Organic light-emitting diodes: the blue shines brighter and longer

Thanks to a new type of molecule, blue OLEDs should shine brighter in the future and fade less quickly.
Photo Credit: Markus Breig, KIT

Two-channel intra / intermolecular exciplex emission enables efficient deep blue electroluminescence.

Organic LEDs, or OLEDs for short, are characterized by energy efficiency and flexibility. But one challenge lies in the production of blue OLEDs - these have so far lacked luminance and stability. Researchers at the Karlsruhe Institute of Technology (KIT) and at Shanghai University have now developed a new strategy for producing efficient deep blue OLEDs: A specially produced novel molecule enables two-channel intra / intermolecular exciplex emission with electronic excitation, thereby allowing deep blue electroluminescence. The researchers report in the journal Science Advances.

Organic LEDs are already in many smartphones, tablets and large-scale TVs. They do not require additional backlighting and are therefore energy-efficient, can be produced inexpensively using thin-film technology and also work on flexible substrates, which enables flexible displays and variable room lighting solutions. An OLED (stands for: organic light-emitting diode) consists of two electrodes, at least one of which is transparent. In between are thin layers of organic semiconducting materials. The lighting is created by electroluminescence. When creating an electric field, electrons from the cathode and holes (positive charges) from the anode are injected into the organic materials that act as emitters. Electrons and holes meet there and form electron-hole pairs. These then disintegrate into their initial state and release energy that the organic materials use to emit light. All colors are created by mixing the three colors blue, green and red.

Mechanisms behind aggressive cancer metastases uncovered

A molecular chain reaction gives breast cancer cells the ability to efficiently colonize other organs.
Image Credit: National Cancer Institute

Breast cancer spreading to other organs usually heralds a poorer prognosis. Researchers at the University and University Hospital of Basel have discovered a process that helps breast cancer cells implant themselves in certain places in the body. The results suggest a way of preventing secondary tumors.

For eight years, a team led by Professor Mohamed Bentires-Alj worked to establish the role of a cellular enzyme in breast cancer metastasis. The three lead authors Joana Pinto Couto, Milica Vulin, Charly Jehanno and collaborators discovered a mechanism that appears to support metastasis in a range of aggressive cancers. The team has reported their findings in the Embo Journal.

A cell can be pictured like a social network: in theory, every person is connected to every other person in the world through surprisingly few degrees of separation. Cell factors in molecular networks are connected to each other in an analogous way. If one stops functioning correctly, the system is thrown out of balance. The result is a cascade of effects that can have wide-ranging and unexpected consequences on more distant parts of the network. Deciphering these cascades can contribute to our understanding of how a minor defect in a cell’s system can lead to diseases like cancer. These insights offer ideas for new treatments.

Progesterone could protect against Parkinson's

Lennart Stegemann (left) and Paula Neufeld are working on their doctoral theses and were able to celebrate an early success with the top-class publication.
Photo Credit: © RUB, Marquard

In one study, progesterone showed a protective effect on the nerve cells of the intestine. This gives hope for the hormone to be used against Parkinson's.

There is mutual communication between the nerve cells of the gastrointestinal tract and those in the brain and spinal cord. It suggests that the digestive nervous system could affect brain processes that lead to Parkinson's. Paula Neufeld and Lennart Stegemann, who are doing their doctorate in the cytology department of the Medical Faculty of the Ruhr University Bochum, have demonstrated progesterone receptors for the first time in the nerve cells of the gastrointestinal tract and have shown that progesterone protects the cells. Their discovery opens up perspectives for the development of novel neuroprotective therapeutic approaches to counteract diseases such as Parkinson's or Alzheimer's. The study is in the journal Cells.

Research reveals ants inflict pain with neurotoxins

Bullet ants, along with Australian green ants, inflict pain by targeting nerve cells.
Photo Credit: Hadrien Lalagüe.

University of Queensland researchers have shown for the first time that some of the world’s most painful ant stings target nerves, like snake and scorpion venom.

Dr Sam Robinson and colleagues at UQ’s Institute for Molecular Bioscience discovered the ant neurotoxins while studying the Australian green ant and South American bullet ant which have stings that cause long-lasting pain.

“We have shown that these ant venoms target our nerve cells that send pain signals,” Dr Robinson said.

“Normally, the sodium channels in these sensory neurons open only briefly in response to a stimulus.

“We discovered that the ant toxins bind to the sodium channels and cause them to open more easily and stay open and active, which translates to a long-lasting pain signal.

