Dissertations / Theses: 'Ota'

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Almerud, Eva-Kersti. "Ota Pavels sagovärld : Biografiska, narratologiska och språkliga perspektiv på Ota Pavels författarskap." Licentiate thesis, Stockholms universitet, Slaviska institutionen, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-111802.

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Abstract The present dissertation analyzes the role of the fairy tale in the literary works of the Czech author Ota Pavel. Ota Pavel (1930–1973) started as a sports reporter and later became a popular and esteemed writer of fiction, mainly short stories. His works have been translated to many languages, among them Swedish. The study consists of a biographical reading of Ota Pavel’s texts and a discussion of the function of the fairy tale in his stories. My analysis of his literary development and use of various prose elements is based on narratological theories of the fairy tale – Karel Čapek’s motifs and fairytale characters, Gérard Genette’s paratexts and Vladimir Propp’s functions and dramatis personae – and includes remarks on the function of diminutives, etc. Ota Pavel is also viewed in the context of the literary landscape of his time – the 1960s and 1970s – and the reception of his work is discussed. Pavel’s stories contain a number of characteristic features which together form his unique style: direct allusions and references to fairy tales--for example, fairies and witches – and the linguistic markers and distinctive use of the narrator’s voice. One of the most common characters in Ota Pavel’s work is the hero, who, often with the assistance of magical objects or supernatural helpers, defeats supernatural antagonists or solves impossible tasks. Developing and growing as he – the hero is usually male–strives toward his goal, Pavel’s protagonist struggles not with dragons and giants, but with himself and his own difficulties and misfortunes. Earlier research refers to Ota Pavel’s two “genres”: sports prose and retrospective, or “memory” prose. This study shows that the boundary between the two is fluid, and that all Pavel’s work might be called memory prose. The title of this thesis – Ota Pavels sagovärld (The Fairytale World of Ota Pavel) – indicates the perspective from which the subject is approached. On the one hand, it alludes to the influence of the fairy tale on Pavel’s work, while on the other it points to the fact that his own life was such that he sometimes needed to retreat into a fantasy world of his own. Keywords: Tjeckisk litteratur, saga, Ota Pavel, narratologi, Tjeckoslovakien

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Castellanos, Onorio Olaya Pirene. "Estudio de la estabilidad termica de la ocratoxina a durante el tostado del café (Coffea arabica)." Thesis, Montpellier 2, 2011. http://www.theses.fr/2011MON20033.

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L'ochratoxine A (OTA) est un métabolite secondaire produit par des espèces appartenant aux genres Aspergillus et Penicillium qui a été liée à certaines conditions avec des effets néphrotoxiques, immunotoxiques, tératogènes et cancérogènes. La présence d'OTA dans le café vert a été détectée depuis 1974 et sa transmission à la boisson a été mise en évidence en 1989. La torréfaction du café est un procédé thermique qui peut avoir un effet sur la teneur en OTA, avant 1988, on pensait que l'OTA était détruite pendant la torréfaction, mais après plusieurs chercher sont des résultats contradictoires publiés dans % de réduction (de 0 à 100%). Plusieurs auteurs émis les hypothèses suivantes pour expliquer cette réduction : Isomérisation de la toxine dans la position C3 formant un diastéréoisomère moins toxique (Studer-Rohr et al, 1995 et Bruinink et al, 1997), protection de la dégradation d’OTA par l'humidité du grain (Boudra et al 1995; Blanc et al, 1998 et Stegen et al, 2001.), existence de réactions avec le café toxine parent ou réarrangements de la molécule OTA à températures de torréfaction (Suarez-Quiroz et al, 2005). Une autre étude sur la dégradation thermique de OTA pure a montré la formation de deux composés moins toxiques, 14-(R)-ochratoxine A et de la 14-descarboxi-ochratoxine A (Cramer et al, 2008). Parce qu'il n'y a pas de données concluantes sur l'effet de la torréfaction sur l'OTA dans le grain et le besoin de bases scientifiques pour établir des règles pour l'exportation de café vert, l'objectif de ce travail était d'étudier l'impact des différents types de torréfaction sur la stabilité thermique de l'OTA dans le café et l'élucidation chimique des produits de transformation. Deux niveaux de contamination ont été obtenus à partir de café contaminés artificiellement par Aspergillus westerdijkiae (5,3 et 57,2 ppb d'OTA). Ces lots sont grillés à 230° en utilisant deux méthodes : La torréfaction à tambour (TR) et à lit fluidisé (LF). Les échantillons ont été prélevés toutes les 3 min pour TR et chaque min 0,9 pour LF pour quantifier la valeur résiduelle d¡¯OTA. Les résultats ont montré que le procédé de torréfaction par TR (plus lent) était plus efficace que la FL dans l'élimination de l'OTA (67% et 36%, respectivement, pour une torréfaction moyenne). Nous avons déterminé le taux de dégradation thermique de OTA pure et de l'OTA mélangée avec les composants du café (5 sucres, 3 acides aminés, la caféine et les acides chlorogéniques), montrant que les interactions se déroulent en fonction des conditions de pH et de pKa des composants testés, dans ce cas, en influant sur la réactivité et la vitesse de dégradation de l'OTA. Un produit de transformation (PT) a été observé sur les chromatogrammes obtenus à partir de l'interaction de l'OTA avec les composants du café. Des tests d'alcalinisation et de chauffage de OTA pure ont confirmé que le PT provient de la modification structurale de la molécule d'OTA et n’est pas un produit de l'interaction avec les composants naturels du café. L'effet du pH et de la température sur l'extraction de l'OTA dans le café contaminé a été testé dans ce travail, les résultats ont montré une plus grande extraction de la toxine à un pH de 8,5 et 6°. Au même pH à 20° il y avait une plus importante formation d'un produit de transformation. Le PT a été purifié pour mener à bien sa caractérisation chimique. La nature chimique du produit de transformation, les données spectroscopiques telles que celles obtenus sous UV-Vis (max: 237nm), l'affinité avec la phase mobile de l'OTA, l'analyse de l'alcalinisation (phénomène de régénération de l'OTA et PT), l'analyse d’isotopes stables (SIDA’s) et le spectre de masse (ion moléculaire M+1: 420 m/z), suggèrent que la structure de le PT d'OTA durant le processus de torréfaction correspond à un analogue de l'OTA qui conserve son groupe carboxyle acide et conformément à la fragmentation correspond à la Hydroxy-ochratoxine A (OH-OTA), avec des quantités mineures d’ OTA et de ses isomères
Ochratoxin A (OTA) is a secondary metabolite produced by species belonging to the genera Aspergillus and Penicillium and this toxin has been associated with certain illnesses within nephrotoxic effects, immunotoxic, teratogenic and carcinogenic. The presence of OTA in green coffee was detected in 1974 and its transmission into the beverage was made evident in 1989. Roasting coffee is a thermal process that have an effect on the OTA content. Before 1988 it was thought that the OTA was destroyed during roasting, but after several investigations, results published are contradictory results published in the % reduction (from 0 to 100%). Several authors have established hypothesis that try explain this reduction: Isomerization of the toxin in the C3 position forming a less toxic diastereomers (Studer-Rohr et al., 1995 and Bruinink et al., 1997), Protection of grain moisture degradation OTA (Boudra et al., 1995; Blanc et al., 1998 and Stegen et al., 2001), Existence of reactions with the parent toxin coffee or rearrangements of the OTA molecule roasting temperatures (200¡ã and 250¡ãC) (Su¨¢rez-Quiroz et al., 2005). Another study on thermal degradation of pure OTA showed the formation of two less toxic compounds 14 - (R)-ochratoxin A and the 14-descarboxi-Ochratoxin A (Cramer et al., 2008).Because there are no conclusive data regarding the effect of roasting on OTA in grain and the need for scientific bases for establishing regulations for export of green coffee, the objective of this work was to study the impact of different types of roasting on the thermal stability of OTA in coffee and chemical elucidation of the transformation products.Two levels of contamination were obtained by the contamination of coffee with a strain of A. westerdijkiae (5.3 and 57.2 ppb of OTA). These lots were roasted at 230 ¡ã C using two methods: Drum rotation (TR) and fluidized bed (LF). Samples were taken every 3 min from TR and every 0.9 min for LF to quantify the residual OTA. The results showed that in roasting process by TR (slower), it was more effective than with LF in the elimination of OTA (67% and 36%, respectively, for a medium roast). The thermal degradation rate of pure OTA and of OTA mixed with the components of coffee (5 sugars, 3 amino acids, caffeine and chlorogenic acids), were determined, showing that interactions took place dependent themselves on the conditions of pH and pKa values of the components tested, in this case by influencing by the reactivity and the rate of degradation of OTA. A transformation product (TP) was observed in the chromatograms obtained from the interaction of OTA with the components of coffee. A test of alkalinization and warming of pure OTA confirmed that the TP comes from the structural modification of the OTA molecule and is not a product of interaction with the natural components of coffee. The pH and temperature showed an effect in extraction of OTA in contaminated coffee, the results show better extraction of the toxin at pH 8.5 at 60 ¡ãC. At the same pH at 20 ¡ãC, it was shown a greater formation of the transformation product.The TP was purified to carry out its chemical characterization. The chemical nature of compound transformation and spectroscopic data such as UV-Vis (¦Ëmax: 237nm), the affinity with the mobile phase of the OTA, the analysis of alkalinization (OTA regeneration phenomenon and TP) analysis of stable isotopes (SIDA's) and the mass spectrum (molecular ion M +: 420 m / z), suggest that structurally the TP of OTA during the roasting process corresponds to an analogue of OTA which retains its acidic carboxyl group and in accordance to fragmentation corresponds to the Hydroxi- Ochratoxin A (OH-OTA), as well as minor amounts of OTA and its isomers

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Arnold, Matthew David. "Optimization Methods for a Reconfigurable OTA Chamber." BYU ScholarsArchive, 2018. https://scholarsarchive.byu.edu/etd/6733.

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Multiple-input multiple-output (MIMO) technology has enabled increased performance of wireless communication devices. The increased complexity associated with MIMO devices requires more realistic testing environments to ensure device performance. This testing can be accomplished by either very accurate but expensive anechoic chambers, less accurate but inexpensive mode-stirred chambers, or the newly introduced reconfigurable over-the-air chamber (ROTAC) that combines the benefits of both anechoic chambers and reverberation chambers. This work focuses on efficient optimization methods to quantify the performance of the ROTAC. First, an efficient optimization technique that combines convex optimization and a simple gradient descent algorithm is developed that can be applied to different ROTAC performance metrics. Plane wave synthesis is used to benchmark performance versus chamber complexity, where the complexity is defined in terms of chamber size and the number of ports in the chamber. Next, the optimization technique is used to study the spatial channel characteristics (power angular spectrum) of the chamber and the generation of arbitrary fading statistics inside the chamber. Lastly, simulation results are compared with practical hardware measurements to highlight the accuracy of the simulation model for the chamber. Overall, this work provides a comprehensive analysis for optimization of different ROTAC performance metrics.

