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Comment Some estimates (Score 5, Interesting) 25

As is too often the case, the article is paywalled, and crucial information allowing for real understanding is hidden.

But, based on info given, some back-of-the-napkin calculations can be done. These are done with the intent to estimate doses, and thereby answer questions brought up in some of the comments here.

One obvious detail is that this will be intravenous infusion, something that can be started in the field with emt's and paramedics, or expeditiously in the ER.

Basics - CO poisoning is common, from vehicle and marine exhaust, faulty lamps-furnaces-camping equipment, faulty home heating, house fires, et al. Normally, hemoglobin (hgb) shuttles oxygen around. Hemoglobin is protein red blood cells, each hemoglobin protein carrying four heme groups each holding one iron atom. That iron atom wants to "rust" and bind with oxygen. Oxygen is picked up by hgb as blood goes through the lungs. In the periphery where O2 is needed, local chemistry based on CO2 and acid-base levels allow hgb to release the oxygen. It is one of nature's brilliant systems, and key is that Hgb can easily bind and unbind.

But, CO has very high affinity for hemoglobin, and once iron bound, it blocks oxygen binding. Once locked in, it does not dislodge, so the body loses that oxygen carrying capacity. All red cells eventually die and are replaced, so the situation is self correcting for low levels of carboxyhemoglobin, as you might have after sitting around a campfire or commonly in smokers. Generally, up to 10% carboxyhemoglobin is tolerated with no or minimum symptoms. On the other hand, 50% carboxyhemoglobin (instead of hemoglobin or oxyhemoglobin) is highly toxic and needs icu care, often fatal, and 70% COHg is uniformly fatal. Anything that can dislodge CO and thereby bring current red cells back "on line" is the goal.

Current best rx is oxygen, hyperbaric oxygen, and blood replacement in more extreme case, but these all take time to implement. This new RcoM peptide sounds promising for very rapid effects, in minutes.

Now, here is the estimated stoichiometry:
There is published info about RcoM which is a peptide with about 250 residues (amino acids), and this paper intro implies they modified the natural protein, presumably making a smaller peptide having the same CO binding affinity.

Each red cell has about 250 million hgb molecules, meaning 1 billion iron atoms = 10^9.
Red blood cell (rbc) counts in normal healthy people are about 5 million cells per cubic mm = 5 x 10^6.
A liter has one million cubic mm per liter = 10^6.
Normal adult blood volume is about 5 liters.

So : (10^9 iron atoms per rbc) x (5 x 10^6 rbc / cu.mm) x (10^6 cu.mm / liter) x (5 liters)
= 25 x 10^21 = 2.5 x 10^22, round off to 10^22 iron atoms per circulating blood (other rbc's are sequestered in bone marrow and spleen, but we can ignore for this calculation).

Avogadro's number is about 6 x 10^23. Rounding off :
(10^22 iron atoms / blood volume) / (10^23 atoms / mole) = 10^-1 moles/ blood volume.

In CO poisoning, each iron binds on CO, so there is 1:1 molar equivalency.

What I can infer from the article stub is that the RcoM peptide they made has high and tight CO binding, and once joined, the complex is excreted by the kidneys. It also sounds like one peptide of RcoM binds one molecule CO, so the molar stoichiometry is 1:1.
That means that 0.1 moles of their RcoM-HBD is need to suck up 0.1 moles of CO. That would be needed in a patient who has 100% carboxyhemoglobin, but they would be dead already, so we are talking about 0.05 moles for someone with 50% COHg.

Next question is - how many grams is 1 mole of RcoM-HBD?

The kidney is a giant filter. Pressurized blood in renal capillaries (going through a structure called the glomerulus) is filtered through a membrane into the urine space. Small molecules are forced across the membrane - water, electrolytes (inorganics), and small organics. The downstream renal tubules reabsorb the water and ash as they cannot otherwise be conserved (new such molecules must come from diet). Small organics are mainly waste that needed to be eliminated, or some small bioactive chemicals that the body easily regenerates. The healthy kidney has such a fine mesh "sieve" that larger molecules like proteins cannot pass through. Proteinuria is a key marker of renal disease as the membrane gets too porous. However, some peptides, too small to be officially classified as proteins, can get through. What is the limit on size of chemicals that normally get through the sieve or are blocked?

Peptides 10-12 kDa (kilodaltons, molecular weight units) filter freely. Proteins 50-70 kDA are blocked. In between, filtration drops off according to some curve. It is safe to assume from the paper that RcoM-HBD, freely and easily eliminated in the urine, is down there around 10-12 kDa.

How many residues (individual chained AA amino acids) are in a peptide weighing 10,000 - 12,000 daltons?
Average amino acid weight is about 110 da. So, (11,000 DA per RcoM-HBD) / (110 Da per AA) = 100 aa's.

