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danieltrembath

119 karma · joined August 5, 2013

[ my public key: https://keybase.io/danieltrembath; my proof: https://keybase.io/danieltrembath/sigs/oIK5y1TbUJaEVDkZ7VwYzpo-l_zHJbfsNckBJyhw_jA ]
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danieltrembath··on VisiCalc on the Apple II
AppleWorks/ClarisWorks?
danieltrembath··on Examining the covidtests.gov architecture
Same thing here. Site seems down. I'm accessing it internationally, without a VPN.

To further the learning, can anyone guess which part of the stack is likely generating the error?

danieltrembath··on Ask HN: Building a startup while working elsewhere and parenting?
Small software business owner/developer echoing the others here.

I'm 40+ and have a child under 4. When they were born I cut my work back to 1/3 so that I could be a home dad.

It's the best decision I ever made and well worth the (real) financial pain. I can't convey in this text box how fulfilling being a dad has been. This is a time and joy you can never get back. Your kid will be better off from time they spent with you than what the money could have bought.

Raising a kid is a never ending exhausting slog. Two parents that can do everything means you can both get some mental respite. I'm sure our relationship would be worse now if I'd been away working every day. You get to know a lot of other parents and the tension provider/parent puts on relationships is real.

There are downsides. With my wife and I both working part time (nights, naps, 2 days of kinder) we are going backwards financially, but we will survive until school when I'll go back full time. I'm extremely grateful to work in an occupation where that's even possible.

danieltrembath··on What is ‘elite overproduction’?
I discovered Robin Hanson around 3-4 years ago. I read one of his books, through his blog, and his twitter musings and polls.

Often he would question something fundamental about human interaction that seemed to me (and I suspect most) to have obvious and quite simple explanations. But he is intelligent and couldn't be missing the forrest for the trees I told myself. Clearly he must be operating many steps ahead. Levels above!

Now I wonder if maybe he just isn't so good with trees.

I do not mean to dismiss the entirety of his work. No doubt much of it has been valuable. He seems to struggle to understand people, in much the same way as one of the alien's he's obsessed might struggle.

danieltrembath··on The Future of Group Messaging
+1

It was visually a pleasant read.

danieltrembath··on Bringing civic tech to Taiwan's coronavirus pandemic response [audio]
Audrey Tang (featured in the audio) conducted a long form interview with Tyler Cowen a few months ago in which they talked about this kind of civic development.

https://conversationswithtyler.com/episodes/audrey-tang/

danieltrembath··on The Final Airbus A380 Has Been Assembled
"Wait…I'm worried what you just heard was give me a lot of balls screws. What I said..."
danieltrembath··on When you browse Instagram and find Tony Abbott's passport number
"...I called up and was all like “yeah bloody g’day, day for it ay, hot enough for ya?”. Once the formalities were out of the way..."
danieltrembath··on How Pulse Oximeters Work (2015)
bearsnowstorm, I just had a chance to read your background. If you or your department is interested in talking with our emergency specialists by all means say hello.
danieltrembath··on How Pulse Oximeters Work (2015)
Thanks httpsterio. I checked in with the team and posted the details further up the chain.
danieltrembath··on How Pulse Oximeters Work (2015)
Thanks for querying this. I raised it with the team and their response is up above.
danieltrembath··on How Pulse Oximeters Work (2015)
Thanks everyone (below) who was concerned about whether the 42degrees figure was too high. A doctor on the team confirmed that figure was on purpose, but for peculiar reasons, and was kind enough to offer a few pages of explanation which I'll do my best to summarise. Any errors below are mine, not theirs.

The purpose of the program is to watch a large population of COVID patients who are not sick enough to warrant being in hospital. Miserable no doubt, but OK. The purpose of the monitoring is to identify those who are getting sicker before they have become very sick.

The goal is not to have the system calling ambulances. It can (and has) but we should be spotting degradation and reacting before it comes to that. To that end we measure three vitals (temperature, heart rate and oxygen saturation). They are not each equal predictors of the sickness we wish to spot. They are also not linear indicators of sickness.

