989 resultados para brake even point


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Let (M, g) be a complete Riemannian manifold, Omega subset of Man open subset whose closure is homeomorphic to an annulus. We prove that if a,Omega is smooth and it satisfies a strong concavity assumption, then there are at least two distinct geodesics in starting orthogonally to one connected component of a,Omega and arriving orthogonally onto the other one. Using the results given in Giamb et al. (Adv Differ Equ 10:931-960, 2005), we then obtain a proof of the existence of two distinct homoclinic orbits for an autonomous Lagrangian system emanating from a nondegenerate maximum point of the potential energy, and a proof of the existence of two distinct brake orbits for a class of Hamiltonian systems. Under a further symmetry assumption, the result is improved by showing the existence of at least dim(M) pairs of geometrically distinct geodesics as above, brake orbits and homoclinic orbits. In our proof we shall use recent deformation results proved in Giamb et al. (Nonlinear Anal Ser A: Theory Methods Appl 73:290-337, 2010).

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Let (M, g) be a complete Riemannian Manifold, Omega subset of M an open subset whose closure is diffeomorphic to an annulus. If partial derivative Omega is smooth and it satisfies a strong concavity assumption, then it is possible to prove that there are at least two geometrically distinct geodesics in (Omega) over bar = Omega boolean OR partial derivative Omega starting orthogonally to one connected component of partial derivative Omega and arriving orthogonally onto the other one. The results given in [6] allow to obtain a proof of the existence of two distinct homoclinic orbits for an autonomous Lagrangian system emanating from a nondegenerate maximum point of the potential energy, and a proof of the existence of two distinct brake orbits for a. class of Hamiltonian systems. Under a further symmetry assumption, it is possible to show the existence of at least dim(M) pairs of geometrically distinct geodesics as above, brake orbits and homoclinics.

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We report a novel method for calculating flash points of acyclic alkanes from flash point numbers, N(FP), which can be calculated from experimental or calculated boiling point numbers (Y(BP)) with the equation N(FP) = 1.020Y(BP) - 1.083 Flash points (FP) are then determined from the relationship FP(K) = 23.369N(FP)(2/3) + 20.010N(FP)(1/3) + 31.901 For it data set of 102 linear and branched alkanes, the correlation of literature and predicted flash points has R(2) = 0.985 and an average absolute deviation of 3.38 K. N(FP) values can also be estimated directly from molecular structure to produce an even closer correspondence of literature and predicted FP values. Furthermore, N(FP) values provide a new method to evaluate the reliability of literature flash point data.

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Solar-aided power generation (SAPG) is capable of integrating solar thermal energy into a conventional thermal power plant, at multi-points and multi-levels, to replace parts of steam extractions in the regenerative Rankine cycle. The integration assists the power plant to reduce coal (gas) consumption and pollution emission or to increase power output. The overall efficiencies of the SAPG plants with different solar replacements of extraction steam have been studied in this paper. The results indicate that the solar thermal to electricity conversion efficiencies of the SAPG system are higher than those of a solar-alone power plant with the same temperature level of solar input. The efficiency with solar input at 330 °C can be as high as 45% theoretically in a SAPG plant. Even the low-temperature solar heat at about 85 °C can be used in the SAPG system to heat the lower temperature feedwater, and the solar to electricity efficiency is nearly 10%. However, the low-temperature heat resource is very hard to be used for power generation in other types of solar power plants. Therefore, the SAPG plant is one of the most efficient ways for solar thermal power generation.

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Objective

This study aimed to identify cultural-level variables that may influence the extent to which adolescents from different cultural groups are dissatisfied with their bodies.

Design.
A sample of 1730 male and 2000 female adolescents from Australia, Fiji, Malaysia, Tonga, Tongans in New Zealand, China, Chile, and Greece completed measures of body satisfaction, and the sociocultural influences on body image and body change questionnaire, and self-reported height and weight. Country gross domestic product and national obesity were recorded using global databases.

