Tech

A team of Spanish researchers have developed, at the laboratory level, a prototype of a new biosensor to help detect breast cancer in its earliest stages. One of the team coordinators has been Ramón Martínez Máñez, a professor at the Universitat Politècnica de València (UPV) and the scientific director of the Networking Biomedical Research Centre in Bioengineering, Biomaterials and Nanomedicine (CIBER BBN). The other one has been Ana Lluch, a Valencian oncologist, co-coordinator of the Breast Cancer Biology Research Group of the INCLIVA Health Research Institute of the Hospital Clínic de València, and a member of the Networking Biomedical Research Centre in Cancer (CIBERONC). Their work has been published in the journal ACS Sensors.

According to the latest data collected by the European Cancer Information System (ECIS), 34,088 new cases of breast cancer were diagnosed in 2020 in Spain. This type of tumour was then the most frequent among women in this country.

Currently, mammography is the most widely used standard technique for diagnosis, but it has some limitations, such as exposure to radiation, and lower sensitivity and specificity in young women with dense breast tissue. "Therefore, new diagnostic tools are needed to aid in the early detection of breast cancer. Our biosensor is along these lines," explains Ana Lluch.

The development of this biosensor falls within the field known as liquid biopsy, which helps detect the presence of cancer through a blood test. The mesoporous biosensor developed by the UPV-INCLIVA team is easy to use, low cost, and provides results in a very short time -between 30 and 60 minutes- from a sample of the patient's plasma.

The biosensor is composed of a nanomaterial -a nanoporous alumina- that facilitates the detection in plasma of miR-99a-5p microRNA, which is associated with breast cancer. Until now, this has been done by using complex and time-consuming techniques, which means that this system could not be used as a diagnostic tool in the clinical setting.

Martínez Máñez explains how their alternative diagnostic system works: the nanopores of the biosensor are loaded with a dye -rhodamine B- and sealed with an oligonucleotide. When interacting with the plasma sample, if the pore gates do not detect the presence of the microRNA, they remain closed; in contrast, in the presence of miR-99a-5p, the pore gates open and the dye is released. "The change in dye release can be correlated with either healthy or breast cancer patients," summarises Martínez Máñez.

Staff from the IIS La Fe Institute for Health Research, where the tests for the validation of the new biosensors have been carried out, and the Networking Biomedical Research Centre in Cancer (CIBERONC) have also participated in the development of this biosensor.

"The next step in our work will be validating our system in a larger group of patients," concludes Ramón Martínez Máñez.

MSU researcher is studying, raising awareness about the role of sex in the efficacy of vaccines that make use of nanomedicine.

If there's one take-home message for the general public about the coronavirus vaccines approved in the U.S., it's that they are remarkably effective.

But Michigan State University's Morteza Mahmoudi is raising awareness about an important subtlety: The vaccines developed by Moderna and Pfizer-BioNTech appear to work slightly better for men than for women.

Both vaccines use tiny orbs, or nanoparticles, to deliver their active ingredients to cells in our immune systems. For years, Mahmoudi has been studying how and why nanomedicines -- therapies that use nanoparticles -- can affect patients differently based on their sex and he believes this could be a factor with the vaccines.

The Johnson & Johnson vaccine has also drawn attention to sex differences because its rare blood-clotting side effect has affected predominantly women. The J&J vaccine, however, uses modified adenoviruses rather than nanoparticles to help teach our immune systems to fight off the coronavirus. That said, Mahmoudi has shown in earlier work that viruses can transfect the cells of men and women differently.

Now, he's focusing on the nanomedicine component. He's published three peer-reviewed papers calling attention to the role of sex in nanomedicine studies, both in general and as they relate to coronavirus vaccines.

"We need to monitor these sex differences and report them to the scientific community and the public," said Mahmoudi, an assistant professor in the Department of Radiology and the Precision Health Program. "It can be very helpful in developing future strategies and as we prepare for future threats."

To develop those future strategies, researchers must better understand what causes patients of different sexes to respond differently to nanomedicines, Mahmoudi said. To that end, Mahmoudi is advocating for systemic changes in how nanoparticles are used and studied in medicine with an article published May 20 in the journal Nature Communications.

In the article, he outlines four large challenges in researching the role of sex in nanomedicine performance along with strategies to mitigate them moving forward.

For example, researchers may not have sufficient resources to perform their studies in cells or other samples taken from men and women. Yet these researchers and others may still interpret their results as being equally applicable to all sexes. To prevent this from happening, Mahmoudi is calling for researchers to be more transparent and share sex-specific limitations of studies and conclusions.

"We need to be more careful about the science that gets out," Mahmoudi said. "We've witnessed that there has not been a robust consideration of sex in nanomedicine, but we need to consider sex because it is important."

Before the coronavirus pandemic, most of the research interest and funding in nanomedicine had been focused on its use in treating cancer. But nanomedicine's performance in this realm has been lackluster. Less than 15% of nanomedicines that have entered clinical trials made it through the final phase and none have proven to be better than the standard of care, Mahmoudi said.

In addition, he said, when nanomedicines are robustly studied in women, it's often because the therapies are being studied in diseases that mainly affect women, such as breast and ovarian cancers.

"Our analysis of the 41 completed clinical trial studies of therapeutic nanomedicine products revealed that 21 studies were stratified by sex because they concerned pathologies primarily found in females," Mahmoudi said. "Of the remaining 20 studies involving 851 males and 430 females, none provided sex-stratified results or indications."

Mahmoudi's team detailed these findings and more in an article published online on May 4 in the journal Advanced Drug Delivery Reviews.

Despite their shortcomings in cancer therapies, nanoparticles have been greatly effective in helping provide protection against the novel coronavirus. Yet there is still evidence that the vaccines work differently for men and women.

"On the one hand, the vaccines have been really good news for nanomedicine," Mahmoudi said. "But we didn't solve the problems that we saw with them in cancer treatments."

To be clear, the differences in vaccine efficacy are small, but they are measurable. In the case of the vaccine developed by the pharmaceutical company Moderna, clinical trials showed it was 95.4% effective at preventing COVID cases for men, compared with 93.1% for women. For the vaccine created by Pfizer and BioNTech, the numbers are 96.4% for men and 93.7% for women.

Both vaccines use nanoparticles based on lipids, which are fatty molecules that form tiny spheres in water, kind of like bubbles. The pharma companies then pack these tiny lipid-based particles with the vaccines' active ingredients and essentially use the nanoparticles as delivery vehicles to ship the vaccines' payloads to our immune cells.