We have three levels of response to patient vitals. There are some automated suggestions for patient comfort at the bottom end. There is the metcall at the top end. But the most important is the Clinical Review in the middle. Clinical Review connects the patient with a clinician by phone so that we can dig into their situation.

Temperature it turns out is not an especially good marker of the sickness we need to find in the group of people we are monitoring. "[with temperature] there is a U shape association with mortality, but the error bars at any point a super wide". It has some correlation, but high temperatures are not a good enough predictor of what we're trying to spot. Oxygen Saturation is good because of what COVID can cause in the lungs. That can happen without the patient being aware of it so it's critical to what we must spot.

Infection alone wont bring someone up to a temperature that high (we're monitoring people with covid, not amphetamines overdoses or desert marathons). So COVID monitoring is not dependant on spotting patient temperatures that high, and if it was that high it would not be on account of the virus. For those patients this isn't the only healthcare the patient is involved with.

So why do we bother to give the patient a thermometer? It's easy to measure. The devices are cheap and readily available. It's useful at the slightly-elevated end and helps us recommend paracetamol if/when appropriate. Tracking a patient temperature over their monitoring period feeds data back into the ongoing analysis of the virus. We ask a number of supplementary questions of the patients each day. Hopefully there will be trends.

So finally, why is there a temperature threshold at 42 degrees? More an accident of the project history. We'd built the multi-step thresholds for each of the measurements, but it turned out the highest temperature one really isn't applicable in our project. The patient hits Clinical Review well before they get up to those temperatures. It may come out completely in a newer version.

Also they added "Whilst not completely analogous, we draw your attention to the NEWS2 illness scoring system used by the National Health Service (UK) (https://www.mdcalc.com/national-early-warning-score-news-2). The system uses various parameters to calculate a score of 'how sick they are'. Whilst many measurements have a 3+ (add 3 to the score) threshold values, the NHS does not have a temperature threshold value 'worthy' of contributing 3 points to your illness score."

danieltrembath··on How Pulse Oximeters Work (2015)
That is a very good point :)

The figures are actually set per-patient. But that 42 as placeholder does seem odd. There are two lower thresholds that trigger before getting to that one. But I’ll flag it with the clinician regardless. Thank you.

danieltrembath··on How Pulse Oximeters Work (2015)
There is a tool for screening patients as they arrive at the hospital. This has been running at a number of facilities this year.

https://github.com/rmhcovid/screentool

And we have another project for operating drive-through testing clinics that will hopefully be published in the next few weeks. It has been shared through hospital channels but isn’t up on github yet.

danieltrembath··on How Pulse Oximeters Work (2015)
Chosen by the emergency doctors who headed the project. Sats being the more important. Those are default thresholds, but each they can be overridden per-patient.

As I understand it there is a lot of communication going between emergency teams and specialists around the world and the odd pre-publication paper. This work has come out of the RMH's emergency department. Full credit goes to Dr Martin Dutch who's idea the whole thing was. As best I know he came to the idea (tracking sats via cheap electronics to spot risky covid patients) quite early, and independently. He also built an initial prototype. I'm a developer who was brought in to build it out into a working system during the first phase of Australia's covid outbreak.

PS: If you're thinking about using the system, it's worth having a read through the redcap_design_overview.md documentation. Building something like this in a research-survey tool was not easy and there's plenty of things in the design that will be head-scratchers when seen for the first time. Now that the model is proven we'll hopefully build out a 'real' version of it at some point.

We're happy to assist where we can to see other hospitals (particularly resource-constrained ones) pick it up. The operating costs are very low (a server + sms gateway cost). The hospital has also open sourced some other covid tools developed this year.

danieltrembath··on How Pulse Oximeters Work (2015)
The Royal Melbourne hospital in Australia is using pulse oximeters to manage COVID positive patients in their own homes. The program was setup in March this year to manage a large number of patients remotely (cost/safety).

The patients take their own measurements with a pulse oximeter and digital thermometer (both off the shelf consumer items). The person is prompted via SMS and submit their vitals via website. A software system orchestrates all of this and alerts patients and clinicians to anyone with worrying numbers.

This keeps beds free at the hospital, but still gets the small percentage of patients back to hospital that get really sick.

