Uncategorized
- Health & Medicine
Little vessels react to magnetic switch
Magnets can act like vascular switches, increasing or decreasing blood flow to a region of the body.
- Earth
Traces of lead cause outsize harm
Minute amounts of lead in blood are worse for children than had been realized.
- Math
Recycling Topology
It’s hard to miss the triangle of three bent arrows that signifies recycling. It appears in newspapers and magazines and on bottles, envelopes, cardboard cartons, and other containers. The recycling symbol. Alternative (incorrect?) rendering of the recycling symbol. Cliff Long made a Möbius band the basis of his wood carving “Bug on a Band.” Photo […]
- Paleontology
Ancestors Go South
A group of new and previously excavated fossils in South Africa represents 4-million-year-old members of the human evolutionary family, according to an analysis of the sediment that covered the finds.
- Animals
Chicks open wide, ultraviolet mouths
The first analysis of what the mouths of begging birds look like in the ultraviolet spectrum reveals a dramatic display that birds can see but people can't.
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19315
The iron-sulfide hypothesis of life’s origin that Michael J. Russell and William Martin propose in this article is attractive because it provides an inorganic cell wall and a matrix with some catalytic capabilities. But even if the Russell-Martin hypothesis is true, it isn’t a comprehensive theory of bioorigins. The cardinal difficulty in the origin of […]
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A Rocky Start
A new origin-of-life theory holds that life began within the confines of iron sulfide rocks surrounding hydrothermal vents at the ocean bottom.
- Earth
Eye of the Tiger
Recent research has upended a 130-year-old, previously unchallenged theory about how the semiprecious stone called tiger's-eye is formed.
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19314
This article addresses how much energy is given up in the viscous processes of a thin sheet of turbulent fluid. The technique used to stir the soap film grabbed my attention. Is it possible that the electromagnetic emissions from the sun influence Earth’s winds in an analogous manner by acting on the naturally occurring ions […]
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19236
I have some questions regarding the statistics presented in this article. It states that up to 19 percent of women undergoing abortion experience regrets afterward. However, 50 percent of the women in the study have had multiple abortions. It seems reasonable to assume that these women would be far less likely to have regrets than […]
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19235
The first sentence in this article is incorrect when it refers to “a woman’s placenta.” A woman doesn’t have a placenta, nor does any other mammalian mother. The placenta is an organ of the fetus. The mother’s tissue ends at the uterus lining. Bruce S. SibbettSan Bernardino, Calif.
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Colossal Colon Tour
The Colossal Colon is a 40-foot-long, 4-foot-high replica of a human colon. Visitors can crawl through the colon or look through the viewing windows to see healthy colon tissue, colon disease, polyps, and various stages of colon cancer. Under the auspices of the Cancer Research and Prevention Foundation, the giant model will be on display […]
