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mpreda

437 karma · joined September 22, 2016

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mpreda··on Tesla shares 48V architecture with other automakers
High current (amperage) requiring thicker wires, or more wires, thicker/heavier connections, more expensive switches, more cooling etc.
mpreda··on Tesla shares 48V architecture with other automakers
Could I have 48V for my GPU power supply as well, please?
mpreda··on COP28: Countries launch declaration to triple nuclear energy by 2050
According to official statistics [1], in 2022 Germany produced 33% of its electricy from coal (up from 30% coal in 2021). Of this coal, one third is brown coal. Judging from these numbers, the situation in Germany is a catastrophy from an ecological standpoint. Any german green that acted agains nuclear in Germany should feel deeply ashamed for what was achieved in the country. A green catastrophy in a country that could have been a leader! A national shame, I say.

[1] https://www.destatis.de/EN/Press/Graphics/Energy/2023/_Inter...

mpreda··on An Invasive Tick That Can Clone Itself Is Spreading Across the U.S.
Guineafowl : https://en.wikipedia.org/wiki/Guineafowl
mpreda··on A homeless man built a life underground Hampstead Heath (2020)
> but do it with professional builders, better tools and materials

Maybe a couple of professional builders could train and supervise the future owners, who'd do the building themselves (and learn new skills in the process). This would cut the cost down a lot more.

mpreda··on Nicotine (2016)
And the funny follow-up: after this one-time rather completly unpleasant experience, I developed an intense smell sensibility to nicotine that lasted about one month: I could feel/smell the presence of small amounts of nicotine and have a very somatic "sick" reaction to it. I guess my body learned quickly to alert me of the "poison". Luckily, this reaction dissapeared and everything reverted to normal after about one month.
mpreda··on Nicotine (2016)
I'm a non smoker, I never smoked. Once I decided to try a nicotine chewing gum, took one pillow and chewed it thoroughly. After about 5-10minutes I suffered some very very severe effects, including: I started sweating extremelly such that all my clothes become wet quickly and sweat was dripping down my nose, ears, and into my eyes. I felt an intense and urgent need to urinate and defecate, which luckily I could do on the spot (happened to be in the proximity of a public toilet). I think after about 30minutes the simptoms subsided. I subjectivelly imagined that I ran the risk of a heart attack there.

So, I'd like to warn any non-smoker that may want to try out nicotine: please start with a very small dose, and only gradually build up; because otherwise it can be dangerous.

mpreda··on SARS-CoV-2 Infection Affects Energy Stores in the Body, Causing Organ Failure
> as neuronal cells are famous for being powered anaerobically using glucose and/or ketones

Neurons are not famous for being powered anaerobically; if anything, they're famous for being powered exclusivelly-aerobic.

AFAIK, the neurons are dependent on oxygen, thus aerobic. And unless I'm wrong, the ketones for energy is also an aerobic process. The place where we normally find anaerobic metabolism is in muscles, which are able to produce ATP using glucose to lactic acid without oxygen.

mpreda··on SARS-CoV-2 Infection Affects Energy Stores in the Body, Causing Organ Failure
I guess "translational" refers to the relation between genes and proteins.
mpreda··on My Left Kidney
About erythropoietin (EPO), I understand it's a hormone whose amount is regulated by the need for oxygen in the blood (i.e. a feedback loop which regulates the amount of red blood cells to be just what is needed to satisfy the oxygen needs of the body).

So EPO is not limited by the ability of the kidneys to produce it (I expect, by a large margin). So one kidney would just as well be able to produce all the EPO you may need, the kidney is not the limiting factor.

mpreda··on Inhibition of fatty acid oxidation enables heart regeneration in adult mice
If this study applies to you, here's a life advice: avoid cats.
mpreda··on F-35 can’t be found after pilot ejected
Visually the cockpit of a fighter plane is located forward, thus very likely ahead of the plane's CG. Ejecting the pilot would thus move the CG towards the back of the plane, which is a less stable configuration making it more difficult to recover from a stall.
mpreda··on Show HN: Every Breath You Take – Heart Rate Variability Training
> inspiration increases intrathoracic pressure which triggers the CV control mechanism to think BP is higher via the baroreflex and therefore lower HR

It seems CRC raises HR during inspiration.

From https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4052709/ "The increase in HR during inspiration is referred to as respiratory sinus arrhythmia (RSA) and the increase in BP as Traube–Hering waves."

mpreda··on Bacteria generate electricity from wastewater
Yes, and that might help the reaction. Also heating the tank to the optimum temperature (for the particular bacteria) helps, optimum pH, etc. helps. But the point is to provide the "help" with electricity directly.
mpreda··on Bacteria generate electricity from wastewater
I think researching in the opposite direction has more potential. Let me explain:

what we want isn't to generate electricity through bacteria that digests wastewater -- what we want is to feed electricity to the bacteria that digests wastewater, just to enable that bacteria to do it better, faster, and "wider".

