New discoveries on the containment of COVID-19 finds travel bans are of limited value

NYU Tandon researchers join collaboration with Politecnico di Torino revealing that after spread, travel bans are of limited value in thwarting the spread of COVID-19

NYU TANDON SCHOOL OF ENGINEERING

Research News

 

BROOKLYN, New York, Wednesday, February 24, 2021 - Travel bans have been key to efforts by many countries to control the spread of COVID-19. But new research aimed at providing a decision support system to Italian policy makers, recently published in the Journal of the Royal Society Interface, suggests that reducing individual activity (i.e., social distancing, closure of non-essential business, etc.) is far superior in controlling the dissemination of Sars-CoV-2, the virus that causes COVID-19.

The research, which has implications for the United States and other countries, found that limiting personal mobility through travel restrictions and similar tactics is effective only in the first phases of the epidemic, and reduces in proportion to the spread of infection across a population.

In the study, "Modelling and predicting the effect of social distancing and travel restrictions on COVID-19 spreading" the researchers, led by Alessandro Rizzo, visiting professor in the Office of Innovation at NYU Tandon and professor at the Politecnico di Torino, and Maurizio Porfiri Institute Professor of mechanical and aerospace, biomedical and civil and urban engineering at NYU Tandon and a member of the Center for Urban Science and Progress (CUSP), detail a data modeling framework for isolating the differential efficacy of different COVID-19 intervention policies. Since their method benefits from a low computational load (it can easily run on a personal computer), it can be a valuable decision support system to policy makers, toward the implementation of combined containment actions that can protect citizens' health, while avoiding total closures, with all their economic, social, and psychological consequences.

"While this project was focused specifically on Italy, the results are revelatory for virtually any country relying on travel restrictions to stem the spread of the pandemic. We look forward to using US data to tune the model and give specific answers to combat this delicate phase of the pandemic," said Porfiri.

Added Rizzo, "We are particularly satisfied with this model, as it provides very detailed answers even though it relies only on aggregated sources of data - a further guarantee of people's privacy."

The work includes a realistic representation of demographic data and travel patterns of both commuters and those taking long-distance trips, using only aggregated and publicly available data, without resorting to individual tracking devices. It follows upon a study on the spread of Covid-19 in New Rochelle, New York predicting the diffusion of COVID-19 in medium sized cities and provinces, published as the cover of Advanced Modeling and Simulations (Wiley),

The investigators, including Francesco Parino of Politecnico di Torino and Lorenzo Zino of the University of Groningen, The Netherlands, also found that selective lockdown policies, for example restriction only on the activity of the elderly, seems not to have a great effect on the overall transmission of the epidemic.

Deploying their algorithmic framework to model scenarios in which restrictions are lifted, discovered that restrictions on social activity must be gradually removed to avoid a second wave, while the timing and swiftness of removal of travel restrictions seem not to have a great effect on the transmission.

In view of the scarce resources and the inherent slowness of vaccination campaigns, the research group is now engaged in the use of the model to assess the effect of different vaccination policies, toward the definition of vaccination rollouts that will aim at providing an optimal outcome in spite of the limited resources in terms of vaccine doses and operators.

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The U.S. National Science Foundation (CMMI-1561134 and CMMI-2027990), Compagnia di San Paolo, MAECI ('Mac2Mic'), the European Research Council (ERC-CoG-771687), and The Netherlands Organisation for Scientific Research (NWO-vidi-14134) provided generous support for this research.

About the New York University Tandon School of Engineering

The NYU Tandon School of Engineering dates to 1854, the founding date for both the New York University School of Civil Engineering and Architecture and the Brooklyn Collegiate and Polytechnic Institute. A January 2014 merger created a comprehensive school of education and research in engineering and applied sciences as part of a global university, with close connections to engineering programs at NYU Abu Dhabi and NYU Shanghai. NYU Tandon is rooted in a vibrant tradition of entrepreneurship, intellectual curiosity, and innovative solutions to humanity's most pressing global challenges. Research at Tandon focuses on vital intersections between communications/IT, cybersecurity, and data science/AI/robotics systems and tools and critical areas of society that they influence, including emerging media, health, sustainability, and urban living. We believe diversity is integral to excellence, and are creating a vibrant, inclusive, and equitable environment for all of our students, faculty and staff. For more information, visit engineering.nyu.edu.

