A big problem with Google is that it can only retrieve web sites that have the exact search term. Type in "automobile manufacturers" and you won't find a single website for an auto maker. That's because those sites don't use the term, even though sites that point to them might.
There's a way out of this, though. Jon Kleinberg of Cornell describes an interesting application of graph theory to the Internet to yield better searches where the search term may not even be present.
Tim's list is good. If you're going to be writing games or plotting data or doing graphics, you also need:
geometry
trig
matrix algebra
Graph theory has some suprising applications to the Internet, as Jon Kleinberg of Cornell has pointed out. I've written an article about how graphs and matrices can be used to wring some interesting information out of a search engine.
Yes, we've entered our decadent phase. I'm surprised no one here has put their finger on a big cause of our slide from scientific dominance: the growing tide of fundamentalism in America. These folks have single-handedly managed to ban funding for embryo and stem cell science, and have a huge impact on the current President.
These guys are determined to take us back to the dark ages, when people spent a lot more time praying and a lot less time asking embarrassing questions.
I can't believe the slashdot crowd is falling for this wacky professor. Here's a quote from a rebuttal I wrote some weeks ago...
"The good doctor would have loved communist Russia, where there was a single brand of state jam, and mercifully few choices. Many people in Russia, however, favored the state vodka as a tonic to mitigate the pain of that bleak, choice-free existence."
I don't think you should look at these cells as a potential human. Unlike human creation, there is no mixing of genes. The egg is never fertilized. All the researchers hope to do is to take a skin cell from a patient, reprogram it so it goes back to an embryonic state, and then use those "rejuvenated" cells to cure the patient's disease. There's an egg involved, but only the cytoplasm is used -- there is no maternal DNA involved. It may even be possible to use an animal egg to reprogram the cell.
Pretty soon, we'll figure out the complicated recipe for egg cytoplasm, and then we won't need an egg anymore. Will that change its moral standing?
The problem is, this technology demonstrates that any cell of your body could give rise to a potential human. So showering would be akin to genocide. But common sense tells us that you ought to be able to do with your cells what you want. Are they potential humans? Yes, every one of them, not just the billions of sperm cells produced daily by a man or the million eggs that a woman is born with. So at some point we have to say that mere human potential is not sufficient to confer personhood.
As for adult stem cells, we should definitely follow up on their fantastic potential. But they won't be able to carry the whole load. Embryonic stem cells are immortal, and adult stem cells seem to share the 50-division limit of other adult cells. That, unfortunately, rules them out for therapies that require genetic engineering.
Dr. Verfaillie herself says that both adult and embryonic stem cell research is important. And Dr. Weissman of Stanford has shown that adult stem cells are not as plastic as was hoped.
The most important distinction between the two types of stem cell is that only embryonic stem cells are immortal. Adult stem cells can't be expanded in culture for very long before they die.
Immortality -- the ability to divide continually in a petri dish -- is essential for genetic engineering. For instance, hemophiliacs are missing a gene that aids clotting. You can build this gene into a plasmid (a circular bit of DNA) along with a gene that confers resistance to a specific antibiotic. A plasmid can only insert itself into a cell that is dividing, when the DNA is spread out and vulnerable to hacking. When the plasmid inserts itself, it rarely goes where you want it to go, so you need to do millions of insertions just to get a few keepers. Then you dose the dish with antibiotics. If the hemophilia gene landed in a good place and is able to express itself, then that cell should also be resistant to antibiotics. The majority of the cells die off, and now you need to pump up the population of the few cells that survived -- the ones with a functioning gene. All that expansion requires a cell line that can divide indefinitely -- and that rules out adult stem cells.
That said, of course we need MORE research, not less. Both adult and embryonic stem cells will likely be useful for therapy. The diseases targeted by stem cell therapies include the biggest killers of all: heart disease, diabetes, Parkinson's, Alzheimers, and many others. This is the most astonishing breakthrough in medical history -- giving us the ability to regenerate any tissue -- and we're walking away from it.
