| 1. |
- Power, M. J., et al.
(författare)
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Changes in fire regimes since the Last Glacial Maximum : an assessment based on a global synthesis and analysis of charcoal data
- 2008
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Ingår i: Climate Dynamics. - : Springer Science and Business Media LLC. - 0930-7575 .- 1432-0894. ; 30:7-8, s. 887-907
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Tidskriftsartikel (refereegranskat)abstract
- Fire activity has varied globally and continuously since the last glacial maximum (LGM) in response to long-term changes in global climate and shorter-term regional changes in climate, vegetation, and human land use. We have synthesized sedimentary charcoal records of biomass burning since the LGM and present global maps showing changes in fire activity for time slices during the past 21,000 years (as differences in charcoal accumulation values compared to pre-industrial). There is strong broad-scale coherence in fire activity after the LGM, but spatial heterogeneity in the signals increases thereafter. In North America, Europe and southern South America, charcoal records indicate less-than-present fire activity during the deglacial period, from 21,000 to ∼11,000 cal yr BP. In contrast, the tropical latitudes of South America and Africa show greater-than-present fire activity from ∼19,000 to ∼17,000 cal yr BP and most sites from Indochina and Australia show greater-than-present fire activity from 16,000 to ∼13,000 cal yr BP. Many sites indicate greater-than-present or near-present activity during the Holocene with the exception of eastern North America and eastern Asia from 8,000 to ∼3,000 cal yr BP, Indonesia and Australia from 11,000 to 4,000 cal yr BP, and southern South America from 6,000 to 3,000 cal yr BP where fire activity was less than present. Regional coherence in the patterns of change in fire activity was evident throughout the post-glacial period. These complex patterns can largely be explained in terms of large-scale climate controls modulated by local changes in vegetation and fuel load.
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| 3. |
- Wahl, Hans-Werner, et al.
(författare)
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The Home Environment and Disability-Related Outcomes in Aging Individuals: What Is the Empirical Evidence?
- 2009
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Ingår i: The Gerontologist. - : Oxford University Press (OUP). - 1758-5341 .- 0016-9013. ; 49:3, s. 355-367
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: Building on the disablement process model and the concept of person-environment fit (p-e fit), this review article examines 2 critical questions concerning the role of home environments: (a) What is the recent evidence supporting a relationship between home environments and disability-related outcomes? and (b) What is the recent evidence regarding the effects of home modifications on disability-related outcomes? Design and Methods: Using computerized and manual search, we identified relevant peer-reviewed original publications and review articles published between January 1, 1997, and August 31, 2006. For Research Question 1, 25 original investigations and for Research Question 2, 29 original investigations and 10 review articles were identified. Results: For Research Question 1, evidence for a relationship between home environments and disability-related outcomes for older adults exists but is limited by cross-sectional designs and poor research quality. For Research Question 2, evidence based on randomized controlled trials shows that improving home environments enhances functional ability outcomes but not so much falls-related outcomes. Some evidence also exists that studies using a p-e fit perspective result in more supportive findings than studies that do not use this framework. Implications: Considerable evidence exists that supports the role of home environments in the disablement process, but there are also inconsistencies in findings across studies. Future research should optimize psychometric properties of home environment assessment tools and explore the role of both objective characteristics and perceived attributions of home environments to understand person-environment dynamics and their impact on disability-related outcomes in old age.
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