907 resultados para control over life


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Coarsening is a ubiquitous phenomenon [1-3] that underpins countless processes in nature, including epitaxial growth [1,3,4], the phase separation of alloys, polymers and binary fluids [2], the growth of bubbles in foams5, and pattern formation in biomembranes6. Here we show, in the first real-time experimental study of the evolution of an adsorbed colloidal nanoparticle array, that tapping-mode atomic force microscopy (TM-AFM) can drive the coarsening of Au nanoparticle assemblies on silicon surfaces. Although the growth exponent has a strong dependence on the initial sample morphology, our observations are largely consistent with modified Ostwald ripening processes [7-9]. To date, ripening processes have been exclusively considered to be thermally activated, but we show that nanoparticle assemblies can be mechanically coerced towards equilibrium, representing a new approach to directed coarsening. This strategy enables precise control over the evolution of micro- and nanostructures.

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Grounded in the intersection between gender politics and electoral studies, this dissertation examines the demobilizing effects of violations of personal space (in the form of domestic violence, control over mobility, emotional abuse, and sexual harassment) on the propensity to vote. Using quantitative methods across four survey datasets concerning Lebanon, the United States, Morocco, and Yemen, this research concludes that cross-regionally, familial control over mobility reduces the propensity to vote among women. Conversely, mechanisms of empowerment such as education and employment increase the propensity to vote.

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This study identifies and compares competing policy stories of key actors involved in the Ecuadorian education reform under President Rafael Correa from 2007-2015. By revealing these competing policy stories the study generates insights into the political and technical aspects of education reform in a context where state capacity has been eroded by decades of neoliberal policies. Since the elections in 2007, President Correa has focused much of his political effort and capital on reconstituting the state’s authority and capacity to not only formulate but also implement public policies. The concentration of power combined with a capacity building agenda allowed the Correa government to advance an ambitious comprehensive education reform with substantive results in equity and quality. At the same time the concentration of power has undermined a more inclusive and participatory approach which are essential for deepening and sustaining the reform. This study underscores both the limits and importance of state control over education; the inevitable conflicts and complexities associated with education reforms that focus on quality; and the limits and importance of participation in reform. Finally, it examines the analytical benefits of understanding governance, participation and quality as socially constructed concepts that are tied to normative and ideological interests.

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Dissertação (mestrado)—Universidade de Brasília, Faculdade de Tecnologia, Departamento de Engenharia Civil e Ambiental, 2016.

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Public participation in health-service management is an increasingly prominent policy internationally. Frequently, though, academic studies have found it marginalized by health professionals who, keen to retain control over decision-making, undermine the legitimacy of involved members of the public, in particular by questioning their representativeness. This paper examines this negotiation of representative legitimacy between staff and involved users by drawing on a qualitative study of service-user involvement in pilot cancer-genetics services recently introduced in England, using interviews, participant observation and documentary analysis. In contrast to the findings of much of the literature, health professionals identified some degree of representative legitimacy in the contributions made by users. However, the ways in which staff and users constructed representativeness diverged significantly. Where staff valued the identities of users as biomedical and lay subjects, users themselves described the legitimacy of their contribution in more expansive terms of knowledge and citizenship. My analysis seeks to show how disputes over representativeness relate not just to a struggle for power according to contrasting group interests, but also to a substantive divergence in understanding of the nature of representativeness in the context of state-orchestrated efforts to increase public participation. This divergence might suggest problems with the enactment of such aspirations in practice; alternatively, however, contestation of representative legitimacy might be understood as reflecting ambiguities in policy-level objectives for participation, which secure implementation by accommodating the divergent constructions of those charged with putting initiatives into practice.

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What is one thing in the world that we have little control over? Mother Nature. We as humans have tried to alter our natural environment countless times, and she has fought back twice as strong, leaving trails of devastation behind. The number of natural disasters has drastically increased, especially in the Southeast Asian region. The aftermath of a tsunami has left a large number of people homeless and lives forever changed. The current recovery process is chaotic and leaves affected individuals stranded without the means of rebuilding for long periods of time. This thesis aims to re-evaluate the recovery relief procedures and provide a better means of rebuilding their lives and community.

