," says Zhu. "Antibodies are also used to treat diseases like AIDS, cancer, and make vaccines, and this mechanism makes that less effective. By understanding this function, we can hopefully figure out methods to block that mechanism in the future."

Beyond prevention for birth defects and immune system dysfunction, Zhu sees another potential treatment benefit for this mechanism for patients struggling with autoimmune diseases. "Humans have many autoimmune diseases, and in these cases like with lupus, it is actually our immune response that causes the disease, which is regulated by antibodies," explains Zhu. "In these patients, we are concerned with how to reduce autoimmune antibodies, because their overproduction causes damage on our own tissues and cells, swelling in the joints, and substantial pain. Since this protein US11 can facilitate antibody degradation and suppress antibody function, it could be used in humans to treat autoimmune disease and target these disease-causing antibodies to indirectly benefit patients with immune diseases."

This therapeutic prospect is being patented by UMD through Zhu and Xiaoyang Liu, who stress the importance of directly translating basic research like this into applied outcomes and treatment options, not just for humans, but for animals that are infected with similar viruses as well. "Human and animal health research is interconnected," says Zhu. "Similar knowledge can be used to promote animal and human health, and diseases pass directly from animals to humans and vice versa."

With humans and animals standing to benefit from this work in many different ways, the applications of this discovery are widespread. The full paper, entitled "Human cytomegalovirus evades antibody-mediated immunity through endoplasmic reticulum-associated degradation of the FcRn receptor," is available through Nature Communications.

Parents who financially help their unemployed adult children offset such costs by adjusting their behavior, particularly by spending less money on food, working more and reducing retirement savings, according to a new RAND Corporation study.

It is known that parents are increasingly helping their adult children, including by letting them live at home and providing them money and other assistance. Little, though, has been documented on the economic impact of such decisions on parents themselves.

This study, published today in the IZA Journal of Labor Economics, sheds light on exactly how parents curb own behavior - to their own financial detriment - when they provide financial assistance to an unemployed adult child.

"One may assume that since parents willingly help their children, they are not worse off because of that decision," said Kathryn Edwards, an associate economist and lead author of the study. "But our research shows that that these decisions may not result in the best financial outcome for the parent."

Researchers examined the effect of a child's unemployment (of at least one week) on parents' financial assistance to the child, as well as the parents' household food consumption, income and savings.

When it comes to financial assistance, parents are more likely to give cash to a child once they lose their job, the study found. Researchers also determined that parents spend less money on food once a child becomes unemployed and maintain this drop in consumption for a two-year period.

Also striking is the change in parents' work and saving habits. Parents work more the year their child becomes unemployed. Some parents also decrease savings for retirement.

"On the individual level, most of the changes were small," Edwards said. "The problem is what this means in the aggregate. When the labor market risk of one generation is informally insured by another, the older generation may be putting their retirement security at risk, while the younger generation has insurance that depends on how willing and wealthy their parents are. This is a trademark of basic economic inequality."

The research is based on an analysis of 4,500 mother-child pairs gleaned from the Panel Study of Income Dynamics, a longitudinal sample of U.S. households. (Researchers were able to match mothers at a higher rate than fathers and most of the matched fathers were in households with previously matched mothers.)

Researchers at the Modern Diet and Physiology Research Center and Department of Pediatrics at Yale School of Medicine are investigating whether insulin delivered directly to the brain by nasal inhalation can enhance communication between brain regions and improve cognition in adolescents with obesity and prediabetes. Led by Dr. Dana Small, preliminary findings from a two-year study suggest that intranasal insulin improves brain and cognitive function in adolescents with obesity.

Insulin is primarily recognized for its role in regulation of blood sugar and metabolism. But insulin also travels to the brain where it influences a wide range of functions including memory, mood, and appetite. In type 2 diabetes, cells throughout the body become insensitive to insulin and when this happens in the brain, it may lead to cognitive impairment and an increased risk of developing dementia later in life..

Capitalizing on the fact that intranasal inhalation of insulin delivers insulin directly to the brain, Dr. Small and her team are investigating the link between brain insulin sensitivity and cognitive function in adolescents with obesity. Preliminary cross-sectional findings presented this week at the annual meeting for the Society for the Study of Ingestive Behavior in Utrecht, Netherlands, found that intranasal insulin delivery improved performance on a memory task in adolescents with high BMI. Compared to inhalation of a placebo, the intranasal insulin also significantly increased connectivity between left and right dorsolateral prefrontal cortex - key brain areas for cognitive performance and cognitive control.

