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In this essay I discuss the ways in which not recognizing that the death of organisms plays a part in our food producing systems, distances us from life’s ecological processes and explore how this plays a role in devaluing the sources of our food. I argue that modern society’s deep separation from our agricultural systems play a part in our current ecological illiteracy.  相似文献   
84.
Botulism type E was first recognized as a major cause of fish mortality in the United States in 1979. This disease caused an estimated loss of 114 million juvenile salmon reared in earth-bottom ponds during the summer and fall of 1979 and 1980. The botulism outbreaks, preliminary laboratory results of experimental botulism, and precautions to be taken by fish farm employees are discussed.  相似文献   
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In the rain‐fed mixed‐farming systems of southern Australia, the consistent supply of high‐value forage is limited by a range of climatic, edaphic and systems constraints. Over 2 years, we compared biomass production and nutritional value of 30 accessions of perennial legumes, and predicted intake, grazing days and growth of ewes and lambs. There was significant variation in nutritional value and biomass production between and within species. Lucerne (Medicago sativa) and sulla (Hedysarum coronarium) produced the greatest amount of biomass and energy. There was variability among accessions in digestibility (DMD), acid detergent fibre (ADF) and crude protein, and the rate of change in these traits as plants matured. Trifolium species had the highest DMD across all growth stages. Hairy canary clover (Dorycnium hirsutum), erect canary clover (Dorycnium rectum), greater birdsfoot trefoil (Lotus uliginosus), Australian trefoil (Lotus australis) and running postman (Kennedia prostrata) had energy levels that would not maintain liveweight of mature sheep. In the second year, species differed in response to harvesting treatments. Lucerne and sainfoin (Onobrychis viciifolia) were more productive under a frequent cutting regime. Accessions of white clover (Trifolium repens), red clover (Trifolium pratense), alsike clover (Trifolium hybridum), cullen (Cullen australasicum), strawberry clover (Trifolium fragiferum), sainfoin and birdsfoot trefoil (Lotus corniculatus) showed some promise, while Tedera (Bituminaria bituminosa) and milkvetch (Astragalus cicer) performed poorly under the experimental conditions. We conclude by discussing additional agronomic and nutritional factors that need consideration when developing novel perennial legumes for mixed‐farming systems in the context of a changing climate.  相似文献   
87.
D Waxman  JR Peck 《Science (New York, N.Y.)》1998,279(5354):1210-1213
A mathematical model is presented in which a single mutation can affect multiple phenotypic characters, each of which is subject to stabilizing selection. A wide range of mutations is allowed, including ones that produce extremely small phenotypic changes. The analysis shows that, when three or more characters are affected by each mutation, a single optimal genetic sequence may become common. This result provides a hypothesis to explain the low levels of variation and low rates of substitution that are observed at some loci.  相似文献   
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To pursue a systematic approach to the discovery of functional connections among diseases, genetic perturbation, and drug action, we have created the first installment of a reference collection of gene-expression profiles from cultured human cells treated with bioactive small molecules, together with pattern-matching software to mine these data. We demonstrate that this "Connectivity Map" resource can be used to find connections among small molecules sharing a mechanism of action, chemicals and physiological processes, and diseases and drugs. These results indicate the feasibility of the approach and suggest the value of a large-scale community Connectivity Map project.  相似文献   
90.
The Tripartite collaboration (World Health Organization, the Food and Agriculture Organisation of the United Nations, and the World Organisation for Animal Health) produced two documents for consultation with Member Countries in 2017 ‐ Monitoring and Evaluation of the Global Action Plan on Antimicrobial Resistance: Proposed approach and the Global Framework for Development & Stewardship to Combat Antimicrobial Resistance: Draft Roadmap. These documents intend to support a strategic whole‐of‐system approach towards the World Health Organization's Global Action Plan on Antimicrobial Resistance. This paper outlines the recent thinking in antimicrobial stewardship being developed by the major international organisations involved with mitigating global antimicrobial resistance. The directions being set in key frameworks will need to be considered by Australian stakeholders as their own antimicrobial stewardship approaches and activities are formulated.  相似文献   
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