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Background Both contraceptive use and fertility rates are high fertility in Malawi. Status of women remains low and is believed to affect reproductive health decisions including use of Long Acting and Permanent Contraceptives Method (LAPCM). Objective This study seeks to examine the relationship between women empowerment and LAPCM. A measure of women’s empowerment is derived from the women’s responses to questions on the number of household decisions in which the respondent participates, employment status, type of earnings, women’s control over cash earnings and level of education. Methods The study is based on a sub sample of 5,948 married women from the 2010 Malawi Demographic and Health Survey. Data was analysed using descriptive statistics, Chi-square and multinomial logistic regression models (α=5%). Results The prevalence of current use of LAPCM was 20.0% and increases with increasing empowerment level (p<0.001). Mean age and empowerment score of women who are currently using LAPCM were 38.53±6.2 years and 6.80±2.9 respectively. Urban women (22.2%) were more currently using LAPCM than rural women (19.4%) p<0.001. Women who belong to Seven Day Adventists/Baptist were 1.51(C.I=1.058-2.153; p=0.023) more likely and Muslims were 0.58(C.I=0.410-0.809; p=0.001) less likely to currently use LAPCM than Catholic women. Being in the richest wealth quintile (OR=1.91; C.I=1.362-2.665; p<0.001) promotes current use of LAPCM than poorest. The likelihood of currently using LAPCM was higher among women who have access to FP programmes on media and increases consistently with increasing women empowerment level even when other potential confounding variables were used as control. Conclusion In Malawi, LAPCM is still underutilized and more than half of the women are not adequately empowered. Women empowerment, wealth quintile and access to FP programmes are key factors influencing the use of LAPCM. Programmes that address these determinants are urgently needed in Malawi.

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Nascida para permitir que seus criadores possam atender suas próprias necessidades, a técnica científica sempre desempenhou papel significativo na civilização humana. Este é o contexto em que podemos vislumbrar o advento da tecnociência moderna, que tem contribuído significativamente para o incremento do controle humano sobre a natureza. Este estudo tem por objetivo analisar, sob o enfoque da bioética, reflexões sobre como a filosofia da ciência entende a neutralidade da ciência e sua convergência com a racionalidade epistêmica, bem como relacionar essas reflexões ao processo de tomada de decisões na administração da tecnociência. O estudo levantou dúvidas sobre a capacidade do conhecimento tecnocientífico para legitimar e justificar as decisões no âmbito dos sistemas de ciência e tecnologia nacionais, sinalizando assim a necessidade de promover ligação entre a auto-regulação tecnocientífico e hetero-regulação bioética. ______________________________________________________________________________ ABSTRACT

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Dissertação (mestrado)—Universidade de Brasília, Instituto de Letras, Departamento de Teoria Literária e Literatura, Programa de Pós-Graduação em Literatura, 2016.

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Urbanization is associated with global biodiversity loss of macrophauna and flora through direct and indirect mechanisms, but to date few studies have examined urban soil microbes. Although there are numerous studies on the influence of agricultural management on soil microbial community composition, there has been no global-scale study of human control over urban soil microbial communities. This thesis extends the literature of urban ecology to include soil microbial communities by analyzing soils that are part of the Global Urban Soil Ecology and Education Network (GLUSEEN). Chapter 1 sets the context for urban ecology; Chapters 2 addresses patterns of community assembly, biodiversity loss, and the phylogenetic relationships among community members; Chapter 3 addresses the metabolic pathways that characterize microbial communities existing under different land-uses across varying geographic scales; and Chapter 4 relates Chapter 2 and 3 to one another and to evolutionary theory, tackling assumptions that are particular to microbial ecology.

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Size and shape tuneable ZnO nanostructures were prepared by a low frequency ultrasound (42 kHz) route using various organic solvents as the reaction media. The crystalline nature, lattice parameters and microstructural parameters such as microstrain, stress and energy density of the prepared ZnO nanostructures were revealed through X-ray diffraction (XRD) analysis. The organic solvents influenced the size and morphology of the ZnO nanostructures, and interesting morphological changes involving a spherical to triangular shaped transition were observed. The visible emission properties and lattice vibrational characteristics of the nanostructures were drastically modified by the changes in size and shape. Raman spectral measurements revealed the presence of multiphonon processes in the ZnO nanostructures. The intensity of the visible emission band was found to vary with the size and morphology of the structures. The strongest visible emission band corresponded to the structure with the largest surface/volume ratio and could be attributed to surface oxygen vacancies. The control over the size and morphology of ZnO nanostructures has been presented as a means of determining the intensity of the visible emission band

