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Bálek, Michal. "CO S TÍM? Rekonverze průmyslového areálu, Brno - Obřany." Master's thesis, Vysoké učení technické v Brně. Fakulta architektury, 2011. http://www.nusl.cz/ntk/nusl-215788.
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Báleková, Martina. "CO S TÍM? Rekonverze průmyslového areálu, Brno - Obřany." Master's thesis, Vysoké učení technické v Brně. Fakulta architektury, 2011. http://www.nusl.cz/ntk/nusl-215805.
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My intention to overstep limits and bounds is to renew and create comfortable environment for students and for the local inhabitants. I try to retain values and industrial charakter of spinnig factory.
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Koželouhová, Anna. "CO S TÍM? Rekonverze průmyslového areálu, Brno - Obřany." Master's thesis, Vysoké učení technické v Brně. Fakulta architektury, 2011. http://www.nusl.cz/ntk/nusl-215797.
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The topic of the graduation thesis is the revitalization of the former textile manufacturing complex in the quarter Maloměřice and Obřany of the city of Brno and conversion of its main building, spinning mill, to the school of architecture. Urban design concept is based on several ideas. I tried to involve the complex into the life and urban structure of this part of Brno and to create a possible new center. I also tried to recognize the values and qualities of the area as a whole and of its individual components. I created zones, characterized by different interactions with the neighborhood. By the entrance into the area I place an object called “gate”, which should draw the attention of passers-by. It clearly guides to enter the island and later the school building. The central part of the island is cleaned from the later extensions and a new foreground of entry to school is formed there. This zone, which continues to the north over the old mill-race between the neighboring buildings, is public, communicates, but is clearly defined and has its own inner life. Third, semi-private area is a residential waterfront of the mill-race with the existing balcony-access house and a new housing for students. The fourth area is a public park, detached from the school entrance courtyard by the block of trees and connected to the village by a new foot bridge. The architectural design of the spinning-mill conversion is based on the concept of inserting new objects into existing autonomous structure of the house. The purity of the building and support structures is preserved. Through the insulation of the inserted objects the thermal comfort is achieved. In the building I leave free space, which is cut through all floors throughout the four chimneys of the stairs, sanitary facilities and installations. Into the individual fields of the concrete-frame construction I put rectangular boxes of different functions - classrooms, studios and offices. These are connected with the chimneys via electrical and ventilation lines. The existing building façade remains unchanged, it defines the internal space, it is a connecting element, rather than separating.
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Kuruc, Adam. "PERLA Ústí nad Orlicí." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2016. http://www.nusl.cz/ntk/nusl-354973.
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The theme of the thesis is a study of the project of „brownfield“ conversion of ex used cotton factory hall PERLA, Bavlnářské závody, A.s in Ústí nad Orlicí city. Prepartory work has dealt whole complex. Thesis follows up only study of a elected part. There are demolished, maintained and brand new objects with underground level garages. Urban and mass solution creates a complex of buildings with a city-forming character and allows going follow the area.
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Santos, João Pedro Pires dos. "Comportamento online dos portugueses e identificação dos factores de conversão." Master's thesis, Instituto Superior de Economia e Gestão, 2018. http://hdl.handle.net/10400.5/17287.
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Mestrado em Econometria Aplicada e PrevisãoO presente estudo tem como objectivo a determinação de indicadores avançados que permitam identificar indivíduos susceptíveis de se converterem a um sítio online relativo aos sectores da banca e seguros. Para tal, a partir de uma amostra que contém informação comportamental online de um painel de utilizadores portugueses, foi feita uma análise descritiva aos dados, seguida da estimação de dois modelos de regressão logística respeitante a cada sector alvo de análise. A análise descritiva aos dados demonstra que variáveis demográficas, tais como idade, região, sexo e situação laboral do indivíduo, foram relevantes na distinção dos indivíduos convertidos e não convertidos. Do primeiro modelo logit estimado, relativo à banca, retiramos o motor de busca e a combinação de indicadores comportamentais com características demográficas, como as variáveis que melhor prevêem a conversão de um indivíduo no sector. Jovens com idades entre os 18 e 30 anos, recentemente pais, que passam muito tempo em casa e não estão habituados à internet, constituem um dos perfis mais destacados na probabilidade de ocorrência do evento conversão em banca. Relativamente à segunda regressão estimada, para os seguros, conclui-se que o último clique antes da conversão é o mais relevante. Um indivíduo é mais passível de se converter ao sector de seguros, partindo directamente da página de uma grande empresa. Este fenómeno está implicitamente relacionado com os funcionários que beneficiam de seguro de saúde de uma dada empresa.
The present study's goal is identifying the factors that most explain the conversion of internet users in a website related to the banking and insurance sectors. From a sample containing online behaviour data about a panel of portuguese users, a descriptive analysis was done, followed by the estimation of two logistic regression models for each sector of analysis. The descriptive analysis of data showed that demographic variables such as age, sex, and the individual's work situation, were relevant to distinguish between converted and unconverted individuals. The first estimated logit model, relative to banking, points the use of search engine and a combination of behavioral indicators with demographic characteristics, as the variables that best explains the conversion in the sector. For the second logistic regression, about the insurance sector, we conclude the last click immediately before the conversion, is the most relevant to the event. There are bigger odds an internet user gets converted in the insurance sector, by jumping directly from a website regarded to a big corporation. This phenomenon is linked to employees that benefits from a health insurance service, provided by the corporation.
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Lajtkepová, Lenka. "PERLA Ústí nad Orlicí." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2016. http://www.nusl.cz/ntk/nusl-354979.
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This diploma thesis is built on prediploma project, whose aim was to create a strategy for converting of ground of textile factory Perla in Usti nad Orlici. During prediploma project functional content of the whole area was designed, for diploma thesis it was chosen part of this territory and it was processed in detail. Specifically, it was chosen the southwestern part of the area situated around a factory smokestack. Partly, there is a new use of existing buildings and partly there are designed new objects. Preserved buildings will be newly used as a museum, gallery, IQ center, formal hall, shops and offices. All new buildings in the selected area will be used for commercial purposes, namely for shops, offices, services and a cafeteria. Important city-forming elements are two squares: one smaller around the chimney, which is intimate, and the second square, which is larger, so there is enough room for holding various social events.
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Cyrnerová, Jana. "MOSILANA BRNO." Master's thesis, Vysoké učení technické v Brně. Fakulta architektury, 2014. http://www.nusl.cz/ntk/nusl-216067.
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Subject of master thesis is urban nad architecture study of former textile factory area and land along the street Křenová. The main theme of the solution is integration and rehabilitation of the contemporary building into organism of the city and susceptible addition of new masses which is based on the principles of compact city. Emphasis is also put on increasing throughput and quality of public spaces, which is missing nowadays. In detail I am focused on new buildings – the residential house on the green parking platform, row houses along the river Ponávka and alternative conversion of fomer Dye House into Mother Center. The aim is to propose some alternative to currently inappropriate land use and invention based on the Regional Plan.
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Ambrosová, Katarína. "MERINA 2.0." Master's thesis, Vysoké učení technické v Brně. Fakulta architektury, 2019. http://www.nusl.cz/ntk/nusl-400694.
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The aim is to create a vision for the future development of a problematic brownfield near the city center of Trenčín. The territory of former MERINO textile factory next to the military barracks, park and railway station is for long neglected, but still valuable in terms of urbanism, industrial heritage and new urban potential. The project will focus on the realistic spatial restructuring of the area and on the search for its new functional content.
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Kocourek, Tomáš. "CO S TÍM? Rekonverze průmyslového areálu, Brno - Obřany." Master's thesis, Vysoké učení technické v Brně. Fakulta architektury, 2011. http://www.nusl.cz/ntk/nusl-215800.
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The name of the project prompts the problems of legacy of industrial premises. The goal of my work was to consider, how to use the buildings in the premises in Obřany, Brno. The aim was on the most important object – former building of Essler’s spinning factory, which was supposed to be turned into school of architecture for one hundred students in two school years. The work aims on connection of the area with the city. It solves objects themselves, tries to find accurate usage of them, for example commersial premises, student housing and so on. All this is united with the concept of „union“, which goes throught the whole area and tries to create simple a most of all plesant public places. The school – building of former spinning factory – disclose it’s strenght in it‘s open space, when the whole structure of the building is visible. I came from this conviction into my project, that agreed with my image of open shool. I wanted to design a school, where students could create together, where they would have review of the whole space, about other students. Tuitions would become public matter, where everybody could join.
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Horáková, Terezie. "Muzeum průmyslového dědictví v areálu bývalé textilní továrny v Prostějově." Master's thesis, Vysoké učení technické v Brně. Fakulta architektury, 2014. http://www.nusl.cz/ntk/nusl-216062.
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The factory premises of the former factory OP Prostějov is the challenge for the future generations how to appraise today unused buildings which were build in 1950's. My design is counting with formation of new part of town, which disposes with centralizing the town-hall administration in one place allowing simple moving between individual authorities. Next there is designed the habitation as the small flats for old people and also big flats with interesting view. In some buildings there is designed the business incubator and in other building there is even the school. There are all facilities, services and leisure activities provided in the area. The Museum of Industrial Heritage is located in the middle of all events. It has three parts - exhibition, auditorium and deposit with administration. The old heating plant nearby is used as library and médiatheque with archives in connection with the museum. Shops, restaurants and other services are placed around.
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JÃnior, Josà Ailton LeÃo Barboza. "A Double boost converter with PFC and series/parallel input connection for uninterrupted power system." Universidade Federal do CearÃ, 2012. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=16257.
