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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Optimización del proceso de captura de faltas de tránsito de la PNP mediante tecnología móvil

Montes Neira, Jaime J., Spodek Arrue, Vanessa J. January 2015 (has links)
El presente proyecto de tesis está enfocado en optimizar el proceso de captura de faltas de tránsito que regula la Policía Nacional del Perú, dicho proceso necesita de una herramienta que mejore el control de estas infracciones en nuestro país. El problema radica en las innumerables faltas que comete el conductor cuando una autoridad no está presente, además de la poca cultura que existe sobre el respeto a nuestro reglamento de tránsito peruano. Es por ello que proponemos una solución que ayude a mejorar este comportamiento de los infractores, además de promover y mejorar nuestra cultura vial. Dicha solución propone el uso necesario de un dispositivo móvil que le permita a las personas naturales capturar las faltas de tránsito que sucedan a su alrededor. Se opta por esta herramienta móvil ya que la captura debe ser rápida y fácil de utilizar por la mayoría de los peruanos. Este aplicativo móvil incluirá funciones interactivas para el usuario no solo para reportar incidencias de tránsito, sino también para mejorar su cultura vial. Por otro lado servirá de apoyo para tomar decisiones gracias a las estadísticas que se obtendrán a medida que más usuarios utilicen esta herramienta. Por otro lado, la programación ha sido realizada orientada a objetos para un mejor mantenimiento y reusabilidad del aplicativo. Para construir y documentar el aplicativo utilizamos la metodología UML - RUP, la cual nos ayudó a modelar los procesos de negocio y funciones del sistema.
2

Iron and Nickel Hydride Complexes Stabilized by Pyrrole-Based Ligands

Collett, Joel 25 May 2022 (has links)
No description available.
3

Development of a Nanofluid Simulation Platform

Nachit, Jabrane 14 December 2018 (has links)
Nanoluids are colloidal solutions made up of particles of the nanometric scale suspended in a fluid. This type of solution has widespread great interest since the discovery of their particular properties. The Poisson-Nernst Planck system of equations (PNP) is one of the known models for the description of ion transport. This thesis aims to develop a method to solve the PNP equations in space and time for these nanoluids. Additionally, a simulation platform (C++) is developed using an iterative scheme to solve the nonlinear equations resulting from the discretization of the system. After an overview of the literature on the subject, a discussion on the validity of the results obtained through the simulation platform through its comparison with literature and a commercial software package, COMSOL.
4

Thermionic Emission Diffusion Model of InP-based Pnp Heterojunction Bipolar Transistor with Non-Uniform Base Doping

VUMMIDI MURALI, KRISHNA PRASAD 02 September 2003 (has links)
No description available.
5

Evaluación del efecto genotóxico en trabajadores expuestos a Rayos X en el Hospital Nacional Luis N. Sáenz PNP

