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Comment by Dr. Krishna Kumari Challa on November 22, 2023 at 11:06am

Unearthing how a carnivorous fungus traps and digests worms

A new analysis sheds light on the molecular processes involved when a carnivorous species of fungus known as Arthrobotrys oligospora senses, traps and consumes a worm. 

A. oligospora usually derives its nutrients from decaying organic matter, but starvation and the presence of nearby worms can prompt it to form traps to capture and consume worms. A. oligospora is just one of many species of fungi that can trap and eat very small animals.

When A. oligospora first senses a worm, the findings suggest, DNA replication and the production of ribosomes (structures that build proteins in a cell) both increase. Next, the activity increases of many genes that encode proteins that appear to assist in the formation and function of traps, such as secreted worm-adhesive proteins and a newly identified family of proteins dubbed "trap enriched proteins" (TEP).

Finally, after A. oligospora has extended filamentous structures known as hyphae into a worm to digest it, the activity is boosted by genes coding for a variety of enzymes known as proteases—in particular, a group known as metalloproteases. Proteases break down other proteins, so these findings suggest that A. oligospora uses proteases to aid in worm digestion.

These findings could serve as a foundation for future research into the molecular mechanisms involved in A. oligospora predation and other fungal predator-prey interactions.

Lin H-C, de Ulzurrun GV-D, Chen S-A, Yang C-T, Tay RJ, Iizuka T, et al. (2023) Key processes required for the different stages of fungal carnivory by a nematode-trapping fungus. PLoS Biology (2023). DOI: 10.1371/journal.pbio.3002400

Comment by Dr. Krishna Kumari Challa on November 22, 2023 at 11:00am

Babies as young as four months show signs of self-awareness: Study

Babies as young as four months old can make sense of how their bodies interact with the space around them, according to new research.

The findings, published in Scientific Reports, shed new light on how self-awareness develops. Experts  showed babies a ball on a screen moving towards or away from them. When the ball was closest to them on the screen, the babies were presented with a 'touch' (a small vibration) on their hands while their brain activity was being measured.  The researchers found that from just four months old, babies show enhanced somatosensory (tactile) brain activity when a touch is preceded by an object moving toward them.

These findings indicate that even in the first few months of life, before babies have even learned to reach for objects, the multisensory brain is wired up to make links between what babies see and what they feel. This means they can sense the space around them and understand how their bodies interact with that space. This is sometimes referred to as peripersonal space.

Of course, humans do this all the time as adults, using our combined senses to perceive where we are in space and making predictions about when we will touch an object or not. But now that we know that babies in the early stages of their development begin to show signs of this, it opens up questions about how much of these abilities are learned or innate.

Visual objects approaching the body modulate subsequent somatosensory processing at 4 months of age, Scientific Reports (2023). DOI: 10.1038/s41598-023-45897-4

Comment by Dr. Krishna Kumari Challa on November 22, 2023 at 10:55am

High temperatures may have caused over 70,000 excess deaths in Europe in 2022

The burden of heat-related mortality during the summer of 2022 in Europe may have exceeded 70,000 deaths according to a study .

The authors of the study, published in The Lancet Regional Health—Europe, revised upwards initial estimates of the mortality associated with record temperatures in 2022 on the European continent. The study is titled "The effect of temporal data aggregation to assess the impact of changing temperatures in Europe: an epidemiological modelling study."

Ballester J et al, The effect of temporal data aggregation to assess the impact of changing temperatures in Europe: an epidemiological modelling study, The Lancet Regional Health—Europe (2023). DOI: 10.1016/j.lanepe.2023.100779

Comment by Dr. Krishna Kumari Challa on November 22, 2023 at 10:50am

A wearable robot that assists people with walking

In recent years, roboticists have introduced increasingly advanced systems, which could open exciting new possibilities for surgery, rehabilitation, and health care assistance. These robotic systems are already helping to improve the quality of life of many people with disabilities, as well as patients who suffered physical

trauma or underwent medical procedures.

Researchers recently introduced a new wearable robot designed to specifically assist humans who have difficulties walking due to aging, muscle weakness, surgeries or specific medical conditions. This robot, presented in a paper published in Science Robotics, was found to improve balance, while also reducing the energy spent while walking (the so-called metabolic cost). 