Physicists discover an exotic material made of bosons

 Two stacked lattices with one slightly offset create a new pattern called a moiré
Photo Credit Matt Perko

Take a lattice — a flat section of a grid of uniform cells, like a window screen or a honeycomb — and lay another, similar lattice above it. But instead of trying to line up the edges or the cells of both lattices, give the top grid a twist so that you can see portions of the lower one through it. This new, third pattern is a moiré, and it’s between this type of overlapping arrangement of lattices of tungsten diselenide and tungsten disulfide where UC Santa Barbara physicists found some interesting material behaviors.

“We discovered a new state of matter — a bosonic correlated insulator,” said Richen Xiong, a graduate student researcher in the group of UCSB condensed matter physicist Chenhao Jin, and the lead author of a paper in the journal Science. According to Xiong, Jin and collaborators from UCSB, Arizona State University and the National Institute for Materials Science in Japan, this is the first time such a material      has been created in a “real” (as opposed to synthetic) matter system. The unique material is a highly ordered crystal of bosonic particles called excitons.

“Conventionally, people have spent most of their efforts to understand what happens when you put many fermions together,” Jin said. “The main thrust of our work is that we basically made a new material out of interacting bosons.”

Imaging agents light up two cancer biomarkers at once to give more complete picture of tumor

Researcher Indrajit Srivastava holds solutions of nanoparticles that can target two cancer biomarkers, giving off two distinct signals when lit by one fluorescent wavelength.  This could give surgeons a more complete picture of a tumor and guide operating-room decisions. In the background is a microscopic scan of a tissue sample. 
Photo Credit: Fred Zwicky

Cancer surgeons may soon have a more complete view of tumors during surgery thanks to new imaging agents that can illuminate multiple biomarkers at once, University of Illinois Urbana-Champaign researchers report. The fluorescent nanoparticles, wrapped in the membranes of red blood cells, target tumors better than current clinically approved dyes and can emit two distinct signals in response to just one beam of surgical light, a feature that could help doctors distinguish tumor borders and identify metastatic cancers. 

The imaging agents can be combined with bioinspired cameras, which the researchers previously developed for real-time diagnosis during surgery, said research group leader Viktor Gruev, an Illinois professor of electrical and computer engineering. In a new study in the journal ACS Nano, the researchers demonstrated their new dual-signal nanoparticles in tumor phantoms – 3D models that mimic the features of tumors and their surroundings – and in live mice. 

“If you want to find all the cancer, imaging one biomarker is not enough. It could miss some tumors. If you introduce a second or a third biomarker, the likelihood of removing all cancer cells increases, and the likelihood of a better outcome for the patients increases.” said Gruev, who also is a professor in the Carle Illinois College of Medicine. “Multiple-targeted drugs and imaging agents are a recent trend, and our group is driving the trend hard because we have the camera technology that can image multiple signals at once.”

Electrical synapses in the neural network of insects found to have unexpected role in controlling flight power

The fruit fly Drosophila melanogaster flaps its wings two hundred times per second to fly forwards.
 Photo Credit: Silvan Hürke

Researchers of Mainz University and Humboldt-Universität zu Berlin revealed previously unknown function of electrical synapses, thus deciphering the neural circuit used to regulate insect wingbeat frequency

A team of experimental neurobiologists at Johannes Gutenberg University Mainz (JGU) and theoretical biologists at Humboldt-Universität zu Berlin has managed to solve a mystery that has been baffling scientists for decades. They have been able to determine the nature of the electrical activity in the nervous system of insects that controls their flight. In a paper recently published in Nature, they report on a previously unknown function of electrical synapses employed by fruit flies during flight.

The fruit fly Drosophila melanogaster beats its wings around 200 times per second in order to move forward. Other small insects manage even 1,000 wingbeats per second. It is this high frequency of wingbeats that generates the annoying high-pitched buzzing sound we commonly associate with mosquitoes. Every insect has to beat its wings at a certain frequency to not get “stuck” in the air, which acts as a viscous medium due to their small body size. For this purpose, they employ a clever strategy that is widely used in the insect world. This involves reciprocal stretch activation of the antagonistic muscles that raise and depress the wings. The system can oscillate at high frequencies, thus producing the high rate of wingbeats required for propulsion. The motor neurons are unable to keep pace with the speed of the wings so that each neuron generates an electrical pulse that controls the wing muscles only about every 20th wingbeat. These pulses are precisely coordinated with the activity of other neurons. Special activity patterns are generated in the motor neurons that regulate the wingbeat frequency. Each neuron fires at a regular rate but not at the same time as the other neurons. There are fixed intervals between which each of them fires. While it has been known since the 1970s that neural activity patterns of this kind occur in the fruit fly, there was no explanation of the underlying controlling mechanism.