After Hurricane Irma, soundscape reveals resilient reef ecosystem

NORTH CAROLINA STATE UNIVERSITY

Research News

 

A new study from North Carolina State University reveals that the soundscapes of coral reef ecosystems can recover quickly from severe weather events such as hurricanes. The work also demonstrates that non-invasive monitoring is an important tool in shedding further light on these key ecosystems.

Soundscape ecology is a relatively new way for researchers to keep tabs on a variety of habitats without direct interference. In underwater habitats like coral reefs, soundscapes allow continual monitoring of an ecosystem that is difficult to access. By deploying underwater microphones, or hydrophones, researchers can get an acoustic picture of the types of animals in the ecosystem, as well as their behavior patterns.

Kayelyn Simmons, a Ph.D. student at NC State, used soundscapes and underwater mapping to monitor two different reef sites in the Florida Keys from February to December 2017. She deployed and collected eight hydrophones every three months between the two sites: a pristine reef located at Eastern Sambo, and a fishing site located at Western Dry Rocks.

Hurricane Irma struck the Florida Keys as a Category 4 storm in September 2017. Simmons was able to retrieve two of the hydrophones - one from each site - in December. Unfortunately, the hydrophone retrieved from Western Dry Rocks had been compromised by the storm, rendering its post-storm data unusable.

"Prior to the hurricane, we were able to determine what the 'normal' sound patterns were in each habitat, so we knew what the baselines were in terms of species and behavior," Simmons says. "You can tell which species are present based on where their sounds are on the frequency band. Similarly, the amount of noise from each species can give you an idea of their numbers. So the soundscape is a good way to measure abundance and diversity."

Each study site had the same species present. For example, snapping shrimp, with their high frequency "Rice Krispies in milk" popping noises, were active in the periods between dusk and dawn; while grunts, grouper and snapper, with sounds in the lower frequency bands, were mainly active during the day. The hydrophones also captured spawning activity during the full moon.

Simmons analyzed the sound captured by the surviving Eastern Sambo hydrophone and discovered that even though the reef suffered physical damage from the hurricane, the residents and their activity levels began returning to normal approximately 24 to 48 hours after the storm passed.

"The acoustic energy exposure for the reef was as loud as a small boat circling in one spot for two weeks," Simmons says. "So we didn't record any fish noises during the four-day period that Irma came through due to acoustic masking from the storm. However, the snapping shrimp were back to pre-storm sound levels within 24 hours. The fish noises on the lower frequency were back within 72. And on the next full moon we heard normal spawning behavior.

"Overall, the research shows that the coral reef soundscape was resilient and able to recover from the storm quickly."

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The work appears in PLOS One and was supported by the Coral Reef Conservation Fund (grant NA18NOS4820113) and the National Oceanic and Atmospheric Administration's National Marine Sanctuary Program (grant NFFM7320-19-01243). David Eggleston and Del Bohnenstiehl, both professors of marine, earth and atmospheric sciences at NC State, co-authored the work.

Note to editors: An abstract follows.

"Hurricane impacts on a coral reef soundscape"

DOI: 10.1371/journal.pone.0244599

Authors: Kayelyn Simmons, Dave Eggleston, Del Bohnenstiehl, North Carolina State University

Published: Feb. 24 in PLOS One

Abstract:

Soundscape ecology is an emerging field in both terrestrial and aquatic ecosystems, and provides a powerful approach for assessing habitat quality and the ecological response of sound producing species to natural and anthropogenic perturbations. Little is known of how underwater soundscapes respond during and after severe episodic disturbances, such as hurricanes. This study addresses the impacts of Hurricane Irma on the coral reef soundscape at two spur-and groove fore-reef sites within the Florida Keys USA, using passive acoustic data collected before and during the storm at Western Dry Rocks (WDR) and before, during and after the storm at Eastern Sambo (ESB). As the storm passed, the cumulative acoustic exposure near the seabed at these sites was comparable to a small vessel operating continuously overhead for 1-2 weeks. Before the storm, sound pressure levels (SPLs) showed a distinct pattern of low frequency diel variation and increased high frequency sound during crepuscular periods. The low frequency band was partitioned in two groups representative of soniferous reef fish, whereas the high frequency band represented snapping shrimp sound production. Daily daytime patterns in low frequency sound production largely persisted in the weeks following the hurricane. Crepuscular sound production by snapping shrimp was maintained post-hurricane with only a small shift (~1.5dB) in the level of daytime vs nighttime sound production for this high frequency band. This study suggests that on short time scales, temporal patterns in the coral reef soundscape were relatively resilient to acoustic energy exposure during the storm, as well as changes in the benthic habitat and environmental conditions resulting from hurricane damage.

