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Comment by Dr. Krishna Kumari Challa on September 7, 2023 at 3:06pm

India's Lunar Lander Has Detected 'Movement' on The Moon: But Is It Seismic Activity?

India's Chandrayaan-3 mission may have just recorded the first seismic data on the Moon since the 1970s. If confirmed to be natural seismic data, it could finally help scientists understand how the Moon's insides are arranged. The rumblings were recorded by the Vikram lander's onboard Instrument for Lunar Seismic Activity (ILSA). It's the first Micro Electro Mechanical Systems (MEMS) technology-based instrument on the Moon and it was was able to record the seismic rumbles of the mission's Pragyan rover moving around on the surface. But it also picked up what could be a natural event, such as a quake or an impact.

ILSA's primary objective is to measure ground vibrations generated by natural quakes, impacts, and artificial events. The vibrations recorded during the rover's navigation on August 25, 2023, are depicted in the figure," the Indian Space Research Organisation (ISRO) wrote in a statement.

Additionally, an event, seemingly natural, recorded on August 26, 2023, is also shown. The source of this event is currently under investigation.

This is tremendously exciting; to date, the best seismic data we have for the Moon was that collected by the Apollo program in the late 1960s and 1970s. Scientists have been itching to get their hands on more since we still don't know how the Moon's inner layers are arranged . Seismic data would go a long way to resolving that.

Even though it's only been a few weeks since ISRO landed on the Moon, it's already conducted a bunch of scientific observations and detected the first elements at the south pole.

Now both lander and rover are currently in sleep mode. That's because it's now night where they are on the Moon, which lasts 14 days or so.

Vikram and Pragyan, like other lunar missions before them, are solar powered, which means they "sleep" at night, when their batteries can't recharge.
Vikram and Pragyan will emerge from slumber on 22 September, when they will recommence their explorations of the mysterious south pole of the Moon.

Source: ISRO

Comment by Dr. Krishna Kumari Challa on September 7, 2023 at 2:59pm

What Was the First Animal to Evolve a Brain?

In the absence of a precise definition of brain, pinning down its origins is difficult. But scientists have a theory.

Having a brain is so necessary to human experience that it’s almost impossible to imagine any life without it. However, many living organisms don’t have brains, and going back far enough in time will lead to an ancestor of our own that was equally brainless. So, when exactly did brains evolve?

Scientists home in on the brain’s evolutionary origins by sorting out the animals without brains. Sponges have no neurons, so they are easy to discount, and while the more sophisticated jellyfish and sea anemones have a network of neurons, they have no central neural “headquarters” characteristic of a brain. 

About 600 million years ago, another group of animals evolved that had bilateral symmetry, meaning that they had a front and a back. “The front is where the nervous system crystallizes because that’s the bit of the animal that’s meeting the environment head on”. The first brain-like mass of neurons likely evolved at the front end of a long, thin, worm-like animal. Everything else that descended from that has a descendent of that neutral structure.

Today, there are many species, including some invertebrates such as the octopus, with brains that work similar to ours. These brains control perception, behaviour, and higher functions like memory. They are complex and wondrous, and they all evolved from a clump of neurons in the head of a worm.

Comment by Dr. Krishna Kumari Challa on September 7, 2023 at 2:50pm

Plant biology discovery is ‘like a switch between life and death’

Comment by Dr. Krishna Kumari Challa on September 7, 2023 at 12:49pm

Researchers issue warning over Chrome extensions that access private data

Google Chrome browser extensions expose users to hackers who can easily tap into their private data, including social security numbers, passwords and banking information, according to researchers at the University of Wisconsin-Madison (UW-M).

The researchers further uncovered vulnerabilities involving passwords that are stored in plain text within HTML source code on web sites of some of the world's largest corporate giants, including Google, Amazon, Citibank, Capital One and the Internal Revenue Service.

The problem stems from the manner in which extensions access internal web page code. 

Google offers thousands of extensions that users install to handle calendar events, password management, ad blocking, email access, bookmark storage, translation and search activities.

While such extensions help expand upon browser capabilities and make browsing easier, they also expose stored data to intruders.

In the absence of any protective measures, as seen on websites like IRS.gov, Capital One, USENIX, Google, and Amazon, sensitive data such as SSNs and credit card information are immediately accessible to all extensions running on the page. This presents a significant security risk, as private data is left vulnerable

The threat remains despite protective measures introduced by Google this year that have been embraced by most browsers. The protocol placed stricter limits on what kinds of information extensions can access.

