921 resultados para floristic and structural comparisons


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SnS thin films were prepared using automated chemical spray pyrolysis (CSP) technique. Single-phase, p-type, stoichiometric, SnS films with direct band gap of 1.33 eV and having very high absorption coefficient (N105/cm) were deposited at substrate temperature of 375 °C. The role of substrate temperature in determining the optoelectronic and structural properties of SnS films was established and concentration ratios of anionic and cationic precursor solutions were optimized. n-type SnS samples were also prepared using CSP technique at the same substrate temperature of 375 °C, which facilitates sequential deposition of SnS homojunction. A comprehensive analysis of both types of films was done using x-ray diffraction, energy dispersive x-ray analysis, scanning electron microscopy, atomic force microscopy, optical absorption and electrical measurements. Deposition temperatures required for growth of other binary sulfide phases of tin such as SnS2, Sn2S3 were also determined

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This book argues for novel strategies to integrate engineering design procedures and structural analysis data into architectural design. Algorithmic procedures that recently migrated into the architectural practice are utilized to improve the interface of both disciplines. Architectural design is predominately conducted as a negotiation process of various factors but often lacks rigor and data structures to link it to quantitative procedures. Numerical structural design on the other hand could act as a role model for handling data and robust optimization but it often lacks the complexity of architectural design. The goal of this research is to bring together robust methods from structural design and complex dependency networks from architectural design processes. The book presents three case studies of tools and methods that are developed to exemplify, analyze and evaluate a collaborative work flow.

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Local descriptors are increasingly used for the task of object recognition because of their perceived robustness with respect to occlusions and to global geometrical deformations. We propose a performance criterion for a local descriptor based on the tradeoff between selectivity and invariance. In this paper, we evaluate several local descriptors with respect to selectivity and invariance. The descriptors that we evaluated are Gaussian derivatives up to the third order, gray image patches, and Laplacian-based descriptors with either three scales or one scale filters. We compare selectivity and invariance to several affine changes such as rotation, scale, brightness, and viewpoint. Comparisons have been made keeping the dimensionality of the descriptors roughly constant. The overall results indicate a good performance by the descriptor based on a set of oriented Gaussian filters. It is interesting that oriented receptive fields similar to the Gaussian derivatives as well as receptive fields similar to the Laplacian are found in primate visual cortex.

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In this work we have made significant contributions in three different areas of interest: therapeutic protein stabilization, thermodynamics of natural gas clathrate-hydrates, and zeolite catalysis. In all three fields, using our various computational techniques, we have been able to elucidate phenomena that are difficult or impossible to explain experimentally. More specifically, in mixed solvent systems for proteins we developed a statistical-mechanical method to model the thermodynamic effects of additives in molecular-level detail. It was the first method demonstrated to have truly predictive (no adjustable parameters) capability for real protein systems. We also describe a novel mechanism that slows protein association reactions, called the “gap effect.” We developed a comprehensive picture of methioine oxidation by hydrogen peroxide that allows for accurate prediction of protein oxidation and provides a rationale for developing strategies to control oxidation. The method of solvent accessible area (SAA) was shown not to correlate well with oxidation rates. A new property, averaged two-shell water coordination number (2SWCN) was identified and shown to correlate well with oxidation rates. Reference parameters for the van der Waals Platteeuw model of clathrate-hydrates were found for structure I and structure II. These reference parameters are independent of the potential form (unlike the commonly used parameters) and have been validated by calculating phase behavior and structural transitions for mixed hydrate systems. These calculations are validated with experimental data for both structures and for systems that undergo transitions from one structure to another. This is the first method of calculating hydrate thermodynamics to demonstrate predictive capability for phase equilibria, structural changes, and occupancy in pure and mixed hydrate systems. We have computed a new mechanism for the methanol coupling reaction to form ethanol and water in the zeolite chabazite. The mechanism at 400°C proceeds via stable intermediates of water, methane, and protonated formaldehyde.

