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Comment by Dr. Krishna Kumari Challa on November 30, 2023 at 11:12am

Scientists discover rare six-planet system that moves in strange synchrony

Scientists have discovered a rare sight in a nearby star system: Six planets orbiting their central star in a rhythmic beat. The planets move in an orbital waltz that repeats itself so precisely that it can be readily set to music.

A rare case of an "in sync" gravitational lockstep, the system could offer deep insight into planet formationand evolution.

The analysis, led by UChicago scientist Rafael Luque, was published Nov. 29 in Nature.

The six planets orbit a star known as HD110067, which lies around 100 light-years away in the northern constellation of Coma Berenices.

In 2020, NASA's Transiting Exoplanet Survey Satellite (TESS) detected dips in the star's brightness that indicated planets were passing in front of the star's surface. Combining data from both TESS and the European Space Agency's CHaracterizing ExOPlanet Satellite (Cheops), a team of researchers analyzed the data and discovered a first-of-its-kind configuration.

While multi-planet systems are common in our galaxy, those in a tight gravitational formation known as "resonance" are observed by astronomers far less often.

In this case, the planet closest to the star makes three orbits for every two of the next planet out—called a 3/2 resonance—a pattern that is repeated among the four closest planets. Among the outermost planets, a pattern of four orbits for every three of the next planet out (a 4/3 resonance) is repeated twice.

And these resonant orbits are rock-solid: The planets likely have been performing this same rhythmic dance since the system formed billions of years ago, the scientists said.

Orbitally resonant systems are extremely important to find because they tell astronomers about the formation and subsequent evolution of the planetary system. Planets around stars tend to form in resonance but can be easily perturbed. For example, a very massive planet, a close encounter with a passing star, or a giant impact event can all disrupt the careful balance.

As a result, many of the multi-planet systems known to astronomers are not in resonance but look close enough that they could have been resonant once. However, multi-planet systems preserving their resonance are rare.

Rafael Luque, A resonant sextuplet of sub-Neptunes transiting the bright star HD 110067, Nature (2023). DOI: 10.1038/s41586-023-06692-3. www.nature.com/articles/s41586-023-06692-3

Comment by Dr. Krishna Kumari Challa on November 29, 2023 at 12:48pm

Meta AI develops a non-invasive method to decode speech from brain activity

Recent technological advancements have opened invaluable opportunities for assisting people who are experiencing impairments or disabilities. For instance, they have enabled the creation of tools to support physical rehabilitation, to practice social skills, and to provide daily assistance with specific tasks.

Recent technological advancements have opened invaluable opportunities for assisting people who are experiencing impairments or disabilities. For instance, they have enabled the creation of tools to support physical rehabilitation, to practice social skills, and to provide daily assistance with specific tasks. Researchers at Meta AI recently developed a promising and non-invasive method to decode speech from a person's brain activity, which could allow people who are unable to speak to relay their thoughts via a computer interface. Their proposed method, presented in Nature Machine Intelligence, merges the use of an imaging technique and machine learning.

Alexandre Défossez et al, Decoding speech perception from non-invasive brain recordings, Nature Machine Intelligence (2023). DOI: 10.1038/s42256-023-00714-5.

Comment by Dr. Krishna Kumari Challa on November 28, 2023 at 12:22pm

How to make waves eat themselves
Physicists have demonstrated that two cavities carved into the side of a channel can totally dissipate the energy of incoming waves. In a model set-up with real water, researchers were able to achieve ‘perfect absorption’ — in which the waves completely cancelled themselves out as they bounced off the cavity walls — with waves of a frequency of 2.9 Hertz. The finding hints at the possibility of designing structures to protect coastlines or harvest wave energy.

https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.131.204002

Comment by Dr. Krishna Kumari Challa on November 28, 2023 at 12:21pm

Chocolate discharges the same chemical in your body as when you feel love.
Chocolate raises levels of phenylethylamine (PEA), “the love chemical”. This chemical gets our hearts pumping, increases blood pressure, heart, and respiratory rates, and increases feelings of joy
Chocolate releases this neurochemical of pleasure in our brains. Dopamine kick starts a brain messenger chemical called DARP-32 that activates hormones. This is the chemical that surges through us when we are embraced by someone we love.
Chocolate contains tryptophan, a precursor to serotonin. Serotonin is our other feel good chemical. It diminishes anxiety and increases our ability to fight stress. Many antidepressants work by increasing serotonin levels.
So those who are not in love go eat chocolates and be happy.

Comment by Dr. Krishna Kumari Challa on November 28, 2023 at 10:41am

Worrying about the present and future of our warming planet has also provoked rising anxiety, depression and even post-traumatic stress—particularly for people already struggling with these disorders, psychologists have warned.

In the first 10 months of the year, people searched online for the term "climate anxiety" 27 times more than during the same period in 2017, according to data from Google Trends cited by the BBC this week.

Source: 

The Lancet and AFP

Part 4

Comment by Dr. Krishna Kumari Challa on November 28, 2023 at 10:40am

Almost 99 percent of the world's population breathes air that exceeds the WHO's guidelines for air pollution.

Outdoor air pollution driven by fossil fuel emissions kills more than four million people every year, according to the WHO.

It increases the risk of respiratory diseases, strokes, heart disease, lung cancer, diabetes and other health problems, posing a threat that has been compared to tobacco.

The damage is caused partly by PM2.5 microparticles, which are mostly from fossil fuels. People breathe these tiny particles into their lungs, where they can then enter the bloodstream.

While spikes in air pollution, such as extremes seen in India's capital New Delhi earlier this month, trigger respiratory problems and allergies, long-term exposure is believed to be even more harmful.

