Researchers at Wageningen University & Research in the Netherlands have produced crops in Mars and Moon soil simulant developed by NASA. The research supports the idea that it would not only be possible to grow food on Mars and the Moon to feed future settlers, but also to obtain viable seed from crops grown there.
Wieger Wamelink and his colleagues at Wageningen University & Research, cultivated ten different crops: garden cress, rocket, tomato, radish, rye, quinoa, spinach, chives, peas and leek. The researchers simulated the properties of Lunar and Martian regolith and "normal" soil (potting soil from Earth) as a control.
Nine of the ten crops sown grew well and edible parts were harvested from them. Spinach was the exception. Total biomass production per tray was the highest for the Earth control and Mars soil simulant that differed significantly from Moon soil simulant. The seeds produced by three species (radish, rye and garden cress) were tested successfully for germination.
The article, "Crop growth and viability of seeds on Mars and Moon soil simulants," by Wieger Wamelink and colleagues has been published in De Gruyter's open access journal, Open Agriculture.
"We were thrilled when we saw the first tomatoes ever grown on Mars soil simulant turning red. It meant that the next step towards a sustainable closed agricultural ecosystem had been taken," said Wieger Wamelink.
From Science Daily
Oct 15, 2019
Monkeys outperform humans when it comes to cognitive flexibility
When it comes to being willing to explore more efficient options to solving a problem, monkeys exhibit more cognitive flexibility than humans, according to a study by Georgia State University psychology researchers.
"We are a unique species and have various ways in which we are exceptionally different from every other creature on the planet," said Julia Watzek, a graduate student in psychology at Georgia State. "But we're also sometimes really dumb."
Watzek was the lead author of a paper published in Scientific Reports illustrating how capuchin and rhesus macaque monkeys were significantly less susceptible than humans to "cognitive set" bias when presented a chance to switch to a more efficient option. The research results supported earlier studies with fellow primates, baboons and chimpanzees, who also showed a greater willingness to use optional shortcuts to earn a treat compared to humans who persisted in using a familiar learned strategy despite its relative inefficiency.
"I think we're less and less surprised when primates outsmart humans sometimes," Watzek said.
The test involved establishing a specific strategy to lead to a solution. Through trial and error using a computer, monkeys and humans had to follow a pattern by pushing a striped square then a dotted square and then, when it appeared, a triangle to achieve the goal and receive a reward. For the humans, the reward was either a jingle or points to let them know they got it right. For the monkeys, it was a banana pellet. Wrong results got a brief timeout and no reward.
After the strategy was learned, subsequent trials presented the triangle option immediately without having to push the patterned squares in sequence. All of the monkeys quickly used the shortcut, while 61 percent of the humans did not. In fact, 70 percent of all the monkeys used the shortcut the very first time it was available compared to only one human. (The study involved 56 humans, 22 capuchin and 7 rhesus monkeys.)
"There's a heavy reliance on rote learning and doing it the way you were taught and to specifically not take the shortcut," Watzek said of the human subjects.
"More of the humans do take the shortcut after seeing a video of somebody taking the shortcut, but about 30 percent still don't," Watzek said." In another version we told them they shouldn't be afraid to try something new. More of them did use the shortcut then, but many of them still didn't."
The study illustrates how humans can suffer from learned biases that can lead us to make inefficient decisions and miss opportunities. Often, sticking with what's familiar and proven -- like a commuting route to work -- isn't a big deal with a low cost over an alternative. Other times, using inefficient, biased or outdated practices could have far-reaching consequences. An example would be the most recent global financial crisis when many experts ignored instability warnings and continued practicing risky trading and lending habits that led to a housing market crash.
"To set ourselves up for good decision-making, sometimes that means changing available options," Watzek said. "I'm not proposing to topple the entire Western education system, but it is interesting to think through ways in which we train our children to think a specific way and stay in the box and not outside of it. Just be mindful of it. There are good reasons for why we do what we do, but I think sometimes it can get us into a lot of trouble."
Study co-author Sarah Pope, a former graduate student in the Neuroscience Institute at Georgia State, took the experiment to Namibia and tested it on members of the semi-nomadic Himba tribe, which is not exposed to Western education and lives in a less predictable environment. While more were quicker to use the shortcut immediately, more than half still used the three-step approach as well. In tests of visitors at Zoo Atlanta, children 7-10 were four times more likely than adults to use the shortcut but still more than half continued to use the learned strategy.
Read more at Science Daily
"We are a unique species and have various ways in which we are exceptionally different from every other creature on the planet," said Julia Watzek, a graduate student in psychology at Georgia State. "But we're also sometimes really dumb."
Watzek was the lead author of a paper published in Scientific Reports illustrating how capuchin and rhesus macaque monkeys were significantly less susceptible than humans to "cognitive set" bias when presented a chance to switch to a more efficient option. The research results supported earlier studies with fellow primates, baboons and chimpanzees, who also showed a greater willingness to use optional shortcuts to earn a treat compared to humans who persisted in using a familiar learned strategy despite its relative inefficiency.
"I think we're less and less surprised when primates outsmart humans sometimes," Watzek said.
The test involved establishing a specific strategy to lead to a solution. Through trial and error using a computer, monkeys and humans had to follow a pattern by pushing a striped square then a dotted square and then, when it appeared, a triangle to achieve the goal and receive a reward. For the humans, the reward was either a jingle or points to let them know they got it right. For the monkeys, it was a banana pellet. Wrong results got a brief timeout and no reward.
After the strategy was learned, subsequent trials presented the triangle option immediately without having to push the patterned squares in sequence. All of the monkeys quickly used the shortcut, while 61 percent of the humans did not. In fact, 70 percent of all the monkeys used the shortcut the very first time it was available compared to only one human. (The study involved 56 humans, 22 capuchin and 7 rhesus monkeys.)
"There's a heavy reliance on rote learning and doing it the way you were taught and to specifically not take the shortcut," Watzek said of the human subjects.
"More of the humans do take the shortcut after seeing a video of somebody taking the shortcut, but about 30 percent still don't," Watzek said." In another version we told them they shouldn't be afraid to try something new. More of them did use the shortcut then, but many of them still didn't."
The study illustrates how humans can suffer from learned biases that can lead us to make inefficient decisions and miss opportunities. Often, sticking with what's familiar and proven -- like a commuting route to work -- isn't a big deal with a low cost over an alternative. Other times, using inefficient, biased or outdated practices could have far-reaching consequences. An example would be the most recent global financial crisis when many experts ignored instability warnings and continued practicing risky trading and lending habits that led to a housing market crash.
"To set ourselves up for good decision-making, sometimes that means changing available options," Watzek said. "I'm not proposing to topple the entire Western education system, but it is interesting to think through ways in which we train our children to think a specific way and stay in the box and not outside of it. Just be mindful of it. There are good reasons for why we do what we do, but I think sometimes it can get us into a lot of trouble."
