Heat losses and thermal performance of commercial combined solar and pellet heating systems

Various pellet heating systems are marketed in Sweden, some of them in combination with a solar heating system. Several types of pellet heating units are available and can be used for a combined system. This article compares four typical combined solar and pellet heating systems: System 1 and 2 two with a pellet stove, system 3 with a store integrated pellet burner and system 4 with a pellet boiler. The lower efficiency of pellet heaters compared to oil or gas heaters increases the primary energy demand. Consequently heat losses of the various systems have been studied. The systems have been modeled in TRNSYS and simulated with parameters identified from measurements. For almost all systems the flue gas losses are the main heat losses except for system 3 where store heat losses prevail. Relevant are also the heat losses of the burner and the boiler to the ambient. Significant leakage losses are noticed for system 3 and 4. For buildings with an open internal design system 1 is the most efficient solution. Other buildings should preferably apply system 3. The right choice of the system depends also on whether the heater is placed inside or outside of the heated are. A large potential for system optimization exist for all studied systems, which when applied could alter the relative merits of the different system types.

Cathepsin S as a biomarker of low-grade inflammation, insulin resistance, and cardiometabolic disease risk

Cathepsin S is a protease important in major histocompatibility complex (MHC) class II antigen presentation and also in degrading the extracellular matrix. Studies, most of them experimental, have shown that cathepsin S is involved in different pathological conditions such as obesity, inflammation, atherosclerosis, diabetes, and cancer.    The overall hypothesis of this report is that high levels of circulating cathepsin S, is a biomarker that reflects pathology induced by inflammation and obesity. The overall aim of this report was to investigate possible associations between circulating cathepsin S, inflammation, glucometabolic disturbance, and its associated diseases in the community. As cathepsin S appears to be a novel risk marker for several pathological conditions, we also wanted to examine the effect of dietary intervention on circulating cathepsin S concentrations.    This thesis is based on data from three community-based cohorts, the Uppsala longitudinal study of adult men (ULSAM), the prospective investigation of the vasculature in Uppsala seniors (PIVUS), and a post-hoc study from the randomized controlled NORDIET trial.    In the first study, we identified a cross-sectional positive association between serum cathepsin S and two markers of cytokine-mediated inflammation, CRP and IL-6. These associations were similar in non-obese individuals. In longitudinal analyses, higher cathepsin S at baseline was associated with higher CRP and IL-6 levels after six years of follow-up. In the second study, we identified a cross-sectional association between increased serum levels of cathepsin S and reduced insulin sensitivity. These associations were similar in non-obese individuals. No significant association was observed between cathepsin S and insulin secretion. In longitudinal analysis, higher cathepsin S levels were associated with an increased risk of developing diabetes during the six-year follow-up. In the third study, we found that higher serum levels of cathepsin S were associated with increased mortality risk. Moreover, in the ULSAM cohort, serum cathepsin S was independently associated with cause-specific mortality from cardiovascular disease and cancer. In the fourth study, we identified that adherence to an ad libitum healthy Nordic diet for 6 weeks slightly decreased the levels of plasma cathepsin S in normal or marginally overweight individuals, relative to the control group. Changes in circulating cathepsin S concentrations were correlated with changes in body weight, LDL-C, and total cholesterol.    Conclusion: This thesis shows that circulating cathepsin S is a biomarker that independently reflects inflammation, insulin resistance, the risk of developing diabetes, and mortality risk. Furthermore, a Nordic diet moderately reduced cathepsin S levels in normal-weight and overweight men and women. This effect may be partially mediated by diet-induced weight loss and possibly by reduced LDL-C concentrations. 

Novel Statistical Methods in Quantitative Genetics : Modeling Genetic Variance for Quantitative Trait Loci Mapping and Genomic Evaluation

This thesis develops and evaluates statistical methods for different types of genetic analyses, including quantitative trait loci (QTL) analysis, genome-wide association study (GWAS), and genomic evaluation. The main contribution of the thesis is to provide novel insights in modeling genetic variance, especially via random effects models. In variance component QTL analysis, a full likelihood model accounting for uncertainty in the identity-by-descent (IBD) matrix was developed. It was found to be able to correctly adjust the bias in genetic variance component estimation and gain power in QTL mapping in terms of precision.  Double hierarchical generalized linear models, and a non-iterative simplified version, were implemented and applied to fit data of an entire genome. These whole genome models were shown to have good performance in both QTL mapping and genomic prediction. A re-analysis of a publicly available GWAS data set identified significant loci in Arabidopsis that control phenotypic variance instead of mean, which validated the idea of variance-controlling genes.  The works in the thesis are accompanied by R packages available online, including a general statistical tool for fitting random effects models (hglm), an efficient generalized ridge regression for high-dimensional data (bigRR), a double-layer mixed model for genomic data analysis (iQTL), a stochastic IBD matrix calculator (MCIBD), a computational interface for QTL mapping (qtl.outbred), and a GWAS analysis tool for mapping variance-controlling loci (vGWAS).

