Tech

Our immune system not only protects us against infection, but also against cancer. This powerful protection is based in particular on the activation of special cells of the immune system, CD8+ T cells. These cells recognize infected or cancer cells and kill them specifically.

"The ability of the immune system and especially CD8+ T cells to eliminate cancer cells in tissues such as the lung, gut and liver is often limited in tumor patients," explains Percy Knolle, Professor of Molecular Immunology at the Technical University of Munich (TUM).

Administration of antibodies can reinvigorate the cancer patient´s immune response

Cancer cells send out signals that slow down the immune response against them. The knowledge of how tumor-specific immunity is restricted by these signals has led to the development of immunotherapies against cancer through what is referred to as checkpoint inhibition.

In this form of therapy, the signals emitted by cancer cells are inhibited and unleash cancer-specific immunity. Administration of antibodies that target these signals ("checkpoint inhibition") often can reinvigorate the patient´s immune response against the tumor.

Novel suppressive mechanism discovered that inhibits cancer-specific immune responses

The TUM research group led by Dr. Bastian Höchst and Prof. Percy Knolle at the Freising-Weihenstephan site and the University Hospital Klinikum rechts der Isar in Munich, together with researchers from the University of Heidelberg and the Otto von Guericke University Magdeburg as well as Yale University in the US, has discovered a novel mechanism of suppression that inhibits cancer-specific immune responses.

According to their recent publication, this suppression is mediated by a breakdown product from glucose metabolism. A particular type of myeloid immune cell (myeloid suppressor cells), which suppresses the activation of CD8+ T cells, are often found near and in tumor tissues. They are known to severely limit cancer-specific immunity.

"We were able to identify the excessive production of the breakdown product from glucose metabolism as a characteristic feature of suppressor cells in the tumor and at the same time to attribute inhibition of cancer-specific immunity to this suppressive metabolite," explained Dr. Bastian Höchst.

New method to activate immune cells to kill tumor cells

The researchers found that inhibition of cancer-specific CD8+ T cells is enforced by this suppressive metabolite through depletion of amino acids that are essential for the activation of immune cells. Such inhibited immune cells remain alive, but are arrested in hibernation-like state of low metabolic activity.

The researchers succeeded in developing methods, with which these "hibernating" immune cells can be re-awakened. The combination of "checkpoint inhibition" with neutralization of the suppressive metabolite led to a strong increase in cancer-specific immune response in experiments.

"These results will lead the way to development of new forms of immunotherapy against cancer," summarized Prof. Knolle.

Yale University researchers and colleagues in Hong Kong and China have developed an approach for rapidly tracking population flows that could help policymakers worldwide more effectively assess risk of disease spread and allocate limited resources as they combat the COVID-19 pandemic.

The approach, described in a study published early online on April 29 in the journal Nature, differs from existing epidemiological models by exploiting real-time data about population flows, such as phone use data and other "big data" sources that can accurately quantify the movement of people.

"This work shows that it is possible to very accurately forecast the timing, intensity, and geographic distribution of the COVID-19 outbreak based on population movement alone," said Yale's Nicholas A. Christakis, Sterling Professor of Social and Natural Science and a co-author of the study. "Moreover, by tracking population flows in real time, our model can provide policymakers and epidemiologists a powerful tool to limit an epidemic's impact and save lives."

In developing the model, the researchers used nationwide mobile-phone geo-location data to track about 11.5 million occasions of people transiting through Wuhan, a prefecture city in China's Hubei Province, between Jan. 1 and Jan. 24, 2020 -- a period covering the run-up to the Chinese Lunar New Year and the annual chunyun mass migration in China. People moved through Wuhan to 296 prefectures in 31 provinces and regions throughout the country. The researchers linked the population-flow data, which was provided by a major national wireless telecommunications carrier, to COVID-19 infection counts, provided by the Chinese Center for Disease Control and Prevention (Chinese CDC), by location and time at the prefecture level.

Their analysis demonstrates the effectiveness of the quarantine imposed on Wuhan on Jan. 23. By the end of the day on Jan. 24, movement out of the city had almost completely ceased, according to their findings.

The researchers found that the distribution of people leaving Wuhan accurately predicted the relative frequency of subsequent COVID-19 infections across China through Feb. 19, 2020. Researchers also developed a "risk source" model that leveraged population flow data to accurately forecast confirmed cases and identify places at risk of high transmission rates during the outbreak's early stages.

Their analysis also corroborates the data released by the Chinese CDC through Feb. 19 (for the prefectures outside of Wuhan itself) because it shows that a totally independent source of information -- the telecom carrier -- is very well correlated with official COVID-19 case counts.

"If there are more confirmed cases than expected ones, there is a higher risk of community spread. If there are fewer expected cases than reported, it means that the city's preventive measures are particularly effective or it can indicate that further investigation by the central authorities is needed to eliminate possible risks from inaccurate measurement," said Jayson Jia, associate professor of marketing in the Faculty of Business and Economics at the University of Hong Kong, and lead author of the study.

"What is innovative about our approach is that we use misprediction to assess the level of community risk. Our model accurately tells us how many cases we should expect given travel data. We contrast this against the confirmed cases using the logic that what cannot be explained by imported cases and primary transmissions should be community spread," Jia added.