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Volpe, Nathalie. "Naevus d'ota : a propos de deux cas ; revue de la litterature." Aix-Marseille 2, 1992. http://www.theses.fr/1992AIX20004.

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Ishikawa, Angélica Tieme. "Hibridoma OTA.1 : anticorpo anti-OTA no desenvolvimento da coluna de imunoafinidade e aplicação associada à qualidade e segurança de vinho." Universidade Estadual de Londrina. Centro de Ciências Agrárias. Programa de Pós-Graduação em Ciência de Alimentos, 2012. http://www.bibliotecadigital.uel.br/document/?code=vtls000183300.

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O consumo moderado de vinho é recomendado baseado em efeito benéfico à saúde especialmente contra radicais livres, destaque ao resveratrol. O monitoramento na cadeia produtiva de vinho deve ser executado por método rápido, sensível e específico, evitando contaminação por ocratoxina A (OTA). Considerando o emprego de bioferramentas, com destaque a coluna de imunoafinidade (CIA) na extração/concentração do analito de interesse e o ELISA (Enzyme-linked Immunosorbent Assay), como base para avanço tecnológico, a exemplo de biossensor, procedeu-se o cultivo de Hibridoma OTA.1 produtor de anticorpo monoclonal (AcM) anti-OTA. O cultivo de Hibridoma OTA.1 foi iniciado em meio RPMI 1640 suplementado com Soro Fetal Bovino (SFB) e L-glutamina, a 37 °C sob 5% CO2, e gradualmente substituído por meio Hibridoma-Serum Free Medium (H-SFM) nas proporções 15, 30, 50, 75, 80 e 100%. O enriquecimento com 7 mmol L-1 de L-glutamina e cuidado especial em etapa inicial de cultivo, propiciou adaptação e expansão celular. O AcM obtido foi precipitado com sulfato de amônio a 60 % de saturação, dialisado e empregado na confecção de 6 CIAs experimentais, imobilizando 5 mg de AcM 100 % H-SFM (CIA 1 e 2); 75:100 % H-SFM (1:1) (CIA 3, 4 e 5) e 75% H-SFM (CIA 6) em um mL de suporte Affi-gel 10, com modificações na metodologia padrão. A Taxa de imobilização variou de 77,43±6,39 a 97,55±0,24 %, sendo a CIA 6 desenvolvida com AcM 75 % de H-SFM dialisado em PBS 0,015 mol L-1, com acoplamento a 4 ºC/24 h, apresentou alta atividade anti-OTA por i-ELISA, sugerindo que proteínas inerentes ao próprio cultivo favoreceram a imobilização de AcM. Em paralelo, vinho argentino elaborado a partir de Vitis vinifera (n=26), bem como o vinho paranaense, de Vitis Labrusca- Bordô (n=34), foram avaliados perante contaminação de OTA por Cromatografia Líquida de Alta Eficiência (CLAE, Limite de detecção- LD =0,05 ng mL-1 e Limite de quantificaçao - LQ= 0,07 ng mL-1) e ELISA competitivo indireto (ic-ELISA, LD= 0,17 ng mL-1 e LQ= 0,32 ng mL-1); além de característica de qualidade avaliada por capacidade antioxidante (CAO), trans-resveratrol e parâmetros cromáticos (L*-luminosidade, C*-croma e hgraus -tonalidade cromática) foram analisados em 60 amostras. Apenas uma amostra (0,12 ±0,01 ng mL-1) apresentou contaminação de OTA por CLAE, e 11 por ic-ELISA, com nível de contaminação abaixo do limite estabelecido pela legislação brasileira e Comunidade Européia (2 ng mL-1). A detecção falso-positivo de OTA por ic-ELISA foi explicado pela relação de trans-resveratrol e OTA (Análise de Componentes Principais -ACP), mostrando interferência de matriz. O vinho elaborado com Bordô apresentou média de CAO 4,57 mmol L-1, enquanto o vinho elaborado com V. vinifera, 8,35 mmol L-1. O trans-resveratrol foi detectado em 57 amostras de 60, sendo o nível em vinho Argentino (1,35 mg L-1) mais baixo em relação ao vinho Bordô (3,33 mg L-1) (p<0,05). O vinho de Paraná apresentou maior luminosidade em relação ao argentino, i.e., cor mais clara, entretanto valores de croma e tonalidade cromática não diferiram estatisticamente (p>0,05). Os vinhos sul-americanos mostraram perfil interessante apresentando níveis alto de antioxidante e baixa contaminação por OTA. Por outro lado, nível elevado de trans-resveratrol atuou como interferente em ic-ELISA resultando em falso-positivo, o conhecimento dessa influência permitirá aperfeiçoar o emprego dessa bioferramenta sensível aplicado ao vinho.
Moderate consumption of wine is recommend based on beneficial effect on health, with emphasis on resveratrol against free radical. The monitoring of wine in the production chain should be performed by rapid, sensitive and specific method, avoiding contamination by ochratoxin A (OTA). Whereas the use of biotools, specially the immunoaffinity column (IAC) in the extraction/concentration of the analyte of interest and ELISA (Enzyme-linked Immunosorbent Assay), as a basis for technological advanced, such biosensor, we proceeded to the Hybridoma OTA.1 cultivation producing monoclonal antibody (mAb) anti-OTA. The Hybridoma OTA.1 cultivation was started in RPMI 1640 medium supplemented with Fetal Bovine Serum (FBS) and L-glutamine at 37 ºC with 5 % CO2, and gradually replaced by 15, 30, 50, 75, 80 and 100 % of Hybridoma-Serum Free Medium (H-SFM). The enrichment with 7 m mol L-1 L-glutmine in initial stage cultivation promoted adaptation and cell expansion. The mAbs obtained was precipitated with ammoniun sulfate at 60 % saturation, dialyzed and used in the confection of 6 experimental IACs with 5 mg of Mab 100 % (IAC 1 and 2); 75:100 % (IAC 3,4 and 5) and 75 % H-SFM (IAC 6) on one mL of Affil-gel 10, with modification in standard methodology. The rate of immobilization ranged from 77.43 ± 6.39 to 97.55± 0.24 %, the developed IAC 6 prepared with mAb produced in 75 % H-SFM, dialyzed in 0.015 mol L-1 PBS, with coupling step performed at 4 ºC/24 h, showed higher performance concerning anti-OTA activity evaluated by indirect ELISA, suggesting that proteins involved on own cultivation probably favored the mAb immobilization. In parallel, the Argentinean wine produced with Vitis vinifera (n=26), as well as Paraná wine produced with Vitis labrusca- Bordeaux (n=34), were evaluated concerning OTA contamination by High Performance Liquid Chromatography (HPLC, Limit of detection - LD =0.05 ng mL-1 and Limit of quantification - LQ= 0.07 ng mL-1) and indirect competitive ELISA (ic-ELISA, LD= 0.17 ng mL-1 and LQ= 0.32 ng mL-1); also quality characteristic targeted on antioxidant capacity (AC), trans-resveratrol and chromatic parameter (L*- brightness, C*- chroma e hº- hue) were determinate a total of 60 samples. Only one sample (0.12 ±0.01 ng mL-1) showed OTA contamination by HPLC and 11 samples by ic-ELISA, with levels below the limit established by Brazilian legislation and European Community (2 ng mL-1). The OTA detection by ic-ELISA was explained with the relationship of trans-resveratrol and OTA (Principal Components Analysis -PCA), showing the influence of matrix interference. The Bordeaux wine showed AC mean of 4.57 mmol L-1, while the same profile analysis in V. vinifera showed mean of 8.35 mmol L-1. The trans-resveratrol was detected in 57 out of 60 samples, the Argentina wine samples (1.35 mg L-1) showed lower trans-resveratrol level than Bordeaux wine (3.33 mg L-1) (p<0,05). The Paraná wine showed higher brightness in relation to Argentinean wine, i.e., lighter color, however chroma and hue values did not differ statistically (p>0,05). The South-American wines showed interesting profile concerning high level of antioxidants in detriment to lower OTA contamination. On other hand, high trans-resveratrol level acted as interference in ic-ELISA resulting in false positive, knowledge of this influence will improve the use of the sensitive biotool.

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Kode, Praveena. "Design techniques for high intermediate frequency bandpass (sigma/delta) modulator." Texas A&M University, 2008. http://hdl.handle.net/1969.1/86025.

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The focus of the present thesis is the circuit-level implementation of an excess loop delay compensation scheme which optimizes excess loop delay in Analog-to-Digital Converter(ADC) by using a programmable delay block and synchronizes the signal passing through Dynamic Element Matching block, used to mitigate mismatch effects of multi-bit Digital-to-Analog Converter(DAC). The proposed delay block has tuning range of T/10 to T/2 seconds, with a step size of T/30 seconds, where T is the time period (1.25 nanoseconds) of sampling signal (800 MHz) in high IF (200 MHz) Bandpass [sigma delta] ADC. The implementation details of the element rotation scheme used to calibrate the multi-bit DAC static error mismatch are also presented. Also presented is the design of high frequency highly linear Operational Transconductance Amplifier(OTA) targeted for continuous-time filters in a high resolution High Intermediate Frequency (200 MHz) Bandpass [sigma delta] ADC for Software Radio applications. Proposed OTA uses super source follower input stage to enhance its voltage-to-current conversion linearity. The design has been simulated using TSMC 0.18 μm CMOS process. The OTA has small signal transconductance of 0.9 mA/V, IM3 below -79 dB (for 0.3 Vpp input), Signal-to-Noise Ratio of 82 dB and power consumption of 6.8 mW, when tested in unity gain configuration.

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Rajaram, Dinakaran. "Secure Over the Air (OTA) Management Of Mobile Applications." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-116693.

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The Thesis report analyzes the possibility to store the application inside a secure environment in over the air Environment. The report clearly explains the details about the attributes which are placed in the over the air application management. Different forms of secure elements and how it can be placed inside the secure micro SD card have been discussed. The report gives the clear idea about secure micro SD card architecture. The report describes the OTA (Over the Air) components, Roles and also the process to manage the applications in OTA environment. The report also gives the clear about the protocols ISO 7816-4 which is used to communicate the handset with secure micro SD card. The communication concepts like establishing secure channel between the handset and secure micro SD card also has been discussed. Moreover, secure channel attributes are also discussed. They are Creation session key, MAC Operation and generation of derivation data. Secure micro SD card API‘s are also discussed which is used to communicate with the secure micro SD card .Some of the implementation work has been done by this research. They are >Constructed the Design of Trusted Service Manager (TSM) and Service provider. >Implemented the Functionality of TSM Server (Download Function) and tested the Functionality whether the end terminal (Android Phone) has been able to use the function properly. >Established the secure channel between the Android phone and secure micro SD card. >Loaded the sample application inside the secure micro SD card.

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Ramachandran, Arun. "Nonlinearity and noise modeling of operational transconductance amplifiers for continuous time analog filters." Texas A&M University, 2003. http://hdl.handle.net/1969.1/3925.

