Unsettling currents: Warm water flowing beneath the ‘Doomsday Glacier’

For the first time, researchers have been able to obtain data from underneath Thwaites Glacier, also known as the “Doomsday Glacier.” They find that the supply of warm water to the glacier is larger than previously thought, triggering concerns of faster melting and accelerating ice flow.

With the help of the uncrewed submarine Ran that made its way under Thwaites glacier front, the researchers have made a number of new discoveries. Professor Karen Heywood of the University of East Anglia commented:

“This was Ran’s first venture to polar regions and her exploration of the waters under the ice shelf was much more successful than we had dared to hope. We plan to build on these exciting findings with further missions under the ice next year.”

The submersible has, among other things, measured the strength, temperature, salinity and oxygen content of the ocean currents that go under the glacier.

Global sea level is affected by how much ice there is on land, and the biggest uncertainty in the forecasts is the future evolution of the West Antarctic Ice Sheet, says Anna Wåhlin, professor of oceanography at the University of Gothenburg and lead author of the new study now published in Science Advances.

Impacts global sea level

The ice sheet in West Antarctica accounts for about ten percent of the current rate of sea level rise; but also the ice in West Antarctica holds the most potential for increasing that rate because the fastest changes worldwide are taking place in the Thwaites Glacier. Due to its location and shape, Thwaites is particularly sensitive to warm and salty ocean currents that are finding their way underneath it.

This process can lead to an accelerated melting taking place at the bottom of the glacier and inland movement of the so-called grounding zone, the area where the ice transitions from resting on the seabed to floating in the ocean.

Due to its inaccessible location, far from research stations, in an area that is usually blocked by thick sea ice and many icebergs, there has been a great shortage of in situ measurements from this area. This means that there are big knowledge gaps for the ice-ocean boundary processes in this region.

First measurements performed

In the study, the researchers present the results from the submersible that measured strength, temperature, salinity and oxygen content of the ocean currents that go under the glacier.

“These were the first measurements ever performed beneath Thwaites glacier,” says Anna Wåhlin.

The results have been used to map the ocean currents underneath the floating part of the glacier. The researchers discovered that there is a deep connection to the east through which deep water flows from Pine Island Bay, a connection that was previously thought to be blocked by an underwater ridge.

The research group has also measured the heat transport in one of the three channels that lead warm water towards Thwaites Glacier from the north. “The channels for warm water to access and attack Thwaites weren’t known to us before the research. Using sonars on the ship, nested with very high-resolution ocean mapping from Ran, we were able to find that there are distinct paths that water takes in and out of the ice shelf cavity, influenced by the geometry of the ocean floor” says Dr Alastair Graham, University of Southern Florida.

The value measured there, 0.8 TW, corresponds to a net melting of 75 km3 of ice per year, which is almost as large as the total basal melt in the entire ice shelf. Although the amount of ice that melts as a result of the hot water is not much compared to other global freshwater sources, the heat transport has a large effect locally and may indicate that the glacier is not stable over time.

Not sustainable over time

The researchers also noted that large amounts of meltwater flowed north away from the front of the glacier.

Variations in salinity, temperature and oxygen content indicate that the area under the glacier is a previously unknown active area where different water masses meet and mix with each other, which is important for understanding the melting processes at the base of the ice.

The observations show warm water approaching from all sides on pinning points, critical locations where the ice is connected to the seabed and give stability to the ice shelf. Melting around these pinning points may lead to instability and retreat of the ice shelf and, subsequently, the upstream glacier flowing off the land. Dr Rob Larter of the British Antarctic Survey commented:

“This work highlights that how and where warm water impacts Thwaites Glacier is influenced by the shape of the sea floor and the ice-shelf base as well as the properties of the water itself. The successful integration of new sea-floor survey data and observations of water properties from the Ran missions shows the benefits of the multidisciplinary ethos within the International Thwaites Glacier Collaboration.”

“The good news is that we are now, for the first time, collecting data that is necessary to model the dynamics of Thwaite’s glacier. This data will help us better calculate ice melting in the future. With the help of new technology, we can improve the models and reduce the great uncertainty that now prevails around global sea level variations.” says Anna Wåhlin.

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Brain disease transmitted by tick bites may be treatable

Tick-borne encephalitis is a disease just as nasty as it sounds. Once bitten by an infected tick, some people develop flu-like symptoms that resolve quietly but leave behind rampant neurological disease — brain swelling, memory loss, and cognitive decline. Cases are on the rise in Central Europe and Russia with some 10,000 incidents reported each year. Vaccines can provide protection, but only for a limited time. There is no cure.

