Monday, August 23, 2021

 

Interstellar comets like Borisov may not be all that rare

Peer-Reviewed Publication

HARVARD-SMITHSONIAN CENTER FOR ASTROPHYSICS

Interstellar Comets Like Borisov May Not be All That Rare 

IMAGE: DETECTED IN 2019, THE BORISOV COMET WAS THE FIRST INTERSTELLAR COMET KNOWN TO HAVE PASSED THROUGH OUR SOLAR SYSTEM. view more 

CREDIT: CREDIT: NASA, ESA AND D. JEWITT (UCLA)

Cambridge, MASS. – In 2019, astronomers spotted something incredible in our backyard: a rogue comet from another star system. Named Borisov, the icy snowball traveled 110,000 miles per hour and marked the first and only interstellar comet ever detected by humans. 

But what if these interstellar visitors—comets, meteors, asteroids and other debris from beyond our solar system—are more common than we think?

In a new study published Monday in the Monthly Notices of the Royal Astronomical Society, astronomers Amir Siraj and Avi Loeb at the Center for Astrophysics | Harvard & Smithsonian (CfA) present new calculations showing that in the Oort Cloud—a shell of debris in the farthest reaches of our solar system—interstellar objects outnumber objects belonging to our solar system.

“Before the detection of the first interstellar comet, we had no idea how many interstellar objects there were in our solar system, but theory on the formation of planetary systems suggests that there should be fewer visitors than permanent residents,” says Siraj, a concurrent undergraduate and graduate student in Harvard’s Department of Astronomy and lead author of the study. “Now we’re finding that there could be substantially more visitors.”

The calculations, made using conclusions drawn from Borisov, include significant uncertainties, Siraj points out. But even after taking these into consideration, interstellar visitors prevail over objects that are native to the solar system.

“Let’s say I watch a mile-long stretch of railroad for a day and observe one car cross it. I can say that, on that day, the observed rate of cars crossing the section of railroad was one per day per mile,” Siraj explains. “But if I have a reason to believe that the observation was not a one-off event—say, by noticing a pair of crossing gates built for cars—then I can take it a step further and begin to make statistical conclusions about the overall rate of cars crossing that stretch of railroad.”

But if there are so many interstellar visitors, why have we only ever seen one? 

We just don’t have the technology to see them yet, Siraj says. 

Consider, he says, that the Oort Cloud spans a region some 200 billion to 100 trillion miles away from our Sun—and unlike stars, objects in the Oort Cloud don’t produce their own light. Those two factors make debris in the outer solar system incredibly hard to see. 

Senior astrophysicist Matthew Holman, who was not involved in the research, says the study results are exciting because they have implications for objects even closer than the Oort Cloud. 

"These results suggest that the abundances of interstellar and Oort cloud objects are comparable closer to the Sun than Saturn. This can be tested with current and future solar system surveys," says Holman, who is the former director of the CfA’s Minor Planet Center, which tracks comets, asteroids and other debris in the solar system. 

“When looking at the asteroid data in that region, the question is: are there asteroids that really are interstellar that we just didn’t recognize before?” he asks.  

Holman explains that there are some asteroids that get detected but aren’t observed or followed up on year after year. “We think they are asteroids, then we lose them without doing a detailed look.”

Loeb, study co-author and Harvard astronomy professor, adds that “interstellar objects in the planetary region of the solar system would be rare, but our results clearly show they are more common than solar system material in the dark reaches of the Oort cloud."

Observations with next-generation technology may help confirm the team’s results.

The launch of the Vera C. Rubin Observatory, slated for 2022, will “blow previous searches for interstellar objects out of the water,” Siraj says, and hopefully help detect many more visitors like Borisov.   

The Transneptunian Automated Occultation Survey (TAOS II), which is specifically designed to detect comets in the far reaches of our solar system, may also be able to detect one of these passersby. TAOS II may come online as early as this year.

The abundance of interstellar objects in the Oort Cloud suggests that much more debris is left over from the formation of planetary systems than previously thought, Siraj says. 

"Our findings show that interstellar objects can place interesting constraints on planetary system formation processes, since their implied abundance requires a significant mass of material to be ejected in the form of planetesimals,” Siraj says. “Together with observational studies of protoplanetary disks and computational approaches to planet formation, the study of interstellar objects could help us unlock the secrets of how our planetary system — and others — formed." 

