Tesis por compendio / [ES] En esta tesis se ha abordado el desarrollo de biosensores ópticos label-free, basados en tecnología de disco compacto, permitiendo así abaratar y simplificar su fabricación. El trabajo llevado a cabo ha consistido en estudiar diferentes propiedades físico-químicas desarrolladas por diversos materiales. Ello ha permitido obtener sistemas compactos y accesibles, capaces de sensar con buenas prestaciones analíticas en diferentes escenarios. En el capítulo 1 se presenta un estudio de inhibición enzimática sobre discos Blu-ray como plataforma de ensayo para el cribado de fármacos. Para ello, se inmoviliza orientadamente una glicoenzima, de la familia de las peroxidasas sobre la superficie del disco, cuya actividad se relaciona con los compuestos a cribar. Después de ensayar cada compuesto, se determina el grado de inhibición enzimática mediante la adición de un sustrato. La cantidad de producto obtenido, inversamente proporcional al potencial inhibitorio del compuesto en estudio, es cuantificado con un lector de discos que registra las variaciones en la intensidad del haz laser reflejado debidas al producto enzimático. Ello permite realizar más de 1700 ensayos simultáneos en un único disco Blu-ray lo que muestra su potencial en análisis masivo de alto rendimiento. Además, se plantea una estrategia basada en hipersuperficies para el análisis de la elevada cantidad de datos que se generan en las etapas del proceso de descubrimiento de fármacos. En el capítulo 2 se aborda el estudio de una metodología para reducir el ruido generado en la lectura de resultados obtenidos con biosensores ópticos, mejorando así su sensibilidad. Para ello, se plantea la estructuración del ensayo en forma de franjas en lugar del tradicional microarray, generando una señal periódica sinusoidal al ser escaneadas. Al analizar dicha señal en dominio de frecuencias, ésta se concentra en un pico a la frecuencia del ensayo, mientras que la mayor parte del ruido aparece a frecuencias mucho más altas. Inicialmente se quería reducir al máximo el ruido, para diferenciar las interacciones moleculares en formato label free. Sin embargo, los ensayos realizados con discos DVD no generaron suficiente señal, teniendo que recurrir en esta ocasión al marcaje para la cuantificación de inmunoglobulinas G y de caseína. Pese a ello, la metodología desarrollada también se puede aplicar en biosensores tipo label-free, reduciendo el ruido y mejorando su sensibilidad. El capítulo 3 se centra en el desarrollo de sustratos interferométricos multicapa que varían la intensidad de la luz reflejada al realizar un ensayo analítico en su superficie. Los sustratos fueron fabricados utilizando los materiales que componen los DVD-RW, depositados en capas de espesor controlado con el fin de obtener la máxima respuesta. A su vez, se diseñaron de tal forma que uno de ellos disminuya la intensidad del haz reflejado como respuesta a las interacciones moleculares, mientras que el otro la aumenta. El trabajo incluye la utilización de principios y materiales de la tecnología de disco compacto para el desarrollo del sistema de detección. Para ello, se emplea el cabezal de un lector de DVD, ya que dispone de un láser y de todos los elementos ópticos necesarios para el escaneado vertical. Con este sistema se cuantifican con éxito y sin marcaje inmunoglobulinas G y sulfasalazina, una macromolécula y un fármaco de masa molecular reducida. El capítulo 4 consiste en la fabricación de un cristal fotónico utilizando la estructura de los discos compactos cubiertos con una película de óxido de titanio. Se han estudiado las propiedades físico-químicas de estos sustratos y se han caracterizado sus propiedades fotónicas. Todo ello está en concordancia con los resultados obtenido mediante simulaciones. Para interrogar los cristales fotónicos fueron necesarios una fuente de luz blanca y un espectrofotómetro, además de los elementos ópticos necesarios / [CA] En aquesta tesi s'ha abordat el desenvolupament de biosensors òptics label-free, basats en tecnologia de disc compacte, permetent així abaratir i simplificar la seua fabricació. El treball dut a terme ha consistit en estudiar diferents propietats fisicoquímiques desenvolupades per diversos materials. Això ha permès obtenir sistemes compactes i accessibles, capaços de sensar, amb bones prestacions analítiques, en diferents escenaris. En el capítol 1 es presenta un estudi d'inhibició enzimàtica sobre discos Blu-ray com a plataforma d'assaig per al cribratge de fàrmacs. Per a això, s'immobilitza de manera orientada una glicoenzima de la família de les peroxidases sobre la superfície del disc, i la seua activitat es relaciona amb els compostos a garbellar. Després d'assajar cada compost, es determina el grau d'inhibició enzimàtica mitjançant l'addició d'un substrat. La quantitat de producte obtingut, inversament proporcional al potencial inhibitori del compost en estudi, és quantificat amb un lector de discos que registra les variacions en la intensitat del làser reflectit degudes al producte enzimàtic. Això permet realitzar més de 1700 assajos simultanis en un únic disc Blu-ray el que mostra el seu potencial en anàlisi massiva d'alt rendiment. A més, es planteja una estratègia basada en hipersuperficies per a l'anàlisi de l'elevada quantitat de dades que es generen en les etapes del procés de descobriment de fàrmacs. En el capítol 2 s'aborda l'estudi d'una metodologia per reduir el soroll generat en la lectura de resultats obtinguts amb biosensors òptics, millorant així la seua sensibilitat. Per a això, es planteja l'estructuració de l'assaig en forma de franges en lloc del tradicional microarray, generant un senyal periòdic sinusoïdal en ser escanejades. En analitzar aquest senyal en domini de freqüències, aquesta es concentra en un pic a la freqüència de l'assaig, mentre que la major part del soroll apareix a freqüències molt més altes. Inicialment es volia reduir al màxim el soroll, per diferenciar les interaccions moleculars en format label-free. No obstant això, els assajos realitzats amb discos DVD no van generar prou senyal, havent de recórrer en aquesta ocasió al marcatge per a la quantificació d'immunoglobulines G i de caseïna. Malgrat això, la metodologia desenvolupada també es pot aplicar en biosensors tipus label-free, reduint el soroll i millorant la seua sensibilitat. El capítol 3 es centra en el desenvolupament de substrats interferometrics multicapa que varien la intensitat de la llum reflectida en realitzar un assaig analític en la seua