Detector Advance Could Lead to Cheaper, Easier Medical Scans

PET scanners such as this EXPLORER scanner at UC Davis are useful tools in medical diagnosis. New work by biomedical engineers at UC Davis and Hamamatsu Photonics, Japan, could lead to cheaper, easier medical imaging. (Photo by UC Davis Health)

Researchers in the U.S. and Japan have demonstrated the first experimental cross-sectional medical image that doesn’t require tomography, a mathematical process used to reconstruct images in CT and PET scans . The work, published in Nature Photonics, could lead to cheaper, easier and more accurate medical imaging.

The advance was made possible by development of new, ultrafast photon detectors, said Simon Cherry, professor of biomedical engineering and of radiology at the University of California, Davis, and senior author on the paper.

“We’re literally imaging at the speed of light, which is something of a holy grail in our field,” Cherry said.

Experimental work was led by Sun Il Kwon, project scientist in the UC Davis Department of Biomedical Engineering and Ryosuke Ota at Hamamatsu Photonics, Japan, where the new photon detector technology was developed. Other collaborators included research groups led by Professor Yoichi Tamagawa at the University of Fukui, and by Professor Tomoyuki Hasegawa at Kitasato University.

Research unlocks the technology to produce unbreakable screens

Luminating composite glasses

Cracked phone screens could become a thing of the past thanks to breakthrough research conducted at The University of Queensland.

The global team of researchers, led by UQ’s Dr Jingwei Hou, Professor Lianzhou Wang and Professor Vicki Chen, have unlocked the technology to produce next-generation composite glass for lighting LEDs and smartphone, television and computer screens.

The findings will enable the manufacture of glass screens that are not only unbreakable but also deliver crystal clear image quality.

Dr Hou said the discovery was a huge step forward in perovskite nanocrystal technology as previously, researchers were only able to produce this technology in the bone-dry atmosphere of a laboratory setting.

“The emitting materials are made from nanocrystals, called lead-halide perovskites,” he said.

“They can harvest sunlight and concert it into renewable electricity - playing a vital role in low-cost and high-efficiency new generation solar cells and many promising applications like lighting.

“Unfortunately, these nanocrystals are extremely sensitive to light, heat, air and water – even water vapor in our air would kill the current devices in a matter of minutes.

“Our team of chemical engineers and material scientists has developed a process to wrap or bind the nanocrystals in porous glass.

New results deal a blow to the theoretical sterile neutrino

Teams prepare to move the MicroBooNE cryostat from DZero to the Liquid Argon Test Facility (LArTF).  Credit: Cindy Arnold, Fermilab

The results were gathered by an international team at the MicroBooNE experiment in the United States, with leadership from a UK team including researchers from the University of Cambridge.

The two most likely explanations for anomalies that were seen in two previous physics experiments: one which suggests a sterile neutrino, and one which points at limitations in those experiments, have been ruled out by MicroBooNE.

The fourth neutrino

For more than two decades, this proposed fourth neutrino has remained a promising explanation for anomalies seen in earlier physics experiments. In these previous experiments, neutrinos were observed acting in a way not explained by the Standard Model of Physics – the leading theory to explain the building blocks of the universe and everything in it.

Neutrinos are the most abundant particle with mass in our universe, but they rarely interact with other matter, making them hard to study. But these elusive particles seem to hold answers to some of the biggest questions in physics – such as why the universe is made up of more matter than antimatter.

A 170-ton neutrino detector the size of a bus was created to study these particles – and became known as MicroBooNE. The international experiment has close to 200 collaborators from 36 institutions in five countries, and is supported by the Science and Technology Facilities Council (STFC) in the UK.

Climate change increases fluvial sediment in the high mountains of Asia

The Laigu Glacier in southeastern High Mountain Asia. (Photo credit: Dongfeng Li)

The findings have far reaching implications for the region’s hydropower, food and environmental security

High Mountain Asia (HMA), which refers to the Tibetan Plateau and the surrounding high Asian mountains, is home to the world’s third-largest ice reservoir and the origin of many of Asia’s large rivers. In fact, these rivers are crucial lifelines for a third of the world’s population. The rivers in HMA are experiencing increased runoff and sediment fluxes from amplified climate change, glacier melt and permafrost thaw.

To examine the impact of these phenomena on HMA, Professor Lu Xixi and Dr. Dongfeng Li from the Department of Geography at the National University of Singapore (NUS) Faculty of Arts and Social Sciences led an international team of researchers to conduct a new analysis of observations of headwater rivers in the area. The study revealed that fluvial sediment loads have been increasing substantially, even much faster than river water discharge. This is due to the recent warmer and wetter climate, and has important implications for water quality, hydropower development and maintenance, and for the riverine carbon cycle.