Parker Solar Probe offers stunning view of Venus

NASA/GODDARD SPACE FLIGHT CENTER

Research News

 

IMAGE: WHEN FLYING PAST VENUS IN JULY 2020, PARKER SOLAR PROBE'S WISPR INSTRUMENT, SHORT FOR WIDE-FIELD IMAGER FOR PARKER SOLAR PROBE, DETECTED A BRIGHT RIM AROUND THE EDGE OF THE PLANET... view more 

CREDIT: NASA/JOHNS HOPKINS APL/NAVAL RESEARCH LABORATORY/GUILLERMO STENBORG AND BRENDAN GALLAGHER

NASA's Parker Solar Probe captured stunning views of Venus during its close flyby of the planet in July 2020.

Though Parker Solar Probe's focus is the Sun, Venus plays a critical role in the mission: The spacecraft whips by Venus a total of seven times over the course of its seven-year mission, using the planet's gravity to bend the spacecraft's orbit. These Venus gravity assists allow Parker Solar Probe to fly closer and closer to the Sun on its mission to study the dynamics of the solar wind close to its source.

But -- along with the orbital dynamics -- these passes can also yield some unique and even unexpected views of the inner solar system. During the mission's third Venus gravity assist on July 11, 2020, the onboard Wide-field Imager for Parker Solar Probe, or WISPR, captured a striking image of the planet's nightside from 7,693 miles away.

WISPR is designed to take images of the solar corona and inner heliosphere in visible light, as well as images of the solar wind and its structures as they approach and fly by the spacecraft. At Venus, the camera detected a bright rim around the edge of the planet that may be nightglow -- light emitted by oxygen atoms high in the atmosphere that recombine into molecules in the nightside. The prominent dark feature in the center of the image is Aphrodite Terra, the largest highland region on the Venusian surface. The feature appears dark because of its lower temperature, about 85 degrees Fahrenheit (30 degrees Celsius) cooler than its surroundings.

That aspect of the image took the team by surprise, said Angelos Vourlidas, the WISPR project scientist from the Johns Hopkins Applied Physics Laboratory (APL) in Laurel, Maryland, who coordinated a WISPR imaging campaign with Japan's Venus-orbiting Akatsuki mission. "WISPR is tailored and tested for visible light observations. We expected to see clouds, but the camera peered right through to the surface."

"WISPR effectively captured the thermal emission of the Venusian surface," said Brian Wood, an astrophysicist and WISPR team member from the U.S. Naval Research Laboratory in Washington, D.C. "It's very similar to images acquired by the Akatsuki spacecraft at near-infrared wavelengths."

This surprising observation sent the WISPR team back to the lab to measure the instrument's sensitivity to infrared light. If WISPR can indeed pick up near-infrared wavelengths of light, the unforeseen capability would provide new opportunities to study dust around the Sun and in the inner solar system. If it can't pick up extra infrared wavelengths, then these images -- showing signatures of features on Venus' surface -- may have revealed a previously unknown "window" through the Venusian atmosphere.

"Either way," Vourlidas said, "some exciting science opportunities await us."

For more insight into the July 2020 images, the WISPR team planned a set of similar observations of the Venusian nightside during Parker Solar Probe's latest Venus flyby on Feb. 20, 2021. Mission team scientists expect to receive and process that data for analysis by the end of April.

"We are really looking forward to these new images," said Javier Peralta, a planetary scientist from the Akatsuki team, who first suggested a Parker Solar Probe campaign with Akatsuki, which has been in orbiting Venus since 2015. "If WISPR can sense the thermal emission from the surface of Venus and nightglow -- most likely from oxygen -- at the limb of the planet, it can make valuable contributions to studies of the Venusian surface."

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Parker Solar Probe is part of NASA's Living with a Star program to explore aspects of the Sun-Earth system that directly affect life and society. The Living with a Star program is managed by the agency's Goddard Space Flight Center in Greenbelt, Maryland, for NASA's Science Mission Directorate in Washington. Johns Hopkins APL designed, built and operates the spacecraft.

