Dissertations / Theses: 'OMPs'

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Wang, Yi. "Geos-chem adjoint inversion of SO2 and NOx emissions with multi-sensor (OMPS, OMI, and VIIRS) data over China." Diss., University of Iowa, 2019. https://ir.uiowa.edu/etd/7042.

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Accurate and timely SO2 and NOx emission inventories are required to simulate and forecast SO2 and NO2 concentrations in the atmosphere. However, bottom-up emission inventories have a time lag of at least one year, as it takes time to collect necessary activity rates and emission factors. This thesis focuses on using satellite data from Ozone Monitoring Instrument (OMI), Ozone Mapper and Profile Suite (OMPS), and Visible Infrared Imaging Radiometer Suite (VIIRS) to optimize SO2 and NOx emissions through the GEOS-Chem adjoint model. The optimized emission inventories are further applied to improve air quality simulation and forecasts. We firstly integrate OMI SO2 satellite measurements and GEOS-Chem adjoint model simulations to constrain monthly anthropogenic SO2 emissions. The effectiveness of this approach is demonstrated for 14 months over China; resultant posterior emissions not only capture a 20% SO2 emission reduction in Beijing during the 2008 Olympic Games but also improve agreement between modeled and in situ surface measurements. Further analysis reveals that posterior emissions estimates, compared to the prior, lead to significant improvements in forecasting monthly surface and columnar SO2. SO2 and NO2 observations from the newer sensor OMPS are used to optimize SO2 and NOx emissions over China for October 2013 through GEOS-Chem adjoint model. OMPS SO2 and NO2 observations are assimilated separately to optimize corresponding emissions, respectively, and posterior emissions, compared to the prior, yield improvements in simulating columnar SO2 and NO2, which are validated with both OMI and OMPS observations. The posterior emissions from assimilating OMPS SO2 and NO2 simultaneously are within -3% to 15% of separate assimilations for SO2 emissions and ±1% for NOx, and the joint assimilation saves about 50% computational time. Changes of NH3 emissions modify NO2 lifetime, hence affecting posterior NOx emissions in separate assimilations, and having impacts on both posterior SO2 and NOx emissions in joint assimilation. All these assimilation experiments are conducted at coarse (2°×2.5°) spatial resolution to save computational time, but coarse-resolution simulations underestimate hot spots of surface SO2 and NO2. Thus, the posterior coarse-resolution emissions are further efficiently downscaled to fine resolution (0.25°×0.3125°) according to spatial distributions of prior MIX emissions or VIIRS nighttime lights. Posterior fine-resolution simulation and forecasts, validating with in situ surface SO2 and NO2 measurements, improve on the prior ones.

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Yang, Yiying. "Mécanismes de biogenèse et de maintien de la membrane externe des bactéries à Gram négatif." Thesis, Toulouse 3, 2021. http://www.theses.fr/2021TOU30279.

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Les bactéries à Gram négatif comprennent un certain nombre d'agents pathogènes animaux redoutables qui sont particulièrement résistants aux thérapies antibiotiques grâce à la fonction protectrice de leur enveloppe bactérienne. L'enveloppe des bactéries à Gram négatif est composée d'une membrane interne (MI) et d'une membrane externe (ME), séparées par un espace, le périplasme, contenant le peptidoglycane (PG). Le feuillet externe de la bicouche de la ME contient des lipopolysaccharides (LPS) qui forment une barrière imperméable à certaines molécules toxiques, tels que les détergents ou des petites molécules hydrophobes. Les nutriments sont transportés par les protéines (OMP) de la ME. D'autres OMP remplissent des fonctions de biogenèse de l'enveloppe, notamment l'assemblage des OMP et des LPS. Les OMP sont assemblées dans la ME par le complexe d'assemblage en tonneau bêta (BAM), un hétéro-pentamère contenant l'OMP essentielle BamA et quatre lipoprotéines BamBCDE. L'assemblage du LPS nécessite une autre OMP essentielle, LptD, qui s'associe de manière stable avec la lipoprotéine LptE. Un assemblage défectueux des OMP provoque un stress de l'enveloppe et rend les bactéries Gram-négatives sensibles aux antibiotiques et aux détergents. Le complexe BAM représente donc une cible prometteuse pour le développement de nouveaux antibiotiques. La fonction moléculaire du complexe BAM dans la biogénèse des ME est mal comprise. En utilisant une stratégie de spectrométrie de masse quantitative, le laboratoire d'accueil a récemment identifié deux nouveaux interacteurs putatifs du complexe BAM, les lipoprotéines DolP (anciennement YraP) et YifL, toutes deux de fonctions inconnues. L'objectif de ce travail de thèse était de caractériser les rôles respectifs de DolP et YifL au sein du complexe BAM. DolP est une lipoprotéine de la ME de 20 kDa. L’accumulation d’OMP mal repliées dans le périplasme induit un stress de l’enveloppe qui, à son tour, stimule la production à la fois de BamA et de DolP. Cependant, le rôle de cette dernière dans la biogenèse des OMP n’est pas connu. Dans cette étude, en utilisant un crible génétique, nous avons montré que DolP est critique pour la croissance des cellules qui subissent un stress d'enveloppe. Nous avons montré que l’accumulation de BamA dans la ME est toxique pour les cellules mais que DolP est capable de contrecarrer cette toxicité en favorisant le bon repliement de BamA (Ranavaco-first; Yangco-first; Orenday-Tapiaco-first, et al., 2021). En parallèle, la caractérisation de l'interaction BAM-YifL a permis de montrer que YifL interagit avec BamA et BamD. De manière intéressante, nous avons découvert que YifL interagit également avec la machinerie de sécrétion des LPS, LptDE, qui est assemblée par le complexe BAM dans la ME. Ce processus nécessite également la machinerie de repliement oxydatif DsbA pour oxyder les 4 résidus de cystéine dans LptD de façon séquentielle. Une analyse génétique a montré que la délétion de yifL exacerbe la sensibilité des cellules bamB ou dsbA au SDS, un détergent normalement exclu par la couche de LPS. Nous avons constaté qu'en l'absence de YifL, LptD se fixe transitoirement au complexe BAM sous une forme intermédiaire partiellement oxydée. L'oxydation efficace de LptD pour former une protéine mature et fonctionnelle nécessite YifL. Nos résultats révèlent pour la première fois que YifL est critique pour la biogenèse efficace du complexe LptDE
Gram-negative bacteria include a number of dreadful animal pathogens that are particularly resistant to antibiotic therapies thanks to the sheltering function of their bacterial envelope. The envelope is composed of an inner and an outer membrane (IM and OM), and the separating periplasm containing the peptidoglycan (PG). The outer leaflet of the OM bilayer largely consists of lipopolysaccharide (LPS) that forms a permeability barrier against toxic molecules, including detergents and small hydrophobic molecules. Nutrients are transported via OM-spanning proteins (OMPs). Other OMPs perform envelope biogenesis functions, including the assembly of OMPs and LPS. OMPs are assembled into the OM by the beta-barrel assembly machinery (BAM), a heteropentamer containing the essential OMP BamA and four lipoproteins BamBCDE. The assembly of LPS requires another essential OMP, LptD, which stably associates with the lipoprotein LptE. Defective assembly of OMPs causes envelope stress and renders Gram-negative bacteria sensitive to antibiotics and detergents. Hence, the BAM complex represents a promising target for the development of new therapies. The mechanistic details of how the BAM complex functions ensuring efficient OM biogenesis are only marginally understood. By using a quantitative mass-spectrometry strategy the hosting lab has recently identified two novel putative interactors of the BAM complex of Escherichia coli, the lipoproteins DolP (formerly YraP) and YifL, both of unknown functions. The aim of this PhD thesis work was to characterize the roles of DolP and YifL at the BAM complex. DolP is a ~20 kDa OM lipoprotein that localizes in the periphery of E. coli cells and accumulates at the mid-cell specifically during a late step of cell division. DolP is upregulated during envelope stress caused by the accumulation of unfolded OMPs in the periplasm. Whether DolP plays any role in OMP biogenesis, however, was unknown. In this study, by using a genetic screen, we have shown that DolP is critical for the fitness of cells that undergo envelope stress. We have demonstrated that an increment of BamA in the OM, which is also upregulated during envelope stress, is potentially toxic for the cells. We provide evidence that DolP promotes proper folding and function of BamA thereby counteracting its toxicity. The mid-cell recruitment of DolP had been linked to regulation of septal peptidoglycan hydrolysis by an unknown mechanism. Our study reveals that during envelope stress DolP loses its association with the mid-cell, thus revealing a mechanistic link between impaired OMP biogenesis and a late step of cell division (Ranavaco-first; Yangco-first; Orenday-Tapiaco-first, et al., 2021). Next the BAM-YifL interaction was characterized. We showed that the ~7 kDa YifL interacts with BamA and BamD. Interestingly, we have found that YifL also interacts with the LPS secretory machinery LptDE, which is assembled by the BAM complex into the OM

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Pezeshki, Soroosh [Verfasser]. "Simulation of Transport through OmpF and OmpC Channels / Soroosh Pezeshki." Bremen : IRC-Library, Information Resource Center der Jacobs University Bremen, 2010. http://d-nb.info/1034994654/34.

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Pathania, Monisha. "Characterisation of the major porins OmpU and OmpT of Vibrio cholerae." Thesis, University of Newcastle upon Tyne, 2018. http://hdl.handle.net/10443/4181.

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The asymmetric outer membrane (OM) of a Gram-negative bacterium has many proteins embedded as β-barrel structures in it called outer membrane proteins (OMPs). The majority of these OMPs (porins) form non-selective channels across the OM to allow passive uptake of substrates. The treatment for infections caused by such bacteria mostly involves the administration of drugs/antibiotics, for which these porins play a very crucial role by providing an efficient (although not yet fully understood) route through their channel. The goal of this study is to study small-molecule permeation through the major porins, OmpU and OmpT, of Vibrio cholerae (the causative agent of cholera) for potential use of these proteins as the target for designing antibiotics or vaccines. Towards this project, we have succeeded in solving the 3D X-ray crystal structures of OmpU and OmpT as well as the structures of the major porins from Klebsiella pneumoniae (OmpK36) and Enterobacter cloacae (OmpE36, OmpE35). The proteins (OmpU/T, OmpE35/E36 and OmpK36) show the typical arrangement of porins with three β-barrel monomers arranged into a trimer. Each monomer displays 16 antiparallel β-strands forming the hollow β-barrel formed by 8 long extracellular loops and 8 short periplasmic turns. The latching loop L2 stabilises the trimer while loop L3 departs from the β-barrel fold and constricts the pore half-way through the channel. An unusual feature is observed in the channels of OmpU and OmpT that distinguishes them from other typical porins. In OmpU, the first 10 residues of N-terminus insert into the barrel and constrict the pore. In contrast, the structure of OmpT reveals that the extracellular loop L8 folds inwards to constrict the lumen of the channel. Such constriction elements not only reduce the pore sizes of OmpU and OmpT but may also dramatically affect the internal electrostatics of these channels, which is very important for small-molecule permeation. In addition, we also performed single channel electrophysiology experiments with OmpU and OmpT which revealed interesting features with the addition of carbapenems.

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Moya, Torres Aniel. "The role of Serratia marcescens OmpF and OmpC porins in antibiotic resistance and virulence." Microbiology, 2014. http://hdl.handle.net/1993/30388.

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Serratia marcescens is a microorganism that constitutes one of the primary causes of nosocomial outbreaks in hospitals. One characteristic of S. marcescens clinical isolates is the high resistance to antimicrobials used in the clinic. Recent reports have attributed antibiotic resistance to altered porin expression. In this study, S. marcescens Db11 isogenic porin mutants were generated using the generalized transducing phage IF3 to move marked target-genes between isogenic strain backgrounds, prior to removal of the antibiotic resistance cassette by Flp-FRT strategy. Mutants for three classical porins were obtained and the effect of ompF and ompC deletion on antimicrobial resistance was evaluated by MIC. The use of this method avoided the incorporation of additional resistance markers and is an alternative strategy to create clean unmarked Serratia mutant strains. The lack of OmpF, but not OmpC, significantly increased MIC values to the β-lactam drugs such as ampicillin and cefoxitin as well as to nitrofurantoin. Genetic deletion of both ompF and ompC did not compromise the integrity of the bacterial cell envelope in optimal growth conditions, suggesting that other outer-membrane porins may function in a compensatory role to facilitate nutrient uptake and cell envelope integrity. S. marcescens is a pathogen of C. elegans and can be used to study host response to bacterial infections. The host model Caenorhabditis elegans was used in this study to investigate if porin deficits affected bacterial virulence. When porin mutants were evaluated in the C. elegans host model, the virulence of the single porin mutant strains increased in comparison to the wild-type. This study demonstrated that mutations of ompF and ompC did not attenuate S. marcescens virulence, but rather demonstrated a hypervirulent phenotype when they were assessed in C. elegans. The absence of OmpF and OmpC porins in S. marcescens appeared to increase the bacterial invasion of C. elegans nematode tissue. Further studies are required to fully investigate the hypervirulent phenotype of these mutant strains. This study reveals that decrease of outer membrane permeability due to porin mutation alters antimicrobial resistance and does not generate virulence attenuation in S. marcescens Db11.
May 2015

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Aguilar, Mónica Alejandra Pavez. "Caracterização molecular da resistência aos carbapenêmicos em enterobactérias isoladas em hospitais brasileiros." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/9/9136/tde-28092009-144325/.

