782 resultados para STRAIN TECHNOLOGIES


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BACKGROUND: Ethiopia ranks seventh in the list of 22 high tuberculosis (TB) burden countries, with an incidence rate of 379 cases per 100 000 population for TB all forms. However, information on the genomic diversity of Mycobacterium tuberculosis in Ethiopia is limited. OBJECTIVE: To investigate the molecular characteristics of M. tuberculosis strains implicated in pulmonary TB in the study area. METHODS AND RESULTS: A cross-sectional study was conducted using socio-demographic, clinical and culture data combined with molecular typing analysis. The proportion of TB and M. tuberculosis isolates was not associated with risk factors (P > 0.05). Of 99 sputum samples, 80.8% were culture-positive. Speciation of isolates showed that 88.8% were M. tuberculosis. Further characterisation led to the identification of 27 different spoligotype patterns of M. tuberculosis; the most dominant shared types were SIT149, SIT53 and SIT54. Of the 27 strains, three strains were new and were reported to the SITVIT database. More than two thirds of the strains belonged to the Euro-American lineage. CONCLUSION: This study shows the presence of several clusters and new strains of M. tuberculosis circulating in pulmonary TB patients in the study area, suggesting recent transmission. Nationwide studies are recommended to map the population structure of M. tuberculosis and set control measures.

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State University Audit Report - Report Letter

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Of the approximately 25,000 bridges in Iowa, 28% are classified as structurally deficient, functionally obsolete, or both. Because many Iowa bridges require repair or replacement with a relatively limited funding base, there is a need to develop new bridge materials that may lead to longer life spans and reduced life-cycle costs. In addition, new and effective methods for determining the condition of structures are needed to identify when the useful life has expired or other maintenance is needed. Due to its unique alloy blend, high-performance steel (HPS) has been shown to have improved weldability, weathering capabilities, and fracture toughness than conventional structural steels. Since the development of HPS in the mid-1990s, numerous bridges using HPS girders have been constructed, and many have been economically built. The East 12th Street Bridge, which replaced a deteriorated box girder bridge, is Iowa’s first bridge constructed using HPS girders. The new structure is a two-span bridge that crosses I-235 in Des Moines, Iowa, providing one lane of traffic in each direction. A remote, continuous, fiber-optic based structural health monitoring (SHM) system for the bridge was developed using off-the-shelf technologies. In the system, sensors strategically located on the bridge collect raw strain data and then transfer the data via wireless communication to a gateway system at a nearby secure facility. The data are integrated and converted to text files before being uploaded automatically to a website that provides live strain data and a live video stream. A data storage/processing system at the Bridge Engineering Center in Ames, Iowa, permanently stores and processes the data files. Several processes are performed to check the overall system’s operation, eliminate temperature effects from the complete strain record, compute the global behavior of the bridge, and count strain cycles at the various sensor locations.

