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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.
111

Structural characterisation of novel poly-aryl compounds

Khashoqji, Moayad January 2016 (has links)
Poly-aryl, also known as polyphenylene compounds are a class of dendrimer, which contain a large number of aromatic rings. They are of interest because they display restricted rotation of their stearically congested aromatic rings. These extended structures have the potential to act as precursors for even larger aromatic systems and have many applications including electronic devices, drug delivery and catalysis. A total of 23 novel poly-aryl compounds have been examined using single crystal X-ray diffraction and a number of structural patterns have emerged. Six of the compounds contain alkynes and it has been observed that their conformation is governed by a combination of conjugation between the alkyne and aryl groups and inter-molecular interactions. In the more extended poly-aryl compounds steric congestion rules out any possibility of conjugation between the rings and their conformation is governed by intra-molecular non-bonded interactions in the core of the molecules and by inter-molecular interactions in their periphery. Where possible, solution NMR measurements were carried out on the poly-aryl compounds and confirmed that the solution structures are in agreement with those obtained from individual crystal.
112

Um teste computadorizado para a avaliação de visão de cores em crianças e sujeitos não-verbais baseado no teste de discriminação de cores de Mollon-Reffin / A computer-controlled color vision test for children and non-verbal subjects based on the Mollon-Reffin color discrimination test

GOULART, Paulo Roney Kilpp 16 December 2008 (has links)
Submitted by Cleide Dantas (cleidedantas@ufpa.br) on 2014-05-06T12:57:48Z No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Tese_TesteComputadorizadoAvaliacao.pdf: 2426574 bytes, checksum: 1a7bce3f4ebea8a25887a50dba8215c1 (MD5) / Approved for entry into archive by Ana Rosa Silva (arosa@ufpa.br) on 2014-05-12T15:35:48Z (GMT) No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Tese_TesteComputadorizadoAvaliacao.pdf: 2426574 bytes, checksum: 1a7bce3f4ebea8a25887a50dba8215c1 (MD5) / Made available in DSpace on 2014-05-12T15:35:48Z (GMT). No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Tese_TesteComputadorizadoAvaliacao.pdf: 2426574 bytes, checksum: 1a7bce3f4ebea8a25887a50dba8215c1 (MD5) Previous issue date: 2008 / CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico / O presente estudo visou garantir condições favoráveis para a avaliação de discriminação de cores em crianças, por meio de uma adaptação no modo Trivector do teste de discriminação de cores de Mollon-Reffin. Como a tarefa original, de indicar a abertura do C de Landolt, se mostrou pouco intuitiva para crianças pequenas, o alvo foi mudado para uma área colorida aproximadamente quadrada e a resposta requerida passou a ser tocar no alvo. O modo de teste Trivector mede os limiares de discriminação de cor ao longo de três linhas de confusão características das três formas variantes de visão de cor humana: protan-, deutan- e tritan-. O Experimento I avaliou a concordância entre o teste original e a versão adaptada, com 29 sujeitos adultos com visão de cor normal. A comparação dos limiares obtidos com as duas versões, por meio do método de avaliação de concordância de Bland-Altman, mostrou boa concordância entre as versões. No Experimento II, o teste adaptado foi aplicado em 25 crianças de 2 a 7 anos, usando técnicas de treino operante para estabelecer e manter o desempenho dos sujeitos. Os limiares diminuíram progressivamente acompanhando o aumento na idade. Os limiares protan- e deutan- foram consistentemente menores que os limiares tritan-, um padrão que já havia sido observado com adultos no teste original. Os resultados demonstram que, feitas as adaptações necessárias, o teste é adequado para a avaliação da discriminação de cor em crianças pequenas e pode ser uma ferramenta útil para a identificação das variações da visão de cor durante o desenvolvimento, bem como para a aplicação em outras populações humanas e, inclusive, outros primatas. (CNPq, FINEP). / The present study aimed at providing conditions for the assessment of color discrimination in children using a modified version of the Trivector mode of the Mollon-Reffin color discrimination test. Since the task of indicating the gap of the Landolt C used in that test proved counterintuitive and/or difficult for young children to understand the target stimulus was changed to a square patch of color the subjects were asked to touch. The Trivector test measures color discrimination for the protan, deutan and tritan confusion lines. Experiment I sought to evaluate the correspondence between the CCT and the child-friendly adaptation with adult subjects (n=29) with normal color vision. Comparison of the thresholds obtained with both tests using Bland-Altman statistical methods showed good agreement between the two test versions. Experiment II tested the child-friendly software with children 2 to 7 years old (n=25) using operant training techniques for establishing and maintaining the subjects‟ performance. Color discrimination thresholds were progressively lower as age increased. The protan and deutan thresholds were consistently lower than tritan thresholds, a pattern repeatedly observed in adults tested with the CCT. The results demonstrate that the test is fit for assessment of color discrimination in young children and may be a useful tool for the establishment of color vision thresholds during development, as well as for use with other human populations, as well as with other primate species. (CNPq, FINEP).
113