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fator de potÃncia e recurso para operar com dois valores de tensÃo de entrada. O mesmo à aplicÃvel a sistemas ininterruptos de energia do tipo dupla conversÃo ou on-line com caracterÃsticas de tensÃo de entrada bivolt (110 Vca e 220 Vca) e desta maneira à descartada a
utilizaÃÃo de um autotransformador com seletor de tensÃo. O conversor em estudo à composto por dois conversores CA-CC boost clÃssicos, em que, para uma tensÃo de entrada de 110 Vca as entradas sÃo conectadas em paralelo e para uma tensÃo de entrada de 220 Vca as entradas sÃo conectadas em sÃrie. A ideia à fazer com que se tenha uma divisÃo equilibrada na entrada de cada conversor quando a tensÃo da rede elÃtrica for 220 Vca. Assim cada conversor boost
clÃssico recebe metade da tensÃo total de alimentaÃÃo do conversor proposto. A estratÃgia de controle à baseada no controle por modo corrente mÃdia aplicada a ambos os conversores para proporcionar a correÃÃo do fator de potÃncia e a regulaÃÃo da tensÃo de saÃda. Para verificar o estudo teÃrico foi desenvolvido o projeto do circuito de potÃncia e controle validando atravÃs de resultados de simulaÃÃo e experimentais para um protÃtipo de 2,4 kW. Para a conexÃo paralelo e sÃrie das entradas, os resultados obtidos foram satisfatÃrios e o conversor operou adequadamente.This work presents a study of a Double Boost AC-DC Converter with power factor correction and dual input voltage operation capability via a selector switch. Such converter can be applied to on-line uninterruptible power supplies with dual voltage input characteristics, this way avoiding the usage of a low frequency autotransformer. The studied structure is composed by two AC-DC classical boost converters, in which for input voltage of 110 Vac both its inputs are connected in parallel, and, for 220 Vac, they are connected in series. The control strategy is based in the average current mode control applied to both converters, in order to provide the power factor correction and output voltage regulation. Simulation and experimental results for 2.4 kW are presented, and so are validate the theoretical study and design. Connecting the inputs in parallel and series, the results were satisfactory and the converter operated properly.
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Collins, Philip J. "Common factors which accompany adolescent conversions." Theological Research Exchange Network (TREN), 1993. http://www.tren.com.
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Cardoso, José Ribamar de Abreu. "Uso do agregado de entulho da construção civil de Manaus - AM para obtenção de bloco de argamassa celular." Universidade Tecnológica Federal do Paraná, 2010. http://repositorio.utfpr.edu.br/jspui/handle/1/184.
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Programa de mestrado interinstitucional UTFPR/IFAM - MINTER/MANAUSNa construção civil tem-se procurado mecanismos por meio de novas técnicas que possibilitem viabilizar a sustentabilidade dessa atividade produtiva, espeitando às questões ambientais e a tendência de escassez dos recursos naturais. A indústria da construção civil tem buscado na reciclagem dos resíduos de construção e demolição (RCD) uma forma de atenuar o impacto ambiental e buscar uma fonte alternativa de matéria-prima. Associado a essa preocupação, grandes centros consumidores da região Amazônica, como Manaus, utilizam agregados para produção de concretos e argamassas minerados dos leitos dos rios e trazidos de grandes distâncias. O presente trabalho tem como objetivo estudar a obtenção de blocos de argamassa celular para alvenarias, utilizando agregados de RCD em substituição aos agregados convencionais. Os blocos de argamassa celular são largamente utilizados na Europa como elementos de alvenaria devido à capacidade de isolamento térmico e acústico, parâmetros esse de grande relevância para um elemento construtivo também em regiões de clima quente. Em Manaus existem empresas que constroem habitações com argamassa celular monolítica, ou seja, todas as alvenarias da residência são moldadas em uma única etapa. Assim, após obtenção e caracterização da fração cinza de RCD, foi utilizada uma composição comercial de argamassa celular para analisar a substituição dos agregados alternativos pelo RCD. Com isso buscou-se também obter uma dosagem mais econômica, com resistência mecânica exigida pela norma brasileira para blocos e minimizar o impacto ambiental de argamassas celulares convencionais. Os resultados técnicos foram favoráveis, com potencial para consumir agregados de RCD, contribuindo assim na gestão ambiental desse resíduo da construção civil.
In building construction, we have searched for mechanisms through new technologies which enable the sustainability of this productive activity, respecting the environmental issues and the shortage of natural products. Civil construction industry has searched for construction and demolition recycling (RCD) as a way of mitigating the environmental impact and a way of seeking for an alternative source of raw material. Associated with this concern, large consumer centers in the Amazon region, such as Manaus, have been using aggregates to produce concrete and mortar mined from the riverbeds and brought from great distances. This work aims to study the acquisition of blocks of masonry mortar cell, using clusters of RCD as a substitute for conventional aggregate. The blocks of mortar cell are widely used in Europe as masonry units due to their thermal and acoustic isolation abilities, which constitute very important parameters for building elements in warm climates. In Manaus, there are companies that build houses with mortar and monolithic cells, i.e., all the walls of the residence are molded in a single step. Thus, after obtaining and characterizing the ash fraction of RCD, we used a commercial composition of mortar cell to analyze the substitution of the alternative aggregates by RCD. With this procedure we searched to obtain a more economic dosage with the strength required by the Brazilian standard blocks and minimize the environmental impact of conventional mortar cells. The technique results were positive, with the potential of consuming RCD aggregates, thus contributing to the environmental management of this civil construction waste.
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Wiemeyer, Marguerite Ruth. "Factors Influencing Interns' Conversion to Full-Time Employment." Thesis, The University of Arizona, 2014. http://hdl.handle.net/10150/322085.
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Wooten, Hasani Omar. "Calculation of internal dose conversion factors for selected spallation products." Thesis, Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/17247.
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Kalpaktsoglou, Dimitrios. "Power factor correction for stand-alone wave energy conversion buoys." Thesis, University of Newcastle Upon Tyne, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.519591.
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Zhao, Qun. "Performance Improvement of Power Conversion by Utilizing Coupled Inductors." Diss., Virginia Tech, 2003. http://hdl.handle.net/10919/26224.
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This dissertation presents the derivation, analysis and application issues of advanced topologies with coupled inductors. The proposed innovative solutions can achieve significant performance improvement compared to the state-of-the-art technology.
New applications call for high-efficiency high step-up DC-DC converters. The basic topologies suffer from extreme duty ratios and severe rectifier reverse recovery. Utilizing coupled inductor is a simple solution to avoid extreme duty ratios, but the leakage inductance associated with the coupled inductor induces severe voltage stress and loss. An innovative solution is proposed featuring with efficient leakage energy recovery and alleviated rectifier reverse recovery. Impressive efficiency improvement is achieved with a simple topology structure. The coupled inductor switching cell is identified. Topology variations and evaluations are also addressed.
The concept that utilizes coupled inductors to alleviate rectifier reverse recovery is then extended, and new topologies suitable for other applications are generated. The proposed concept is demonstrated to solve the severe rectifier reverse recovery that occurs in continuous current mode (CCM) boost converters. Significant profile reduction and power density improvement can be achieved in front-end CCM power factor correction (PFC) boost converters, which are the overwhelmingly choice for use in telecommunications and server applications.
This dissertation also proposes topologies to realize the single-stage parallel PFC by utilizing coupled inductors. Compared to the state-of-the-art single-stage PFC converters, the proposed topologies introduce a new power flow pattern that minimizes the bulk-capacitor voltage stress and the switch current stress.Ph. D.
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Cueva, Flores Dany Richar. "Factores predictivos de conversión en colecistectomía laparascópica." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2011. https://hdl.handle.net/20.500.12672/15182.
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Identifica los factores predictivos de conversión en CL. Es un estudio retrospectivo tipo casos y controles basándonos en las historias clínicas y reportes operatorios de 2596 pacientes sometidos a CL desde enero del 2004 hasta enero del 2009 en el Hospital Nacional Dos de Mayo. Se formaron dos grupos, el primero llamado casos conformado por pacientes sometidos a CL convertida y el segundo llamado control conformado por pacientes en los que se realizó CL satisfactoriamente. Se analizaron 16 variables preoperatorias demográficas, clínicas, de laboratorio y ecográficas mediante el análisis univariado y multivariado de regresión logística para identificar factores predictivos independientes de conversión en CL. Del 126 (4.85%) colecistectomías laparoscópicas fueron convertidas. Las principales causas de conversión fueron la presencia de adherencias (36.51 %), dificultad para identificar el triángulo de Calot (26.19 %), vesícula gangrenada (13.49 %), sangrado (6.35%), coledocolitiasis (5.56%), sospecha o lesión de la vía biliar (4.76%). El análisis multivariado identificó como factores predictivos independientes de conversión a la colecistitis aguda (OR =3.12; p= 0.0033), leucocitosis (OR =3.69; p= 0.0006), elevación de bilirrubinas totales (OR =3.39; p= 0.0015) y el grosor de la pared vesicular determinado por ultrasonido ≥ 4 mm (OR =4.76; p= 0.0001). Conclusiones. La conversión a colecistectomía abierta se puede predecir basándonos en variables disponibles preoperatoriamente. La colecistitis aguda, leucocitosis, elevación de bilirrubinas totales y el engrosamiento de la pared vesicular están probablemente asociados a conversión. Identificar estos factores ayuda al planeamiento quirúrgico y al asesoramiento preoperatorio de los pacientes sometidos a colecistectomía laparoscópica.Trabajo académico
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Lüthi, Nora. "Acute partial transverse myelitis : risk factors for conversion to multiple sclerosis /." Bern : [s.n.], 2008. http://opac.nebis.ch/cgi-bin/showAbstract.pl?sys=000277053.
