Comment

Comment by Dr. Krishna Kumari Challa on August 30, 2022 at 11:04am

During sprouting, seedlings rapidly elongate their stems to break through the covering soil to capture sunlight as fast as possible. Normally, the stem slows down its growth after exposure to sunlight. But the stem can lengthen rapidly again if the plant is competing with surrounding plants for sunlight, or in response to warm temperatures to increase distance between the hot ground and the plant's leaves. While both environmental conditions—canopy shade and warm temperatures—induce stem growth, they also reduce yield.

In this study, the scientists compared plants growing in canopy shade and warm temperatures at the same time—a condition that mimics high crop density and climate change. The scientists used the model plant Arabidopsis thaliana, as well as tomato and a close relative of tobacco, because they were interested to see if all three plant species were affected similarly by this environmental condition.

Across all three species, the team found that the plants grew extremely tall when simultaneously trying to avoid the shade created by neighboring plants and being exposed to warmer temperatures. On a molecular level, the researchers discovered that transcription factor PIF7, a protein that helps turn genes "on" and "off," was the dominant player driving the increased rapid growth. They also found that the growth hormone auxin increased when the crops detected neighboring plants, which fostered growth in response to simultaneous warmer temperatures. This synergistic PIF7-auxin pathway allowed the plants to respond to their environments and adapt to seek the best growing conditions.

A related transcription factor, PIF4, also stimulated stem elongation during warm temperatures. However, when shade and increased temperatures were combined, this factor no longer played an important role.

The researchers think that there is another player, yet to be discovered, that is boosting the effect of PIF7 and auxin. They hope to explore this unknown factor in future studies.

Global temperatures are increasing, so we need food crops that can thrive in these new conditions.

Scientists now  identified key factors that regulate plant growth during warm temperatures, which will help us to develop better-performing crops to feed future generations.

 PIF7 is a master regulator of thermomorphogenesis in shade, Nature Communications (2022). DOI: 10.1038/s41467-022-32585-6

Part 2

**

Comment by Dr. Krishna Kumari Challa on August 30, 2022 at 11:02am

How light and temperature work together to affect plant growth

Plants lengthen and bend to secure access to sunlight. Despite observing this phenomenon for centuries, scientists do not fully understand it. Now, Salk scientists have discovered that two plant factors—the protein PIF7 and the growth hormone auxin—are the triggers that accelerate growth when plants are shaded by canopy and exposed to warm temperatures at the same time.

The findings, published in Nature Communications on August 29, 2022, will help scientists predict how plants will respond to climate change—and increase crop productivity despite the yield-harming global temperature rise.

Right now, we grow crops in certain densities, but our findings indicate that we will need to lower these densities to optimize growth as our climate changes. Understanding the molecualr basis of how plants respond to light and temperature will allow us to fine-tune crop density in a specific way that leads to the best yields.

Part 1

Comment by Dr. Krishna Kumari Challa on August 30, 2022 at 10:05am

Autoimmune disorders increase risk of cardiovascular disease

About 5% of the population in the world suffer from multiple autoimmune disorders. Examples are rheumatoid arthritis, psoriasis, systemic sclerosis, lupus erythematosus and type I diabetes. Although earlier research has suggested associations between some of these disorders and a higher risk of cardiovascular disease, these studies were often too small and limited to selected autoimmune or selected cardiovascular conditions to draw conclusive evidence on the necessity of cardiovascular disease prevention among patients with autoimmune disease, until now.

An international research team now presented the outcome of a thorough epidemiological investigation into possible links between 19 of the most common autoimmune disorders and cardiovascular disease. The results of the study show that patients with autoimmune disease have a substantially higher risk (between 1.4 and 3.6 times depending on which autoimmune condition) of developing cardiovascular disease than people without an autoimmune disorder. This excess risk is comparable to that of type 2 diabetes, a well-known risk factor for cardiovascular disease. The research shows for the first time that cardiovascular risks affect autoimmune disease as a group of disorders, rather than selected disorders individually.

