941 resultados para Differential calculus in Banach spaces


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The paradigm of ubiquitous computing has become a reference for the design of Smart Spaces. Current trends in Ambient Intelligence are increasingly related to the scope of Internet of Things. This paradigm has the potential to support cost-effective solutions in the fields of telecare, e-health and Ambient Assisted Living. Nevertheless, ubiquitous computing does not provide end users with a role for proactive interactions with the environment. Thus, the deployment of smart health care services at a private space like the home is still unsolved. This PhD dissertation aims to define a person-environment interaction model to foster acceptability and users confidence in private spaces by applying the concept of user-centred security and the human performance model of seven stages of action.

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Let P be a system of n linear nonhomogeneous ordinary differential polynomials in a set U of n-1 differential indeterminates. Differential resultant formulas are presented to eliminate the differential indeterminates in U from P. These formulas are determinants of coefficient matrices of appropriate sets of derivatives of the differential polynomials in P, or in a linear perturbation Pe of P. In particular, the formula dfres(P) is the determinant of a matrix M(P) having no zero columns if the system P is ``super essential". As an application, if the system PP is sparse generic, such formulas can be used to compute the differential resultant dres(PP) introduced by Li, Gao and Yuan.

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La tesis Asplund versus Lewerentz analiza, por el método comparado, los invariantes, las convergencias y las divergencias entre las obras de los arquitectos suecos Erik Gunnar Asplund y Sigurd Lewerentz. Autores del Cementerio del Bosque de Estocolmo, que desarrollaron en colaboración durante más de veinte años, supone una de las obras maestras de la arquitectura escandinava, y uno de los ejemplos de referencia para entender la cultura arquitectónica nórdica moderna en relación a su tradición. Del estudio contrastado de los distintos proyectos y versiones del cementerio, ejecutados conjuntamente o por separado, se obtienen los valores compartidos entre ambos arquitectos, así como sus afinidades o diferencias respecto a un mismo tema. Estos aspectos, extrapolados al resto de sus trabajos, permiten entender sus actuaciones según las referencias e influencias mutuas, y la definición de las variables que configuran sus respectivos espacios arquitectónicos. La investigación se ha estructurado en ocho capítulos: La Escuela Klara, que trata la relación de Asplund y Lewerentz en su época de estudiantes, así como la influencia de sus maestros respectivos; El Grand Tour, que analiza sus viajes y las miradas de cada uno de ellos en sus visitas a los mismos lugares; Los Estudios, que profundiza en sus caracteres, reflejados a través de la comparación de los distintos lugares de trabajo; Las Tumbas, donde se concretan a pequeña escala los temas desarrollados ampliamente en el Cementerio del Bosque, constituyendo así un laboratorio de ideas; La Exposición de Estocolmo de 1930, que vuelve a aclarar las posturas divergentes de ambos, en este caso, en relación a un tema lúdico, y que supuso un giro de su arquitectura y, con ello, un importante apoyo a los cambios sociales del momento; Los Concursos, realizados por separado, donde se observan con precisión las afinidades y las diferencias respecto a un mismo planteamiento inicial; Los Accesos del Cementerio del Bosque, que supone un trabajo conjunto con alternancia de decisiones, en el que se perfila con claridad los intereses específicos de ambos; y por último, las Capillas del Cementerio del Bosque, especialmente la Capilla del Bosque y de la Resurrección, que concretan, en los dos lugares más íntimos del cementerio, las ideas y personalidades opuestas de Asplund y Lewerentz en relación al tema común de la muerte. Las conclusiones de este estudio comparado y centrado en varios temas, determinan una confluencia de intereses en la conexión de sus obras con la topografía como medio de contextualización, en las acciones sobre la vegetación como un aspecto fundamental y no sólo como un acompañamiento a la arquitectura, y en la manipulación de la luz como hecho diferencial del carácter de los distintos espacios. Se reúnen así en esta tesis unas constantes del trabajo de Asplund y Lewerentz, que planteadas muchas veces de forma distinta, apuntan directamente a los sentimientos del Hombre en el momento de la muerte y ante una despedida en relación a la Arquitectura. ABSTRACT The thesis Asplund versus Lewerentz analyses, by means of comparative methodology, the constants, the convergences and the divergences between the works of the Swedish architects Erik Gunnar Asplund and Sigurd Lewerentz. They are the authors of Stockholm’s Woodland Cemetery, which they developed in collaboration over a period of more than twenty years, one of the masterpieces of Swedish architecture and one of the key examples in terms of understanding modern Nordic architectural culture in relation to its tradition. From the contrasted study of the various projects and versions of the cemetery, executed jointly or separately, one obtains the values shared by both architects as well as their affinities or differences with respect to one and the same theme. These aspects, extrapolated from the rest of their works, permit an understanding of their actions according to mutual references and influences, and the definition of the variables that shape their respective architectural spaces. The research is divided into eight chapters: The Klara School, dealing with Asplund and Lewerentz’s relationship during their student days, as well as the influence of their respective teachers; The Grand Tour, which analyses their travels and the viewpoints of each of them on their visits to the same places; The Studies, looks closely at their personalities, reflected by a comparison of their different workplaces; The Tombs, where the themes extensively developed in the Woodland Cemetery are set out on a small scale, thus constituting one of their laboratories of ideas; The Stockholm exhibition of 1930, which again clarifies the diverging postures of the two, in this case, in relation to a recreational topic which represented a turnabout in their architecture and, moreover an important support for the social changes of the age; The Competitions, which they carried out separately, where one closely observes affinities and differences with respect to an initial approach; The Accesses to the Woodland Cemetery, which represents a joint work with alternating decision-making, in which the interests of both are clearly outlined; and finally, the Chapels of the Woodland Cemetery, especially the Woodland Chapel and the Chapel of the Resurrection, which, in the two most intimate spots in the cemetery, embody the opposing ideas and personalities of Asplund and Lewerentz in relation to the common theme of death. The conclusions of this comparative study centred on various topics, determine a confluence of interests in the connection of their works with the topography as a means of contextualization, in actions relating to vegetation as a fundamental aspect and not just an accompaniment to architecture, and in the manipulation of light as a differential factor in the character of the different spaces. Thus this thesis brings together some of the constants of the work of Asplund and Lewerentz which, frequently dealt with in a different manner, point directly to Man’s feelings at the point of death and in the face of a farewell in relation to Architecture.