Study co-author Sarah Pope, a former graduate student in the Neuroscience Institute at Georgia State, took the experiment to Namibia and tested it on members of the semi-nomadic Himba tribe, which is not exposed to Western education and lives in a less predictable environment. While more were quicker to use the shortcut immediately, more than half still used the three-step approach as well. In tests of visitors at Zoo Atlanta, children 7-10 were four times more likely than adults to use the shortcut but still more than half continued to use the learned strategy.
Read more at Science Daily
How mucus tames microbes
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| Illustration of bacterium Pseudomonas aeruginosa. |
A new study from MIT reveals that glycans -- branched sugar molecules found in mucus -- are responsible for most of this microbe-taming. There are hundreds of different glycans in mucus, and the MIT team discovered that these molecules can prevent bacteria from communicating with each other and forming infectious biofilms, effectively rendering them harmless.
"What we have in mucus is a therapeutic gold mine," says Katharina Ribbeck, the Mark Hyman, Jr. Career Development Professor of Biological Engineering at MIT. "These glycans have biological functions that are very broad and sophisticated. They have the ability to regulate how microbes behave and really tune their identity."
In this study, which appears today in Nature Microbiology, the researchers focused on glycans' interactions with Pseudomonas aeruginosa, an opportunistic pathogen that can cause infections in cystic fibrosis patients and people with compromised immune systems. Work now underway in Ribbeck's lab has shown that glycans can regulate the behavior of other microbes as well.
The lead author of the Nature Microbiology paper is MIT graduate student Kelsey Wheeler.
Powerful defenders
The average person produces several liters of mucus every day, and until recently this mucus was thought to function primarily as a lubricant and a physical barrier. However, Ribbeck and others have shown that mucus can actually interfere with bacterial behavior, preventing microbes from attaching to surfaces and communicating with one another.
In the new study, Ribbeck wanted to test whether glycans were involved in mucus' ability to control the behavior of microbes. These sugar molecules, a type of oligosaccharide, attach to proteins called mucins, the gel-forming building blocks of mucus, to form a bottlebrush-like structure. Mucus-associated glycans have been little studied, but Ribbeck thought they might play a major role in the microbe-disarming activity she had previously seen from mucus.
To explore that possibility, she isolated glycans and exposed them to Pseudomonas aeruginosa. Upon exposure to mucin glycans, the bacteria underwent broad shifts in behavior that rendered them less harmful to the host. For example, they no longer produced toxins, attached to or killed host cells, or expressed genes essential for bacterial communication.
This microbe-disarming activity had powerful consequences on the ability of this bacterium to establish infections. Ribbeck has shown that treatment of Pseudomonas-infected burn wounds with mucins and mucin glycans reduces bacterial proliferation, indicating the therapeutic potential of these virulence-neutralizing agents.
"We've seen that intact mucins have regulatory effects and can cause behavioral switches in a whole range of pathogens, but now we can pinpoint the molecular mechanism and the entities that are responsible for this, which are the glycans," Ribbeck says.
In these experiments, the researchers used collections of hundreds of glycans, but they now plan to study the effects of individual glycans, which may interact specifically with different pathways or different microbes.
Bacterial interactions
Pseudomonas aeruginosa is just one of many opportunistic pathogens that healthy mucus keeps in check. Ribbeck is now studying the role of glycans in regulating other pathogens, including Streptococcus and the fungus Candida albicans, and she is also working on identifying receptors on microbe cell surfaces that interact with glycans.
Her work on Streptococcus has shown that glycans can block horizontal gene transfer, a process that microbes often use to spread genes for drug resistance.
Ribbeck and other researchers are now interested in using what they have learned about mucins and glycans to develop artificial mucus, which could offer a new way to treat diseases stemming from lost or defective mucus.
Harnessing the powers of mucus could also lead to new ways to treat antibiotic-resistant infections, because it offers a complementary strategy to traditional antibiotics, Ribbeck says.
"What we find here is that nature has evolved the ability to disarm difficult microbes, instead of killing them. This would not only help limit selective pressure for developing resistance, because they are not under pressure to find ways to survive, but it should also help create and maintain a diverse microbiome," she says.
Ribbeck suspects that glycans in mucus also play a key role in determining the composition of the microbiome -- the trillions of bacterial cells that live inside the human body. Many of these microbes are beneficial to their human hosts, and glycans may be providing them with nutrients they need, or otherwise helping them to flourish, she says. In this way, mucus-associated glycans are similar to the many oligosaccharides found in human milk, which also contains a wide array of sugars that can regulate microbe behavior.
"This is a theme that is likely at play in many systems where the goal is to shape and manipulate communities inside the body, not just in humans but throughout the animal kingdom," Ribbeck says.
Read more at Science Daily
Oct 14, 2019
Evolutionary history of oaks
How oaks are related has long posed a challenge to scientists. Dr. Andrew Hipp, senior scientist at The Morton Arboretum, led an international team of 24 scientists to unravel the history of global oak diversity for the first time using DNA sequencing of 260 oak species, combined with genomic mapping and fossil data.
Fundamental questions about relationships between organisms and the genes that drive ecological diversification underlie the secrets of biodiversity. Understanding the past of this ecologically, economically and culturally important group provides a baseline of knowledge that will allow scientists to address additional questions about oaks and other trees, as well as help with conservation efforts.
"This paper demonstrates that oaks have repeatedly and globally diversified in response to ecological opportunity" says Hipp. "The changes in the global landscape have given us the gift of the oak diversity we observe today."
Patchwork of Histories
The new paper, to be published in New Phytologist, is available free through an Early View online for one month beginning October 14. The study provides the most detailed account to date of the evolutionary history of the world's oaks. Investigating which parts of the oak genome distinguish species from one another, researchers at The Morton Arboretum, in collaboration with 17 institutions around the world, discovered that each gene or stretch of DNA in the genome has the potential to record multiple histories; each section bears the history of speciation of one oak lineage, but it may record the history of hybridization for a different lineage. In other words, there is no one region of the genome that defines oaks: it is the patchwork of histories embedded in the genome that characterize the history of oak evolution.
In addition, this research shows that different oak lineages have repeatedly diversified in the same area. Red oaks, white oaks, ring-cupped oaks, turkey and cork oaks, and three of the other oak sections arose rapidly and segregated to either the Americas or Eurasia. All of these lineages can be found in part of their range with at least one other lineage. As oaks migrated, species interbred, hybridized and diversified opportunistically in response to changes in the landscape. The highest rates of species diversification have been in response to migrations into new territory. Over and over, oaks have taken advantage of ecological opportunity to produce the diversity we see today, providing humans with ships, homes, wine barrels, furniture and acorns to eat, and providing food and homes for countless insects, mammals, birds and fungi.
"For the first time, this paper demonstrates that the history of different [oak] lineages is driven by different sets of genes," said co-author Dr. Antoine Kremer from the French National Institute for Agricultural Research. "The story of oak evolution is especially fascinating due to the ecological and morphological convergence in different oak lineages that cohabit on the same continent."
Read more at Science Daily
Fundamental questions about relationships between organisms and the genes that drive ecological diversification underlie the secrets of biodiversity. Understanding the past of this ecologically, economically and culturally important group provides a baseline of knowledge that will allow scientists to address additional questions about oaks and other trees, as well as help with conservation efforts.
