Wikipedia:Reference desk/Archives/Science/2007 April 23

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April 23

Automobile engineer

I want to do my M.S in automobile engineering.What is the best place in world to do it i.e institute?What is it's admission procedure? —The preceding unsigned comment was added by 210.212.215.141 (talk) 06:01, 23 April 2007 (UTC).

I'm not sure any universities offer graduate programs with that specific title. Perhaps you'd be interested in mechanical engineering if designing automobiles is your aim? -- mattb 14:09, 23 April 2007 (UTC)

Well, there is Kettering University, formerly General Motors Institute, in lovely Flint, Michigan (home to Michael Moore). StuRat 04:33, 24 April 2007 (UTC)

Actually a couple of universities in the UK offer Automotive Engineering as an MEng or MSc. For an MEng you have to study the entire course, which is 4 years. I believe Loughborough and Leeds universities both offer Automotive Engineering or Automotive Systems Engineering as 1-year MScs. Loughborough has a particularly strong reputation for engineering among UK universities. I don't think you can say specifically that one university or institute is the best place in the world for any particular subject. --YFB ¿ 04:44, 24 April 2007 (UTC)

Interval Running

I heard running 1 min on the treadmill and then walking 1 min, running 1min again, and walking over and over again is better than running strait, is this true? —The preceding unsigned comment was added by 76.167.136.84 (talk) 06:15, 23 April 2007 (UTC).

I believe that interval training is usually used to increase running speed. If you are strictly trying to burn calories, then you burn the most while you are running. 1 min running / 1 min walking would be a good way for a beginner to start with running as they may not be able to sustain a long period of running. So, if you are training for a quarter mile run, then 1 min running all out with 1 min walking rest would be a good interval training routine, or if you are out of shape then running and walking intervals would be a good way to build up endurance for longer runs with shorter walks. -Czmtzc 13:08, 23 April 2007 (UTC)

Blood Sugar

From what I understand, when blood sugar gets low, you get hungry, and when you have carbs, it goes up again and your not hungry anymore. So how are you not hungry if you only have protein and lets say salad? If theres no carbs, or very very little, how does your blood sugar rise? How are you no longer hungry? —The preceding unsigned comment was added by 76.167.136.84 (talk) 06:17, 23 April 2007 (UTC).

Satiety is the feeling of fullness and disappearance of hunger after a meal. Rockpocket 07:03, 23 April 2007 (UTC)

The basis of making a better diet pill? —The preceding unsigned comment was added by 71.100.8.252 (talk) 09:03, 23 April 2007 (UTC).

Blood sugar is not that direct a driver of hunger. A person may feel hungry when they see or smell tasty food, or because they are accustomed to eating at a certain time of day (even if they have had a large snack and should feel satiated). Hypoglycemia is a low blood sugar condition that is seen in diabetics when they have had too much medication, too much exercise, or not enough food, as well as in some non-diabetics, and it does not always produce hunger. Contrariwise, a diabetic may have extremely high blood sugar as a result of too little medication, too much food or endogenous factors which are not well understood, but may still feel extremely hungry, since the tissues are not able to process and use the sugar circulating in the bloodstream without sufficient insulin. Edison 16:31, 23 April 2007 (UTC)

Excercise

I was losing weight for a while on a reduced calorie diet (1200 calories a day, I'm a male, 180Pounds from 200 before) and weight training and cardio. Now I'm not losing weight anymore, and I can't figure out why. I tried changing my procedure (from elliptical to uphill walking on the treadmill) and its still not working. I usually do an hour of cardio 5 or 6 days a week. Is it too much to do 2 hours a day? Any other suggestions on what I can do? Thanks

It's possible that you're adding muscle in enough of a quantity that your weight isn't changing. In general, a specific volume of muscle weighs 4 times as much as the same volume of fat, so even though you're not losing weight, you could still be getting healthier by adding muscle. Dismas|^(talk) 10:30, 23 April 2007 (UTC)

I agree. You could be adding muscle to replace fat. That a look at your measurements. Waist should be going down while biceps and calves are going up. This would indicate that you were losing fat in the middle while building muscle in your arms and legs. Thighs could go either way depending on the starting fat content there. -Czmtzc 12:59, 23 April 2007 (UTC)

It's not possible to put on 3 pounds of muscle a week, thats what I was losing before, and especially with a highly reduced calorie diet and low protein consumption. I'm not even having protein shakes at the moment after workouts because the trainer said not to (but I am having amino acid pills twice a day). My measurements are not really changing either. —The preceding unsigned comment was added by 76.167.136.84 (talk) 15:46, 23 April 2007 (UTC).