CAPTION

NASA's Parker Solar Probe had an up-close view of Venus when it flew by the planet in July 2020. Some of the features seen by scientists are labeled in this annotated image. The dark spot appearing on the lower portion of Venus is an artifact from the WISPR instrument.

CREDIT

NASA/Johns Hopkins APL/Naval Research Laboratory/Guillermo Stenborg and Brendan Gallagher

Scientists link star-shredding event to origins of universe's highest-energy particles

NEW YORK UNIVERSITY

 VIDEO: AS THE STAR APPROACHES THE BLACK HOLE, THE ENORMOUS TIDAL FORCES STRETCH IT MORE AND MORE UNTIL IT IS FINALLY SHRED. HALF OF THE STELLAR DEBRIS IS FLUNG BACK INTO... view more 

CREDIT: DESY, SCIENCE COMMUNICATION LAB

A team of scientists has detected the presence of a high-energy neutrino--a particularly elusive particle--in the wake of a star's destruction as it is consumed by a black hole. This discovery, reported in the journal Nature Astronomy, sheds new light on the origins of Ultrahigh Energy Cosmic Rays--the highest energy particles in the Universe.

The work, which included researchers from more than two dozen institutions, including New York University and Germany's DESY research center, focused on neutrinos--subatomic particles that are produced on Earth only in powerful accelerators.

Neutrinos--as well as the process of their creation--are hard to detect, making their discovery, along with that of Ultrahigh Energy Cosmic Rays (UHECRs), noteworthy.

"The origin of cosmic high-energy neutrinos is unknown, primarily because they are notoriously hard to pin down," explains Sjoert van Velzen, one of the paper's lead authors and a postdoctoral fellow in NYU's Department of Physics at the time of the discovery. "This result would be only the second time high-energy neutrinos have been traced back to their source."

Previous research by van Velzen, now at the Netherlands' Leiden University, and NYU physicist Glennys Farrar, a co-author of the new Nature Astronomy paper, found some of the earliest evidence of black holes destroying stars in what are now known as Tidal Disruption Events (TDEs). These findings set the stage for determining if TDEs could be responsible for producing UHECRs.

The research reported in Nature Astronomy offered support for this conclusion.

Previously, the IceCube Neutrino Observatory, a National Science Foundation-backed detector located in the South Pole, reported the detection of a neutrino, whose path was later traced by the Zwicky Transient Facility at Caltech's Palomar Observatory.

Specifically, its measurements showed a spatial coincidence of a high-energy neutrino and light emitted after a TDE--a star consumed by a black hole.

"This suggests these star shredding events are powerful enough to accelerate high-energy particles," van Velzen explains.

"Discovering neutrinos associated with TDEs is a breakthrough in understanding the origin of the high-energy astrophysical neutrinos identified by the IceCube detector at the South Pole whose sources have so far been elusive," adds Farrar, who proposed in a 2009 paper that UHECRs could be accelerated in TDEs. "The neutrino-TDE coincidence also sheds light on a decades old problem: the origin of Ultrahigh Energy Cosmic Rays."

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The research was supported by grants from the National Science Foundation (CAREER grant 1454816, AAG grant 1616566, PIRE Grant 1545949, NSF grant AST-1518052)

DOI: 10.1038/s41550-020-01295-8

CAPTION

After the supermassive black hole tore the star apart, roughly half of the star debris was flung back out into space, while the remainder formed a glowing accretion disc around the black hole. The system shone brightly across many wavelengths and is thought to have produced energetic, jet-like outflows perpendicular to the accretion disc. A central, powerful engine near the accretion disc spewed out these fast subatomic particles.

CREDIT

DESY, Science Communication Lab

CAPTION

A view of the accretion disc around the supermassive black hole, with jet-like structures flowing away from the disc. The extreme mass of the black hole bends spacetime, allowing the far side of the accretion disc to be seen as an image above and below the black hole.

CREDIT

DESY, Science Communication Lab

Allergy season starts earlier each year due to climate change and pollen transport

Scientists in Munich study how pollen from far distances -- sometimes hundreds of kilometers away -- affects the length of allergy seasons in Germany

FRONTIERS

Research News

 

IMAGE: GRASS POLLEN GRAINS UNDER LIGHT MICROSCOPE view more 

CREDIT: A. MENZEL AND Y. YUAN, TECHNICAL UNIVERSITY OF MUNICH

Allergy sufferers are no strangers to problems with pollen. But now - due to climate change - the pollen season is lasting longer and starting earlier than ever before, meaning more days of itchy eyes and runny noses. Warmer temperatures cause flowers to bloom earlier, while higher CO2 levels cause more pollen to be produced.

