Alcance y límites de la interpretación analógica

Resumen: El objetivo principal de esta investigación es definir cuál es el alcance y cuáles son los límites del uso de la analogía en el Derecho. Para el efecto, se comienza estudiando el concepto, las clases y la justificación de la analogía (capítulos I a III), primero desde un punto de vista netamente teórico y metafísico, y luego con un enfoque práctico jurídico. El capítulo IV revisa qué funciones tiene y para qué no sirve la analogía en el Derecho. A continuación se delimita cuándo es posible acudir al recurso analógico, señalando cuáles son los requisitos necesarios para que la analogía opere (capítulo V) y a qué objetos jurídicos puede aplicarse la analogía (capítulo VI). El capítulo VII estudia la diversa fortaleza intrínseca de los diferentes tipos de analogía que pueden darse en el Derecho. Tomando en cuenta todos estos antecedentes, el capítulo VIII termina definiendo ya concretamente cuáles son los casos en que la analogía en el Derecho (tanto la “analogía legis”, como la “analogía iuris”) es eficaz jurídicamente, y qué motivos podrían hacer que su aplicación resulte impedida o limitada.

Dynamic Fracture Instability Of Tough Bulk Metallic Glass

We report the observations of a clear fractographic evolution from vein pattern, dimple structure, and then to periodic corrugation structure, followed by microbranching pattern, along the crack propagation direction in the dynamic fracture of a tough Zr41.2Ti13.8Cu12.5Ni10Be22.5 (Vit.1) bulk metallic glass (BMGs) under high-velocity plate impact. A model based on fracture surface energy dissipation and void growth is proposed to characterize this fracture pattern transition. We find that once the dynamic crack propagation velocity reaches a critical fraction of Rayleigh wave speed, the crack instability occurs; hence, crack microbranching goes ahead. Furthermore, the correlation between the critical velocity of amorphous materials and their intrinsic strength such as Young's modulus is uncovered. The results may shed new insight into dynamic fracture instability for BMGs. (C) 2008 American Institute of Physics.

eHealth e a adoção da inovação em assisted living technologies : o caso das demências

