Climate change to push species over abrupt tipping points

Peer-Reviewed Publication

UNIVERSITY COLLEGE LONDON

Climate change is likely to abruptly push species over tipping points as their geographic ranges reach unforeseen temperatures, finds a new study led by a UCL researcher.

The new Nature Ecology & Evolution study predicts when and where climate change is likely to expose species across the globe to potentially dangerous temperatures.

The research team from UCL, University of Cape Town, University of Connecticut and University at Buffalo analysed data from over 35,000 species of animals (including mammals, amphibians, reptiles, birds, corals, fish, cephalopods and plankton) and seagrasses from every continent and ocean basin, alongside climate projections running up to 2100.

The researchers investigated when areas within each species’ geographical range will cross a threshold of thermal exposure, defined as the first five consecutive years where temperatures consistently exceed the most extreme monthly temperature experienced by a species across its geographic range over recent history (1850-2014).

Once the thermal exposure threshold is crossed, the animal is not necessarily going to die out, but there is no evidence that it is able to survive the higher temperatures – that is, the research projects that for many species there could be an abrupt loss of habitat due to future climate change.

The researchers found a consistent trend that for many animals, the thermal exposure threshold will be crossed for much of their geographic range within the same decade.

Lead author Dr Alex Pigot (UCL Centre for Biodiversity & Environment Research, UCL Biosciences) said: “It is unlikely that climate change will gradually make environments more difficult for animals to survive in. Instead, for many animals, large swaths of their geographic range are likely to become unfamiliarly hot in a short span of time.

“While some animals may be able to survive these higher temperatures, many other animals will need to move to cooler regions or evolve to adapt, which they likely cannot do in such short timeframes.

“Our findings suggest that once we start to notice that a species is suffering under unfamiliar conditions, there may be very little time before most of its range becomes inhospitable, so it’s important that we identify in advance which species may be at risk in coming decades.”

The researchers found that the extent of global warming makes a big difference: if the planet warms by 1.5°C, 15% of species they studied will be at risk of experiencing unfamiliarly hot temperatures across at least 30% of their existing geographic range in a single decade, but this doubles to 30% of species at 2.5°C of warming.

Dr Pigot added: “Our study is yet another example of why we need to urgently reduce carbon emissions to mitigate the harmful effects climate change is having on animals and plants, and avoid a massive extinction crisis.”

The researchers hope that their study could help with targeting conservation efforts, as their data provides an early warning system showing when and where particular animals are likely to be at risk.

Co-author Dr Christopher Trisos (African Climate and Development Initiative, University of Cape Town) said: “In the past we’ve had snapshots to show the impact of climate change, but here we are presenting the data more like a film, where you can see the changes unfold over time. This shows that for many species the risk is a bit like everything, everywhere, all at once. By animating this process, we hope to help direct conservation efforts before it’s too late, while also showing the potentially catastrophic consequences of letting climate change continue unchecked.”

The researchers say that this pattern of abrupt exposure may be an inevitable feature of living on a round planet – because of the shape of the Earth, there is more area available to species in environments near the hot end of what they are used to, such as in low-lying areas or near the equator.

A previous study by the same lead authors found that even if we stop climate change so that global temperatures peak and start to decline, the risks to biodiversity could persist for decades after.* In another analysis similar to the current study, they found that many species facing unfamiliar temperatures will be living alongside other animals experiencing similar temperature shocks, which could pose grave risks to local ecosystem function.**

The study was supported by the Royal Society, the Natural Environment Research Council, the National Science Foundation (US), the African Academy of Sciences and NASA.

* https://www.ucl.ac.uk/news/2022/jun/biodiversity-risks-persist-well-beyond-future-global-temperature-peak

** https://www.ucl.ac.uk/news/2020/apr/climate-change-could-cause-sudden-biodiversity-losses-worldwide

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JOURNAL

Nature Ecology & Evolution

DOI

10.1038/s41559-023-02070-4 

ARTICLE TITLE

Abrupt expansion of climate change risks for species globally

ARTICLE PUBLICATION DATE

18-May-2023

Engineering: The house that diapers built

Peer-Reviewed Publication

SCIENTIFIC REPORTS

Up to eight percent of the sand in concrete and mortar used to make a single-story house could be replaced with shredded used disposable diapers without significantly diminishing their strength, according to a study published in Scientific Reports. The authors suggest that disposable diaper waste could be used as a construction material for low-cost housing in low- and middle-income countries.

