Archive for category knowledge base

COVID-19: On Wearing Masks

There’s a lot of misinformation going around that spreading the idea that wearing a mask is pointless because it doesn’t significantly reduce your chance of avoiding the disease.

That idea doesn’t address the primary benefit of wearing a mask at all.

Here’s the important thing to understand: One of COVID-19′s major vectors for infecting others is via virus carried on moisture exhaled by infected individuals.

Even a simple mask considerably reduces the range and load you deliver when you breathe out if you have COVID-19. After you’re infected, usually there are 3 to 14 days before you become symptomatic. Not everyone is symptomatic, either; there may be no indication to you that you are infected. When someone is infected, wearing a mask can benefit many, many others while you are infectious and unaware of it, depending on your social interactions, distances, etc. over the course of those asymptomatic days.

If you continue going into situations where others could be exposed after you’re symptomatic and obviously still infectious, masks and social distancing will reduce the rates and severity of infection for others in that circumstance as well. Not that anyone should be out and about when symptomatic if it is in any way avoidable.

The rate of infections is a very important consideration: what we really don’t want is for someone to end up with severe symptoms when the healthcare facilities are operating at maximum capacity as has happened several times already due to people taking insufficient precautions such as masks, social distancing, washing hands, etc. If you need a ventilator, for instance, and they’re all in use, now you are at much higher risk of severe problems consequent to your breathing issue.

Even if everyone will eventually get COVID-19 and have to deal with it, it’s still eminently worthwhile to keep the rate down so those who need care can be certain they will get it.

On the other side of the coin, the higher the load in a healthcare facility, the more at risk the healthcare professionals are; that’s a cycle that even further reduces the facility’s ability to deal with additional cases. Every healthcare professional that cannot work reduces the ability of the facility to care for patients.

Everyone should be wearing a mask and maintaining social distancing. Both significantly reduce exposure of others when COVID-19 is present, and both work to reduce concurrent loading of healthcare facilities. As a bonus, these things also work to reduce the chances of spreading other diseases, such as the flu.

There’s another side to this as well. Although it is true that a simple mask does not reduce the chances of infection for the person wearing it by much, any reduction at all is a very good thing; for instance, if every infected person on average infects one other, and that is reduced to .95, then the disease will slowly recede. That’s enough reason to wear a mask all by itself. Likewise, if every infected person, on average, infects two others, and that can be reduced to 1.95, the load on healthcare facilities drops, which becomes very important when critically ill people need treatment — and that’s true no matter if you have COVID-19 or need your gall bladder removed. There are only so many beds in any one hospital.

  • Always wear a mask when others are present in public
  • Maintain a distance of at least 6 feet from others as much as possible
  • Wash your hands / use hand sanitizer, break “touching-face” habits
  • Don’t spread misinformation

Comparative Mortality

COVID-19 deaths / year: 219,000 and still counting [As of October 18th, 2020]

FLU deaths / year: around 40,000 to 50,000

What is actually causing these deaths?

The critical question to answer here is “What does death from X” mean?

It means if you hadn’t had the primary infection — flu, COVID-19, etc. — you would not have died from whatever actually killed you.

For instance, you may encounter the argument that “people aren’t dying from the flu, they’re dying from pneumonia.” However, when the pneumonia is a consequence of respiratory difficulties brought on by the flu — that’s when it is accurate to say that it was the flu that caused the death. The same is true for COVID-19.

Trying to distinguish a consequent fatal pneumonia from the flu (or COVID-19) and then saying there’s nothing to worry about is as absurd as saying “jumping off the cliff didn’t kill someone, it was hitting the rocks below, so don’t worry about jumping off a cliff.”

The jump was the primary cause of death; without it, the rocks would not have killed the jumper. You should definitely avoid such a jump.

The flu and COVID-19 are both exactly this kind of killer; if someone becomes infected and dies, then a directly related follow-on effect is very likely going to be what killed them, just as the rocks killed the jumper, but if the flu or COVID-19 is avoided, then there will be no consequent pneumonia to die from, either.

Tags: , , , , , ,

Walking for your Lunch

I spend some effort managing my weight. One of the things I do, that most people can also do, is walk. Walking can buy you a free lunch, calorie-wise. Here’s the deal…
Read the rest of this entry »

Tags: , , , ,

Some OS X DHCP Esoterica

Because I develop Software Defined Radio (SDR) software, I have occasion to connect, and disconnect, various network devices to my wired network in order to test them all day long. Most of the SDRs are designed to configure using DHCP, or can be convinced to do so. That saves some fooling around, and is a good thing. However, my network is extensive, devices are always being moved around, WiFi devices arriving and leaving, and so once the SDRs are assigned an IP, I have to go hunt them down. It was annoying that they’re always showing up somewhere different.

