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The font in St Andrew 's Church , South Croydon |
Out of Great Tribulation ; memorial chapel , Norbury Medthodist church , 1948 |
I Am Among You As He That Serveth ; stained glass window design , St. Edmund 's , Pitlake , 1962 |
= Gambia women 's national football team = |
The Gambia women 's national football team represents the Gambia in international football competition . The team , however , has not competed in a match recognised by FIFA , the sport 's international governing body , despite that organised women 's football has been played in the country since 1998 . The Gambia has t... |
= = The team = = |
In 1985 , few countries had women 's national football teams . While the sport gained popularity worldwide in later decades , the Gambia 's national team only played its first game in 2007 . That game was not FIFA @-@ recognised . As of March 2012 , the team was unranked by FIFA , and as of the following month the Gamb... |
The country did not have a FIFA @-@ recognised youth national team until 2012 , when the Gambia under @-@ 17 women 's team competed in Confederation of African Football qualifiers for the FIFA U @-@ 17 World Cup , to be held in Azerbaijan in September 2012 . The Gambia had fielded an under @-@ 17 team of 24 players , n... |
The Gambia also has an under @-@ 19 team that was to play in the African Women 's U @-@ 19 Championship in 2002 . The Gambia 's first match was against Morocco , but the team withdrew from the competition . |
= = Background and development = = |
The development of women 's football in Africa faces several challenges , including limited access to education , poverty amongst women , inequalities and human rights abuses targeting women . Funding is another issue impacting the game in Africa , where most financial assistance comes from FIFA and not national footba... |
Gambia 's national football association was founded in 1952 , and became affiliated with FIFA in 1968 . Football is the most popular women 's sport in the country , and was first played in an organized system in 1998 . A national competition was launched in 2007 , the same year FIFA started an education course on footb... |
= Plain maskray = |
The plain maskray or brown stingray ( Neotrygon annotata ) is a species of stingray in the family Dasyatidae . It is found in shallow , soft @-@ bottomed habitats off northern Australia . Reaching 24 cm ( 9 @.@ 4 in ) in width , this species has a diamond @-@ shaped , grayish green pectoral fin disc . Its short , whip ... |
Benthic in nature , the plain maskray feeds mainly on caridean shrimp and polychaete worms , and to a lesser extent on small bony fishes . It is viviparous , with females producing litters of one or two young that are nourished during gestation via histotroph ( " uterine milk " ) . This species lacks economic value but... |
= = Taxonomy and phylogeny = = |
The first scientific description of the plain maskray was authored by Commonwealth Scientific and Industrial Research Organisation ( CSIRO ) researcher Peter Last in a 1987 issue of Memoirs of the National Museum of Victoria . The specific name annotatus comes from the Latin an ( " not " ) and notatus ( " marked " ) , ... |
In a 2012 phylogenetic analysis based on mitochondrial and nuclear DNA , the plain maskray and the Ningaloo maskray ( N. ningalooensis ) were found to be the most basal members of Neotrygon . The divergence of the N. annotata lineage was estimated to have occurred ~ 54 Ma . Furthermore , the individuals sequenced in th... |
= = Description = = |
The pectoral fin disc of the plain maskray is thin and diamond @-@ shaped with narrowly rounded outer corners , measuring 1 @.@ 1 – 1 @.@ 3 times longer than wide . The leading margins of the disc are gently concave and converge at a broad angle to the pointed tip of the snout . The small eyes are placed close together... |
The tail is short , barely exceeding the length of the disc when intact , and has a broad and flattened base leading to usually two stinging spines . After the stings , the tail becomes slender and bears a long ventral fin fold and a much shorter , lower dorsal fin fold . Most of the body lacks dermal denticles ; a mid... |
= = Original design = = |
The Type 1 gold dollar depicts a head of Liberty , facing left , with a coronet or tiara on her head bearing her name . Her hair is gathered in a bun ; she is surrounded by 13 stars representing the original states . The reverse features the date and denomination within a wreath , with the name of the nation near the r... |
Contemporary reviews of the Type 1 design were generally favorable . The New York Weekly Tribune on May 19 , 1849 described the new dollar as " undoubtedly the neatest , tiniest , lightest , coin in this country ... it is too delicate and beautiful to pay out for potatoes , and sauerkraut , and salt pork . Oberon might... |
= = Modifications = = |
Mint records indicate the first gold dollars were produced on May 7 , 1849 ; Longacre 's diary notes state instead that the first were struck on May 8 . A few coins in proof condition were struck on the first day , along with about 1 @,@ 000 for circulation . There are five major varieties of the 1849 gold dollar from ... |
The continued flow of gold from California made silver expensive in terms of gold , and U.S. silver coins began to flow out of the country for melting in 1849 , a flow that accelerated over the next several years as the price of the metal continued to rise . By 1853 , a thousand dollars in silver coin contained $ 1 @,@... |
