Culture

WASHINGTON, November 3, 2020 -- Certain molecules bind tightly to the surface of ice, creating a curved interface that can halt further ice growth. Some insects, plants, and sea-dwelling creatures contain protein molecules of this type that act as natural antifreeze agents, allowing the organisms to withstand freezing temperatures.

In The Journal of Chemical Physics, by AIP Publishing, scientists report a computational method to model ice binding using a biasing technique to drive the formation of ice in the simulation.

Antifreeze proteins act by binding to an existing interface between ice and liquid water. The resulting curved surface stops the growth of ice. There are also ice-nucleating molecules that catalyze the formation of ice from supercooled liquid water.

Both phenomena require an understanding of the way that molecules bind to ice. Understanding ice binding is important for applications as diverse as cryopreservation of organs and climate modeling, but no computational methods to efficiently model this phenomenon have existed to date.

"The central advantage of the ice-biasing simulation approach is that it simultaneously identifies the ice-binding surface, the face of ice it binds to, and the mode of binding," said author Valeria Molinero.

The investigators created two types of models. One type is an all-atom model that contains all the atoms in the liquid and ice phases of water as well as in the antifreeze-type molecule. The other type of model studied is called a coarse-grained model, which saves computational resources by blending atoms together into simpler structures.

The study looked at a number of molecules that bind ice, including polyvinyl alcohol, a synthetic ice-recrystallization inhibitor, as well as natural antifreeze proteins, such as one from the beetle Tenebrio molitor. Proteins present a simulation challenge, since they have very small surfaces that bind ice. This limits the size of the ice crystal they can bind.

Some systems possess more than one location where ice can bind. This is the case for the natural antifreeze protein in the sea-ice diatom Frailariopsis cylindrus. To determine whether a protein like this has more than one ice-binding surface, IBS, the investigators developed a method they dubbed "cap and repeat."

"In this strategy, we first performed a biased simulation to detect an IBS. Then, we cap that IBS to prevent ice formation on it and perform a second biasing simulation to find out whether ice forms in other sites," said Molinero.

The methods developed in this study show great promise for a number of applications, including finding molecules to protect frozen tissues during storage, furthering the understanding of natural antifreeze proteins, and in climate models, where ice nucleation in the atmosphere plays a key role.

Over 70 percent of U.S. adults have overweight or obesity. While primary care physicians (PCPs) are often the most immediate source of counseling for those trying to lose weight, most PCPs do not have the time, training, or support to guide their patients through a comprehensive weight loss program. Additionally, studies of online weight loss programs have found mixed levels of success. Population health management programs, which are delivered by non-clinical staff members, have emerged as supplemental support systems that offer outreach for preventive and chronic condition care needs, outside of primary care visits. Researchers from Brigham and Women's Hospital paired an online weight loss program with a phone- and email-based population health management program, a two-pronged strategy previously unexplored, and determined that patients in the combined program had greater weight loss over 12 months than patients in the other two groups. Findings are published in the JAMA.

"Population health managers are already doing outreach to people who would benefit from weight loss, such as patients with hypertension or type 2 diabetes," said corresponding author Heather Baer, ScD, an associate epidemiologist in the Division of General Internal Medicine and Primary Care at the Brigham. "The idea was to leverage population health management, which is a strategy that's been implemented at the Brigham and in other institutions, to see if it could be integrated with an online weight loss program and be sustainable over time."

The study followed 840 patients in the Brigham's Primary Care Center of Excellence, a network of 15 practices, between 2016 and 2019. Participants, all of whom either had overweight or obesity and hypertension or type 2 diabetes, were divided into three study groups. The "usual care" group received general information about weight management in the mail; the "online only" group participated in an online weight-loss program, which included meal plans, activity trackers, and progress reporting features; and the "combined intervention" group participated in the online program while receiving additional outreach and support from non-clinical staff members monitoring their progress.

Over the course of 12 months, the usual care, online only, and combined intervention groups lost an average of 2.7 pounds, 4.1 pounds, and 6.9 pounds, respectively. The researchers found that the combined intervention produced a small but statistically significant increase in weight loss compared to the other two methods. Moreover, participants in the combined intervention group decreased their body weight by an average of 3 percent, a statistically significant difference from the 1.4 and 1.9 percent decreases found in the usual care and online only groups.

