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Mesoamerica is a biodiversity hotspot harbouring a great diversity of ecosystems and species. Amphibians are one of the most diverse groups in the region, unfortunately many populations are declining, and a considerable number have gone extinct. Amphibian populations are a fundamental and irreplaceable part of the ecosystems present in Mesoamerica and their loss would be devastating for Central American biodiversity therefore, understanding the pressures these populations are under and conserving them more effectively is of the upmost importance. Molecular genetics is a useful tool to understand more about a population's diversity and its interactions with its environment. For the first part of this project I developed microsatellite markers for the black-eyed tree frog Agalychnis moreletii to study the genetic diversity and population structure of the species. Then I used mitochondrial markers to study the genetic and evolutionary history of the species. I found that several populations have low genetic diversity as well as high inbreeding levels. There is genetic differentiation and population structure across its distribution range. Four different Evolutionary Significant Units (ESUs) were identified for A. moreletii, and it is crucial to create different management plans for each one since there are different pressures threatening them. We also believe this data challenges the conservation status of the A. moreletii as it is currently defined by the IUCN and shows this species is far more endangered than currently thought. Changing this categorisation will increase the protection of the species and the ecosystem it inhabits. iv I characterised the skin-bacterial communities of A. moreletii in Guatemalan populations and how the presence of the pathogen Batrachochytrium dendrobatidis has an effect on the bacterial composition. Skin-microbiome in A. moreletii seems hostmediated. Infected frogs harbour lower diversity of bacteria that non-infected frogs, which leaves these individuals more vulnerable. For the final part of the PhD I studied the skin-bacterial composition of Bolitoglossa salamanders and Plectrohyla matudai and how it changes once the animals are taken from the wild into captivity. I documented that the bacterial diversity and composition declines when animals are in quarantine, which can be a stressful stage of a captive study since it usually involves a small container with paper towels. This shows that tank enrichment is important in maintaining a diverse skin-microbiome in captive amphibians and therefore tank diversity is crucial in maintaining the health of individuals. The data gathered for my PhD will contribute to the conservation of amphibians and their ecosystems in Mesoamerica.

This study aims to develop a comprehensive understanding of the relationship between waiters' occupational identity and its antecedents. The consequences of occupational identity on work engagement and employee turnover are explored. The development of occupational identity includes progressing, transforming, conserving, emphasising or evaluating existing identities; consequently, instead of considering the formation of identity as a simple procedure of accepting a work position, occupational identity is an interactive and problematic procedure. Occupational identity is not a rigid construct but is constantly shaped by engagement with the values of companies and occupational life. Traditionally, research has concentrated on the merely operational aspect of workers' jobs. In contrast, this research aims to concentrate on waiters' sense of self and their identity in the workplace. Additionally, limited studies have focused on the relationship between occupational identity, its antecedents and consequences. This study applies a mixed-methodology, with predominion of quantitative approach, which is reinforced by understandings from an exploratory process which includes in-depth interiews and focus groups discussions. The conceptual model was created from the existing literature and qualitative study. In the second phase, the same conceptual model was adopted to assess waiters' perceptions in the context of Michelin-starred restaurnats in London. A sample of 398 participants permitted multivariate analysis of data to be undertaken. Exploratory factor analysis (EFA) was performed, Cronbach-alpha and confirmatory factor analysis (CFA) were also performed to guarantee that the scales developed and adapted were strong in terms of reliability and validity. Structural equation modelling (SEM) allowed the hypotheses between constructs to be scrutinised. The model established a good fit to the data, good convergent, discriminant and nomological validity and reliability. Founded on the statistical outcomes and the qualitative study (in-depth interviews and focus groups and the related literature), this study has found that, apart from employer branding, other antecedent factors, such as passion and authenticity, influence favourably the occupational identity of waiters. Additionally, the relationship between occupational identity and the consequences were assessed; the outcomes of the hypotheses checking established that occupational identity has a better effect on work engagement and turnover. Furthermore, the relationship between occupational identity, work engagement and turnover was confirmed. However, an unforeseen result was that the relationship between extroversion, education, interference and stereotype toward occupation identity were not significant. Overall, this thesis concludes that presenting occupational identity is a complex phenomenon. This study is one of the pioneers in systematic research which has operationalised and conceptualised the meaning of occupational identity, its antecedents and its consequences. This evaluation is estimated to be valuable in progressing existing understanding by providing theoretic consideration to the literature. The level of measurement and conceptualisation of the theory generalisation and testing theory as a principal influence of this thesis was to present a comprehensive overview of the perspectives of waiters on their occupational identity. Additionally, it is expected that this research will provide a significant contribution to the managerial knowledge and consideration of the policy-makers and employers about the holistic correlation between a positive occupational identity, its antecedents and its principal consequences. A well-defined perception of the magnitudes of the principal meanings would assist employers to contemplate occupational identities which are more likely to develop a favourable occupational identity and consequently to reduce employee turnover. This thesis has developed knowledge and understanding of the formation of occupational identity and its antecedents and consequences, although the outcomes are not without some limitations in the approach of sampling, analysis, and measurement. Recommendations are provided to stimulate further research to expand the innovative investigations of this study on occupational identity, its antecedents and consequences.

