Culture

Warm, cold, just right? Physicists at the University of California, Davis are taking the temperature of dark matter, the mysterious substance that makes up about a quarter of our universe.

We have very little idea of what dark matter is and physicists have yet to detect a dark matter particle. But we do know that the gravity of clumps of dark matter can distort light from distant objects. Chris Fassnacht, a physics professor at UC Davis and colleagues are using this distortion, called gravitational lensing, to learn more about the properties of dark matter.

The standard model for dark matter is that it is 'cold,' meaning that the particles move slowly compared to the speed of light, Fassnacht said. This is also tied to the mass of dark matter particles. The lower the mass of the particle, the 'warmer' it is and the faster it will move.

The model of cold (more massive) dark matter holds at very large scales, Fassnacht said, but doesn't work so well on the scale of individual galaxies. That's led to other models including 'warm' dark matter with lighter, faster-moving particles. 'Hot' dark matter with particles moving close to the speed of light has been ruled out by observations.

Former UC Davis graduate student Jen-Wei Hsueh, Fassnacht and colleagues used gravitational lensing to put a limit on the warmth and therefore the mass of dark matter. They measured the brightness of seven distant gravitationally lensed quasars to look for changes caused by additional intervening blobs of dark matter and used these results to measure the size of these dark matter lenses.

If dark matter particles are lighter, warmer and more rapidly-moving, then they will not form structures below a certain size, Fassnacht said.

"Below a certain size, they would just get smeared out," he said.

The results put a lower limit on the mass of a potential dark matter particle while not ruling out cold dark matter, he said. The team's results represent a major improvement over a previous analysis, from 2002, and are comparable to recent results from a team at UCLA.

Fassnacht hopes to continue adding lensed objects to the survey to improve the statistical accuracy.

"We need to look at about 50 objects to get a good constraint on how warm dark matter can be," he said.

Québec, January 15 2020 -- Atrazine is one of the most widely used pesticides in North America. Researchers at the Institut National de la Recherche Scientifique (INRS) have developed a new method to degrade it that combines a new nanostructured material and sunlight.

Atrazine is found throughout the environment, even in the drinking water of millions of people across the country. Conventional water treatments are not effective in degrading this pesticide. Newer processes are more effective, but use chemicals that can leave toxic by-products in the environment.

Professor My Ali El Khakani, an expert in nanostructured materials, and Professor Patrick Drogui, a specialist in electrotechnology and water treatment, have joined forces to develop a new ecological degradation process for atrazine that is as chemical-free as possible. "By working synergistically, we were able to develop a water treatment process that we would never have been able to achieve separately. This is one of the great added values of inter disciplinarity in research," says Professor El Khakani, lead author of the study, whose results are published today in the journal Catalysis Today.

The researchers use an existing process, called photoelectro-catalysis or PEC, which they have optimized for the degradation of atrazine. The process works with two photoelectrodes (light-sensitive electrodes) of opposite charges. Under the effect of light and an electrical potential, it generates free radicals on the surface of the photoelectrodes. Those radicals interact with atrazine molecules and degrade them. "The use of free radicals is advantageous because it does not leave toxic by-products as chlorine would do. They are highly reactive and unstable. As their lifetime is very short they tend to disappear quickly," explains Professor Drogui, who is a co-author of the study.

The materials' challenges

To make photoelectrodes (light-sensitive electrodes), Professor El Khakani has chosen titanium oxide (TiO2), a material that is very abundant, chemically stable, and used in many applications including white pigment in paints or sunscreens. Usually, this semiconducting material converts the light energy provided by UV rays into active charges. In order to take advantage of the entire solar spectrum, i.e. visible light in addition to UV, Professor El Khakani had to make the TiO2 films sensitive to visible sunlight. To this end, his team modified titanium oxide on an atomic scale by incorporating nitrogen and tungsten atoms using a plasma process. This doping reduces the photon energy required to trigger PEC in these novel photoelectrodes.

Since the PEC process is genuinely a surface phenomenon, the treatment of a large volume requires a large surface area of the photoelectrodes. For this, Professor El Khakani's team exploited to the advantages of nanostructuring the surface of photoelectrodes. "Instead of having a flat surface, imagine sculpting it on the nanoscale to create valleys and mountains. This increases the active surface available without changing the physical surface. This is called nanostructuring. Thus, the active surface is artificially increased by several thousand times compared to the physical surface. With 1 g of material, active surface areas between 50 and 100 m2 can be achieved--that's about the surface of an apartment!", says Professor El Khakani.

New process efficiency and its limits

Once the photoelectrodes were developed and integrated into a PEC reactor, Professor Drogui's team optimized the process. His team first used samples of demineralized water to which atrazine was added. PEC with the photoelectrode eliminated about 60 percent of the pesticide after 300 minutes of treatment. Researchers then moved on to real samples of water collected from the Nicolet River (QC, Canada) near areas of intensive corn and soybean agricultures where herbicides are often used.

When using actual water samples, only 8 percent of the atrazine was degraded initially. This low percentage is due to the presence of suspended particles that prevent much of the light from reaching the photoelectrode. In addition, the species present in the solution can attach to the electrode thus reducing its active area. Capitalizing on its expertise in water decontamination, Professor Drogui's team carried out pretreatments based on coagulation and filtration of certain species before applying the PEC approach again. They then succeeded in degrading 38 to 40 percent of atrazine in the real samples.

The treatment efficiency remains relatively low compared to synthetic water because real water contains bicarbonates and phosphates that trap free radicals and prevent them from reacting with atrazine. "Pre-treatment by chemical coagulation helps remove phosphates, but not bicarbonates. Calcium could be added to precipitate them, but we want to minimize the use of chemicals," says Professor Drogui.

According to the authors, their new optimized PEC could be used as a tertiary treatment, after removing suspended particles and coagulable species. However, a pre-industrial demonstration stage is required before thinking about large-scale use. Finally, their process has been used to degrade atrazine, but the two teams continue to work together to address other emerging pollutants and antibiotic residues in water.

