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Diabetes reversal in Tennessee

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Apparently it’s catching on. Blake Farmer reports for NPR:

Chains, saws and old logging equipment litter the back field of Wendy Norris’ family farm, near the county seat of Altamont, Tenn. Norris used to be part of the local timber industry, and the rusted tools are relics from a time when health woes didn’t hold her back from felling hardwoods.

“I was nine months pregnant,” Norris says. “Me and my husband stayed about 10 or 15 miles in the middle of nowhere, in a tent, for a long time.”

Those outdoor adventures are just a memory now. A few years ago, as Norris turned 40, her feet started going numb. She first assumed it was from standing all day at her job at a nursing home.

“But it wasn’t,” she recalls now. “It was that neuropathy, where my [blood] sugar was high and I didn’t know it.” Norris had developed Type 2 diabetes.

Grundy County, Tenn., has a long list of public health challenges, and Type 2 diabetes tops the list. The county is stunningly scenic; it also has one of the lowest life expectancy rates in the region.

Norris was relatively active. She also enjoyed sodas, sweets and frozen dinners. Meanwhile, diabetes runs in her family. So, when her diabetes diagnosis came down, her doctor prescribed insulin shots and told her to watch what she ate.

“You’re sitting there thinking, ‘Well, what does that mean?’ ” Norris says.

Type 2 diabetes can be reversed with weight loss and exercise; but research shows that people need lots of help to achieve control of blood sugar with just a change in diet and lifestyle, and they rarely get enough support. It’s easier for doctors and patients to rely primarily on medication.

Norris says trying to overhaul her diet by herself was confusing and difficult. And when things didn’t change, the doctor just kept increasing her dosage of insulin.

But then Norris lost her health insurance. The injectable insulin cost her hundreds of dollars a month — money she simply didn’t have.

Fortunately, that’s when a couple of nurses who were members of her community stepped in to help — not with cash, but with crucial support of a different sort.

At the nonprofit Beersheba Springs Medical Clinic, a nonprofit clinic founded in 2010 to bring free or low-cost health care to the area, Norris was introduced to an alternative approach to taming her Type 2 diabetes — and the prospect of reversing her diagnosis altogether.

Retired nurses on a mission

In a former parsonage near the clinic, Karen Wickham ladles out lentil stew as a handful of participants in the evening’s health education session arrive.

She and her husband, Steve, are white-haired, semiretired nurses who have dedicated their lives to what they call “diabetes reversal.” They offer six-week seminars to Type 2 patients like Norris, who has also brought along her father and daughter.

“It’s our purpose,” Karen says. “Our purpose in life is to try to help make a difference — first in our community.”

With slide presentations, the Wickhams explain the difference between sucrose and glucose and the science behind the fact that foods like potatoes spike blood sugar, while sweet potatoes don’t. They preach eating as much fiber as a stomach can stand and dropping almost every kind of sweetened beverage.

Then they demonstrate ways to burn all those calories. On one evening, Steve invents the “Beersheba Boogie” on the spot, asking participants to raise their knees and pump their fists in place. . .

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Written by LeisureGuy

22 July 2019 at 5:44 pm

Quantum Darwinism, an Idea to Explain Objective Reality, Passes First Tests

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Darwin’s insight seems to have been much deeper than we knew: it’s a look into the heart of how nature works. Philip Ball writes in Quanta:

It’s not surprising that quantum physics has a reputation for being weird and counterintuitive. The world we’re living in sure doesn’t feel quantum mechanical. And until the 20th century, everyone assumed that the classical laws of physics devised by Isaac Newton and others — according to which objects have well-defined positions and properties at all times — would work at every scale. But Max Planck, Albert Einstein, Niels Bohr and their contemporaries discovered that down among atoms and subatomic particles, this concreteness dissolves into a soup of possibilities. An atom typically can’t be assigned a definite position, for example — we can merely calculate the probability of finding it in various places. The vexing question then becomes: How do quantum probabilities coalesce into the sharp focus of the classical world?

Physicists sometimes talk about this changeover as the “quantum-classical transition.” But in fact there’s no reason to think that the large and the small have fundamentally different rules, or that there’s a sudden switch between them. Over the past several decades, researchers have achieved a greater understanding of how quantum mechanics inevitably becomes classical mechanics through an interaction between a particle or other microscopic system and its surrounding environment.