It might be possible :) I gained an average of almost 2 pounds a week for a few months and probably did a lot less work than you are, and I tend not to eat much protein either :) HS7 13:09, 24 April 2007 (UTC)

We cannot give medical advice, so you should consult a physician and/or registered dietition for accurate advice on your weight loss program. That said, you did not say how long you had been on the weight loss program. Please be sure you have realistic goals for weight and fitness, and that your body image reflects objective reality as to whether you need to lose more. Your body fat percentage can be accurately measures. There is often a rapid initial weight loss (sometimes called 'water weight') followed by a plateau of no weight loss. This is when many people give up. Then eventually the slower pace of loss may kick back in. Edison 16:24, 23 April 2007 (UTC)

You may have triggered your body's starvation response. StuRat 00:03, 24 April 2007 (UTC)

Most guides I've read about weight loss often suggest about 4 workouts a week for a maximum duration of about 1 hour. Though often time estimates are in the ballpark of 40 minutes of continious cardio (running, cycling etc.). Even though I am not an expert in the field by any stretch of the imagination I might be able to give you some furhter adivice. Spread out your meals across the day. Most of us will have about 3 meals each day, turn it into 6 and you'll be using your intake alot more efficiently. Secondly look at what your burning up versus what you are taking in. If you take in too much then you'll gain weight, take in too little and your metabolism slows down. Simply put, you gotta eat to lose weight. PvT 09:45, 24 April 2007 (UTC)

Oil vs. Fat

Could you present to me about the similars between vegetable oil and animal fat?Mrleo88 07:13, 23 April 2007 (UTC)

The former is broadly considered a healthier cooking medium than the latter. The former smells less. The latter is rather difficult to acquire without butchering a corpse. Vranak

Excuse my pedantry, but these seem to be a list of differences, rather than similarities. ;) 213.48.15.234 12:58, 23 April 2007 (UTC)

Ha, oops. Yeah, they're both liquid, both used for cooking. Vranak

Actually quite a lot of animal fat is solid at room temperature. - Mgm|^(talk) 09:49, 24 April 2007 (UTC)

Sunflower oil and lard, the quintessential vegetable oil and animal fat, both contain palmitic acid and stearic acid (saturated fats), although lard has way more than sunflower oil. They both also contain sizeable amounts of Oleic acid, which is a bit better for you. Vegetable oil has also got masses of Linoleic acid, which is a really healthy polyunsaturated fat, while lard only has a tiny amount of this, which is entirely outweighed by all the really unhealthy sat-fats. Laïka 16:09, 23 April 2007 (UTC)

I could but I won't. Do your own homework... Nil Einne 22:27, 23 April 2007 (UTC)

Space Shuttle

What is the expected fate of the Space Shuttle? Can the Space Shuttle be converted for use as a Space Tourist vehicle by a conglomeration of multi-billionaires? Clem 07:17, 23 April 2007 (UTC)

The Space Shuttle is simply to expensive to use it. A place in a museum would be the fate, I could think of.--Stone 10:19, 23 April 2007 (UTC)

Since there are several Space Shuttles, they could end up in several museums. Or, if demand isn't adequate for all of them, some may be scrapped, with pieces sold off as souvenirs. StuRat 23:49, 23 April 2007 (UTC)

Sugar consumption

The human body will tolerate maybe a tablespoon of salt and maybe forty-three cups of coffee. Is there and limit to how much sugar the human body can handle before it does something expected or strange? 71.100.8.252 08:53, 23 April 2007 (UTC)

The LD50 for suggar is about 30g/kg Rat, upscaling to a human is 2-3kg for a human of 80kg. --Stone 10:17, 23 April 2007 (UTC)

So 2 kg of table sugar (sucrose) would have 4 calories per gram, right? This means the lethal dose (LD%) of this nutrient would be about 8000 calories for said 80kg person. What would be the mechanism of death? High blood sugar? Dehydration? People have died from excess water consumption, but has anyone ever died from acute sugar poisoning (other than diabetics)? Edison 16:19, 23 April 2007 (UTC)

Tests for LD50 on humans have been unpopular for quite some time and I habe this will be that way forever, but the osmosis and a low water coefficent will change a lot of reactions in the body. Salt is more toxic, because our nerve system needs it to generate the power for muscle contractions signals. —The preceding unsigned comment was added by Stone (talk • contribs) 16:58, 23 April 2007 (UTC).