As early as 1851 , New York Congressman William Duer alleged that that Patterson had made the gold dollar too small in diameter on purpose to provoke criticism . Patterson retired that year after 16 years in his position , and under his successor , George N. Eckert , annular gold dollar and half dollar patterns were st... |
The Act of February 21 , 1853 , that had lightened the silver coins also authorized a gold three @-@ dollar piece , which began to be produced in 1854 . To ensure that the three @-@ dollar piece was not mistaken for other gold coins , it had been made thinner and wider than it would normally be , and Longacre put a dis... |
Nevertheless , the Type 2 gold dollar ( as it came to be known ) proved unsatisfactory as the mints had difficulty in striking the new coin so that all details were brought out . This was due to the high relief of the design — the three Southern branch mints especially had trouble with the piece . Many of the Type 2 pi... |
= = = Design of Type 2 and 3 dollars = = = |
The Type 2 and 3 gold dollars depict Liberty as a Native American princess , with a fanciful feathered headdress not resembling any worn by any Indian tribe . This image is an inexact copy of the design Longacre had made for the three @-@ dollar piece , and is one of a number of versions of Liberty Longacre created bas... |
Art historian Cornelius Vermeule deprecated the Indian princess design used by Longacre for the obverses of the Types 2 and 3 gold dollar , and for the three @-@ dollar piece , " the ' princess ' of the gold coins is a banknote engraver 's elegant version of folk art of the 1850s . The plumes or feathers are more like ... |
= = War years = = |
The gold dollar continued to be produced in the late 1850s , though mintages declined from the figures of two million or more each year between 1850 and 1854 . Only about 51 @,@ 000 gold dollars were produced in 1860 , with over two @-@ thirds of that figure at Philadelphia , just under a third at San Francisco , and 1... |
The other candidate for the rarest from that mint is the 1861 @-@ D , with an estimated mintage of 1 @,@ 000 and perhaps 45 to 60 known . Two pairs of dies were shipped from Philadelphia to Dahlonega on December 10 , 1860 ; they arrived on January 7 , 1861 , two weeks before Georgia voted to secede from the Union , as ... |
Dahlonega , like the other two branch mints in the South , closed its doors after the 1861 strikings . It and the Charlotte facility never reopened ; the New Orleans Mint again struck coins from 1879 to 1909 , but did not strike gold dollars again . After 1861 , the only issuance of gold dollars outside Philadelphia wa... |
The outbreak of the Civil War shook public confidence in the Union , and citizens began hoarding specie , gold and silver coins . In late December 1861 , banks and then the federal Treasury stopped paying out gold at face value . By mid @-@ 1862 , all federal coins , even the base metal cent , had vanished from commerc... |
= = Final years , abolition , and collecting = = |
Since gold did not circulate in the United States ( except on the West Coast ) in the postwar period , much of the production of coins of that metal in the United States was double eagles for export . Accordingly , although 1 @,@ 361 @,@ 355 gold dollars were struck in 1862 — the last time production would exceed a mil... |
In the 1870s and 1880s , public interest grew in the low @-@ mintage gold dollar . Collecting coins was becoming more popular , and a number of numismatists put aside some gold dollars and hoped for increases in value . The Mint most likely channeled its production through some favored Philadelphia dealers , though pro... |
James Pollock , in his final report as Mint Director in 1873 , advocated limiting striking of gold dollars to depositors who specifically requested it . " The gold dollar is not a convenient coin , on account of its small size , and it suffers more proportionately from abrasion than larger coins . " His successors call... |
A total of 19 @,@ 499 @,@ 337 gold dollars were coined , of which 18 @,@ 223 @,@ 438 were struck at Philadelphia , 1 @,@ 004 @,@ 000 at New Orleans , 109 @,@ 138 at Charlotte , 90 @,@ 232 at San Francisco and 72 @,@ 529 at Dahlonega . According to an advertisement in the February 1899 issue of The Numismatist , gold do... |
= = Commemorative gold dollars = = |
The gold dollar had a brief resurrection during the period of Early United States commemorative coins . Between 1903 and 1922 nine different issues were produced , with a total mintage of 99 @,@ 799 . These were minted for various public events , did not circulate , and none used Longacre 's design . |
= Johnson – Corey – Chaykovsky reaction = |
The Johnson – Corey – Chaykovsky reaction ( sometimes referred to as the Corey – Chaykovsky reaction or CCR ) is a chemical reaction used in organic chemistry for the synthesis of epoxides , aziridines , and cyclopropanes . It was discovered in 1961 by A. William Johnson and developed significantly by E. J. Corey and M... |
The reaction is most often employed for epoxidation via methylene transfer , and to this end has been used in several notable total syntheses ( See Synthesis of epoxides below ) . Additionally detailed below are the history , mechanism , scope , and enantioselective variants of the reaction . Several reviews have been ... |
