Skip to main content

Home/ TOK@ISPrague/ Group items tagged DNA

Rss Feed Group items tagged

Lawrence Hrubes

I Had My DNA Picture Taken, With Varying Results - NYTimes.com - 0 views

  •  
    "So I decided to read the tea leaves of my DNA. I reasoned that it was worth learning painful information if it might help me avert future illness. Like others, I turned to genetic testing, but I wondered if I could trust the nascent field to give me reliable results. In recent years, a handful of studies have found substantial variations in the risks for common diseases predicted by direct-to-consumer companies. I set out to test the tests: Could three of them agree on me? The answers were eye-opening"
Lawrence Hrubes

Scientists Unveil New 'Tree of Life' - The New York Times - 1 views

  • A team of scientists unveiled a new tree of life on Monday, a diagram outlining the evolution of all living things. The researchers found that bacteria make up most of life’s branches.
  • In his 1859 book “On the Origin of Species,” Charles Darwin envisioned evolution like a branching tree.
  • In the 1970s, Carl Woese of the University of Illinois and his colleagues published the first “universal tree of life” based on this approach. They presented the tree as three great trunks.
  • ...1 more annotation...
  • Patrick Forterre, an evolutionary biologist at the Pasteur Institute in France, agreed that bacteria probably make up much of life’s diversity. But he had concerns about how Dr. Banfield and her colleague built their tree. He argued that genomes assembled from DNA fragments could actually be chimeras, made up of genes from different species. “It’s a real problem,” he said.
Lawrence Hrubes

Same but Different - The New Yorker - 0 views

  • Why are identical twins alike? In the late nineteen-seventies, a team of scientists in Minnesota set out to determine how much these similarities arose from genes, rather than environments—from “nature,” rather than “nurture.” Scouring thousands of adoption records and news clips, the researchers gleaned a rare cohort of fifty-six identical twins who had been separated at birth. Reared in different families and different cities, often in vastly dissimilar circumstances, these twins shared only their genomes. Yet on tests designed to measure personality, attitudes, temperaments, and anxieties, they converged astonishingly. Social and political attitudes were powerfully correlated: liberals clustered with liberals, and orthodoxy was twinned with orthodoxy. The same went for religiosity (or its absence), even for the ability to be transported by an aesthetic experience. Two brothers, separated by geographic and economic continents, might be brought to tears by the same Chopin nocturne, as if responding to some subtle, common chord struck by their genomes.
  • It’s one thing to study epigenetic changes across the life of a single organism, or down a line of cells. The more tantalizing question is whether epigenetic messages can, like genes, cross from parents to their offspring.
  • The most suggestive evidence for such transgenerational transmission may come from a macabre human experiment. In September, 1944, amid the most vengeful phase of the Second World War, German troops occupying the Netherlands banned the export of food and coal to its northern parts. Acute famine followed, called the Hongerwinter—the hunger winter. Tens of thousands of men, women, and children died of malnourishment; millions suffered it and survived. Not surprisingly, the children who endured the Hongerwinter experienced chronic health issues. In the nineteen-eighties, however, a curious pattern emerged: when the children born to women who were pregnant during the famine grew up, they had higher rates of morbidity as well—including obesity, diabetes, and mental illness. (Malnourishment in utero can cause the body to sequester higher amounts of fat in order to protect itself from caloric loss.) Methylation alterations were also seen in regions of their DNA associated with growth and development. But the oddest result didn’t emerge for another generation. A decade ago, when the grandchildren of men and women exposed to the famine were studied, they, too, were reported to have had higher rates of illness. (These findings have been challenged, and research into this cohort continues.) “Genes cannot change in an entire population in just two generations,” Allis said. “But some memory of metabolic stress could have become heritable.”
markfrankel18

4 | The Golden Ratio: Design's Biggest Myth | Co.Design | business + design - 0 views

  • The golden ratio's aesthetic bona fides are an urban legend, a myth, a design unicorn. Many designers don't use it, and if they do, they vastly discount its importance. There's also no science to really back it up.
  • "Strictly speaking, it's impossible for anything in the real-world to fall into the golden ratio, because it's an irrational number," says Keith Devlin, a professor of mathematics at Stanford University.
  • You Don't Really Prefer The Golden Ratio In the real world, people don't necessarily prefer the golden ratio.
  • ...1 more annotation...
  • "We're creatures who are genetically programmed to see patterns and to seek meaning," he says. It's not in our DNA to be comfortable with arbitrary things like aesthetics, so we try to back them up with our often limited grasp of math. But most people don't really understand math, or how even a simple formula like the golden ratio applies to complex system, so we can't error-check ourselves.
markfrankel18

