Particle trio exceeds expectations at LHC

Illustration Credit: ATLAS Experiment/CERN

The ATLAS experiment measured more than expected of a trio of particles in the aftermath of proton collisions. The results will refine physicists’ understanding of our universe at the subatomic level.

The ATLAS experiment has confirmed that a trio of particles – a top-antitop quark pair and a W boson –occurs more frequently than expected in the wake of proton-proton collisions inside the Large Hadron Collider (LHC). 

The process that creates these three particles post impact is quite rare: Only one out of every 50,000 collisions at the LHC produces the trio, known as ttW. After popping into existence, top quarks and W bosons are short lived and decay almost immediately, so the team identified ttW events based on the electrons and muons they decay into. 

Members of the ATLAS group at the Department of Energy's SLAC National Accelerator Laboratory have spent the last three years completing a complex analysis to measure the process, including developing novel methods to estimate and remove background and detector effects to maximize the accuracy and detail of the analysis of the measurement. The results will help researchers better test theories of elementary particle physics as well as help experimentalists studying other particle physics processes.

Massive Caribbean sea urchin die-off caused by parasite

In a study led by Cornell microbiology professor Ian Hewson, scientists have discovered that a parasite is behind a severe die-off of long-spined sea urchins across the Caribbean Sea, which has had devastating consequences for coral reefs and surrounding marine ecosystems.

Video Credit: Noël Heaney/Cornell University 

Scientists have discovered that a parasite is behind a severe die-off of long-spined sea urchins across the Caribbean Sea, which has had devastating consequences for coral reefs and surrounding marine ecosystems.

The long-spined sea urchins (Diadema antillarum) serve as vital herbivores that graze on algae, which if left unchecked will outcompete corals for resources and space and blanket them, block light and kill them. By feeding on algae, the sea urchins are essential to maintaining coral health and balance in the marine ecosystem.

Diadema mortalities were first reported in St. Thomas in the U.S. Virgin Islands in late January 2022. By late March, the condition was found across the Lesser Antilles, Jamaica and the Mexican Caribbean. And by June of last year, it had been detected in most of the Greater Antilles, Florida and Curacao.

Prior to an experiment designed to verify the source of infections, a healthy sea urchin was swabbed to ensure it had never been exposed to the ciliate parasite.

Scientists have been trying to identify the cause of the mysterious illness, which has led to declines of between 85% and 95% compared to pre-mortality numbers in affected areas. When sea urchins die, they lose their spines and detach from their anchors.

I’ll Have My Nano-Sized Donuts with Extra Swirls

Donut shaped skyrmions (left) show polarization swirls in one direction, while half-donut-shaped merons (right) are able to swirl in multiple directions.
Image Credit: Yu-Tsun Shao.

Swirling donuts. That’s what Yu-Tsun Shao thinks about when describing his atomic-scale materials research.

Shao, an assistant professor in the Mork Family Department of Chemical Engineering and Materials Science, aims to understand the atomic-scale behavior of donut-shaped particles that can enable low-power electronics. He has uncovered how strain and heat can shift the shape of the donut particle to give it powerful new energy-efficient and stabilizing properties. His latest work was recently published in Nature Communications.

Shao is working with skyrmions — nanometer-sized objects that resemble donut-like swirling vortexes. The skyrmions have electric polarization in the form of positive or negative charges (dipoles) that move in a continuous direction up and out from the center ‘donut hole” and down and in from the outer edge of the particle.

Not so sweet after all: are candy-striped spiders a threat to ecosystems across North America?

candy-striped spider Enoplognatha ovata
Photo Credit: Syrio (CC BY-SA 4.0)

For years, pollinator declines have been a pressing issue for ecosystem health and food security in the face of climate change and human impacts on the environment. Even in their sleep, pollinating insects cannot catch a break – for fear they’ll be taken down by a small, but mighty predator: the candy-striped spider. Research published in Ecology took a closer look into this spider’s behavior and found that the result of their stealth attacks could have substantial impacts on ecosystems.

Most likely accidentally introduced to both the East and West Coasts a little over a century ago, the candy-striped spider is a very common spider in North America. The spider's striking color varieties have attracted much research into their genetics, but before now very little was known about their behavior.

New blue light technique could enable advances in understanding nanoscale technologies

Photo Credit: Courtesy of Brown University

With a new microscopy technique that uses blue light to measure electrons in semiconductors and other nanoscale materials, a team of Brown University researchers is opening a new realm of possibilities in the study of these critical components, which can help power devices like mobile phones and laptops.

The findings are a first in nanoscale imaging and provide a workaround to a longstanding problem that has greatly limited the study of key phenomena in a wide variety of materials that could one day lead to more energy-efficient semiconductors and electronics. The work was published in Light: Science & Applications.

“There is a lot of interest these days in studying materials with nanoscale resolution using optics,” said Daniel Mittleman, a professor in Brown’s School of Engineering and author of the paper describing the work. “As the wavelength gets shorter, this becomes a lot harder to implement. As a result, nobody had ever done it with blue light until now.”

Cannabis exposures in suspected suicide attempts are on the rise

Photo Credit: Jose Luis Sanchez Pereyra

Suspected suicidal cannabis exposures have increased 17% annually, over a period of 12 years, according to a Washington State University-led analysis of U.S. poison center data.

