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Why is it that the vertical trend of stable oxidation states varies so much horizontally across the periodic table? Why is that carbon(IV) is more stable than lead(IV), but osmium(VI) is more stable than iron(VI)? Is there an underlying trend, or is it completely unpredictable? Plasmic Physics ( talk) 00:50, 21 May 2012 (UTC)
Let me explain why I think magnesium could be a factor in obesity. First, the obvious explanation, i.e. too much calorie intake is, I think, not so plausible, because obese people actually don't eat that much calorie-wise, at least not the obese people who I know. Also, most people will be at some constant weight, so they are in dynamical equilibrium between calorie intake and calorie use. Then that dynamical equilibrium could in theory be reached at any weight, there is no good reason why at an intake of say, 3000 Kcal/day you have to weigh 100 kg, and not 70 kg or 150 kg. Most of the calories are burned by muscles, the fat tissue doesn't use a lot of energy, so you could just as well be at the same equilibrium of 3000 Kcal energy intake and energy use, but at a much lower body weight.
In fact, I weigh only 60 kg, yet I eat on average 3600 Kcal per day. Some of my obese family members eat way less than I do, but they are also eating a lot less healthy foods. Now, some time ago I posted here about magnesium, when I checked my diet I found that my magnesium intake was way too high (I get about 1 gram of magnesium per day from eating whole grain bread, potatoes, brown rice, whole grain pasta, and bananas). However, since then I've read that my magnesium intake may be normal, and that most people are actually magnesium deficient. Now, magnesium plays an important role in metabolism, so I thought that perhaps one can explain why some people are obese as follows.
If I eat X calories a day then I could gain or lose weight until I reach dynamical equilibrium where I burn X calories per day. If my food does not contain enough magnesium, then the metabolism becomes less efficient, it would take a cell longer to burn energy, so for my body to burn X calories per day would take a larger store of energy in my body, therefore I would be a lot fatter. Count Iblis ( talk) 03:10, 21 May 2012 (UTC)
Is there a concept in cartography that is analogous to resolution? By this I mean, will a particular map have a property that, say, features smaller that 10m2 are ignored? I just want to know what this is called so that I can read about it. ike9898 ( talk) 14:04, 21 May 2012 (UTC)
I want to make a working 1/12 scale model of this: http://upload.wikimedia.org/wikipedia/commons/f/f3/TrevithicksEngine.jpg or something much like it, any ideas where I can find plans of how it's made?
Kitutal ( talk) 16:12, 21 May 2012 (UTC)
Yea, or just hide a little battery powered motor inside Kitutal ( talk) 15:57, 22 May 2012 (UTC)
I was watching this video, http://www.youtube.com/watch?v=RDDfkKEa2ls&feature=related
And some of the lightning looks quite purple. What causes that? Is it just the camera, or does it really look purple? ScienceApe ( talk) 16:27, 21 May 2012 (UTC)
Is there somewhere in North America that would have a very similar climate to that of Sydney, Australia for example? Or Perth, Australia?
More generally, are there tables that answer such questions?
Eg, is the climate of Portugal very similar to that of Northern California (both being on the west coast of a continent and at the same latitude)? Thanks, CBHA ( talk) 19:43, 21 May 2012 (UTC)
I've sometimes heard people claim that the diverse sexual tastes of humans is a feature that distinguishes us from all the lower animals. However, I'm heavily skeptical of any claim that separates humans from the natural world and declares "we are unique amongst all species". So, do other animals have unusual sexual interests? Are there chimps, for example, who enjoy sadism, necrophilia, pedophilia, or foot fetishes (assuming these aren't typical amongst the species)? -- 140.180.5.169 ( talk) 19:57, 21 May 2012 (UTC)
Veering way off-topic into non-scientific discussion and personal attacks. — The Hand That Feeds You: Bite 12:47, 23 May 2012 (UTC) |
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The following discussion has been closed. Please do not modify it. |
I mean just the obvious with 'intended by nature'. For example, one could ask the question "Why do some snakes have venomous teeth?". I would answer: "In order to kill their prey". If I take your approach I would have to say: "There is no answer, nature has no purpose, it just is". - Lindert ( talk) 13:41, 22 May 2012 (UTC)
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Wow, could you guys pontificate about your woodshop notions of anthroprocentrism a little bit more? We're all animals. There are plenty of animals with non-procreative sexual drives, but they seem to be the minority. However higher level social creatures have reasons for a lot of the things they do, and no, it's not something made up by the ministry of culture. But somehow I suspect the OP just wants to hear people talk about the subject. That tends to be what we do here at the reference desk, but it'd be nice if we didn't. Any specific question? Shadowjams ( talk) 04:45, 22 May 2012 (UTC)
In this paper (on royal jelly), specifically in the section " Royalactin changes Drosophila phenotypes via Egfr," there is some form of gene notation using greater than (>) symbols that I am not familiar with and cannot find a non-dense reference on google, or indeed really any useful information at all. I think it may be describing something to do with gene silencing but I'm not sure. Could anyone shed some light on this for me? Examples are:
Specifically, I'm wondering what the > and d stand for, and what relationship the > symbol denotes for the genes either side of it. Hoping someone who knows about genetics will recognise it. Thanks!! - Zynwyx ( talk) 20:37, 21 May 2012 (UTC)
Science desk | ||
---|---|---|
< May 20 | << Apr | May | Jun >> | May 22 > |
Welcome to the Wikipedia Science Reference Desk Archives |
---|
The page you are currently viewing is an archive page. While you can leave answers for any questions shown below, please ask new questions on one of the current reference desk pages. |
Why is it that the vertical trend of stable oxidation states varies so much horizontally across the periodic table? Why is that carbon(IV) is more stable than lead(IV), but osmium(VI) is more stable than iron(VI)? Is there an underlying trend, or is it completely unpredictable? Plasmic Physics ( talk) 00:50, 21 May 2012 (UTC)
Let me explain why I think magnesium could be a factor in obesity. First, the obvious explanation, i.e. too much calorie intake is, I think, not so plausible, because obese people actually don't eat that much calorie-wise, at least not the obese people who I know. Also, most people will be at some constant weight, so they are in dynamical equilibrium between calorie intake and calorie use. Then that dynamical equilibrium could in theory be reached at any weight, there is no good reason why at an intake of say, 3000 Kcal/day you have to weigh 100 kg, and not 70 kg or 150 kg. Most of the calories are burned by muscles, the fat tissue doesn't use a lot of energy, so you could just as well be at the same equilibrium of 3000 Kcal energy intake and energy use, but at a much lower body weight.
