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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.
361

Phi Beta Delta: Implementation of a self-maintaining web site

Pillutla, Pallavi 01 January 2007 (has links)
The purpose of this project was to develop an easy-to-maintain web site for the Gamma Lambda Chapter of Phi Beta Delta International Honor Society here at California State University, San Bernardino, which will manage complete and up-to-date information about the mission, members, officers and all the activities of the honor society.
362

Gesellschaftliche Verantwortung der Wirtschaft im Internet : quantifizierende Inhaltsanalyse von Websites unter dem Aspekt der gesellschaftlichen Verantwortung bei Unternehmen aus der Wirtschaftsregion Nürnberg und Deutschland /

Keck, Stefan. January 2007 (has links)
Zugl.: Erlangen, Nürnberg, Universiẗat, Diss., 2007.
363

Investigation of the interactions between the bacterial homologue to actin, and the chaperone GroEL/ES through a combination of protein engineering and spectroscopy / Undersökning av interaktionerna mellan MreB, den bakteriella homologen till aktin, och chaperonet GroEL/ES genom en kombination av protein engineering och spektroskopi

Blom, Lillemor January 2008 (has links)
<p>Molecular chaperones help many proteins in the cell reach their native conformation. The mechanism with which they do this has been studied extensively, but has not been entirely elucidated. This work is a continuation of the study done by Laila Villebeck et al. (2007) on the conformational rearrangements in the eukaryotic protein actin in interaction with the eukaryotic chaperone TRiC. In this study the intentions were to analyze the protein MreB, a prokaryotic homologue to actin, when interacting with the prokaryotic chaperone GroEL. The purpose was to investigate if the mechanisms of GroEL and TRiC are similar. The analysis of the conformation of MreB was to be made through calculations of fluorescence resonance energy transfer (FRET) between two positions in MreB labeled with fluorescein. A MreB mutant was made through site-specific mutagenesis to enable labeling at a specific position. Another single mutant and a corresponding double mutant needed for these measurements were avaliable from earlier studies. The results from fluorescence measurements on these mutants indicated that the degree of labeling was insufficient for accurate determination of FRET. Suggestions are made on improvements of the experimental approach for future studies.</p>
364

Nest-site Selection and Hatching Success of Three Tern Species Breeding in Baisha Islet, Penghu Island, Taiwan

Lin, Yu-kai 03 September 2007 (has links)
Three tern species, Roseate Tern (Sterna dougalli), Bridled Tern (Sterna anaethetus) and Crested Tern (Sterna bergii) co-bred at Baisha islet, east-north of Penghu, in the summer of 2006. Each species favored different kind of environment for nesting. All Crested Terns nested in the flat plane with vegetation; Roseate Terns in the cliff near the vegetation, and Bridled Tern primarily nested near the vertical rock or under a rocky roof. The Crested Tern had the highest nesting density, and Bridled Tern nested loosely. The hatching success of Roseate (75%) and Crested Tern (73%) were significantly higher than that of Bridled Tern (30%). Roseate and Crested Tern laid eggs synchronously and had apparently two wave of egg laying and the breeding performances between early- and late-laying period were quite different. The relationship between hatching success and nest-site characteristics of the three species was investigated. The results revealed that hatching success of Roseate Tern increased with the number of walls and neighbors. Early-laying nests (79%) and central nests (72%) were more successful than late (11%) and edge nests (45%) of Roseate Terns. The laying-period was also important factors affecting hatching success of Crested Tern. Overall, the low hatching success of the late-laying nests may be due to the change of environmental conditions and the losing advantage of group breeding in the late season. The low hatching success of Bridled Tern was considered owing to the asynchronous laying pattern, loosely built nesting and weak parental behaviors.
365

Structural Driving Factors for the Coupled Electron and Proton Transfer Reactions in Mitochondrial Cytochrome BC1 Complex: Binding Geometries of Substrates and Protonation States of Ionizable Amino Acid Side Chains Near Qi and Qo Sites

