Search

Aquest treball engloba i reflecteix els coneixements adquirits en el Màster Universitari d’Enginyeria Industrial (MUEI), concretament en l’especialitat d’estructures i construcció. Serveix com a forma de plasmar els conceptes i mètodes apresos en aquesta etapa. Aquest projecte de final de màster es centra en el disseny i càlcul de l’estructura d’un edifici industrial. Es portarà a terme una hipotètica remodelació d’un edifici polivalent de la ciutat d’Olot (edifici Pavelló Firal). Aquest edifici, actualment acull actes públics de tota mena: activitats esportives, fires, esdeveniments i actes públics... En aquest treball es fa una proposta d’un possible edifici que, no només modernitzaria l’edifici, a nivell constructiu, sinó que n’ampliaria la seva capacitat d’una forma considerable. Aquí es posaran en pràctica els conceptes adquirits a les diferents assignatures del màster, però sobretot a les assignatures de l’especialitat d’estructures i construcció (Teoria d’estructures, Sistemes constructius, Estructures de Formigó, Anàlisi estructural avançat i Estructura metàl·lica i mixta). La primera part del treball consisteix en una breu introducció a les estructures, els diferents tipus existents i els materials que les composen. Es fa una comparació entre els diferents estils, i s’especifiquen els diferents avantatges i inconvenients de cada una. A la segona part del treball es fa el disseny i càlcul de l’estructura de l’edifici esmentat. Es determinen les dimensions, elements que el composen, les càrregues que hi actuen... Tot això porta a una proposta d’estructura, i a un càlcul, combinant mètodes manuals i càlcul per simulació, per tal de verificar-la

Aquest treball de final de grau sorgeix d’unir dos dels temes de gran interès per part meva: la resistència de materials i l’esquí. Aquest projecte es centra en el disseny, càlcul, simulació i construcció d’uns esquís. Es realitzaran càlculs teòrics amb els coneixements i conceptes adquirits a les assignatures de Resistència de materials i Ampliació de resistència de materials. La primera part del treball consisteix en un anàlisi i explicació de tots els elements que intervenen en el funcionament, comportament i construcció d’un esquí. Destacant els materials constructius, la seva influència i aportació al comportament d’aquest sobre la neu... així com els diferents mètodes constructius i geometries possibles i com aquestes condicionen la resposta de l’esquí. Finalment es fa un estudi per determinar quines són les forces presents en un esquí quan aquest està sobre la neu en diferents situacions. A la segona part es fa un disseny preliminar de l’esquí segons els criteris de disseny escollits. Se’n determina la geometria, mides, forma... A continuació es fa una selecció dels materials que s’utilitzaran en la construcció de l’esquí, determinant-ne les seves característiques i propietats mecàniques. Seguidament es fa un càlcul dels esforços i tensions presents en l’esquí en les diferents situacions especificades. Aquests càlculs són verificats mitjançant el programari de càlcul ANSYS. Finalment, a la tercera part, es fan algunes optimitzacions pel que fa a materials, i geometria de l’esquí, i, finalment, es porta a terme la seva construcció seguint els criteris i resultats obtinguts al llarg del treball

The diverse pneumococcal diseases are associated with different pneumococcal lineages, or clonal complexes. Nevertheless, intra-clonal genomic variability, which influences pathogenicity, has been reported for surface virulence factors. These factors constitute the communication interface between the pathogen and its host and their corresponding genes are subjected to strong selective pressures affecting functionality and immunogenicity. First, the presence and allelic dispersion of 97 outer protein families were screened in 19 complete pneumococcal genomes. Seventeen families were deemed variable and were then examined in 216 draft genomes. This procedure allowed the generation of binary vectors with 17 positions and the classification of strains into surfotypes. They represent the outer protein subsets with the highest inter-strain discriminative power. A total of 116 non-redundant surfotypes were identified. Those sharing a critical number of common protein features were hierarchically clustered into 18 surfogroups. Most clonal complexes with comparable epidemiological characteristics belonged to the same or similar surfogroups. However, the very large CC156 clonal complex was dispersed over several surfogroups. In order to establish a relationship between surfogroup and pathogenicity, the surfotypes of 95 clinical isolates with different serogroup/serotype combinations were analyzed. We found a significant correlation between surfogroup and type of pathogenic behavior (primary invasive, opportunistic invasive, and non-invasive). We conclude that the virulent behavior of S. pneumoniae is related to the activity of collections of, rather than individual, surface virulence factors. Since surfotypes evolve faster than MLSTs and directly reflect virulence potential, this novel typing protocol is appropriate for the identification of emerging clones.