It also does all the other boring monitoring and administrative work needed when you're checking up on lots of real people.

Full disclosure. I worked on this project. A version has been open sourced and if you're a hospital or other medical service you're welcome to use our work. We're publishing improvements as we go. https://github.com/rmhcovid/txtmon

https://www.thermh.org.au/news/royal-melbourne-hospital-impl...

Using simple standalone devices and a low-coding platform already in use by hospitals (REDCap) the whole project was crash-built in a couple of weeks and is saving lives. That platform has many shortcomings (messier even than Excel), but there's various medical/privacy rules that make more traditional development unattractive for quickly prototyping. It's been a rewarding project to work on despite many frustrations.

danieltrembath··on What concept would improve everybody's cognitive toolkit? Kayfabe (2011)
Or that the article author is Managing Director of Thiel Capital.

I'll grant this is getting into Ad hominem territory, but I point it out because an 'it's all just a performance' viewpoint seems kind of worrying when you wield signifiant influence.

danieltrembath··on DARPA Wants Millions to Design an Unmanned 'Flying Gun' Under Its New Gunslinger
This stood out to me also. $13million is a tiny sum in military research. Seems like a pretty limited research project.
danieltrembath··on Ask HN: What books changed the way you think about almost everything?
Same. Almost every time I see a can the phrase 'best shim stock in the world' jumps into my brain!
danieltrembath··on Do I Offend?
This comment should be even higher. He never misses an opportunity to promote his books (and I don't blame him for that). But imo he's happy for a bit of controversy.
danieltrembath··on New bridge collapses into river in eastern Saskatchewan hours after opening
2018 alone has enough content for Henry Petroski's next book.
danieltrembath··on Ask HN: Favorite teachers on YouTube?
This is a great suggestion even if you're not a big gun person. I'm not a firearm owner but the detail and historical context in Forgotten Weapons is fascinating. Check out the sister-channel In Range as well.
danieltrembath··on A Dutch first: Ingenious BMW theft attempt
I wonder if they were in fact intending to steal the airbag, but were disturbed in the process. Airbag theft is fairly common and lucrative. You can extract the A-Pillar bag through the window without opening the door. In cars without the radar/pressure sensors you have some chance of doing that without setting off the alarm.
danieltrembath··on Ditch the Batteries: Off-Grid Compressed Air Energy Storage
Unfortunately there are downsides, but compressed air vehicles are already a thing.

https://en.wikipedia.org/wiki/Compressed-air_vehicle

https://en.wikipedia.org/wiki/Compressed_air_car

danieltrembath··on SFO near miss might have triggered aviation disaster
Adding to that, "Normal Accidents" by Charles Perrow is a great read.
danieltrembath··on Up a Wombat's Freckle
Holy shit, I was born in the 'rat and had no idea we birthed chunder.
danieltrembath··on Scientists record biggest ever coral die-off on Australia's Great Barrier Reef
I'm not entirely disagreeing with you, but I'm Australian and I was around in the '80s, and there were warnings for the barrier reef then too (in the context of greenhouse effect, and also CFCs and crown of thorns).

Sadly for your casual climate denier they interpret this as 'meh, they've been saying the reef will die for years, and it's still here'.

I don't agree with that thinking, and I understand that the threats then are a mix of the same and different ones now. But the '80s were no more enlightened on the matter than now.

Don't mind me. The older I get the more I grump at people's perceptions of the past ;)

danieltrembath··on Web Scraping in 2016
Another 3000'nder. Would be great to see this turned into a talk somewhere.
danieltrembath··on Ask HN: Oldest code you have written that is still in use?
2002. Intranet for a major auto maker. Still going strong. Large percentage of the original management and accounting code intact. Still in development.

1999. DynamicIP tracking script from the dial-up days. Tiny but it's been telling me where my home internet is for 17 years.

danieltrembath··on Ask HN: Australian freelancers, how're you doing?
Ha. Nah I'm not from here originally.

If you want to say hi danielt @ room52 net

If you're not already involved in the weekly programming night scene (checkout what's available on meetup and lanyard) then that's a great way to meet other developers and a lot of other freelancers.

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