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Astronomers determine the age of three mysterious baby stars at the heart of the Milky Way

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Astronomers determine the age of three mysterious baby stars at the heart of the Milky Way


Through analysis of high-resolution data from a ten-metre telescope in Hawaii, researchers at Lund University in Sweden have succeeded in generating new knowledge about three stars at the very heart of the Milky Way. The stars proved to be unusually young with a puzzling chemical composition that surprised the researchers.

The study, which has been published in The Astrophysical Journal Letters, examined a group of stars located in the nuclear star cluster that makes up the heart of the galaxy. It concerns three stars that are difficult to study because they are extremely far away from our solar system, and hidden behind enormous clouds of dust and gas that block out light. The fact that the area is also full of stars makes it very complicated to discern individual stars.

In a previous study, the researchers put forward a hypothesis that these specific stars in the middle of the Milky Way could be unusually young.

“We can now confirm this. In our study we have been able to date three of these stars as relatively young, at least as far as astronomers are concerned, with ages of 100 million to about 1 billion years. This can be compared with the sun, which is 4.6 billion years old,” says Rebecca Forsberg, researcher in astronomy at Lund University.

The nuclear star cluster has mainly been seen, quite rightly, as a very ancient part of the galaxy. But the researchers’ new discovery of such young stars indicates that there is also active star formation going on in this ancient component of the Milky Way. However, dating stars 25,000 light years from Earth is not something that can be done in a hurry.

The researchers used high-resolution data from the Keck II telescope in Hawaii, one of the world’s largest telescopes with a mirror ten metres in diameter. For further verification, they then measured how much of the heavy element, iron, the stars contained. The element is important for tracing the galaxy’s development, as the theories the astronomers have about how stars are formed and galaxies develop indicate that young stars have more of the heavy elements, as heavy elements are formed to an increasing extent over time in the universe.

To determine the level of iron, the astronomers observed the stars’ spectra in infrared light which, compared with optical light, are parts of the light spectrum that can more easily shine through the densely dust-laden parts of the Milky Way. It was shown that the iron levels varied considerably, which surprised the researchers.

“The very wide spread of iron levels could indicate that the innermost parts of the galaxy are incredibly inhomogeneous, i.e. unmixed. This is something we had not expected and not only says something about how the centre of the galaxy appears, but also how the early universe may have looked,” says Brian Thorsbro, researcher in astronomy at Lund University.

The study sheds significant light on our understanding of the early universe and the functioning of the very centre of the Milky Way. The results may also be of benefit to inspire continued and future explorations of the heart of the galaxy, as well as the further development of models and simulations of the formation of galaxies and stars.

“Personally, I think it is very exciting that we can now study the very centre of our galaxy with such a high level of detail. These types of measurements have been standard for observations of the galactic disc where we are located, but have beenunreachable goal for more faraway and exotic parts of the galaxy. We can learn a lot about how our home galaxy was formed and developed from such studies,” concludes Rebecca Forsberg.

In addition to Lund University, the following organisations and higher education institutions participated in the study: Observatoire de la Côte d’Azur, the University of Tokyo, Observatoire de Paris, the University of California Los Angeles, and Miyagi University of Education.



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Bedtime battles: 1 in 4 parents say their child can’t go to sleep because they’re worried or anxious

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Bedtime battles: 1 in 4 parents say their child can’t go to sleep because they’re worried or anxious


Many bedtime battles stem from children’s after dark worries, suggests a new national poll.

And while most families have bedtime rituals to help their little ones ease into nighttime, many rely on strategies that may increase sleep challenges long term, according to the University of Michigan Health C.S. Mott Children’s Hospital National Poll on Children’s Health.

Overall, one in four parents describe getting their young child to bed as difficult — and these parents are less likely to have a bedtime routine, more likely to leave on a video or TV show, and more likely to stay with their child until they’re asleep.

“Our report reinforces the common struggle of getting young children to sleep. When this transition to bedtime becomes a nightly conflict, some parents may fall into habits that work in the moment but could set them up for more sleep issues down the road,” said Mott Poll co-director Sarah Clark, M.P.H.

