Slashdot is powered by your submissions, so send in your scoop


Forgot your password?

Comment: Re:People with artificial lenses can already see U (Score 5, Interesting) 137

by jc42 (#49462895) Attached to: UW Scientists, Biotech Firm May Have Cure For Colorblindness

Turns out the biological lens of your eye blocks UV light, but if you get an artificial lens, your retinas can register UV light.

There's some natural variation....

This has been understood for some time. As others have mentioned, various military orgs have used teams with varied color vision as a way of "seeing through" camouflage. Biologists have suggested that the variety in human color vision is adaptive, giving our hunting ancestors' teams an improved chance of spotting spotting prey against various backgrounds, and the addition of dogs (with their very different color vision from ours) improved this teamwork. This is all hypothetical, though, since (as far as I know) it hasn't actually been tested scientifically.

Back in high school (in the 60s), I had a science teacher who did a good illustration of it all. He made the usual demo of a spectrum using a prism, on a sheet of white paper. Then he had students come up and mark the visible ends of the spectrum, covering up each student's marks with another sheet of paper before the next student made their marks. The result was two columns of dots that didn't line up at all; their variants was around 10% of the width of the spectrum. I'd made marks that I could identify, and saw that my UV mark was right at the average point, while my IR mark was one of the farthest out. This explained some things I'd already noticed about the ways that different people saw colors.

This has been known to the photography industry since color film was first produced. Different varieties of film (and now CCDs) have different sensitivities, and different photographers have different preferences for brands of film based on this.

One of my funny personal anecdotes on the topic was once (in Jr High, as I recall), I asked some visitors why the front-left panel of their car was a different color than the rest of the car. They gave me a funny look, then said the car was all black, which everyone else present agreed with. I objected that only that one panel was black; the rest of the car was a deep red. This got me more funny looks, and the fellow who owned the car said that the car had been in a minor accident that damaged the front-left panel, so it was replaced. After that, my family thought I had something called "black-red color blindness" (which is odd, because I was actually the only one without that defect ;-). I was taken to an optometrist, who verified the "condition", but assured my parents that it wasn't a significant problem, and didn't need treating. Actually, there was a simple treatment: glasses that block near-IR light, and I've accidentally got several sunglasses that do just that, making for oddly muted reds.

As I got more into photography, I eventually noticed that my eyes have slightly different color vision, with things looking slightly bluer in the left eye and slightly redder in the right eye. This seems to be extremely common, actually, though most people don't notice it until it's mentioned and they start trying to spot it in different lighting condition. (Hint: It's often easier to spot in lower-light conditions, and difficult in full sunlight.)

Comment: Re:News for herpetologists (Score 2) 45

by jc42 (#49308301) Attached to: Meet the Carolina Butcher, a 9-Foot Crocodile That Walked On Two Legs

Stuff that matters to nobody else.

Oh, I dunno; a number of fiction writers are probably going to use it as a model for some characters, and then having fun pointing out that they're a realistic interpretation of something that has in fact lived on Earth. A conventional alternate-universe plot would put their intelligent descendants in contact with us weird primates, who never developed on their world because their ancestors ate all the primates.

Comment: Re:Boxen? WTF? (Score 2) 296

by jc42 (#49295795) Attached to: To Avoid NSA Interception, Cisco Will Ship To Decoy Addresses

We might as well start with Lewis Carrol

Or with this well-known one about the absurdities of English spelling:

A plan for the improvement of spelling in the English language
By Mark Twain

For example, in Year 1 that useless letter "c" would be dropped to be replased either by "k" or "s", and likewise "x" would no longer be part of the alphabet. The only kase in which "c" would be retained would be the "ch" formation, which will be dealt with later. Year 2 might reform "w" spelling, so that "which" and "one" would take the same konsonant, wile Year 3 might well abolish "y" replasing it with "i" and iear 4 might fiks the "g/j" anomali wonse and for all.

