Thesis (Ph. D.)--Carleton University, 2000. / Also available in electronic format on the Internet.

The experiments studied the ability to perceive visual, events of a very simple kind: the appearance and disappearance of isolated dots in random dot patterns. The aim of the investigation was to explore the limits of this ability and clarify the relationship, between event perception and sensory storage. The first series of experiments studied the ability to detect the appearance and disappearance of single dots. Under appropriate conditions such changes can be detected in a pattern containing 1024 dots with 98% accuracy. This level of accuracy was largely maintained over manipulation of the number of dots in the pattern, pattern size and separation between dots. Performance was unaffected by whether pattern luminance was uniform or not. It is argued that to explain this performance the notion of sensory integration must be augmented by the concept of sensory differentiation. The ability to detect events was further investigated as a function of pattern complexity and ISI. The storage underlying event detection has a very high capacity and a short duration. The second series of experiments investigated the ability to perceive patterns of events. Letters defined by either appearances or disappearances were accurately identified; thus a pattern which was not visible was made visible by its disappearance. A measure of localization was obtained by requiring subjects to judge whether three events were aligned. It is concluded that both onset and offset of a pattern convey information about form but that acuity for events is poorer than for sustained stimuli. The possibility that event perception is achieved by integration at short stimulus durations was investigated by varying the durations of the patterns before and after the events. Little evidence for event perception by integration was found; increasing the durations of the patterns either improved performance or had little or no effect on it. The final experiment examined a conflict between the present results and studies of visual integration. The ability to perceive mixtures of appearances and disappearances was investigated and found to be poorer than the ability to process either type of event alone. The ability to detect and locate events is highly developed. This ability seems well adapted to the detection and perception of significant change in the natural environment. In contrast to the increasing scepticism concerning the function of sensory storage it is concluded that event perception is an important visual function in which sensory storage is clearly implicated.

O poliuretano (PU) representa um dos grupos mais importantes de polímeros, com uma grande variedade de tipos e alta versatilidade de aplicações. É uma classe de polímeros na qual as unidades formadoras da cadeia polimérica são interligadas por ligações uretânicas, -O(CO)(NH)- . As macromoléculas são formadas pela reação de pré-polímeros contendo grupos terminais hidroxila com di-isocianatos. Quando excesso de diisocianato é empregado, a macromolécula resultante terá, em suas extremidades, grupos isocianato que podem então reagir com diferentes dióis poliméricos para extender adicionalmente as cadeias, ou com trióis para formar ligações cruzadas (Allcock et al., 2003). Devido a alta versatilidade do poliuretano e por ser o principal componente de produtos de alto consumo como colchões e geladeiras, o volume de resíduo de PU gerado é cada vez maior e por se tratar de um termo-fixo sua reciclagem não é um processo simples. O objetivo do presente trabalho é analisar os efeitos do uso de um poliol reciclado através de um processo de glicólise especifico nas propriedades mecânicas de uma espuma rígida de poliuretano. Diversos métodos de glicólise foram analisados da literatura e com base nas informações encontradas uma rota ótima foi proposta/escolhida. O produto gerado foi então caracterizado e utilizado em diferentes proporções em substituição ao poliol base em formulações padrão de espumas rígidas de poliuretano, de forma que os efeitos da adição do mesmo sobre as características finais relevantes da espuma pudessem ser observadas. O processo de reciclagem apresentado no presente estudo mostrou-se um processo efetivo no tratamento de resíduos industriais de espuma de poliuretano rígido, uma vez que o processo é rápido, de custo relativamente baixo e produz um produto final de qualidade comparável ao dos produtos virgens existentes no mercado. A funcionalidade e número de OH superiores do poliol recuperado trazem inclusive melhorias na estrutura mecânica da espuma final obtida a partir do uso do mesmo. A presença de impurezas advindas de reações secundárias mostraram sua influência na alteração da reatividade da reação de formação da espuma de poliuretano, porém este fato pôde ser ajustado através de alterações no nível de catalisadores adicionados a formulação. / The polyurethane (PU) represents one of the most important groups of polymers, with very versatile types and applications. It is a class of polymers in which the polymeric chain components are linked by uretanic linkages, -O(CO)(NH)-. The macromolecules are formed by the reaction of pre-polymers containg hydroxyl end groups with di- isocyanates. When excess of Isocyanate is used, the resulting macromolecule will have, in its edges, isocyanate groups that can react with different polymeric diols to extent additionally the chains, or with triols to form cross-linked polymers. (Allcock et al., 2003) The unlimited nature of the components A and B plus the several applications makes the PU one of the most versatile plastics. Due to its high versatility and for being the main component in mass consumption products like refrigerators and mattresses, the volume of PU residues generated is each time higher and once it is a thermoset its recycling methods are not easy. The objective of the present work is analyzing the effects of the use of a recycled polyol obtained through a specific glycolysis process in the mechanical properties of rigid PU foam. Different glycolysis methods were analyzed from previous art and an ideal route was established. The recycled polyol was characterized and used in different proportions in substitution of the conventional polyol in standard formulations for rigid foam production, thus the effects of this substitution could be observed. The proposed recycling process showed to be very effective in the recovering of polyols from PU rigid foam residues, once the process is fast, relatively low cost and produces a final product with equivalent quality of a conventional polyol. The higher functionality and OH number of the recovered polyol brings to the final foam superior mechanical properties. The presence of secondary products like primary amines generated in the process could be noticed by the increase in the reactivity of the formulations using the recycled polyol, although this fact was proved to be manageable through adjustments in the aminic catalyst add to the formulations.

