1

Physiology & Medicine / Can a person contract cancer by eating it?

« on: 27/07/2011 02:14:42 »

Cross species transmission of cancers would be very low, and as Supercryptid mentioned, the tissue would have to be very very fresh (live).

Biologists do infect rats with Human cancers (through surgery).  However, it is only possible to do so with seriously immune compromised rats called "Nude Rats".  Otherwise the natural immune response would be to fight the foreign tissue.

Potentially AIDS patients, transplant patients, or other patients with serious immune deficiencies would be at higher risk.

This brings up a couple of points.  If a person has cancer, or a history of cancer, then they would be automatically excluded from being an organ donor.  Since cancer can spread in the blood, then even unaffected organs would be excluded from transplant.  Likewise, it would be bad for a cancer patient to donate blood.

HPV is a highly communicable viral disease that that carries the risk of developing cervical cancer.  While men can be carriers of the virus, the cancer risk is believed only to be in women.  However, the transmission is likely just creating an environment where cancer can develop, without transmitting the cancer itself.

HPV has been recently linked to some kinds of cancer in men, especially oral cancers.

Oral cancers have seen a sharp rise (in both men and women) in the last 30 years, especially in young people. It's thought this might be because oral sex is considered safe sex (as far as AIDS goes).

2

Physiology & Medicine / Can a person contract cancer by eating it?

« on: 27/07/2011 02:09:42 »

Cross species transmission of cancers would be very low, and as Supercryptid mentioned, the tissue would have to be very very fresh (live).

In an effort to acquire the freshest meat possible I once tried to eat a living cow, but it made so much noise the rancher came out and chased me away.

3

Physics, Astronomy & Cosmology / What is spinning in a spinning black hole?

« on: 27/07/2011 02:01:36 »

according to Relativity the perception of time, how long it takes for a second to elapse, depends on the relative velocity of the observers. Two people travailing at different speeds will not agree on the amount of time that has passed. This is also true of gravity.  A person standing on the surface of the moon will not agree with a person standing on Earth as to how much time has passed. Though it will take a very long time for them to notice the difference, the event horizon of a black hole has a much more powerful gravity field. So powerful that an observer at the event horizon would never say "when", as viewed from Earth, to signal the elapse of his first second. From that idea there should be no observable spin from outside the black hole.

This is just my own theory, but I imagine that if we were able to see below the event horizon of the black hole we'd see the surface of the star that collapsed to form it, still slowly (to us) collapsing. Should you decide to try and find this star you won't though. Assuming you can get passed the stretch you'd cross the event horizon after the star's surface, so you won't see it. However your own time perception will be slowed down. If billions of years later someone comes along and looks in they'll see you, still there just above the surface of the star.

4

Plant Sciences, Zoology & Evolution / Do African-Americans differ from black Africans?

« on: 27/07/2011 00:56:24 »

A science story I heard recently described a genetic "redistribution" map made of African-Americans (a term I happen to HATE especially when it's applied to people who are not American, like Naomi Campbell or Noel Clarke) that mapped out how genetic changes are made during sexual reproduction. The story mentioned that there were differences in this map from a map made of Europeans.

Considering that almost all African-Americans have quite a lot of European ancestry it got me to wondering what differences there are between African-Americans (and Europeans of largely African ancestry) and black Africans.

The blackest person I ever knew was the mother of some childhood friends who had grown up in Uganda. Her husband was American (and white) but she was as black as coal, and quite beautiful (her daughters were jaw droppers and about the color of coffee with 2 creams). It was odd for me as a kid. She didn't speak like a normal black person, rather she spoke with a very proper English accent.

5

Physiology & Medicine / Can a person contract cancer by eating it?

« on: 30/05/2011 06:08:44 »

I'm not talking about deliberately eating a cancer tumor, but if a person eats meat that happens to contain a carcinoma can that cancer be transferred to the person?

I know that sometimes a tumor can shed cells that can spread the cancer to other parts of the body, but can this happen from an animal to a person (I'm assuming that the person is not a cannibal) from say a cow or pig, or even a bird?