One of the most remarkable ideas in this theoretical framework is that the definite properties of objects that we associate with classical physics — position and speed, say — are selected from a menu of quantum possibilities in a process loosely analogous to natural selection in evolution: The properties that survive are in some sense the “fittest.” As in natural selection, the survivors are those that make the most copies of themselves. This means that many independent observers can make measurements of a quantum system and agree on the outcome — a hallmark of classical behavior.

This idea, called quantum Darwinism (QD), explains a lot about why we experience the world the way we do rather than in the peculiar way it manifests at the scale of atoms and fundamental particles. Although aspects of the puzzle remain unresolved, QD helps heal the apparent rift between quantum and classical physics.

Only recently, however, has quantum Darwinism been put to the experimental test. Three research groups, working independently in Italy, China and Germany, have looked for the telltale signature of the natural selection process by which information about a quantum system gets repeatedly imprinted on various controlled environments. These tests are rudimentary, and experts say there’s still much more to be done before we can feel sure that QD provides the right picture of how our concrete reality condenses from the multiple options that quantum mechanics offers. Yet so far, the theory checks out.

Survival of the Fittest

At the heart of quantum Darwinism is the slippery notion of measurement — the process of making an observation. In classical physics, what you see is simply how things are. You observe a tennis ball traveling at 200 kilometers per hour because that’s its speed. What more is there to say?

In quantum physics that’s no longer true. It’s not at all obvious what the formal mathematical procedures of quantum mechanics say about “how things are” in a quantum object; they’re just a prescription telling us what we might see if we make a measurement. Take, for example, the way a quantum particle can have a range of possible states, known as a “superposition.” This doesn’t really mean it is in several states at once; rather, it means that if we make a measurement we will see one of those outcomes. Before the measurement, the various superposed states interfere with one another in a wavelike manner, producing outcomes with higher or lower probabilities.

But why can’t we see a quantum superposition? Why can’t all possibilities for the state of a particle survive right up to the human scale?

The answer often given is that superpositions are fragile, easily disrupted when a delicate quantum system is buffeted by its noisy environment. But that’s not quite right. When any two quantum objects interact, they get “entangled” with each other, entering a shared quantum state in which the possibilities for their properties are interdependent. So say an atom is put into a superposition of two possible states for the quantum property called spin: “up” and “down.” Now the atom is released into the air, where it collides with an air molecule and becomes entangled with it. The two are now in a joint superposition. If the atom is spin-up, then the air molecule might be pushed one way, while, if the atom is spin-down, the air molecule goes another way — and these two possibilities coexist. As the particles experience yet more collisions with other air molecules, the entanglement spreads, and the superposition initially specific to the atom becomes ever more diffuse. The atom’s superposed states no longer interfere coherently with one another because they are now entangled with other states in the surrounding environment — including, perhaps, some large measuring instrument. To that measuring device, it looks as though the atom’s superposition has vanished and been replaced by a menu of possible classical-like outcomes that no longer interfere with one another.

This process by which “quantumness” disappears into the environment is called decoherence. It’s a crucial part of the quantum-classical transition, explaining why quantum behavior becomes hard to see in large systems with many interacting particles. The process happens extremely fast. If a typical dust grain floating in the air were put into a quantum superposition of two different physical locations separated by about the width of the grain itself, collisions with air molecules would cause decoherence — making the superposition undetectable — in about 10−31 seconds. Even in a vacuum, light photons would trigger such decoherence very quickly: You couldn’t look at the grain without destroying its superposition.

Surprisingly, although decoherence is a straightforward consequence of quantum mechanics, it was only identified in the 1970s, by the late German physicist Heinz-Dieter Zeh. The Polish-American physicist Wojciech Zurek further developed the idea in the early 1980s and made it better known, and there is now good experimental support for it.

But to explain the emergence of objective, classical reality, it’s not enough to say that decoherence washes away quantum behavior and thereby makes it appear classical to an observer. Somehow, it’s possible for multiple observers to agree about the properties of quantum systems. Zurek, who works at Los Alamos National Laboratory in New Mexico, argues that two things must therefore be true.

First, quantum systems must have states that are especially robust in the face of disruptive decoherence by the environment. Zurek calls these “pointer states,” because they can be encoded in the possible states of a pointer on the dial of a measuring instrument. A particular location of a particle, for instance, or its speed, the value of its quantum spin, or its polarization direction can be registered as the position of a pointer on a measuring device. Zurek argues that classical behavior — the existence of well-defined, stable, objective properties — is possible only because pointer states of quantum objects exist.

