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According to a news article discussing the recent massive blackouts in India, [1], 1/3 of India's 1,200,000,000 never have access to a supply of grid electricity at all, under the best of circumstances, even for part of each day. It's hard to imagine viewing a house for sale in the US or the UK and hearing that there is no electric line close enough to supply it with electricity. How long ago were electric lines extended to more than 2/3 of the population of the US, the UK, France, and Germany ? Was it 100 years ago, 50 years ago, or what? Do the nonelectric 400 million Indians use Kerosene lamps, candles, or what, once the sun goes down? Edison ( talk) 01:13, 2 August 2012 (UTC)
A 113-year old person has about a 50% chance of surviving to age 114 on his/her 113th birthday, but a 114-year old person has about a 30% chance of surviving to age 115 on his/her 114th birthday. How come? Futurist110 ( talk) 02:46, 2 August 2012 (UTC)
I want to point out that the annual mortality rate stays roughly constant at ages 110-113, yet rapidly increases for ages 114 and 115. Look at the Gerontology Research Group's supercentenarian tables and you'll see what I mean. Futurist110 ( talk) 02:49, 2 August 2012 (UTC)
Human mortality after age 110 is at at a constant level of λ = 0.7. This implies an annual probability of death of qx = 0.5. This result confirms the previous analysis by Robine et al. (2005). Correspondingly, life expectancy after age 110 is about 1.4 years. Beyond the age of 114, data become too sparse to allow us to make reliable statements. (emphasis added)
What is the simple way to check whether the earth wire of a house electrical circuit is properly grounded? Thank you. 175.157.5.252 ( talk) 03:17, 2 August 2012 (UTC)
Supplementary question from editor Edison moved to a new question Explain electricity consumer earthing by Keit. I moved it because an answer requires coverage of several related topics and would most likely not help the OP for this question. The OP is of course free to read the new question and its' answer(s). Keit 60.230.207.82 ( talk) 04:01, 5 August 2012 (UTC)
Was the initial condition of the Universe an infinitely tiny bit of totally empty space? Since the initial mass of the Universe would be zero, dividing zero mass by zero volume does not give a singularity.
Then cosmic inflation hits and this empty space is blown up at vast speeds. This is all fine and dandy until a virtual meson pops up. This virtual meson is then torn apart before it can pop out. In order to avoid two bare quarks, each of the quarks gets paired up with another quark, giving a universe of two mesons. Each of these two mesons is then torn up, giving four mesons. Then eight, then sixteen, etc.
Exponential meson production continues until the Universe has enough mass/energy to reach a flat state and this stops inflation. The mesons then decay through the weak force, which applies its bias towards matter over antimatter. Would the result fit the observed Universe? Hcobb ( talk) 13:14, 2 August 2012 (UTC)
The inflaton field does not need to decay. Just mix with virtual particles and Quantum chromodynamics will suck the energy out of the inflation field into a uniform meson soup. It's Hawking radiation on steroids because as soon as any mesons are created they'll exponentially multiply like rabbits. No new physics is needed, just an empty tiny bit of space suffering from a Negative Space Wedgie. Hcobb ( talk) 00:37, 3 August 2012 (UTC)
Tango I never said that the universe had infinit pressure, what I said was that it may have had extremely great pressure. And you are correct We don't know what was there at T=0, I know that and I was not presenting unchalengeable facts, only presenting the sciontific concensous on the matter. Aliafroz1901 ( talk) 10:46, 3 August 2012 (UTC)
"and, of course, in some models, there never was a time t = 0" some models doesn't mene all thereies, and If the above linked big bang article is correct the big bang only tooke a few seconds to complete so most thereies would include a time T=0. — Preceding unsigned comment added by Aliafroz1901 ( talk • contribs) 16:32, 3 August 2012 (UTC)
How do antibodies kill antigens and pathogens? Does the antibody kill the pathogen/antigen directly, or does immune cells kill the marked pathogen/antigen, or both, and if the antibodies kill the pathogen/antigen directly, how does that work? — Preceding unsigned comment added by 187.126.186.208 ( talk) 14:10, 2 August 2012 (UTC)
I found the following in the above article
