Early life and education.

Nimitz, a German Texan, was born the son of Anna Josephine (Henke) and Chester Bernhard Nimitz on February 24, 1885, in Fredericksburg, Texas, where his grandfather's hotel is now the Admiral Nimitz State Historic Site. His frail, rheumatic father had died six months earlier, on August 14, 1884. He was significantly influenced by his German-born paternal grandfather, Charles Henry Nimitz, a former seaman in the German Merchant Marine, who taught him, "the sea – like life itself – is a stern taskmaster. The best way to get along with either is to learn all you can, then do your best and don't worry – especially about things over which you have no control." His grandfather became a Texas Ranger in the Texas Mounted Volunteers in 1851. He then served as captain of the Gillespie Rifles Company in the Confederate States Army during the Civil War.  Originally, Nimitz applied to West Point in hopes of becoming an Army officer, but no appointments were available. His congressman, James L. Slayden, told him that he had one appointment available for the United States Naval Academy and that he would award it to the best qualified candidate. Nimitz felt that this was his only opportunity for further education and spent extra time studying to earn the appointment. He was appointed to the Naval Academy from Texas's 12th congressional district in 1901, and he graduated with distinction on January 30, 1905, seventh in a class of 114.

Military career.

Early career.

Nimitz joined the battleship at San Francisco, and cruised on her to the Far East. In September 1906, he was transferred to the cruiser ; on January 31, 1907, after the two years at sea as a warrant officer then required by law, he was commissioned as an ensign. Remaining on Asiatic Station in 1907, he successively served on the gunboat, destroyer, and cruiser.  The destroyer "Decatur" ran aground on a mud bank in the Philippines on July 7, 1908 while under the command of Ensign Nimitz. The ship was pulled free the next day, and Nimitz was court-martialed, found guilty of neglect of duty, and issued a letter of reprimand.  Nimitz returned to the United States on board USS "Ranger" when that vessel was converted to a school ship, and in January 1909, began instruction in the First Submarine Flotilla. In May of that year, he was given command of the flotilla, with additional duty in command of, later renamed "A-1". He was promoted directly from ensign to lieutenant in January 1910. He commanded (later renamed "C-5") when that submarine was commissioned on February 2, 1910, and on November 18, 1910 assumed command of (later renamed "D-1").  In the latter command, he had additional duty from October 10, 1911 as Commander 3rd Submarine Division Atlantic Torpedo Fleet. In November 1911, he was ordered to the Boston Navy Yard, to assist in fitting out and assumed command of that submarine, which had been renamed "E-1", at her commissioning on February 14, 1912. On the monitor "Tonopah" (then employed as a submarine tender) on March 20, 1912, he rescued Fireman Second Class W. J. Walsh from drowning, receiving a Silver Lifesaving Medal for his action.  After commanding the Atlantic Submarine Flotilla from May 1912 to March 1913, he supervised the building of diesel engines for the fleet oil tanker, under construction at the New London Ship and Engine Company, Groton, Connecticut.

World War I.

In the summer of 1913, Nimitz (who spoke German) studied engines at the diesel engine plants in Nuremberg, Germany, and Ghent, Belgium. Returning to the New York Navy Yard, he became executive and engineer officer of "Maumee" at her commissioning on October 23, 1916.  After the United States declared war on Germany in April 1917, Nimitz was Chief Engineer of "Maumee" while the vessel served as a refueling ship for the first squadron of U.S. Navy destroyers to cross the Atlantic, to take part in the war. Under his supervision, "Maumee" conducted the first-ever underway refuelings. On August 10, 1917, Nimitz became aide to Rear Admiral Samuel S. Robison, Commander, Submarine Force, U.S. Atlantic Fleet ().  On February 6, 1918, Nimitz was appointed chief of staff and was awarded a Letter of Commendation for meritorious service as's chief of staff. On September 16, he reported to the office of the Chief of Naval Operations, and on October 25 was given additional duty as Senior Member, Board of Submarine Design.

Between the wars.

From May 1919 to June 1920, Nimitz served as executive officer of the battleship. He then commanded the cruiser with additional duty in command of Submarine Division 14, based at Pearl Harbor, Hawaii. Returning to the mainland in the summer of 1922, he studied at the Naval War College, Newport, Rhode Island.  In June 1923, he became aide and assistant chief of staff to the Commander, Battle Fleet, and later to the Commander In Chief, United States Fleet. In August 1926, he went to the University of California, Berkeley, to establish the Navy's first Naval Reserve Officer Training Corps unit.  Nimitz lost part of one finger in an accident with a diesel engine, saving the rest of it only when the machine jammed against his Annapolis ring.  In June 1929, he took command of Submarine Division 20. In June 1931, he assumed command of the destroyer tender and the destroyers out of commission at San Diego, California. In October 1933, he took command of the cruiser and deployed to the Far East, where in December, "Augusta" became the flagship of the Asiatic Fleet.  In April 1935, Nimitz returned home for three years as assistant chief of the Bureau of Navigation, before becoming commander, Cruiser Division 2, Battle Force. In September 1938 he took command of Battleship Division 1, Battle Force. On June 15, 1939, he was appointed chief of the Bureau of Navigation. During this time, Nimitz conducted experiments in the underway refueling of large ships which would prove a key element in the Navy's success in the war to come.  From 1940 to 1941, Nimitz served as President of the Army Navy Country Club, in Arlington, Virginia.

World War II.

Ten days after the attack on Pearl Harbor on December 7, 1941, Nimitz was selected by President Franklin D. Roosevelt to be commander-in-chief, United States Pacific Fleet (CINCPACFLT). He was promoted to the rank of admiral, effective December 31, 1941. Nimitz immediately departed Washington for Hawaii and took command in a ceremony on the top deck of the submarine. The change of command ceremony would normally have taken place aboard a battleship, but every battleship in Pearl Harbor had been either sunk or damaged during the attack. Assuming command at the most critical period of the war in the Pacific, Admiral Nimitz organized his forces to halt the Japanese advance, despite the shortage of ships, planes, and supplies. He had a significant advantage in that the United States had cracked the Japanese diplomatic naval code and had made progress on the naval code JN-25. The Japanese had kept radio silence before the attack on Pearl Harbor, but now events were moving so rapidly that they had to rely on coded radio messages that they did not realize were being read in Hawaii.  On March 24, 1942, the newly formed US-British Combined Chiefs of Staff issued a directive designating the Pacific theater an area of American strategic responsibility. Six days later, the US Joint Chiefs of Staff (JCS) divided the theater into three areas: the Pacific Ocean Areas, the Southwest Pacific Area (commanded by General Douglas MacArthur), and the Southeast Pacific Area. The JCS designated Nimitz as "Commander in Chief, Pacific Ocean Areas", with operational control over all Allied units (air, land, and sea) in that area. Nimitz, in Hawaii, and his superior Admiral Ernest King, the Chief of Naval Operations, in Washington, rejected the plan of General Douglas MacArthur to advance on Japan through New Guinea and the Philippines and Formosa. Instead they proposed an island-hopping plan that would allow them to bypass most of the Japanese strength in the Central Pacific until they reached Okinawa. President Roosevelt compromised, giving both MacArthur and Nimitz their own theaters. The two Pacific theaters were favored, to the dismay of generals George Marshall and Dwight Eisenhower, who favored a Germany-first strategy. King and Nimitz provided MacArthur with some naval forces, but kept most of the carriers. However, when the time came to plan an invasion of Japan, MacArthur was given overall command.  Nimitz faced superior Japanese forces at the crucial defensive actions of the Battle of the Coral Sea and the Battle of Midway. The Battle of the Coral Sea, while a loss in terms of total damage suffered, resulted in the strategic success of turning back a Japanese invasion of Port Moresby on the island of New Guinea. Two Japanese carriers were temporarily taken out of action in the battle, which would deprive the Japanese of their use in the Midway operation that shortly followed. The Navy's intelligence team figured that the Japanese would be attacking Midway, so Nimitz moved all his available forces to the defense. The severe losses in Japanese carriers at Midway affected the balance of naval air power during the remainder of 1942, and was crucial in neutralizing Japanese offensive threats in the South Pacific. Naval engagements during the Battle of Guadalcanal left both forces severely depleted. However, with the allied advantage in land-based air power, the results were sufficient to secure Guadalcanal. The US and allied forces then undertook to neutralize remaining Japanese offensive threats with the Solomon Islands campaign and the New Guinea Campaign, while building capabilities for major fleet actions. In 1943, Midway became a forward submarine base, greatly enhancing US capabilities against Japanese shipping.  In terms of combat, 1943 was a relatively quiet year, but it proved decisive inasmuch as Nimitz gained the materiel and manpower needed to launch major fleet offensives to destroy Japanese power in the central Pacific region. This drive opened with the Gilbert and Marshall Islands campaign from November 1943 to February 1944, followed by the destruction of the strategic Japanese base at Truk Lagoon, and the Marianas campaign that brought the Japanese homeland within range of new strategic bombers. Nimitz's forces inflicted a decisive defeat on the Japanese fleet in the Battle of the Philippine Sea (June 19–20, 1944), which allowed the capture of Saipan, Guam, and Tinian. His Fleet Forces isolated enemy-held bastions on the central and eastern Caroline Islands and secured in quick succession Peleliu, Angaur, and Ulithi. In the Philippines, his ships destroyed much of the remaining Japanese naval power at the Battle of Leyte Gulf, October 24 to 26, 1944. With the loss of the Philippines, Japan's energy supply routes from Indonesia came under direct threat, crippling their war effort.  By Act of Congress, passed on December 14, 1944, the rank of fleet admiral — the highest rank in the Navy — was established. The next day President Franklin Roosevelt appointed Nimitz to that rank. Nimitz took the oath of that office on December 19, 1944.  In January 1945, Nimitz moved the headquarters of the Pacific Fleet forward from Pearl Harbor to Guam for the remainder of the war. Nimitz's wife remained in the continental United States for the duration of the war, and did not join her husband in Hawaii or Guam. In 1945, Nimitz's forces launched successful amphibious assaults on Iwo Jima and Okinawa and his carriers raided the home waters of Japan. In addition, Nimitz also ordered the Army Air Corps to mine the Japanese ports and waterways by air with B-29 Superfortresses in a successful mission called Operation Starvation, which severely interrupted the Japanese logistics.  On September 2, 1945, Nimitz signed as representative of the United States when Japan formally surrendered on board in Tokyo Bay. On October 5, 1945, which had been officially designated as "Nimitz Day" in Washington, D.C., Nimitz was personally presented a second Gold Star for the third award of the Navy Distinguished Service Medal by President Harry S. Truman "for exceptionally meritorious service as Commander in Chief, U.S. Pacific Fleet and Pacific Ocean Areas, from June 1944 to August 1945."

