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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Overcoming Sin: Comparing Dante’s Inferno and the New Testament to Cormac McCarthy’s Outer Dark and Child of God

Hanson, Tammy S 13 May 2016 (has links)
There are many textual and thematic similarities between Dante’s Inferno and Cormac McCarthy’s Outer Dark. There are also significant textual similarities between the New Testament and McCarthy’s third novel, Child of God. Juxtaposing Outer Dark and Child of God to Inferno and the New Testament, respectively, suggests a common trope that redemption requires characters’ name and repent of sin.
92

Ecopolítica: derivas do espaço sideral

Siqueira, Leandro Alberto de Paiva 16 October 2015 (has links)
Made available in DSpace on 2016-04-26T14:55:43Z (GMT). No. of bitstreams: 1 Leandro Alberto de Paiva Siqueira.pdf: 11537130 bytes, checksum: a8323afe02aa8163c883de8083f56f2e (MD5) Previous issue date: 2015-10-16 / Fundação de Amparo a Pesquisa do Estado de São Paulo / Beginning with the second half of the twentieth century, rockets, satellites, probes, spacecraft, and space stations have allowed for the occupation of Earth's orbit and achievement of space travel to nearby locations to Earth. Driven by the arms race, space technology projected war and politics into orbit, establishing the first planetary monitoring systems, initially used to spy on missiles. Interested in contemporaneity, this thesis aims to contribute to the study of societies of control showing their outer space proveniences and stressing the importance of the space event for the configuration of exposed power relations belonging to such societies. Besides being taken from its ascendant perspective, in the sense of abandoning the planet, the outer space event should also be analyzed according to its downward movement, in other words, taking into account its drifts, especially the spin-offs that it produces and that can not be reduced to products or socio-economic benefits, but also imply political resizing of the governing of the planet and life. Among the political spin-offs arising from the outer space event we focus on the emergence of the planet-body, which becomes the aim of ecopolitics investment for control societies. The outer space event was decisive to the point that societies of control configured an intelligibility of Earth which understands it as a planet that is fragile when managed. From the administration of state violence to the management of climate change, we present the functioning of a planetary governmentality which seeks to guarantee the safety of transterritorial flows established with the expansion of neoliberalism also on a global scale / A partir da segunda metade do século XX, foguetes, satélites, sondas, espaçonaves e estações espaciais permitiram a ocupação da órbita terrestre e a realização de viagens espaciais a localidades próximas da Terra. Impulsionadas pela corrida armamentista, as tecnologias espaciais projetaram a guerra e a política para a órbita, instaurando os primeiros sistemas planetários de monitoramento, incialmente utilizados para se espionar mísseis. Interessada na contemporaneidade, esta tese pretende contribuir para os estudos sobre as sociedades de controle evidenciando suas procedências siderais e ressaltando a importância do acontecimento espacial para a configuração das relações de poder a céu aberto próprias a estas sociedades. Além de ser tomado em sua perspectiva ascendente, no sentido de abandonar o planeta, o acontecimento espaço sideral também deve ser analisado segundo o seu movimento descendente, ou seja, levando em consideração suas derivas, principalmente os spin-offs (derivações) que produz e que não se reduzem a produtos ou a benefícios socioeconômicos, mas também implicam em redimensionamentos políticos do governo do planeta e da vida. Dentre os spin-offs políticos que derivam do acontecimento sideral destacamos nesta tese a emergência do corpo-planeta, que se torna o alvo de investimentos da ecopolítica das sociedades de controle. O acontecimento sideral foi decisivo para que as sociedades de controle configurassem uma inteligibilidade da Terra que a toma como um frágil planeta a ser gerenciado. Da administração dos estados de violência à gestão das mudanças climáticas, apresentamos neste trabalho o funcionamento de uma governamentalidade planetária que procura garantir a segurança dos fluxos transterritoriais instaurados com a expansão do neoliberalismo também em escala planetária
93

Strategická analýza Nemocnice Pelhřimov, p.o. / Strategic Analysis of Pelhřimov Hospital

