Feb 18, 2020

Discovery at 'flower burial' site could unravel mystery of Neanderthal death rites

Illustration of primitive man in cave.
The first articulated Neanderthal skeleton to come out of the ground for over 20 years has been unearthed at one of the most important sites of mid-20th century archaeology: Shanidar Cave, in the foothills of Iraqi Kurdistan.

Researchers say the new find offers an unparalleled opportunity to investigate the "mortuary practices" of this lost species using the latest technologies.

Shanidar Cave was excavated in the 1950s, when archaeologist Ralph Solecki uncovered partial remains of ten Neanderthal men, women and children.

Some were clustered together, with clumps of ancient pollen surrounding one of the skeletons. Solecki claimed this showed Neanderthals buried their dead and conducted funerary rites with flowers.

The 'flower burial' captured the public imagination, and prompted a reappraisal of a species that -- prior to Shanidar Cave -- was thought to have been dumb and animalistic.

It also sparked a decades-long controversy over whether evidence from this extraordinary site did actually point to death rituals, or burial of any kind, and if Neanderthals were really capable of such cultural sophistication.

More than 50 years later, a team of researchers have reopened the old Solecki trench to collect new sediment samples, and discovered the crushed skull and torso bones of another Shanidar Neanderthal.

The discovery has been named Shanidar Z by researchers from Cambridge, Birkbeck and Liverpool John Moores universities.

The work was conducted in conjunction with the Kurdistan General Directorate of Antiquities and the Directorate of Antiquities for Soran Province. The find is announced today in a paper published in the journal Antiquity.

"So much research on how Neanderthals treated their dead has to involve returning to finds from sixty or even a hundred years ago, when archaeological techniques were more limited, and that only ever gets you so far," said Dr Emma Pomeroy, from Cambridge's Department of Archaeology, lead author of the new paper.

"To have primary evidence of such quality from this famous Neanderthal site will allow us to use modern technologies to explore everything from ancient DNA to long-held questions about Neanderthal ways of death, and whether they were similar to our own."

Ralph Solecki died last year aged 101, having never managed to conduct further excavations at his most famous site, despite several attempts.

In 2011, the Kurdish Regional Government approached Professor Graeme Barker from Cambridge's McDonald Institute of Archaeology about revisiting Shanidar Cave. With Solecki's enthusiastic support, initial digging began in 2014, but stopped after two days when ISIS got too close. It resumed the following year.

"We thought with luck we'd be able to find the locations where they had found Neanderthals in the 1950s, to see if we could date the surrounding sediments," said Barker. "We didn't expect to find any Neanderthal bones."

In 2016, in one of the deepest parts of the trench, a rib emerged from the wall, followed by a lumbar vertebra, then the bones of a clenched right hand. However, metres of sediment needed carefully digging out before the team could excavate the skeleton.

During 2018-19 they went on to uncover a complete skull, flattened by thousands of years of sediment, and upper body bones almost to the waist -- with the left hand curled under the head like a small cushion.

Early analysis suggests it is over 70,000 years old. While the sex is yet to be determined, the latest Neanderthal discovery has the teeth of a "middle- to older-aged adult."

Shanidar Z has now been brought on loan to the archaeological labs at Cambridge, where it is being conserved and scanned to help build a digital reconstruction, as more layers of silt are removed.

The team is also working on sediment samples from around the new find, looking for signs of climate change in fragments of shell and bone from ancient mice and snails, as well as traces of pollen and charcoal that could offer insight into activities such as cooking and the famous 'flower burial'.

Four of the Neanderthals, including the 'flower burial' and the latest find, formed what researchers describe as a "unique assemblage." It raises the question of whether Neanderthals were returning to the same spot within the cave to inter their dead.

A prominent rock next to the head of Shanidar Z may have been used as a marker for Neanderthals repeatedly depositing their dead, says Pomeroy, although whether time between deaths was weeks, decades or even centuries will be difficult to determine.

"The new excavation suggests that some of these bodies were laid in a channel in the cave floor created by water, which had then been intentionally dug to make it deeper," said Barker. "There is strong early evidence that Shanidar Z was deliberately buried."

CT-scans in Cambridge have revealed the petrous bone -- one of the densest in the body; a wedge at the base of the skull -- to be intact, offering hope of retrieving ancient Neanderthal DNA from the hot, dry region where "interbreeding" most likely took place as humans spilled out of Africa.

