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This is an interesting theory. But do Mexican soccer players do much better at home games?

Not clear what you are asking, but at the international level Azteca is notoriously advantageous…of course top European sides never visit so there’s no general empirical data.

And you won’t get much more from the world cup because the only ceded European side favored to play at Azteca is England in the round of 8.


>Think of the body like a car, suggests Clemence Blouet, a neuroendocrinologist at the University of Cambridge in the UK. You can drive fast, using lots of fuel and putting wear and tear on the auto. Or you can stick to a gentle 15 miles per hour, and the car lasts longer. Living in a high-protein or high-calorie fast lane, she muses, could lead to the accumulation of those pro-aging oxygen radicals. Protein, in particular, also turns on systems that promote growth as well as aging. Restricting the diet could mean fewer of those damaging radicals and less pro-aging actions, keeping the body in smoothly working order for longer.

The implications here for quality of life are pessimistic. Also, the "extension" in the study is about 10%, but driving responsibly can make your car last many times longer.


I think that fasting-mimicking diets are a way to potentially get some of these benefits through occasionally engaging these "slower speed" repair mechanisms without permanently living with bare minimum protein intake. But I also think that at this point so far we've seen fat, sugar, and then all carbohydrates villainized. I don't think that excessive protein is going to turn out to be a good idea either and it will likely also have its turn as villain, especially after all of these new high protein fad foods that are still highly processed junk run their course. People just need to balance their damn nutrients and eat whole foods. There aren't many real shortcuts to health, but we're just desperate to find them due to time poor societies obsessed with hyper-optimization.

Radicals, i think mostly caused by high carbohydrates, ie Advanced Glycation End Products (AGEs) which probably mainly are generated by overconsumotion of carbohydrates.

You can have a keto/carnivore diet which, will minimize AGEs, is the meat/protein actually bad for you? (Assuming you avoid the std diet carb overconsumption ofc)


So people are pushed to their limits at work, but a university neuroendocrinologist suggests living a relaxing life that would require blander diet. What a wonderful solution!

I guess I don't understand why this study is suddenly getting attention when these kinds of trials have been going on for years. This one doesn't seem to have a particularly strong methodology or particularly unusual findings. It's just another page in a very, very long record of evidence about vitamin D, and by no means settles any major controversy.

>I always thought that if separating water and salt were easy, our bodies would have evolved to do it so that we'd be able to drink sea water and be fine.

Unfortunately for terrestrial animals, it's just not that simple. Seawater contains a lot of microbial life, some of which can be infectious or toxic. Going to the coastline to drink is potentially hazardous, because it usually means descending a hill on a predictable route which will be attractive to predators. And you need to get pretty far into the water, usually, because of nasty stagnant runoff, which can come from decaying matter that washes ashore, and sand in the surf. That means you risk drowning. Plus, you don't just need the energy for desalination, but the infrastructure (similar problem to real life!), which means more and larger juxtamedullary nephrons in the kidney, which is already a major weak point on the back due to the high blood flow in the kidney. Meanwhile, most of your food contains a lot of water, especially if you're one of the 99.99999% of animal species that doesn't cook it.


They are talking about lithium recovery, but there is a less exotic byproduct I'm interested in. One tonne (≈ 1 m^3) of seawater contains about 1.3 kilograms of magnesium, equivalent to about 4 kg of magnesite ore. Typical desal prices are on the order of $1 per tonne. Magnesite ore goes for about $100 per tonne, so the crude magnesium in a tonne of seawater is worth about $0.40, which could account for a substantial fraction of the desalination cost. (These numbers are very rough.)

Now you ask: why don't we just recover magnesium from brines if it's so great? Magnesium recovery from seawater isn't that easy: typically you have to treat it with some kind of alkali (often Ca(OH)2), so the cost is dominated by the extraction process (your alkali is consumed!), and you're competing with a pretty cheap ore. But if you have a solid byproduct, instead of a liquid, the options for magnesium recovery might be a lot more efficient, potentially offsetting the cost.

