When bees nourish their microbiota

Peer-Reviewed Publication

UNIVERSITY OF LAUSANNE

Two teams from UNIL and EPFL have succeeded in demonstrating that the insect synthesizes nutrients for native gut microbes. A study published in « Nature Microbiology ».

Bacteria have adapted to all terrestrial environments. Some have evolved to survive in the gut of animals, where they play an important role for their host; they provide energy by degrading indigestible food, they train and regulate the immune system, they protect against invasion by pathogenic bacteria, and they synthesize neuroactive molecules that regulate the behavior and cognition of their host.

These are great advantages for the host, but what advantages do the bacteria derive? Certainly, the host provides a comfortable home, but does the host also provide nutrients to native bacteria that enable them to colonize?

It is a difficult question that is possible to answer with the aide of … bees. Professor Philipp Engel in UNIL's Department of Fundamental Microbiology (DMF) in Dorigny has set his sights on the western honey bee (Apis mellifera). They are a relatively simple system to study compared to humans and their gut microbiota. Best known for the delicious honey they produce, this insect is also an excellent experimental model for gut microbiota research: it has acquired a remarkably simple and stable microbiota, composed of only around twenty bacterial species. In the laboratory of the Engel group, bees are raised without gut bacteria, and then fed specific species that will colonize the gut. 

Full board for the bacteria

Bees love to gorge on nutrient rich pollen and honey, but they can also survive for long periods on a diet of only sugar water.  But what happens to the gut bacteria? A study published on January 15, 2024 in Nature Microbiology by the Lausanne scientists reveals new insights: Dr. Andrew Quinn and PhD candidate Yassine El Chazli began by looking for evidence that the bacteria share nutrients with one another when bees receive nothing more than sugar water. Remember that intestinal bacteria are known to consume dietary nutrients as well as waste products from other microorganisms.

However, their first results left them perplexed: One specific bacterium in the gut, Snodgrassella alvi, cannot metabolize sugar to grow, and yet it still colonized the bee gut when sugar was the only food in the diet and no other bacteria were present.  

By measuring metabolites in the gut, the scientists discovered that the bee synthesizes multiple acids (citric acid, malic acid, 3-hydroxy-3-methylglutaric acid, etc.) that are exported into the gut and were less abundant when S. alvi was present. These results led them to pose an unexpected hypothesis: Does the bee directly enable S. alvi to colonize its gut by furnishing the necessary nutrients? 

Picture proof

Proving this hypothesis was surprisingly difficult, but fortunately, the key expertise was just across the road in the laboratory of Professor Anders Meibom (affiliated with UNIL and EPFL). Professor Meibom and his team are experts in measuring the flux of metabolites in complex environments at nanometers scale resolution by using one of the few NanoSIMS (Nanoscale Secondary Ion Mass Spectrometry) instruments in Europe.

Together the two teams devised an experiment in which microbiota free bees received a special diet of glucose where the natural 12C atoms of carbon in the glucose were replaced with the naturally rare 13C “labelled” isotopes. The bees were then colonized with S. alvi. At the end of the experiment, the fixed guts embarked on a journey, first passing by the electron microscopy facility of UNIL, led by Senior Lecturer Christel Genoud. Then, they moved on to the laboratory of professor Meibom and his NanoSIMS. In the end, the scientists were able to construct a 2-dimensional “image” of the 13C atoms in the gut of the bee, which showed that the S. alvi cells were significantly enriched in 13C, which reflected the 13C enrichment of the acids present in the gut.

To the rescue of the bees

Thus, in a single image, the team was able to show conclusively that the bee synthesizes food for its intestinal bacteria. “This is a wonderful example of cutting-edge, truly interdisciplinary scientific collaboration, which has brought together several scientific units within UNIL and EPFL," comments Anders Meibom. When we work together in this way, there are not many academic environments in the world that have more to offer," adds the professor, who is a pioneer in the application of NanoSIMS technologies to the intransigent questions of biology.

"It's possible that many other gut microorganisms also feed on host-derived compounds," says co-lead author Dr. Andrew Quinn, imagining an extension of this approach to other bacteria. Refocusing on bees: "These results could also explain why bees have such a specialized and conserved gut microbiota." And these mechanisms could play a role in bees' vulnerability to climate change, pesticides, or new pathogens: "Their vulnerability could result from a disruption in this intricate metabolic synergy between the bee and its gut microbiota. We already know that exposure to the herbicide glyphosate makes bees more susceptible to pathogens and reduces the abundance of S. alvi in the gut. Now, armed with these new findings, we're looking for answers to these pressing questions."