The researchers acknowledge that while the amount of weight loss is fairly low, clinically significant health benefits are associated with a 3-5 percent decrease in weight among individuals with overweight or obesity. Approximately one third of participants in the combined intervention group lost 5 percent or more of their weight, compared to only 14.9 and 20.8 percent of participants in the usual care and online only groups, respectively. Moreover, the weight loss in the combined intervention group was also found to be maintained at 18 months, in spite of the fact that active interventions ceased after 12 months.

"Our findings suggest that the combined intervention facilitates potentially sustainable weight loss in the long term," Baer said. She notes that the generalizability of the team's findings is limited, given that the the majority of participants were white, well-educated, and English-speaking. Nevertheless, the combined intervention approach may offer an effective form of weight management that is more easily available to some patients who may face barriers in accessing traditional in-person care.

The results are especially notable as health care increasingly shifts to virtual forms amidst the COVID-19 pandemic. "We knew that online weight loss programs can be more convenient, accessible, and cheaper for patients, but now both physicians and patients have become more comfortable with the idea of care being delivered virtually," Baer said. "Virtual care is going to stay with us post-pandemic, and this study provides more evidence that even pre-pandemic, virtual care for some conditions is working."

What The Study Did: This observational study estimates the 10-year risk for disease progression, surgery, metastasis, and cause-specific and all-cause mortality among African American men with low-risk prostate cancer managed with active surveillance.

A novel method to sample earwax could be a cheap and effective way to measure the hormone cortisol, according to a study led by researchers at UCL and King's College London.

The findings, published in the academic journal Heliyon, could point to new ways of monitoring depression and stress-linked conditions.

The new device can be used at home without clinical supervision, facilitating medical check-ups while maintaining social distancing due to COVID-19, and may also have the potential to measure glucose or COVID-19 antibodies that accumulate in earwax.

Lead researcher Dr Andres Herane-Vives (UCL Institute of Cognitive Neuroscience and Institute of Psychiatry, Psychology & Neuroscience, King's College London) said: "Cortisol sampling is notoriously difficult, as levels of the hormone can fluctuate, so a sample might not be an accurate reflection of a person's chronic cortisol levels. Moreover, sampling methods themselves can induce stress and influence the results.

"But cortisol levels in earwax appear to be more stable, and with our new device, it's easy to take a sample and get it tested quickly, cheaply and effectively."

Cortisol has been considered as a possible biomarker, or objective biological measure, for depression, but researchers have been stymied by challenges in accurately measuring cortisol levels. The most common technique is with hair samples, but they are more subject to short-term fluctuations in cortisol, and not everyone has enough hair for a reliable sample.

It is also more time-consuming and expensive to analyse hair samples, compared to earwax, but until now there has not been a reliable and non-stressful method to sample earwax.

To develop the new device, Dr Herane-Vives was inspired by another natural wax, honeycomb from bees, as it is known to be well-preserved and resistant to bacterial contamination. Earwax has similar properties, making it well suited for home sampling, as samples can be sent to a lab by post without much risk of contamination.

The novel earwax self-sampling device is similar to a cotton swab, but with a brake that stops the swab from going too far into the ear and causing damage. The tip is covered with a sponge of organic material, with a solution that has been tested to be the most effective and reliable at taking samples.

In their pilot study, Dr Herane-Vives and a team of researchers from the UK, Chile and Germany brought in 37 study participants to test different cortisol sampling techniques. The research team sampled participants' earwax using a standard syringe procedure, known to be somewhat painful, and then followed up a month later by using the same sampling in one ear, and the novel sampling technique in the other ear, which the participants could administer themselves. The researchers also analysed hair and blood samples from the same participants.

The researchers found that earwax samples yielded more cortisol than hair samples, and the new technique was the fastest and potentially cheapest method. The novel technique was the least influenced by confounding factors such as stressful events or alcohol consumption contributing to cortisol fluctuations over the previous month. In another recent study, participants rated the new self-sampling device as more comfortable than traditional methods.

Dr Herane-Vives is now setting up a company, Trears, to bring his earwax sampling device to market, with support from the UCL Hatchery startup incubator.

He and his team are also investigating whether the device could be useful to measure glucose levels from earwax samples, for monitoring of diabetes, and potentially even COVID-19 antibodies.

Dr Herane-Vives said: "After this successful pilot study, if our device holds up to further scrutiny in larger trials, we hope to transform diagnostics and care for millions of people with depression or cortisol-related conditions such as Addison's disease and Cushing syndrome, and potentially numerous other conditions."

