975 resultados para |Cu x|[Si yAl]-MFI
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Si(100) and Ge(100) substrates essential for subsequent III-V integration were studied in the hydrogen ambient of a metalorganic vapor phase epitaxy reactor. Reflectance anisotropy spectroscopy (RAS) enabled us to distinguish characteristic configurations of vicinal Si(100) in situ: covered with oxide, cleaned by thermal removing in H2, and terminated with monohydrides when cooling in H2 ambient. RAS measurements during cooling in H2 ambient after the oxide removal process revealed a transition from the clean to the monohydride terminated Si(100) surface dependent on process temperature. For vicinal Ge(100) we observed a characteristic RA spectrum after annealing and cooling in H2 ambient. According to results from X-ray photo electron spectroscopy and Fourier-transform infrared spectroscopy the spectrum corresponds to the monohydride terminated Ge(100) surface.
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Resumen En la ltima dcada la tecnologa lser se ha convertido en una herramienta imprescindible en la fabricacin de dispositivos fotovoltaicos, muy especialmente en aquellos basados en tecnologa de lmina delgada. Independientemente de crisis coyunturales en el sector, la evolucin en los prximos aos de estas tecnologas seguir aprovechndose de la flexibilidad y calidad de proceso de la herramienta lser para la consecucin de los dos objetivos bsicos que harn de la fotovoltaica una opcin energtica econmicamente viable: la reduccin de costes de fabricacin y el aumento de eficiencia de los dispositivos. Dentro de las tecnologas fotovoltaicas de lmina delgada, la tecnologa de dispositivos basados en silicio amorfo ha tenido un gran desarrollo en sistemas estndar en configuracin de superestrato, pero su limitada eficiencia hace que su supervivencia futura pase por el desarrollo de formatos en configuracin de substrato sobre materiales flexibles de bajo coste. En esta aproximacin, las soluciones industriales basadas en lser actualmente disponibles para la interconexin monoltica de dispositivos no son aplicables, y desde hace aos se viene investigando en la bsqueda de soluciones apropiadas para el desarrollo de dichos procesos de interconexin de forma que sean transferibles a la industria. En este contexto, esta Tesis propone una aproximacin completamente original, demostrando la posibilidad de ejecutar una interconexin completa de estos dispositivos irradiando por el lado de la lmina (es decir de forma compatible con la opcin de configuracin de substrato y, valga la redundancia, con el substrato del dispositivo opaco), y con fuentes lser emitiendo en UV. Este resultado, obtenido por primera vez a nivel internacional con este trabajo, aporta un conocimiento revelador del verdadero potencial de estas fuentes en el desarrollo industrial futuro de estas tecnologas. Si bien muy posiblemente la solucin industrial final requiera de una solucin mixta con el empleo de fuentes en UV y, posiblemente, en otras longitudes de onda, esta Tesis y su planteamiento novedoso aportan un conocimiento de gran valor a la comunidad internacional por la originalidad del planteamiento seguido, los resultados parciales encontrados en su desarrollo (un nmero importante de los cuales han aparecido en revistas del JCR que recogen en la actualidad un nmero muy significativo de citas) y porque saca adems a la luz, con las consideraciones fsicas pertinentes, las limitaciones intrnsecas que el desarrollo de procesos de ablacin directa selectiva con lseres UV en parte de los materiales utilizados presenta en el rango temporal de interaccin de ns y ps. En este trabajo se han desarrollado y optimizado los tres pasos estndar de interconexin (los habitualmente denominados Pl, P2 y P3 en la industria fotovoltaica) demostrando las ventajas y limitaciones del uso de fuentes en UV tanto con ancho temporal de ns como de ps. En particular destaca, por el xito en los resultados obtenidos, el estudio de procesos de ablacin selectiva de xidos conductores transparentes (en este trabajo utilizados tanto como contacto frontal as como posterior en los mdulos) que ha generado resultados, de excelente acogida cientfica a nivel internacional, cuya aplicacin trasciende el mbito de las tecnologas de silicio amorfo en lmina delgada. Adems en este trabajo de Tesis, en el desarrollo del objetivo citado, se han puesto a punto tcnicas de anlisis de los procesos lser, basadas en mtodos avanzados de caracterizacin de materiales (como el uso combinado de la espectroscopia dispersiva de rayos X y la microscopa confocal de barrido) que se presentan como autnticos avances en el desarrollo de tcnicas especficas de caracterizacin para el estudio de los procesos con lser de ablacin selectiva de materiales en lmina delgada, procesos que no solo tienen impacto en el mbito de la fotovoltaica, sino tambin en la microelectrnica, la biotecnologa, la microfabricacin, etc. Como resultado adicional, parte de los resultados de este trabajo, han sido aplicados exitosamente por el grupo de investigacion en la que la autora desarrolla su labor para conseguir desarrollar procesos de enorme interes en otras tec-nologas fotovoltaicas, como las tecnologas estandar de silicio amorfo sobre vidrio en configuracion de superestrato o el procesado de capas delgadas en tecnologas convencionales de silicio cristalino. Por ultimo decir que este trabajo ha sido posible por una colaboracion muy estrecha entre el Centro Laser de la UPM, en el que la autora desarrolla su labor, y el Grupo de Silicio Depositado del Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas, CIEMAT, que, junto al Grupo de