Tech

The psychedelic drug psilocybin, a naturally occurring compound found in some mushrooms, has been studied as a potential treatment for depression for years. But exactly how it works in the brain and how long beneficial results might last is still unclear.

In a new study, Yale researchers show that a single dose of psilocybin given to mice prompted an immediate and long-lasting increase in connections between neurons. The findings are published July 5 in the journal Neuron.

"We not only saw a 10% increase in the number of neuronal connections, but also they were on average about 10% larger, so the connections were stronger as well," said Yale's Alex Kwan, associate professor of psychiatry and of neuroscience and senior author of the paper.

Previous laboratory experiments had shown promise that psilocybin, as well as the anesthetic ketamine, can decrease depression. The new Yale research found that these compounds increase the density of dendritic spines, small protrusions found on nerve cells which aid in the transmission of information between neurons. Chronic stress and depression are known to reduce the number of these neuronal connections.

Using a laser-scanning microscope, Kwan and first author Ling-Xiao Shao, a postdoctoral associate in the Yale School of Medicine, imaged dendritic spines in high resolution and tracked them for multiple days in living mice. They found increases in the number of dendritic spines and in their size within 24 hours of administration of psilocybin. These changes were still present a month later. Also, mice subjected to stress showed behavioral improvements and increased neurotransmitter activity after being given psilocybin.

For some people, psilocybin, an active compound in "magic mushrooms," can produce a profound mystical experience. The psychedelic was a staple of religious ceremonies among indigenous populations of the New World and is also a popular recreational drug.

It may be the novel psychological effects of psilocybin itself that spurs the growth of neuronal connections, Kwan said.

"It was a real surprise to see such enduring changes from just one dose of psilocybin," he said. "These new connections may be the structural changes the brain uses to store new experiences."

A new collaborative research led by researchers from the National Institute for Environmental Studies, Potsdam Institute for Climate Impact Research, Ritsumeikan University, and Kyoto University found that although unlimited irrigation could increase global BECCS potential (via the increase of bioenergy production) by 60-71% by the end of this century, sustainably constrained irrigation would increase it by only 5-6%. The study has been published in Nature Sustainability on July 5.

Bioenergy with carbon capture and storage (BECCS) is a process of extracting bioenergy from biomass, then capturing and storing the carbon to a geological reservoir. It is a negative emission technology since the biomass is produced by plants through photosynthesis that can uptake the carbon dioxide from atmosphere. To achieve the 2°C or 1.5°C climate goal, large-scale deployment of BECCS was assumed to be prominent in many previous studies. However, this caused increasing concerns on the challenges brought to water and land resources to grow the bioenergy crops. For example, existing studies have showed that irrigation to achieve considerable bioenergy crop production needed for BECCS potential comparable to the requirement of 2°C or 1.5°C climate goal would lead to severe water stress even than climate change itself.

Under this context, where and to what extent irrigation can enhance the global BECCS potential remains unknown under sustainable water use. "Here, we define it as water use securing the local and downstream water availability for conventional water use and environmental flow requirements, suppressing nonrenewable water resources withdrawal, and preventing additional water stress." explains lead author Zhipin Ai from National institute for environmental studies, Japan.

The study was based on simulations with a spatially explicit representation of bioenergy crop plantations and water cycle in an internally consistent model framework. To quantitatively determine the constraints of irrigation water resources, the researchers designed distinct irrigation ways (unlimited irrigation, sustainable irrigation, and no irrigation) with bioenergy crops planted on land scenarios with strict land protections to prevent adverse effects on biodiversity, food production, land degradation, and desertification due to large-scale land conversion.

The study found that, under the rain fed condition, the average global BECCS potential in 2090 was 0.82-1.99 Gt C yr-1. The BECCS potential reached 1.32-3.42 Gt C yr-1 (60% and 71% increases compared to that under rainfed condition) under full irrigation, whereas under sustainable irrigation, the BECCS potential was 0.88-2.09 Gt C yr-1 (5% and 6% increases compared to that under rainfed condition). The BECCS potential under sustainable irrigation is close to the lower limit of 1.6-4.1 Gt C yr-1, which is the required amount of BECCS in 2100 that consistent with the 1.5°C or 2°C climate goal as documented in the IPCC Special Report on Global Warming of 1.5ºC.

Given the many negative environmental impacts of large-scale deployment of BECCS, the researchers suggest that comprehensive assessments of the BECCS potential that consider both potential benefits and adverse effects are necessary for simultaneously achieving the multiple sustainable development goals on climate, water, land, etc. "In addition, considering the relatively low biophysically constrained BECCS potential under sustainable water and land use scenarios, a critical reexamination of the contribution of BECCS towards achieving the Paris Agreement goal is needed." says co-author Vera Heck from the Potsdam Institute for Climate Impact Research.

Although most Canadians die from predictable causes and have health needs that can be met at home, only 20% of people receive a physician home visit in their last year of life.

