Oxidative stress-inducing chemical contamination in the environment is a significant concern for public health. The depletion of antioxidants by these chemicals results in oxidative stress which may cause detrimental effects in many cell types. For example, multiple stress responses may be activated in bacteria and several disorders including neurodegenerative disorders may occur in mammalian organisms. Oxidative chemicals also have negative effects on engineered water systems as an oxidative stress response in bacteria has been implicated to cause process failure in wastewater treatment facilities. Therefore, it is essential to monitor oxidative chemical contamination in water environments to provide early warning of potential negative effects. Whole-cell biosensors that indicate bacterial stress responses to oxidative toxic agents can be powerful tools in environmental monitoring. An oxidative stress response found in many Gram-negative heterotrophic bacteria called the glutathione-gated potassium efflux (GGKE) mechanism is a good biological indicator to be used in a biosensor designed to detect the presence of oxidative chemicals in water. The authors of this study propose the development of a GGKE biosensor using an environmental strain of Pseudomonas aeruginosa. The abundance of the global antioxidant glutathione, the gating compound in GGKE, in various cell types suggests that there may be connections between the responses of the different cell types to oxidative stress. In this study, specific oxidative stress responses in two distantly related cell types were studied: the GGKE mechanism in Gram-negative heterotrophic bacteria, and mitochondrial dysfunction in rat brain cells. Furthermore, the use of an octanol-based emulsification method for the immobilization of P. aeruginosa in calcium alginate microbeads was evaluated for long-term mechanical stability, viability, and GGKE response of the immobilized cells. The immobilization of cells is an important factor in the design of a whole-cell biosensor, and must yield viable and active cells over time. This study showed that the dose-dependent responses of GGKE in Pseudomonas aeruginosa cells and of mitochondrial dysfunction in a mixed culture of rat brain cells to a model oxidative electrophilic chemical, N-ethylmaleimide, correspond well to each other. We also showed that both responses are accompanied by the depletion of intracellular glutathione, which precedes the GGKE response in P. aeruginosa as well as mitochondrial damage in rat brain cells. Thus, this study suggests that bacterial responses to oxidative stress involving glutathione, such as GGKE, could potentially be used as an early warning to predict the presence of bioavailable oxidative chemicals that can induce oxidative stress in eukaryotic systems. Although further research is needed, this suggests that bacterial stress response biosensors may be used to predict oxidative stress responses in mammalian brain cells. The octanol-based emulsification method produced P. aeruginosa encapsulated alginate microbeads with an average diameter of 200 μm. The microbeads were mechanically stable in solutions containing up to 20 mg/L K+ for 15 days. LIVE/DEAD® and specific oxygen uptake rate (SOUR) analyses showed that the microbead-immobilized cells recovered their membrane integrity within 5 days but not their net respiration potential. The microbead immobilized cells had no net GGKE potential in response to 50 mg/L N-ethylmaleimide after 14 days whereas water-based alginate bead (2mm) immobilized cells did, albeit at a reduced level to planktonic cells. Confirmation experiments revealed that octanol impeded cellular activities of the immobilized cells. Overall, this study showed that the octanol-based emulsification method is not suitable for the immobilization of P. aeruginosa for use in the GGKE biosensor and other microscale immobilization methods should be evaluated. / Master of Science

The Emitter Controlled Thyristor (ECT) is a new MOS-Gated Thyristor (MGT) that combines the ease of a MOS gate control with the superior current carrying capability of a thyristor structure for high-power applications. An ECT is composed of an emitter switch in series with the thyristor, an emitter-short switch in parallel with the emitter junction of the thyristor, a turn-on FET and the main thyristor structure. Numerical analysis shows that the ECT also offers superior high voltage current saturation capability even for high breakdown voltage ratings. Two different ECT structures are investigated in this research from numerical simulations to experimental fabrications. A novel ECT structure that utilizes IGBT compatible fabrication process was proposed. The emitter short FET, emitter switch FET and turn-on FET are all integrated with a high voltage thyristor. Numerical simulation results show that the ECT has a better conductivity modulation than that of the IGBT and at the same time exhibits superior high voltage current saturation capability, superior FBSOA and RBSOA. The technology trade-off between turn-off energy loss and forward voltage drop of the ECT is also better than that