The fourth-most-prevalent ion, sulfate, might also be interesting, at least in a hypothetical post-petroleum future where sulfur as a byproduct of fossil fuel extraction is no longer "free". Sulfate is also annoying to extract from seawater, but again if we have a solid, the rules change.

As for the "table" salt itself, I think we'd quickly saturate (!) the market.


Calcining Mg(OH)₂ -which is what you find in seawater - converts the soft compound into magnesium oxide, a valuable mineral commonly used in refractories, catalysts, and ceramics.The Chemical Equation: \(Mg(OH)_2 \xrightarrow{\Delta} MgO + H_2O\)Temperature Requirements: You need to heat the magnesium hydroxide to a temperature range between 500°C and 900°C. Heating at the lower end (around 500°C) yields a highly reactive, porous form of nano-MgO, while heating above 1,200°C creates "dead-burned" MgO used in high-heat industrial bricks.The Yield: The weight of your final MgO product will be roughly 69% of the original Mg(OH)₂ mass, as the evaporated water accounts for the 31% weight difference. Already energy intensive. To get to magnesium ore is another step.

>Calcining Mg(OH)₂ -which is what you find in seawater

I'm not sure what to say, because it looks like you are copy-pasting from Wikipedia or something like that. Anyway, Mg(OH)2 is not found in seawater. Mg2+ is found as a dissociated ion. When you dry it, it mostly becomes MgCl2 with a little MgSO4. Mg(OH)2 is produced from seawater by the alkaline extraction process I mentioned before, and the process in TFA is interesting because it might be better.

Also, nobody would ever make magnesite ore. I referenced magnesium ore prices to estimate the value of the magnesium-as-ore in sea salt, because using finished magnesium prices would be misleading. Magnesium is mostly consumed either as the metal or as the oxide in cements and ceramics.


> : \(Mg(OH)_2 \xrightarrow{\Delta} MgO + H_2O\)T

At least read what you're pasting


If you want to be really clever about it, maybe the ship is powered by the brine.

https://en.wikipedia.org/wiki/Osmotic_power


I like this! Though I’m not sure the math works. That page says ideal efficiency for that system would be something like 0.75 kWh/m^3. Compared to 4000 to 5000 kWh/m^3 of diesel. Now we don’t need to be efficient since the point is to use up our “fuel” and we don’t need to cary cargo for this to make sense but with numbers like that, I don’t think our boat will be able to make enough power to move at all.

Electricity costs make the headlines, but I have also heard that the datacenters apparently make a loud perpetual buzzing noise that is audible from a large distance. That sounds like reason enough to oppose one being built near me.

Data centre noise is a mix of low- and high-frequency intake and exhaust fan noise at the structure level, diesel or turbine generators for the centres supplementing their own power or running backups (sometimes with cooling towers), and no real investment in sound damping.

Combine them with the tendency to build them in open, flat rural areas that have few or no trees or other buildings to baffle the sound, then run them 24/7, and it becomes a chronic issue for people who live nearby (even miles away, if the acoustics are just right).

That shouldn't have been as much of a problem in the US as it's become, but data centre projects get built near where people live because the infrastructure is already there. That naturally raised it as an issue in the UK, where there's less unpopulated space, before data centres of that scale were built: https://www.telegraph.co.uk/business/2026/05/31/data-centre-...


Data centers behave as acoustic weapons: https://m.youtube.com/watch?v=_bP80DEAbuo


The article you linked doesn't do much to refute "data centres are acoustic weapons", just insists that symptoms are explainable by audible noise pollution. Sure, that makes it better?

It's simple. Noise based nuisances from datacenters fall in one of two categories:

A) don't exist, therefore not a concern

B) known to exist, therefore not a concern


Solar desalination looks pretty good in terms of efficiency. The problem is that the solar energy must now be collected at the shoreline. This means that a lot of coastal real estate gets turned into a desalination plant. Alternatively, you transport the water, but pumping seawater requires corrosion and fouling resistant materials throughout the system.

wouldnt something like UPVC/PVC/PEX not be good'nuff?