New findings from researchers at Washington University School of Medicine in St. Louis suggest the eye's cornea can resist infection from the novel coronavirus. Although the herpes simplex virus can infect the cornea and spread to other parts of the body in patients with compromised immune systems, and Zika virus has been found in tears and corneal tissue, SARS-CoV-2, the virus that causes COVID-19, does not appear to replicate in the human cornea.

The researchers have yet to determine, however, whether other tissue in and around the cornea, such as the tear ducts and the conjunctiva, are vulnerable to the virus.

The new findings are published Nov. 3 in the journal Cell Reports.

"Our findings do not prove that all corneas are resistant," said first author Jonathan J. Miner, MD, PhD. "But every donor cornea we tested was resistant to the novel coronavirus. It's still possible a subset of people may have corneas that support growth of the virus, but none of the corneas we studied supported growth of SARS-CoV-2."

Miner, an assistant professor of medicine, of molecular microbiology and of pathology and immunology, teamed up with ophthalmologist Rajendra S. Apte, MD, PhD, to study mouse and human corneas exposed to the herpes simplex, Zika and SARS-CoV-2 viruses.

"Some COVID-19 patients get eye symptoms, such as conjunctivitis (pinkeye), but it's not clear that the viral infection itself causes that; it could be related to secondary inflammation," said Apte, the Paul A. Cibis Distinguished Professor in the John F. Hardesty Department of Ophthalmology & Visual Sciences. "The cornea and conjunctiva are known to have receptors for the novel coronavirus, but in our studies, we found that the virus did not replicate in the cornea."

Prior research in human and mouse corneal tissue had demonstrated that Zika virus could be shed in tears, and the researchers wanted to learn whether the cornea might serve as an entry point for SARS-CoV-2. Apte, Miner and their colleagues tested that by exposing the eye tissue to the different viruses and observing whether they could grow in and replicate. They also identified key substances in corneal tissue that can promote or inhibit viral growth.

One inhibitor they identified is called interferon lambda. They found that interferon lambda prevented efficient growth of Zika virus and herpes simplex virus in the cornea. But with SARS-CoV-2, levels of the substance had not effect on whether the virus could replicate. It simply could not gain a foothold whether interferon lambda was present or not.

That's reassuring to Apte, also a professor of developmental biology and of medicine, who said it suggests COVID-19 probably cannot be transmitted through a cornea transplant or similar procedures in the eye.

"Our data suggest that the novel coronavirus does not seem to be able to penetrate the cornea," Apte said.

Miner added, however, that because of unknowns involving the tear ducts and the conjunctiva, it's too soon to dismiss the importance of eye protection.

"It's important to respect what this virus is capable of and take appropriate precautions," he said. "We may learn that eye coverings are not necessary to protect against infection in the general community, but our studies really are just the beginning. We need larger clinical studies to help us better understand all the potential routes of SARS-CoV-2 transmission, including the eye."

Professor Xie Guangming's group in the College of Engineering at Peking University has found a simple yet previous unknown rule, explaining how do schooling fish save energy in collective motion. The related work has been published in Nature Communications.

Collective behaviour has drawn a great interest to biologists. A well-known example is that geese fly in "V"-shape or "-"-shape formations in long-distance migrations to reduce drag and thus to save energy. Similarly, as it is a common phenomenon that fish swim in schools, can fish also save energy by swimming in groups? Since Daniel Weihs (1973) proposed a possible energy-saving mechanism for schooling fish, the investigation of energy-saving mechanisms in collective underwater swimming has attracted a long and widespread interest among biologists and roboticists. The former want to reveal the essential mechanisms behind natural phenomena, while the latter want to learn from nature and apply them in the field of engineering. However, it is still not known whether, and if so, how, schooling fish can save energy by interacting with the vortices shed by neighbours.

Professor Xie's group used the high fidelity bio-inspired robotic fish developed by themselves as a physical experimental model to explore the mechanism. They conducted over 10,000 trials on collective swimming robotic fish in the low-turbulence flow tank platform at the State Key Laboratory of Turbulence and Complex Systems, Peking University. A simple rule was found to explain how the follower can save energy by adjusting its body undulation relative to the leader. In order to verify whether this rule is also adopted by real fish, Professor Xie's group, together with Professor Iain D. Couzin's group at the Max-Planck-Institute of Animal Behaviour, Germany, analysed the relationship between the formation and relative undulations of fish bodies at different swim speeds, and verified that this simple rule is also used by real fish for saving energy. In particular, after impairing the vision and lateral line perception in real fish, they found that real fish do not require complex perception and brain processing to adopt this rule, indicating this rule might be universal in biological systems.

