| 11. |
- Kuhlmann-Berenzon, S., et al.
(författare)
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Accounting for large-scale factors in the study of understory vegetation using a conditional logistic model
- 2007
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Ingår i: Environmental and Ecological Statistics. - : Springer Science and Business Media LLC. - 1352-8505 .- 1573-3009. ; 14:2, s. 149-159
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Tidskriftsartikel (refereegranskat)abstract
- Local-scale and large-scale factors can affect the presence of a species of understory vegetation in the forest. Local-scale factors may be the influence of surrounding trees, while climate and latitude are typically considered large-scale factors. A model for the presence of a species needs to take into account both scales. A conditional logistic model is proposed for those studies where only the local-scale factors are of interest and that avoids estimating the large-scale parameters. Conditioning is carried out by the number of quadrats in the plot where the vegetation is found. As the latter is a sufficient statistic for the large-scale factors, a model free from these parameters is obtained. Data gathered in the permanent sample plots of the 1985-1986 National Forest Inventory of Finland is used for illustration, where the local-scale factor of interest is the influence of the trees, quantified by an index based on the size and location of the trees. The model fitted to Vaccinium vitis-idaea showed a significant and positive influence of Scots pine on the presence of this species, while for Calamagrostis arundinacea, a decrease in the odds ratio was observed due to the influence of Norway spruce.
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| 15. |
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| 16. |
- Payne, L, et al.
(författare)
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'Did you have flu last week?' A telephone survey to estimate a point prevalence of influenza in the Swedish population
- 2005
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Ingår i: Euro surveillance : bulletin Europeen sur les maladies transmissibles = European communicable disease bulletin. - : European Centre for Disease Control and Prevention (ECDC). - 1560-7917. ; 10:12, s. 5-6
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Tidskriftsartikel (refereegranskat)abstract
- Sentinel surveillance usually underestimates the true burden of influenza in a population, as individuals must present to medical establishments to be included in the surveillance system. We carried out a telephone survey to estimate the national burden of influenza in the Swedish population for one week during the 2004/05 influenza season. Fixed-line telephone numbers were randomly sampled and households interviewed concerning influenza illness between 14-20 February 2005 (Week 7 of 2005). Questions regarding seasonal influenza vaccination status, symptoms and the impact of illness on daily life were also included. A self-defined influenza prevalence of 7.7% in week 7 of 2005 was estimated. On applying a case definition of ‘cough and fever and muscle pain’ for influenza like illness, the prevalence decreased to 3.6%. The survey provided insight into the burden of illness in the population further to that estimated through the sentinel surveillance system.
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| 17. |
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| 18. |
- Rehn, M., et al.
(författare)
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Unusual increase of psittacosis in southern Sweden linked to wild bird exposure, January to April 2013
- 2013
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Ingår i: Eurosurveillance. - 1025-496X .- 1560-7917. ; 18:19, s. 13-20
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Tidskriftsartikel (refereegranskat)abstract
- Free-living wild birds worldwide act as reservoir for Chlamydia psittaci, but the risk of transmission to humans through contact with wild birds has not been widely documented. From 12 January to April 9 2013, a total of 25 cases of psittacosis were detected in southern Sweden, about a threefold increase compared with the mean of the previous 10 years. A matched case-control study investigating both domestic and wild bird exposure showed that cases were more likely than controls to have cleaned wild bird feeders or been exposed to wild bird droppings in other ways (OR: 10.1; 95% CI: 2.1-47.9). We recommend precautionary measures such as wetting bird feeders before cleaning them, to reduce the risk of transmission of C. psittaci when in contact with bird droppings. Furthermore, C. psittaci should be considered for inclusion in laboratory diagnostic routines when analysing samples from patients with atypical pneumonia, since our findings suggest that psittacosis is underdiagnosed.
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