902 resultados para GENERIC SIMPLICITY
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Let f:C-n, 0 --> C-p, 0 be a K-finite map germ, and let i = (i(1),..., i(k)) be a Boardman symbol such that Sigma(i) has codimension n in the corresponding jet space J(k)(n, p). When its iterated successors have codimension larger than n, the paper gives a list of situations in which the number of Sigma(i) points that appear in a generic deformation of f can be computed algebraically by means of Jacobian ideals of f. This list can be summarised in the following way: f must have rank n - i(1) and, in addition, in the case p = 6, f must be a singularity of type Sigma(i2.i2).
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Let f: M --> N and g: K --> N be generic differentiable maps of compact manifolds without boundary into a manifold such that their intersection satisfies a certain transversality condition. We show, under a certain cohomological condition, that if the images f(M) and g(K) intersect, then the (upsilon + 1)th Betti number of their union is strictly greater than the sum of their (upsilon + 1)th Betti numbers, where upsilon = dim M + dim K - dim N. This result is applied to the study of coincidence sets and fixed point sets. (C) 1999 Elsevier B.V. B.V. All rights reserved.
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São descritos o cariótipo e a localização das regiões organizadoras de nucléolo (Ag-NOR) de uma amostra de Trichomycterus diabolus, coletada no córrego Hortelã (Botucatu, São Paulo, Brasil). A espécie apresentou 2n=56 cromossomos (42 metacêntricos, 12 submetacêntricos e 2 subtelocêntricos) e as regiões organizadoras de nucléolo localizadas próximas ao centrômero, no braço longo do maior par metacêntrico. A ocorrência de 2n=56 cromossomos em Trichomycterus diabolus é uma característica interessante, uma vez que, até o momento, todas as espécies cis-Andinas cariotipadas apresentaram 2n=54 cromossomos, enquanto que quase todas as espécies trans-Andinas apresentaram números diplóides diferentes. É discutida a possível origem desta inesperada estrutura cariotípica.
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The generic and subgeneric classification of the family Batrachospermaceae (Rhodophyta) has long been recognized as ambiguous and often inconsistent. One of the prime features used to delineate sections of Batrachospermum, trichogyne shape, is variable even within given species. However, characters associated with the carposporophyte and the carpogonial branch, as well as carpogonial symmetry, are practical and consistent taxonomic criteria. These features have been used to redefine sectional delineation in Batrachospermum. Based on phylogenetic reasoning and practicality, it is proposed that the three genera Nothocladus, Sirodotia and Tuomeya be reduced to sectional level within Batrachospermum. The genus Batrachospermum would thus become the sole member of the Batrachospermaceae and would include two subgenera, Batrachospermum and Acarposporophytum, the former with nine clearly defined sections (Aristata, Batrachospermum, Contorta, Hybrida, Nothocladus (Skuja) stat. nov., Sirodotia (Kylin) stat. nov., Tuomeya (Harvey) stat. nov., Turficola and Viridia). As a result, the following nomenclatural changes are proposed: Batrachospermum lindaueri (Skuja) comb. nov., B. nodosum (Skuja) comb. nov., B. delicatulum (Skuja) comb. nov., B. fennicum (Skuja) comb. nov., B. suecicum (Kylin) comb. nov. and B. americanum (Kutzing) comb. nov.
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The intra-generic inhibition of bacterial growth observed previously in vivo and in vitro with strains of Salmonella, Citrobacter and E. coli was studied in vitro using S. typhimurium strain F98. There was complete inhibition of multiplication of S. typhimurium when it was added to stationary-phase broth cultures of different Salmonella serotypes, but only partial inhibition when added to broth cultures of E. coli. The degree of inhibition between different mutants of F98 was affected by the numbers of bacteria of the inhibiting strain, but this was not the only factor, since exponential-phase bacterial cells were less inhibitory than stationary-phase cells. The inhibitory effect was produced at temperatures between 20°C and 40°C. The complete inhibition of growth observed between F98 mutants was abolished by ampicillin, rifampicin and streptomycin, but not by nalidixic acid. Inhibition was also prevented by separating the two cultures by a dialysis membrane. A Tnpho A Insertion mutant of F98 was produced which did not show inhibition in vitro but was still inhibitory in vivo. It is suggested that this complete inhibition of bacterial multiplication between organisms of the same genus, which is greater than that produced between organisms from different genera, is mediated by a cell surface protein.
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Leptodactylus dantasi Bokermann is redescribed from adult specimens collected in Parque Nacional da Serra do Divisor, State of Acre, Brazil, near the border between the Brazilian state of Acre and Peru. We propose the inclusion of this species in the genus Hydrolaetare. A new diagnostic character observed for the genus is the presence of fringes of fingers, and fringes and webbing of toes, finely serrate; the serrate edge of the fringe and webbing can be keratinized in males, females, and subadults. Hydrolaetare dantasi (Bokermann) is characterized by robust body and limbs, a broad and depressed head, slightly shorter than wide, and long, pointed and basally webbed toes. Hydrolaetare dantasi differs from the only other species in this genus, Hydrolaetare schmidti (Cochran and Goin), mainly by having toes webbed basally (fully webbed in H. schmidti). The advertisement call of H. dantasi is composed of two components; an initial note produced by the impact of the vocal sac against the ground and a second note corresponding to a long whistle of ascending frequency. The initial note is a percussive sound and represents an unusual form of sound emission in anurans; the second note is a vocalization.