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JOURNAL

Nature Microbiology

DOI

10.1038/s41564-023-01572-y 

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

'Host-derived organic acids enable gut colonization of the honey bee symbiont Snodgrassella alvi

ARTICLE PUBLICATION DATE

15-Jan-2024

 

Water molecule discovery contradicts textbook models

Peer-Reviewed Publication

UNIVERSITY OF CAMBRIDGE

 

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GRAPHIC REPRESENTATION OF THE LIQUID/AIR INTERFACE IN A SODIUM CHLORIDE SOLUTION, COURTESY YAIR LITMAN

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CREDIT: YAIR LIPMAN

Textbook models will need to be re-drawn after a team of researchers found that water molecules at the surface of salt water are organised differently than previously thought.

Many important reactions related to climate and environmental processes take place where water molecules interface with air. For example, the evaporation of ocean water plays an important role in atmospheric chemistry and climate science. Understanding these reactions is crucial to efforts to mitigate the human effect on our planet.

The distribution of ions at the interface of air and water can affect atmospheric processes. However, a precise understanding of the microscopic reactions at these important interfaces has so far been intensely debated.

In a paper published today in the journal Nature Chemistry, researchers from the University of Cambridge and the Max Planck Institute for Polymer Research in Germany show that ions and water molecules at the surface of most salt-water solutions, known as electrolyte solutions, are organised in a completely different way than traditionally understood. This could lead to better atmospheric chemistry models and other applications.

Technique

The researchers set out to study how water molecules are affected by the distribution of ions at the exact point where air and water meet. Traditionally, this has been done with a technique called vibrational sum-frequency generation (VSFG). With this laser radiation technique, it is possible to measure molecular vibrations directly at these key interfaces. However, although the strength of the signals can be measured, the technique does not measure whether the signals are positive or negative, which has made it difficult to interpret findings in the past. Additionally, using experimental data alone can give ambiguous results.

The team overcame these challenges by utilising a more sophisticated form of VSFG, called heterodyne-detected (HD)-VSFG, to study different electrolyte solutions. They then developed advanced computer models to simulate the interfaces in different scenarios.

The combined results showed that both positively charged ions, called cations, and negatively charged ions, called anions, are depleted from the water/air interface. The cations and anions of simple electrolytes orient water molecules in both up- and down-orientation. This is a reversal of textbook models, which teach that ions form an electrical double layer and orient water molecules in only one direction.

Co-first author Dr Yair Litman, from the Yusuf Hamied Department of Chemistry, said: “Our work demonstrates that the surface of simple electrolyte solutions has a different ion distribution than previously thought and that the ion-enriched subsurface determines how the interface is organised: at the very top there are a few layers of pure water, then an ion-rich layer, then finally the bulk salt solution."

Co-first author Dr Kuo-Yang Chiang of the Max Planck Institute said: “This paper shows that combining high-level HD-VSFG with simulations is an invaluable tool that will contribute to the molecular-level understanding of liquid interfaces.”

Professor Mischa Bonn, who heads the Molecular Spectroscopy department of the Max Planck Institute, added: “These types of interfaces occur everywhere on the planet, so studying them not only helps our fundamental understanding but can also lead to better devices and technologies. We are applying these same methods to study solid/liquid interfaces, which could have potential applications in batteries and energy storage.”

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JOURNAL

Nature Chemistry

DOI

10.1038/s41557-023-01416-6 

ARTICLE TITLE

Surface stratification determines the interfacial water structure of simple electrolyte solutions

ARTICLE PUBLICATION DATE

15-Jan-2024

 

U.S. air pollution rates on the decline but pockets of inequities remain

Decreases more substantial in high-income neighborhoods

Peer-Reviewed Publication

COLUMBIA UNIVERSITY'S MAILMAN SCHOOL OF PUBLIC HEALTH

Over the last decades, air pollution emissions have decreased substantially; however, the magnitude of the change varies by demographics, according to a new study by Columbia University Mailman School of Public Health. The results indicate there are racial/ethnic and socioeconomic disparities in air pollution emissions reductions, particularly in the industry and energy generation sectors. The findings are published in the journal Nature Communications.