Now a new study describes antibodies capable of neutralizing the virus transmitted by tick bites. These so-called broadly neutralizing antibodies have shown promise in preventing TBE in mice and could inform the development of better vaccines for humans. Further, preliminary results suggest that the antibodies may not only prevent tick-borne encephalitis but even treat the condition, as well as the related Powassan virus emerging in the United States.

Lead author Marianna Agudelo and colleagues in the laboratory of Rockefeller’s Michel C. Nussenzweig examined nearly 800 antibodies obtained from individuals who had recovered from TBE or had been vaccinated to prevent infection. The most potent antibodies, designated VH3-48, turned out to be best suited to fend off future infections. They found that VH3-48 neutralized lab-grown varieties of the TBE virus, as well other tick-borne illnesses including the Langat, Louping ill, Omsk hemorrhagic fever, Kyasanur forest disease, and Powassan viruses.

The researchers also showed that these powerful antibodies are not common; in fact, most of the antibodies produced by humans exposed to TBE virus are of inferior quality, with the coveted VH3-48 antibodies making only occasional appearances. Moreover, vaccinated patients in the study did not manage to develop any VH3-48 antibodies at all. “You’d expect the most prevalent antibodies to be the absolute best, but that is not what we found in TBE,” Agudelo says. “This may explain how the virus tricks the immune system, misdirecting it into producing inferior antibodies.”

The discovery of VH3-48 provides hope for a more effective TBE vaccine. Current vaccines require three doses spaced over two years and only provide about five years of protection before a booster shot is required. Next-generation vaccines built around coaxing the body into producing the rare VH3-48 antibody could be more potent, require fewer booster shots, and also prove protective against a number of tick-borne viruses.

“A vaccine like this would not just be more elegant, but also better focused,” says Michel C. Nussenzweig, the Zanvil A. Cohn and Ralph M. Steinman Professor and head of the Laboratory of Molecular Immunology at Rockefeller. “Now that we have the structures of these antibodies, we know what to target in order to design more effective vaccines.”

Broadly neutralizing antibodies may also provide the first specific treatment for TBE. Nussenzweig, Agudelo, and colleagues found that mice infected with TBE recover after receiving antibody therapy, although it remains to be seen if this finding will translate to humans.

“The next step is a clinical trial with the antibodies,” Nussenzweig says, “perhaps in Europe where there are many cases, to see whether we can ameliorate the symptoms of those suffering from encephalitis.”

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Aluminum is intricately associated with the neuropathology of familial Alzheimer’s disease

A new study published in the Journal of Alzheimer’s Disease Reports continues to support a growing body of evidence that aluminum contributes to the pathogenesis of Alzheimer’s disease (AD). Researchers found aluminum co-located with phosphorylated tau protein, which is an early initiator of AD. This study builds upon two earlier published studies (including Mold et al., 2020, Journal of Alzheimer’s Disease) from the same group.

The new data demonstrate that aluminum is co-located with phosphorylated tau protein, present as tangles within neurons in the brains of early-onset or familial Alzheimer’s disease. “The presence of these tangles is associated with neuronal cell death, and observations of aluminum in these tangles may highlight a role for aluminum in their formation,” explained lead investigator Matthew John Mold, PhD, Birchall Centre, Lennard-Jones Laboratories, Keele University, Staffordshire, UK.

The earlier research highlighted widespread co-localization of aluminum and amyloid-β in brain tissue in familial AD. The researchers used a highly-selective method of immunolabelling in the current study, combined with aluminum-specific fluorescence microscopy. Phosphorylated tau in tangles co-located with aluminum in the brain tissue of the same cohort of Colombian donors with familial AD were identified. “It is of interest and perhaps significance with respect to aluminum’s role in AD that its unequivocal association with tau is not as easily recognizable as with amyloid-β. There are many more aggregates of aluminum with amyloid-β than with tau in these tissues and the latter are predominantly intracellular,” remarked co-author, Professor Christopher Exley.

George Perry, PhD, Editor-in-Chief of the Journal of Alzheimer’s Disease, comments: “Aluminum accumulation has been associated with Alzheimer’s disease for nearly half a century, but it is the meticulously specific studies of Drs. Mold and Exley that are defining the exact molecular interaction of aluminum and other multivalent metals that may be critical to formation of the pathology of Alzheimer’s disease.”

