Flexographic printing is a common printing method in the packaging field. The printing method is characterized primarily by the flexible printing plate and the low viscosity inks which make it suitable for use on almost any substrate. The object of this study was to obtain further knowledge of the some important mechanisms of flexographic printing and how they influence the print quality. The thesis deals with printing primarily on board and liner but also on newsprint with water-borne ink using a full-scale flexographic central impression (CI) printing press. Several printing trials have been performed with a focus on the chemical interaction between the ink and substrate and the physical contact between the ink-covered printing plate and the substrate. Multicolour printing exposes the substrate to water from the water-containing ink. The emphasis was to investigate the relation between print quality and water-uptake of the paper surface with heat and water. Printing trials was carried out on substrates possessing a hydrophobic, and also a rather hydrophilic surface using a regular commercial water-borne ink. The favorable effect which water or surfactant solution had on the hydrophobic substrate with regard to print mottle could depend on its surface compressibility in combination with the hydrophobic nature of its surface that could affect the wetting properties. Conventional printing involves physical contact between plate and ink and between ink and substrate. A method for measuring the dynamic nip pressure using thin load cells is presented. Print quality was influenced by the plate material. A correction procedure taking into account the size of the sensor was developed in order to estimate the maximum dynamic pressure in the printing nip. An attempt was made to identify essential mechanical and chemical parameters, and also geometrical properties of the plate that affected print quality. Laboratory printing trials were carried out and a multivariate analysis was applied for evaluation of print quality data. The impact of the plate properties on print quality was evident. The essential properties of the plate that influence print quality were the small-scale roughness and long-scale roughness.

A vibration isolator is designed to reduce the vibration and structure borne noise transmitted from a vibratory source, such as machinery and equipment, to the supporting structure. The vibration and structure borne noise transmitted depends upon the dynamic properties of the foundation, the source mounting point and the vibration isolator. Therefore knowledge of the frequency dependent dynamic properties of vibration isolators is a necessary part of the acoustic prediction and control/reduction process. Vibration isolators may be characterised by measuring their four-pole parameters. A measurement procedure is proposed that employs the floating mass method, measures the direct forces and corrects for the errors introduced by the direct force measurement. Compared to the basic method, it extends the frequency limits of measurement in both directions. The development of a novel vibration isolator test facility that implements the proposed measurement procedure is described, and its satisfactory operation is experimentally demonstrated. The vibration isolator test facility is capable of characterizing vibration isolators commonly used in industrial and maritime applications, under service conditions. A method is proposed for measuring the four-pole parameters of a uni-directional asymmetrical vibration isolator under static load. The method is called the two masses method, and is suitable for determining the four???pole parameters of active vibration isolators with feedback control. The method is also applicable to uni-directional symmetrical and bi-directional symmetrical and bi-directional asymmetrical vibration isolators. It may be regarded as a universal method for characterising vibration isolators. Experimental data is presented and the method is validated. Modelling of vibration isolators is complicated by the highly non-linear nature of their rubber elements. The notion of an effective rubber cylinder is proposed to account for the barrelling of rubber elements under static load. Consequently, a general static compression model is proposed that applies to vibration isolators having unfilled and filled rubber elements of regular prismatic shapes. The model predicts the dependence of the four-pole parameters on the compression ratio of the rubber element. The predictions derived from the effective rubber cylinder and general static compression model agree excellently with experimental work of this study and other researchers.

Diss. (sammanfattning) Stockholm : Karol. inst., 2005. / Härtill 4 uppsatser.

Diss. (sammanfattning) Linköping : Linköpings universitet, 2004. / Härtill 4 uppsatser.

Thesis (doctoral)--Lund University, 1998. / Added t.p. with thesis statement inserted. Includes bibliographical references.

