Long-term study of elephant seal reproduction shows population’s resilience

Researchers found that a female elephant seal’s age and experience were more important than ocean conditions in determining the condition of her pup at weaning

Peer-Reviewed Publication

UNIVERSITY OF CALIFORNIA - SANTA CRUZ

 

IMAGE: RESEARCHERS FOUND THAT AS THE DENSITY OF AN ELEPHANT SEAL BREEDING COLONY INCREASES, THE SIZE OF THE PUPS AT WEANING DECLINES, AND THIS EFFECT IS MORE PRONOUNCED FOR YOUNGER FEMALES. view more 

CREDIT: PHOTO BY DANIEL COSTA

A new study based on four decades of data from the elephant seal colony at Año Nuevo Reserve has enabled researchers to disentangle the effects of environmental conditions, population density, and maternal traits on reproductive success in northern elephant seals.

The study, published October 13 in Proceedings of the Royal Society B, focused on how much the pups weighed when they were weaned (weaning mass), because higher weaning mass increases a pup’s chance of survival. First author Rachel Holser, a postdoctoral researcher at UC Santa Cruz, said she expected major oceanographic events that affect the abundance and distribution of the seals’ prey to have a big effect. To her surprise, however, other factors turned out to be much more important.

“The single most important factor in determining the weaning mass of pups was the age of the mother,” Holser said. “That was more important than the mother’s size, which is a measure of her foraging success, and certainly more important than conditions in the ocean. We expected major El Niño events and other oceanographic events to have more impact than they did.”

The mother’s age is important for several reasons, she noted. One is that older females produce milk with higher fat content at the start of lactation than young females do. But the mother’s experience is also crucially important. A more experienced female is better able to choose and defend a good location on the beach for rearing her pup, and she is better able to keep her pup from getting lost and wasting its energy.

“When she gives birth to this tiny pup, it’s got four weeks to put on as much fat as it can, which means it needs to spend as much time as possible nursing and resting,” Holser said.

This gets harder as the population grows and more and more animals are crowded together on the beach. “When the colony becomes more dense, there are more interactions—sometimes the females are fighting, or the males will cause a disturbance—and pups end up getting lost and wasting energy trying to find their mother,” she said.

The study found that higher population densities led to smaller pups overall, but this effect was more pronounced for younger females than for the older, more experienced ones.

Holser noted that, while it is often assumed that a larger female will have larger pups, the mother’s age is actually more important than her size. “There’s a lot of variability in size, and the data show that what’s really important is the experience of having been through multiple reproductive cycles,” she said.

Ocean conditions—such as El Niño events, the Pacific Decadal Oscillation, and marine heatwaves—do matter, she said, but their effects on weaning mass are relatively small compared to other factors. “It’s not that it doesn’t play a role, but it’s not nearly as important as those onshore conditions—who your mother is and how dense the colony is,” Holser said.

This resilience in the face of changing environmental conditions is largely due to the elephant seals’ reproductive strategy. Female elephant seals spend months at sea traveling vast distances across the North Pacific Ocean to feed and put on weight before returning to the colony to give birth. While nursing their pup, they do not leave the beach to feed, relying on the stored energy acquired during the foraging migration.

Other species, such as the California sea lion, depend on regular feeding forays while they are nursing their pups, so a change in conditions that makes it harder to find prey off the coast can be disastrous.

“During a major El Niño, you can see almost complete reproductive failure in some years for species like sea lions,” Holser said. “With elephant seals, we don’t see that kind of boom and bust effect. Even in a poor year, they manage to be pretty successful.”

She cautioned, however, that the effects of ocean conditions on elephant seals can be seen in some measures of the population’s health other than weaning mass. In bad years, some females will skip breeding entirely to restore their body condition rather than rearing a pup. There may also be a decrease in the survival rate of adult females.

“Previous work has shown that ocean conditions impact the ability of the mother to invest in her young, but this study shows that age and, more importantly, experience can compensate for those environmental changes,” said coauthor Daniel Costa, professor of ecology and evolutionary biology and director of the Institute of Marine Sciences at UCSC. “As a senior scientist, it’s good to know that experience matters!”

Northern elephant seals were hunted to near extinction by the early 1900s, but the population has made a remarkable recovery since the end of commercial sealing. Thousands of pups are now born every year at the breeding colony at Año Nuevo Reserve, part of the UC Natural Reserve System.

