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排序方式: 共有263条查询结果,搜索用时 17 毫秒
71.
Roger Lee Mendoza 《Journal of medical economics》2018,21(4):313-317
We explore the behavioral methodology and “revolution” in economics through the lens of medical economics. We address two questions: (1) Are mainstream economic assumptions of utility-maximization realistic approximations of people’s actual behavior? (2) Do people maximize subjective expected utility, particularly in choosing from among the available options? In doing so, we illustrate–in terms of a hypothetical experimental sample of patients with dry eye diagnosis—why and how utility in pharmacoeconomic assessments might be valued differently by patients when subjective psychological, social, cognitive, and emotional factors are considered. While experimentally-observed or surveyed behavior yields stated (rather than revealed) preferences, behaviorism offers a robust toolset in understanding drug, medical device, and treatment-related decisions compared to the optimizing calculus assumed by mainstream economists. It might also do so more perilously than economists have previously understood, in light of the intractable uncertainties, information asymmetries, insulated third-party agents, entry barriers, and externalities that characterize healthcare. Behavioral work has been carried out in many sub-fields of economics. Only recently has it been extended to healthcare. This offers medical economists both the challenge and opportunity of balancing efficiency presumptions with relatively autonomous patient choices, notwithstanding their predictable, yet seemingly consistent, irrationality. Despite its comparative youth and limitations, the scientific contributions of behaviorism are secure and its future in medical economics appears to be promising. 相似文献
72.
目前,饮用水水源污染已成为全球范围的主要环境问题之一,而常规水处理工艺已经难以应对当前严重的水体微污染问题.通过对常规启动的固定化生物活性碳(IBAC)、非常规启动的固定化生物活性碳(IBAC新)和普通活性碳(GAC)对TOC、UV254、浊度、氨氮、亚硝酸盐氮等指标的处理效果的比较,得出IBAC无论在净化效果和运行稳定程度上都优于另两个碳柱. 相似文献
73.
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75.
当今的水处理技术中生物处理法已成为水污染控制的主要方法,尤其是现代生物技术将成为水污染控制领域重点开发和应用的技术手段。本文介绍了现代生物技术的内容与特点,着重综述了现代生物技术在废水生物处理、生物修复以及微生物水处理剂等方面的研究与应用状况,在此基础上提出今后现代生物技术在水污染控制领域中的研究方向。 相似文献
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77.
Enhancing ecosystem services in vineyards: using cover crops to decrease botrytis bunch rot severity
Botrytis bunch rot is a disease that causes loss of yield and quality in many fruit and vegetable crops in temperate climates worldwide. The rot is caused by the fungus Botrytis cinerea, a saprophytic necrotroph. In grapes, the presence of the fungus can reduce yield, taint wine and increase its sensitivity to oxidation. In the current work, inter-row phacelia and ryegrass were mulched in situ in winter 2005 and compared with a bare ground control. The mulches were applied under 10-year-old Chardonnay vines in a 10-replicate randomized block design in New Zealand. Functional soil biological activity increased by 1.5–4.5 times in the two cover crop treatments compared with the control, an effect related to elevated soil moisture in these treatments. This increase in soil moisture and a higher rate of soil biological activity increased vine debris degradation, reduced B. cinerea primary inoculum on the debris and decreased B. cinerea severity at flowering (December 2005) and harvest (April 2006). These results show the potential of mulched cover crops to enhance soil ecosystem services, reduce variable costs and improve the sustainability of viticulture and potentially other agricultural systems, in temperate climates worldwide. 相似文献
78.
Brian Cooke Peter Chudleigh Sarah Simpson Glen Saunders 《Australian economic history review》2013,53(1):91-107
Wild European rabbits are serious agricultural and environmental pests in Australia; myxoma virus and rabbit haemorrhagic disease virus have been used as biocontrol agents to reduce impacts. We review the literature on changes in rabbit numbers together with associated reports on the economic benefits from controlling rabbits on agricultural production. By using loss–expenditure frontier models in with and without biocontrol scenarios, it is conservatively estimated that biological control of rabbits produced a benefit of A$70 billion (2011 A$ terms) for agricultural industries over the last 60 years. The consequences for ongoing rabbit control and research investment are discussed. 相似文献
79.
Soil biota, ecosystem services and land productivity 总被引:6,自引:0,他引:6
Edmundo Barrios 《Ecological Economics》2007,64(2):269-285
The soil environment is likely the most complex biological community. Soil organisms are extremely diverse and contribute to a wide range of ecosystem services that are essential to the sustainable function of natural and managed ecosystems. The soil organism community can have direct and indirect impacts on land productivity. Direct impacts are those where specific organisms affect crop yield immediately. Indirect effects include those provided by soil organisms participating in carbon and nutrient cycles, soil structure modification and food web interactions that generate ecosystem services that ultimately affect productivity. Recognizing the great biological and functional diversity in the soil and the complexity of ecological interactions it becomes necessary to focus in this paper on soil biota that have a strong linkage to functions which underpin ‘soil based’ ecosystem services. Selected organisms from different functional groups (i.e. microsymbionts, decomposers, elemental transformers, soil ecosystem engineers, soil-borne pest and diseases, and microregulators) are used to illustrate the linkages of soil biota and ecosystem services essential to life on earth as well as with those associated with the provision of goods and the regulation of ecosystem processes. These services are not only essential to ecosystem function but also a critical resource for the sustainable management of agricultural ecosystems. Research opportunities and gaps related to methodological, experimental and conceptual approaches that may be helpful to address the challenge of linking soil biodiversity and function to the provision of ecosystem services and land productivity are discussed. These include: 1) integration of spatial variability research in soil ecology and a focus on ‘hot spots’ of biological activity, 2) using a selective functional group approach to study soil biota and function, 3) combining new and existing methodological approaches that link selected soil organisms, the temporal and spatial dynamics of their function, and their contribution to the provision of selected ‘soil based' ecosystem services, 4) using understanding about hierarchical relationships to manage soil biota and function in cropping systems, 5) using local knowledge about plants as indicators of soil quality, remote sensing and GIS technologies, and plant-soil biota interactions to help understand the impacts of soil biota at landscape scale, and 6) developing land quality monitoring systems that inform land users about their land's ecosystem service performance, improve capacities to predict and adapt to environmental changes, and support policy and decision-making. 相似文献
80.
机械加工行业含油废水的治理一直是困扰企业环保工作的难题,以济南柴油机股份有限公司中水处理站建设和运行为例,根据污水处理的现有条件,并针对生产工艺产生废水的具体特点,同时参考国内外污水生物处理工艺的发展情况,进行方案比较,选出采用"活性滤料生物滤池"的实施处理工艺这一最佳方案,有效杜绝了厂区所排的废水对环境的污染,实现了社会和企业的双赢. 相似文献