Unfrozen Mystery: H2O Reveals A New Secret

Carnegie Institute For Science June 10 2013 (Thanks, Cliff)

A fragment of the crystal structure of the new ice is shown where the oxygen atoms are blue and the molecular hydrogen atoms pink.

Washington, D.C.—Using revolutionary new techniques, a team led by Carnegie’s Malcolm Guthrie has made a striking discovery about how ice behaves under pressure, changing ideas that date back almost 50 years. Their findings could alter our understanding of how the water molecule responds to conditions found deep within planets and could have implications for energy science. Their work is published in the Proceedings of the National Academy of Sciences.

When water freezes into ice, its molecules are bound together in a crystalline lattice held together by hydrogen bonds. Hydrogen bonds are highly versatile and, as a result, crystalline ice reveals a striking diversity of at least 16 different structures.

In all of these forms of ice, the simple H2O molecule is the universal building block. However, in 1964 it was predicted that, under sufficient pressure, the hydrogen bonds could strengthen to the point where they might actually break the water molecule apart. The possibility of directly observing a disassociated water molecule in ice has proven a fascinating lure for scientists and has driven extensive research for the last 50 years. In the mid-1990s several teams, including a Carnegie group, observed the transition using spectroscopic techniques. However, these techniques are indirect and could only reveal part of the picture.

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Researchers Link BPA To Reproductive Problems, Abnormal Egg Development

Natural Society | September 26 2012

A new animal study links bisphenol-A (BPA) exposure in females in utero with reproductive problems later in life, including abnormal egg development.

“All the eggs that a female is going to have in her lifetime are formed before birth,” says researcher Catherine VandeVoort of University of California, Davis. “Anything that disrupts that process is going to have an impact later in life.”

Impaired Follicles and Division

For the study (which will be published next week in the journal Proceedings of the National Academy of Sciences), scientists put fetal monkeys in two groups. A control group remained unexposed to BPA while another group was exposed to the chemical through daily food during second or third trimesters or through an implant that administered constant, low doses of BPA.

The eggs of fetuses exposed to BPA had difficulty forming follicles, which surround eggs during development. Being unprotected in this manner often leads to eggs dying before maturation, according to VandeVoort.

Other abnormalities seen in the eggs were signs that they would carry too many chromosomes from being unable to divide during development, leading to miscarriages or disorders like Down Syndrome.

Closest yet to Human Study, Effects

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