Instead we should be launching a Manhattan Project to generate results, ASAP. To the millions of people suffering from those diseases, the wait is literally killing them.
Actually the problem could become starker than choosing between private or public funding. The Brownback bill before congress would make it a crime to do what Stanford is doing, punishable by 10 years in jail and a million dollar fine for each researcher.
And yet, the US says, in Roe v. Wade, that such embryos are NOT humans, and NOT deserving of any human rights.
The reality is that if you are dying of heart disease, this technique will create stem cells that are genetic clones of your own tissue. No new human is created. Right now, researchers know of only one way to create such stem cells, and that involves using an egg to "reprogram" the patient's own cells.
As far as when to define the beginning of life, every religion has a different take and there is no unanimity. Scientists are hard-put to describe the exact moment when a blastocyst is really a unique person. But to sacrifice a tiny dot of cells -- your OWN DAMN CELLS, for chrissake -- is not tantamount to abortion.
On the other hand, NOT to use these cells when people are suffering is totally immoral. A majority of the world's religions concur: Jews, Moslems, Buddhists and even Presbyterians all support stem-cell research. Only hard-line Catholics and assorted fundamentalists are trying to make this an abortion issue. Stem cell therapy is a life-saver, and we are cowards and idiots if we let religion determine the future direction of medical research.
As Paul Berg (the nobelist who started genetic engineering) points out, you can't clone a human in a petri dish. To make a human you need a woman to carry the baby to term. Cloning humans thus requires a mother, a medical facility and doctors. Not something you could do by stealth.
Therefore it's easy to ban human cloning, and we needn't worry about that darned slippery slope.
In fact, when we pull the plug on someone to harvest organs, the sole criterion is brain death. That's because without a working nervous system, you no longer have "humanness." That doesn't apply to retarded people, who have functioning nervous systems, nor does it apply to people in comas. This stance is approved by every major religion except Shinto.
If brain death is accepted as the end of life, why shouldn't the onset of mental function define the beginning? The stem cells we are talking about come from 5-day old blastocysts. Embryonic stem cells are completely undifferentiated. A blastocyst has no skin, no muscle, no bone and no nervous tissue at all. Although it is human tissue, it is not -- according to US law and common sense -- a human.
The reason researchers are pursuing cloning is because there is no other way to prevent tissue rejection. The stem cells that result are genetically identical to the patient. No new human is created at any point. This is simply a way to expand a few cells to a large population. Only embryonic stem cells are immortal, and that's what you need to culture a large batch.
Really, this is not much different than a skin culture, which also depends on stem cells to magically keep growing. The problem with the hard stance of the anti-stem cell group is that they are trying to stop a medical breakthough that could end the suffering of hundreds of millions of people around the world. It is immoral to withhold a therapy with such promise, especially when no one else is hurt, and the patient's own cells are all that is at stake.
Slashdot Mirror
There's a way out of this, though. Jon Kleinberg of Cornell describes an interesting application of graph theory to the Internet to yield better searches where the search term may not even be present.
I've written an article and a program to demonstrate the technique at Mathematics of the Internet.
- geometry
- trig
- matrix algebra
Graph theory has some suprising applications to the Internet, as Jon Kleinberg of Cornell has pointed out. I've written an article about how graphs and matrices can be used to wring some interesting information out of a search engine.These guys are determined to take us back to the dark ages, when people spent a lot more time praying and a lot less time asking embarrassing questions.
"The good doctor would have loved communist Russia, where there was a single brand of state jam, and mercifully few choices. Many people in Russia, however, favored the state vodka as a tonic to mitigate the pain of that bleak, choice-free existence."
The article is at: Science For People
Pretty soon, we'll figure out the complicated recipe for egg cytoplasm, and then we won't need an egg anymore. Will that change its moral standing?
