990 resultados para théorème de Roth


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Given the ubiquity of the parasites and their important fitness consequences on mate and offspring condition, selection for the ability to distinguish healthy from parasitized potential mates is a key process to enhance Darwinian fitness. In this study, we experimentally evaluated how the immunological experience of two potential partners influences mate choice, using the sex-role-reversed pipefish Syngnathus typhle. We exposed S. typhle to immune challenges with heat-killed Vibrio bacteria and investigated whether the activation of the immune system determined mate preferences. Our results demonstrate that the immune status of the potential partners influenced female mate preference, such that females that were exposed to an immune challenge became choosy and favored unchallenged males. Males, however, did not show any preferences for female immune status. In this context, we discuss mate choice decisions and behavioral plasticity as a complex result of immune challenge, severity of infection, as well as trans-generational effects.

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A connectivity function defined by the 3D-Euler number, is a topological indicator and can be related to hydraulic properties (Vogel and Roth, 2001). This study aims to develop connectivity Euler indexes as indicators of the ability of soils for fluid percolation. The starting point was a 3D grey image acquired by X-ray computed tomography of a soil at bulk density of 1.2 mg cm-3. This image was used in the simulation of 40000 particles following a directed random walk algorithms with 7 binarization thresholds. These data consisted of 7 files containing the simulated end points of the 40000 random walks, obtained in Ruiz-Ramos et al. (2010). MATLAB software was used for computing the frequency matrix of the number of particles arriving at every end point of the random walks and their 3D representation.

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Neutrophil gelatinase associated lipocalin (NGAL) protein is attracting a great interest because of its antibacterial properties played upon modulating iron content in competition against iron acquisition processes developed by pathogenic bacteria that bind selective ferric iron chelators (siderophores). Besides its known high affinity to enterobactin, the most important siderophore, it has been recently shown that NGAL is able to bind Fe(III) coordinated by catechols. The selective binding of Fe(III)-catechol ligands to NGAL is here studied by using iron coordination structures with one, two, and three catecholate ligands. By means of a computational approach that consists of B3LYP/6-311G(d,p) quantum calculations for geometries, electron properties and electrostatic potentials of ligands, protein–ligand flexible docking calculations, analyses of protein–ligand interfaces, and Poisson–Boltzmann electrostatic potentials for proteins, we study the binding of iron catecholate ligands to NGAL as a central member of the lipocalin family of proteins. This approach provides a modeling basis for exploring in silico the selective binding of iron catecholates ligands giving a detailed picture of their interactions in terms of electrostatic effects and a network of hydrogen bonds in the protein binding pocket.

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Cinnamaldehyde (CA) has been reported to have antiinflammatory, anti-bacterial, anti-fungal, chemoprotective and anti-carcinogenic activity. Here, we further investigated the immune-modulating capacity of CA.

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We are witnessing a fundamental transformation in how Internet of Things (IoT) is having an impact on the experience users have with data-driven devices, smart appliances, and connected products. The experience of any place is commonly defined as the result of a series of user engagements with a surrounding place in order to carry out daily activities (Golledge, 2002). Knowing about users? experiences becomes vital to the process of designing a map. In the near future, a user will be able to interact directly with any IoT device placed in his surrounding place and very little is known on what kinds of interactions and experiences a map might offer (Roth, 2015). The main challenge is to develop an experience design process to devise maps capable of supporting different user experience dimensions such as cognitive, sensory-physical, affective, and social (Tussyadiah and Zach, 2012). For example, in a smart city of the future, the IoT devices allowing a multimodal interaction with a map could help tourists in the assimilation of their knowledge about points of interest (cognitive experience), their association of sounds and smells to these places (sensory-physical experience), their emotional connection to them (affective experience) and their relationships with other nearby tourists (social experience). This paper aims to describe a conceptual framework for developing a Mapping Experience Design (MXD) process for building maps for smart connected places of the future. Our MXD process is focussed on the cognitive dimension of an experience in which a person perceives a place as a "living entity" that uses and feeds through his experiences. We want to help people to undergo a meaningful experience of a place through mapping what is being communicated during their interactions with the IoT devices situated in this place. Our purpose is to understand how maps can support a person?s experience in making better decisions in real-time.

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Antecedentes: El potencial alergénico de las proteínas puede alterarse mediante modificaciones fisicoquímicas. El glutatión (GSH) es un agente reductor utilizado como antioxidante en productos alimentarios. Objetivo: Este estudio pretende caracterizar el plegamiento natural de las proteínas de melocotón y cuantificar la alergenicidad del alérgeno mayor del melocotón, Pru p 3, natural y reducido. Métodos: Para ello, se purificó Pru p 3 y se analizó su conformación mediante dicroismo circular (DC). Mediante el análisis con tiol fluorescente, se detectaron las proteínas reducidas en melocotones frescos. Pru p 3 reducido por GSH fue analizado mediante un ensayo in vitro de proliferación de células T e in vivo mediante prueba cutánea. Resultados: Pru p 3 reducido produjo reacciones variables en las pruebas cutáneas de los pacientes alérgicos a melocotón; sin embargo, su estabilidad a la digestión gastrointestinal fue similar a la de la forma natural. La respuesta proliferativa de las células mononucleares de los pacientes alérgicos frente a Pru p 3 reducido mostró una tendencia a ser inferior, mientras que la secreción de citocinas IFN?, IL5 e IL10 fue similar a la producida con la forma natural. La reducción alteró la unión de la IgE a Pru p 3 en un pool de sueros de pacientes alérgicos a melocotón. Conclusin: En conclusión, el glutatión es capaz de reducir Pru p 3, al menos de forma transitoria. En nuestro estudio, la reducción no afectó a la alergenicidad de Pru p 3, de forma que dicho aditivo no parece resolver el riesgo de alergia en pacientes alérgicos a melocotón. Palabras clave: GSH. Pru p 3. Alergia a melocotón. Agente reductor. Unión a IgE.

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We conclude that Bet v 1 and Bos d 5 not only structurally mimic human LCN2, but also functionally by their ability to bind iron via siderophores. The apo-forms promote Th2 cells, whereas the holo-forms appear to be immunosuppressive. These results provide for the first time a functional understanding on the principle of allergenicity of major allergens from entirely independent sources, like birch and milk.

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O objetivo deste estudo foi comparar as angulações e torques de braquetes de marcas comerciais distintas em relação à prescrição de Roth e também em relação aos valores preconizados pelo fabricante. Foram utilizados 150 braquetes metálicos de aço inoxidável, de caninos e incisivos superiores na respectiva prescrição, avaliadas por meio de um perfilômetro. Após a coleta dos dados e aplicação do tratamento estatístico, os resultados demonstraram que os valores de torque obtidos com a prescrição de Roth foram semelhantes entre os fabricantes. Na angulação, os caninos superiores apresentaram valores acima do proposto pelo autor para o fabricante Morelli, e para os dentes 21 e 22, a angulação foi maior para o fabricante Abzil. Na comparação dos valores de torque obtidos com os valores recomendados pelos fabricantes, a Unitek demonstrou maior fidedignidade no torque comparada às demais marcas. Conclui-se que as diferenças tanto de torque quanto de angulação quando comparados aos valores do autor e à prescrição dos fabricantes, se enquadram dentro de um grau de tolerância preconizada por um órgão regulador de peças ortodônticas alemãs.