Working with researchers at Sapienza University of Rome, Mahmoudi designed an experiment to test whether lipid-based nanoparticles could be a reason behind the difference in vaccine efficacy for men and women. The team published its results on May 13 in the journal Molecular Pharmacology.

The team added lipid-based nanoparticles with similarities to those used in the vaccines to blood samples taken from 18 patients, eight men and 10 women. The researchers then observed how well or how poorly immune cells within the blood adsorbed those nanoparticles. The team found a significant difference between men and women for one cell type called natural killer cells.

"These cells are responsible for finding other infected cells -- cells that are producing the virus -- and they can kill them," said Mahmoudi. "What we found is that natural killer cells respond to lipid-based nanoparticles in a sex-specific manner."

Namely, natural killer cells from female donors took up fewer nanoparticles than natural killer cells from men. Based on this model system, then, it is plausible that the immune systems of men and women would respond differently to the vaccine.

But Mahmoudi and his colleagues also showed that the difference could be eliminated by first putting the nanoparticles in a donor's plasma, the cell-free portion of their blood sample. Mahmoudi believes this because proteins in the plasma can bind to the lipid-based nanoparticles, giving the nanoparticle a biological coating or corona.

"I think of the corona as acting like a new passport for nanoparticles, it tells the cells how to respond to nanoparticles," he said.

What this suggests, then, is that if there are differences in the vaccines' performance based on a patient's sex, doctors and researchers should be able to do something about it. But they'll need more research and data to fully understand the cause of and remedies to these differences, Mahmoudi said. Thankfully, though, the data available to the community is growing every day.

"The clinical trials were performed with tens of thousands of patients. We know that the differences are there and that we need to monitor them," he said. "Now we have millions of people getting the vaccines. That's millions of data points. We need to go out there and get them."

In a time of a global crisis such as the ongoing COVID-19 pandemic, it is easy to note how people move through different phases to buckle up for such unprecedented and arduous times.

In the very beginning of the pandemic last year, we observed "an epidemic of fear", where it was all about the calamitous nature of a totally unknown virus and its worrying contagiousness and mortality rate. A few months later, with lockdown and restrictions already in place across the world, the fear was replaced by "an epidemic of explanations", where people even in their naivety, started to seek a sense of comfort by placing the blame on someone or something out of their control.

This is why a research team at the SWPS University of Social Sciences and Humanities and the Polish Academy of Sciences sought to figure out whether the government was indeed the main culprit for the spread of the COVID-19 pandemic in the eyes of the public. After all, it fitted best the role of an actor of higher authority, allegedly powerful enough to protect the community and resolve the issue at hand and provide the necessary comfort. In the meantime, it comes as an easy target to point a finger at for 'not doing enough'. On the other hand, the public could as well be explaining the situation with the virulence of the Coronavirus or with the irresponsible behaviour of others in the society. Regardless of the answer, the team was interested in understanding what's behind one's reasoning: was it their political views, well-being or emotions?

To test their hypotheses, the researchers chose to conduct their study in Poland: a country currently politically divided between Liberalism and Communitarianism, with the latter being the ruling party at the time of the survey, which took place between May and June 2020. A total of 850 Polish adults fully diversified in terms of gender, age, and education participated. The findings are now published in the open-access, peer-reviewed scientific journal Social Psychological Bulletin.

As a result, the study concluded that not only was it the government and the system that most of the participants attributed responsibility to for the COVID-19 incidence rates, but that the political views and party preferences of the participants played an incomparably more significant role in their responses than factors such as anxiety, stress and depression levels or overall self-reported well-being. In fact, amongst the mental health symptoms, the study found that only increased anxiety was statistically significantly related to the tendency to blame the government and its decisions. This could be explained by the fact that people experiencing higher anxiety levels are more likely to exaggerate external responsibility, note the scientists. Curiously, the more educated participants were found to be more likely to emphasise governmental responsibility.

Furthermore, the people with lebaral views who did not support the ruling communitarian party blamed the government to a higher degree than their counterparts, who would often place the responsibility for the spread of COVID-19 on non-governmental factors.

In their study, the research team uses several theories to explain this finding, including the Terror Management Theory, which notes that reminding people of their mortality induces an existential threat that also leads to an increased need for protection provided by worldview-based beliefs. On the other hand, the theories of attribution and social roles suggest that people see the 'adequate protection against epidemic' as part of the government's duties.

In conclusion, the authors remind that their observations during the survey are consistent with previous reports as a result of natural disasters.

"Citizens observe governmental activities during the epidemic period and evaluate government responsibility. In the light of the results of previous studies on the social perception of natural disasters, we think that this is a rather general phenomenon. Looking for an explanation of the epidemic effects, people tend to blame salient external causes," say the researchers.

Researchers have long been interested in finding ways to use simple hydrocarbons, chemicals made of a small number of carbon and hydrogen atoms, to create value-added chemicals, ones used in fuels, plastics, and other complex materials. Methane, a major component of natural gas, is one such chemical that scientists would like to find to ways to use more effectively, since there is currently no environmentally friendly and large-scale way to utilize this potent greenhouse gas.

A new paper in Science provides an updated understanding of how to add functional groups onto simple hydrocarbons like methane. Conducted by graduate students Qiaomu Yang and Yusen Qiao, postdoc Yu Heng Wang, and led by professors Patrick J. Walsh and Eric J. Schelter, this new and highly detailed mechanism is a crucial step towards designing the next generation of catalysts and finding scalable approaches for turning greenhouse gases into value-added chemicals.

In 2018, a paper published in Science described a mechanism for adding functional groups onto methane, ethane, and other hydrocarbons at room temperature using a cerium-based photocatalyst. The ability to use earth-abundant metals like cerium to create value-added chemicals was an exciting prospect, the researchers say. However, there were aspects of this study that Schelter and his group, who have been working with cerium for a number of years, wanted to understand more thoroughly.

"There were some things in the original paper that we thought were interesting, but we didn't necessarily agree with the conclusions based on the data that they were reporting," Schelter says. "We had an idea that what was happening in terms of the mechanism of the reaction, the steps that were involved and the catalyst that was operative for their chemistry, was different from what they were reporting."