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Tshiningayamwe, Sirkka Alina Nambashu. "Exploring functionings and conversion factors in biodiversity teacher professional learning communities." Thesis, Rhodes University, 2016. http://hdl.handle.net/10962/d1021313.
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The study explores the conversion factors, functionings (valued beings and doings), agency and structures in Professional Learning Communities (PLCs) for Life Sciences teachers’ biodiversity knowledge. The teachers’ valued beings and doings as well as conversion factors associated with these beings and doings were discussed within the conceptual framework of the capability approach using three PLCs in South Africa. Two PLCs were in the Eastern Cape Province (Grahamstown and Idutywa district), and one PLC was in the Western Cape (Cape Town) province. The PLCs involved in this study were course initiated and were positioned in the Fundisa for Change national teacher education programme. Fundisa for Change is a partnership programme that aims to enhance transformative environmental learning through teacher education. To illuminate constrained capabilities and how and to what extent the Life Sciences teachers’ empirical actions are related to these, the concepts of the capability approach were underlaboured with critical realism’s causal view of human action. A critical realist theory of causation was useful in explaining how the teachers’ valued beings and doings, conversion factors and capability sets can be partly accounted for via an understanding of underlying mechanisms that are generative of events and empirical experience. The study used a qualitative case study research methodology. Interviews, questionnaires, observations (of PLC activities), document reviews (of teachers’ portfolios of evidence, Fundisa for Change implementation plan, evaluation forms and resources materials, and policy documents) and reflection tools were used to collect data. Using the critical realism modes of inference (induction, abduction and retroduction), the data was analysed in two phases. Phase one analysis was primarily inductive and used thick descriptions (mainly in the form of quotes) to present and discuss the teachers’ valued beings and doings and associated conversion factors in the PLCs. This phase of analysis was abductive. The study reported four main functionings valued by teachers: subject content knowledge, teaching practices, assessment practices, and use of teaching and learning support materials. These valued functionings were discussed in light of the beings and doings in the PLCs and the underlying mechanisms related to teachers’ biodiversity teaching. Conversion factors that were associated with the teachers’ valued beings and doings in the PLCs were discussed in line with capability approach’s environmental, social and personal conversion factors. The study found that most of the conversion factors within the PLCs and the Fundisa for Change professional development programme (good facilitation, collaborative learning space, site where PLC activities happened, individual teachers’ capabilities, teaching and learning support materials and policy documents) were enablers to the teachers’ capabilities for biodiversity teaching, and thus enhanced teachers’ knowledge for biodiversity teaching. The study further found that teachers realised some of their achieved functionings in their actual teaching of biodiversity content in the Life Sciences curriculum, and that factors such as lack of resources, large class sizes, learners’ abilities and lack of interest among some teachers were amongst the factors that constrained teachers’ realisation of their achieved functionings in the PLCs. The study therefore revealed that if professional development programmes take account of underlying mechanisms and respond to teachers’ capabilities i.e. their valued functionings for biodiversity teaching in the Life Sciences curriculum, the professional development programmes can be an important conversion factor that enables the expansion of teachers’ capabilities (especially their biodiversity knowledge, pedagogical and assessment practice but also other capabilities) in ways that have the potential to reshape teachers’ classroom practices related to the teaching of biodiversity.
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Lalander, Emilia, Mårten Grabbe, and Mats Leijon. "On the velocity distribution for hydro-kinetic energy conversion from tidal currents and rivers." Uppsala universitet, Elektricitetslära, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-195499.
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Tidal currents and rivers are promising sources of renewable energy given that suitable turbines for kinetic energy conversion are developed. To be economically and technically feasible, a velocity distribution that can give a high degree of utilization (or capacity factor), while the ratio of maximum to rated velocity is low would be preferable. The rated velocity is defined as the velocity at which rated power is achieved. Despite many attempts to estimate the resource, however, reports on the possible degree of utilisation from tidal currents and rivers are scarce. In this paper the velocity distribution from a number of regulated rivers, unregulated rivers and tidal currents have been analysed regarding the degree of utilisation, the fraction of converted energy and the ratio of maximum to rated velocity. Two methods have been used for choosing the rated velocity; one aiming at a high fraction of converted energy and one aiming at a high degree of utilisation. Using the first method, with a rated velocity close to the maximum velocity, it is unlikely that the turbine will reach the cut-out velocity. This results in, on average, a degree of utilisation of 23% for regulated rivers, 19% for unregulated rivers and 17% for tidal currents while converting roughly 30-40% of the kinetic energy. Choosing a rated velocity closer to the mean velocity resulted in, on average, a degree of utilisation of 57% for regulated rivers, 52% for unregulated rivers and 45% for tidal currents. The ratio of maximum to rated velocity would still be no higher than 2.0 for regulated rivers, 1.2 for unregulated rivers and 1.6 for tidal currents. This implies that the velocity distribution of both rivers and tidal currents is promising for kinetic energy conversion. These results, however, do not include weather related effects or extreme velocities such as the 50-year velocity. A velocity factor is introduced to describe what degree of utilisation can be expected at a site. The velocity factor is defined as the ratio U-max/U-rate at the desired degree of utilisation, and serves as an early indicator of the suitability of a site.
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Sazak, Bekir Sami. "A new unity power factor quasi-resonant induction heater." Thesis, University of South Wales, 1997. https://pure.southwales.ac.uk/en/studentthesis/a-new-unity-power-factor-quasiresonant-induction-heater(f2b62fc5-7178-47c3-9da4-4a96b91ea45a).html.
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This thesis reports an investigation into the design of converters for induction heating systems based upon resonant switch mode power converter techniques. The proposed three phase unity power factor induction heating system consists of two stages of power conversions. The important requirements for each stage of the power conversion of a typical induction heating system working from a three-phase supply are identified. A wide range of power converters which fulfil these requirements are compared and evaluated. From the evaluation, the most applicable converter topologies are selected. Each selected converter class is investigated in great detail to outline their advantages and disadvantages. The first stage consists of a push-pull buck converter connected to a unity power factor rectifier stage. This stage converts the three phase AC mains supply to a required DC value. The second stage, which converters the DC into AC is a single ended resonant inverter system. Analysis of the converters has been made and the design procedure has been formulated. The design procedure allows a strenuous design of each resonant converter for particular converter applications. The final converter design has been simulated using the circuit simulation software packages Design Architect and Accusim to verify the results of analysis. The most important design and construction achievements can be summarised as follows: I A novel push-pull buck quasi-resonant converter with a three-phase rectifier stage has been built and tested. At its maximum operating frequency of 40kHz, the prototype converter delivers an output power of 500W. The converter draws nearly sinusoidal currents from the three-phase mains supply and has an input power factor approaching unity. A secondary stage resonant converter provides AC for the induction heater coil. This AC current flowing in the induction coil creates an alternating electromagnetic field for the workpiece. An induction heating coil has been designed and built by using electrical equivalent coil design method. A novel control strategy was developed to provide output power control. Both converter and inverter stage of the system are operated in the zero-current switching condition. The use of this technique allows higher switching frequencies and provides low switching losses. The full design details are presented along with simulation and practical results. The simulation and practical performance results presented show good correlation with theoretical predictions.
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URIBE, Francisco Jose Buelvas. "Análise operacional de um sistema fotovoltaico com alta concentração de 10kWp interligado à rede." Universidade Federal de Pernambuco, 2015. https://repositorio.ufpe.br/handle/123456789/17483.
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CNPq
No presente estudo foi avaliado o comportamento da eficiência na geração de energia, desempenho e influência sobre os parâmetros de operação da rede elétrica de um Sistema Fotovoltaico de Alta Concentração (HCPV- High Concentrating Photovoltaics) interligado à rede em condições reais de operação. O sistema foi instalado no Departamento de Energia Nuclear (DEN) da UFPE. Os ensaios experimentais, realizados com medições do recurso solar incidente no local de instalação, permitiram estabelecer o comportamento da energia gerada em condições instantâneas, médias diárias e mensais. O sistema HCPV foi comparado com um sistema convencional de Silício policristalino (Si-P), de capacidade similar, operando nas mesmas condições meteorológicas durante o mesmo período. Ao longo do período de análise verificou-se que devido ao alto índice de nebulosidade, o recurso solar em Recife não promove condições vantajosas para o aproveitamento da elevada eficiência de conversão do sistema HCPV, em média 22%, chegando a níveis de 26%. Quando comparado com o sistema Si-P, embora o sistema HCPV apresente uma eficiência maior, o mesmo gerou, em Recife, 22% a menos de energia que o sistema Si-P, devido à capacidade do Si-P de aproveitar a irradiância global, em média 40% maior que a direta normal vista pelo sistema HCPV. Para realizar uma comparação entre o desempenho e a energia gerada pelos dois sistemas foi utilizado o índice de desempenho (PR - Performance Ratio) e o fator de capacidade. Uma simulação com base nos resultados experimentais, comparando os dois sistemas, foi realizada para as cidades de Petrolina (PE), São Martinho (RS) e Barra (BA). Verificou-se que o sistema HCPV é capaz de gerar 9% a mais de energia em Petrolina que o Si-P. Os valores obtidos para São Martinho e Barra foram 22% e 32% superiores, respectivamente. Os resultados mostram que o sistema HCPV pode vir a ser viável para as localidades, com elevados níveis de irradiância direta. Foi possível verificar que devido à pequena potência instalada do sistema HCPV (10 kWp) - comparada ao nível de consumo de energia do DEN - não houve influência apreciável sobre os parâmetros de operação da rede elétrica.