These results not only suggest a potential energy-saving mechanism for fish school, but also can inspire roboticists to design control algorithms for underwater robot swarm.

Few beef producers in the temperate climate of southern Australia will have encountered the parasitic buffalo fly (Haematobia irritans exigua), a scourge of the cattle industry in the country's tropical and subtropical north - but maintaining this state of affairs, and also lifting a burden off the northern industry, has become a race against time, and climate.

Buffalo fly is a serious animal health and production challenge, costing the northern Australian cattle industry almost $100 million a year in treatments and lost production. But control of the pest with insecticides is running into increasing resistance, plus there is a need to protect Australian beef's 'clean green' reputation and so minimise the need for pesticides.

Over the past century the buffalo fly has been creeping southwards through Queensland to northern New South Wales and modelling shows that, aided by climate change, it could reach as far south as South Australia and south-west Western Australia by 2030. The blood-sucking fly causes large, painful sores and distressed animals can be distracted from feeding enough to seriously affect growth.

The only obstacle in its path is a joint university, industry and Queensland Government biological control project using the insect-infecting bacterium, Wolbachia - the same agent that has been used so successfully to suppress mosquito-transmitted dengue fever in humans.

The project is led by Dr Peter James from the Queensland Alliance for Agriculture and Food Innovation (QAAFI) at The University of Queensland, who explains the key is using the Wolbachia bacterium to break the fly's breeding cycle. If this can be sustained it presents an opportunity to both suppress the buffalo fly population in the north and stop its spread southwards.

The buffalo fly is a formidable foe, having been introduced from Asia into the Northern Territory in the late 1830s, but the chink in its armour is it weakens in cold weather. Its populations tend to shrink into localised pockets. Dr James says if Wolbachia can be used to further stress the buffalo fly in winter, then a local eradication strategy starts to become a real possibility.

But there are some considerable technical challenges still to overcome. Because the bacterium is spread vertically from mother to offspring, not transferred sideways amongst flies, buffalo flies have to be artificially infected by microinjection. With mosquitoes, this is usually done by microinjection into the eggs. That approach hasn't been able to be used for buffalo fly because the eggs are extremely hard: "When we started micro-injecting eggs, as is done with mosquitoes, we were blunting needles and damaging the eggs like you wouldn't believe. Needles were even breaking," says Dr James.

"So from there we looked at micro-injecting adult flies or pupae, the idea being the bacterium would still spread through the insect and get into the germinal tissue of the females."

He says the main thing is to establish the bacterium in the population because once flies are infected, three control scenarios open up. While Wolbachia is a maternally transmitted bacterium, through eggs, male flies can still be used to manipulate this.

If a Wolbachia infected male mates with a healthy female the eggs will be infertile and so no offspring. Conversely, if a healthy male mates with an infected female the mating will be successful with eggs and offspring produced, but they will be carrying Wolbachia and help to spread it through the buffalo fly population. Dr James says the advantage of this is that it saves researchers having to otherwise breed and release millions of infected or sterile flies.

"But Wolbachia also has a whole lot of other impacts on fly population fitness. We have shown that just the presence of the bacterium can shorten the buffalo flies' lifespan, reduce the number of eggs laid, and the number of pupae that hatch. There are probably also other fitness penalties that we haven't yet identified. If you start to add up all these impacts, that can be a heavy load on survivability.

"And this is where the winter factor comes. In many areas the buffalo fly only just hangs on in low numbers through winter so even Wolbachia's effect on population fitness could be enough to wipe out these populations if the bacterium is deployed strategically."

A second approach is to use Wolbachia to block transmission of the Stephanofilaria nematode transmitted by buffalo flies and associated with the development of buffalo fly lesions on the cattle. Similar to the way that Wolbachia blocks transmission of dengue virus, zika virus and a number of other viruses transmitted by mosquitoes, it has also been shown to block transmission of some nematodes closely related to Stephanofilaria. Spread of Wolbachia through the buffalo fly population could block the nematode and alleviate lesion development

A third option being explored is to breed and release sterile males.

"Again, the idea is to use the sterile males strategically by releasing them into those overwintering areas that are already in a weakened state. This could stop or slow the build-up of buffalo fly in the next season or stop the southerly spread or even provide the basis of local eradication strategies."

