What are the dangers of hypnosis?

What are the dangers of hypnosis?

Hypnosis can help with anxiety, although sometimes the thought of going to a hypnotherapist can make them anxious. However, they have nothing to be nervous about if they go to a properly qualified person. Among professionals, we always say that someone shouldn't treat someone with hypnosis if they wouldn't be competent to treat it without hypnosis. With an anxiety problem, you would probably be thinking about going to see a psychologist. If that psychologist knows how to do hypnosis, he may think about using that as an additional tool. This can help with the effectiveness of the treatment normally given. There is nothing harmful about hypnosis in itself as long as you go to someone properly qualified.

How does something like radiotherapy treat prostate cancer?

How does something like radiotherapy treat prostate cancer?

There are three ways of using radiotherapy: one is something called x-ray beam radiotherapy where x-rays are fired at a target. Another way is brachytherapy where a radioactive source is put in a tumour, and the third way is injecting a radioactive substance like radioactive iodine, which treats thyroid cancer. The reason it destroys the cancer is due to the way the radioactivity interacts with cells and causes DNA damage. It's specifically the ionising radiation that we use because the interaction with the cell causes electrons to be given off and leaving cells that are ionised. Usually when x-rays or gamma rays interact with the body, they actually interact with water and that water can form free radicals. The free radicals can cause damage to the cells by damaging the DNA.

Does eating chillies help with neuralgia?

Does eating chillies help with neuralgia?

It's not the actual eating of the chillies. The thing that makes chillies hot is called capsaicin. Not only does it make things taste hot but can also be used as a topical ointment on the skin if you have various pain syndromes. One of those is shingles. If you've had chickenpox in the past then you have chickenpox living in your nerve fibres in your body for the rest of your life. Periodically it can come back out and cause a patch of chickenpox vesicles or blisters on one patch of skin. After they go away, it can be tremendously painful. However researchers have found that if you apply this capsaicin to the painful area, it can actually help to relieve the pain. This could possibly be because pain is mediated in the nervous system by a class of tiny nerve fibres referred to as C-fibres. Capsaicin activated those nerve fibres and in some cases activates them to death. This turns them off and indirectly makes them less sensitive, which is why the pain goes away.

Is it dangerous to live 500 metres away from a mobile phone mast?

Is it dangerous to live 500 metres away from a mobile phone mast?

It's far less dangerous than using the phone yourself. No one's actually found a dangerous relationship with using a phone. When you use a phone, that transmitter is a couple of centimetres away from your head, and the strength of the signal goes down with the distance squared. So it's going to be thousands and thousands of times weaker than your mobile phone right next to your head.

To explore the science of this - if you look at the energy of a microwave, and the reason we have these things in our kitchen and cook with them and we are happy to put a microwave source or a mobile phone to the side of our heads, is because the energy in the wave of a microwave is not sufficient to break chemical bonds in the same way that an x-ray or a gamma ray, or more intense forms can. And therefore they're viewed as non-ionising forms of radioation, and are viewed to be safe. That said, there's no evidence that if you do expose your nervous system to these things that they won't have a temperature effect; because we think that they might warm your head up a little bit if you're exposed to a phone. But of course the mast is much further away than a phone is. But also, exposing tissue to microwaves for long periods of time may or may not have some sort of growth related effect.

Certainly in terms of cancer there isn't enough energy in phone radiation to damage DNA which is the ultimate cause of cancer. Virtually all the studies that have been done have not found a significant link between mobile phone use and cancer. The one thing we don't have is really long term data and that's hopefully coming in in the next couple of years. But the studies certainly haven't found an effect in terms of cancer.

Is it safe to swallow chewing gum ?

Is it safe to swallow chewing gum ?