Ocean Current Maps

I am a program assistant with the Kadena Air Base School Age program on Okinawa Japan. I have been trying to find ocean current maps that we can track tropical storms and typhoons. I would appreciate any suggestions you might could give me on where I could download or acquire these maps at a minimal cost. Our program runs on tight budget. I think the children would really like to be able to track these storms and see which ones might affect our island. Thank you so much for your time and I look forward to hearing from you. Paula Whited —The preceding unsigned comment was added by Pwtrekkie (talk • contribs) 10:41, 23 April 2007 (UTC).

Try this Ocen Currents. It is a search on Google Images for ocean current maps. -Czmtzc 12:49, 23 April 2007 (UTC)

However, I believe it's a mistake to assume that storms follow ocean currents only. This is one factor, but there are others, like winds, the jet stream, water temperature, water depth, coastal geography, interactions with other storms, etc. StuRat 23:41, 23 April 2007 (UTC)

True, storms don't follow currents, but currents can have a huge affect on storm systems. Warm currents can sustain and strenghten a tropical storm, while cold currents will kill them. If you know approximatly where the currents are, and predict a path of a storm over a current, you can make a prediction of weather the storm will strenghten or weaken. For instance, Hurican Katrina was so powerful because not only did they pass over the gulf stream near Florida, but there was a detached eddy of the gulf stream just south of New Orleans at the time providing a resevior of warm water in the northern Gulf of Mexico. This allowed the storm to remain extremely powerful until landfall. Usually tropical storms weaken a bit as they approach the NOrthern part of teh Gulf of Mexico. Czmtzc 12:22, 24 April 2007 (UTC)

HIGH PRESSURE GAS BOOSTING SYSTEM

Dear sirs,

I have made a high pressure boosting system for carbondioxide gas using gas booster, with various valves in loop. The system is able to boost the pressure to 350 bar with the needle valve in closed condition at the outlet of the system, but as soon as the needle valve is opened, to let the gas flow to an extruder barrel, the pressure drops, and then does not boost, unless the valve is again closed. Please advise in the matter, that is there any device which will assure me consitent flow output with high pressure.

Regards, from, Hitesh Modi

I see four approaches:

1) To reduce the pressure drop, ensure that the extruder barrel is under a pressure only slightly less than 350 bar. (You could completely eliminate the pressure drop by matching the two pressures, but then there would be no flow through the valve.)

2) Increase the size of the loop, so that the gas lost at the valve becomes less significant relative to the total and the pressure drop is reduced.

3) Reduce the size of the valve orifice. This will reduce both the flow rate and the pressure drop.

4) Actively increase the pressure elsewhere to compensate for the loss of pressure at the valve, by using a gas compressor or other device.

Depending on your constraints and requirements, you may elect to use some combination of all four methods. StuRat 23:33, 23 April 2007 (UTC)

Thanks, Mr. Sturat. Regards, from, HItesh Mody

atoms of same element with different atomic number

what is the term where atoms of same element have same mass number but different atomic number?

"something impossible", if that counts as a term. By definition, atoms of the same Chemical element have the same atomic number; that's what 'element' means. Atoms of the same element of different mass number are called different isotopes of the same element. Algebraist 14:03, 23 April 2007 Simon A. 18:55, 23 April 2007 (UTC)(UTC)

are you talking perchance of moles?

I suppose he is thinking of isobars, though this is not exactly what he asked for.

The name of an element comes from it's atomic number - so atoms of the same named element have the same atomic number (by definition) - all oxygen atoms have an atomic number of 8 - but their masses can be between 16 and 18. If you were thinking of atoms of an element that have the same atomic number but different mass - then you are thinking of "Isotopes". Basically, this is the way it is because the chemical properties of an atom are mainly determined by the number of protons and electrons (which is it's "Atomic number") - but there are often atoms with greater or fewer neutrons in their neucleus. Since the neutrons don't play a huge part in the properties of the atom, all that happens is that you get a different mass number. Historically, chemists named elements according to their properties - not according to their mass (which would be hard to measure accurately since most naturally occurring substances have a mixture of isotopes). SteveBaker 19:28, 23 April 2007 (UTC)

A couple nitpicks on the last response. While atoms of the same element all have the same atomic number, this corresponds with the number of protons only. The number of electrons may vary. While the number of electrons matches the number of protons in a neutral atom, ions can have (up to about 4) more or less electrons than protons. The number of neutrons doesn't change the chemical properties of an isotope, but can have drastic effects of the nuclear properties (radioactivity, stability, half-life) of the element. StuRat 23:17, 23 April 2007 (UTC)

Effect of putting a microwave on without anything in it

The other day I got out a meal to microwave then accidentally put the microwave on without putting the food in it. I've always been told that this is something you should never do: even if you are testing the microwave you should put a glass of water in it or something. What is the consequence of leaving a microwave on without anything in it? —The preceding unsigned comment was added by TomPhil (talk • contribs) 14:57, 23 April 2007 (UTC).