While data collection is ongoing, the preliminary cross-sectional findings suggest that not only is obesity associated with poorer memory, but that this impairment can be reversed by intranasal insulin. The researchers plan to continue this work to better understand the role of factors such as body fat levels and diabetic status on neurocognition, as well as evaluation of the effects of changes in these measures over time.

Every-other-day fasting substantially reduces the likelihood of developing type 2 diabetes in mice eating a fat-rich diet, according to new research out of the German Institute of Human Nutrition Potsdam-Rehbruecke. These findings, presented this week at the annual meeting of the Society for the Study of Ingestive Behavior in Utrecht, Netherlands, suggest that periodic fasting can reduce fat accumulation in the pancreas and, in turn, prevent the onset of type 2 diabetes. "We observed that pancreatic fat cells directly affect islet insulin secretion and that this can be altered by eating patterns" said Dr. Mandy Stadion, a post-doctoral research fellow who led this study.

"It is well known that a fatty liver promotes the development of type 2 diabetes and that intermittent fasting improves insulin sensitivity by reducing liver fat in mice and men," explained Professor Annette Schürmann, head of the Department Experimental Diabetology at the German Institute of Human Nutrition and senior author of the study. "However, little is known about the formation of fat cells in the pancreas during obesity, their detailed impact on islet-cell function and whether intermittent fasting can prevent a fatty pancreas."

For these studies the researchers provided one group of diabetes-prone mice with unlimited access to a high-fat diet. These mice were subjected to food restriction every other day (intermittent fasting). Compared to the control condition, intermittent fasting resulted in remarkably reduced pancreatic fat - similar to levels of diabetes-resistant mice - as well as in lower blood sugar levels and improved islet-cell function.

"We believe that the elevated insulin secretion of pancreatic islet cells, particularly from diabetes-prone mice, initiates a more rapid loss of function and finally islet cell-death,"explaned Schürmann. And while this loss of function ultimately contributes to the development of type 2 diabetes, the researchers are optimistic the finding that intermittent fasting can prevent the fat accumulation that leads to increased insulin may reveal a new path forward in the therapeutic prevention and treatment of diabetes.

How does the brain process rewards? Researchers at the University of Pennsylvania are investigating how the brain responds differently to two commonly ingested rewards - food and alcohol - to understand how they alter neural activity and behavior. Their findings were presented this week in Utrecht, Netherlands at the 2019 Annual Meeting of the Society for the Study of Ingestive Behavior (SSIB), one of the leading venues for research on eating and drinking.

In a study led by Dr. Amber Alhadeff, neural activity was measured in hungry mice consuming either food or alcohol. "Our modern neuroscience toolkit now allows us to monitor neural activity in behaving mice when we give them access to different kinds of rewards. This gives us unprecedented access into the mechanisms that control motivation and behavior," said Alhadeff. The study demonstrates that food and alcohol have similar effects on neurons that are known to be involved in food intake and reward. However, different pathways carry signals to the brain following ingestion of either food or alcohol. They found that the vagus nerve, a highway of information from the gastrointestinal tract to the brain, is responsible for transmitting food signals to "hunger neurons." Alcohol, on the other hand, does not utilize vagal signaling to communicate with these same hunger neurons, but likely accesses them, and suppresses their activity, directly through the bloodstream.

These divergent pathways of information flow could help explain why food and alcohol have different effects on our behavior, according to senior author Dr. J. Nicholas Betley. When the researchers measured how alcohol affects food intake, they unexpectedly found that it has little effect on feeding behavior, despite its significant calorie content. "When we observed this, we started to think that mice don't actually compute the caloric content of alcohol" said Betley. Indeed, the University of Pennsylvania team went on to show that stimulation of "hunger neurons" in the brain robustly drives food intake, but has no effect on alcohol intake. In the future, these findings will be useful for determining the different mechanisms through which food and drugs impact neural activity and motivation for different rewards, providing insight into the underpinnings of obesity and substance abuse.