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A general framework for performance optimization of continuous-time OTA-C (Operational Transconductance Amplifier-Capacitor) filters is proposed. Efficient procedures for evaluating nonlinear distortion and noise valid for any filter of arbitrary order are developed based on the matrix description of a general OTA-C filter model . Since these procedures use OTA macromodels, they can be used to obtain the results significantly faster than transistor-level simulation. In the case of transient analysis, the speed-up may be as much as three orders of magnitude without almost no loss of accuracy. This makes it possible to carry out direct numerical optimization of OTA-C filters with respect to important characteristics such as noise performance, THD, IM3, DR or SNR. On the other hand, the general OTA-C filter model allows us to apply matrix transforms that manipulate (rescale) filter element values and/or change topology without changing its transfer function. The above features are a basis to build automated optimization procedures for OTA-C filters. In particular, a systematic optimization procedure using equivalence transformations is proposed. The research also proposes suitable software implementations of the optimization process. The first part of the research proposes a general performance optimization procedure and to verify the process two application type examples are mentioned. An application example of the proposed approach to optimal block sequencing and gain distribution of 8th order cascade Butterworth filter (for two variants of OTA topologies) is given. Secondly the modeling tool is used to select the best suitable topology for a 5th order Bessel Low Pass Filter. Theoretical results are verified by comparing to transistor-level simulation withCADENCE. For the purpose of verification, the filters have also been fabricated in standard 0.5mm CMOS process. The second part of the research proposes a new linearization technique to improve the linearity of an OTA using an Active Error Feedforward technique. Most present day applications require very high linear circuits combined with low noise and low power consumption. An OTA based biquad filter has also been fabricated in 0.35mm CMOS process. The measurement results for the filter and the stand alone OTA have been discussed. The research focuses on these issues.

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Mellgren, Eleine, and Amanda Stolt. "Effektivare webbplatser : hur tar hotellen tillbaka kontrollen?" Thesis, Örebro universitet, Restaurang- och hotellhögskolan, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-51874.

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Su, Hsiao Wei. "Design and performance of high-frequency CMOS-OTA-C filters." Thesis, University of Hertfordshire, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.251521.

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Tu, S.-H. "Analytical synthesis of OTA-C arbitrary and elliptic filter structure." Thesis, University of Southampton, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.689670.

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Lesonen, A.-J. (Antti-Jussi). "mmWave RX interference test considerations and challenges in OTA environment." Master's thesis, University of Oulu, 2019. http://jultika.oulu.fi/Record/nbnfioulu-201909242924.

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Abstract. Verifying equipment using the OTA (Over the Air) techniques is a recent addition in telecommunication testing. With the addition of new frequency bands, mmWave (millimetre wave) technology and massive MIMO (Multiple-Input-Multiple-Output), the 3GPP (3rd Generation Partnership Programme) has cemented OTA testing as the focus for verifying future equipment. However, these verifying methods are still in development, or stated as general ideas of how they are meant to be done. The main goal of this thesis is to study and design a system for receiver radio testing, according to 3GPP specifications. The test system must operate in mmWave frequency range and must be integrated to a pre-built antenna testing environment. The motivation is to verify the testing method proposed by 3GPP for mmWave receiver testing and analyse it thoroughly. This thesis aims to answer such research questions as: Is the testing method proposed by 3GPP valid for verifying mmWave frequency products? What are the major challenges, when designing test setup for high frequency devices? How can the method be improved and how it can be applied in the future? This thesis answers the first question by applying the proposed test methods in practical scenario and testing an actual eNB/gNB (eNodeB / Next generation eNodeB). Since the proposed test method has only general outline of what equipment to use, the actual test scenario will have additional pieces of testing equipment. For the second question, this thesis discusses the theory behind 5G and mmWave challenges, and how the use of these techniques is justified for practical usage. This theory is based on former research as well as current specifications applied by the 3GPP. The third research question is part of the final analysis, where the test results are analysed, and the major parts are discussed in depth. These discussions are then further expanded on with the purpose of suggesting possible areas of improvement as well as how to apply these findings into future use. The final outcome of the study is that the suggested test method is workings as it was presented by the 3GPP. However, there are some areas of improvement that should be discussed as a future work.Millimetriaaltojen RX interferenssi RF-testit OTA-ympäristössä. Tiivistelmä. Tuotteiden testaaminen ilmateitse on melko uusi lisäys tietoliikennetestauksen tekniikoihin, joita käytetään tuotteiden varmentamiseen. 3GPP on osoittanut OTA-testauksen keskeiseksi osaksi tulevien tuotteiden verifiointia. Osaksi tämä johtuu uusien taajuuskanavien käyttöönotosta, millimetriaaltoteknologiasta sekä massive MIMO tuotteiden yleistymisestä. Vaikka testaustapoja on jo ehdotettu, ne ovat vielä mahdollisesti vain yleisiä ideoita kuinka testejä tulisi suorittaa. Työn tarkoituksena on tutkia ja suunnitella vastaanottimen testaamiseen tehty testijärjestely. Testijärjestelyn tulee toimia millimetriaalloille tarkoitetulla taajuusalueella, ja työ tulee integroida valmiiksi suunniteltuun CATR-antennikammioon. Työn motivaationa on verifioida 3GPP:n ehdottama testausmetodi, millimetriaaltotaajuuksilla toimivien vastaanottimien toimivuus ja analysoida tämä tarkemmin. Tämä työ pyrkii vastaamaan tutkimuskysymyksiin kuten: Onko 3GPP:n ehdottama testimetodi pätevä verifioimaan millimetriaaltotaajuuksilla toimivia tuotteita? Mitä ovat suurimmat haasteet, kun suunnitellaan testijärjestelyä korkeataajuuksisille laitteille? Kuinka tätä metodia voidaan parantaa, ja kuinka sitä voidaan hyödyntää tulevaisuudessa? Työ vastaa ensimmäiseen tutkimuskysymykseen ottamalla käyttöön 3GPP:n ehdottamat testausmetodit käytännön testijärjestelyssä, ja testaamalla näillä metodeilla oikean tuotteen. Tällä tavoin ehdotettu testausmetodi pyritään verifioimaan. Tulee kuitenkin ottaa huomion, että ehdotetussa metodissa esitetään vain yleisellä tasolla mitä testaamiseen käytettävää laitteistoa käytetään. Tämän takia testeissä tulee olemaan joitain lisälaitteita, jotka ovat kuitenkin osa kokonaista testiympäristöä. Toiseen tutkimuskysymykseen perehdytään käymällä läpi teoriaa 5G:n ja millimetriaaltoteknologian haasteista, ja kuinka näitä tekniikoita tullaan hyödyntämään tulevaisuudessa. Teoria perustuu aiempaan tutkimukseen, sekä nykyisiin spesifikaatioihin jota 3GPP on kehittänyt. Kolmas tutkimuskysymys on osa lopullista analyysiä, jossa testien tulokset analysoidaan ja niiden pääkohdista keskustellaan tarkemmin. Tämän jälkeen keskusteluja täsmennetään liittyen mahdollisiin parannuksiin tietyllä aihealueilla, sekä mahdollisuuksista käyttää kyseisiä tuloksia tulevaisuudessa. Lopullinen päätelmä on, että ehdotettu testausmetodi toimii kuten se oli esitetty 3GPP:n dokumentoinnissa. On kuitenkin joitain osa-alueita, joita voitaisiin käsitellä tarkemmin tai jopa parantaa tulevaisuutta varten.

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13

Czajkowski, Ondřej. "Operační transkonduktanční zesilovač (OTA) pro využití v programovatelných analogových polích." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-219036.

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Operational amplifier will be designed and optimized with respect to set of required parameters. Real CMOS technology (available at Department of Microelectronics) will be used for designed OTA circuit and its simulations. Designed OTA will be used as universal operation amplifier configurable block in FPAA (field-programmable analog array) structures.

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14

Boscolo, Papo Giulia <1990&gt. "OTA e Hotel: il rapporto tra prenotazioni dirette e intermediate'." Master's Degree Thesis, Università Ca' Foscari Venezia, 2016. http://hdl.handle.net/10579/9310.

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La tesi ha lo scopo di analizzare, in primo luogo, il rapporto tra albergatori italiani e Online Travel Agencies, affrontando il tema della disintermediazione e della recente dichiarazione di nullità delle clausole che prevedono la parity rate. Si esamina il motivo del crescente utilizzo dei portali di prenotazione online da parte dei consumatori, studiandone il comportamento durante il processo decisionale. Infine vengono presentati i risultati di un'indagine, effettuata per comprendere le motivazioni che stanno alla base della scelta del canale di prenotazione online da parte dell'utente.

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15

Chan, Henry Hin Lee. "The use of laser in the treatment of naevus of Ota." Thesis, King's College London (University of London), 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.410036.

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16

Masood-ul-Hasan. "Design and test of high-frequency CMOS integrated OTA-C filters." Thesis, University of Hertfordshire, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.440161.

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17

Teng, Yueh-Ching. "Improved Synthesis Tool for Miller OTA Stage Using gm/ID Methodology." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1300912150.

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18

Rigobello, Fabiana Felipin. "Análise quantitativa de ocratina A (OTA) em plasma humano por ensaio imunoenzimático, e efeito citotóxico in vitro de OTA e FB1 em linhagem celular Jurkat e P3U1." Universidade Estadual de Londrina. Centro de Ciências Biológicas. Programa de Pós-Graduação em Patologia Experimental, 2015. http://www.bibliotecadigital.uel.br/document/?code=vtls000202853.

