| 6451. |
- Toriola, Adetunji T, et al.
(författare)
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Serum 25-hydroxyvitamin D and the risk of ovarian cancer
- 2010
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Ingår i: European Journal of Cancer. - : Elsevier BV. - 0959-8049 .- 1879-0852. ; 46:2, s. 364-369
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: Ecological and experimental studies suggest that vitamin D may be associated with a reduced risk of ovarian cancer. In this study, we sought to determine the risk of developing ovarian cancer according to serum 25-hydroxyvitamin D (25-OHD) concentrations assessed on average 5 years before the diagnosis. METHODS: We conducted a population-based longitudinal case-control study nested within the Finnish Maternity Cohort (FMC) which contains serum samples of virtually all pregnant women in Finland since 1983. Among them, 201 ovarian cancers diagnosed within 10 years of serum sampling were randomly selected as cases for this study. For each case, we selected two controls matched for age, parity and sampling season (+/-4 weeks) and one control matched for age and parity but for the opposite sampling season (6 months+/-4 weeks). RESULTS: The relative risks (estimated as odds ratio, OR) for ovarian cancer comparing the lowest quintile to the highest quintile of serum 25-OHD concentration were 1.8 (95% CI 0.9-3.5) among controls matched for the same season, and 1.1 (95% CI 0.6-2.2) among controls matched for the opposite season. The OR among women with insufficient (<75nmol/L) serum 25-OHD concentration was 2.7 (95% CI 1.0-7.9, lower limit, 0.95) compared to that among those with sufficient (75nmol/L) serum 25-OHD concentration. No differences in the point estimates were observed between serous or mucinous histological subtypes of ovarian cancer. CONCLUSION: Overall, we did not observe a significant association between serum 25-OHD concentrations and the risk of ovarian cancer. However, we found evidence suggestive of an increased risk among women with low to insufficient serum 25-OHD concentrations.
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| 6452. |
- Torp, Mikaela, 1978-, et al.
(författare)
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Snow-induced changes in dwarf birch chemistry increase moth larval growth rate and level of herbivory
- 2010
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Ingår i: Polar Biology. - : Springer. - 0722-4060 .- 1432-2056. ; 33:5, s. 693-702
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Tidskriftsartikel (refereegranskat)abstract
- Changes in snow cover might influence arctic ecosystems to the same extent as increased temperatures. Although the duration of snow cover is generally expected to decrease in the future as a result of global warming, the amounts of snow might increase in arctic areas where much of the elevated precipitation will fall as snow. We examined the effects of an increased snow cover, as a result of a snow fence treatment, on soil nitrogen mineralization, plant phenology, plant chemistry (nitrogen and potential defense compounds), the level of invertebrate herbivory, and performance of invertebrate herbivores in an arctic ecosystem, using dwarf birch (Betula nana) and the autumnal moth (Epirrita autumnata) as study organisms. An enhanced and prolonged snow cover increased the level of herbivory on dwarf birch leaves. Larvae feeding on plants that had experienced enhanced snow cover grew faster and pupated earlier than larvae fed with plant material from control plots, indicating that plants from enhanced snow-lie plots produce higher-quality food to herbivores. The increased larval growth rate was strongly correlated with higher leaf nitrogen concentration in plants subjected to snow manipulation, and also to certain phenolic acids. Snow manipulation did not change net nitrogen mineralization rates in the soil or total carbon concentration in leaves, but it altered the within-season fluctuating pattern of leaf phenolic compounds. This study demonstrates a positive relationship between increased snow cover and level of herbivory on deciduous shrubs, thus proposing a negative feedback on the climate-induced dwarf shrub expansion in arctic areas.
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| 6453. |
- Torp, Mikaela, 1978-, et al.
