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Comment by Dr. Krishna Kumari Challa on September 20, 2023 at 6:31am

Research finds ponds release more greenhouse gas than they store

Though human-made ponds both sequester and release greenhouse gases, when added up, they may be net emitters, according to two related studies by  researchers.

The studies begin to quantify the significant effects that both human-made and natural ponds have on the global greenhouse gas budget, measurements that aren't well understood. Global climate models and predictions rely on accurate accounting of greenhouse gas emissions and carbon storage.

In the study, the researchers examined the past management activities, while also taking sediment cores and measurements of sediment thickness for each of the 22 study ponds. They measured the amount of carbon in the sediment, extrapolated those measurements to the overall pond, and divided that number by the age of the pond to arrive at the amount of carbon sequestered annually per square meter, a number on the same order of magnitude as wetlands and mangroves, and more than lakes. They also found that carbon burial rates were influenced by aquatic plants (those large enough to be seen), fish and additions of high nitrogen levels relative to phosphorus, nutrients that may not get renewed in a static pond and become limited. The right kinds and ratios of added nutrients promote plant growth, which use carbon for cells, and are deposited on the pond floor when plants die.

The  researchers also measured gas emissions from the ponds approximately every two weeks over the course of ice-free period in 2021.

The researchers found that methane—a greenhouse gas 25 times more potent than carbon dioxide—accounted for most of the gas emitted annually, and carbon dioxide and methane emissions varied greatly by season.

Ponds absorbed CO2 during early summer months when plants were growing, and emitted it later in the year, when plants decomposed. Methane was emitted throughout warm months, but week-to-week shifts in emissions were high, pointing to the need for frequent sampling for accurate accounting.

Part 1

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

Scientists Invented a Super-Slippery Toilet That Nothing Sticks to

The traditional porcelain and ceramic toilet bowls could be on the way out, if a new3D printed design from scientists  catches on – with the key benefit being the ultra slippery surface.

Poop that clings to the toilet bowl is not only unpleasant for bathroom visitors and cleaners alike, it actually wastes a significant amount of water as more flushes are required to dislodge the stuff.

It was this problem that the scientists wanted to tackle by making a non-stick toilet bowl. They used a mixture of plastic and hydrophobic sand grains for their material, fused together with laser-based 3D printing techniques, in a design that was around a tenth the size of a standard toilet bowl.

The abrasion-resistant super-slippery flush toilet, or ARSFT, was shown to repel synthetic feces, as well as multiple substances that the scientists tested. Nothing was able to get a grip on the surface, and everything slid straight down, much like the slippery pitcher plants that inspired the toilet design.

The as-prepared ARSFT remains clean after contacting with various liquids such as milk, yogurt, highly sticky honey, and starch gel mixed congee, demonstrating excellent repellence to complex fluids," write the researchers in their published paper.

https://onlinelibrary.wiley.com/doi/abs/10.1002/adem.202300703

Comment by Dr. Krishna Kumari Challa on September 19, 2023 at 10:30am

Study finds significant chemical exposures in women with cancer

In a sign that exposure to certain endocrine-disrupting chemicals may be playing a role in cancers of the breast, ovary, skin and uterus, researchers have found that people who developed those cancers have significantly higher levels of these chemicals in their bodies.

While it does not prove that exposure to chemicals like PFAS (per- and poly-fluoroalkyl substances) and phenols (including BPA) led to these cancer diagnoses, it is a strong signal that they may be playing a role and should be studied further.

The study showed that particularly for women, higher exposure to PFDE, a long-chained PFAS compound, had double the odds of a previous melanoma diagnosis; women with higher exposure to two other long-chained PFAS compounds, PFNA and PFUA, had nearly double the odds of a prior melanoma diagnosis.

The study showed a link between PFNA and a prior diagnosis of uterine cancer; and women with higher exposure to phenols, such as BPA (used in plastics) and 2,5-dichlorophenol (a chemical used in dyes and found as a by-product in wastewater treatment), had higher odds of prior ovarian cancer diagnoses.

