Earth

Twice as many eligible patients got screened for hepatitis C when it was already ordered for them compared to those who had to request it, according to a new study by researchers at the Perelman School of Medicine at the University of Pennsylvania. Additionally, the patients in the study - whose average age was 63 - completed their screenings much more often when they were contacted via mail as opposed to electronic messaging. The study was published today in BMJ.

"We think that sending the lab order with outreach was so successful because it framed screening as the default," said the study's lead author, Shivan Mehta, MD, the associate chief innovation officer at Penn Medicine. "However, this strategy was also successful because it reduced effort and the number of steps to screen by both the patient and clinician."

More than 21,000 patients born between 1945 and 1965 - due to the high instances of hepatitis C but low screening rates in this population - were enrolled in the study. In Pennsylvania, where the study took place, state law requires health systems to offer screening to patients in this demographic. So the researchers decided this was a good venue to see if they could improve upon and rigorously evaluate something they were doing anyway.

Patients were chosen from participating primary care practices in the Philadelphia region and randomized into a number of groups to compare which resulted in higher screening rates: one examining whether pre-ordered screening tests were better than traditional outreach, another looking into mailed versus electronic communication, and the last trying out behavioral science-informed messaging. The study's active phase stretched 12 months from April 2019 until May 2020.

Mehta and his colleagues add more evidence to behavioral science's tenet that it's best to make the most beneficial choice the easiest. In the arm of the study where patients received a screening order in addition to the usual reminder letter, 43 percent of the patients completed their hepatitis C screening within four months; just 19 percent got screened if they only received the reminder letter with no lab order. This was what the researchers believed they'd find.

But the study had some unexpected findings. When the researchers compared the group of patients who received a mailed letter notification against a group who were notified via an online patient portal - like those many health systems use - the electronic method underperformed slightly, though not significantly. Roughly 18 percent of the patients mailed letters completed screening versus 14 percent of those who were contacted via a patient portal. There was a specifically pronounced divide when it came to Black patients in this phase of the study, as 11 percent fewer completed screenings if they were reminded via the patient portal.

"This was the biggest surprise for us. Many presume that most people are moving digital towards email, but for some populations, traditional letters might be best," Mehta said. "Additionally, the user experience of the secure messages also may have had to do with the lower response rate. Patients need to click on a link and remember their password, which may pose challenges."

Another slight surprise was the messages with content informed by behavioral science (such as "Join the majority of other patients who have been screened for Hepatitis C" or "Write down a date when you will get your screening done") did not make a difference in screening rates. A single percentage point separated the two groups of patients: roughly 15 percent of patients who were reached with traditional messaging were screened compared to about 14 percent of those from the behavioral science group.

"One of our hypotheses is that the behavioral-informed messages had a longer message, which may have been too much for patients," Mehta explained. "There is some evidence that shorter messages may be more effective. That may be the case in this situation."

Mehta said this study can inform clinical efforts beyond hepatitis C screening, assisting screenings and preventive care for other conditions.

Within hepatitis C, though, the researchers believe that the attachment of the order for screening was the greatest overall driver, so they hope to use that technique digitally, as well, to potentially boost those numbers. And screening recommendations are expanding to include all adults older than 18, which means there is a whole new population to reach.

Ikoma, Japan - In neurons, changes in the size of dendritic spines - small cellular protrusions involved in synaptic transmission - are thought to be a key mechanism underlying learning and memory. However, the specific way in which these structural changes occur remains unknown. In a study published in Cell Reports, researchers from Nara Institute of Science and Technology (NAIST) have revealed that the binding of cell adhesion molecules with actin, via an important linker protein in the structural backbone of synapses, is vital for this process of structural plasticity.

Actin proteins make up an important part of a cell's structure, or cytoskeleton, and allow for dynamic changes in this structure by forming microfilaments when growth or movement is required. It was originally thought that the polymerization of actin was all that was needed for dendritic spines to change size in response to synaptic activation, but researchers at NAIST found that this process alone was not enough to cause structural plasticity, and decided to address this problem.

"Current models of structural plasticity in dendritic spines do not take mechanical force into account," says Naoyuki Inagaki, corresponding author. "We had already identified the role of shootin1a, a protein involved in neuronal development, in axon growth and so we wanted to investigate whether this protein might also have a role in the structural plasticity of dendritic spines."

To explore this question, the researchers used neurons of control and shootin1a knockout rodents to examine whether shootin1a was involved in the formation of dendritic spines. The researchers wanted to determine if mechanical force was generated in dendritic spines by the shootin1a-mediated coupling of actin and cell adhesion molecules - cell-surface proteins that bind cells together at synapses - similar to what they had observed in axons.

"The results were clear," explains Inagaki. "We found that shootin1a mechanically linked polymerizing actin with cell adhesion molecules in dendritic spines, and revealed that synaptic activity enhanced this coupling, thus allowing the actin filaments to push against the membranes and enlarge spines." The results of this study are the first to link mechanical force with synaptic activity-dependent dendritic spine plasticity and provide new insights into the mechanisms of structural plasticity in these spines.

Given that changes in activity-dependent dendritic spine plasticity have been implicated in multiple neuropsychiatric and neurodegenerative disorders, including autism spectrum disorder and Alzheimer's disease, these findings are important because they suggest that shootin1a disruption may lead to the development of neurological disorders. Future studies into this mechanism of structural plasticity in dendritic spines might provide new drug targets for these disorders.

