Cardiology

Current air pollution standards tied to higher heart risks

Long-term exposure to air pollution is tied to an increased risk of having a heart attack or dying from heart disease—with the greatest harms impacting under-resourced communities, new Kaiser Permanente research shows.

Health

Who benefits from vitamin D?

Studying the expression of genes that are dependent on vitamin D makes it possible to identify individuals who will benefit from vitamin D supplementation, shows a University of Eastern Finland study published recently in ...

Obstetrics & gynaecology

Novel misoprostol insert reduces labor time, need for oxytocin

(HealthDay)—Use of a 200-microgram misoprostol vaginal insert significantly reduces the time to vaginal delivery and the need for oxytocin, in women with an unfavorable cervix, compared to those using a dinoprostone vaginal ...

Health

BPA linked to obesity risk in puberty-age girls

Girls between 9 and 12 years of age with higher-than-average levels of bisphenol-A (BPA) in their urine had double the risk of being obese than girls with lower levels of BPA, according to a Kaiser Permanente study published ...

Health

Is lead poisoning behind some juvenile crime?

Lead is a common element but is found in old paints (including those once used on children's toys), soil, old piping, water, and the atmosphere from lead-containing vehicular fuels, even drinking vessels. At high dose it ...

Health

Vitamin D tied to women's cognitive performance

Two new studies appearing in the Journals of Gerontology Series A: Biological Sciences and Medical Sciences show that vitamin D may be a vital component for the cognitive health of women as they age.

Diseases, Conditions, Syndromes

New drug might help treat irritable bowel syndrome

(HealthDay)—A new drug significantly reduces the abdominal pain and constipation characteristic of certain types of irritable bowel syndrome, according to two new studies.

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Kilogram

The kilogram or kilogramme (SI symbol: kg), also known as the kilo, is the base unit of mass in the International System of Units and is defined as being equal to the mass of the International Prototype Kilogram (IPK), which is almost exactly equal to the mass of one liter of water. The avoirdupois (or international) pound, used in both the Imperial system and U.S. customary units, is defined as exactly 0.45359237 kg, making one kilogram approximately equal to 2.2046 avoirdupois pounds.

In everyday usage, the mass of an object given in kilograms is often referred to as its weight, which is the measure of the gravitational force—or heaviness—of an object. Weight given in kilograms is technically the non‑SI unit of measure known as the kilogram-force. The equivalent unit of force in the avoirdupois system of measurement is the pound-force. In strict scientific contexts, forces are typically measured with the SI unit newton.

The kilogram is the only SI base unit with an SI prefix as part of its name. It is also the only SI unit that is still directly defined by an artifact rather than a fundamental physical property that can be reproduced in different laboratories. Four of the seven base units in the SI system are defined relative to the kilogram so its stability is important.

The International Prototype Kilogram is kept in the custody of the International Bureau for Weights and Measures (BIPM) who hold it on behalf of the General Conference on Weights and Measures (CGPM). After the International Prototype Kilogram had been found to vary in mass over time, the International Committee for Weights and Measures (CIPM) recommended in 2005 that the kilogram be redefined in terms of a fundamental constant of nature. At its 24th meeting the General Conference on Weights and Measures (CGPM) agreed in principle that the kilogram should be redefined in terms of the Planck constant, but deferred a final decision until its next meeting, scheduled for 2014.

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