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Comment Re:Bad math (Score 1) 212

There are 95 ASCII characters, which makes 95**8 = 6,634,204,312,890,625 possible 8 character passwords

Or you can use 6 random words from the oxford english dictionary, which gives you more combinations that the number of nanoseconds in the estimated lifetime of the universe, while still producing a passphrase that is feasible for a human being to remember.

Comment Re:Sure, but... (Score 1) 138

There are, certainly, some unambiguously 'strategic' weapons, of the 'bloody huge thermonuclear warhead on an ICBM'

Many of the ICBM's have selective yield, and even with the max yield they are not particularly powerful for nukes to be. The most powerful weapons are the ones dropped by aeroplanes, and they typically have megaton yields.

Comment Re:XKCD (Score 1) 487

My PRNG yielded:
74019,69542,70792,42388,32916,63978,55632

which maps to:
purchasing persecute platitudes escalations consummation mum intoned

Your pass-phrase is quite tricky to remember and type reliably. A better approach is to use different languages in order to increase the dictionary size. If you pick at random among the languages that use latin script, you can easily get a dictionary size above a million words. Just 4 such words would give a number of combinations exceeding 10^24. Even if you could try a thousand trillion combinations per second, it would still take in excess of thirty years to try them all.

Comment Re:False positives and false negatives ... (Score 1) 94

If you RTFA, for every 100 actual cases, it misses 7. That's 7 people who will think that they're HIV-free, and possibly spread it to others.

7% false negatives is a *terrible* number.

No it isn't. If everybody used this test, and the people who tested positive seek treatment, then you just reduced the transmission rate among the people who would not otherwise get tested by 93%.

I often run in to arguments like this when it comes to vaccinations as well. Many vaccines don't offer perfect protection. They just reduce the probability that a disease will spread in the population by a sufficient amount that you don't get major outbreaks, and thus the illness eventually dies out since it cannot spread effectively. More specifically, if new infections occur at a rate that is lower than the rate at which infected people are discovered and treated, the the total number of infections decrease. Since untreated HIV will eventually start showing symptoms, people will eventually get diagnosed, so the trick is to bring the overall infection rate down enough that you're more likely to be diagnosed and treated than you are to spread it to others.

Thus while highly preferable, it need not be perfect. If your measures to combat the illness cause a persistent decrease in the number of people infected, then the disease will eventually die out simply because it cannot spread.

As it happens that is also one of the reasons why you want everybody to have access to healthcare.

Comment Re:HIV transfer. (Score 2) 94

It's been found through studies of cases like yours that 'vanilla' couples sex, where the partners are otherwise healthy apart from one being HIV+ have well under a percent (.3% IIRC) rate per act of transmitting HIV.
For anal, this rises to 30%.

Your numbers are WAY off. The figures are closer to 0.1% and 1% respectively. See this study for details:
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1881672/?tool=pmcentrez

Other studies have been done for Gay couples and various groups, and the numbers come off similar. They may be off by a a small factor depending on exactly how the study was done, but that 30% figure you quote is nonsense.

Comment Re:Will it work? (Score 5, Informative) 141

Your way to do it probably had shitty efficiency. 1-2% of the electrical energy probably ended up used to produce hydrogen. With fancy catalysts and carefully controlled temperature, it's possible to improve that efficiency by a factor of 30 or so, with the best methods now getting efficiencies between 30 and 60%. The problem is that those schemes tend to either rely on very expensive catalysts (like platinum ), or they are chemical processes which produce CO2 as a by-product ( steam reforming, in which hydrocarbons are reacted with water to form hydrogen and CO2 ).

What the article seems to speak of is that they've found a catalyst that drastically improves the efficiency of electrolysis, without resorting to expensive materials.

Comment Re:Define "charges" (Score 1) 373

Better question is how many KWh can it deliver in 15 mins? Since vehicle battery capacities vary significantly, that's the relevant question.

Dunno about this particular technology, but the Japanese are standardising on a system that can deliver 60kW, with experimental designs up to 120kW.
In comparison, the Tesla's battery pack is about 50kWh, so the 120kW system should be able to charge it to 80% in 20 minutes.

 

Comment Re:Nutrition is imporant (Score 1) 487

It's possible to get everything you need from a strictly vegetarian diet - but it's very, very difficult.

No it's not. It really isn't. If what you say was true we would see vegans and vegetarians having poor health on average. In reality vegetarians have slightly better health than meat eaters in most studies, mostly because they're frequently the types of people who don't smoke and drink. When lifestyle habbits are taken into consideration the difference in health between vegetarians and meat eaters is slim to none.

Seriously, every now and then somebody comes up with som study to push the benefits of a particular diet. Vegetarian, HIgh carb, low carb, fish based, low GI, omega-3, but these always fail to live up to the very simpel scrutiny which shows that as long as you eat a varied diet, get the vitamins you need, and don't poison yourself with huge quantities of junkfood/drugs, you're going to be reasonably fine.

As for how to get all your vitamins and amino acids on a vegan diet. Vary your source of protein, take a B12 supplement, and eat 3 meals a day. You really don't have to worry much more than that.

Comment Re:Malnutrition (Score 1) 487

Even today, children of vegans still die occasionally due to malnutrition.

This is also true for children of meat eaters, yet you don't use that to argue against a omnivorous diet.

If we're going to actually listen to the professionals, multiple dietary associations from differentc ountries, and even the WHO themselves have made it very clear that Vegan diets are perfectly healthy. Yes, it means you need a B12 upplement, but before you use that as "evidence" that it's not a good diet, be aware that many food products are heavily fortified. Dairy products are often fortified with vitamin A and D. Salt often contains additional iodine. Drinking water is frequelntly fluorinated to help combat tooth decay. Many soft drinks use vitamins as acidity regulators or stabilizers. Cereals are frequently fortified with B vitamins and minerals ( Corn Flakes is a good example).

Despite of this you still see loads of people going "trololol, vegan diets are nto natural" conveniently forgetting that unless you grow your own food, your diet is very far from natural as it is. There is no evidence to suggest it is "better" to get your nutrition from meat, as long as you get what you need, and contrary to popular belief it is fairly easy to get everything from a vegan diet. Yes, you need a B12 supplement, but given that B12 is extremely cheap and safe, you can't really use that to argue it's a bad diet in light of how much of our food is fortified anyway.

Comment Re:Partially Blocked View (Score 1) 378

The scientific community was very sceptical to his claims until astronomical observations agreed with his predictions, making him world famous more or less over night. The same thing happened with global warming. People were sceptical, then the data started pouring in from various places, ranging from NASA to whether channels. The people who are sceptical now can best be compared to those who were still doubting Einstein's theory in 1940 because they didn't like the implications.

Comment Re:Because Hybrids Don't Pay For Themselves (Score 1) 998

But you can't fill up your massive battery in 5 minutes at any standard gas station.

This is true for the time being, but likely to change in the coming decades. There's newer forms o batteries that can recharge in 5-10 minutes, and several companies are designing electrical systems that can supply the necessary power. Now, these battery types are fairly new ( and hence expensive ), and it would probably take something like a government mandate to start retrofitting existing gas stations with the necessary electrical equipment, but technologically speaking it can be done.

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