O poliuretano (PU) representa um dos grupos mais importantes de polímeros, com uma grande variedade de tipos e alta versatilidade de aplicações. É uma classe de polímeros na qual as unidades formadoras da cadeia polimérica são interligadas por ligações uretânicas, -O(CO)(NH)- . As macromoléculas são formadas pela reação de pré-polímeros contendo grupos terminais hidroxila com di-isocianatos. Quando excesso de diisocianato é empregado, a macromolécula resultante terá, em suas extremidades, grupos isocianato que podem então reagir com diferentes dióis poliméricos para extender adicionalmente as cadeias, ou com trióis para formar ligações cruzadas (Allcock et al., 2003). Devido a alta versatilidade do poliuretano e por ser o principal componente de produtos de alto consumo como colchões e geladeiras, o volume de resíduo de PU gerado é cada vez maior e por se tratar de um termo-fixo sua reciclagem não é um processo simples. O objetivo do presente trabalho é analisar os efeitos do uso de um poliol reciclado através de um processo de glicólise especifico nas propriedades mecânicas de uma espuma rígida de poliuretano. Diversos métodos de glicólise foram analisados da literatura e com base nas informações encontradas uma rota ótima foi proposta/escolhida. O produto gerado foi então caracterizado e utilizado em diferentes proporções em substituição ao poliol base em formulações padrão de espumas rígidas de poliuretano, de forma que os efeitos da adição do mesmo sobre as características finais relevantes da espuma pudessem ser observadas. O processo de reciclagem apresentado no presente estudo mostrou-se um processo efetivo no tratamento de resíduos industriais de espuma de poliuretano rígido, uma vez que o processo é rápido, de custo relativamente baixo e produz um produto final de qualidade comparável ao dos produtos virgens existentes no mercado. A funcionalidade e número de OH superiores do poliol recuperado trazem inclusive melhorias na estrutura mecânica da espuma final obtida a partir do uso do mesmo. A presença de impurezas advindas de reações secundárias mostraram sua influência na alteração da reatividade da reação de formação da espuma de poliuretano, porém este fato pôde ser ajustado através de alterações no nível de catalisadores adicionados a formulação. / The polyurethane (PU) represents one of the most important groups of polymers, with very versatile types and applications. It is a class of polymers in which the polymeric chain components are linked by uretanic linkages, -O(CO)(NH)-. The macromolecules are formed by the reaction of pre-polymers containg hydroxyl end groups with di- isocyanates. When excess of Isocyanate is used, the resulting macromolecule will have, in its edges, isocyanate groups that can react with different polymeric diols to extent additionally the chains, or with triols to form cross-linked polymers. (Allcock et al., 2003) The unlimited nature of the components A and B plus the several applications makes the PU one of the most versatile plastics. Due to its high versatility and for being the main component in mass consumption products like refrigerators and mattresses, the volume of PU residues generated is each time higher and once it is a thermoset its recycling methods are not easy. The objective of the present work is analyzing the effects of the use of a recycled polyol obtained through a specific glycolysis process in the mechanical properties of rigid PU foam. Different glycolysis methods were analyzed from previous art and an ideal route was established. The recycled polyol was characterized and used in different proportions in substitution of the conventional polyol in standard formulations for rigid foam production, thus the effects of this substitution could be observed. The proposed recycling process showed to be very effective in the recovering of polyols from PU rigid foam residues, once the process is fast, relatively low cost and produces a final product with equivalent quality of a conventional polyol. The higher functionality and OH number of the recovered polyol brings to the final foam superior mechanical properties. The presence of secondary products like primary amines generated in the process could be noticed by the increase in the reactivity of the formulations using the recycled polyol, although this fact was proved to be manageable through adjustments in the aminic catalyst add to the formulations.