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Micotoxinas são metabólitos secundários de fungos pertencentes aos gêneros Aspergillus, Penicillium e Fusarium e são contaminantes naturais de alimentos no Brasil. Ocratoxina A (OTA) e Fumonisina B1 (FB1) são classificados como possível carcinógenos para humanos e animais (grupo 2B). Esta pesquisa objetivou introduzir metodologia de ELISA para analisar e quantificar a presença de OTA em plasma humano e avaliar o efeito de OTA e FB1 in vitro em linhagem celular P3U1 e Jurkat. Na primeira etapa do trabalho: (1) investigou-se a presença de OTA no plasma de pacientes por ELISA competitivo indireto usando anticorpos monoclonais (AcM) anti-OTA; (2) determinou-se a estimativa de ingesta diária de OTA por estes pacientes e; (3) avaliou-se a correlação da presença de OTA com marcadores plasmáticos de lesão hepática e renal. Os resultados obtidos demonstraram que OTA foi detectada em 55% das amostras (733,6 ± 296,04 pg/mL, máximo 1584,6 pg/mL), com uma estimativa de ingesta diária de 983,1-1445,3 pg/kg de peso corporal. Não houve correlação entre os níveis de OTA e parâmetros bioquímicos (AST, ALT, ureia e creatinina). Na segunda etapa, avaliou-se: (1) o efeito citotóxico de OTA e FB1, individualmente ou em associações, sobre linhagens celulares P3U1 e Jurkat, através do método de brometo de [3-(4,5dimetiltiazol-2-il)-2,5-difeniltetrazólio] (MTT) e dosagem de lactato desidrogenase (LDH) e; (2) a interação de AcM anti-OTA em células tratadas com OTA por imunocitoquímica. A viabilidade das células foi reduzida com exposição à 90 µg/mL de micotoxinas após 24 h, sendo que OTA reduziu a viabilidade de P3U1 e Jurkat de forma semelhante, e FB1 somente de célula Jurkat. O uso associado de OTA e FB1 não aumentou o efeito citotóxico sobre as células. Os métodos de MTT e LDH apresentaram forte correlação nas células Jurkat (r = 0,749) e P3U1 (r = 0,931). Imunocitoquímica confirmou a diminuição da viabilidade celular de Jurkat e P3U1 tratadas com OTA, bem como aumento de grânulos intracelulares marcados com substrato peroxidase e destruição da membrana plasmática com liberação do citosol, indicando a presença de OTA nestas células. Conclui-se que pessoas no Brasil estão contaminadas por OTA, porém o nível de contaminação está abaixo do limite tolerável divulgado por órgãos internacionais, e possivelmente esse é o motivo pelo qual não se observou correlação entre os níveis plasmáticos de OTA e parâmetros bioquímicos de lesão hepática e renal. Conclui-se com os resultados in vitro que a presença de OTA induz citotoxicidade, mas nas condições estudadas, a associação de OTA e FB1 não aumentou o efeito citotóxico.
Mycotoxins are secondary metabolites of some fungi from the genra Aspergillus, Penicillium and Fusarium and are natural contaminants of several foods in Brazil. Ochratoxin A (OTA) and Fumonisin B1 (FB1) are classified as possible carcinogens to humans and animals (group 2B). Current research aimed to introduce the use of ELISA to analyze and quantify the presence of OTA in human plasma and to evaluate the effect of OTA and FB1 in vitro on P3U1 and Jurkat cell lines. In the first phase of the research: (1) indirect competitive ELISA with monoclonal antibodies (mAb) anti-OTA was employed to detect the presence of OTA in human plasma; (2) the average daily intake of OTA was estimated and; (3) correlation was calculated between OTA and biomarkers for liver and kidney damage. Results showed that OTA was present in 55% of the samples (733.6 ± 296.04 pg/mL, maximum of 1584.6 pg/mL), with an estimated daily intake of 983.1-1445.3 pg/kg body weight. There was no correlation between the levels of OTA and biochemical parameters (AST, ALT, urea and creatinine). In the second phase of the research, it was evaluated: (1) the effect of OTA and FB1, individually or associated, on P3U1 and Jurkat cell lines by the 3-(4,5-dimethylthiazolyl-2)-2, 5-diphenyl- tetrazolium bromide (MTT) and lactate dehydrogenase dosage (LDH) assays and; (2) the interaction of mAb anti-OTA to OTA treated cells by immunocytochemistry. Cell viability was reduced after 24 h exposure to 90 µg/mL of the mycotoxins, with OTA reducing viability of P3U1 and Jurkat cells in similar ways, and FB1 only of Jurkat cells. The associated use of OTA and FB1 did not increase the cytotoxic effect on the cells. MTT and LDH had a strong correlation for Jurkat (r = 0,749) and P3U1 cells (r = 0,931). Immunocytochemistry confirmed the decrease of viability of P3U1 and Jurkat cells treated with OTA, with an increase of intracellular granules marked with peroxidase substrate and destruction of the plasma membrane with the release of cytosol, indicating the presence of OTA in these cells. It can be concluded that people in Brazil are contaminated with OTA, however, the level of contamination is below the limits established by international agencies, and possibly this is the reason why there was no correlation between OTA and the markers for liver and kidney damage. Also, the in vitro results demonstrate that OTA induces cytotoxicity, but under the studied conditions, the association of OTA and FB1 did not increase the toxic effect of the mycotoxins.

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Kliems, Alfrun. "Im Stummland : zum Exilwerk von Libuše Moníková, Jiří Gruša und Ota Filip /." Frankfurt am Main : P. Lang, 2003. http://catalogue.bnf.fr/ark:/12148/cb39208980v.

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20

Zhang, Ling. "System and circuit design techniques for WLAN-enabled multi-standard receiver." Columbus, Ohio : Ohio State University, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1131432639.

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21

Gomez, Quinones Jose. "Design and implementation of an application specific multi-channel stimulator for electrokinetically-driven microfluidic devices." Thesis, Grenoble, 2011. http://www.theses.fr/2011GRENT104/document.

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This dissertation presents the design and implementation of a 16-channel sinusoidal generator to stimulate microfluidic devices that use electrokinetic forces to manipulate particles. The generator has both, independent frequency and independent amplitude control for each channel. The stimulation system is based upon a CMOS application specific (ASIC) device developed using 0.35¦Ìm technology. Several generator techniques were compared based on frequency range, total harmonic distortion (THD), and on-chip area. The best alternative for the microfluidic applications is based in a triangle-to-sine converter and presents a frequency range of 8kHz to 21MHz, an output voltage range of 0V to 3.1VPP, and a maximum THD of 5.11%. The fabricated device, has a foot- print of 1560¦Ìm¡Á2030¦Ìm. The amplitude of the outputs is extended using an interface card, achieving voltages of 0V to 15VPP. The generator functionality was tested by performing an experimental set-up with particle trapping. The set-up consisted of a micromachined channel with embedded electrodes configured as two electrical ports located at different positions along the channel. By choosing specific amplitude and frequency values from the generator, different particles suspended in a fluid were simultaneously trapped at different ports. The multichannel stimulator presented here can be used in many microfluidic experiments and devices where particle trapping, separation and characterization is desired
This dissertation presents the design and implementation of a 16-channel sinusoidal generator to stimulate microfluidic devices that use electrokinetic forces to manipulate particles. The generator has both, independent frequency and independent amplitude control for each channel. The stimulation system is based upon a CMOS application specific (ASIC) device developed using 0.35¦Ìm technology. Several generator techniques were compared based on frequency range, total harmonic distortion (THD), and on-chip area. The best alternative for the microfluidic applications is based in a triangle-to-sine converter and presents a frequency range of 8kHz to 21MHz, an output voltage range of 0V to 3.1VPP, and a maximum THD of 5.11%. The fabricated device, has a foot- print of 1560¦Ìm¡Á2030¦Ìm. The amplitude of the outputs is extended using an interface card, achieving voltages of 0V to 15VPP. The generator functionality was tested by performing an experimental set-up with particle trapping. The set-up consisted of a micromachined channel with embedded electrodes configured as two electrical ports located at different positions along the channel. By choosing specific amplitude and frequency values from the generator, different particles suspended in a fluid were simultaneously trapped at different ports. The multichannel stimulator presented here can be used in many microfluidic experiments and devices where particle trapping, separation and characterization is desired

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22

Vora, Ashish. "A 90 dB, 85 MHz operational transconductance amplifier (OTA) using gain boosting technique /." Link to online version, 2005. https://ritdml.rit.edu/dspace/handle/1850/1319.

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23

Moloche, Díaz Marianela. "Ocratoxina A (OTA) en Ficus carica L. “higo” durante el proceso de cosecha." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2020. https://hdl.handle.net/20.500.12672/15395.

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Determina la ocratoxina A (OTA) en Ficus carica L. - higo‖ provenientes del distrito de Chilca, provincia de Cañete, departamento de Lima en diciembre del 2018. La ocratoxina A se determinó por el método de Cromatografía Líquida de Alta Eficacia (HPLC) mediante la extracción de la OTA en las muestras con soluciones de metanol y bicarbonato de sodio. Las concentraciones de OTA de las muestras de higo durante el tiempo de cosecha fueron entre 0,08046 y 0,0844 ug/kg de higo fresco; los niveles no fueron superiores al nivel tolerable establecido por los reglamentos de la Comisión Europea (10 μg/kg.) y el CODEX (10 μg/kg).
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24

Coelho, Gavin. "Ota-quadrotor: An Object-tracking Autonomous Quadrotor for Real-time Detection and Recognition." Thesis, University of North Texas, 2012. https://digital.library.unt.edu/ark:/67531/metadc115056/.

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The field of robotics and mechatronics is advancing at an ever-increasing rate and we are starting to see robots making the transition from the factories to the workplace and homes as cost is reduced and they become more useful. In recent years quadrotors have become a popular unmanned air vehicle (UAV) platform. These UAVs or micro air vehicles (MAV) are being used for many new and exciting applications such as aerial monitoring of wildlife, disaster sites, riots and protests. They are also being used in the film industry, as they are significantly cheaper means of getting aerial footage. While quadrotors are not extremely expensive a good system can cost in the range of $3000 - $8000 and thus too costly as a research platform for many. There are a number of cheaper open source platforms. The ArduCopter is under constant development, has the largest community and is inexpensive making it an ideal platform to work with. The goal of this thesis was to implement video processing on a ground control station allowing for the ArduCopter to track moving objects. This was achieved by using the OpenCV video-processing library to implement object tracking and the MAVLink communication protocol, available on the ArduCopter platform, for communication.

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Spiller, Luís Henrique. "Filtro OTA-C de baixa potência aplicado a um detector de atividade cardíaca." Florianópolis, SC, 2005. http://repositorio.ufsc.br/handle/123456789/102947.

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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia Elétrica.
Made available in DSpace on 2013-07-16T02:26:47Z (GMT). No. of bitstreams: 0
Este trabalho apresenta um sistema de detecção de atividade cardíaca para marca-passos baseado em estruturas de filtragem contínua OTA-C. A natureza da aplicação implica na minimização do consumo de potência do circuito para prolongar a vida útil das baterias que o alimentam. O filtro proposto usa transcondutores compostos por transistores MOS operando no regime de inversão fraca, onde a razão transcondutância por corrente de polarização é maximizada. O transcondutor é um par diferencial com degeneração de fonte para aumento da faixa de linearidade. Um circuito de realimentação de modo comum assegura a estabilização da tensão DC da saída diferencial do transcondutor em um valor pré-determinado. O filtro emprega estruturas completamente diferenciais e é dividido em blocos de segunda ordem para implementar a função de transferência desejada. Os controles da freqüência central do filtro e do ganho global são obtidos através de ajuste da corrente de polarização. Um comparador foi projetado para decidir se a saída do filtro corresponde ao evento de entrada monitorado. A performance do circuito final é verificada por simulação usando parâmetros fornecidos pelo programa MOSIS para a tecnologia AMIS 1,5µm. Os resultados demonstram a operacionalidade do filtro, mesmo quando são incluídos parâmetros tecnológicos associados ao descasamento dos transistores.

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CEDERCRANTZ, JAKOB. "Försäljning av flygbiljetter över internet : En studie om hur Scandinavian Airlines skulle kunna öka försäljningen av flygbiljetter via internet." Thesis, KTH, Industriell marknadsföring, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-149248.