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In recent years, the area of advanced materials has been considerably, especially when it comes to materials for industrial use, such as is the case with structured porosity of catalysts suitable for catalytic processes. The use of catalysts combined with the fast pyrolysis process is an alternative to the oxygenate production of high added value, because, in addition to increasing the yield and quality of products, allows you to manipulate the selectivity to a product of interest, and therefore allows greater control over the characteristics of the final product. Based on these arguments, in this work were prepared titanium catalysts supported on MCM-41 for use in catalytic pyrolysis of biomass, called elephant grass. The reactions of pyrolysis of biomass were performed in a micro pyrolyzer, Py-5200, coupled to GC / MS, the company CDS Corporation, headquartered in the United States. The catalysts Ti-MCM-41 in different molar ratios were characterized by XRD, TG / DTG, FT-IR, SEM, XRF, UV-visible adsorption of nitrogen and the distribution of particle diameter and specific surface area measurement by the BET method. From the catalytic tests it was observed that the catalysts synthesized showed good results for the pyrolysis reaction.The main products were obtained a higher yield of aldehydes, ketones and furan. It was observed that the best reactivity is a direct function of the ratio Si/Ti, nature and concentration of the active species on mesoporous supports. Among the catalysts Ti-MCM-41 (molar ratio Si / Ti = 25 and 50), the ratio Si / Ti = 25 (400 ° C and 600 ° C) favored the cracking of oxygenates such as acids , aldehydes, ketones, furans and esters. Already the sample ratio Si / Ti = 50 had the highest yield of aromatic oxygenates

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Preparar a mudança é uma necessidade que se impõe à Administração Pública a fim de melhorar a qualidade da informação e do controlo sobre a gestão dos seus recursos humanos, financeiros e materiais. Na senda da melhoria contínua, o Exército Português tem procurado equiparar-se aos seus congéneres, explorando as tecnologias disponíveis, tendo como objetivo para 2016 dar continuidade ao desenvolvimento do projeto de implementação da Contabilidade Analítica através do Sistema Integrado de Gestão do Ministério da Defesa Nacional. A Contabilidade Analítica surge revigorada no recente Decreto-Lei nº 192/2015 - Sistema de Normalização Contabilística para as Administrações Públicas - visando satisfazer diversas necessidades de informação no processo de tomada de decisão. No entanto, este tipo de ferramenta deve ser concebida em colaboração com os decisores, no sentido de se ajustarem às reais necessidades da organização. A presente investigação aplicada tem como objetivo verificar se o Sistema Integrado de Gestão do Ministério da Defesa Nacional tem capacidade e potencialidade para disponibilizar informação analítica relevante para apoiar o processo de tomada de decisão dos Órgãos Centrais de Comando do Exército Português. Numa primeira fase, além da pesquisa bibliográfica e análise documental, foram feitas entrevistas exploratórias aos principais intervenientes que estiveram presentes nos projetos de implementação da Contabilidade Analítica levados a cabo no Exército. Posteriormente, foram entrevistados em cada Órgão Central de Comando, os Comandantes/Diretores/Chefes e os principais conselheiros na área financeira. Os resultados apontam para a existência de um considerável interesse por parte dos entrevistados relativamente à utilidade da informação analítica no apoio à tomada de decisão. Contudo, este tipo de informação não se encontra atualmente disponível, sendo necessário o reforço ou organização de um núcleo afeto em exclusividade à Contabilidade Analítica, bem como proceder à formação e mentalização dos utilizadores desta ferramenta aos vários níveis da hierarquia.

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Multimetallic shape-controlled nanoparticles offer great opportunities to tune the activity, selectivity, and stability of electrocatalytic surface reactions. However, in many cases, our synthetic control over particle size, composition, and shape is limited requiring trial and error. Deeper atomic-scale insight in the particle formation process would enable more rational syntheses. Here we exemplify this using a family of trimetallic PtNiCo nanooctahedra obtained via a low-temperature, surfactant-free solvothermal synthesis. We analyze the competition between Ni and Co precursors under coreduction “one-step” conditions when the Ni reduction rates prevailed. To tune the Co reduction rate and final content, we develop a “two-step” route and track the evolution of the composition and morphology of the particles at the atomic scale. To achieve this, scanning transmission electron microscopy and energy dispersive X-ray elemental mapping techniques are used. We provide evidence of a heterogeneous element distribution caused by element-specific anisotropic growth and create octahedral nanoparticles with tailored atomic composition like Pt1.5M, PtM, and PtM1.5 (M = Ni + Co). These trimetallic electrocatalysts have been tested toward the oxygen reduction reaction (ORR), showing a greatly enhanced mass activity related to commercial Pt/C and less activity loss than binary PtNi and PtCo after 4000 potential cycles.