Two major contributing factors I can think of:

- land meats were all but banned in Japan for centuries prior to Perry's ultimatum, encouraging the development of alternatives in flavor and nutrition like natto and katsuobushi

- geographically, Japan had less access to land crops (even wheat was not common!) and more access to fish and seaweed than Korea


Here's my five minute lunchtime hypothesis: it's because the heart is on the left. As human behavior demanded increasing precision from the hands, being a little farther from the heartbeat was a slight advantage.


Here’s my multiple years of anatomy classes response: the heart isn’t on the left. The aorta is, sure, but the vena cava is on the right. Also people with situs inversus (essentially all organs flipped laterally from “normal”) aren’t obviously more prone to left-handedness.


I’ve wondered ever since fourth grade (where an anatomical model in a corner of the classroom always made it clear that the heart is centrally located) how the vernacular conception of the heart as located on the left originated and persisted.

Your post finally made it click for me – the aorta extending to the left gives the superficial impression of that being the heart’s location because it’s easier to feel the heartbeat through the skin, versus the more deeply embedded vena cava on the right.

Presumably this means, evolutionarily, greater vulnerability on the left, predisposing the left hand to shielding duties, leaving the right to more dexterous tasks like spearing. The cardiological hypothesis of right-handedness holds!


> Also people with situs inversus (essentially all organs flipped laterally from “normal”) aren’t obviously more prone to left-handedness.

I feel like this isn’t really an argument against the theory. If right handedness did evolve because of heart position, a later genetic mutation to have the heart on the opposite side wouldn’t suddenly undo the previous evolution towards right handedness.


Why are you assuming situs inversus, which occurs in species with no handedness (or, indeed, hands) came after handedness?

The argument is that the selection bias was towards precision and the hypothesis was that precision is influenced by heart position (which is, still, in the middle in humans)… individuals with situs inversus would be more precise in the left hand, thus if the causal hypothesis is correct AND the argument holds then there should be a selection bias that would result in a correlation between situs inversus presence and left-handedness.

In the end I don’t believe either the argument or the hypothesis hold even as much water as I can in either hand.


It might be hard to eliminate confounding factors depending on when the research was done. A lot of people in my generation were still dissuaded pretty heavily from writing with their left hands. I'm not entirely convinced anymore as a lay person that "handedness" is a real, distinct phenomenon that's primarily genetically determined or a result of the organization of the brain. It's equally possible that it's a learned preference and that the way the brain organizes around it is as a result of the preference's impact on how you have to solve problems with your preferred hand in a society that preferences right-handedness.


Not disagreeing that handedness is probably unrelated to heart position.

But why would situs inversus somehow be tied to this at all? If there's a gene that favors right-handedness, it's not like it would somehow "choose" left-handedness because the individual has their internal organs flipped.


Genes don’t favor (or not favor), but if a natural selection bias for precise dexterity exists AND heart lateral orientation affects dexterity precision THEN those with flipped lateral orientation should exhibit more dexterity in the left hand, thus they should be naturally selected for because of the same bias.

Now, I’d seriously doubt there’s any evidence whatsoever for the assumed selection bias in the first place, never mind any causal relationship between fine motor control and heart asymmetry, but the selection bias should apply to both flips of the anatomical mirror.


>Here’s my multiple years of anatomy classes response: the heart isn’t on the left.

Why is the left lung smaller, then?


The heart is asymmetrical, but it’s in roughly the center of the chest. The left auricle and ventricle are larger muscles because they’re pumping through the descending aorta to the extremities, that’s the systemic circulatory branch, the plumbing for which is also largely to the right, while the right are pumping into the lungs alone as part of the pulmonary circulatory branch. The left lung (right on those with situs inversus) has two lobes and basically accommodates the extra muscle mass on its side of the heart, but if you really want to kill someone you stab them through the sternum, kind of dead center, not where they hold their hand when performing patriotism.


>if you really want to kill someone you stab them through the sternum, kind of dead center, not where they hold their hand when performing patriotism.