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Five species of feather mites originally described in the genus Pterodectes by Vladimir černý (1974) are redescribed: Pterodectes havliki, P. maculatus , P. reticulatus, P. storkani, P. thraupicola and P. troglodytis. The formerly unknown males of P. thraupicola and P. reticulatus and the female of P. maculatus are described for the first time. A synopsis of known species of the Pterodectes generic complex is presented, and species content of the genus Pterodectes is revised. Fifteen species previously included in this genus are transferred to the new genus Amerodectes gen. n.: Amerodectes atyeoi (OConnor et al., 2005) comb. n., A. bilineatus (Berla, 1958) comb. n., A. geothlypis (Berla, 1973) comb. n., A. gracilis (Trouessart, 1885) comb. n., A. maculatus comb. n., A. molothrus (Mironov, 2008) comb. n., A. nordestensis (Berla, 1958) comb. n., A. paroariae (Mironov, 2008) comb. n., A. pitangi (Mironov, 2008) comb. n., A. tangarae (Mironov, 2008) comb. n., A. turdinus (Berla, 1959) comb. n., A. sialiarum (Stoll, 1893) comb. n., A. storkani (černý, 1974) comb. n., A. thraupicola (cčerný, 1974) comb. n., and A. troglodytis (černý, 1974) comb. n. Five species are transferred to the genus Tyrannidectes Mironov, 2008: Tyrannidectes amaurochalinus (Hernandes et Valim, 2006) comb. n., T. banksi (Valim et Hernandes, 2008) comb. n., T. crassus (Trouessart, 1885) comb. n., T. fissuratus (Hernandes et Valim, 2005) comb. n., and T. reticulatus (Cerný, 1974) comb. n.; and one species is moved to the genus Metapterodectes Mironov, 2008: Metapterodectes muticus (Banks, 1909) comb. n. The genus Pterodectes remains monotypic, with the type species P. rutilus Robin, 1877. © Acarina 2010.
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In this article we discuss some qualitative and geometric aspects of non-smooth dynamical systems theory. Our goal is to study the diagram bifurcation of typical singularities that occur generically in one parameter families of certain piecewise smooth vector fields named Refracted Systems. Such systems has a codimension-one submanifold as its discontinuity set. © 2012 Elsevier Ltd.
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Esta tese de doutorado propõe uma formulação matemática para simulação de roteamento e alocação de comprimentos de onda em redes ópticas, sem a inclusão de restrições que não são inerentes ao problema básico e com o objetivo de ser aplicável a qualquer tipo de rede óptica com tráfego de demanda estática. O estabelecimento de uma rota seguida da seleção de um comprimento de onda é um dos pontos chave para o bom funcionamento de uma rede óptica, pois influencia na forma como os recursos da rede serão gerenciados. Assim, o processo de roteamento e alocação de comprimentos de onda em redes ópticas, conhecido como RWA (Routing and Wavelength Assignment), necessita de soluções que busquem a sua otimização. Entretanto, a despeito dos inúmeros estudos com o objetivo de otimizar o processo RWA, observa-se que não há, a priori, nenhuma solução que possa levar a uma padronização do referido processo. Considerando que a padronização é desejável na consolidação do uso de qualquer tecnologia, a Tese descrita neste trabalho é uma Função de Objetivo Genérico (FOG) que trata do processo de roteamento e alocação de comprimentos de onda, visando estabelecer uma base a partir da qual seja possível desenvolver um padrão ou vários padrões para redes ópticas. A FOG foi testada, via simulação, no processo de alocação de comprimentos de onda do inglês, Wavelength Assignment e no processo RWA como um todo. Em ambos os casos, os testes foram realizados considerando redes opacas, trazendo resultados surpreendentes, considerando a simplicidade da solução para um problema não trivial.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Heterogeneous waveband switching (HeteroWBS) in WDM networks reduces the network operational costs. We propose an autonomous clustering-based HeteroWBS architecture to support the design of efficient HeteroWBS algorithms under dynamic traffic requests in such a network.
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Platycoelia bicolor (Gutiérrez) (Scarabaeidae: Rutelinae) is transferred from the tribe Anoplognathini, subtribe Platycoeliina, to the tribe Rutelini. Platycoelia bicolor is placed in the genus Eremophygus Ohaus and the taxonomic history of the species is discussed. The transfer creates a new combination, Eremophygus bicolor (Gutiérrez) and places the generic name Heterocallichloris Gutiérrez as a junior synonym of Eremophygus (new synonymy). Morphological characters that warrant the transfer are discussed. Se transfiere Platycoelia bicolor (Gutiérrez) (Scarabaeidae: Rutelinae) de la tribu Anoplognathini, subtribe Platycoeliina, a la tribu Rutelini. Se transfiere Platycoelia bicolor al género Eremophygus Ohaus y se discute su historia taxonómica. La transferencia crea una nueva combinación, Eremophygus bicolor (Gutiérrez) y ubica al nombre genérico Heterocallichloris Gutiérrez como un sinónimo junior de Eremophygus. Se discuten los caracteres morfológicos que justifican la transferencia.
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Low-molecular-weight heparins (LMWHs) have shown equivalent or superior efficacy and safety to unfractionated heparin as antithrombotic therapy for patients with acute coronary syndromes. Each approved LMWH is a pleotropic biological agent with a unique chemical, biochemical, biophysical and biological profile and displays different pharmacodynamic and pharmacokinetic profiles. As a result, LMWHs are neither equipotent in preclinical assays nor equivalent in terms of their clinical efficacy and safety. Previously, the US Food and Drug Administration (FDA) cautioned against using various LMWHs interchangeably, however recently, the FDA approved generic versions of LMWH that have not been tested in large clinical trials. This paper highlights the bio-chemical and pharmacological differences between the LMWH preparations that may result in different clinical outcomes, and also reviews the implications and challenges physicians face when generic versions of the original/innovator agents are approved for clinical use.