Hans Spemann ( German pronunciation: [ˈhans ˈʃpeːˌman] ; 27 June 1869 – 9 September 1941) was a German embryologist who was awarded a Nobel Prize in Physiology or Medicine in 1935 for his student Hilde Mangold 's discovery of the effect now known as embryonic induction , an influence, exercised by various parts of the embryo , that directs the development of groups of cells into particular tissues and organs. Spemann added his name as an author to Hilde Mangold's dissertation (although she objected) and won a Nobel Prize for her work.
160-673: Hans Spemann was born in Stuttgart , the eldest son of publisher Wilhelm Spemann and his wife Lisinka, née Hoffman. After he left school in 1888 he spent a year in his father's business, then, in 1889–1890, he did military service in the Kassel Hussars followed by a short time as a bookseller in Hamburg. In 1891 he entered the University of Heidelberg where he studied medicine, taking his preliminary examination in 1893. There he met
320-437: A being itself, it is its own entity. The countries that believe this have created a 14-day rule in which it is illegal to study or experiment on a human embryo after the 14-day period in vitro . Research has been conducted on the first 14 days of an embryo, but no known studies have been done after the 14 days. With the rule in place, mice embryos are used understand the development after 14 days; however, there are differences in
480-479: A clinician, to move to the Zoological Institute at the University of Würzburg , where he remained as a lecturer until 1908. His degree in zoology, botany, and physics, awarded in 1895, followed study under Theodor Boveri , Julius von Sachs and Wilhelm Röntgen . For his Ph.D. thesis under Boveri, Spemann studied cell lineage in the parasitic worm Strongylus paradoxus , for his teaching diploma,
640-601: A derivation from a Gaulish *kondâti- "confluence". In AD 950, Duke Liudolf of Swabia , son of the current Holy Roman Emperor Otto I , decided to establish a stud farm for his cavalry during the Hungarian invasions of Europe on a widened area of the Nesenbach river valley 5 km (3.1 mi) south of the old Roman castrum. The land and title of Duke of Swabia remained in Liudolf's hands until his rebellion
800-400: A laboratory. The process of in vitro fertilization is when mature eggs are removed from the ovaries and are placed in a cultured medium where they are fertilized by sperm. In the culture the embryo will form. 14 days after fertilization the primitive streak forms. The formation of the primitive streak has been known to some countries as "human individuality". This means that the embryo is now
960-462: A member of the Württemberg royal family. In the late 1970s, the municipal district of Stammheim was centre stage to one of the most controversial periods of German post-war history. Stammheim Prison , built from 1959 to 1963, came to be the place of incarceration for Ulrike Meinhof , Andreas Baader , Gudrun Ensslin , and Jan-Carl Raspe , members of a communist terrorist organization known as
1120-401: A mesh of isolated cells, such as mesenchyme . Although gastrulation patterns exhibit enormous variation throughout the animal kingdom, they are unified by the five basic types of cell movements that occur during gastrulation: The terms "gastrula" and "gastrulation" were coined by Ernst Haeckel , in his 1872 work "Biology of Calcareous Sponges" . Gastrula (literally, "little belly") is
1280-761: A move that earned him much scorn from his contemporaries. In the 150th year since his death (1955), the last remnant of the alma mater of Friedrich Schiller , the Karlsschule, was removed in favor of an expansion to the Bundesstraße 14 . Klett also dramatically expanded the public transportation of Stuttgart with the Stuttgart Stadtbahn and, in 1961, initiated a city partnership with the French city of Strasbourg as part of an attempt to mend Franco-German relations . It would be finalized in 1962 and
1440-573: A neo-Latin diminutive based on the Ancient Greek γαστήρ gastḗr ("a belly"). Lewis Wolpert , pioneering developmental biologist in the field, has been credited for noting that "It is not birth, marriage, or death, but gastrulation which is truly the most important time in your life." Gastrulation is highly variable across the animal kingdom but has underlying similarities. Gastrulation has been studied in many animals, but some models have been used for longer than others. Furthermore, it
1600-733: A new suburb on the northeastern edge of the city around the Dominican monastery Hospitalkirche. In the 1457, the first Landtag of the Estates of Württemberg was established in Stuttgart and a similar institution was established in Leonberg . After the temporary partitions of the County of Württemberg by the Treaties of Nürtingen , Münsingen , and Esslingen, Stuttgart was once again declared
1760-779: A region of 3,700 km (1,400 sq mi) containing a total of 2.76 million people as of December 2014. In addition, Stuttgart serves as a Mittelzentrum for Esslingen District cities Leinfelden-Echterdingen and Filderstadt as well as Ditzingen , Gerlingen , and Korntal-Münchingen in Ludwigsburg District. Stuttgart is also chief of the three centres Stuttgart Metropolitan Region , an area of 15,000 km (5,800 sq mi) containing 5.3 million persons. Stuttgart experiences an oceanic climate ( Köppen : Cfb ). Its summers are warm, with average highs around 25 °C (77 °F), while its winters are chilly, with daily means just above freezing. Annually,
SECTION 10
#17327766911091920-500: A role in respiratory fate of the Xenopus by activating cell lineage tracers. In amniotes (reptiles, birds and mammals), gastrulation involves the creation of the blastopore, an opening into the archenteron . Note that the blastopore is not an opening into the blastocoel , the space within the blastula , but represents a new inpocketing that pushes the existing surfaces of the blastula together. In amniotes , gastrulation occurs in
2080-411: A slower rate. The secondary mesenchyme cells, in this species, play an essential role in pulling the archenteron up to the blastocoel wall during the last phase of invagination. But can the secondary mesenchyme filopodia attach to any part of the blastocoel wall, or is there a specific target in the animal hemisphere that must be present for attachment to occur? Is there a region of the blastocoel wall that
2240-587: A small workshop in Bad Cannstatt that would become Daimler-Motoren-Gesellschaft in 1887. As a result, it is considered to be the starting point of the worldwide automotive industry and is sometimes referred to as the 'cradle of the automobile', and today Mercedes-Benz and Porsche both have their headquarters in Stuttgart, as well as automotive parts giants Bosch and Mahle . The year prior, Robert Bosch opened his first "Workshop for Precision Mechanics and Electrical Engineering" in Stuttgart. In 1907,
2400-647: A trip to West Germany to offer a spot for a West German astronaut in a Soviet space mission, visited Stuttgart 14 June 1989 and was the honored guest of a sumptuous reception held at the New Palace . Since the monumental happenings of the 1980s, Stuttgart has continued being an important centre of not just Europe, but also the world. In 1993, the World Horticultural Exposition , for which two new bridges were built, and World Athletics Championships of that year took place in Stuttgart in
2560-405: A tube and shook it to separate the cells. He reported that, contrary to Roux's findings, he ended up with completely formed but smaller embryos. The reason for this discrepancy has been widely attributed to Driesch separating the two blastomeres completely rather than just killing one as Roux had done. Others, including Thomas Hunt Morgan and Oscar Hertwig , attempted to separate the two cells, for
2720-439: Is already committed to becoming the ventral side of the larva? Studies by Hardin and McClay (1990) show that there is a specific target site for the filopodia that differs from other regions of the animal hemisphere. The filopodia extend, touch the blastocoel wall at random sites, and then retract. However, when the filopodia contact a particular region of the wall, they remain attached there, flatten out against this region, and pull
2880-709: Is an important financial center ; the Stuttgart Stock Exchange is the second largest in Germany (after Frankfurt ), and the Landesbank Baden-Württemberg (LBBW) is Germany's largest Landesbank . Stuttgart is also a major transport junction; it is among the most congested conurbations of Europe, and its airport is the sixth-busiest in Germany (2019). Stuttgart is a city with a high number of immigrants; according to Dorling Kindersley 's Eyewitness Travel Guide to Germany , "In
3040-403: Is dependent on the nutrition it received from the jettisoned larva. The echinoderm pattern of gastrulation provides the evolutionary prototype for deuterostome development. In deuterostomes (echinoderms, tunicates, cephalochordates, and vertebrates), the first opening becomes the anus while the second opening becomes the mouth.Moreover,in sea urchins we see the phenomena of convergent extension and