Generally, then, the improvement would kontinue iear bai iear with iear 5 doing awai with useless double konsonants, and iears 6-12 or so modifaiing vowlz and the rimeiniing voist and unvoist konsonants. Bai iear 15 or sou, it wud fainali bi posibl tu meik ius ov thi ridandant letez "c", "y" and "x"— bai now jast a memori in the maindz ov ould doderez —tu riplais "ch", "sh", and "th" rispektivili.

Fainali, xen, aafte sam 20 iers ov orxogrefkl riform, wi wud hev a lojikl, kohirnt speling in ius xrewawt xe Ingliy-spiking werld.

Comment: Re:Depends on Know-how (Score 1) 385

by jc42 (#49295677) Attached to: Ask Slashdot: Choosing a Laptop To Support Physics Research?

.. As a postdoc and starting faculty member I used to have a Dell and it was blazingly fast ...

Yeah; I once worked in a lab that had a bunch of those. The blazes did a lot of damage to the lab. Myself, I'd prefer a machine that runs cool, especially one that's in my hand or lap, or is left running unattended on a shelf. Sometimes those marketing slogans backfire ... ;-)

Comment: Re:Depends on Know-how (Score 1) 385

by jc42 (#49295517) Attached to: Ask Slashdot: Choosing a Laptop To Support Physics Research?

Ultimately it depends on the user. Those with less knowledge of how to configure linux or with less time to do it should probably look at a mac. However if you have the time and know-how Linux on a Dell will be cheaper and possibly faster performance-wise.

Well, I've been using both linux and Mac for 15 years or so, and I'd found that Macs are often even more frustrating than linux (or other unixoid systems). Thus, when my earlier Macbook Pro was dying, I got a new one with the fancy new "Retina" display. It supposedly had twice the resolution (4x the pixels) as my older Macbook, but it was configured to mimic a tiny screen (or one with giant pixels ;-). It took me several months of googling, tweaking, swearing, etc. to stumble across useful info for reconfiguring it so I can now get 6 usable Terminal windows on the screen, though with slightly fewer rows and columns than the old one gave. I'm sure it can do better, but I've become resigned to the idea that this is probably the best it can do with its marvelous hi-res display. Much of the frustration, of course, is that questions on Mac forums tend to get oh-so-friendly answers that might be summarized as "Don't worry your pretty little head about it; It Just Works." You do get a bit of this from the linux crowd, but there are also folks who like to show off their knowledge to noobs, so if you act like a noob, they give you useful information, and further details if you don't understand something.

The main frustration with linux systems is that it has been difficult to get them with hi-res displays. I've read a number of explanations of why this is. My pocket "smart phone" has as many pixels as the big screen on my home linux box; we should be able to get laptops with about the same resolution and thus many more pixels. OTOH, the linux laptops I've used have come out of the box with the software using the the screen's full resolution, so if you have good eyes, you don't waste time hunting down instructions on how to turn off the "accessibility" stuff.

YMMV, of course; different people have different kinds of knowledge and interests. Marketing aside, there never has been any such thing as a "general purpose computer".

Comment: Re:Boxen? WTF? (Score 2) 296

by jc42 (#49293385) Attached to: To Avoid NSA Interception, Cisco Will Ship To Decoy Addresses

In what fucking language. Pretty sure boxes is the pl. of box. But you know with everyone out there making up new spellings left and right how am I supposed to keep up. (I mean really "rediculous"???? why that one pisses me off so much I'll never know)

Hand in your card and get the fuck out.

Yeah; methinks we're seeing the symptoms of a serious humo[u]r deficiency here. These things have a long history in the English-speaking world. Many of us are quite aware of the ridiculocities that can easily be found in the English language, and a lot of humo[u]rists have gotten audiences laughing by mocking some of the stupider things in our language. This especially applies to the irregular plurals, which of course are derived from plural forms that were once regular (and still are in German), but which became relics a millennium or so back when our ancestors settled on just the -[e]s as the plural marker, but stubbornly insisted on keeping a few hundred of the old plurals around to confuse children and foreigners.

Maybe we should collect a list of links to some of the humorous things that have been written on the topic, and refer people to the list when they post complaints like we've been seeing here. Anyone wanna take on the task?

