超高效液相色谱/三重四极杆质谱联用(ACQUITY UPLC/Xevo TQ-S)检测蜂花粉中吡虫啉残留量

正在分析复杂环境样品中的痕量污染物时,通常会受到基质的严重干扰,使得在进行亚ng·g-1浓度水平检测时,所用仪器面临着必须满足灵敏度要求的挑战.杀虫剂暴露会对蜂群产生致死和亚致死效应,若要监控这些效应带来的影响则需要对蜜蜂和蜂产品中的杀虫剂水平进行可靠定量.某地区使用吡虫啉杀虫剂来应对昆虫的侵害,我们对该地区的蜜蜂样本及花粉产品进行了吡虫啉残留分析,花粉中平均含有20%蛋白质和6%总脂肪,并且还含有大量的维生素、脂肪酸、     

An awareness campaign decreases distracted driving among hospital employees at a rural trauma center

Abstract

Objective: To evaluate whether an educational campaign on distracted driving will have an impact in a given community.

Methods: Investigators were stationed in an employee parking lot of a 256-bed hospital to determine baseline distracted driving followed by a 4-week hospital-wide distracted-driving awareness campaign. The campaign included signs/posters in the hospital, a booth outside of the cafeteria with flyers, a large banner in the employee lot and an opportunity for people to sign a pledge form to drive distraction free. The same employee lot was observed at the same time of the day to re-assess distracted driving immediately following the campaign. The observations were repeated again one year later to evaluate the short and long-term impact of the campaign.

Results: A total of 485 vehicles were observed pre-campaign, identifying 170 (35%) distracted drivers at baseline. The awareness campaign resulted in 525 people pledging to drive distraction free. Following the campaign, 495 vehicles were observed and the number of distracted drivers was 64 (12.9%), showing a significant decrease in the number of distracted drivers by 22.1% (p?<?0.01). One year later, 530 drivers were observed with 150 (28%) displaying one form of distraction.

Conclusions: A local distracted driving educational campaign resulted in a significant decrease in the number of distracted drivers immediately following the campaign. However, one year after the campaign, there was an increase in distracted driving. The proportion of distracted drivers was still significantly lower than the initial rate of distracted-drivers.     

Running Out of Water! Developing a Message Typology and Evaluating Message Effects on Attitude Toward Water Conservation

In three phases, this study identifies and evaluates the major messages being used in communication campaigns focused on the ongoing drought in California. A literature review in Phase 1 resulted in a typology of 12 message strategies. Following this typology, trained coders in Phase 2 evaluated water conservation messages (N?=?100) to determine whether each message utilized one or multiple strategies. The results revealed various frequencies of strategy application; and a correlational analysis rendered a pattern of strategy use in combinations. Phase 3 focused on a controlled message experiment applying the three most relevant strategies: conservation tips, loss aversion, and evidence of drought. Analysing data sampled from California residents (N?=?180), conservation messages, regardless of the strategy, led to attitude change in a negative direction. Additional analyses revealed interesting patterns of combinatorial strategy effects. The results call for a re-examination of message strategies as they may lead to several unfavourable outcomes.     

Evaluating Flow Metric‐Based Stream Classification Systems to Support the Determination of Ecological Flows in North Carolina

Hydroecological classification systems are typically based on an assemblage of streamflow metrics and seek to divide streams into ecologically relevant classes. Assignment of streams to classes is suggested as an initial step in the process of establishing ecological flow standards. We used two distinct hydroecological river classification systems available within North Carolina to evaluate the ability of a hydrologic model to assign the same classes as those determined by observed streamflows and to assess the transferability of such systems to ungaged streams. Class assignments were examined by rate of overall matches, rate of class matches, spatial variability in matches, and time period used in class assignment. The findings of this study indicate assignments of stream class: (1) are inconsistent among different classification systems; (2) differ between observed and modeled data; and (3) are sensitive to the period of record within observed data. One clear source of inconsistency/sensitivity in class assignments lies with the use of threshold values for metrics that distinguish stream classes, such that even small changes in metric values can result in different class assignments. Because these two hydroecological classification systems are representative of other classification systems that rely on quantitative decision thresholds, it can be surmised that the use of such systems based on stream flow metrics is not a reliable approach for guiding ecological flow determinations.     

