All posts by Max G. Levy

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About Max G. Levy

Science Journalist

An AI Finds Superbug-Killing Potential in Human Proteins

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WIRED

A team scoured the human proteome for antimicrobial molecules and found thousands, plus a surprise about how animals evolved to fight infections.

MARCELO DER TOROSSIAN Torres lifted the clear plastic cover off of a petri dish one morning last June. The dish, still warm from its sleepover in the incubator, smelled of rancid broth. Inside it sat a rubbery bed of amber-colored agar, and on that bed lay neat rows of pinpricks—dozens of colonies of drug-resistant bacteria sampled from the skin of a lab mouse.

Torres counted each pinprick softly to himself, then did some quick calculations. Untreated for the infection, the samples taken from an abscess on the mouse had yielded billions of superbugs, or antibiotic-resistant bacteria. But to his surprise, some of the other rows on the petri dish seemed empty. These were the ones corresponding to samples from mice that received an experimental treatment—a novel antibiotic.

Torres dug up other dishes cultured from more concentrated samples, taken from the same mice who had gotten the antibiotic. These didn’t look empty. When he counted them up, he found that the antibiotic had nuked the bacterial load so that it was up to a million times sparser than the sample from the untreated mouse. “I got very excited,” says Torres, a postdoc specializing in chemistry at the University of Pennsylvania. But this custom antibiotic wasn’t entirely his own recipe. It took an artificial intelligence algorithm scouring a database of human proteins to help Torres and his team find it.

Read the full story in WIRED.

Researchers Want to Restore ‘Good Noise’ in Older Brains

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WIRED

Aging people lose variation in brain oxygen levels—a sign of declining cognitive flexibility. A new drug study probes whether that loss can be reversed.

TO EAVESDROP ON a brain, one of the best tools neuroscientists have is the fMRI scan, which helps map blood flow, and therefore the spikes in oxygen that occur whenever a particular brain region is being used. It reveals a noisy world. Blood oxygen levels vary from moment to moment, but those spikes never totally flatten out. “Your brain, even resting, is not going to be completely silent,” says Poortata Lalwani, a PhD student in cognitive neuroscience at the University of Michigan. She imagines the brain, even at its most tranquil, as kind of like a tennis player waiting to return a serve: “He’s not going to be standing still. He’s going to be pacing a little bit, getting ready to hit the backhand.”

Read the full story in WIRED.

Timnit Gebru Says Artificial Intelligence Needs to Slow Down

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WIRED

The AI researcher, who left Google last year, says the incentives around AI research are all wrong.

ARTIFICIAL INTELLIGENCE RESEARCHERS are facing a problem of accountability: How do you try to ensure decisions are responsible when the decision maker is not a responsible person, but rather an algorithm? Right now, only a handful of people and organizations have the power—and resources—to automate decision-making.

Organizations rely on AI to approve a loan or shape a defendant’s sentence. But the foundations upon which these intelligent systems are built are susceptible to bias. Bias from the data, from the programmer, and from a powerful company’s bottom line can snowball into unintended consequences. This is the reality AI researcher Timnit Gebru cautioned against at a RE:WIRED talk on Tuesday.

“There were companies purporting [to assess] someone’s likelihood of determining a crime again,” Gebru said. “That was terrifying for me.”

Read the full story in WIRED.

From Chemist to Food-Tech CEO

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ACS ChemMatters Magazine

Aidan Mouat credits “dumb luck” for setting him on a path from chemist to CEO. Mouat has for the past six years run Hazel Technologies, which invented a small packet of chemicals to keep food fresh longer before reaching grocers.

If your store shelves are stocked year-round, you might wonder why these pouches are useful in the first place. What you don’t see is what gets thrown away. The reality is that the world produces “a colossal amount of food waste,” Mouat says. “We have a food system that is focused very heavily on production, instead of efficiency.” So, Mouat and his company co-founders devised a way to help prevent produce spoilage on its way from farm to store.

Read the full story in the December issue of ChemMatters

Climate-Driven Extinction Made Mammals’ Teeth Less Weird

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WIRED

Fossils show how species diversity—and dental diversity—suddenly collapsed 30 million years ago, suggesting a link between climate, diet, and survival.

DORIEN DE VRIES always asks for permission before flying across the world to touch someone else’s teeth. Some of the owners are anxious. Their teeth are fragile—irreplaceable. But de Vries, a paleontologist, sets their minds at ease. She knows how to be extra careful. “It’s exactly the same as dentists’,” she says of the gooey paste she uses to capture the tooth topography. “It sets really quickly and you can peel it off.” She casts the molds and then 3D-scans the replica teeth into digital immortality.

Well, maybe not exactly like a dentist. The teeth De Vries is working with are up to 56 million years old—they once belonged to the mammals of the late Eocene, Oligocene, and Miocene Epochs and are now preserved in museum and university collections.

Read the full story in WIRED.