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About the Center for Astrophysics | Harvard & Smithsonian

The Center for Astrophysics | Harvard & Smithsonian is a collaboration between Harvard and the Smithsonian designed to ask—and ultimately answer—humanity’s greatest unresolved questions about the nature of the universe. The Center for Astrophysics is headquartered in Cambridge, MA, with research facilities across the U.S. and around the world.

This technology could bring the fastest version of 5G to your home and workplace


UC San Diego engineers developed a system that enables millimeter wave signals to overcome blockages while providing high throughput


Reports and Proceedings

UNIVERSITY OF CALIFORNIA - SAN DIEGO

Making high band 5G reliable experimental setup 

IMAGE: EXPERIMENTAL SETUP OF THE MULTI-BEAM MILLIMETER WAVE SYSTEM. view more 

CREDIT: ISH JAIN

Consumers of today’s 5G cellphones may have experienced one of the following tradeoffs: impressive download speeds with extremely limited and spotty coverage, or widespread and reliable coverage with speeds that aren’t much faster than today’s 4G networks.

A new technology developed by electrical engineers at the University of California San Diego combines the best of both worlds and could enable 5G connectivity that is ultra-fast and reliable at the same time.

The team will present their work at the ACM SIGCOMM 2021 conference which will take place online Aug. 23 to 27.

The technology presents a solution to overcome a roadblock to making high band 5G practical for the everyday user: the speedy wireless signals, known as millimeter waves, cannot travel far and are easily blocked by walls, people, trees and other obstacles.

Today’s high band 5G systems communicate data by sending one laser-like millimeter wave beam between a base station and a receiver—for example, a user’s phone. The problem is if something or someone gets in the way of that beam’s path, then the connection gets blocked completely.

“Relying on a single beam creates a single point of failure,” said Dinesh Bharadia, a professor of electrical and computer engineering at the UC San Diego Jacobs School of Engineering, who is the senior author on the ACM SIGCOMM paper.

Two beams are better than one

Bharadia and his team, who are part of the UC San Diego Center for Wireless Communications, came up with a clever solution: split the one laser-like millimeter wave beam into multiple laser-like beams, and have each beam take a different path from the base station to the receiver. The idea is to improve the chances that at least one beam reaches the receiver when an obstacle is in the way.

The researchers created a system capable of doing this and tested it inside an office and outside a building on campus. The system provided a high throughput connection (up to 800 Mbps) with 100% reliability, which means that the signal didn’t drop or lose strength as the user moved around obstacles like desks, walls and outdoor sculptures. In outdoor tests, the system provided connectivity up to 80 meters (262 feet) away.

To create their system, the researchers developed a set of new algorithms. One algorithm first instructs the base station to split the beam into multiple paths. Some of these paths take a direct shot from the base station and the receiver; and some paths take an indirect route, where the beams bounce off what are called reflectors—surfaces in the environment that reflect millimeter waves like glass, metal, concrete or drywall—to get to the receiver. The algorithm then learns which are the best paths in the given environment. It then optimizes the angle, phase and power of each beam so that when they arrive at the receiver, they combine constructively to create a strong, high quality and high throughput signal.

CAPTION

Hardware of the multi-beam millimeter wave system.

CREDIT

Ish Jain

With this approach, more beams result in a stronger signal.

“You would think that splitting the beam would reduce the throughput or quality of the signal,” Bharadia said. “But with the way that we’ve designed our algorithms, it turns out mathematically that our multi-beam system gives you a higher throughput while transmitting the same amount of power overall as a single-beam system.”

The other algorithm maintains the connection when a user moves around and when another user steps in the way. When these happen, the beams get misaligned. The algorithm overcomes this issue by continuously tracking the user’s movement and realigning all the beam parameters.

The researchers implemented their algorithms on cutting-edge hardware that they developed in the lab. “You don’t need any new hardware to do this,” said Ish Jain, an electrical and computer engineering Ph.D. student in Bharadia’s lab and the first author of the paper. “Our algorithms are all compliant with current 5G protocols.”

