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Feb 14, 2023

How One of the Most Important Algorithms in Math Made Color TV Possible

Posted by in categories: information science, mathematics

A key algorithm that quietly empowers and simplifies our electronics is the Fourier transform, which turns the graph of a signal varying in time into a graph that describes it in terms of its frequencies.

Packaging signals that represent sounds or images in terms of their frequencies allows us to analyze and adjust sound and image files, Richard Stern, professor of electrical and computer engineering at Carnegie Mellon University, tells Popular Mechanics. This mathematical operation also makes it possible for us to store data efficiently.

The invention of color TV is a great example of this, Stern explains. In the 1950s, television was just black and white. Engineers at RCA developed color television, and used Fourier transforms to simplify the data transmission so that the industry could introduce color without tripling the demands on the channels by adding data for red, green, and blue light. Viewers with black-and-white TVs could continue to see the same images as they saw before, while viewers with color TVs could now see the images in color.

Feb 14, 2023

Will CRISPR Cure Cancer?

Posted by in categories: biotech/medical, genetics, health, neuroscience

One question for Brad Ringeisen, a chemist and executive director of the Innovative Genomics Institute. Founded by Nobel Prize-winning biochemist Jennifer Doudna, it aims to bridge revolutionary gene-editing tool development to affordable and accessible solutions in human health and climate.

Will CRISPR cure cancer?

We’re always thinking about: What are those targets in the future? Cancer is one of those things. The biggest impact is going to be what’s called systemic delivery, or in vivo delivery. There’s been one example of this in the community right now—to treat a liver disease. Intellia Therapeutics, a biotech company, has shown that you can actually intravenously apply CRISPR-Cas9 treatment. (CRISPR is the guide RNA, the targeting molecule, and Cas9 is the cutting molecule that edits DNA.) It can go to the liver and target the liver cells, and make edits at a high enough efficacy to treat genetic liver disease. The problem is that the liver is the easiest. It’s like the garbage can of the body. Pretty much anything that you put into the body is ultimately going to find its way to the liver. So that’s absolutely the easiest tissue to deliver to. But trying to deliver to a solid tumor, or to the brain, is much more difficult.

Feb 14, 2023

A new class of medicinal compounds that target RNA

Posted by in categories: biotech/medical, chemistry

A team of undergraduate and graduate chemistry students in Jennifer Hines’ lab at Ohio University recently uncovered a new class of compounds that can target RNA and disrupt its function. This discovery identified a chemical scaffold that could ultimately be used in the development of RNA-targeted medicines to treat bacterial and viral infections, as well as cancer and metabolic diseases.

RNA is chemically like DNA but also controls the extent to which the DNA’s instructions are carried out within a living cell. It is this essential regulatory role in the function of the cell that makes RNA such an attractive target.

“Trying to target RNA is at the forefront of medicinal chemistry research with enormous potential for treating diseases,” said Hines, professor of chemistry and biochemistry in the College of Arts and Sciences. “However, there are relatively few compounds known to directly modulate RNA activity which makes it challenging to design new RNA-targeted therapeutics.”

Feb 14, 2023

What If Neanderthals Had Outlived Homo Sapiens?

Posted by in category: evolution

An anthropologist imagines a world in which Neanderthals—and their relationships with the environment and one another—survived evolution.

Feb 14, 2023

Stephen Wolfram explores the broader picture of what’s going on inside ChatGPT and why it produces meaningful text

Posted by in category: neuroscience

Discusses models, training neural nets, embeddings, tokens, transformers, language syntax.

Feb 14, 2023

Even the best models for reading facial expressions may be partly subjective

Posted by in category: futurism

Does someone look angry or sad? You can probably offer an answer to that question based on the information you can see just by looking at their face. That’s because facial expressions—or a combination of different small facial movements—can be read by other humans to help understand what a person might be feeling at that exact moment.

Since Darwin’s seminal work on the evolutionary origins of of emotion, scientists have been trying to find out which specific combinations of facial movements best represent our six : happy, surprise, fear, disgust, anger and sadness. So far, researchers have offered a range of theories—or models—to define which facial movements best match each emotion, but until now no one has been able to show which one is most accurate.