The long-running elephant seal research program at UC Santa Cruz has been studying this colony since the 1960s, yielding an invaluable trove of data. Begun by Professor Emeritus Burney Le Boeuf, the program has continued under Costa’s leadership.

“This study was only possible because of the work of hundreds of people who have been taking these measurements for over 40 years,” Holser said.

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In addition to Holser and Costa, the coauthors of the paper include Daniel Crocker at Sonoma State University, Patrick Robinson at UC Santa Cruz, and Richard Condit at the Field Museum of Natural History in Chicago.

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JOURNAL

Proceedings of the Royal Society B Biological Sciences

DOI

10.1098/rspb.2021.1258 

METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

Density-dependent effects on reproductive output in a capital breeding carnivore, the northern elephant seal (Mirounga angustirostris)

ARTICLE PUBLICATION DATE

13-Oct-2021

COI STATEMENT

We declare we have no competing interests.

New galaxy images reveal a fitful start to the Universe

Peer-Reviewed Publication

UNIVERSITY OF NOTTINGHAM

 

IMAGE: IMAGE FROM SHARDS STUDY view more 

CREDIT: SHARDS RESEARCH TEAM

New images have revealed detailed clues about how the first stars and structures were  formed in the Universe and suggest the formation of the Galaxy got off to a fitful start. 

An international team of astronomers from the University of Nottingham and Centro de Astrobiología (CAB, CSIC-INTA) used data from the Hubble Space Telescope (HST) and the Gran Telescopio Canarias (GTC), the so-called Frontier Fields, to locate and study some of the smallest faintest galaxies in the nearby universe. This has revealed the formation of the galaxy was likely to be fitful. The first results have just been published in the journal Monthly Notices of the Royal Astronomical Society (MNRAS). 

One of the most interesting questions that astronomers have been trying to answer for decades is how and when the first galaxies formed. Concerning the how, one possibility is that the formation of the first stars within galaxies started at a steady pace, slowly building up a more and more massive system. Another possibility is that the formation was more violent and discontinuous, with intense, but short lived bursts of star formation triggered by events such as mergers and enhanced gas accretion.  

“Galaxy formation can be compared to a car”, explains Pablo G. Pérez-González, one of the co-authors of the paper, affiliated to the Centro de Astrobiología (CAB/CSIC-INTA) in Spain, and principal investigator of the international collaboration behind this study. “The first galaxies might have had a ‘diesel’ star-forming engine, slowly but continuously adding up new stars, without much acceleration and gently turning gas into relatively small stars for long periods of time. Or the formation could have been jerky, with bursts of star formation producing incredibly large stars that disrupt the galaxy and make it cease its activity for a while or even forever. Each scenario is linked to different processes, such as galaxy mergers or the influence of supermassive black holes, and they have an effect on when and how the carbon or oxygen, that are essential for our life, formed.” 

Using the gravitational lensing power of some of the Universe's most massive galaxy clusters with the exceptional GTC data coming from a project entitled the Survey for high-z Red and Dead Sources (SHARDS) the astronomers searched for nearby analogs of the very first galaxies formed in the Universe, so that they could be studied in much more detail.  

Dr Alex Griffiths from the University Nottingham was one of the lead UK researchers on the study, he explains: “Until we have the new James Webb Space telescope, we cannot observe the first galaxies ever formed, they are just too faint. So we looked for similar beasts in the nearby Universe and we dissected them with the most powerful telescopes we currently have.” 

The researchers combined the power of the most advanced telescopes, such as HST and GTC, with the aid of “natural telescopes”. Professor Chris Conselice, from the University of Manchester is a co-author on the study, he said: “Some galaxies live in large groups, what we call clusters, which contain huge amounts of mass in the form of stars, but also gas and dark matter. Their mass is so large that they bend space-time, and act as natural telescopes. We call them gravitational lenses and they allow us to see faint and distant galaxies with enhanced brightness and at a higher spatial resolution”.  

