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- Olesen, Pernille J, et al.
(author)
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Reducing Global Warming and Adapting to Climate Change: The Potential of Organic Agriculture
- 2012
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Reports (other academic/artistic)abstract
- Climate change mitigation is urgent, and adaptation to climate change is crucial, particularly in agriculture, where food security is at stake. Agriculture, currently responsible for 20-30% of global greenhouse gas emissions (counting direct and indirect agricultural emissions), can however contribute to both climate change mitigation and adaptation. The main mitigation po-tential lies in the capacity of agricultural soils to sequester CO2 through building organic matter. This potential can be realized by employing sustainable agricultural practices, such as those com-monly found within organic farming systems. Examples of these practices are the use of organic fertilizers and crop rotations including legume leys and cover crops. Mitigation is also achieved in organic agriculture through the avoidance of open biomass burning, and the avoidance of synthetic fertilizers, the production of which causes emissions from fossil fuel use. Common organic practices also contribute to adaptation. Building soil organic matter increases water retention capacity, and creates more stabile, fertile soils, thus reducing vulnerability to drought, extreme precipitation events, floods and water logging. Adaptation is further supported by increased agro-ecosystem diversity of organic farms, based on management decisions, reduced ni-trogen inputs and the absence of chemical pesticides. The high diversity together with the lower input costs of organic agriculture is key to reducing production risks associated with extreme weather events. All these advantageous practices are not exclusive to organic agriculture. However, they are core parts of the organic production system, in contrast to most non-organic agriculture, where they play a minor role only. Mitigation in agriculture is however not restricted to the agricultural sector alone. Consumer pref-erences for products from conventional or organic farms, seasonal and local production, pest and disease resistant varieties, etc. strongly influence agricultural production systems, and thus the overall mitigation potential of agriculture. Even more influential are meat consumption and food wastage. Any discussion on mitigation of climate change in agriculture thus needs to address the entire food chain, and to be linked to general sustainable development strategies. The main challenges to dealing appropriately with the climate change mitigation and adaptation potential of organic agriculture, and agriculture in general, stem from a) insufficient understanding of some of the basic processes, such as the interaction of N2O emissions and soil carbon sequestra-tion, contributions of roots to soil carbon sequestration, and the life-cycle emissions of organic fer-tilizers, such as compost; b) lack of procedures for emissions accounting which adequately repre-sent agricultural production systems with multiple and diverse outputs, which also encompass eco-system services; c) the problem to identify and design adequate policy frameworks for supporting mitigation and adaptation in agriculture, i.e. such that do not put systemic approaches at a disad-vantage due to difficulties in the quantification of emissions, and in their allocation to single prod-ucts; d) the necessity to assure that the current focus on mitigation does not lead to neglect of other factors influencing the sustainability of agriculture, such as pesticide loads, eutrophication, acidifi-cation or soil erosion; and e) the open questions, how to address consumer behaviour and how to further changes in consumption patterns, in order to utilize their mitigation potential.
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2. |
- Johansson, Lena, 1972, et al.
(author)
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Midlife Psychological Distress Associated With Late-Life Brain Atrophy and White Matter Lesions: A 32-Year Population Study of Women.
- 2012
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In: Psychosomatic medicine. - 0033-3174. ; 74:2, s. 120-125
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Journal article (peer-reviewed)abstract
- Long-standing psychological distress increases the risk of dementia, especially Alzheimer's disease. The present study examines the relationship between midlife psychological distress and late-life brain atrophy and white matter lesions (WMLs), which are common findings on neuroimaging in elderly subjects. A population-based sample of 1462 women, aged 38 to 60 years, was examined in 1968, with subsequent examinations in 1974, 1980, 1992, and 2000. Computed tomography (CT) of the brain was done in 379 survivors in 2000, and of those, 344 had responded to a standardized question about psychological distress in 1968, 1974, and 1980. WMLs, cortical atrophy, and central atrophy (ventricular sizes) were measured at CT scans. Compared with women reporting no distress, those reporting frequent or constant distress at one examination or more (in 1968, 1974, and 1980) more often had moderate-to-severe WMLs (multiadjusted odds ratio = 2.39, 95% confidence interval = 1.16-4.92) and moderate-to-severe temporal lobe atrophy (multiadjusted odds ratio = 2.51, 95% confidence interval = 1.04-6.05) on brain CT in 2000. Frequent/constant distress was also associated with central brain atrophy, that is, higher bicaudate ratio, higher cella media ratio, and larger third-ventricle width. Long-standing psychological distress in midlife increases risks of cerebral atrophy and WMLs on CT in late life. More studies are needed to confirm these findings and to determine potential neurobiological mechanisms of these associations.
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3. |
- Skoog, Ingmar, 1954, et al.
(author)
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Head size may modify the impact of white matter lesions on dementia.
- 2012
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In: Neurobiology of aging. - : Elsevier BV. - 1558-1497 .- 0197-4580. ; 33:7, s. 1186-1193
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Journal article (peer-reviewed)abstract
- We aimed to examine whether total intracranial volume (TICV), a marker of premorbid brain size, modified the impact of the apolipoprotein E (apoE) e4 phenotype and ischemic white matter lesions (WMLs) on odds for dementia. The study comprised a population-based sample of 104 demented and 135 nondemented 85-year-olds, and included physical and neuropsychiatric examinations, and head computerized tomography (CT). Dementia disorders were defined according to standard criteria. TICV and WMLs were rated on computerized tomography. Using the highest group as reference, the risk for dementia, Alzheimer's disease (AD), and vascular dementia (VaD) was increased in those with the smallest half, tertile, and quartile of TICV. Smaller TICV increased the odds of dementia, Alzheimer's disease, and vascular dementia in participants with WMLs. WMLs were not associated with increased odds of dementia in those with the largest TICV. The interaction term WMLs*TICV was also significant. TICV did not modify the odds of dementia in those with the apolipoprotein e4 phenotype. Our results suggest that the impact of brain pathology on the risk of dementia is modified by premorbid brain size.
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