Cap'n Refsmmat

This one nails me fairly often. If your cursor isn't in the text box, backspace means "previous page", not "delete text", so clicking in the wrong place makes your browser eat your post. Even worse, on my laptop there's no Home key, so I try to press Cmd-Left to go to the beginning of the line. Nope, that's "Back" in the browser, but "Home" in every other application I use. So I'll be halfway through a post and whoops, now it's gone.

Where did you use it? In the files attached to post #3, you did your u-substitution incorrectly, which forced you to use integration by parts. You should not have to integrate by parts. Remember: if u=1/x, then du=1/x2dx. You need to account for this when you replace dx with du.

It is not true that if u=1/x, then [math]\int \frac{e^{1/x}}{x^2} \, dx = \int u^2 e^u \, du[/math] You need to figure out what du is in terms of dx.

I think so. There's actually a medical condition known as "fructose malabsorption," where people don't absorb fructose well into the walls of their intestines, so the osmosis effect goes the other way. It has unfortunate effects.

Maybe try u-substituting u = 1/x.

A tip: it's osmosis, not "osmos." If the fructose is absorbed into the cells of the small intestine, there's a high concentration of fructose in the cells and a lower concentration outside. On the other hand, there's lots of water outside the cells, lurking amongst the loose stools. In this case, what does osmosis suggest the water will do? Where will it go?

Some time ago, the makers of our forum software started working on an iOS app for it. Unfortunately they eventually abandoned the project. We might be able to set up Tapatalk, assuming I can get rid of the obnoxious pop-ups it makes.

Yes, members can't give negative reputation until they have 30 posts.

If the government uses incoming revenue to service the debt, will there be any money left over to pay Social Security, Medicare, soldiers' salaries, VA hospital costs, and so on? We don't have to default on our debt to cause a catastrophe.

Hold your horses. The Amber Alert system is still functioning -- it's run by local police departments, not the federal government, and they can still issue alerts. The informational website about the system is down, that's all. The current list of active Amber Alerts is not kept by the federal government, either: http://www.missingkids.com/Amber Hanlon's Razor would suggest that Michelle Obama's website is still up because it is run by a different federal agency whose bureaucrats have interpreted the rules differently. There's no single administration official running down a checklist of websites and deciding "no, screw the missing kids -- but keep Let's Move, that's important!"

Computer science degrees usually teach programming only incidentally. Programming is necessary to complete the courses, but learning ActionScript or C# is not the goal of the program. I am sure you can find many jobs that do not require a computer science degree, only programming experience. You will be limited, though. Computer science (things like algorithms, data structures, parsing techniques, the low-level architecture of computers, and operating system design) provides many useful tools which can be used to solve complex problems. Take a look at the curriculum of a college computer science program and contrast it with what you're learning at home.

Try it now. I think I fixed it.

You might be interested in the famous paper "The Unreasonable Effectiveness of Mathematics in the Natural Sciences". I view mathematics as a rigorous but versatile language for expressing rules and relationships between things. When we encounter phenomena that cannot be expressed using mathematics, we invent new rules and new concepts to describe them. (Consider, for example, Newton and Leibniz inventing calculus and using it to express the laws of physics.) If the universe runs on rules, it's no surprise that we can describe it using a system like mathematics, just like anything else that runs on rules (at least approximately).

It works on forums that have specifically installed it. Usually it's used by scientists to write scientific papers, but since it's capable of typesetting mathematics we use it here on the forums. Many forums about science or math will have some form of LaTeX installed, but it's not guaranteed.

For gamma emitters (cesium-137, cobalt-60, strontium-90), your intestines will get a sizable dose of gamma radiation. I don't know if it would be enough to cause radiation poisoning or long-term effects. Alpha emitters (like polonium-210) will do Bad Things to you when ingested, because the alpha particles dump all their energy right into the intestinal lining. There's the extra problem of the chemical toxicity of the materials, which I know nothing about. The materials are generally embedded in the holder so they are very difficult to break free -- I haven't heard of that ever happening. However, if your dog were to eat an alpha source, I suspect he'd be in for a bad time. It's beyond my level of expertise to know how bad.

Small test sources like that are detectable maybe five or ten feet away. Beyond that it's very difficult to detect a small radioactive source. With a very sensitive detector (not your ordinary Geiger counter) I was unable to detect a small collection of test sources from about eight feet. Only large radioactive sources, such as industrial sources or patients treated with radioactive materials for medical reasons, can be detected from greater distances. I have also heard amusing stories about thyroid cancer patients (who are treated with radioactive iodine-131) flying from Russia to the United States without any trouble, only to be detected by a university police department whose officers carry radiation detectors. Apparently radiation is not part of the usual airline security checks. (But don't bet on it.) As for safety, kits like the one doG linked to are regularly given to undergraduates to play with in labs. I've had them in my pocket. The only safety issue would be if you ate a few.

Sorry guys. The hamster running the server is demanding 15-minute union coffee breaks and health benefits. I've entered extended negotiations but haven't made any progress yet.

Server load graphs are showing that it's running more smoothly today than it has been running for a couple weeks. I hope that means I fixed it. (It's still taking over a second to make each page, which is very slow, but at least tolerable.)

I installed Microsoft Security Essentials on my parents' computers a while ago and promptly forgot about it. No nagging about updates and no slowness. But then, previously I had used Norton, which makes anything look good in comparison.

I think dave has ICMP firewalled off, so there are no ping replies. Possibly. We're probably being assaulted for our shameless defense of Einsteinian relativistic orthodoxy.

I'm still seeing pageloads taking four or more seconds instead of four-tenths of a second, so I'll keep looking. Something is hammering MySQL pretty hard.

dave and I are supposed to have server responsibilities but neither of us has much time lately. dave made some changes to the MySQL configuration recently, thinking he could tune its memory use. I keep records of every change made to the configuration, so I reverted the changes to see if that makes things better. According to the counter at the bottom of each page, the site is currently taking five to ten seconds just to render a thread; that's clearly unacceptable, and I think MySQL has been choking. Hope this works.

That's how you start a blog here, if you want a blog at blogs.scienceforums.net. But you can get a blog anywhere you want, really.

I have not. I'll look into it later.

I've just tried to fix the blank page problem. Please let me know if it recurs. The blogs may still be slow -- our server is struggling under the load it sees every day -- but I think they'll at least load. I'll try to think of speed improvements if there are any to be had. I also just disabled Firestats, because it's keeping a record of every hit to the blogs and taking massive amounts of time to load in the admin panel. And then tinkered with MySQL, breaking the site for a bit in the process. Let me know how it goes.