Testing for 'zombie cells' could boost number of hearts for transplant

Image Credit: PublicDomainPictures

Scientific Frontline: Extended "At a Glance" Summary: Senescent "Zombie" Cells in Heart Transplants

The Core Concept: Senescent cells, commonly referred to as "zombie" cells, are living but dysfunctional cells that release harmful molecules capable of inducing senescence in neighboring cells, triggering inflammation, and forming scar tissue within the heart muscle.

Key Distinction/Mechanism: Rather than relying exclusively on chronological age to determine organ viability, clinicians can identify the biological signature of senescent cells. These cells secrete elevated levels of specific proteins, such as GDF15, and possess distinct RNA markers like p21, which serve as quantifiable indicators of a heart's true biological age and functional health.

Origin/History: The foundational research identifying this senescent signature was presented in June 2023 at the British Cardiovascular Society conference by scientists from Newcastle University, supported by funding from the British Heart Foundation and the Medical Research Council.

Fungi stores a third of carbon from fossil fuel emissions and could be essential to reaching net zero

The fungi make up a vast underground network all over the planet underneath grasslands and forests, as well as roads, gardens, and houses on every continent on Earth
Photo Credit: Florian van Duyn

Researchers are now calling for fungi to be considered more heavily in conservation and biodiversity policies, and are investigating whether we can increase how much carbon the soil underneath us can hold

The vast underground network of fungi beneath our feet stores over 13 gigatons of carbon around the world, roughly equivalent to 36 per cent of yearly global fossil fuel emissions, according to new research.

It is widely believed that mycorrhizal fungi could store carbon, as the fungi forms symbiotic relationships with almost all land plants and transports carbon, converted into sugars and fats by the plant, into soil, but until now the true extent of just how much carbon the fungi were storing wasn’t known.

The discovery by a team of scientists, including researchers from the University of Sheffield, that fungi is storing over a third of the carbon created from fossil fuel emissions each year indicates that it could be crucial as nations seek to tackle climate change and reach net zero. Work is now being undertaken to see whether we could increase how much carbon the soil underneath us can store.

New findings about human metabolic processes

Using genome-wide analysis, the researchers identified 1,299 genetic alterations that impact on metabolites in blood plasma and urine. Shown here are the 282 gene locations where enzymes and transporter proteins that influence metabolism are located.
Full Size Image
Image Credit: Anna Köttgen/Universität Freiburg

Researchers at the Faculty of Medicine at the University of Freiburg have gained significant new insights into metabolic processes in the kidney. The scientists from the Institute of Genetic Epidemiology at the Medical Center - University of Freiburg measured tiny molecules, so-called metabolites, which occur in blood and urine and reflect our metabolism, in samples from more than 5,000 study participants. They compared these with the genome of the test persons and were able to identify 1,299 genetic changes that are associated with metabolites and contribute to their production, degradation or transport. The findings provide a better understanding of processes throughout the body and particularly in the kidney, which produces urine from blood plasma. These discoveries, which appeared June 5, 2023, in the journal Nature Genetics, could lead to a better understanding of diseases and new approaches to their treatment. For example, a new class of therapies for treating diabetes, called SGLT2 inhibitors, work by inhibiting a metabolite transporter in the kidney.

Delirium risk in the Emergency Department for older adults

Katren Tyler led team of researchers that discovered detrimental effects of prolonged ED stays on older patients' health.
Photo Credit: Courtesy of University of California, Davis Health

New UC Davis Health research reveals a significant association between the length of stay in the emergency department (ED) and the development of incident delirium in older adults.

The study, published this month in the Western Journal of Emergency Medicine, was conducted by a team of emergency medicine physicians. It sheds light on the detrimental effects of prolonged ED stays on older patients' health.

Katren Tyler, vice chair for geriatric emergency medicine and wellness and senior author of the study, commented, "Prolonged ED length of stay can have detrimental effects on older patients, especially those with a history of dementia and multiple comorbidities. Swift assignment and transfer to inpatient beds for admitted older patients will not only reduce the risk of delirium but also benefit both patients and health systems."

Delirium is a sudden change in mental function that can include confusion, rapid mood changes and is often reversible.  It is a common and costly condition among older adults, often goes unrecognized and can have severe consequences. The estimated costs associated with delirium to the health care system fall between $38 billion and $152 billion annually.   

