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Submitted to Magnetic Resonance in Medicine; Purpose: To evaluate the benefits of SPARKLING, a stochastic k-space sampling approach over the deterministic sampling scheme TPI (Twisted Projection Imaging) in the context of accelerated cerebral $^{23}$Na MRI and assessing its impact on tissue sodium concentration (TSC) estimation.Methods: Guided by simulation results, in vitro and in vitro UTE $^{23}$Na MRI datasets were acquired at a 4 mm isotropic resolution from healthy volunteers using both TPI or SPARKLING trajectories with different acceleration factors (AF) on a 7T MR scanner equipped with a 32 channels head coil. Following reconstruction using NUFFT or Proximal Optimized Gradient Method (POGM) algorithms with or without regularization, respectively, the resulting sodium images were compared in terms of effective resolution (FWHM of the PSF), SNR and overall quality. with an in vitro assement of the accuracy of the TSC was performed via external referencing using a 4-point calibration approach. Results: In vivo cerebral sodium images acquired using SPARKLING with an acceleration factor of 32 (TA= 5 min 38 s) are similar to those obtained using TPI at AF=8 (TA= 22 min 34 s) with minimal impact on the accuracy of our TSC quantification. Conclusion: In conditions compatible with clinical examination, undersampled SPARKLING $^{23}$Na MRI can outperform the conventional TPI k-space sampling scheme allowing for shorter acquisition times.

International audience; Patient-induced inhomogeneities in the magnetic field cause distortions and blurring during acquisitions with long readouts such as in susceptibility-weighted imaging (SWI). Most correction methods require collecting an additional ∆B 0 field map to remove these artifacts. The static ∆B0 field map can be approximated with an acceptable error directly from a single echo acquisition in SWI. The main component of the observed phase is linearly related to ∆B0 and the echo time TE , and the relative impact of non-∆B0 terms becomes insignificant with TE > 20ms at 3T for a well-tuned system. The main step is to combine and unfold the multi-channel phase maps wrapped many times, and several competing algorithms are compared for this purpose. Four in vivo brain data sets collected using the recently proposed 3D SPARKLING readouts are used to assess the proposed method. The estimated 3D field maps generated with a 0.6 mm isotropic spatial resolution provide overall similar off-resonance corrections compared to reference corrections based on an external ∆B0 acquisitions, and even improved for two out of four individuals. Although a small estimation error is expected, no aftermath was observed in the proposed corrections, while degradations were observed in the references. A static ∆B0 field map estimation method was proposed to take advantage of acquisitions with long echo times, and outperformed the reference technique based on an external field map. The difference can be attributed to an inherent robustness to mismatches between volumes and external ∆B0 maps, and diverse other sources investigated.

International audience; Patient-induced inhomogeneities in the magnetic field cause distortions and blurring during acquisitions with long readouts such as in susceptibility-weighted imaging (SWI). Most correction methods require collecting an additional ∆B 0 field map to remove these artifacts. The static ∆B0 field map can be approximated with an acceptable error directly from a single echo acquisition in SWI. The main component of the observed phase is linearly related to ∆B0 and the echo time TE , and the relative impact of non-∆B0 terms becomes insignificant with TE > 20ms at 3T for a well-tuned system. The main step is to combine and unfold the multi-channel phase maps wrapped many times, and several competing algorithms are compared for this purpose. Four in vivo brain data sets collected using the recently proposed 3D SPARKLING readouts are used to assess the proposed method. The estimated 3D field maps generated with a 0.6 mm isotropic spatial resolution provide overall similar off-resonance corrections compared to reference corrections based on an external ∆B0 acquisitions, and even improved for two out of four individuals. Although a small estimation error is expected, no aftermath was observed in the proposed corrections, while degradations were observed in the references. A static ∆B0 field map estimation method was proposed to take advantage of acquisitions with long echo times, and outperformed the reference technique based on an external field map. The difference can be attributed to an inherent robustness to mismatches between volumes and external ∆B0 maps, and diverse other sources investigated.

