This thesis studies the optimization of a variable speed, three blade, horizontal-axis wind turbine. The design parameters considered are the rotor diameter, hub height and generator capacity. The levelized cost of energy and simple payback are the figures of merit being minimized. Blade element momentum theory is used to calculate the power produced by the wind turbine rotor. Increasing the rotor diameter increases the power delivered to the generator at all wind speeds up to the limit of generator capacity. Increasing the generator capacity raises the limit on maximum power output. Increasing the hub height of a wind turbine increases power output due to the higher wind speeds at increased heights. However, all of these design changes involve an increase in capital cost. Furthermore, wind characteristics vary between wind resources. Therefore, the optimal wind turbine design will change depending on the wind resource. The model developed in this thesis is used to minimize the levelized cost of energy for various wind resources. The results of this study provide a guideline for the optimum wind turbine design in various wind resources. The model is also used to compare the difference between minimizing the levelized cost of energy and minimizing simple payback of a wind turbine located off the coast of Georgia. Simple payback is calculated by considering not only the total annual electricity produced and capital cost of the turbine but also the revenue the turbine will generate. Revenue is calculated from a time-dependent valuation of electrical power. The results of this study show that minimizing levelized cost of energy and minimizing simple payback result in the same optimum design for this particular site. The results show, however, that using a time-dependent valuation of electricity results in a different simple payback than when an average value of electricity is used.

The seasonal and diurnal concentrations of atmospheric carbonyls were measured by the LpDNPH-Cartridge and the microcomputer air sampling device at Nan-Chie and Hsiung-Kong sites in Kaohsiung area. Then, factor analysis and absolute principal component analysis were also used to determine the source apportionment in Kaohsiung area. Total concentrations of carbonyls were higher in Summer than in winter at Nan-Chie and Hsiung-Kong sites. Measurements showed that the highest carbonyls were formaldehyde and acetaldehyde, due to the fact that photochemical activities are stronger in summer than in winter. The concentrations of total carbonyls, formaldehyde, acetaldehyde were showed similar diurnal variations, that highest concentrations were found in the morning and noon, then drop down at afternoon and increased at night. Due to the fact that photochemical activities and vehicle exhausts. C1-C3 ratio indicated the local participation of anthropogenic hydrocarbons was important in the production of carbonyls in the Kaohsiung area. C1/C2 was highest in the summer than in the winter, that photochemical activities cause highest concentrations of formaldehyde, especially in the summer noon. The results of factor analysis and absolute principal component analysis showed that the primary pollution sources at Nan-Chie were traffic exhausts (diesel and gasoline vehicle) and stationary sources (petrochemical and food industry) and restaurant emissions, and the primary pollution sources at Hsiung-Kong were traffic exhausts (diesel and gasoline vehicle), stationary emissions (metal assembly and petrochemical industry) and restaurant emissions.

Relationship conflict is robustly linked to negative physiological responses that have serious implications for partners’ overall physical health. The link between relationship conflict and physiological reactivity, however, has been studied almost exclusively in a laboratory setting. The first aim of this study was to assess the link between conflict and physiological function in couples’ home environments. Newlywed spouses reported occurrences of marital conflict in a daily diary and concurrently provided morning and evening saliva samples for the calculation of daily diurnal cortisol slopes. Spouses experienced less steep (i.e., less healthy) diurnal cortisol slopes on days of greater marital conflict. The second aim of this study was to examine whether spouses’ connections with close others outside their marriages (i.e., quantity and quality of perceived network support) moderate physiological responses to marital conflict. Whereas the quantity of network support did not influence spouses’ responses to conflict, the quality of spouses’ network support attenuated the association between daily marital conflict and diurnal cortisol. Specifically, whereas those spouses who were less satisfied with their network support experienced less steep diurnal cortisol on days of greater marital conflict, those spouses who were more satisfied with their network support exhibited no effects of daily marital conflict on diurnal cortisol. Implications for maintaining quality social relationships outside a marriage are discussed. / text

Intensity and types of land use have changed rapidly in the last century and in north-western Alberta this has coincided with the decline of Wapiti River watershed Arctic Grayling (<italic>Thymallus arcticus</italic>) populations. Data on diurnal dissolved oxygen (DO), chemical and physical stream habitat data were collected in nine sub-watersheds of the Wapiti River with historically abundant Arctic Grayling populations. Levels and fluctuations of DO and temperature were related to the status of populations; five of the nine streams had higher temperatures and lower DO during summer, anoxic conditions during winter and extirpated populations. Amount of disturbed land and road density within sub-watersheds were inversely related to DO levels and population status. Cumulative effects modelling suggests a possible mechanism for these relationships is increased phosphorous runoff, leading to impaired habitat. These relationships and thresholds may be used as a management tool to maintain or restore Arctic Grayling and other stream fishes.

No description available.