To run the experiments and collect the data they would need to support a new hypothesis, Schelter and Walsh applied for a seed grant from the University of Pennsylvania's Vagelos Institute for Energy Science and Technology. This funding supported a new collaboration between Schelter and Walsh, allowing the researchers to purchase specialized equipment and hire Yu Heng Wang, a former Penn postdoc who is now an assistant professor at National Tsinghua University in Taiwan.

Thanks to the Vagelos Institute support, the Schelter and Walsh groups were able to combine their complementary expertise in inorganic and organic chemistry and to conduct experiments to obtain data required to propose a new mechanism. This included synthesizing new chemicals, studying reaction rates, looking at how the photocatalyst reacted with different isotopes, and computational analysis. The researchers also isolated the proposed reaction intermediate and were able to obtain its crystal structure, an additional challenge considering that many of the compounds in this study were highly air- and moisture-sensitive.

"We are using conventional techniques to understand the system better and to give a clear mechanism," Yang says about their approach. "Here, we are mostly using the inorganic perspective with different techniques to understand the mechanisms of the organic reaction. So, it's a collaboration of inorganic and organic perspectives to understand the mechanism."

After more than two years of work, the researchers were able to propose a revised mechanism that highlights the essential role of chlorine atoms. While the previous study implicated an alcohol-based intermediate, this latest study found that chlorine radicals, atoms with unpaired electrons that make them highly reactive, form a selective chemical "trap" in the photocatalyst that can give rise to different products.

"I think the hardest part was to understand why the reactivity was happening, and we had to approach that with some unconventional thinking of these intermediate complexes," says Walsh. "The behavior of the intermediates fits a pattern that people attribute to a radical based on oxygen, but in fact it's really a chlorine radical that's the active species, activating the alcohol to make it look like it's a radical derived from the alcohol."

Having a detailed understanding of this chemical reaction is a crucial step towards improving existing catalysts and making these and other chemical reactions more efficient. "In order to rationally develop the next generation of catalysts, we have to understand what the current generation is doing," says Walsh. "With this information, we and others can now build on this revised mechanism and reaction pathway to push the science forward."

And while there is more work to be done towards finding a fast, scalable reaction for methane transformation, having a detailed understanding of the mechanisms that drive this specific reaction is essential to both reducing greenhouse gas emissions and being able to use methane to create value-added products, the researchers say.

"Chemistry is at its most elegant when we can refine knowledge through expanded insight," says Schelter. "The contribution here is about getting the right model and using it to advance to the next generation of catalysts that will be even better than the current one."

HOUSTON - (May 20, 2021) - It's always good when your hard work reflects well on you.

With the discovery of the giant polarization rotation of light, that is literally so.

The ultrathin, highly aligned carbon nanotube films first made by Rice University physicist Junichiro Kono and his students a few years ago turned out to have a surprising phenomenon waiting within: an ability to make highly capable terahertz polarization rotation possible.

This rotation doesn't mean the films are spinning. It does mean that polarized light from a laser or other source can now be manipulated in ways that were previously out of reach, making it completely visible or completely opaque with a device that's extremely thin.

The unique optical rotation happens when linearly polarized pulses of light pass through the 45-nanometer film and hit the silicon surface on which it sits. The light bounces between the substrate and film before finally reflecting back, but with its polarization turned by 90 degrees.

This only occurs, Kono said, when the input light's polarization is at a specific angle with respect to the nanotube alignment direction: the "magic angle."

The discovery by lead author Andrey Baydin, a postdoctoral researcher in Kono's lab, is detailed in Optica. The phenomenon, which can be tuned by changing the refractive index of the substrate and the film thickness, could lead to robust, flexible devices that manipulate terahertz waves.

Kono said easy-to-fabricate, ultrathin broadband polarization rotators that stand up to high temperatures will address a fundamental challenge in the development of terahertz optical devices. The bulky devices available until now only enable limited polarization angles, so compact devices with more capability are highly desirable.

Because terahertz radiation easily passes through materials like plastics and cardboard, they could be particularly useful in manufacturing, quality control and process monitoring. They could also be handy in telecommunications systems and for security screening, because many materials have unique spectral signatures in the terahertz range, he said.

"The discovery opens up new possibilities for waveplates," Baydin said. A waveplate alters the polarization of light that travels through it. In devices like terahertz spectrometers used to analyze the molecular composition of materials, being able to adjust polarization up to a full 90 degrees would allow for data gathering at a much finer resolution.

"We found that specifically at far-infrared wavelengths -- in other words, in the terahertz frequency range -- this anisotropy is nearly perfect," Baydin said. "Basically, there's no attenuation in the perpendicular polarization, and then significant attenuation in the parallel direction.

"We did not look for this," he said. "It was completely a surprise."

He said theoretical analysis showed the effect is entirely due to the nature of the highly aligned nanotube films, which were vanishingly thin but about 2 inches in diameter. The researchers both observed and confirmed this giant polarization rotation with experiments and computer models.

"Usually, people have to use millimeter-thick quartz waveplates in order to rotate terahertz polarization," said Baydin, who joined the Kono lab in late 2019 and found the phenomenon soon after that. "But in our case, the film is just nanometers thick."

"Big and bulky waveplates are fine if you're just using them in a laboratory setting, but for applications, you want a compact device," Kono said. "What Andrey has found makes it possible."

Abu Dhabi, UAE: NYU Abu Dhabi (NYUAD) researchers have developed a special noncontact multi-physics probe (NMP) that enables them to collect cytoplasmic samples from single tumor cells without disrupting their spatial configurations in the original tissue. The tiny tool can also be used to introduce foreign materials to selected cells within the tissue to alter their genetic makeup. As a result, the NMP will facilitate advanced studies that could improve the current understanding of the basic building blocks of diseases, including cancer and Alzheimers, and lead to the development of new therapies. Moreover, this could lead to a powerful tool in the field of stem cell biology and reprogramming.

This new, high-precision technology might also contribute to the world's most ambitious genetic project, the Human Cell Atlas, by enabling sequential, non-invasive and multiplexed genetic manipulation and subcellular "biopsy" sampling with a single tool.

The ability to analyze single-cells while retaining the same spatial configurations as the original tumor is fundamental for understanding cells' diversity and heterogeneity within a tumor. Therefore, developing tools for probing and analyzing single cells while in their natural physiological environment is critical.

