Comment

Comment by Dr. Krishna Kumari Challa on June 5, 2021 at 7:36am

New form of silicon could enable next-gen electronic and energy devices

A research team developed a new method for synthesizing a novel crystalline form of silicon with a hexagonal structure that could potentially be used to create next-generation electronic and energy devices with enhanced properties that exceed those of the "normal" cubic form of silicon used today.

Like all elements, silicon can take different crystalline forms, called allotropes, in the same way that soft graphite and super-hard diamond are both forms of carbon. The form of silicon most commonly used in electronic devices, including computers and solar panels, has the same structure as diamond. Despite its ubiquity, this form of silicon is not actually fully optimized for next-generation applications, including high-performance transistors and some photovoltaic devices.

While many different silicon allotropes with enhanced physical properties are theoretically possible, only a handful exist in practice given the lack of known synthetic pathways that are currently accessible.

Thomas B. Shiell et al, Bulk Crystalline 4H-Silicon through a Metastable Allotropic Transition, Physical Review Letters (2021). DOI: 10.1103/PhysRevLett.126.215701

https://phys.org/news/2021-06-silicon-enable-next-gen-electronic-en...

Comment by Dr. Krishna Kumari Challa on June 5, 2021 at 6:40am

Deep-Earth microbes feed on radioactivity

Scientists have long puzzled over how microbes living deep underground feed themselves without sunlight or heat. Now, two studies suggest that these organisms could feed off the radioactive decay of hydrogen and other elements. The findings open up new possibilities for life on other worlds — and could shed some light on our planet’s own history.

--

Radioactivity May Fuel Life Deep Underground and Inside Other Worlds

New work suggests that the radiolytic splitting of water supports giant subsurface ecosystems of life on Earth — and could do it elsewhere, too.

https://www.quantamagazine.org/radioactivity-may-fuel-life-deep-und...

Comment by Dr. Krishna Kumari Challa on June 4, 2021 at 10:44am

COVID Sweat Sensor Catches Your Immune System Before It Goes Berserk 

Early in the COVID-19 pandemic, doctors recognized that patients who developed a surge of pro-inflammatory immune proteins, also known as a “cytokine storm,” were often the sickest and at the greatest risk of dying. While blood tests can measure cytokines, they can’t continuously monitor a patient’s protein levels. Researchers at EnliSense LLC and the University of Texas have developed a wristwatch-like device that can track cytokine levels through a patient’s sweat, allowing doctors time to proactively administer medicines like steroids if they see cytokine levels rising.

**

Comment by Dr. Krishna Kumari Challa on June 4, 2021 at 10:24am

Diard M, Bakkeren E, Lentsch V, Rocker A, Amare Bekele N, Hoces D, Aslani S, Arnoldini M, Böhi F, Schumann-​Moor K, Adamcik J, Piccoli L, Lanzavecchia A, Stadtmueller BM, Donohue N, van der Woude MW, Hockenberry A, Viollier PH, Falquet L, Wüthrich D, Bonfiglio F, Loverdo C, Egli A, Zandomeneghi G, Mezzenga R, Holst O, Meier BH, Hardt WD, Slack E: A rationally designed oral vaccine induces immunoglobulin A in the murine gut that directs the evolution of attenuated Salmonella variants. Nature Microbiology, 27 May 2021, doi: 10.1038/s41564-​021-00911-1

Evolutionary Trap Vaccines to combat drug resistant bacteria

The Spark Award 2020 of ETH Zurich stands for the most promising invention, which was filed for a patent in 2019. The presented technology is among the top 5 nominees.

Comment by Dr. Krishna Kumari Challa on June 4, 2021 at 10:23am

Luring bacteria into a trap

Developing vaccines against bacteria is in many cases much more difficult than vaccines against viruses. Like virtually all pathogens, bacteria are able to sidestep a vaccine's effectiveness by modifying their genes. For many pathogens, such genetic adaptations under selective pressure from vaccination will cause their virulence or fitness to decrease. This lets the pathogens escape the effects of vaccination, but at the price of becoming less transmissible or causing less damage. Some pathogens, however, including many bacteria, are extremely good at changing in ways that allow them to escape the effects of vaccination while remaining highly infectious. For scientists looking to develop vaccines, this kind of immune evasion has been a fundamental problem for decades. If they set out to develop vaccines against bacterial pathogens, often they will notice that these quickly become ineffective. Now, however, researchers have exploited precisely this mechanism to come up with an effective vaccine against bacteria. They succeeded in developing a Salmonella vaccine that, instead of trying to outright kill intestinal bacteria, rather guides their evolution in the gut to make them a weaker pathogen.

the researchers inoculated mice with a series of slightly different vaccines against Salmonella typhimurium, and observed how the Salmonella in the animals’ guts modified their genes to escape the vaccines’ effects. This let the scientists identify the full spectrum of possible immune evasion mutations in Salmonella typhimurium. Subsequently, the researchers produced a combination vaccine from four Salmonella strains that covered the bacteria’s full spectrum of genetic evasion options.

A surprising immune evasion was driven by this combined vaccine, causing an important Salmonella sugar coating on the surface to atrophy. While the affected bacteria were still able to multiply in the animals’ guts, they were largely unable to infect body tissues and cause disease. This is because the sugar coating is part of the bacteria’s protective coating that shields them from the host’s defences as well as from viruses that often infect and kill the bacteria. In tests on mice, the scientists were able to show that their new vaccine was more effective at preventing Salmonella infections than existing vaccines approved for use in pigs and chickens.

