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Aachen
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Early history
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Early history
Flint quarries on the Lousberg, Schneeberg, and Königshügel, first used during Neolithic times (3000–2500 BC), attest to the long occupation of the site of Aachen, as do recent finds under the modern city's Elisengarten pointing to a former settlement from the same period. Bronze Age (around 1600 BC) settlement is evidenced by the remains of barrows (burial mounds) found, for example, on the Klausberg. During the Iron Age, the area was settled by Celtic peoples. who were perhaps drawn by the marshy Aachen basin's hot sulphur springs where they worshipped Grannus, god of light and healing.
The 25-hectare Roman spa resort town of Aquae Granni was, according to legend, founded by Grenus, under Hadrian, around 124 AD. Grenus refers to the Celtic god, and it seems it was the Roman 6th Legion at the start of the 1st century AD that first channelled the hot springs into a spa at Büchel, adding at the end of the same century the Münstertherme spa,. two water pipelines, and a probable sanctuary dedicated to Grannus. A kind of forum, surrounded by colonnades, connected the two spa complexes. There was an extensive residential area. The Romans built bathhouses near Burtscheid. A temple precinct called Vernenum was built near the modern Kornelimünster/Walheim. Today, remains have been found of three bathhouses,. including two fountains in the Elisenbrunnen and the Burtscheid bathhouse.
Roman civil administration in Aachen eventually broke down as the baths and other public buildings (along with most of the villae rusticae of the surrounding countryside) were destroyed around AD 375 at the start of the migration period. The last Roman coin finds are from the time of Emperor Gratian (AD 375–383). Rome withdrew its troops from the area, but the town remained populated. By 470, the town came to be ruled by the Ripuarian Franks. and subordinated to their capital, Cologne. During the Roman period, Aachen was the site of a flourishing Jewish community..
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Aachen
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Middle Ages
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Middle Ages
Pepin the Short had a castle residence built in the town, due to the proximity of the hot springs and also for strategic reasons as it is located between the Rhineland and northern France.. Einhard mentions that in 765–766 Pepin spent both Christmas and Easter at Aquis villa (). ("and [he] celebrated the birth of the Lord [Christmas] in the town Aquis, and similarly Easter"), which must have been sufficiently equipped to support the royal household for several months. In the year of his coronation as king of the Franks, 768, Charlemagne came to spend Christmas at Aachen for the first time. He remained there in a mansion which he may have extended, although there is no source attesting to any significant building activity at Aachen in his time, apart from the building of the Palatine Chapel (since 1930, cathedral) and the Palace.
Charlemagne spent most winters in Aachen between 792 and his death in 814. Aachen became the focus of his court and the political centre of his empire. During the Carolingian empire, a Jewish community lived near the royal palace. In Jewish texts, the city of Aachen was called Aish or Ash (אש). In 797, Isaac, a Jewish merchant, accompanied two ambassadors of Charlemagne to the court of Harun al-Rashid. He returned to Aachen in July 802, bearing an elephant called Abul-Abbas as a gift for the emperor. After Charlemagne's death, he was buried in the church which he had built;. his original tomb has been lost, while his alleged remains are preserved in the Karlsschrein, the shrine where he was reburied after being declared a saint; his saintliness, however, was never officially acknowledged by the Roman Curia as such.
thumb|right|Construction of Aix-la-Chapelle, by Jean Fouquet
thumb|150px|Presentation of the four "Great Relics" during the Aachen pilgrimage, after a 17th-century painting
In 936, Otto I was crowned king of East Francia in the collegiate church built by Charlemagne. During the reign of Otto II, the nobles revolted and the West Franks under Lothair. raided Aachen in 978.. Aachen was attacked again by Odo of Champagne, who attacked the imperial palace while Conrad II was absent. Odo relinquished it and was killed afterwards.. The palace and town of Aachen had fortifying walls built by order of Emperor Frederick Barbarossa between 1172 and 1176. Over the next 500 years, most kings of Germany who ruled the Holy Roman Empire were crowned in Aachen. The original audience hall built by Charlemagne was torn down and replaced by the current city hall in 1330. During the 13th century, many Jews converted to Christianity, as shown in the records of the Aachen Minster (today's Cathedral). In 1486, the Jews of Aachen offered gifts to Maximilian I during his coronation ceremony. The last king to be crowned here was Ferdinand I in 1531.
During the Middle Ages, Aachen remained a city of regional importance, due to its proximity to Flanders; it achieved a modest position in the trade in woollen cloths, favoured by imperial privilege. The city remained a free imperial city, subject to the emperor only, but was politically far too weak to influence the policies of any of its neighbours. The only dominion it had was over Burtscheid, a neighbouring territory ruled by a Benedictine abbess, which was forced to accept that all of its traffic must pass through the "Aachener Reich".
As an imperial city, Aachen held certain political privileges that allowed it to remain independent of the troubles of Europe for many years. It remained a direct vassal of the Holy Roman Empire throughout most of the Middle Ages. It was also the site of many important church councils, including the Council of 837 and the Council of 1166, a council convened by the antipope Paschal III.
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Aachen
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Manuscript production
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Manuscript production
Aachen was an important site for the production of historical manuscripts. Under Charlemagne's purview, both the Ada Gospels and the Coronation Gospels may have been produced in Aachen.. In addition, quantities of the other texts in the court library were also produced locally. During the reign of Louis the Pious (814–840), substantial quantities of ancient texts were produced at Aachen, including legal manuscripts such as the leges scriptorium group, patristic texts including the five manuscripts of the Bamberg Pliny Group. Finally, under Lothair I (840–855), texts of outstanding quality were still being produced. This however marked the end of the period of manuscript production at Aachen.
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Aachen
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16th–18th centuries
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16th–18th centuries
thumb|upright=1.2|The siege of Aachen by the Spanish Army of Flanders under Ambrogio Spinola in 1614
thumb|upright=1.2|View of Aachen in 1690
In 1598, following the invasion of Spanish troops from the Netherlands, Rudolf deposed all Protestant office holders in Aachen and went as far as expelling them from the city.. From the early 16th century, Aachen started to lose its power and influence. First the coronations of emperors were moved from Aachen to Frankfurt. This was followed by the religious wars and the great fire of 1656.. After the destruction of most of the city in 1656, the rebuilding was mostly in the Baroque style. The decline of Aachen culminated in 1794, when the French, led by General Charles Dumouriez, occupied Aachen.
In 1542, the Dutch humanist and physician Francis Fabricius published his study of the health benefits of the hot springs in Aachen. By the middle of the 17th century, the city had developed a considerable reputation as a spa, although this was in part because Aachen was then – and remained well into the 19th and early 20th century – a place of high-level prostitution. Traces of this hidden agenda of the city's history are found in the 18th-century guidebooks to Aachen as well as to the other spas.
The main indication for visiting patients, ironically, was syphilis; only by the end of the 19th century had rheumatism become the most important object of cures at Aachen and Burtscheid.
Aachen was chosen as the site of several important congresses and peace treaties: the first congress of Aachen (often referred to as the Congress of Aix-la-Chapelle in English) on 2 May 1668,. leading to the First Treaty of Aachen in the same year which ended the War of Devolution.. The second congress ended with the second treaty in 1748, ending the War of the Austrian Succession.. In 1789, there was a constitutional crisis in the Aachen government,. and in 1794 Aachen lost its status as a free imperial city.
In 1629, the Aachen Jewish community was expelled from the city. In 1667, six Jews were allowed to return. Most of the Aachen Jewish community settled in Burtscheid. As recently as the late 18th century the Abbess of Burtscheid was still prevented from building a road linking her territory to the neighbouring estates of the duke of Jülich; the city of Aachen deployed its handful of soldiers to chase away road-diggers.
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Aachen
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19th century
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19th century
thumb|The modern Elisabethhalle pool
On 9 February 1801, the Peace of Lunéville removed the ownership of Aachen and the entire "left bank" of the Rhine from Germany (the Holy Roman Empire) and granted it to France. In 1815, control of the town was passed to the Kingdom of Prussia through an agreement reached by the Congress of Vienna. The third congress took place in 1818, to decide the fate of occupied Napoleonic France.
By the middle of the 19th century, industrialisation had swept away most of the city's medieval rules of production and commerce, although the remains of the city's medieval constitution were kept in place until 1801, when Aachen became the "chef-lieu du département de la Roer" in Napoleon's First French Empire. In 1815, after the Napoleonic Wars, the Kingdom of Prussia took over within the new German Confederation. The city was one of its most socially and politically backward centres until the end of the 19th century. Administered within the Rhine Province, by 1880 the population was 80,000. Starting in 1838, the railway from Cologne to Belgium passed through Aachen.. The city suffered extreme overcrowding and deplorable sanitary conditions until 1875, when the medieval fortifications were abandoned as a limit to building and new, better housing was built in the east of the city, where sanitary drainage was easiest. In December 1880, the Aachen tramway network was opened, and in 1895 it was electrified.. In the 19th century and up to the 1930s, the city was important in the production of railway locomotives and carriages, iron, pins, needles, buttons, tobacco, woollen goods, and silk goods.
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Aachen
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20th century
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20th century
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Aachen
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World War II
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World War II
thumb|upright=1.2|thumbtime=06:42|start=00:08|Films shot on 13, 14 and 15 October 1944 in Aachen by US forces
After World War I, Aachen was occupied by the Entente until 1930, along with the rest of German territory west of the Rhine. Aachen was one of the locations involved in the Rhenish Republic. On 21 October 1923, an armed mob took over the city hall. Similar actions took place in Mönchengladbach, Duisburg, and Krefeld. This republic lasted about a year..
Aachen was heavily damaged during World War II. According to Jörg Friedrich in The Fire (2008), two Allied air raids on 11 April and 24 May 1944 "radically destroyed" the city. The first killed 1,525, including 212 children, and bombed six hospitals. During the second, 442 aircraft hit two railway stations, killed 207, and left 15,000 homeless. The raids destroyed Aachen-Eilendorf and Aachen-Burtscheid..
The city and its fortified surroundings were besieged from 12 September to 21 October 1944 by the US 1st Infantry Division. with the 3rd Armored Division assisting from the south.. Around 13 October the US 2nd Armored Division, coming from the north, and got as close as Würselen,. while the 30th Infantry Division completed the encirclement of Aachen on 16 October 1944.. With reinforcements from the US 28th Infantry Division. the battle continued involving direct assaults through the heavily defended city, which forced the German garrison to surrender on 21 October 1944.
Aachen was the first German city to be captured by the Western Allies, and its residents welcomed the soldiers as liberators.. What remained of the city was destroyed—in some areas completely—during the fighting, mostly by American artillery fire and demolitions carried out by the Waffen-SS defenders. Damaged buildings included medieval churches of and the Rathaus (city hall), although Aachen Cathedral was largely unscathed. 4,000 inhabitants remained in the city; the rest had followed evacuation orders. Its first Allied-appointed mayor, Franz Oppenhoff, was assassinated by an SS commando unit.
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Aachen
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Expulsion of Aachen Jews
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Expulsion of Aachen Jews
thumb|View of the after its destruction on Kristallnacht, November 1938
On 16 May 1815, the Jewish community of the city offered an homage in its synagogue to the Prussian king, Friedrich Wilhelm III. In 1862, a large synagogue was built, later called the . By 1933, 1,345 Jews lived in the city. On Kristallnacht in 1938, the synagogue was destroyed. By the onset of World War II in 1939, many Jews had emigrated or were arrested, and only 782 remained in the city. At the end of the war in 1945, only 62 Jews lived in the city. As of 2003, 1,434 Jews were again living in Aachen.
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Aachen
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21st century
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21st century
The city of Aachen has developed into a technology hub as a by-product of hosting one of the leading universities of technology in Germany with the RWTH Aachen (Rheinisch-Westfälische Technische Hochschule), known especially for mechanical engineering, automotive and manufacturing technology as well as for its research and academic hospital Klinikum Aachen, one of the largest medical facilities in Europe.
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Aachen
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Geography
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Geography
thumb|View towards Aachen at the foothills of the High Fens, with the university hospital visible, from the Vaalserberg, the highest elevation in Aachen and of the European part of the Netherlands.
thumb|Physiogeographical location of Aachen
Aachen is located in the middle of the Meuse–Rhine Euroregion, close to the border tripoint of Germany, the Netherlands, and Belgium. The town of Vaals in the Netherlands lies nearby at about from Aachen's city centre, while the Dutch city of Heerlen and Eupen, the capital of the German-speaking Community of Belgium, are both located about from Aachen city centre. Aachen lies near the head of the open valley of the Wurm (which today flows through the city in canalised form), part of the larger basin of the Meuse, and about north of the High Fens, which form the northern edge of the Eifel uplands of the Rhenish Massif.