In their study, Noncontact Multiphysics Probe for Spatiotemporal Resolved Single?Cell Manipulation and Analyses published in the journal Small, NYUAD Assistant Professor of Mechanical and Biomedical Engineering and Principal Investigator at the Advanced Microfluidics and Microdevices Laboratory Mohammad A. Qasaimeh and his team present the process of developing the new technology. The team built on their previous efforts in 3D printed microfluidics probes and their recent development of the Micro-electro-Fluidic Probe for cell separation and patterning. However, this NMP is significantly miniaturized to achieve single cell manipulation, the design is advanced for subcellular operations, and the device is integrated with electrical components for single cell stimulation.

"This is analogous to collecting blood samples from a patient without physical contact between the needle and the skin -- however, in the case of the NMP, the patient is a single cancer cell, and the 'needle' is five times thinner than a strand of human hair and utilizes electrical signals to puncture through the cell membrane, without physical lancing" said Ayoola T. Brimmo, the first author and a former PhD student with Professor Qasaimeh's group.

The use of advanced 3D printing tools allowed the team to create over 200 prototypes with rapid iterations, and facilitated the inclusion of 3D microelectrodes at the tip of the NMP. The NMP effectively retrieved RNAs from single cancer cells and introduced synthetic DNAs (plasmids) into single cancer cells, all while keeping cells within their tissue-like configuration and leaving other neighbouring cells untouched.

"The NMP we've developed can guide the way for more in-depth genetic analyses of single-cells and a more fundamental understanding of cancer and other complex diseases," said Qasaimeh. "Our future research aims at increasing the throughput of the NMP, as well as increasing the precision for targeting sub cellular components. We expect such developments to enable unparalleled insights on the fundamental internal workings of all lifeforms."

A study led by MedUni Vienna (Institute of Cancer Research and Comprehensive Cancer Center Vienna) sheds light on the mechanisms that lead to extremely aggressive metastasis in a particular type of pancreatic cancer, the basal subtype of ductal adenocarcinoma. The results contribute to a better understanding of the disease. The study has recently been published in the leading journal "Gut".

The most prevalent form of pancreatic cancer, Pancreatic Ductal AdenoCarcinoma (PDAC) is usually divided into two subtypes, a classical subtype and a basal subtype. The latter is highly aggressive and tends towards early metastasis. One of the distinguishing features between the two subtypes is that the classical subtype exhibits the protein GATA6. This is no longer present in the basal subtype, while the protein DeltaNp63 can be detected in this type.

The study team led by Paola Martinelli, who, at the time of the study, was research group leader at the Institute of Cancer Research and member of the Comprehensive Cancer Center of MedUni Vienna and Vienna General Hospital, found that the switch-over of the cancer cells from the classical to the basal type occurs in two stages: first of all, GATA6 is lost but this is not yet sufficient for the expression of DeltaNp63. Only after the concomitant loss of two additional proteins, transcription factors HNF1A and HNF4A, does DeltaNp63 emerge and the tumour switch to the aggressive form. Martinelli comments: "This suggests that reinstating the classical subtype could serve to reduce metastasis. Moreover, the tumour would once again be easier for the immune system to detect, since GATA6 not only hinders the ability of tumours to adapt to their surroundings but also blocks the mechanisms that hide tumours from the immune system."

The last ice age ended almost 12 000 years ago in Norway. The land rebounded slowly as the weight of the ice disappeared and the land uplift caused many bays to become narrower and form lakes.

Fish became trapped in these lakes.

Sticklebacks managed to adapt when saltwater became freshwater, and they can still be found in today's coastal lakes along the Norwegian coast.

Saltwater gradually changed to brackish water and later to freshwater. This environmental change naturally led to a total replacement of the animal and plant life.

The exception is the tiny stickleback, which successfully adapted as saltwater became freshwater and can still be found in today's coastal lakes along the Norwegian coast. How in the world did this little fish manage to adapt to such big changes, even in several places at the same time?

The 12 000-year-old bones of three-spine stickleback can give us some answers.

The three-spine stickleback is found in freshwater lakes, in saltwater marine environments and in brackish water, a mixture of the two. Although the fish belong to the same species, they look a little different depending on where they are found.

Since so many lakes were cut off from the sea, we know that sticklebacks adapted to the environmental changes in multiple places simultaneously. Yet the changes happened independently of each other, without any interbreeding, which pointed to a genetic reason behind the phenomenon.

Three-spine sticklebacks are therefore well suited for the study of what biologists call "parallel evolution" - evolutionary changes that occur in parallel but independently of one another.

"Usually we only have access to present-day sticklebacks. We compare groups from freshwater and marine habitats and assume that fish from the sea today are genetically comparable to the marine fish that adapted to freshwater in earlier times," says Andrew Foote, an associate professor from the Norwegian University of Science and Technology's (NTNU) University Museum and Bangor University in Wales.

Through some interdisciplinary collaboration, researchers gained access to 12 000-year-old bones from two sticklebacks in today's Hammerfest municipality.

These ancient artefacts can certainly provide a useful basis for study. But sticklebacks that live in marine environments today have also evolved since those times, so they might not be quite the same as the ones that adapted to freshwater at the end of the ice age. This makes studying them tricky for biologists.

"Although these bones belong to fish that died over ten thousand years ago, when most of Scandinavia was covered by ice, they contain fragments of DNA that we can study. The genes give us insight into the early stages of the transition from saltwater to freshwater," says Foote.

The results of the international cooperative effort were recently presented in the journal Current Biology. Experts in geology, ancient DNA and genetic evolution collaborated to compare present-day and ancient threespine sticklebacks.

Foote teamed up with professor and geneticist Tom Gilbert from the University of Copenhagen. They had access to a state-of-the-art laboratory for the study of ancient DNA and used newly developed methods to sequence the genomes of the 12 000-year-old sticklebacks.

"Research on threespine sticklebacks over the last 20 years has provided key insights into the genetic basis of parallel adaptation. We've found that adaptation can proceed via newly arising mutations, but often involves reusing an already existing genetic variation that spreads among populations," says Dr. Felicity Jones at the Max Planck Society's Friedrich Miescher Laboratory in Tübingen, Germany.

Populations are groups of animals of the same species that are geographically more or less separated from other groups of the same species.

"It's really striking that we could detect variants known to be adaptive to freshwater in one single marine colonizer by overcoming all the challenges related to sequencing ancient DNA. This conclusively demonstrates that freshwater-adaptive genetic variants were present in the stickleback populations that colonized freshwater lakes from the sea thousands of years ago," says doctoral student and lead author Melanie Kirch, who is also from the Friedrich Miescher laboratory.