Post war.

On November 26, 1945, Nimitz's nomination as Chief of Naval Operations (CNO) was confirmed by the U.S. Senate, and on December 15, 1945, he relieved Fleet Admiral Ernest J. King. He had assured the President that he was willing to serve as the CNO for one two-year term, but no longer. He tackled the difficult task of reducing the most powerful navy in the world to a fraction of its war-time strength, while establishing and overseeing active and reserve fleets with the strength and readiness required to support national policy.  For the postwar trial of German Grand Admiral Karl Dönitz at the Nuremberg Trials in 1946, Nimitz furnished an affidavit in support of the practice of unrestricted submarine warfare, a practice that he himself had employed throughout the war in the Pacific. This evidence is widely credited as a reason why Dönitz was sentenced to only 10 years of imprisonment.  Nimitz endorsed an entirely new course for the U.S. Navy's future by way of supporting then-Captain Hyman G. Rickover's chain-of-command-circumventing proposal in 1947 to build, the world's first nuclear-powered vessel. As is noted at a display at the Nimitz Museum in Fredericksburg, Texas: "Nimitz's greatest legacy as CNO is arguably his support of Admiral Hyman Rickover's effort to convert the submarine fleet from diesel to nuclear propulsion."  From 1949 to 1953, Nimitz served as UN-appointed Plebiscite Administrator for Jammu and Kashmir. His proposed role as administrator was accepted by Pakistan but rejected by India.

Inactive duty as a fleet admiral.

Nimitz retired from office as CNO on December 15, 1947 and received a third Gold Star in lieu of a fourth Navy Distinguished Service Medal. However, since the rank of fleet admiral is a lifetime appointment, he remained on active duty for the rest of his life, with full pay and benefits. He and his wife, Catherine, moved to Berkeley, California. After he suffered a serious fall in 1964, he and Catherine moved to US Naval quarters on Yerba Buena Island in the San Francisco Bay.  In San Francisco, Nimitz served in the mostly ceremonial post as a special assistant to the Secretary of the Navy in the Western Sea Frontier. He worked to help restore goodwill with Japan after World War II by helping to raise funds for the restoration of the Japanese Imperial Navy battleship, Admiral Heihachiro Togo's flagship at the Battle of Tsushima in 1905.  Nimitz was also appointed as the United Nations Plebiscite Administrator for Kashmir on 31 December 1948. The terms of the plebiscite were that Pakistan would vacate regions of Kashmir under its control, and that India would remove additional military from Kashmir. But due to disagreements between the two nations regarding demilitarisation, the plebiscite is still pending.  Nimitz became a member of the Bohemian Club of San Francisco. In 1948, he sponsored a Bohemian dinner in honor of U.S. Army General Mark Clark, known for his campaigns in North Africa and Italy.  Nimitz served as a regent of the University of California during 1948–1956, where he had formerly been a faculty member as a professor of naval science for the Naval Reserve Officer Training Corps program. Nimitz was honored on October 17, 1964, by the University of California on Nimitz Day.

Personal life.

Nimitz married Catherine Vance Freeman (March 19, 1913 – February 1, 1979) on April 9, 1913, in Wollaston, Massachusetts. Nimitz and his wife had four children:  Catherine Vance graduated from the University of California, Berkeley, in 1934, became a music librarian with the Washington D.C. Public Library, and married U.S. Navy Commander James Thomas Lay (1909–2001), from St. Clair, Missouri, in Chester and Catherine's suite at the Fairfax Hotel in Washington, D.C., on March 9, 1945. She had met Lay in the summer of 1934 while visiting her parents in Southeast Asia.  Chester Nimitz, Jr., graduated from the U.S. Naval Academy in 1936 and served as a submariner in the Navy until his retirement in 1957, reaching the (post retirement) rank of rear admiral; he served as chairman of PerkinElmer from 1969–1980.  Anna Elizabeth ("Nancy") Nimitz was an expert on the Soviet economy at the RAND Corporation from 1952 until her retirement in the 1980s.  Sister Mary Aquinas (Nimitz) became a sister in the Order of Preachers (Dominicans), working at the Dominican University of California. She taught biology for 16 years, and was academic dean for 11 years, acting president for one year, and vice president for institutional research for 13 years before becoming the university's emergency preparedness coordinator. She held this job until her death, due to cancer, on February 27, 2006.

Death.

In late 1965, Nimitz suffered a stroke, complicated by pneumonia. In January 1966, he left the U.S. Naval Hospital (Oak Knoll) in Oakland to return home to his naval quarters. He died at home at age 80 on the evening of February 20 at Quarters One on Yerba Buena Island in San Francisco Bay. His funeral on February 24 was at the chapel of adjacent Naval Station Treasure Island and Nimitz was buried with full military honors at Golden Gate National Cemetery in San Bruno. He lies alongside his wife and his long-term friends Admiral Raymond A. Spruance, Admiral Richmond K. Turner, and Admiral Charles A. Lockwood and their wives, an arrangement made by all of them while living.

Memorials and legacy.

Besides the honor of a United States Great Americans series 50¢ postage stamp, the following institutions and locations have been named in honor of Nimitz:

Chester William Nimitz, Sr. (; February 24, 1885 – February 20, 1966) was a fleet admiral of the United States Navy. He played a major role in the naval history of World War II as Commander in Chief, U.S. Pacific Fleet and Commander in Chief, Pacific Ocean Areas, commanding Allied air, land, and sea forces during World War II.

Chester William Nimitz, Sr. (, Fredericksburg, Texas – ) a été le troisième et le plus jeune amiral de la Flotte de la Marine des États-Unis, durant la Seconde Guerre mondiale. Il a été nommé Commandant-en-chef de la Flotte du Pacifique (CINCPAC) en décembre 1941 et Commandant-en-chef interarmées des Zones de l'Océan Pacifique (CINCPOA) en avril 1942, commandements qu'il a exercés jusqu'en décembre 1945. Il a fini sa carrière comme premier Chef des Opérations navales de l'après-guerre.


Cubic curves in the plane of a triangle.

Suppose that "ABC" is a triangle with sidelengths,,. Relative to "ABC", many named cubics pass through well-known points. Examples shown below use two kinds of homogeneous coordinates: trilinear and barycentric.  To convert from trilinear to barycentric in a cubic equation, substitute as follows:  to convert from barycentric to trilinear, use  Many equations for cubics have the form  In the examples below, such equations are written more succinctly in "cyclic sum notation", like this:  The cubics listed below can be defined in terms of the isogonal conjugate, denoted by "X"*, of a point "X" not on a sideline of "ABC". A construction of "X"* follows. Let "L" be the reflection of line "XA" about the internal angle bisector of angle "A", and define "L" and "L" analogously. Then the three reflected lines concur in "X"*. In trilinear coordinates, if "X" = "x":"y":"z", then "X"* = ::.

Neuberg cubic.

Trilinear equation: [cyclic sum (cos "A" − 2 cos "B" cos "C")"x"("y" − "z")] = 0  Barycentric equation: [cyclic sum ("a"("b" + "c") + ("b" − "c") − 2"a")"x"("c""y" − "b""z")] = 0  The Neuberg cubic (named after Joseph Jean Baptiste Neuberg) is the locus of a point "X" such that "X"* is on the line "EX", where "E" is the Euler infinity point ("X"(30) in the Encyclopedia of Triangle Centers). Also, this cubic is the locus of "X" such that the triangle "XXX" is perspective to "ABC", where "XXX" is the reflection of "X" in the lines "BC", "CA", "AB", respectively  The Neuberg cubic passes through the following points: incenter, circumcenter, orthocenter, both Fermat points, both isodynamic points, the Euler infinity point, other triangle centers, the excenters, the reflections of "A", "B", "C" in the sidelines of "ABC", and the vertices of the six equilateral triangles erected on the sides of "ABC".  For a graphical representation and extensive list of properties of the Neuberg cubic, see K001 at Berhard Gibert's Cubics in the Triangle Plane.

Thomson cubic.

Trilinear equation: [cyclic sum "bcx"("y" − "z")] = 0  Barycentric equation: [cyclic sum "x"("c""y" − "b""z")] = 0  The Thomson cubic is the locus of a point "X" such that "X"* is on the line "GX", where "G" is the centroid.  The Thomson cubic passes through the following points: incenter, centroid, circumcenter, orthocenter, symmedian point, other triangle centers, the vertices "A", "B", "C", the excenters, the midpoints of sides "BC", "CA", "AB", and the midpoints of the altitudes of "ABC". For each point "P" on the cubic but not on a sideline of the cubic, the isogonal conjugate of "P" is also on the cubic.  For graphs and properties, see K002 at Cubics in the Triangle Plane.