3200-431: Is easier to study development in animals that develop outside the mother. Model organisms whose gastrulation is understood in the greatest detail include the mollusc , sea urchin , frog , and chicken . A human model system is the gastruloid . The distinction between protostomes and deuterostomes is based on the direction in which the mouth (stoma) develops in relation to the blastopore . Protostome derives from
3360-415: Is formed when the cells of the embryo form the "egg cylinder", which consists of the extraembryonic tissues, which give rise to structures like the placenta , at the proximal end and the epiblast at the distal end. Many signaling pathways contribute to this reorganization, including BMP , FGF , nodal , and Wnt . Visceral endoderm surrounds the epiblast . The distal visceral endoderm (DVE) migrates to
SECTION 20
#17327766911093520-490: Is known as the " cradle of the automobile ". As such, it is home to famous automobile museums like the Mercedes-Benz Museum and Porsche Museum , as well as numerous auto-enthusiast magazines, which contributes to Stuttgart's status as Germany's " Autohauptstadt " ("car capital city"/"capital of cars"). The city's tourism slogan is "Stuttgart offers more". Under current plans to improve transport links to
3680-463: Is needed for the up regulation of SNAI1 , which down regulates E-cadherin , causing a loss of cell adhesion. Following the EMT, the cells ingress through the primitive streak and spread out to form a new layer of cells or join existing layers. FGF8 is implicated in the process of this dispersal from the primitive streak . There are certain signals that play a role in determination and formation of
3840-477: Is reliant upon nodal signaling in the Koller's sickle within the cells contributing to the primitive streak and BMP4 signaling from the extraembryonic tissue. Furthermore, Cer1 and Lefty1 restrict the primitive streak to the appropriate location by antagonizing nodal signaling. The region defined as the primitive streak continues to grow towards the distal tip. During the early stages of development,
4000-571: Is still active today. Klett's Stuttgart saw two major media events: the same year the partnership with Strasbourg was finalized, then French president Charles de Gaulle visited the city and Ludwigsburg Palace in the ending moments of his state visit to Germany, and Queen Elizabeth II of the United Kingdom visited the city 24 May 1965. On 25 April 1952, the other two parts of the former German states of Baden and Württemberg , South Baden and Württemberg-Hohenzollern merged and formed
4160-845: Is the capital and largest city of the German state of Baden-Württemberg . It is located on the Neckar river in a fertile valley known as the Stuttgarter Kessel (Stuttgart Cauldron) and lies an hour from the Swabian Jura and the Black Forest . Stuttgart has a population of 632,865 as of 2022, making it the sixth largest city in Germany , while over 2.8 million people live in the city's administrative region and nearly 5.5 million people in its metropolitan area , making it
4320-730: The Augsburg Interim by the Duke in 1548. Duke Ulrich himself died two years later, and was succeeded by his son, Christoph . He had grown up in a Württemberg in turmoil, and wished to rebuild its image. To this end, he once again began a construction boom all over the Duchy under the direction of Court Architect Aberlin Tretsch; knowing full well that the time of the Reisekönigtum was over, Christoph and Tretsch rebuilt and remodeled
4480-783: The Birkenkopf (511 m (1,677 ft)) on the edge of the Stuttgart basin , the Württemberg (411 m (1,348 ft)) rising above the Neckar valley, and the Grüner Heiner (395 m (1,296 ft)) at the northeast end of the city. Stuttgart is one of 14 regional centers in Baden-Württemberg and is naturally the primary centre of the Stuttgart Region , making it the administrative centre for
4640-652: The FIFA World Cup as it had in 1974. Stuttgart still experienced some growing pains even long after its recovery from the Second World War. In 2010, the inner city become the focal point of the protests against the controversial Stuttgart 21 . Since shortly after the end of World War II, there has been a US military presence in Stuttgart. At the height of the Cold War over 45,000 Americans were stationed across over 40 installations in and around
4800-462: The Free imperial city of Esslingen by ordering his Vogt, Konrad IV von Weinberg, to declare war on Eberhard I. Eberhard I, defeated on the battlefield, lost Stuttgart and his castle (razed in 1311) to Esslingen and the city was thus managed by the city state from 1312 to 1315. Total destruction of the county was prevented by Henry VII's death on 24 August 1313 and the elections of Louis IV as King of
4960-792: The International Socialist Congress was held in Stuttgart was attended by about 60,000 people. In 1912, VfB Stuttgart was founded. Two years later, the current iteration of the Stuttgart Hauptbahnhof was completed according to plan by Paul Bonatz from 1914 to 1927. During World War I , the city was a target of air raids. In 1915, 29 bombs struck the city and the nearby Rotebühlkaserne, killing four soldiers and injuring another 43, and likewise killing four civilians. The next major air raid on Stuttgart occurred 15 September 1918, when structural damage caused house collapses that killed eleven people. At
Hans Spemann - Misplaced Pages Continue
5120-787: The Kaiser Wilhelm Institute of Biology at Dahlem, Berlin . Here he undertook the experiments that would make him famous. Drawing upon the recent work of Warren H. Lewis and Ethel Browne Harvey , he turned his skills to the gastrula , grafting a "field" of cells (the Primitive knot ) from one embryo onto another. The experiments, performed by Hilde Proescholdt (later Mangold) , a Ph.D. candidate in Spemann's laboratory in Freiburg , took place over several years and were published in full only in 1924. They described an area in
5280-601: The Red Army Faction , during their trial at the Oberlandesgericht Stuttgart in 1975. Several attempts were made by the organization to free the terrorists during the " German Autumn " of 1977 that culminated in such events as the kidnap and murder of Hanns-Martin Schleyer and the hijacking of Lufthansa Flight 181 . When it became clear, after many attempts to free the inmates including
5440-643: The Shoah . An early concept of the Marshall Plan aimed at supporting reconstruction and economic/political recovery across Europe was presented during a speech 6 September 1946 given by US Secretary of State James F. Byrnes at the Stuttgart Opera House . His speech led to the unification of the British and American occupation zones, resulting in the 'bi-zone' (later the 'tri-zone' when
5600-732: The Thirty Years' War and devastating air raids by the Allies on the city and its automobile production during World War II . However, by 1952, the city had bounced back and became the major cultural, economic, industrial, financial, tourism and publishing centre it is today. Stuttgart is known for its strong high-tech industry, especially in the automotive sector . It has the highest general standard of prosperity of any German city. In addition to many medium-sized companies , several major corporations are headquartered in Stuttgart, including Porsche , Bosch , and Mercedes-Benz Group . Stuttgart
5760-831: The University of Music and Performing Arts later, in 1857. Stuttgart had a role to play during the revolution of 1848/1849 as well. When internal divisions of the Frankfurt Parliament began the demise of that congress, the majority of the Frankfurt Congress voted to move to Stuttgart to flee the reach of the Prussian and Austrian armies in Frankfurt and Mainz . Even though the Congress may have had contacts with revolutionaries in Baden and Württemberg ,
5920-745: The Volkswagen Beetle were manufactured in Stuttgart, according to designs by Ferdinand Porsche , by a design team including Erwin Komenda and Karl Rabe . The Hotel Silber (English: Silver ), previously occupied by other forms of political police , was occupied by the Gestapo in 1933 to detain and torture political dissidents. The hotel was used for the transit of Nazi prisoners of conscience including Eugen Bolz , Kurt Schumacher , and Lilo Herrmann to concentration camps . The nearby court at Archive Street ( German : Archivstraße ) 12A
6080-553: The Year Without Summer and following famine, introduced the first Cannstatter Volksfest to celebrate the year's bountiful harvest. Hohenheim University was founded in 1818, and two years later the Württemberg Mausoleum as completed on the hill where Wirtemberg Castle once stood. From the outset of the 19th century, Stuttgart's development was once again impeded by its location (population of
