Arete
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physics of a motorbike collision - why it is so hazardous?
Arete replied to Linker's topic in Classical Physics
I had a pretty bad crash on a motorbike when I was 19. A lady backed out of a garage right in front of me (She was running late for work, apparently), and I hit the side of the car doing about 70km/h. I was wearing a helmet, gloves, boots and riding pants. Injury 1. As I pitched over the bike, my knee contacted the fairing or the side of the car and hyper-extended, rupturing my ACL and MCL, and tearing my meniscus. Injury 2. I flew over the car and put my hand out as I hit the ground. I broke both my right radius and ulna, both of which protruded out the end of my elbow. I also managed to break a scaphoid in my left wrist. Having both arms in casts is about as much fun as you'd expect, especially with a blown knee. Injury 3. The biggie - I landed on the top of my head and hyper-extended my neck. I suffered a hangman's fracture to my C2 vertebrae. Got lucky not to be dead. In comparison with a car, a motorbike has little to no passive protection for the rider. No crumple zones, airbags, seat belts, head restraints, padded interior, etc. This means that in a crash, your body comes in contact with hard and sharp surfaces, like the road, car panels, poles, etc. In a car, there are many features designed to isolate a driver from hard objects, and to increase deceleration times. On a bike, you have none of these, so the injuries you potentially sustain are likely to be more severe. I also managed to be in a multiple rollover accident in a car as a passenger, and walked and walked away with minor cuts and bruises - my body never came in contact with a hard surface, like the pavement and the structure around me deformed and absorbed a lot of the force. -
As already pointed out to you, the frequency, severity and duration of heatwaves are predicted to increase in response to global warming. "Model results for areas of Europe and North America, associated with the severe heat waves in Chicago in 1995 and Paris in 2003, show that future heat waves in these areas will become more intense, more frequent, and longer lasting in the second half of the 21st century." http://www.sciencema.../5686/994.short Please stop ignoring evidence that is provided, or refute it with actual evidence if you wish to argue against it. Doing so, as you are leads to a circular discussion.
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Again, do you have anything to support the assertion you're making? If you actually read beyond the single sentence of the paper quoted, the simulation is using current mortality rates and do not take into account future changes in human behavior that would reduce mortality due to heat waves, as future developments which reduce mortality - such as medical advances are difficult or impossible to predict. This means that for your assertion about jumpers to have any merit whatsoever, you'll need to establish that people currently die during heat waves due to not removing jumpers, and that removal of jumpers in the future is likely to have a significant effect on mortality during heat waves. If you are unable, it seems reasonable to assume that you are making up nonsensical retorts on the spot in an attempt to justify an a priori position, rather than approaching any of the evidence in good faith.
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So you don't haven anything other than your own personal incredulity to support your ridiculous argument that mortality during heat waves is caused by people not removing their jumpers?
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I'll repeat what I asked you in the relevant thread - do you have anything other than your own personal incredulity to support your statement? You are contradicting published science: "A significantly raised risk of heat-related and cold-related mortality was observed in all regions. The elderly were most at risk. In the absence of any adaptation of the population, heat-related deaths would be expected to rise by around 257% by the 2050s from a current annual baseline of around 2000 deaths, and cold-related mortality would decline by 2% from a baseline of around 41 000 deaths. " http://jech.bmj.com/...13-202449.short So an actual reasoned response rather than insults and personal incredulity are required. In your first response to that paper, you simply got the maths completely wrong.... now you've presented equally ridiculous reasoning to reject its results. I mean, are you really trying to say that at risk people die during heat waves because they don't "take their jumpers off"? It's a patently incorrect and supremely ignorant argument. If you have to attempt to reject the vast body of literature and medical records on the association between heat waves and mortality to try and build and argument, it would appear that if anyone is being deliberately misleading here, it would be you. http://www.biomedcentral.com/content/pdf/1476-069X-9-37.pdf http://www.sciencedirect.com/science/article/pii/S0378512211000806
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What makes you attracted to a certain look? I think I know the answer...
Arete replied to ADVANCE's topic in Speculations
Scientifically speaking, among a multitude of other factors, humans tend to be attracted to potential mates with MHC genes which differ to their own through olfactory ques, thus producing MHC heterozygous offspring with a higher likelihood of disease resistance. http://www.plosgenetics.org/article/info%3Adoi%2F10.1371%2Fjournal.pgen.1000184 -
Creation vs. Evolution - Need Help!