The problem is, this technology demonstrates that any cell of your body could give rise to a potential human. So showering would be akin to genocide. But common sense tells us that you ought to be able to do with your cells what you want. Are they potential humans? Yes, every one of them, not just the billions of sperm cells produced daily by a man or the million eggs that a woman is born with. So at some point we have to say that mere human potential is not sufficient to confer personhood.
As for adult stem cells, we should definitely follow up on their fantastic potential. But they won't be able to carry the whole load. Embryonic stem cells are immortal, and adult stem cells seem to share the 50-division limit of other adult cells. That, unfortunately, rules them out for therapies that require genetic engineering.
The most important distinction between the two types of stem cell is that only embryonic stem cells are immortal. Adult stem cells can't be expanded in culture for very long before they die.
Immortality -- the ability to divide continually in a petri dish -- is essential for genetic engineering. For instance, hemophiliacs are missing a gene that aids clotting. You can build this gene into a plasmid (a circular bit of DNA) along with a gene that confers resistance to a specific antibiotic. A plasmid can only insert itself into a cell that is dividing, when the DNA is spread out and vulnerable to hacking. When the plasmid inserts itself, it rarely goes where you want it to go, so you need to do millions of insertions just to get a few keepers. Then you dose the dish with antibiotics. If the hemophilia gene landed in a good place and is able to express itself, then that cell should also be resistant to antibiotics. The majority of the cells die off, and now you need to pump up the population of the few cells that survived -- the ones with a functioning gene. All that expansion requires a cell line that can divide indefinitely -- and that rules out adult stem cells.
That said, of course we need MORE research, not less. Both adult and embryonic stem cells will likely be useful for therapy. The diseases targeted by stem cell therapies include the biggest killers of all: heart disease, diabetes, Parkinson's, Alzheimers, and many others. This is the most astonishing breakthrough in medical history -- giving us the ability to regenerate any tissue -- and we're walking away from it.
Instead we should be launching a Manhattan Project to generate results, ASAP. To the millions of people suffering from those diseases, the wait is literally killing them.
Actually the problem could become starker than choosing between private or public funding. The Brownback bill before congress would make it a crime to do what Stanford is doing, punishable by 10 years in jail and a million dollar fine for each researcher.
The reality is that if you are dying of heart disease, this technique will create stem cells that are genetic clones of your own tissue. No new human is created. Right now, researchers know of only one way to create such stem cells, and that involves using an egg to "reprogram" the patient's own cells.
As far as when to define the beginning of life, every religion has a different take and there is no unanimity. Scientists are hard-put to describe the exact moment when a blastocyst is really a unique person. But to sacrifice a tiny dot of cells -- your OWN DAMN CELLS, for chrissake -- is not tantamount to abortion.
On the other hand, NOT to use these cells when people are suffering is totally immoral. A majority of the world's religions concur: Jews, Moslems, Buddhists and even Presbyterians all support stem-cell research. Only hard-line Catholics and assorted fundamentalists are trying to make this an abortion issue. Stem cell therapy is a life-saver, and we are cowards and idiots if we let religion determine the future direction of medical research.
Therefore it's easy to ban human cloning, and we needn't worry about that darned slippery slope.
If brain death is accepted as the end of life, why shouldn't the onset of mental function define the beginning? The stem cells we are talking about come from 5-day old blastocysts. Embryonic stem cells are completely undifferentiated. A blastocyst has no skin, no muscle, no bone and no nervous tissue at all. Although it is human tissue, it is not -- according to US law and common sense -- a human.
The reason researchers are pursuing cloning is because there is no other way to prevent tissue rejection. The stem cells that result are genetically identical to the patient. No new human is created at any point. This is simply a way to expand a few cells to a large population. Only embryonic stem cells are immortal, and that's what you need to culture a large batch.
Really, this is not much different than a skin culture, which also depends on stem cells to magically keep growing. The problem with the hard stance of the anti-stem cell group is that they are trying to stop a medical breakthough that could end the suffering of hundreds of millions of people around the world. It is immoral to withhold a therapy with such promise, especially when no one else is hurt, and the patient's own cells are all that is at stake.