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The increasing dependence on amphibian captive breeding programs to support at-risk populations has led to growth in the application of assisted reproductive technologies (ART) to aid with the management of decreasing population density and genetic diversity. Already the integration of ART within these programs has led to monumental successes and shows great promise as a means to augment amphibian breeding efforts when natural breeding has low success. The focus of this project was to continue the optimization of ART to aid in making these technologies more widely applicable. Specific objectives include developing a framework that can be used to standardize follicular grading of oocytes through ultrasound assessments, demonstrating how advantageous routine sonography assessments are in providing insight into the female reproductive cycle in captive amphibians, and determining the differences in offspring growth and development between Ambystoma tigrinum larvae produced through in-vitro fertilization with either freshly collected or frozen-thawed sperm.

Black women have higher incidence rates of aggressive subtypes of endometrial cancer and worse survival rates compared with white women. The overall incidence rate has been increasing in black women and, accounting for their higher prevalence of hysterectomy, may be higher than in white women. Exposures related to obesity and metabolic disorders, reproductive factors, and use of exogenous hormones have been associated with endometrial cancer risk in prior studies. However, because these studies have primarily included white women, little is known about these associations in black women. We therefore examined associations of endometrial cancer with previously identified risk factors in 47,555 participants in the Black Women’s Health Study, a prospective cohort of U.S. black women. Study 1 focused on anthropometric and metabolic factors. After adjustment for age at menarche, parity, menopausal status, smoking, and use of oral contraceptives, estrogen-only female menopausal hormones (FMH), and estrogen plus progestin FMH, self-reported body mass index (BMI), BMI at age 18, greater weight gain since age 18, and diagnosis of diabetes were positively associated with endometrial cancer risk. Self-reported diagnosis of hypercholesterolemia and hypertension were not independently associated. In study 2, we examined associations with reproductive factors. Endometrial cancer incidence was higher among women with early age at menarche, a history of infertility, a greater number of lifetime menstrual cycles, and diagnosis of polycystic ovary syndrome. Parity and early age at first birth were associated with lower risk, while a greater number of births and breastfeeding were not associated with risk. Positive associations with late age at menarche among premenopausal women and longer duration of breastfeeding among obese women require confirmation in other studies. In study 3, we examined the associations of endometrial cancer with exogenous hormone use. The inverse association with oral contraceptive use was primarily among women who used oral contraceptives for ≥5 years. Incidence was higher among current users of estrogen-only and estrogen plus progestin FMH, and ever users of progestin only FMH. Lower risk was observed among former users of estrogen plus progestin FMH. / 2019-04-30

Building an efficient and robust robot that does not use appendages for locomotion requires inspiration and a thorough understanding of the working principles of limbless animals’ locomotion. In these animals, the passive properties of their morphology and material allow them to dwell in complex terrains at different animals’ scales by using only a simple mode of locomotion, i.e., undulatory locomotion. A better understanding of these animals can inspire efficient locomotion strategies and lead to multi-gait terrain adaptation that exploits their physical intelligence. This study endeavors to model undulatory locomotion in various environments and study the effect of endogenous and exogenous dynamics in limbless bodies. First, undulatory locomotion is modeled analytically using the Lagrangian mechanics approach in a dry frictional environment. A discrete multi-bar system is set to get the propulsive force through frictional anisotropy. The system is then non-dimensionalized to determine the factors representing material and environmental properties. The principal components of the model are body stiffness, internal damping, moment of inertia, and frictional anisotropy. Simulations showed the interdependence of these quantities to achieve the desired speed. The results also highlighted the interdependence of endogenous and exogenous dynamics to achieve different locomotion gaits. Swimming, crawling, and polychaete-like locomotion are characterized based on stiffness factor, frictional factor, and frictional coefficient ratio. The model is validated by inputting the required parameters of the corn snake from the literature. Then undulatory locomotion is modeled in a viscous environment, and the results are compared with the dry environment. It is found that the optimum weight of dry and viscous frictional factors can be found in a hybrid environment to achieve better speed performance. Finally, the experimental validation is carried out in a dry friction environment. The results from experimental and physical models are compared. The physical robot is a wheel-based modular system with flexible joints moving on different substrates. The influence of the spatial distribution of the body stiffness on the speed performance is also explored. Findings suggest that the environment affects the performance of undulatory locomotion based on the body stiffness distribution. Although quantitatively the stiffness varies with the environment, we obtained a qualitative constitutive law for all environments. Specifically, we expect the stiffness distribution to exhibit either an ascending-descending or an ascending-plateau pattern along the length of the object, from head to tail. Furthermore, undulatory locomotion showed sensitivity to contact mechanics: solid-solid or solid-viscoelastic contact produced different locomotion dynamics. Our findings elucidate how terrestrial limbless animals achieve undulatory locomotion performance by exploiting the passive properties of the environment and the body. Application of the obtained results can lead to better-performing long-segmented robots exploiting the aptness of passive body dynamics and the characteristics of the environment where they need to move.