Stráská, Alena January 2011 (has links)
The diploma thesis deals with the Strategic analysis of Pelhřimov hospital, allowance organization. The health-care facility, which is established by Vysočina region, is situated in dynamic environment. In the catchment area, which is defined by the district, the researched subject adopts the dominating position on the market. Doubtless, the strong points of Pelhřimov hospital are the human capital and the quality of provided health care. On the other hand, the weak points are economic situation of the hospital and insufficient marketing activities. On the basis of the determinated drawbacks, which come out of the internal and external analysis, the recommendation in the form of action plan is stated at the end of the thesis.
94

Variations and trends in the sensitivity of machair soils and coastal landforms to erosion, South Uist, Outer Hebrides

Young, Elizabeth January 2015 (has links)
The machair is a coastal grassland system found only in parts of northern and western Scotland and Ireland. Despite its limited geographic distribution, machair landscapes have high ecological, geomorphological, and cultural significance, as recognised by numerous conservation designations and legislation. In January 2005 a severe storm caused extensive damage in the Outer Hebrides, drawing attention to the sensitivity of the machair coast to erosion. The aim of this research was to investigate variations and trends in the sensitivity of three field sites within the South Uist machair to soil and coastal erosion, and to interpret measured change alongside analysis of historic climate data. Two of the sites selected, Cille Pheadair and Staoinebrig, experienced some of the most dramatic geomorphological changes associated with the 2005 storm, while the third site, Milton, appeared to be more resistant to change. A combination of fieldwork, laboratory tests, and archive work was used to obtain and analyse information about sediment budgets, shoreline indicator change, and sediment erodibility, along with contextual climatic information. A key result of this work is the provision of a detailed framework of short-medium term cyclical changes and fluctuations in the coastal change, which provides a context for interpreting and responding to longer term trends in erosion and/or accretion. Results indicated high spatial and temporal variability in the erodibility of machair soils and landforms, with no clear relationship between climatic factors and rates of erosion. Considerable short-term variations in beach volume and the position of dynamic shoreline indicators caution against the relaibility of using ‘snap-shot’ historic datasets to infer long-term rates of change. It is proposed that the machair landscape currently functions in a state of highly dynamic equilibrium, which has been maintained over the last ~130 years. While storm events such as the January 2005 storm have locally dramatic consequences, they do not appear to have disrupted the overally physical and ecological functions of the system. This contribution is particularly timely given current concerns for the future of the machair landscape under predicted sea-level and climate change scenarios, and the potential for inappropriate hard-engineering responses to the perceived risk.
95

Novel Role of Pseudomonas Aeruginosa LptD Operon

Pandey, Sundar 29 June 2018 (has links)
Pseudomonas aeruginosais an opportunistic pathogen that infects cystic fibrosis (CF) patients contributing to their high morbidity and mortality. P. aeruginosaundergoes a phenotypic conversion in the CF lung, from nonmucoid to mucoid, by constitutively producing a polysaccharide called alginate. These mucoid strains often revert to nonmucoid in vitrodue to second-site suppressor mutations. We hypothesized that mapping these mutations would lead to the identification of novel genes involved in alginate production. In a previous study, a mucoid strain, PDO300 (PAOmucA22), was used to isolate suppressors of alginate phenotype (sap). One of the uncharacterized nonmucoid revertants, sap27, is the subject of this study. The mucoid phenotype in sap27was restored by pMO012217 from a minimal tiling path cosmid library. The cosmid pMO012217 harbors 18 P. aeruginosaopen reading frames (ORF). The cosmid was mutagenized with a transposon to map the contributing gene. It was mapped tolptD(PA0595) encoding lipopolysaccharide transport protein. E. coliLptD transports lipopolysaccharide to the outer leaflet of the outer membrane. The Alg+phenotype was restored upon complementation with P. aeruginosa lptDalone, suggesting that sap27likely harbor a chromosomal mutation inlptD. Sequencing analysis of sap27showed the presence of a mutation not in lptDbut in algO, which encodes a periplasmic protease protein. This suggests LptD is able to bypass analgO mutation by positively regulating alginate production. The lptD is a part of a three-gene operon lptD-surA-pdxA. SurA is an essential protein for survival in starvation and a major chaperone protein for all outer membrane proteins and PdxA is a NAD-dependent dehydrogenase and is involved in the vitamin B6biosynthetic pathway. Pyridoxal 5’-phosphate (PLP) is the active form of vitamin B6.P. aeruginosagrown in a media supplemented with PLP increased production of pyocyanin, a virulence factor. The PLP and aromatic amino acids are synthesized from a common precursor chorismic acid. We demonstrated an increase in pyocyanin production when the bacteria were cultured supplemented by the aromatic amino acids phenylalanine. We concluded that the lptDoperon plays a role in the P. aeruginosavirulence by regulating alginate and pyocyanin production.
96