Comment: Re:Can you please give us a fucking break?? (Score 2) 416

by jc42 (#49277277) Attached to: Politics Is Poisoning NASA's Ability To Do Science

If he really believed climate change was not real, he would want to INCREASE NASA's budget, to find out the truth.

... When money goes to NASA I expect them to use it for space research, not climate research. If I wanted more climate research to be done NASA would not be on my list of organizations to push money towards.

A number of people have voiced that idea here an elsewhere, but it's a bit of an odd argument. Saying that climate research should only be done on Earth is a case of basing all your science on a single case study. But if we really want to understand climate, we should be studying all the atmospheres that are available to us, not just this one planet's atmosphere. And historically, NASA has been a major launcher of space probes, especially those aimed at other planets.

We even have an excellent near-twin of our planet close at hand: Venus is very nearly the same size at Earth, but has a climate that would be instantly fatal to nearly every living thing on Earth. Now, obviously Venus's temperature is partly due to being closer to the sun, but simple physical calculations show that the equilibrium temperatures of Venus and Earth should be much more similar than they are. So most of the different has to be for reasons other than solar input and radiative loss. We understand some of this, but not everything, and somehow I don't think we'll fully understand Venus's climate by restricting our climate research to just our own planet.

It's also interesting that Mars has a climate that is more similar to Earth's than Venus's, though it has the additional difference of lower gravity, resulting in much less atmosphere. Again, NASA has been directly involved in nearly everything we've learned about the Martian climate until fairly recently.

Anyway, I for one would encourage NASA to continue to be involved in climate studies, not just here on Earth, but on all the available worlds that have climates. Basing our behavior on a "sample of one" isn't a very intelligent approach. If we really want to understand how climates work, we should be collecting data from all of the available atmospheres. We really don't want our climate to shift in the direction of Venus or Mars, after all, and the best way to prevent that is to learn why they're the way they are and why ours is different. Historically, NASA has been a major player in what we have learned about the subject.

Comment: Re:A Language With No Rules... (Score 1) 667

by jc42 (#49268359) Attached to: Why There Is No Such Thing as 'Proper English' no Language.

On the contrary; the lack of (legally enforceable) rules is one of the major reasons that English has become the world's main language for most technical uses.

Some years back, I read a good explanation of this by a French researcher, who explained why he published all his papers in English rather than French, and why his group in France used English as their "working" language. His explanation was that, in French, l'Académie Française is the government body in Paris that has the power to set and enforce the standards for the French language. The problem is that in his specialty, as in any technical specialty, it's important that the specialty develop a body of precise technical terms that is clearly understood by the others in the specialty. The major way of doing this is normally to take terms in the general language, and restrict their meaning in the technical jargon. Secondarily, words may be borrowed from other language, or new terms just made up. However, in French the Académie has the legal power to override them, declare their papers to be nonstandard French, block their publication, etc. This potentially makes it difficult for the specialists to develop a precise, unambiguous terminology that they all understand. Government bureaucrats who don't understand the specialty have veto power of their technical terminology.

The English language, however, has no such legal body in any country. This gives English-using researchers, theoreticians, engineers, etc. to discuss issues amongst themselves, and develop their technical jargon as their subject requires. New discoveries can lead to changes in terminology without the permission of the bureaucrats. So, for effective communication among specialists in a technical field, English gives them the freedom to develop jargon that fits their needs, and revise their terminology as the need arises.

If English (most likely of the American variety ;-) were to establish an enforceable set of rules, it would end this technical usefulness, and would eventually push for a shift to a different language without such restrictions.

The followups to this explanation included a number of comments from people with lots of other native language, who all basically agreed with the writer, and said that their field did the same thing.

(OTOH, I had a math prof in college who learned Rumanian, because about half the people in his specialty were in Romania, and published their preliminary papers locally in their native language. They published their main papers in English, but he wanted to follow their local discussions. He already read French and Italian, so it wasn't difficult to pick up a new "degenerate Latin" language. There are a number of other subject areas that have similar situations. Others here can probably comment on other fields with a similar mix of English and one or more local languages.)

