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Fenamidone is an imidazolinone fungicide recently introduced in viticulture practices. This work reports the validation and assessment of global uncertainty of a gas chromatographic with mass spectrometry method to analyze fenamidone in grapes and wines. This method consists in a simple and fast liquid-liquid extraction step followed by chromatographic determination. Limits of detection for fenamidone in grapes and wines were, respectively, 0.05 mg/kg and 0.06 mg/L, precision was below 9.4% and average recovery was 89 +/- 5%. In the concentration range from 0.05 to 1.00 mg/kg (or mg/L) of fenamidone, global uncertainty calculated following the EURACHEM/CITAC rules, and also by the Horwitz function, was below 25%. The EURACHEM/CITAC global uncertainty budget used gave lower estimates than those obtained from the Horwitz function.  相似文献   
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Direct inlet gas chromatography (GC) is becoming one of the most frequently used techniques for measurement of volatile organics in air. Although GC is an effective tool, its usefulness as a field method can be limited by retention times of several minutes or more, and by the limits of detection. In order to address these issues, a high speed GC system featuring a capillary cold trap inlet and variable speed electrometeramplifier was developed and tested.

The gas cooled inlet was used to collect and focus organic vapors from injection volumes of up to 1 ml. Resistance heating of the metal cold trap produced a narrow injection band that allowed simple separations to be completed in 5 to 20 seconds. Use of a variable speed electrometer-amplifier allowed the response time and noise suppression characteristics to be adjusted to the needs of the specific analysis.

Simple mixtures of organics including aromatics, alkanes and chlorinated hydrocarbons were separated in 20 seconds or less. The limits of detection for 13 test compounds ranged from less than 1 part per billion by volume (ppbv) to about 50 ppbv. Data presented here indicate that high speed GC using a cold trap inlet may be a feasible approach for near real-time measurement of volatile organics in ambient air.  相似文献   
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Atlantic herring, Clupea harengus, increase their swimming speed during low O2 (hypoxia) and it has been hypothesised that the behavioural response is modulated by the degree of “respiratory distress” (i.e. a rise in anaerobic metabolism and severe physiological stress). To test directly whether a deviation in physiological homeostasis is associated with any change in behavioural activity, we exposed C. harengus in a school to a progressive stepwise decline in water oxygen pressure and measured fish swimming speed and valid indicators of primary and secondary stress (i.e. blood cortisol, lactate, glucose and osmolality). Herring in hypoxia increased their swimming speed by 11–39% but only when was <8.5 kPa and in an unsteady (i.e. declining) state. In parallel with the shift in behaviour, plasma cortisol also exhibited an increase with plasma osmolality was subject to a transient rise at 8.5 kPa and plasma glucose was generally reduced at However, without any rise in anaerobically derived lactate levels, there was no evidence of respiratory distress at any set We show that a shift in physiological homeostasis is indeed linked with an increase in the swimming speed of herring but the physiological response reflects a hypoxia-induced shift in metabolic fuel-use rather than respiratory distress per se. The significance of this behavioural–physiological reaction is discussed in terms of behavioural-energetic trade-offs, schooling dynamics and the hypoxia tolerance of herring.  相似文献   
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Air pollution forecasting is not a new field but is certainly an area with only modest development since its early beginnings. Because ozone Is not a source emission but instead is formed from precursors, ozone episodes should be more readily forecasted than other pollutants by simply monitoring the precursors. The ozone empirical model developed within the course of this study is very site specific, therefore the major goal of the study was to establish the techniques which can be used to develop an ozone forecasting model for specific monitoring networks. The results of using the ozone forecasting model showed that even though errors as high as 25 % occurred the typical error In forecasting was in the 5-10% range.  相似文献   
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Often in land use evaluations, especially those in developing countries, only the financial aspect receives serious attention, while the social and ecological values are overlooked. This study compared the social and ecological values of four land use types (small-scale woodlot [SSW], boundary tree and shrub planting [BTP], homestead tree and shrub growing [HTG] and cereal farming [CF]) by a criteria-based scoring approach using a bao game. The impacts of local wealth status and proximity to a forest on the value the community renders to the land use types were also assessed. The value comparison, assessed by relative scoring, was accompanied by farmer’s explanations to reveal the existing local knowledge about land use values. It was found that HTG ≥ SSW > BTP > CF for both social and ecological values. Though this trend applies for the medium and rich households, the poor ones chose SSW as the most valuable. With increasing distance from a forest, the social and ecological values of land uses increased. The accompanying scoring justifications indicated the existence of in-depth ecological knowledge, which conform to contemporary scientific reports. Generally, this study showed that social and ecological values, besides financial values, strongly influence farmer’s decision in implementing various practices related to the land use types. Thus, such values are worth considering for a holistic understanding of the diverse benefits of land uses. Finally, the strong preference for tree and shrub-based land use types is a good opportunity for enhancing tree and shrub growing to minimize the major environmental problems (e.g., soil degradation, wood shortage and deforestation) in the central highlands of Ethiopia.  相似文献   
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Conservation projects subscribing to a community-based paradigm have predominated in the 21st century. We examined the context in which the phrase was coined and traced its growth over time. Community-based conservation first appeared in the literature in the early 1990s; but grew little until after the 5th World Parks Congress in 2003. Thereafter, publications describing community-based conservation approaches increased exponentially. The conference theme was Benefits Beyond Boundaries, and its goal was to provide an economic model based on revenue accrued from conservation fundraising and ecotourism to support ecosystems, wildlife, and people, particularly in the Global South. Such models tended not to incorporate, as a core principle, the heritage of local human communities. Human heritage varies substantially over time and space making generalization of conservation principles across scales challenging. Pitfalls that have grown out of the community-based conservation approaches in the Global South include fortress conservation, conservation militarism, consumptive and nonconsumptive ecotourism, and whiz-bang solutions. We propose 10 tenets in a human heritage-centered conservation framework (e.g., engage in conservation practices using local languages, thoughtfully propose and apply solutions consistent with human heritage, provide clear professional development pathways for individuals from local communities, and promote alternative revenue-generating programs centered in local communities, among others). Progressive philosophies can derive from authentic and ethical integration of local communities in conservation practice.  相似文献   
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