Worry about bond with second baby isn’t so common

Most mothers don’t worry excessively about bonding with a second baby or whether they’ll love each child equally, research finds.

The new study, however, uncovered some psychological risks among those moms who do worry.

The findings are contrary to a widely held belief that it is common and normal for women to be worried about loving their second baby as much as they currently love their first child. Although some mothers may worry a little if they can form an attachment to their second baby, such feelings are “not common and universal,” says Brenda Volling, psychology professor at the University of Michigan and the study’s lead author.

The study in the Infant Mental Health Journal focuses on 240 pregnant mothers expecting their second baby. About 70% of the mothers reported they did not worry at all about forming an attachment to their second baby—what the authors referred to as maternal-fetal relationship anxiety, or MFRA. On the other hand, about 20% worried a little, while 5% of the mothers worried “very much” or were “extremely” worried.

Volling, whose research focuses on early social and emotional development and parent-child interaction, says the women who experienced high levels of anxiety also had other psychosocial risks in their lives—including more depression, more conflict in their marriages, and their firstborn children had less secure attachments.

“These mothers also held more ambivalent and avoidant attachment styles themselves, based on their own childhood attachment experiences,” she says.

To overcome excessive anxiety and feelings of insecurity in close social relationships, mothers may wish to seek professional help from care providers or join support groups. Coming to understand the source of these insecurities “would most likely free them to feel closer to their babies,” Volling says.

The media also have a role in the perception of maternal mental health issues—sometimes negatively. In fact, Volling says blogs and articles about what moms can expect when having their second baby have made it difficult for mothers to seek help and support by claiming it was normal for mothers to feel less attached to their second babies.

“I was very concerned that we were doing a disservice to these women by telling them ‘not to worry,’ ‘it was completely normal,’ and ‘everything would change once the baby was born,’” she says.

Fathers’ attachment to their children is also important—and there are similarities to mothers’ attachment to the unborn baby.

“Fathers who are also depressed during the perinatal period can have difficulties establishing an attachment to the baby during pregnancy, and this does not appear to be because men themselves are not the pregnant parent,” Volling says.

As is the case for mothers, it is the social support and relationship risks surrounding these men that matter, she says.

The study’s coauthors are from the University of North Texas Health Science Center; Mathematica; and the Institute for Advanced Study in Toulouse.

Source: University of Michigan

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Judges still cite cases in which enslaved people are property

American judges still cite property cases of enslaved Black people as good law 160 years after the Emancipation Proclamation.

When Justin Simard was conducting research for his dissertation, he came across a case predating the Civil War related to slavery that was cited as precedent in 2012. He started looking for other slavery citations from the past 30 years, thinking he’d find one or two. Instead, he found more than 300.

“What I thought would be a footnote in my dissertation highlighting the odd decisions of a few judges turned into a broader examination of the legal profession’s treatment of slave cases,” says Simard, assistant professor of law at Michigan State University. “Not only are we ratifying their treatment as property in the past but also continuing to treat them as property in the present.”

Simard started the Citing Slavery Project to document the history and continued legacy of the law of slavery in the United States.

To date, Simard and his team of law students have found more than 7,000 cases involving enslaved people and have created a database of cases from the 20th and 21st centuries that continue to cite them as precedent.

“One of the most surprising things I’ve found is how extensively these cases are cited for so many different reasons,” Simard says. “There’s just so many areas of law—criminal law, property law, criminal procedure—all because in the 19th century, there were so many slave cases. And this is such an important formative era in making American law that just basic ground rules are established in that time. In just about any legal issue you can think of, cases of enslaved people are cited.”

Simard explains that the American legal system is a common law system, meaning that decisions made today are built on decisions of the past. So, when a judge or lawyer has a question, they look back to find comparable questions that have been answered in the past. When they find cases, judges “cite” a case as a way of presenting a similar example.

However, Simard says that in 80% of the cases his team identified, there’s no reference that the citations involve enslaved people.

“This was a tragic era in our country’s history, and if lawyers and judges today are continuing to cite slavery cases without acknowledging them as cases concerning enslaved people, they are papering over that era,” Simard says. “It’s a big blind spot. They want to treat these cases as ordinary law.”

Simard says citing slavery cases without acknowledging it “blurs the boundary between people and property.”

For example, a citation about damage to a car or damage to a dump truck that uses precedent about damage to an enslaved person dehumanizes the enslaved person—they’re all basically treated the same.

“Judges today must understand that many judges of the pre-Civil War era were slave owners themselves and made decisions within this context,” Simard says. “And, all of these cases were abrogated, at least in part, by the 13th Amendment, but judges fail to recognize the relevance of emancipation to their decisions.”