“Establishing a consistent bedtime routine is crucial. When children don’t get enough rest, it can impact their physical development, emotional regulation and behavior.”

Nearly one in five parents say they have given their kids melatonin to help with sleep while a third stay in the room until their child completely dozes off, according to the nationally representative poll that includes responses from 781 parents of children ages one to six surveyed in February.

Nighttime worries interfere with sleep

Parents share common reasons behind bedtime struggles, with nearly a quarter saying their child’s sleep is often or occasionally delayed due to being worried or anxious.

A particular challenge, parents say, is when children don’t stay asleep. More than a third of parents say their child wakes up upset or crying, with more than 40% saying their child moves to their parents’ bed and about 30% saying children insist that the parent sleep in their room.

“Many young children go through stages when they become scared of the dark or worry that something bad might happen, causing them to delay bedtime or become distressed by parents leaving the room. Bad dreams or being awakened in the middle of the night can also disrupt sleep,” Clark said.

“Although this is a normal part of a child’s development, it can be frustrating when parents already feel tired themselves at the end of the day. Parents should find a balance between offering reassurance and comfort while maintaining some boundaries that help ensure everyone — both kids and adults — get adequate sleep.”

More findings from the report, plus Clark’s recommendations for helping young children fall and stay asleep:

Stick to a regular bedtime routine

Most parents polled report having a bedtime routine for their child, often including brushing teeth, reading bedtime stories and/or bathing. Less than half also say their child has a drink of water or snack, turns off devices, prays and talks about their day.

Other bedtime habits include holding a blanket or stuff animal or sucking a pacifier or fingers.

Not only does having a consistent bedtime routine help make the nighttime transition smoother, Clark says, it also provides one-on-one time, allowing the child to get their parent’s full attention.

“A predictable bedtime routine provides a sense of security and comfort and signals to the child that it’s time to slow down,” she said.

“Knowing what to expect next can reduce anxiety and help children feel safe and relaxed. Having this dedicated time with parents also promotes bonding and emotional connection, creating positive associations with bedtime.”

Nearly two-thirds of parents also said children staying up to play was a major factor in delaying sleep. Clark says, highlighting the need to wind down at least an hour before bed.

Promote an environment conducive to sleep

A little less than half of parents polled say their child sleeps in their own bedroom while less than a quarter share a bedroom with siblings or in the parents’ bedroom. One in 10 kids spend part the night in their own bedroom and part of the night with parents.

More than two-fifths of parents polled said noise from other rooms interfered with their child’s sleep.

“The sleep environment can have a major effect on a child’s sleep quality, including getting to sleep and staying asleep through the night,” Clark said.

“When possible, children should have their own bed in a room that is quiet, without a lot of noise from other family members.”

Many parents polled also use a nightlight or crack the bedroom door so the child isn’t in complete darkness, Clark says, but parents should make sure the light does not shine directly at the child’s face.

Some parents also play calming music or stories to help their child go to sleep, while others use a white noise machine or app. However, Clark cautions to keep white noise machines at no more than 50 decibels and placed at least seven feet from the child’s bed to prevent unintended damage to the child’s hearing.

Talk to a doctor before using aids like melatonin

Many types of melatonin products are advertised as being appropriate for children but these products have not undergone rigorous testing for safety and effectiveness, and their side effects and long term impact on a child’s growth and development are unknown, Clark says.

“Although melatonin is a natural hormone that regulates sleep-wake cycles and may be fine to use occasionally, parents shouldn’t rely on it as a primary sleep aid,” Clark said.

“Parents who are considering giving melatonin to their young child should consult with their pediatrician to discuss options and rule out other causes of sleep problems first.”

If using melatonin, parents should also start with the lowest dose possible.

In addition, it’s important to keep electronics such as tablets or televisions out of children’s bedroom, as the blue light emitted by many of these screens interferes with the natural production of melatonin.