superfície. Els substrats van ser fabricats utilitzant els materials que componen els DVD-RW, dipositats en capes de gruix controlat per tal d'obtenir la màxima resposta. Al seu torn, es van dissenyar de tal manera que un d'ells disminueixi la intensitat del feix reflectit com a resposta a les interaccions moleculars, mentre que l'altre l'augmenta. El treball inclou la utilització de principis i materials de la tecnologia de disc compacte per al desenvolupament del sistema de detecció. Per a això, es va utilitzar el capçal d'un lector de DVD, ja que disposa d'un làser i de tots els elements òptics necessaris per a l'escanejat vertical. Amb aquest sistema es quantifiquen amb èxit i sense marcatge immunoglobulines G i sulfasalazina, un macromolècula i un fàrmac de massa molecular reduïda. El capítol 4 consisteix en la fabricació d'un cristall fotònic utilitzant l'estructura dels discos compactes coberts amb una pel·lícula d'òxid de titani. S'han estudiat les propietats fisicoquímiques d'aquests substrats i s'han caracteritzat les propietats fotòniques. Tot això està en concordança amb els resultats obtingut mitjançant simulacions. Per interrogar els cristalls fotònics van ser necessaris una font de llum blanca i un espectrofotòmetre, a més dels elements òptics necessaris per guiar la llum. / [EN] In this thesis the development of label-free optical biosensors, based on compact disc technology, has been approached, thus making their manufacture cheaper and simpler. The work carried out has consisted of studying different physical-chemical properties manifested with several materials. This has allowed to obtain compact and accessible systems, capable of sensing with a great analytical performance in different scenarios. Chapter 1 presents an enzymatic inhibition study on Blu-ray discs as a test platform for drug screening. For this purpose, a glycoenzyme of the peroxidase family is immobilized on the surface of the disc whose activity is related to the compounds to be screened. After testing each compound, the degree of enzymatic inhibition is determined by adding the enzymatic substrate. The amount of product obtained is inversely proportional to the inhibitory potential of the compound, and is quantified with a disk reader that records the variations in the intensity of the reflected laser beam due to the enzymatic product. In addition, more than 1700 tests are performed on a single Blu-ray disc as proof of concept for application in high performance analysis and a hypersurface based strategy is proposed for the analysis of the large amount of data generated in the stages of the drug discovery process. Chapter 2 deals with the study of a methodology to reduce noise generated in the reading of results obtained with optical biosensors, hence improving their sensitivity. For this purpose, the structure of the test is proposed in the form of stripes instead of the traditional microarray, generating a sinusoidal periodic signal when they are scanned. When analysing this signal in frequency domain, it is concentrated in a peak at the frequency of the test, while most of the noise appears at much higher frequencies. Initially, the aim was to reduce noise as much as possible in order to differentiate molecular interactions in a label-free format. However, the tests carried out on a DVD did not generate enough signal, having to resort to labelling on this occasion for the quantification of immunoglobulins G and casein. Nevertheless, the methodology developed can be applied to label-free biosensors, reducing noise and improving sensitivity. Chapter 3 focuses on the development of multilayer interferometric substrates that vary the intensity of reflected light when performing an analytical test on their surface. The substrates were manufactured using the materials that make up the DVD-RW, deposited in layers of controlled thickness in order to obtain maximum response. At the same time, they were designed in such a way that one of them decreased the intensity of the reflected beam as a response to molecular interactions, while the other increased it. The work includes the use of principles and materials from compact disc technology for the development of the detection system. For this, the head of a DVD reader is used, as it has a laser and all the optical elements necessary for vertical scanning. With this system, immunoglobulins G and sulfasalazine, a macromolecule and a drug with reduced molecular mass are successfully quantified without labelling. Chapter 4 consists of the fabrication of a photonic crystal using the structure of the compact discs covered with a titanium oxide layer. The physical-chemical properties of these substrates have been studied and their photonic properties have been characterized. All this is in accordance with the results obtained through simulations. To interrogate the photonic crystals, a white light source and a spectrophotometer were needed, as well as the optical elements necessary to guide the light. / Sancho Fornés, G. (2019). Integración de diferentes fenómenos fotónicos en tecnología de disco compacto para el desarrollo de biosensores label-free [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/124819 / Compendio

Food labels are imperative in consumers‟ decision-making process of packaged food products as they communicate important information such as expiry dates, nutrition information and information about allergies to the consumer. Especially during a first-time purchase, consumers rely on food labels to assist them in making their product choice easier. In the heterogeneous context of South Africa, consumers‟ product needs vary and one may assume that consumer needs in terms of food label information differ. Although food labelling is regulated in South Africa, it is still important that consumers are satisfied with labels due to their significant communicative function. However, to the knowledge of the author, little previous research exists on South African consumers‟ satisfaction with food labels. Therefore, this study aimed to explore and describe consumers‟ satisfaction with food labels based on a typical in-store encounter. The confirmation/disconfirmation paradigm had been used as theoretical foundation in this study and consumers‟ expectations and performance judgement of food labels were therefore explored and compared within the confirmation/disconfirmation paradigm. This study furthermore aimed to explore the influence of food labels on consumers‟ product choice as well as to determine the influence