Darboux cubic.

Trilinear equation: [cyclic sum (cos "A" − cos "B" cos "C")"x"("y" − "z")] = 0 Barycentric equation: [cyclic sum (2"a"("b" + "c") + ("b" − "c") − 3"a")"x"("c""y" − "b""z")] = 0  The Darboux cubic is the locus of a point "X" such that "X"* is on the line "LX", where "L" is the de Longchamps point. Also, this cubic is the locus of "X" such that the pedal triangle of "X" is the cevian of some point (which lies on the Lucas cubic). Also, this cubic is the locus of a point "X" such that the pedal triangle of "X" and the anticevian triangle of "X" are perspective; the perspector lies on the Thomson cubic.  The Darboux cubic passes through the incenter, circumcenter, orthocenter, de Longchamps point, other triangle centers, the vertices "A", "B", "C", the excenters, and the antipodes of "A", "B", "C" on the circumcircle. For each point "P" on the cubic but not on a sideline of the cubic, the isogonal conjugate of "P" is also on the cubic.  For graphics and properties, see K004 at Cubics in the Triangle Plane.

Napoleon–Feuerbach cubic.

Trilinear equation: [cyclic sum cos("B" − "C")"x"("y" − "z")] = 0 Barycentric equation: [cyclic sum ("a"("b" + "c") − ("b" − "c"))"x"("c""y" − "b""z")] = 0  The Napoleon–Feuerbach cubic is the locus of a point "X"* is on the line "NX", where "N" is the nine-point center, ("N" = "X"(5) in the Encyclopedia of Triangle Centers).  The Napoleon–Feuerbach cubic passes through the incenter, circumcenter, orthocenter, 1st and 2nd Napoleon points, other triangle centers, the vertices "A", "B", "C", the excenters, the projections of the centroid on the altitudes, and the centers of the 6 equilateral triangles erected on the sides of "ABC".  For a graphics and properties, see K005 at Cubics in the Triangle Plane.

Lucas cubic.

Trilinear equation: [cyclic sum (cos "A")"x"("b""y" − "c""z")] = 0 Barycentric equation: [cyclic sum ("b" + "c" − "a")"x"("y" − "z")] = 0  The Lucas cubic is the locus of a point "X" such that the cevian triangle of "X" is the pedal triangle of some point; the point lies on the Darboux cubic.  The Lucas cubic passes through the centroid, orthocenter, Gergonne point, Nagel point, de Longchamps point, other triangle centers, the vertices of the anticomplementary triangle, and the foci of the Steiner circumellipse.  For graphics and properties, see K007 at Cubics in the Triangle Plane.

1st Brocard cubic.

Trilinear equation: [cyclic sum "bc"("a" − "b""c")"x"("y" + "z"] = 0 Barycentric equation: [cyclic sum ("a" − "b""c")"x"("c""y" + "b""z"] = 0  Let "A"′"B"′"C"′ be the 1st Brocard triangle. For arbitrary point "X", let "X", "X", "X" be the intersections of the lines "XA"′, "XB"′, "XC"′ with the sidelines "BC", "CA", "AB", respectively. The 1st Brocard cubic is the locus of "X" for which the points "X", "X", "X" are collinear.  The 1st Brocard cubic passes through the centroid, symmedian point, Steiner point, other triangle centers, and the vertices of the 1st and 3rd Brocard triangles.  For graphics and properties, see K017 at Cubics in the Triangle Plane.

2nd Brocard cubic.

Trilinear equation: [cyclic sum "bc"("b" − "c")"x"("y" + "z"] = 0 Barycentric equation: [cyclic sum ("b" − "c")"x"("c""y" + "b""z"] = 0  The 2nd Brocard cubic is the locus of a point "X" for which the pole of the line "XX"* in the circumconic through "X" and "X"* lies on the line of the circumcenter and the symmedian point (i.e., the Brocard axis).  The 2nd Brocard cubic passes through the centroid, symmedian point, both Fermat points, both isodynamic points, the Parry point, other triangle centers, and the vertices of the 2nd and 4th Brocard triangles.  For a graphics and properties, see K018 at Cubics in the Triangle Plane.

1st equal areas cubic.

Trilinear equation: [cyclic sum "a"(b − "c")"x"("y" − "z"] = 0 Barycentric equation: [cyclic sum "a"("b" − "c")"x"("c""y" − "b""z"] = 0  The 1st equal areas cubic is the locus of a point "X" such that area of the cevian triangle of "X" equals the area of the cevian triangle of "X"*. Also, this cubic is the locus of "X" for which "X"* is on the line "S"*"X", where "S" is the Steiner point. ("S" = "X"(99) in the Encyclopedia of Triangle Centers).  The 1st equal areas cubic passes through the incenter, Steiner point, other triangle centers, the 1st and 2nd Brocard points, and the excenters.  For a graphics and properties, see K021 at Cubics in the Triangle Plane.

2nd equal areas cubic.

Trilinear equation: ("bz" + "cx")("cx" + "ay")("ay" + "bz") = ("bx" + "cy")("cy" + "ax")("az" + "bx")  Barycentric equation: [cyclic sum "a"("a" − "bc")"x"("c""y" − "b""z")] = 0  For any point "X" = "x":"y":"z" (trilinears), let "X" = "y":"z":"x" and "X" = "z":"x":"y". The 2nd equal areas cubic is the locus of "X" such that the area of the cevian triangle of "X" equals the area of the cevian triangle of "X".  The 2nd equal areas cubic passes through the incenter, centroid, symmedian point, and points in Encyclopedia of Triangle Centers indexed as "X"(31), "X"(105), "X"(238), "X"(292), "X"(365), "X"(672), "X"(1453), "X"(1931), "X"(2053), and others.  For a graphics and properties, see K155 at Cubics in the Triangle Plane.

In mathematics, a cubic plane curve is a plane algebraic curve "C" defined by a cubic equation applied to homogeneous coordinates for the projective plane; or the inhomogeneous version for the affine space determined by setting in such an equation. Here "F" is a non-zero linear combination of the third-degree monomials

En mathématiques, une courbe cubique est une courbe plane définie par une équation du troisième degré en les coordonnées homogènes ["X":"Y":"Z"] du plan projectif; ou bien c'est la version non homogène pour l'espace affine obtenue en faisant "Z" = 1 dans une telle équation. Ici "F" est une combinaison linéaire non nulle des monômes de degré trois


Types.

There are many cardiovascular diseases involving the blood vessels. They are known as vascular diseases.  There are also many cardiovascular diseases that involve the heart.

Risk factors.

There are many risk factors for heart diseases: age, sex, tobacco use, physical inactivity, excessive alcohol consumption, unhealthy diet, obesity, genetic predisposition and family history of cardiovascular disease, raised blood pressure (hypertension), raised blood sugar (diabetes mellitus), raised blood cholesterol (hyperlipidemia), undiagnosed celiac disease, psychosocial factors, poverty and low educational status, and air pollution. While the individual contribution of each risk factor varies between different communities or ethnic groups the overall contribution of these risk factors is very consistent. Some of these risk factors, such as age, sex or family history/genetic predisposition, are immutable; however, many important cardiovascular risk factors are modifiable by lifestyle change, social change, drug treatment (for example prevention of hypertension, hyperlipidemia, and diabetes). People with obesity are at increased risk of atherosclerosis of the coronary arteries.

Genetics.

Genetic factors influence the development of cardiovascular disease in men who are less than 55 years old and in women who are less than 65 years old. Cardiovascular disease in a person's parents increases their risk by 3 fold. Multiple single nucleotide polymorphisms (SNP) have been found to be associated with cardiovascular disease in genetic association studies, but usually, their individual influence is small, and genetic contributions to cardiovascular disease are poorly understood.

Age.

Age is the most important risk factor in developing cardiovascular or heart diseases, with approximately a tripling of risk with each decade of life. Coronary fatty streaks can begin to form in adolescence. It is estimated that 82 percent of people who die of coronary heart disease are 65 and older. Simultaneously, the risk of stroke doubles every decade after age 55.  Multiple explanations are proposed to explain why age increases the risk of cardiovascular/heart diseases. One of them relates to serum cholesterol level. In most populations, the serum total cholesterol level increases as age increases. In men, this increase levels off around age 45 to 50 years. In women, the increase continues sharply until age 60 to 65 years.  Aging is also associated with changes in the mechanical and structural properties of the vascular wall, which leads to the loss of arterial elasticity and reduced arterial compliance and may subsequently lead to coronary artery disease.

Sex.

Men are at greater risk of heart disease than pre-menopausal women. Once past menopause, it has been argued that a woman's risk is similar to a man's although more recent data from the WHO and UN disputes this. If a female has diabetes, she is more likely to develop heart disease than a male with diabetes.  Coronary heart diseases are 2 to 5 times more common among middle-aged men than women. In a study done by the World Health Organization, sex contributes to approximately 40% of the variation in sex ratios of coronary heart disease mortality. Another study reports similar results finding that sex differences explains nearly half the risk associated with cardiovascular diseases One of the proposed explanations for sex differences in cardiovascular diseases is hormonal difference. Among women, estrogen is the predominant sex hormone. Estrogen may have protective effects on glucose metabolism and hemostatic system, and may have direct effect in improving endothelial cell function. The production of estrogen decreases after menopause, and this may change the female lipid metabolism toward a more atherogenic form by decreasing the HDL cholesterol level while increasing LDL and total cholesterol levels.  Among men and women, there are differences in body weight, height, body fat distribution, heart rate, stroke volume, and arterial compliance. In the very elderly, age-related large artery pulsatility and stiffness is more pronounced among women than men. This may be caused by the women's smaller body size and arterial dimensions which are independent of menopause.