Optical Characterization and Optimization of Display Components : Some Applications to Liquid-Crystal-Based and Electrochromics-Based Devices

This dissertation is focused on theoretical and experimental studies of optical properties of materials and multilayer structures composing liquid crystal displays (LCDs) and electrochromic (EC) devices. By applying spectroscopic ellipsometry, we have determined the optical constants of thin films of electrochromic tungsten oxide (WOx) and nickel oxide (NiOy), the films’ thickness and roughness. These films, which were obtained at spattering conditions possess high transmittance that is important for achieving good visibility and high contrast in an EC device. Another application of the general spectroscopic ellipsometry relates to the study of a photo-alignment layer of a mixture of azo-dyes SD-1 and SDA-2. We have found the optical constants of this mixture before and after illuminating it by polarized UV light. The results obtained confirm the diffusion model to explain the formation of the photo-induced order in azo-dye films. We have developed new techniques for fast characterization of twisted nematic LC cells in transmissive and reflective modes. Our techniques are based on the characteristics functions that we have introduced for determination of parameters of non-uniform birefringent media. These characteristic functions are found by simple procedures and can be utilised for simultaneous determination of retardation, its wavelength dispersion, and twist angle, as well as for solving associated optimization problems. Cholesteric LCD that possesses some unique properties, such as bistability and good selective scattering, however, has a disadvantage – relatively high driving voltage (tens of volts). The way we propose to reduce the driving voltage consists of applying a stack of thin (~1µm) LC layers. We have studied the ability of a layer of a surface stabilized ferroelectric liquid crystal coupled with several retardation plates for birefringent color generation. We have demonstrated that in order to accomplish good color characteristics and high brightness of the display, one or two retardation plates are sufficient.

Utmaningen från andra berättelser : En studie om moraliskt omdöme, utvidgat tänkande och kritiskt reflekterande berättelser i dialogbaserad feministisk etik

The present study has a threefold aim: First, the theoretical aim is to give a contribution to refinement of the theory of dialogue based feminist ethics, concerning the understanding of judgment and narration within such an ethics.  The study also has an empirical aim, defined as to clarify what kind of knowledge, relevant to the moral judgment of an engaged outsider actor, can be received from dialogical interpretation and analysis of a limited selection of critically reflecting life stories. Third, a methodological aim is defined as to develop an approach to interpretation and analysis of reflecting life stories, which renders the storyteller visible as a reflecting moral subject, and makes the story accessible as a source of knowledge for the moral judgment of an engaged outsider actor. The thesis combines philosophical reflection and argumentation, with a narrative-hermeneutic method for interpretation of life stories, relating the two to each other in a hermeneutic process.  The theoretical reflection draws on Seyla Benhabibs theory of communicative ethics. A dialogue based model for moral justification and a likewise dialogue based model for political legitimacy are at the heart of this universalistic theory, although in combination with a conception of a narratively and hermeneutically constituted context sensitive moral judgment, based on Hannah Arendt’s concept “enlarged thought”. In the reflection, this model is related to other feminist theorizing within the tradition of dialogue based feminist ethics, as found in the works of Iris M. Young, Georgia Warnke and Shari Stone-Mediatore. The empirical study draws on three critically reflecting life stories from Israeli-Palestinian women activists for a just peace. The methodology for interpretation and analysis that is worked out combines dialogical interpretation as presented in Arthur W. Frank’s socio-narratology with a method for structural analysis derived from Shari Stone-Mediatores theory of storytelling as an expression of political resistance struggle. The results show that some stories drawing on marginalized experiences have a potential­ to stimulate further public debate through their capacity to enable a stereoscopic seeing, elucidating a tension between ideologically structured discourse and non-linguistic experience; implying that narrative-hermeneutic competence should be considered crucial for public debate.  

