Purifying water with the power of the sun

A Notre Dame researcher’s invention could improve access to clean water for some of the world’s most vulnerable people.

 “Today, the big challenges are information technology and energy,” says László Forró, the Aurora and Thomas Marquez Professor of Physics of Complex Quantum Matter in the University of Notre Dame's Department of Physics and Astronomy. “But tomorrow, the big challenge will be water.”

The World Health Organization reports that today nearly 2 billion people regularly consume contaminated water. It estimates that by 2025 half of the world’s population could be facing water scarcity. Many of those affected are in rural areas that lack the infrastructure required to run modern water purifiers, while many others are in areas affected by war, natural disasters or pollution. There is a greater need than ever for innovative ways to extend water access to those living without power, sanitation and transportation networks.

Recently, Forró's lab developed just such a solution. They created a water purifier, described in the Nature partner journal Clean Water, that is powered by a resource nearly all of the world’s most vulnerable people have access to: the sun.

Humans are Leading Source of Death for California Mountain Lions, Despite Hunting Protections

A female mountain lion (P-19) near Malibu Creek State Park in March 2014.
Photo Credit: National Park Service

Mountain lions are protected from hunting in California by a law passed by popular vote in 1990. However, a team of researchers working across the state found that human-caused mortality—primarily involving conflict with humans over livestock and collisions with vehicles—was more common than natural death for this protected large carnivore.

The study, published today in the Proceedings of the National Academy of Sciences, was led by the University of Nebraska-Lincoln, along with a broad team of coauthoring California researchers, including from the University of California, Davis.

Most research on mountain lions is conducted at relatively small scales, which limits understanding of mortality caused by humans across the large areas they roam. To address this, scientists from multiple universities, government agencies, and private organizations teamed up to better understand human-caused mortality for mountain lions across the entire state of California.

The team tracked almost 600 mountain lions in 23 different study areas, including the Sierra Nevada mountains, the northern redwoods, wine country north of San Francisco, the city of Los Angeles, and many other areas of the state.

Artificial light at night aids caterpillar predators

Under moderate levels of artificial light, predators have more opportunity to attack caterpillars.
Photo Credit: John Deitsch/Cornell University  

To save caterpillars, turn off your porch light.

Moderate levels of artificial light at night – like the fixture illuminating your backyard – bring more caterpillar predators and reduce the chance that these lepidoptera larvae grow up to become moths and serve as food for larger prey.

This new Cornell research was published March 8 in the Proceedings of the Royal Society B: Biological Sciences.

Scientists can place clay models that look like caterpillars in the woods. Due to the soft clay, the researchers can examine the marks and get a sense of how often larvae are attacked by predators.

The Cornell scientists placed more than 550 soft clay caterpillar models – lifelike replicas – in a forest setting to ascertain how the mockups were attacked and hunted by predators, compared to a control group.

Researchers Separate Cotton from Polyester in Blended Fabric

A cotton knit fabric dyed blue and washed 10 times to simulate worn garments is enzymatically degraded to a slurry of fine fibers and "blue glucose" syrup that are separated by filtration - both of these separated fractions have potential recycle value.
Photo Credit: Sonja Salmon.

In a new study, North Carolina State University researchers found they could separate blended cotton and polyester fabric using enzymes – nature’s tools for speeding chemical reactions. Ultimately, they hope their findings will lead to a more efficient way to recycle the fabric’s component materials, thereby reducing textile waste.

However, they also found the process needs more steps if the blended fabric was dyed or treated with chemicals that increase wrinkle resistance.

“We can separate all of the cotton out of a cotton-polyester blend, meaning now we have clean polyester that can be recycled,” said the study’s corresponding author Sonja Salmon, associate professor of textile engineering, chemistry and science at NC State. “In a landfill, the polyester is not going to degrade, and the cotton might take several months or more to break down. Using our method, we can separate the cotton from polyester in less than 48 hours.”

Widespread species are gaining even more ground, new study shows

The cabezon Scorpaenichthys marmoratus
Photo Credit: Steve Lonhart (SIMoN / MBNMS)

Widespread animal and plant species benefit from human impacts on nature and can spread even further. In contrast, species with a small range retreat even further. This is shown in a new study by the German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig and the Martin Luther University Halle-Wittenberg (MLU), which was published in "Nature Communications". The team analyzed data from over 200 studies and was able to show that protected areas can mitigate some of the effects of biodiversity change and slow down the systematic decline of less common species.