6

Physics, Astronomy & Cosmology / What is spinning in a spinning black hole?

« on: 30/05/2011 05:39:35 »

Very often on NS they've talked about spinning black holes. A black hole is not an object in the way a planet or star is, rather it's a region of space so highly curved that it is curved back on itself, so what, exactly, is spinning?

7

Physics, Astronomy & Cosmology / How heavy was the Heavy bombardment era?

« on: 20/04/2011 00:30:39 »

the late heavy bombardment era is referred to as the last growth spurt of the Earth, when asteroids rained down on Earth fairly often. TV shows typically depict this time as objects striking every few seconds, but this is surly an exaggeration, much like 18th and 19th Century paintings of battles showing quite a lot happening all at once.

If I were to visit Earth during this time how often could I expect to see an impact, every fey days, years or would it be more like every few thousand years or millions of years?

8

Physics, Astronomy & Cosmology / How do they measure very low levels of things?

« on: 19/04/2011 23:55:14 »

All radioactive decay is very characteristic and given the right sort of equipment the type and energy of the radiation can be detected with great precision this allows precisely the sort of atom that emitted the radiation to be identified so for example individual atoms of a short lived fission product can be identified as they decay.  There is no other natural source of such short lived isotopes so individual atoms getting to the UK in the air from Japan can be identified.  As there are an incredible number of atoms in even a small quantity of material the test is just about a sensitive as a test could possibly be.

Remember the story that if you managed to distribute a glass of water through all the water on the earth any glass of water would contain one hundred of the atoms in the original glass.

I think I read in a Tom Clancy book that after a nuclear bomb was detonated they were able to tell where the bomb came from by testing the radio active signature of the fuel. But then Clancy had Jack Ryan referred to, in England, as "Sir Jack" (he was knighted for saving members of the Royal Family from a terrorist attack). This is improper as only British subjects are allowed to use the title "sir", though non-British knights are still able to use the letters after their name.

Even Bob Hope (KBE, KCSG, KSS) who was born in England but became a US citizen could not properly be referred to as "Sir Robbert" or "Sir Leslie" his real first name.

9

Physics, Astronomy & Cosmology / How do they measure very low levels of things?

« on: 19/04/2011 23:43:05 »

They put sample (the grain of salt or seawater) and detector in a big lead box to get the readings - at least that is one method.

I suspect the grains of salt in question were more metaphorical than physical.

Indeed. The news media typically gets things wrong. My father worked for 30 years at an oil refinery where he witnessed a great deal of accidents that were reported on the news. The media's score on accurate reporting was a big whopping 0.

10

New Theories / Does the future already exist?

« on: 14/04/2011 02:12:48 »

boy meets girl, they click, they have kids. But that was after boy meets girl,  they didn't click, they didn't have kids, so the future was moulded as soon as they split up after the first date. Their two kids tom and anne were never born....whereas after the click,  fred and sue were born...

Both histories exist in the same way that two different corridors exist in a maze.

In the 1930's Neville Chamberlain came to a split in the maze. one led to war, the other APPEARED to lead to piece. Unfortunately for the world Chamberlain decided to take the piece corridor, which turned out to lead to a war much worse than it should have been. This is the history we know and "remember". But the history in which Chamberlain lead the Allies to remove Hitler before he became too strong also exists down another corridor.

11

Radio Show & Podcast Feedback / Water baloons and fire?

« on: 13/04/2011 09:09:16 »

Loved the kitchen science this week! The question was asked "Can this be done with other things?" Well as a welder I can tell you it's done all the time.

There is a welding job that might seem completely crazy to anyone not familiar with how this works. Oil refineries have a lot of pipes that transport highly flammable things under very high pressers. These pipes tend to wear from the inside out so you could have a pipe that looks fine but has become extremely thin. It can be very very expensive to take the pipe out of service to replace it so a temporary fix has been developed. You take a section of pipe that has an inside diameter equal to the outside diameter of the pipe to be treated. You cut the pipe in half then place the two halves over the old pipe and weld it up. But here's the thing. This treatment must be welded "to code" (very important rules that say how the pipe must be welded and inspected to insure it doesn't fail) as if it were a new pipe. The seam of the new pipe (the two halves) must be welded to the old pipe, which may already be very thin.