A tale of two RLPAs : studies of cell division in Escherichia coli and Pseudomonas aeruginosa

Jorgenson, Matthew Allan 01 July 2014 (has links)
Rare lipoprotein A (RlpA) has been studied previously only in Escherichia coli, where it localizes to the septal ring and scattered foci along the lateral wall, but mutants have no phenotypic change. In this thesis, we show rlpA mutants of Pseudomonas aeruginosa form chains of short, fat cells when grown in media of low osmotic strength. These morphological defects indicate RlpA is needed for efficient separation of daughter cells and maintenance of rod shape. Analysis of peptidoglycan sacculi from a ΔrlpA mutant revealed increased tetra and hexasaccharides that lack stem peptides (hereafter called "naked glycans"). Incubation of these sacculi with purified RlpA resulted in release of naked glycans containing 1,6-anhydro N-acetylmuramic acid ends. RlpA did not degrade sacculi from wild-type cells unless the sacculi were subjected to a limited digestion with an amidase to remove some of the stem peptides. Collectively, these findings indicate RlpA is a lytic transglycosylase with a strong preference for naked glycan strands. We propose that RlpA activity is regulated in vivo by substrate availability, and that amidases and RlpA work in tandem to degrade peptidoglycan in the division septum and lateral wall. Our discovery that RlpA from P. aeruginosa is a lytic transglycosylase motivated us to reinvestigate RlpA from E. coli. We confirmed predictions that RlpA of E. coli is an outer membrane protein and determined its abundance to be about 600 molecules per cell. However, multiple efforts to demonstrate that E. coli RlpA is a lytic transglycosylase were unsuccessful and the function of this protein in E. coli remains obscure.
97

The Underwater Piano: A Resonance Theory of Cochlear Mechanics

Bell, James Andrew, andrew.bell@anu.edu.au January 2006 (has links)
This thesis takes a fresh approach to cochlear mechanics. Over the last quarter of a century, we have learnt that the cochlea is active and highly tuned, observations suggesting that something may be resonating. Rather than accepting the standard traveling wave interpretation, here I investigate whether a resonance theory of some kind can be applied to this remarkable behaviour.¶ A historical survey of resonance theories is first conducted, and advantages and drawbacks examined. A corresponding look at the traveling wave theory includes a listing of its short-comings.¶ A new model of the cochlea is put forward that exhibits inherently high tuning. The surface acoustic wave (SAW) model suggests that the three rows of outer hair cells (OHCs) interact in a similar way to the interdigital transducers of an electronic SAW device. Analytic equations are developed to describe the conjectured interactions between rows of active OHCs in which each cell is treated as a point source of expanding wavefronts. Motion of a cell launches a wave that is sensed by the stereocilia of neighbouring cells, producing positive feedback. Numerical calculations confirm that this arrangement provides sharp tuning when the feedback gain is set just below oscillation threshold.¶ A major requirement of the SAW model is that the waves carrying the feedback have slow speed (5-200 mm/s) and high dispersion. A wave type with the required properties is identified - a symmetric Lloyd-Redwood wave (or squirting wave) - and the physical properties of the organ of Corti are shown to well match those required by theory.¶ The squirting wave mechanism may provide a second filter for a primary traveling wave stimulus, or stand-alone tuning in a pure resonance model. In both, cyclic activity of squirting waves leads to standing waves, and this provides a physical rendering of the cochlear amplifier. In keeping with pure resonance, this thesis proposes that OHCs react to the fast pressure wave rather than to bending of stereocilia induced by a traveling wave. Investigation of literature on OHC ultrastructure reveals anatomical features consistent with them being pressure detectors: they possess a cuticular pore (a small compliant spot in an otherwise rigid cell body) and a spherical body within (Hensens body) that could be compressible. I conclude that OHCs are dual detectors, sensing displacement at high intensities and pressure at low. Thus, the conventional traveling wave could operate at high levels and resonance at levels dominated by the cochlear amplifier. ¶ The latter picture accords with the description due to Gold (1987) that the cochlea is an ‘underwater piano’ - a bank of strings that are highly tuned despite immersion in liquid.¶ An autocorrelation analysis of the distinctive outer hair cell geometry shows trends that support the SAW model. In particular, it explains why maximum distortion occurs at a ratio of the two primaries of about 1.2. This ratio also produces near-integer ratios in certain hair-cell alignments, suggesting that music may have a cochlear basis.¶ The thesis concludes with an evaluation and proposals to experimentally test its validity.
98