The hardware consists of a small base station and receiver. The base station is equipped with a phased array that was developed in the lab of UC San Diego electrical and computer engineering professor Gabriel Rebeiz, who is an expert in phased arrays for 5G and 6G communications and is also a member of the university’s Center for Wireless Communications.

The team is now working on scaling their system to accommodate multiple users.

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More information can be found on the project’s website: https://wcsng.ucsd.edu/mmreliable/

Paper: “Two beams are better than one: Towards Reliable and High Throughput mmWave Links.” Co-authors include Raghav Subbaraman, UC San Diego.

This work is supported by the National Science Foundation (grant 1925767).

Wildfire smoke exposure during pregnancy increases preterm birth risk


Wildfire smoke and early births


Peer-Reviewed Publication

STANFORD UNIVERSITY

Average number of smoke days per year 

IMAGE: AVERAGE NUMBER OF SMOKE DAYS PER YEAR. view more 

CREDIT: HEFT-NEAL ET AL. 2021, ENVIRONMENTAL RESEARCH

Exposure to wildfire smoke during pregnancy increases the risk that a baby will be born too early, a new Stanford University study suggests.

The study, published Aug. 14 in Environmental Research, finds there may have been as many as 7,000 extra preterm births in California attributable to wildfire smoke exposure between 2007 and 2012. These births occurred before 37 weeks of pregnancy when incomplete development heightens risk of various neurodevelopmental, gastrointestinal and respiratory complications, and even death.

Wildfire smoke contains high levels of the smallest and deadliest type of particle pollution, known as PM 2.5. These specks of toxic soot, or particulate matter, are so fine they can embed deep in the lungs and pass into the bloodstream, just like the oxygen molecules we need to survive.

The research comes as massive wildfires are again blazing through parched landscapes in the western U.S. – just a year after a historic wildfire season torched more than 4 million acres of California and produced some of the worst daily air pollution ever recorded in the state. During the 2020 fire season, more than half of the state’s population experienced a month of wildfire smoke levels in the range of unhealthy to hazardous.

This year could be worse, said Stanford environmental economist Marshall Burke, a co-author of the new study. And yet much remains unknown about the health impacts of these noxious plumes, which contribute a growing portion of fine particle pollution nationwide and have a different chemical makeup from other ambient sources of PM 2.5, such as agriculture, tailpipe emissions and industry.

One possible explanation for the link between wildfire smoke exposure and preterm birth, the authors say, is that the pollution may trigger an inflammatory response, which then sets delivery in motion. The increase in risk is relatively small in the context of all the factors that contribute to the birth of a healthy, full-term baby. “However, against a backdrop where we know so little about why some women deliver too soon, prematurely, and why others do not, finding clues like the one here helps us start piecing the bigger puzzle together,” said co-author Gary Shaw, DrPH, a professor of pediatrics and co-primary investigator of Stanford’s March of Dimes Prematurity Research Center.

Extreme wildfires

The new results show wildfire smoke may have contributed to more than 6 percent of preterm births in California in the worst smoke year of the study period, 2008, when a severe lightning storm, powerful winds, high temperatures and a parched landscape combined for a deadly and destructive fire season – one that has now been dwarfed by the record-setting infernos of 2020 and ongoing blazes like the Dixie fire in Northern California.

“In the future, we expect to see more frequent and intense exposure to wildfire smoke throughout the West due to a confluence of factors, including climate change, a century of fire suppression and construction of more homes along the fire-prone fringes of forests, scrublands and grasslands. As a result, the health burden from smoke exposure – including preterm births – is likely to increase,” said lead author Sam Heft-Neal, a research scholar at Stanford’s Center on Food Security and the Environment.

The research provides new evidence for the value of investing in prescribed burns, mechanical thinning, or other efforts to reduce the risk of extreme wildfires. Given that premature births cost the U.S. healthcare system an estimated $25 billion per year, even modest reductions in preterm birth risk could yield “enormous societal benefits,” said Burke, an associate professor of Earth system science at Stanford’s School of Earth, Energy & Environmental Sciences (Stanford Earth). “Our research highlights that reducing wildfire risk and the air pollution that accompanies it is one way of achieving these societal benefits.”

