Fly
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"Cancer is pretty lethal and we're not really good at fixing it yet, so when we find something that can really reduce the risk (and there aren't many - the only other ones I can think of are the magical substances known as not-smoking and avoiding-massive-doses-of-ionizing radiation), we should be all over that like cats on yarn."
Maintaining moderately high blood levels of vitamin D may reduce over all cancer rates by up to 30%. There is also evidence for green tea significantly reducing cancer rates.
Aspirin is an anti-coagulant so wounds take longer to stop bleeding. A surgeon will require that you stop taking aspirin long enough for the blood clotting factors... (read more)
Consider spermatogenesis as a model. There is a primary pool of slow dividing stem cells which are maintained in that state by local signaling from neighboring cells. In these stem cells, telomerase is sufficiently active that telomere length is preserved. The primary stem cell pool slowly replenishes a pool of fast dividing secondary stem cells in which telomerase is slightly less active. These are stem cells as the pool is largely self renewing. The secondary stem cell pool also generates progenitor cells which divide and differentiate to become sperm. Telomerase activity is much lower in these later cell generations so telomere length shortens with each division.
My speculation...
Bone marrow niches contain a common... (read 366 more words →)
Scientists have already demonstrated interventions that significantly extend maximum lifespan in several species. I see no reason to believe humans will be different.
My guess is that the primary cause of human aging is a combination of "depleted" stem cells combined with a gradual disruption of regulatory homeostasis. Part of the problem with "depleted" stem cells is an accumulation of silencing errors in the stem cell DNA. Another part is a gradual breakdown in local cell signaling that regulates cell fate. I believe both problems could be reversed by targeted "rebooting" of stem cell niches. I.e., inject new stem cells which have been engineered to stimulate tissue rejuvenation while also injecting growth factors... (read more)
This occurs all the time.
http://www.psychologicalscience.org/journals/pspi/pspi_8_2_article.pdf
In 2007, 160 gynecologists were provided with the relevant health statistics needed for calculating the chances that a woman with a positive mammogram test actually has cancer. The correct answer was about 10%. The majority of them grossly overestimated the probability of cancer, answering ‘‘90%’’ or ‘‘81%.’’
When most doctors are asked to interpret probabilistic lab results they suck. The doctors just don't think that way. Instead they have learned what to say so that the patient will immediately take the next recommended step, i.e., get a biopsy. From the doctor's perspective missing a cancer is a much worse outcome than needlessly worrying a patient. Their cached answer is "you have a high probability of cancer so a biopsy is needed immediately" which led to their guessing answers in the 80-90% range.
My gold standard for understanding reality is science, i.e., the process of collecting data, building models, making predictions, and testing those predictions again and again and again. In the spirit of "making beliefs pay rent" if Buddist meditation leads to less distorted views of reality then I would expect that "enlightened" Buddists would make especially successful scientists. As a religious group the Jews have been far more productive than the Buddists. Apparently Buddist physicists have no special advantage at building models that "carve reality at the joints". The Buddist monk may experience the illusion of knowing reality but actually understand less than a physicist. Or perhaps Buddist meditation trains the mind to... (read more)
Two other factors: 1) Population sub structure matters. Suppose a population of one million is divided into mating bands with 30 individuals. Small bands tend to lose diversity so some bands would have some of the minor alleles at higher frequency. Now suppose band X has minor alleles A1, A2, and A3 at high frequency while band Y has minor alleles A4, A5, and A6 at high frequency. The two bands meet and party. The result is kids with all 6 minor alleles. Those kids have big fitness advantage and those minor allele frequencies are significantly boosted in those bands. The high local concentration of those alleles means even more kids with... (read more)
"Why in the world should who the event happens to make a difference?"
I question the surface view of the world and the universe. E.g., I wouldn't be greatly surprised to discover that "I" am a character in a game. To the extent that I understand reality, my "evidence model" is centered on myself and diminishes as the distance from that center increases.
In the center I have my own memories combined with my direct sensory perception of my immediate environment. I also have my internal mental model of myself. This model helps me evaluate the reliability of my memories and thoughts. E.g., I know that my memory is less consistent than information that... (read more)
"all four dice were weighted"
I used three reddish, semi-transparent plastic dice with white dots (as I always did). My opponent used standard opaque, plastic ivory dice with black dots. I noticed nothing unusual about the dice and by the end of the run I was examining dice, cups, methods of rolling closely.
"Assume that a weighted die rolls the side that it favors with probability p, each of the sides adjacent to it with probability (1-p)/4, and never rolls the side opposite the favored side."
This assumption does not match my recollection of the dice rolls. As I stated previously, I rolled 6's, 5's, 4's, 3's, 2's, and 1's. I also never rolled a... (read more)
"the odds against you getting the exact sequence of outcomes you do get will be astronomical"
People notice and remember things they care about. Usually people care whether they win or lose, not the exact sequence of moves that produced the result. For an event to register as unusual a person must care about the outcome and recognize that the outcome is rare. The Risk game was special because I cared enough about the outcome to notice that I was losing, because the outcome (of losing) with 26 vs. 1 armies was incredibly unlikely, and because I could calculate the odds against such an outcome occurring due to chance.
"Eight different randomized controlled trials suggest you're wrong."
If the studies were done 20 years ago my guess is that the original trials were performed to see if aspirin reduced the risk of heart attacks. (At least that is what I recollect from that time period.) I doubt there were many people under 30 in those trials. I saw no indication in the linked article that ages were broken out so that one could determine whether people in their 20s who took aspirin for several years had less cancer 20 years later. Since few young people would be expected to get cancer I doubt the studies show that people in their 20s developed... (read more)