kortex

A pipettor is an agent which does the pipetting, usually this is the scientist when manually pipetting, but there are autopipettors which are robots.

Pipettes are originally the glass tubes of fixed or graduated volume, but the definition has expanded to include air displacement pipettes aka "micropipettes" (even when the volume is measured in milliliters not microliters, they are still colloquially micropipettes).

I've gone through a box a day at peak just doing regular chemistry (biochem uses way more) so I completely believe it.

It's not like one pipet tip a minute. It's more like, you have N source vials and M destination vials/wells/rows, and you'll do that several times a day, interspersed with other processes. A cycle goes like:

10 New tip

20 Suck up sample from source n

30 Dispense into m-sub-i

40 while you still have destinations for the current solution, goto 20

50 eject tip

60 goto 10

This cycle takes maybe a few seconds to half a minute. Also multiply number of tips by P if you have a multi-tip pipette.

FYI, just a friendly reminder: HN culturally isn't reddit and low-effort comments with just a video reaction usually don't do well here.

Ok, so make sure you get enough dietary manganese?

RDA for Mn is 1.8-2.3 mg/day. Tolerable upper limit is 11mg/day. Mn ions are highly conserved in the body and mostly cycle through redox states and various complexes.

That's actually a pretty narrow therapeutic window, again because it's a trace mineral and biology has evolved to recycle it very efficiently.

So then why are you being so contrarian? The overwhelming evidence supports the theory that a combination of strength and cardio training leads to better healthspans. And before you "correlation is not causation" yeah no duh, but the evidence is absolutely conclusive by now that exercise is better than not.

> What the hell is muscle use above a curent baseline? What does that even mean?

Meaning, a conservative increase over your current training regimen, as opposed to over-training. If you go from couch potato to running several miles a day, that's going to be way more stressful than gradual ramp-up. I made that caveat because intense over-training can cause really bad things such as rhabdomyolysis at the extreme.

>I’m pretty sure you’ve never taken a science class in your life.

I'm pretty sure I have a BS in chemistry and worked as a synthetic chemist for years, and you are talking out your ass.

Reactive oxygen species (ROS) is loosely synonymous with "free radicals", which is more of an older term. ROS include free radical oxygen, but also other energetic non-radical species such as singlet oxygen and peroxide ions.

But yeah, your broad point is correct. Biology has several billions of years of evolutionary experience dealing with ROS and upregulates antioxidant biomolecules in response, it's way more complex than "ROS bad".

> Although initial investigations reported the negative effect of ROS, recent studies have shown that exercise-induced ROS can upregulate several enzymatic and nonenzymatic antioxidants in the biological system [7, 8], and exercise could be an optimizer of ROS in negating oxidative damage in the cells, while ROS can regulate signaling or act as a signaling molecule to muscular adaption.

Did you even read your own link, or are you just googling keywords and linking papers with a title that superficially supports your thesis?

Strength training isn't the same as chronic distress though. Activity that uses muscles above current baseline leads to inflammation, which leads to hypertrophy and growth, which results in downregulation of inflammatory markers in the long term. The body upregulates anti-oxidant species in response to normal increases in oxidative stress. Yes, acute/extreme spikes in ROS generation is bad, but that's not what actually occurs in regular exercise.

Tomes of papers support the connection between physical activity, reduced inflammation markers, and decreased all-cause mortality.

Maybe you should actually take some courses in molecular biology, instead of googling some very basic high-level articles and over-generalizing to support your misguided point.

You do understand that biology is complex and multifaceted, and aging/healing is more complex than "oxidative stress bad", right? The body does double/triple/n-tuple with almost every biomolecule. "Inflammation" (which isn't a single process) is widely vilified but it's absolutely necessary to grow and heal.

Valid. But so long as "periodic table of X" is a trope, I'm gonna complain about them.

I could have sworn there was a subreddit or something for "bad periodic tables", where someone has laid out a collection in a table-shaped way, without any mind to organization or patterns. But all I find now is "breaking bad" related stuff. Maybe it was a fever dream.

I agree that it's fairly arbitrary, but humans like order and structure and patterns. I think that's why the periodic table is captivating and magical.

Oof. Well I feel like an internet twat now :p However this is also one of my most heavily accoladed HN posts (in terms of imaginary internet points) so clearly this struck a chord with a lot of readers.

Clearly you are optimizing a different set of constraints and loss function. It seems like you value sticking closer to overall shape and count, as well as certain allegories between the tool and the element of that slot.

But on the other hand, like, why not solder at 82 (Lead)? Why not collets at 24 (Chromium) (a pun on CR collets and also collets are frequently high-chromium steel). Make room for oxy cutter / thermic lance on 8?