‘No safe level of exposure’

The researchers analyzed satellite data of smoke plumes from the National Oceanic and Atmospheric Administration (NOAA) to identify smoke days for each of 2,610 zip codes. They paired these data with estimates of ground-level PM 2.5 pollution, which were developed using a machine learning algorithm that incorporates data from air quality sensors, satellite observations and computer models of how chemicals move through Earth’s atmosphere. They pulled additional data from California birth records, excluding twins, triplets and higher multiples, which commonly arrive early.

After accounting for other factors known to influence preterm birth risk, such as temperature, baseline pollution exposure and the mother’s age, income, race or ethnic background, they looked at how patterns of preterm birth within each zip code changed when the number and intensity of smoke days rose above normal for that location.

They found every additional day of smoke exposure during pregnancy raised the risk of preterm birth, regardless of race, ethnicity or income. And a full week of exposure translated to a 3.4 percent greater risk relative to a mother exposed to no wildfire smoke. Exposure to intense smoke during the second trimester – between 14 and 26 weeks of pregnancy – had the strongest impact, especially when smoke contributed more than 5 additional micrograms per cubic meter to daily PM 2.5 concentrations. “If one can avoid smoke exposure by staying indoors or wearing an appropriate mask while outdoors, that would be good health practice for all,” Shaw said.

The findings build on an established link between particle pollution and adverse birth outcomes, including preterm birth, low birth weight and infant deaths. But the study is among the first to isolate the effect of wildfire smoke on early births and to tease out the importance of exposure timing.

“Our work, together with a number of other recent papers, clearly shows that there’s no safe level of exposure to particulate matter. Any exposure above zero can worsen health impacts,” said Burke, who is also deputy director of the Center on Food Security and the Environment and a senior fellow at Stanford’s Freeman Spogli Institute for International Studies. “While as a society it will be extremely difficult to fully eliminate all pollutants from the air, our research suggests that further reductions in key pollutants below current ‘acceptable’ levels could be massively beneficial for public health.”

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This work was supported by the Robert Wood Johnson Foundation and the March of Dimes Prematurity Research Center at Stanford University School of Medicine.

Shaw is NICU Nurses Professor and Professor (Research) by Courtesy, of Epidemiology and Population Health and of Obstetrics and Gynecology (Maternal Fetal Medicine). Burke is a Senior Fellow at Stanford Woods Institute for the Environment and at the Stanford Institute for Economic Policy Research.

Gene editing could render mosquitos infertile, reducing disease spread


Peer-Reviewed Publication

U.S. ARMY RESEARCH LABORATORY

Gene editing could render mosquitos infertile, reducing disease spread 

IMAGE: NEW U.S. ARMY-FUNDED RESEARCH USES GENE EDITING TO RENDER CERTAIN MALE MOSQUITOES INFERTILE AND SLOW THE SPREAD OF DISEASES LIKE ZIKA AND YELLOW FEVER. view more 

CREDIT: UNIVERSITY OF CALIFORNIA SANTA BARBARA

RESEARCH TRIANGLE PARK, N.C. -- Mosquitos spread viruses that cause potentially deadly diseases such as Zika, dengue fever and yellow fever. New U.S. Army-funded research uses gene editing to render certain male mosquitoes infertile and slow the spread of these diseases.

Researchers at the Army’s Institute for Collaborative Biotechnologies and the University of California Santa Barbara used a gene editing tool known as CRISPR-Cas9 to target a specific gene tied to fertility in male mosquitoes. CRISPR-Cas9 is a genome editing tool that is creating a buzz in the science world, according to yourgenome.org. It is “faster, cheaper and more accurate than previous techniques of editing DNA and has a wide range of potential applications.”

Researchers experimented with the Aedes aegypti mosquitoes, which are found in tropical, subtropical and temperate regions throughout the world. The study, published in the Proceedings of the National Academy of Sciences, discerned how a mutation can suppress the fertility of female mosquitoes.

“This is yet one more important and exciting example of how synthetic biology tools are demonstrating unparalleled utility,” said Dr. James Burgess, ICB program manager for the U.S. Army Combat Capabilities Development Command, now known as DEVCOM, Army Research Laboratory. “In this case, it’s a precision increase from chainsaw to a scalpel leading to the correct biochemical outcome that could substantially reduce the population of a very infectious mosquito.”