A new paper in Nutrition Reviews finds that intake of the flavonoid quercetin can greatly reduce high blood pressure in patients suffering from cardiovascular disease.

Researchers here consulted multiple studies that assessed the impact of quercetin on blood pressure and glucose levels. Quercetin is a plant pigment commonly found in many plants and foods, such as onions, teas, apples and red wine. Each study utilized here assessed blood glucose, total cholesterol, and/or insulin. 17 studies with a total of 886 participants were included.

The pooled result from 13 treatment arms throughout the studies consulted showed that quercetin administration markedly reduced systolic blood pressure. Participants who consumed quercetin for eight weeks or more showed significantly changed levels of high-density lipoprotein cholesterol. Quercetin did not markedly influence total cholesterol, or significantly alter fasting blood glucose concentrations. Quercetin was not found to cause serious adverse events in any of the included studies.

The review concluded that a reduction in blood pressure of more than 10 mmHg lowers cardiovascular risk by 50% for heart failure, 35% - 40% for stroke, and approximately 20% to 25% for myocardial infarction. Researchers here found that the favorable effects of quercetin on blood pressure support the use of quercetin for patients with hypertension.

AUSTIN, Texas--A new study by the Texas Policy Evaluation Project (TxPEP) finds that approximately seven percent of patients seeking abortion at Texas clinics had tried to end their current pregnancy on their own before coming to the clinic. This is higher than the national rate of 2.2 percent. The article was recently published in BMC Women's Health.

Women mentioned four primary reasons for attempting to self-manage their abortion: 1) they could not afford to get to a clinic or pay for the procedure; 2) their local clinic had closed; 3) a close friend or family member recommended self-managing abortion and 4) they wanted to avoid the stigma or shame of having an abortion.

"No single reason was enough for anyone to consider self-managing their abortion," says Liza Fuentes, senior research scientist at Guttmacher Institute and researcher with TxPEP at the time of the study. "For all of the women we interviewed, poverty intersected with other obstacles to leave them feeling they had no other option."

The methods used for abortion self-management fell into two broad categories: medications, such as misoprostol, a safe and effective pill used as part of clinic-based medication abortions that can be obtained in Mexico without a prescription; and home remedies such as herbs, teas, and vitamins. Most women who used misoprostol were successful in ending their pregnancy; women who used home remedies did so without success and then sought abortion care at a clinic.

Nearly all of the women in the study said that they would prefer to go to a clinic and would recommend a friend go to a clinic instead of trying to self-manage their abortion because their experience was difficult, painful, uncomfortable, or because it could be dangerous or ineffective.

"Even though the women we interviewed said they would prefer going to a clinic, many chose self-managed abortion when that was the only feasible option," says Daniel Grossman, investigator at TxPEP and director of Advancing New Standards in Reproductive Health at the University of California at San Francisco. "These findings highlight how barriers to care force some people to self-manage their abortion when faced with limited options."

These results are based on 721 surveys conducted in 2012 and 2014 with patients seeking abortion care at facilities in Texas and 18 interviews conducted from October 2014-October 2015 with women in Texas, some of whom did not access clinic-based care, about their experiences with self-managed abortion.

Since 2011, Texas has passed numerous laws limiting access to clinic-based abortion services. These laws include a mandatory ultrasound requirement, stricter gestational age limits for abortion, and other medically unnecessary restrictions on abortion providers and facilities. There currently are only 24 facilities providing abortion services in the state of Texas, compared to 41 clinics that were open in 2012.

When you expect a really bad experience to happen and then it doesn't, it's a distinctly positive feeling. A new study of fear extinction training in mice may suggest why: The findings not only identify the exact population of brain cells that are key for learning not to feel afraid anymore, but also show these neurons are the same ones that help encode feelings of reward.

The study, published Jan. 14 in Neuron by scientists at MIT's Picower Institute for Learning and Memory, specifically shows that fear extinction memories and feelings of reward alike are stored by neurons that express the gene Ppp1r1b in the posterior of the basolateral amygdala (pBLA), a region known to assign associations of aversive or rewarding feelings, or "valence," with memories. The study was conducted by Xiangyu Zhang, a graduate student, Joshua Kim, a former graduate student, and Susumu Tonegawa, Professor of Biology and Neuroscience at RIKEN-MIT Laboratory of Neural Circuit Genetics at the Picower Institute for Learning and Memory at MIT and Howard Hughes Medical Institute.

"We constantly live at the balance of positive and negative emotion," Tonegawa said. "We need to have very strong memories of dangerous circumstances in order to avoid similar circumstances to recur. But if we are constantly feeling threatened we can become depressed. You need a way to bring your emotional state back to something more positive."

Overriding fear with reward

In a prior study, Kim showed that Ppp1r1b-expressing neurons encode rewarding valence and compete with distinct Rspo2-expressing neurons in the BLA that encode negative valence. In the new study, Zhang, Kim and Tonegawa set out to determine whether this competitive balance also underlies fear and its extinction.

In fear extinction, an original fearful memory is thought to be essentially overwritten by a new memory that is not fearful. In the study, for instance, mice were exposed to little shocks in a chamber, making them freeze due to the formation of fearful memory. But the next day, when the mice were returned to the same chamber for a longer period of time without any further little shocks, freezing gradually dissipated and hence this treatment is called fear extinction training. The fundamental question then is whether the fearful memory is lost or just suppressed by the formation of a new memory during the fear extinction training.

While the mice underwent fear extinction training the scientists watched the activity of the different neural populations in the BLA. They saw that Ppp1r1b cells were more active and Rspo2 cells were less active in mice that experienced fear extinction. They also saw that while Rspo2 cells were mostly activated by the shocks and were inhibited during fear extinction, Ppp1r1b cells were mostly active during extinction memory training and retrieval, but were inhibited during the shocks.