This proves that gene variants that enable sticklebacks to live in freshwater already existed in stickleback populations in the ocean several thousand years ago. These marine fish could thus colonize the freshwater lakes that arose.

But Kirch also points out that the results show that parallel evolution has some limitations. "Even when the colonizing ancestor carried genetic variants known to be adaptive in freshwater, these variants aren't always present in the contemporary population. This tells us that even beneficial freshwater-adaptive variants can be lost during the evolutionary process of adaptation, likely by random chance - a process known as 'genetic drift,'" she says.

This ancient DNA has provided a window into the past and has enabled researchers to study the genetic makeup of the ancestors of today's fish. Researchers can thus track adaptations that have taken place over several thousand years that also help them understand more of the evolutionary process.

In this way, they can create better models and gain new insight into factors that affect the direction, speed and molecular basis behind evolution in nature.

The sticklebacks were found by Norwegian geologists who actually studied the land uplift that has taken place along the Norwegian coastline since the ice retreated from Scandinavia.

Geologists stumbled across the fish bones in several sediment samples taken from lakes along the coast. Sediments are materials that sink to the lake bottom over the years and are deposited in layers according to age, unless someone or something disturbs the order of the layers. In the more-or-less untouched lakes studied, the sediment layers show traces of the transition from a marine environment to a freshwater environment.

The fish bones washed out of the sediment samples were amazingly well preserved.

Carbon dating can help geologists reconstruct how sea levels have changed over time, but this time the technique was also useful in another way.

"The fish bones we washed out of the sediment samples were amazingly well preserved. We could immediately identify them as originating from threespine sticklebacks," says researcher Anders Romundset at the Norwegian Geological Survey.

They determined the age by carbon dating plant material that was found in the same layers as the bones. The analysis also showed that these particular fish had lived in brackish water, which indicates that the lake was close to becoming disconnected from the sea.

Since the bones were found in a transition period between marine and freshwater habitat, the genes showed both genetic variations associated with an adaptation to the sea, as well as some genes that clearly showed an adaptation to freshwater.

A reason for these findings could be due to the fact that Parkinson's patients often also have many risk factors for a severe course of Covid-19. For the first time, the cross-sectional study provides detailed nationwide data. The research team led by Professor Lars Tönges reports in the journal Movement Disorders of 4 May 2021.

Nationwide analysis of hospital data

The team headed by Lars Tönges has analysed data on Parkinson's treatment in 1,468 hospitals. The data were taken from nationwide databases in which information on the treated diseases and of treatments carried out in hospitals is publicly collected, for example by the Institute for the Hospital Remuneration System or the Federal Statistical Office.

A comparison between the period of the first wave from 16 January to 15 May 2020 with the same period of the previous year showed that overall hospital treatments due to Parkinson's disease had decreased by almost one third during the first wave. At the peak of the wave, the number of cases even fell by a good 70 per cent. The reason for this was, on the one hand, the patients' concern about contracting the SARS-CoV-2 virus in hospital. On the other hand, many non-emergency treatments were postponed to ensure intensive care capacity.

Frailty increases the risk

The analysis also showed that Covid-19 was more common in hospitalised patients with Parkinson's disease than in patients without Parkinson's disease, especially in those of advanced age over 65 years or with particularly severe Parkinson's disease. It was also confirmed that Parkinson's patients who had Covid-19 were more likely to be affected by the known high-risk conditions. "Parkinson's patients may be at particular risk for severe Covid-19 due to frailty, which increases with age and advanced disease stages," explains Lars Tönges. "Lung function may be impaired by common comorbidities and respiratory muscle weakness associated with Parkinson's. In addition, dysphagia makes people more susceptible to pneumonia."

More deaths than in the previous year

In the nationwide cross-sectional study conducted by the neurologists in Bochum, the hospital mortality of Covid-19 patients with Parkinson's disease was higher than that of Covid-19 patients without Parkinson's disease, especially in those between 75 and 79 years of age. The Parkinson's patients who died with Covid-19 were more likely to have chronic kidney disease and were more likely in a later stage of the disease compared to survivors. "Remarkably, more Parkinson's patients died in hospitals in 2020 than in 2019, which may also be due to circumstances associated with overall Covid-19 disease management," concludes Tönges.

"The study illustrates the need to ensure optimal treatment of Parkinson's patients despite the current pandemic," stress the authors. Telemedical services, for example, can also support this in the future. Data on the developments during the second and third waves are expected soon.

Parkinson's disease

Parkinson's disease is one of the most common neurological disorders. It reduces mobility, fine motor skills, balance and the ability to walk. Depression, sleep disorders and memory problems can also be associated with the disease. It mainly affects people in the second half of life and is more common in men. Several people affected by Parkinson's have concomitant diseases such as coronary heart disease, high blood pressure or kidney disease. "Since precisely these are significant risk factors for a severe course of Covid-19, the question arose whether inpatients with Parkinson's also develop a severe course of Covid-19 more frequently or die from it," explains lead author Dr. Raphael Scherbaum from the RUB hospital.

At the same time, the Covid-19 pandemic also affects the healthcare of all Parkinson's sufferers. "Rising numbers of patients show how important hospitalisation is, especially during illness crises, for example after a fall or when medication is not effective enough," says Scherbaum. How much the first wave of the pandemic reduced the care of patients with Parkinson's was not known until now.

Corona research at RUB

RUB has been conducting research on Covid-19 since the beginning of the coronavirus pandemic - across all disciplines. This means that not only medicine and life sciences are involved, but also, for example, psychology, sociology, law, education and history. An overview of the research projects can be found online.

No one expected the "Automated Guided Vehicles" at St. Olavs Hospital in Trondheim, Norway, to have personalities. These motorized units, like long boxes on wheels, are merely meant to transport garbage, medical equipment or food from one part of the hospital to another.  But because they have to interact with humans, by warning them to get out of the way, they have to talk.

And that's when the fun began.

Instead of using a generic Norwegian voice, they decided to give the hospital robots a voice that used the strong, distinctive local dialect. Suddenly these stainless-steel boxes, rolling around the hospital to transport goods, had a personality.

They were kind of pushy. A little rude, really. But fun.

Children with illnesses who were being treated in the wards began to play games with them, trying to find and identify them. One parent with a gravely ill child found solace in the robots' endless, somewhat mindless battles as they unsuccessfully ordered inanimate objects--like walls--to get out of the way.

