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Comment: Re:danger vs taste (Score 1) 475

by Rei (#49565631) Attached to: Pepsi To Stop Using Aspartame

Having a strict target is not impossible, and when the difference between consumption and expenditure is on the order of 500 calories, you have room for error on both ends - on your estimation of your consumption and on the estimation of your burn.

There was a rousing ITV, or BBC, I don't remember, documentary on a woman

Whoa - throw away all of the scientific data, there's an anecdote here involving an TV show about an uncontrolled experiment whose data we can't see and whose name you can't even remember!

The human body works on calories. The human digestive system does not throw away energy from digestible substances. It's energy in vs. energy out.

Comment: Re:My summary on systemd (Score 1) 404

by jbolden (#49564783) Attached to: Debian 8 Jessie Released

How can a service handle a situation when it is down? The services have to register in advance how to handle things. Moreover other services might still have issues.

  B depends on C and C needs to reinitiate with B, but D is also talking to C. How does the new B signal C?

As for it being contrived that's one of the key issues in process management how to handle chains and stacks of processes. That doesn't happen much in the sysv world because sysv handles it so badly that everything ended up having to write its own process manager.

Comment: Re:With the best will in the world... (Score 1) 369

by Rei (#49564703) Attached to: Audi Creates "Fuel of the Future" Using Just Carbon Dioxide and Water

Of that, its 1.4 litre turbo-charged diesel engine weighs about 90kg.

The engine, of course, being only part of the drivetrain components that can be eliminated by a switch to electric drive. Transmission, radiator, all fluids, fuel, the whole exhaust system, etc. In some designs you can even replace the driveshaft. You basically gut 90% of the moving parts.

The fuel tank holds about 42 litres of diesel weighing... whatever that weighs.

About 30 kilos.

It can do 600 miles urban or ~700 miles motorway, driving normally.

And that spec is relevant why? No seriously, please tell me. In what sort of realistic scenario is it critical to be able to drive for 700 miles nonstop without ever setting foot out of your car? How can you even do that? Do you not pee? Do you not eat? Even if you could it's not safe to drive that long nonstop, a person is supposed to take regular rest breaks. You stop for lunch, you plug your car into a fast charger, and you go off on your way afterwards.

The reason gas and diesel cars have such huge tanks has nothing at all to do with that being some sort of remotely practical requirement. It's to minimize a great inconvenience of ICE vehicles, that is, how often you have to go out of your way in your daily life at regular intervals in whatever weather it is and stand outside pumping fuel into your car. In your daily life, you never have to do this with EVs. Not once.

The longest range electric car that I can actually touch right now is the Tesla Model S; It's 3 times the size of my car, weighs over twice as much and has a third of the mileage, and costs 10x as much.

Really, we're going to compare a brand new luxury sports sedan with a used family car? That's the comparison we're going for? Have you tried comparing your car with a Bugatti Veyron?

Comment: Re:With the best will in the world... (Score 1) 369

by Rei (#49564607) Attached to: Audi Creates "Fuel of the Future" Using Just Carbon Dioxide and Water

Slow down there. You're comparing the complete-cycle efficiency for petroleum to just the end-stage efficiency for electric.

You seem to have not noticed what this article is about. It's about making fuel from electricity and then giving it to cars. Both sides start with the same feedstock: electricity. So it doesn't matter how efficient the electricity was to make because it affects both paths equally.

But let's switch back to your "scenario that I want to talk about that's not the one in the article"

Slow down there. You're comparing the complete-cycle efficiency for petroleum to just the end-stage efficiency for electric. That electricity needs to be made somehow. Toss in 40% efficiency for coal plants (we'll leave out pumping/mining and fuel transport costs for now, assuming they're similar for oil and coal), battery charging efficiency of about 75% [futurepundit.com] (discharge efficiency is unspecified, but since the EPA mileage estimates are based on battery capacity it's safe to ignore it), and the 85% motor efficiency you've specified, and suddenly your EV is .4*.75*.85 = 25.5% efficient. Same as a diesel.