The new model can be applied using any dataset that accurately captures people's movements, such as train ticketing or car tolling data, researchers noted, meaning that policymakers worldwide could use it to inform efforts to contain the virus' spread if data regarding population movements is available.

"People spread contagious diseases when they move," said Christakis, director of the Yale Institute for Network Science. "By accurately capturing population movements over time, we can predict how a contagion will spread geographically and use data-analytic techniques to help control it before a devastating epidemic erupts or re-erupts."

WASHINGTON, April 28, 2020 -- Laboratory blood tests are often done by forcing samples through small channels. When the channels are very small, as in microfluidic devices, red blood cells (RBCs) are deformed and then relax back to their original shape after exiting the channel. The way the deformation and relaxation occur depends on both the flow characteristics and mechanical properties of the cell's outer membrane.

In this week's issue of the journal Biomicrofluidics, from AIP Publishing, a method to characterize the shape recovery of healthy human RBCs flowing through a microfluidic constricted channel is reported. This investigation revealed a coupling between the cell's mechanical properties and the hydrodynamic properties of the flow. In addition, the method could distinguish between healthy RBCs and those infected by the malaria parasite. This suggests a possible new technique for diagnosing disease.

The microfluidic device consisted of a narrow channel interspersed by a succession of sawtooth-shaped wider areas. A solution of RBCs is pumped through the system by applying pressure from one end. As the cells travel through the channel, they are observed with a microscope. The images are captured with a high-speed camera and sent to a computer for analysis.

When an RBC enters a narrow channel, it takes on a parachutelike shape. When it exits into a wide region, it elongates in the direction of the flow until it meets the next widening and is again stretched by the flow.

At the final exit, two different shape recovery behaviors were observed, depending on the flow speed and viscosity of the medium. At high flow speed and viscosity, the cells get stretched upon their last exit from the channel and then recover their original shapes. At lower speed and viscosity, however, the parachutelike shape is recovered directly upon exiting.

The investigators found that the hydrodynamic conditions at which the transition between these two different recovery behaviors occurs depend on the elastic properties of the RBC.

Co-author Magalie Faivre said, "Although the time necessary for the cells to recover their shape after exiting the channel was shown to depend on the hydrodynamic conditions, we have demonstrated that, at a given stress, this recovery time can be used to differentiate healthy from Plasmodium falciparum-infected RBCs." Plasmodium falciparum is one of the parasites that cause malaria.

The investigators are seeking to expand their study to find a way to detect "signatures" for other types of diseases.

"We are currently evaluating if our approach is able to discriminate the alteration of different structural components of the RBC membrane," said Faivre. "To do so, we are studying RBCs from patients with malaria, sickle cell anemia and hereditary spherocytosis."

WASHINGTON, April 28, 2020 -- A device which simulates borehole ballooning, a detrimental side effect of deep-water drilling operations, is expected to ensure safe and efficient operations. If not prevented, borehole ballooning can lead to irreversible damage and serious drilling accidents, which can result in reservoir pollution and huge economic loss.

In a recent issue of the Review of Scientific Instruments, from AIP Publishing, researchers from the China University of Petroleum-Beijing present a device that can simulate this dangerous phenomenon in the hopes of preventing it.

"In order to promote the development of deep-water drilling technology and ensure the safe and efficient exploitation of deep-water oil and gas, we have conducted research on the problems encountered in deep-water drilling processes, and the borehole ballooning is one of them," said author Reyu Gao.

Borehole ballooning is reversible mud gains and losses to the wellbore that occur during drilling. Increased understanding and data on the phenomenon can help scientists develop preventative response measures to counteract it.

Unlike previous research, which largely focused on numerical modeling, the authors' research included experimental results.

"Most research into borehole ballooning has been theoretical, with few experiments," said Gao. "Our device is the first professional device capable of simulating and studying the borehole ballooning under different conditions."

The device, which is made up of four individual units, can simulate conditions like different fracture opening pressures, rock types, and mud circulation pressures. Its sections include the displacement unit, the triaxial clamping unit, the back-pressure unit, and the control and data acquisition system.

"According to the current research, the main mechanism causing borehole ballooning is the opening and closing of the fracture network around the wellbore caused by wellbore pressure fluctuations. Therefore, based on this mechanism, we first designed the core unit of the device, the triaxial clamping unit, which can simulate the opening and closing of fractures," said Gao.

The researchers proved their device was able to accurately simulate the effects of borehole ballooning through experiments, and they expect these experiments to be able to validate theoretical research on the topic.

WASHINGTON, D.C. and SAN DIEGO, CA - About 1 in 7 Americans say they would avoid seeking medical care if they experienced key symptoms associated with COVID-19 out of fear of the potential cost. Another six percent - representing about 15 million people - report that they or a family member have been denied medical care for some other health issue due to heavy volume brought on by the coronavirus outbreak.

The findings, released today by the nonprofit West Health and Gallup as part of a series on the rising cost of healthcare in the U.S., come from a nationally representative survey of 1,017 U.S. adults conducted between April 1 and 14. New results from a separate survey on attitudes toward prescription drug prices and the Trump administration's efforts to lower are outlined below.

