Comment

Comment by Dr. Krishna Kumari Challa on May 20, 2023 at 10:02am

Scientists urge crackdown on methane emissions with only 13% regulated

New research  shows that only around 13% of global methane emissions are regulated, despite methane emissions causing at least 25% of current global warming.

The global review, published on May 19 in One Earth, also found that little is known about the effectiveness of the policies that exist, with potentially unrepresentative methane emission estimations used rather than actual measurements. Inaccurate estimations can also mean the issue is taken less seriously by decision-makers by masking its severity.

The researchers argue that the lack of regulation and clarity into their impact must urgently be addressed if we are to meet our global climate targets. The review suggests a consistent approach worldwide with robust quantification and reporting could unlock new opportunities to drastically reduce global warming levels.

To meet the Paris Agreement 1.5°C objective, man-made methane emissions should be reduced by at least 40%–45% by 2030, compared to the 2020 levels. Methane mitigation is not only a cost-effective strategy to reduce global warming but could also improve the air quality. Today methane emissions are increasing faster than at any time since the 1980s.

A global review of methane policies reveals only 13% of emissions are covered with unclear effectiveness, One Earth (2023). DOI: 10.1016/j.oneear.2023.04.009

Comment by Dr. Krishna Kumari Challa on May 20, 2023 at 9:39am

Many genes implicated in critical COVID-19 are highly expressed in the monocyte-macrophage system, which has poor coverage in existing expression quantitative trait loci datasets. Macrophages synthesize many substances involved in host defense and inflammation and play a pivotal role in immune system reactions.

Additionally, the investigation found variation in circulating protein levels with 15 unique proteins linked to critical illness and some with well-studied biomarkers that make them good candidates for drug targeting.

The research has identified several potential druggable targets in multiple systems, including inflammatory signaling, monocyte-macrophage activation and endothelial permeability. Some of the targets found have already seen positive results with therapeutic signals in multiple drug trials, providing a good proof-of-concept for drug target identification using comparative genetics.

 Erola Pairo-Castineira et al, GWAS and meta-analysis identifies 49 genetic variants underlying critical COVID-19, Nature (2023). DOI: 10.1038/s41586-023-06034-3

Part2

**

Comment by Dr. Krishna Kumari Challa on May 20, 2023 at 9:39am

A global effort to identify critical illness in some COVID-19 patients highlights genetic risk, potential treatments

Researchers  have led a study in collaboration with scientists worldwide, looking into cases of critical illness in COVID-19 patients.

Critical illness in COVID-19 is an extreme and clinically consistent disease phenotype the team has found presenting in patients with shared genetic attributes. These shared genetics hint at a shared mechanism for the critical illness not seen in other patients and potential therapies to address the condition.

Patients with confirmed COVID-19 and requiring continuous cardiorespiratory monitoring or organ support (a generalizable definition for critical illness) were recruited in 2020–2022.

Researchers analyzed 24,202 cases of COVID-19 with critical illness with a combination of microarray genotyping and whole-genome sequencing data from the international GenOMICC study (11,440 cases) and other studies recruiting hospitalized patients with severe and critical illness, including the COVID-19 Human Genetics Initiative, the International Severe Acute Respiratory and Emerging Infection Consortium, the Spanish Coalition to Unlock Research on Host Genetics consortium and 23andMe.

The team found 49 genome-wide significant associations, of which 16 have not been reported previously and 196 significantly associated genes in a gene-level analysis. Although the implicated variants are not directly causing illness in the patients, they can highlight molecular mechanisms that make some COVID-19 infections much more severe. The findings are published in the journal Nature.

Part 1

Comment by Dr. Krishna Kumari Challa on May 19, 2023 at 11:48am

Human evolution has no single birthplace

Humans did not emerge from a single region of Africa, but from several populations that moved around the continent one millio... and intermingled for millennia. The widely held idea of a single origin of Homo sapiens is based in part on fossil records. Computer modelling and genome data from modern African and European populations revealed that “our roots lie in a very diverse overall population made up of fragmented local populations”, says evolutionary archaeologist Eleanor Scerri. This means human evolution looks more like a tangled vine than a ‘tree of life.’

https://www.nature.com/articles/s41586-023-06055-y.epdf?sharing_tok...