Disposable diapers are usually manufactured from wood pulp, cotton, viscose rayon, and plastics such as polyester, polyethylene, and polypropylene. The majority are disposed of in landfill or by incineration.

Siswanti Zuraida and colleagues prepared concrete and mortar samples by combining washed, dried, and shredded disposable diaper waste with cement, sand, gravel, and water. These samples were then cured for 28 days. The authors tested six samples containing different proportions of diaper waste to measure how much pressure they could withstand without breaking. They then calculated the maximum proportion of sand that could be replaced with disposable diapers in a range of building materials that would be needed to construct a house with a floorplan area of 36 square metres that complies with Indonesian building standards.

The authors found that disposable diaper waste could replace up to ten percent of the sand needed for concrete used to form columns and beams in a three-story house. This proportion increased to 27 percent of sand needed for concrete columns and beams in a single-story house. Up to 40 percent of the sand needed for mortar in partition walls can be replaced with disposable diapers, compared to nine percent of the sand in mortar for floors and garden paving. Together, up to eight percent of the sand in all of the concrete and mortar building materials required to build a single-story house with a floorplan of 36 square metres can be replaced with disposable diaper waste — equivalent to 1.7 cubic metres of waste.

The authors note that wider implementation of their findings would require the involvement of stakeholders in government and waste treatment in developing processes for the large-scale collection, sanitising, and shredding of diaper waste. Additionally, building regulations would need to be modified to allow the use of diaper waste as a construction material.

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Article details

Application of non-degradable waste as building material for low-cost housing

DOI: 10.1038/s41598-023-32981-y

Corresponding Author:

Siswanti Zuraida
The University of Kitakyushu, Japan
Email: b0dbb409@eng.kitakyu-u.ac.jp; siswanti.zuraida@gmail.com

Please link to the article in online versions of your report (the URL will go live after the embargo ends): https://www.nature.com/articles/s41598-023-32981-y

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JOURNAL

Scientific Reports

DOI

10.1038/s41598-023-32981-y 

ARTICLE TITLE

Application of non-degradable waste as building material for low-cost housing

ARTICLE PUBLICATION DATE

18-May-2023

WVU researcher searching for ‘holy grail’ of sustainable bioenergy

Grant and Award Announcement

WEST VIRGINIA UNIVERSITY

 

IMAGE: MEMBERS OF THE BRZOSTEK LAB AT WEST VIRGINIA UNIVERSITY MARVEL AT THE SOIL PIT THEY DUG TO MEASURE HOW MISCANTHUS ROOTS AND SOIL MICROBES CONTRIBUTE TO FORMING LONG-LIVED DEEP SOIL CARBON. PICTURED ARE NOAH WAULS, UNDERGRADUATE STUDENT; EDWARD BRZOSTEK, ASSOCIATE PROFESSOR OF BIOLOGY; JESSICA BURKE, UNDERGRADUATE STUDENT; DOMINICK CIFELLI, MASTER’S STUDENT; AND ZOE PAGLIARO, DOCTORAL STUDENT. view more 

CREDIT: WVU PHOTO

Searches for sustainable bioenergy and climate change solutions may be one in the same, according to a West Virginia University researcher.

Edward Brzostek, associate professor of biology, and his students at the WVU Eberly College of Arts and Sciences are creating mathematical models to predict how bioenergy crops will enhance and store soil carbon through a renewed five-year grant from the U.S. Department of Energy.

Brzostek said he believes the models could present a “win-win” that not only improves soil carbon but spurs renewable bioenergy from biological sources. This includes biofuels like corn ethanol and perennial grasses.

Soil microbes in Brzostek’s model determine how plants might store or lose carbon in the future. That’s something current models haven’t taken into consideration.