But there remains no protective layer between web pages and browser extensions, so bad actors can still evade detection.

The researchers described "the alarming discovery" of passwords stored in plain text HTML web page source files.

A significant percentage of extensions possess the necessary permissions to exploit these vulnerabilities and researchers have  identified 190 extensions "that directly access password fields."

The extension faults stemmed from two key procedural violations in coding: least privilege and complete mediation.

Least privilege refers to the principle that users and systems should be granted only the lowest level of access privilege required to complete tasks. Any unnecessary privilege should be barred. Default access states should be on "deny" and not "allow."

Complete mediation refers to evaluation of each and every access request, with no deviations or exceptions.

Asmit Nayak et al, Exposing and Addressing Security Vulnerabilities in Browser Text Input Fields, arXiv (2023). DOI: 10.48550/arxiv.2308.16321

The researchers proposed two means to address the problem. The first is a JavaScript add-on for all extensions that provide solid cover for sensitive input fields.

The second proposal is to add a browser feature that alerts users when an attempt is made to access sensitive data.

Comment by Dr. Krishna Kumari Challa on September 6, 2023 at 11:55am

Microplastics from tires are polluting our waterways

Urban storm water particles from tire wear were the most prevalent microplastic a new  study has found. Published in Environmental Science & Technology, the study showed that in storm water runoff during rain approximately 19 out of every 20 microplastics collected were tire wear particles with anywhere from 2 to 59 particles per liter of water.

Pollution of our waterways by microplastics is an emerging environmental concern due to their persistence and accumulation in aquatic organisms and ecosystems.

Storm water runoff which contains a mixture of sediment, chemical, organic and physical pollutants, is a critical pathway for microplastics to washed off from urban environments during rain and into local aquatic habitats.

Tire rubber contains up to 2,500 chemicals with the contaminants that leach from tires considered more toxic to bacteria and microalgae than other plastic polymers.

Sediment samples collected from the inlet and outlet of a constructed storm water wetland contained between 1,450 to 4,740 particles in every kilogram of sediment, with more microplastics in the sediment at the inlet than the outlet, indicating the wetland's ability to remove them from storm water.

Microplastics that enter constructed wetlands for storm water drainage systems settle in the sediment and form a biofilm, leading to their accumulation over time, removing them from storm water runoff.

These  findings show that both constructed wetlands and the storm water capture device are strategies that could be potentially used to prevent or at least decrease the amount of microplastics tire wear particles being transported from storm water into our waterways.

Shima Ziajahromi et al, Microplastics and Tire Wear Particles in Urban Stormwater: Abundance, Characteristics, and Potential Mitigation Strategies, Environmental Science & Technology (2023). DOI: 10.1021/acs.est.3c03949

Comment by Dr. Krishna Kumari Challa on September 6, 2023 at 10:23am

Synchronizing your internal clocks may help mitigate jet lag, effects of aging

Traveling to faraway places is a great way to seek out new experiences, but jet lag can be an unpleasant side effect. Adjusting to a new time zone is often accompanied by fatigue, difficulty sleeping, and a host of other problems that can turn an otherwise exciting adventure into a miserable trip.

Jet lag is caused by a difference between the circadian system—the body's internal clock—and the surrounding environment. Around the turn of the century, scientists began to recognize that the body has multiple internal clocks, calibrated in different ways, and that jet lag-like symptoms can result when these clocks drift out of sync with each other. This can happen in several ways and grows more prevalent with age.

A team of scientists  developed a theoretical model to study the interactions between multiple internal clocks under the effects of aging and disruptions like jet lag. The article, "A minimal model of peripheral clocks reveals differential circadian re-entrainment in aging," appeared in the journal Chaos on Sept. 5, 2023.

Modern research has shown that circadian clocks are present in almost every cell and tissue in the body. Each relies on its own set of cues to calibrate; the brain's clock depends on sunlight, for instance, while the peripheral organs calibrate at mealtime.

Conflicting signals, such as warm weather during a short photoperiod or nighttime eating—eating when your brain is about to rest—can confuse internal clocks and cause desynchrony.

