Wikipedia:Reference desk/Archives/Science/2016 March 15

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March 15

Intensity of Odor of Cats Feces

I have heard that the feces of a cat has a stronger odor than that of other animals. Is this correct, and if so, I would be grateful if a user could please let me know the reason for this. Thank you.Simonschaim (talk) 10:30, 15 March 2016 (UTC)

The Ref. Desk has no reason to doubt your ears so your report of what you heard is probably correct. The reason it was said in your hearing must be because fecal odor is your special interest and is the subject of everything you have contributed this year [1][2][3][4][5]. AllBestFaith (talk) 14:28, 15 March 2016 (UTC)

Stronger crap than a rabbit, goat or cow, for being a carnivore. Those dead bodies don't disappear when they're swallowed. They just add a certain oomph. Roughly tied with other meat-eaters, by my nose. Dogs can be terrible by just leaving it in the open air, if you're wondering which will make a house smell worse. InedibleHulk (talk) 14:38, 15 March 2016 (UTC)

Thank you. Simonschaim (talk) 08:09, 18 March 2016 (UTC)

Where were temperatures 11.5 C warmer on average in February?

There is a map going around at sites like [6] showing a single color for "4 to 11.5" degrees Celsius above average for February. Where was the +11.5 C? Is there a way to see a map with contours for +6, +8, +10? Note: I think I found the raw data at GIST here, and one of the locations is in northern Russia south of the Kara Sea; maybe I should write a script to get an overall view but it would be more reassuring to see a real source. I don't see any option to adjust contours on their main map.

Bonus question: if methane clathrates or methane in permafrost were being released, would the effect be localized and viewable on such a map?

On a related note, the Severnaya mine explosion in Vorkuta, Komi Republic where 38 miners were killed by a series of methane explosions prior to February 28 is at 67N 59E, with a temperature anomaly of +10.98 degrees C. Has the remarkable weather been considered as a cause of this tragedy? Wnt (talk) 11:41, 15 March 2016 (UTC)

I can't help with the maps but there is almost certainly methane being released from terrestrial permafrost as well as the arctic seabed. Some coverage of this at Arctic_methane_emissions. My understanding is that there are local hotspots but this is generally considered as a regional flux. SemanticMantis (talk) 14:36, 15 March 2016 (UTC)

That article reminds me: the Yamal peninsula, where giant sinkholes created by escaping methane have been observed, is right in the middle of the hottest zone also... Wnt (talk) 16:40, 15 March 2016 (UTC)

This question has prompted me to read further. In case these links help anyone else: Vorkuta mine disaster, Yamal_Peninsula#Yamal_craters, and Arctic methane emissions. Carbon Caryatid (talk) 21:56, 15 March 2016 (UTC)

@SemanticMantis and Carbon Caryatid: For future reference, this amateur-hour Python script produces custom plots of the temperature from the primary data linked above (open them in a web browser): [Note that data is available from other months and years, but you have to go back and put settings into the page that draws their map to get it, because I used a tmp link] (oh, most of those libraries are unneeded; this was repurposed from part of an earlier program)

# -*- coding: utf-8 -*-
import os, re, random, hashlib, hmac, logging, json, time

file_base = os.path.dirname(__file__)

input_loc = os.path.join(file_base, 'input.txt')
output_loc = os.path.join(file_base, 'output.html')

try:
    output_file = open(output_loc,'w')
except:
    sys.exit('Failed to open output.txt in program directory')
    
try:
    input_file = open(input_loc,'r')
except:
    sys.exit('Input file input.txt not found in program directory')
    
try:
    # do stuff with output_file
    print ('reading: ', input_loc, '\n')
    snarf = input_file.read() # this should be a short file!
    print (len(snarf), ' characters read\n')
    snarftable = snarf.split('\n')
    output_file.write ('<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN"\n"http://www.w3.org/TR/html4/strict.dtd">')    
    output_file.write ('<html lang="en">\n<head>\n<meta http-equiv="content-type" content="text/html; charset=utf-8">')
    output_file.write ('<title>graph: ' + snarftable[0] + '</title>\n</head>\n<body>\n')
    output_file.write ('<div style="position:relative;"><div style="position:absolute;overflow:visible;')
    output_file.write ('top:30px;left:50px;background-color:#ffffff;border:1px solid black;height:1px;width:1px;">')
    print (len(snarftable), ' fields read\n')
    for x in snarftable:
        x = re.findall('\-?\d+\.?\d*',x) #This does not savvy ".5", etc.
        if (x):
            for i in range(len(x)):
                x[i] = float(x[i])