Proton location in acid center dot center dot center dot pyridine hydrogen bonds of multi-component crystals

Seaton, Colin C. 17 April 2014 (has links)
No / The design of new functional crystalline materials requires an understanding of the factors that control salt and co-crystal formation. These states often only differ in the location of the proton and are influenced by chemical and crystallographic factors. The interaction between a carboxylic acid and a pyridine is a frequently used supramolecular synthon in crystal engineering which can exist as either a co-crystal (CO2H center dot center dot center dot N) or salt (CO2-center dot center dot center dot HN+). The results of a Cambridge Structure Database search indicate that the nature of the functional groups on the pyridine play a stronger role in selection of the phase than those of the acid. However, the nature of the local hydrogen bonding of the interaction also adjusts the potential for proton transfer. This was demonstrated by ab initio modelling of the energy landscape for binary and ternary co-crystals by inclusion of varying components of the local environment.
114

Factors Associated With Adherence to Diabetes Medication Among Individuals With Type 2 Diabetes in Cambridge, Ontario, Canada.

Atekha, Benedict Osamuimen 01 January 2018 (has links)
Although it is known that the prevalence of type 2 diabetes is on the rise in Canada, more information is needed on how well type 2 diabetes patients living in Cambridge, Ontario self-manage their diabetes and what factors influence their adherence to diabetes medication regimens. The objective of this cross-sectional study based on the theory of planned behavior was to determine if there are predictors of adherence to diabetes medications among patients living with type 2 diabetes in Cambridge. The World Health Organization STEPwise Approach to Surveillance was used to collect demographic data. Adherence and diabetes knowledge were assessed with the 8-item Morisky Medication Adherence Scale and the Michigan Diabetes Knowledge Test, respectively. Research subjects were 56 adults recruited through convenience sampling. Predictor variables that were tested included age, gender, level of education, and diabetes education, and the response variable was adherence to diabetes medication. Level of education (p = .001) was the only strong predictor of adherence to diabetes medication in the bivariate logistic regression analysis. In addition, in the multivariate logistic regression analysis, the following combined variables were significantly associated with adherence to type 2 diabetes medication: age and level of education; age and diabetes knowledge; gender and level of education; gender and diabetes knowledge; and level of education and diabetes knowledge. Application of the findings of this study may help to minimize the risk of diabetes-associated complications and improve quality of life for those with type 2 diabetes, thereby reducing type 2 diabetes healthcare costs for patients, insurance payers, and other stakeholders.
115

Investigation into cognitive function in first episode psychosis and chronic schizophrenia patients : an investigation into cognitive deficits associated with first episode psychosis and chronic schizophrenia patients in South Asian and Caucasian populations as assessed by the Cambridge Neuropsychological Test Automated Battery (CANTAB)