If the product in the pipe is stationary this would be a problem. As you heat the metal it gets weaker (like in the Twin Towers) which would cause a failure (almost always fatal to the welder, and IF survived he or she will wish they hadn't). But if the product is flowing then that product will carry away excess heat so the pipe will not fail.

I have won camping bets by saying I could boil water in a paper cup in the camp fire. You take a paper cup and carefully place it DIRECTLY into the flames. The paper in the cup will burn to the water level, then the cup will very slowly burn down as the water boils away. This will NOT work with a polystyrene cup as the polystyrene insulates very well. Also once the water is boiling do not attempt to remove the cup. It will be filled to the very top with boiling water. If your fire burns long enough the water will boil away and burn the cup. If you extinguish the fire before the water is gone just knock the cup over.

12

Physics, Astronomy & Cosmology / How do they measure very low levels of things?

« on: 13/04/2011 08:52:05 »

A few weeks ago the TV news reported that Radiation from Japan had been detected here in Portland, Oregon. Large grains of salt being considered, they showed a graphic which showed the levels detected compared to levels of concern. I don't remember the units used but the level of concern was 25 and the level detected was .0000008 which is very far below even the natural background.

My question here is how do you measure something that is so far below the background. I haven't done the math but it's got to about like trying to hear a whisper (30 dB) next to an F-16 in full afterburner (well over 160-180 dB loud enough to cause instant hearing loss anyway).

13

New Theories / Does the future already exist?

« on: 06/04/2011 02:56:05 »

Now one twin decides to go on a short trip at 90% C. That twin trades some of his time velocity for space velocity to move away from his twin. Now they are NOT both moving through time at the same velocity

I'm not sure I understand you properly, but are you implying then that time is not relative, but there is some sort of absolute standard of time? And one of the twins is going faster than the other, rather than just relative to each other?

Newton thought there was such a thing of absolute space and absolute time. For two about 300 years this was debated ad nausea without much progress. One camp held that space was a real physical thing on which matter was placed. Think of a stage play. The actors move about the stage doing things and saying things, but when the play is over and the actors go home, and they take down the set the stage still exists. The other camp argued that without matter there would be no space. Think of an alphabet. I can say that that I is four letters down from D, that other letter E, F, G, and H are between D and I but without the letter (matter) then there is no such thing as space. Newton also felt that time was absolute. That an hour in London is an hour in Detroit and in the moon and any other place.

Basically motion needs a reference point. You see a sign on the side of the road that reads "speed limit 100 KPH (or 60 MPH)" but 100 KPH relative to what? Motion through space needs to have some sort of reference to have any meaning.

There is however absolute space-time. This is why we can say "moving through time".

In American Football the player must move the ball 10 yards down field to get a "first down" before being tackled. A running back who can run at a speed of 3 feet per second (about 5 MPH) should be able to reach the first down marker in about 10 seconds. He takes the snap and runs for 13 seconds before being tackled but is still short of the first down, why? He ran cross way down the field so he did run more than 10 yards but much of that 10 yards was used running to the sideline. In the same way, if you want to move through one of the 3 spacial dimensions you'll need to move crosswise to the time dimension which means it will take a little longer for your hour to pass.

14

Marine Science / Re: Can antibiotics affect sharks?

« on: 06/04/2011 00:50:46 »

I would think it would depend a lot on the antibiotic. 

For example, a natural antibiotic such as Penicillin is found in molds, and the kinds of things that a scavenger might eat, so it might not be surprising to find Penicillin resistant flora in the sharks.

However, for other types of antibiotic resistance, one would have to come up with a plausible mechanism for it to enter the shark's food chain.

