Marne (river)The Marne (maʁn) is a river in France, an eastern tributary of the Seine in the area east and southeast of Paris. It is long. The river gave its name to the departments of Haute-Marne, Marne, Seine-et-Marne, and Val-de-Marne. The Marne starts in the Langres plateau, runs generally north then bends west between Saint-Dizier and Châlons-en-Champagne, joining the Seine at Charenton just upstream from Paris. Its main tributaries are the Rognon, the Blaise, the Saulx, the Ourcq, the Petit Morin and the Grand Morin.
Sébastien Le Prestre de VaubanSébastien Le Prestre de Vauban, Seigneur de Vauban, later Marquis de Vauban (baptised 15 May 1633 - 30 March 1707), commonly referred to as Vauban (vobɑ̃), was a French military engineer and Marshal of France who worked under Louis XIV. He is generally considered the greatest engineer of his time, and one of the most important in European military history. His principles for fortifications were widely used for nearly 100 years, while aspects of his offensive tactics remained in use until the mid-twentieth century.
ParisParis (ˈpærɪs; paʁi) is the capital and most populous city of France, with an official estimated population of 2,102,650 residents as of 1 January 2023 in an area of more than , making it the fourth-most populated city in the European Union as well as the 30th most densely populated city in the world in 2022. Since the 17th century, Paris has been one of the world's major centres of finance, diplomacy, commerce, culture, fashion, gastronomy and many areas.
Hypoxia (medical)Hypoxia is a condition in which the body or a region of the body is deprived of adequate oxygen supply at the tissue level. Hypoxia may be classified as either generalized, affecting the whole body, or local, affecting a region of the body. Although hypoxia is often a pathological condition, variations in arterial oxygen concentrations can be part of the normal physiology, for example, during strenuous physical exercise.
Decompression sicknessDecompression sickness (abbreviated DCS; also called divers' disease, the bends, aerobullosis, and caisson disease) is a medical condition caused by dissolved gases emerging from solution as bubbles inside the body tissues during decompression. DCS most commonly occurs during or soon after a decompression ascent from underwater diving, but can also result from other causes of depressurisation, such as emerging from a caisson, decompression from saturation, flying in an unpressurised aircraft at high altitude, and extravehicular activity from spacecraft.
Uncontrolled decompressionAn uncontrolled decompression is an undesired drop in the pressure of a sealed system, such as a pressurised aircraft cabin or hyperbaric chamber, that typically results from human error, structural failure, or impact, causing the pressurised vessel to vent into its surroundings or fail to pressurize at all. Such decompression may be classed as explosive, rapid, or slow: Explosive decompression (ED) is violent and too fast for air to escape safely from the lungs and other air-filled cavities in the body such as the sinuses and eustachian tubes, typically resulting in severe to fatal barotrauma.