"This paper demonstrates that oaks have repeatedly and globally diversified in response to ecological opportunity" says Hipp. "The changes in the global landscape have given us the gift of the oak diversity we observe today."
Patchwork of Histories
The new paper, to be published in New Phytologist, is available free through an Early View online for one month beginning October 14. The study provides the most detailed account to date of the evolutionary history of the world's oaks. Investigating which parts of the oak genome distinguish species from one another, researchers at The Morton Arboretum, in collaboration with 17 institutions around the world, discovered that each gene or stretch of DNA in the genome has the potential to record multiple histories; each section bears the history of speciation of one oak lineage, but it may record the history of hybridization for a different lineage. In other words, there is no one region of the genome that defines oaks: it is the patchwork of histories embedded in the genome that characterize the history of oak evolution.
In addition, this research shows that different oak lineages have repeatedly diversified in the same area. Red oaks, white oaks, ring-cupped oaks, turkey and cork oaks, and three of the other oak sections arose rapidly and segregated to either the Americas or Eurasia. All of these lineages can be found in part of their range with at least one other lineage. As oaks migrated, species interbred, hybridized and diversified opportunistically in response to changes in the landscape. The highest rates of species diversification have been in response to migrations into new territory. Over and over, oaks have taken advantage of ecological opportunity to produce the diversity we see today, providing humans with ships, homes, wine barrels, furniture and acorns to eat, and providing food and homes for countless insects, mammals, birds and fungi.
"For the first time, this paper demonstrates that the history of different [oak] lineages is driven by different sets of genes," said co-author Dr. Antoine Kremer from the French National Institute for Agricultural Research. "The story of oak evolution is especially fascinating due to the ecological and morphological convergence in different oak lineages that cohabit on the same continent."
Read more at Science Daily
Astronomers use giant galaxy cluster as X-ray magnifying lens
Astronomers at MIT and elsewhere have used a massive cluster of galaxies as an X-ray magnifying glass to peer back in time, to nearly 9.4 billion years ago. In the process, they spotted a tiny dwarf galaxy in its very first, high-energy stages of star formation.
While galaxy clusters have been used to magnify objects at optical wavelengths, this is the first time scientists have leveraged these massive gravitational giants to zoom in on extreme, distant, X-ray-emitting phenomena.
What they detected appears to be a blue speck of an infant galaxy, about 1/10,000 the size of our Milky Way, in the midst of churning out its first stars -- supermassive, cosmically short-lived objects that emit high-energy X-rays, which the researchers detected in the form of a bright blue arc.
"It's this little blue smudge, meaning it's a very small galaxy that contains a lot of super-hot, very massive young stars that formed recently," says Matthew Bayliss, a research scientist in MIT's Kavli Institute for Astrophysics and Space Research. "This galaxy is similar to the very first galaxies that formed in the universe ... the kind of which no one has ever seen in X-ray in the distant universe before."
Bayliss says the detection of this single, distant galaxy is proof that scientists can use galaxy clusters as natural X-ray magnifiers, to pick out extreme, highly energetic phenomena in the universe's early history.
"With this technique, we could, in the future, zoom in on a distant galaxy and age-date different parts of it -- to say, this part has stars that formed 200 million years ago, versus another part that formed 50 million years ago, and pick them apart in a way you cannot otherwise do," says Bayliss, who will be moving on to the University of Cincinnati as an assistant professor of physics.
He and his co-authors, including Michael McDonald, assistant professor of physics at MIT, have published their results in the journal Nature Astronomy.
A candle in the light
Galaxy clusters are the most massive objects in the universe, composed of thousands of galaxies, all bound together by gravity as one enormous, powerful force. Galaxy clusters are so massive, and their gravitational pull is so strong, that they can distort the fabric of space-time, bending the universe and any surrounding light, much like an elephant would stretch and warp a trapeze net.
Scientists have used galaxy clusters as cosmic magnifying glasses, with a technique known as gravitational lensing. The idea is that if scientists can approximate the mass of a galaxy cluster, they can estimate its gravitational effects on any surrounding light, as well as the angle at which a cluster may deflect that light.
For instance, imagine if an observer, facing a galaxy cluster, were trying to detect an object, such as a single galaxy, behind that cluster. The light emitted by that object would travel straight toward the cluster, then bend around the cluster. It would continue traveling toward the observer, though at slightly different angles, appearing to the observer as mirrored images of the same object, which in the end can be combined as a single, "magnified" image.
Scientists have used galaxy clusters to magnify objects at optical wavelengths, but never in the X-ray band of the electromagnetic spectrum, mainly because galaxy clusters themselves emit an enormous amount of X-rays. Scientists have thought that any X-rays coming from a background source would be impossible to discern from the cluster's own glare.
"If you're trying to see an X-ray source behind a cluster, it's like trying to see a candle next to a really bright light," Bayliss says. "So we knew this was a challenging measurement to make."
X-ray subtraction
The researchers wondered: Could they subtract that bright light and see the candle behind it? In other words, could they remove the X-ray emissions coming from the galaxy cluster, to view the much fainter X-rays coming from an object, behind and magnified by the cluster?
The team tested this idea with observations taken by NASA's Chandra X-ray Observatory, one of the world's most powerful X-ray space telescopes. They looked in particular at Chandra's measurements of the Phoenix cluster, a distant galaxy cluster located 5.7 billion light-years from Earth, which has been estimated to be about a quadrillion times as massive as the sun, with gravitational effects that should make it a powerful, natural magnifying lens.
"The idea is to take whatever your best X-ray telescope is -- in this case, Chandra -- and use a natural lens to magnify and effectively make Chandra bigger, so you can see more distant things," Bayliss says.
He and his colleagues analyzed observations of the Phoenix cluster, taken continuously by Chandra for over a month. They also looked at images of the cluster taken by two optical and infrared telescopes -- the Hubble Space Telescope and the Magellan telescope in Chile. With all these various views, the team developed a model to characterize the cluster's optical effects, which allowed the researchers to precisely measure the X-ray emissions from the cluster itself, and subtract it from the data.
They were left with two similar patterns of X-ray emissions around the cluster, which they determined were "lensed," or gravitationally bent, by the cluster. When they traced the emissions backward in time, they found that they all originated from a single, distant source: a tiny dwarf galaxy from 9.4 billion years ago, when the universe itself was roughly 4.4 billion years old -- about a third of its current age.
"Previously, Chandra had seen only a handful of things at this distance," Bayliss says. "In less than 10 percent of the time, we discovered this object, similarly far away. And gravitational lensing is what let us do it."
The combination of Chandra and the Phoenix cluster's natural lensing power enabled the team to see the tiny galaxy hiding behind the cluster, magnified about 60 times. At this resolution, they were able to zoom in to discern two distinct clumps within the galaxy, one producing many more X-rays than the other.
As X-rays are typically produced during extreme, short-lived phenomena, the researchers believe that the first X-ray-rich clump signals a part of the dwarf galaxy that has very recently formed supermassive stars, while the quieter region is an older region that contains more mature stars.