of the IGBT because of the stronger conductivity modulation. A novel self-aligned process is developed to fabricate the device. Experimental characteristics of the fabricated ECT devices show that the ECT achieves lower forward voltage drop and superior high voltage current saturation capability. A Hybrid ECT (HECT) structure was also developed in this research work. The HECT uses an external FET to realize the emitter switching function, hence a complicated fabrication issue was separated into two simple one. The cost of the fabrication decreases and the yield increases due to the hybrid integration. Numerical simulations demonstrate the superior on-state voltage drop and high voltage current saturation capability. A novel seven-mask process was developed to fabricate the HECT. Experimental results show that the HECT could achieve the lower forward voltage drop and superior current saturation capability. The resistive switching test was carried out to demonstrate the switching characteristics of the HECT. / Master of Science

The Emitter Controlled Thyristor (ECT) is a new MOS-Gated Thyristor (MGT) that combines the ease of a MOS gate control with the superior current carrying capability of a thyristor structure for high-power applications. An ECT is composed of an emitter switch in series with the thyristor, an emitter-short switch in parallel with the emitter junction of the thyristor, a turn-on FET and the main thyristor structure. Numerical analysis shows that the ECT also offers superior high voltage current saturation capability even for high breakdown voltage ratings. Two different ECT structures are investigated in this research from numerical simulations to experimental fabrications. A novel ECT structure that utilizes IGBT compatible fabrication process was proposed. The emitter short FET, emitter switch FET and turn-on FET are all integrated with a high voltage thyristor. Numerical simulation results show that the ECT has a better conductivity modulation than that of the IGBT and at the same time exhibits superior high voltage current saturation capability, superior FBSOA and RBSOA. The technology trade-off between turn-off energy loss and forward voltage drop of the ECT is also better than that of the IGBT because of the stronger conductivity modulation. A novel self-aligned process is developed to fabricate the device. Experimental characteristics of the fabricated ECT devices show that the ECT achieves lower forward voltage drop and superior high voltage current saturation capability. A Hybrid ECT (HECT) structure was also developed in this research work. The HECT uses an external FET to realize the emitter switching function, hence a complicated fabrication issue was separated into two simple one. The cost of the fabrication decreases and the yield increases due to the hybrid integration. Numerical simulations demonstrate the superior on-state voltage drop and high voltage current saturation capability. A novel seven-mask process was developed to fabricate the HECT. Experimental results show that the HECT could achieve the lower forward voltage drop and superior current saturation capability. The resistive switching test was carried out to demonstrate the switching characteristics of the HECT. / Master of Science

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Made available in DSpace on 2016-04-26T20:20:34Z (GMT). No. of bitstreams: 1 Gabriel Ismael Folgado Blanco.pdf: 530665 bytes, checksum: 618b2db33377311b37378a9fa0e7cc8b (MD5) Previous issue date: 2011-11-01 / The intention of this task is to face, under the focus of de Urban Law, the practice of the property market in promoting an undertaking residential model relatively recent, that is called by several names, been however, more well-known by closed division of land into lots or closed condominiums . For that it is necessary to transit through the fields of Constitutionalist Law, Administrative Law , Civil Law, as well as the support in others fields like Urbanization and Sociology, in order to understand at minimum the urban designer and the causes that make the success of the property undertaking market that, till now ,doesn t have its legal bases properly established. The challenge that goes through the whole task is the definition of the competences between the states of the federation in order do define precisely the each one s field in the area of Urban Law, especially in relation to the parcelling out of the soil. A permanent preoccupation was to make an approach that demonstrated the effects of these divisions of land into lots models, physically isolated, under the point of view of the urban planning, the territory organization and its consequences in relation to the human being fundamental rights and its correlation with the right of the city, approaching at the same time the effects concerning to the legal security. The task tried to put in evidence some aspects of this kind of urban intervention, under the point of view of the cities s social environmental upheld development, that hasn t got from the Judiciary the due attention, which has concentrated itself in the personal relationships aspects