The research provides a national investigation of air pollution emission changes in the 40 years following the enactment of the Clean Air Act (CAA). Until now, studies have primarily focused on evaluating air pollution disparities at a single time point, focusing on pollutant concentrations instead of emissions. A focus on emissions, however, has more direct implications for regulations and policies. In this study, the researchers used county-level data to evaluate racial/ethnic and socioeconomic disparities in air pollution emissions changes in the contiguous U.S. from 1970 to 2010.

“The analyses provide insight on the socio-demographic characteristics of counties that have experienced disproportionate decreases in air pollution emissions over the last forty years,” said Yanelli Nunez, PhD, the study’s first author, who is a scientist in the Department of Environmental Health Sciences at Columbia Mailman School of Public Health and affiliated with PSE Healthy Energy. Additionally, by analyzing air pollution emissions, the researchers identified specific pollution source sectors that are potentially important contributors to air pollution exposure disparities.

Nunez and colleagues leveraged air pollution emissions data from the Global Burden of Disease Major Air Pollution Sources inventory to analyze air pollutant emissions from six pollution source sectors: industry (sulfur dioxide), energy (sulfur dioxide and nitrogen oxides), agriculture (ammonia), on-road transportation (nitrogen oxides), commercial (nitrogen oxides), and residential (particles of organic carbon).

On average, national U.S.  air pollution emissions declined substantially from 1970 to 2010 from all source sectors the researchers considered except for ammonia emissions from agriculture and organic carbon particle emissions from the residential sector, which the researchers indicate is primarily from using solid biofuels for indoor heating. The most pronounced emission decreases were observed for sulfur dioxide from industrial and energy generation activities. Nitrogen oxide emissions from transportation, commercial activities, and energy generation decreased moderately.

Despite the overall downward trends for most pollutants, the researchers found that certain populations experienced relatively smaller reductions or even increases in air pollution emissions. For instance, an increase in a county's average Hispanic or Indian American population percentage resulted in a relative increase in sulfur dioxide, nitrogen oxides, and ammonia emissions from the industry, energy generation, and agriculture sectors, respectively. Additionally, an increase in the county median family income was linked with an increase in the magnitude of emissions reductions in every pollution source sector the researchers analyzed, except agriculture. 

“Air pollution emissions do not perfectly capture population air pollution exposure, and we also know that neighborhood-level air pollution inequities are common, which we were not able to analyze in this study given the data at hand,” noted Marianthi-Anna Kioumourtzoglou, ScD, associate professor of environmental health sciences at Columbia Mailman School, and senior author. “In this study, we provide information about potential racial/ethnic and socioeconomic inequalities in air pollution reductions nationwide from major air pollution sources, which can inform regulators and complement local-level analysis.”

“Policies specifically targeting reductions in overburdened populations could support more just reductions in air pollution and reduce disparities in air pollution exposure,” observed Dr. Nunez. “This is an important lesson gained from 53 years of Clean Air Act implementation, which is particularly relevant as we develop policies to transition to renewable energy sources, which will have a collateral impact on air quality and, as a result, on public health.”

Co-authors are Jaime Benavides, Jenni A. Shearston, Misbath Daouda, and Jeff Goldsmith, Columbia University Mailman School of Public Health; Joan Casey, Columbia Mailman School and the University of Washington; Elena Krieger, PSE Healthy Energy; Lucas R.F. Henneman, George Mason University; and Erin McDuffie, University of Washington.

The study was supported by National Institute of Environmental Health Sciences, (P30 ES009089, R01 ES030616, R01 ES028805 and T32 ES007322), The Thomas F. and Kate Miller Jeffress Memorial Trust, Bank of America; and Health Effects Institute (HEI, R-82811201).

Columbia University Mailman School of Public Health

Founded in 1922, the Columbia University Mailman School of Public Health pursues an agenda of research, education, and service to address the critical and complex public health issues affecting New Yorkers, the nation and the world. The Columbia Mailman School is the fourth largest recipient of NIH grants among schools of public health. Its nearly 300 multi-disciplinary faculty members work in more than 100 countries around the world, addressing such issues as preventing infectious and chronic diseases, environmental health, maternal and child health, health policy, climate change and health, and public health preparedness. It is a leader in public health education with more than 1,300 graduate students from 55 nations pursuing a variety of master’s and doctoral degree programs. The Columbia Mailman School is also home to numerous world-renowned research centers, including ICAP and the Center for Infection and Immunity. For more information, please visit www.mailman.columbia.edu.