What’s special mathematically about pointer states is that the decoherence-inducing interactions with the environment don’t scramble them: Either the pointer state is preserved, or it is simply transformed into a state that looks nearly identical. This implies that the environment doesn’t squash quantumness indiscriminately but selects some states while trashing others. A particle’s position is resilient to decoherence, for example. Superpositions of different locations, however, are not pointer states: Interactions with the environment decohere them into localized pointer states, so that only one can be observed. Zurek described this “environment-induced superselection” of pointer states in the 1980s.

But there’s a second condition that a quantum property must meet to be observed. Although immunity to interaction with the environment assures the stability of a pointer state, we still have to get at the information about it somehow. We can do that only if it gets imprinted in the object’s environment. When you see an object, for example, that information is delivered to your retina by the photons scattering off it. They carry information to you in the form of a partial replica of certain aspects of the object, saying something about its position, shape and color. Lots of replicas are needed if many observers are to agree on a measured value — a hallmark of classicality. Thus, as Zurek argued in the 2000s, our ability to observe some property depends not only on whether it is selected as a pointer state, but also on how substantial a footprint it makes in the environment. The states that are best at creating replicas in the environment — the “fittest,” you might say — are the only ones accessible to measurement. That’s why Zurek calls the idea quantum Darwinism.

It turns out that the same stability property that promotes environment-induced superselection of pointer states also promotes quantum Darwinian fitness, or the capacity to generate replicas. “The environment, through its monitoring efforts, decoheres systems,” Zurek said, “and the very same process that is responsible for decoherence should inscribe multiple copies of the information in the environment.”

Information Overload

It doesn’t matter, of course, whether information about a quantum system that gets imprinted in the environment is actually read out by a human observer; all that matters for classical behavior to emerge is that the information get there so that it could be read out in principle. “A system doesn’t have to be under study in any formal sense” to become classical, said Jess Riedel, a physicist at the Perimeter Institute for Theoretical Physics in Waterloo, Canada, and a proponent of quantum Darwinism. “QD putatively explains, or helps to explain, all of classicality, including everyday macroscopic objects that aren’t in a laboratory, or that existed before there were any humans.”

About a decade ago, . . .

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Written by LeisureGuy

22 July 2019 at 12:26 pm

Posted in Evolution, Science

The Economist Who Would Fix the American Dream

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Gareth Cook writes in the Atlantic:

Raj Chetty got his biggest break before his life began. His mother, Anbu, grew up in Tamil Nadu, a tropical state at the southern tip of the Indian subcontinent. Anbu showed the greatest academic potential of her five siblings, but her future was constrained by custom. Although Anbu’s father encouraged her scholarly inclinations, there were no colleges in the area, and sending his daughter away for an education would have been unseemly.

But as Anbu approached the end of high school, a minor miracle redirected her life. A local tycoon, himself the father of a bright daughter, decided to open a women’s college, housed in his elegant residence. Anbu was admitted to the inaugural class of 30 young women, learning English in the spacious courtyard under a thatched roof and traveling in the early mornings by bus to a nearby college to run chemistry experiments or dissect frogs’ hearts before the men arrived. Anbu excelled, and so began a rapid upward trajectory. She enrolled in medical school. “Why,” her father was asked, “do you send her there?” Among their Chettiar caste, husbands commonly worked abroad for years at a time, sending back money, while wives were left to raise the children. What use would a medical degree be to a stay-at-home mother?

In 1962, Anbu married Veerappa Chetty, a brilliant man from Tamil Nadu whose mother and grandmother had sometimes eaten less food so there would be more for him. Anbu became a doctor and supported her husband while he earned a doctorate in economics. By 1979, when Raj was born in New Delhi, his mother was a pediatrics professor and his father was an economics professor who had served as an adviser to Prime Minister Indira Gandhi.

When Chetty was 9, his family moved to the United States, and he began a climb nearly as dramatic as that of his parents. He was the valedictorian of his high-school class, then graduated in just three years from Harvard University, where he went on to earn a doctorate in economics and, at age 28, was among the youngest faculty members in the university’s history to be offered tenure. In 2012, he was awarded the MacArthur genius grant. The following year, he was given the John Bates Clark Medal, awarded to the most promising economist under 40. (He was 33 at the time.) In 2015, Stanford University hired him away. Last summer, Harvard lured him back to launch his own research and policy institute, with funding from the Bill & Melinda Gates Foundation and the Chan Zuckerberg Initiative.