Observations of some of these massive clusters acting as gravitational telescopes is the base of the Frontier Field survey. The study showed that the formation of the galaxy was likely to be stop-start with bursts of activity followed by lulls. Dr Griffiths from the University of Nottingham said: “Our main result is that the start of galaxy formation is fitful, like a jerky car engine, with periods of enhanced star formation followed by sleepy intervals. It is unlikely that galaxy mergers have played a substantial role in the triggering of these bursts of star formation and it is more likely due to alternative causes that enhance gas accretion, we need to search for those alternatives. 

“We were able to find these objects due to the high quality SHARDS data coupled with imaging data from the Hubble Space Telescope to detect hot gas heated by newly formed stars in very small galaxies. This hot gas emits in certain wavelengths, what we call emission lines, just as a neon light. Analysing these emission lines can provide an insight into the formation and evolution of a galaxy.”.  

“The SHARDS Frontier Fields observations carried out with GTC have provided the deepest data ever taken for discovering dwarf galaxies through their  emission lines, allowing us to identify systems with recently triggered star formation”, adds Pérez-González, one of the co-authors of the paper and principal investigator of the GTC SHARDS Frontier Fields project. 

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JOURNAL

Monthly Notices of the Royal Astronomical Society

DOI

10.1093/mnras/stab2566 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Emission Line Galaxies in the SHARDS Frontier Fields I: Candidate Selection and the Discovery of Bursty Ha Emitters

ARTICLE PUBLICATION DATE

21-Oct-2021

Disclaimer: AAAS an

Some of the world’s oldest rubies linked to early life

Peer-Reviewed Publication

UNIVERSITY OF WATERLOO

 

IMAGE: PHOTO OF THE RUBY THAT THIS STUDY LOOKS AT view more 

CREDIT: UNIVERSITY OF WATERLOO

While analyzing some of the world’s oldest coloured gemstones, researchers from the University of Waterloo discovered carbon residue that was once ancient life, encased in a 2.5 billion-year-old ruby.

The research team, led by Chris Yakymchuk, professor of Earth and Environmental Sciences at Waterloo, set out to study the geology of rubies to better understand the conditions necessary for ruby formation. During this research in Greenland, which contains the oldest known deposits of rubies in the world, the team found a ruby sample that contained graphite, a mineral made of pure carbon. Analysis of this carbon indicates that it is a remnant of early life.

“The graphite inside this ruby is really unique. It’s the first time we’ve seen evidence of ancient life in ruby-bearing rocks,” says Yakymchuk. “The presence of graphite also gives us more clues to determine how rubies formed at this location, something that is impossible to do directly based on a ruby’s colour and chemical composition.”

The presence of the graphite allowed the researchers to analyze a property called isotopic composition of the carbon atoms, which measures the relative amounts of different carbon atoms. More than 98 per cent of all carbon atoms have a mass of 12 atomic mass units, but a few carbon atoms are heavier, with a mass of 13 or 14 atomic mass units.

“Living matter preferentially consists of the lighter carbon atoms because they take less energy to incorporate into cells,” said Yakymchuk. “Based on the increased amount of carbon-12 in this graphite, we concluded that the carbon atoms were once ancient life, most likely dead microorganisms such as cyanobacteria.”

The graphite is found in rocks older than 2.5 billion years ago, a time on the planet when oxygen was not abundant in the atmosphere, and life existed only in microorganisms and algae films.

During this study, Yakymchuk’s team discovered that this graphite not only links the gemstone to ancient life but was also likely necessary for this ruby to exist at all. The graphite changed the chemistry of the surrounding rocks to create favourable conditions for ruby growth. Without it, the team’s models showed that it would not have been possible to form rubies in this location.

The study, Corundum (ruby) growth during the final assembly of the Archean North Atlantic Craton, southern West Greenland, was recently published in Ore Geology Reviews. A companion study, The corundum conundrum: Constraining the compositions of fluids involved in ruby formation in metamorphic melanges of ultramafic and aluminous rocks, was published in the journal Chemical Geology in June.

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JOURNAL

Ore Geology Reviews

Research identifies new family of marine ‘megaphages’

Microbiologists have identified a new family of marine megaphages which could change understanding of Earth’s carbon and nitrogen cycles

Peer-Reviewed Publication

UNIVERSITY OF LEICESTER

 

IMAGE: RESEARCHERS DEPLOY SAMPLING EQUIPMENT IN PLYMOUTH SOUND. view more 

CREDIT: MARINE BIOLOGICAL ASSOCIATION

Microbiologists have identified a new family of marine megaphages which could change understanding of Earth’s carbon and nitrogen cycles.

