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Is the tail of C/2014 Q2 (Lovejoy) currently pointing roughly toward the Pliedies? I could see a fuzzy spot and perhaps some tail. Bubba73 You talkin' to me? 00:49, 17 January 2015 (UTC)
Awkward phrasing, I know. But I am not sure of the term to describe this concept, so I write out the question like so. Anyway, I know that a normal human eye can certainly distinguish orange and yellow on the visible light spectrum, but how close do they have to be to be distinguishable? I mean, in my crayon box, there may be "Lemon", and there may be "Yellow", and they look very similar to each other until I use them to mark the paper and see a slight difference. 71.79.234.132 ( talk) 05:40, 17 January 2015 (UTC)
Let's say that we have a hypothetical crime scene. My understanding is that the perpetrator's DNA can be extracted if the perpetrator leaves behind any of the following at the crime scene: his blood, semen, feces, hair, or skin cells. Is my understanding correct on those five items? (I believe so, but I am not 100% sure.) Now, my real question involves two other items: perspiration and urine. Do those items also contain the perpetrator's DNA? Let's assume that the items mentioned above are of sufficient quantity for DNA testing. Thanks. Joseph A. Spadaro ( talk) 07:13, 17 January 2015 (UTC)
Thanks, all. Joseph A. Spadaro ( talk) 19:08, 20 January 2015 (UTC)
Can anyone identify this species? Someone else uploaded it, so all I know is that it's a skink in Australia: what part of the country, what exact size, etc. I can't tell. All I can suggest is (1) checking the uploader's contributions to see if there's a geographic pattern (i.e. if he has a bunch of Australian photos from a specific region), although I have to run and can't get that now by myself, and (2) perhaps this is in the country's northern regions, as EXIF says that this is taken in late September; it looks like a rather lush environment, not the kind of thing you'd expect to see at the end of winter in a temperate environment. Nyttend ( talk) 12:05, 17 January 2015 (UTC)
in a human somatic cell, in the autosome pairs, is one of a pair totally from the mother and the other totally from the father? thx. 72.183.121.78 ( talk) 12:54, 17 January 2015 (UTC)
thx. that is very interesting. I guess my question should be: is most (or almost all) of one of a pair of autosomes from the mother and most of the other from the father (especially before a lot of cell divisions)? 72.183.121.78 ( talk) 15:58, 17 January 2015 (UTC)
I really appreciate your patience. if I may: in the first few divisions after the egg is fertilized and absent the rare mitotic recombination, is one of the pair almost totally from the mother and the other almost totally from the father? 72.183.121.78 ( talk) 03:47, 18 January 2015 (UTC)
thx much. 72.183.121.78 ( talk) 12:58, 18 January 2015 (UTC)
I've always wondered, with all the hormonal treatment given to lots of people in modern society, where does the hormones in pills etc. come from? Be it testosterone, estrogen or some other hormone, and be it in the form of pills or alcoholic gels etc.
It has to be artificially generated/created before put into pills or gels, right, but from where and how? It just seem so strange to me that they can create and put something like that into pills and the likes, something which are supposed to only be naturally generated inside an individual's body.. When it comes to other types of medicine, it is easier to understand how and from where the key ingredients come, because they are often natural resources that can be gathered.