Read more at Science Daily
While galaxy clusters have been used to magnify objects at optical wavelengths, this is the first time scientists have leveraged these massive gravitational giants to zoom in on extreme, distant, X-ray-emitting phenomena.
What they detected appears to be a blue speck of an infant galaxy, about 1/10,000 the size of our Milky Way, in the midst of churning out its first stars -- supermassive, cosmically short-lived objects that emit high-energy X-rays, which the researchers detected in the form of a bright blue arc.
"It's this little blue smudge, meaning it's a very small galaxy that contains a lot of super-hot, very massive young stars that formed recently," says Matthew Bayliss, a research scientist in MIT's Kavli Institute for Astrophysics and Space Research. "This galaxy is similar to the very first galaxies that formed in the universe ... the kind of which no one has ever seen in X-ray in the distant universe before."
Bayliss says the detection of this single, distant galaxy is proof that scientists can use galaxy clusters as natural X-ray magnifiers, to pick out extreme, highly energetic phenomena in the universe's early history.
"With this technique, we could, in the future, zoom in on a distant galaxy and age-date different parts of it -- to say, this part has stars that formed 200 million years ago, versus another part that formed 50 million years ago, and pick them apart in a way you cannot otherwise do," says Bayliss, who will be moving on to the University of Cincinnati as an assistant professor of physics.
He and his co-authors, including Michael McDonald, assistant professor of physics at MIT, have published their results in the journal Nature Astronomy.
A candle in the light
Galaxy clusters are the most massive objects in the universe, composed of thousands of galaxies, all bound together by gravity as one enormous, powerful force. Galaxy clusters are so massive, and their gravitational pull is so strong, that they can distort the fabric of space-time, bending the universe and any surrounding light, much like an elephant would stretch and warp a trapeze net.
Scientists have used galaxy clusters as cosmic magnifying glasses, with a technique known as gravitational lensing. The idea is that if scientists can approximate the mass of a galaxy cluster, they can estimate its gravitational effects on any surrounding light, as well as the angle at which a cluster may deflect that light.
For instance, imagine if an observer, facing a galaxy cluster, were trying to detect an object, such as a single galaxy, behind that cluster. The light emitted by that object would travel straight toward the cluster, then bend around the cluster. It would continue traveling toward the observer, though at slightly different angles, appearing to the observer as mirrored images of the same object, which in the end can be combined as a single, "magnified" image.
Scientists have used galaxy clusters to magnify objects at optical wavelengths, but never in the X-ray band of the electromagnetic spectrum, mainly because galaxy clusters themselves emit an enormous amount of X-rays. Scientists have thought that any X-rays coming from a background source would be impossible to discern from the cluster's own glare.
"If you're trying to see an X-ray source behind a cluster, it's like trying to see a candle next to a really bright light," Bayliss says. "So we knew this was a challenging measurement to make."
X-ray subtraction
The researchers wondered: Could they subtract that bright light and see the candle behind it? In other words, could they remove the X-ray emissions coming from the galaxy cluster, to view the much fainter X-rays coming from an object, behind and magnified by the cluster?
The team tested this idea with observations taken by NASA's Chandra X-ray Observatory, one of the world's most powerful X-ray space telescopes. They looked in particular at Chandra's measurements of the Phoenix cluster, a distant galaxy cluster located 5.7 billion light-years from Earth, which has been estimated to be about a quadrillion times as massive as the sun, with gravitational effects that should make it a powerful, natural magnifying lens.
"The idea is to take whatever your best X-ray telescope is -- in this case, Chandra -- and use a natural lens to magnify and effectively make Chandra bigger, so you can see more distant things," Bayliss says.
He and his colleagues analyzed observations of the Phoenix cluster, taken continuously by Chandra for over a month. They also looked at images of the cluster taken by two optical and infrared telescopes -- the Hubble Space Telescope and the Magellan telescope in Chile. With all these various views, the team developed a model to characterize the cluster's optical effects, which allowed the researchers to precisely measure the X-ray emissions from the cluster itself, and subtract it from the data.
They were left with two similar patterns of X-ray emissions around the cluster, which they determined were "lensed," or gravitationally bent, by the cluster. When they traced the emissions backward in time, they found that they all originated from a single, distant source: a tiny dwarf galaxy from 9.4 billion years ago, when the universe itself was roughly 4.4 billion years old -- about a third of its current age.
"Previously, Chandra had seen only a handful of things at this distance," Bayliss says. "In less than 10 percent of the time, we discovered this object, similarly far away. And gravitational lensing is what let us do it."
The combination of Chandra and the Phoenix cluster's natural lensing power enabled the team to see the tiny galaxy hiding behind the cluster, magnified about 60 times. At this resolution, they were able to zoom in to discern two distinct clumps within the galaxy, one producing many more X-rays than the other.
As X-rays are typically produced during extreme, short-lived phenomena, the researchers believe that the first X-ray-rich clump signals a part of the dwarf galaxy that has very recently formed supermassive stars, while the quieter region is an older region that contains more mature stars.
Read more at Science Daily
Reading the past like an open book: Researchers use text to measure 200 years of happiness
Was there such a thing as 'the good old days' when people were happier? Are current Government policies more or less likely to increase their citizens' feelings of wellbeing?
Using innovative new methods researchers at the University of Warwick, University of Glasgow Adam Smith Business School and The Alan Turing Institute in London have built a new index that uses data from books and newspaper to track levels of national happiness from 1820. Their research could help governments to make better decisions about policy priorities.
Governments the world over are making increasing use of "national happiness" data derived from surveys to help them consider the impact of policy on national wellbeing. Unfortunately, data for most countries is only available from 2011 onwards, and for a select few from the mid 1970s. This makes it hard to establish long-run trends, or to say anything about the main historical causes of happiness.
In order to tackle this problem, a team of researchers including Professor Thomas Hills (Warwick and The Alan Turing Institute), Professor Eugenio Proto (Glasgow), Professor Daniel Sgroi (Warwick), and Dr Chanuki Seresinhe (The Alan Turing Institute) took a key insight from psychology -- that more often than not what people say or write reveals much about their underlying happiness level -- and developed a method to apply it to online texts from millions of books and newspapers published over the past 200 years.
The main source of language used for the analysis was the Google Books corpus, a collection of word frequency data for over 8 million books -- that's more than 6 per cent of all books ever published.
The method uses psychological valence norms -- values of happiness that can be derived from text -- for thousands of words in di?erent languages to compute the relative proportion of positive and negative language for four di?erent nations (the USA, UK, Germany and Italy). The research team also controlled for the evolution of language, to take into account the fact that some words change their meaning over time.
The new index was validated against existing survey-based measures and proven to be an accurate guide to the national mood. One theory as to why books and newspaper articles are such a good source of data is that editors prefer to publish pieces which match the mood of their readers.
Studying the index, the researchers found that:
Commenting on the findings, Professor Thomas Hills said: "What's remarkable is that national subjective well-being is incredibly resilient to wars. Even temporary economic booms and busts have little long-term effect. We can see the American Civil War in our data, the revolutions of 48' across Europe, the roaring 20's and the Great Depression. But people quickly returned to their previous levels of subjective well-being after these events were over. Our national happiness is like an adjustable spanner that we open and close to calibrate our experiences against our recent past, with little lasting memory for the triumphs and tragedies of our age."