Saleem, Majid Mohammed January 2012 (has links)
Rationale Cognitive deficits are now recognised as a major symptom of schizophrenia with a number of studies reporting profound deficits in cognitive function in both chronic and first episode patients. Recent advances in cognitive remediation therapy have provided the opportunity for patients to improve their cognitive function and therefore improve their functional outcome. Aim The aim of the present study was to investigate cognitive deficits using the Cambridge Neuropsychological Test Automated Battery (CANTAB®) in first episode psychosis and chronic schizophrenia patients. In the first episode population the effect of ethnicity on cognition was also examined. In the chronic schizophrenia study comparisons between severity of deficits with first episode psychosis patients were also made. The effects of cognitive remediation therapy were also examined in a sample of first episode patients. Methods A total of 35 patients and 30 healthy controls were recruited into the first episode study, 17 patients and 17 controls into the chronic schizophrenia study and 11 patients into the cognitive remediation study. The first episode psychosis patients were recruited from the Bradford and Airedale Early Intervention Service and the chronic patients from the Leeds Partnership NHS Foundation Trust. The control subjects were matched as closely as possible in terms of intelligence and demographics to the patient groups. The Wechsler Test of Adult Reading (WTAR) was used to estimate subjects pre-morbid IQ. The severity of symptoms was assessed using the Positive and Negative Syndrome Scale (PANSS). All subjects who took part in the study completed a comprehensive battery of neuropsychological tests from the CANTAB®. Patients in the cognitive remediation study participated in group therapy sessions using X-cog®. Results There were no significant differences found between There were no significant differences found between patients and controls in relation to intelligence or demographics in all studies. The effect of ethnicity was shown to be not significant in the first episode study. Results show that patients performed significantly worse than controls across all iv cognitive domains tested in all studies. A correlation between negative symptoms and executive function was found in both first episode and chronic schizophrenia patients. Comparisons between first episode psychosis and chronic schizophrenia patients in cognition showed no significant differences, however significant differences were found in levels of negative symptoms and age between the two groups with chronic patients scoring higher on negative symptoms and being older. In the cognitive remediation study a significant improvement was observed in patients in the domain of executive function and a reduction in negative symptoms following completion of the intervention. Conclusion First episode and chronic schizophrenia patients display significant cognitive deficits across all domains when tested using the CANTAB®. Some of these deficits appear to be independent of the length of the illness but dependent on negative symptoms. This study demonstrates that cognitive deficits exist across all patient groups regardless of age, gender, pre-morbid IQ, years in education and ethnicity. Cognitive remediation therapy has also been shown to be effective in improving cognitive functioning in patients.
116

Clinical differentiation of mental disorders in the eldery : validation of the CAMDEX

Gatten, Shauna L. January 1993 (has links)
The present series of investigations examined the diagnostic accuracy of the Cognitive Examination (CAMCOG) from the Cambridge Mental Disorders of the Elderly Examination (CAMDEX) in the differential diagnosis of various dementing conditions. Specifically, this study examined: (a) the degree to which the CAMCOG would differentiate normal individuals from patients with Alzheimer's Disease (AD) and from those suffering from non-AD dementing conditions, (b) the extent to which the CAMCOG would distinguish between patients suffering from organic dementing conditions, those having functional psychiatric disorders, and normal persons, and (c) whether the CAMCOG would offer an improvement in diagnostic accuracy over a widely used screening instrument (i.e., the Mini-Mental Status Examination, MMSE) when attempting to differentially diagnose dementing patients and normal cohorts.A review of the literature was presented with an emphasis on the difficulties in establishing differential diagnosis, inaccuracies in diagnosis, the importance of improved diagnostic accuracy, and the use of neuropsychological measures in the assessment and diagnosis of patients suffering from dementing illnesses. Further, research relevant to ancillary diagnostic techniques, the various neuropsychologicalapproaches used in evaluating and diagnosing mental disorders in the elderly, and studies investigating the utility of specific cognitive/neuropsychological measures in the differential diagnosis of dementing diseases was presented.The results of these investigations revealed that the CAMCOG provides excellent diagnostic sensitivity and specificity when differentiating normal persons from clinically diagnosed AD patients and when distinguishing between individuals with an organic-dementing condition and normal adults. The CAMCOG was found to be less effective in differentiating AD and non-AD dementia patients and in distinguishing between patients suffering from organic dementia versus specified psychiatric disorders. Finally, the CAMCOG demonstrated a slight improvement in diagnostic accuracy over the Mini-Mental Status Examination. These results were discussed in terms of their support for the utility of the CAMCOG as an excellent screening measure when used to differentiate patients suffering from various dementia-producing disease states and normal persons. / Department of Educational Psychology
117