of demographic characteristics on consumers‟ expectations and performance judgement of food labels. Lastly, this study aimed to make recommendations to food regulators and manufacturers on how existing food labels could be improved in order to enhance consumer satisfaction. Based on the literature, satisfaction with food labels might be influenced by the information on food labels such as ingredient lists, expiry dates and nutrition information as well as attributes of food labels such as the readability, understandability, credibility and adequacy. Exploratory factor analysis used in the present study indicated that the information on food labels can be classified as either primary (ingredient list, expiry date, health and nutrition information, information about allergies and quality guarantee) or secondary (name of manufacturer, well-known logos or symbols, country of origin or geographical region, usage instructions and number of servings). A quantitative research method by means of a survey approach was used in this study over a period of three weeks. A total of 400 self-administered questionnaires were distributed at office buildings and business premises in the urban Gauteng Province in September 2010 by means of a non-probability sampling method. A total of 279 useful questionnaires were retrieved and data analysis was performed by Statistical Consultations Services of the North-West University using SPSS (Statistical Package for Social Sciences). Results show that respondents were only partially satisfied with food labels as they were satisfied with secondary information, but dissatisfied with primary information as well as with label attributes. The results furthermore show that primary information tended to be more likely to influence respondents‟ product choice than secondary information. In addition, results show that demographics had little influence on respondents‟ expectations and performance judgement of food labels. Based on the findings of this study, recommendations can be made to regulators and manufacturers on how consumer satisfaction with existing food labels can be improved. Recommendations include the improvement of the overall readability, understandability, credibility as well as adequacy of food labels. Especially primary information and the way it gets portrayed should be considered for improvement to increase consumer satisfaction. / Thesis (M. Consumer Science)--North-West University, Potchefstroom Campus, 2011

L'apprentissage multi-label est un problème d'apprentissage supervisé où chaque instance peut être associée à plusieurs labels cibles simultanément. Il est omniprésent dans l'apprentissage automatique et apparaît naturellement dans de nombreuses applications du monde réel telles que la classification de documents, l'étiquetage automatique de musique et l'annotation d'images. Nous discutons d'abord pourquoi les algorithmes multi-label de l'etat-de-l'art utilisant un comité de modèle souffrent de certains inconvénients pratiques. Nous proposons ensuite une nouvelle stratégie pour construire et agréger les modèles ensemblistes multi-label basés sur k-labels. Nous analysons ensuite en profondeur l'effet de l'étape d'agrégation au sein des approches ensemblistes multi-label et étudions comment cette agrégation influece les performances de prédictive du modèle enfocntion de la nature de fonction cout à optimiser. Nous abordons ensuite le problème spécifique de la selection de variables dans le contexte multi-label en se basant sur le paradigme ensembliste. Trois méthodes de sélection de caractéristiques multi-label basées sur le paradigme des forêts aléatoires sont proposées. Ces méthodes diffèrent dans la façon dont elles considèrent la dépendance entre les labels dans le processus de sélection des varibales. Enfin, nous étendons les problèmes de classification et de sélection de variables au cadre d'apprentissage semi-supervisé. Nous proposons une nouvelle approche de sélection de variables multi-label semi-supervisée basée sur le paradigme de l'ensemble. Le modèle proposé associe des principes issues de la co-training en conjonction avec une métrique interne d'évaluation d'importnance des varaibles basée sur les out-of-bag. Testés de manière satisfaisante sur plusieurs données de référence, les approches développées dans cette thèse sont prometteuses pour une variété d'ap-plications dans l'apprentissage multi-label supervisé et semi-supervisé. Testés de manière satisfaisante sur plusieurs jeux de données de référence, les approches développées dans cette thèse affichent des résultats prometteurs pour une variété domaine d'applications de l'apprentissage multi-label supervisé et semi-supervisé / Multi-label learning is a specific supervised learning problem where each instance can be associated with multiple target labels simultaneously. Multi-label learning is ubiquitous in machine learning and arises naturally in many real-world applications such as document classification, automatic music tagging and image annotation. In this thesis, we formulate the multi-label learning as an ensemble learning problem in order to provide satisfactory solutions for both the multi-label classification and the feature selection tasks, while being consistent with respect to any type of objective loss function. We first discuss why the state-of-the art single multi-label algorithms using an effective committee of multi-label models suffer from certain practical drawbacks. We then propose a novel strategy to build and aggregate k-labelsets based committee in the context of ensemble multi-label classification. We then analyze the effect of the aggregation step within ensemble multi-label approaches in depth and investigate how this aggregation impacts the prediction performances with respect to the objective multi-label loss metric. We then address the specific problem of identifying relevant subsets of features - among potentially irrelevant and redundant features - in the multi-label context based on the ensemble paradigm. Three wrapper multi-label feature selection methods based on the Random Forest paradigm are proposed. These methods differ in the way they consider label dependence within the feature selection process. Finally, we extend the multi-label classification and feature selection problems to the semi-supervised setting and consider the situation where only few labelled instances are available. We propose a new semi-supervised multi-label feature selection approach based on the ensemble paradigm. The proposed model combines ideas from co-training and multi-label k-labelsets committee construction in tandem with an inner out-of-bag label feature importance evaluation. Satisfactorily tested on several benchmark data, the approaches developed in this thesis show promise for a variety of applications in supervised and semi-supervised multi-label learning