The focus is on real-time optimal decision making with application in advanced control systems. These computationally intensive schemes, which involve the repeated solution of (convex) optimization problems within a sampling interval, require more efficient computational methods than currently available for extending their application to highly dynamical systems and setups with resource-constrained embedded computing platforms. A range of techniques are proposed to exploit synergies between digital hardware, numerical analysis and algorithm design. These techniques build on top of parameterisable hardware code generation tools that generate VHDL code describing custom computing architectures for interior-point methods and a range of first-order constrained optimization methods. Since memory limitations are often important in embedded implementations we develop a custom storage scheme for KKT matrices arising in interior-point methods for control, which reduces memory requirements significantly and prevents I/O bandwidth limitations from affecting the performance in our implementations. To take advantage of the trend towards parallel computing architectures and to exploit the special characteristics of our custom architectures we propose several high-level parallel optimal control schemes that can reduce computation time. A novel optimization formulation was devised for reducing the computational effort in solving certain problems independent of the computing platform used. In order to be able to solve optimization problems in fixed-point arithmetic, which is significantly more resource-efficient than floating-point, tailored linear algebra algorithms were developed for solving the linear systems that form the computational bottleneck in many optimization methods. These methods come with guarantees for reliable operation. We also provide finite-precision error analysis for fixed-point implementations of first-order methods that can be used to minimize the use of resources while meeting accuracy specifications. The suggested techniques are demonstrated on several practical examples, including a hardware-in-the-loop setup for optimization-based control of a large airliner.

This qualitative, collective case study covers the experience of strategic decision making in a pharmaceutical and medical device manufacturing environment in Puerto Rico during the current economic crisis. The medical device and pharmaceutical manufacturing industry in Puerto Rico was selected because of the tax expirations targeting this specific industry and the predominance on the island this industry represents in the manufacturing environment. Despite Puerto Rico’s dominance in medical device and pharmaceutical manufacturing over the past 60 years, the current financial and government crisis poses a significant threat to executive level commitment toward maintaining operations on the island. Research questions focused on plant manager’s experiences and perspectives regarding the strategic decision-making process. Participant interviews included executives indirectly overseeing regulated facilities in Puerto Rico, four plant managers for medical device facility on the island and representatives of their direct staff, a former global operations leader for the pharmaceutical industry, and an economic representative in Puerto Rico. The interviews in conjunction with direct observation and document reviews of the four facilities provided the qualitative data used to develop a guideline of specific strategic decision making factors for future plant managers on the island and the results of the impact the external environment on the island is having on plant managers. The study concludes with recommendations for future research and application. The intent of the recommendations is to support continued manufacturing growth on the island.

The high fiber content of corn dried distillers’ grains with solubles (DDGS) can limit its utilization in swine diets. Pretreatment with heat and enzymatic predigestion of whole stillage (WS; slurry material that is dried into DDGS) can alleviate negative effects of dietary fiber and can improve digestive and fermentation characteristics of the feedstuff. However, optimal time and temperature of the heat pretreatment of WS, and best enzymes for predigestion of WS have not been identified. Experiments were conducted to identify optimal conditions for heat pretreatment and multienzyme predigestion of WS for pigs. First experiment was conducted to identify optimal temperature and time for later use in largescale pretreatment of WS for in vivo studies. The treatments were untreated WS, and WS that was pretreated (at 70 psi) for 10, 20, or 30 minutes and at 100, 120, 140, or 160°C in a 3 × 4 factorial arrangement. Sub-samples were subjected to porcine in vitro digestion and fermentation. An increase in pretreatment temperature linearly and quadratically increased (P

