Chengdu, alternatively romanized as Chengtu, is a sub-provincial city which serves as the capital of the Chinese province of Sichuan. It is one of the three most-populous cities in Western China, the other two being Chongqing and Xi'an; as of 2014, the administrative area housed 14,427,500 inhabitants, the largest in Sichuan, with an urban population of 10,152,632. At the time of the 2010 census, Chengdu was the fifth-most populous agglomeration in China, with 10,484,996 inhabitants in the built-up area including Xinjin County and Deyang's Guanghan City. Chengdu is considered a World City with a "Beta +" classification, according to the Globalization and World Cities Research Network. Chengdu is located in central Sichuan; the surrounding Chengdu Plain is known as the "Country of Heaven" and the "Land of Abundance". Its prehistoric settlers included the Sanxingdui culture; the site of Dujiangyan, an ancient irrigation system, is designated as a World Heritage Site. The Jin River flows through the city.
Founded by the state of Shu prior to its incorporation into China, Chengdu is unique as a major Chinese settlement that has maintained its name unchanged throughout the imperial and communist eras. It was the capital of Liu Bei's Shu Han during the Three Kingdoms Era, as well as several other local kingdoms during the Middle Ages. During World War II, refugees from eastern China fleeing from the Japanese settled in Chengdu. After the war, Chengdu's importance as a link between Eastern and Western China expanded, with railways built to Chongqing in 1952, Kunming and Tibet afterwards. In the 1960s, Chengdu became an important centre of China's national defense industry. Chengdu is now one of the most important economic, commercial, cultural and communication centers in Western China, its economy is diverse, characterized by the machinery, medicine and information technology industries. Chengdu Shuangliu International Airport, a hub of Air China and Sichuan Airlines, is one of the 30 busiest airports in the world, the Chengdu railway station is one of the six biggest in China.
Chengdu hosts many international companies and more than 12 consulates. Chengdu is the seat of the Western Theatre Command region of the People's Liberation Army. Chengdu will host the FISU Summer World University Games in 2021, an international multi-sport event, it is considered one of the most livable cities in China. Chengdu's culture reflects that of its province, Sichuan, it is associated with the giant panda, a Chinese national symbol, which inhabits the area of Sichuan. The name Chengdu is attested in sources dating back to the Warring States period, it has been called the only major city in China to have remained at an unchanged location with an unchanged name throughout the imperial and communist eras, although it had other names, for example it was known as "Xijing" in the 17th century. Etymology of the name is unclear; the earliest and most known explanation, although not accepted by modern schlars, is provided in the 10th-century geographical work Universal Geography of the Taiping Era, which states that the ninth king of Shu's Kaiming dynasty named his new capital Chengdu after a statement by King Tai of Zhou that a settlement needed "one year to become a town, two to become a city, three to become a metropolis".
The present spelling is based on pinyin romanization. Its former status as the seat of the Chengdu Prefecture prompted Marco Polo's spellings "Sindafu", "Sin-din-fu", &c. and the Protestant missionaries' romanization "Ching-too Foo". Although the official name of the city has remained constant, the surrounding area has sometimes taken other names, including "Yizhou". Chinese nicknames for the city include the "Turtle City", variously derived from the old city walls' shape on a map or a legend that Zhang Yi had planned their course by following a turtle's tracks; the city logo adopted in 2011 is inspired by the Golden Sun Bird, an ancient artifact unearthed in 2001 from the Jinsha Ruins. Archaeological discoveries at the Sanxingdui and Jinsha sites have established that the area surrounding Chengdu was inhabited over four thousand years ago, in 18–10th century BC. At the time of China's Xia and Zhou dynasties, it represented a separate ancient bronze-wielding culture which—following its partial sinification—became known to the Chinese as Shu.
Shu was conquered by Qin in the settlement re-founded by the Qin general Zhang Yi. Although he had argued against the invasion, the settlement thrived and the additional resources from Sichuan helped enable the First Emperor of Qin to unify the Warring States which had succeeded the Zhou. Under the Han, the brocade produced in Chengdu was exported throughout China. A "Brocade Official" was established to oversee its supply. After the fall of the Eastern Han, Liu Bei ruled Shu, t
An oocyte, oöcyte, ovocyte, or ocyte, is a female gametocyte or germ cell involved in reproduction. In other words, it is egg cell. An oocyte is produced in the ovary during female gametogenesis; the female germ cells produce a primordial germ cell, which undergoes mitosis, forming oogonia. During oogenesis, the oogonia become primary oocytes. An oocyte is a form of genetic material. Cryoconservation of animal genetic resources has been put into action as a means of conserving traditional livestock; the formation of an oocyte is called oocytogenesis, a part of oogenesis. Oogenesis results in the formation of both primary oocytes during fetal period, of secondary oocytes after it as part of ovulation. Oocytes are rich in cytoplasm, which contains yolk granules to nourish the cell early in development. During the primary oocyte stage of oogenesis, the nucleus is called a germinal vesicle; the only normal human type of secondary oocyte has the 23rd chromosome as 23,X, whereas sperm can have 23,X or 23,Y.