This work presents an analysis of the power generation, efficiency’s behavior, performance and influence on the electrical grid of a High Concentrating Photovoltaic system (HCPV) connected to the grid operating under real conditions. The system was installed at Nuclear Energy Department (DEN) - UFPE. The experimental tests, with measurements of the solar radiation resources at the installation site, allowed establishing the behavior of generated energy in instantaneous conditions, daily and monthly averages. The HCPV system was compared with a conventional polysilicon (Si-P) system, similarly capacity, operating under the same weather conditions over the same period. Along the analysis period, it was found that due to the high amount of cloud cover, the solar resource in Recife does not promote favorable conditions to take advantage of the high conversion efficiency of the HCPV system, with average of 22%, reaching levels of 26%. When compared with the Si-P system, although the HCPV presents higher efficiency, it has generated, in Recife, 22% less energy than the Si-P system due to the ability of the Si-P to take advantage of the global irradiance, in average 40% higher than the direct normal irradiance “view” by the HCPV system. Making a comparison of the performance and of the energy generated by the two systems we used the performance ratio (PR - Performance Ratio) and capacity factor. A simulation based on the experimental results, comparing the systems, was held for the cities of Petrolina (PE), St. Martin (RS) and Barra (BA). It was found that the HCPV system is capable to generate 9% more energy in Petrolina than the Si-P. The values obtained for St. Martin and Barra were 22% and 32% larger, respectively. The results show that the HCPV system could be viable for locations with high levels of direct irradiance. The analysis of the behavior of the HCPV system connected to electrical grid shows that due to the small installed capacity of HCPV system (10kWp) - compared to the level of the Nuclear Energy Department power consumption - no appreciable influence on the operating parameters of the electric grid could be detected.
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Ruetz, Tyson Joel. "Smad2/3 potentiate cell identity conversions with master transcription factors." Thesis, University of Edinburgh, 2016. http://hdl.handle.net/1842/21703.
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The exogenous expression of master transcription factors (TFs) to drive cell identity changes is an exciting and powerful approach to cell and tissue engineering. Yet, the generation of desired cell types is often plagued by inefficiency and inability to produce mature cell types. Through investigations of the molecular mechanisms of induced pluripotent stem cell (iPSC) generation, I discovered that expression of constitutively active Smad2/3 (Smad2CA/3CA), together with the Yamanaka factors, could dramatically improve the efficiency of reprogramming. Mechanistically, SMAD3 interacted with both co-activators and reprogramming factors, bridging their interaction during reprogramming. Because SMAD2/3 interact with a multitude of master TFs in different cell types, I tested the conversions of B cells to macrophages, myoblasts to adipocytes, and human fibroblasts to neurons. Remarkably, each conversion system was markedly enhanced when the master TFs were co-expressed with Smad3CA. These results revealed the existence of shared molecular mechanisms underlying diverse TF-mediated cellular conversions, and demonstrated SMAD2/3 as a widely applicable cofactor that potentiates the generation of diverse cell types with profound efficiency and maturity.
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Galante, Chiara [Verfasser]. "Factors determining competence for in vivo glia-to-neuron conversion / Chiara Galante." Mainz : Universitätsbibliothek Mainz, 2019. http://d-nb.info/1199625086/34.
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Pelayo, Vergara Raúl. "Factores pronósticos no radiológicos de conversión a esclerosis múltiple y discapacidad de los síndromes clínicamente aislados." Doctoral thesis, Universitat Autònoma de Barcelona, 2016. http://hdl.handle.net/10803/381081.
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La resonancia magnética (RM) se ha convertido en la herramienta básica para el diagnóstico de la esclerosis múltiple (EM) y establecer el riesgo de conversión a la misma y de discapacidad de los síndromes clínicamente aislados (SCA). No obstante, pueden existir otros factores (clínicos, neurofisiológicos o marcadores serológicos y de líquido cefalorraquídeo) con capacidad potencial de aumentar su capacidad predictiva .
La presente tesis se basa en un compendio de tres artículos en los que se estudian algunos de estos factores no radiológicos, incidiendo en tres ejemplos: uno de la esfera clínica, otro de la neurofisiológica y finalmente en la de los marcadores serológicos.
En el primero de los artículos se evalúa la frecuencia de los síndromes hemisféricos y polirregionales en una cohorte de 320 SCA consecutivos: doce de los mismos fueron clasificados como polirregionales y 6 como hemisféricos. Aunque la baja frecuencia de estas formas de presentación hacen difícil un análisis estadístico adecuado, aparentemente su comportamiento en cuanto al riesgo de conversión a EM parece similar al de otras formas más comunes como las mielitis o los síndromes de fosa posterior (el grupo de neuritis óptica mostró una tasa de conversión menor). Finalmente se realiza una disertación sobre la falta de acuerdo en la definición de estos SCA atípicos, enfatizándose la necesidad de un consenso.
En el siguiente artículo se intenta esclarecer si los potenciales evocados multimodales (PEMMs) añaden información a la RM en los SCA en cuanto a riesgo de conversión a EM y de discapacidad a medio plazo. Se analizó para ello una cohorte de 245 pacientes a los que se les habían realizado potenciales evocados visuales, somatoestésicos y auditivos de tronco. Posteriormente se evaluó el tiempo transcurrido hasta el segundo brote y en llegar a una puntuación en la escala EDSS de 3,0. Con una media de seguimiento de 76 meses, 71 pacientes (29%) mostraron tres PEs normales, 115 (47%) tenían uno alterado, 40 (16%) dos y 19 (8%) los tres. Al analizar los resultados, los PEMMs finalmente no añadían información a los hallazgos de la RM craneal en cuanto a la conversión en EM clínicamente definida (EMCD). No obstante, la presencia de los 3 PEs alterados suponían un riesgo mayor de desarrollar discapacidad moderada (EDSS 3,0), independientemente de los hallazgos de la RM (hazard ratio 7,0 (0,7-69,6)). En resumen, podemos concluir que la presencia de 3 PEs alterados puede ayudarnos a identificar pacientes con un SCA con alto riesgo en desarrollar discapacidad, de forma independiente a los hallazgos radiológicos. No obstante, su utilidad se ve limitada por el bajo porcentaje de pacientes con un SCA que presentaron de forma basal una anormalidad en los 3 PEs.
El artículo anexo es un intento de reproducir los hallazgo de un estudio (Berger et al, N Engl J Med 2003) en el que se concluía que la presencia de anticuerpos anti-MOG y anti-MBP en suero de pacientes con un SCA se relacionaba con un mayor riesgo en la aparición de un segundo brote. Se buscó replicar estos resultados en una cohorte mayor, utilizando la misma técnica de detección de los anticuerpos y con el mismo criterio de selección de los pacientes que en el estudio origen. Finalmente 114 pacientes fueron incluidos en el estudio, con una media de seguimiento de 47 meses. Como conclusión, los pacientes con anticuerpos antimielina positivos no presentaron más riesgo de conversión a EMCD que aquellos sin la presencia de los mismos, por lo que no queda demostrado que la presencia de dichos anticuerpos sea un marcador de riesgo de conversión a EMCD.Magnetic resonance imaging (MRI) has become the basic tool for the diagnosis of multiple sclerosis (MS) and to establish the risk of conversion to MS and disability of the clinically isolated syndromes (CIS). However, other factors (clinical, neurophysiological and serological or cerebrospinal fluid markers) could have the potential capacity to increase its predictive capacity. This thesis is based on a compendium of three articles on some of these non-radiological factors are studied, focusing on three examples: one of the clinical sphere, another neurophysiological and finally in a serological marker. In the first article, the frequency of the polyregional and hemispheric syndromes are evaluated in a cohort of 320 consecutive SCA: twelve of them were classified as polyregional and 6 as hemispheric. Although the low frequency of these presentations makes it difficult to an appropriate statistical analysis, their risk of conversion to MS seems similar to other more common forms such as myelitis or posterior fossa syndromes (the group of optic neuritis he showed a lower rate of conversion). Finally, a dissertation on the lack of agreement on the definition of these atypical SCA is made, emphasizing the need for consensus. The following article attempts to clarify whether multimodal evoked potentials (MMEPs) add information to MRI in SCA in risk of conversion to MS and medium term disability. A cohort of 245 patients who had undergone visual evoked, somatosensory and auditory brain stem potentials was analysed. Subsequently, time until the second relapse and to reach a score of 3.0 EDSS was evaluated. With a mean follow up of 76 months, 71 patients (29%) showed three normal PEs, 115 (47%) had one altered, 40 (16%) two and 19 (8%) three. Finally PEMMs did not add information to the brain MRI findings concerning the conversion into clinically definite MS (CDMS). However, the presence of three altered PEs involved a greater risk of developing moderate disability (EDSS 3.0), regardless of the MRI findings (hazard ratio 7.0 (0.7 to 69.6)). In summary, we can conclude that the presence of 3 altered PEs can help us identify CIS patients with a high risk of developing disability independently radiological findings. However, its usefulness is limited by the low percentage of CIS patients that presented at baseline an abnormality in the 3 PEs. The annex article is an attempt to reproduce the finding of a study (Berger et al, N Engl J Med 2003) in which was concluded that the presence of anti-myelin oligodendrocyte glycoprotein (anti-MOG) and anti-myelin basic protein (anti-MBP) antibodies in serum of patients with CIS was associated with an increased risk in the occurrence of a second relapse. We try to replicate these findings in a larger cohort, using the same technique for detecting antibodies with the same criteria for selection of patients. Finally 114 patients were included in the study, with a mean follow up of 47 months. In conclusion, patients with positive antibodies antimyelin did not show an increased risk of conversion to CDMS compared with those without their presence, so it is not shown that the presence of such antibodies is a marker of risk of conversion to CDMS.
