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Physiology & Medicine / Re: Is seeing rays possible?

« on: 29/09/2020 06:31:34 »

We see electromagnetic radiation only in a very small part of the spectrum - the visible range; the skin can perceive infrared radiation as heat - but nothing more. Some animals are a little more fortunate: birds, for example, see a new, unimaginable color in ultraviolet light. Therefore, the most ordinary-looking birds for us can look very bright for their relatives. Snakes are better at sensing infrared radiation than we are; however, they do not see it with their eyes, but sense it with special receptors between the eyes and nose. No living creature on the planet looks into other EMR areas.

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Cells, Microbes & Viruses / Re: What's the best way to wash fresh fruit and veg?

« on: 28/09/2020 06:02:55 »

If you are sure of the purity of vegetables and fruits, then you can do with running water. For purchase rules are different. First of all, we get rid of wax and paraffin. To do this, wash fruits and vegetables in water using a separate brush, and then rinse them under the tap.

If vegetables and fruits are bought for children, then we first soak the future salad or dessert in cold water (at the same time we will get rid of the share of harmful substances inside the fruit, if any), and then we wash it in the usual way and cut off the skin. Of course, for homemade apples this "trick" will be unnecessary, but for glossy apples it is highly recommended.

If you have washed fruits and vegetables, then eat them immediately or put them in jams, salads, etc. Do not store them for a long time after washing. Firstly, they quickly deteriorate, and secondly, they lose vitamins and other useful substances.

Use only stainless steel appliances for cleaning.

If you have yellow spots on your vegetables (zucchini, cucumbers, or potatoes), get rid of them immediately and without thinking. Such spots are a sign of excess nitrates. You can reduce nitrate levels by soaking potatoes or carrots in salted water for a day. But along with nitrates, you will also get rid of vitamins.

Fruits and vegetables prepared for feeding babies are recommended to be washed not with running water, but with distilled water.

Never use dishwashing detergent or regular fruit and vegetable soap. Chemical components can get under the skin of the fruit and cause poisoning.

Means for washing vegetables and fruits - shop and home
Whoever advises you to use laundry soap - or any dishwashing detergent - to process fruits and vegetables, reaffirming the efficacy of the classic "well, you see, nothing happened to me" - don't listen! A categorical prohibition of these products when washing fruits! They are not washed to the end (even if this is a children's "ECO-remedy"), and the components of the product, along with fruits and vegetables, are sent directly to the body.

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Plant Sciences, Zoology & Evolution / Re: What are your favourite Plant Pictures?

« on: 27/09/2020 16:13:29 »

I love mountains and these simple flowers. In general, I love when beauty is simple and natural.

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Physics, Astronomy & Cosmology / Re: Can you see anything if you travel faster than the speed of light?

« on: 25/09/2020 07:24:01 »

Take the sun and the earth (distance 8 light minutes). Let's say the time is 1:30 on earth, we see the sun at 1:22, moving at the speed of light, we just hit the sun at 1:30 (8min.), Moving 8 times faster (for indicative and), we overcome this distance is only 1 minute and we get into the sun at 1:23, and since the distance between us and the earth is 8 holy minutes, we (if we could) see the earth at 1:15. If we go back to earth at the same speed, we will get home at 1:16, that is, in our past.
But such a movement is not possible, because the speed of light is the maximum possible speed.

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Physiology & Medicine / Re: Is our blood type related to the antibodies we produce?

« on: 24/09/2020 09:01:41 »

A specific set of proteins (antigens) is expressed on the membranes of erythrocytes - non-nuclear red blood cells that are responsible for transporting oxygen. These proteins are capable of triggering immune responses aimed at recognizing foreign proteins and eliminating them (elimination). Each antigen has its own antibody in the blood plasma. Therefore, the blood group is determined by the presence of one or another antigen protein on the surface of erythrocytes and an antibody protein in the plasma. Some antigens are expressed to a lesser extent and cause immune responses much less frequently, therefore they are not of high clinical significance, and some to a greater extent, and neglect of them can lead to death for the recipient.

In the AB0 system, antigens A and B can be contained on the surface of erythrocytes, and antibodies anti-A and anti-B in the blood plasma. In cases where antigen A and antibody anti-A intersect, destruction of red blood cells occurs. So if a person has antigen A, then they have anti-B antibody. There are four possible combinations (groups):

0 (I) - there are no antigens A and B on erythrocytes, but the corresponding antibodies are in the plasma;

A (II) - antigen A on erythrocytes, anti-B antibody in plasma;

B (III) - antigen B on erythrocytes, anti-A antibody in plasma;

AB (IV) - antigens A and B on erythrocytes, no antibodies in plasma.

Different subgroups can exist within the same blood group. Antigens A and B are encoded by several different genes, and depending on which gene encodes a particular antigen, their immunogenicity will differ. For example, the A1 antigen is slightly less immunogenic than the A2 antigen.

All this is important both in blood transfusion and in organ transplantation, because antigens A and B can be expressed not only on the surface of erythrocytes, but also in many other places: on the membrane of liver cells, on the surface of the endothelium - the cell layer lining the vessels from the inside ... And if the blood groups of the organ donor and the recipient do not match, then, most likely, such a transplant will not be able to take place.

The Rh factor system consists of blood groups determined by 59 antigens. The most important are antigens D, C, c, E, e, which have immunogenic properties. The commonly used terms "Rh positive" (Rh +) and "Rh negative" (Rh-) refer only to the presence or absence of the most immunogenic Rho (D) antigen.

The Kell system includes 25 antigens, including antigen K - the most immunogenic after A, B and D. As in the case of the Rh factor, people are divided into two groups (Kell-negative and Kell-positive) based on the presence of the K antigen in erythrocytes or lack thereof. This antigen is not counted in plasma transfusion, but is counted in red blood cell transfusion.

Blood groups are determined by a set of genes that do not affect either the character or the color of the hair and eyes, or the rate of absorption of food, or the predisposition to certain diseases. Not a single study in the world, conducted on large reliable statistical samples, found links between blood groups and other functions or characteristics of the body. There is no scientific background or evidence that blood type diets and other similar methods work.

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Physics, Astronomy & Cosmology / Re: What happens inside a black hole, and how do black holes evaporate?

« on: 23/09/2020 08:12:00 »

If we consider a black hole as a relativistic object, then there should be no evaporation, but alas, the theory of relativity does not provide answers to absolutely all questions in modern physics.

Evaporation of black holes is predicted by quantum theory. In a vacuum, particle-antiparticle pairs are constantly being born. If there is no black hole, then the annihilation of particles occurs, and the energy returns to the vacuum and everything becomes as it was. This process is called vacuum polarization or boiling.

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General Science / Re: Do Varicose Veins Really Benefit From Compression Socks/Stockings ?

« on: 22/09/2020 11:49:01 »

Compression garments have been shown to prevent the onset of symptoms of varicose veins after exercise or at the end of the day. Scientists from Macy University in Auckland found that 93% of patients with varicose veins experience leg pain without compression socks, and only 14% of subjects wearing compression socks also experienced similar pain after exercising or taking a long walk.