Arete replied to Skoobuh's topic in Evolution, Morphology and Exobiology
As this topic has arisen many times, this is a copypasta I posted in another thread on the topic: - We have direct observational evidence, like the Lenski experiment which has evolved E. coli populations for 25 years and shown how through evolutionary processes, they can develop new phenotypic traits. We also have instances where a population of organisms has diverged into two species during historical tiime, like the apple maggot fly and the yellow fever mosquito. - We have biogeographical evidence that organisms share common ancestry. For example, many of the organisms which are found on the former continents which made up Gondwana are more related to each other than the places they are near to now, providing evidence of common ancestry. - We have macro-morphological evidence, like vestigial organs like tail bones in humans and leg bones in whales, which support common ancestry with animals with tails and legs, respectively. - On the cellular level, the evidence for common ancestry becomes even more compelling. Despite the obvious differences between say an dandelion and a horse, when you look at the the structural components of the cells, they are largely the same. This suggests that, despite the massive differences in external morphology you see today, they share common ancestry. - Prehaps the most elegant (or maybe I'm just biased by working in genetics) evidence comes from genetics. All organisms on earth share the same basic structure and code for their blueprint. The study of genetics provides a comprehensive understanding of the mechanism by which phenotypic traits are inherited, how they can change, and provide the co-ordinates required to map the evolution of life. This is not an exhaustive list of the lines of evidence we have for evolution - but when you "overlay" each of these "jigsaws" with each other, you can put together a more complete picture of the overall evidence, and the image we get is overwhelmingly consistent with evolutionary theory. As we look more, get more pieces of each puzzle, learn how to reshuffle the pieces we have more accurately, we get a better overall picture, and it only keeps looking more and more like evolution is the right fit for the data. As an ending, I don't believe that evolutionary theory is exclusive of religion - it would seem that the Pope strongly agrees, calling the argument "absurd". You can believe in evolution and God - I have had the pleasure of collaborating with Professor Francisco Ayala who is a former Dominican Priest, a Professor of Evolutionary Biology at UC Irvine and former president of the AAAS. You might find some of his essays on religion and science interesting, especially, his book - "Am I a monkey?" which addresses the question of what evolution is and whether it is compatible with belief in God. http://www.washingtonpost.com/wp-dyn/content/article/2010/04/26/AR2010042603381.html http://www.faculty.uci.edu/profile.cfm?faculty_id=2134 -
To put it in context - a relatively small overdose of acteominophen will cause irreversible liver damage and potentially lead to an un-treatable, horrible death from liver failure. In fact, acteominophen is the major cause of acute liver failure in the western world. Yet, you can buy a bottle of 1000 pills of it off the shelf in the supermarket. http://en.wikipedia.org/wiki/Paracetamol#Adverse_effects http://www.staples.com/Acetaminophen-Extra-Strength-Caplets-1000-Caplets-Bottle/product_114896 On the other hand, as previously shown, the risk of suicide due to SSRI side effects is statistically non-significant, or at least is unclear and difficult to detect. Unlike acteominophen, SSRI's are prescription drugs only obtainable from a doctor. You're substantially overplaying the risks of SSRI medications and not acknowledging the substantial benefits they can have for sufferers of depression, anxiety, OCD and eating disorders.
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Your liberal use of sweeping generalizations, unsupported assertions and leading questions suggests that you might not be approaching discussion in good faith. In addition, all drugs have side effects and virtually any condition can be misdiagnosed. You could pretty much use you logic to argue against the use of any treatment for any condition. A meta analysis of over 400 studies evaluating elevated suicide risk associated with SSRI use found no elevated risk of suicide, and only a slight increase in the risk of non-suicidal self harm. http://www.bmj.com/content/330/7488/385 So the risk of suicide is negligible. Let's examine efficacy - SSRI's significantly reduce the symptoms of moderate and severe depression, with less side effects in most patients than TCA's. http://cat.inist.fr/aModele=afficheN&cpsidt=1835031 According to the evidence, the limited risk and high efficacy of SSRIs most likely make their prescription for the conditions they are designed to treat worth it.
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"A man's ethical behavior should be based effectually on sympathy, education, and social ties and needs; no religious basis is necessary. Man would indeed be in a poor way if he had to be restrained by fear of punishment and hope of reward after death." Albert Einstein
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Carrots are alive. Plants respond to painful stimuli too http://www.pri.org/stories/2014-01-09/new-research-plant-intelligence-may-forever-change-how-you-think-about-plants Also, stone fruits contain cyanide, tomatoes and potatoes contain solanine, broccoli, apples, onions, oranges, strawberries, lemons and mushrooms all contain acetaldehyde, a natural by-product of oxidation and a known human carcinogen... etc etc. Your argument could be spun against almost any food product consumable by humans.
