Wikipedia:Reference desk/Archives/Science/2014 December 25

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December 25

Is steroid considered as protein?

194.114.146.227 (talk) 01:06, 25 December 2014 (UTC)

Steroids are all of a certain different class of molecule, and the article steroid makes this clear. If you have questions after reading the article let us know. μηδείς (talk) 01:57, 25 December 2014 (UTC)

No, steroids are not proteins. One big difference is their size, with proteins often hundreds of times the size of steroids. Insulin, which you have expressed interest in, is a medium-smallish protein, composed of only 51 amino acids (many proteins are composed of hundreds or even thousands of amino acids in each molecule), with a molecular mass of 5808 Da. (A Dalton is just a fancy name for an atomic mass unit -- roughly the mass of a hydrogen atom, the lightest atom. The molecular mass of proteins are often given in kDa, or thousands of Daltons, with the largest, the titins, up to 34,000 amino acids long and having a molecular mass of nearly 3,800 kDa = 3,800,000 Da.) Compare that with Estradiol, the steroidal estrogen hormone in many oral contraceptive pills, which has a molecular mass of only 272 Da.

Large size alone does not make a molecule fragile, with most plastics being long chain polymers with high molecular mass. Proteins, however, are composed of amino acids which are easily joined and easily separated. The introduction to our Protein article says, "Once formed, proteins only exist for a certain period of time and are then degraded and recycled by the cell's machinery through the process of protein turnover. A protein's lifespan is measured in terms of its half-life and covers a wide range. They can exist for minutes or years with an average lifespan of 1–2 days in mammalian cells." Protein#Nutrition describes how: "In animals, amino acids are obtained through the consumption of foods containing protein. Ingested proteins are then broken down into amino acids through digestion, which typically involves denaturation of the protein through exposure to acid and hydrolysis by enzymes called proteases." -- ToE 13:20, 25 December 2014 (UTC)

• Proteins are polypeptides containing the peptide bond by which the "amino" of one amino acid is linked to the carboxylic acid of the next. This is a very standardized process usually done by a gigantic specialized cellular machine called a ribosome, though non-ribosomal peptide synthesis is also possible. If you look up the structure of any compound and you do not see -NH-C(=O)- (or cyclic -N-C(=O)- in the case of proline, or, well, some enol form, or something else I forgot...) then it isn't a peptide of any sort. If you don't see several units where two carbons, one attached to an oxygen, are followed by a nitrogen, then it isn't a protein. It is possible in a very broad sense for a protein to be a steroid, though I can only think of synthetic examples,^[1] but the circumstances under which this linkage would occur are so unusual as to be essentially irrelevant. Wnt (talk) 17:34, 26 December 2014 (UTC)

Exercise routine breaks

Why is an occasional week or so long break from routine exercise or the gym considered beneficial? — Preceding unsigned comment added by 82.132.219.96 (talk) 12:46, 25 December 2014 (UTC)

The way exercise works is by causing small tears in muscles and cracks in bones, which are then repaired to make them even stronger, but these repairs take time. StuRat (talk) 15:16, 25 December 2014 (UTC)

But that's what rest days are for. I meant why so many trainers advise to take occasional longer breaks too. — Preceding unsigned comment added by 94.14.146.161 (talk) 15:53, 25 December 2014 (UTC)

I would guess that the muscle tears are mended more quickly than the bone cracks. StuRat (talk) 17:55, 25 December 2014 (UTC)

From personal experience - I've been doing 16 exercises on one shoulder for 6 weeks. This is alternate stretching and strengthening days, 5 days a week, and 2 days off. I stopped for Christmas last friday, ie have now had a week off, and the whole shoulder feels a lot less noticeable than it was last week. So yes, everything gets a chance to calm down, fix itself. Greglocock (talk) 01:11, 26 December 2014 (UTC)

Hi there. I hope that someone can find you a reference (this being the Reference Desk) from a trustworthy source that answers your question. While the above answers are, I am sure, offered in good faith, they're just guesses from people who probably have no particular qualifications or specific knowledge to answer your question. Remember that questions at the Reference Desk are answered by volunteers and are essentially entirely unfiltered. TenOfAllTrades(talk) 15:40, 26 December 2014 (UTC)

There are references out there that attest to the fact that the muscles are damaged by exercise and need to repair and that not allowing this can cause overtraining syndrome. Unfortunately I cannot link my chosen refernce because the site is blacklisted for some reason and Wiki wont allow it. I cant be botthered linking to another site unless that one is blacked too. Anyway this desk is filtered by all sorts of people who will revert, delete, or close discussions if they dont like them. Arent there TOAT?--86.168.107.141 (talk) 20:33, 27 December 2014 (UTC)

Research

How is it decided whether a university or a company r&d department does a certain research? — Preceding unsigned comment added by 94.14.146.161 (talk) 15:15, 25 December 2014 (UTC)

At a company it should be based on potential return on investment, although occasionally there's a public relations angle to it, too, like when a car company makes an electric car they know will lose money. The idea here is that, in the long run, the good PR will pay off more than the losses on that model.

