. Scientific Frontline

Tuesday, September 13, 2022

Insects struggle to adjust to extreme temperatures making them vulnerable to climate change

Cardinal beetle 
Credit: Erik Karits from Pixabay

Insects have weak ability to adjust their thermal limits to high temperatures and are thus more susceptible to global warming than previously thought.

As more frequent and intense heat waves expose animals to temperatures outside of their normal limits, an international team led by researchers at the University of Bristol studied over 100 species of insect to better understand how these changes will likely affect them.

Insects – which are as important as pollinators, crop pests and disease vectors - are particularly vulnerable to extreme temperatures. One-way insects can deal with such extremes is through acclimation, where previous thermal exposure extends their critical thermal limits. Acclimation can trigger physiological changes such as the upregulation of heat shock proteins, and result in changes to phospholipid composition in the cell membrane.

The team discovered that insects struggle to do this effectively, revealing acclimation of both upper and lower critical thermal limits was weak – for each 1°C shift in exposure, limits were adjusted by only 0.092°C and 0.147°C respectively (i.e. only a small compensation of 10 or 15%).

Little Ice Age study reveals North Atlantic reached a tipping point

Ocean quahog clam.
Credit Paul Kay

Scientists have used centuries-old clam shells to see how the North Atlantic climate system reached a "tipping point" before the Little Ice Age.

The Little Ice Age – a period of regional cooling, especially in the North Atlantic – lasted several centuries, ending in about 1850.

A long-standing theory suggests initial cooling in this period was sustained by "sea-ice to ocean feedbacks" – sea ice expanded and this slowed ocean currents which in turn reduced the flow of warm water from the south.

The new study, by the University of Exeter, used the shells of quahog clams – which can live for several hundred years – to understand how the ocean has evolved and responded to external changes over recent centuries.

The findings show that the North Atlantic climate system destabilized and lost resilience (the ability to recover from external changes) prior to the Little Ice Age, possibly causing it to "tip" into a new, colder state.

And the researchers say the North Atlantic could be approaching a new tipping point, with major consequences for the region's climate.

Optical rule was made to be broken

A scanning electron microscope image of an iron pyrite metasurface created at Rice University to test its ability to transcend the Moss rule, which describes a trade-off between a material’s optical absorption and how it refracts light. The research shows potential to improve screens for virtual reality and 3D displays along with optical technologies in general.
Credit: The Naik Lab/Rice University

If you’re going to break a rule with style, make sure everybody sees it. That’s the goal of engineers at Rice University who hope to improve screens for virtual reality, 3D displays and optical technologies in general.

Gururaj Naik, an associate professor of electrical and computer engineering at Rice’s George R. Brown School of Engineering, and Applied Physics Graduate Program alumna Chloe Doiron found a way to manipulate light at the nanoscale that breaks the Moss rule, which describes a trade-off between a material’s optical absorption and how it refracts light.

Apparently, it’s more like a guideline than an actual rule, because a number of “super-Mossian” semiconductors do exist. Fool’s gold, aka iron pyrite, is one of them.

For their study in Advanced Optical Materials, Naik, Doiron and co-author Jacob Khurgin, a professor of electrical and computer engineering at Johns Hopkins University, find iron pyrite works particularly well as a nanophotonic material and could lead to better and thinner displays for wearable devices.

More important is that they’ve established a method for finding materials that surpass the Moss rule and offer useful light-handling properties for displays and sensing applications.

Study finds white children more likely to be overdiagnosed for ADHD

A new study by Professor Paul Morgan finds that white children are more likely to be overdiagnosed for ADHD than children of color.
Photo credit: Ben White on Unsplash

A new study led by Paul Morgan, Harry and Marion Eberly Faculty Fellow and professor of education (educational theory and policy) and demography, and published in the Journal of Learning Disabilities, examines which sociodemographic groups of children are more likely to be overdiagnosed and overtreated for ADHD. The researchers analyzed data from 1,070 U.S. elementary school children who had previously displayed above-average behavioral, academic or executive functioning the year before their initial ADHD diagnoses. The team said those children were considered unlikely to have ADHD by the researchers because children diagnosed and treated for ADHD should displaychronically inattentive, hyperactive or impulsive behaviors that impair their functioning and result in below-average academic or social development.

A problem with ADHD overdiagnosis, Morgan said, is that it contributes to stigma and skepticism toward those experiencing more serious impairments.