Added Pomeroy: "In recent years we have seen increasing evidence that Neanderthals were more sophisticated than previously thought, from cave markings to use of decorative shells and raptor talons.

Read more at Science Daily

Warming, acidic oceans may nearly eliminate coral reef habitats by 2100

Coral bleaching.
Rising sea surface temperatures and acidic waters could eliminate nearly all existing coral reef habitats by 2100, suggesting restoration projects in these areas will likely meet serious challenges, according to new research presented in San Diego at the Ocean Sciences Meeting 2020.

Scientists project 70 to 90 percent of coral reefs will disappear over the next 20 years as a result of climate change and pollution. Some groups are attempting to curb this decline by transplanting live corals grown in a lab to dying reefs. They propose new, young corals will boost the reef's recovery and bring it back to a healthy state.

But new research mapping where such restoration efforts would be most successful over the coming decades finds that by 2100, few to zero suitable coral habitats will remain. The preliminary findings suggest sea surface temperature and acidity are the most important factors in determining if a site is suitable for restoration.

"By 2100, it's looking quite grim," said Renee Setter, a biogeographer at the University of Hawaii Manoa who will present the new findings.

The results highlight some of the devastating impacts Earth's warming climate will have on marine life, according to the researchers. Although pollution poses numerous threats to ocean creatures, the new research suggests corals are most at risk from emission-driven changes in their environment.

"Trying to clean up the beaches is great and trying to combat pollution is fantastic. We need to continue those efforts," Setter said. "But at the end of the day, fighting climate change is really what we need to be advocating for in order to protect corals and avoid compounded stressors."

Projecting the future of coral reefs

Coral reefs around the globe face uncertain futures as ocean temperatures continue to climb. Warmer waters stress corals, causing them to release symbiotic algae living inside them. This turns typically vibrant-colored communities of corals white, a process called bleaching. Bleached corals are not dead, but they are at higher risk of dying, and these bleaching events are becoming more common under climate change.

In the new study, Setter and her colleagues mapped what areas of the ocean would be suitable for coral restoration efforts over the coming decades. The researchers simulated ocean environment conditions like sea surface temperature, wave energy, acidity of the water, pollution, and overfishing in areas where corals now exist. To factor in pollution and overfishing, the researchers considered human population density and land cover use to project how much waste would be released into the surrounding waters.

The researchers found most of parts of the ocean where coral reefs exist today won't be suitable habitats for corals by 2045, and the situation worsened as the simulation extended to 2100.

"Honestly, most sites are out," Setter said. The few sites that are viable by 2100 included only small portions of Baja California and the Red Sea, which are not ideal locations for coral reefs because of their proximity to rivers.

Read more at Science Daily

Reproductive genome from the laboratory

DNA illustration
The field of synthetic biology does not only observe and describe processes of life but also mimics them. A key characteristic of life is the ability to ability for replication, which means the maintenance of a chemical system. Scientists at the Max Planck Institute of Biochemistry in Martinsried generated a system, which is able to regenerate parts of its own DNA and protein building blocks.

In the field of synthetic biology, researchers investigate so-called "bottom-up" processes, which means the generation of life mimicking systems from inanimate building blocks. One of the most fundamental characteristics of all living organism is the ability to conserve and reproduce itself as distinct entities. However, the artificial "bottom-up" approach to create a system, which is able to replicate itself, is a great experimental challenge. For the first time, scientists have succeeded in overcoming this hurdle and synthesizing such a system.

Hannes Mutschler, head of the research group "Biomimetic Systems" at the Max Planck Institute for Biochemistry, and his team are dedicated to imitate the replication of genomes and protein synthesis with a "bottom-up" approach. Both processes are fundamental for the self-preservation and reproduction of biological systems. The researchers now succeeded in producing an in vitro system, in which both processes could take place simultaneously. "Our system is able to regenerate a significant proportion of its molecular components itself," explains Mutschler.

In order to start this process, the researchers needed a construction manual as well as various molecular "machines" and nutrients. Translated into biological terms, this means the construction manual is DNA, which contains the information to produce proteins. Proteins are often referred to as "molecular machines" because they often act as catalysts, which accelerate biochemical reactions in organisms. The basic building blocks of DNA are the so-called nucleotides. Proteins are made of amino acids.

Modular structure of the construction manual

Specifically, the researchers have optimized an in vitro expression system that synthesizes proteins based on a DNA blueprint. Due to several improvements, the in vitro expression system is now able to synthesize proteins, known as DNA polymerases, very efficiently. These DNA polymerases then replicate the DNA using nucleotides. Kai Libicher, first author of the study, explains: "Unlike previous studies, our system is able to read and copy comparatively long DNA genomes.