Infantes Vizcarra, Walter Ivan January 2014 (has links)
El objetivo de esta investigación fue evaluar el efecto genotóxico causado por los Rayos X, en el ADN linfocitario en sangre periférica, utilizando el ensayo cometa como técnica de análisis, en el personal del Servicio de Radiología del Hospital Nacional LUIS N.SAENZ PNP. La población de estudio fue de 40 personas separadas en 2 grupos, el 1ero de 20 trabajadores expuestos a los Rayos X, con un tiempo laboral de exposición de 2-15 años y 16 años a más y de edades entre 20-30 y 31 años a más. El 2do grupo fue el grupo control, formado por personas del mismo centro de trabajo sin exposición a Rayos X. Las muestras de sangre fueron obtenidas por punción venosa en tubos con heparina, de los cuales fueron aislados los linfocitos y asu vez estos fueron colocados en láminas porta objetos con geles, para la realización del ensayo cometa. Las láminas fueron sometidas a lisis alcalina seguida de la corrida electroforética (pH=13), para seguir con la tinción lectura en un microscopio de fluorescencia. El análisis de imágenes se realizó usando el programa informático Komet 4, en el cual se almacenaron los datos recolectados en formato Excel y analizados en el programa estadístico SPSS. Los resultados indicaron que existe un incremento significativo (p<0.05) de daño genotóxico en el 10% de los trabajadores expuestos a los Rayos X y solo el 1% del grupo control. Respecto a la variable de estudio de la edad en el personal expuesto no se encontró resultados significativos. Por el contrario para la variable de tiempo de exposición, los individuos expuestos entre 2 a 15 años presentaron mayor daño celular (Nivel I y II) en relación a los expuestos de 16 a más años que presentaron niveles bajos. Los Rayos X causan un efecto medianamente nocivo en la integridad del genoma teniendo una correlación con los años de exposición del personal que trabaja en el servicio radiología. Los hallazgos confirman la utilidad del ensayo cometa como una herramienta útil para evaluar daño genotóxico y prevenir tempranamente el aparecimiento patologías radio inducidas. The objective of this research was to evaluate the genotoxic effect caused by X-rays in DNA in peripheral blood lymphocytes, using the comet assay and analysis technique, the staff of the National Hospital Radiology LUIS N.SAENZ PNP. The study population was 40 persons separated into 2 groups, the 1st of 20 workers exposed to X-rays, with a working time of exposure 2-15 years and 16 years and over age 20-30 and 31 years later. The 2nd group was the control group, consisting of people from the same workplace without exposure to X-ray Blood samples were obtained by venipuncture into heparinized tubes, which were isolated lymphocytes and assume time these were placed in partment sheets gels, for performing the comet assay. Slides were subjected to alkaline lysis followed by electrophoretic run (pH = 13) to continue reading staining fluorescence microscopy. Image analysis was performed using the Komet 4 software, in which the collected data to Excel and analyzed using the SPSS statistical program was stored. The results indicated that there is a significant increase (p <0.05) of genotoxic damage in 10% of workers exposed to X-rays and only 1% in the control group. With regard to the study variables of age in the exposed staff found no significant results. In contrast to the variable exposure time, exposed individuals between 2-15 years showed greater cell damage (Level I and II) compared to those exposed to more than 16 years had low levels. The X-rays cause a moderately adverse effect on the integrity of having a correlation with years of exposure of personnel working in the radiology service genome. The findings confirm the usefulness of the comet assay as a tool to assess genotoxic damage and prevent early onset pathologies induced within the tool.
6

Copper Hydride Clusters Stabilized by NH-Centered Diphosphines: Synthesis, Structures, and Implications in Catalysis

Ekanayake, Dewmi A. 05 October 2021 (has links)
No description available.
7

Untersuchung der Schnürringarchitektur in Hautbiopsien von Patienten mit Polyneuropathien / Evaluation of nodal architecture of myelinated nerve fibers in skin biopsies of patiens with polyneuropathies