In fact, I weigh only 60 kg, yet I eat on average 3600 Kcal per day. Some of my obese family members eat way less than I do, but they are also eating a lot less healthy foods. Now, some time ago I posted here about magnesium, when I checked my diet I found that my magnesium intake was way too high (I get about 1 gram of magnesium per day from eating whole grain bread, potatoes, brown rice, whole grain pasta, and bananas). However, since then I've read that my magnesium intake may be normal, and that most people are actually magnesium deficient. Now, magnesium plays an important role in metabolism, so I thought that perhaps one can explain why some people are obese as follows.
If I eat X calories a day then I could gain or lose weight until I reach dynamical equilibrium where I burn X calories per day. If my food does not contain enough magnesium, then the metabolism becomes less efficient, it would take a cell longer to burn energy, so for my body to burn X calories per day would take a larger store of energy in my body, therefore I would be a lot fatter. Count Iblis ( talk) 03:10, 21 May 2012 (UTC)
Is there a concept in cartography that is analogous to resolution? By this I mean, will a particular map have a property that, say, features smaller that 10m2 are ignored? I just want to know what this is called so that I can read about it. ike9898 ( talk) 14:04, 21 May 2012 (UTC)
I want to make a working 1/12 scale model of this: http://upload.wikimedia.org/wikipedia/commons/f/f3/TrevithicksEngine.jpg or something much like it, any ideas where I can find plans of how it's made?
Kitutal ( talk) 16:12, 21 May 2012 (UTC)
Yea, or just hide a little battery powered motor inside Kitutal ( talk) 15:57, 22 May 2012 (UTC)
I was watching this video, http://www.youtube.com/watch?v=RDDfkKEa2ls&feature=related
And some of the lightning looks quite purple. What causes that? Is it just the camera, or does it really look purple? ScienceApe ( talk) 16:27, 21 May 2012 (UTC)
Is there somewhere in North America that would have a very similar climate to that of Sydney, Australia for example? Or Perth, Australia?
More generally, are there tables that answer such questions?
Eg, is the climate of Portugal very similar to that of Northern California (both being on the west coast of a continent and at the same latitude)? Thanks, CBHA ( talk) 19:43, 21 May 2012 (UTC)
I've sometimes heard people claim that the diverse sexual tastes of humans is a feature that distinguishes us from all the lower animals. However, I'm heavily skeptical of any claim that separates humans from the natural world and declares "we are unique amongst all species". So, do other animals have unusual sexual interests? Are there chimps, for example, who enjoy sadism, necrophilia, pedophilia, or foot fetishes (assuming these aren't typical amongst the species)? -- 140.180.5.169 ( talk) 19:57, 21 May 2012 (UTC)
Veering way off-topic into non-scientific discussion and personal attacks. — The Hand That Feeds You: Bite 12:47, 23 May 2012 (UTC) |
---|
The following discussion has been closed. Please do not modify it. |
I mean just the obvious with 'intended by nature'. For example, one could ask the question "Why do some snakes have venomous teeth?". I would answer: "In order to kill their prey". If I take your approach I would have to say: "There is no answer, nature has no purpose, it just is". - Lindert ( talk) 13:41, 22 May 2012 (UTC)
|
Wow, could you guys pontificate about your woodshop notions of anthroprocentrism a little bit more? We're all animals. There are plenty of animals with non-procreative sexual drives, but they seem to be the minority. However higher level social creatures have reasons for a lot of the things they do, and no, it's not something made up by the ministry of culture. But somehow I suspect the OP just wants to hear people talk about the subject. That tends to be what we do here at the reference desk, but it'd be nice if we didn't. Any specific question? Shadowjams ( talk) 04:45, 22 May 2012 (UTC)
In this paper (on royal jelly), specifically in the section " Royalactin changes Drosophila phenotypes via Egfr," there is some form of gene notation using greater than (>) symbols that I am not familiar with and cannot find a non-dense reference on google, or indeed really any useful information at all. I think it may be describing something to do with gene silencing but I'm not sure. Could anyone shed some light on this for me? Examples are:
Specifically, I'm wondering what the > and d stand for, and what relationship the > symbol denotes for the genes either side of it. Hoping someone who knows about genetics will recognise it. Thanks!! - Zynwyx ( talk) 20:37, 21 May 2012 (UTC)