“It undermines a confidence in the disorder,” he said. “If anyone can be diagnosed with ADHD, then what is ADHD? For those who have significant impairments, they may experience greater skepticism about the condition. Mental health resources are already scarce, those with serious impairments could lose out.”

Live Intracellular Imaging with New, Conditionally Active Immunofluorescence Probe

Figure 1
Schematic (a) and mechanism (c) of p53 Intra Q-body. (b) p53-dependent fluorescence signal and (d) microscopy images. (a) The double labelled fluorescent dye in the antigen fragment-based Q-body is de-quenched on binding with the target antigen, thus displaying fluorescent signaling for visualizing the intracellular target. (b) p53 peptide concentration-dependent variation in fluorescence signal intensity. (c) Q-body displays a high fluorescent signal on binding with the target in cells expressing p53, as compared to the 'p53' negative human cells. (d) Confocal microscopy images of HCT116 p53 and SK-BR-3. Cells which do not express p53, i.e., HCT116 p53(-/-) exhibit no TAMRA-based fluorescence while others (including images stained with Hoechst dye for illuminating nucleus and under bright-field to show the cells) display significant fluorescence.
Source/Credit: Tokyo Institute of Technology

Furthering the visualization of intracellular dynamics for therapeutic applications, a Tokyo Tech research team has now demonstrated precise imaging of endogenous proteins in live cells using an antigen-binding fragment (Fab)-based Quenchbody (Q-body). The Q-body probe shows antigen-dependent response and a switchable (on-off) fluorescent signaling, enabling the visualization and sorting of cells expressing p53, a tumor suppressor biomarker protein.

Recent advances in imaging technology have made it possible to visualize intracellular dynamics, which offers a better understanding of several key biological principles for accelerating therapeutic development. Fluorescent labeling is one such technique that is used to identify intracellular proteins, their dynamics, and dysfunction. Both internal as well as external probes with fluorescent dyes are used for this purpose, although external probes can better visualize intracellular proteins as compared to the internal probes. However, their application is limited by non-specific binding to intracellular components, resulting in a low target specific signaling and higher background noise.

Simulation helps in the search for the origin of cosmic radiation

The colorful lines show how cosmic radiation is deflected in magnetic fields. The white straight lines represent a large-scale magnetic field. In addition, small-scale magnetic fields not shown here act on the orbits of the particles (colorful lines).
Credit: RUB, Dr. Lukas Merten

The cosmic radiation seems to be all around us. That is exactly what makes it difficult to find their sources. It would be helpful if you could trace your way back through space. A new program helps with this.

An international research team has developed a computer program that can be used to simulate the transport of cosmic radiation through space. The scientists hope to be able to solve the puzzle about the sources of cosmic radiation. So far it is unknown which celestial objects emit the high-energy radiation that patterns the earth from space. In order to be able to explain experimental data, theoretical models are required; the new computer simulation can deliver this. A team of researchers from the Ruhr University Bochum (RUB) describes the software in the journal of Cosmology and Astroparticle Physics, published online on September 12, 2022.

Like a uniformly illuminated sky during the day

Since their discovery of 100 years, researchers have been trying to decipher where the cosmic radiation comes from. The problem: viewed from Earth, it looks like heaven by day with the naked eye: it is illuminated almost everywhere where you look. Because the light of the sun is scattered in the earth's atmosphere and is distributed evenly over the entire sky. Cosmic radiation is also scattered on its way to earth - through interactions with cosmic magnetic fields. Only a uniformly illuminated picture can be seen from the earth; the origin of the radiation remains hidden.

Ural Scientists Develop Technology to Correct Genetic Defects

According to Mikhail Bolkov, a regulatory framework is also needed for genetic intervention therapy. Photo credit: Ilya Safarov

Scientists at the Institute of Immunology and Physiology of the Ural Branch of the Russian Academy of Sciences and UrFU develop methods for genetic diagnosis and therapy of diseases caused by primary immunodeficiency. This is a congenital malfunction of one or more parts of the immune system that predisposes to the development of frequent, prolonged, hard-to-treat diseases, not only infectious but also autoimmune, autoinflammatory and oncological diseases. For example, systemic lupus erythematosus, various vasculitis, chronic pneumonia, and even hair loss.

