- by: NEIL TUROK
- From: The Australian
- March 09, 2013
Thursday, March 21, 2013
Here Are Two Very Interesting And Worthwhile Articles To Provoke Some Deeper Thoughts.
First we have:
DIGITAL information is the crudest, bluntest, most brutal form of information that we know. Everything can be reduced to finite strings of 0s and 1s. It is completely unambiguous and is easily remembered. It reduces everything to black and white, yes or no, and it can be copied easily with complete accuracy. Obviously, analog information is infinitely richer. One analog number can take an infinite number of values, infinitely more values than can be taken by any finite number of digital bits.
The transition from analog to digital sound - from records and tapes to CDs and MP3s - caused a controversy, which continues to this day, about whether a digital reproduction is less rich and interesting to listen to than an analog version. By using more and more digital bits, one can mimic an analog sound to any desired accuracy. Analog sound is inherently more subtle and less jarring than digital. Certainly, even in this digital age, analog instruments show no signs of going out of fashion.
Life's DNA code is digital. Its messages are written in three-letter "words" formed from a four-letter alphabet. Every word codes for an amino acid, and each sentence codes for a protein, made up of a long string of amino acids. The proteins form the basic machinery of life, part of which is dedicated to reading and transcribing DNA into yet more proteins.
Although it is indeed amazing that all of the extravagant diversity and beauty of life is encoded in this way, it is also important to realise that the DNA code itself is not in any way alive.
Although the genetic basis for life is digital, living beings are analog creatures. We are made of plasmas, tissues, membranes, controlled by chemical reactions that depend continuously on concentrations of enzymes and reactants. Our DNA comes to life only when placed in an environment with the right molecules, fluids and sources of energy and nutrients. None of these factors can be described as digital. New DNA sequences arise only as the result of mutations and reshufflings, which are partly environmental and partly quantum mechanical in origin. Two of the key processes that drive evolution - variation and selection - are therefore not digital. The main feature of the digital component of life - DNA - is its persistent, unambiguous character; it can be reproduced and translated into RNA and protein accurately and efficiently. The human body contains tens of trillions of cells, each with an identical copy of the DNA. Every time a cell divides, its DNA is copied.
It is tempting to see the digital DNA code as the fundamental basis of life and our living bodies as merely its servants, with our only function being to preserve our DNA and to enable its reproduction. But it seems to me that one can equally well argue that life, being fundamentally analog, uses digital memory simply to preserve the accuracy of its reproduction. That is, life is a happy combination of mainly digital memory and mainly analog operations.
At first sight, our nerves and brains may appear to be digital, since they fire or do not in response to stimuli, just as the basic digital storage element is 0 or 1. However, the nerve-firing rate can be varied continuously, and nerves can fire in synchrony or in various patterns of disarray. The concentrations and flows of biomolecules involved in key steps, such as the passage of signals across synapses, are analog quantities. In general, our brains appear to be much more nuanced and complex systems than digital processors.
A lot more is found here:
Second we have:
IBM's Watson—the same machine that beat Ken Jennings at Jeopardy—is now churning through case histories at Memorial Sloan-Kettering, learning to make diagnoses and treatment recommendations. This is one in a series of developments suggesting that technology may be about to disrupt health care in the same way it has disrupted so many other industries. Are doctors necessary? Just how far might the automation of medicine go?
Harley lukov didn’t need a miracle. He just needed the right diagnosis. Lukov, a 62-year-old from central New Jersey, had stopped smoking 10 years earlier—fulfilling a promise he’d made to his daughter, after she gave birth to his first grandchild. But decades of cigarettes had taken their toll. Lukov had adenocarcinoma, a common cancer of the lung, and it had spread to his liver. The oncologist ordered a biopsy, testing a surgically removed sample of the tumor to search for particular “driver” mutations. A driver mutation is a specific genetic defect that causes cells to reproduce uncontrollably, interfering with bodily functions and devouring organs. Think of an on/off switch stuck in the “on” direction. With lung cancer, doctors typically test for mutations called EGFR and ALK, in part because those two respond well to specially targeted treatments. But the tests are a long shot: although EGFR and ALK are the two driver mutations doctors typically see with lung cancer, even they are relatively uncommon. When Lukov’s cancer tested negative for both, the oncologist prepared to start a standard chemotherapy regimen—even though it meant the side effects would be worse and the prospects of success slimmer than might be expected using a targeted agent.
But Lukov’s true medical condition wasn’t quite so grim. The tumor did have a driver—a third mutation few oncologists test for in this type of case. It’s called KRAS. Researchers have known about KRAS for a long time, but only recently have they realized that it can be the driver mutation in metastatic lung cancer—and that, in those cases, it responds to the same drugs that turn it off in other tumors. A doctor familiar with both Lukov’s specific medical history and the very latest research might know to make the connection—to add one more biomarker test, for KRAS, and then to find a clinical trial testing the efficacy of KRAS treatments on lung cancer. But the national treatment guidelines for lung cancer don’t recommend such action, and few physicians, however conscientious, would think to do these things.
Did Lukov ultimately get the right treatment? Did his oncologist make the connection between KRAS and his condition, and order the test? He might have, if Lukov were a real patient and the oncologist were a real doctor. They’re not. They are fictional composites developed by researchers at the Memorial Sloan-Kettering Cancer Center in New York, in order to help train—and demonstrate the skills of—IBM’s Watson supercomputer. Yes, this is the same Watson that famously went on Jeopardy and beat two previous human champions. But IBM didn’t build Watson to win game shows. The company is developing Watson to help professionals with complex decision making, like the kind that occurs in oncologists’ offices—and to point out clinical nuances that health professionals might miss on their own.
Information technology that helps doctors and patients make decisions has been around for a long time. Crude online tools like WebMD get millions of visitors a day. But Watson is a different beast. According to IBM, it can digest information and make recommendations much more quickly, and more intelligently, than perhaps any machine before it—processing up to 60 million pages of text per second, even when that text is in the form of plain old prose, or what scientists call “natural language.”
A great deal more is here:
I don’t have much to add rather than to suggest both will reward a careful read and both point to some directions that might turn out to be quite important!
Posted by Dr David G More MB PhD at Thursday, March 21, 2013