When presented with a scenario in which they experience a fever and a dry cough, telltale signs of COVID-19, 14% of U.S. adults say they would avoid seeking medical attention due to cost. Even when asked to specifically suspect themselves infected with coronavirus, 9% would still avoid treatment, suggesting gaps in insurance coverage, poor finances or incomplete knowledge of the key symptoms of COVID-19. More than 20% of adults under 30, non-whites, those with a high school education or less and those in households with incomes under $40,000 per year were the groups most likely to avoid care.

"Millions of Americans, even in the face of a disease that has brought a country to its knees, would forgo care due to the potential expense and still others may not be clear on the common symptoms of COVID-19," said Tim Lash, chief strategy officer for West Health. "While physicians and healthcare workers are doing courageous and lifesaving work, the pandemic magnifies the longstanding perils and flaws of a high cost healthcare system in need of reform."

Avoidance of care for any reason is a cause for concern and a public health challenge. As are the denials of care, which millions of Americans are experiencing as healthcare workers focus on COVID-19. Those living in the Northeast region (11%) are the most likely to report having been denied care, followed by the West (8%). Just 5% in the South and 3% in the Midwest report the same, likely reflecting regional differences in COVID-19 diagnoses and associated hospitalizations. New York state has by far the greatest number of confirmed cases in the U.S., followed by New Jersey, Massachusetts and Pennsylvania - all Northeast region states.

Although race does not strongly relate to be being denied care, income level is strongly inversely related. While 3% of those with annual household incomes exceeding $100,000 report such occurrences, this jumps to 11% of those with incomes of under $40,000 - nearly four times higher.

The survey did not identify healthcare consumers' reasons for seeking care - respondents could have been feeling symptoms related to COVID-19, experiencing symptoms related to other conditions or attending routine treatments.

"These new findings align with previous research by West Health and Gallup on the impact of high healthcare costs in the U.S.," said Dan Witters, Gallup senior researcher. "Last year, over 13% of respondents, representing more than 30 million Americans, reported having a friend or family member who died in the last five years after not being able to afford necessary care. Add to that the challenges associated with COVID-19, and Americans find themselves in a quagmire as many of them turn to a system they can't afford or that can't accommodate them."

66% Report Increase in Cost of Prescription Drugs

In new results from a separate survey, 66% of U.S. adults report prescription drug prices have increased either "a little" or "a lot" since 2017, the first year of the Trump administration. Dovetailing with these results are perceptions of Trump's progress at curtailing rising drug prices, with 31% reporting a "great deal" or a "fair amount." This marks a slight improvement over the 27% who saw progress in September.

The overall improvement in those seeing at least a fair amount of progress, however, was driven by independents (+6 points to 28%) and Democrats (+5 points). Republicans seeing progress dropped by seven percentage points to 56%, a statistically significant decline.

As a proposed means to lower prescription drug prices, the U.S. House late last year passed House Bill H.R. 3, also known as the Elijah E. Cummings Lower Drugs Costs Now Act. When told that the legislation would allow federal regulatory agencies to negotiate drug prices with drug companies, 75% of U.S. adults support putting it up for a vote in the U.S. Senate. Partisans are closely aligned, with 72% of Republicans and 77% of Democrats supporting movement. Seventy-six percent of independents agree.

Data on prescription drug prices come from a nationally representative survey of 1,020 U.S. adults conducted between Feb. 17 and 28.

Full analyses of findings from both surveys, including methodology statements, can be found at the links below:

In U.S., 14% With Likely COVID-19 to Avoid Care Due to Cost

In U.S., 66% Report Increase in Cost of Prescription Drugs

Proteins are composed of amino acids connected by amide bonds. The amide bond exhibits high chemical stability and has a planar structure around the bond. Although the high stability of amide bond is indispensable to maintain protein functions, it is problematic to convert the building block into some other molecular species by selective dissociation of a relevant amide bond. There have been attempted to control reactivity of a specific amide bond with selective twisting of the bond by complicated chemical modifications. Some model compounds with twisted amide bonds have been produced by multi-step organic synthesis and their high reactivity has been demonstrated. It is presumed that the high reactivity of these twisted amide bonds is also used in vivo. Some proteins seem to be selectively cleaved by twisting specific amide bonds during autolysis and splicing. These proteins, unlike artificially synthesized model compounds, are supposed to use non-covalent interactions to twist their amide bonds. The researchers at the University of Tokyo and Institute for Molecular Science have fabricated for many years their molecular cages, which are self-assembled by the non-covalent interactions. They applied their molecular cages to confine amide molecules, which can be regarded as analogs of small pieces of proteins, and squeezed the amide bonds by pressurizing them inside their cage.

The researchers have reported in the present paper that amide bonds, which have planar structures and are inert in free space, can be twisted and the amide compounds can be activated by confining them into their molecular cage (shown in Figure). When target amide compounds and the molecular cage are mixed and heated in an aqueous solution, the cage confines the amide compounds. Single-crystal X-ray structure analysis revealed that two amide compounds with twisted structures are confined in the cage. The twist angle around the amide bonds was found to reach 34 degrees. The reaction rate of hydrolysis of the twisted target was accelerated by a factor of five. The researchers succeeded in creating a new artificial enzyme of unexploited mechanism that it confines and twists the target molecules to activate a specific chemical bond.