The effects of climate change on the pollen season have been studied at-length, and according to some scientists, has grown by as much as 20 days in the past 30 years, at least in the US and Canada. But one important element is often overlooked - "Pollen is meant to fly," says Dr Annette Menzel, Professor of ecoclimatology at the Technical University of Munich. "Transport phenomena have to be taken into account."

Along with her colleagues, she studied the transport of pollen in Bavaria, Germany, in order to better understand how the pollen season has changed over time. "The transport of pollen has important implications for the length, timing, and severity of the allergenic pollen season," says Dr Ye Yuan, a coauthor on the study.

Menzel and her team focused on Bavaria - a state in southeast Germany - and used six pollen monitoring stations scattered around the region to analyze data. Their results were recently published in Frontiers in Allergy. They found that certain species of pollen, such as from hazel shrubs and alder trees, advanced the start of their seasons by up to 2 days per year, over a period of 30 years (between 1987 and 2017). Other species, which tend to bloom later in the year, such as birch and ash trees, moved their seasons 0.5 days earlier on average each year, across that same time period.

Pollen can travel hundreds of kilometers and, with changing weather patterns and altered species distributions, it's possible that people are becoming exposed to "new" pollen species - meaning pollen that our bodies are unaccustomed to encountering each year.

While it can sometimes be difficult to differentiate between local and transported pollen, the researchers focused on pre-season transports. So, for example, if pollen from birch trees was present at the monitoring station, but local birch trees would not flower for at least another 10 days, that pollen was considered to be transported from far away.

"We were surprised that pre-season pollen transport is a quite common phenomenon being observed in two-thirds of the cases," says Menzel. As for why it's important to understand how much pollen is from far away, Yuan says that: "Especially for light-weight allergenic [pollen], long distance transport could seriously influence local human health."

By examining another element besides simple pollen concentration, scientists can delve deeper into how exactly the pollen season is being affected by climate change. For example, Menzel says that the pollen season may be even longer than estimated based on flowering observations by "taking into account pollen transport, as it has been done in our current study."

While the Munich study did not track how far pollen was transported, and only differentiated between local and long-range transport (meaning pollen coming from outside Bavaria), it provides a crucial key in our understanding of annual pollen patterns. Yuan says that future studies should account for "climate change scenarios [and] land use/land cover changes." He also adds that citizen scientists may be able to contribute to pollen studies, who can help collect local observations and contribute to data collection.

It doesn't look like the pollen season will shorten any time soon, but more research on the subject can provide a better understanding of global patterns and changes so that we can better address these issues in the future.

CAPTION

Trap for measuring abundances of windborne pollen

CREDIT

A. Menzel and Y. Yuan, Technical University of Munich

The Tubes - Hoods From Outer Space 

(full album)

•Sep 26, 2016
The Tubes - Hoods From Outer Space

 1. Hoods From Outer Space 0:00​

 2. I Know You 4:08​ 

3. Say What You Want 8:00​

4. Around The World 12:10​ 

5. Genius Of America 16:34​ 

6. Who Names The Hurricanes 20:45​ 

7. It's Too Late 25:34​ 

8. How Can You Live With Yourself 28:25​

 9. I Never Saw It Comin" 33:39​ 

10. Arms Of The Enemy 36:58

​ 11. Fishhouse 41:34​ 

12. Big Brother"s Still Watching 46:12​ 

13. Fastest Gun Alive 51:06​ 

14. After All You Said 56:08

 WHITE JUNKIES

Study shows opioid use among US patients with knee osteoarthritis costs 14 billion dollars in societal costs

WILEY

Research News

 

Although guidelines do not recommend use of opioids to manage pain for individuals with knee osteoarthritis, a recent study published early online in Arthritis Care & Research, an official journal of the American College of Rheumatology and the Association of Rheumatology Professionals, estimates that 858,000 Americans use opioids such as tramadol and oxycodone for their knee pain, equating to $14 billion in lifetime opioid-related societal costs, or nearly $0.5 billion annually.