The study concludes that Since PFAS make up thousands of chemicals, one way to reduce exposures is for EPA to regulate PFAS as a class of chemicals, rather than one at a time.

Cathey, A.L et al, Exploratory profiles of phenols, parabens, and per- and poly-fluoralkyl substances among NHANES study participants in association with previous cancer diagnoses, Journal of Exposure Science & Environmental Epidemiology (2023). DOI: 10.1038/s41370-023-00601-6

Comment by Dr. Krishna Kumari Challa on September 19, 2023 at 10:02am

Q: Why are the climate activists vandalizing art and museums?

Answer: "How do you feel when you see something beautiful and priceless art work apparently being destroyed before your eyes? Do you feel outraged? Good. Where is that feeling when you see the planet being destroyed?"

• A statement by a Just Stop Oil activist, who had taken part in vandalizing a work by Vermeer in The Hague

Lily Kinyon et al, When, where, and which climate activists have vandalized museums, npj Climate Action (2023). DOI: 10.1038/s44168-023-00054-5

Comment by Dr. Krishna Kumari Challa on September 19, 2023 at 9:54am

 The energy costs of information processing in biological systems

The behaviors, physiology and existence of living organisms is supported by countless biological processes, which entail the communication between cells and other molecular components. These molecular components are known to transmit information to each other in various ways, for instance via processes know as diffusion and electrical depolarization or by exchanging mechanical waves.

Researchers recently carried out a study aimed at calculating the energetic cost of this transfer of information between cells and molecular components. Their paper, published in Physical Review Letters, introduces a new tool that could be used to study cellular networks and better understand their function.

 They had tried to experimentally determine how much energy neurons spend when sending information. They  found that this energy expenditure ranged between 10⁴-10⁷ K_BT/bit depending on details, which is far higher than the 'fundamental' bound of ~ K_BT/bit, sometimes called the the Landauer bound which must be paid to erase a bit of information.

A further objective of the recent study was to determine whether optimizing these energetic costs could shed light on the reasons why molecular systems communicate with each other using distinct physical mechanisms in different situations. For instance, while neurons typically communicate with each other via electrical signals, other types of tells can communicate via the diffusion of chemicals.

They wanted to understand in what regime each of these (and others) would be best in terms of an energy cost per bit.

 Samuel J. Bryant et al, Physical Constraints in Intracellular Signaling: The Cost of Sending a Bit, Physical Review Letters (2023). DOI: 10.1103/PhysRevLett.131.068401

Comment by Dr. Krishna Kumari Challa on September 19, 2023 at 9:39am

Can a vitamin transform natural killer cells into a cancer therapy? Scientists think the answer is yes

Cancer patients appeared to benefit from natural killer cells obtained from donors in an experimental method of treating cancer that involved an aggressive army of immune system fighters endowed with the ability to home in on malignant cells and destroy them.

The natural killer cells were pre-treated with nicotinamide, a compound widely known to most people as niacin, or vitamin B₃. It's a substance with a special affinity for natural killer cells, enhancing their capacity to annihilate cancers. Once primed in the laboratory, these natural killers are ready to be unleashed against formidable targets. The evolving methodology has shown promise in a preliminary study aimed at forcing hard-to-treat cancers of the blood into remission.

Prior to the new research, which is published in Science Translational Medicine, attempts by other teams to use natural killer cell infusions as a therapeutic for leukemias, lymphomas and other blood malignancies, weren't always effective. Doctors were confronted with a problem: some people simply didn't respond to the investigational treatment, which was offered after standard therapy failed.

Now, in a unique take on this emerging form of cancer treatment, medical scientists have devised a way to boost the effectiveness of natural killer cells, enhancing their role as a therapeutic. The innovative approach boosted the impact of natural killer cells and brought about remissions in patients with otherwise recalcitrant cancers.