6240-417: The anterior portion of the embryo, forming the anterior visceral endoderm (AVE). This breaks anterior-posterior symmetry and is regulated by nodal signaling. The primitive streak is formed at the beginning of gastrulation and is found at the junction between the extraembryonic tissue and the epiblast on the posterior side of the embryo and the site of ingression . Formation of the primitive streak
6400-417: The blastocyst , is reorganized into a two-layered or three-layered embryo known as the gastrula . Before gastrulation, the embryo is a continuous epithelial sheet of cells; by the end of gastrulation, the embryo has begun differentiation to establish distinct cell lineages , set up the basic axes of the body (e.g. dorsal–ventral , anterior–posterior ), and internalized one or more cell types including
6560-481: The fourth largest metropolitan area in Germany . The city and metropolitan area are consistently ranked among the top 4 European metropolitan areas by GDP ; Mercer listed Stuttgart as 21st on its 2015 list of cities by quality of living ; innovation agency 2thinknow ranked the city 24th globally out of 442 cities in its Innovation Cities Index; and the Globalization and World Cities Research Network ranked
Hans Spemann - Misplaced Pages Continue
6720-588: The nodal signaling . Nodal signaling uses ligands that are part of TGFβ family. These ligands will signal transmembrane serine/threonine kinase receptors, and this will then phosphorylate Smad2 and Smad3 . This protein will then attach itself to Smad4 and relocate to the nucleus where the mesendoderm genes will begin to be transcribed. The Wnt pathway along with β-catenin plays a key role in nodal signaling and endoderm formation. Fibroblast growth factors (FGF), canonical Wnt pathway, bone morphogenetic protein (BMP), and retinoic acid (RA) are all important in
6880-602: The 100,000 inhabitant mark. This number doubled, due to the incorporation of local towns, to approximately 185,000 in 1901 and then 200,000 in 1904. In 1871, Württemberg joined the German Empire created by Otto von Bismarck , Prime Minister of Prussia , during the Unification of Germany , as an autonomous kingdom. Stuttgart is purported to be the location of the automobile's invention by Karl Benz and then industrialized by Gottlieb Daimler and Wilhelm Maybach in
7040-570: The 1923 death of Albert Leo Schlageter in Freiburg attracted particular attention. Hans Spemann suspended classes on June 6 and, with the deans in full regalia, went in a joint funeral procession with representatives of the student body and corporations to the train station, where they met with delegations of officers from Schlageter's former regiment and the German Officers' Association and students from Schlageter's former high school. Upon
7200-502: The 2-8 cells at the vegetal pole become bottle-shaped, constricting their apical ends. This change causes the cells to pucker inward. Destroying these cells with lasers retards gastrulation. In addition, the hyaline layer at the vegetal plate buckles inward due to changes in its composition .The hyaline layer is actually made up of two layers, an outer lamina made primarily of hyalin protein and an inner lamina composed of fibropellin proteins. Fibropellins are stored in secretory granules within
7360-583: The Cold War developed US Army VII Corps was re-formed in July 1950 and assigned to Hellenen Kaserne (renamed Kelley Barracks in 1951) where the headquarters was to remain throughout the Cold War. In 1990 VII Corps was deployed directly from Germany to Saudi Arabia for Operations Desert Shield and Desert Storm to include many of the VII Corps troops stationed in and around Stuttgart. After returning from
7520-634: The Congress, not popular with the content citizens of Stuttgart, were driven out by the King's army. Stuttgart's literary tradition also bore yet more fruits, being the home of such writers of national importance as Wilhelm Hauff , Ludwig Uhland , Gustav Schwab , and Eduard Mörike . From 1841 to 1846, the Jubiläumssäule was erected on the Schlossplatz before the New Palace according to
7680-534: The French forces coordinated with the US Seventh Army and VI Corps heavy artillery, who began a barrage of the city. The French 5th Armored Division then captured Stuttgart on 21 April 1945, encountering little resistance. The city fared poorly under their direction; French troops forcefully quartered their troops in what housing remained in the city, rapes were frequent (there were at least 1,389 recorded incidents of rape of civilians by French soldiers), and
7840-575: The French reluctantly agreed to cede their occupied territory to the new state). In 1948, the city applied to become the capital of the soon to-be Federal Republic of Germany , and was a serious contender against Frankfurt , Kassel , and Bonn . All these cities were examined by the Parlamentarischer Rat , but ultimately Bonn won the bid when the Republic was founded on 23 May 1949. The city's bid for capital failed primarily because of
8000-525: The Germans and Frederick III as anti-king. Eberhard seized the opportunity granted to him by the political chaos, and recaptured his hometown and birthplace in 1316, and made much territorial gain. With peace restored at last, Eberhard began repairs and expansion to Stuttgart beginning with the reconstruction of Wirtemberg Castle , ancestral home to the House of Württemberg, in 1317 and then began expansion of
8160-466: The Greek word protostoma meaning "first mouth" (πρῶτος + στόμα) whereas Deuterostome's etymology is "second mouth" from the words second and mouth (δεύτερος + στόμα). The major distinctions between deuterostomes and protostomes are found in embryonic development : Sea urchins have been important model organisms in developmental biology since the 19th century. Their gastrulation is often considered
SECTION 50
#17327766911098320-674: The Karlsschule to prevent the spreading of revolutionary ideas. Stuttgart was proclaimed capital once more when Württemberg became an electorate in 1803, and was yet again named as capital when the Kingdom of Württemberg was formed in 1805 by the Peace of Pressburg . King Frederick I 's Württemberg was given high status in the Confederation of the Rhine among the College of Kings, and
8480-452: The Killesburg park and Gottlieb-Daimler-Stadion respectively, bringing millions of new visitors to the city. At the 1993 WCA, British athlete Sally Gunnell and the United States Relay team both set world records . In 2003, Stuttgart applied for the 2012 Summer Olympics but failed in their bid when the German Committee for the Olympics decided on Leipzig to host the Olympics in Germany. Three years later, in 2006, Stuttgart once again hosted
8640-415: The League's conquest of Württemberg. Württemberg was then sold by the League to Emperor Charles V , who then granted it to his brother, Ferdinand I , thus beginning the 12 year ownership of the county by the Habsburgs . When the peasants Ulrich had crushed before rose once again in the German Peasants' War , Stuttgart was occupied by the peasant armies for a few days in the Spring of 1525. Ulrich, with
8800-440: The Middle East, the bulk of VII Corps units were reassigned to the United States or deactivated. The VII Corps Headquarters returned to Germany for a short period to close out operations and was deactivated later in the United States. The withdrawal of VII Corps caused a large reduction in the US military presence in the city and region and led to the closure of the majority of US installations in and around Stuttgart which resulted in
8960-400: The Old Castle into a Renaissance palace, and from 1542 to 1544, what is today the Schillerplatz was built as a town square. Duke Christoph also responded to the increasing made for drinking water by embarking upon a massive hydraulic engineering project in the form of a 2,810 ft (860 m) tunnel to Pffaf Lake, the Glems , and the Nesenbach from 1566 to 1575. In 1575, Georg Beer
9120-462: The Romans , entered the city in 1634 and, two years later in 1636, once again attempted to re-Catholicize Württemberg. The next year, the Bubonic plague struck and devastated the population. The Duke returned in 1638 to a realm somewhat partitioned to Catholic factions in the region, and entirely ravaged by the war. In the Duchy itself, battle, famine , plague and war reduced the Duchy's population of 350,000 in 1618 to 120,000 in 1648 – about 57% of
9280-460: The Stuttgart we know today in c. 1220 . In 1251, the city passed to the Ulrich I von Württemberg as part of Mechthild von Baden's dowry . His son, Eberhard I "the Illustrious", would be the first to begin the many major expansions of Stuttgart under the House of Württemberg. Eberhard desired to expand the realm his father had built through military action with the aid of the anti-king Henry Raspe IV , Landgrave of Thuringia , but
9440-409: The antero-posterior body axis, becoming the first symmetry-breaking event in the embryo , and marks the beginning of gastrulation. This process involves the ingression of mesoderm and endoderm progenitors and their migration to their ultimate position, where they will differentiate into the three germ layers. The localization of the cell adhesion and signaling molecule beta-catenin is critical to