To help understand the changing care needs of older adults as they age and when they might be nearing the end of their lives, a team of researchers developed the Risk Evaluation for Support: Predictions for Elder-Life in the Community Tool (RESPECT).

The calculator, which predicts death within 6 months, is based on data from more than 491 000 community-dwelling older adults who used home care in the 6-year period between 2007 and 2013.

"The RESPECT calculator allows families and their loved ones to plan," says Dr. Amy Hsu, investigator at the Bruyère Research Institute, affiliate investigator at The Ottawa Hospital, and faculty in the Department of Family Medicine at the University of Ottawa. "For example, it can help an adult child plan when to take a leave of absence from work to be with a parent or decide when to take the last family vacation together."

Using a "big data" approach that represents a population perspective of the end-of-life experience of older adults in Ontario, RESPECT provides estimates of survival. The research team found that declines in a person's ability to carry out activities of daily living, such as hygiene, using the toilet, and locomotion, were stronger predictors of 6-month mortality than the diseases that a person has.

"Knowing how long a person has to live is essential in making informed decisions about what treatments they should get and where they should get them," says Dr. Peter Tanuseputro, physician-scientist at The Ottawa Hospital and ICES, and investigator at the Bruyère Research Institute. "As a person gets closer to death, the balance shifts from having curative care as the primary goal, to care that maximizes a person's quality of remaining life."

The tool was designed with patients and their care partners in mind and has been piloted in community settings in Ontario. It can also be used by physicians and home care staff, in addition to palliative care professionals.

Inadequate exposure to UVB light from the sun may be associated with an increased risk of colorectal cancer, particularly in older age groups, according to a study using data on 186 countries, published in the open access journal BMC Public Health.

Researchers at the University of California San Diego, USA investigated possible associations between global levels of UVB light in 2017 and rates of colorectal cancer for different countries and age groups in 2018.

The authors found that lower UVB exposure was significantly correlated with higher rates of colorectal cancer across all age groups from 0 to over 75 years in people living in the 186 countries included in the study. The association between lower UVB and risk of colorectal cancer remained significant for those aged above 45 after other factors, such as skin pigmentation, life expectancy and smoking were taken into consideration. Data on these factors were available for 148 countries.

The authors suggest that lower UVB exposure may reduce levels of vitamin D. Vitamin D deficiency has previously been associated with an increased risk of colorectal cancer. Future research could look directly at the potential benefits on colorectal cancer of correcting vitamin D deficiencies, especially in older age groups, according to the authors.

Raphael Cuomo, co-author of the study said: "Differences in UVB light accounted for a large amount of the variation we saw in colorectal cancer rates, especially for people over age 45. Although this is still preliminary evidence, it may be that older individuals, in particular, may reduce their risk of colorectal cancer by correcting deficiencies in vitamin D."

The authors used UVB estimates obtained by the NASA EOS Aura spacecraft in April 2017 and data on colorectal cancer rates in 2018 for 186 countries from the Global Cancer (GLOBOCAN) database. They also collected data for 148 countries on skin pigmentation, life expectancy, smoking, stratospheric ozone (a naturally-occurring gas that filters the sun's radiation) and other factors which may influence health and UVB exposure from previous literature and databases. Countries with lower UVB included Norway, Denmark and Canada, while countries with higher UVB included United Arab Emirates, Sudan, Nigeria, and India.

The authors caution that other factors may affect UVB exposure and vitamin D levels, such as vitamin D supplements, clothing and air pollution, which were not included in the study. They also caution that the observational nature of the study does not allow for conclusions about cause and effect and more work is needed to understand the relationship between UVB and vitamin D with colorectal cancer in more detail.

Why are gold deposits found at all? Gold is famously unreactive, and there seems to be little reason why gold should be concentrated, rather than uniformly scattered throughout the Earth's crust. Now an international group of geochemists have discovered why gold is concentrated alongside arsenic, explaining the formation of most gold deposits. This may also explain why many gold miners and others have been at risk from arsenic poisoning. This work is presented at the Goldschmidt conference, after recent publication*.

Gold has been prized for millennia, for its purity and stability. It's also rare enough to retain its value - the World Gold Council estimates that all the gold ever mined in the world would fit into a 20x20x20-meter cube. It is valued for its beauty, but also because it is one of the most inert metals in the whole Periodic Table, it doesn't easily react with other substances. So why should gold come together in sufficient quantity to mine - why are there gold deposits at all?

Some gold is found as gold nuggets, the stuff of prospectors' dreams, but an appreciable amount is bound up with minerals. Gold is known to be related to iron- and arsenic-containing minerals, such as pyrite and arsenopyrite. These minerals act sort of like a sponge, and are capable of concentrating gold up to a million times more than is found elsewhere in nature, such as in the hot spring waters that transport the gold. This gold becomes chemically bound in these minerals, so it is invisible to the naked eye.

The scientific team studied the action of the gold-concentrating minerals using the intense X-rays beam produced by the European Synchrotron (ESRF) at Grenoble in France, which can probe the chemical bonds between the mineral and gold.