“The new data may suggest that the association of aluminum with extracellular senile plaques precedes that with intracellular aggregates of tau. These relationships with both amyloid-β and tau may account for the high levels of aluminum observed in the brain tissue of donors with familial AD versus those without a diagnosis of neurodegenerative disease,” said Dr. Mold. “Tau and amyloid-beta are known to act in synergy to produce neurotoxicity in AD and our data provide new evidence for a role of aluminum in this process.”

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Stress from work and social interactions put women at higher coronary heart disease risk

Psychosocial stress — typically resulting from difficulty coping with challenging environments — may work synergistically to put women at significantly higher risk of developing coronary heart disease, according to a study by researchers at Drexel University’s Dornsife School of Public Health, recently published in the Journal of the American Heart Association.

The study specifically suggests that the effects of job strain and social strain — the negative aspect of social relationships — on women is a powerful one-two punch. Together they are associated with a 21% higher risk of developing coronary heart disease. Job strain occurs when a woman has inadequate power in the workplace to respond to the job’s demands and expectations.

The study also found that high-stress life events, such as a spouse’s death, divorce/separation or physical or verbal abuse, as well as social strain, were each independently linked with a 12% and 9% higher risk of coronary heart disease, respectively.

The Drexel study used data from a nationally representative sample of 80,825 postmenopausal women from the Women’s Health Initiative Observational Study, which tracked participants from 1991 to 2015, to find better methods of preventing cancer, heart disease and osteoporosis in women. In the current follow-up study, Drexel researchers evaluated the effect of psychosocial stress from job strain, stressful life events and social strain (through a survey), and associations among these forms of stress, on coronary heart disease.

Nearly 5% of the women developed coronary heart disease during the 14-year, seven-month study. Adjusting for age, time at a job, and socioeconomic characteristics, high-stress life events were associated with a 12% increased coronary heart disease risk, and high social strain was associated with a 9% increased risk of coronary heart disease. Work strain was not independently associated with coronary heart disease.

Coronary heart disease, the leading cause of death in the United States, occurs with the heart’s arteries become narrow and cannot bring sufficient oxygenated blood to the heart. The latest work builds on earlier studies linking psychosocial stress to coronary heart disease by finding out how job strain and social strain work together to compound disease risk.

“The COVID-19 pandemic has highlighted ongoing stresses for women in balancing paid work and social stressors. We know from other studies that work strain may play a role in developing CHD, but now we can better pinpoint the combined impact of stress at work and at home on these poor health outcomes,” said senior author Yvonne Michael, ScD, SM, an associate professor in the Dornsife School of Public Health. “My hope is that these findings are a call for better methods of monitoring stress in the workplace and remind us of the dual-burden working women face as a result of their unpaid work as caregivers at home .”

The study’s authors say that future studies should look at the effects of shift work on coronary heart disease and explore the effects of job demands according to gender.

“Our findings are a critical reminder to women, and those who care about them, that the threat of stress to human health should not go ignored,” said lead author Conglong Wang, PhD, a recent Dornsife graduate who conducted the research while at Drexel. “This is particularly pertinent during the stressors caused by a pandemic.”

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Optically active defects improve carbon nanotubes

The properties of carbon-based nanomaterials can be altered and engineered through the deliberate introduction of certain structural “imperfections” or defects. The challenge, however, is to control the number and type of these defects. In the case of carbon nanotubes — microscopically small tubular compounds that emit light in the near-infrared — chemists and materials scientists at Heidelberg University led by Prof. Dr Jana Zaumseil have now demonstrated a new reaction pathway to enable such defect control. It results in specific optically active defects — so-called sp3 defects — which are more luminescent and can emit single photons, that is, particles of light. The efficient emission of near-infrared light is important for applications in telecommunication and biological imaging.

Usually defects are considered something “bad” that negatively affects the properties of a material, making it less perfect. However, in certain nanomaterials such as carbon nanotubes these “imperfections” can result in something “good” and enable new functionalities. Here, the precise type of defects is crucial. Carbon nanotubes consist of rolled-up sheets of a hexagonal lattice of sp2 carbon atoms, as they also occur in benzene. These hollow tubes are about one nanometer in diameter and up to several micrometers long.

Through certain chemical reactions, a few sp2 carbon atoms of the lattice can be turned into sp3 carbon, which is also found in methane or diamond. This changes the local electronic structure of the carbon nanotube and results in an optically active defect. These sp3 defects emit light even further in the near-infrared and are overall more luminescent than nanotubes that have not been functionalised. Due to the geometry of carbon nanotubes, the precise position of the introduced sp3 carbon atoms determines the optical properties of the defects. “Unfortunately, so far there has been very little control over what defects are formed,” says Jana Zaumseil, who is a professor at the Institute for Physical Chemistry and a member of the Centre for Advanced Materials at Heidelberg University.