Every living species on the planet has its own unique geographic range, with some species occurring over large parts of the globe, while others inhabiting only a few select areas. But does the range size of a species influence how it responds to human activities and changes in the number of sites it occupies over time?

A team led by researchers from iDiv and MLU set out to evaluate the connection between the size of a species’ range and the changes in their regional occupancy over time. To do so, the researchers used an extensive dataset of 238 studies that monitored plant and animal species assemblages from across many sites for 10-90 years. From these time series, they were able to determine which species were increasing in the numbers of sites they occupied through time, which were decreasing in their site occupancy, and which stayed the same. They then wanted to compare the trends of species to the size of their ranges to see if there was a connection. To determine the range sizes of nearly 19,000 species from across the tree-of-life that were identified in the time series, they used data from the Global Biodiversity Information Facility (GBIF), which includes data on the occurrences of species from across the world, including data collected from popular smartphone apps like iNaturalist and eBird.

Parasites alter likelihood of fish being caught by anglers

Itsuro Koizumi (second from left) and Ryota Hasegawa (first from right), authors of the paper, with Taro Matsuda of Setsunan University (center), and Masashiro Naka (first from left) and Chiharu Furusawa (second from right) of the Koizumi lab
Photo Credit: Itsuro Koizumi

Parasitic infections in salmonid fish can increase or decrease their vulnerability to angling, depending on their body condition.

Angling, a type of fishing, is a popular pastime across the world, and is known to be 40,000 years old. Angling usually takes place in natural bodies of water, which may have populations of wild fish, or be stocked with cultured fish. Fish caught by angling may either be consumed, or may be immediately released.

Parasites are very common in nature, found everywhere that their hosts are found. Parasites are known to alter the susceptibility of fish to predators. Angling can be considered predation of fish; however, there has been almost no in-depth research on how parasites affect the susceptibility of fish to angling.

Associate Professor Itsuro Koizumi at the Faculty of Environmental Earth Science, Hokkaido University, and graduate student Ryota Hasegawa have investigated how a mouth and gill parasite of the whitespotted char, a salmonid fish, affects its vulnerability to angling. Their findings were published in the journal The Science of Nature.

New study counts the environmental cost of managing knotweed

Invasive Knotweed
Photo Credit: Courtesy of Swansea University

New Swansea University research has looked at the long-term environmental impact of different methods to control Japanese knotweed.

The invasive species has been calculated to cost more than £165 million to manage every year in the UK alone. Its presence can blight property purchases for households across the country.

This has led to the development of different ways of trying to control it but with sustainability becoming increasingly important, understanding the effect of these management methods is vital.

A new study, led by biosciences lecturer Dr Sophie Hocking and looking at the entire life cycle and long-term impacts of different management approaches, has just been published in online journal Scientific Reports.

Dr Hocking said: “In light of the current climate emergency and biodiversity crisis, invasive species management and sustainability have never been so important.

New Study Provides First Comprehensive Look at Oxygen Loss on Coral Reefs

Coral reefs at a study site off Taiping Island, South China Sea.
Photo Credit: Yi Bei Liang

Scripps Oceanography scientists and collaborators provide first-of-its-kind assessment of hypoxia, or low oxygen levels, across 32 coral reef sites around the world

A new study is providing an unprecedented examination of oxygen loss on coral reefs around the globe under ocean warming. Led by researchers at UC San Diego’s Scripps Institution of Oceanography and a large team of national and international colleagues, the study captures the current state of hypoxia—or low oxygen levels—at 32 different sites, and reveals that hypoxia is already pervasive on many reefs.

The overall decline of oxygen content across the world’s oceans and coastal waters—a process known as ocean deoxygenation—has been well documented, but hypoxia on coral reefs has been relatively underexplored. Oxygen loss in the ocean is predicted to threaten marine ecosystems globally, though more research is needed to better understand the biological impacts on tropical corals and coral reefs.

The study, published March 16 in the journal Nature Climate Change, is the first to document oxygen conditions on coral reef ecosystems at this scale.

Climate change creates ‘win-win’ between bald eagles and farmers

Bald eagle
Photo Credit: Brian E. Kushner/Lab of Ornithology 

As they seek new foods because climate change has altered their traditional diet of salmon carcasses, bald eagles in northwestern Washington state have become a boon to dairy farmers, deterring pests and removing animal carcasses from their farms, a new study finds.