Results.
Prevalence of obesity/overweight and cultural endorsement of appearance standards explained variance in individual-level body dissatisfaction (BD) scores, even after controlling for the influence of individual differences in body mass index and internalization of appearance standards.

Conclusions.
Cultural-level variables may account for the development of adolescent BD.

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 Partial shading is one of the unavoidable complications in the field of solar power generation. Although the most common approach in increasing a photovoltaic (PV) array’s efficiency has always been to introduce a bypass diode to the said array, this poses another problem in the form of multi-peaks curves whenever the modules are partially shaded. To further complicate matters, most conventional Maximum Power Point Tracking methods develop errors under certain circumstances (for example, they detect the local Maximum Power Point (MPP) instead of the global MPP) and reduce the efficiency of PV systems even further. Presently, much research has been undertaken to improve upon them. This study aims to employ an evolutionary algorithm technique, also known as particle swarm optimization, in MPP detection. VC 2014 Author(s).

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Griffiths proposed a pair of boundary conditions that define a point interaction in one dimensional quantum mechanics. The conditions involve the nth derivative of the wave function where n is a non-negative integer. We re-examine the interaction so defined and explicitly confirm that it is self-adjoint for any even value of n and for n = 1. The interaction is not self-adjoint for odd n > 1. We then propose a similar but different pair of boundary conditions with the nth derivative of the wave function such that the ensuing point interaction is self-adjoint for any value of n.

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[EN] As is well known, in any infinite-dimensional Banach space one may find fixed point free self-maps of the unit ball, retractions of the unit ball onto its boundary, contractions of the unit sphere, and nonzero maps without positive eigenvalues and normalized eigenvectors. In this paper, we give upper and lower estimates, or even explicit formulas, for the minimal Lipschitz constant and measure of noncompactness of such maps.

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We report on a family with a 12-year-old boy who suffered from a maternally inherited syndrome characterized by a combination of sensorineural hearing loss, myoclonus epilepsy, ataxia, severe psychomotor retardation, short stature, and diabetes mellitus. First, he showed a muscular hypotonia with hearing loss; later, he developed a myoclonus epilepsy, growth failure, and severe psychomotor retardation. At the age of 10 years, he developed diabetes mellitus. After initiation of combined ubiquinone and vitamin C treatment, we observed a progression in psychomotor development. Lactate and pyruvate levels in blood and cerebrospinal fluid were normal. No ragged red fibers or ultrastructural abnormalities were seen in a skeletal muscle biopsy. Biochemical assays of respiratory chain complex activities revealed decreased activity of complexes I and IV. By sequence analysis of mitochondrial DNA encoding transfer ribonucleic acids (RNAs), a homoplasmic T to C substitution at nucleotide position 7512 was found affecting a highly conserved base pair in the tRNA(ser(UCN)) acceptor stem. Asymptomatic family members of the maternal line were heteroplasmic for the mutation in blood samples. Analysis of mitochondrial DNA in patients with hearing loss and myoclonus epilepsy is recommended, even in the absence of laboratory findings. Therapeutically, ubiquinone and antioxidants can be beneficial.

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For countless communities around the world, acquiring access to safe drinking water is a daily challenge which many organizations endeavor to meet. The villages in the interior of Suriname have been the focus of many improved drinking water projects as most communities are without year-round access. Unfortunately, as many as 75% of the systems in Suriname fail within several years of implementation. These communities, scattered along the rivers and throughout the jungle, lack many of the resources required to sustain a centralized water treatment system. However, the centralized system in the village of Bendekonde on the Upper Suriname River has been operational for over 10 years and is often touted by other communities. The Bendekonde system is praised even though the technology does not differ significantly from other failed systems. Many of the water systems that fail in the interior fail due to a lack of resources available to the community to maintain the system. Typically, the more complex a system becomes, so does the demand for additional resources. Alternatives to centralized systems include technologies such as point-of-use water filters, which can greatly reduce the necessity for outside resources. In particular, ceramic point-of-use water filters offer a technology that can be reasonably managed in a low resource setting such as that in the interior of Suriname. This report investigates the appropriateness and effectiveness of ceramic filters constructed with local Suriname clay and compares the treatment effectiveness to that of the Bendekonde system. Results of this study showed that functional filters could be produced from Surinamese clay and that they were more effective, in a controlled laboratory setting, than the field performance of the Bendekonde system for removing total coliform. However, the Bendekonde system was more successful at removing E. coli. In a life-cycle assessment, ceramic water filters manufactured in Suriname and used in homes for a lifespan of 2 years were shown to have lower cumulative energy demand, as well as lower global warming potential than a centralized system similar to that used in Bendekonde.

