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Ask HN: Teach me something new

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Re: Ask HN: Teach me something new

#751

Post by andbberger »

SemanticStrengh wrote: post #672
andbberger wrote: post #668

Earlier quoted context omitted.

i really couldn't care less how many papers you've read. whole brain calcium imaging is routine, no one expects it to be the whole picture. it's useful though. and no it is not a matter of debate, there are precisely 302 neurons

it's useful and yet understanding how brain works precisely require better instruments and datasets hence the understanding of the brain is not bottlenecked on infinite complexity but before anything, on good old metrology. Q.E.D oh yeah well done completely avoiding the PNS question, so according to you neurons in the tail are relevant to worm cognition? spoiler except for tail local stimulus (e.g. tactile, heat) I…

QED is something you write after proofs not incomprehensible sentences. there is a compelling argument to be made that what neuroscience is missing is theory, not data. there is quite a lot of data.

i am dissappointed, although not surprised that someone who relies on appeals to authority when arguing a point is of the mindset that in an organism so finely optimized that it uses biomechanical feedback in gait generation where larger organisms use central pattern generations involving larger number of neurons that some neurons are more important than others. neurons are expensive.

guess you had better read some more papers.

Re: Ask HN: Teach me something new

#752

Post by causality0 »

picklesman wrote: post #462
MaanuAir wrote: post #317

Earlier quoted context omitted.

Thanks for this! As a French, I always wondered why this oddity. That should also be introduced when teachers explain hexadecimal :-)

Me too! Btw, in the spirit of the title of this thread, in English you would say "as a French person". In the past, "Frenchman" was used but it's understandably out of favour these days. "French" can be used as an adjective but not a noun in this context. It's a very common error, I suppose since "français" can be used as an adjective or a noun en français :)

That is wrong. The demonym for a person from France is "French". It only sounds wrong to an English ear because we're so used to calling them Frenchmen, but it's chauvinism on our part, not a linguistic mistake on theirs.

Re: Ask HN: Teach me something new

#753

Post by tmaly »

mfarstad wrote: post #439
ToJans wrote: post #110

I watched a piano/music teaching video from the 60s yesterday that made it all "click" [1] Most modern music chords patterns are easy to find out on piano. Start on any of the white keys, and play 7 white keys left to right. That is called a mode: a series of notes separated by certain intervals to compose a song. Different modes have different vibes. Atmosphere of the song ( sad or happy) is directly correlated by h…

Building off of this to talk about functional harmony (I recommend a book called modeology) Look up roman numeral notation for this next bit. A V-I is called a perfect cadence in the major scale, and pretty much any other mode in which those chords naturally occur. The most important tones are the major 7th, which is one semitone away from the root and has a strong desire to resolve up, and the perfect 5th, which is…

Can you suggest some YouTube videos you have liked on this subject?

Re: Ask HN: Teach me something new

#754

Post by scrollaway »

arc-in-space wrote: post #452
scrollaway wrote: post #316

Take a few minutes to learn the NATO phonetic alphabet Alpha, Bravo, Charlie, Delta, Echo, Foxtrot, Golf, Hotel, India, Juliet, Kilo, Lima, Mike, November, Oscar, Papa, Quebec, Romeo, Sierra, Tango, Uniform, Victor, Whiskey, X-ray, Yankee, Zulu Gotta spell anything over a voice line? Use it. No more screwing around with "B.. like Bryan, and then U, like .... under". s-c-r-o-l-l-a-w-a-y: sierra charlie romeo oscar lim…

A few minutes? Ha, no way. I think it'd take me at least a few days of short deliberate practice sessions to actually memorize this from scratch. Also, useless outside of the US. (I'm whining, but I do think this is cool.)

I have never lived in the US :)

Re: Ask HN: Teach me something new

#755

Post by yobbo »

schoen wrote: post #750
yobbo wrote: post #717

Earlier quoted context omitted.

Mensch, människa, menneske, ..., and (most likely) manusha are cognates. But it's still curious how "manusha" sounds like "människa" while the vowels have been dropped in "mensch".

For some reason German sometimes drops the i in "-isch" (cognate with English "-ish"). But the only reasonably common examples I can think of are Deutsch (etymologically definitely with -isch/-isk) and Kölsch ('pertaining to Cologne'). I don't know if this is somehow an example of a more widespread phonological process in German.

In Swedish, "isk" endings are sometimes contracted to "sk" such as "polsk"="polish" and the only way to say "pertaining to Köln" would be "kölsk" (unless specifically the beer.)

But "människa" is a noun. It's pronounced "menisha" but it doesn't mean "manish". In Norwegian, the word for humane is spelled "menneskelig" literally "menneske-like". (In Norwegian the 'k' is hard.)