Simard and his research team of law students recently found that of all published legal cases throughout American history, 18% are what he calls “two-step” cases—those that cited a case that in turn cited a slavery case to support its argument. And beyond that, he estimates between 30% and 40% of all American legal cases are three-step cases. Simard’s article, “The Precedential Weight of Slavery,” will appear in the journal NYU Review of Law and Social Change.

Compelled to create awareness of enslaved citations, Simard’s team successfully lobbied the editors of “The Bluebook,” the legal profession’s citation bible, to change its rules in its 2021 edition, requiring cases involving enslaved people to be identified with the notation “(enslaved party)” or “(enslaved person at issue).”

“To stop citing these cases without acknowledgement is the first step, but to actually address the underlying issues is a much broader problem,” Simard says.

The legal profession must confront its role in slavery, Simard says.

“American slavery generated thousands of legal disputes,” he says. “Lawyers legitimized slavery by fitting cases involving enslaved people into standard legal categories. Even after emancipation, lawyers continued to treat slave cases as good law. And, today, American judges and lawyers continue to cite slave cases for fundamental legal propositions. It’s likely no coincidence that the legal system continues to create and enforce racial disparities.”

Simard says the law profession loves to pat itself on the back for the role it played in the civil rights movement, but what about the decades before that?

“The pervasive influence of the law of slavery on contemporary American law raises hard questions about what it means to acknowledge and redress the terrible damage that slavery inflicted,” Simard says. “It also raises questions about the law these decisions helped create. Scholars and judges have mostly avoided these questions by treating slave cases, especially those involving routine legal matters, as ordinary law.

“Slave cases are too deeply entwined in American law to completely excise their influence, but ignoring that influence should no longer be an option.”

Source: Michigan State University

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Transgenic ants glow in response to alarm pheromones

The world’s first transgenic ants have olfactory sensory neurons that flash green in response to odorants.

Ants navigate their richly aromatic world using an array of odor receptors and chemical signals called pheromones. Whether foraging or defending the nest, mating or tending to their young, ants both send and receive chemical signals throughout their lives. And the ant brain is well equipped to process the abundance of scents: The olfactory processing center in the ant’s brain has 10 times as many subdivisions as those of fruit flies, for example, even though their brains are about the same size.

And yet how the ant olfactory system encodes scent data has remained largely unknown.

Contrary to previous findings, the new study in Cell finds that only a few specific areas of the olfactory system lit up in response to alarm pheromones, danger signals that elicit panic and nest evacuation. The results raise questions about how sensory information is processed in the ant brain—as well as tantalizing possibilities for revealing what hundreds of other odorant receptors are up to.

“Neurogenetic tools have revolutionized the field of fruit fly neuroscience over the past decades, while social insect neuroscience has essentially been stuck,” says Daniel Kronauer, head of the Laboratory of Social Evolution and Behavior at Rockefeller University. “Our technical breakthroughs now finally allow us to apply these powerful tools in ants to study their social behavior.”

In the antennae

In 1958, E. O. Wilson reported that a secretion from the mandibular gland of harvester ants triggered their nestmates to quicken their pace and take up colony defense behaviors. He called this response “alarm behavior.” Since then, scientists have documented that alarm behavior and many other complex social activities in ant colonies are regulated by a vast array of pheromones.

Ants’ olfactory receptors are located on neurons in their antennae, which send their input to brain centers called the antennal lobes. The antennal lobes are comprised of specialized structures called glomeruli that are essential to scent processing. Some ants have more than 500 glomeruli—a bounty thought to be related to their heightened ability to perceive and discriminate between pheromones. Previous work from Kronauer’s lab has shown that ants whose odorant receptors have been knocked out cannot respond to pheromone signals.

In this study, the researchers created their transgenic subjects by injecting the eggs of clonal raider ants—a queenless species composed entirely of blind female workers—with genetic material encoding the synthetic protein GCaMP, which lights up neon green when calcium levels change during cellular activity.

“Our goal was to get GCaMP expressed only in a single cell type—the olfactory sensory neurons,” says lead author Taylor Hart, a researcher in Daniel Kronauer’s lab.

This was important because the antennal lobe is composed of multiple cell types: sensory neurons, projection neurons that carry sensory data to other parts of the brain, and lateral interneurons that link everything together. “Those other cell types can make signal-to-noise ratio poor, because they can be doing other activities, such as computations, processing information, and modulating signals,” Hart says. All of this can obscure what the olfactory neurons are doing.

