53 research outputs found
Using network centrality measures to manage landscape connectivity
We use a graph-theoretical landscape modeling approach to investigate how to identify central patches in the landscape as well as how these central patches influence (1) organism movement within the local neighborhood, and (2) the dispersal of organisms beyond the local neighborhood. Organism movements were theoretically estimated based on the spatial configuration of the habitat patches in the studied landscape. We find that centrality depends on the way the graph-theoretical model of habitat patches is constructed, although even the simplest network representation, not taking strength and directionality of potential organisms flows into account, still provides a coarse-grained assessment of the most important patches according to their contribution to landscape connectivity. Moreover, we identify (at least) two general classes of centrality. One accounts for the local flow of organisms in the neighborhood of a patch and the other for the ability to maintain connectivity beyond the scale of the local neighborhood. Finally, we study how habitat patches with high scores on different network centrality measures are distributed in a fragmented agricultural landscape in Madagascar. Results show that patches with high degree-, and betweenness centrality are widely spread, while patches with high subgraph- and closeness centrality are clumped together in dense clusters. This finding may enable multi-species analyses of single-species network models
Cross-Sector Review of Drivers and Available 3Rs Approaches for Acute Systemic Toxicity Testing
Acute systemic toxicity studies are carried out in many sectors in which synthetic chemicals are manufactured or used and are among the most criticized of all toxicology tests on both scientific and ethical grounds. A review of the drivers for acute toxicity testing within the pharmaceutical industry led to a paradigm shift whereby in vivo acute toxicity data are no longer routinely required in advance of human clinical trials. Based on this experience, the following review was undertaken to identify (1) regulatory and scientific drivers for acute toxicity testing in other industrial sectors, (2) activities aimed at replacing, reducing, or refining the use of animals, and (3) recommendations for future work in this area
Zinc Deficiency in Low and Middle Income Countries: Prevalence and Approaches for Mitigation
This review addresses the prevalence of zinc deficiency in Low and Middle Income Countries (LMICs) and assesses the available strategies for its alleviation. The paucity of national level data on the zinc deficiency in LMICs is partially due to the lack of a reliable biomarker. Zinc deficiency appears to be a public health problem in almost all the LMICs irrespective of the recommended indicators (plasma zinc concentration, dietary zinc adequacy and stunting prevalence) used. Based on plasma/serum zinc concentration (PZC), the most appropriate indicator at present, the prevalence of zinc deficiency in LMICs are of concern. Among the 25 countries for which national PZC data were available, 23 had a zinc deficiency prevalence of >20% for at least one physiological group. Zinc supplementation is largely restricted as an adjunct therapy for diarrhoea management in children, but the best platform and the most effective way of preventive zinc supplementation delivery needs to be determined. Impact assessment for current zinc fortification programmes in LMICs and the effectiveness of zinc supplementation as part of a multi-micronutrient powder is to be ascertained. Dietary diversification, though promising for LMICs, is in nascent stages of development at present. Inclusion of meat and animal products can be an important way to improve zinc status. Programmatic experience with the promotion of home processing techniques to increase absorbable zinc in the diet is lacking. Conventional biofortification techniques are gaining recognition in LMICs, however transgenic biofortification as a strategy remains controversial
Analysis of trends in mapping and assessment of ecosystem condition in Europe
Ecosystem condition is the overall quality of an ecosystem unit, in terms of its biological, physical and chemical characteristics underpinning its capacity to generate ecosystem services. Changes in ecosystem condition affect the delivery of services and therefore human well-being. Despite increasing research in this field, the relations between biodiversity, ecosystem condition and services are still not well understood. This study examined scientific articles and reports to analyse the development of ecosystem condition mapping and assessments in Europe since the year 2000. The aim was to provide an overview of the current state of research and to highlight some challenges for ecosystem condition and ecosystem services research. The review analysed the ecosystems under study, scales, methods, indicators, and the ecosystem services assessed. Based on this review, some gaps were identified, especially in the methods used for condition assessment, the coverage of ecosystems, and the applicability of indicators in policy. It is necessary to develop integrative methods to determine ecosystems condition and its influence on the ecosystem service provision, in order to produce robust information. The results of this review can be harnessed by people who need an overview about existing ecosystem condition studies, such as scientists, land managers or decision makers
Ravaged landscapes and climate vulnerability: The challenge in achieving food security and nutrition in post-conflict Timor-Leste
Food insecurity and malnutrition are prevalent in post-conflict countries. Climate change poses further challenges to their food production. Timor-Leste is an agrarian society that won independence in 2002 and is struggling to achieve food security and reduce undernutrition as the country modernizes. The economy depends on fossil fuel revenues and oil reserves are dwindling. A review of climate, agricultural, and nutrition data reveals high weather vulnerability, low agricultural productivity, and slow dietary and nutritional progress. But solutions exist. Agricultural sector actions can make important contributions to poverty reduction, food security, dietary diversity, micronutrient sufficiency, and overall nutrition. Agriculture can be made to be more nutrition- and gender-sensitive with a focus on mixed farming systems, biodiversity, climate-smart practices, and access to inputs, training, and technologies for farmers to enable sustainable and healthy rural livelihoods. Ultimately, productivity levels must improve to support the availability of sufficient and nutritious foods
Progress report / Aquaculture Genetics (Indonesia), phase III, year 1, Aug. 1989-Mar. 1990
Incorporates two reports relating to two different project number
Final report / Crop Animal System Research, Batumarta, Indonesia : phase II (1988/89-1990/91)
Final report / Carp Genetics (Dalhousie / Indonesia) phase II (1 July 1985-31 Mar. 1989)
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