For example.  If a fish farm fed salmon smolt antibiotics, then the salmon might develop antibiotic resistant bacteria.  Then, if these smolt were released into the ocean, sharks might eat the fish and be colonized by antibiotic resistant salmon bacteria.  Through the wonders of plasmids and gene transference, some shark flora might also pick up the resistance genes even though there might be little selective pressure to maintain these genes.

Another mechanism might be the release of untreated human sewage into rivers, streams, and the ocean carrying antibiotic resistant bacteria which could then colonize fish, and eventually colonize sharks. 

It should be possible to determine if the specific bacteria carrying the resistance began as human flora.

Many types of antibiotics are not found in the natural environment, and thus it would be unlikely that resistance to these antibiotics would develop without human involvement.

The reality is that this poses little danger to the sharks themselves, but could eventually lead back to us in that standard antibiotics could loose effectiveness.  Most of the multi-drug resistant bacteria are limited to the hospital setting, but eventually might increase in prevalence outside of the hospital setting.  The use of things such as antibacterial soaps should be limited only to those few situations where they are required.

I would think that fish farmers would only very rarely dump there fish into the ocean. The number of fish in the ocean that came from fish farms is very very small.

Is far as sewage dumps, I suppose it's possible but again it will very quickly be diluted A LOT, so unless the shark is spending quite a lot of time hanging out by the outflow of these dump sites they won't be exposed to very high concentrations. Considering that sharks have "the entire watery globe to swim in" I can't imagine why they'd choose to hang out in sewage.

Again I don't think it's impossible for these resident bacteria to have come from humans, just quite a lot less likely than other sources. My issue with this was that natural sources were not even considered.

15

Marine Science / Can antibiotics affect sharks?

« on: 05/04/2011 08:43:49 »

I just started listening to Naked Oceans and in the very first podcast I found a story that bothers me quite a lot.

The story involved microbes discovered in sharks that are very resistant to antibiotics. The assumption was that this is a result of the human use of antibiotics, but I find it very hard to imagine how sharks from all over the planet could be coming into contact with human made antibiotics in concentrations high enough to effect their internal microbes. Isn't it much more likely (and interesting if) this is natural? Perhaps something in the shark's immune system is responsible. After all look what sharks do for a living. They attack and eat other fish or animals who usually have no wish to be eaten. They fight back and chances are they do some damage to the shark.

Not once was the possibility of a natural antibiotic property of these fascinating fish mentioned (I happen to love sharks). To be honest I'm getting a little sick of the homo-centric attitude of many of the sciences programs available. They'd have you believe that every single problem on Earth is caused by humans. It's not science, it's anti-science. It's a return to pre-Copernican thinking.

16

Plant Sciences, Zoology & Evolution / What species of caterpillar?

« on: 02/04/2011 18:36:54 »

Indeed it is a horn worm. Thank you all for your help.

17

New Theories / Does the future already exist?

« on: 02/04/2011 18:34:49 »

If every possible future already exists but it just depends which way we go, isn't that just another way of saying there is no future?

In this model past present and future need to be thought of a little differently. Instead of thinking of future events as nonexistent (say the President of the United States in 2112, who has not yet been born) you need to imagine time spatially. All events in time exists in space-time, just as both Indianapolis, In and Portland, Or both exists in different places. The flow of time we feel is US moving through time, not time passing us by.

This is why time dilation happens (google "twins paradox") When two objects (our twins) are not moving, relative to each other, both will agree as to how much time has passed. They are both moving though time at the same speed. Now one twin decides to go on a short trip at 90% C. That twin trades some of his time velocity for space velocity to move away from his twin. Now they are NOT both moving through time at the same velocity (velocity here differs from "speed" in that speed is scalar and velocity is vector) It's hard to imagine moving through time at any speed, because our definition of "speed" uses time itself (distance over time) but that's what we are doing, moving through time at near the speed of light.

18

New Theories / Does the future already exist?