The vast majority of the attempts, more than 92%, involved other substances in addition to cannabis, and the data cannot show a direct causal link between cannabis and suicide attempts. Still, the findings are cause for concern, the researchers said, especially since the increase was more pronounced among children and women during and after the pandemic. They reported their findings in the journal JAMA Network Open.

“This study adds to already ample evidence that cannabis use, particularly by younger people, has significant implications for mental health,” said study co-author Tracy Klein, a WSU associate professor of nursing. “We don’t have evidence that cannabis alone was the primary driver of a suicide attempt, but we do know that cannabis can worsen certain mental health conditions and increase impulsivity.”

Lithium can be obtained from hot deep water

View of the laboratory: An adsorbent based on a lithium-manganese oxide with a special crystal structure serves as a lithium-ion sieve.
Photo Credit: Dr. Monika Bäuerle, IAM-ESS / KIT

Researchers at KIT and EnBW show lithium-ion sieve for geothermal soles - lithium extraction can complement electricity generation and heat supply

Geothermal energy not only enables a sustainable supply of electricity and heat, but also a regional lithium extraction. Researchers at the Karlsruhe Institute of Technology (KIT) and EnBW have produced a lithium-ion sieve from a lithium-manganese oxide and used it to adsorb lithium from geothermal brines. The use of domestic lithium sources can help to meet the increasing demand for light metal, which is indispensable as energy storage material. The researchers reported in the journal Energy Advances, who now recognizes the work as one of the "Outstanding Paper 2022". 

A sustainable energy supply requires efficient energy storage. Lithium is indispensable - the light metal is in the batteries of many technical devices and vehicles, from smartphones to notebooks to electric cars. Demand has risen sharply worldwide in recent years. Europe is still dependent on imports. However, there are also European lithium deposits, namely thermal waters a few kilometers deep. They contain high concentrations of lithium ions. In this way, geothermal plants that extract hot water from the depths can not only be used for sustainable electricity and heat supply, but also for environmentally friendly regional lithium production.

A once-stable glacier in Greenland is now rapidly disappearing

 

The K.J.V. Steenstrup Glacier during the summer melt season in 2016.
Photo Credit: NASA/John Sonntag.

As climate change causes ocean temperatures to rise, one of Greenland’s previously most stable glaciers is now retreating at an unprecedented rate, according to a new study. 

Led by researchers at The Ohio State University, a team found that between 2018 and 2021, Steenstrup Glacier in Greenland has retreated about 5 miles, thinned about 20%, doubled in the amount of ice it discharges into the ocean, and quadrupled in velocity. According to the study, such a rapid change is so extraordinary among Greenland ice formations that it now places Steenstrup in the top 10% of glaciers that contribute to the entire region’s total ice discharge.

The study was published today in Nature Communications. 

The Steenstrup Glacier is part of The Greenland Ice Sheet, a body of ice that covers nearly 80% of the world’s largest island, which is also the single largest contributor to global sea rise from the cryosphere, the portion of Earth’s ecosystem that includes all of its frozen water. While the region plays a crucial part in balancing the global climate system, the area is steadily shrinking as it sheds hundreds of billions of tons of ice each year because of global warming.

The wound dressing that can reveal infection

The wound dressing is made of tight mesh nanocellulose, preventing bacteria and other microbes from getting in. At the same time, the material lets gases and liquid through.
Photo Credit: Olof Planthaber

A nanocellulose wound dressing that can reveal early signs of infection without interfering with the healing process has been developed by researchers at Linköping University. Their study, published in Materials Today Bio, is one further step on the road to a new type of wound care.

The skin is the largest organ of the human body. A wound disrupts the normal function of the skin and can take a long time to heal, be very painful for the patient and may, in a worst-case scenario, lead to death if not treated correctly. Also, hard-to-heal wounds pose a great burden on society, representing about half of all costs in out-patient care.

In traditional wound care, dressings are changed regularly, about every two days. To check whether the wound is infected, care staff have to lift the dressing and make an assessment based on appearance and tests. This is a painful procedure that disturbs wound healing as the scab breaks repeatedly. The risk of infection also increases every time the wound is exposed.

Concordia researchers fight shallow lake algae blooms with floating filtration technique

Photo Credit: Liz Harrell

Climate change and human activity have been putting pressure on water bodies worldwide, and Canada’s vast network of lakes is no exception. Over the past decades, increasing nutrient levels have led to a process called eutrophication, in the shallow lakes dotting Quebec’s Laurentian region north of Montreal. These changes have led to a surge in algae blooms, rendering the lakes unusable and possibly disrupting the natural ecosystem.

Restoring these lakes to a healthier condition is a complicated and expensive undertaking, but a new method being investigated by Concordia researchers in the Department of Building, Civil and Environmental Engineering may cut down on both costs and labor in an environmentally friendly way.

Writing in the journal Water, the researchers describe a system of floating geotextile filters that efficiently remove suspended solids, algae and the nutrients from a shallow lake.  While the project is still in development, the researchers say they believe it has the potential to scale up. This technology could then benefit the health of larger bodies of water such as ponds, rivers, coastal areas and bays.