“Our model can predict whether a bioenergy crop is going to be a net carbon benefit or actually result in carbon losses,” he said. Variables include whether living roots increase or decrease carbon in the soil and how the processes vary with depth and differences in feedstocks.

Natural climate solutions like regenerative agriculture can help mitigate the effects of climate change. Brzostek’s goal is to determine the most efficient way to facilitate the growth of biofuel sources while cleaning up the environment.

“We don't need any new technology to do this,” he said. “It’s one of the few ways that you can get carbon dioxide out of the atmosphere. The holy grail of bioenergy crops is to make products or fuel while also storing more carbon in the ecosystem. If you can grow a biofuel that enhances soil carbon, that’s a win-win.”

Capturing and storing carbon comes naturally to plants, which take it in through photosynthesis. When the plant dies, the leaf litter and dead root material stay in the soil. From there, different entities go to work on the decaying matter, the vast majority of which is decomposed by bacteria and fungi. When they die, their byproducts — including carbon — remain in the soil.

“It’s like a microbial funnel,” Brzostek said. “And a lot of the questions that we’re asking about soil carbon storage, agricultural management and predicting soil carbon into the future are germane to any ecosystem. They’re fundamental questions in ecology that are important to understanding whether our ecosystems can keep the carbon they have and potentially take up more.”

The research team is also looking at how plants help themselves.

“There’s this growing idea that plants can engineer their soil environment by doing things with their roots,” he said. “They can leak carbon out of their roots that feed the microbes. That makes the microbes happy. They break down soil carbon and then they give the plant nitrogen in return, which it needs to grow.”

Thus far, research has revealed that miscanthus roots can mine the nitrogen from leaf litter without leading to carbon being lost.

The microbes perform an essential role in the process. Fortunately, they’re ubiquitous.

“When you walk out in the forest in West Virginia, the microbes are eating everything,” Brzostek said. “If they weren’t, you’d be drowning in leaf litter.”

His research is carried out under the Center of Advanced Biofuels and Bioproducts Innovation, established in 2017 by the U.S. Department of Energy. CABBI, headquartered at the University of Illinois, brings together 20 partner institutions, universities and national laboratories to research sustainable bioproducts from bioenergy crops.

Decarbonizing the economy is complicated. Wind, solar and nuclear power are renewable, but some industries — like aviation — cannot be decarbonized.

“Bioenergy can play a part in the new bioeconomy,” Brzostek said. “We talk about bioenergy refineries and plants that could produce energy from some bioenergy crop. They’d capture the carbon dioxide and pump it underground. It could lead to a new green industry across much of the rain-fed United States, where you can grow these things.”

WVU students and postdoctoral researchers assisting Brzostek on the research include Joanna Ridgeway, Zoe Pagliaro, Dominick Cifelli, Jessica Burke, Noah Wauls and Stephanie Juice. 

CAPTION

WVU students Joanna Ridgeway and Dominick Cifelli measure carbon dioxide respiration from soil incubations to get an indicator of microbial activity.

CREDIT

WVU Photo

“In the sea everything is connected”: Portugal welcomes International Symposium “Human Impacts on Marine Functional Connectivity”

Meeting Announcement

FACULTY OF SCIENCES OF THE UNIVERSITY OF LISBON

 

IMAGE: THE INTERNATIONAL SYMPOSIUM TAKES PLACE BETWEEN MAY 22-25, 2023, AT SESIMBRA (PORTUGAL). view more 

CREDIT: INTERNATIONAL SYMPOSIUM "HUMAN IMPACTS ON MARINE FUNCTIONAL CONNECTIVITY"

The international symposium “Human Impacts on Marine Functional Connectivity” takes place between May 22-25, 2023, at Sesimbra (Portugal). More than one hundred researchers, marine managers and politicians from 30 countries worldwide share the latest discoveries on this subject and discuss policies for the management and preservation of these ecosystems.