They found that when the mineral is enriched with arsenic, gold can enter the mineral structural sites by directly binding to arsenic (forming, chemically speaking, Au(2+) and As(1-) bonds), which allows gold to be stabilised in the mineral. However, when the arsenic concentration is low, gold doesn't enter the mineral structure but only forms weak gold-sulfur bonds with the mineral surface.

Lead researcher, Dr. Gleb Pokrovski, Directeur de Recherche at CNRS, GET-CNRS-University of Toulouse Paul Sabatier said:

"Our results show that arsenic drives the concentration of gold. This arsenic-driven gold pump explains how these iron sulfides can massively capture and then release gold, so controlling ore deposit formation and distribution. In practical terms, it means that it will make it easier to find new sources of gold and other precious metals, which bind to arsenic-containing iron sulfides. It may also open the door to controlling the chemical reactions, and if we can improve gold processing, we can recover more gold".

The new model identifies just why gold tends to be found with arsenic. Dr Pokrovski continued:

"It has been known for centuries that gold is found with arsenic, and this has caused severe health problems for gold miners. Now we know what happens at an atomic level, we can begin to see if there's anything we can do to prevent this".

The noxious link between arsenic and gold is well-known in France and elsewhere in the world, including at the Salsigne mine near Carcassonne. This was one of Western Europe's largest gold mines, and the world's largest arsenic producer at one time. It closed in 2004, but the environmental consequences of the arsenic pollution still persist in the region.

Dr. Jeffrey Hedenquist, University of Ottawa, commented that "Geologists as well as prospectors have long known that gold can be associated with arsenic-rich minerals, and over the past few decades others have quantified this association. The findings of Dr. Pokrovski and his team now help to explain why we see this association, caused by an atomic-scale attraction between gold and arsenic, with this marriage arranged by the structure of certain minerals."

Scientists have reconstructed the Eastern Mediterranean silver trade, over a period including the traditional dates of the Trojan War, the founding of Rome, and the destruction of Solomon's Temple in Jerusalem. The team of French, Israeli and Australian scientists and numismatists found geochemical evidence for pre-coinage silver trade continuing throughout the Mediterranean during the Late Bronze and Iron Age periods, with the supply slowing only occasionally. Silver was sourced from the whole north-eastern Mediterranean, and as far away as the Iberian Peninsula.

The team used high-precision isotopic analysis to identify the ore sources of minute lead traces found in silver Hacksilber. Hacksilber is irregularly cut silver bullion including broken pieces of silver ingots and jewellery that served as means of payment in the southern Levant from the beginning of the second millennium until the fourth century BCE. Used in local and international transactions, its value was determined by weighing it on scales against standardized weights. It has been discovered in archaeological excavations in the region usually stored inside ceramic containers and it had to be imported as there was no silver to be mined in the Levant.

Presenting the research at the Goldschmidt geochemistry conference, Dr. Liesel Gentelli said "Even before coinage there was international trade, and Hacksilber was one of the commodities being exchanged for goods".

The team analysed Hacksilber from 13 different sites dating from 1300 BCE to 586 BCE in the southern Levant, modern-day Israel and the Palestinian Authority. The samples included finds from 'En Gedi, Ekron, and Megiddo (also known as Armageddon). They matched their findings with ore samples, and have shown that most of the Hacksilber came from the Southern Aegean and Balkans (Macedonia, Thrace and Illyria). Some was also found to come from as far away as Sardinia and Spain.

Lead researcher Liesel Gentelli (École normale supérieure de Lyon, France) said:

"Previous researchers believed that silver trade had come to an end following the societal collapse at the end of the Late Bronze Age, but our research shows that exchanges between especially the southern Levant and the Aegean world never came to a stop. People around the Eastern Mediterranean remained connected. It's likely that the silver flowed to the Levant as a result of trade or plunder.

We do see periods of silver scarcity around the time of the Bronze to Iron Age transition, around 1300-1100 BCE. Some hoards from this period show the silver displaying unusually high copper content, which would have been added to make up for the lack of silver.

We can't match our findings on the silver trade to specific historical events, but our analysis shows the importance of Hacksilber trade from before the Trojan War, which some scholars date to the early 12th century BCE, through the founding of Rome in 753 BCE, and up to the end of the Iron Age in 586 BCE, marked by Nebuchadnezzar's destruction of Solomon's Temple in Jerusalem. After that, we see the gradual introduction of coinage, first as finds of several archaic coins and later a transition to a monetary economy in the southern Levant circa 450 BCE which made the trade of Hacksilber less relevant. However, this work reveals the ongoing and crucial economic role that Hacksilber played in the Bronze and Iron Ages economies".

Commenting, Dr Matthew Ponting, Senior Lecturer in Archaeological Materials at the University of Liverpool said:

"This is important new work that confirms our understanding of trade and exchange routes in the Early Iron Age Levant. The fact that all silver found in the region would have had to have been imported presents exciting possibilities to investigate trade routes more generally as well as to learn more about alloy use and preference during this important period of history".