Dr James says the challenge now is to improve the consistency and persistence of Wolbachia infection. Since the Wolbachia project started in 2017 researchers have achieved the first big challenge of taking different Wolbachia strains from mosquitoes and also fruit fly and introducing them into a whole new species, the buffalo fly: "Wolbachia has been carried across generations in a number of instances, but we have yet to produce a stably infected strain," he explains.

"But we have reached the stage where we can start finessing the approach. For example we have a project looking at ways to immunosuppress the fly to favour Wolbachia infection.

"We've built up a reasonable toolbox so I am confident we are close to providing sustainable biological control that will deliver economic animal welfare relief to the northern cattle industry, and save the southern industry from ever having to endure the same burden."

Ants use their own acid to disinfect themselves and their stomachs. A team from Martin Luther University Halle-Wittenberg (MLU) and the University of Bayreuth has found that formic acid kills harmful bacteria in the animal's food, thereby reducing the risk of disease. At the same time, the acid significantly influences the ant's intestinal flora. The new study was published in the journal eLife.

Formic acid is one of the simplest organic acids. It is produced in a special gland in the abdomen of numerous species of ant. "There was a long-standing assumption that the acid only served to ward off predators, for example insects and birds," says Dr Simon Tragust from the Institute of Biology at MLU, who co-led the new study alongside Professor Heike Feldhaar from Bayreuth. A couple of years ago he was able to show that ants also use the acid in brood care, for example, to disinfect their brood and prevent the spread of harmful fungi.

The new study was based on an observation of the animals' behaviour. "Whenever ants swallow food or water, they start cleaning their hindquarters afterwards," says Tragust. The researcher wanted to figure out why they do that. "For one thing, the behaviour didn't seem to be linked to digestion, because ants do this even after they have only ingested water," he adds.

Through several experiments the team was able to show that ants disinfect themselves on the inside. "When the ants were able to access the acid, their chances of survival increased significantly after eating food enriched with pathogenic bacteria," explains Tragust. What's more, the beneficial effect was not limited to an individual animal. Ants pass food from their mouth to the mouths to their nest mates. "This is a major potential source of infection," says Tragust. If the ant passing on the food has previously ingested the acid, the receiving ant had a lower risk of falling ill. According to Tragust, this behaviour might reduce the spread of infection within the ant colony.

The results of the new study also explain why some ants have very few bacteria in their digestive tracts; those that are present are primarily acid-resistant microbes. "Acid swallowing acts as a filter mechanism, structuring the ant's microbiome," explains Tragust. Ants are one of just a handful of animals with extremely acidic stomachs. "Otherwise this is only known to occur in humans and a few other vertebrates," says Tragust. Unlike ants, stomach acid in humans is produced directly in the stomach, but the effects are the same: The acid kills germs in the food and influences the microbiome of the gut.

Incidentally, how formic acid precisely works is still a mystery, but it and other organic acids have long been used as additives in animal feed to kill harmful germs.

Almost one in five patients with COVID-19 may only show gastrointestinal symptoms, according to a review of academic studies published in the journal Abdominal Radiology. The findings of the review suggest abdominal radiologists need to remain vigilant during the pandemic while imaging patients.

Gastrointestinal symptoms associated with COVID-19 vary widely but can include loss of appetite, nausea, vomiting, diarrhea and generalized abdominal pain. The researchers who conducted the review report that 18 per cent of patients presented with such symptoms, while 16 per cent of COVID-19 cases may only present with gastrointestinal symptoms.

"There's a growing amount of literature showing that abdominal symptomatology is a common presentation for COVID-19," said Mitch Wilson, a radiologist and clinical lecturer in the University of Alberta's Faculty of Medicine & Dentistry.

The researchers, who also included Gavin Low, associate professor of radiology and diagnostic imaging, and medical student Kevin Lui, examined findings from 36 studies published through July 15 to reach their conclusions.

In addition to gastrointestinal symptoms, they also determined potential signs radiologists should look for while conducting abdominal imaging that could be evidence of COVID-19 infection. Those signs include inflammation of the small and large bowel, air within the bowel wall (pneumatosis) and bowel perforation (pneumoperitoneum). The signs are quite rare, said the researchers, and could indicate patients with advanced disease.