In contrast with other robotic systems for hip abduction assistance proposed in the past, the robot now created  focuses on the frontal plane. This is the frontal part of the human body, known to support movements and lateral stability while walking.

Juneil Park et al, Effect of hip abduction assistance on metabolic cost and balance during human walking. Science Robotics (2023). DOI: 10.1126/scirobotics.ade0876.

Comment by Dr. Krishna Kumari Challa on November 21, 2023 at 1:57pm

AWEsome Waves in Earth’s Airglow

Comment by Dr. Krishna Kumari Challa on November 21, 2023 at 12:31pm

What is a sonar pulse and how can it injure humans under water?
Light doesn't travel well underwater—even in clear waters, you can see perhaps some tens of meters. Sound, however, travels very well and far underwater. This is because water is much denser than air, and so can respond faster and better to acoustic pressure waves—sound waves.

Because of these properties, ships use sonar to navigate through the ocean and to "see" underwater. The word "sonar" stands for sound navigation and ranging.

Sonar equipment sends out short acoustic (sound) pulses or pings and then analyzes the echoes. Depending on the timing, amplitude, phase, and direction of the echoes the equipment receives, you can tell what's underwater—the seafloor, canyon walls, coral, fishes, and of course, ships and submarines.

Most vessels—from small, private boats to large commercial tankers—use sonar. However, compared to your off-the-shelf sonar used for finding fish, navy sonars are stronger.
The effects of sonar on divers
We don't hear well underwater—no surprise since we've evolved to live on land. Having said that, you would hear a sonar sound underwater (a mid-to-high pitch noise) and would know you've been exposed.
When it comes to naval sonars, human divers have rated the sound as "unpleasant to severe" at levels of roughly 150dB re 1 µPa (decibel relative to a reference pressure of one micro pascal, the standard reference for underwater sound). This would be, perhaps, very roughly 10km away from a military sonar. Note that we can't compare sound exposure under water to what we'd receive through the air because there are too many physical differences between the two.

Human tolerance limits are roughly 180dB re one µPa, which would be around 500m from military sonar. At such levels, humans might experience dizziness, disorientation, temporary memory and concentration impacts, or temporary hearing loss.
At higher received levels, closer ranges, or longer exposures, you might see more severe physiological or health impacts. In extreme cases, in particular, for impulsive, sudden sound (which sonar is not), sound can cause damage to tissues and organs.
What does sonar do to marine animals?
Some of the information on what noise might do to humans underwater comes from studies and observations of animals.

While they typically don't have outer ears (except for sea lions), marine mammals have inner ears that function similarly to ours. They can receive hearing damage from noise, just like we do. This might be temporary, like the ringing ears or reduced sensitivity you might experience after a loud concert, or it can be permanent.

Marine mammals living in a dark ocean rely on sound and hearing to a greater extent than your average human. They use sound to navigate, hunt, communicate with each other and to find mates. Toothed whales and dolphins have evolved a biological echo sounder or biosonar, which sends out series of clicks and listens for echoes. So, interfering with their sounds or impacting their hearing can disrupt critical behaviors.

Finally, sound may also impact non-mammalian fauna, such as fishes, which rely on acoustics rather than vision for many of their life functions.

https://theconversation.com/what-is-a-sonar-pulse-and-how-can-it-in...

Comment by Dr. Krishna Kumari Challa on November 21, 2023 at 12:06pm

World's richest 1% emit as much carbon as bottom two-thirds: report

The richest one percent of the global population are responsible for the same amount of carbon emissions as the world's poorest two-thirds, or five billion people, according to an analysis published Sunday by the nonprofit Oxfam International.

While fighting the climate crisis is a shared challenge, not everyone is equally responsible and government policies must be tailored accordingly, according to the report.

It says, the richer you are, the easier it is to cut both your personal and your investment emissions. You don't need that third car, or that fourth holiday, or you don't need to be invested in the cement industry." 

Climate Equality: A Planet for the 99%", was based on research compiled by the Stockholm Environment Institute (SEI) and it examined the consumption emissions associated with different income groups up to the year 2019.
Among the key findings of this study are that the richest one percent globally—77 million people—were responsible for 16 percent of global emissions related to their consumption.