Tokyo, Japan - Researchers from Tokyo Metropolitan University have used high power impulse magnetron scattering (HiPIMS) to create thin films of tungsten with unprecedentedly low levels of film stress. By optimizing the timing of a "substrate bias pulse" with microsecond precision, they minimized impurities and defects to form crystalline films with stresses as low as 0.03 GPa, similar to those achieved through annealing. Their work promises efficient pathways for creating metallic films for the electronics industry.

Modern electronics relies on the intricate, nanoscale deposition of thin metallic films onto surfaces. This is easier said than done; unless done right, "film stresses" arising from the microscopic internal structure of the film can cause buckling and curving over time. Getting rid of these stresses usually requires heating or "annealing". Unfortunately, many of the best metals for the job e.g. tungsten have high melting points, meaning that the film needs to be heated to over 1000 degrees Celsius. Not only is this energy intensive, but it severely limits which substrate materials can be used. The race is on to create films out of high melting point metals without these stresses in the first place.

A team led by Associate Professor Tetsuhide Shimizu of Tokyo Metropolitan University have been working with a technique known as high power impulse magnetron scattering (HiPIMS), a sputtering technique. Sputtering involves applying a high voltage across a metallic "target" and a substrate, creating a plasma of charged gas atoms which bombards the metallic target and forms a charged metal vapor; these metal ions fly towards the substrate where they form a film. In the case of HiPIMS, the voltage is pulsed in short, powerful bursts. After each pulse, it is known that there is some separation between the arrival of metal and gas ions at the substrate; a synchronized "substrate bias" pulse can help selectively accelerate the metal ions, creating denser films. Yet despite many efforts, the issue of residual stress remained.

Now, using argon gas and a tungsten target, the team looked at how ions with different energies arrived at the substrate over time in unprecedented detail. Instead of using a bias pulse set off at the same time as the HiPIMS pulse, they used their knowledge of when different ions arrived and introduced a tiny delay, 60 microseconds, to precisely select for the arrival of high energy metal ions. They found that this minimized the amount of gas ending up in the film and efficiently delivered high levels of kinetic energy. The result was a dense crystalline film with large grains and low film stress. By making the bias stronger, the films became more and more stress-free. The efficient delivery of energy to the film meant that they had, in fact, achieved a similar effect to annealing while they deposited the film. By further swapping out argon for krypton, the team realized films with a stress as low as 0.03 GPa, comparable to what can be made with post-annealing.

An efficient pathway to stress-free films will have a significant impact on metallization processes and the manufacture of next-generation circuitry. The technology may be applied to other metals and promises big gains for the electronics industry.

In recent years, immunotherapy has revolutionised the field of cancer treatment. However, inflammatory reactions in healthy tissues frequently trigger side effects that can be serious and lead to the permanent discontinuation of treatment. This toxicity is still poorly understood and is a major obstacle to the use of immunotherapy. Scientists from the University of Geneva (UNIGE), Switzerland, and Harvard Medical School, United States, have succeeded in establishing the differences between deleterious immune reactions and those targeting tumour cells that are sought after. It appears that while the immune mechanisms are similar, the cell populations involved are different. This work, published in the journal Science Immunology, makes it possible to envisage better targeted, more effective, and less dangerous treatments for cancer patients.

Based on massive stimulation of the patient's immune system, immunotherapies have saved many lives. Unfortunately, they are not without consequences. "When the immune system is activated so intensively, the resulting inflammatory reaction can have harmful effects and sometimes cause significant damage to healthy tissue", says Mikaël Pittet, holder of the ISREC Foundation Chair in Onco-Immunology at UNIGE Faculty of Medicine Department of Pathology and Immunology and Centre for Translational Research in Onco-Haematology, and a member of the Swiss Cancer Centre Leman. "Therefore, we wanted to know if there are differences between a desired immune response, which aims to eliminate cancer, and an unwanted response, which can affect healthy tissue. The identification of distinctive elements between these two immune reactions would indeed allow the development of new, more effective and less toxic therapeutic approaches."

Using liver biopsy samples from patients treated at the CHUV and the HUG who had suffered such toxic reactions, the scientists studied the cellular and molecular mechanisms at work to reveal similarities and dissimilarities.

A similar response, but with different cells

In an immunotherapy-related toxic response, two types of immune cells -- macrophage and neutrophil populations -- appear to be responsible for attacking healthy tissue, but are not involved in killing cancer cells. In contrast, another cell type -- a population of dendritic cells -- is not involved in attacking healthy tissue but is essential for eliminating cancer cells. "Immunotherapies can trigger the production of specialised proteins that alert the immune system and trigger an inflammatory response, explains Mikaël Pittet. In a tumour, these proteins are welcome because they allow the immune system to destroy cancerous cells. In healthy tissue, however, the presence of these same proteins can lead to the destruction of healthy cells. The fact that these inflammatory proteins are produced by such different cells in tumours and healthy tissue is therefore an interesting finding."