 
 

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JOURNAL

Nature Communications

DOI

10.1038/s41467-023-43492-9 

 

New Scientific Reports publication reveals major difference in genomes of American and Chinese chestnut

Potential implications for American chestnut restoration and blight-resistance

Peer-Reviewed Publication

USDA FOREST SERVICE ‑ SOUTHERN RESEARCH STATION

 

IMAGE: 

CHROMOSOME SATELLITE FOR BOTH SPECIES (CHINESE CHESTNUT ON THE LEFT, AMERICAN CHESTNUT ON THE RIGHT). LIKE ALL CHROMOSOMES, THESE ARE MADE OF CHROMATIN – A MIX OF DNA MOLECULES AND PROTEINS. THERE ARE SEVERAL TYPES OF CHROMATIN. THE BRIGHT BLUE TIP IN THE CHINESE CHESTNUT INDICATES HETEROCHROMATIC DNA, AND THE LIGHTER PURPLE COLOR ON THE TIP MAY REPRESENT THE EUCHROMATIC DNA. THE ENTIRE REGION OF THE AMERICAN CHESTNUT SATELLITE APPEARS TO BE EUCHROMATIC. 

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CREDIT: USDA FOREST SERVICE IMAGE BY NURUL FARIDI.

The chromosomes of American and Chinese chestnut are not so similar after all, at least in one key region of the genome – the nucleolus organizing region (NOR). 

The finding, published in a forthcoming article in Scientific Reports, has major implications for anyone with the goal of conferring blight-resistance to American chestnuts through hybridization with the Chinese chestnut.  

“This is an unprecedented finding in the field of plant cytology,” says Nurul Faridi, a Forest Service geneticist and lead author of the study.   

Traditional backcross breeding, involving hybridization between two species, aims to combine an ideal mix of traits from two species without genetic engineering. Backcross breeding can only succeed when the chromosomes of both species are compatible. Because Chinese-American chestnut hybrids are viable, people have assumed that the two species are highly compatible. But the new study reveals significant differences in the NOR of the two species.   

The NOR is part of every plant and animal cell. It carries the genetic instructions for making ribosomes – the molecular machines that make the proteins essential for life. 

The NOR is located near the end of the short arm of a particular chromosome. It is present on both species, but in Chinese chestnut it is packed with a type of DNA known as heterochromatin and constitutes about 25% of the chromosome. The structure and composition of this DNA surprised the researchers – it is highly condensed, lacking gene content, and transcriptionally inactive. In contrast, the American chestnut satellite is very small and appeared to be euchromatic. Euchromatic regions of DNA are transcriptionally active. 

Faridi first noticed a small pair of Chinese chestnut chromosomes exhibiting very bright fluorescence with a specialized microscope, a UV filter, and a dye that binds to the DNA.  

Faridi used a technique called fluorescent in situ hybridization (FISH) to further analyze the discovery.  

“Our high-quality FISH images provide unequivocal evidence of this unique DNA arrangement,” says Faridi. “These images are not just pictures; they are a testament to the dynamic nature of genetic material.”   

Faridi has been working with FISH since 1991 and has extensive experience preparing plant chromosomes for analyses. Well-separated chromosomes from enzymatically digested root tips that are mostly free of cell walls, nuclear membranes, and cytoplasmic debris are best for FISH.  

Most FISH imagery is obtained from animal cells, as plant cells, and especially trees, are more challenging to work with. Faridi has found that chestnuts are far more difficult to work with than pine and poplar.  

The researchers will use a technique called oligonucleotide FISH for further investigation. Oligo-FISH uses short specific DNA probes acquired from DNA sequencing. Since the entire genomes of American and Chinese chestnut have been sequenced, oligo-FISH will allow the researchers to make detailed genetic studies that will discern subtle genomic differences. The technique is especially useful for studying hybrids since it can indicate which parent a gene is from.  

The progress in developing American chestnut hybrids with height of the American chestnut and the blight-resistance of the Chinese chestnut has been significant. However, the most advanced hybrids do not currently have enough blight resistance for restoration, as previous Forest Service research has shown.  

In addition to Faridi and C. Dana Nelson of the USDA Forest Service Southern Research Station, the genetics team included researchers from Texas A&M University, Pennsylvania State University, University of Kentucky, and The American Chestnut Foundation.  