The scientists assembled the artificial genomes from up to eleven ring-shaped pieces of DNA. This modular structure enables them to insert or remove certain DNA segments easily. The largest modular genome reproduced by the researchers in the study consists of more than 116,000 base pairs, reaching the genome length of very simply cells.

Regeneration of proteins

Apart from encoding polymerases that are important for DNA replication, the artificial genome contains blueprints for further proteins, such as 30 translation factors originating from the bacterium Escherischia coli. Translation factors are important for the translation of the DNA blueprint into the respective proteins. Thus, they are essential for self-replicating systems, which imitate biochemical processes. In order to show that the new in vitro expression system is not only able to reproduce DNA, but is also able to produce its own translation factors, the researchers used mass spectrometry. With this analytic method, they determined the amount of proteins produced by the system.

Surprisingly, some of the translation factors were even present in larger quantities after the reaction than added before. According to the researchers, this is an important step towards a continuously self-replicating system that mimics biological processes.

Read more at Science Daily

Researchers Were Not Right About Left Brains, Study Suggests

Left and right sides of brain illustration.
The left and right side of the brain are involved in different tasks. This functional lateralization and associated brain asymmetry are well documented in humans, but little is known about brain asymmetry in our closest living relatives, the great apes. Using endocasts (imprints of the brain on cranial bones), scientists now challenge the long-held notion that the human pattern of brain asymmetry is unique. They found the same asymmetry pattern in chimpanzees, gorillas, and orangutans. However, humans were the most variable in this pattern. This suggests that lateralized, uniquely human cognitive abilities, such as language, evolved by adapting a presumably ancestral asymmetry pattern.

The left and right side of our brain are specialized for some cognitive abilities. For example, in humans, language is processed predominantly in the left hemisphere, and the right hand is controlled by the motor cortex in the left hemisphere. The functional lateralization is reflected by morphological asymmetry of the brain. Left and right hemisphere differ subtly in brain anatomy, the distribution of nerve cells, their connectivity and neurochemistry. Asymmetries of outer brain shape are even visible on endocasts. Most humans have a combination of a more projecting left occipital lobe (located in the back of the brain) with a more projecting right frontal lobe. Brain asymmetry is commonly interpreted as crucial for human brain function and cognition because it reflects functional lateralization. However, comparative studies among primates are rare and it is not known which aspects of brain asymmetry are really uniquely human. Based on previously available data, scientists assumed that many aspects of brain asymmetry evolved only recently, after the split between the human lineage from the lineage of our closest living relatives, the chimpanzees.

In a new paper researchers from the Max Planck Institute for Evolutionary Anthropology and the University of Vienna measured the magnitude and pattern of shape asymmetry of endocasts from humans and apes. "Great ape brains are rarely available for study, but we have developed methods to extract brain asymmetry data from skulls, which are easier to access. This made our study possible in the first place," says lead author Simon Neubauer.

The team found that the magnitude of asymmetry was about the same in humans and most great apes. Only chimpanzees were, on average, less asymmetric than humans, gorillas, and orangutans. They also investigated the pattern of asymmetry and could demonstrate that not only humans, but also chimpanzees, gorillas, and orangutans showed the asymmetry pattern previously described as typically human: the left occipital lobe, the right frontal lobe, as well as the right temporal pole and the right cerebellar lobe projecting more relatively to their contralateral parts. "What surprised us even more," says Philipp Mitteroecker, a co-author of the study, "was that humans were least consistent in this asymmetry with a lot of individual variation around the most common pattern." The authors interpret this as a sign of increased functional and developmental modularization of the human brain. For example, the differential projections of the occipital lobe and the cerebellum are less correlated in humans than in great apes. This finding is interesting because the cerebellum in humans underwent dramatic evolutionary changes and it seems that thereby its asymmetry was affected as well.

Read more at Science Daily

Feb 17, 2020

Breakthrough Listen releases 2 petabytes of data from SETI survey of Milky Way

The Breakthrough Listen Initiative today (Friday, Feb. 14) released data from the most comprehensive survey yet of radio emissions from the plane of the Milky Way Galaxy and the region around its central black hole, and it is inviting the public to search the data for signals from intelligent civilizations.

