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Common carp

The common carp or European carp is a widespread freshwater fish of eutrophic waters in lakes and large rivers in Europe and Asia. The native wild populations are considered vulnerable to extinction by the International Union for Conservation of Nature, but the species has been domesticated and introduced into environments worldwide, is considered a destructive invasive species, being included in the list of the world's 100 worst invasive species, it gives its name to Cyprinidae. The two subspecies are: C. c. carpio is native to much of Europe. C. c. yilmaz is from Anatolian Turkey. A third subspecies, C. c. haematopterus native to eastern Asia, was recognized in the past, but recent authorities treat it as a separate species under the name C. rubrofuscus. The common carp and various Asian relatives in the pure forms can be separated by meristics and differ in genetics, but they are able to interbreed. Common carp can interbreed with the goldfish; the common carp is native to Europe and Asia, has been introduced to every part of the world except the poles.

They are the third most introduced species worldwide, their history as a farmed fish dates back to Roman times. Carp are used as food in many areas, but are regarded as a pest in several regions due to their ability to out-compete native fish stocks; the original common carp was found in the inland delta of the Danube River about 2000 years ago, was torpedo-shaped and golden-yellow in colour. It had two pairs of a mesh-like scale pattern. Although this fish was kept as an exploited captive, it was maintained in large, specially built ponds by the Romans in south-central Europe; as aquaculture became a profitable branch of agriculture, efforts were made to farm the animals, the culture systems soon included spawning and growing ponds. The common carp's native range extends to the Black Sea, Caspian Sea and Aral Sea. Both European and Asian subspecies have been domesticated. In Europe, domestication of carp as food fish was spread by monks between the 13th and 16th centuries; the wild forms of carp had reached the delta of the Rhine in the 12th century with some human help.

Variants that have arisen with domestication include the mirror carp, with large, mirror-like scales, the leather carp, the scaled carp. Koi carp is a domesticated ornamental variety that originated in the Niigata region of Japan in the 1820s, but its parent species are the East Asian carp C. rubrofuscus. Wild common carp are slimmer than domesticated forms, with body length about four times body height, red flesh, a forward-protruding mouth. Common carp can grow to large sizes if given adequate space and nutrients, their average growth rate by weight is about half the growth rate of domesticated carp They do not reach the lengths and weights of domesticated carp, which can grow to a maximum length of 120 centimetres, a maximum weight of over 40 kilograms, an oldest recorded age of 38 years. The largest recorded carp, caught by an angler in January 2010 at Lac de curtons near Bordeaux, weighed 42.6 kilograms. The largest recorded carp, caught by British angler, Colin Smith, in 2013 at Etang La Saussaie Fishery, weighed 45.59 kilograms.

The average size of the common carp is around 40 -- 2 -- 14 kg. Although tolerant of most conditions, common carp prefer large bodies of slow or standing water and soft, vegetative sediments; as schooling fish, they prefer to be in groups of five or more. They live in temperate climates in fresh or brackish water with a pH of 6.5–9.0 and salinity up to about 0.5%, temperatures of 3 to 35 °C. The ideal temperature is 23 to 30 °C, with spawning beginning at 17 to 18 °C. Carp are able to tolerate water with low oxygen levels, by gulping air at the surface. Common carp are omnivorous, they can eat a herbivorous diet of aquatic plants, but prefer to scavenge the bottom for insects, crustaceans and benthic worms. An egg-layer, a typical adult female can lay 300,000 eggs in a single spawn. Although carp spawn in the spring, in response to rising water temperatures and rainfall, carp can spawn multiple times in a season. In commercial operations, spawning is stimulated using a process called hypophysation, where lyophilized pituitary extract is injected into the fish.

The pituitary extract contains gonadotropic hormones which stimulate gonad maturation and sex steroid production promoting reproduction. A single carp can lay over a million eggs in a year, yet their population remains the same, so the eggs and young perish in vast numbers. Eggs and fry fall victim to bacteria and the vast array of tiny predators in the pond environment. Carp which survive to juvenile are preyed upon by other fish such as the northern pike and largemouth bass, a number of birds and mammals. Common carp have been introduced to most continen

Orbia

Orbia is a Mexican company involved in several industries, including building and infrastructure, data communications, irrigation and more. It has operations in 41 countries, with more than 22,000 employees. Mexichem has annual revenues of US$7.2 billion and has been traded on the Mexican Stock Exchange for more than 30 years. The company is a member of the Mexican Stock Exchange Sustainability Index and the FTSE4Good Sustainability Emerging Markets index. Headquarters are located in Ciudad de Mexico. On August 7, 2017, Mexichem SA announced it would acquire the Israeli irrigation company Netafim from Permira Holdings Ltd. for $1.5 billion. On September 4, 2019, Mexichem, S. A. B. de C. V. announced. In addition, its sector classification on the Mexican Stock Exchange changed from "Materials" to "Industrials". Www.orbia.com Mexichem on the Forbes Global 2000 List

Council of Constantinople (861)

The Council of Constantinople of 861 known as Protodeutera, was a major Church Council, convened upon the initiative of Emperor Michael III of Byzantium and Patriarch Photios I of Constantinople, attended by legates of Pope Nicholas I. The Council confirmed the deposition of former Patriarch Ignatius of Constantinople, his replacement by Photios. Several dogmatic and liturgical questions were discussed, seventeen canons were produced. Decisions of the Council were approved by papal legates, but their approval was annulled by the Pope. In spite of that, the Council is considered as valid by the Eastern Orthodox Church. In 860, Byzantine Emperor Michael III and Patriarch Photios I of Constantinople decided to convene a major church council in order to resolve several doctrinal and liturgical questions, they approached Pope Nicholas I. Papal legates, bishops Radoald of Porto and Zachary of Anagni, were well-received in Constantinople, soon upon their arrival the Council was convened in the spring of 861.

Among major issues discussed at the Council, the most significant were various questions regarding earlier deposition of former Patriarch Ignatius of Constantinople, in connection with that the questions regarding canonical validity of appointment and speedy promotion of his successor, Patriarch Photios. After extensive deliberation, the Council confirmed the validity of earlier deposition of Ignatius and election of Photios; such conclusions were approved by papal legates at the Council, but their approval was annulled by the Pope. Schism of 863 Council of Constantinople Dvornik, Francis; the Photian Schism: History and Legend. Cambridge, UK: Cambridge University Press. Ostrogorsky, George. History of the Byzantine State. Oxford: Basil Blackwell. Thomas, John P.. Private Religious Foundations in the Byzantine Empire. Washington, D. C.: Dumbarton Oaks. Canons of the Council of Constantinople