"Seeing these things is not necessarily telling us a patient has COVID-19," said Wilson. "It could be from a variety of potential causes. But one of those potential causes is infection from the virus, and in an environment where COVID-19 is very prevalent, it's something to consider and potentially raise as a possibility to the referring physician."

Since the latter half of the 20th century, vacationing has grown increasingly synonymous with tourism. This has been attributed to disposable incomes rising for many people, budget commercial airlines taking to the sky, and multitudes of tour facilitators entering the market, among other things. Now, economies of entire countries depend on tourism. To quote the United Nations World Tourism Organization (UNWTO): "Today, the business volume of tourism equals or even surpasses that of oil exports, food products, or automobiles."

Yet, there have been entire communities of people who do not have the luxury to partake in tourism--for monetary, psychological, cultural, or bureaucratic constraints. Social tourism provides these communities the opportunity to fulfill their vacation desires. But according to Professor Jin Young Chung from Incheon National University, Korea, not all such disadvantaged communities are able to make the most of social tourism. Talking about his paper recently published in the Annals of Tourism Research (made available online on 31 October 2019 and offline in the September 2020 issue), he says: "There exists a hidden population who could benefit from social tourism but tend not to participate at all."

Prof Chung is referring to families in which a parent is battling cancer and is terminally ill. Often buried under brutal treatment regimens, the burden of bills, and low morale, these families cannot see vacation as a priority. However, Prof Chung's research tells us that they need a vacation.

Prof Chung and his colleague Prof Steven Simpson of the University of Wisconsin analyzed notes written by approximately 400 such families after they had benefitted from a social tourism program run by a non-profit charitable organization in the US.

"I don't think any of us knew how much we needed a break from all the doctor's appointments..." one family said. "...one of the first thoughts I got was how do I spend as much time as I can with my kids making good memories to last them a lifetime?" a mother had written. Because of this social tourism program, the families had recognized their latent tourism need.

"The most important memory was seeing my daughter's eyes light up and the sound of her laughter," wrote another parent. The trip had gotten families to realize that there were precious benefits to this vacation. Not only did it take them away from the worries of daily life and treatment, it brought them closer and left positive mental impressions on the children.

Several notes also made it clear that these realizations would not have come to fruition if their medical or social points of contact, such as nurses and social workers, had not nudged them to consider the social tourism program. "Public health professionals and health clinics should consider educating oncologists and social workers on the importance of travel and leisure programs for families with a terminally ill cancer parent, where the parent is preparing to leave their children behind and whose families are preparing to live life without them," Prof Chung reiterates.

Researchers of tourism mobility and organizations such as the UNWTO care about making tourism sustainable and accessible for all. But this analysis by Profs Chung and Simpson brings to the fore the fact that hidden communities exist who remain excluded from such focus. It is time research is done to unearth them and understand their needs, so tourism can one day truly become accessible for all.

Prof. Dr. Thomas Kenkmann, geologist from the University of Freiburg's Institute of Earth and Environmental Sciences, together with mineralogist Prof. Dr. Wolf Uwe Reimold from the University of Brasilia, Brazil, and Dr. Manfred Gottwald from the German Aerospace Center (DLR) published an atlas providing a comprehensive overview of all known impact craters on every continent. The authors present the more than 200 terrestrial impact sites in high-resolution topographic maps and satellite images, complete with detailed geological descriptions and photographs of the crater structures and their rocks. They also explain the essential details of each impact event.

The formation of craters by asteroid and comet impact has always been a fundamental process in the solar system, explains Kenkmann. As the planets developed along with their moons, these impacts played an important part in accreting planetary mass, shaping the surfaces of planetary bodies, and later also influencing their development. And larger meteorite impacts eventually affected the development of life on Earth.

Today, mapping of what can still be seen of the impact structures on the Earth's surface can be done by satellites in low Earth orbit. From 2010 to 2016, the DLR successfully measured the Earth's surface with the radar satellites of the TanDEM-X mission. The acquired data allowed, for the first time, to derive a worldwide terrain model with a height accuracy of up to one meter. From this global digital elevation model the authors have been able to produce this complete topographic atlas of 600 pages with information about all terrestrial impact craters known to date.

On a daily basis, and perhaps without realizing it, most of us are in close contact with advanced AI methods known as deep learning. Deep learning algorithms churn whenever we use Siri or Alexa, when Netflix suggests movies and tv shows based upon our viewing histories, or when we communicate with a website's customer service chatbot.