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Vanden, Hoek Amanda Lynne. "Novel function of coagulation factor Xa : conversion into a clot-dissolving cofactor." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/36854.
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PLASMIN-MEDIATED CONVERSION OF FXa INTO A CLOT-DISSOLVING COFACTOR.
Factor Xa (FXa) is an essential blood clotting enzyme. A previously identified FXa derivative, Xa33/13, is generated by two distinct cleavages by the clot-dissolving (fibrinolytic) enzyme, plasmin. FXa is first converted to FXaβ by excision of a small C-terminal peptide and then proteolyzed at Lys330 in the autolysis loop to yield Xa33/13, which cannot participate in clotting. Instead, these cleavages confer novel fibrinolytic function to Xa33/13 as a tissue plasminogen activator (tPA) cofactor, thereby accelerating plasmin generation. To understand the importance of each cleavage and the role of individual residues in this functional conversion of FXa, five mutants were generated by mutation of basic residues to glutamine: Lys330 and four residues in the β-peptide region. Mutation at Lys330 prevented autolysis loop cleavage, and this mutant dissolved purified fibrin clots faster than plasma-derived FXa derivatives. Additionally, no basic residue within the β-peptide was uniquely targeted by plasmin and no single-point mutation in this region prevented subsequent autolysis loop cleavage.
FX-DEFICIENT PATIENT.
Factor X (FX) can be activated by two separate protein complexes, known as the initiating (extrinsic) and amplifying (intrinsic) tenases, which are assembled during coagulation. I describe a FX-deficient patient with a novel compound heterozygous mutation associated with differential clotting pathway function. Quantification of plasma FX antigen revealed 15 % of normal, which was consistent with extrinsic pathway activity. Intrinsic pathway activity was reduced to 5 % of normal, suggesting an activatable specific activity 3-fold lower than expected for this branch of the clotting pathway. DNA sequence analysis identified two heterozygous mutations: (1) a previously reported mutation that disrupts the splice site between exons I and II; (2) a novel mutation resulting in an Arg386Cys substitution in the protease domain. I propose that alternate disulfide bond formation and protein folding may reduce circulating FX antigen levels. Additionally, Arg386 may be involved in substrate recognition by the intrinsic tenase complex, providing a possible explanation for the differential effect on the two branches of the coagulation cascade. Recombinant FX mutant studies confirmed our findings in patient plasma and provided further support for these hypotheses.
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Cheng, Yuen Wah. "Ergosterol to fungal spore concentration conversion factors : determination and application to ambient aerosols /." View abstract or full-text, 2006. http://library.ust.hk/cgi/db/thesis.pl?EVNG%202006%20CHENG.
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Ait, Taouit Holly Danielle. "The Psychometrics of a Systematic Inventory of Motives for Converting to Islam." Xavier University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=xavier1460369945.
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Moody, Jena N. "Body mass index and polygenic risk predict conversion to Alzheimer’s disease." The Ohio State University, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=osu1618411580130641.
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Graham, James Fionnlagh. "An investigation into the subcellular localisation of co-factors that stimulate prion protein conversion." Thesis, University of Warwick, 2009. http://wrap.warwick.ac.uk/3649/.
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Aho, Yousef, and Johannes Persson. "Factors Affecting the Conversion Rate in the Flight Comparison Industry: A Logistic Regression Approach." Thesis, KTH, Matematisk statistik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-229741.
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Using logistic regression, we aim to construct a model to examine the factors that are most influential in affecting user behavior on the flight comparison site flygresor.se. The factors examined were number of adults, number of children, number of stops on the inbound trip, number of stops on the outbound trip, number of days between the search date and the departure date and number of search results displayed for the user. The data sample, collected during a one-week period, was taken from Flygresor and consisted of trips to or from Sweden, made within Europe, excluding Nordic countries, and made more than six days before departure. To find the variables which best explain the user behavior, variable selection methods were used along with hypothesis testing. Also, multicollinearity analysis and residual analysis were performed to evaluate the final model. The result showed that the factor number of children had no significant impact on the conversion rate, while the remaining factors had a high impact. The final model has a high predictive ability on the user's propensity to select a certain flight.Med hjälp av logistisk regression ämnar vi att ta fram en modell som beskriver vilka faktorer som påverkar användarbeteendet på prisjämförelsesajten flygresor.se. Faktorerna som analyserades var antalet vuxna, antalet barn, antalet mellanlandningar på utgående resa, antalet mellanlandningar på ingående resa, antalet dagar mellan sökdatum och avresedatum och antalet sökresultat som visas för användaren. Datat som användes var taget från Flygresor under en veckas tid, och bestod av resor till och från Sverige, gjorda inom Europa men inte till nordiska länder, med mer än sex dagar till avresedatum. För att hitta de variabler som förklarar användarbeteendet mest, användes olika urvalsmetoder och hypotesprövningar samt olika evalueringsmetoder som residualanalys. Resultatet visade att variabeln antalet barn inte hade någon signifikant påverkan på konverteringsgraden, medan resterande faktorer hade en hög påverkan. Den slutgiltiga modellen har en hög förmåga att förutse användarens sannolikhet att välja en specifik flygresa.
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Ortiz, Huari Henry Miguel, and León Marco Antonio Padilla. "Factores de riesgo para la conversión de la colecistectomía laparascópica." Universidad Nacional Mayor de San Marcos. Programa Cybertesis PERÚ, 2005. http://www.cybertesis.edu.pe/sisbib/2005/ortiz_hh/html/index-frames.html.
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La colecistectomía laparoscópica es aceptada como el procedimiento de elección para la colelitiasis en sus diversas formas de presentación. No obstante ciertos casos necesitarán conversión a colecistectomia abierta, por diversas razones y por seguridad del paciente. El presente estudio estuvo dirigido a identificar los factores de riesgo para la conversión de colecistectomía laparoscópica a colecistectomía abierta. Se realizaron 1,344 colecistectomías laparoscópicas, en el Hospital Nacional Arzobispo Loayza, en el periodo comprendido entre Enero a Diciembre 2002. Se hizo la revisión retrospectiva y se analizaron 37 variables que incluyen datos de la historia clínica, datos de laboratorio, informe ecográfico e informe de los detalles intraoperatorios. Se planteó un estudio de casos y controles, se realizó el análisis univariado para determinar cuales son los factores implicados en la conversión. Fueron convertidos a procedimiento abierto 115 (8.4%) casos. La edad promedio de conversión fue 48.6 años. El 52.2% de los convertidos fueron colecistitis aguda. El proceso inflamatorio severo ocasionó mas del 50% de conversiones. El resultado del análisis univariado indica que tienen significación estadística para la conversión: colecistitis aguda(x2 =25.8, p<0.0001), masa palpable(x2 =13.1, p<0.0001), fiebre(x2=9.6, p= 0.002), e ictericia(x2=8.8, p = 0.003). Así mismo leucocitosis (p<0.0001), fosfatasa alcalina (p<0.0001) y bilirrubina total (p<0.0001). La presencia de estos factores estuvieron asociados a la conversión de colecistectomía laparoscópica y los criterios para conversión fueron: proceso inflamatorio de difícil disección, necesidad de explorar la vía biliar sin contar con equipo adecuado y complicaciones transoperatorias.
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Padilla, León Marco Antonio, and Huari Henry Miguel Ortiz. "Factores de riesgo para la conversión de la colecistectomía laparascópica." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2005. https://hdl.handle.net/20.500.12672/1802.
Full textAbstract:
La colecistectomía laparoscópica es aceptada como el procedimiento de elección para la colelitiasis en sus diversas formas de presentación. No obstante ciertos casos necesitarán conversión a colecistectomia abierta, por diversas razones y por seguridad del paciente. El presente estudio estuvo dirigido a identificar los factores de riesgo para la conversión de colecistectomía laparoscópica a colecistectomía abierta.
Se realizaron 1,344 colecistectomías laparoscópicas, en el Hospital Nacional Arzobispo Loayza, en el periodo comprendido entre Enero a Diciembre 2002. Se hizo la revisión retrospectiva y se analizaron 37 variables que incluyen datos de la historia clínica, datos de laboratorio, informe ecográfico e informe de los detalles intraoperatorios. Se planteó un estudio de casos y controles, se realizó el análisis univariado para determinar cuales son los factores implicados en la conversión.
Fueron convertidos a procedimiento abierto 115 (8.4%) casos. La edad promedio de conversión fue 48.6 años. El 52.2% de los convertidos fueron colecistitis aguda.
El proceso inflamatorio severo ocasionó mas del 50% de conversiones. El resultado del análisis univariado indica que tienen significación estadística para la conversión: colecistitis aguda(x2 =25.8, p<0.0001), masa palpable(x2 =13.1, p<0.0001), fiebre(x2=9.6, p= 0.002), e ictericia(x2=8.8, p = 0.003). Así mismo leucocitosis (p<0.0001), fosfatasa alcalina (p<0.0001) y bilirrubina total (p<0.0001).
La presencia de estos factores estuvieron asociados a la conversión de colecistectomía laparoscópica y los criterios para conversión fueron: proceso inflamatorio de difícil disección, necesidad de explorar la vía biliar sin contar con equipo adecuado y complicaciones transoperatorias.Tesis de segunda especialidad
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Bumblauskas, Mangirdas. "Samogitia's Christianisation and the paganism factor (15-16th c.)." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2014~D_20140411_151000-25977.