The paper will be published in Scientific Reports on January 15, 2024. DOI: 10.1038/s41598-023-45879-6

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JOURNAL

Scientific Reports

DOI

10.1038/s41598-023-45879-6 

SUBJECT OF RESEARCH

Cells

ARTICLE TITLE

Cyto‑molecular characterization of rDNA and chromatin composition in the NOR‑associated satellite in Chestnut (Castanea spp.)

ARTICLE PUBLICATION DATE

15-Jan-2024

 

Research sheds new light on Moon rock formation solving major puzzle in lunar geology

Peer-Reviewed Publication

UNIVERSITY OF BRISTOL

 

IMAGE: 

IMAGE SHOWS ASTRONAUT-GEOLOGIST STANDING NEXT TO A HUGE LUNAR BOULDER DURING NASA’S APOLLO 17 MISSION IN 1972. THE SCIENTISTS IN THIS RESEARCH USED ROCK SAMPLES FROM THIS APOLLO MISSION.

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CREDIT: NASA/EUGENE CERNAN

New research has cracked a vital process in the creation of a unique rock type from the Moon. The discovery explains its signature composition and very presence on the lunar surface at all, unravelling a mystery which has long eluded scientists.

The study, published today in Nature Geoscience, reveals a key step in the genesis of these distinctive magmas.  A combination of high temperature laboratory experiments using molten rocks, together with sophisticated isotopic analyses of lunar samples, identify a critical reaction that controls their composition.

This reaction took place in the deep lunar interior some three and a half billion years ago, involving exchange of the element iron (Fe) in the magma with the element magnesium (Mg) in the surrounding rocks, modifying the chemical and physical properties of the melt.  

Co-lead author Tim Elliott, Professor of Earth Sciences at the University of Bristol, said: “The origin of volcanic lunar rocks is a fascinating tale involving an ‘avalanche’ of an unstable, planetary-scale crystal pile created by the cooling of a primordial magma ocean. 

“Central to constraining this epic history is the presence of a magma type unique to the Moon, but explaining how such magmas could even have got to the surface, to be sampled by Space missions, has been a troublesome problem. It is great to have resolved this dilemma.”

Surprisingly high concentrations of the element titanium (Ti) in parts of the lunar surface have been known since the NASA Apollo missions, back in the 1960s and 1970s, which successfully returned solidified, ancient lava samples from the Moon’s crust. More recent mapping by orbiting satellite shows these magmas, known as ‘high-Ti basalts’, to be widespread on the Moon.

“Until now models have been unable to recreate magma compositions that match essential chemical and physical characteristics of the high-Ti basalts. It has proven particularly hard to explain their low density, which allowed them to be erupted some three and a half billion years ago,” added co-lead author Dr Martijn Klaver, Research Fellow at the University of Münster Institute of Mineralogy.

The international team of scientists, led by the Universities of Bristol in the UK and Münster in Germany managed to mimic the high-Ti basalts in the process in the lab using high-temperature experiments.  Measurements of the high-Ti basalts also revealed a distinctive isotopic composition that provides a fingerprint of the reactions reproduced by the experiments.

Both results clearly demonstrate how the melt-solid reaction is integral in understanding the formation of these unique magmas. 

Image shows Moon rock, known as high-Ti basalt, sample from Apollo 17 mission like those analysed in this study.

Image shows a map of the Titanium abundances of the Moon’s surface, obtained from NASA’s Clementine spacecraft. The red parts indicate extremely high concentrations compared to terrestrial rocks.

CREDIT

Lunar and Planetary Institute

An electron-microscope image of an experiment from this study. Melt (brown colour) reacts with surrounding crystals (green colours), resulting in a less Fe-rich melt.

CREDIT

University of Bristol/University of Münster

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JOURNAL

Nature Geoscience

ARTICLE TITLE

‘Titanium-rich basaltic melts on the Moon modulated by reactive flow processes’

ARTICLE PUBLICATION DATE

15-Jan-2024

 

Going beyond plastic: Chung-Ang University team explores tara gum as a green polymer

The gum, and its modified forms, can find use as a sustainable and biodegradable polymer in food and drug industries

Peer-Reviewed Publication

CHUNG ANG UNIVERSITY

 

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RESEARCHERS REVIEW THE APPLICATION OF TARA GUM AND ITS MODIFIED FORMS AS A SUSTAINABLE AND BIODEGRADABLE POLYMER IN FOOD AND DRUG INDUSTRIES.