Dendritic cells are very rare, whereas macrophages and neutrophils are much more common. Some macrophages are present in most of our organs from embryonic development stages and remain there throughout our lives. Contrary to what was previously thought, these macrophages do not necessarily inhibit inflammation but, stimulated by immunotherapies, can trigger a harmful inflammatory response in the healthy tissue where they reside, thus explaining why toxicity can affect different organs.

Neutralising neutrophils for a double benefit

When macrophages are activated by drugs, they produce inflammatory proteins. These in turn activate neutrophils, which execute the toxic reaction. "This opens the possibility of limiting immunotherapy's side effects by manipulating neutrophils", says Mikaël Pittet.

The research team confirmed their discovery by studying the immune reactions of mice whose cell activity was modulated with genetic tools. They were able to identify a loophole that could be exploited to eliminate these side effects. Indeed, neutrophils produce some factors that are important for the development of toxicity, including TNF-α, which could be a therapeutic target. TNF-α inhibitors are already used to modulate the immune response in people with arthritis and could perhaps be useful in the cancer setting to inhibit the toxic effects of neutrophils during immunotherapy. "Furthermore, inhibiting neutrophils could be a more effective way to fight cancer: in addition to triggering a toxic response, some of these cells also promote tumour growth. Thus, by managing to control them, we could have a double beneficial effect: overcome the toxicity in healthy tissues, and limit the growth of cancerous cells", concludes Mikaël Pittet.

BUFFALO, N.Y. -- A year after University at Buffalo scientists demonstrated that it was possible to produce millions of mature human cells in a mouse embryo, they have published a detailed description of the method so that other laboratories can do it, too.

The ability to produce millions of mature human cells in a living organism, called a chimera, which contains the cells of two species, is critical if the ultimate promise of stem cells to treat or cure human disease is to be realized. But to produce those mature cells, human primed stem cells must be converted back into an earlier, less developed naive state so that the human stem cells can co-develop with the inner cell mass in a mouse blastocyst.

The protocol outlining how to do that has now been published in Nature Protocols by the UB scientists. They were invited to publish it because of the significant interest generated by the team's initial publication describing their breakthrough last May.

"This paper will enable many scientists to use this new platform to study the human disease of their interest," said Jian Feng, PhD, professor of physiology and biophysics in the Jacobs School of Medicine and Biomedical Sciences at UB and senior author. "Over time, it will transform biomedical research toward a more effective use of the human model system to directly study virtually any inborn condition of an individual. It will stimulate unforeseen discoveries and applications that may fundamentally change our understanding of human biology and medicine."

The protocol will allow scientists to create animal models that Feng said provide a much more realistic picture of embryonic development than has ever been possible. These more realistic animal models also will have the potential to reveal the mechaniswms behind numerous diseases, especially those that afflict individuals from birth.

Better mouse models

"This step-by-step protocol will benefit the entire field by enabling other scientists to use our methods to generate chimeras to study human diseases that they are experts in," said Feng. "It will lead to the generation of better mouse models for various human diseases, such as sickle cell anemia, COVID-19 and many others, or various human developmental disorders."
The paper demonstrates how to generate naive human pluripotent stem cells from existing induced pluripotent stem cells that may be derived from patients with various diseases, how to generate mouse-human chimeras using these cells and how to quantify the amount of human cells in the chimeras.

"Using our method, one can now track the development of naive human pluripotent stem cells in mouse-human chimeric embryos in real-time," said Feng. These stem cells can then be manipulated either genetically or pharmacologically, providing valuable information about human development and disease.

"For example, one can label naive human pluripotent stem cells by inserting green fluorescent protein in a hemoglobin gene to study the development of human red blood cells in mouse-human chimeras," said Feng.

Another application is to generate humanized mouse models to study many human diseases.

"These mice contain critical human cells, tissues or even organs so that they more accurately reflect the human condition," said Feng. "With our method, the human cells are made along with the mouse during the development of the mouse embryo. There would be better matching and no rejections, because there are ways for the human cells to be made where there is no competition from their mouse counterparts."

Organs for transplant in the future

By allowing others to improve and adapt the method to eventually generate chimeras in larger animals, this protocol may also lead to the generation of human organs to address the dire shortage of organs available for transplant, said Feng.

"If naive human pluripotent stem cells are able to generate significant amounts of mature human cells in other larger species, it could be possible to make human tissues or even human organs in chimeric animals," Feng explained.

This would be possible using blastocyst complementation where, Feng explained, normal pluripotent stem cells from one species can reconstitute an organ for that species in a blastocyst of another species that been genetically modified not to grow that particular organ.

Feng added: "Ultimately, a better understanding of how human cells develop and grow in chimeras may enable the generation of human cells, tissues and organs in a completely artificial system and fundamentally change how we treat many human diseases. Research using chimeras is a bridge that must be crossed to reach that possibility."