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Under de senare åren har försäljningen av flygbiljetter och hotell på internet ökat. Det har tillkommit många nya företag som etablerats som internetresebyråer. Företagen har tagit marknadsandelar från flygbolagens egna försäljningskanaler vilket har gjort att flygbolagen tappat kontakten med kunderna. Detta medför att flygbolagen får svårare att veta hur deras kunder reser och de kan heller inte få kontakt med dem om det händer något oförutsett. Syftet med denna rapport är att identifiera vilka parametrar som styr kunden att välja var flygbiljetten ska bokas och på det viset kunna ta fram förslag på konkreta förbättringsåtgärder som skulle kunna göra SAS hemsida till en mer konkurrenskraftig försäljningskanal. För att uppfylla målet med denna studie har en marknadsundersökning gjorts bland passagerare på Arlanda flygplats. Undersökningen var i form av en muntligt framförd enkät där samma frågor ställdes till flera utrikesresande under olika dagar och tider i veckan. Resultatet av undersökningen visar att många kunder har låg lojalitet på internet. Valet av vilken aktör som kunderna väljer att boka sin flygbiljett beror oftast på priset. Av de respondenter som bokade sin flygbiljett hos en internetresebyrå gjorde 44 % det på en sida de aldrig bokat på förut. Respondenterna upplever dessutom ofta att det är billigare att boka sin flygbiljett på internetresebyråer och känner inget extra värde i att boka på SAS hemsida. Detta utgör ett visst hot mot SAS men samtidigt skapas möjligheter att utveckla och anpassa sidan efter kundens behov. En sambandsanalys visar att säkerheten att betala, snabbheten och enkelheten att boka en flygbiljett är de parametrar som ökar helhetsintrycket på sidan. SAS har ett lojalitetsprogram som kallas för EuroBonus där resenärer får poäng varje gång de reser med flygbolaget. Det senaste året har den Amerikanska internetresebyrån Expedia lanserat ett lojalitetsprogram. Kunderna som bokar sin SAS‐biljett på Expedia får både SAS Eurobonuspoäng och lojalitetspoäng som de kan utnyttja på Expedias hemsida. Dessa tjänster utgör ett hot mot SAS hemsida och försäljningen där kan minska om inte SAS utvecklar sitt Eurobonusprogram så att de kunder som handlar där får extra Eurobonuspoäng. SAS vill att de resenärer som åker med dem bokar sin flygbiljett på deras hemsida. De vill även att deras hemsida ska ge kunderna ett bra helhetsintryck av att vara en enkel plats att boka flygresor på. För att uppnå detta behöver de få mer information om kundernas bokningsbeteende. Slutsatserna av denna rapport är att SAS bör öka värdet för kunden i att boka sin flygbiljett på deras hemsida. De skulle till exempel kunna utveckla sitt lojalitetsprogram EuroBonus så att de kunder som bokar på hemsidan får extra bonuspoäng. De kan också satsa på att ha korta kampanjer med få destinationer under en begränsad tid. På grund utav tidsbegränsningen skulle det vara svårt för de personer som letar efter de billigaste biljetterna på en internetresebyrå att hitta dessa kampanjer. Det i sin tur skulle innebära att kunderna då måste besöka SAS hemsida. Är priserna tillräckligt attraktiva så kan SAS hemsida uppfattas som den billigaste kanalen i framtiden.
During the last few years, the airplane ticket sales have increased substantially. A lot of new companies have joined the market and established themselves as online travel agencies. The agencies have taken a significant market share from the airline company which has resulted in the airline companies loosing a lot of the consumer contact they used to have. The purpose of this report is to identify what parameters it is that lead the customers to choose where to buy airline tickets and by doing so be able to find ways to make SAS website more competitive. To fulfill the purpose of the report a face‐to‐face market survey has been done among passengers at Arlanda Airport. The survey has been performed all days of the week at several different times of the day. The result of the survey shows that many Internet customers are very disloyal and that the choice of channel mainly depends on the price. Out of the respondents who booked their ticket at an online travel agency 44% did it on a page they never booked at before. The respondents often feel that it is cheaper to book a flight on an online travel agency and do not feel any extra value in booking on the SAS website. This information can be seen as a threat to SAS but also as an opportunity to develop and customize the website to suit customer needs. A correlation analysis shows that the payment security, speed and simplicity of booking an airline ticket are the top parameters that increase the overall impression of the page. SAS has a loyalty program called EuroBonus where travelers get points every time they travel with the airline. This last year the American Internet travel agency Expedia has launched a loyalty program. Customers who book their SAS ticket at Expedia receive both SAS EuroBonus points and loyalty points to use at the Expedia website. These kinds of services can be seen as a threat and might lead to SAS falling behind in sales and even lose customers unless they join the trend and develop their loyalty programs on their own website. SAS would like the travelers flying with them to book the flight at their website. They also want the website to make a good impression being satisfying and easy to use when buying airplane tickets. To make this happen they need more information about the booking habits of their customers. The findings of this report is that SAS should add value for the customer who book their ticket on the SAS website. They could for example develop the Eurobonus loyalty program so that customers who book tickets on the website get extra bonus points. SAS can also try having short campaigns with only a few destinations during a limited period. Because of the time limitation it would be difficult for those who are searching for the cheapest tickets at an online travel agency to find these campaigns. This would mean that costumers will have to visit the SAS website. If the prices are attractive enough the SAS website might be perceived as the least expensive channel in the future.

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27

Mulyana, Ridwan S. "A Low Voltage, Low Power 4th Order Continuous-time Butterworth Filter for Electroencephalography Signal Recognition." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1281981810.

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Kilpijärvi, H. (Heli). "Hengitä ja ota askel eteenpäin:resilienssiin vaikuttavat tekijät trauman jälkeen ja kohtaamisesta traumataustaisen oppilaan kanssa." Master's thesis, University of Oulu, 2018. http://urn.fi/URN:NBN:fi:oulu-201809082766.

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Tämä on autoetnografinen tutkielma, joka kertoo yhden opettajan kokemana kasvusta yksilönä, ammatillisesta kasvusta, sekä traumataustaisen oppilaan kohtaamisesta tilanteessa, kun myös opettajalla itsellään on trauma taustallaan. Tutkielmassa tarkastellaan tekijöitä, jotka ovat mahdollistaneet trauman valjastamisen voimavaraksi. Vastaavasti tarkastellaan myös tekijöitä, jotka olisivat voineet aiheuttaa toisenlaisen lopputuloksen. Keskeisinä tarkastelun näkökulmina ovat resilienssi ja posttraumaattinen kasvu. Kriisi ja trauma eivät varoita tulostaan. Ne ovat yllättäviä, elämää perustavanlaatuisesti mullistavia tapahtumia, jotka voivat vaikuttaa syvästi sekä fyysiseen että henkiseen hyvinvointiin. On yksilöllistä ja tapauskohtaista, kuinka yksilö pystyy käsittelemään tapahtuneen ja millä tavoin se vaikuttaa hänen elämäänsä ja käyttäytymiseensä. Vaikka traumaa on tutkittu pitkään ja monin eri tavoin, sen vaikutuksista oppilaan käyttäytymiseen koulusituaatiossa ja opettajien valmiuteen kohdata traumataustainen oppilas on valitettavan vähän tutkimustietoa. Edelleen useat käyttäytymisen häiriöt luetaan ilkikurisuudeksi tai pahantahtoisuudeksi, vaikka taustalla voivat vaikuttaa vakavat traumaattiset kokemukset. Tämä aihe on erityisen ajankohtaista myös pakolaiskeskustelun osalta. Tämän tutkielman tarkoitus on avata näkökulmaa traumataustaisen oppilaan mahdollisesti poikkeavaan käytökseen sekä tämän kohtaamiseen. Tutkimusaineisto koostuu erityisopettajana työskentelyn aikana kirjoitetuista päiväkirjoista ennen vuotta 2018. Tutkijaa lukuun ottamatta kaikki mainitut henkilöt pysyvät tutkielmassa täysin anonyymeinä. Analyysimenetelmänä on käytetty sisällönanalyysiä, jonka avulla aineisto on koodattu esiin nousseiden teemojen mukaan ja aineistosta on paikallistettu toistuvat, hyvinvointiin ja resilienssiin vaikuttavat tekijät. Nämä on nimetty selviytymiskeinoiksi. Myös aikajana on merkityksellinen, sillä noin puolenvälin tienoilla aineistossa on havaittavissa henkinen muutos positiiviseen suuntaan. Lisäksi aineistosta on poimittu tekijät, jotka ovat uhkana hyvinvoinnille. Nämä on nimetty haavoittuvuuksiksi. Analyysissä on käytetty myös tilastollisia menetelmiä havainnollistaessa sisäisten ja ulkoisten vaikutteiden vaikutusta eri tekijöihin. Lopuksi tutkielmassa pohditaan opettajan ja traumataustaisen oppilaan suhdetta ja vuorovaikutusta, empatian merkitystä, myötätuntouupumusta ja auttajan etiikkaa. Mukana on myös esiin nousseita ajatuksia siitä, mikä voisi auttaa opettajaa traumataustaisen oppilaan kohtaamisessa.

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29

Fioravanti, Silvia <1996&gt. "Le OTA ed il marketing interculturale: presentare le strutture ricettive ai turisti dell’Asia Orientale." Master's Degree Thesis, Università Ca' Foscari Venezia, 2021. http://hdl.handle.net/10579/19840.

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Nel presente elaborato andremo ad analizzare in che modo si differenzi la presentazione delle strutture ricettive sulle principali Online Travel Agencies a seconda della cultura di appartenenza del turista a cui è rivolto l’annuncio. In particolare, ci concentreremo su due delle culture più rilevanti dell’Asia Orientale: la cultura cinese e quella giapponese. Iniziando con la profilazione del turista asiatico in modo da comprendere al meglio come la cultura ne influenzi le preferenze ed il comportamento d’acquisto, proseguiremo analizzando le principali OTA sia a livello italiano che orientale. In base alla letteratura sul marketing interculturale, saranno presi in analisi e confrontati tra loro una serie di annunci come riportati sulle OTA orientali rispetto a quelle italiane, al fine di rilevare le differenze nella presentazione della struttura a seconda del background culturale del turista leisure. Il fine ultimo di questa ricerca è dunque quello di portare alla luce come, tramite l’utilizzo di strategie di marketing interculturale rivolto ai turisti asiatici, venga formulata la presentazione dell’offerta alberghiera nelle principali destinazioni italiane.

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30

CAGNASSO, IRIS. "Innovative methods and metrological aspects applied to food safety: case studies of OTA and SO2." Doctoral thesis, Politecnico di Torino, 2022. http://hdl.handle.net/11583/2969833.

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Bessegato, Alessandra <1996&gt. "Le OTA e le politiche di discriminazione di prezzo: un’indagine sulla percezione del consumatore-turista." Master's Degree Thesis, Università Ca' Foscari Venezia, 2020. http://hdl.handle.net/10579/17703.