Research to be published tomorrow in the journal Nature Communications is the first study to quantify the costs of storm damage caused by sea level rise driven specifically by human-induced climate change. Researchers from Stevens Institute of Technology, Climate Central, Rutgers University and other institutions found this self-inflicted damage to be $8.1 billion of Hurricane Sandy's damage and an additional 71,000 people and 36,000 homes exposed to Sandy's flooding.

Hurricane Sandy struck the northeast U.S. coast in 2012, causing widespread destruction estimated at $62.7 billion. This new research not only reveals that 13 percent of the total damages resulted from human-caused sea level rise, but also reports novel modeling techniques that can be applied to other coastal storms to determine the cost associated with human-caused warming of the planet.

"This study is the first to isolate the human-contributed sea level rise effects during a coastal storm and put a dollar sign to the additional flooding damage," said Philip Orton, research associate professor at Stevens and a co-author of the study. "With coastal flooding increasingly impacting communities and causing widespread destruction, pinpointing the financial toll and the lives affected by climate change will hopefully add urgency to our efforts to reduce it."

In their work, the team found that human-caused warming had raised New York-area sea levels roughly four inches over the century preceding the storm, or about 55 percent of all sea level rise observed in the area since 1900. The higher sea levels in New York, New Jersey and Connecticut meant that the storm surge could penetrate further inland than it otherwise would have been able to --enough to deepen flood waters everywhere, increasing damage to submerged structures.

Damage estimates of human-caused sea level rise were based on hydrodynamic modeling to simulate the effect of various sea levels on the impacts of Sandy-driven flooding in the tri-state area, while accounting for natural land subsidence and all-natural components of ocean warming. A damage model was used to develop a range of dollar value estimates attributable to damages caused by anthropogenic sea level rise, with $8.1 billion representing the central estimate.

In the future, the researchers hope to apply this approach to assessing the financial and human costs of human-caused sea level rise to other regions, including the Gulf of Mexico.

"If we were to calculate the costs of climate change across all flooding events - both nuisance floods and those caused by extreme storm events - that figure would be enormous," said Orton. "It would provide clarity on the severe damage we are inflicting on ourselves and our planet."

BOSTON - Prompted by a recent alarming rise in cases of colorectal cancer in people younger than 50, an independent expert panel has recommended that individuals of average risk for the disease begin screening exams at 45 years of age instead of the traditional 50.

The guideline changes by the U.S. Preventive Services Task Force (USPSTF), published in the current issue of JAMA, updates its 2016 recommendations and aligns them with those of the American Cancer Society, which lowered the age for initiation of screening to 45 years in 2018.

Colorectal cancer (CRC) is one of the most preventable malignancies, owing to its long natural history of progression and the availability of screening tests that can intercept and detect the disease early. Overall incidence of CRC in individuals 50 years of age and older has declined steadily since the mid-1980s, largely because of increased screening and changing patterns of modifiable risk factors.

"A concerning increase in colorectal cancer incidence among younger individuals (ie, younger than 50 years; defined as young-onset colorectal cancer) has been documented since the mid-1990s, with 11% of colon cancers and 15% of rectal cancers in 2020 occurring among patients younger than 50 years, compared with 5% and 9%, respectively, in 2010," said Kimmie Ng, MD, MPH, first author of an editorial in JAMA accompanying the article about the guideline change of the USPSTF. Ng is the director of the Young-Onset Colorectal Cancer Center at Dana-Farber Cancer Institute.

The causes of the increase in young-onset CRC aren't currently known.

Lowering the recommended age to initiate screening "will make colorectal cancer screening, which is so important, available to millions more people in the United States, and hopefully many more lives will be saved by catching colorectal cancer earlier, as well as by preventing colorectal cancer," said Ng.

The USPSTF is an independent panel of experts funded by the U.S. Department of Health and Human Services. It systematically reviews the evidence of effectiveness of preventive services and develops recommendations. American health insurance groups are required to cover, at no charge to the patient, any service that the USPSTF recommends with a grade A or B level of evidence, regardless of how much it costs.

The task force recommendation means that insurers will be required to cover preventive procedures such as colonoscopies and stool tests designed to detect colon cancer in early stages.

The task force selected age 45 based on research showing that initiating screening at that age averted more early deaths than starting at age 50, with a relatively small increase in the number of colonoscopy complications. There is no change to the USPSTF 2016 recommendation to only selectively screen individuals aged 76 to 85, as research shows only small increases in life-years gained.

The accompanying JAMA editorial asked rhetorically whether the age of screening should be lowered even younger than age 45. While the majority of young-onset CRC diagnoses and deaths occurs in persons 45 to 49, the rate of increase in young-onset CRC is actually steepest in the very youngest patients. Colon cancer incidence is increasing by 2% per year in 20 to 29-year-olds, compared with 1.3% in 40 to 49-year-olds. Rectal cancer incidence is increasing by 3.2% per year in 20 to 29-year-olds and 30 to 39-year-olds, versus 2.3% in 40 to 49-year-olds.

"We are now seeing patients even younger than 45 - in their 20s and 30s - who are being diagnosed with this cancer and often at very late stages," said Ng. "Clearly the USPSTF recommendation to start screening at age 45 will not be enough to catch those young people who are being diagnosed."

Ultimately, optimal prevention and early detection of CRC in people younger than 45 will require further research into the underlying causes and risk factors of young-onset
CRC, which have thus far remained elusive, said the editorial authors.

The authors also called for "bold steps" to translate the lowered age of beginning screening into meaningful decreases in CRC incidence and mortality, noting that despite the preventive benefits of colorectal cancer screening, only 68.8 percent of eligible individuals in the United States undergo screening. The rate is lower among the uninsured and underinsured, those with low incomes, and racial and ethnic minorities. Barriers include lack of knowledge of the importance of screening, concerns about the invasive nature of colonoscopy, and lack of access to and provider recommendations for screening.