At this point, little is known about how the body's various internal clocks affect each other. The added complexity of accounting for multiple clocks means researchers tend to use simplified models. Most studies primarily focus on one particular time cue or a single clock. Important gaps remain in our understanding of the synchronization of multiple clocks under conflicting time cues.

Researchers now took a different approach, building a mathematical framework that accounts for this complex interplay between systems. Their model features two populations of coupled oscillators that mimic the natural rhythms of circadian cycles. Each oscillator influences the others while simultaneously adjusting based on unique external cues.

Using this model, the team was able to explore how such a coupled system could be disrupted and what makes the effect worse. They found that common symptoms of aging, such as weaker signals between circadian clocks and a lower sensitivity to light, result in a system that is more vulnerable to disruptions and slower to recover.

They also landed on a new method to speed up recovery from jet lag and similar disruptions. According to their results, the way to better sleep is through the stomach.

Having a larger meal in the early morning of the new time zone can help overcome jet lag. Constantly shifting meal schedules or having a meal at night is discouraged, as it can lead to misalignment between internal clocks. 

The authors plan to investigate the other side of the equation and identify the factors that result in more resilient internal clocks. Such discoveries could result in recommendations to prevent jet lag in the first place, or to keep the circadian system healthy into old age.

A minimal model of peripheral clocks reveals differential circadian re-entrainment in aging, Chaos An Interdisciplinary Journal of Nonlinear Science (2023). DOI: 10.1063/5.0157524

Comment by Dr. Krishna Kumari Challa on September 6, 2023 at 9:55am

Why are male kidneys more vulnerable to disease than female kidneys? Mouse study points to testosterone

Female kidneys are known to be more resilient to disease and injury, but males need not despair. A new  study published in Developmental Cell describes not only how sex hormones drive differences in male and female mouse kidneys, but also how lowering testosterone can "feminize" this organ and improve its resilience.

By exploring how differences emerge in male and female kidneys during development, we can better understand how to address sex-related health disparities for patients with kidney diseases.

Researchers identified more than 1,000 genes with different levels of activity in male and female mouse kidneys. The differences were most evident in the section of the kidney's filtering unit known as the proximal tubule, responsible for reabsorbing most of the nutrients such as glucose and amino acids back into the blood stream. Most of these sex differences in gene activity emerged as the mice entered puberty and became even more pronounced as they reached sexual maturity. Because female kidneys tend to fare better in the face of disease or injury, the researchers were interested how the gene activity of kidneys becomes "feminized" or "masculinized"—and testosterone appeared to be the biggest culprit. 

To feminize the kidneys of male mice, two strategies worked equally well: castrating males before puberty and thus lowering their natural testosterone levels, or removing the cellular sensors known as androgen receptors that respond to male sex hormones. Intriguingly, three months of calorie restriction—which is an indirect way to lower testosterone—produced a similar effect. Accordingly, calorie restriction has already been shown to mitigate certain types of kidney injuries in mice. To re-masculinize the kidneys of the castrated males, the researchers only needed to inject testosterone. Similarly, testosterone injection masculinized the kidneys of females who had their ovaries removed before puberty. The scientists performed some similar experiments with mouse livers. Although this organ also displays sex-related differences, the hormones and underlying factors driving these differences are very different than those at play in the kidney. This suggests that these sex-related organ differences emerged independently during evolution. To test whether the same genes are involved in sex-related kidney differences in humans, the scientists analyzed a limited number of male and female donor kidneys and biopsies. When it came to genes that differed in their activity between the sexes, there was a modest overlap of the human genes with the mouse genes.

Andrew P McMahon & colleagues, Direct androgen receptor control of sexually dimorphic gene expression in the mammalian kidney, Developmental Cell (2023). DOI: 10.1016/j.devcel.2023.08.010. www.cell.com/developmental-cel … 1534-5807(23)00406-9

Comment by Dr. Krishna Kumari Challa on September 5, 2023 at 7:46am

Eye movements decrease while effortfully listening to speech: study

After a certain age, approximately 40% of people experience some degree of hearing loss. While age-related hearing loss is most prevalent in adults over the age of 65, it can start occurring far earlier than that, when people are in their 40s or 50s.

