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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.
151

The relationship between the five-factor model and individualism/collectivism among South African students

Vogt, Liesl Therese 03 October 2008 (has links)
The Five-Factor Model (FFM) of personality is one of the prominent models in contemporary psychology and defines personality in terms of five broad factors, namely, Neuroticism, Extraversion, Openness to Experience, Agreeableness, and Conscientiousness. Recent research, however, questions the applicability of the FFM in non-Western cultures, suggesting that it is not exhaustive enough and that it does not account for some other personality factors, most notably Individualism/Collectivism. Therefore, this study investigated whether the FFM of personality is related to Individualism/Collectivism in a sample of South African students. A total of 176 questionnaires were completed by students from the University of the Witwatersrand. The questionnaire contained the individualism/collectivism (INDCOL) scales and the Basic Traits Inventory (BTI) which is a South African instrument based on the FFM. Results indicate that there were no significant relationships between the five factors and Individualism/Collectivism. In addition no significant difference was found between race and the five factors and Individualism/Collectivism. There were also no significant differences between home language and the five factors and Individualism/Collectivism.
152

A Multi-level Model for Analysing Whole Genome Sequencing Family Data with Longitudinal Traits

Chen, Taoye 24 April 2013 (has links)
Compared to microarray-based genotyping, next-generation whole genome-sequencing (WGS) studies have the strength to provide greater information for the identification of rare variants, which likely account for a significant portion of missing heritability of common human diseases. In WGS, family-based studies are important because they are likely enriched for rare disease variants that segregate with the disease in relatives. We propose a multilevel model to detect disease variants using family-based WGS data with longitudinal measures. This model incorporates the correlation structure from family pedigrees and that from repeated measures. The iterative generalized least squares (IGLS) algorithm was applied to estimation of parameters and test of associations. The model was applied to the data of Genetic Analysis Workshop 18 and compared with existing linear mixed effect (LME) models. The multilevel model shows higher power at practical p-value levels and a better type I error control than LME model. Both multilevel and LME models, which utilize the longitudinal repeated information, have higher power than the method that only utilize data collected at one time point.
153

Mentalisation in Anorexia Nervosa and disordered eating

Watkins, Hannah January 2016 (has links)
Background: It is posited that attachment difficulties in infancy may result in reduced mentalisation capacity (understanding self and others’ subjective thoughts/mental processes), leading to potentially deleterious psychopathological outcomes such as eating disorders. The exact nature of the relationship between mentalisation and eating disorders/disordered eating is unclear however. Objectives: A systemic review examined whether those with Anorexia Nervosa (AN) experience mentalisation deficits compared to those without EDs. An empirical study, examining the link between mentalisation and disordered eating (DE) in an adolescent sample, was conducted to assess whether borderline trait features mediated the relationship between the two constructs. Method: A systematic search of 6 databases was conducted, and articles were assessed against predetermined inclusion/exclusion criteria. Included articles were assessed against 14 quality criteria and study findings were reported. For the empirical study, 162 participants aged 12-18 completed a questionnaire pack including mentalisation, borderline traits, impulsivity, emotion dysregulation and depression scales, and sociodemographic questions. Results: Results from 10 articles indicated those with AN may experience subtle mentalisation deficits, particularly in recognising negative emotions in others. Mentalisation ability may also vary according to interpersonal context. Mediation analyses found mentalisation ability exerted a significant effect on DE indirectly through borderline trait features, and partially through emotion dysregulation, but not impulsivity. Conclusion: More robust empirical studies are required in order to assess the relationship between mentalisation and AN. Findings regarding the link between mentalisation, borderline traits and DE may further aid psychological assessment/treatment. Therapies where the main focus is improving mentalisation capacity may be useful.
154

Análise dos Elementos Traços e relação com o Meio Ambiente e a Saúde: vulnerabilidade do sítio arqueológico pré-histórico Araras– Marabá/PA. / Analysis of trace elements and relation with the environment and health: Vulnerability archaeological site Araras - Maraba / PA.

