Cardiology

Five threats to heart health you may not be aware of

Many people can recite the major risk factors for heart disease, the stuff of posters, public service ads and dire warnings: smoking, high blood pressure, obesity, diabetes, high cholesterol, lack of exercise.

Cardiology

Air pollution means pregnant women can't breathe easy

Pregnant women receive a lot of instructions to ensure the healthiest possible baby: what to eat and drink, what to avoid, which vitamins to take, which activities to avoid and more.

Health

Study finds link between hypertension and air pollution

A new study soon to appear in the Journal of Public Health suggests that air pollution and living in apartment buildings may be associated with an increased risk for dangerous conditions like heart disease, stroke, and type ...

Other

Frozen sperm retains its viability in outer space conditions

Zillionaires like Amazon founder Jeff Bezos who see the 'colonisation' of space as an answer to the Earth's ever threatened resources will be reassured to learn that human sperm retains its complete viability within the different ...

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Space

Space is the boundless, three-dimensional extent in which objects and events occur and have relative position and direction. Physical space is often conceived in three linear dimensions, although modern physicists usually consider it, with time, to be part of the boundless four-dimensional continuum known as spacetime. In mathematics spaces with different numbers of dimensions and with different underlying structures can be examined. The concept of space is considered to be of fundamental importance to an understanding of the universe although disagreement continues between philosophers over whether it is itself an entity, a relationship between entities, or part of a conceptual framework.

Many of the philosophical questions arose in the 17th century, during the early development of classical mechanics. In Isaac Newton's view, space was absolute - in the sense that it existed permanently and independently of whether there were any matter in the space. Other natural philosophers, notably Gottfried Leibniz, thought instead that space was a collection of relations between objects, given by their distance and direction from one another. In the 18th century, Immanuel Kant described space and time as elements of a systematic framework which humans use to structure their experience.

In the 19th and 20th centuries mathematicians began to examine non-Euclidean geometries, in which space can be said to be curved, rather than flat. According to Albert Einstein's theory of general relativity, space around gravitational fields deviates from Euclidean space. Experimental tests of general relativity have confirmed that non-Euclidean space provides a better model for explaining the existing laws of mechanics and optics.

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