The maximum dimensions of the city's territory are from north to south, and from east to west. The city limits are long, of which border Belgium and the Netherlands. The highest point in Aachen, located in the far southeast of the city, lies at an elevation of above sea level. The lowest point, in the north, and on the border with the Netherlands, is at .
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Aachen
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Climate
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Climate
As the westernmost city in Germany. (and close to the Low Countries), Aachen and the surrounding area belongs to a temperate climate zone (Cfb), with humid weather, mild winters, and warm summers. Because of its location north of the Eifel and the High Fens and its subsequent prevailing westerly weather patterns, rainfall in Aachen (on average 805 mm/year) is comparatively higher than, for example, in Bonn (with 669 mm/year). Another factor in the local weather forces of Aachen is the occurrence of Foehn winds on the southerly air currents, which results from the city's geographic location on the northern edge of the Eifel.
Because the city is surrounded by hills, it suffers from inversion-related smog. Some areas of the city have become urban heat islands as a result of poor heat exchange, both because of the area's natural geography and from human activity. The city's numerous cold air corridors, which are slated to remain as free as possible from new construction, therefore play an important role in the urban climate of Aachen..
The January average is
, while the July average is . Precipitation is almost evenly spread throughout the year.
The city's oceanic climate provides comparably mild winters: While Aachen falls within the coldest extents covered by USDA plant hardiness zone 8b in the 1991–2020 period, having an average yearly minimum of -9.22 °C (15.4 °F), the Canadian city of Regina, Saskatchewan which is located at a similar latitude but at the heart of the North American landmass, far away from the sea's moderating effects, is classified as being in zone 3a.
In the 1991–2020 period, the last freeze (at 2 m above ground) of spring occurred on April 28th and the first fall freeze on October 13th, on average.
The Aachen weather station has recorded the following extreme values:
Highest Temperature on 25 July 2019.
Warmest Minimum on 29 July 1947.
Coldest Maximum on 22 January 1940.
Lowest Temperature on 11 January 1945.
Highest Daily Precipitation on 14 July 2021.
Wettest Month in July 2021.
Wettest Year in 1966.
Driest Year in 1959.
Earliest Snowfall: 4 November 1941.
Latest Snowfall: 30 April 1938.
Longest annual sunshine: 2,128.4 hours in 2003.
Shortest annual sunshine: 1,277.4 hours in 1981.
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Aachen
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Geology
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Geology
thumb|Layered sandstone and claystone formation from the Devonian period below St. Adalbert Church in Aachen
The geology of Aachen is very structurally heterogeneous. The oldest occurring rocks in the area surrounding the city originate from the Devonian period and include carboniferous sandstone, greywacke, claystone and limestone. These formations are part of the Rhenish Massif, north of the High Fens. In the Pennsylvanian subperiod of the Carboniferous geological period, these rock layers were narrowed and folded as a result of the Variscan orogeny. After this event, and over the course of the following 200 million years, this area has been continuously flattened.
During the Cretaceous period, the ocean penetrated the continent from the direction of the North Sea up to the mountainous area near Aachen, bringing with it clay, sand, and chalk deposits. While the clay (which was the basis for a major pottery industry in nearby Raeren) is mostly found in the lower areas of Aachen, the hills of the Aachen Forest and the Lousberg were formed from upper Cretaceous sand and chalk deposits. More recent sedimentation is mainly located in the north and east of Aachen and was formed through tertiary and quaternary river and wind activities.
Along the major thrust fault of the Variscan orogeny, there are over 30 thermal springs in Aachen and Burtscheid. Additionally, the subsurface of Aachen is traversed by numerous active faults that belong to the Rurgraben fault system, which has been responsible for numerous earthquakes in the past, including the 1756 Düren earthquake. and the 1992 Roermond earthquake,. which was the strongest earthquake ever recorded in the Netherlands.
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Aachen
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Demographics
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Demographics
+ Largest groups of foreign residents Nationality Population (30.06.2024) 6,745 4,365 3,998 3,751 3,662 2,369 1,786 1,836 1,745 1,542 1,495
Aachen had 245,885 inhabitants as of 31 December 2015, of whom 118,272 were female, and 127,613 were male.
At the end of 2009, the foreign-born residents of Aachen made up 13.6 percent of the total population.. A significant portion of foreign residents are students at the RWTH Aachen University.
Year Population 1994 246,570. 2007 247,740 2011 238,665 2014 243,336 2015 245,885
thumb|120px|Age distribution of Aachen's population next to Germany's (2014)
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Aachen
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Dialect
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Dialect
Aachen is at the western end of the Benrath line that divides High German to the south from the rest of the West Germanic speech area to the north. Aachen's local dialect is called Öcher Platt and belongs to Ripuarian.
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Aachen
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Boroughs
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Boroughs
The city is divided into seven administrative districts, or boroughs, each with its own district council, district leader, and district authority. The councils are elected locally by those who live within the district, and these districts are further subdivided into smaller sections for statistical purposes, with each sub-district named by a two-digit number.
The districts of Aachen, including their constituent statistical districts, are:
Aachen-Mitte: 10 Markt, 13 Theater, 14 Lindenplatz, 15 St. Jakob, 16 Westpark, 17 Hanbruch, 18 Hörn, 21 Ponttor, 22 Hansemannplatz, 23 Soers, 24 Jülicher Straße, 25 Kalkofen, 31 Kaiserplatz, 32 Adalbertsteinweg, 33 Panneschopp, 34 Rothe Erde, 35 Trierer Straße, 36 Frankenberg, 37 Forst, 41 Beverau, 42 Burtscheid Kurgarten, 43 Burtscheid Abbey, 46 Burtscheid Steinebrück, 47 Marschiertor, 48 Hangeweiher
Brand: 51 Brand
Eilendorf: 52 Eilendorf
Haaren: 53 Haaren (including Verlautenheide)
Kornelimünster/Walheim: 61 Kornelimünster, 62 Oberforstbach, 63 Walheim
Laurensberg: 64 Vaalserquartier, 65 Laurensberg
Richterich: 88 Richterich
Regardless of official statistical designations, there are 50 neighbourhoods and communities within Aachen, here arranged by district:
thumb|Aachen districts and quarters
Aachen-Mitte: Beverau, Bildchen, Burtscheid, Forst, Frankenberg, Grüne Eiche, Hörn, Lintert, Pontviertel, Preuswald, Ronheide, Rosviertel, Rothe Erde, Stadtmitte, Steinebrück, West
Brand: Brand, Eich, Freund, Hitfeld, Niederforstbach
Eilendorf: Eilendorf, Nirm
Haaren: Haaren, Hüls, Verlautenheide
Kornelimünster/Walheim: Friesenrath, Hahn, Kitzenhaus, Kornelimünster, Krauthausen, Lichtenbusch, Nütheim, Oberforstbach, Sief, Schleckheim, Schmithof, Walheim
Laurensberg: Gut Kullen, Kronenberg, Laurensberg, Lemiers, Melaten, Orsbach, Seffent, Soers, Steppenberg, Vaalserquartier, Vetschau
Richterich: Horbach, Huf, Richterich
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Aachen
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Neighbouring communities
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Neighbouring communities
The following cities and communities border Aachen, clockwise from the northwest:
Herzogenrath, Würselen, Eschweiler, Stolberg and Roetgen (which are all in the district of Aachen); Raeren, Kelmis and Plombières (Liège Province in Belgium) as well as Vaals, Gulpen-Wittem, Simpelveld, Heerlen and Kerkrade (all in Limburg Province in the Netherlands).
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Aachen
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Politics
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Politics
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Aachen
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Mayor
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Mayor
The current mayor of Aachen is Sibylle Keupen, an independent endorsed by Alliance 90/The Greens, since 2020. The most recent mayoral election was held on 13 September 2020, with a runoff held on 27 September, and the results were as follows:
! rowspan=2 colspan=2| Candidate
! rowspan=2| Party
! colspan=2| First round
! colspan=2| Second round
|-
! Votes
! %
! Votes
! %
|-
| bgcolor=|
| align=left| Sibylle Keupen
| align=left| Independent (Green)
| 39,662
| 38.9
| 53,685
| 67.4
|-
| bgcolor=|
| align=left| Harald Baal
| align=left| Christian Democratic Union
| 25,253
| 24.8
| 26,003
| 32.6
|-
| bgcolor=|
| align=left| Mathias Dopatka
| align=left| Social Democratic Party
| 23,031
| 22.6
|-
| bgcolor=|
| align=left| Markus Mohr
| align=left| Alternative for Germany
| 3,387
| 3.3
|-
| bgcolor=|
| align=left| Wilhelm Helg
| align=left| Free Democratic Party
| 3,122
| 3.1
|-
| bgcolor=|
| align=left| Leo Deumens
| align=left| The Left
| 2,397
| 2.4
|-
| bgcolor=|
| align=left| Hubert vom Venn
| align=left| Die PARTEI
| 2,112
| 2.1
|-
| bgcolor=|
| align=left| Jörg Polzin
| align=left| Independent
| 938
| 0.9
|-
|
| align=left| Ralf Haupts
| align=left| Independent Voters' Association Aachen
| 932
| 0.9
|-
| bgcolor=|
| align=left| Matthias Achilles
| align=left| Pirate Party Germany
| 848
| 0.8
|-
| bgcolor=|
| align=left| Adonis Böving
| align=left| Independent
| 317
| 0.3
|-
! colspan=3| Valid votes
! 101,999
! 99.2
! 79,688
! 99.3
|-
! colspan=3| Invalid votes
! 819
! 0.8
! 532
! 0.7
|-
! colspan=3| Total
! 102,818
! 100.0
! 80,220
! 100.0
|-
! colspan=3| Electorate/voter turnout
! 192,502
! 53.4
! 192,435
! 41.7
|-
| colspan=7| Source: State Returning Officer
|}
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Aachen
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City council
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City council
thumb|upright 1.2|Results of the 2020 city council election
The Aachen city council governs the city alongside the mayor. The most recent city council election was held on 13 September 2020, and the results were as follows:
! colspan=2| Party
! Votes
! %
! +/-
! Seats
! +/-
|-
| bgcolor=|
| align=left| Alliance 90/The Greens (Grüne)
| 34,712
| 34.1
| 17.5
| 20
| 7
|-
| bgcolor=|
| align=left| Christian Democratic Union (CDU)
| 25,268
| 24.8
| 11.5
| 14
| 14
|-
| bgcolor=|
| align=left| Social Democratic Party (SPD)
| 18,676
| 18.3
| 7.7
| 11
| 9
|-
| bgcolor=|
| align=left| Free Democratic Party (FDP)
| 5,042
| 4.9
| 0.5
| 3
| ±0
|-
| bgcolor=|
| align=left| The Left (Die Linke)
| 4,694
| 4.6
| 1.5
| 3
| 2
|-
| bgcolor=|
| align=left| Alternative for Germany (AfD)
| 3,816
| 3.7
| 1.2
| 2
| ±0
|-
| bgcolor=|
| align=left| Volt Germany (Volt)
| 3,784
| 3.7
| New
| 2
| New
|-
| bgcolor=|
| align=left| Die PARTEI (PARTEI)
| 2,295
| 2.3
| 1.8
| 1
| 1
|-
|
| align=left| Independent Voters' Association Aachen (UWG)
| 1,632
| 1.6
| 0.2
| 1
| ±0
|-
| bgcolor=|
| align=left| Pirate Party Germany (Piraten)
| 1,226
| 1.2
| 2.2
| 1
| 2
|-
| colspan=7 bgcolor=lightgrey|
|-
| bgcolor=|
| align=left| Ecological Democratic Party (ÖDP)
| 673
| 0.7
| New
| 0
| New
|-
|
| align=left| Voter Group
| 45
| 0.0
| New
| 0
| New
|-
! colspan=2| Valid votes
! 101,863
! 99.1
!
!
!
|-
! colspan=2| Invalid votes
! 918
! 0.9
!
!
!
|-
! colspan=2| Total
! 102,781
! 100.0
!
! 58
! 18
|-
! colspan=2| Electorate/voter turnout
! 192,502
! 53.4
! 0.7
!