The magnetron (the high power vacuum tube that emits the microwave radiation) may over heat due to a lot of microwave energy being reflected back. Most modern microwave ovens will automatically shut down if the magnetron begins to overheat, but I wouldn't chance it. -- mattb 14:59, 23 April 2007 (UTC)

(edit conflict) take it from someone that has acctually done this out of courosity. Dont do it! i almost burnt the house down from this experiment and well basicly the bottom heats up. if its one of those rotating micros, the thing that rotates tends to be the thing to catch fire first. well like i said just dont do it, its not worth the risk. User:Maverick423 If It Looks Good Nuke It 15:04, 23 April 2007 (UTC)

This question was substantially answered here [1]

--88.109.36.120 15:12, 23 April 2007 (UTC)

biggest object in the universe

I noticed the actual largest thing in the universe was found last July [2] , but I can't seem to find a name for it. It's 200 million lightyears across and 12 billion lightyears away, but googling isn't helping me find a name for it, and it doesn't seem to be mentioned in 1 E+24 m, 1 E+25 m, or 1 E+26 m. Does anyone know what it's called? --128.113.149.154 15:01, 23 April 2007 (UTC)

The structure appears to be what's known as a Lyman-alpha blob, so named for its bright emission at the wavelength of the Lyman-alpha emission line. TenOfAllTrades(talk) 16:02, 23 April 2007 (UTC)

Solar power

What are the solar panels made with hydrogen called? DuctapeDaredevil 15:07, 23 April 2007 (UTC)

forgive me if i sound a little weird in saying this but arent they all called solar panels? also check out the solar panels article for more info User:Maverick423 If It Looks Good Nuke It 15:11, 23 April 2007 (UTC)

Do you mean something like this? If so, they're called tandem cells, and it's the panels that make the hydrogen, not the other way around. Laïka 16:02, 23 April 2007 (UTC)

What an unfortunate name for the inventors to choose... The phrase "tandem solar cell" has meant something different to semiconductor people for years. -- mattb 17:08, 23 April 2007 (UTC)

when do christmas trees die

when do christmas trees die? they appear to be alive when you buy them, as you still need to feed them water, but they are ultimately dead once they are cut off from the roots? so technically, when do they officially die? —The preceding unsigned comment was added by 128.175.20.122 (talk) 15:15, 23 April 2007 (UTC).

I doubt there's any official anywhere determining the moment of death; for plants, the moment of death is pretty nebulous anyway as you might be able to clone any still-living cell. But at our house, the Christmas trees are unofficially dead right about this time of year when the old Christmas tree gets removed from our deck near the bird feeders. You see, after its first function as a decorative holiday tree, it then performed much longer service outdoors as a shelter for the birds near the feeders. But we don't want them to nest in the now very-dry tree.

Atlant 15:44, 23 April 2007 (UTC)

As a doctor can tell you, death is a bit subjective. I'd say that if you put the tree in the ground and it never sprouted anything green, it was dead. Vranak

I would say it died when it was cut, because, I believe, a fir tree without the root ball is not going to recover. StuRat 23:02, 23 April 2007 (UTC)

I disagree. If you took a cutting from a branch tip a week after the tree was cut, you could grow an entire new tree from that cutting. So unless it 'came back to life' after it died, the tree could not have completely died at the moment it was cut down. Death is an arbitary point in a gradual process - it's not a black and white thing. SteveBaker 14:56, 24 April 2007 (UTC)

Bird in a cage

Suppose I have a budgie in a cage (or a seagull; it doesn't really matter) hanging from a spring scale, and I scare the bird so that it takes flight (without hitting any other part of the cage), would the force measured by the scale change? Furthermore, would it matter if the cage was airtight (ignoring the fact that the bird would suffocate!), so that all the air being displaced by the bird's wings remains in the cage? Laïka 16:01, 23 April 2007 (UTC)

I'll leave Kurt Shaped Box to answer for the seagull, but for the budgie, the scale reading would change, since the bird would exert force in whatever direction it flies. It wouldn't matter about the air because it would mostly affect other parts of the cage. I misread the question. I thought the bird was on the scale, not the cage. Clarityfiend 16:21, 23 April 2007 (UTC)

There are two boundary conditions to consider:

1. An aerodynamically-shaped perch in open air would lighten by the amount of the bird's weight when the bird flew off of it. Because the perch is aerodynamically-shaped, the downforce of air from the bird would have essentially no effect on the perch.
2. An unventilated cage would not change at all (because the bird must be creating a downforce of air roughly equal to the weight of the bird, and that downforce of air is impinging on the bottom of the unventilated cage.