These and other experiments suggested to the authors that the hypothetical fear extinction memory may be formed in the Ppp1r1b neuronal population and the team went on to demonstrate this vigorously. For this, they employed the technique previously pioneered in their lab for the identification and manipulation of the neuronal population that holds specific memory information, memory "engram" cells. Zhang labeled Ppp1r1b neurons that were activated during retrieval of fear extinction memory with the light-sensitive protein channelrhodopsin. When these neurons were activated by blue laser light during a second round of fear extinction training it enhanced and accelerated the extinction. Moreover, when the engram cells were inhibited by another optogenetic technique, fear extinction was impaired because the Ppp1r1b engram neurons could no longer suppress the Rspo2 fear neurons. That allowed the fear memory to regain primacy.

These data met the fundamental criteria for the existence of engram cells for fear extinction memory within the pBLA Ppp1r1b cell population: activation and reactivation by recall and enduring and off-line maintenance of the acquired extinction memory.

Because Kim had previously shown Ppp1r1b neurons are activated by rewards and drive appetitive behavior and memory, the team sequentially tracked Ppp1r1b cell activity in mice that eagerly received water reward followed by food reward followed by fear extinction training and fear extinction memory retrieval. The overlap of Ppp1r1b neurons activated by fear extinction vs. water reward was as high as the overlap of neurons activated by water vs. food reward. And finally, artificial optogenetic activation of Ppp1r1b extinction memory engram cells was as effective as optogenetic activation of Ppp1r1b water reward-activated neurons in driving appetitive behaviors. Reciprocally, artificial optogenetic activation of water-responding Ppp1r1b neurons enhanced fear extinction training as efficiently as optogenetic activation of fear extinction memory engram cells. These results demonstrate that fear extinction is equivalent to bona fide rewards and therefore provide the neuroscientific basis for the widely held experience in daily life: omission of expected punishment is a reward.

What next?

By establishing this intimate connection between fear extinction and reward and by identifying a genetically defined neuronal population (Ppp1r1b) that plays a crucial role in fear extinction this study provides potential therapeutic targets for treating fear disorders like PTSD and anxiety, Zhang said.

From the basic scientific point of view, Tonegawa said, how fear extinction training specifically activates Ppp1r1b neurons would be an important question to address. More imaginatively, results showing how Ppp1r1b neurons override Rspo2 neurons in fear extinction raises an intriguing question about whether a reciprocal dynamic might also occur in the brain and behavior. Investigating "joy extinction" via these mechanisms might be an interesting research topic.

SAN DIEGO, Calif.--A new species of feathered dinosaur has been discovered in China, and described by American and Chinese authors and published today in the journal, The Anatomical Record.

The one-of-a-kind specimen offers a window into what the earth was like 120 million years ago. The fossil preserves feathers and bones that provide new information about how dinosaurs grew and how they differed from birds.

"The new dinosaur fits in with an incredible radiation of feathered, winged animals that are closely related to the origin of birds," said Dr. Ashley Poust, who analyzed the specimens while he was a student at Montana State University and during his time as a Ph.D. student at University of California, Berkeley. Poust is now postdoctoral researcher at the San Diego Natural History Museum.

"Studying specimens like this not only shows us the sometimes-surprising paths that ancient life has taken, but also allows us to test ideas about how important bird characteristics, including flight, arose in the distant past."

Scientists named the dinosaur Wulong bohaiensis. Wulong is Chinese for "the dancing dragon" and references the position of the beautifully articulated specimen.

About the Discovery

The specimen was found more than a decade ago by a farmer in China, in the fossil-rich Jehol Province, and since then has been housed in the collection of The Dalian Natural History Museum in Liaoning, a northeastern Chinese province bordering North Korea and the Yellow Sea. The skeletal bones were analyzed by Poust alongside his advisor Dr. David Varricchio from Montana State University while Poust was a student there.

Larger than a common crow and smaller than a raven, but with a long, bony tail which would have doubled its length, Wulong bohaiensis had a narrow face filled with sharp teeth. Its bones were thin and small, and the animal was covered with feathers, including a wing-like array on both its arms and legs and two long plumes at the end of its tail.

This animal is one of the earliest relatives of Velociraptor, the famous dromaeosaurid theropod dinosaur that lived approximately 75 million years ago. Wulong's closest well-known relative would have been Microraptor, a genus of small, four-winged paravian dinosaurs.

The discovery is significant not only because it describes a dinosaur that is new to science, but also because it shows connection between birds and dinosaurs.

"The specimen has feathers on its limbs and tail that we associate with adult birds, but it had other features that made us think it was a juvenile," said Poust. To understand this contradiction, the scientists cut up several bones of the new dinosaur to examine under a microscope. This technique, called bone histology, is becoming a regular part of the paleontology toolbox, but it's still sometimes difficult to convince museums to let a researcher remove part of a nice skeleton. "Thankfully, our coauthors at the Dalian Natural History Museum were really forward thinking and allowed us to apply these techniques, not only to Wulong, but also to another dinosaur, a close relative that looked more adult called Sinornithosaurus."

The bones showed that the new dinosaur was a juvenile. This means that at least some dinosaurs were getting very mature looking feathers well before they were done growing. Birds grow up very fast and often don't get their adult plumage until well after they are full sized. Showy feathers, especially those used for mating, are particularly delayed. And yet here was an immature dinosaur with two long feathers extending beyond the tip of the tail.

"Either the young dinosaurs needed these tail feathers for some function we don't know about, or they were growing their feathers really differently from most living birds," explained Poust.

An additional surprise came from the second dinosaur the scientists sampled; Sinornithosaurus wasn't done growing either. The bone tissue was that of an actively growing animal and it lacked an External Fundamental System: a structure on the outside of the bone that vertebrates form when they're full size. "Here was an animal that was large and had adult looking bones: we thought it was going to be mature, but histology proved that idea wrong. It was older than Wulong, but seems to have been still growing. Researchers need to be really careful about determining whether a specimen is adult or not. Until we learn a lot more, histology is really the most dependable way."