(författare)
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The effect of snow on plant chemistry and invertebrate herbivory : Experimental manipulations along a natural snow gradient
- 2010
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Ingår i: Ecosystems (New York. Print). - : Springer. - 1432-9840 .- 1435-0629. ; 13:5, s. 741-751
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Tidskriftsartikel (refereegranskat)abstract
- Changing snow conditions have strong effects onnorthern ecosystems, but these effects are rarelyincorporated into ecosystem models and our perceptionof how the ecosystems will respond to awarmer climate. We investigated the relationshipsbetween snow cover, plant phenology, level ofinvertebrate herbivory and leaf chemical traits inBetula nana in four different habitats located along anatural snow cover gradient. To separate the effectof snow per se from other differences, we manipulatedthe snow cover with snow fences in threehabitats. The experimentally prolonged snow coverdelayed plant phenology, but not as much as expectedbased on the pattern along the natural gradient.The positive effect of the snow treatment onplant nitrogen concentration was also weaker thanexpected, because plant nitrogen concentrationclosely followed plant phenology. The level ofherbivory by leaf-chewing invertebrates increasedin response to an increased snow cover, at least atthe end of the growing season. The concentrationof phenolic substances varied among habitats,treatments and sampling occasions, indicating thatB. nana shrubs were able to retain a mosaic ofsecondary chemical quality despite altered snowconditions. This study shows that the effect of thesnow cover period on leaf nitrogen concentrationand level of herbivory can be predicted based ondifferences between habitats, whereas the effect ofa changed plant phenology on plant nitrogenconcentration is better explained by temporaltrends within habitats. These results have importantimplications for how northern ecosystemsshould respond to future climate changes.
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| 6454. |
- Torp, Mikaela, 1978-
(författare)
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The Effect of Snow on Plants and Their Interactions with Herbivores.
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The ongoing climate changes are predicted to accelerate fast in arctic regions with increases in both temperatures and precipitation. Although the duration of snow cover is generally expected to decrease in the future, snow depth may paradoxically increase in those areas where a large amount of the elevated precipitation will fall as snow. The annual distribution and duration of snow are important features in arctic ecosystems, influencing plant traits and species interactions in various ways. In this thesis, I investigated the effect of snow on plants and their interactions with herbivores by experimentally increasing the snow cover by snow fences in three different habitats along an environmental gradient in Abisko, northern Sweden. I found that the snow cover mattered for plant quality as food for herbivores and herbivore performance. An enhanced and prolonged snow cover increased the level of insect herbivory on dwarf birch leaves under field conditions. Autumnal moth larvae feeding on leaves that had experienced increased snow-lie grew faster and pupated earlier than larvae fed with leaves from control plots. These findings indicated that plants from snow-rich plots produced higher-quality food for herbivores. My studies showed that differences in snow-lie explained parts of the within-year spatial and seasonal variation in plant chemistry and patterns of herbivory in this arctic landscape. The relationship between leaf nitrogen concentration and plant phenology was consistent between treatments and habitats, indicating that snow per se, via a delayed phenology, was controlling the nitrogen concentration. The relationship between leaf age and level of herbivory was positive in the beginning of the growing season, but negative in the end of the growing season, indicating an increasing importance of plant palatability and a decreasing importance of exposure time in determining the level of herbivory throughout the growing season. The concentrations of phenolics varied among habitats, treatments and sampling occasions, suggesting that these plants were able to retain a mosaic of secondary chemical quality despite altered snow conditions. Furthermore, the nutrient limiting plant growth, according to N:P ratio thresholds, appeared to shift from nitrogen to phosphorus along the topographic gradient from snow-poor ridges to more snow-rich heathlands and fens. Snow addition had, however, no significant effect on other nutrient concentrations than nitrogen and no significant effect on the leaf N:P ratio, indicating that differences in snow cover could not explain the variation in plant nutrient concentrations among habitats. In a five-year study, I found opposing inter-annual effects of increased snow on plant chemistry. In contrast to earlier results, the effect of snow-lie on plant nitrogen concentration was predominantly negative. However, the effect of increased snow cover on the level of herbivory remained predominantly positive. The strong within-year relationship between snow-melt date (via plant phenology) and plant nitrogen concentration and level of herbivory could not predict inter-annual variation in the effect of snow manipulation. I did not find any conclusive evidence for a single factor causing the inter-annual opposing effect of snow addition, but the results indicated that interactions with summer and winter temperatures might be important. In conclusion, this thesis showed that climate-induced changes in snow conditions will have strong effects on plant traits and plant-herbivore interactions. However, alterations in snow cover do not influence all plant traits and the effect may vary in time and space.
