saint

Resurfaced in my feed. Obvious in retrospect.

Many microbes and cells are in deep sleep, waiting for the right moment to activate.

Harsh conditions like lack of food or cold weather can appear out of nowhere. In these dire straits, rather than keel over and die, many organisms have mastered the art of dormancy. They slow down their activity and metabolism. Then, w

Sitting around in a dormant state is actually the norm for the majority of life on Earth: By some estimates, 60% of all microbial cells are hibernating at any given time. Even in organisms whose entire bodies do not go dormant, like most mammals, some cellular populations within them rest and wait for the best time to activate.

“Life is mainly about being asleep.”

Because dormancy can be triggered by a variety of conditions, including starvation and drought, the scientists pursue this research with a practical goal in mind: “We can probably use this knowledge in order to engineer organisms that can tolerate warmer climates,” Melnikov said, “and therefore withstand climate change.”

Balon is notably absent from Escherichia coli and Staphylococcus aureus, the two most commonly studied bacteria and the most widely used models for cellular dormancy. By focusing on just a few lab organisms, scientists had missed a widespread hibernation tactic, Helena-Bueno said. “I tried to look into an under-studied corner of nature and happened to find something.”

“Most microbes are starving,” said Ashley Shade, a microbiologist at the University of Lyon who was not involved in the new study. “They’re existing in a state of want. They’re not doubling. They’re not living their best life.”

“This is not something that’s unique to bacteria or archaea,” Lennon said. “Every organism in the tree of life has a way of achieving this strategy. They can pause their metabolism.”

“Before the invention of hibernation, the only way to live was to keep growing without interruptions,” Melnikov said. “Putting life on pause is a luxury.”

It’s also a type of population-level insurance. Some cells pursue dormancy by detecting environmental changes and responding accordingly. However, many bacteria use a stochastic strategy. “In randomly fluctuating environments, if you don’t go into dormancy sometimes, there’s a chance that the whole population will go extinct” through random encounters with disaster, Lennon said. In even the healthiest, happiest, fastest-growing cultures of E. coli, between 5% and 10% of the cells will nevertheless be dormant. They are the designated survivors who will live should something happen to their more active, vulnerable cousins.

More fundamentally, Melnikov and Helena-Bueno hope that the discovery of Balon and its ubiquity will help people reframe what is important in life. We all frequently go dormant, and many of us quite enjoy it. “We spend one-third of our life asleep, but we don’t talk about it at all,” Melnikov said. Instead of complaining about what we’re missing when we’re asleep, maybe we can experience it as a process that connects us to all life on Earth, including microbes sleeping deep in the Arctic permafrost.

Valtonen’s goal is to put CPUs back in their rightful, ‘central’ role. In order to do that, he and his team are proposing a new paradigm. Instead of trying to speed up computation by putting 16 identical CPU cores into, say, a laptop, a manufacturer could put 4 standard CPU cores and 64 of Flow Computing’s so-called parallel processing unit (PPU) cores into the same footprint, and achieve up to 100 times better performance. Valtonen and his collaborators laid out their case at the IEEE Hot Chips conference in August.

Top notch series

Highlights

We may be close to rediscovering thousands of texts that had been lost for millennia. Their contents may reshape how we understand the Ancient World.

We don’t have original copies of anything, not of the Iliad, or the Aeneid, or Herodotus, or the Bible. Instead of originals, we find ourselves dealing with copies. These were first written on scrolls but later in books – the Romans called books codexes – starting in the first century AD. Did I say copies? That’s actually not correct either. We don’t have first copies of anything. What we do have is copies of copies, most of which date hundreds of years after the original was penned. Even many of our copies are not complete copies.

To most fully acclimate the reader to how tenuous this process is, this essay will focus on three different texts. The first will be a very well-known work that was never lost. Nevertheless, almost no one read it in earnest until the nineteenth century. I will then focus on a text that was lost to history, but that we were able to recover from the annals of time. Such examples are fortuitous. Our third example will be a text that we know existed, but of which we have no copies, and consider what important ramifications its discovery could hold. Finally, we’ll turn our attention again to the Villa of the Papyri and the gold mine of texts discovered there that new technologies are currently making available to classicists.

However, many of the scrolls from the Villa of the Papyri remain not only unread, but also unopened. This is because the eruption of Vesuvius left the scrolls carbonized, making it nearly impossible to open them. Despite this obstacle, Dr. Brent Seales pioneered a new technology in 2015 that allowed him and his team to read a scroll without opening it. The technique, using X-ray tomography and computer vision, is known as virtual unwrapping, and it was first used on one of the famous Dead Sea Scrolls, specifically the En-Gedi scroll, the earliest known copy of the Book of Leviticus (likely 210–390 CE). The X-rays allow scholars to create a virtual copy of the text that can then be read like any other ancient document by those with the proper language and paleography skills. Using Dr. Seales’s technique, scholars have been able to upload many of the texts online. A group of donors led by Nat Friedman and Daniel Gross have offered cash prizes to teams of classicists who can decipher the writings. The race to read the virtually unwrapped scrolls is known as the Vesuvius Challenge.

Highlights

When seawater gets cold, it gets viscous. This fact could explain how single-celled ocean creatures became multicellular when the planet was frozen during “Snowball Earth,” according to experiments.

