Good to see that he tells it like it is — you won’t hear any mention of this stuff from the administration at Tulane, you’ll just hear a pile of euphemisms, but we (who were or are there) know it to be true:
Category Archives: Biomedical Engineering
Ectopic Beat Becomes a Spiral Wave
I found this neat video on YouTube today when looking at some related videos to my own. This shows how an ectopic focus in the heart can develop into a spiral wave.
The Engineer’s Conscience: Doing the Right Thing
There’s a long and (two-year-) old screed over on K5 entitled How I Was Saved ostensively about the proper way to write C++ code. I actually found it in my trove of old bookmarked to-read articles using Readeroo. In it, there’s a very good, very penetrating thing said about the responsibility of engineers to do the Right Thing:
Because an engineer named Roger Boisjoly didn’t trust his conscience, seven brave and innocent people died. No, he followed standard procedure, by reporting a safety risk to his superiors, then trusted them to do the right thing, despite the fact that they obviously didn’t heed his warning:
It got real cold one night when the Space Shuttle Challenger was being readied for launch. The Shuttle’s two solid fuel rocket boosters had been manufactured by Morton Thiokol in several sections. Rubber O-rings were used to seal the joints between each section, and covered with high-temperature putty to protect the rubber from the flames. But the rubber the O-rings were made of became stiff if it ever got cold. It wouldn’t flex as the sides of the joint vibrated in and out, so that the flames inside the rockets might shoot out through a crack, and make the liquid fuel tank explode.
Realizing the risk, Mr. Boisjoly filed a safety report with his superiors, yet despite the fact that they overruled his advice for fear of losing Morton Thiokol’s fat government contract, he did his duty to his company and kept quiet.
But he didn’t do the right thing when he realized the Challenger was going to launch to its doom. Why didn’t he ring someone up at NASA? We didn’t he go to the press? Why didn’t he crash his way into Mission Control, arms flailing and screaming “IT’S GOING TO FUCKING EXPLODE!”?
Because he might have lost his job? He probably would have, but I don’t think that’s why. Gotten arrested? No. I don’t know for sure, but I’ll hazard a guess: either because he trusted his company to do the right thing or because he didn’t want to get blacklisted. And because he didn’t trust his conscience, and go against orders – no, not even that – against standard procedure, he has these people to answer to, and their loved ones:
* Francis R. (Dick) Scobee (1939-86), Commander
* Michael John Smith (1945-86), Pilot
* Ellison S. Onizuka (1946-86), Mission Specialist One
* Judith Arlene Resnik (1949-86), Mission Specialist Two
* Ronald Erwin McNair (1950-86), Mission Specialist Three
* S.Christa McAuliffe (1948-86), Payload Specialist One
* Gregory Bruce Jarvis (1944-86), Payload Specialist TwoSomeday you might be faced with such an awful decision. Most engineers don’t ever consider the possibility. I’m asking you to consider it now, ahead of time, so if the time ever comes, your mind will already be made up.
Preceding this is a tale of how the author learned to do things right from his father. I’m proud to say that I learned something similar from my father. He’s always been willing to put forth the time, effort, or money to do something the right way the first time, and that’s an example that’s served me well. I haven’t always been able to pull it off, and there have been times when I’ve forgotten how important it was. I suffered the consequences of cutting corners those times, and was reminded of the lesson. I’m just glad those reminders were not at the expense of someone’s life, much less the lives of seven people.
It all begins when the gates open.
Maria has an excellent little vignette about nerve firing (which is very very similar to cardiac cells firing) over at intueri. Here is an excerpt (whose prose is typical of her excellent writing):
Sodium ions flood into the single brain cell through the gates of channels linking the exterior and interior of the neuron. Other channels along the length of the cell follow suit, opening more gates to allow more sodium ions in. A deluge of positively-charged atoms overtakes the single cell.
Other channels follow the precedence, though they selectively permit calcium, not sodium, ions to join the influx. The excess positive charge soon beckons the potassium channels to open and, with gusto, potassium ions flee from the interior of the cell.
Whew! Jobs running on the cluster. (And travel.)
I’ve been totally absent from most of my life the last week as a result of some problems we had with our code on the cluster. My jobs kept dying, taking down compute nodes in the process, for no apparent reason. After a while I narrowed it down to the time when restart files (from a previous simulation) are read. It turns out that the way the files were read (and that way for a good reason) was really brutal on the network. It involved way too much communication. This was okay for smaller models, but I currently have the largest model we’ve ever run in the lab.
After a conversation with our current programmer and one with our former programmer, and about 6 hours of coding last night, the restart files are now read in a less naughty way, and my jobs are reliably running.
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Tomorrow I am leaving for about two and a half weeks in New Orleans and Mandeville! I have an early flight, preceded by an even earlier train ride to the airport. I should be hooked up to the “tubes” and (New Year’s resolution here I come) updating the blog more often with the blow-by-blow as I try to get enough data for a Heart Rhythm conference abstract in time for the deadline, despite all of the sundry delays with the cluster.
*gasps for breath*
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Also, Penguin liked my cluster video so much that they put it on their front page.