= = History = = |
The original publication by Johnson concerned the reaction of 9 @-@ dimethylsulfonium fluorenylide with substituted benzaldehyde derivatives . The attempted Wittig @-@ like reaction failed and a benzalfluorene oxide was obtained instead , noting that " Reaction between the sulfur ylid and benzaldehydes did not afford b... |
The subsequent development of ( dimethyloxosulfaniumyl ) methanide , ( CH3 ) 2SOCH2 and ( dimethylsulfaniumyl ) methanide , ( CH3 ) 2SCH2 ( known as Corey – Chaykovsky reagents ) by Corey and Chaykovsky as efficient methylene @-@ transfer reagents established the reaction as a part of the organic canon . |
= = Mechanism = = |
The reaction mechanism for the Johnson – Corey – Chaykovsky reaction consists of nucleophilic addition of the ylide to the carbonyl or imine group . A negative charge is transferred to the heteroatom and because the sulfonium cation is a good leaving group it gets expelled forming the ring . In the related Wittig react... |
The trans diastereoselectivity observed results from the reversibility of the initial addition , allowing equilibration to the favored anti betaine over the syn betaine . Initial addition of the ylide results in a betaine with adjacent charges ; density functional theory calculations have shown that the rate @-@ limiti... |
The degree of reversibility in the initial step ( and therefore the diastereoselectivity ) depends on four factors , with greater reversibility corresponding to higher selectivity : |
Stability of the substrate with higher stability leading to greater reversibility by favoring the starting material over the betaine . |
Stability of the ylide with higher stability similarly leading to greater reversibility . |
Steric hindrance in the betaine with greater hindrance leading to greater reversibility by disfavoring formation of the intermediate and slowing the rate @-@ limiting rotation of the central bond . |
Solvation of charges in the betaine by counterions such as lithium with greater solvation allowing more facile rotation in the betaine intermediate , lowering the amount of reversibility . |
= = Scope = = |
The application of the Johnson – Corey – Chaykovsky reaction in organic synthesis is diverse . The reaction has come to encompass reactions of many types of sulfur ylides with electrophiles well beyond the original publications . It has seen use in a number of high @-@ profile total syntheses , as detailed below , and ... |
= = = Types of ylides = = = |
Many types of ylides can be prepared with various functional groups both on the anionic carbon center and on the sulfur . The substitution pattern can influence the ease of preparation for the reagents ( typically from the sulfonium halide , e.g. trimethylsulfonium iodide ) and overall reaction rate in various ways . T... |
Use of a sulfoxonium allows more facile preparation of the reagent using weaker bases as compared to sulfonium ylides . ( The difference being that a sulfoxonium contains a doubly bonded oxygen whereas the sulfonium does not . ) The former react slower due to their increased stability . In addition , the dialkylsulfoxi... |
The vast majority of reagents are monosubstituted at the ylide carbon ( either R1 or R2 as hydrogen ) . Disubstituted reagents are much rarer but have been described : |
If the ylide carbon is substituted with an electron @-@ withdrawing group ( EWG ) , the reagent is referred to as a stabilized ylide . These , similarly to sulfoxonium reagents , react much slower and are typically easier to prepare . These are limited in their usefulness as the reaction can become prohibitively sluggi... |
If the ylide carbon is substituted with an aryl or allyl group , the reagent is referred to as a semi @-@ stabilized ylide . These have been developed extensively , second only to the classical methylene reagents ( R1 = R2 = H ) . The substitution pattern on aryl reagents can heavily influence the selectivity of the re... |
If the ylide carbon is substituted with an alkyl group the reagent is referred to as an unstabilized ylide . The size of the alkyl groups are the major factors in selectivity with these reagents . |
The R @-@ groups on the sulfur , though typically methyls , have been used to synthesize reagents that can perform enantioselective variants of the reaction ( See Variations below ) . The size of the groups can also influence diastereoselectivity in alicyclic substrates . |
= = = Synthesis of epoxides = = = |
Reactions of sulfur ylides with ketones and aldehydes to form epoxides are by far the most common application of the Johnson – Corey – Chaykovsky reaction . Examples involving complex substrates and ' exotic ' ylides have been reported , as shown below . |
The reaction has been used in a number of notable total syntheses including the Danishefsky Taxol total synthesis , which produces the chemotherapeutic drug taxol , and the Kuehne Strychnine total synthesis which produces the pesticide strychnine . |
= = = Synthesis of aziridines = = = |
The synthesis of aziridines from imines is another important application of the Johnson – Corey – Chaykovsky reaction and provides an alternative to amine transfer from oxaziridines . Though less widely applied , the reaction has a similar substrate scope and functional group tolerance to the carbonyl equivalent . The ... |
= = = Synthesis of cyclopropanes = = = |