Human-evolution story rewritten by fresh data and more computing power

Humans did not emerge from a single region of Africa, suggests a powerful modelling study. Rather, our ancestors moved and intermingled for millennia.

https://www.nature.com/articles/d41586-023-01664-z?utm_source=Natur...

Comment by Dr. Krishna Kumari Challa on May 19, 2023 at 11:19am

Half of the world's largest lakes are losing water

More than 50% of the largest lakes in the world are losing water, according to a new assessment published recently in Science . The key culprits are not surprising: warming climate and unsustainable human consumption.

Researchers combined three decades of observations from an array of satellites with models to quantify and attribute trends in lake storage globally.

For the new paper, the team used 250,000 lake-area snapshots captured by satellites between 1992–2020 to survey the area of 1,972 of Earth's biggest lakes. They collected water levels from nine satellite altimeters and used long-term water levels to reduce any uncertainty. For lakes without a long-term level record, they used recent water measurements made by newer instruments on satellites. Combining recent level measurements with longer-term area measurements allowed scientists to reconstruct the volume of lakes dating back decades.

The results were staggering: 53% of lakes globally experienced a decline in water storage. 

Lakes in both dry and wet areas of the world are losing volume. The losses in humid tropical lakes and Arctic lakes indicate more widespread drying trends than previously understood.

Researchers also assessed storage trends in reservoirs. They found that nearly two-thirds of Earth's large reservoirs experienced significant water losses.

Sedimentation dominated the global storage decline in existing reservoirs. In long-established reservoirs—those that filled before 1992—sedimentation was more important than droughts and heavy rainfall years.

 Fangfang Yao, Satellites reveal widespread decline in global lake water storage, Science (2023). DOI: 10.1126/science.abo2812. www.science.org/doi/10.1126/science.abo2812

Comment by Dr. Krishna Kumari Challa on May 19, 2023 at 10:45am

Researchers transform our understanding of crystals

When most people think of crystals, they picture suncatchers that act as rainbow prisms or the semi-transparent stones that some believe hold healing powers. However, to scientists and engineers, crystals are a form of materials in which their constituents—atoms, molecules, or nanoparticles—are arranged regularly in space. In other words, crystals are defined by the regular arrangement of their constituents. Common examples are diamonds, table salt, or sugar cubes.

However, in research just published in Soft Matter, a team  of researchers discovered that crystal structures are not necessarily always regularly arranged. The discovery advances the field of materials science and has unrealized implications for the materials used for semiconductors, solar panels, and electric vehicle technologies.

One of the most common and important classes of crystal structures is the close-packed structures of regular spheres constructed by stacking layers of spheres in a honeycomb arrangement. There are many ways to stack the layers to construct close-packed structures, and how nature selects specific stacking is an important question in materials and physics research. In the close-packing construction, there is a very unusual structure with irregularly spaced constituents known as the random stacking of two-dimensional hexagonal layers (RHCP). This structure was first observed from cobalt metal in 1942, but it has been regarded as a transitional and energetically unpreferred state.

Researchers now  collected X-ray scattering data from soft model nanoparticles made of polymers and realized that the scattering data contains important results about RHCP but is very complicated.

What they found 's that the RHCP structure is, very likely, a stable structure, and this is the reason that RHCP has been widely observed in many materials and naturally occurring crystal systems. This finding challenges the classical definition of crystals. 

The study provides insights into the phenomenon known as polytypism, which enables the formation of RHCP and other close-packed structures. A representative material with polytypism is silicon carbide, widely used for high-voltage electronics in electric vehicles and as hard materials for body armor. These new  findings indicate that those polytypic materials may have continuous structural transitions, including the non-classical random arrangements with new useful properties.

 Juhong Ahn et al, Continuous transition of colloidal crystals through stable random orders, Soft Matter (2023). DOI: 10.1039/D3SM00199G

Comment by Dr. Krishna Kumari Challa on May 19, 2023 at 10:09am

Humans were making fires at least 250,000 years ago in Europe, research finds

Early humans in Europe were making and controlling fire at least 50,000 years earlier than previously thought, researchers have found.

In a paper published in the journal, Scientific Reports, the scientists set out evidence that our ancestors in Europe were using fires for activities like cooking, heating and defense at least 250,000 years ago. Previous evidence had suggested humans were managing fire in Europe much later than this, around 200,000 years ago.