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We present a compact formula for the derivative of a 3-D rotation matrix with respect to its exponential coordinates. A geometric interpretation of the resulting expression is provided, as well as its agreement with other less-compact but better-known formulas. To the best of our knowledge, this simpler formula does not appear anywhere in the literature. We hope by providing this more compact expression to alleviate the common pressure to reluctantly resort to alternative representations in various computational applications simply as a means to avoid the complexity of differential analysis in exponential coordinates.

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This paper presents the design and characterization process of an active array demonstrator for the mid-frequency range (i.e., 300 MHz-1000 MHz) of the future Square Kilometre Array (SKA) radio telescope. This demonstrator, called FIDA3 (FG-IGN: Fundación General Instituto Geográfico Nacional - Differential Active Antenna Array), is part of the Spanish contribution for the SKA project. The main advantages provided by this design include the use of a dielectric-free structure, and the use of a fully-differential receiver in which differential low-noise amplifiers (LNAs) are directly connected to the balanced tapered-slot antennas (TSAs). First, the radiating structure and the differential low-noise amplifiers were separately designed and measured, obtaining good results (antenna elements with low voltage standing-wave ratios, array scanning capabilities up to 45°, and noise temperatures better than 52 K with low-noise amplifiers at room temperature). The potential problems due to the differential nature of the proposed solution are discussed, so some effective methods to overcome such limitations are proposed. Second, the complete active antenna array receiving system was assembled, and a 1 m2 active antenna array tile was characterized.