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Will I be able to pursue my own research in college?
Arete replied to Unity+'s topic in Science Education
I have a couple of undergraduate students (including a computer science major) doing research projects over the summer, and generally have a couple of senior thesis students working with me throughout the year. It depends on what you mean by "independent" research. Will you be able to pursue your own research funding, set up your own lab and do whatever you want? Probably not. Can you take on a project under the guidance of an adviser, and take care of the day to day research tasks to develop it yourself? Probably. There's probably some sort of undergraduate research program set up already in your department, although it might take seeking out a potential adviser yourself, then figuring out what funding opportunities there are for it, and obtaining them. As for time management for undergrads - I always advise them to treat college like a 9-5 job. During that time, if you aren't in a class, read materials and do assignments. If you do, you will almost never have to do any work on the weekends or in the evenings. Is it what I did? nope. Is it what most students do? Hell no. "I've got 4 hours off in the middle of a Tuesday, let's go do something fun!" is part of the college experience, provided you aren't doing it every break. -
To use an old saying - it's good to have an open mind, but don't open it so far that your brain falls out. While imagination and creativity are essential components of science, those new ideas should build on existing knowledge rather than rejecting or ignoring it. If something in a movie blatantly contradicts everything we know about a subject, maintaining the idea that it is somehow plausible just because imagination, is somewhat fruitless.
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Why women are so extremely emotional?
Arete replied to Linker's topic in Evolution, Morphology and Exobiology
I will let a bunch of seventh grade students explain via the medium of rap why the opinion of female scientists you're displaying here is pure idiocy. -
Why women are so extremely emotional?
Arete replied to Linker's topic in Evolution, Morphology and Exobiology
Your personal experiences are anecdotes, influenced by your personal biases. Do you have any actual evidence - as in a quantifiable measure of differential emotional response to stimuli? Searching for a molecular mechanism for a trait is; a) intrinsically linked to the evolutionary processes by which the trait came about, and b) reliant on the trait being objectively quantifiable. Neglecting evolution and simply assuming the trait is there due to anecdotal experience is unlikely to yield a sensible explanation. -
"the high warming scenario will degrade 9–15% of the top 3 metres of permafrost by 2040, increasing to 47–61% by 2100 and 67–79% by 2300 (these ranges are the 95% confidence intervals around the group's mean estimate). " http://www.nature.com/nature/journal/v480/n7375/full/480032a.html It would be extremely beneficial to discussion if you could substantiate the many assertions you are making.
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There's a whole class of other psychoactive molecules in cannabis - i.e. cannabinoids: "The major differences between the cannabinoids are determined by the extent to which they are psychologically active. Three classes of cannabinoids, the CBG, CBC and CBD are not known to have such an effect. THC, CBN, CBDL and some other cannabinoids on the other hand are known to be psychologically active to varying degrees." http://adai.uw.edu/marijuana/factsheets/cannabinoids.htm http://www.news-medical.net/health/Cannabinoids-What-are-Cannabinoids.aspx http://en.wikipedia.org/wiki/Cannabinoid
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Reasons not to worry (Climate change debate)
Arete replied to Tim the plumber's topic in Climate Science
Do you seriously have nothing aside from personal incredulity to support your argument? -
Good thing no one is claiming it then. In fact: "Recent climatic changes have enhanced plant growth in northern mid-latitudes and high latitudes." http://www.sciencemag.org/content/300/5625/1560.short
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Reasons not to worry (Climate change debate)
Arete replied to Tim the plumber's topic in Climate Science