Recent research suggests that the psychological consequences of being in a disadvantaged position in society may stimulate appetite and increase eating regardless of one's ability to access healthier foods. These findings, out from Nanyang Technological University in Singapore and the Singapore Institute for Clinical Sciences, add a new dimension to previous findings suggesting that the increased risk for obesity among people who are poorer and socioeconomically disadvantaged is due primarily to economic barriers that prevent access to healthier foods and other unhealthy behaviors associated with poverty.

These intriguing findings, presented by Dr. Bobby Cheon at the annual meeting of the Society for the Study of Ingestive Behavior this week, involved making research participants feel like they have inadequate socioeconomic resources compared to other people and measuring the effects on eating behaviors. Participants in the study were led to make comparisons of financial, economic, and social status resources (e.g., having a respected position in society) with others who were either much better off or much worse off than them. This approach of experimentally manipulating whether people perceive themselves as having sufficient or inadequate socioeconomic standing compared to others allowed the researchers to directly test whether the mere perception of socioeconomic disadvantage influences food preferences and eating behaviors.

Across multiple studies, the researchers found that participants who were led to feel they had fewer resources and opportunities compared to others ate more calories from snacks and meals offered during the experiment, served themselves larger portion sizes of foods, and showed increased ability to detect differences in calories between beverages. Participants who experienced feelings of socioeconomic disadvantage also had elevated levels of ghrelin - often referred to as the "hunger hormone" - providing a biological explanation for the desire to eat more under these conditions.

"If feelings of deprivation and inadequacy produced by perceived socioeconomic inequality can stimulate appetite and food intake, then it's possible that feeling that important needs in one's life have been satisfied may produce the opposite effect of reducing excessive food intake," said Cheon. To test this, research participants were assigned to complete a daily gratitude journal for 2 weeks, in which they listed things that they were grateful for each day. Compared to a control group that wrote about events that occurred each day, male participants in the gratitude journal group showed a reduction in desired portions of a variety of foods.

Although inadequate access to healthy foods is often blamed for obesity in populations with lower socioeconomic status, this research shows that the psychological consequences of social and economic inequality are also detrimental to health. The research team plans to continue to test methods, like heightening gratitude, to psychologically protect people from engaging in potentially unhealthy eating behaviors in response to perceived socioeconomic inequality and insecurities.

While pilots rely on radio signals, advanced computations and tools to keep them on course during strong crosswinds, birds can naturally navigate these demanding conditions - and do so in environments with little visibility. To understand how they accomplish this feat, researchers in the lab of David Lentink, assistant professor of mechanical engineering at Stanford University, studied lovebirds flying in a crosswind tunnel which features customizable wind and light settings.

This research, published July 9 in the Proceedings of the National Academy of Sciences, could inspire more robust and computationally efficient visual control algorithms for autonomous aerial robots.

This is the first study of how birds orient their bodies, necks and heads to fly through extreme 45-degree crosswinds over short ranges - both in bright visual environments and in dark, cave-like environments, where a faint point of light is the only visual beacon. To the researchers' surprise, the lovebirds navigated all environments equally well.

"It's amazing that lovebirds navigated 45-degree crosswinds even in our cave environment, because in their natural environment they fly in open habitats during the day," said Daniel Quinn, who worked as a postdoctoral fellow with Lentink and is now an assistant professor at the University of Virginia. "Even well-trained pilots rely on runway lighting, radio beacons and guidance from air traffic controllers to land safely on windy nights."

"The conditions we studied can cause spatial disorientation in pilots, yet the lovebirds aced their maneuvers in the dark as if there was no challenge," Lentink added. "This was a big surprise to the entire team because we studied 'naïve' lovebirds. They were bred and kept in an indoor cage and had no experience with flying in the wind. Their ability may thus well be innate."

The researchers found that lovebirds navigate by stabilizing and fixating their gaze on the goal, while yawing their bodies into the crosswind. Staying on course requires them to actively contort their necks by 30 degrees or more. A computer-simulated model informed by the experimental data indicated that, while neck control is active, body reorientation into the wind is achieved passively. Further tests with a simple mechanical bird model in a wind tunnel showed how well it works.

"Airplanes have a vertical tail to orient stably into the wind. We discovered why birds don't need one: their flapping wings don't only offer propulsion, they also orient into the wind passively like a weathervane" Lentink said.

But this is only half of the story. Simultaneously, the lovebirds actively twist their necks to orient their heads toward the light beacon. The amount of neck twist then gives the relative wind angle with respect to their goal direction. This twist angle is all the lovebirds need to control their flight toward the beacon. While doing this, they stabilize their heads remarkably well.

