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Global Diatom Biodiversity : An Assessment Using Metabarcoding Approach / Diatomées biodiversité mondiale : une évaluation utilisant une approche metabarcodingMalviya, Shruti 20 May 2015 (has links)
Les diatomées (Stramenopiles, Bacillariophyceae) jouent un rôle important sur le plan écologique et sont l'un des groupes phytoplanctoniques les plus divers, avec environ 1800 espèces planctoniques estimées. Bien que largement étudiées, leurs modèles de diversité et de distribution biogéographique ne sont pas bien connus. L'avènement du séquençage de l'ADN à haut débit a révolutionné les études de biodiversité moléculaire facilitant la compréhension de la biogéographie, de la structure des communautés et des processus écologiques. Les deux principaux objectifs de cette thèse sont (1) d'enquêter sur les modèles de la biodiversité mondiale et la structure des communautés de diatomées planctoniques à travers les océans du monde, et (2) de comprendre les mécanismes et processus déterminants la structure de la communauté. Cette thèse présente également une première tentative de discerner la répartition des espèces rares dans les communautés de protistes. L'étude a été réalisée en utilisant les données de metabarcoding générées à partir des échantillons biologiques et des données environnementales associées recueillies au cours de la campagne Tara Oceans (2009-2013), une circumnavigation globale couvrant toutes les principales provinces océaniques. Le matériel d’étude pour cette thèse est constitué d’un total de 12 millions de séquences de la sous unité V9 du 18S ribosomal (barcode), récoltées à partir de 46 stations soit 293 échantillons. Basée sur 63371 metabarcodes de diatomées uniques, cette étude présente une évaluation approfondie de la distribution mondiale des diatomées et de leur diversité. Les analyses révèlent des faits marquants liées à la biogéographie des diatomées, par exemple une nouvelle estimation du nombre total d'espèces de diatomées planctoniques, une diversité considérable inconnue, une diversité exceptionnellement élevée en haute mer, et des patrons de diversité complexes entre les provinces océaniques. La thèse examine ensuite les facteurs qui déterminent les modèles de bêta-diversité. Les résultats suggèrent que les diatomées sont des communautés structurées et réglementées par l'hétérogénéité de l'environnement et des processus spatiaux. Néanmoins, la majorité de la variation totale dans la composition de la communauté ne peut être expliquée ni par les facteurs environnementaux, ni par les distances spatiales, ce qui justifie les analyses futures se concentrant sur les interactions biologiques, les événements historiques, et d'autres facteurs qui ne sont pas considérés. La thèse décrit en outre une approche pour caractériser les clusters significativement associés de ribotypes concomitants. Enfin, une étude préliminaire de communautés de protistes fractionnées par taille révèle que la queue (de leurs distributions rang abondance) semble suivre un comportement en loi de puissance dans presque toutes les communautés de protistes. Cette observation peut indiquer un mécanisme universel potentiel qui peut expliquer l'organisation de communautés planctoniques marines. De façon générale, ce travail présent une perspective globale et complète de la distribution et de la diversité des diatomées dans les océans du monde. La thèse propose un cadre global pour l'évaluation de la diversité mondiale basée sur le metabarcoding, qui pourra être utilisé pour étudier la distribution et la diversité des autres lignées taxonomiques. Par conséquent, ce travail fournit un point de référence pour explorer comment les communautés microbiennes feront face à la variation des conditions environnementales. / Diatoms (Stramenopiles, Bacillariophyceae) are an ecologically important and one of the most diverse phytoplanktonic groups, with an estimated ~1,800 marine planktonic species. Although widely studied, their diversity and biogeographic distribution patterns are not well known. The advent of high-throughput DNA sequencing has revolutionized molecular biodiversity studies facilitating the understanding of biogeography, community assembly and ecological processes. The two major goals of this thesis are (1) to investigate global biodiversity patterns and structure of marine planktonic diatom communities across the world’s oceans, and (2) to understand the mechanisms and processes determining their community structure and assembly. This thesis also presents an initial attempt to discern the distribution of rare species in protist communities. The study was conducted using the metabarcoding data generated from the biological samples and associated environmental data collected during the Tara Oceans (2009-2013) global circumnavigation covering all major oceanic provinces. A total of ~12 million diatom V9-18S rDNA tags from 46 sampling stations, constituting 293 size fractionated samples represent the study material for the thesis. Using 63,371 unique diatom metabarcodes, this study presents an in-depth evaluation of global diatom distribution and diversity. The analyses study draw a number of revelations related to diatom biogeography, e.g. a new estimate of the total number of planktonic diatom species, a considerable unknown diversity, exceptionally