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The Helvetic nappe system in Western Switzerland is a stack of fold nappes and thrust sheets em-placed at low grade metamorphism. Fold nappes and thrust sheets are also some of the most common features in orogens. Fold nappes are kilometer scaled recumbent folds which feature a weakly deformed normal limb and an intensely deformed overturned limb. Thrust sheets on the other hand are characterized by the absence of overturned limb and can be defined as almost rigid blocks of crust that are displaced sub-horizontally over up to several tens of kilometers. The Morcles and Doldenhom nappe are classic examples of fold nappes and constitute the so-called infra-Helvetic complex in Western and Central Switzerland, respectively. This complex is overridden by thrust sheets such as the Diablerets and Wildhörn nappes in Western Switzerland. One of the most famous example of thrust sheets worldwide is the Glariis thrust sheet in Central Switzerland which features over 35 kilometers of thrusting which are accommodated by a ~1 m thick shear zone. Since the works of the early Alpine geologist such as Heim and Lugeon, the knowledge of these nappes has been steadily refined and today the geometry and kinematics of the Helvetic nappe system is generally agreed upon. However, despite the extensive knowledge we have today of the kinematics of fold nappes and thrust sheets, the mechanical process leading to the emplacement of these nappe is still poorly understood. For a long time geologist were facing the so-called 'mechanical paradox' which arises from the fact that a block of rock several kilometers high and tens of kilometers long (i.e. nappe) would break internally rather than start moving on a low angle plane. Several solutions were proposed to solve this apparent paradox. Certainly the most successful is the theory of critical wedges (e.g. Chappie 1978; Dahlen, 1984). In this theory the orogen is considered as a whole and this change of scale allows thrust sheet like structures to form while being consistent with mechanics. However this theoiy is intricately linked to brittle rheology and fold nappes, which are inherently ductile structures, cannot be created in these models. When considering the problem of nappe emplacement from the perspective of ductile rheology the problem of strain localization arises. The aim of this thesis was to develop and apply models based on continuum mechanics and integrating heat transfer to understand the emplacement of nappes. Models were solved either analytically or numerically. In the first two papers of this thesis we derived a simple model which describes channel flow in a homogeneous material with temperature dependent viscosity. We applied this model to the Morcles fold nappe and to several kilometer-scale shear zones worldwide. In the last paper we zoomed out and studied the tectonics of (i) ductile and (ii) visco-elasto-plastic and temperature dependent wedges. In this last paper we focused on the relationship between basement and cover deformation. We demonstrated that during the compression of a ductile passive margin both fold nappes and thrust sheets can develop and that these apparently different structures constitute two end-members of a single structure (i.e. nappe). The transition from fold nappe to thrust sheet is to first order controlled by the deformation of the basement. -- Le système des nappes helvétiques en Suisse occidentale est un empilement de nappes de plis et de nappes de charriage qui se sont mis en place à faible grade métamorphique. Les nappes de plis et les nappes de charriage sont parmi les objets géologiques les plus communs dans les orogènes. Les nappes de plis sont des plis couchés d'échelle kilométrique caractérisés par un flanc normal faiblement défor-mé, au contraire de leur flanc inverse, intensément déformé. Les nappes de charriage, à l'inverse se caractérisent par l'absence d'un flanc inverse bien défini. Elles peuvent être définies comme des blocs de croûte terrestre qui se déplacent de manière presque rigide qui sont déplacés sub-horizontalement jusqu'à plusieurs dizaines de kilomètres. La nappe de Mordes et la nappe du Doldenhorn sont des exemples classiques de nappes de plis et constitue le complexe infra-helvétique en Suisse occidentale et centrale, respectivement. Ce complexe repose sous des nappes de charriages telles les nappes des Diablerets et du Widlhörn en Suisse occidentale. La nappe du Glariis en Suisse centrale se distingue par un déplacement de plus de 35 kilomètres qui s'est effectué à la faveur d'une zone de cisaillement basale épaisse de seulement 1 mètre. Aujourd'hui la géométrie et la cinématique des nappes alpines fait l'objet d'un consensus général. Malgré cela, les processus mécaniques par lesquels ces nappes se sont mises en place restent mal compris. Pendant toute la première moitié du vingtième siècle les géologues les géologues ont été confrontés au «paradoxe mécanique». Celui-ci survient du fait qu'un bloc de roche haut de plusieurs kilomètres et long de plusieurs dizaines de kilomètres (i.e., une nappe) se fracturera de l'intérieur plutôt que de se déplacer sur une surface frictionnelle. Plusieurs solutions ont été proposées pour contourner cet apparent paradoxe. La solution la plus populaire est la théorie des prismes d'accrétion critiques (par exemple Chappie, 1978 ; Dahlen, 1984). Dans le cadre de cette théorie l'orogène est considéré dans son ensemble et ce simple changement d'échelle solutionne le paradoxe mécanique (la fracturation interne de l'orogène correspond aux nappes). Cette théorie est étroitement lié à la rhéologie cassante et par conséquent des nappes de plis ne peuvent pas créer au sein d'un prisme critique. Le but de cette thèse était de développer et d'appliquer des modèles basés sur la théorie de la méca-nique des milieux continus et sur les transferts de chaleur pour comprendre l'emplacement des nappes. Ces modèles ont été solutionnés de manière analytique ou numérique. Dans les deux premiers articles présentés dans ce mémoire nous avons dérivé un modèle d'écoulement dans un chenal d'un matériel homogène dont la viscosité dépend de la température. Nous avons appliqué ce modèle à la nappe de Mordes et à plusieurs zone de cisaillement d'échelle kilométrique provenant de différents orogènes a travers le monde. Dans le dernier article nous avons considéré le problème à l'échelle de l'orogène et avons étudié la tectonique de prismes (i) ductiles, et (ii) visco-élasto-plastiques en considérant les transferts de chaleur. Nous avons démontré que durant la compression d'une marge passive ductile, a la fois des nappes de plis et des nappes de charriages peuvent se développer. Nous avons aussi démontré que nappes de plis et de charriages sont deux cas extrêmes d'une même structure (i.e. nappe) La transition entre le développement d'une nappe de pli ou d'une nappe de charriage est contrôlé au premier ordre par la déformation du socle. -- Le système des nappes helvétiques en Suisse occidentale est un emblement de nappes de plis et de nappes de chaînage qui se sont mis en place à faible grade métamoiphique. Les nappes de plis et les nappes de charriage sont parmi les objets géologiques les plus communs dans les orogènes. Les nappes de plis sont des plis couchés d'échelle kilométrique caractérisés par un flanc normal faiblement déformé, au contraire de leur flanc inverse, intensément déformé. Les nappes de charriage, à l'inverse se caractérisent par l'absence d'un flanc inverse bien défini. Elles peuvent être définies comme des blocs de croûte terrestre qui se déplacent de manière presque rigide qui sont déplacés sub-horizontalement jusqu'à plusieurs dizaines de kilomètres. La nappe de Morcles and la nappe du Doldenhorn sont des exemples classiques de nappes de plis et constitue le complexe infra-helvétique en Suisse occidentale et centrale, respectivement. Ce complexe repose sous des nappes de charriages telles les nappes des Diablerets et du Widlhörn en Suisse occidentale. La nappe du Glarüs en Suisse centrale est certainement l'exemple de nappe de charriage le plus célèbre au monde. Elle se distingue par un déplacement de plus de 35 kilomètres qui s'est effectué à la faveur d'une zone de cisaillement basale épaisse de seulement 1 mètre. La géométrie et la cinématique des nappes alpines fait l'objet d'un consensus général parmi les géologues. Au contraire les processus physiques par lesquels ces nappes sont mises en place reste mal compris. Les sédiments qui forment les nappes alpines se sont déposés à l'ère secondaire et à l'ère tertiaire sur le socle de la marge européenne qui a été étiré durant l'ouverture de l'océan Téthys. Lors de la fermeture de la Téthys, qui donnera naissance aux Alpes, le socle et les sédiments de la marge européenne ont été déformés pour former les nappes alpines. Le but de cette thèse était de développer et d'appliquer des modèles basés sur la théorie de la mécanique des milieux continus et sur les transferts de chaleur pour comprendre l'emplacement des nappes. Ces modèles ont été solutionnés de manière analytique ou numérique. Dans les deux premiers articles présentés dans ce mémoire nous nous sommes intéressés à la localisation de la déformation à l'échelle d'une nappe. Nous avons appliqué le modèle développé à la nappe de Morcles et à plusieurs zones de cisaillement provenant de différents orogènes à travers le monde. Dans le dernier article nous avons étudié la relation entre la déformation du socle et la défonnation des sédiments. Nous avons démontré que nappe de plis et nappes de charriages constituent les cas extrêmes d'un continuum. La transition entre nappe de pli et nappe de charriage est intrinsèquement lié à la déformation du socle sur lequel les sédiments reposent.

