It should take on the order of seconds to calculate. You probably need to uncomment the little endian define. The checksum is simply the sum of a range of bytes in the file. For small changes, it is quite feasible to update it manually. Just calculate the difference in byte values that you've changed and update the 4 byte checksum (little-endian) located at 0x421c. Thus, if you change an 'A' to a 'B', just increment the existing checksum at 0x421c by one.
It's possible to change the text, menus, etc. also. Now you can change the "Do not disconnect." text along with the graphic. Warning: this is nowhere near as user friendly as the ipodwizard program, but it worked for me using a 4th gen. iPod on linux. Just download the firmware with dd from the/dev/sdx1 partition, open up a hex editor and replace whatever text you want. There's a checksum located at 0x421C that needs to be updated. There's a checksum2.c program that can calculate and write a firmware's checksum. I'm not going to post a link to it due to the author's wish to avoid a slashdotting but a bit of searching should find it. I found that this program didn't calculate the checksum correctly but always returned a value 16418 too high so I just modified it to subtract this constant. This is almost certainly specific for my particular ipod verson. After the firmware is written back with dd, the text modifications show up. All the text that can be reasonably edited is located together in one block in the file. I changed what shows up under Settings->About->Format from "Windows" to "Linux" so now I have a Linux iPod.
Yes, without the EC, everyone would be equal. Everyone would have no power whatsoever. Politicians would only have to appeal to the majority. Being in the minority (even a 49% minority) means you would be powerless under a popular vote. At least now, politicians have to appeal to at least enough minority voters in certain states to be elected. Overall, the voter base as a whole benefits with the EC. Yes it could be re-divided better and it is unlikely to ever occur, but it still seems better what we have.
Here's another way to look at it. Suppose candidate A is supported 60% to 40% over candidate B. If a popular vote were held, you could argue that absolutely no one's votes matter. There would be little incentive for either candidate to campaign. It would be the same situation as in Massachusetts right now but on a national scale. With the EC, it is conceivable that candidate B could win and this makes it necessary for both candidiates to campaign for votes.
I was for eliminating the electoral college until I read this: Math Against Tyranny. It also makes the analogy to baseball runs vs. games. Alan Natapoff has mathematically shown that voters have more power with the current system where power is defined as the ability to tip an election in any one direction. Basically, if it was purely a popular vote, the only way your vote would matter is if the rest of the voters split exactly down the middle. Given the size of the US population, the probability of this is extremely low. Especially given that people tend to lean towards one candidate or the other, the chance of deadlock is essentially nil under a popular vote. That means each voter has no power to tip an election and thus politicians have no reason to listen to them. Dividing into smaller groups means that each group is more likely to deadlock and so each voter has more power. Thus, what happened in Florida in 2000 was a good thing. In fact, the best thing to do is to re-divide up the nation into groups such that every single group would be very likely to deadlock. The winner would then take-all from each group, making it so that all politicians would have to work to win votes in every single group.
having heard part of that panel at the Synthetic Biology 1.0 conference, the article is a bit misleading in the respect of licensing. Church suggested the licensing of the technology, such as DNA synthesis. The design of systems shouldn't be licensed. Anyone can and should be encouraged to design systems, but if it requires a license to actually build the system, then it becomes easier to control what gets released. Currently any lab could in theory synthesize oligos but few actually do it themselves. If we require licensing for DNA synthesis technologies and make unlicensed oligo synthesizers illegal, then personal oligo synthesizers will no longer be sold on ebay.
The original post of 45 nt/s is correct for transcription and translation (the speed of RNA polymerase and ribosomes). 1000 nt/s is for replication (the speed of DNA polymerase).
Cancer has been around in the human population also. One would imagine that we would have evolved to be resistant also like these mice if it was easy and stable to do so. It may not be "Oh, cancer is good" but rather, "Defending against cancer is bad." Who knows if these mice are normal otherwise? Maybe for every cancer cell that gets killed, a brain cell goes along with it.
Read the actual
article
if you have access. It's quite interesting and much more coherent than my description below.
They actually implement a 2-state finite state automata with a two letter alphabet. The approach is basically something like the following. The 'hardware' is a restriction enzyme that is an offset cutter. The 'software' are pieces of DNA with 4-base DNA overhangs.
The transition table is essentially coded in the software DNA
molecules. The current state of the machine and the current input
symbol is coded for by a unique 4 base overhang. The software DNA has
4 base overhang to match a particular state, symbol. The software DNA binds to the
input DNA, and then the restriction enzyme, since it is a 9-base offset
cutter to the right, cuts the input to be in a new state. Something like
the following:
Software FFFFF??OOOO fffff??
Input nnnnn--- NNNNN---SSSS
F: FokI site O: overhang -: spacers S: current state N: next state ?: number of ? determines next state
Changing the number of ? spacers in the software changes where in
the input you cut and therefore chooses between two of the possible set of four base overhangs for the next state. All the energy for the computation comes from breaking up the input DNA.