Open Source

Linux Kernel Adopts 'Code of Conflict' 93

Posted by Soulskill
from the be-excellent-to-each-other dept.
Motor was one of several readers to note that a small patch recently added to the Linux kernel contains guidelines for discourse and dispute resolution within the community. It's called the "Code of Conflict." Quoting: Your code and ideas behind it will be carefully reviewed, often resulting in critique and criticism. The review will almost always require improvements to the code before it can be included in the kernel. Know that this happens because everyone involved wants to see the best possible solution for the overall success of Linux. .... If however, anyone feels personally abused, threatened, or otherwise uncomfortable due to this process, that is not acceptable. ... As a reviewer of code, please strive to keep things civil and focused on the technical issues involved.

Comment: Re:thrown out in 3...2... (Score 1) 103

by jc42 (#49224581) Attached to: Wikimedia Foundation Files Suit Against NSA and DOJ

The good news here is that the aclu and eff are participating. These orgs are very savvy and wouldn't waste time on a suit with no chance.

The bad news is that, even if the court allows the case to proceed, and they win, the NSA will simply ignore the court's decision and continue their work. They're above (or beside or in a parallel universe to) the legal system.

The only real way to fight them is to find ways to expose their activities to the rest of the world. There are some technical problems with doing this effectively, such as jailing or assassination of outside investigators.

(Is there a documented, verifiable case of any "secret" government organization being limited by the courts, in the US or any other country? Yes, I've read claims that it has happened. But note that term "verifiable". Someone writing an article claiming that it has happened isn't exactly verification. ;-)

Comment: Re:Hilarious (Score 1) 366

What's your point? Do you think that there are people who are immune to rising sea level? Gills maybe? Eh?

Actually, there's at least one known population of humans that expect to benefit from rising sea level: the people of Scandinavia. That part of the world is still bobbing up from the loss of the ice sheets 18,000 years ago. Historically, the shorelines have been falling by about a meter per century. This causes ongoing problems, mostly due to ports turning into dry land. A few years back, I was in Finland and visited a historic site called Mustasaari ("black island"). It's not an island at all; it's about 10 km from the water. In 1600, it was an active port, and around 1350 it probably was an island. By 1700, the town was abandoned, reverting to forest and farmland, and the newer town of Vaasa somewhat to the west had taken over as the local port. Sometimes the ports can migrate downslope, but often the shoreline change doesn't allow that, and the town just dies, as the people move to some other area that's friendlier to their boats. Every port town in the area has always had to face the fact that all their investments in port facitlities, buildings, roads, etc. will become worthless in a few generations.

So one source of humor in that area is based on how good "global warming" sounds. They'll not just be warmer, but their towns will stay put for longer, and you can pass your land and buildings on to your children. So far, the effect has been small, but supposedly measurable. The sea level will probably be nearly stable this century, though geologists predict that in another millenium or two, the Gulf of Bothnia and the Baltic Sea will be reduced to a set of smaller lake connected to the sea by a river.

Along most other shorelines, the story is rather different, of course.

(I've also read reports on the new species arriving on the Antarctic Peninsula. ;-)

Comment: Re:Hilarious (Score 1) 366

"Wait! You're both right!" ;-)

Part of the problem is that "race" is used in both colloquial English and in technical speech with rather different definitions. It is used technically as an informal synonym of "subspecies", and is similar in meaning to "breeding population"; the rough meaning is a group that has small but significant (for recognition, habitat choice, etc.) genetic differences from other populations.

In general, colloquial English, it generally just means any recognizable group, often but not always with superficial but visible differences in appearance. But sometimes it's even less meaningful that that. In the US, one of the commonly-recognized "races" is "Hispanic", which of course is based on language and culture, and can refer to a person of any subspecies who speaks with a Spanish-sounding accent. This is a good illustration of how meaningless the term is in its general usage.

There has been a general effort by biologists to avoid the use of the term, and it's not really officially part of standard terminology. But "subspecies" isn't understood by the general population, and "race" is one syllable rather than three, so the informal usage continues, especially when talking to the general public.