O E. grandis x E. camaldulensis possui características favoráveis de adaptação à seca, conferidas pelo E. camaldulensis e qualidade da madeira para papel e celulose, conferida pelo E. grandis. Esta adaptação à seca está relacionada a fatores fisiológicos e também moleculares, expressos em sua proteoma e metaboloma, que se alteram na presença do estresse. Objetiva-se neste trabalho estudar as respostas fisiológicas, proteômicas e metabolômicas (metabólitos primários) diferencialmente expressos em folhas de Eucalyptus submetidas ao déficit hídrico. Dois genótipos de E. grandis x E. camaldulensis, sendo um tolerante (T) e um susceptível (S) ao déficit hídrico foram submetidos à 100% e 30% da capacidade de campo (CC), para as plantas bem irrigadas e as em déficit hídrico, respectivamente. Os tratamentos foram chamados de T100, T30, S100 e S30 para os diferentes genótipos, T e S, submetidos a diferentes CC, 100% e 30%. Estas plantas foram avaliadas fisiologicamente com auxílio do equipamento Infrared Gas Analyzer (IRGA). Foram empregadas técnicas de proteômica quantitativa, label-free e shotgun, através do uso de UPLC-MSE. O estudo de metabolômica ocorreu através da utilização do GC x GC-TOF/MS. Os dados de proteômica foram processados no programa Protein Lynx Global Server (PLGS) e ExpressionE, através das análises comparativas S100 vs S30 e T100 vs T30, e dos metabólitos primários nos programas ChromaTOF e MetaboAnalyst. Foi possível observar que o T100 apresentou menor taxa fotossintética e condutância estomática do que o S100. Ambos os genótipos apresentaram taxas fotossintéticas e condutância estomática muito menores a 30% da CC do que a 100% da CC. A análise proteômica identificou um total de 397, 305, 366, 309 proteínas nos tratamentos S100, S30, T100 e T30 respectivamente. As análises comparativas por PLGS constataram que houve um aumento no número de proteínas diferencialmente expressas na presença do déficit hídrico. Cinco processos biológicos que apresentaram um aumento no número de proteínas diferencialmente expressas na presença do déficit hídrico foram: homeostase celular, fotossíntese, resposta ao estímulo abiótico, resposta ao estresse e morte celular. Três vias biológicas que apresentaram a participação de muitas enzimas identificadas, relacionadas a processos fotossintéticos, foram: fixação de carbono em organismos fotossintéticos, ciclo TCA e glicólise/gluconeogênese. O déficit hídrico diminuiu o número de proteínas diferencialmente expressas relacionadas ao processo metabólico de compostos contendo bases nucleares, regulação biológica e processo biossintético, que estão relacionados ao crescimento, desenvolvimento e manutenção dos processos vitais das plantas. Em relação à análise metabolômica foram identificados um total de 93, 94, 90 e 91 metabólitos primários nos tratamentos S100, S30, T100 e T30, respectivamente. Utilizando o programa Metaboanalyst, foi possível identificar os 15 metabólitos que mais contribuíram para a separação dos tratamentos, com maiores \"VIP scores\", sendo alguns responsivos ao déficit hídrico. A via da purina e arginina foi identificada como a mais frequente dentre os metabólitos identificados com VIP score ≥ 1,5. / The E. grandis x E. camaldulensis has favourable characteristics of adaptation to drought, conferred by E. camaldulensis and quality of wood for pulp and paper, conferred by E. grandis. This adaptation to drought is related to physiological factors and also expressed in their molecular proteome and metabolome, which change in the presence of stress. The aim of this work was to study the physiological responses, proteomics and metabolomics (primary metabolites) differentially expressed in leaves of Eucalyptus under drought. Two genotypes of E. grandis x E. camaldulensis, a tolerant (T) and a susceptible (S) to drought stress, were subjected to 100% and 30% of field capacity (FC), for the well-watered plants and drought stressed plants, respectively. The treatments were called T100, T30, S100 and S30 for different genotypes, T and S, submitted to different FC, 100% and 30%. These plants were evaluated physiologically using the Infrared Gas Analyzer (IRGA). Label-free and shotgun quantitative proteomics were realized using UPLC-MSE. The metabolomics study was carried out using GC x GC-TOF/MS mass spectrometer. The proteomics data were processed using the Protein Lynx Global Server program (PLGS) and ExpressionE program, through comparative analyses S100 vs S30 and T100 vs S30, and primary metabolites in ChromaTOF and MetaboAnalyst programs. It was observed that T100 had lower photosynthetic rate and stomatal conductance than S100. Both genotypes showed stomatal conductance and photosynthetic rates lower at 30% of FC than at 100% of FC. The proteomic analysis identified a total of 397, 305, 366, 309 proteins in the treatments S100, S30, T100 and T30 respectively. Comparative PLGS analyses showed an increase in the number of differentially expressed proteins under drought stress. The five biological processes that showed an increase in the number of differentially expressed proteins under drought stress were: cellular homeostasis, photosynthesis, response to abiotic stimulus, response to stress and cell death. The three biological pathways that had the participation of many identified enzymes, which are related to photosynthetic processes, were: carbon fixation in photosynthetic organisms, TCA cycle and glycolysis / gluconeogenesis. The drought reduced the number of differentially expressed proteins related to the metabolism of compounds containing nuclear bases, biological regulation and biosynthetic process, which were related to growth, development and maintenance of the vital processes of plants. The metabolomic analysis identified a total of 93, 94, 90 and 91 primary metabolites in the treatments S100, S30, T100 and T30, respectively. Using Metaboanalyst program, it was possible to identify 15 metabolites that contributed to the separation of treatments with higher \"VIP scores\", some of these are responsive to drought. The purine and arginine pathway was identified as the most frequent among the metabolites identified with VIP score ≥ 1.5.