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Introdução: Após o surgimento e disseminação das β-lactamases (BL) de amplo espectro em membros da família Enterobacteriaceae, os antibióticos carbapenêmicos (imipenem, meropenem, ertapenem) têm sido considerados a terapia de escolha pela estabilidade apresentada contra estas enzimas. Infelizmente, em 2005, o primeiro caso de infecção fatal por um isolado de Klebsiella pneumoniae resistente aos carbapenêmicos foi relatado em nosso país. A partir deste, novos casos de infecção, inclusive por outros gêneros da família Enterobacteriaceae como Enterobacter, Providencia e Escherichia, começaram a surgir. Como mecanismo de resistência aos carbapenêmicos, a expressão de enzimas carbapenemases tem sido mundialmente relatada, enquanto que, a impermeabilidade associada à produção de enzimas do tipo AmpC ou ESBL tem sido esporádica. Com relação à mobilização dos determinantes genéticos de resistência, elementos móveis como integrons e plasmídios têm sido associados. O presente trabalho teve como objetivo caracterizar os mecanismos de resistência aos carbapenêmicos, sua mobilização genética e disseminação clonal em amostras clínicas de enterobactérias isoladas em diversos hospitais brasileiros. Material e métodos: Foram estudadas 28 cepas recuperadas de oito centros hospitalares descritas como resistentes ao imipenem. A caracterização fenotípica foi realizada por: i) determinação da CIM na presença e ausência de inibidores de BL, ii) bioensaio para produção de BL e iii) SDS-PAGE para investigar a ausência de porinas. A confirmação genotípica da resistência mediada por β-lactamases foi realizada por PCR e seqüenciamento e a sua localização plasmidial foi estudada por transformação. Por último, a tipagem molecular foi realizada pela técnica de ERIC-PCR, sendo confirmada pela técnica de PFGE. Resultados: 25 cepas apresentaram resistência para carbapenêmicos (imipenem MIC 8-128 µg/mL), todas com perfil de multiresistência incluindo cefoxitina (CIM90 ≥32 µg/mL). Foram identificados três determinantes de resistência, entre eles, a produção de carbapenemases de tipo MBL (IMP-1) e a enzima KPC-2, recentemente descrita, sendo emergente no país. O mecanismo mais prevalente nas amostras estudadas foi a impermeabilidade de membrana associada à expressão de enzimas do tipo AmpC (CMY-2 plasmidial para E. coli e AmpC cromossômica no caso de Enterobacter aerogenes), as quais mostraram uma contribuição significativa para a resistência aos carbapenêmicos. Dos 28 isolados, 18 apresentaram a perda da porina de 36 kDa, responsável pela entrada de antimicrobianos na bactéria, como os carbapenêmicos. Tanto os genes blaKPC-2 e blaCMY-2 foram transferidos com êxito para E. coli DH10B, confirmando sua localização plasmidial. A co-produção de carbapenemase ou enzimas do tipo AmpC com ESBL do tipo CTX-M foi confirmada em 68% dos isolados. A tipagem molecular mostrou uma disseminação clonal para os isolados carregando determinantes IMP-1 e as enzimas do tipo AmpC cromossômica e plasmidial. Ao contrário, isolados expressando KPC não foram clonalmente relacionadas. Conclusão: A caracterização de resistência apresentada neste trabalho demonstrou uma mudança no perfil de resistência da família Enterobactériaceae devido à sua versatilidade para a aquisição de novos mecanismos de resistência, como sua adaptação aos ambientes hostis. A perda da porina foi o mecanismo mais freqüente nesta família e a co-produção de BL foi um evento associado. Finalmente, os dados obtidos na tipagem molecular denotaram uma disseminação majoritariamente clonal na cidade de São Paulo, com exceção das cepas produtoras de KPC-2, cuja presença tem sido relatada em outras cidades do país, sugerindo a participação de uma transferência horizontal.
Introduction: After emergence, and dissemination of extended spectrum β-lactamases (ESBL) in members of the Enterobacteriaceae family, carbapenem antibiotics (imipenem, meropenem, ertapenem) have been the therapy of choice, since they are stable to ESBL hydrolysis. Unfortunately, in 2005, the first fatal case of infection by carbapenem-resistant Klebsiella pneumoniae was related in our country. From this episode, new infection cases, including by other genders of Enterobacteriaceae such as Enterobacter, Providencia and Escherichia, began to appear. Regarding carbapenem resistance mechanisms, expression of carbapenem hydrolyzing enzymes has been worldwide reported, whereas interplay between impermeability and AmpC or ESBL production has been sporadic. Furthermore, integrons and plasmids have been associated with mobilization of genetic determinants. The aim of this study was to characterize the mechanisms of resistance to carbapenems, their genetic mobilization and clonal dissemination in enterobacterial isolates recovered from clinical samples in Brazilian hospitals. Material and methods: 28 imipenem-resistant isolates recovered from 8 hospital centres were studied. Phenotypic profiles were characterized by: i) MIC of carbapenems in the presence/absence of β-lactamase inhibitors; ii) bioassay for β-lactamase production; iii) SDS-PAGE to investigate absence of outer membrane porins (OMPs). Molecular characterization of β-lactamase-mediated resistance was made by PCR and DNA sequencing and their plasmid localization was evaluated by transformation. Finally, epidemiological typing was performed by ERIC-PCR, being confirmed by PFGE. Results: 25 isolates were confirmed as being resistant to imipenem (MIC 8-128 µg/mL), exhibiting a multidrug-resistant profile, including to cefoxitin (MIC90 ≥32 µg/mL). Two main mechanism of resistance were identified: i) hydrolysis of carbapenem by class B (IMP-1-like MBL) and class A (KPC-2) enzymes, (the latter being recently reported in our country), and ii) outer membrane impermeability associated to AmpC enzyme production (plasmid-mediated CMY-2 for E. coli and chromosomal AmpC for E. aerogenes), which was the most prevalent mechanism found. Eighteen of 28 isolates lacked 36kDa OMP, which is responsible for uptake of carbapenem antibiotics. The blaKPC-2 and blaCMY-2 genes were successful transferred to E. coli DH10B, confirming the plasmid location of both genes. Co-production of carbapenemases or AmpC and CTXM enzymes was confirmed in 68% of isolates, and molecular typing showed clonal dissemination of IMP-1-, plasmid AmpC- and chromosomal AmpC-producing isolates. Otherwise, KPC-2-producing isolates were not clonally related. Conclusion: The characterization of resistance mechanisms to carbapenems, in this study, reveals a change in the resistance patterns among Enterobacteriaceae family members in Brazilian hospitals, due to versatility of isolates to acquire new resistance determinants, which it has favoured the adaptation to hostile environments. Lack of 36 kDa OMP was the most frequent resistance mechanism, being associated to co-production of β-lactamases. Finally, molecular typing denote a clonal dissemination of imipenem-resistant isolates in Sao Paulo city, with exception of KPC-2-producing isolates, which have been described in other Brazilian cities, suggesting a horizontal gene transfer.

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Arosio, Carlo [Verfasser], John P. [Akademischer Betreuer] Burrows, John P. [Gutachter] Burrows, and Erkki [Gutachter] Kyrölä. "Retrieval of ozone profiles from OMPS-LP observations and merging with SCIAMACHY and SAGE II time series to study long-term changes / Carlo Arosio ; Gutachter: John P. Burrows, Erkki Kyrölä ; Betreuer: John P. Burrows." Bremen : Staats- und Universitätsbibliothek Bremen, 2019. http://d-nb.info/1192909860/34.

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Dumetz, Fabien. "Les antigènes de surface de Flavobacterium psychrophilum : approche protéomique et caractérisation de deux protéines (OmpA/P60 et OmpH/P18)." Bordeaux 2, 2006. http://www.theses.fr/2006BOR21363.

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Flavobacterium est une bactérie Gram négative pathogène de poissons. Par une approche protéomique, nous avons pu identifier certains composants de la membrane externe : des adhésines putatives, des protéines impliquées dans l'acquisition du fer ou dans les systèmes d'efflux, une HtrA homologue et plusieurs molécules de fonctions inconnues. L'analyse de la membrane externe a révélé plusieurs antigènes protéiques majoritaires dont OmpA/P60. La susceptibilité des deux protéines aux traitements in situ des cellules avec de la protéinase K et la mise en évidence d'effets bactériostatiques/bactéricides d'anticorps spécifiques indiquent sans ambiguité l'exposition en surface de ces deux molécules. Des essais de vaccination ont montré que ces deux protéines pouvaient induire un fort taux d'anticorps protecteurs. Ces résultats indiquent qu'OmpA/P60 et OmpH/P18 sont des candidats prometteurs pour le développement de futurs vaccins
Flavobacterium psychrophilum is a Gram negative bacteria responsible for fish infection. We used a proteomic approach to identify some outer membrane components such as putative adhesins, proteins involved in iron acquisition or in efflux systems, a HtrA homologue and some other molecules with unknown function. Several major antigens have been identified in the outer membrane including the two components OmpH/P18 and OmpA/P60. They are surface-exposed since they were completely digested by in situ proteinase K treatment and the two monospecific sera were bacteriostatic/bactericidal. Vaccination trials showed that both proteins can induce a high titter of specific antibodies which are protective. Collectively, these results indicate that these two proteins could be used in future vaccine development as promising candidate antigens

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Al-Akash, Ahmed M. "Increased expression of ompA, ompX, dedA, and gutS genes in Enterobacter sp. YSU in the presence of selenite." Youngstown State University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1607517925584702.

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Subotic, Vladimir. "Evaluating techniques for parallelization tuning in MPI, OmpSs and MPI/OmpSs." Doctoral thesis, Universitat Politècnica de Catalunya, 2013. http://hdl.handle.net/10803/129573.