I don't see that figure in your link, and I don't really need your link because I'm familiar with the numbers already. It depends on what you mean by "charging efficiency". The US grid averages about 8% distribution losses, plant to breaker. Li-ions are over 99% efficient at slow charging, but depending on the type can drop a few percent in faster charging scenarios, and in an extreme situation down to the lower 90%s. The charger itself has some losses, if I recall correctly from the breaker they're usually 92-94% efficient. So a good middle of the road number is more like 84%.

Also note that EVs automatically also function as hybrids: they regen and don't "idle".

Their EV is cheaper to operate not because the EV is more energy-efficient, but because coal is so much cheaper than gasoline

Coal is of course the dirtiest widely used power source, and its usage is declining in most first-world countries. Natural gas and wind have the highest growth rates. The most efficient combined cycle natural gas plants are upwards of 60% efficient, although that's not an "average" efficiency, but even old plants are generally over 40%. Efficiencies on things like wind, solar, etc are of course not particularly meaningful, since you're not burning a fuel. Nuclear has a low efficiency, but again, that's not particularly meaningful.

Even putting solar panels on your roof and amortizing the costs in most climates makes running an EV cheaper than gasoline. It's not because coal is somehow ridiculously cheap. It's because oil is a really expensive energy source per joule.

Wind is only about twice the costs of coal

If this was true, people would be churning out new coal plants, not wind farms.

Comment: Re:danger vs taste (Score 1) 475

by Rei (#49564477) Attached to: Pepsi To Stop Using Aspartame

No, it doesn't break down in the stomach. It breaks down in the small intestine. Very, very rapidly, leaving no detectable levels in the blood,.

The most recent study I read was in 2008 or so (and yes, I read the entire thing)

You read one study among the hundreds on one of the most highly studied food additives in history? Great, let me know when you're done with the others. ;) And I'm sure there was zero selection bias in your choice of which of the many studies to read ;)

Wikipedia covers the "cancer" thing well enough for a primer:

Reviews have found no association between aspartame and cancer. These reviews have looked at numerous carcinogenicity studies in animals, epidemiologic studies in humans, as well as in vitro genotoxicity studies. These studies have found no significant evidence that aspartame causes cancer in animals, damages the genome, or causes cancer in humans at doses currently used.[8][38][41] This position is supported by multiple regulatory agencies like the FDA[58] and EFSA as well as scientific bodies such as the National Cancer Institute.[47]

Concern about possible carcinogenic properties of aspartame was originally raised and popularized in the mainstream media by John Olney in the 1970s and again in 1996 by suggesting that aspartame may be related to brain tumors. Reviews have found that these concerns were flawed, due to reliance on the ecological fallacy[59] and the purported mechanism of causing tumors being unlikely to actually cause cancer. Independent agencies such as the FDA and National Cancer Institute have reanalyzed multiple studies based on these worries and found no association between aspartame and brain cancer.[41]

As discussed in the article on controversies around aspartame, the Cesare Maltoni Cancer Research Center of the European Ramazzini Foundation of Oncology and Environmental Sciences released several studies which claimed that aspartame can increase several malignancies in rodents, concluding that aspartame is a potential carcinogen at normal dietary doses.[60][61] The EFSA[62] and the FDA[58] discounted the study results due to lack of transparency and numerous flaws in the study, finding no reason to revise their previously established acceptable daily intake levels for aspartame.

Comment: Re:danger vs taste (Score 1) 475

by Rei (#49564405) Attached to: Pepsi To Stop Using Aspartame

This is a strange post.

1) How does this have anything to do with anything that I wrote?

2) How is this anything but agreeing with what I wrote, that it's the concentration of the methanol that matters? (note: it's a myth that only methanol causes hangovers; ethanol does also, although methanol is far worse per unit mass)

3) Methanol poisoning can be acute or chronic. A couple shots of spirits containing 10-20% methanol can cause serious optic nerve damage in one sitting. A few shots of pure methanol can kill you in one sitting.

And yes, I know how one distills liquer. :) While there's no exact rules, a general approach is to toss off anything that has a "chemical" smell (which doesn't come from methanol, but from acetone, which has a fairly similar boiling point to methanol, nearly as high), recycle anything that has a "fruity" smell (ethyl acetate, which has a boiling point very similar to ethanol and much higher than that of methanol), and keep only that which smells only like alcohol. Methanol of course also smells like alcohol but the lower boiling point leads it to get mainly tossed from the first cup.

