The aims of this thesis were to investigate whether characteristics associated with animal welfare are genetically and genomically determined by using quantitative and molecular genetic approaches and to develop strategies indicating how these traits could be used in breeding programmes. Two traits that are closely related to animal welfare and associated with high socio-economic values are piglet survival at birth and aggressive behaviour in pigs. Piglet survival traits were analysed based on quantitative Bayesian approaches using phenotypic and pedigree information only, while aggressive behaviour was analysed based on molecular genetic approaches such as genome-wide association studies and genomic selection using additionally a dense panel of single nucleotide polymorphisms (SNP). The latter approach was validated using behavioural traits related to welfare characteristics in a welldocumented mouse data set. Selection for piglet survival at birth is expected to be effective, because all lines and breeds in this thesis showed considerable variation for this trait and relatively high heritabilities, particularly in lines with low average birth weight. Maternal heritabilities of individual birth weight were mostly at moderate magnitude and thus of great interest for selection. The genetic correlations between piglet survival and birth weight indicated that selection for either individual or average birth weight or variation of birth weight within litter would indirectly increase survival. The genetic associations of piglet survival with economically important (re)production traits are of great importance for breeding organisations. Undesirable genetic correlations between piglet survival and (re)production traits were generally of low magnitude, so that simultaneous improvement of all traits could be achieved. A comparison of five breeds and lines showed that differences in genetic parameters between breeds and lines can be substantial and no single selection strategy would be optimal for all. A unique study of a sire and a dam line originating from one breed but selected for more than 25 years with different breeding goals demonstrated how selection pressure can alter the genetic parameters over years. Breeding organisations should therefore consider selection strategies per breed or line individually to achieve maximum overall improvement. This study gives new insight into the use of genomic selection for traits associated with animal welfare. It is one of the first to present estimates for linkage disequilibrium in the pig using a new 60K SNP panel and the first to evaluate the efficiency of genomic selection against aggressive behaviour in pigs. Genomic selection showed a high predictive ability in comparison to traditional polygenic selection. It was especially advantageous for traits with lower heritabilities. In particular in situations where little family information was available, the performance of polygenic selection was low and genomic selection increased the performance considerably. Reducing the number of SNPs did not significantly change the performance of genomic selection. The consistently high performance across models indicates that low-density SNP panels may be sufficient to ensure a high efficiency of genomic selection, thus reducing the high costs associated with genotyping in pig breeding with its short generation interval. To summarize, this thesis has shown how to optimise quantitative and genomic approaches to improve animal welfare related characteristics efficiently in pig breeding programmes.

In later life, adverse life events, disability, health problems, inadequate social support, and personality traits hypothesized to be important risk factors for depression. Sample included 35 older (65-84) physical rehabilitation patients in a large metropolitan hospital. Statistical analysis included Pearson Product Moment correlations and multiple regression results. Perceived physical health, instrumental ADLs, life satisfaction, extraversion, and conscientiousness are inversely related to depressive symptom severity; neuroticism is positively related to depressive symptom severity. Regression models predicted depressive symptom severity, PANAS negative effect and PANAS positive affect. Neuroticism, insrumental ADLs, and age are significant predictors of depressive symptom severity; neuroticism and age are signficant predictors of PANAS negative affect, while extraversion is a significant predictor of PANAS positive affect. Personality factors, level of functioning, and age are important factors relating to mood. Limitations of this study include: small sample size with special characteristics (high level of SES); incomplete personal and family history of psychiatric problems; and lack of clinical comparison sample.

<p>Species invasions are more prevalent than ever before. While the addition of a species can dramatically change critical ecosystem processes, factors that mediate the direction and magnitude of those impacts have received less attention. A better understanding of the factors that mediate invasion impacts on ecosystem functioning is needed in order to target which exotic species will be most harmful and which systems are most vulnerable. The role of invasion on nitrogen (N) cycling is particularly important since N cycling controls ecosystem services that provision human health, e.g. nutrient retention and water quality.</p><p>We conducted a meta-analysis and in-depth studies focused on the invasive grass species, Microstegium vimineum, to better understand how (i) plant characteristics, (ii) invader abundance and neighbor identity, and (iii) environmental conditions mediate the impacts of invasion on N pools and fluxes. The results of our global meta-analysis support the concept that invasive species and reference community traits such as leaf %N and leaf C:N are useful for understanding invasion impacts on soil N cycling, but that trait dissimilarities between invaded and reference communities are most informative. Regarding the in-depth studies of Microstegium, we did not find evidence to suggest that invasion increases net nitrification as other studies have shown. Instead, we found that an interaction between its abundance and the neighboring plant identify were important for determining soil nitrate concentrations and net nitrification rates in the greenhouse. In field, we found that variability in environmental conditions mediated the impact of Microstegium invasion on soil N pools and fluxes, primarily net ammonification, between sites through direct, indirect, and interactive pathways. Notably, we detected a scenario in which forest openness has a negative direct effect and indirect positive effect on ammonification in sites with high soil moisture and organic matter. Collectively, our findings suggest that dissimilarity in plant community traits, neighbor identity, and environmental conditions can be important drivers of invasion impacts on ecosystem N cycling and should be considered when evaluating the ecosystem impacts of invasive species across heterogeneous landscapes.</p> / Dissertation

