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Laser Incidents With Aircraft On the Rise

Rand310 Re:Laser Filters? (546 comments)

I recall something about this with respect to pilots who might at some point encounter a nuclear blast. Part of the training included wearing an eye patch such that in the event of a nuclear detonation the pilot would not be completely blinded.

more than 3 years ago
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Scientists Create Programmable Bacteria

Rand310 Re:possible original source (117 comments)

The orthogonal refers to the fact that the molecule is not naturally part of the E. coli sensing system - and so the synthetic 'message' is not convoluted or otherwise disturbed by the natural processes already taking place in the E. coli. So yes, this would allow individual cells or populations to pass different bits. You cold have as many bits of information as you found 'orthogonal' signaling molecules.

more than 3 years ago
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Scientists Create Programmable Bacteria

Rand310 Re:Antibiotics? (117 comments)

And even if you wanted to "program" this feature, you'd have to deal with the nasty problem of protein folding in silico. Better to leave this entire process highly parallel in wetware.

there is no need to deal with protein folding in silico - we know a LOT about proteins and how they work just from standard biochemical assays. There are literally tens of thousands of characterized molecules with known DNA sequences from which we can pick and choose useful sets - slightly modify if need be - and then recombine in novel ways inside a cell. And we can do it directly - without having to rely on some kind of directed evolution - which is quite slow. It is very hard to program a specific well-defined program into a phage - whereas the molecular biology to add features, protein sequences and other regulatory DNA to E. coli is trivial at this point. This is not about making a better immune system, it is about making one (or something else) that is entirely characterized and programmed - not one that must undergo thousands of generations of (difficult to control for) selection in order to become useful.

...not to calculate anything fancy.

Again, because we can program any arbitrary code into the bugs, it is trivial to make a bacteria that lights up green when it detects particular chemicals. Or that only grow when you have a fever, or that do other similar calculations. There are of course extreme difficulties when you're talking about therapeutics because you're interacting with the human body. But outside the human body it is only a matter of time before you start seeing bacterial sensors on everything. They are cheap, they are robust, and they can enzymatically recognize certain properties that mechanical sensors may have great difficulty doing, or doing rapidly, or cheaply. And when you can link the sensors with a programmable logic, THEN you get the really cool stuff. This research demonstrates the first steps into getting the programmable logic up and running.

more than 3 years ago
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Scientists Create Programmable Bacteria

Rand310 Re:Antibiotics? (117 comments)

They're inserting synthetic genetic code (with known function) into E. coli that will allow individual bugs to respond in predictable ways to other bugs' chemical signals. So, for example, there is a known DNA sequence that encodes a protein that 'recognizes' signal. There is another sequence that encodes a second signal recognition protein. There is a third sequence that encodes a scaffolding that binds the two signal proteins (an AND gate), and it produces some chemical or enzymatic output. This output is often a small molecule other bacteria can then subsequently recognize.

Once you have enough parts (that are found all over biology, and are slowly being annotated and dissected) you can start to create real computers.

This is very much about passing information between individuals. The 'logic' gates are very much still analogue - in that they are leaky and really only useful at a statistical level, but they are working. But small molecules can act as the medium of transmission between two different individual E. coli in a way that very much resembles a computation.

more than 3 years ago
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Scientists Question Safety of New Airport Scanners

Rand310 The Scientist's Letter of Concern (357 comments)

LETTER OF CONCERN
We are writing to call your attention to serious concerns about the potential health risks of the recently adopted whole body backscatter X-ray airport security scanners. This is an urgent situation as these X-ray scanners are rapidly being implemented as a primary screening step for all air travel passengers.
Our overriding concern is the extent to which the safety of this scanning device has been adequately demonstrated. This can only be determined by a meeting of an impartial panel of experts that would include medical physicists and radiation biologists at which all of the available relevant data is reviewed.
An important consideration is that a large fraction of the population will be subject to the new X-ray scanners and be at potential risk, as discussed below. This raises a number of ‘red flags’. Can we have an urgent second independent evaluation?