Professor Eugenio Proto added: "Our index is an important first step in understanding people's satisfaction in the past. Looking at the Italian data, it is interesting to note a slow but constant decline in the years of fascism and a dramatic decline in the years after the last crisis."
Professor Daniel Sgroi said: 'Aspirations seem to matter a lot: after the end of rationing in the 1950s national happiness was very high as were expectations for the future, but unfortunately things did not pan out as people might have hoped and national happiness fell for many years until the low-point of the Winter of Discontent.'
Read more at Science Daily
Using innovative new methods researchers at the University of Warwick, University of Glasgow Adam Smith Business School and The Alan Turing Institute in London have built a new index that uses data from books and newspaper to track levels of national happiness from 1820. Their research could help governments to make better decisions about policy priorities.
Governments the world over are making increasing use of "national happiness" data derived from surveys to help them consider the impact of policy on national wellbeing. Unfortunately, data for most countries is only available from 2011 onwards, and for a select few from the mid 1970s. This makes it hard to establish long-run trends, or to say anything about the main historical causes of happiness.
In order to tackle this problem, a team of researchers including Professor Thomas Hills (Warwick and The Alan Turing Institute), Professor Eugenio Proto (Glasgow), Professor Daniel Sgroi (Warwick), and Dr Chanuki Seresinhe (The Alan Turing Institute) took a key insight from psychology -- that more often than not what people say or write reveals much about their underlying happiness level -- and developed a method to apply it to online texts from millions of books and newspapers published over the past 200 years.
The main source of language used for the analysis was the Google Books corpus, a collection of word frequency data for over 8 million books -- that's more than 6 per cent of all books ever published.
The method uses psychological valence norms -- values of happiness that can be derived from text -- for thousands of words in di?erent languages to compute the relative proportion of positive and negative language for four di?erent nations (the USA, UK, Germany and Italy). The research team also controlled for the evolution of language, to take into account the fact that some words change their meaning over time.
The new index was validated against existing survey-based measures and proven to be an accurate guide to the national mood. One theory as to why books and newspaper articles are such a good source of data is that editors prefer to publish pieces which match the mood of their readers.
Studying the index, the researchers found that:
- Increases in national income do generate increases in national happiness but it takes a huge rise to have a noticeable effect at the national level
- An increase in longevity of one year had the same effect on happiness as a 4.3 per cent increase in GDP
- One less year of war had the equivalent effect on happiness of a 30 per cent rise in GDP
- In post-war UK the worst period for national happiness occurred around the appropriately named "Winter of Discontent."
- In post-war USA the lowest point of the index coincides with the Vietnam War and the evacuation of Saigon.
Commenting on the findings, Professor Thomas Hills said: "What's remarkable is that national subjective well-being is incredibly resilient to wars. Even temporary economic booms and busts have little long-term effect. We can see the American Civil War in our data, the revolutions of 48' across Europe, the roaring 20's and the Great Depression. But people quickly returned to their previous levels of subjective well-being after these events were over. Our national happiness is like an adjustable spanner that we open and close to calibrate our experiences against our recent past, with little lasting memory for the triumphs and tragedies of our age."
Professor Eugenio Proto added: "Our index is an important first step in understanding people's satisfaction in the past. Looking at the Italian data, it is interesting to note a slow but constant decline in the years of fascism and a dramatic decline in the years after the last crisis."
Professor Daniel Sgroi said: 'Aspirations seem to matter a lot: after the end of rationing in the 1950s national happiness was very high as were expectations for the future, but unfortunately things did not pan out as people might have hoped and national happiness fell for many years until the low-point of the Winter of Discontent.'
Read more at Science Daily
Dementia spreads via connected brain networks
In a new study, UC San Francisco scientists used maps of brain connections to predict how brain atrophy would spread in individual patients with frontotemporal dementia (FTD), adding to growing evidence that the loss of brain cells associated with dementia spreads via the synaptic connections between established brain networks. The results advance scientists' knowledge of how neurodegeneration spreads and could lead to new clinical tools to evaluate how well novel treatments slow or block the predicted trajectory of these diseases.
"Knowing how dementia spreads opens a window onto the biological mechanisms of the disease -- what parts of our cells or neural circuits are most vulnerable," said study lead author Jesse Brown, PhD, an assistant professor of neurology at the UCSF Memory and Aging Center and UCSF Weill Institute for Neurosciences. "You can't really design a treatment until you know what you're treating."
FTD, the most common form of dementia in people under the age of 60, comprises a group of neurodegenerative conditions with diverse linguistic and behavioral symptoms. As in Alzheimer's disease, the diversity of FTD symptoms reflects significant differences in how the neurodegenerative disease spreads through patients' brains. This variability makes it difficult for scientists searching for cures to pin down the biological drivers of brain atrophy and for clinical trials to evaluate whether a novel treatment is making a difference in the progression of a patient's disease.
Previous research by the study's senior author, William Seeley, MD, a professor of neurology and pathology at the Memory and Aging Center and Weill Institute, set off a sea change in dementia research by showing that patterns of brain atrophy in many forms of dementia map closely onto well-known brain networks -- groups of functionally related brain regions that work cooperatively via their synaptic connections, sometimes over long distances. In other words, Seeley's work proposed that neurodegenerative diseases don't spread evenly in all directions like a tumor, but can jump from one part of the brain to another along the anatomical circuits that wire these networks together.
In their new study -- published October 14 in Neuron -- Brown, Seeley and colleagues provided further evidence supporting this idea by examining how well neural network maps based on brain scans in healthy individuals could predict the spread of brain atrophy in FTD patients over the course of a year.
The researchers recruited 42 patients at the UCSF Memory and Aging Center with behavioral variant fronto-temporal dementia (bvFTD), a form of FTD that causes patients to exhibit inappropriate social behaviors, and 30 patients with semantic variant primary progressive aphasia (svPPA), a form of FTD that mainly impacts patients' language abilities. In their first visits to UCSF, each of these patients underwent a "baseline" MRI scan to assess the extent of existing brain degeneration and then had a follow-up scan about a year later to measure how their disease had progressed.
The researchers first estimated where the brain atrophy seen in each patient's baseline scans had begun, based on the hypothesis that brain degeneration begins in some particularly vulnerable location, then spreads out to anatomically connected brain regions. To do this, the researchers built standardized maps of the main functional partners of 175 different brain regions based on functional MRI (fMRI) scans of 75 healthy adults. They then identified which of these networks best matched the pattern of brain atrophy seen in a given FTD patient's baseline brain scans, and defined that network's central hub as the likely epicenter of the patient's degeneration.
They then used the same standardized connectivity maps to predict where the patient's brain atrophy was most likely to have spread in the follow-up scans done one year later, and compared the accuracy of these predictions to others that didn't take functional network connectivity into account.