Energa Fotovoltaica de la Universidad de Barcelona, han preparado la mayor parte de las muestras utilizadas en este estudio. Dichas colaboraciones se han desarrollado en el marco de varios proyectos de investigacion aplicada con subvencion publica, tales como el proyecto singular estrategico PSE-MICROSIL08 (PSE-120000-2006-6), el proyecto INNDISOL (IPT-420000-2010-6), ambos financiados porel Fondo Europeo de Desarrollo Regional FEDER (UE) Una manera de hacer Europa y el MICINN, y los proyectos de Plan Nacional AMIC (ENE2010-21384-C04- 02) y CLASICO (ENE2007-6772-C04-04), cuya financiacion ha permitido en gran parte llevar a termino este trabajo Abstract In the last decade, the laser technology has turned into an indispensable tool in the production of photovoltaic devices, especially of those based on thin film technology. Regardless the current crisis in the sector, the evolution of these technologies in the upcoming years will keep taking advantage of the flexibility and process quality of the laser tool for the accomplishment of the two basic goals that will convert the photovoltaic energy into economically viable: the manufacture cost reduction and the increase in the efficiency of the devices. Amongst the thin film laser technologies, the technology of devices based on amorphous silicon has had a great development in standard systems of superstrate configuration, but its limited efficiency makes its survival dependant on the development of formats in substrate configuration with low cost flexible materials. In this approach, the laser industrial solutions currently available for the monolithic interconnection are not applicable, and in the last few years the investigations have been focused on the search of appropriate solutions for the development of such interconnection processes in a way that the same are transferable to the industry. In this context, this Thesis proposes a totally original approach, proving the possibility of executing a full interconnection of these devices by means of irradiation from the film side, i.e., compatible with the substrate configuration, and with UV laser sources. This result, obtained for the first time at international level in this work, provides a revealing knowledge of the true potential of these sources in the future industrial development of these technologies. Even though very probably the final industrial solution will require a combination of the use of UV sources along with other wavelengths, this Thesis and its novel approach contribute with a high value to the international community because of the originality of the approach, the partial results found throughout its development (out of which, a large number has appeared in JCR journals that currently accumulate a significant number of citations) and brings to light, with the pertinent scientific considerations, the intrinsic limitations that the selective direct ablation processes with UV laser present in the temporal range of interaction of ns and ps for part of the materials used in this study. More particularly, the three standard steps of interconnection (usually denominated P1, P2 and P3 in the photovoltaic industry) have been developed and optimized, showing the advantages as well as the limitations of the use of UV sources in both the ns and ps pulse-width ranges. It is highly remarkable, because of the success in the obtained results, the study of selective ablation processes in transparent conductive oxide (in this work used as a front and back contact), that has generated results, of excellent international scientific reception, whose applications go beyond the scope of thin film photovoltaic technologies based on amorphous silicon. Moreover, in this Thesis, with the development of the mentioned goal, different techniques of analysis of laser processes have been fine-tuned, basing the same in advanced methods for material characterization (like the combined use of EDX Analysis and Confocal Laser Scanning Microscopy) that can be presented as true breakthroughs in the development of specific techniques for characterization in the study of laser processes of selective ablation of materials in thin film technologies, processes that not only have impact in the photovoltaic field, but also in those of microelectronics, biotechnology, micro-fabrication, etc. As an additional outcome, part of the results of this work has been successfully applied, by the investigation group to which the author belongs, to the development of processes of enormous interest within other photovoltaic technologies, such as the standard technologies on amorphous silicon over glass in superstrate configuration or the processing of thin layers in conventional technologies using crystalline silicon. Lastly, it is important to mention that this work has been possible thanks to the close cooperation between the Centro Laser of the UPM, in which the author develops her work, and the Grupo de Silicio Depositado of Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas, CIEMAT, which, along with the Grupo de Energa Fotovoltaica of Universidad de Barcelona, has prepared the largest part of the samples utilized in this study. Such collaborations have been carried out in the context of several projects of applied investigation with public funding, like Proyecto Singular Estrategico PSE-MICROSIL08 (PSE-120000-2006-6), Proyecto IN-NDISOL (IPT-420000-2010-6), both funded by the European Regional Development Fund (ERDF), Una manera de hacer Europa and MICINN, and the projects of Plan Nacional AMIC (ENE2010-21384-C04-02) and CLASICO (ENE2007-6772-C04-04), whose funds have enabled the devel-opment of large part of this work.