At a media briefing today in Seattle as part of the annual meeting of the American Association for the Advancement of Science (AAAS), Breakthrough Listen principal investigator Andrew Siemion of the University of California, Berkeley, announced the release of nearly 2 petabytes of data, the second data dump from the four-year old search for extraterrestrial intelligence (SETI). A petabyte of radio and optical telescope data was released last June, the largest release of SETI data in the history of the field.

The data, most of it fresh from the telescope prior to detailed study from astronomers, comes from a survey of the radio spectrum between 1 and 12 gigahertz (GHz). About half of the data comes via the Parkes radio telescope in New South Wales, Australia, which, because of its location in the Southern Hemisphere, is perfectly situated and instrumented to scan the entire galactic disk and galactic center. The telescope is part of the Australia Telescope National Facility, owned and managed by the country's national science agency, CSIRO.

The remainder of the data was recorded by the Green Bank Observatory in West Virginia, the world's largest steerable radio dish, and an optical telescope called the Automated Planet Finder, built and operated by UC Berkeley and located at Lick Observatory outside San Jose, California.

"Since Breakthrough Listen's initial data release last year, we have doubled what is available to the public," said Breakthrough Listen's lead system administrator, Matt Lebofsky. "It is our hope that these data sets will reveal something new and interesting, be it other intelligent life in the universe or an as-yet-undiscovered natural astronomical phenomenon."

The National Radio Astronomy Observatory (NRAO) and the privately-funded SETI Institute in Mountain View, California, also announced today an agreement to collaborate on new systems to add SETI capabilities to radio telescopes operated by NRAO. The first project will develop a system to piggyback on the National Science Foundation's Karl G. Jansky Very Large Array (VLA) in New Mexico and provide data to state-of-the-art digital backend equipment built by the SETI Institute.

"The SETI Institute will develop and install an interface on the VLA, permitting unprecedented access to the rich data stream continuously produced by the telescope as it scans the sky," said Siemion, who, in addition to his UC Berkeley position, is the Bernard M. Oliver Chair for SETI at the SETI Institute. "This interface will allow us to conduct a powerful, wide-area SETI survey that will be vastly more complete than any previous such search."

"As the VLA conducts its usual scientific observations, this new system will allow for an additional and important use for the data we're already collecting," said NRAO Director Tony Beasley. "Determining whether we are alone in the universe as technologically capable life is among the most compelling questions in science, and NRAO telescopes can play a major role in answering it."

"For the whole of human history, we had a limited amount of data to search for life beyond Earth. So, all we could do was speculate. Now, as we are getting a lot of data, we can do real science and, with making this data available to general public, so can anyone who wants to know the answer to this deep question," said Yuri Milner, the founder of Breakthrough Listen.

Earth transit zone survey

In releasing the new radio and optical data, Siemion highlighted a new analysis of a small subset of the data: radio emissions from 20 nearby stars that are aligned with the plane of Earth's orbit such that an advanced civilization around those stars could see Earth pass in front of the sun (a "transit" like those focused on by NASA's Kepler space telescope). Conducted by the Green Bank Telescope, the Earth transit zone survey observed in the radio frequency range between 4 and 8 gigahertz, the so-called C-band. The data were then analyzed by former UC Berkeley undergraduate Sofia Sheikh, now a graduate student at Pennsylvania State University, who looked for bright emissions at a single radio wavelength or a narrow band around a single wavelength. She has submitted the paper to the Astrophysical Journal.

"This is a unique geometry," Sheikh said. "It is how we discovered other exoplanets, so it kind of makes sense to extrapolate and say that that might be how other intelligent species find planets, as well. This region has been talked about before, but there has never been a targeted search of that region of the sky."

While Sheikh and her team found no technosignatures of civilization, the analysis and other detailed studies the Breakthrough Listen group has conducted are gradually putting limits on the location and capabilities of advanced civilizations that may exist in our galaxy.

"We didn't find any aliens, but we are setting very rigorous limits on the presence of a technologically capable species, with data for the first time in the part of the radio spectrum between 4 and 8 gigahertz," Siemion said. "These results put another rung on the ladder for the next person who comes along and wants to improve on the experiment."

Sheikh noted that her mentor, Jason Wright at Penn State, estimated that if the world's oceans represented every place and wavelength we could search for intelligent signals, we have, to date, explored only a hot tub's worth of it.

"My search was sensitive enough to see a transmitter basically the same as the strongest transmitters we have on Earth, because I looked at nearby targets on purpose," Sheikh said. "So, we know that there isn't anything as strong as our Arecibo telescope beaming something at us. Even though this is a very small project, we are starting to get at new frequencies and new areas of the sky."

