SGU Episode 377
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| SGU Episode 377 |
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| 8th Oct 2012 |
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| (brief caption for the episode icon) |
| Skeptical Rogues |
| S: Steven Novella |
B: Bob Novella |
R: Rebecca Watson |
J: Jay Novella |
E: Evan Bernstein |
| Quote of the Week |
For my part, whatever anguish of spirit it may cost, I am willing to know the whole truth; to know the worst and provide for it. |
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| Download Podcast |
| SGU Podcast archive |
| Forum Discussion |
Introduction
You're listening to the Skeptics' Guide to the Universe, your escape to reality.
This Day in Skepticism (1:20)
- October 5 1945: Curse of the billy goat placed on Chicago Cubs
News Items
The Physics of Roulette (4:22)
Vitamin D and the Common Cold (14:28)
S: All right, well, the next news item is about another vitamin that doesn't help with common colds.
J: Is this – is this vitamin D we're talking about?
B: Yeah, vitamin D, oh man.
E: Delta.
S: Yeah, so I guess D is after C in the alphabet, right? So –
E: Last time I checked.
S: Yeah,vitamin C doesn't work for common colds and now we're on to vitamin D doesn't work for common colds either.
E: Guess what's next?
S: (chuckles)
J: Washing your hands, that's – there's a vitamin wash. There you go.
S: There are actually very good reasons to suspect that vitamin D supplements may be helpful for a number of respiratory conditions: chronic obstructive pulmonary disease, COPD; or asthma, or even upper respiratory infections. Vitamin D classically is important for bone homeostatis and bone health, calcium regulation, but it's been found that it also is an important cofactor in certain aspects of the immune system for certain proteins in the immune system and vitamin D deficiency could impair immune system function. So therefore, it stands to reason that supplementing may be beneficial. The existing research was, however, recently reviewed, and it showed that there is no current evidence that just routinely taking vitamin D decreases the risk of getting a cold or the duration of getting and there was the largest study conducted to date. So this was 161 people in the vitamin D group; 161 in the control group; it was double-blind, placebo-controlled, and they followed subjects for 18 months, over an 18-month period. The vitamin D group had no advantage over the placebo group; both groups got about 3.7 colds per person over that period of time. 3.7 in the vitamin D group; 3.8 in the placebo group, so no statistically significant difference.
E: Steve, what do you think of these numbers: 161 people, 18 months. Are we talking a large enough sample size?
S: That's reasonable; I mean, the rule of thumb is 50 people in each arm is a reasonably powered study for most ef– it depends on the effect size you're looking for, but for a clinically relevant moderate effect size – rule of thumb, 50 people in each group is – is good. So this is 161 in each group; it's not a massive study, but it's perfectly reasonable; large enough, certainly, to have detected a clinically relevant effect. Obviously, you can't rule out a tiny effect; that would be too small to measure with that many people, but that's probably not clinically relevant either. This is probably not the last word on vitamin D and all respiratory effect because there is some reasonable plausibility here. There is some preliminary evidence to suggest that maybe it is helpful with COPD, for example. One big question in all of this research is: Does supplementing vitamin D only with those who are vitamin D deficient or insufficient, or will it also help with people who have a normal level of vitamin D to begin with? Probably, it seems that, if there is a beneficial effect, it's probably limited to those people who are low in vitamin D. Many people, their vitamin D levels do dip in the winter because we have less sunlight exposure and that's also when the flu's going around and kids are in school and passing germs around and people get more colds. Taking a vitamin D supplement to prevent the dip in your vitamin D levels over the winter is not unreasonable. But certainly this study shows that it's not – obviously a panacea; it's not helpful taking – taken routinely. One criticism of this study was that this was conducted in New Zealand and New Zealand gets more sunlight during their winter than maybe other parts of the world, and so the question is: do the results of this study extrapolate to–
E: To the Northern Hemisphere?
S: Yeah, parts of the world, or just farther away from the equator in either direction so that you have less sunlight exposure during the winter. That's, I think, a pretty minor criticism; you know, holding out for an effect. I think if there were any effect they still would've seen something with this size study. If people want to repeat it in higher latitudes, then that would be reasonable, it would seem. Vitamin D's been very interesting in the last ten years; we've discovered a lot more about it, above and beyond the classical view of it. Taking vitamin D supplements does seem to help reduce the incidence and severity of autoimmune diseases like Multiple Sclerosis. We've been paying a lot closer – I know we've talked about it before on the show[link needed]; we've been paying a lot closer attention to vitamin D, adjusting the levels that we think are the minimum normal levels and increasing the recommendation for supplementation. I definitely find that – that physicians, primary care doctors, and others who are checking vitamin D levels a lot more often now, it's almost become routine, and then recommending supplements for those whose levels are very low. So that's been a pretty significant change just over the last four or five years, which is interesting, but doesn't prevent the common colds. If you're concerned about it, what I would recommend is just having your levels checked and if it's low, supplement it; if it's not low, don't worry about it. That seems to be the bottom-line recommendation at this point.
Harpooning Satellites (19:42)
Bee Brains (30:50)
S: Alright Rebecca, tell us about scientists studying bee brains.