The Heidelberg scientist and her team recently demonstrated a new chemical reaction pathway that enables defect control and the selective creation of only one specific type of sp3 defect. These optically active defects are “better” than any of the previously introduced “imperfections.” Not only are they more luminescent, they also show single-photon emission at room temperature, Prof. Zaumseil explains. In this process, only one photon is emitted at a time, which is a prerequisite for quantum cryptography and highly secure telecommunication.

According to Simon Settele, a doctoral student in Prof. Zaumseil’s research group and the first author on the paper reporting these results, this new functionalisation method — a nucleophilic addition — is very simple and does not require any special equipment. “We are only just starting to explore the potential applications. Many chemical and photophysical aspects are still unknown. However, the goal is to create even better defects.”

This research is part of the project “Trions and sp3-Defects in Single-walled Carbon Nanotubes for Optoelectronics” (TRIFECTs), led by Prof. Zaumseil and funded by an ERC Consolidator Grant of the European Research Council (ERC). Its goal is to understand and engineer the electronic and optical properties of defects in carbon nanotubes.

“The chemical differences between these defects are subtle and the desired binding configuration is usually only formed in a minority of nanotubes. Being able to produce large numbers of nanotubes with a specific defect and with controlled defect densities paves the way for optoelectronic devices as well as electrically pumped single-photon sources, which are needed for future applications in quantum cryptography,” Prof. Zaumseil says.

Also involved in this research were scientists from Ludwig Maximilian University of Munich and the Munich Center for Quantum Science and Technology. 

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Coronavirus infections ‘a sixth of January peak’

ONS estimates that one-in-350 people in the UK currently have coronavirus

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Discovery could help lengthen lifespan of electronic devices

Ferroelectric materials are used in many devices, including memories, capacitors, actuators and sensors. These devices are commonly used in both consumer and industrial instruments, such as computers, medical ultrasound equipment and underwater sonars.

Over time, ferroelectric materials are subjected to repeated mechanical and electrical loading, leading to a progressive decrease in their functionality, ultimately resulting in failure. This process is referred to as ‘ferroelectric fatigue’.

It is a main cause of the failure of a range of electronic devices, with discarded electronics a leading contributor to e-waste. Globally, tens of millions of tonnes of failed electronic devices go to landfill every year.

Using advanced in-situ electron microscopy, the School of Aerospace, Mechanical and Mechatronic Engineering researchers were able to observe ferroelectric fatigue as it occurred. This technique uses an advanced microscope to ‘see’, in real-time, down to the nanoscale and atomic levels.

The researchers hope this new observation, described in a paper published in Nature Communications, will help better inform the future design of ferroelectric nanodevices.

“Our discovery is a significant scientific breakthrough as it shows a clear picture of how the ferroelectric degradation process is present at the nanoscale,” said co-author Professor Xiaozhou Liao, also from the University of Sydney Nano Institute.

Dr Qianwei Huang, the study’s lead researcher, said: “Although it has long been known that ferroelectric fatigue can shorten the lifespan of electronic devices, how it occurs has previously not been well understood, due to a lack of suitable technology to observe it.”

Co-author Dr Zibin Chen said: “With this, we hope to better inform the engineering of devices with longer lifespans.”

Observational findings spark new debate

Nobel laureate Herbert Kroemer once famously asserted “The interface is the device.” The observations by the Sydney researchers could therefore spark a new debate on whether interfaces — which are physical boundaries separating different regions in materials — are a viable solution to the unreliability of next-generation devices.

“Our discovery has indicated that interfaces could actually speed up ferroelectric degradation. Therefore, better understanding of these processes is needed to achieve the best performance of devices,” Dr Chen said.

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Masculine traits linked to better parenting for some dads

In some men, having traditional masculine characteristics such as competitiveness and adventurousness was linked to being better fathers to infants, a new study found.

But the men in this study — highly educated and from dual-earner couples — combined those stereotypically masculine traits with the belief that they should be nurturing, highly involved fathers.

The researchers were surprised that traits often seen as old-fashioned male stereotypes were linked to more positive parenting behaviors, said study lead author Sarah Schoppe-Sullivan, professor of psychology at The Ohio State University.

It suggests that some men are looking for new ways to be fathers, Schoppe-Sullivan said.

“These men are combining traditional aspects of masculinity with new nurturing ideals to create new fathering identities. They may be in the midst of transforming fatherhood.”