The ventilated cage lies in-between those two boundary cases, but probably closer to the "perch" endpoint than the "unventilated" endpoint.

Atlant 17:31, 23 April 2007 (UTC)

[edit conflict] If the bird literally jumps off its perch, that will wobble the scale momentarily regardless of the ventilation of the cage (think dribbling a basketball onto a bathroom scale). Otherwise, if the cage is gossamer (bars as thin and as few as possible), the scale will read only the cage's weight while the bird is in flight (because the downdraft the bird is "sitting" on has very little effect on the cage). In a sealed (or nearly so) cage, the weight will not change at all aside from the initial wobble and absurdly small relativistic effects. --Tardis 17:54, 23 April 2007 (UTC)

Mythbusters investigated this (they were disproving the old joke of a guy driving a truck full of birds who would stop periodically and bang on the sides of the truck to make the birds fly around and reduce the weight of the truck). They found (not surprisingly) that it doesn't matter in the least whether the bird is flying on not - the weight of the truck is exactly the same. But it's not surprising. Newton's third law says that ever action has an equal and opposite reaction. So when the bird's wing pushes down on the air, that causes the air to push back - which increases it's pressure - which causes an equal force pushing down on the floor of the truck. So it makes no difference whether the bird is flying - the total weight is the same. That's OK for an enclosed space - for an open space, it's not quite the same - the air can escape off to the sides and such - so there clearly is a difference when you are talking about an open cage. SteveBaker 19:17, 23 April 2007 (UTC)

flight uses up energy, which would lead to the break down of glucose into water and carbon dioxide, and the loss of carbon dioxide, unless the cage is airtight. But really this is very much oversimplified. If the bird was flying continuuosly for a while, it might lose a small amount of weight in this way, almost enough to be measured.

Ferrofluid fridge magnet

My schoolmate asked physics teacher if ferrofluid applied to refrigerator would stick or would it fall down. The teacher didn't know, but it made me curious - can ferrofluid be used fridge magnet ? ---- Xil/talk 18:02, 23 April 2007 (UTC)

Nope. Ferrofluids are made up of nanoscale particles that exhibit strong paramagnetic behaviour. Unlike a ferromagnetic material, the (perhaps confusingly-named) ferrofluid particles will not retain the orientation of their domains in the absence of an external field, and won't stick to your fridge. On the other hand, you could stick a glob of ferrofluid to the fridge using a magnet. TenOfAllTrades(talk) 18:18, 23 April 2007 (UTC)

I agree - ferrofluids are influenced by magnets - but they are not themselves magnetic. All a ferrofliud is is a very fine metal powder mixed up in an oil or a polymer that's heavy enough to prevent the particles of metal sinking to the bottom. So slap the stuff onto a refrigerator door and you'll have a black oily blob slithering down the door - making a terrible mess as it goes. SteveBaker 19:09, 23 April 2007 (UTC)

Most likely one that is a permanent stain leading from the refrigerator door to the floor. [Mαc Δαvιs] ❖ 01:56, 24 April 2007 (UTC)

Just as I thought, Thank you for answers -- Xil/talk 18:17, 24 April 2007 (UTC)

300 more birthdays

hey, today *out of all the days lol* i was just wondering. what are the chances that science will grant us the technology to live an additional 300 years; *assuming it can be done* with like stemcell or whatever other means. and will this be possable sometime during my lifetime or is this kind of technology far away?. Lets not forget affordable. if this tech does come in my lifetime will it be afordable lets say a middle or lower class person? thanks for yout time User:Maverick423 If It Looks Good Nuke It 18:13, 23 April 2007 (UTC)

Let me consult my crystal ball. I'll get back with you in a few minutes with the answer to your question as well as the next set of winning lottery numbers. -- mattb 18:35, 23 April 2007 (UTC)

Since this question calls for an opinion, I've answered here: [3]. StuRat 19:06, 23 April 2007 (UTC)

There are lots of ways to say "No" - but those are obvious - maybe we just won't figure it out. But there are two interesting ways to answer "Yes" without invoking miraculous advances in medicine.