Chewing gum used to be from a rubber plant, but is now artificial. It sticks to the road because it contains long oily polymer chains which are chemically similar to some of the constituents of the road surface. It's very hard wearing stuff and doesn't get digested when you swallow it. It can cling onto the sides of your intestines and distort the gut, are occasionally trigger a dangerous disorder called intussusception where the gut telescopes inside itself, although this is rare in adults. It would be better for the environment if people could swallow it. Until then, it would be good to develop a family of chewing gum-consuming bacteria that could eat it off the pavement !

Why don't spiders run out of silk?

Why don't spiders run out of silk?

Spiders are really actually quite clever. Ancestrally they go back a couple of hundred million years, we think. They have glands at the back end of the spider and now it turns out also on their feet that make silk. And what scientists think, is that the glands on the back of their abdomen that make silk are just adapted limbs, where they used to have some legs. Silk is the reaction of proteins. So you have a chemical reaction going on at the back end of the spider that literally spins silk on demand. The spider eats something that has got protein in it. So when it goes and catches something in its web, it injects a venom into that insect that kills it by paralysing it. The insect is paralysed and doesn't die instantly so it remains fresh, the spider injects digestive juices which liquify an insect. And because an insect is like a husk, with a hard skeleton on the outside with the soft bits in the middle, the spider can literally suck the good bits out of the inside leaving behind a dry, wizened up shrivelled skeleton. That's why you see these sort of husks of insects left under spider webs. All the protein and goodness from inside the insect ends up inside the spider, the spider digests that, absorbs it, and then the proteins go to the back end of the spider. And they get turned into new web, amongst other things a spider needs to make. And some spiders have taken this a step further. What they've done is to make the process even more efficient, by eating their own web. This doesn't do them any harm because web is just protein. By eating their own web they're getting the proteins back into their body and they can then reuse them. Spiders' web is incredible stuff and it can absorb immense amounts of energy. It's got the tensile strength of steel. Scientists are now looking at ways of using it for bullet-proof vests, for example. If you can make this artificially in enough quantities you've got something with the tensile strength of a piece of steel, and the ability to stop bullets much better than a bullet-proof vest. Which means rather than police having to go around in these very thick outfits which restrict movement, if you could make it out of spider silk it would be a) lighter, b) a breatheable fabric, so it wouldn't make you so hot and uncomfortable, and c) it wouldn't restrict your movement so much.

How are seedless grapes grown?

How are seedless grapes grown?

The correct answer is that the plants that grow them are actually clones. So instead of growing them from seeds, they're grown from cuttings, so from existing plants. So obviously the first seedless grapes were a plant that arose through mutation, that means that they don't have seeds. And some growers must have noticed this. And you can basically take a little shoot or a stem off the plant, dip it in rooting powder, put it in the ground, and a new tree will grow. This is how a lot of plants are cultivated now, and also a lot of seedless varieties. It's causing problems now with bananas though. Because they're all clones, they're getting struck down by funguses and things. If a population is genetically identical, it can very easily be wiped out because it has the same resistance to different pathogens.

Does drinking too much milk, or calcium, reduce your physical endurance or stamina?

Does drinking too much milk, or calcium, reduce your physical endurance or stamina?

If you drink milk that isn't skimmed, it's got lots and lots of fat in it. Having lots of fat isn't good for you because of the calories, but also because it furs up your blood vessels. Milk is also very rich in calcium which, in people who are prone to stones, can deposit in the kidney and cause kidney stones. And the other side effect of milk that not many people know, is if you have irritation to the stomach lining and you're at risk of getting stomach ulcers, calcium is used as a co-signal by the wall of the stomach to produce acid. If you have calcium levels in the blood going up, you make more acid. Some people think when they have a dodgy stomach that drinking milk will settle it. When you first do that your stomach feels happier because you've given the acid something to eat other than the wall of your stomach. But then the calcium is absorbed and goes into the blood stream and increases the amount of acid your stomach makes, causing a vicious cycle.

Does peanut butter help to lower your cholesterol?