Noted, thanks.


even this is wrong, a penetrating weapon aimed for the heart is applied below the sternum at roughly the positionof the 3rd shirt button, and thrust upward at shallow angle topass behind the manubrium, and is then levered into a pommel upward position so as to lacerate the heart


First, that’s because you want to keep your weapon, which implies you don’t really want to kill the killee. I’m assuming a half inch drill, and I’m leaving it powered up and spinning.

Second, note that what you don’t do when trying to hit the heart is aim left.


Well, yes, the point of the solid bone plate right in front of your heart is to block stabbings. And it works!

If you had a weapon that wasn't bothered by the presence of the sternum, and you wanted to stab the heart, you'd go right through the sternum.


the risk is one of being unable to extract the weapon expediently.

there is an unacceptable risk of having to abandon it.


Unless you're also trying to send a message where leaving the weapon is the message


such as, a sculpture or other improvisation perhaps even advertising material.

https://external-content.duckduckgo.com/iu/?u=https%3A%2F%2F... [JPG]


not only smaller but having 2 lobes rather than 3, the left lung is possessed of a featureknown as the cardiac "notch" an involution of the lobe that corresponds to the larger left ventricle of the heart.


More piping to and from the heart exists on the left instead of the right?


the Aorta and Vena Cava are muchmore central than sinistral.

the aortic arch begins decent left of the coronary corpus, but becomes centralized, tandem with the Vena Cava.


Wikipedia on Situs Inversus (visceral organs are mirrored, heart on the right, liver on left) [0], mentions mixed results regarding handedness. There would be a load of other confounding factors here and I know nothing about medicine.

0 - https://en.wikipedia.org/wiki/Situs_inversus


Situs inversus ("dextrocardia") is a rare disorder. What I postulated is a (very) small selective advantage leading to a neurological mechanism evolving over generations, not a direct line from the heart to handedness during development. Anyway, the effect would be very slight, and even if it did exist, it could have gone away later, but dexterity would have been baked in at that point (see also the ocular blind spot).


Childhood handedness development within the brain became independent of organ positioning, after positioning had become established.


That's a long time hypothesis of mine as well, but I think it stems from being stung or bitten by venom. If venom is injected into the bloodstream, it is desirable to be injected as far away from the heart as possible.

Some centimeters might not sound much, but over millions of years, the cumulative effect might be that 1% of human population every 10.000 years gets genetically optimized to hold their heart at a more protective spot.


Interesting!

Handedness is probably not (often) captured in healthcare records, but I'm wondering if epidemiologists could mine insurance claims (or some other data rich resource) to see if there's a correlation with serious outcomes (death, hospitalization, etc.) from venom and handedness.


That's a good idea, a very good idea actually, but I wonder about it's effectiveness due to a very small total number of snake bites nowadays, compared to the past.

Hundreds of thousands years in the past, hominids lived into much more tropical areas than today and there are a lot more spiders, scorpions, lizards and snakes in these warm places. It makes sense that insects and especially reptiles pushed the evolution of mammals in certain directions and the positioning of the heart in the human body might be one of them.

Today people live a much different lifestyle than having to deal with insects and reptiles all day long. I don't know if it is possible to decipher the past from today's data.


If this was the case wouldn't it be easier to measure the pulse in peoples left wrists? Which doesn't seem to be a thing?


But it is a thing. That's how it was always explained in school, among other places, when I was a kid.


There is also a bias for how babies are held [1]. It holds even with left-handers. Holding a baby's head near the mother's heart helps the baby get to sleep. Which means the baby doesn't cry (and attract predators) and also gives the parents more time to sleep at night.

It also allows right-handed mothers to do something with their dominant hand while cradling the baby in that position.

[1]: https://sites.psu.edu/clarep/2024/04/12/the-left-cradling-bi...


> Here's my five minute lunchtime hypothesis: it's because the heart is on the left.

Your hypothesis can't possibly be correct, because the only premise is false.


I wonder why you're getting downvoted? Even if it turns out you're completely wrong it's still an interesting point and something I never even considered before.


Sometimes I think people downvote me because they're frustrated that I didn't engage further. After twenty years of Internet discussions, I'm a little burned out and I tend to fire and forget.



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