9600-411: The archenteron and found the target as freely migrating cells. There appears, then, to be a target region on what is to become the ventral side of the larva that is recognized by the secondary mesenchyme cells, and which positions the archenteron in the region where the mouth will form. As the top of the archenteron meets the blastocoel wall in the target region, the secondary mesenchyme cells disperse into
9760-415: The archenteron extends dramatically, sometimes tripling its length. In this process of extension, the wide, short gut rudiment is transformed into a long ,thin tube. To accomplish this extension, the cells of the archenteron rearrange themselves by migrating over one another and by flattening themselves (Ettensohn 1985; Hardin and Cheng 1986). This phenomenon, where cells intercalate to narrow the tissue and at
SECTION 60
#17327766911099920-470: The archenteron toward it. When Hardin and McClay poked in the other side of the blastocoel wall so that contacts were made most readily with that region, the filopodia continued to extend and retract after touching it. Only when the filopodia found their target tissue did they cease these movements. If the gastrula was constricted so that the filopodia never reached the target area, the secondary mesenchyme cells continued to explore until they eventually moved off
10080-432: The archenteron. The frog genus Xenopus has been used as a model organism for the study of gastrulation. The sperm contributes one of the two mitotic asters needed to complete first cleavage. The sperm can enter anywhere in the animal half of the egg but its exact point of entry will break the egg's radial symmetry by organizing the cytoskeleton . Prior to first cleavage, the egg's cortex rotates relative to
10240-512: The archetype for invertebrate deuterostomes. Experiments along with computer simulations have been used to gain knowledge about gastrulation in the sea urchin. Recent simulations found that planar cell polarity is sufficient to drive sea urchin gastrulation. Shortly after the blastula hatches from its fertilization envelope, a group cells derived from the micromeres undergoes an epithelial-to-mesenchymal transformation. These cells change their cytoskeleton, become bottle-shaped, lose their adhesions to
10400-412: The area. Since the seventh millennium BC, the Stuttgart area has been an important agricultural area and has been host to a number of cultures seeking to utilize the rich soil of the Neckar valley . The Roman Empire conquered the area in AD 83 and built a massive castrum near Bad Cannstatt , making it the most important regional centre for several centuries. Stuttgart's roots were truly laid in
10560-522: The arrangement of the germ layers in the human embryo. Finally, using 3D embryoid body - and organoid -based techniques, small aggregates of mouse ESCs ( Embryonic Organoids, or Gastruloids ) are able to show a number of processes of early mammalian embryo development such as symmetry-breaking, polarisation of gene expression, gastrulation-like movements, axial elongation and the generation of all three embryonic axes (anteroposterior, dorsoventral and left-right axes). In vitro fertilization occurs in
10720-504: The attack on the city was to be conducted by the US Seventh Army's 100th Infantry Division , French leader Charles de Gaulle found this to be unacceptable, as he felt the capture of the region by Free French forces would increase French influence in post-war decisions. Independently, he directed General de Lattre to order the French 5th Armored Division , 2nd Moroccan Infantry Division and 3rd Algerian Infantry Division to begin their drive to Stuttgart on 18 April 1945. Two days later,
10880-426: The biologist and psychologist Gustav Wolff who had begun experiments on the embryological developments of newts and shown that, if the lens of a developing newt's eye is removed, it regenerates. In 1892 Spemann married Klara Binder with whom he had a daughter (Margaret) and three sons (Fritz, Rudolph, Ulrich). In 1893–1894 he moved to the University of Munich for clinical training but decided, rather than becoming
11040-404: The blastocoel wall (Dan and Okazaki 1956; Schroeder 1981). The filopodia attach to the wall at the junctions between the blastomeres and then shorten, pulling up the archenteron. The secondary mesenchyme cells with a laser, with the result that the archenteron could elongate to only about two-thirds of the normal length. If a few secondary mesenchyme cells were left, elongation continued, although at
11200-400: The blastocoel, where they proliferate to form the mesodermal organs. Where the archenteron contacts the wall, a mouth is eventually formed. The mouth fuses with the archenteron to create a continuous digestive tube. Thus, as is characteristic of deuterostomes, the blastopore marks the position of the anus. As the pluteus larva elongates, the coelomic cavities form from secondary mesenchyme. Under
11360-434: The blastopore is the mechanical driver of gastrulation. The first sign of invagination seen in the frog is the dorsal lip. In the frog, Xenopus, one of the signals is retinoic acid (RA). RA signaling in this organism can affect the formation of the endoderm and depending on the timing of the signaling, it can determine the fate whether its pancreatic, intestinal, or respiratory. Other signals such as Wnt and BMP also play
11520-628: The capital of the county in 1483. In 1488, Stuttgart officially became the de facto residence of the Count himself as opposed to the location of his home, the Old Castle. Eberhard I , then Count Eberhard V, became the first Duke of Württemberg in 1495, and made Stuttgart the seat of the Duchy of Württemberg in addition to the County thereof. All this would be lost to the Württembergs during
11680-617: The catastrophic defeat of the Protestant Heilbronn League by the Habsburgs at Nörlingen in 1634, Duke Eberhard III and his court fled in exile to Strasbourg , abandoning the Duchy to looting by pro- Habsburg forces. The Habsburgs once again had full reign of the city for another four years, and in that time Stuttgart had to carry the burden of billeting the pro-Habsburg armies in Swabia . Ferdinand III , King of
11840-436: The cells lateral to them, and then break away from the apical layer to enter the blastocoel. These micromere-derived cells are called the primary mesenchyme. Since they will form the larval skeleton, they are sometimes called the skeletogenic mesenchyme. These mesenchyme cells begin extending and contracting long, thin (250 nm in diameter and 25 μm long) processes called filopodia. At first the cells appear to move randomly along
12000-504: The central T sound. Originally, the most important location in the Neckar river valley was the hilly rim of the Stuttgart basin at what is today Bad Cannstatt . Thus, the first settlement of Stuttgart was a massive Roman Castra stativa ( Cannstatt Castrum ) built c. 90 AD to protect the Villas and vineyards blanketing the landscape and the road from Mogontiacum (Mainz) to Augusta Vindelicorum (Augsburg). Cannstatt
12160-565: The centre of Swabia and the local dialect spoken by the native Swabians , has its etymological roots in the Old High German word Stuotgarten , or " stud farm ", because the city was founded in 950 AD by Duke Liudolf of Swabia to breed warhorses. In the local dialects of Alemannic German it can be " Schtuegert ", and in Swabian German " Stuagart "; with similar variant spellings, usually dropping
12320-404: The city as a Beta -status global city in their 2020 survey. Stuttgart was one of the host cities for the official tournaments of the 1974 and 2006 FIFA World Cups . Stuttgart is unusual in the scheme of German cities. It is spread across a variety of hills (some of them covered in vineyards ), valleys (especially around the Neckar river and the Stuttgart basin ) and parks . The city
12480-652: The city at the time was around 50,000), but the city began to experience the beginning of economic revival with the opening of the Main Station in 1846. Prior to then, the signs of rebirth in Stuttgart were evidenced by the construction of such buildings of Rosenstein Castle in 1822–1830, the Wilhelmspalais 1834–1840, and the foundations of the Staatsgalerie in 1843, University of Stuttgart in 1829,
12640-464: The city of Stuttgart, every third inhabitant is a foreigner." 40% of Stuttgart's residents, and 64% of the population below the age of five, are of immigrant background. In the rest of Germany, 28.7% of people are of immigrant background, with a relatively higher percentage living in cities and former western Germany (such as Stuttgart). Stuttgart, often nicknamed the " Schwabenmetropole " (English: Swabian metropolis ) in reference to its location in