"An antibody (Ab), also known as an immunoglobulin (Ig), is a large Y-shaped protein produced by B-cells that is used by the immune system to identify and neutralize foreign objects such as bacteria and viruses. The antibody recognizes a unique part of the foreign target, called an antigen. [1] [2] Each tip of the "Y" of an antibody contains a paratope (a structure analogous to a lock) that is specific for one particular epitope (similarly analogous to a key) on an antigen, allowing these two structures to bind together with precision. Using this binding mechanism, an antibody can tag a microbe or an infected cell for attack by other parts of the immune system, or can neutralize its target directly (for example, by blocking a part of a microbe that is essential for its invasion and survival). The production of antibodies is the main function of the humoral immune system. [3]
Antibodies are produced by a type of white blood cell called a plasma cell. Antibodies can occur in two physical forms, a soluble form that is secreted from the cell, and a membrane-bound form that is attached to the surface of a B cell and is referred to as the B cell receptor (BCR). The BCR is only found on the surface of B cells and facilitates the activation of these cells and their subsequent differentiation into either antibody factories called plasma cells, or memory B cells that will survive in the body and remember that same antigen so the B cells can respond faster upon future exposure. [4] In most cases, interaction of the B cell with a T helper cell is necessary to produce full activation of the B cell and, therefore, antibody generation following antigen binding. [5] Soluble antibodies are released into the blood and tissue fluids, as well as many secretions to continue to survey for invading microorganisms."
So the answer to your first questionn seemes to be that both antibodies and immune cells kill antigens. and for the second it semes to be that antibodies kill pathogens via several methods with one of them being blocking an issential part of a microbe. Aliafroz1901 ( talk) 16:49, 2 August 2012 (UTC)
I have always been curious and puzzled by this. Can someone please explain this to me? I have consistently noticed that digital weight machines (for weighing the human body) always seem to present the person's weight in increments of 0.2 pounds. So, the person weighing himself might get results of, say, 170.0 or 170.2 or 170.4 pounds, and so forth. But, the scale will never list weights such as 170.1 or 170.3 or 170.5 pounds. Why is this? I assume it has something to do with accuracy, precision, and rounding, etc. But, still, can't the machine (scale) "round" to the 0.1 pound increment, just as easily as its programmers selecting to round it to the 0.2 pound increment? This befuddles me. Any input? Again, I am referring to digital scales that measure the human body (e.g., a person trying to lose weight). I am not referring to the smaller types of scales that might measure fruit or food (in ounces or grams) or such. Thank you! Joseph A. Spadaro ( talk) 16:51, 2 August 2012 (UTC)
Thanks to all for the valuable insight and input. It does, indeed, make sense now that I have read the above replies. I can now understand why the manufacturers choose the scales to display weight to 0.2 rather than 0.1 pounds. Thanks again. Much appreciated! Joseph A. Spadaro ( talk) 22:57, 4 August 2012 (UTC)
I was watching a video by creationist Kent Hovind and he was bashing the Big Bang Theory, and one of his claims that the BBT is false is his assertion that the singularity was spinning before it "exploded" (I know it didn't explode, but rapidly expanded). He contends that due to the conservation of angular momentum, all of the galaxies must be spinning in the same direction, but he points out that some of them are spinning in opposite directions. Two questions, can a singularity spin, and if so, was the singularity that spawned the universe, spinning before it expanded during the Big Bang? 148.168.40.4 ( talk) 17:55, 2 August 2012 (UTC)
Are there unexplored land areas left on earth? Reticuli88 ( talk) 18:47, 2 August 2012 (UTC)
Regarding the unconscious mind:
-- Melab±1 ☎ 19:10, 2 August 2012 (UTC)
I don't know all the definitions but I in all probability have accessed the unconscious mind. At times I have walked from my room to the dineing room without realiseing what I am doing. At other acasions I have gone into the bathroom, come out and forgotten all about it then have my parents remind me that I have been to the bathroom, then remember it, then think that it was all a dreem. The latter tipicly takes place when I am half asleep. Aliafroz1901 ( talk) 11:27, 3 August 2012 (UTC)