Submitted by Lara Oliveira (lara@ufersa.edu.br) on 2017-01-10T16:10:06Z No. of bitstreams: 1 IzabelMG_TESE.pdf: 880498 bytes, checksum: 2febd06d5341085eddd00966347b4504 (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2017-01-24T14:45:40Z (GMT) No. of bitstreams: 1 IzabelMG_TESE.pdf: 880498 bytes, checksum: 2febd06d5341085eddd00966347b4504 (MD5) / Made available in DSpace on 2017-03-21T14:50:07Z (GMT). No. of bitstreams: 1 IzabelMG_TESE.pdf: 880498 bytes, checksum: 2febd06d5341085eddd00966347b4504 (MD5) Previous issue date: 2016-02-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The melon cultivation in semi-arid northeast in consecutive cycles has generated problems caused by fungi inhabitants of the soil, such as Fusarium solani and M. cannonballus. The use of resistant cultivars is an interesting measure for the management of the disease. For this reason, it is important identify sources of resistance and study their inheritance. The objectives of this work were: a) to evaluate the reaction of melon accessions to F. solani f. sp. Cucurbitae; b) to evaluate the reaction of accessions and study the inheritance of resistance of accession AC-33 to M. cannonballus. In the first experiment, we evaluated twenty-one accessions in a completely randomized design in greenhouse. Two isolates were inoculated fifteen days after sowing by the toothpick. The assessment was done Thirty days after inoculation with a scale scored from zero to four. The accessions AC-01, AC-09, AC-42, AC-45, AC-50 and the cultivar 'Doublon' are the most promising materials for use in breeding programs for resistance to F. solani or as rootstocks. In the second experiment, sixteen accessions and line OF-02 were evaluated in a completely randomized design. We used the isolated MC-16 to infestation of a mixture (1:1:1) with soil, peat, and sand previously sterilized with the addition of a concentration of 20 u.f.c./g soil. The evaluation was performed at 45 days using a rating scale (1-5). In the third experiment, we investigated the inheritance of resistance of accession AC-33 crossed with line OF-02 (susceptible). We observed variability in the germplasm investigated for reaction to the fungus. The AC-33 is highly resistant to access M. cannonballus and its resistance is controlled by a major gene with additive and dominant effects and polygenes with additive effects / O cultivo do meloeiro no semiárido nordestino em ciclos consecutivos tem gerado problemas causados por fungos habitantes do solo, como Fusarium solani e Monosporascus cannonballus. O uso de cultivares resistentes é uma medida interessante para o manejo da doença. Em razão disso, é importante que fontes de resistência sejam identificadas e se conheça a herança da resistência. Os objetivos do presente trabalho foram: a) avaliar a reação de acessos de meloeiro a F. solani f. sp. cucurbitae e b) avaliar a reação de acessos e estudar a herança da resistência do acesso AC-33 a M. cannonballus. No primeiro experimento, foram avaliados 21 acessos em um delineamento inteiramente casualizado em casa-de-vegetação. Foram inoculados dois isolados, com o método do palito, aos 15 dias após a semeadura. A avaliação dos acessos foi realizada 30 dias após a inoculação, com uma escala de 0 a 4. Os acessos AC-01, AC-09, AC-42, AC-45 e AC-50 e a cultivar ‘Doublon’ são os materiais mais promissores para uso em programas de melhoramento genético visando à resistência a F. solani ou como porta-enxertos. No segundo experimento, foram avaliados 16 acessos e a linhagem OF-02 em um delineamento inteiramente casualizado. Utilizou-se o isolado MC-16 para infestação de mistura em volume de 1:1:1 de terra, turfa e areia, previamente esterilizada com a adição de uma concentração 20 u.f.c./g de solo. A avaliação foi realizada aos 45 dias utilizando uma escala de notas (1 a 5). No terceiro experimento, investigou-se a herança da resistência do acesso AC-33 (resistente) cruzado com a linhagem OF-02 (suscetível). Observou-se a existência de variabilidade no germoplasma investigado para reação ao fungo. O acesso AC-33 é altamente resistente a M. cannonballus e sua resistência é controlada por um gene maior de efeito aditivo e dominante e poligenes de efeitos aditivos / 2017-01-10

The aim of this study was to characterize the replication of tick borne encephalitis virus in mouse macrophages and investigate the influence of tick saliva derived from Ixodes ricinus on the viral replication. Moreover, the effect of interferon (the member of type I interferons) and nitric oxide on virus replication was studied.