Beacons in the galactic center?

The so-far unanalyzed observations from the galactic disk and galactic center survey were a priority for Breakthrough Listen because of the higher likelihood of observing an artificial signal from that region of dense stars. If artificial transmitters are not common in the galaxy, then searching for a strong transmitter among the billions of stars in the disk of our galaxy is the best strategy, Simeon said.

On the other hand, putting a powerful, intergalactic transmitter in the core of our galaxy, perhaps powered by the 4 million-solar-mass black hole there, might not be beyond the capabilities of a very advanced civilization. Galactic centers may be so-called Schelling points: likely places for civilizations to meet up or place beacons, given that they cannot communicate among themselves to agree on a location.

"The galactic center is the subject of a very specific and concerted campaign with all of our facilities because we are in unanimous agreement that that region is the most interesting part of the Milky Way galaxy," Siemion said. "If an advanced civilization anywhere in the Milky Way wanted to put a beacon somewhere, getting back to the Schelling point idea, the galactic center would be a good place to do it. It is extraordinarily energetic, so one could imagine that if an advanced civilization wanted to harness a lot of energy, they might somehow use the supermassive black hole that is at the center of the Milky Way galaxy."

Visit from an interstellar comet

Breakthrough Listen also released observations of the interstellar comet 2I/Borisov, which had a close encounter with the sun in December and is now on its way out of the solar system. The group had earlier scanned the interstellar rock 'Oumuamua, which passed through the center of our solar system in 2017. Neither exhibited technosignatures.

"If interstellar travel is possible, which we don't know, and if other civilizations are out there, which we don't know, and if they are motivated to build an interstellar probe, then some fraction greater than zero of the objects that are out there are artificial interstellar devices," said Steve Croft, a research astronomer with the Berkeley SETI Research Center and Breakthrough Listen. "Just as we do with our measurements of transmitters on extrasolar planets, we want to put a limit on what that number is."

Regardless of the kind of SETI search, Siemion said, Breakthrough Listen looks for electromagnetic radiation that is consistent with a signal that we know technology produces, or some anticipated signal that technology could produce, and inconsistent with the background noise from natural astrophysical events. This also requires eliminating signals from cellphones, satellites, GPS, internet, Wi-fi and myriad other human sources.

In Sheikh's case, she turned the Green Bank telescope on each star for five minutes, pointed away for another five minutes and repeated that twice more. She then threw out any signal that didn't disappear when the telescope pointed away from the star. Ultimately, she whittled an initial 1 million radio spikes down to a couple hundred, which she was able to eliminate as Earth-based human interference. The last four unexplained signals turned out to be from passing satellites.

Siemion emphasized that the Breakthrough Listen team intends to analyze all the data released to date and to do it systematically and often.

Read more at Science Daily

Facial expressions don't tell the whole story of emotion

Interacting with other people is almost always a game of reading cues and volleying back. We think a smile conveys happiness, so we offer a smile in return. We think a frown shows sadness, and maybe we attempt to cheer that person up.

Some businesses are even working on technology to determine customer satisfaction through facial expressions.

But facial expressions might not be reliable indicators of emotion, research indicates. In fact, it might be more accurate to say we should never trust a person's face, new research suggests.

"The question we really asked is: 'Can we truly detect emotion from facial articulations?'" said Aleix Martinez, a professor of electrical and computer engineering at The Ohio State University.

"And the basic conclusion is, no, you can't."

Martinez, whose work has focused on building computer algorithms that analyze facial expressions, and his colleagues presented their findings today (Feb. 16, 2020) at the annual meeting of the American Association for the Advancement of Science in Seattle.

The researchers analyzed the kinetics of muscle movement in the human face and compared those muscle movements with a person's emotions. They found that attempts to detect or define emotions based on a person's facial expressions were almost always wrong.

"Everyone makes different facial expressions based on context and cultural background," Martinez said. "And it's important to realize that not everyone who smiles is happy. Not everyone who is happy smiles. I would even go to the extreme of saying most people who do not smile are not necessarily unhappy. And if you are happy for a whole day, you don't go walking down the street with a smile on your face. You're just happy."

It is also true, Martinez said, that sometimes, people smile out of an obligation to the social norms. This would not inherently be a problem, he said -- people are certainly entitled to put on a smile for the rest of the world -- but some companies have begun developing technology to recognize facial muscle movements and assign emotion or intent to those movements.