The editorial lists examples including public awareness campaigns, including those aimed at gaps in CRC incidence and mortality between Black and white Americans, and specific actions. Employers could provide 45-year-old employees with a paid "wellness day" to undergo CRC screening, or offer day care or transportation vouchers to overcome the logistical hurdles of colonoscopies. Health systems could offer weekend or after-hours appointments for colonoscopies.

The new recommendation "represents an important policy change," the authors wrote, "to drive progress toward reducing colorectal cancer incidence and mortality."

Scientists led by Dr. Salvador Aznar-Benitah, head of the Stem Cells and Cancer laboratory at IRB Barcelona, have described the alterations that occur during mammary gland formation when heterochromatin (the part of DNA that does not actively produce proteins) is poorly regulated. The results, which have been published in the journal Cell Stem Cell, indicate that incorrect DNA packaging makes retrotransposons (a type of transposable element originated in ancestral fragments of viruses integrated into the cell genome) more accessible.

As these fragments are more accessible, they can be "read" and copied by the cellular machinery. The cell reacts to the presence of these viral fragments as if it was undergoing infection and it triggers an immune response through a cellular program called pyroptosis. As a result, the interactions between different cells are altered within the breast, leading to complete failure to performs its primary function of milk secretion.

"In many types of cancer, such as triple-negative breast cancer, we observe that there are regions of the genome that are unexpectedly unfolded and we need to understand the implications. The inflammatory response and the alterations that arise could play a key role in the ability of these cells to colonise other organs, causing what is known as metastasis," explains Dr. Aznar-Benitah, ICREA researcher at IRB Barcelona.

The importance of DNA folding

The main function of the DNA in our cells is to coordinate the production of proteins responsible for executing cellular functions. However, some parts of the genome are tightly condensed and thus are not used for this purpose. This study and others published by the scientific community report that proper regulation of chromatin condensation is also key for the correct development of tissues.

The non-coding DNA of animals contains transposable elements, which are ancestral viruses that integrated into the genome a long time ago. If these elements are "read" and copied by the cellular machinery, it is detrimental for the cell. Therefore the cell has evolved mechanisms to protect itself. One of the mechanisms that prevents retroviral copying in healthy cells is chromatin compaction. In their recent work, Dr. Aznar-Benitah and colleagues demonstrated that disrupting this compaction and releasing these ancestral viruses is not only detrimental to the individual cell but has repercussions on the function of the whole tissue (and maybe even the organism).

Bringing research closer to clinical practice

Dr. Alexandra Avgustinova, first author of the article and IRB Barcelona Alumna, has now set up her own laboratory in the Paediatric Cancer programme at the Institut de Recerca Sant Joan de Déu (IRSD). Her group addresses the regulation of the genome at the onset of paediatric cancer and, in this context, will study the influence of transposable elements like retrotransposons in the responsiveness of paediatric cancers to immunotherapy.

"I learnt a lot during my years at IRB Barcelona and had the opportunity to meet outstanding scientists with whom I would like to collaborate in the future. Working with Salva has taught me to "think big" and really pursue the questions that intrigue me, which will be very important when it comes to heading your own group!" says Dr. Avgustinova.

Techniques developed and future lines of study

To carry out this research, scientists from IRB Barcelona's Stem Cell and Cancer laboratory have had to develop a very complex study model: They employed computational tools capable of identifying the transposable elements that are being copied within a cell, in combination with a mouse model in which they could assess the functional consequences of disrupting chromatin compaction.

This study demonstrates that disrupting chromatin compaction can have repercussions that reach beyond the affected cell, and it paves the way for research into the metastatic processes of tumours with altered chromatin compaction and thus deregulation of transposable elements.

Fossils of land animals from South America have been found in the Antilles, but how did these animals get there? According to scientists from the CNRS, l'Université des Antilles, l'Université de Montpellier and d'Université Côte d'Azur, land emerged in this region and then disappeared beneath the waves for millions of years, explaining how some species were able to migrate to the Antilles. This study will be published in June 2021 issue in Earth-Science Reviews.

Fossils of land animals from the Antilles, including mammals and amphibians, have their closest relatives in South America. The crossing of the Caribbean Sea from South America was therefore possible, but how?

As swimming across the continent must be ruled out, given that several hundred kilometres separate the South American continent from the Antilles, the dispersal of this fauna has been attributed either to natural rafts coming out of the continent's flooded rivers, or to the existence of land bridges that are now submerged.

A scientific project involving geologists, palaeontologists and geophysicists1 is now solving some of the mysteries related to these terrestrial species in the Antilles. The researchers have reconstructed the geography of the northern Lesser Antilles over the last 40 million years and have shown that the movements of the tectonic plates at the junction between the Lesser Antilles, the Greater Antilles and the Aves Ridge (an underwater mountain), have several times given birth to archipelagos and islands quite close to each other, which were then swallowed up in the course of time.

In addition to tectonic movements, the glacial-interglacial cycles for 1.5 million years (Quaternary) have favoured the appearance and disappearance of archipelagos. Indeed, during these cycles, the sea level decreases or increases according to the storage of water in the ice caps or their melting (the duration of these cycles is about 100,000 years). The formation of these archipelagos could thus have favoured terrestrial connections between the Aves Ridge, the Greater Antilles and the Lesser Antilles.