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La influencia del cereal principal de la dieta y el tipo de molienda sobre los parmetros productivos y la calidad del huevo fue estudiada en 420 ponedoras rubias de la estirpe Hy -Line en el perodo 24 a 59 semanas de vida. Se utiliz un diseo completamente al azar con 6 tratamientos ordenados factorialmente bajo un esquema 3 x 2, con 3 tipos de cereales (cebada, trigo blando y maz) y dos tipos de moliendas (molino de martillo o molino de rodillos). Cada tratamiento fue replicado 7 veces y la unidad experimental consisti una jaula enriquecida con 10 gallinas. Las variables productivas de las aves fueron analizadas en periodos de 28 das y las variables de calidad del huevo fueron medidas en la semana 40 y 56 de vida respectivamente. El tamao medio de partcula fue mayor en las dietas basadas en cebada que en las dietas basada en trigo o maz, siendo estas diferencias ms pronunciadas cuando se utiliz el martillo de rodillo para moler las dietas. La proporcin de partculas menores de 2500 m disminuy con la utilizacin del molino de rodillo respecto al molino de martillo (13.2% vs. 6.0%). Teniendo en cuenta el periodo global del experimento, el consumo medio diario fue mayor en las gallinas que consumieron tanto trigo como maz respecto a las que consumieron cebada (110.8 y 110.7 vs. 109.7 g/d; P< 0.05). Varias nteracciones fueron detectadas entre el cereal principal de la dieta y el tipo de molino utilizado, as el consumo medio diario (P< 0.01) y el porcentaje de puesta (P=0.09) fue similar en todas las dietas cuando el molino de martillo fue utilizado, sin embargo, ambas variables empeoraron cuando el molino de rodillo fue utilizado en la dieta basada en cebada respecto a la basada en trigo o maz. A pesar de estos efectos, tanto en el consumo diario como en la puesta, ninguna de las variables productivas restantes fue afectada por el tratamiento. En cuanto a las variables relacionadas con la calidad de huevo, ninguna de las variables estudiadas fue afectada por el tratamiento. Con estas premisas, podemos concluir que el molino de rodillo puede utilizarse de forma exitosa para moler dietas basadas en cereales, especialmente trigo y maz. Sin embargo, el molino de rodillo quiz no se adecuado para moler cereales con un porcentaje de fibra elevado como es el caso de la cebada.
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Los virus de plantas pueden causar enfermedades severas que conllevan serias prdidas econmicas a nivel mundial. Adems, en la naturaleza son comunes las infecciones simultneas con distintos virus que conducen a la exacerbacin de los sntomas de enfermedad, fenmeno al que se conoce como sinergismo viral. Una de las sintomatologas ms severas causadas por los virus en plantas susceptibles es la necrosis sistmica (NS), que incluso puede conducir a la muerte del husped. Este fenotipo ha sido comparado en ocasiones con la respuesta de resistencia de tipo HR, permitiendo establecer una serie de paralelismos entre ambos tipos de respuesta que sugieren que la NS producida en interacciones compatibles sera el resultado de una respuesta hipersensible sistmica (SHR). Sin embargo, los mecanismos moleculares implicados en el desarrollo de la NS, su relacin con procesos de defensa antiviral o su relevancia biolgica an no son bien entendidos, al igual que tampoco han sido estudiados los cambios producidos en la planta a escala genmica en infecciones mltiples que muestran sinergismo en patologa. En esta tesis doctoral se han empleado distintas aproximaciones de anlisis de expresin gnica, junto con otras tcnicas genticas y bioqumicas, en el sistema modelo de Nicotiana benthamiana para estudiar la NS producida por la infeccin sinrgica entre el Virus X de la patata (PVX) y diversos potyvirus. Se han comparado los cambios producidos en el husped a nivel genmico y fisiolgico entre la infeccin doble con PVX y el Virus Y de la patata (PVY), y las infecciones simples con PVX o PVY. Adems, los cambios transcriptmicos y hormonales asociados a la infeccin con la quimera viral PVX/HCPro, que reproduce los sntomas del sinergismo entre PVXpotyvirus, se han comparado con aquellos producidos por otros dos tipos de muerte celular, la PCD ligada a una interaccin incompatible y la PCD producida por la disfuncin del proteasoma. Por ltimo, tcnicas de gentica reversa han permitido conocer la implicacin de factores del husped, como las oxilipinas, en el desarrollo de la NS asociada al sinergismo entre PVXpotyvirus. Los resultados revelan que, respecto a las infecciones con solo uno de los virus, la infeccin doble con PVXPVY produce en el husped diferencias cualitativas adems de cuantitativas en el perfil transcriptmico relacionado con el metabolismo primario. Otros cambios en la expresin gnica, que reflejan la activacin de mecanismos de defensa, correlacionan con un fuerte estrs oxidativo en las plantas doblemente infectadas que no se detecta en las infecciones simples. Adems, medidas en la acumulacin de determinados miRNAs implicados en diversos procesos celulares muestran como la infeccin doble altera de manera diferencial tanto la acumulacin de estos miRNAs como su funcionalidad, lo cual podra estar relacionado con los cambios en el transcriptoma, as como con la sintomatologa de la infeccin. La comparacin a nivel transcriptmico y hormonal entre la NS producida por PVX/HCPro y la interaccin incompatible del Virus del mosaico del tabaco en plantas que expresan el gen N de resistencia (SHR), muestra que la respuesta en la interaccin compatible es similar a la que se produce durante la SHR, si bien se presenta de manera retardada en el tiempo. Sin embargo, los perfiles de expresin de genes de defensa y de respuesta a hormonas, as como la acumulacin relativa de cido saliclico (SA), cido jasmonico (JA) y cido abscsico, en la interaccin compatible son ms semejantes a la respuesta PCD producida por la disfuncin