RESUMO - Assistimos hoje a um contexto marcado (i) pelo progressivo envelhecimento das sociedades ocidentais, (ii) pelo aumento da prevalência das doenças crónicas, de que as demências são um exemplo, (iii) pelo significativo aumento dos custos associados a estas patologias, (iv) por orçamentos públicos fortemente pressionadas pelo controlo da despesa, (v) por uma vida moderna que dificulta o apoio intergeracional, tornando o suporte proporcionado pelos filhos particularmente difícil, (vi) por fortes expectativas relativamente à prestação de cuidados de saúde com qualidade. Teremos assim de ser capazes de conseguir melhorar os serviços de saúde, ao mesmo tempo que recorremos a menos recursos financeiros e humanos, pelo que a inovação parece ser crítica para a sustentabilidade do sistema. Contudo a difusão das Assistive Living Technologies, apesar do seu potencial, tem sido bastante baixa, nomeadamente em Portugal. Porquê? Hamer, Plochg e Moreira (2012), no editorial do International Journal of Healthcare Management, enquadram a Inovação como “podendo ser imprevisível e mesmo dolorosa, pelo que talvez possamos não ficar surpreendidos se surgirem resistências e que, inovações bastante necessárias, capazes de melhorar os indicadores de saúde, tenham sido de adoção lenta ou que tenham mesmo sido insustentáveis”. Em Portugal não há bibliografia que procure caracterizar o modelo de difusão da inovação em eHealth ou das tecnologias de vivência assistida. A bibliografia internacional é igualmente escassa. O presente projeto de investigação, de natureza exploratória, tem como objetivo principal, identificar barreiras e oportunidades para a implementação de tecnologias eHealth, aplicadas ao campo das demências. Como objetivos secundários pretendemse identificar as oportunidades e limitações em Portugal: mapa de competências nacionais, e propor medidas que possa acelerar a inovação em ALT, no contexto nacional. O projeto seguirá o modelo de um estudo qualitativo. Para o efeito foram conduzidas entrevistas em profundidade junto de experts em ALT, procurando obter a visão daqueles que participam do lado da Oferta- a Indústria; do lado da Procura- doentes, cuidadores e profissionais de saúde; bem como dos Reguladores. O instrumento utilizado para a recolha da informação pretendida foi o questionário não estruturado. A análise e interpretação da informação recolhida foram feitas através da técnica de Análise de Conteúdo. Os resultados da Análise de Conteúdo efetuada permitiram expressar a dicotomia barreira/oportunidade, nas seguintes categorias aqui descritas como contextos (i) Contexto Tecnológico, nas subcategorias de Acesso às Infraestruturas; Custo da Tecnologia; Interoperabilidade, (ii) Contexto do Valor Percecionado, nas subcategorias de Utilidade; Eficiência; Divulgação, (iii) Contexto Político, compreendendo a Liderança; Organização; Regulação; Recursos, (iv) Contexto Sociocultural, incluindo nomeadamente Idade; Literacia; Capacidade Económica, (v) Contexto Individual, incluindo como subcategorias, Capacidade de Adaptação a Novas tecnologias; Motivação; Acesso a equipamentos (vi) Contexto Específico da Doença, nomeadamente o Impacto Cognitivo; Tipologia Heterogénea e a Importância do Cuidador. Foi proposto um modelo exploratório, designado de Modelo de Contextos e Forças, que estudos subsequentes poderão validar. Neste modelo o Contexto Tecnológico é um Força Básica ou Fundamental; o Contexto do Valor Percecionado, constitui-se numa Força Crítica para a adoção de inovação, que assenta na sua capacidade para oferecer valor aos diversos stakeholders da cadeia de cuidados. Temos também o Contexto Político, com capacidade de modelar a adoção da inovação e nomeadamente com capacidade para o acelerar, se dele emitir um sinal de urgência para a mudança. O Contexto Sociocultural e Individual expressam uma Força Intrínseca, dado que elas são características internas, próprias e imutáveis no curto-prazo, das sociedade e das pessoas. Por fim há que considerar o Contexto Específico da Doença, nesta caso o das demências. Das conclusões do estudo parece evidente que as condições tecnológicas estão medianamente satisfeitas em Portugal, com evidentes progressos nos últimos anos (exceção para a interoperabilidade aonde há necessidade de maiores progressos), não constituindo portanto barreira à introdução de ALT. Aonde há necessidade de investir é nas áreas do valor percebido. Da análise feita, esta é uma área que constitui uma barreira à introdução e adoção das ALT em Portugal. A falta de perceção do valor que estas tecnologias trazem, por parte dos profissionais de saúde, doentes, cuidadores e decisores políticos, parece ser o principal entrave à sua adoção. São recomendadas estratégias de modelos colaborativos de Investigação e Desenvolvimento e de abordagens de cocriação com a contribuição de todos os intervenientes na cadeia de cuidados. Há também um papel que cabe ao estado no âmbito das prioridades e da mobilização de recursos, sendo-lhe requerida a expressão do sentido de urgência para que esta mudança aconteça. Foram também identificadas oportunidades em diversas áreas, como na prevenção, no diagnóstico, na compliance medicamentosa, na terapêutica, na monitorização, no apoio à vida diária e na integração social. O que é necessário é que as soluções encontradas constituam respostas àquilo que são as verdadeiras necessidades dos intervenientes e não uma imposição tecnológica que só por si nada resolve. Do estudo resultou também a perceção de que há que (i) continuar a trabalhar no sentido de aproximar a comunidade científica, da clínica e do doente, (ii) fomentar a colaboração entre centros, com vista à criação de escala a nível global. Essa colaboração já parece acontecer a nível empresarial, tendo sido identificadas empresas Portuguesas com vocação global. A qualidade individual das instituições de ensino, dos centros de investigação, das empresas, permite criar as condições para que Portugal possa ser país um piloto e um case-study internacional em ALT, desde que para tal pudéssemos contar com um trabalho colaborativo entre instituições e com decisões políticas arrojadas.

Fiber bragg gratings:advances in fabrication process and tools

Successful commercialization of a technology such as Fiber Bragg Gratings requires the ability to manufacture devices repeatably, quickly and at low cost. Although the first report of photorefractive gratings was in 1978 it was not until 1993, when phase mask fabrication was demonstrated, that this became feasible. More recently, draw tower fabrication on a production level and grating writing through the polymer jacket have been realized; both important developments since they preserve the intrinsic strength of the fiber. Potentially the most significant recent development has been femtosecond laser inscription of gratings. Although not yet a commercial technology, it provides the means of writing multiple gratings in the optical core providing directional sensing capability in a single fiber. Femtosecond processing can also be used to machine the fiber to produce micronscale slots and holes enhancing the interaction between the light in the core and the surrounding medium. © 2011 Bentham Science Publishers Ltd. All rights reserved.