This paper looks at Texas tort law reform to make claims regarding the relationship between Texas tort reform and damages recovered. Starting with reform in 1977, Texas has passed 15 pieces of legislation that, in principle, restrict the damages plaintiffs recover. Most empirical analyses have focused primarily on analyzing behavior resulting from the tort reform. In other cases, research has looked at the impact the most recent reform has had on damages recovered in medical malpractice lawsuits. This paper is the first to study the impact of Texas tort law reform on damages recovered while looking at the entirety of recent law reform in the state. Specifically, I test the impact of the 15 different laws on total allocated loss, economic loss, and noneconomic loss recovered in all cases from 1988-2012. My findings suggest that caps on medical liability damages are successful at decreasing damages recovered when the cap is geared at either noneconomic damages, or a total damage figure that excludes punitive damages. This suggests that future caps on medical liability damages should explicitly cap either economic or noneconomic damages. Next, the results imply that caps on punitive damage legislature were most successful when using specific value caps paired with an evidence standard—caps of this nature decreased total damages by 28% in 1987 and 85% in 1995. Finally, an introductory legislation restricting the use of joint and several liability in cases when plaintiffs had little guilt was successful, it decreased total damages by 18.6%. This was followed by three failed attempts to impact the application of joint and several liability where the guilt threshold was higher, suggesting that joint and several liability is rarely used if the plaintiff has substantial guilt.

This dissertation is available for free download through the University of Arizona library and the author's web site.Since Argentina's economic collapse of 2001, workers who occupied abandoned and bankrupt businesses and put them back into operation as cooperatives have attracted increasing attention on the part of academic researchers and other disaffected workers. This dissertation reviews the political economic contexts in which these "recovered businesses" were established, reviews the dynamics of social movements involved, and considers the Argentine recovered business phenomenon from three analytical perspectives: 1) Marxist poltical economy; 2) Neo-institutional analysis (drawing on the work of Ostrom); and 3) Sociospatial subjectivity (with particular reference to Butler, Lefebvre, and Bourdieu). The author, through these analyses, proposes a theory of the "industrial commons" and considers the potential for expansion and contraction of recovered business movements as their protagonists struggle to resist reterritorialization by forces associated with the state and the capitalist marketplace. Observations made by the author are supplemented by numerous quotations drawn from interviews conducted with Argentine recovered business workers in 2008.Key conclusions include the recognition that social and spatial changes have accompanied the expropriation of private workplaces and their conversion to cooperatives, that these changes may create contexts for the reproduction of cooperative values, and that the new political economic subjects produced through these processes may help to secure the long term viability and growth of not only recovered businesses, but a newly emerging "self-managed workers" movement, as well.

