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Stanford Bioengineer Develops a 50-cent Paper Microscope

pz Re:How to get the lenses (83 comments)

Feh. So the news article says he's using industrial grit. The presumably more authoritative arXiv paper states

Ball Lenses.
The ball lenses used in constructing Foldscopes included material types borosilicate, BK7 borosilicate, sapphire, ruby, and S-LAH79. The vendors included Swiss Jewel Co, Edmund Optics, and Winsted Precision Ball. Part numbers for some select lenses include: 300m sapphire lens from Swiss Jewel Co. (Model B0.30S), 200m sapphire lenses from Swiss Jewel Co. (Model B0.20S), 2.4mm borosilicate lenses from Winsted Precision Ball (P/N 3200940F1ZZ00A0), 300m BK7 borosilicate lenses from Swiss Jewel Co. (Model BK7-0.30S), and 1.0mm BK7 borosilicate lenses from Swiss Jewel Co. (Model BK7-1.00). Note that half-ball lenses from both Edmund Optics and Swiss Jewel Co. were also tested for use as condenser lenses for the LEDs.

So they aren't exactly industrial grit, but very tiny lenses that look like they were originally intended for the telecommunications industry. The question of how does one get these lenses is answered by, "pick up the phone and call one of the listed suppliers who specialize in micro-spheres of clear, hard stuff."

about a month ago

Stanford Bioengineer Develops a 50-cent Paper Microscope

pz Re:How to get the lenses (83 comments)

If you read the article (I know, I know) you'll learn that he uses industrial grit, also known as glass beads, which are tiny bits of glass that are reasonably spherical and ridiculously cheap. The quoted lens cost in the article is $0.17, but unless I'm misunderstanding something, like how special the grit is that he's using, or what kind of secondary selection process is required to pick out beads that will make good lenses, that should be closer to 0.17 cents, not 0.17 dollars.

about a month ago

NASA Forgets How To Talk To ICE/ISEE-3 Spacecraft

pz Re:What would NASA say to it? (166 comments)

So because they are no longer new, we should abandon the Mars Rovers, Cassini, the Viking probes, and other projects just because they are beyond their mission lifetime?

We should stop measuring lunar albedo just because it's always the same? We should stop the pitch drop experiment? We shouldn't have measured the cosmic background radiation to look for spatial variations? We shouldn't have measured continental drift because it can't possibly happen and mountains don't move? Just because something appears static (and without comparing against previous measurements, we have no means for verifying that), does not mean it isn't changing over longer time scales that are still very important.

I'll repeat my thesis: we are so data-poor about the solar system that the feed from any single working probe is vital. The cost of receiving data is trivial compared to the cost of construction and launch.

about a month and a half ago

NASA Forgets How To Talk To ICE/ISEE-3 Spacecraft

pz Re:What would NASA say to it? (166 comments)

The cost of launching anything is staggering, and it gets more stupendously staggering with the size of the orbit. Each probe is important. We are nowhere near having so much data about our solar system -- forget the universe as a whole -- that any single operating probe should be considered junk.

about a month and a half ago

Publishers Withdraw More Than 120 Fake Papers

pz Re:science has no defense against hooliganism (62 comments)

Conferences are not journals. The peer-review comes during the presentation, not when the abstract is submitted. If the session moderator doesn't know the submitter, maybe he'll look at the abstract a bit more closely, but he's not going to send the abstract out to three other people in the field to vet it. So it gets published.

Depends on the field. Some conferences are very hard to get into, and there is a rigorous peer-review process (I can think of two of the conferences in my field with acceptance rates at or below 30%). Others accept essentially anything and everything (like those semi-scam conferences in China I keep getting invited to). I'd wager, however, that the majority of meetings are somewhere in the middle, accepting most submissions that sound reasonable, as the organizers trust that the cost of attending and presenting is sufficient disincentive to trolls.

about 2 months ago

Making Sure Our Lab Equipment Isn't Tricking Us

pz Re:again with the assumptions. (108 comments)

You cannot have entanglement without interaction, you cannot have interaction between two things that lie outside of each other's light cones.