del proteasoma que a la interaccin incompatible. Estos datos sugieren una contribucin de la interferencia sobre la funcionalidad del proteasoma en el incremento de la patogenicidad, observado en el sinergismo PVXpotyvirus. Por ltimo, los resultados obtenidos al disminuir la expresin de 9LOX, DOX1 y COI1, relacionados con la sntesis o con la sealizacin de oxilipinas, y mediante la aplicacin exgena de JA y SA, muestran la implicacin del metabolismo de las oxilipinas en el desarrollo de la NS producida por la infeccin sinrgica entre PVXpotyvirus en N. benthamiana. Adems, estos resultados indican que la PCD asociada a esta infeccin, al igual que ocurre en interacciones incompatibles, no contiene necesariamente la acumulacin viral, lo cual indica que necrosis e inhibicin de la multiplicacin viral son procesos independientes. ABSTRACT Plant viruses cause severe diseases that lead to serious economic losses worldwide. Moreover, simultaneous infections with several viruses are common in nature leading to exacerbation of the disease symptoms. This phenomenon is known as viral synergism. Systemic necrosis (SN) is one of the most severe symptoms caused by plant viruses in susceptible plants, even leading to death of the host. This phenotype has been compared with the hypersensitive response (HR) displayed by resistant plants, and some parallelisms have been found between both responses, which suggest that SN induced by compatible interactions could be the result of a systemic hypersensitive response (SHR). However, the molecular mechanisms involved in the development of SN, its relationship with antiviral defence processes and its biological relevance are still unknown. Furthermore, the changes produced in plants by mixed infections that cause synergistic pathological effects have not been studied in a genomewide scale. In this doctoral thesis different approaches have been used to analyse gene expression, together with other genetic and biochemical techniques, in the model plant Nicotiana benthamiana, in order to study the SN produced by the synergistic infection of Potato virus X (PVX) with several potyviruses. Genomic and physiological changes produced in the host by double infection with PVX and Potato virus Y (PVY), and by single infection with PVX or PVY have been compared. In addition, transcriptional and hormonal changes associated with infection by the chimeric virus PVX/HCPro, which produces synergistic symptoms similar to those caused by PVXpotyvirus, have been compared with those produced by other types of cell death. These types of cell death are: PCD associated with an incompatible interaction, and PCD produced by proteasome disruption. Finally, reverse genetic techniques have revealed the involvement of host factors, such as oxylipins, in the development of SN associated with PVXpotyvirus synergism. The results revealed that compared with single infections, double infection with PVXPVY produced qualitative and quantitative differences in the transcriptome profile, mainly related to primary metabolism. Other changes in gene expression, which reflected the activation of defence mechanisms, correlated with a severe oxidative stress in doubly infected plants that was undetected in single infections. Additionally, accumulation levels of several miRNAs involved in different cellular processes were measured, and the results showed that double infection not only produced the greatest variations in miRNA accumulation levels but also in miRNA functionality. These variations could be related with transcriptomic changes and the symptomatology of the infection. Transcriptome and hormone level comparisons between SN induced by PVX/HCPro and the incompatible interaction produced by Tobacco mosaic virus in plants expressing the N resistance gene (SHR), showed some similarities between both responses, even though the compatible interaction appeared retarded in time. Nevertheless, the expression profiles of both defencerelated genes and hormoneresponsive genes, as well as the relative accumulation of salicylic acid (SA), jasmonic acid (JA) and abscisic acid in the compatible interaction are more similar to the PCD response produced by proteasome disruption. These data suggest that interference with proteasome functionality contributes to the increase in pathogenicity associated with PVXpotyvirus synergism. Finally, the results obtained by reducing the expression of 9LOX, DOX1 and COI1, related with synthesis or signalling of oxylipins, and by applying exogenously JA and SA, revealed that oxylipin metabolism is involved in the development of SN induced by PVXpotyvirus synergistic infections in N. benthamiana. Moreover, these results also indicated that PVXpotyvirus associated PCD does not necessarily restrict viral accumulation, as is also the case in incompatible interactions. This indicates that both necrosis and inhibition of viral multiplication are independent processes.
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The aim of this work is to provide the necessary methods to register and fuse the endo-epicardial signal intensity (SI) maps extracted from contrast-enhanced magnetic resonance imaging (ceMRI) with X-ray coronary ngiograms using an intrinsic registrationbased algorithm to help pre-planning and guidance of catheterization procedures. Fusion of angiograms with SI maps was treated as a 2D-3D pose estimation, where each image point is projected to a Plcker line, and the screw representation for rigid motions is minimized using a gradient descent method. The resultant transformation is applied to the SI map that is then projected and fused on each angiogram. The proposed method was tested in clinical datasets from 6 patients with prior myocardial infarction. The registration procedure is optionally combined with an iterative closest point algorithm (ICP) that aligns the ventricular contours segmented from two ventriculograms.