In spite of these cautions, Poust says there is a lot more to learn about dinosaurs.

"We're talking about animals that lived twice as long ago as T. rex, so it's pretty amazing how well preserved they are. It's really very exciting to see inside these animals for the first time."

About the Jehol Biota

The area in which the specimen was found is one of the richest fossil deposits in the world. The Jehol biota is known for the incredible variety of animals that were alive at the time. It is also one of the earliest bird-rich environments, where birds, bird-like dinosaurs, and pterosaurs all shared the same habitat.

"There was a lot of flying, gliding, and flapping around these ancient lakes," says Poust. "As we continue to discover more about the diversity of these small animals it becomes interesting how they all might have fit into the ecosystem." Other important changes were happening at the same time in the Early Cretaceous, including the spread of flowering plants. "It was an alien world, but with some of the earliest feathers and earliest flowers, it would have been a pretty one."

Each year, more than 6,500 cases of bladder cancer--nearly 5% of all cases in Europe-- can be attributed to exposure to trihalomethanes (THMs) in drinking water. This is one of the conclusions of a large-scale study led by the Barcelona Institute for Global Health (ISGlobal), a centre supported by "la Caixa", that analysed for the first time the presence of these chemical compounds in the tap water of 26 European Union countries.

Trihalomethanes are formed as an unintended consequence of water disinfection. Earlier research has found an association between long-term exposure to THMs--whether through ingestion, inhalation or dermal absorption--and increased risk of bladder cancer.

The authors of the new study, published in Environmental Health Perspectives, analysed recent data on trihalomethanes levels in European municipal tap water and estimated the burden of disease for bladder cancer attributable to exposure to these compounds.

"The biggest challenge was collecting representative data on national trihalomethanes levels for all EU countries", explained Cristina Villanueva, the ISGlobal researcher who coordinated the study. "We hope that these data will become more readily available in the future."

The researchers sent questionnaires to bodies responsible for municipal water quality requesting information on the concentration of total and individual trihalomethanes (chloroform, bromodichloromethane, dibromochloromethane, and bromoform) at the tap, in the distribution network and at water treatment plants. Complementary data was obtained from other sources ¬(open data online, reports, scientific literature, etc.).

Trihalomethanes data for 2005 to 2018 were obtained for 26 European Union countries--all except Bulgaria and Romania, where less information was available--covering 75% of the population.

The findings revealed considerable differences between countries. The average level of trihalomethanes in drinking water in all countries was well below the maximum permissible limit in the EU--11.7 μg/L versus 100 μg/L-- but the maximum reported concentrations did exceed the limit in nine countries (Cyprus, Estonia, Hungary, Ireland, Italy, Poland, Portugal, Spain and the United Kingdom).

Lead author Iro Evlampidou described the study as being "of particular interest to countries with high average levels of trihalomethanes concentrations recorded in tap water."

Association with Bladder Cancer

The number of attributable bladder cancer cases was estimated through a statistical calculation linking average levels of trihalomethanes with the international information available of bladder cancer incidence rates for each country.

In total, the researchers estimated that 6,561 bladder cancer cases per year are attributable to trihalomethanes exposure in the European Union. Considerable differences were found between countries. Spain and the United Kingdom had the largest number of attributable cases of bladder cancer--1,482 and 1,356, respectively--due in part to the high incidence of bladder cancer and their large population.

The countries with the highest percentage of bladder cancer cases attributable to THM exposure were Cyprus (23%), Malta (17%), Ireland (17%), Spain (11%) and Greece (10%). At the opposite extreme, there were Denmark (0%), Netherlands (0.1%), Germany (0.2%), Austria (0.4%) and Lithuania (0.4%).

"Over the past 20 years, major efforts have been made to reduce trihalomethanes levels in several countries of the European Union, including Spain", commented ISGlobal researcher Manolis Kogevinas. "However, the current levels in certain countries could still lead to considerable bladder cancer burden, which could be prevented by optimising water treatment, disinfection and distribution practices and other measures."

The authors of the study recommended that efforts to reduce trihalomethanes levels should focus on countries with the highest average levels. If the 13 countries with the highest averages were to reduce their THM levels to the EU average, the researchers estimate that 2,868 annual attributable bladder cancer cases--44% of the total-- could potentially be avoided.

Phosphorus, present in our DNA and cell membranes, is an essential element for life as we know it. But how it arrived on the early Earth is something of a mystery. Astronomers have now traced the journey of phosphorus from star-forming regions to comets using the combined powers of ALMA and the European Space Agency's probe Rosetta. Their research shows, for the first time, where molecules containing phosphorus form, how this element is carried in comets, and how a particular molecule may have played a crucial role in starting life on our planet.

"Life appeared on Earth about 4 billion years ago, but we still do not know the processes that made it possible," says Víctor Rivilla, the lead author of a new study published today in the journal Monthly Notices of the Royal Astronomical Society. The new results from the Atacama Large Millimeter/Submillimeter Array (ALMA), in which the European Southern Observatory (ESO) is a partner, and from the ROSINA instrument on board Rosetta, show that phosphorus monoxide is a key piece in the origin-of-life puzzle.

With the power of ALMA, which allowed a detailed look into the star-forming region AFGL 5142, astronomers could pinpoint where phosphorus-bearing molecules, like phosphorus monoxide, form. New stars and planetary systems arise in cloud-like regions of gas and dust in between stars, making these interstellar clouds the ideal places to start the search for life's building blocks.

The ALMA observations showed that phosphorus-bearing molecules are created as massive stars are formed. Flows of gas from young massive stars open up cavities in interstellar clouds. Molecules containing phosphorus form on the cavity walls, through the combined action of shocks and radiation from the infant star. The astronomers have also shown that phosphorus monoxide is the most abundant phosphorus-bearing molecule in the cavity walls.