The research group that presented at AAAS analyzed some of those technologies and, Martinez said, largely found them lacking.

"Some claim they can detect whether someone is guilty of a crime or not, or whether a student is paying attention in class, or whether a customer is satisfied after a purchase," he said. "What our research showed is that those claims are complete baloney. There's no way you can determine those things. And worse, it can be dangerous."

The danger, Martinez said, lies in the possibility of missing the real emotion or intent in another person, and then making decisions about that person's future or abilities.

For example, consider a classroom environment, and a teacher who assumes that a student is not paying attention because of the expression on the student's face. The teacher might expect the student to smile and nod along if the student is paying attention. But maybe that student, for reasons the teacher doesn't understand -- cultural reasons, perhaps, or contextual ones -- is listening intently, but not smiling at all. It would be, Martinez argues, wrong for the teacher to dismiss that student because of the student's facial expressions.

After analyzing data about facial expressions and emotion, the research team -- which included scientists from Northeastern University, the California Institute of Technology and the University of Wisconsin -- concluded that it takes more than expressions to correctly detect emotion.

Facial color, for example, can help provide clues.

"What we showed is that when you experience emotion, your brain releases peptides -- mostly hormones -- that change the blood flow and blood composition, and because the face is inundated with these peptides, it changes color," Martinez said.

The human body offers other hints, too, he said: body posture, for example. And context plays a crucial role as well.

In one experiment, Martinez showed study participants a picture cropped to display just a man's face. The man's mouth is open in an apparent scream; his face is bright red.

"When people looked at it, they would think, wow, this guy is super annoyed, or really mad at something, that he's angry and shouting," Martinez said. "But when participants saw the whole image, they saw that it was a soccer player who was celebrating a goal."

In context, it's clear the man is very happy. But isolate his face, Martinez said, and he appears almost dangerous.

Cultural biases play a role, too.

"In the U.S., we tend to smile a lot," Martinez said. "We are just being friendly. But in other cultures, that means different things -- in some cultures, if you walked around the supermarket smiling at everyone, you might get smacked."

Martinez said the research group's findings could indicate that people -- from hiring managers to professors to criminal justice experts -- should consider more than just a facial expression when they evaluate another person.

And while Martinez said he is "a big believer" in developing computer algorithms that try to understand social cues and the intent of a person, he added that two things are important to know about that technology.

Read more at Science Daily

The skinny on why poor sleep may increase heart risk in women

Women who sleep poorly tend to overeat and consume a lower-quality diet, according to a new study from researchers at Columbia University Irving Medical Center. The findings provide new insight into how poor sleep quality can increase the risk of heart disease and obesity and points to possible interventions for improving women's heart health.

Previous studies have shown that people who get less sleep are more likely to develop obesity, type 2 diabetes, and heart disease -- and that the relationship may be partially explained by diet. But these studies were narrowly focused on specific foods or nutrients (such as fish, sweets, or saturated fat) or only measured sleep duration, not sleep quality.

The new study was designed to get a more comprehensive picture in women by examining associations between overall diet quality and multiple aspects of sleep quality.

"Women are particularly prone to sleep disturbances across the life span, because they often shoulder the responsibilities of caring for children and family and, later, because of menopausal hormones," says Brooke Aggarwal, EdD, assistant professor of medical sciences at Columbia University Vagelos College of Physicians and Surgeons and senior author of the study.

The study of nearly 500 women was published online today in the Journal of the American Heart Association.

The researchers analyzed the sleep and eating habits of an ethnically diverse group of 495 women, ages 20 to 76. The study looked at sleep quality, the time it took to fall asleep, and insomnia. The women also reported on the types and amounts of foods they typically eat throughout the year, allowing researchers to measure their typical dietary patterns.

Similar to previous studies of sleep and diet, the study found that those with worse overall sleep quality consumed more of the added sugars associated with obesity and diabetes.

Women who took longer to fall asleep had higher caloric intake and ate more food by weight.

And women with more severe insomnia symptoms consumed more food by weight and fewer unsaturated fats than women with milder insomnia.

"Our interpretation is that women with poor-quality sleep could be overeating during subsequent meals and making more unhealthy food choices," says Aggarwal.

The question remains: How might poor sleep contribute to poor eating?

"Poor sleep quality may lead to excessive food and calorie intake by stimulating hunger signals or suppressing signals of fullness," says Faris Zuraikat, PhD, postdoctoral fellow at Columbia University Vagelos College of Physicians and Surgeons and lead author of the study. "Fullness is largely affected by the weight or volume of food consumed, and it could be that women with insomnia consume a greater amount of food in an effort to feel full.