Métodos tradicionais de aprendizado supervisionado, chamados de aprendizado monorrótulo, consideram que cada exemplo do conjunto de dados rotulados está associado a um único rótulo. No entanto, existe uma crescente quantidade de aplicações que lidam com exemplos que estão associados a múltiplos rótulos. Essas aplicações requerem métodos de aprendizado multirrótulo. Esse cenário de aprendizado introduz novos desafios que demandam abordagens diferentes daquelas tradicionalmente utilizadas no aprendizado monorrótulo. O custo associado ao processo de rotulação de exemplos, um problema presente em aprendizado monorrótulo, é ainda mais acentuado no contexto multirrótulo. O desenvolvimento de métodos para reduzir esse custo representa um desafio de pesquisa nessa área. Além disso, novos métodos de aprendizado também devem ser desenvolvidos para, entre outros objetivos, considerar a dependência de rótulos: uma nova característica presente no aprendizado multirrótulo. Há um consenso na comunidade de que métodos de aprendizado multirrótulo têm a capacidade de usufruir de melhor eficácia preditiva quando considerada a dependência de rótulos. Os principais objetivos deste trabalho estão relacionados a esses desafios: reduzir o custo do processo de rotulação de exemplos; e desenvolver métodos de aprendizado que explorem a dependência de rótulos. No primeiro caso, entre outras contribuições, um novo método de aprendizado ativo, chamado score dev, é proposto para reduzir os custos associados ao processo de rotulação multirrótulo. Resultados experimentais indicam que o método score dev é superior a outros métodos em vários domínios. No segundo caso, um método para identificar dependência de rótulos, chamado UBC, é proposto, bem como o BR+, um método para explorar essa característica. O método BR+ apresenta resultados superiores a métodos considerados estado da arte / Traditional supervised learning methods, called single-label learning, consider that each example from a labeled dataset is associated with only one label. However, an increasing number of applications deals with examples that are associated with multiple labels. These applications require multi-label learning methods. This learning scenario introduces new challenges and demands approaches that are different from those traditionally used in single-label learning. The cost of labeling examples, a problem in single-label learning, is even higher in the multi-label context. Developing methods to reduce this cost represents a research challenge in this area. Moreover, new learning methods should also be developed to, among other things, consider the label dependency: a new characteristic present in multi-label learning problems. Furthermore, there is a consensus in the community that multi-label learning methods are able to improve their predictive performance when label dependency is considered. The main aims of this work are related to these challenges: reducing the cost of the labeling process; and developing multi-label learning methods to explore label dependency. In the first case, as well as other contributions, a new multi-label active learning method, called score dev, is proposed to reduce the multi-labeling processing costs. Experimental results show that score dev outperforms other methods in many domains. In the second case, a method to identify label dependency, called UBC, is proposed, as well as BR+, a method to explore this characteristic. Results show that the BR+ method outperforms other state-of-the-art methods

Food labels are imperative in consumers‟ decision-making process of packaged food products as they communicate important information such as expiry dates, nutrition information and information about allergies to the consumer. Especially during a first-time purchase, consumers rely on food labels to assist them in making their product choice easier. In the heterogeneous context of South Africa, consumers‟ product needs vary and one may assume that consumer needs in terms of food label information differ. Although food labelling is regulated in South Africa, it is still important that consumers are satisfied with labels due to their significant communicative function. However, to the knowledge of the author, little previous research exists on South African consumers‟ satisfaction with food labels. Therefore, this study aimed to explore and describe consumers‟ satisfaction with food labels based on a typical in-store encounter. The confirmation/disconfirmation paradigm had been used as theoretical foundation in this study and consumers‟ expectations and performance judgement of food labels were therefore explored and compared within the confirmation/disconfirmation paradigm. This study furthermore aimed to explore the influence of food labels on consumers‟ product choice as well as to determine the influence of demographic characteristics on consumers‟ expectations and performance judgement of food labels. Lastly, this study aimed to make recommendations to food regulators and manufacturers on how existing food labels could be improved in order to enhance consumer satisfaction. Based on the literature, satisfaction with food labels might be influenced by the information on food labels such as ingredient lists, expiry dates and nutrition information as well as attributes of food labels such as the readability, understandability, credibility and adequacy. Exploratory factor analysis used in the present study indicated that the information on food labels can be classified