The ant ‘panic button’

While successfully breeding a small group of ants with GCaMP expression in the olfactory sensory neurons, the team also developed a sophisticated two-photon calcium imaging technique that allowed them to record neural activity throughout the entire antennal lobes of live ants for the first time.

The researchers decided to focus on alarm pheromones, because they are particularly volatile and elicit strong and robust behavioral responses. They found that adult ants that detected the scents immediately scrambled to gather as many eggs in their mandibles as they could and then made a break for it, fleeing into an adjacent section of the test chamber.

Hart and her team then used their new techniques to monitor GCaMP fluorescence levels in the antennal lobes of 22 transgenic ants as they exposed them to a range of odors, including the alarm pheromones (which smell fruity to the human nose). The flashes clustered in six glomeruli in one region, suggesting that area may act as the brain’s panic button.

“We were expecting that a large portion of the antennal lobe would show some kind of response to these alarm pheromones,” Hart says. “Instead, we saw that the responses were extremely localized. Most of the antennal lobe did not respond at all.”

Hart says the findings reveal details about how the ant brain processes sensory input. Researchers have wondered whether the activity is privatized, with each glomerulus responding only to one or a few specific stimuli, or distributed, with unique combinations of glomeruli activated by a stimulus. A brain with more than 500 glomeruli that operated in a distributed way, with hundreds of sensors firing at once, would need extraordinary computational power when it comes to sensory processing, Hart says.

“Most of the odors we tested activated only a small proportion of the total glomeruli,” she says. “It seems that privatization is the way in the ant antennal lobe.”

Transgenic ant research to come

Considering that only six glomeruli responded out of 500, Hart wonders, “What do they need all these different glomeruli for? The fruit fly gets by with just 50.”

It will now be easier to find out why ants have a greater need to differentiate odor stimuli than other insects, Kronauer says—and not only because Hart has since bred hundreds of transgenic ants who differ from their wild counterparts only in their ability to signal in fluorescence, providing a robust pool for future research.

“The tools that Taylor developed open up a really big range of questions that were inaccessible to us until now,” he says. These include associating specific glomeruli with the variety of pheromones ants use for things like raiding, recruitment, and distinguishing between nestmates and outsiders. “There are also interesting developmental questions about how the ant olfactory system gets assembled, because it’s so complex. Larvae also have olfactory sensory neurons, so now we can look at their sensory capabilities.”

Source: Rockefeller University

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U.N. opens “window of opportunity” to improve space governance

NEW YORK — A United Nations official says there is an opportunity over the next 15 months to improve how nations manage space activities to address emerging issues ranging from orbital debris to space resources.

Speaking at the Secure World Foundation’s Summit for Space Sustainability here June 13, Guy Ryder, U.N. undersecretary-general for policy, said the organization was making efforts to address space diplomacy ahead of a September 2024 U.N. conference called Summit of the Future that will address broad challenges the world is facing.

“We have a window of opportunity over the next 15 months,” he said, “where we can accelerate space diplomacy and advance the governance issue.”

The U.N. released a policy paper in May on outer space governance, outlining several issues it wants to address. Among them are coordination issues for a rapidly growing population of space objects in general in Earth orbit, and more specifically increasing amounts of debris.

“The most obvious and perhaps the most extraordinary change in recent years has been the sheer number of objects being launched into space,” Ryder said. “The fact that more objects have been launched in the last 10 years than in the previous 50 years combined offers, I think, boundless development opportunities and governance needs.”

Those governance needs revolve around space traffic coordination, with limited progress to address that on a global scale. That puts the safety and sustainability of space at risk, he argued, which is exacerbated by the growth of debris, particularly from anti-satellite tests. Efforts to remove debris show promise, but he said that without international norms regarding such activities, “the use of these technologies can be a source both of tension and of conflict.”

Other issues of concern revolve around the human exploration of the moon and utilization of space resources. He noted that while the Committee on the Peaceful Uses of Outer Space (COPUOS) has been examining space resource utilization, there is no agreement yet on how countries and companies can use those resources.

Ryder offered no specific proposals to address those issues, but said meetings by COPUOS and other organizations over the next 15 months offered opportunities to develop proposals to address them ahead of the Summit of the Future, where space will be one of many agenda items.

The goal, he said, is to develop a single unified governance framework that covers space traffic coordination, debris and resource management, as well as norms and rules to avoid armed conflict in outer space. However, he said the U.N. would be open to separate frameworks for each issue “if that path looks likelier to achieve results.”

Ryder said efforts to develop governance mechanisms on the high seas, such as the U.N. Convention on the Law of Sea, offered a model for space. “All of this provides us with the confidence that the kinds of agreements concluded in the past are possible in the future, even in today’s admittedly challenging geopolitical climate.”

