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Comment by Dr. Krishna Kumari Challa on August 14, 2023 at 11:29am

Nanoscale 'tattoos' for individual cells could provide early warnings for health problems

Engineers have developed nanoscale tattoos dots and wires that adhere to live cells in a breakthrough that puts researchers one step closer to tracking the health of individual cells. The new technology allows for the first time the placement of optical elements or electronics on live cells with tattoo-like arrays that stick on cells while flexing and conforming to the cells' wet and fluid outer structure. 

They 're talking about putting something like an electronic tattoo on a living object tens of times smaller than the head of a pin. It's the first step towards attaching sensors and electronics on live cells. The structures were able to stick to soft cells for 16 hours even as the cells moved.

The researchers built the tattoos in the form of arrays with gold, a material known for its ability to prevent signal loss or distortion in electronic wiring. They attached the arrays to cells that make and sustain tissue in the human body, called fibroblasts. The arrays were then treated with molecular glues and transferred onto the cells using an alginate hydrogel film, a gel-like laminate that can be dissolved after the gold adheres to the cell. The molecular glue on the array bonds to a film secreted by the cells called the extracellular matrix.

This work has shown we can attach complex nanopatterns to living cells, while ensuring that the cell doesn't die. It's a very important result that the cells can live and move with the tattoos because there's often a significant incompatibility between living cells and the methods engineers use to fabricate electronics.

The researcher's ability to attach the dots and wires in an array form is also crucial. To use this technology to track bioinformation, researchers must be able to arrange sensors and wiring into specific patterns not unlike how they are arranged in electronic chips.

This is an array with specific spacing, not a haphazard bunch of dots. 

Kam Sang Kwok et al, Toward Single Cell Tattoos: Biotransfer Printing of Lithographic Gold Nanopatterns on Live Cells, Nano Letters (2023). DOI: 10.1021/acs.nanolett.3c01960

Comment by Dr. Krishna Kumari Challa on August 14, 2023 at 10:46am

Skeletal elements preserve differing evolutionary forces

Human skeletal morphology is highly diverse and varies among individuals and populations around the globe. This diversity is the result of a complex interplay of various evolutionary forces over a long period of time. Evolutionary biologists divide these forces into two distinct processes. A neutral process refers to mutations producing new diversity which, however, offers no direct advantages or disadvantages to the affected individuals. This new diversity then increases or decreases randomly via what is known as genetic drift within a population.

This is contrasted with non-neutral processes, for example, when mutations do affect the fitness of an individual. As a result, the affected individuals have a greater or lesser ability to adapt to environmental factors.

To draw detailed conclusions about underlying genetic kinship only skeletal elements that evolved through neutral processes should be used.

Therefore , researchers should focus on the teeth and skull, whose structures are considered to have evolved primarily through neutral processes. Contrary to earlier assumptions, not all features in the teeth and skull reliably reflect the underlying genetic code; some are much more suitable than others.  Small morphological features on the teeth, such as groove patterns in the crowns, the number and size of cusps, the shape of the roots, and the presence or absence of wisdom teeth, proved to be particularly suitable. 

Researchers obtain the best results, almost identical to a conventional genetic relationship analysis, when they include all features of the skull and teeth. This is also expected, as more skeletal features provide a richer knowledge of underlying genetic information.

Genetic analyses are often constrained by poor DNA preservation. This is commonly the case with very old bones or those that have been exposed to a warm climate. Damaging bones for DNA analyses is also often out of the question in the case of fragile material or rare finds, or due to ethical reasons. In such cases, the non-destructive examination of skulls and teeth is a valuable alternative for tracing past population history and hominin phylogeny in archaeological contexts, for example, or for inferring ancestry profiles in forensic cases. This , therefore, has implications for the scientific community and society at large.

Comment by Dr. Krishna Kumari Challa on August 14, 2023 at 8:01am

Carbon dioxide - not water - triggers explosive volcanoes

Geoscientists have long thought that water  along with shallow magma stored in Earth's crust drives volcanoes to erupt. Now, thanks to newly developed research tools , scientists have learned that gaseous carbon dioxide can trigger explosive eruptions. A new model suggests that basaltic volcanoes, typically located on the interior of tectonic plates, are fed by a deep magma within the mantle, stored about 20 to 30 kilometers below Earth's surface. The research, which offers a clearer picture of our planet's deep internal dynamics and composition, with implications for improving volcanic-hazards planning, was published Aug. 7 in the Proceedings of the National Academy of Sciences. 