After searching for this molecule in star-forming regions with ALMA, the European team moved on to a Solar System object: the now-famous comet 67P/Churyumov-Gerasimenko. The idea was to follow the trail of these phosphorus-bearing compounds. If the cavity walls collapse to form a star, particularly a less-massive one like the Sun, phosphorus monoxide can freeze out and get trapped in the icy dust grains that remain around the new star. Even before the star is fully formed, those dust grains come together to form pebbles, rocks and ultimately comets, which become transporters of phosphorus monoxide.

ROSINA, which stands for Rosetta Orbiter Spectrometer for Ion and Neutral Analysis, collected data from 67P for two years as Rosetta orbited the comet. Astronomers had found hints of phosphorus in the ROSINA data before, but they did not know what molecule had carried it there. Kathrin Altwegg, the Principal Investigator for Rosina and an author in the new study, got a clue about what this molecule could be after being approached at a conference by an astronomer studying star-forming regions with ALMA: "She said that phosphorus monoxide would be a very likely candidate, so I went back to our data and there it was!"

This first sighting of phosphorus monoxide on a comet helps astronomers draw a connection between star-forming regions, where the molecule is created, all the way to Earth.

"The combination of the ALMA and ROSINA data has revealed a sort of chemical thread during the whole process of star formation, in which phosphorus monoxide plays the dominant role," says Rivilla, who is a researcher at the Arcetri Astrophysical Observatory of INAF, Italy's National Institute for Astrophysics.

"Phosphorus is essential for life as we know it," adds Altwegg. "As comets most probably delivered large amounts of organic compounds to the Earth, the phosphorus monoxide found in comet 67P may strengthen the link between comets and life on Earth."

This intriguing journey could be documented because of the collaborative efforts between astronomers. "The detection of phosphorus monoxide was clearly thanks to an interdisciplinary exchange between telescopes on Earth and instruments in space," says Altwegg.

Leonardo Testi, ESO astronomer and ALMA European Operations Manager, concludes: "Understanding our cosmic origins, including how common the chemical conditions favourable for the emergence of life are, is a major topic of modern astrophysics. While ESO and ALMA focus on the observations of molecules in distant young planetary systems, the direct exploration of the chemical inventory within our Solar System is made possible by ESA missions, like Rosetta. The synergy between world leading ground-based and space facilities, through the collaboration between ESO and ESA, is a powerful asset for European researchers and enables transformational discoveries like the one reported in this paper."

The future potential of early stage startups can be assessed by their existing professional relationships, research led by a team at Queen Mary University of London suggests.

Using available online data from 41,380 companies collected over 25 years, the research team created a visual network to show connections between companies and their employees.

They found that young startups who quickly acquire a central position within the network are more likely to show signs of long-term economic success.

The team then used this approach to develop success prediction algorithms, which were shown to be two to three times more accurate when predicting future economic performance than current labour-intensive screening methods adopted by venture capital firms.

The findings are published today in Scientific Reports.

Startups were ranked based on their values of 'closeness centrality', which measures the average distance of one company from other firms within the network. Results indicate the predictive link between rankings and long term success, with 30% of the top 20 firms each month achieving a positive economic outcome within seven years.

The researchers were able to validate their approach by reviewing the rankings of well-known successful companies such as Facebook, Uber and Airbnb over time. They discovered that these companies swiftly moved to high ranking positions soon after they were founded.

Data used in the study was collated from the online source crunchbase.com and information on funding rounds, acquisitions and initial public offerings (IPO) were all used as measures of startup success.

Dr Moreno Bonaventura, former PhD student at Queen Mary and Chief Scientist at Startup-Network.org, said: "The people within a company, be it investors, employees or advisors, bring with them experience from other firms on effective strategies, know-how on cutting-edge technologies, and their own personal contacts. Global networks are the backbone through which knowledge is gained and shared, and this information can be used to build predictive intelligence on the future economic performance of young companies."

Dr Lucas Lacasa, Reader in Applied Mathematics and Engineering and Physical Sciences Research Council (EPSRC) Early Career Fellow at Queen Mary, said: "Traditionally historic reports on sales, growth or market size are used to predict future success but with startups this level of data usually isn't available. Instead measures such as the qualifications and attributes of founding entrepreneurs are used, which can be subjective as well as labour-intensive. We propose that this novel, data-driven approach could complement existing screening approaches used by investors and we anticipate that further refinements could improve the prediction accuracy even more."

(New York, NY - January 15, 2020) - Many liver cancer tumors contain a highly diverse set of cells, a phenomenon known as intra-tumor heterogeneity that can significantly affect the rate at which the cancer grows, Mount Sinai researchers report. The immune system's contribution to this heterogeneity can have major clinical implications.

In a study published in January in Nature Communications, the team reported that this heterogeneity--either within the same tumor or between different tumor regions in the same tumor nodule--appears in about 30 percent of patients with hepatocellular cancer (HCC), the most common form of liver cancer, and that some of these tumors grow rapidly by hijacking different gene networks.

"Tumors are a complex ecosystem, and we're developing for the first time a blueprint of the different ways they can evolve in patients with liver cancer by interacting with the immune system," says Augusto Villanueva, MD, PhD, Assistant Professor in the Liver Cancer Program at The Tisch Cancer Institute at Mount Sinai, and corresponding author of the study. "By better understanding how tumors progress, we're learning more about how they adapt to pharmacological pressures, and how they can develop mechanisms of resistance to cancer therapies. This greater awareness will hopefully lead to the identification of biomarkers that can predict which patients will be responsive to treatment."

Among the clinical implications associated with intra-tumor heterogeneity identified by the research team was the discovery that a single liver cancer biopsy could potentially mischaracterize a liver tumor.

"Some tumors are very homogeneous in terms of their genetic makeup and immune cell infiltration, while others are very heterogeneous," says Dr. Villanueva. "This means that a biopsy from the same tumor could yield different information depending on where it was taken, and could thus affect clinical decision-making for the patient. That's why our work aimed at learning how tumors evolve and the different trajectories they can take is so important to future cancer research, as well as to effectively treating the disease."