Surprising Limits Discovered in Quest for Optimal Solutions

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Quanta Magazine

Algorithms that zero in on solutions to optimization problems are the beating heart of machine reasoning. New results reveal surprising limits.

Our lives are a succession of optimization problems. They occur when we search for the fastest route home from work or attempt to balance cost and quality on a trip to the store, or even when we decide how to spend limited free time before bed.

These scenarios and many others can be represented as a mathematical optimization problem. Making the best decisions is a matter of finding their optimal solutions. And for a world steeped in optimization, two recent results provide both good and bad news.

In a paper posted in August 2020, Amir Ali Ahmadi of Princeton University and his former student, Jeffrey Zhang, who is now at Carnegie Mellon University, established that for some quadratic optimization problems — in which pairs of variables can interact — it’s computationally infeasible to find even locally optimal solutions in a time-efficient manner.

But then, two days later, Zhang and Ahmadi released a second paper with a positive takeaway. They proved that it’s always possible to quickly identify whether a cubic polynomial — which can feature three-way interactions between variables — has a local minimum, and to find it if it does.

The limits are not what their discoverers expected.

Read the full story in Quanta Magazine

This Protein Predicts a Brain’s Future after Traumatic Injury

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WIRED

A blood test of “NfL” proteins answers questions about damage severity that doctors—and families—desperately need.

NEIL GRAHAM SEES a lot of head injuries: “Car accidents, violence, assault, gunshots, stabbing—the works, really,” says Graham, a neurologist from Imperial College London who practices at St. Mary’s Hospital nearby.

Doctors stop the bleeding, they relieve any pressure building inside the skull, maybe they’ll put the patient into a coma to keep the brain from overworking when it needs to relax and heal. Imaging can also help—to an extent. CT scans or MRIs pinpoint bruising or specks of hemorrhage in gray matter, the brain’s outer layer where neurons do most of their processing. But a clean scan isn’t a clean bill of health. Trauma to axons—a neuron’s root-like fibers that extend toward other neurons—often appears only in the deeper white matter, sometimes eluding simple scans.

Read the full story in WIRED.

The Artificial Leaf: Copying Nature to Fight Climate Change

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ACS ChemMatters Magazine

An ancient chemical process enabled Earth to become a lush place teeming with life. Now researchers are replicating this process in an attempt to slow global warming.

Every plant, animal, and person owes their life to one sequence of chemical reactions: photosynthesis. The process, which converts water and carbon dioxide into food using sunlight, first evolved in cyanobacteria more than 2 billion years ago.

That’s right. Plants weren’t the first organisms to develop photosynthesis, though they are better known for it. Cyanobacteria are the ones that originally filled the atmosphere with photosynthesis’s gaseous by-product, oxygen (O2), which set the stage for more diverse life on Earth.

As beneficiaries of photosynthesis, humans depend on plants in a sort of carbon seesaw. Plants take in CO2 and release O2. They store that carbon as sugar. Hanging vines, grass, and trees all grow by pulling carbon atoms out of the air. We do the reverse, taking in O2 and releasing CO2. Finally, everything we eat completes the handoff: Human eats plant (or the animal who already did), human exhales, plant stores carbon, and the cycle continues.

This seesaw is part of the much broader carbon cycle that has affected the radiation balance of our planet. Cutting down huge swaths of forests and the burning of carbon-based fossil fuels causes the levels of CO2, a major greenhouse gas, to rise. And plants on Earth along with other natural parts of the carbon cycle can’t restore the balance on their own.

But what if we could copy what plants do to grab some of that excess CO2 to make fuels sustainably, instead of relying so heavily on fossilized carbon?

Read the full story in the October 2021 issue of ChemMatters

The Long-Lost Tale of an 18th-Century Tsunami, as Told by Trees

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WIRED

Local evidence of the cataclysm has literally washed away over the years. But Oregon’s Douglas firs may have recorded clues deep in their tree rings.

ONE NIGHT IN late January 1700, two tectonic plates running along the Pacific Northwest coast released the tension they had accumulated during a centuries-long tête-à-tête. In a tectonic roar, the Juan de Fuca plate slipped past the North American plate, and a roughly 9.0-magnitude earthquake rattled the entire region. The coastline dropped and tsunamis washed over the entire Northwest coast.

Read the full story in WIRED

Dolphins Eavesdrop on Each Other to Avoid Awkward Run-Ins

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WIRED

The new finding underscores the complexity of marine mammals’ social life and cognition. It may also help save the snoopy cetaceans.

YOU’D THINK IT would be easier to spy on a Risso’s dolphin. The species frequents nearly every coast in the world. Their bulging heads and streaky gray and white patterning make them some of the most recognizable creatures in the ocean. And as with other cetaceans, they travel in groups and constantly chitchat: Clicks, buzzes, and whistles help them make sense of their underwater existence. Their social world is a sonic one.

“They’re a very vocal species,” says Charlotte Curé, a bioacoustics expert. “Sound is very important for them.”

Read the full story in WIRED