Things you always wanted to know the answer to [Vol. 4]
Discussion
Thanks for the answers. That's really interesting. A study on rats is close enough for me, many would say!
I suppose people who live at altitude routinely experience quite low pressure, so Bolivians and Nepalese might be an interesting case study, while the inhabitants of the Dead Sea region or Holland represent the opposite.
Don't athletes sometimes train at high altitudes, or is that more to do with thin air, whatever is meant by that - possibly not the same thing as low pressure. I wonder if there are any effects on the psyche. Perhaps we all get glum when a depression passes over! It would certainly explain the nomenclature.
I suppose people who live at altitude routinely experience quite low pressure, so Bolivians and Nepalese might be an interesting case study, while the inhabitants of the Dead Sea region or Holland represent the opposite.
Don't athletes sometimes train at high altitudes, or is that more to do with thin air, whatever is meant by that - possibly not the same thing as low pressure. I wonder if there are any effects on the psyche. Perhaps we all get glum when a depression passes over! It would certainly explain the nomenclature.
allegerita said:
Trivial info: a wart is called a wrat in Dutch
Way off thread here, but this reminded me that brother in Polish is brat, very apt for Stefan, the little brother of Jadwiga, the Polish girl I was seeing in the late seventies.When her parents had gone to bed, and I was about to “get busy” on the sofa with Jadwiga, he’d creep into the room, and hide behind an armchair, watching us.
Altitude training is about conditioning the body to having less oxygen available, so when you go back to lower altitudes you're getting more oxygen than you're used to.
I live at sea level but my uncle lives about 4 meters below sea level just down the road, but I don't think that's enough of a pressure increase to make mush difference
There are some odd effects of pressure though. Oxygen is toxic above a partial pressure of about 1.6 Bar, ie breathing pure oxygen at 1.6 bar, or air at 8 Bar (oxygen being 20ish% of the air), and Nitrogen at higher pressures produces Nitrogen Narcosis, which is a bit like being drink
I live at sea level but my uncle lives about 4 meters below sea level just down the road, but I don't think that's enough of a pressure increase to make mush difference
There are some odd effects of pressure though. Oxygen is toxic above a partial pressure of about 1.6 Bar, ie breathing pure oxygen at 1.6 bar, or air at 8 Bar (oxygen being 20ish% of the air), and Nitrogen at higher pressures produces Nitrogen Narcosis, which is a bit like being drink
RizzoTheRat said:
Airliners are typically pressurised to an equivalent of 6000-8000 feet, which gets you down to about 75% of sea level pressure, so people are exposed to lower pressures pretty regularly, I'm surprised there's not been loads of studies on the effects.
Interestingly the International Space Station is pressurised to 1 Atmosphere so maybe NASA think there are some health effects at lower pressures.
Unlikely that it's the pressure per se which causes the issue, rather than the rate of change of pressureInterestingly the International Space Station is pressurised to 1 Atmosphere so maybe NASA think there are some health effects at lower pressures.
Also, older US spacecraft prior to the Shuttle used a cabin atmosphere of 5psi pure oxygen - this allowed lighter pressure vessel construction but increased danger of fire, as well as possible long term physiological issues ( though it seems to have been OK for the 14 day Apollo missions )
RizzoTheRat said:
Airliners are typically pressurised to an equivalent of 6000-8000 feet, which gets you down to about 75% of sea level pressure, so people are exposed to lower pressures pretty regularly, I'm surprised there's not been loads of studies on the effects.
Interestingly the International Space Station is pressurised to 1 Atmosphere so maybe NASA think there are some health effects at lower pressures.
People live at those attitudes on earth, so any systemic health problems will be well known and I'm pretty sure there aren't any. Interestingly the International Space Station is pressurised to 1 Atmosphere so maybe NASA think there are some health effects at lower pressures.
Bogata, Colombia is at 2,600 metres (about 8,600 ft). It is entirely possible to get off a plane there at a higher pressure there (although I'm pretty sure airliners equalise pressure slowly).
The ISS is at 1 atm for several reasons, not the least of which is fire prevention. Lower pressure/higher O2 are more susceptible to combustion, as NASA found out with the Apollo 1 fire. Also given the scientific nature of the ISS mission, it makes sense to pressurise it to 1 atm.
RizzoTheRat said:
Altitude training is about conditioning the body to having less oxygen available, so when you go back to lower altitudes you're getting more oxygen than you're used to.