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Parallel programming is used to partition a computational problem among multiple processing units and to define how they interact (communicate and synchronize) in order to guarantee the correct result. The performance that is achieved when executing the parallel program on a parallel architecture is usually far from the optimal: computation unbalance and excessive interaction among processing units often cause lost cycles, reducing the efficiency of parallel computation. In this thesis we propose techniques oriented to better exploit parallelism in parallel applications, with emphasis in techniques that increase asynchronism. Theoretically, this type of parallelization tuning promises multiple benefits. First, it should mitigate communication and synchronization delays, thus increasing the overall performance. Furthermore, parallelization tuning should expose additional parallelism and therefore increase the scalability of execution. Finally, increased asynchronism would provide higher tolerance to slower networks and external noise. In the first part of this thesis, we study the potential for tuning MPI parallelism. More specifically, we explore automatic techniques to overlap communication and computation. We propose a speculative messaging technique that increases the overlap and requires no changes of the original MPI application. Our technique automatically identifies the application’s MPI activity and reinterprets that activity using optimally placed non-blocking MPI requests. We demonstrate that this overlapping technique increases the asynchronism of MPI messages, maximizing the overlap, and consequently leading to execution speedup and higher tolerance to bandwidth reduction. However, in the case of realistic scientific workloads, we show that the overlapping potential is significantly limited by the pattern by which each MPI process locally operates on MPI messages. In the second part of this thesis, we study the potential for tuning hybrid MPI/OmpSs parallelism. We try to gain a better understanding of the parallelism of hybrid MPI/OmpSs applications in order to evaluate how these applications would execute on future machines and to predict the execution bottlenecks that are likely to emerge. We explore how MPI/OmpSs applications could scale on the parallel machine with hundreds of cores per node. Furthermore, we investigate how this high parallelism within each node would reflect on the network constraints. We especially focus on identifying critical code sections in MPI/OmpSs. We devised a technique that quickly evaluates, for a given MPI/OmpSs application and the selected target machine, which code section should be optimized in order to gain the highest performance benefits. Also, this thesis studies techniques to quickly explore the potential OmpSs parallelism inherent in applications. We provide mechanisms to easily evaluate potential parallelism of any task decomposition. Furthermore, we describe an iterative trialand-error approach to search for a task decomposition that will expose sufficient parallelism for a given target machine. Finally, we explore potential of automating the iterative approach by capturing the programmers’ experience into an expert system that can autonomously lead the search process. Also, throughout the work on this thesis, we designed development tools that can be useful to other researchers in the field. The most advanced of these tools is Tareador – a tool to help porting MPI applications to MPI/OmpSs programming model. Tareador provides a simple interface to propose some decomposition of a code into OmpSs tasks. Tareador dynamically calculates data dependencies among the annotated tasks, and automatically estimates the potential OmpSs parallelization. Furthermore, Tareador gives additional hints on how to complete the process of porting the application to OmpSs. Tareador already proved itself useful, by being included in the academic classes on parallel programming at UPC.
La programación paralela consiste en dividir un problema de computación entre múltiples unidades de procesamiento y definir como interactúan (comunicación y sincronización) para garantizar un resultado correcto. El rendimiento de un programa paralelo normalmente está muy lejos de ser óptimo: el desequilibrio de la carga computacional y la excesiva interacción entre las unidades de procesamiento a menudo causa ciclos perdidos, reduciendo la eficiencia de la computación paralela. En esta tesis proponemos técnicas orientadas a explotar mejor el paralelismo en aplicaciones paralelas, poniendo énfasis en técnicas que incrementan el asincronismo. En teoría, estas técnicas prometen múltiples beneficios. Primero, tendrían que mitigar el retraso de la comunicación y la sincronización, y por lo tanto incrementar el rendimiento global. Además, la calibración de la paralelización tendría que exponer un paralelismo adicional, incrementando la escalabilidad de la ejecución. Finalmente, un incremente en el asincronismo proveería una tolerancia mayor a redes de comunicación lentas y ruido externo. En la primera parte de la tesis, estudiamos el potencial para la calibración del paralelismo a través de MPI. En concreto, exploramos técnicas automáticas para solapar la comunicación con la computación. Proponemos una técnica de mensajería especulativa que incrementa el solapamiento y no requiere cambios en la aplicación MPI original. Nuestra técnica identifica automáticamente la actividad MPI de la aplicación y la reinterpreta usando solicitudes MPI no bloqueantes situadas óptimamente. Demostramos que esta técnica maximiza el solapamiento y, en consecuencia, acelera la ejecución y permite una mayor tolerancia a las reducciones de ancho de banda. Aún así, en el caso de cargas de trabajo científico realistas, mostramos que el potencial de solapamiento está significativamente limitado por el patrón según el cual cada proceso MPI opera localmente en el paso de mensajes. En la segunda parte de esta tesis, exploramos el potencial para calibrar el paralelismo híbrido MPI/OmpSs. Intentamos obtener una comprensión mejor del paralelismo de aplicaciones híbridas MPI/OmpSs para evaluar de qué manera se ejecutarían en futuras máquinas. Exploramos como las aplicaciones MPI/OmpSs pueden escalar en una máquina paralela con centenares de núcleos por nodo. Además, investigamos cómo este paralelismo de cada nodo se reflejaría en las restricciones de la red de comunicación. En especia, nos concentramos en identificar secciones críticas de código en MPI/OmpSs. Hemos concebido una técnica que rápidamente evalúa, para una aplicación MPI/OmpSs dada y la máquina objetivo seleccionada, qué sección de código tendría que ser optimizada para obtener la mayor ganancia de rendimiento. También estudiamos técnicas para explorar rápidamente el paralelismo potencial de OmpSs inherente en las aplicaciones. Proporcionamos mecanismos para evaluar fácilmente el paralelismo potencial de cualquier descomposición en tareas. Además, describimos una aproximación iterativa para buscar una descomposición en tareas que mostrará el suficiente paralelismo en la máquina objetivo dada. Para finalizar, exploramos el potencial para automatizar la aproximación iterativa. En el trabajo expuesto en esta tesis hemos diseñado herramientas que pueden ser útiles para otros investigadores de este campo. La más avanzada es Tareador, una herramienta para ayudar a migrar aplicaciones al modelo de programación MPI/OmpSs. Tareador proporciona una interfaz simple para proponer una descomposición del código en tareas OmpSs. Tareador también calcula dinámicamente las dependencias de datos entre las tareas anotadas, y automáticamente estima el potencial de paralelización OmpSs. Por último, Tareador da indicaciones adicionales sobre como completar el proceso de migración a OmpSs. Tareador ya se ha mostrado útil al ser incluido en las clases de programación de la UPC.

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11

Marjanović, Vladimir. "The MPI/OmpSs parallel programming model." Doctoral thesis, Universitat Politècnica de Catalunya, 2016. http://hdl.handle.net/10803/398135.

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Even today supercomputing systems have already reached millions of cores for a single machine, which are connected by using a complex network interconnection. Reducing communication time across processes becomes the most important issue in order to achieve the highest possible performance. The Message Passing Interface (MPI), which is the most widely used programming model for large distributed memory, supports asynchronous communication primitives for overlapping communication and computation. However, these primitives are difficult to use and increase code complexity. which then requiring more development effort and making less readable programs. This thesis presents a new programming model, which allows the programmer to easily introduce the asynchrony necessary to overlap communication and computation. The proposed programming model is based on MPI and tasked based shared memory framework, namely OmpSs. The thesis further describes implementation details which in order to allow efficient inter-operation of the OmpSs runtime and MPI. The thesis demonstrates the hybrid use of MPI/OmpSs with several applications of which the HPL benchmark is the most important case study. The hybrid MPI/OmpSs versions significantly improve the performance of the applications compared with their pure MPI counterparts. For the HPL we get close to the asymptotic performance at relatively small problem sizes and still get significant benefits at large problem sizes. In addition, the hybrid MPI/OmpSs approach substantially reduces code complexity and is less sensitive to network bandwidth and operating system noise than the pure MPI versions. In addition, the thesis analyzes and compares current techniques for overlapping computation and collective communication, including approaches using point-to-point communications and additional communication threads, respectively. The thesis stresses the importance of understanding the characteristic of a computational kernel that runs concurrently with communication. Experimental evaluations is done using the Communication Computation Concurrent (CCUBE) synthetic benchmark, developed in this thesis, as well as the HPL.
Las supercomputadoras están formadas por un creciente número de núcleos, del orden de millones en la actualidad, que se comunican a través de una compleja red de interconexión. Para obtener el más alto rendimiento posible es necesario reducir el tiempo de comunicación entre procesos. MPI ("Message Passing Interface", Interfaz de Paso de Mensajes), el modelo de programación más usado para grandes sistemas con memoria distribuida, permite llamadas de comunicación asíncrona para solapar la comunicación y la computación. Sin embargo, dichas llamadas son difíciles de usar e incrementan la complejidad del código, necesitándose un mayor esfuerzo en la implementación del código y dando lugar a programas más difíciles de leer. Esta tesis presenta un nuevo modelo de programación que permite al programador introducir fácilmente la asincronía necesaria para solapar la comunicación y la computación. El modelo de programación propuesto está fundamentado en MPI y la infraestructura basada en tareas y memoria compartida OmpSs. La tesis describe en profundidad los detalles de la implementación para la eficiente interoperabilidad entre OmpSs y MPI. En la tesis se demuestra el uso híbrido de MPI/OmpSs con distintas aplicaciones de las cuales el benchmark HPL es el más importante. La versión híbrida MPI/OmpSs mejora significativamente el rendimiento de las aplicaciones respecto a las versiones MPI originales. En el caso de HPL se acerca a un rendimiento asintótico para problemas relativamente pequeños, obteniendo mejoras significativas para problemas grandes. Además la versión híbrida MPI/OmpSs reduce substancialmente la complejidad del código y se ve menos afectada por el ancho de banda de la red y el ruido del sistema operativo que la versión MPI pura. Esta tesis también analiza y compara otros métodos actuales para solapar computación y comunicación colectiva, tales como usar comunicación punto a punto con hilos adicionales para la comunicación. La tesis resalta la importancia de entender las características de la computación que se ejecuta simultáneamente con la comunicación. Los resultados experimentales se han obtenido usando el benchmark sintético CCUBE ("Communication Computation Concurrent", Comunicación Computación Concurrente), desarrollado en esta tesis, además de HPL.

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Martinsen, Thomas Bølstad. "Energy Efficient Task Pool Scheduler in OmpSs." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for datateknikk og informasjonsvitenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-22976.

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The European Mont-Blanc project aims to build future exascale systems using energy efficient low-power devices. Exascale systems built using low-power devices will require a large number of processors to achieve competitive performance against state-of-the-art supercomputers. The project relies on the OmpSs programming model and its runtime system, in order to handle the complexity of such a massively parallel system.In this study, an alternative scheduling-plugin has been developed to improve the energy efficiency of the OmpSs runtime system. The proposed scheduling policy from the paper 'Process Cruise Control' has been extended for multi-core systems and integrated into the developed scheduling-plugin. The scheduling-plugin improves the energy efficiency by continuously monitoring the workload, in order to identify situations where it would be beneficial to adjust the frequency through dynamic voltage and frequency scaling. The solution has been evaluated on Sandy Bridge-EP with 17 OmpSs application kernels. Energy consumption is measured for the processor package through the Running Average Power Limit interface on Sandy Bridge. The results shows that energy savings can reach up to 30% in memory intensive applications with limited impact on performance.

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Sener, Johnny, and Anders Svensson. "Effektiv prissättning av OMXS-optioner : En empirisk undersökning." Thesis, Uppsala University, Department of Economics, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7030.

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I uppsatsen har vi undersökt köpoptioner med OMXS30 som underliggande, syftet var att se om det fanns möjligheter till att göra arbitrage. Detta innebär att de är felprissatta. Vi har i vår undersökning testat optioners nedre gräns och köp-sälj paritetsvillkoret. Resultaten tyder på att det finns ett antal tillfällen då marknaden inte är effektiv, antalet tillfällen skiljer sig åt under olika marknadsförhållanden. De slutsatser vi kan dra är att marknaden måste vara mogen och marknadens aktörer måste ha en tydlig bild om i vilken riktning marknaden är på väg för att vi ska kunna säga att optionspriserna är effektivt prissatta. När investerare agerar irrationellt och osäkerheten är hög ökar frekvensen av antalet felprissättningar på finansiella instrument, däribland optioner.

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Baboolal, Thomas. "Analysis of the colocin N/OmpF translocation complex." Thesis, University of Newcastle Upon Tyne, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.420020.

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El, Kouhen Rachid. "Colicine N et porine OmpF, un dialogue dynamique." Aix-Marseille 1, 1995. http://www.theses.fr/1995AIX11035.

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La colicine n, bacteriocine produite par e. Coli, est active sur des souches apparentees. Son mode d'action comprend trois etapes: (i) fixation sur la porine ompf a la surface bacterienne, (ii) utilisation de cette meme porine et des proteines tolaq pour traverser la membrane externe (iii) formation de pores voltage-dependant dans la membrane interne. La colicine n (42kda) est organisee en domaines structuraux, chacun etant associe a une etape du mode d'action. Le domaine central r (67-182) est responsable de la fixation sur ompf. Le domaine n-terminal t, est implique dans la translocation a travers la membrane externe ; il peut etre subdivise en deux sous-domaines t1 et t2. Le site recepteur de la colicine n est conserve sur le trimere ompf purifie. L'interaction colicine n-ompf depend de la presence du domaine r. Le trimere purifie est capable de proteger les cellules sensibles contre l'action des colicines a et n. Le niveau de protection depend de l'etat conformationnel de la porine. Cette association recepteur-ligand a la surface bacterienne est visualisee en microscopie electronique. La cinetique de fixation de la colicine n est tres rapide. L'etude de la translocation montre l'existence de deux populations de colicine n: une, correspondant aux colicines internalisees et une autre, accessible a la surface cellulaire, degradee par les differentes enzymes. 10(#1) secondes est le temps qui separe l'addition de la colicine n et de la formation du pore au niveau de la membrane interne. La vitesse maximale d'efflux de k#+ intracellulaire est obtenue a une multiplicite de 300-400: correspond aux colicines protegees

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Fourel, Didier. "La porine OmpF d'Escherichia Coli : assemblage et fonctions." Aix-Marseille 3, 1992. http://www.theses.fr/1992AIX30028.