Model-based approaches to support process improvement in complex product development

Wynn, David Charles January 2007 (has links)
The performance of product development processes is important to the commercial success of new products. The improvement of these processes is thus a strategic imperative for many engineering companies - the aero-engine is one example of a complex product for which market pressures necessitate ever-shorter development times. This thesis argues that process modelling and simulation can support the improvement of complex product development processes. A literature review identified that design process modelling is a well-establishedresearch area encompassing a diverse range of approaches. However, most existing tools and methods are not widely applied in industry. An extended case study was therefore conducted to explore the pragmatic utility of process modelling and simulation. It is argued that iteration is a key driver of design process behaviour which cannot be fully reflected in a mechanistic model. Understanding iteration can help select an appropriate representation for a given process domain and modelling objective. A model-based approach to improve the management of iterative design processes was developed. This approach shows that design process simulation models can support practice despite their limited fidelity. The modelling and simulation framework resulting from this work was enhanced for application to a wider range of process improvement activities. A robust and extensible software platform was also developed. The framework and software tool have made significant contribution to research projects investigating process redesign, process robustness and process optimisation. These projects are discussed to validate the framework and tool and to highlight their applicability beyond the original approach. The research results were disseminated in academia and industry - 72 copies of the software were distributed following requests in the first three months of its release.
118

Demokracie je agon: k Machiavelliho populistickému republikanismu / Democracy is agon: on Machiavelli's populist republicanism

Bíba, Jan January 2013 (has links)
The present dissertation deals with the relationship between democracy and agonism. It attempts to defend the idea that certain problematic aspects of contemporary liberal democracies are not due to their origin primarily in the change of social conditions (the massification of democracy, the growth of complexity in modern societies), that made the original democratic promises unrealizable, but in certain oblivion of the agon. The agon is understood as a constitutive feature of democratic society and its oblivion is seen not to be accidental. To defend this proposition I focuse on an interpretation of the dialogue between populist republicanism (Machiavelli) and elitist republicanism (Guicciardini). This dialogue is usually understood as one of the sources of modern democratic tradition. I try to explain that in Machiavelli's political theory two notions of agonism are present - pragmatic agon that sees conflict as a basis of social cohesion and strategic agon that is described as a ferocious egalitarianism employed by the second class citizens in order to gain equality from the first class citizens. These two forms of agonism are explained to form the axis of Machiavelli's notion of the political and also of a free republic and democracy. Guicciardini's elitist republicanism is shown to stand in opposition...
119

ロバートソンにおける英国正統派経済学の伝統と革新 : 「努力」概念による体系化 / ロバートソン ニオケル エイコク セイトウハ ケイザイガク ノ デントウ ト カクシン : ドリョク ガイネン ニヨル タイケイカ / ロバートソンにおける英国正統派経済学の伝統と革新 : 努力概念による体系化

仲北浦 淳基, Junki Nakakitaura 21 March 2018 (has links)
本研究の目的は,ケンブリッジ学派の経済学者D.H.ロバートソンの経済変動論体系を統一的に理解し,その学史的・現代的意義を再評価することである.ロバートソンが重視した実物的経済変動論の「実物real」とは一体何を指しているのか,という根本的な問いからはじめ,その「実物」が彼の経済変動論体系において有している重要性を明らかにする. / 博士(経済学) / Doctor of Economics / 同志社大学 / Doshisha University
120