Dr Li, Research Fellow from the NUS Department of Geography and the study’s lead author, said “Climate change is accelerating glacier retreat and permafrost thaw, resulting in the previously frozen landscapes becoming more erodible. Our study shows that emerging process, such as glacier retreat and permafrost thaw, will enhance the transport of sediments from slopes to river systems, especially when regional extreme rainstorms are also increasing. This has significant knock-on effects on the region’s hydropower, food and environmental security, potentially affecting millions of people in HMA and downstream regions.”

Study finds the SARS-CoV-2 virus can infect the inner ear

Many Covid-19 patients have reported symptoms affecting the ears, including hearing loss and tinnitus. Dizziness and balance problems can also occur, suggesting that the SARS-CoV-2 virus may be able to infect the inner ear.

A new study from MIT and Massachusetts Eye and Ear provides evidence that the virus can indeed infect cells of the inner ear, including hair cells, which are critical for both hearing and balance. The researchers also found that the pattern of infection seen in human inner ear tissue is consistent with the symptoms seen in a study of 10 Covid-19 patients who reported a variety of ear-related symptoms.

The researchers used novel cellular models of the human inner ear that they developed, as well as hard-to-obtain adult human inner ear tissue, for their studies. The limited availability of such tissue has hindered previous studies of Covid-19 and other viruses that can cause hearing loss.

“Having the models is the first step, and this work opens a path now for working with not only SARS-CoV-2 but also other viruses that affect hearing,” says Lee Gehrke, the Hermann L.F. von Helmholtz Professor in MIT’s Institute for Medical Engineering and Science, who co-led the study.

Konstantina Stankovic, a former associate professor at Harvard Medical School and former chief of otology and neurotology at Massachusetts Eye and Ear, who is now the Bertarelli Foundation Professor and chair of the Department of Otolaryngology – Head and Neck Surgery at Stanford University School of Medicine, co-led the study. Minjin Jeong, a former postdoc in Stankovic’s laboratory at Harvard Medical School, who is now at Stanford Medical School, is the lead author of the paper, which appears today in Communications Medicine.

Researchers set ‘ultrabroadband’ record with entangled photons

Researchers in the lab of Qiang Lin at the University of Rochester have generated record ‘ultrabroadband’ bandwidth of entangled photons using the thin-film nanophotonic device illustrated here. At top left, a laser beam enters a periodically poled thin-film lithium niobate waveguide (banded green and gray). Entangled photons (purple and red dots) are generated with a bandwidth exceeding 800 nanometers.
(Illustration by Usman Javi and Michael Osadciw)

The engineers have achieved unprecedented bandwidth and brightness on chip-sized nanophotonic devices.

Quantum entanglement—or what Albert Einstein once referred to as “spooky action at a distance”— occurs when two quantum particles are connected to each other, even when millions of miles apart. Any observation of one particle affects the other as if they were communicating with each other. When this entanglement involves photons, interesting possibilities emerge, including entangling the photons’ frequencies, the bandwidth of which can be controlled.

Researchers at the University of Rochester have taken advantage of this phenomenon to generate an incredibly large bandwidth by using a thin-film nanophotonic device they describe in Physical Review Letters.

The breakthrough could lead to:

1. Enhanced sensitivity and resolution for experiments in metrology and sensing, including spectroscopy, nonlinear microscopy, and quantum optical coherence tomography
2. Higher dimensional encoding of information in quantum networks for information processing and communications

“This work represents a major leap forward in producing ultrabroadband quantum entanglement on a nanophotonic chip,” says Qiang Lin, professor of electrical and computer engineering. “And it demonstrates the power of nanotechnology for developing future quantum devices for communication, computing, and sensing,”

Heatwaves like ‘the Blob’ could decrease role of ocean as carbon sink

A major two-year heatwave may have temporarily dampened the Pacific’s ability to sequester carbon, according to research from the University of British Columbia and University of Southern Denmark. Credit: Jody Wright

Researchers have found the two-year heatwave known as ‘the Blob’ may have temporarily dampened the Pacific’s ‘biological pump,’ which shuttles carbon from the surface ocean to the deep sea where it can be stored for millennia.