So, to repeat my question; How, from where and from what do they make hormones used in medical treatment? 2A02:FE0:C711:5C41:1CEC:1194:53D:204E ( talk) 13:36, 17 January 2015 (UTC)
"something which are supposed to only be naturally generated inside an individual's body." is an interesting comment. Chemicals don't know where they come from, they just exist, and have no really intrinsic difference based on their origin. It's something of a marvel of modern science that we can start from a non-biological chemical and make one, but total synthesis isn't a new field of productive research (and vitalism started to be disputed and disproven almost two centuries ago). DMacks ( talk) 16:37, 17 January 2015 (UTC)
Thanks for answers. Today's education for me, that is. They say we all learn something every day.. :) I agree by the way that it is "something of a marvel of modern science that we can start from a non-biological chemical and make one." 2A02:FE0:C711:5C41:1CEC:1194:53D:204E ( talk) 18:17, 17 January 2015 (UTC)
On an interesting historical note, the original source of the precursors for the hormones in birth control pills was yams. See our article. In the 1950s some yam species were found to be abundant sources of steroid compounds that could be converted to sex hormones. And another thing: in the Trobriand Islands, yams are a staple food, and the yams found there contain steroids with contraceptive activity. The regular consumption of these was a factor in the development of sexual mores that are very alien to traditional Western society. -- 71.104.75.148 ( talk) 01:52, 20 January 2015 (UTC)
When I read the information about tanks` maximum range , I noticed an issue which is that the M1 Abrams and all other tanks that use diesel fuel have almost the same range , but once a time I hear that the M1 Abrams refuel each four and a half hours while diesel fuel tanks refuel every 24 hours while watching a documentary film , so how can I understand this contradiction ? 46.185.161.90 ( talk) 14:02, 17 January 2015 (UTC)
Actually, as our article states, the U.S. military typically fuels the M1 with JP-8 jet fuel. The U.S. military uses JP-8 for all its ground vehicles as well as aircraft, to simplify logistics. Other users of the M1, like the Australian military, do use diesel. Also interesting is that the M1 is different from most tanks in having a turbine engine, instead of a reciprocating engine like what you would find in a car or truck. -- 71.104.75.148 ( talk) 02:03, 20 January 2015 (UTC)
Do mallard ducks in Britain migrate for the winter, and if so, where?
Also, presuming they do migrate, is there documented behaviour of them returning to the same lakes, year after year? If yes, are these lakes the lakes by which they hatched?-- Leon ( talk) 16:01, 17 January 2015 (UTC)
The RSPB is your friend.-- Phil Holmes ( talk) 18:21, 17 January 2015 (UTC)
Are all roads stabilised either mechanically, or with a binder? Is it possible to have an unstabilised road other than a dirt road or roads with unbound bases. Can the term stabilisation also be used for the surface course which is normally bound with bitumen? 82.132.239.245 ( talk) 18:56, 17 January 2015 (UTC)
So, I heard that basically the most damaging things to skin are the sun, and heat. Those who avoid the two (use sun-screen and don't take scalding showers) have fresh skin for longer. I've used this advice to good effect and can easily subtract a quarter of my age and be believed (say 24 at 32).
separately, I've always towel/air dried my hair. I've recently adopted a new look, and was taught to blow-dry for it. (Though not strictly necessary; but if I don't, if I air-dry, then it is wavy/curly instead of straight. I prefer the latter.)
So, here is my question: just how damaging is blow-drying (scalding hot) hair in the mornings, to skin, over a period of years (if I had this look for years)?
Best would be if I could simply see some comparison pictures. For example, here is a picture of someone half of whose face happened to be sunlit over a period of years: http://www.doobybrain.com/2012/06/04/unilateral-dermatoheliosis-the-effect-of-the-sun-on-human-skin/ (and there are many similar ones). It's a dramatic demonstration.
Are there some photos I could see of scalps and faces of blow-drier users versus air-drier users? I'd just like to know how strong the effect is. The blow-drier is scalding hot, but lasts just a couple of minutes. (I don't think drying on the cold setting produces the desired effect with the technique I've learned, and anyway I would catch a cold every morning I wash my hair. Towel/air drying produces totally different hair.)