Using forensic chemical methods to identify molecules of incomplete burning, the research team detected fire at Valdocarros II, an archaeological site near Madrid in Spain.

Researchers have found definitive evidence of things being burnt and those remains are organized into a pattern, suggesting it's humans who are making and controlling the fire. Either they were using the fire to cook or to defend themselves. The spatial patterning in the fire tells us that they were encircling something, like a home or sleeping area, a living room or kitchen, or an enclosure for animals.

The chemical profiles of the charred remains also suggest our human ancestors chose certain types of firewood for its burning properties, such as heat and lack of smoke.

The findings are "very exciting" and close a gap in our understanding of human-controlled fire and human development.

This is important because our species is defined by our use of fire. Being able to cook food to feed our big brains is one of the things that made us so successful in an evolutionary sense. Fire also brings protection and fosters communication and family connection. And scientists now have definitive, incontrovertible evidence that humans were starting and stopping fires in Europe about 50,000 years earlier than researchers suspected.

Clayton Magill et al, Organic geochemical evidence of human‑controlled fires at Acheulean site of Valdocarros II (Spain, 245 kya), Scientific Reports (2023). DOI: 10.1038/s41598-023-32673-7

**

Comment by Dr. Krishna Kumari Challa on May 18, 2023 at 3:31pm

Cosmic Cycles: Earth, Our Home

Comment by Dr. Krishna Kumari Challa on May 18, 2023 at 3:27pm

Human DNA is everywhere. That's a boon for science, and an ethical quagmire

In the water, on the land, in the air. In most cases the quality of DNA is almost equivalent to if you took a sample from a person.

We  cough, spit, shed and flush our DNA into all of these places and countless more. Signs of human life can be found nearly everywhere, short of isolated islands and remote mountaintops, according to a new  study.

That ubiquity is both a scientific boon and an ethical dilemma, say the UF researchers who sequenced this widespread DNA. The DNA was of such high quality that the scientists could identify mutations associated with disease and determine the genetic ancestry of nearby populations. They could even match genetic information to individual participants who had volunteered to have their errant DNA recovered.

Ethically handled environmental DNA samples could benefit fields from medicine and environmental science to archaeology and criminal forensics. For example, researchers could track cancer mutations from wastewater or spot undiscovered archaeological sites by checking for hidden human DNA. Or detectives could identify suspects from the DNA floating in the air of a crime scene.

But this level of personal information must be handled extremely carefully. Now, scientists and regulators must grapple with the ethical dilemmas inherent in accidentally—or intentionally—sweeping up human genetic information, not from blood samples but from a scoop of sand, a vial of water or a person's breath.

Published May 15 in Nature Ecology and Evolution, a paper by researchers outlines the relative ease of collecting human DNA nearly everywhere they looked.

Because of the ability to potentially identify individuals, the researchers say that ethical guardrails are necessary for this kind of research. The study was conducted with approval from the institutional review board of UF, which ensures that ethical guidelines are adhered to during research studies.

1. Liam Whitmore, Mark McCauley, Jessica A. Farrell, Maximilian R. Stammnitz, Samantha A. Koda, Narges Mashkour, Victoria Summers, Todd Osborne, Jenny Whilde, David J. Duffy. Inadvertent human genomic bycatch and intentional capture raise beneficial applications and ethical concerns with environmental DNA. Nature Ecology & Evolution, 2023; DOI: 10.1038/s41559-023-02056-2

**

Comment by Dr. Krishna Kumari Challa on May 18, 2023 at 7:15am

WHO warns against artificial sweeteners

Sweeteners don’t help people to lose weight in the long run and could increase the risk of type 2 diabetes and cardiovascular diseases if consumed continuously, the World Health Organization (WHO) advises. The guideline includes both artificial and natural sweeteners, such as aspartame and stevia. But it’s conditional, in keeping with life’s complexities — the WHO isn’t warning against sweetened toothpaste, for example, or recommending a change for people with pre-existing diabetes. The announcement contradicts some findings that sweeteners are harmless, even if they don’t offer any health benefits.

https://www.who.int/publications/i/item/9789240073616?utm_source=Na...

• ‹ Previous
• 1
• …
• 406
• 407
• 408
• 409
• 410
• …
• 1110
• Next ›
• Page