Researchers from the Universities of Leicester, Warwick, Nottingham, Plymouth and the Marine Biological Association have sequenced the largest genome of its type within a newly-discovered family of ocean-dwelling bacteriophages, from water in the English Channel.

Bacteriophages – referred to in this instance as ‘megaphages’ due to the extreme size of their genomes – are viruses which prey on bacteria, and are the most abundant biological entities on Earth.

Following study of the predicted function of the genes, the researchers speculate that these megaphages could potentially alter the metabolism of their as-yet-unknown host in the marine environment.

Since ocean bacteria are known to play a major role in the cycling of carbon and nitrogen – 50% of the oxygen we breathe comes from the oceans via carbon fixation – these newly-identified megaphages are thought to potentially play an important role in this process.

Dr Andrew Millard, Associate Professor of Bacteriophage Bioinformatics at the University of Leicester and corresponding author for the study published in ISME Communications, said:

“From our previous work on cyanophages, we know phages have important roles in biogeochemical cycling. Finding these very large genomes with auxiliary metabolic genes, further highlights how phages may impact biogeochemical cycles.

“To understand the role of these megaphages, we now need to culture them to study them further.”

Researchers studied these new bacteriophages using a combination of Illumina and MinION sequencing. While the majority of known phages contain genomes smaller than 200 kb, one of these megaphages – dubbed Mar_Mega_1 – showed a genome of more than 650 kb in length, making it one of the largest phage genomes assembled to date. The largest known megaphage genome is 735 kb in length.

Using phylogenetic and genomic analyses, researchers showed Mar_Mega_1 is distantly related to other megaphages previously found in the guts of humans, and based on current standards, represents a new family of phages in the marine environment.

CAPTION

Researchers deploy sampling equipment in Plymouth Sound.

CREDIT

Marine Biological Association

MBA Sepia Sampling (IMAGE)

UNIVERSITY OF LEICESTER

CAPTION

Researchers deploy sampling equipment in Plymouth Sound.

CREDIT

Marine Biological Association

‘A new family of “megaphages” abundant in the marine environment’ is published in ISME Communications.

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JOURNAL

ISME Communications

DOI

10.1038/s43705-021-00064-6 

METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

Cells

ARTICLE TITLE

A new family of “megaphages” abundant in the marine environment

ARTICLE PUBLICATION DATE

21-Oct-2021

COI STATEMENT

The authors declare no competing interests

CAPTION

RV Sepia in Plymouth Sound.

CREDIT

Marine Biological Association

Spending time in nature promotes early childhood development

Peer-Reviewed Publication

UNIVERSITY OF BRITISH COLUMBIA

 

IMAGE: MAP DEPICTING THE ANNUAL PERCENTAGE OF GREENSPACE IN METRO VANCOUVER FOR 2011. DARKER SHADES OF GREEN DEPICT AREAS OF HIGHER VEGETATION PERCENTAGE, WHILE LIGHTER SHADES OF GREEN DEPICT AREAS OF LOWER VEGETATION PERCENTAGE. view more 

CREDIT: UBC

Want to ensure your child hits their expected developmental milestones? New UBC research suggests living in areas with high exposure to greenspace can help set them up for success.

For the study, researchers at the UBC faculty of forestry and faculty of medicine analyzed the developmental scores of 27,372 children in Metro Vancouver who attended kindergarten between 2005 and 2011. They estimated the amount of greenspace around each child’s residence from birth to age five. They also assessed levels of traffic-related air pollution and community noise.

The results highlight the fundamental importance of natural green spaces like street trees, parks and community gardens, authors say.

“Most of the children were doing well in their development, in terms of language skills, cognitive capacity, socialization and other outcomes,” says study author Ingrid Jarvis (she/her), a PhD candidate in the department of forest and conservation sciences at UBC. “But what’s interesting is that those children living in a residential location with more vegetation and richer natural environments showed better overall development than their peers with less greenspace.”

According to the researchers, the reason for this is partly greenspaces’ ability to reduce the harmful effects of air pollution and noise—environmental challenges that have been shown to adversely affect children’s health and development through increased stress, sleep disturbances and central nervous system damage.