The researchers also succeeded in altering the reactivity of target molecules by confining "stuffing molecules", which are not involved in the reaction, together with the targets in the cage, thereby precisely controlling the degree of twisting of the amide bonds. Without the stuffing molecule, the two of target amides are confined in one cage. One of the two targets is twisted and another one remains planar. In contrast, when conical stuff is mixed and then involved together with the target in one cage, the target remains planar. When a planar stuffing molecule is involved with the target, the stuff changes the shape of target into a twisted structure. The researchers investigated the reaction rates of hydrolysis in the two cases and found that the planar stuff (twisted target) accelerate the rate by 14 times, while the conical stuff (planar target) accelerated the rate by three times. The stuffing molecules allows us to tune the reaction rate precisely. This is an unprecedented achievement which has never been found in previous researches. This research gives us a novel method for the activation of inert molecules and can be applied to a variety of organic reactions.

The researchers showed that the amide molecules can be activated by twisting inside the cage without cumbersome chemical modification processes. "We are looking for new type of cages which can activate the targets with higher efficiency and apply them to other categories of target molecules. With our new cages, we will develop the novel activation method of inert molecules. In the future, our cages will be used as catalysts, which selectively squeeze and activate a specific bond of a target molecule and also as activation agents for prodrugs working in our body," said Fujita.

RICHLAND, Wash. -- The same material you'll find at the tip of a pencil--graphite--has long been a key component in today's lithium-ion batteries. As our reliance on these batteries increases, however, graphite-based electrodes are due for an upgrade. For that, scientists are looking to the element at the heart of the digital revolution: silicon.

Scientists at the U.S. Department of Energy's Pacific Northwest National Laboratory have come up with a novel way to use this promising but problematic energy storage ingredient. Silicon, used in computer chips and many other products, is appealing because it can hold 10 times the electrical charge per gram compared to graphite. The trouble is, silicon expands greatly when it encounters lithium, and it is too weak to withstand the pressure of electrode manufacturing.

To tackle these issues, a team led by PNNL researchers Ji-Guang (Jason) Zhang and Xiaolin Li developed a unique nanostructure that limits silicon's expansion while fortifying it with carbon. Their work, which was recently published in the journal Nature Communications, could inform new electrode material designs for other types of batteries and eventually help increase the energy capacity of the lithium-ion batteries in electric cars, electronic devices, and other equipment.

Taking the cons out of silicon

A conductive and stable form of carbon, graphite is well suited to packing lithium ions into a battery's anode as it charges. Silicon can take on more lithium than graphite, but it tends to balloon about 300 percent in volume, causing the anode to break apart. The researchers created a porous form of silicon by aggregating small silicon particles into microspheres about 8 micrometers in diameter--roughly the size of one red blood cell.

"A solid material like stone, for example, will break if it expands too much in volume," Zhang said. "What we created is more sponge-like, where there is space inside to absorb the expansion."

The electrode with porous silicon structure exhibits a change in thickness of less than 20 percent while accommodating twice the charge of a typical graphite anode, the study found. However, unlike previous versions of porous silicon, the microspheres also exhibited extraordinary mechanical strength, thanks to carbon nanotubes that make the spheres resemble balls of yarn.

Super-strong microspheres

The researchers created the structure in several steps, starting by coating the carbon nanotubes with silicon oxide. Next, the nanotubes were put into an emulsion of oil and water. Then they were heated to boiling.

"The coated carbon nanotubes condense into spheres when the water evaporates," said Li. "Then we used aluminum and higher heat to convert the silicon oxide into silicon, followed by immersion in water and acid to remove by-products." What emerges from the process is a powder composed of the tiny silicon particles on the surface of carbon nanotubes.

The porous silicon spheres' strength was tested using the probe of an atomic force microscope. The authors found that one of the nanosized yarn balls "may yield slightly and lose some porosity under very high compressing force, but it will not break."

This augurs well for commercialization, because anode materials must be able to handle high compression in rollers during manufacturing. The next step, Zhang said, is to develop more scalable and economical methods for making the silicon microspheres so that they can one day make their way into the next generation of high-performance lithium-ion batteries.

One of the greatest challenges facing humanity is how to grow more food while reducing the negative impacts of agriculture upon the environment. Our ability to do so requires ever-more efficient and sustainable agricultural practices. The promising news is that researchers have found out that the spatial pattern in which a farmer sows their crops is an important determinant of what they will reap.

"In the vast majority of cases, higher yields and fewer weeds are the result of sowing crops in a more uniform, grid-like pattern, where each plant is equidistant from its neighbouring plants, both within and between rows," says Professor Jacob Weiner of the University of Copenhagen's Department of Plant and Environmental Sciences.

Professor Weiner and his colleagues from Northeast Agricultural University in China conducted a large metastudy of research in the area to discover the impact of uniform spatial patterns on crop yields and weed growth. The study, now published in the prestigious serial Advances in Agronomy, demonstrated that a uniform seeding pattern resulted in higher yields in 76% of trials, and fewer weeds in 73% of trials.

