Comment

Comment by Dr. Krishna Kumari Challa on September 28, 2020 at 10:15am

First Compelling Evidence of Organisms That Eat Viruses as a Food Source

Two types of single-celled organisms found drifting in the waters of the Gulf of Maine off North America's coast just might be the first true virophages known to science.

Researchers identified the virus grazers after sifting nearly 1,700 plankton cells collected from the waters of the gulf and the Mediterranean Sea, and amplifying the DNA inside each and every one to create individualised genomic libraries.

In the gulf sample, half of the libraries contained snippets of genes from 50 or more different viruses. In the Mediterranean sample it was closer to a third of the sample.

Most of the virus sequences appeared to be from bacteriophages – pathogens that invade and replicate inside bacterial cells.

Bacteria are a common food source for marine protozoans, so finding their dinner came pre-infected isn't much of a surprise.

But representatives belonging to groups known as choanozoans and picozoans, both collected from the waters off North America, stood out as a little unusual.

For one thing, in many cases there was not a shred of bacterial DNA in sight. Without any signs of a bacterial brunch, it's hard to know how bacteriophage genes might have ended up inside the planktons' cells.

More compelling still is that the two completely different phyla of protozoans shared near-identical viral sequences, making it hard to argue that infection was responsible.

While the evidence for a diet of virus snacks could be considered circumstantial, it's not unlike finding dark crumbs dusting your toddler's fingers near an empty box of Oreos. Nobody's going to blame you for being suspicious.

https://www.frontiersin.org/articles/10.3389/fmicb.2020.524828/full

https://www.sciencealert.com/first-compelling-evidence-of-organisms...

Comment by Dr. Krishna Kumari Challa on September 28, 2020 at 10:08am

Scientists Have Found The Molecule That Allows Bacteria to 'Exhale' Electricity

For mouthless, lungless bacteria, breathing is a bit more complicated than it is for humans. We inhale oxygen and exhale carbon dioxide; Geobacter - a ubiquitous, groundwater-dwelling genus of bacteria - swallow up organic waste and 'exhale' electrons, generating a tiny electric current in the process.

https://www.livescience.com/electron-breathing-geobacter-microbes.html

https://www.sciencealert.com/bacteria-in-mud-breathe-through-giant-...

Comment by Dr. Krishna Kumari Challa on September 28, 2020 at 9:46am

Researchers show conscious processes in birds' brains for the first time

By measuring brain signals, a neuroscience research group has demonstrated for the first time that corvid songbirds possess subjective experiences. Simultaneously recording behavior and brain activity enabled the group  to show that crows are capable of consciously perceiving sensory input. Until now this type of consciousness has only been witnessed in humans and other primates, which have completely different brain structures to birds.

For humans and our nearest relatives in the animal kingdom, the nonhuman primates, our ability to perceive things consciously is localized in the cerebral cortex. Over many years research has discussed whether animals with brains that are structured completely differently, without a cerebral cortex, are also endowed with conscious perception. Until now however there has been no experimental neurological data to support such a claim.

In order to track conscious processes in birds, the Tübingen scientists trained two crows: they had to signal whether they had seen a stimulus on a screen by moving their heads. Most of the stimuli were perceptually unambiguous: different trials presented either bright figures or no stimulus at all, and the crows reliably signaled the presence or absence of these stimuli, respectively. However, some stimuli were so faint that they were at the threshold of perception: for the same faint stimulus, the crows sometimes indicated that they had seen it, whereas in other cases they reported that there was no stimulus. Here, the subjective perception of the crows came into play.

While the crows responded to the visual stimuli, the researchers simultaneously recorded the activity of individual nerve cells in the brain. When the crows reported having seen something, the nerve cells were active in the period between presentation of the stimulus and the behavioral response. If they did not perceive a stimulus, the nerve cells remained silent. Surprisingly, it was possible to predict the subjective experience of the crows with regard to the stimulus based on the activity of the nerve cells.

These results conclusively show that nerve cells at higher processing levels of the crow's brain are influenced by subjective experience, or more precisely, produce subjective experiences."

This means that in terms of evolutionary history the origins of consciousness could be far older and more widespread in the animal kingdom than previously thought. the capability of conscious experience can be realized in differently structured brains and independently of the cerebral cortex.

Nieder et al., A neural correlate of sensory consciousness in a corvid bird. Science (2020). science.sciencemag.org/cgi/doi … 1126/science.abb1447

https://phys.org/news/2020-09-conscious-birds-brains.html?utm_sourc...

Comment by Dr. Krishna Kumari Challa on September 28, 2020 at 9:40am

Metformin treatment linked to slowed cognitive decline

Metformin is the first-line treatment for most cases of type 2 diabetes and one of the most commonly prescribed medications worldwide, with millions of individuals using it to optimize their blood glucose levels.

A new research study, conducted over six years 

 has revealed an additional effect: individuals with type 2 diabetes who used metformin experienced slower cognitive decline with lower dementia rates than those who did not use the medication.

The findings provide new hope for a means of reducing the risk of dementia in individuals with type 2 diabetes, and potentially those without diabetes who number nearly 47 million people worldwide.

Diabetes Care (2020). DOI: 10.2337/dc20-0892

https://medicalxpress.com/news/2020-09-metformin-treatment-linked-c...

--

Scientists discover why tarantulas come in vivid blues and greens

https://phys.org/news/2020-09-scientists-tarantulas-vivid-blues-gre...