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<p dir="ltr">The objective of the experiments conducted for this dissertation was to investigate the effects of exogenous enzymes on nutrient digestibility for broiler chickens and growing pigs. These experiments covered the effects of phytase, protease, and carbohydrases on the nutrient availability of various diet types and ingredients, as well as evaluations of regression methods for determining ingredient energy values. One study investigated a factorial of phytase and dietary phytate levels on the ileal digestibility of amino acids (AA) and phosphorus (P) for broilers and pigs. The results of these experiments indicated that phytase improved the ileal digestibility of P (P < 0.05) and all AA (P < 0.05) for broilers regardless of the dietary phytate level, and the ileal digestibility of P (P < 0.05) and many economically important AA (P < 0.05) for pigs. This study did not reveal any significant interactions between phytase and dietary phytate, but there were a number of numerical differences in the relative effect of phytase in the two diet types. In a subsequent experiment the effects of a factorial of phytase and protease on ileal P and AA digestibility were evaluated for growing pigs. Similarly to the first study, phytase was shown to improve the ileal digestibility of P (P < 0.05) and a majority of AA (P < 0.05). There were limited main effects of protease, however, it was found to decrease the digestibility of Lys, Met, and Thr (P < 0.05). There were a number of significant quadratic interactions (P < 0.05) of protease within phytase level, where the necessary concentration of protease to elicit positive effects was dependent on phytase inclusion. The next study evaluated the effects of two carbohydrase blends on the ileal AA digestibility and energy values of soybean meal. Both enzyme blends elicited modest improvements in the ileal and total tract digestibility of energy, but there were limited effects on the energy values of the test diets. Both enzyme blends improved the apparent metabolizable energy of soybean meal, but the blend with lower activity and no protease inclusion produced the greater results with an improvement of 15.2%. These enzyme blends resulted in the improved ileal digestibility of nearly all AA from soybean meal for broilers. The last study was a validation of the three-point model for the regression method against a four-point model over both the same test ingredient inclusion range or smaller range. This evaluation used both canola meal and wheat as test ingredients to evaluate if changes in dietary energy or protein levels affect the results of this method, which are representative of both cereal grains and protein concentrates, respectively. The results indicated that there was no difference in the three and four-point models for either ingredient as long as the overall range of test ingredient concentration was the same in both models. This proved more important for canola meal, as it was more susceptible to problems with the estimates or variability based on changes in inclusion. Based on the results of these experiments, it is clear that phytase can improve the AA digestibility for both pigs and chickens, but care must be taken when combinations are made with protease. These data indicate that the use of carbohydrase blends can improve the nutrient availability of soybean meal, and this could have significant implications in diet formulation. Lastly, the use of the three-point model for the regression method is appropriate, but is dependent on the inclusion level of the test ingredient test ingredient.</p>

Atherosclerotic and restenotic lesions develop as a result of an excess inflammatory response to vascular injury. Glucocorticoid hormones have widely-recognised anti-inflammatory and anti-proliferative properties which appear to make them ideal candidates for inhibition of vascular lesion development. Indeed, administration of glucocorticoids to experimental animals does inhibit the growth of vascular lesions in some models. In addition, glucocorticoids are currently being trialled clinically as anti-restenotic agents. However, glucocorticoid excess in patients, either as a result of Cushing’s syndrome or chronic steroid therapy, is associated with enhanced CVD risk. Therefore, the effects of glucocorticoids on vascular lesion development remain imperfectly understood. The overall objective of these studies was to explore the influence of endogenous and exogenous glucocorticoids on vascular lesion development using murine models of atherosclerosis (ApoE-/- mice fed a “western” diet) and neointimal hyperplasia (wireinduced femoral artery injury). The work described in this thesis addresses the hypothesis that glucocorticoids are pro-atherogenic, yet anti-restenotic. Mice were bilaterally adrenalectomised to investigate the role of endogenous glucocorticoids on vascular lesion development. Removal of the adrenal glands had no influence on atherogenesis or neointima development. The influence of exogenous glucocorticoids on lesion development was assessed by orally administering dexamethasone (0.1 or 0.8mg/kg/day). Atherosclerotic lesion burden was augmented by dexamethasone administration. Conversely, fibro-proliferative neointimal proliferation was inhibited by dexamethasone. However, this effect was obscured by thrombotic lesion development. It was proposed that this thrombotic effect is attributable to increased plasminogen activator inhibitor-1 (PAI-1), which was tested using PAI-1 deficient mice. Although PAI-1 was found to mediate the systemic pro-thrombotic effect of dexamethasone, it is not required for the enhanced development of thrombotic lesions at the site of intra-luminal injury. These results suggest that physiological levels of endogenous glucocorticoids play a limited role in vascular lesion development. Conversely, although exogenous glucocorticoids inhibit fibro-proliferative intimal hyperplasia, they appear to have significant detrimental influences on lesion development, augmenting atherosclerosis and inducing thrombotic neointimal lesion formation following vascular injury. Further research is therefore required to improve the cardiovascular outcome of patients requiring glucocorticoid therapy and for the use of glucocorticoids as antirestenotic agents.