Offer comfort but enforce boundaries

Parents can help ease little ones’ anxiety by allowing extra time to let them talk about their day, which might draw out specific worries and give parents a chance to provide compassion and reassurance, Clark said.

Rather than remaining in the room, parents can also offer to check on the child every few minutes, which acknowledges the child’s fears and offers a reassuring presence, but still maintains a calm sleep environment and promotes sleep independence.

“Families can incorporate comforting rituals to help transform nighttime fears into a calming experience,” Clark said.

Have a consistent approach when children wake up in the night

Some children are prone to vivid dreams or nightmares and may have difficulty getting back to sleep. Parents should decide on their approach to this situation and stick with it, Clark says, whether it’s taking the child back to bed or allowing them to stay in the parents’ room.

“Being consistent in carrying out that approach will help the child adjust and be more likely to return to sleep,” Clark said.

Ease into changes in sleep patterns, such as dropping naps

For young children, a major sleep-related transition is discontinuing daytime naps. In general, children ages one to two should get 11-14 hours of sleep with naps while the amount of recommended sleep decreases slightly from ages three to six.

If children are taking longer to fall asleep at nap time, resisting naps or suddenly having difficulty falling asleep at night or waking up earlier than usual in the morning, it may be time to drop the nap, Clark says.

“Parents may need to adjust sleep routines gradually to transition to changes to a child’s sleep patterns,” Clark said.

Other changes that can affect a child’s sleep include transitioning from a crib to a toddler bed, starting school, having a change in their daytime routine, or being outdoors for longer than usual.



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Direct evidence found for dairy consumption in the Pyrenees in the earliest stages of the Neolithic

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Direct evidence found for dairy consumption in the Pyrenees in the earliest stages of the Neolithic


A joint study conducted by the Universitat Autònoma de Barcelona, the University of Zaragoza and the University of Strasbourg on the remains of the Chaves and Puyascada caves, both located in the province of Huesca, Spain, yields the first direct proof of the consumption and processing of dairy products in the Pyrenees already at the start of the Neolithic period, approximately 7,500 years ago, as well as the consumption of pig. The results lead to doubts about the belief that these products were first used much later in the Pyrenean mountain range.

The analysis of the content and use of prehistoric vessels has become a valuable source of information on the food patterns and subsistence practices of past societies. A research conducted on the materials found at the Huescan sites of Cueva de Chaves (Bastaràs), at 640 metres above sea level, and at Espluga de la Puyascada (La Fueva), at 1,300 metres above sea level, in a strictly Pyrenean mountain region, now has yielded the first direct evidence of dairy product consumption and processing in the Pyrenees during the earliest stages of the Neolithic.

The study was conducted by prehistorians from the Universitat Autònoma de Barcelona (UAB) and the University of Zaragoza, and chemists from the University of Strasbourg, France, on materials on display at the Huesca Museum. The findings have now been published in the journal Archaeological and Anthropological Sciences.

The research was conducted through a combination of techniques used to identify organic residues and the isotopic characterisation of fatty acids to determine animal origin, as well as data obtained of the morphology and functionality of ceramics and the archaeozoological studies of both sites.

The analysis of organic residues preserved in the argillaceous matrix of the interior of 36 ceramic vessels indicates that 7,500 years ago dairy products were already processed and consumed in the Central Pyrenees. The correlation between the residues of dairy fats and the different forms of the pottery suggests, moreover, that all the processes (preparation, consumption and storage) were carried out in both settlements.

This “questions previous considerations in which dairy consumption in the Pyrenees was thought to have begun much later,” points out Nàdia Tarifa, researcher from the University of Strasbourg when this study was conducted, and lead autor of the paper. “It was always thought that prehistoric social dynamics in mountainous regions were slower or ‘less evolved’ than in coastal regions. Our study adds solid proof to previous faunistic studies conducted in both sites, which had pointed to dairy farming in these mountainous regions at the very early stages of the Neolithic period,” Tarifa states.