Computational model mimics humans’ ability to predict emotions

While a great deal of research has gone into training computer models to infer someone’s emotional state based on their facial expression, that is not the most important aspect of human emotional intelligence, says MIT Professor Rebecca Saxe. Much more important is the ability to predict someone’s emotional response to events before they occur.
Image Credit: Christine Daniloff, MIT
(CC BY-NC-ND 3.0)

When interacting with another person, you likely spend part of your time trying to anticipate how they will feel about what you’re saying or doing. This task requires a cognitive skill called theory of mind, which helps us to infer other people’s beliefs, desires, intentions, and emotions.

MIT neuroscientists have now designed a computational model that can predict other people’s emotions — including joy, gratitude, confusion, regret, and embarrassment — approximating human observers’ social intelligence. The model was designed to predict the emotions of people involved in a situation based on the prisoner’s dilemma, a classic game theory scenario in which two people must decide whether to cooperate with their partner or betray them. 

To build the model, the researchers incorporated several factors that have been hypothesized to influence people’s emotional reactions, including that person’s desires, their expectations in a particular situation, and whether anyone was watching their actions.

“These are very common, basic intuitions, and what we said is, we can take that very basic grammar and make a model that will learn to predict emotions from those features,” says Rebecca Saxe, the John W. Jarve Professor of Brain and Cognitive Sciences, a member of MIT’s McGovern Institute for Brain Research, and the senior author of the study.

PSI researchers use extreme UV light to produce tiny structures for information technology.

The PSI researchers involved at the XIL-II beamline of the SLS. From left to right: Yasin Ekinci, Gabriel Aeppli, Matthias Muntwiler, Procopios Christou Constantinou, Dimitrios Kazazis, Prajith Karadan
Photo Credit: Paul Scherrer Institute/Mahir Dzambegovic

Researchers at PSI have refined a process known as photolithography, which can further advance miniaturization in information technology.

In many areas of information technology, the trend towards ever more compact microchips continues unabated. This is mainly because production processes make it possible to achieve ever smaller structures, so that the same number of information-processing components takes up less and less space. Fitting more components into less space increases the performance and lowers the price of the microchips used in smartphones, smartwatches, game consoles, televisions, Internet servers and industrial applications.

A research group led by Dimitrios Kazazis and Yasin Ekinci at the Laboratory for X-ray Nanoscience and Technologies at the Paul Scherrer Institute PSI, in collaboration with researchers from University College London (UCL) in the UK, has now succeeded in making important progress towards further miniaturization in the IT industry. The scientists have demonstrated that photolithography – the method of patterning widely used in the mass production of microchips – works even when no photosensitive layer has been applied to the silicon.

How Studying Poop May Help Us Boost White Rhino Populations

White Rhinoceros with baby, being protected from poachers. Shot in the Kruger National Park, South Africa.
Photo Credit: Nadine Venter

Researchers at North Carolina State University have identified significant differences in the gut microbiome of female southern white rhinos who are reproducing successfully in captivity, as compared to females who have not reproduced successfully in captivity. The work raises questions about the role that a particular genus of gut microbes may be playing in limiting captive breeding of this rhinoceros species.

“Our work focuses on the southern white rhinoceros (Ceratotherium simum simum), because while it is not yet endangered, species numbers are declining in the wild due to poaching,” says Christina Burnham, first author of a paper on the work and a former graduate student at NC State.

“There is a significant population of southern white rhinos under human care in the United States, but there have been challenges in getting many of these animals to reproduce successfully. It is critical we understand why, as the managed rhinos serve as important assurance populations in case wild rhino numbers continue to fall. We wanted to know how the gut microbiome may influence the reproductive ability of these rhinos.”

Women more likely to experience repeat Toxoplasmosis

Ocular syphilis on the rise
Video Credit: Flinders University

Women are more likely to experience recurrent cases of the Toxoplasma parasite, according to new Flinders University research.

With the condition putting people at risk of further attacks of toxoplasmosis that can progressively damage the retina and lead to vision loss, international experts have demonstrated that women are also more likely to have more than one lesion in their eyes.

The new study, which analyzed the impact of toxoplasmosis on 262 participants at an eye clinic in Brazil, aims to address differences in the way dangerous infections like toxoplasmosis impact people because of their gender to develop targeted treatments.

Closely associated with cats, Toxoplasma is a parasite that causes the infectious disease known as toxoplasmosis. For humans, while domestic cat feces can be a carrier, the most common route of infection is by eating undercooked or raw meat sourced from infected livestock.