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El dolor es un sntoma frecuente en la prctica mdica. En Espaa, un estudio realizado en el ao 2000 demostr que cada mdico atiende un promedio de 181 pacientes con dolor por mes, la mayora de ellos con dolor crnico moderado1. Del 7%-8% de la poblacin europea est afectada y hasta el 5% puede ser grave2-3, se estima, que afecta a ms de dos millones de espaoles4. En la consulta de Atencin Primaria, los pacientes con dolor neuroptico tienen tasas de depresin mucho mayores 5-6-7. El dolor neuroptico8 es el dolor causado por dao o enfermedad que afecta al sistema somato-sensorial, es un problema de salud pblica con un alto coste laboral, debido a que existe cierto desconocimiento de sus singularidades, tanto de su diagnstico como de su tratamiento, que al fallar, el dolor se perpeta y se hace ms rebelde a la hora de tratarlo, en la mayora de las ocasiones pasa a ser crnico. Los mecanismos fisiopatolgicos son evolutivos, se trata de un proceso progresivo e integrado que avanza si no recibe tratamiento, ocasionando graves repercusiones en la calidad de vida de los pacientes afectados9. De acuerdo a Prusiner (premio nobel de medicina 1997), en todas las enfermedades neurodegenerativas hay algn tipo de proceso anormal de la funcin neuronal. Las enfermedades neurodegenerativas son la consecuencia de anormalidades en el proceso de ciertas protenas que intervienen en el ciclo celular, por lo tanto da lugar al cmulo de las mismas en las neuronas o en sus proximidades, disminuyendo o anulando sus funciones, como la enfermedad de Alzheimer y el mismo SXF. La protena FMRP (Fragile Mental Retardation Protein), esencial para el desarrollo cognitivo normal, ha sido relacionada con la va piramidal del dolor10-11-12. El Sndrome de X Frgil13-14 (SXF), se debe a la mutacin del Gen (FMR-1). Como consecuencia de la mutacin, el gen se inactiva y no puede realizar la funcin de sintetizar la protena FMRP. Por su incidencia se le considera la primera causa de Deficiencia Mental Hereditaria slo superada por el Sndrome de Down. La electroencefalografa (EEG) es el registro de la actividad bioelctrica cerebral que ha trado el desarrollo diario de los estudios clnicos y experimentales para el descubrimiento, diagnstico y tratamiento de un gran nmero de anormalidades neurolgicas y fisiolgicas del cerebro y el resto del sistema nervioso central (SNC) incluyendo el dolor. El objetivo de la presente investigacin es por medio de un estudio multimodal, desarrollar nuevas formas de presentacin diagnstica mediante tcnicas avanzadas de procesado de seal y de imagen, determinando as los vnculos entre las evaluaciones cognitivas y su correlacin anatmica con la modulacin al dolor presente en patologas relacionadas con protena FMRP. Utilizando tcnicas biomdicas (funcionalestructural) para su caracterizacin. Para llevar a cabo esta tarea hemos utilizado el modelo animal de ratn. Nuestros resultados en este estudio multimodal demuestran que hay alteraciones en las vas de dolor en el modelo animal FMR1-KO, en concreto en la modulacin enceflica (dolor neuroptico), los datos se basan en los resultados del estudio estructural (imagen histologa), funcional (EEG) y en pruebas de comportamiento (Laberinto de Barnes). En la Histologa se muestra una clara asimetra estructural en el modelo FMR1 KO con respecto al control WT, donde el hemisferio Izquierdo tiene mayor densidad de masa neuronal en KO hembras 56.7%-60.8%, machos 58.3%-61%, en WT hembras 62.7%-62.4%, machos 55%-56.2%, hemisferio derecho-izquierdo respectivamente, esto refleja una correlacin entre hemisferios muy baja en los sujetos KO (~50%) con respecto a los control WT (~90%). Se encontr correlacin significativa entre las pruebas de memoria a largo plazo con respecto a la asimetra hemisfrica (r = -0.48, corregido <0,05). En el estudio de comportamiento tambin hay diferencias, los sujetos WT tuvieron 22% un de rendimiento en la memoria a largo plazo, mientras que en los machos hay deterioro de memoria de un 28% que se corresponden con la patologa en humanos. En los resultados de EEG estudiados en el hemisferio izquierdo, en el rea de la corteza insular, encuentran que la latencia de la respuesta al potencial evocado es menor (22vs32 15vs96seg), la intensidad de la seal es mayor para los sujetos experimentales FMR1 KO frente a los sujetos control, esto es muy significativo dados los resultados en la histologa (140vs129 145vs142 mv). Este estudio multimodal corrobora que las manifestaciones clnicas del SXF son variables dependientes de la edad y el sexo. Hemos podido corroborar en el modelo animal que en la etapa de adulto, los varones con SXF comienzan a desarrollar problemas en el desempeo de tareas que requieren la puesta en marcha de la funcin ejecutiva central de la memoria de trabajo (almacenamiento temporal). En el anlisis del comportamiento es difcil llegar a una conclusin objetiva, se necesitan ms estudios en diferentes etapas de la vida corroborados con resultados histolgicos. Los avances logrados en los ltimos aos en su estudio han sido muy positivos, de tal modo que se estn abriendo nuevas vas de investigacin en un conjunto de procesos que representan un gran desafo a problemas mdicos, asistenciales, sociales y econmicos a los que se enfrentan los principales pases desarrollados, con un aumento masivo de las expectativas de vida y de calidad. Las herramientas utilizadas en el campo de las neurociencias nos ofrecen grandes posibilidades para el desarrollo de estrategias que permitan ser utilizadas en el rea de la educacin, investigacin y desarrollo. La gentica determina la estructura del cerebro y nuestra investigacin comprueba que la ausencia de FMRP tambin podra estar implicada en la modulacin del dolor como parte de su expresin patolgica siendo el modelo animal un punto importante en la investigacin cientfica fundamental para entender el desarrollo de anormalidades