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La membrane externe des bacteries a gram negatif protege la cellule des agressions de l'environnement. Elle est constituee de lipides et de proteines. Les porines representent une classe majeure des proteines de l'enveloppe bacterienne, leur role etant d'assurer le passage des nutriments vers l'interieur de la cellule. A l'aide de sondes immunologiques, nous avons etudie l'assemblage de la porine ompf qui est synthetisee dans le cytoplasme sous forme d'un precurseur. Le peptide signal est ensuite clive et le monomere libere est tres rapidement insere dans la membrane externe sous forme d'un trimere etroitement associe au lipopolysaccharide. Au cours de ce phenomene, une etape intermediaire fait intervenir un trimere transitoire instable. A l'aide de proteines hybrides et de mutants ponctuels obtenus par mutagenese chimique, nous nous sommes interesses a la fonction recepteur de ompf. La porine est utilisee par des toxines bacteriennes, les colicines a et n, comme point d'entree dans la cellule. Les regions et acides amines participant au site recepteur ont ete definis. Avec les memes outils, nous avons aborde la topologie de la porine dans la membrane, determine les sites et acides amines participant aux epitopes, ainsi que les regions impliquees au cours de l'assemblage. Nous avons, par consequent, defini le role de regions impliquees dans l'assemblage et la fonction de la porine ompf

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Diamond, Cornelius. "OMOS : optically written micro-optical systems in photopolymer /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC IP addresses, 2000. http://wwwlib.umi.com/cr/ucsd/fullcit?p9963665.

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18

Schesser, Bartra Sara Celinda. "Outer membrane proteins of Yersinia pestis : Ail and OmpA." Doctoral thesis, Umeå universitet, Institutionen för molekylärbiologi (Teknisk-naturvetenskaplig fakultet), 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-33956.

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A vast number of studies have been completed on the virulence determinants of Yersinia spp.; however, the focus of many of these studies has been on the virulence plasmid and the plasmid-encoded Type three secretion system. Nevertheless, many chromosomal genes whose products are directly involved in virulence have also been identified. Some of these critical virulence determinants are outer membrane proteins. Outer membrane proteins of Gram-negative bacteria often have important physiological roles; however, some have also been found to be important for pathogenesis. In this thesis, we investigated two Yersinia. pestis outer membrane proteins, Ail and OmpA, and their roles in virulence. We provide evidence that Y. pestis Ail is a highly expressed outer membrane protein that is absolutely essential for Y. pestis to resist the killing action of the complement system present in human blood and tissues, as well as the blood and tissues of other mammalian hosts. Furthermore, Ail was important for virulence in a Y. pestis-Canorhabditis elegans model of infection.The work in this thesis also provided the first evidence that another surface-exposed outer membrane protein, termed OmpA, is required for both Yersinia pseudotuberculosis and Y. pestis to survive and proliferate intracellularly in macrophages. Finally, we provide evidence that Y. pestis has a functional small RNA MicA that controls the expression of OmpA. This is the first demonstration of sRNA-mediated regulation of a Yersinia virulence factor. This work has paved the way for future studies on the role of outer membrane proteins in virulence, particularly the role of Ail and OmpA.

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Humphreys, Sue. "Isolation and characterisation of a Vibrio cholerae ompR homologue." Thesis, University of Leicester, 1997. http://hdl.handle.net/2381/30363.

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Vibrio cholerae is the pathogenic agent of the diarrhoeal disease cholera and the major determinant of the disease is the elaboration by the bacteria of the potent enterotoxin cholera toxin (CT). In order to successfully colonise a host V. cholerae must co-ordinately regulate the expression of genes necessary for survival and virulence. ToxR regulates the expression of 17 virulence genes including CT in response to environmental signals like temperature, pH and osmolarity. The change in environment from the external to the human host activates ToxR and the expression of virulence genes under its control. Although this regulon is well characterised it is possible that other regulators are involved. Two-component regulators are a family of proteins that have been isolated from different bacteria which control gene expression in response to environmental signals. The proteins in the family share a high degree of similarity which was exploited in the design of degenerate primers that were used successfully to amplify four response regulator gene fragments from the V. cholerae chromosome. The complete sequence of one of the response regulator fragments has been cloned and shares 80% identity to ompR from E. coli. The sequence of a sensor gene 40% similar to envZ from E. coli has been identified downstream of the V. cholerae gene indicating that the two genes may form part of a two-component regulatory system. The two genes complement E. coli ompR and envZ mutants by altering the expression of E. coli porins indicating that they share functional similarity. Preliminary studies in V. cholerae however, show that the genes do not control porin expression under the conditions analysed. Mutation of the V. cholerae ompR/ envZ homologues will show what proteins are regulated by this system in response to varying environmental signals and whether they play any role in virulence.

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Ibáñez, Gabriela, and Pedro Villa. "Retos y desafíos para los Editores Peruanos y Latinoamericanos. El camino a seguir." Universidad Peruana de Ciencias Aplicadas (UPC), 2018. http://hdl.handle.net/10757/624243.

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Seminario realizado los días miércoles 25 y jueves 26 de julio de 2018, desde la 23 Feria Internacional del Libro de Lima.
Conferencia realizada en el Seminario de la OMPI en Gestión del Derecho de Autor en la Industria Editorial en la Era Digital El Seminario en Gestión del Derecho de Autor en la Industria Editorial en la Era Digital, permitirá conocer de cerca los nuevos desafíos que afronta la industriad editorial en el nuevo entorno digital y los nuevos modelos de negocios que se plantean. Así como compartir la nueva iniciativa de la OMPI para el Círculo de editores, a fin de promover lazos de cooperación e identificar los mayores problemas que afrontan los editores locales y el tipo de cooperación que necesitan.

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García, Giménez Elena. "Regulación electrostática del transporte iónica en el poro bacterial OmpF." Doctoral thesis, Universitat Jaume I, 2009. http://hdl.handle.net/10803/384627.

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El canal iónico OmpF se encuentra en la membrana externa de la bacteria Escherichia coli. Este canal forma un poro ancho a través de la membrana que permite el intercambio de iones y solutos entre los lados periplásmico y extracelular. La regulación del transporte de iones a través de él está fundamentalmente dominada por interacciones electrostáticas de largo alcance. Es por ello que las propiedades del canal tienen una dependencia con la concentración absoluta de sal (manteniendo constante el gradiente de concentración) y con el pH del medio. El pH modifica el estado de carga de los residuos ionizables del canal. De hecho, la modificación del pH de las disoluciones adyacentes al canal favorece una distribución asimétrica de la carga convirtiendo un canal prácticamente óhmico en un canal rectificador de la corriente. Asimismo, las medidas del potencial a corriente cero en condiciones asimétricas de pH proporcionan información sobre la concentración de carga fija positiva y negativa en una distribución bipolar en base a lo que el formalismo Poisson-Nernst-Planck predice para una membrana bipolar con un balance equilibrado entre la concentración de carga positiva y negativa: una selectividad direccional. Las medidas de selectividad realizadas en disoluciones con diferentes electrolitos permiten la identificación de otras contribuciones a la selectividad. Por una parte, medidas realizadas con distintos iones monovalentes demuestran el papel de la difusión iónica en la selectividad. Esta contribución es debida a la diferente movilidad de los cationes y aniones de la disolución. Por otra parte, medidas realizadas en presencia de cationes divalentes sugieren la existencia de un binding site de cationes divalentes en el canal, con la consecuente posibilidad de que se produzca un fenómeno de inversión de carga en el canal. Sin embargo, serán necesarios estudios con mutantes del canal OmpF para ver sin ninguna ambiguedad que el fenómeno de inversión de carga puede tener lugar.

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Tano, Daniel, and Gustaf Dahlbäck. "Insiderhandel under återköpsprogram på Nasdaq OMXS : En sammankoppling med signaleringshypotesen." Thesis, Uppsala universitet, Företagsekonomiska institutionen, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-230232.

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Studien undersöker om andelen insiderhandel under återköpsprogram kan motivera signaleringshypotesen som förekommande anledning till att återköpsprogram genomförs. Studien testar först om en abnormal avkastning uppvisas under återköpsprogrammens löptid. Vidare sammankopplas återköp med andelen insiderhandel som genomförs under återköpsprogrammen, vars resultat jämförs med kontrollföretag. Studien sträcker sig över perioden 2000-03-10 – 2012-12-31, där urvalet för studien är de företag som någon gång under perioden är börsnoterade och genomför minst ett återköpsprogram. Studien visar på abnormal avkastning under återköpsprogram och visar även att insiders köper upp högre andelar av utestående aktier under återköpsprogram än i kontrollföretagen. Resultatet indikerar att andelen insiderhandel under återköpsprogram kan motivera signaleringshypotesen.
The paper examines whether patterns of insider transactions during share repurchases can motivate the signaling hypothesis as a reason for repurchases. It examines whether companies that repurchase shares show an abnormal return during the span of the program. It also examines if patterns showing increased insider transactions amongst the companies who actualized share repurchase programs exist, compared to matching firms which haven’t repurchased shares. The study includes share repurchases and insider transactions during the period 03/10/2000-12/31/2012. The study shows an abnormal return for companies repurchasing shares and also concludes that insiders tend to buy a larger share of stocks during share repurchases than in the matching firms. The result of the study indicates that the degree of insider trading during share repurchases may motivate the signaling hypothesis.

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Higgins, Anna Juman. "The mechanism of BAM-assisted OMP folding." Thesis, University of Leeds, 2018. http://etheses.whiterose.ac.uk/22507/.

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Outer membrane proteins (OMPs) mediate the survival and pathogenicity of Gram negative bacteria. The biogenesis of these proteins, however, presents problems as they must be transported to, inserted and folded correctly in the outer membrane in the absence of ATP. This problem is resolved by the β-barrel assembly machinery (BAM) complex: a ~203 kDa complex of five proteins (BamA-E) that enables the membrane insertion and folding of substrate OMPs on a physiological timescale. Despite available crystal structures, the mechanism of this vital protein complex remains poorly understood. In this thesis I use a variety of structural and biochemical tools to probe the nature of BAM-assisted OMP folding, particularly the role of BamA dynamics. Successful purification of the intact BAM complex in the detergent DDM allowed the first cryo-electron microscopy structure of the complex to be obtained, at a resolution of 4.9 Å. This reveals the intact BAM complex with BamA in a laterally-open conformation in which the first (β1) and last (β16) strands of the barrel are no longer hydrogen bonded. In addition, biochemical assays provide the first in vitro evidence of the functional importance of BamA lateral gating in OMP folding. These assays demonstrate that in a reconstituted system utilising the BAM complex, inhibiting the lateral gating of BamA by incorporating new disulphide bonds diminishes the ability of BAM to assist substrate folding. This is shown with two different OMP substrates, tOmpA (the β-barrel domain of OmpA) and OmpT. In synthetic lipids, however, the presence of prefolded BamA is sufficient to aid substrate folding and inhibition of lateral gating by disulphide bonding in this case does not diminish the catalytic effect. The results indicate that BamA likely adopts different roles depending on substrate and lipid. Furthermore, this thesis discusses preliminary experiments towards determining the significance of the β-signal: a conserved sequence found towards the C-terminus of OMPs hypothesised to be important for recognition by BamA. The results show that while some mutations may slow the protein's intrinsic folding into the membrane they do not affect the apparent BamA-catalysed folding rate. However, other single amino-acid substitutions appear to incur a large energetic penalty, rendering the protein incapable of adopting its stable β-barrel structure. Combined, the data allow us to begin dissecting the mechanism of BAM-assisted folding of OMPs, particularly the role of BamA in passive membrane destabilization or active lateral opening.

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Kaye, Elena Cortizas. "The Function of Outer Membrane Protein A (OmpA) in Yersinia pestis." Scholarly Repository, 2010. http://scholarlyrepository.miami.edu/oa_theses/58.

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The outer membrane protein OmpA is one of the major outer membrane proteins in many species of bacteria, including the Yersiniae. Our goal was to explore the role of OmpA in Y. pestis. This encompasses the ability of Yersinia to infect and survive within macrophages, as well as to resist antimicrobial compounds. Our laboratory found that a delta ompA mutant is impaired in a macrophage-associated infectivity assay. We also found that OmpA might play a role in the ability of the bacteria to resist antimicrobial peptides, specifically polymyxin B. Aditionally, we assessed the differences in OmpA of Y. pestis and E. coli, and determined that the characteristics we have observed in Y. pestis are unique compared to what has previously been described in E. coli. Our results indicate that Y. pestis OmpA might act through known pathways of antimicrobial resistance such as the PhoPQ two-component regulatory system, although further experiments are needed to determine the precise mechanism of function OmpA. Overall, our project characterizes the different functions of OmpA in Y. pestis, both as a key player in intracellular survival and as a necessary component in conferring resistance to antimicrobial peptides.