Part of the coordination efforts leading up to the Summit of the Future will be a conference hosted by Portugal in the spring of 2024. That is intended to help develop proposals to be presented at the summit, said Hugo André Costa, member of the executive board of the Portuguese Space Agency, during another conference panel.

There will be two virtual workshops ahead of the Portuguese conference, one in October on technology issues and a second in March 2024 on policy issues, to solicit ideas from governments, industry and academia. “This is the only way that we can prepare for the future,” he argued.

There have been discussions about whether COPUOS, with more than 100 member nations operating on a consensus model where all nations need to agree, is suited for the current space environment. “It’s slow, it’s frustrating but ultimately it’s a slow, steady process,” said Valda Vikmanis Keller, director of the U.S. State Department’s Office of Space Affairs, saying the open discussions there remain essential. “It’s the only way forward.”

“We need to continue work that is being done in COPUOS,” said Costa, including “difficult discussions” on these issues. “It’s through the difficult conversations and the difficult discussions that we’re going to have that we can support the work of COPUOS and move forward.”

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Animal movement powers new GPS wildlife tracker

A new battery-free GPS wildlife tracker runs on kinetic energy, the energy generated when the animal moves.

The wolf’s comeback in Europe has preoccupied people all across the continent over the last years. Where is it? What is its range? What does it live on? The only way to get solid answers to these questions is through GPS tracking.

In December, it was a cause for celebration when a GPS collar was fitted onto a wolf for the first time in Denmark. Only three months later, the signal stopped.

GPS trackers that stop working or run out of power prematurely are a frequent problem and source of frustration among researchers who want to track mammals for longer periods, says biologist and postdoc Rasmus W. Havmøller of the University of Copenhagen. Typically, batteries are the problem.

“When studying wildlife with GPS technology, the biggest limitation is always going to be the battery. It’s enormously frustrating. It is not uncommon that one gets to track an animal for a few months at most before the GPS device goes dead. But tracking an animal for a longer period of time is often important, as in the case with wolves here in Denmark. Therefore, we need a more reliable power source,” Havmøller says.

“Solar cells work fine for birds, but solar cells are so fragile that mammals tend to crush them. Moreover, many mammals are nocturnal. So we needed to come up with an alternative. I had long thought about the cleverness of the automatic wristwatches that many of us wear, which harvest energy from our own body’s movements,” Havmøller says.

“It sure as heck works! The more an animal moves, the more energy it generates and the more GPS location messages it sends. Unless the equipment itself breaks, it will work throughout an animal’s lifetime,” says Havmøller. “At the same time, it only weighs 150 grams (about 0.3 pounds)—significantly less than most other GPS trackers—so it can even be fitted onto small mammals.”

Further, the wildlife tracker device costs less than a tenth of traditional GPS collars, which run up to €3,500-4,000 (about $3,700) apiece.

Havmøller and his colleague, lead author Troels Gregersen, are assembling the GPS trackers themselves in a small laboratory at the Natural History Museum of Denmark.

The device, dubbed “KineFox” has been fitted onto one of the Danish Nature Agency’s wild horses and has been sending data on the horse’s position for the past six months. The tracker has also been tested on dogs and a bison. The plan is for it to be long-term tested on several animal species.

Rewilding is one area that the researchers envision the GPS tracker making a difference. The lack of supervision of animals released into the wild is a problem that has given rise to heated debate in recent years.

“The systematic human supervision of wild horses and cattle, to keep them from starving for example, is extremely resource intensive. Our tracker is ready to address this task,” Havmøller says.

Because the tracking unit contains an accelerometer that measures how an animal moves, wildlife managers can get a glimpse of an animal’s condition through its activity pattern.

“Studies with cows and pigs show that they begin moving differently when ill. In this way, it is likely that the tracker will also be able to tell something about an animal’s health. This means that you can comply with supervision legislation without having to get people out there every single day to find and inspect animals,” he says.

Havmøller points out that Kinefox can also lend a hand to endangered species, wherever knowledge about the way they live and move about is lacking.

“There is no good alternative to this GPS device when it comes to serious long-term studies and studies of how animal species disperse. Because either the equipment is too big, too heavy, or too fragile. But it’s really important to understand how a species moves from one place to another, and where they are shot or poisoned, for example—not least if we want to protect them better.”

Havmøller has been frustrated by GPS devices whose batteries died suddenly while studying both endangered leopards and wild dogs.

“There are endangered species where we know incredibly little about what they do for most of their lives. These include tigers, which can travel thousands of kilometers, as well the Asiatic wild dogs and leopards that I’m involved with.

