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3-D Printed "Iron Man" Prosthetic Hands Now Available For Kids

Sarten-X Re:biocompatibility (64 comments)

No, but in a previous job I did assist clinical researchers doing this kind of testing. The examples I gave are pretty easy questions to test for. The hard one is usually "Does this product increase the risk of cancer?"

4 hours ago

3-D Printed "Iron Man" Prosthetic Hands Now Available For Kids

Sarten-X Re:biocompatibility (64 comments)

This guy comes up with something cool and you are shilling for the medical-gov't industrial complex.

Hardly. This guy comes up with something cool, and I'm wary of the claim that it will somehow overthrow the existing system, mostly because to informed observers, the current system isn't actually unreasonable (mostly, anyway). There are good reasons behind all of the seemingly-insane details, but they're not as obvious as "some kid is missing a hand".

In fact, I actually have to give quite a bit of credit to the designer of this particular device. On his website, he's not encouraging kids to try the thing or making any claims that it's something particularly special. Rather, he's asking for help from experts to refine the design and turn it into something that is fully-tested and documented. If he can do that and still keep it printable (by end users or even trained technicians... either would be a help), then we'll have a real boon to the state of the art.

I wish him the best of luck, but I also recognize that the obstacles he faces are a bit more realistic (and i daresay more difficult) than fighting a conspiracy theory.

6 hours ago

3-D Printed "Iron Man" Prosthetic Hands Now Available For Kids

Sarten-X Re:biocompatibility (64 comments)

I can tell you nobody has ever thought it was all that important with gloves and watchbands and we don't have a small army of people who were nerve damaged by their casio.

And I can tell you that nerve damage (especially around the fingertips) is important to glove manufacturers, especially concerning sporting gloves, where the risk of such damage is high with or without gloves.

As for watchbands, I actually do know a few people who've had allergic reactions to watchbands of various kinds, starting with myself. I can't wear a gold watch, because after a few hours my wrist turns red, and after an evening of wearing it my lower arm is covered in small red bumps. I have a lesser reaction to my gold wedding ring, but I've never bothered finding out exactly which part of the alloy it is that I'm allergic to. In discussions with others, I've met folks allergic to plastic and cloth watchbands as well as metals, some of whose allergies didn't show up until after months of use.

I can tell you that if it costs $40,000 and you don't have that kind of cash laying around, it might as well not exist at all.

That's what insurance is for. Sure, it's a slim chance that I'll ever need a $40,000 medical device, but that's why I pay into the pool. If I ever do need it and don't have the cash lying around, my insurance provider does. If I never do need it, then my premiums went mostly to somebody else in the pool who did.

Are you claiming people are better off with nothing? Are you willing to say that to their faces? Sorry, you're not rich enough to have a hand?

No, I'm saying that the cheapest options present more risks that have not been mitigated. I have no problem informing people of the risks they face, and I sincerely hope that a doctor would inform his patients of the risk associated with any treatment, regardless of the cost.

Or consider canes. If a cane is used improperly, it can cause back shoulder and arm pain. Should we make canes cost $40,000 or should we just adjust them differently if things start hurting?

For a cane, it's a different matter. Canes typically do not have prolonged contact with the wearer and their well-studied risks do not often cause long-term problems once the adjustments have been made.

Imagine the disaster it would be for the economy if we all had to wear only medically approved clothes complete with $40,000 belts and $100,000 shoes. But OMG, what if the belt fails and their pants fall and cause them to trip and trigger a nuclear meltdown, millions of lives are at stake here! $100,000 is such a small price to pay in order to safely not go naked in public!

...and what is the actual risk of that slippery slope? Certainly it's nowhere near probable enough that we'd need to regulate clothing as tightly as medical devices. If you're working with high-energy devices, however, the risk posed by clothing is far greater. I don't recall exactly which jurisdiction requires it, but I know that every piece of clothing worn at my local nuclear plant must be cotton. Cotton burns, while synthetic fibers usually melt. Though often cheaper, synthetic clothes increase the damage from accidents enough to warrant that small amount of regulation.

I imagine the kid will do what the rest of us do. If the hand starts causing pain he'll use it less until it can be adjusted.

By that time, the damage may already be permanent. That's one of the things that research would study before handing it off to an unsuspecting patient.

Meanwhile, unlike before, he has a functional prosthetic hand.

