Led by Angel Yanagihara, associate research professor at the UH Manoa School of Ocean and Earth Science and Technology (SOEST) and the John A. Burns School of Medicine, researchers at the UH at Manoa have been carefully tracking local box jellies for over 20 years. While the monthly shoreline aggregations are understood to occur like clockwork 8-10 days after each full moon, with jelly forecasts included on the local news, mysteries have remained: Why are they appearing at this particular part of the lunar cycle? Where do these box jellies come from and where are they found the rest of the lunar cycle? Why has this become a monthly problem in only the last 30 years?

With the new study, the team provided in-depth answers based upon cutting-edge oceanographic approaches including nightlong off shore vessel tracking, computer modeling of local currents and side scan sonar, as well as fundamental field ecology methods and anatomical microscopy.

The senior scientist team of Yanagihara and SOEST oceanography professor Margaret McManus conceived of and began this collaborative study ten years ago starting from monthly box jelly census data collected by the Yanagihara Lab from 1997 to the present.

“We found that the dangerous monthly shoreline appearance of the Hawaiian Box Jellyfish, correlates with the specific nights of the lunar month — referred to as Kaloa in the Hawaiian calendar — with a critical number of hours of darkness after sunset and before moonrise,” said Yanagihara. “We also discovered that all the box jellies comprising the shoreline aggregation were actively spawning.”

Based on studies of thousands of beached box jellies, Yanagihara found that the gonads were all replete with gametes or freshly spent — meaning they were nearshore to reproduce.

“The period of the lunar cycle with a key number of hours of darkness or the ‘absence of light’ cues mature animals to specifically swim to the shore line to spawn,” said Yanagihara. “Further, as divers tracking the migration in the water, we faced a strong south easterly (Diamond Head) current that the box jellies swam successfully perpendicular to but, we divers with tanks and big cameras could not. Their swimming speed and power was impressive!”

With McManus’ oceanographic analysis, the researchers hypothesize that jellies are in the lee of Diamond Head Crater for the rest of the lunar cycle, benefiting from the shelter and food provided by the persistent eddy in the study area, which appears to be the “source point” for the jellyfish or where the box jellies come from.

The UH scientists are addressing issues of importance and concern to residents and tourists alike who enjoy Hawai’i’s coastal waters as well as of great importance to other tropical islands with local populations of this same species Alatina alata. While there are over 40 species of box jellies world wide, Alatina alata is the only species that exhibits this clockwork lunar spawning migration behavior. The team also studied Alatina alata migrations in Saipan, CMNI and Puerto Rico and Key West, FL. This research revealed the unique life cycle involving specific shoreline bathymetry features which support persistent anticyclonic eddy features as well as the lunar trigger for spawning and will allow the team to further investigate other O’ahu locations where box jellies have not been observed historically but have now become more common such as Pupukea and Kailua.

“This work is very important to the State in terms of planning and tourism as well as improved signage, public awareness and dissemination of evidence-based jellyfish sting care,” said Yanagihara.

In the future, the team hopes to continue these studies to model other offshore bay features adjacent to box jelly beaching events and to track population numbers which can become emerging public health concerns for ocean swimmers and beach goers. Specifically, research efforts are being designed to inform and predict, as well as, to help guide policies to restore food web balance to keep box jelly numbers in check in Hawai’i and other tropical localities where Alatina alata also represent a concern for beach goers.

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Materials provided by University of Hawaii at Manoa. Original written by Marcie Grabowski. Note: Content may be edited for style and length.

Producing the extraordinary bursts in space are celestial bodies such as neutron, or collapsed, stars called magnetars (magnet + star) enclosed in extreme magnetic fields. These fields are so strong that they turn the vacuum in space into an exotic plasma composed of matter and anti-matter in the form of pairs of negatively charged electrons and positively charged positrons, according to quantum electrodynamic (QED) theory. Emissions from these pairs are believed to be responsible for the powerful fast radio bursts.

Pair plasma

The matter-antimatter plasma, called “pair plasma,” stands in contrast to the usual plasma that fuels fusion reactions and makes up 99% of the visible universe. This plasma consists of matter only in the form of electrons and vastly higher-mass atomic nuclei, or ions. The electron-positron plasmas are composed of equal mass but oppositely charged particles that are subject to annihilation and creation. Such plasmas can exhibit quite different collective behavior.