The Red Flags
The physics of these X-rays is very telling: the X-rays are Compton-Scattering off outer molecule bonding electrons and thus inelastic (likely breaking bonds). Unlike other scanners, these new devices operate at relatively low beam energies (28keV). The majority of their energy is delivered to the skin and the underlying tissue. Thus, while the dose would be safe if it were distributed throughout the volume of the entire body, the dose to the skin may be dangerously high.
The X-ray dose from these devices has often been compared in the media to the cosmic ray exposure inherent to airplane travel or that of a chest X-ray. However, this comparison is very misleading: both the air travel cosmic ray exposure and chest X- rays have much higher X-ray energies and the health consequences are appropriately understood in terms of the whole body volume dose. In contrast, these new airport scanners are largely depositing their energy into the skin and immediately adjacent tissue, and since this is such a small fraction of body weight/vol, possibly by one to two orders of magnitude, the real dose to the skin is now high.
In addition, it appears that real independent safety data do not exist. A search, ultimately finding top FDA radiation physics staff, suggests that the relevant radiation quantity, the Flux [photons per unit area and time (because this is a scanning device)] has not been characterized. Instead an indirect test (Air Kerma) was made that emphasized the whole body exposure value, and thus it appears that the danger is low when compared to cosmic rays during airplane travel and a chest X-ray dose.
In summary, if the key data (flux-integrated photons per unit values) were available, it would be straightforward to accurately model the dose being deposited in the skin and adjacent tissues using available computer codes, which would resolve the potential concerns over radiation damage.

Our colleagues at UCSF, dermatologists and cancer experts, raise specific important concerns:
A) The large population of older travelers, >65 years of age, is particularly at risk from the mutagenic effects of the X-rays based on the known biology of melanocyte aging.
B) A fraction of the female population is especially sensitive to mutagenesis- provoking radiation leading to breast cancer. Notably, because these women, who have defects in DNA repair mechanisms, are particularly prone to cancer, X-ray mammograms are not performed on them. The dose to breast tissue beneath the skin represents a similar risk.
C) Blood (white blood cells) perfusing the skin is also at risk.
D) The population of immunocompromised individuals--HIV and cancer patients (see above) is likely to be at risk for cancer induction by the high skin dose.
E) The risk of radiation emission to children and adolescents does not appear to have been fully evaluated.
F) The policy towards pregnant women needs to be defined once the theoretical risks to the fetus are determined.
G) Because of the proximity of the testicles to skin, this tissue is at risk for sperm mutagenesis.
H) Have the effects of the radiation on the cornea and thymus been determined?

Moreover, there are a number of ‘red flags’ related to the hardware itself. Because this device can scan a human in a few seconds, the X-ray beam is very intense. Any glitch in power at any point in the hardware (or more importantly in software) that stops the device could cause an intense radiation dose to a single spot on the skin. Who will oversee problems with overall dose after repair or software problems? The TSA is already complaining about resolution limitations; who will keep the manufacturers and/or TSA from just raising the dose, an easy way to improve signal-to-noise and get higher resolution? Lastly, given the recent incident (on December 25th), how do we know whether the manufacturer or TSA, seeking higher resolution, will scan the groin area more slowly leading to a much higher total dose?
After review of the available data we have already obtained, we suggest that additional critical information be obtained, with the goal to minimize the potential health risks of total body scanning. One can study the relevant X-ray dose effects with modern molecular tools. Once a small team of appropriate experts is assembled, an experimental plan can be designed and implemented with the objective of obtaining information relevant to our concerns expressed above, with attention paid to completing the information gathering and formulating recommendations in a timely fashion.

We would like to put our current concerns into perspective. As longstanding UCSF scientists and physicians, we have witnessed critical errors in decisions that have seriously affected the health of thousands of people in the United States. These unfortunate errors were made because of the failure to recognize potential adverse outcomes of decisions made at the federal level. Crises create a sense of urgency that frequently leads to hasty decisions where unintended consequences are not recognized. Examples include the failure of the CDC to recognize the risk of blood transfusions in the early stages of the AIDS epidemic, approval of drugs and devices by the FDA without sufficient review, and improper standards set by the EPA, to name a few. Similarly, there has not been sufficient review of the intermediate and long-term effects of radiation exposure associated with airport scanners. There is good reason to believe that these scanners will increase the risk of cancer to children and other vulnerable populations. We are unanimous in believing that the potential health consequences need to be rigorously studied before these scanners are adopted. Modifications that reduce radiation exposure need to be explored as soon as possible.

In summary we urge you to empower an impartial panel of experts to reevaluate the potential health issues we have raised before there are irrevocable long-term consequences to the health of our country. These negative effects may on balance far outweigh the potential benefit of increased detection of terrorists.

more than 4 years ago
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Scientists Question Safety of New Airport Scanners

Rand310 Re:And yet... (357 comments)

From the letter written by the scientists, not the article written by journalists:

"Unlike other scanners, these new devices operate at relatively low beam energies (28keV). The majority of their energy is delivered to the skin and the underlying tissue. Thus, while the dose would be safe if it were distributed throughout the volume of the entire body, the dose to the skin may be dangerously high.