• I think that it's extremely likely that humans will one day start to merge with computers. We already entrust computers with memories and music and things that in the past would have been kept in our brains. It's not much of a stretch to imagine more and more of our intellect being moved into machines - and perhaps machines being grafted into our brains. If Moore's Law continues for another decade or two, we'll be able to build computers with enough computing power to accurately simulate a human brain. If we make the leap and leave our physical bodies to become bits and bytes then we can be 'backed up' and restored as often as necessary - there is no particular reason why our intellect would ever die. There would be many huge benefits to this life style - you could speed up the simulation and "slow time" - or you could slow it down in order to fast-forwards over boring things...interstellar travel at slow speeds would be no problem.

• I'm sceptical that 10 years will be enough for computers to be able to completely simulate a human brain. Even if they were technically capable which I'm somewhat doubtful, the software side is unlikely to be anything near there IMHO. Even 20 years seems abit soon. Note there is a difference between a computer capable of simulating a human brain and a computer capable of a human level of intelligence. While an ultra-intelligent computer could perhaps work out how to simulate a human brain, given that humans are only just beginning to really understand the brain, it seems unlikely a computer with human level intelligence will be able to work out how to that fast Nil Einne 22:57, 23 April 2007 (UTC)

and the second way is..?

OK - let's crunch some numbers. The articles brain and neuron don't entirely agree about the number of neurons and connections in the human brain - so I'm going to head out with numbers in the middle of their ranges. 500 GigaNeurons each with up to 10,000 connections per neuron - for a total of 10¹⁵ connections. We need maybe four bytes of storage to hold the state of a neuron - so 2,000 Gbytes of RAM would be needed to store the brain state - but that's dwarfed by the need to store where all of those 10,000 connections run to - that would need about six bytes per connection per neuron - so 30,000,000 Gigabytes are needed to store one human brain's current state.

Well, a 2007 PC can be bought with 16Gbytes - so we have to get 2 million times more RAM than a modern PC. With Moore's law working hard for us, that'll take 32 years. But that's to get the price down to the few thousand dollar range. If you were moderately well off - and prepared to sell everything you own to buy the machine, you could slap down a million dollars - and then it only takes 11 years to make that much storage capacity available.

Meanwhile, how about the compute needs? Well, for each of those 500 GigaNeurons we'll have to take into account the effect of 10,000 connections - so 5,000,000 Giga calculations will have to be done at whatever speed neurons fire. That's about once per few milliseconds...so let's say we need 5,000,000,000 Giga calculations per second. Well, a multicore 3GHz CPU can do a pretty complicated calculation 3 Gigatimes per second - so we just need a computer that's 5,000,000,000 times faster than we currently have. Well, we can spend our million dollars on it - to get something 1000 times bigger than we currently have - so we need a 5,000,000 times speedup in the core technology. That's gonna take about 33 years of Moores law.

But all of this assumes we're using a regular CPU - which isn't optimised for simulating neurons. If you look at a modern graphics card, it can generate pictures about 1,000 times faster than a general purpose CPU - even though it has about the same amount of circuitry...because it's specialised. So we can cut 10 years off our compute power schedule by assuming specialised circuitry...which gets us into the 20 year ballpark.

So - OK not 10 years - but 20 years. But this neglects the risk that Moores law will 'run out' before we get there. SteveBaker 00:24, 24 April 2007 (UTC)

It occurs to me that people might be surprised that we expect computers to get millions of times faster and have millions of times more memory in just 20 years. I thought I'd go back 30 years to the first microcomputer I ever used - an "Intellec-8". It had 4kbytes of RAM - my present computer has 4Gbytes (a million times more) - so Moore's law (which predicts that these numbers double every 18 months) has been exactly on track. The clock rate of that machine was 2MHz - but my modern PC is at 3.6GHz - only ~2000 times faster - but it can do a lot more on each clock tick and it has multiple cores and RAM caches and such - so in reality it's probably close to a million times faster. SteveBaker 14:51, 24 April 2007 (UTC)

• There is a possibility that a combination of the Many worlds hypothesis and the "Strong Anthropic principle" might mean that since there are an infinite number of parallel universes in which anything - no matter how unlikely - is happening in an infinite number of parallel universes. The anthropic principle says that the universe is the way it is because if it were any different then we wouldn't be here to observe it. That means that if there is any parallel universe in which you died - then you aren't in that one or you wouldn't be here to observe it. This would mean that all humans are (and have always been) immortal - at least as far as they are concerned. This is actually a very worrying thing - it would not mean that you'd live for a very long time as a healthy person - you might be forced to exist for ever in a really terrible state of existance in which you could only just bearly percieve your surroundings. I sure hope this fringe theory isn't true - but I have a horrible suspicion that it is!