Filamentous fungi are rarely reported as responsible for spoiling wine. Cork taint was detected in sparkling wine, therefore, we investigated fungal contamination as a possible cause of organoleptic alteration. Spoiled wine was filtered and membranes were plated onto potato dextrose agar (PDA). The cork stoppers used for sealing bottles were cut and also plated onto PDA. Fungal strains were phenotypically characterized and molecularly identified by sequencing of a fragment of the 28S nrRNA gene (LSU) and (occasionally) by other additional molecular markers. Twenty-seven strains were isolated and sixteen species were identified, all of them belonging to the phylum Ascomycota. The fungi isolated from wine were three species of Aspergillus section Nidulantes, a species of Penicillium section Exicaulis and Beauveria bassiana. Candida patagonica was isolated from both sort of samples, and the fungi isolated from cork stoppers were Altenaria alternata and Cladosporium cladosporioides. Surprisingly, most of the taxa recovered from the cork stoppers and/or wine were new to the science: a new genus (Dactylodendron) and seven new species belonging to the genera Cladophialophora, Dactylodendron, Kirschsteiniothelia, Rasamsonia, and Talaromyces. Future studies could let us know if these fungi would be able to produce compounds responsible for cork taint.

Submitted by DSpace Unilasalle (dspace@unilasalle.edu.br) on 2019-08-22T18:24:44Z No. of bitstreams: 1 pesfcampos.pdf: 2470934 bytes, checksum: 5049510af2250b32a08e68e63b8ee4a6 (MD5) Made available in DSpace on 2019-08-22T18:24:44Z (GMT). No. of bitstreams: 1 pesfcampos.pdf: 2470934 bytes, checksum: 5049510af2250b32a08e68e63b8ee4a6 (MD5) Previous issue date: 2019 Percebe-se que o conhecimento é um recurso fundamental para o crescimento dos negócios. Aristóteles preconizava que o poder vem do conhecimento. Quando pensamos no segmento da vitivinicultura brasileira levantamos uma hipótese de como foram e serão transmitidos os conhecimentos adquiridos e repassados para as gerações. Neste cenário, a articulação entre memória de família e conhecimento intraorganizacional é o tema deste estudo. Assim, esta dissertação tem por objetivo analisar, em relação às práticas de compartilhamento do conhecimento intraorganizacional, a partir do modelo SECI, as contribuições para a Adega Chesini no período compreendido de seu início a 2018. A coleta de dados utilizou como principais fontes a pesquisa documental, observação direta e a entrevista semiestruturada. Os resultados deste estudo revelam, de forma especifica, que: (a) a socialização do conhecimento se dá a partir de reuniões (formais, informais), participações em associações ligadas ao negócio e no aprendizado do tipo “mestre aprendiz”. (b) a externalização dos conhecimentos ocorre por intermédio do desenvolvimento da participação em eventos externos e premiações; (c) a combinação do conhecimento se dá a partir da troca de e-mails e utilização de WhatsApp e ao acesso do site da Adega Chesini; (d) na internalização os métodos facilitadores à internalização do conhecimento são, acesso a materiais de leitura, site da Adega e criação do espaço cultural; (e) observou-se que as práticas de compartilhamento do conhecimento intraorganizacional contribuem para a aprendizagem informal, criação de novos conhecimentos tácitos para a criação de novos produtos desenvolvidos na Adega Chesini e para a implementação de melhorias e memória na Adega. It is perceived that knowledge is a fundamental resource for business growth. Aristotle advocated that power comes from knowledge. When we think of the segment of Brazilian winemaking, we hypothesize how the knowledge acquired and passed on to generations has been and will be transmitted. In this scenario, the articulation between family memory and knowledge within organization is the theme of this study. The aim of this dissertation is to analyze the contributions to the Adega Chesini in the period from its inception to 2018, in relation to the practices of knowledge sharing within the organization, from the SECI model. Data collection used as main sources the documentary research and the semistructured interview. The results of this study reveal, in a specific way, that: (a) the socialization of knowledge occurs from meetings (formal, informal), participations in associations linked to the business and learning "master and apprentice" type. (b) the externalization of knowledge occurs through the development of participation in external events and awards; (c) the combination of knowledge comes from the exchange of emails and use of whataspp and access to the Adega Chesini website; (d) in the internalization the methods facilitating the internalization of knowledge are, access to reading materials. Winery site and creation of cultural space; (e) it was verified that the practices of knowledge sharing within the organization contribute to informal learning, creation of new tacit knowledge, to the creation of new products developed at the Adega Chesini and to the implementation of improvements and memory in the Winery