Fiber bragg gratings:advances in fabrication process and tools

Successful commercialization of a technology such as Fiber Bragg Gratings requires the ability to manufacture devices repeatably, quickly and at low cost. Although the first report of photorefractive gratings was in 1978 it was not until 1993, when phase mask fabrication was demonstrated, that this became feasible. More recently, draw tower fabrication on a production level and grating writing through the polymer jacket have been realized; both important developments since they preserve the intrinsic strength of the fiber. Potentially the most significant recent development has been femtosecond laser inscription of gratings. Although not yet a commercial technology, it provides the means of writing multiple gratings in the optical core providing directional sensing capability in a single fiber. Femtosecond processing can also be used to machine the fiber to produce micronscale slots and holes enhancing the interaction between the light in the core and the surrounding medium. © 2011 Bentham Science Publishers Ltd. All rights reserved.

Atomically thin boron nitride: unique properties and applications

Atomically thin boron nitride (BN) is an important 2D nanomaterial, with many properties distinct from graphene. In this feature article, these unique properties and associated applications, often not feasible with graphene, are outlined. The article starts with characterization and identification of atomically thin BN. It is followed by demonstrating their strong oxidation resistance at high temperatures and applications in protecting metals from oxidation and corrosion. As flat insulators, BN nanosheets are ideal dielectric substrates for surface enhanced Raman spectroscopy (SERS) and electronic devices based on 2D heterostructures. The light emission of BN nanosheets in the deep ultraviolet (DUV) and ultraviolet (UV) regions is also included for its scientific and technological importance. The last part is dedicated to synthesis, characterization, and optical properties of BN nanoribbons, a special form of nanosheets.

Influence of Different Surface Treatments on Bond Strength of Resin Composite Using the Intrinsic Characterization Technique

Objective: This study evaluated the influence of different surface treatments on the resin bond strength/light-cured characterizing materials (LCCMs), using the intrinsic characterization technique. The intrinsic technique is characterized by the use of LCCMs between the increments of resin composite (resin/thin film of LCCM/external layer of resin covering the LCCM).Materials and Methods: Using a silicone matrix, 240 blocks of composite (Z350/3M ESPE) were fabricated. The surfaces received different surface treatments, totaling four groups (n=60): Group C (control group), no surface treatment was used; Group PA, 37% phosphoric acid for one minute and washing the surface for two minutes; Group RD, roughening with diamond tip; and Group AO, aluminum oxide. Each group was divided into four subgroups (n=15), according to the LCCMs used: Subgroup WT, White Tetric Color pigment (Ivoclar/Vivadent) LCCM; Subgroup BT, Black Tetric Color pigment (Ivoclar/Vivadent) LCCM; Subgroup WK, White Kolor Plus pigment (Kerr) LCCM; Subgroup BK, Brown Kolor Plus pigment (Kerr) LCCM. All materials were used according to the manufacturer's instructions. After this, block composites were fabricated over the LCCMs. Specimens were sectioned and submitted to microtensile testing to evaluate the bond strength at the interface. Data were submitted to two-way analysis of variance (ANOVA) (surface treatment and LCCMs) and Tukey tests.Results: ANOVA presented a value of p<0.05. The mean values (+/- SD) for the factor surface treatment were as follows: Group C, 30.05 MPa (+/- 5.88)a; Group PA, 23.46 MPa (+/- 5.45)b; Group RD, 21.39 MPa (+/- 6.36)b; Group AO, 15.05 MPa (+/- 4.57)c. Groups followed by the same letters do not present significant statistical differences. The control group presented significantly higher bond strength values than the other groups. The group that received surface treatment with aluminum oxide presented significantly lower bond strength values than the other groups.Conclusion: Surface treatments of composite with phosphoric acid, diamond tip, and aluminum oxide significantly diminished the bond strength between composite and the LCCMs.

