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Mediante el presente artículo se analiza el fenómeno de los homicidios de líderes sociales y defensores de Derechos Humanos en Colombia a partir del contraste entre el manejo de las cifras de por parte de las entidades estatales y las ONG´s, tanto nacionales como internacionales, con el fin de entender el impacto del manejo de cifras en la respuesta por parte del Estado colombiano al fenómeno objeto de estudio y la manera como las entidades comprenden los homicidios de los líderes sociales y de los defensores de derechos humanos. Para tal fin, el análisis se centra en los homicidios que hayan ocurrido desde la firma del acuerdo de paz entre el Gobierno Nacional y la guerrilla FARC – EP en octubre de 2016 hasta la fecha, así como en las causas identificadas por cada una de las entidades y de las ONG´s.

espanolEl objetivo del estudio fue examinar las propiedades psicometricas de la escala CD-RISC en poblacion adolescente chilena. La muestra fue de 520 estudiantes, en un rango etario de 13 a 19 anos, pertenecientes a establecimientos escolares de las regiones de La Araucania y Los Rios, Chile. Los resultados del analisis factorial confirmatorio determino una estructura unidimensional mediante un modelo Bifactor, compuesta por un factor general de resiliencia y dos sub dimensiones, con adecuados indicadores de ajuste (CFI=.956; RMSEA=.05). La fiabilidad mediante consistencia interna presento rangos estadisticamente esperables, con un coeficiente Omega jerarquico de .81. El nivel de invarianza de la escala para las variables sexo y edad fue escalar, no encontrandose diferencias significativas en el factor general de resiliencia. Se obtuvieron evidencias de validez convergente y discriminante. Por tanto, CD-RISC, muestra indicadores psicometricos adecuados para adolescentes chilenos evaluados y se discutieron las limitaciones del presente estudio. EnglishThis study aimed to examine the psychometric properties of the CD-RISC scale in the Chilean adolescent population. The sample was 520 students within an age range of 13 to 19 years, belonging to schools in the regions of La Araucania and Los Rios, Chile. The confirmatory factor analysis results determined a onedimensional structure using a Bifactor model, composed of a general factor of resilience and two subdimensions, with suitable adjustment indicators (CFI=.956; RMSEA=.05). Reliability through internal consistency showed statistically expected ranges, with a hierarchical Omega coefficient of .81. The level of invariance of the scale for the sex and age variables was scalar, not finding significant differences in resilience's general factor. We did find evidence of convergent and discriminant validity. Therefore, CDRISC showed consistent psychometric indicators for the Chilean adolescents evaluated. Finally, we discuss the limitations of this study.

Microcapsules (MC) based on chitosan (CH) and including nano-magnetite and erlotinib were synthesized. The microparticles were characterized by SEM, FT-IR and TGA. The percentage of encapsulation was determined, as well as its microbiological activity. Finally, the effectiveness of the formulation was evaluated in terms of cell viability and/or toxicity when compared with the reference drug. The formulation used to prepare the microcapsules showed some bacteriostatic properties. The characterization of microcapsules exhibited amorphous spherical shape and average size of 1.29, 1.58 and 1.62 mm for chitosan, chitosan + nanomagnetite and chitosan + nanomagnetite + erlotinib, respectively. The infrared spectra showed characteristic bands of the erlotinib and magnetite, confirming its internalization. The thermogravimetric analyzes indicated that the materials do not undergo changes at optimum working temperatures. The HPLC analysis showed a 52% of encapsulation. Finally, the formulation probed had lower effectiveness and less cytotoxicity, than the drug without encapsulating “in vitro” studies. For that reason several assays are in progress.

Submitted by Christianne Fontes de Andrade (cfontes@ct.ufrj.br) on 2020-03-30T23:35:54Z No. of bitstreams: 1 886826.pdf: 2592603 bytes, checksum: 27aa74a64e05d2244dae88fb57bef8f7 (MD5) Made available in DSpace on 2020-03-30T23:35:54Z (GMT). No. of bitstreams: 1 886826.pdf: 2592603 bytes, checksum: 27aa74a64e05d2244dae88fb57bef8f7 (MD5) Previous issue date: 2018-12 Este trabalho apresenta uma metodologia semi-analítica para avaliar eficientemente as integrais multidimensionais encontradas nas análises de resposta extrema de longo prazo e fadiga probabilística de estruturas offshore. Algumas metodologias tradicionais usadas tanto na avaliação da resposta extrema de longo prazo quanto na análise probabilística de fadiga de estruturas marinhas descritas na literatura são discutidas neste estudo. Além desses métodos, um novo procedimento para otimizar esses cálculos é desenvolvido e apresentado em detalhes neste trabalho. O método proposto baseia-se na interpolação paramétrica de variáveis que descrevem as séries temporais de respostas de curto prazo; por exemplo, os parâmetros estatísticos da distribuição de probabilidade de picos e os danos à fadiga de curto prazo. Este método de interpolação é então usado para avaliar eficientemente as integrais de convolução de longo prazo. Três exemplos são apresentados mostrando a eficiência e precisão do método proposto quando comparados com os métodos de integração completa (metodologia da “força bruta”). No primeiro exemplo, um modelo analítico de um grau de liberdade é analisado no domínio da frequência. No segundo exemplo, um Steel Catenary Riser (SCR) é avaliado com base em simulações no domínio do tempo. Na sequência, uma análise semelhante é realizada para um Steel Lazy Wave Riser (SLWR). This work presents a semi-analytical methodology to efficiently evaluate the multi-dimensional integrals found in the analyses of the long-term extreme response and probabilistic fatigue of offshore structures. Some traditional methodologies for longterm extreme response and probabilistic fatigue analysis of marine structures described in literature are discussed in this study. Besides these methods, a new procedure developed in this work for optimizing these calculations is explained in details. The proposed method is based on the parametric interpolation of parameters which describe the short-term time-series responses, e.g., statistical parameters of peaks probability distribution and short-term fatigue damage. This interpolation method is then used to efficiently evaluate the long-term convolution integrals. Three comprehensive examples are presented showing the efficiency and accuracy of the proposed method when compared with the complete long-term integration methods (“brute force” methodology). In the first example, an analytic model of a single degree of freedom is analyzed in the frequency domain. In the second one, a Steel Catenary Riser (SCR) is evaluated based on time-domain simulations. In the sequence, a similar analysis is performed for a Steel Lazy Wave Riser (SLWR).

Fatigue analysis of an offshore structure usually requires the numerical simulation of a huge number of loading cases to compute the long-term integral associated to the accumulated fatigue damage. Papadimitriou et al. [1] and Low and Cheung [2] proposed two distinct approaches to solve the long-term fatigue damage more efficiently. These methods are known as Asymptotic Approximation Method and Perturbation Method, respectively. This paper investigates the efficiency of these two methods in the fatigue analysis of the steel pipe of a riser suspended and moored by chains (RSAA). Since there is an analytical solution for the stress spectrum of this riser, both time and frequency domain fatigue assessments approaches are considered. The accuracy and computational efficiency of the aforementioned methods are compared with the “brute force” direct integration methodology.Copyright © 2015 by ASME