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OMPI, OMPI. "Principales tratados en materia de propiedad industrial administrados por la OMPI." Pontificia Universidad Católica del Perú, 2013. http://repositorio.pucp.edu.pe/index/handle/123456789/116601.

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Bolla, Jean-Michel. "Assemblage et topologie d'une protéine majeure de l'enveloppe d'Escherichia coli : OmpF." Aix-Marseille 2, 1990. http://www.theses.fr/1990AIX22014.

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L'organisation sub-cellulaire des bacteries gram negatifs est definie par quatre compartiments: le cytoplasme, la membrane interne ou cytoplasmique, le periplasme et la membrane externe. Chaque compartiment contient des proteines dont la conformation, la topologie et la fonction sont parfaitement definies. Or, toutes les proteines sont synthetisees dans le cytoplasme, elles doivent donc posseder des informations structurales et/ou conformationnelles qui permettent a la machinerie cellulaire de les acheminer vers leur compartiment fonctionnel. Nous avons analyse l'assemblage et la topologie de ompf, une proteine majeure de la membrane externe d'escherichia coli. Elles est organisee sous forme trimere fortement associee au lipopolysaccharide, permet la diffusion de solutes de petit poids moleculaire et presente une fonction recepteur pour certains phages et certaines colicines. Au cours de la biosynthese et de l'assemblage, quatre formes differentes de la molecule ont ete caracterisees: la forme precurseur clivee en forme monomere qui tres rapidement donne naissance a une forme trimere metastable; un changement de conformation donne naissance au trimere natif. La trimerisation doit se produire rapidement apres le clivage du peptide signal et en presence de synthese lipidique; si les deux processus sont decouples, le monomere evolue vers une conformation inadequate pour l'integration dans la membrane. Par ailleurs, la region c-terminale est necessaire a la proteine afin d'assurer la stabilite de son assemblage. En etudiant plusieurs proteines hybrides, nous avons defini les regions exposees de la molecule intervenant dans le site recepteur des colicines a et n. Ainsi, nous avons apprehende la topologie d'une proteine multimerique dans une membrane bacterienne et etabli des relations entre la structure, l'assemblage et les fonctions d'une telle molecule

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Caby, Marine. "Rôle du phosphorelais EnvZ/OmpR chez la bactérie phytopathogène Dickeya dadantii." Thesis, Lille 1, 2020. http://www.theses.fr/2020LIL1S108.

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Au cours de leur vie, les bactéries pathogènes sont confrontées à de nombreuses variations environnementales souvent appelées stress, notamment au cours du processus infectieux. Pour survivre et coloniser avec succès son hôte, la bactérie doit percevoir ce nouvel et hostile environnement pour s'y adapter rapidement. C'est le rôle principal assigné aux phosphorelais. Ces systèmes sont composés d'un couple capteur/régulateur. Sous l'action d'un stimulus, le capteur s'autophosphoryle et transmet son phosphate au régulateur, qui module l’activité d’un ensemble de gènes cibles permettant l'adaptation au nouvel environnement. Notre modèle expérimental Dickeya dadantii est une bactérie phytopathogène nécrotrophe responsable de la maladie de la pourriture molle chez un large spectre de plantes hôtes. Les variations du pH et d’osmolarité sont deux des stress souvent rencontrés et combattus par les bactéries pathogènes. Les phosphorelais EnvZ/OmpR et RcsCDB sont deux systèmes majeurs répondant à ces stress. Le laboratoire avait précédemment démontré que le niveau d'activation du système RcsCDB dépendait de la concentration en glucanes périplasmiques osmorégulés (OPG). Leur concentration est d’autant plus élevée dans le périplasme que l’osmolarité du milieu est basse ce qui fait des OPG un intermédiaire essentiel dans la perception de l'osmolarité. Cela nous a poussé à éclaircir la relation entre EnvZ/OmpR et les OPG. Dans ce travail, j’ai montré que, contrairement à l'activation du système RcsCDB, l'activation du système EnvZ/OmpR ne dépend pas de la concentration des OPG, tout en nécessitant leur présence pour l’activation correcte de ce phosphorelais. Pour mieux comprendre le rôle du système EnvZ/OmpR chez D. dadantii, l'activité de ce système a été étudiée in vivo et in planta. Alors que le système EnvZ/OmpR est activé dans un milieu à pH acide et à une osmolarité élevée chez E. coli, mes travaux montrent que seule la variation du pH active ce phosphorelais. De plus, contrairement à E. coli qui possède deux porines majeures, il ne semblait exister qu’une seule porine majeure chez D. dadantii. Mes études ont cependant révélé l’existence d’une seconde porine apparaissant à pH acide in vivo et in planta. Ces deux porines de type OmpF sont régulées par le pH via OmpR. Passée une adaptation de quelques heures dans l’hôte, le profil de ces porines dans l’enveloppe ne change plus durant l’infection. Pourtant, le niveau d’activation d’EnvZ/OmpR durant cette même période fluctue. Ainsi, au moins un autre paramètre environnemental module l’activation de EnvZ/OmpR in planta. Enfin, l’absence de variation des porines dans l’enveloppe durant cette même période suggère qu’un autre régulateur, peut-être RcsCDB, permettrait le maintien de leur niveau d’expression
During their lifetime, pathogenic bacteria are confronted with numerous environmental variations often referred to stress, particularly during infection. In order to survive and successfully colonize its host, the bacterium must perceive this new and dangerous environment to adapt quickly. This is the main role assigned to phosphorelays. These systems are composed of a sensor and a cognate regulator. Under the action of a stimulus, the sensor autophosphorylates and transmits the phosphate group to its regulator, which in turn modulates the activity of a set of target genes allowing adaptation to the new environment. Our experimental model Dickeya dadantii is a necrotrophic plant pathogen bacterium responsible for soft rot disease in a wide range of plant species. The variation of pH and osmolarity are two stresses often faced and fought by pathogenic bacteria. EnvZ/OmpR and RcsCDB phosphorelays are two major systems known to respond to these stresses. The laboratory had previously demonstrated that the level of activation of the RcsCDB system was dependent on the concentration of periplasmic osmoregulated glucans (OPG). Their concentration in the periplasm increases as the medium osmolarity decreases, making OPGs a major intermediate in the perception of osmolarity. This prompted us to decipher the relationship between EnvZ/OmpR and OPGs. I showed that, unlike for the activation of the RcsCDB system, the activation of EnvZ/OmpR doesn’t depend on the concentration of OPGs, but still requires its presence for proper activation of the phosphorelay. To go deeper into the EnvZ/OmpR system, activities of this system have been studied in vivo and in planta. While the EnvZ/OmpR system is activated in a medium with an acidic pH and a high osmolarity in E. coli, my work shows that only pH variation activates this phosphorelay in D. dadantii. In addition, only one major porin (versus two in E. coli) was previously detected in D. dadantii. My studies revealed the existence of a second porin expressed at acidic pH in vivo and in planta. These two OmpF-like porins are regulated by the pH via OmpR. After adaptation for a few hours in planta, the pattern of these two porines remains the same over the rest of the infection. However, the level of OmpR activation during the same period fluctuates indicating that at least one other environmental parameter modulates the activation of EnvZ/OmpR in planta. The steady state level of the porines in the envelope during this same period suggests that another regulatory system, perhaps RcsCDB may maintain their expression level

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Strafonda, Giovanni Battista. "Traduzione del libro di ricette - "Die besten Kochrezepte aus Omas Zeiten"." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amslaurea.unibo.it/7514/.

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Abstract Questo elaborato consta della traduzione di un libro di ricette scritto in lingua tedesca, il cui titolo originale è “Die besten Kochrezepte aus Omas Zeiten”. Questa tesina propone una traduzione delle varie ricette, onde offrire uno sguardo alla cucina tedesca antica e casalinga, nonché alle differenze storiche, linguistiche, culturali che queste hanno con i piatti italiani e nostrani. A questo scopo, infatti, è stato fornito un identikit storico-culturale sull'origine e le curiosità di ogni piatto, aggiungendo nella maggior parte dei casi anche un commento alla traduzione, alla lingua e al lessico utilizzato. Questo lavoro è incentrato sull'immagine “sociale” e culturale della “Nonna” tedesca, o più in generale della massaia, abile preparatrice di deliziosi manicaretti. Ogni piatto è ordinato secondo una sezione, che scandisce l'ordine delle pietanze e le suddivide nelle varie categorie, facilitandone il riconoscimento e il confronto con piatti italiani.

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Kemp, Elizabeth Helen. "A study of the ompT gene of Escherichia coli K-12." Thesis, University of Warwick, 1988. http://wrap.warwick.ac.uk/109990/.

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The ompT gene of E. coll encodes a 40 kd outer membrane protein (OmpT) which, in vitro, exhibits proteolytic activity towards the ferric-enterochelin receptor protein. In this study the ompT gene was cloned from E. coli K-12 on a 4.3 kb EcoRI DNA-Fragment. Subcloning of this fragment, in conjunction with maxi-cell analysis, demonstrated that ompT was located on a 1.5 kb Pstl-Smal DNA fragment. DNA sequence analysis revealed that the Pstl-Smal fragment contained an open reading frame (ORF) of 951 bp, the latter having a coding capacity of 35.6 kd. This deduced molecular weight was somewhat smaller than the molecular weight of 42 kd estimated by SDS-PAGE for pro-OmpT. Potential -10 and -35 promoter consensus sequences were identified upstream from the ompT coding region as was a putative ribosome binding site. A DNA sequence showing homology to a consensus sequence present in the putative promoter regions of iron- regulated genes, was also located upstream from the ompT coding region. With regard to the deduced amino acid sequence of OmpT, a potential signal sequence was found at the amino-terminal of the protein which could direct export from the cell cytoplasm. The protein was also examined for amino acid sequences displaying homology to other outer membrane proteins, but none were identified. OmpT-phoA gene fusions were constructed in order to assess the ability of the ompT transcription/translation initiation signals to drive the expression of cloned heterologous genes in E. coli. OmpT-PhoA fusion proteins were indeed produced and these were exported to the periplasm of the cell. Synthesis of the chimeric proteins was found to be 5-6 fold higher at 37°C than at 30°C which seemed to reflect the normal temperature-dependent production of the OmpT protein. Both ompT-lacZ operon and protein fusions were also created in an attempt to define the stage at which temperature affected the synthesis of OmpT. Studies indicated that this occurred at some post-transcriptional step. The effect of the envZ allele on the expression of ompT was also investigated. This mutation appeared to reduce the level of transcription of ompT as Indicated by studies using the ompT-phoA and ompT-lacZ fusions.

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30

Mobasheri, Hamid. "Biophysical study of the structure and function of single ionic channels." Thesis, University of East Anglia, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301941.

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Madoroba, E., and NB Momba. "Prevalence of Vibrio cholerae in rivers of Mpumalanga province, South Africa as revealed by polyphasic characterization." African Journal of Biotechnology, 2010. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1001241.

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Cholera is a life-threatening diarrhoeal disease, which mainly affects inhabitants of developing countries due to poor socio-economic conditions and lack of access to potable water and sanitation. Toxigenic Vibrio cholerae are the aetiological agents of cholera. These bacteria are autochthonous to aquatic environments, hence water plays a central role both in the epidemiology and transmission of cholera. The aim of this study was to determine the prevalence of V. cholerae from 32 sites of major rivers in Mpumalanga province of South Africa using a polyphasic approach. Water samples (594) collected over for 4 months were cultured on thiosulphate-citrate-bile salt-sucrose agar, and oxidase positive (88) isolates were subjected to biochemical tests and duplex polymerase chain reaction targeting the outer membrane protein (ompW) and cholera toxin (ctxAB) genes. All ompW PCR positive V. cholerae isolates were subjected to rfbO1 PCR. Fifteen isolates from Crocodile, Komati and Gutshwa rivers were assigned to V. cholerae by both biochemical tests and PCR, of which no isolates were positive for ctxAB and rfbO1 genes. The polyphasic approach was effective at revealing non-O1 and non-toxigenic V. cholerae in some rivers. Such information is important for raising awareness regarding the presence of V. cholerae so that precautionary measures are taken on time.