I live at sea level but my uncle lives about 4 meters below sea level just down the road, but I don't think that's enough of a pressure increase to make mush difference
There are some odd effects of pressure though. Oxygen is toxic above a partial pressure of about 1.6 Bar, ie breathing pure oxygen at 1.6 bar, or air at 8 Bar (oxygen being 20ish% of the air), and Nitrogen at higher pressures produces Nitrogen Narcosis, which is a bit like being drink
Nope - altitude training is about getting the body to produce more red blood cells so that at lower altitudes (where the competition takes place) there are 'more' red blood cells available to transport oxygen. It is similar in effect (if not in law) to blood doping.I live at sea level but my uncle lives about 4 meters below sea level just down the road, but I don't think that's enough of a pressure increase to make mush difference
There are some odd effects of pressure though. Oxygen is toxic above a partial pressure of about 1.6 Bar, ie breathing pure oxygen at 1.6 bar, or air at 8 Bar (oxygen being 20ish% of the air), and Nitrogen at higher pressures produces Nitrogen Narcosis, which is a bit like being drink
Roofless Toothless said:
popeyewhite said:
Lots of old wives tales about stuff like this over the years, current (unproven) theory is the low pressure that brings bad weather compresses soft tissue which squeezes damaged/repaired nerves. I Googled that as it intrigued me, as I have lots of old joint injuries - but I enjoy cold weather quite a bit with no pain.
You know, I've always wondered about the effect of atmospheric pressure on the way we feel.I believe there is something like 10% difference in pressure between the centres of depressions and anticyclones. That seems like rather a lot to me. Does our physical or mental health alter under the influence of these extremes?
Popeyewhite is right to point out that weather changes along with pressure, but can we separate this out and just leave the purely barometric effects?
You would react to sudden changes though as the body isn't designed to deal with those quickly.
ambuletz said:
i'm trying to think of a scene in a tv show.. i wonder if anyone knows which one it is and what episode?
i'm 100% sure it's a cartoon sitcom (family guy, american dad, simpsons, futurama etc).
basically there's an art critic/teacher who looks at a painting and says 'marrrvelous', then looks at another and says the same thing. basically everything they look at (even stuff that's objectively crap) he thinks is amazing.
I think you are thinking of The Simpsons. Episode is called ‘brush with greatness’ and the character is Professor Lombardoi'm 100% sure it's a cartoon sitcom (family guy, american dad, simpsons, futurama etc).
basically there's an art critic/teacher who looks at a painting and says 'marrrvelous', then looks at another and says the same thing. basically everything they look at (even stuff that's objectively crap) he thinks is amazing.
https://youtu.be/ceQOxAfnhcY
HTH
98elise said:
I don't see why, the pressure equalises throughout your whole body so the net effect is zero. If your body was sealed then you should feel the difference, but it isn't.
You would react to sudden changes though as the body isn't designed to deal with those quickly.
I've got high blood pressure, controlled by medication down to an acceptable level. It is (hopefully) always about the same when I measure it. If barometric pressure drops by several per cent then surely there is a greater pressure difference between me and the outside world than there was before. Would that not cause some physiological or mental stresses?You would react to sudden changes though as the body isn't designed to deal with those quickly.
Roofless Toothless said:
I've got high blood pressure, controlled by medication down to an acceptable level. It is (hopefully) always about the same when I measure it. If barometric pressure drops by several per cent then surely there is a greater pressure difference between me and the outside world than there was before. Would that not cause some physiological or mental stresses?
The measurement is the difference between atmospheric pressure and blood pressure, so if it measures the same then the pressure difference between you and the outside world is the same. Your heart probably has to work less hard at lower atmospheric pressure though.HTP99 said:
V8mate said:
HTP99 said:
V8mate said:
20 years ago, and before... were dogs cold?
Are you talking about dogs in coats and jumpers?Frenchies have a very fine layer of fur, she does get cold, she shivers as does my smallest terrier; the other terrier doesn't get particularly cold though, he does have thicker fur and he's not a pussy!
All 3 have jumpers, I'm not that keen on them as I think it's more psychological on my wife's part plus they get dirty, mudyydy and when it rains, heavier and wet, if it's just me walking them I tend not to put them in their jumpers as once running around they soon warm up anyway, plus they look a bit stupid.
I think it's more of a fashion type thing than anything else TBH.
Ayahuasca said:
...so that at lower altitudes (where the competition takes place) there are 'more' red blood cells available to transport oxygen...
From the web;The choice of Mexico City to host the 1968 Olympic Games proved to be a controversial one because of the city's high altitude, 2,300m. The altitude proved an advantage in explosive events such as short-distance running, jumping, throwing and weightlifting. But the rarefied air proved disastrous for those competing in endurance events.
The high altitude led to world records in all of the men’s races that were 400m or shorter, plus the long jump and triple jump. Probably the most memorable achievement was Bob Beamon’s spectacular long jump of 8.90m - a world record that would last for 22 years.
The Don of Croy said:
Ayahuasca said:
...so that at lower altitudes (where the competition takes place) there are 'more' red blood cells available to transport oxygen...
From the web;The choice of Mexico City to host the 1968 Olympic Games proved to be a controversial one because of the city's high altitude, 2,300m. The altitude proved an advantage in explosive events such as short-distance running, jumping, throwing and weightlifting. But the rarefied air proved disastrous for those competing in endurance events.
The high altitude led to world records in all of the men’s races that were 400m or shorter, plus the long jump and triple jump. Probably the most memorable achievement was Bob Beamon’s spectacular long jump of 8.90m - a world record that would last for 22 years.
glazbagun said:
What was the first "space destroyer" type design of the Aliens /Babylon 5 theme to make it onto the screen.