Let's imagine I have a septic tank behind the house. I don't need to find out how I can run a LED light from the bacteria in the tank. What I want is to plug that biosystem to electrical power, so that the septic tank biorection is 100x speeded up, in a 10x smaller tank. Even if it uses up a few Watts of power.

And, once we do that, think of the possibilities that open up: once you feed power into the biosystem, it becomes energetically possible to drive bioreactions in the opposite direction from the energy gradient, basically driving the reaction "up the hill" with electrical power. Now that's something!

mpreda··on NASA says distant exoplanet could have rare water ocean, possible hint of life
If we detected their planet, and they're significantly more advanced than us, then it follows that they know a lot about our planet already.
mpreda··on NASA says distant exoplanet could have rare water ocean, possible hint of life
Because it's directional communication (point-to-point), in order to be energy-efficient over long range.
mpreda··on NASA says distant exoplanet could have rare water ocean, possible hint of life
We do have animal rights, don't we?
mpreda··on NASA says distant exoplanet could have rare water ocean, possible hint of life
We can expect these posibilities: 1. no life 2. simple life 3. advanced intelligent civilization

In the first two cases, we need to send a physical probe there. In the third case it might be enough, and much faster, to send communication signals there and get answers back. The third case is also arguably the most interesting.

mpreda··on The Federal Helium reserve is for sale
> and 800 million cubic feet of helium

I don't understand why you'd measure the amount of a gas in volume units (e.g. cubic feet) given that any gas is "elastic" in volume, i.e. can take pretty much any volume depending on the pressure.

mpreda··on AMD Open-Source GPU Kernel Driver Above 5M Lines, Entire Linux Kernel at 34.8M
Pre-generated by AMD and committed, I assume.

If they were generated as part of the build, they would not be counted as SLOC (not being "source").

mpreda··on HMB supplement to stave off dementia [in mice]
HMB (beta-hydroxy-beta-methlybutyrate) is a supplement that might have an effect on Alzheimer's disease.

I was surprised to find this news article as I've been taking HMB (to help with muscle mass) for about a year now; so I can anecdotally answer some questions about HMB.

https://en.wikipedia.org/wiki/%CE%92-Hydroxy_%CE%B2-methylbu...

mpreda··on Why Nvidia Keeps Winning
OpenCL works. Give me anything that works, and I can wrap around it if I don't like the interface it provides, and still use it because it works.
mpreda··on Why Nvidia Keeps Winning
And who has access to MI300 and MI250 GPUs? I would program for them, but I can't ever get one, or anyone I know can.

How much does one MI300 cost, BTW? Is there a price published? are they available to buy anywhere?

mpreda··on Why Nvidia Keeps Winning
I use GPUs for FP64 (64-bit floating point) compute, and the best AMD GPU right now is still Radeon VII, which was released in 2019. Since then AMD split the GPU business into two lines, CDNA and RDNA, the point being to be able to charge much higher prices for the GPUs that provide good compute (i.e. CDNA).

The RDNA line is targeted at gamers. The reasoning apparently being "let's be careful that these RDNA GPUs are bad enough so they can't really be used for anything else but games; if the user is into compute, they should pay the big money for CDNA GPUs".

This is also reflected into the ROCm situation. ROCm has good support for CDNA GPUs, which is the hardware that is deployed in the huge national-lab GPU projects, where money is not an issue. The problem with that approach? normal people do not have access to CDNA GPUs that cost a multiple of 10000 USD apiece.

mpreda··on Banging sounds heard during Titan search, according to internal government memo
Indeed the pressure is huge down there, and this may represent a challange in inflating the ballon in the first place. Looking up the numbers, it seems the pressure at the Titanic is about 400bar, while the pressure of a CO2 cartdrige is about 800bar, so that works.

About the baloon becoming larger as it surfaces, a pressure release valve that vents the baloon based on the pressure differential with the exterior (water) may do the trick.

mpreda··on Banging sounds heard during Titan search, according to internal government memo
I wonder why the submersible was not equipped with redundant "self surface" systems. I imagine the overall density of this submersible to be close to that of water. Such that dropping some amount of ballast (like the metallic rails underneath) may lighten it enough to self-surface. In addition, some emergency "baloons" may be fitted, inflatable in an emergency by CO2 capsules to resurface. And an emergency system to open the sub (e.g. by blowing up a hole somewhere convenient) could be added as well to allow exit once at surface.
mpreda··on Emissions are no longer following the worst case scenario
> What can an individual do to not suffer?

Does "suffer" take into account "transitive suffering" from children? (from future generations, our offspring)

i.e. if I'm physically fine but my child is suffering, I suffer too.

Now, for what one can do, there are always two ways: one is, as suggested, to find a better spot for oneself and let the others go to hell for all I care. But what about the children?

other is to become millitant, and force action. Worse outcome for oneself, but potentially a better outcome for the children.

mpreda··on The world’s oldest ultramarathon runner is racing against death
Per run. Training for a 42km race, you have to train some endurance (put the length in).
mpreda··on Europeans drain billions from banks, fed up with shrinking savings
Would you share which Polish banks offer the 7%, 8%, 10%?
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