“In the sea everything is connected. Species know no borders. The connections that exist in the ocean are essential for the species that live in it, many of them of extreme importance to us, in our food, for the biodiversity they represent, in the role they play in nature. Phenomena such as climate change, the construction of new infrastructures such as aquaculture units, energy production, bridges, ports and marinas, are some examples of how human action has impacted these connections”, says Susanne Tanner, Researcher at the Faculty of Sciences of the University of Lisbon (Ciências ULisboa) and organizer of this symposium.

In the first three days, there are five thematic sessions moderated by world-renowned researchers, which include more than 60 oral presentations and 30 posters. On the last day, two workshops will take place: the first, at the science-society interface, will discuss the best way to use historical and pre-industrial data to anticipate future changes in species distribution and consequences for marine ecosystems; the second, in the science-policy interface, will discuss how to involve governments and NGOs in the co-creation of actions and tools that incorporate scientific data into decision-making, planning and policy processes for sustainable development.

The symposium has the support of Sesimbra City Council and is organized by the COST SEA-UNICORN Action, by the International Council for the Exploration of the Sea (ICES), and locally by Ciências ULisboa, MARE/ARNET and the Center or Functional Ecology of the University of Coimbra (Portugal)

POLITICAL ECOLOGY

Conservationists propose “global conservation basic income” to safeguard biodiversity

Analysis shows that paying a basic income of $5.50 per day to all residents of protected areas in low- and middle-income countries would cost less than subsidies given to fossil fuels

Peer-Reviewed Publication

WILDLIFE CONSERVATION SOCIETY

 

IMAGE: ANALYSIS SHOWS THAT PAYING A BASIC INCOME OF $5.50 PER DAY TO ALL RESIDENTS OF PROTECTED AREAS IN LOW- AND MIDDLE-INCOME COUNTRIES WOULD COST LESS THAN SUBSIDIES GIVEN TO FOSSIL FUELS view more 

CREDIT: JULIE LARSEN MAHER/WCS

Publishing in the journal Nature Sustainability, a team of conservationists led by the Wildlife Conservation Society say that providing a “Conservation Basic Income” (CBI) – of $5.50 per day to all residents of protected areas in low- and middle-income countries would cost less than annual subsidies given to fossil fuels and other environmentally harmful industries.

CBI is an unconditional cash payment to individuals, similar to universal basic income (UBI)10 but targeting residents of important conservation areas. A Conversation Basic Income would support stewardship of land and biodiversity by Indigenous Peoples and local communities.

The authors provided the first global estimates for the gross costs of CBI using spatial analyses of three plausible future conservation scenarios. Gross costs vary widely, depending on the areas and populations included as well as the payment amounts: from $351 billion to $6.73 trillion annually.

The authors say a CBI is a potentially powerful mechanism for facilitating a radical shift in conservation. They say that evidence from other poverty-alleviation cash transfer programs that are unconditional with respect to conservation outcomes suggest that a CBI could achieve conservation in many contexts. For example, Indonesia’s national program of anti-poverty cash transfers also reduced deforestation across Indonesia.

Said lead author Dr. Emiel de Lange of WCS’s Cambodia Program: “CBI more equitably distributes the costs and benefits of conservation because basic income schemes improve wellbeing, reduce poverty, and redress inequalities including gender inequity. Inequalities, including gender, are key drivers of biodiversity loss. CBI could enable communities to pursue their own visions of a good life and avoid exploitation by extractive industries. Moreover, through redistribution of wealth from affluent populations and/or harmful industries, CBI can reduce aggregate global consumption and environmental impact.”

These costs of a CBI are significant compared to current government conservation spending, (~$133 billion in 2020) but represent a potentially sensible investment in safeguarding incalculable social and natural values as well as the estimated $44 trillion in global economic production dependent on nature.

READ THE STUDY HERE.

