Background: Alginate overproduction in P. aeruginosa, also referred to as mucoidy, is a poor prognostic marker for patients with cystic fibrosis (CF). We previously reported the construction of a unique mucoid strain which overexpresses a small envelope protein MucE leading to activation of the protease AlgW. AlgW then degrades the anti-sigma factor MucA thus releasing the alternative sigma factor AlgU/T(σ22)to initiate transcription of the alginate biosynthetic operon. Results: In the current study, we mapped the mucE transcriptional start site, and determined that P mucEactivity was dependent on AlgU. Additionally, the presence of triclosan and sodium dodecyl sulfate was shown to cause an increase in P mucEactivity. It was observed that mucE-mediated mucoidy in CF isolates was dependent on both the size of MucA and the genotype of algU. We also performed shotgun proteomic analysis with cell lysates from the strains PAO1, VE2 (PAO1 with constitutive expression of mucE) and VE2ΔalgU (VE2 with in-frame deletion of algU). As a result, we identified nine algU-dependent and two algU-independent proteins that were affected by overexpression of MucE. Conclusions: Our data indicates there is a positive feedback regulation between MucE and AlgU. Furthermore, it seems likely that MucE may be part of the signal transduction system that senses certain types of cell wall stress to P. aeruginosa.

Background: Alginate overproduction in P. aeruginosa, also referred to as mucoidy, is a poor prognostic marker for patients with cystic fibrosis (CF). We previously reported the construction of a unique mucoid strain which overexpresses a small envelope protein MucE leading to activation of the protease AlgW. AlgW then degrades the anti-sigma factor MucA thus releasing the alternative sigma factor AlgU/T(σ22)to initiate transcription of the alginate biosynthetic operon. Results: In the current study, we mapped the mucE transcriptional start site, and determined that P mucEactivity was dependent on AlgU. Additionally, the presence of triclosan and sodium dodecyl sulfate was shown to cause an increase in P mucEactivity. It was observed that mucE-mediated mucoidy in CF isolates was dependent on both the size of MucA and the genotype of algU. We also performed shotgun proteomic analysis with cell lysates from the strains PAO1, VE2 (PAO1 with constitutive expression of mucE) and VE2ΔalgU (VE2 with in-frame deletion of algU). As a result, we identified nine algU-dependent and two algU-independent proteins that were affected by overexpression of MucE. Conclusions: Our data indicates there is a positive feedback regulation between MucE and AlgU. Furthermore, it seems likely that MucE may be part of the signal transduction system that senses certain types of cell wall stress to P. aeruginosa.

La presente tesis, trata sobre el uso de la metodología Six Sigma para la optimización de un área de mantenimiento de planta. Al estar usando como referencia una metodología los capítulos que aquí se presentan siguen el esquema DMAMC, donde se Define el problema, se Mide el proceso, se Analiza la causa raíz, se Mejora el proceso y por ultimo se Controla el mismo por medio de indicadores de gestión. En la etapa de Medir se implementan diferentes ganancias rápidas al proceso; esto no implica que la metodología haya cumplido su objetivo, six sigma busca mejorar aquellas causas raíz que no están a la simple vista de las personas que trabajan en el área o gerencia. Por ultimo la presente tesis propone mejoras así como los controles que deben de llevarse en el área de mantenimiento de planta. Es aquí donde se ve el compromiso de la gerencia y la jefatura del área con el proyecto ya que de ellos depende que las mejoras y el control caminen y den paso a la optimización del proceso. / Tesis

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El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / Even though there is a high demand for clothing articles in the market, they do not meet quality standards. This can be appreciated after the clothes are washed and dried and the study revealed that over 20% of the items were returned each month. This occurs when the acquisition of raw materials is focused exclusively on the price. Thus, there are no requirements for compliance with any technical specifications that would enable the production process to be equipped with quality raw materials. Additionally, the absence of control over the quantity of consumables based on demand generates reprocessed inventory, thus damaging the fabric. Therefore, the proposed model was made through the Lean Six Sigma method to reduce waste and meet client requirements. The results were a decrease in returns by over 16.5% and an increase in productivity by 28.5%.