high diversity in the open ocean, complex diversity patterns across oceanic provinces. The thesis then looks into the factors determining the beta-diversity patterns. The results suggest that diatoms represent biogeographically structured ecological communities regulated by both environmental heterogeneity and spatial processes. Nonetheless, the majority of the total variation in community composition remained unexplained by either the examined measured environmental factors or spatial distances, which warrants future analyses focusing on biological interactions, historical events, and other factors that are not considered. The thesis further outlines an approach to characterize significantly associated clusters of co-occurring ribotypes. Finally, a preliminary study of size-fractionated protistan communities reveals that the tail (of their rank-abundance distributions) appears to follow a power-law behavior in almost all protistan communities. This observation may indicate a potential universal mechanism which can explain the organization of marine planktonic communities. In general, this work has presented a global comprehensive perspective on diatom distribution and diversity in the world’s oceans. The thesis offers an overall framework for metabarcoding-based global diversity assessments which in turn can be employed to study distribution and diversity of other taxonomic lineages. Consequently, this work provides a reference point to explore how microbial communities will respond/change in response to environmental conditions.
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Comparaison de novo de données de séquençage issues de très grands échantillons métagénomiques : application sur le projet Tara Oceans / De novo comparision of huge metagenomic experiments coming from NGS technologies : application on Tara Oceans projectMaillet, Nicolas 19 December 2013 (has links)
La métagénomique vise à étudier le contenu génétique et génomique d'un échantillon provenant d'un environnement naturel. Cette discipline récente s'attache à étudier les génomes de différents organismes provenant d'un même milieu. La métagénomique pose de nouvelles questions, tant d'un point de vue biologique qu'informatique. Les masses de données générées par les études métagénomiques et la complexité des milieux étudiés, nécessitent de développer de nouvelles structures de données et de nouveaux algorithmes dédiés. Parmi les différentes approches existantes en métagénomique, la métagénomique comparative consiste à comparer plusieurs métagénomes afin d'en connaître les divers degrés de similarité. Lorsque cette comparaison se base uniquement sur le contenu brut des échantillons, sans faire appel à des connaissances externes, on parle de métagénomique comparative de novo. L'objectif des travaux que nous proposons est de développer une méthode permettant d'extraire les séquences similaires de deux jeux de données métagénomiques, où chaque jeu peut être composé de centaines de millions de courtes séquences. La comparaison proposée consiste à identifier les séquences d'un premier jeu similaires à au moins une séquence d'un second jeu. Afin d'être rapide et économe en mémoire, l'implémentation de notre méthode a nécessité la conception d'une nouvelle structure d'indexation, basée sur le filtre de bloom. Le logiciel final, nommé Compareads, a une consommation mémoire faible (de l'ordre de quelques go) et peut calculer l'intersection de deux échantillons de 100 millions de séquences chacun en une dizaine d'heures. Notre méthode est une heuristique qui génère un faible taux de faux positifs. Le logiciel Compareads est dédié à l'analyse de grands jeux de données métagénomiques. À l'heure actuelle, il est le seul outil capable de comparer de tels jeux. Compareads a été appliqué sur plusieurs projets métagénomiques. Notre outil produit des résultats robustes, biologiquement exploitables et en accord avec diverses méthodes fondamentalement différentes. Il est actuellement utilisé de manière intensive sur les échantillons provenant de l'expédition tara oceans. Sur ce projet, notre méthode à permis de mettre en évidence que les grands systèmes océaniques influent sur la répartition globale des micro-organismes marins. / Metagenomics studies overall genomic information of multiple organisms coming from the same biotope. The information is generally provided by next generation sequencing technologies (NGS). Typical data are samples of short reads (i.e. reads of few hundred base pairs). To study such metagenomics information, we developed an original method for extracting similarities between two samples of reads. More precisely, this approach locates the set of common reads present in two samples. In order to fit with current memory capacities and to be time efficient, we used a modified Bloom filter data structure. Finding the common reads between multiple samples and crossing this information with the location of samples leads to visualize some biological processes like ubiquitous species or effect of water stream caring some species. Finally, the tool can also be used as a filter on metagenomics datas to remove for example only one specie. Our software, Compareads, is actually used on the Tara Oceans project where it shows that global dynamic of oceans seems to play a part on the dispersion of marine microorganisms.