en el cerebro. ABSTRACT Pain is a common symptom in medical practice. In Spain, a study conducted in 2000 each medical professional treats an average of 181 patients with pain per month, most of them with chronic moderate pain. 7% -8% of the European population is affected and up to 5% can be serious, it is estimated to affect more than two million people in Spain. In Primary Care, patients with neuropathic pain have much higher rates of depression. Neuropathic pain is caused by damage or disease affecting the somatosensory system, is a public health problem with high labor costs, there are relatively unfamiliar with the peculiarities in diagnosis and treatment, failing that, the pain is perpetuated and becomes rebellious to treat, in most cases becomes chronic. The pathophysiological mechanisms are evolutionary, its a progressive, if untreated, causing severe impact on the quality of life of affected patients. According to Prusiner (Nobel Prize for Medicine 1997), all neurodegenerative diseases there is some abnormal process of neuronal function. Neurodegenerative diseases are the result of abnormalities in the process of certain proteins involved in the cell cycle, reducing or canceling its features such as Alzheimer's disease and FXS. FMRP (Fragile Mental Retardation Protein), is essential for normal cognitive development, and has been linked to the pyramidal tract pain. Fragile X Syndrome (FXS), is due to mutation of the gene (FMR-1). As a consequence of the mutation, the gene is inactivated and can not perform the function of FMRP synthesize. For its incidence is considered the leading cause of Mental Deficiency Hereditary second only to Down Syndrome. Electroencephalography (EEG) is the recording of bioelectrical brain activity, is a advancement of clinical and experimental studies for the detection, diagnosis and treatment of many neurological and physiological abnormalities of the brain and the central nervous system, including pain. The objective of this research is a multimodal study, is the development of new forms of presentation using advanced diagnostic techniques of signal processing and image, to determine the links between cognitive evaluations and anatomic correlation with pain modulation to this protein FMRP-related pathologies. To accomplish this task have used the mouse model. Our results in this study show alterations in multimodal pain pathways in FMR1-KO in brain modulation (neuropathic pain), the data are based on the results of the structural study (histology image), functional (EEG) testing and behavior (Barnes maze). Histology In structural asymmetry shown in FMR1 KO model versus WT control, the left hemisphere is greater density of neuronal mass (KO females 56.7% -60.8%, 58.3% -61% males, females 62.7% -62.4 WT %, males 55% -56.2%), respectively right-left hemisphere, this reflects a very low correlation between hemispheres in KO (~ 50%) subjects compared to WT (~ 90%) control. Significant correlation was found between tests of long-term memory with respect to hemispheric asymmetry (r = -0.48, corrected <0.05). In the memory test there are differences too, the WT subjects had 22% yield in long-term memory, in males there memory impairment 28% corresponding to the condition in humans. The results of EEG studied in the left hemisphere, in insular cortex area, we found that the latency of the response evoked potential is lower (22vs32 15vs96seg), the signal strength is higher for the experimental subjects versus FMR1 KO control subjects, this is very significant given the results on histology (140vs129 145vs142 mv). This multimodal study confirms that the clinical manifestations of FXS are dependent variables of age and sex. We have been able to corroborate in the animal model in the adult stage, males with FXS begin developing problems in the performance of tasks that require the implementation of the central executive function of working memory (temporary storage). In behavior analysis is difficult to reach an objective conclusion, more studies are needed in different life stages corroborated with histologic findings. Advances in recent years were very positive, being opened new lines of research that represent a great challenge to physicians, health care, social and economic problems facing the major developed countries, with a massive increase in life expectancy and quality. The tools used in the field of neuroscience offer us great opportunities for the development of strategies to be used in the area of education, research and development. Genetics determines the structure of the brain and our research found that the absence of FMRP might also be involved in the modulation of pain as part of their pathological expression being an important animal model in basic scientific research to understand the development of abnormalities in brain.
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The main objective of this work is to adapt the Laser Induced Forward Techniques (LIFT), a well- known laser direct writing technique for material transfer, to define metallic contacts (fingers and busbars) onto c-Si cells. The silver paste (with viscosity around 30-50 kcPs) is applied over a glass substrate using a coater. The thickness of the paste can be control changing the deposit parameters. The glass with the silver paste is set at a controlled gap over the c-Si cell. A solid state pulsed laser (532 nm) is focused at the glass/silver interface producing a droplet of silver that it is transferred to the c-Si cell. A scanner is used to print lines. The process parameters (silver paste thickness, gap and laser parameters -spot size, pulse energy and overlapping of pulses) are modified and the morphology of the lines is studied using confocal microscopy. Long lines are printed and the uniformity (in thickness and height) is studied. Some examples of metallization of larger areas (up to 10 cm x 10 cm) are presented.
