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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.
61

Something's happening on ABC : queerly reevaluating Twin Peaks and My So-Called Life

Kruger-Robbins, Benjamin 14 October 2014 (has links)
This research reconsiders two ABC programs from the early 1990s, Twin Peaks and My So-Called Life, through the frames of queer-theory based textual analysis, press discourse, and fan reception. I begin by arguing that both programs, which emerged in concert with the solidification of queer studies as an academic field, exist as televisual oddities that provided a temporary space for the exploration of queer subjectivities in primetime; this analysis also invokes the non-normative positioning of showrunners David Lynch and Winnie Holzman based on their previous and subsequent work. Secondly, I posit popular press receptions/retrospectives as undermining the queer centrality of both programs by adhering to heteronormative frameworks such as “quality television.” Lastly, I discuss fan reclamations of both programs through slash fiction and collaborative web forums as illuminating the intrinsic queerness of Twin Peaks and My So-Called Life lost through dominant press narratives. / text
62

Key aspects of the structural design of small SWATH ships

Loscombe, Peter Robin January 1989 (has links)
No description available.
63

Origins and structure of social and political attitudes : insights from personality system theory and behavioural genetics

Lewis, Gary J. January 2012 (has links)
People differ, often strikingly, in their views on desired social structures and processes. For example, while some value ethnic diversity in their society, others believe non-indigenous individuals (whatever that might mean) should be repatriated to their land of origin. Similarly, whereas some believe religion should play no role in determining social policy, others strongly advocate the importance of living according to religious scripture, including at a social level. This variation in attitudes, and its implication for societal cohesion, has made research on the origins of social and political attitudes of enduring interest to psychologists, sociologists, political scientists, among many others. The goal of the current thesis was to extend work in this literature in two key ways: Firstly, I examined whether political attitudes can be understood within a personality system model. This work addresses previous mixed results on the links of basic personality traits to political conservatism. In Chapter 3, I test predictions from this model; namely, that direct influences on political behaviour flow from moral values, with personality mostly acting indirectly via these moral values, rather than directly affecting political attitudes. Findings from two studies (published as Lewis & Bates, 2011a) supported these predictions suggesting that the new model helps explain inconsistencies in previous research attempting to link personality to political orientation that have not included the intermediary level of values. Secondly, I examined the genetic architecture of social attitudes constructs in three separate studies. Chapter 4 addressed whether in-group favouritism reflects heritable effects, and, secondly, whether race-favouritism was accounted for broad or specific genetic effects. Results indicated that a common biological mechanism exists facilitating generalised favouritism, with evidence for additional genetic effects specific to each form of group favouritism. These findings(published as Lewis & Bates, 2010) suggest that (at least) at the genetic level, race favouritism is multiply determined. In Chapter 5, I examined whether prosocial obligations across the domains of welfare, work, and civic obligation share a common genetic basis, or reflect specific heritable components (published as Lewis & Bates, 2011b). In females, results indicated the existence of a common heritable factor underlying each of these prosocial obligations. In males, a prosocial factor was also observed; familial effects (genetic and shared-environment effects were indistinguishable) influenced this general mechanism. At the domain-specific level, modest genetic effects were observed in females for civic and work obligations, with shared environment effects influencing welfare obligations. In males, genetic influences were observed for welfare obligation, with unique-environments affecting work and civic duty. Finally, in Chapter 6, I present work examining the genetic architecture of religious belief. Although genetic factors are known to influence strength of religious belief, the psychological mechanism(s) through which this biological influence is manifest are presently unknown. Two non-theological constructs – 1) need for community integration and 2) need for existential certainty – were hypothesised to account for the genetic effects on religiosity. The results supported this hypothesis, with genetic influences on these traits wholly accounting for the heritable basis of religiosity, suggesting that religion “re-uses” systems involved in meeting both social and existential needs.
64

Investigation of Escherichia coli Tat (Twin arginine translocase) transport in vitro