12800-514: The city receives average 718.7 mm (28.30 in) of rain. On average, Stuttgart enjoys 1,807 hours of sunshine per year and an average annual temperature of 9 °C (48 °F). Typically during summer months, the nearby hills, Swabian Alb mountains, the Black Forest , Schurwald , and the Swabian-Franconian Forest act as shields from harsh weather, nevertheless the city can be subject to thunderstorms, whereas in
12960-636: The city were suicidal, substantial damage to the city's industrial capacity still occurred, such as the 25 August bombing of the Daimler AG plant in 1940 that killed five people. With the war increasingly turning against the Third Reich, more and more troops were pulled from the defence of the city in 1943 to fight on the Eastern Front . In 1944, the city centre was entirely in ruins due to Allied bombing raids that could now more easily attack
13120-473: The city's defenses. The early 1320s were important years for Stuttgart: Eberhard I moved the seat of the county to the city to a new and expanded castle , the collegiate church in Beutelsbach , where previous members of the Württemberg dynasty had been buried prior to its destruction in 1311, moved to its current location in Stuttgart in 1320, and the town's Stiftkirche was expanded into an abbey, and
13280-472: The city's royal past. These include: Other landmarks in and around Stuttgart include ( see also museums below ): At the center of Stuttgart lies a series of gardens which are popular with families and cyclists. Because of its shape on a map, the locals refer to it as the Green U . The Green U starts with the old Schlossgarten, castle gardens first mentioned in records in 1350. The modern park stretches down to
13440-598: The city's surviving populace were poorly rationed. The circumstances of what later became known as "The Stuttgart Crisis" provoked political repercussions that reached even the White House . President Harry S. Truman was unable to get De Gaulle to withdraw troops from Stuttgart until after the final boundaries of the zones of occupation were established. The French army remained in the city until they finally relented to American demands on 8 July 1945 and withdrew. Stuttgart then became capital of Württemberg-Baden , one of
13600-564: The city. Economic migrants , called " Gastarbeiter ", from Italy, and later Greece and Turkey but primarily from Yugoslavia , came flocking to Stuttgart because of the economic wonder called the " Wirtschaftswunder " unfolding in West Germany . These factors saw the city reach its (then) peak population of 640,000 in 1962. In May 1965 Queen Elizabeth II made a state visit to Stuttgart and nearby Marbach and Schwäbisch Hall . Her great-grandfather Duke Francis (1837–1900) had been
13760-769: The city. Today about 10,000 Americans are stationed on 5 installations (Patch Barracks, Panzer Kaserne, Kelley Barracks, Robinson Barracks, and Stuttgart Army Airfield) representing all branches of service within the Department of Defense , unlike the mostly Army presence of the Occupation and Cold War. In March 1946 the US Army established a unit of the US Constabulary and a headquarters at Kurmärker Kaserne (later renamed Patch Barracks ) in Stuttgart. These units of soldiers retrained in patrol and policing provided
13920-494: The city. The heaviest raid took place on 12 September 1944, when the Royal Air Force , dropping over 184,000 bombs – including 75 blockbusters – levelled Stuttgart's city centre, killing 957 people in the resulting firestorm . In totality, Stuttgart was subjected to 53 bombing raids, resulting in the destruction of 57.7% of all buildings in the city, the deaths of 4,477 inhabitants, the disappearance of 85 citizens, and
14080-618: The control of the Martinskirche by the Bishopric of Constance was broken by Papal order in 1321. A year after the city became the principal seat of the Counts of Württemberg in 1320, the city was granted status as a city and given civic rights. At the end of the 14th century, new suburbs sprang up around Leonhard Church and near the city's fortifications as well. Towards the end of the 15th century, Count Ulrich V began construction of
14240-430: The cost of associated in vivo work (thereby reducing, replacing and refining the use of animals in experiments; the 3Rs ), being able to accurately apply agonists/antagonists in spatially and temporally specific manner which may be technically difficult to perform during Gastrulation. However, it is important to relate the observations in culture to the processes occurring in the embryo for context. To illustrate this,
14400-562: The development of the middle ear in the frog. Spemann advocated a holistic approach to biology. During the winter of 1896, while quarantined in a sanitarium recovering from tuberculosis , Spemann read August Weismann 's book The Germ Plasm: A Theory of Heredity . He wrote in his autobiography: "I found here a theory of heredity and development elaborated with uncommon perspicacity to its ultimate consequences.....This stimulated experimental work of my own". Results in embryology had been contradictory: in 1888 Wilhelm Roux , who had introduced
14560-499: The embryo, the portions of which, upon transplantation into a second embryo, organized or "induced" secondary embryonic primordia regardless of location. Spemann called these areas " organiser centres " or "organisers". Later he showed that different parts of the organiser centre produce different parts of the embryo. Despite his modern reputation, Spemann continued to entertain neo- vitalist "field" analyses similar to those of Hans Driesch , Gurwitsch and Harold Saxton Burr . However,
14720-459: The end of the Cold War as they are host to United States Department of Defense Unified Commands and supporting activities. The core area of Stuttgart lies in a fertile bowl-shaped valley about 900 ft (270 m) above sea level , an hour from the Black Forest and Swabian Jura on the banks of the Neckar river at 48°47′N 9°11′E / 48.783°N 9.183°E / 48.783; 9.183 115 mi (185 km) to
14880-661: The end of the First World War, November revolutionaries stormed the Wilhelmpalais on 30 November 1918 to force King Wilhelm II to abdicate, but failed halfway. Under pressure from the revolutionaries, Wilhelm II refused the crown, but also refused to abdicate the throne. When he did eventually abdicate, the Free State of Württemberg was established as a part of the Weimar Republic , and Stuttgart
15040-616: The entire male Jewish population of Stuttgart, to the police-run prison camp at Welzheim or directly to Dachau . Other Jews from around Württemberg were brought to Stuttgart and housed in the ghetto on the former Trade Fair grounds in Killesberg . As the Memorial at Stuttgart North records, between 1941 (the first train arrived 1 December 1941, and took around 1,000 men to Riga ) and 1945, more than 2,000 Jews from all over Württemberg were deported to Theresienstadt , Auschwitz , and
15200-583: The existence of a settlement here (despite the terrain being more suited for that original stud farm) during the High Middle Ages is provided by a gift registry from Hirsau Abbey dated to around 1160 that mentions a "Hugo de Stuokarten". A settlement at this locale was again mentioned in 1229, but this time by Pope Gregory IX . In AD 1219, Stuttgart (then Stuotgarten) became a possession of Herman V , Margrave of Baden . In addition to Backnang , Pforzheim , and Besigheim , Hermann would also found
15360-437: The experimental manipulation of the embryo to discover the rules of development, performed a series of experiments in which he inserted a hot needle into one of two blastomeres to kill it. He then observed how the remaining blastomere developed, and found that it became a half embryo. In 1892 Hans Driesch performed similar experiments on sea urchin embryos, but instead of killing one of the two blastomeres he put many embryos in
15520-412: The farthest distance into the blastocoel. The next layer of endodermal cells becomes midgut, and the last circumferential row to invaginate forms the hindgut and anus. Second and third stages of archenteron invagination The invagination of the vegetal cells occurs in discrete stages. After a brief pause following the initial invagination, the second phase of archenteron formation begins. During this stage,
15680-521: The few "enduring communities" where the United States forces will continue to operate in Germany. The remaining U.S. bases around Stuttgart are organized into US Army Garrison Stuttgart and include Patch Barracks, Robinson Barracks , Panzer Kaserne and Kelley Barracks. From the end of World War II until the early 1990s these installations excepting Patch were almost exclusively Army, but have become increasingly "Purple"—as in joint service—since
15840-641: The financial burdens its high rents would place on the government. The immediate aftermath of the War would be marked by the controversial efforts of Arnulf Klett , the first Oberbürgermeister of Stuttgart, to restore the city. Klett favored the idea of a modernist Automotive city with functional divisions for residential, commercial and industrial areas according to the Athens Charter . Klett demolished both ruins and entire streets of largely undamaged buildings without rebuilding them to their original visage,