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| 6455. |
- Torstensson, Niklas
(författare)
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Judging the Immigrant : Accents and Attitudes
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Spoken language as a means of communication contains huge amounts of information apart from the linguistic message that is conveyed. It is often the first channel of interaction between people and based on the speaker’s manner of talk, we create a mental image of the speaker as a person, of the speaker’s background, origin and personal qualities. Through five case studies, this dissertation investigates how immigrants to Sweden are judged based on their foreign accents (Cases 1—3) and how the use of an interpreter in court can affect the legal process and the judging of the immigrant (Cases 4—5). Case 1 investigated Swedish students’ attitudes towards immigration and immigrants through a survey-based study and revealed that Swedish students hold predominantly positive attitudes towards immigrations and immigrants. Case 2, using accent imitation, asked if Swedish speakers have a cognitive prototype for British English accented Swedish and found that this was the case. This demonstrated that Swedes have models of accented Swedish accents. Case 3 asked Swedish students to rate their impressions of speakers of nine foreign accented Swedish voices on 18 six-point semantic differential scales. They also rated their impressions of each voice for five social factors. The results suggest that the listeners evaluated the voices based on perceived social desirability, or perceived cultural distance between the listener and the voice’s country of origin. Juxtaposing these findings with those of Case 1 suggests that even among a group who are positive to immigrants and immigration some groups of immigrants are more welcome than others. Case 4 examined discourse disfluencies in a bilingual court hearing and a Swedish-Polish bilingual court hearing in detail. The case showed that most of the dialogue-related difficulties have other sources than the interpreter, even if the interpreter at first glance often appeared to be part of the problem rather than part of the solution. Case 5 examined the interpreter’s role in courtroom dialogue situations through interviews with a court interpreter and a lay judge. The study found that the picture of the interpreter’s role differs between the various actors in the court setting. This, in combination with a lack of knowledge about cultural differences in dialogue strategies, creates complications, can have an impact on the perception of the witness and, ultimately, affect the legal rights of the accused. Furthermore, as the interpreter most frequently speaks foreign accented Swedish, the perception and evaluation of their foreign accented Swedish can further place some immigrant groups at a double legal disadvantage when being judged.
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| 6456. |
- Torstensson, Niklas, et al.
(författare)
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The Court Interpreter : Creating an interpretation of the facts
- 2011
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Ingår i: International Journal of Law, Language & Discourse. - Daw Park 5041 South Australia : Asian EFL Group. - 1839-8308. ; 1:3, s. 59-83
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Tidskriftsartikel (refereegranskat)abstract
- A fair trail is impossible without an interpreter when anyone taking part in the court proceedings does not know the national language, yet the use of an interpreter affects the judging of an immigrant and perhaps their right to a trial as fair as the one offered to a native speaker of the national language. At times courtroom conversation using an interpreter gets confusing, interrupted, and breaks down. These disfluencies can be the result of a lack of linguistic and cultural insight by any of the parties. This paper focuses on how interpreters and legal staff perceive the court interpreter’s role, and the creation of the interpretation. Using qualitative semi-structured interviews, it became clear that the interpreter and the lay judge hold different views. The interviews also revealed a degree of mutual mistrust.. Yet, in spite of this, a feeling that the bilingual communication in the courts works reasonably well most of the time also came through in the interviews and that with better education for all parties the courtroom could become a fairer legal context.
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| 6457. |
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| 6458. |
- Toscano, G., et al.
(författare)
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Plasmonic nanostructures : Local versus nonlocal response
- 2010
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Ingår i: Plasmonics. - : SPIE - International Society for Optical Engineering. - 9780819482532 ; , s. 77571T-
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Konferensbidrag (refereegranskat)abstract
- We study the importance of taking the nonlocal optical response of metals into account for accurate determination of optical properties of nanoplasmonic structures. Here we focus on the computational physics aspects of this problem, and in particular we report on the nonlocal-response package that we wrote for state-of the art numerical software, enabling us to take into account the nonlocal material response of metals for any arbitrarily shaped nanoplasmonic structures, without much numerical overhead as compared to the standard local response. Our method is a frequency-domain method, and hence it is sensitive to possible narrow resonances that may arise due to strong electronic quantum confinement in the metal. This feature allows us to accurately determine which geometries are strongly affected by nonlocal response, for example regarding applications based on electric field enhancement properties for which metal nanostructures are widely used.