Native RcoM has about 250 residues, so RcoM-HBD / RcoM = 100 / 250 = 0.4 which is also the relative molecular weight.
That number is not needed for further calculations, but it implies that these guys re-engineered RcoM to eliminate 60% of its weight, and that sounds quite plausible trying to derive a pharmaceutical from a natural source.

So -
In a patient with 50% COHg, we need 0.05 moles of therapeutic RcoM-HBD.
Molar weight is the molecular weight in grams, so if RcoM-HBD has molar weight 11,000, then
(11,000 gm / mole) x (0.05 moles) = 550 GM.

And - believe it or not, that is a reasonable number.

An analogous drug (in terms of bulk biological chemistry) is mannitol, a 6-carbon polyol (a sugar alcohol, basically a sugar molecule that stays straight instead of chasing its tail into a ring). It is a vital drug for treating brain edema, pulmonary edema, renal failure, trauma resuscitation, etc. Depending on the clinical situation, it is given IV "push", or IV drip, or both, push then drip. Push doses are typically 25-100 Gm.

So, a drug like this could plausibly given as, let's say, 50 Gm at once, then a continuous drip until a total of 550 Gm is administered. A comparable dose, 50 Gm, maybe every 10-15 minutes, would see a full course of rx administered in 2-3 hours.
Depending on the pharmacokinetics and clinical pharmacy, which would have to be studied in detail for approval and clinical use, might reveal higher lower limits or tolerances, and actual care adjusted accordingly.

I can foresee something like this being combined with mannitol infusion perhaps, to augment renal blood flow and glomerular clearance (if the RcoM is not inherently osmotic, probably not at 11 kDA), plus short term 100% oxygen but only for 2-3 hours until CO is cleared enough.

This stuff is pretty brilliant, and important, and life saving. Many of these estimates might be right or wrong, and many of these details might already be worked out by them - but behind a paywall - you all know about that.
But this "Fermi problem" estimation comes up with clinically and biologically realistic numbers.

Comment Leave science fiction to real authors (Score 1) 58

There was a similar article on Slashdot about a week ago - not the same topic or news item, but similar in that someone with some bona fides as a scientist or engineer was making polyanna predictions about future tech or tech-based ways of life.

The two are similar because - it is all a big "so what?"
Whatever their credentials, they are not writing about real tech or its applications. They are just fantasizing about the future based on some theme peripherally connected to what they work on their day jobs.

In the case of this article, if Cosimo Bambi is a black hole expert, then his thoughts about astrophysics and black holes is to be respected and admired. But, being a star scientist doesn't make him a rocket scientist. Reading the comments so far on this article, I think nearly every Slashdot reader immediately recognized the fallacies in his fantasies. His expertise as a star researcher does not make him any more knowledgeable than anyone else on Slashdot about how to get to the stars.

Spewing fantasies about a subject you have only some minor familiarity with doesn't make you an expert or even entitled to have an opinion. BUT - that can be okay when done right. We have done it for hundreds of years. It is called "fiction", in this case "science fiction", and like any fiction and literature, it can be engaging, intriguing, inspiring. Who here on Slashdot doesn't love good science fiction stories or movies?

Popular and award winning authors have a gift - being able to express their fictional ideas in interesting and compelling ways. That is their strength. Also, all good science fiction has a similar foundation - it doesn't have to be real, and it may ask us to accept some odd premise from an alternate universe or physics, but within that framework, the story is plausible. And when a fictional but plausible story is told by a story telling genius who wraps the fiction around a good plot and characters, the result can be magical.

In this case, Cosimo is not an engaging and beguiling science fiction story teller, just a science guy making a ridiculous prediction on a subject outside his expertise, based on nothing scientifically plausible. It's not just bad science fiction, it's stupid "science fiction". So, why does he get air time or page ink? Because he knows about stars? He gave a bad and inarticulate interview to a non-Pulitzer reporter on a slow news day. That's the real story. Nothing to see here - move along ...

Comment Re:NO INTERNET SERVICES for 35 years (Score 3, Informative) 75

I enjoyed your remarks.
You are exactly right, and so was gavron that you responded to.
You two obviously experienced those years first hand, and so did I. Remarks in this thread make me wonder how many of the commenters did not, and are measuring an older era with modern yardsticks.

Back then, those dial-up services were the only means of online or "e-community" access for nearly everyone who was not a computer whiz.
In the early 90's, most people did not have a home computer. For those that did, online connections were not standard. You had to buy and install a modem or internal card. You had to dial up to a local BBS or to CompuServe, and then AOL and similar wannabes.
Unless you were in CS or something techy at a university, you had no clue about the "internet".

In the early 90's, "democratizing" things that opened up computers to ordinary non-tech people were things like the 386 processor and its mate Windows 3.1 which exposed many ordinary non-tech people, via their computers at work, to using a computer on user-friendlier terms; and, AOL and it mass-marketing, which exposed users to connectivity with other users. AOL was not as sophisticated or rich with information as CompuServe, as I recall, but CompuServe never matured, then took a dump when bought by H&R Block (if I recall correctly), whereas AOL had the vision to expand and become the everyman service. The Time-Warner merger seemed to kill it because it was then unable to respond to evolving technology, but no one can discount its influence in those years circa 1995 - 2000.