16000-470: The first cells to internalize are the primary mesenchyme cells (PMCs), which have a skeletogenic fate, which ingress during the blastula stage. Gastrulation – internalization of the prospective endoderm and non-skeletogenic mesoderm – begins shortly thereafter with invagination and other cell rearrangements the vegetal pole , which contribute approximately 30% to the final archenteron length. The gut's final length depends on cell rearrangements within
16160-822: The first moves towards cloning . He was elected an International Honorary Member of the American Academy of Arts and Sciences in 1933. He was awarded the Nobel Prize in 1935. He was elected an International Member of the American Philosophical Society in 1937. His theory of embryonic induction by organisers is described in his book Embryonic Development and Induction (1938). He died of heart failure on 12 September 1941. He never lost his love of classical literature and, throughout his life, organized evening gatherings of friends to discuss art, literature, and philosophy. The commemoration of
16320-429: The first time in centuries, Duke Eberhard Ludwig moved the seat of the Duchy out of the declining city of Stuttgart in 1718 to Ludwigsburg , founded in 1704, while the namesake Baroque palace , known as the "Versailles of Swabia", was still under construction. When Eberhard Ludwig died, his nephew Charles Alexander , ascended to the throne. Charles Alexander himself died in 1737, meaning his son Charles Eugene became
16480-415: The follow-up work of Johannes Holtfreter , Dorothy M. Needham and Joseph Needham , Conrad Waddington and others showed that organizers killed by boiling, fixing or freezing were also capable of causing induction. The conclusion was that the actual controllers were inert molecules, though little headway was made until the end of the 20th century in discovering how signalling took place. From 1919 Spemann
16640-434: The following sequence: (1) the embryo becomes asymmetric ; (2) the primitive streak forms; (3) cells from the epiblast at the primitive streak undergo an epithelial to mesenchymal transition and ingress at the primitive streak to form the germ layers . In preparation for gastrulation, the embryo must become asymmetric along both the proximal-distal axis and the anteroposterior axis . The proximal-distal axis
16800-461: The formation and development of the endoderm. FGF are important in producing the homeobox gene which regulates early anatomical development. BMP signaling plays a role in the liver and promotes hepatic fate. RA signaling also induce homeobox genes such as Hoxb1 and Hoxa5. In mice, if there is a lack in RA signaling the mouse will not develop lungs. RA signaling also has multiple uses in organ formation of
16960-433: The gastrula stage. Gastrulation takes place after cleavage and the formation of the blastula, or blastocyst. Gastrulation is followed by organogenesis , when individual organs develop within the newly formed germ layers. Each layer gives rise to specific tissues and organs in the developing embryo. Following gastrulation, cells in the body are either organized into sheets of connected cells (as in epithelia ), or as
17120-586: The ghettos at Riga and Izbica . Of them, only 180 held in Internment survived the Shoah . Stuttgart, like many of Germany's major cities, was ravaged throughout the war by Allied air raids . For the first four years of the war, successful air raids on the city were rare because of the capable defence of the city by Wehrmacht ground forces, the Luftwaffe , and artificial fog . Despite opinions among some Royal Air Force members that day-time air raids on
17280-448: The guided differentiation of mouse ESCs has resulted in generating primitive streak –like cells that display many of the characteristics of epiblast cells that traverse through the primitive streak (e.g. transient brachyury up regulation and the cellular changes associated with an epithelial to mesenchymal transition ), and human ESCs cultured on micro patterns, treated with BMP4 , can generate spatial differentiation pattern similar to
17440-569: The help of Philip I , Landgrave of Hesse , seized the chance to restore himself to power (albeit as an Austrian vassal) in the turmoil of the Reformation and War with the Turks and invited Erhard Schnepf to bring the Reformation to Stuttgart. He accepted, was named Court Preacher in Stuttgart, and worked in concert with Ambrosius Blarer until his dismissal following his resistance to
17600-440: The influence of Nodal protein, as described on page 221, the right coelomic sac remains rudimentary. However, the left coelomic sac undergoes extensive development to form many of the structures of the adult sea urchin. The left sac splits into three smaller sacs. An invagination from the ectoderm fuses with the middle sac to form the imaginal rudiment. This rudiment develops a fivefold symmetry, and skeletogenic mesenchyme cells enter
17760-453: The injury of 8,908 more people. The Allies lost 300 aircraft and seven to ten enlisted men. To commemorate the city citizens who died during the war, the rubble was assembled and used to create the Birkenkopf . Today Stuttgart consists to over 40% of buildings from before World War II, besides all destruction. The Allied ground advance into Germany reached Stuttgart in April 1945. Although
17920-423: The inner blastocoel surface, actively making and breaking filopodial connections to the wall of the blastocoel. Eventually, however, they become localized within the prospective ventrolateral region of the blastocoel. Here they fuse into syncytial cables, which will form the axis of the calcium carbonate spicules of the larval skeletal rods First stage of archenteron invagination As the primary mesenchyme cells leave
18080-403: The inner lamina, but not the outer lamina, which causes the vegetal region of the hyaline layer to buckle. Slightly later a second force, arising from the movements of epithelial cells adjacent to the vegetal plate, may facilitate invagination by drawing the buckled layer inward (Burke et al. 1991).At the stage when the skeletogenic mesenchyme cells begin ingressing into the blastocoel, the fates of
18240-420: The internal cytoplasm by the coordinated action of microtubules , in a process known as cortical rotation. This displacement brings maternally loaded determinants of cell fate from the equatorial cytoplasm and vegetal cortex into contact, and together these determinants set up the organizer . Thus, the area on the vegetal side opposite the sperm entry point will become the organizer. Hilde Mangold , working in
18400-464: The international infrastructure (as part of the Stuttgart 21 project), Stuttgart unveiled a new city logo and slogan in March 2008, describing itself as " Das neue Herz Europas " ("The new Heart of Europe"). For business, it describes itself as "Where business meets the future". In July 2010, the city unveiled a new logo, designed to entice more business people to stay in the city and enjoy breaks in
18560-411: The lab of Hans Spemann , demonstrated that this special "organizer" of the embryo is necessary and sufficient to induce gastrulation. Specification of endoderm depends on rearrangement of maternally deposited determinants, leading to nuclearization of Beta-catenin . Mesoderm is induced by signaling from the presumptive endoderm to cells that would otherwise become ectoderm. The dorsal lip of
18720-592: The lands of nearby secondary German states. Within Stuttgart, the royal residence was expanded under Frederick although many of Stuttgart's most important buildings, including Wilhelm Palace , Katharina Hospital, the State Gallery , the Villa Berg and the Königsbau were built under the reign of King Wilhelm I . In 1818. King Wilhelm I and Queen Catherine in an attempt to assuage the suffering caused by
18880-541: The law and order in the American zone of occupied Germany until the civilian German police forces could be re-established. In 1948 the headquarters for all Constabulary forces was moved to Stuttgart. In 2008 a memorial to the US Constabulary was installed and dedicated at Patch Barracks. The US Constabulary headquarters was disbanded in 1950 and most of the force was merged into the newly organized 7th Army . As
19040-662: The layoff of many local civilians who had been career employees of the US Army. Since 1967, Patch Barracks in Stuttgart has been home to the US EUCOM . In 2007 AFRICOM was established as a cell within EUCOM and in 2008 established as the US Unified Combatant Command responsible for most of Africa headquartered at Kelley Barracks. Due to these 2 major headquarters, Stuttgart has been identified as one of
19200-476: The matter was of great importance, particularly to the arguments between proponents of epigenesis and preformation , but satisfactory results could not be achieved. As a master of micro-surgical technique, beginning with his continuing work on the amphibian eye, Spemann's papers in the early years of the 20th century on this vexed question were to be a great contribution to the development of experimental morphogenesis , causing him to be hailed in some quarters as