Why Police Lineups Will Never Be Perfect - The Atlantic - 0 views

  • Eyewitness testimony is hugely influential in criminal cases. And yet, brain research has shown again and again that human memory is unreliable: Every time a memory is recalled it becomes vulnerable to change. Confirming feedback—such as a detective telling a witness she “did great”—seems to distort memories, making them feel more accurate with each recollection. Since the start of the Innocence Project 318 cases have been overturned thanks to DNA testing. Eyewitness mistakes played a part in nearly three-quarters of them.
Lawrence Hrubes

My Great-Great-Aunt Discovered Francium. And It Killed Her. - NYTimes.com - 0 views

  • There is a common narrative in science of the tragic genius who suffers for a great reward, and the tale of Curie, who died from exposure to radiation as a result of her pioneering work, is one of the most famous. There is a sense of grandeur in the idea that paying heavily is a means of advancing knowledge. But in truth, you can’t control what it is that you find — whether you’ve sacrificed your health for it, or simply years of your time.
  • How quickly an element decayed and how it did so — meaning which of its component parts it shed — became the focus of researchers in radioactivity. Apart from purely scientific insights, there was a hope that radiation could lead to something marvelous. X-rays, a kind of radiation discovered by Wilhelm Roentgen and produced by accelerated electrons, had already been hailed as a major medical breakthrough and, in addition to showing doctors their patients’ insides, were being investigated as a treatment for skin lesions from tuberculosis and lupus. In her 1904 book “Investigations on Radioactive Substances,” Marie Curie wrote that radium had promise, too — diseased skin exposed to it later regrew in a healthy state. Radium’s curious ability to destroy tissue was being turned against cancer, with doctors sewing capsules of radium into the surgical wounds of cancer patients (including Henrietta Lacks, whose cells are used today in research). This enthusiasm for radioactivity was not confined to the doctor’s office. The element was in face creams, tonics, even candy. According to the Encyclopaedia Britannica article that Curie and her daughter wrote on radium in 1926, preliminary experiments suggested that radium could even improve the quality of soil.
  • Perhaps the most tragic demonstration of this involved workers at the United States Radium Corporation factory in Orange, N.J., which in 1917 began hiring young women to paint watch faces with glow-in-the-dark radium paint. The workers were told that the paint was harmless and were encouraged to lick the paintbrushes to make them pointy enough to inscribe small numbers. In the years that followed, the women began to suffer ghoulish physical deterioration. Their jaws melted and ballooned into masses of tumors larger than fists, and cancers riddled their bodies. They developed anemia and necrosis. The sensational court case started — and won — by the dying Radium Girls, as they were called, is a landmark in the history of occupational health. It was settled in June 1928, four months before Marguerite Perey arrived at the Radium Institute to begin a 30-year career of heavy exposure to radiation.
  • ...2 more annotations...
  • We know now that alpha and beta particles emitted in radiation attack DNA and that the mutations they cause can lead to cancer. Ingested radioactive elements can concentrate in the bones, where they continue their decay, in effect poisoning someone for as long as that person lives. By the time Perey made her discovery, she was already heavily contaminated. She spent the last 15 years of her life in treatment for a gruesome bone cancer that spread throughout her body, claiming her eyesight, pieces of her hand and most of the years in which she had planned to study francium. As the disease progressed, she warned her students of the horrible consequences of radiation exposure. Francis, my grandfather, says he recalls hearing that when she walked into labs with radiation counters in her later years, they would go off.
  • Over the years, historians have pondered what drove the Curies to throw caution so thoroughly to the wind. Perhaps it was inconceivable to them that the benefits of their research would not outweigh the risks to themselves and their employees. In a field in which groundbreaking discoveries were being made and the competition might arrive there first, speed was put above other concerns, Rona noted. But you almost get the impression that in the Curie lab, dedication to science was demonstrated by a willingness to poison yourself — as if what made a person’s research meaningful were the sacrifices made in the effort to learn something new.
Lawrence Hrubes

Should a Sibling Be Told She's Adopted? - The New York Times - 0 views

  • My sister is the greatest blessing in my life. My parents and I were at the hospital when her birth mother went into labor, so she has been with us for her entire life. My parents never told her that she was adopted, and they asked me not to say anything. They planned on telling her when she was old enough to understand, but they kept putting it off. They know that I believe they have done her a serious disservice.
  • I think she suspects she’s different. She asks me sometimes why she’s so much shorter than the rest of us, for example. I do my best to deflect her questions, but it hurts every time. My sister and I are very close, and we see each other often. Keeping this lie feels like a giant burden, but, at this point, I don’t know that it would do her any good to know the truth. She was recently diagnosed with bipolar disorder and has been working hard to keep her life balanced. Finding out now that she’s adopted could throw her into a depression. I fear, however, that with the mail-in DNA tests available these days, or should a medical emergency arise, she’ll find out the truth and she won’t forgive me.
1 - 10 of 10
Showing 20 items per page