A team led by Elena Losina, PhD, Robert W. Lovett Professor of Orthopedic Surgery, of Brigham and Women's Hospital, used a computer simulation to estimate the annual and lifetime contribution of opioids to knee osteoarthritis-related costs. The researchers show the direct medical cost of knee osteoarthritis treatment including opioids totals $7.45 billion or 53 percent of the total lifetime costs. The remaining 47 percent of lifetime costs to society is used to pay for lost productivity at work, criminal justice expenses due to opioid use disorders among patients with knee osteoarthritis and cost associated with diversion activities related to illicit use by others.

For an individual patient who used opioids to treat their knee osteoarthritis, the lifetime opioid-related cost was estimated at $13,770. "Given larger number of patients with knee osteoarthritis using opioids, our results provide additional evidence of the substantial economic burden of opioid use for knee osteoarthritis pain management and the potential savings from preventing opioid use," said Dr. Losina.

The results reveal a substantial economic burden of opioid use among patients with knee osteoarthritis, and they indicate that substantial savings can result from following current guidelines recommending against such use.

"The most important part of our study is that we estimated that almost half of the total societal cost of opioid use in persons with symptomatic knee osteoarthritis is used to pay for lost work productivity and criminal justice and other consequences of the diversion of prescribed opiates to unlawful use," concludes Dr. Losina. "These data offer new evidence of the magnitude of the societal burden generated by opioid use and misuse and could be used to educate health care providers and health policy decision makers on the best alternatives to opiate use."

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Additional Information

NOTE: The information contained in this release is protected by copyright. Please include journal attribution in all coverage. For more information or to obtain a PDF of any study, please contact:

Dawn Peters +1 781-388-8408 (US)
newsroom@wiley.com

Follow us on Twitter @WileyNews

Full Citation: "Societal cost of opioid use in symptomatic knee osteoarthritis patients in the United States." Jamie L. Huizinga, Elizabeth E. Stanley, James K. Sullivan, Shuang Song, David J. Hunter, A. David Paltiel, Tuhina Neogi, Robert R. Edwards, Jeffrey N. Katz, and Elena Losina. Arthritis Care & Research; Published Online: February 25, 2021 (DOI: 10.1002/acr.24581).

URL Upon Publication: http://doi.wiley.com/10.1002/acr.24581

Author Contact: Haley Bridger, of the Brigham and Women's Media Relations Office, at hbridger@bwh.harvard.edu or +1 617-525-6383.

About the Journal

Arthritis Care & Research is an official journal of the American College of Rheumatology (ACR) and the Association of Rheumatology Professionals (ARP), a division of the College. Arthritis Care & Research is a peer-reviewed journal that publishes both original research and review articles that promote excellence in the clinical practice of rheumatology. Relevant to the care of individuals with arthritis and related disorders, major topics are evidence-based practice studies, clinical problems, practice guidelines, health care economics, health care policy, educational, social, and public health issues, and future trends in rheumatology practice. The journal is published by >

Wiley on behalf of the ACR. For more information, please visit the journal home page at http://wileyonlinelibrary.com/journal/acr.

On the line: Watching nanoparticles get in shape

New method could advance next-generation applications in medicine, cosmetics, and petroleum recovery

DOE/LAWRENCE BERKELEY NATIONAL LABORATORY

Research News

VIDEO: IMAGING OF THE SAME SPOT SHOWS THAT CRACKS EVENTUALLY SELF-HEAL, AN IMPORTANT TRADEMARK THAT MAINTAINS THE INTEGRITY OF STRUCTURED LIQUIDS. REAL-TIME VIDEO OF 70 NM NANOPARTICLES (RED) AND 500 NANOMETER... view more 

CREDIT: PAUL ASHBY AND TOM RUSSELL/BERKELEY LAB AND SCIENCE ADVANCES

Liquid structures - liquid droplets that maintain a specific shape - are useful for a variety of applications, from food processing to cosmetics, medicine, and even petroleum extraction, but researchers have yet to tap into these exciting new materials' full potential because not much is known about how they form.

Now, a research team led by Berkeley Lab has captured real-time high-resolution videos of liquid structures taking shape as nanoparticle surfactants (NPSs) - soap-like particles just billionths of a meter in size - jam tightly together, side by side, to form a solid-like layer at the interface between oil and water.

Their findings, recently featured on the cover of Science Advances , could help researchers better optimize liquid structures to advance new biomedical applications such as reconfigurable microfluidics for drug discovery and all-liquid robotics for targeted cancer drug delivery, among others.