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Speaker: Lynda Hardman Organiser: Time: 04/02/2015 12:30-13:30 Location: B32/3077 Abstract The challenges of addressing gender inequalities in science, technology, engineering, mathematics and medicine is widely acknowledged. We currently hold a bronze award and ECS is one of many academic units in the University which has gained Athena Swan Charter status. In this seminar, Professor Lynda Hardman, Chair of the Informatics Europe working group "Women in Informatics Research and Education” will be explaining the causes of issued underlying gender inequality and constructive routes to addressing this important agenda. In undertaking to commit to an action plan which is a prerequisite of gaining charter status, the University or academic department agreed to accept and incorporate the Athena Swan six principles listed below: * To address gender inequalities requires commitment and action from everyone, at all levels of the organisation * To tackle the unequal representation of women in science requires changing cultures and attitudes across the organisation * The absence of diversity at management and policy-making levels has broad implications which the organisation will examine * The high loss rate of women in science is an urgent concern which the organisation will address * The system of short-term contracts has particularly negative consequences for the retention and progression of women in science, which the organisation recognises * There are both personal and structural obstacles to women making the transition from PhD into a sustainable academic career in science, which require the active consideration of the organisation. This seminar is designed to provide an opportunity to explore these issues NOTE: Lynda will be basing here talk on some of the work she directed as chair of the "Women in Informatics Research and Education” working group. The purpose of the working group is to actively participate and promote actions that contribute to improve gender balance in Information and Communication Sciences and Technologies. The first concrete result of the working group's activities was the publication of the booklet "More Women in Informatics Research and Education" in 2013. The booklet is a compact source of clear and simple best practices to deans and heads of departments that aim to increase the participation of women as both students and employees in their institutions. Many tips included were also inspired by colleagues already in leading positions who have already implemented actions in their institutions to attract more women and ensure their continued participation in the organization at commensurate ratios with their male colleagues. The booklet is endorsed by the European Commission and features a foreword by Neelie Kroes, Vice-President of the European Commission, responsible for the Digital Agenda.

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La butirilcolinesterasa humana (BChE; EC 3.1.1.8) es una enzima polimórfica sintetizada en el hígado y en el tejido adiposo, ampliamente distribuida en el organismo y encargada de hidrolizar algunos ésteres de colina como la procaína, ésteres alifáticos como el ácido acetilsalicílico, fármacos como la metilprednisolona, el mivacurium y la succinilcolina y drogas de uso y/o abuso como la heroína y la cocaína. Es codificada por el gen BCHE (OMIM 177400), habiéndose identificado más de 100 variantes, algunas no estudiadas plenamente, además de la forma más frecuente, llamada usual o silvestre. Diferentes polimorfismos del gen BCHE se han relacionado con la síntesis de enzimas con niveles variados de actividad catalítica. Las bases moleculares de algunas de esas variantes genéticas han sido reportadas, entre las que se encuentra las variantes Atípica (A), fluoruro-resistente del tipo 1 y 2 (F-1 y F-2), silente (S), Kalow (K), James (J) y Hammersmith (H). En este estudio, en un grupo de pacientes se aplicó el instrumento validado Lifetime Severity Index for Cocaine Use Disorder (LSI-C) para evaluar la gravedad del consumo de “cocaína” a lo largo de la vida. Además, se determinaron Polimorfismos de Nucleótido Simple (SNPs) en el gen BCHE conocidos como responsables de reacciones adversas en pacientes consumidores de “cocaína” mediante secuenciación del gen y se predijo el efecto delos SNPs sobre la función y la estructura de la proteína, mediante el uso de herramientas bio-informáticas. El instrumento LSI-C ofreció resultados en cuatro dimensiones: consumo a lo largo de la vida, consumo reciente, dependencia psicológica e intento de abandono del consumo. Los estudios de análisis molecular permitieron observar dos SNPs codificantes (cSNPs) no sinónimos en el 27.3% de la muestra, c.293A>G (p.Asp98Gly) y c.1699G>A (p.Ala567Thr), localizados en los exones 2 y 4, que corresponden, desde el punto de vista funcional, a la variante Atípica (A) [dbSNP: rs1799807] y a la variante Kalow (K) [dbSNP: rs1803274] de la enzima BChE, respectivamente. Los estudios de predicción In silico establecieron para el SNP p.Asp98Gly un carácter patogénico, mientras que para el SNP p.Ala567Thr, mostraron un comportamiento neutro. El análisis de los resultados permite proponer la existencia de una relación entre polimorfismos o variantes genéticas responsables de una baja actividad catalítica y/o baja concentración plasmática de la enzima BChE y algunas de las reacciones adversas ocurridas en pacientes consumidores de cocaína.