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JOURNAL

Nature Sustainability

DOI

10.1038/s41893-023-01115-7 

METHOD OF RESEARCH

Meta-analysis

SUBJECT OF RESEARCH

People

ARTICLE TITLE

A global conservation basic income to safeguard biodiversity

ARTICLE PUBLICATION DATE

18-May-2023

Perfection: The Enemy of Evolution

Freedom to miss the optimal mark opens a wide range of new designs over time

Peer-Reviewed Publication

DUKE UNIVERSITY

DURHAM, N.C. -- Scientists are often trained to seek out the absolute best solution to a given problem. On a chalk board, this might look something like drawing a graph to find a function’s minimum or maximum point. When designing a turbojet engine, it might mean tweaking the rotor blades’ angles a tiny degree to achieve a tenth of a percent increase in efficiency.

Adrian Bejan, the J.A. Jones Distinguished Professor of Mechanical Engineering at Duke University, was busy demonstrating the former for a class full of students when a thought struck him: this is not how nature operates. Evolution is a sequence of design changes happening on their own in a discernible direction; it never weds itself to a single point on a drawing board. An evolving system or animal is free to simply go with what works. Not so much that its performance suffers greatly, but enough that it opens access to other options near the so-called optimal design.

With science often looking to nature for clues to solve challenges, Bejan wondered if he might look the opposite way, to predict nature before looking at it. If problem solvers and builders were free to miss the absolute highest mark, how much greater might be the range of designs they consider plausible?

That’s the question that Bejan posits in a new paper published online May 16 in the journal Biosystems. Using two relatively simple examples — walkways ferrying passengers off a train and a bird flapping its wings — he discovers that the answer is, “quite a lot.”

“In engineering, design, theater, architecture or even the organization of this university, any form of design benefits from the ability to make good but imperfect decisions and the freedom to move on and contemplate other opportunities for improvement,” Bejan said. “If one is wedded to the idea of the absolute best, nothing new will ever be created.”

In the paper, Bejan first looks at the example of passengers arriving by train and walking across a room with many exit points. With the total area of the room remaining constant but the length and width of the room free to change, he solves for the optimal shape of the room to get all passengers where they’re going the quickest. With the solution equations in hand, he shows that providing even 1% wiggle room for imperfection away from the best performance opens the design space by 28%.

In his second example, Bejan looks at the flapping motion of birds at nearly constant altitude and speed. Considering the various forces involved — drag during gliding, lift created by wing size, speed and body size, among others — he formulates an equation for the rhythm of wings needed to maintain constant speed with minimum effort. While an optimal answer does exist, Bejan once again shows that allowing for just 1% imperfection above the theoretical minimum effort opens the design space by 20%.

Bejan says that he chose these examples because they involved changing only a single variable, a single degree of freedom — the shape for a room or the flapping rhythm for a wing. In more complex examples that involve many variables, these tiny tolerances for imperfection create an even wider range of “good enough” solutions.

The lesson learned is that science now has a predictive idea of how nature works. By focusing less on finding absolute optimal designs, researchers may use the freedom to iteratively move toward entirely new design concepts that wouldn’t otherwise have been within their sight. It also gives designs, methods and entire fields of study the ability to adapt to a changing world.

“The doctrine of chasing the best design is not helpful,” Bejan said. “The teaching of science should go hand-in-hand with the freedom to take a shot, hit the vicinity of the mark and move on. The end goal isn’t just to hit a bullseye, but to keep more arrows in your quiver to keep taking shots over a long period of time.”

This work was supported by a grant from CaptiveAire Systems.

CITATION: “Perfection is the Enemy of Evolution,” Adrian Bejan. Biosystems, Volume 229, July 2023. DOI: 10.1016/j.biosystems.2023.104917

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JOURNAL

Biosystems

DOI

10.1016/j.biosystems.2023.104917 

METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Perfection is the Enemy of Evolution

From Seattle to space: Science that began at the Allen Institute blasts off to International Space Station

For the first time astronauts will transport Allen Institute cells into space where Cedars-Sinai researchers will study the effects of microgravity.

Business Announcement

ALLEN INSTITUTE

 

IMAGE: CELLS FROM THE SOX2-GFP REPORTER LINE view more 

CREDIT: ALLEN INSTITUTE FOR CELL SCIENCE

SEATTLE — May 18, 2023 — This Sunday (May 21) at 2:37 p.m. PDT1, astronauts from Axiom Space in partnership with Cedars-Sinai will blast off to the International Space Station carrying cells from the Allen Institute for Cell Science, a division of the Allen Institute. There, Axiom Space astronauts will perform experiments and send real-time data back to researchers at Cedars-Sinai as part of their study on the effects of microgravity on human cells.