In the case of medical discussions of problems with a genetic component, it's common to use "population" instead, but that has four syllables. ;-) It's mostly useful if the population can be given a name. Thus, Tay-Sachs disease seems to be from a mutation that appeared first in a small eastern-European Jewish population, which of course isn't a "race", but is a recognizable and namable sub-sub-population. Knowing this is medically useful in diagnosis, since it gives a good hint at which tests might be useful when the appropriate symptoms are seen.

Sickle-cell disease is an interesting case, because its population is semi-genetic: It developed in malaria-plagued areas of central Africa, and partly defends against that disease. The population isn't actually a subspecies, since it includes people who are genetically quite different from each other. But the mutation(s) involved spread from group to group because it gives some immunity to malaria (at the cost of many early deaths from sickle-cell disease). Again, knowing about patients' central-African ancestry is medically useful in diagnosis, since it hints at what tests to try first when the symptoms are seen. In the US, the term "African-American" is a racial classification that correlates well with this disease, so it's medically useful despite being biologically somewhat bogus.

The poison-ivy/oak/sumac/etc. problem is actually a lot more complicated, and much of the information about it is of poor scientific/medical quality. Interested readers might try googling for info about the Asian lacquer tree to find some of the most useful information. There is a wide variety of sensitivity to this toxin, and different human populations differ statistically in their reaction to it. There are sensitive and resistant people in all populations, and there are populations that are mostly at one or the other end of the spectrum. It's often medically classified as a "white" problem, but this is an extreme over-simplification. East Asians are often very resistant to it, but they generally know to give lacquered things a number of good washings before using them in ways that involve close physical contact, such as in tableware. Asian artists who work with this lacquer understand its toxicity fairly well, and know how to deal with it. But it's not a simple story, and there's a lot of mythology involved.

Comment: Re:Hilarious (Score 4, Insightful) 366

We ban so many things these days. Try discussing the idea that racial differences go beyond the cosmetic and see how long you last at your job.

That might depend partly on your job. In medical circles, it's fairly well understood that some medical conditions affect certain groups of people more than others. If a doctor were to ignore, say, symptoms of sickle-cell disease in black people on the ground that it's "racist", that could easily be grounds for a malpractice charge, since most of its victims have central-African ancestors. Haemophilia primarily affects people with European royalty in their ancestry. Tay-Sachs disease mostly affects people with a Jewish backtround. And so on. If a medical corporation were to prevent their employees from discussing diseases that have a genetic component, we should hope that the employees publicise the problem and get it overturned.

Of course, a lot of medical organizations do have a religious component, and it wouldn't be too surprising to find that management wants such things classified as "God's will". But if fact that would be terrible medical practice, and should be brought out in the open if it's happening.

In the opposite direction, when young I was one of the few kids in my environment who seemed to be immune to poison ivy, a common problem weed in North America. Eventually I learned the reason: Sensitivity to its toxin is primarily a "white person" problem, because Europe is the only part of the world with no native plants that contain the toxin. Although I look totally European, I'm partly Ojibwa, and I apparently inherited the resistance from my father's father's mother. I'm not complaining, of course, but I would be a little bothered if this "racial" sensitivity were a forbidden topic of discussion in medical circles. I've had friends with very serious reactions to the toxin, and suppressing information about the racial nature of the sensitivity wouldn't have any public health benefits. (And knowing that some people are permanently immune to it is helpful if you'd like to eradicate the plant in an area frequented by white people. ;-)

There are similar problems with decorative plants like poison sumac and Brazilian pepper, which contain the same toxin, and are widely grown as decorative shrubs or trees in South America and Japan, where most people are immune to the toxin. Again, mentioning the racial differences in sensitivity can aid in diagnosing and preventing problems; it can also be useful information if you're looking for people to remove the plants from an area. Florida has a serious problem with an infestation of Brazilian pepper, and (white) people trying to remove - or worse, burn - the plants have had major medical problems as a result. Floridians would be especially dumb to prevent discussion of the genetic component to this sensitivity.

Any given program will expand to fill available memory.