Prado, Marlon 21 August 2013 (has links)
Submitted by admin tede (tede@pucgoias.edu.br) on 2016-09-08T17:55:28Z No. of bitstreams: 1 MARLON PRADO.pdf: 3843693 bytes, checksum: 7943b6b676b446982baf8e85bd353125 (MD5) / Made available in DSpace on 2016-09-08T17:55:28Z (GMT). No. of bitstreams: 1 MARLON PRADO.pdf: 3843693 bytes, checksum: 7943b6b676b446982baf8e85bd353125 (MD5) Previous issue date: 2013-08-21 / The object of this work is the Araras archaeological site, located in Pará State, municipality of Maraba / PA. Archaeology is an interdisciplinary science requires contributions from other sciences to be able to contribute to the study of prehistoric societies, considering how tiny is the quantity and quality of the materials produced by these people. The health study of pre-Columbian populations is still quite restricted to findings of bones and coprolites, so this work is to provide another means of studying the health of these people, through analysis of trace elements. The objective of this work is to conduct chemical analysis multi element in soil samples, prehistoric pottery and water from the site Araras, pointing to possible diseases in the affected population that lived in this area around 400-500 AP. For the field study, we performed a multistage methodology advocated by Redman (1975). In laboratory tests, we used the Methodology multi acidic by ICP to obtain the amount of the trace elements, Fe, Cu, Zn, Se, Mo, Co, Cr and Mg concentration was found to evaluate and make parallel with dietary intakes of recommended allowance (RDA) for each element. / O objeto de estudo deste trabalho é o sitio arqueológico Araras, situado no Estado do Pará, município de Marabá/PA. A arqueologia sendo uma ciência interdisciplinar necessita de aportes de outras ciências para poder contribuir para os estudos das populações pré-históricas quanto históricas, haja vista o quão é pouca a quantidade de tipos de vestígios dos materiais produzidos por esses povos que restaram nesta área de estudo. O estudo da saúde de populações pré-colombianas, ainda é bastante restrito a achados de sepultamentos ou coprólitos, sendo assim este trabalho vem fornecer mais um meio de estudo a saúde desses povos, por meio de analises dos elementos traço. O objetivo deste trabalho consiste em realizar análise química multielementar em amostras de solo, cerâmica pré-histórica e água do sítio arqueológico Araras, para apontar possíveis doenças acometidas na população que viveu nesta área por volta de 400 a 500 A.P.. Para o estudo de campo, foi realizada a metodologia de multiestágio preconizada por Redman (1975). Nas análises laboratoriais, utilizou-se a metodologia multiácida por ICP, para obter a quantidade dos elementos traço, Fe, Cu, Zn, Se, Mo, Co, Cr e Mg para avaliar a quantidade encontrada e fazer o paralelo com as ingestões Dietéticas de Recomendadas (Recommended Dietary Allowances) para cada elemento.
155

The association between perceived stress, coping styles and personality traits in a sample of Psychology Honours students

Nel, Sanche January 2016 (has links)
Magister Psychologiae - MPsych / Literature identified Psychology students to be vulnerable to the stress associated with professional postgraduate studies and the nature of multiple processes. Less research has been conducted on Honours students as a cohort. The present study attempted to examine the associations between personality traits, perceived stress and coping styles in a sample of Honours students and post-Honours interns enrolled at a historically disadvantaged university. The present study was a cross-sectional internet survey including four instruments: the Brief COPE questionnaire (coping styles), the Perceived Stress Scale (subjective stress), the Big 5 Personality Survey (BFI-10) (personality traits) and a demographic questionnaire. All participation was voluntary and general principles of ethics were adhered to. The data was analysed using frequencies, correlation matrices, coefficients of determination and and regression. Findings indicated medium levels of perceived stress in this sample including contextual factors like gender, age and race. The B.Psych students reported reduced ranges on perceived stress compared to Honours students. Personality profiles indicated the four highest ranked traits (agreeableness, conscientiousness, openness and extraversion) closely banded. Neuroticism was ranked substantially lower in this sample. More adaptive coping styles like (planning, religion, active coping, acceptance etc.) were used than maladaptive coping styles. Associative relationships were indicated between demographic variables and coping, personality traits and perceived stress respectively. Race, Gender, relationship status, registration status and Age was found to correlate significantly with the three core constructs (perceived stress, coping and personality traits). Findings indicated predictive relationships between combinations of coping styles which could significantly predict perceived stress. Maladaptive coping significantly predicted perceived stress controlling for adaptive coping (e.g. emotion-focused coping and problem-focused coping).
156