Tobacco.

Cigarettes are the major form of smoked tobacco. Risks to health from tobacco use result not only from direct consumption of tobacco, but also from exposure to second-hand smoke. Approximately 10% of cardiovascular disease is attributed to smoking; however, people who quit smoking by age 30 have almost as low a risk of death as never smokers.

Physical inactivity.

Insufficient physical activity (defined as less than 5 x 30 minutes of moderate activity per week, or less than 3 x 20 minutes of vigorous activity per week) is currently the fourth leading risk factor for mortality worldwide. In 2008, 31.3% of adults aged 15 or older (28.2% men and 34.4% women) were insufficiently physically active. The risk of ischemic heart disease and diabetes mellitus is reduced by almost a third in adults who participate in 150 minutes of moderate physical activity each week (or equivalent). In addition, physical activity assists weight loss and improves blood glucose control, blood pressure, lipid profile and insulin sensitivity. These effects may, at least in part, explain its cardiovascular benefits.

Diet.

High dietary intakes of saturated fat, trans-fats and salt, and low intake of fruits, vegetables and fish are linked to cardiovascular risk, although whether all these associations indicate causes is disputed. The World Health Organization attributes approximately 1.7 million deaths worldwide to low fruit and vegetable consumption. Frequent consumption of high-energy foods, such as processed foods that are high in fats and sugars, promotes obesity and may increase cardiovascular risk. The amount of dietary salt consumed may also be an important determinant of blood pressure levels and overall cardiovascular risk. There is moderate quality evidence that reducing saturated fat intake for at least two years reduces the risk of cardiovascular disease. High trans-fat intake has adverse effects on blood lipids and circulating inflammatory markers, and elimination of trans-fat from diets has been widely advocated. In 2018 the World Health Organization estimated that trans fats were the cause of more than half a million deaths per year. There is evidence that higher consumption of sugar is associated with higher blood pressure and unfavorable blood lipids, and sugar intake also increases the risk of diabetes mellitus. High consumption of processed meats is associated with an increased risk of cardiovascular disease, possibly in part due to increased dietary salt intake.

Alcohol.

The relationship between alcohol consumption and cardiovascular disease is complex, and may depend on the amount of alcohol consumed. There is a direct relationship between high levels of drinking alcohol and cardiovascular disease. Drinking at low levels without episodes of heavy drinking may be associated with a reduced risk of cardiovascular disease, but there is evidence that associations between moderate alcohol consumption and protection from stroke are non-causal. At the population level, the health risks of drinking alcohol exceed any potential benefits.

Celiac disease.

Untreated celiac disease can cause the development of many types of cardiovascular diseases, most of which improve or resolve with a gluten-free diet and intestinal healing. However, delays in recognition and diagnosis of celiac disease can cause irreversible heart damage.

Sleep.

Sleep disorders such as sleep disordered breathing and insomnia, as well as particularly short duration of sleep or particularly long duration of sleep, have been found to be associated with a higher cardiometabolic risk.

Socioeconomic disadvantage.

Cardiovascular disease affects low- and middle-income countries even more than high-income countries. There is relatively little information regarding social patterns of cardiovascular disease within low- and middle-income countries, but within high-income countries low income and low educational status are consistently associated with greater risk of cardiovascular disease. Policies that have resulted in increased socio-economic inequalities have been associated with greater subsequent socio-economic differences in cardiovascular disease implying a cause and effect relationship. Psychosocial factors, environmental exposures, health behaviours, and health-care access and quality contribute to socio-economic differentials in cardiovascular disease. The Commission on Social Determinants of Health recommended that more equal distributions of power, wealth, education, housing, environmental factors, nutrition, and health care were needed to address inequalities in cardiovascular disease and non-communicable diseases.

Air pollution.

Particulate matter has been studied for its short- and long-term exposure effects on cardiovascular disease. Currently, airborne particles under 2.5 micrometers in diameter (PM) are the major focus, in which gradients are used to determine CVD risk. Overall, long-term PM exposure increased rate of atherosclerosis and inflammation. In regards to short-term exposure (2 hours), every 25 μg/m of PM resulted in a 48% increase of CVD mortality risk. In addition, after only 5 days of exposure, a rise in systolic (2.8 mmHg) and diastolic (2.7 mmHg) blood pressure occurred for every 10.5 μg/m of PM. Other research has implicated PM in irregular heart rhythm, reduced heart rate variability (decreased vagal tone), and most notably heart failure. PM is also linked to carotid artery thickening and increased risk of acute myocardial infarction.

Cardiovascular risk assessment.

Existing cardiovascular disease or a previous cardiovascular event, such as a heart attack or stroke, is the strongest predictor of a future cardiovascular event. Age, sex, smoking, blood pressure, blood lipids and diabetes are important predictors of future cardiovascular disease in people who are not known to have cardiovascular disease. These measures, and sometimes others, may be combined into composite risk scores to estimate an individual's future risk of cardiovascular disease. Numerous risk scores exist although their respective merits are debated. Other diagnostic tests and biomarkers remain under evaluation but currently these lack clear-cut evidence to support their routine use. They include family history, coronary artery calcification score, high sensitivity C-reactive protein (hs-CRP), ankle–brachial pressure index, lipoprotein subclasses and particle concentration, lipoprotein(a), apolipoproteins A-I and B, fibrinogen, white blood cell count, homocysteine, N-terminal pro B-type natriuretic peptide (NT-proBNP), and markers of kidney function. High blood phosphorus is also linked to an increased risk.

Depression and traumatic stress.

There is evidence that mental health problems, in particular depression and traumatic stress, is linked to cardiovascular diseases. Whereas mental health problems are known to be associated with risk factors for cardiovascular diseases such as smoking, poor diet, and a sedentary lifestyle, these factors alone do not explain the increased risk of cardiovascular diseases seen in depression, stress, and anxiety. Moreover, posttraumatic stress disorder is independently associated with increased risk for incident coronary heart disease, even after adjusting for depression and other covariates.

Occupational exposure.

Little is known about the relationship between work and cardiovascular disease, but links have been established between certain toxins, extreme heat and cold, exposure to tobacco smoke, and mental health concerns such as stress and depression.

Non-chemical risk factors.

A 2015 SBU-report looking at non-chemical factors found an association for those:  Specifically the risk of stroke was also increased by exposure to ionizing radiation. Hypertension develops more often in those who experience job strain and who have shift-work. Differences between women and men in risk are small, however men risk suffering and dying of heart attacks or stroke twice as often as women during working life.

Chemical risk factors.

A 2017 SBU report found evidence that workplace exposure to silica dust, engine exhaust or welding fumes is associated with heart disease. Associations also exist for exposure to arsenic, benzopyrenes, lead, dynamite, carbon disulphide, carbon monoxide, metalworking fluids and occupational exposure to tobacco smoke. Working with the electrolytic production of aluminium or the production of paper when the sulphate pulping process is used is associated with heart disease. An association was also found between heart disease and exposure to compounds which are no longer permitted in certain work environments, such as phenoxy acids containing TCDD(dioxin) or asbestos.  Workplace exposure to silica dust or asbestos is also associated with pulmonary heart disease. There is evidence that workplace exposure to lead, carbon disulphide, phenoxyacids containing TCDD, as well as working in an environment where aluminum is being electrolytically produced, is associated with stroke.

Somatic mutations.

As of 2017, evidence suggests that certain leukemia-associated mutations in blood cells may also lead to increased risk of cardiovascular disease. Several large-scale research projects looking at human genetic data have found a robust link between the presence of these mutations, a condition known as clonal hematopoiesis, and cardiovascular disease-related incidents and mortality.

Pathophysiology.

Population-based studies show that atherosclerosis, the major precursor of cardiovascular disease, begins in childhood. The Pathobiological Determinants of Atherosclerosis in Youth (PDAY) study demonstrated that intimal lesions appear in all the aortas and more than half of the right coronary arteries of youths aged 7–9 years.  This is extremely important considering that 1 in 3 people die from complications attributable to atherosclerosis. In order to stem the tide, education and awareness that cardiovascular disease poses the greatest threat, and measures to prevent or reverse this disease must be taken.  Obesity and diabetes mellitus are often linked to cardiovascular disease, as are a history of chronic kidney disease and hypercholesterolaemia. In fact, cardiovascular disease is the most life-threatening of the diabetic complications and diabetics are two- to four-fold more likely to die of cardiovascular-related causes than nondiabetics.

Screening.

Screening ECGs (either at rest or with exercise) are not recommended in those without symptoms who are at low risk. This includes those who are young without risk factors. In those at higher risk the evidence for screening with ECGs is inconclusive. Additionally echocardiography, myocardial perfusion imaging, and cardiac stress testing is not recommended in those at low risk who do not have symptoms. Some biomarkers may add to conventional cardiovascular risk factors in predicting the risk of future cardiovascular disease; however, the value of some biomarkers is questionable. Ankle-brachial index (ABI), high-sensitivity C-reactive protein (hsCRP), and coronary artery calcium, are also of unclear benefit in those without symptoms as of 2018.  The NIH recommends lipid testing in children beginning at the age of 2 if there is a family history of heart disease or lipid problems. It is hoped that early testing will improve lifestyle factors in those at risk such as diet and exercise.  Screening and selection for primary prevention interventions has traditionally been done through absolute risk using a variety of scores (ex. Framingham or Reynolds risk scores). This stratification has separated people who receive the lifestyle interventions (generally lower and intermediate risk) from the medication (higher risk). The number and variety of risk scores available for use has multiplied, but their efficacy according to a 2016 review was unclear due to lack of external validation or impact analysis. Risk stratification models often lack sensitivity for population groups and do not account for the large number of negative events among the intermediate and low risk groups. As a result, future preventative screening appears to shift toward applying prevention according to randomized trial results of each intervention rather than large-scale risk assessment.