The mutually beneficial relationship is described in “A Win-Win Between Farmers and an Apex Predator: Investigating the Relationship Between Bald Eagles and Dairy Farms,” which published March 10 in the journal Ecosphere.

“The narrative around birds of prey and farmers has traditionally been negative and combative, mainly due to claims of livestock predation,” said lead author Ethan Duvall, a doctoral student in ecology and evolutionary biology. “However, dairy farmers in northwestern Washington do not consider the eagles threats. In fact, many farmers appreciate the services that the eagles provide such as carcass removal and pest-deterrence.”

Plants adapt to climate disruptions to lure pollinators

Morning glory flowers at U-M’s Matthaei Botanical Gardens.
Photo Credit: Malia Santos

There’s been a well-documented shift toward earlier springtime flowering in many plants as the world warms. The trend alarms biologists because it has the potential to disrupt carefully choreographed interactions between plants and the creatures—butterflies, bees, birds, bats and others—that pollinate them.

But much less attention has been paid to changes in other floral traits, such as flower size, that can also affect plant-pollinator interactions, at a time when many insect pollinators are in global decline.

In a study published online in the journal Evolution Letters, two University of Michigan biologists and a University of Georgia colleague show that wild populations of the common morning glory in the southeastern United States increased the size of their flowers between 2003 and 2012.

Increased flower size suggests a greater investment by the plants in pollinator attraction, according to the researchers. The changes were most pronounced at more northern latitudes, in line with a broad range of previous work showing that northern plant populations tend to show more dramatic evolutionary responses to climate change.

Low-cost device can measure air pollution anywhere

MIT researchers have made an open-source version of the “City Scanner” mobile pollution detector that lets people check air quality anywhere, cheaply. Pictured are some examples of the latest version of the device, called Flatburn, as well as a researcher attaching a prototype to a car.
Image Credits: Courtesy of the researchers. Edited by MIT News
(CC BY-NC-ND 3.0)

Air pollution is a major public health problem: The World Health Organization has estimated that it leads to over 4 million premature deaths worldwide annually. Still, it is not always extensively measured. But now an MIT research team is rolling out an open-source version of a low-cost, mobile pollution detector that could enable people to track air quality more widely.

The detector, called Flatburn, can be made by 3D printing or by ordering inexpensive parts. The researchers have now tested and calibrated it in relation to existing state-of-the-art machines, and are publicly releasing all the information about it — how to build it, use it, and interpret the data.

“The goal is for community groups or individual citizens anywhere to be able to measure local air pollution, identify its sources, and, ideally, create feedback loops with officials and stakeholders to create cleaner conditions,” says Carlo Ratti, director of MIT’s Senseable City Lab. 

“We’ve been doing several pilots around the world, and we have refined a set of prototypes, with hardware, software, and protocols, to make sure the data we collect are robust from an environmental science point of view,” says Simone Mora, a research scientist at Senseable City Lab and co-author of a newly published paper detailing the scanner’s testing process. The Flatburn device is part of a larger project, known as City Scanner, using mobile devices to better understand urban life.

Humans are altering the diet of Tasmanian devils, which may accelerate their decline

The researchers investigated the diets of devils from habitats of differing levels of disturbance.
Photo Credit: Ariana Ananda.

New research shows how human-modified landscapes affect the diets of these marsupial scavengers.

The Tasmanian devil roams the island state of Australia as the apex predator of the land, feeding on whatever it pleases as the top dog – or the top devil. But some of these marsupial scavengers could be starting to miss out on a few items from the menu.

According to a study led by UNSW Sydney, living in human-modified landscapes could be narrowing the diet of the Tasmanian devil. The research, published recently in Scientific Reports, suggests devils have access to vastly different cuisines depending on the type of environment they live in.

“We found Tasmanian devil populations had different levels of variation in their diet depending on their habitat,” says Anna Lewis, a PhD candidate at UNSW Science and lead author of the study. “The more that habitat was impacted by humans, the more restrictive the diet became.”

A previous study by the team found most devils are individual specialists, feeding on the same food items consistently over time. But human impacts could be influencing whether they have access to their favorite foods.

“How humans change the environment impacts the animals within them,” says Professor Tracey Rogers, an ecologist at UNSW Science and senior author of the study. “Even small changes can have significant consequences for devils, so we need to be mindful of the consequences of our actions.”

Dry forests and savannas vital for Brazil’s climate goals

Cerrado savanna
Photo Credit Tim Hill

Brazil must protect and restore its dry forests and savannas to achieve its climate goals, new research shows.