In particular, the researchers looked at three of the world's most widely-cultivated crops: wheat, maize and soybean. In many studies, yields were roughly 20% higher, while one study yielded 60% more wheat and another, up to 90% more soybeans. With regards to weed growth, several studies resulted in more than a 30% reduction in weeds when traditional, less precise sowing was replaced by the uniform sowing pattern.

"Our own research has demonstrated the positive effects of the uniform sowing of wheat when weeds are present, but the new study shows that this benefit extends to other crops, both with and without competition from weeds" says Professor Weiner.

Win-win for the environment

Today, a typical seeding machine sows in a fairly precise distance between rows. However, within each row, the distance between seeds is random, meaning that some plants have close neighbours, while others have distant ones.

Conversely, when seeds are sown in uniform grid patterns, roots spread and occupy soil space faster, while more readily and efficiently absorbing nutrients. This helps to reduce the release of nutrients such as nitrogen.

"From an environmental perspective, it's win-win. There is less nitrogen runoff, and herbicide can be reduced because there are fewer weeds to contend with. This ability to increase yields and mitigate environmental impacts contributes to more sustainable agriculture," according to the the professor.

Above ground, the uniform grid pattern is advantageous because crop plants shade one another less during the early part of the growing season. One study estimateded that crop leaves covered the ground several weeks sooner when sown in a uniform sowing pattern.

"It's a bit like a forest plantation, where trees are planted in a uniform pattern. In this way, there is nothing new to this principle. It just hasn't been seen as important for crops as it is for trees. People didn't believe that a sowing pattern could have such a significant impact for crops. But we were able to conclude that it does," says Jacob Weiner.

Technically, this type of precision sowing has been a challenge.

"But now, there are machines suited for the job and new ones are constantly being developed. This applies to both precision seeders and robots. You might pay more for the machine, but it's a one-time expense that pays itself off," says Jacob Weiner.

FACTS:

In the vast majority of cases, an even distribution of crops within rows results in higher yields and fewer weeds. When the distance between rows is reduced as well, even greater outcome are possible.

The study also demonstrates that uniform sowing patterns are less effective in drier areas, while more effective in wetter ones.

The study was conducted by Ping Lu and Baiwen Jiang from Northeast Agricultural University in Harbin, China and Jacob Weiner from the Department of Plant and Environmental Sciences at the University of Copenhagen.

The study is published in the acclaimed serial, Advances in Agronomy.

Surface chemistry of chainmail links from the wrecked warship Mary Rose analysed using state-of-the-art X-ray facility

Team led by Universities of Warwick and Ghent reveals composition of the armour and extent of corrosion since recovery from the seabed

Traces of lead and gold hint at further history to be unearthed

Research confirms the effectiveness of the conservation techniques used

21st century X-ray technology has allowed University of Warwick scientists to peer back through time at the production of the armour worn by the crew of Henry VIII's favoured warship, the Mary Rose.

Three artefacts believed to be remains of chainmail recovered from the recovered hull have been analysed by an international team of scientists led by the Universities of Warwick and Ghent using a state-of-the-art X-ray facility called XMaS (X-ray Materials Science) beamline.

They analysed three brass links as part of continuing scientific investigations into the artefacts recovered during the excavation of the wreck in the Solent. These links have often been found joined to make a sheet or a chain and are most likely to be from a suit of chainmail armour. By using several X-ray techniques available via the XMaS beamline to examine the surface chemistry of the links, the team were able to peer back through time to the armour's production and reveal that these links were manufactured from an alloy of 73% copper and 27% zinc.

Emeritus Professor Mark Dowsett from the University of Warwick's Department of Physics said: "The results indicate that in Tudor times, brass production was fairly well controlled and techniques such as wire drawing were well developed. Brass was imported from Ardennes and also manufactured at Isleworth. I was surprised at the consistent zinc content between the wire links and the flat ones. It's quite a modern alloy composition."

The exceptionally high sensitivity analysis revealed traces of heavy metals, such as lead and gold, on the surface of the links, hinting at further history to the armour yet to be uncovered.

Professor Dowsett explains: "The heavy metal traces are interesting because they don't seem to be part of the alloy but embedded in the surface. One possibility is that they were simply picked up during the production process from tools used to work lead and gold as well. Lead, mercury and cadmium, however, arrived in the Solent during WW2 from the heavy bombing of Portsmouth Dockyard. Lead and arsenic also came into the Solent from rivers like the Itchen over extended historical periods.

"In a Tudor battle, there might be quite a lot of lead dust produced by the firing of munitions. Lead balls were used in scatter guns and pistols, although stone was used in canon at that time."

The Tudor warship the Mary Rose was one of the first warships that Henry VIII ordered not long after he ascended to the throne in 1509. Often considered to be his favourite, on 19 July 1545 it sank in the Solent during a battle with a French invasion fleet. The ship sank to the seabed and over time the silts covered and preserved its remains as a remarkable record of Tudor naval engineering and ship board life.

In 1982 the remaining part of the hull was raised and is now housed in the Mary Rose Museum in Portsmouth alongside many thousands of the 19,000 artefacts that were also recovered, many of which were remarkably well preserved by the Eocene clays.

After recovery, the three artefacts were subjected to different cleaning and conservation treatments to prevent corrosion (distilled water, benzotriazole (BTA) solution, and cleaning followed by coating with BTA and silicone oil). This research also analysed the surface chemistry of the brass links to assess and compare the levels of corrosion between the different techniques, finding that all had been effective at preventing corrosion since being recovered.