Does peanut butter help to lower your cholesterol?

eanut butter is a source of mono-unsaturated and polyunsaturated fat. So in the context of a balanced diet, it is likely to have some beneficial effect if you are at the same time cutting out saturated fat. So it's really about replacing say the amount of red meat you might be eating with things that are rich in vegetable fats. Another good example of this would be Soya beans. Soya beans are a good source of vegetable fats.

Everybody knows that salt melts ice. Why are there such big icebergs in the sea?

Everybody knows that salt melts ice. Why are there such big icebergs in the sea?

Salt makes ice melt at a lower temperature. So in sea water ice will melt at maybe -5 or -6 degrees centigrade. But if you get cold enough, the water will still freeze. And so you can still get icebergs. It's just got to be a bit colder than if it was in a lake. When there's salt in water, the water can get a bit lost in the salt. It gets in the way of the water forming a crystal. It's more difficult for the water to form the crystal, so it has to be a bit colder for it to actually freeze.

Could sound waves be heard on Mars?

Could sound waves be heard on Mars?

There are two questions here. One is if we had a very loud screaming baby on the Earth, would somebody on Mars in theory hear the baby screaming, or would you need to have some interplanetary baby monitor? The answer is no, you wouldn't be able to hear the sound from Earth on Mars because the space in between Earth and Mars is a vacuum. There's a wonderful experiment you can do where you put an alarm clock under a bell jar and you start a vacuum pump going. You then stop hearing the bell even though the bell is still going. But then the question is, well what if your baby was in the bedroom in your Mars planetary home? Would you be able to hear the baby crying from downstairs in your bedsit? The answer would depend very much on the atmosphere on Mars and my understanding is that there's not very much atmosphere: about 1% of the atmosphere on Earth, so it's getting close to a vacuum. So there are two things: the amount of energy that you can pump into the atmosphere is less; and also the speed of sound would be a lot faster.

Does the sun affect the tides like the moon?

Does the sun affect the tides like the moon?

Yes, but to a lesser extent than the moon, which is the main determinant of our tides. You can work out if we are on a neap tide or a spring tide - that's a high tide or a low tide - depending on whether these two celestial bodies line up with each other. When the sun is in alighnment with the moon we have a new moon (which means you can't see it because it is not illuminated and is dark) and the two bodies work together gravitationally, producing a spring tide. Two weeks later, however, the moon is at 90 degrees to the sun, so they're not in alignment, so you have a neap tide. Two weeks after that you have a full moon and the two are working together again, and you have a spring tide.

Why is it helium in balloons and not hydrogen?

Why is it helium in balloons and not hydrogen?

In order to get a floating balloon you want a gas which is as light as possible. Helium is quite a lot lighter than air weight. It’s about and eighth of the density of air. Hydrogen is about a sixteenth the density of air. So it’ll float in air and will even float upwards. You’d have thought that hydrogen would be a better gas as it would give slightly more lift than helium because it’s lighter. This is true. The problem is hydrogen is explosive and if you have children running around with balloons that could catch fire and blow up in their faces, it may have some health and safety implications. The other thing is that although hydrogen is half as heavy as helium it doesn’t give you twice as much lift because the amount of lift you get is in its difference in density with [respect to] air. It’s actually only another sixteenth of the density of air. It’s a little bit better but not very much, so it’s not worth the danger.

Helium is quite expensive, though, because it’s a limited resource here on the planet. It's only created by radioactive decay on Earth. Atomic nucleuses emitting alpha particles that are actually helium nucleuses. They slow down and gain some electrons and turn into a helium atom. It tends to be found in oil wells where you get a gas-proof layer of rock above a load of rocks containing radioactive elements. They break down to helium. It floats up and gets trapped, often at the top of an oil well . The amount of helium that we can access cheaply is very limited because not all our oil wells have it.

What happens when a bomb explodes underwater?

What happens when a bomb explodes underwater?

