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What is Rubella?

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Rubella Virus. Wikimedia Commons

Almost everyone is familiar with the measles and mumps, but the 'R' in the MMR vaccine might not ring a bell. Here's the lowdown.

Discovery and Symptoms

Rubella is a disease caused by a virus of the same name. It can be spread through the air or by close contact with a carrier and cause symptoms like fever, headache, runny nose, bruising, bloodshot eyes, muscle or joint pain and a fine, red rash, for which the disease is named.

Rubella was first described in the late 1700s by German physician Friedrich Hoffmann. Other Germans studied it and suggested that it was derivative of either measles or scarlet fever, and the disease was nicknamed "German measles," after the doctors who were most familiar with it. In 1814, another German doctor, George de Maton, was called to a school to investigate an outbreak of skin rashes. He recognized the symptoms of German measles and, while examining his patients, realized that the sickness was distinct enough from measles to be its own disease. In 1881, the German measles was recognized as an individual disease, and was named rubella (Latin for "reddish") by British Army surgeon Henry Veale in 1886.

Not So Harmless, After All

For a while, rubella didn't receive much attention. It was a relatively mild illness with symptoms that were uncomfortable but not life-threatening, and lasted only three days to a few weeks. Through the rest of the 19th century, it became a sort of rite of passage for kids not unlike, more recently, chicken pox. Almost every child got sick with it, and would just have to suffer the rash and aches for a few days. This changed in 1941 when ophthalmologist Norman Gregg noticed that a few years after a local rubella outbreak, he would always see a large number of children with cataracts, and often a few other congenital defects, too. Further research showed that, while rubella was not particularly hard on the children or adults who contracted it, the disease could be devastating to unborn babies if their pregnant mother came down with it. Babies with congenital rubella syndrome could be born blind, deaf, with heart defects or with developmental disabilities.

Rubella could not be ignored as harmless any longer, and doctors in the U.S. and Europe started looking for a preventative treatment. In 1964, the last major epidemic of rubella in the U.S. broke out. Some 20,000 infants were born with congenital defects after the disease struck them in utero, and another 11,000 died.  In 1969, Stanley Plotkin and colleagues from the Wistar Institute in Philadelphia developed a preventative rubella vaccine, which was then combined with the measles and mumps vaccines in 1972. After the vaccine's development, the number of rubella cases in the U.S. fell sharply, and today there are fewer than 1,000 cases reportedly annually. But Europe and Canada have not fared as well. In 2004, there was a rubella outbreak among an orthodox Protestant group in the Netherlands who had religious objections to vaccination; 387 cases of rubella were reported, and the disease then spread to Canada, resulting in 309 more cases there. Between the two countries, there were two fetal deaths and 14 babies born with congenital rubella syndrome.

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Big Questions
How Does Autopilot Work on an Airplane?
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How does autopilot work on an airplane?

Joe Shelton:

David Micklewhyte’s answer is a good one. There are essentially a few types of features that different autopilots have. Some autopilots only have some of these features, while the more powerful autopilots do it all.

  • Heading Hold: There’s a small indicator that the pilot can set on the desired heading and the airplane will fly that heading. This feature doesn’t take the need for wind correction to desired routing into account; that’s left to the pilot.
  • Heading and Navigation: In addition to holding a heading, this version will take an electronic navigation input (e.g. GPS or VOR) and will follow (fly) that navigation reference. It’s sort of like an automated car in that it follows the navigator’s input and the pilot monitors.
  • Altitude Hold: Again, in addition to the above, a desired altitude can be set and the aircraft will fly at that altitude. Some autopilots have the capability for the pilot to select a desired altitude and a climb or descent rate and the aircraft will automatically climb or descend to that altitude and then hold the altitude.
  • Instrument Approaches: Autopilots with this capability will fly preprogrammed instrument approaches to the point where the pilot either takes control and lands or has the autopilot execute a missed approach.

The autopilot is a powerful computer that takes input from either the pilot or a navigation device and essentially does what it is told to do. GPS navigators, for example, can have a full flight plan entered from departure to destination, and the autopilot will follow the navigator’s guidance.

These are the majority of the controls on the autopilot installed in my airplane:

HDG Knob = Heading knob (Used to set the desired heading)

AP = Autopilot (Pressing this turns the autopilot on)

FD = Flight Director (A form of navigational display that the pilot uses)

HDG = Heading (Tells the autopilot to fly the heading set by the Heading Knob)

NAV = Tells the autopilot to follow the input from the selected navigator

APR = Tells the autopilot to fly the chosen approach

ALT = Tells the autopilot to manage the altitude, controlled by the following:

VS = Vertical Speed (Tells the autopilot to climb or descend at the chosen rate)

Nose UP / Nose DN = Sets the climb/descent rate in feet per minute

FLC = Flight Level Change (An easy manual way to set the autopilot)

ALT Knob = Used to enter the desired altitude

This post originally appeared on Quora. Click here to view.

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Big Questions
What's the Difference Between Vanilla and French Vanilla Ice Cream?
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While you’re browsing the ice cream aisle, you may find yourself wondering, “What’s so French about French vanilla?” The name may sound a little fancier than just plain ol’ “vanilla,” but it has nothing to do with the origin of the vanilla itself. (Vanilla is a tropical plant that grows near the equator.)

The difference comes down to eggs, as The Kitchn explains. You may have already noticed that French vanilla ice cream tends to have a slightly yellow coloring, while plain vanilla ice cream is more white. That’s because the base of French vanilla ice cream has egg yolks added to it.

The eggs give French vanilla ice cream both a smoother consistency and that subtle yellow color. The taste is a little richer and a little more complex than a regular vanilla, which is made with just milk and cream and is sometimes called “Philadelphia-style vanilla” ice cream.

In an interview with NPR’s All Things Considered in 2010—when Baskin-Robbins decided to eliminate French Vanilla from its ice cream lineup—ice cream industry consultant Bruce Tharp noted that French vanilla ice cream may date back to at least colonial times, when Thomas Jefferson and George Washington both used ice cream recipes that included egg yolks.

Jefferson likely acquired his taste for ice cream during the time he spent in France, and served it to his White House guests several times. His family’s ice cream recipe—which calls for six egg yolks per quart of cream—seems to have originated with his French butler.

But everyone already knew to trust the French with their dairy products, right?

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