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The crystal structure of raite was solved and refined from data collected at Beamline Insertion Device 13 at the European Synchrotron Radiation Facility, using a 3 3 65 m single crystal. The refined lattice constants of the monoclinic unit cell are a = 15.1(1) ; b = 17.6(1) ; c = 5.290(4) ; = 100.5(2); space group C2/m. The structure, including all reflections, refined to a final R = 0.07. Raite occurs in hyperalkaline rocks from the Kola peninsula, Russia. The structure consists of alternating layers of a hexagonal chicken-wire pattern of 6-membered SiO4 rings. Tetrahedral apices of a chain of Si six-rings, parallel to the c-axis, alternate in pointing up and down. Two six-ring Si layers are connected by edge-sharing octahedral bands of Na+ and Mn3+ also parallel to c. The band consists of the alternation of finite MnMn and NaMnNa chains. As a consequence of the misfit between octahedral and tetrahedral elements, regions of the SiO layers are arched and form one-dimensional channels bounded by 12 Si tetrahedra and 2 Na octahedra. The channels along the short c-axis in raite are filled by isolated Na(OH,H2O)6 octahedra. The distorted octahedrally coordinated Ti4+ also resides in the channel and provides the weak linkage of these isolated Na octahedra and the mixed octahedral tetrahedral framework. Raite is structurally related to intersilite, palygorskite, sepiolite, and amphibole.
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Recent major advances in x-ray imaging and spectroscopy of clusters have allowed the determination of their mass and mass profile out to 1/2 the virial radius. In rich clusters, most of the baryonic mass is in the gas phase, and the ratio of mass in gas/stars varies by a factor of 24. The baryonic fractions vary by a factor of 3 from cluster to cluster and almost always exceed 0.09 h50[3/2] and thus are in fundamental conflict with the assumption of = 1 and the results of big bang nucleosynthesis. The derived Fe abundances are 0.20.45 solar, and the abundances of O and Si for low redshift systems are 0.61.0 solar. This distribution is consistent with an origin in pure type II supernova. The amount of light and energy produced by these supernovae is very large, indicating their importance in influencing the formation of clusters and galaxies. The lack of evolution of Fe to a redshift of z 0.4 argues for very early enrichment of the cluster gas. Groups show a wide range of abundances, 0.10.5 solar. The results of an x-ray survey indicate that the contribution of groups to the mass density of the universe is likely to be larger than 0.1 h502. Many of the very poor groups have large x-ray halos and are filled with small galaxies whose velocity dispersion is a good match to the x-ray temperatures.
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Cu,Zn-superoxide dismutase (SOD) is known to be a locus of mutation in familial amyotrophic lateral sclerosis (FALS). Transgenic mice that express a mutant Cu,Zn-SOD, Gly-93--> Ala (G93A), have been shown to develop amyotrophic lateral sclerosis (ALS) symptoms. We cloned the FALS mutant, G93A, and wild-type cDNA of human Cu,Zn-SOD, overexpressed them in Sf9 insect cells, purified the proteins, and studied their enzymic activities for catalyzing the dismutation of superoxide anions and the generation of free radicals with H2O2 as substrate. Our results showed that both enzymes contain one copper ion per subunit and have identical dismutation activity. However, the free radical-generating function of the G93A mutant, as measured by the spin trapping method, is enhanced relative to that of the wild-type enzyme, particularly at lower H2O2 concentrations. This is due to a small, but reproducible, decrease in the value of Km for H2O2 for the G93A mutant, while the kcat is identical for both enzymes. Thus, the ALS symptoms observed in G93A transgenic mice are not caused by the reduction of Cu,Zn-SOD activity with the mutant enzyme; rather, it is induced by a gain-of-function, an enhancement of the free radical-generating function. This is consistent with the x-ray crystallographic studies showing the active channel of the FALS mutant is slightly larger than that of the wild-type enzyme; thus, it is more accessible to H2O2. This gain-of-function, in part, may provide an explanation for the association between ALS and Cu,Zn-SOD mutants.