19360-458: The modern German state of Baden-Württemberg , with Stuttgart as its capital. Since the 1950s, Stuttgart has been the third largest city in southern Germany behind Frankfurt and Munich . The city's population, halved by the Second World War, began sudden growth with the mass influx of German refugees expelled from their homes and communities by the Soviets from the late 1940s until 1950 to
19520-428: The municipal area. At the center of Stuttgart lies its main square, Schlossplatz . As well as being the largest square in Stuttgart, it stands at the crossover point between the city's shopping area, Schlossgarten park which runs down to the river Neckar , Stuttgart's two central castles and major museums and residential areas to the south west. Königstraße, Stuttgart's most important shopping street which runs along
19680-679: The name " Cannstatt " is not clear, but as the site is mentioned as condistat in the Annals of Metz (9th century), it is mostly derived from the Latin word condita ("foundation"), suggesting that the name of the Roman settlement might have had the prefix " Condi- ". Alternatively, Sommer (1992) suggested that the Roman site corresponds to the Civitas Aurelia G attested to in an inscription found near Öhringen . There have also been attempts at
19840-643: The name of Hans von Hutten, obliging her to flee to the court of her brother, William IV , Duke of Bavaria , who successfully had Ulrich placed under Imperial ban twice. When the Emperor died in 1519, Ulrich struck, seizing the Free Imperial City of Reutlingen , prompting the League to intervene. That same year, Ulrich was soundly defeated and he was driven into exile in France and Switzerland following
20000-583: The next nine years. Due to the Nazi Party 's practice of Gleichschaltung , Stuttgart's political importance as state capital became totally nonexistent, though it remained the cultural and economic centre of the central Neckar region. Stuttgart, one of the cities bestowed an honorary title by the Nazi regime, was given the moniker "City of the Abroad Germans " in 1936. The first prototypes of
20160-434: The northwestern edge of Schlossplatz, claims to be the longest pedestrianized street in Germany. Although the city center was heavily damaged during World War II, many historic buildings have been reconstructed and the city boasts some fine pieces of modern post-war architecture. Buildings and squares of note in the inner city include: A number of significant castles stand in Stuttgart's suburbs and beyond as reminders of
20320-443: The oocyte and are secreted from those granules after cortical granule exocytosis releases the hyalin protein. By the blastula stage, the fibropellins have formed a mesh like network over the embryo surface. At the time of invagination, the vegetal plate cells (and only those cells) secrete a chondroitin sulfate proteoglycan into the inner lamina of the hyaline layer directly beneath them. This hygroscopic (water absorbing) molecule swells
20480-746: The opening of the Stuttgart S-Bahn on 1 October 1978 with a scheduled three routes. from 17 to 19 June 1983, ten European heads of state and representatives from the European Union met in Stuttgart for a summit and there made the Solemn Declaration on European Union . In 1986, the European Athletics Championships of that year were held in the Neckarstadion . Mikhail Gorbachev , while on
20640-512: The pharyngeal arches, the foregut, and hindgut. There have been a number of attempts to understand the processes of gastrulation using in vitro techniques in parallel and complementary to studies in embryos, usually though the use of 2D and 3D cell ( Embryonic organoids ) culture techniques using embryonic stem cells (ESCs) or induced pluripotent stem cells (iPSCs). These are associated with number of clear advantages in using tissue-culture based protocols, some of which include reducing
20800-617: The plans of Johann Michael Knapp to celebrate the rule of King Wilhelm I. A decade later, the Königsbau was constructed by Knapp and court architect Christian Friedrich von Leins as a concert hall. Another milestone in Stuttgart's history was the running of the first rail line from Cannstatt to Untertürkheim on 22 October 1845. The advent of Industrialisation in Germany heralded a major growth of population for Stuttgart: In 1834, Stuttgart counted 35,200 inhabitants, rose to 50,000 in 1852, 69,084 inhabitants in 1864, and finally 91,000 residents in 1871. By 1874, Stuttgart once again exceeded
20960-563: The population of Württemberg. Recovery would be slow for the next several decades, but began nonetheless with the city's first bookstore in 1650 and high school in 1686. This progress was almost entirely undone when French soldiers under Ezéchiel du Mas appeared outside the city's walls in 1688 during the Nine Years' War , but the city was saved from another sack due to the diplomatic ability of Magdalena Sibylla , reigning over Württemberg as regent for her son, Eberhard Ludwig . For
21120-576: The premature Duke (and later King) at the age of nine. When he came of age and returned from his tutoring at the court of Frederick the Great , King of Prussia , Charles desired to move the capital back to Stuttgart. He commissioned the construction of the New Castle in 1746, Castle Solitude in 1763, Castle Hohenheim in 1785, and the Karlsschule in 1770. The rule of Charles Eugene also saw
21280-477: The primitive streak is the structure that will establish bilateral symmetry , determine the site of gastrulation and initiate germ layer formation. To form the streak, reptiles, birds and mammals arrange mesenchymal cells along the prospective midline, establishing the first embryonic axis, as well as the place where cells will ingress and migrate during the process of gastrulation and germ layer formation. The primitive streak extends through this midline and creates
21440-413: The proper formation of the organizer region that is responsible for initiating gastrulation. In order for the cells to move from the epithelium of the epiblast through the primitive streak to form a new layer, the cells must undergo an epithelial to mesenchymal transition (EMT) to lose their epithelial characteristics, such as cell–cell adhesion . FGF signaling is necessary for proper EMT. FGFR1
21600-439: The prospective gut . In triploblastic organisms, the gastrula is trilaminar (three-layered). These three germ layers are the ectoderm (outer layer), mesoderm (middle layer), and endoderm (inner layer). In diploblastic organisms, such as Cnidaria and Ctenophora , the gastrula has only ectoderm and endoderm. The two layers are also sometimes referred to as the hypoblast and epiblast . Sponges do not go through
21760-688: The reign of his son, Ulrich . Though Ulrich initially made territorial gains as a result of his decision to fight alongside the Emperor Maximilian I , he was no friend of the powerful Swabian League nor of his own subjects, who launched the Poor Conrad rebellion of 1514. Despite this and his rivalry with the Swabian League, his undoing would actually come in the form of his unhappy marriage to Sabina of Bavaria . In 1515, Ulrich killed an imperial knight and lover of Sabina's by
21920-641: The river Neckar and is divided into the upper garden (bordering the Old Castle , the Main Station , the State Theater and the State Parliament building), and the middle and lower gardens – a total of 61 hectares. The park also houses Stuttgart planetarium. Gastrula Gastrulation is the stage in the early embryonic development of most animals , during which the blastula (a single-layered hollow sphere of cells ), or in mammals
22080-417: The rudiment to synthesize the first skeletal plates of the shell. The left side of the pluteus becomes, in effect, the future oral surface of the adult sea urchin (Bury 1895; Aihara and Amemiya2001). During metamorphosis, the imaginal rudiment separates from the larva, which then degenerates. While the imaginal rudiment (now called a juvenile) is re-forming its digestive tract and settling on the ocean floor, it
22240-406: The same time move it forward, is called convergent extension (Martins et al. 1998). In all species of sea urchins observed, a third stage of archenteron elongation occurs. This final phase is initiated by the tension provided by secondary mesenchyme cells, which form at the tip of the archenteron and remain there. These cells extend filopodia through the blastocoel fluid to contact the inner surface of
22400-405: The smuggling of three weapons into the prison by their lawyer, that the terrorists could not escape and that they would receive life sentencing , the terrorists killed themselves in April 1977 in an event remembered locally as the " Todesnacht von Stammheim ", "Night of Death at Stammheim". The trauma of the early 1970s was quickly left behind, starting in 1974 with the 1974 FIFA World Cup and