Professor Dowsett added: "The analysis shows that basic measures to remove chlorine followed by storage at reduced temperature and humidity form an effective strategy even over 30 years."

XMaS is owned by the Universities of Liverpool and Warwick and is located in Grenoble, France, at the European Synchrotron Radiation Facility (ESRF). It works with over 90 active research groups, representing several hundred researchers, in diverse fields ranging across materials science, physics, chemistry, engineering and biomaterials and contributes to societal challenges including energy storage and recovery, tackling climate change, the digital economy and advances in healthcare.

It is a National Research Facility and is currently undergoing a major upgrade thanks to £7.2million funding from the Department of Business, Innovation and Skills through the Engineering and Physical Sciences Research Council (EPSRC).

Professor Mieke Adriaens, Head of the Electrochemistry and Surface Analysis Group at Ghent University said: "XMaS is extremely versatile and flexible in the analytical strategies which can be devised and implemented. What's more, the beamline scientists are amongst the best we've encountered anywhere. It is fascinating to examine ancient technology using specially developed analytical methods which can then be applied to modern materials too. It was also a real privilege to be allowed access to these unique artefacts and to play a part in unravelling their story."

Professor Eleanor Schofield, Head of Conservation at the Mary Rose: "This study clearly shows the power of combining sophisticated techniques such as those available at a synchrotron source. We can glean information not only on the original production, but also on how it has reacted to being the marine environment and crucially, how effective the conservation strategies have been.

Co-author Professor Pam Thomas, Pro-Vice-Chancellor for Research at the University of Warwick, said: "We are very pleased that researchers at Warwick are continuing to put our expertise in Analytical Sciences at the forefront of research on important historical artefacts. The long tradition of X-ray scattering and diffraction science within the Department of Physics at Warwick continues to give high-quality data and leads to penetrating insight across a wide range of scientific problems. It is testament both to the expertise at the XMaS beamline of ESRF and in the X-Ray Diffraction Research Technology Platform (RTP) at Warwick."

Sensitive X-ray detectors are essential for medical radiography, industrial inspection and security screening. However, commercially available X-ray instruments require high dosages for imaging. Further lowering the radiation dose will reduce health risks to patients; and will also increase the frequency with which X-ray images can safely be acquired, ultimately paving the way toward truly personalized patient care.

Researchers from China Academy of Engineering Physics, Nanjing University and University of Victoria demonstrated ultra-sensitive and stable X-ray detectors by using a new kind of 0D MA3Bi2I9 single-crystals. The disconnecting of the (Bi2I9)3- units in the lattice leads to a high activation energy (Ea) for ion migration (0.46 eV) and is also accompanied by a low dark carrier concentration (~ 10 6 cm-3). The suppressed ion migration and lowered dark carrier concentration enable the desirable combination of high sensitivity, low LoD, and stable operation. X-ray detectors with a low LoD of 0.62 nGyair s-1 was achieved with a 100 kVp tungsten-target X-ray tube, which approaches the background radiation on Earth (~0.1 nGyair s-1), and is significantly lower than the dose rate required for X-ray diagnostics (5.5 μGyair s-1). Additionally, the reported X-ray sensitivity of 10,620 μC Gyair-1 cm-2 is comparable to the values obtained in 3D perovskite detectors (1.1 × 10 4 μC Gyair-1 cm-2 for MAPbI3 and 2.1 × 10 4 μC Gyair-1 cm-2 for hybrid MAPbBr3/Si) and 2D perovskite detectors (8,400 μC Gyair-1 cm-2 for (NH4)3Bi2I9). It is worth noting that, unlike 2D hybrid Bi halide perovskites that cannot obtain low LoD and high sensitivity in the same direction, 0D MA3Bi2I9 X-ray detectors achieve simultaneously low LoD and high X-ray sensitivity in the out-of-plane transport mode. The 0D perovskite X-ray detectors exhibit stable operation even under high applied biases up to 120 V. No deterioration in detection performance was observed following an X-ray irradiation dose of ~23,800 mGyair, equivalent to > 200,000 times of the dose used in acquiring commercial X-ray chest radiographs.

The advance presented herein provides a promising X-ray detector candidate in X-ray imaging and medical applications. This work was published in Journal of Energy Chemistry.

Simultaneous deep brain stimulation (DBS) and functional magnetic resonance imaging (fMRI) is critical for understanding the functional neural networks and the therapeutic effects and mechanisms of DBS therapies. Conventional DBS electrodes typically lead to severe distortion of the surrounding magnetic field, which creates large artifacts in MR images and thus impedes the functional investigation of DBS-fMRI.

Recently, collaboration between Dr. Duan Xiaojie's group (Department of Biomedical Engineering, College of Engineering, Peking University) and Dr. Liang Zhifeng's group (Institute of Neuroscience, Center for Excellence in Brain Science and Intelligence Technology, CAS) has led to a novel MRI compatible, graphene fiber DBS electrode. Using a Parkinsonian rat model, this novel electrode achieved full activation pattern mapping by simultaneous deep brain stimulation and fMRI, and revealed close relationship between fMRI activation and DBS therapeutic improvement.