Yong, Shee Chien January 2011 (has links)
The Twin arginine translocase (Tat) system catalyzes movement of folded proteins across the cytoplasmic membrane of bacteria and the thylakoid membrane of plant chloroplasts. This transport process requires energy in the form of the transmembrane proton motive force (PMF). The Tat system can be studied in vitro using inner membrane vesicles (IMVs) from E. coli overproducing the Tat components, TatA, TatB and TatC. However, the transport efficiencies of current in vitro Tat transport assays are low. In this work, current in vitro Tat transport assays were compared and parameters that affect transport efficiencies were identified. Mild French press treatment of IMVs resulted in larger IMVs with higher transport efficiencies. Chloride ions were shown to inhibit Tat transport in vitro. Generation of a PMF by the activity of ATP synthase gave higher transport efficiencies than generating a PMF by NADH respiration. This understanding was applied to develop an optimized in vitro Tat transport assay that showed a higher transport efficiency than currently published methods. Fluorescently labelled Tat substrates were developed to allow quantitative analysis of Tat transport. The transport of the purified native Tat substrate, CueO into IMVs was characterized using the optimized in vitro Tat transport assay. It was shown that the proton concentration (ΔpH) component of the PMF was sufficient to support Tat transport in vitro. It was observed that transport of CueO ceased in a time-dependent manner in the in vitro Tat transport assays. This loss of transport efficiency could be due, at least in part, to the presence of a PMF since transport efficiency was reduced when IMVs were pre-energized. Substrates for future in vitro single molecule fluorescence microscopy studies of the Tat transport were developed in this work. One of the substrates is fluorescently labelled CueO. The second substrate is the native Tat substrate alkaline phosphatase PhoX from Vibrio fischeri which was able to cleave the fluorogenic compound AttoPhos® and can thus be used as an enzymatic reporter of Tat transport. The structure of a native Tat substrate from Pseudomonas fluorescens, PhoX, was solved by X-ray crystallography at a resolution of 1.4Å. PhoX is a monomeric six blade β propeller with two α-helical bundle subdomains. PhoX was shown to have optimum activity at pH8.0. PhoX has a novel catalytic site which requires two Fe<sup>3+</sup> (including a Cys-coordinated Fe<sup>3+</sup>) and three Ca<sup>2+</sup> as cofactors. Mutagenesis studies showed that all the metal ions are required for the integrity of the active site. Co-crystallization of PhoX with vanadate, an inhibitor of PhoX which mimics the transition state, showed that hydrolysis of phosphomonoesters does not involve formation of a covalent phosphoenzyme intermediate. Instead, dephosphorylation of substrates is proposed to occur via a SN2 reaction with OH- as the attacking nucleophile.
65

Heritability of Autoantibody Levels in a Twin Population

Rastogi, Amal 29 June 2009 (has links)
AIM: This study aims to determine what portion of specific autoantibody phenotypes are genetically determined by using a twin model. METHODS: This study specifically examines Anti-Ro(SSA), Anti-La (SSB), Anti-Sn/RNP, Anti-Sm, Anti-Jo-1, Anti-Scl-70, Anti-Tg & Anti-TPO, Anti-dsDNA, Anti-PS, and Anti-cardiolipin antibodies for their heritability. This study examined 104 same-sex adult twins (66 monozygous, 38 dizygous) for the above mentioned autoantibody values. The serum autoantibody values in each subject were quantified using automated ELISA. Descriptive statistics including, distributions, quantiles, and moments were calculated by zygosity for continuous antibody values, subject ages, gender, race and smoking status. Categorical antibody levels were used to determine twin pair concordance rates. Continuous and rank ordered autoantibody values were used to determine the presence and portion of a genetic component. To evaluate how strongly the antibody values in each twin group resembled each other, the intraclass correlation was calculated for each antibody by zygosity. The genetic variances, environmental variances, and heritability were estimated using path models with maximum likelihood estimation techniques. The phenotypic variance was modeled as a linear function of underlying additive genetic (A), dominant genetic (D), common environmental (C), and random environmental (E) effects. RESULTS: Several antibodies demonstrated a genetic component in our study population. Anti-cardiolipin had a genetic component with an estimated 69% heritability. Anti-dsDNA yielded a genetic component with a heritability estimate of 55-62%. Anti-Jo-1 presented a genetic component with the heritability estimate to be 41-51%. Anti-SCL-70 demonstrated a genetic component with a heritability estimate of 42-59%. Anti-PL had a genetic component with a heritability estimate of 52-54%. Several antibodies did not have a measurable genetic component. These included anti-Sm, anti-Ro(SSA), anti-La(SSB), anti-sn/RNP, anti-Tg, and anti-TPO. Some possibilities for the lack of a measureable genetic component may be due to the limited number of discordant twin pairs and/or the small number of subjects with higher levels of antibodies. CONCLUSION: The results of this study suggest several clinically relevant markers of auto-immunity may be partially genetically determined. These include: anti-cardiolipin, anti-dsDNA, anti-Jo-1, anti-SCL-70, and anti-phospholid.
66

