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Comment by Dr. Krishna Kumari Challa on February 2, 2024 at 9:17am

Differences in heart rate variability in pregnant women could be marker for premature delivery

A team of obstetricians, gynecologists and data analysts has found evidence that wrist-based heart rate monitors could predict a premature birth.

In their study, reported on the open-access site PLOS ONE, pregnant volunteers wore WHOOP monitors prior to giving birth.

Previous research has shown that after becoming pregnant, women experience heart rate variability, defined as fluctuations in the amount of time between heartbeats. This variability declines as the pregnancy progresses, around 33 weeks. At that point, variability begins to increase steadily until birth.

For this new study, the research team wondered if the same changes in variability occur with women who experience premature deliveries. To find out, they turned to WHOOP, a maker of strap-on wrist sensors that monitor heart rate, noting that a small study conducted previously with researchers at WHOOP had shown that the device could be used to track heart rate variability in pregnant women.

In the new study, 241 pregnant women of various nationalities living in 15 countries agreed to wear the device in the months leading up to their delivery. The researchers found that heart rate variability for the women who delivered on or near their due date corresponded with previous findings—variability declined until approximately seven weeks before delivery. But things were markedly different for those women who delivered early—variability patterns were much less consistent. And variability also began a steady increase approximately seven weeks before delivery, which, in their cases, was well before their due dates.

The research team suggests that heart rate monitoring devices could become a new tool for use by obstetricians in monitoring their patients. Such devices, they note, may not only allow for better prediction of delivery dates, but could also help in employing therapies designed to prolong at-risk pregnancies.

Summer R. Jasinski et al, Wearable-derived maternal heart rate variability as a novel digital biomarker of preterm birth, PLOS ONE (2024). DOI: 10.1371/journal.pone.0295899

Comment by Dr. Krishna Kumari Challa on February 2, 2024 at 9:11am

ALMA spots the shadow of a molecular outflow from a quasar when the universe was less than 1 billion years old

Theoretical predictions have been confirmed with the discovery of an outflow of molecular gas from a quasar when the universe was less than a billion years old.

A quasar is a compact region powered by a supermassive black hole located in the center of a massive galaxy. They are extremely luminous, with a point-like appearance similar to stars, and are extremely distant from Earth. Owing to their distance and brightness, they provide a peek into conditions of the early universe, when it was less than 1 billion years old.

Researchers have discovered the first evidence of suppression of star formation driven by an outflow of molecular gas in a quasar-host galaxy in the early universe. Their findings, based on observations they made using the Atacama Large Millimeter/submillimeter Array (ALMA), in Chile, were published in The Astrophysical Journal.

Molecular gas is vital to the formation of stars. As the primary fuel of star formation, the ubiquity and high concentrations of molecular gas within a galaxy would lead to a vast number of stars being formed. By ejecting this gas into intergalactic space faster than it could be consumed by star formation, molecular outflows effectively suppress the formation of stars in galaxies that host quasars.

Theoretical work suggests that molecular gas outflows play an important role in the formation and evolution of galaxies from an early age, because they can regulate star formation. Quasars are especially energetic sources, so  scientists expected that they may be able to generate powerful outflows.

The quasar the researchers observed, J2054-0005, has a very high redshift—it and the Earth are apparently moving away from each other very fast.

The findings from this study are the first strong evidence that powerful molecular gas outflows from quasar-host galaxies exist and impact galaxy evolution at the early cosmic age.