        if (len(x)>4):
            lon = x[2]
            lat = x[3]
            color = int(round((x[4] + 2)*256/14))
            if color < 0:
                color = 0
            if color > 255:
                color = 255
            color = str(hex(color))[2:4]
            if (len(color) == 1):
                color = "0" + color
            color = color + "0000"
            # convert to 000000 to FF0000
            xpos = round((180 + lon)*512/180) # 1024 pixels wide
            ypos = round((90 - lat)*512/180) # 512 pixels deep - simple equirectangular projection!
            output_file.write('<div style="position:absolute;left:' + str(xpos) + 'px;top:')
            output_file.write(str(ypos) + 'px;width:6px;height:6px;background-color:#' + color + ';"></div>')
        output_file.write('\n')

    output_file.write ('</body>\n</html>')
        
finally:
    output_file.close()

The result shows a focus of warm air all over Russia, radiating out from the area I mentioned above. However, the preceding months are very different, with lesser warming in the far north over the Arctic. Wnt (talk) 18:34, 24 March 2016 (UTC)

When scientists need cocaine for an experiment, where do they get the cocaine from?

When an experiment need cocaine, for example, for testing the preferences of mice given free sex, free sugar, or free cocaine, where do they get the cocaine from?--Scicurious (talk) 16:00, 15 March 2016 (UTC)

From the drug cabinet. When I was recovering from extensive mouth surgery I was prescribed cocaine mouthwash. Yes I did try swallowing it. To me the effect was like 17 double espressos, won't be doing that again. Greglocock (talk) 16:14, 15 March 2016 (UTC)

Right, lots of human medical use for cocaine addition to the types of experiment OP is talking about. Some of these are covered at Cocaine#Medical. SemanticMantis (talk) 16:27, 15 March 2016 (UTC)

I would assume it varies some according to what part of the world you're talking about. Countries where drugs are more closely tied to violence or addiction would be more likely to enforce more restrictions than those there really isn't much violence or addiction. Ian.thomson (talk) 16:23, 15 March 2016 (UTC)

From places like this [7]. Search /cocaine vendor laboratory research / for more companies that can provide cocaine for research purposes. SemanticMantis (talk) 16:26, 15 March 2016 (UTC)

Note that cocaine is "Schedule II" in the U.S., which says it has accepted medical use, as opposed to marijuana for which medical marijuana is not accepted as a use. (Politics and truth are not on speaking terms) I recall once getting a sort of air-based injection spray of the stuff as a local anaesthetic into a toe prior to injected anaesthesia before having a small part of a toenail removed. Wnt (talk) 16:44, 15 March 2016 (UTC)

Marijuana is schedule 1 because there are effective medications that provide better results. To get off schedule 1 as a medicine, it would need to prove it has the same benefit without increased risk (the same standard for all new medication). Inhaling burnt organic matter in any form is carcinogenic. It's silly to pretend the reason is medical when use is overwhelmingly recreational and comes with the same complications of tobacco. At least argue it's freedom of choice rather than healthful. Even tobacco companies didn't claim it was medicinal. --DHeyward (talk) 03:42, 16 March 2016 (UTC)

In the U.S., from a DEA-licensed supplier. To lawfully obtain controlled substances, you have to be registered with the DEA, and comply with the relevant laws and procedures, like filling out the paperwork so the DEA can track the drug to ensure you aren't selling it on the black market or whatever. --71.119.131.184 (talk) 19:15, 15 March 2016 (UTC)

Yes, this is the correct answer. And it's a huge pain in the ass. Looie496 (talk) 02:04, 16 March 2016 (UTC)

Notice too that an average mouse weighs between 10–25 g. That's 3,000x less than the average human. The cocaine required for an experiment with mice is in the order of 50mg. No matter what happens with the cocaine, that would not impact the total amount of cocaine in the black market, nor would get anyone very high. A typical dose of cocaine for recreational purposes is about 100–200 mg. --Llaanngg (talk) 21:49, 15 March 2016 (UTC)

@Llaanngg: You're trying to use logic, and logic has absolutely no place in the War on Drugs. You should read how NIDA kept any kind of marijuana out of researchers' hands (except to 'prove' it was harmful by asphyxiating monkeys with thick pot smoke or something). They were so effective at stopping research that literally into the 90s they were claiming that marijuana worked without a receptor, by black magic or something, thereby making a heroic stand in defense of Crohn's disease, obesity, etc. that has helped to preserve them right up until the present day. Wnt (talk) 00:19, 16 March 2016 (UTC)