This novel graphene fiber DBS electrode has 70 times more charge injection capacity than electrodes made of platinum-iridium (PtIr), which is the material most commonly used in clinical DBS, and exhibits much smaller artifacts in both T2 weighted structural images and T2* weighted functional echo planar images (Figure 1) at a high field of 9.4-Tesla. In addition, this electrode shows high stability under continuous overcurrent pulsing. Using this graphene fiber DBS electrode, subthalamic nucleus (STN) was stimulated as the DBS target in a Parkinsonian rat model, which significantly improved rats' motor ability and reduced the motor deficit.

The above unique advantage of this novel DBS electrode enabled full activation pattern mapping using simultaneous DBS and fMRI, including the DBS target (STN) itself. The fMRI activation amplitudes of several key brain regions were found to be closely associated with mobile speed improvement, including STN, motor cortex, internal globus pallidus (GPi), external globus pallidus (GPe) and caudate putamen (CPu) (Figure 2). The above result suggests that the therapeutic effect of STN DBS in Parkinson's disease may be achieved by both orthodromic and antidromic effect of electrical stimulation.

This work was published by Nature Communications on April 14, 2020 (DOI: 10.1038/s41467-020-15570-9). Graduate students Zhao Siyuan and Li Gen from Peking University were co-first authors, and Dr. Duan Xiaojie and Dr. Liang Zhifeng were co-corresponding authors. This work was supported by National Natural Science Foundation of China, the National Basic Research Program of China.

Recently, Professor Zhan Xiaowei's group from the College of Engineering at Peking University made new progress in non-fullerene acceptors for organic solar cells (OSCs). They developed a new fluorinated fused-ring electron acceptor (FREA) with 3D stacking and exciton and charge transport (Adv. Mater., DOI: 10.1002/adma.202000645).

In 2015, the Zhan group pioneered the concept of FREA and invented the landmark molecule ITIC (Adv. Mater., 2015, 27, 1170-1174, cited 1590 times). In 2017, they firstly introduced fluorinated 2-(3-oxo-2,3-dihydroinden-1-ylidene) -malononitrile, 1FIC and 2FIC, in FREAs (J. Am. Chem. Soc., 2017, 139, 1336-1343, cited 547 times; Adv. Mater., 2017, 29, 1700144, cited 549 times). Now, all the best non-fullerene acceptors are based on 1FIC/2FIC.

Most recently, they proposed a new design strategy to construct FREAs via fluorination of both end-groups and side-chains. Close 3D stacking network is formed due to 3D non-covalent interactions caused by F atoms on both end-groups and side-chains, which is beneficial to efficient 3D exciton and charge transport. The OSCs based on FINIC with fluorinated end-groups and side-chains show an efficiency of 14.0%, much higher than that of the nonfluorinated INIC-based cells (5.1%).

The research work was supported by the National Nature Science Foundation of China and Basic Research Promotion Project of Peking University.

The extreme cold, harsh environment and constant hunt for food means that Arctic animals have become specialists in saving energy. Now, researchers at Lund University in Sweden have discovered a previously unknown energy-saving method used by birds during the polar night.

Researchers from Lund University and the University of Tromsø have examined the immune system strength of the Svalbard rock ptarmigan in the Arctic. This bird lives the farthest up in the Arctic of any land bird, and the researchers have investigated how the immune response varies between winter and late spring.

"We have discovered that the birds reduce how much they spend on keeping their own immune defence system up and running during the five months of the year when it is dark around the clock, probably to save energy. Instead, they use those resources on keeping warm and looking for food. When daylight returns, their immune response is strengthened again," says Andreas Nord, researcher at Lund University.

The researchers found that when the birds become ill in mid-winter, their energy consumption drops compared to when they are healthy. However, when the birds become ill in late spring, their energy consumption increases instead.

"A weaker immune system is probably a part of all the adaptations that Arctic animals use to save energy in winter. The risk of being infected by various diseases so far north is less in winter than when it becomes warmer towards summer", says Andreas Nord.

When Svalbard rock ptarmigan save energy in this manner, they do so by weakening an already weak immune system. According to the researchers, this is probably due to the fact that the species evolved in the Arctic where there has been less of a need for a very strong immune defence system.

"This may have negative consequences when the climate changes and migratory birds arrive earlier in the Arctic and leave later. More and more tourists also come ashore in places where people have not set foot before. Such a scenario paves the way for an increased risk of disease and may be a threat to animals that have evolved in the Arctic where a strong immune defence system might not have been needed", Andreas Nord concludes.

The design of materials with high capacity, excellent rate capability and long cycle life is one of the major challenges for the rechargeable lithium ion batteries (LIBs). Among the virous anode materials, TiO2 stands out due to its nontoxicity, high abundance, high activity, safe operation, electrochemical and structural stability. However, the kinetics of Li+ insertion-extraction and the electrochemical performance of TiO2 are always limited by slow Li+ diffusion and charge transport as well as the low electrode/electrolyte contact area. Various efforts have been made to solve these problems in recent reports, such as assembling low-dimensional nanostructures with (001) facets and combining TiO2 with conductive supports. However, the high energy of (001) facets easily results in a tight aggregation of the TiO2 nanosheets and the internal electrochemical processes have not been studied in detail. In this work, it reported an unprecedented lithium storage and electrochemical performance of a nanosheet-constructed hierarchically porous TiO2/rGO hybrid architecture.