The changing climate means that mosquitoes, birds and mammals will roam beyond their previous habitats, raising the threat that they could spread infectious diseases with them.

Mosquito-borne diseases that pose a greater risk of spreading due to climate change include dengue, chikungunya, Zika, West Nile virus and malaria.

The transmission potential for dengue alone will increase by 36 percent with 2°C warming, The Lancet Countdown report warned.

Storms and floods create stagnant water that are breeding grounds for mosquitoes, and also increase the risk of water-borne diseases such as cholera, typhoid and diarrhea.

Scientists also fear that mammals straying into new areas could share diseases with each other, potentially creating new viruses that could then jump over to humans.

Part 3

Comment by Dr. Krishna Kumari Challa on November 28, 2023 at 10:38am

Heat is believed to have caused more than 70,000 deaths in Europe during summer last year, researchers said this week, revising the previous number up from 62,000.

Worldwide, people were exposed to an average of 86 days of life-threatening temperatures last year, according to The Lancet Countdown report earlier this week.

The number of people over 65 who died from heat rose by 85 percent from 1991-2000 to 2013-2022, it added.

And by 2050, more than five times more people will die from the heat each year under a 2°C warming scenario, The Lancet Countdown projected.

More droughts will also drive rising hunger. Under the scenario of 2°C warming by the end of the century, 520 million more people will experience moderate or severe food insecurity by 2050.

Meanwhile, other extreme weather events such as storms, floods and fires will continue to threaten the health of people across the world.

Part 2

Comment by Dr. Krishna Kumari Challa on November 28, 2023 at 10:38am

How climate change impacts health

Extreme heat, air pollution and the increasing spread of deadly infectious diseases are just some of the reasons why the World Health Organization has called climate change the single biggest health threat facing humanity.

Global warming must be limited to the Paris Agreement target of 1.5 degrees Celsius "to avert catastrophic health impacts and prevent millions of climate change-related deaths", according to the WHO.

However, under current national carbon-cutting plans, the world is on track to warm up to 2.9°C this century, the UN said this week.

While no one will be completely safe from the effects of climate change, experts expect that most at risk will be children, women, the elderly, migrants and people in less developed countries which have emitted the least planet-warming greenhouse gases.

This year is widely expected to be the hottest on record. And as the world continues to warm, even more frequent and intense heat waves are expected to follow.

Part 1

Comment by Dr. Krishna Kumari Challa on November 28, 2023 at 10:26am

Not just meteorite: New clues about the demise of dinosaurs

What wiped out the dinosaurs? A meteorite plummeting to Earth is only part of the story, a new study suggests. Climate change triggered by massive volcanic eruptions may have ultimately set the stage for the dinosaur extinction, challenging the traditional narrative that a meteorite alone delivered the final blow to the ancient giants.

Researchers delved into volcanic eruptions of the Deccan Traps—a vast and rugged plateau in Western India formed by molten lava. Erupting a staggering 1 million cubic kilometers of rock, it may have played a key role in cooling the global climate around 65 million years ago. The work took researchers around the world, from hammering out rocks in the Deccan Traps to analyzing the samples in England and Sweden. 

In the lab, the scientists estimated how much sulfur and fluorine was injected into the atmosphere by massive volcanic eruptions in the 200,000 years before the dinosaur extinction.

Remarkably, they found the sulfur release could have triggered a global drop in temperature around the world—a phenomenon known as a volcanic winter.

The research demonstrates that climatic conditions were almost certainly unstable, with repeated volcanic winters that could have lasted decades, prior to the extinction of the dinosaurs. This instability would have made life difficult for all plants and animals and set the stage for the dinosaur extinction event. 

Sara Callegaro et al, Recurring volcanic winters during the latest Cretaceous: Sulfur and fluorine budgets of Deccan Traps lavas, Science Advances (2023). DOI: 10.1126/sciadv.adg8284

Comment by Dr. Krishna Kumari Challa on November 28, 2023 at 10:01am

Study unveils the engagement of different cortical networks while humans are unconscious

States of unconsciousness, such as those that occur during sleep or while under the effect of anesthesia, have been the focus of countless past neuroscience studies. While these works have identified some brain regions that are active and inactive when humans are unconscious, the precise contribution of each of these regions to consciousness remains largely unclear.

Researchers recently carried out a study aimed at better understanding the activity of different regions of the cortex, the outer layer of the mammalian brain, during different states of unconsciousness, namely sleep and general anesthesia. Their paper, published in Neuron, identifies distinct cortical networks that are engaged during different states of unconsciousness.

What happens in the human brain when we are unconscious? And, what happens when we cannot be awakened?

This recent study on the states of unconsciousness focuses on sleep versus general anesthesia induced by the drug propofol.

The researchers carried out their study on patients diagnosed with epilepsy who had electrodes implanted in their brains as part of their medical treatment. By recording brain activity inside the brain, these electrodes help doctors monitor and treat epileptic seizures. 

They found that, compared to when they were awake, during sleep the brain was uniformly affected across patients, presenting simpler and reduced brain connections, as well as larger variability in the recorded activity.

All measures were more pronounced during propofol-induced anesthesia, but the brain involvement was not uniform; the changes in prefrontal regions were particularly prominent.

This indicates that during different forms of unconsciousness distinct parts of the brain are involved in different ways. These new findings in turn imply that going from unconscious to conscious may use different mechanisms depending on the nature of the unconscious state.

 Rina Zelmann et al, Differential cortical network engagement during states of un/consciousness in humans, Neuron (2023). DOI: 10.1016/j.neuron.2023.08.007

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