Research in our laboratory has demonstrated blocked and recovered memories within the context of a controlled experiment. The comparative memory paradigm allows for comparisons of recovered memories, continuous memories, and false memories. Additional research in our laboratory has shown two distinct types of memory errors; semantic based errors which occur due to pre-existing category knowledge, and episodic based errors in which the source of details (list members) are misattributed. Independently, these two lines of research have illuminated basic memory processes, however, they have not been combined previously. That is, the experiments in the present study explore the susceptibility of recovered memories to semantic and episodic based errors relative to continuous memories. Experiment 1 replicated the large blocking and recovery effects previously found by our laboratory. Additionally, it demonstrated that recovered memories were no more prone to semantic based errors than were continuous memories. These errors occurred very infrequently despite the use of materials chosen specifically to induce such errors. Experiment 2 again replicated the large blocking and recovery effects. The equivalent low rate of semantic based errors was also replicated. However, Experiment 2 also revealed that recovered memories were more susceptible to episodic based errors than were continuous memories. This was especially true when the memory block occurred in an interference treatment condition. Finally, post-recall source recognition tests failed to improve memory accuracy. In fact, numerically both semantic based and episodic based errors increased on the source recognition test relative to the cued recall test. Findings are discussed in relation to the source monitoring and fuzzy-trace theories of memory as well as the legal and clinical recovered memory controversy.

The purpose with this report was to investigate the possibilities for smaller district heating plants to use recovered wood waste (RT-flis) as fuel. A smaller district heating plant in the north of Sweden (Sorsele värmeverk AB) was the main study object. To be able to incinerate this fuel there are a number of requirements that need to be fulfilled according to the law. In addition to these requirements, the incineration of this fuel also needs to be profitable. The results for this study were obtained through interviews, investigations of the incineration laws and the fuel supply, as well as an analysis of the opinions occurring within the personnel of the heating plants. The results show that the possibility to incinerate RT-flis depends on the appropriate technology; the possibility to fulfill the requirements of the law, as well as it has to be profitable. All these parameters are in close relation to each other. Whether it is technologically possible to use RT-flis largely depends on the construction and technology of the heater, which affects the possibility to fulfill the requirements on, for example, air emissions. Economically, main issues include investments into measuring equipment, but also the accessibility of fuel. The most important aspect is the quality of the fuel (e.g., contaminations).

Research in our laboratory has demonstrated blocked and recovered memories within the context of a controlled experiment. The comparative memory paradigm allows for comparisons of recovered memories, continuous memories, and false memories. Additional research in our laboratory has shown two distinct types of memory errors; semantic based errors which occur due to pre-existing category knowledge, and episodic based errors in which the source of details (list members) are misattributed. Independently, these two lines of research have illuminated basic memory processes, however, they have not been combined previously. That is, the experiments in the present study explore the susceptibility of recovered memories to semantic and episodic based errors relative to continuous memories. Experiment 1 replicated the large blocking and recovery effects previously found by our laboratory. Additionally, it demonstrated that recovered memories were no more prone to semantic based errors than were continuous memories. These errors occurred very infrequently despite the use of materials chosen specifically to induce such errors. Experiment 2 again replicated the large blocking and recovery effects. The equivalent low rate of semantic based errors was also replicated. However, Experiment 2 also revealed that recovered memories were more susceptible to episodic based errors than were continuous memories. This was especially true when the memory block occurred in an interference treatment condition. Finally, post-recall source recognition tests failed to improve memory accuracy. In fact, numerically both semantic based and episodic based errors increased on the source recognition test relative to the cued recall test. Findings are discussed in relation to the source monitoring and fuzzy-trace theories of memory as well as the legal and clinical recovered memory controversy.

Many studies into emotional labor are constrained by a capitalist paradigm, where emotional labor is performed within corporate organizations with hierarchical divisions of labor. Using the case of Hotel BAUEN, this paper considers emotional labor in different organizational and relational context: a worker-owned and worker-recovered business in Argentina. Drawing on ethnographic observations in Hotel BAUEN, this paper shows how service work is structured in the cooperative hotel. Instead of doing emotional labor in the traditional “service triangle,” worker-owners provide services in a “cooperative dyad” without the oversight of a boss. This structural difference has both organizational and relational implications for the business. First, worker-owners provide a variety of services to a broad set of customers. Second, the processes of autogestión (self-management) rely on workers’ emotional labor to cultivate lateral workplace relations through self-management. Ultimately, within the cooperative service workplace, emotional labor functions differently than the literature would suggest. Rather than reproduce social inequalities, workers use emotional labor to generate capital and sustain an organization that seeks to reduce inequality. / text