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Introducción: el lupus eritematoso sistémico (LES) es considerado una enfermedad de alto costo. La expresión clínica de la enfermedad depende de la ubicación geografía y la etnicidad. El objetivo de este estudio fue el calcular los costos ambulatorios relacionado al LES en una cohorte colombiana, identificar los predictores de costos y comparar nuestro resultados con otras poblaciones. Métodos: Se realizó una aproximación de tipo prevalencia en 100 pacientes LES en quienes se evaluaron los costos directos médicos, directos no médicos, indirectos e intangibles. Todos los costos médicos fueron evaluados usando una metodología abajo hacia arriba. Los costos directos fueron valorados desde una perspectiva social usando una metodología de micro-costeo. Los costos indirectos se evaluaron mediante una aproximación de capital humano, y los costos intangibles calculados a partir de los años de vida ajustados por calidad (AVAC). Se analizaron los datos por medio de un análisis multivariado. Para comparaciones con otras poblaciones todos los costos fueron expresados como la razón entre los costos y producto interno bruto nacional per cápita. Resultados: La media de costos totales fue 13.031±9.215 USD (ajustados por el factor de conversión de paridad del poder adquisitivo), lo cual representa el 1,66 del PIB per capita de Colombia. Los costos directos son el 64% de los costos totales. Los costos médicos representan el 80% de los costos directos,. Los costos indirectos fueron el 10% y los costos intangibles el 25% de los costos totales. Los medicamentos representaron el 45% de los costos directos. Mayores costos se relacionaron con el estrato socioeconómico, seguro médico privado, AVAC, alopecia, micofenolato mofetilo, y terapia anticoagulante. Los costos directos ajustados de los pacientes con LES en Colombia fueron mayores que en Norte América y en Europa. Conclusiones: el LES impone una carga económica importante para la sociedad. Los costos relacionados con la atención médica y AVAC fueron los principales contribuyentes al alto costo de la enfermedad. Estos resultados pueden ser referencia para determinar políticas en salud pública así como comparar el gasto en salud de forma internacional.

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This paper analyzes the measure of systemic importance ∆CoV aR proposed by Adrian and Brunnermeier (2009, 2010) within the context of a similar class of risk measures used in the risk management literature. In addition, we develop a series of testing procedures, based on ∆CoV aR, to identify and rank the systemically important institutions. We stress the importance of statistical testing in interpreting the measure of systemic importance. An empirical application illustrates the testing procedures, using equity data for three European banks.

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La medición de la desigualdad de oportunidades con las bases de PISA implican varias limitaciones: (i) la muestra sólo representa una fracción limitada de las cohortes de jóvenes de 15 años en los países en desarrollo y (ii) estas fracciones no son uniformes entre países ni entre periodos. Lo anterior genera dudas sobre la confiabilidad de estas mediciones cuando se usan para comparaciones internacionales: mayor equidad puede ser resultado de una muestra más restringida y más homogénea. A diferencia de enfoques previos basados en reconstrucción de las muestras, el enfoque del documento consiste en proveer un índice bidimensional que incluye logro y acceso como dimensiones del índice. Se utilizan varios métodos de agregación y se observan cambios considerables en los rankings de (in) equidad de oportunidades cuando solo se observa el logro y cuando se observan ambas dimensiones en las pruebas de PISA 2006/2009. Finalmente se propone una generalización del enfoque permitiendo otras dimensiones adicionales y otros pesos utilizados en la agregación.