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Due to the rapid growth of the communication market, a large amount of research is in process toward a high speed and high resolution sigma-delta A/D converter. This dissertation focuses on the design of a single-stage sigma-delta A/D converter with very low oversampling ratio for the wireless application. An architecture for a multibit single-stage delta-sigma A/D converter with two-step quantization is proposed. Both the MSB and LSB signals produced by the two-step quantization are fed back simultaneously to all integrator stages, making it suitable for low oversampling ratios. The two-step ADC avoids the problem that the complexity of an internal flash ADC increases exponentially with each added bit. A segmented architecture with coarse/fine DEM and DAC is proposed to reduce the complexity of DEM and DAC due to the large internal quantizer. The consequence of the segmentation, mismatch between coarse and fine DACs can be noise-shaped by using a digital requantization (REQ) algorithm. A second-order single-stage sigma-delta A/D converter with 8-bit two-step inner quantization is proposed in this dissertation, which employs the feed-forward branches to reduce the integrator output swing. The proposed modulator is implemented with TSMC 0.25 μm mixed-signal process, using the switched-capacitor circuit. The measured system achieves the dynamic range of 70 dB under an oversampling ratio of 16 with the REQ algorithm reducing the noise floor in the signal bandwidth by 20 dB.

The computer service industry has been expanding dramatically due to the increase in the number of computing machineries in the last two decades. The entrance of large size companies in the market and the release of online tools that have the ability for diagnosing and troubleshooting hardware and software issues have boosted the competition. In the meantime, many of the small and medium size companies find themselves unable to keep their customers satisfied since their competitors provide high quality service with lower cost. The lack of a good measurement system to assess and analyze the satisfaction level with the provided service is the fundamental cause of customer decline. The aim of this study is to construct a robust framework to measure customer satisfaction and highlight the root causes of dissatisfaction in the computer service sector. This framework brings together the key aspects of Six Sigma and SERVQUAL instruments into a structured approach to measure and analyze customer satisfaction with computer services. It deploys the DMAIC problem solving methodology along with the SERVQUAL model, which contributes service dimensions and the Gap Analyze technique. Literature review indicates there have not been enough studies conducted to integrate Lean Six Sigma with SERVQUAL. To explore the effectiveness of the current framework, a computer service company has been selected. The satisfaction levels are calculated and the root causes of dissatisfaction have been identified. With a low overall customer satisfaction level, the company did not fulfill their customer requirements due to five major causes. Eliminating those causes will boost customer satisfaction, reduce the cost of acquiring new customers and improve the company performance in general.

Six Sigma is a business improvement strategy that aims to improve process performance using a structured methodology that identifies and removes the causes of defects in manufacturing and business processes, while implementing the lean concepts attempts to remove wasteful activities from those processes. In practice, the Six Sigma strategy and the Lean philosophy are combined and often viewed as one integrated philosophy, where the philosophy of Lean Six Sigma simultaneously removes wasteful activities from a process and reduces the variability of that process. This thesis research reviews the concepts and implementation of Lean thinking, Six Sigma strategy, and the integrated concept of Lean Six Sigma, with emphasis in service organizations. Most importantly, this thesis summarizes the critical success factors for implementing Lean Six Sigma within a service business environment and categorizes them within a proposed multi-level taxonomy that can be used by service business units and service providers to improve the .success of Lean Six Sigma implementation

Produced Water (PW) is the largest volume of waste that is normally generated during oil and gas production. It has large amounts of contaminants that can cause negative environmental and economic impacts. The management method for PW relies highly on types and concentrations of these contaminants, which are field dependent and can vary from one oil field to another. Produced water can be converted to fresh water if these contaminants are removed or reduced to the acceptable drinking water quality level. In addition, increasing oil production rate and reducing amounts of discharged harmful contaminants can be achieved by removing dissolved hydrocarbons from PW. In order to identify the types of these contaminants, effective tools and methods should be used. Six Sigma, which uses the DMAIC (Define- MeasureAnalyze- Improve- Control) problem-solving approach is one of the most effective tools to identify the root causes of having high percentages of contaminants in produced water. The methodology also helped develop a new policy change for implementing a way by which this treated water may be used. Six Sigma has not been widely implemented in oil and gas industries. This research adopted the Six Sigma methodology through a case study, related to the southern Iraqi oil fields, to investigate different ways by which produced water can be treated. Research results showed that the enormous amount of contaminated PW could be treated by using membrane filtration technology. In addition, a Multi Criteria Decision Making (MCDM) framework is developed and that could be used as an effective tool for decision makers. The developed framework could be used within manufacturing industries, services, educational systems, governmental organizations, and others. iv This work is dedicated to my scholarship providers and supporters wit