To manage populations, scientists use a vector-control practice called the sterile insect technique in which they raise a lot of sterile male insects and they then release these males in numbers that overwhelm their wild counterparts. Females that mate with sterile males before finding a fertile one are themselves rendered infertile, thereby decreasing the size of the next generation.

Repeating this technique several times has the potential to crash the population because each generation is smaller than the last; releasing a similar number of sterile males has a stronger effect over time.

 

The sterile insect technique is effective in managing a number of agricultural pests, including the Mediterranean fruit fly, a crop pest in California. It has also been attempted with Aedes aegypti mosquitoes, but with limited success.

In the past, scientists used chemicals or radiation to sterilize male Aedes aegypti, but the chemicals or radiation impacted the mosquitos’ health to such an extent that they were less successful in mating with females, which undercuts the effectiveness of the sterile insect technique.

The research team wanted to identify a more targeted approach with less collateral damage, mutating a gene in mosquitoes that specifically caused male sterility without otherwise impacting the insects’ health.

“When CRISPR/Cas9 came out several years ago it just offered new opportunities to do things that you couldn’t do before,” said Dr. Craig Montell, distinguished professor at UC Santa Barbara. “So, the time seemed right to for us to start working on Aedes aegypti.”

Using gene editing in male Aedes aegypti, researchers found that the mutant male mosquitos produced no sperm, and unlike in previous efforts, the sterile studs were otherwise completely healthy; however, the team wasn’t sure whether sperm, albeit defective sperm from the sterile males, was needed to render female mosquitoes infertile, or whether the transfer of seminal fluid was all it took.

In one experiment, researchers introduced 15 mutant males into a group of 15 females for 24 hours. Then they swapped the males for 15 wild-type males, and left them there.

“Essentially, all of the females remained sterile,” Montell said. “This confirmed that males could suppress female fertility without producing sperm.”

Next the researchers set out to determine how timing played into the effect. They exposed the females to mutant males for different lengths of time. The scientists noticed little difference after 30 minutes, but female fertility quickly dropped after that. Montell noted that females copulated twice on average, even during the first 10 minutes. This indicated that females have to mate with many sterile males before being rendered infertile themselves.

Combining the females with the males for four hours cut female fertility to 20% of normal levels. After eight hours the numbers began leveling out around 10%.

According to Montell, Aedes aegypti populations could easily bounce back from an 80% drop in fertility. The success of sterile insect technique comes from subsequent, successive releases of sterile males, where each release will be more effective than the last as sterile males account for an ever-growing proportion of the population.

The team plans to continue investigating mosquito mating behaviors and fertility. They are devising a way to maintain stocks of males so they are only sterile in the wild and not in the lab. In addition, they are characterizing male mating behavior to uncover new ways to suppress mosquito populations.

“We’ve become very interested in studying many aspects of behavior in Aedes aegypti because these mosquitoes impact the health of so many people,” Montell said. “There is a pandemic every year from mosquito-borne diseases.”

The ICB is an Army-sponsored University Affiliated Research Center led by the University of California, Santa Barbara, in collaboration with the Massachusetts Institute of Technology, the California Institute of Technology and partners from the Army and industry. Interdisciplinary teams of biologists, chemists, physicists, psychologists, physicians and engineers develop biologically inspired, revolutionary technological innovations in systems and synthetic biology, bio-enabled materials and cognitive neuroscience.

Visit the laboratory's Media Center to discover more Army science and technology stories

 

As the Army’s national research laboratory, ARL is operationalizing science to achieve transformational overmatch. Through collaboration across the command’s core technical competencies, DEVCOM leads in the discovery, development and delivery of the technology-based capabilities required to make Soldiers more successful at winning the nation’s wars and come home safely. DEVCOM Army Research Laboratory is an element of the U.S. Army Combat Capabilities Development Command. DEVCOM is a major subordinate command of the Army Futures Command.