Chetty turns 40 this month, and is widely considered to be one of the most influential social scientists of his generation. “The question with Raj,” says Harvard’s Edward Glaeser, one of the country’s leading urban economists, “is notif he will win a Nobel Prize, but when.”

The work that has brought Chetty such fame is an echo of his family’s history. He has pioneered an approach that uses newly available sources of government data to show how American families fare across generations, revealing striking patterns of upward mobility and stagnation. In one early study, he showed that children born in 1940 had a 90 percent chance of earning more than their parents, but for children born four decades later, that chance had fallen to 50 percent, a toss of a coin.

In 2013, Chetty released a colorful map of the United States, showing the surprising degree to which people’s financial prospects depend on where they happen to grow up. In Salt Lake City, a person born to a family in the bottom fifth of household income had a 10.8 percent chance of reaching the top fifth. In Milwaukee, the odds were less than half that.

Since then, each of his studies has become a front-page media event (“Chetty bombs,” one collaborator calls them) that combines awe—millions of data points, vivid infographics, a countrywide lens—with shock. This may not be the America you’d like to imagine, the statistics testify, but it’s what we’ve allowed America to become. Dozens of the nation’s elite colleges have more children of the 1 percent than from families in the bottom 60 percent of family income. A black boy born to a wealthy family is more than twice as likely to end up poor as a white boy from a wealthy family. Chetty has established Big Data as a moral force in the American debate.Now he wants to do more than change our understanding of America—he wants to change America itself. His new Harvard-based institute, called Opportunity Insights, is explicitly aimed at applying his findings in cities around the country and demonstrating that social scientists, despite a discouraging track record, are able to fix the problems they articulate in journals. His staff includes an eight-person policy team, which is building partnerships with Charlotte, Seattle, Detroit, Minneapolis, and other cities.

For a man who has done so much to document the country’s failings, Chetty is curiously optimistic. He has the confidence of a scientist: If a phenomenon like upward mobility can be measured with enough precision, then it can be understood; if it can be understood, then it can be manipulated. “The big-picture goal,” Chetty told me, “is to revive the American dream.”

Last summer, I visited Opportunity Insights on its opening day. The offices are housed on the second floor of a brick building, above a café and across Massachusetts Avenue from Harvard’s columned Widener Library. Chetty arrived in econ-casual: a lilac dress shirt, no jacket, black slacks. He is tall and trim, with an untroubled air; he smiled as he greeted two of his longtime collaborators—the Brown University economist John Friedman and Harvard’s Nathaniel Hendren. They walked him around, showing off the finished space, done in a modern palette of white, wood, and aluminum with accent walls of yellow and sage.

Later, after Chetty and his colleagues had finished giving a day of seminars to their new staff, I caught up with him in his office, which was outfitted with a pristine whiteboard, an adjustable-height desk, and a Herman Miller chair that still had the tags attached. The first time I’d met him, at an economics conference, he had told me he was one of several cousins on his mother’s side who go by Raj, all named after their grandfather, Nadarajan, all with sharp minds and the same long legs and easy gait. Yet of Nadarajan’s children, only Chetty’s mother graduated from college, and he’s certain that this fact shaped his generation’s possibilities. He was able to come to the United States as a child and attend an elite private school, the University School of Milwaukee. New York Raj—the family appends a location to keep them straight—came to the U.S. later in life, at age 28, worked in drugstores, and then took a series of jobs with the City of New York. Singapore Raj found a job in a temple there that allows him to support his family back in India, but means they must live apart. Karaikudi Raj, named for the town where his mother grew up, committed suicide as a teenager.

I asked Boston Raj to consider what might have become of him if that wealthy Indian businessman had not decided, in the precise year his mother was finishing high school, to create a college for the talented women of southeastern Tamil Nadu. “I would likely not be here,” he said, thinking for a moment. “To put it another way: Who are all the people who are not here, who would have been here if they’d had the opportunities? That is a really good question.”

Charlotte is one of America’s great urban success stories. In the 1970s, it was a modest-size city left behind as the textile industry that had defined North Carolina moved overseas. But in the 1980s, the “Queen City” began to lift itself up. US Airways established a hub at the Charlotte Douglas International Airport, and the region became a major transportation and distribution center. Bank of America built its headquarters there, and today Charlotte is in a dead heat with San Francisco to be the nation’s second-largest banking center, after New York. New skyscrapers have sprouted downtown, and the city boundary has been expanding, replacing farmland with spacious homes and Whole Foods stores. In the past four decades, Charlotte’s population has nearly tripled.