“When wild dogs reach sexual maturity, leave their mother, and set out on their own, they are very vulnerable. But from that moment on, we know nothing about what they’re up to and why some die while others make it. It is a black box. I hope that this invention can remedy that,” he says.

Havmøller and his research colleagues are now in contact with several potential stakeholders about the long-term testing of Kinefox on various animal species.

The research on the tracker appears in PLOS ONE.

Additional coauthors are from the Max Planck Institute of Animal Behavior, DTU Engineering Design and Product Development, and the University of Copenhagen.

Source: University of Copenhagen

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Fewer than three meals a day may lower type 2 diabetes risk

Time-restricted eating may reduce the risk of developing type 2 diabetes and improve overall health, according to a new review.

This type of fasting means having regular but fewer meals, cutting out late-night snacks, and not eating for 12 to 14 hours (often overnight).

After a comprehensive review of published, peer-reviewed studies, the researchers found a connection between number of meals and obesity and type 2 diabetes.

“What we’ve been taught for many decades is that we should eat three meals a day plus snacking in between,” says Krzysztof Czaja, an associate professor of biomedical sciences in the University of Georgia’s College of Veterinary Medicine. “Unfortunately, this appears to be one of the causes of obesity.”

The three meals and snacks style of eating prevents insulin levels from going down during the day, and, with the amount of calories and sugars Americans consume on average, that can overload the body’s insulin receptors. That leads to insulin resistance and often type 2 diabetes.

“That’s why it’s so hard to lose body fat,” Czaja says. “We are not giving our bodies a chance to use it. Having fewer meals a day will allow these fat deposits to be used as an energy source rather than the sugar we keep consuming.”

The researchers found that time-restricted eating allows the body to relax and lower insulin and glucose levels, which in turn can improve insulin resistance, brain health, and glycemic control. It can also reduce calorie intake by around 550 calories per day without the stress of calorie counting.

Previous studies have shown disruptions to sleep and meal schedules can change both the type and amount of bacteria and other microorganisms in the digestive tract. But fasting may positively alter the gut microbiome, potentially staving off inflammation and a variety of metabolic disorders.

Additionally, the review suggests time-restricted eating can help regulate hormones responsible for appetite regulation and energy levels.

Regular meal schedules, eating breakfast, and decreasing meals and snacks can help guard against obesity and type 2 diabetes, according to the study. And not all breakfasts are created equal. Aim for healthy fats and protein, like eggs, and avoid the sugar-filled breakfast cereals and pastries.

Although time-restricted eating appears to improve health, the researchers found that other types of restricted eating, such as fasting for days on end, provides few benefits.

More than four in 10 Americans are clinically obese, meaning their weight is higher than what is considered a healthy range for their height. Almost 10% are severely obese, according to the Centers for Disease Control and Prevention.

Obesity may lead to a variety of health conditions, including type 2 diabetes, heart disease, and even some cancers.

“Obesity is an epidemic right now, especially in the United States,” Czaja says. “It is a preventable disease. When we started looking at the research, we found that ancient humans didn’t eat every day. That means our body evolved not needing food every day.”

The modern approach of three meals plus snacks became popular decades ago, and it’s a hard pattern to break.

The researchers caution that eating is not a one size fits all situation. Smaller, less active people need fewer calories on average than taller athletes, for example. So for some, one meal of nutrient-rich food might be another while others may need more.

But one thing was very clear from the literature: Fewer meals of high-quality food is a good guideline for individuals at risk of developing type 2 diabetes and obesity.

“Also definitely avoid late-night eating,” Czaja says. “Our midnight snacks spike insulin, so instead of us going into a resting state when we sleep, our GI is working on digestion. That’s why we wake up in the morning tired—because we don’t get enough resting sleep.”

Source: University of Georgia

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‘Vaginal seeding’ restores healthy bacteria for C-section babies

Newborns delivered by cesarean section who are swabbed with the vaginal fluid of their mothers after birth, a process called vaginal seeding, have beneficial bacteria restored to their skin and stools, researchers report.

In the first randomized study of its kind, researchers found vaginal seeding definitively engrafted new strains of maternal bacteria in the babies’ bodies. These strains normally wouldn’t be present in the newborns because, during C-sections, infants are directly extracted from their mothers’ wombs, bypassing the vaginal canal.

“Our study is the first double-blind, randomized, placebo-controlled trial to determine whether vaginal seeding causes maternal bacteria to engraft in the skin and stool of neonates,” says Maria Gloria Dominguez-Bello, professor of microbiome and health it the biochemistry and microbiology department at the Rutgers University School of Environmental and Biological Sciences and an author of the study published in mBio.

