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En este trabajo se ha desarrollado la implementación de una planta de concentración solar de receptor central (CRS por sus siglas en inglés Central Receiver System), conocida también como campo de helióstatos o central solar de torre, ubicada en el norte grande de nuestro país, región de Antofagasta, ciudad de Calama. La ventaja y atractivo de esta tecnología, en contraste con la experimentada de colectores cilindro parabólicos, en adelante CCP, es la mayor eficiencia que se puede obtener en el ciclo térmico de potencia, gracias a su tecnología de seguimiento en dos ejes que concentra en mayor grado la radiación solar. De esta manera, resulta posible trabajar con vapor saturado de alta temperatura, lo que se traduce en una mayor eficiencia resultante del ciclo de potencia de la central. La primera parte del trabajo se centra en explicar la modelación de la tecnología de concentración solar. En particular, se presentan los siguientes contrastes con la tecnología CCP: forma plana del reflector frente a una parabólica; sistema de seguimiento en dos ejes y no en eje único; disposición de los espejos dentro del terreno; receptor central versus al receptor distribuido de los reflectores parabólicos; distinto fluido térmico de trabajo, explicado por las distintas temperaturas de operación alcanzadas; entre otras. Posteriormente, se analiza el impacto positivo en el desempeño de la planta al incluir un sistema de almacenamiento térmico, para lo cual se procede a programar y exponer en el software Matlab® un grupo de funciones que representan la dinámica de la planta con y sin este sistema. La metodología que permite mostrar la salida eléctrica en función de la disponibilidad solar, es el balance de energía en las componentes principales de la central: campo de helióstatos, receptor, tanque de almacenamiento y generador de vapor. Un punto al cual se le prestó especial énfasis, fue la descripción del mercado eléctrico de nuestro país y los incentivos concretos, traducidos en normas, que apuntan a introducir las ERNC (energías renovables no convencionales) a la matriz energética de nuestro territorio. En particular, el mecanismo de cuotas ERNC, que exige que un porcentaje de la energía despachada por las centrales convencionales provenga de fuentes renovables, se traduce en una fuente adicional de ingresos para la central solar. Finalmente, se ha hecho confluir el aporte del sistema de almacenamiento a las posibles estrategias de despacho de la central, de modo de maximizar los ingresos por venta de energía y por suministro de potencia firme, o de suficiencia, en las horas de demanda punta. El análisis global demostró que el sistema de almacenamiento no sólo permite mejorar la eficiencia de operación de la central, por medio del despacho constante a capacidad nominal, incluso ante la presencia de un frente transitorio de nubes, sino, y de acuerdo a la revisión de los distintos indicadores financieros, que su presencia permite maximizar los ingresos obtenidos, disminuir el periodo de recuperación del capital, aumentar el VAN del proyecto y aún más destacable: hacer rentable el proyecto no convencional.

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Résumé confidentiel / Résumé confidentiel

Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2017-02-13T14:07:28Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) tese completa corrigida_junho (2016).pdf: 2219391 bytes, checksum: 7ac2338dbd07d9a53a3344311f51b5ce (MD5) / Made available in DSpace on 2017-02-13T14:07:29Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) tese completa corrigida_junho (2016).pdf: 2219391 bytes, checksum: 7ac2338dbd07d9a53a3344311f51b5ce (MD5) Previous issue date: 2014-05-26 / A artrite reumatóide (AR), é uma doença crônica inflamatória, em cuja etiologia estão envolvidos fatores genéticos, ambientais e infecções. Dentre as infecções se destacam as virais cujas proteínas modificam a função dos sinoviócitos como ocorre com o Parvovírus B19 (PVB19). Estudos tem mostrado a participação das citocinas IL-6 e L-10 na fisiopatogenia da AR. O diagnóstico da AR se baseia em critérios clínicos, radiológicos e laboratoriais.Dentre os auto- anticorpos, o fator reumatóide (FR) apresenta alta sensibilidade e baixa especificidade. Por lado, o anticorpo antipeptídeo citrulinado cíclico (ACCP) é um importante marcador para o diagnóstico e tem valor preditivo de um pior prognóstico. Sua detecção pelo ELISA, têm mostrado excelente desempenho diagnóstico, embora seja oneroso e mais demorado. Visando diagnósticos mais rápidos e práticos, os biossensores são ideais para testes tipo “point-of-care” devido à sua portabilidade. Os objetivos desta tese foram: avaliar a correlação dos niveis séricos de IL-10, IL-6 e a frequência do anti-IgG PVB19 com atividade clínica da AR mediante os índices compostos de atividade de doença (ICADs).em diferentes tratamentos e desenvolver um imunossensor eletroquímico label free para ACCP.Foi desenvolvido um estudo transversal para estimar a frequencia de anti-IgG PVB19 e determinar os níveis séricos da IL6 e IL10 pelo método ELISA.O imunossensor constituído por eletrodos screen printed de ouro,foi baseado no uso da SAM formada pela deposição do àcido tioglicólico.Oa antígenos foram imobilizadosde modo orientado via grupos carboxílicos do TGA. Os resultados mostraram uma frequencia de 73% (60/83) de IgG anti-PVB19 e uma correlação significativa entre os níveis de IL-6 e as medidas de atividade de AR nos pacientes com maior atividade inflamatória pelo EULAR. O maior contigente de pacientes IgG anti-PVB19 positivos estava com moderada e alta atividade pelo EULAR.O imunossensor eletroquímico apresentou uma resposta linear na curva de calibração, bom coeficiente de correlação e limite de detecção menor do que o método ELISA. / Rheumatoid arthritis (RA) is a chronic inflammatory disease, whose etiology is influenced by genetics, the environment, and infections. Among the various types of infections, the ones that stand out are the viral infections whose proteins alter the function of synoviocytes as occurs with Parvovirus B19 (PVB19). Studies have shown the involvement of the IL-6 and IL-10 cytokines in the physiopathogenesis of RA. Diagnosis of RA is based on clinical, radiological, and laboratory criteria. In the autoantibodies, the rheumatoid factor (RF) has high sensitivity and low specificity. The Anti-cyclic Citrullinated Peptide (anti-CCP) is an important marker for the diagnosis and as a predictive value of a worst-case prognosis.Its detection by ELISA has shown excellent diagnostic performance, but it is expensive and takes longer.Aiming for faster and more practical diagnostics, biosensors are ideal for point-of-care testing, due to their portability. The objectives of this thesis were to evaluate the correlation of the serum levels of IL-10 and IL-6and the frequency of anti-IgG PVB19,with the clinical activity of RA, via composite indices of disease activity, under different treatments, in order to develop a labelfree electrochemical immunosensor for anti-CCP. A cross-sectional study was developed to estimate the frequency of anti-IgGPVB19and to determine the serum levels of IL-6 and IL-10 by the ELISA method. The immunosensor consisting of screen-printed gold electrodes was based on the use of the self-assembled monolayer (sam) formed by deposition of thioglycolic acid. The antigens were immobilized, driven via carboxylic groups of the TGA. The results showed a frequency of 73% (60/83) of IgG anti-PVB19 and a significant correlation between the levels of IL-6 and the activity measures of AR in the patients with higher inflammatory activity according to the EULAR. Most of the IgG anti-PVB19 positive patients had moderate and high activity according to the EULAR. The electrochemical immunosensor showed a linear response in the calibration curve, a good correlation coefficient, and a detection limit lower than the ELISA method.

Le développement cérébral est une succession d'étapes aboutissant à l'établissement d'un réseau neuronal. Il fait intervenir de nombreuses molécules comme des protéines d'adhésion permettant l'interaction des neurones avec leur environnement. L'implication de nombreux gènes codant des protéines d'adhésion dans la physiopathologie de maladies neuropsychiatriques comme l'autisme souligne l'intérêt à en identifier de nouveaux. Pendant ma thèse, j'ai pu caractériser deux nouveaux gènes, Susd2 et Susd4, codant des protéines contenant des domaines CCP (Complement Control Protein), classiquement connus pour leur présence dans les protéines participant à la régulation du système du Complément. Récemment, des protéines à domaines CCP ont été décrites chez la souris comme ayant une fonction dans le développement neuronal. L'existence de nombreuses protéines prédites à domaines CCP sans fonction connue m'ont conduit à tenter de caractériser Susd2 et Susd4 qui en font partie.Susd2 est exprimé dans les neurones au sein de cultures de cellules d'hippocampe de rat. Son expression atteint un pic à un stade post natal précoce, suggérant une fonction développementale. La protéine Susd2 recombinante a une localisation neuronale diffuse, mais est particulièrement enrichie dans les synapses excitatrices. La diminution de l'expression de Susd2 a pour conséquences un défaut de croissance axonale, une augmentation de la croissance dendritique, et une inhibition spécifique de la synaptogénèse excitatrice. Susd4 est également exprimé dans les neurones, avec un pic d'expression au stade embryonnaire, et semble jouer un rôle de régulation du développement dendritique. / During brain development, several steps precisely coordinated lead to establishment of a functional neuronal network. Many molecules participate to this process, including adhesion proteins mediating interactions between neurons and their environment. Involvement of numerous genes coding for adhesion proteins in neuropsychiatric diseases such as autism argue for usefulness of identifying new ones. During my PhD, I characterized two new genes, Sud2 and Susd4, coding for proteins containing CCP domains (Complement Control Protein), classically described in proteins involved in Complement regulation system. Recently, in mammals, CCP containing proteins were shown to be involved in neuronal development. Identification of several predicted CCP containing proteins without a known function prompted me to characterize Susd2 and Susd4 which are part of them.Susd2 is expressed in neurons from hippocampal cell cultures. Its peak of expression takes place in early post natal period, suggesting a developmental function. Susd2 recombinant protein has a diffuse neuronal localization, but is particularly enriched in excitatory synapses. Decreased expression of Susd2 leads to decreased axonal growth, increased dendritic growth, and specific inhibition of excitatory synaptogenesis. Susd4 is also expressed in neurons, with a peak of expression during embryonic development, and seems to act as a regulator of dendritic growth.