"Functional" prostheses are available for far less than $40,000, and typically are used temporarily while a primary device is being built or repaired.

I'll bet that the $500 beater is infinitely more useful than a Ferrari to someone who will never be able to afford a Ferrari.

....until they're dead because the airbag was stripped for resale and the seat belts were worn out.

In other words, that looks like about $39,955 worth of FUD (and unicorn hair). Most people really can't afford that much FUD. Thankfully, I'm not in the market for a prosthetic hand, but if I was, I would at least try the $45 one first.

In other words, you have no idea what a risk analysis is, but you follow the hacker mentality in thinking that you can do anything if you have the raw material and a tool to work it, without the need for actual expertise. As long as the stated objective is met, that's good enough, right?

Medicine doesn't work that way. Medicine (ideally) isn't about just meeting the primary target, but about improving someone's health. Sometimes, that means doing nothing, and occasionally it even means letting people die rather than making the rest of their life miserable. Throughout the process, every decision is based on risk. Every drug has a risk of side effects, every test has a risk of being erroneous, and even if a doctor performs to the best standards available, there is always a risk that their patient will die.

That's why we have the FDA. That's why we run clinical trials. That's why medicine costs so damned much, because someone has to do the research and find out what the risks are, before asking patients to commit their well-being to a new device.

6 hours ago

3-D Printed "Iron Man" Prosthetic Hands Now Available For Kids

Sarten-X Re:biocompatibility (64 comments)

So can you tell me what the long-term effects of wearing this $45 printed device are?

Is it weighted such that it pulls muscles awkwardly, causing pain after a few months of continuous use? Does the constant contact with skin cause any nerve damage? If worn during physical activity, does it create an additional risk of shattering or otherwise injuring the wearer or others?

Can you show test results indicating otherwise, even when the user may not have it attached properly? What resources are available so the user can be certain they're properly fitting the device?

Approved medical devices are expensive because they meet all applicable regulations, and have documentation to prove it. They've been reviewed and tested by experts in the field, who understand exactly what subtle problems to look for that are likely to cause harmful effects in the future. One of the primary principles of medicine is to do no harm. Can you assure patients that this 3D-printed model will be harmless?

Yes, you can buy a beat-up used car for $500. It will still accomplish the obvious goal of transporting you from point A to point B, but it's not going to be as good in the long run as a more expensive one.


If You're Connected, Apple Collects Your Data

Sarten-X Re:Yay :D (292 comments)

Enabling the video camera or microphone won't actually help. You'd need both to determine if the user was actually using their phone, and the processing cost needed to perform that kind of recognition on a large scale would be so ridiculously expensive that it would undermine any additional benefit from the research.

Statistically, a user waiting 60 seconds before searching is uninteresting. It's an outlier, so the developers really don't care what happened. Far more useful would be an observation that 75% of users use the center enter key to submit queries, 20% use the mouse, and 5% use the enter key on the numeric keypad, combined with an observation that 80% of mouse users move the cursor around after a period of inactivity before clicking. To a design team, that means that the users' attention has shifted to typing, and they've forgotten where the mouse is. Perhaps the mouse should highlight in some way when it first moves...

Similarly, the actual content of searches doesn't matter from a UI perspective. If you're having trouble searching for something, it doesn't matter if you're looking for instructions to knit a sweater for a kitten, or the mixture used in the Oklahoma City bombing. On the other hand, the exact search text is useful to the folks developing the search engine, so they can put the most relevant results at the top of the list. Of course, the search engine team doesn't care about how long it takes the user to find their mouse cursor.

This leads to one of the most entertaining aspects of the whole privacy debate. Gathering data is easy, but proper anonymizing is hard. Practically speaking, the analysis of the gathered data is often easier than ensuring that data is anonymous. For example, there are certain combinations of ZIP code and state that identify as few as 30 people within the continental United States, so any data set that includes both ZIP code and state is probably not sufficiently anonymous. It's far easier to simply collect only what's needed for a particular team, and make sure nothing else can be connected to that record. One database records that somebody searched for "geriatric german grandmas spanking spanish men", and another knows that user submitted a search with a mouse, and perhaps another knows that the user is located in western Iowa. With no way to connect the records, the business need is fulfilled and the user's privacy is effectively safe... but the legal disclosure will still simply say that the company collects all those things, stirring up a nice panic.