Design of an Analog VLSI Cochlea

Shiraishi, Hisako January 2003 (has links)
The cochlea is an organ which extracts frequency information from the input sound wave. It also produces nerve signals, which are further analysed by the brain and ultimately lead to perception of the sound. An existing model of the cochlea by Fragni`ere is first analysed by simulation. This passive model is found to have the properties that the living cochlea does in terms of the frequency response. An analog VLSI circuit implementation of this cochlear model in CMOS weak inversion is proposed, using log-domain filters in current domain. It is fabricated on a chip and a measurement of a basilar membrane section is performed. The measurement shows a reasonable agreement to the model. However, the circuit is found to have a problem related to transistor mismatch, causing different behaviour in identical circuit blocks. An active cochlear model is proposed to overcome this problem. The model incorporates the effect of the outer hair cells in the living cochlea, which controls the quality factor of the basilar membrane filters. The outer hair cells are incorporated as an extra voltage source in series with the basilar membrane resonator. Its value saturates as the input signal becomes larger, making the behaviour rather closer to that of a passive model. The simulation results show this nonlinear phenomenon, which is also seen in the living cochlea. The contribution of this thesis is summarised as follows: a) the first CMOS weak inversion current domain basilar membrane resonator is designed and fabricated, and b) the first active two-dimensional cochlear model for analog VLSI implementation is developed.
99

Functional characterization of the small antisense RNA MicA in Escherichia coli

Udekwu, Klas Ifeanyi January 2007 (has links)
<p>The Escherichia coli small RNA (sRNA) MicA was identified recently in a genomewide search for sRNAs. It is encoded between the genes <i>gshA</i> and <i>luxS</i> in E. coli and its close relatives. The function of sRNAs in bacteria is generally believed to be in maintenance of homeostasis via stress-induced modulation of gene expression. Our studies on MicA have been aimed at attributing function(s) to this molecule.</p><p>We carried out high throughput assays aimed at identifying genes that are differentially regulated upon knocking out or overexpressing MicA. Among the protein candidates identified was the outer membrane protein, OmpA. Subsequent analysis allowed us to show this regulation to be antisense in nature with MicA binding within the translation initiation region of <i>ompA</i> mRNA. Furthermore, blocking the ribosome from loading caused a translational decoupling that instigates degradation of the mRNA. The regulation was apparent in early stationary phase and seen to be dependent on the RNA chaperone Hfq. </p><p>We went on to characterize the regulation of MicA, looking at its own transcription. Testing various stress conditions, we were able to identify putative promoter elements that we confirmed using transcriptional fusions. The results showed MicA to be dependent on the extracytoplasmic function ECF sigma E (σ<sup>E</sup>) and could not detect MicA in mutants deleted for this factor.</p><p>Lastly, we identified an additional target for MicA being the adjacently encoded <i>luxS</i> mRNA. The LuxS protein is essential for the synthesis of the quorum sensing AI-2 molecule. Transcription of the <i>luxS </i>mRNA is commences within the <i>gshA</i> gene, on the other side of MicA coding region. We were able to show that MicA interacts with <i>luxS </i>mRNA and is recognized by RNase III which processes this complex leading to a shorter <i>luxS</i> mRNA isoform. The significance of this processing event is as yet undetermined. Our data elucidated a new promoter driving transcription of <i>luxS,</i> and we demonstrated this promoter to be stationary phase responsive.</p><p>In summary, the work presented here characterizes the sRNA MicA as a dual regulatory sRNA molecule, moonlighting between its cis-encoded target and its trans-encoded target. .</p>
100