Autistic characteristics in adults with epilepsy

Wakeford, SallyAnn Rose January 2012 (has links)
The prevalence of autism spectrum disorders [ASD] in epilepsy is approximately 20%-32%, with previous research reporting high rates of under-diagnosis of ASD in epilepsy. Current psychological assessments were adapted to provide epilepsy-specific measures of behaviour, which increased validity by addressing specific methodological problems highlighted by several researchers. The initial experiments provided a comprehensive investigation of autistic traits and characteristics in a heterogeneous group of adults with epilepsy without any ASD diagnosis to quantify the extent to which autistic characteristics are related to seizure activity. Adults with epilepsy showed higher autistic traits and impaired social responsiveness while systemizing and empathising abilities remained intact. Further, autistic traits and impaired social responsiveness increased again during seizure activity. Social responsiveness positively correlated with anti-epileptic drug [AED] control. Adults with epilepsy and seizure remission demonstrated significant improvements in restricted, repetitive behaviours compared to adults with current epileptic seizures. Together, these results demonstrate a relationship between seizure activity and autistic characteristics, and are consistent with previous suggestions that AEDs may mask autistic characteristics. The impaired social skills and communication are consistent with research suggesting that the pathogenesis of epilepsy may disrupt social functioning. However, whether this can be directly attributed to social cognitive deficits remains uncertain. The main research addresses this uncertainty by conducting three experiments to assess the Somatic Marker Hypothesis and the mechanisms which underpin it. The rationale is to establish whether this is a valid explanatory model for disrupted neurobiological factors implicated in social cognitive processing. This hypothesis is appropriate for investigating adults with epilepsy, some who may have developed typical social abilities in early life before epilepsy onset. Results from the IOWA Gambling Task demonstrated that adults with epilepsy had impaired decision making abilities compromising somatic marker formation, crucial for social cognition. However, this deficit occurred in the absence of other socio-emotional and memory impairments. In conclusion, adults with epilepsy have a higher rate of autistic characteristics, and their social difficulties may be associated with compromised somatic marker formation. Future research needs to determine the heritability of these autistic traits and characteristics.
157