Despite their widespread use, existing diagnostic techniques might be unable to detect earlier signs of hearing loss, such as the loss of the ability to hear speech in crowded or noisy environments. Some researchers have thus been trying to devise viable techniques to detect subtler forms of hearing loss, so that they can be addressed early, before they are irreparable. To this end, neuroscientists have recently been exploring the relationship between effortful listening and eye movements. Their most recent paper, published in The Journal of Neuroscience, suggests eye movements tend to decrease while young adults are placing greater effort in trying to hear speech.

Past studies highlighted several different physiological responses that occur while one is effortfully listening. One that is commonly mentioned in existing literature is a change in pupil size, which can be measured using pupillometry, a technique that relies on a camera to record eyes and calculate the diameter of pupils at different points in time.

 Research investigating the auditory cortex in animals—that is, the brain region responding to sound—found that when animals reduce their movements, the auditory cortex becomes more sensitive to sound.  so researchers thought that reduced eye movements could also be associated with higher auditory sensitivity to speech.

When researchers tested this,  they found that under the more effortful listening conditions, that is, when the degree of speech masking through background noise was high, individuals' eye movements decreased as reflected in longer fixation durations and reduced gaze dispersion, compared to more favorable listening conditions.

M. Eric Cui et al, Eye Movements Decrease during Effortful Speech Listening, The Journal of Neuroscience (2023). DOI: 10.1523/JNEUROSCI.0240-23.2023

Comment by Dr. Krishna Kumari Challa on September 4, 2023 at 8:55am

For the new paper, the authors conducted both a review, or meta-analysis, of previous research and their own original data analysis.

For the meta-analysis, they looked at 22 traits across 199 studies including millions of male-female co-parents, engaged pairs, married pairs or cohabitating pairs. The oldest study was conducted in 1903.

In addition, they used a dataset called the UK Biobank to study 133 traits, including many that are seldom studied, across almost 80,000 opposite-sex pairs in the United Kingdom.

Across both analyses, traits like political and religious attitudes, level of education, and certain measures of IQ showed particularly high correlations.

Traits around substance use also showed high correlations, with heavy smokers, heavy drinkers and teetotalers tending strongly to partner up with those with similar habits. Meanwhile, traits like height and weight, medical conditions and personality traits showed far lower but still positive correlations. For instance, the correlation for neuroticism was .11. For some traits, like extroversion, there was not much of a correlation at all. People have all these theories that extroverts like introverts or extroverts like other extroverts, but the fact of the matter is that it's about like flipping a coin: Extroverts are similarly likely to end up with extroverts as with introverts.

In the meta-analysis, the researchers found "no compelling evidence" on any trait that opposites attract. In the UK Biobank sample, they did find a handful of traits in which there seemed to be a negative correlation, albeit small.

Those included: chronotype (whether someone is a "morning lark" or "night owl"), tendency to worry and hearing difficulty.

More research must be done to unpack those findings.

These findings suggest that even in situations where we feel like we have a choice about our relationships, there may be mechanisms happening behind the scenes of which we aren't fully aware.

The authors note that couples share traits for a variety of reasons: Some grow up in the same area. Some are attracted to people who are similar to them. Some grow more similar the longer they are together.

Horwitz, T.B. et al, Evidence of correlations between human partners based on systematic reviews and meta-analyses of 22 traits and UK Biobank analysis of 133 traits. Nature Human Behavior (2023). DOI: 10.1038/s41562-023-01672-z www.nature.com/articles/s41562-023-01672-z

Part 2

Comment by Dr. Krishna Kumari Challa on September 4, 2023 at 8:52am

Evidence shows that, in love, opposites don't actually attract

Despite some conventional wisdom to the contrary, opposites don't actually attract.

That's the takeaway from a sweeping research  analysis of more than 130 traits and including millions of couples over more than a century.

The findings demonstrate that birds of a feather are indeed more likely to flock together.

The study, published today in the journal Nature Human Behaviour, confirms what individual studies have hinted at for decades, defying the age-old adage that "opposites attract."

It found that for between 82% and 89% of traits analyzed—ranging from political leanings to age of first intercourse to substance use habits—partners were more likely than not to be similar.

For only 3% of traits, and only in one part of their analysis, did individuals tend to partner with those who were different than them.

Aside from shedding light on unseen forces that may shape human relationships, the research has important implications for the field of genetic research. A lot of models in genetics assume that human mating is random. This study shows this assumption is probably wrong, noting that what is known as "assortative mating"—when individuals with similar traits couple up—can skew findings of genetic studies.

Part 1

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