In a new study, researchers from the Norwegian University of Science and Technology (NTNU) examine just how the robots came to be seen as friendly, animal like creatures -- and why that matters.

"We found that these robots, which were not created to be social robots, were actually given social qualities by the humans relating to them," said Roger A. Søraa, a researcher at NTNU's Department of Interdisciplinary Studies of Culture and Department of Neuromedicine and Movement Science, and first author of the new study. "We tend to anthropomorphize technologies like robots--giving them humanlike personalities--so we can put them into a context that we're more comfortable with."

Health care, especially in hospitals, involves lots of specialized skills and expertise. Whether it's nurses administering to patients around the clock, or doctors providing critical surgery or other highly specialized care, there's plenty of work for people to do in a hospital setting.

So why not leave some of the more mundane work -- say, moving food from the cafeteria to different hospital units, or bringing clean linens to nursing stations -- to an automated industrial robot?

"These are types of jobs that can often be dull, dirty or dangerous, or what we call 3-D jobs," Søraa said. "These are jobs that humans don't necessarily want to do or like to do. And those are the jobs we are seeing becoming robotized or digitalized the fastest."

That's exactly what St. Olavs Hospital decided in 2006, when they brought 21 AGVs, made by Swisslog Healthcare, into the hospital to do some very basic lifting and moving work. St. Olavs was the first hospital in Scandinavia to adopt this technology.

Since then, the robots have been driving around the hospital's halls, following pre-defined routes among different pick-up and delivery points, using lasers to navigate. They also have sensors that enable them to avoid people, obstacles and dangerous situations. They even take elevators -- much to the annoyance of hospital staff -- but more about this later.

And because they share the same areas as humans, they can say a few sentences when needed.

That, it turns out, is one of the key things that helps transform a metallic industrial box on wheels into a friendly animal-like creature with a personality.

Marianne Fostervold, then at NTNU's Department of Architecture and Planning, and her colleagues didn't actually set out to study the hospital's robots. Instead, they were interested in how people adjusted to, used, got around and were affected by the hospital's architecture, which has been changed and modernized over the last decade.

The study was done in the hospital's Women and Children's Centre, which includes birthing facilities and a children's cancer department, making it a place where people often have strong, sometimes life-altering feelings and experiences.

The researchers followed health care staff, patients and visitors on their routes in the hospital, and asked them questions about why they moved the way that they did, where they were headed, and how they felt at the time. The interviews were "open", meaning that they were able to explore the questions asked, based on the responses of the interviewees.

Much to the researchers' surprise, the AGVs kept turning up as a part of the conversation.

"There are quite a lot of different stakeholders relating to these robots -- patients, caregivers, nurses, doctors, cleaners. There's a whole bunch of people that have to navigate a world now where robots also are living and working," Fostervold said.

So what did these people think?

One distraught father who walked the hospital hallways after hearing of his child's terminal cancer diagnosis told researchers about when he encountered a AGV that was stuck between some trolleys.

The robot kept moving back and forth, fruitlessly repeating its self-important message in the local dialect: "I am a hospital robot! You need to move!"

This slapstick ballet, of an inanimate object stubbornly trying to persuade equally inanimate objects to get out of its way, made the father smile.  He told the researchers it was a bright moment in an otherwise dark time.

"These service robots were not created to be social robots," Søraa said, since they are just moving things around. "And yet people still tend to socialize with them and find social qualities in them."

That matters, Søraa said, because it helps people accept the robots, and through that acceptance, other technologies that are coming our way are not seen as too alien. With robots like these, the goal is to make life easier and improve quality of care, because they can do things like free up resources at the hospital that would otherwise be required to do the jobs the AGVs do now.

"I see robots as emissaries of technologies. They give us a very good insight into how to understand quite cutting-edge technology in our societies," he said. "And we are now living in a society that is more and more getting used to the fact that robots are now doing more work, like cleaning and transporting goods."

One of the key things the AGVs have to do is move goods from one floor to another. Naturally, they have to ride hospital elevators to do their job -- much to the annoyance of some of the nursing staff, who have to compete with the robots to use the elevators.

The robots were initially made to override all other users and commandeer an elevator so they can get their work done.

One nurse told the researchers of problems she had with the AGVs preventing her from using the elevators when she was trying to transport patients in recovery.

"I was told by a robot that I had to leave the elevator because the robot was using it. It overrides the elevator, and I was let out into the basement of the hospital with a patient from recovery and had to get out of there. So, we stood there, and had to wait until the robot had finished," she said.

Søraa says this is an example that robot designers should think about as they work to make machines that can more easily integrate into existing social situations. Taking over an elevator doesn't seem like that big a problem, but the AGVs should not be able to take over elevators when sick patients need them.

The interaction between the AGVs and the elevators also helps anthropomorphize the AGVs, Søraa said.

The elevators also "speak", as a way to help people who are visually impaired.  They announce when the doors are opening and closing, and also state which floor the elevator is on. When an AGV is in the elevator, the elevator politely asks humans to "please use another elevator, this one is reserved."

But the elevator voices are female and speak a very polite, standard dialect.  The contrast between the polite elevators and the burly, rude AGVs and their local dialect is part of what makes the AGVs funny, and more easily accepted, Søraa said.

"When telling people to move out of the way, the robot will shout "Pass dæ, robottralle på vei. Æ skifte retning!" which translates as "Move away, robot trolley coming through. I'm changing direction!"

"We found that the use of the local dialect really gave the robots more of a personality," he said. "And people often like to give non-living things human qualities to fit them within existing social frameworks."

The coronavirus pandemic has created a great demand for rapidly diagnosing SARS-CoV-2 infections. Reliable rapid tests are needed, for example, at airports and ports for testing travellers quickly and effortlessly before their journey.

Researchers at the University of Helsinki have developed a new rapid assay principle for viral antigen detection, applying it to diagnosing SARS-CoV-2 infections.

The test is based on a phenomenon known as time-resolved Förster resonance energy transfer (TR-FRET), where energy travels between two light-sensitive molecules when they are close enough to each other. TR-FRET makes it possible to measure viral particles or the body's own proteins by using what are known as 'mix and read'-type tests on complex biological samples, such as serum or even whole blood. In fact, the researchers have previously applied the procedure in the rapid detection of antibodies.