!
|-
| colspan=7| Source: State Returning Officer
|}
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Aachen
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Main sights
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Main sights
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Aachen
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Cathedral
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Cathedral
thumb|upright=1.2|Aachen Cathedral
Aachen Cathedral was erected on the orders of Charlemagne. Construction began c. AD 796, and it was, on completion c. 798,. the largest cathedral north of the Alps. It was modelled after the Basilica of San Vitale, in Ravenna, Italy, and was built by Odo of Metz. Charlemagne also desired for the chapel to compete with the Lateran Palace, both in quality and authority. It was originally built in the Carolingian style, including marble covered walls, and mosaic inlay on the dome.. On his death, Charlemagne's remains were interred in the cathedral and can be seen there to this day. The cathedral was extended several times in later ages, turning it into a curious and unique mixture of building styles. The throne and gallery portion date from the Ottonian, with portions of the original opus sectile floor still visible. The 13th century saw gables being added to the roof, and after the fire of 1656, the dome was rebuilt. Finally, a choir was added around the start of the 15th century.
After Frederick Barbarossa canonised Charlemagne in 1165 the chapel became a destination for pilgrims. For 600 years, from 936 to 1531, Aachen Cathedral was the church of coronation for 30 German kings and 12 queens. The church built by Charlemagne is still the main attraction of the city.. In addition to holding the remains of its founder, it became the burial place of his successor Otto III. In the upper chamber of the gallery, Charlemagne's marble throne is housed.. Aachen Cathedral has been designated as a UNESCO World Heritage Site.
Most of the marble and columns used in the construction of the cathedral were brought from Rome and Ravenna, including the sarcophagus in which Charlemagne was eventually laid to rest.. A bronze bear from Gaul was placed inside, along with an equestrian statue from Ravenna, believed to be Theodric, in contrast to a wolf and a statue of Marcus Aurelius in the Capitoline. Bronze pieces such as the doors and railings, some of which have survived to present day, were cast in a local foundry. Finally, there is uncertainty surrounding the bronze pine cone in the chapel, and where it was created. Wherever it was made, it was also a parallel to a piece in Rome, this in Old St. Peter's Basilica.
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Aachen
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Cathedral Treasury
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Cathedral Treasury
thumb|upright|Cross of Lothair, Aachen Cathedral Treasury
Aachen Cathedral Treasury has housed, throughout its history, a collection of liturgical objects. The origin of this church treasure is in dispute as some say Charlemagne himself endowed his chapel with the original collection, while the rest were collected over time. Others say all of the objects were collected over time, from such places as Jerusalem and Constantinople. The location of this treasury has moved over time and was unknown until the 15th century when it was located in the Matthiaskapelle (St. Matthew's Chapel) until 1873, when it was moved to the Karlskapelle (Charles' Chapel). From there it was moved to the Hungarian Chapel in 1881 and in 1931 to its present location next to the Allerseelenkapelle (Poor Souls' Chapel). Only six of the original Carolingian objects have remained, and of those only three are left in Aachen: the Aachen Gospels, a diptych of Christ, and an early Byzantine silk. The Coronation Gospels and a reliquary burse of St. Stephen were moved to Vienna in 1798 and the Talisman of Charlemagne was given as a gift in 1804 to Josephine Bonaparte and subsequently to Rheims Cathedral. 210 documented pieces have been added to the treasury since its inception, typically to receive in return legitimisation of linkage to the heritage of Charlemagne. The Lothar Cross, the Gospels of Otto III and multiple additional Byzantine silks were donated by Otto III. Part of the Pala d'Oro and a covering for the Aachen Gospels were made of gold donated by Henry II. Frederick Barbarossa donated the candelabrum that adorns the dome and also once "crowned" the Shrine of Charlemagne, which was placed underneath in 1215. Charles IV donated a pair of reliquaries. Louis XI gave, in 1475, the crown of Margaret of York, and, in 1481, another arm reliquary of Charlemagne. Maximilian I and Charles V both gave numerous works of art by Hans von Reutlingen. Continuing the tradition, objects continued to be donated until the present, each indicative of the period of its gifting, with the last documented gift being a chalice from 1960 made by Ewald Mataré.
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Aachen
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Rathaus
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Rathaus
thumb|Aachen Rathaus seen from the south
The Aachen Rathaus, (English: Aachen City Hall or Aachen Town Hall) dated from 1330, lies between two central squares, the Markt (marketplace) and the Katschhof (between city hall and cathedral). The coronation hall is on the first floor of the building. Inside one can find five frescoes by the Aachen artist Alfred Rethel which show legendary scenes from the life of Charlemagne, as well as Charlemagne's signature. Also, precious replicas of the Imperial Regalia are kept here.
Since 2009, the city hall has been a station on the Route Charlemagne, a tour programme by which historical sights of Aachen are presented to visitors. At the city hall, a museum exhibition explains the history and art of the building and gives a sense of the historical coronation banquets that took place there. A portrait of Napoleon from 1807 by Louis-André-Gabriel Bouchet and one of his wife Joséphine from 1805 by Robert Lefèvre are viewable as part of the tour.
As before, the city hall is the seat of the mayor of Aachen and of the city council, and annually the Charlemagne Prize is awarded there.
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Aachen
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Other sights
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Other sights
The Grashaus, a late medieval house at the Fischmarkt, is one of the oldest non-religious buildings in central Aachen. It hosted the city archive, and before that, the Grashaus was the city hall until the present building took over this function.
The Elisenbrunnen is one of the most famous sights of Aachen. It is a neo-classical hall covering one of the city's famous fountains. It is just a minute away from the cathedral. Just a few steps in a south-easterly direction lies the 19th-century theatre.
Also of note are two remaining city gates, the Ponttor (Pont gate), northwest of the cathedral, and the Marschiertor (marching gate), close to the central railway station. There are also a few parts of both medieval city walls left, most of them integrated into more recent buildings, but some others still visible. There are even five towers left, some of which are used for housing.
St. Michael's Church, Aachen was built as a church of the Aachen Jesuit Collegium in 1628. It is attributed to the Rhine mannerism, and a sample of a local Renaissance architecture. The rich façade remained unfinished until 1891, when the architect Peter Friedrich Peters added to it. The church is a Greek Orthodox church today, but the building is used also for concerts because of its good acoustics.
The synagogue in Aachen, which was destroyed on the Night of Broken Glass (Kristallnacht), 9 November 1938, was reinaugurated on 18 May 1995... One of the contributors to the reconstructions of the synagogue was Jürgen Linden, the Lord Mayor of Aachen from 1989 to 2009.
There are numerous other notable churches and monasteries, a few remarkable 17th- and 18th-century buildings in the particular Baroque style typical of the region, a synagogue, a collection of statues and monuments, park areas, cemeteries, among others. Among the museums in the town are the Suermondt-Ludwig Museum, which has a fine sculpture collection and the Aachen Museum of the International Press, which is dedicated to newspapers from the 16th century to the present.. The area's industrial history is reflected in dozens of 19th- and early 20th-century manufacturing sites in the city.
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Aachen
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Economy
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Economy
thumb|Ford Research Center, Aachen
Aachen is the administrative centre for the coal-mining industries in neighbouring places to the northeast.
Products manufactured in Aachen include electrical goods, fine woolen textiles, foodstuffs (chocolate and candy), glass, machinery, rubber products, furniture, metal products. Also in and around Aachen chemicals, plastics, cosmetics, and needles and pins are produced.. Though once a major player in Aachen's economy, today glassware and textile production make up only 10% of total manufacturing jobs in the city. There have been a number of spin-offs from the university's IT technology department.
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Aachen
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Electric vehicle manufacturing
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Electric vehicle manufacturing
thumb|StreetScooter Work as DHL delivery van (2016)
In June 2010, Achim Kampker, together with Günther Schuh, founded a small company to develop electric powered light utility vehicles; in August 2014, it was renamed StreetScooter GmbH. This started as a privately organised research initiative at the RWTH Aachen University, before becoming the independent company in Aachen. Kampker was also the founder and chairman of the European Network for Affordable and Sustainable Electromobility. In May 2014, the company announced that the city of Aachen, the city council Aachen and the savings bank Aachen had ordered electric vehicles from the company. In late 2014, approximately 70 employees were manufacturing 200 vehicles annually in the premises of the Waggonfabrik Talbot, the former Talbot/Bombardier plant in Aachen.
In December 2014 DHL Group purchased the StreetScooter company from Günther, operating it as a wholly owned subsidiary.Deutsche Post DHL übernimmt StreetScooter GmbH 9.
In 2015, Günther founded a new electric vehicle company, e.GO Mobile, which started producing the e.GO Life electric passenger car and other vehicles in April 2019.
By April 2016, StreetScooter announced that it would produce 2000 of its electric vans, branded the Work, in Aachen by the end of the year, and would be scaling up to manufacture approximately 10,000 Works annually, starting in 2017, also in Aachen. At the time, this target would make it the largest electric light utility vehicle manufacturer in Europe, surpassing Renault's smaller Kangoo Z.E.
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Aachen
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Culture
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Culture
thumb|Aachen is also famous for its carnival (Karneval, Fasching), in which families dress in colourful costumes.
In 1372, Aachen became the first coin-minting city in the world to regularly place an Anno Domini date on a general circulation coin, a groschen.
The Scotch Club in Aachen was the first discothèque in Germany, opened from 19 October 1959 until 1992. Klaus Quirini as DJ Heinrich was the first DJ ever.
The thriving Aachen black metal scene is among the most notable in Germany, with such bands as Nagelfar, The Ruins of Beverast, Graupel and Verdunkeln.
The local speciality of Aachen is an originally hard type of sweet bread, baked in large flat loaves, called Aachener Printen. Unlike Lebkuchen, a German form of gingerbread sweetened with honey, Printen use a syrup made from sugar. Today, a soft version is sold under the same name which follows an entirely different recipe.
Asteroid 274835 Aachen, discovered by amateur astronomer Erwin Schwab in 2009, was named after the city. The official was published by the Minor Planet Center on 8 November 2019 ().
Kammerchor Carmina Mundi, a professional chamber choir
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Aachen
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Education
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Education
thumb|left|The main building of RWTH Aachen University
thumb|right|Typical Aachen street with early 20th-century Gründerzeit houses
thumb|Another example of Aachen early 20th-century Gründerzeit houses
RWTH Aachen University, established as Polytechnicum in 1870, is one of Germany's Universities of Excellence with strong emphasis on technological research, especially for electrical and mechanical engineering, computer sciences, physics, and chemistry. The university clinic attached to the RWTH, the Klinikum Aachen, is the biggest single-building hospital in Europe.. Over time, a host of software and computer industries have developed around the university. It also maintains a botanical garden (the Botanischer Garten Aachen).
FH Aachen, Aachen University of Applied Sciences (AcUAS) was founded in 1971. The AcUAS offers a classic engineering education in professions such as mechatronics, construction engineering, mechanical engineering or electrical engineering. German and international students are educated in more than 20 international or foreign-oriented programmes and can acquire German as well as international degrees (Bachelor/Master) or Doppelabschlüsse (double degrees). Foreign students account for more than 21% of the student body.
The Katholische Hochschule Nordrhein-Westfalen – Abteilung Aachen (Catholic University of Applied Sciences Northrhine-Westphalia – Aachen department). offers its some 750 students a variety of degree programmes: social work, childhood education, nursing, and co-operative management. It also has the only programme of study in Germany especially designed for mothers..
The (Cologne University of Music) is one of the world's foremost performing arts schools and one of the largest music institutions for higher education in Europe. with one of its three campuses in Aachen.. The Aachen campus substantially contributes to the Opera/Musical Theatre master's programme by collaborating with the Theater Aachen and the recently established musical theatre chair through the Rheinische Opernakademie.
The German army's Technical School (Ausbildungszentrum Technik Landsysteme) is in Aachen..
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Aachen
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Sports
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Sports
thumb|left|New Tivoli, home ground of Alemannia Aachen
The annual CHIO (short for the French term Concours Hippique International Officiel) is the biggest equestrian meeting of the world and among horsemen is considered to be as prestigious for equitation as the tournament of Wimbledon for tennis. Aachen hosted the 2006 FEI World Equestrian Games.
The local football team Alemannia Aachen had a short run in Germany's first division, after its promotion in 2006. However, the team could not sustain its status and is now back in the third division. The stadium "Tivoli", opened in 1928, served as the venue for the team's home games and was well known for its incomparable atmosphere throughout the whole of the second division.. Before the old stadium's demolition in 2011, it was used by amateurs, whilst the Bundesliga Club held its games in the new stadium "Neuer Tivoli" – meaning New Tivoli—a couple of metres down the road. The building work for the stadium which has a capacity of 32,960, began in May 2008 and was completed by the beginning of 2009.