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Vienrich, Fausto, and Dimiter Gantchev. "Tratado de Marrakech:Panorama general. Accesibilidad, discapacidad e implementación del Tratado de Marrakech." Universidad Peruana de Ciencias Aplicadas (UPC), 2018. http://hdl.handle.net/10757/624240.

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Seminario realizado los días miércoles 25 y jueves 26 de julio de 2018, desde la 23 Feria Internacional del Libro de Lima.
Conferencia realizada en el Seminario de la OMPI en Gestión del Derecho de Autor en la Industria Editorial en la Era Digital El Seminario en Gestión del Derecho de Autor en la Industria Editorial en la Era Digital, permitirá conocer de cerca los nuevos desafíos que afronta la industriad editorial en el nuevo entorno digital y los nuevos modelos de negocios que se plantean. Así como compartir la nueva iniciativa de la OMPI para el Círculo de editores, a fin de promover lazos de cooperación e identificar los mayores problemas que afrontan los editores locales y el tipo de cooperación que necesitan.

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Öhman, Mikael. "a Data-Warehouse Solution for OMS Data Management." Thesis, Umeå universitet, Institutionen för datavetenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-80688.

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A database system for storing and querying data of a dynamic schema has been developed based on the kdb+ database management system and the q programming language for use in a financial setting of order and execution services. Some basic assumptions of mandatory fields of the data to be stored are made including that the data are time-series based.A dynamic schema enables an Order-Management System (OMS) to store information not suitable or usable when stored in log files or traditional databases. Log files are linear, cannot be queried effectively and are not suitable for the volumes produced by modern OMSs. Traditional databases are typically row-oriented which does not suit time-series based data and rely on the relational model which uses statically typed sets to store relations.The created system includes software that is capable of mining the actual schema stored in the database and visualize it. This enables ease of exploratory querying and production of applications which use the database. A feedhandler has been created optimized for handling high volumes of data. Volumes in finance are steadily growing as the industry continues to adopt computer automation of tasks. Feedhandler performance is important to reduce latency and for cost savings as a result of not having to scale horizontally. A study of the area of algorithmic trading has been performed with focus on transaction-cost analysis. Fundamental algorithms have been reviewed.A proof of concept application has been created that simulates an OMS storing logs on the execution of a Volume Weighted Average Price (VWAP) trading algorithm. The stored logs are then used in order to improve the performance of the trading algorithm through basic data mining and machine learning techniques. The actual learning algorithm focuses on predicting intraday volume patterns.

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Mauricio, Orcón Cendik Leonardo. "Tendencia y desarrollo de los operadores móviles virtuales (OMVS) en el Perú." Master's thesis, Pontificia Universidad Católica del Perú, 2015. http://tesis.pucp.edu.pe/repositorio/handle/123456789/6525.

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El modelo del Operador Móvil Virtual (MVNO – Mobile Virtual Network Operator) hace referencia a empresas que ofrecen servicios de comunicaciones móviles sin contar con frecuencias de espectro ni con infraestructura de red de acceso. Para poder operar estas empresas realizan un acuerdo con un Operador Móvil de Red (MNO – Mobile Network Operator) que le brindan capacidad en su red en base a un acuerdo económico. Este modelo de negocio se ha venido desarrollando desde hace más de 11 años en mercados sostenibles como EEUU y Europa, manifestándose generalmente en mercados saturados como otra alternativa que tienen los OMRs para conseguir nuevas líneas de ingresos. Por lo general este modelo de negocio le ha dado a los mercados de comunicaciones móviles mayor competencia, mayor desarrollo y ofertas mejor customizables para las necesidades de los clientes. Este trabajo se sostendrá en base a experiencias internacionales, características del mercado móvil peruano (como la composición del market share) y aspectos regulatorios. Además se realizarán entrevistas con expertos, con los que se analizará si el mercado Peruano es un mercado donde existen posibilidades para que puedan desarrollarse este tipo de empresas. También se analizará la cadena de valor y su relación directa con el tipo de OMV que una empresa puede implementar (Full OMV, Proveedor de Servicios Avanzado, Proveedor de Servicios o Revendedor) y se presentaran las posibles estrategias que deberían seguir las empresas que deseen ingresar a este mercado, ya sea las estrategias basadas en precios con descuentos agresivos y un enfoque masivo o estrategias basadas en servicios con más cantidad de opciones. Estas opciones de servicios pueden basarse en comunidades y segmentos (jóvenes o grupos sociales), en servicios Premium de valor agregado, en convergencia fijo-móvil, enfocar el servicio a empresas, dar servicios con buenos planes de roaming o brindar servicios específicos por ejemplo para conexiones machine to machine (M2M) o servicios basados en la localización (LBS).
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Gantchev, Dimiter. "Propiedad Intelectual y Derecho de Autor para Editores. Una panorámica de la publicación de OMPI “Del papel a las plataformas”." Universidad Peruana de Ciencias Aplicadas (UPC), 2018. http://hdl.handle.net/10757/624233.

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Seminario realizado los días miércoles 25 y jueves 26 de julio de 2018, desde la 23 Feria Internacional del Libro de Lima.
Conferencia realizada en el Seminario de la OMPI en Gestión del Derecho de Autor en la Industria Editorial en la Era Digital El Seminario en Gestión del Derecho de Autor en la Industria Editorial en la Era Digital, permitirá conocer de cerca los nuevos desafíos que afronta la industriad editorial en el nuevo entorno digital y los nuevos modelos de negocios que se plantean. Así como compartir la nueva iniciativa de la OMPI para el Círculo de editores, a fin de promover lazos de cooperación e identificar los mayores problemas que afrontan los editores locales y el tipo de cooperación que necesitan.

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Vienrich, Fausto, and Dimiter Gantchev. "Iniciativa de la OMPI para el Círculo de Editores a fin de promover los lazos de cooperación. Identificando necesidades, retos, mejores prácticas y formas de cooperación." Universidad Peruana de Ciencias Aplicadas (UPC), 2018. http://hdl.handle.net/10757/624242.

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Seminario realizado los días miércoles 25 y jueves 26 de julio de 2018, desde la 23 Feria Internacional del Libro de Lima.
Mesa redonda de la OMPI sobre el círculo de editores realizada en el Seminario de la OMPI en Gestión del Derecho de Autor en la Industria Editorial en la Era Digital El Seminario en Gestión del Derecho de Autor en la Industria Editorial en la Era Digital, permitirá conocer de cerca los nuevos desafíos que afronta la industriad editorial en el nuevo entorno digital y los nuevos modelos de negocios que se plantean. Así como compartir la nueva iniciativa de la OMPI para el Círculo de editores, a fin de promover lazos de cooperación e identificar los mayores problemas que afrontan los editores locales y el tipo de cooperación que necesitan.

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Villa, Pedro, and Diego Echevarría. "Gestión de los derechos en el Entorno Digital – Oportunidades y Desafíos para Perú y Latino América." Universidad Peruana de Ciencias Aplicadas (UPC), 2018. http://hdl.handle.net/10757/624244.

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Seminario realizado los días miércoles 25 y jueves 26 de julio de 2018, desde la 23 Feria Internacional del Libro de Lima.
Conferencia realizada en el Seminario de la OMPI en Gestión del Derecho de Autor en la Industria Editorial en la Era Digital El Seminario en Gestión del Derecho de Autor en la Industria Editorial en la Era Digital, permitirá conocer de cerca los nuevos desafíos que afronta la industriad editorial en el nuevo entorno digital y los nuevos modelos de negocios que se plantean. Así como compartir la nueva iniciativa de la OMPI para el Círculo de editores, a fin de promover lazos de cooperación e identificar los mayores problemas que afrontan los editores locales y el tipo de cooperación que necesitan.

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Thotakura, Gangadaar. "Structural prediction analysis of ehrlichia chaffeensis outer membrane proteins, p28 Omp-14 and p28 Omp-19 assessed by circular dichrosim and porin assays." Thesis, Kansas State University, 2011. http://hdl.handle.net/2097/9098.

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Master of Science
Department of Diagnostic Medicine/Pathobiology
Roman Reddy R. Ganta
Ehrlichia chaffeensis, a Gram-negative organism belonging to the order Rickettsiales, is responsible for an emerging infectious disease in humans, the human monocytic ehrlichiosis. E. chaffeensis also infects several other vertebrate hosts including dogs, goats, coyotes and white tailed deers. This organism is transmitted by an infected tick, Amblyomma americanum. The exact pathogenic mechanisms involved for the persistence of the pathogen in vertebrate hosts are still unclear. E. chaffeensis protein expression varies significantly in vertebrate and tick hosts. Differentially expressed proteins include the immunodominant outer membrane proteins encoded by the p28-Omp multigene locus. The p28-Omp 14 is expressed primarily in tick cells and the p28-Omp 19 is the major expressed protein in macrophages both under in vitro and in vivo conditions. The objective of this study is to prepare recombinant proteins and use them to assess the secondary structures and protein functions. The protein sequences were analyzed with the aid of bioinformatics programs to make structural predictions. The analysis suggested the presence of eight β barrel structures for both the p28-Omp proteins. The coding sequence of the p28-Omp genes were cloned and over expressions of proteins in in E. coli was accomplished by using the plasmid expression construct, pET28. The proteins were purified to near homogeneity and used to refold using detergents to mimic native protein structure in the bacterial outer membrane. Refolding of proteins was analyzed by two methods; SDS-PAGE and Circular Dichroism. The Circular dichroism spectroscopy analysis suggested the formation of β-sheet structures of proteins in micelles formed with the detergents. β-sheet structures may have been formed with the hydrophobic domains of the protein imbedded in the micelles. The hydrophilic segments (predicted by bio informatics analysis) may be exposed to the aqueous phase. The recombinant proteins were also iii used to prepare proteoliposomes and tested for the porin activity. The analysis demonstrated the porin activity for both p28-Omp 14 and 19 recombinant proteins by using mono-, di- and tetra- saccharides as well as for amino acid L-glutamine. This study forms the basis for initiating studies to compare the structural difference between the two differentially expressed proteins of E. chaffeensis.

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Barland, Martin. "Motion Planning Framework for Industrial Manipulators using the Open Motion Planning Library (OMPL)." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for teknisk kybernetikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-18422.

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Robotic manipulators are used in many different scenarios these days. If one of these manipulators is moved from one location to another it may require a total reprogramming of that manipulator because of the new environment the robot is working in. This is because the path planning and trajectory planning scheme which works in one environment might not be suitable in another. This text takes a look at how an intuitive and easy to use motion planning framework for finding paths in different static environments or scenarios can be made. The use of the Open Motion Planning Library has been used for the path planning and second-order cone programming solved by SeDuMi in Matlab has been used for finding the time-optimal trajectory.

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Rosenius, Niklas, and Gustav Sjöholm. "Arbitrage opportunities on the OMXS : How to capitalize on the ex-dividend effect." Thesis, Umeå universitet, Företagsekonomi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-81173.

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Investors are continuously looking to increase the return on their investments. In an ideal world investors want to increase there return and outperform the market. Theory states that it is impossible to do so without increasing your risk. Arbitrage is a concept where investors are able to generate risk-free returns exceeding the market. Dividend is a common tool for publicly listed firms when rewarding their shareholders. On ex- dividend day, the day after the dividend payout, the stock price should according to theory decrease in order for the valuation of the stock to be held constant. In our research we investigate if there are arbitrage opportunities in connection to the dividend payouts, namely the ex-dividend effect. We want to generalize our results across experimental settings, thus across different stock markets. As a basis for our research we picked the OMXS. We base our research on three theoretical areas: the dividend irrelevancy theory, the efficient market hypothesis and the anchoring theory. The dividend irrelevancy relates to how the stock price ought to behave on ex-dividend day whereas the efficient market hypotheses states that prices on a market fully reflects all available information. Both theories concur that no arbitrage opportunities should be available on the financial market. The anchoring theory highlights the fact that investors formulate an anchor price for financial assets, for example stocks. In our research we aim to formulate a practical method on how to make abnormal returns on the ex dividend effect, based on the anchoring theory. Our census sample consists of dividend-paying firms publicly registered on the OMXS, and consists of 694 observations taken from 2009 to 2012. The sample was picked on the basis of characteristics, for example that the firm has been registered for at least four years and paid dividend one time during the four years of investigation. In order to tests for arbitrage opportunities on ex-dividend day, we used a simple mathematical model measuring the deviation between the price drop cum-dividend day to ex-dividend day, and the dividend amount. We conclude that the price drop differs from the dividend amount, only accounting for a price drop of 0.73 of the dividend amount. Thus, the price drop for each dividend unit is 0.73, in relation to a perfectly efficient market where there should be no difference; hence the price drop would be equal to the dividend amount, 1. Research on the ex-dividend effect is a thoroughly investigated area, where the first research was presented in 1955. Previous research all attempts to explain why there are market anomalies, but none examine how one can capitalize on the findings. In our research we examine if it is possible to make abnormal returns based on a segmenting of stocks, depending on their price volatility. This research is thereby first in examining how to capitalize on found arbitrage opportunities.

