Take Two Pills and Don’t Call Me in the Morning
Up to 58 percent of physicians in the U.S. regularly prescribe placebos, according to a survey of 679 rheumatologists and general internists conducted by Jon C. Tilburt of the National Institutes of Health and his colleagues. Even though placebos may contain no active ingredients, many ailments still respond positively to them [see “The Placebo Effect,” by Walter A. Brown; Scientific American, January 1998].

Climate Control of Dynasties
In the late ninth century a disastrous harvest precipitated by drought brought famine to China, ultimately ending the three-century rule of the Tang Dynasty. Climate change may have been a cause, according to a stalagmite from northwestern China. Composed of calcium carbonate leached from dripping water, the stalagmite preserves a record of rainfall in this region. It shows that the vital rains of the Asian monsoon weakened at the time of the downfalls of the Tang, Yuan and Ming dynasties over the past 1,810 years. These times of strong and weak rains, when compared with Chinese historical records, coincide with periods of imperial turmoil or prosperity, as in the case of the expansion of the Northern Song Dynasty, when harvests were abundant. In the past 50 years, however, industrial soot and greenhouse gases are causing the rains to weaken. Perhaps that is why today’s rulers of China are eager to act on climate change. The stalagmite analysis appears in the November 7 Science. —David Biello

Sounds like Thunder
Conventional loudspeakers produce sound by vibrating back and forth, but new speakers made from sheets of carbon nanotubes create music the way lightning generates thunder. When an audio-frequency electric current was applied to stretchable, flexible transparent films of 10-nanometer-thick carbon nanotubes, physicists at the Tsinghua-Foxconn Nanotechnology Research Center in Beijing unexpectedly discovered they could make sounds as loud as commercial speakers. The scientists reason that the electrified nanotubes heat and expand the air near them, producing sound waves. These loudspeaker membranes can be stretched up to twice their original length without breaking and with little change to sound intensity. These sheets could be placed over paintings, windows, video screens—even in clothing, the researchers say, as a means to keep a person warm. They even put their handiwork—described online October 29 in Nano Letters—on a waving flag. —Charles Q. Choi

Seeing on Faith
Religion might literally influence how you view the world. Scientists in the Netherlands compared Dutch Calvinists with Dutch atheists, looking for any effects potentially imposed on thinking by the neo-Calvinist concept of sphere sovereignty, which emphasizes that each sector of society has its own responsibilities and authorities. The researchers hypothesize that Calvinists might therefore not be as good as atheists at seeing the big picture. Participants were shown images of large rectangles or squares that each consisted of smaller rectangles or squares. In some tests, volunteers had to quickly identify the shapes of the smaller parts; in others, the larger wholes. The Calvinists scored slightly but significantly lower than atheists did in correctly identifying whole images. The investigators plan to study other religions for similar influences. See more in the November 12 PLoS ONE. —Charles Q. Choi

X-Rays from Tape
Peeling adhesive tape can create nanosecond bursts of x-rays. The effect occurs when electrons from the stuck surface leap to the sticky side of the tape. They travel so fast that on impact with the adhesive side, they give off radiation. The x-rays appear only in near-vacuum conditions, however—air molecules slow down the electrons enough so that they produce just a faint glow. The discovery, which came to light in the October 23 Nature, could lead to inexpensive x-ray machines that do not require electricity. —Susannah F. Locke