“Our laboratory simulation is a small-scale analog of a magnetar environment,” said physicist Kenan Qu of the Princeton Department of Astrophysical Sciences. “This allows us to analyze QED pair plasmas,” said Qu, first author of a study showcased in Physics of Plasmas as a Scilight, or science highlight, and also first author of a paper in Physical Review Letters that the present paper expands on.

“Rather than simulating a strong magnetic field, we use a strong laser,” Qu said. “It converts energy into pair plasma through what are called QED cascades. The pair plasma then shifts the laser pulse to a higher frequency,” he said. “The exciting result demonstrates the prospects for creating and observing QED pair plasma in laboratories and enabling experiments to verify theories about fast radio bursts.”

Laboratory-produced pair plasmas have previously been created, noted physicist Nat Fisch, a professor of astrophysical sciences at Princeton University and associate director for academic affairs at PPPL who serves as principle investigator for this research. “And we think we know what laws govern their collective behavior,” Fisch said. “But until we actually produce a pair plasma in the laboratory that exhibits collective phenomena that we can probe, we cannot be absolutely sure of that.

Collective behavior

“The problem is that collective behavior in pair plasmas is notoriously hard to observe,” he added. “Thus, a major step for us was to think of this as a joint production-observation problem, recognizing that a great method of observation relaxes the conditions on what must be produced and in turn leads us to a more practicable user facility.”

The unique simulation the paper proposes creates high-density QED pair plasma by colliding the laser with a dense electron beam travelling near the speed of light. This approach is cost-efficient when compared with the commonly proposed method of colliding ultra-strong lasers to produce the QED cascades. The approach also slows the movement of plasma particles, thereby allowing stronger collective effects.

“No lasers are strong enough to achieve this today and building them could cost billions of dollars,” Qu said. “Our approach strongly supports using an electron beam accelerator and a moderately strong laser to achieve QED pair plasma. The implication of our study is that supporting this approach could save a lot of money.”

Currently underway are preparations for testing the simulation with a new round of laser and electron experiments at SLAC. “In a sense what we are doing here is the starting point of the cascade that produces radio bursts,” said Sebastian Meuren, a SLAC researcher and former postdoctoral visiting fellow at Princeton University who coauthored the two papers with Qu and Fisch.

Evolving experiment

“If we could observe something like a radio burst in the laboratory that would be extremely exciting,” Meuren said. “But the first part is just to observe the scattering of the electron beams and once we do that we’ll improve the laser intensity to get to higher densities to actually see the electron-positron pairs. The idea is that our experiment will evolve over the next two years or so.”

The overall goal of this research is understanding how bodies like magnetars create pair plasma and what new physics associated with fast radio bursts are brought about, Qu said. “These are the central questions we are interested in.”

This joint work was supported by National Nuclear Security Agency (NNSA) grants awarded to Princeton University through the Department of Astrophysical Sciences and by DOE grants awarded to Stanford University.

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Materials provided by DOE/Princeton Plasma Physics Laboratory. Original written by John Greenwald. Note: Content may be edited for style and length.

Now researchers at MIT have been able to study exactly what happens as these crystal grains form during an extreme deformation process, at the tiniest scales, down to a few nanometers across. The new findings could lead to improved ways of processing to produce better, more consistent properties such as hardness and toughness.

The new findings, made possible by detailed analysis of images from a suite of powerful imaging systems, are reported today in the journal Nature Materials, in a paper by former MIT postdoc Ahmed Tiamiyu (now assistant professor at the University of Calgary); MIT professors Christopher Schuh, Keith Nelson, and James LeBeau; former student Edward Pang; and current student Xi Chen.

“In the process of making a metal, you are endowing it with a certain structure, and that structure will dictate its properties in service,” Schuh says. In general, the smaller the grain size, the stronger the resulting metal. Striving to improve strength and toughness by making the grain sizes smaller “has been an overarching theme in all of metallurgy, in all metals, for the past 80 years,” he says.