The space within an ovum or immature ovum is located. The cumulus-oocyte complex contains layers of packed cumulus cells surrounding the oocyte in the Graafian follicle; the oocyte is arrested in Meiosis II at the stage of metaphase II and is considered a secondary oocyte. Before ovulation, the cumulus complex goes through a structural change known as cumulus expansion; the granulosa cells transform from compacted to an expanded mucoid matrix. Many studies show that cumulus expansion is critical for the maturation of the oocyte because the cumulus complex is the oocyte’s direct communication with the developing follicle environment, it plays a significant role in fertilization, though the mechanisms are not known and are species specific. Because the fate of an oocyte is to become fertilized and grow into a functioning organism, it must be ready to regulate multiple cellular and developmental processes; the oocyte, a large and complex cell, must be supplied with numerous molecules that will direct the growth of the embryo and control cellular activities.
As the oocyte is a product of female gametogenesis, the maternal contribution to the oocyte and the newly fertilized egg, is enormous. There are many types of molecules that are maternally supplied to the oocyte, which will direct various activities within the growing zygote; the DNA of a cell is vulnerable to the damaging effect of oxidative free radicals produced as byproducts of cellular metabolism. DNA damage occurring in oocytes, if not repaired, can be lethal and result in reduced fecundity and loss of potential progeny. Oocytes are larger than the average somatic cell, thus considerable metabolic activity is necessary for their provisioning. If this metabolic activity were carried out by the oocyte’s own metabolic machinery, the oocyte genome would be exposed to the reactive oxidative by-products generated, thus it appears that a process evolved to avoid this vulnerability of germ line DNA. It was proposed that, in order to avoid damage to the DNA genome of the oocytes, the metabolism contributing to the synthesis of much of the oocyte’s constituents was shifted to other maternal cells that transferred these constituents to oocytes.
Thus, oocytes of many organisms are protected from oxidative DNA damage while storing up a large mass of substances to nurture the zygote in its initial embryonic growth. During the growth of the oocyte, a variety of maternally transcribed messenger RNAs, or mRNAs, are supplied by maternal cells; these mRNAs can be stored in mRNP complexes and be translated at specific time points, they can be localized within a specific region of the cytoplasm, or they can be homogeneously dispersed within the cytoplasm of the entire oocyte. Maternally loaded proteins can be localized or ubiquitous throughout the cytoplasm; the translated products of the mRNAs and the loaded proteins have multiple functions. Below are some examples of maternally inherited mRNAs and proteins found in the oocytes of the African clawed frog; the oocyte receives mitochondria from maternal cells, which will go on to control embryonic metabolism and apoptotic events. The partitioning of mitochondria is carried out by a system of microtubules that will localize mitochondria throughout the oocyte.
In certain organisms, such as mammals, paternal mitochondria brought to the oocyte by the spermatozoon are degraded through the attachment of ubiquitinated proteins. The destruction of paternal mitochondria ensures the maternal inheritance of mitochondria and mitochondrial DNA or mtDNA. In mammals, the nucleolus of the oocyte is derived from maternal cells; the nucleolus, a structure found within the nucleus, is the location where rRNA is transcribed and assembled into ribosomes. While the nucleolus is dense and inactive in a mature oocyte, it is required for proper development of the embryo. Maternal cells synthesize and contribute a store of ribosomes that are required for the translation of proteins before the zygotic genome is activated. In mammalian oocytes, maternally derived ribosomes and some mRNAs are stored in a structure called cytoplasmic lattices; these cytoplasmic lattices, a network of fibrils, RNAs, have been observed to increase in density as the number of ribosomes decrease within a growing oocyte.