Genetic studies of cardiometabolic traits

Riveros Mckay Aguilera, Fernando January 2019 (has links)
Diet and lifestyle have changed dramatically in the last few decades, leading to an increase in prevalence of obesity, defined as a body mass index >30Kg/m2, dyslipidaemias (defined as abnormal lipid profiles) and type 2 diabetes (T2D). Together, these cardiometabolic traits and diseases, have contributed to the increased burden of cardiovascular disease, the leading cause of death in Western societies. Complex traits and diseases, such as cardiometabolic traits, arise as a result of the interaction between an individual's predisposing genetic makeup and a permissive environment. Since 2007, genome-wide association studies (GWAS) have been successfully applied to complex traits leading to the discovery of thousands of trait-associated variants. Nonetheless, much is still to be understood regarding the genetic architecture of these traits, as well as their underlying biology. This thesis aims to further explore the genetic architecture of cardiometabolic traits by using complementary approaches with greater genetic and phenotype resolution, ranging from studying clinically ascertained extreme phenotypes, deep molecular profiling, or sequence level data. In chapter 2, I investigated the genetic architecture of healthy human thinness (N=1,471) and contrasted it to that of severe early onset childhood obesity (N=1,456). I demonstrated that healthy human thinness, like severe obesity, is a heritable trait, with a polygenic component. I identified a novel BMI-associated locus at PKHD1, and found evidence of association at several loci that had only been discovered using large cohorts with >40,000 individuals demonstrating the power gains in studying clinical extreme phenotypes. In chapter 3, I coupled high-resolution nuclear magnetic resonance (NMR) measurements in healthy blood donors, with next-generation sequencing to establish the role of rare coding variation in circulating metabolic biomarker biology. In gene-based analysis, I identified ACSL1, MYCN, FBXO36 and B4GALNT3 as novel gene-trait associations (P < 2.5x10-6). I also found a novel link between loss-of-function mutations in the "regulation of the pyruvate dehydrogenase (PDH) complex" pathway and intermediate-density lipoprotein (IDL), low-density lipoprotein (LDL) and circulating cholesterol measurements. In addition, I demonstrated that rare "protective" variation in lipoprotein metabolism genes was present in the lower tails of four measurements which are CVD risk factors in this healthy population, demonstrating a role for rare coding variation and the extremes of healthy phenotypes. In chapter 4, I performed a genome-wide association study of fructosamine, a measurement of total serum protein glycation which is useful to monitor rapid changes in glycaemic levels after treatment, as it reflects average glycaemia over 2-3 weeks. In contrast to HbA1c, which reflects average glucose concentration over the life-span of the erythrocyte (~3 months), fructosamine levels are not predicted to be influenced by factors affecting the erythrocyte. Surprisingly, I found that in this dataset fructosamine had low heritability (2% vs 20% for HbA1c), and was poorly correlated with HbA1c and other glycaemic traits. Despite this, I found two loci previously associated with glycaemic or albumin traits, G6PC2 and FCGRT respectively (P < 5x10-8), associated with fructosamine suggesting shared genetic influence. Altogether my results demonstrate the utility of higher resolution genotype and phenotype data in further elucidating the genetic architecture of a range of cardiometabolic traits, and the power advantages of study designs that focus on individuals at the extremes of phenotype distribution. As large cohorts and national biobanks with sequencing and deep multi-dimensional phenotyping become more prevalent, we will be moving closer to understanding the multiple aetiological mechanisms leading to CVD, and subsequently improve diagnosis and treatment of these conditions.
158