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The work is devoted to elucidating the process of Christianisation of the last pagan region in Europe – Samogitia as a process of overcoming paganism or depaganisation in the 15th – 16th centuries. The main problem is a chronological difference in the conceptions that has existed in historiography for 500 years between what is considered to be the end of Samogitia’s Christianisation. This problem is solved, first of all, at a theoretical level taking over the conception of “conversion” from Western historiography applied to both political changes during the Christianisation period (the “official conversion”) and to the epoch of the society’s transformation from a pagan society into a Christian one (“conversion” in a broad sense).
Attempts are made in the thesis to show the main phases of Samogitia’s early Christianisation beginning with the stage of mission Christianisation whose main historical fact is Jeronimas Prahiškis’ mission in 1401–1404 that ended in the last victory of paganism. During the period of the “official conversion”, which encompasses baptising campaigns and the establishment of a diocese, the factor of paganism manifested itself in the pagan reaction – in the 1418 revolt, which failed to terminate the processes supervised by the international forum of that time – the Council of Constance. The end of the conversion in a broad sense is assessed according to the following indicators: the density of the network of parishes, the facts of the last baptisms of... [to full text]Darbas skirtas paskutinio Europoje pagoniško regiono – Žemaitijos christianizacijos kaip pagonybės įveikos arba depagonizacijos proceso XV–XVI a. išsiaiškinimui. Pagrindinė problema – istoriografijoje egzistuojantis 500 metų chronologinis sampratų skirtumas tarp to, kas laikoma Žemaitijos christianizacijos pabaiga. Ši problema sprendžiama pirmiausia teoriniame lygmenyje, perimant iš Vakarų istoriografijos „konversijos“ sąvoką, taikomą tiek christianizacijos politinių permainų laikotarpiui („oficialioji konversija“), tiek visuomenės virsmo iš pagoniškos į krikščionišką epochai („konversija“ plačiąja prasme). Disertacijoje siekiama parodyti pagrindinius Žemaitijos ankstyvosios christianizacijos tarpsnius, pradedant misijiniu christianizacijos etapu, kurios pagrindinis istorinis faktas yra Jeronimo Prahiškio misija 1401–1404 m., pasibaigusi paskutine pagonybės pergale. „Oficialiosios konversijos“ lūžyje, kuris apima krikštijimo akcijas ir vyskupijos įkūrimą, pagoniškasis veiksnys pasireiškė pagoniška reakcija – 1418 m. maištu, kuris vis dėlto nebenutraukė to meto tarptautinio forumo – Konstanco bažnytinio susirinkimo kuruojamo proceso. Konversijos plačiąja prasme pabaiga yra įvertinama pagal tokius rodiklius: parapijų tinklo tankis, paskutinių suaugusiųjų krikštijimų faktai, bažnyčių lankymo socialinės kontrolės sistemos faktai, dievų sąrašų bei pagoniškų praktikų liudijimai. Visi šie rodikliai leidžia teigti, kad XVII a. pradžią galima laikyti Žemaitijos konversijos pabaiga.
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Oguchi, Hiroshi, Masahiko Okumura, Kenji Matsumoto, Miyoko Fukuoka, Yuji Hanyu, and Fujio Araki. "Monte Carlo calculations of correction factors for plastic phantoms in clinical photon and electron beam dosimetry." AIP Publishing, 2009. http://hdl.handle.net/2237/20614.
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Ezzo, Issa. "Determination of the conversion factor for the estimation of effective dose in lungs, urography and cardiac procedures." Thesis, Stockholm University, Medical Radiation Physics (together with KI), 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-8520.
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Patient dose in diagnostic radiology is usually expressed in terms of organ dose and effective dose. The latter is used as a measure of the stochastic risk. Determinations of these doses are obtained by measurements (Thermoluminescent dosemeters) or by calculations (Monte Carlo simulation).
Conversion factors for the calculation of effective dose from dose-area product (DAP) values are commonly used to determine radiation dose in conventional x-ray imaging to realize radiation risks for different investigations, and for different ages. The exposure can easily be estimated by converting the DAP into an effective dose.
The aim of this study is to determine the conversion factor in procedures by computing the ratio between effective dose and DAP for fluoroscopic cardiac procedures in adults and for conventional lung and urography examinations in children.
Thermoluminescent dosemeters (TLD) were placed in an anthropomorphic phantom (Alderson Rando phantom) and child phantom (one year old) in order to measure the organ dose and compute the effective dose. A DAP meter was used to measure dose-area product.
MC calculations of radiation transport in mathematical anthropomorphic phantoms were used to obtain the effective dose for the same conditions with DAP as input data.
The deviation between the measured and calculated data was less than 10 %. The conversion factor for cardiac procedures varies between 0.19 mSvGy-1 cm-2 and 0.18 mSvGy-1 cm-2, for TLD respective MC. For paediatric simulation of a one year old phantom the average conversion factor for urography was 1.34 mSvGy-1 cm-2 and 1,48 mSvGy-1cm-2 for TLD respective MC. This conversion factor will decrease to 1.07 mSvGy-1 cm-2 using the TLD method, if the new ICRP (ICRP Publication 103) weighting factors were used to calculate the effective dose.
For lung investigations, the conversion factor for children was 1.75 mSvGy-1 cm-2 using TLD, while this value was 1.62 mSvGy-1 cm-2 using MC simulation. The conversion value increased to 2.02 mSvGy-1 cm-2 using ICRP’s new recommendation for tissue weighting factors and child phantom.
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Knight, Richard Thomas. "Absorbed dose conversion factors for therapeutic kilovoltage x-ray beams calculated by the Monte Carlo method." Thesis, Institute of Cancer Research (University Of London), 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389910.
Full textAbstract:
This thesis describes techniques for performing calculations of absorbed dose conversion factors for therapeutic kilovoltage and megavoltage x-ray beams, by application of the Monte Carlo method. These factors are low-energy x-ray backscatter factors, B, low- and medium-energy x-ray mass energy absorption coefficient ratios, water-to-air, We,IP)w.a,r ' and megavoltage x-ray stopping power ratios, water-to-air, s. The EGS4 and ITS Monte Carlo systems were used to model the relevant particle transport. Consistent theoretical expressions for absorbed dose in kilovoltage x-ray beams have been proposed. For low-energy x-rays, the expression for absorbed dose to water, D, requires values of defined as a water kerma ratio at the surface of a water phantom, and also of [(Jie,,/P)w.,r]p, evaluated over the primary spectrum (free-in-air). For medium-energy O x-rays, values of (Pen(Z,f)I'P)w,air are necessary, which are dependent on depth, z, and field-size,f. Bragg-Gray cavity theory entails values of SWthI(z) to convert readings from recommended ionisation chambers, calibrated in terms of air-kerma or exposure, into D. Bremsstrahlung spectra have been calculated by detailed Monte Carlo simulations of the NPL standard accelerator, a Philips SL series linac and a Siemens Stabilipan x-ray unit. Values of (i1 ,,/P)w air and B' have been calculated for therapeutic polyenergetic kilovoltage beams, over a comprehensive range of field sizes and beam qualities, following the Monte Carlo calculation of photon fluence in water and by a kerma-weighted averaging technique utilising primary fluence spectra and pre-calculated values of monoenergetic Values of Spencer-Attix s,, have similarly been calculated for the NPL standard and therapeutic linac beams following the Monte Carlo calculation of electron fluence in water and by a dose-weighted averaging technique utilising primary fluence spectra and pre-calculated monoenergetic dose distributions. Accurate TPR values, which account for linac spectrum quality shift off-axis, have been acquired by convolving water terma distributions with point-energy-deposition kernels. The beam quality dependence of N, the NFL absorbed dose-to-water calibration factor, has subsequently been investigated. Data appropriate for insertion into recommended expressions for D is presented and compared to data provided in the literature.
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Van, der Walt Franschua Johan. "Factors influencing the catalytic activity of Fe-ZSM-5 during the catalytic conversion of N₂O." Master's thesis, University of Cape Town, 2015. http://hdl.handle.net/11427/24323.
Full textAbstract:
Zeolites have found widespread applications as acid catalysts for decades. By introducing transition metal ions in the cation position, the zeolite is transformed into a redox catalyst. The nature of the trivalent heteroatom influences the properties of the zeolite. Contrary to Al-zeolites, Fe-containing zeolites show redox properties, since Fe can easily change its oxidation state (Fe²⁺, Fe³⁺, or Fe⁴⁺). Catalytic function of isolated redox sites within zeolite cavities (or channels) may result in a material with specific redox properties (Kiwi-Minsker et al., 2003). The properties of transition metal exchanged zeolites have been studied from the 1960's onwards and the conversion of N₂O over Fe-Y zeolites has been studied by Fu et al. (1981) in late 1970's. In this study, the preparation of iron ZSM-5 zeolite catalysts by mechanochemical means and thermally induced solid-state ion exchange was studied. After grinding the NH4-Zeolite and ferrous chloride, no x-ray reflections characteristic of ferrous chloride are detected. After heating the sample to 120 and 200 °C reflections characteristic of ferrous chloride are visible but disappear upon further heating to 300 °C. No porosity is observed after grinding and heating up to 200 °C as a result of pore mouth blocking. Moreover, upon heating up to 500 °C porosity starts to develop with pore volumes and pore sizes slightly lower than those of the parent zeolite. From the thermogravimetric analysis it is evident that the ion exchange takes place during calcination from 150 and 420 °C in agreement with the literature. In the second part of the study commercial Fe-ZSM-5 catalyst samples with different N₂O conversion activities (in the presence of H₂O and NO at 425 °C), ranging between 70 and 90 % (high, mid and low activity) are studied and characterised. The effect of temperature during calcination of the plant produced and laboratory calcined extrudate catalyst material was investigated. Panov et al. (1996) reported in the literature that the Fe²⁺ is oxidised to Fe³⁺ in the presence of N₂O forming what they called the α-oxygen, a form of active surface oxygen, with the evolution of molecular nitrogen. During the conversion, two surface α-oxygen atoms migrate, combine and desorbs as molecular oxygen from the surface. The α-oxygen forms between 200 and 350 °C and desorbs as molecular oxygen above 350 °C (Taboada et al., 2005). In this study, no correlation to N₂O conversion activity could be found for the α-oxygen content and correspondingly the concentrations of the respective iron oxides and iron hydroxides in the Fe-ZSM-5 samples.