The combination of nicotinamide-enhanced natural killer cells and monoclonal antibody treatment was safe in 30 patients, including 20 with relapsed or difficult-to-treat non-Hodgkin lymphoma. Among 19 patients with non-Hodgkin lymphoma, 11 demonstrated a complete response and three had a partial response within 28 days of treatment. Nicotinamide appears to protect the natural killer cells from oxidative stress, while enhancing their ability to home in on lymph nodes, the scientists found.

Frank Cichocki et al, Nicotinamide enhances natural killer cell function and yields remissions in patients with non-Hodgkin lymphoma, Science Translational Medicine (2023). DOI: 10.1126/scitranslmed.ade3341

Comment by Dr. Krishna Kumari Challa on September 18, 2023 at 10:01am

Researchers took a fresh look at the flat ΛCDM concordance cosmology model as a potential source of mistaken assumptions. If cosmology was a game of chess, this would be the board and pieces as laid out on general relativity's tiles, moved by dark energy's push, and aligned by dark matter's gravitational influences.

Rewinding the chess pieces we see today, we can effectively see how the game began, from a momentary blink of rapid inflation to a time where the first stars collapse, to the formation of galaxies and their eventual emergence into gargantuan, interconnected threads.
If for some reason this process deviated from what's predicted by the concordance model, impeding the growth of the Universe's large-scale structure, the tension between the different measures of the Universe's accelerating expansion would vanish.

The researchers used a combination of measurements involving ripples in the cosmic web, gravitational lensing events, and details in the cosmic microwave background to come to a statistically convincing conclusion that the cosmic web is growing slower than the flat ΛCDM concordance cosmology model predicts.

"The difference in these growth rates that we have potentially discovered becomes more prominent as we approach the present day," says Nguyen.

"These different probes individually and collectively indicate a growth suppression. Either we are missing some systematic errors in each of these probes, or we are missing some new, late-time physics in our standard model."

While there are no obvious contenders for what might put the brakes on the growth of the cosmic web, future measurements of the Universe's large scale structure might at least hint at whether there's a need to explore the idea further.
The Universe has taken 13.7 billion years to look this good. We can stand to wait a few more years to work out the secrets to such fine looking cosmological wrinkles.

https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.131.111001

Part 2

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Comment by Dr. Krishna Kumari Challa on September 18, 2023 at 9:57am

Something Is Suppressing The Growth of The Universe, Physicists Say

Seen through a giant's eyes, our Universe's galaxies cling like foam to the surface of an eternal ocean, drawing into clumps and strings around inky voids. This sparkling web has taken eons to come together, congealing gradually under gravity's guidance out of what was, billions of years ago, an evenly-spread fog of white-hot particles fresh out of the Big Bang's oven.

Slow as this growth seems to us mere mortals, University of Michigan physicists Nhat-Minh Nguyen, Dragan Huterer, and Yuewei Wen want to slow it down even further, fixing one of science's most vexing problems in the process.
Their suggested tweak to the model that currently best describes our Universe could resolve a significant conflict in observations of space's expanding waistline.

Complain as you might that you can't get something for nothing these days, there's more empty space up there today than there was yesterday. Something is causing nothingness to grow, squeezing its way into the gaps between galaxies to gently push the large scale structure of the Universe apart at an ever increasing rate.
Since we don't know what is behind this mysterious shoving, we refer to it as dark energy.

"If gravity acts like an amplifier enhancing matter perturbations to grow into large-scale structure, then dark energy acts like an attenuator damping these perturbations and slowing the growth of structure," says Nguyen, the lead author of an investigation into the large-scale structure's growth.

"By examining how cosmic structure has been clustering and growing, we can try to understand the nature of gravity and dark energy."

The precise rate of expansion, known as the Hubble constant (H0), isn't at all clear. Measure the way certain kinds of exploding stars retreat into the distance, you might get an acceleration of 74 kilometers per second per megparsec. Using the 'light echo' of stretched radiation still bouncing about after the Big Bang – the cosmic microwave background (CMB) – H0 is closer to around 67 kilometers per second.