Neonates are infants who are younger than 28 days old. In the randomized, blinded study, neither the participants nor the study’s facilitators knew which of the subjects received the material being studied—in this case, the participating mothers’ vaginal fluids—and who was given a placebo.

“Despite some limitations in this early study, including a small sample size and only two samples taken over time, we observed significant effects of vaginal seeding on the neonatal microbiota,” Dominguez-Bello says.

The term microbiome refers to the collection of genomes or essential genetic material from all the microorganisms in the environment. The word microbiota usually pertains to microorganisms—bacteria, viruses, and fungi—found within a specific environment, such as on the skin or in the gut. Scientists have found over recent decades that these collections of microorganisms play a pivotal role in human health, interacting with metabolism, the immune system and the central nervous system.

Numerous studies have shown substantial differences exist between the microbiomes in neonates delivered by C-section and those born in a vaginal delivery. Some scientists, such as Dominguez-Bello, theorize that babies born via C-section may miss out on the exposure to the first live microbes meant to colonize their bodies and sustain their health.

An increasing body of research demonstrates that this thwarting of microbial colonization during critical early-life windows of development alters metabolic and immune programming and is associated with an increased risk of immune and metabolic diseases—including asthma, food allergies, obesity, and diabetes.

In the study, the scientists took samples of microbiota from the skin and stool of 20 infants during two periods—when the babies were one day old and when they were one month old. They found evidence the maternal microbes had been engrafted in the infants. They also found that, when compared with the babies that received a placebo, the infants that received vaginal seeding hosted a different bacterial population on their skin and in their stool. Their microbiomes included a pattern of bacterial diversity that was more characteristic of those babies who have been breastfed and have been delivered vaginally.

As part of a continuing study, the researchers will assess the microbiomes of the babies for the next five years, as well as tracking their growth patterns and whether they develop any markers of metabolic or immune-related disease.

The scientists also are continuing the study to increase the number of babies and to assess infant health outcomes.

“There is now a critical need to evaluate the health benefits and safety of vaginal seeding in large randomized controlled trials,” Dominguez-Bello says.

Additional coauthors are from Johns Hopkins University; the National Institute of Allergy and Infectious Diseases; Inova Children’s Hospital and Inova Women’s Hospital in Falls Church, Virginia; and Rutgers.

The National Institute of Allergy and Infectious Diseases’ Intramural Research Program and a grant from the NIH National Heart, Lung and Blood Institute funded the work.

Source: Rutgers University

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World Economic Forum offers new debris mitigation guidelines

NEW YORK — The World Economic Forum (WEF) has released a new set of guidelines intended to reduce the creation of orbital debris with the support of some, but not all, major satellite operators.

The Space Industry Debris Mitigation Recommendations document, released by the WEF June 13, outlines recommendations to avoid collisions that can create debris by limiting the lifetime of satellites in orbit after they have completed their missions and improving coordination among satellite operators.

Among those recommendations is to establish a success rate for “post-mission disposal,” or removal of satellites from orbit after the end of their missions, to 95% to 99%. That disposal should be completed no more than five years after the end of each satellite’s mission.

Current international guidelines, often incorporated into national law, set a post-mission disposal timeline of up to 25 years, although the U.S. Federal Communications Commission adopted a new rule last September that will reduce it to five years for satellites that are licensed or obtain market access from the agency. Even with the 25-year guideline, compliance has been below 50% by some metrics.

“We wanted to push the envelope a little bit on some of these concrete, specific targets,” said Nikolai Khlystov, lead for the WEF’s Future of Space initiative, during a panel at the Secure World Foundation’s Summit for Space Sustainability here June 13. It was intended, he said, to build on past work by the WEF, notably the development of the Space Sustainability Rating that assesses how satellite systems meet best practices for safe and sustainable space operations.

Other recommendations in the document call for satellites to be maneuverable, preferably though onboard propulsion, when operating at altitudes above 375 kilometers. Satellite operators should answer “all reasonable and legitimate requests” for space traffic coordination from other operators and share orbital data.

The document calls on governments to adopt the new post-mission disposal guidelines and mandate the use of active debris removal systems for space objects that cannot comply with them, once such systems are “practical and commercially affordable.” It also recommends increased investments in space situational awareness capabilities and encourages sharing of data on orbits of space objects.

The audience for the document, Khlystov said, is as much stakeholders outside the industry as it is satellite operators. “You can take this document to policymakers, investors and other stakeholders and say this is where a significant part of the industry is at.”