In the research paper, which will be published in The Lancet, the authors show that the group of 19 autoimmune disorders they have studied accounts for about 6% of cardiovascular events. Importantly, excess cardiovascular risk was visible across the whole cardiovascular disease spectrum, beyond classical coronary heart disease, including infection-related heart disorders, heart inflammation, as well as thromboembolic and degenerative heart disorders, suggesting the implications of autoimmunity on cardiovascular health are likely to be much broader than originally thought.

Furthermore, the excess risk was not explained by traditional cardiovascular risk factors such as age, sex, socioeconomic status, blood pressure, BMI, smoking, cholesterol and type 2 diabetes. Another noteworthy finding: the excess risk is particularly high among patients with autoimmune disorders under 55 years and suggests that autoimmune disease is particularly important in causing premature cardiovascular disease, with the potential to result in a disproportionate loss of life years and disability.

 Autoimmune diseases and cardiovascular risk: a populationbased study on 19 autoimmune diseases and 12 cardiovascular diseases in 22 million individuals in the UK, The Lancet (2022). DOI: 10.1016/S0140-6736(22)01349-6

Comment by Dr. Krishna Kumari Challa on August 27, 2022 at 11:59am

A battery powered by moisture from the air

Comment by Dr. Krishna Kumari Challa on August 26, 2022 at 11:38am

Eye movements in REM sleep mimic gazes in the dream world

When our eyes move during REM sleep, we’re gazing at things in the dream world our brains have created, according to a new study by researchers.

REM sleep — named for the rapid eye movements associated with it — has been known since the 1950s to be the phase of sleep when dreams occur. But the purpose of the eye movements has remained a matter of much mystery and debate. 

This new work showed that these eye movements aren’t random. They’re coordinated with what's happening in the virtual dream world of the mouse.This work gives us a glimpse into the ongoing cognitive processes in the sleeping brain and at the same time solves a puzzle that’s triggered the curiosity of scientists for decades.

some experts hypothesized that these REM movements may be following scenes in the dream world, but there was little way to test it, and the experiments that could be done (noting a dreamers’ eye direction and then waking them up to ask where they were looking in the dream) provided contradictory results. Many researchers wrote off REM movements as random actions, perhaps to keep the eyelids lubricated.

Given much more advanced technology, researchers now were able to look at “head direction” cells in the brains of mice, who also experience REM sleep. These cells act something like a compass, and their activity shows researchers which direction the mouse perceives itself as heading. 

The team simultaneously recorded data from these cells about the mouse’s heading directions while monitoring its eye movements. Comparing them, they found that the direction of eye movements and of the mouse’s internal compass were precisely aligned during REM sleep, just as they do when the mouse is awake and moving around.  

The research team found that the same parts of the brain — and there are many of them — coordinate during both dreaming and wakefulness, lending credence to the idea that dreams are a way of integrating information gathered throughout the day. 

How those brain regions work together to produce this generative ability is the mystery .

https://www.science.org/doi/10.1126/science.abp8852

Comment by Dr. Krishna Kumari Challa on August 26, 2022 at 9:16am

Physicists entangle more than a dozen photons efficiently

.Physicists  have managed to entangle more than a dozen photons efficiently and in a defined way. They are thus creating a basis for a new type of quantum computer. 

The phenomena of the quantum world, which often seem bizarre from the perspective of the common everyday world, have long since found their way into technology. For example, entanglement: a quantum-physical connection between particles that links them in a strange way over arbitrarily long distances. It can be used, for example, in a quantum computer—a computing machine that, unlike a conventional computer, can perform numerous mathematical operations simultaneously. However, in order to use a quantum computer profitably, a large number of entangled particles must work together. They are the basic elements for calculations, so-called qubits.

Photons, the particles of light, are particularly well suited for this because they are robust by nature and easy to manipulate. Researchers  have now succeeded in taking an important step towards making photons usable for technological applications such as quantum computing: For the first time, a research team generated up to 14 entangled photons in a defined way and with high efficiency.