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ABSTRACT Production of the polyketide antimicrobial metabolite 2,4-diacetyl-phloroglucinol (DAPG) is a key factor in the biocontrol activity of Pseudomonas fluorescens CHA0. Strain CHA0 carrying a translational phlA'-'lacZ fusion was used to monitor expression of the phl biosynthetic genes in vitro and in the rhizosphere. Expression of the reporter gene accurately reflected actual production of DAPG in vitro and in planta as determined by direct extraction of the antimicrobial compound. In a gnotobiotic system containing a clay and sand-based artificial soil, reporter gene expression was significantly greater in the rhizospheres of two monocots (maize and wheat) compared with gene expression in the rhizospheres of two dicots (bean and cucumber). We observed this host genotype effect on bacterial gene expression also at the level of cultivars. Significant differences were found among six additional maize cultivars tested under gnotobiotic conditions. There was no difference between transgenic maize expressing the Bacillus thuringiensis insecticidal gene cry1Ab and the near-isogenic parent line. Plant age had a significant impact on gene expression. Using maize as a model, expression of the phlA'-'lacZ reporter gene peaked at 24 h after planting of pregerminated seedlings, and dropped to a fourth of that value within 48 h, remaining at that level throughout 22 days of plant growth. Root infection by Pythium ultimum stimulated bacterial gene expression on both cucumber and maize, and this was independent of differences in rhizosphere colonization on these host plants. To our knowledge, this is the first comprehensive evaluation of how biotic factors that commonly confront bacterial inoculants in agricultural systems (host genotype, host age, and pathogen infection) modulate the expression of key biocontrol genes for disease suppression.

