Since spring 2020, researchers at Danderyd Hospital and Karolinska Institutet have conducted the so-called COMMUNITY study, with the main purpose of examining immunity after COVID-19. In the first phase of the study in spring 2020, blood samples were collected from 2,149 employees at Danderyd Hospital, of whom about 19 percent had antibodies against SARS-CoV-2. Blood samples have since then been collected every four months, and study participants have responded to questionnaires regarding long-term symptoms and their impact on the quality of life.

In the third follow-up in January 2021, the research team examined self-reported presence of long-term symptoms and their impact on work, social and home life for participants who had had mild COVID-19 at least eight months earlier. This group consisted of 323 healthcare workers (83 percent women, median age 43 years) and was compared with 1,072 healthcare workers (86 percent women, median age 47 years) who did not have COVID-19 throughout the study period.

The results show that 26 percent of those who had COVID-19 previously, compared to 9 percent in the control group, had at least one moderate to severe symptom that lasted more than two months and that 11 percent, compared to 2 percent in the control group, had a minimum of one symptom with negative impact on work, social or home life that lasted at least eight months. The most common long-term symptoms were loss of smell and taste, fatigue, and respiratory problems.

“We investigated the presence of long-term symptoms after mild COVID-19 in a relatively young and healthy group of working individuals, and we found that the predominant long-term symptoms are loss of smell and taste. Fatigue and respiratory problems are also more common among participants who have had COVID-19 but do not occur to the same extent,” says Charlotte Thålin, specialist physician, Ph.D. and lead researcher for the COMMUNITY study at Danderyd Hospital and Karolinska Institutet. “However, we do not see an increased prevalence of cognitive symptoms such as brain fatigue, memory and concentration problems or physical disorders such as muscle and joint pain, heart palpitations or long-term fever.”

“Despite the fact that the study participants had a mild COVID-19 infection, a relatively large proportion report long-term symptoms with an impact on quality of life. In light of this, we believe that young and healthy individuals, as well as other groups in society, should have great respect for the virus that seems to be able to significantly impair quality of life, even for a long time after the infection,” says Sebastian Havervall, deputy chief physician at Danderyd Hospital and PhD student in the project at Karolinska Institutet.

The COMMUNITY study will now continue, with the next follow-up taking place in May when a large proportion of study participants are expected to be vaccinated. In addition to monitoring immunity and the occurrence of re-infection, several projects regarding post- COVID are planned.

“We will, among other things, be studying COVID-19-associated loss of smell and taste more closely, and investigate whether the immune system, including autoimmunity, plays a role in post-COVID,” says Charlotte Thålin.

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Like many scientists, they may have also wondered why this iconic arid grass grows in striking ring shapes.

Previous studies have tested whether spinifex rings could be caused by termites, water availability or nutrient depletion, but none has provided a convincing explanation.

Now scientists from UNSW Sydney have found that pathogenic soil microbes play a role in how the spinifex got its hole.

Their study, the first of its kind in an arid ecosystem, has been published in the Australian Journal of Botany.

Professor Angela Moles and Neil Ross from The Evolution & Ecology Research Centre tested the idea that an accumulation of pathogenic soil microbes might impede seedling emergence and subsequent growth in the centre of spinifex rings.

They collected soil from inside and outside naturally occurring spinifex rings and compared plants grown in soil with live microbes to plants grown in sterilised soil.

“Consistent with our hypothesis, we found that sterilising soil from the inside of spinifex rings significantly increased spinifex seedling emergence,” Prof. Moles said.

“We also found that seedings had significantly higher seedling emergence in unsterilised soil from outside the rings than in unsterilised soil from inside the rings.”

Their results suggest that die-back in the centre of spinifex plants might be explained by older parts of the plant succumbing to a build-up of pathogenic soil microbes through time, where as new seedlings tend to establish more at the outside edge of the rings where there are fewer pathogens in the soil.

“Most people tend to think of the beneficial effects of microbes on plant growth,” co-author and director of UNSW Science’s Evolution & Ecology Research Centre, Professor Angela Moles said.

“However, sterilising soil actually makes most plants grow better. That is, the negative effects of the pathogenic microbes tend to outweigh the positive effects of the beneficial microbes.”

“Overall, these results suggest that soil pathogens are quietly shaping the way the plants around us grow.”

Prof. Moles said this new information helps scientists further understand the unique ecology of Australia’s arid grasslands, and adds to the growing recognition of the crucial function that soil microbes play in terrestrial ecosystem processes worldwide.

The scientists have recommended further study to identify the types of soil microbes involved in the establishment of arid-zone plants, as well as the different types of microbes that are most important for seedlings at different times or under different germination conditions.