Spatiotemporal Variability of Snow Depletion Curves Derived from SNODAS for the Conterminous United States, 2004‐2013

Assessment of water resources at a national scale is critical for understanding their vulnerability to future change in policy and climate. Representation of the spatiotemporal variability in snowmelt processes in continental‐scale hydrologic models is critical for assessment of water resource response to continued climate change. Continental‐extent hydrologic models such as the U.S. Geological Survey National Hydrologic Model (NHM) represent snowmelt processes through the application of snow depletion curves (SDCs). SDCs relate normalized snow water equivalent (SWE) to normalized snow covered area (SCA) over a snowmelt season for a given modeling unit. SDCs were derived using output from the operational Snow Data Assimilation System (SNODAS) snow model as daily 1‐km gridded SWE over the conterminous United States. Daily SNODAS output were aggregated to a predefined watershed‐scale geospatial fabric and used to also calculate SCA from October 1, 2004 to September 30, 2013. The spatiotemporal variability in SNODAS output at the watershed scale was evaluated through the spatial distribution of the median and standard deviation for the time period. Representative SDCs for each watershed‐scale modeling unit over the conterminous United States (n = 54,104) were selected using a consistent methodology and used to create categories of snowmelt based on SDC shape. The relation of SDC categories to the topographic and climatic variables allow for national‐scale categorization of snowmelt processes.     

Assessing Effectiveness of National Flood Policy Through Spatiotemporal Monitoring of Socioeconomic Exposure1

Abstract: After a century of evolving flood policies, there has been a steady increase in flood losses, which has partly been driven by development in flood prone areas. National flood policy was revised in 1994 to focus on limiting and reducing the amount of development inside the 100‐year floodplain, with the goal of decreasing flood losses, which can be measured and quantified in terms of population and property value inside the 100‐year floodplain. Monitoring changes in these measurable indicators can inform where and how effective national floodplain management strategies have been. National flood policies are restricted to the spatial extent of the 100‐year floodplain, thus there are no development regulations to protect against flooding adjacent to this boundary. No consistent monitoring has been undertaken to examine the effect of flood policy on development immediately outside the 100‐year floodplain. We developed a standardized methodology, which leveraged national data to quantify changes in population and building tax value (exposure). We applied this approach to counties in North Carolina to assess (1) temporal changes, before and after the 1994 policy and (2) spatial changes, inside and adjacent to the 100‐year floodplain. Temporal results indicate the Piedmont and Mountain Region had limited success at reducing exposure within the 100‐year floodplain, while the Coastal Plain successfully reduced exposure. Spatially, there was a significant increase in exposure immediately outside the 100‐year floodplain throughout North Carolina. The lack of consistent monitoring has resulted in the continuation of this unintended consequence, which could be a significant driver of increased flood losses as any flood even slightly higher than the 100‐year floodplain will have a disproportionately large impact since development is outside the legal boundary of national flood policy.     

Reducing Streamflow Forecast Uncertainty: Application and Qualitative Assessment of the Upper Klamath River Basin,Oregon1