“Few studies have investigated this pathway linking greenspace and developmental outcomes among children, and we believe this is the first Canadian study to do so,” adds Jarvis.

The researchers assessed early childhood development using the Early Development Instrument (EDI), a survey completed by kindergarten teachers for each child. The tool measures a child’s ability to meet age-appropriate developmental expectations.

“More research is needed, but our findings suggest that urban planning efforts to increase greenspace in residential neighbourhoods and around schools are beneficial for early childhood development, with potential health benefits throughout life,” says the study’s senior author and UBC research associate, Matilda van den Bosch (she/her).

“Time in nature can benefit everyone, but if we want our children to have a good head start, it’s important to provide an enriching environment through nature contact. Access to greenspace from a very young age can help ensure good social, emotional and mental development among children.”

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The study, published recently in The Lancet Planetary Health, includes contributions by researchers at the University of California Berkeley, University of California Los Angeles, Barcelona Institute for Global Health, BC Children’s Hospital and BC Centre for Disease Control.

Interview languages: English (Jarvis and van den Bosch)

Disclaimer: This work was supported by data made accessible via Population Data BC, the Canadian Urban Environmental Health Research Consortium, and the Integrated Remote Sensing Studio at the University of British Columbia. All inferences, opinions, and conclusions drawn in this study are those of the authors, and do not reflect the opinions or policies of the Data Steward(s).

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JOURNAL

The Lancet Planetary Health

DOI

10.1016/S2542-5196(21)00235-7 

METHOD OF RESEARCH

Data/statistical analysis

ARTICLE TITLE

Assessing the association between lifetime exposure to greenspace and early childhood development and the mediation effects of air pollution and noise in Canada: a population-based birth cohort study

ARTICLE PUBLICATION DATE

1-Oct-2021

Back pain common among astronauts offers treatment insights for the earth-bound

Research reviews show back pain affects more than 50% of space travelers

Peer-Reviewed Publication

JOHNS HOPKINS MEDICINE

 

IMAGE: SPINAL COLUMN ON EARTH AND IN SPACE. view more 

CREDIT: JOHNS HOPKINS MEDICINE

— As more people travel into space, Johns Hopkins Medicine experts expect more physicians will see patients with space travel-related pain.

— Although most back pain in space disappears on its own, space travelers are at higher risk for sciatica — a form of back pain that can radiate down the legs.

— Humans can “grow” up to 3 inches in space as the spine adapts to microgravity.

— Stress, trauma and changes in nutrition likely contribute to back pain developed during space travel.

With growing numbers of humans venturing into space, experts predict an increase in the number of people experiencing the physical toll of such travel, including highly common forms of back pain.

The prediction comes in a new report by researchers at Johns Hopkins Medicine, published in the September issue of Anesthesiology, based on a comprehensive review of past studies measuring the effects of space travel on the spine, and exploring methods to prevent, diagnose, and treat back pain. The scientists say further study among astronauts of these methods — including specialized suits and certain exercises — may provide insights for treating back pain in the estimated 80% of Earth-bound people who experience some form of it over their lifetimes.

Steven Cohen, M.D., professor of anesthesiology and critical care medicine at Johns Hopkins and a retired Army colonel. “Perhaps more importantly, insight into back pain in space travelers may provide usable information to treat back pain in other populations.”

An Aching Back: A Common Low Gravity-Related Pain

According to the review, past studies of astronauts have shown that 52% of space travelers report some form of back pain in the first two to five days of space travel. That figure is based on a retrospective study of 722 space flights worldwide published in Aerospace Medicine and Human Performance in 2012. The condition is now dubbed “space adaptation back pain,” and although 86% of cases were mild, the pain was enough to hinder an astronaut’s ability to complete tasks.

In addition to the studies among astronauts, a study from the University of Innsbruck in Austria showed that nearly half of military helicopter pilots and crewmembers who experience fluctuating gravitational forces report low back pain. The pilots are almost three times more likely to develop lumbar (lower back) disc herniation — an injury to the soft connective cushioning in the spine — compared with the general population. Astronauts are more than four times as likely to herniate a disc, according to a NASA study in 2010, and the risk was even higher in the first year after returning to Earth.