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Il progresso tecnologico che dalla seconda metà del ‘900 fino ai giorni nostri ha investito il nostro pianeta cambiando radicalmente pratiche e strategie di business, ha registrato i suoi maggiori effetti nel settore turistico. Si è passati infatti da una catena di valore che comprendeva un gran numero di fornitori ed intermediari di viaggio a quello che oggi viene definito Web 2.0 o Travel 2.0, dove i consumatori possono prenotare i servizi turistici da pc o smartphone direttamente dal comfort di casa propria. L’elaborato ha l’obiettivo di fornire una panoramica di come il settore turistico si sia evoluto, partendo dallo sviluppo dei primi modelli di business online, fino ad arrivare alle Online Travel Agency (OTA), che rappresentano il canale più utilizzato per la prenotazione dei servizi turistici. L’attenzione viene poi posta su quelle che sono le politiche di discriminazione di prezzo e di come queste siano applicate nel settore turistico e specialmente nelle OTA; viene inoltre posta una piccola parentesi su alcune tecniche di pricing psicologico. Successivamente il focus si sposta sul consumatore, dal processo che mette in atto per scegliere la vacanza al modo in cui questo percepisca il prezzo, lo interiorizzi e stabilisca se sia corretto oppure no. Infine, vengono illustrati i risultati di un’indagine condotta sul campo, che ha come obiettivo quello di confermare le teorie descritte nei tre capitoli precedenti e capire quale sia la percezione del consumatore sulle online travel agency e sulle politiche di prezzo.

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Robinson, Trevor P. "The Development of an Instrument to Measure the Self-Efficacy of Students Participating in VEX Robotics Competitions." DigitalCommons@USU, 2014. https://digitalcommons.usu.edu/etd/3077.

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The number of robotics competitions has steadily increased over the past 30 years. Schools are implementing robotics competitions to increase student content knowledge and interest in science, technology, engineering, and mathematics (STEM). Companies in STEM-related fields are financially supporting robotics competitions to help increase the number of students pursuing careers in STEM among other reasons. These financial supporters and school administrations are asking what the outcomes of students participating in competitive robotics are. Few studies have been conducted to investigate these outcomes. The studies that have been conducted usually compare students in robotics to students not in robotics. There have not been any studies that compare students to themselves before and after participating in robotics competitions. This may be due to the lack of available instruments to measure student outcomes. This study developed an instrument to measure the self-efficacy of students participating in VEX Robotics Competitions (VRC). The VRC is the world’s largest and fastest growing robotics competition available for middle and high school students. Self-efficacy was measured because of its importance to the education community. Students with higher self-efficacy tend to persevere through difficult tasks more frequently than students with low self-efficacy. A person’s self-efficacy has major influence over what interests, activities, classes, college majors, and careers he or she will pursue in life. The self-efficacy survey instrument created through this study was developed through an occupational and task analysis (OTA), and initial content and face validity was established through the OTA process. Exploratory and confirmatory factor analyses were also conducted to assist in instrument validation. The reliability was calculated using Cronbach’s alpha. Face validity was established through the OTA process. Construct validity was established through the factor analyses. The processes of the OTA and factor analyses have created an instrument that results indicate is reliable and valid to use in further research studies.

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Silva, Bárbara Ponzilacqua. "Avaliação de extratos de plantas quanto à atividade antimicrobiana e à detoxificação de micotoxinas." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/74/74131/tde-14022019-111351/.

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A exposição humana a microrganismos patogênicos e suas toxinas em alimentos constitui um grave problema de saúde pública. O uso indiscriminado de antimicrobianos convencionais promove o aumento da resistência dos microrganismos às principais moléculas existentes no mercado. Além disso, as limitações do uso de substâncias químicas em matérias primas alimentares têm estimulado pesquisas para o desenvolvimento de metodologias eco-amigáveis para evitar a multiplicação de fungos e/ou eliminar suas toxinas. O Staphylococcus aureus é uma das principais bactérias patogênicas que apresenta taxas elevadas de resistência aos antimicrobianos, e por este motivo tem sido objeto de estudo de pesquisas que tentam identificar novos compostos bioativos para o combate de infecções. O Aspergillus parasiticus é um dos principais fungos produtores de aflatoxinas, substâncias carcinogênicas que contaminam diversos tipos de cereais antes e após o processamento. Estudos recentes demonstraram que extratos de plantas possuem atividade antimicrobiana e antifúngica, além de potencial para degradação de micotoxinas. Neste contexto, o presente estudo teve por objetivos avaliar a atividade antimicrobiana in vitro de extratos brutos e liofilizados de folhas de maracujá, araçá, alecrim e orégano sobre células planctônicas de S. aureus e A. parasiticus, bem como verificar a capacidade dos referidos extratos em degradar in vitro a aflatoxina B1 (AFB1), ocratoxina A (OTA) e zearalenona (ZEA). Os efeitos antibacterianos e antifúngicos dos extratos foram avaliados através da determinação da concentração inibitória mínima (CIM) e concentração bactericida / fungicida mínima (CBM/CFM). Os ensaios de degradação da micotoxinas foram realizados em diferentes tempos de incubação (12-48 h) a 37º C, utilizando-se cromatografia líquida de alta eficiência (HPLC) para determinação das concentrações das micotoxinas. O maracujá não demonstrou atividade antimicrobiana tanto para S. aureus quanto para A. parasiticus. Dos quatro extratos estudados, o araçá demonstrou o maior efeito antibacteriano, cujos valores de CIM para extratos bruto e liofilizado foram 0.39 mg/mL e 0.45 mg/mL, respectivamente. Os menores valores de CIM para A. parasiticus foram obtidos com o orégano liofilizado (8.33 mg/mL) e o araçá bruto (3.215 mg/mL). Contudo, não foi possível identificar valores de CFM para o fungo analisado. Não houve efeito de degradação de OTA e ZEA por nenhum dos extratos avaliados. Todos os extratos reduziram a concentração de AFB1 após 48 h de incubação. A maior porcentagem (60.3%) de redução de AFB1 foi obtida com o extrato de alecrim após 48 h de incubação. A atividade antimicrobiana demonstrada pelos extratos das plantas avaliadas indica um potencial para sua aplicação no combate a bactérias patogênicas e fungos toxigênicos. Este é o primeiro estudo realizado com extratos dessas quatro espécies de plantas que evidenciou a capacidade de redução in vitro de AFB1.
Human exposure to pathogenic microorganisms and their toxins in food is a serious public health problem. The indiscriminate use of conventional antimicrobials increases the resistance of microorganisms to the main molecules available in the market. In addition, limitations on the use of chemical substances in food raw materials have stimulated researches for the development of eco-friendly methodologies to avoid the multiplication of fungi and/or eliminate their toxins. Staphylococcus aureus is one of the major pathogenic bacteria with high rates of antimicrobial resistance, and for this reason it has been the subject of research studies aiming to identify new bioactive compounds to combat infections. Aspergillus parasiticus is one of the main aflatoxin-producing fungi, which are carcinogenic substances that contaminate many types of cereals before and after processing. Recent studies have demonstrated that plant extracts have antimicrobial and antifungal activity, as well as potential for degradation of mycotoxins. In this context, the objective of the present study was to evaluate the in vitro antimicrobial effects of crude and lyophilized extracts of leaves from sweet passion fruit, araçá, rosemary and oregano on planktonic cells of S. aureus and A. parasiticus. The in vitro degradation of aflatoxin B1 (AFB1), ochratoxin A (OTA) and zearalenone (ZEN) by the crude extracts was also investigated. The antimicrobial and antifungal effects were evaluated by determining the minimum inhibitory concentration (MIC) and minimum bactericidal / fungicidal concentration (MBC / MFC). Mycotoxin detoxification assays were conducted at different incubation times (12-48h) at 37 °C. The concentrations of mycotoxins were determined by high performance liquid chromatography (HPLC). Sweet passion fruit had no antimicrobial activity on S. aureus or A. parasiticus. Out of the four extracts evaluated, araçá showed the highest antimicrobial effect with MIC of 0.39 mg/mL and 0.45 mg/mL for crude and lyophilized extracts, respectively. The lowest MIC values for A. parasiticus were obtained with lyophilized oregano (8.33 mg/mL) and crude araçá (3.215 mg/mL). However, no MFC values were obtained for the analyzed fungi. Although OTA e ZEN were not degraded by any extract evaluated, all extracts reduced the concentration of AFB1 after 48 h of incubation. The highest percentage of AFB1 reduction (60.3%) was obtained with rosemary extract after 48h of incubation. The antimicrobial activity demonstrated by extracts of the evaluated plants indicates a potential for application against pathogenic bacteria and toxigenic fungi. This is the first study carried out with extracts of these four plants species that demonstrated the in vitro ability for AFB1 reduction.

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Nayar, Ajith. "Interoperability in online travel distribution an investigation of the adoption of Open Travel Alliance (OTA) standards /." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 160 p, 2007. http://proquest.umi.com/pqdweb?did=1253510061&sid=2&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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35

Schröder, Rainer J. [Verfasser]. "Rechtsfrage und Tatfrage in der normativistischen Institutionentheorie Ota Weinbergers. : Kritik eines institutionalistischen Rechtspositivismus. / Rainer J. Schröder." Berlin : Duncker & Humblot, 2019. http://d-nb.info/1238292879/34.

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Coppetta, Calzavara Roberta <1996&gt. "Turismo tedesco in Veneto: un'indagine sui prezzi e la visibilità delle OTA in Germania ed Italia." Master's Degree Thesis, Università Ca' Foscari Venezia, 2020. http://hdl.handle.net/10579/18332.

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La tesi si occuperà di analizzare la domanda turistica tedesca in Veneto (in particolare, la sua segmentazione ed i trend turistici). Il tema principale verrà sviluppato con uno sguardo alla sostenibilità ed alle prospettive turistiche. Si attuerà un confronto tra un' OTA tedesca ed un' OTA italiana in relazione alle strategie di prezzo praticate ed ai possibili utilizzi della web reputation in materia di visibilità.

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37

El, Khoury André. "Champignons Mycotoxinogènes et Ochratoxine A (OTA) et Aflatoxine B1 (AFB1) dans les vignobles libanais : Occurrence et Origine." Phd thesis, Toulouse, INPT, 2007. http://oatao.univ-toulouse.fr/7651/1/el_khoury.pdf.