Rather than restating your own unsupported personal opinion, could you explain why these studies are "drivel", please? "The 2003 heat wave, by mimicking quite closely the possible course of summers in the latter part of the 21st century, can thus be used within certain limits as an analog to what may occur with more regularity in the future. The physical processes that characterized the 2003 heat wave, such as soil moisture depletion and the positive feedback on summer temperatures, and the lack of convective rainfall in many parts of the continent that generally occur from June–September, are projected to occur with greater frequency in the future." http://onlinelibrary.wiley.com/doi/10.1029/2003GL018857/full "Using a threshold for mean summer temperature that was exceeded in 2003, but in no other year since the start of the instrumental record in 1851, we estimate it is very likely (confidence level >90%)9 that human influence has at least doubled the risk of a heatwave exceeding this threshold magnitude." http://www.nature.com/nature/journal/v432/n7017/abs/nature03089.html "Model results for areas of Europe and North America, associated with the severe heat waves in Chicago in 1995 and Paris in 2003, show that future heat waves in these areas will become more intense, more frequent, and longer lasting in the second half of the 21st century." http://www.sciencemag.org/content/305/5686/994.short Verbatim from the study you quoted: "This conclusion differs somewhat from the result of a recent reconstruction of Arctic summer air temperature over the past 2000 years, which indicates that a long cooling trend over the last 2000 years ended with a pronounced warming during the twentieth century [Kaufman et al., 2009]. Possible reasons for the differences are numerous, and include at a minimum 1) our record is a mean‐annual temperature, not a summer temperature, and variability is minimal in summer but highest in winter [box, 2002]; 2) differences between air and snow temperature may be influenced by changes in cloud cover and wind speed, which affect the strength of the near‐surface inversion; and 3) our site is not necessarily representative of the whole Arctic, and may respond in opposite ways to annular mode fluctuations." So you may want to take a little of your own advice: -
a) viruses and bacteria are distinct entities. As such, HIV doesn't create bacteria when it enters a cell, it replicates HIV viruses. b) HIV virus actually replicates within CD4, T cells, microglia and macrophages - which are types of white blood/immune cells, it uses these cells to replicate itself, then kills them by bursting them open to spread itself throughout the body. By killing immune cells, the virus depletes the body's immune systems and limits its ability to respond to the viral infection. c) The immune system can actually recognize and kill HIV, and usually a person will get flu like symptoms immediately after an infection of HIV. However, the virus is able to "hide" from the immune system after this initial response. We don't 100% understand how it does this, but it is thought that it somehow prevents HLA binding - which allows immune cells to identify and kill infected cells. d) So while the virus is able to escape detection, it's also killing off the body's immune system, making it harder for the body to find and kill viruses outside of cells. http://www.mcb.uct.ac.za/cann/335/McMichael/McMichael.html Hope that helps a little.
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Reasons not to worry (Climate change debate)
Arete replied to Tim the plumber's topic in Climate Science
a) Link works fine for me. b) http://en.wikipedia.org/wiki/Snowmelt Snow accumulates, then melts when the weather gets warm. This creates the influx of spring time water known as snow-melt. Water falling as rain does not accumulate and runs off immediately, resulting in lower spring and summer flow levels, increased glacier recession, lower groundwater tables, Salmon declines and reduced hydroelectric output. http://www.ecy.wa.gov/climatechange/reducedsnow_more.htm Could you please provide some form of support for this statement? As you've demonstrated an inability to do basic arithmetic, it's extraordinarily difficult to take your personal assessment of the accuracy of climate models seriously. I'd really like to see some sort of analysis to demonstrate their ineffectiveness rather than simply an anonymous person on an internet forum who said so and has since been demonstrated to be unable to math. While your assertion that the data is flawed goes unsupported by actual analysis, we're left with only personal incredulity and ad hominem to support your argument. As such, please provide a reference, or a specific analysis demonstrating that the model is incorrect, or I'm going to assume you are just making things up as you go along to suit your point of view. This statement is entirely incorrect: a) Ocean temperatures have increased http://www.epa.gov/climatechange/science/indicators/oceans/sea-surface-temp.html b) Coral bleaching is not localized and is increasing in ALL major coral reef systems. http://www.globalissues.org/article/173/coral-reefs c) Large scale bleaching events are correlated with abnormally high ocean surface temperatures. http://www.wcs.org/news-and-features-main/aceh-coral-bleaching.aspx d) Other causes are being investigated. http://www.sciencemag.org/content/301/5635/929.short Again the link works fine and links the WHO 2002 World Health Report, from which the excerpt is taken. If your browser is malfunctioning I'm sure Google will find it for you. a)The "in the last 500 years" is indicative of that being when reliable records started, unless you can provide evidence that there was an anomalous weather event then? b) I agree, they happen normally. No one ever said they didn't. The prediction is that they will become more frequent due to the impacts of greenhouse emissions. c) You're the one claiming that there's nothing to worry about. There's a clear demonstration that if heat waves become more frequent, mortality due to heatwaves will increase. Either you don't care about more people dying, or there is something to worry about. I suggest you revise your basic arithmetic, as you're - you guessed it, comprehensively wrong. Let's work it through like we're in primary school, shall we? 2,000 people currently die each year due to heat. This will increase by 257%. 