As immunotherapy continues to transform cancer research and treatment, one of the most promising areas is liver cancer, which has become the fastest-rising malignancy in the United States in terms of incidence and mortality, responsible for 33,000 new cases annually. Two phase 2 clinical trials using PD-1 immune checkpoint inhibitors, which help the body's immune system recognize and attack cancerous cells, have achieved unprecedented responses in humans, prompting the Food and Drug Administration to grant them accelerated approval status for second-line treatment of advanced hepatocellular cancer.

More recently, a phase 3 clinical trial combining a PD-1 immune checkpoint inhibitor with an antiangiogenic improved survival compared to the current first-line standard of care, sorafenib. Still, only about 30 percent of patients with HCC are believed to respond favorably to immune checkpoint inhibition--an outcome not uncommon with immunotherapies.

"The immune system imposes significant constraints on liver cancer evolution, and by investigating the interaction of immune cells and cancer cells at the molecular level we're trying to predict or anticipate mechanisms of tumor resistance," explains Bojan Losic, PhD, Associate Professor of Genetics and Genomic Sciences, Cancer Immunology Program, at Icahn School of Medicine at Mount Sinai, and lead author of the study. "Our work is particularly relevant considering the remarkable success of immune checkpoint inhibitors in some heterogeneous solid tumors."

To understand the mechanisms that drive tumor progression on a patient-by-patient basis, the research team from Mount Sinai and other medical centers around the world performed an integrated molecular analysis of gene expression, immune activities, and DNA mutations from multiple regions of the same tumor nodule in 14 liver cancer patients. The study was the first to use single-cell RNA sequencing in multiple regions of the same tumor nodule, and was among the first to assess the contribution of the immune system to liver cancer evolution.

Chinese scientists have recently shown how the tiny apex structure in plant leaves controls water drainage and confers an evolutionary advantage.

The research was conducted by Prof. JIANG Lei's team at the Technical Institute of Physical Chemistry of the Chinese Academy of Sciences. Results were published online in PNAS Jan. 13.

The leaf is the basis of plant survival. Through evolution, leaves have developed means to help control the absorption of sunshine and rain. The apex, for example, is where water is shed from the leaf and thus affects how droplets are shed.

In rainforests - which are characterized by high precipitation and humidity - understory plant leaves must drain water fast to avoid water-induced rot and damage. The most famous evolutionary advance in rainforest leaves is the drip tip. Although biologists have known since the 1980s that the drip tip facilitates fast drainage, they didn't understand the role the apex played in this process.

According to Dr. DONG Zhichao, the study's corresponding author, the tapered shape of the apex causes reduced capillary resistance in droplets. At the same time, the steep orientation of the apex increases the effect of gravity. Together, the apex's shape and orientation increase instability, thus enhancing water drainage.

For DONG, understanding this mechanism not only increases our appreciation of the role tiny structures play in plant survival, but also provides inspiration for upgrading drainage facilities and anticorrosion architecture.

This is especially important since dripping modes characterized by high frequency, low retention and low volume help reduce soil erosion.

Ancient architects intuitively understood the efficiency of drip tips, since drip tiles in oriental palace roofs and gargoyles in cathedrals exhibit excellent drainage and anticorrosion ability.

AURORA, Colo. (Jan. 15, 2020) - A byproduct of glucose called lactate, used by every cell in the body, may also prompt a mutated cell to become cancerous, according to new research from the University of Colorado Anschutz Medical Campus.

The study was published Tuesday in the journal Frontiers in Oncology.

"We discovered that lactate is a catalyst that triggers a mechanism in mutated cells necessary to continue the cancer forming process," said Iñigo San Millán, assistant professor of medicine at the University of Colorado School of Medicine and the University of Colorado Colorado Springs. "This opens a new door to better understand cancer at the metabolic level. It also means we might be able to target lactate with new therapies."

Lactate is not a waste product but a major source of energy for the cell, especially the mitochondria.

The role of lactate in cancer was first described nearly a century ago when Nobel Laureate Otto Warburg discovered that cancer cells were characterized not only by how quickly they consumed glucose, but a marked increase in lactate production. The process was called `The Warburg Effect.'

But exactly how it worked remained a mystery. In 2017, San Millán and his colleague from the University of California, Berkeley, George Brooks, PhD, published a hypothesis they believe explained for the first time the meaning and purpose of the Warburg Effect - to produce lactate for cancer formation purposes.

San Millán, who specializes in metabolism, and his team, sought to demonstrate this hypothesis. They exposed human breast cancer cells to glucose which then produced lactate. The lactate increased the expression of all the main mutated genes involved in breast cancer between 150-800%.

It's well known that not every mutated cell becomes cancerous and there has been speculation on what factors might `trigger' the expression of mutated genes. This study demonstrates that lactate is a key trigger. Now, San Millán and his team are reproducing this study in other cancers like small-cell lung cancer and non-small-cell lung cancer and finding similar results.

"Lactate, which used to be considered a waste product, turns out to be a major signaling molecule and a major regulator of the genes involved in cancer," San Millán said. "This is not the same behavior of lactate we get from doing exercise because that is quickly removed by the muscles and has positive signaling properties to improve physical fitness. The lactate produced in cancer stays put, is constantly being produced and acts as a catalyst to activate mutated genes into cancer. We still don't know these mechanisms but we are investigating them now."

Human muscle tissue is largely resistant to the formation of cancer. Exercise actually reduces the risks of some cancers and even could treat them therapeutically. San Millán has already started applying personalized exercise programs to cancer patients as part of their cancer rehabilitation and is exploring mechanisms by which exercise can help prevent and treat cancer.

He's also trying to find ways to block lactate from leaving the cancer cell.

"When lactate is produced it has to leave the cell through a transporter," he said. "We are trying to block the transporter as well as lactate production inside the cancer cell with different compounds. If you block the door, the lactate cannot leave and the cancer cell will burst."