Knee extensor strength differences in obese and healthy-weight 10-13 year olds

The purpose of this study was to investigate if obese children have reduced knee extensor (KE) strength and to explore the relationship between adiposity and KE strength. An observational case-control study was conducted in three Australian states, recruiting obese [n=107 (51 female, 56 male)] and healthy-weight [n=132 (56 female, 76 male)] 10–13 year old children. Body mass index, body composition (dual energy X-ray absorptiometry), isokinetic/isometric peak KE torques (dynamometry) and physical activity (accelerometry) were assessed. Results revealed that compared with their healthy-weight peers, obese children had higher absolute KE torques (P≤0.005), equivocal KE torques when allometrically normalized for fat-free mass (FFM) (P≥0.448) but lower relative KE torques when allometrically normalized for body mass (P≤0.008). Adjustments for maternal education, income and accelerometry had little impact on group differences, except for isometric KE torques relative to body mass which were no longer significantly lower in obese children (P≥0.013, not significant after controlling for multiple comparisons). Percent body fat was inversely related to KE torques relative to body mass (r= -0.22 to -0.35, P≤0.002), irrespective of maternal education, income or accelerometry. In conclusion, while obese children have higher absolute KE strength and FFM, they have less functional KE strength (relative to mass) available for weight-bearing activities than healthy-weight children. The finding that FFM-normalized KE torques did not differ suggests that the intrinsic contractile properties of the KE muscles are unaffected by obesity. Future research is needed to see if deficits in KE strength relative to mass translate into functional limitations in weight-bearing activities.

Micromechanics Of Fatigue Crack-Growth At Low Stress Intensities In A High-Strength Steel

An attempt to systematically investigate the effects of microstructural parameters in influencing the resistance to fatigue crack growth (FCG) in the near-threshold region under three different temper levels has been made for a high strength low alloy steel to observe in general, widely different trends in the dependence of both the total threshold stress intensity range, DELTA-K(th) and the intrinsic or effective threshold stress intensity range, DELTA-K(eff-th) on the prior austenitic grain size (PAGS). While a low strain hardening microstructure obtained by tempering at high temperatures exhibited strong dependence of DELTA-K(th) on the PAGS by virtue of strong interactions of crack tip slip with the grain boundary, a high strength, high strain hardening microstructure as a result of tempering at low temperature exhibited a weak dependence. The lack of a systematic variation of the near-threshold parameters with respect to grain size in temper embrittled structures appears to be related to the wide variations in the amount of intergranular fracture near threshold. Crack closure, to some extent provides a basis on which the increases in DELTA-K(th) at larger grain sizes can be rationalised. This study, in addition, provides a wide perspective on the relative roles of slip behaviour embrittlement and environment that result in the different trends observed in the grain size dependence of near-threshold fatigue parameters, based on which the inconsistency in the results reported in the literature can be clearly understood. Assessment of fracture modes through extensive fractography revealed that prior austenitic grain boundaries are effective barriers to cyclic crack growth compared to martensitic packet boundaries, especially at low stress intensities. Fracture morphologies comprising of low energy flat transgranular fracture can occur close to threshold depending on the combinations of strain hardening behaviour, yield strength and embrittlement effects. A detailed consideration is given to the discussion of cyclic stress strain behaviour, embrittlement and environmental effects and the implications of these phenomena on the crack growth behaviour near threshold.

Activation of InsP(3) receptors is sufficient for inducing graded intrinsic plasticity in rat hippocampal pyramidal neurons

The synaptic plasticity literature has focused on establishing necessity and sufficiency as two essential and distinct features in causally relating a signaling molecule to plasticity induction, an approach that has been surprisingly lacking in the intrinsic plasticity literature. In this study, we complemented the recently established necessity of inositol trisphosphate (InsP(3)) receptors (InsP(3)R) in a form of intrinsic plasticity by asking if InsP(3)R activation was sufficient to induce intrinsic plasticity in hippocampal neurons. Specifically, incorporation of D-myo-InsP(3) in the recording pipette reduced input resistance, maximal impedance amplitude, and temporal summation but increased resonance frequency, resonance strength, sag ratio, and impedance phase lead. Strikingly, the magnitude of plasticity in all these measurements was dependent on InsP 3 concentration, emphasizing the graded dependence of such plasticity on InsP(3)R activation. Mechanistically, we found that this InsP(3)-induced plasticity depended on hyperpolarization-activated cyclic nucleotide-gated channels. Moreover, this calcium-dependent form of plasticity was critically reliant on the release of calcium through InsP(3)Rs, the influx of calcium through N-methyl-D-aspartate receptors and voltage-gated calcium channels, and on the protein kinase A pathway. Our results delineate a causal role for InsP(3)Rs in graded adaptation of neuronal response dynamics, revealing novel regulatory roles for the endoplasmic reticulum in neural coding and homeostasis.

