Uncategorized
- Health & Medicine
Enough Isn’t Enough: An epidemic of vitamin D deficiency
Many U.S. women of childbearing age, particularly those of African descent, lack sufficient vitamin D even though they consume the recommended amount.
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Regarding this article, as planes fly low over the bay to land at San Francisco airport, wing vortices frequently bend down and become twin waterspouts that last up to 20 seconds. Dave GrossmanPalo Alto, Calif.
- Humans
Dangerous Wake: Wing vortices yield a deadly secret
A new mathematical analysis of an aeronautical hazard known as wake turbulence could someday lead to improved air safety and increase the number of flights at major airports.