The Ladies in Black women's volleyball team (part of the "PTSV Aachen" sports club since 2013) has played in the first German volleyball league (DVL) since 2008.
In June 2022, the local basketball club BG Aachen e.V. was promoted to the 1st regional league.
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Aachen
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Transport
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Transport
thumb|Aachen Central Station
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Aachen
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Rail
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Rail
Aachen's railway station, the Hauptbahnhof (Central Station), was constructed in 1841 for the Cologne–Aachen railway line. In 1905, it was moved closer to the city centre. It serves main lines to Cologne, Mönchengladbach and Liège as well as branch lines to Heerlen, Alsdorf, Stolberg and Eschweiler. ICE high speed trains from Brussels via Cologne to Frankfurt am Main and Eurostar trains from Paris to Cologne also stop at Aachen Central Station. Four RE lines and two RB lines connect Aachen with the Ruhrgebiet, Mönchengladbach, Spa (Belgium), Düsseldorf and the Siegerland. The Euregiobahn, a regional railway system, reaches several minor cities in the Aachen region.
There are four smaller stations in Aachen: Aachen West, Aachen Schanz, Aachen-Rothe Erde and Eilendorf. Slower trains stop at these. Aachen West has gained in importance with the expansion of RWTH Aachen University.
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Aachen
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Intercity bus stations
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Intercity bus stations
There are two stations for intercity bus services in Aachen: Aachen West station, in the north-west of the city, and Aachen Wilmersdorfer Straße, in the north-east.
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Aachen
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Public transport
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Public transport
thumb|right|Bi-articulated bus of the city's transit authority ASEAG, at the university hospital bus stop
The first horse tram line in Aachen opened in December 1880. After electrification in 1895, it attained a maximum length of in 1915, thus becoming the fourth-longest tram network in Germany. Many tram lines extended to the surrounding towns of Herzogenrath, Stolberg, Alsdorf as well as the Belgian and Dutch communes of Vaals, Kelmis (then Altenberg) and Eupen. The Aachen tram system was linked with the Belgian national interurban tram system. Like many tram systems in Western Europe, the Aachen tram suffered from poorly-maintained infrastructure and was so deemed unnecessary and disrupting for car drivers by local politics. On 28 September 1974, the last line 15 (Vaals–Brand) operated for one last day and was then replaced by buses. A proposal to reinstate a tram/light rail system under the name Campusbahn was dropped after a referendum.
Today, the ASEAG (Aachener Straßenbahn und Energieversorgungs-AG, literally "Aachen tram and power supply company") operates a bus network with 68 bus routes. Because of the location at the border, many bus routes extend to Belgium and the Netherlands. Lines 14 to Eupen, Belgium and 44 to Heerlen, Netherlands are jointly operated with Transport en Commun and Veolia Transport Nederland, respectively. ASEAG is one of the main participants in the Aachener Verkehrsverbund (AVV), a tariff association in the region. Along with ASEAG, city bus routes of Aachen are served by private contractors such as Sadar, Taeter, Schlömer, or DB Regio Bus. Line 350, which runs from Maastricht, also enters Aachen.
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Aachen
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Roads
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Roads
Aachen is connected to the Autobahn A4 (west-east), A44 (north-south) and A544 (a smaller motorway from the A4 to the Europaplatz near the city centre). There are plans to eliminate traffic jams at the Aachen road interchange.
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Aachen
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Airport
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Airport
Maastricht Aachen Airport is the main airport of Aachen and Maastricht. It is located around northwest of Aachen. There is a shuttle-service between Aachen and the airport.
Recreational aviation is served by the (formerly military) Aachen Merzbrück Airfield.
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Aachen
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Charlemagne Prize
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Charlemagne Prize
thumb|right|upright=0.8|Chancellor of Germany Angela Merkel, wearing the Charlemagne Prize awarded to her in 2008
Since 1950, a committee of Aachen citizens annually awards the Charlemagne Prize () to personalities of outstanding service to the unification of Europe. It is traditionally awarded on Ascension Day at the City Hall. In 2016, the Charlemagne Award was awarded to Pope Francis.
The International Charlemagne Prize of Aachen was awarded in the year 2000 to US president Bill Clinton, for his special personal contribution to co-operation with the states of Europe, for the preservation of peace, freedom, democracy and human rights in Europe, and for his support of the enlargement of the European Union. In 2004, Pope John Paul II's efforts to unite Europe were honoured with an "Extraordinary Charlemagne Medal", which was awarded for the only time ever.
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Aachen
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Literature
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Literature
Aix is the destination in Robert Browning's poem "How They Brought the Good News from Ghent to Aix", which was published in Dramatic Romances and Lyrics, 1845.James F. Loucks, and Andrew M. Satuffer, eds. Robert Browning's Poetry: Authoritative Texts. Criticism. Norton, 2nd ed. 1979. The poem is a first-person narrative told, in breathless galloping meter, by one of three riders; an urgent midnight errand to deliver "the news which alone could save Aix from her fate".
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Aachen
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Notable people
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Notable people
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Aachen
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Twin towns – sister cities
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Twin towns – sister cities
Aachen is twinned with:
Montebourg, France (1960)
Reims, France (1967)
Halifax, England (1979)
Toledo, Spain (1985)
Ningbo, China (1986)
Naumburg, Germany (1988)
Arlington County, United States (1993)
Sarıyer, Istanbul, Turkey (2013)
Cape Town, South Africa (2017)
Chernihiv, Ukraine (2023)
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Aachen
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Former twin towns
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Former twin towns
Kostroma, Russia (2005, suspended since March 2022)
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Aachen
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See also
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See also
Aachen (district)
Aachen Prison
Aachen tram
Aachener
Aachener Chronik
Aachener Bachverein
List of mayors of Aachen
Council of Aachen
Treaty of Aix-la-Chapelle (disambiguation)
Maastricht Aachen Airport
Computer museum Aachen
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Aachen
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Notes
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Notes
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Aachen
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References
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References
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Aachen
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Sources
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Sources
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Aachen
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Further reading
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Further reading
Rice, Eric, Music and Ritual at Charlemagne's Marienkirche in Aachen. Kassel: Merseburger, 2009.
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Aachen
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External links
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External links
Category:Aachen (district)
Category:Belgium–Germany border crossings
Category:Catholic pilgrimage sites
Category:Cities in North Rhine-Westphalia
Category:1st century
Category:Free imperial cities
Category:Jewish German history
Category:Matter of France
Category:Populated places established in the 1st century
Category:Rhineland
Category:Roman towns and cities in Germany
Category:765
Category:Spa towns in Germany
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Aachen
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Table of Content
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Short description, Etymology, History, Early history, Middle Ages, Manuscript production, 16th–18th centuries, 19th century, 20th century, World War II, Expulsion of Aachen Jews, 21st century, Geography, Climate, Geology, Demographics, Dialect, Boroughs, Neighbouring communities, Politics, Mayor, City council, Main sights, Cathedral, Cathedral Treasury, Rathaus, Other sights, Economy, Electric vehicle manufacturing, Culture, Education, Sports, Transport, Rail, Intercity bus stations, Public transport, Roads, Airport, Charlemagne Prize, Literature, Notable people, Twin towns – sister cities, Former twin towns, See also, Notes, References, Sources, Further reading, External links
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Agate
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short description
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Agate ( ) is a banded variety of chalcedony. Agate stones are characterized by alternating bands of different colored chalcedony and sometimes include macroscopic quartz. They are common in nature and can be found globally in a large number of different varieties. There are some varieties of chalcedony without bands that are commonly called agate (moss agate, fire agate, etc.); however, these are more properly classified solely as varieties of chalcedony. Agates are primarily formed as nodules within volcanic rock, but they can also form in veins or in sedimentary rock. Agate has been popular as a gemstone in jewelry for thousands of years, and today it is also popular as a collector's stone. Some duller agates sold commercially are artificially dyed to enhance their color.
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Agate
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Etymology
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Etymology
Agate was given its name by Theophrastus, a Greek philosopher and naturalist. He discovered the stone c. 350 BCE along the shoreline of the River Achates (), now the Dirillo River, on the Italian island of Sicily, which at the time was a Greek territory.
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Agate
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Formation and properties
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Formation and properties
thumb|Geode agate
Agates are most commonly found as nodules within the cavities of volcanic rocks such as basalt, andesite, and rhyolite. These cavities, called vesicles (amygdaloids when filled), are gas bubbles that were trapped inside the lava when it cooled. The vesicles are later filled with hot, silica-rich water from the surrounding environment, forming a silica gel. This gel crystallizes through a complex process to form agates. Since agates usually form in lavas poor in free silica, there are multiple theories of where the silica originates from, including micro-shards of silica glass from volcanic ash or tuff deposits and decomposing plant or animal matter. Agates are much harder than the rocks they form in, so they are frequently found detached from their host rock.
Geologists generally understand the early stages of agate formation, but the specific processes that result in band development are still widely debated. Since they form in cavities within host rock, agate formation cannot be directly observed, and unlike most other crystals, agates have never been successfully lab-grown.
Agate is composed of multiple bands, or layers, of chalcedony fibers, specifically length-fast chalcedony fibers and sometimes quartzine (length-slow chalcedony fibers). Agate can also contain opal, an amorphous, hydrated form of silica. In wall-banded agates, the fibers grow radially from the vesicle walls inward, perpendicular to the direction of the bands. The vesicle walls are often coated with thin layers of celadonite or chlorite, soft, green phyllosilicate minerals that form from the reaction of hot, silica-rich water with the rock. This coating provides a rough surface for the chalcedony fibers to form on, initially as radial spherulites. The rough surface also causes agate husks to have a pitted appearance once the coating has been weathered away or removed. Sometimes, the spherulites grow around mineral inclusions, resulting in eyes, tubes, and sagenitic agates. The first layer of spherulitic chalcedony is typically clear, followed by successive growth bands of chalcedony alternated with chemically precipitated color bands, primarily iron oxides. The center is often macrocrystalline quartz (quartz with visible crystals), which can also occur in bands and forms when there is not enough water in the silica gel to promote chalcedony polymerization. When the silica concentration of the gel is too low, a hollow center forms, called an agate geode.
Quartz forms crystals around the cavity, with the apex of each crystal pointing towards the center. Occasionally, the quartz may be colored, such as amethyst or smoky quartz. Level-banded agates form when chalcedony precipitates out of solution in the direction of gravity, resulting in horizontal layers of microscopic chalcedony spherulites. Enhydro agates, or enhydros, form when water becomes trapped within an agate (or chalcedony) nodule or geode, often long after its formation.
Agates can also form within rock fissures, called veins. Vein agates form in a manner similar to nodular agates, and they include most lace agates, such as blue lace agate and crazy lace agate.
Less commonly, agates can form as nodules within sedimentary rock, such as limestone, dolomite or tuff. These agates form when silica replaces another mineral, or silica-rich water fills cavities left by decomposed plant or animal matter. Sedimentary agates also include fossil agates, which form when silica replaces the original composition of an organic material. This process is called silicification, a form of petrification. Examples include petrified wood, agatized coral, and Turritella agate (Elimia tenera). Although these fossils are often referred to as being "agatized", they are only true agates when they are banded.
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Agate
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Varieties (by structure)
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Varieties (by structure)
Agates are broadly separated into two categories based the type of banding they exhibit. Wall banding, also called concentric banding or adhesional banding, occurs when agate bands follow the shape of the cavity they formed in. Level banding, also called water-level banding, gravitational banding, horizontal banding, parallel banding, or Uruguay-type banding, occurs when agate bands form in straight, parallel lines. Level banding is less common and usually occurs together with wall banding.
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Agate
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Wall-banded agates
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Wall-banded agates
Fortification agates have very tight, well-defined bands. They get their name from their appearance resembling the walls of a fort. Fortification agates are one the most common varieties, and they are what most people think of when they hear the word "agate".
Lace agates exhibit a lace-like pattern of bands with many swirls, eyes, bends, and zigzags. Unlike most agates, they usually form in veins instead of nodules.
Faulted agates occur when agate bands are broken and slightly shifted by rock movement and then re-cemented together by chalcedony. They have the appearance of rock layers with fault lines running through them. Brecciated agates have also had their bands broken apart and re-cemented with chalcedony, but they consist of disjointed band fragments at random angles. They are a form of breccia, which is a textural term for any rock composed of angular fragments.