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CREDIT: SCAMPERDALE FROM FLICKR (HTTPS://WWW.FLICKR.COM/PHOTOS/36517976@N06/6363740405) AND SANGKIL LEE FROM CAU

Synthetic, non-biodegradable plastics are major sources of environmental pollution and have prompted a rising interest in sustainable, biodegradable alternatives derived from natural polymers. “Tara gum,” derived from the seeds of the tara tree (Caesalpinia spinosa), stands out as a promising solution. This natural, water-soluble substance contains polysaccharides (complex carbohydrates), including the widely used “galactomannan,” which is employed in coatings, edible films, and as a stabilizer and thickener. The biocompatibility, biodegradability, and safety of tara gum also make it valuable in industries like food and drug delivery. Moreover, the adaptable nature of the groups within tara gum polysaccharides renders it valuable for tailoring physicochemical and mechanical properties for specific applications.

In a recent study, made available online on 29 September 2023 and to be published in Volume 323 of Carbohydrate Polymers on 1 January 2024, a team of researchers, led by Professor Sangkil Lee from Chung-Ang University in the Republic of Korea, has now conducted a thorough and critical examination of modification methods (“grafting”) applied to tara gum. The study explores the applications of these modifications in the food and drug industry, including the development of pH-sensitive food packaging and drug delivery systems.

Prof. Lee explains: “Our team has a keen interest in natural polysaccharides and their role in drug delivery, and we have been working on tara gum and other natural polysaccharides to extend their applications. Various researchers have explored the wide range of applications for its various modified forms. However, this is the first review article on recent advancements in tara gum and its modified materials, and their potential role in food and drug delivery.”

The team presents a systematic and detailed overview of various advancements in tara gum research. They describe methods for the extraction, isolation, and characterization of tara gum polysaccharides. Additionally, the toxicology and rheological (deformation) behavior of tara gum, along with its behavior in the presence of other polysaccharides, are thoroughly examined.

The review paper also delves into the applications of tara gum and its modified derivatives in the food industry. These include the use in biopolymer packaging, monitoring seafood and milk spoilage, acting as a gelation agent, providing short-term protection of food from oxidation, and safeguarding fatty foods. The applications of tara gum and its modified materials have been detailed for the pharmaceutical industry as well, including the controlled-release of vitamin D-3, antibacterial hydrogel development, iron delivery in both infants and adults, controlled-release of drugs, and restoration of the physiological barrier of the gut.

“The physicochemical property of tara gum and its products can be enhanced using various kinds of monomers, crosslinkers, or other polysaccharides. Furthermore, the improvement of antibacterial properties might be achieved through the incorporation of chitosan or other natural polymers, as well as inorganic materials such as copper and zinc nanoparticles,” speculates Prof. Lee.

The study could thus inspire the scientific community to research further on tara gum for the development of various food-related applications as well as effective and safe drug formulations to reduce the global burden of health risks and costs.

 

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Reference

DOI: https://doi.org/10.1016/j.carbpol.2023.121440

 

Authors: Vinit Raj1, Kyung-Soo Chun2,3, and Sangkil Lee1

 

Affiliations:

1College of Pharmacy, Chung-Ang University

2College of Pharmacy, Keimyung University

3Center for Forensic Pharmaceutical Science, Keimyung University

 

About Chung-Ang University
Chung-Ang University is a private comprehensive research university located in Seoul, South Korea. It was started as a kindergarten in 1916 and attained university status in 1953. It is fully accredited by the Ministry of Education of Korea. Chung-Ang University conducts research activities under the slogan of “Justice and Truth.” Its new vision for completing 100 years is “The Global Creative Leader.” Chung-Ang University offers undergraduate, postgraduate, and doctoral programs, which encompass a law school, management program, and medical school; it has 16 undergraduate and graduate schools each. Chung-Ang University’s culture and arts programs are considered the best in Korea.

Website: https://neweng.cau.ac.kr/index.do

 

About Professor Sangkil Lee
Sangkil Lee is a Full Professor of the College of Pharmacy at Chung-Ang University, Seoul, Republic of Korea. His group has been developing various kinds of drug formulations at the preclinical level through nanotechnology/drug conjugation and polymeric hydrogels for regenerative medicine. Prof. Lee's group is also developing nanocomplex formulations as drugs using in-silico drug design and formulating development approaches for Alzheimer’s disease and other conditions.