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BACKGROUND Implementation of user-friendly, real-time, electronic medical records for patient management may lead to improved adherence to clinical guidelines and improved quality of patient care. We detail the systematic, iterative process that implementation partners, Lighthouse clinic and Baobab Health Trust, employed to develop and implement a point-of-care electronic medical records system in an integrated, public clinic in Malawi that serves HIV-infected and tuberculosis (TB) patients. METHODS Baobab Health Trust, the system developers, conducted a series of technical and clinical meetings with Lighthouse and Ministry of Health to determine specifications. Multiple pre-testing sessions assessed patient flow, question clarity, information sequencing, and verified compliance to national guidelines. Final components of the TB/HIV electronic medical records system include: patient demographics; anthropometric measurements; laboratory samples and results; HIV testing; WHO clinical staging; TB diagnosis; family planning; clinical review; and drug dispensing. RESULTS Our experience suggests that an electronic medical records system can improve patient management, enhance integration of TB/HIV services, and improve provider decision-making. However, despite sufficient funding and motivation, several challenges delayed system launch including: expansion of system components to include of HIV testing and counseling services; changes in the national antiretroviral treatment guidelines that required system revision; and low confidence to use the system among new healthcare workers. To ensure a more robust and agile system that met all stakeholder and user needs, our electronic medical records launch was delayed more than a year. Open communication with stakeholders, careful consideration of ongoing provider input, and a well-functioning, backup, paper-based TB registry helped ensure successful implementation and sustainability of the system. Additional, on-site, technical support provided reassurance and swift problem-solving during the extended launch period. CONCLUSION Even when system users are closely involved in the design and development of an electronic medical record system, it is critical to allow sufficient time for software development, solicitation of detailed feedback from both users and stakeholders, and iterative system revisions to successfully transition from paper to point-of-care electronic medical records. For those in low-resource settings, electronic medical records for integrated care is a possible and positive innovation.