In practice, the TR-FRET solution of the new SARS-CoV-2 rapid test functions like this: a nasopharyngeal swab taken from the test subject is mixed in a test solution which contains antibodies that recognise the SARS-CoV-2 nucleoprotein or spike protein. The antibodies marked with fluorescent labels bind with SARS-CoV-2 particles, forming molecular assemblies, or complexes, whose existence can be confirmed/detected by using a TR-FRET assay. The results come in roughly 10 minutes later: the formation of any complexes demonstrates, to a high degree of certainty, an infection caused by SARS-CoV-2 in the test subject.

A research article proving the viability of the rapid test was published this week in the mBio journal.

"We demonstrated in our study that a technique based on the TR-FRET phenomenon can be used to diagnose SARS-CoV-2 infections in clinical specimens", says Jussi Hepojoki, docent of virology and Academy of Finland research fellow at the University of Helsinki.

The antigen test detected almost all specimens containing the virus

In the research article, the researchers investigated the functioning of the rapid test using 48 specimens which had been selected on the basis of a positive SARS-CoV2 PCR test, with varying concentrations of viral RNA.

"We demonstrated that the technique we have developed was able to detect almost all positive specimens (37/38), from which we were able to isolate SARS-CoV-2 in cell culture. In other words, the carriers were likely to continue to spread the virus at the time of sample collection," Hepojoki says.

In contrast, 10 of the selected group of positive SARS-CoV-2 samples produced a positive result in a PCR test even though virus isolation was no longer possible. None of these samples yielded a positive antigen test result.

According to Hepojoki, the PCR tests available are sensitive enough to detect coronavirus even when the sample collection has not been optimal. At the same time, this sensitivity can result in cases of positive PCR test results when the infection itself has been eliminated.

"Residues of RNA, the virus's genetic material, can remain in the human body. Even a single piece of viral RNA can yield a positive result in PCR tests, whereas antigen-based tests appear to better correlate to whether SARS-CoV-2 can be isolated from the specimen, or whether the person is transmitting the virus at the time of sample collection," Hepojoki describes.

A safe way for testers to detect potential coronavirus infections

Hepojoki says that another benefit of the new rapid test developed by the researchers is its safety for testers: in practice, the virus becomes inactivated soon after being mixed in the test solution.

He says that rapid antigen-based tests could be particularly useful for testing not only travellers, but also people at educational institutions. A TR-FRET reader roughly the size of a desktop computer is needed for the test, making it possible, at least in theory, to carry out testing almost anywhere.

"The theoretical capacity of the test is very high. According to our calculations, it would be possible to manually analyse as many as 500 samples per hour, with one person doing the testing and using a single testing device. Also, the cost of test reagents is fairly low," Hepojoki notes.

In addition to the novel coronavirus, the assay principle can be utilised to detect other respiratory infections or basically any molecule: the only thing needed is an antibody capable of identifying the target molecule.

Scientists from Tomsk Polytechnic University and Université Grenoble Alpes (France) have proposed a more accurate method for loading capability assessment of power transformers. As an example, the scientists defined the loading capability of the power transformer in Tomsk and Grenoble. The research findings are published in the International Journal of Electrical Power and Energy Systems (IF: 3,588, Q1).

The cost of a power transformer can reach a few hundred million rubles that makes it the most expensive element of an electrical grid. Therefore, power engineers tend to use the loading capability of transformers in full. The method proposed by the TPU scientists can help to operate power transformers closer to their thermal limit. It will allow operators to control power systems of higher transfer capability, grid electricity suppliers to postpone investment to change power transformers, end-users to use cheaper electrical energy.

"Nominal rating of most kinds of power transformers is designed for an ambient air temperature of 20°C. Nevertheless, the ambient air temperature is inconstant and changes during a day, month, year. Due to the temperature changes, the actual admissible loading of a transformer can be either higher or lower than its nominal rating.

In both cases, the admissible loading has to meet four limitations: current of a transformer, the hot-spot temperature of a winding, a top-oil temperature and thermal wear of insulation. The existing methods of the admissible loading assessment do not take into consideration all of these limitations simultaneously, as well as admissible short-term overloading of transformers in normal operating conditions," Ildar Daminov, a postgraduate of TPU and Université Grenoble Alpes, a co-author of the article, explains.

The TPU researchers proposed a feasible region method. Due to this method, using the full-scale current, the winding and oil temperatures, it is possible to calculate the entire region of admissible loadings. Moreover, besides the characteristics, it is enough to know only the air temperature to calculate the region of admissible loadings. It allows defining admissible long-term loadings and admissible short-term overloadings of transformers taking into account practically all possible load profiles.

As a calculation example, the scientists defined the loading capability of an ONAF transformer based on the analysis results of the ambient air temperature in Tomsk and Grenoble during the last 35 years. The results showed that depending on the air temperature, the loading limit of the researched transformer can surpass its nominal rating on average from 15% to 45% in Tomsk and from 5% to 41% in Grenoble. Furthermore, the loading capability of the transformer in Tomsk can surpass the nominal rating for 88,5% of the time (even without taking into account admissible short-term overloading), as cold Siberian climate allows effectively withdraw heat from power transformers. This indicator is lower and equal to 79% in Grenoble.

"The power transformer researched by us is designed based on International Standard IEC 60076-7. It operates using rather universal thermal characteristics, which in general meet a variety of transformers. Hence, the research findings can be applied to transformers of alternative design," Anton Prokhorov, Associate Professor of the TPU Division for Power and Electrical Engineering, a co-author of the article, says.

As a result, the scientists listed recommendations on transformer overloading. Thus, it is admissible to increase loading to 120°C during 26 days per year or to 140°C during two weeks for a transformer with a winding temperature of 98°C in normal operating conditions. Transformers with a standard temperature of 110°C can be overloaded to 120°C during 98 days per year or to 140°C during 20 days per year.

Due to the extensive clearing of their habitat, these primates sometimes turn to palm oil monocultures while foraging. This often leads to conflicts with farmers. The macaques do not damage the palm oil fruits to any great extent. On the contrary, they can even benefit palm oil cultivation, as they are excellent hunters of the masses of rats found on plantations, the main pest found there. As a new study has now been able to prove, however, regularly visiting the plantations has a significant impact on macaques' social behaviour. This was shown by researchers from the Max Planck Institute for Evolutionary Anthropology (MPI-EVA), Leipzig University (UL), Universiti Sains Malaysia (USM) and the German Centre for Integrative Biodiversity Research (iDiv). The new findings may help to develop appropriate measures for protecting the primate species, which is listed as vulnerable by the IUCN, and to promote peaceful coexistence between humans and wild animals.