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Estudio de la diversidad genética de individuos de poblaciones silvestres de Caesalpinia spinosa (Molina) Kuntze "Tara" mediante análisis de patrones electroforéticos de proteínas seminalesLinares Gonzáles, José Ricardo January 2014 (has links)
Se realizó el estudio electroforético de proteínas seminales totales de 18 individuos de poblaciones silvestres de Caesalpinia spinosa (Molina) Kuntze, procedentes de Tarma, Ayacucho y Cajamarca, en geles de poliacrilamida con Sodio Dodecil Sulfato SDS-PAGE. Las proteínas fueron extraídas a partir de la harina de la semilla mediante el uso de un buffer de extracción que contenía 0.5M Tris-HCl (pH 8.0), 0.2% SDS, 5M úrea y 1% 2-mercaptoetanol, glicerol al 10 % (v/v). La cantidad de proteínas se determinó mediante el método de Biuret. Asimismo mediante el análisis densitométrico se logró identificar 22 bandas proteicas las cuales mostraron diferencias en sus movilidades. De esta manera se obtuvieron modelos electroforéticos diferentes para algunos de los individuos y mediante un análisis de conglomerados (método UPGMA) se obtuvo un dendrograma que mostró la distinción entre individuos en dicho carácter, permitiendo expresar las diferencias entre ellos. Se identificó que existen bandas únicas las cuales solamente se encuentran en individuos de Cajamarca (banda de 94-91 kDa y de 49-46 kDa) y bandas que son excluyentes pues solamente se encuentran en individuos de Tarma y Ayacucho (64-61 kDa). Por lo que se concluye se concluye que la cantidad de proteínas no guarda relación con la zona de procedencia, que los individuos analizados comparten un mismo acervo genético y que el patrón electroforético de la semillas de “tara” analizadas permite identificar su procedencia geográfica.
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Efecto antibacteriano de Caesalpinia spinosa (tara) sobre flora salival mixtaHuarino Acho, Mariella January 2011 (has links)
La tara es una planta oriunda del Perú, la cual es más usada en la industria peletera o en la producción de goma de tara. Esta planta tiene amplia utilización empírica, por sus propiedades curativas, en: infecciones bronquiales, como antiinflamatorio, casos de sinusitis; infecciones vaginales y micóticas, heridas crónicas y piezas dentales con caries dental. Tiene escasos estudios científicos que lo comprueben. Por lo tanto el uso empírico de la tara en el tratamiento de infecciones bronquiales nos permite deducir que esta planta tiene efecto antibacteriano sobre las bacterias que lo causan.
Teniendo en cuenta que nuestra población necesita alternativas de costo reducido y alto beneficio para el tratamiento de lesiones que lo haría accesible a las clases más populares. Se ha realizado una investigación dirigida a comprobar el efecto antibacteriano de la tara.
En concordancia con lo mencionado anteriormente, este estudio tiene como objetivo determinar la existencia del efecto antibacteriano del extracto alcohólico de la Caesalpinia spinosa “Tara” sobre flora salival mixta.