SteveBaker 19:01, 23 April 2007 (UTC)

I think you are talking about Quantum suicide. Very interesting, but I don't know of anyone who's really tested it :) --Bennybp 20:41, 23 April 2007 (UTC)

Oh! But of course Wikipedia has an article about it! This is the very definition of "Hell on Earth"...and it's disturbingly likely to be true - although in most cases, the victim will be the only person to know it. SteveBaker 22:55, 23 April 2007 (UTC)

I found an even better link: Quantum immortality. Deeply worrying. Mommy - I'm scared! SteveBaker 23:36, 23 April 2007 (UTC)

Yea this one is one of the best i heard. merging ourselfs to computers, but it would worry me. computer viruses tend to corrupt and delete data, entrusting our memories , or even becomeing part of a computer, might cause more damage. but then again we can always have back up memory drives and stuff. Also mattb make sure those numbers are for the megamillion and dont forget the bonus ball =) User:Maverick423 If It Looks Good Nuke It 19:34, 23 April 2007 (UTC)

I agree - but I intend to run Linux on my brain (or is that "Run my brain on Linux"?) - so viruses will not be an issue! But the way brains work, they have an immense redundancy and fault tolerance - so long as the underlying simulation suite was heavily protected (eg by putting it in read-only memory), I think we'd be reasonably immune to such problems. But in practical terms, I'd imagine specialised custom hardware that optimally simulates a large neural network rather than running it on a general purpose machine. Such hardware wouldn't be programmable in the usual sense. But the idea of being able to slow down or stop my CPU clock and jump forwards through time - or fast-forwards through the dull parts of life is intriguing. Also, it would be possible (for example) to put a small computer on a tiny spacecraft and ship it off to the nearest star. Then when it gets there, send your brain to it at the speed of light on a radio wave so you can explore. You could also duplicate yourself quite easily...the possibilities are endless! The tricky part would be the peripherals though - interfacing robotics and sensors might be tough. SteveBaker 22:55, 23 April 2007 (UTC)

"Fast forwarding through the dull parts of life" was the theme to the movie Click. StuRat 23:55, 23 April 2007 (UTC)

Re: "Run Linux on my brain" -- I don't want to be forced recompile my brain to support the latest wifi hardware... I'm running my brain on OVMS. A little misunderstood, but it does its job so well that most people are unaware that it's doing anything! -- mattb 23:01, 23 April 2007 (UTC)

You want OpenVMS in your head?!? Wow! You are a brave person! Well, we at least agree that a BSOD would be no fun. SteveBaker 23:27, 23 April 2007 (UTC)

I kinda skirted the medical issue earlier - which makes me feel a little guilty. To attempt to answer the entirely medical question of whether our bodies can be made to keep running for 300 years or more - according to our article on longevity, the life expectancy of women is increasing at a rate of 3 months per year (men, a little slower). If the rate of medical advances was to increase fourfold - which could theoretically be done by training four times as many researchers and spending four times as much money - then it might be reasonable to assume that technology could extend our lives faster than we could live them - of course the question is whether it would be possible to continue that pace of development indefinitely or whether the technology required is simply out of reach for some reason - but perhaps at some threshold of technology, life spans become effectively infinite anyway. It has also been suggested that if we cracked the hardest problems in nanotechnology and built Molecular assemblers - then such machines would be capable (in principle) of reconstructing our bodies atom by atom as they break or otherwise wear out. But that's definitely a stretch - lots of issues of whether such machines would self destruct before they could do any useful work - that kind of thing. SteveBaker 23:21, 23 April 2007 (UTC)

well what i was thinking is that maybe stemcell research can help us live longer. if ur heart starts to fail get a new one with stemcell. since its made from you your body should not reject it. the same with all other parts of your body. i also heard stemcell might be the awnser for other desiese (got i was never able to spell that word) like alzhimers or even the nervous system. for the skin there is that botox thing hehUser:Maverick423 If It Looks Good Nuke It 02:27, 24 April 2007 (UTC)