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Wydział Nauk Społecznych: Instytut Socjologii

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The thesis which follows, entitled ''The Postoccidental Deconstruction and Resignification of 'Modemity': A Critical Analysis", is an exposition and criticism of the critique of occidental modemity found in a group of writings which identify their critique with a "postoccidental" point of view with respect to postcolonial studies. The general problem ofthe investigation concems the significance and reach ofthis critique of modemity in relation to the ongoing debate, in Latín American studies, about the historical relationship between Latín America, as a mu1ticultural/ structurally heterogeneous region, and the industrial societies of Euro pe and North America. A brief Preface explains the genealogy of the author's ideas on this subject Following this preface, the thesis proceeds to analyze the writings in this corpus through an intertextual, schematic approach which singles out two rnajor elements of the postoccidental critique: "coloniality" and "eurocentrism". These two main elements are investigated in the Introduction and Chapters One and Two, in terms of how they distinguish postoccidental analysis from other theoretical tendencias with which it has affinities but whose key concepts it reformu1ates in ways that are key to the unique approach which postoccidental analysis takes to modemity, the nature of the capitalist world system, colonialism, subaltemization, center/periphery and development . Chapter Three attempts a critical analysis of the foregoing postoccidentalist deconstruction according to the following question: to what extent does it succeed in deconstructing "modernity" as a term which refers to a historically articulated set of discourses whose underlying purpose has been to justify European and North American hegemony and structural asymmetries vis-a-vis the peripheries of the capitalist world system, based on an ethnocentric, racialist logic of exploitation and subalternization of non-European peoples? A Conclusion follows Chapter Three.

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Against the background of the IMF’s latest global economic forecast, Jørgen Mortensen and Cinzia Alcidi raise questions in a new CEPS Commentary about the timing of the implementation and the effects of the three main categories of economic policy – fiscal, monetary and structural.

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This paper describes a new bio-indicator method for assessing wetland ecosystem health: as such, the study is particularly relevant to current legislation such as the EU Water Framework Directive, which provides a baseline of the current status Of Surface waters. Seven wetland sites were monitored across northern Britain, with model construction data for predicting, eco-hydroloplical relationships collected from five sites during 1999, Two new sites and one repeat site were monitored during 2000 to provide model test data. The main growing season for the vegetation, and hence the sampling period, was May-August during both years. Seasonal mean concentrations of nitrate (NO3-) in surface and soil water samples during 1999 ranged from 0.01 to 14.07 mg N 1(-1), with a mean value of 1.01 mg N 1(-1). During 2000, concentrations ranged from trace level (<0.01 m- N 1(-1)) to 9.43 mg N 1(-1), with a mean of 2.73 mg N 1(.)(-1) Surface and soil-water nitrate concentrations did not influence plant species composition significantly across representative tall herb fen and mire communities. Predictive relationships were found between nitrate concentrations and structural characteristics of the wetland vegetation, and a model was developed which predicted nitrate concentrations from measures of plant diversity, canopy structure and density of reproductive structures. Two further models, which predicted stem density and density of reproductive structures respectively, utilised nitrate concentration as one of the independent predictor variables. Where appropriate, the models were tested using data collected during 2000. This approach is complementary to species-based monitoring, representing a useful and simple too] to assess ecological status in target wetland systems and has potential for bio-indication purposes.

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In many Sub-Saharan African countries, the care of chronically ill, disabled or elderly relatives is usually regarded as the responsibility of family members, within a broader landscape of often overburdened healthcare systems, the expense of medical fees, very limited access to social protection and policies that emphasise home-based care. Recent studies have demonstrated that children and youth, particularly girls and young women, take on considerable caring roles for chronically ill and elderly relatives in Africa. This article reviews the available research on young people’s caring roles and responsibilities within families affected by chronic illness and disability in Sub-Saharan Africa. I discuss how children’s caring roles challenge global and local constructions of childhood and suggest ways of conceptualising the socio-spatial and embodied dimensions of children’s everyday care work within diverse household forms. I analyse evidence on outcomes of care and children’s resilience in managing their caring responsibilities and examine the complex array of processes that influence whether children take on caring roles within the family. I argue that relational, intergenerational and lifecourse approaches to researching children’s caring responsibilities within the family have considerable potential for future geographical research and could provide further insights into the ways that care is embedded in social relations, cultural norms and structural inequalities operating in different configurations in particular places.