What some comments in this thread seem to miss is that before there was an internet, there was dial-up. That was the best tech of the times. For those who learned to connect, it was with phone, modem, and CompuServe or AOL.
When Netscape and the World Wide Web came along, that was another revolutionary and democratizing event, a user friendly and widely marketed form of usenet-gopher-archie-ftp-etc., and later of Mosaic, none of which were everyman user-friendly and easy-to-access. They opened up the internet to ordinary people, and in turn spurred the need for high speed access which ultimately trivialized slow speed dial-up.

But, for users circa 1985-1990 to 1995-2000, dial-up to BBS, CompuServe, AOL, Genie was the only option - that was the standard technology. The internet and Netscape (then IE, etc.) were the newfangled technologies. Remember, once you are comfortable with a certain set of tools and workflow, newer and better technologies can take time to adopt or switch over or incorporate into your hearts and business. New users with no prior experience or allegiances are more likely to readily adopt the new technologies. People who grew up from the start with cable-dsl-broadband, Netscape-IE-Firefox, etc., www versus usenet, etc., they are now in their 20's and 30's.

Some comments in this thread seem to reflect that perspective, which is fair. But back then, as many of us remember so well, those modems and dial-up services, including AOL, for all its deficiencies as seen from a modern perspective, were revolutionary and glamorous. Horses and buggies would be glamorous to bare-footed troglodytes, and gas lamps and lamp lighters would seem thoroughly modern to candle dippers. You can't judge older technologies by today's standards. For those years back in the 90's, AOL, using the available tech of the times, and a technology people already had in their homes, the telephone, was a potent force to get people familiar with computers and connectivity. By building a market and money, it spurred the need and means for better faster tech - and here we are today.

Comment Stupid on evil (Score 1) 269

Microsoft, like most anyone making money off of computers these days, wants you on a subscription model that requires you to constantly send telemetry to their servers so they can rape your privacy for profit. They don't want you buying and using a product until something better comes out, they want that sweet recurring monthly income. It's evil.

Stupid, however, is expecting a company to sell you a product and then support it forever for free. The only reason Microsoft has to support Windows 10 past what they advertise as its lifetime is to prevent their product from becoming a PR embarrassment and impairing their ability to sell more software. Doing that for too long means lots of extra expense with no additional profit, and that's how businesses fail.

TL;DR - MS evil, lawsuit stupid.

Comment I'm generally anti-AI but... (Score 1) 97

Modeling has always been about some idealized image that doesn't represent real people in any reasonable way. They start with exceptionally attractive people and then use makeup, lighting, and lens effects to make them look even better. And when that's not enough, in more recent times they've been using Photoshop.

The human model has been holding the artists back from the completely artificial image they've always been pursuing.

Comment Buy nothing requiring direct Internet access (Score 4, Informative) 81

If it has to check in with a company's servers to function, they WILL either cease support or come after your wallet at some point.

Go with Home Assistant for control and devices that don't need to be connected to the Internet to work. Z-Wave, Zigbee and 433MHz are the things you should look for first before falling back to WiFi devices.

Comment Catch - 0001 0110 (Score 1) 41

One example shared in the patch shows a simple fix to a typo in the kernel's OPP documentation. Claude, an AI assistant, corrects "dont" to "don't" ...

The error wasn't in the kernel, not in the code, just in the documentation.
A simple spell check would have flagged or fixed that faster and with less carbon footprint.

So, AI not needed, just word processor or spell checker.
But, programmer is obviously ai himself, anti-intelligent, doesn't know how to use spell checker, doesn't even know he needs it.
So, ai needs AI. ...
AI not needed ... AI needed.

That's the high tech Catch-22.

Comment Two problems (Score 4, Insightful) 233

I don't believe the US currently has the capacity to make a laptop from scratch, even at 20% above Apple pricing. Assemble yes, but manufacture no. If it's possible at all, whatever corners are cut will ensure it's unusable as a computing device.

It's also far more likely this is some kind of investment scam than an actual legitimate business plan.

Comment Re:A 94% chance of getting hired (Score 1) 160

I'd like to see stats based on 100% of able-bodied, not-on-mat/pat leave, working-age, non-incarcerated people wanting to work, and then measuring the percentage of a standard work week per capita.

Total hours being worked divided by total available labour-hours.

Comment Re:WINNING (Score 1) 249

You think the Republicans, who now control everything including the Supreme Court, who can apparently run masked thugs around the country abducting people, denying them due process, and send them to concentration camps, will limit themselves to gerrymandering and a bit of light voter intimidation and maybe another seditious assault on the government if they lose?

The US is in for some highly corrupt elections, and anybody who complains about it is in for a world of hurt unless they're rich, white, and connected.

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