The experiments are part of the Ax-2 mission, funded by NASA and Axiom Space, and represent a major milestone: It will be the first time Allen Institute-generated cells are flown to space. These cells are part of the publicly available Allen Cell Collection, a suite of human induced pluripotent stem cells gene-edited to illuminate different parts of the cell. 

Images and videos of the cells are available here.

"The original purpose of this collection was to understand how the major organelles or ‘parts’ inside a normal human cell are arranged and how they change as the cell performs different functions or even becomes a different cell type over time. From that foundation we and others can then probe and understand how various perturbations such as human disease affect our cells,” said Ruwanthi Gunawardane, Ph.D., Executive Director of the Allen Institute for Cell Science. “Microgravity is a powerful condition to test the potential and the limits of what cells can do. We never envisioned our cells making it to space when we created this collection, but we’re very excited to see what we can learn from these experiments.”

Specifically, two types of experiments will be conducted during the five-day mission:

1. Cell Proliferation

Using the cell line from the Allen Cell Collection that was gene edited to illuminate specific cell structures, researchers from Cedars-Sinai will explore whether microgravity can be used to improve stem cell proliferation. Earlier studies have shown that stem cells can grow faster in microgravity, and the new mission’s findings could lead to more efficient stem cell production for research and, ultimately, for medical applications.

2. Cell Transfection

Cedars-Sinai researchers will investigate whether DNA can be effectively introduced into the cells (transfection) in microgravity. This early test will be a vital milestone for future experiments, such as introducing stem cell reprogramming factors or modifying the cell’s DNA itself.

Pluripotent stem cells are a useful investigative tool because they transform into nearly any cell type found in the human body. This is important for downstream clinical applications that may use these cells for therapy, such as repairing cardiac tissue after a heart attack.

“The cell lines that the Allen Institute has produced for the community are a tremendous resource,” said Arun Sharma, Ph.D., a stem cell biologist in the Board of Governors Regenerative Medicine Institute, Department of Biomedical Sciences, Cancer Institute, and Smidt Heart Institute at Cedars-Sinai. “These particular cells that are making the journey to space are from a beautiful cell line to work with, because you can see them glowing green when they are most potent. It’s a great visual readout for how healthy our cells will be in microgravity.”

If the experiments successfully demonstrate that pluripotent stem cells can grow better, faster, or more efficiently in microgravity, that insight could open the door to biomedical research in space in service of human health.

 Cells 2 (Video) [VIDEO] | 

About the Allen Institute for Cell Science
Allen Institute for Cell Science, a division of the Allen Institute, an independent, 501(c)(3) nonprofit medical research organization, is dedicated to understanding and modeling cells: the fundamental units of life. By integrating technologies, approaches, models and data into a common standardized framework, the Allen Institute for Cell Science is creating dynamic, visual models of how genetic information is transformed into cellular behavior, and how the molecules and organelles within each cell interact and function as systems. These predictive models will enable the cell science community to better understand the role of cells in both health and disease. The Allen Institute for Cell Science was launched in 2014 with a contribution from founder and philanthropist, the late Paul G. Allen. The data, tools and models from the Allen Institute for Cell Science are publicly available online at allencell.org.

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1. Subject to change based on conditions. Backup date is May 22

In schools, masks and air cleaners were associated with stopping COVID-19

Study of two Swiss schools shows the virus spread frequently among students during Omicron wave

Peer-Reviewed Publication

PLOS

 

IMAGE: NEW STUDY FINDS THAT MASKING AND PORTABLE AIR CLEANERS WERE ASSOCIATED WITH REDUCING THE SPREAD OF THE VIRUS THAT CAUSES COVID-19 IN TWO SWISS SCHOOLS. view more 

CREDIT: MARCO FILECCIA, UNSPLASH (CC0, HTTPS://CREATIVECOMMONS.ORG/PUBLICDOMAIN/ZERO/1.0/)

A new study shows that masking and portable air cleaners reduced the spread of the virus that causes COVID-19 in two Swiss schools. A team led by Nicolas Banholzer and Kathrin Zürcher of the University of Bern, Switzerland, publish these findings on May 18th in the open access journal PLOS Medicine.

