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jbrot

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The section on marijuana is particularly interesting. You are apparently allowed to deduct ordinary business expenses, even if the business in question is illegal. However, Congress has explicitly disallowed these deductions in the case of illegal drug trafficking. Since marijuana is illegal federally, the courts have ruled that medical and recreational marijuana businesses that are legal under state law may not deduct any of their ordinary business expenses from their federal taxes.

From the title I was expecting something about Op Sec, but the article is actually about “show, don’t tell” i.e. that it’s really hard to have people “get it” without letting them experience “it” for themselves

From the underlying paper[1], I found this excerpt:

“The photocurrent or the short-circuit current density (JSC) extracted from BTO is around 0.415 μA/cm2. … The JSC value from SBC555 is around 11.03 μA/cm2 and is about 25 times higher than measured in BTO. The open-circuit voltage (VOC) in the case of BTO was found to be around −0.007 V, as opposed to −0.058 V in SBC555.”

Here, BTO is the existing material and SBC555 is the new material from the paper. Multiplying JSC by VOC to get power density , we see that BTO yields 2.9 nW/cm^2, while SBC555 yields 639.74 nW/cm^2.

For reference, according to [2], we have that “typical external parameters of a crystalline silicon solar cell as shown are; Jsc ≈ 35 mA/cm2, Voc up to 0.65 V.” Notice the unit difference of mA/cm^2 here vs uA/cm^2 above. Multiplying these parameters yields 22,750,000 nW/cm^2. So we see that these cells are still approximately 100,000x worse at producing power than the current crystalline silicon cells.

[1] https://advances.sciencemag.org/content/7/23/eabe4206

[2] https://ocw.tudelft.nl/wp-content/uploads/solar_energy_secti...

Very surprising to see this headline (although I doubt it will come to pass). Given recent movements towards ending the war on drugs (e.g., legalizing Marijuana), it seems rather hypocritical to then try and ban cigarettes. Admittedly this is in the UK, and I’m not super familiar with their politics.

It means using `git merge --squash` which performs a normal merge but then instead of adding a merge commit, it just makes a single regular commit with the changes.

GitHub Copilot 5 years ago

Programmer discipline doesn’t scale

Thank you for putting this so eloquently. This has basically been the sole tenet of my programming philosophy for several years, but I’ve never been able to put it into words before.

Very neat project! One question about content addressed programs: how does this play out with types that are structurally equivalent but semantically distinct?

For instance, assuming C definitions, an integer and a file descriptor have the same content but probably should not be treated as the same type (I wouldn’t want arithmetic to type check against file descriptors…).

Another scenario: say I have a type “Foo” which contains an integer. In version 1 of my library, this integer must be even, but in version 2 I add support for odd integers, too. The Foo data type, from a content perspective, is unchanged. However, the invariants around it have changed and it’s therefore essential that it becomes a new type. Otherwise, someone might create a Foo containing an odd integer using the version 2 API and then pass it to a function from the version 1 API, resulting in bad things since the version 1 API believes Foo can never contain an odd integer.

From reading the article, it sounds like NVMe-oF exposes a drive directly to a network, but I don’t really get how that works. Does the drive still get connected to a host? How does this compare to other technologies for having networked storage, like NFS?

Yep, likewise it’s also disabled in function calls and sub shells that are invoked in an && or || block (i.e., in the above case of you change the if statement to “fn && echo ...” you’ll see the same behavior).

Even worse, you can add the line “set -e” inside the function explicitly re-enabling it and it still won’t change the outcome because errexit wasn’t technically unset!

Presumably because the financial institution sends the email directly to your email provider via SMTP while your wife sends the email to her email provider via a mail client protocol like POP3 or IMAP, and then her email provider forwards the email on to your email provider via SMTP at its leisure

The claim “you’ve only got time to read a few thousand books” surprised me, but some back of the napkin math strongly supports it. Assuming it takes a week to read a book and 70 years of literacy only gives you time for around 3500 books. A more avid reader might average, say, 3 books a week—-but then you only get to around 10,000 books. Now, a monk might be able to read 30 books in a week and get to 100,000, but pragmatically “a few thousand” seems to be an accurate accounting for a person who doesn’t dedicate a large portion of their life towards reading.

Reading this made me think of Sartre's The Republic of Silence [1]. In this article, Sartre claims, "never were we more free than under the German occupation." He explains that, roughly, in the face of death, each choice becomes more meaningful, more "authentic."

This goes along with the article's discussion of how doctors, in general, choose to receive far less care than the typical patient when faced with terminal illness. This choice grants an opportunity to live authentically, in Sartre's parlance, for their last months as opposed to going out via the indignity of excessive treatment (e.g., life support machines).

[1] https://www.theatlantic.com/international/archive/2014/09/pa...

That was a fun read, thanks for sharing! Rather amusing to see how the 1959 story imagines money in 1996—Knox notes each researcher on the moon base costs “90 dollars a day” implying that that is a huge expense.

I don’t know too much about sneakers, but that is how the nomenclature is used with watches, at least. There, a gray-market purchase is a purchase of a legitimate item from somewhere other than the manufacturer or an authorized retailer. Notably, gray-market goods are sold at a discount but lack the OEM’s warranty.

I don’t know about never regretting. “set -e” is the right choice the vast majority of the time, but definitely has some gotchas to it. For instance, what does the following script print?

  #!/bin/bash

  set -e

  (
   echo "Start of Subshell"
   (exit 1)
   echo "This shouldn’t run, right?"
  ) || echo "Subshell failed"

Stora Karol, a Swedish island, is a popular bird watching destination. This year, the birdwatchers didn’t arrive because of COVID-19. This caused the local white-tailed eagle population to remain abnormally high, as the eagles normally leave in response to the uptick in visitor traffic.

The increased eagle population, in turn, caused the island’s common murres to be displaced from their nests (fleeing eagles) an average of 602 minutes per day—vs. the average of 72 minutes in 2019. Consequently, 26% fewer common murres hatched this year compared with the decade average.

It’s fascinating to see the unintended impacts humans can have in an environment even when thinking of ourselves just as observers.