That was probably LORAN-A, with which we used to share the 160m band (1.8-2.0 MHz). LORAN-C operates (or operated) in a dedicated allocation at 100 kHz. LORAN-A was shut down quite a few decades ago.

Actually, the US military has a very simple way of selectively shutting down GPS: they locally jam the L1 frequency. The satellites also transmit on a second frequency, L2, with an encrypted, high precision "P(Y)" code for which the keys are closely controlled. They have receivers that can work with just the P(Y)-code, so it doesn't matter to them if L1 is jammed.

This statement and the one in the summary assert that US cultural trends are inherent and immutable. Look at other countries that have different cultural norms and you will find that India has a booming female coding population. If US cultural norms make it so women do not feel comfortable entering fields is that the fault of women as your statement and the summary's seem to imply? In my opinion, as there is sufficient evidence that the situation in CS (and other fields) in the US is cultural not biological it is societies problem to change the cultural norms. The US will lose out on great ideas if the culture systematically inhibits women from entering the field.

The toxicity is actually an indirect effect. The fluorescent dyes can in their excited states react with molecular oxygen to produce reactive oxygen species that damage tissues. By reducing the time and energy of excitation of the fluorophores (by only exciting those actually about to be scanned by the microscope), this technique reduces the amount of toxic byproducts.

The one that drives me crazy is removing the ethernet port on MacBooks. Which wouldn't be too bad if Apple's USB or Thunderbird ethernet adapters lasted more than 6 months before breaking, but I'm on my 5th in slightly over 2 years now... finally bought a third party one in the hopes that it will be less frail.

No they clearly didn't care about stone tablet bearers.

Yeah, to have local governments build and maintain networks that serve all comers, commercial and private, while recovering all costs from usage-based user fees would be, dare I say it, socialism! Next thing you know, the socialists will even propose to have local governments build and maintain roads for the public good!

The problem is ITAR - International Traffic in Arms Regulations. The idea was to keep cheap civilian receivers from being used in ICBMs. For that reason, there's an altitude and velocity limit, but the language was ambiguous. Some manufacturers interpreted it as an altitude AND a velocity, others interpreted it as an OR. The latter create the problem.

Your explanation is pretty much correct. But getting higher with a balloon is literally exponentially more difficult because that's exactly how the density of the atmosphere decreases with height. Your balloon has to expand exponentially as it climbs, and exponentials are not functions to be trifled with. The vertical distance over which the atmospheric density decreases to 1/e of its starting value is the "scale height", and for the earth it is an average of 7.6 km (it varies with temperature). But you can see that just getting to 30 km (100,000') is already about 4 scale heights, with your balloon expanding by a factor of e^4. Even that much is harder than it looks because the balloon expands as rises, and the gas inside cools adiabatically, causing its density to increase. Even in thermal equilibrium with the air outside, that air is awfully cold, which doesn't help decrease the lifting gas density. I think 100 km is completely out of the question. That's the Karman line, and it was chosen as roughly the altitude where an airplane could not generate enough lift to hold itself up even if it was going at orbital velocity. That's not a lot of air.

Not quite. Assuming "100k" means "100 km", conventionally chosen as the edge of space, getting there going straight up from 30 km (an easy weather balloon altitude) requires an upward force greater than the weight of the payload. Anything less and you'll just fall back to earth. If you do this with a rocket (what else would you use?) you will find that doing it slowly is *very* expensive in propellant. In rocketry this is called "gravity loss", and it's one of the reasons rockets don't just go straight up to space even when the intent is to escape the earth. They fly an arched path known as a 'gravity turn': just enough altitude is gained to reduce air drag to an acceptable level while you try to build up horizontal velocity as fast as you can. The less time you spend with your rocket anything but horizontal, the lower your gravity losses will be and the more hard-earned rocket impulse you can devote to getting orbital velocity and *staying* in space.

Sorry, but the rules make no distinction between licensed and unlicensed spectrum. If you deliberately interfere with someone else's radio communications, you are breaking the rules.

Marriott's reply is laughable. It might work on unsophisticated readers but not anyone who knows anything about WiFi. They said they wanted to "protect" their guests against "rogue" access points. Well, if those "rogue" access points were spoofing Marriott's own SSID, they might have a point. But I certainly don't set my own portable hotspot SSID to that of any hotel. It's set to something quite unique, and it's encrypted. Nobody is going to mistake it for a hotel's network, much less actually associate with it.

Most artificial sweeteners sold in powder form contain a simple sugar or starch to add bulk and give the product free-flowing granules more similar to sugar. Since saccharin, sucralose, and aspartame all taste hundreds of times sweeter than sugar, they are used in much lower amounts, with bulk added for the consumer-serving preparations so that you don't have to add micrograms of sweetener to your coffee to get the equivalent sweetness of sugar. Either glucose (usually listed as dextrose) or maltodextrin are generally used, which is interesting since it means that sugar substitutes generally contain a small amount of carbohydrates. The little single-serving packets tend to have about 3 (kilo)calories each; in the US, the FDA allows foods with less than 5 calories to be labeled as "zero calorie," so they generally are.

I note that this study did happen to use all powder-form sweeteners (dissolved in water) which means that there would some small amount carbohydrate in the solution. That's a perfectly reasonable way to run this study, since these are widely used preparations of these sweeteners, but I do wonder if there might be a difference with a genuinely digestible-carbohydrate-free preparation.

That is a reasonable conclusion. That is not, however what the GP stated. The GP state the he wanted a text book written on anthropogenic climate change. That is very different than being able to explain it to a lay person that is being able to convince someone it is worth publishing. In the case of anthropogenic climate change the book would be rather short:

• * A number of gases interact with the upper atmosphere is such a way as to trap heat within the atmosphere.
• * Since the industrial revolution we have been releasing huge quantities of these gases that were previously sequestered within oil and gas deposits.
• * The churn of the atmosphere allows for the passage of the newly released gases from the lower atmosphere to the upper atmosphere.
• * Some of these same gases also sublimate into the ocean where they dramatically affect the PH of the ocean which cause major problems for the top dwellers of the ocean where much of our oxygen is generated.

The issue isn't that there isn't a text book or a clear laymen description of the problem it comes when someone says: so prove to me that the churn of the lower atmosphere can carry these gasses to the upper atmosphere and the scientist starts talking about climate models which cannot predict any specific event with a high degree of accuracy but do tend to predict trends with great accuracy. To me this is like saying: what is the energy of a particle in a chamber at a defined pressure, temperature and density. The answer is very easy to give the average but essentially impossible to give the exact unless your model knows ALL of the inputs (i.e. every momentum vector and quantum state of every atom contain within the chamber).

I am a physicist. I have explained the expansion of the universe to many lay people without trouble. I have also tried time and time again to explain it to my mother. All such explanations end with her asking "so where is it expanding into." The short answer to this is: nothing. And one can either accept that or learn metric differential geometry. The belief that whatever any given PhD is working on can "describe in laymen's terms what they are doing" does not mean a laymen has the knowledge to understand or even accept the details of the theory. Heck look at Quantum physics in the early 1900s and you see many very intelligent people thinking it is crazy because it is probabilistic. So in short a good scientist can explain to a laymen what they do but the laymen has to accept their expertise when it comes to many specifics.