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Utilización de la Caesalpinia spinosa, para la optimización del proceso de curtición de pieles de cabra: planta pilotoHidalgo Almeida, Luis Eduardo January 2017 (has links)
Publicación a texto completo no autorizada por el autor / Desarrolla un sistema de utilización de la Caesalpinia spinosa (Tara) como insumo ecológico en el proceso de curtición de pieles de cabra, que reemplace al cromo y mejore las condiciones de esta industria en el Ecuador. Define una propuesta de factibilidad económica y productiva de una planta piloto de fabricación de pieles de cabra curtidas con Caesalpinia spinosa, para obtener un producto final amigable con el ambiente, de excelente calidad, y que sea competitivo frente a los cueros producidos con cromo en forma contaminante. / Tesis
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Obtención de ácido gálico a partir de taninos, presentes en el polvo de vainas de tara (Caesalpinea spinosa (Molina) Kuntze) usando hongos nativos mediante proceso de fermentaciónOrtega Asencios, Susan Lourdes January 2015 (has links)
Publicación a texto completo no autorizada por el autor / Obtiene el ácido gálico mediante el aislamiento de hongos nativos a partir de las vainas de tara procedente de los departamentos de Ayacucho, Huaraz y Lima, durante 7 días de evaluación mediante el Método de Cámara Húmeda. Consiguiendo, un total de 34 cepas fúngicas aisladas de las vainas de tara, de las cuales el 76.47% lo representa las cepas del género Aspergillus y el 23.53% del género Penicillium. Del total de cepas fúngicas aisladas se seleccionaron aquellas que presentaron mayor capacidad en el uso de ácido tánico, siendo para ello previamente sembradas en Agar Czapeks Dox suplementado con 1% de ácido tánico a nivel in vitro, evaluando a lo largo de 5 días el radio de crecimiento. Siendo así seleccionadas las cepas de Aspergillus aisladas de las vainas de tara procedentes del departamento de Huaraz identificadas como: HRTAS-02 y HRTAS-09 con radio de crecimiento de 3.5 cm. y 3.25 cm. respectivamente, al primer día de evaluación. Así mismo, se realizó la caracterización física y química del polvo de vaina de tara procedente del departamento de Ayacucho debido a que presenta el mayor contenido de taninos, lo cual se demuestra mediante el método titrimétrico obteniendo el 65.68% de taninos. Los resultados obtenidos se compararon con el método de hidrolisis química ácida en la cual se obtuvo una concentración de 73.01 mg/l de ácido gálico. Siendo el 73.34% la conversión de los taninos presentes en el polvo de vaina de tara a ácido gálico obtenido a partir del método de fermentación enzimática. / Tesis
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Estudo estrutural, termodinâmico e reológico das gomas gelana e tara em meios aquosos: efeito da concentração, pH e força iônica / Study of structure, thermodynamic and rheology of gellan gum and tara in aqueous solutions : effect of concentration, pH and ionic strengthNeves, Erick Ornellas 25 February 2015 (has links)
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Previous issue date: 2015-02-25 / Os hidrocoloides são empregados há muito tempo pelas indústrias, sendo em alguns casos os principais promotores das características reológicas do material. A avaliação das fontes de variação presentes em alimentos que possam causar impacto estrutural (químico e espacial) permite um controle adequado do desempenho do hidrocoloide na modificação do perfil reológico do sistema. Neste trabalho foram estudados dois hidrocoloides, goma gelana e goma tara, sendo caracterizado o perfil reológico dos sistemas onde estes eram empregados e feita a caracterização dos hidrocoloides por técnicas físico- químicas. Foram avaliados o perfil de sistemas com a adição de cloreto de sódio de O a 150 mmol/L e de pH entre 3,5 a 5,5 e a interação entre estes fatores e o hidrocoloide. Foram avaliados o perfil reológico dos sistemas com relação ao comportamento ao escoamento, tixotropia e viscoelasticidade, variando também a concentração de hidrocoloide no meio. Já o volume específico parcial e o raio hidrodinâmico foram avaliados somente com relação ao pH e força iônica para os diferentes hidrocoloides. As técnicas de viscosidade intrínseca e calorimetria foram utilizadas na caracterização da goma gelana no meio. Os resultados demonstraram para a goma gelana a importância da interação do cloreto de sódio com esta goma, alem da importância dos fatores isoladamente na construção do perfil reológico do meio. Para as condições de pH 4,5 e 5,5 foi observada pouca diferença com relação aos resultados reológicos, porém para pH 3,5 verificou-se grande modificação de perfil frente aos outros. Estruturalmente