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Assunção, Gabriel de Oliveira. "Conversor CA-CC trifásico de estágio único com elevado fator de potência baseado no conversor SEPIC MCD com interruptores bidirecionais." Universidade Tecnológica Federal do Paraná, 2016. http://repositorio.utfpr.edu.br/jspui/handle/1/2409.
Full textAbstract:
Este trabalho apresenta uma nova topologia de conversor CA-CC trifásico de estágio único com elevado fator de potência baseado no conversor SEPIC MCD, contendo interruptores bidirecionais. Este se comporta como um seguidor da tensão mesmo em malha aberta (característica dos conversores SEPIC MCD), ou seja, emula uma resistência do ponto de vista da rede elétrica. Sendo assim, o esforço de controle é reduzido a apenas uma malha de controle, sendo esta para controlar a tensão de saída, como em um conversor CC-CC. Este conversor de estágio único tem elevada confiabilidade, uma vez que emprega quatro interruptores ativos, com o mesmo sinal de comando, e seis diodos de alta frequência para a conversão de corrente alternada para corrente contínua (CA-CC) com alto fator de potência e isolação em alta frequência. Como desvantagens, tem-se a restrição na escolha da relação de transformação, a qual implica em elevados valores de corrente no secundário para baixas tensões de saída. São apresentadas as etapas de operação, as formas de onda ideais, as equações que regem o funcionamento do conversor, os resultados de simulação numérica contrastados com os valores teóricos e resultados experimentais. As especificações aplicadas ao conversor são 127 V na tensão de entrada, 200 V na tensão de saída, 50 kHz da frequência de comutação e 1500 W de potência para a carga. O protótipo gerado a partir dessas especificações apresenta 0,9981 de fator de potência, 4,234% de taxa de distorção harmônica e um rendimento de 85,522% para condições nominais. Devido as suas características, considera-se uma boa opção para sistemas trifásicos de baixa potência, onde não se justifica um elevado custo.This work presents a new three-phase high power factor single-stage AC-DC converter based on the DCM SEPIC topology, using bidirectional switches. This converter operates as a voltage follower even in open loop (SEPIC DCM converter characteristic), in other words, it emulates a resistance from the electric grid point of view. Therefore, the control effort is reduced to a single control loop to control the DC output voltage, like an output voltage control of a DC-DC converter. This single-stage converter has high reliability, since it employs four active switches with the same command signal and six high frequency diodes for AC-DC conversion with high power factor and high frequency isolation. A system disadvantage is related to the constraint in the choice of transformer turns, which leads to high current values in the secondary-side for lower output voltage specifications. Hereon are presented the operation modes, the ideal waveforms, the main equations of the converter, the numerical simulation results contrasting with the theoretical values and experimental results. Design specifications are 127 V input voltage, 200 V output voltage, 50 kHz switching frequency and 1500 W output power. The prototype is obtained by following the specifications and it shows 0.9981 of power factor, 4.234% of total harmonic distortion and 85.522% of efficiency for rated condition. This converter is considered a choice for low power three-phase systems with low cost realization.
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Sanchez, del Valle Rodrigo. "In vitro direct conversion of somatic cells from the adult human brain into functional neurons by defined factors." Diss., lmu, 2013. http://nbn-resolving.de/urn:nbn:de:bvb:19-153779.
Full text
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Knight, R. T. "Absorbed dose conversion factors for therapeutic kilovoltage and megavoltage x-ray beams calculated by the Monte Carlo method." Thesis, Institute of Cancer Research (University Of London), 1996. http://publications.icr.ac.uk/9719/.
Full text
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Reinholt, Brad M. "Conversion of equine umbilical cord matrix mesenchymal stem cells to the trophectoderm lineage using the Yamanaka reprogramming factors." Diss., Virginia Tech, 2015. http://hdl.handle.net/10919/74270.
Full textAbstract:
Induced pluripotent stem (iPS) cells that possess embryonic stem (ES) cell-like properties are generated through the use of the Yamanaka transcription factors, OCT4, SOX2, KLF4, and MYC (OSKM). Advanced transgene delivery methods utilizing non-integrating viruses for transduction of target cells has provided new opportunities for regenerative medicine in humans and other species. We sought to use this technology to generate equine iPS cells to address challenges in equine regenerative medicine. Umbilical cord matrix mesenchymal stromal cells (MSC) were transduced with the non-integrating Sendai virus encoding for the OSKM transcription factors. The cells initially were cultured on mouse embryonic feeder cells supplemented with LIF (10 ng/mL) and FGF2 (4 ng/mL). Transduction generated 21 initial colonies. Of these, four survived beyond 20 passages. The transduced equine cells morphologically resembled ES cells and expressed cell surface antigens indicative of ES cells. Molecular evaluation revealed the cells maintained expression of endogenous OSKM while the exogenous OSK transgenes were extinguished, but MYC was maintained. The transduced equine cells did not express the ES marker NANOG, but did express the trophectoderm markers CDX2 and TFAP2A. Both OCT4 and CDX2 were colocalized to the nucleus. The transduced equine cells were termed equine induced trophoblast (iTr) cells. Culture of the iTr cell in suspension resulted in formation of blastocyst-like spheres rather than solid cell aggregates indicative of ES and iPS cells. The iTr cells were transitioned to a feeder free monolayer culture. Transformation of the iTr cells to the spherical arrangement stimulated expression of genes that mark differentiation of trophoblast cells and up-regulated 250 transcripts over the monolayer arrangement. The iTr monolayer arrangement up-regulated 50 transcripts compared to the spherical arrangement. The iTr spheres respond to BMP4, EGF, and FGF2 by phosphorylating signal transduction proteins. Addition of BMP4, EGF, or FGF2 in combined pairs was able to alter TFAP2A, NEU1, and SLC35A1 expression. The generation of iTr cells by transduction of the Yamanaka reprogramming factors is not unique to equine cells. However, this report marks the generation of the first equine trophoblast cell line capable of recapitulating early equine trophoblast development. The new iTr line could prove valuable in gaining greater understanding of equine trophectoderm development.Ph. D.
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Fleck, Brett E. "Factors Affecting Agricultural Water Use and Sourcing in Irrigation Districts of Central Arizona." Thesis, The University of Arizona, 2013. http://hdl.handle.net/10150/301659.
Full textAbstract:
The purpose of this research is to quantify how macro-scale factors such as weather, crop prices, and land conversion affect agricultural water use at the irrigation district level in central Arizona and to understand what constraints and considerations district managers face when making water-sourcing decisions. A conceptual model is developed and econometrically estimated finding that much of the annual variation in total water use for agriculture can be explained by differences in precipitation, cotton prices, and alfalfa prices. Further, results from empirical analysis support the notion that total water use for agriculture has been greatly affected by land conversion from agriculture to other uses. Irrigation district manager interviews indicate that the water sourcing process is very similar across districts in central Arizona and has varied little since 1995, due to common constraints. This research lays an important foundation for future models designed to forecast agricultural water use in central Arizona.
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Kjaergaard, Fabian. "Terror, religion och radikalisering - exempel på bakomliggande riskfaktorer i förbrytarnas psyke och tidigare liv. : - En kvalitativ studie med utgångspunkt i Lewis R. Rambos omvändelseteori." Thesis, Uppsala universitet, Religionspsykologi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-385231.
Full textAbstract:
The purpose and aim of this research was to analyze if Lewis R. Rambos conversion the- ory can be applied to describe religious radicalization towards violent Islamic terrorism or not. The research has analyzed and investigated if there are any differences or similarities, regarding risk factors and existential dimensions before the attacks of three terrorists; Rakhmat Akilov, Mohamed Bouhlel and Salman Abedi. The report further considers what role Melder ́s eight existential dimensions play in violent Islamic radicalization. The analyzis is based on a deductive method where, as said above, the conversion theory, existential dimensions and risk factors are used to answer the research questions. This study analyses and encodes the material by hand with paper and pen, even though the program “OpenCode” is more commonly used in a thesis of this proportion, due to it provided a more flexibility. The conclusion of this study is that Rambo ́s theory can elucidate violent reli- gious Islamic radicalization but as the theory tends to be too broad and vague it should be used in combination with other theories to be able to fully explain the conversion. Other- wise the theory tends to be too broad and vague. Results of analyzing the risk factors and existential dimensions, shows that there are more similarities between the three terrorists than differences and that the existential dimensions do play an important role in the religious radicalization even though this theo- ry also can be to broad and vague because of a tendency by the dimensions to overlap.
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Scott, Elizabeth Ruth. "Monologue to dialogue : linguistic factors affecting the interactive conversation of young children with autism." Thesis, Queen's University Belfast, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.675429.