Eye agates have one or more circular, concentric rings on their surface. These "eyes" are actually hemispheres that form on the husk of the agate and extend inward like a bowl. Tube agates contain tunnel-like structures that extend all the way through the agate. These "tubes" may sometimes be banded or hollow, or both. Both tube and eye agates form when chalcedony grows around a needle-shaped crystal of another mineral embedded within the agate, forming stalactitic structures. Visible "eyes" can also appear on the surface of tube agates if a cut is made (or the agate is weathered) perpendicular to the stalactitic structure.
Dendritic agates have dark-colored, fern-like patterns (dendrites) on the surface or the spaces between bands. They are composed of manganese or iron oxides. Moss agates exhibit a moss-like pattern and are usually green or brown in color. They form when dendritic structures on the surface of an agate are pushed inward with the silica gel during their formation. Moss agate was once believed to be petrified moss, until it was discovered the moss-like formations are actually composed of celadonite, hornblende, or a chlorite mineral. Plume agates are a type of moss agate, but the dendritic "plumes" form tree-like structures within the agate. They are often bright red (from inclusions of hematite) or bright yellow (from inclusions of goethite). While dendrites frequently occur in banded agates, moss and plume agates usually lack bands altogether. Therefore, they are not true agates according to the mineralogical definition.
Iris agates have bands that are so microscopically fine that when thinly sliced, they cause white light to be diffracted into its spectral colors. This "iris effect" usually occurs in colorless agates, but it can also occur in brightly colored ones.
Sagenitic agates, or sagenites, have acicular (needle-shaped) inclusions of another mineral, usually anhydrite, aragonite, goethite, rutile, or a zeolite. Chalcedony often forms tubes around these crystals and may eventually replace the original mineral, resulting in a pseudomorph. The term "sagenite" was originally a name for a type of rutile, and later rutilated quartz. It has since been used to describe any quartz variety with acicular inclusions of any mineral.
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Agate
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Level-banded agates
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Level-banded agates
Agates with level banding are traditionally called onyx, although the formal definition of the term onyx refers to color pattern, not the shape of the bands. Accordingly, the name "onyx" is also used for wall-banded agates. Onyx is also frequently misused as a name for banded calcite. The name originates from the Greek word for the human nail, which has parallel ridges. Typically, onyx bands alternate between black and white or other light and dark colors. Sardonyx is a variety with red-to-brown bands alternated with either white or black bands.
Thunder eggs are frequently level-banded, however they may also have wall banding. Level banding is also common in Lake Superior agates.
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Agate
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Varieties (by locality)
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Varieties (by locality)
Agates are very common, and they have been found on every continent, including Antarctica. In addition to names used to describe their structure, numerous geological, local, and trade names are applied to agates from different localities. Below is a list of known agate localities and the names of the agates that are found there. This list is not exhaustive.
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Agate
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Africa
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Africa
Blue lace agate is a pale blue and white lace agate found primarily in Namibia. These agates formed in dolomite associated with igneous rock.
Botswana agates are found in basaltic rocks of the Permian age in Botswana. They feature contrasting bands of purple, pink, black, grey, and white. Like Lake Superior agates, they are typically small, averaging in diameter.
Malawi agates are typically bright red or orange with contrasting white bands, but some are pink and blue. They can be found in Malawi, and they likely formed in volcanic rock of Permian age.
Agates have also been found in Egypt, Madagascar, South Africa, and Zimbabwe.
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Agate
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Antarctica
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Antarctica
White and clear banded agates have been found by scientists at Bellingshausen Station, a Russian outpost on King George Island.
thumb|center|215px|Agate from King George Island, Antarctica
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Agate
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Asia
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Asia
India has produced agates since as early as the 11th century. These include carnelian agates, moss agates, and dendritic agates.
Yemen is home to a variety of agate called mocha stone, named after the port city of Mocha (also spelled Mokha or Mukha) on the Red Sea. These agates likely formed in tuff deposits of Late Oligocene and Early Miocene age.
Agates have also been found in Iran, Mongolia, China, and Russia.
thumb|center|180px|Rough agates from the Gobi Desert in Mongolia
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Agate
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Australia
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Australia
Queensland agates, found in the State of Queensland, often occur in colors that are rarely found in agates from other regions, such as green and yellow-green. They formed in basaltic lava flows of the Late Permian period. Level banding is common in Queensland agates, while inclusions are uncommon. Queensland is also home to several kinds of thunder egg, which are thought to date from the Early Cretaceous period.
Agates have also been found in Tasmania and other regions of Australia.
thumb|center|215px|Queensland agate with level banding
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Agate
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Europe
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Europe
Agate was discovered in Sicily by the Greek scholar Theophrastus in 350 BC. At the time, Sicily was a colony of ancient Greece. The name "agate" comes from the Achates River, the Greek name for what is now known as the Dirillo River. Agates in Sicily formed in balsaltic lavas and pyroclastic rocks of the Pilocene epoch.
Germany is a well-known historic source of agate. Agates mined from volcanic rock of the Permian period have been processed in Idar-Oberstein since at least 1375, but possibly as early as the Roman Empire. Agates from the Idar-Oberstein area are often red and pink, but other colors have also been observed. Many museum specimens include features such as eyes, tubes, moss, plumes, and sagenite.
Scotland is an abundant source of a wide variety of agates. There are at least 50 main agate localities in Scotland. Scottish agates have been popular in jewelry for several hundred years, particularly during the Victorian era. They formed in two types of rock: andesite from the Early Devonian period and basalt from the Tertiary period. The andesite deposits are more significant and extend from Stonehaven in the northeast to just south of Ayr in the southwest. The basaltic agates are confined to the islands off the west coast of Scotland and are collectively called the Small Isles agates. The colors of Scottish agates vary, and bands may be different shades of blue, grey, purple, pink, brown, orange, or red.
Pot stones or potato stones are irregular agate nodules or geodes found in Bristol and Somerset, England. They typically consist of a reddish, banded agate surrounding a hollow cavity lined with macroscopic quartz, although some are completely filled with agate. Other varieties of agate have also been found elsewhere in England.
Agates can also be found in Wales, the Czech Republic, Poland, France, and many other European countries.
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Agate
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North America
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North America
Coldwater agates, such as the Lake Michigan cloud agate, are sedimentary agates that formed within limestone and dolomite strata of marine origin. Like volcanic agates, Coldwater agates formed from silica gels that lined pockets and seams within the bedrock. These agates are typically less colorful, with banded lines of grey and white chalcedony.
Crazy lace agate is a brightly colored lace agate from Mexico with a complex pattern, demonstrating randomized distribution of contour lines and circular droplets, scattered throughout the rock. The stone is typically colored red and white but is also seen to exhibit yellow and grey combinations as well. Crazy lace agate is a vein agate that formed in sedimentary rock of the late Cretaceous period.
Dugway geodes are a type of thunder egg found in Utah. They are typically light grey to blue and often contain hollow cavities lined with drusy quartz.
Fairburn agates are rare fortification agates named for Fairburn, South Dakota. They are sedimentary agates that originated during the Pennsylvanian period, and then weathered from their host rock and redeposited during the Oligocene epoch in parts of South Dakota and Nebraska.
Laguna agate is a brightly colored agate variety that was first discovered in Ojo Laguna, Chihuahua, Mexico. It features vibrant bands in shades of red, orange, pink, or purple. Laguna agates formed in andesite and are geologically young. They frequently contain inclusions and many exhibit parallax or shadow banding.
Lake Superior agates are believed to be the world's oldest agates; they formed as nodules in basalt up to 1.2 billion years ago during the Late Precambrian. These agates are primarily found near the shores of Lake Superior in the U.S. states of Minnesota, Michigan, and Wisconsin, and in the Canadian province of Ontario. They are not named after the lake, but rather the Lake Superior Till, the Pleistocene glacial deposit in which they are found. This deposit also extends into portions of Iowa, Nebraska, Kansas, and Missouri, and Lake Superior agates have been carried south by the Mississippi River into Arkansas and Louisiana. Lake Superior agates have bands in shades of red, orange, yellow, brown, white, and grey. They can contain a variety of structural features, including eyes, tubes, sagenite, dendrites, faults, and geodes.
Lysite agate is a vein agate named after Lysite Mountain, Wyoming. It is frequently colorful and may contain moss and plumes in addition to bands.
Nebraska blue agate is a sedimentary agate with dendritic patterns that formed during the Oligocene epoch. It can be found throughout northwestern Nebraska and southwestern South Dakota.
Oregon is known for several different varieties of agate. It is probably best known for its thunder eggs, which form in rhyolitic ash and have a brown rhyolite shell that is usually filled with blue and white agate. Holley blue agate (also spelled "Holly blue agate") is a rare lavender to blue agate found only near Holley, Oregon.
Patuxent River stone is a red and yellow form of agate only found in Maryland, where it is the state gem.
Sweetwater agates are small moss agates found in Miocene age sandstone near Sweetwater River, Wyoming. They also contain brown or black dendrites and fluoresce under UV light.
Turritella agate is a brown fossil agate formed from the remains of an extinct species of freshwater snail (Elimia tenera) with an elongated spiral shell. The name is a misnomer; it was originally thought to be the fossil of a different genus of gastropods, Turritella. It is found in the Green River Formation of Wyoming.
Other varieties of agate have also been found in nearly every U.S. state, northern Mexico, and in the Canadian provinces of Nova Scotia, Manitoba, and British Columbia.
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Agate
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South America
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South America
Brazilian agate is probably one of the largest agates. They can reach in diameter and weigh over . Brazilian agate is found primarily as nodules and geodes in decomposed volcanic ash and basalt of Late Permian age. The largest deposits are in the Brazilian state of Rio Grande do Sul, but significant amounts can also be found throughout southeastern Brazil. Some specimens can be very colorful and include features such as eyes, tubes, dendrites, and sagentite. However, most Brazilian agate that is mined is naturally pale yellow, gray, or colorless and artificially dyed before being brought to market.
Condor agates are found in the Mendoza province of Argentina. They typically have bright red and yellow fortification banding and may contain mossy or sagenitic inclusions. Other varieties of agate can also be found in the Patagonia area of Argentina, including crater agate (typically hollow nodules with black and red bands) and puma agate (agatized coral).
Uruguay was the first major source of agates in South America. Agates were discovered there in 1830, but sources in neighboring Brazil became more popular in the late 19th and 20th centuries.
Agates have also been found in Chile and Peru.
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Agate
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Uses
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Uses
Agate has long been popular as a gemstone in jewelery such as pins, brooches, necklaces, earrings, and bracelets. Agates have also historically been used in the art of hardstone carving to make knives, inkstands, seals, marbles, and other objects. Today, they are still used to make beads, decorative displays, carvings, and cabochons, as well as face-polished and tumble-polished specimens of varying size and origin. Agate collecting is a popular hobby, and agate specimens can be found in numerous gift shops, museums, galleries, and private collections.
Industrial uses of agate exploit its hardness, ability to retain a highly polished surface finish and resistance to chemical attack. Historically, it was used to make bearings for highly accurate laboratory balances and mortars and pestles to crush and mix chemicals. During the Second World War, black agate beads mined from Queensland, Australia were used in the turn and bank indicators of military aircraft.
Agates, particularly moss agates, were first used during the Stone Age to make tools such as arrow and spear points, needles, and hide scrapers. Artefacts from as early as 7000 BCE have been found in Mongolia, and the Natufian people of the Levant are known to have made knives and arrowheads from moss agate as early as 10000 BCE. Agate jewelry from Sumeria has been dated to c. 2500 BCE, and the Ancient Egyptians, Mycenaeans, and Romans all used agate in their jewelry. Archaeological recovery at the Knossos site on Crete illustrates the role of agates in Bronze Age Minoan culture.C. Michael Hogan. 2007. Knossos fieldnotes, Modern Antiquarian The ornamental use of agate was common in ancient Greece, in assorted jewelry and in the seal stones of Greek warriors.
Idar-Oberstein was a historically important location in Germany that made use of agate on an industrial scale, dating back to c. 1375 CE. Originally, locally found agates were used to make all types of objects for the European market, but it became a globalized business around the turn of the 20th century. Idar-Oberstein began to import large quantities of agate from Brazil, as ship's ballast. Making use of a variety of proprietary chemical processes, they produced colored beads that were sold around the globe.
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Agate
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Health impact
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Health impact
Respiratory diseases such as silicosis, and a higher incidence of tuberculosis among workers involved in the agate industry, have been studied in India and China.
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Agate
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See also
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See also
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Agate
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References
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References
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Agate
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External links
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External links
"Agates", School of Natural Resources, University of Nebraska-Lincoln (retrieved 27 December 2014).