o pH 3,5 tende a protonar a molécula, ocasionando maior aproximação das estruturas, porém a presença do cloreto de sódio permite até determinada concentração uma maior interação do polímero com a água. Após a concentração crítica, esta interação diminuiu e uma maior interação polímero-polímero foi formada, aumentado mais intensamente o módulo elástico do que o viscoso. Já os sistemas com goma tara apresentaram um perfil reológico muito dependente da concentração do hidrocoloide, com pouca dependência entre os fatores de pH e cloreto de sódio. O pH tem uma importância associada à temperatura, onde, nas emperaturas utilizadas, a preparação ocasionou uma despolimerização do hidrocoloide. Esta despolimerização foi associada a uma interação do pH com a concentração de hidrocoloide, onde uma maior concentração de hidrocoloide acarretou em maior grau de despolimerização. O aumento da concentração de cloreto de sódio tendeu a afetar negativamente o módulo elástico, mas de forma modesta. Estruturalmente o volume específico parcial foi afetado pelo cloreto de sódio, mas não pelo pH. A diminuição do volume específico parcial esteve associada a uma diminuição do covolume do hidrocoloide, mas de forma a não alterar o raio hidrodinâmico. Provavelmente esta alteração do volume esteja associada a uma maior interação intramolecular. Assim podemos observar que a importância dos fatores pH e cloreto de sódio e dependente da estrutura observada, sendo que o seu grau de importância esteve associado não só ao fator isolado, mas à sua interação, sobretudo, com o hidrocoloide. / Hydrocolloids have been applied by factories for a long time and in some cases they are the main substances that modifies rheological characteristics of a material. The evaluation of variation sources contained in food that may cause structural impact (chemical or spatial), allow a suitable control of the hydrocolloid performance in modifying the system rheological profile. In this present work, two different hydrocolloids were studied, gellan and tara gum, and the systems which had these gums applied were characterized according to their rheological properties. Hydrocolloids were characterized by physic- chemical techniques. System profile was evaluated according to the addition of sodium chloride (0 to 150 mg/L), to the adjust of pH (3.5 to 5.5) and to the interaction between these factors and the hydrocolloid. Besides these variables, concentration of hydrocolloid was also studied in the rheological behavior. The evaluation of the systems was performed analyzing their flow behavior, tixotropy and viscoelasticity. However, the partial specific volume and hydrodynamic radius were evaluated only in relation to the pH and ionic strength for both hydrocolloids. Techniques of intrinsic viscosity and calorimetry were applied to characterize gellan gum in the medium. Results pointed out an important interaction between gellan gum and sodium chloride, besides the importance of the isolated factors in the building of medium rheological profile. Rheological results were slightly different in pH 4.5 and 5.5. However, for pH 3.5, huge difference in the profile was observed. Molecules tend to be protonated in pH 3.5, leading to the approximation of the structures. When sodium chloride is present, it allowed until a certain concentration, a higher interaction between the polymer and water. Beyond the critical concentration, this interaction decreased, and the interaction polymer-polymer was formed more intensively, what resulted in the increase of the G' in relation to the G”. When tara gum was used, the systems showed a rheological profile very dependent on the hydrocolloid concentration, presenting low dependence with the factors pH and sodium chloride. The pH has an importance associated with temperature. Temperatures used in these experiments caused a hydrocolloid depolymerization, which was associated to an interaction pH and hydrocolloid concentration, where high hydrocolloid concentration Ieaded high depolymerization. G” was slightly and negatively affected by increasing sodium chloride concentration. Partial specific volume was affected by sodium chloride, but it was not affected by the pH. The decrease of partial specific volume was associated to the decrease of the hydrocolloid co-volume, however it occurred with no effect in the hydrodynamic radius. This variation in the volume is likely associated to a stronger intramolecular interaction. Therefore, it is possible to observe that the importance of the factors pH and sodium chloride is structurally dependent and the degree of importance is associated not only to an isolated factor, but it is also associated to the interaction of these variables with the hydrocolloid.