We are rarely consciously aware of what we are going to say, until we say it. If we had to consciously deliberate every word we were going to produce before we produced it, we could only do so by thinking in words about what word we were going to use, leading to an infinite regress. Hence most of what we say spontaneously is produced by the subconscious, with us only becoming conscious of what we are saying when we vocalize it. This is why we have the phenomenon of there being something on the tip of our tongues; a thought of whose struggle to make it into consciousness we are quite aware. μηδείς ( talk) 16:55, 3 August 2012 (UTC)
Why are white and black women more likely to be obese, while obesity is much rarer among women of other races? -- 108.206.7.65 ( talk) 20:35, 2 August 2012 (UTC)
Why is it that black and white women's appearances can range anywhere from very pretty to very ugly, but women from other races are almost always attractive? -- 108.206.7.65 ( talk) 21:29, 2 August 2012 (UTC)
Can someone identify these birds? The caption is "min egen bild" with a marker identifying it as Swedish; the user has no other uploads, and the filename is not particularly helpful. Nyttend ( talk) 22:11, 2 August 2012 (UTC)
I look at the photos of my friends (now 22) when they were first years (at 18), and they look so young! I am sad that we have lost our juvenile features and we seem "less cute" than before. But puberty ends between 16-18 doesn't it? What biological processes are occurring specifically? I don't think its the same type of aging that occurs later -- for example, I think our collagen remains taut, we don't develop wrinkles (yet), but what is changing? Nothing gold can stay ( talk) 23:33, 2 August 2012 (UTC)
I haven't the slightest idea of a relevant article in general, but many things cause aging during that period: taking up alcohol and cigarettes, late nights and lack of sleep, excess sun exposure, poor eating habits, stress, and even sexual activity can affect the freshness of young skin. μηδείς ( talk) 16:43, 3 August 2012 (UTC)
Science desk | ||
---|---|---|
< August 1 | << Jul | August | Sep >> | August 3 > |
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. |
According to a news article discussing the recent massive blackouts in India, [1], 1/3 of India's 1,200,000,000 never have access to a supply of grid electricity at all, under the best of circumstances, even for part of each day. It's hard to imagine viewing a house for sale in the US or the UK and hearing that there is no electric line close enough to supply it with electricity. How long ago were electric lines extended to more than 2/3 of the population of the US, the UK, France, and Germany ? Was it 100 years ago, 50 years ago, or what? Do the nonelectric 400 million Indians use Kerosene lamps, candles, or what, once the sun goes down? Edison ( talk) 01:13, 2 August 2012 (UTC)
A 113-year old person has about a 50% chance of surviving to age 114 on his/her 113th birthday, but a 114-year old person has about a 30% chance of surviving to age 115 on his/her 114th birthday. How come? Futurist110 ( talk) 02:46, 2 August 2012 (UTC)
I want to point out that the annual mortality rate stays roughly constant at ages 110-113, yet rapidly increases for ages 114 and 115. Look at the Gerontology Research Group's supercentenarian tables and you'll see what I mean. Futurist110 ( talk) 02:49, 2 August 2012 (UTC)
Human mortality after age 110 is at at a constant level of λ = 0.7. This implies an annual probability of death of qx = 0.5. This result confirms the previous analysis by Robine et al. (2005). Correspondingly, life expectancy after age 110 is about 1.4 years. Beyond the age of 114, data become too sparse to allow us to make reliable statements. (emphasis added)
What is the simple way to check whether the earth wire of a house electrical circuit is properly grounded? Thank you. 175.157.5.252 ( talk) 03:17, 2 August 2012 (UTC)
Supplementary question from editor Edison moved to a new question Explain electricity consumer earthing by Keit. I moved it because an answer requires coverage of several related topics and would most likely not help the OP for this question. The OP is of course free to read the new question and its' answer(s). Keit 60.230.207.82 ( talk) 04:01, 5 August 2012 (UTC)
Was the initial condition of the Universe an infinitely tiny bit of totally empty space? Since the initial mass of the Universe would be zero, dividing zero mass by zero volume does not give a singularity.