as either primary (ingredient list, expiry date, health and nutrition information, information about allergies and quality guarantee) or secondary (name of manufacturer, well-known logos or symbols, country of origin or geographical region, usage instructions and number of servings). A quantitative research method by means of a survey approach was used in this study over a period of three weeks. A total of 400 self-administered questionnaires were distributed at office buildings and business premises in the urban Gauteng Province in September 2010 by means of a non-probability sampling method. A total of 279 useful questionnaires were retrieved and data analysis was performed by Statistical Consultations Services of the North-West University using SPSS (Statistical Package for Social Sciences). Results show that respondents were only partially satisfied with food labels as they were satisfied with secondary information, but dissatisfied with primary information as well as with label attributes. The results furthermore show that primary information tended to be more likely to influence respondents‟ product choice than secondary information. In addition, results show that demographics had little influence on respondents‟ expectations and performance judgement of food labels. Based on the findings of this study, recommendations can be made to regulators and manufacturers on how consumer satisfaction with existing food labels can be improved. Recommendations include the improvement of the overall readability, understandability, credibility as well as adequacy of food labels. Especially primary information and the way it gets portrayed should be considered for improvement to increase consumer satisfaction. / Thesis (M. Consumer Science)--North-West University, Potchefstroom Campus, 2011

Objetivos: Descrever o uso e determinar a prevalência de medicamentos potencialmente perigosos e de uso off label e não aprovados em prescrições de unidades de pediatria geral de um hospital universitário no sul do Brasil. Método: Estudo transversal, realizado de novembro de 2007 a janeiro de 2008, envolvendo pacientes até 14 anos de idade, com período de internação superior a 24 horas. Pacientes de unidades de terapia intensiva e oncologia pediátrica foram excluídos. A classificação quanto aos critérios de aprovação da Food and Drug Administration foi realizada pela fonte terciária DrugDex-Micromedex e a classificação dos potencialmente perigosos, pelo Institute for Safe Medication Practices. Resultados e discussão: No período de estudo foram analisadas 342 prescrições de 342 pacientes. O sexo masculino foi o mais freqüente (57%) e mais da metade dos pacientes já apresentavam doenças crônicas à internação. Analgésicos foi a classe terapêutica mais prescrita (26,9%) e entre os off label, os antiespasmódicos (31,5%) foram os mais prevalentes. Das prescrições analisadas, aproximadamente 39% tiveram pelo menos um medicamento de uso off label prescrito, principalmente em relação à indicação terapêutica (38,4%) e à idade (21,9 %), e 11,8% dos pacientes fizeram uso de fármacos não aprovados. Do total de itens (2026), cerca de 6% foram classificados como potencialmente perigosos, destacando-se os analgésicos opióides (35%). Não houve relação de associação entre medicamentos de uso off label e os potencialmente perigosos. Conclusão: As frequências encontradas de medicamentos off label e não aprovados estão de acordo com a literatura e podem ser consideradas elevadas. Os potencialmente perigosos, apesar da baixa prevalência, oferecem risco pelos efeitos prejudiciais que possam vir a causar nos pacientes. Assim, os medicamentos em destaque neste estudo representam uma preocupação constante em hospitais. / Objectives: Describe the use and determine the prevalence of high-alert medications, off label use and unlicensed drugs in prescriptions of general pediatric units of a university hospital in southern Brazil. Method: Cross-sectional study, performed from November 2007 to January 2008, involving patients up to 14 years of age, with admission period over 24 hours. Patients of intensive care and pediatric oncology units were excluded. The classification regarding the Food and Drug Administration approval criteria was performed according to the DrugDex-Micromedex tertiary source and the classification of high-alert medications according to the Institute for Safe Medication Practices. Results e discussion: In the study period, 342 prescriptions were analyzed. Males were more frequent (57%) and over half of the patients already presented chronic diseases for admission. Analgesic drugs were the most frequently prescribed therapeutic class of drugs (26.9%) and among the off-label drugs, antispasmodic drugs (31.5%) were the most prevalent. Around 39% of the analyzed prescriptions had at least one off-label use drug, especially in relation to therapeutic indication (38.4%) and age (21.9%), and 11.8% of the patients received unlicensed drugs. About 6% of the total items (2026) were classified as high-alert medications, such as opioid analgesic drugs (35%). No relation of association was observed between off-label use and high-alert medications. Conclusion: The frequency analyses found of off-label and unlicensed drugs are according to the literature and can be considered as high. The high-alert medications, although of low prevalence, offer risks due to negative effects that can occur in patients. Then, the drugs highlighted in this study constitute a constant concern in hospitals.

