We observe something in nature. We measure and describe that thing. We formulate theories to explain the thing and its repeatability, which may be called laws. The law describes the phenomenon because the observed behaviour of the phenomenon is what the law was invented to describe.
Having once formulated a law, we attempt to apply it everywhere. If that works, we say it applies everywhere. If it does not, we don’t.
The self fulfilling prophecy is that science describes what science was invented to describe. Science describes the universe exactly as it is. If it succeeds, the universe and scientific methodology we used are in agreement - If it fails, the methodology used is wrong and a new and better description must be found and will be found.
Do you need justification to find out scientific facts that are written into this universe using scientific methodology?!
Q: Are false pregnancy tests possible? Can a man test positive for pregnancy?
Krishna: Yes, in certain cases, a false positive is possible.
Pregnancy tests are designed to tell if your urine or blood contains a hormone called human chorionic gonadotropin (hCG). This hormone is made right after a fertilized egg attaches to the wall of a woman's uterus. This usually happens about 6 days after fertilization. If you're pregnant, levels of hCG continue to rise rapidly, doubling every 2 to 3 days.
Two main types of pregnancy tests can let you know if you're pregnant: urine tests and blood tests. Urine tests can be done at home or in a doctor's office. Many women first choose a home pregnancy test to take about a week after a missed period. Home pregnancy tests are private and convenient. These products come with instructions. After testing, you can confirm results by seeing your doctor, who can perform even more sensitive pregnancy tests.
Blood tests are done at your doctor's office, but are used less often than urine tests. These tests can detect pregnancy earlier than a home pregnancy test, or about 6 to 8 days after ovulation. But with these tests, it takes longer to get the results than with a home pregnancy test.
Two types of blood pregnancy tests are available: A qualitative hCG test simply checks to see if hCG is present. It gives a "yes" or "no" answer to the question, "Are you pregnant?"Some of these tests can detect hCG much earlier. A quantitative hCG test (beta hCG) measures the exact amount of hCG in your blood. It can find even very low levels of hCG. Because these pregnancy tests can measure the concentration of hCG, they may be helpful in tracking any problems during pregnancy. They may also (in combination with other tests) be used to rule out a tubal (ectopic) pregnancy or to monitor a woman after a miscarriage when hCG levels fall rapidly.
Some uncommon forms of testicular cancer in men also produce HCG (1). If you got a positive result on this test, you may need to get tested for cancer. You could also get a false positive if you are taking certain medications, mostly anticonvulsants and antipsychotics (2).
Errors are always possible. You have to go for second or confirmation tests if you doubt the first ones.
Q: Can anyone donate a kidney to anyone?
Krishna: Kidney donation begins with a blood test. The test will determine your blood type and if it will match the recipient's blood (compatibility). If your blood type is compatible with the recipient, two more blood tests will be done (tissue typing or genetic typing and cross-matching).
Tissue typing is a blood test that matches the number of antigens the donor and recipient share. These antigens can recognize the difference between two people's body tissue.
Each person has six basic tissue typing antigens (or markers) shared equally from their parents. The markers help tell which donor will be the best match between the recipient and donor. A parent and child would have at least 50 percent match while siblings could have a zero to 100 percent match.
The best match for the recipient is to have six out of six antigens match. (This is known as a zero mismatch.) It is possible for all six markers to match.
It is not necessary that you match your antigens for a successful transplant. Even matching one antigen may make for a more successful transplant than matching five or six antigens from a deceased donor kidney.
Cross-matching is a blood test you and the recipient will have at least two different times to see if the recipient will react to your kidney. If there is no reaction, the result is a negative cross-match. This means the transplant surgery can happen.
You can pass all of your other tests, but if you have a positive cross-match - meaning the recipient's body would attack the new kidney - you cannot donate your kidney to that person.
Also, to be considered for kidney donation, you cannot abuse drugs, including alcohol and you shouldn't have serious infections like HIV.
Q: How do scientific theories get accepted?
Krishna: By testing. Lots of times. With evidence. Lots of it, gathered repeatedly by independent researchers.
