| 1. |
- Stocks, Tanja, 1977-
(författare)
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Metabolic factors and cancer risk : prospective studies on prostate cancer, colorectal cancer, and cancer overall
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: A large number of prospective studies have shown that overweight and diabetes are related to an increased risk of many cancers, including colorectal cancer. In contrast, diabetes has been related to a decreased risk of prostate cancer, and overweight has been related to an increased risk of fatal, but not of incident, prostate cancer. Data from studies on metabolic factors related to overweight and diabetes, and the association with cancer risk, are limited. Aim: The aim of this thesis was to study metabolic factors in relation to risk of prostate cancer (paper I and III), colorectal cancer (paper II and V), and cancer overall (paper VI). Methods: Study designs were i) case-control studies, nested within the Northern Sweden Health and Disease Cohort (paper I and II), and ii) cohort studies of the Swedish Construction Workers cohort (paper III), and the Metabolic syndrome and Cancer project (Me-Can) comprising seven European cohorts (paper V and VI). Paper IV was a descriptive paper of Me-Can. Results, prostate cancer: In paper I, increasing levels of several factors related to insulin resistance (insulin, insulin resistance index, leptin, HbA1c, and glucose) were associated with a decreased risk of overall incident prostate cancer, and the associations were stronger for non-aggressive tumours. In paper III, increasing levels of blood pressure was associated with a significant decreased risk of overall incident prostate cancer and of non-aggressive tumours. Body mass index (BMI) was significantly positively related to fatal prostate cancer. Results, colorectal cancer: In paper II, obesity, hypertension, and hyperglycaemia, were associated with an increased risk of colorectal cancer, and presence of two or three of these factors was associated with a higher risk than the presence of one single factor. In paper V, BMI was associated with a significant linear positive association with risk of colorectal cancer in men and women, and significant positive associations were also found in men for blood pressure and triglycerides. A high metabolic syndrome score, based on levels of BMI, blood pressure, glucose, cholesterol, and triglycerides, was associated with a significant increased risk of colorectal cancer in men and women. The association was stronger than for any of the factors in single, but there was no evidence of a positive interaction between these metabolic factors. Results, cancer overall: Blood glucose was significantly positively associated with risk of incident and fatal cancer overall, and at several specific sites. The associations were stronger in women than in men, and for fatal than for incident cancer. Conclusions: Results from these studies indicate that elevated blood glucose is related to an increased risk of cancer overall and at several specific sites, and further, that overweight and metabolic aberrations increase the risk of colorectal cancer in an additive way. The association with prostate cancer seems to be more complex; insulin resistance and high blood pressure were in our studies related to a decreased risk of overall incident prostate cancer and of non-aggressive tumours, whereas overweight increased the risk of fatal prostate cancer.
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| 2. |
- Carlsson, Per, 1959-
(författare)
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Algorithms for Electronic Power Markets
- 2004
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In this thesis we focus resource allocation problems and electronic markets in particular. The main application area of ours is electricity markets. We present a number of algorithms and include practical experience. There is an ongoing restructuring of power markets in Europe and elsewhere, this implies that an industry that previously has been viewed as a natural monopoly becomes exposed to competition. In the thesis we move a step further suggesting that end users should take active part in the trade on power markets such as (i) day-ahead markets and (ii) markets handling close to real-time balancing of power grids. Our ideas and results can be utilised (a) to increase the efficiency of these markets and (b) to handle strained situations when power systems operate at their limits. For this we utilise information and communication technology available today and develop electronic market mechanisms designed for large numbers of participants typically distributed over a power grid. The papers of the thesis cover resource allocation with separable objective functions, a market mechanism that accepts actors with discontinuous demand, and mechanisms that allow actors to express combinatorial dependencies between traded commodities on multi-commodity markets. Further we present results from field tests and simulations.