Scientists will now extend their studies southward, between Guadeloupe and South America, to reconstruct the past geography of the entire Caribbean Plate, in order to define more precisely the nature of the terrestrial species' dispersal paths between the Americas.

A University of Surrey project has revealed innovative methods that could dramatically improve the performance of future electrical vehicles (e-vehicles).

As part of the European Union's STEVE* project, Surrey has developed several pioneering approaches to torque vectoring in electric vehicles.

In e-vehicles with multiple motors, it is possible to deliver different amounts of drive power to each wheel. This benefits the vehicles' power consumption, safety and driveability. The process of calculating and optimising the precise amount of power needed while the vehicle moves is complex; it requires detailed knowledge of the driving conditions ahead and powerful onboard computing resources to deliver the data in real-time - often making the techniques impractical for everyday vehicles.

The team from Surrey has revealed advanced methods to improve torque vectoring that can be implemented in consumer e-vehicles.

For example, to improve the safety of e-vehicles, the team created a stability-control system that anticipates the curvature of the road ahead, allowing the car to pre-emptively brake when it approaches a bend too fast.

Surrey's torque vectoring system combines a predictive control model with fuzzy logic to adaptively prioritise vehicle dynamics or energy efficiency, depending on the driving conditions. The team has shown that their model developed to simulate the way a vehicle is driven, using the so-called 'pulse and glide' approach to reduce energy consumption, is beneficial in electric vehicles and is cost-effective enough to be implemented in future e-vehicles.

The project is part of a EUR 9.5 million European Commission project, bringing together 20 partners from across the continent to envision and create a new concept in urban mobility. The project, which started in 2017, was completed in April 2021 and published various findings alongside a series of real-world demonstrations.

Professor Aldo Sorniotti, Head of the Centre for Automotive Engineering at the University of Surrey, said: "This has been an exciting project that has allowed us to make some major advances in powertrain control for electric vehicles. We believe that our work will allow new advanced torque vectoring techniques to become useable in ordinary electric vehicles, delivering research that will directly assist drivers in the very near future."

Riccardo Groppo, CEO of Ideas & Motion, one of the project partners, said: "It has been a pleasure working with the University of Surrey on the STEVE project. In particular, the technical collaboration was fundamental to making progress on the inverter and control algorithm for the Light Electric Vehicle we developed. I think we have accomplished excellent results, setting the basis for further collaboration."

To support growing human and animal life, freshwater sources must continuously supply water. Freshwater from lakes, rivers, and underground is mainly recharged by rainfall. Ground reservoirs can store rainwater over time, depending on that location's storage capability. However, estimating freshwater storage capability (FSC) is still a challenge due to few observation opportunities and methods to measure and quantify FSC.

Prof. Xing Yuan and his Ph.D. student Enda Zhu, from the Institute of Atmospheric Physics at the Chinese Academy of Sciences, developed and applied a new metric that characterizes the "inertia" of water after rainfall. This method allows better FSC analysis based on satellite data from the Gravity Recovery and Climate Experiment (GRACE). Researchers simulated their new algorithm using the Community Land Model version 5 (CLM5) for 194 major river basins around the world. Advances in Atmospheric Sciences has accepted the study, its results, and supporting data.

"The FSC of river basins which displays the proportion of precipitation that can be retained in land is closely related with the hydrological memory." said Prof. Yuan. "Larger FSC means longer hydrological memory, which will have an impact on local and regional weather and climate through the land-atmosphere couple."

Results show that, on average, global land surfaces can retain over one quarter of monthly precipitation based on GRACE observation. The CLM5 simulation represents a similar global distribution. Using this new metric, Small FSC areas have wetter conditions and a higher vegetation density, whereas large FSC areas have drier climates.

This metric observes evaporation using satellite observations. Compared with the monthly FSC, the amount of water retained within land is higher at a shorter time scale due to less evaporation in low FSC areas. Across multiple time scales, the root zone contributes to about 40% of the global land FSC.

While this study, published in Advances in Atmospheric Sciences, primarily focuses on rainfall, precipitation that falls as snow is important, despite most frozen water content sitting above the ground surface. Snow contributes to more than 20% of land FSC, especially in high latitudes.

"This work is worthy of further attentions for water resources management and hydrological prediction," explained Prof. Yuan.

May 18, 2021 - Offering interventions to young people in the general community can prevent the emergence of certain mental health disorders, according to the first comprehensive systematic review to address this question. The results appear in the May/June issue of Harvard Review of Psychiatry, which is published in the Lippincott portfolio by Wolters Kluwer.

"Preventive interventions for poor mental health outcomes in young people are feasible and appear to be effective," according to the review by Gonzalo Salazar de Pablo, MD, and Andrea De Micheli, MD, of King's College London, and colleagues. Evidence suggests that young people respond well to early interventions.

Universal and selective interventions reduce risk of most mental disorders
The researchers systematically reviewed decades of medical literature and found 295 studies in which individuals under 35 years old were randomly assigned to a mental health preventive intervention or a control group. Most studies examined psychoeducation (37 percent) or psychotherapy (28 percent), whereas 18 percent explored both and 17 percent involved other types of interventions.

Forty percent of the studies investigated universal interventions, which target a general population - for example, a high school assembly about alcohol use is a universal intervention. Other studies focused on selective interventions, which target symptom-free individuals who are considered at high risk of developing a mental disorder. Seventy percent of the studies were conducted in North America or Europe.

All told, 447,206 young individuals participated: 234,330 in intervention groups and 212,876 in control groups. The average age of the participants was 15 years, but they ranged from infants under 1 year to adults 34 years old.