"However, it's also possible that poor diet has a negative impact on women's sleep quality," adds Zuraikat. "Eating more could also cause gastrointestinal discomfort, for instance, making it harder to fall asleep or remain asleep."

"Given that poor diet and overeating may lead to obesity -- a well-established risk factor for heart disease -- future studies should test whether therapies that improve sleep quality can promote cardiometabolic health in women," says Aggarwal.

About the Study

The women in the study were participants in the American Heart Association's Go Red for Women Strategically Focused Research Network at Columbia University Irving Medical Center.

Two other research teams in Columbia's Go Red for Women network are studying the impact of sleep restriction on risk factors for heart disease and on the cells that line blood vessels.

The study is titled "Measures of Poor Sleep Quality Are Associated with Higher Energy Intake and Poor Diet Quality in a Diverse Sample of Women from the Go Red for Women Strategically Focused Research Network."

Read more at Science Daily

States with highest rates of melanoma due to ultraviolet radiation identified

A new study finds a wide state-by-state variation in rates of melanoma caused by ultraviolet (UV) exposure with highest rates in several states on the East and West Coast including Hawaii, but also a few landlocked states, including Utah, Vermont, and Minnesota. The report, appearing in the International Journal of Cancer, finds state-level incidence rates for UV-attributable melanoma ranged from 15 cases per 100,000 in Alaska to 65 cases per 100,000 in Hawaii. The authors say variations between states likely reflect a combination of the strength the sun's rays, participation in outdoor activities, sun protection, indoor tanning, and early detection.

For the new study, investigators led by Farhad Islami, M.D., Ph.D. estimated the number, proportion, and incidence rates of malignant melanomas attributable to UV radiation in each of the United States. They did so by calculating the difference between observed melanomas during 2011-2015 and a baseline of expected cases.

Estimating the contribution of UV exposure required a novel approach. Without a population completely unexposed to UV radiation, researchers used the best data available: historical melanoma incidence rates from 1942-1954 in Connecticut, which had the country's first statewide population-based cancer registry and is in a high-latitude (generally lower UV rate) environment. For most adults, melanomas diagnosed during those years likely reflected UV exposure accumulated in the 1930s or earlier, when exposure was minimized by clothing style with more complete skin coverage and limited recreational exposure. This reference population acted as the theoretical minimum UV exposure.

UV-exposure accounted for 91.0% (338,701/372,335) of the total melanoma cases diagnosed during 2011-2015 in the United States; 94.3% (319,412) of UV-attributable cases occurred in non-Hispanic whites.

To highlight state differences, researchers highlighted results for non-Hispanic whites rather than the total population, because a lower burden in some states could largely reflect higher proportions of non-whites in the population. Melanoma incidence rates in the United States are lowest in blacks (1.0 per 100,000) and are also substantially lower in other minorities (e.g., 4.5 per 100,000 in Hispanics) than in non-Hispanic whites (27.2 per 100,000).

By state, the attributable age-standardized rate among non-Hispanic whites ranged from 15.1 per 100,000 in Alaska to 65.1 in Hawaii. Multiple states along the East and West Coast had UV-attributable incidence rates exceeding 25 per 100,000 among non-Hispanic whites: Delaware (37.1), Georgia (36.5), California (33.8), Maryland (32.6), North Carolina (29.5), Florida (29.2), Oregon (28.5), South Carolina (28.1), Washington (27.8), New Jersey (27.7), New Hampshire (26.5). Rates were also above 25 per 100,000 in Alabama (25.4) and several landlocked states: Utah (40.4), Vermont (31.4), Minnesota (27.9), Idaho (27.6), Kentucky (25.7), and Colorado (24.5).

In addition to states with a high UV index like Hawaii, California, and Florida, UV-attributable melanoma rates are high in many states with relatively low UV index, such as Minnesota and Idaho, likely reflecting high prevalence of outdoor activities (e.g., going to beaches, lakes, or outdoor swimming pools; recreational boating; skiing; and perhaps occupational activities such as farming) and insufficient sun protection. Many UV-related melanomas are preventable using appropriate measures.

Read more at Science Daily

Feb 16, 2020

Computer simulations visualize how DNA converts cells into stem cells

Researchers of the Hubrecht Institute (KNAW -- The Netherlands) and the Max Planck Institute in Münster (Germany) have revealed how an essential protein helps to activate genomic DNA during the conversion of regular adult human cells into stem cells. Their findings are published in the Biophysical Journal.