They found that two particular connectivity measures significantly improved their predictions of a given brain region's chances of developing brain atrophy between the baseline and follow-up brain scans. One, called "shortest path to the epicenter," captured the number of synaptic "steps" that region was from the estimated disease epicenter -- essentially the number of links in the neural chain connecting the two areas -- while the other, called "nodal hazard," represented how many regions connected to a given region were already experiencing significant atrophy.
"It's like with an infectious disease, where your chances of becoming infected can be predicted by how many degrees of separation you have from 'Patient Zero' but also by how many people in your immediate social network are already sick," Brown said.
The researchers showed that on average these two measures of network connectivity did better at predicting the spread of disease to a new brain region than its simple straight-line distance from a patient's existing atrophy. In many cases the disease completely bypassed brain areas that were adjacent but not anatomically connected to already-atrophied regions, instead jumping to more functionally linked regions.
Although this method shows great promise, the researchers emphasize that it is not yet ready for clinical use. They hope to improve the accuracy of their predictions by -- among other approaches -- using individualized network maps for each patient rather than using average connectivity maps, and by developing more specialized prediction models for particular subtypes of FTD.
In addition to the biological insights the discovery provides about the mechanisms of spreading brain atrophy in FTD, which will inform ongoing efforts to develop treatments, the researchers also hope the findings will lead to improved metrics for evaluating therapies already entering clinical trials -- for instance by giving trial scientists early insights into whether the treatment is altering a predicted course of disease progression. Researchers could also use better predictions of how atrophy will spread through the brain to help prepare patients and their families for the symptoms they are likely to experience as their disease progresses.
"We are excited about this result because it represents an important first step toward a more precision medicine type of approach to predicting progression and measuring treatment effects in neurodegenerative disease," Seeley said.
In the future, Brown said, scientists might be able to develop therapies that specifically target the likely next site of disease and perhaps prevent atrophy from spreading from one region to another.
Read more at Science Daily
"Knowing how dementia spreads opens a window onto the biological mechanisms of the disease -- what parts of our cells or neural circuits are most vulnerable," said study lead author Jesse Brown, PhD, an assistant professor of neurology at the UCSF Memory and Aging Center and UCSF Weill Institute for Neurosciences. "You can't really design a treatment until you know what you're treating."
FTD, the most common form of dementia in people under the age of 60, comprises a group of neurodegenerative conditions with diverse linguistic and behavioral symptoms. As in Alzheimer's disease, the diversity of FTD symptoms reflects significant differences in how the neurodegenerative disease spreads through patients' brains. This variability makes it difficult for scientists searching for cures to pin down the biological drivers of brain atrophy and for clinical trials to evaluate whether a novel treatment is making a difference in the progression of a patient's disease.
Previous research by the study's senior author, William Seeley, MD, a professor of neurology and pathology at the Memory and Aging Center and Weill Institute, set off a sea change in dementia research by showing that patterns of brain atrophy in many forms of dementia map closely onto well-known brain networks -- groups of functionally related brain regions that work cooperatively via their synaptic connections, sometimes over long distances. In other words, Seeley's work proposed that neurodegenerative diseases don't spread evenly in all directions like a tumor, but can jump from one part of the brain to another along the anatomical circuits that wire these networks together.
In their new study -- published October 14 in Neuron -- Brown, Seeley and colleagues provided further evidence supporting this idea by examining how well neural network maps based on brain scans in healthy individuals could predict the spread of brain atrophy in FTD patients over the course of a year.
The researchers recruited 42 patients at the UCSF Memory and Aging Center with behavioral variant fronto-temporal dementia (bvFTD), a form of FTD that causes patients to exhibit inappropriate social behaviors, and 30 patients with semantic variant primary progressive aphasia (svPPA), a form of FTD that mainly impacts patients' language abilities. In their first visits to UCSF, each of these patients underwent a "baseline" MRI scan to assess the extent of existing brain degeneration and then had a follow-up scan about a year later to measure how their disease had progressed.
The researchers first estimated where the brain atrophy seen in each patient's baseline scans had begun, based on the hypothesis that brain degeneration begins in some particularly vulnerable location, then spreads out to anatomically connected brain regions. To do this, the researchers built standardized maps of the main functional partners of 175 different brain regions based on functional MRI (fMRI) scans of 75 healthy adults. They then identified which of these networks best matched the pattern of brain atrophy seen in a given FTD patient's baseline brain scans, and defined that network's central hub as the likely epicenter of the patient's degeneration.
They then used the same standardized connectivity maps to predict where the patient's brain atrophy was most likely to have spread in the follow-up scans done one year later, and compared the accuracy of these predictions to others that didn't take functional network connectivity into account.
They found that two particular connectivity measures significantly improved their predictions of a given brain region's chances of developing brain atrophy between the baseline and follow-up brain scans. One, called "shortest path to the epicenter," captured the number of synaptic "steps" that region was from the estimated disease epicenter -- essentially the number of links in the neural chain connecting the two areas -- while the other, called "nodal hazard," represented how many regions connected to a given region were already experiencing significant atrophy.
"It's like with an infectious disease, where your chances of becoming infected can be predicted by how many degrees of separation you have from 'Patient Zero' but also by how many people in your immediate social network are already sick," Brown said.
The researchers showed that on average these two measures of network connectivity did better at predicting the spread of disease to a new brain region than its simple straight-line distance from a patient's existing atrophy. In many cases the disease completely bypassed brain areas that were adjacent but not anatomically connected to already-atrophied regions, instead jumping to more functionally linked regions.
Although this method shows great promise, the researchers emphasize that it is not yet ready for clinical use. They hope to improve the accuracy of their predictions by -- among other approaches -- using individualized network maps for each patient rather than using average connectivity maps, and by developing more specialized prediction models for particular subtypes of FTD.
In addition to the biological insights the discovery provides about the mechanisms of spreading brain atrophy in FTD, which will inform ongoing efforts to develop treatments, the researchers also hope the findings will lead to improved metrics for evaluating therapies already entering clinical trials -- for instance by giving trial scientists early insights into whether the treatment is altering a predicted course of disease progression. Researchers could also use better predictions of how atrophy will spread through the brain to help prepare patients and their families for the symptoms they are likely to experience as their disease progresses.
"We are excited about this result because it represents an important first step toward a more precision medicine type of approach to predicting progression and measuring treatment effects in neurodegenerative disease," Seeley said.
In the future, Brown said, scientists might be able to develop therapies that specifically target the likely next site of disease and perhaps prevent atrophy from spreading from one region to another.
Read more at Science Daily
Scientists help immune system find hidden cancer cells
Cancer cells are masters at avoiding detection, but a new system developed by Yale scientists can make them stand out from the crowd and help the immune system spot and eliminate tumors that other forms of immunotherapies might miss, the researchers report Oct. 14 in the journal Nature Immunology.
The new system reduced or eliminated melanoma and triple-negative breast and pancreatic tumors in mice, even those located far from the primary tumor source, the researchers report.
"This is an entirely new form of immunotherapy," said Sidi Chen, assistant professor of genetics and senior author of the study.
Immunotherapy has revolutionized the treatment of cancer but existing therapies don't work on all patients or not at all against some cancers. Existing therapies sometimes fail to recognize all molecular disguises of cancer cells, rendering them less effective.