Read more: https://scholarworks.bwise.kr/cau/researcher-profile?ep=1459

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JOURNAL

Carbohydrate Polymers

DOI

10.1016/j.carbpol.2023.121440 

METHOD OF RESEARCH

Systematic review

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

State-of-the-art advancement in tara gum polysaccharide (Caesalpinia spinosa) modifications and their potential applications for drug delivery and the food industry

 

Chasing the light: Sandia study finds new clues about warming in the Arctic

Study focuses on reduction in sunlight reflectivity

Business Announcement

DOE/SANDIA NATIONAL LABORATORIES

 

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A SANDIA NATIONAL LABORATORIES STUDY USED PREVIOUSLY UNPUBLISHED DATA FROM GPS MONITORS TO LEARN MORE ABOUT WHAT’S DECREASING THE SUN’S REFLECTIVITY IN THE ARCTIC.

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CREDIT: SANDIA NATIONAL LABORATORIES

ALBUQUERQUE, N.M. — The Arctic, Earth’s icy crown, is experiencing a climate crisis like no other. It’s heating up at a furious pace — four times faster than the rest of our planet. Researchers at Sandia National Laboratories are pulling back the curtain on the reduction of sunlight reflectivity, or albedo, which is supercharging the Arctic’s warming.

The scientists are not armed with parkas and shovels. Instead, they have tapped into data from GPS satellite radiometers, capturing the sunlight bouncing off the Arctic. This data dive could be the key to cracking the Arctic amplification code.

“The uneven warming in the Arctic is both a scientific curiosity and a pressing concern, leading us to question why this landscape has been changing so dramatically,” said Erika Roesler, an atmospheric and climate scientist at Sandia.

Previous studies have suggested that sea-ice albedo feedbacks are likely driving Arctic amplification. These albedo feedbacks can be broken down into two main areas. First, there’s an overall reduction in sea ice, leading to more exposure of the dark ocean. This absorbs more sunlight than snow-covered ice and raises temperatures. The second factor is the reflectivity of the remaining sea ice, or local albedo, which includes ponding water on ice due to melting.

Sandia researchers aimed to gain a better understanding of the reduction in reflectivity in the Arctic. Senior scientist Phil Dreike collaborated with the U.S. Space Force to obtain permission for Sandia to analyze previously unpublished data from the radiometers on GPS satellites.

“New observational climate datasets are unique," Roesler said. "To qualify as a climate dataset, observations must span a multitude of years. Small-scale science projects are typically not that long in duration, making this dataset particularly valuable."

Amy Kaczmarowski, an engineer at Sandia, conducted an analysis of the data spanning from 2014 to 2019.

“There have been numerous local measurements and theoretical discussions regarding the effects of water puddling on ice albedo," Kaczmarowski said. "This study represents one of the first comprehensive examinations of year-to-year effects in the Arctic region. Sandia’s data analysis revealed a 20% to 35% decrease in total reflectivity over the Arctic summer. According to microwave sea-ice extent measurements collected during the same period, one-third of this loss of reflectivity is attributed to fully melted ice.”

The other two-thirds of the loss in reflectivity is likely caused by the weathering of the remaining sea ice.

“The key discovery here is just how much the weathered ice is reducing reflectivity,” Kaczmarowski added. Weathered ice refers to the remaining sea ice, which can be thinner and may contain melt ponds.

The GPS satellites are expected to continue providing data through 2040. The Sandia team hopes other researchers will consider their findings, recently published in the journal Nature Scientific Reports, and incorporate them into their models for Arctic amplification. They plan to continue mining the GPS data and are enthusiastic about collaborating with other climate researchers for further analysis.

“We will continue to use this data to investigate various regions of the Earth for climate applications,” Kaczmarowski said.

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Sandia National Laboratories is a multimission laboratory operated by National Technology and Engineering Solutions of Sandia LLC, a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy’s National Nuclear Security Administration. Sandia Labs has major research and development responsibilities in nuclear deterrence, global security, defense, energy technologies and economic competitiveness, with main facilities in Albuquerque, New Mexico, and Livermore, California

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METHOD OF RESEARCH

Data/statistical analysis

Arctic albedo animation [VIDEO] | 

Researchers at Sandia National Laboratories are taking a closer look at what's causing a decrease in sunlight reflectivity, or albedo, in the Arctic. Watch an animation showing the albedo process.

CREDIT

Sandia National Laboratories