Although I don't know anything about the difficulties to access marijuana for scientific purposes, I know that drug policy is not just a big set of meaningless rules. Access to drugs for scientific purposes is regulated by international treaties, which the US is expected to abide to. Taht is, it has to comply with the Convention’s provisions on the control of certain drugs while ensuring that these drugs are available for the scientific community. There are plenty of commercial providers of chemical substances in small doses, be it a drug like cocaine, or radioactive material, among lot of controlled stuff. I don't know of any single case of abuse, or crime committed by scientists who had access to these substances. As said, the amounts are just way too small to be useful for some high impact act. Llaanngg (talk) 01:47, 16 March 2016 (UTC)

The regulations apply to suppliers as well. They don't make batches in mouse quantities but they account for what they make. The same is true for firearms. There is a company that makes the 30mm Gatling gun for the A-10 and a company that makes 7.62mm mini-gun. Who they transfer them to is tightly regulated. Different agencies, different treaties but same types of compliance by both manufacturers and their customers. --DHeyward (talk) 03:51, 16 March 2016 (UTC)

How long it takes to charge a scooter battery from the engine

My scooter (a Yamaha Vity 125) cranks but won't start. Assuming the battery is flat, I've asked a friend to jump start it with me tomorrow morning. If that works, how long should I run the engine to get a good charge back in, and is it better to do that idling or riding around?

This happened after I left the scooter parked for nearly a month in cold weather, under a carport. The lights were off. Do batteries normally go flat in those conditions, or should I replace it? 94.194.199.193 (talk) 22:57, 15 March 2016 (UTC)

1) If it cranks, then the battery isn't completely dead.

2) Yes, all batteries lose charge over time, and a month might be enough time to lose enough charge that it can no longer start the engine.

3) If the battery went completely dead, then it might freeze and crack. Since it still cranks, the entire battery hasn't gone dead, but possibly some cells might have gone dead and cracked. If so, then it may not be able to hold enough charge to start the engine, no matter how long you charge it. StuRat (talk) 00:19, 16 March 2016 (UTC)

Riding around. Buy a battery charger and use it, and/or buy a new battery. Also buy a voltmeter, they only cost 10 bucks, tho I picked some up for about a dollar off aliexpress. Greglocock (talk) 00:45, 16 March 2016 (UTC)

A voltmeter is often useless as it is an open circuit test. Bad batteries can read full voltage with no load. --DHeyward (talk) 03:54, 16 March 2016 (UTC)

A voltmeter is an excellent way of monitoring voltages while the scooter has the ignition on or is being cranked. Just because you choose to test open circuit doesn't mean everybody else has to. For the OP, if the voltage falls to less than 8V when cranking then you have a duff battery or a realted problem.Greglocock (talk) 04:55, 16 March 2016 (UTC)

If you're in the USA, visit a car parts store like AutoZone and so long as they aren't crazy-busy, they'll put a battery tester on it for you. That'll let you know whether you just have insufficient charge, whether one or more cells has died or whether the battery charging circuit inside the scooter has failed. I don't know about scooters - but in a small car, you can generally get enough charge into the battery with just 10 minutes of driving to be able to start the engine. If you think about it, this would be essential if you used your car (or scooter) for a bunch of short trips - requiring it to be restarted many times with only short trips in between. SteveBaker (talk) 02:54, 16 March 2016 (UTC)

I don't suggest the "drive it around while it charges" method. The problem is that if it stalls, or you just forget and turn it off, before it's fully charged, then you are away from home with no working transportation. So, if you are going to do that, just circle the block, so you won't have to push it very far if it does stall. StuRat (talk) 05:26, 16 March 2016 (UTC)

The battery in the Yamaha Vity 125 is a YUASA YTX7A-BS 12V open lead acid type, capacity 6Ah (at C10 rate). This seller advises charging for at least 1h with an independant charger or driving at least 30km after installation. Alternative brands that have the same dimensions 150 x 87 x 94 mm and negative terminal on the right can be fitted. For better performance i.e. no self discharge, more cold starting power, no acid leakage and less weight, it is possible to replace it with a more expensive lithium battery Skyrich YTX7A-BS HJT 2.4Ah. AllBestFaith (talk) 13:52, 16 March 2016 (UTC)