At a university, ROI is also important, but PR is a bigger consideration, as having a prestigious research program will attract better faculty, students, and grants. Government and corporate grants also tend to play a major role in the decision process. StuRat (talk) 15:20, 25 December 2014 (UTC)

That may be the case when deciding to start a major program that involves building dedicated facilities or hiring faculty with an interest in a specific area. More typically, though, tenured university Professors are free to choose their own research topics. Most University research happens because there is a professor who is interested in the topic, and he or she is able to get government or other funding to cover the cost of the research. ROI and PR for the university play little role in these decisions.--Srleffler (talk) 19:25, 27 December 2014 (UTC)

Christmas Day moon eclipse

Was there a Christmas Day solar eclipse in 810?--Doug Coldwell (talk) 15:41, 25 December 2014 (UTC)

Oh yes. I remember that eclipse it well. Yet it was Selene that darkened! Only the night before I was discussing the possibility of an eclipse with King Arthur and his good Lady beautiful Guinevere. Alas, the velum scroll upon which I recorded my observations of the followings nights spectacle has long since crumbed into dust and some wizard has messed with the calendar to such an extent that I don't know what day it supposed to be any more. But I beg of you, not to feel disheartened at this sorry tale. For good tidings I bring. Another wizard has since conjured up a wondrous and magical contrivance, of a like, that my frail mind struggles to comprehend. Yet you Sir, in your enlightened age, may profit from a 'seeing' of what secrets it lays open for all to see: Partial eclipse on 14.12.810 at 21:52 Merry December the 14th. Kind Regards Merlin.--Aspro (talk) 16:37, 25 December 2014 (UTC)

Bear in mind that there was a calendar screwup that had to be corrected in 1582, resulting in 10 days being dropped from the calendar. That puts the Dec 14th eclipse on Dec 24th in today's calendar...and if you were in the right place on the earth at the time - maybe it was December 25th in that local time zone. (Although time zones weren't precisely agreed upon...so even that is a tough concept). At any rate, it wasn't the same day that it is today...so what exactly that does to the significance of the "Dec 14th" eclipse is a matter of your point of view. Is Xmas day defined by a point in the earth's orbit, an exact number of 365.2425 day intervals since some event (not quite the same thing), or just when people happened to hold their celebrations as directed by local custom? That long ago, the pagan celebration of the winter solstice was probably still the dominant holiday - and when they celebrated that could well have been independent of the somewhat flaky calendar they had back then (eg by watching where the sun was along the horizon when it rose). We know (from simple orbital math) the exact moment when the eclipse happened - what we don't know is what day that was considered to be back then - and what it should properly be named today. That's what makes this tricky to answer...not when the eclipse actually happened. Also, solar eclipses aren't visible from the entire planet - so it's not enough to ask whether one happened on that day without also specifying where the observer was when he was looking for it. SteveBaker (talk) 17:36, 25 December 2014 (UTC)

The date adjustment was not a fixed 10 days, but varied by century due to the calendar drift over time. As noted here, a date in the 800s would need a 4 day adjustment moving from Gregorian to Julian calendars, rather than a 10 day adjustment. Also, it would seem likely that Aspro's link is using modern Gregorian dates rather than Julian, which would imply you are making the correction in the wrong direction. Gregorian December 14, 810 would have been Julian December 10, 810 at the time. Dragons flight (talk) 17:59, 25 December 2014 (UTC)

Ah. A jester or naïve with a trefoil cap has blessed us with his foolery upon these joyous times. Welcome fool. Thy juster, beseech thee... oh tell thee fool– for I long to know. Just is why, the 10 days of 1500 - 1700 leaves out of the summing of 700-900? Oh, I have long been amused by good foolery. So summons up your very best! If the answer give us good cheer, then feel blessed to take your foolery to to Wikipedia_talk:Reference_desk/Science#Depression_and_Tiredness. And a very merry Christmas. --Aspro (talk) 23:02, 25 December 2014 (UTC)

That was certainly one of the more flowery personal attacks I've seen here. ←Baseball Bugs ^{What's up, Doc?} carrots→ 17:35, 26 December 2014 (UTC)