Magnetic resonance imaging (MRI) is one of the most powerful and safest imaging modalities for examining the human body. High-resolution MRI is expected to aid in the understanding and diagnosis of many neurodegenerative pathologies involving submillimetric lesions or morphological alterations, such as Alzheimer’s disease and multiple sclerosis. Although high-magnetic-field systems can deliver a sufficient signal-to-noise ratio (SNR) to increase spatial resolution, long scan times and motion sensitivity continue hindering the utilization of high resolution MRI. Despite the development of corrections for bulk and physiological motion, lengthy acquisition times remain a major obstacle to high-resolution acquisition, especially in clinical applications.In the last decade, the newly developed theory of compressed sensing (CS) offered a promising solution for reducing the MRI scan time. After having explained the theory of compressed sensing, this PhD project proposes an empirical and quantitative analysis of the maximum undersampling factor achievable with CS for T ₂ *-weighted imaging.Furthermore, the application of CS to MRI commonly relies on simple sampling patterns such as straight lines, spirals or slight variations of these elementary shapes, which do not take full advantage of the degrees of freedom offered by the hardware and cannot be easily adapted to fit an arbitrary sampling distribution. In this PhD thesis, I have introduced a method called SPARKLING, that may overcome these limitations by taking a radically new approach to the design of k-space sampling. The acronym SPARKLING stands for Spreading Projection Algorithm for Rapid K-space sampLING. It is a versatile method inspired from stippling techniques that automatically generates optimized non-Cartesian sampling patterns compatible with MR hardware constraints on maximum gradient amplitude and slew rate. These sampling curves are designed to comply with key criteria for optimal sampling: a controlled distribution of samples and a locally uniform k-space coverage. Before engaging into experiments, we verified that our gradient system was capable of executing the complex gradient waveforms. We implemented a local phase measurement method and we observed a very good adequacy between prescribed and measured k-space trajectories.Finally, combining sampling efficiency with compressed sensing and parallel imaging, the SPARKLING sampling patterns allowed up to 20-fold reductions in MR scan time, compared to fully-sampled Cartesian acquisitions, for T ₂ *-weighted imaging without deterioration of image quality, as demonstrated by our experimental results at 7 Tesla on in vivo human brains. In comparison to existing non-Cartesian sampling strategies (spiral and radial), the proposed technique also yielded superior image quality. Finally, the proposed approach was also extended to 3D imaging and applied at 3 Tesla for which preliminary results on ex vivo phantoms at 0.8 mm isotropic resolution suggest the possibility to reach very high acceleration factors up to 60 for T ₂ *-weighting and susceptibility-weighted imaging.; L'imagerie par résonance magnétique (IRM) est l'une des modalités d'imagerie les plus puissantes et les plus sures pour examiner le corps humain. L'IRM de haute résolution devrait aider à la compréhension et le diagnostic de nombreuses pathologies impliquant des lésions submillimétriques ou des maladies telles que la maladie d'Alzheimer et la sclérose en plaque. Bien que les systèmes à haut champ magnétique soient capables de fournir un rapport signal-sur-bruit permettant d'augmenter la résolution spatiale, le long temps d'acquisition et la sensibilité au mouvement continuent d'entraver l'utilisation de l'IRM de haute résolution. Malgré le développement de méthodes de correction du mouvement et du bruit physiologique, le long temps d'acquisition reste un obstacle majeur à l'IRM de haute résolution, en particulier dans les applications cliniques.Au cours de la dernière décennie, la nouvelle théorie du compressed sensing (CS) a proposé une solution prometteuse pour réduire le temps d'examen en IRM. Après avoir expliqué la théorie du compressed sensing, ce projet de thèse propose une étude