Sunday, May 1, 2022


Discovery! Breaking down plastics in days, not centuries

A group of scientists at the University of Texas at Austin have created a modified enzyme that can break down plastics that would otherwise take centuries to degrade in a matter of days.

The researchers, who [recently] published their findings in the peer-reviewed journal Nature, used machine learning to land on mutations to create a fast-acting protein that can break down building blocks of polyethylene terephthalate (PET), a synthetic resin used in fibers for clothing and plastic that, per the study, accounts for 12 percent of global waste. 

It does so through a process called depolymerization, in which a catalyst separates the building blocks that make up PET into their original monomers, which can then be repolymerized—built back into virgin plastic—and converted into other products. Most impressively, the enzymes broke down the plastic in one week. 

 “One thing we can do is we can break this down into its initial monomers,” Hal Alper, professor in Chemical Engineering and author on the paper, told Motherboard over the phone. “And that's what the enzyme does. And then once you have your original monomer, it’s as if you're making fresh plastic from scratch, with the benefit that you don't need to use additional petroleum resources.”

“This has advantages over traditional belt recycling,” Alper added. “If you were to melt the plastic and then remold it, you'd start to lose the integrity of the plastic each round that you go through with recycling. Versus here, if you're able to depolymerize and then chemically repolymerize, you can be making virgin PET plastic each and every time.” 

Their work adds to an existing line of query on plastic-eating enzymes, which were first recorded in 2005 and have since been followed by the discovery of 19 distinct enzymes, the paper notes. These are derived from naturally occurring bacteria that have been located living on plastic in the environment. 

But many of these naturally occurring enzymes are made up of permutations of proteins that function well in their specific environments, but are limited by temperature and pH conditions, and thus can’t be used in a wide range of settings, like across recycling centers, the authors argue. The enzyme Alper and his team discovered, by contrast, can break down 51 types of PET across a range of temperature and pH conditions. 

The researchers named the enzyme FAST-PETase, acronymic for “functional, active, stable, and tolerant PETase,” and they landed on its exact structure using machine learning. An algorithm was fed with 19,000 protein structures and taught to predict the positions of amino acids in a structure that are not optimized for their local environments. They also used the formula to rearrange amino acids from existing types of PETase into new positions, identified improved combinations and landed on one structure that saw 2.4 times more activity than an existing PETase enzyme at 40 degrees Celsius and 38 times more activity at 50 degrees Celsius.

It was then tested across a range of temperatures and pH conditions,and continued to outperform existing variants. 

 “What you see in nature is probably somewhat optimal, at least within the local environment around each and every one of those amino acids,” Alper said. “We can start looking at the protein of interest, and start going through each and every one of the amino acids in there and looking at its own microenvironment and seeing what fits and what doesn't fit.” 

 Alper and his team’s hope is that their enzyme will be more scalable than most, and will truly put PET-ase to the test of tackling the global plastics crisis. Already able to withstand a range of conditions, FAST-PETase must now prove that it can be both “portable and affordable at large industrial scale.”

First, Alper says, he and his team must test FAST-PETase on the wide range of different types of PET found in the waste stream, and the detritus that’s often found in plastic bottles or on top of plastic containers when it’s recycled. Should the researchers find an enzyme or group of enzymes with the robustness to be used practically, they believe it can help tackle the “billions of tons” of waste in our environment.

--Audrey Carleton, Vice

Why the GOP loves grumpy, middle-aged men

That seems to be the lesson, anyway, from a new focus group of eight such men convened by the New York Times to gauge their feelings on the state of the country, and of masculinity itself. There wasn't a lot of happiness in the group.

The guys grumbled about crime and cancel culture, and generally seemed to long for a better time when --there's no other way to put this--America was great. Nobody thought that racism or sexism is much of a problem in the 21st Century. They did think that men don't have it so great these days, though. One offered up action star Jason Statham as his model of masculinity.

Their complaints seemed at once half-formed and ancient. 

Danny, a 47-year-old realtor from Florida, complained about younger men "wearing very feminine clothes" with "tight skinny jeans, with no socks and velvet shoes." (Hilariously, another participant told Danny he was "a little too macho.") 

Christopher, a 51-year-old broker from Maryland, declared that feminists "are actually purveyors of men-bashing." 

And Robert, a 50-year-old infrastructure analyst from Texas, suggested the war in Ukraine was somehow the result of America's less-than-stout manliness.

