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Comment Re:What? (Score 4, Informative) 14

Hi, I've used a FuelBand (SE+) for a year or so.

They do log / track locally. There is enough onboard memory to store several days' worth of activity, in one minute increments as far as I can tell. (I only sync my data once a day when recharging by USB, but I've often gone a few days between. All the data make it home.)

Moreover, the FuelBand has a display that gives real-time feedback: it can give you move reminders if you've been still for too long, or "encouragement" if you start up. (I've disabled this feature on mine.) It makes a little animation when you've hit your daily goal. You can press the button to get statistics on Fuel (more on that in a moment), number of steps, and number of "hours won" (hours with at least several minutes of continuous activity) at any time in the day.

So yes, there is local storage, tracked minute by minute, accessible on demand for visual feedback. It can communicate via Bluetooth with an Android phone or iPhone for a bit more capability. (The button broke on my FuelBand, so this is my sole means of real-time communication with the device.)

I'd imagine that where they might have had more trouble is the "health" than the "tracking". They use an arbitrary unit called "Fuel" that correlates well with physical activity, but tries to scale many types of activity onto a single unit of measure. I've noticed that on very inactive days (couch potato sick day), I'm under 1000 Fuel. On a moderately active office day where I take a walk in the afternoon, 2000-2500. On days where I go for a run, 4000-5000+. It seems to scale well. But they may not have enough trials and other tests to validate that tracking Fuel means tracking health.

Comment Re:Web sites (Score 4, Informative) 277

Here's the TRUSTe info:

It only seems to cover security/privacy of their ecommerce site. So, their shopping cart may be secure, but it says nothing about app security as they seem to imply in their press releases, etc.

Comment Re:Is FORTRAN still winning? Was Re:Poor Alan Kay (Score 1) 200

Repeatedly allocating and deallocating can give a huge performance hit, so I tend to do all my allocations before the main loop. Not entirely sure why the penalty is so big, but it seems to be - these are allocations of hundreds of MB or even a few GB, so the cost of operations done on the arrays should dwarf the cost of the allocation.

It's a hardware thing -- the memory bus and memory read/write speeds are still a limiting factors, particularly as CPU cores get faster and more efficient. In any code, memory operations (allocations, copies, and deallocations) are performance killers and best avoided wherever possible (e.g., pre-allocating memory as you are, using temp variables that don't get deallocated, overloading operator+= operations to avoid hidden allocation and copy operations, etc.) The general rule:

[Disk access] is much slower than [memory access] is much slower than [CPU operations] (esp. those in the cache)

FWIW, I'm writing big finite volume codes in C++ (preparing for an open source release), and we deal with these very same issues. Our biggest performance gains (outside of choosing stable algorithms without time step restrictions and using OpenMP) are from avoiding memory allocations and copies, working on vectors of variables rather than individual variables, overloading things like operator+= on std::vector, and using BLAS (particularly axpy). Also identifying any operations that can be pre-computed (like certain steps in Thomas solvers) is helpful. :-)

Comment Re:Not for deaf/hard of hearing... (Score 4, Insightful) 579

I've encountered these, and I'm told they're pretty loud.

I'm a fairly young guy (37 yo) with perfect hearing below about 1500 Hz, and almost zero hearing above 2000 Hz. To me, these loud clicks are tough to hear unless close up.

I run into the same problem with high-pitched fire alarms (most of them), the "you left your headlights on" beep, seat belt beeps, kitchen timers, the little beep on my FasTrak transponder, etc.

This is probably a widespread problem--we tend to lose hearing in the higher frequencies first. The solution isn't to use annoying high pitches and make them louder; the solution is to use broader frequencies or use lower pitches that more people can hear.

Please keep this in mind when you're considering using a little chirpy piezoelectric in your next circuit project ...

Comment Re:'Radiation Free' (Score 1) 35

I suspect the real story here is likely finding a good target (SFRP2), more so than the microbubbles. Finding a specific enough target always seems to be the limiting factor in immunotherapy, nanoparticle-based drug delivery, GNP-based radiothermal therapy, etc.

Now if they could find a good target for more cancers (I definitely agree on breast as a good target--elastography ultrasound is already a big topic of interest there), it could have a nice impact on treatment options. Since you can't really image too frequently by MRI, CT, etc. due to exposure limits, you can't do high-frequency watchful waiting, which biases clinicians and patients towards intervention when they detect something.

In breast cancer, this is a pretty hot topic: all these frequent / early mammograms are detecting lots of DCIS, and the standard thing to do is lumpectomy. But there's growing evidence that these are likely being overtreated, and many if left alone would likely not progress to invasive carcinoma for a long time. But since there's no great way to know on a patient-by-patient basis, and since you can't really keep a close eye on them by frequent imaging, it's tough to do otherwise.

But if you could image the breast cancer really well by ultrasound, you could do such a watchful waiting: image frequently, and so long as there's no change, keep monitoring. (Not sure if this would have have the resolution to detect an in situ cancer like DCIS, though. Will have to read the article.) It would be nice to see such watchful waiting options open up for other cancers where treatment choices are perhaps otherwise unclear.

I've also seen early work attempting to use interference patterns in ultrasound (putting a few piezoelectric membranes at the right spacing, etc.) to induce apoptosis at specific spots. It would be interesting to see if this work could help enhance that ...

The life of a repo man is always intense.