Based on their model, the maximum number of states possible in the
FSA appears to be dependent on the size of the offset for FokI and
I think it's like 5 states. (Possible to have more states with
larger offset cutter?) The maximum number of automata state and input symbol combinations, since they use
a 4 base overhang appears to be 4^4. So it's not quite general
enough to match any regular expression, and not even close to a
read/write tape for a Turing machine, but is an interesting approach.
Slashdot Mirror
It should take on the order of seconds to calculate. You probably need to uncomment the little endian define. The checksum is simply the sum of a range of bytes in the file. For small changes, it is quite feasible to update it manually. Just calculate the difference in byte values that you've changed and update the 4 byte checksum (little-endian) located at 0x421c. Thus, if you change an 'A' to a 'B', just increment the existing checksum at 0x421c by one.
It's possible to change the text, menus, etc. also. Now you can change the "Do not disconnect." text along with the graphic. Warning: this is nowhere near as user friendly as the ipodwizard program, but it worked for me using a 4th gen. iPod on linux. Just download the firmware with dd from the /dev/sdx1 partition, open up a hex editor and replace whatever text you want. There's a checksum located at 0x421C that needs to be updated. There's a checksum2.c program that can calculate and write a firmware's checksum. I'm not going to post a link to it due to the author's wish to avoid a slashdotting but a bit of searching should find it. I found that this program didn't calculate the checksum correctly but always returned a value 16418 too high so I just modified it to subtract this constant. This is almost certainly specific for my particular ipod verson. After the firmware is written back with dd, the text modifications show up. All the text that can be reasonably edited is located together in one block in the file. I changed what shows up under Settings->About->Format from "Windows" to "Linux" so now I have a Linux iPod.
Here's another way to look at it. Suppose candidate A is supported 60% to 40% over candidate B. If a popular vote were held, you could argue that absolutely no one's votes matter. There would be little incentive for either candidate to campaign. It would be the same situation as in Massachusetts right now but on a national scale. With the EC, it is conceivable that candidate B could win and this makes it necessary for both candidiates to campaign for votes.
I was for eliminating the electoral college until I read this: Math Against Tyranny. It also makes the analogy to baseball runs vs. games. Alan Natapoff has mathematically shown that voters have more power with the current system where power is defined as the ability to tip an election in any one direction. Basically, if it was purely a popular vote, the only way your vote would matter is if the rest of the voters split exactly down the middle. Given the size of the US population, the probability of this is extremely low. Especially given that people tend to lean towards one candidate or the other, the chance of deadlock is essentially nil under a popular vote. That means each voter has no power to tip an election and thus politicians have no reason to listen to them. Dividing into smaller groups means that each group is more likely to deadlock and so each voter has more power. Thus, what happened in Florida in 2000 was a good thing. In fact, the best thing to do is to re-divide up the nation into groups such that every single group would be very likely to deadlock. The winner would then take-all from each group, making it so that all politicians would have to work to win votes in every single group.
go to ebay and search for DNA synthesizer. Anyone can buy one for less than the price of many computers.
having heard part of that panel at the Synthetic Biology 1.0 conference, the article is a bit misleading in the respect of licensing. Church suggested the licensing of the technology, such as DNA synthesis. The design of systems shouldn't be licensed. Anyone can and should be encouraged to design systems, but if it requires a license to actually build the system, then it becomes easier to control what gets released. Currently any lab could in theory synthesize oligos but few actually do it themselves. If we require licensing for DNA synthesis technologies and make unlicensed oligo synthesizers illegal, then personal oligo synthesizers will no longer be sold on ebay.
The original post of 45 nt/s is correct for transcription and translation (the speed of RNA polymerase and ribosomes). 1000 nt/s is for replication (the speed of DNA polymerase).
Cancer has been around in the human population also. One would imagine that we would have evolved to be resistant also like these mice if it was easy and stable to do so. It may not be "Oh, cancer is good" but rather, "Defending against cancer is bad." Who knows if these mice are normal otherwise? Maybe for every cancer cell that gets killed, a brain cell goes along with it.
They actually implement a 2-state finite state automata with a two letter alphabet. The approach is basically something like the following. The 'hardware' is a restriction enzyme that is an offset cutter. The 'software' are pieces of DNA with 4-base DNA overhangs.
The transition table is essentially coded in the software DNA molecules. The current state of the machine and the current input symbol is coded for by a unique 4 base overhang. The software DNA has 4 base overhang to match a particular state, symbol. The software DNA binds to the input DNA, and then the restriction enzyme, since it is a 9-base offset cutter to the right, cuts the input to be in a new state. Something like the following:
Changing the number of ? spacers in the software changes where in the input you cut and therefore chooses between two of the possible set of four base overhangs for the next state. All the energy for the computation comes from breaking up the input DNA.
Based on their model, the maximum number of states possible in the FSA appears to be dependent on the size of the offset for FokI and I think it's like 5 states. (Possible to have more states with larger offset cutter?) The maximum number of automata state and input symbol combinations, since they use a 4 base overhang appears to be 4^4. So it's not quite general enough to match any regular expression, and not even close to a read/write tape for a Turing machine, but is an interesting approach.