empirique et quantitative du facteur de sous-échantillonnage maximum réalisable grâce au CS pour l'imagerie pondérée en T ₂ *.En outre, l'application de CS en IRM repose généralement sur l'utilisation de courbes d'échantillonnage simples telles que les lignes droites, spirales ou des légères variations de ces formes élémentaires qui ne tirent pas pleinement parti des degrés de liberté offerts par le hardware et ne peuvent être facilement adaptées à une distribution d'échantillonnage arbitraire. Dans cette thèse, j'ai introduit une méthode appelée SPARKLING, qui permet de surmonter ces limitations en adoptant une approche radicalement nouvelle de la conception de l'échantillonnage de l'espace-k. L'acronyme SPARKLING signifie Spreading Projection Algorithm for Rapid K-space sampLING. C'est une méthode flexible inspirée des techniques de stippling qui génère automatiquement, grâce à un algorithme d'optimisation, des courbes d'échantillonnage non-cartésiennes optimisées et compatibles avec les contraintes hardware de l'IRM en termes d'amplitude de gradient maximale et d'accélération maximale. Ces courbes d'échantillonnage sont conçues pour répondre à des critères clés pour un échantillonnage optimal : une distribution contrôlée des échantillons et une couverture de l'espace-k localement uniforme. Avant de s'engager dans des acquisitions, nous avons vérifié que notre système de gradient était bien capable d'exécuter ces trajectoires complexes. Nous avons implémenté une méthode de mesure de phase et avons observé une très bonne adéquation entre trajectoires prescrites et mesurées.Enfin, en alliant une efficacité d'échantillonnage avec le compressed sensing et l'imagerie parallèle, les trajectoires SPARKLING ont permis de réduire jusqu'à 20 fois le temps d'acquisition d'un examen IRM T ₂ * par rapport aux acquisitions cartésiennes de référence, sans détérioration de la qualité d'image. Ces résultats expérimentaux ont été obtenus à 7 Tesla pour de l'imagerie cérébrale in vivo. Par rapport aux stratégies d'échantillonnage non-cartésiennes usuelles (spirale et radiale), la technique proposée a également permis d'obtenir une qualité d'image supérieure. Enfin, l'approche proposée a été étendue à l'imagerie 3D et appliquée à 3 Tesla pour laquelle des résultats préliminaires ex vivo à une résolution isotrope de 0.6 mm suggèrent la possibilité d'atteindre des facteurs d'accélération très élevés jusqu'à 60 pour la pondération T ₂ * et l'imagerie pondérée en susceptibilité.

During the experiment, ten types of sparkling wine were analyzed: five white semi ‒ sweet sparkling wine drinks and five types of sweet sparkling wine. It was determined that the physical chemical characteristics and organoleptic characteristics of white semi-sweet and sweet sparkling wine varied depending on the type of wine, while the factors analyzed (sweet/semi-sweet and non-flavored/flavored) had a statistically significant effect on the sugar content, titric acid, free sulfur dioxide, total sulfur dioxide, extract, CO2 pressure, methyl alcohol, energy values (p ≤ 0.05). Depending on the type of wine drink, by sampling and recording emotional facial expressions in the FaceReader software, they varied depending on the factors analyzed (p ≤ 0.05) and the expression "happy" is different from 11.50 percent up to 23.61 percent, and the highest was captured by tasting sample No. 10. The links between the quality of the white semi ‒ sweet and sweet sparkling wine drink were not statistically reliable. In conclusion, it can be argued that the wine making process is complex in terms of biochemical changes, and the final quality can be determined not only by technological factors but also by interconnections between individual compounds.

The price of wine reflects the various features that differentiate each bottle. This study is aimed at analyzing the determinants of California wine prices. A hedonic price model is estimated using data collected between 2004 and 2015 from the Wine Spectator, with a total of 4,693 individual wines, focusing on type, age, critical points, and variables related to the origin. The impact of geographic production of origin from Bay Area/Central Coast, Carneros, Napa, Mendocino/Lake, and South Coast is analyzed. An important aspect of this analysis is to investigate whether the type of wine is important, and if any price premium regarding to the type (still and sparkling) is changing, holding quality and quantity constant. The main findings suggest California wine prices are determined by time related variables such as age. The expert points given by the Wine Spectator also have a significant impact on prices.