"To me, the stuff that's going on with Ukraine--the United States hasn't filled our role as being masculine as a nation in that aspect," he said. "And that's why Putin is doing what he's doing, because when you don't step up into certain roles, then the stronger person is going to take over."

It's easy to make fun of some of this stuff, and on social media, lots of folks have. But let's try to take it seriously for a moment. Conservative men are unhappy? OK. What exactly are we supposed to do with that information? It's not really clear.

We probably shouldn't expect eight random individuals to come to the table with bullet-pointed policy ideas. But except for their problems with crime and traffic--there were a lot of traffic complaints--the group's frustrations seemed unfixable, the product of a deeply felt but inchoate sense that the culture has passed them by. That's old news. Conservatism is practically defined by its nostalgia for a time when men were men and America ruled the world, not to mention an obsession with movie star action heroes. We have always been at war with guys in skinny jeans and velvet shoes.

That which can't be fixed can be exploited, however. It's probably not a coincidence that Republican senators duck questions about their agenda while delivering speeches about the crisis of masculinity and waging war over Dr. Seuss books. The grumpiness of conservative men can't be solved and never will be. It will have to serve instead as an infinitely renewable political resource, a font of grievances fueling the Republican Party, forever and ever.

--Joel Mathis, The Week

10 David Foster Wallace quotes

1. “We’re all lonely for something we don’t know we’re lonely for. How else to explain the curious feeling that goes around feeling like missing somebody we’ve never even met?” 

2. “Lonely people tend, rather, to be lonely because they decline to bear the psychic costs of being around other humans. They are allergic to people. People affect them too strongly.” 

3. “It’s a very American illness, the idea of giving yourself away entirely to the idea of working in order to achieve some sort of brass ring that usually involves people feeling some way about you—I mean, people wonder why we walk around feeling alienated and lonely and stressed out

4. “Fiction is one of the few experiences where loneliness can be both confronted and relieved. Drugs, movies where stuff blows up, loud parties—all these chase away loneliness by making me forget my name’s Dave and I live in a one-by-one box of bone no other party can penetrate or know. Fiction, poetry, music, really deep serious sex, and, in various ways, religion—these are the places (for me) where loneliness is countenanced, stared down, transfigured, treated.” 

5. “The interesting thing is why we’re so desperate for this anesthetic against loneliness.” 

6. “Fiction’s about what it is to be a human being.” 

7. “Good fiction’s job is to comfort the disturbed and disturb the comfortable.” 

8. “There’s a kind of Ah-ha! Somebody at least for a moment feels about something or sees something the way that I do. It doesn’t happen all the time. It’s these brief flashes or flames, but I get that sometimes. I feel unalone—intellectually, emotionally, spiritually. I feel human and unalone and that I’m in a deep, significant conversation with another consciousness in fiction and poetry in a way that I don’t with other art.” 

9. “We all suffer alone in the real world. True empathy’s impossible. But if a piece of fiction can allow us imaginatively to identify with a character’s pain, we might then also more easily conceive of others identifying with their own. This is nourishing, redemptive; we become less alone inside. It might just be that simple.” 

10. “Sarcasm and jokes were often the bottle in which clinical depressives sent out their most plangent screams for someone to care and help them.” 

Regrettable rules of high-tech happenstance

1.  The likelihood that any digital device will fail is directly proportional to your need for that device to work properly.  
2. Your laptop will wait to die until just after your warranty for the system has expired.  The encouraging news is that taking out an extended warranty of one year will likely extend your machine's life by exactly that length of time.
3.  Voice mail messages always break up and become unintelligible just as the caller is leaving his or her call-back number.  Note that this rule applies only to important calls that you absolutely need to return.
4.  "While supplies last" is a synonym for "until the guy right in front of you buys the last one."
5.  You know the next great version with all the features you really want?  It won't be released until right after you've bought the previous version. (And if you decide to wait for that next great version, it will be delayed.  Probably for a long time.  Or maybe forever.)

--Steve Fox, PC World magazine

Coloring inside the lines

I wrote a play, "Picasso at the Lapin Agile," about a conversation between Picasso and Einstein. There's a scene with an art dealer, and he's waxing rhapsodic about a painting, and he says, "You know what makes this painting great? The frame. It forces a containment, and the painter has to work within the boundaries. They have to innovate within." I like that [about bluegrass]. Here's what you've got, now what you can do with it?  

--Steve Martin

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