In the synthesis, TiF4 was used as a structure-directing agent to ensure the formation and exposure of (001) faceted TiO2 nanosheets and the flexible graphene oxide could regulate assembly of the nanosheets. The density functional theory (DFT) calculations evidenced that the energy barrier of Li+ entering into the (001) surface of anatase TiO2 was the lowest and the Li+ was easier to migrate across the (001) surface. The resulting hierarchically porous NSTiO2/rGO hybrid structure offered a high and stable surface area (304.5 m2 g-1) and exhibited an excellent reversible capacity of 250 mAh g-1 at 1 C (1 C = 335 mA g-1). On one hand, it could intensively increase the active sites for Li+ insertion-extraction, its porous structure would significantly facilitate electrolyte permeation and largely endurance volume expansion. On the other hand, its thinner nanosheets constructed porous network could notably shorten the path length for Li+ and increase the charge transfer, leading to a highly enhanced capacity. The discharge-charge profiles at various current densities demonstrated that the (001) facets of TiO2 facilitate and dominate the Li+ insertion-extraction at low current densities ( 1 C), the high specific surface area and porosity in the hierarchically porous architecture dominated the Li+ insertion-extraction process. Electrochemical impedance spectroscopy (EIS) was used to confirm stable surface layer resistance Rs at the surface layer and inverse charge-transfer resistance Rct in the electrode/electrolyte interface during the discharge-charge cycling process. In addition, in-situ XRD, SEM and TEM measurements were also adopted to detect the electrochemical transitions of NSTiO2/rGO anode material, which further demonstrated structural stability and the formation of cubic Li2Ti2O4 nanocrystallites.

This work was reported in National Science Review, entitled "Unprecedented and highly stable lithium storage capacity of (001) faceted nanosheet-constructed hierarchically porous TiO2/rGO hybrid architecture for high performance Li ions battery" by Prof. Bao-Lian Su and Prof. Yu Li in State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology. The researchers envision that this hierarchically porous NSTiO2/rGO micro/nanostructure hybrid can be used as a very promising anode material for industrial application in high-performance LIBs and may be employed in other applications.

Synthetic antibodies constructed using bacterial superglue can neutralise potentially lethal viruses, according to a study published on April 21 in eLife.

The findings provide a new approach to preventing and treating infections of emerging viruses and could also potentially be used in therapeutics for other diseases.

Bunyaviruses are mainly carried by insects, such as mosquitoes, and can have devastating effects on animal and human health. The World Health Organization has included several of these viruses on the Blueprint list of pathogens likely to cause epidemics in humans in the face of absent or insufficient countermeasures.

"After vaccines, antiviral and antibody therapies are considered the most effective tools to fight emerging life-threatening virus infections," explains author Paul Wichgers Schreur, a senior scientist of Wageningen Bioveterinary Research, The Netherlands. "Specific antibodies called VHHs have shown great promise in neutralising a respiratory virus of infants. We investigated if the same antibodies could be effective against emerging bunyaviruses."

Antibodies naturally found in humans and most other animals are composed of four 'chains' - two heavy and two light. VHHs are the antigen-binding domains of heavy chain-only antibodies found in camelids and are fully functional as a single domain. This makes VHHs smaller and able to bind to pathogens in ways that human antibodies cannot. Furthermore, the single chain nature makes them perfect building blocks for the construction of multifunctional complexes.

In this study, the team immunised llamas with two prototypes of bunyaviruses, the Rift Valley fever virus (RVFV) and the Schmallenberg virus (SBV), to generate VHHs that target an important part of the virus' infective machinery, the glycoprotein head. They found that RVFV and SBV VHHs recognised different regions within the glycoprotein structure.

When they tested whether the VHHs could neutralise the virus in a test tube, they found that single VHHs could not do the job. Combining two different VHHs had a slightly better neutralising effect against SBV, but this was not effective for RVFV. To address this, they used 'superglue' derived from bacteria to stick multiple VHHs together as a single antibody complex. The resulting VHH antibody complexes efficiently neutralised both viruses, but only if the VHHs in the complex targeted more than one region of the virus glycoprotein head.

Studies in mice with the best performing VHH antibody complexes showed that these complexes were able to prevent death. The number of viruses in the blood of the treated mice was also substantially reduced compared with the untreated animals.

To work in humans optimally, antibodies need to have all the effector functions of natural human antibodies. To this end, the team constructed llama-human chimeric antibodies. Administering a promising chimeric antibody to mice before infection prevented lethal disease in 80% of the animals, and treating them with the antibody after infection prevented mortality in 60%.

"We've harnessed the beneficial characteristics of VHHs in combination with bacterial superglues to develop highly potent virus neutralising complexes," concludes senior author Jeroen Kortekaas, Senior Scientist at Wageningen Bioveterinary Research, and Professor of the Laboratory of Virology, Wageningen University, The Netherlands. "Our approach could aid the development of therapeutics for bunyaviruses and other viral infections, as well as diseases including cancer."