Robot SmackDowns Wants To Bring Robot Death Matches To an Arena Near You

Sarten-X Re:Uh, we already went through this (80 comments)

Back when BattleBots was the thing, I considered building one... but you hit on all the major problems, which were only slightly less intractable back then.

To have any chance of making it past preliminary trials, the robot would have to be somewhat successful. That ruled out most of my creative designs. Even making a boring spinner still would have cost a hefty portion of my paycheck, and the required workspace wouldn't have fit comfortably in my apartment. Transporting the thing would have presented more logistics challenges, and even if I'd solved those, the time and hassle to build something just to be torn apart was a pretty steep expense.

Fighting robots is not an everyman's sport. It's a more modern fox hunt.

2 days ago

Debian Talks About Systemd Once Again

Sarten-X Re:Hope! (516 comments)

this goes against much of the traditional Linux spirit of small self-contained bits that can be swapped out at will.

In my mind, this comes down to whether we want a better functioning OS or an OS that adheres to the mindset that I think attracted many of us to Linux in the first place.

Personally, that principle of having many swappable self-contained bits is one of the worst qualities on UNIX.

I've been using GNU/Linux for over a decade. I know my way around most distros, and I can usually figure out what I need to do to accomplish any task... usually. The biggest problem I face now is that distros have so many small components doing their small tasks that figuring out exactly which component is responsible for a given task is no small feat.

I understand and appreciate the programming simplicity that a small component brings, but from a user's (or admin's) perspective, the operating environment is now more cluttered. As distros pick and choose their preferred swappable components, the view gets worse. Sure, I know exactly what the "finger" command does, but it's not obvious that "pinky" is an alternative, because having a lightweight finger command is apparently an important thing. Some distros will even create symlinks or scripts to provide alternative common names for their chosen packages, but there's seldom a guarantee that the input or output will be the same. This is why the first step of many build processes is to examine the environment and figure out exactly what is available on the system, often using methods that uncomfortably remind me of browser-detecting JavaScript.

I'm not saying that systemd is the solution we need, or even that it is a solution. I've just dealt with far too many poorly-named packages to have excessive reverence for this archaic principle.

We should also keep in mind that Linux itself, as a monolithic kernel, defies the concept. By design, the kernel's one job is to interface with every piece of hardware on the machine. Is it really so far out of line to define systemd's one job as interfacing with every service provider in the OS?

3 days ago

PETA Is Not Happy That Google Used a Camel To Get a Desert "StreetView"

Sarten-X Re:PETA won't be happy until all animals are extin (367 comments)

If you actually asked the question of "what does ethical corporate usage of beasts of burden look like?", you'd end up with a very complicated answer.

On the other hand, why should there even be the concept of a "beast of burden"? The real question is "what does ethical interaction with animals look like?", and PETA seems to have taken the position that there is practically no such thing. To the PETA fanatics, any deviation from an animal's natural life is cruel. To an extent, they have a point - where mankind once relied on animals to provide capabilities humans do not possess, technology has now progressed to the point where there is little need for domesticated animals.

Like in so many cases, the madness is perfectly reasonable from a particular perspective.

about a week ago

Internet Explorer Implements HTTP/2 Support

Sarten-X Re:Header Compression + Binary Headers (122 comments)

The theory is that by saving network time receiving the smaller compressed header, the total time is still less.

Of course, this assumes that you're on a slow enough network that the compression savings are worth it. Since typically latency is a bigger problem than throughput, I don't see compression as being terribly important.

Similarly with the binary protocol: Parsing speed isn't the real problem. I'd rather have a plaintext protocol that I can test with PuTTY than save a few cycles parsing.

about two weeks ago

California Governor Vetoes Bill Requiring Warrants For Drone Surveillance

Sarten-X Re:Here's the bill: public notice key (115 comments)

The last word is probably the most damning.

There's a very popular school of thought in security that keeping capabilities secret is a means to reduce risk*. Such a vague requirement to disclose capabilities is open to lawsuits arguing that the disclosure must include things like maximum range, speed, radar size, and so forth, effectively providing an instruction manual for criminals looking to evade such a drone, who now know that their escape plan must include driving so fast for so far.

* No, it's not security through obscurity. Security through obscurity is where the security of the system is compromised by knowledge, whereas keeping the capabilities of a secure system secret only increases the expense (and therefore lowers the chance) of an attack against an otherwise-secure system.

about three weeks ago

Could We Abort a Manned Mission To Mars?