The researchers combined the results of all studies using a statistical process called meta-analysis. Compared with control conditions, the 17 mental health disorders studied fell into three groups:

Risk reduced by both universal and selective prevention measures: affective (mood) symptoms, alcohol use and its consequences, anxiety features, conduct problems, interpersonal violence, general psychological distress, posttraumatic stress disorder, tobacco use, and "other" emotional and behavioral problems

Risk marginally reduced by both universal and selective prevention measures: attention-deficit/hyperactivity (ADHD) features, cannabis use, and externalizing behaviors (e.g., aggressive or antisocial)

Risk not reduced by either universal or selective prevention measures: eating-related problems, impaired functioning, internalizing behaviors (e.g., fearful, anxious, or inhibited), and sleep-related problems

Psychoeducation interventions were particularly promising for ADHD features, affective symptoms, or interpersonal violence. Psychotherapy was most effective for anxiety features.

Even for interventions that showed some ability to prevent mental health problems, the effect sizes (the magnitude of the improvements) were small. However, Dr. Salazar de Pablo, Dr. De Micheli, and colleagues note: "Since these samples are typically young and not yet affected by psychiatric conditions, small effect sizes...can potentially translate into relevant benefits in the longer term--if the intervention is provided to enough individuals."

As lockdown measures ease this week in the UK, environmental psychologists are urging that before rushing back to business as normal, we take advantage of the shifts observed over the past year to lock-in new, greener behaviours.

Writing in the journal Current Opinion in Psychology, the team from the Centre for Climate Change & Social Transformations (CAST) from the University of Bath and Cardiff, suggest that environmental interventions aimed at reducing our emissions should be targeted at times when habits are weakest and most malleable to change.

Their work draws on the idea of 'habit discontinuity' whereby major changes in our lives can provide a window of opportunity to change behaviours. This work initially focused on the impact of life events, such as house moves, and the effect this could have on changing individuals' commuting behaviours (e.g. cycling to work instead of driving). This effect is said to last for just three months before habits become ingrained again.

In their article, the research team focus on priority areas where personal actions are necessary to reduce our emissions in line with the UK's net zero target. These include flying - currently the highest carbon emitting activity - and eating less red meat and dairy.

Surveys conducted by CAST throughout the pandemic highlighted that UK lockdowns had significantly reduced individuals' carbon footprints with people buying and travelling much less. Additionally, the impact of the pandemic appears not to have dented individuals' willingness to take climate action.

Recent polling from IPSOS-Mori with CAST, suggest that the UK public are willing to take significant action to climate change with almost three-quarters agreeing with the statement: 'if individuals do not act now to combat climate change, we will be failing future generations'.

Director of the Centre for Climate Change & Social Transformations, Professor Lorraine Whitmarsh from the University of Bath explains: "COVID-19 represents the most significant disruption to lifestyles since the Second World War - people have been working, consuming and interacting in new ways, many of which are good for the climate and could also improve wellbeing. As lockdown eases, employers, city leaders, and government now need to implement measures that will lock in these positive behaviours, to enable a green recovery rather than a return to business as usual."

Co-author, Dr Stuart Capstick Research Fellow from the School of Psychology at Cardiff University adds: "I hope that we can apply some of the lessons from a very difficult year to help tackle the climate emergency too. All of us have had to get used to the idea that our own actions matter for the health and wellbeing of other people. When it comes to reducing emissions and bringing about low-carbon ways of life, there are important parallels here and a need to take our own part in that seriously."

Climate change-induced ice melting in the Arctic has led to contradictions in the assessment of Russia's rights in the region. As ice cover diminishes, Russia may be losing its influence on the territories that it has historically developed. This is partially due to the changing width of territorial waters by low-water lines. However, there are alternative legally valid ways to establish fair borders, which are described by researchers of the HSE Institute of Ecology in their paper 'Prospects for the evolution of the system of baselines in the Arctic' https://www.mdpi.com/2073-4441/13/8/1082/htm.

Baselines are one of the key factors shaping international maritime law. From these lines the breadth of a territorial sea is measured, over which the sovereignty of a coastal state extends. The outer boundary of a territorial sea is its maritime boundary. Baselines are also used to measure the width of exclusive economic zones and continental shelfs, where the coastal state has broad sovereign rights or jurisdiction. 'The issue of optimal baseline outlining is very important for ensuring the sovereignty, sovereign rights, and national security of any coastal state,' said Boris Morgunov https://www.hse.ru/en/org/persons/156593647, Director of the HSE Institute of Ecology https://eco.hse.ru/en/.

According to the UN Convention on the Law of the Sea, there are two types of baselines for measuring the width of territorial sea: normal baselines and straight baselines. A normal baseline is the maximum low-water line along the coast, which is outlined on large-scale sea maps that are officially recognized by the coastal state. This means that if the coastal line is very long, an extremely high volume of hydrographical and cartographical work is required to adjust the maps. Speaking of which, Russia has the longest coastline in the Arctic Ocean.

Meanwhile, the same UN Convention says that 'in localities where the coastline is deeply indented and cut into, or if there is a fringe of islands along the coast in its immediate vicinity, the method of straight baselines joining appropriate points may be employed in drawing the baseline from which the breadth of the territorial sea is measured'. Straight baselines are also drawn in localities where the coastline is highly unstable, such as river deltas. In addition, 'economic interests peculiar to the region concerned' may be taken into account, if their 'reality and importance are clearly evidenced by long usage'.

