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Tail Spike
A thagomizer () is the distinctive arrangement of spike-shaped Osteoderm, osteoderms on the tails of some Stegosauria, stegosaurian dinosaurs. These spikes are believed to have been a defensive measure against predators. The arrangement of spikes originally had no distinct name. Cartoonist Gary Larson invented the name "thagomizer" in 1982 as a joke in his comic strip ''The Far Side'', and it was gradually adopted as an informal term sometimes used within scientific circles, research, and education. Etymology The term ''thagomizer'' was coined by Gary Larson in jest. In a 1982 ''The Far Side'' comic, a group of caveman, cavemen are taught by a caveman lecturer that the spikes on a stegosaur's tail were named "after the late Thag Simmons". The term was picked up initially by Kenneth Carpenter, then a paleontologist at the Denver Museum of Nature and Science, who used the term when describing a fossil at the Society of Vertebrate Paleontology Annual Meeting in 1993. ''Thagomizer' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kentrosaurus
''Kentrosaurus'' ( ; ) is a genus of stegosaurid dinosaur from the Late Jurassic in Lindi Region of Tanzania. The type species is ''K. aethiopicus'', named and described by German people, German Palaeontology, palaeontologist Edwin Hennig in 1915. Often thought to be a "Primitive (phylogenetics), primitive" member of the Stegosauria, several recent cladistic analyses find it as more derived than many other stegosaurs, and a close relative of ''Stegosaurus'' from the North American Morrison Formation within the Stegosauridae. Fossils of ''K. aethiopicus'' have been found only in the Tendaguru Formation, dated to the late Kimmeridgian and early Tithonian ages, about 152 annum, million years ago. Hundreds of bones were unearthed by German expeditions to German East Africa between 1909 and 1912. Although no complete skeletons are known, the remains provided a nearly complete picture of the build of the animal. In the Tendaguru Formation, it coexisted with a variety of dinosaurs such ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tail Club
In zoology, a tail club is a bony mass at the end of the tail of some dinosaurs and of some mammals, most notably the Ankylosauridae, ankylosaurids and the glyptodonts, as well as meiolaniid turtles. It is thought that this was a form of defensive Armour (zoology), armour or weapon that was used to defend against predators, much in the same way as a thagomizer, possessed by stegosaurids, though at least in glyptodonts it is hypothesized it was used in Display (zoology), fighting for mating rights. Among dinosaurs, the club was present mainly in ankylosaurids, although Sauropoda, sauropods like ''Shunosaurus'' and ''Kotasaurus'' also possessed a tail club. Victoria Arbour has established that ankylosaurid tails could generate enough force to break bone during impacts. In a separate study, Arbour suggested tail clubs as well as large armoured herbivores as a whole evolve when animals are too large to hide and too small to avoid predation by size alone. Morphology In ankylosaurid di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cross-linking Immunoprecipitation
Cross-linking and immunoprecipitation (CLIP, or CLIP-seq) is a method used in molecular biology that combines UV cross-link, crosslinking with immunoprecipitation in order to identify RNA binding sites of proteins on a transcriptome-wide scale, thereby increasing our understanding of post-transcriptional regulatory networks. CLIP can be used either with antibodies against endogenous proteins, or with common peptide tags (including FLAG, V5, HA, and others) or affinity purification, which enables the possibility of profiling model organisms or RBPs otherwise lacking suitable antibodies. Workflow CLIP begins with the ''in vivo'' cross-linking of RNA-protein complexes using ultraviolet light (UV). Upon UV exposure, covalent bonds are formed between proteins and nucleic acids that are in close proximity (on the order of Angstroms apart). The cross-linked cells are then lysed, RNA is fragmented, and the protein of interest is isolated via immunoprecipitation. In order to allow for primi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multipartite Graph
In graph theory, a part of mathematics, a -partite graph is a graph whose vertices are (or can be) partitioned into different independent sets. Equivalently, it is a graph that can be colored with colors, so that no two endpoints of an edge have the same color. When these are the bipartite graphs, and when they are called the tripartite graphs. Bipartite graphs may be recognized in polynomial time but, for any it is NP-complete, given an uncolored graph, to test whether it is -partite. However, in some applications of graph theory, a -partite graph may be given as input to a computation with its coloring already determined; this can happen when the sets of vertices in the graph represent different types of objects. For instance, folksonomies have been modeled mathematically by tripartite graphs in which the three sets of vertices in the graph represent users of a system, resources that the users are tagging, and tags that the users have applied to the resources. A comple ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Matroid