Innate and Adaptive Immunity in Murine Neonates Infected with the Intestinal Pathogen Yersinia enterocolitica

Echeverry, Andrea 22 September 2009 (has links)
Neonates are generally thought to be more likely to suffer from gastrointestinal disease, owing in part to diminished immune cell function. To gain insight into the development of mucosal immune responses during early life, we developed a model of orogastric infection with the Gram-negative bacterium Yersinia enterocolitica using murine neonates. Remarkably, neonatal mice of either the BALB/c or C57BL/6 mouse strains showed markedly enhanced survival after infection compared to adult mice. Both innate and adaptive immune components appear to contribute to this phenomenon. First, the increased resistance of neonates coincided with containment of the bacteria in the intestinal tissue with low dissemination into the spleen and liver. In contrast, the bacteria readily disseminated to the peripheral tissues in adult mice. Flow cytometric and histological studies revealed increased levels of neutrophils and macrophages in the neonatal mesenteric lymph nodes (MLN) compared to adult mice. Similar results were obtained using two different high virulence Y. enterocolitica strains. The rapid mobilization of innate cells sequestered the bacteria to the intestinal tissue, since in vivo neutrophil depletion led to efficient dissemination of Y. enterocolitica to the spleen and liver of neonates. Together, these results support the hypothesis that the neonatal intestinal immune system is competent to mount a strong antibacterial response by rapidly mobilizing innate phagocytes and thereby confining the bacterial infection to the gut, resulting in a high level of resistance. Second, we have also demonstrated that the adaptive immune system was mobilized during primary and secondary infection with this pathogen and that some of these factors may contribute to the enhanced resistance of neonatal mice to infection. Primary infection in neonates led to increased levels of antigen presenting cells, B and T cells with an activated phenotype in the MLN. MLN CD4+ Th cells from infected neonates were found to produce greater levels of IFN-gamma and IL-17A, compared to CD4+ Th cells from adult mice. These Th responses are likely to be functionally significant because neonatal mice deficient in CD4+ T cells were found to be more susceptible than adult mice to primary infection. CD4+ T cells adoptively transferred into CD4 deficient mice rescued the majority of mice from lethal infection and led to the production of IFN-gamma and IL-17A by MLN cells. In addition, primary T cell-dependent IgG1 and IgG2a serum antibodies specific for the Yersinia immunogen LcrV were increased compared to adult mice, and the absence of B cells partially increased the susceptibility of neonatal mice to primary infection. During secondary infection, however, neonatal and adult mice mounted quantitatively and qualitatively similar Yersinia-specific memory antibody responses, demonstrating that infection with Y. enterocolitica promotes mature B cell responses in neonatal mice. Finally, primed neonatal and adult mice were protected from colonization of the Peyer's patches, weight loss and mortality after a lethal infection in adulthood, demonstrating the development of long-lived protective memory responses at the intestinal interface. Together, these results indicate that both B and T cell responses, in particular Th1 and Th17 associated immunity, are important for the development of long lasting immunity to this pathogen in early life. Third, infection of neonatal mice with a Y. enterocolitica strain deleted of the anti-inflammatory protein YopP led to massive infiltration and/or accumulation of innate phagocytes in the intestine and MLN. This effect was not detectable in infected adult mice. Thus, we have identified a novel negative regulator of intestinal inflammation which might be valuable in preventing or ameliorating inflammatory conditions. This model system has revealed the unprecedented potential of neonatal mice to develop protective inflammatory innate and adaptive immunity at mucosal surfaces. The combined results presented here demonstrate that neonatal mice may be well equipped to mount robust innate and adaptive intestinal inflammatory responses that are highly protective toward Y. enterocolitica. These findings have implications for understanding how pediatric intestinal adaptive immune responses develop in response to naturally occurring gastroenteric pathogens and offer a new biological platform for development of vaccines aimed at improving mucosal and systemic immunity in early life.

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