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O reconhecimento das competncias e habilidades necessrias ao exerccio profissional de arquitetos e engenheiros civis brasileiros adquirido em decorrncia das formaes que lhes so oferecidas. No mbito da construo de edifcios, pressupe-se que ambos os profissionais recebem formao equivalente na medida em que os respectivos conselhos lhes atribuem iguais direitos e responsabilidades para exerc-la. Com o objetivo de investigar tal pressuposto, esse trabalho se props a examinar a formao oferecida nesse campo aos profissionais oriundos de duas das principais escolas do pas: da Faculdade de Arquitetura e Urbanismo da USP (FAUUSP) e da Escola Politcnica da USP (EPUSP). Por meio de anlise das estruturas curriculares, de depoimentos docentes coletados em entrevistas, materiais didticos empregados em aulas, registros de aula de estudantes no decorrer do curso e de acompanhamento presencial em disciplinas que versam sobre o assunto, essa pesquisa revelou que as formaes oferecidas pelas duas instituies so profundamente distintas. Na FAUUSP, constatou-se que a formao voltada construo de edifcios corresponde abordagem apenas introdutria dos assuntos, fornecida por meio de disciplinas desarticuladas entre si e em relao s demais disciplinas constantes da estrutura curricular. Na EPUSP, em oposio, o tema inserese em conjunto intimamente articulado de disciplinas, as quais fornecem ao estudante intensa fundamentao cientfica para discusso dos assuntos envolvidos. O trabalho, portanto, refora a ideia, que vem de longa data, sobre a urgncia em se rediscutir a formao oferecida ao estudante de arquitetura e urbanismo na FAUUSP, e principalmente nesse trabalho, no que se refere aos contedos de incumbncia do Grupo de Disciplinas de Construo do Departamento de Tecnologia da Arquitetura da Escola.
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We present an analysis of a pointed 141 ks Chandra high-resolution transmission gratings observation of the Be X-ray emitting star HD110432, a prominent member of the Cas analogs. This observation represents the first high-resolution spectrum taken for this source as well as the longest uninterrupted observation of any Cas analog. The Chandra light curve shows a high variability but its analysis fails to detect any coherent periodicity up to a frequency of 0.05 Hz. Hardness ratio versus intensity analyses demonstrate that the relative contributions of the [1.5-3] , [3-6] , and [6-16] energy bands to the total flux change rapidly in the short term. The analysis of the Chandra High Energy Transmission Grating (HETG) spectrum shows that, to correctly describe the spectrum, three model components are needed. Two of those components are optically thin thermal plasmas of different temperatures (kT 8-9 and 0.2-0.3 keV, respectively) described by the models vmekal or bvapec. The Fe abundance in each of these two components appears equal within the errors and is slightly subsolar with Z 0.75 Z . The bvapec model better describes the Fe L transitions, although it cannot fit well the Na XI Ly line at 10.02 , which appears to be overabundant. Two different models seem to describe well the third component. One possibility is a third hot optically thin thermal plasma at kT = 16-21 keV with an Fe abundance Z 0.3 Z , definitely smaller than for the other two thermal components. Furthermore, the bvapec model describes well the Fe K shell transitions because it accounts for the turbulence broadening of the Fe XXV and Fe XXVI lines with a v turb 1200 km s1. These two lines, contributed mainly by the hot thermal plasma, are significantly wider than the Fe K line whose FWHM < 5 m is not resolved by Chandra. Alternatively, the third component can be described by a power law with a photon index of = 1.56. In either case, the Chandra HETG spectrum establishes that each one of these components must be modified by distinct absorption columns. The analysis of a noncontemporaneous 25 ks Suzaku observation shows the presence of a hard tail extending up to at least 33 keV. The Suzaku spectrum is described with the sum of two components: an optically thin thermal plasma at kT 9 keV and Z 0.74 Z , and a very hot second plasma with kT 33 keV or, alternatively, a power law with photon index of = 1.58. In either case, each one of the two components must be affected by different absorption columns. Therefore, the kT = 8-9 keV component is definitely needed while the nature of the harder emission cannot be unambiguously established with the present data sets. The analysis of the Si XIII and S XV He-like triplets present in the Chandra spectrum points to a very dense (ne ~ 1013 cm3) plasma located either close to the stellar surface (r < 3R *) of the Be star or, alternatively, very close (r ~ 1.5R WD) to the surface of a (hypothetical) white dwarf companion. We argue, however, that the available data support the first scenario.
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The effect of a severe steaming treatment on the physicochemical properties and catalytic performance of H-SAPO-34 molecular sieves during the methanol-to-hydrocarbons (MTH) reaction has been investigated with a combination of scanning transmission X-ray microscopy (STXM), catalytic testing, and bulk characterization techniques, including ammonia temperature programmed desorption and 27Al and 29Si magic angle spinning nuclear magnetic resonance. For this purpose, two samples, namely a calcined and a steamed H-SAPO-34 catalyst powder, have been compared. It has been found that calcined H-SAPO-34 displays a high selectivity towards light olefins, yet shows a poor stability as compared to a zeolite H-ZSM-5 catalyst. Moreover, in situ STXM at the carbon K-edge during the MTH reaction allows construction of nanoscale chemical maps of the hydrocarbon species formed within the H-SAPO-34 aggregates as a function of reaction time and steam post-treatment. It was found that there is an initial preferential formation of coke precursor species within the core of the H-SAPO-34 aggregates. For longer times on stream the formation of the coke precursor species is extended to the outer regions, progressively filling the entire H-SAPO-34 catalyst particle. In contrast, the hydrothermally treated H-SAPO-34 showed similar reaction selectivity, but decreased activity and catalyst stability with respect to its calcined counterpart. These variations in MTH performance are related to a faster and more homogeneous formation of coke precursor species filling up the entire steamed H-SAPO-34 catalyst particle. Finally, the chemical imaging capabilities of the STXM method at the Al and Si K-edge are illustrated by visualizing the silicon islands at the nanoscale before and after steaming H-SAPO-34.
