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Comment by Dr. Krishna Kumari Challa on May 13, 2023 at 9:53am

New study puts a definitive age on Saturn's rings

A new study has delivered the strongest evidence yet that Saturn's rings are remarkably young—potentially answering a question that has boggled scientists for well over a century.

The research, published May 12 in the journal Science Advances, pegs the age of Saturn's rings at no more than 400 million years old. That makes the rings much younger than Saturn itself, which is about 4.5 billion years old.

The researchers arrived at that closure by studying what might seem like an unusual subject: dust.

Tiny grains of rocky material wash through Earth's solar system on an almost constant basis. In some cases, this flux can leave behind a thin layer of dust on planetary bodies, including on the ice that makes up Saturn's rings.

In the new study, researchers set out to put a date on Saturn's rings by studying how rapidly this layer of dust builds up.

Think about the rings like the carpet in your house. If you have a clean carpet laid out, you just have to wait. Dust will settle on your carpet. The same is true for the rings.

It was an arduous process: From 2004 to 2017, the research team used an instrument called the Cosmic Dust Analyzer aboard NASA's late Cassini spacecraft to analyze specks of dust flying around Saturn. Over those 13 years, the researchers collected just 163 grains that had originated from beyond the planet's close neighborhood. But it was enough. Based on their calculations, Saturn's rings have likely been gathering dust for only a few hundred million years.

The planet's rings, in other words, are new phenomena, arising (and potentially even disappearing) in what amounts to a blink of an eye in cosmic terms.

Sascha Kempf, Micrometeoroid infall onto Saturn's rings constrains their age to no more than a few hundred million years, Science Advances (2023). DOI: 10.1126/sciadv.adf8537. www.science.org/doi/10.1126/sciadv.adf8537

Comment by Dr. Krishna Kumari Challa on May 13, 2023 at 8:49am

Fearful memories of pain stored in the prefrontal cortex could shape the experience of pain later in life

While pain and fear are very different experiences, past studies showed that they can sometimes be closely related to one another. For instance, when many animals and humans are in dangerous or life-threatening situations, acute fear can suppress their perception of pain, allowing them to fully focus their attention on what is happening to them.

Conversely, research showed that when humans experience high levels of pain, they can create long-term and associative fear memories that make them fearful of situations that they associate with the pain they felt. These memories can in turn increase their sensitivity to pain or lead to the development of unhelpful behavioral patterns aimed at avoiding pain.

The increase in the intensity with which animals or humans perceive pain after very painful past experiences could be liked to their fearful anticipation of pain. The exact neural underpinnings of this process, however, are still poorly understood.

Researchers have recently carried out a study aimed at better understanding which regions of the mice brain stores very painful experiences and how these stored memories can affect future experiences of pain. Their findings, published in Nature Neuroscience, suggest that these memories are stored in the prefrontal cortex, the area covering the front part of the mammalian brain.

The researchers conducted a series of experiments on adult mice using a neural tagging method and optogenetic techniques. During these experiments, the mice received small electric shocks on their feet and were conditioned to become fearful of receiving these shocks again. The team also used optogenetic techniques to either activate or suppress different neural circuits in the mice's brain, to determine how this would affect their sensitivity to pain.

They found that in mice that long-term associative fear memory stored in neuronal engrams in the prefrontal cortex determines whether a painful episode shapes pain experience later in life.

Furthermore, under conditions of inflammatory and neuropathic pain, prefrontal fear engrams expand to encompass neurons representing nociception and tactile sensation, leading to pronounced changes in prefrontal connectivity to fear-relevant brain areas. Conversely, silencing prefrontal fear engrams reverses chronically established hyperalgesia and allodynia.

These results reveal that a discrete subset of prefrontal cortex neurons can account for the debilitating comorbidity of fear and chronic pain and show that attenuating the fear memory of pain can alleviate chronic pain itself.

Alina Stegemann et al, Prefrontal engrams of long-term fear memory perpetuate pain perception, Nature Neuroscience (2023). DOI: 10.1038/s41593-023-01291-x

Comment by Dr. Krishna Kumari Challa on May 13, 2023 at 8:33am

What happens when fish encounter their robotic counterparts?