Comment by Dr. Krishna Kumari Challa on August 14, 2023 at 7:59am

The Heliophysics Big Year

Comment by Dr. Krishna Kumari Challa on August 14, 2023 at 7:41am

Stealth swimmers: the fish that hide behind others to hunt

Comment by Dr. Krishna Kumari Challa on August 14, 2023 at 7:37am

Researchers discover antifungal molecule

Fungal infections are killing thousands of people each year, some with a morbidity rate of nearly 80%. The rise in fungal infections is due, in part, to the successful treatment of other diseases. As people live longer and successfully undergo treatments like chemotherapy and organ transplants, they often live with weakened immune systems. When drugs that treat arthritis and other ailments that also weaken immune systems are added to the mix, a perfect storm is created for potentially deadly fungal infections.

To make matters worse, only a handful of antifungal treatments are available, and even those are becoming less effective as fungi become more resistant. However,  researchers have recently published findings in the Journal of Natural Products indicating that a novel breakthrough treatment may have been discovered.
The molecule they're excited about is called persephacin. This antifungal discovery appears to work on a broad spectrum of infectious fungi, and it is reasonably non-toxic to human cells, which is a huge deal because many current treatments are toxic to the human body.

Fungi are found throughout the botanical world, and plants and fungi often work together. Some of these fungi kill competitors or deter insects from eating the plan. So researchers  hypothesized that if these plant-dwelling fungi, known as endophytes, could help the plants fight off infections by killing the invading fungi, then these molecules might also be able to protect humans and animals from fungal pathogens. As it turns out, they were right.

The researchers  developed a novel way to procure leaf samples using a laser device called the Fast Laser-Enabled Endophyte Trapper, or FLEET. This method helps generate samples in a sterile environment and drastically increases the number of samples that can be acquired.

Using traditional methods, they could process roughly four to six samples per minute. But the FLEET system is capable of aseptically generating between 500-600 tissue specimens in 10 minutes. This allowed them to rapidly screen more samples and enhanced the opportunity for potential drug discoveries. This is one of them. Antifungal resistance keeps evolving, and this could provide a new alternative. That's why this molecule is so exciting.

Lin Du et al, Persephacin Is a Broad-Spectrum Antifungal Aureobasidin Metabolite That Overcomes Intrinsic Resistance in Aspergillus fumigatus, Journal of Natural Products (2023). DOI: 10.1021/acs.jnatprod.3c00382

Comment by Dr. Krishna Kumari Challa on August 12, 2023 at 1:19pm

Muon magnetism dashes physics dreams
The most precise measurement of an elementary particle’s magnetism suggests that the ‘standard model’ of physics could be right after all. A discrepancy between predicted and measured values of the magnetic moment of the muon — a heavier cousin of the electron — was seen as a possible signal of undiscovered subatomic particles. Physicists at the Muon g – 2 experiment at Fermilab have now doubled the precision of the previous best measurement, to an estimated error of just 201 parts per billion. And an alternative theoretical prediction is in agreement with this result, suggesting there might not be any discrepancy to explain.

https://muon-g-2.fnal.gov/result2023.pdf?utm_source=Nature+Briefing...

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Soil is home to more than half of all life About 59% of all species on Earth live in soil, estimate researchers who reviewed global biodiversity data. This would make the ground the planet’s single most biodiverse habitat. The figure doubles an earlier estimate and could be even higher because so little is known about soil, the researchers suggest. It is home to 99% of Enchytraeidae worms, 90% of fungi, 86% of plants and more than 50% of bacteria — but only 3% of mammals live in it.

https://www.pnas.org/doi/10.1073/pnas.2304663120

Comment by Dr. Krishna Kumari Challa on August 12, 2023 at 1:00pm

Chemicals from maize roots influence wheat yield

Maize roots secrete certain chemicals that affect the quality of soil. In some fields, this effect increases yields of wheat planted subsequent to maize in the same soil by more than 4%. This was proven by researchers . While the findings from several field experiments show that these effects are highly variable, in the long term they may yet help to make the cultivation of grains more sustainable, without the need for additional fertilizers or pesticides.

Plants produce an abundance of special chemicals. Some of these are released into the soil and influence its quality. This, in turn, affects the next plant to grow in the soil. So far, little research has taken place on the extent to which the excreted chemicals can be used in agriculture to increase productivity.

Recently, however, researchers from the Institute of Plant Sciences (IPS) at the University of Bern have conducted field experiments in this area. With their findings published in the scientific journal eLife, the researchers demonstrate that specialized metabolitesfrom the roots of the maize plant can bring about an increase in the yields of subsequently planted wheat under agriculturally realistic conditions.

On the basis of earlier studies conducted by researchers at the Institute of Plant Sciences (IPS) at the University of Bern, it was known that so-called benzoxazinoids—natural chemicals which maize plants release through their roots—change the composition of microorganisms in the soil on the roots and therefore influence the growth of the subsequent plants that grow in the soil. The present study investigated whether plant-soil feedbacks of this kind also occur under realistic agricultural conditions.