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| 3. |
- Magnusson Sporre, Cecilia, 1968-
(författare)
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Måltidsgörarens utmaningar : komplexiteten i det medvetna måltidsgörandet
- 2015
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- I denna avhandling synliggörs måltidsgörarna, en omfångsrik grupp med skilda kompetenser och yrkesprofessioner. Det gemensamma är att alla är delaktiga i måltidsgörandet genom planering, tillagning och service av måltider serverade i olika verksamheter. Avhandlingen är kvalitativ, ett empiriskt-holistiskt perspektiv, med relevans både inom och utom akademin, en så kallad frågedriven tvärvetenskap.Avhandlingens övergripande syfte är att synliggöra måltidsgörandet och den komplexitet som utmärker måltidsgörarens profession och uppgift. Detta besvaras genom fyra artiklar, uppdelat i delstudie 1: FAMM och delstudie 2: Den medvetna måltiden. Metoder som använts i studien är, forskningscirklar, dokumentstudier, intervjuer och kvalitativ innehållsanalys. Avhandlingen belyser tre perspektiv: Ett samhälleligt perspektiv, där människors mat- och måltidsvanor relateras till samhällsutvecklingen. måltidsperspektivet som är kärnan i hela avhandlingen samt kunskapsperspektivetsom har betydelse för den gastronomiska utbildningen.Avhandlingens bidrag är att belysa: hur FAMM har vandrat från den akademiska gastronomikontexten till statliga myndigheter och vidare till måltidsgörarnas olika yrkesprofessioner i de offentliga storköken i kommuner och landsting; måltidsgörarnas komplexa och meningsskapande professioner och utmaningar i arbetet med måltidsgörandet; Den nya medvetna måltidens komplexitet med ett måltidsgörande där alla stadier genomsyras av etisk reflektion (att veta hur), från jord till bord; behovet av universitetsutbildning med gastronomiskt perspektiv samt kompetensutveckling för offentlig sektors måltidsgörare.Den gastronomiska diskursen som framträder i den offentliga måltidssektorn pekar åt samma håll som den så kallade gastronomiska revolutionen inom restaurangnäringen. Resultaten öppnar för intressanta fortsatta studier av det politiska matklimatets betydelse för måltidsgörarna och måltidsgörandet.
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| 4. |
- Wirén, Sara, 1981-
(författare)
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Prospective studies of hormonal and life-style related factors and risk of cancer
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: Androgens are important in prostate cancer development but how circulating levels of androgens affect risk of prostate cancer of different aggressiveness is not clear. Being childless has been associated with a lower risk of prostate cancer, but it is not clear if this association is causal or a result of residual confounding. Fathering of dizygotic twins, a marker of high fertility, has not been studied in relation to risk of prostate cancer.Another marker of life-long hormonal exposure is height, which has been associated with increased risk of cancer and cancer death. However, the association to separate cancer sites has not been consistent.The aims of this thesis were to study hormonal factors (paper I), and proxies of hormonal factors (paper II and III), and risk of prostate cancer; as well as height and risk of cancer and cancer death by separate sites (paper IV).Methods: Study designs were i) case-control studies, nested within the Västerbotten Intervention Project (paper I), and in Prostate Cancer database Sweden 2.0 (PCBaSe 2.0) (paper II and III), and ii) cohort study, in the Metabolic Syndrome and Cancer project (Me-Can) (paper IV).Results, prostate cancer: In paper I, increasing levels of serum androgens were not associated with risk of prostate cancer overall or in tumor risk categories. In paper II, childless men had a lower risk of prostate cancer, overall and in all risk categories, compared to fathers, an association which was in part explained by differences in marital status and educational level. In paper III, fathers of dizygotic twins did not have an increased risk of prostate cancer, either overall or in risk categories, when compared to fathers of singletons.Results, cancer overall: In paper IV, height was associated with an increased risk of cancer and cancer death overall in both women and men. The strongest association for cancer was to malignant melanoma in both women and men, and for cancer death to post-menopausal breast cancer in women and renal cell carcinoma in men.Conclusions: These studies indicate that hormonal factors, when studied as serum levels or when studied using proxies of fertility, do not have a major impact on the risk of prostate cancer. The association between height and an increased risk of cancer appears robust for total cancer and cancer death, as well as for several separate cancer sites.
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