There are plenty of negatives associated with smart technology -- tech neck, texting and driving, blue light rays -- but there is also a positive: the digital age is not making us stupid, says University of Cincinnati social/behavioral expert Anthony Chemero.

"Despite the headlines, there is no scientific evidence that shows that smartphones and digital technology harm our biological cognitive abilities," says the UC professor of philosophy and psychology who recently co-authored a paper stating such in Nature Human Behaviour.

In the paper, Chemero and colleagues at the University of Toronto's Rotman School of Management expound on the evolution of the digital age, explaining how smart technology supplements thinking, thus helping us to excel.

"What smartphones and digital technology seem to do instead is to change the ways in which we engage our biological cognitive abilities," Chemero says, adding "these changes are actually cognitively beneficial."

For example, he says, your smart phone knows the way to the baseball stadium so that you don't have to dig out a map or ask for directions, which frees up brain energy to think about something else. The same holds true in a professional setting: "We're not solving complex mathematical problems with pen and paper or memorizing phone numbers in 2021."

Computers, tablets and smart phones, he says, function as an auxiliary, serving as tools which are good at memorization, calculation and storing information and presenting information when you need it.

Additionally, smart technology augments decision making skills that we would be hard pressed to accomplish on our own, says the paper's lead author Lorenzo Cecutti, a PhD candidate at the University of Toronto. Using GPS technology on our phones, he says, can not only help us get there, but lets us choose a route based on traffic conditions. "That would be a challenging task when driving round in a new city."

Chemero adds: "You put all this technology) together with a naked human brain and you get something that's smarter...and the result is that we, supplemented by our technology, are actually capable of accomplishing much more complex tasks than we could with our un-supplemented biological abilities."

While there may be other consequences to smart technology, "making us stupid is not one of them," says Chemero.

When environmental physicist Kira Rehfeld, from Heidelberg University, visited Antarctica for her research, she was struck by the intense light there. "It's always light in summer. This solar radiation could actually be used to supply the research infrastructure with energy", she observes. However, generators, engines, and heaters in these remote regions have mostly been powered until now by fossil fuels delivered by ship, such as petroleum or petrol, which cause global warming. Besides the high associated economic costs, pollution from even the smallest spills is also a major problem threatening the especially sensitive ecosystem.

Fossil fuels could be replaced by hydrogen, though, a versatile energy medium that in addition is able to be stored extremely well at low temperatures. "Our idea was therefore to use solar modules to produce climate-neutral hydrogen on site during the Antarctic summer by splitting water into hydrogen and oxygen through electrolysis", says May, then a postdoc at the Helmholtz-Zentrum Berlin Institute for Solar Fuels. Rehfeld and May applied for funding from the Volkswagen Foundation to investigate whether hydrogen can be generated using sunlight even at sub-zero temperatures, and which method is best suited for this. Low temperatures can considerably reduce the efficiency of electrolysis, though cold actually increases the efficiency of most solar modules.

May and his HZB colleague, Moritz Kölbach, have now empirically compared two different approaches: a conventional setup in which the photovoltaic module is thermally and physically separated from the electrolysis tank, and a newer, thermally coupled setup in which the photovoltaic module is in close contact with the wall of the electrolysis tank, promoting thermal diffusion. To simulate Antarctic conditions, Kölbach obtained a freezer, cut a hole in the door, installed a quartz window, and illuminated the inside of the cabinet with simulated sunlight. He filled the electrolysis container with 30 per cent sulphuric acid (also known as battery acid) that has a freezing point around -35 degrees Celsius and conducts electricity well.

Kölbach then set up the experimental cells, and carried out the series of measurements. During operation, it became apparent that the cell with the thermally coupled PV modules produced comparatively more hydrogen, since the illuminated PV modules pass their waste heat directly to the electrolyser. "We were even able to increase the efficiency by adding additional thermal insulation to the electrolyser. As a result, the electrolyte temperature climbed during illumination from -20 to as high as +13.5 degrees Celsius", says Kölbach.

The results of this study confirm that thermally coupled systems have potentially higher efficiency than thermally decoupled ones. Whether these advantages can be exploited economically, however, remains to be seen. "Therefore, in the next phase we want to test prototypes under realistic conditions. That will certainly be exciting and we are currently looking for partners for this", says May.

Locally generated solar hydrogen could be an option for replacing fossil fuels and eliminating the associated pollution danger to the environment and CO2 emissions, not only at the South Pole, but also in other extremely cold and sparsely populated regions of the world. This could include the high Alps, Canada and Alaska, the Andes, and other mountainous regions like the Himalayas.

"Perhaps solar-generated hydrogen will be economically viable initially in these kinds of remote regions of the world", says May, recalling the triumphant advance of photovoltaics, which first began supplying power to satellites in space about 60 years ago.

MANHATTAN, KANSAS -- Research led by Kansas State University's Suprem Das, assistant professor of industrial and manufacturing systems engineering, in collaboration with Christopher Sorensen, university distinguished professor of physics, shows potential ways to manufacture graphene-based nano-inks for additive manufacturing of supercapacitors in the form of flexible and printable electronics.

