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16

Short answer, your eyelids does not block all light. Since they are only a thin layer of skin, the light is able to pass through although not completely obviously. Since the eyes are still completely functional when you close them, only covered by the eyelids, you are able to see when light strikes your face.


16

Sometimes men wake up with an erection in the morning. Why does this happen? Shortly speaking: REM (Rapid Eye Movement) is one phase of sleep. During this phase we dream and some of our neurotransmitter are shut off. This include norepinephrine, which is involved in controlling erection. Norepinephrine prevents blood to enter the penis (preventing the ...


10

I will just show the statistics of last attempt to mimic the brain process. Last year Japan launched there fastest supercomputer: K computer OR SPARC64 VIIIfx 2.0GHz Features: Manufacturer: Fujitsu Cores: 705,024 Linpack Performance (Rmax) 10,510 TFlop/s Theoretical Peak (Rpeak) 11,280.4 TFlop/s Power: 12,659.89 kW Memory: 1,410,048 GB ...


9

There are 2 reasons for light to appear red through the eyelids. 1) Eyelids get a rich supply of blood which contains iron (in hemoglobin). The iron in blood absorbs all colors of light but reflects red light (reference). 2) Our tissue transmits red wavelengths of light very well, but it doesn't transmit blue or wavelengths of light towards the blue end of ...


9

Yes, it can, but it is extremely rare. ... nosebleeds are rarely fatal, accounting for only 4 of the 2.4 million deaths in the U.S. in 1999 [1]. The main issue is that epistaxis can be a sign of potentially fatal diseases: The instances in which nosebleed is potentially fatal are those in which there is a history of recent head injury, severe ...


9

During the time when you are not drinking water you still loose some water to sweating and urine. Sweating is (especially in hot climates) an important function of the body to maintain the body temperature in desired range. If this water is not replaced, the body gets dehydrated. This induces a reaction which reduces the activity of the "body thermostat" to ...


6

Interestingly this effect seems to be true - there is one paper which claims that fasting for three days leads to the depletion of unused (and especially damaged) immune cells to save energy. When food is back at normal rates, the body starts to renew these cells which have been depleted before. This process also seems to enhance the self-renewal process of ...


5

Any injury, that results in external bleeding can lead to death, since it is a breach in the body's defenses and an entry point for pathogens. Explanation: When you have nose bleeding the blood must be coming from somewhere. Usually from inside your body. That means there is a hole in your body which is big enough for blood to stream out. That in return ...


5

As @WYSIWYG pointed, muscular atrophy is the main cause for height decrease. A spine injury leads to neural impairment and paresis / paralysis. This affects directly muscular trophism. It also limits physical activity, this being another favoring factor for muscular atrophy and overweight issues [1]. Association of bone degenerative processes (osteoporosis, ...


4

Alright, so this answer is partially based off the ideas presented by Bobson above. What i did was take his Excel spreadsheet idea and put that into the upper section. Then, I used the amounts used on the website he linked to check the proper amounts needed in the body. I then used those numbers to reverse engineer how much of each compound would be needed ...


3

Yes. Usually only in the case of someone with hemophilia (no blood clotting) but it could theoretically occur with any serious uncontrolled nosebleed. Since blood in the stomach tends to cause vomiting, you could also lead to a scenario where someone who was uncomfortable with blood would pass out due to being scared of the blood and then aspirate (puke and ...


3

What you are looking for is a spirometer. There are different types of spirometers serving different purposes like the Incentive spirometer and the peak flow meter. I would suggest that you go through the wikipedia page on it to get more info.


3

The liver does quite a lot of "housekeeping". It is responsible for a lot of energy metabolism: Gluconeogenesis (the synthesis of glucose), Glycogenolysis (the breakdown of glycogen into glucose), Glycogenesis (the synthesis of glycogen from glucose). It is important for protein degradation as well as for amino acid synthesis, as well as in the lipid ...


3

People with Shorter height may outlive Taller ones. It is a statistically established fact that they are more successful in terms of money, as the study published Journal of Applied Psychology, (Vol 89(3), Jun 2004, 428-441). But, still in the health, the counterpart succeed over the former. The Effect of Physical Height on Workplace Success and ...


3

I think that the advantages of using both hands with equal ease is quite evident whether it be sports, at your work or while you are doing your household chores. An obvious advantage is using both hands to write or draw with both at the same time. I would be focusing on the disadvantages that may be faced. 1) Ambidextrous people are more prone to ...