The study also shows how pig-derived products may have been processed or stored in ceramic vessels at both sites, which would indicate the importance of this species for the early mountain farming economies. In contrast to the results for milk, researchers also observed variations between the two sites in terms of the exploitation of meat from ruminants and pigs, with a predominance of the former in Espluga de la Puyascada and the latter in Cueva de Chaves. These differences could be related to the characteristics of the settlements and their surroundings, and to the methods of meat processing.

The researchers also identified residues from processed vegetables, as well as from pine resin. The latter substance would have been used to waterproof the inside of the vessels.

The results support the idea that in the early Neolithic period in the Pyrenean area there was a mixed economy based on integrated agriculture and livestock farming (in which one supported the other), with sheep herds as the main source of meat and milk.

“Our findings provide a better understanding of consumption habits and the technological use of resources in the early Neolithic period in the Pyrenees and open up new avenues of research to deepen our understanding of the social and economic dynamics of ancient societies, especially in mountainous areas,” says Alejandro Sierra, researcher at the UAB and co-author of the study.



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A high-fat diet may fuel anxiety

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A high-fat diet may fuel anxiety


When stressed out, many of us turn to junk food for solace. But new University of Colorado Boulder research suggests this strategy may backfire.

The study found that in animals, a high-fat diet disrupts resident gut bacteria, alters behavior and, through a complex pathway connecting the gut to the brain, influences brain chemicals in ways that fuel anxiety.

“Everyone knows that these are not healthy foods, but we tend to think about them strictly in terms of a little weight gain,” said lead author Christopher Lowry, a professor of integrative physiology at CU Boulder. “If you understand that they also impact your brain in a way that can promote anxiety, that makes the stakes even higher.”

Lowry’s team divided adolescent rats into two groups: Half got a standard diet of about 11% fat for nine weeks; the others got a high-fat diet of 45% fat, consisting mostly of saturated fat from animal products.

The typical American diet is about 36% fat, according to the Centers for Disease Control and Prevention.

Throughout the study, the researchers collected fecal samples and assessed the animals’ microbiome, or gut bacteria. After nine weeks, the animals underwent behavioral tests.

When compared to the control group, the group eating a high-fat diet, not surprisingly, gained weight. But the animals also showed significantly less diversity of gut bacteria. Generally speaking, more bacterial diversity is associated with better health, Lowry explained. They also hosted far more of a category of bacteria called Firmicutes and less of a category called Bacteroidetes. A higher Firmicutes to Bacteroidetes ratio has been associated with the typical industrialized diet and with obesity.

The high-fat diet group also showed higher expression of three genes (tph2, htr1a, and slc6a4) involved in production and signaling of the neurotransmitter serotonin — particularly in a region of the brainstem known as the dorsal raphe nucleus cDRD, which is associated with stress and anxiety.

While serotonin is often billed as a “feel-good brain chemical,” Lowry notes that certain subsets of serotonin neurons can, when activated, prompt anxiety-like responses in animals. Notably, heightened expression of tph2, or tryptophan hydroxylase, in the cDRD has been associated with mood disorders and suicide risk in humans.

“To think that just a high-fat diet could alter expression of these genes in the brain is extraordinary,” said Lowry. “The high-fat group essentially had the molecular signature of a high anxiety state in their brain.”

Lowry suspects that an unhealthy microbiome compromises the gut lining, enabling bacteria to slip into the body’s circulation and communicate with the brain via the vagus nerve, a pathway from the gastrointestinal tract to the brain.

“If you think about human evolution, it makes sense,” Lowry said. “We are hard-wired to really notice things that make us sick so we can avoid those things in the future.”

Lowry stresses that not all fats are bad, and that healthy fats like those found in fish, olive oil, nuts and seeds can be anti-inflammatory and good for the brain.

His advice: Eat as many different kinds of fruits and vegetables as possible, add fermented foods to your diet to support a healthy microbiome and lay off the pizza and fries. Also, if you do have a hamburger, add a slice of avocado. Some research shows that good fat can counteract some of the bad.



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