Category:Gemstones
Category:Hardstone carving
Category:Silicate minerals
Category:Symbols of Florida
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Agate
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Table of Content
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short description, Etymology, Formation and properties, Varieties (by structure), Wall-banded agates, Level-banded agates, Varieties (by locality), Africa, Antarctica, Asia, Australia, Europe, North America, South America, Uses, Health impact, See also, References, External links
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Aspirin
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Short description
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Aspirin ("aspirin". Random House Webster's Unabridged Dictionary.) is the genericized trademark for acetylsalicylic acid (ASA), a nonsteroidal anti-inflammatory drug (NSAID) used to reduce pain, fever, and inflammation, and as an antithrombotic. Specific inflammatory conditions that aspirin is used to treat include Kawasaki disease, pericarditis, and rheumatic fever.
Aspirin is also used long-term to help prevent further heart attacks, ischaemic strokes, and blood clots in people at high risk. For pain or fever, effects typically begin within 30 minutes. Aspirin works similarly to other NSAIDs but also suppresses the normal functioning of platelets.
One common adverse effect is an upset stomach. More significant side effects include stomach ulcers, stomach bleeding, and worsening asthma. Bleeding risk is greater among those who are older, drink alcohol, take other NSAIDs, or are on other blood thinners. Aspirin is not recommended in the last part of pregnancy. It is not generally recommended in children with infections because of the risk of Reye syndrome. High doses may result in ringing in the ears.
A precursor to aspirin found in the bark of the willow tree (genus Salix) has been used for its health effects for at least 2,400 years. In 1853, chemist Charles Frédéric Gerhardt treated the medicine sodium salicylate with acetyl chloride to produce acetylsalicylic acid for the first time. Over the next 50 years, other chemists, mostly of the German company Bayer, established the chemical structure and devised more efficient production methods. Felix Hoffmann (or Arthur Eichengrün) of Bayer was the first to produce acetylsalicylic acid in a pure, stable form in 1897. By 1899, Bayer had dubbed this drug Aspirin and was selling it globally.
Aspirin is available without medical prescription as a proprietary or generic medication in most jurisdictions. It is one of the most widely used medications globally, with an estimated (50 to 120 billion pills) consumed each year, and is on the World Health Organization's List of Essential Medicines. In 2022, it was the 36th most commonly prescribed medication in the United States, with more than 16million prescriptions.
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Aspirin
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Brand vs. generic name
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Brand vs. generic name
In 1897, scientists at the Bayer company began studying acetylsalicylic acid as a less-irritating replacement medication for common salicylate medicines. By 1899, Bayer had named it "Aspirin" and was selling it around the world.
Aspirin's popularity grew over the first half of the 20th century, leading to competition between many brands and formulations. The word Aspirin was Bayer's brand name; however, its rights to the trademark were lost or sold in many countries. The name is ultimately a blend of the prefix a(cetyl) + spir Spiraea, the meadowsweet plant genus from which the acetylsalicylic acid was originally derived at Bayer + -in, the common chemical suffix.
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Aspirin
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Chemical properties
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Chemical properties
Aspirin decomposes rapidly in solutions of ammonium acetate or the acetates, carbonates, citrates, or hydroxides of the alkali metals. It is stable in dry air, but gradually hydrolyses in contact with moisture to acetic and salicylic acids. In solution with alkalis, the hydrolysis proceeds rapidly and the clear solutions formed may consist entirely of acetate and salicylate.
Like flour mills, factories producing aspirin tablets must control the amount of the powder that becomes airborne inside the building, because the powder-air mixture can be explosive. The National Institute for Occupational Safety and Health (NIOSH) has set a recommended exposure limit in the United States of 5mg/m3 (time-weighted average). In 1989, the Occupational Safety and Health Administration (OSHA) set a legal permissible exposure limit for aspirin of 5mg/m3, but this was vacated by the AFL-CIO v. OSHA decision in 1993.
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Aspirin
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Synthesis
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Synthesis
The synthesis of aspirin is classified as an esterification reaction. Salicylic acid is treated with acetic anhydride, an acid derivative, causing a chemical reaction that turns salicylic acid's hydroxyl group into an ester group (R-OH → R-OCOCH3). This process yields aspirin and acetic acid, which is considered a byproduct of this reaction. Small amounts of sulfuric acid (and occasionally phosphoric acid) are almost always used as a catalyst. This method is commonly demonstrated in undergraduate teaching labs.
class=skin-invert-image|thumb|Aspirin synthesis|center|490pxReaction between acetic acid and salicylic acid can also form aspirin but this esterification reaction is reversible and the presence of water can lead to hydrolysis of the aspirin. So, an anhydrous reagent is preferred.
Reaction mechanism
class=skin-invert-image|thumb|center|Acetylation of salicylic acid, mechanism|800px
Formulations containing high concentrations of aspirin often smell like vinegar because aspirin can decompose through hydrolysis in moist conditions, yielding salicylic and acetic acids.
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Aspirin
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Physical properties
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Physical properties
Aspirin, an acetyl derivative of salicylic acid, is a white, crystalline, weakly acidic substance that melts at , and decomposes around . Its acid dissociation constant (pKa) is 3.5 at .
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Aspirin
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Polymorphism
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Polymorphism
Polymorphism, or the ability of a substance to form more than one crystal structure, is important in the development of pharmaceutical ingredients. Many drugs receive regulatory approval for only a single crystal form or polymorph.
Until 2005, there was only one proven polymorph of aspirin (Form I), though the existence of another polymorph was debated since the 1960s, and one report from 1981 reported that when crystallized in the presence of aspirin anhydride, the diffractogram of aspirin has weak additional peaks. Though at the time it was dismissed as mere impurity, it was, in retrospect, Form II aspirin.
Form II was reported in 2005, found after attempted co-crystallization of aspirin and levetiracetam from hot acetonitrile.
In form I, pairs of aspirin molecules form centrosymmetric dimers through the acetyl groups with the (acidic) methyl proton to carbonyl hydrogen bonds. In form II, each aspirin molecule forms the same hydrogen bonds, but with two neighbouring molecules instead of one. With respect to the hydrogen bonds formed by the carboxylic acid groups, both polymorphs form identical dimer structures. The aspirin polymorphs contain identical 2-dimensional sections and are therefore more precisely described as polytypes.
Pure Form II aspirin could be prepared by seeding the batch with aspirin anhydrate in 15% weight.
Form III was reported in 2015 by compressing form I above 2 GPa, but it reverts back to Form I when pressure is removed. Form IV was reported in 2017. It is stable at ambient conditions.
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Aspirin
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Mechanism of action
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Mechanism of action
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Aspirin
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Discovery of the mechanism
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Discovery of the mechanism
In 1971, British pharmacologist John Robert Vane, then employed by the Royal College of Surgeons in London, showed aspirin suppressed the production of prostaglandins and thromboxanes. For this discovery he was awarded the 1982 Nobel Prize in Physiology or Medicine, jointly with Sune Bergström and Bengt Ingemar Samuelsson.
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Aspirin
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Prostaglandins and thromboxanes
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Prostaglandins and thromboxanes
Aspirin's ability to suppress the production of prostaglandins and thromboxanes is due to its irreversible inactivation of the cyclooxygenase (COX; officially known as prostaglandin-endoperoxide synthase, PTGS) enzyme required for prostaglandin and thromboxane synthesis. Aspirin acts as an acetylating agent where an acetyl group is covalently attached to a serine residue in the active site of the COX enzyme (Suicide inhibition). This makes aspirin different from other NSAIDs (such as diclofenac and ibuprofen), which are reversible inhibitors.
Low-dose aspirin use irreversibly blocks the formation of thromboxane A2 in platelets, producing an inhibitory effect on platelet aggregation during the lifetime of the affected platelet (8–9 days). This antithrombotic property makes aspirin useful for reducing the incidence of heart attacks in people who have had a heart attack, unstable angina, ischemic stroke or transient ischemic attack. 40mg of aspirin a day is able to inhibit a large proportion of maximum thromboxane A2 release provoked acutely, with the prostaglandin I2 synthesis being little affected; however, higher doses of aspirin are required to attain further inhibition.
Prostaglandins, local hormones produced in the body, have diverse effects, including the transmission of pain information to the brain, modulation of the hypothalamic thermostat, and inflammation. Thromboxanes are responsible for the aggregation of platelets that form blood clots. Heart attacks are caused primarily by blood clots, and low doses of aspirin are seen as an effective medical intervention to prevent a second acute myocardial infarction.
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Aspirin
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COX-1 and COX-2 inhibition
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COX-1 and COX-2 inhibition
At least two different types of cyclooxygenases, COX-1 and COX-2, are acted on by aspirin. Aspirin irreversibly inhibits COX-1 and modifies the enzymatic activity of COX-2. COX-2 normally produces prostanoids, most of which are proinflammatory. Aspirin-modified COX-2 (aka prostaglandin-endoperoxide synthase 2 or PTGS2) produces epi-lipoxins, most of which are anti-inflammatory. Newer NSAID drugs, COX-2 inhibitors (coxibs), have been developed to inhibit only COX-2, with the intent to reduce the incidence of gastrointestinal side effects.
Several COX-2 inhibitors, such as rofecoxib (Vioxx), have been withdrawn from the market, after evidence emerged that COX-2 inhibitors increase the risk of heart attack and stroke. Endothelial cells lining the microvasculature in the body are proposed to express COX-2, and, by selectively inhibiting COX-2, prostaglandin production (specifically, PGI2; prostacyclin) is downregulated with respect to thromboxane levels, as COX-1 in platelets is unaffected. Thus, the protective anticoagulative effect of PGI2 is removed, increasing the risk of thrombus and associated heart attacks and other circulatory problems. Since platelets have no DNA, they are unable to synthesize new COX-1 once aspirin has irreversibly inhibited the enzyme, an important difference as compared with reversible inhibitors.
Furthermore, aspirin, while inhibiting the ability of COX-2 to form pro-inflammatory products such as the prostaglandins, converts this enzyme's activity from a prostaglandin-forming cyclooxygenase to a lipoxygenase-like enzyme: aspirin-treated COX-2 metabolizes a variety of polyunsaturated fatty acids to hydroperoxy products which are then further metabolized to specialized proresolving mediators such as the aspirin-triggered lipoxins(15-epilipoxin-A4/B4), aspirin-triggered resolvins, and aspirin-triggered maresins. These mediators possess potent anti-inflammatory activity. It is proposed that this aspirin-triggered transition of COX-2 from cyclooxygenase to lipoxygenase activity and the consequential formation of specialized proresolving mediators contributes to the anti-inflammatory effects of aspirin.
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Aspirin
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Additional mechanisms
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Additional mechanisms
Aspirin has been shown to have at least three additional modes of action. It uncouples oxidative phosphorylation in cartilaginous (and hepatic) mitochondria, by diffusing from the inner membrane space as a proton carrier back into the mitochondrial matrix, where it ionizes once again to release protons. Aspirin buffers and transports the protons. When high doses are given, it may actually cause fever, owing to the heat released from the electron transport chain, as opposed to the antipyretic action of aspirin seen with lower doses. In addition, aspirin induces the formation of NO-radicals in the body, which have been shown in mice to have an independent mechanism of reducing inflammation. This reduced leukocyte adhesion is an important step in the immune response to infection; however, evidence is insufficient to show aspirin helps to fight infection. More recent data also suggest salicylic acid and its derivatives modulate signalling through NF-κB. NF-κB, a transcription factor complex, plays a central role in many biological processes, including inflammation.
Aspirin is readily broken down in the body to salicylic acid, which itself has anti-inflammatory, antipyretic, and analgesic effects. In 2012, salicylic acid was found to activate AMP-activated protein kinase, which has been suggested as a possible explanation for some of the effects of both salicylic acid and aspirin. The acetyl portion of the aspirin molecule has its own targets. Acetylation of cellular proteins is a well-established phenomenon in the regulation of protein function at the post-translational level. Aspirin is able to acetylate several other targets in addition to COX isoenzymes. These acetylation reactions may explain many hitherto unexplained effects of aspirin.
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Aspirin
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Formulations
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Formulations
Aspirin is produced in many formulations, with some differences in effect. In particular, aspirin can cause gastrointestinal bleeding, and formulations are sought which deliver the benefits of aspirin while mitigating harmful bleeding. Formulations may be combined (e.g., buffered + vitamin C).
Tablets, typically of about 75–100 mg and 300–320 mg of immediate-release aspirin (IR-ASA).
Dispersible tablets.
Enteric-coated tablets.
Buffered formulations containing aspirin with one of many buffering agents.