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Efeito da adição de goma tara e carragena em iogurte firme desnatado / Effect of tara gum and carrageenan addition in non fat set yogurtHatanaka, Camila Lie 12 August 2018 (has links)
Orientador: Mirna Lucia Gigante / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-12T19:47:23Z (GMT). No. of bitstreams: 1
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Previous issue date: 2009 / Resumo: Atualmente a adição de hidrocolóides é um recurso utilizado em produtos lácteos para modificar a textura ou evitar defeitos como a sinérese. Hidrocolóides são utilizados como agentes espessantes, gelificantes e estabilizantes, e podem apresentar características sinérgicas quando utilizados em conjunto. O objetivo deste trabalho foi avaliar o efeito da adição de goma tara e carragena sobre a sinérese do iogurte firme desnatado. Os iogurtes foram fabricados com leite desnatado reconstituído adicionado de goma tara e carragena, em concentrações variando de 0 a 0,0585%, em combinações previstas pela metodologia de superfície de resposta. Após aproximadamente 48 horas de armazenamento refrigerado, determinou-se a composição dos iogurtes e a sinérese, que foi avaliada de três formas distintas: sinérese espontânea, por drenagem e por centrifugação. A goma tara afetou significativamente a sinérese do produto, que aumentou em concentrações superiores a 0,0293%, independentemente da sua forma de avaliação. A sinérese não foi significativamente afetada pela adição de carragena e nem pela interação entre os polissacarídeos. As concentrações escolhidas para fabricação e avaliação dos iogurtes durante o armazenamento refrigerado (29 dias) foram iogurte controle (sem adição de polissacarídeos), iogurte com 0,02% de goma tara e iogurte com 0,02% de tara + 0,02% de carragena. Após aproximadamente 24 horas os iogurtes foram avaliados quanto à composição centesimal. Durante o armazenamento refrigerado, após 1, 8, 15, 22 e 29 dias de fabricação os produtos foram avaliados quanto à sinérese espontânea, firmeza, e pH para acompanhamento da pós-acidificação. A sinérese espontânea foi significativamente afetada pelos tratamentos, sendo que a menor liberação de soro foi observada para o iogurte fabricado com goma tara e carragena, enquanto que o iogurte que continha apenas goma tara apresentou maior sinérese. A firmeza foi significativamente afetada pelos tratamentos. O iogurte fabricado com goma tara e carragena apresentou menor firmeza quando comparado ao iogurte controle, sendo que ambos não diferiram significativamente do iogurte fabricado com goma tara. Durante o tempo de armazenamento refrigerado a firmeza dos iogurtes aumentou significativamente. Os tratamentos afetaram significativamente a pós-acidificação dos iogurtes, sendo que o iogurte controle apresentou menor pH quando comparado ao iogurte fabricado com adição de goma tara e carragena. O pH de todos os produtos diminuiu significativamente nos primeiros 8 dias de armazenamento refrigerado, mantendo-se estável após esse período / Abstract: Nowadays, the hydrocolloids addition is an applied mean to modify the texture or to avoid defects, such as syneresis, in dairy products. Hydrocolloids can be utilized as thickening, gelling and stabilizing agents, and can show synergistic features when applied along each other. The objective of this research was to evaluate the effect of addition of tara gum and carrageenan on the syneresis of non-fat set yogurt. Non-fat reconstituted milk added with carrageenan and tara gum in concentrations from 0 to 0.0585%, at combinations given by response surface methodology, was used. Composition and syneresis (spontaneous, by drainage, and by centrifugation) evaluations were done after 48 hours of cold storage. Tara gum significantly affected the syneresis, increasing it in concentrations higher than 0.0293%, independent of the type of syneresis evaluation. The effects of carrageenan and polysaccharides¿ interaction on the syneresis were not significative. The concentrations evaluated during 29 days were control yogurt (no polysaccharide addition), yogurt with 0.02% of tara gum and yogurt with 0.02% of tara gum and 0.02% of carrageenan. Composition was evaluated approximately after 24 hours. The pH (for post-acidification evaluation), spontaneous syneresis and firmness were evaluated during the cold storage at 1, 8, 15, 22 and 29 days after manufacture of yogurts. Natural syneresis was affected by the