Comment

Comment by Dr. Krishna Kumari Challa on December 14, 2023 at 10:01am

Newly created ultra-hard material rivals diamond

Scientists have solved a decades-long puzzle and unveiled a near unbreakable substance that could rival diamond as the hardest material on Earth. The research is published in the journal Advanced Materials. Researchers found that when carbon and nitrogen precursors were subjected to extreme heat and pressure, the resulting materials—known as carbon nitrides—were tougher than cubic boron nitride, the second hardest material after diamond.

The breakthrough opens doors for multifunctional materials to be used for industrial purposes including protective coatings for cars and spaceships, high-endurance cutting tools, solar panels and photodetectors, experts say.

Materials researchers have attempted to unlock the potential of carbon nitrides since the 1980s, when scientists first noticed their exceptional properties, including high resistance to heat.

Researchers subjected various forms of carbon nitrogen precursors to pressures of between 70 and 135 gigapascals—around 1 million times our atmospheric pressure—while heating it to temperatures of more than 1,500°C.

To identify the atomic arrangement of the compounds under these conditions, the samples were illuminated by an intense X-ray beam at three particle accelerators—the European Synchrotron Research Facility in France, the Deutsches Elektronen-Synchrotron in Germany and the Advanced Photon Source based in the United States.

Researchers discovered that three carbon nitride compounds were found to have the necessary building blocks for super-hardness.

Remarkably, all three compounds retained their diamond-like qualities when they returned to ambient pressure and temperature conditions.

Further calculations and experiments suggest the new materials contain additional properties including photoluminescence and high energy density, where a large amount of energy can be stored in a small amount of mass.

Researchers say the potential applications of these ultra-incompressible carbon nitrides is vast, potentially positioning them as ultimate engineering materials to rival diamonds.

Dominique Laniel et al, Synthesis of Ultra‐Incompressible and Recoverable Carbon Nitrides Featuring CN4 Tetrahedra, Advanced Materials (2023). DOI: 10.1002/adma.202308030

Comment by Dr. Krishna Kumari Challa on December 13, 2023 at 11:56am

Read the original article.

**

Comment by Dr. Krishna Kumari Challa on December 13, 2023 at 11:54am

Climate change research: If warming approaches 2°C, a trickle of extinctions will become a flood

As delegates discuss the climate crisis in Dubai for COP28, the dazzling variety of life found on Earth hangs in the balance.

Our world has warmed by roughly 1.2°C since the pre-industrial period. Many species are already exposed to increasingly intolerable conditions, driving some populations to die off or contract at the hottest edges of their geographic ranges. Biodiversity is feeling the heat in all ecosystems and regions, from mountain tops to ocean depths.

If all national plans to cut emissions are fulfilled, the world would still be on track for 2.5 to 2,9 C of global warming by the end of the century. If species are stressed now, imagine how they will fare over the coming decades.

Are there thresholds of warming beyond which the risks to wildlife accelerate? And if so, where and when might we cross them? In short, what does the future hold for Earth's biodiversity?

Answering these questions has been tricky. Computer simulations that attempt to model how biodiversity will behave in a  warming world have only compared the current status of species to how it may look at a particular point in the future, such as 2050 or 2100.

In a recent paper, researchers studied how the area over which species are exposed to potentially dangerous temperatures will expand from one year to the next, from now until the end of the century.

They overlaid the projections of climate models with data on the geographic distributions of more than 35,000 species on land and in the ocean. We found that the area over which each species will be exposed to intolerable temperatures is likely to increase abruptly during the coming decades.

Most populations may initially appear safe. But then, suddenly, a threshold of global warming is crossed beyond which multiple populations across widespread areas face intolerable conditions in rapid succession.

Of the populations within a species projected to be at risk this century, researchers found that, on average, more than half will switch from being relatively safe to facing dangerous heat in as little as a single decade. A good example is Coral Reefs. Just a few decades ago, coral bleaching events driven by extreme sea surface temperatures were rare and localized. Today, these events degrade reefs globally on an almost annual basis.

The sudden increase in risk to species that scientists' models project is in part due to the rapid pace of global warming itself. When combined with natural variability in the climate (El Niño events are one example), warming tends to raise regional temperatures in sudden jumps rather than smooth inclines.

However, they also found that these thermal thresholds are sharpened by the shape of the planet. For instance, across the Amazon basin in South America, temperatures are similarly hot from one place to another. If one population of a species exceeds its thermal limit, it will also be exceeded across many other populations simultaneously.

https://www.nature.com/articles/s41559-023-02070-4.epdf?sharing_tok...

 

Comment by Dr. Krishna Kumari Challa on December 13, 2023 at 11:46am

Study shows how hurricane acted as a highway to transport microplas...