The study was published this week in the journal Psychology of Men and Masculinities.

The seven stereotypical masculine characteristics linked to positive parenting in this study — competitive, daring, adventurous, dominant, aggressive, courageous and stands up to pressure — are generally seen as positive traits, Schoppe-Sullivan noted.

But a negative masculine attitude that the researchers also measured in this study — hostile sexism — was not linked to positive parenting. In addition, the quality of fathers’ parenting of their infants was unrelated to the belief that men should be primary economic providers in the family.

The men in the study were participating in the New Parents Project, a long-term study led by Schoppe-Sullivan that is investigating how dual-earner couples adjust to becoming parents for the first time.

In the third trimester of their partners’ pregnancy, the expectant fathers completed a variety of questionnaires. They were asked to rate themselves on a four-point scale (not at all like me to very much like me) on the seven stereotypically masculine characteristics.

Hostile sexism was rated by asking male participants how much they agreed with 11 statements like “Feminists are making unreasonable demands of men.” Participants were also asked whether men or women should provide the majority of income for the family.

Their nurturing father role beliefs were measured by asking men to rate how much they agreed with nine statements like “Men should share with child care such as bathing, feeding and dressing the child.”

Nine months after the child was born, the researchers watched the fathers interact with their infants by themselves and with the mother. The researchers rated the fathers on their positive parenting behavior and on how well they co-parented together with mothers.

Results showed, as the researchers had predicted, that men who believed they should have a nurturing father role had higher-quality interactions with their child and were better at co-parenting with their partner.

But the researchers were surprised to find that the more men said they fit the stereotypical definition of “real men,” the more they were also rated as showing good parenting behavior.

“The fathers who see themselves as competitive and adventurous and the other masculine traits tended to be really engaged with their kids. They were not checked out,” Schoppe-Sullivan said.

It may be that men who used these traditionally masculine characteristics to succeed in their careers are trying to find ways to apply them to their jobs as parents.

“These dads may be saying that being a father is an important job, too, and I’m going to use the same traits that help me succeed at work to make me a successful father,” she said.

Schoppe-Sullivan emphasized that the fathers in this sample were highly educated and had partners who also worked. The findings here may not apply to all fathers.

But the results are encouraging, she said.

“If fathers can preserve the best of these stereotypically masculine characteristics, without the negatives like hostile sexism, that would be good for families.”

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Preseismic atmospheric radon anomaly associated with 2018 northern Osaka earthquake

The concentration of the radioactive element radon is known to change in the ground before and after earthquakes. Previous studies have shown elevated radon levels in the atmosphere before the mainshock of a large inland earthquake due to foreshock activity and slow slip.

But now, researchers from Tohoku University have revealed an anomaly in this phenomenon. Through the analysis of data before and after the 2018 Northern Osaka Earthquake, they discovered that the atmospheric radon concentration decreased.

The results of their research were published online in Scientific Reports on April 2, 2021.

“For the first time, we found a decrease in the atmospheric radon associated with seismic quiescence before the mainshock of an inland earthquake,” said professor Jun Muto of the Graduate School of Science at Tohoku University. Muto, who led the research group with professor Hiroyuki Nagahama, collaborated with Osaka Medical and Pharmaceutical University and Kobe Pharmaceutical University.

Observation in atmospheric radon concentration levels from the Osaka Medical and Pharmaceutical University showed a decline about one year before the earthquake, a trend that continued until June 2020. Seismic activity in the vicinity of the monitoring site also declined prior to the earthquake along with a reduced seismic activity after the mainshock for the entire Kansai region, excluding the aftershock area.

All of this suggests that radon levels did not increase after the earthquake. It also paints a more complicated picture of the radon and fluid movements that cause radon exhalation in the subsurface when large earthquakes occur.

“The discovery revealed that more processes are occurring before earthquakes than previously thought,” said Muto. “Further analysis of other earthquakes will lead to a better understanding of the physiochemical processes at play and help us use atmospheric radon concentrations to clarify various crustal movements correlated with major earthquakes.”

The research group has established atmospheric radon concentration measurement monitoring networks at radioisotope facilities across Japan. Monitoring is also expected be carried out at nuclear power plants.

Expansion of the monitoring network will help clarify the area and timing of radon anomalies, the geological characteristics that cause such anomalies, and the relationship with the different earthquake types. All of this will help realize a radon-based earthquake prediction system.

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Overseas health workers to get free UK visa extension, says Home Office

The Home Office says it will benefit 14,000 people, but unions ask why care workers are not included.

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