Measurement Of Fracture Toughness And Interfacial Shear Strength Of Hard And Brittle Cr Coating On Ductile Steel Substrate

The fracture toughness and interfacial adhesion properties of a coating on its substrate are considered to be crucial intrinsic parameters determining performance and reliability of coating-substrate system. In this work, the fracture toughness and interfacial shear strength of a hard and brittle Cr coating on a normal medium carbon steel substrate were investigated by means of a tensile test. The normal medium carbon steel substrate electroplated with a hard and brittle Cr coating was quasi-statically stretched to induce an array of parallel cracks in the coating. An optical microscope was used to observe the cracking of the coating and the interfacial decohesion between the coating and the substrate during the loading. It was found that the cracking of the coating initiated at critical strain, and then the number of the cracks of the coating per unit axial distance increased with the increase in the tensile strain. At another critical strain, the number of the cracks of the coating became saturated, i.e. the number of cracks per unit axial distance became a constant after this critical strain. Based on the experiment result, the fracture toughness of the brittle coating can be determined using a mechanical model. Interestingly, even when the whole specimen fractured completely under an extreme strain of the substrate, the interfacial decohesion or buckling of the coating on its substrate was completely absent. The test result is different from that appeared in the literature though the identical test method and the brittle coating/ductile metal substrate system are taken. It was found that this difference can be attributed to an important mechanism that the Cr coating on the steel substrate has a good adhesion, and the ultimate interfacial shear strength between the Cr coating and the steel substrate has exceeded the maximum shear flow strength level of the steel substrate. This result also indicates that the maximum shear flow strength level of the ductile steel substrate can be only taken as a lower bound estimate on the ultimate shear strength of the interface. This estimation of the ultimate interfacial shear strength is consistent with the theoretical analysis and prediction presented in the literature.

Direct detection of the relative strength of Rashba and Dresselhaus spin-orbit interaction: Utilizing the SU(2) symmetry

We propose a simple method to detect the relative strength of Rashba and Dresselhaus spin-orbit interactions in quantum wells (QWs) without relying on the directional-dependent physical quantities. This method utilizes the two different critical gate voltages that leading to the remarkable signals of SU(2) symmetry, which happens to reflect the intrinsic-structure-inversion asymmetry of the QW. We support our proposal by the numerical calculation of in-plane relaxation times based on the self-consistent eight-band Kane model. We find that the two different critical gate voltages leading to the maximum spin-relaxation times [one effect of the SU(2) symmetry] can simply determine the ratio of the coefficients of Rashba and Dresselhaus terms. Our proposal can also be generalized to extract the relative strengths of the spin-orbit interactions in quantum-wire and quantum-dot structures.

Intersubject Regularity in the Intrinsic Shape of Human V1

Previous studies have reported considerable intersubject variability in the three-dimensional geometry of the human primary visual cortex (V1). Here we demonstrate that much of this variability is due to extrinsic geometric features of the cortical folds, and that the intrinsic shape of V1 is similar across individuals. V1 was imaged in ten ex vivo human hemispheres using high-resolution (200 μm) structural magnetic resonance imaging at high field strength (7 T). Manual tracings of the stria of Gennari were used to construct a surface representation, which was computationally flattened into the plane with minimal metric distortion. The instrinsic shape of V1 was determined from the boundary of the planar representation of the stria. An ellipse provided a simple parametric shape model that was a good approximation to the boundary of flattened V1. The aspect ration of the best-fitting ellipse was found to be consistent across subject, with a mean of 1.85 and standard deviation of 0.12. Optimal rigid alignment of size-normalized V1 produced greater overlap than that achieved by previous studies using different registration methods. A shape analysis of published macaque data indicated that the intrinsic shape of macaque V1 is also stereotyped, and similar to the human V1 shape. Previoud measurements of the functional boundary of V1 in human and macaque are in close agreement with these results.