Formulations of aspirin with vitamin C (ASA-VitC)
A phospholipid-aspirin complex liquid formulation, PL-ASA. the phospholipid coating was being trialled to determine if it caused less gastrointestinal damage.
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Aspirin
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Pharmacokinetics
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Pharmacokinetics
Acetylsalicylic acid is a weak acid, and very little of it is ionized in the stomach after oral administration. Acetylsalicylic acid is quickly absorbed through the cell membrane in the acidic conditions of the stomach. The increased pH and larger surface area of the small intestine causes aspirin to be absorbed more slowly there, as more of it is ionized. Owing to the formation of concretions, aspirin is absorbed much more slowly during overdose, and plasma concentrations can continue to rise for up to 24 hours after ingestion.
About 50–80% of salicylate in the blood is bound to human serum albumin, while the rest remains in the active, ionized state; protein binding is concentration-dependent. Saturation of binding sites leads to more free salicylate and increased toxicity. The volume of distribution is 0.1–0.2 L/kg. Acidosis increases the volume of distribution because of enhancement of tissue penetration of salicylates.
As much as 80% of therapeutic doses of salicylic acid is metabolized in the liver. Conjugation with glycine forms salicyluric acid, and with glucuronic acid to form two different glucuronide esters. The conjugate with the acetyl group intact is referred to as the acyl glucuronide; the deacetylated conjugate is the phenolic glucuronide. These metabolic pathways have only a limited capacity. Small amounts of salicylic acid are also hydroxylated to gentisic acid. With large salicylate doses, the kinetics switch from first-order to zero-order, as metabolic pathways become saturated and renal excretion becomes increasingly important.
Salicylates are excreted mainly by the kidneys as salicyluric acid (75%), free salicylic acid (10%), salicylic phenol (10%), and acyl glucuronides (5%), gentisic acid (< 1%), and 2,3-dihydroxybenzoic acid. When small doses (less than 250mg in an adult) are ingested, all pathways proceed by first-order kinetics, with an elimination half-life of about 2.0 h to 4.5 h. When higher doses of salicylate are ingested (more than 4 g), the half-life becomes much longer (15 h to 30 h), because the biotransformation pathways concerned with the formation of salicyluric acid and salicyl phenolic glucuronide become saturated. Renal excretion of salicylic acid becomes increasingly important as the metabolic pathways become saturated, because it is extremely sensitive to changes in urinary pH. A 10- to 20-fold increase in renal clearance occurs when urine pH is increased from 5 to 8. The use of urinary alkalinization exploits this particular aspect of salicylate elimination. It was found that short-term aspirin use in therapeutic doses might precipitate reversible acute kidney injury when the patient was ill with glomerulonephritis or cirrhosis. Aspirin for some patients with chronic kidney disease and some children with congestive heart failure was contraindicated.
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Aspirin
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History
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History
thumb|left|1923 advertisement
Medicines made from willow and other salicylate-rich plants appear in clay tablets from ancient Sumer as well as the Ebers Papyrus from ancient Egypt. Hippocrates referred to the use of salicylic tea to reduce fevers around 400 BC, and willow bark preparations were part of the pharmacopoeia of Western medicine in classical antiquity and the Middle Ages. Willow bark extract became recognized for its specific effects on fever, pain, and inflammation in the mid-eighteenth century after the Rev Edward Stone of Chipping Norton, Oxfordshire, noticed that the bitter taste of willow bark resembled the taste of the bark of the cinchona tree, known as "Peruvian bark", which was used successfully in Peru to treat a variety of ailments. Stone experimented with preparations of powdered willow bark on people in Chipping Norton for five years and found it to be as effective as Peruvian bark and a cheaper domestic version. In 1763 he sent a report of his findings to the Royal Society in London. By the nineteenth century, pharmacists were experimenting with and prescribing a variety of chemicals related to salicylic acid, the active component of willow extract.
thumb|Old package. "Export from Germany is prohibited"
In 1853, chemist Charles Frédéric Gerhardt treated sodium salicylate with acetyl chloride to produce acetylsalicylic acid for the first time; in the second half of the 19th century, other academic chemists established the compound's chemical structure and devised more efficient methods of synthesis. In 1897, scientists at the drug and dye firm Bayer began investigating acetylsalicylic acid as a less-irritating replacement for standard common salicylate medicines, and identified a new way to synthesize it. That year, Felix Hoffmann (or Arthur Eichengrün) of Bayer was the first to produce acetylsalicylic acid in a pure, stable form.
Salicylic acid had been extracted in 1838 from the herb meadowsweet, whose German name, Spirsäure, was the basis for naming the newly synthesized drug, which, by 1899, Bayer was selling globally. The word Aspirin was Bayer's brand name, rather than the generic name of the drug; however, Bayer's rights to the trademark were lost or sold in many countries. Aspirin's popularity grew over the first half of the 20th century, leading to fierce competition with the proliferation of aspirin brands and products.
Aspirin's popularity declined after the development of acetaminophen/paracetamol in 1956 and ibuprofen in 1962. In the 1960s and 1970s, John Vane and others discovered the basic mechanism of aspirin's effects, while clinical trials and other studies from the 1960s to the 1980s established aspirin's efficacy as an anti-clotting agent that reduces the risk of clotting diseases. The initial large studies on the use of low-dose aspirin to prevent heart attacks that were published in the 1970s and 1980s helped spur reform in clinical research ethics and guidelines for human subject research and US federal law, and are often cited as examples of clinical trials that included only men, but from which people drew general conclusions that did not hold true for women.
Aspirin sales revived considerably in the last decades of the 20th century, and remain strong in the 21st century with widespread use as a preventive treatment for heart attacks and strokes.
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Aspirin
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Trademark
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Trademark
Bayer lost its trademark for Aspirin in the United States and some other countries in actions taken between 1918 and 1921 because it had failed to use the name for its own product correctly and had for years allowed the use of "Aspirin" by other manufacturers without defending the intellectual property rights. Today, aspirin is a generic trademark in many countries. Aspirin, with a capital "A", remains a registered trademark of Bayer in Germany, Canada, Mexico, and in over 80 other countries, for acetylsalicylic acid in all markets, but using different packaging and physical aspects for each.
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Aspirin
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Compendial status
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Compendial status
United States Pharmacopeia
British Pharmacopoeia
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Aspirin
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Medical use
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Medical use
Aspirin is used in the treatment of a number of conditions, including fever, pain, rheumatic fever, and inflammatory conditions, such as rheumatoid arthritis, pericarditis, and Kawasaki disease. Lower doses of aspirin have also been shown to reduce the risk of death from a heart attack, or the risk of stroke in people who are at high risk or who have cardiovascular disease, but not in elderly people who are otherwise healthy. There is evidence that aspirin is effective at preventing colorectal cancer, though the mechanisms of this effect are unclear.
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Aspirin
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Pain
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Pain
Aspirin is an effective analgesic for acute pain, although it is generally considered inferior to ibuprofen because aspirin is more likely to cause gastrointestinal bleeding. Aspirin is generally ineffective for those pains caused by muscle cramps, bloating, gastric distension, or acute skin irritation. As with other NSAIDs, combinations of aspirin and caffeine provide slightly greater pain relief than aspirin alone. Effervescent formulations of aspirin relieve pain faster than aspirin in tablets, which makes them useful for the treatment of migraines. Topical aspirin may be effective for treating some types of neuropathic pain.
Aspirin, either by itself or in a combined formulation, effectively treats certain types of a headache, but its efficacy may be questionable for others. Secondary headaches, meaning those caused by another disorder or trauma, should be promptly treated by a medical provider. Among primary headaches, the International Classification of Headache Disorders distinguishes between tension headache (the most common), migraine, and cluster headache. Aspirin or other over-the-counter analgesics are widely recognized as effective for the treatment of tension headaches. Aspirin, especially as a component of an aspirin/paracetamol/caffeine combination, is considered a first-line therapy in the treatment of migraine, and comparable to lower doses of sumatriptan. It is most effective at stopping migraines when they are first beginning.
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Aspirin
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Fever
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Fever
Like its ability to control pain, aspirin's ability to control fever is due to its action on the prostaglandin system through its irreversible inhibition of COX. Although aspirin's use as an antipyretic in adults is well established, many medical societies and regulatory agencies, including the American Academy of Family Physicians, the American Academy of Pediatrics, and the Food and Drug Administration, strongly advise against using aspirin for the treatment of fever in children because of the risk of Reye's syndrome, a rare but often fatal illness associated with the use of aspirin or other salicylates in children during episodes of viral or bacterial infection. Because of the risk of Reye's syndrome in children, in 1986, the US Food and Drug Administration (FDA) required labeling on all aspirin-containing medications advising against its use in children and teenagers.
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Aspirin
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Inflammation
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Inflammation
Aspirin is used as an anti-inflammatory agent for both acute and long-term inflammation, as well as for the treatment of inflammatory diseases, such as rheumatoid arthritis.
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Aspirin
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Heart attacks and strokes
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Heart attacks and strokes
Aspirin is an important part of the treatment of those who have had a heart attack. It is generally not recommended for routine use by people with no other health problems, including those over the age of 70.
The 2009 Antithrombotic Trialists' Collaboration published in Lancet evaluated the efficacy and safety of low dose aspirin in secondary prevention. In those with prior ischaemic stroke or acute myocardial infarction, daily low dose aspirin was associated with a 19% relative risk reduction of serious cardiovascular events (non-fatal myocardial infarction, non-fatal stroke, or vascular death). This did come at the expense of a 0.19% absolute risk increase in gastrointestinal bleeding; however, the benefits outweigh the hazard risk in this case. Data from previous trials have suggested that weight-based dosing of aspirin has greater benefits in primary prevention of cardiovascular outcomes. However, more recent trials were not able to replicate similar outcomes using low dose aspirin in low body weight (<70 kg) in specific subset of population studied i.e. elderly and diabetic population, and more evidence is required to study the effect of high dose aspirin in high body weight (≥70 kg).
After percutaneous coronary interventions (PCIs), such as the placement of a coronary artery stent, a U.S. Agency for Healthcare Research and Quality guideline recommends that aspirin be taken indefinitely. Frequently, aspirin is combined with an ADP receptor inhibitor, such as clopidogrel, prasugrel, or ticagrelor to prevent blood clots. This is called dual antiplatelet therapy (DAPT). Duration of DAPT was advised in the United States and European Union guidelines after the CURE and PRODIGY studies. In 2020, the systematic review and network meta-analysis from Khan et al. showed promising benefits of short-term (< 6 months) DAPT followed by P2Y12 inhibitors in selected patients, as well as the benefits of extended-term (> 12 months) DAPT in high risk patients. In conclusion, the optimal duration of DAPT after PCIs should be personalized after outweighing each patient's risks of ischemic events and risks of bleeding events with consideration of multiple patient-related and procedure-related factors. Moreover, aspirin should be continued indefinitely after DAPT is complete.
The status of the use of aspirin for the primary prevention in cardiovascular disease is conflicting and inconsistent, with recent changes from previously recommending it widely decades ago, and that some referenced newer trials in clinical guidelines show less of benefit of adding aspirin alongside other anti-hypertensive and cholesterol lowering therapies. The ASCEND study demonstrated that in high-bleeding risk diabetics with no prior cardiovascular disease, there is no overall clinical benefit (12% decrease in risk of ischaemic events v/s 29% increase in GI bleeding) of low dose aspirin in preventing the serious vascular events over a period of 7.4 years. Similarly, the results of the ARRIVE study also showed no benefit of same dose of aspirin in reducing the time to first cardiovascular outcome in patients with moderate risk of cardiovascular disease over a period of five years. Aspirin has also been suggested as a component of a polypill for prevention of cardiovascular disease. Complicating the use of aspirin for prevention is the phenomenon of aspirin resistance. For people who are resistant, aspirin's efficacy is reduced. Some authors have suggested testing regimens to identify people who are resistant to aspirin.