It is well known that human-induced disturbances can affect the behaviour of various wildlife species, including primates. Previous studies have mainly focused on changes in the activity patterns or feeding behaviour of animals living in urban or tourist areas and fed by humans. "We, on the other hand, wanted to look at how different habitats, including anthropogenically highly modified habitats such as palm oil plantations, affect social behaviour in macaques," said Anna Holzner, first author of the study, which was recently published in Scientific Reports. "For most primate species social interactions within the group are particularly essential for successfully surviving in large, complex social groups in their natural habitat."

Two groups of southern pig-tailed macaques observed over a period of months

To find out, the scientists spent several months observing 50 individuals of two social groups of southern pig-tailed macaques (Macaca nemestrina) in Segari (Malaysia). Dr Nadine Ruppert (USM), head of the local research station, stressed: "This is the first population of this shy species to be habituated to scientific observers. Every day, the groups walk for about three hours from the rainforest to the neighbouring plantation." The researchers were interested in the differences in the animals' social behaviour between the rainforest - whose dense vegetation provides protection for the macaques - and two habitats within the palm oil plantation, the interior of the plantation and its edge. These both have an abundance of food in the form of palm oil fruits and rats, and also an increased potential for conflict with humans, but only the plantation edge provides cover in the form of a safe avenue of retreat into the adjacent forest. The study focused on aggressive interactions, relationship-promoting behaviours such as grooming and juvenile social play, social networking within the group, and mother-infant relationships.

As expected, the macaques use the plantation mainly as an additional food source. Both inside the plantation and at its edge, they spent about two-thirds of the time foraging and eating. Aggressive behaviour in the macaques was significantly increased in the plantation interior compared to the other habitats - a well-known phenomenon, especially in connection with foraging. However, this was not only triggered by the monkeys' increased feeding activity in the plantation, but rather the plantation itself played a major role: according to the scientists, the interior of the plantation, unlike the rainforest and the edge of the plantation, offers little protection from potential attackers and puts the animals under stress, which may in turn trigger the increased rates of aggression.

Macaques strongly reduced bonding behaviour

Furthermore, the researchers expected strong impairments in the macaques' positive social interactions. "In particular, bonding social interactions were observed to be greatly reduced in the plantation interior," said Holzner. "Even during periods not used for feeding, the monkeys there showed almost no mutual grooming or play behaviour." Unlike the forest, the area inside the plantation poses greater safety risks for the monkeys. The likelihood of encountering potential predators, especially humans or stray dogs, in the plantation was significantly increased compared to the forest. In order to be more vigilant against these threats, it may therefore be the case that macaques compromise on their social behaviour and move time-consuming social interactions into the forest, which offers greater protection. The importance of the rainforest as a safe retreat was illustrated by the results at the edge of the plantation. Protected by the nearby forest, the macaques not only displayed social interaction, but in some cases even increased it. "What surprised us was that the frequency of mutual grooming was almost three times higher at the plantation edge than in the forest," said Professor Anja Widdig (UL/MPI-EVA/iDiv), lead author of the paper. "Other studies have shown that grooming can serve to reduce stress," said Widdig. "We suspect that this was at least one of the reasons for the increased investment in social interactions at the plantation edge. Especially before or shortly after visiting the stressful, competitive plantation environment, stress reduction would be of great importance for the animals. Also lower-ranking animals in particular could secure tolerance from their conspecifics in this way, and thus access to a share of the energy-rich food." This is also indicated by changes in the groups' network structures: "In contrast to the forest, it was not the higher-ranking animals that had the best social networks on the plantation, but subordinate individuals," said Widdig.

As expected by the researchers, the plantation also had an effect on the smallest social units within the group: mother-infant pairs. Both inside and at the edge of the plantation, mothers maintained more body contact with their offspring. This could have a number of implications for offspring development. Holzner points out: "If offspring development is delayed, then mothers would have to invest more time and energy, which in turn could extend inter-birth intervals. It is precisely the survival of species whose populations are already threatened that could be jeopardised in the long term as a result."

Protecting the habitat of the vulnerable pig-tailed macaque

"The study demonstrates that human-induced habitat changes can severely alter social behaviour in groups and, furthermore, disrupt mother-infant relationships - even in the absence of regular direct contact with humans," said Widdig. It is essential to protect the remaining populations of southern pig-tailed macaques and their habitat and facilitate their coexistent with humans in anthropogenic landscapes. "Their protection will ultimately contribute to maintaining biodiversity and important ecosystem functions of tropical habitats," said Ruppert. "Maintaining forest corridors is an important conservation tool to create viable interfaces between forests and agricultural landscapes. These can not only facilitate natural dispersal and link fragmented wildlife populations affected, but also enable animals to engage in essential social interactions that are essential for the long-term survival of primates and other species."

Active music-making can provide cognitive benefits to older adults with mild cognitive impairment or dementia, according to an analysis of all relevant studies. The analysis, which is published in the Journal of the American Geriatrics Society, also found that music may help improve their quality of life and mood.

The analysis included nine studies with a total of 495 participants. The authors noted that music-based interventions could potentially provide millions of older adults with critical support for their cognitive, emotional, and social well-being.

"We are excited to see these results because participating in music, like singing in a choir or playing in a drum circle, is a safe, engaging activity that our research demonstrates can support cognition at a critical time for older adults facing cognitive decline," said lead author Jennie L. Dorris, MM, of the University of Pittsburgh.

Little is known concerning environmental contaminants in predators at the top of a food chain. A study published in Environmental Toxicology and Chemistry has demonstrated that new types of brominated flame retardants accumulate in the tissues of killer whales near Norway and are also passed on to nursing offspring.

Investigators also detected man-made chemicals called perfluoroalkyl substances (PFAS) in the tissues of adult killer whales. Thresholds for health effects of PFAS in marine mammals are not established, but the chemical has been linked to reproductive and endocrine effects in wildlife. In addition, polychlorinated biphenyls (PCBs), which have long been banned, were detected in the blubber of 7 of the 8 killer whales in the study at levels that exceeded the proposed threshold for toxicological effects in marine mammals.

"Levels of pollutants in top predators give not only an indication of ecosystem health, but of the persistence of chemicals, passive mobility in the environment, and active biotransport with migrating animals," the authors wrote. "Our results are relevant for the continued environmental monitoring of contaminants in the Arctic."