Nguyen, Bao Linh Tran 16 April 2014 (has links)
Coupled electron and proton transfer (CEPT) events are fundamental for many bioenergetic conversions that involve redox reactions. Understanding the details underlying CEPT processes will advance our knowledge of (1) how nature regulates energy conversion; (2) our strategies for achieving renewable energy sources; (3) how to cope with CEPT dysfunction diseases. Studies of the detailed mechanism(s) of CEPT in biological systems is challenging due to their complex nature. Consequently, controversies between the concerted and sequential mechanism of CEPT for many systems remain. This dissertation focuses on the bovine mitochondrial cytochrome bc1 complex. CEPT in the bc1 complex operates by a modified "Q-cycle"(1) and catalyzes electron transfer from ubiquinol (QH2), to cyt c via an iron sulfur cluster (ISC) and to the low potential hemes of cyt b, where it reduces ubiquinone (UQ). The electron transfer is coupled to the translocation of protons across the mitochondrial inner membrane, generating a proton gradient that drives ATP synthesis. Although the Q-cycle is widely accepted as the model that best describes how electrons and protons flow in bc1, detailed binding geometries at the Qo site (QH2 oxidation site) and Qi site (UQ reduction site) remain controversial. The binding geometries play critical roles in the thermodynamic and/or kinetic control of the reaction and protonatable amino acid side chains can participate in the proton transfer. The central focuses of this dissertation are molecular dynamics simulations of cofactor binding geometries near the Qo and Qi sites, calculations of the pKa values of ionizable amino acid side chains implicated in cofactor binding, especially the ISC-coordinated histidines, and implications for the proposed mechanism(s) of CEPT. For the first time, pKa values of the ISC-coordinated histidines are differentiated. The computed pKa values of 7.8±0.5 for His141 and 9.1±0.6 for His161 agree well with experiment (7.63±0.15 and 9.16±0.28). Thus, His161 should be protonated at physiological pH and cannot be the first proton acceptor in the QH2 oxidation. Water mediated hydrogen bonds between substrate models and the protein and water accessibility to the Qo and Qi sites were maintained in simulations, implying that water molecules are likely the proton donors and acceptors. / Bayer School of Natural and Environmental Sciences; / Chemistry and Biochemistry / PhD; / Dissertation;
366

Development of a riverbank asset management system for the city of Winnipeg

James, Alena 07 April 2009 (has links)
The City of Winnipeg, located at the confluence of the Red and Assiniboine Rivers, has over 240 km of natural riverbank property. The increased frequency and magnitude of flooding along the Red and Assiniboine Rivers over the past decade appears to have influenced the number of slope failures along riverbank property, resulting in the loss of both public green space and privately owned land. The loss of private and public property adjacent to the river has led to the loss of valuable real estate and public parkland amenities. To ensure that riverbank property is preserved for future generations, the City of Winnipeg wants to increase the stability of certain reaches of publicly owned riverbank property along the Red and Assiniboine Rivers that are prone to slope movements. Extensive research has been conducted on slope stability problems in the Winnipeg area, but a transparent prioritization procedure for the remediation of riverbank stability problems has not existed. Therefore, a Riverbank Asset Management System (RAMS) was developed for publicly owned riverbank property to prioritize riverbank slope stability problems along the Red and Assiniboine Rivers. The RAMS provides the City of Winnipeg with a rational approach for determining risk levels for specific reaches of the Red and Assiniboine Rivers. The calculated risk levels allow the City to develop recommended response levels for slope stability remediation projects in a fiscally responsible manner with minimal personal and political influences. This system permits the City to facilitate timely and periodic reviews of priority sites as riverbank conditions and input parameters change. / May 2009
367

Illustration d'une pratique communicationnelle du subjectif : présentation et récit de soi dans les sites de partage de photographies