My extremely fuzzy understanding from freshman physics is that the universe is thought to have undergone an expansion early on that was, indeed, faster than light. That post-big-bang period was called "inflation", an idea Dr. Alan Guth came up with (and he happened to be my freshman physics lecturer). So it is possible that two systems that became entangled prior to inflation are now outside each other's light cones.

about 2 months ago

Vikings' Secret Code Cracked

pz substitution cipher? (89 comments)

From the description it sounds like a simple substitution cipher (from their examples, /e/ for /f/, and /n/ for /k/). How hard can that be to decode if you have enough of the text? Yes, neato that we can now read certain notes that have been encoded for 900 years, but were they really only undeciphered that long because no one had a proper, scholarly look at them?

about 2 months ago

Sound System Simulates the Roar of a Rocket Launch

pz Re:154dB is not fatal, or unusual (113 comments)

It's one thing to do that inside a car (which is what, 6 x 4 x 9 feet ... or maybe a little larger than that?). It's quite another to do it inside a huge room that's 36 x 30 x 54 feet in size. It's also worth noting that car audio competitions use a single frequency. The LEAP facility is broadband, since it needs to simulate the sound of a launching rocket.

about 2 months ago

'Opportunity' Celebrates 10 Year Anniversary Roving Mars

pz Re:Not Orders Of Magnitude (51 comments)

You need two digits to write the number 90. You need four to write the number that represents ten years of days, 3650 (modulo leap years). Sounds like two orders of magnitude. And it's a good example of why orders of magnitude are so rough an estimation.

about 3 months ago

US Customs Destroys Virtuoso's Flutes Because They Were "Agricultural Items"

pz Re:Tragic, but almost understandable ... (894 comments)

An important sentence was left out of the summary, which explained that customs mistook the instruments for pieces of bamboo. Judging from the photo accompanying the article, the confusion is almost understandable. It looks like a home made instrument that may or may not have been prepared properly given restrictions on agricultural products. (Example: they may not have been concerned about the bamboo per se, but rather invasive insects that may be in it since the reeds may not have been treated.)

I'm not an insect biologist, but I'd be surprised if 10+ year old bamboo has any remaining viable insect life when kept as a musical instrument (rather than, say, being left outdoors). The photo from the linked article does not look like something that was freshly cut.

about 4 months ago

First Images of a Heart Injected With Liquid Metal

pz Say what? (115 comments)

They say gallium is chemically inert, non-toxic to humans and can be injected and sucked out without leaving a residue.

Doing even the most cursory of searches on gallium and reading through the Wikipedia entry (http://en.wikipedia.org/wiki/Gallium) would suggest that gallium is not chemically intert, may not be non-toxic to humans, and given that extremities can easily get cold enough to drop below the freezing point of gallium, I'd have to say that it might rather well leave a residue, forget about the stickiness others have reported.

Yea, that'd be great: inject liquid metal, have it thicken and solidify in your feet and fingertips because you step outside on a brisk day, giving you the equivalent of massive frostbite. No thank you.

There are growing numbers of Chinese researchers in my field (neuroscience) and their results always need to be taken with an extra-large grain of salt. It looks like the same is true here.

about 4 months ago

Artificial Blood Made In Romania

pz VIOLET PINK! (232 comments)

Did anyone read the Wikipedia entry?

"Hemerythrin and myohemerythrin are essentially colorless when deoxygenated, but turn a violet-pink in the oxygenated state."

Since much of our skin tone (for lighter colored skins) comes from blood, this is going to make for some VERY interesting looking people!!!

about 6 months ago

First Experimental Evidence That Time Is an Emergent Quantum Phenomenon

pz Re:Hmm (530 comments)

If time is an emergent phenomenon, then how does the first event happen? If time does not yet exist, then there is no was to distinguish an event. By the parent's suggestion, time can only be propelled forward when already in motion, by the contribution of each new event. The very ideas of "first" and "new" presuppose the existence of time, and thus despite this likely significant scientific work, we continue to have a tautology until an instantiation somehow starts things off.