Twenty-seven companies endorsed the document at the time of its release. They include companies that operate large satellite constellations, such as OneWeb, Planet and Spire, as well as a mix of other established and emerging space companies.

Among them is GHGSat, a Canadian company that has nine smallsats in orbit to monitor greenhouse gas emissions. “Even before engaging in this discussion, we needed to come up with new practices” on space sustainability, said Bryn Orth-Lashley, technical operations and service delivery manager at GHGSat, during the panel. “It wasn’t that much of an uphill climb.”

He noted the company’s satellites do not have onboard propulsion but are able to maneuver by alternative means, such as differential drag, to comply with the guidelines. The company will continue to operate satellites after the end of their commercial missions, including performing avoidance maneuvers, until reentry.

Some major companies, though, have not signed on. They include SpaceX, which operates by far the largest satellite constellation with its Starlink system, and Amazon, which is developing its Project Kuiper constellation. Even some satellite operators that have espoused the importance of space sustainability, like Viasat, are not included.

Khlystov said the WEF undertook a “pretty comprehensive effort” to engage with as many satellite operators as possible. “If some actors didn’t sign on, I don’t think it’s a sign that they are against these standards,” he said, noting there was some “pretty significant input” from operators not included among the 27 signatories.

“I was very encouraged by the process,” he continued. “We had very good discussions. Not everybody who was part of the discussions came on board, but they were all very engaged.”

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Salt on Itokawa asteroid suggests liquid water

The discovery of tiny salt grains in an asteroid sample provides strong evidence that liquid water may be more common in the solar system’s largest asteroid population than previously thought.

The smattering of tiny salt crystals discovered in a sample from an asteroid has researchers excited, because these crystals can only have formed in the presence of liquid water.

Even more intriguing, according to the research team, is the fact that the sample comes from an S-type asteroid, a category known to mostly lack hydrated, or water-bearing, minerals. The discovery strongly suggests that a large population of asteroids hurtling through the solar system may not be as dry as previously thought. The finding, published in Nature Astronomy, gives renewed push to the hypothesis that most, if not all, water on Earth may have arrived by way of asteroids during the planet’s tumultuous infancy.

“Once these ingredients come together to form asteroids, there is a potential for liquid water to form.”

Tom Zega, the study’s senior author and a professor of planetary sciences at the the University of Arizona Lunar and Planetary Laboratory, and Shaofan Che, lead study author and a postdoctoral fellow at the Lunar and Planetary Laboratory, performed a detailed analysis of samples collected from asteroid Itokawa in 2005 by the Japanese Hayabusa mission and brought to Earth in 2010.

The study is the first to prove that the salt crystals originated on the asteroid’s parent body, ruling out any possibility they might have formed as a consequence of contamination after the sample reached Earth, a question that had plagued previous studies that found sodium chloride in meteorites of a similar origin.

“The grains look exactly like what you would see if you took table salt at home and placed it under an electron microscope,” Zega says. “They’re these nice, square crystals. It was funny, too, because we had many spirited group meeting conversations about them, because it was just so unreal.”

Zega says the samples represent a type of extraterrestrial rock known as an ordinary chondrite. Derived from so-called S-type asteroids such as Itokawa, this type makes up about 87% of meteorites collected on Earth. Very few of them have been found to contain water-bearing minerals.

“It has long been thought that ordinary chondrites are an unlikely source of water on Earth,” says Zega who is the director of the Lunar and Planetary Laboratory’s Kuiper Materials Imaging & Characterization Facility. “Our discovery of sodium chloride tells us this asteroid population could harbor much more water than we thought.”

Today, scientists largely agree that Earth, along with other rocky planets such as Venus and Mars, formed in the inner region of the roiling, swirling cloud of gas and dust around the young sun, known as the solar nebula, where temperatures were very high—too high for water vapor to condense from the gas, according to Che.

“In other words, the water here on Earth had to be delivered from the outer reaches of the solar nebula, where temperatures were much colder and allowed water to exist, most likely in the form of ice,” Che says. “The most likely scenario is that comets or another type of asteroid known as C-type asteroids, which resided farther out in the solar nebula, migrated inward and delivered their watery cargo by impacting the young Earth.”

The discovery that water could have been present in ordinary chondrites, and therefore been sourced from much closer to the sun than their “wetter” kin, has implications for any scenario attempting to explain the delivery of water to the early Earth.

The sample used in the study is a tiny dust particle spanning about 150 micrometers, or roughly twice the diameter of a human hair, from which the team cut a small section about 5 microns wide—just large enough to cover a single yeast cell—for the analysis.