The kidney in different stages of the cardiovascular continuum

Patients with chronic kidney disease are at higher risk of developing cardiovascular disease. The complex, interaction between the kidney and the cardiovascular system is incompletely understood, particularly at the early stages of the cardiovascular continuum. The overall aim of this thesis was to clarify novel aspects of the interplay between the kidney and the cardiovascular system at different stages of the cardiovascular continuum; from risk factors such as insulin resistance, inflammation and oxidative stress, via sub-clinical cardiovascular damage such as endothelial dysfunction and left ventricular dysfunction, to overt cardiovascular death. This thesis is based on two community-based cohorts of elderly, Uppsala Longitudinal Study of Adult Men (ULSAM) and Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS). The first study, show that higher insulin sensitivity, measured with euglycemic-hyperinsulinemic clamp technique was associated to improve estimated glomerular filtration rate (eGFR) in participants with normal fasting plasma glucose, normal glucose tolerance and normal eGFR. In longitudinal analyses, higher insulin sensitivity at baseline was associated with lower risk of impaired renal function during follow-up. In the second study, eGFR was inversely associated with different inflammatory markers (C-reactive protein, interleukin-6, serum amyloid A) and positively associated with a marker of oxidative stress (urinary F2-isoprostanes). In line with this, the urinary albumin/creatinine ratio was positively associated with these inflammatory markers, and negatively associated with oxidative stress. In study three, higher eGFR was associated with better endothelial function as assessed by the invasive forearm model. Further, in study four, higher eGFR was significantly associated with higher left ventricular systolic function (ejection fraction). The 5th study of the thesis shows that higher urinary albumin excretion rate (UAER) and lower eGFR was independently associated with an increased risk for cardiovascular mortality. Analyses of global model fit, discrimination, calibration, and reclassification suggest that UAER and eGFR add relevant prognostic information beyond established cardiovascular risk factors in participants without prevalent cardiovascular disease. Conclusion: this thesis show that the interaction between the kidney and the cardiovascular system plays an important role in the development of cardiovascular disease and that this interplay begins at an early asymptomatic stage of the disease process.

The world of the Sumerian mother goddess : an interpretation of her myths

The present study is an interpretation of the two myths copied in the Old Babylonian period in which the Sumerian mother goddess is one of the main actors. The first myth is commonly called “Enki and Ninḫursaĝa”, and the second “Enki and Ninmaḫ”. The theoretical point of departure is that myths have society as their referents, i.e. they are “talking about” society, and that this is done in an ideological way. This study aims at investigating on the one hand which contexts in the Mesopotamian society each section of the myths refers to, and on the other hand which ideological aspects that the myths express in terms of power relations. The myths are contextualized in relation to their historical and social setting. If the myth for example deals with working men, male work in the area during the relevant period is discussed. The same method of contextualization is used regarding marriage, geographical points of reference and so on. Also constellations of mythical ideas are contextualized, through comparison with similar constellations in other Mesopotamian myths. Besides the method of contextualization, the power relations in the myths are investigated. According to this latter method, the categories at issue, their ranking, as well as their changed ranking, are noted. The topics of the myths are issues important for the kingship and the country, such as irrigation, trade, health and healing, birth, collective work, artisanry and rivalry. All these aspects are used in order to express what the power relations between the goddess Ninḫursaĝa/Ninmaḫ and the god Enki look like. The relations are negotiated and recalibrated, which leads to the goddess getting a lowered status. Part of the negotiations and recalibrations is gender behavior, which is related to historical developments in society. The present work points to the function of these myths as tools of recalibrating not only deities, but also men and women in society.

Microstructural, Mechanical and Tribological Characterisation of CVD and PVD Coatings for Metal Cutting Applications

The present thesis focuses on characterisation of microstructure and the resulting mechanical and tribological properties of CVD and PVD coatings used in metal cutting applications. These thin and hard coatings are designed to improve the tribological performance of cutting tools which in metal cutting operations may result in improved cutting performance, lower energy consumption, lower production costs and lower impact on the environment.  In order to increase the understanding of the tribological behaviour of the coating systems a number of friction and wear tests have been performed and evaluated by post-test microscopy and surface analysis. Much of the work has focused on coating cohesive and adhesive strength, surface fatigue resistance, abrasive wear resistance and friction and wear behaviour under sliding contact and metal cutting conditions. The results show that the CVD deposition of accurate crystallographic phases, e.g. α-Al2O3 rather than κ-Al2O3, textures and multilayer structures can increase the wear resistance of Al2O3. However, the characteristics of the interfaces, e.g. topography as well as interfacial porosity, have a strong impact on coating adhesion and consequently on the resulting properties.  Through the deposition of well designed bonding and template layer structures the above problems may be eliminated. Also, the presence of macro-particles in PVD coatings may have a significant impact on the interfacial adhesive strength, increasing the tendency to coating spalling and lowering the surface fatigue resistance, as well as increasing the friction in sliding contacts. Finally, the CVD-Al2O3 coating topography influences the contact conditions in sliding as well as in metal cutting. In summary, the work illuminates the importance of understanding the relationships between deposition process parameters, composition and microstructure, resulting properties and tribological performance of CVD and PVD coatings and how this knowledge can be used to develop the coating materials of tomorrow.