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Elderly people suffering from low back pain tend to have poorly performing proprioceptors, which is thought to affect their “proprioceptive control strategy” — a postural control strategy in response to vibratory stimulations as proprioceptive input. Interestingly, studies have suggested that a local vibratory stimulation can, in fact, improve proprioceptive function. In previous studies by other researchers, however, its effect on postural control is still unclear. Moreover, the studies make no distinction between poor and healthy proprioceptors and do not take into account the fact that each proprioceptor has a natural vibration response frequency.

To address these issues, a team of researchers from Japan recently conducted a study in which they explored the effect of local vibratory stimulations on the proprioceptive control strategy when applied to a poor proprioceptor. Prof. Yoshifumi Morita from Nagoya Institute of Technology, Japan, who was part of the study, published in Electronics, lays down the research question: “For elderly people with low back pain, can proprioceptive function be improved? Will it cure the low back pain?”

Researchers carried out their study over a period of 3 months in which they recruited six elderly individuals, all of whom were patients with low back pain. Researchers made each participant stand on a balance board to assess their standing balance and attached fasteners with vibrators to their legs as well as both sides of their trunk. They then generated vibration signals using a PC and amplified and output them from the vibrators as mechanical vibratory stimulations. Furthermore, they allowed the frequency of stimulation to vary with time, from an initial 20 Hz (cycles/second) up to 300 Hz, to gauge the postural response as a function of the applied frequency. Finally, they compared the proprioceptive control strategy in each patient before and after applying the stimulations to an impaired proprioceptor.

Three patients showed an improvement in their proprioceptive control strategy after their impaired muscle spindles (proprioceptor detecting stretch in muscles) responded to higher frequency, an observation that suggested that low back pain could be alleviated in patients by activating impaired proprioceptors with vibratory stimulations. Furthermore, the treatment device and protocol could be used for multiple frequency ranges, allowing for the diagnosis as well as activation of a poor proprioceptor.

Given the results, the researchers look forward to conducting a clinical trial for a larger group of patients. “The clinical trial is scheduled to start in April this year and will be conducted for the next three years. We plan to verify whether the improved proprioceptive sensation can be maintained for a long time, thus relieving elderly people of low back pain,” comments an excited Prof. Morita.

The team hopes that the trial’s findings will soon lead to the commercialization of their device, which will allow elderly patients with low back pain to finally breathe a huge sigh of relief!

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Made of sunflower pollen, the sponge is hydrophobic — it repels water — thanks to a coat of natural fatty acid on the sponge. In lab experiments, the scientists showed the sponge’s ability to absorb oil contaminants of various densities, such as gasoline and motor oil, at a rate comparable to that of commercial oil absorbents.

Oil spills are difficult to clean up, and result in severe long-lasting damage to the marine ecosystem. Conventional clean-up methods, including using chemical dispersants to break oil down into very small droplets, or absorbing it with expensive, unrecyclable materials, may worsen the damage.

So far, the researchers have engineered sponges that measure 5 cm in diameter. The research team, made up of scientists from NTU Singapore and Sungkyunkwan University in South Korea, believes that these sponges, when scaled up, could be an eco-friendly alternative to tackle marine oil spills.

Professor Cho Nam-Joon from the NTU School of Materials Science and Engineering, who led the study, said: “By finetuning the material properties of pollen, our team successfully developed a sponge that can selectively target oil in contaminated water sources and absorb it. Using a material that is found abundantly in nature also makes the sponge affordable, biodegradable, and eco-friendly.”

This study builds on NTU’s body of work on finding new uses for pollen, known as the diamond of the plant kingdom for its hard exterior, by transforming its tough shell into microgel particles. This soft, gel-like material is then used as a building block for a new category of environmentally sustainable materials.

Last year, Prof Cho, together with NTU President Professor Subra Suresh, led a research team to create a paper-like material from pollen as a greener alternative to paper created from trees. This ‘pollen paper’ also bends and curls in response to changing levels of environmental humidity, a trait that could be useful for soft robots, sensors, and artificial muscles.

Prof Cho, who also holds the Materials Research Society of Singapore Chair in Materials Science and Engineering, added: “Pollen that is not used for plant pollination is often considered biological waste. Through our work, we try to find new uses for this ‘waste’ and turn it into a natural resource that is renewable, affordable, and biodegradable. Pollen is also biocompatible. It does not cause an immunological, allergic or toxic reaction when exposed to body tissues, making it potentially suitable for applications such as wound dressing, prosthetics, and implantable electronics.”

The findings were published in the scientific journal Advanced Functional Materials in March.