In combinatorics, a matroid is a structure that abstracts and generalizes the notion of linear independence in vector spaces. There are many equivalent ways to define a matroid Axiomatic system, axiomatically, the most significant being in terms of: independent sets; bases or circuits; rank functions; closure operators; and closed sets or ''flats''. In the language of partially ordered sets, a finite simple matroid is equivalent to a geometric lattice. Matroid theory borrows extensively from the terms used in both linear algebra and graph theory, largely because it is the abstraction of various notions of central importance in these fields. Matroids have found applications in geometry, topology, combinatorial optimization, network theory, and coding theory. Definition There are many Cryptomorphism, equivalent ways to define a (finite) matroid. Independent sets In terms of independence, a finite matroid M is a pair (E, \mathcal), where E is a finite set (called the ''gro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thagomizer Graph
In graph theory, a book graph (often written B_p ) may be any of several kinds of graph formed by multiple cycles sharing an edge. Variations One kind, which may be called a quadrilateral book, consists of ''p'' quadrilaterals sharing a common edge (known as the "spine" or "base" of the book). That is, it is a Cartesian product of a star and a single edge. The 7-page book graph of this type provides an example of a graph with no harmonious labeling. A second type, which might be called a triangular book, is the complete tripartite graph ''K''1,1,''p''. It is a graph consisting of p triangles sharing a common edge. A book of this type is a split graph. This graph has also been called a K_e(2,p) or a thagomizer graph (after thagomizers, the spiked tails of stegosaurian dinosaurs, because of their pointy appearance in certain drawings) and their graphic matroids have been called thagomizer matroids. Triangular books form one of the key building blocks of line perfect graph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Othniel Charles Marsh
Othniel Charles Marsh (October 29, 1831 – March 18, 1899) was an American professor of paleontology. A prolific fossil collector, Marsh was one of the preeminent paleontologists of the nineteenth century. Among his legacies are the discovery or description of dozens of new species—including the stegosaurus and triceratops—and theories on the origins of birds. He spent his academic career at Yale College and was president of the National Academy of Sciences. Born into a modest family, Marsh was able to afford higher education thanks to the generosity of his wealthy uncle George Peabody. After graduating from Yale College in 1860 he traveled the world, studying anatomy, mineralogy and geology. He obtained a teaching position at Yale upon his return. From the 1870s to 1890s, he competed with rival paleontologist Edward Drinker Cope in a period of frenzied Western American expeditions known as the Bone Wars. Marsh's greatest legacy is the collection of Mesozoic reptiles, Creta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indiana University Press
Indiana University Press, also known as IU Press, is an academic publisher founded in 1950 at Indiana University that specializes in the humanities and social sciences. Its headquarters are located in Bloomington, Indiana. IU Press publishes approximately 100 new books annually, in addition to 38 academic journals, and maintains a current catalog comprising some 2,000 titles. Indiana University Press primarily publishes in the following areas: African, African American, Asian, cultural, Jewish, Holocaust, Middle Eastern studies, Russian and Eastern European, and women's and gender studies; anthropology, film studies, folklore, history, bioethics, music, paleontology, philanthropy, philosophy, and religion. IU Press undertakes extensive regional publishing under its Quarry Books imprint. History IU Press began in 1950 as part of Indiana University's post-war growth under President Herman B Wells. Bernard Perry, son of Harvard philosophy professor Ralph Barton Per ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allosaurus
''Allosaurus'' ( ) is an extinct genus of theropod dinosaur that lived 155 to 145 million years ago during the Late Jurassic period ( Kimmeridgian to late Tithonian ages). The first fossil remains that could definitively be ascribed to this genus were described in 1877 by Othniel C. Marsh. The name "''Allosaurus''" means "different lizard", alluding to its lightweight , which Marsh believed were unique. The genus has a very complicated taxonomy and includes at least three valid species, the best known of which is ''A. fragilis''. The bulk of ''Allosaurus'' remains come from North America's Morrison Formation, with material also known from the Alcobaça Formation and Lourinhã Formation in Portugal. It was known for over half of the 20th century as '' Antrodemus'', but a study of the abundant remains from the Cleveland-Lloyd Dinosaur Quarry returned the name "''Allosaurus''" to prominence. As one of the first well-known theropod dinosaurs, it has long attracted attention ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Osteomyelitis
Osteomyelitis (OM) is the infectious inflammation of bone marrow. Symptoms may include pain in a specific bone with overlying redness, fever, and weakness. The feet, spine, and hips are the most commonly involved bones in adults. The cause is usually a bacterial infection, but rarely can be a fungal infection. It may occur by spread from the blood or from surrounding tissue. Risks for developing osteomyelitis include diabetes, intravenous drug use, prior splenectomy, removal of the spleen, and trauma to the area. Diagnosis is typically suspected based on symptoms and basic laboratory tests as C-reactive protein and erythrocyte sedimentation rate. This is because plain radiographs are unremarkable in the first few days following acute infection. Diagnosis is further confirmed by blood tests, medical imaging, or bone biopsy. Treatment of bacterial osteomyelitis often involves both antimicrobials and surgery. Treatment outcomes of bacterial osteomyelitis are generally good when t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