During a two-year field experiment, two lines of maize were initially grown, only one of which released benzoxazinoids into the soil. Three varieties of winter wheat were then grown on the differently conditioned soils.

On this basis, it was possible to demonstrate that the excretion of benzoxazinoids improves germination and increases tillering, growth and crop yield.

In addition to the increased crop, lower levels of infestation by some pests were also observed. A yield increase of 4% may not sound spectacular, but it is still significant considering how challenging it has become to enhance wheat yields without additional inputs.

Valentin Gfeller et al, Plant secondary metabolite-dependent plant-soil feedbacks can improve crop yield in the field, eLife (2023). DOI: 10.7554/eLife.84988

Comment by Dr. Krishna Kumari Challa on August 12, 2023 at 11:28am

Advice to freeze out risk of thermal attacks

A team of computer security experts have developed a set of recommendations to help defend against "thermal attacks" which can steal personal information.

Thermal attacks use heat-sensitive cameras to read the traces of fingerprints left on surfaces like smartphone screens, computer keyboards and PIN pads.

Hackers can use the relative intensity of heat traces across recently-touched surfaces to reconstruct users' passwords.

Last year experts demonstrated how easily thermal images could be used to crack passwords.

They developed ThermoSecure, a system which used AI to scan heat-trace images and correctly guess passwords in seconds, alerting many to the threat of thermal attacks.

Their research,  presented as a paper at the USENIX Security Symposium conference in Anaheim, California, on Friday 11 August, also includes advice to manufacturers on how their devices could be made more secure. 

The team identified 15 different approaches described in previous papers on computer security which could reduce the risk of thermal attacks.

Those included ways to reduce the transfer of heat from users' hands, by wearing gloves or rubber thimbles, or changing the temperature of hands by touching something cold before typing.

Approaches suggested in the literature also included pressing hands against surfaces or breathing on them to obscure their fingerprint heat once they had finished typing.

Other suggestions for increased security focused on hardware and software. A heating element behind surfaces could erase traces of finger heat, or surfaces could be made from materials which dissipate heat more rapidly.

Security on public surfaces could be increased by introducing a physical shield which covers keys until heat has dissipated. Alternatively, eye-tracking inputs or biometric security could reduce the risk of successful thermal attacks.

The paper concludes with recommendations for users on how they can defend themselves against thermal attacks in public, and for device manufacturers on how safety measures could be built into future generations of hardware and software.

 In the Quest to Protect Users from Side-Channel Attacks—A User-Centred Design Space to Mitigate Thermal Attacks on Public Payment Terminals. www.usenix.org/conference/usen … 3/presentation/marky

Comment by Dr. Krishna Kumari Challa on August 11, 2023 at 10:30am

Repairing the heart with silicon nanowires and stem cell cardiomyocytes

A research group  has developed a strategy to improve heart repair using human pluripotent stem cell–derived cardiomyocytes combined with biodegradable and biocompatible electroconductive silicon nanowires.

In the paper, "Nanowired human cardiac organoid transplantation enables highly efficient and effective recovery of infarcted hearts," published in Science Advances, the authors detail how cells self-assemble to form organoids that mimic fundamental cardiac tissue–level functions and contain vascular networks that reduce the risk of apoptosis during oxygen deprivation.

Nanowired cardiac organoids, tiny living and contracting orbs of heart tissue with microscopic wires embedded, were fabricated from human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) and cultured along with electroconductive silicon nanowires (e-SiNWs) so that the wires were integrated into the tissues. The engineered spheres were then injected into damaged and dying tissues of rat hearts.

While the use of cardiac organoids for tissue repair is not new, there have been limitations of low cell retention at the repair site, leading to moderate functional improvements and scalability issues.

The addition of nanowires increased the conductivity of the tissues, allowing them to synchronize better, facilitating better communication among cells and integration with the existing heart tissue.

Nanowired organoids achieved double the functional recovery in the rats, with a lower number of engrafted cells (~0.5 × 10⁶ hPSC-CMs per rat) compared to previous studies without nanowires in the hPSC-CMs (~10 × 10⁶ hPSC-CMs per rat).

Integrating e-SiNWs did not exacerbate inflamatory responses in healthy or damage repair settings, as expected from the biocompatible nature of silicon.

Nanowired cardiac organoids also exhibited significantly less apoptosis than wireless cardiac spheroids.

Yu Tan et al, Nanowired human cardiac organoid transplantation enables highly efficient and effective recovery of infarcted hearts, Science Advances (2023). DOI: 10.1126/sciadv.adf2898

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