Etude de la bioraffinerie des plantes vertes : Application au fractionnement des protéines de luzerne par extrusion bi-vis et chromatographie hydrophobe / Green crop biorefinery evaluation : alfalfa protein fractionation using twin-screw extrusion and hydrophobic chromatography

Colas, Dorothée 29 March 2012 (has links)
La luzerne est une plante fourragère, de la famille des Fabacées, largement cultivée en France du fait de sa richesse en protéines. Industriellement, cette plante est pressée, puis séchée sur tambour rotatif. L’étape de pressage conduit à l’obtention de grandes quantités de jus, lui aussi riche en protéines. L’objectif de cette thèse a été de développer un procédé de bioraffinerie de la luzerne, applicable aux autres plantes fourragères, permettant la valorisation des toutes les fractions de la plante. La première étape consiste en un fractionnement thermo-mécanique de la luzerne entière par extrusion bi-vis. Deux fractions sont obtenues : un résidu fibreux solide en partie déshydraté, pouvant être utilisé dans la filière agro-matériaux, et un filtrat vert, riche en protéines. L’extrusion bi-vis est une alternative intéressante aux procédés classiques de déshydratation, car l’étude de l’optimisation des paramètres d’extrusion a permis de montrer qu’il est possible de récupérer la grande majorité des protéines de la plante dans le filtrat. Ce filtrat subit par la suite une séparation liquide/solide par centrifugation, permettant la récupération d’un culot vert, dont on peut extraire la chlorophylle. Le jus clarifié est ultrafiltré, puis traité par chromatographie hydrophobe, avec l’huile de tournesol comme solvant extracteur, de manière à séparer différentes protéines. L’étude plus fondamentale de la fixation des protéines sur résine a permis de modéliser le fractionnement des protéines par interactions hydrophobes. / Alfalfa is a common Legume, cultivated as a forage crop, thanks to its high protein content. In the green crop industry, alfalfa is pressed and dried on a rotative cylinder. The pressing step leads to the production of large amounts of green juice, rich in proteins. The aim of this work was to develop a biorefinery process for alfalfa, which could be adapted to other green crops, allowing the valorization of each fraction. The first step is the whole plant thermo-mechanical fractionation in the twin-screw extruder. Two fractions are obtained: a solid fibrous residue, partly dehydrated which could be valorized as an agro-material, and a green filtrate, rich in proteins. Twin-screw extrusion is an interesting alternative to usual industrial dehydration processes. Indeed, the study of the extruder parameters optimization showed that most of the alfalfa proteins can be recovered in the filtrate. This green extract is then centrifuged, in order to separate the solid particles. Chlorophyll can be extracted from the centrifugation pellet. The clarified juice is treated by ultrafiltration, and lastly fractionated thanks to hydrophobic chromatography, with sunflower oil as the solvent, in order to separate the proteins. The more fundamental study of proteins fixation on resins allowed us to modelize proteins fractionation using hydrophobic interactions.
67

The Making and Analysis of For Justin

Schwartz, Adam 19 December 2008 (has links)
This paper thoroughly examines the production of the thesis film, For Justin. Each area of the film's production is discussed and analyzed, including the writing, directing, production design, cinematography, editing, sound, and workflow. My decisions in these areas will be discussed at length and ultimately the final film will be analyzed in order to determine whether I achieved my goal of challenging myself to create a heartfelt, touching film with high production values for my twin brother, Justin.
68

Investigation into the twin-arginine translocation pathway of halophilic and thermophilic archaea

Kwan, Daniel January 2009 (has links)
The Twin arginine translocation pathway translocates fully folded proteins across cellular membranes and is only utilised by proteins that fold before translocation. It is a unique process that is found in many bacteria, archaea and also in plant chloroplasts. Investigation of the bacterial and thylakoidal systems has revealed much of the substrates and the components involved in their translocation. Unfortunately, there are still many unanswered questions such as how substrates are directed to the membrane and the actual mechanism of translocation. This thesis specifically investigates the Tat pathway of halophilic and thermophilic archaea. To date, there has been a lack of research into the archaeal Tat pathway and it is possible that there are unique adaptations because of the extreme environments that these organisms inhabit. Chapter 3 specifically investigates the thermophiles Sulfolobus solfataricus and Sulfolobus tokodaii and attempts to purify their Tat complexes. By doing so it was hoped to learn more about the Tat components and their interactions. Further experiments were also performed to determine if the two S. solfataricus Tat operons provide specificity to the Tat substrates that translocate. Four separate areas of the Tat pathway of halophilic archaea (haloarchaea) were investigated in Chapters 4-7. Firstly, site-directed mutagenesis was used to analyse the signal peptides of haloarchaeal Tat substrates in more detail. Consequently, the resulting data led to the use of bioinformatics to analyse the Haloarchaeal signal peptide. The bioenergetics of the Tat system was then determined by analysing the effect of a variety of ionophores on translocation of the Tat substrates AmyH and SptA. Finally, a series of folding and stability assays were used to increase our understanding of AmyH, which could provide further information on why this protein, like many other haloarchaeal proteins, requires the Tat pathway for translocation.
69