Objetivos: Descrever o uso e determinar a prevalência de medicamentos potencialmente perigosos e de uso off label e não aprovados em prescrições de unidades de pediatria geral de um hospital universitário no sul do Brasil. Método: Estudo transversal, realizado de novembro de 2007 a janeiro de 2008, envolvendo pacientes até 14 anos de idade, com período de internação superior a 24 horas. Pacientes de unidades de terapia intensiva e oncologia pediátrica foram excluídos. A classificação quanto aos critérios de aprovação da Food and Drug Administration foi realizada pela fonte terciária DrugDex-Micromedex e a classificação dos potencialmente perigosos, pelo Institute for Safe Medication Practices. Resultados e discussão: No período de estudo foram analisadas 342 prescrições de 342 pacientes. O sexo masculino foi o mais freqüente (57%) e mais da metade dos pacientes já apresentavam doenças crônicas à internação. Analgésicos foi a classe terapêutica mais prescrita (26,9%) e entre os off label, os antiespasmódicos (31,5%) foram os mais prevalentes. Das prescrições analisadas, aproximadamente 39% tiveram pelo menos um medicamento de uso off label prescrito, principalmente em relação à indicação terapêutica (38,4%) e à idade (21,9 %), e 11,8% dos pacientes fizeram uso de fármacos não aprovados. Do total de itens (2026), cerca de 6% foram classificados como potencialmente perigosos, destacando-se os analgésicos opióides (35%). Não houve relação de associação entre medicamentos de uso off label e os potencialmente perigosos. Conclusão: As frequências encontradas de medicamentos off label e não aprovados estão de acordo com a literatura e podem ser consideradas elevadas. Os potencialmente perigosos, apesar da baixa prevalência, oferecem risco pelos efeitos prejudiciais que possam vir a causar nos pacientes. Assim, os medicamentos em destaque neste estudo representam uma preocupação constante em hospitais. / Objectives: Describe the use and determine the prevalence of high-alert medications, off label use and unlicensed drugs in prescriptions of general pediatric units of a university hospital in southern Brazil. Method: Cross-sectional study, performed from November 2007 to January 2008, involving patients up to 14 years of age, with admission period over 24 hours. Patients of intensive care and pediatric oncology units were excluded. The classification regarding the Food and Drug Administration approval criteria was performed according to the DrugDex-Micromedex tertiary source and the classification of high-alert medications according to the Institute for Safe Medication Practices. Results e discussion: In the study period, 342 prescriptions were analyzed. Males were more frequent (57%) and over half of the patients already presented chronic diseases for admission. Analgesic drugs were the most frequently prescribed therapeutic class of drugs (26.9%) and among the off-label drugs, antispasmodic drugs (31.5%) were the most prevalent. Around 39% of the analyzed prescriptions had at least one off-label use drug, especially in relation to therapeutic indication (38.4%) and age (21.9%), and 11.8% of the patients received unlicensed drugs. About 6% of the total items (2026) were classified as high-alert medications, such as opioid analgesic drugs (35%). No relation of association was observed between off-label use and high-alert medications. Conclusion: The frequency analyses found of off-label and unlicensed drugs are according to the literature and can be considered as high. The high-alert medications, although of low prevalence, offer risks due to negative effects that can occur in patients. Then, the drugs highlighted in this study constitute a constant concern in hospitals.

Objetivos: Descrever o uso e determinar a prevalência de medicamentos potencialmente perigosos e de uso off label e não aprovados em prescrições de unidades de pediatria geral de um hospital universitário no sul do Brasil. Método: Estudo transversal, realizado de novembro de 2007 a janeiro de 2008, envolvendo pacientes até 14 anos de idade, com período de internação superior a 24 horas. Pacientes de unidades de terapia intensiva e oncologia pediátrica foram excluídos. A classificação quanto aos critérios de aprovação da Food and Drug Administration foi realizada pela fonte terciária DrugDex-Micromedex e a classificação dos potencialmente perigosos, pelo Institute for Safe Medication Practices. Resultados e discussão: No período de estudo foram analisadas 342 prescrições de 342 pacientes. O sexo masculino foi o mais freqüente (57%) e mais da metade dos pacientes já apresentavam doenças crônicas à internação. Analgésicos foi a classe terapêutica mais prescrita (26,9%) e entre os off label, os antiespasmódicos (31,5%) foram os mais prevalentes. Das prescrições analisadas, aproximadamente 39% tiveram pelo menos um medicamento de uso off label prescrito, principalmente em relação à indicação terapêutica (38,4%) e à idade (21,9 %), e 11,8% dos pacientes fizeram uso de fármacos não aprovados. Do total de itens (2026), cerca de 6% foram classificados como potencialmente perigosos, destacando-se os analgésicos opióides (35%). Não houve relação de associação entre medicamentos de uso off label e os potencialmente perigosos. Conclusão: As frequências encontradas de medicamentos off label e não aprovados estão de acordo com a literatura e podem ser consideradas elevadas. Os potencialmente perigosos, apesar da baixa prevalência, oferecem risco pelos efeitos prejudiciais que possam vir a causar nos pacientes. Assim, os medicamentos em destaque neste estudo representam uma preocupação constante em hospitais. / Objectives: Describe the use and determine the prevalence of high-alert medications, off label use and unlicensed drugs in prescriptions of general pediatric units of a university hospital in southern Brazil. Method: Cross-sectional study, performed from November 2007 to January 2008, involving patients up to 14 years of age, with admission period over 24 hours. Patients of intensive care and pediatric oncology units were excluded. The classification regarding the Food and Drug Administration approval criteria was performed according to the DrugDex-Micromedex tertiary source and the classification of high-alert medications according to the Institute for Safe Medication Practices. Results e discussion: In the study period, 342 prescriptions were analyzed. Males were more frequent (57%) and over half of the patients already presented chronic diseases for admission. Analgesic drugs were the most frequently prescribed therapeutic class of drugs (26.9%) and among the off-label drugs, antispasmodic drugs (31.5%) were the most prevalent. Around 39% of the analyzed prescriptions had at least one off-label use drug, especially in relation to therapeutic indication (38.4%) and age (21.9%), and 11.8% of the patients received unlicensed drugs. About 6% of the total items (2026) were classified as high-alert medications, such as opioid analgesic drugs (35%). No relation of association was observed between off-label use and high-alert medications. Conclusion: The frequency analyses found of off-label and unlicensed drugs are according to the literature and can be considered as high. The high-alert medications, although of low prevalence, offer risks due to negative effects that can occur in patients. Then, the drugs highlighted in this study constitute a constant concern in hospitals.