Prevention.

Up to 90% of cardiovascular disease may be preventable if established risk factors are avoided. Currently practiced measures to prevent cardiovascular disease include:  Most guidelines recommend combining preventive strategies. A 2015 Cochrane Review found some evidence that interventions aiming to reduce more than one cardiovascular risk factor may have beneficial effects on blood pressure, body mass index and waist circumference; however, evidence was limited and the authors were unable to draw firm conclusions on the effects on cardiovascular events and mortality. For adults without a known diagnosis of hypertension, diabetes, hyperlipidemia, or cardiovascular disease, routine counseling to advise them to improve their diet and increase their physical activity has not been found to significantly alter behavior, and thus is not recommended. Another Cochrane review suggested that simply providing people with a cardiovascular disease risk score may reduce cardiovascular disease risk factors by a small amount compared to usual care. However, there was some uncertainty as to whether providing these scores had any effect on cardiovascular disease events. It is unclear whether or not dental care in those with periodontitis affects their risk of cardiovascular disease.

Diet.

A diet high in fruits and vegetables decreases the risk of cardiovascular disease and death. Evidence suggests that the Mediterranean diet may improve cardiovascular outcomes. There is also evidence that a Mediterranean diet may be more effective than a low-fat diet in bringing about long-term changes to cardiovascular risk factors (e.g., lower cholesterol level and blood pressure). The DASH diet (high in nuts, fish, fruits and vegetables, and low in sweets, red meat and fat) has been shown to reduce blood pressure, lower total and low density lipoprotein cholesterol and improve metabolic syndrome; but the long-term benefits have been questioned. A high fiber diet is associated with lower risks of cardiovascular disease.  Worldwide, dietary guidelines recommend a reduction in saturated fat, and although the role of dietary fat in cardiovascular disease is complex and controversial there is a long-standing consensus that replacing saturated fat with unsaturated fat in the diet is sound medical advice. Total fat intake has not been found to be associated with cardiovascular risk. A 2020 systematic review found moderate quality evidence that reducing saturated fat intake for at least 2 years caused a reduction in cardiovascular events. A 2015 meta-analysis of observational studies however did not find a convincing association between saturated fat intake and cardiovascular disease. Variation in what is used as a substitute for saturated fat may explain some differences in findings. The benefit from replacement with polyunsaturated fats appears greatest, while replacement of saturated fats with carbohydrates does not appear to have a beneficial effect. A diet high in trans fatty acids is associated with higher rates of cardiovascular disease, and in 2015 the Food and Drug Administration (FDA) determined that there was 'no longer a consensus among qualified experts that partially hydrogenated oils (PHOs), which are the primary dietary source of industrially produced trans fatty acids (IP-TFA), are generally recognized as safe (GRAS) for any use in human food'. There is no convincing evidence that dietary supplements of omega-3 fatty acids (a type of polysaturated fat in oily fish) added to diet improve cardiovascular risk. A 2014 Cochrane review found unclear benefit of recommending a low-salt diet in people with high or normal blood pressure. In those with heart failure, after one study was left out, the rest of the trials show a trend to benefit. Another review of dietary salt concluded that there is strong evidence that high dietary salt intake increases blood pressure and worsens hypertension, and that it increases the number of cardiovascular disease events; both as a result of the increased blood pressure "and", quite likely, through other mechanisms. Moderate evidence was found that high salt intake increases cardiovascular mortality; and some evidence was found for an increase in overall mortality, strokes, and left ventricular hypertrophy.

Medication.

Blood pressure medication reduces cardiovascular disease in people at risk, irrespective of age, the baseline level of cardiovascular risk, or baseline blood pressure. The commonly-used drug regimens have similar efficacy in reducing the risk of all major cardiovascular events, although there may be differences between drugs in their ability to prevent specific outcomes. Larger reductions in blood pressure produce larger reductions in risk, and most people with high blood pressure require more than one drug to achieve adequate reduction in blood pressure. Adherence to medications is often poor and while mobile phone text messaging has been tried to improve adherence, there is insufficient evidence that it alters secondary prevention of cardiovascular disease.  Statins are effective in preventing further cardiovascular disease in people with a history of cardiovascular disease. As the event rate is higher in men than in women, the decrease in events is more easily seen in men than women. In those at risk, but without a history of cardiovascular disease (primary prevention), statins decrease the risk of death and combined fatal and non-fatal cardiovascular disease. The benefit, however, is small. A United States guideline recommends statins in those who have a 12% or greater risk of cardiovascular disease over the next ten years. Niacin, fibrates and CETP Inhibitors, while they may increase HDL cholesterol do not affect the risk of cardiovascular disease in those who are already on statins. Fibrates lower the risk of cardiovascular and coronary events, but there is no evidence to suggest that they reduce all-cause mortality.  Anti-diabetic medication may reduce cardiovascular risk in people with Type 2 Diabetes, although evidence is not conclusive. A meta-analysis in 2009 including 27,049 participants and 2,370 major vascular events showed a 15% relative risk reduction in cardiovascular disease with more-intensive glucose lowering over an average follow-up period of 4.4 years, but an increased risk of major hypoglycemia.  Aspirin has been found to be of only modest benefit in those at low risk of heart disease as the risk of serious bleeding is almost equal to the benefit with respect to cardiovascular problems. In those at very low risk, including those over the age of 70, it is not recommended. The United States Preventive Services Task Force recommends against use of aspirin for prevention in women less than 55 and men less than 45 years old; however, in those who are older it is recommends in some individuals.  The use of vasoactive agents for people with pulmonary hypertension with left heart disease or hypoxemic lung diseases may cause harm and unnecessary expense.

Physical activity.

Exercise-based cardiac rehabilitation following a heart attack reduces the risk of death from cardiovascular disease and leads to less hospitalizations. There have been few high quality studies of the benefits of exercise training in people with increased cardiovascular risk but no history of cardiovascular disease.  A systematic review estimated that inactivity is responsible for 6% of the burden of disease from coronary heart disease worldwide. The authors estimated that 121,000 deaths from coronary heart disease could have been averted in Europe in 2008, if physical inactivity had been removed. A Cochrane review found some evidence that yoga has beneficial effects on blood pressure and cholesterol, but studies included in this review were of low quality. Tentative evidence suggests that home-based exercise programs may be more efficient at improving exercise adherence.

Dietary supplements.

While a healthy diet is beneficial, the effect of antioxidant supplementation (vitamin E, vitamin C, etc.) or vitamins has not been shown to protect against cardiovascular disease and in some cases may possibly result in harm. Mineral supplements have also not been found to be useful. Niacin, a type of vitamin B3, may be an exception with a modest decrease in the risk of cardiovascular events in those at high risk. Magnesium supplementation lowers high blood pressure in a dose dependent manner. Magnesium therapy is recommended for people with ventricular arrhythmia associated with torsades de pointes who present with long QT syndrome as well as for the treatment of people with digoxin intoxication-induced arrhythmias. There is no evidence to support omega-3 fatty acid supplementation.

Management.

Cardiovascular disease is treatable with initial treatment primarily focused on diet and lifestyle interventions. Influenza may make heart attacks and strokes more likely and therefore influenza vaccination may decrease the chance of cardiovascular events and death in people with heart disease.  Proper CVD management necessitates a focus on MI and stroke cases due to their combined high mortality rate, keeping in mind the cost-effectiveness of any intervention, especially in developing countries with low or middle-income levels. Regarding MI, strategies using aspirin, atenolol, streptokinase or tissue plasminogen activator have been compared for quality-adjusted life-year (QALY) in regions of low and middle income. The costs for a single QALY for aspirin and atenolol were less than $25, streptokinase was about $680, and t-PA was $16,000. Aspirin, ACE inhibitors, beta-blockers, and statins used together for secondary CVD prevention in the same regions showed single QALY costs of $350.  A 2018 Cochrane review did not find any additional benefit in terms of mortality and serious adverse events when blood pressure targets were lowered to ≤ 135/85 mmHg from ≤ 140 to 160/90 to 100 mmHg.

Epidemiology.

Cardiovascular diseases are the leading cause of death worldwide and in all regions except Africa. In 2008, 30% of all global death was attributed to cardiovascular diseases. Death caused by cardiovascular diseases are also higher in low- and middle-income countries as over 80% of all global deaths caused by cardiovascular diseases occurred in those countries. It is also estimated that by 2030, over 23 million people will die from cardiovascular diseases each year.  It is estimated that 60% of the world's cardiovascular disease burden will occur in the South Asian subcontinent despite only accounting for 20% of the world's population. This may be secondary to a combination of genetic predisposition and environmental factors. Organizations such as the Indian Heart Association are working with the World Heart Federation to raise awareness about this issue.

Research.

There is evidence that cardiovascular disease existed in pre-history, and research into cardiovascular disease dates from at least the 18th century. The causes, prevention, and/or treatment of all forms of cardiovascular disease remain active fields of biomedical research, with hundreds of scientific studies being published on a weekly basis.  Recent areas of research include the link between inflammation and atherosclerosis the potential for novel therapeutic interventions, and the genetics of coronary heart disease.