This is some god-tier nerd sniping, I love it.

> By all means rag on me for that choice too.

Actually I thought that was a great touch. Also I am pretty sure even-sized wrenches (hex in particular) is a reference to 6-member carbon rings, very appropriate.

> But then I ran out of heat-related tools that made the cut to be categories

You could fill halogens exclusively with welding processes. Odd/even wrenches are separate, why aren't AC and DC welding, or stick/mig/tig? Absolutely this is one of those "engineering/design decision" tarpits.

But...

BUT...

Really, when I think about what the periodic table means to me, I don't think about it in terms of shape, count, or location even. Really, I think about it in terms of valence electrons. My orgo teacher always said "The electron is where it's at". If I need a soft +2, I could grab Mg or Ca, sure, but maybe Cu2+ will do the trick. I can make soap (or something soap-like) with basically anything reasonably willing to shed those first two electrons. I can reach in my chemical toolbox for one of a collection of similar atoms to pull off a certain task, because of that lovely electronic geometric dance of electrons. And it just feels like the "shape" of each group going down the line is just not as consistent as my, admittedly very neurotic, neurospicy brain would like. And that's a me thing. Fundamentally, this is all my opinion.

> In conclusion, please keep the hate flowing and buy my poster and book.

You definitely earned a purchase for me :) I was already eyeing it but your rebuttal definitely sealed the deal.

I'm sure you put countless hours of effort and emotion and decision into your table and I don't mean to detract from the art of it (and let this be a lesson to the audience of the perils of feeling pseudonymous on the internet). I really appreciate the work. But boy howdy does it nerd-snipe me!

Similarly, I can hit a concert A3 (220Hz) pretty reliably from a cold start, +/-50 cents at worse, and that's just as a lifelong music dabbler. But also I was on depakote for a few months almost two decades ago (no intensive musical training in that time, it's kind of ass for mental clarity). I notice I start to lose my reference whenever I try one of those pitch trainer apps. But I've just started messing around with this pitch practice so I'll see how it goes.

Obviously. It'd be one of the tables known to Harvard. Just leave enough room for the ones to be discovered.

Obviously everyone has their own classification. But TFA doesn't even distinct cutters from air pressure tools. I'd at least make a group for Fluid Workers: air compressor, water pump, hydraulic ram, hydraulic press.

As a former chemist and all-around maker, I love this and this bugs me all at once. I love the concept, but as others have pointed out, this is less a "periodic table" and more "grab bag of related things". You see these all over the place: foods, drinks, cars, etc. All table, no periodicity. Why are wrenches and drills strewn across three groups? Put the wrenches in one group, drills in the other. Impact drivers somewhere in between.

There's some vague grouping, but it's pretty hodge podge.

The way I would do it, is use electronegativity (tendency to give or remove electrons) as a proxy for additive/subtractive. Atomic weight is a proxy for actual weight/scale. Group I would be like clay forming (the OG additive process), concrete, FDM, SLS, injection molding, casting. Group II is a bit less additive, more bonding: hot glue, soldering, brazing, welding. Halogens hog out material: thermic lance, plasma cutter, laser, waterjet. Chalcogens: hand router, (power) router, lathe, mill.

Metrology doesn't add or subtract, so obviously that's your Noble group.

Transition metals are all the fasteners. Lanthanides/Actinides are all the weirdos. I'd also add a group for just the simple machines. I think it's more important to have groups, periodicity, and trends, than sticking to the exact shape/size of the periodic table of elements.

This is Theodore Gray too! Author of a bunch of books and posters on chemistry.

Well, you know what they say, if you want something done right...

I disagree it's "settled science". There's mild evidence depakote (valproate) re-opens the critical period and allows improved pitch learning. Personally I like to avoid betting against neuroplasticity. Historically that pans out to be a bad bet again and again.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3848041/

Drugs may not even be necessary.

https://news.ycombinator.com/item?id=18227794

https://www.biorxiv.org/content/10.1101/355933v1

Anecdata: https://www.reddit.com/r/perfectpitchgang/comments/or0sye/ad...

> Buy a treadmill

Have one. Plus chin up bar, and there's always bodyweight.

> and jog on it for 20 minutes when you wake up.

That's a routine.

> Whenever you remember to do it.

That's more akin to how my brain functions. But "when I remember" (/ have energy/motivation) is a huuge variable I struggle with.

I understand you mean well but this is a thing I've struggled with for years. It tends to be boom or bust. I can go months with going to the gym regularly and it helps, then things get chaotic and it all falls apart, and it's exceptionally hard to restart, probably because of exactly such an executive deficit such exercise would help with.

Exercise definitely helps my symptoms, but it's an absolute roll of the dice whether it's immediate and significant, or just tires me out. Really I need to keep up with a few times a week for at least a month to reap the benefits.