Even if we could survive every possible 'accident' and cure all diseases, there is still a major problem with living for a long time :( All human DNA contains telomeres at the end of each cromosome, which have no effect on people's genes, but every time the DNA is replicated, a small part of the telomere is lost, so that eventually there is none left and the cell can not divide any more :( So the only way of living in a human body for a very long time would be to find a way to either add more telomeres or replicate DNA without losing a bit each time :( HS7 12:57, 24 April 2007 (UTC)

Yep - that's why Dolly the sheep died prematurely. She was cloned from a six year old sheep - so at her birth, she already had six years too few telemeres - so at her death (at age 6) her cells had used up the 12 years worth of telomeres and could no longer reproduce - in effect, whilst she was only six, her cells were those of a 12 year old sheep. Telomeres are natures defense against cancers - if a cell starts dividing at an unnaturally fast rate, it consumes telomeres at a higher rate and finally can no longer subdivide. Whether we can fix this problem is far from clear - some cancers can make more telomeres - so there is definitely hope. But what's interesting is that cloning ourselves into new bodies won't help. 14:41, 24 April 2007 (UTC)

So where do new telomeres in children come from, as they have the same DNA as their parents?

And does this mean there is always one cell in every animal with the full lenght of telomeres?

woah if this is the case why cant scientist make more of these telomeres? i mean science has come to the point where it can recreate certain compounds why not telomeres? and seeing as how our cells feed off the food we eat, the best application would probably be in a food would it not? User:Maverick423 If It Looks Good Nuke It 19:22, 24 April 2007 (UTC)

The main difficulty with this is geting the DNA sequence inside the cell, inside the nucleus and then attatching it to the ends of every chromosome:( Food only gets into cells once it has been broken down and either disolved in water or passed through protein channels, which can only move small chemicals, with a telomere probably not counting as small:( But they are arranging ways of putting DNA on bits of metal and fireing it into cells :) And they can only do this with one cell at a time, not the hundreds of millions people would need fixing if this was to be viable :( HS7 20:28, 24 April 2007 (UTC)

Identification of a Duck Species

Duck

Does anyone recognise the species of the duck in the picture? I saw it in the Netherlands (outside the parliament buildings) and thought it was very pretty. The only ducks I have ever seen are Mallards, and these were significantly larger.

Many Thanks, Caffm8 18:33, 23 April 2007 (UTC)

It's not a duck but a goose, specifically the Egyptian Goose. Laïka 18:43, 23 April 2007 (UTC)

Thank you. I wonder what they were doing in Den Haag. The article says it's both a duck, a goose and a swan :) Don't really understand that. Caffm8 18:57, 23 April 2007 (UTC)

You're welcome; I only know this because I asked the exact same question last June, although your photo is lot better than mine which helps. Laïka 19:15, 23 April 2007 (UTC)

The article actually says it's a member of the duck, goose and swan family, i.e. a bigger group that contains ducks, geese and swans which are subsets. I guess from the name it should fall into the goose catergory.137.138.46.155 11:51, 24 April 2007 (UTC)

Aparently, it's actually a Shelduck; that is, halfway between a duck and a goose. Laïka 12:09, 24 April 2007 (UTC)

Cervidae "total numbers"

I am interested in the total numbers (not exact, but in relation to each other) of the various main members of the Cervidae (deer) family. I am specifically interested in reindeer (caribou). Are they the most numerous species? -- Fyslee/talk 20:17, 23 April 2007 (UTC)

Lutein

What is its role in reproduction? How/where is it produced in response to Luteinizing Hormone? I couldn't find anything on the wiki except for a description of its properties as a pigment. Thanks! Horia 23:36, 23 April 2007 (UTC)

Are you by chance asking about the corpus luteum? --David Iberri (talk) 23:43, 23 April 2007 (UTC)

I was wondering more about the actual Lutein molecule. The OED defines luteinization as "The formation of lutein in the cells that remain of the Graafian follicle after expulsion of the ovum, during which process the follicle is converted into the corpus luteum; the formation of a corpus luteum". Lutein is defined as "A substance of a deep yellow colour found in the yolk of eggs and the ovaries of animals." Unfortunately I'm having a hard time finding anything on the actual role of lutein. Any ideas? Horia 23:57, 23 April 2007 (UTC)

Couldn't find anything on PubMed or UpToDate relevant to lutein's role in reproduction. Most articles that I found focus on the (as far as I know unsubstantiated) claim that lutein delays age-related macular degeneration. --David Iberri (talk) 23:52, 24 April 2007 (UTC)