Study observes the interactions between live fish and fish-like robots

In recent decades, engineers have created a wide range of robotic systems inspired by animals, including four legged robots, as well as systems inspired by snakes, insects, squid and fish. Studies exploring the interactions between these robots and their biological counterparts, however, as still relatively rare.

So recently researchers set out to explore what happens when live fish are placed in the same environment as a robotic fish. Their findings, published in Bioinspiration & Biomimetics, could both inform the development of fish-inspired robots and shed some new light on the behavior of real fish.

During their field experiments, the researchers observed an exciting phenomenon where live fish were observed following the swimming robotic fish. They  are eager to further explore the underlying principles behind this phenomenon and gain a deeper understanding of this 'fish following' behaviour.

 The robotic fish used in their experiments was carefully designed to replicate the appearance, body shape, and movements of koi fish, large and colorful freshwater fish originating from Eastern Asia.

In their experiments, the researchers placed one or two prototypes of their koi fish-like robot in the same tank with one or more live fishes. They then observed how the fish behaved in the presence of this robot and assessed whether their behavior varied based on how many other live fish were present in the tank with them.

Through extensive experimentation, they discovered that live fish exhibit significantly lower proactivity when alone, and the most proactive case is one where a robotic fish is interacting with two real fish. In addition, their experiments on parameter variation indicated that live fish may respond more proactively to robotic fish that swim with high frequency and low amplitude, but they may also move together with the robotic fish at high frequency and high amplitude.

The researchers' observations shed an interesting new light on the collective behavior of fish, which could potentially guide the design of additional fish-like robots. 

Ziye Zhou et al, Proactivity of fish and leadership of self-propelled robotic fish during interaction, Bioinspiration & Biomimetics (2023). DOI: 10.1088/1748-3190/acce87

This video is not related to this research work. I just posted it here to get an idea of robotic fish swimming along with real fish in the ocean

Comment by Dr. Krishna Kumari Challa on May 13, 2023 at 6:16am

This distortion depends on the shape of the object and the world that object is reflecting, both of which researchers may have incomplete information about. In addition, the glossy object may have its own color and texture that mixes with reflections. Plus, reflections are two-dimensional projections of a three-dimensional world, which makes it hard to judge depth in reflected scenes.

The researchers found a way to overcome these challenges. Their technique, known as ORCa (which stands for Objects as Radiance-Field Cameras), works in three steps. First, they take pictures of an object from many vantage points, capturing multiple reflections on the glossy object.

Then, for each image from the real camera, ORCa uses machine learning to convert the surface of the object into a virtual sensor that captures light and reflections that strike each virtual pixel on the object’s surface. Finally, the system uses virtual pixels on the object’s surface to model the 3D environment from the point of view of the object.

Imaging the object from many angles enables ORCa to capture multiview reflections, which the system uses to estimate depth between the glossy object and other objects in the scene, in addition to estimating the shape of the glossy object. ORCa models the scene as a 5D radiance field, which captures additional information about the intensity and direction of light rays that emanate from and strike each point in the scene.

The additional information contained in this 5D radiance field also helps ORCa accurately estimate depth. And because the scene is represented as a 5D radiance field, rather than a 2D image, the user can see hidden features that would otherwise be blocked by corners or obstructions.

In fact, once ORCa has captured this 5D radiance field, the user can put a virtual camera anywhere in the scene and synthesize what that camera would see, Dave explains. The user could also insert virtual objects into the environment or change the appearance of an object, such as from ceramic to metallic.

It 's especially challenging to go from a 2D image to a 5D environment. You have to make sure that mapping works and is physically accurate, so it is based on how light travels in space and how light interacts with the environment. 

The researchers evaluated their technique by comparing it with other methods that model reflections, which is a slightly different task than ORCa performs. Their method performed well at separating out the true color of an object from the reflections, and it outperformed the baselines by extracting more accurate object geometry and textures.

They compared the system’s depth estimations with simulated ground truth data on the actual distance between objects in the scene and found ORCa’s predictions to be reliable.