To address those shortcomings, Chen's lab developed a new system that weds viral gene therapy and CRISPR gene-editing technology. Instead of finding and editing pieces of DNA and inserting new genes, the new system -- called Multiplexed Activation of Endogenous Genes as Immunotherapy (MAEGI) -- launches a massive hunt of tens of thousands of cancer-related genes and then acts like a GPS to mark their location and amplify the signals.
MAEGI marks the tumor cells for immune destruction, which turns a cold tumor (lacking immune cells) into a hot tumor (with immune cells). It is the molecular equivalent of dressing tumor cells in orange jump suits, allowing the immune system police to quickly find and eradicate the deadly cells, Chen said.
"And once those cells are identified, the immune system immediately recognizes them if they show up in the future," Chen said.
The new system in theory should be effective against many cancer types, including those currently resistant to immunotherapy, he said.
Upcoming studies will optimize the system for simpler manufacturing and prepare for clinical trials in cancer patients.
From Science Daily
The new system reduced or eliminated melanoma and triple-negative breast and pancreatic tumors in mice, even those located far from the primary tumor source, the researchers report.
"This is an entirely new form of immunotherapy," said Sidi Chen, assistant professor of genetics and senior author of the study.
Immunotherapy has revolutionized the treatment of cancer but existing therapies don't work on all patients or not at all against some cancers. Existing therapies sometimes fail to recognize all molecular disguises of cancer cells, rendering them less effective.
To address those shortcomings, Chen's lab developed a new system that weds viral gene therapy and CRISPR gene-editing technology. Instead of finding and editing pieces of DNA and inserting new genes, the new system -- called Multiplexed Activation of Endogenous Genes as Immunotherapy (MAEGI) -- launches a massive hunt of tens of thousands of cancer-related genes and then acts like a GPS to mark their location and amplify the signals.
MAEGI marks the tumor cells for immune destruction, which turns a cold tumor (lacking immune cells) into a hot tumor (with immune cells). It is the molecular equivalent of dressing tumor cells in orange jump suits, allowing the immune system police to quickly find and eradicate the deadly cells, Chen said.
"And once those cells are identified, the immune system immediately recognizes them if they show up in the future," Chen said.
The new system in theory should be effective against many cancer types, including those currently resistant to immunotherapy, he said.
Upcoming studies will optimize the system for simpler manufacturing and prepare for clinical trials in cancer patients.
From Science Daily
Oct 13, 2019
Archaeology: Social inequality in Bronze Age households
Archaeogenetic analyses provide new insights into social inequality 4000 years ago: nuclear families lived together with foreign women and individuals from lower social classes in the same household.
Social inequality already existed in southern Germany 4000 years ago, even within one household, a new study published in the journal Science finds. Archaeological and archaeogenetic analyses of Bronze Age cemeteries in the Lech Valley, near Augsburg, show that families of biologically related persons with higher status lived together with unrelated women who came from afar and also had a high status, according to their grave goods. In addition, a larger number of local but clearly less well-off individuals were found in the same cemeteries, which were small gravesites associated with single homesteads. The researchers conclude that social inequality was already part of households structures in that time and region. Whether the less well-off individuals were servants or slaves can only be speculated upon.
In Central Europe, the Bronze Age covers the period from 2200 to 800 BCE. At that time people acquired the ability to cast bronze. This knowledge led to an early globalization, since the raw materials had to be transported across Europe. In an earlier study, the current team had shown that, 4000 years ago, the majority of women in the Lech Valley came from abroad and may have played a decisive role in the transfer of knowledge. Supraregional networks were apparently fostered by marriages and institutionalized forms of mobility.
The current archaeological-scientific project was situated at the Heidelberg Academy of Sciences and led by Philipp Stockhammer from the Ludwig-Maximilians-Universitaet (LMU) in Munich together with Johannes Krause and Alissa Mittnik from the Max Planck Institute for the Science of Human History in Jena and the University of Tübingen. The researchers attempted to investigate the effects of this mobility and other concurrent changes. The excavations south of Augsburg, which took place at the sites of Bronze Age homestead farms and their associated graveyards, enabled archaeologists to zoom into the Bronze Age in unprecedented resolution in order to investigate how the transition from the Stone Age to the Bronze Age affected the households of that time. "Wealth was correlated with either biological kinship or foreign origin. The nuclear family passed on their property and status over generations. But at every farm we also found poorly equipped people of local origin," says Philipp Stockhammer, Professor of Prehistoric Archaeology at LMU Munich. This finding suggests a complex social structure of households, as is also known from Classical Greece and Rome. In Roman times, slaves were also part of the family unit, but had a different social status. However, these people in the Lech Valley lived over 1500 years earlier. "This shows how long the history of social inequality in family structures goes back in time," Stockhammer continues.
Stable social structures over 700 years
It was already known that the first larger hierarchical social structures evolved in the Bronze Age. The findings of the current study were surprising in that social differences existed within a single household and were maintained over generations.
Grave goods can reveal the social status of the deceased to archaeologists. In the Lech Valley, weapons and elaborate jewelry were only found in the graves of closely related family members and women who came into the family from long distances, up to several hundred kilometers away. Other unrelated individuals of local origin were found in the same cemeteries without such high-status grave goods.
This study also succeeded in reconstructing for the first time family trees from prehistoric cemeteries spanning four to five generations. Surprisingly, however, these only included the male lineages. The female descendants apparently left the farms where they reached adulthood. The mothers of the sons, on the other hand, were all women who had moved in from afar. "Archaeogenetics provides us with a completely new view of the past. Until recently, we would not have thought it possible to examine marriage rules, social structure and social inequality in prehistory," says Johannes Krause, Director of the Department of Archaeogenetics at the Max Planck Institute for Human History.
Read more at Science Daily
Social inequality already existed in southern Germany 4000 years ago, even within one household, a new study published in the journal Science finds. Archaeological and archaeogenetic analyses of Bronze Age cemeteries in the Lech Valley, near Augsburg, show that families of biologically related persons with higher status lived together with unrelated women who came from afar and also had a high status, according to their grave goods. In addition, a larger number of local but clearly less well-off individuals were found in the same cemeteries, which were small gravesites associated with single homesteads. The researchers conclude that social inequality was already part of households structures in that time and region. Whether the less well-off individuals were servants or slaves can only be speculated upon.
In Central Europe, the Bronze Age covers the period from 2200 to 800 BCE. At that time people acquired the ability to cast bronze. This knowledge led to an early globalization, since the raw materials had to be transported across Europe. In an earlier study, the current team had shown that, 4000 years ago, the majority of women in the Lech Valley came from abroad and may have played a decisive role in the transfer of knowledge. Supraregional networks were apparently fostered by marriages and institutionalized forms of mobility.