We are still, also, a long way away from understanding what causes wavefunction collapse, since the notion of observation is clearly ludicrous: there are no observers in the center of the sun, or on the far side of Jupiter, as two minor examples.

about 6 months ago

The Curious Mind of Ada Lovelace

pz Re:Not the first programmer. (110 comments)

Indeed, especially since the skills of programming a mechanical engine go many eons farther back with, I believe, the invention of the loom. The result was somewhat different (a woven pattern, rather than a scalar value), but the idea of a set of sequentially executed instructions with loops, counting variables, and exceptions, started a long time before Babbage. Knitting and crocheting is rather quite similar, and embodies similarily pre-existing art, as well.

about 6 months ago

What's Lost When a Meeting Goes Virtual

pz Re:old habits in new medium (96 comments)

Terminology. Seems like the parent poster and a lot of other respondents are picking apart the use of the word "meeting" when used as a synonym for scientific conference. Frankly, I've never seen anyone do that before with such misdirected certainty. The OP clearly shows that this is a scientific meeting ("NASA's Lunar Science Forum became the largest scientific gathering..."). In my neck of the world, we have 35,000 people scientific meetings that are also called conferences and even congresses. The smaller ones are called symposia or workshops. I organize one that meets every two years (we explicitly emphasize the more informal interaction phase of such gatherings, which our participants appreciate greatly). Everyone understands that, in that context, "meeting" is a synonym for "conference".

So why all the nit-picking from conflating a scientific meeting with a business meeting? These two beasts are different kinds of events with different goals, different structure, and different levels of participation.

about 6 months ago

3mm Inexpensive Chip Revolutionizes Electron Accelerators

pz Re:so we wasted a shit load of money on colliders? (113 comments)

If you read the article, you'll realize that there is a separate laser accelerator necessary BEFORE this chip, and then a second high-power IR laser necessary to drive the chip.

More-or-less, they've increased the efficiency of laser-based electron acceleration. Good on them, but the solution isn't, as the summary suggests by omission, just a small chip alone and nothing else.

More importantly for the parent (I know, I know, don't feed the trolls), the presented accelerator only accelerates electrons, and is intended as a gamma and x-ray source. That's very different from accelerating electrons and positrons to nearly the speed of light, or protons, or atomic nuclei, etc. To do high-energy physics, you need big, big accelerators. The device to accelerate a single subatomic particle to levels where it carries as much energy as a brick dropped on your foot, isn't going to be a crystal a few millimeters on a side.

about 7 months ago

Request to Falsify Data Published In Chemistry Journal

pz Re:The obvious answer is... (163 comments)

I run a scientific research lab in a Big University You Have Heard Of. I had a conversation with an intern and a post-doc earlier this week where we talked about figures that could be added to a review paper the intern is working on. I swear I used the words, "I'll make up a figure ..." to describe the actions of collecting the necessary supporting data to create a figure for the paper that my post-doc suggested would be instructional. "Make up" in this case meant, "construct," and wholly lacked nefarious, subversive, or deceptive connotations.

And I speak English as my mother tongue.

The so-called conspiracy to commit fraud here is a bunch of hooey. The only thing the authors are guilty of is not submitting a fully completed manuscript.

about 8 months ago

Request to Falsify Data Published In Chemistry Journal

pz Re:Science - It Works (163 comments)

Your order-of-magnitude higher ID than the parent poster suggests an explanation.

Myself, I like Courier. But then, I'm in the lower 10x of that equation.

And please, if you're going to criticize someone's choice of font, take a moment to do it with precision and figure out what the name of the font is.

about 8 months ago

Sci-Fi Stories That Predicted the Surveillance State

pz Why exclude 1984? (213 comments)

Given that Orwell got so very much right about the future, why exclude 1984 from the list? Just to make an interesting discussion that would have been largely already well-hashed-out otherwise?

about 9 months ago

Describe Any Location On Earth In 3 Words

pz Re:Continuity (478 comments)

I'm sitting at beach.country.pineapple and my co-worker is at closing.rheumatoid.begin.

Yeah, they should have implemented a more continuous system such that if, for example, two addresses had no words in common, they'd be quite distant, one word, within a large region, two words, a small region. Then, on top of that, put in alphabetic sorting so that elephant.reciprocity.meander is pretty close to elephant.reciprocity.nominate and really close to elephant.recapitulate.meander.

Double plus good if they had made the three words subject-verb-object sentences (but maybe there aren't enough English words for that).

While the current approach is an unfortunate miss from the human usability aspect, at least they managed to put short descriptors in urban areas, leaving longer ones for the middle of big bodies of water.

about 9 months ago


pz hasn't submitted any stories.



pz pz writes  |  more than 10 years ago

The Blackjacks were a small (okay, perhaps not-so-small) band in Boston from the heyday of local music in Boston. Their biggest hit Saturday, which made a splash on the college airwaves, starts with the lyrics in my signature.

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