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La tesis Asplund versus Lewerentz analiza, por el método comparado, los invariantes, las convergencias y las divergencias entre las obras de los arquitectos suecos Erik Gunnar Asplund y Sigurd Lewerentz. Autores del Cementerio del Bosque de Estocolmo, que desarrollaron en colaboración durante más de veinte años, supone una de las obras maestras de la arquitectura escandinava, y uno de los ejemplos de referencia para entender la cultura arquitectónica nórdica moderna en relación a su tradición. Del estudio contrastado de los distintos proyectos y versiones del cementerio, ejecutados conjuntamente o por separado, se obtienen los valores compartidos entre ambos arquitectos, así como sus afinidades o diferencias respecto a un mismo tema. Estos aspectos, extrapolados al resto de sus trabajos, permiten entender sus actuaciones según las referencias e influencias mutuas, y la definición de las variables que configuran sus respectivos espacios arquitectónicos. La investigación se ha estructurado en ocho capítulos: La Escuela Klara, que trata la relación de Asplund y Lewerentz en su época de estudiantes, así como la influencia de sus maestros respectivos; El Grand Tour, que analiza sus viajes y las miradas de cada uno de ellos en sus visitas a los mismos lugares; Los Estudios, que profundiza en sus caracteres, reflejados a través de la comparación de los distintos lugares de trabajo; Las Tumbas, donde se concretan a pequeña escala los temas desarrollados ampliamente en el Cementerio del Bosque, constituyendo así un laboratorio de ideas; La Exposición de Estocolmo de 1930, que vuelve a aclarar las posturas divergentes de ambos, en este caso, en relación a un tema lúdico, y que supuso un giro de su arquitectura y, con ello, un importante apoyo a los cambios sociales del momento; Los Concursos, realizados por separado, donde se observan con precisión las afinidades y las diferencias respecto a un mismo planteamiento inicial; Los Accesos del Cementerio del Bosque, que supone un trabajo conjunto con alternancia de decisiones, en el que se perfila con claridad los intereses específicos de ambos; y por último, las Capillas del Cementerio del Bosque, especialmente la Capilla del Bosque y de la Resurrección, que concretan, en los dos lugares más íntimos del cementerio, las ideas y personalidades opuestas de Asplund y Lewerentz en relación al tema común de la muerte. Las conclusiones de este estudio comparado y centrado en varios temas, determinan una confluencia de intereses en la conexión de sus obras con la topografía como medio de contextualización, en las acciones sobre la vegetación como un aspecto fundamental y no sólo como un acompañamiento a la arquitectura, y en la manipulación de la luz como hecho diferencial del carácter de los distintos espacios. Se reúnen así en esta tesis unas constantes del trabajo de Asplund y Lewerentz, que planteadas muchas veces de forma distinta, apuntan directamente a los sentimientos del Hombre en el momento de la muerte y ante una despedida en relación a la Arquitectura. ABSTRACT The thesis Asplund versus Lewerentz analyses, by means of comparative methodology, the constants, the convergences and the divergences between the works of the Swedish architects Erik Gunnar Asplund and Sigurd Lewerentz. They are the authors of Stockholm’s Woodland Cemetery, which they developed in collaboration over a period of more than twenty years, one of the masterpieces of Swedish architecture and one of the key examples in terms of understanding modern Nordic architectural culture in relation to its tradition. From the contrasted study of the various projects and versions of the cemetery, executed jointly or separately, one obtains the values shared by both architects as well as their affinities or differences with respect to one and the same theme. These aspects, extrapolated from the rest of their works, permit an understanding of their actions according to mutual references and influences, and the definition of the variables that shape their respective architectural spaces. The research is divided into eight chapters: The Klara School, dealing with Asplund and Lewerentz’s relationship during their student days, as well as the influence of their respective teachers; The Grand Tour, which analyses their travels and the viewpoints of each of them on their visits to the same places; The Studies, looks closely at their personalities, reflected by a comparison of their different workplaces; The Tombs, where the themes extensively developed in the Woodland Cemetery are set out on a small scale, thus constituting one of their laboratories of ideas; The Stockholm exhibition of 1930, which again clarifies the diverging postures of the two, in this case, in relation to a recreational topic which represented a turnabout in their architecture and, moreover an important support for the social changes of the age; The Competitions, which they carried out separately, where one closely observes affinities and differences with respect to an initial approach; The Accesses to the Woodland Cemetery, which represents a joint work with alternating decision-making, in which the interests of both are clearly outlined; and finally, the Chapels of the Woodland Cemetery, especially the Woodland Chapel and the Chapel of the Resurrection, which, in the two most intimate spots in the cemetery, embody the opposing ideas and personalities of Asplund and Lewerentz in relation to the common theme of death. The conclusions of this comparative study centred on various topics, determine a confluence of interests in the connection of their works with the topography as a means of contextualization, in actions relating to vegetation as a fundamental aspect and not just an accompaniment to architecture, and in the manipulation of light as a differential factor in the character of the different spaces. Thus this thesis brings together some of the constants of the work of Asplund and Lewerentz which, frequently dealt with in a different manner, point directly to Man’s feelings at the point of death and in the face of a farewell in relation to Architecture.