During the early part of the COVID-19 pandemic, public health authorities worldwide closed schools to prevent the virus’ spread. This decision sparked intense debate over the role of school children in transmission – a risk that is still poorly understood. In the new study, researchers used molecular, environmental and epidemiological data to understand how the virus that causes COVID-19 spread in two secondary schools in Switzerland, from January to March 2022 during the Omicron wave. The study included 90 students and looked at viral transmission in classes with and without masking or air cleaners.

The researchers consistently detected salivary and airborne SARS-CoV-2, the virus that causes COVID-19, in air samples and samples from students throughout the study period. However, concentrations of airborne SARS-CoV-2 were, on average, 70% lower with mask mandates and 40% lower with air cleaners. The findings suggest that between 2 and 19 infections could be avoided while masks were mandated.

The levels of airborne virus detected within the schools indicated that SARS-CoV-2 was continually transmitting among students, and that mask mandates were highly effective at reducing airborne concentrations, thus potentially preventing transmission. The researchers conclude that this monitoring approach could be used during future epidemics of respiratory viral infections to help understand transmission patterns, and whether suggested infection control measures are effective in reducing transmission.

Coauthor Lukas Fenner adds, “Although our study has several limitations, including the observational nature of our study and that detecting SARS-CoV-2 in the air or aerosols does not necessarily mean transmission, we found that mask mandates reduced transmission in classrooms, and both masks and air cleaners reduced aerosol concentrations.”

#####

In your coverage, please use this URL to provide access to the freely available paper in PLOS Medicine: http://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1004226

Citation: Banholzer N, Zürcher K, Jent P, Bittel P, Furrer L, Egger M, et al. (2023) SARS-CoV-2 transmission with and without mask wearing or air cleaners in schools in Switzerland: A modeling study of epidemiological, environmental, and molecular data. PLoS Med 20(5): e1004226. https://doi.org/10.1371/journal.pmed.1004226

Author Countries: Switzerland, South Africa, United Kingdom

Funding: see manuscript

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JOURNAL

PLoS Medicine

DOI

10.1371/journal.pmed.1004226 

METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

People

COI STATEMENT

Competing interests: I have read the journal’s policy and the authors of this manuscript have the following competing interests: ME serves on PLOS Medicine’s editorial board. All authors have declared that no competing interests exist.

Amputees feel warmth in their missing hand

Peer-Reviewed Publication

ECOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE

 

VIDEO: INTERVIEW WITH RESEARCHERS, AMPUTEE view more 

CREDIT: PART I : FOR THE FIRST 2:57 MINUTES, CC-BY-SA , CREDIT: EPFL. PART II: FROM 2:57 - 4:00, COPYRIGHT: CENTRO PROTESI INAIL

“When I touch the stump with my hand, I feel tingling in my missing hand, my phantom hand. But feeling the temperature variation is a different thing, something important... something beautiful,” says Francesca Rossi.

Rossi is an amputee from Bologna, Italy. She recently participated in a study to test the effects of temperature feedback directly to the skin on her residual arm. She is one of 17 patients to have felt her phantom, missing hand, change in temperature thanks to new EPFL technology. More importantly, she reports feeling reconnected to her missing hand.

“Temperature feedback is a nice sensation because you feel the limb, the phantom limb, entirely. It does not feel phantom anymore because your limb is back,” Rossi continues.

Researchers Silvestro Micera and Solaiman Shokur have been keen on incorporating new sensory feedback into prosthetic limbs for providing more realistic touch to amputees, and their latest study focuses on temperature. They stumbled upon a discovery about temperature feedback that far exceeds their expectations.

