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Comment by Dr. Krishna Kumari Challa on July 17, 2024 at 10:14am

Researchers found that where apparel was sold is not necessarily where plastic waste leaks into the environment. For apparel originally sold in high-income countries like the United States, Japan and many others, most of the resulting pollution happened in lower-income countries where these pieces of clothing might be sold in the secondary market.

This finding points to a major concern with how people in higher-income countries consume apparel.

Anna Kounina et al, The global apparel industry is a significant yet overlooked source of plastic leakage, Nature Communications (2024). DOI: 10.1038/s41467-024-49441-4

Part 2

Comment by Dr. Krishna Kumari Challa on July 17, 2024 at 10:13am

Apparel industry leaks millions of tons of plastic into environment each year, study finds

A study has found that waste from the global apparel industry is leaking millions of tons of plastic into the environment each year—an overlooked pollution source which may be getting worse over time.

The findings are detailed in a recent study by researchers, which found that global apparel consumption resulted in over 20 million tons of plastic waste in 2019. Around 40% of that waste may have been improperly managed and become environmental pollution, a process known as "plastic leakage."

Textile waste was divided between two sources; clothing made from synthetic materials like polyester, nylon and acrylic, and clothing made from cotton and other natural fibers. Researchers looked at plastic waste generated across an apparel product's "value chain," which refers to the entire lifecycle of a product—including, for example, not only the piece of apparel itself, but the plastics used to wrap it.

Much of the plastic waste that leaks into the environment comes from clothes that are thrown away, especially synthetic apparel. There is also waste from manufacturing, packaging and even from tire abrasion during transport, as well as microplastics which get pulled into the water when we wash our clothes.

Researchers found that synthetic apparel was by far the largest source of plastic waste. 

As opposed to the end-of-life plastic waste created by discarded synthetic apparel, plastic waste from cotton and other fibers came almost entirely from the plastic used in packaging.

Part 1

Comment by Dr. Krishna Kumari Challa on July 17, 2024 at 9:46am

New study finds early detection of miRNAs in maternal blood may offer potential for predicting preeclampsia

Preeclampsia is a complication of pregnancy. With preeclampsia,  a woman might have high blood pressure, high levels of protein in urine that indicate kidney damage (proteinuria), or other signs of organ damage.

Pre-eclampsia is thought to be caused by the placenta not developing properly due to a problem with the blood vessels supplying it.

Without treatment, preeclampsia can cause serious health problems for the pregnant woman and her baby, and can even cause seizures or death. Health problems for pregnant people who have preeclampsia include: Kidney, liver and brain damage. Problems with how their blood clots.

Preeclampsia (PE) is a significant contributor to the increase in maternal morbidity and mortality worldwide. It can also  result in premature birth with associated morbidities for the infants as well.

A new study by researchers  finds that early detection of specific microRNAs (miRNAs) packaged in vesicles may offer the opportunity to predict preeclampsia in pregnant people before clinical symptoms manifest.

The study identifies the potential of a specific set of miRNAs within extracellular vesicles (EVs)—tiny particles that transfer information between cells—as a noninvasive biomarker for preeclampsia.

Compared to women with healthy pregnancies, women with preeclampsia had miRNAs found within EVs in early pregnancy. Researchers identified 148 miRNAs with differential abundance in preeclampsia EVs: 12 in higher amounts and 135 in lower amounts compared to EVs from healthy pregnancies. Specific groups of miRNAs showed clear differences in how many were present in EVs from women with preeclampsia.

The EVs taken from the blood of pregnant women with preeclampsia contained a group of microRNAs starting as early as the first to the second trimester of pregnancy. These miRNAs follow a specific pattern throughout pregnancy that changes when preeclampsia develops. Some miRNAs originate from the placenta and act as messengers between the placenta and other organs in the body.

The researchers say this panel of miRNAs has the potential to predict the development of symptoms of preeclampsia, especially late-onset preeclampsia.

The findings suggest a future in which miRNAs within EVs could transform the current monitoring and care of mothers everywhere. They would serve as noninvasive biomarkers for early detection of preeclampsia in pregnancy and significantly enhance the understanding of the condition's pathophysiology.

Circulating Extracellular Vesicular MicroRNA Signatures in Early Gestation Show an Association with Subsequent Clinical Features of Pre-Eclampsia, Scientific Reports (2024). DOI: 10.1038/s41598-024-64057-w

Comment by Dr. Krishna Kumari Challa on July 17, 2024 at 8:50am

During meiosis, chromosomes break apart and recombine, resulting in new combinations of gene copies. After these so-called crossover events occur, chromosomes are randomly shuffled through cell divisions.