treatments and yogurt with tara gum and carrageenan showed the lowest whey-off, while the yogurt containing only tara gum showed the highest syneresis. Firmness was significantly affected by treatments. The lowest firmness was observed in yogurt containing carrageenan and tara gum, when compared to control yogurt, but both yogurts didn't differed from yogurt containing only tara gum. Yogurt firmness increased during cold storage. Regarding the post-acidification, the treatments significantly affected the pH and the control yogurt showed the lowest pH, if compared to yogurt manufactured with tara gum and carrageenan. The pH of all yogurts significantly decreased at the first eight days of cold storage, stabilizing during cold storage / Mestrado / Mestre em Tecnologia de Alimentos
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TARA : - En kvalitativ studie om läkarstudenters upplevelser av TARABurström, Anna January 2020 (has links)
Depression är vanligt förekommande världen över och läkarstudenter är en utsatt grupp. Under läkarprogrammet ökar dessutom den psykiska ohälsan bland studenterna. Förmågan till psykologisk flexibilitet, innefattande defusion, acceptans, jag-som-kontext, flexibel uppmärksamhet i nuet, värden och ändamålsenligt handlande, har visat sig ha samband med ohälsa. Training for Awareness, Resilience and Action (TARA) har skapats i USA som metod för att i grupp behandla depression hos tonåringar. Under 2018 erbjöds TARA till en grupp läkarstudenter i Umeå och denna kvalitativa studie innefattade semistrukturerade intervjuer två år efter avslutad behandling. Deltagarna var fem av dessa studenter och intervjuerna fokuserade på deras upplevelser av TARA samt vilka metoder de fortsatt att använda. Åldern på deltagarna var 21-32 år vid intervjutillfället. En tematisk analys användes för att analysera materialet från intervjuerna. Resultatet visade att deltagarna upplevde att de fick flera olika verktyg att använda sig av för att hantera sin psykiska ohälsa. Främst var andningsövningar och att uppmärksamma det som hände inom dem som beskrevs som det viktigaste. Deltagarnas beskrivningar av deras erfarenheter visar att de övat upp sin förmåga till defusion, acceptans, flexibel uppmärksamhet i nuet, värden och ändamålsenligt handlande under TARA. Beskrivningar av jag-som-kontext gick inte att hitta i materialet. Studiens utformning, kvalitativa intervjuer, och urvalet av deltagare har minskat möjligheten till generalisering. Dock kan resultatet förstås som att TARA kan hjälpa till att öka upplevelsen av psykologisk flexibilitet, vilket i förlängningen kan minska symtomen på depression. / Depression is common worldwide and medical students are a vulnerable group and during the medical education mental illness increases. The ability for psychological flexibility, including diffusion, acceptance, Self-as-context, flexible contact with the present, values and appropriate action, has been shown to be associated with ill health. Training for Awareness, Resilience and Action (TARA) has been created in the United States as a method of treating depression in group in adolescents. In 2018, TARA was offered to a group of medical students in Umeå and this qualitative study included semi-structured interviews with five of these students about their experiences of TARA and what methods they are using. The interviews were conducted two years after their participation in TARA. The participants attended the second and forth semester of their education when TARA occurred. The age of the participants was 21-32 years at the time of the interview. A thematic analysis was used to analyze the material from the interviews. The results showed that the participants felt that they were given several different tools to use to manage their mental illness. Mainly breathing exercises and paying attention to what was happening within them was described as the most important. The participants' descriptions of their experiences show that they practiced their ability for defusion, acceptance, flexible contact with the present, values and appropriate action during TARA. Descriptions of Self-as-context couldn’t be found in the material. The design of the study, qualitative interviews, and the selection of participants have reduced the possibility of generalization. However, the result can be understood as that TARA can help to increase the experience of psychological flexibility, which in the long run can reduce the symptoms of depression.