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| 6459. |
- Toss, Fredrik, 1984-, et al.
(författare)
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Abdominal and gynoid adiposity and the risk of stroke
- 2011
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Ingår i: International Journal of Obesity. - : Springer Science and Business Media LLC. - 1476-5497 .- 0307-0565. ; 35:11, s. 1427-1432
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Tidskriftsartikel (refereegranskat)abstract
- Background: Previous studies have indicated that fat distribution is important in the development of cardiovascular disease (CVD). We investigated the association between fat distribution, as measured by dual energy X-ray absorptiometry (DXA), and the incidence of stroke. Methods: A cohort of 2751 men and women aged >= 40 years was recruited. Baseline levels of abdominal, gynoid and total body fat were measured by DXA. Body mass index (BMI, kg m(-2)) was calculated. Stroke incidence was recorded using the regional stroke registry until subjects reached 75 years of age. Results: During a mean follow-up time of 8 years and 9 months, 91 strokes occurred. Of the adiposity indices accessed abdominal fat mass was the best predictor of stroke in women (hazard ratio (HR) = 1.66, 95% confidence interval (CI) = 1.23-2.24 per standard deviation increase), whereas the ratio of gynoid fat to total fat mass was associated with a decreased risk of stroke (HR = 0.72, 95% CI = 0.54-0.96). Abdominal fat mass was the only of the adiposity indices assessed that was found to be a significant predictor of stroke in men (HR = 1.49, 95% CI = 1.06-2.09). The associations between abdominal fat mass and stroke remained significant in both women and men after adjustment for BMI (HR = 1.80, 95% CI = 1.06-3.07; HR = 1.71, 95% CI = 1.13-2.59, respectively). However, in a subgroup analyses abdominal fat was not a significant predictor after further adjustment for diabetes, smoking and hypertension. Conclusion: Abdominal fat mass is a risk factor for stroke independent of BMI, but not independent of diabetes, smoking and hypertension. This indicates that the excess in stroke risk associated with abdominal fat mass is at least partially mediated through traditional stroke risk factors. International Journal of Obesity (2011) 35, 1427-1432; doi: 10.1038/ijo.2011.9; published online 22 February 2011
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| 6460. |
- Toss, Fredrik, 1984-
(författare)
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Body fat distribution, inflammation and cardiovascular disease
- 2011
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Cardiovascular disease (CVD) is one of the major health issues of our time. The prevalence of CVD is increasing, both in industrialized and in developing countries, and causes suffering and a decreased quality of life for millions of people worldwide. CVD can have multiple etiologies, but the main underlying cause is atherosclerosis, which causes blood clot formation and obstructs vital arteries. Multiple risk factors of atherosclerosis have been identified, and body fatness is one of the most important ones. The main aims of this thesis were to investigate the relation between body fatness and: CVD risk factors (paper I), incident stroke (paper II), and overall mortality (paper III). The results showed that abdominal obesity is strongly associated with both CVD risk factors and stroke incidence (papers I-II). The results also suggested that a substantial part of the association between increased body fat and stroke can be explained by an increase in traditional stroke risk factors associated with increased body fat (paper II). A gynoid fat distribution, with a high share of fat located around the hip, is, on the other hand, associated with lower risk factor levels in both men and women, and with a decreased risk of stroke in women (papers I-II). This illustrates the importance of assessing the overall distribution of body fat rather, than solely focusing on total body fatness. In elderly women, total body fat was found to be associated with increased survival, while abdominal fat moderately increased mortality risk (paper III). Lean mass (fat-free mass) was strongly associated with increased survival among elderly men and women (paper III). Erythrocyte sedimentation rate (ESR) is an indicator of inflammation and, possibly, an indicator of atherosclerotic disease. In paper IV, the relationship between ESR in young adulthood and the later risk of myocardial infarction (MI) was studied. Results showed that higher levels of ESR were associated with a higher MI risk, in a dose-responsive manner, and was independent of other well-established risk factors. In summary, both total and regional fat distribution are associated with CVD risk factors and stroke, but do not seem to correspond to an increase in mortality risk among the elderly. Also, inflammation, detected as an increase in ESR, is associated with long term MI risk in young men.
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