Also, if you can't find any references, photos, I've thought of another way. If there are actors/actresses who obviously and for years wear a straightened, blow-dried look (that they obvoiusly repeat frequently) I could look at their faces versus ones with shorter/wavier hair or who have gone on record as air-drying. It is easy to follow actors' aging over a period of years (longitudinally) since they're always in the public eye. 212.96.61.236 ( talk) 22:17, 17 January 2015 (UTC)
Science desk | ||
---|---|---|
< January 16 | << Dec | January | Feb >> | January 18 > |
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. |
Is the tail of C/2014 Q2 (Lovejoy) currently pointing roughly toward the Pliedies? I could see a fuzzy spot and perhaps some tail. Bubba73 You talkin' to me? 00:49, 17 January 2015 (UTC)
Awkward phrasing, I know. But I am not sure of the term to describe this concept, so I write out the question like so. Anyway, I know that a normal human eye can certainly distinguish orange and yellow on the visible light spectrum, but how close do they have to be to be distinguishable? I mean, in my crayon box, there may be "Lemon", and there may be "Yellow", and they look very similar to each other until I use them to mark the paper and see a slight difference. 71.79.234.132 ( talk) 05:40, 17 January 2015 (UTC)
Let's say that we have a hypothetical crime scene. My understanding is that the perpetrator's DNA can be extracted if the perpetrator leaves behind any of the following at the crime scene: his blood, semen, feces, hair, or skin cells. Is my understanding correct on those five items? (I believe so, but I am not 100% sure.) Now, my real question involves two other items: perspiration and urine. Do those items also contain the perpetrator's DNA? Let's assume that the items mentioned above are of sufficient quantity for DNA testing. Thanks. Joseph A. Spadaro ( talk) 07:13, 17 January 2015 (UTC)
Thanks, all. Joseph A. Spadaro ( talk) 19:08, 20 January 2015 (UTC)
Can anyone identify this species? Someone else uploaded it, so all I know is that it's a skink in Australia: what part of the country, what exact size, etc. I can't tell. All I can suggest is (1) checking the uploader's contributions to see if there's a geographic pattern (i.e. if he has a bunch of Australian photos from a specific region), although I have to run and can't get that now by myself, and (2) perhaps this is in the country's northern regions, as EXIF says that this is taken in late September; it looks like a rather lush environment, not the kind of thing you'd expect to see at the end of winter in a temperate environment. Nyttend ( talk) 12:05, 17 January 2015 (UTC)
in a human somatic cell, in the autosome pairs, is one of a pair totally from the mother and the other totally from the father? thx. 72.183.121.78 ( talk) 12:54, 17 January 2015 (UTC)
thx. that is very interesting. I guess my question should be: is most (or almost all) of one of a pair of autosomes from the mother and most of the other from the father (especially before a lot of cell divisions)? 72.183.121.78 ( talk) 15:58, 17 January 2015 (UTC)
I really appreciate your patience. if I may: in the first few divisions after the egg is fertilized and absent the rare mitotic recombination, is one of the pair almost totally from the mother and the other almost totally from the father? 72.183.121.78 ( talk) 03:47, 18 January 2015 (UTC)
thx much. 72.183.121.78 ( talk) 12:58, 18 January 2015 (UTC)
I've always wondered, with all the hormonal treatment given to lots of people in modern society, where does the hormones in pills etc. come from? Be it testosterone, estrogen or some other hormone, and be it in the form of pills or alcoholic gels etc.
It has to be artificially generated/created before put into pills or gels, right, but from where and how? It just seem so strange to me that they can create and put something like that into pills and the likes, something which are supposed to only be naturally generated inside an individual's body.. When it comes to other types of medicine, it is easier to understand how and from where the key ingredients come, because they are often natural resources that can be gathered.