However, my Mac Pro had an unused second ethernet port sitting. right. there. Hmmm. So…
Read the rest of this entry »

Tags: , , , , , , , , , , , , ,

NewBurgers!

NewBurgersOk, here’s the deal. I was sitting around one day recently, contemplating having some hamburgers for dinner, and feeling kind of “meh” about it, because I never get them right. They’re too big, they’re too small, they aren’t cooked right in the center, or if they are, they’re overcooked on the outside, they’re too thick, too thin, they shrink too much (some burger is made by mixing shaved ice in during the grind down process in order to increase volume; if that’s been done, the burger will shrink quite a bit when cooked as the water evaporates out.) Anyway, it just never works out. Burgers have been my cooking downfall forever. And I really don’t like those frozen patties much, either. So I thinks to meself, see, “can this be gotten around?” Well, as it turns out, yes, I figured out a way.

The result is fabulous.
Read the rest of this entry »

Catching ALL exceptions in Python

When working with Python, sometimes, more than anything else, you need to know what went wrong. Quite aside from all the debate about what you should do in response, and particularly when developing, you need more than just a vague idea that your CGI bailed and that there might (or might not) be some usable indication of this in the system web logs.

Even when working in a pure command line context, you may need to catch anything and everything. If you do, the following gives you a basic model of just how to do it.

import sys try: a = 5 / 0 except Exception,e: # the Exception class provides messages print 'Exception caught, message: '+str(e) raise SystemExit # bail out (optional) except: # other exceptions e = sys.exc_info() # so we mine sys library info instead print 'Non-Exception class Exception caught, message: '+str(e) raise SystemExit # bail out (optional) else: # and, well, sometimes things work out. print 'it worked, no exception!' # whoo hoo... finally: # always happens print 'Glad THAT ordeal is over -- one way or another.' print 'And here we are. Aren't we?' # you only get here if things worked out

Try out the above with code you know will work, like a=1 immediately subordinate to the try: clause, and then with code you know won’t work, like a=5/0 and see what it does.

Something to keep in mind: The ELSE clause of a TRY block only runs if execution proceeds off the end of the TRY section. So if you have two statements in the TRY section, and the first one runs but the second one does not, the ELSE clause will not execute. The EXCEPT clause will due to the exception. FINALLY always, always runs, even if the EXCEPT clause has an exit in it.

You can think of the ELSE as being functionally equivalent to just putting code right after the TRY-EXCEPT-ELSE-FINALLY sequence if you build an unavoidable exit into the EXCEPT portion. Of course, it’s nice to put related code in, because that makes the functionality and intent more obvious. And if you don’t have an exit there… then ELSE can be quite useful, as it won’t run if the TRY block fails, but the code after the entire TRY-EXCEPT-ELSE-FINALLY sequence will.

Hope someone finds this useful. Took me a while to dig through it all and wrap my head around even the basic idea that sometimes, you just need to know!

Tags: , , , , ,

Headless Raspberry Pi B+ via Ethernet – from zero to success

R.Pi B+ BoadSo (somewhat late to the party, but anyway), I came up with a project I could use a Raspberry Pi for. Off to Amazon I went, and purchased this starter package (select the ULTIMATE kit), which I highly recommend. Everything you need, all in one place. I’m assuming you either bought this kit, or have the things you need, which I will also call out in case you’re a masochist and plan to try to assemble all this stuff by yourself.

Take note that I’ll be updating this post as I discover more stuff about the Raspberry Pi I think is worth sharing; so you might want to bookmark it and come back again from time to time. I’ll try and make it worth your while.

To start, you will require the Pi B+, a storage card with NOOBS on it, a power supply, a wired USB keyboard, a wired USB mouse, an ethernet cable, a free port on your network router or network switch, an HDMI cable and an HDMI capable monitor.

No, there’s no other way. You need the monitor, keyboard and mouse. Sorry. Not my fault. Everything I listed except the network cable, keyboard, monitor and mouse is supplied in the kit I linked to just above. As well as a lot of other really cool stuff. Hint. Hint.
Read the rest of this entry »

Tags: , , , , , , , , , , , , , , ,

Let’s talk Evidence.

One of the common aphorisms we hear in two varieties is, first form, “absence of evidence is evidence of absence”, and second form, “absence of evidence is not evidence of absence.” Either statement seems to make sense on its face; but this is because of a common misunderstanding. In truth, only one form actually works for us within the bounds of reason.
Read the rest of this entry »

Tags: , , ,