 

Best of both worlds: New organic–inorganic gas sensors for better air quality monitoring


Scientists develop novel gas sensors with improved detection sensitivity and durability by combining organic and inorganic materials

Peer-Reviewed Publication

INCHEON NATIONAL UNIVERSITY

New Organic–Inorganic Gas Sensors for Better Air Quality Monitoring 

IMAGE: IN A NEW STUDY, RESEARCHERS FROM KOREA HAVE DEVISED A HIGH-PERFORMANCE AND DURABLE GAS SENSOR USING A COMBINATION OF AN ORGANIC POLYMER AND INORGANIC GAS SENSING MATERIAL view more 

CREDIT: ALEXANDR PODVALNY ON PEXELS

With air pollution on the rise, especially in densely populated urban areas, testing for air quality and the presence of pollutant gases, such as carbon dioxide, nitrogen dioxide (NO2), and carbon monoxide, have become more important than ever. Sensitive gas sensing and monitoring technologies are, therefore, a pressing need. 

Of much recent research interest in this field are the novel organic field-effect transistor-based (OFET) sensors, which are highly sensitive, flexible, and lightweight, opening doors to portable gas sensors even on e-skins. However, OFETs are unstable, and therefore not durable, at room temperature. This limits their applicability and makes them inferior to existing inorganic sensors, which nonetheless, do not possess any of the flexibility and light weight of organic sensors.

Bridging the organic–inorganic gap, scientists from Incheon National University, Korea, led by Prof. Yeong Don Park, have created hybrid OFETs using a organic conjugated polymer and variations of an inorganic nanoporous material, zeolite. Their study was made available online on 6 April 2021 and will be published in Volume 420 Part 1 of Chemical Engineering Journal on 15 September 2021.

“The high degree of porosity in zeolite results in an exceptionally high specific surface area and, in turn, a strong adsorption response for small gas molecules. This also helps it adsorb the molecules in air that oxidize (react with) the gas sensor to destabilize it and reduce its durability.” explains Prof. Park. Their material boasts not only high durability, but also high sensitivity.

The team fabricated two OFET-based NOsensors using a combination of the conjugated polymer, poly(3-hexylthiophene) (P3HT) and one of two zeolite materials, PST-11 or Omega. They examined the sensing performances of both OFETs when exposed to NOgas. The hybridization provided the polymer with an orderly structure which in turn led to efficient interactions with the gas molecules and, consequently, high sensitivity. Among the two, the scientists observed that the PST-11–P3HT film was more sensitive to NOthan the Omega–P3HT film due to a larger specific surface area.

Overall, Prof. Park explains: “Our approach represents a new way of conceptualizing the design and development of sensors. If our research is refined further, people can easily detect harmful gases in real time.” Speaking of his vision, he says: “Our devices can be integrated with wearable devices such as smart watches and e-skins to allow people to know about air pollution levels in areas other than industrial sites.”

While a pollution-free world is our end goal, it certainly wouldn’t hurt to stay safe while we get there.

 

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Reference

Authors: Eun Hye Kwon (1), Hyejin An (2), Min Bum Park (1), Min Kim (2) and Yeong Don Park (1)

Title of original paper: Conjugated polymer–zeolite hybrids for robust gas sensors: Effect of zeolite surface area on NO2 sensing ability

Journal: Chemical Engineering Journal

DOI: 10.1016/j.cej.2021.129588

Affiliations:

(1) Incheon National University, Korea  

(2) Jeonbuk National University, Korea

 

About Incheon National University

Incheon National University (INU) is a comprehensive, student-focused university. It was founded in 1979 and given university status in 1988. One of the largest universities in South Korea, it houses nearly 14,000 students and 500 faculty members. In 2010, INU merged with Incheon City College to expand capacity and open more curricula. With its commitment to academic excellence and an unrelenting devotion to innovative research, INU offers its students real-world internship experiences. INU not only focuses on studying and learning but also strives to provide a supportive environment for students to follow their passion, grow, and, as their slogan says, be INspired.

Website: http://www.inu.ac.kr/mbshome/mbs/inuengl/index.html

 

About the authors

Professor Yeong Don Park focuses on research on the fabrication and characterization of conductive polymer-based devices, and Professor Minbum Park conducts research on zeolite’s gas adsorption. Together, they fuse two different research fields of organic and inorganic matter; this synergistic effect gives rise to excellent, high-quality, and innovative research!