The scientists now plan to use the same principle to develop vaccines against other microorganisms – for example, against antimicrobial-​resistant bacterial strains. In addition, it ought to be possible to use the approach in biotechnology and bring about specific modifications in microorganisms by exerting selective pressure through vaccines.

https://ethz.ch/en/news-and-events/eth-news/news/2021/06/luring-bac...

Comment by Dr. Krishna Kumari Challa on June 4, 2021 at 10:11am

Scientists make powerful underwater glue inspired by barnacles and mussels

A new type of glue inspired by the stubbornly adherent crustaceans has been developed by researchers.

Starting with the fibrous silk protein harvested from silkworms, they were able to replicate key features of barnacle and mussel glue, including protein filaments, chemical crosslinking and iron bonding. The result is a powerful non-toxic glue that sets and works as well underwater as it does in dry conditions and is stronger than most synthetic glue products now on the market.

The Silklab "glue crew" focused on several key elements to replicate in aquatic adhesives. Mussels secrete long sticky filaments called byssus. These secretions form polymers, which embed into surfaces, and chemically cross-link to strengthen the bond. The protein polymers are made up of long chains of amino acids including one, dihydroxyphenylalanine (DOPA), a catechol-bearing amino acid that can cross-link with the other chains. The mussels add another special ingredient—iron complexes—that reinforce the cohesive strength of the byssus.

Barnacles secrete a strong cement made of proteins that form into polymers which anchor onto surfaces. The proteins in barnacle cement polymers fold their amino acid chains into beta sheets—a zig-zag arrangement that presents flat surfaces and plenty of opportunities to form strong hydrogen bonds to the next protein in the polymer, or to the surface to which the polymer filament is attaching.

Michael A. North et al. High Strength Underwater Bonding with Polymer Mimics of Mussel Adhesive Proteins, ACS Applied Materials & Interfaces (2017). DOI: 10.1021/acsami.7b00270

https://phys.org/news/2021-06-scientists-powerful-underwater-barnac...

https://phys.org/news/2017-03-biomimetic-high-strength-bonding.html

Biomimetic Underwater Glue

Comment by Dr. Krishna Kumari Challa on June 3, 2021 at 9:05am

Deadly river ‘earthquakes’ could be manageable

Comment by Dr. Krishna Kumari Challa on June 3, 2021 at 7:59am

What if the black hole at the center of the Milky Way is actually a...

A team of researchers at the International Center for Relativistic Astrophysics has found evidence that suggests Sagittarius A* is not a massive black hole but is instead a mass of dark matter. In their paper published in the journal Monthly Notices of the Royal Astronomical Society: Letters, the group describes the evidence they found and how it has stood up to testing.

Comment by Dr. Krishna Kumari Challa on June 3, 2021 at 7:40am

Atmospheric metal layers appear with surprising regularity

Twice a day, at dusk and just before dawn, a faint layer of sodium and other metals begins sinking down through the atmosphere, about 90 miles high above the city of Boulder, Colorado. The movement was captured by one of the world's most sensitive "lidar" instruments and reported recently in the AGU journal Geophysical Research Letters.

The metals in those layers come originally from rocky material blasting into Earth's atmosphere from space, and the regularly appearing layers promise to help researchers understand better how earth's atmosphere interacts with space, even potentially how those interactions help support life.

This is an important discovery because we have never seen these dusk/dawn features before, and because these metal layers affect many things. The metals can fall into the ocean and act as fertilizer for ecosystems, the ionized metals can affect GPS radio signals.

It is the first time that the metal layers—which are not harmful to people—have been seen so regularly at these extreme heights in the atmosphere. Such high-altitude metal layers were discovered by Chu's group just 10 years ago above McMurdo, Antarctica, but there they occur more sporadically. Above Boulder, they're consistent, daily, and synched with winds that occur high in the atmosphere.

Xinzhao Chu et al, Mid‐Latitude Thermosphere‐Ionosphere Na (TINa) Layers Observed With High‐Sensitivity Na Doppler Lidar Over Boulder (40.13°N, 105.24°W), Geophysical Research Letters (2021). DOI: 10.1029/2021GL093729

https://phys.org/news/2021-06-atmospheric-metal-layers-regularity.h...

Comment by Dr. Krishna Kumari Challa on June 3, 2021 at 6:54am

Human brain and testis found to have the highest number of common proteins

A team of researchers  has found that for humans, the brain and testis have the highest number of common proteins. In their paper published in the journal Royal Society Open Biology, the group describes their study of protein similarities between tissues.

In this new effort, the researchers noted that evidence from other studies has found some signs of similarities between testis and the human brain. Intrigued, they initiated a study that involved analyzing the proteins produced by different parts of the body and then comparing them to see similarities. The researchers found the greatest similarities between the brain and testicles—13,442 of them. This finding suggests that the brain and the testicles share the highest number of genes of any organs in the body.

The team next focused on the shared proteins and found that most of them were involved in the development of tissue and communications. They suggest this finding was not surprising, considering that proteins from both organs consume high amounts of fuel—one to process thinking, the other to produce millions of sperm every day. They also note that testis and nerve cells are both involved in moving material created inside of them to an outside environment—sperm cells move fertilization factors and neurons move neurotransmitters. Both are part of processes known as exocytosis. Additionally, as part of exocytosis, sperm allow parts of themselves to fuse with an egg. With neurons, exocytosis involves creating neurites that allow for communication between cells.

Bárbara Matos et al, Brain and testis: more alike than previously thought?, Open Biology (2021). DOI: 10.1098/rsob.200322

https://phys.org/news/2021-06-human-brain-testis-highest-common.htm...

• ‹ Previous
• 1
• …
• 672
• 673
• 674
• 675
• 676
• …
• 1134
• Next ›
• Page