'Moving On' and Transitional Bridges : Studies on migration, violence and wellbeing in encounters with Somali-born women and the maternity health care in Sweden

During the latest decade Somali-born women with experiences of long-lasting war followed by migration have increasingly encountered Swedish maternity care, where antenatal care midwives are assigned to ask questions about exposure to violence. The overall aim in this thesis was to gain deeper understanding of Somali-born women’s wellbeing and needs during the parallel transitions of migration to Sweden and childbearing, focusing on maternity healthcare encounters and violence. Data were obtained from medical records (paper I), qualitative interviews with Somali-born women (II, III) and Swedish antenatal care midwives (IV). Descriptive statistics and thematic analysis were used. Compared to pregnancies of Swedish-born women, Somali-born women’s pregnancies demonstrated later booking and less visits to antenatal care, more maternal morbidity but less psychiatric treatment, less medical pain relief during delivery and more emergency caesarean sections and small-for-gestational-age infants (I). Political violence with broken societal structures before migration contributed to up-rootedness, limited healthcare and absent state-based support to women subjected to violence, which reinforced reliance on social networks, own endurance and faith in Somalia (II). After migration, sources of wellbeing were a pragmatic “moving-on” approach including faith and motherhood, combined with social coherence. Lawful rights for women were appreciated but could concurrently risk creating power tensions in partner relationships. Generally, the Somali-born women associated the midwife more with providing medical care than with overall wellbeing or concerns about violence, but new societal resources were parallel incorporated with known resources (III). Midwives strived for woman-centered approaches beyond ethnicity and culture in care encounters, with language, social gaps and divergent views on violence as potential barriers in violence inquiry. Somali-born women’s strength and contentment were highlighted, and ongoing violence seldom encountered according to the midwives experiences (IV). Pragmatism including “moving on” combined with support from family and social networks, indicate capability to cope with violence and migration-related stress. However, this must be balanced against potential unspoken needs at individual level in care encounters.With trustful relationships, optimized interaction and networking with local Somali communities and across professions, the antenatal midwife can have a “bridging-function” in balancing between dual societies and contribute to healthy transitions in the new society.

"Ungerska för rötternas skull" : Språkval och identitet bland andragenerationens ungrare i Sverige och Finland

This thesis is a comparative sociolinguistic study which describes and compares language choice among people with Hungarian background in Sweden and Finland and studies their views on the importance of the Hungarian language and Hungarian cultural heritage for identity. The future prospects of language maintenance and language shift and differences between the Swedish-Hungarians and the Finnish-Hungarians are discussed. A survey was completed among 50 Swedish-Hungarian informants and 38 Finnish-Hungarian informants during 2006. The survey was supplemented by in-depth interviews with 15 informants during 2007. The majority language, either Swedish or Finnish, is much more active in the second-generation Hungarians’ lives than Hungarian is. Hungarian is mostly used in the domain of family relations. The language choices made today are dependent on the informant’s situation during childhood, particularly the parents’ usage of the language and the ability to learn and use Hungarian, chiefly gained through contact with the parents’ mother country and other Hungarian speakers. For some informants, having Hungarian roots forms the sole foundation for belonging, while for others it is this heritage combined with the culture, the ability to use the language or specific character traits. The Hungarian background is most often seen as a treasure offering diversity in life. Finnish-Hungarians are generally more positive about their Hungarian background, have better competence in the language and a greater awareness of the culture than Swedish-Hungarians. The Hungarian language plays a central though often symbolic role. The most important conditions for minority language preservation are language competence together with the desire and opportunity to use it; whereof the largest deficit among second-generation Hungarians is knowledge of the Hungarian language. Only one-fourth of the informants have all of the conditions necessary to be able to maintain the language, which means that Hungarian is an endangered minority language in Sweden and Finland.