The system of baselines that is currently used in Russia was established by the Order of the USSR Council of Ministers of January 15, 1985, which stipulates the 'List of Geographical Coordinates of Points that Determine the Position of Baselines to Measure the Width of Territorial Waters, Economic Zones and the Continental Shelf of the USSR'. This system uses a combination of straight and normal baselines. However, due to decreasing areas of perennial ice in the Arctic Ocean and natural processes that bring the sea closer to the coast in Russia's Arctic seas, the configuration of the Russian coastline has considerably changed since 1985. For example, in the Laptev Sea, the rate of coastal erosion can reach 30-55 meters annually, which has led to the extinction of three islands within several decades. It is expected that climate change will accelerate these processes many times.

The paper authors say that the Russian scientific community has long raised the issue about the need to review the 1985 List. International law does not limit the ability of coastal states to amend previously approved baselines. Many states have executed this right, including Arctic ones, such as Norway and Denmark, which delineated their coasts with straight baselines, thereby receiving a number of advantages.

Another way to reinforce Russia's position in the Arctic could be granting the Russian territorial waters historic water status. The concept of 'historic waters' is used in international practice, although it is not clearly enough formulated in legal terms. Such a status can be granted in case of permanent and long-term use of these waters. This is possible if the other states do not object or pose obstacles to the process.

Researchers from the HSE Institute of Ecology believe that Russia has basis to consider granting historic water status to some additional Arctic water zones. Russia has developed the Arctic coast and adjacent sea areas for a long time (several centuries). In the 16th-17th centuries, the north of Siberia was developed by the Cossacks. Since the 18th century, state expeditions explored Russia's northern borders and the adjacent sea areas. The Great Northern Expedition (1733-1743), which consisted of several parties, played a particular role in these explorations.

In the 19th-20th centuries, Russian researchers carried out multiple scientific expeditions, which discovered new islands and straits, created new maps, and went on outstanding boat trips on Arctic routes. Particularly, in 1913, an expedition led by Boris Vilkitsky discovered Severnaya Zemlya archipelago -- the last big part of land discovered on our planet.

Since the 16th century, Russia has confirmed its legal claims on the Northern lands and seas on the state level. Tsar Ivan the Terrible officially denied England's application to provide an exceptional right for trade in the mouths of the Northern rivers, emphasizing that 'those areas are in our land... of three thousand versts' (a verst was a Russian unit of distance equal to 1.067 km). Particularly justifying Russia's rights on areas in the Arctic Ocean is the Circular Note of the Russian Ministry of Foreign Affairs of September 20, 1916, in which the Government of the Russian Empire informed foreign states that it includes the lands discovered by Russian Polar expeditions in the Arctic in its territory.

The authors emphasize that the sea areas adjacent to Russia's Arctic coast have never been used for economic development by foreign states or for international navigation. On the contrary, they served as an important source of marine biological resources for coastal communities, primarily small indigenous populations, as well as for the entire population of the country. In the 20th century, economic development of Russia's Arctic areas got a big boost. The economy of the Arctic zone of the Russian Federation is inextricably connected with the Northern Sea Route. The scale and growth rates of maritime shipping on the Northern Sea Route are confirmed by the following figures: the total volume of shipped cargo was about 1.6 million tons in 2000 and 26 million tons in 2019. By 2024, it is forecasted to reach 80 million tons.

'The new geographical coordinates of the baselines of contemporary Russia's Arctic coast should not be an "adjusted" version of the 1985 List,' said Boris Morgunov. 'This specification should be innovative and clearly reflect the current balance of reviewed sea borders at all levels, and it should be consistent with the practices of other Arctic states that draw straight baselines in the Arctic. We should also consider the long history of scientific and economic developments in the Russian Arctic.'

Climate change induced yield reductions can be compensated by cultivar adaptation and global production can even be increased.

Global agriculture both is one of the major drivers of climate change and strongly affected by it. Rising temperatures are among the main reasons for yield reductions. Therefore, the agricultural sector is faced with the major challenge of adapting to climate change in order to ensure food security in the future. According to a new study carried out by international researchers, the use of locally adapted cultivars can significantly contribute to achieve this goal. The study was led by LMU geographer Dr. Florian Zabel.

For four different climate scenarios, he and his colleagues simulated the impacts of climate change on the global production of maize, rice, soy and wheat and investigated how locally adapted cultivars would affect crop yields. Thereby, the scenarios represent different socio-economic pathways that result in temperature increases ranging between 1.4 and 3.9°C in global average.

"Our results show that, at least under moderate warming, we could generally adapt well to climate change and even increase global yields by almost 20% until the end of the century. Thereby, the increase of atmospheric CO2 partly attributes to the yield increase for some crops, due to positive effects on the efficiency of photosynthesis." says Zabel.

Strong warming threatens adaptation

If global warming can be restricted to below 1.5°C, as specified in the Paris Agreements, the simulations suggest that 85% of the global cropland area can be optimally cultivated with already available cultivars.

The stronger the warming, the more new cultivars will be needed and the higher the risk that a required locally adapted cultivars that can cope with the changed local conditions will not be available.

"In the worst-case scenario, almost 40% of global cropland could require new cultivars, of which some would need to have traits that currently do not exist," says Zabel. Thereby, a critical point is that this even affects globally important production regions, such as North America's Corn Belt, the world's most important region for maize production.

"In addition, there are some regions where cultivar adaptation will not be possible, for instance due to a change in future precipitation and possible droughts," says Zabel. The simulations consider local and regional effects of climate change, and therefore allow identifying regions where locally adapted cultivars could be particularly beneficial for yields. These include large areas of Europe, China and Russia. However, in other parts of the world - including Turkey, Northeastern Brazil, Texas, Kenya and parts of India - adapted cultivars are predicted to have little or no effect on yields, due to a reduction of available water for crops.