Well when any bomb explodes the first thing you're going to get is a lot of high-pressure gas because you've taken a load of solid and turned it into gas. It wants to expand. Water isn't going to move away nearly as quickly as air does. The pressure's going to remain very high, pushing water away. The fastest the water can move away is roughly the speed of sound in water. That's 1400m/s. You're going to form a bubble. As that water is pushed away very fast you're going to get a second powerful sound wave or pressure wave moving away from it. If the water doesn't compress that's going to have a very high pressure and do a lot of damage which is why depth charges can destroy strong things like submarines, even 10-20m away. Apparently it's way that there's a theory of how you might be able to blow up safes. If you fill a safe with water an drop a small charge in then because the pressure change is so much greater it might blow the door off.

Why do babies get jaundice when they are born, and why does a session on a sun bed help get rid of it?

Why do babies get jaundice when they are born, and why does a session on a sun bed help get rid of it?

Babies are not actually born yellow; it develops when they are first born. Every minute we make lots of red blood cells to replace those that have worn out. When old red blood cells are broken down, a yellow-coloured waste product, called bilirubin, is produced. Bilirubin is insoluble in water until it is metabolised by enzymes in the liver which add sugars to the molecule to help it dissolve meaning that it can be excreted in bile, and in urine. However, a developing baby doesn't need this biochemical pathway for metabolising bilirubin until it is born, because the mother removes the bilirubin via the placenta. But when some babies are first born and can no longer rely on their mother to help remove bilirubin for them, particularly if they are premature or have liver problems, there can be a delay in switching on this metabolic pathway and a backlog of bilirubin builds up around the body, making the child yellow. Because , until it is metabolised, bilirubin is insoluble in water but dissolves very well in fats, it accumulates in the skin, where we store most of our body fats, explaining why the babies appear yellow. If it is allowed to continue for a long time, jaundice can cause permanent damage to the brain, but if the baby is put under a blue light, a photochemical reaction occurs, breaking up the bilirubin and making it water soluble. This allows the baby to excrete the excess bilirubin in its urine. The process was discovered accidentally by Judith Ward who used to take babies into sunlight because she thought it was good for them. Having returned them to the hospital, she found that a previously-jaundiced baby had normally-coloured skin on sun-exposed areas, but yellow skin where the nappy had been. As a result the method was quickly adopted for the treatment of neonatal jaundice.

What ingredients go into antibiotics, and how do they work ?

What ingredients go into antibiotics, and how do they work ?

Tablets taken by mouth contain a lot of the actual antibiotic. They also contain lots of other substances which enable the manufacturer to produce a tablet that can be kept in packets and are easy to swallow. For example, the smooth outer coatings of some tablets are often made out of vegetable products. Once the tablet is in your stomach, the active bits distribute around the body through the bloodstream, reach the site(s) of infection, and kill the offending bacteria. There are three different ways antibiotics kill bacteria. Some stop bacteria from growing by stopping their protein production; others stop them from making chromosomes; and the third type stop bacteria from making cell walls. Without a proper cell wall, the bacteria explode and die.

Which bacteria or viruses cause ear infections ?

Which bacteria or viruses cause ear infections ?

The ears have the same linings and are connected to the nose and throat through the eustacian tube. This means that any of the viruses that cause colds and sore throats can get through into your ears. Viruses are the main invaders, but bacteria can cause secondary infection. They seize the opportunity to invade after a virus has caused the initial problem - such as damaging the protective lining of the airway, or blocking up the eustacian tubes in your ears with mucus

Are fizzy and sweet drinks addictive?

Are fizzy and sweet drinks addictive?

Coca Cola, most other fizzy drinks and cold remedies contain huge amount of caffeine. This is a legal drug that gives you energy and perks you up. This is why taking certain 'flu remedies make you feel more awake and generally much better. These are similar effects to those found when drinking coffee. There are specific receptors in your brain for caffeine. These interact with a part of the brain that uses the reward-chemical dopamine, the same system activated by drugs such as cocaine. Although caffeine and cocaine don't give the same kind of rush effect, both have a common mechanism. It's also worth bearing in mind that tea also contains a lot of caffeine.