concerning to the payment of the condominium taxes or the undertakings residents s security. The task s audacious pretension is that the showed arguments contribute to an overture of a bigger reflection concerning to the regulation about this kind of urban solution that still doesn t have a definite legal structure / O presente trabalho tem por objetivo enfrentar, sob o enfoque do Direito Urbanístico, a prática do mercado imobiliário de promoção de um modelo, relativamente recente, de empreendimento habitacional, que atende por diversos nomes, sendo, entretanto, mais conhecido por loteamentos fechados ou condomínios fechados . Para tanto, inevitável o trânsito pelos campos do Direito Constitucional, do Direito Administrativo, do Direito Civil entre outros, bem como, o socorro no campo de outras matérias como do Urbanismo e da Sociologia, de modo a minimamente entender o desenho urbano e os motivos que ensejam o sucesso mercadológico de empreendimentos imobiliários que até hoje não tem suas bases jurídicas devidamente constituídas. Desafio que transcorre todo o trabalho se apresenta na definição de competências entre os entes federativos, de modo a definir com precisão o campo de cada um na área do Direito Urbanístico, especialmente em relação ao parcelamento do solo. Uma preocupação permanente foi a de realizar uma abordagem demonstrativa dos efeitos desses modelos de loteamentos que se isolam fisicamente, sob o ponto de vista do planejamento urbano, do ordenamento territorial e suas conseqüências em face dos direitos fundamentais da pessoa humana, sua co-relação com o direito à cidade, abordando ao largo os efeitos quanto à segurança jurídica. O trabalho procurou evidenciar alguns aspectos desse tipo de intervenção urbanística, sob o ponto do desenvolvimento sócio-ambiental sustentável das cidades, olhar esse que não tem obtido por parte do Poder Judiciário a devida atenção, o qual tem se concentrado nos aspectos das relações pessoais, no que tange ao pagamento das taxas condominiais ou sob o vetor da segurança de quem reside nesses empreendimentos. A pretensão audaciosa é a de que os argumentos apresentados contribuam para a abertura de uma maior reflexão quanto à regulamentação desse tipo de solução urbanística que ainda não possui uma conformação jurídica definida

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 5 uppsatser.

Thesis (MA (Geography and Environmental Studies))--Stellenbosch University, 2009. / ENGLISH ABSTRACT: Gated developments (GDs) are a global phenomenon with their presence and numbers increasing in many cities throughout the world. This is also true for cities in South Africa, including Cape Town which has seen a dramatic increase in the number of GDs during the last decade. GDs pose significant challenges to their surrounding urban environments and to cities as a whole because of the spatial and social fragmentation associated with such developments. The challenges created by GDs are especially relevant in the context of the post-apartheid planning goals of integration and sustainability of cities in South Africa. There is a pressing need to understand these GDs in their social and spatial contexts. This study examined aerial photographs to establish the spatial distribution of GDs, ascertain their growth over time and determine clustering of the phenomenon in the north-eastern suburbs of Cape Town. The architectural characteristics and the security measures employed by the GDs were investigated through field observations of a sample of GDs. The socio-economic and demographic features, as well as the daily activity spaces of the residents of the GDs, were determined in a questionnaire survey of a sample of these inhabitants. These investigations provided a detailed look at the gating phenomenon as it manifests in a post-apartheid city, namely Cape Town. The study is of particular interest to urban geographers, town and regional planners, and urban policy makers dealing with the integration of post-apartheid cities. The study found that the GDs constrain progress toward reaching the post-apartheid planning goals of integration and urban sustainability by their contribution to increasing urban fragmentation and urban sprawl through their clustering close to the urban edge. The GDs also promote social segregation through their high perimeter defences with low visual permeability which effectively separate the developments from their neighbourhoods. The use of a larger sample on which to base the socioeconomic and demographic profiles of GD residents as well as the use of more recent aerial photography will enhance future studies of the gating phenomenon. A thorough analysis of travel patterns and traffic volumes in neighbourhoods with large clusters of GDs will advance an understanding of this phenomenon’s effects on urban segregation and fragmentation. / AFRIKAANSE OPSOMMING: Sekuriteitsoorde is ʼn globale verskynsel wat toenemend in teenwoordigheid en getalle wêreldwyd in die meeste stede voorkom. Dit is ook die geval in Suid-Afrikaanse stede, insluitend Kaapstad wat in die laaste dekade ʼn dramatiese toename in die getal sekuriteitsoorde beleef