Bridge damage detection and BIM mapping

Huethwohl, Philipp Karl January 2019 (has links)
Bridges are a vitally important part of modern infrastructure. Their condition needs to be monitored on a continuous basis in order to ensure their safety and functionality. Teams of engineers visually inspect more than half a million bridges per year in the US and the EU. There is clear evidence to suggest that they are not able to meet all bridge inspection guideline requirements. In addition, the format and storage of inspection reports varies considerably across authorities because of the lack of standardisation. The availability of a comprehensive and open digital representation of the data involved in and required for bridge inspection is an indispensable necessity for exploiting the full potential of modern digital technologies like big data exploration, artificial intelligence and database technologies. A thorough understanding of bridge inspection information requirements for reinforced concrete bridges is needed as basis for overcoming the stated problem. This work starts with a bridge inspection guideline analysis, from which an information model and a candidate binding to Industry Foundation Classes (IFC) is developed. The resulting bridge model can fully store inspection information in a standardised way which makes it easily shareable and comparable between users and standards. Then, two inspection stages for locating and classifying visual concrete defects are devised, implemented and benchmarked to support the bridge inspection process: In a first stage, healthy concrete surfaces are located and disregarded for further inspection. In a second hierarchical classification stage, each of the remaining potentially unhealthy surface areas is classified into a specific defect type in accordance with bridge inspection guidelines. The first stage achieves a search space reduction for a subsequent defect type classification of over 90% with a risk of missing a defect patch of less than 10%. The second stage identifies the correct defect type to a potentially unhealthy surface area with a probability of 85%. A prototypical implementation serves as a proof of concept. This work closes the gap between requirements arising from established inspection guidelines, the demand for holistic data models which has recently become known as "digital twin", and methods for automatically identifying and measuring specific defect classes on small scale images. It is of great significance for bridge inspectors, bridge owners and authorities as they now have more suitable data models at hand to store, view and manage maintenance information on bridges including defect location and defect types which are being retrieved automatically. With these developments, a foundation is available for a complete revision of bridge inspection processes on a modern, digital basis.
70

Genetic and Environmental Influences on Executive Functioning in Middle Childhood: The Role of Early Adversity

January 2018 (has links)
abstract: This study examined whether early adversity at 30-months moderated the heritability of common and individual components of EF at 8 years. It was hypothesized that early adversity would not moderate the common EF factor, but instead moderate individual EF components. The sample included 208 twin pairs from the Arizona Twin Project. Early Adversity, assessed at 30 months of age, included Parenting Daily Hassles, low perceived MOS social support, punitive punishment (Parental Responses to Child Misbehavior), home chaos (Confusion, Hubbub, and Order Scale), CES-D maternal depression, and low maternal emotional availability. EF at 8 years included the Eriksen Flanker Task, Continuous Performance Task, Digit Span Forward and Backward, and parent-reported Attentional Focusing and Inhibitory Control (Temperament in Middle Childhood Questionnaire). For both early adversity and EF, the first principal components were extracted as composites. A confirmatory factor analysis was also conducted to index common EF. Genetic analyses were tested on the common EF composites as well as each individual task using umx. Univariate models revealed genetic influences on all individual measures and common EF, with broad sense heritability from .22 (Digit Span Backwards) to .61 (parent-reported inhibitory control). Shared environmental influences were found for the Flanker Task (.13) and parent-reported inhibitory control (.24), and E was moderate to high (.40-.73) for all measures except parent-report inhibitory control (.15) and attentional focusing (.31). Moderation of heritability was not observed in for Digit Span Forward, Digit Span Backward, and Attentional Focusing. However, the nonshared environment was moderated for Common EF, and the Flanker Task, and additive genes and the nonshared environment were moderated for the Continuous Performance Task and Inhibitory Control. Generally, total variance decreased as early adversity increased, suggesting that homes with low levels of adversity may allow children to interact with more proximal processes that can promote EF development. / Dissertation/Thesis / Masters Thesis Psychology 2018

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