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L'étude de la dynamique des populations fongiques totales et mycotoxinogènes (OTA et AFB1) et du contenu de ces deux mycotoxines dans de raisins des vignobles libanais nous a permis de déterminer en premier lieu l'agent causal responsable de cette contamination. Il s'agit de l'espèce Aspergillus carbonarius responsable de la production de l'OTA et de l'espèce Aspergillus flavus responsable de la production de l'AFB1. Et, puisque la contamination en AFB1 semble être plus sérieuse, une étude portant sur l'influence de la température et de l'activité de l'eau (Aw) sur la croissance des champignons aflatoxinogènes et sur leur toxigénèse a été réalisée dans le but de mieux comprendre l'impact de ces deux facteurs importants. Une caractérisation moléculaire des champignons aflatoxinogènes grâce à la PCRRFLP ciblant l'espaceur inter génique (IGS) en utilisant l'enzyme de restriction Bgl II, nous a permis de différencier entre les espèces productrices de cette mycotoxine (Aspergillus flavus et Aspergillus parasiticus) sans toutefois passé par les techniques morphologiques longues et fastidieuses. Ceci rentre dans le cadre d'économiser le temps et le coût d'analyse et ouvre la porte sur la possibilité d'analyse par voie moléculaire qui s'avère une technique très précise, très rapide et beaucoup moins coûteuse.

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Visocchi, Pasqualino Michele. "Design of a fully tunable GaAs MESFET OTA - C integrator suitable for high-precision continuous-time filtering." Thesis, University of London, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.265246.

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Ota, Koji [Verfasser]. "Der freie Gebrauch des Eigenen : zur Konzeption von Bildung und ästhetischer Erziehung bei Friedrich Hölderlin / Koji Ota." Gießen : Universitätsbibliothek, 2015. http://d-nb.info/1070168394/34.

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Nogueira, Márcia Dimov. "Avaliação dos fatores de risco no processamento de café verde para o aparecimento de ocratoxina A (OTA)." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/9/9131/tde-03082017-180136/.

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Dentre os perigos relacionados com a produção de café verde, a ocratoxina A (OTA) é considerada significativa nesse produto. Com o objetivo de estudar a origem da OTA no processamento de café verde e avaliar os possíveis fatores de risco (região, etapas do processamento, fungos, insetos e ácaros) que poderiam contribuir na presença de OTA, foram amostradas três fazendas nos seguintes municípios: Bom Jardim (RJ), Espírito Santo do Pinhal (SP) e Cornélio Procópio (PR), onde havia a produção de café verde pela via seca e úmida. Foram coletadas 109 amostras de grãos de café, em diversas etapas do processamento, no período de maio a agosto de 2002. As amostras foram colhidas de acordo com fluxograma estabelecido e as etapas estudadas foram: cereja (campo), via seca, via úmida, armazém e café de varrição. Dessas amostras, 10 apresentaram OTA, que variou na sua quantificação de 3 a 101 ng.g-1. A maior prevalência de OTA foi a do café de varrição 57%, a via úmida apresentou uma prevalência de 10,3% e a via seca 7%. Na etapa cereja o fungo potencialmente toxigênico mais encontrado foi Penicillium spp, e quanto aos insetos, as larvas de Diptera e os Homoptera; na via úmida foram encontradas linhagens do Aspergillus seção Nigri e Circundatti e Penicillium spp, a infestação predominante foi a broca do café e os ácaros da família Acaridae; na etapa via seca registrou-se o isolamento de fungos do gênero Penicillium spp e Aspergillus seção Nigri , a broca do café foi a infestação predominante junto com os ácaros da família Acaridae, na etapa de armazém foram isolados Penicillium spp e Aspergillus seção Nigri, o inseto predominante foi a broca do café e os ácaros da família Acaridae; no café de varrição foram isolados Penicillium spp e Aspergillus seção Nigri e a broca do café estava presente junto com insetos da Ordem Diptera. Os resultados de cada etapa foram comparados por Análise de Variância em um nível de significância de 95%. Na análise de fatores de risco o café de varrição foi o mais significativo (p< 0,001).
The ochratoxin A (OTA) is considered to be among the most significant coffee contaminants with related hazards. With the purpose to study the origin of the OTA in the processing of green coffee and to evaluate the possible risk factors (region, step of processing, fungi, insects and mites) that could contribute in the OTA presence, had been selected three regions (states) of Brazil: Bom Jardim/RJ, Espírito Santo do Pinhal/SP and Cornélio Procópio/PR. A total of 109 samples of coffee beans were collected in conformity with flow chart established at different stages of ripening and processing: cherry (field), dry method, wet method, and warehouse and varrição coffee, from May to August of 2002. Of these samples 10 had presented OTA, which varied in its quantification from 3 to 101 ng.g-1. The biggest prevalence of OTA was the varrição coffee 57%, the wet method presented a prevalence of 10,3% and dry way 7%. In the stage cherry fungi potentially toxigenic was more found Penicillium spp, the insects had been the larvae of Diptera and the Homoptera; in the wet way it was found Aspergillus section Nigri and Circundatti and Penicillium spp, the predominant infestation was the coffee berry borer and the mite of the Acaridae family; in the stage wet methods spp was registered the isolation the Penicillium spp and Aspergillus section Nigri, the predominant infestation was the coffee berry borer together with the mites of the Acaridae family; in the stage of warehouse had been isolated Penicillium spp and Aspergillus section Nigri, and the predominant insect was the coffee berry borer and mites of the family Acaridae; in the varrição coffee had been isolated Penicillium spp and Aspergillus section Nigri the coffee berry borer was the most present insects together of Diptera. The results of each step had been with compared by Analysis of Variance. In the analysis of risk factors the varrição coffee\" was the factor most strongly related to the risk of the presence of OTA (p<0,001 ).

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Leal, Tânia Vanessa da Silva. "Innovative Ochratoxin A (OTA) extraction platforms using OTA-binding proteins." Master's thesis, 2018. http://hdl.handle.net/1822/59253.

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Dissertação de mestrado em Biotechnology
Wine is a widely consumed product that is often associated with contaminations of toxic metabolites called mycotoxins. The most important mycotoxin associated to wine is ochratoxin A (OTA), and its detection usually involves the clean-up of samples with immunoaffinity columns (IAC) and quantification by HPLC coupled with fluorescence detection (FL). However, the several drawbacks associated with the use of the IAC led to the search for alternative clean-up methods. Thus, in this work, new platforms for OTA clean-up from wine were developed, based on proteins whose affinity towards OTA makes them suitable candidates to mimic the binding properties of the antibodies used in the IAC method. In a first approach, a protein with high affinity towards OTA, was used to develop a new solid phase extraction (SPE) method for the extraction of the mycotoxin from wine and subsequent quantification by HPLC-FL. The capture of OTA by the columns constructed with agarose-immobilized OTA binding protein was optimized to allow the full recovery of OTA in wine, and the method was further validated by the evaluation of various parameters such as recovery rates, selectivity and limits of detection (LOD) and quantification (LOQ). The developed method was selective enough for a reliable determination of OTA in wine, presenting recovery rates superior to 98% and LOD and LOQ of 0.02 and 0.05 μg L-1, respectively. Furthermore, the performance of the developed method revealed no significant differences in relation to the IAC method in concentrations up to 2 μg L-1 of OTA. In comparison with other conventional SPE methods reported in the literature, the developed method has proved to be suitable to be employed in the determination of OTA in wine. In a second approach, the domain where lies the primary binding site of OTA in the OTA-binding protein used in the first approach was evaluated as OTA ligand for developing OTA extraction platforms based on this domain. For that, the domain was recombinantly produced, fused to a 6xHis tag, with and without the thioredoxin (TrxA) solubility partner, in two E. coli strains, BL21 (DE3) and Origami 2 (DE3). Soluble proteins, with and without TrxA, were produced by both strains, but the Origami strain provided higher yields of production (18.7 and 23.4 mg per litre of culture, respectively). In addition, differences observed in the affinity of the proteins for the nickel resin in the purification suggested that the structures acquired by the recombinant proteins produced in each strain were different. Furthermore, the fact that fusion proteins were less prone to degradation suggested that TrxA contributed for their stability. Studies of fluorescence spectroscopy revealed that only the recombinant proteins produced by the Origami strain were capable of interacting with OTA, thus indicating that these proteins were functional. The ability of the proteins produced from this strain, with and without TrxA, immobilized in nickel via the 6xHis tag, to capture the mycotoxin in buffer solutions was evaluated. SPE columns constructed with the nickel-immobilized recombinant proteins did not show the ability to effectively capture OTA. On the other hand, incubation assays performed in eppendorfs allowed decreasing OTA in solution up to 54 and 63%, respectively for immobilized proteins, with and without TrxA. These results open perspectives for the development of OTA extraction platforms based on the recombinant domain of this OTA-binding protein with matrixes less expensive than the agarose used in the first approach by means of specific purification tags.
O vinho é um produto largamente consumido que está frequentemente associado a contaminações com metabolitos tóxicos denominados de micotoxinas. A micotoxina mais importante associada ao vinho é a ocratoxina A (OTA), e a sua deteção envolve normalmente um passo de concentração das amostras com colunas de imunoafinidade (IAC) e deteção por HPLC acoplada com deteção por fluorescência (FL). Contudo, as diversas desvantagens associadas ao uso das IAC levaram à procura de métodos de concentração alternativos. Assim, neste trabalho, foram desenvolvidas novas plataformas de concentração de OTA do vinho, baseadas no uso de proteínas cuja afinidade para a OTA as torna candidatos adequados para mimetizar as propriedades de ligação dos anticorpos usados no método IAC. Numa primeira abordagem, uma proteína com alta afinidade para a OTA foi usada para desenvolver um novo método de extração em fase solida (SPE) para extrair esta micotoxina do vinho e subsequente quantificação por HPLC-FL. A captura de OTA por colunas construídas com a proteína em estudo imobilizada em agarose foi otimizada de forma a permitir uma recuperação total da micotoxina presente no vinho, e o método foi posteriormente validado através da avaliação de parâmetros como taxas de recuperação, seletividade e limites de deteção (LOD) e quantificação (LOQ). O método desenvolvido foi suficientemente seletivo para permitir uma quantificação confiável de OTA no vinho, apresentando taxas de recuperação superiores a 98% e um LOD e LOQ de 0.02 e 0.05 μg L-1, respetivamente. Em adição, o desempenho do método desenvolvido não apresentou diferenças significativas em relação ao método das IAC em concentrações até 2 μg L-1 de OTA. Em comparação com outros métodos convencionais de SPE reportados na literatura, o método desenvolvido revelou ser adequado para aplicação na determinação de OTA no vinho. Numa segunda abordagem, o domínio da proteína usada na primeira abordagem que contém o principal local de ligação da micotoxina, foi avaliado como ligando da OTA para o desenvolvimento de plataformas de extração de OTA baseadas nesse domínio. Para isso, este foi produzido de forma recombinante, em fusão com um 6xHis tag, com e sem tiorredoxina (TrxA) como parceiro de solubilidade, em duas estirpes de E. coli, BL21 (DE3) e Origami 2 (DE3). O domínio proteico solúvel, com e sem TrxA, foi produzido por ambas as estirpes, mas a estirpe Origami obteve maiores rendimentos de produção (18.7 e 23.4 mg por litro de cultura, respetivamente). Em adição, as diferenças observadas na afinidade das proteínas para a resina de níquel na purificação sugeriram que as estruturas adquiridas pelas proteínas produzidas em cada estirpe eram diferentes. Além disso, o facto de que que as proteínas de fusão se mostraram menos suscetíveis a degradação sugere que a TrxA contribuiu para a sua estabilidade. Estudos de espectroscopia de fluorescência revelaram que apenas as proteínas recombinantes produzidas pela estirpe Origami foram capazes de interagir com a OTA, indicando assim que estas se encontravam funcionais. A capacidade das proteínas produzidas por esta estirpe, com e sem TrxA, imobilizadas em níquel a partir do 6xHis tag, para capturarem a micotoxina em soluções tampão foi avaliada. Colunas SPE construídas com estas proteínas recombinantes imobilizadas em níquel não mostraram a capacidade de capturar efetivamente a OTA. Por outro lado, os ensaios realizados em “eppendorfs” permitiram reduções de OTA em solução até 54 e 63%, respetivamente para as proteínas imobilizadas com e sem TrxA. Estes resultados abrem perspetivas para o desenvolvimento de plataformas de extração de OTA baseadas neste domínio da proteína estudada com matrizes menos caras que a agarose usada na primeira abordagem por meio de tags de purificação específicos.