The Spine Changes in Space

Penchev says the high prevalence of back pain among these groups is understandable because the human spine is built to support our bodies under the gravitational forces experienced on Earth. One prominent feature is the spinal curvature — an S-shaped bend in the spine that allows it to resist gravity, remain flexible and absorb weight and impact. However, in microgravity, this curve is reduced. Some of the earliest data from space explorations, say the researchers, showed astronauts “grew” over 3 inches in space due to the loss of this curve. More recent studies using MRI scans showed modern-day astronauts have a reduced curve in their spine.

“If reduced gravity allows this curvature to straighten,” says Radostin Penchev, M.D., resident physician at The Johns Hopkins Hospital, “this not only could be a cause of acute pain in astronauts, but also could affect the stability of their spine when they return to earth.”

Preventing and Treating Astronauts’ Back Pain

In their review of past studies, the researchers said that along with microgravity’s stresses, other contributors to back pain in space include the intense physical experience of riding in a rocket and a change in dietary habits that could alter nutritional levels in the body and impact tissue health and healing.

Throughout the Space Age, the researchers say resistance exercises — such as isometrics, squats, lunges and bench pressing — have been a mainstay of back pain prevention, and space stations are equipped with exercise machines and other resistance training tools.

“Science fiction has popularized the spinning space station that uses centrifugal force to mimic gravity,” says Penchev. A more realistic and perhaps better alternative, he adds, are specialized suits that provide spinal resistance similar to that experienced under Earth’s gravity.

The experience is similar to donning rubber bands from the shoulders to hips to help activate the muscle groups that keep us standing upright on Earth, say the researchers. The Aerospace Medicine and Human Performance study of 722 space flights showed that the use of such a resistance suit along with exercise regimens relieved space-adaptation back pain in 85% of subjects. However, some astronauts complain these suits are uncomfortable and impair their range of motion.

Other methods to prevent back pain among astronauts mentioned by the researchers include massage, nutritional supplementation to increase vitamin D and caloric intake, neuromuscular electrical stimulation, and negative pressure devices, all paired with resistance exercise.

To combat the intense vibrations and speed of riding rockets into space, Cohen, Penchev and their team believe that engineering space vehicles to improve impact protection for the flight crew and align the forces of acceleration and impact with human anatomy could reduce the number of astronauts experiencing long-term back pain or injury.

Other researchers who authored the review include Richard Scheuring of the National Aeronautics and Space Administration Johnson Space Center; Adam Soto of the Uniformed Services University of the Health Sciences and the Tripler Army Medical Center; Derek Miletich of the Naval Medical Center – San Diego; and Eric Kerstman of the National Aeronautics and Space Administration Johnson Space Center and the University of Texas.

This work was supported by the departments of anesthesiology and physical medicine and rehabilitation at the Johns Hopkins University School of Medicine and the Uniformed Services University of the Health Sciences, and by the U.S. Department of Defense.

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JOURNAL

Anesthesiology

UCI researchers monitor SARS-CoV-2 using wastewater-based epidemiology

Novel coronavirus levels in wastewater correlate with regional patient data

Peer-Reviewed Publication

UNIVERSITY OF CALIFORNIA - IRVINE

Alternative viral detection methods have been critical in the fight against COVID-19, helping to reduce the burden on our healthcare system. In a new study published in Applied and Environmental Microbiology, University of California, Irvine researchers demonstrate the efficiency of wastewater-based epidemiology (WBE) to monitor the presence and genetic diversity of SARS-CoV-2 among other viruses in Southern California.

COVID-19 mitigation strategies require accurate and affordable detection methods to help minimize the spread of SARS-CoV-2. Clinical-based detection methods remain the gold standard; however, WBE, which represents the collective waste of the human population in a given locale, can detect viral pathogens and potentially serve as an early warning detection system during a viral outbreak. Therefore, a better understanding of the ability of WBE to precisely detect and track viral pathogens could provide insights into the system’s ability to serve as a valuable tool in the fight against infectious diseases like COVID-19.

Working with researchers at the Southern California Coastal Water Research Project, the UCI team monitored wastewater representing 16 million people in Southern California between August 2020 and January 2021.