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Differential resultant formulas are defined, for a system $\cP$ of $n$ ordinary Laurent differential polynomials in $n-1$ differential variables. These are determinants of coefficient matrices of an extended system of polynomials obtained from $\cP$ through derivations and multiplications by Laurent monomials. To start, through derivations, a system $\ps(\cP)$ of $L$ polynomials in $L-1$ algebraic variables is obtained, which is non sparse in the order of derivation. This enables the use of existing formulas for the computation of algebraic resultants, of the multivariate sparse algebraic polynomials in $\ps(\cP)$, to obtain polynomials in the differential elimination ideal generated by $\cP$. The formulas obtained are multiples of the sparse differential resultant defined by Li, Yuan and Gao, and provide order and degree bounds in terms of mixed volumes in the generic case.

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Alison Margaret Gill y Peter Denham Smithson son, o eran, ambos murieron hace ya algunos años, dos arquitectos. Así dicho, esto suena a obviedad. Sin embargo no lo es, porque siempre han sido compactados en una unidad proyectual, bien bajo las siglas Alison y Peter Smithson, o bien, más puntualmente todavía, como los Smithson. Cuando Leibniz en 1696 le dice a la princesa electora Sofía que en algo tan puntual y homogéneo aparentemente como una gota de agua, vista al microscopio, resulta haber más de un millón de animales vivos, se puede empezar a vislumbrar el resultado de la Tesis. El resultado de este trabajo no se contempla un millón de partículas pero sí dos. La obra de Alison y Peter Smithson esta conformada desde su inicio probablemente por la particularidad de que en ella intervienen tanto Gill como Smithson, aunque cada uno sea en mayor o menor medida la o el responsable de un proyecto. Puesto al microscopio el proyecto del que se ocupa la Tesis, el concurso de 1953 para la ampliación de la Universidad de Sheffield, se estima que está compuesto de dos partes diferentes y que como Los Smithson o como una gota de agua, su unidad es una mera convención, una forma de designarlo y tratarlo, que falsea en algo su apreciación, aunque, como se verá, es lo que provoca el extraño efecto que como imagen ejerce. El Capítulo I descubre la duplicidad. Reyner Banham fijó en 1955, en el artículo The New Brutalism, el modo de encarar el proyecto de Sheffield cuando proyectó sobre él lo más novedoso que en el campo de la pintura ocurría en ese momento, el Art Autre. Michel Tapié ve en el informalismo presente en las obras que él engloba como un <> rasgos que puede presentar a la luz de conceptos que extrae de Riemann, matemático del s. XIX, introductor de una nueva geometría. La Tesis remonta por tanto hasta Riemann, a la búsqueda del concepto del que penden tanto Tapié como Banham. El concepto es la variedad continua; un conjunto, cuyos elementos pueden recorrer la extensión de la variedad mediante una deformación continua, como si dijéramos, diluyéndose unos en otros sin cortes entre sí. Los ejemplos del informalismo serían, por tanto, los puntos de la variedad, formas inestables o detenciones aleatorias en este transitar continuo de un mismo objeto. La visión de cuerpos en cortes aleatorios a la evolución otorga a sus formas cualesquiera la condición de extrañeza o perturbación, produciendo un impacto en la mente que lo graba instintivamente en la materia de la memoria. Así, es la memorabilidad, dada precisamente por el impacto que supone ver cuerpos en estado evolutivo, sin una forma precisa, la propiedad que gobierna a los objetos que caen bajo el Art Autre, y es la memorabilidad el rasgo distintivo de Sheffield para Banham. Este sentido evolutivo que se puede asociar a los elementos de una variedad entra en consonancia con una variedad de estados en evolución en el marco de las especies orgánicas. No sólo como individuo sino también como especie. La coincidencia no sólo es formal, también es temporal entre el descubrimiento de Riemann de la variedad continua y el de Darwin de la evolución de las especies. Ve Darwin que algunos ejemplares presentan en su cuerpo conformaciones normales de especies diferentes, que puede entenderse como una anormalidad o defecto evolutivo, lo que él llama <>. Un ejemplar monstruoso no es capaz de abrir una escisión de la variedad y en este sentido rompe su cadena evolutiva. Es un elemento, por tanto extraño a la variedad. Lo peculiar que expone Darwin, es que la monstruosidad puede ser provocada artificialmente por motivos estéticos, como ocurre en determinados animales o plantas ornamentales. Bien, esto es exactamente lo que descubre la Tesis en el proyecto de Sheffield. La unión en un solo proyecto de dos conformaciones de naturaleza diferente. El Capítulo II indaga en la naturaleza dual de Sheffield. Y la descubre en la aplicación de dos principios que tienen múltiples derivas, pero interesante en una en particular, referida al espacio. Uno es el Principio de Posición. Bajo él se contempla la situación del concurso dada en su globalidad, en una visión totalizadora que permite buscar y destacar posiciones singulares y tener un control preciso del proyecto desde el inicio. Se dice que es la opción normal en arquitectura comprender el espacio en su conjunto y que el trazado de ejes y el reparto del espacio obedecen a este principio. Son así vistos la propuesta ganadora del equipo GMW y fundamentalmente el trazado de ejes en la obra de Le Corbusier. Una parte de Sheffield es un producto típico de este modo de proceder. Hay un segundo principio que es el Principio de Transición Continua. En los términos expuestos para la variedad de Riemann, sería como si en lugar de ver cuerpos en estados concretos, por deformados que pudieran ser, nos introdujéramos dentro de la propia variedad acoplándonos al curso de la evolución misma, en un acto de unión interior con la marcha de la evolución. Para ejercer esta acción se toma como punto inicial el extremo del edificio universitario existente, el Firth Court, y se lleva cabo un estiramiento continuo. En esto radica lo que la Tesis distingue como la ampliación, el cuerpo que se enrosca paulatinamente. Para exponer este concepto, la Tesis se apoya en un