Digitized by Kansas Correctional Industries

Call number: LD2668 .T4 1956 B38 / Master of Science

This thesis studies the relationship between type Ia supernovae (SNe Ia) and their host galaxies. The sample consists of 527 SNe Ia with redshift z<0.09 discovered by the Palomar Transient Factory (PTF). We obtained high-quality photometric and spectroscopic data of the host galaxies and determined their stellar mass M_stellar, star formation rate (SFR), gas-phase/stellar metallicity, stellar age and SN offset. In the first part of the analysis, we compare the SN Ia photometric properties to the host parameters. Strong correlations between the SN Ia light-curve width (stretch) and the host age/mass/metallicity are found: fainter, faster-declining events tend to be hosted by older/massive/metal-rich galaxies. There is also some evidence that redder SNe Ia explode in higher metallicity galaxies. SNe Ia in higher-mass/metallicity galaxies also appear brighter after stretch/colour corrections than their counterparts in lower mass hosts, and the stronger correlation is with gas-phase metallicity suggesting this may be the more important variable. We also compare the host stellar mass distribution to that in galaxy targeted SN surveys and the high-redshift untargeted Supernova Legacy Survey (SNLS). The difference between each stellar mass distribution can be explained by an evolution in the galaxy stellar mass function, coupled with a SN delay-time distribution proportional to t^-1. Finally, we found no significant difference in the mass-metallicity relation of our SN Ia hosts compared to field galaxies, suggesting any metallicity effect on the SN Ia rate is small. In the second part of the analysis, we compare the SN spectral features to the host parameters. We find that SNe Ia with higher Si ii λ6355 velocities tend to explode in more massive galaxies. We study the strength of the high-velocity component of the Ca ii NIR absorption, and find that SNe Ia with a stronger high-velocity component are preferentially hosted by galaxies with a low M_stellar, a blue colour, and a high SFR, and are therefore likely to arise from the youngest progenitor systems. When combined with other studies, our results support the scenario that these high-velocity features are related to an interaction between the SN ejecta and a circumstellar medium (CSM) local to the SN.

There are substantial data exploring the link between religiosity and health, yet there is no consensus regarding the appropriate measurement tool for assessing religiosity in health psychology settings. The purpose of this study was to identify a set of items that could serve as a reliable and valid proxy measure of religiosity. Participants included 251 (M=19.02; range = 17-25) young adults who completed self-report measures of religiosity (Intrinsic-Extrinsic/Revised, Quest Scale, Faith Maturity Scale), psychological distress (SCL-90-R), and personality (NEOPI-R). Individual item pools for religiosity were developed by identifying significant correlations between each of the religiosity measures and the SCL-90-R items. Exploratory factor analyses and item-level analyses were conducted and convergent and discriminant validity were examined for each proposed measure. A group of items were identified that were associated with previously validated measures of religiosity. These religiosity measures were also associated with the personality domains of Openness to Experience and Agreeableness but were not associated with Neuroticism. There was insufficient evidence, however, to conclude that the proposed measures could serve as true proxy measures of religiosity as they were more strongly associated with Neuroticism than the religiosity measures from which they were derived. The results of this study underscore the importance of the religiosity construct to health-related outcomes, yet much work remains to delineate the optimal means of measuring the construct and the specific pathways by which religiosity may exert its influence on both mental and physical health.

Denna rapport baseras på experimentella försök där det undersökts hur pelletdensiteten påverkar utsläpp av kolmonoxid (CO) och stoft vid småskalig förbränning. I en testpanna med ansluten pelletsbrännare testades tre densiteter: låg, mellan och hög. Testerna uppdelades i tre faser i form av uppstart, kontinuerlig drift och släckning. Tre repetitioner gjordes på varje fas och för varje bränsle med undantag av släckning där endast en mätning per bränsle gjordes. Resultatet visade generellt en tydlig skillnad i CO-emission. Oberoende av densitet var CO-emissionerna mycket större vid uppstart och släckning än vid kontinuerlig drift. Avseende densitet gavs ett entydigt resultat där den lägsta pelletdensiteten gav högre stoftemissioner under alla driftsförhållanden. Skillnaden mellan de två pelletssorterna av högre densitet är däremot inte signifikant. För CO-emissioner sågs vid uppstartsfasen en tydlig trend mellan minskad pelletdensitet och ökade CO-emissioner. Vid kontinuerlig drift sågs emellertid det omvända: hög densitet gav högre CO-emissioner, varvid mellandensiteten gav något lägre CO-emissioner och låg densitet gav lägst CO-emissioner. Om skillnaden är uteslutande beroende på pelletdensiteten är svårt att säga. Ytterligare försök rekommenderas för att avgöra den exakta inverkan av pelletarnas densitet.

