Virus more powerful than a car

Relative to its size, a molecular motor used by viruses is twice as powerful as an automobile engine. That's why even very large viruses can self-assemble so rapidly.


Researchers used laser tweezers to measure forces generated by the nanoscale motor that packs DNA into a virus during the assembly of an infectious virus particle. This power allows the virus to reel in its long genome with remarkable speed.

“The genome is about 1,000 times longer than the diameter of the virus,” explained Douglas Smith, an assistant professor of physics at UCSD and co-author of the study. “It is the equivalent of reeling in and packing 100 yards of fishing line into a coffee cup, but the virus is able to package its DNA in under five minutes.”

The researchers say that their work could ultimately lead to better ways of designing antiviral medications. Drugs that target the DNA-packaging process could block the infection cycle by preventing viral assembly. Such drugs could also interfere with the ability of the virus to inject its DNA into the cells it infects because injection is facilitated by the high pressure at which the genetic material is packaged within the virus’ outer shell.

Where's the bathroom?

"¿Donde esta el baƱo?" "Ou sont les toilettes?" "Ein ahmer-hathe min fathe-lick?"

Some answers to that question can panic a traveler. Perhaps no answer is as disturbing as, "Bathroom? What bathroom?", particularly when delivered with a sweeping gesture toward an endless, featureless landscape.



The toilet habits of Americans are based, thanks to largely urban and suburban upbringing, on high expectations. Indeed, discussions about the relative advantages of one-ply or two, quilted or not, folded or bunched, can go on at length, in certain odd social circumstances, without second thought to the availability of toilet tissue, nevermind an appropriate place to use it.

In privyless generations an outhouse would have been a step up. Pioneers in covered wagons, no doubt, dreamed of a two-holer for the relative comfort afforded as protection from Nature's vagaries. Add pages torn from a Sears catalog and the next thing to luxury was at hand when compared to a few presumably carefully chosen leaves. In fact, toilet paper, per se, didn't appear on the scene until the mid-1800's when a 'thunder mug' under the bed represented real luxury and a commonplace alternative to late night forays outdoors.

But even today the intrepid traveler can be faced with daunting circumstances in search of the illusive excratorium and a wad of TP. In India, for example, you're more likely to find rolls of toilet paper on restaurant tables than in bathrooms, the better to wipe runny noses after spicy food. For that matter, just down your street and around the corner you'll find what are euphemistically referred to as 'sanitary' facilities that are anything but. Even a supposedly predictable restaurant chain's Buoys or Gulls room, with carefully initialed hourly inspection sheets, may leave you wishing you'd found another port in the storm. Modern airliners, with hundreds of engineering hours devoted to what amounts to little more than a high-flying teflon-coated outhouse, may challenge your standards, ingenuity, and athletic skill. And consider the gravity of the situation faced by an astronaut.

You'll be relieved to know, however, that in most other parts of the world people don't seem to worry about these issues as much as Americans. In many foreign countries 'down the street and around the corner' may be where you go...literally and figuratively, with no pretense at sanitary. Simply squatting by the road is considered perfectly modest and acceptable in many places. If they don't worry about it, you needn't either.

No one but American tourists seem to notice the al fresco facilities in Italy or street corner toilets in France, where see-under modesty panels are de rigeur. In Japan porcelain fixtures are a relatively new amenity, replacing a simple hole in the floor. Faced with such a novelty more than one undaunted Japanese lady daintily mounted the bowl facing the wall in a pose not unlike the youngster in the famous Norman Rockwell doctor's office scene.

Admittedly, other cultures apparently do consider hygienic issues, but with a more functional bent. Billy Wilder opined that France was the only country where the money falls apart and you can't tear the toilet tissue. And Americans are often bemused by the water fountain next to the toilet upon their first encounter with a European bidet. King George V proclaimed (from the throne?) that you should always go to the bathroom when you have a chance. In Morocco and parts of India, Africa, and Asia only the right hand is used for eating, ensuring that alimentation and elimination never go hand in hand.

In the end, American's abroad are advised to leave their bathroom habits behind, do what you have to do, and take a roll of paper with you--or at least a copy of this article. As one critic wrote, "I sit in the smallest room of the house. Your story is before me. It will soon be behind me."

A fitting end?

An appendix is a good thing

No not a book appendix, silly. The one in your belly. It's been dissed all these years—everyone says it's superfluous, has no function, tits on a boar, that kinda thing—but it's actually useful, it turns out. And not just the way Alfred Sherwood Romer and Thomas S. Parsons suggest in The Vertebrate Body (1986), p. 389: "Its major importance would appear to be financial support of the surgical profession.”

Docs at Duke University Medical School published a report this week that say it produces and protects good germs for your gut.



But it can kill ya. In fact, over 300,000 were hospitalized in the U.S. with appendicitis in 2005, and about 300 to 400 Americans die of appendicitis each year.

Remember, there are more bacteria cells than human cells in your body—10 to 1, actually. (Ewww.) But what happens if the bacteria in your intestines die or are, to use a delicate word, purged? Diseases such as cholera or amoebic dysentery clear your guts of useful bacteria (oh yeah, been there done that, from both ends). The appendix's job is to reboot your digestive system. Kinda like rebooting your computer from one of those keychain memory sticks.

Your appendix, it turns out, is a safe cul-de-sac for bacteria, located just below the normal one-way flow of food and germs in the large intestine. Today, if your gut bacteria die, it can usually be repopulated easily with germs they pick up from other people. (Wash your hands!) But before modern-day dense populations, and during regional cholera epidemics, it wasn't as easy to cultivate another batch of bacteria, so the appendix came in handy.

Interestingly, in less developed countries, where the appendix may be still useful, the rate of appendicitis is lower than in the U.S.. Prostate cancer is lower among people who, um, use that more too. Both may be examples of an overly hygienic society producing an over reaction by the body's immune system.

I wonder if eventually we'll find the same sort of thing about the tonsils?