Submitted by Cláudia Bueno (claudiamoura18@gmail.com) on 2016-04-05T17:29:19Z No. of bitstreams: 2 Tese - Maria Auxiliadora Andrade - 2005.pdf: 1009311 bytes, checksum: fc89542ce0a0fb7c6a73727f348fc5a1 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-04-06T11:11:10Z (GMT) No. of bitstreams: 2 Tese - Maria Auxiliadora Andrade - 2005.pdf: 1009311 bytes, checksum: fc89542ce0a0fb7c6a73727f348fc5a1 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2016-04-06T11:11:10Z (GMT). No. of bitstreams: 2 Tese - Maria Auxiliadora Andrade - 2005.pdf: 1009311 bytes, checksum: fc89542ce0a0fb7c6a73727f348fc5a1 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2006-09-16 / Two experiments were carried out to evaluate the use of quaternary ammonia on Salmonella Enteritidis inoculated in eggshell and its penetration capacities, verify the ability to infect the egg inoculated in eggshell, determine embryo mortality, infect hatched chicks and affect incubation parameters of two broiler lines. A total of 302 and 290 fertile eggs of Ross and ISA Label, respectively, were distributed in six treatments: eggs sanitized with placebo (Treatment 1- PC) quaternary ammonia inoculated with Salmonella Enteritidis (Treatment 2-PI); eggs non-sanitized and inoculated placebo (Treatment 3- NPC) with Salmonella Enteritidis (Treatment 4- NPI); eggs inoculated in allantoidal cavity with placebo (Treatment 5-CAC) or Salmonella Enteritidis (Treatment 6- CAI). Immediately after inoculation, the eggs were hatched and embryo mortality was evaluated after 96, 432 and 528 hours. The qualitative results were analyzed by non-parametric tests of chi-square and Kruskall-Wallis. The incubation parameters were not affected when the pathogen was inoculated in eggshell. It was observed that Salmonella Enteritidis inoculated in allantoidal cavity determined late embryo mortality in fast 17,02% and slow growing 13,04% lines, and eggs inoculated in allantoidal cavity originated chicks with high frequency of intestinal colonization by Salmonella Enteritidis of 76,67% and 26,67% Ross and ISA Label, respective. / Foram conduzidos dois experimentos para avaliar os efeitos de quaternários de amônia sobre Salmonella Enteritidis inoculados na casca e a capacidade de penetração deste patógeno na casca e para verificar sua habilidade em infectar os ovos inoculados pela casca e cavidade alantóide, determinar mortalidade embrionária, infectar os pintos eclodidos e afetar os parâmetros de incubação em duas linhagens de frango de corte. Utilizaram-se, respectivamente, 302 e 290 ovos férteis das linhagens Ross e ISA Label, distribuídos em seis tratamentos: ovos sanitizados e inoculados com o placebo (tratamento 1- PC) ou com quaternários de amônio inoculados na casca com Salmonella Enteritidis fagotipo 4 (tratamento 2-PI); ovos não sanitizados e inoculados na casca com placebo (tratamento 3-NPC) ou com Salmonella Enteritidis (tratamento 4-NPI); ovos inoculados na cavidade alantóide com placebo (tratamento 5-CAC) ou com Salmonella Enteritidis (tratamento 6-CAI). Imediatamente após a inoculação, os ovos foram incubados e a mortalidade embrionária avaliada após 96, 432 e 528 horas. As respostas qualitativas foram analisadas pelos testes não paramétricos de qui-quadrado e de Kruskal-Wallis. Constatou-se que a sanitização dos ovos não eliminou a Salmonella Enteritidis inoculada na casca sendo que o agente manteve-se viável na casca durante todo o período de incubação e migrou para o interior dos ovos em três das 20 amostras analisadas. Os parâmetros de incubação não foram afetados quando o patógeno foi inoculado na casca. Constatou-se também que a Salmonella Enteritidis inoculada na cavidade alantóide determinou mortalidade embrionária tardia nas linhagens Ross de 17,02% e ISA Label de 13,04%, assim como os ovos inoculados nesta cavidade originaram pintos com maior freqüência de colonização intestinal pela Salmonella Enteritidis de 76,67% e 26,67% para Ross e ISA Label, respectivamente.