Glenn Murcutt, John Pawson y Anne Lacaton & Jean Philippe Vassal escenifican 3 concepciones diversas de la arquitectura actual. Una parte importante de su trabajo se ha volcado hacia el ámbito doméstico, y concretamente hacia la vivienda unifamiliar. Las casas de campo de Murcutt, de metal y madera, son respetuosas con la naturaleza y simultáneamente vernáculas y contemporáneas gracias a la inclusión de principios energéticos pasivos presentes en la arquitectura popular. Las viviendas de Pawson militan en un minimalismo trascendente, preciso y despojado que resulta a la vez exclusivo, severo, casi monacal, y se hace extensivo al diseño integral del mobiliario y otros elementos. Lacaton & Vassal priorizan cuestiones más inmanentes, como la sostenibilidad y el pragmatismo, mediante una construcción ligera y seca que incorpora la naturaleza al interior, vislumbrando una cierta provisionalidad y aparente despreocupación formal que remiten al pabellón o el campamento. La fotografía es un medio tremendamente poderoso que permite escoger y precisar nuestra mirada para difundir la realidad, y en este caso la arquitectura, a través de un tamiz cuidadosamente depurado. Fotografía y arquitectura interactúan de manera simbiótica, generando construcciones visuales capaces de reforzar las intenciones de los autores de ambas. La comunicación indagará en la íntima relación y las interacciones existentes entre la arquitectura y la fotografía de algunas viviendas de Murcutt, Pawson y Lacaton & Vassal con el fin de descubrir algunas intenciones y estrategias de estos 3 estudios para, a través de las imágenes generadas o controladas por ellos mismos, validar, reforzar y difundir internacionalmente sus diversas posiciones militantes.

The main objective was to develop a procedure based on differential optical absorption spectroscopy (DOAS) to measure atmospheric total column of ozone, using the automated instrument developed at the University of North Texas (UNT) by Nebgen in 2006. This project also explored the ability of this instrument to provide measurements of atmospheric total column nitrogen dioxide. The instrument is located on top of UNT’s Environmental Education, Science and Technology Building. It employs a low cost spectrometer coupled with fiber optics, which are aimed at the sun to collect solar radiation. Measurements taken throughout the day with this instrument exhibited a large variability. The DOAS procedure derives total column ozone from the analysis of daily DOAS Langley plots. This plot relates the measured differential column to the airmass factor. The use of such plots is conditioned by the time the concentration of ozone remains constant. Observations of ozone are typically conducted throughout the day. Observations of total column ozone were conducted for 5 months. Values were derived from both DOAS and Nebgen’s procedure and compared to satellite data. Although differences observed from both procedures to satellite data were similar, the variability found in measurements was reduced from 70 Dobson units, with Nebgen’s procedure, to 4 Dobson units, with the DOAS procedure.A methodology to measure atmospheric nitrogen dioxide using DOAS was also investigated. Although a similar approach to ozone measurements could be applied, it was found that such measurements were limited by the amount of solar radiation collected by the instrument. Observations of nitrogen dioxide are typically conducted near sunrise or sunset, when solar radiation experiences most of the atmospheric absorption.

This study aims to address concerns associated with ethically and legally implied practice of face-to-face supervisor-client contact. A two group, repeat measures design was employed to examine if there are differences between groups on therapy outcome measures, and client's, counselor's, and supervisors perceptions of the impact of face-to-face client-supervisor contact on therapy variables. Repeated measures ANOVAs were used to test group differences and found that there are no significant differences between audiovisual supervision and face-to-face supervisor-client contact when measuring symptom reduction and global functioning. However, the client and the supervisor both perceived that face-to-face client contact by the supervisor would have a greater impact on the outcome of therapy and on the ethical practice of psychotherapy. Implications for ethical, legal and supervisory processes are discussed.

In this paper I examine how one construction management company uses contract design and incentive design to respond to aspects of task complexity and relationship complexity present in its construction projects. In terms of contract design, I find that the company is unable to increase its use of cost-plus pricing when faced with technically complex projects. Instead, the company uses increased pre-execution design modification and price markups when technically complex projects are contracted with fixed-pricing. Further, I find that design modification is only margin-improving when used in projects that are both technically complex and fixed-price and that price markups are only margin-improving when projects are fixed-price. In terms of incentive design, I find that the company provides more qualitative feedback to employees and quantitatively rates employees with less centrality bias (i.e. more dispersed ratings) when employees work on fixed-price projects. Further, when employees work on fixed-price projects, they are granted greater average financial rewards, their financial rewards are relatively more based on input-behaviors (i.e. less based on output-results), and their bonuses, raises and promotions appear to be awarded with more managerial discretion (i.e. are less systematic.), subjectivity; fixed-price; cost-plus; complexity; feedback; incentives