Consistently, with ORCa, it not only estimates the environment accurately as a 5D image, but to achieve that, in the intermediate steps, it also does a good job estimating the shape of the object and separating the reflections from the object texture.

https://news.mit.edu/2023/using-reflections-shiny-objects-camera-0510

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Comment by Dr. Krishna Kumari Challa on May 13, 2023 at 6:13am

Using reflections to see the world from new points of view

As a car travels along a narrow city street, reflections off the glossy paint or side mirrors of parked vehicles can help the driver glimpse things that would otherwise be hidden from view, like a child playing on the sidewalk behind the parked cars.

Drawing on this idea, researchers have created a computer vision technique that leverages reflections to image the world. Their method uses reflections to turn glossy objects into “cameras,” enabling a user to see the world as if they were looking through the “lenses” of everyday objects like a ceramic coffee mug or a metallic paper weight.

Using images of an object taken from different angles, the technique converts the surface of that object into a virtual sensor which captures reflections. The AI system maps these reflections in a way that enables it to estimate depth in the scene and capture novel views that would only be visible from the object’s perspective. One could use this technique to see around corners or beyond objects that block the observer’s view.

This method could be especially useful in autonomous vehicles. For instance, it could enable a self-driving car to use reflections from objects it passes, like lamp posts or buildings, to see around a parked truck.

The researchers  have shown that any surface can be converted into a sensor with this formulation that converts objects into virtual pixels and virtual sensors. This can be applied in many different areas.

In real life, exploiting these reflections is not as easy as just pushing an enhance button. Getting useful information out of these reflections is pretty hard because reflections give us a distorted view of the world.

Part 1

Comment by Dr. Krishna Kumari Challa on May 12, 2023 at 10:39am

Growing crops under solar panels provide food and energy at the same time

 Imagine growing greens in your back yard under a solar panel, and then juicing them in a blender powered by the same energy. A new  project is working to make that a reality. By growing spinach under different solar panels,  researchers are measuring how the process affects both plant growth and the electrical output of the panels. Known as agrivoltaics, the fairly new sustainable practice integrates solar panels with crops, making simultaneous use of land for both food and energy production. Agrivoltaics has the potential to address several pressing issues around sustainability.

https://www.ualberta.ca/folio/2023/05/could-growing-crops-under-sol....

Comment by Dr. Krishna Kumari Challa on May 12, 2023 at 10:26am

New Synthetic Blood Clotting System Could Help Stop Internal Bleeding

Blood clots are one of the body's most important natural defense systems, a mechanism for plugging internal and external gaps to keep us alive. However, in cases where the body is losing a lot of blood, the clotting process can't keep up. This is where a new synthetic replacement could come in.

Researchers have developed a two-component system that targets internal injuries without causing any unwanted damage of its own. The two components match the body's platelets (cell fragments that trigger clotting) and fibrinogen (a protein that helps clots to form). So far, the synthetic process has only been tested on mice, but it effectively triggered the blood clotting part of the natural hemostasis reaction to wounds and proved significantly better at stopping bleeding than previous approaches.

The idea of using two components allows selective gelation of the hemostatic system as the concentration is enhanced in the wound, mimicking the end effect of the natural clotting cascade.

The first part of the system is a biocompatible polymer nanoparticle called PEG-PLGA that is engineered to bind to whatever platelets the body can provide while injured. Platelets are drawn to the site of an injury, which in turn carries in these bound nanoparticles.

The second part of the system is a polymer that takes the place of fibrinogen and starts creating clumps through a reaction with the nanoparticles. The team describes this second component as a crosslinker, essentially getting the particles that have formed around a wound to join together.

Crucially, the researchers designed the particles in a form where they wouldn't accumulate in places where they shouldn't (in the wrong spots, blood clots can also be dangerous to our health) by having them only crosslink at a high enough concentration.

In a tiny initial mouse trial, not only did the synthetic system prove highly effective, but also it lasted longer than normal blood clots would. Moreover, the system didn't trigger any unwanted immune system reactions in the animals.

https://onlinelibrary.wiley.com/doi/full/10.1002/adhm.202202756

Comment by Dr. Krishna Kumari Challa on May 12, 2023 at 9:52am

Cold Water Therapy Might Do More Harm Than Good. 

Immersion in cold water is definitely an activity that divides people – some love it, others hate it. But many now practice it weekly or even daily in the belief that it's good for their mental and physical health.