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Chuan-YuSun and 孫全佑. "A Fifth-Order Butterworth OTA-C Lowpass Filter with Multiple-Output Differential-Input OTA for ECG Acquisition." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/78554n.

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碩士
國立成功大學
電機工程學系
105
This study proposes a fifth-order Butterworth operational transconductance amplifier-C (OTA-C) low-pass filter (LPF) with multiple-output differential-input (MODI) OTA structure and metal–insulator–metal capacitors for electrocardiography applications. The current division technology is used as an alternative output pair to provide multiple outputs and achieve high linearity. This technique reduces the number of OTAs of the fifth-order LPF from 11 to 6 as compared with the conventional structure. The design issue of linearity and noise are also considered in the implementation of LPF. In order to achieve a filter with large-time constant and low noise, linearized MODI OTA structures with reduced transconductance and impedance scaler circuits for capacitors are used. OTA-based circuits is operated in the subthreshold region and supply voltage of 1V to conserve power consumption due to the battery life of the portable device and the critical area of the digital processor required in the circuit. The proposed filter is fabricated in a 0.18 µm complementary metal–oxide–semiconductor technology with a core area of 0.135 mm2. The experimental results show that the dynamic range (DR) is 58.44 dB, achieved a total harmonic distortion (THD) of -59 dB under a bandwidth of 250 Hz and input voltage of 100 mV at a 1 V supply voltage. The total power dissipation is 390 nW.

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Fu, Ren-Hong, and 傅仁弘. "Automatic Process Sensitivity Reduction for OTA Circuits." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/w9xpg7.

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碩士
國立中央大學
電機工程研究所
97
With the advance process technology, process variation has more and more impacts on the device behaviors, which reduces the design yield dramatically. In order to solve this problem, design-for-yield (DFY) techniques are hot research topics recently. In the DFY design flow, the influence of process variation will be considered at early design stage to reduce the process variation impacts on the circuits. In this thesis, an automatic DFY approach is proposed for OTA circuits to reduce their process variation sensitivity. According to the relationship between transistor sizes and process variation sensitivity, the proposed flow automatically adjusts the transistor sizes to reduce process variation sensitivity of OTA circuits. This flow has been implemented by C language. With little changing on circuit performances, this program will find an optimal solution considering the process sensitivity and area overhead using simulated annealing algorithm. As shown in the experimental results, the proposed approach does reduce the process variation sensitivity and improve the design yield.

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Tu, Shu-Hui, and 涂淑惠. "OTA-C Arbitrary-Phase-Shift Sinusoidal Oscillators." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/hfsmbt.

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博士
國立臺北科技大學
電腦與通訊研究所
100
In 2008, a fractional calculus approach (due to the phase of sα, απ/2, where 1＞α＞0) was applied to generate a second-/third-order arbitrary-phase-shift sinusoidal oscillator (APSO), whereas the approach is rather complicated. In addition, with a fractional order α of Z =1/Csα, where α = 0.5 or α < 1, the fractional capacitance imitated by a semi-infinite series of RC trees suffers from limited investigations because of the nonexistence of a real fractance device. How to generate an APSO using a simple methodology and practical elements (easy to be fabricated on an IC chip) is worthy of continued investigation. In the thesis, both the characteristic equation of an nth-order sinusoidal oscillator and the sub-transfer function of a quadrature as a core are simultaneously used to synthesize an nth-order OTA-C quadrature sinusoidal oscillator (QO). Furthermore, the QO is advanced to an nth-order APSO by phase transformation from a quadrature to an arbitrary phase shift via selectively superposing a required number of single-ended-input (SEI) operational transconductance amplifiers (OTAs) with +/− transconductances in parallel with assigned grounded capacitors on the QO. Such advancement acquires no extra circuitries in the feedback loops. The phase shift accuracy is essential for the output parameter of an nth-order arbitrary-phase-shift sinusoidal oscillator. Since some particular and small part in the APSO may individually and arbitrarily determine the phase shift between two relevant nodal voltages, the synthesis presented in this thesis contributes the advantage which is capable of applying compensation to the sub-circuitry relative to each phase shift. Six compensation schemes for reducing the phase shift deviation are proposed with carefully considering the non-ideal frequency dependent transconduc- tance of an OTA and its input and output parasitics. In 2009, a native amplitude limiting control for an oscillator was reported without extra sub-circuitries. However, how to reduce rather high variation of THD with respect to amplitude change of the scheme is a piece of valuable work. A transconductance of an OTA employed may be assigned and fixed by magnifying the length of MOS gate and the bias current properly. In addition, when the length of MOS gate is magnified, the output current with respect to input voltage difference is with a broader level between the maximum and minimum output currents. The broader the level between the maximum and minimum output currents is the higher the amplitude of output oscillation signals. Based on energy conservative theorem, the larger input bias current produces the higher output oscillation signal. A new native amplitude limiting scheme without using extra sub-circuitries is then presented which enjoys lower variation of THD with respect to amplitude change. Finally, H-Spice simulations and one discrete component experiment are used to validate theoretical predictions.

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Raible, Karl-Friedrich. "Die Integration des monetären Sektors in das Modell des Dritten Weges : ein Beitrag zur Weiterentwicklung der Lehren von Ota Sik /." 1991. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=002731251&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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Han, Cheng-ping, and 韓承平. "Low Voltage, Low Power CMOS OTA and COA." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/51455877294100699144.

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碩士
國立中山大學
電機工程學系研究所
92
Low voltage, low power amplifiers are proposed. One of the operational amplifiers is an Operational Transconductance Amplifier (OTA) with wide input and output swing and constant gm. The second and third amplifiers are high-performance Current Operational amplifiers (COAs). All amplifiers have power supply as low as one threshold voltage plus two overdrive voltage. In this thesis, the supply voltage is 1V. Simulation results show that the OTA has the maximum linear range over 0.7V. The transconductance can be 147μA/V, the power consumption is 0.133mW. There are two designs of the COA. Simulation results show COA(1) with a current gain of 143. The input impedance is 110Ω, the output impedance is 240KΩ and the power consumption is 0.15mW. In the simulation results of the COA(2), the current gain is 110. The DC power dissipation is 0.07mW. The input and output impedance are 95Ω and 500KΩ, respectively. All the proposed amplifiers are implemented on a TSMC 0.35μm 2p4m CMOS process technology and analyzed using HSPICE.

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HUANG, ERH-WEN, and 黃而汶. "OTA Full Anechoic Chamber Practical Advantages of Miniaturization." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/65155598680349523996.

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Hsu, Cheng-Chung, and 許正忠. "Structural Design and Testability Analysis of OTA Filter Circuits." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/27970279624259115141.

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博士
國立臺灣大學
電機工程學研究所
88
Abstract This thesis addresses the structural generation, analysis and synthesis of multiple loop feedback voltage-mode and current-mode operational transconductance amplifier and grounded capacitor (OTA-C, Gm-C) filters. A number of arbitrary order architectures including canonical realizations are developed. A general method for sensitivity analysis of the structures is also formulated. According to the sensitivity approach, we study the testability of OTA-C filters in the frequency domain by introducing the analog fault observability concept. The proposed methodology indicates the set of adequate test frequencies and test nodes to increase fault observability. A design for testability (DFT) approach to improve the controllability and observability of internal signals in the multi-stage OTA-C filters is also presented. The proposed DFT approach is effective in detecting single and multiple faults. Finally, a novel built-in self-test (BIST) structure based on OTA-Cs for the fault diagnosis of analog circuits is proposed. The proposed analog BIST structure can be used to increase the number of test points, sampling and controlling of all test points with voltage data, and making less time for test signal observable. The physical layouts, simulation results and experimental measurements are also presented to confirm the theoretical analysis.

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Huang, Keh-Chang, and 黃克昌. "OTA Realization and Testable Design of LC Ladder Filters." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/18891451801335336948.

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碩士
國立東華大學
電機工程學系
91
Abstract This thesis addressed a systematic design procedure of LC ladder filters by using operational transconductance amplifiers (OTAs) and capacitors, which can provide simple design flows for higher order filter design. From the view of achieving high reliability in integrated circuits (ICs) designs, a design for testability (DFT) approach which improves the controllability and observability is incorporated herein. This thesis also introduces the sensitivity analysis for the sake of presenting the DFT approach completely. The sensitivity analysis exhibits the set of adequate test frequencies and provides the useful information about analyzing the testability, improving the observability, and planning a suitable test strategy of circuit under test (CUT). The proposed DFT approach is effective in detecting circuit faults and succeeds to achieve the fault isolation. Furthermore, this thesis permits simpler design flows, lower area overhead and higher fault coverage. The physical layouts and simulated results are also presented to confirm the theoretical analysis.

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Tsai, Jia-Feng, and 蔡佳峰. "1-V Low-Power OTA-C Filter for ECG." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/14942031467282196079.

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碩士
國立中正大學
電機工程研究所
100
In this thesis, a low power OTA-C lowpass filter for ECG detection was implemented. In order to approach the maximally flat in passband, the Butterworth topology was chosen in the filter system. For ECG detected application, the cutoff frequency of lowpass filter was design at 250Hz. Two kinds of transconductance amplifier are improved from previous work[5], the first one is to change the drain voltage of input transistors and propose an Active Load OTA; the second one is to use the current of current division tech. as another output pair and keep the characteristic of current division tech simultaneously. And re-assign the current of input transistor, we can get two output pairs which have the same transconductance value. We can reduce the number of OTA of 5th lowpass filter system from 11 to 6. The chip of MODI OTA-C filter used TSMC 0.18μm Mixed Signal 1P6M CMOS process and its area was 0.136mm2. According to the measured results under 1V supply voltage, the total power consumption was 335nW, THD was about -32dB for 200mVpp input. And the bandwidth was below 250Hz can be adopted to eliminate the out-of-band interference of the ECG signal.

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