Cardiovascular disease (CVD) is a class of diseases that involve the heart or blood vessels. CVD includes coronary artery diseases (CAD) such as angina and myocardial infarction (commonly known as a heart attack). Other CVDs include stroke, heart failure, hypertensive heart disease, rheumatic heart disease, cardiomyopathy, abnormal heart rhythms, congenital heart disease, valvular heart disease, carditis, aortic aneurysms, peripheral artery disease, thromboembolic disease, and venous thrombosis. The underlying mechanisms vary depending on the disease. Coronary artery disease, stroke, and peripheral artery disease involve atherosclerosis. This may be caused by high blood pressure, smoking, diabetes mellitus, lack of exercise, obesity, high blood cholesterol, poor diet, and excessive alcohol consumption, among others. High blood pressure is estimated to account for approximately 13% of CVD deaths, while tobacco accounts for 9%, diabetes 6%, lack of exercise 6% and obesity 5%. Rheumatic heart disease may follow untreated strep throat. It is estimated that up to 90% of CVD may be preventable. Prevention of CVD involves improving risk factors through: healthy eating, exercise, avoidance of tobacco smoke and limiting alcohol intake. Treating risk factors, such as high blood pressure, blood lipids and diabetes is also beneficial. Treating people who have strep throat with antibiotics can decrease the risk of rheumatic heart disease. The use of aspirin in people, who are otherwise healthy, is of unclear benefit. Cardiovascular diseases are the leading cause of death in all areas of the world except Africa. Together CVD resulted in 17.9 million deaths (32.1%) in 2015, up from 12.3 million (25.8%) in 1990. Deaths, at a given age, from CVD are more common and have been increasing in much of the developing world, while rates have declined in most of the developed world since the 1970s. Coronary artery disease and stroke account for 80% of CVD deaths in males and 75% of CVD deaths in females. Most cardiovascular disease affects older adults. In the United States 11% of people between 20 and 40 have CVD, while 37% between 40 and 60, 71% of people between 60 and 80, and 85% of people over 80 have CVD. The average age of death from coronary artery disease in the developed world is around 80 while it is around 68 in the developing world. Diagnosis of disease typically occurs seven to ten years earlier in men as compared to women.

Une maladie cardiovasculaire, ou maladie cardioneurovasculaire, est une maladie qui concerne le cœur et la circulation sanguine. Dans les pays occidentaux, son expression la plus courante est la maladie coronarienne, responsable de l'angine de poitrine ou encore des infarctus.


Early life and reign.

Born in Moscow on, the son of Tsar Michael and Eudoxia Streshneva, the sixteen year old Alexei acceded to the throne after his father's death on 12 July 1645. In August, the Tsar's mother died, and following a pilgrimage to Sergiyev Posad he was crowned on 28 September in the Dormition Cathedral. He was committed to the care of his tutor Boris Morozov, a shrewd boyar open to Western ideas.  Morozov's pursued a peaceful foreign policy, securing a truce with the Polish-Lithuanian Commonwealth and carefully avoiding complications with the Ottoman Empire. His domestic policy aimed at limiting the privileges of foreign traders and abolishing useless and expensive court offices. On 17 January 1648 Morozov procured the marriage of the tsar with Maria Miloslavskaya, himself marrying her sister, Anna, ten days later, both daughters of Ilya Danilovich Miloslavsky.  Morozov was regarded as a corrupt, self-seeking boyar and was accused of sorcery and witchcraft. In May 1648 Muscovites rose against his faction in the Salt Riot, and the young Tsar was compelled to dismiss them and exile Boris to the Kirillo-Belozersky Monastery. Four months later, Boris secretly returned to Moscow to regain some of his power.  The popular discontent demonstrated by the riot was partially responsible for Alexis' 1649 issuance of a new legal code, the Sobornoye Ulozhenie.

Later reign.

Military reform.

In 1648, using the experience of creating regiments of the foreign system during the reign of his father, Alexis began reforming the army.  The main direction of the reform was the mass creation of New Order Regiments: Reiters, Soldiers, Dragoons and Hussars. These regiments formed the backbone of the new army of Tsar Alexis. To fulfill the reform goals, a large number of European military specialists were hired for service. This became possible because of the end of the Thirty Years' War, which created a colossal market for military professionals in Europe.

Rebellions.

Throughout his reign, Alexei faced rebellions across Russia. After resolving the 1648 Salt Riot Alexei faced rebellions in 1650 in the cities of Pskov and Great Novgorod. Alexei put down the Novgorod rebellion quickly, but was unable to subdue Pskov, and was forced to promise the city amnesty in return for surrender. The Metropolitan Nikon distinguished himself at Great Novgorod and in 1651 became the Tsar's chief minister.  By the 1660s, Alexei's wars with Poland and Sweden had put an increasing strain on the Russian economy and public finances. In response, Alexei's government had begun minting large numbers of copper coins in 1654 to increase government revenue but this led to a devaluation of the ruble and a severe financial crisis. As a result, angry Moscow residents revolted in the 1662 Copper Riot, which was put down violently.  In 1669, the Cossacks along the Don in southern Russia erupted in rebellion. The rebellion was led by Stenka Razin, a disaffected Don Cossack who had captured the Russian terminus of Astrakhan. From 1670 to 1671, Razin seized multiple towns along the Volga River. The turning point in his campaign was his failed siege of Simbirsk in October 1670. Razin was finally captured on the Don in April 1671, and was drawn and quartered in Moscow.

War against Safavid Iran.

In 1651 Safavid troops attacked Russian fortifications in the North Caucasus. The main issue involved the expansion of a Russian garrison on the Koy Su River, as well as the construction of several new fortresses, in particular the one built on the Iranian side of the Terek River. The successful Safavid offensive resulted in the destruction of the Russian fortress and its garrison being expelled. In 1653 Alexis, initially thinking about sending the Zaporozhian Cossacks, eventually decided to send an embassy to Persia for a peaceful settlement of the conflict. In August 1653 courtier Prince Ivan Lobanov-Rostov and steward Ivan Komynin traveled from Astrakhan to Isfahan. Shah Abbas II agreed to settle the conflict, stating that the conflict was initiated without his consent.

Wars against Poland and Sweden.

In 1653 the weakness and disorder of Poland, which had just emerged from the Khmelnytsky Uprising, encouraged Alexei to attempt to annex the old Rus’ lands. On 1 October 1653 a national assembly met at Moscow to sanction the war and find the means of carrying it out, and in April 1654 the army was blessed by Nikon, who had been elected patriarch in 1652.  The campaign of 1654 was an uninterrupted triumph, and scores of towns, including the important fortress of Smolensk, fell into the hands of the Russians. Ukrainian Hetman Bogdan Khmelnitsky appealed to Tsar Alexei for protection from the Poles, and the Treaty of Pereyaslav brought about Russian dominance of the Cossack Hetmanate in Left-Bank Ukraine.  In the summer of 1655, a sudden invasion by Charles X of Sweden briefly swept the Polish state out of existence, in what became known as the Deluge. The Russians, unopposed, quickly appropriated nearly everything that was not already occupied by the Swedes. When the Poles offered to negotiate, the whole grand-duchy of Lithuania was the least of the demands made by Alexei. However Alexei and the king of Sweden quarrelled over the apportionment of the spoils, and at the end of May 1656, with encouragement by the Habsburg emperor and the other enemies of Sweden, Alexei declared war on Sweden.  Great things were expected by Russia of the Swedish war, but nothing came of it. Dorpat was taken, but countless multitudes of men were lost in vain before Riga. In the meantime Poland had so far recovered herself as to become a much more dangerous foe than Sweden, and, as it was impossible to wage war with both simultaneously, the tsar resolved to rid himself of the Swedes first. In the Peace of Kardis (2 July 1661), Russia retroceded all her conquests.  The Polish war dragged on for six years longer and was then concluded by the Truce of Andrusovo (11 February 1667), nominally for thirteen years, which proved the most durable of treaties. According to the truce, Polotsk and Polish Livonia were restored to Poland, but the more important cities of Smolensk and Kiev remained in the hands of Russia together with the whole eastern bank of the Dnieper River. This truce was the achievement of Afanasy Ordin-Nashchokin, the first Russian chancellor and diplomat in the modern sense, who after the disgrace of Nikon became the tsar's first minister until 1670, when he was superseded by the equally able Artamon Matveyev, whose beneficent influence prevailed to the end of Alexei's reign.

Response to English Civil War.

When Charles I of England was beheaded by the Parliamentarians under Oliver Cromwell in 1649, an outraged Alexei broke off diplomatic relations with England and accepted Royalist refugees in Moscow. He also banned all English merchants from his country (notably members of the Muscovy Company) and provided financial assistance to "the disconsolate widow of that glorious martyr, King Charles I."

Schism with the Old Believers.

In 1653, Patriarch Nikon established a series of reforms that aimed to bring the practices of the Russian Orthodox Church into line with its Greek counterpart. Most notably, the church began to mandate the use of three fingers instead of two in making the sign of the cross. This resulted in significant dissent among the church community. Nevertheless, Alexei continued to support Nikon until 1658, when Nikon abandoned his post due to a personal insult, leaving the seat of the patriarch vacant.  In 1666, the tsar convened the Great Moscow Synod, which was attended by Patriarch Macarios III of Antioch and Patriarch Paisius of Alexandria, in order to address the problems caused by Nikon. The synod agreed to formally depose Nikon, and also decided to excommunicate all who opposed the reforms of the church; those opponents broke away from the official Russian Orthodox Church to form the Old Believers movement.

Assessment.