If you place something hot or cold on the forearm of an intact individual, that person will feel the object’s temperature locally, directly on their forearm. But in amputees, that temperature sensation on the residual arm may be felt­… in the phantom, missing hand.

By providing temperature feedback non-invasively, via thermal electrodes (aka thermodes) placed against the skin on the residual arm, amputees like Rossi report feeling temperature in their phantom limb. They can feel if an object is hot or cold, and can tell if they are touching copper, plastic or glass.  In a collaboration between EPFL, Sant’Anna School of Advanced Studies (SSSA) and Centro Protesi Inail, the technology was successfully tested in 17 out of 27 patients. The results are published in Science.

“Of particular importance is that phantom thermal sensations are perceived by the patient as similar to the thermal sensations experienced by their intact hand," explains Shokur, EPFL senior scientist neuroengineer who co-led the study.

 

 

Towards realistic bionic touch

The projection of temperature sensations into the phantom limb has led to the development of new bionic technology, one that equips prosthetics with non-invasive temperature feedback that allows amputees to discern what they’re touching.

“Temperature feedback is essential for relaying information that goes beyond touch, it leads to feelings of affection. We are social beings and warmth is an important part of that,” says Micera, Bertarelli Foundation Chair in Translational Neuroengineering, professor at EPFL and SSSA who also co-led the study.  “For the first time, after many years of research in my laboratory showing that touch and position information can be successfully delivered, we envisage the possibility of restoring all of the rich sensations that one’s natural hand can provide.”

 

Temperature feedback, from well-being to prosthetics

A few years ago, Micera and Shokur got wind of a system that could provide temperature feedback through the skin of healthy subjects, also developed at EPFL and spun-off by Metaphysiks.

Metaphysiks has been developing neuro-haptic technology, MetaTouch, which connects the body with digital worlds. MetaTouch combines touch and temperature feedback to augment physical products for well-being. 

“This breakthrough highlights the power of haptics to improve medical conditions and enhance the quality of life for people with disabilities,” says Simon Gallo, Co-founder and Head of Technology at Metaphysiks.

The EPFL neuroengineers borrowed MetaTouch that provides thermal feedback directly to a user’s skin. With this device, they discovered the thermal phantom sensations and subsequently tested it in 27 amputees.

 

The Minitouch prototype and tests

For the study, Shokur and Micera developed the MiniTouch, a device that provides thermal feedback and specifically built for integration into wearable devices like prosthetics. The MiniTouch consists of a thin, wearable sensor that can be placed over an amputee’s prosthetic finger. The finger sensor detects thermal information about the object being touched, more specifically, the object’s heat conductivity.  If the object is metallic, it will naturally conduct more heat or cold than, for instance, a plastic one.  A thermode, one that is in contact with the skin on the amputee’s residual arm, heats up or cools down, relaying the temperature profile of the object being touched by the finger sensor.

“When we presented the possibility to get back temperature sensation on the phantom limb or the possibility to feel the contact with different materials, we obtained a lot of positive feedback.  And eventually, we were able to recruit more than 25 volunteers in less than two years,” says Federico Morosato who was responsible for organizing the clinical aspect of the trials at Centro Protesi Inail.

The scientists found that small areas of skin on the residual arm project to specific parts of the phantom hand, like the thumb, or the tip of an index finger. As expected, they discovered that the mapping of temperature sensations between the residual arm and the entire projected phantom one is unique to each patient.

 

Bionic prosthetics for repairing the human body

Almost a decade ago, Micera and colleagues provided real-time sensory feedback about objects being grasped. They went on to improve touch resolution by providing feedback about an object’s texture and position information in a reliable way. Moreover, they discovered that amputees begin to embody their prosthetic hand if provided with sensory feedback directly into their intact nervous system. The added sensation of temperature feedback is yet another step towards building bionic prosthetics for repairing the human body. Fine-tuning temperature sensations and integrating these into a wearable device that can be mapped out to each patient are part of the next steps.

 

 

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JOURNAL

Science

DOI

10.1126/science.adf6121 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

People

ARTICLE PUBLICATION DATE

18-May-2023