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Tendril Perversion
Tendril perversion is a geometric phenomenon sometimes observed in helical structures in which the direction of the helix transitions between left-handed and right-handed. Such a reversal of chirality is commonly seen in helical plant tendrils and telephone handset cords. The phenomenon was known to Charles Darwin, who wrote in 1865, The term "tendril perversion" was coined by Alain Goriely and Michael Tabor in 1998 based on the word ''perversion'' found in 19th-century science literature. "Perversion" is a transition from one chirality to another and was known to James Clerk Maxwell, who attributed it to topologist J. B. Listing. Tendril perversion can be viewed as an example of spontaneous symmetry breaking, in which the strained structure of the tendril adopts a configuration of minimum energy while preserving zero overall twist. Tendril perversion has been studied both experimentally and theoretically. Gerbode et al. have made experimental studies of the coiling ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PSM V17 D663 A Caught Tendril Of Bryonia Dioica
PSM, an acronym, may refer to: Organizations * Pakistan School Muscat, a Pakistani co-educational institute in Oman * Palestine Solidarity Movement, a student organization in the United States * Panhellenic Socialist Movement, a centre-left party in Greece * Parti Socialiste Mauricien, a political party in Mauritius, founded by Harish Boodhoo * Parti Sosialis Malaysia, a socialist political party in Malaysia * Sepaktakraw Association of Malaysia (; PSM), a national governing body in Malaysia * Photographic Society of Madras, a not for profit organisation involved in promoting photography, in Chennai * PlayStation: The Official Magazine, a magazine originally known as PlayStation Magazine or PSM * Ponce School of Medicine, a post-graduate medical school located in Ponce, Puerto Rico * Power Systems Manufacturing, a subsidiary of Alstom, specializing in aftermarket gas turbine servicing for power generating industry. * ''Poznańska Spółdzielnia Mieszkaniowa'', a housing cooperativ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Topologist
Topology (from the Greek words , and ) is the branch of mathematics concerned with the properties of a geometric object that are preserved under continuous deformations, such as stretching, twisting, crumpling, and bending; that is, without closing holes, opening holes, tearing, gluing, or passing through itself. A topological space is a set endowed with a structure, called a ''topology'', which allows defining continuous deformation of subspaces, and, more generally, all kinds of continuity. Euclidean spaces, and, more generally, metric spaces are examples of topological spaces, as any distance or metric defines a topology. The deformations that are considered in topology are homeomorphisms and homotopies. A property that is invariant under such deformations is a topological property. The following are basic examples of topological properties: the dimension, which allows distinguishing between a line and a surface; compactness, which allows distinguishing between a line ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Curves
A curve is a geometrical object in mathematics. Curve(s) may also refer to: Arts, entertainment, and media Music * Curve (band), an English alternative rock music group * Curve (album), ''Curve'' (album), a 2012 album by Our Lady Peace * Curve (song), "Curve" (song), a 2017 song by Gucci Mane featuring The Weeknd * ''Curve'', a 2001 album by Doc Walker * "Curve", a song by John Petrucci from ''Suspended Animation (John Petrucci album), Suspended Animation'', 2005 * "Curve", a song by Cam'ron from the album ''Crime Pays (Cam'ron album), Crime Pays'', 2009 Periodicals * Curve (design magazine), ''Curve'' (design magazine), an industrial design magazine * Curve (magazine), ''Curve'' (magazine), a U.S. lesbian magazine Other uses in arts, entertainment, and media * Curve (film), ''Curve'' (film), a 2015 film * BBC Two "Curve" idents, various animations based around a curve motif Brands and enterprises *Curve (payment card), a payment card that aggregates multiple payment cards * Cu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helices
A helix (; ) is a shape like a cylindrical coil spring or the thread of a machine screw. It is a type of smoothness (mathematics), smooth space curve with tangent lines at a constant angle to a fixed axis. Helices are important in biology, as the DNA molecule is formed as double helix, two intertwined helices, and many proteins have helical substructures, known as alpha helix, alpha helices. The word ''helix'' comes from the Greek language, Greek word , "twisted, curved". A "filled-in" helix – for example, a "spiral" (helical) ramp – is a surface called a ''helicoid''. Properties and types The pitch of a helix is the height of one complete helix turn (angle), turn, measured parallel to the axis of the helix. A double helix consists of two (typically congruence (geometry), congruent) helices with the same axis, differing by a translation along the axis. A circular helix (i.e. one with constant radius) has constant band curvature and constant Torsion of curves, torsion. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemihelix
A hemihelix is a curved geometric shape consisting of a series of helices with alternating chirality, connected by a perversion Perversion is a form of human behavior which is far from what is considered to be orthodoxy, orthodox or Normality (behavior), normal. Although the term ''perversion'' can refer to a variety of forms of ''deviation'', it is most often used to desc ... at the reversals. The formation of hemihelices with periodic distributions of perversions in slender structures is understood in terms of competing buckling instabilities generated by in-plane stresses. References External links * Helices Geometric shapes Curves Articles containing video clips {{physics-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helical Growth