I'd say that Battlestar Galactica might qualify. Also the baddie's spaceship in Battle Beyond the Stars. Oh, and the Imperial Star Destroyers in the original Star Wars, of course.
Frozen sweetcorn / pea boiling...
What's the fastest way to get peas / sweetcorn (assuming similar heat capacity and surface variation for each unit of product and an initial temperature of -20C ) up to boiling temperature?
Say the "product" goes 1/3 the way up a pan with a 20cm diameter a 15cm height.
You have a kettle which is already boiled with enough water to brim the saucepan.
Do you put a little bit in (on full stove heat), so that even if the water reduces in temperature a long way because of the effect of the frozen veg, but then there is less volume to heat.
Or do you put a lot in, so the temperature of the water does not decrease so much, but there is now a greater volume of water / product to heat?
Or is there a certain middle ground?
Wife and I disagree, I put loads in, her a little bit. We've never timed it, perhaps we should.
What's the fastest way to get peas / sweetcorn (assuming similar heat capacity and surface variation for each unit of product and an initial temperature of -20C ) up to boiling temperature?
Say the "product" goes 1/3 the way up a pan with a 20cm diameter a 15cm height.
You have a kettle which is already boiled with enough water to brim the saucepan.
Do you put a little bit in (on full stove heat), so that even if the water reduces in temperature a long way because of the effect of the frozen veg, but then there is less volume to heat.
Or do you put a lot in, so the temperature of the water does not decrease so much, but there is now a greater volume of water / product to heat?
Or is there a certain middle ground?
Wife and I disagree, I put loads in, her a little bit. We've never timed it, perhaps we should.
OyAke said:
Frozen sweetcorn / pea boiling...
What's the fastest way to get peas / sweetcorn (assuming similar heat capacity and surface variation for each unit of product and an initial temperature of -20C ) up to boiling temperature?
Say the "product" goes 1/3 the way up a pan with a 20cm diameter a 15cm height.
You have a kettle which is already boiled with enough water to brim the saucepan.
Do you put a little bit in (on full stove heat), so that even if the water reduces in temperature a long way because of the effect of the frozen veg, but then there is less volume to heat.
Or do you put a lot in, so the temperature of the water does not decrease so much, but there is now a greater volume of water / product to heat?
Or is there a certain middle ground?
Wife and I disagree, I put loads in, her a little bit. We've never timed it, perhaps we should.
I've asked this before: boil water and then put frozen peas in, or put frozen peas in cold water and bring to the boil.What's the fastest way to get peas / sweetcorn (assuming similar heat capacity and surface variation for each unit of product and an initial temperature of -20C ) up to boiling temperature?
Say the "product" goes 1/3 the way up a pan with a 20cm diameter a 15cm height.
You have a kettle which is already boiled with enough water to brim the saucepan.
Do you put a little bit in (on full stove heat), so that even if the water reduces in temperature a long way because of the effect of the frozen veg, but then there is less volume to heat.
Or do you put a lot in, so the temperature of the water does not decrease so much, but there is now a greater volume of water / product to heat?
Or is there a certain middle ground?
Wife and I disagree, I put loads in, her a little bit. We've never timed it, perhaps we should.
IIRC, the answer given was that both need the same energy (which comes from a steady gas supply)
OyAke said:
Frozen sweetcorn / pea boiling...
What's the fastest way to get peas / sweetcorn (assuming similar heat capacity and surface variation for each unit of product and an initial temperature of -20C ) up to boiling temperature?
Say the "product" goes 1/3 the way up a pan with a 20cm diameter a 15cm height.
You have a kettle which is already boiled with enough water to brim the saucepan.
Do you put a little bit in (on full stove heat), so that even if the water reduces in temperature a long way because of the effect of the frozen veg, but then there is less volume to heat.
Or do you put a lot in, so the temperature of the water does not decrease so much, but there is now a greater volume of water / product to heat?
Or is there a certain middle ground?
Wife and I disagree, I put loads in, her a little bit. We've never timed it, perhaps we should.
I just boil the kettle and pour to an inch or so above the veg. No further heat required just leave for a few minutes What's the fastest way to get peas / sweetcorn (assuming similar heat capacity and surface variation for each unit of product and an initial temperature of -20C ) up to boiling temperature?
Say the "product" goes 1/3 the way up a pan with a 20cm diameter a 15cm height.
You have a kettle which is already boiled with enough water to brim the saucepan.
Do you put a little bit in (on full stove heat), so that even if the water reduces in temperature a long way because of the effect of the frozen veg, but then there is less volume to heat.
Or do you put a lot in, so the temperature of the water does not decrease so much, but there is now a greater volume of water / product to heat?
Or is there a certain middle ground?
Wife and I disagree, I put loads in, her a little bit. We've never timed it, perhaps we should.
popeyewhite said:
Your proprioceptors would be able to detect the change in pressure. On a muggy day some people say it feels 'close'. Whether this would affect temperament is another matter.
Surely that's feeling the humidity though, not the pressure difference.Also proprioception us being able to tell where parts of your own body are in relation to each other, not meteorological sensation.
Gassing Station | The Lounge | Top of Page | What's New | My Stuff