Asselin, Geneviève January 2008 (has links) (PDF)
Ce mémoire rend compte d'une recherche de type exploratoire sur les formes d'exposition de soi dans les sites de partage photo tels que Flickr.com et Fokti.com. Plus précisément, nous y explicitons les pratiques de présentation et mise en récit de soi dans ces sites que nous pouvons désigner comme sites générés par les usagers. Notre démarche s'avère relativement novatrice puisqu'elle témoigne de l'émergence d'un nouvel objet communicationnel et qu'elle est le fruit d'une transversalité des disciplines. Notre objet d'étude nous permet d'aborder les codifications rendues possibles par certains aspects techniques de ces sites et d'explorer les significations communicationnelles et culturelles des sites de partage de photos. Ce faisant, nous examinerons les identités narratives véhiculées par les interventions et manipulations des usagers sur les sites choisis par une grille d'analyse socio-historique tout en appliquant des procédés d'observation empruntés à l'ethnologie. Ceci dans le but d'une compréhension à visée globale des principaux traits d'une culture observable à travers sa manifestation virtuelle. Les études de cas présentées ici nous permettent à la fois de comprendre l'usage d'un nouveau média et de mieux saisir comment son utilisation fabrique une identité individuelle mais aussi un modèle d'interaction formant une société virtuelle. Elles permettent également de comparer cette pratique d'autodiffusion au journal intime, un genre littéraire dont l'évolution est particulièrement observable dans les différentes phases de la modernité. Ainsi, la réflexion s'attarde autour de l'identité et de la culture de l'individualité dans la phase actuelle de la modernité et présente les sites de partage de photos comme objets porteurs et éloquents d'une culture contemporaine. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : Internet, Flickr, Fotkj, Communauté et société virtuelle, Présentation de soi, Identité narrativé, Modernité.
368

Régénération et réhabilitation urbaine des centres historiques arabo-musulmans : le cas de Tripoli (Libye)

Duval, Damien 01 1900 (has links) (PDF)
Aujourd'hui, la tendance est à la réappropriation durable des centres historiques dans une optique culturelle, touristique et socio-économique. À travers l'exemple de la médina de Tripoli (Libye), ce mémoire propose une étude géographique de la médina, principalement axé sur sa réhabilitation et sa régénération économique. Depuis la fin de l'embargo en 1999 et son retour sur la scène internationale au cours de l'année 2007, la Libye s'est dotée d'un programme de développement économique sans précédent dont le fondement même repose sur une réorganisation structurale de son réseau urbain. En se dotant d'un nouveau plan régional troisième génération (2000-2025), Tripoli entendait revitaliser son centre au moyen d'une politique urbaine volontariste axée sur la recherche d'une nouvelle urbanité et ainsi (ré)affirmer son rayonnement à l'échelle régionale. Dans un contexte qui lui était jusqu'à aujourd'hui favorable, la réhabilitation de la médina de Tripoli constitue l'un des projets les plus emblématiques du moment, et ce, à court et moyen terme. Carte maitresse de la nouvelle armature urbaine du littoral tripolitain et de sa mise en valeur, ce projet d'envergure se veut être la pierre angulaire d'une mise en cohérence du tissu et des fonctions de la capitale libyenne. Aussi, nous aurons à cœur de démontrer que, dans le cadre de la planification urbaine de la capitale libyenne, la réhabilitation de la médina constitue un enjeu urbain durable tant au niveau de la perception que de l'utilisation de l'espace tripolitain. En ce sens, le quartier historique, jadis muséifié sans aucune logique d'intégration urbaine, est en passe de devenir la clé d'une cohérence à l'échelle de la métropole en se « reconnectant » aux autres centralités présentes au sein de Tripoli. Cette recherche entend ici comprendre les enjeux de ce processus et ses conséquences sur la centralité urbaine. En rupture avec les travaux post-indépendance des années 1960, ce fait nouveau a pour conséquence de mettre à l'épreuve la place du patrimoine dans la ville arabe de demain. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : Tripoli, réhabilitation, régénération, centre historique, médina, centralité, patrimoine, développement.
369

Utveckling av verktyg för jämförelse av kundanpassade och platsspecifika enskilda avloppssystem : Development of a comparative tool for custom-made and site-specific on-site sewage systems