The X-ray dose from these devices has often been compared in the media to the cosmic ray exposure inherent to airplane travel or that of a chest X-ray. However, this comparison is very misleading: both the air travel cosmic ray exposure and chest X- rays have much higher X-ray energies and the health consequences are appropriately understood in terms of the whole body volume dose. In contrast, these new airport scanners are largely depositing their energy into the skin and immediately adjacent tissue, and since this is such a small fraction of body weight/vol, possibly by one to two orders of magnitude, the real dose to the skin is now high."

more than 4 years ago
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Scientists Question Safety of New Airport Scanners

Rand310 Re:If the dose was calculated right, not a problem (357 comments)

If each individual cell received 0.02, this would be accurate. But some cells in your body are receiving a dosage of almost 0, and others of two orders of magnitude more. Such that a given cell near your skin might have an extremely high dose, while internal organs get nothing. There are a lot of sensitive sites near the surface of a human's skin. Their misuse of units is shoddy at best, and deliberately misleading at worst.

more than 4 years ago
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Scientists Question Safety of New Airport Scanners

Rand310 Re:Nobody cares (357 comments)

Read the letter sent by the scientists. This is true overall, but not true locally. It is true that the total dose your body sees is less than what it sees from cosmic rays (if you average each cell in your body with the total amount of radiation). But it is NOT true at all locally. Your skin cells (and anything near the skin, like white blood cells, breast tissue, testicles, cornea, etc.) all receive VERY high local doses. These do not permeate into the body well, so the average is measured as 'safe' even though for cells on the surface of your body is extraordinarily high.

more than 4 years ago
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Scientists Question Safety of New Airport Scanners

Rand310 Re:Sterilization....the easy way! (357 comments)

Apparently this is true for your 'body' as most of the radiation doesn't get much past the skin. But for the skin it can be "1 to 2 orders of magnitude" greater than background cosmic radiation even at altitude according the scientists.

So yeah, your heart sees no more radiation than the trip into the air. But your neck, your eyes, your breasts if you have them, and your testicles if you have them all receive a great deal of local radiation - far more than would be considered safe for a routine examination. But the way the safety is 'calculated' by the people who designed the machine it looks okay on paper.

more than 4 years ago
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Facebook Throws Privacy Advocates a Bone

Rand310 Even MORE information for them! (126 comments)

When you white-list your computer, the suggestions are something like "my home computer", and "office computer 1", and "vacation computer". This simply provides facebook with even more personal information to use in targeted advertising. If anything, though this does enhance security, it is at the expense of even more of the user's privacy.

more than 4 years ago
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Memorizing Language / Spelling Techniques?

Rand310 Re:Flashcards (237 comments)

yep. Anki. It's the way to go.

more than 4 years ago
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"Immortal Molecule" Evolves — How Close To Synthetic Life?

Rand310 Re:what is a living molecule? (270 comments)

I just saw this professor speak in a lecture to his peers. His conclusion was that what is preventing his molecules from being 'alive' is their inability to undertake novel action. They only go so far as to maximize their sustainability environment and nothing more. Though the 'environments' he gave the molecules were in fact static. It is only a matter of time before we can test situations which really do test our definitions.

more than 4 years ago
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Tesla Motors To Suspend Roadster Production

Rand310 Re:Uh oh (401 comments)

Also be careful how you think about cost - this is a true and completely electric car. It will have a completely different cost curve. FAR fewer moving parts. Many fewer consumables. And no gasoline or oil. A 50k electric (if all the bugs and R&D is done (which is exactly what we're 'paying' Tesla to do)) could cost substantially less than a 30k gasoline car over its lifetime. It's still hard to tell. But it is different.

more than 4 years ago
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Tesla Motors To Suspend Roadster Production

Rand310 Re:More Publicly Financed Toys for the Wealthy (401 comments)

It is a different situation when going backwards in performance in order to get ahead in the long run. There is a steep energy barrier (that only gets steeper in a truly capitalist market) that needs to be lowered through government funded catalysis. Going from horses to cars was simply a matter of investment. It was inevitable. Going from oil to electric will eventually become inevitable, but we can speed it and aid it to ease the transition.

more than 4 years ago
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Tesla Motors To Suspend Roadster Production

Rand310 Re:More Publicly Financed Toys for the Wealthy (401 comments)

Their target market IS the average person. But they realize that with the current state of technology that they can't get there. So they start with the premium stuff. Put their best foot forward, and do all the R&D with heavy numbers and package it in a snazzy roadster. Get some cashflow on the ridiculously expensive tech, and then as economies of scale kick in, use that tech to make cheaper and cheaper cars. They are not 80s-Honda-cheap, but neither are they intending to remain a Lotus/Ferrari style market.

more than 4 years ago
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Iceland's Data Center Push Finally Gets Traction

Rand310 WikiLeaks & Iceland's Legislation (117 comments)