Kilgué, Alexander Pina January 2019 (has links) (PDF)
Polyneuropathien (PNP) können zu einer Reorganisation der nodalen und paranodalen Membranproteine mit in der Folge fehlerhafter Axon-Schwann-Zell-Interaktionen führen. Im Rahmen der Basisdiagnostik einer Polyneuropathie haben sich Hautbiopsien als weniger invasive Ergänzung zur Suralisbiopsie mit einem geringen Nebenwirkungsrisiko entwickelt. Die Morphologie dermaler Nervenfasern lässt sich mittels Immunohistochemie in der Haut gezielt untersuchen. In der vorliegenden Studie wurde die Hypothese überprüft, ob pathologisch auffällige Ranvier-Schnürringe Hinweise auf Unterschiede bei PNP-Subgruppen und Schädigungsmuster liefern. Daneben wurden die Hypothesen überprüft, ob Entzündungszellen an myelinisierten Nervenfasern kolokalisiert nachweisbar sind und ob Hautbiopsien einen zusätzlichen Nutzen zur PNP-Basisdiagnostik liefern. Von 92 Patienten wurden Hautbiopsien von Finger, Ober-und Unterschenkel wurden entnommen, daraus gewonnene myelinisierte Nervenfasern der Haut wurden mittels immunohistochemischer Antikörper-Doppelfärbungen analysiert. Neuropathische Schädigungsformen vom axonalen und demyelinisierenden Typ zeigten keine signifikante Korrelation mit dem Auftreten von verlängerten Ranvier-Schnürringen und der Dispersion charakteristischer paranodaler und nodaler Membranproteine (Neurofascin, Caspr, Pan-Natrium-Kanäle). Kolokalisierte Entzündungszellen an myelinisierten Nervenfasern bei entzündlichen PNP ließen sich nicht nachweisen. PNP-Subgruppen zeigten keine signifikanten Unterschiede in Hinblick auf eine pathologische nodale oder paranodale Organisation. Der Zusatznutzen von Hautbiopsien in der PNP-Basisdiagnostik kann in Bezug auf die vorliegende Arbeit nur eingeschränkt bestätigt werden. Da Fingerbiopsien im Vergleich zu Proben aus Ober- und Unterschenkel eine signifikant höhere Dichte myelinisierter Nervenbündel pro Fläche Dermis aufweisen, wäre es durchaus denkbar, zukünftig primär Fingerbiopsien zu entnehmen um diese auf etwaige pathologische Veränderungen infolge neuropathischer Erkrankungen zu untersuchen. Anamnese, Basisdiagnostik und klinischer Befund erbringen nach wie vor den wichtigsten Beitrag zur PNP-Diagnostik. / Skin biopsy has been suggested as a tool to analyse paranodal and nodal changes of myelinated fibers in demyelinating polyneuropathies. Myelinated fibers of skin biopsies (finger, upper thigh, lower leg) of 92 patients with PNP were obtained and analysed. Immunofluorescence of skin sections with antibodies against Caspr, neurofascin, sodium channels, protein gene product 9.5 and myelin basic protein was performed to analyse the paranodal/nodal architecture. Staining with antibodies against cd 68 and cd 4 was performed to analyse possible co-localisation of inflammation cells and myelinated nerve fibers in patients with inflammatory PNP. There was no significant difference between the subgroups of patients with axonal and demyelinating PNP regarding elongated ranvier nodes or dispersion of characteristical (para-) nodal membrane proteins (Neurofascin, Caspr, Pan-Sodium-Channel). A significant co-localisation of inflammation cells and myelinated nerve fibers in patients with inflammatory PNP was not detectable. PNP subgroups showed no significant differences regarding pathological organisation of (para-)nodal membrane proteins. Skin biopsy may be an appropriate tool to analyse myelinated nerve fibers in patients with PNP, nevertheless anamnesis and clinical examination are the main important tools of PNP diagnostics.
8

Autonomous Close Formation Flight of Small UAVs Using Vision-Based Localization

Darling, Michael B 01 May 2014 (has links) (PDF)
As Unmanned Aerial Vehicles (UAVs) are integrated into the national airspace to comply with the 2012 Federal Aviation Administration Reauthorization Act, new civilian uses for robotic aircraft will come about in addition to the more obvious military applications. One particular area of interest for UAV development is the autonomous cooperative control of multiple UAVs. In this thesis, a decentralized leader-follower control strategy is designed, implemented, and tested from the follower’s perspective using vision-based localization. The tasks of localization and control were carried out with separate processing hardware dedicated to each task. First, software was written to estimate the relative state of a lead UAV in real-time from video captured by a camera on-board the following UAV. The software, written using OpenCV computer vision libraries and executed on an embedded single-board computer, uses the Efficient Perspective-n-Point algorithm to compute the 3-D pose from a set of 2-D image points. High-intensity, red, light emitting diodes (LEDs) were affixed to specific locations on the lead aircraft’s airframe to simplify the task if extracting the 2-D image points from video. Next, the following vehicle was controlled by modifying a commercially available, open source, waypoint-guided autopilot to navigate using the relative state vector provided by the vision software. A custom Hardware-In-Loop (HIL) simulation station was set up and used to derive the required localization update rate for various flight patterns and levels of atmospheric turbulence. HIL simulation showed that it should be possible to maintain formation, with a vehicle separation of 50 ± 6 feet and localization estimates updated at 10 Hz, for a range of flight conditions. Finally, the system was implemented into low-cost remote controlled aircraft and flight tested to demonstrate formation convergence to 65.5 ± 15 feet of separation.
9

Charakterizace fosfatas v rostlinách tabáku (Nicotiana tabacum L.) / Characterization of phosphatases in tobacco plants (Nicotiana tabacum L.)