Perhaps we should play a Christmas carol and meditate on the notion that the occurrence of an eclipse on any given Christmas depends on when people think Christmas is, by which calendar, by which sect and belief, and therefore, by extension, if you decide in your heart that it is Christmas, the very next eclipse you see is a Christmas eclipse as much as one has ever been. Wnt (talk) 18:06, 26 December 2014 (UTC)

Is it still the case that Eastern Orthodox's December 25th falls on or about January 6th in the western calendar? ←Baseball Bugs ^{What's up, Doc?} carrots→ 18:16, 26 December 2014 (UTC)

I found the idea here. --Doug Coldwell (talk) 17:44, 25 December 2014 (UTC)

depression and tiredness

We cannot give medical advice. If you have concerns, see a doctor. ←Baseball Bugs What's up, Doc? carrots→ 23:33, 25 December 2014 (UTC)
The following discussion has been closed. Please do not modify it.
Some people that suffers from clinical depression experience feelings of tiredness and feel the need to sleep much more than usual. a. How and why is feeling of tiredness and lethargy connected to depression? b. Is it better to fight off the feeling of tiredness and sleepiness or to go along with it (eg. to sleep much more than usual) ? — Preceding unsigned comment added by 161.139.102.6 (talk) 16:19, 25 December 2014 (UTC) “How and why is feeling of tiredness and lethargy connected to depression?” It used to be thought that clinical depression was purely psychological, i.e., all in the mind. It now appears evident that it is neurological and any change that came about at the same time (as say a brake up of a romantic relationship) is just a temporal coincidence. Which introduces the earlier observation: “need to sleep much more than usual”. What is normal? We are animals that did all our evolution without being regulated by clocks. Teenagers go through a faze were their genetic programming requires them to stay up late and lay in bed the next day. The are not lazy – its built in. As they go through such ordeals as 'growing pains' their brains are also developing. As every individual is different, some may require more time for their biofeedback system to establish a state of homoeostasis (or balance). This may require periods of more sleep than some others can get by on. There is a saying that: The road to hell is paved with good intentions. Fighting the natural affects (which are labeled today as 'clinical depression') by denying sleep and forcing activity can exasperate the suffering. Yet at the same time, opportunities to participate in everyday social intercourse is important so that the individuals does not lose contact with the world about them. The instincts of friends and relatives are often better in helping that those who are labeled as sufferers than those who have read something, somewhere, by an expert, who's only qualification is that he has passed exams and has wrote a book on what those exams indoctrinated him in.--Aspro (talk) 17:31, 25 December 2014 (UTC) Serotonin plays a role in both depression and sleep regulation. There's an interesting writeup here. It's a student project and thus not a "reliable source" by Wikipedia standards but it's well written and is a fair summary. Key quote: "By disrupting the circadian rhythm of sleep-wake cycles, an imbalance in serotonin leads to restless sleep during which the subject wakes often, leading them to lack sleep at night and desire sleep during the day." Short Brigade Harvester Boris (talk) 17:39, 25 December 2014 (UTC) Looking at it from the other direction, we have Sleep deprivation#Treatment for depression. -- ToE 18:03, 25 December 2014 (UTC) Excessive sleep could also be viewed as "self-medication" for depression, along with drugs and alcohol. That is, the pain goes away for a while when asleep. StuRat (talk) 18:07, 25 December 2014 (UTC) The "which is better" cannot be answered by anyone here. You need to see a doctor. ←Baseball Bugs What's up, Doc? carrots→ 18:24, 25 December 2014 (UTC) Your question suggests that you are trying to decide how to combat depression-related oversleeping and fatigue in yourself (or perhaps someone near you). If that is the case, then you should talk to a doctor or clinical psychologist. Depression can be a serious illness that has profound impacts on an individual's quality of life. Effective treatments, such as counseling and/or medication, have been shown to help many people recover from depression more quickly than the typical person recovers without assistance. It is not necessary to suffer alone, people with depression can get help. In addition, a doctor may need to conduct a sleep study or other tests to rule out other causes of chronic oversleeping and fatigue, such as sleep apnea. Dragons flight (talk) 18:31, 25 December 2014 (UTC) {{--Aspro (talk) 20:48, 25 December 2014 (UTC)|Aspro}} Some people that suffers from clinical depression experience feelings of tiredness and feel the need to sleep much more than usual. a. How and why is feeling of tiredness and lethargy connected to depression? b. Is it better to fight off the feeling of tiredness and sleepiness or to go along with it (eg. to sleep much more than usual) ? — Preceding unsigned comment added by 161.139.102.6 (talk) 16:19, 25 December 2014 (UTC) “How and why is feeling of tiredness and lethargy connected to depression?” It used to be thought that clinical depression was purely psychological, i.e., all in the mind. It now appears evident that it is neurological and any change that came about at the same time (as say a brake up of a romantic relationship) is just a temporal coincidence. Which introduces the earlier observation: “need to sleep much more than usual”. What is normal? We are animals that did all our evolution without being regulated by clocks. Teenagers go through a faze were their genetic programming requires them to stay up late and lay in bed the next day. The are not lazy – its built in. As they go through such ordeals as 'growing pains' their brains are also developing. As every individual is different, some may require more time for their biofeedback system to establish a state of homoeostasis (or balance). This may require periods of more sleep than some others can get by on. There is a saying that: The road to hell is paved with good intentions. Fighting the natural affects (which are labelled today as 'clinical depression') by denying sleep and forcing activity can exasperate the suffering. Yet at the same time, opportunities to participate in everyday social intercourse is important so that the individuals does not lose contact with the world about them. If in doubt, see a professional psychiatrist. But don't base your decisions on something that you have read somewhere by someone that hasn't seen or doesn’t know the individual.--Aspro (talk) 16:19, 26 December 2014 (UTC) This seems like deja vu. Your question about what is "better" cannot validly be answered by anyone here. If you've got concerns about it, see your doctor. ←Baseball Bugs What's up, Doc? carrots→ 17:33, 26 December 2014 (UTC)