A cell's identity is driven by which DNA is "read" or "not read" at any point in time. Signalling in the cell to start or stop reading DNA happens through proteins called transcription factors. Identity changes happen naturally during development as cells transition from an undesignated cell to a specific cell type. As it turns out, these transitions can also be reversed. In 2012, Japanese researchers were awarded the Nobel prize for being the first to push a regular skin cell backwards to a stem cell.

A fuller understanding of molecular processes towards stem cell therapies

Until now, it is unknown how the conversion of a skin cell into a stem cell happens exactly, on a molecular scale. "Fully understanding the processes with atomic details is essential if we want to produce such cells for individual patients in the future in a reliable and efficient manner," says research leader Vlad Cojocaru of the Hubrecht Institute. "It is believed that such engineered cell types may in the future be part of the solution to diseases like Alzheimer's and Parkinson's, but the production process would have to become more efficient and predictable."

Pioneer transcription factor

One of the main proteins involved in the stem cell generation is a transcription factor called Oct4. It induces gene expression, or activity, of the proteins that 'reset' the adult cell into a stem cell. Those genes induced are inactive in the adult cells and reside in tightly packed, closed states of chromatin, the structure that stores the DNA in the cell nucleus. Oct4 contributes to the opening of chromatin to allow for the expression of the genes. For this, Oct4 is known as a pioneer transcription factor.

The data from Cojocaru and his PhD candidate -- and first author of the publication -- Jan Huertas show how Oct4 binds to DNA on the so-called nucleosomes, the repetitive nuclear structures in chromatin. Cojocaru: "We modelled Oct4 in different configurations. The molecule consists of two domains, only one of which is able to bind to a specific DNA sequence on the nucleosome in this phase of the process. With our simulations, we discovered which of those configurations are stable and how the dynamics of nucleosomes influence Oct4 binding. The models were validated by experiments performed by our colleagues Caitlin MacCarthy and Hans Schöler in Münster."

One step closer to engineered factors

This is the first time computer simulations show how a pioneer transcription factor binds to nucleosomes to open chromatin and regulate gene expression. "Our computational approach for obtaining the Oct4 models can also be used to screen other transcription factors and to find out how they bind to nucleosomes," Cojocaru says.

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Scientists find ally in fight against brain tumors: Ebola

Brain scan
Glioblastomas are relentless, hard-to-treat, and often lethal brain tumors. Yale scientists have enlisted a most unlikely ally in efforts to treat this form of cancer -- elements of the Ebola virus.

"The irony is that one of the world's deadliest viruses may be useful in treating one of the deadliest of brain cancers," said Yale's Anthony van den Pol, professor of neurosurgery, who describes the Yale efforts Feb. 12 in the Journal of Virology.

The approach takes advantage of a weakness in most cancer tumors and also of an Ebola defense against the immune system response to pathogens.

Unlike normal cells, a large percentage of cancer cells lack the ability to generate an innate immune response against invaders such as viruses. This has led cancer researchers to explore the use of viruses to combat a variety of cancers.

Using viruses carries an obvious risk -- they can introduce potentially dangerous infections. To get around this problem, scientists, including van den Pol, have experimented with creating or testing chimeric viruses, or a combination of genes from multiple viruses. They have the ability to target cancer cells without harming patients.

One of the seven genes of the Ebola virus that helps it avoid an immune system response also contributes to its lethality. This intrigued van den Pol.

He and the study's first author, Xue Zhang, also of Yale, used a chimeric virus containing one of gene from the Ebola virus -- a glycoprotein with a mucin-line domain (MLD). In wild-type Ebola virus, the MLD plays a role in hiding Ebola from the immune system. They injected this chimeric virus into the brains of mice with glioblastoma -- and found that the MLD helped selectively target and kill deadly glioblastoma brain tumors.

(The team worked with the MLD glycoprotein, not with the full Ebola virus.)

Van den Pol said MLD's beneficial effect appears to be that it protects normal cells from infection -- but not cancer cells, which lack the ability to mount an immune response to pathogens.

A key factor may be that the virus with the glycoprotein MLD replicates less rapidly, potentially making it safer than viruses without the MLD part of the glycoprotein, he said.

In theory, such a virus might be used in conjunction with surgery to eliminate glioblastoma tumors and help prevent a recurrence of cancer, he said.

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