Les problèmes de conduites (PC) qui surviennent dès l'enfance sont à risque de persistance. Des travaux suggèrent que ce risque est accru lorsque les PC s'accompagnent de traits psychopathiques, opérationnalisés chez l'enfant par des dimensions de dureté-insensibilité, égocentrisme-narcissisme et impulsivitéirresponsabilité. Les travaux sur ces traits se sont cependant centrés sur la dimension de dureté-insensibilité et ne permettent pas d'établir si les trois dimensions des traits psychopathiques offrent une valeur prédictive ajoutée chez des enfants ayant des PC sévères. Cette étude longitudinale a pour objectif principal d'établir la contribution relative des trois dimensions des traits psychopathiques pour prédire l’évolution des PC chez des enfants présentant déjà ces problèmes à l'âge scolaire primaire, et à examiner si ces associations varient selon le genre. Les 213 enfants qui participent à l'étude ont été sélectionnés parmi les élèves de moins de dix ans recevant des services psychoéducatifs et dont les PC atteignaient un seuil clinique. Les analyses de régressions montrent que seule la dimension d'impulsivité-irresponsabilité contribue significativement à prédire les PC trois ans plus tard au-delà de la sévérité initiale des PC et du revenu familial, et ce, uniquement chez les garçons. Les résultats remettent en question l'utilisation de la dimension de dureté-insensibilité pour identifier un sous-groupe d'enfants dont les PC sont persistants, ainsi que la pertinence même des traits psychopathiques pour identifier un tel sous-groupe chez les filles.

More than half of known crime is committed by 5-6% of the criminal population. Who are these people? Research has shown that it is likely that a majority of these individuals are characterized by having a psychopathic personality. Interestingly, research has shown that psychopathic features are not unique to adults. Youths with high levels of psychopathic traits resemble adult psychopaths in that they are the most frequent, severe and aggressive, delinquent offenders. There is less knowledge, however, about the development of these traits in adolescence, and many fundamental questions have yet to be addressed. The aim of this dissertation is to begin to examine a few of these questions, such as: a) the role of parents andtheir behavior in the development of psychopathic personality in adolescence; b) patterns of stability and change in psychopathic traits during adolescence; and c) whether or not subgroups of adolescents with high levels of psychopathic traits can be identified in a normative community sample. Overall, the results reveal that a psychopathic personality profile characterizes a small group of youths at particular risk of negative development. This group, as well as showing high levels of psychopathic traits throughout adolescence, report high levels of delinquent behavior, and also experience dysfunctional relationships with their parents. Further, the results reveal important subgroups of adolescents with high levels of psychopathic traits, much in accordance with the literature on adult psychopaths. Whereas one group expresses the personality style of primary psychopaths, another is more aggressive, impulsive, and anxious than the other. Taken together, the results of this dissertation suggest that some adolescents are at particular risk of future negative development. Implications for theory and practice, and for the directions of future research, are discussed.

In this study an attempt was made to gain insight into the meaning of personality traits and how they can be arranged to build an instrument to be used for rating and selecting agents to sell life insurance.

The purpose of this study was to examine the retrospective perceptions of parent-child relations as measured by the Roe-Siegelman Parent-Child Relations Questionnaire (PCR), personality characteristics as they appear on the Minnesota Multiphasic Personality Inventory (MMPI) and types of crimes of prison inmates, specifically divided into aggressive and non-aggressive crimes.

The study was undertaken to discover if the summer camp experience enhanced personality traits of participants in the camp program. The study was implemented at Greene Family Camp in Bruceville, Texas, during the summer of 1985. Utilized were analyses of variance and two types of factor analyses: principal-components analysis with varimax rotation and principal axis factoring with oblique rotation of factor matrices elicited. Five personality areas were analyzed--sociability, independence, achievement, environmental awareness, and spirituality. Spirituality emerged so strongly that it was removed from further analyses. Remaining personality areas emerged, but groupings of variables, especially those relating to achievement and independence, suggest an inherent commonality among the complex facets of personality. Based on these findings, the researcher recommends further investigation and careful replication.

The purpose of this study is to give the results of a testing program in the low seventh grade of an urban school wherein intelligence, personality, achievement, and socioeconomic tests were given. The primary purpose of the tests was to determine what influence, if any, the environmental factors played in the individual learning process, but attention was given to other phases of the learning process as well.

This study was concerned with analyzing selected Texas school administrators in an attempt to locate intrapersonal patterns of (1) values, (2) leadership traits, (3) personality traits, (4) critical thinking ability, (5) perception, and authoritarianism. A second aspect was correlating these profiles with each other. The study had a threefold purpose. The first was to perform a detailed analysis of school administrators to determine selected intrapersonal patterns. The second was to determine possible relationships between these selected profiles. The third was to generate plausible hypotheses for testing the intrapersonal patterns found and for determining the magnitude of any existing relationships. The case studies revealed the uniqueness of each participant in this study. With the possible exception of one individual, certain weaknesses were evident in each of the participants. Canonical correlation and the Pearson correlation of D matrices determined that a relationship existed between many of the profiles. Eight hypotheses were presented at the close of the study as guides for additional research. The results of this study indicated that further research was justified in these particular areas. The results of this study indicated that intrapersonal patterns existed within school administrators and that these patterns or profiles are related. However, the determination of the magnitude of these relationships was left to additional research.