Além de micro-organismos causadores de Doenças Transmitidas por Alimentos, a presença de bactérias resistentes a antimicrobianos deve ser monitorada para garantir a inocuidade da carne suína. O objetivo deste estudo foi determinar a frequência de Salmonella enterica e Listeria monocytogenes em amostras de fezes e carcaças suínas, e avaliar a resistência a antimicrobianos entre isolados de Escherichia coli provenientes das mesmas origens. Dois ciclos de amostragem foram conduzidos em três matadouros-frigoríficos localizados no Estado de Santa Catarina. Em cada ciclo, fezes colhidas a partir do piso da pocilga de espera, e suabes de superfície de 14 carcaças no pré-resfriamento foram amostrados em três lotes abatidos. As amostras foram analisadas quanto à presença dos gêneros Salmonella e Listeria e foi determinada a média de coliformes totais nas carcaças em cada ciclo de amostragem. Isolados de E. coli foram avaliados quanto à frequência de resistência a antimicrobianos pelo método de difusão em ágar. Das fezes colhidas 83,33% (15/18) apresentaram Salmonella sp., e 5,5% (1/18) L. monocytogenes. Do total de 252 carcaças, 27,38% (69/252) foram positivas para Salmonella sp. e 19,84% (50/252) para L. monocytogenes. Em 3,17% (8/252) carcaças houve o isolamento concomitante dos dois patógenos. Os isolados de Salmonella foram classificados em dez sorovares distintos, predominando S. Typhimurium nas fezes e S. Derby nas carcaças. A média de coliformes totais nas carcaças variou de 5,27x101 a 9,73x103. Em relação ao teste de resistência frente a antimicrobianos realizado em isolados de E. coli, observou-se maior frequência de resistência em isolados de fezes do que nos originados de carcaças, com diferença significativa para tetraciclina (P<0,001), ampicilina (P<0,001) e sulfonamida (P=0,022). Entre os matadouros-frigoríficos, houve diferença na frequência de isolados resistentes para florfenicol e gentamicina (P<0,05) em isolados de fezes, e para ácido nalidíxico, sulfonamida e tetraciclina (P<0,05) em isolados de carcaça. A elevada frequência de resistência a princípios ativos utilizados na suinocultura indicam pressão de seleção exercida pelo uso indiscriminado de antimicrobianos e podem resultar na co-seleção de genes de resistência localizados em cassetes gênicos. Os isolados multi-resistentes foram mais presentes nas fezes quando comparados com carcaças (P<0,001), sugerindo que há diminuição da frequência de isolados resistentes ao longo do processo de abate. Com os resultados obtidos no presente estudo, conclui-se que maior atenção deve ser dispensada ao monitoramento das etapas do abate para identificar possíveis falhas que estão determinando a presença de carcaças contaminadas na fase de pré-resfriamento, além da necessidade do uso mais prudente dos antimicrobianos na suinocultura. / Besides the contamination of pig carcasses with food borne pathogens, the presence of bacteria resistant to antimicrobials represent a new hazard that should be monitored in order to ensure the safety of pork. This study aimed at determining the frequency of Salmonella enterica and Listeria monocytogenes in samples of swine feces and carcasses, and at evaluating antimicrobial resistance among isolates of Escherichia coli from the same origin. Two cycles of sampling were carried out in three slaughterhouses located in the State of Santa Catarina. For each cycle, feces collected from the floor of the pen, and surface swabs of 14 carcasses at the pre-chill were sampled in three slaughtered batches. The samples were analyzed for the presence of Salmonella and Listeria, and the average of total coliforms on carcasses in each sampling cycle was determined. Isolates of E. coli were evaluated for the frequency of antimicrobial resistance by the agar diffusion method. Out of the feces collected 83.33% (15/18) had Salmonella sp., and 5.5% (1/18) L. monocytogenes. Out of the total of 252 carcasses, 19.84% (50/252) were positive for Salmonella sp. and 27.38% (69/252) for L. monocytogenes. In 3.96% (10/252) carcasses both pathogens were isolated. Salmonella isolates were classified in ten serovars, predominantly S. Typhimurium in the feces and S. Derby on the carcasses. The average of total coliforms on carcasses varied between 5.27x101 to 9.73x103. Regarding the antimicrobial resistance tests carried out in isolates of E. coli, we observed a higher frequency of resistance in isolates from feces than from carcasses, with a significant difference for tetracycline (P<0.001), ampicillin (P<0.001) and sulfonamide (P=0.022). Among the slaughterhouses, there were differences in the frequency of resistance against florfenicol and gentamicin (P<0.05) in isolates from feces, and against nalidixic acid, sulfonamide and tetracycline (P<0.05) in isolated from carcasses. The high frequencies of resistance to drugs used in swine production indicate selection pressure exerted by the indiscriminate use of antibiotics and may result from co-selection of resistance genes located in gene cassettes. Multi-resistant isolates were more frequent in the feces compared to carcasses (P<0.001), suggesting that there is a decrease in the frequency of resistant isolates during the slaughter process. From the results obtained in this study, it is concluded that more attention should be paid to monitoring the stages of the slaughter in order to identify possible flaws that are causing the presence of contaminated carcasses at the pre-chill, as well as the need for more prudent use of antimicrobials in swine production.