22560-477: The tenth century with its founding by Liudolf , Duke of Swabia , as a stud farm for his warhorses. Initially overshadowed by nearby Bad Cannstatt, the town grew steadily and was granted a charter in 1320. The fortunes of Stuttgart turned with those of the House of Württemberg , and they made it the capital of their county , duchy , and kingdom from the 15th century to 1918. Stuttgart prospered despite setbacks in
22720-640: The third century by the Alamanni , the settlement temporarily vanished from history until the seventh century. In 700, Duke Gotfrid mentions a "Chan Stada" in a document regarding property. Archaeological evidence shows that later Merovingian era Frankish farmers continued to till the same land the Romans did. Cannstatt is mentioned in the Abbey of St. Gall 's archives as " Canstat ad Neccarum " ( German : Cannstatt-on-Neckar ) in 708. The etymology of
22880-613: The three areas of Allied occupation in Baden-Württemberg, from 1945 until 1952. The military government of the American occupation zone established a Displaced persons camp for displaced persons , mostly forced labourers from Central and Eastern European industrial firms in the area. There was, however, a camp located in Stuttgart-West that, until its closure and transportation of internees to Heidenheim an der Brenz in 1949, housed almost exclusively 1400 Jewish survivors of
23040-443: The three germ layers, such as FGF, RA, and Wnt. In mammals such as mice, RA signaling can play a role in lung formation. If there is not enough RA, there will be an error in the lung production. RA also regulates the respiratory competence in this mouse model. During gastrulation, the cells are differentiated into the ectoderm or mesendoderm , which then separates into the mesoderm and endoderm. The endoderm and mesoderm form due to
23200-585: The train's arrival, Spemann laid two wreaths, which were stowed in the semi-open baggage car decorated with flowers and emblazoned with swastikas . To the sounds of “I had a comrade”, the crowd swore Schlageter's motto "Heil, Sieg und Rache". In 1935, at the end of Spemann's acceptance speech for the Nobel Prize, he gave a Nazi salute . [REDACTED] Media related to Hans Spemann at Wikimedia Commons Stuttgart Stuttgart ( German: [ˈʃtʊtɡaʁt] ; Swabian : Schduagert [ˈʒ̊d̥ua̯ɡ̊ɛʕd̥] ; names in other languages )
23360-508: The true founder of micro-surgery. He succeeded in dividing the cells with a noose of baby hair . Spemann found that one half could indeed form a whole embryo, but observed that the plane of division was crucial. This dispatched the theory of preformation and gave some support to the concept of a morphogenetic field , a concept of which Spemann learned from Paul Alfred Weiss . Spemann was appointed Professor of Zoology and Comparative Anatomy at Rostock in 1908 and, in 1914, associate director of
23520-468: The tutoring and origins of Friedrich Schiller in Stuttgart, who studied medicine and completed The Robbers here. Stuttgart, at the end of the 18th century, remained a very provincial town of 20,000 residents, narrow alleys, and agriculture and livestock. Despite being the capital and seat of the Duchy, the general staff of the Army of Württemberg was not present in the city. In 1794, Duke Charles dissolved
23680-419: The use of Nodal gene expression for the establishment of axes. Reference :Development Biology. Eighth Edition by Scott F Gilbert Sea urchins exhibit highly stereotyped cleavage patterns and cell fates. Maternally deposited mRNAs establish the organizing center of the sea urchin embryo. Canonical Wnt and Delta-Notch signaling progressively segregate progressive endoderm and mesoderm. In sea urchins
23840-408: The vegetal plate cells have already been specified (Ruffins and Ettensohn 1996). The secondary mesenchyme is the first group of cells invaginating, and it forms the tip of the archenteron, leading the way into the blastocoel. It will form the pigment cells, the musculature around the gut, and the coelomic pouches. The endodermal cells adjacent to the micromere-derived mesenchyme become foregut, migrating
24000-461: The vegetal region of the spherical embryo, important changes are occurring in the cells that remains there .These cells thicken and flattened to form a vegetal plate, changing the shape of the blastula, these vegetal plate cells remain bound to one another and to the hyaline layer of the egg ,and they move to fill the gaps caused by ingression of the primary mesenchyme. Moreover, the vegetal plate bends inward and invaginates about one-fourth to one half
24160-423: The way into the blastocoel. Then invagination suddenly ceases. The invaginated region is called the archenteron (primitive gut), and the opening of the archenteron at the vegetal pole is called the blastopore. Invagination appears to be caused by shape changes in the vegetal plate cells and in the extracellular matrix underlying them. Kimberly and Hardin (1998) have shown that a group of vegetal plate cells surrounding
24320-500: The west and north of Munich . The city is often described as being " zwischen Wald und Reben " ("between forest and vines") because of its viticulture and surrounding forests. Stuttgart covers an area of 207.35 km (80 sq mi) and sits at elevation ranging from 207 m (679 ft) above sea level by the Neckar river to 549 m (1,801 ft) on Bernhartshöhe hill – something rather unique in large German cities. The most prominent elevated locales in Stuttgart are
24480-485: The winter periods snow may last for several days. Snow cover tends to last no longer than a few days although it had lasted several weeks at a time as recently as 2010. Though it is a rare occurrence in Stuttgart, the city sometimes receives damaging hailstorms , such as in July 2013. In order to fight this phenomenon, weather stations known as " Hagelflieger " are stationed near the city and are largely funded by Daimler AG , who maintain several parking lots and factories in
24640-495: Was Professor of Zoology at the University of Freiburg-im-Breisgau , where he continued his line of enquiry until in 1937 he was relieved of his post to be replaced by one of his first students, Otto Mangold. He was elected an International Member of the United States National Academy of Sciences in 1925. In 1928 he was the first to perform somatic cell nuclear transfer using amphibian embryos – one of
24800-462: Was a part of the Roman imperial province Germania Superior . As with many military installations, a settlement sprang up nearby and remained there even after the limes moved further east. When they did, the town was left in the capable hands of a local brickworks that produced sophisticated architectural ceramics and pottery. When the Romans were driven back past the Rhine and Danube rivers in
24960-660: Was also appointed Court Architect, and he built the Lusthaus. But it was architect Heinrich Schickhardt who would carry Tretsch's torch further; Schickhardt constructed the Stammheim Castle in the suburb of Stammheim, rebuilt the Fruchtkasten in the today's Schillerplatz, and expanded the Prinzebau. The Thirty Years' War devastated the city, and it would slowly decline for a period of time from then on. After
25120-433: Was also used as a central location for executions in Southwest Germany, as the headstone located in its atrium dedicated to the 419 lives lost there recalls. Participants of the Kristallnacht burned the Old Synagogue to the ground along with the relics contained within and also destroyed its Jewish cemetery . The next year the Nazi regime began the arrests and deportation of Stuttgart's Jewish inhabitants, beginning with
25280-456: Was declared its capital. On 26 April 1919, a new constitution was devised, and the final draft was approved and ratified on 25 September 1919 by the Constituent Assembly. In 1920, Stuttgart temporarily became the seat of the German National Government when the administration fled from Berlin from the Kapp Putsch . Also in 1920, Erwin Rommel became the company commander of the 13th Infantry Regiment based in Stuttgart and would remain as such for
25440-427: Was quashed by his father four years later. In 1089, Bruno of Calw built the precursor building to the Old Castle . Stuttgart's viticulture , first documented in the Holy Roman Empire in the year AD 1108, kept people in the area of that stud farm for some time, but the area was still largely overshadowed by nearby Cannstatt because of its role as a local crossroad for many major European trade routes. Nevertheless,
25600-491: Was thwarted by the action of Emperor Rudolph I . Further resistance by Eberhard I against the Emperor's created Vogts and Bailiwicks as well as the newly appointed Duke of Swabia Rudolf II, Duke of Austria , eventually led to armed conflict and initial successes upon Emperor Rudolph I's death in 1291 against the Emperor's men. After initially defeating his regional rivals, Henry VII , newly elected as Emperor, decided to take action against Eberhard I in 1311 during his war with
#108891