In experiments led by co-author Paul Ashby , a staff scientist in Berkeley Lab's Molecular Foundry and Materials Sciences Division, and Yu Chai, a former postdoctoral researcher in the Ashby group who is now an assistant professor at The City University of Hong Kong, the researchers used a special imaging technique called atomic force microscopy (AFM) to take the first-ever real-time movies of the NPSs crowding together and getting jammed at the oil-water interface, a critical step in locking a liquid into a specific shape.

The researchers' movies unveiled a portrait of the NPS interface with unprecedented detail, including the size of each NPS, whether the interface was composed of one or multiple layers, and how much time elapsed, down to the second, for each NPS to attach to and settle into the interface.

The spectacular AFM images also showed the angle at which an NPS "sits" at the interface - an unexpected result. "We were surprised by how rough the interfaces are," Ashby said. "We had always drawn illustrations of a uniform interface with nanoparticles attached at the same contact angle - but in our current study, we found there is actually a lot of variation."

Most nanoscale imaging tools can only investigate immobile samples that are either dry or frozen. Over the past couple of decades, Ashby has focused his research on developing unique AFM capabilities that allow the user to control the probe tip so it gently interacts with fast-moving samples, such as the NPSs of the current study, without touching the underlying liquid - a challenging feat.

"Imaging a liquid structure at the nanoscale, and watching the nanoparticles move around in liquid in real time using an AFM probe - that wouldn't be possible without Paul's extensive expertise," said co-author Thomas Russell , a visiting faculty scientist and professor of polymer science and engineering from the University of Massachusetts who leads the Adaptive Interfacial Assemblies Towards Structuring Liquids program in Berkeley Lab's Materials Sciences Division. "These kinds of capabilities aren't available anywhere else except at the Molecular Foundry."

The researchers next plan to study the effect of self-propelling particles in NPS liquid structures.

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Ashby and Russell co-led the study. Researchers from Berkeley Lab; UC Berkeley; The City University of Hong Kong; Hong Kong Polytechnic University; Soochow University and Beijing University of Chemical Technology, China; and Tohoku University, Japan, contributed to the work.

The Molecular Foundry is a DOE Office of Science user facility at Berkeley Lab.

This work was supported by the U.S. Department of Energy Office of Science.

Founded in 1931 on the belief that the biggest scientific challenges are best addressed by teams, Lawrence Berkeley National Laboratory and its scientists have been recognized with 14 Nobel Prizes. Today, Berkeley Lab researchers develop sustainable energy and environmental solutions, create useful new materials, advance the frontiers of computing, and probe the mysteries of life, matter, and the universe. Scientists from around the world rely on the Lab's facilities for their own discovery science. Berkeley Lab is a multiprogram national laboratory, managed by the University of California for the U.S. Department of Energy's Office of Science.

DOE's Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit energy.gov/science.

Conservation paradox - the pros and cons of recreational hunting

Recreational hunting -- especially hunting of charismatic species for their trophies -- raises ethical and moral concerns

FLINDERS UNIVERSITY

Research News

 

IMAGE: LIONS IN THE WILD view more 

CREDIT: ASSOCIATE PROFESSOR ENRICO DI MININ, UNIVERSITY OF HELSINKI

Recreational hunting -- especially hunting of charismatic species for their trophies --raises ethical and moral concerns. Yet recreational hunting is frequently suggested as a way to conserve nature and support local people's livelihoods.

In a new article published in the journal One Earth, scientists from the University of Helsinki in Finland and Flinders University in Australia have reviewed more than 1,000 studies on recreational hunting -- the first such attempt to summarize the scientific literature examining the biodiversity and social effects of recreational hunting globally.

Co-lead author University of Helsinki Associate Professor Enrico Di Minin says while it might seem counterintuitive, there is evidence to suggest some recreational hunting can deliver environmental and social benefits.

University of Helsinki colleague and co-lead author Dr Hayley Clements says more analysis is needed to understand how and why recreational hunting can work for good, and those areas where it can be detrimental.

Flinders University Professor Corey Bradshaw says it's a paradox that goes to the heart of the pros and cons of recreational hunting.

"We determined the geographic spread and diversity of species hunted around the globe, and investigated and summarized the main topics surrounding recreational hunting to consider both the positive and negative implications of recreational hunting for nature conservation and the livelihoods and well-being of people" says Professor Bradshaw, who leads Flinders' Global Ecology Lab.