There's also a home test one can do for methanol if you want to be really sure - you expose it to an oxidizer, such as potassium dichromate with sulfuric acid. Ethanol oxidizes to fruity-scented acetylaldehyde while methanol oxidizes to foul, pungent formaldehyde which is a very easy scent to detect even in small quantities. But that's really not necessary with proper distilling.

Comment: Re:danger vs taste (Score 1) 475

by Rei (#49564287) Attached to: Pepsi To Stop Using Aspartame

Here, you can prove me wrong right now in just a couple weeks. We'll work on the honor system! Maintain a strict calorie count every day for the next four weeks, and do a good estimate of your caloric burn by standard formulae. Consume say 500 calories less every day than you burn. Weigh yourself before and after on an accurate scale under the same conditions (clothing, time of day, etc) - perhaps the average of a couple days of weighings at the beginning and end. Come back and tell me the results. If you didn't lose weight, I'll take you at your word and post an apology. How does that sound?

You realize that this "experiment" has been done again and again and time again, right?

Comment: Re:danger vs taste (Score 1) 475

by Rei (#49564269) Attached to: Pepsi To Stop Using Aspartame

" They have benefits for weight control because they help control appetite and delay hunger".

Funny, it's almost like I didn't write "Some routes may be easier to take than others, reducing cravings and the like."

getting a little regular exercise makes a huge impact on weight loss

Yes, that would be the "calories out" part of where I wrote "amount of calories in versus the amount of calories out".

It almost seems like you're having a debate with someone else.

Count your calories and estimate your calorie burn every day and make sure that you maintain a higher burn rate than consumption rate. And you will lose weight - it's really that simple. Yes, eating a lot of simple carbs and sugars will make you hungrier and sleepier - I never said it wouldn't. But that doesn't change how weight loss works. It's still "in" vs. "out".

Comment: Re:danger vs taste (Score 1) 475

by Rei (#49564225) Attached to: Pepsi To Stop Using Aspartame

Metabolism has been studied. It does not vary that greatly between individuals with the same activity levels. I seriously recommend that if you want to follow up your anecdote, you do actual calorie counts over a several week period between yourself and your roomate and keep track of walking distances and other forms of athletic activity. Then bring your actual data here and try to prove all of the science wrong with your two datapoints.

Comment: Re:danger vs taste (Score 1) 475

by Rei (#49564187) Attached to: Pepsi To Stop Using Aspartame

Your body cannot "make" you eat something. You have a brain. Different diets can cause different cravings and you may not have the willpower to override your cravings, but that's your own problem.

The facts are facts: weight loss is a matter of calories in vs. calories out, and you absolutely can lose weight eating twinkies. More to the point, this professor did it as a demonstration of this fact (he took a multivitamin, ate some celery, etc to make sure he got his essential nutrients, but the vast majority of his calories came from twinkies and other junkfood).

Comment: Re:Sucrose question (Score 1) 475

by ledow (#49563961) Attached to: Pepsi To Stop Using Aspartame

"Aspartame has been found to be safe for human consumption by more than ninety countries worldwide, with FDA officials describing aspartame as "one of the most thoroughly tested and studied food additives the agency has ever approved" and its safety as "clear cut""

So.... no. Probably not. But judging by the comments on here, you're not alone.

Have sugar. If you don't want sugar, but you want your drink to taste sweet, you can have natural sugars. Otherwise, you're fucked and eating synthetic stuff no matter what?

Almost all of those substances - in moderation - are food-safe and no more dangerous than eating sugar, or any other natural food. Some people might collapse and die from a single exposure, others it will make ill, others it will upset them a bit, but the vast majority will just eat it and get on with life.

If it worries you, go back to eating sugar.

Comment: Re: honey trap (Score 1) 51

The post office photographs and tracks every piece of mail. The other part of that equation hasn't been publicized yet - they have cameras with facial recognition software focused on all their mailboxes.

No, snailmail is not anonymous. It probably was anonymous around 2000. Almost definitely anonymous in 1990. Not any more!

Nothing succeeds like excess. -- Oscar Wilde

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