Uggla, Annika January 2012 (has links)
REFERAT Övergödning är ett högst reellt hot mot många av Sveriges sjöar och vattendrag och inte minst mot Östersjön. Utsläpp av ej tillräckligt renat avloppsvatten och läckage av näringsämnen från jordbruksmarker är problem som länderna kring Östersjön måste lösa. Sverige arbetar både nationellt och internationellt med att förbättra Östersjöns ekologiska status. Riksdagen har satt upp flera miljökvalitetsmål som bland annat tydliggör att Sverige måste minska tillförseln av näringsämnen till sjöar och vattendrag. Orsaken är att dessa föroreningar är en bidragande orsak till övergödning. Det här har resulterat i en ökad ansträngning från kommunerna att åtgärda diffusa utsläpp som enskilda avlopp. Ett enskilt avlopp antas vara en avloppsanläggning med en lokal hantering av hushållsavloppsvatten och är inte kopplat till ett regionalt ledningsnät och reningsverk. Avloppsvatten från hushåll består av BDT-vatten, vatten från bad, disk och tvätt, samt vatten från toalett. Avloppsvatten innehåller näringsämnen såsom fosfor och kväve samt organiskt material och bakterier. Om utloppsvattnet når recipienter utan att tillräcklig rening finns risk för övergödning och smittspridning. För att skydda grund- och ytvatten föreslår Naturvårdsverket att krav ställs på reduktion av näringsämnen och organiskt material för att det enskilda avloppet ska bli godkänt av kommunen. Sverige har uppskattningsvis en miljon enskilda avlopp varav nästan hälften bedöms vara undermåliga och i behov av att göras om. Det kan vara svårt för fastighetsägare att överblicka de krav som ställs och de många olika alternativ som finns för att anlägga eller göra om en avloppsanläggning. Ett verktyg som hanterar produkter och typlösningar för enskilda avlopp har tagits fram. Verktyget benämns LEA vilket står för Lösningar för Enskilda Avlopp och har utvecklats i Microsoft Excel®. LEA genererar och presenterar lösningsförslag utifrån plats- och kundspecifika parametrar vilka matas in i verktyget. Jämförelse kan göras mellan de föreslagna lösningsalternativen med avseende på olika parametrar, som exempelvis reduktionsgrad, utsläpp av näringsämnen och organiskt material, möjlighet till lokalt kretslopp och kostnad. LEA förväntas användas av sakkunnig och syftar till att effektivisera utredningar av enskilda avloppsanläggningar. Att användaren kontinuerligt uppdaterar och kompletterar databasen är centralt för verktygets fortsatta funktion och tillförlitlighet. / ABSTRACT Eutrophication is a serious threat to many of Sweden's lakes and streams, and in particular to the Baltic Sea. Discharge of inadequately treated waste water and leaching of nutrients from agricultural lands are problems that the countries surrounding the Baltic Sea have to find a solution to. Sweden strives both nationally and internationally towards improving the ecological status of the Baltic Sea. The government has decided upon several Environmental Quality Objectives that sets out that Sweden must reduce the emissions of nutrients to the sea, lakes and streams. This is of great importance as these are contributing factors to eutrophication. This has initiated the Swedish municipalities to investigate diffuse discharges such as small scale on-site sewage systems. An on-site sewage system is assumed to locally treat domestic waste water and is not connected to a waste water treatment plant. Domestic waste water includes greywater, which is the effluent from kitchen and bathroom, and most often also water from toilet use. The waste water contains nutrients such as phosphorus and nitrogen as well as organic matter and bacteria. If the waste water reaches the receiving waters without adequate treatment this is associated with a risk of eutrophication and contamination. The Swedish EPA has recommended reduction levels to be reached for organic matter, nitrogen and phosphorus. The municipalities are recommended to require these levels to be met for the on-site sewage system to be approved. Sweden has approximately one million on-site sewage systems of which nearly 50% is considered substandard and in need of upgrading. It may be difficult for property owners to overview the requirements as well as the large number of products and options available to construct or modify an on-site sewage system. A program, LEA, which handles products for household sewage systems, has been developed in Microsoft Excel®. The tool generates suggestions of different sewage systems depending on customer and site-specific parameters. Comparisons are made between the proposed solutions with respect to various parameters which include reduction efficiency, effluent emissions, on-site recycling and cost. The user of LEA can update and supplement the database, which is central to the tool's continued function and reliability. LEA is expected to be used by experts and aims to enhance investigations in the choice of on-site sewage systems.
370

