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Salk scientists unveil RNA capabilities that enable Darwinian evolution at a molecular scale, and bring researchers closer to producing autonomous RNA life in the laboratory.

Charles Darwin described evolution as “descent with modification.” Genetic information in the form of DNA sequences is copied and passed down from one generation to the next. But this process must also be somewhat flexible, allowing slight variations of genes to arise over time and introduce new traits into the population.

But how did all of this begin? In the origins of life, long before cells and proteins and DNA, could a similar sort of evolution have taken place on a simpler scale? Scientists in the 1960s, including Salk Fellow Leslie Orgel, proposed that life began with the “RNA World,” a hypothetical era in which small, stringy RNA molecules ruled the early Earth and established the dynamics of Darwinian evolution.

If you had to estimate the number of people in a room, without counting them one-by-one, by nature you would overcount them. That’s because, simply put from a Darwinian perspective of how we have evolved, it’s better to overcount potentially harmful agents and predators than to underestimate them.

This overcounting social behaviour is shown to be true in humans as well as animals. It’s certainly better to detect too many tigers (even if absent) during a jungle excursion than to miss a hungry one!

Now, EPFL neuroscientists show that if you experience hallucinations, especially when related to an illness like Parkinson’s disease, then you will overestimate the number of people in a room to a greater degree. They also show that if you have hallucinations but are asked to estimate the number of boxes in a room, which are inanimate control objects, then no extra over-estimation occurs, shedding light on the social nature of this overcounting. The results are published in Nature Communications.

Scientists created a highly accurate reference genome for one of the most important modern crops and found a rare example of how genes confer disease resistance in plants. Exploring sugarcane’s genetic code could help researchers develop more resilient and productive crops, with implications for both sugar production and biofuels.

The following is an interview with CRISPR co-discoverer and Nobel Prize-winner Dr. Jennifer Doudna.

Describe the “eureka moment” around CRISPR — the moment when you realized that this technology was not only possible but actually worked. How did you feel? Has your feeling changed since that eureka moment? If so, how?

There’s one moment that stands out in my mind, right at the time we realized what CRISPR could do and that we could “reprogram” it to edit specific sequences of DNA. I was cooking dinner and thinking about it, and I burst out laughing. My son was in the kitchen and he asked why I was laughing. So I explained it to him with a little drawing of a car zooming around, grabbing onto viruses, and chopping them up. I think my drawing did the trick, because he started laughing too.

Cyrus Brodén, orthopedic physician and researcher at Uppsala University Hospital and Uppsala University.

Administrative tasks take up a large share of a doctor’s working hours, reducing the time for patient contact and contributing to a stressful work situation. Researchers at Uppsala University Hospital and Uppsala University, in collaboration with Danderyd Hospital and the University Hospital of Basel, Switzerland, have shown in a new study that the AI model ChatGPT can write administrative medical notes up to ten times faster than doctors without compromising quality.

OpenAI on Friday revealed a voice-cloning tool it plans to keep tightly controlled until safeguards are in place to thwart audio fakes meant to dupe listeners.

A model called “Voice Engine” can essentially duplicate someone’s speech based on a 15-second audio sample, according to an OpenAI blog post sharing results of a small-scale test of the tool.

“We recognize that generating speech that resembles people’s voices has serious risks, which are especially top of mind in an election year,” the San Francisco-based company said.

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The effects of aging on the immune system

The aging immune system is associated with reduced lymphopoiesis, increased inflammation, and myeloid diseases due to alterations in self-renewing HSCs. During childhood, bal-HSCs predominate, thereby facilitating lymphopoiesis and adaptive immune responses.

Age increases my-HSCs, which reduces lymphopoiesis and enhances myelopoiesis. Myeloid-HSC origin and possible interconversions are unclear; however, removing my-HSCs in aged mice may reverse the aging phenotype.

Alzheimer’s is the most common form of dementia, affecting an estimated 6.7 million people in the US. Researchers seeking an effective treatment for the affliction have, over the last 30 years, focused their efforts on a protein known as amyloid beta (A-beta), which form clumps in the brain.

These clumps of A-beta proteins attack nerve cells, resulting initially in short-term memory impairment and later in the loss of judgment, language and thought processes.

Other researchers have previously developed an antibody which can identify and attach itself to A-beta proteins and delay the progression of Alzheimer’s in patients with early-to-mild cognitive impairment by up to 36%.