In parthenogenetic reproduction, a clonal line draws from two identical chromosomal sets, so you expect to lose a lot of diversity during each cycle.

To understand how this may not be true for clonal raider ants, the researchers focused on mother-daughter and sister-sister pairs of ants. To make sure they had true family duos, they tracked transgenic ants that fluoresce red when viewed through a microscope—a breakthrough method of genetic manipulation developed in Kronauer's lab by researcher Taylor Hart. These pairs were the only animals in their colonies to glow.

Using linked-read genetic sequencing—which allows the reconstruction of whole chromosome sequences—they found that no genetic diversity was lost from mother to daughter. However, the daughter's genomes showed evidence of crossovers. In all, they documented 144 crossover events, and only one showed a loss of genetic diversity.

That's because the chromosomes that have recombined with each other are always inherited together. This co-inheritance could explain how this species continues to survive. In clonal raider ants, it's 800% more likely to occur than would be expected from a random roll of the genetic dice.

This strategy for retaining genetic diversity has never been documented before. Its existence suggests there may be more ways to get around random genetic inheritance than we knew. One well-known deviation from random inheritance, for example, is when "selfish" genes promote their own propagation over other genes, essentially rigging the game in their favor.

But this deviation can't account for clonal raider ant reproduction, which is "unselfish" because no gene has an advantage; all gene copies are co-inherited. Whether this strategy of unselfish inheritance occurs in other animals—including sexually reproducing species—is unknown.

This finding highlights the usefulness of studying species with unusual reproductive biology.

Kip D. Lacy et al, Co-inheritance of recombined chromatids maintains heterozygosity in a parthenogenetic ant, Nature Ecology & Evolution (2024). DOI: 10.1038/s41559-024-02455-z

Part 2

Comment by Dr. Krishna Kumari Challa on July 17, 2024 at 8:43am

Asexual reproduction usually leads to a lack of genetic diversity. Not for these ants

Genetic diversity is essential to the survival of a species. It's easy enough to maintain if a species reproduces sexually; an egg and a sperm combine genetic material from two creatures into one, forming a genomically robust offspring with two distinct versions of the species' genome.

Without that combination of different genetic makeups, asexually reproducing species typically suffer from a lack of diversity that can doom them to a limited run on Earth. One such animal should be the clonal raider ant, which produces daughter after genetically identical daughter directly from an unfertilized ovum through parthenogenesis, a method of asexual reproduction in which the offspring inherits two sets of genetically identical chromosomes from its mother.

Over time, the random inheritance of these chromosomes on endless repeat should lead to catastrophic loss of genetic distinctiveness and eventual species collapse. And yet this blind, queenless insect—a native of Bangladesh that is now found in tropical settings around the world—seems to be surviving just fine. How is that possible?

As researchers at Rockefeller University recently discovered, the clonal raider ant doesn't gamble when it comes to passing along its genes. Instead, it ensures that offspring inherit two distinct versions of its entire genome, largely preserving the genetic diversity present in the ancient founder of each clonal line.

In theory, this shouldn't work: Chromosomes are thought to randomly shuffle during meiosis, the type of cell division used to produce sperm and egg cells during reproduction in all animals, plants, and fungi. Yet in this animal, the process seems to be anything but random, as they reported in Nature Ecology & Evolution.

Yes, clonal raider ants are avoiding the loss of genetic diversity that otherwise routinely results from parthenogenesis. Maybe this diversity enables the survival of the species.

Part 1

Comment by Dr. Krishna Kumari Challa on July 16, 2024 at 10:18am

CAR-T could shrink kids’ brain tumours
CAR-T therapy, which genetically engineers a person’s own immune cells to destroy tumour cells, could treat deadly brain and spinal cancers in children. In small clinical trials, the therapy shrank tumours by more than half in some cases and only one participant experienced severe side effects. One young man even remained in remission more than 30 months after his first treatment.

https://www.nature.com/articles/d41586-024-02255-2?utm_source=Live+...

Comment by Dr. Krishna Kumari Challa on July 16, 2024 at 8:54am

Existence of lunar lava tube cave demonstrated

The presence of conduits below the lunar surface has been theorized and extensively debated for at least 50 years. Now, an analysis of NASA Lunar Reconnaissance Orbiter radar data reveals what lies below the Mare Tranquillitatis.