ejercicio llevado a cabo por Raymond Unwin en Hampstead, el close, o estiramiento lateral del borde de un viario para hacer surgir el espacio útil residencial. A partir del concepto de close, se deriva en la urbanística americana de principios del s. XX el concepto de cluster, que pasa a ser uno de los argumentos principales de la teoría de Alison y de Peter Smithson en los años 50. El Capítulo III plantea la dificultad de mantener la dualidad de Sheffield a primeros de los 50, sometido el proyecto de arquitectura a la unicidad que impone el criterio hegemónico de Rudolf Wittkower desde “Los Fundamentos de la Arquitectura en la Edad del Humanismo”. Como en el Capítulo I, la obligación que se traza la Tesis es remontar los orígenes de las cosas que se tratan, y en este caso, entrar en las fuentes del principio proporcional. Se descubren así los fundamentos de la proporción aritmética y geométrica en el seno del pitagorismo, sus problemas y su evolución. La postura de los dos arquitectos frente a Wittkower es de admiración, pero también de libertad. Esta libertad suya es la que defiende la Tesis. Cotejando lo que da de sí la arquitectura basada en los principios proporcionales con otra arquitectura estancada en el paso del Renacimiento al Barroco como es la arquitectura perspectiva y proyectiva, la arquitectura oblicua, recuperada a la sazón por medio de la intervención en la Tesis de Panofsky, se dirimen aspectos colaterales pero fundamentales de una renovación de los planteamientos: hay planteamientos que se dicen esencialistas y objetivos y otros funcionales y que derivan en subjetivos y relacionales. Sobre estas dos marcos de categorías el propósito que persigue la Tesis es dar cuenta de los dos principios que rigen lo visto en el Capítulo II, el Principio de Posición y el Principio de Transición Continua, responsables ambos, al 50%, de la monstruosidad detectada en Sheffield, que no es negativa, sino, como decía Darwin, la combinación en un solo cuerpo de conformaciones normales en animales de especies diferentes, incluso con fines estéticos. En Sheffield existe, y esta dibujada, la figura de una cabeza escultural con un doble rostro. Todo el trabajo de la Tesis se encamina, en definitiva, a explicar, con toda la claridad y extensión que me ha sido posible, en qué consiste ese doble rostro. ABSTRACT Peter and Alison Smithson’s work is, is from its start, very influenced by both Alison Margaret Gill and Peter Denham Smithson. The matter of study of this Thesis, the 1953 competition for the expansion of the University of Sheffield, estimated after its exam, which is composed by two different parts, which, together produce a strange effect as an image. Reyner Banham in 1955 described the image in his article “The New Brutalism” as the key argument (most iconic) for the Sheffield’s project. The way his image powerfully influences sensitivity, by perturbation, makes this a singular and memorable image. This feature, only present in Sheffield, over any other building of the time, even from the same architects, allow Banham to associate the project to Art Autre, thought by Michel Tapié as a new artistic movement, to which Sheffield will belong, in the architecture part. Tapié sees in the informalism of works considered Art Autre some aspects that can bring concepts he extracts from Riemann, XIX Century mathematician, father of the new geometry. This Thesis discovers Riemann’s concept of continuous variety, a set whose elements are able to go through variety by a continuous deformation, diluting themselves without touching each other. Examples of informalism would be, points of that variety, unstable forms or random detentions in the continuous transit of the same object. Therefore, the condition of memorability comes precisely from the impact that seeing bodies in state of evolution creates. That evolutive sense that can be associated to elements of a variety, comes together with a variety of states of evolution in the world of organic species. Not only as an individual, but as well as a species. Coincidence between Riemann and Darwin’s discoveries is not only formal, but as well temporary. Darwin observes that some individuals of concrete species present on their bodies some features, typical of other species, which may be interpreted as evolutive failure. But the most peculiar part of what Darwin exposes is that monstrosity can indeed be artificially made for aesthetical purposes, like it happens in certain animals and plants. Well, this is what the Thesis discovers in Sheffield’s project. The union in a single project of two different nature forms, of which none on the parts is a deformation of the other, but they are both irreducible. Once both parts are collated, a new system which adapts well is discovered. It is a system created by Leibniz in the XVII Century, created to distinguish to principles that clear the difference between the equation methods and differential calculus. This principles are the Principle of Position and the Principle of Continuity. This two principles, translated to the spatial analysis field are key for the two parts of the project. On the one hand, the part developing in a lineal axis belongs to the Principle of Position. This means that that there is a global vision of space after which it is decided which operation to follow, which in this case consists of establishing an axis between two singular positions of the university area. The part which is being deformed while it goes is studied as a continuous action of stretching an existing building, the Firth Court, in which there is no previous spatial analysis. The only way to understand and to explain this action is by the Principle of Continuity. So, all in all, the Thesis changes the view of Sheffield from an Art Autre work to a “monstrosity”, without the negative meaning of it, just as a combination of two different nature formations, which, at the same time, justifies its power as iconic image. Finally, I would like to point out that in the Sheffield’s project there is (drawn and also physically) a sculptural head which has the feature of representing both, a man and a woman’s face. All the work of this Thesis leads to explaining the double nature of the project, taking this double expression head as inspiration.