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Al-Meer, Jehan Abdulla. "Molecular analysis of the ompR/envZ two-component regulatory system in Bortadella species." Thesis, Imperial College London, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285150.

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Schürmann, Nicole [Verfasser]. "Nachweis und Analyse BamA-assoziierter Faltungsintermediate des OmpA durch ortsgerichtete Fluoreszenzspektroskopie / Nicole Schürmann." Kassel : Universitätsbibliothek Kassel, 2020. http://d-nb.info/122538009X/34.

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Crampton, Michael Craig. "Physiological and genetic evidence for an OmpB signal transduction system in Erwinia chrysanthemi." Master's thesis, University of Cape Town, 1996. http://hdl.handle.net/11427/21410.

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Bibliography: pages 132-155.
In order for bacteria to survive in their environment they must continuely sense signals such as, presence of host organisms, chemical concentrations, or variationsin other physiological parameters. Many bacteria sense their environment through the use of a two component regulatory systems. These systems usually employ the use of two different proteins, a sensor protein and its cognate response regulator. Some bacteria can survive fluctuations in medium osmolarity through the use of a two component signal transduction system. In Escherichia coli and Salmonella typhimurium this two component system includes the EnvZ sensor protein and its cognate response regulator, OmpR. The two genes that code for these proteins are envZ and ompR genes respectively. The two genes together form the ompB operonrespectively. This operon regulates the expression of two outer membrane proteins, OmpF and OmpC in response to medium osmolarity in E. coli.Erwinia chrysanthemi has been found to be sensitive to desication. Proliferation of soft rot, caused by this organism, has also been associated with irrigation. E.chrysanthemi has also been observed to respond to changes in medium osmolarity. Evidence of an ompB operon was thus sought. Outer membrane proteins were isolated using sodium lauroylsarcosine. Three major outer membrane proteins were isolated, namely Ompl (37.5 kd), Omp2 (35.5 kd) and Omp3 (34.5 kd). Increase in medium osmolarity resulted in an increase in expression of Omp3, while Ompl was suppressed. This lends support to the presence of an ompB like signal transduction system in E. chrysanthemi. Growth temperature was shown to have no effect on the expression of the major OMP. Similarly, culture growth phase had no effect on major OMP expression. However, two induced OMP were present from mid log phase onwards.

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44

Dunson, Amanda E. "Regulation of ompA and Its Effect on Shigella Virulence." Ohio University Honors Tutorial College / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ouhonors1400564483.

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45

Postel, Alexander. "Untersuchungen zur Verbreitung und Funktion des äussere-Membran-Proteins OmpW von Salmonella spp." Giessen VVB Laufersweiler, 2008. http://d-nb.info/992325404/34.

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46

McDowell, Eric Todd. "A Tale of Two 'omes: Comparative Genomics and Important Genes in Specialized Tissues." Diss., The University of Arizona, 2010. http://hdl.handle.net/10150/194017.

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Analysis of complex traits like plant specialized metabolism is a difficult task in non-model systems as plant specialized metabolism is controlled by a number of factors such as environment, genotype, age, and tissue. To help address this problem, we have taken a bioinformatic approach that involves sequencing select tissues that are enrichedfor the biosynthesis of specialized metabolites. Using this approach, we have sequenced multiple tissues from a variety of species and compared them against one another. This comparative approach has allowed us to identify some of the genes responsible for the biochemical differences in and between species as well as genes that may be involved in control of specialized tissue development or metabolism. This dissertation begins with a brief introduction of plant metabolism, and pays special attention to historical and present views of plant metabolism, the importance of specialized metabolism, its evolution, and why it is advantageous to study specialized metabolism from specialized tissues like glandular trichomes and rhizomes. To this end, I detail our production and comparisons of glandular trichomes of several Solanum species using next-generation 454 sequencing. I also extensively review the underground stems, or rhizomes, of Viridiplantae. Discussions of our production and comparison of rhizome EST libraries from Zingiber officinale, Curcuma longa, and several Sorghum species are also made. My efforts to lay the groundwork that will hopefully permit functional analysis of interesting genes identified through our sequence comparisons of glandular trichome or rhizome EST libraries, in non-model systems are also discussed.

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47

Maheo, Aurèle. "Improving the Hybrid model MPI+Threads through Applications, Runtimes and Performance tools." Thesis, Versailles-St Quentin en Yvelines, 2015. http://www.theses.fr/2015VERS039V/document.

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Afin de répondre aux besoins de plus en plus importants en puissance de calcul de la part des applicationsnumériques, les supercalculateurs ont dû évoluer et sont ainsi de plus en plus compliqués àprogrammer. Ainsi, en plus de l’apparition des systèmes à mémoire partagée, des architectures ditesNUMA (Non Uniform Memory Access) sont présentes au sein de ces machines, fournissant plusieursniveaux de parallélisme. Une autre contrainte, la diminution de la mémoire disponible par coeur decalcul, doit être soulignée. C’est ainsi que des modèles parallèles tels que MPI (Message Passing Interface)ne permettent plus aux codes scientifiques haute performance de passer à l’echelle et d’exploiterefficacement les machines de calcul, et doivent donc être combinés avec d’autres modèles plus adaptésaux architectures à mémoire partagée. OpenMP, en tant que modèle standardisé, est un choix privilégiépour être combiné avec MPI. Mais mélanger deux modèles avec des paradigmes différents est unet âche compliquée et peut engendrer des goulets d’étranglement qui doivent être identifiés. Cette thèsea pour objectif d’aborder ces limitations et met en avant plusieurs contributions couvrant divers aspects.Notre première contribution permet de r éduire le surcoût des supports exécutifs OpenMP en optimisantle travail d’activation et de synchronisation des threads OpenMP pour les codes MPI+OpenMP. Dansun second temps, nous nous focalisons sur les opérations collectives MPI. Notre contribution a pourbut d’optimiser l’opération MPI Allreduce en réutilisant des unités de calcul inoccupées, et faisant intervenirdes threads OpenMP. Nous introduisons également le concept de collectives unifiées, impliquantdes tâches MPI et des threads OpenMP dans une même opération. Enfin, nous nous intéressons àl’analyse de performance et plus précisément l’instrumentation des applications MPI+OpenMP, et notredernière contribution consiste en l’implémentation et l’ évaluation de l’outil OpenMP Tools API (OMPT)dans le support exécutif OpenMP du framework MPC. Cet outil nous permet d’instrumenter des constructionsOpenMP et de conduire une analyse axée aussi bien du côté des applications que dessupports d’exécution
To provide increasing computational power for numerical simulations, supercomputers evolved and arenow more and more complex to program. Indeed, after the appearance of shared memory systemsemerged architectures such as NUMA (Non Uniform Memory Access) systems, providing several levelsof parallelism. Another constraint, the decreasing amount of memory per compute core, has to bementioned. Therefore, parallel models such as Message Passing Interface (MPI) are no more sufficientto enable scalability of High Performance applications, and have to be coupled with another modeladapted to shared memory architectures. OpenMP, as a de facto standard, is a good candidate to bemixed with MPI. The principle is to use this model to augment legacy codes already parallelized withMPI. But hybridizing scientific codes is a complex task, bottlenecks exist and need to be identified. Thisthesis tackles these limitations and proposes different contributions following various aspects. Our firstcontribution reduces the overhead of the OpenMP layer by optimizing the creation and synchronizationof threads for MPI+OpenMP codes. On a second time, we target MPI collective operations. Our contributionconsists in proposing a technique to exploit idle cores in order to help the operation, with theexample of MPI Allreduce collective. We also introduce unified Collectives involving both MPI tasks andOpenMP threads. Finally, we focus on performance analysis of hybrid MPI+OpenMP codes, and ourlast contribution consists in the implementation of OpenMP Tools API (OMPT), an instrumentation tool,inside the OpenMP runtime of MPC framework. This tool allows us to instrument and profile OpenMPconstructs and allows the analysis of both runtime and application sides

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48

Freitas, Norma Suely de Lima. "Análise das seqüências do gene ompA de Chlamydia trachomatis isoladas do trato genital de mulheres inférteis e gestantes em Manaus – Amazonas." Universidade Federal do Amazonas, 2012. http://tede.ufam.edu.br/handle/tede/4301.

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Despite the high prevalence and the risks associated with Chlamydia trachomatis in Brazil and other countries, little is known about the distribution of genotypes in Brazil and the biological variability of this important transmitting agent of sexually transmitted diseases (STDs). The absence of an inquiry routine for C. trachomatis and effective treatments can cause serious complications and consequences for individuals as pelvic inflammatory disease, infertility, ectopic pregnancy and neonatal infections. Currently, C. trachomatis presents 19 serotypes A-C associated with trachoma, D-K responsible for urogenital infections and L1, L2 and L3, agents responsible for lymphogranuloma venereum syndrome. The MOMP, which is recognized as the immunodominant antigen encoded by the ompA gene displays a large area of nucleotide variation of four variable domains (VDI to VDIV). Studies suggest that mutations occur frequently among genotypes and that these mutations may indicate differences between the immunogenic MOMP genotypes of C. trachomatis. The present work aims to identify the genotypes from samples positive by PCR for C. trachomatis in women diagnosed with infertility and with pregnant women in the city of Manaus, Amazonas - Brazil, in addition to sequence and analyze the ompA gene. The study population consisted of 96 infertile women and 53 pregnant women. Genotyping was performed by the technique of Polymerase Chain Reaction (PCR) from the ompA gene sequence and the following genotypes were identified in pregnant women: D [50.0%], E [25.0%] and F [12.5%] and I [12.5%]. In infertile women genotypes were identified: E [16.7%] F [16,7%] and K [66,7%]. The frequency of genotype K and D found in this study are considered high (66,7%) and (50,0%) and for phylogenetic analysis, we found that the genotypes analyzed shares the same ancestor. It is suggested that these variations in the sequences of genotypes identified arise from point mutations, or possibly by VD recombination in MOMP. The VDII region showed to be the most variable in the sequences analyzed.
Apesar da alta prevalência e dos riscos associados à Chlamydia trachomatis no Brasil e outros países do mundo, pouco se conhece sobre a distribuição dos genótipos no Brasil e a variabilidade biológica deste importante agente transmissor de doenças sexualmente transmissíveis (DST). A ausência de uma investigação rotineira para C. trachomatis e tratamentos efetivos pode originar sérias complicações e conseqüências para os indivíduos como doença inflamatória pélvica, infertilidade, gravidez ectópica e infecções neonatais. Atualmente, a C. trachomatis apresenta 19 sorotipos: A-C associados ao tracoma, D-K responsáveis por infecções urogenitais e L1, L2 e L3, agentes responsáveis pela síndrome do linfogranuloma venéreo. A MOMP, reconhecida como o antígeno imunodominante codificado pelo o gene ompA, exibe uma extensa área de variação nucleotídica sendo por sua vez, conferido por quatro domínios variáveis (VDI a VDIV). Estudos sugerem que as mutações ocorrem frequentemente entre os genótipos e que essas mutações podem indicar diferenças imunogênicas entre as MOMP de genótipos de C. trachomatis. O presente trabalho tem por objetivo identificar os genótipos a partir de amostras positivas por PCR para C. trachomatis de mulheres com diagnóstico de infertilidade e em gestantes na cidade de Manaus, Amazonas – Brasil, além de sequenciar e analisar o gene ompA. A população de estudo consistiu de 96 mulheres inférteis e 53 mulheres gestantes. A genotipagem foi feita pela a técnica de Reação em Cadeia de Polimerase (PCR) a partir da seqüência do gene ompA e os seguintes genótipos foram identificados em gestantes: D [50,0%]; E [25,0%]; F [12,5%] e I [12,5%]. Em mulheres inférteis os genótipos identificados foram: E [16,7%], F [16,7,%] e K [66,7%]. A freqüência de genótipo K e D encontrada neste estudo são consideradas elevadas (66,7%) e (50,0%) e quanto à análise filogenética, verificamos que os genótipos analisados compartilham do mesmo ancestral. Sugere-se que as variações encontradas nas sequências dos genótipos identificados surgem dos pontos de mutação ou possivelmente pela recombinação dos VD na MOMP. A região VDII foi que mais apresentou variações nas seqüências analisadas.