But trying to block lactate in a human with a systemic drug would be deadly, so more targeted treatments are called for.

Furthermore, lactate from cancer cells seems to be a key player in keeping the immune system from attacking cancer cells, which is a typical characteristic of cancer.

San Millán and his team are currently doing trying to block lactate in different cancers implanted in mice.

"If we can effectively target lactate," he said. "We could possibly be taking a great step toward ending cancer."

La Trobe University researchers have found introducing a minimum unit price (MUP) of $1.30 per standard drink across Australia could dramatically reduce alcohol consumption.

Such a policy, already proven successful in Canada and Eastern Europe, could reduce drinking in Australia by 1.5 standard drinks per week on average and 12 drinks per week for harmful drinkers.

La Trobe Centre for Alcohol Policy Research (CAPR) health economist Dr Jason (Heng) Jiang said alcohol affordability in Australia has remained relatively unchanged over the last 30 years.

"In contrast, alcohol-related hospitalisations, emergency department and ambulance presentations, assaults and community-based specialised drug and alcohol treatment episodes have steadily increased in Australia."

On average, Australian drinkers consumed 14 standard drinks per week. Compared with moderate drinkers, harmful drinkers consumed a 17 times greater amount of alcohol per week (4.6 vs 80.7 standard drinks).

Average weekly alcohol spending by harmful drinkers was 11 times higher than spending by moderate drinkers ($178.40 vs $20.90). CAPR researchers also found 62 per cent of alcohol consumed by Australian drinkers was retail/take-away regular beer and bottle wine.

Dr Jiang analysed 2013 survey data of 1,789 Australian adults to reveal, for the first time, the effects of pricing policy initiatives on alcohol consumption in different drinking, income and age subpopulation groups.

"Minimum unit price policies primarily affect prices of low-cost beverages, nearly always sold off-premise, while a uniform excise tax would increase prices of almost all on- and off-sale beverages substantially, though with a smaller impact on spirits," Dr Jiang said.

The researchers' findings included:

- Introducing a MUP of $1.30 per standard drink across Australia (equal to the current floor price in the Northern Territory) could see alcohol consumption fall by 10.7 per cent (1.5 standard drinks per week) on average; 14.2 per cent (12 standard drinks per week) among harmful drinkers; and 3 per cent (0.2 standard drinks per week) among moderate drinkers

- Applying a uniform excise tax rate of $0.97 per standard drink (equal to the 2013 spirits tax rate) across all beverages could generate a similar impact to the $1.30 MUP policy, but with greater impact on moderate drinkers, with an 8.8 per cent fall in consumption (0.4 standard drinks per week)

- Introducing a MUP at $1.30 or $1.50 has the potential to improve health inequalities in Australia, as it could reduce consumption particularly among harmful drinkers and lower income drinkers, with comparatively smaller impacts on moderate drinkers and higher income drinkers

"Although applying a uniform tax rate across all beverages or introducing a $1.30 minimum unit price across all states and territories could have a similar impact on overall alcohol consumption, the beneficiaries are quite different," Dr Jiang said.

"The former will increase tax revenue for the federal government while the latter will only increase sales revenue, benefitting alcohol retailers, wholesalers and/or producers.
"Our findings show it's time we had a discussion on alcohol pricing or tax reform in Australia."

At around 1 a.m. local standard time on April 29, 2017, a fireball flew over Kyoto, Japan. Compared to other fireballs spotted from Earth, it was relatively bright and slow. Now, scientists have determined not only what the fireball was, but also where it came from.

"We uncovered the fireball's true identity," says Toshihiro Kasuga, paper author and visiting scientist at the National Astronomical Observatory of Japan and Kyoto Sangyo University. "It has a similar orbit to that of the near-Earth asteroid 2003 YT1, which is likely its parent body."

2003 YT1, a binary asteroid first detected in 2003, appears to have been active in the past, meaning it fissured and released dust particles, such as the one responsible for the 2017 fireball. It does not currently show any activity, though, according to Kasuga. However, the researchers found that the orbit, estimated radiant point, velocity and appearance date of the 2017 fireball are all consistent with dust particles that originated from 2003 YT1.

"The potential break-up of the rock could be dangerous to life on Earth," Kasuga says. "The parent body 2003 YT1 could break up, and those resulting asteroids could hit the Earth in the next 10 million years or so, especially because 2003 YT1 has a dust production mechanism."

The researchers found that this dust production mechanism, or the asteroid's likelihood of releasing dust and rock particles, stems from its rotational instability in a process called the YORP effect. When the asteroid is warmed by the Sun, the energy results in a small thrust, which can produce a corresponding recoil, depending on the gravitational pull and other physical variables. The recoil can twist the asteroid, introducing a rotational change. The change can be at physical odds with the gravity and/or other forces, and force the asteroid to physically break -- even just a little, a process which produces dust.

"The released particles can enter Earth's atmosphere and appear as fireballs, which is exactly what happened in 2017," says Kasuga.

According to Kasuga, that particular fireball was not a threat to Earth, as it was estimated to only be a few centimeters in size. Something so small would burn up before it reached the surface.

"The 2017 fireball and its parent asteroid gave us a behind-the-scenes look at meteors," says Kasuga. "Next, we plan to further research predictions for potentially hazardous objects approaching the Earth. Meteor science can be a powerful asset for taking advanced steps towards planetary defense."

One in six women experience long-term post-traumatic stress following miscarriage or ectopic pregnancy.

This is the finding of the largest ever study into the psychological impact of early-stage pregnancy loss, from scientists at Imperial College London and KU Leuven in Belgium.

The research, published in the journal American Journal of Obstetrics and Gynaecology, studied over 650 women who had experienced an early pregnancy loss, of whom the majority had suffered an early miscarriage (defined as pregnancy loss before 12 weeks), or an ectopic pregnancy (where an embryo starts to grow outside the womb and is not viable).