The current archaeological-scientific project was situated at the Heidelberg Academy of Sciences and led by Philipp Stockhammer from the Ludwig-Maximilians-Universitaet (LMU) in Munich together with Johannes Krause and Alissa Mittnik from the Max Planck Institute for the Science of Human History in Jena and the University of Tübingen. The researchers attempted to investigate the effects of this mobility and other concurrent changes. The excavations south of Augsburg, which took place at the sites of Bronze Age homestead farms and their associated graveyards, enabled archaeologists to zoom into the Bronze Age in unprecedented resolution in order to investigate how the transition from the Stone Age to the Bronze Age affected the households of that time. "Wealth was correlated with either biological kinship or foreign origin. The nuclear family passed on their property and status over generations. But at every farm we also found poorly equipped people of local origin," says Philipp Stockhammer, Professor of Prehistoric Archaeology at LMU Munich. This finding suggests a complex social structure of households, as is also known from Classical Greece and Rome. In Roman times, slaves were also part of the family unit, but had a different social status. However, these people in the Lech Valley lived over 1500 years earlier. "This shows how long the history of social inequality in family structures goes back in time," Stockhammer continues.
Stable social structures over 700 years
It was already known that the first larger hierarchical social structures evolved in the Bronze Age. The findings of the current study were surprising in that social differences existed within a single household and were maintained over generations.
Grave goods can reveal the social status of the deceased to archaeologists. In the Lech Valley, weapons and elaborate jewelry were only found in the graves of closely related family members and women who came into the family from long distances, up to several hundred kilometers away. Other unrelated individuals of local origin were found in the same cemeteries without such high-status grave goods.
This study also succeeded in reconstructing for the first time family trees from prehistoric cemeteries spanning four to five generations. Surprisingly, however, these only included the male lineages. The female descendants apparently left the farms where they reached adulthood. The mothers of the sons, on the other hand, were all women who had moved in from afar. "Archaeogenetics provides us with a completely new view of the past. Until recently, we would not have thought it possible to examine marriage rules, social structure and social inequality in prehistory," says Johannes Krause, Director of the Department of Archaeogenetics at the Max Planck Institute for Human History.
Read more at Science Daily
Rare sleep disorder common among veterans with PTSD
Military veterans with post-traumatic stress disorder or concussion suffer from a thrashing form of sleep behavior at a rate that is far higher than the general population, according to a new study by researchers at the VA Portland Health Care System and Oregon Health & Science University. The finding was published online this week in the journal SLEEP.
Researchers next want to probe whether the disorder, known as REM sleep behavior disorder, or RBD, might provide an early signal of the development of neurodegenerative conditions such as Parkinson's disease.
Normally during sleep that coincides with rapid eye movement, or REM sleep, muscles are effectively paralyzed. In cases of RBD, brain control of muscle paralysis is impaired, resulting in people acting out dreams during REM sleep, sometimes causing injuries to themselves or their partners. It is estimated to effect less than 1% of the general population.
That proportion rose to 9% of the 394 veterans in this study, and further swelled to 21% among those with PTSD.
"This is important because, in the general population, RBD has been linked to Parkinson's disease, and RBD often precedes classic symptoms of Parkinson's by years," said senior author Miranda Lim, M.D., Ph.D., a staff physician at the VA and assistant professor of neurology, medicine and behavioral neuroscience in the OHSU School of Medicine. "We don't know whether veterans who have PTSD and higher rates of RBD will go on to develop Parkinson's, but it is an important question we need to answer."
Researchers suspect chronic stress on the brain may play a role in causing the sleep disorder in veterans with PTSD, as many veterans have been exposed to concussion which potentially accelerates neurodegenerative processes.
Each study participant underwent an overnight sleep study at the VA Portland Health Care System between 2015 and 2017 to determine the presence of dream enactment during episodes of REM sleep. Muscle activity was monitored continuously during the 8 hours of the study in order to diagnose RBD. The study found that those with PTSD had over 2-fold increased odds of RBD compared to veterans without PTSD.
"RBD seems to be highly prevalent in veterans with a history of trauma," said lead author Jonathan Elliott, Ph.D., a research physiologist at the Portland VA and assistant professor of neurology in the OHSU School of Medicine.
Doctors involved in the study, including co-authors Kristianna Weymann, Ph.D., R.N., a clinical assistant professor in OHSU School of Nursing, and Dennis Pleshakov, a student at the OHSU School of Medicine, will continue to track research participants with RBD, looking for early signs of Parkinson's or other neurodegenerative conditions.
Although there are several therapies to ease some of the symptoms of Parkinson's, including tremor and fatigue, so far there has been no definitive therapy to prevent it.
Clinical trials for promising therapies are usually conducted well after patients have been diagnosed with Parkinson's, at a stage which may be too late to reverse the symptoms. Lim said that identifying patients with RBD presents an opportunity to identify people earlier in the disease course, and potentially provides a more viable window to test promising interventions.
Read more at Science Daily
Researchers next want to probe whether the disorder, known as REM sleep behavior disorder, or RBD, might provide an early signal of the development of neurodegenerative conditions such as Parkinson's disease.
Normally during sleep that coincides with rapid eye movement, or REM sleep, muscles are effectively paralyzed. In cases of RBD, brain control of muscle paralysis is impaired, resulting in people acting out dreams during REM sleep, sometimes causing injuries to themselves or their partners. It is estimated to effect less than 1% of the general population.
That proportion rose to 9% of the 394 veterans in this study, and further swelled to 21% among those with PTSD.
"This is important because, in the general population, RBD has been linked to Parkinson's disease, and RBD often precedes classic symptoms of Parkinson's by years," said senior author Miranda Lim, M.D., Ph.D., a staff physician at the VA and assistant professor of neurology, medicine and behavioral neuroscience in the OHSU School of Medicine. "We don't know whether veterans who have PTSD and higher rates of RBD will go on to develop Parkinson's, but it is an important question we need to answer."
Researchers suspect chronic stress on the brain may play a role in causing the sleep disorder in veterans with PTSD, as many veterans have been exposed to concussion which potentially accelerates neurodegenerative processes.
Each study participant underwent an overnight sleep study at the VA Portland Health Care System between 2015 and 2017 to determine the presence of dream enactment during episodes of REM sleep. Muscle activity was monitored continuously during the 8 hours of the study in order to diagnose RBD. The study found that those with PTSD had over 2-fold increased odds of RBD compared to veterans without PTSD.
"RBD seems to be highly prevalent in veterans with a history of trauma," said lead author Jonathan Elliott, Ph.D., a research physiologist at the Portland VA and assistant professor of neurology in the OHSU School of Medicine.
Doctors involved in the study, including co-authors Kristianna Weymann, Ph.D., R.N., a clinical assistant professor in OHSU School of Nursing, and Dennis Pleshakov, a student at the OHSU School of Medicine, will continue to track research participants with RBD, looking for early signs of Parkinson's or other neurodegenerative conditions.
Although there are several therapies to ease some of the symptoms of Parkinson's, including tremor and fatigue, so far there has been no definitive therapy to prevent it.
Clinical trials for promising therapies are usually conducted well after patients have been diagnosed with Parkinson's, at a stage which may be too late to reverse the symptoms. Lim said that identifying patients with RBD presents an opportunity to identify people earlier in the disease course, and potentially provides a more viable window to test promising interventions.
Read more at Science Daily
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