Ce dossier s’est déroulé dans une démarche collaborative entre trois écoles de Nancy, l’Ecole Européenne d’Ingénieurs en Génie des Matériaux, l’Ecole Nationale Supérieure d’Architecture et l’Ecole Nationale Supérieure en Génie des Systèmes et de l’Industrie. Nous avons travaillé durant 10 mois au nombre de 10 étudiants dans le cadre de l’atelier GAÏA. Cet atelier nous a mis en relation avec le CROUS Loraine afin de traiter d’un sujet essentiel pour les étudiants aujourd’hui, leur logement. Après de nombreuses tables rondes avec l’ensemble des participants ainsi qu’avec nos professeurs encadrant, nous avons proposé la possible réhabilitation de la résidence Saurupt du CROUS, support de notre étude. Avec des connaissances partagés allant du traitement de données statistiques, des calculs de thermique jusqu’à l’élaboration de nouvelles organisations spatiales, l’enjeux a été de construire un projet cohérent et éclairé pour les futurs étudiants et doctorants de demain

Capsular switching allows pre-existing clones of Streptococcus pneumoniae expressing vaccine serotypes to escape the vaccine-induced immunity by acquisition of capsular genes from pneumococci of a non-vaccine serotype. Here, we have analysed the clonal composition of 492 clinical isolates of serotype 11A causing invasive disease in Spain (2000–2012), and their ability to evade the host immune response. Antibiograms, serotyping and molecular typing were performed. The restriction profiles of pbp2x, pbp1a and pbp2b genes were also analysed. Interaction with the complement components C1q, C3b, C4BP, and factor H was explored whereas opsonophagocytosis assays were performed using a human cell line differentiated to neutrophils. Biofilm formation and the polymorphisms of the major autolysin LytA were evaluated. The main genotypes of the 11A pneumococci were: ST62 (447 isolates, 90.6%), followed by ST6521 (35 isolates, 7.3%) and ST838 (10 isolates, 2.1%). Beta lactam resistant serotype 11A variants of genotypes ST838 and ST6521 closely related to the Spain9V-ST156 clone were first detected in 2005. A different pattern of evasion of complement immunity and phagocytosis was observed between genotypes. The emergence of one vaccine escape variant of Spain9V-ST156 (ST652111A), showing a high potential to avoid the host immune response, was observed.In addition, isolates of ST652111A showed higher ability to produce biofilms than ST83811A or ST6211A, which may have contributed to the emergence of this PEN-resistant ST652111A genotype in the last few years. The emergence of penicillin-resistant 11A invasive variants of the highly successful ST156 clonal complex merits close monitoring.

Biofilm formation by nontypeable (NT) Haemophilus influenzae remains a controversial topic. Nevertheless, biofilm-like structures have been observed in the middle-ear mucosa of experimental chinchilla models of otitis media (OM). To date, there have been no studies of biofilm formation in large collections of clinical isolates. This study aimed to investigate the initial adhesion to a solid surface and biofilm formation by NT H. influenzae by comparing isolates from healthy carriers, those with noninvasive respiratory disease, and those with invasive respiratory disease. We used 352 isolates from patients with nonbacteremic community-acquired pneumonia (NB-CAP), chronic obstructive pulmonary disease (COPD), OM, and invasive disease and a group of healthy colonized children. We then determined the speed of initial adhesion to a solid surface by the BioFilm ring test and quantified biofilm formation by crystal violet staining. Isolates from different clinical sources displayed high levels of biofilm formation on a static solid support after growth for 24h. We observed clear differences in initial attachment and biofilm formation depending on the pathology associated with NT H. influenzae isolation, with significantly increased biofilm formation for NT H. influenzae isolates collected from patients with invasive disease and OM compared with NT H. influenzae isolates from patients with NB-CAP or COPD and healthy colonized subjects. In all cases, biofilm structures were detached by proteinase K treatment, suggesting an important role for proteins in the initial adhesion and static biofilm formation measured by crystal violet staining.

Antibiotic resistance in Streptococcus pneumoniae has increased worldwide by the spread of a few clones. Fluoroquinolone resistance occurs mainly by alteration of their intracellular targets, the type II DNA topoisomerases, which is acquired either by point mutation or by recombination. Increase in fluoroquinolone-resistance may depend on the balance between antibiotic consumption and the cost that resistance imposes to bacterial fitness. In addition, pneumococcal prophages could play an important role. Prophage induction by fluoroquinolones was confirmed in 4 clinical isolates by using Southern blot hybridization. Clinical isolates (105 fluoroquinolone-resistant and 160 fluoroquinolone-susceptible) were tested for lysogeny by using a PCR assay and functional prophage carriage was studied by mitomycin C induction. Fluoroquinolone-resistant strains harbored fewer inducible prophages (17/43) than fluoroquinolone-susceptible strains (49/70) (P = 0.0018). In addition, isolates of clones associated with fluoroquinolone resistance [CC156 (3/25); CC63 (2/20), and CC81 (1/19)], had lower frequency of functional prophages than isolates of clones with low incidence of fluoroquinolone resistance [CC30 (4/21), CC230 (5/20), CC62 (9/21), and CC180 (21/30)]. Likewise, persistent strains from patients with chronic respiratory diseases subjected to fluoroquinolone treatment had a low frequency of inducible prophages (1/11). Development of ciprofloxacin resistance was tested with two isogenic strains, one lysogenic and the other non-lysogenic: emergence of resistance was only observed in the non-lysogenic strain. These results are compatible with the lysis of lysogenic isolates receiving fluoroquinolones before the development of resistance and explain the inverse relation between presence of inducible prophages and fluoroquinolone-resistance. © 2014 López et al.