That might not seem like much of a difference, but the discrepancy has persisted through enough investigations that it can no longer be dismissed as some trivial error.
part1

Comment by Dr. Krishna Kumari Challa on September 18, 2023 at 9:26am

Matter found to comprise 31% of the total amount of matter and energy in the universe

One of the most interesting and important questions in cosmology is, "How much matter exists in the universe?" An international team of scientists has now succeeded in measuring the total amount of matter for the second time. Reporting in The Astrophysical Journal, the team determined that matter makes up 31% of the total amount of matter and energy in the universe, with the remainder consisting of dark energy.

Cosmologists think that only about 20% of the total matter is made of regular or 'baryonic' matter, which includes stars, galaxies, atoms, and life. About 80% is made of dark matter, whose mysterious nature is not yet known but may consist of some as-yet-undiscovered subatomic particles.

The team used a well-proven technique to determine the total amount of matter in the universe, which is to compare the observed number and mass of galaxy clusters per unit volume with predictions from numerical simulations.

The number of clusters observed at the present time, the so-called 'cluster abundance,' is very sensitive to cosmological conditions and, in particular, the total amount of matter. A higher percentage of the total matter in the universe would result in more clusters being formed. But it is difficult to measure the mass of any galaxy cluster accurately as most of the matter is dark, and we cannot see it directly with telescopes.

To overcome this difficulty, the team was forced to use an indirect tracer of cluster mass. They relied upon the fact that more massive clusters contain more galaxies than less massive clusters (mass richness relation: MRR). Because galaxies consist of luminous stars, the number of galaxies in each cluster can be utilized as a way of indirectly determining its total mass.

By measuring the number of galaxies in each cluster in their sample from the Sloan Digital Sky Survey, the team was able to estimate the total mass of each of the clusters. They were then able to compare the observed number and mass of galaxy clusters per unit volume against predictions from numerical simulations.

The best-fit match between observations and simulations was with a universe consisting of 31% of the total matter, a value that was in excellent agreement with that obtained using cosmic microwave background (CMB) observations from the Planck satellite. Notably, CMB is a completely independent technique.

They have succeeded in making the first measurement of matter density using the MRR, which is in excellent agreement with that obtained by the Planck team using the CMB method.

This work further demonstrates that cluster abundance is a competitive technique for constraining cosmological parameters and complementary to non-cluster techniques such as CMB anisotropies, baryon acoustic oscillations, Type Ia supernovae, or gravitational lensing.

 Mohamed H. Abdullah et al, Constraining Cosmological Parameters Using the Cluster Mass–Richness Relation, The Astrophysical Journal (2023). DOI: 10.3847/1538-4357/ace773

Comment by Dr. Krishna Kumari Challa on September 17, 2023 at 12:45pm

World falling dangerously short of climate goals: UN

A world facing catastrophic climate change is perilously off course in meeting goals for slashing carbon pollution and boosting finance for the developing world, according to the UN's first official progress report out Friday.

The 2015 Paris treaty has successfully driven climate action, but "much more is needed now on all fronts," said the report, which will underpin a crucial climate summit in Dubai at the end of the year.

"The world is not on track to meet the long-term goals of the Paris Agreement," including capping global warming at 1.5 degrees Celsius above mid-19th century levels, the report said.

Achieving net zero carbon emissions by 2050—another Paris goal—will also require phasing out the burning of all fossil fuels whose emissions cannot be captured or compensated.

The stocktake report also says that clean power must be dramatically ramped up, according to the first UN scorecard of the world's progress in meeting Paris Agreement climate goals.

"Scaling up renewable energy and phasing out all unabated fossil fuels are indispensable elements of just energy transitions to net zero emissions," it said.

"Unabated" refers to the absence of any technology that removes carbon emissions, either at the source or from the atmosphere.

Emissions have already peaked in developed and a few developing countries, but are continuing to rise in many of the world's largest economies.

The global stocktake report is a call for radical and immediate action to meet the goals of the Paris Agreement. 

The stocktake also highlights the need to rapidly and radically scale up financial support to developing nations so they can adapt to climate amplified weather disasters that are already eating away at their economies.

Source: News Agencies

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