The study revealed that one month following pregnancy loss, nearly a third of women (29 per cent) suffered post-traumatic stress while one in four (24 per cent) experienced moderate to severe anxiety, and one in ten (11 per cent) had moderate to severe depression.

Nine months later, 18 per cent of women had post-traumatic stress, 17 per cent moderate to severe anxiety, and 6 per cent had moderate to severe depression.

The team behind the research, funded by the Imperial Health Charity and the Imperial NIHR Biomedical Research Centre, call for immediate improvements in the care women receive following an early-stage pregnancy loss.

Professor Tom Bourne, lead author of the research from Tommy's National Centre for Miscarriage Research at Imperial College London said: "Pregnancy loss affects up to one in two women, and for many women it will be the most traumatic event in their life. This research suggests the loss of a longed-for child can leave a lasting legacy, and result in a woman still suffering post-traumatic stress nearly a year after her pregnancy loss."

Professor Bourne, who is also a Consultant Gynaecologist, added: "The treatment women receive following early pregnancy loss must change to reflect its psychological impact, and recent efforts to encourage people to talk more openly about this very common issue are a step in the right direction. Whilst general support and counselling will help many women, those with significant post-traumatic stress symptoms require specific treatment if they are going to recover fully. This is not widely available, and we need to consider screening women following an early pregnancy loss so we can identify those who most need help."

The research follows an earlier pilot study in 2016, which investigated the psychological impact of early-stage pregnancy loss in 128 women one and three months after miscarriage or ectopic pregnancy.

One in four pregnancies ends in miscarriage - most often before or around 12 weeks. Estimates suggest there are 250,000 miscarriages every year in the UK, and around 11,000 emergency admissions for ectopic pregnancies. The latter always result in pregnancy loss, as an embryo grows in an area outside of the womb and is unable to develop.

In the study 537 women had suffered a miscarriage before 12 weeks of pregnancy, while 116 had suffered an ectopic pregnancy.

The women in the study attended the Early Pregnancy Assessment Units at three London hospitals - Queen Charlottes and Chelsea, St Mary's, and Chelsea and Westminster.

All were asked to complete questionnaires about their emotions and behaviour one month after pregnancy loss, then again three and nine months later.

Their responses were compared to 171 women who had healthy pregnancies. The results revealed the latter women's levels of psychological symptoms were significantly lower than those found in women who had suffered early pregnancy loss.

The women in the study who met the criteria for post-traumatic stress reported regularly re-experiencing the feelings associated with the pregnancy loss, and suffering intrusive or unwanted thoughts about their miscarriage. Some women also reported having nightmares or flashbacks, while others avoided anything that might remind them of their loss.

The authors caution the study used a questionnaire for screening for post-traumatic stress, but formal diagnosis of post-traumatic stress disorder would require a clinical interview.

The team also explain that women who were already experiencing symptoms of post-traumatic stress and depression may have been more likely to respond to the questionnaire, which could mean the number of women suffering psychological symptoms may appear higher.

However, they add that the fact that such a large proportion were experiencing symptoms suggests many women could be suffering in silence. Dr Jessica Farren, first author of the research from Imperial College, and Obstetrician and Gynaecologist, said: "Post-traumatic stress can have a toxic effect on all elements of a person's life - affecting work, home and relationships."

"We have made significant progress in recent years in breaking the silence around mental health issues in pregnancy and postnatally, but early pregnancy losses are still shrouded in secrecy, with very little acknowledgement of how distressing and profound an event they are. Many women don't tell colleagues, friends or family they are pregnant before the 12-week scan, leaving them feeling unable to discuss their emotions if they suffer a pregnancy loss. We also know partners can suffer psychological distress following miscarriage or ectopic pregnancy, and are investigating this in ongoing research."

The team's research will also now focus on identifying which women are at risk of developing psychological symptoms after pregnancy loss, the impact of early pregnancy loss on partners and also the best type of treatments and how to deliver these.

Ian Lush, Chief Executive of Imperial Health Charity, said: "As the dedicated charity for the Imperial College Healthcare NHS Trust hospitals, we are committed to supporting pioneering research that leads to real improvements in patient care through our annual research fellowships programme. "Dr Farren's study clearly shows that a miscarriage or ectopic pregnancy can have profound and long-lasting impacts on women's mental health and we look forward to seeing how this important research can be translated into better care for patients and their families in the future."

Jane Brewin, Chief Executive of Tommy's comments, said: "For too long women have not received the care they need following a miscarriage and this research shows the scale of the problem. Miscarriage services need to be changed to ensure they are available to everyone, and women are followed up to assess their mental wellbeing with support being offered to those who need it, and advice is routinely given to prepare for a subsequent pregnancy."

Kate Rawson, an actor and playwright, experienced two miscarriages in 2014 and 2015, one at 8 weeks and one at 11 weeks. She has written a radio play about recurrent miscarriage called Little Blue Lines. Here she discusses her experience:

"After my first miscarriage I was numb. I did not know how to react or who to approach. I did not know if it was grief that I was feeling, or if that was even a valid response to have about losing something so 'small'. So I tried to believe reassuring words ('it's not your fault; you can try again; you've got time; it's just one of those things.')

The second time it happened I knew something was wrong immediately, just a faint pink patch in my pants, a slight cramping feeling. Then dread and anxiety at what was to come, and guilt at what I could have done to cause it; sadness for myself, but also my husband, my family, my friends who would have to do all those sad faces and texts and calls again. The physical miscarriage was a huge shock, one I was absolutely not prepared for and I will never forget it.

I tried to 'move on' as advised. 'Trying again' was full of anxiety that got worse when I fell pregnant for the third time. Happily that resulted in a healthy full term birth, but the first trimester was extremely stressful, for both myself and my husband. I struggled to keep perspective and flitted between wanting this baby more than anything else to wishing I would just bleed and get the awful thing over with and my life back.

It was only after my son was born I realized the enormity of what I had been through, and the need to process it - there are support groups at my hospital now but there was nothing available to me at the time - so I wrote about it."