Women seem to be largely protected against certain ‘welfare disorders’ such as cardiovacular disease and osteoporosis, during their fertile years.The metabolic changes observed during women’s non-menstrual states, i.e. during pregnancy, after the menopause and during use of oral contraceptives, indicate the importance of sex steroids and an undisturbed biological rhythm. Treatment with monophasic, combined oral contraceptives constitutes a model for the non-cyclic state.Growth hormone (GH) is a pituitary hormone that has major metabolic effects. The pattern of GH exposure to the target organ is of vital importance for the effects and changes in rhythm could possibly induce metabolic changes.Growth hormome, cholecystokinin (CCK), osteocalcin and angiotensinogen were used as markers for metabolic effects and the concentrations in serum were recorded in women during non-menstrual states. The clinical material comprised a total of 60 women: 18 healthy non-pregnant, 25 pregnant, one lactating woman and 16 postmenopausal women. Using a portable pump and a non-thrombogenic venous catheter, blood samples could be collected at 30-min intervals during 24-h periods. Furthermore, the effects of estrogen and GH in the regulation of angiotensinogen were investigated in an experimental model in the rat.Oral contraceptives were found to alter the secretion of GH towards a pattern of lower and more frequent peaks, though the total amount secreted during 24 h was unchanged. Oral contraceptives seem to induce a suppression of the 24-h concentrations of CCK, which may be important with respect to weight gain in some women. Osteocalcin in serum display a significant circadian variation. This emphasizes the need for careful timing of single point measurements and the value of continuous blood sampling. Oral contraceptives may reduce osteocalcin serum concentrations. The long-term effects on bone are unknown. During late pregnancy osteocalcin levels are extremely low, which could indicate osteoblast inhibition and reduced bone turnover. The mode of GH administration is important for the plasma concentration of angiotensinogen in the non-pregnant rat. Estrogen effects on this protein may be mediated via a modification of GH secretion. Oral contraceptives not only increase angiotensinogen concentrations in serum but also markedly enhance their variability. Further studies are needed to elucidate the relation between the individual pattern of angiotensinogen and hypertension. / <p>S. 1-42: sammanfattning, s. 43-88: 6 uppsatser</p> / digitalisering@umu

Atmospheric inversion has recently become an important tool in estimating CO2 sinks and sources albeit that the existing inversion results are often uncertain and differ considerably in terms of the spatiotemporal variations of the inverted carbon flux. More measurements combined with terrestrial ecosystem information are expected to improve the estimates of global surface carbon fluxes which are used to understand the relationships between variabilities of the terrestrial carbon cycle and anomalies of climatic factors. Inversions using more observations have often been hampered by the intense diurnal variations of CO2 concentrations at continental sites. Diurnal variations of the surface flux are included with atmospheric boundary dynamics in order to improve the atmospheric inversion accuracy. Modeling experiments conducted in this study show that inverse estimates of the carbon flux are more sensitive to the variation of the atmospheric boundary layer dynamics than to the diurnal variation in the surface flux. It is however generally better to consider both diurnal variations in the inversion than to consider only either of them. Forest carbon dynamics is closely related to stand age. This useful terrestrial ecosystem information has been used as an additional constraint to the atmospheric inversion. The inverse estimates with this constraint over North America exhibit an improved correlation with carbon sink estimates derived from eddy-covariance measurements and remotely-sensed data, indicating that the use of age information can improve the accuracy of atmospheric inversions. Terrestrial carbon uptake is found mainly in northern land, and a strong flux density is revealed in southeastern North America in an improved multi-year inversion from 2002 to 2007. The global interannual variability of the flux is dominated by terrestrial ecosystems. The interannual variabilities of regional terrestrial carbon cycles could be mostly explained by monthly anomalies of climatic conditions or short-time extreme meteorological events. Monthly anomalies of the inverted fluxes have been further analyzed against the monthly anomalies of temperature and precipitation to quantitatively assess the responses of the global terrestrial carbon cycle to climatic variabilities and to determine the dominant mechanisms controlling the variations of terrestrial carbon exchange.