Abstract: The accuracy of streamflow forecasts depends on the uncertainty associated with future weather and the accuracy of the hydrologic model that is used to produce the forecasts. We present a method for streamflow forecasting where hydrologic model parameters are selected based on the climate state. Parameter sets for a hydrologic model are conditioned on an atmospheric pressure index defined using mean November through February (NDJF) 700‐hectoPascal geopotential heights over northwestern North America [Pressure Index from Geopotential heights (PIG)]. The hydrologic model is applied in the Sprague River basin (SRB), a snowmelt‐dominated basin located in the Upper Klamath basin in Oregon. In the SRB, the majority of streamflow occurs during March through May (MAM). Water years (WYs) 1980‐2004 were divided into three groups based on their respective PIG values (high, medium, and low PIG). Low (high) PIG years tend to have higher (lower) than average MAM streamflow. Four parameter sets were calibrated for the SRB, each using a different set of WYs. The initial set used WYs 1995‐2004 and the remaining three used WYs defined as high‐, medium‐, and low‐PIG years. Two sets of March, April, and May streamflow volume forecasts were made using Ensemble Streamflow Prediction (ESP). The first set of ESP simulations used the initial parameter set. Because the PIG is defined using NDJF pressure heights, forecasts starting in March can be made using the PIG parameter set that corresponds with the year being forecasted. The second set of ESP simulations used the parameter set associated with the given PIG year. Comparison of the ESP sets indicates that more accuracy and less variability in volume forecasts may be possible when the ESP is conditioned using the PIG. This is especially true during the high‐PIG years (low‐flow years).     

The Effectiveness of Contrasting Protected Areas in Preventing Deforestation in Madre de Dios, Peru

Accurate monitoring of the effectiveness of protected areas (PAs) in decreasing deforestation is increasingly important given the vital role of forest protection in climate change mitigation. Recent studies on PA effectiveness have used remote-sensing imagery to compare deforestation rates within PAs to surrounding areas. However, remote-sensing data used in isolation provides limited information on the factors contributing to effectiveness. We used landscape-modelling techniques to estimate the effectiveness of ten PAs in Madre de Dios, Peru. Factors influencing PA effectiveness were investigated using in situ key-informant interviews. Although all of the PAs studied had positive effectiveness scores, those with the highest scores were ecotourism and conservation concessions, where monitoring and surveillance activities and good relations with surrounding communities were reported as possible factors in decreasing deforestation rates. Native community areas had the lowest scores, with deforestation mainly driven by internal resource use and population growth. Weak local governance and immigration were identified as underlying factors decreasing the effectiveness of protection, whereas good relations with surrounding communities and monitoring activity increased effectiveness. The results highlight the need to combine remote sensing with in situ information on PA management because identification of drivers and deterrents of deforestation is vital for improving the effectiveness of protection.     

Comparing domestic versus imported apples: A focus on energy use

GOAL, SCOPE AND BACKGROUND: The issue of whether food miles are a relevant indicator for the environmental impacts associated with foods has received significant attention in recent years. It is suggested here that issues other than the distance travelled need to be considered. The argument is presented by illustrating the case for the provision of apples. MATERIALS AND METHODS: The effects of variability in primary energy requirements for apple cultivation and for other life cycle stages, seasonality (timing of consumption) and loss of produce during storage are studied in this paper, by comparing apples from different supplier countries for consumption in Europe. RESULTS: Data sources for primary energy use (PEU) of apple production are identified ranging from 0.4-3.8 MJ/kg apples for European and Southern American countries and 0.4-0.7 MJ/kg for New Zealand. This variability is related to different yields and producer management practices in the different countries. Storage loss may range from 5% to 40% for storage periods between 4 and 10 months, and this has a significant effect on the results (e.g. increasing the total PEU by 8-16% when stored for 5-9 months in Europe as compared with a no loss and no storage situation). The storage periods and related storage losses change markedly through the year for imported (i.e. non-European) versus European apples. DISCUSSION: The timing of consumption and related storage losses need to be included in the assessment, as this affects the order of preference for locally sourced versus imported apples. The variability in energy requirements in different life cycle stages, but particularly for the fruit production stage, is also significant in this comparative analysis. CONCLUSIONS: Overall, it seems that there are similarities in the total PEU ranges for European and New Zealand apples during the Southern Hemisphere's apple season (European spring and summer). However, during the European autumn and winter (Northern Hemisphere apple season) PEU values are generally higher for apples imported from the Southern Hemisphere compared with European apples consumed in Europe. However, this latter observation may not hold true where apples for consumption in one European country are imported from another European country, because energy use for road transportation has a significant influence on the result. RECOMMENDATIONS AND PERSPECTIVES: Future studies comparing alternative sources of fresh produce need to account for ranges of data for the fruit production and storage stages, which reflect the seasonality of production.