According to the "Encyclopædia Britannica" Eleventh Edition:  Alexei's letters were first published by Pyotr Bartenev in 1856. They have earned him a place in the history of Russian literature, as assessed by D.S. Mirsky:  A few private letters and an instruction to his falconers is all we have of him. But it is sufficient for Sergey Platonov to proclaim him the most attractive of Russian monarchs. He acquired the moniker "Tishayshy", which means "most quiet" or "most peaceful". He received this moniker through the ways he behaved- he would be kind and friendly, but the sounds created from instruments would provoke him. Certain aspects of Russian Orthodoxy, not its most purely spiritual, but its aesthetic and worldly aspects, found in him their most complete expression. The essence of Alexei's personality is a certain spiritual Epicureanism, manifested in an optimistic Christian faith, in a profound, but unfanatical, attachment to the traditions and ritual of the Church, in a desire to see everyone round him happy and at peace, and in a highly developed capacity to extract a quiet and mellow enjoyment from all things.

Family and children.

Alexei's first marriage to Miloslavskaya was harmonious and felicitous. She bore him thirteen children (five sons and eight daughters) in twenty-one years of marriage, and died only weeks after her thirteenth childbirth. Four sons survived her (Alexei, Fyodor, Semyon, and Ivan), but within six months of her death, two of these were dead, including Alexei, the 15-year-old heir to the throne. The couple's children were:  Alexei remarried on 1 February 1671 to Nataliya Kyrillovna Naryshkina (1 September 16514 February 1694). She was brought up in the house of Artamon Matveyev, whose wife was the Scottish-descended Mary Hamilton. Their children were:

Alexei Mikhailovich (; – ) was the Tsar of Russia from 1645 until his death in 1676. His reign saw wars with Poland and Sweden, schism in the Russian Orthodox Church, and the major Cossack revolt of Stenka Razin. Nevertheless, at the time of his death Russia spanned almost.

Alexis Mikhaïlovitch, (en ) dit « le Tsar très paisible », né le et mort le ), fils de Michel Romanov (1596-1645) et d'Eudoxie Lukianovna Strechnieff (1608-1645), est tsar de Russie de 1645 à 1676.


"The German Trilogy".

"The Damned" has been regarded as the first of Visconti's films described as "The German Trilogy", followed by "Death in Venice" (1971) and "Ludwig" (1973). Author Henry Bacon, in his book "Visconti: Explorations of Beauty and Decay" (1998), specifically categorizes these films together in a chapter "Visconti & Germany". Visconti's earlier films had analyzed Italian society during the Risorgimento and postwar periods. Peter Bondanella's "Italian Cinema" (2002) depicts the trilogy as a move to take a broader view of European politics and culture. Stylistically, "They emphasize lavish sets and costumes, sensuous lighting, painstakingly slow camerawork, and a penchant for imagery reflecting subjective states or symbolic values", comments Bondanella.

Plot.

The film centers on the Essenbecks, a wealthy industrialist family who have begun doing business with the Nazi Party. On the night of the Reichstag fire, the family's conservative patriarch, Baron Joachim von Essenbeck, who represents the old aristocratic Germany and detests Adolf Hitler, is murdered. Herbert Thalmann, the family firm's vice president, who openly opposes the Nazis, is framed for the crime. He escapes the grasp of the Gestapo, but his wife Elizabeth and their children do not.  The family's empire passes to the control of an unscrupulous relative, the boorish SA officer Konstantin. Waiting in the wings are his son Günther, a sensitive and troubled student, and his nephew, Martin, an amoral, sexually deviant playboy who is secretly molesting his young cousin as well as a poor Jewish girl. Martin is dominated by his possessive mother, Sophie, the widow of Baron Joachim's only son, a fallen World War I hero.  Friedrich Bruckmann, an employee of the family firm and Sophie's lover, ascends in power despite his lowly social status, thanks to Sophie's support and the SS officer and family relation Aschenbach, who pits family factions against each other to move their steel and munition works into state control. Friedrich kills Konstantin in the SS coup against the SA during its 1934 meeting to deal with its dissatisfaction with Hitler. Known as The Night of the Long Knives, the SA meeting and the subsequent executions of its leaders by the SS is portrayed as a homosexual orgy and bloody gangster-style massacre. Aschenbach then dismisses Friedrich, who now controls the family fortunes, as a weak social climber and not a loyal Nazi.  Herbert Thalmann then returns to the family table. He reveals that his wife and children were sent to Dachau concentration camp, where his wife died; he is handing himself over to the Gestapo in return for the freedom of his children. Aschenbach makes a deal with the discounted and ignored heir, Martin, to remove Friedrich and Sophie from control, so that Martin may get what is owed him. Martin has sex with his mother, who falls into a catatonic state. Now in the SS, Martin allows Friedrich, who by decree has inherited the name and title of von Essenbeck, to wed his mother, and then hands them poison to commit suicide. He then hands over the family's steelworks to the Nazi government, which means that the way to war is more than secured.

Response.

The film opened to worldwide acclaim. It received an Oscar nomination for Best Original Screenplay and was named Best Foreign Film by the National Board of Review. Among the international cast, Helmut Berger was singled out for his performance as Martin, a vicious sexual deviant who uses his amoral appetites to his own twisted ends. The film was the tenth-most popular movie at the French box office in 1970.  The film has appeared on critics' lists such as the "New York Times Best 1000 Movies Ever Made" and "Halliwell's Top 1000: The Ultimate Movie Countdown".  The film's entry in the "Lexikon des Internationalen Films" praises it for its presentation of the connection of "moral decadence, sexual neurosis, aetheticist death wish, narcisist self-centeredness and political opportunism", also saying that the effect is partially weakened by the film's "decorative circuitousness and artificial stylisation."  The film was given an "X" rating by the MPAA and was heavily edited when shown on CBS television late at night. Warner Bros. submitted the film for re-classification for its DVD release of the film in 2004. The film's rating was changed from an "X" to an "R".

The Damned (Italian title: "La caduta degli dei", lit. "The Fall of the Gods") is a 1969 Italian-German historical drama film written and directed by Luchino Visconti. The plot centers on the Essenbecks, a wealthy industrialist family who have begun doing business with the Nazi Party, a thinly veiled reference to the Essen-based Krupp family of steel industrialists.

Les Damnés (titre original ; en français : "la Chute des dieux") est un film germano-italien réalisé par Luchino Visconti, sorti en 1969.


Design and development.

Background and requirements.

The Korean War showed that World War II-era piston-engine transports—Fairchild C-119 Flying Boxcars, Douglas C-47 Skytrains and Curtiss C-46 Commandos—were no longer adequate. Thus, on 2 February 1951, the United States Air Force issued a General Operating Requirement (GOR) for a new transport to Boeing, Douglas, Fairchild, Lockheed, Martin, Chase Aircraft, North American, Northrop, and Airlifts Inc.  The new transport would have a capacity

Design phase.

The Hercules resembled a larger four-engine brother to the C-123 Provider with a similar wing and cargo ramp layout that evolved from the Chase XCG-20 Avitruc, which in turn, was first designed and flown as a cargo glider in 1947. The Boeing C-97 Stratofreighter had rear ramps, which made it possible to drive vehicles onto the airplane (also possible with forward ramp on a C-124). The ramp on the Hercules was also used to airdrop cargo, which included a Low-altitude parachute-extraction system for Sheridan tanks and even dropping large improvised "daisy cutter" bombs. The new Lockheed cargo plane design possessed a range of, takeoff capability from short and unprepared strips, and the ability to fly with one engine shut down.  Fairchild, North American, Martin, and Northrop declined to participate. The remaining five companies tendered a total of ten designs: Lockheed two, Boeing one, Chase three, Douglas three, and Airlifts Inc. one. The contest was a close affair between the lighter of the two Lockheed (preliminary project designation L-206) proposals and a four-turboprop Douglas design.  The Lockheed design

Improved versions.

The C-130B model was developed to complement the A-models that had previously been delivered, and incorporated new features, particularly increased fuel capacity in the form of auxiliary tanks built into the center wing section and an AC electrical system. Four-bladed Hamilton Standard propellers replaced the Aeroproducts three-blade propellers that distinguished the earlier A-models. The C-130B had ailerons operated by hydraulic pressure that was increased from to, as well as uprated engines and four-blade propellers that were standard until the J-model.  The

Further developments.

The "C-130H" model has updated Allison T56-A-15 turboprops, a redesigned outer wing, updated avionics and other minor improvements. Later "H" models had a new, fatigue-life-improved, center wing that was retrofitted to many earlier H-models. For structural reasons, some models are required to land with reduced amounts of fuel when carrying heavy cargo, reducing usable range. The H model remains in widespread use with the United States Air Force (USAF) and many foreign air forces. Initial deliveries began in 1964 (to the RNZAF), remaining in production until 1996. An improved C-130H was introduced in 1974, with Australia purchasing 12 of type in 1978 to replace the original 12 C-130A models, which had first entered Royal Australian Air Force (RAAF) service in 1958. The U.S. Coast Guard employs the HC-130H for long-range search and rescue, drug interdiction, illegal migrant patrols, homeland security, and logistics. C-130H models produced from 1992 to 1996 were designated as C-130H3 by the USAF. The "3" denoting the third variation

Enhanced models.

The "MC-130E Combat Talon" was developed for the USAF during the Vietnam War to support special operations missions in Southeast Asia, and led to both the "MC-130H Combat Talon II" as well as a family of other special missions aircraft. 37 of the earliest models currently operating with the Air Force Special Operations Command (AFSOC) are scheduled to be replaced by new-production MC-130J versions. The EC-130 Commando Solo is another special missions variant within AFSOC, albeit operated solely by an AFSOC-gained wing in the Pennsylvania Air National Guard, and is a psychological operations/information operations (PSYOP/IO) platform equipped as an aerial radio station and television stations able to transmit messaging over commercial frequencies. Other versions of the EC-130, most notably the EC-130H Compass Call, are also special variants, but are assigned to the Air Combat Command (ACC). The AC-130 gunship was first developed during the Vietnam War to provide close air support and other ground-attack duties. The "HC-130" is a family of long-range search and rescue variants used

Next generation.