For addition of sulfur ylides to enones , higher 1 @,@ 4 @-@ selectivity is typically obtained with sulfoxonium reagents than with sulfonium reagents . Many electron @-@ withdrawing groups have been shown compatible with the reaction including ketones , esters , and amides ( the example below involves a Weinreb amide )... |
= = = Other reactions = = = |
In addition to the reactions originally reported by Johnson , Corey , and Chaykovsky , sulfur ylides have been used for a number of related homologation reactions that tend to be grouped under the same name . |
With epoxides and aziridines the reaction serves as a ring @-@ expansion to produce the corresponding oxetane or azetidine . The long reaction times required for these reactions prevent them from occurring as significant side reactions when synthesizing epoxides and aziridines . |
Several cycloadditions wherein the ylide serves as a " nucleophilic carbenoid equivalent " have been reported . |
Living polymerizations using trialkylboranes as the catalyst and ( dimethyloxosulfaniumyl ) methanide as the monomer have been reported for the synthesis of various complex polymers . |
= = Enantioselective variations = = |
The development of an enantioselective ( i.e. yielding an enantiomeric excess , which is labelled as " ee " ) variant of the Johnson – Corey – Chaykovsky reaction remains an active area of academic research . The use of chiral sulfides in a stoichiometric fashion has proved more successful than the corresponding cataly... |
= = = Stoichiometric reagents = = = |
The most successful reagents employed in a stoichiometric fashion are shown below . The first is a bicyclic oxathiane that has been employed in the synthesis of the β @-@ adrenergic compound dichloroisoproterenol ( DCI ) but is limited by the availability of only one enantiomer of the reagent . The synthesis of the axi... |
The other major reagent is a camphor @-@ derived reagent developed by Varinder Aggarwal of the University of Bristol . Both enantiomers are easily synthesized , although the yields are lower than for the oxathiane reagent . The ylide conformation is determined by interaction with the bridgehead hydrogens and approach o... |
= = = Catalytic reagents = = = |
Catalytic reagents have been less successful , with most variations suffering from poor yield , poor enantioselectivity , or both . There are also issues with substrate scope , most having limitations with methylene transfer and aliphatic aldehydes . The trouble stems from the need for a nucleophilic sulfide that effic... |
Aggarwal has developed an alternative method employing the same sulfide as above and a novel alkylation involving a rhodium carbenoid formed in situ . The method too has limited substrate scope , failing for any electrophiles possessing basic substituents due to competitive consumption of the carbenoid . |
= Treaty of Ciudad Juárez = |
The Treaty of Ciudad Juárez was a peace treaty signed between the then President of Mexico , Porfirio Díaz , and the revolutionary Francisco Madero on May 21 , 1911 . The treaty put an end to the fighting between forces supporting Madero and those of Díaz and thus concluded the initial phase of the Mexican Revolution . |
The treaty stipulated that Díaz , as well as his vice president Ramón Corral , were to step down by the end of May , and that he was to be replaced by Francisco León de la Barra as interim president and hold presidential elections . Those who had suffered losses due to the revolution would be the indemnified , and ther... |
Significantly , the treaty did not mention or institute any social reforms that Madero had vaguely promised on previous occasions . It also left the Porfirian state essentially intact . Additionally , Madero supported the unpopular idea that all land disputes were to be settled through the courts , staffed by the old j... |
On June 7 , 1911 , Madero entered Mexico City . In October 1911 he was elected president , under the banner of the Partido Constitucional Progresista , along with José María Pino Suárez , his new running mate as vice @-@ president . Madero pushed aside Francisco Vázquez Gómez , the vice presidential candidate for the A... |
= = Military developments leading up to the treaty = = |
The rebellion against the government of Porfirio Díaz broke out in late 1910 , after Díaz had his rival Francisco Madero imprisoned and had announced his own victory in a falsified election . Madero 's earlier vague promises of agrarian reforms had attracted many supporters . He himself escaped from prison and fled to ... |
In the Guerrero district of Chihuahua , Pascual Orozco attacked Federal troops and sent dead soldiers ' clothing back to Díaz with the message , " Ahí te van las hojas , mándame más tamales " ( " Here are the wrappers , send me more tamales . " ) He then began operations which threatened Ciudad Juárez . Additionally , ... |
At roughly the same time , agrarian unrest in the state of Morelos turned into a full blown rebellion under the leadership of the Zapata brothers , Emiliano and Eufemio . |
= = = Orozco and Villa take Ciudad Juárez = = = |
Encouraged by the news of the uprisings , Madero crossed the border back into Mexico in February 1911 . He was joined by Pancho Villa and Orozco and in April the army began approaching Ciudad Juárez . Orozco and Villa led the way with 500 men each , while Madero followed up with 1 @,@ 500 riders . The city was besieged... |
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