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Cybersecurity: Digital Twins in Automotive Industry : The Road Ahead – An Exploratory StudyUpara, Rossarin January 2023 (has links)
The digital twin is a concept that has attracted the attention of both industry and academia in the last decade with the advent of Industry 4.0 and the adoption of future technologies. Previous research has shown that the automotive industry is facing significant challenges as demand for advanced, connected systems increases, and with it, cybersecurity risks. As the automotive industry has evolved, this concept has become prevalent in many areas and is now applied to products and systems throughout their lifecycle, which also means that the digital twin plays a key role in many development processes. Therefore, it is important to investigate what the cybersecurity stands in terms of cybersecurity. This study takes an exploratory approach that primarily aims to investigate and gain a broader perspective on a relatively unexplored topic, namely cybersecurity for digital twins in the automotive industry. The application of digital twins in the automotive industry was explored to determine what security challenges exist and whether these challenges can be solved using existing security paradigms. Industrial use cases were developed to illustrate the digital twins that exist in the automotive industry. In addition, at an overall level, a threat analysis and risk assessment (TARA) is conducted, again using STRIDE, one of the most commonly used threat models, to identify potential risks and attacks that exist and how they might be addressed in each case. Semi-structured interviews were also conducted with four experts working with digital twins and future innovations in the automotive industry to gain insight into how the experts view the digital twin in the context of cybersecurity, risks and threats of digital information. The results of the TARA analysis and the interviews showed that there are many different risks for digital twins that may vary between digital twins, and that there is a common denominator for all of them that can be defined as the biggest challenge for the digital twin, which is data and its related risks. Thus, it can be said that the security paradigms for solving the digital twin are based on the threats and risks of the individual digital twin. / Digital tvilling är ett koncept som har uppmärksammats av både industrin och akademin under det senaste decenniet i och med uppkomsten av Industri 4.0 och introduktionen på framtidens tekniker. Tidigare forskning visar på att bilindustrin står inför stora utmaningar där efterfrågan på avancerade uppkopplade system efterfrågas, i samband med detta har även cybersäkerhetsriskerna ökat. Detta koncept har även med bilindustrins utveckling adopterats brett inom många områden och tillämpas idag på produkter och system under hela dess livscykel, vilket även innebär att den digitala tvillingen har en nyckelroll i många utvecklingsprocesser. Därmed är det relevant att undersöka hur den digitala tvillingen står sig gällande cybersäkerhet. Denna studie har en explorativ ansats som primärt syftar till att undersöka ett relativt outforskat ämne och få ett bredare perspektiv, nämligen cybersäkerhet för digitala tvillingar inom bilindustrin. Tillämpningen av den digitala tvillingen inom bilindustrin undersöks för att ta reda på vilka säkerhetsutmaningar som finns samt identifiera om dessa utmaningar kan lösas med befintliga säkerhetsparadigm. Industriella användningsfall tas fram för att exemplifiera på digitala tvillingar som finns inom bilindustrin, vidare utförs hotanalys och riskbedömning (TARA) på en övergripande nivå där även STRIDE, ett av de mest tillämpade hotmodeller, används för att kartlägga möjliga risker och attacker som finns hur de möjligtvis kan åtgärdas för det enskilda fallet. Semi-strukturerade intervjuer utfördes med fyra experter som arbetar med digital tvilling och framtida innovationer inom bilindustrin för att få insikt på hur dessa experter ser på den digitala tvillingen i kontexten cybersäkerhet, risker och hot av digital information. Med resultaten från TARA analysen samt intervjuerna gick det att få fram att det finns många olika risker för digitala tvillingar som kan variera mellan de enskilda digitala tvillingarna samt att det finns en gemensam nämnare för samtliga som går att definiera som den största utmaningen för den digitala tvillingen vilket är data och dess relaterade risker. Med detta kan man säga att säkerhetsparadigmerna för att lösa den digitala tvillingen baseras på den enskilda digitala tvillingens hot och risker.
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