Růžičková, Kateřina January 2011 (has links)
Phosphateses (EC 3.1.3.x) are a group of enzymes that hydrolyze phosphoesters. That way they affect the energetic metabolism of a cell and its regulation. Phosphatases that dephosphorylate proteins are an integral part of signaling pathways, stress responses and they modulate enzymatic activity. This thesis deals with the study of phosphatases obtained from tobacco leaves (Nicotiana tabacum, L.). Solution of enzymes was prepared by extraction in both acidic and alkaline buffers. Through the use of the chromogenic substrate pNP-phosphate it was determined that there is a higher phosphatase activity in the glycosylated fraction than in the fraction that did not bind to Con A Sepharose. The research of the ions effect on the phosphatase activity has determined that Mg2+ and Ca2+ show positive effect on the phosphatase activity while the effect of Co2+ and Mn2+ is inhibitory. The Zn2+ ions have shown no effect whatsoever. The glycosylated phosphatases also dephosphorylated low-weight-molecular substrates phosphoserine, ATP and glucose-6-phosphate. The research of protein phosphatase activity discovered the affinity to the substrate phosvitin, although neither to casein nor its tryptic cleaves. Detailed experiments have shown that the pH optima for all the substrates lie from pH 5 to 6. Glycosylated phosphatases...
10

In vitro studies of the enzymes involved in fluorometabolite biosynthesis in Streptomyces cattleya

Cross, Stuart M. January 2009 (has links)
Enzymatic fluorination of natural products is extremely rare. Of the 4000 halogenated natural products identified, only 13 possess a fluorine atom. The C-F bond forming enzyme from the soil bacterium, Streptomyces cattleya, remains the only native enzyme to be identified that is capable of such biochemistry. It generates 5’-fluoro-5-deoxyadenosine (5‘-FDA) from S-adenosyl-L-methionine (SAM) and F-. The “fluorinase” is the first committed step toward the biosynthesis of the two fluorometabolites, 4-fluorothreonine and fluoroacetate, via the common intermediate, fluoroacetaldehyde (FAld). The enzymatic steps responsible for the conversion of 5’-FDA to the fluorometabolites remained to be fully characterised when this project began. Previously, a purine nucleoside phosphorylase was identified that was capable of generating 5-fluorodeoxyribose-1-phosphate (5-FDRP) from 5’-FDA. 5-FDRP is subsequently isomerised to 5-fluorodeoxyribulose-1-phosphate (5-FDRulP) by an aldose-ketose isomerase enzyme. Chapter 2 describes the identification of the isomerase gene from the genomic DNA of S. cattleya and the corresponding protein product was capable of generating 5-FDRulP from 5-FDRP. The next intermediate, FAld, is generated from 5-FDRulP by a fuculose aldolase. Attempts to identify the aldolase gene from S. cattleya were unsuccessful, however a putative fuculose aldolase from Streptomyces coelicolor was isolated that could generate FAld from 5-FDRulP, which is described in Chapter 3. Following the identification and over expression of a PLP-dependant transaldolase, which generates 4-fluorothreonine (4-FT) from FAld and L-threonine in S. cattleya, Chapter 4 details the successful in vitro reconstitution of fluorometabolite biosynthesis using five over- expressed enzymes. In Chapter 5, attempts to develop a novel assay for fluorinase activity was explored. The colorimetric detection of L-methionine produced by the fluorinase in a coupled L-amino acid oxidase and horseradish peroxidase assay, leading to the oxidation of a dye substance. This was carried out with interest in developing a high-throughput assay for fluorinase mutants, generated by random mutagenesis, in order to identify those with increased activity. In the event, it proved unsuccessful.

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