R: Yes, scientists are studying bee brains, turns out. Bee brain - very good insult you'd think, but no, bee brains are apparently very interesting to scientists who want to make robots that can process sensory information. What these scientists who are at the Universities of Sheffield and Sussex, what they're doing in, they're researching how bee brains process sight and sound and they're hoping to apply that to robotics. And right now, a lot of the research into artificial intelligence is being done on human and you know primate simulations of artificial intelligence. And there's not a lot really going on in terms of insect intelligence or in this case honey bee intelligence. What they're hoping to do is make a tiny flying robot that can behave like a bee. This could for instance help pollination, they could do a sort of artificial pollination process. Or it could be bumped up into a larger scale and be used for something like search and rescue. Being able to survey a landscape, process the information, and find what you're looking for That could be very very important in a robot. So, that's what they're doing. They haven't actually made the bee brain yet, the artificial bee brain, unfortunately. It sounds like this research is still kind of early on. Oh, and one other thing that I thought was interesting is that the article mentions that many scientists have started using graphics cards as number crunching engines, because they're cheaper and easier to use than traditional super computers. So, that's what they're planning to use in this research. They're going to put models of bee sensory systems on graphics cards, and hopefully that will be powerful enough to run a bee brain.
J: That's awesome.
R: It's kinda cool. And yeah, it's a nice solution just in case our biologists are unable to save the bees from that whole horrific collapse.
E: Extinction, yeah...
S: Rebecca do you know how many neurons there are in the bee brain - the honey bee brain.
R: I'd say at least seven, eight...
S: At least - yeah.
(laughter)
S: Anyone have a serious guess?
R: I do not.
J: I don't know. 5 million.
E: Number of neurons?
B: How many neurons..?
E: How many neurons are in a human brain?
S: About a hundred billion.
E: Hundred billion. So a bee brain..? A billion?
B: I know it's as big as the little ball at the tip of a pen.
S: Mmmhmm.
B: That transports the ink. I know it's like that's how tiny .
J: A hundred million I say.
B: Five hundred thousand?
E: Probably about a billion.
R: I'd say a billion.
S: Wow you guys are all over the place. 960,000.
R: Wow
S: Less than a million.
E: Barely a million.
S: Cockroach has about a million. Mouse - 75 million. Human, about a hundred billion.
R: Oh yeah mice are the other that's one of the other common research...
J: So I won!
B: No. What'd you say Steve.. Jay?
J: I said uhh uhh uhh 900 million.
R: You can't even remember what the actual figure was so you can cheat. That is pathetic.
(laughter)
S: 960,000. That's a lot. That's still a lot to model, and you know they have some complicated algorithms in there, sure. That's 10 to the 9th synapses, so that's a lot.
R: I mean they don't have to perfectly recreate it though. THey just have to find the important parts of it.
S: Yeah.
R: The artificial jellyfish that sceintists were making. Science has a benefit over evolution in that they don't have to try and fail and try and fail and have a bunch of parts that don't really do exactly what they want to do. They can pick and choose. So, with that in mind, you know, they don't necessarily have to recreate each and every neuron, they just need to find what's responsible for evaluating the sensors input that the bees get and processing that in some way. Which is still, you know, an enormous problem.
S: It's probably a huge chunk of the bee brain.
R: Yeah. Yeah, definitely.
S: By the way, how many neurons are there in a sponge?
R: Ooh.
B: I'm gonna guess none.
S: Yeah, zero, correct.
R: Really?
S: Yeah.
R: Aww. Poor sponge.
J: So what do they do?
S: What about a round worm?
B: Don't you watch Sponge Bob Rebecca? Isn't it obvious?
S: Sponge Bob does have a brain.
R: Uhhh. I don't because I'm an adult.
B: That's right he does. They showed it.
R: But also Steve, do you just, do you have all these at your fingertips all the time? Is this just common neurologist factoids?
J: This is what they do when they're at the hospital Rebecca they hit each other up. <nerd voice>Oh how many brain cells are in a Troglomage.</nerd voice>
S: A Trolodyte? Yeah.
(laughter)
J: Some dude's like sipping coffe, and he's like <nerd voice>oh I believe it's blah blah blah</nerd voice>. You know it's like.
S: C. Elegans the round worm is an animal used in a lot of neurological studies, because it has only 302 neurons. We've mapped the entire C. Elegans or round worm brain.
B: They're awesome, they are so helpful.
S: Yeah.
Who's That Noisy? (36:17)
Questions and Emails
WTC-7 on 9/11 (38:18)
Science or Fiction (50:44)
Item #1: Recent research supports the claim that the rise in allergies in recent decades is due excessive cleanliness and hygiene. Item #2: Theoretical physicists claim that quantum mechanics supports the notion that an event can be both a cause and an effect of another event. Item #3: Recent study shows that commonly prescribed Beta Blockers do not protect against heart attack and stroke.
Skeptical Quote of the Week (1:06:34)
For my part, whatever anguish of spirit it may cost, I am willing to know the whole truth; to know the worst and provide for it.
Patrick Henry
Announcements (1:07:46)
References
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