Atmospheric inversion has recently become an important tool in estimating CO2 sinks and sources albeit that the existing inversion results are often uncertain and differ considerably in terms of the spatiotemporal variations of the inverted carbon flux. More measurements combined with terrestrial ecosystem information are expected to improve the estimates of global surface carbon fluxes which are used to understand the relationships between variabilities of the terrestrial carbon cycle and anomalies of climatic factors. Inversions using more observations have often been hampered by the intense diurnal variations of CO2 concentrations at continental sites. Diurnal variations of the surface flux are included with atmospheric boundary dynamics in order to improve the atmospheric inversion accuracy. Modeling experiments conducted in this study show that inverse estimates of the carbon flux are more sensitive to the variation of the atmospheric boundary layer dynamics than to the diurnal variation in the surface flux. It is however generally better to consider both diurnal variations in the inversion than to consider only either of them. Forest carbon dynamics is closely related to stand age. This useful terrestrial ecosystem information has been used as an additional constraint to the atmospheric inversion. The inverse estimates with this constraint over North America exhibit an improved correlation with carbon sink estimates derived from eddy-covariance measurements and remotely-sensed data, indicating that the use of age information can improve the accuracy of atmospheric inversions. Terrestrial carbon uptake is found mainly in northern land, and a strong flux density is revealed in southeastern North America in an improved multi-year inversion from 2002 to 2007. The global interannual variability of the flux is dominated by terrestrial ecosystems. The interannual variabilities of regional terrestrial carbon cycles could be mostly explained by monthly anomalies of climatic conditions or short-time extreme meteorological events. Monthly anomalies of the inverted fluxes have been further analyzed against the monthly anomalies of temperature and precipitation to quantitatively assess the responses of the global terrestrial carbon cycle to climatic variabilities and to determine the dominant mechanisms controlling the variations of terrestrial carbon exchange.

The sex hormone testosterone supports male reproduction. However, testosterone is hypothesized to suppress immune activity, resulting in a tradeoff between energetic investment in reproductive effort and immune function. The Immunocompetence Handicap Hypothesis (ICHH) therefore argues that testosterone-linked masculine traits honestly signal health status to prospective mates, as only uninfected males should be able to maintain high testosterone levels. Still, this proposed tradeoff remains poorly tested among human men, especially among natural fertility populations experiencing high infectious disease burdens. This dissertation therefore tested the ICHH among indigenous Shuar men of Amazonian Ecuador. Specifically, this project examined testosterone variation patterns and assessed how male investment in reproductive effort is associated with reproductive success and immune function. The first study tested testosterone level variation among Shuar men in relation to body composition, age, and style of life factors. This study demonstrated that age and BMI interactions shape testosterone levels in complex ways, such that the relationship between body composition and testosterone profile varies throughout the life course. The second study investigated whether individual reproductive success was significantly influenced by masculine trait development and parasite load. These results failed to support the hypotheses that masculine traits increased reproductive success or honestly signaled lack of parasitic disease. Instead, a significant positive association was observed between a composite score of masculine traits and Ascaris lumbricoides infection load; suggesting that male investment in reproductive effort may increase parasitic infection risk. The final study assessed whether testosterone levels were negatively associated with four measures of immune function (parasite load, C-Reactive Protein [CRP], Immunoglobulin-G [IgG], and Immunoglobulin-E [IgE]). Testosterone levels were inversely associated with CRP levels and a positive relationship between testosterone levels and Trichuris trichiura infection load was documented, suggesting increased investment in reproductive effort may suppress some aspects of immune function and increase parasite burden. Overall, these studies fail to support the ICHH, but do indicate a context-dependent tradeoff between energetic investment in male reproductive effort and some aspects of immune function; thereby demonstrating complex interactions between physical characteristics, physiological processes, and immune activity in human men. This dissertation includes unpublished, co-authored material.

In this thesis, we study the effect of diurnally- and seasonally-varying forcing on the global circulation of planetary atmospheres explored within a large parameter space. This work focusses on studying the spacial and spectral energy budgets across a large range of planetary parameters as well as the momentum transfer as a response to diurnal and seasonal effects. We simulate planetary atmospheres using PUMA-GT, a simple GCM co-developed for this work, that is forced by a semi-grey two-band radiative-convective scheme, dissipated by Rayleigh friction and allows for temporally varying insolation. Our parameter regime includes the variation of the planetary rotation rate, frictional timescale in the boundary layer, the thermal inertia of the surface and the atmosphere, as well as the short-wave optical thickness. We calculate the energy transfer in Martian atmosphere to have a reference case of an atmosphere that is subject to very strong seasonal and diurnal variation. For this we present the first Lorenz energy budget calculated from reanalysis data of a non-Earth planet. A comparison between Martian and Earth atmosphere reveals a fundamentally different behaviour of the barotropic conversion term in the global mean. A significant impact of the thermal tide can be discerned in the generation of eddy kinetic energy, especially during global dust storms. Our study of seasonal variation reaffirms previous work that the equatorial super-rotating jet in the slow-rotating regime is arrested for strong seasonal variation. We find a novel explanation as to why the Titan atmosphere is able to maintain super-rotation despite strong surface seasonality; for non-zero short-wave absorption in the atmosphere the mechanism that hinders equatorial super-rotation is weakened. Diurnally-varying forcing can significantly enhance the equatorial super-rotation in cases with non-zero short-wave absorption. In our simulations this enhancement is maintained by a convergence of vertical momentum flux at the equator. Efforts to identify the atmospheric waves involved in this enhancement point towards thermally-excited gravity waves.