Study identifies possible antidote for club drug GHB overdose

Diclofenac blocks passage of GHB into the brain; other NSAIDs, including ibuprofen, may also limit toxicity of GHB, University at Buffalo researchers find

Peer-Reviewed Publication

UNIVERSITY AT BUFFALO

BUFFALO, N.Y. – Diclofenac and other non‐steroidal anti‐inflammatory drugs (NSAIDs) may limit the passage of gamma hydroxybutyric acid (a narcolepsy medication and illicit party drug commonly known as GHB) to the brain, decreasing the potential for fatal overdose, according to a University at Buffalo study.

The research found that treatment with diclofenac after taking GHB led to decreased concentrations of GHB in the brain and an improved respiration. The study, completed in animal models, was published in Biopharmaceutics & Drug Disposition. Previous studies completed by the UB researchers found that the NSAIDs ibuprofen and ketoprofen also affected the movement of GHB in the body.

GHB is approved for a number of clinical uses, including the treatment of narcolepsy, a chronic sleep disorder, and alcoholism. However, GHB prescriptions are limited due to its high potential for abuse as a club and date-rape drug. At high doses, the drug can cause amnesia, drowsiness and depressed breathing. There are currently no approved antidotes for GHB overdose. 

“The therapeutic utility of GHB in the treatment of narcolepsy [as Xyrem] has been overshadowed by its high prevalence of abuse. The abuse of GHB – known as Fantasy, Liquid Ecstasy and G – carries the risk of severe adverse effects including sedation, respiratory depression, hypothermia, coma and death,” says Marilyn Morris, PhD, SUNY Distinguished Professor and chair of the Department of Pharmaceutical Sciences in the UB School of Pharmacy and Pharmaceutical Sciences.

“Current treatment of GHB overdose is limited to supportive care. My laboratory has identified MCT1 inhibitors as a treatment strategy to prevent death after GHB overdoses. In this research, we identified the NSAID diclofenac as a MCT1 inhibitor and demonstrated its effectiveness as a potential antidote for GHB overdose. Also, our findings significantly suggest that diclofenac and other NSAIDs may decrease the effectiveness of Xyrem used in the treatment of narcolepsy.”  

Additional investigators include first author, UB alumna and former graduate student in Morris’ lab Vivian Rodriguez‐Cruz, PhD, research scientist at Eli Lilly and Company; and Tianjing Ren, PhD, postdoctoral researcher in the UB School of Pharmacy and Pharmaceutical Sciences.

Commonly sold under the brand name Voltaren, diclofenac is prescribed to treat pain and inflammation. Morris’ lab has found that some NSAIDs can block tissue uptake of drugs by monocarboxylate transporters (MCTs), a family of proteins that transport molecules across biological membranes, including the blood‐brain barrier, which protects the brain from toxins and pathogens circulating in the blood while allowing for the passage of nutrients.

GHB relies on MCTs for transport throughout the body, making the study of the inhibition of MCTs as an antidote a focus of Morris’ lab. 

The recent study sought to understand the impact diclofenac has on GHB toxicity by measuring the effect of their interaction on respiratory depression – the main cause of death following GHB overdose.

Diclofenac was found to inhibit the brain uptake of GHB by MCT1, the only monocarboxylate transporter present at the blood‐brain barrier, resulting in a reversal of respiratory depression after GHB overdose. 

 

The Hobbit’s bite gets a stress test


Stone tools may have allowed Homo floresiensis to eat their meals with less chewing effort than earlier hominins.

Peer-Reviewed Publication

DUKE UNIVERSITY

The skull of Homo floresiensis may have been under greater strain than the skulls of its australopith cousins when it chewed its food, putting it at greater risk than earlier human relatives of dislocating its jaw. 

IMAGE: A COMPUTER SIMULATION OF A HOMO FLORESIENSIS CRANIUM SHOWS THE PATTERN OF STRESS AND STRAIN IN THE BONES OF THE FACE DURING BITING. AREAS UNDER HIGH STRAIN ARE SHOWN IN WHITE, PINK AND RED. view more 

CREDIT: PLEASE CREDIT LEDOGAR LAB, DUKE UNIVERSITY

DURHAM, N.C. -- If you’ve ever suffered from a sore jaw that popped or clicked when you chewed gum or crunched hard foods, you may be able to blame it on your extinct ancestors.