Comment by Dr. Krishna Kumari Challa on September 28, 2020 at 9:30am

Comment by Dr. Krishna Kumari Challa on September 28, 2020 at 9:27am

Ecologists confirm Alan Turing's theory for fairy circles

Fairy circles are one of nature's greatest enigmas and most visually stunning phenomena. An international research team has now, for the first time, collected detailed data to show that Alan Turing's model explains the striking vegetation patterns of the Australian fairy circles. In addition, the researchers showed that the grasses that make up these patterns act as "eco-engineers" to modify their own hostile and arid environment, thus keeping the ecosystem functioning.

Researchers used drone technology, spatial statistics, quadrat-based field mapping, and continuous data-recording from a field-weather station. With the drone and a multispectral camera, the researchers mapped the "vitality status" of the Triodia grasses (how strong and how well they grew) in five one-hectare plots and classified them into high- and low-vitality.

The systematic and detailed fieldwork enabled, for the first time in such an ecosystem, a comprehensive test of the 'Turing pattern' theory. Turing's concept was that in certain systems, due to random disturbances and a 'reaction-diffusion' mechanism, interaction between just two diffusible substances was enough to allow strongly patterned structures to spontaneously emerge. Physicists have used this model to explain the striking skin patterns in zebrafish or leopards for instance.

The data show that the unique gap pattern of the Australian fairy circles, which occur only in a small area east of the town of Newman, emerges from ecohydrological biomass-water feedbacks from the grasses. In fact, the fairy circles—with their large diameters of 4m, clay crusts from weathering and resultant water run-off—are a critical extra source of water for the dryland vegetation. Clumps of grasses increased shading and water infiltration around the nearby roots. With increasing years after fire, they merged more and more at the periphery of the vegetation gaps to form a barrier so that they could maximize their water uptake from the fairy circle's runoff. The protective plant cover of grasses could reduce soil-surface temperatures by about 25°C at the hottest time of the day, which facilitates the germination and growth of new grasses. In summary, the scientists found evidence both at the scale of the landscape and at much smaller scales that the grasses, with their cooperative growth dynamics, redistribute the water resources, modulate the physical environment, and thus function as "ecosystem engineers" to modify their own environment and better cope with the arid conditions.

Stephan Getzin et al, Bridging ecology and physics: Australian fairy circles regenerate following model assumptions on ecohydrological feedbacks, Journal of Ecology (2020). DOI: 10.1111/1365-2745.13493

https://phys.org/news/2020-09-ecologists-alan-turing-theory-austral...

Comment by Dr. Krishna Kumari Challa on September 28, 2020 at 6:59am

Antifungal preventive drugs reduce mortality risk following lung transplantation: Study

The retrospective study, published in the Annals of the American Thoracic Society, is the largest ever to evaluate the effectiveness of antifungal preventive drugs in lung transplant recipients who are particularly susceptible to invasive fungal infections. These infections are associated with a nearly threefold increase in mortality for lung transplant recipients.

The study showed that  the risk of death within the first year posttransplant is about twice as high in patients not receiving antifungal preventive treatment, compared with those receiving treatment.

https://www.atsjournals.org/doi/abs/10.1513/AnnalsATS.202003-267OC

Comment by Dr. Krishna Kumari Challa on September 28, 2020 at 6:16am

White supremacists believe in genetic ‘purity’. Science shows no such thing exists

Science does not support the idea of pure races with ancient origins. In the past few years, genetic sequencing of ancient and modern humans and related species has given us a flood of new information about how human populations have evolved.

The evidence reveals a history of ongoing genetic mingling, due to interbreeding between different populations and even species. Humans from different groups had children together, and even with Neanderthals and members of other now-extinct hominin species.

This mingling occurred constantly in the long process of human migration across the globe. Europeans inhabit one region of a large genetic continuum and are no more or less “pure” than any other population.

https://theconversation.com/white-supremacists-believe-in-genetic-p...

Comment by Dr. Krishna Kumari Challa on September 28, 2020 at 6:02am

Seven Warning Signs of Bogus Science

1. The discoverer pitches the claim directly to the media.

2. The discoverer says that a powerful establishment is trying to suppress his or her work.

3. The scientific effect involved is always at the very limit of detection.

4. Evidence for a discovery is anecdotal.

5. The discoverer says a belief is credible because it has endured for centuries.

6. The discoverer has worked in isolation.

7. The discoverer must propose new laws of nature to explain an observation.

https://quackwatch.org/related/signs/

Comment by Dr. Krishna Kumari Challa on September 28, 2020 at 5:56am

Body fat deep below the surface is a toxic risk, especially for your heart

BMI can’t provide information about the shape and size of potentially dangerous internal fat deposits, known as “visceral fat”. Over recent years it’s become apparent visceral fat can lead to disease, and good fat can turn into toxic fat when there is too much.

Various organs seem to accumulate visceral fat. This can be a problem because it can create and release damaging molecules and hormones into the blood. These are transported in the bloodstream, potentially causing health complications in distant parts of the body.

For example, toxic fat can release proteins that blunt the body’s sensitivity to insulin. Blood glucose levels then rise, potentially causing diabetes in the long term. Visceral fat can also stimulate uncontrolled cell growth and replication, potentially triggering some forms of cancer. A fatty liver is associated with metabolic diseases, and excess kidney fat interferes with the body’s fluid balance.

The heart is especially vulnerable

https://theconversation.com/body-fat-deep-below-the-surface-is-a-to...

• ‹ Previous
• 1
• …
• 714
• 715
• 716
• 717
• 718
• …
• 1042
• Next ›
• Page