The trick to this experiment was that they used a single atom to emit the photons and interweave them in a very specific way. To do this, the researchers placed a rubidium atom at the center of an optical cavity—a kind of echo chamber for electromagnetic waves. With laser light of a certain frequency, the state of the atom could be precisely addressed. Using an additional control pulse, the researchers also specifically triggered the emission of a photon that is entangled with the quantum state of the atom.

They  repeated this process several times and in a previously determined manner.

In between, the atom was manipulated in a certain way—in technical jargon: rotated. In this way, it was possible to create a chain of up to 14 light particles that were entangled with each other by the atomic rotations and brought into a desired state.

Because the chain of photons emerged from a single atom, it could be produced in a deterministic way. This means: in principle, each control pulse actually delivers a photon with the desired properties.

 Philip Thomas et al, Efficient generation of entangled multiphoton graph states from a single atom, Nature (2022). DOI: 10.1038/s41586-022-04987-5

Comment by Dr. Krishna Kumari Challa on August 25, 2022 at 12:36pm

New research on the risks of lead exposure from bullets used in big game hunting

The lead in some bullets used for hunting deer, moose, and elk is toxic to the humans who eat the harvested meat and to scavenger animals that feast on remains left in the field.

Comment by Dr. Krishna Kumari Challa on August 25, 2022 at 9:56am

Here's what a black hole sounds like, according to NASA.

Data Sonification: Black Hole at the Center of the Perseus Galaxy Cluster (X-ray)

Comment by Dr. Krishna Kumari Challa on August 25, 2022 at 9:44am

Experiment on YouTube reveals potential to 'inoculate' users against misinformation

Fact-checkers can only rebut a fraction of the falsehoods circulating online. We need to teach people to recognize the misinformation playbook, so they understand when they are being misled.

https://phys.org/news/2022-08-youtube-reveals-potential-inoculate-m...

Comment by Dr. Krishna Kumari Challa on August 24, 2022 at 12:01pm

Study shows 90% of marine species at risk of extinction by 2100 if greenhouse gas emissions are not curbed

An international team of researchers has found that approximately 90% of all marine life on Earth will be at risk of extinction by 2100 if greenhouse gas emissions are not curbed. In their paper published in the journal Nature Climate Change, the group outlines their study of thousands of marine species and how greenhouse gas emissions might impact them in the future.

Greenhouse gas emissions impact the world's climate in two ways. They raise the temperature of the atmosphere (and by extension, Earth's surfaces and bodies of water) by holding in heat, and in the case of CO₂ emissions, they make water more acidic, like carbonated soft drinks. And as emissions continue to be pumped into the atmosphere despite dire warnings from scientists around the world, more research is being conducted to learn about its possible impact. In this new effort, the researchers took a broad look at the impact of greenhouse gas emissions on ocean life.

The work involved estimating the impact of certain levels of greenhouse gas emissions on marine life in the future. They looked specifically at 25,000 species, including fish, bacteria, plants and protozoans living in the top 100 meters of the world's oceans. They found that under the worst scenario, in which emissions lead to global atmospheric temperature increases of 3 to 5 degrees Celsius, approximately 90% of all marine life will disappear. They also found that if emissions are cut to the extent outlined by the Paris Climate Agreement, which would keep global temperature increases to below 2 degrees Celsius, then the risk of extinction would be reduced by approximately 98%.

The researchers also found that larger top predators are more at risk than smaller predators, as are fish species  in areas where they are heavily fished by humans. Those at lowest risk, on the other hand, include small, short-lived species. Notably, Earth has not seen a die-off as great as these projections since the Great Dying 252 million years ago.

Daniel G. Boyce et al, A climate risk index for marine life, Nature Climate Change (2022). DOI: 10.1038/s41558-022-01437-y

• ‹ Previous
• 1
• …
• 229
• 230
• 231
• 232
• 233
• …
• 839
• Next ›
• Page