3

Vitamin A: One study conducted in the 60's claims that vitamin A acid prevents formation of comedones in Acne Vulgaris [1]. Another one conducted in the 70's found no significant improvement of plantar warts when vitamin A acid was applied topically [2]. Vitamin D: Agents like calcipotriene associated with topical steroids are effective against psoriazis ...


3

Human Microbiome Project According to Published data on HMP website: The human microbiome consists of all the microorganisms that reside in or on the human body. They may cause illness but some are necessary for good health. There total count is 10 times more than Human cells. ~800 genomes had been sequenced. ~5000 Human sample had been used. Include 14 ...


2

In general, if you want to know "exactly how much of X on an average is needed to be consumed to cause death", then the magic search term for Google is "LD50", that is the dose that kills 50% of victims. I've seen the LD50 for distilled water quoted as 90ml/kg for rats (that is, 90 ml per kg of body mass). I presume that figure comes not from theorising ...


2

Thanks for the searching and quoting Ilmari. According to some theories, and perhaps there is some research on stool to support these, we can aid our intestines for producing beneficial bacteria by eating PREbiotic foods which supposedly help create a good environment in the intestines for producing healthy bacteria on its own. Some foods that are supposed ...


2

There are two levels to take your question at. The first is simpler but I'm not sure if it is what you are looking for: If you imagine the heart and all the blood vessels in your body as a closed plumbing system with no leaks (not entirely accurate) then when the heart contracts and squeezes the blood from the ventricles the total surface area the blood is ...


2

Sun and moon-faking devices exist. Not sure about 'biosphere'. I have personally observed one for honeybees, but that one was fairly crude(bees are dumb). It was just a big room with a hive stand in the middle and a series of fluorescent lights on the ceiling that turned on one after the other. The goal was to mess with bee circadian rhythms and see which ...


2

I am afraid you cannot build the classic ECG using only 1 hand. Probably, you can measure HR - heart rate accordingly to pressure detection and similar sensors and from that you can simulate ECG by picture. Simulate I mean you cannot build any reliably ECG curve on the monitor, but can show some waves after every heart beat.


2

Females are defined as the sex that produces that bigger gamete (ovule) while the males are those from the gender that produce the smaller gametes (spermatozoid). Because producing big gametes is costly, the number of females fix the reproductive limit in the population and in other words the variance in reproductive success in males is higher than in ...


2

Yes it can but it is very rare. Most often when you get a nosebleed it is either a vein or capillary that ruptures. However in some cases it is arterial bleeding which is always an emergency. I have honestly noticed when I have nosebleeds often each one is worse than the previous with some having a lot of bleeding but still no gushing from an artery. ...


2

The Human Microbiome Project collected samples as shown in the image below from healthy volunteers: They give an estimate of about 8 Million genes in the human microbiome, which is about 360x the number of genes in the human genome. See here for their press release with a lot of information. Additionally these two articles are as well interesting, if you ...


1

Light can affect retina in many ways [1]: photothermal mechanisms - exposure to intense flashes of less than 20 microseconds that cause a rise in temperature of at least 10 degrees Celsius [5]; photomechanical mechanisms - exposure to flashes shorter than 5 nanoseconds [5]; photochemical mechanisms - light is absorbed by a chromophore and leads to the ...


1

While it's always possible that a mutated eggplant will produce a new toxin, this is very unlikely. I don't know how much higher the mutation rate is near Fukushima than in general but the difference can't be huge. Even if it's, say, 5 or 10 times higher than normal (I'm making up these numbers), the risk is still tiny. Actually, plant breeders sometimes use ...


1

Another possibility is K4 device and K4 device. Beyond spirometry it can measure other variables such as: Pulmonary Gas Exchange (VO2, VCO2) Breath by Breath Technology Telemetry Data Transmission up to 1000m Indirect Calorimetry Integrated GPS System Integrated Oxygen Saturation (SpO2) Integrated 12-lead Stress Testing ECG


1

In cerebral oedema the observations (blood pressure, pulse, respiratory rate etc.) can be all over the place. They can depend on the cause e.g. infectious more likely to have raised pulse (tachycardia) with lower blood pressure (shock) but with the anxiety there might be raised blood pressure. Then with the vomiting, a symptom of cerebral oedema, this could ...


1

Caffeine is the stimulant in tea. It has different effects on different people, but if you can sleep right after drinking it, it probably isn't strong enough to have long term 'refreshing effects', And yes, the duration of your sleep does matter. If you sleep for 12 hours, much more caffeine will filter out of your blood stream than after a 1 hour nap. ...



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