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To study RAG2 gene regulation in vivo, we developed a blastocyst complementation method in which RAG2-deficient embryonic stem cells were transfected with genomic clones containing RAG2 and then assessed for their ability to generate lymphocytes. A RAG2 genomic clone that contained only the RAG2 promoter sequences rescued V(D)J recombination in RAG2-deficient pro-B cell lines, but did not rescue development of RAG2-deficient lymphocytes in vivo. However, inclusion of varying lengths of sequences 5′ of the RAG2 promoter generated constructs capable of rescuing only in vivo B cell development, as well as other constructs that rescued both B and T cell development. In particular, the 2-kb 5′ region starting just upstream of the RAG2 promoter, as well as the region from 2–7 kb 5′, could independently drive B cell development, but not efficient T cell development. Deletion of the 2-kb 5′ region from the murine germ line demonstrated that this region was not required for RAG expression sufficient to generate normal B or T cell numbers, implying redundancy among 5′ elements. We conclude that RAG2 expression in vivo requires elements beyond the core promoter, that such elements contribute to differential regulation in the B vs. T lineages, and that sequences sufficient to direct B cell expression are located in the promoter-proximal 5′ region.

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In the beginning of modern plant biology, plant biologists followed a simple model for their science. This model included important branches of plant biology known then. Of course, plants had to be identified and classified first. Thus, there was much work on taxonomy, genetics, and physiology. Ecology and evolution were approached implicitly, rather than explicitly, through paleobotany, taxonomy, morphology, and historical geography. However, the burgeoning explosion of knowledge and great advances in molecular biology, e.g., to the extent that genes for specific traits can be added (or deleted) at will, have created a revolution in the study of plants. Genomics in agriculture has made it possible to address many important issues in crop production by the identification and manipulation of genes in crop plants. The current model of plant study differs from the previous one in that it places greater emphasis on developmental controls and on evolution by differential fitness. In a rapidly changing environment, the current model also explicitly considers the phenotypic variation among individuals on which selection operates. These are calls for the unity of science. In fact, the proponents of “Complexity Theory” think there are common algorithms describing all levels of organization, from atoms all the way to the structure of the universe, and that when these are discovered, the issue of scaling will be greatly simplified! Plant biology must seriously contribute to, among other things, meeting the nutritional needs of the human population. This challenge constitutes a key part of the backdrop against which future evolution will occur. Genetic engineering technologies are and will continue to be an important component of agriculture; however, we must consider the evolutionary implications of these new technologies. Meeting these demands requires drastic changes in the undergraduate curriculum. Students of biology should be trained in molecular, cellular, organismal, and ecosystem biology, including all living organisms.

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Young, developing fruits of nasturtium (Tropaeolum majus L.) accumulate large deposits of nonfucosylated xyloglucan (XG) in periplasmic spaces of cotyledon cells. This “storage” XG can be fucosylated by a nasturtium transferase in vitro, but this does not happen in vivo, even as a transitory signal for secretion. The only XG that is clearly fucosylated in these fruits is the structural fraction (approximately 1% total) that is bound to cellulose in growing primary walls. The two fucosylated subunits that are formed in vitro are identical to those found in structural XG in