> Maximal effects were found for tasks related to executive functions, (i.e., aspects of higher cognition principally associated with the functions of prefrontal cortex).

Oh good, exactly what I'm looking for. If only the executive dysfunction didn't mess with my ability to form any kind of stable exercise routine.

I just tested this in firefox on ubuntu. Three subsequent new tab tests.

Load: 4.34s, 5.14, 2.96, 3.35

DOMContentLoaded: 3.65s, 4.56, 2.92, 3.33

Finish: 13.14s, 10.77, 8.49, 12.02

So it's getting a bit faster over time, but still heinous, and crucially, it isn't hanging on requests. Individual asset GET/POST requests are taking tens of ms, worst was a few parallel 254ms GETs on a cold start. Usually 50-70ms. But there is a flurry of requests, then a period of very few requests until 5s after init, then another flurry.

Firefox 119.0 Ubuntu 22.04 uBlock Origin, Privacy Badger

Same OS, chrome 115.0.5790.170, no blockers, youtube is much snappier, it still definitely takes a few seconds to paint thumbnails, but it's basically done by 5s. DOMContentloaded is never more than 1.75s, finish <8s.

Firefox private window with blockers off has similar time statistics. But actually doubleclick.net is still getting bounced.

There's a lot more context baked into an ISO string than a unix timestamp though. Write a regex to find all the strict ISO8601-RFC3339 strings in a directory. Now write one for unix timestamps.

> Also calculating amount of time between two ISO8601 strings without libraries is nor trivial, or any other operation actually.

That's true of any datetime that actual humans use (as opposed to computers, financial systems, sysadmins and programmers).

> a descriptive reason for why the value is nil.

Result<T,E> does this. I forget exactly why Result is actually different from, and in fact superior to, `func foo() (*T, error)` but IIRC it has to do with function composition and concrete vs generic types.

Except objectively they stated ahead of time that a success would be stage separation, everything else is gravy. I had this same argument on HN after IFT-1. Folks were trying to argue that it was a failure because it blew up before orbit, when Elon was saying the whole time that just getting off the pad would be a success.

What is the sudden change in the exhaust plume at occurs here [1] at 149km / 17650 kph? I believe that's squarely in the thermosphere, and there aren't any step changes in temperature/pressure at that point that I'm aware of. It would make sense if that were near the mesopause, but that's around 100km.

Maybe it's something on SpaceX's side of things, a change in the burn profile? Perhaps it's related to losing the Starship about a minute later.

[1] https://youtu.be/w9OsSN2kJrk?t=446

I'm sorry, what's that, something about failure? I can't hear you over the thunderous roar of cheers from the Spacex engineering team after stage separation.

https://youtu.be/w9OsSN2kJrk?si=FZ30c9jmkMOmYo3n&t=180

Certainly doesn't sound like the folks who built the thing thought it was a failure.

Watching the replay, it looks like some of the engines failed to light during boostback reignition. Then, either total flameout occurred, or AFTS started cutting fuel in preparation for termination (maybe there are settings for "terminate right tf now" and "try to shut down engines before popping off", idk just speculating).

Either way, it looks like the start of boostback was not quite norminal, and AFTS decided that wasn't close enough to the flight envelope and decided to exit status 1.

Some are speculating that the flip maneuver sloshed the fuel too much and resulted in vapor ingestion and/or complete fuel starvation. The fact the failures are clustered on the side the fuel would slosh away from adds weight to this idea.

https://youtu.be/081a5Thjl5g?si=JUT3P6EcnG51hmHI

Aren't director boards majoritarian? Isn't the whole point that the board has the power? A coup or power grab would be if the CEO managed to convince a minority of the board to work in the CEO's favor, to the detriment of the majority. I'm not even sure how that would work.

> But yes, I agree it’s not the right choice for me and many others who want to have full ownership over our data,

The whole point of Signal is you have full ownership of your data. You said you can transfer the data to another device, right? I get that inability to export cleanly is an annoying bug, but technically you have full control over your data the whole time. It seems to me that it's easier to guarantee no one else can get your data (at the expense of data export friction), than it is to provide "do anything you might want with your data" while still guaranteeing privacy.

> One of their jobs (like the invisible waiter at a high end restaurant that makes dirty utensils go away) is to "retrieve" anything that the astronauts "put down".

This is fascinating. I'm not quite following what is meant by retrieval though. I assume from context the divers aren't retrieving to return the tools to the astronaut, and rather are emulating the drift that occurs in a frictionless vacuum? "Oops I set it 'down' and now it's 200m away".

> Lost Wall

I presume this is a "Wall of Shame" of sorts?