41,000 people currently die each year due to cold. This will decrease 2% Current total for both hot and cold combined: 2,000 + 41,000 = 43,000 Predicted changes: deaths due to hot weather: 2,000 x 2.57 = 5,140 deaths due to cold weather:41,000 x 0.02 = -820 Predicted total of future mortality: (2,000 + 5,140) + (41,000 - 820) = 7,140 + 40,180 = 47,320 Predicted total deaths - Current total deaths: 47,320 - 43,000 = an increase in mortality of 4,320 people per year. When you can't do basic mathematics, it's hard to take your unsupported claims about climate models being "garbage" with even an ounce of seriousness. Now you're rejecting documented events in recent history? Wow - okay. http://www.cnn.com/2004/TECH/science/08/02/heatwave.europe/ You do understand how that makes your argument look right? I mean, do you really want to lower discussion of climate change to the level of holocaust denial, or the anti vaccine movement? Cause we're rapildy approaching that point. -
Reasons not to worry (Climate change debate)
Arete replied to Tim the plumber's topic in Climate Science
That's one of the most comprehensively wrong posts I've seen in my time on this forum: 1. Snowpack is not equatable to precipitation. http://meteora.ucsd.edu/cap/pdffiles/CA_climate_Scenarios.pdf these are the timing and phase of precipation resulting in an ecological pattern of spring thaw. 2. Most models do not predict any addtional rainfall in the Sierra Nevadas http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0024465#pone-0024465-g004 "These results are bad news because stronger storms are far more dangerous than weaker ones. A 2005 study that examined hurricane impacts from 1900 to 2005 found that Category 4 and 5 storms accounted for only 6% of U.S. landfalls, but caused 48% of all hurricane damage. Using this study as a starting point, and accounting for the projected mix of more bigger storms and fewer smaller ones, Knutson's team estimated that by 2100, the overall destructive potential of hurricanes may increase by 30%." http://www.pbs.org/wgbh/nova/earth/hurricanes-climate.html "The patterns are characterized by drying over most of Africa, southeast Asia, eastern Australia and southern Europe from 1950 to 2010" http://www.nature.com/nclimate/journal/v3/n1/full/nclimate1633.html "Using an ensemble of 35 simulations, we show a likely increase in the global severity of drought by the end of 21st century, with regional hotspots including South America and Central and Western Europe in which the frequency of drought increases by more than 20%." http://www.pnas.org/content/early/2013/12/12/1222473110.short "coral reefs worldwide are in serious decline" http://www.nature.com/nature/journal/v429/n6994/full/nature02691.html Up to 43% coral die off due to heat stress induced bleaching in the Andaman Islands of Indonesia in 2005 http://eprints.cmfri.org.in/9419/ And French Polynesia http://eprints.cmfri.org.in/9419/ Thailand http://link.springer.com/article/10.1007/s00338-012-1005-x etc. "The study indicates that the climatic changes that have occurred since the mid-1970s could already be causing over 150,000 deaths and approximately five million 'disability-adjusted life years' (DALYs) per year" http://www.who.int/whr/2002/en/ "The summer of 2003 was probably Europe's hottest summer in over 500 years, with average temperatures 3.5 °C above normal6, 7, 8. With approximately 22,000 to 45,000 heat-related deaths occurring across Europe over two weeks in August 2003 (refs 9 and 10), this is the most striking recent example of health risks directly resulting from temperature change ... heatwaves in Chicago and Paris will be 25% and 31% more frequent, respectively, by 2090 and that the average length of a heatwave in Paris will have increased from 8–13 days to 11–17 days. Large increases in heatwaves were also projected for the western and southern USA and the Mediterranean region59"http://www.nature.com/nature/journal/v438/n7066/full/nature04188.html#B56 As for the hot is better than cold: "A significantly raised risk of heat-related and cold-related mortality was observed in all regions. The elderly were most at risk. In the absence of any adaptation of the population, heat-related deaths would be expected to rise by around 257% by the 2050s from a current annual baseline of around 2000 deaths, and cold-related mortality would decline by 2% from a baseline of around 41 000 deaths. " http://jech.bmj.com/content/early/2014/01/08/jech-2013-202449.short So, in a simulation study of the UK, 5, 140 more people die due to increades temperatures, 820 less die due to fewer cold temperatures. Not if you continue with your fantastic impression of an ostrich, and make up the data that suits your point of view.