Sarten-X Re:Should we? (267 comments)

The universe is probably littered with the one-planet graves of cultures which made the sensible economic decision that there's no good reason to go into space--each discovered, studied, and remembered by the ones who made the irrational decision.

-Randall Munroe

about three weeks ago

Could We Abort a Manned Mission To Mars?

Sarten-X Re:Should we? (267 comments)

...but we know it's not mapped. We've mapped a good chunk of sea floor, and figured out what to expect. Maybe we could find some new geologic features or something, and those biologists still have a lot of work to do naming everything, but we know more or less what's down there. For an oceanographer, saying "I have no idea what's there" is a sign that you haven't done your research, not that we've hit the limits of our instruments. That's still a valid justification for space exploration, though. We have no idea what other worlds are like, because we haven't sent enough probes and instruments to find out. We simply don't know what's under those clouds, or what that surface is made of, or why that moon is that particular color.

about three weeks ago

Could We Abort a Manned Mission To Mars?

Sarten-X Re:Should we? (267 comments)

I will never understand the quasi-religious fervor some people have about space.

It's not about space. It's about not-Earth.

For most practical purposes, Earth has no more undiscovered continents, no more unexplored territory, and no more absolute wilderness. Sure, there's some areas that are generally undisturbed, but we know just about all there is to know about them. There are no more mysteries lying just beyond the horizon. There is only human civilization. There are cell phones, satellites, and rescue teams standing ready. Human exploration is at a standstill.

There are some places left to go to fill in the gaps in our knowledge. We can cut deeper into the jungles, and dive deeper into the oceans, but we still know what we don't know.

The next horizon for humanity's exploration is space. That's where we'll next spread our human empire, and for those who care about such things, the enthusiasm for space is natural.

about three weeks ago

Could We Abort a Manned Mission To Mars?

Sarten-X Re:No, who cares? (267 comments)

May we all die in novel circumstances.

about three weeks ago

Sierra Nevada Corp. Files Legal Challenge Against NASA Commercial Contracts

Sarten-X Re:Sierra Nevada - - I love their beer! (127 comments)

This is how government contracts work.

Including the lawsuit phase, which is really the only chance the companies have to compete openly. Bids are usually keep secret from the competitors until a contract is awarded, so if they want to directly compete and argue their benefits over another's offer, the loser asks for a review.

This is business as usual.

about three weeks ago

Consumer Reports: New iPhones Not As Bendy As Believed

Sarten-X Re:Useless (304 comments)

Torque is what matters.

If you test bending in the middle, you put 70 pounds force (approximately 300 newtons) in the middle, and support the ends firmly. That means that if the weakest point is in the middle, the torque on that point is (2 x 150 newtons x 80 mm), as the length of the lever arm to the support at the edge is about 80 mm. We'll ignore the fact that the test support is really a little bit inside that, and assume that the subject is supported right at the edge. Note also that the force is 150 newtons, which is half of the 70 pounds force used to break the phone, because the force is opposed evenly by two supports. Their equal force is then summed, which is why our total torque has that "2" scalar, giving us a total of 24 newton-meters of torque.

If we bend off-center, such as half-way towards one of the ends, the forces on the test supports are no longer equal. Our lever arms are now 120 and 40 mm, and the force would be unevenly distributed as well. The force is distributed inversely to the length of the lever arms, so the short arm, being 25% of the length, now supports 75% of the load, which is 225 newtons. The long arm supports 25%, which is 75 newtons. This gives us a total torque of (225 newtons * 40mm + 75 newtons * 120mm), for a total of only 18 newton-meters of torque.

Since testing off-center actually applies less torque to the test subject, the question then becomes one of whether the weak point is really 25% weaker than the rest of the beam.

However, we can also compute the torque on the supposed weak point during the center test. In that case, the lever arms can be computed as though they behave as a typical lever, scaling the force. they apply. The longer lever would be a class 3 lever, which would reduce the effective force of the test to 100 newtons. On the other hand, the shorter arm would behave as a class 2 lever, increasing the force to 300 newtons. The total torque on the weak point during a center test, then, is (100 newtons * 120mm + 300 newtons * 40mm), which is again 24 newton-meters.

