Comment

Comment by Dr. Krishna Kumari Challa on November 21, 2022 at 9:46am

Why Scientists Are Listening to Coral Reefs

Comment by Dr. Krishna Kumari Challa on November 21, 2022 at 9:13am

Some Sugar Free Gummy Bears Are In Reality Laxatives! 

Comment by Dr. Krishna Kumari Challa on November 19, 2022 at 11:13am

Making mosquitoes' love songs fall on deaf ears

A team of researchers  have developed a new method that may help control mosquito populations. The annoying buzzing sound that mosquitoes make when flying inspired this technique.

Mosquitoes are not just a nuisance to people sitting outside on warm summer evenings. They also spread deadly diseases that kill thousands of people every year, including dengue, malaria, and the Zika virus. Therefore, it is vital to reduce mosquito populations around the world. Unfortunately, commonly used insecticides have become less effective over time because mosquitoes have developed resistance. They also have a negative impact on the environment. Therefore, alternative methods are needed for mosquito control.

One promising method for controlling mosquitoes takes advantage of perhaps their most annoying feature—their high-pitched buzzing. Females create this sound as they fly around seeking sources of blood. Male mosquitoes listen specifically for this characteristic high-pitched noise. Shaped like antennas, male mosquito ears vibrate at the same frequency as the female mosquito's wings. When a female flies by, the male's ears detect this frequency and resonate, sending a signal to their brain that helps them identify a potential mate.

A team of researchers  tested whether they could control mosquito mating behavior by altering the frequency at which male mosquitoes listen. By making the male mosquitoes' ears go "out of tune," they sought to influence their mating behavior.

he team first identified the involvement of the major neurotransmitter serotonin in the auditory system of the insect. Serotonin plays an important role in nervous systems and brains of various animals', influencing a wide range of behaviors.

After demonstrating serotonin in the mosquito auditory system, the team's next step was to manipulate serotonin levels. To do this, they used a method called "laser doppler vibrometry." This involves using a laser as a highly sensitive measurement tool to detect changes in the nanoscale vibrations of mosquito ears after exposure to serotonin-related compounds.

The researchers discovered that after feeding mosquitoes a serotonin-inhibiting compound, the male ears' vibration frequency decreased. When they gave the mosquitoes glucose laced with a compound that inhibited serotonin, both the range of frequencies the mosquitoes responded to, and their response itself, were reduced.

The next step in the development of a potential auditory-based "birth control" will involve identifying the exact receptors responsible for tuning the ears of mosquitoes. This could enable researchers to administer targeted compounds to disrupt mating behavior. 

Yifeng Y. J. Xu, YuMin M. Loh, Tai-Ting Lee, Takuro S. Ohashi, Matthew P. Su, Azusa Kamikouchi. Serotonin modulation in the male Aedes aegypti ear influences hearing. Frontiers in Physiology, 2022; 13 DOI: 10.3389/fphys.2022.931567

**

Comment by Dr. Krishna Kumari Challa on November 19, 2022 at 10:59am

Messel boa: Live birth in a 47-million-year-old snake

team of scientists, including Senckenberg’s Krister Smith, has discovered the world’s first fossil evidence of live birth in snakes. The fossil they examined came from the Hessian UNESCO World Heritage Site “Messel Pit.” In the study, published in the journal “The Science of Nature,” the researchers describe bones of snake embryos discovered in the mother’s body. The finding shows that viviparous snakes already existed at least 47 million years ago.

Most reptiles alive today lay eggs; this so-called oviparity is their most common mode of reproduction. But there are exceptions: Numerous species of lizards and snakes are known to deviate from the norm and give birth to their offspring alive – viviparously. Fossil preservation of reproductive events is generally very rare. In total, only two fossil records of viviparous land reptiles have been discovered to date. Scientists have now succeeded in describing the world’s first fossil evidence of a viviparous snake.

The fossil Messelophis variatus, from a family of boa-like snakes, is about 50 centimeters long, dates from the Eocene, and is related to modern-day dwarf boas from Central America. The species is among the most common snakes known from Messel. Nevertheless, this specimen,  is about 47 million years old.

It is a pregnant female with at least two embryos found in the posterior third of her trunk area. These bones were located quite a distance behind the stomach – if they were part of the snake’s prey, they would have already been digested this far back in the intestine and would no longer be recognizable. Thus, they must represent the boa’s embryos. The fact that the bones are from very young snakes, yet already further developed than in an unlaid egg, supports the assumption that scientists are dealing with a pregnant, viviparous female.

In live births, the young remain in the female’s body until they are viable – eliminating the need for a protective eggshell. This is considered an advantageous evolutionary strategy for reptiles in cold climates, as the temperature inside the female’s body is more stable and thus safer for their offspring. Therefore, many of today’s viviparous lizards and snakes have evolved in rather cooler climates. “During the Eocene, however, the Earth was dominated by a persistent greenhouse climate with warm temperatures, a high carbon dioxide content in the atmosphere, and ice-free poles. Around the Messel Lake, average temperatures at that time were about 20 degrees Celsius, and winter temperatures did not fall below freezing. Why the boas gave birth to live offspring 47 million years ago in spite of this fact is still unknown. Perhaps additional fossils from this unique site will help us solve this mystery!