Cold water therapy, as it has come to be known, can take the form of outdoor swimming – in lakes, rivers or the ocean – cold showers, or even ice baths. It has been used for a while by sportspeople as a way to reduce muscle soreness and speed up recovery time – with people typically spending about ten minutes after exercise in cold water that's about 10 to 15 °C (50 to 59 °F).

Cold water has also been used to help treat symptoms of depression, pain, and migraine. Indeed, there are many accounts of how cold water therapy has changed lives, cured broken hearts, and helped people during difficult times.

While many studies have shown benefits linked to ice baths and post-exercise recovery, research from 2014 found there could be a placebo effect going on here.

Part 1

Comment by Dr. Krishna Kumari Challa on May 11, 2023 at 10:27am

A New Urine Test Could Be a Simple Way to Check For Cancer

Diagnosing cancer early makes a significant difference to the chances of a patient's successful recovery, which is why cheap, non-invasive screening tests are so important.

A new diagnostic tool development by researchers 

needs little more than a sample of urine, making it possible for some types of cancer to be screened at home much like a pregnancy test. No need for a trip to the doctor or to hospital, and no need for expensive scanning procedures or bothersome blood tests.

While the test might be simple, the technology behind it is rather sophisticated, relying on the presence of enzymes that are specific to the emergence of different cancers.

Researchers developed a new type of nanoparticle with a coating of proteins tagged with an array of DNA sequences. When cancer-related enzymes encounter a nanoparticle in the blood, they snip off a protein specific to that enzyme. Excreted out of the body through the urine, the sequences connected to the protein can then be read like a barcode, identifying the presence of cancer.

Tested on mice via an injection, the same nanoparticles could eventually be developed to be taken orally, through an inhaler, or as a local treatment such as a cream, according to the researchers.

Not only do the nanoparticle's various DNA barcodes have the potential to identify whether or not a tumor is present, they could also be able to distinguish between types of tumors, and spot if a tumor has metastasized (spread to other parts of the body). All of this is vital information for developing and targeting treatments.

The nanoparticle sensors were shown to detect five different enzymes produced by tumors. Up to 46 different DNA barcodes can potentially be expressed in a single sample, once the technology has been scaled up further.

https://www.nature.com/articles/s41565-023-01372-9

Comment by Dr. Krishna Kumari Challa on May 11, 2023 at 9:27am

New method for delivering an antioxidant directly to mitochondria in the liver, mitigating oxidative stress

Mitochondria are microscopic organelles found within cells, and are by far the largest producer of the molecule adenosine triphosphate (ATP), which provides energy to many processes in living cells. The process by which mitochondria synthesize ATP generates a large amount of reactive oxygen species (ROS), chemical groups that are highly reactive.

In a healthy cell, the ROS are controlled by the mitochondria; however, when this balance is lost, the excess ROS damages the mitochondria and subsequently cells and tissues. This phenomenon, known as oxidative stress, can cause premature aging and disease. The ROS that cause oxidative stress can be controlled by antioxidants.

A research team has developed a system to deliver antioxidants to mitochondria to mitigate the effects of excess ROS. Their findings have been published in Scientific Reports.

They  developed a drug delivery system which they named CoQ₁₀-MITO-Porter. This system consists of the antioxidant molecule Coenzyme Q₁₀ (CoQ₁₀)—which is also required by mitochondria for ATP production—encapsulated by a lipid nanoparticle that would target mitochondria. 

Variations of the formula for the synthesis of CoQ₁₀-MITO-Porter were tested, and their structures were examined with electron microscopy. CoQ₁₀-MITO-Porter was administered to mice models with acetaminophen-induced liver damage. Acetaminophen overdoses cause excess ROS in mitochondria, which in turn damages cells in the liver. CoQ₁₀-MITO-Porter was transported primarily to the liver and measurably reduced the damage caused by ROS. A further discovery was that downsized CoQ₁₀-MITO-Porter particles with more efficient packaging of CoQ₁₀ were more effective at treating liver damage than the original formulation.

Mitsue Hibino et al, A System that Delivers an Antioxidant to Mitochondria for the treatment of Drug-Induced Liver Injury, Scientific Reports (2023). DOI: 10.1038/s41598-023-33893-7. www.nature.com/articles/s41598-023-33893-7

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