Metallurgists have long applied a variety of empirically developed methods for reducing the sizes of the grains in a piece of solid metal, generally by imparting various kinds of strain through deforming it in one way or another. But it’s not easy to make these grains smaller.

The primary method is called recrystallization, in which the metal is deformed and heated. This creates many small defects throughout the piece, which are “highly disordered and all over the place,” says Schuh, who is the Danae and Vasilis Salapatas Professor of Metallurgy.

When the metal is deformed and heated, then all those defects can spontaneously form the nuclei of new crystals. “You go from this messy soup of defects to freshly new nucleated crystals. And because they’re freshly nucleated, they start very small,” leading to a structure with much smaller grains, Schuh explains.

What’s unique about the new work, he says, is determining how this process takes place at very high speed and the smallest scales. Whereas typical metal-forming processes like forging or sheet rolling, may be quite fast, this new analysis looks at processes that are “several orders of magnitude faster,” Schuh says.

“We use a laser to launch metal particles at supersonic speeds. To say it happens in the blink of an eye would be an incredible understatement, because you could do thousands of these in the blink of an eye,” says Schuh.

Such a high-speed process is not just a laboratory curiosity, he says. “There are industrial processes where things do happen at that speed.” These include high-speed machining; high-energy milling of metal powder; and a method called cold spray, for forming coatings. In their experiments, “we’ve tried to understand that recrystallization process under those very extreme rates, and because the rates are so high, no one has really been able to dig in there and look systematically at that process before,” he says.

Using a laser-based system to shoot 10-micrometer particles at a surface, Tiamiyu, who carried out the experiments, “could shoot these particles one at a time, and really measure how fast they are going and how hard they hit,” Schuh says. Shooting the particles at ever-faster speeds, he would then cut them open to see how the grain structure evolved, down to the nanometer scale, using a variety of sophisticated microscopy techniques at the MIT.nano facility, in collaboration with microscopy specialists.

The result was the discovery of what Schuh says is a “novel pathway” by which grains were forming down to the nanometer scale. The new pathway, which they call nano-twinning assisted recrystallization, is a variation of a known phenomenon in metals called twinning, a particular kind of defect in which part of the crystalline structure flips its orientation. It’s a “mirror symmetry flip, and you end up getting these stripey patterns where the metal flips its orientation and flips back again, like a herringbone pattern,” he says. The team found that the higher the rate of these impacts, the more this process took place, leading to ever smaller grains as those nanoscale “twins” broke up into new crystal grains.

In the experiments they did using copper, the process of bombarding the surface with these tiny particles at high speed could increase the metal’s strength about tenfold. “This is not a small change in properties,” Schuh says, and that result is not surprising since it’s an extension of the known effect of hardening that comes from the hammer blows of ordinary forging. “This is sort of a hyper-forging type of phenomenon that we’re talking about.”

In the experiments, they were able to apply a wide range of imaging and measurements to the exact same particles and impact sites, Schuh says: “So, we end up getting a multimodal view. We get different lenses on the same exact region and material, and when you put all that together, you have just a richness of quantitative detail about what’s going on that a single technique alone wouldn’t provide.”

Because the new findings provide guidance about the degree of deformation needed, how fast that deformation takes place, and the temperatures to use for maximum effect for any given specific metals or processing methods, they can be directly applied right away to real-world metals production, Tiamiyu says. The graphs they produced from the experimental work should be generally applicable. “They’re not just hypothetical lines,” Tiamiyu says. For any given metals or alloys, “if you’re trying to determine if nanograins will form, if you have the parameters, just slot it in there” into the formulas they developed, and the results should show what kind of grain structure can be expected from given rates of impact and given temperatures.

The research was supported by the U.S. Department of Energy, the Office of Naval Research, and the Natural Sciences and Engineering Research Council of Canada.

The team combined genetic and biochemical studies to show how freshwater cyanobacteria produce the potent neurotoxin called guanitoxin. This discovery revealed that guanitoxin-producing cyanobacteria are more prevalent than originally known in the United States, opening the possibility for new molecular diagnostic testing to better inform and protect the public from this natural freshwater toxin. Findings were described in a paper published in the Journal of the American Chemical Society on May 18, 2022.