That is the same share as the bottom 66 percent of the global population by income, or 5.11 billion people.
Source: 2023 AFP

Comment by Dr. Krishna Kumari Challa on November 21, 2023 at 11:17am

Levels of this flavanol can vary dramatically in red wine

Quercetin is produced by the grapes in response to sunlight. If you grow grapes with the clusters exposed, such as they do in the Napa Valley for their cabernets, you get much higher levels of quercetin. In some cases, it can be four to five times higher.

Levels of quercetin can also differ depending on how the wine is made, including skin contact during fermentation, fining processes and aging.

Scientists are testing this hypothesis  now .

 Inhibition of ALDH2 by Quercetin Glucuronide Suggests a New Hypothesis to Explain Red Wine Headaches, Scientific Reports (2023).

Part 2

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Comment by Dr. Krishna Kumari Challa on November 21, 2023 at 11:12am

Why does even a small amount of red wine give some people headaches?

 For some people, drinking red wine even in small amounts causes a headache. Typically, a "red wine headache" can occur within 30 minutes to three hours after drinking as little as a small glass of wine.

In a new study, scientists examined why this happens—even to people who don't get headaches when drinking small amounts of other alcoholic beverages. Researchers think that a flavanol found naturally in red wines can interfere with the proper metabolism of alcohol and can lead to a headache. The study was published in the journal Scientific Reports.

This flavanol is called quercetin and it is naturally present in all kinds of fruits and vegetables, including grapes. It's considered a healthy antioxidant and is even available in supplement form. But when metabolized with alcohol, it can be problematic.

When it gets in your bloodstream, your body converts it to a different form called quercetin glucuronide. In that form, it blocks the metabolism of alcohol. As a result, people can end up accumulating the toxin acetaldehyde. Acetaldehyde is a well-known toxin, irritant and inflammatory substance. Researchers know that high levels of acetaldehyde can cause facial flushing, headache and nausea.

The medication disulfiram prescribed to alcoholics to prevent them from drinking causes these same symptoms. That's because the drug also causes the toxin to build up in the body when normally an enzyme in the body would break it down. About 40% of the East Asian population also has an enzyme that doesn't work very well, allowing acetaldehyde to build up in their system.

 When susceptible people consume wine with even modest amounts of quercetin, they develop headaches, particularly if they have a preexisting migraine or another primary headache condition.

Part 1

Comment by Dr. Krishna Kumari Challa on November 20, 2023 at 11:13am

Brightest flash ever disturbed Earth's atmosphere last year

Last year the brightest flash of light ever seen in the night sky disturbed Earth's upper atmosphere in a way that has never before detected before.

A massive burst of gamma rays from an enormous cosmic explosion around two billion light years away arrived at Earth on October 9, 2022, lighting up telescopes around the world.

Quickly nicknamed the "BOAT"—for Brightest Of All Time—the flash lasted just seven minutes but its afterglow was visible to amateur astronomers for seven hours.

The flash activated lightning detectors in India and triggered instruments that normally study explosions on the sun called solar flares. It also affected long wave radio communications in the lower ionosphere, a section of Earth's upper atmosphere around 60 to 350 kilometers (37 to 217 miles) above the surface. The BOAT also affected the upper ionosphere—the very first time a gamma-ray burst has been observed in this section of the atmosphere.

From 350 to 950 kilometers above Earth, near the edge of the space, the upper ionosphere is where radiation from the sun turns into charged particles that form an important electric field.

Researchers found a shape in the electric field that had never been observed before.

The research would help scientists understand the potential threat that other gamma-ray bursts could pose in the future. The worst-case scenario would be if such a powerful blast came from much closer to home—say, within our own Milky Way galaxy. That could "completely erase" Earth's ozone layer.

This would expose everything on the surface to the full might of the sun's ultraviolet radiation, potentially wiping out life on Earth. There has previously been speculation that past gamma-ray bursts could have caused ancient mass extinction events.

But It is also possible that the ionosphere would absorb all the gamma rays and "nothing would happen" to those of us on the ground.

The blast came from the direction of the constellation Sagitta and traveled an estimated 1.9 billion years to reach Earth. It is now 2.4 billion light years away because of the expansion of the universe. On average, more than one gamma-ray-burst reaches Earth every day. But one with the brightness of the BOAT is estimated to come around once every 10,000 years.

Mirko Piersanti, Evidence of an upper ionospheric electric field perturbation correlated with a gamma ray burst, Nature Communications (2023). DOI: 10.1038/s41467-023-42551-5. www.nature.com/articles/s41467-023-42551-5

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