Building a sponge from pollen

To form the sponge, the NTU team first transformed the ultra-tough pollen grains from sunflowers into a pliable, gel-like material through a chemical process akin to conventional soap-making.

This process includes removing the sticky oil-based pollen cement that coats the grain’s surface, before incubating the pollen in alkaline conditions for three days. The resulting gel-like material was then freeze-dried.

These processes resulted in the formation of pollen sponges with 3D porous architectures. The sponges were briefly heated to 200°C — a step that makes their form and structure stable after repeatedly absorbing and releasing liquids. Heating also led to a two-fold improvement in the sponge’s resistance to deformation, the scientists found.

To make sure the sponge selectively targets oil and does not absorb water, the scientists coated it with a layer of stearic acid, a type of fatty acid found commonly in animal and vegetable fat. This renders the sponge hydrophobic while maintaining its structural integrity.

The scientists performed oil-absorption tests on the pollen sponge with oils and organic solvents of varying densities, such as gasoline, pump oil, and n-hexane (a chemical found in crude oil).

They found that the sponge had an absorption capacity in the range of 9.7 to over 29.3 g/g.* This is comparable to commercial polypropylene absorbents, which are petroleum derivatives and have an absorption capacity range of 8.1 to 24.6 g/g.

They also tested the sponge for its durability and reusability by repeatedly soaking it in silicone oil, then squeezing the oil out. They found that this process could go on for at least 10 cycles.

In a final proof-of-concept experiment, the team tested the ability of a sponge 1.5cm in diameter and 5mm in height to absorb motor oil from a contaminated water sample. The sponge readily absorbed the motor oil in less than 2 minutes.

“Collectively, these results demonstrate that the pollen sponge can selectively absorb and release oil contaminants and has similar performance levels to commercial oil absorbents while demonstrating compelling properties such as low cost, biocompatibility, and sustainable production,” said Prof Cho, the corresponding author of this study.

Going forward, the researchers plan to scale up the size of pollen sponges to meet industry needs. They are also looking to collaborate with non-governmental organisations and international partners to conduct pilot tests with pollen sponges in real-life environments.

“We hope our innovative pollen materials can one day replace widely-used plastics and help to curb the global issue of plastic pollution,” said Prof Cho.

*g/gis a unit of measurementfor absorption capacity. It refers to how many grams of the contaminant can adhere to per gram of the material that absorbs

Michigan State University community ecologist Phoebe Zarnetske is co-lead of the Climate Intervention Biology Working Group, a team of internationally recognized experts in climate science and ecology that is bringing science to bear on the question and consequences of geoengineering a cooler Earth.

The group’s paper, “Potential ecological impacts of climate intervention by reflecting sunlight to cool Earth,” was published in the most recent issue of Proceedings of the National Academy of Sciences, or PNAS.

“There is a dearth of knowledge about the effects of climate intervention on ecology,” said Zarnetske, associate professor in the Department of Integrative Biology in the MSU College of Natural Science and the paper’s lead author. “As scientists, we need to understand and predict the positive and negative effects it could have on the natural world, identify key knowledge gaps and begin to predict what impacts it may have on terrestrial, marine and freshwater species and ecosystems if it were adopted in the future.”

Conversations in 2018 between Jessica Gurevitch, Distinguished Professor in the Department of Ecology and Evolution at Stony Brook University and working group co-lead, and Alan Robock, Distinguished Professor in the Department of Environmental Sciences at Rutgers University, gave rise to the pioneering group, which is more aware than most that geoengineering Earth’s atmosphere is more than just a science fiction scenario.

The costs and technology needed to reflect the sun’s heat back into space are currently more attainable than other climate intervention ideas like absorbing carbon dioxide from the air. The working group anticipates its discussions and open access paper will encourage an explosion of scientific investigation into how a climate intervention strategy known as solar radiation modification, or SRM, in tandem with greenhouse gas emissions reduction, would affect the natural world.

The feasibility of planetary wide SRM efforts hinge on accurate predictions of its myriad outcomes provided by the well-established computer simulations of the Geoengineering Model Intercomparison Project, or GeoMIP. The PNAS paper lays the foundation for expanding GeoMIP’s scope to include the incredible range and diversity of Earth’s ecosystems.

“While climate models have become quite advanced in predicting climate outcomes of various geoengineering scenarios, we have very little understanding of what the possible risks of these scenarios might be for species and natural systems,” Gurevitch said. “Are the risks for extinction, species community change and the need for organisms to migrate to survive under SRM greater than those of climate change, or does SRM reduce the risks caused by climate change?”