Q: Somehow I got hooked to this site. How did you achieve success in attracting people to a science site?
Krishna: Thank you! Welcome to my thrilling world!! And stay here for ever!!!
In the beginning I too faced certain problems. Then I started interactive science sessions and all the problems disappeared. People are coming in thousnads and my site is flourishing. People now trust me more than anything else They themselves are saying this.
It is how you put things before them, how you make them consider, understand, think and in the end accept things in a scientific way that makes a difference.
Q: Is anti rabies safe for a four year old?
Krishna: Yes! Infants and children can be given rabies vaccine. The dose of HDCV or PCEC for preexposure or PEP is the same as that recommended for adults. The dose of RIG for PEP is based on body weight which will be decided by your doctor.
Reactions (side effects) from the rabies treatment are rare, but may include the following:
A slight rise in temperature (1 to 2 degrees above the child's normal temperature).
The places where the shots were given may become red, swollen and itchy.
If either of these symptoms occurs, your doctor can treat them. So don't worry.
Q: Why is an opinion bad in science?
Krishna: Science is based on facts. Opinions need not be based on facts. They usually are based on biases and strange perceptions of a situation.
Recently when I said 'ancient medical systems are un-reliable', one person said my 'opinion' 's wrong. What the person didn't understand is - when people of science speak, they simply don't express their opinion. They base their expressions on facts and evidence. Like this ...
This is what a liver transplant surgeon told me recently...
Q: Recently I read a story in the news papers here. According to the story a car hit an electric pole at high speed and the high tension wires fell on the car and when the people inside tried to come out of it, they got electrocuted. How can we save ourselves in such situations?
Krishna: In such situations usually people panic. But car tyres are made up of rubber and will work as an insulator. The metal surface of the car acts as a Faraday cage due to which the electric field inside the car is zero. There is no need to panic. It would be better to stay safely inside a car till help arrives. You should also make people around alert so that they don't touch the car. If your car is still working, then slowly drive the car away from the power line until it falls off your car and you're well clear of it. If you come across a power line on the ground then stay away. It is possible to get electrocuted because the voltage fans out from the wire before going down into the ground.
If the car is not working, and when there is fire, one should not step out of the vehicle in such cases without taking precautions, if you do so you will complete the circuit between wires and earth and you’ll be fried in no time. What is safe to do is pick up the floor mats in your car and throw them on the ground where you could reach by jumping, make sure you cover maximum area with mats, then open the car door widely ( roof top is preferable) then jump onto the mats which you placed earlier. Make sure you remove two legs at once( keeping one leg inside may complete circuit). Don’t walk over there just slide your feet like jam over bread( you need greater knowledge in physics to understand this). Make sure that you jump completely free of the vehicle with both feet together to avoid contact with the live car (metal) and the ground at the same time. Once you jump from a car with a power line on it, the danger may not be over. Electricity can spread out through the ground in a circle from any downed line. Hop as far away as possible from the vehicle keeping both feet together. Do not try to help someone else from the car while you are standing on the ground. If you do, you will become a path for electricity and could be hurt or killed!
The difficulty in actually implementing this safe procedure successfully can be surpassed only when one has complete knowledge of physics, electricity and bio-mechanics. Hmmm! So learn these things! Science helps you. Sure it does. But only if you make it your pal!
Q: What is the difference between a heart attack and a cardiac arrest?
Krishna: A heart attack occurs when the blood supply to part of the heart stops and thus causes a section of the heart muscle to begin to die. A blockage or narrowing of the coronary artery cuts off or reduces blood flow to the heart, causing damage due to lack of oxygen.
Symptoms: chest pain, fatigue, weakness, nausea, difficulty in breathing.
A cardiac arrest occurs when the heart stops beating as a whole. The heart stops beating abruptly, either from a malfunction in the heart's electrical system or another sudden change in the circulatory system.
Symptoms: collapsing, becoming unconscious, not breathing, no pulse.
Citations:
[1] http://www.cancer.net/research-a...
[2] Medications That Cause False Positive Pregnancy Tests
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