Letters to the Editor

19273

There is a striking similarity in the wave patterns of the ash plume on the cover of the Sept. 13 issue (above) and those in the gas of the Perseus Cluster pictured in this article. Could it be that volcanoes produce sound waves we can’t hear but can see in the plume? Paul HeinsGainesville, Fla. […]

19272

I read this article with interest. Can you tell me what contributes to these deposits in arteries? Julie WinslettDahlonega, Ga. It’s not ingestion of calcium, at least in people with normal kidney function, says Paolo Raggi of Tulane University in New Orleans. Rather, the condition stems from damage to vessel walls wrought by high blood […]

19271

There is a striking similarity in the wave patterns of the ash plume on the cover of the Sept. 13 issue (above) and those in the gas of the Perseus Cluster (“A Low Note in Cosmos: Sounding out a new role for black holes,” SN: 9/13/03, p. 163: A Low Note in Cosmos: Sounding out […]

19340

The multiple-origin theory of ancient New World immigration reported in this article has a long and respectable scholarly history, though it’s tarnished from time to time by enthusiasts for one race or another. For an early popular treatment, see Men out of Asia by Harold Sterling Gladwin (1947, McGraw-Hill). Gladwin even mentioned the Pericú, who […]

19270

The idea of compensating tidal forces using a ring of compact matter isn’t quite “something no one has shown before.” A concept based on the same principles was analyzed 20 years ago by physicist Robert L. Forward, who published the details in a paper in Physical Review and his science-fiction novel Dragon’s Egg. Forward discussed […]

19339

This article suggests that the most likely transportation system of the sandstone across the continent would have been a river system. Could it have been due to tectonic movement instead? Edward B. FanUpper Marlboro, Md. Both Utah and the Appalachians are on the North American plate, so there’s no tectonic boundary between them. Sediments from […]

19269

This article on using magnetic fields to map and possibly treat brain disorders contrasted sharply with the article a few pages earlier about magnetic fields inducing cells to develop tumors (“Cells proliferate in magnetic fields,” SN: 9/23/00, p. 196: Available to subscribers at Cells profilerate in magnetic fields). I would strongly suggest that both the […]

19338

Medicine needs a new paradigm. The findings described in this article suggest something better than potentially important agents and a new class of drugs to reduce cancer risk, as observed by Barnett Zumoff. If you want to reduce your cancer risk, simply do what the Polish women mentioned in the story do: Eat more cabbage, […]

19268

Your cover article on using magnetic fields to map and possibly treat brain disorders (“Snap, crackle, and feel good?” SN: 9/23/00, p. 204: Snap, Crackle, and Feel Good?) contrasted sharply with this article a few pages earlier about magnetic fields inducing cells to develop tumors. I would strongly suggest that both the science community and […]

19038

In the article about infinity, the “stereoscopic” images of tiny squares on page 140 are too far apart to view in the conventional way. However, if the viewer holds the magazine at arm’s length and looks cross-eyed at the pair, the diagonal across the square becomes visible. Robin FrostSanta Barbara, Calif.

19337

Your article worries that hydrogen-fuel leakage may add to stratospheric ozone problems. Doesn’t that presuppose that the hydrogen for fuel is generated from a fossil source? What if the hydrogen is generated from air, seawater, or biomass? Clark WaiteDescanso, Calif. The source of the extra hydrogen molecules doesn’t matter, says geochemist John M. Eiler of […]

19336

This article notes tetrahydrocannabinol’s (THC’s) side effects of “sedation, giddiness, and paranoia” and then states that a new drug, AM1241, alleviates pain “without the side effects” of the marijuana ingredient. Yet the article also says there are concerns about AM1241 “undermining the immune system.” Marijuana has been shown to be an effective treatment for a […]