The spermatozoon that fertilizes an oocyte will contribute its pronucle
The Cross was an English rock band formed in 1987 by Queen drummer Roger Taylor. They released three studio albums before splitting up in 1993. Unlike in Queen, Taylor played rhythm guitar. On their debut album, recorded by Taylor before recruiting the rest of the band, they incorporated dance influences which were dropped on subsequent albums. Taylor formed the Cross while Queen were on break after the Magic Tour in 1986, he advertised for the remaining musicians. When the band was formed, guitarist Clayton Moss, bassist Peter Noone, drummer Josh Macrae; the band's albums and singles were not commercially successful, although they did manage to reach the British charts with several and they enjoyed moderate success in Germany. The first album, Shove It, was released on Virgin Records in 1987. A solo project for Taylor, who had written the songs prior to forming the band, the album and the three singles it spawned did reach the charts in the UK, where it received some positive press; the band toured in support of the album before Taylor took a short break for the 1989 Queen album The Miracle, for which there was no tour.
After Queen's 1986 Magic Tour, the band members went their separate ways to do various solo work. Taylor decided to form a new band with, he had written and recorded the album himself before finding a band to play the songs with. He placed an ad for band members in a national newspaper, hinting he was a famous rock musician; the position of keyboard player was duly offered to Spike Edney after two successful Queen tours with him handling the keys. When the auditions were over, the line-up was completed by Peter Noone on bass, Clayton Moss on guitar, Josh Macrae on drums; the first album, Shove It, was released in 1987. Two tracks featured fellow Queen band members: the track "Heaven for Everyone" featured vocals by Freddie Mercury, while "Love Lies Bleeding" featured Brian May on guitar; the European CD contained an extra track in The 2nd Shelf Mix, the US version having "Feel The Force" as its extra track. The band promoted hard in Germany with many TV performances of singles including an appearance at the Montreux Golden Rose festival in 1988.
The tour took in dates in the Germany. Three singles were released from the album: "Cowboys and Indians", "Heaven for Everyone" and "Shove It". Another single, "Manipulator," was released in 1988, it was the only song from the time that had joint writing credits, Taylor sharing them with Spike Edney and Steve Strange. The second single from Shove It, "Heaven for Everyone", would be re-released by the remaining members of Queen, using Freddie Mercury's lead vocal take from the Shove It sessions, it was released as the lead single from the 1995 album Made in Heaven and went on to become a major hit in several countries. After finishing Queen's 1989 album The Miracle, Taylor went into the studio with the rest of the Cross for the first time to record Mad and Dangerous to Know; the band composed the opening track "Top Of The World Ma". The rest of the album consisted of individually written songs, except for "Power To Love", a joint venture by Macrae and Moss. Clayton Moss sang lead vocals on his own track "Better Things", Spike Edney played mandolin on "Final Destination", written by Taylor.
"Final Destination" was released as a single, as were "Liar" and "Power To Love", the latter being the last single to be released in the UK by the group. "Final Destination" came with a live rendition of Taylor's song "Man On Fire" as a B-side, "Liar" had a brand new track, "In Charge Of My Heart", penned by Taylor. The 12" single and CD of "Liar" included extended remixes of both "Liar" and "In Charge Of My Heart"; the instrumental section at the beginning of "In Charge Of My Heart" was used as the opening to concerts on the accompanying tour. "Closer To You" had been planned to be released in America, but the idea was never discussed again. The group having given up on the UK market, the accompanying tour only included dates in Germany, Austria and Ibiza. Unusual for such tours, every song from the new album was played live. Made at a time when Taylor's efforts were concentrated on Queen, Blue Rock gave the other members of the band a chance to take control of the upcoming album, it was written by Edney, who contributed three of his own tracks and contributed to four more.
Once again, the opening track was penned by the entire band, "Bad Attitude" was written by the Christmas fan club party of 1990. Blue Rock was only released in Germany. "New Dark Ages" was released in Germany with another live version of "Man On Fire", whilst "Life Changes" was released with the B-side "Heartland". It was however withdrawn, due to the death of Freddie Mercury; the tour was in support of Magnum, so the concert lengths were short and few bootlegs survived. The tour was rapid month. EMI Records refused to release a third album by the band. However, as the band had enjoyed moderate success in Germany, EMI's German branch EMI Electrola still released their third effort, Blue Rock, in that country; the band broke up in 1993 after performing a final show. Taylor produced solo albums. Drummer Macrae accompanied Taylor on his solo tours and played percussion at The Freddie Mercury Tribute Concert. Both Taylo