Recent comments in /f/askscience
[deleted] t1_jcm1fdu wrote
[deleted] t1_jcm0u6d wrote
Reply to comment by ronmfnjeremy in Does regularly taking aspirin reduce its effectiveness to reduce pain? by tiltedpyramid
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[deleted] t1_jcm0jxm wrote
Reply to comment by ronmfnjeremy in Does regularly taking aspirin reduce its effectiveness to reduce pain? by tiltedpyramid
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madnux8 t1_jcm0241 wrote
Reply to Why that walking with the arms moving is easier than walking with them still? by BossBo161812
Walking is actually a form of controlled falling. As you are mid stride, you are in a kind of state of free fall and the motion of your legs trys to twist your body. Your arms swing counter to your legs to counter balance that twist.
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[deleted] t1_jcluc5d wrote
Reply to comment by -Metacelsus- in Are there any known endogenous retroviruses that can cause active infections, and is this possible in principle? by amlyo
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[deleted] t1_jclu8nk wrote
-Metacelsus- t1_jclu1iy wrote
Reply to comment by za4h in Are there any known endogenous retroviruses that can cause active infections, and is this possible in principle? by amlyo
If it's endogenous then the creature is already infected.
za4h t1_jclts4d wrote
Reply to comment by -Metacelsus- in Are there any known endogenous retroviruses that can cause active infections, and is this possible in principle? by amlyo
It sounds like the nature of the question is can a virus endogenous to the host creature infect that creature?
[deleted] t1_jcltp4j wrote
Reply to comment by Alittlebitmorbid in Can taking the pill delay menopause? by SouthFar412
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[deleted] t1_jcltc76 wrote
PerpetuallyLurking t1_jclt72k wrote
Reply to If UV radiation is used to disinfect and sterilise things then why isn't everything the sun touches (your skin, the sidewalk etc) sterile? by Critwhoris
Well, we keep touching them. That doesn’t help. Neither would nighttime. Even if the radiation was consistently strong enough to sterilize the sidewalk, as soon as someone walks on it at nighttime, you’ve got bacteria waiting for morning. Never mind all the northern sides of buildings that don’t see direct sunlight.
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echawkes t1_jcls73x wrote
Reply to If UV radiation is used to disinfect and sterilise things then why isn't everything the sun touches (your skin, the sidewalk etc) sterile? by Critwhoris
The frequency of radiation used to sterilize things (like operating rooms in a hospital) is in the UVC range. UVC light is completely blocked by the earth's atmosphere: the UV light you are exposed to on the earth's surface is UVA and UVB.
TomCollator t1_jclrt75 wrote
Reply to comment by TheCrafter1205 in How would a scientist be able to tell the difference between a blood sample from two totally different animals? by EastClintwood89
This link suggests a different story.
https://crimereads.com/forensics-on-trial-americas-first-blood-test-expert/
However, young pigs can have a few nucleated blood cells up to age 8 months. As pig are frequently slaughtered around 4-7 months, they can have some nucleated red blood cells.
[deleted] t1_jclr7yb wrote
WazWaz t1_jclqyke wrote
Reply to How would a scientist be able to tell the difference between a blood sample from two totally different animals? by EastClintwood89
Easy, inject a little of each into an iguana. The sick/dead iguana got the human blood. Also works in reverse.
Indeed, this is how blood identification works: you inject a little human blood into a chicken, then harvest the antibodies it produces in response. These antibodies can then be used to check if a blood sample is human (eg. only the human blood would react, the antibodies would have no effect on iguana blood).
Reisevi3ber t1_jclq4q5 wrote
Reply to comment by supapoopascoopa in Are there any known endogenous retroviruses that can cause active infections, and is this possible in principle? by amlyo
Which ones can cause autoimmune diseases and cancers?
ProfessionalDaikon16 t1_jclpxfi wrote
Reply to If UV radiation is used to disinfect and sterilise things then why isn't everything the sun touches (your skin, the sidewalk etc) sterile? by Critwhoris
When we use UV radiation it isn’t blocked by anything and hits the bacteria directly. After about 15-20 minutes the DNA is too damaged to allow the bacteria to replicate and thrive. The UV radiation we receive is mostly blocked by the ozone layer so most of the energy isn’t enough to do enough damage. If it could do the type of damage you’re inquiring about, life wouldn’t be able to survive at all.
mook1178 t1_jclo52f wrote
Reply to comment by KnoWanUKnow2 in If UV radiation is used to disinfect and sterilise things then why isn't everything the sun touches (your skin, the sidewalk etc) sterile? by Critwhoris
>But enough sunlight will kill most microorganisms.
I have read studies that homes with open window curtains during the day actually have less bacteria and mold. UV sterilization was their reason why.
BloodshotPizzaBox t1_jclnk7v wrote
Reply to comment by papad622 in If UV radiation is used to disinfect and sterilise things then why isn't everything the sun touches (your skin, the sidewalk etc) sterile? by Critwhoris
Well, over 3 million people die each year from waterborne pathogens. I can assure you that germs are the much bigger problem to have here.
hraath t1_jcm1pvl wrote
Reply to comment by TheSimpleHumans in What decides which wavelength to reflect and which one to be absorbed in an object? by TheSimpleHumans
The keyword for this is "chromaphore", if you want to dig deeper. This will take you to molecular orbital theory, that is the description of the energetic states of electrons in molecules.