As I can gather, the literal meaning in sanskrit of "manusha" = "born of Manu" = human. Manu is a god.

Re: Ask HN: Teach me something new

#756

Post by cx42net »

CGamesPlay wrote: post #219
mikelevins wrote: post #28

I've described this on HN before; forgive me if you've already seen it. I have chronic migraine. It sounds worse than it is; I rarely suffer attacks anymore, and when I do, they're usually mostly harmless, as in the case I'll describe below. Contrary to popular belief, migraine is not a headache. It's something a little more like an epileptic seizure. Intense headaches are one common symptom, but there are a lot of o…

Interesting. I get these scotomas about every 6 months or so, usually lasting for 30 or so minutes. I was told they were called "ocular migraines", and a cursory glance over the internet doesn't seem to help me differentiate between the two, although I will say that [0] is a very accurate depiction of how it looks when it happens to me. I normally just take a break from whatever I'm doing and go for a walk. The first…

One time I was at a friend's house with my laptop and lowered the screen light during the night but forgot about it. The very next day, while working, I started to get that "aura" migraine.

In general, when this occurs, I stop doing whatever I'm doing, take a ibuprofen pill and go to bed for 20 minutes. After that, I have a massive headache but no aura.

What was odd is that the very next day, I got the same migraine, again! This rarely occurs to me (two days in row).

It was later that I realized that the screen light was low and that might be an explanation about why I got two migraines in two days.

Hopefully it can help someone else here :)

Re: Ask HN: Teach me something new

#757

Post by runjake »

iod wrote: post #278
runjake wrote: post #31

There are no aliens[1] or alien technologies at Area 51. 1. Other than a gag mannequin or few.

Edward Snowden, who had access to basically all the US governments secrets for NSA and CIA with the highest above top-secret clearance, went specifically looking for stuff related to this and says that he came up with nothing. Out of anyone who could know things about this, I find his situation and argument to be most convincing.

Perhaps, but there's all kinds of tangentially-related stuff that could have been leaked but wasn't. Nor was mentioned by Snowden. One already-public example being the 2004 Nimitz incident, which is of genuine national security concern.

I know Snowden is highly-revered around here, but he's not all-knowing, and I'm fairly certain he did not have access to the entire US IC store of intel.

Re: Ask HN: Teach me something new

#758

Post by Beta-7 »

greazy wrote: post #426
Beta-7 wrote: post #344

Earlier quoted context omitted.

Out of all the hobbies I've had, electronics (mostly something to do with the ESP microcontrollers) is the most satisfying one once everything works as intended. While electronics knowledge is hard to learn on your own (in my case), there are tons of communities online that are more than willing to help.

What communities do you recommend?

I tend to float around the "Electronicity" and "Digital Hackerspace" discords. Other than those there's subreddits like r/AskElectronics, r/electronics, r/esp8266, r/esp32 etc. Sometimes people advertise their discords there and I like to pop in and see what they offer (how I found out about the previously mentioned discord servers)

Re: Ask HN: Teach me something new

#759

Post by euroderf »

Contexti wrote: post #645
euroderf wrote: post #511

Earlier quoted context omitted.

In IE languages, the words for water basically follow either "aqua" or "water". Finnish (it's Ugric, not IE) follows the latter, with "vesi" (combining form "vete-").

To be pedantic, Finnish is not Ugric. Hungarian is Ugric, Finnish is Finnic. They both are Finno-Ugric, a.k.a Uralic. Many non-linguist Finns mix up Finno-Ugric and Ugric. The Proto-Uralic * weti "water" looks like it could come from IE * u̯ódr̥ , * udén - "water", but that etymology is problematic because of irregular sound substitutions[0]: - why would Uralic have * e when it's not present in the IE original? - why…

A-ha, good to know. And sori on the "Ugric".

As for irregular sound substitutions, well, water IS a very common concept & word, so I would think that anything goes.

Re: Ask HN: Teach me something new

#760

Post by GranBurguesa »

ajb wrote: post #229

In statistics, the mean and median are both averages, but are technically quite different. The mean is the sum of all items divided by the number of them, while the median is the middle item in the sorted list. When they are different, this can have strange effects. For example, when estimating engineering tasks, the mean error is often positive while the median is often negative. This is why your manager believes th…

i found the concept of https://en.wikipedia.org/wiki/Fr%C3%A9chet_mean helpful. it's a generalization of the different kinds of averages and you can express the arithmetic mean, geometric mean, harmonic mean, median or even mode just by swapping out the distance metric in the formula.
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