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Objective Investigating the educational technologies developed for promoting cardiovascular health in adults. Method Integrative review carried out in the databases of PubMed, SciELO and LILACS, with 15 articles selected. Results Over half (60%) of the studies were randomized clinical trials. The developed educational technologies were programs involving three strategies, with duration of one year, use of playful technologies with storytelling, computer programs or software for smartphones, and electronic brochure. These technologies resulted in reduction of blood pressure, weight, waist circumference, decreased hospitalizations and increased years of life. Conclusion The studies with better impact on the cardiovascular health of adults were those who brought the technology in the form of program and duration of one year.

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This article is based on a study of a reform in the organisation of maternity services in the United Kingdom, which aimed towards developing a more woman-centred model of care. After decades of fragmentation and depersonalisation of care, associated with the shift of birth to a hospital setting, pressure by midwives and mothers prompted government review and a relatively radical turnaround in policy. However, the emergent model of care has been profoundly influenced by concepts and technologies of monitoring. The use of such technologies as ultrasound scans, electronic foetal monitoring and oxytocic augmentation of labour, generally supported by epidural anaesthesia for pain relief, have accompanied the development of a particular ecological model of birth – often called active management –, which is oriented towards the idea of an obstetric norm. Drawing on analysis of women’s narrative accounts of labour and birth, this article discusses the impact on women’s embodiment in birth, and the sources of information they use about the status of their own bodies, their labour and that of the child. It also illustrates how the impact on women’s experiences of birth may be mediated by a relational model of support, through the provision of caseload midwifery care.

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ABSTRACT OBJECTIVE To identify the workloads present in the work activities of community health agents (CHAs) and the resulting strain processes. METHOD A descriptive, exploratory, cross-sectional and quantitative study conducted with 137 CHAs. Data were collected through a questionnaire and interview guided by the health surveillance software called SIMOSTE (Health Monitoring System of Nursing Workers), following the ethical codes of the current law. RESULTS In total, were identified 140 workloads involved in 122 strain processes, represented by the occurrence of health problems of the CHAs. The mechanical (55.00%) and biological (16.43%) loads stood out. The most common strain processes were the external causes of morbidity and mortality (62.31%) and diseases of the musculoskeletal system and connective tissue (10.66%). CONCLUSION From the identified overloads, it became evident that all workloads are present in the work process of CHAs, highlighting the mechanical load, represented mainly by external causes of morbidity and mortality that are related to occupational accidents.

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AIMS: To assess the impact of the biocontrol strain Pseudomonas fluorescens CHA0 on a collection of barley rhizosphere bacteria using an agar plate inhibition assay and a plant microcosm, focusing on a CHA0-sensitive member of the Cytophaga-like bacteria (CLB). METHODS AND RESULTS: The effect of strain CHA0 on a collection of barley rhizosphere bacteria, in particular CLB and fluorescent pseudomonads sampled during a growth season, was assessed by a growth inhibition assay. On average, 85% of the bacteria were sensitive in the May sample, while the effect was reduced to around 68% in the July and August samples. In the May sample, around 95% of the CLB and around 45% of the fluorescent pseudomonads were sensitive to strain CHA0. The proportion of CHA0-sensitive CLB and fluorescent pseudomonad isolates decreased during the plant growth season, i.e. in the July and August samples. A particularly sensitive CLB isolate, CLB23, was selected, exposed to strain CHA0 (wild type) and its genetically modified derivatives in the rhizosphere of barley grown in gnotobiotic soil microcosms. Two dry-stress periods were imposed during the experiment. Derivatives of strain CHA0 included antibiotic or exopolysaccharide (EPS) overproducing strains and a dry-stress-sensitive mutant. Despite their inhibitory activity against CLB23 in vitro, neither wild-type strain CHA0, nor any of its derivatives, had a major effect on culturable and total cell numbers of CLB23 during the 23-day microcosm experiment. Populations of all inoculants declined during the two dry-stress periods, with soil water contents below 5% and plants reaching the wilting point, but they recovered after re-wetting the soil. Survival of the dry-stress-sensitive mutant of CHA0 was most affected by the dry periods; however, this did not result in an increased population density of CLB23. CONCLUSIONS: CLB comprise a large fraction of barley rhizosphere bacteria that are sensitive to the biocontrol pseudomonad CHA0 in vitro. However, in plant microcosm experiments with varying soil humidity conditions, CHA0 or its derivatives had no major impact on the survival of the highly sensitive CLB strain, CLB23, during two dry-stress periods and a re-wetting period; all co-existed well in the rhizosphere of barley plants. SIGNIFICANCE AND IMPACT OF THE STUDY: Results indicate a lack of interaction between the biocontrol pseudomonad CHA0 and a sensitive CLB when the complexity increases from agar plate assays to plant microcosm experiments. This suggests the occurrence of low levels of antibiotic production and/or that the two bacterial genera occupy different niches in the rhizosphere.