When a hurricane approaches and crosses land, severe damage can occur—often leaving an obvious trail of physical destruction. What's less obvious to the naked eye is how these storms can carry harmful microplastics across the world.

Wildfires can unlock toxic metal particles from soils, study finds

Wildfires can transform a benign metal in soils and plants into toxic particles that easily become airborne, according to a new study from Stanford University.

Scientists develop environment-friendly and cost-effective approach...

A group of scientists have discovered a new application to generate and store chilled water to reduce the impact of air conditioning on the environment, reduce energy consumption, and lower dependence on fossil fuels.

Comment by Dr. Krishna Kumari Challa on December 13, 2023 at 11:37am

Patients told to get pregnant to treat endometriosis by doctors despite lack of evidence: Research 

Research shows patients with endometriosis are being told to plan a pregnancy to help manage or treat the condition, despite a lack of evidence to show it reduces symptoms. The controversial advice has prompted calls to improve medical education about endometriosis.

More than 3,000 medically diagnosed patients were surveyed across the globe as part of the collaborative study involving researchers and a not-for-profit charity focusing on awareness, information, and advocacy.

The research, which focused on patient experiences, revealed more than half (1,892 of 3,347 total) were advised to fall pregnant or have a baby to manage or treat endometriosis, which can include severe pelvic pain and infertility. Almost 90% (1,691 of 1,892) of endometriosis patients were given this recommendation by health care professionals, including gynecologists and GPs, with 36% told it would cure their condition.

Pregnancy or having a baby isn't a treatment for endometriosis and this advice from health professionals can have negative impacts on those who receive it, according to scientists.

While a third of the respondents felt the advice was appropriate given their situation at the time, many other women in this survey reported feeling too young to have a baby and felt stressed and pressured after being given this inappropriate albeit well-intentioned advice.

Some of the patient responses from the research paper, which has been published in BMC Women's Health , include: "I was 21, single and at uni so it simply wasn't an option" and "I was 13. It wasn't appropriate."

The research also revealed the life-altering impact this advice had on the mental health of patients, their relationships, major life decisions and their trust in the health care system.

"It ended up ruining my relationship as I felt a huge pressure to have kids young and my partner couldn't understand this intense conversation at a young age," said one respondent.

The European Society for Human Reproduction Embryology (ESHRE) Guidelines for Management of Endometriosis state that patients should not be advised to become pregnant with the sole purpose of treating endometriosis, as pregnancy does not always lead to improvement of symptoms or reduction of disease progression.

 Diksha Sirohi et al, Patient experiences of being advised by a healthcare professional to get pregnant to manage or treat endometriosis: a cross-sectional study, BMC Women's Health (2023). DOI: 10.1186/s12905-023-02794-2

Comment by Dr. Krishna Kumari Challa on December 13, 2023 at 10:26am

Brain tissue on a chip achieves voice recognition

Clusters of lab-raised brain cells connected to a computer are capable of elementary speech recognition and math problems.

his study by Bio-engineers  is a major step in demonstrating how brain-inspired computer neural networks can advance artificial intelligence capabilities.

Researchers grew bundles of specialized stem  cells that developed into neurons, the main component of the brain. A typical brain consists of 86 billion neurons, each neuron connected to as many as 10,000 other neurons.

The ball of neurons, known as an organoid, created in their lab is less than a nanometer wide. It was connected by an array of electrodes to a circuit board, where machine-learning algorithms decoded responses from the organoid.

The researchers dubbed their creation Brainoware.

After a brief training period, Brainoware was able to distinguish between the voices of eight subjects based on their varying pronunciation of vowels. The system achieved an accuracy rate of 78%.

Brainoware was also able to successfully predict a Henon map, a mathematical construct in the field of chaotic dynamics, with greater accuracy than an artificial network.

This is a first demonstration of using brain organoids [for computing]. It's exciting to see the possibilities of organoids for biocomputing in the future, say the researchers. 

A key advantage of biocomputing is its energy efficiency. Currently, artificial neural networks consume several million watts of energy a day. The human brain, on the other hand, requires only about 20 watts to function for a day. Brainoware is a bridge between AI and organoids.

Challenges remain. Among them will be the task of keeping organoids healthy and well-nourished, a 24/7 task.

And there are other concerns as well.

As the sophistication of these organoid  systems increases, it is critical for the community to examine the myriad of neuroethical issues that surround biocomputing systems incorporating human neural tissue.

Hongwei Cai et al, Brain organoid reservoir computing for artificial intelligence, Nature Electronics (2023). DOI: 10.1038/s41928-023-01069-w

Lena Smirnova et al, Reservoir computing with brain organoids, Nature Electronics (2023). DOI: 10.1038/s41928-023-01096-7

Comment by Dr. Krishna Kumari Challa on December 12, 2023 at 12:54pm

Green spaces are well known to mitigate stresses in many ways. Plants help protect and insulate us from the environment, keeping our surrounds up to several degrees cooler during heat waves. They decrease air and noise pollution.