So, to repeat my question; How, from where and from what do they make hormones used in medical treatment? 2A02:FE0:C711:5C41:1CEC:1194:53D:204E ( talk) 13:36, 17 January 2015 (UTC)
"something which are supposed to only be naturally generated inside an individual's body." is an interesting comment. Chemicals don't know where they come from, they just exist, and have no really intrinsic difference based on their origin. It's something of a marvel of modern science that we can start from a non-biological chemical and make one, but total synthesis isn't a new field of productive research (and vitalism started to be disputed and disproven almost two centuries ago). DMacks ( talk) 16:37, 17 January 2015 (UTC)
Thanks for answers. Today's education for me, that is. They say we all learn something every day.. :) I agree by the way that it is "something of a marvel of modern science that we can start from a non-biological chemical and make one." 2A02:FE0:C711:5C41:1CEC:1194:53D:204E ( talk) 18:17, 17 January 2015 (UTC)
On an interesting historical note, the original source of the precursors for the hormones in birth control pills was yams. See our article. In the 1950s some yam species were found to be abundant sources of steroid compounds that could be converted to sex hormones. And another thing: in the Trobriand Islands, yams are a staple food, and the yams found there contain steroids with contraceptive activity. The regular consumption of these was a factor in the development of sexual mores that are very alien to traditional Western society. -- 71.104.75.148 ( talk) 01:52, 20 January 2015 (UTC)
When I read the information about tanks` maximum range , I noticed an issue which is that the M1 Abrams and all other tanks that use diesel fuel have almost the same range , but once a time I hear that the M1 Abrams refuel each four and a half hours while diesel fuel tanks refuel every 24 hours while watching a documentary film , so how can I understand this contradiction ? 46.185.161.90 ( talk) 14:02, 17 January 2015 (UTC)
Actually, as our article states, the U.S. military typically fuels the M1 with JP-8 jet fuel. The U.S. military uses JP-8 for all its ground vehicles as well as aircraft, to simplify logistics. Other users of the M1, like the Australian military, do use diesel. Also interesting is that the M1 is different from most tanks in having a turbine engine, instead of a reciprocating engine like what you would find in a car or truck. -- 71.104.75.148 ( talk) 02:03, 20 January 2015 (UTC)
Do mallard ducks in Britain migrate for the winter, and if so, where?
Also, presuming they do migrate, is there documented behaviour of them returning to the same lakes, year after year? If yes, are these lakes the lakes by which they hatched?-- Leon ( talk) 16:01, 17 January 2015 (UTC)
The RSPB is your friend.-- Phil Holmes ( talk) 18:21, 17 January 2015 (UTC)
Are all roads stabilised either mechanically, or with a binder? Is it possible to have an unstabilised road other than a dirt road or roads with unbound bases. Can the term stabilisation also be used for the surface course which is normally bound with bitumen? 82.132.239.245 ( talk) 18:56, 17 January 2015 (UTC)
So, I heard that basically the most damaging things to skin are the sun, and heat. Those who avoid the two (use sun-screen and don't take scalding showers) have fresh skin for longer. I've used this advice to good effect and can easily subtract a quarter of my age and be believed (say 24 at 32).
separately, I've always towel/air dried my hair. I've recently adopted a new look, and was taught to blow-dry for it. (Though not strictly necessary; but if I don't, if I air-dry, then it is wavy/curly instead of straight. I prefer the latter.)
So, here is my question: just how damaging is blow-drying (scalding hot) hair in the mornings, to skin, over a period of years (if I had this look for years)?
Best would be if I could simply see some comparison pictures. For example, here is a picture of someone half of whose face happened to be sunlit over a period of years: http://www.doobybrain.com/2012/06/04/unilateral-dermatoheliosis-the-effect-of-the-sun-on-human-skin/ (and there are many similar ones). It's a dramatic demonstration.
Are there some photos I could see of scalps and faces of blow-drier users versus air-drier users? I'd just like to know how strong the effect is. The blow-drier is scalding hot, but lasts just a couple of minutes. (I don't think drying on the cold setting produces the desired effect with the technique I've learned, and anyway I would catch a cold every morning I wash my hair. Towel/air drying produces totally different hair.)
Also, if you can't find any references, photos, I've thought of another way. If there are actors/actresses who obviously and for years wear a straightened, blow-dried look (that they obvoiusly repeat frequently) I could look at their faces versus ones with shorter/wavier hair or who have gone on record as air-drying. It is easy to follow actors' aging over a period of years (longitudinally) since they're always in the public eye. 212.96.61.236 ( talk) 22:17, 17 January 2015 (UTC)