Now, a new study by a team of European researchers led by the University of Glasgow and University of Amsterdam has begun to answer that question. The new study, which is published in Science Advances, shows that even the best models for predicting emotions from facial expressions fall short of the judgment of real human participants. Moreover, different humans themselves may read different emotions from the same facial expression, making it even harder to pinpoint exactly which facial movements are systematically linked with certain emotions.

Feb 14, 2023

Link found between chronic pain and overactive pyramidal neurons during sleep

Posted by in categories: biotech/medical, neuroscience

A team of neuroscientists at the New York University School of Medicine has found a link between chronic pain and overactive pyramidal neurons during sleep periods. In their study, published in the journal Nature Neuroscience, the group conducted experiments with injured mice experiencing chronic pain.

Prior research has shown that there is often a link between chronic pain and insomnia. After experiencing a neural injury of some sort, many patients are left with some degree of lasting pain. This tends to result in poor sleep and sometimes insomnia. Once that happens, the pain becomes worse, and over time becomes chronic. But why this happens has been a mystery. In this new effort, the team in New York conducted experiments with hoping to find the answer.

The work involved inducing chronic pain in mice by damaging two of the three branches that make up a group of sciatic nerves. Doing so led to sensitivity in the legs. The researchers scanned the brains of each of the mice before and after the damage. They observed that pyramidal neurons in the part of the cerebral cortex responsible for sensation processing in the skin became more active. And over the course of several weeks, the activity increased, peaking during non-REM sleep.

Feb 14, 2023

Scientists study increased fatigue and daytime sleep reported after ischemic stroke

Posted by in categories: biotech/medical, neuroscience

Approximately 9,000 people are admitted to Norwegian hospitals with stroke each year. About half of these patients feel exhausted afterwards, and many patients sleep more during the day than before the stroke. These after-effects are challenging and significantly affect patients’ everyday life.

However, we still have a limited understanding of which factors lead to increased and daytime sleep after stroke. Our research group therefore wanted to investigate whether cognitive and emotional complaints are related to increased fatigue and sleep during the day.

Our results were recently published in an article in the journal Frontiers in Neurology.

Feb 14, 2023

Social isolation triggers astrocyte-mediated deficits in learning and memory

Posted by in categories: biotech/medical, neuroscience

Here is an important reason to stay in touch with friends and family: social isolation causes memory and learning deficits and other behavioral changes. Many brain studies have focused on the effects social deprivation has on neurons, but little is known about the consequences for the most abundant brain cell, the astrocyte.

Researchers at Baylor College of Medicine working with animal models report in the journal Neuron that during , become hyperactive, which in turn suppresses brain circuit function and memory formation. Importantly, inhibiting astrocyte hyperactivity reversed the cognitive deficits associated with .

“One thing we have learned during the COVID pandemic is that social isolation can influence cognitive functions, as previous studies suggested,” said co-first author, Yi-Ting Cheng, graduate student in Dr. Benjamin Deneen’s lab at Baylor. “This motivated co-first author Dr. Junsung Woo and me to further investigate the effects of social isolation in the brain, specifically in astrocytes.”

Feb 14, 2023

Determining the driving radiation flux on capsule in Hohlraum for indirect drive inertial confinement fusion

Posted by in category: futurism

In 2021, the fusion yield of 1.35 MJ was produced at NIF by using indirect drive inertial confinement fusion (ICF), indicating that indirect drive ICF has reached ignition. However, the driving radiation flux on capsule inside Hohlraums is still a puzzle in indirect drive ICF studies. The energy deficit at NIF is still neither well understood nor solved. In this paper, we proposed a scheme to determine the driving radiation flux on the capsule by using the combination of the shock wave technique and the reemitted radiation flux measurement. In this scheme, a witness sample is placed in the Hohlraum center as the surrogate of the capsule. The shock velocity in the witness sample is measured by a streaked optical pyrometer from one side, and the temporal reemitted radiation flux is measured by a space-resolved flat response x-ray detector. Then, the peak of the radiation flux is determined by the shock velocity, and the time behavior of the radiation flux is determined by the reemitted flux through the numerical simulation of radiation hydrodynamic code. The rules for designing the witness sample and an example of applying this scheme to determine the driving radiation flux on capsule inside the octahedral spherical Hohlraum are presented in detail.