For the first time, scientists have demonstrated the existence of a tunnel in the lunar subsurface. It seems to be an empty lava tube. The study, published in Nature Astronomy, is the result of an international collaboration.

Cosmic and solar radiation can be as much as 150 times more powerful on the lunar surface than we experience on Earth and there is a constant threat of meteorite impact. These conditions drive a need to find safe sites for the construction of infrastructure that can support sustained exploration. Caves such as this one offer a solution to that problem.

Leonardo Carrer, Radar evidence of an accessible cave conduit on the Moon below the Mare Tranquillitatis pit, Nature Astronomy (2024). DOI: 10.1038/s41550-024-02302-y. www.nature.com/articles/s41550-024-02302-y

Comment by Dr. Krishna Kumari Challa on July 16, 2024 at 8:49am

If water temperatures rise, the solubility of oxygen in the water decreases. In addition, global warming enhances stratification of the water column, because warmer, low-salinity water with a lower density lies on top of the colder, saltier deep water below.

This hinders the exchange of the oxygen-poor deep layers with the oxygen-rich surface water. In addition, nutrient inputs from land support algal blooms, which lead to more oxygen being consumed as more organic material sinks and is decomposed by microbes at depth.
Areas in the sea where there is so little oxygen that fish, mussels or crustaceans can no longer survive threaten not only the organisms themselves, but also ecosystem services such as fisheries, aquaculture, tourism and cultural practices.

Microbiotic processes in oxygen-depleted regions also increasingly produce potent greenhouse gases such as nitrous oxide and methane, which can lead to a further increase in global warming and thus a major cause of oxygen depletion.
The authors warn: We are approaching critical thresholds of aquatic deoxygenation that will ultimately affect several other planetary boundaries.
Failure to address aquatic deoxygenation will, ultimately, not only affect ecosystems but also economic activity, and society at a global level.

 Kevin C. Rose et al, Aquatic deoxygenation as a planetary boundary and key regulator of Earth system stability, Nature Ecology & Evolution (2024). DOI: 10.1038/s41559-024-02448-y

Part 2

Comment by Dr. Krishna Kumari Challa on July 16, 2024 at 8:48am

Loss of oxygen in bodies of water identified as new tipping point

Oxygen concentrations in our planet's waters are decreasing rapidly and dramatically—from ponds to the ocean. The progressive loss of oxygen threatens not only ecosystems, but also the livelihoods of large sectors of society and the entire planet, according to the authors of an international study involving GEOMAR published recently in Nature Ecology & Evolution.

Oxygen is a fundamental requirement of life on planet Earth. The loss of oxygen in water, also referred to as aquatic deoxygenation, is a threat to life at all levels. The international team of researchers describes how ongoing deoxygenation presents a major threat to the livelihoods of large parts of society and for the stability of life on our planet.

Previous research has identified a suite of global scale processes, referred to as planetary boundaries, that regulate the overall habitability and stability of the planet. If critical thresholds in these processes are passed, the risk of large-scale, abrupt or irreversible environmental changes ("tipping points") increases and the resilience of our planet, its stability, is jeopardized.

Among the nine planetary boundaries are climate change, land use change, and biodiversity loss. The authors of the new study argue that aquatic deoxygenation both responds to, and regulates, other planetary boundary processes.

Across all aquatic ecosystems, from streams and rivers, lakes, reservoirs, and ponds to estuaries, coasts, and the open ocean, dissolved oxygen concentrations have rapidly and substantially declined in recent decades.

Lakes and reservoirs have experienced oxygen losses of 5.5% and 18.6% respectively since 1980. The ocean has experienced oxygen losses of around 2% since 1960. Although this number sounds small, due to the large ocean volume it represents an extensive mass of oxygen lost.

Marine ecosystems have also experienced substantial variability in oxygen depletion.

The volumes of aquatic ecosystems affected by oxygen depletion have increased dramatically across all types.

The causes of aquatic oxygen loss are global warming due to greenhouse gas emissions and the input of nutrients as a result of land use.

Part 1

Comment by Dr. Krishna Kumari Challa on July 16, 2024 at 7:13am

Study finds abortion restrictions harm mental health, with low-income women hardest hit

People living in states that enacted tighter abortion restrictions in the wake of the Dobbs v. Jackson Women's Health decision, which returned regulation of abortion access to state legislatures, are more likely to report elevated levels of mental distress. This is particularly true for people of lower socioeconomic means.

These are the key takeaways of July 2024 paper published in Science Advances.

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