“Most of the GeoMIP models only simulate abiotic variables, but what about all of the living things that are affected by climate and rely on energy from the sun?” Zarnetske said, who is also a faculty member of MSU’s Ecology, Evolution and Behavior Program. “We need to better understand the possible impacts of SRM on everything from soil microorganisms to monarch butterfly migrations to marine systems.”

Zarnetske’s Spatial and Community Ecology Lab, or SpaCE Lab, specializes in predicting how ecological communities respond to climate change across scales from the microcosm to the global, making it uniquely poised to assist the working group in illuminating vital data for future SRM scenarios such as stratospheric aerosol intervention, or SAI, the focus of the paper.

SAI would reduce some of the sun’s incoming radiation by reflecting sunlight back into space, such as what happens after large volcanic eruptions. Theoretically, it would be possible to continuously replenish the cloud and control its thickness and location to achieve a desired target temperature.

But the paper reveals the under researched complexity of cascading relationships between ecosystem function and climate under different SAI scenarios. In fact, the scientists argue that climate change mitigation must continue regardless of whether SRM is adopted, and the question remains whether some or any SRM can be beneficial in addition to decarbonization efforts.

“Although SAI may cool Earth’s surface to a global temperature target, the cooling may be unevenly distributed, affecting many ecosystem functions and biodiversity,” Zarnetske said. “Rainfall and surface ultraviolet radiation would change, and SAI would increase acid rain and would not mitigate ocean acidification.”

In other words, SRM is not a magic bullet for solving climate change. Until the working group’s efforts inspire new research into the effects of different climate intervention scenarios, SRM is more akin to a shot in the dark.

“Participating in this working group has been quite eye-opening for me,” said Peter Groffman, ecosystem ecologist and professor at the Advanced Science Research Center at the CUNY Graduate Center and the Cary Institute of Ecosystem Studies. “I was unaware that modeling climate intervention was so advanced, and I think that climate modelers were unaware of the complexities of the ecological systems being affected. It is a strong reminder of the importance of the need for multidisciplinary analysis of complex problems in environmental science.”

“We hope that this paper will spark a lot more attention to this issue and greater cooperation between scientists in the fields of climate science and ecology,” Gurevitch said.

Against the backdrop of steadily warming temperatures and decreasing total yearly rainfall, rain has been falling in fewer and sometimes larger storms, with longer dry intervals between. Total yearly rainfall has decreased by an average of four inches over the last half century, while the longest dry period in each year increased from 20 to 32 days across the West, explained co-senior author Joel Biederman, a research hydrologist with the ARS Southwest Watershed Research Center in Tucson, Arizona.

“The greatest changes in drought length have taken place in the desert Southwest. The average dry period between storms in the 1970s was about 30 days; now that has grown to 45 days,” Biederman said.

Extreme droughts are also occurring more often in the majority of the West according to historical weather data as there has been an increase in the year-to-year variation of both total rainfall amounts and the duration of dry periods.

Biederman emphasized the growing fluctuations in drought and rain patterns as the most significant change.

“Consistency of rainfall, or the lack of it, is often more important than the total amount of rain when it comes to forage continuing to grow for livestock and wildlife, for dryland farmers to produce crops, and for the mitigation of wildfire risks,” Biederman said.

The rate of increasing variability of rainfall within each year and between years also appears to be accelerating, with greater portions of the West showing longer drought intervals since 2000 compared to previous years.

Notable exceptions to these drought patterns were seen in Washington, Oregon and Idaho and the Northern Plains region of Montana, Wyoming, and the most western parts of North and South Dakota. In these regions, the researchers found some increases in total annual rainfall and decreases in drought intervals. Together, these changes support what models have predicted as a consequence of climate change: a northward shift in the mid-latitude jet stream, which brings moisture from the Pacific Ocean to the western United States, according to Biederman.

A critical aspect of this study is the use of actual rainfall data from 337 weather stations spread across the western United States. Biederman contrasted this with the more common use of “gridded” data, which relies on interpolations between reporting stations and tends to smooth out some of the variability revealed by this work.

“Fangyue Zhang, lead author of the manuscript and a post-doctoral researcher on our team, did the hard, painstaking work of compiling and analyzing data from more than 300 weather stations with complete daily records to reveal these changing drought and rainfall patterns,” Biederman said.

“We were surprised to find widespread changes in precipitation have already occurred across large regions of the West. For regions such as the desert Southwest, where changes clearly indicate a trend towards longer, more erratic droughts, research is urgently needed to help mitigate detrimental impacts on ecosystem carbon uptake, forage availability, wildfire activity, and water availability for people,” said co-senior author William K. Smith, assistant professor, University of Arizona.