Full textAbstract:
Social communication is a primary difficulty in autism; however, whilst researchers characterise the communication of children with autism as delayed, deviant and atypical, there is a lack of underpinning evidence for these terms presented in the literature. The current researcher advances understanding of the communicative strategies of people with autism by developing a linguistic framework and highlighting pragmatic and prosodic speech strategies that are linguistically relevant for children with autism. Commonly, research highlights what children with autism are unable to do, for example understand metaphors (see, for example, Rundblad & Annaz, 2010). The researcher's original contribution to knowledge is the identification of both typical and atypical functional linguistic strategies which are adopted and exploited in their communication. The present study offers, therefore; something of a corrective to those studies which focus on the absence rather than presence of targeted language behaviours. The identification of these relevant strategies can provide typical speakers with an insight into how children with autism communicate, and have potential suggestions for clinical intervention. The study's speech data was collected at an autism-specific nursery run by the international charity, 8arnardo's, with the participation of 14 children diagnosed with autism (2;10-4;5 years). Quantitative and qualitative linguistic analyses are performed on segmental and suprasegmental features of the speech data collected. The analytic framework adopted reveals previously undocumented linguistic strategies used by the children with autism, such as prosody-only echolalia, sensory-motivated echolalia, and revelatory aspects to the questions asked and Politeness strategies employed by the children. The researcher suggests that people with autism are communicating, just perhaps not in a way which neurotypicals expect or understand. The overarching principle is that we should aim to find strategies and processes that underlie patterns in their communication; or, in other words, work towards uncovering the dialogue agendas of people with autism.
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Chávez, Segura César José. "Factores clínicos-epidemiológicos para la conversión de la colecistectomía laparoscópica a colecistectomía abierta del Hospital Nacional Arzobispo Loayza. Lima-Perú 2013." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2015. https://hdl.handle.net/20.500.12672/3994.
Full textAbstract:
Objetivo: Determinar las características clínicas-epidemiológicas para la conversión de la colecistectomía laparoscópica electiva a colecistectomía abierta del Hospital Nacional Arzobispo Loayza en el año 2013. Material y Métodos: Estudio descriptivo, retrospectivo, se recolectaron los casos de conversión de colecistectomía laparoscópica electiva a cirugía abierta y la información se obtuvo de los reportes operatorios e historias clínicas. La población fue de 80 casos de 18 a 92 años. Análisis de las variables epidemiológicas, clínicas, bioquímicas y de imágenes diagnosticas, identificación de la tasa de conversión. Resultados: 74 casos fueron incluidos en el estudio. El principal motivo de conversión fue la no identificación del Triangulo de Calot (54.05%). La conversión de colecistectomía laparoscópica a cirugía abierta predomino en el sexo femenino (59.46%). La edad promedio de los casos fue de 52.28 años, y el grupo de edad más frecuente fue el comprendido entre 51 a 70 años. En un 58.11% de los casos tenían antecedente de cirugía abdominal previa. Lo valores de bilirrubina total (>1.2mg/dl) fueron el 32.43% de los casos. El 66.22% de los casos presento un grosor de la pared vesicular mayor a 4mm. En la mayoría de los casos presentaron cálculos en la vesícula (97.3%). El diagnostico preoperatorio y postoperatorio más frecuente fue la colecistitis crónica (51.35%) y el plastrón vesicular (21.62%) respectivamente, El 17.57% de los casos presento alguna complicación postoperatoria. La estancia hospitalaria preoperatoria y postoperatoria fueron 4.81 y 6.94 respectivamente. Conclusiones: La principal característica clínica-epidemiológica para la conversión de la colecistectomía laparoscópica electiva a colecistectomía abierta fue la no identificación del Triangulo de Calot.Tesis
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Ewerling, Marcos Vinícius Mosconi. "Conversor CA-CC bridgeless monofásico de estágio único com PFC baseado no conversor SEPIC operando no modo de condução contínuo." Universidade Tecnológica Federal do Paraná, 2017. http://repositorio.utfpr.edu.br/jspui/handle/1/3022.
Full textAbstract:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Neste trabalho é apresentado a análise de um conversor CA-CC Bridgeless monofásico de estágio único com correção de Fator de Potência, baseado no conversor SEPIC isolado com os interruptores do lado CA. Para que o conversor exerça a técnica de correção de fator de potência, pelo fato de estar operando no modo de condução contínuo (MCC), é necessário controlar a corrente de entrada. Sendo assim, o sistema de controle, comparado caso o conversor operasse no modo de condução descontínuo (MCD), fica mais complexo, resultando em uma desvantagem para operação em MCC. Porém, quando se trata de rendimento, como os níveis de pico de corrente são menores operando em MCC, se espera obter um rendimento mais elevado. Além disso, com os interruptores do lado CA o conversor apresenta um número menor de semicondutores no caminho da corrente durante um período de comutação, comparado com a topologia convencional, sendo mais um ponto positivo se tratando do rendimento do conversor. São apresentadas as etapas de operação do conversor, as formas de onda ideais, tanto em alta frequência quanto em baixa frequência, a análise matemática contendo as principais equações que regem o funcionamento do conversor e a simulação numérica comprovando a análise desenvolvida. O conversor foi projetado para uma tensão de entrada de 127V com tensão de saída igual a 200V, operando com uma frequência de comutação igual a 50kHz e uma potência entregue a carga igual a 300W.
In this paper is presented the analysis of a single-phase bridgeless AC-DC converter with a single-stage of power factor correction, based on an isolated SEPIC converter with AC-side switches. Wherefore the converter carry out the power factor correction technic, by the act of operating in the continuous conduction mode (CCM), it’s essential to control the input current. Therefore, the control system, compared to the converter operating in the discontinuous conduction mode (DCM), become more complex, resulting on a disadvantage for the CCM. Nevertheless, when it’s come to efficiency, how the levels of peak current are smaller operating in CCM, it is expected to obtain a higher efficiency. Besides that, with the AC-side switches the converter presents a smaller number of semiconductors on the current path during a switching period, compared with the conventional topology, become one more positive advantage for the converter efficiency. Are presented the operation stages of the converter, waveforms, for high frequency as well as mains frequency, the numeric analysis possessing the leading equations for the converter operations and the numeric simulation proving the developed analysis. The converter was designed for a 127V input voltage, with a 200V output voltage, operating with a switching frequency of 50kHz, and a 300W rated output power.
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Bywall, Karin, and Timmy Rosendal. "Conversion to a Circular Industry : Success and limiting factors to convert Högdalen Industrial Area into an eco-industrial park." Thesis, KTH, Industriell ekologi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-189163.
Full textAbstract:
The concept of eco-industrial parks is a way to minimize environmental impact and resource use from an industrial area, and in this study the concept is applied to Högdalen industrial area in Stockholm. An interview study has been conducted with key actors in the area, which found for instance that there were a good cooperation will among the actors and some material and energy exchanges occurring. This was then compared to a literature study of the limiting and success factors of the development of an eco-industrial parks. A quarter of the identified factors were determined to have good prospects, a fifth was partly fulfilled, a fifth had bad prospects, a fifth was unknown and 15 % was unknown but relevant to uncover in this stage of development. For the future, it is suggested that: more interviews should be done with more actors in the area, Cleantech Högdalen should change focus to develop an eco-industrial park, more energy and material flows should be mapped and to gather information of unknown and relevant factors. The conclusion of this study is that there is potential to develop Högdalen Industrial Area into an eco-industrial park but there are some knowledge gaps about the quantitative minimization of resources and environmental impact.Konceptet eco-industrial parks bygger på att minimera klimatpåverkan och resursanvändning från ett industriområde, i den här studien är konceptet applicerat på Högdalens industriområde i Stockholm. En intervjustudie har utförts i området, där nyckelaktörer har intervjuats, studien visade bland annat att det är en generellt sätt god samarbetsvilja i området samt att några energi-och materialutbyten sker. Intervjustudien har jämförts med en literaturstudie av framgångsfaktorer och begränsande faktorer för utvecklingen av en eco-industrial park. En fjärdedel av de identifierade faktorerna har goda utsikter, en femtedel är delvis uppfyllda, en femtedel har dåliga utsikter, en femtedel är okända och 15 % är okända men relevanta i detta steg av utvecklingen. För framtiden föreslås intervjustudier med fler aktörer i området, Cleantech Högdalen bör ändra sitt fokus till att utveckla en eco-industrial park i området, fler energi- och materialutbyten bör kartläggas samt att information bör samlas om de faktorer som är okända och relevanta. Slutsatsen av studien är att det finns en potential att utveckla Högdalens industriområde till en eco-industrial park men att det är kunskapsluckor kring den kvantitativa potentialen att minimera resursanvändning och således också klimatpåverkan.
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Safi, Carl. "Microalgae biorefinery : proposition of a fractionation process." Phd thesis, Toulouse, INPT, 2013. http://oatao.univ-toulouse.fr/11469/1/safi.pdf.
Full textAbstract:
A primary algorefinery, concept that deals with the main components of microalgae (lipids, proteins, carbohydrates and pigments), has been studied. A sequence of unit operations has been implemented in order to obtain separated enriched fractions of these biomolecules by conserving their integrity in the downstream process. The study was mainly centred on Chlorella vulgaris, a species known for its rigid cell wall. Most of the lipophilic fraction (lipids and pigments) was recovered using supercritical carbon dioxide with ethanol as a co-solvent, without a preliminary unit operation of cell disruption. The hydrophilic fraction (proteins and polysaccharides) was recovered in the aqueous phase after bed milling as cell disruption method. Subsequently, the aqueous phase was fractionated into three fractions by means of a process of two-stage ultrafiltration. Thus, starches, pigments, proteins and sugars were successfully separated from each other. A life cycle assessment will be necessary to estimate the cost and the sustainability of the fractionation process.