« on: 30/03/2011 08:33:27 »

The book I'm reading right now has made the claim that the future already exists. The idea is that all of space-time (past, present and future) exists as a lump. The example given was a loaf of bread. Each location and each event are points within the loaf of bread. The events that happen at the same time according to two different observers depends on how they are moving relative to one another. This was given as an explanation of Relativity. So if one observer is moving near the speed of light he or she will say that two events happened quite a long time apart when two stationary observers will say they happened at the same time. This would mean that someone is seeing what another would call the future.

This bothered me because it seemed to suggest that the future is already set in stone precluding free will. The future is just as unchangeable as the past. No matter how hard I try I'll never prevent the launch of Challenger on 28 January 1986.

There is another theory I've never been comfortable with that my idea settles. The theory states that anytime something happens that has a chance of turning out in more than one way a new universe is created where all of the possibilities happen. I've never liked the idea of new universes popping into being every time someone decided between wearing the blue or the green shirt today.

But what if space-time was like a maze. One which you can not see what's ahead and you can only go one way. Reaching a dead end in the maze means your own end. When you decide to turn left or right in a maze you are not creating more maze, it's already there but you will never see that part of the maze you didn't take.

So in November 2012 I'll be faced with an intersection of maze where I can vote for Obama or whoever the Republican is. Down one corridor is a reality where Obama wins a second term and the other where the Republican wins. Both corridors exist but we'll only see the results of one.

I think you mean is there fate, are things set or deterimined(although detreminism has a few sides to it).

To a degree I would say yes. Speaking from a religious persepective, God gave man free will, which lead to the fall, and ultimately will express itself on the day of judgement, when people are to be assesed acording to their actions/lives, faith and apreciation.

It is said that God can see the future as easily as the past, therefore God knows what is to happen on the day of judgement, that however is God, no one else knows. Leaving us free still to adjust ourselves as we choose to, with in that reality certain things are decided by god to happen, other things are not nessecerily.

I way I like to see is like a road, you can drive on the left or the right yet certain things you will happen upon, which ever side you drive on. But that's a religious perspective and just one of many others.

to quote Jesus "For all your worrying can you add but a day to your life" Kinda like when the petrol runs out that's it, but I think how you drive could effect the condition of your car.

Peace.

I'm not saying there is fate at all. In my imagination time does not flow like a river, rather WE move through time. Imagine the maze has pictures on the wall that represent each instant. If I were to visit the part of the maze that corresponds to "England, early 1970's"  I might see Chris Smith being born. (I don't know what year he was born)I walk down the hall a bit and I can see him being chewed out for setting the cat on fire (again I have no idea if he ever really did this, but I'm sure he got into trouble for at least one thing growing up) A little farther down, say around 1990 I might find an intersection that represents Chris' decision to go to medical school. Down one path we'd see Chris earn an MD, start the Naked Scientists talking for years on the radio and giving lectures on virology. Other paths may lead us to see Chris flunk out of school, become a drug addict, get busted and spending years housed by the State. Both of these realities are just as real as the one Chris remembers, both are part of THIS universe, but Chris only remembers being a successful and talented radio personality because he CHOSE not to become addicted to drugs.

We are still free to choose in the same way that a person in a maze is free to choose their own path. Their is no "fate" because all possibilities exist already, until the end of time.

Just as we can see the past, so we can visit the "future" Perhaps down one path, in the year 2065 we'll find Chris, a very old man, explaining to his great-grand kids some scientific enigma, down another we'll see where Chris' intersects with some nutter who was fed up with his awful puns and knocked him off. Both futures are real, but which one he'll experience depends on not only his own choices, but those of all the nutters as well.

19

Plant Sciences, Zoology & Evolution / What species of caterpillar?

« on: 30/03/2011 08:10:44 »

No horn that I saw. I'll show him these pics tomorrow

20

Plant Sciences, Zoology & Evolution / What species of caterpillar?

« on: 30/03/2011 01:23:27 »

Can anyone please tell me what species of caterpillar this is? It's sky blue with black and white chevrons. It's large about as long as my finger. My friend thinks it's a Goliath caterpillar but I'm not sure. The picture of the Goliath was green, where this guy is blue. Please don't guess.