As of , the United States Preventive Services Task Force (USPSTF) determined that there was a "small net benefit" for patients aged 40–59 with a 10% or greater 10-year cardiovascular disease (CVD) risk, and "no net benefit" for patients aged over 60. Determining the net benefit was based on balancing the risk reduction of taking aspirin for heart attacks and ischaemic strokes, with the increased risk of gastrointestinal bleeding, intracranial bleeding, and hemorrhagic strokes. Their recommendations state that age changes the risk of the medicine, with the magnitude of the benefit of aspirin coming from starting at a younger age, while the risk of bleeding, while small, increases with age, particular for adults over 60, and can be compounded by other risk factors such as diabetes and a history of gastrointestinal bleeding. As a result, the USPSTF suggests that "people ages 40 to 59 who are at higher risk for CVD should decide with their clinician whether to start taking aspirin; people 60 or older should not start taking aspirin to prevent a first heart attack or stroke." Primary prevention guidelines from made by the American College of Cardiology and the American Heart Association state they might consider aspirin for patients aged 40–69 with a higher risk of atherosclerotic CVD, without an increased bleeding risk, while stating they would not recommend aspirin for patients aged over 70 or adults of any age with an increased bleeding risk. They state a CVD risk estimation and a risk discussion should be done before starting on aspirin, while stating aspirin should be used "infrequently in the routine primary prevention of (atherosclerotic CVD) because of lack of net benefit". As of , the European Society of Cardiology made similar recommendations; considering aspirin specifically to patients aged less than 70 at high or very high CVD risk, without any clear contraindications, on a case-by-case basis considering both ischemic risk and bleeding risk.
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Aspirin
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Cancer prevention
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Cancer prevention
Aspirin may reduce the overall risk of both getting cancer and dying from cancer. There is substantial evidence for lowering the risk of colorectal cancer (CRC), but aspirin must be taken for at least 10–20 years to see this benefit. It may also slightly reduce the risk of endometrial cancer and prostate cancer.
Some conclude the benefits are greater than the risks due to bleeding in those at average risk. Others are unclear if the benefits are greater than the risk. Given this uncertainty, the 2007 United States Preventive Services Task Force (USPSTF) guidelines on this topic recommended against the use of aspirin for prevention of CRC in people with average risk. Nine years later however, the USPSTF issued a grade B recommendation for the use of low-dose aspirin (75 to 100mg/day) "for the primary prevention of CVD [cardiovascular disease] and CRC in adults 50 to 59 years of age who have a 10% or greater 10-year CVD risk, are not at increased risk for bleeding, have a life expectancy of at least 10 years, and are willing to take low-dose aspirin daily for at least 10 years".
A meta-analysis through 2019 said that there was an association between taking aspirin and lower risk of cancer of the colorectum, esophagus, and stomach.
In 2021, the U.S. Preventive services Task Force raised questions about the use of aspirin in cancer prevention. It notes the results of the 2018 ASPREE (Aspirin in Reducing Events in the Elderly) Trial, in which the risk of cancer-related death was higher in the aspirin-treated group than in the placebo group.
In 2025, a group of scientists at the University of Cambridge found that aspirin stimulates the immune system to reduce cancer metastasis. They found that a protein called ARHGEF1 suppresses T cells, that are required for attacking metastatic cancer cells. Aspirin appeared to counteract this suppression by targeting a clotting factor called thromboxane A2 (TXA2), which activates ARHGEF1, thus preventing it from suppressing the T cells. The researchers called the discovery a "Eureka moment". It was reported that the findings could lead to a more targeted use for aspirin in cancer research. It was also said that taking self-medicating with aspirin should not be done yet due to its potential side effects until clinical trials were held.
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Aspirin
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Psychiatry
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Psychiatry
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Aspirin
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Bipolar disorder
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Bipolar disorder
Aspirin, along with several other agents with anti-inflammatory properties, has been repurposed as an add-on treatment for depressive episodes in subjects with bipolar disorder in light of the possible role of inflammation in the pathogenesis of severe mental disorders. A 2022 systematic review concluded that aspirin exposure reduced the risk of depression in a pooled cohort of three studies (HR 0.624, 95% CI: 0.0503, 1.198, P=0.033). However, further high-quality, longer-duration, double-blind randomized controlled trials (RCTs) are needed to determine whether aspirin is an effective add-on treatment for bipolar depression. Thus, notwithstanding the biological rationale, the clinical perspectives of aspirin and anti-inflammatory agents in the treatment of bipolar depression remain uncertain.
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Aspirin
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Dementia
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Dementia
Although cohort and longitudinal studies have shown low-dose aspirin has a greater likelihood of reducing the incidence of dementia, numerous randomized controlled trials have not validated this.
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Aspirin
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Schizophrenia
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Schizophrenia
Some researchers have speculated the anti-inflammatory effects of aspirin may be beneficial for schizophrenia. Small trials have been conducted but evidence remains lacking.
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Aspirin
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Other uses
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Other uses
Aspirin is a first-line treatment for the fever and joint-pain symptoms of acute rheumatic fever. The therapy often lasts for one to two weeks, and is rarely indicated for longer periods. After fever and pain have subsided, the aspirin is no longer necessary, since it does not decrease the incidence of heart complications and residual rheumatic heart disease. Naproxen has been shown to be as effective as aspirin and less toxic, but due to the limited clinical experience, naproxen is recommended only as a second-line treatment.
Along with rheumatic fever, Kawasaki disease remains one of the few indications for aspirin use in children in spite of a lack of high quality evidence for its effectiveness.
Low-dose aspirin supplementation has moderate benefits when used for prevention of pre-eclampsia. This benefit is greater when started in early pregnancy.
Aspirin has also demonstrated anti-tumoral effects, via inhibition of the PTTG1 gene, which is often overexpressed in tumors.
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Aspirin
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Resistance
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Resistance
For some people, aspirin does not have as strong an effect on platelets as for others, an effect known as aspirin-resistance or insensitivity. One study has suggested women are more likely to be resistant than men, and a different, aggregate study of 2,930 people found 28% were resistant.
A study in 100 Italian people found, of the apparent 31% aspirin-resistant subjects, only 5% were truly resistant, and the others were noncompliant.
Another study of 400 healthy volunteers found no subjects who were truly resistant, but some had "pseudoresistance, reflecting delayed and reduced drug absorption".
Meta-analysis and systematic reviews have concluded that laboratory confirmed aspirin resistance confers increased rates of poorer outcomes in cardiovascular and neurovascular diseases. Although the majority of research conducted has surrounded cardiovascular and neurovascular, there is emerging research into the risk of aspirin resistance after orthopaedic surgery where aspirin is used for venous thromboembolism prophylaxis. Aspirin resistance in orthopaedic surgery, specifically after total hip and knee arthroplasties, is of interest as risk factors for aspirin resistance are also risk factors for venous thromboembolisms and osteoarthritis; the sequelae of requiring a total hip or knee arthroplasty. Some of these risk factors include obesity, advancing age, diabetes mellitus, dyslipidemia and inflammatory diseases.
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Aspirin
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Dosages
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Dosages
Adult aspirin tablets are produced in standardised sizes, which vary slightly from country to country, for example 300mg in Britain and 325mg in the United States. Smaller doses are based on these standards, e.g., 75mg and 81mg tablets. The 81 mg tablets are commonly called "baby aspirin" or "baby-strength", because they were originallybut no longerintended to be administered to infants and children. No medical significance occurs due to the slight difference in dosage between the 75mg and the 81mg tablets. The dose required for benefit appears to depend on a person's weight. For those weighing less than , low dose is effective for preventing cardiovascular disease; for patients above this weight, higher doses are required.
In general, for adults, doses are taken four times a day for fever or arthritis, with doses near the maximal daily dose used historically for the treatment of rheumatic fever. For the prevention of myocardial infarction (MI) in someone with documented or suspected coronary artery disease, much lower doses are taken once daily.
March 2009 recommendations from the USPSTF on the use of aspirin for the primary prevention of coronary heart disease encourage men aged 45–79 and women aged 55–79 to use aspirin when the potential benefit of a reduction in MI for men or stroke for women outweighs the potential harm of an increase in gastrointestinal hemorrhage. The WHI study of postmenopausal women found that aspirin resulted in a 25% lower risk of death from cardiovascular disease and a 14% lower risk of death from any cause, though there was no significant difference between 81mg and 325mg aspirin doses. The 2021 ADAPTABLE study also showed no significant difference in cardiovascular events or major bleeding between 81mg and 325mg doses of aspirin in patients (both men and women) with established cardiovascular disease.
Low-dose aspirin use was also associated with a trend toward lower risk of cardiovascular events, and lower aspirin doses (75 or 81mg/day) may optimize efficacy and safety for people requiring aspirin for long-term prevention.
In children with Kawasaki disease, aspirin is taken at dosages based on body weight, initially four times a day for up to two weeks and then at a lower dose once daily for a further six to eight weeks.
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Aspirin
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Adverse effects
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Adverse effects
In October 2020, the US Food and Drug Administration (FDA) required the drug label to be updated for all nonsteroidal anti-inflammatory medications to describe the risk of kidney problems in unborn babies that result in low amniotic fluid. They recommend avoiding NSAIDs in pregnant women at 20 weeks or later in pregnancy. One exception to the recommendation is the use of low-dose 81mg aspirin at any point in pregnancy under the direction of a health care professional.
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Aspirin
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Contraindications
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Contraindications
Aspirin should not be taken by people who are allergic to ibuprofen or naproxen, or who have salicylate intolerance or a more generalized drug intolerance to NSAIDs, and caution should be exercised in those with asthma or NSAID-precipitated bronchospasm. Owing to its effect on the stomach lining, manufacturers recommend people with peptic ulcers, mild diabetes, or gastritis seek medical advice before using aspirin. Even if none of these conditions is present, the risk of stomach bleeding is still increased when aspirin is taken with alcohol or warfarin. People with hemophilia or other bleeding tendencies should not take aspirin or other salicylates. Aspirin is known to cause hemolytic anemia in people who have the genetic disease glucose-6-phosphate dehydrogenase deficiency, particularly in large doses and depending on the severity of the disease. Use of aspirin during dengue fever is not recommended owing to increased bleeding tendency. Aspirin taken at doses of ≤325 mg and ≤100 mg per day for ≥2 days can increase the odds of suffering a gout attack by 81% and 91% respectively. This effect may potentially be worsened by high purine diets, diuretics, and kidney disease, but is eliminated by the urate lowering drug allopurinol. Daily low dose aspirin does not appear to worsen kidney function. Aspirin may reduce cardiovascular risk in those without established cardiovascular disease in people with moderate CKD, without significantly increasing the risk of bleeding. Aspirin should not be given to children or adolescents under the age of 16 to control cold or influenza symptoms, as this has been linked with Reye's syndrome.
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Aspirin
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Gastrointestinal
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Gastrointestinal
Aspirin increases the risk of upper gastrointestinal bleeding. Enteric coating on aspirin may be used in manufacturing to prevent release of aspirin into the stomach to reduce gastric harm, but enteric coating does not reduce gastrointestinal bleeding risk. Enteric-coated aspirin may not be as effective at reducing blood clot risk. Combining aspirin with other NSAIDs has been shown to further increase the risk of gastrointestinal bleeding. Using aspirin in combination with clopidogrel or warfarin also increases the risk of upper gastrointestinal bleeding.
Blockade of COX-1 by aspirin apparently results in the upregulation of COX-2 as part of a gastric defense. There is no clear evidence that simultaneous use of a COX-2 inhibitor with aspirin may increase the risk of gastrointestinal injury.
"Buffering" is an additional method used with the intent to mitigate gastrointestinal bleeding, such as by preventing aspirin from concentrating in the walls of the stomach, although the benefits of buffered aspirin are disputed. Almost any buffering agent used in antacids can be used; Bufferin, for example, uses magnesium oxide. Other preparations use calcium carbonate. Gas-forming agents in effervescent tablet and powder formulations can also double as a buffering agent, one example being sodium bicarbonate, used in Alka-Seltzer.
Taking vitamin C with aspirin has been investigated as a method of protecting the stomach lining. In trials vitamin C-releasing aspirin (ASA-VitC) or a buffered aspirin formulation containing vitamin C was found to cause less stomach damage than aspirin alone.
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Aspirin
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Retinal vein occlusion
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Retinal vein occlusion
It is a widespread habit among eye specialists (ophthalmologists) to prescribe aspirin as an add-on medication for patients with retinal vein occlusion (RVO), such as central retinal vein occlusion (CRVO) and branch retinal vein occlusion (BRVO). The reason of this widespread use is the evidence of its proven effectiveness in major systemic venous thrombotic disorders, and it has been assumed that may be similarly beneficial in various types of retinal vein occlusion.
However, a large-scale investigation based on data of nearly 700 patients showed "that aspirin or other antiplatelet aggregating agents or anticoagulants adversely influence the visual outcome in patients with CRVO and hemi-CRVO, without any evidence of protective or beneficial effect". Several expert groups, including the Royal College of Ophthalmologists, recommended against the use of antithrombotic drugs (incl. aspirin) for patients with RVO.
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