Green spaces encourage physical activity and social interactions and are associated with lower risk of crime.

Yet at the same time we've been learning just how intrinsically reliant our minds and bodies are on the natural world.

https://www.sciencedirect.com/science/article/pii/S0048969723060795...

Part 2

Comment by Dr. Krishna Kumari Challa on December 12, 2023 at 12:53pm

People Living in Green Areas Seem to Age Slower at The Cellular Level

Surrounding ourselves with nature does wonders for our bodies, from better mental health to healthier hearts and stronger developing immune systems. So much so that some doctors are literally prescribing nature as a treatment.

New research may have found a potential explanation for some of these benefits: People living in areas surrounded by nature tend to have younger biological ages.

This study was an attempt to quantify the beneficial impacts of greenspace at the cellular level, and the extent to which greenspace can help to offset environmental harms.

Examining 7,827 people and their home environments, the researchers found those living in areas filled with more parks, gardens, trees, and other vegetation had longer telomeres – a region in DNA sequences associated with longevity.

That was true regardless of race, economic status, whether they were drinkers or smokers.

Telomeres are repeating sections of DNA found at the ends of each of our 46 chromosomes, preventing the genetic molecule from unraveling like the plastic ends of shoelaces.

Each time a cell divides the telomeres inside them become shorter, until the cell can no longer divide its genetic material and its cell line dies out.

This makes telomeres important markers of biological age, or how worn down our cells are. We know that many variables – such as stress – can influence how quickly our telomeres wear down.

Part 1

Comment by Dr. Krishna Kumari Challa on December 12, 2023 at 12:46pm

Researchers decided to focus on microRNA genes due to their simple structure: the genes are very short—just a few tens of bases—and they have to fold into a hairpin structure to function correctly.

A central insight was to model the gene history using a custom computer algorithm. This enables the closest inspection of the origin of genes thus far.

The whole genome of tens of primates and mammals is known. A comparison of their genomes reveals which species have the microRNA palindrome pair and which lack it. With a detailed modeling of the history, they could see that whole palindromes are created by single mutation events.

By focusing on humans and other primates, researchers  demonstrated that the newly found mechanism can explain at least a quarter of the novel microRNA genes. As similar cases were found in other evolutionary lineages, the origin mechanism appears universal.

In principle, the rise of microRNA genes is so easy that novel genes could affect human health. 

The emergence of new genes from nothing has fascinated researchers. Although the results are based on small regulatory genes, researchers think that the findings can be generalized to other RNA genes and molecules.

 Heli A. M. Mönttinen et al, Generation of de novo miRNAs from template switching during DNA replication, Proceedings of the National Academy of Sciences (2023). DOI: 10.1073/pnas.2310752120

Part 2

Comment by Dr. Krishna Kumari Challa on December 12, 2023 at 12:43pm

New genes found that can arise 'from nothing'

The complexity of living organisms is encoded within their genes, but where do these genes come from? Researchers  resolved outstanding questions around the origin of small regulatory genes, and described a mechanism that creates their DNA palindromes. Under suitable circumstances, these palindromes evolve into microRNA genes.

The human genome contains ca. 20,000 genes that are used for the construction of proteins. Actions of these classical genes are coordinated by thousands of regulatory genes, the smallest of which encode microRNA molecules that are 22 base pairs in length. While the number of genes remains relatively constant, occasionally, new genes emerge during evolution. Similar to the genesis of biological life, the origin of new genes has continued to fascinate scientists.

All RNA molecules require palindromic runs of bases that lock the molecule into its functional conformation. Importantly, the chances of random base mutations gradually forming such palindromic runs are extremely small, even for the simple microRNA genes.

Hence, the origin of these palindromic sequences has puzzled researchers till now. Experts  now resolved this mystery, describing a mechanism that can instantaneously generate complete DNA palindromes and thus create new microRNA genes from previously noncoding DNA sequences.

In their project, the researchers studied errors in DNA replication. DNA replication can be compared to typing of text. DNA is copied one base at a time, and typically mutations are erroneous single bases, like mis-punches on a laptop keyboard. So researchers studied a mechanism creating larger errors.

Researchers recognized that DNA replication errors could sometimes be beneficial. Some researchers saw the connection to the structure of RNA molecules.

In an RNA molecule, the bases of adjacent palindromes can pair and form structures resembling a hairpin. Such structures are crucial for the function of the RNA molecules.

Part 1

• ‹ Previous
• 1
• …
• 303
• 304
• 305
• 306
• 307
• …
• 1082
• Next ›
• Page