het. Sekuriteitsoorde hou ʼn paar gewigtige uitdagings vir die omliggende stedelike omgewings en dié vir die groter stad in as gevolg van die ruimtelike en sosiale fragmentasie wat met hierdie ontwikkelings geassosieer word. Hierdie uitdagings is veral relevant vir die huidige Suid-Afrikaanse beplanningsbeleid wat na 1994 in werking getree het en wat stedelike integrasie en volhoubare stedelike ontwikkeling beklemtoon. Dit is belangrik om sekuriteitsoorde binne hulle sosiale en ruimtelike kontekste te bestudeer. Lugfoto’s is bestudeer om die ruimtelike manifestasie (ligging, groei en konsentrasie) van hierdie verskynsel in Kaapstad se noordelike voorstede te ontleed. Verder is ʼn steekproef van sekuriteitsoorde ter plaatse ondersoek om die argitektoniese kenmerke en die sekuriteit maatreëls van die ontwikkelings te bestudeer. Die sosio-ekonomiese en demografiese profiele sowel as die daaglikse aktiwiteitsruimtes van sekuriteitsoordinwoners is deur middel van ʼn vraelysopname van ʼn steekproef van inwoners vasgestel. Hierdie ondersoeke het ʼn diepgaande blik op geslote ontwikkelings in stede wat gekenmerk is deur apartheidstyl beplanning (soos Kaapstad) gegee. Die bevindings is dus veral relevant vir stedelike geograwe, stads- en streeksbeplanners en stedelike beleidmakers wat met die integrasie van na-apartheidstede te doen het. Die studie het bevind dat hierdie ontwikkelings die bereiking van die na-apartheidsbeplanningsdoelwitte van stedelike integrasie en volhoubare stedelike ontwikkeling belemmer deur stedelike fragmentasie en stedelike wildgroei te bevorder deur konsentrasies van hierdie ontwikkelings naby die stedelike grens te vestig. Sosiale fragmentasie word ook deur hierdie ontwikkelings aangehelp deur hulle neiging om hoë grensmure met lae visuele deursigtigheid te gebruik wat effektief die ontwikkelings van hul buurt afsonder. Die studie kan verbeter word deur ʼn groter steekproef te gebruik om die sosioekonomiese en demografiese profiele op te baseer, asook om jonger lugfoto’s in te span. ʼn Deeglike ondersoek van reispatrone en verkeersvolumes in die woonbuurte met groot konsentrasies geslote ontwikkelings sal ʼn beter begrip van die verskynsel se impakte op stedelike segregasie en fragmentasie bevorder.

Studiens syfte är att finna och analysera mediediskurser ifråga om gated communities i Sverige under år 2015-2017. Tio tidningsartiklar har valts ut och analyserats med hjälp av kritisk diskursanalys (CDA), eller mer specifikt en modell i fem steg som Peter Berglez har tagit fram. Två extra steg har lagts till av mig i syfte att till fullo använda den teoroetiska utgångspunkten i form av gestaltningsteorin och den relationella identitetsmekanismen. Materialet består av tre artiklar från Värnamo Nyheter, två artiklar från Norra Halland, samt en artikel vardera från Smålandsposten, Vårt Kungsholmen, Mitt i Haninge, Trelleborgs Allehanda and TT. De första nio är lokaltidningar, medan TT är en oberoende rikstäckande nyhetsbyrå. Den kritiska diskursanalysen visar att gated communities avbildas på fyra huvudsakliga sätt: som en negativ och opassande association, som ett nödvändigt ont, som en oas och skön livsstil, samt som en risk för segregation. Diskurserna ifråga om gated communities ställdes sedan i relation till konstruktionen av en svensk identitet, vilket visade att allemansrätten, jämlikhet och öppenhet är grundläggande svenska värden som krockar med gated communities. Samtidigt utmanas dessa värden av andra samtida svenska värden såsom självförverkligande och strävan efter en hög levnadsstandard. Diskurserna jämfördes även med tidningarnas ideologi i syfte att hitta möjliga orsaker och konsekvenser / The aim of this study is to find and analyze discourses regarding gated communities in Sweden in the Swedish media 2015-2017. Ten articles has been selected and analyzed with the help of critical discourse analysis (CDA) and more specifically a model in five steps presented by Peter Berglez. Two extra steps have been added by me in order to make good use of the full theoretical approach: the framing theory and the theory of a relational mechanism of identity. The material consists of three articles from Värnamo Nyheter, two articles from Norra Halland, and one article each from Smålandsposten, Vårt Kungsholmen, Mitt i Haninge, Trelleborgs Allehanda and TT. The first nine articles are local newspapers and the last article is an independent nationwide news agency. The analysis shows that gated communities are depicted in four main ways: as a negative and unwanted association, a necessary evil, an oasis and good lifestyle, and last a risk of segregation. These discourses were then put in the context of the construction of a Swedish identity, which showed that the freedom to roam (allemansrätten), equality and openness are fundamental Swedish values that contradict gated communities. The comparison also shows that the values are currently being challenged by the Swedish value of self-expression and the strive for a good living standard. The discourses were also compared with the ideology of the newspapers and possible causes and consequences of the discourses were discussed.