Then cosmic inflation hits and this empty space is blown up at vast speeds. This is all fine and dandy until a virtual meson pops up. This virtual meson is then torn apart before it can pop out. In order to avoid two bare quarks, each of the quarks gets paired up with another quark, giving a universe of two mesons. Each of these two mesons is then torn up, giving four mesons. Then eight, then sixteen, etc.
Exponential meson production continues until the Universe has enough mass/energy to reach a flat state and this stops inflation. The mesons then decay through the weak force, which applies its bias towards matter over antimatter. Would the result fit the observed Universe? Hcobb ( talk) 13:14, 2 August 2012 (UTC)
The inflaton field does not need to decay. Just mix with virtual particles and Quantum chromodynamics will suck the energy out of the inflation field into a uniform meson soup. It's Hawking radiation on steroids because as soon as any mesons are created they'll exponentially multiply like rabbits. No new physics is needed, just an empty tiny bit of space suffering from a Negative Space Wedgie. Hcobb ( talk) 00:37, 3 August 2012 (UTC)
Tango I never said that the universe had infinit pressure, what I said was that it may have had extremely great pressure. And you are correct We don't know what was there at T=0, I know that and I was not presenting unchalengeable facts, only presenting the sciontific concensous on the matter. Aliafroz1901 ( talk) 10:46, 3 August 2012 (UTC)
"and, of course, in some models, there never was a time t = 0" some models doesn't mene all thereies, and If the above linked big bang article is correct the big bang only tooke a few seconds to complete so most thereies would include a time T=0. — Preceding unsigned comment added by Aliafroz1901 ( talk • contribs) 16:32, 3 August 2012 (UTC)
How do antibodies kill antigens and pathogens? Does the antibody kill the pathogen/antigen directly, or does immune cells kill the marked pathogen/antigen, or both, and if the antibodies kill the pathogen/antigen directly, how does that work? — Preceding unsigned comment added by 187.126.186.208 ( talk) 14:10, 2 August 2012 (UTC)
I found the following in the above article
"An antibody (Ab), also known as an immunoglobulin (Ig), is a large Y-shaped protein produced by B-cells that is used by the immune system to identify and neutralize foreign objects such as bacteria and viruses. The antibody recognizes a unique part of the foreign target, called an antigen. [1] [2] Each tip of the "Y" of an antibody contains a paratope (a structure analogous to a lock) that is specific for one particular epitope (similarly analogous to a key) on an antigen, allowing these two structures to bind together with precision. Using this binding mechanism, an antibody can tag a microbe or an infected cell for attack by other parts of the immune system, or can neutralize its target directly (for example, by blocking a part of a microbe that is essential for its invasion and survival). The production of antibodies is the main function of the humoral immune system. [3]
Antibodies are produced by a type of white blood cell called a plasma cell. Antibodies can occur in two physical forms, a soluble form that is secreted from the cell, and a membrane-bound form that is attached to the surface of a B cell and is referred to as the B cell receptor (BCR). The BCR is only found on the surface of B cells and facilitates the activation of these cells and their subsequent differentiation into either antibody factories called plasma cells, or memory B cells that will survive in the body and remember that same antigen so the B cells can respond faster upon future exposure. [4] In most cases, interaction of the B cell with a T helper cell is necessary to produce full activation of the B cell and, therefore, antibody generation following antigen binding. [5] Soluble antibodies are released into the blood and tissue fluids, as well as many secretions to continue to survey for invading microorganisms."