“When the pandemic hit, and we heard about wastewater monitoring efforts, we immediately thought of the wastewater collection in our lab that we were using to hunt for phages – viruses that infect bacteria and could be used as alternatives to antibiotics,” said Katrine Whiteson, Ph.D., associate professor of molecular biology & biochemistry and co-corresponding author. “I am proud of the team of students mobilized by Jason Rothman in our lab to process and concentrate the wastewater to search for viruses.”

In order to assay RNA viruses in several Southern California sewersheds, a research team led by Whiteson and Rothman, Ph.D., a Hewitt Foundation Postdoctoral Fellow, collected and analyzed 94 wastewater influent samples across seven treatment plants over five months. The wastewater samples were subjected to metatranscriptomic sequencing and droplet digital PCR to characterize RNA viromes and SARS-CoV-2 viral load.

The researchers found that the viral load of specific waste treatment plants correlated with the weekly average of reported COVID-19 cases in that county. Because the team gathered samples longitudinally, they confirmed that the relative abundance of SARS-CoV-2 increased throughout the study in specific plants. Additionally, the researchers optimized their purification technique and detected SARS-CoV-2 single nucleotide variants in certain samples.

“Our study shows the usefulness of wastewater-based epidemiology and its importance in helping monitor COVID-19 across Southern California,” said Rothman, the study’s first author and co-corresponding author.

During the study, the team determined that the wastewater samples were rich in viral diversity, with most viruses being plant-infecting. Other human viruses of interest remained prevalent throughout the pandemic, including norovirus. The diversity and composition were dependent on the location of the waste treatment plant, which was also the case for human pathogenic viruses like SARS-CoV-2. The team suggests that future studies continue to refine their sample preparation methods and more comprehensive monitoring to help determine how pathogenic viruses change over time.    

“Our team was able to use cutting edge sequencing approaches to monitor not just the presence but also the diversity of wastewater representing 16 million people in Southern California,” said Whiteson.

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Additional Researchers who contributed to this work were: Theresa Loveless, Joseph Kapcia and Eric Adams from UCI; and Joshua Steele, Amity Zimmer-Faust, Kylie Langlois, David Wanless, Madison Griffith, Lucy Mao, Jeffrey Chokry and John Griffith from the Southern California Coastal Water Research Project. The authors would also like to thank Melanie Oakes from the UCI Genomics High Throughput Facility. The research was supported by grants from the University of California Office of the President and the Hewitt Foundation.

About the University of California, Irvine: Founded in 1965, UCI is the youngest member of the prestigious Association of American Universities and is ranked among the nation’s top 10 public universities by U.S. News & World Report. The campus has produced three Nobel laureates and is known for its academic achievement, premier research, innovation and anteater mascot. Led by Chancellor Howard Gillman, UCI has more than 36,000 students and offers 224 degree programs. It’s located in one of the world’s safest and most economically vibrant communities and is Orange County’s second-largest employer, contributing $7 billion annually to the local economy and $8 billion statewide. For more on UCI, visit www.uci.edu.

Media access: Radio programs/stations may, for a fee, use an on-campus ISDN line to interview UCI faculty and experts, subject to availability and university approval. For more UCI news, visit news.uci.edu. Additional resources for journalists may be found at communications.uci.edu/for-journalists. 

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JOURNAL

Applied and Environmental Microbiology

DOI

10.1128/AEM.01448-21 

ARTICLE TITLE

RNA viromics of Southern California wastewater and detection of SARS-CoV-2 single nucleotide variants.

ARTICLE PUBLICATION DATE

22-Sep-2021

Researchers want to develop new bio-plastics for use in optical technologies

Grant and Award Announcement

UNIVERSITÄT PADERBORN

Researchers want to develop new bio-plastics for use in optical technologies

Scientists from Paderborn University, Hamm-Lippstadt University of Applied Sciences and the Aachen-Maastricht Institute for Biobased Materials (AMIBM) are researching new environmentally-friendly plastic products based on lactic acid. The aim is to develop sustainable materials for optical applications such as headlights, lenses, reflectors and light guides. Up until now, these products have been made from petroleum-based plastics like polycarbonate and polymethyl methacrylate (PMMA), which pollute nature and the environment. The research project is funded by the German Federal Ministry of Food and Agriculture (BMEL) to the tune of approximately €885,000 and is part of its ‘Renewable Resources’ funding programme. The project, co-ordinated by the AMIBM, was initiated by Hamm-Lippstadt University of Applied Sciences, where predecessor project ‘Polylactide as a high-tech material for optical components of a luminaire – Renew-Opt’ was recently successfully completed.