Helical growth is when cells or organs expand, resulting in helical shaped cells or organs and typically including the breakage of symmetry. This is seen in fungi, algae, and other higher plant cells or organs. Helical growth can occur naturally, such as in tendrils or in twining plants. Asymmetry can be caused by changes in pectin or through mutation and result in left- or right-handed helices. Tendril perversion, during which a tendril curves in opposite directions at each end, is seen in many cases. The helical growth of twining plants is based on the circumnutational movement, or circular growth, of stems. Most twining plans have right-handed helices regardless of the plant's growth hemisphere. Helical growth in single cells, such as the fungi genus ''Phycomyces'' or the algae genus ''Nitella'', is thought to be caused by a helical arrangement of structural biological material in the cell wall. In mutant thale cress, helical growth is seen at the organ level. Analysis stron ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cucumber
The cucumber (''Cucumis sativus'') is a widely-cultivated creeping vine plant in the family Cucurbitaceae that bears cylindrical to spherical fruits, which are used as culinary vegetables.Cucumber " ''''. 9982019. Considered an annual plant, there are three main types of cucumber—slicing, pickling, and seedless—within which several |
Minimum Total Potential Energy Principle
In mathematical analysis, the maximum and minimum of a function are, respectively, the greatest and least value taken by the function. Known generically as extremum, they may be defined either within a given range (the ''local'' or ''relative'' extrema) or on the entire domain (the ''global'' or ''absolute'' extrema) of a function. Pierre de Fermat was one of the first mathematicians to propose a general technique, adequality, for finding the maxima and minima of functions. As defined in set theory, the maximum and minimum of a set are the greatest and least elements in the set, respectively. Unbounded infinite sets, such as the set of real numbers, have no minimum or maximum. In statistics, the corresponding concept is the sample maximum and minimum. Definition A real-valued function ''f'' defined on a domain ''X'' has a global (or absolute) maximum point at ''x''∗, if for all ''x'' in ''X''. Similarly, the function has a global (or absolute) minimum point at ''x''∗ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spontaneous Symmetry Breaking
Spontaneous symmetry breaking is a spontaneous process of symmetry breaking, by which a physical system in a symmetric state spontaneously ends up in an asymmetric state. In particular, it can describe systems where the equations of motion or the Lagrangian obey symmetries, but the lowest-energy vacuum solutions do not exhibit that same symmetry. When the system goes to one of those vacuum solutions, the symmetry is broken for perturbations around that vacuum even though the entire Lagrangian retains that symmetry. Overview The spontaneous symmetry breaking cannot happen in quantum mechanics that describes finite dimensional systems, due to Stone-von Neumann theorem (that states the uniqueness of Heisenberg commutation relations in finite dimensions). So spontaneous symmetry breaking can be observed only in infinite dimensional theories, as quantum field theories. By definition, spontaneous symmetry breaking requires the existence of physical laws which are invariant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
James Clerk Maxwell
James Clerk Maxwell (13 June 1831 – 5 November 1879) was a Scottish physicist and mathematician who was responsible for the classical theory of electromagnetic radiation, which was the first theory to describe electricity, magnetism and light as different manifestations of the same phenomenon. Maxwell's equations for electromagnetism achieved the Unification (physics)#Unification of magnetism, electricity, light and related radiation, second great unification in physics, where Unification (physics)#Unification of gravity and astronomy, the first one had been realised by Isaac Newton. Maxwell was also key in the creation of statistical mechanics. With the publication of "A Dynamical Theory of the Electromagnetic Field" in 1865, Maxwell demonstrated that electric force, electric and magnetic fields travel through space as waves moving at the speed of light. He proposed that light is an undulation in the same medium that is the cause of electric and magnetic phenomena. (Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cucurbita Pepo 02 Ies
is a genus of herbaceous fruits in the gourd family, Cucurbitaceae (also known as ''cucurbits'' or ''cucurbi''), native to the Andes and Mesoamerica. Five edible species are grown and consumed for their flesh and seeds. They are variously known as squash, pumpkin, or gourd, depending on species, variety, and local parlance. Other kinds of gourd, also called bottle-gourds, are native to Africa and belong to the genus ''Lagenaria'', which is in the same family and subfamily as ''Cucurbita'', but in a different tribe; their young fruits are eaten much like those of the ''Cucurbita'' species. Most ''Cucurbita'' species are herbaceous vines that grow several meters in length and have tendrils, but non-vining "bush" cultivars of ''C. pepo'' and ''C. maxima'' have also been developed. The yellow or orange flowers on a ''Cucurbita'' plant are of two types: female and male. The female flowers produce the fruit and the male flowers produce pollen. Many North and Central America ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alain Goriely
Alain Goriely is a Belgian mathematician, currently holding the statutory professorship (chair) of mathematical modelling at the University of Oxford, Mathematical Institute. He is director of the Oxford Centre for Industrial Mathematics (OCIAM), of the International Brain and Mechanics Lab (IBMTL) and Professorial Fellow at St Catherine's College, Oxford. At the Mathematical Institute, he was the director of external relations and public engagement, from 2013 until 2022, initiating the Oxford Mathematics series of public lectures. In 2022, he was elected to the Royal Society, and Gresham Professor of Geometry at the Gresham College (London) in 2024. Education and early life Born and raised in Brussels, Goriely obtained his B.Sc. in 1989 and Ph.D. in 1994 from the Université libre de Bruxelles where he became lecturer in the Mathematics Department. Shortly after, he moved to the University of Arizona to take the positions of Research Associate (1994-1997), Assistant Professo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
