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The way a cell fails to divide after copying its DNA can determine its fate

Cell division is one of the most fundamental and complex processes underpinning life. In human cells, thousands of molecules coordinate with one another in highly precise steps, all within a fraction of a second. But things don’t always go as planned.

Before a cell divides into two, it must first copy its DNA, so that each new cell receives a complete set. Occasionally, what can happen is, a cell successfully copies its DNA but then fails to split into two. When this happens, the cell is left with two copies of its DNA—a condition known as whole genome duplication (WGD).

One way to picture this is to imagine photocopying a document. Normally, you would make two copies and place one in each folder. In whole genome duplication, the copies are made but not separated, leaving one folder with both copies.

Proton beam timing tool could check radiotherapy energy before nearly every treatment

Proton beams are not only used in sophisticated nuclear physics experiments. Today, they are becoming increasingly popular in radiotherapy, where they are an irreplaceable tool for destroying cancer cells. Doctors and physicists can enhance their precision thanks to two solutions developed at the Cyclotron Center Bronowice of the Institute of Nuclear Physics, Polish Academy of Sciences.

In oncology, it is crucial to precisely eliminate cancer cells while causing as little damage as possible to healthy cells. For physicists, on the other hand, it is essential to have a precise understanding of the conditions under which they conduct their experiments. In the case of proton beams, used in radiotherapy and nuclear physics experiments, knowing the kinetic energy of the particles is key.

World Science Festival

Does quantum mechanics actually imply that every possible outcome of every decision happens somewhere in an expansive reality? And if so, what does that mean for probability, free will, and our understanding of the universe itself?

Brian Greene sits down with David Deutsch, widely regarded as the father of quantum computing, to examine what many physicists are still reluctant to accept about their own theory. They explore why the many-worlds interpretation isn’t just a philosophical curiosity, what the wave function is really telling us about reality, and how decision theory may rescue probability in a fully deterministic multiverse. Deutsch also introduces constructor theory, his framework for rethinking the foundations of physics entirely and explains why the questions we’ve been trained not to ask might be the most important ones in all of science.

This program is part of the Rethinking Reality series, supported by the John Templeton Foundation.

Participant: David Deutsch.
Moderator: Brian Greene.

#worldsciencefestival #briangreene #cosmology #astrophysics.

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Clinical impact of cardiac magnetic resonance imaging in myocardial infarction with non-obstructive coronary arteries: a prospective multicentre cohort study

Background Cardiac magnetic resonance (CMR) may radiologically identify or confirm underlying pathophysiologies in myocardial infarction with non-obstructive coronary arteries (MINOCA), however, there are scant prospective data evaluating the impact on routine clinical care.

Methods In a multicentre international cohort study of MINOCA, clinical diagnosis, diagnostic certainty and intended clinical management were prospectively determined before and again after CMR. The primary outcome was a composite of change in clinical diagnosis and/or management. Secondary outcomes were individual components of the primary outcome, change in diagnostic certainty and number-needed-to-test for deprescription of dual antiplatelet therapy (DAPT). Predictors of the primary outcome were evaluated by multivariable logistic regression analysis.

Results In 320 patients, CMR was associated with change in diagnosis and/or management in 63% (95% CI 57% to 68%, p0.001) and significantly increased diagnostic certainty (8÷10 post-CMR (5–9) vs 6/10 pre-CMR (4–7), p0.0001). Relevant predictors of the primary outcome on multivariable analysis were early CMR (≤14 days), absence of atheroma on coronary angiography and significant pre-CMR diagnostic uncertainty (≤5/10); CMR changed diagnosis and/or management in 80% of individuals with all three predictors versus 40% in those with none. In individuals where treating physicians initially chose to prescribe DAPT despite no obstructive culprit lesion, number-needed-to-test by CMR for DAPT deprescription was 3.

Negative effects of artificial sweeteners may pass on to next-generation, study suggests

Health organizations are starting to raise concerns about the potential long-term impacts of artificial sweeteners, which taste sweet but—unlike sugar—contain no calories, suggesting they could interfere with energy metabolism and increase the eventual risk of diabetes or cardiovascular disease.

Now a new study in mice indicates that the popular sweeteners sucralose and stevia have negative effects on the gut microbiome and gene expression, potentially compromising metabolic health, which can be transmitted between generations.

“We found it intriguing that despite the growing consumption of these additives, the prevalence of obesity and metabolic disorders such as insulin resistance has not declined,” said Dr. Francisca Concha Celume of the Universidad de Chile, lead author of the article in Frontiers in Nutrition.

You have no free will at all | Stanford professor Robert Sapolsky

Become a Big Think member to unlock expert classes, premium print issues, exclusive events and more: https://bigthink.com/membership/?utm_… How your biology and environment make your decisions for you, according to Dr. Robert Sapolsky.

Up next, Your reptilian brain, explained ► • Your reptilian brain, explained | Robert S…

Robert Sapolsky, PhD is an author, researcher, and professor of biology, neurology, and neurosurgery at Stanford University. In this interview with Big Think’s Editor-in-Chief, Robert Chapman Smith, Sapolsky discusses the content of his most recent book, “Determined: The Science of Life Without Free Will.”

Being held as a child, growing up in a collectivist culture, or experiencing any sort of brain trauma – among hundreds of other things – can shape your internal biases and ultimately influence the decisions you make. This, explains Sapolsky, means that free will is not – and never has been – real. Even physiological factors like hunger can discreetly influence decision making, as discovered in a study that found judges were more likely to grant parole after they had eaten.

This insight is key for interpreting human behavior, helping not only scientists but those who aim to evolve education systems, mental health research, and even policy making.

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