Tag Archives: Tech

For AI to Know What Something Is, It Must Know What Something Isn’t

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Quanta Magazine

Today’s language models are more sophisticated than ever, but challenges with negation persist.

Nora Kassner suspected her computer wasn’t as smart as people thought. In October 2018, Google released a language model algorithm called BERT, which Kassner, a researcher in the same field, quickly loaded on her laptop. It was Google’s first language model that was self-taught on a massive volume of online data. Like her peers, Kassner was impressed that BERT could complete users’ sentences and answer simple questions. It seemed as if the large language model (LLM) could read text like a human (or better).

But Kassner, at the time a graduate student at Ludwig Maximilian University of Munich, remained skeptical. She felt LLMs should understand what their answers mean — and what they don’t mean. It’s one thing to know that a bird can fly. “A model should automatically also know that the negated statement — ‘a bird cannot fly’ — is false,” she said. But when she and her adviser, Hinrich Schütze, tested BERT and two other LLMs in 2019, they found that the models behaved as if words like “not” were invisible.

Read the full story in Quanta Magazine

Everyone Was Wrong About Reverse Osmosis—Until Now

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WIRED

A new paper showing how water actually travels through a plastic membrane could make desalination more efficient. That’s good news for a thirsty world.

MENACHEM ELIMELECH NEVER made peace with reverse osmosis. Elimelech, who founded Yale’s environmental engineering program, is something of a rock star among those who develop filtration systems that turn seawater or wastewater into clean drinking water. And reverse osmosis is a rock star among filter technologies: It has dominated how the world desalinates seawater for about a quarter of a century. Yet nobody really knew how it worked. And Elimelech hated that.

Read the full story in WIRED

Fighting Climate Change One Meal at a Time

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CHEMMATTERS

Beth Zotter can talk about anything. The problems she encounters as chief executive officer (CEO) of a food company named Umaro are very specific. But the main focus is algae—which Zotter’s Umaro Foods claims is the future of abundant, sustainable protein—and its mission is to save our planet from climate calamity.

Read the full story in ChemMatters April Issue

From Pond Scum to Product: The Chemistry of Algae

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CHEMMATTERS

The first time Beth Zotter tried her company’s bacon, it tasted bitter, and powdery. “Most protein concentrates don’t taste very well,” says Zotter, cofounder and chief executive officer of Umaro Foods. Umaro was attempting to re-create crispy, savory bacon out of seaweed.

Why bacon? “It’s America’s favorite food,” said co-founder Amanda Stiles on an episode of the TV show, “Shark Tank,” where the two raised funds for Umaro. “It’s the holy grail of plant-based meat. Sizzling, salty, delicious.” But the real magic of Umaro’s pitch was not the bacon. It was the algae.

Read the full story in ChemMatters April Issue

This Lab-Grown Skin Could Revolutionize Transplants

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WIRED

A new kind of “edgeless” engineered tissue can fit any irregular shape, paving the way for hand and face grafts that look and move better.

ALBERTO PAPPALARDO WAS nervous the morning before the transplant. He’d spent the previous month nurturing a cluster of skin cells until they reached their final form: a pinkish-white tissue in the shape of a mouse’s hindlimb that could be slipped onto the animal like a pant leg. If all went according to plan, the mouse’s surrounding skin would accept the lab-grown stuff as its own.

In the end, it took less than 30 seconds to position the new skin, and under 10 minutes to complete the whole procedure. “It was a perfect fit,” recalls Pappalardo, a medical doctor and postdoc focusing on dermatology and tissue engineering at Columbia University Medical Center. That’s a big deal, because it could help solve a persistent challenge in treating burns and other large wounds: how to cover irregular shapes with real, functional skin.

Read the full story in WIRED

This Fake Skin Fools Mosquitoes With Real Blood

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WIRED

Research on new repellents and the viruses these insects carry relies on lab animals and human volunteers. What if there was a better option?

THE WORLD’S DEADLIEST animal is a picky eater. Because they transmit viral diseases like Zika and chikungunya, and the parasites that cause malaria, mosquitoes like blood-sucking Aedes aegypti are responsible for over 700,000 deaths worldwide every year.

But in Omid Veiseh’s lab at Rice University, his team of bioengineers was struggling to get mosquitoes to eat. Typically, researchers study mosquitoe feeding by letting them bite live animals—lab mice, or grad students and postdocs who offer up their arms for science. That’s not ideal, because lab animals can be expensive and impractical to work with, and their use can raise ethical issues. Student arms don’t scale well for large tests.

In collaboration with entomologists from Tulane University, the Rice team wanted to develop a way of studying mosquito behavior without the challenges of experimenting on large numbers of animals. Their solution was something totally different: real blood encased in a lifeless hydrogel. “It feels like jello,” Veiseh says. “The mosquitoes have to bite through the jello to get to the blood.” 

Read the full story in WIRED

Machines Learn Better if We Teach Them the Basics

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QUANTA MAGAZINE

A wave of research improves reinforcement learning algorithms by pre-training them as if they were human.

Imagine that your neighbor calls to ask a favor: Could you please feed their pet rabbit some carrot slices? Easy enough, you’d think. You can imagine their kitchen, even if you’ve never been there — carrots in a fridge, a drawer holding various knives. It’s abstract knowledge: You don’t know what your neighbor’s carrots and knives look like exactly, but you won’t take a spoon to a cucumber.

Artificial intelligence programs can’t compete. What seems to you like an easy task is a huge undertaking for current algorithms.

Read the full story in Quanta Magazine

Physicists Controlled Lightning with Lasers on a Mountaintop

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INVERSE

The car-sized laser can shoot up to 1,000 pulses per second.

LAST YEAR MARKED the 270th anniversary of Benjamin Franklin’s lightning rod — but it’s more than a relic of history. The Franklin rod remains in use today because the simple design exploits some powerful physics: A tall metal rod lures in lightning and chunky wires dissipate the storm’s energy into the earth, sparing humans and surrounding structures.

But thanks to recent physics breakthroughs, a wild new technology could end the rod’s lightning safety monopoly.

Read the full story in Inverse

How the physics of farts could help prevent an outbreak

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INVERSE

Meet the S.H.A.R.T. machine, a device helping AI analyze toilet activities.

AS DAVID ANCALLE opened video after video of diarrhea this year, it struck him: This is not what he expected to be doing for his Ph.D.

Ancalle, a mechanical engineering student at Georgia Tech who researches fluid dynamics, is currently working to demystify the acoustics of urination, flatulence, and diarrhea. His team is training AI to recognize and analyze the sound of each bathroom phenomenon; in fact, research suggests that tracking the flow of our excretions could benefit public health.

Read the full story in Inverse