The purpose of the study was to psychometrically evaluate the Revised Janis and Field Scale using the rasch model. The model is a measurement model often used to develop and improving composite measures. Quantitative content analysis was also used in the study. After the two analyses were conducted the problematic items were examined, where an interpretative perspective was applied to try to explain why some questions didn’t seem to work as intended. The other purpose of the study was to examine if emotional and cognitive components need to be treated as separate variables when studying self-esteem. The data collection was administrated at Karlstad University in April of 2014. In total 225 respondents participated in the survey, of whom 140 were women and 85 were men. Based on the rasch model, the instrument did not seem to measure self-esteem in an acceptable manner. There were also major problems with the content of the questions and how they were structured. It is concluded that the instrument should not be used for research purposes. Based on the analyses it was not possible to determine if it’s necessary to distinguish between emotional and cognitive components of self-esteem. It requires more analysis, based on more reliable instruments in the future. / Syftet med studien var att utvärdera mätinstrumentet Revised Janis and Field Scale med hjälp av psykometriska analyser baserat på raschmodellen. Raschmodellen är en mätmodell som används inom olika discipliner vid utveckling och granskning av mätinstrument. Därutöver genomfördes här även en kvantitativ innehållsanalys. När de två analyserna var genomförda granskades problematiska frågor, där ett tolkningsperspektiv anlades för att försöka förklara varför vissa frågor inte verkade fungera som avsett. Avsikten med studien var även att undersöka om emotionella och kognitiva beståndsdelar bör hanteras som separata variabler. Datainsamlingen ägde rum vid Karlstads universitet under april månad 2014. Totalt deltog 225 respondenter i undersökningen, 140 kvinnor respektive 85 män. Baserat på raschanalysen verkar inte instrumentet mäta självkänsla på ett godtagbart sätt. Därutöver finns problem med de ämnen som frågorna behandlar och hur frågorna samt svarsalternativen är formulerade. Bedömningen gjordes baserat på analyserna att instrumentet inte bör användas i vetenskapliga sammanhang. Avslutningsvis var det inte möjligt att bekräfta om det är nödvändigt att särskilja mellan emotionella och kognitiva beståndsdelar ur självkänslan utifrån de analyser som genomförts här. Det krävs att fler analyser genomförs i framtiden och att dessa bygger på mer stabila mätinstrument för att uppnå det syftet. / Self-esteem, The Self, Revised Janis and Field Scale, Rasch analysis

This study investigates the effects of fire on the chemistry and flux of precipitation diverted to the forest floor as stemflow and throughfall by observing the impact of the June 2013 Thompson Ridge Wildfire in the Jemez River Basin of New Mexico. The loss of canopy cover from wildfire drastically modifies landscapes and alters ecosystems as fire replaces leafy canopies with charred branches and trunks, changes soil composition and erosion processes, and affects hydrologic flow paths and water chemistry. In order to track these changes, throughfall and stemflow collectors were installed beneath burned and unburned canopies in two catchments impacted by the Thompson Ridge Fire. Throughfall, stemflow, and open precipitation samples were analyzed for major cations, anions, dissolved inorganic and organic carbon, trace metals, and rare earth elements to determine how fire affects the chemical composition of the precipitation that interacts with burned canopies. Precipitation samples collected from both burned and unburned sites during the 2014 summer monsoon season show variations across burn severity, specifically in calcium, strontium, phosphate, and dissolved inorganic carbon concentrations, and across collector type with stemflow concentrations generally higher than throughfall and open precipitation concentrations. A stem count model was used to determine tree density for individual plots and catchments from LiDAR images taken before the 2013 fire. The stem count model was used to upscale event and monsoon season solute fluxes from plot to catchment scale. Higher nutrient concentrations combined with higher volumes of precipitation diverted as stemflow in burned forests have a multiplicative effect resulting in greater nutrient fluxes via stemflow creating nutrient hot spots surrounding burned tree trunks. Upscaling these plot scale concentrations and solute fluxes allows this study to represent changes to an entire catchment and quantify effects of wildfire on chemical loads and water chemistry.

The increasing complexity of oil and gas reservoirs has led to the need of a better understanding of the processes governing the rock properties. Traditional theoretical and empirical models often fail to predict the behavior of carbonates, tight gas sands and shale gas, for example. An essential part of the necessary investigation is the study of the phenomena occurring at the pore scale. In this direction, the so-called digital rock physics is emerging as a research field that offers the possibility of imaging the rock pore space and simulating the processes therein directly. This report describes our work on developing algorithms to simulate viscous and electric flow through a three dimensional Cartesian representation of the porous space, such as those available through X-ray microtomography. We use finite differences to discretize the governing equations and also propose a new method to enforce the incompressible flow constraint under natural boundary conditions. Parallel computational codes are written targeting performance and computer memory optimization, allowing the use of bigger and more representative samples. Results are reported with an estimate of the error bars in order to help on the simulation appraisal. Tests performed using benchmark samples show good agreement with experimental/theoretical values. Example of application on digital modeling of cement growth and on multiphase fluid distribution are also provided. The final test is done on Bentheimer, Buff Berea and Idaho Brown sandstone samples with available laboratory measurements. Some limitations need to be investigated in future work. First, the computer potential fields show anomalous border effects at the open boundaries. Second, a minor problem arises with the decreased convergence rate for the velocity field due to the increased number of operations, leading to the need of a more sophisticated preconditioner. We intend to expand the algorithms to handle microporosity (e.g. carbonates) and multiphase fluid flow. / text

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