Mariana Chuliver et al, Live birth in a 47-million-year-old snake, The Science of Nature (2022). DOI: 10.1007/s00114-022-01828-3

Comment by Dr. Krishna Kumari Challa on November 19, 2022 at 9:50am

Down syndrome, like Alzheimer's, is a double-prion disorder

The brains of people with Down syndrome develop the same neurodegenerative tangles and plaques associated with Alzheimer's disease and frequently demonstrate signs of the neurodegenerative disorder in their forties or fifties. A new study from researchers shows that these tangles and plaques are driven by the same amyloid beta (Aß) and tau prions that they showed are behind Alzheimer's disease in 2019.

Prions begin as normal proteins that become misshapen and self-propagate. They spread through tissue like an infection by forcing normal proteins to adopt the same misfolded shape. In both Alzheimer's and Down syndrome, as Aß and tau prions accumulate in the brain, they cause neurological dysfunction that often manifests as dementia.

Tau tangles and Aß plaques are evident in most people with Down syndrome by age 40, according to the National Institute on Aging, with at least 50% of this population developing Alzheimer's as they age.

The new study, published Nov. 7, 2022, in Proceedings of the National Academy of Sciences, highlights how a better understanding of Down syndrome can lead to new insights about Alzheimer's, as well.

Carlo Condello et al, Aβ and tau prions feature in the neuropathogenesis of Down syndrome, Proceedings of the National Academy of Sciences (2022). DOI: 10.1073/pnas.2212954119

Comment by Dr. Krishna Kumari Challa on November 19, 2022 at 9:38am

Earth now weighs six ronnagrams: New metric prefixes voted in

Say hello to ronnagrams and quettameters: International scientists gathered in France voted on Friday for new metric prefixes to express the world's largest and smallest measurements, prompted by an ever-growing amount of data.

It marks the first time in more than three decades that new prefixes have been added to the International System of Units (SI), the agreed global standard for the metric system.

Joining the ranks of well-known prefixes like kilo and milli are ronna and quetta for the largest numbers—and ronto and quecto for the smallest.

The change was voted on by scientists and government representatives from across the world attending the 27th General Conference on Weights and Measures, which governs the SI and meets roughly every four years at Versailles Palace, west of Paris.

The UK's National Physical Laboratory, which led the push for the new prefixes, confirmed that the resolution had passed in a statement.

The prefixes make it easier to express large amounts—for example, always referring to a kilometer as 1,000 meters or a millimeter as one thousandth of a meter would quickly become cumbersome.

Since the SI was established in 1960, scientific need has led to a growing number of prefixes. The last time was in 1991, when chemists wanting to express vast molecular quantities spurred the addition of zetta and yotta.

A yottameter is a one followed by 24 zeroes.

But even the mighty yotta is not enough to handle the world's voracious appetite for data.

So the Earth weighs approximately six ronnagrams,which is a six followed by 27 zeroes !

Jupiter, that's about two quettagrams—a two followed by 30 zeros.

Source: AFP

https://phys.org/news/2022-11-earth-ronnagrams-metric-prefixes-vote...

Comment by Dr. Krishna Kumari Challa on November 19, 2022 at 9:34am

A butterfly-stroke-like soft robotic swimmer that is fast and efficient

Comment by Dr. Krishna Kumari Challa on November 19, 2022 at 7:24am

What is a 'Carbon Cage,' and why are you stuck in one right now?

This knowledge is extremely important
Our current carbon-heavy economic system creates bars around us that stop effective climate change action. Here's why: The world is too accustomed to the luxuries and privileges which depend on co2 emissions

Comment by Dr. Krishna Kumari Challa on November 18, 2022 at 11:19am

How an Alzheimer’s gene ravages the brain

No gene variant is a bigger risk factor for Alzheimer’s disease than one called APOE4. But exactly how the gene spurs brain damage has been a mystery. A study has now linked APOE4 with faulty cholesterol processing in the brain, which in turn leads to defects in the insulating sheaths that surround nerve fibres and facilitate their electrical activity. Preliminary results hint that these changes could cause memory and learning deficits. And the work suggests that drugs that restore the brain’s cholesterol processing could treat the disease.

Comment by Dr. Krishna Kumari Challa on November 18, 2022 at 11:09am

Study shows hundreds of thousands of tons of bacteria are being released by melting glaciers

A team of researchers affiliated with multiple institutions across Europe, the U.K. and Canada has found that hundreds of thousands of tons of bacteria are currently being released annually into the environment by melting glaciers in the northern latitudes. In their paper published in the journal Communications Earth & Environment, the group describes sampling glacial runoff from multiple sites in Europe, North America and Greenland.

As climate change progresses, doomsday reports from around the world have proliferated. One alarming claim is that a virus or strain of bacteria will emerge from ancient ice that is impervious to the human immune system, killing off most, if not all, of humankind. In this new effort, the researchers have joined a growing effort to take samples of melting runoff from glaciers to learn more about their microbial ecosystems as a means to discover whether a threat exists, and if so, what sort.

The researchers did not study the bacteria individually, and thus did not spot any species that might pose a threat to human health. They did note that most of the bacteria were killed by the sun soon after exposure, suggesting that even if a human pathogen is among them, the chance of infection is slight. Bacteria in water samples, the researchers note, tend to have pigments that absorb sunlight, which further adds to warming in northern regions.

Ian T. Stevens et al, Spatially consistent microbial biomass and future cellular carbon release from melting Northern Hemisphere glacier surfaces, Communications Earth & Environment (2022). DOI: 10.1038/s43247-022-00609-0

• ‹ Previous
• 1
• …
• 405
• 406
• 407
• 408
• 409
• …
• 1037
• Next ›
• Page