Uncategorized
- Math
Sequence Puzzles
Given a sequence consisting of the whole numbers 1, 4, 9, 16, 25, 36, and 49, what number comes next in the sequence? The most likely answer is 64–the next number in a sequence of squares of consecutive integers, starting with 1. Such sequence puzzles are a staple of textbook exercises, brainteaser collections, and various […]
- Math
Coins for Making Change Efficiently
The item I had just bought cost 29 cents. I gave the cashier a dollar bill, and she gave me two quarters, two dimes, and a penny in change. She could just as well have given me seven dimes and a penny or some other combination of coins adding up to 71 cents, but there’s […]
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19320
This article could have been a little less disingenuous. It would still have been a very good article if you had used “sulfuric acid” instead of “odorless hydrogen sulfate” and admitted that the process still required a little alkali to neutralize this waste stream that is “carried away by water trickling over the foam.” Jim […]
- Tech
A Breath of Fresh Air: Bacteria rid sewage of its stink
Wastewater-treatment plants can use hydrogen sulfide-degrading bacteria instead of chemicals to reduce odors.
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Harvesting Intelligence: IQ gains may reach rural Kenya’s kids
Researchers say they've uncovered a dramatic IQ increase among Kenyan children over a recent 14-year period that may be due to environmental factors such as better nutrition and a greater parental emphasis on schooling.
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19319
Your article says, correctly, that our research group performed ultrasound of the main blood vessel of the women’s arms as a measure of vessel-cell function throughout the body. However, we identified women at risk of preeclampsia by performing ultrasound tests to assess blood-flow restriction of arteries in the uterus during the second trimester of pregnancy. […]
- Health & Medicine
Preeclampsia Progress: Blood test for predicting pregnancy problems
A natural compound called asymmetric dimethylarginine (ADMA) may play a role in preeclampsia, a pregnancy complication.
- Materials Science
Nanofluid Flow: Detergents may benefit from new insight
Fluids containing nanoscale particles spread and readily lift oil droplets off a surface.
- Paleontology
Winging South: Finally, a fly fossil from Antarctica
A tiny fossil collected about 500 kilometers from the South Pole indicates that Antarctica was once home to a type of fly that scientists long thought had never inhabited the now-icy, almost insectfree continent.
- Earth
Farm Harm: Ag chemicals may cause prostate cancer
On-the-job exposure to certain agricultural chemicals may be responsible for farmers' high rates of prostate cancer.
- Astronomy
Starry View: Image reveals galaxy’s violent past
The most detailed visible-light picture ever taken of the heavens reveals that the nearby Andromeda galaxy has had a much more violent history than our own Milky Way has.
- Anthropology
Ancestral split in Africa, China
Environmental conditions may have encouraged Homo erectus to develop a level of social and tool-making complexity in Africa that the same species did not achieve in China.