RNA-Sequencing (RNA-Seq) has become one of the most widely used techniques to interrogate the transcriptome of an organism since the advent of next generation sequencing technologies [1]. A plethora of tools have been developed to analyze and visualize the transcriptome data from RNA-Seq experiments, solving the problem of mapping reads back to the host organism's genome [2] [3]. This allows for analysis of most reads produced by the experiments, but these tools typically discard reads that do not match well with the reference genome. This additional information could reveal important insight into the experiment and possible contributing factors to the condition under consideration. We introduce PARSES, a pipeline constructed from existing sequence analysis tools, which allows the user to interrogate RNA-Sequencing experiments for possible biological contamination or the presence of exogenous sequences that may shed light on other factors influencing an organism's condition.

Underground mining of the Kiirunavaara iron mineralization is causing large-scale deformation of the hangingwall of the orebody. To understand and possibly predict future deformation, a structural model of the hanging wall and a good understanding of the petrophysical and mechanical properties of the constituent rocks is necessary. This thesis presents results from the study of Anisotropy of Magnetic Susceptibility (AMS), magneto-mineralogy, fracture frequency (F/m), rock quality (RQD), rock strength (Point Load) and P-wave velocity and anisotropy of the rocks from the hanging wall, as well as seismic reflection surveying and gravity modelling. The results are combined into a structural model of the hanging wall and further used for analysis of the correlation between petrophysical and rock mechanical parameters.In total, 76 samples from 12 outcrops and 295 samples from three drillcores in the hanging wall have been included in the AMS study. Axial and diametrical P-wave velocity was measured on 25 water-saturated samples and 156 samples were used for the Point Load tests. F/m and RQD data for the drillcores already existed. The drillcores are located along the eastern end of the seismic profiles and consist of both crystalline and sedimentary rocks.A high degree of magnetic anisotropy observed in the crystalline rocks indicates a low degree of metamorphism. AMS data also indicates the presence of a magnetic foliation in the rocks. The dip of the magnetic foliation plane (F) and the degree of magnetic anisotropy (Pj) measured in samples from outcrops was plotted as iso-maps and shows that both F and Pj decreases towards the east, which was confirmed by data from the drillcores. The decrease in both parameters is primarily a reflection of a change in rock type, but is also changing within the crystalline rock sequence.A good correlation (r > 0.6) between Pj, and F and RQD, and F and F/m was observed in one drillcore for both crystalline and sedimentary rocks; and between the shape parameter (T) and F/m in crystalline rock in another drillcore. This suggests the AMS parameter may be used as an indicator of rock mechanical properties. AMS data was also correlated to joint strike orientations and it was concluded that AMS can also be used to predict joint orientation.Two parallel reflection seismic profiles were shot within the town of Kiruna i order to locate deformation zones and lithological boundaries in the hangingwall. No deformation zones were found, but five seismic reflectors corresponding to five lithological boundaries were located, and their strike and dip calculated. The result of the seismic survey was used to constrain the gravity model, as was density measurements of 230 samples from the drillcores. The gravity model has a depth of three km, and indicates that the crystalline rock in the hanging wall can be separated into two parallel N-S trending blocks. / Godkänd; 2011; 20111021 (maimos); DISPUTATION Ämnesområde: Tillämpad geofysik/Applied Geophysics Opponent: PhD Satu Mertanen, Geological Survey of Finland, Åbo Ordförande: Professor Sten-Åke Elming, Institutionen för samhällsbyggnad och naturresurser, Luleå tekniska universitet Tid: Måndag den 19 december 2011, kl 10.00 Plats: F531, Luleå tekniska universitet