As researchers around the world study the potential replacement of batteries by supercapacitors, an energy device that can charge and discharge very fast -- within few tens of seconds -- the team led by Das has an alternate prediction. The team's work could be adapted to integrate them to overcome the slow-charging processes of batteries. Furthermore, Das has been developing additive manufacturing of small supercapacitors -- called micro-supercapacitors -- so that one day they could be used for wafer-scale integration in silicon processing.

"Additive manufacturing is fascinating, cost-effective and has versatile design considerations," Das said.

The team has developed supercapacitors that have been tested for 10,000 cycles of charging and discharging cycles, a number that is promising to evaluate the reliability of these devices, Das said The team is also studying the versatility of these micro-supercapacitors by printing on mechanically flexible surfaces. For this, they used 20-micrometer-hin polyimide -- plastic -- substrates with high reliability. Das is highly interested in translating emerging materials to devices.

"When you think about best materials and wish to make the best devices, it is not simple and straightforward," Das said. "One needs to then understand the underpinning physics and chemistry involved in devices."

Another advantage of Das' invention is the green aspects of the research that he visualized through constructive discussions with Sorensen. When Das met Sorensen, he realized he could use his expertise in additive manufacturing to transform these materials into useful things; in this case, making tiny energy storage devices.

A few months later, Das filed for a U.S. patent after developing a nano-ink technology and used it to demonstrate printed micro-supercapacitors.

Das is particularly interested in forming this synergistic collaboration with Sorensen because of the energy-efficient, highly scalable and chemical-free nature of the graphene production process and his own group's graphene ink manufacturing process. Both of these processes are patented/patent-pending technologies and are industrially relevant, Das said.

"We make high-quality, multilayer graphene by detonating fuel-rich mixtures of unsaturated hydrocarbons such as acetylene with oxygen in a multi-liter chamber," Sorensen said. "Our patented method is simple requires very little energy, hence is ecologically benign; requires no toxic chemicals; and has been scaled up to yield high-quality, inexpensive graphene."

Graphene has been recognized as a wonder material with much potential because of its many superlative physical properties Many graphene manufacturing methods have been developed across the globe and graphene has been produced in ton quantities. Technologists, however, are well aware that graphene is not yet in the marketplace because none of these methods have had the right combination of economy, ecology and product quality to allow graphene to fulfill its potential. But both the methods of producing graphene and nano-inks pursued at Kansas State University are on target to address all of these requirements, according to Sorensen and Das.

How on Earth?

It has puzzled scientists for years whether and how bacteria, that live from dissolved organic matter in marine waters, can carry out N2 fixation. It was assumed that the high levels of oxygen combined with the low amount of dissolved organic matter in the marine water column would prevent the anaerobic and energy consuming N2 fixation.

Already in the 1980s it was suggested that aggregates, so-called "marine snow particles", could possibly be suitable sites for N2 fixation, but this was never proven.

Until now..

In a new study, researchers from the University of Copenhagen demonstrate, by use of mathematical models, that microbial fixation of nitrogen can take place on these aggregates of live and dead organisms in the marine plankton. The study has just been published in the prestigious Nature Communications.

Marine snow

Marine snow consists of debris from diverse organisms in the water column.

Picture shows marine snow from the Sargasso Sea. Photo: L. Riemann

-- "Our work took almost two years, but it was definitely worth the effort, since the results are quite a breakthrough. In close collaboration with our research collaborators at the Center for Ocean Life at DTU Aqua and in the USA, we managed to create a model mimicking conditions on marine snow particles. With this model, we show that a marine particle can become densely colonized by bacteria. This growth of bacteria causes extensive respiration leading to low oxygen concentrations on the particle, which ultimately allows for the anaerobic process of N2 fixation", explains first-author and postdoc at the Department of Biology, University of Copenhagen, Subhendu Chakraborty.

With their model the researchers could also show the depth distribution of N2 fixation in the marine water column. They found, that among other things, the N2 fixation is dependent on the size, density and sinking speed of the marine snow particles. Moreover, they demonstrated that their modelled rates were comparable to actual rates measured in marine waters.

Marine water sampler

Marine water samples are often taken with bottles attached to a so-called rosette, as seen here. Photo: L.asse Riemann

-- "This comparison gave us confidence in the model", says corresponding author Lasse Riemann, Professor at the Department of Biology. He continues: "We are very proud of our study, because it provides the first explanation of how marine-snow-associated N2 fixation can take place. Furthermore, the results indicate that this process is important for the global marine nitrogen cycling and thereby for plankton growth and productivity".

The researchers hope their study will inspire future work on microbial life on marine particles, due to its seemingly pivotal role in the cycling of many nutrients in the ocean.

Berkeley -- Many insects and spiders get their uncanny ability to scurry up walls and walk upside down on ceilings with the help of specialized sticky footpads that allow them to adhere to surfaces in places where no human would dare to go.