<p>In silico ligand docking is a versatile and common technique when predicting ligands and inhibitors for protein binding sites. The various docking programmes aim to calculate binding energies and to predict interactions, thus identifying potential ligands.The currently available programmes lack satisfying means by which to account for structural water molecules which can either mediate protein-ligand contacts or be displaced upon ligand binding. The present project aims to generate data to facilitate the global work of developing scoring functions in docking programmes to account for structural water molecules contribution to ligand binding to fill the said void. This is done by validating the performance of docking using a simple model system (cytochrome C peroxidase (CCP) W191G) containing four well ordered, deeply buried structural water molecules which are known to either interact with a ligand or to be displaced upon ligand binding.Known ligands were docked into eight (crystallographically determined) receptor set-ups comprising the receptor and no, one or two of the water molecules. The performance was validated by comparison of the binding modes of the docked ligands and the crystal structures, comparison of docking scores of the ligands in the different set-ups, enrichment of the ligands from a database of decoys and finally by predicting new ligands from the decoy database. In addition a high resolution crystal structure of CCP W191G in complex with 3-aminopyridine (3AP) was determined in order to resolve ambiguities in the binding mode of this ligand.</p>

China is today the third largest importer of crude oil in the world. Since 1993 when the country’s consumption of oil first exceeded the capacity of its domestic production, China has become a net importer and has witnessed a growing appetite for oil during the past decade. Energy security has been given enormous emphasis in the country’s foreign policy making, and is believed to be one of the most important components of China’s foreign policy in the 21st century. While enough ink has been spilled on the assessment of what China’s energy security policy looks like, few scholarly inquiries have been made into the domestic sources of China’s energy security policy. The purpose of this article is to reevaluate such a policy by identifying the different domestic stakeholders and analyzing how the potential divergence between the state and the oil companies influences the final policy outcome.

Made available in DSpace on 2014-06-12T22:59:07Z (GMT). No. of bitstreams: 2 arquivo6620_1.pdf: 2039878 bytes, checksum: 69b02afca59a7702032716d997bea58c (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2011 / Objetivo: O propósito deste estudo foi avaliar o significado clínico de marcadores de atividade da artrite reumatóide (AR) em pacientes com Síndrome de Sjögren secundária (SSs). Materiais e Métodos: O estudo incluiu 118 pacientes distribuídos em 3 grupos: artrite reumatóide (46), AR com SSs (20) e controles saudáveis (52). Foram comparadas características clínicas e laboratoriais incluindo xerostomia, xeroftalmia, fluxo salivar em repouso (FSR), teste de Schirmer, número de articulações dolorosas e edemaciadas, escore de atividade da doença (DAS28) e dosagem de anti-CCP, Fator Reumatóide (FR), proteína C reativa (PCR), velocidade de hemossedimentação (VHS), além da análise histopatológica de glândulas salivares menores, Resultados: A dosagem anti-CCP foi detectada em 90% (18/20) dos pacientes com SSs à AR, 84,7% (39/46) dos pacientes com AR sem SSs e 1,9% (1/52) pacientes do grupo controle (p=0,181). O FR foi detectado em 75% (15/20) dos pacientes com SSs à AR, 63% (29/46) dos pacientes com AR sem SSs e em nenhum paciente do grupo controle (p=0,235). A média do número de articulações dolorosas em pacientes com SSs à AR foi de 3,53 e nos pacientes com AR sem SSs foi de 7,53 (p=0,054). Conclusões: Não houve diferença estatisticamente significante entre os grupos AR em relação aos exames anti-CCP e FR. O número de articulações dolorosas nos pacientes com AR sem SSs foi maior do que nos pacientes com SSs à AR

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