It is difficult to define sleepiness associated with depression scientifically. [2] Long and short sleep duration both seem to have some predictive power in indicating elevated odds that depression continues. [3] However, according to that source it "remains to be determined" whether treating them would have positive effects. In the limited case of administration of paroxetine, patients who respond to that drug with "hypersomnia" were found in a small study to be more likely to respond to it in resolution of depressive symptoms [4]; however, I wouldn't trust this to mean much even in the case where this drug is used.* The bottom line is that the data collected so far looks surprisingly scanty, considering! Wnt (talk) 00:54, 27 December 2014 (UTC)

* Per complaint, I should clarify that I mean the last study I cite is so small that I have limited confidence in its reproducibility; I am not editorializing on paroxetine per se at this time. Wnt (talk) 03:09, 27 December 2014 (UTC)

Aaron Swartz's major (possibly at MIT?)

What did/was Aaron Swartz study/studying in college? --Schweinchen (talk) 22:24, 25 December 2014 (UTC)

The article you linked says that he attended Stanford, not MIT, though if I'm interpreting the dates correctly, he quit during his freshman or sophomore year. Most people don't declare a major so early in their college education. Deor (talk) 23:44, 25 December 2014 (UTC)

Thanks. Do you happen to know what major branch of human knowledge he chose to study at Stanford? That (essential, in my opinion) bit of information seems extremely difficult to winnow in my Google searches, buried in endless lines of text mostly concerned about his death... --Schweinchen (talk) 12:49, 26 December 2014 (UTC)

Well, as I said, he was there only for a year, but in his own blog at the time he remarked that someone "asked me why I switched from computer science to sociology, I said it was because Computer Science was hard and I wasn’t really good at it, which really isn’t true at all. The real reason is because I want to save the world." And this article from the New York Daily News at the time of his death says that he "was admitted to Stanford as a sociology major, but he dropped out after a year". Deor (talk) 13:28, 26 December 2014 (UTC)

I wonder if one of the issues is that Schweinchen isn't familiar with the US undergraduate system. As I understand it, with the strong focus on Liberal arts education at many universities/colleges there the first year there tends to be very general purpose such that it often won't matter that much whether you want to do sociology, computer science, anthropology, physics, biology, psychology, law, architecture, mathematics or whatever, what you did in first year often won't restrict your major later and without needing to take extra courses. In fact this can continue to the second year, and ?beyond.

In countries inspired by the UK, such as New Zealand, Australia, Malaysia or I think India and where many bachelor degrees only last 3 years and there's a strong focus on specialised degrees, this frequently isn't the case. While you may be able to switch between a few related majors or even two fairly unrelated ones (depending on the precise requirements, university, major, courses you chose etc), having such a diverse range of options after first year without having to take at least some extra courses (in fact, since some of the lower level courses may be prerequistes or at least expected knowledge, you may need an extra semester even if you can handle the workload unless you're fairly exceptional or otherwise already know most of the stuff). While there are some moves towards more general education and a liberal arts focus, this tends still be far more limited than the US.

I think things in continential Europe tend to be more similar to the UK than the US as much as it can be said to be similar to anything when it comes to the Bachelor's or equivalen. (See Bachelor's degree as well as the earlier link on liberal arts for example.)

Nil Einne (talk) 14:22, 26 December 2014 (UTC)

Thanks, guys. --Schweinchen (talk) 21:31, 26 December 2014 (UTC)