Molecular outflow in the reionization-epoch quasar J2054-0005 revealed by OH 119 μm observations, The Astrophysical Journal (2024). DOI: 10.3847/1538-4357/ad0df5

Comment by Dr. Krishna Kumari Challa on February 1, 2024 at 2:48pm

What draws the moth to the flame

Nocturnal insects appear drawn to artificial lights because they instinctively twist their backs towards bright objects. The instinct to tilt their backs towards the brightest thing available at night — the sky — allows insects to quickly figure out which way is up. Researchers who tracked insects’ flight patterns with motion-capture cameras found that this even leads the animals to flip upside down and crash into the ground when the light source is underneath them. The researchers suggest reducing upward-facing lights and ground reflections to avoid confusing flying insects at night.

https://www.nature.com/articles/s41467-024-44785-3

Comment by Dr. Krishna Kumari Challa on February 1, 2024 at 2:39pm

 that's not what astronomers observe in today’s universe

(Below)

Part 2

Comment by Dr. Krishna Kumari Challa on February 1, 2024 at 2:38pm

Antimatter Mystery
Scientists are trying to figure out why there is more regular matter than antimatter in the universe. Antimatter is a mirror version of our normal array of particles, except with an opposite electrical charge. When the universe began at the big bang, equal amounts of matter and antimatter should have been created, but that's not what astronomers observe in today’s universe. In a new experiment, researchers searched for a minuscule property of electrons–the electric dipole moment (eEDM)--in hopes of finding evidence for extra particles or fields in the universe that could explain the antimatter mystery.

What they found: The physicists achieved the most precise measurement of the eEDM to date, and they found no evidence that this property exists for electrons. This means that if new fields explaining the matter-antimatter imbalance exist, their contribution to the eEDM may be indirect or occur at slightly higher energies than scientists thought. Future experiments could detect such fields and help physicists figure out the antimatter problem.

What the experts say: “We know there must be some reason out there for the universe of matter we live in to be the way it is—the question is how long it will take us to discover it,” writes Luke Caldwell, physicist at the University College London.
Part 1

Comment by Dr. Krishna Kumari Challa on February 1, 2024 at 2:36pm

undiagnosed

(Below)

Part 2 

Comment by Dr. Krishna Kumari Challa on February 1, 2024 at 2:35pm

Out of Rhythm
The occurrence of atrial fibrillation quadrupled over the past 50 years, according to recent studies. A-fib occurs when electrical signals in the upper chambers of the heart—the atria—misfire, causing an irregular heartbeat. People with the condition experience shortness of breath and tiredness. It can result in strokes if left untreated. But up to a quarter of cases go undiagnosed, according to recent research.

Cause and effect: Doctors are more on the lookout for the condition, which is partially responsible for the rising rates. Also people are living longer, and longer life comes with more health complications like heart disease and cancer. Last November leading medical groups issued new guidelines for preventing and treating A-fib, calling on doctors to encourage heart-healthy habits and early, more aggressive efforts to control heart rhythms.

 Some groups, including women and those in underserved communities, can go undiagnosed. “It's a disease that requires monitoring and detection,” says cardiologist Jared Magnani of the University of Pittsburgh. “And then it requires access to medical care, with a partner in making decisions about things like [medication], and finally more advanced therapies and treatment.”

Part 1

Comment by Dr. Krishna Kumari Challa on February 1, 2024 at 7:46am

Trees struggle to 'breathe' as climate warms, researchers find

Trees are struggling to sequester heat-trapping carbon dioxide (CO₂) in warmer, drier climates, meaning that they may no longer serve as a solution for offsetting humanity's carbon footprint as the planet continues to warm, according to a new study by researchers.

They  found that trees in warmer, drier climates are essentially coughing instead of breathing. They are sending CO₂ right back into the atmosphere far more than trees in cooler, wetter conditions.

Through the process of photosynthesis, trees remove CO₂ from the atmosphere to produce new growth. Yet, under stressful conditions, trees release CO₂ back to the atmosphere, a process called photorespiration. With an analysis of a global dataset of tree tissue, the research team demonstrated that the rate of photorespiration is up to two times higher in warmer climates, especially when water is limited.

They found the threshold for this response in subtropical climates begins to be crossed when average daytime temperatures exceed roughly 68 degrees Fahrenheit and worsens as temperatures rise further.