Development of Risk Management Strategies for a Petro-Chemical Contaminated Site

Huang, Wen-yen 01 June 2007 (has links)
The subsurface environmental contamination investigation, assessment and remediation of petro-chemical contaminated site have been the most challenging environmental issues of environmental protection. If subsurface environmental mediums like soil and groundwater are contaminated, the investigation and remediation will always be time-consuming and costly even though they could not be cleaned up completely. Groundwater contaminated by chlorinated volatile solvents is more difficult to remedy owing to its property of dense non-aqueous phase liquid (DNAPL). This study focuses on petro-chemicals contaminated site whose subsurface environment is contaminated by chlorinated ethene. The study will also find out the efficient, effective and economic ways to identify and concretely delineate the characterization of subsurface environment and contamination, conduct human health risk management and take risk-based corrective action, so as to formulate an appropriate risk management strategy and solution. Firstly, this study applies a Triad approach to accelerate and streamline the investigation process of contaminated site. Introduction of project systematic planning, dynamic work strategy and in situ, real time survey or direct-push sampling like membrane interface probe, together with off-site measures like physical measurement and chemical analytic testing in laboratory, could reduce the key uncertain characteristics of subsurface environmental contamination and establish the conceptual cite models for health risk assessment cost-effectively. It is estimated that this method could save 6 million NTD and shorten 3 years¡¦ time in site characteristics delineation and remediation. If we wish to make the site defensible via managing the uncertain decision, the integration of Triad approach which is developed by United States Environmental Protection Agency, and Environmental Site Assessment, Accelerated Site Characterization, Health Risk Assessment and Risk-based Corrective action which were developed by American Society for Testing and Materials (ASTM), are proved in this study that they could help streamline the site characterization and remediation. This study is based on the conceptual site models of Triad Approach, the Risk-based corrective action of ASTM, the Health Risk Assessment and Evaluation Methods for Soil and Groundwater Contaminated Site, and also the software developed by the Taiwan Environmental Protection Administration. Through the health risk assessment of chlorinated ethenes contaminated site, this research aims to evaluate the quantitative health risk like chemical of concern, environmental medium, and human exposure pathway etc. The result of evaluation showed that the carcinogenic risk of tier 2 is 1.080E-01 which exceeds the acceptable risk-based standard, 1E-06; tier 2¡¦s non-carcinogenic risk, 1.819E+03, also exceeds the acceptable hazard index which is 1. Groundwater poses the highest risk among environmental media, followed by inhalation of vapor from contaminated soil and/or groundwater. The risk of inhalation of top soil particulates is the lowest. The most dangerous carcinogenic exposure of groundwater is using groundwater for shower and washing whose risk is 8.064E-02; the second highest carcinogenic pathway is groundwater ingestion. Trichloroethylene is the key chemical of concern which poses 95.6% of carcinogenic risk among all chemicals of concern. Groundwater ingestion poses the highest non-carcinogenic risk (8.919E+02), and the main chemical of concern is cis-1, 2-dichloroethylene. The main chemical of concern of soil volatilization is cis-1, 2-dichloroethylene, followed by trichloroethylene. If the site in this study wishes to reduce the health risk of human beings, it is suggested to simultaneously implement integrated risk-based corrective actions including institutional control, engineering control and remediation. For institutional control, prohibition of pumping groundwater and pumping well installation is the most cost-effective choice. For engineering control, concrete capping on uncovered surface soil is feasible when dealing with soil contamination. When it comes to groundwater contamination, steel sheet pile containment or pumping well installation could help intercept the migration of groundwater. Regarding remediation, in-situ chemical reduction injection or permeable reactive barrier, incorporated together with monitored natural attenuation are more practicable alternatives, however, they are time-consuming and costly. The process and result of this study could be the basis for managers and/or decision makers of contaminated site to conduct risk-based management and decision making.

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