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This paper investigates the impact of Fairtrade and organic certification on household income of smallholder coffee farmers in the Jinotega Municipality of Nicaragua. Using a sample of 233 coffee farming households and employing endogenous switching regression model and propensity score matching method, the results found that Fairtrade and organic certification standards have different effects on the certified farmers; while Fairtrade farmers had experienced yield gains, organic farmers had the price advantage. However, the overall impact of these certification standards on the total household income is found to be statistically not significant. While some of the Fairtrade-certified cooperatives have used the social premium in creating community-level infrastructure, there is a need for more investment. The major constraint the organic-certified farmers face is lack of availability of adequate organic inputs such as manures and organic herbicides.  相似文献   
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The chemical composition as well as the water uptake characteristics of aerosols was determined in size-segregated samples collected during November 2002 on the Slovenian coast. Major ions, water-soluble organic compounds (WSOC), short-chain carboxylic acids and trace elements were determined in the water-soluble fraction of the aerosol. Total aerosol black carbon (BC) was measured from filter samples. Our results showed that the origin of air masses is an important factor that controls the variation in the size distribution of the main components. Very high concentrations of WSOC as well as higher concentrations of BC were found under mostly continental influence. Besides the main ionic species (SO4(2-), NH4(+), K+) in the finest size fraction (0.17-0.53 microm), the concentration of NO3(-) was also high. The difference between the two different air mass origins is particularly expressed for Cl-, Na+, Mg2+ and Ca2+ determined in particles larger than 1.6 microm. As expected, a very good correlation was found between Na+ and Cl-. A good correlation was found between sea salt elements and elements of crustal origin (Na+, Cl-, Mg2+, Ca2+, Sr). A good relationship between typical anthropogenic tracers (K, V and Pb) was also observed. The mass growth factors, for all size fractions of aerosols collected under continental influence were very low (maximum 2.23 at 94%, 1.6-5.1 microm), while under marine influence the mass growth factors increased significantly with the particle size. At 97% humidity, the mass growth factors were 6.95 for the size fraction 0.53-1.6 microm and 9.78 for larger particles (1.6-5.1 microm).  相似文献   
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The realisation of an opto-chemical ammonia sensor suitable for personal monitoring tasks is described, comprising a cyanine dye immobilised in a microporous glass thin film. The fabrication of sensor platforms incorporating embossed grating couplers provides a compact optical design with effective waveguiding characteristics, resulting in reversible ammonia sensitivity in the 5-100 ppm range in under 2 min. Cross-sensitivity of sensor response with water and other potential interferents is considered.  相似文献   
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ABSTRACT

In the context of food policy, sustainability functions as a normative principle but also constitutes a highly contested arena. The study presented in this paper establishes how discursive dynamics amongst professionals involved in matters of food distribution, retail, consumption and waste lead to food policy themes being framed as issues of sustainability. Analysing varied UK-based data (trade magazine articles, policy documents and interviews with retail, non-profit and consultancy representatives), three interpretative frames of sustainability are identified: consumer sovereignty, economic rationality and stewardship. Focusing on three themes of food sustainability – organic consumption, protein diversity and waste reduction – it is shown how these interpretative frames constitute the discursive framework relevant to food policy. Based on these findings, it is shown how in the analysed debates environmental concerns are sidelined.  相似文献   
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Abstract

Energy management in small to medium enterprises (SMEs) remains undeveloped due to competing priorities and a lack of specialist knowledge. However considerable savings can be demonstrated where companies take the time to investigate their energy use. Savings of over 20% can be achieved through changes to operational and behavioural practice. Additional benefits, such as improved production tracking and improved maintenance, can been seen which add to the value in undertaking an energy monitoring and targeting (M&T) plan. The method described involves the application of a series of ‘virtuous’ cycles of engagement and energy savings that can be applied from the highest factory level right down to a specific machine. The analysis of overall energy use from utility bills and the visualisation of typical machine power profiles aid in understanding the drivers of energy consumption and in engaging management in energy efficiency. The monitoring of specific machines in production highlights the significant consumption of electricity during non-productive times. The development of energy performance indicators is described for product variations which can be useful in tendering for business and selecting optimum production pathways. The approach is illustrated with data from a case study of a precision engineering SME based in Limerick, Ireland.  相似文献   
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