Charlotte has also stood out in Chetty’s research, though not in a good way. In a 2014 analysis of the country’s 50 largest metropolitan areas, Charlotte ranked last in ability to lift up poor children. Only 4.4 percent of Charlotte’s kids moved from the bottom quintile of household income to the top. Kids born into low-income families earned just $26,000 a year, on average, as adults—perched on the poverty line. “It was shocking,” says Brian Collier, an executive vice president of the Foundation for the Carolinas, which is working with Opportunity Insights. “The Charlotte story is that we are a meritocracy, that if you come here and are smart and motivated, you will have every opportunity to achieve greatness.” The city’s true story, Chetty’s data showed, is of selective opportunity: All the data-scientist and business-development-analyst jobs in the thriving banking sector are a boon for out-of-towners and the progeny of the well-to-do, but to grow up poor in Charlotte is largely to remain poor.

To help cities like Charlotte, Chetty takes inspiration from medicine. For thousands of years, he explained, little progress was made in understanding disease, until technologies like the microscope gave scientists novel ways to understand biology, and thus the pathologies that make people ill. In October, Chetty’s institute released an interactive map of the United States called the Opportunity Atlas, revealing the terrain of opportunity down to the level of individual neighborhoods. This, he says, will be his microscope.

Drawing on anonymized government data over a three-decade span, the researchers linked children to the parents who claimed them as dependents. The atlas then followed poor kids from every census tract in the country, showing how much they went on to earn as adults. The colors on the atlas reveal a generation’s prospects: red for areas where kids fared the worst; shades of orange, yellow, and green for middling locales; and blue for spots like Salt Lake City’s Foothill neighborhood, where upward mobility is strongest. It can also track children born into higher income brackets, compare results by race and gender, and zoom out to show states, regions, or the country as a whole.

The Opportunity Atlas has a fractal quality. Some regions of the United States  . . .

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Written by LeisureGuy

21 July 2019 at 11:47 am

How the sugar industry manipulated science

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Written by LeisureGuy

21 July 2019 at 7:58 am

Prebiotics: Tending our inner garden

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Evolution produces some clever mechanisms, but if the environment changes, they can stop working.

Written by LeisureGuy

19 July 2019 at 2:06 pm

Interesting sugar comparison

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This is a screengrab from this video. I thought it was interesting enough to pull out. Fill disclosure: I avoid sugar, but after watching the video, I think I’m open to using date sugar.

 

Written by LeisureGuy

18 July 2019 at 8:29 pm

E.P.A. Won’t Ban Chlorpyrifos, Pesticide Tied to Children’s Health Problems

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The attitude seems to be “Who cares about kids? They don’t vote and they don’t have much money.” Lisa Friedman reports in the NY Times:

The Environmental Protection Agency on Thursday announced it would not ban a widely used pesticide associated with developmental disabilities and other health problems in children.

The decision not to prohibit the use of the pesticide, chlorpyrifos, comes after years of legal wrangling. It represents a victory for the chemical industry and farmers who have lobbied to continue using the substance, arguing it is necessary to protect crops.

In making its ruling, the E.P.A. rejected claims that the amount of pesticide residue allowed to remain in or on treated foods was unsafe, and said that the science was unsettled.

“E.P.A. has determined that their objections must be denied because the data available are not sufficiently valid, complete or reliable to meet petitioners’ burden to present evidence demonstrating that the tolerances are not safe,” the agency said in a statement.

The agency added that it would continue to review the safety of chlorpyrifos through 2022.

The product, sold under the commercial name Lorsban, has already been banned for household use but remains in widespread use by farmers for more than 50 fruit, nut, cereal and vegetable crops.

The Obama administration decided to ban chlorpyrifos in 2015 after scientific studies produced by the E.P.A. showed the pesticide had the potential to damage brain development in children. But in 2017 Scott Pruitt, then the administrator of the E.P.A., reversed that prohibition, setting off a new round of legal challenges.

Patti Goldman, an attorney for Earthjustice, an environmental group that brought a legal challenge against the E.P.A.’s 2017 decision on behalf of farmworker organizations and others, criticized the decision.

“By allowing chlorpyrifos to stay in our fruits and vegetables, Trump’s E.P.A. is breaking the law and neglecting the overwhelming scientific evidence that this pesticide harms children’s brains,” Ms. Goldman said in a statement. . .

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The Trump administration is an on-going disaster.

Written by LeisureGuy

18 July 2019 at 2:19 pm

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