Attention in Brazil and worldwide often focusses on the Amazon rainforest – ignoring damage and destruction of these seasonally dry biomes, which contain vast biodiversity and carbon stores.

The new study, led by the universities of Exeter and Campinas, says cost-effective restoration of savannas and dry forests could lock in 1.5 billion tons of carbon in 100 years.

But restoration takes time, and the researchers say protecting existing ecosystems is the best option for Brazil to reach its 2030 climate goals.

“Ongoing land-use change – especially the destruction of ecosystems to create agricultural land – makes Brazil the world’s fifth-biggest greenhouse gas emitting country,” said Dr Lucy Rowland, from Global Systems Institute at the University of Exeter.

Game-changing high-performance semiconductor material could help slash heat emissions

WVU researchers Sergio Andres Paredes Navia, Cesar Octavio Romo de la Cruz, Liang Liang and Ellena Gemmen use an electron microscope to study the nanostructure of a new oxide ceramic material with the potential to make thermoelectric generators efficient enough to capture a significant portion of the waste heat that industrial systems like power plants emit.
Photo Credit: Courtesy of West Virginia University

Researchers at West Virginia University have engineered a material with the potential to dramatically cut the amount of heat power plants release into the atmosphere.

A team led by Xueyan Song, professor and George B. Berry Chair of Engineering at the Benjamin M. Statler College of Engineering and Mineral Resources, has created an oxide ceramic material that solves a longstanding efficiency problem plaguing thermoelectric generators. Those devices can generate electricity from heat, including power plant heat emissions, which contribute to global warming.

The breakthrough oxide ceramic Song’s team produced “achieved a record-high performance that had been deemed impossible,” she said. “We demonstrated the best thermoelectric oxide ceramics reported in the field worldwide over the past 20 years, and the results open up new research directions that could further increase performance.”

Oxide ceramics are from the same family as materials like pottery, porcelain, clay bricks, cement and silicon, but contain various metallic elements. They’re hard, resistant to heat and corrosion, and well-suited for high-temperature applications in air. They can serve as the material for thermoelectric generator components.

Cow dung possible sustainable material of the future, study finds

Photo Credit: Jonas Koel

Livestock dung could be used to create the next generation of cellulosic materials, according to a new report.

Livestock dung is typically used as a fertilizer or as a source of biogas for green energy applications, but the study, led by scientists at Scotland’s Rural College (SRUC) in collaboration with the universities of Bristol and Edinburgh, reviewed recent research into the development of high-value manure-derived materials from ruminant animals such as cattle.

They found that dung has been largely overlooked despite the variety of different applications for recycled ruminant waste biomass (RWB).

The most common applications use manure in combination with other components to create composite materials such as plastic, recycled card and paper or concrete. However, it could also be used for the extraction of nanocellulose - a prospective bio-based and biodegradable material of the future.

Currently, there is a trade-off between the performance of the material and the amount of processing required to achieve this – limiting the capacity of RWB to replace conventional materials on a commercial level.

Invasive Grass in Texas Uses Chemical Warfare to Crowd Out Native Species

Photo Credit: Courtesy of University of Texas at Austin

An invasive grass causing havoc in Texas and contributing to wildfires packs a one-two wallop against native plants. Guinea grass uses a combination of crowding that blocks out light from growing seedlings and what amounts to a chemical warfare in soil that is toxic to native plants, according to a new study by researchers at The University of Texas at Austin.

The findings are published in the journal Ecosphere.

Guinea grass is one of the most ecologically damaging invasive species in the world, arriving in South Texas from Africa more than 100 years ago, to help feed cattle. In the past 20 years, it has spread aggressively across the region and can now be found along roadsides as far north as Austin, bringing with it the risk of more frequent, high-intensity wildfires.

The researchers said knowing about how an invasive species takes over an area is an important step in figuring out how to control and reduce it in the environment.

“The shading and the chemical toxins are each effective at pushing out native plants on their own, but combined, the negative effects increased dramatically,” said Colin Morrison, a graduate student in the Department of Integrative Biology who is the lead author on the paper.