In the 1970s, Lockheed proposed a C-130 variant with turbofan engines rather than turboprops, but the U.S. Air Force preferred the takeoff performance of the existing aircraft. In the 1980s, the C-130 was intended to be replaced by the Advanced Medium STOL Transport project. The project was canceled and the C-130 has remained in production.  Building on lessons learned, Lockheed Martin modified a commercial variant of the C-130 into a High Technology Test Bed (HTTB). This test aircraft set numerous short takeoff and landing performance records and significantly expanded the database for future derivatives of the C-130. Modifications made to the HTTB included extended chord ailerons, a long chord rudder, fast-acting double-slotted trailing edge flaps, a high-camber wing leading edge extension, a larger dorsal fin and dorsal fins, the addition of three spoiler panels to each wing upper surface, a long-stroke main and nose landing gear system, and

Upgrades and changes.

In 2000, Boeing was awarded a contract to develop an Avionics Modernization Program kit for the C-130. The program was beset with delays and cost overruns until project restructuring in 2007. On 2 September 2009, Bloomberg news reported that the planned Avionics Modernization Program (AMP) upgrade to the older C-130s would be dropped to provide more funds for the F-35, CV-22 and airborne tanker replacement programs. However, in June 2010, Department of Defense approved funding for the initial

Replacement.

In October 2010, the Air Force released a capabilities request for information (CRFI) for the development of a new airlifter to replace the C-130. The new aircraft is to carry a 190 percent greater payload and assume the mission of mounted vertical maneuver (MVM). The greater payload and mission would enable it to carry medium-weight armored vehicles and drop them off at locations without long runways. Various options are being considered, including new or upgraded fixed-wing designs, rotorcraft, tiltrotors, or even

Operational history.

Military.

The first batch of C-130A production aircraft were delivered beginning in 1956 to the 463d Troop Carrier Wing at Ardmore AFB, Oklahoma and the 314th Troop Carrier Wing at Sewart AFB, Tennessee. Six additional squadrons were assigned to the 322d Air Division in Europe and the 315th Air Division in the Far East. Additional aircraft were modified for electronics intelligence work and assigned to Rhein-Main Air Base, Germany while modified RC-130As were assigned to the Military Air Transport Service (MATS) photo-mapping division. The C-130A entered service with the U.S. Air Force in December 1956.  In 1958, a U.S. reconnaissance C-130A-II of the 7406th Support Squadron was shot down over Armenia by four Soviet MiG-17s along the Turkish-Armenian border during a routine mission.  Australia became the first non-American force to operate the C-130A Hercules with 12 examples being delivered from late 1958. The Royal Canadian Air Force became another early user with the delivery of four B-models (Canadian designation C-130 Mk I) in October / November 1960.  In 1963, a Hercules achieved and still holds the record for the largest and heaviest aircraft to land on an aircraft carrier. During October and November that year, a USMC KC-130F (BuNo "149798"), loaned to the U.S. Naval Air Test Center, made 29 touch-and-go landings, 21 unarrested full-stop landings and 21 unassisted take-offs on at a number of different weights. The pilot, Lieutenant (later Rear Admiral) James H. Flatley III, USN, was awarded the Distinguished Flying Cross for his role in this test series. The tests were highly successful, but the idea was considered too risky for routine carrier onboard delivery (COD) operations. Instead, the Grumman C-2 Greyhound was developed as a dedicated COD aircraft. The Hercules used in the test, most recently in service with Marine Aerial Refueler Squadron 352 (VMGR-352) until 2005, is now part of the collection of the National Museum of Naval Aviation at NAS Pensacola,

Deepwater Horizon Oil Spill.

For almost two decades, the wing's 757th Airlift Squadron and the U.S. Coast Guard have participated in oil spill cleanup exercises to ensure the U.S. military has a capable response in the event of a national emergency. The 910th Airlift Wings 757th AS, DOD's only fixed Aerial Spray System certified by the EPA to disperse pesticides on DOD property spread oil dispersants onto the "Deepwater Horizon" oil spill

Hurricane Harvey (2017).

C-130s temporarily based at Kelly Field conducted mosquito control aerial spray applications over areas of eastern Texas devastated by Hurricane Harvey. This special mission treated more than 2.3 million acres at the direction of Federal Emergency Management Agency (FEMA) and the Texas Department of State Health Services (DSHS) to assist in recovery efforts by helping contain the significant increase in pest insects caused by large

Aerial Firefighting.

In the early 1970s Congress created the Modular Airborne FireFighting System (MAFFS) which is a joint operation between The U.S. Forest Service who supply the systems and the Department of Defense who supply the C-130 aircraft. The roll-on/roll-off systems allow existing aircraft to be temporarily converted into a 3,000-gallon airtanker for fighting wildfires when demand exceeds the supply of privately contracted and publicly available airtankers.  In the late 1980s, 22 retired USAF C-130As were removed from storage and transferred to the U.S. Forest Service, which then transferred them to six private companies to be converted into air tankers. One of these C-130s crashed in June 2002 while operating the Retardant Aerial Delivery

Variants.

Significant military variants

Operators.

Former

Accidents.

The C-130 Hercules has had a low accident rate in general. The Royal Air Force recorded an accident rate of about one aircraft loss per 250,000 flying hours over the last 40 years, placing it behind Vickers VC10s and Lockheed TriStars with no flying losses. USAF C-130A/B/E-models had an overall attrition rate of 5% as of

References.

Notes Citations Bibliography

The Lockheed C-130 Hercules is an American four-engine turboprop military transport aircraft designed and built originally by Lockheed (now Lockheed Martin). Capable of using unprepared runways for takeoffs and landings, the C-130 was originally designed as a troop, medevac, and cargo transport aircraft. The versatile airframe has found uses in a variety of other roles, including as a gunship (AC-130), for airborne assault, search and rescue, scientific research support, weather reconnaissance, aerial refueling, maritime patrol, and aerial firefighting. It is now the main tactical airlifter for many military forces worldwide. More than 40 variants of the Hercules, including civilian versions marketed as the Lockheed L-100, operate in more than 60 nations.

Le Lockheed C-130 "Hercules" est un avion de transport militaire conçu par les États-Unis au début des années 1950. Il a rencontré un succès remarquable avec plus de construits pour une cinquantaine de pays utilisateurs, et reste en 2019 encore largement utilisé, et toujours produit dans des versions améliorées.


Development.

The original design introduced numerous novel features never before combined in a handgun: double-action mechanism (without safety); a gas-bleed delayed-blowback system; fixed barrel (that theoretically yields greater accuracy); polygonal rifling; and a reduced number of working parts.  To this list the Rogak variant added newly-fashionable stainless steel construction.  Despite an impressive list of innovative features—or because of it—the Steyr design did not prosper in the United States any better than in its country of origin.

Reception.

Steyr's expectations of an Austrian military contract were upset with the victory of the Glock 17, which won military trials despite the novelty of its extensive employment of large high-strength polymer components, while the 1983 US military pistol competition, in which the Steyr GB competed, was won by the Beretta M92F. Consequently, Steyr decided to re-focus on the police and civilian market.  While much appreciated by users trained and familiar with the weapon, and well received by customers who understood the mechanism, which was intended to result in a robust, accurate, reliable, and functional weapon when used with standard military (full metal jacket) ammunition, the anticipated civilian sales remained low while major official (police) sales never materialized: between the American military's selection of the Beretta 92F, coupled with European military and police forces' selection of the competing SIG-Sauer (P226 full-size and P228 compact high-capacity pistols—the latter adopted by the US Army as the M11) led to a cessation of manufacture of the Steyr GB in 1988 after a total production of between 15,000 and 20,000 pistols—most of them commercial models.  937 of the military models were exported to the United States.

Operating mechanism.

The Steyr GB is a semi-automatic, blowback-operated firearm. It features a unique gas-delayed blowback system based on the Barnitzke system, first used in the Volkssturmgewehr 1-5, and subsequently in the Swiss Pistole 47 W+F (Waffenfabrik Bern) prototype pistol. The Barnitzke system uses gas pressure from the ignited cartridge and feeds it through a small port in the barrel in front of the chamber to retard the rearward motion of the slide.  This is accomplished by using the fixed piston formed by the outside of the barrel, inside a moving cylinder formed by the inside of the slide, gas pressure in the space between them opposing the rearward motion of the slide until the gas pressure has declined (at which point the bullet has left the muzzle) thereby allowing the slide to continue its rearward motion.  Thereafter the Steyr GB follows the conventional semiautomatic cycle: opening the breech; ejecting the empty cartridge case; stripping a new round from the magazine; loading a new cartridge; returning to battery (unless the magazine is empty).

The Steyr GB, is a double-action 9×19mm Parabellum caliber, large-framed semi-automatic pistol employing a gas-delayed blowback action. As such the GB abbreviation stand for "Gasbremse" (gas brake). It was designed in 1968, intended as a replacement for older handguns in Austrian military service.

Le Steyr GB est un pistolet semi-automatique double action autrichien développé à la suite de la décision de l'armée autrichienne de remplacer le Walther P38 et le Browning GP35 dont elle était encore équipée au début des années 1970. La conception du steyr GB fut achevée en 1974 sous la désignation de Pi-18, tirant en rafale, mais ne fut mis en production qu'en 1981.