Investigating intermolecular interactions motifs in ammonium carboxylate salts

Odendal, James Arthur 12 1900 (has links)
Thesis (MSc (Chemistry and Polymer Science))--University of Stellenbosch, 2009. / ENGLISH ABSTRACT: This thesis reports an in-depth investigation of the intermolecular interaction motifs in secondary, primary and ammonium carboxylate salts. The investigation was conducted using the Cambridge Structural Database (CSD), together with a systematic steric-specific experimental study. The tendency in the literature has been to analyse organic salt crystal structures in terms of hydrogen bonding patterns, almost ignoring cation-anion interactions. This study focuses on the cation-anion interactions in secondary, primary and ammonium carboxylate salts, which have a direct effect on the formation of specific structural motifs. The ideas of ring-stacking and ring-laddering, which arise from the tendency of cations and anions to arrange themselves so as to maximise electrostatic interactions, have been applied to ammonium carboxylate salts. An extensive survey of organic ammonium carboxylate salt structures in the CSD has been carried out. The structural motifs in ammonium carboxylates were investigated, and a set of predictive rules for the pattern of intermolecular interactions in these salts was developed. Using these results, the formation of ring-stacking or ring-laddering in primary ammonium carboxylate salts can be predicted. The results from the CSD survey are discussed in Chapter 3. An experimental study has been carried out, which complements the results obtained from the CSD survey. The experimental study formed 19 novel ammonium carboxylate salts, of which 2 formed hydrates and 2 co-crystals of salts. The experimental results confirm what was found in the CSD survey, and this is discussed in Chapter 4. This study has found that the principle of ring-stacking and ring-laddering can be applied in a general form to the crystal structures of organic ammonium carboxylate salts. The size of the cation and the anion in these salts has a significant effect on the formation of structural motifs in the solid state. Interactions between cation and anion substituents also play an important role in the formation of particular structural motifs in ammonium carboxylate salts. / AFRIKAANSE OPSOMMING: In hierdie tesis word die intermolekulêre interaksie motiewe in die sekondêre, primêre en ammonium karbosilaat soute in-diepte ondersoek. Die studie is gedoen met behulp van die Cambridge Strukturele Databasis (CSD), saam met ‟n sistematiese steriesspesifieke eksperimentele studie. Die neiging in die literatuur is om organiese sout kristal strukture in terme van waterstofbindings patrone te analiseer sonder om katioon-anioon interaksies in ag te neem. Die studie fokus juis op hierdie katioon-anioon interaksies tussen sekondêre, primêre en ammonium karbosilaat soute wat ‟n direkte effek het op die vorming van spesifieke strukturele motiewe naamlik „ring-stacking‟ en „ring-laddering‟ wat hul oorsprong kry vanaf die neiging van katione en anione om hulself op so ‟n wyse te rangskik sodat die elektrostatiese interaksies ‟n maksimum kan bereik, op die ammonium karboksilaat soute. ‟n Volledige ondersoek van ammonium karboksilaat soute in die CSD is gedoen. Die strukturele motiewe in ammonium karboksilaat is ondersoek, en ‟n stel reels wat die patrone van intermolekulêre interaksies in hierdie soute voorspelis ontwikkel. Hierdie resultate kan gebruik word om die vorming van „ring-stacking‟ en „ring-laddering‟ in primêre ammonium karbosilaat soute te voorspel. Die resultate van die CSD ondersoek word bespreek in Hoofstuk 3. ‟n Eksperimentele studie is uitgevoer en die resultate hiervan komplimenteer die resultate van die CSD ondersoek. In die eksperimentele studie is 19 nuwe ammonium karboksilaat soute gekristaliseer, waarvan 2 hidraat-soute en 2 ko-kristal-van-soute is. Die eksperimentele resultate bevestig die bevindings van die CSD ondersoek, en dit word bespreek in Hoofstuk 4. Hierdie studie het gevind dat die beginsel van „ring-stacking‟ en „ring-laddering‟ kan in „n algemene vorm in die kristal strukture van organiese ammonium karboksilaat soute toegepas word. Die grootte van die katioon en anion in hierdie soute het ‟n beduidende effek op die vorming van strukturele motiewe in die vaste toestand. Interaksie tussen die katioon en anioon substituente speel „n belangrike rol in die vorming van spesifieke motiewe in ammonium karbosilaat soute.

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