Ecology of grazing lawns on tallgrass prairie

Shaffer, Monica January 1900 (has links)
Master of Science / Department of Biology / David C. Hartnett / A key feature of many grass-dominated ecosystems is the formation of grazing lawns, distinct patches characterized by intense grazing by mammalian herbivores and a dense short-statured grass canopy. A central concept of grazing lawns is the positive feedbacks between grazing animals and the grass resource. Intraspecific morphological plant trait changes and differences in plant species composition could both or individually play a role in the differences in characteristics of grazing lawns and neighboring tallgrass swards. I studied grazing lawns in North American tallgrass prairie to: a) test the ‘architectural shift hypothesis’ where continued grazing leads to changes in plant architecture resulting in more efficient foraging for grazers, creating a positive feedback that increases grazing and b) examine soil resource (nutrient and water) availability and grass nutritive quality on and off lawns to test the nutrient- and water-based pathways for grazing lawn maintenance. In a separate study (not reported here), we a) examined plant community structure on and off lawns to determine whether species composition differences account for the distinct grazing lawn characteristics and b) assessed effects of grazing lawn formation on tallgrass prairie plant species diversity. Several differences in morphological traits between dominant grasses on grazing lawns and tallgrass swards support the architectural shift hypothesis. For Sorghastrum nutans, Dichanthelium oligosanthes, and Pascopyrum smithii, leaf-to-stem ratio was twice as high on grazing lawns compared to surrounding matrix tallgrass vegetation and tiller branching was higher and culm internode lengths were shorter on grazing lawns for these species. However, Andropogon gerardii traits did not differ between grazing lawns and tallgrass vegetation. For all four species, above-ground tiller biomass and number of below-ground buds were both higher on grazing lawns. Overall, these morphological responses resulted in a higher grass canopy density (forage biomass per unit canopy volume) on grazing lawns and this increased grass canopy density in turn results in higher grazer foraging efficiency by increasing the amount of forage intake per bite and per unit time. D. oligosanthes, P. smithii, and S. nutans plants on grazing lawns had a significantly lower carbon-to-nitrogen ratio and higher nitrogen content than plants in the matrix tallgrass vegetation, while A. gerardii showed no significant difference in nitrogen content or in carbon-to-nitrogen ratio between grazing lawns and surrounding matrix tallgrass vegetation. With regards to the total grass canopy (all grass species combined), nitrogen content was significantly higher on grazing lawns compared to tallgrass vegetation for all three field seasons, 2016, 2017, and 2018. All measured soil nutrients, ammonium, nitrate, phosphorus, and sodium, were significantly higher on grazing lawns compared to soils of surrounding tallgrass swards, while water content showed no significant difference between grazing lawns and surrounding tallgrass vegetation. The results of this study strongly indicate that developmental and morphological shifts result in increased forage density and increased grazing efficiency on grazing lawns and that the frequent and intense activities of large grazers result in increased plant nitrogen content and lower C:N ratios in grasses on tallgrass prairie grazing lawns. Thus, at least two different mechanisms, plant architectural shifts and the nutrient-based pathway could both contribute to the positive feedbacks that encourage further grazing on lawns and grazing lawn maintenance on tallgrass prairie.
159

Influence of orthodontic caregiver behaviour on the perceived satisfaction of patients during orthodontic treatment.

Du Raan, Frederick Johannes January 2014 (has links)
Magister Scientiae Dentium - MSc(Dent) / Influence of orthodontic caregiver behaviour on the perceived satisfaction of patients during orthodontic treatment. Dr. F.J. du Raan M.Sc. (Orthodontics) thesis, Department of Orthodontics, University of the Western Cape. In this thesis I interviewed patients that are busy with orthodontic treatment, as well as those that have undergone orthodontic treatment at the department of Orthodontics at the University of the Western Cape, with the aid of four questionnaires. Patients completed questionnaires to provide general and demographic information, quantify their satisfaction with the orthodontic treatment process, their perception of the orthodontic clinician's behavioural traits and lastly they completed the NEO-FFI personality questionnaire to determine their own personality profile. All these questionnaires were used in previous studies, or they were slightly modified to be applicable to orthodontics. The information gained was used to determine if there are correlations between the patient’s perceived satisfaction of the treatment process with patient specific treatment variables (as acquired from the General information and Demographics Questionnaire ), demographic factors, clinician's behavioural traits and patient specific personality traits and any combination of the above mentioned. We wanted to determine which behavioural traits of the orthodontic caregiver influences the perceived satisfaction with the treatment to the greatest extent. Furthermore, we wanted to determine if certain personality traits of the patients would influence their perceived satisfaction with the treatment process or their perception of the clinician's behavioural traits. The only aspect from the General Information and Demographics Questionnaire that had any correlation to satisfaction with the treatment process or the perception of the clinician's behavioural traits, was whether the patient was treated by a single registrar or multiple registrars. Patients treated by multiple clinicians had a lower average score for satisfaction and orthodontist behaviour. Results from the study shows that all the clinician's behavioural traits do have statistically significant influence on the perceived satisfaction with the treatment process, but certain behavioural traits have a greater influence. Result showed Empathy and Care to have the strongest influence on perceived satisfaction, whereas Motivation has the lowest influence. The NEO-FFI personality questionnaire was used to register each patient's personality profile. Scoring for the following personality traits created the personality profile: Neuroticism, Extraversion, and Openness to Experience, Conscientiousness and Agreeableness. Patient personality profiles were shown to have no significant influence on the patient's perceived satisfaction with the treatment process.Neuroticism was shown to have a weak negative correlation with the Professionalism sub-category of the Orthodontic Clinician Behaviour Questionnaire. Conscientiousness has been shown to have a weak positive correlation with all categories of the Orthodontic Clinician Behaviour Questionnaire It is put forth by the researcher that more time and effort has to be put into improving all aspects of the clinician's behaviour, as it will positively influence the perceived satisfaction of the orthodontic treatment process.Even though there are no significant correlations, patients needs to be screened to determine their personality profiles, as this may lead to slight improved scoring on certain behavioural aspects which may in turn lead to greater patient satisfaction. It may be especially worthwhile to recognise the neurotic patient and treat them on a more personal level, as this may improve their overall satisfaction.
160