The results complicate a widespread belief about the role of plants in helping to draw down—or use—carbon from the atmosphere, providing new insight into how plants could adapt to climate change. Importantly, the researchers noted that as the climate warms, their findings demonstrate that plants could be less able to draw CO₂ out of the atmosphere and assimilate the carbon necessary to help the planet cool down.

Max K. Lloyd et al, Isotopic clumping in wood as a proxy for photorespiration in trees, Proceedings of the National Academy of Sciences (2023). DOI: 10.1073/pnas.2306736120

Comment by Dr. Krishna Kumari Challa on February 1, 2024 at 7:41am

Surgeons' choice of skin disinfectant impacts infection risk, Canadian-American study shows

Does the type of solution used by surgeons to disinfect skin before surgery impact the risk of surgical site infection? According to new research from an international trial jointly led by McMaster University and the University of Maryland School of Medicine—yes, it does!

Researchers of the PREPARE trial, which enrolled nearly 8,500 participants at 25 hospitals in Canada and the United States, found the use of iodine povacrylex in alcohol to disinfect a patient's skin could prevent surgical site infection in thousands of patients undergoing surgery for a closed fracture each year. The findings, published in The New England Journal of Medicine, are poised to have many hospitals consider a policy change to the use of iodine povacrylex in alcohol for fracture surgeries.

The trial included 6,785 patients undergoing surgery to treat a closed lower extremity or pelvic fracture and 1,700 patients undergoing surgery to treat an open fracture. Closed fractures occur when the bone is broken, but the skin is intact. Open fractures have an exceptionally high risk of infection due to the open wound and bone being exposed to environmental bacteria for hours before surgery. Researchers compared the two most commonly used antiseptic products in the United States and Canada. Patients with closed fractures randomized to receive 0.7% iodine povacrylex in 74% isopropyl alcohol for skin antisepsis experienced fewer post-operative surgical site infections than those randomized to receive 2% chlorhexidine gluconate in 70% isopropyl alcohol. In patients with open fractures, the risk of infection was similar between the two different antiseptic skin preparation solutions.

These results suggest that the use of iodine povacrylex in alcohol as preoperative skin antisepsis could prevent surgical-site infection in thousands of patients with closed fractures each year.

Skin Antisepsis before Surgical Fixation of Extremity Fractures, New England Journal of Medicine (2024). DOI: 10.1056/NEJMoa2307679

Comment by Dr. Krishna Kumari Challa on February 1, 2024 at 7:37am

Study finds 1 in 10 veterans diagnosed with dementia may instead have cognitive decline from cirrhosis

As many as 10% of older U.S. veterans diagnosed with dementia may suffer instead from reversible cognitive decline caused by advanced liver disease, according to an analysis from the Virginia Commonwealth University's School of Medicine and the Richmond VA Medical Center.

It can be difficult for physicians to differentiate dementia from the cognitive decline caused by cirrhosis, called hepatic encephalopathy. If undetected, patients may not receive appropriate treatment that can reverse or halt the impairment. The study, published in the journal JAMA Network Open, sought to learn more about the prevalence and risk factors of undiagnosed cirrhosis and potential encephalopathy in veterans with dementia. The findings suggest that physicians treating veterans with dementia, even without a cirrhosis diagnosis, should consider assessing their patients for liver disease. Identifying cirrhosis early on may unveil reversible causes of cognitive impairment, potentially improving the lives of these patients.

Hepatic encephalopathy is a nervous system disorder brought on by cirrhosis, an advanced form of liver disease in which patients experience severe scarring of the liver. When the liver doesn't work properly, toxins build up in the blood. These toxins can travel to the brain and affect brain function, leaving patients confused or delirious. Widely available medications can readily rid the body of toxins and reverse this condition, but without treatment, patients can lapse into coma or die.

Undiagnosed Cirrhosis and Hepatic Encephalopathy in a National Cohort of Veterans With Dementia, JAMA Network Open (2024). DOI: 10.1001/jamanetworkopen.2023.53965

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