Innovative and more efficient breeding methods offer a possible solution. "Conventional breeding approaches often take years," Zabel points out. "New methods such as CRISPR-Cas could help to develop required cultivars that are specifically adapted to local conditions more quickly and in a more targeted way," Zabel adds.

In the midst of a devastating global pandemic of wildlife origin and with future spillovers imminent as humans continue to come into closer contact with wildlife, infectious-disease models that consider the full ecological and anthropological contexts of disease transmission are critical to the health of all life. Existing models are limited in their ability to predict disease emergence, since they rarely consider the dynamics of the hosts and ecosystems from which pandemics emerge.

Published May 17 in Nature Ecology and Evolution, Smithsonian scientists and partners provide a framework for a new approach to modeling infectious diseases. It adapts established methods developed to study the planet's natural systems, including climate change, ocean circulation and forest growth, and applies them to parasites and pathogens that cause disease.

Increased human-animal interactions lead to the emergence and spread of zoonotic pathogens, which cause about 75% of infectious diseases affecting human health. Predicting where, how and when people and animals are at risk from emerging pathogens--and the best ways to manage this--remains a significant challenge. Risks for spillover include, but are not limited to, habitat encroachment, illegal wildlife trade and bush meat consumption.

Despite incredible advances in the understanding of how infectious diseases are transmitted, the models these efforts are based on are relatively limited in scope, focusing on specific pathogens and often overlooking how pathogens interact within their hosts. While scientists and global health organizations are putting a lot of effort into studying the diversity of disease-causing organisms, existing models do not link this diversity to their roles within ecosystems.

"Just as a mechanic must understand how a car's components interact and how it's been engineered in order to improve performance, the same applies to our ability to model infectious disease," said first author Dr. James Hassell, wildlife veterinarian, epidemiologist and Keller Family Skorton Scholar for the Smithsonian Conservation Biology Institute's (SCBI) Global Health Program. "Applying systems-level thinking to forecast disease emergence requires a fundamental change in how we conceptualize infectious diseases. This presents significant challenges, but in this article, we explain why they're not insurmountable. When you weigh the cost of prevention versus remediation, the investment in our shared global health, particularly the connections between nature and human health, is vital."

Researchers say this new model will require expertise and collaboration across fields such as veterinary and human medicine, disease ecology, biodiversity conservation, biotechnology and anthropology.

"Disease and health are predominantly viewed as a human construct and the role the environment plays in disease is often overlooked," said Yvonne-Marie Linton, research director for the Walter Reed Biosystematics Unit for the Smithsonian's National Museum of Natural History and Walter Reed Army Institute of Research. "The health of other organisms, from parasites and insects to birds and aquatic organisms, can alter the structure of ecosystems. What we're proposing is a new approach to modeling infectious diseases that are circulating in nature, which would allow scientists to simulate the behavior of these pathogens in wildlife populations, how they respond to human activities and better determine the risk that they pose to people."

General ecosystem models are essentially complex models that can predict how food chains are assembled--the processes of energy transfer between plants and animals are what structure ecosystems--and determine the plants and animals that compose an ecosystem. With the new version, general "episystem" models, the paper's authors outline a framework for integrating disease agents (including parasites, viruses and bacteria) into these models. By identifying general rules for how food chains that include disease entities are structured, it should be possible to predict the types of pathogens that are present in any given ecosystem. This would allow scientists to better understand the characteristics of an ecosystem (such as disturbance) that would make it more likely to contain zoonotic pathogens, predict the threat it poses to people who interact with this ecosystem and even permit computer simulation and testing of interventions aimed at reducing these threats.

While the amount of data that would be required to create these models is daunting, long-term studies of intact ecosystems where parasite data has been collected are excellent places to initiate these studies. Efforts to refine them more broadly could then leverage large-scale ecological studies that span continents such as the Smithsonian's ForestGEO and MarineGEO programs.

The potential impacts of this new model go beyond reducing the human interface for disease spillover, to economics. "You could use this new approach to not only to look at human diseases, but also to look at the best way to conduct aquaculture or raise healthy livestock," said Katrina M. Pagenkopp Lohan, a marine disease ecologist at the Smithsonian Environmental Research Center. "If you're reintroducing a species into the wild, what do you need that ecosystem to look like for you to be successful? We could actually model that. It's mind blowing."

The cost of such a new approach is considerable, say researchers, and will take the global cooperation and commitment of scientists, communities, non-governmental organizations and nations. In an era of big data and massive advances in technology, this kind of approach is achievable but requires enhanced data collection, sharing and testing at far greater scales than currently occur.

A new study of ancient DNA from horse fossils found in North America and Eurasia shows that horse populations on the two continents remained connected through the Bering Land Bridge, moving back and forth and interbreeding multiple times over hundreds of thousands of years.

The new findings demonstrate the genetic continuity between the horses that died out in North America at the end of the last ice age and the horses that were eventually domesticated in Eurasia and later reintroduced to North America by Europeans. The study has been accepted for publication in the journal Molecular Ecology and is currently available online.

"The results of this paper show that DNA flowed readily between Asia and North America during the ice ages, maintaining physical and evolutionary connectivity between horse populations across the Northern Hemisphere," said corresponding author Beth Shapiro, professor of ecology and evolutionary biology at UC Santa Cruz and a Howard Hughes Medical Institute investigator.