However, the rapidly evolving technology, one that has otherwise been expected to serve as an effective weapon against climate change, has a downside that many people are unaware of -- sky high energy consumption. Artificial intelligence, and particularly the subfield of deep learning, appears likely to become a significant climate culprit should industry trends continue. In only six years -- from 2012 to 2018 -- the compute needed for deep learning has grown 300,000%. However, the energy consumption and carbon footprint associated with developing algorithms is rarely measured, despite numerous studies that clearly demonstrate the growing problem.

In response to the problem, two students at the University of Copenhagen's Department of Computer Science, Lasse F. Wolff Anthony and Benjamin Kanding, together with Assistant Professor Raghavendra Selvan, have developed a software programme they call Carbontracker. The programme can calculate and predict the energy consumption and CO2 emissions of training deep learning models.

"Developments in this field are going insanely fast and deep learning models are constantly becoming larger in scale and more advanced. Right now, there is exponential growth. And that means an increasing energy consumption that most people seem not to think about," according to Lasse F. Wolff Anthony.

One training session = the annual energy consumption of 126 Danish homes

Deep learning training is the process during which the mathematical model learns to recognize patterns in large datasets. It's an energy-intensive process that takes place on specialized, power-intensive hardware running 24 hours a day.

"As datasets grow larger by the day, the problems that algorithms need to solve become more and more complex," states Benjamin Kanding.

One of the biggest deep learning models developed thus far is the advanced language model known as GPT-3. In a single training session, it is estimated to use the equivalent of a year's energy consumption of 126 Danish homes, and emit the same amount of CO2 as 700,000 kilometres of driving.

"Within a few years, there will probably be several models that are many times larger," says Lasse F. Wolff Anthony.

Room for improvement

"Should the trend continue, artificial intelligence could end up being a significant contributor to climate change. Jamming the brakes on technological development is not the point. These developments offer fantastic opportunities for helping our climate. Instead, it is about becoming aware of the problem and thinking: How might we improve?" explains Benjamin Kanding.

The idea of Carbontracker, which is a free programme, is to provide the field with a foundation for reducing the climate impact of models. Among other things, the programme gathers information on how much CO2 is used to produce energy in whichever region the deep learning training is taking place. Doing so makes it possible to convert energy consumption into CO2 emission predictions.

Among their recommendations, the two computer science students suggest that deep learning practitioners look at when their model trainings take place, as power is not equally green over a 24-hour period, as well as what type of hardware and algorithms they deploy.

"It is possible to reduce the climate impact significantly. For example, it is relevant if one opts to train their model in Estonia or Sweden, where the carbon footprint of a model training can be reduced by more than 60 times thanks to greener energy supplies. Algorithms also vary greatly in their energy efficiency. Some require less compute, and thereby less energy, to achieve similar results. If one can tune these types of parameters, things can change considerably," concludes Lasse F. Wolff Anthony.

The proportion of those, who say that they meet less frequently with family or friends, rose from 65 to 76 percent. Furthermore, 69 percent say, they leave their home less - an increase by 10 percentage points. "With the current increase in the number of infections, people in Germany are becoming more cautious again," comments BfR-President Professor Dr. Dr. Andreas Hensel on the latest developments.

https://www.bfr.bund.de/cm/349/201027-bfr-corona-monitor-en.pdf

The majority considered the measures in force until the end of last week to be appropriate. Nevertheless, acceptance particularly for the restrictions in the cultural sector has decreased from 82 percent at the end of September to 71 percent at the end of October. The recently introduced mandated closing time, that is, closing eating and dining venues in the late evening hours, was supported by 59 percent of the respondents. Two thirds considered the associated ban on selling alcohol to be appropriate.

The current survey also shows that some concerns are growing. Now, around a quarter of the respondents are worried about their physical and mental health and a third (35 percent) about their social relationships. About one in five is still concerned about their own economic situation.

For the first time, the BfR-Corona-Monitor also measured how often the respondents use different types of media to inform themselves about the coronavirus. It was found that for this purpose more than half of the respondents watch television (61 percent) and listen to the radio (55 percent) on a daily basis. For the majority, personal contacts are also an important source of information: 89 percent state that they obtain information by talking to others at least once a week. Print media and social media, however, are used less than once a week or never by most people (50 and 66 percent).