So the answer to your first questionn seemes to be that both antibodies and immune cells kill antigens. and for the second it semes to be that antibodies kill pathogens via several methods with one of them being blocking an issential part of a microbe. Aliafroz1901 ( talk) 16:49, 2 August 2012 (UTC)
I have always been curious and puzzled by this. Can someone please explain this to me? I have consistently noticed that digital weight machines (for weighing the human body) always seem to present the person's weight in increments of 0.2 pounds. So, the person weighing himself might get results of, say, 170.0 or 170.2 or 170.4 pounds, and so forth. But, the scale will never list weights such as 170.1 or 170.3 or 170.5 pounds. Why is this? I assume it has something to do with accuracy, precision, and rounding, etc. But, still, can't the machine (scale) "round" to the 0.1 pound increment, just as easily as its programmers selecting to round it to the 0.2 pound increment? This befuddles me. Any input? Again, I am referring to digital scales that measure the human body (e.g., a person trying to lose weight). I am not referring to the smaller types of scales that might measure fruit or food (in ounces or grams) or such. Thank you! Joseph A. Spadaro ( talk) 16:51, 2 August 2012 (UTC)
Thanks to all for the valuable insight and input. It does, indeed, make sense now that I have read the above replies. I can now understand why the manufacturers choose the scales to display weight to 0.2 rather than 0.1 pounds. Thanks again. Much appreciated! Joseph A. Spadaro ( talk) 22:57, 4 August 2012 (UTC)
I was watching a video by creationist Kent Hovind and he was bashing the Big Bang Theory, and one of his claims that the BBT is false is his assertion that the singularity was spinning before it "exploded" (I know it didn't explode, but rapidly expanded). He contends that due to the conservation of angular momentum, all of the galaxies must be spinning in the same direction, but he points out that some of them are spinning in opposite directions. Two questions, can a singularity spin, and if so, was the singularity that spawned the universe, spinning before it expanded during the Big Bang? 148.168.40.4 ( talk) 17:55, 2 August 2012 (UTC)
Are there unexplored land areas left on earth? Reticuli88 ( talk) 18:47, 2 August 2012 (UTC)
Regarding the unconscious mind:
-- Melab±1 ☎ 19:10, 2 August 2012 (UTC)
I don't know all the definitions but I in all probability have accessed the unconscious mind. At times I have walked from my room to the dineing room without realiseing what I am doing. At other acasions I have gone into the bathroom, come out and forgotten all about it then have my parents remind me that I have been to the bathroom, then remember it, then think that it was all a dreem. The latter tipicly takes place when I am half asleep. Aliafroz1901 ( talk) 11:27, 3 August 2012 (UTC)
We are rarely consciously aware of what we are going to say, until we say it. If we had to consciously deliberate every word we were going to produce before we produced it, we could only do so by thinking in words about what word we were going to use, leading to an infinite regress. Hence most of what we say spontaneously is produced by the subconscious, with us only becoming conscious of what we are saying when we vocalize it. This is why we have the phenomenon of there being something on the tip of our tongues; a thought of whose struggle to make it into consciousness we are quite aware. μηδείς ( talk) 16:55, 3 August 2012 (UTC)
Why are white and black women more likely to be obese, while obesity is much rarer among women of other races? -- 108.206.7.65 ( talk) 20:35, 2 August 2012 (UTC)
Why is it that black and white women's appearances can range anywhere from very pretty to very ugly, but women from other races are almost always attractive? -- 108.206.7.65 ( talk) 21:29, 2 August 2012 (UTC)
Can someone identify these birds? The caption is "min egen bild" with a marker identifying it as Swedish; the user has no other uploads, and the filename is not particularly helpful. Nyttend ( talk) 22:11, 2 August 2012 (UTC)
I look at the photos of my friends (now 22) when they were first years (at 18), and they look so young! I am sad that we have lost our juvenile features and we seem "less cute" than before. But puberty ends between 16-18 doesn't it? What biological processes are occurring specifically? I don't think its the same type of aging that occurs later -- for example, I think our collagen remains taut, we don't develop wrinkles (yet), but what is changing? Nothing gold can stay ( talk) 23:33, 2 August 2012 (UTC)
I haven't the slightest idea of a relevant article in general, but many things cause aging during that period: taking up alcohol and cigarettes, late nights and lack of sleep, excess sun exposure, poor eating habits, stress, and even sexual activity can affect the freshness of young skin. μηδείς ( talk) 16:43, 3 August 2012 (UTC)