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49

Carpenter, Paul (Paul Matthew). "Running stream-like programs on heterogeneous multi-core systems." Doctoral thesis, Universitat Politècnica de Catalunya, 2011. http://hdl.handle.net/10803/84186.

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All major semiconductor companies are now shipping multi-cores. Phones, PCs, laptops, and mobile internet devices will all require software that can make effective use of these cores. Writing high-performance parallel software is difficult, time-consuming and error prone, increasing both time-to-market and cost. Software outlives hardware; it typically takes longer to develop new software than hardware, and legacy software tends to survive for a long time, during which the number of cores per system will increase. Development and maintenance productivity will be improved if parallelism and technical details are managed by the machine, while the programmer reasons about the application as a whole. Parallel software should be written using domain-specific high-level languages or extensions. These languages reveal implicit parallelism, which would be obscured by a sequential language such as C. When memory allocation and program control are managed by the compiler, the program's structure and data layout can be safely and reliably modified by high-level compiler transformations. One important application domain contains so-called stream programs, which are structured as independent kernels interacting only through one-way channels, called streams. Stream programming is not applicable to all programs, but it arises naturally in audio and video encode and decode, 3D graphics, and digital signal processing. This representation enables high-level transformations, including kernel unrolling and kernel fusion. This thesis develops new compiler and run-time techniques for stream programming. The first part of the thesis is concerned with a statically scheduled stream compiler. It introduces a new static partitioning algorithm, which determines which kernels should be fused, in order to balance the loads on the processors and interconnects. A good partitioning algorithm is crucial if the compiler is to produce efficient code. The algorithm also takes account of downstream compiler passes---specifically software pipelining and buffer allocation---and it models the compiler's ability to fuse kernels. The latter is important because the compiler may not be able to fuse arbitrary collections of kernels. This thesis also introduces a static queue sizing algorithm. This algorithm is important when memory is distributed, especially when local stores are small. The algorithm takes account of latencies and variations in computation time, and is constrained by the sizes of the local memories. The second part of this thesis is concerned with dynamic scheduling of stream programs. First, it investigates the performance of known online, non-preemptive, non-clairvoyant dynamic schedulers. Second, it proposes two dynamic schedulers for stream programs. The first is specifically for one-dimensional stream programs. The second is more general: it does not need to be told the stream graph, but it has slightly larger overhead. This thesis also introduces some support tools related to stream programming. StarssCheck is a debugging tool, based on Valgrind, for the StarSs task-parallel programming language. It generates a warning whenever the program's behaviour contradicts a pragma annotation. Such behaviour could otherwise lead to exceptions or race conditions. StreamIt to OmpSs is a tool to convert a streaming program in the StreamIt language into a dynamically scheduled task based program using StarSs.
Totes les empreses de semiconductors produeixen actualment multi-cores. Mòbils,PCs, portàtils, i dispositius mòbils d’Internet necessitaran programari quefaci servir eficientment aquests cores. Escriure programari paral·lel d’altrendiment és difícil, laboriós i propens a errors, incrementant tant el tempsde llançament al mercat com el cost. El programari té una vida més llarga queel maquinari; típicament pren més temps desenvolupar nou programi que noumaquinari, i el programari ja existent pot perdurar molt temps, durant el qualel nombre de cores dels sistemes incrementarà. La productivitat dedesenvolupament i manteniment millorarà si el paral·lelisme i els detallstècnics són gestionats per la màquina, mentre el programador raona sobre elconjunt de l’aplicació.El programari paral·lel hauria de ser escrit en llenguatges específics deldomini. Aquests llenguatges extrauen paral·lelisme implícit, el qual és ocultatper un llenguatge seqüencial com C. Quan l’assignació de memòria i lesestructures de control són gestionades pel compilador, l’estructura iorganització de dades del programi poden ser modificades de manera segura ifiable per les transformacions d’alt nivell del compilador.Un dels dominis de l’aplicació importants és el que consta dels programes destream; aquest programes són estructurats com a nuclis independents queinteractuen només a través de canals d’un sol sentit, anomenats streams. Laprogramació de streams no és aplicable a tots els programes, però sorgeix deforma natural en la codificació i descodificació d’àudio i vídeo, gràfics 3D, iprocessament de senyals digitals. Aquesta representació permet transformacionsd’alt nivell, fins i tot descomposició i fusió de nucli.Aquesta tesi desenvolupa noves tècniques de compilació i sistemes en tempsd’execució per a programació de streams. La primera part d’aquesta tesi esfocalitza amb un compilador de streams de planificació estàtica. Presenta unnou algorisme de partició estàtica, que determina quins nuclis han de serfusionats, per tal d’equilibrar la càrrega en els processadors i en lesinterconnexions. Un bon algorisme de particionat és fonamental per tal de queel compilador produeixi codi eficient. L’algorisme també té en compte elspassos de compilació subseqüents---específicament software pipelining il’arranjament de buffers---i modela la capacitat del compilador per fusionarnuclis. Aquesta tesi també presenta un algorisme estàtic de redimensionament de cues.Aquest algorisme és important quan la memòria és distribuïda, especialment quanles memòries locals són petites. L’algorisme té en compte latències ivariacions en els temps de càlcul, i considera el límit imposat per la mida deles memòries locals.La segona part d’aquesta tesi es centralitza en la planificació dinàmica deprogrames de streams. En primer lloc, investiga el rendiment dels planificadorsdinàmics online, non-preemptive i non-clairvoyant. En segon lloc, proposa dosplanificadors dinàmics per programes de stream. El primer és específicament pera programes de streams unidimensionals. El segon és més general: no necessitael graf de streams, però els overheads són una mica més grans.Aquesta tesi també presenta un conjunt d’eines de suport relacionades amb laprogramació de streams. StarssCheck és una eina de depuració, que és basa enValgrind, per StarSs, un llenguatge de programació paral·lela basat en tasques.Aquesta eina genera un avís cada vegada que el comportament del programa estàen contradicció amb una anotació pragma. Aquest comportament d’una altra manerapodria causar excepcions o situacions de competició. StreamIt to OmpSs és unaeina per convertir un programa de streams codificat en el llenguatge StreamIt aun programa de tasques en StarSs planificat de forma dinàmica.

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50

Carpenter, Paul. "Running stream-like programs on heterogeneous multi-core systems." Doctoral thesis, Universitat Politècnica de Catalunya, 2011. http://hdl.handle.net/10803/84186.

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Abstract:

All major semiconductor companies are now shipping multi-cores. Phones, PCs, laptops, and mobile internet devices will all require software that can make effective use of these cores. Writing high-performance parallel software is difficult, time-consuming and error prone, increasing both time-to-market and cost. Software outlives hardware; it typically takes longer to develop new software than hardware, and legacy software tends to survive for a long time, during which the number of cores per system will increase. Development and maintenance productivity will be improved if parallelism and technical details are managed by the machine, while the programmer reasons about the application as a whole. Parallel software should be written using domain-specific high-level languages or extensions. These languages reveal implicit parallelism, which would be obscured by a sequential language such as C. When memory allocation and program control are managed by the compiler, the program's structure and data layout can be safely and reliably modified by high-level compiler transformations. One important application domain contains so-called stream programs, which are structured as independent kernels interacting only through one-way channels, called streams. Stream programming is not applicable to all programs, but it arises naturally in audio and video encode and decode, 3D graphics, and digital signal processing. This representation enables high-level transformations, including kernel unrolling and kernel fusion. This thesis develops new compiler and run-time techniques for stream programming. The first part of the thesis is concerned with a statically scheduled stream compiler. It introduces a new static partitioning algorithm, which determines which kernels should be fused, in order to balance the loads on the processors and interconnects. A good partitioning algorithm is crucial if the compiler is to produce efficient code. The algorithm also takes account of downstream compiler passes---specifically software pipelining and buffer allocation---and it models the compiler's ability to fuse kernels. The latter is important because the compiler may not be able to fuse arbitrary collections of kernels. This thesis also introduces a static queue sizing algorithm. This algorithm is important when memory is distributed, especially when local stores are small. The algorithm takes account of latencies and variations in computation time, and is constrained by the sizes of the local memories. The second part of this thesis is concerned with dynamic scheduling of stream programs. First, it investigates the performance of known online, non-preemptive, non-clairvoyant dynamic schedulers. Second, it proposes two dynamic schedulers for stream programs. The first is specifically for one-dimensional stream programs. The second is more general: it does not need to be told the stream graph, but it has slightly larger overhead. This thesis also introduces some support tools related to stream programming. StarssCheck is a debugging tool, based on Valgrind, for the StarSs task-parallel programming language. It generates a warning whenever the program's behaviour contradicts a pragma annotation. Such behaviour could otherwise lead to exceptions or race conditions. StreamIt to OmpSs is a tool to convert a streaming program in the StreamIt language into a dynamically scheduled task based program using StarSs.
Totes les empreses de semiconductors produeixen actualment multi-cores. Mòbils,PCs, portàtils, i dispositius mòbils d’Internet necessitaran programari quefaci servir eficientment aquests cores. Escriure programari paral·lel d’altrendiment és difícil, laboriós i propens a errors, incrementant tant el tempsde llançament al mercat com el cost. El programari té una vida més llarga queel maquinari; típicament pren més temps desenvolupar nou programi que noumaquinari, i el programari ja existent pot perdurar molt temps, durant el qualel nombre de cores dels sistemes incrementarà. La productivitat dedesenvolupament i manteniment millorarà si el paral·lelisme i els detallstècnics són gestionats per la màquina, mentre el programador raona sobre elconjunt de l’aplicació.El programari paral·lel hauria de ser escrit en llenguatges específics deldomini. Aquests llenguatges extrauen paral·lelisme implícit, el qual és ocultatper un llenguatge seqüencial com C. Quan l’assignació de memòria i lesestructures de control són gestionades pel compilador, l’estructura iorganització de dades del programi poden ser modificades de manera segura ifiable per les transformacions d’alt nivell del compilador.Un dels dominis de l’aplicació importants és el que consta dels programes destream; aquest programes són estructurats com a nuclis independents queinteractuen només a través de canals d’un sol sentit, anomenats streams. Laprogramació de streams no és aplicable a tots els programes, però sorgeix deforma natural en la codificació i descodificació d’àudio i vídeo, gràfics 3D, iprocessament de senyals digitals. Aquesta representació permet transformacionsd’alt nivell, fins i tot descomposició i fusió de nucli.Aquesta tesi desenvolupa noves tècniques de compilació i sistemes en tempsd’execució per a programació de streams. La primera part d’aquesta tesi esfocalitza amb un compilador de streams de planificació estàtica. Presenta unnou algorisme de partició estàtica, que determina quins nuclis han de serfusionats, per tal d’equilibrar la càrrega en els processadors i en lesinterconnexions. Un bon algorisme de particionat és fonamental per tal de queel compilador produeixi codi eficient. L’algorisme també té en compte elspassos de compilació subseqüents---específicament software pipelining il’arranjament de buffers---i modela la capacitat del compilador per fusionarnuclis. Aquesta tesi també presenta un algorisme estàtic de redimensionament de cues.Aquest algorisme és important quan la memòria és distribuïda, especialment quanles memòries locals són petites. L’algorisme té en compte latències ivariacions en els temps de càlcul, i considera el límit imposat per la mida deles memòries locals.La segona part d’aquesta tesi es centralitza en la planificació dinàmica deprogrames de streams. En primer lloc, investiga el rendiment dels planificadorsdinàmics online, non-preemptive i non-clairvoyant. En segon lloc, proposa dosplanificadors dinàmics per programes de stream. El primer és específicament pera programes de streams unidimensionals. El segon és més general: no necessitael graf de streams, però els overheads són una mica més grans.Aquesta tesi també presenta un conjunt d’eines de suport relacionades amb laprogramació de streams. StarssCheck és una eina de depuració, que és basa enValgrind, per StarSs, un llenguatge de programació paral·lela basat en tasques.Aquesta eina genera un avís cada vegada que el comportament del programa estàen contradicció amb una anotació pragma. Aquest comportament d’una altra manerapodria causar excepcions o situacions de competició. StreamIt to OmpSs és unaeina per convertir un programa de streams codificat en el llenguatge StreamIt aun programa de tasques en StarSs planificat de forma dinàmica.

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Dissertations / Theses on the topic 'OMPs'

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