Wikileaks has a proposal to get a bunch of different free-speech, safe-harbor, journalist-protection style legislation through Iceland so as to both spur this kind of development, as well as provide a political safe-haven for data. Apparently it has caught on pretty well locally, and with a small population it's not particularly difficult to get such legislation passed on short notice.

http://www.wikileaks.org/

more than 4 years ago
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Google Hacked, May Pull Out of China

Rand310 Re:Free trade of ideas, anyone? (687 comments)

The internet has an interesting barrier on entry though - a computer and an internet connection. If you can afford those things in China, you can afford what is being advertised to you. The 'average' wages tell you little about the distribution of wealth in China. There are a number of very well off people living in the large cities. Luxury cars have a 100% luxury tax, and yet you still see countless Ferraris, BMWs & Mercedes. And even if the proportion of the population that is wealthy enough to be a customer of Google is much smaller than in the US or elsewhere, you get to multiply it by their enormous population. I don't have the numbers, but I would wager that by number there are a great deal more (USD) millionaires in China than there are in particular smaller European states, and Google seems to do well in those places.

more than 4 years ago
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Google Hacked, May Pull Out of China

Rand310 Re:Is it? (687 comments)

Youtube is already inaccessible in China and has been for at least 3 years.

Google as a search engine is not particularly interesting to the ordinary citizen in China.

I don't know enough about google's presence in China from their corporate perspective, but from the perspective of someone who lived in China and who works with many Chinese, much more importantly than their google.com, are their backend tools, their technical abilities, their industrial and commercial applications. And I think that is where the strife is taking place, not with the public at large.

While I lived over there I introduced a lot of my friends to gmail and gchat. They provided a means out of the Chinese ecosystem through which they could communicate with friends/others around the world. They liked those tools. I think google's decision may in fact affect mostly those people who are in the know, and have less affect on those who tow the common line.

more than 4 years ago
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Microsoft's Risky Tablet Announcement

Rand310 Re:If MS thinks they're attcking Apple.... (338 comments)

I guarantee that there will be a 'Apple vs MS vs etc' column that will be posted shortly after each device's debut. Not only do MS and Apple want to be on that list, but a whole host of other companies are releasing products right now just so that they too can be on that list. It would be quite possible to suck up a decent amount of free market space by riding off of Apple's announcement. Apple released this device with these features at this price point, while CompanyA released a similar device with these features at this price point. CompanyA automatically gets free news, a shot at a market and possibly even sales all while riding Apple's momentum.

more than 4 years ago

Submissions

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Twitter's privacy policy and the Wikileaks case

Rand310 Rand310 writes  |  more than 2 years ago

Rand310 (264407) writes "The federal judge in the Wikileaks case cited in his order a version of Twitter's privacy policy from 2010, rather than the very different policy that existed when Appelbaum, Gonggrijp and Jonsdottir created their Twitter accounts back in 2008. That older policy actually promised users that Twitter would keep their data private unless they violated the company's terms of service.

If the judge were to examine the privacy policy that existed when these three targets signed up for a Twitter account, he might decide that they do in fact have a reasonable expectation of privacy and that the government needs a warrant to get the data."

Link to Original Source
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Comment on DRM for the FTC's DRM Workshop

Rand310 Rand310 writes  |  more than 5 years ago

Rand310 (264407) writes "The FTC is soliciting comments today (Feb 13th) in regards to DRM for their upcoming digital rights management conference in late March in Seattle. Ars is running a story about how many of the current comments, come from gamers harried by issues and limitations imposed on paying customers. The story also suggest 'the big players in these sorts of public hearings follow a predictable plan: they hold their filings until the final day for submissions, apparently out of a desire not to tip their hand to opponents and give them a chance to directly address their arguments.'

Submit your comments; let them be heard."

Link to Original Source
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2008 Abel Prize - Thompson & Tits

Rand310 Rand310 writes  |  more than 6 years ago

Rand310 (264407) writes ""For their profound achievements in algebra and in particular for shaping modern group theory" John Griggs Thompson and Jacques Tits are awarded the Abel Prize for their contributions to what is known as group theory. Group theory is the "science of symmetries", where one tries to understand the relation between reflections and rotations of a icosahedron, to reveal the secrets of Rubik's cube or to control the symmetries among the solutions of the fifth degree equation, as done by Niels Henrik Abel. Thompson and Tits have invented important new concepts and proved fundamental results in this field, and their names now appear prominently in the history of group theory. Thompson revolutionized the theory of finite groups by proving extraordinarily deep theorems that laid the foundation for the complete classification of finite simple groups. Tits created a new and highly influential vision of groups as geometric objects.

A description of the winner's work."

Link to Original Source

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