Made available in DSpace on 2017-07-21T18:53:11Z (GMT). No. of bitstreams: 1 Resultados e Discussoes.pdf: 625763 bytes, checksum: 0fcdae03788e2bcb5f1e0834574ae458 (MD5) Previous issue date: 2009-05-27 The use of musts made with apples discarded during classification to in natura trade and the artificial gasification of the fermented, undertake the quality of Brazilian cider. The fermentation process used results in carbon dioxide loss and, consequently, aromatics compounds with large importance to the sensorial attributes of the fermented as well. The product quality could be improved by the use of selected apples cultivars and by the realization of natural gasification process. The objective of this research was the assessment of sparkling obtained by natural gasification process, by the use of selected apples cultivars. In the sparkling elaboration were used apples of Catarina, Granny Smith and Pink Lady cultivars (2007/2008 crop), which were selected because they present physic-chemical characteristics suitable to the process. Six varietal sparklings were elaborated, all by the Champenoise method, and four mixture sparklings, elaborated from a must made by a mixture of the three cultivars, in which the proportions were defined by a statistic planning. The mixture sparklings were elaborated by four different methods: process Chempenoise, artificial gasification, Asti and Charmat, being the two last made in pilot scale. All sparklings were evaluated by physic-chemical and chromatographic analysis, as well as oenology tasting, being classified by the Principal Compounds Analysis (PCA) statistical method. The PCA use, besides the results obtained by the oenology tasting, allowed the varietal sparklings to be classified in groups made by the apple cultivar used in the elaboration and by the glucose source used in the supplementation of the base-fermented. In this way, was evidenced the significant difference between them and, therefore, the need of elaboration of a mixture so that the characteristics of each cultivar would be demonstrated in a unique must. The use of statistic planning allowed the formulation of mixture must with physic-chemical characteristics adapted to the sparkling elaboration, with were evaluated and compared to a commercial apple sparkling made in Switzerland by the Champenoise method. In the oenology tasting, in all the resultant sparklings was identify the lack of freshness and limpidity, indicating the need of the use of apples with higher acidity and more effective filtration processess. The differentiation between the varietal, mixture and commercial sparkling was possible by the use of PCA, on which the chromatographic parameters were the mainly responsible by the differentiation between the varietal and mixture groups, whilst the physic-chemical parameters, specially acidity and turbidity, were the mainly responsible by the isolation of the commercial sparkling in a third group. It wasn’t evidenced significant difference between the elaboration process. The use of natural gasification process and musts elaborated by mixture of selected apple cultivars were promising measures in the obtention of quality natural apple sparklings. A utilização de mostos formulados por maçãs descartadas na classificação para o comércio in natura e a gaseificação artificial do fermentado comprometem a qualidade das sidras brasileiras. O processo de fermentação utilizado resulta na perda do gás carbônico e, consequentemente, de compostos aromáticos de grande importância aos atributos sensoriais do fermentado. A qualidade do produto poderia ser aprimorada pela utilização de cultivares de maçãs selecionados e pela realização de processos naturais de gaseificação. A avaliação de espumantes obtidos por processos de gaseificação natural, pelo uso de cultivares de maçã selecionados, foi o objetivo deste trabalho. Na elaboração dos espumantes foram utilizadas maçãs dos cultivares Catarina, Granny Smith e Pink Lady das safras de 2007/2008, selecionadas por apresentarem características físico-químicas adequadas ao processamento. Foram elaborados seis espumantes varietais, todos pelo método Champenoise, e quatro espumantes de mistura, elaborados a partir de um mosto formulado pela mistura dos três cultivares, no qual as proporções foram definidas por um planejamento estatístico. Os espumantes de mistura foram elaborados por quatro diferentes métodos, processos Champenoise, gaseificação artificial, Asti e Charmat, sendo os dois últimos realizados em escala piloto. Todos os espumantes foram avaliados por análises físico-químicas, cromatográfica e degustação enológica e classificados pelo método estatístico Análise por Componentes Principais – PCA. A utilização da PCA, em conjunto com os resultados obtidos pela degustação enológica, permitiram classificar os espumantes varietais em grupos formados pelo cultivar de maçã utilizados em sua elaboração e pela fonte de glucose utilizada na suplementação de seus fermentados-base, de modo que foi evidenciada a diferença significativa entre eles e, portanto, a necessidade de elaboração de uma mistura para que as características de cada cultivar fossem demonstradas em um mosto único. A utilização do planejamento estatístico permitiu a formulação de um mosto mistura com características físico-químicas adaptadas a sua aplicação na elaboração dos espumantes, os quais foram avaliados e comparados com um espumante de maçã comercial produzido na Suíça pelo método Champenoise. Na degustação enológica em todos os espumantes foi identificada a falta de frescor e limpidez, indicando a necessidade do uso de maçãs com maior acidez e de processos mais eficazes de filtração. A diferenciação entre os espumantes varietais, de mistura e comercial foi possível pela utilização da PCA, na qual os parâmetros cromatográficos foram os principais responsáveis pela diferenciação entre os grupos varietais e de mistura, ao passo que os parâmetros físico-químicos, em especial a acidez e turbidez, foram os principais responsáveis pelo isolamento do espumante comercial num terceiro grupo. Não foi evidenciada diferença significativa entre os processos de elaboração. A utilização de processos naturais de gaseificação e de mostos formulados por misturas de cultivares de maçã selecionados foram medidas promissoras na obtenção de espumantes naturais de maçã de qualidade.