Today, primary immunodeficiencies are treated with replacement therapy and hematopoietic stem cell transplantation. However, the treatment of such diseases promises to become more effective by replacing genetic defects in human DNA. Mikhail Bolkov, a Senior Researcher at the Department of Immunochemistry of Ural Federal University and the Institute of Immunology and Physiology of the Ural Branch of the Russian Academy of Sciences, spoke about this on the air of Radio "Komsomolskaya Pravda".

Monday, September 12, 2022

Slowing of continental plate movement, controlled timing of Earth’s largest volcanic events

Fagradalsfjal volcanic eruption in Iceland.
Photo credit: Tanya Grypachevskaya on Unsplash

Scientists have shed new light on the timing and likely cause of major volcanic events that occurred millions of years ago and caused such climatic and biological upheaval that they drove some of the most devastating extinction events in Earth’s history.

Surprisingly the new research, published today in leading international journal Science Advances, suggests a slowing of continental plate movement was the critical event that enabled magma to rise to the Earth’s surface and deliver the devastating knock-on impacts.

Earth’s history has been marked by major volcanic events, called Large Igneous Provinces (LIPs) – the largest of which have caused major increases in atmospheric carbon emissions that warmed Earth’s climate, drove unprecedented changes to ecosystems, and resulted in mass extinctions on land and in the oceans.

Using chemical data from ancient mudstone deposits obtained from a 1.5 km-deep borehole in Wales, an international team led by scientists from Trinity College Dublin’s School of Natural Sciences was able to link two key events from around 183 million years ago (the Toarcian period).

First JWST images of Orion Nebula released

The inner region of the Orion Nebula as seen by the James Webb Space Telescope’s NIRCam instrument.
Image credit: NASA, ESA, CSA, Data reduction and analysis: PDRs4All ERS Team; graphical processing S. Fuenmayor

An international research team including University of Michigan researchers has just revealed the first images of the Orion Nebula, the richest and closest star nursery in the solar system, captured by the James Webb Space Telescope.

Located in the constellation of Orion, 1,350 light years from Earth, the Orion Nebula is an area rich in matter where many stars are formed. Its environment is similar to the environment in which our solar system was born more than 4.5 billion years ago. Studying allows researchers to understand the conditions in which our solar system formed.

“Orion Bar is a prototype region for processes that occur throughout our galaxy and the universe as stars continually irradiate nearby material,” said Felipe Alarcon, U-M graduate student and member of the international group. “This amazing picture will be a template image.”

The heart of star nurseries, such as the Orion Nebula, is obscured by large amounts of dust—impossible to observe in visible light with telescopes such as the Hubble Space Telescope. The JWST observes the infrared light of the cosmos, penetrating these layers of dust.

The image reveals many spectacular structures, down to scales of about 40 astronomical units, or about the size of our solar system. These structures include a number of dense filaments of matter, which could launch the birth of a new generation of stars. The image also reveals forming stellar systems. These consist of a central proto-star surrounded by a disc of dust and gas inside which planets form.

Dark Energy Camera Captures Bright, Young Stars Blazing Inside Glowing Nebula

NOIRLab, captures the star-forming nebula NGC 6357, which is located 8000 light-years away in the direction of the constellation Scorpius.
Hi-Res Zoomable Image
Credit: CTIO/NOIRLab/DOE/NSF/AURA  T.A. Rector (University of Alaska Anchorage/NSF’s NOIRLab), J. Miller (Gemini Observatory/NSF’s NOIRLab), M. Zamani & D. de Martin (NSF’s NOIRLab)

The 570-megapixel US Department of Energy-fabricated Dark Energy Camera at NOIRLab’s Cerro Tololo Inter-American Observatory in Chile is one of the most powerful tools in astronomy and astrophysics. To commemorate its first decade of discovery and exploration, NOIRLab has released a stunning image of the Lobster Nebula, a brilliant star-forming region located 8000 light-years from Earth in the direction of the constellation Scorpius. The image was unveiled at a conference highlighting DECam’s breakthrough science results.

The Dark Energy Camera (DECam) mounted on the Víctor M. Blanco 4-meter Telescope at Cerro Tololo Inter-American Observatory in Chile, a Program of NSF’s NOIRLab, is celebrating 10 years as one of the highest-performance, wide-field CCD imagers in the world.

To help commemorate DECam’s first decade of operation, NOIRLab has released a breathtaking image of the star-forming Lobster Nebula (NGC 6357), which is located about 8000 light-years from Earth in the direction of the constellation Scorpius. This image reveals bright, young stars surrounded by billowing clouds of dust and gas.

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