vivo. The yield of XG-fucosyltransferase activity from membrane fractions is highest per unit fresh weight in the youngest fruits, especially in dissected cotyledons, but declines when storage XG is forming. A block appears to develop in the secretory machinery of young cotyledon cells between sites that galactosylate and those that fucosylate nascent XG. After extensive galactosylation, XG traffic is diverted to the periplasm without fucosylation. The primary walls buried beneath accretions of storage XG eventually swell and lose cohesion, probably because they continue to extend without incorporating components such as fucosylated XG that are needed to maintain wall integrity.

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Os cursos de graduação em odontologia vêm privilegiando uma formação fundamentada na técnica, com práticas curativistas e individualizadas, tornando-se incapazes de formar a força de trabalho necessária à resolução dos problemas de saúde bucal da população. Com a implementação das Diretrizes Curriculares Nacionais (DCN) para os cursos de graduação em odontologia, uma série de mudanças curriculares vêm sendo executadas no sentido de favorecer a formação adequada. Acredita-se que a educação pela experiência configure-se como um conjunto de ferramentas viável e eficaz para garantir a formação adequada e coerente com os princípios do Sistema Único de Saúde (SUS). Cita-se, como uma dessas possibilidades, os Estágios Curriculares Supervisionados (ECS), previstos nas DCN para serem desenvolvidos de forma articulada e com complexidade crescente ao longo do processo de formação. O estudo destina-se a compreender a articulação ensino-trabalho-cidadania por diferentes olhares e, aliado a experiências vivenciais dessa articulação, construir um modelo de Estágio Curricular Supervisionado (ECS) em serviço público de saúde, no âmbito da Atenção Primária em Saúde (APS), para cursos de graduação em odontologia. Trata-se de um estudo qualitativo dividido em duas fases. Na primeira, foi experienciado um modelo de estágio vinculado à um projeto de pesquisa que se propõe à inovar as práticas de saúde bucal no SUS, utilizando-se de uma proposta de clínica ampliada. Nessa etapa, participaram a pesquisadora, estagiários e preceptores que foram entrevistados e/ou escreveram diários de campo. Na segunda fase, alunos de odontologia, profissionais e gestores de serviços de saúde do município de São Paulo manifestaram suas percepções por meio de grupos focais e entrevistas individuais, respectivamente. O material coletado foi analisado por intermédio da hermenêutica dialética e da triangulação de dados. Os dados descortinam a intimidade das clínicas de uma Faculdade de odontologia, revelando o que se denominou de ensino da odontologia \'in vitro\', distante da realidade e limitado no sentido de solucionar os problemas de saúde bucal do público atendido. Em contrapartida, foi evidente os benefícios que as vivências no mundo real, nos mais variados espaços, podem trazer para esses estudantes. Para os estagiários do modelo experienciado, a prática em clínica ampliada permite extrapolar a odontologia \'in vitro\' e se aproximar da realidade. Preceptores e gestores manifestam opiniões convergentes e explicitam, ainda, o poder transformador que a presença de estudantes denota para os serviços além de induzir à educação permanente dos profissionais que atuam como preceptores. Com bases nessas colocações, foi elaborado um modelo de ECS para cursos de odontologia, de modo a permitir que os estudantes experienciem a realidade de saúde e trabalhem na dimensão da clínica do corpo vivo, subjetivado e complexo. Deseja-se oferecer ao estudante a possibilidade de refletir e experienciar os espaços onde as ações em saúde são produzidas, em um processo de ensino-aprendizagem centrado metodologias ativas, com a mediação pedagógica desenvolvida por preceptores e docentes. Acredita-se que suas características, pensadas em função da triangulação dos diferentes olhares que compuseram o estudo, revertem-se de força suficiente para inquietar o instituído e metamorfosear a formação disfarçada da odontologia.