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La innovación en Sistemas Intesivos en Software está alcanzando relevancia por múltiples razones: el software está presente en sectores como automóvil, teléfonos móviles o salud. Las empresas necesitan conocer aquellos factores que afectan a la innovación para incrementar las probabilidades de éxito en el desarrollo de sus productos y, la evaluación de productos sofware es un mecanismo potente para capturar este conocimiento. En consecuencia, las empresas necesitan evaluar sus productos desde la perpectiva de innovación para reducir la distancia entre los productos desarrollados y el mercado. Esto es incluso más relevante en el caso de los productos intensivos en software, donde el tiempo real, la oportunidad, complejidad, interoperabilidad, capacidad de respuesta y compartción de recursos son características críticas de los nuevos sistemas. La evaluación de la innovación de productos ya ha sido estudiada y se han definido algunos esquemas de evaluación pero no son específicos para Sistemas intensivos en Sofwtare; además, no se ha alcanzado consenso en los factores ni el procedimiento de evaluación. Por lo tanto, tiene sentido trabajar en la definición de un marco de evaluación de innovación enfocado a Sistemas intesivos en Software. Esta tesis identifica los elementos necesarios para construir in marco para la evaluación de de Sistemas intensivos en Software desde el punto de vista de la innovación. Se han identificado dos componentes como partes del marco de evaluación: un modelo de referencia y una herramienta adaptativa y personalizable para la realización de la evaluación y posicionamiento de la innovación. El modelo de referencia está compuesto por cuatro elementos principales que caracterizan la evaluación de innovación de productos: los conceptos, modelos de innovación, cuestionarios de evaluación y la evaluación de productos. El modelo de referencia aporta las bases para definir instancias de los modelos de evaluación de innovación de productos que pueden se evaluados y posicionados en la herramienta a través de cuestionarios y que de forma automatizada aporta los resultados de la evaluación y el posicionamiento respecto a la innovación de producto. El modelo de referencia ha sido rigurosamente construido aplicando modelado conceptual e integración de vistas junto con la aplicación de métodos cualitativos de investigación. La herramienta ha sido utilizada para evaluar productos como Skype a través de la instanciación del modelo de referencia. ABSTRACT Innovation in Software intensive Systems is becoming relevant for several reasons: software is present embedded in many sectors like automotive, robotics, mobile phones or heath care. Firms need to have knowledge about factors affecting the innovation to increase the probability of success in their product development and the assessment of innovation in software products is a powerful mechanism to capture this knowledge. Therefore, companies need to assess products from an innovation perspective to reduce the gap between their developed products and the market. This is even more relevant in the case of SiSs, where real time, timeliness, complexity, interoperability, reactivity, and resource sharing are critical features of a new system. Many authors have analysed product innovation assessment and some schemas have been developed but they are not specific to SiSs; in addition, there is no consensus about the factors or the procedures for performing an assessment. Therefore, it has sense to work in the definition of a customized software product innovation evaluation framework. This thesis identifies the elements needed to build a framework to assess software products from the innovation perspective. Two components have been identified as part of the framework to assess Software intensive Systems from the innovation perspective: a reference-model and an adaptive and customizable tool to perform the assessment and to position product innovation. The reference-model is composed by four main elements characterizing product innovation assessment: concepts, innovation models, assessment questionnaires and product assessment. The reference model provides the umbrella to define instances of product innovation assessment models that can be assessed and positioned through questionnaires in the proposed tool that also provides automation in the assessment and positioning of innovation. The reference-model has been rigorously built by applying conceptual modelling and view integration integrated with qualitative research methods. The tool has been used to assess products like Skype through models instantiated from the reference-model.

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Suppression of cardiac voltage-gated Na+ currents is probably one of the important factors for the cardioprotective effects of the n-3 polyunsaturated fatty acids (PUFAs) against lethal arrhythmias. The α subunit of the human cardiac Na+ channel (hH1α) and its mutants were expressed in human embryonic kidney (HEK293t) cells. The effects of single amino acid point mutations on fatty acid-induced inhibition of the hH1α Na+ current (INa) were assessed. Eicosapentaenoic acid (EPA, C20:5n-3) significantly reduced INa in HEK293t cells expressing the wild type, Y1767K, and F1760K of hH1α Na+ channels. The inhibition was voltage and concentration-dependent with a significant hyperpolarizing shift of the steady state of INa. In contrast, the mutant N406K was significantly less sensitive to the inhibitory effect of EPA. The values of the shift at 1, 5, and 10 μM EPA were significantly smaller for N406K than for the wild type. Coexpression of the β1 subunit and N406K further decreased the inhibitory effects of EPA on INa in HEK293t cells. In addition, EPA produced a smaller hyperpolarizing shift of the V1/2 of the steady-state inactivation in HEK293t cells coexpressing the β1 subunit and N406K. These results demonstrate that substitution of asparagine with lysine at the site of 406 in the domain-1-segment-6 region (D1-S6) significantly decreased the inhibitory effect of PUFAs on INa, and coexpression with β1 decreased this effect even more. Therefore, asparagine at the 406 site in hH1α may be important for the inhibition by the PUFAs of cardiac voltage-gated Na+ currents, which play a significant role in the antiarrhythmic actions of PUFAs.