The paper also “shows guanitoxin being produced in freshwater bodies that have undergone past very toxic events,” said study lead author Stella Lima, a former PhD student at the University of São Paulo and visiting scholar at Scripps Oceanography.

Guanitoxin is one of the most potent neurotoxins made by cyanobacteria that actually has a similar mechanism of action to pesticides and chemical warfare agents, said Timothy Fallon, a Scripps postdoctoral scientist in the laboratory of Scripps marine chemical biologist Bradley Moore, where Lima was a visiting scholar.

Harmful algal blooms (HABs) form in lakes and ponds when cyanobacteria, otherwise known as blue-green algae, become abundant. These freshwater HABs produce different cyanotoxins, which can harm nearby animals and people. Depending on the cyanotoxin involved, exposed people exhibit symptoms such as stomach pain, headache, vomiting, liver damage or neurological impairment, according to federal health officials. Over the years, many regions have declared emergencies and issued “do not drink” advisories. Pet and animal deaths have also been reported after the animals came in contact with affected water.

Freshwater HABs can cause myriad social and economic problems for communities and are a problematic public health issue, said Lima. Testing and monitoring for certain cyanotoxins, such as microcystin, cylindrospermopsin, saxitoxin and anatoxin-a, occur because methods are available to do so, but despite the fact that guanitoxin is the second most toxic cyanotoxin, “no one’s looking for it” because the right methods aren’t available for detection and monitoring, Lima added.

As a PhD student in 2016, Lima found a set of genes she suspected was responsible for making guanitoxin by a cyanobacterium isolated from a large freshwater bloom in Brazil. The strain was isolated from the Tapacurá reservoir in Pernambuco, Brazil and has been maintained and cultivated by Marli Fiore, Lima’s former PhD advisor and co-author of the study

After this discovery, Lima looked for a partnership to confirm her suspicion. So, in 2018 she traveled to UC San Diego to work with Moore, who had established the first biochemical studies on guanitoxin back in the early 1990s. The team of scientists worked together to establish the precise functions of all nine enzymes that convert an ordinary amino acid to a neurotoxin, Lima said.

After discovering the genes involved in the production of guanitoxin and carefully validating their functions, researchers searched through thousands of samples from publically available environmental data for the guanitoxin biosynthetic genes.

The researchers were able to detect toxin genes for guanitoxin in environmental hotspots in the United States in populated areas, said Moore, who is a co-corresponding author of the study. The two areas of concern, where the toxin genes were regularly detected for guanitoxin, were in Lake Erie near Toledo, Ohio and in Lake Mendota, Wisconsin.Other areas of detection include the Amazon River in Brazil, the Columbia River in Oregon and the Delaware River in Delaware.

“We found these genes in lots of different fresh water sources, but nobody has looked for or monitored for this particular toxin environmentally,” said Shaun McKinnie, a chemistry and biochemistry assistant professor at UC Santa Cruz and former postdoctoral scholar in the Moore Lab, who contributed to the study.

“Here’s this neurotoxic potential in these lakes that people use recreationally, but this toxin has gone under the radar until our work,” Fallon said.

Moore said follow-up work should include fieldwork to detect other areas where guanitoxin may be produced.

Cyanobacterial blooms are becoming more and more prevalent in the United States and worldwide, mostly because of climate change and the introduction of fertilizers and other chemicals related to farming into bodies of water.

While HABs can be visible on the surface of freshwater bodies, the federal Environmental Protection Agency (EPA) states “cyanotoxins can be present before and after blooms are visible. Therefore, it is recommended that cyanotoxin levels be confirmed through laboratory testing of the water.”

“Now that we figured out the guanitoxin pathway at the genomic level, we can also give additional pieces of information to say: ‘This is a safe body of water, or this is a less safe body of water; Does this have the ability to become toxic and can we predict toxic events?'” McKinnie said.

The researchers have filed a provisional patent application based on the concept of using the guanitoxin biosynthetic gene sequences they identified in the lab and applying molecular diagnostics using those sequences to find the genes in the environment.