"Apparently, the direction of gravity sensed by the bird's vestibular system helps compensate for the missing wide-field visual horizon," Quinn said.

High-speed videos of the birds flying in the dark, filmed under infrared light, as well as the models explaining the behavior showed that birds don't need a wide-field visual horizon nor optic flow (motion of image intensity over the retina) to maneuver in crosswinds. This finding runs contrary to decades of lab-based locomotion and neuroscience studies in still air that suggested both were critical. The researchers still think that rich visual information, when available, plays a key role in the way birds combine all their sensory inputs, but the study revises the idea that it is essential.

Even in the strange world of open quantum systems, the arrow of time points steadily forward -- most of the time. New experiments conducted at Washington University in St. Louis compare the forward and reverse trajectories of superconducting circuits called qubits, and find that they follow the second law of thermodynamics. The research is published July 9 in the journal Physical Review Letters.

"When you look at a quantum system, the act of measuring usually changes the way it behaves," said Kater Murch, associate professor of physics in Arts & Sciences. "Imagine shining light on a small particle. The photons end up pushing it around and there is a dynamic associated with the measurement process alone.

"We wanted to find out if these dynamics have anything to do with the arrow of time -- the fact that entropy tends to increase as time goes on."

In a related video, Murch asks, "Do quantum movies look funny when you play them backwards?" He and his team, including Patrick Harrington, a graduate student in physics and first author of the paper, took that question to the lab -- where their work is part of the new Center for Quantum Sensors.

"We looked at microscopic movies of a quantum system's movement during measurement, and asked if the movies looked more likely when played forward or backwards; this comparison can be used to determine if entropy increases or not," Murch said. "We found that even at the microscopic scale, the second law seems to hold: entropy generally increases.

"This increase happens because we look at it -- the process of making the movie seemingly creates the arrow of time," he said.

Murch's research group is focused on understanding and controlling open quantum systems. While everyday objects obey the laws of classical mechanics, single particles of light or matter follow instead the laws of quantum physics. But these particles are not easily isolated, and as soon as they interact with the outside world they lose their quantum properties.

Murch is the 2018 recipient of a Cottrell Scholar Award and a National Science Foundation CAREER Award. The new research work featured in this video and publication is funded in part by his 2015 Alfred P. Sloan Research Fellowship.

EAST LANSING, Mich. - Some people are drawn to cologne; others are attracted to perfume. When it comes to sea lampreys, however, spermine smells like love.

In new research led by Michigan State University and published in the current issue of PLoS Biology, spermine, an odorous compound found in male semen, proved to be a powerful aphrodisiac.

Spermine isn't a new discovery. It's been a known quantity in semen since 1678 - at least in humans. Its tractor-beam effect on spawning female sea lampreys is new, however, and it can be yet another key way to potentially control the invasive species.

"We found the male ejaculate contains spermine, a highly specific and potent pheromone, which attracts only mature females," said Weiming Li, fisheries and wildlife professor and senior author of the study. "Mature females likely use spermine to identify males actively releasing sperm in the spawning aggregation."

They need this help because sea lampreys migrate up to river gravel beds ¬- spawning aggregation sites - drawn by other pheromones released from spawning males. These mating cues are merely the billboards, though, along riverine highways that draw them to the sites.

Arriving at the gravel bar of love, the females see many males on nests - all mature and ready to mate. Rather than find "the perfect mate," the females seem to act on localized cues and form promiscuous pairs with many males - in sequence and one at a time - and spawn several times per hour.

Spermine is a coup de gras that helps females make their final selections, navigate the throng of males and find the best ones with which to mate. According to Li, this is the first time scientists have been able to document this behavior in sea lampreys.

"We also were able to document a specific receptor in the noses of females that picks up spermine, and it can be smelled at trace-level concentrations," said Richard Neubig, pharmacology professor and study co-author. "This was a big job requiring nearly 12,000 tests in the MSU high-throughput screening lab to figure out the right pair of chemical and receptor."

Ovulatory females detect this faint cologne, and they respond at levels as low as 10-14 molar, a mere whiff comparable to a single drop of perfume in a pool. It's interesting to note that even higher levels of spermine had no effect on immature females or other males.