Using a variety of techniques, Che was able to rule out that the sodium chloride was the result of contamination from sources such as human sweat, the sample preparation process, or exposure to laboratory moisture.

Because the sample had been stored for five years, the team took before and after photos and compared them. The photos showed that the distribution of sodium chloride grains inside the sample had not changed, ruling out the possibility that any of the grains were deposited into the sample during that time. In addition, Che performed a control experiment by treating a set of terrestrial rock samples the same as the Itokawa sample and examining them with an electron microscope.

“The terrestrial samples did not contain any sodium chloride, so that convinced us the salt in our sample is native to the asteroid Itokawa,” he says. “We ruled out every possible source of contamination.”

Zega says tons of extraterrestrial matter is raining down on Earth every day, but most of it burns up in the atmosphere and never makes it to the surface.

“You need a large enough rock to survive entry and deliver that water,” he says.

Previous work led by the late Michael Drake, a former director of the Lunar and Planetary Lab, in the 1990s proposed a mechanism by which water molecules in the early solar system could become trapped in asteroid minerals and even survive an impact on Earth.

“Those studies suggest several oceans worth of water could be delivered just by this mechanism,” Zega says. “If it now turns out that the most common asteroids may be much ‘wetter’ than we thought, that will make the water delivery hypothesis by asteroids even more plausible.”

Itokawa is a peanut-shaped near-Earth asteroid about 2,000 feet long and 750 feet in diameter and is believed to have broken off from a much larger parent body. According to Che and Zega, it is conceivable that frozen water and frozen hydrogen chloride could have accumulated there, and that naturally occurring decay of radioactive elements and frequent bombardment by meteorites during the solar system’s early days could have provided enough heat to sustain hydrothermal processes involving liquid water. Ultimately, the parent body would have succumbed to the pummeling and broken up into smaller fragments, leading to the formation of Itokawa.

“Once these ingredients come together to form asteroids, there is a potential for liquid water to form,” Zega says. “And once you have liquids form, you can think of them as occupying cavities in the asteroid, and potentially do water chemistry.”

The evidence pointing at the salt crystals in the Itokawa sample as being there since the beginning of the solar system does not end here, however. The researchers found a vein of plagioclase, a sodium-rich silicate mineral, running through the sample, enriched with sodium chloride.

“When we see such alteration veins in terrestrial samples, we know they formed by aqueous alteration, which means it must involve water,” Che says. “The fact that we see that texture associated with sodium and chlorine is another strong piece of evidence that this happened on the asteroid as water was coursing through this sodium-bearing silicate.”

Source: University of Arizona

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Most people with heart disease don’t use health trackers

Fewer than 1 in 4 people with or at risk for heart disease use wearable health trackers, and only half of those who wear them do so consistently.

Wearable devices, such as those made by Apple and Fitbit, are becoming increasingly sophisticated in their ability to track heart rates, physical activity, and sleep, and obtain electrocardiograms, and several other measures—capabilities that can be especially helpful for monitoring the health of people with cardiovascular disease (CVD).

The population-based, nationally representative study, published in JAMA Network Open, included 9,303 participants from the Health Information National Trends Survey (HINTS). Eighteen percent of people with established CVD and 26% at risk for CVD reported using wearable devices compared with 29% of the general population.

“We are so used to seeing data that lives in the health care setting, but increasingly people in the community have access to these devices and technologies that can provide a very well-rounded set of data points that can inform their clinical care,” says senior author Rohan Khera, assistant professor at Yale School of Medicine, and director of the Cardiovascular Data Science (CarDS) Lab.

“We wondered if we looked at a national survey of individuals, could we figure out who are the people who are actually using these devices? And if we looked at a specific population, those with cardiovascular diseases, what are we seeing?”

Older age, lower educational attainment, and lower household income were associated with significantly lower odds of wearable device use, likely due to these populations having less access to these devices or discomfort with using the technology.

“The people who stand to benefit the most tend to use them the least,” says Khera. “I think part of it is awareness. People may not recognize the potential value that these devices can bring to the health side, especially since the evidence for their value to health is still evolving.

“And the other piece is of course their cost and the fact that people who have health disorders might have actually other costs to take care of, so these things may seem frivolous for them.”

Identifying the obstacles among people who could benefit from wearable devices but aren’t using them ultimately led the researchers to consider whether strategies should be put in place to ensure equitable adoption.

“If we are increasingly recognizing the health worth of these devices,” says Khera, “should we start having a societal debate about whether it remains a concierge technology only for the wealthy? Or do we start thinking about it as a medical intervention and therefore under the purview of insurance coverage and so forth?”

Source: Christina Frank for Yale University

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