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Two South African Cancer Patients Receive 3D Printed Titanium Jaw Implants

pz Re:Don't Call it Waste (69 comments)

At the prices medical-grade titanium goes for, it is most certainly not wasted. The machined Ti is reclaimed (or at least it would be if I were in charge). Stating that there is 80% waste is marketing hyperbole. A fairer comparison would count the unsintered powder in the 3D build machine, and would end up being unfavorable to the 3D process.

But if you're in the business of making replacement body parts, you might well be starting with a generic titanium casting (or one of a series of different sizes) and machining it down to fit. Artificial hip joints are sometimes made that way.

Don't get me wrong, 3D printing makes a lot of sense for highly-custom items... although one needs to worry about the potential infection and reaction issues given the inherent porosity of sintered material that give purchase for pathogens, and lots of surface area for irritants that will slowly leech out.

2 days ago

A Warm-Feeling Wooden Keyboard (Video)

pz Buy a Kinesis instead (79 comments)

1. "All the Keyboards" didn't apparently include a Kinesis. At least there isn't one visible amongst the few photos linked.

2. The new keyboard looks an awful lot like a Kinesis.

3. I stopped watching the video after the first 10 seconds because it was too awful.

4. The web site shows a keyboard with what appears to be a metal case, and the text references aluminum, as does the blog. Wood isn't part of the equation here. Maybe in the early prototypes, but not in the production models, apparently.

5. Any decent keyboard driver (and there are lots of aftermarket add-ons) support macro definitions. Nice that this new keyboard supports it, but certainly not a defining characteristic.

6. Just go buy a Kinesis. It's been in production for a long time, and they work great.

3 days ago

Favorite "Go!" Phrase?

pz Who? (701 comments)


about a week ago

Comcast Customer Service Rep Just Won't Take No For an Answer

pz Re:Same business model, different business (401 comments)

"The little yellow rabbits with the red eyes told me to cancel. There are so many of them here now."
"I need to tie up some loose ends before heading over to the Comcast office with my AK-47."
Switch to German. If the CSR speaks German, switch to French. Then Portuguese. Russian. Greek. Etc.
"Oh, that's really interesting, please tell me more [wait for reply] REALLY? That's so interesting. Please tell me more. [wait for reply] I didn't quite understand that, could you repeat it? ..."
"Zorg said it must be done."
"The CIA keeps sneaking into my house through the Internets to read my mind while I sleep."
"What did you say your name was? [type, type, type] OK, then, I've updated your Facebook page for you. Hope you like the new photos -- boy that sex toy sure is big!"
"Oh, can you wait a sec? There's someone at the door." [leave phone on table by loud, badly tuned radio, and walk away for a good 40 minutes]
Go to the bathroom and make appropriate noises as if defecating with some difficulty and repeatedly flushing, but continue to hold the conversation.
Hand the phone to your 5 year old.
Aim an air horn at the microphone.
"Each time I try to move the cable box, the electrons keep spilling out."
"When I use the Internet at my friend's house, it's OK, but at my house, all the photos are upside down."
"I need to spend more special time with my hamster."
"I'm dead."
"I've just had enough of the sparks."
"It interferes with my hair dryer."
"This chick said she'd sleep with me if I cancel my cable."
"The Internet is too big."

about two weeks ago

Ikea Sends IkeaHackers Blog a C&D Order

pz Re:IKEA's name is the big deal (207 comments)

Tax avoidance makes more sense than any other speculation in this discussion.

Were IKEA organized as a normal for-profit venture, then anyone with half a brain at IKEA would see the utility of IkeaHackers and do one of a handful of things:

1. Buy them outright.
2. Obtain favorable advertising terms in exchange for licensing (eg, ikeahackers gets to keep running ads, but 50% of the spots must be filled with IKEA adverts, and sales-active links to the official items mentioned in each article must be included).
3. Think they're cute, and provide gratis branding coaching (including direction on proper use of their logo, precise color usage, etc) in exchange for disclaimers, and big, obvious links back to IKEA.
4. Sign an exclusive advertising deal: gets to keep operating, but must only carry IKEA adverts, with some affiliate payment structure for completed sales that originate on so that the site can continue to live on.
5. Similar mutually-beneficial arrangements . . .

IKEA have an enthusiastic fan base who, inspired by reading the blog, will likely go out to buy more IKEA product. This is not just a good demographic, but a great big juicy one. These are the people they *want* shopping in their stores, the people they *want* to reach through media campaigns.

So why turn them away? The only conditions that come to mind are when bringing the web site into the fold has larger, more threatening implications to the corporate structure, as the parent post suggests.

about a month and a half ago

TechCrunch and Others On the Microsoft Surface Pro 3

pz Re:Might be the perfect tablet for academia (136 comments)

Paper. I have lab notebooks from my undergraduate years (through the present) that I refer to, because it's easy to do so. If I need to find something, and don't recall exactly where it is, a simple flipping of the pages, and I've found it in a matter of seconds.

Call me a luddite, but electronic lab books don't have sufficient usability yet. My post-doc uses one, and he's far less efficient with it (and writes much less as a result) than I am with pen and paper. Importantly, human memory is at least partially (some would argue primarily, and I wouldn't dispute that) visually based, and not having that aspect of where you wrote something on the page, or in what color ink, or with what size handwriting, etc., makes a big difference to usability. The closest I've seen to viable electronic notebooks are the specialized pens that have small internal cameras that require special paper to use. Last I checked, though, they were prohibitively expensive compared to a traditional pen and lab book.

Pen and paper have had thousands of years of development. It's going to take a while longer before the electronic version is usable.

about 2 months ago

Brain Injury Turns Man Into Math Genius

pz Re:Uh... (208 comments)

I don't buy the thermodynamic argument. That's an epiphenomenon (i.e., correlation not causation).

Basic mathematics does not consider time. Nor does it really consider sequential ordering properly until it deals with the notion of state, State begets the field of Computational Theory. Before a proper wrangling of the ideas at the core of Computational Theory (as embodied in Turing Machines, for example), there was a horrific thrashing-about that was particularly inelegant, such as the attempts in First Order Logic to capture the meaning of state.

Now, when you talk about infinity, you are effectively saying that results from Computational Theory are being computed by a machine that takes zero time to get from one state to the next. Nothing in the physical universe takes zero time, and so infinity is considered to be ill-supported by Nature. That's the crux of the Constructionist objections.

Now why should mathematics be beyond time? It describes space pretty well. Why should time be exempt?

about 3 months ago

Brain Injury Turns Man Into Math Genius

pz Re:Uh... (208 comments)

There are a fair handful of constructionists (aka finitists, or number theorists who do not like infinities) who would care to disagree.

Although I'm not a constructionist, I am related to one by birth, and nearly always find something off-putting about mathematical arguments that rely on infinities. Sure, they're fun to play with, but reasoning about them means you're essentially being fast-and-loose with time, and I've not been convinced that's OK.

about 3 months ago

One-a-Day-Compiles: Good Enough For Government Work In 1983

pz Re:no flight involved? (230 comments)

And I bet that because the costs of running a program were so high -- in time and monetary terms -- that your programs were correct, nearly 100% of the time.

We get intellectually lazy when a debug loop is only a few seconds long.

about 3 months ago

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 5 months 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 5 months 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 5 months 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 5 months 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 5 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 5 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 5 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 6 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 6 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 7 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 ( 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 8 months ago


pz hasn't submitted any stories.



pz pz writes  |  more than 11 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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