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In this paper we argue that inventory models are probably not usefulmodels of household money demand because the majority of households does nothold any interest bearing assets. The relevant decision for most people is notthe fraction of assets to be held in interest bearing form, but whether to holdany of such assets at all. The implications of this realization are interesting and important. We find that(a) the elasticity of money demand is very small when the interest rate is small,(b) the probability that a household holds any amount of interest bearing assetsis positively related to the level of financial assets, and (c) the cost ofadopting financial technologies is positively related to age and negatively relatedto the level of education. Unlike the traditional methods of money demand estimation, our methodology allowsfor the estimation of the interest--elasticity at low values of the nominalinterest rate. The finding that the elasticity is very small for interest ratesbelow 5 percent suggests that the welfare costs of inflation are small. At interest rates of 6 percent, the elasticity is close to 0.5. We find thatroughly one half of this elasticity can be attributed to the Baumol--Tobin orintensive margin and half of it can be attributed to the new adopters or extensivemargin. The intensive margin is less important at lower interest rates and moreimportant at higher interest rates.

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Ce mémoire est l’occasion de partager le résultat de la mise en place de ce dispositif de formation à distance que nous avons mené dans l’université du Cap-Vert. Dans la première partie, nous décrirons la nature de la politique éducative au Cap-Vert. Nous contextualiserons les principes de l’installation de l’université publique dans ce pays, ainsi que les intentions d’innovation pédagogique de cette université. La deuxième partie portera un regard complémentaire sur l’utilisation des TIC et de l’internet dans l’enseignement/apprentissage d’une langue, cas du français langue étrangère, et nous nous inspirerons des théories constructiviste et socio-constructiviste. Finalement, la troisième partie détaillera toutes les étapes de la conception et de la mise en place du dispositif de formation à distance. Dans cette troisième partie, nous aborderons dans un premier temps la question des enjeux et des risques du e-Learning et nous présenterons notre mission dans le projet « e-Learning.cv » mené par l’université. Puis, dans un deuxième temps nous analyserons quelques cours que nous avons mis en ligne, en sachant qu’un cours en ligne n’est pas la simple reproduction d’un support pédagogique imprimé mais il offre à l’apprenant un environnement multimédia et interactif. Finalement dans un troisième temps nous essayerons de prendre un peu de recul pour faire une analyse critique de ce que nous avons réalisé et essayer par là même de dégager les perspectives pour améliorer le travail effectué.

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From a collection of yeast isolates isolated from patients in Tunisian hospitals between September 2006 and July 2010, the yeast strain JEY63 (CBS 12513), isolated from a 50-year-old male that suffered from oral thrush, could not be identified to the species level using conventional methods used in clinical laboratories. These methods include matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS), germ tube formation, and the use of CHROMagar Candida and metabolic galleries. Sequence analysis of the nuclear rRNA (18S rRNA, 5.8S rRNA, and 26S rRNA) and internal transcribed spacer regions (ITS1 and ITS2) indicated that the ribosomal DNA sequences of this species were not yet reported. Multiple gene phylogenic analyses suggested that this isolate clustered at the base of the Dipodascaceae (Saccharomycetales, Saccharomycetes, and Ascomycota). JEY63 was named Candida tunisiensis sp. nov. according to several phenotypic criteria and its geographical origin. C. tunisiensis was able to grow at 42°C and does not form chlamydospores and hyphae but could grow as yeast and pseudohyphal forms. C. tunisiensis exhibited most probably a haploid genome with an estimated size of 10 Mb on at least three chromosomes. Using European Committee for Antimicrobial Susceptibility Testing (EUCAST) and Clinical and Laboratory Standards Institute (CLSI) Candida albicans susceptibility breakpoints as a reference, C. tunisiensis was resistant to fluconazole (MIC = 8 μg/ml), voriconazole (MIC = 0.5 μg/ml), itraconazole (MIC = 16 μg/ml), and amphotericin B (MIC = 4 μg/ml) but still susceptible to posaconazole (MIC = 0.008 μg/ml) and caspofungin (MIC = 0.5 μg/ml). In conclusion, MALDI-TOF MS permitted the early selection of an unusual isolate, which was still unreported in molecular databases but could not be unambiguously classified based on phylogenetic approaches.