In addition to Lima, Fallon, Moore, Fiore, and McKinnie, other study co-authors include Endrews Delbaje, Ernani Pinto and Felipe Dörr from the University of São Paulo; former Moore Lab scientist Hanna Luhavaya; current Scripps Oceanography PhD student Steffaney Wood; UC Santa Cruz researchers Jennifer Cordoza, Austin Hopiavuori, and Jackson Baumgartner; Jonathon Chekan from University of North Carolina Greensboro; Danillo Alvarenga from the University of Copenhagen; and Augusto Etchegaray from the Pontifical Catholic University of Campinas in Brazil.

The study was funded by the National Institute of Environmental Health Sciences, the Sao Paulo Research Foundation, and the National Council for Scientific and Technological Development. Other funding was from the Simons Foundation Fellowship of the Life Sciences Research Foundation; the Brazilian Federal Agency for the Support Evaluation of Graduate Education; startup funding and a Faculty Research Grant from UC Santa Cruz.

Dr. Swann is a leading expert in epilepsy research and a few years back, his team’s pioneering discoveries resulted in an FDA-approved treatment for severe epilepsy among tuberous sclerosis patients. He and his team have had a longstanding interest and experience in studying infantile spasms, an epileptic disorder diagnosed in roughly 2500 babies in the United States each year.

Early-life brain injuries reduce IGF-1 levels and impair the IGF-1 signaling pathway

“It has been previously reported that IS patients with preexisting brain abnormalities have low levels of IGF-1 in their cerebrospinal fluid and based on that study, we were interested in investigating if IGF-1 levels were altered in the brains of IS animals and patients,” Swann said.

For their investigations, the team used a well-established method to induce spontaneous epileptic spasms in rodents. This methodology, developed in 2008 in the Swann lab, involves chronic infusion of tetrodotoxin (TTX) into the cortex of the infant rat brain, which causes injury at the infusion site and results in spasms that are virtually identical to the those seen in IS patients.

“As is expected after a brain injury, we saw an increase in IGF-1 levels in the non-neuronal support cells (aka glia) at the site of TTX infusion. However, we were most intrigued by the remarkable and widespread decrease in IGF-1 expression in cortical neurons in brain regions adjacent to or further away from the site of TTX injection — a phenomenon that had never been reported before,” Swann said.

Next, the team studied resected cortical tissue from IS patients who had prior perinatal strokes and had undergone surgery to control their intractable seizures. The results were remarkably similar to what they had seen in IS animals.

“More importantly, we found this reduction in cortical levels of IGF-1 had significant consequences in IS animal models because it dampened the overall activity of the IGF-1 molecular signaling pathways that regulate many important biological processes involved in early brain development and neuronal function,” said Dr. Carlos Ballester-Rosado, a postdoctoral associate in the Swann lab and first author of the study.

An IGF-1 analog eliminates infantile spasms in animals

To determine if increasing IGF-1 levels in the cortex of IS animals could ameliorate spasms, the team used a smaller version of IGF-1 that can cross the blood-brain barrier with greater ease than the full-length hormone. The IGF-1 tripeptide they tested is a natural by-product of IGF-1 breakdown that is found normally in the brain. Moreover, this analog has been previously demonstrated to successfully reverse behavioral defects in animal models of other neurodevelopmental disorders such as Rett syndrome and Phelan-McDermid syndrome.

“Using several lines of evidence, we first confirmed that this IGF-1 tripeptide was capable of activating the IGF-1 signaling cascade in mice,” Swann said. “We then found — to our astonishment — that administration of IGF-1 successfully eliminated spasms and an IS-specific chaotic brain activity pattern called hypsarrhythmia in most of the IS animals. We are excited because these findings raise the tantalizing possibility that this IGF-1 analog can be used to treat IS patients in the future.”

Others involved in the study are John Le, Trang Lam, Carrie Mohila, Sandi Lam, Anne Anderson and James Frost. The authors are affiliated with one or more of the following institutions: Cain Foundation Laboratories, the Jan and Dan Duncan Neurological Research Institute at Texas Children’s Hospital and Baylor College of Medicine. The study was funded by CURE Epilepsy’s Infantile Spasms Initiative, grants from the National Institute of Health (RO1 NS018309, RO1 NS105913 and R61/R33 NS112553) and Intellectual and Developmental Disabilities Centers (1U54 HD083092) from the Eunice Kennedy Shriver National Institute of Child Health and Human Development.