Le but de cette thèse est de trouver des bornes supérieures pour les valeurs propres des opérateurs naturels agissant sur les fonctions d’une variété compacte (M; g). Nous étudions l’opérateur de Laplace–Beltrami et des opérateurs du type laplacien. Dans le cas du laplacien, deux aspects sont étudiés. Le premier aspect est d’étudier des relations entre la géométrie intrinsèque et les valeurs propres du laplacien. Nous obtenons des bornes supérieures ne dépendant que de la dimension et d’un invariant conforme qui s’appelle le volume conforme minimal. Asymptotiquement, ces bornes sont consistantes avec la loi de Weyl. Elles améliorent également les résultats de Korevaar et de Yang et Yau. La méthode employée est intéressante en soi. Le deuxième aspect est d’étudier la relation entre la géométrie extrinsèque et les valeurs propres du laplacien agissant sur des sous-variétés compactes de RN et de CPN. Nous étudions un invariant extrinsèque qui s’appele l’indice d’intersection. Pour des sous-variétés compactes de RN, nous généralisons les résultats de Colbois, Dryden et El Soufi et obtenons des bornes supérieures qui sont stables par des petites perturbations. Pour des sous-variétés de CPN, nous obtenons une borne supérieure ne dépendant que du degré des sous-variétés. Pour des opérateur du type laplacien, une modification de notre méthode donne des bornes supérieures pour les valeurs propres des opérateurs de Schrödinger en termes du volume conforme minimal et de l’intégrale du potentiel. Nous obtenons également les bornes supérieures pour les valeurs propres du laplacien de Bakry–Émery dépendant d’invariants conformes. / The purpose of this thesis is to find upper bounds for the eigenvalues of natural operators acting on functions on a compact Riemannian manifold (M; g) such as the Laplace–Beltrami operator and Laplace-type operators. In the case of the Laplace-Beltrami operator, two aspects are investigated: The first aspect is to study relationships between the intrinsic geometry and eigenvalues of the Laplacian operator. In this regard, we obtain upper bounds depending only on the dimension and a conformal invariant called min-conformal volume. Asymptotically, these bounds are consistent with the Weyl law. They improve previous results by Korevaar and Yang and Yau. The method which is introduced to obtain the results, is powerful and interesting in itself. The second aspect is to study the interplay of the extrinsic geometry and eigenvalues of the Laplace–Beltrami operator acting on compact submanifolds of RN and of CPN. We investigate an extrinsic invariant called the intersection index studied by Colbois, Dryden and El Soufi. For compact submanifolds of RN, we extend their results and obtain upper bounds which are stable under small perturbation. For compact submanifolds of CPN, we obtain an upper bound depending only on the degree of submanifolds. For Laplace type operators, a modification of our method lead to have upper bounds for the eigenvalues of Schrödinger operators in terms of the min-conformal volume and integral quantity of the potential. As another application of our method, we obtain upper bounds for the eigenvalues of the Bakry–Émery Laplace operator depending on conformal invariants.

L’étude des aérosols stratosphériques est importante pour comprendre le bilan radiatif terrestre. A l’heure actuelle, notre représentation des différents types de particules stratosphériques et leurs répartitions spatiale et temporelle n’est pas complète. Au cours de cette thèse, nous tentons de montrer que la mesure de la concentration en particules sous ballon météorologique au moyen d’un nouveau mini compteur de particules, le LOAC, pourrait permettre de rendre compte de la possible variabilité locale du contenu en aérosols stratosphériques dans la gamme de taille 0,2 à 100 μm en diamètre. La première partie de ce travail consiste à caractériser plus précisément les performances du LOAC sous ballon météorologique appliqué à la mesure en stratosphère. La seconde partie propose une analyse comparée du contenu en aérosols stratosphériques obtenu par LOAC, à partir de lâchers de ballons en France régulièrement depuis 3 ans et plus ponctuellement à l’étranger dans des situations particulières (volcan, mousson), et par d’autres types de données (Observations spatiales, lidar sol et simulation globale). Nous montrons alors que l’instrument possède une limite de détection rendant difficile la mesure des particules submicroniques lors de période de fond en moyenne stratosphère pour des concentrations de l’ordre d’une particule par cm3. Dans sa version actuelle, le LOAC permet de documenter les panaches volcaniques en troposphère ainsi qu’en basse stratosphère. En perspective, nous proposons des directions pour la calibration et l’analyse des futures données d’une nouvelle génération de l’instrument en développement. / The study of the stratospheric aerosols is important to our understanding of the terrestrial radiative budget. Our current comprehension of the different types of stratospheric particles and their spatial and temporal distribution is incomplete. In the present study, we try to show that measuring particle concentrations by the means of a new balloon-borne miniature particle counter, the LOAC, may allow us to determine the local variability in stratospheric aerosols in the size range 0.2 – 100 μm in diameter. In that respect, the PhD thesis consists of a first phase of a more accurate characterisation of the LOAC’s performances under balloon-borne measurement. A second phase consists of comparative analysis of stratospheric aerosol content based on a LOAC dataset obtained during a continuous campaign of balloon launches in France, along with some occasional flights abroad under particular circumstances (volcanic eruption, monsoon). Thus we show that the LOAC has a detection limit that restricts the measurement of submicronic particles in volcanic quiescent periods for concentrations lower than typically 1 particle per cm3. In its current version, the LOAC allows us to characterise aerosols in volcanic plumes in the troposphere and lower stratosphere. And, further, we propose directions concerning possible calibration and analysis strategies for the future data from the next generation of the LOAC currently in development.