The study highlights the importance of the Bering Land Bridge as an ecological corridor for the movement of large animals between the continents during the Pleistocene, when massive ice sheets formed during glacial periods. Dramatically lower sea levels uncovered a vast land area known as Beringia, extending from the Lena River in Russia to the MacKenzie River in Canada, with extensive grasslands supporting populations of horses, mammoths, bison, and other Pleistocene fauna.

Paleontologists have long known that horses evolved and diversified in North America. One lineage of horses, known as the caballine horses (which includes domestic horses) dispersed into Eurasia over the Bering Land Bridge about 1 million years ago, and the Eurasian population then began to diverge genetically from the horses that remained in North America.

The new study shows that after the split, there were at least two periods when horses moved back and forth between the continents and interbred, so that the genomes of North American horses acquired segments of Eurasian DNA and vice versa.

"This is the first comprehensive look at the genetics of ancient horse populations across both continents," said first author Alisa Vershinina, a postdoctoral scholar working in Shapiro's Paleogenomics Laboratory at UC Santa Cruz. "With data from mitochondrial and nuclear genomes, we were able to see that horses were not only dispersing between the continents, but they were also interbreeding and exchanging genes."

Mitochondrial DNA, inherited only from the mother, is useful for studying evolutionary relationships because it accumulates mutations at a steady rate. It is also easier to recover from fossils because it is a small genome and there are many copies in every cell. The nuclear genome carried by the chromosomes, however, is a much richer source of evolutionary information.

The researchers sequenced 78 new mitochondrial genomes from ancient horses found across Eurasia and North America. Combining those with 112 previously published mitochondrial genomes, the researchers reconstructed a phylogenetic tree, a branching diagram showing how all the samples were related. With a location and an approximate date for each genome, they could track the movements of different lineages of ancient horses.

"We found Eurasian horse lineages here in North America and vice versa, suggesting cross-continental population movements. With dated mitochondrial genomes we can see when that shift in location happened," Vershinina explained.

The analysis showed two periods of dispersal between the continents, both coinciding with periods when the Bering Land Bridge would have been open. In the Middle Pleistocene, shortly after the two lineages diverged, the movement was mostly east to west. A second period in the Late Pleistocene saw movement in both directions, but mostly west to east. Due to limited sampling in some periods, the data may fail to capture other dispersal events, the researchers said.

The team also sequenced two new nuclear genomes from well-preserved horse fossils recovered in Yukon Territory, Canada. These were combined with 7 previously published nuclear genomes, enabling the researchers to quantify the amount of gene flow between the Eurasian and North American populations.

"The usual view in the past was that horses differentiated into separate species as soon as they were in Asia, but these results show there was continuity between the populations," said coauthor Ross MacPhee, a paleontologist at the American Museum of Natural History. "They were able to interbreed freely, and we see the results of that in the genomes of fossils from either side of the divide."

The new findings are sure to fuel the ongoing controversy over the management of wild horses in the United States, descendants of domestic horses brought over by Europeans. Many people regard those wild horses as an invasive species, while others consider them to be part of the native fauna of North America.

"Horses persisted in North America for a long time, and they occupied an ecological niche here," Vershinina said. "They died out about 11,000 years ago, but that's not much time in evolutionary terms. Present-day wild North American horses could be considered reintroduced, rather than invasive."

Coauthor Grant Zazula, a paleontologist with the Government of Yukon, said the new findings help reframe the question of why horses disappeared from North America. "It was a regional population loss rather than an extinction," he said. "We still don't know why, but it tells us that conditions in North America were dramatically different at the end of the last ice age. If horses hadn't crossed over to Asia, we would have lost them all globally."

SAN DIEGO (May TK, 2021) - Compared to most other bear species, very little is known about how female Andean bears choose where they give birth to cubs. As a critical component of the reproductive cycle, birthing dens are essential to the survival of South America's only bear species, listed as Vulnerable on the International Union for Conservation of Nature (IUCN) Red List of Threatened Species.

A new study led by Russ Van Horn, Ph.D., published April in the journal Ursus, takes the most detailed look yet at the dens of this species. Van Horn, a population sustainability scientist, leads San Diego Zoo Wildlife Alliance's Andean bear conservation program. He was joined by colleagues from the University of British Columbia's Department of Forest and Conservation Sciences and the Spectacled Bear Conservation Society. The study's findings may aid conservation planners in locating den sites or guiding management for suitable bear habitat.

"The characteristics that seemed to influence the use of sites for dens can be measured and modeled by spatial ecologists, facilitating plans to manage human activities where females may choose to give birth," said Van Horn.

The scientists examined eight dens used by female bears between 2008 and 2013 in the equatorial dry forest of Cerro Venado (pronounced Ser-o Ven-ah-doe) in Northwest Peru. Prior to this study, just two Andean bear birthing dens had been formally described. The team accounted for a range of factors affecting the dens, such as how easy they might be for predators to enter, and characteristics of the surrounding environment, including the steepness of surrounding slopes, the proximity of human activities and the availability of food and water.

Though not conclusive, the data suggest some similarities among the dens. All were preexisting cavities shaped in the ground by rocks that were less than 16.4 feet (5 meters) from a cliff and on relatively steep terrain. Simply stated, the dens were generally located in steep, rugged spots that would be difficult for humans or other terrestrial mammals to access.

"Challenging topography makes these dens hard to find and study," Van Horn said. "But it also makes it less likely that humans will disturb Andean bear females with young cubs, providing them with a baseline level of protection."

Access to food and water, interior space and entrance size appeared not to be as important. Andean bears live in a wide variety of habitats and due to unique characteristics of the georgraphic region assessed in this study females' den choice may differ in other areas of their range.