Canadian and European researchers, in collaboration with the U.S. Department of Energy Joint Genome Institute, conducted a large-scale study of the impact of one of the largest marine heatwaves on record – colloquially known as the Blob – on Pacific Ocean microorganisms. Their observations suggest that it’s not just larger marine life that is affected by abrupt changes in sea temperature.

“Heatwaves such as the Blob may decrease the ocean’s biological role as a carbon sink for fixed atmospheric carbon,” said Dr. Steven Hallam (he/him), a microbiologist at the University of British Columbia and author of the paper published in Nature Communications Biology.

This ‘biological pump’ process is an important mechanism for buffering the impact of human activity on Earth’s climate, said co-author Dr. Colleen Kellogg (she/her), a research scientist with the Hakai Institute. “The ocean is a huge global reservoir for atmospheric carbon dioxide. If marine heatwaves reduce the capacity for carbon dioxide to be absorbed into the ocean, then this shrinks this reservoir and leaves more of this greenhouse gas in the atmosphere.”

Ways to make equestrian sport safer for horses and riders

Photo by Jean van der Meulen from Pexels

In the first study of horse falls for over 20 years, University of Bristol academics have identified some simple interventions to reduce the risk of injury in equestrian sport - making it safer for both horses and riders.

The study pinpointed characteristics associated with an increased risk of falls in eventing, such as higher-level events, longer courses, more starters at cross-country phase and less experienced horses and athletes.

Identifying these risk factors allows riders and event organizers to assess the level of risk for individual horse, rider and event combinations. The study, published in the Equine Veterinary Journal, recommends simple mitigations such as adjusting minimum eligibility requirements (MERs) to ensure horses and riders always compete at a level appropriate to their ability.

Led by Bristol Veterinary School’s Dr. Euan Bennet and Professor Tim Parkin, with Dr Heather Cameron-Whytock of Nottingham Trent University, and funded by Federation Equestre Internationale (FEI), it is the first large scale study using a global data set of every FEI eventing competition over an 11-year period.

Engineering molecules to turn off inflammation

Stylized scientific image of the anti-inflammatory
molecule, Interleukin-37

In a long-term collaboration between researchers and industry, an exciting first step has been made in the creation of a new generation of medicines for auto-immune diseases such as arthritis and inflammatory bowel disease using one of our body’s own anti-inflammatory off-switch molecules.

Our body’s own immune system produces many highly potent anti-inflammatory molecules, but they are often highly fragile, short-lived, and do not have drug-like properties. Interleukin-37 is one such molecule produced by the body to turn off inflammation.

Together with partner F. Hoffmann-La Roche (Roche), the multidisciplinary research team from the Monash University Biomedicine Discovery (BDI) Institute, Monash University’s Department of Pediatrics and the Hudson Institute of Medical Research have harnessed their Fc-fusion platform to engineer the next generation of Interleukin-37, one that retains anti-inflammatory potency, is highly stable and has an excellent therapeutic likeness.

The findings from the research collaboration have now been published in Cell Chemical Biology.

A little bit of inflammation can be a good thing and is often the body's immune system doing its job. However, when inflammation persists, or the immune system starts attacking the body’s own cells, this can lead to disease.

One of the study’s lead authors Dr. Andrew Ellisdon from the Monash BDI says many human diseases, including autoimmune diseases such as arthritis or inflammatory bowel disease, are characterized by too much inflammation. There is a gap in producing new generations of potent anti-inflammatory therapeutics.

Urgent changes needed to global guidelines designed to stop surgical infection

Wound infections are the most common problem after surgery, particularly in developing countries, but promised innovations to tackle the issue do not work and global guidance needs changing, a new study reveals.

Both World Health Organization (WHO) and the UK’s National Institute of Health Research guidelines recommend that surgeons use alcoholic chlorhexidine skin preparation and triclosan coated sutures to prevent Surgical Site Infection (SSI).

However, the world’s largest wound infection trial could not demonstrate superiority of these interventions over lower cost alternatives.

Carried out in Benin, Ghana, India, Mexico, Nigeria, Rwanda and South Africa, the FALCON trial was funded by the UK’s National Institute for Health Research (NIHR).

Publishing their findings today in The Lancet, researchers participating in this study are calling for guidelines recommending these measures, either specifically to Low- and Middle-income Countries (LMIC) or at a general global level, to be revised.

Co-author Mr. Aneel Bhangu, from the University of Birmingham, commented: “Surgical site infection is the world’s most common postoperative complication - a major burden for both patients and health systems. We have delivered the biggest trial of its kind, where we could not demonstrate the superiority of these interventions over cheaper alternatives.