Cardiology

Researchers report clear shift in arterial diseases in diabetes

There has been a redistribution in the risk of arterial disease in type 1 and 2 diabetes. The risks of heart attack and stroke have decreased significantly, while complications in more peripheral vessels have increased in ...

Health

Miscarriages linked to health risks in later pregnancies

New Curtin University research published in eClinicalMedicine has revealed a link between miscarriage and the increased risk of developing complications of gestational diabetes and high blood pressure-related disorders in ...

Psychology & Psychiatry

For younger women, mental health now may predict heart health later

Younger women are generally thought to have a low risk of heart disease, but new research urges clinicians to revisit that assumption, especially for women who suffer from certain mental health conditions. A new study being ...

Health

Trial shows eggs may not be bad for your heart after all

Whether you like your eggs sunny-side up, hard boiled or scrambled, many hesitate to eat them amid concerns that eggs may raise cholesterol levels and be bad for heart health. However, results from a prospective, controlled ...

Health

High blood pressure hurts the kidneys

Hypertension, also known as high blood pressure, is a common problem that affects the body's arteries. If you have high blood pressure, the heart has to work harder to pump blood.

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High pressure

High pressure science and engineering is studying the effects of high pressure on materials and the design and construction of devices, such as a diamond anvil cell, which can create high pressure. By high pressure it is usually meant pressures of thousands (kilobars) or millions (megabars) of times atmospheric pressure (about 1 bar).

It was by applying high pressure as well as high temperature to carbon that man-made diamonds were first produced as well as many other interesting discoveries. Almost any material when subjected to high pressure will compact itself into a denser form, for example, quartz, also called silica or silicon dioxide will first adopt a denser form known as coesite, then upon application of more temperature, form stishovite. These two forms of silica were first discovered by high pressure experimenters, but then found in nature at the site of a meteor impact.

Chemical bonding is likely to change under high pressure, when the P*V term in the free energy becomes comparable to the energies of typical chemical bonds - i.e. at around 100 GPa. Among the most striking changes are metallization of oxygen at 96 GPa (rendering oxygen a superconductor), and transition of sodium from a nearly-free-electron metal to a transparent insulator at ~200 GPa. At ultimately high compression, however, all materials will metallize.[citation needed]

High pressure experimentation has led to the discovery of the types of minerals which are believed to exist in the deep mantle of the Earth, such as perovskite which is thought to make up half of the Earth's bulk, and post-perovskite, which occurs at the core-mantle boundary and explains many anomalies inferred for that region.[citation needed]

Pressure "landmarks": pressure exerted by a fingernail scratching is ~0.6 GPa, typical pressures reached by large-volume presses are up to 30-40 GPa, pressures that can be generated inside diamond anvil cells are ~320 GPa, pressure in the center of the Earth is 364 GPa, highest pressures ever achieved in a shock waves are over 100,000 GPa.[citation needed]

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