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Materials provided by Texas Children’s Hospital. Original written by Rajalaxmi Natarajan. Note: Content may be edited for style and length.

That’s because adding iodide to a water treatment reactor that uses ultraviolet (UV) light and sulfite destroys up to 90% of carbon-fluorine atoms in PFAS forever chemicals in just a few hours, reports a new study led by environmental engineering researchers at UC Riverside. The addition of iodide accelerates the speed of the reaction up to four times, saving energy and chemicals.

“Iodide is really doing some substantial work,” said corresponding author Jinyong Liu, an assistant professor of chemical and environmental engineering. “Not only does it speed up the reaction but it also allows the treatment of a ten times higher concentrations of PFAS, even some very recalcitrant structures.”

Liu’s lab has been working on ways to destroy PFAS through photochemical reactions since 2017. The new method has already attracted interest from industry and Liu’s group is partnering with companies to conduct pilot tests.

Synthetic chemicals known as PFAS contain multiple very strong carbon-fluorine bonds. Widespread use of these nonbiodegradable compounds in countless products since the 1940s has contaminated water supplies across America, with various negative health effects on human and animals. Because the carbon-fluorine bond is very hard to break, PFAS pass through most water treatment systems unchanged.

Photochemical degradation by UV light and sulfite (SO₃²⁻) is, to date, one the most effective ways to break PFAS down. The original process used a lot of electricity because the chemical reactions occurred slowly. It also left multiple carbon-fluorine bonds remaining in the degradation products, with unknown health effects.

Last year, the researchers reported that oxidation treatments before and after the UV/sulfite treatment can achieve almost 100% destruction of carbon-fluorine bonds in various major PFAS pollutants.

In the new work, the researchers added iodide to the UV/sulfite system to treat a particularly stubborn four-carbon PFAS molecule called perfluorobutane sulfonate (PFBS), which degrades poorly in the original UV/sulfite setting. The iodide accelerated the reaction and completely removed PFBS within 24 hours.

As expected, the UV/sulfite+iodide system also degraded other PFAS, such as the frequently reported eight-carbon PFOA and PFOS, with ease. The addition of iodide also enabled the system to destroy concentrated PFAS in brine solution, which is a practical challenge for groundwater remediation. Ion-exchange systems are used to clean the groundwater, but the PFAS chemicals captured in the resin need to be washed out and destroyed in a cost-effective way.

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Materials provided by University of California – Riverside. Original written by Holly Ober. Note: Content may be edited for style and length.

The study, led by UBC faculty of forestry member Arthur Bass and using data generated by the Strategic Salmon Health Initiative, assessed dozens of pathogens in thousands of Chinook and Coho salmon sampled over a decade along the B.C. coast.

For the first time ever, researchers were able to identify the pathogens most closely linked to survival of free-ranging Pacific salmon in the ocean: Tenacibaculum maritimum, a bacterium that causes ulcerative disease in salmon and other cultured marine fish worldwide; and piscine orthoreovirus (PRV), a virus that causes disease in Pacific and Atlantic salmon worldwide, but whose impact on salmon in B.C. is vigorously debated.

“This is the first empirical evidence that PRV is negatively impacting wild Pacific salmon in B.C.,” says Dr. Bass, a postdoctoral researcher at UBC’s Pacific Salmon Ecology Conservation Lab. “These two pathogens are common on salmon farms in B.C., and recent studies provide evidence of transmission from farms to wild salmon.”

“Many studies show that high ocean temperatures impact salmon survival, but this new research shows that in some cases pathogen presence can be more important,” notes the study senior author Kristin Miller-Saunders, a molecular genetics scientist with Fisheries and Oceans Canada (DFO) and an adjunct professor of fisheries at UBC.

The research was funded by the Pacific Salmon Foundation, Genome BC and DFO and published today in FACETS.

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Materials provided by University of British Columbia. Note: Content may be edited for style and length.