Genetics of health and lameness in dairy cattle

Obike, Onyemauchechi Mercy January 2009 (has links)
For the modern dairy cow, advances in genetics and breeding for productivity has resulted in an increasing incidence of health disorders and reduced longevity. One of the most important health problems is lameness, which has led to significant economic, production and welfare consequences. A reduction in lameness will improve the economic future of the dairy industry through increased profitability and decreased welfare-related problems. Although positive attempts have been made by researchers and the industry towards improving lameness, it has remained a persistent ailment for dairy farmers. Further analysis of the genetic and environmental factors influencing lameness is warranted so that selection indices and management practices can be modified leading to improved health and welfare of the dairy cow. Several factors that cause dairy cow lameness have been implicated. I reviewed previous studies on these causative factors as well as the association between lameness, longevity and fertility. It has also been suggested that lameness affects milk production of dairy cows, but reports on the association between lameness and daily milk yield of cows have varied among researchers. Using locomotion score data on 248 cows from the Langhill herd, I investigated the relationship between locomotion score which has a high genetic correlation with lameness and various explanatory variables and also the association between daily milk yield and lameness. The study revealed that the most significant factors affecting locomotion are management regime (high concentrate feed and all year indoor housing; low concentrate feed and outdoors in summer) and time of year when cows are locomotion scored. It also showed that lameness adversely affects the milk yield of later lactation cows, and that high yielding cows are more susceptible to lameness. Housing environment plays a significant role in the health and welfare of dairy cows. With national type evaluation records, I estimated the association between housing systems and lameness-related type traits as well as genetic parameters for the locomotion traits. The analysis indicated that cows kept at pasture had favourable linear and composite type trait scores compared with cows in cubicles, straw yards and slatted floors or loafing yards. Locomotion score had strong genetic and phenotypic correlations with the leg and feet composite. Bone quality, which is a new trait in the UK type classification scheme, was moderately heritable (0.23) and had a moderate and positive genetic association with locomotion and leg and feet composite. This suggests that breeding for flatter, more refined bones could reduce locomotion disorders and help improve the longevity of the dairy cow. Analysis of national data again showed reduced incidence of digital dermatitis (DD) for cows at pasture and those with flatter, more refined bones, higher locomotion score and better leg and feet composite. Estimates of genetic parameters indicated heritable variation of DD among cows and moderate genetic associations between DD and production traits and longevity. Incorporating DD in future selection indices will be useful for increased productive life. Using random regression, I analysed changes in type traits associated with lameness (locomotion, rear legs, side view, foot angle and leg and feet composite) in relation to time (months) that cows had spent in cubicles before being classified. The general trend supported the fact that cubicle housing is unfavourable to these traits. There was significant evidence of a genotype x environment interaction, suggesting variation between bulls in the sensitivity of their daughters to cubicle housing with time.

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