The BfR continually adapts its FAQs on the topic of coronavirus to the current state of science:

https://www.bfr.bund.de/en/can_the_new_type_of_coronavirus_be_transmitted_via_food_and_objects_-244090.html

In Alzheimer's disease, a protein (peptide) forms clumps in the brain and causes sufferers to lose their memory. In a recently published article, a research group at Uppsala University described a new treatment method that increases the body's own degradation of the building blocks that lead to these protein clumps.

In Alzheimer's disease, the peptide amyloid-beta begins to form clumps in the brain. This process is called aggregation and the clumps so created are called aggregates. The treatment methods for Alzheimer's disease that are currently in clinical trials are attempts to bind to these disease-causing aggregates. But they are unable to bind to the smallest aggregates, which many now believe are the most toxic to neurons.

The treatment method developed in the new Uppsala research study using mice degrades the building blocks from which these aggregates form before they have a chance to aggregate. This treatment method therefore reduces the formation of all types of aggregates.

It has long been known that the peptide somatostatin, which was used by the researchers in the Uppsala group, can activate the body's own degradation of amyloid-beta, which is the peptide that forms the aggregates. However, it has not been possible to use somatostatin as a drug in the past because it has a very short half-life in the blood of only a few minutes, and does not cross the blood-brain barrier into the brain where the aggregates are formed.

"So to be able to use somatostatin as a treatment, we fused it to a brain transport protein which allows the somatostatin to enter the brain. This has proved very effective. When we used the transport protein, we also saw that the time that the somatostatin remained in the brain increased to several days, which is fantastic," says Fadi Rofo, doctoral student at the Department of Pharmaceutical Biosciences and the study's first author.

In the study, the researchers saw the greatest effect in hippocampus, the part of the brain that forms memories and the first part to be affected by Alzheimer's disease.

"The fact that we have seen that the effect is most evident in the hippocampus in particular is very good. Our hope is that this method will be able to act in a very targeted way and have few side effects, which have been a problem in other studies," says Greta Hultqvist, assistant professor at the Department of Pharmaceutical Biosciences, who led the research study.

The study was conducted in mice, but the researchers believe that somatostatin would have the same effect in humans and that this type of treatment could be more effective than those trialled so far.

In the condition known as cavernoma, lesions arise in a cluster of blood vessels in the brain, spinal cord or retina. Researchers from Uppsala University can now show, at molecular level, that these changes originate in vein cells. This new knowledge of the condition creates potential for developing better therapies for patients. The study has been published in the journal eLife.

The vascular lesions, or blood-vessel malformations, that appear in a cerebral cavernoma - also known as a cerebral cavernous malformation (CCM) or, in the US, cavernous angioma - resemble mulberries. They bleed easily, which may cause epileptic attack, neurological problems and stroke. The condition is due to genetic mutations that may be inherited or occur spontaneously, and is incurable at present. Surgery is an option but, in patients with the hereditary form in whom new CCMs arise constantly, only a temporary solution.

How, and in which kind of blood vessel, the mutations occur has not been entirely clarified to date. In the present study, the researchers at Uppsala University - in collaboration with IFOM, the FIRC Institute of Molecular Oncology, and the Mario Negri Institute of Pharmacological Research in Italy - investigated endothelial cells. The function of these cells, which line the interior of blood vessels, varies according to vessel type, contributing to the differing features of arteries, veins and capillaries. In all, the scientists have analysed more than 30,000 individual endothelial cells in detail to identify how, and in which vessels, CCMs appear.

"One of the genes that may mutate in the inherited form of CCM is called CCM3. We've examined mouse brain endothelial cells, after specific endothelial deletion of CCM3. The cells were clustered in venous and arterial endothelial cells, and we were able to see that venous endothelial cells were particularly sensitive to loss of the CCM3 gene," says Peetra Magnusson of the Department of Immunology, Genetics and Pathology (IGP).

When CCM3 was lacking in mural endothelial cells of the venous type, the researchers observed increased cell division and abnormal growth of the vessels, leading to the characteristic mulberry-like lesions. The study thus confirms, at molecular level, that the vascular malformations of a cavernoma arise in veins. This had been seen previously only when the structure of the blood vessels had been studied in vessel fragments.

"Another interesting result from the study was that arterial endothelial cells were not affected at all in the same way by losing their CCM3. Although the CCM3 gene was also missing in these cells, they don't contribute to development of the malformations," says Elisabetta Dejana, who led the study.

"Summing up, our findings have brought new knowledge about cavernoma, which should improve the chances of developing improved clinical treatments."