The unrestricted production of petroleum-based plastic products is still standard practice, despite all efforts. Calls for alternatives based on renewable resources are not only growing louder in scientific and political circles, but are also being heard from society. “Currently, the focus is on applications with rather low material requirements and markets with high sales volumes. Some progress is being made in the field of optical materials. For example, in the form of ‘modified polycarbonates’, whereby isosorbide – a renewable resource – is used in the plastic as a second monomer. These materials are used in displays and optical films – though at the moment only very rarely,” says Professor Klaus Huber from the Department of Chemistry at Paderborn University, who is leading the project at the university. Professor Gunnar Seide from Maastricht University explains: “Unfortunately, sustainability is not yet a selling point for consumers. It is, of course, expected, but is expensive. This means that we need sustainable high-performance polymers with technical properties that are cost-effective. And this is what we are aiming to achieve with our PLANOM project.”

The scientists’ aim is to use a specific raw material from the bio-plastics family as an optical material in lights and headlights. Polylactide has emerged as a suitable candidate. “Polylactide, or polylactic acid, is obtained from renewable raw materials and is produced during the fermentation of carbohydrates in a process known as ‘lactic acid fermentation’. We know this from sauerkraut, for instance. With our approach, we address several problems with conventional polymer materials. The move towards short-term renewable resources helps establish a materials economy that is not dependent on petroleum and, at the same time, significantly cuts CO2 emissions, thereby contributing to the objectives of the Paris Agreement. A third aspect concerns looking at the entire material life cycle. This primarily involves avoiding microplastics, due to recycling concepts, and assessing biodegradability. As an exclusively bio-based polymer, polylactide is fully degradable under certain conditions. This reduces the amount of time it remains in nature. In addition to the necessary application-specific properties, these are major incentives for industry to switch to such alternative materials.” And polylactide not only offers advantages in terms of sustainability: “It also has very good optical properties for use in the visible area of the electromagnetic spectrum. Plus, the production capacities for polylactide are huge. This makes it relatively price-competitive compared to conventional polymers,” says Huber.

Research is initially being conducted into the use of polylactide in conjunction with LEDs, well-known as an efficient and environmentally-friendly light source. Huber explains: “In particular the extremely long service life and the radiation emitted at the short-wave end of the visible spectrum, i.e. the high blue component of LED light, place extreme demands on optical materials.” This means that extremely durable materials need to be used. The problem: Polylactide softens at around just 60 degrees Celsius. LED-based lights, however, can reach temperatures of up to 80 degrees when in use. A further challenge is its crystallisation behaviour. As of around 60 degrees, crystallites form that make the material cloudy. The scientists are working on either avoiding the formation of crystallites altogether or replacing this process with controlled crystallisation, whereby only crystallites with dimensions that do not interfere with the light are formed. “The project aims to make it possible to use polylactide in high-performance technical lighting applications for the very first time, specifically as a lens material in bike headlights. To this end, we’re working closely with the company Busch und Müller in Meinerzhagen. Other lighting companies, including HELLA in Lippstadt, are also interested in the progress we’re making and are seeing a growing need for the use of sustainable solutions in their products. In Lippstadt, we’re using specially developed equipment to investigate the resistance of the polylactides developed in the project to short-wave visible radiation,” says Professor Jörg Meyer from Hamm-Lippstadt University of Applied Sciences.

In Paderborn, the focus is on determining the molecular nature of the polylactides to be used, with a view to the subsequent use of the material. The researchers are in particular investigating the melting and crystallisation behaviour of the materials developed. Huber is investigating the extent to which additives or irradiation of the samples improve this behaviour with regard to the desired optical properties. “The work is being carried out using a small-angle light scattering system built especially for this purpose and enables us to investigate crystal growth and the melting process of crystals, i.e. precisely the processes that play a major role in determining the optical functionalities,” says Huber.

In addition to scientific and technical findings, the project is expected to provide significant economic stimuli. A sustainable optical bio-plastic with competitive properties will improve the competitiveness of light manufacturers and automotive suppliers. The project will also train early-career researchers and junior academics for positions in industry and research institutions. The team anticipates to have the first results at the end of 2022.

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