Li and a team of scientists identified the receptor for spermine, a trace-associated receptor, or TAAR, in females.
Future work will determine if spermine can be used to manage invasive sea lamprey populations. Likewise, MSU scientists will investigate the TAAR mechanism to explore its control potential.

Controlling sea lampreys in the Great Lakes is a critical goal of fisheries scientists. The invasive species infiltrated the upper Great Lakes via the Atlantic Ocean in the 1920s through shipping canals. They feed by attaching themselves to other fish, such as salmon and trout. One sea lamprey can kill more than 40 pounds of fish, and the U.S. and Canadian governments spend approximately $20 million annually to control them in the Great Lakes.

BOSTON - A study led by researchers at Boston Medical Center (BMC) found that symptom-triggered medication dosing for neonatal opioid withdrawal syndrome instead of infants receiving a fixed schedule of medication with a long taper reduced the length of their hospital stay. The findings, published in Hospital Pediatrics, indicate that following the novel symptom-triggered approach - developed at BMC - for administering medication could be a more effective intervention for these infants and could help reduce unnecessary medication exposure.

Neonatal Opioid Withdrawal Syndrome (NOWS) effects infants exposed to opioids in utero. With the increase in both unprescribed and prescribed opioids use in the U.S., which has not spared pregnant women, there has been a five-fold increase in the rate of NOWS over the past decade. Approximately 50 to 80 percent of opioid-exposed infants require medication to manage their symptoms of withdrawal, which usually appear two to three days after birth and can include irritability, trouble eating and sleeping, diarrhea, muscle rigidity, and difficulty soothing. Medications that are currently used to manage these symptoms include methadone, morphine, and buprenorphine. The average hospital stay for infants with NOWS who are treated with medication is 23 days and costs approximately $93,000.

During the postpartum hospitalization, all infants with NOWS are assessed based on their ability to eat, sleep and be consoled every four hours. At BMC, clinicians utilize non-pharmacologic care interventions, including parental presence at the bedside, breastfeeding, and rooming in, as first line treatment of NOWS, which studies have shown to reduce the need for medication and hospital length of stay, thus reducing costs. If an infant is having difficulties with these core functions after using the non-pharmacologic treatments, the health care team determines if medication is the appropriate next step.

In this study, for infants who required medication for NOWS, the researchers investigated two treatment approaches: between June 2016 and November 2017, the fixed schedule medication approach was used, in which methadone was dosed every eight hours with the traditional slow taper to treat NOWS. Between December 2017 and May 2018, the researchers implemented the symptom-triggered approach, which was developed by clinician researchers at BMC as a novel way to treat NOWS by focusing on treating symptoms and keeping the infants comfortable. This approach helps reduce the incidence of creating a dependence on the opioid medication, which can sometimes occur with the traditional fixed scheduled medication approach.

Infants who were treated using the symptom triggered approach had a median length of stay of 10.5 days, versus 17 days for the fixed schedule approach. The symptom triggered group had 5.6 fewer days of methadone treatment compared to the fixed-medication schedule group. In addition, the percentage of infants who were successfully treated using the symptom-triggered approach reached 100 percent by the end of the study period, and there were no adverse events resulting from this treatment approach.

"Our study showed that treating symptoms acutely with medication, and not having a fixed schedule with a long taper not only improves patient outcomes, but shortens their hospitalizations and decreases further exposure to opioid medications," said Elisha Wachman, MD, the study's corresponding author who is a neonatologist at BMC and an associate professor of pediatrics at Boston University School of Medicine. "This novel approach prioritizes the non-pharmacologic care approach for infants experiencing withdrawal symptoms and decreases the risk for unintended dependence that frequently occurs when infants are placed on prolonged methadone or morphine tapers."

Not only are they effective against Gram-positive and negative multi-resistant bacteria, they also appear not to trigger resistance when used to treat infection in mice. Such are the promises of the two new antibiotics created by Prof. Brice Felden and his team at the Inserm and Université de Rennes 1 'Bacterial Regulatory RNAs and Medicine' joint laboratory (U1230), in conjunction with a team from the Rennes Institute of Chemical Sciences (ISCR). This French advance could bring both fresh impetus and new possibilities for fighting antibiotic resistance worldwide. Details on this research will be published July 9 in PLOS Biology.