Engineers at the University of California, Berkeley, have used the principle behind some of these footpads, called electrostatic adhesion, to create an insect-scale robot that can swerve and pivot with the agility of a cheetah, giving it the ability to traverse complex terrain and quickly avoid unexpected obstacles.

The robot is constructed from a thin, layered material that bends and contracts when an electric voltage is applied. In a 2019 paper, the research team demonstrated that this simple design can be used to create a cockroach-sized robot that can scurry across a flat surface at a rate of 20 body lengths per second, or about 1.5 miles per hour -- nearly the speed of living cockroaches themselves, and the fastest relative speed of any insect-sized robot.

In a new study, the research team added two electrostatic footpads to the robot. Applying a voltage to either of the footpads increases the electrostatic force between the footpad and a surface, making that footpad stick more firmly to the surface and forcing the rest of the robot to rotate around the foot.

The two footpads give operators full control over the trajectory of the robot, and allow the robot to make turns with a centripetal acceleration that exceeds that of most insects.

"Our original robot could move very, very fast, but we could not really control whether the robot went left or right, and a lot of the time it would move randomly, because if there was a slight difference in the manufacturing process -- if the robot was not symmetrical - it would veer to one side," said Liwei Lin, a professor of mechanical engineering at UC Berkeley. "In this work, the major innovation was adding these footpads that allow it to make very, very fast turns."

To demonstrate the robot's agility, the research team filmed the robot navigating Lego mazes while carrying a small gas sensor and swerving to avoid falling debris. Because of its simple design, the robot can also survive being stepped on by a 120-pound human.

Small, robust robots like these could be ideal for conducting search and rescue operations or investigating other hazardous situations, such as scoping out potential gas leaks, Lin said. While the team demonstrated most of the robot's skills while it was "tethered," or powered and controlled through a small electrical wire, they also created an "untethered" version that can operate on battery power for up to 19 minutes and 31 meters while carrying a gas sensor.

"One of the biggest challenges today is making smaller scale robots that maintain the power and control of bigger robots," Lin said. "With larger-scale robots, you can include a big battery and a control system, no problem. But when you try to shrink everything down to a smaller and smaller scale, the weight of those elements become difficult for the robot to carry and the robot generally moves very slowly. Our robot is very fast, quite strong, and requires very little power, allowing it to carry sensors and electronics while also carrying a battery."

Berkeley -- Many insects and spiders get their uncanny ability to scurry up walls and walk upside down on ceilings with the help of specialized sticky footpads that allow them to adhere to surfaces in places where no human would dare to go.

Engineers at the University of California, Berkeley, have used the principle behind some of these footpads, called electrostatic adhesion, to create an insect-scale robot that can swerve and pivot with the agility of a cheetah, giving it the ability to traverse complex terrain and quickly avoid unexpected obstacles.

The robot is constructed from a thin, layered material that bends and contracts when an electric voltage is applied. In a 2019 paper, the research team demonstrated that this simple design can be used to create a cockroach-sized robot that can scurry across a flat surface at a rate of 20 body lengths per second, or about 1.5 miles per hour -- nearly the speed of living cockroaches themselves, and the fastest relative speed of any insect-sized robot.

In a new study, the research team added two electrostatic footpads to the robot. Applying a voltage to either of the footpads increases the electrostatic force between the footpad and a surface, making that footpad stick more firmly to the surface and forcing the rest of the robot to rotate around the foot.

The two footpads give operators full control over the trajectory of the robot, and allow the robot to make turns with a centripetal acceleration that exceeds that of most insects.

"Our original robot could move very, very fast, but we could not really control whether the robot went left or right, and a lot of the time it would move randomly, because if there was a slight difference in the manufacturing process -- if the robot was not symmetrical - it would veer to one side," said Liwei Lin, a professor of mechanical engineering at UC Berkeley. "In this work, the major innovation was adding these footpads that allow it to make very, very fast turns."

To demonstrate the robot's agility, the research team filmed the robot navigating Lego mazes while carrying a small gas sensor and swerving to avoid falling debris. Because of its simple design, the robot can also survive being stepped on by a 120-pound human.

Small, robust robots like these could be ideal for conducting search and rescue operations or investigating other hazardous situations, such as scoping out potential gas leaks, Lin said. While the team demonstrated most of the robot's skills while it was "tethered," or powered and controlled through a small electrical wire, they also created an "untethered" version that can operate on battery power for up to 19 minutes and 31 meters while carrying a gas sensor.

"One of the biggest challenges today is making smaller scale robots that maintain the power and control of bigger robots," Lin said. "With larger-scale robots, you can include a big battery and a control system, no problem. But when you try to shrink everything down to a smaller and smaller scale, the weight of those elements become difficult for the robot to carry and the robot generally moves very slowly. Our robot is very fast, quite strong, and requires very little power, allowing it to carry sensors and electronics while also carrying a battery."