That’s according to a Duke University-led study of the chewing mechanics of an ancient human relative called Homo floresiensis, which inhabited the Indonesian island of Flores before our species arrived there some 50,000 years ago.

Not much more than three feet tall, the hominin’s diminutive size earned it the nickname “the Hobbit,” after the characters in J.R.R. Tolkien’s “The Lord of the Rings.” For the new study, which was published Aug. 13 in the journal Interface Focus, the researchers wanted to understand how the Hobbit’s skull behaved while it ate its food.

However, thousands of years of fossilization had left its skull -- the only one that has been found so far -- damaged and misshapen. Before the researchers could test it out, they had to restore it as close to its original shape as possible. Collaborators at Italy’s University of Bologna created a 3D virtual model, built from X-ray CT scans, digitally filling in the missing pieces to reconstruct what the skull of Homo floresiensis might have looked like when it roamed the island some 100,000 to 60,000 years ago.

From that, they used computer simulations and a technique called finite element analysis to give the virtual skull characteristics that mimic the real thing, such as the stiffness of the bones and the pulling action of the muscles. Then they had the virtual skull chomp down with its back teeth -- premolars and molars -- and analyzed the forces at work with each bite, essentially subjecting it to a digital crash test.

The researchers mapped the strains within their digital model of the Hobbit’s facial bones during biting, comparing the results to similar simulations for earlier human relatives called australopiths that lived some two to three million years ago in Africa, along with chimpanzees and humans living today.

The team determined that the Hobbit’s bite could have exerted around 1300 Newtons of force, comparable to the chomping power of modern humans and several of our extinct cousins. But had it bitten down too vigorously on a hard nut or a tough hunk of meat, the findings suggest Homo floresiensis would have been at greater risk than our earlier human kin of straining its facial bones, or dislocating the joint where the lower and upper jaws meet.

“We don't really know what Homo floresiensis ate,” said first author Rebecca Cook, a doctoral student in evolutionary anthropology at Duke. Patterns of wear on the teeth, combined with pygmy elephant bones and other animal remains unearthed from the same cave where the Hobbit was found suggest that it ate at least some meat.

But the results suggest that exceedingly hard or tough foods, which would have been no problem for an australopith to gnaw on or crack open, might have given the Hobbit a TMJ headache.

“Similar patterns are observed in modern humans,” Cook said.

Millions of years of human evolution gave us smaller teeth and more lightweight skulls, because cooking our food and slicing and pounding it with stone tools, and probably also eating meat, made having overbuilt skulls unnecessary.

But years after the Hobbit’s discovery its facial features remain a puzzle. Its skull had a curious mix of traits, some of which -- like its heavyset lower jaw -- are similar to our earlier and more ape-like ancestors, while others -- like its small delicate face -- resemble humans today.

“This can make it confusing as to where this species falls on the family tree of hominin evolutionary relationships,” Cook said.

The new study suggests this shift to smaller faces, weaker bites and achey jaws evolved early, before the common ancestors of Homo floresiensis and modern humans went their separate ways.

Justin Ledogar, Duke researcher and senior author of the study, says the next step is to do similar analyses on earlier members of the genus Homo, including Homo erectus. The first known hominin to use fire and cook food, this species also had smaller teeth, jaws and faces than earlier hominins, and is thought by some to be the ancestor of Homo floresiensis.

The researchers say the work could help answer lingering questions about where Homo floresiensis came from, how it lived and how it fits into the human evolutionary tree.

“This study is just one small piece of a much larger puzzle,” Cook said.

This research was funded by the American Association of Physical Anthropology and Duke University, and by grants from the European Union’s Horizon 2020 Research and Innovation Programme (724046 SUCCESS) and the U.S. National Science Foundation (NSF-BCS-0725126).

CITATION: "The Cranial Biomechanics and Feeding Performance of Homo Floresiensis," Rebecca W. Cook, Antonino Vazzana, Rita Sorrentino, Stefano Benazzi, Amanda L. Smith, David S. Strait and Justin A. Ledogar. Interface Focus, Aug. 13, 2021. DOI: 10.1098/rsfs.2020.0083