If the weak point were really weaker than anywhere else in the phone, it would break during the center-loaded test. Looking at the pictures from Consumer Reports, though, that's exactly what happened. On both the iPhone 6 and iPhone 6 Plus, the most significant damage is at the edge of the volume buttons closest to the center.

However, it's worth noting that the Consumer Reports test was conducted until the screen detached, even if that happened after the phone itself was permanently deformed. Looking at other pictures of bent phones, their screens have not separated from the cases, so they likely used less force to deform. Bending to separation, though, provides a consistent point of comparison to other phones, which may have internal damage even if their cases return to normal.

Disclaimer: I am not a physicist, and not a test engineer. If my math or methodology is incorrect, please feel free to tell me why.

about three weeks ago

PostgreSQL Outperforms MongoDB In New Round of Tests

Sarten-X Re:The stress-testing wasn't needed (147 comments)

Was that even transactional?


The live results were restricted to simple queries (mostly for internal reporting), but the workload to be performed ultimately was more straightforward map-reduce algorithms. Everything (live and final) was statistics, so missing a few records due to lacking ACID wasn't ever a real concern.

That almost sounds like a use case for Kx or similar stuff.

It's been a while, but I believe Kx was considered during the initial research phase. Ultimately Hadoop and HBase fit our needs better.

about three weeks ago

PostgreSQL Outperforms MongoDB In New Round of Tests

Sarten-X Re:The stress-testing wasn't needed (147 comments)

I've worked extensively on both kinds of systems over the past decade. Under a particular workload that is exactly what an RDBMS is designed for, an RDBMS has the best performance? Wow, who would have bet on that one?

Then again, I've had workloads (my go-to example is writing several billion records in a matter of hours for statistical analysis, with live intermediate results) where a NoSQL solution had the best performance.

NoSQL isn't some rebellion against traditional databases. Engineering isn't a contest. Rather, NoSQL, column-stores, distributed warehousing, or any other term you'd like to throw out all just point to an additional option for how to manage your data. Pick the right choice for your project, and use it. Don't worry about "web-scale" or "ACID compliance" talking points unless your project needs them. For the past few decades, we've been forced into the assumption that data must perfectly normalized, arranged in tables, and must be queried as relations. For some projects, massaging the data into that form will damage your performance far more than your database engine ever will, so a different engine makes a better choice.

Stop listening to hype, deserved or not, and use the right tool for the job.

about three weeks ago

PostgreSQL Outperforms MongoDB In New Round of Tests

Sarten-X Re:I dipped my toe in MongoDB (147 comments)

So in other words, you dove into a tool you didn't understand, and apparently pushed it through to deployment, before you realized it wasn't even the right fit for your project.

That says a lot about how credible your review is.

about three weeks ago

Bioethicist At National Institutes of Health: "Why I Hope To Die At 75"

Sarten-X Re:The WHO (478 comments)

Is that so bad, though?

Let's say, hypothetically, that if you spend an hour exercising each and every day for 40 years, you can extend your life by an extra decade. Assuming a constant 8 hours of sleep daily, that's a four-fold return on investment!

Of course, due to the effects of aging, it very well could easily take me twice as long to do anything, and I could easily get only half as much enjoyment out of it. Sure, I keep pushing that number higher, but by a self-assessment of how good my life is, I'm only breaking even. Considering the risks associated with aging, is it even worth the investment?

My grandmother has said many times that the only thing wrong with her is that she hasn't died yet. She's well into her 90's, with no serious physical deterioration, but life has gotten boring. Her life-long friends have all died, and many of her new friends have died, too. Her children have grown up and moved on, and so have her grandchildren. She's traveled the world multiple times, and gone on every adventure that she wanted to. She was expecting to die twenty years ago, having lived a complete and happy life.

Now what's left? Seeing yet another round of new miracles being taken for granted by a generation that assumes such technology is a basic necessity for life? Watching $THIS_GUY slaughter $THOSE_GUYS in the name of $SUBJECTIVELY_JUST_CAUSE? Spending another year alone in her home?

More personally, I have a medical condition that will deteriorate rapidly when I hit about 50, and faster if I partake in strenuous exercise. The only treatment option includes the term "replacement vertebrae". Is it somehow morally wrong for me to plan my life such that I spend every waking moment now using my limited health in ways that I enjoy the most? I doubt I'll survive as long as my grandmother, and my condition effectively assures me of problems by that age, anyway. Hitting 75 and signing off sounds like a good plan to me.

about a month ago



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