Berkeley researchers present plan for freshwater conservation

Study authors say freshwater conservation priorities should include connectivity, watershed disturbance, flow alteration, water quality, and biodiversity.
(A) Briones Dam reduces connectivity in Bear Creek, California.
(B) Wildfire in Hopland, California, creates widespread watershed disturbance.
(C) poor water quality in Porter Creek, California, kills fish and reduces recreational opportunities.
(D) freshwater ecosystems support biodiversity in Klamath Lake, Oregon.
Photo Credits: (A) L Andrews, (B) P Parker Shames, (C) G Rossi, (D) J Shames

The 30x30 initiative is a global effort to set aside 30% of land and sea area for conservation by 2030, a move scientists hope will reverse biodiversity loss and mitigate the effects of climate change. Now adopted by state and national governments around the world, 30x30 creates an unprecedented opportunity to advance global conservation.

When it comes to the water side of 30x30, most programs focus primarily on conservation of oceans, but a new study by researchers at the University of California, Berkeley argues that freshwater ecosystems must not be neglected. Published today in the journal Frontiers in Ecology and the Environment, the paper urges policy makers to explicitly include freshwater ecosystems like rivers, lakes, and wetlands in 30x30 plans, and outlines how their conservation will be critical to achieving the initiative’s broader goals. 

Stress memory in plants could hold key to growing disease resistant crops

Scientists at the University of Sheffield have discovered a mechanism behind how plants can acquire long-lasting resistance against attacks from insects
Illustration Credit: Courtesy of The University of Sheffield

A mechanism behind how plants can develop long-term immunity to stress has been discovered by scientists at the University of Sheffield.

Biotic stress experienced by plants can take the form of attacks by insect herbivores or disease-causing pathogens. In crops grown for food production, this stress provides a substantial risk to crop yields and is currently managed with the widespread use of pesticides, which are damaging for the environment and can pose a risk to human health.

Due to the urgent need to find better and more sustainable plant protection methods, Professor Jurriaan Ton, from the University of Sheffield’s Institute for Sustainable Food, and his team, investigated how plants are able to acquire long-lasting immunity against these stressors.

The findings, published in Nature Plants, explain a mechanism of how plants ‘remember’ the stress from a previous attack, and that this long-term memory is encoded in a family of 'junk DNA’ that can prime defense genes for several weeks against further attacks.

Does current shellfish culture gear curb ‘crunching’ rays?

Whitespotted eagle rays “crunching” on clams in a large outdoor tank with clams housed within a variety of anti-predator materials.

Video Credit: Florida Atlantic University / Harbor Branch Oceanographic Institute 

According to NOAA Fisheries, more than 80 percent of marine aquaculture production in the United States consists of bivalve mollusks such as oysters, clams and mussels. However, it’s not just humans who enjoy eating these shellfish, so do marine rays. They like to “crunch” on clams, which can sometimes take a big bite out of clammers’ profits.

Part of the process of culturing hard clams (Mercenaria mercenaria) involves deploying them in submerged bottom leases in the marine environment where clams can grow to market size. When deployed onto the clam lease, clammers incorporate a variety of anti-predator materials to protect their product, such as woven mesh netting and/or additional mesh, plastic or wire covers.

However, the effectiveness of these materials against highly mobile predators like rays has not been experimentally tested. Some rays, like the whitespotted eagle ray (Aetobatus narinari), are equipped with strong jaws, plate-like teeth and nimble pectoral fins, which make them formidable and highly maneuverable predators of clams.

Plastic containers can contain PFAS — and it’s getting into food

Illustration Credit: University of Notre Dame

Researchers at the University of Notre Dame are adding to their list of consumer products that contain PFAS (per- and polyfluoroalkyl substances), a toxic class of fluorine compounds known as “forever chemicals.”

In a new study published in Environmental Science and Technology Letters, fluorinated high-density polyethylene (HDPE) plastic containers — used for household cleaners, pesticides, personal care products and, potentially, food packaging — tested positive for PFAS. Following a report conducted by the EPA that demonstrated this type of container contributed high levels of PFAS to a pesticide, this research demonstrates the first measurement of the ability of PFAS to leach from the containers into food as well as the effect of temperature on the leaching process.

Results also showed the PFAS were capable of migrating from the fluorinated containers into food, resulting in a direct route of significant exposure to the hazardous chemicals, which have been linked to several health issues including prostate, kidney and testicular cancers, low birth weight, immunotoxicity and thyroid disease.

“Not only did we measure significant concentrations of PFAS in these containers, we can estimate the PFAS that were leaching off creating a direct path of exposure,” said Graham Peaslee, professor of physics in the Department of Physics and Astronomy at Notre Dame and an author of the study.