The author investigates the performance of a time series based approach in predicting the risk of patients abandoning treatment in a treatment program for childhood obesity. The time series based approach is compared and contrasted to an approach based on static features (which has been applied in similar problems). Four machine learning models are constructed; one ‘Main model’ using both time series forecasting and three ‘reference models’ created by removing or exchanging parts of the main model to test the performance of using only time series forecasting or only static features in the prediction. The main model achieves an ROC-AUC of 0.77 on the data set. ANOVA testing is used to determine whether the four models perform differently. A difference cannot be verified at the significance level of 0.05, and thus, the author concludes that the project cannot show either an advantage or a disadvantage to employing a time series based approach over static features in this problem. / Författaren jämför modeller baserade på tidsserieförutsägelser med modeller baserade på statiska, fasta värden, till syfte att identifera patienter som riskerar att lämna ett behandlingsprogram för barnfetma. Fyra maskininlärningsmodeller konstrueras, en ‘Huvudmodell’ som använder sig av både tidsserieförutsägelser och statiska värden, och tre modeller som bryter ut delar av huvudmodellen för undersöka beteendet i modeller baserade enbart på statiska värden respektive enbart baserade på tidsserieförutsägelser. Huvudmodellen uppnår ROC-AUC0.77 på datasetet. ANOVA(variansanalys) används för att avgöra huruvida de fyra modellernas resultat skiljer sig, och en skillnad kan ej verieras vid P = 0:05. Följaktligen drar författaren slutsatsen att projektet inte har kunnat visa vare sig en signifikant fördel eller nackdel med att använda sig av tidsserieförutsägelser inom den aktuella problemdomänen.

Asparagine (N)-linked glycosylation occurs on 90% of membrane and secretory proteins and drives folding and trafficking along the secretory pathway. The N-glycan can be attached to an N-X-T/S-Y (X,Y ≠ P) consensus site by one of two oligosaccharyltransferase (OST) STT3 enzymatic isoforms either during protein translation (co-translational) or after protein translation has completed (post-translational). While co-translational N-glycosylation is both rapid and efficient, post-translational N-glycosylation occurs on a much slower time scale and, due to competition with protein degradation and forward trafficking, could be detrimental to the success of a peptide heavily reliant on post-translational N-glycosylation. In evidence, mutations in K+ channel subunits that shift N-glycosylation kinetics have been directly linked to cardiac arrhythmias. My thesis work focuses on identifying primary sequence factors that affect the rate of N-glycosylation. To identify the molecular determinants that dictate whether a consensus site acquires its initial N-glycan during or after protein synthesis, I used short (~ 100-170 aa) type I transmembrane peptides from the KCNE family (E1-E5) of K+ channel regulatory subunits. The lifetime of these small membrane proteins in the ER translocon is short, which places a significant time constraint on the co-translational N-glycosylation machinery and increases the resolution between co- and post-translational events. Using rapid metabolic pulse-chase experiments described in Chapter II, I identified several molecular determinants among native consensus sites in the KCNE family that favor co-translational N-glycosylation: threonine containing-consensus sites (NXT), multiple N-terminal consensus sites, and long C-termini. The kinetics could also be shifted towards post-translational N-glycosylation by converting to a serine containing-consensus site (NXS), reducing the number of consensus sites in the peptide, and shortening the C-termini. In Chapter III, I utilized an E2 scaffold peptide to examine the N-glycosylation kinetics of the middle X residue in an NXS consensus site. I found that large hydrophobic and negatively charged residues hinder co-translational N-glycosylation, while polar, small hydrophobic, and positively charged residues had the highest N-glycosylation efficiencies. Poorly N-glycosylated NXS consensus sites with large hydrophobic and negatively charged X residues had a significantly improved co-translational N-glycosylation efficiency upon conversion to NXT sites. Also in Chapter III, I adapted a siRNA knockdown strategy to definitively identify the OST STT3 isoforms that perform co- and post-translational N-glycosylation for type I transmembrane substrates. I found that the STT3A isoform predominantly performs co-translational N-glycosylation while the STT3B isoform predominantly performs post-translational N-glycosylation, in agreement with the roles of these enzymatic subunits on topologically different substrates. Taken together, these findings further the ability to predict the success of a consensus site by primary sequence alone and will be helpful for the identification and characterization of N-glycosylation deficiency diseases.