"On the one hand, recreational hunting can reduce the number of individual animals in a population, whereas on the other, diverting land from agricultural or other types of development to priority hunting areas can in fact benefit entire ecosystems", he says.

Hunting research has focused mainly on the behaviour and population dynamics of large mammals in North America, Europe and Africa.

Dr Clements says evidence is still lacking, however, to answer the pressing questions of why hunting contributes to sustainable conservation of biodiversity in some places and not others.

"Two-thirds of the hunting research is focussed on mammals. Red deer, white-tailed deer, wild boar, moose and lion are the most well-studied. Of these species, only the lion is of conservation concern, with many recommendations on how hunting can be made sustainable through quotas or seasonal limits", says Dr Clements.

"Far less research has tried to examine the broader impacts of hunting on ecosystem integrity and function, and how it affects the livelihoods of local people, or to document local people's perceptions about hunting", she continues.

For example, approximately 1,394,000 km2 of land is dedicated for trophy hunting in sub-Saharan Africa, yet there is little research on how effective these areas are in conserving ecosystems, and how local communities benefit from hunting.

Associate Professor Di Minin, who leads the Helsinki Lab of Interdisciplinary Conservation Science contends future research should focus on the contribution of recreational hunting towards meeting both biodiversity and social objectives.

"We have outlined a research agenda to assess the role of recreational hunting in diverse social-ecological systems, and to consider local people's values and needs.

The need for such evidence is urgent given declining numbers of recreational hunters in some regions and increasing opposition to trophy hunting in others", says Associate Professor Di Minin.

"We should also expand research beyond charismatic and common species to assess the impact of recreational hunting on threatened and less charismatic species", he concludes

CAPTION

Zebra in the wild

CREDIT

Associate Professor Enrico Di Minin, University Of Helsinki

Article reference:

Di Minin, Enrico; Clements, Hayley; Correia, Ricardo; Cortés-Capano, Gonzalo; Hausmann, Anna; Haukka, Anna; Kulkarni, Ritwik; Bradshaw, Corey J. A. Consequences of recreational hunting for biodiversity conservation and livelihoods. One Earth doi: 10.1016/j.oneear.2021.01.014.

A-maze-ing pheasants have two ways of navigating

UNIVERSITY OF EXETER

Research News

 

IMAGE: A MAZE USED IN THE STUDY (HERE WITH ALL DOORS/WALLS OPEN). view more 

CREDIT: PIP LAKER

Pheasants fall into two groups in terms of how they find their way around - and the different types prefer slightly different habitats, new research shows.

University of Exeter scientists tested whether individual pheasants used landmarks (allocentric) or their own position (egocentric) to learn the way through a maze.

The captive-bred pheasants were later released into the wild, and their choice of habitat was observed.

All pheasants favoured woodland, but allocentric navigators spent more time out in the open, where their landmark-based style is more useful.

"Humans tend to use both of these navigational tactics and quite frequently combine them, but when animals are tested, they often seem to rely more on one or the other," said Dr Christine Beardsworth.

"It is assumed that species favour whichever strategy suits their habitat, rather than using habitats which suit their strategy.

"Pheasants generally favour woodland, where an allocentric strategy is difficult because there are lots of trees close together, so it is hard to pick out landmarks.

"So, we might expect most pheasants to use an egocentric strategy - turning left, turning right or moving forward based on their own position and previous movements.

"However, in our study about half of pheasants reared in identical conditions used an allocentric strategy, while the other half used an egocentric or mixed strategy."

In the experiments, 20 pheasants first learned how to navigate through a simple maze, then faced a rotated version.

By altering the orientation of the maze but keeping the placement of "landmarks" the same, including the position of a human observer, the scientists were able to establish the preferred navigation strategy of each pheasant.

The discovery of individual variation suggest pheasants are either born with an "inherent cognitive bias", or develop one early in life.

Resulting differences in habitat selection may indicate that these biases help them to navigate more effectively in particular environments, perhaps outperforming other pheasants in relocating resources. However, it is not yet clear whether this is the case.

CAPTION

A juvenile pheasant

CREDIT

Pip Laker

The research team included the Hebrew University of Jerusalem and Tel-Aviv University.

The work was funded by an ERC consolidators grant awarded to Dr Joah Madden.

The paper, published in the journal Ecology Letters, is entitled: "Is habitat selection in the wild shaped by individual-level cognitive biases in orientation strategy?"