A series of papers from the lab of Carl Simpson proposes an answer linked to a fundamental physical fact: As seawater gets colder, it gets more viscous, and therefore more difficult for very small organisms to navigate. Imagine swimming through honey rather than water. If microscopic organisms struggled to get enough food to survive under these conditions, as Simpson’s modeling work has implied, they would be placed under pressure to change — perhaps by developing ways to hang on to each other, form larger groups, and move through the water with greater force. Maybe some of these changes contributed to the beginning of multicellular animal life.

The experiment comes with a few caveats, and the paper has yet to be peer-reviewed; Simpson posted a preprint on biorxiv.org earlier this year. But it suggests that if Snowball Earth did act as a trigger for the evolution of complex life, it might be due to the physics of cold water.

It is difficult to precisely date when animals arose, but an estimate from molecular clocks — which use mutation rates to estimate the passage of time — suggests that the last common ancestor of multicellular animals emerged during the era known as the Sturtian Snowball Earth, sometime between 717 million and 660 million years ago. Large, unmistakably multicellular animals appear in the fossil record tens of millions of years after the Earth melted following another, shorter Snowball Earth period around 635 million years ago.

The paradox — a planet seemingly hostile to life giving evolution a major push — continued to perplex Simpson throughout his schooling and into his professional life. In 2018, as an assistant professor, he had an insight: As seawater gets colder, it grows thicker. It’s basic physics — the density and viscosity of water molecules rises as the temperature drops. Under the conditions of Snowball Earth, the ocean would have been twice or even four times as viscous as it was before the planet froze over.

As large creatures, we don’t think much about the thickness of the fluids around us. It’s not a part of our daily lived experience, and we are so big that viscosity doesn’t impinge on us very much. The ability to move easily — relatively speaking — is something we take for granted. From the time Simpson first realized that such limits on movement could be a monumental obstacle to microscopic life, he hasn’t been able to stop thinking about it. Viscosity may have mattered quite a lot in the origins of complex life, whenever that was.

“Putting this into our repertoire of thinking about why these things evolved — that is the value of the entire thing,” he said. “It doesn’t matter if it was Snowball Earth. It doesn’t matter if it happened before or after. Just the idea that it can happen, and happen quickly.”

Highlights

Amanda Randles wants to copy your body. If the computer scientist had her way, she’d have enough data — and processing power — to effectively clone you on her computer, run the clock forward, and see what your coronary arteries or red blood cells might do in a week. Fully personalized medical simulations, or “digital twins,” are still beyond our abilities, but Randles has pioneered computer models of blood flow over long durations that are already helping doctors noninvasively diagnose and treat diseases.

Her latest system takes 3D images of a patient’s blood vessels, then simulates and forecasts their expected fluid dynamics. Doctors who use the system can not only measure the usual stuff, like pulse and blood pressure, but also spy on the blood’s behavior inside the vessel. This lets them observe swirls in the bloodstream called vortices and the stresses felt by vessel walls — both of which are linked to heart disease. A decade ago, Randles’ team could simulate blood flow for only about 30 heartbeats, but today they can foresee over 700,000 heartbeats (about a week’s worth). And because their models are interactive, doctors can also predict what will happen if they take measures such as prescribing medicine or implanting a stent.

It’s a lot of data. We’re running simulations with up to 580 million red blood cells. There’s interactions with the fluid and red blood cells, the cells with each other, the cells with the walls — you’re trying to capture all of that. For each model, one time point might be half a terabyte, and there are millions of time steps in each heartbeat. It’s really computationally intense.

Fascinating, I like this kind of Magick.

This is interesting and potentially useful for anyone, who works in the corp which does not allow Linux laptops, but you can get your hands on Macs.

Highlights

So the point of the American UI system is not to make it easier to quit a job. But a few economists are now beginning to ask: Should it be?

A safety net program that would encourage more Americans to quit their jobs has generally been seen as a bad thing.

Boosting UI generosity doesn’t affect overall employment rates one way or the other. Instead of loafing around in subsidized unemployment, more generous benefits can support people to quit their jobs in search of better ones, which benefits workers through higher wages and better job satisfaction, and the economy through enhanced productivity as people find better uses for their skills.

The real losers would be lousy jobs, which would struggle to retain workers with a greater cushion to quit and go looking elsewhere.

A major barrier facing lasting reform has been that most people do not care about improving the unemployment system long enough to build the kind of political momentum that gets laws through Congress.

Without financial support, quitting in search of better work just isn’t always a viable option, especially for the more than one in 10 US households that have zero wealth to fall back on.

The unemployment insurance system was established during the Great Depression as part of the Social Security Act in 1935, when the unemployment rate was about 20 percent; helping those workers who still had jobs quit wasn’t exactly a policy priority. About half of American workers were excluded from coverage, including agricultural and domestic workers (many of whom were Black).

The surge of quits during the pandemic and the expansion of unemployment insurance created a unique dataset that caught the attention of economists Zhifeng Cai and Jonathan Heathcote.

After an extra $600 was added to weekly UI checks, along with a major expansion to who is eligible for the benefits, studies found no connection between the boosted UI and laziness or joblessness (echoing findings around unconditional cash transfers more broadly, where giving people cash doesn’t undermine their desire to work).

Economists have historically held equality and efficiency at odds with each other, with higher UI benefits seen as an equality booster that trades off against economic efficiency. But Cai explained in an interview with Vox that “if you give nothing to people who quit, it’s actually not an efficient choice, because there are too few people quitting. Our point is that even from an efficiency perspective, you still want to have some UI going to quitters.”

Looks fun!