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The original motivation for this paper was to provide an efficient quantitative analysis of convex infinite (or semi-infinite) inequality systems whose decision variables run over general infinite-dimensional (resp. finite-dimensional) Banach spaces and that are indexed by an arbitrary fixed set J. Parameter perturbations on the right-hand side of the inequalities are required to be merely bounded, and thus the natural parameter space is l ∞(J). Our basic strategy consists of linearizing the parameterized convex system via splitting convex inequalities into linear ones by using the Fenchel–Legendre conjugate. This approach yields that arbitrary bounded right-hand side perturbations of the convex system turn on constant-by-blocks perturbations in the linearized system. Based on advanced variational analysis, we derive a precise formula for computing the exact Lipschitzian bound of the feasible solution map of block-perturbed linear systems, which involves only the system’s data, and then show that this exact bound agrees with the coderivative norm of the aforementioned mapping. In this way we extend to the convex setting the results of Cánovas et al. (SIAM J. Optim. 20, 1504–1526, 2009) developed for arbitrary perturbations with no block structure in the linear framework under the boundedness assumption on the system’s coefficients. The latter boundedness assumption is removed in this paper when the decision space is reflexive. The last section provides the aimed application to the convex case.

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Fluctuations of trace gas activity as a response to variations in weather and microclimate conditions were monitored over a year in a shallow volcanic cave (Painted Cave, Galdar, Canary Islands, Spain). 222Rn concentration was used due to its greater sensitivity to hygrothermal variations than CO2 concentration. Radon concentration in the cave increases as effective vapour condensation within the porous system of the rock surfaces inside the cave increases due to humidity levels of more than 70%. Condensed water content in pores was assessed and linked to a reduction in the direct passage of trace gases. Fluctuations in radon activity as a response to variations in weather and microclimate conditions were statistically identified by clustering entropy changes on the radon signal and parameterised to predict radon concentration anomalies. This raises important implications for other research fields, including the surveillance of shallow volcanic and seismic activity, preventive conservation of cultural heritage in indoor spaces, indoor air quality control and studies to improve understanding of the role of subterranean terrestrial ecosystems as reservoirs and/or temporary sources of trace gases.

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This paper focuses on the cave houses of Crevillente (Spain) as a traditional housing experience which takes advantage of local environmental conditions through simple architectural proposals, paying particular attention to the presence of radon gas inside these underground constructions. Our aim is twofold: first, to analyse the architectural conditions of the different excavated typologies found in the municipality and second, to relate them to the existing radon gas levels after checking internal concentration by means of E-PERM® long-term devices placed inside the cave houses in 2011. The measurements corresponding to the main typologies in normal use conditions show that the highest values are 881.9 Bq/m3 in the cave typology, 484.1 Bq/m3 in the cave + attached constructions typology and 373.4 Bq/m3 in the cave + house typology, with geometric mean values of 572.1, 114.0 and 75.5 Bq/m3, respectively. It can be inferred from these results that cave house levels sometimes exceed those included in the 90/143/Euratom European Commission Recommendation on the protection of the public against indoor exposure to radon. The reason why cave houses are more susceptible to radon accumulation in their spaces lies in their direct and permanent contact with the ground where they are located.