Antibiotics have saved so many lives over the previous century of their use in humans that they are considered to be one of the major breakthroughs of contemporary medicine. Unfortunately, growing resistance is gradually rendering them ineffective, with the threat of catastrophic public health consequences should this trend continue much longer. The few new antibiotics being brought to market essentially consist of so-called me-too drugs - meaning that they are derived from existing classes of antibiotics.

Researchers from Inserm and Université de Rennes recently identified a new bacterial toxin which they transformed into potent antibiotics active against various bacteria responsible for human infections, whether Gram-positive or negative. "It all started with a fundamental discovery made in 2011", explains Brice Felden, Director of the Bacterial Regulatory RNAs and Medicine laboratory in Rennes. "We realized that a toxin produced by Staphylococcus aureus whose role is to facilitate infection is also capable of killing other bacteria present in our body. What we had identified was a molecule with dual toxic and antibiotic properties. We thought that if we could separate these activities, we would be able to create a new antibiotic non-toxic to the body. A challenge that we accepted!"

In conjunction with the team of ISCR chemist Michèle Baudy Floc'h, a new family of so-called peptidomimetics was synthesized. As their name suggests, these peptides are inspired by the existing natural bacterial peptides but have been shortened and modified. Out of the twenty molecules created, two proved effective against resistant Staphylococcus aureus and Pseudomonas aeruginosa in mouse models of severe sepsis or skin infection. In addition, no toxicity to the other cells and organs, whether in animals or human cells was observed. These new compounds are well tolerated at their active doses - and even beyond - and are devoid of the renal toxicity issues often encountered with this type of compound. "We tested them at doses 10 to 50 times higher than the effective dose without seeing toxicity" specifies Felden, adding that "the participation and imagination of the team and our chemist colleagues was needed to devise the most active molecules possible."

Little resistance observed under experimental conditions

Important to note was that the bacteria that the researchers had left in contact for several days in the animals with these antibiotics showed no signs of resistance. In order to go further, the researchers created conditions favorable to the development of resistance in vitro and in vivo - with nothing happening. However, caution is still required here given the short experimental time periods (up to 15 days).

The antibacterial activity of these peptidomimetics is partially due to the capacity of its non-natural amino acids to reinforce the association of these compounds with the membranes of the infectious bacteria. This strong binding leads to membrane permeability and the death of the bacteria. "We think these new molecules represent promising candidates for the development of new antibiotics that can provide alternative treatments to antimicrobial resistance." The next step involves launching phase I clinical trials in humans. The patent has been licensed and a start-up created.

An aphrodisiac pheromone discovered in the semen of sea lampreys attracts ready-to-mate females, according to a study publishing July 9 in the open-access journal PLOS Biology by Anne M. Scott of Michigan State University, Zhe Zhang of Shanghai Ocean University, and colleagues.

In fish and other animals that use external fertilization, exposure to semen promotes spawning behaviors. However, no specific compounds in semen have been identified as aphrodisiac pheromones. In the new study, Richard Neubig, Weiming Li, and their colleagues sought to identify a pheromone from the milt (fish semen) of the sea lamprey (Petromyzon marinus) -- a jawless fish that spawns in aggregations where each spermiating male defends a nest, and ovulatory females move from nest to nest in order to mate. The researchers hypothesized that compounds in the milt may signal to ovulatory females the presence of spawning, spermiating males.

They found that an odorous compound called spermine, originally identified from human semen, is indeed a milt pheromone. At very low concentrations, spermine stimulated the lamprey olfactory system and attracted ovulatory females, but did not attract males or pre-ovulatory females. They identified the specific spermine-activated receptor in lamprey olfactory tissue, and a compound that blocks this receptor prevented the attraction of ovulatory females to spermine.

"We found the semen of sea lamprey contains spermine, a highly specific and potent pheromone, which attracts only ready-to-mate female sea lampreys," said Anne Scott. "This discovery implicates a new strategy that male animals use to recruit mates through the release of chemical cues in semen. Ovulatory females likely use spermine released along with sperm as a reliable signal for the presence of actively spawning males in the vicinity."

The results elucidate a mechanism whereby a pheromone in semen attracts ready-to-mate females and implicates a possible conservation of the olfactory detection of semen from jawless vertebrates to humans. According to the authors, their identification of milt pheromones may also have management implications for either the control or conservation of sea lamprey populations.