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121.
Over the last several decades, the scientific community has replaced the ‘acts of god’ explanations for disasters with a view that disasters are actually ‘acts of nature,’ and more recently, ‘acts of human behavior and decision making.’ Despite the secular orientation of contemporary disaster research, religious beliefs still govern people’s interpretations of natural events across many continents and cultures. Using a case study of a rural Sherpa community in Nepal, this paper responds to the challenge of linking religion and disaster risk in the context of a climate change-induced glacial lake outburst flood hazard. Data collection employed ethnographic techniques including participant observation and 53 interviews with community members. Results indicate that the case study community’s religious belief system influences how they interpret and respond to the glacial lake hazard, although their beliefs co-exist with more scientific interpretations of risk. Rather than being immobilised by their belief system, we found that religious aspects like rituals and prayer can enhance social cohesion and contribute to capacities for coping with fear and uncertainty in this community. We assert that religion can yield valuable resources to glacial lake risk reduction strategies, which will benefit from incorporating social-cultural factors more profoundly.  相似文献   
122.
This study focuses on the inertial oscillation aspect of the nocturnal low-level jet (NLLJ). In the context of the Ekman model solutions, conceptual NLLJ inertial oscillation analytical frameworks proposed by Blackadar in 1957 and Shapiro and Fedorovich and van de Wiel et al. in 2010 are compared. Considering a NLLJ produced via direct numerical simulation over flat terrain with no baroclinic influence as a reference case, the deficiencies of each framework in representing a realistic NLLJ are assessed. The Blackadar theory results in unrealistic wind profiles near the surface. While extensions of Blackadar’s framework by Shapiro and Fedorovich and van de Wiel et al. produce more realistic NLLJs, the simpler approach taken by van de Wiel et al. does not describe the NLLJ wind hodograph at later times sufficiently in qualitative terms.  相似文献   
123.
In the last decade, the U.S. Food and Drug Administration (FDA) has issued several warnings and recalls for food products that exceed FDA standards for lead. Products containing chili peppers and salt were often suspected as sources of lead contamination, and included items such as candy that are routinely investigated. However, products such as hot sauces that contain similar ingredients have not been the focus of evaluations. This study quantified lead concentrations in imported hot sauces, evaluated product compliance to existing United States standards, and calculated potential dietary lead exposure for children using the Integrated Exposure Uptake Biokinetic Model. Finally, recommendations for reducing the risk of lead exposure from hot sauces are provided. Twenty-five (25) bottles of imported hot sauces manufactured in Mexico and South America were purchased in Clark County, Nevada. All hot sauces were analyzed for lead concentrations, pH, and leaded packaging. Hot sauces were analyzed by inductively coupled plasma mass spectrometry and packaging was analyzed using x-ray fluorescence technology. Four brands of hot sauces (16%) exceeded 0.1 ppm lead, the current FDA action level for lead in candy. Hot sauces with lead concentrations >0.1 ppm lead contained salt and were manufactured in Mexico. Subsequent analysis of additional lots of hot sauces exceeding 0.1 ppm lead revealed inconsistent lead concentrations between and within manufacturer lots. The lead concentrations of the plastic hot sauce lids ranged from below the limit of detection to 2,028 ppm lead. There was no association between lead concentrations in hot sauces and pepper type. These results indicate the need for more rigorous screening protocols for products imported from Mexico, the establishment of an applicable standard for hot sauce, and resources to allow for the enforcement of existing food safety policies. The data reported herein represent the first known investigation of lead concentrations in hot sauces.  相似文献   
124.
Intensive agricultural land use imposes multiple pressures on streams. More specifically, the loading of streams with nutrient-enriched soil from surrounding crop fields may deteriorate the sediment quality. The current study aimed to find out whether stream restoration may be an effective tool to improve the sediment quality of agricultural headwater streams. We compared nine stream reaches representing different morphological types (forested meandering reaches vs. deforested channelized reaches) regarding sediment structure, sedimentary nutrient and organic matter concentrations, and benthic microbial respiration. Main differences among reach types were found in grain sizes. Meandering reaches featured larger mean grain sizes (50–70 μm) and a thicker oxygenated surface layer (8 cm) than channelized reaches (40 μm, 5 cm). Total phosphorous amounted for up to 1,500 μg?g?1 DW at retentive channelized reaches and 850–1,050 μg?g?1 DW at the others. While N-NH4 accumulated in the sediments (60–180 μg?g?1 DW), N-NO3 concentrations were generally low (2–5 μg?g?1 DW). Benthic respiration was high at all sites (10–20 g O2 m?2?day?1). Our study shows that both hydromorphology and bank vegetation may influence the sediment quality of agricultural streams, though effects are often small and spatially restricted. To increase the efficiency of stream restoration in agricultural landscapes, nutrient and sediment delivery to stream channels need to be minimized by mitigating soil erosion in the catchment.  相似文献   
125.
The bait-marker iophenoxic acid (IPA) and its derivatives are increasingly used for evaluating and optimizing the cost-effectiveness of baiting campaigns on wildlife, particularly on game species such as the wild boar. We aimed to determine whether concentrations of the three main IPA derivatives ethyl, methyl and propyl-IPA measured on thoracic liquid extracts (TLE) of hunted wild boars may be representative of two exposure doses, 40 and 200 mg, from 20 to 217 days after ingestion. Then we developed a method of detection of the three IPA derivatives by LC/ESI-MS-MS in muscle and liver to evaluate the suitability of these two other tissues for monitoring the marked bait consumption and for measuring available residues in the meat of marked animals. Three semi-captive wild boars received 40 mg of each IPA derivative, three received 200 mg, and three, as controls, did not receive IPA. Blood serum was sampled 20, 197 or 217 days after IPA exposure according to animals and to the derivative. Wild boars were shot by gun after the different times of serum sampling times, and TLE, muscle and liver were sampled. Our results suggest that TLE is not a relevant tissue for quantitatively expressing IPA exposure. Due to interference, no analytical method was validated on TLE containing digestive material. On the other hand, quantifications in the muscle and particularly in the liver could discriminate wild boars that had ingested the two IPA doses from 20 days until 7 months after exposure, especially for the two long term markers ethyl and propyl-IPA. So IPA quantifications in the liver sampled on hunted animals appear to be a reliable tool for monitoring bait consumption in the field at a large scale. Nevertheless, whatever the ingested dose, ethyl- and propyl-IPA concentrations measured in the muscle and the liver of tested animals until 217 days after exposure, remained higher than 0.01 mg/kg, the Maximal Residue Limit (MRL) is recommended for molecules for which no toxicological data are available. Based on the range of IPA residues available in these two tissues, implications for humans consuming marked animals are discussed.  相似文献   
126.
This review article outlines harmful algal bloom (HAB) monitoring practices in New Zealand and highlights the shift from light microscope (LM)-based identification and quantification of the early 1990s to the use of molecular tools to support the HAB monitoring programmes two decades later. Published research and available client information from the monitoring programmes have been reviewed; HAB events and programme changes are highlighted. The current HAB monitoring practices allow for rapid determination of potential biotoxin issues for the shellfish industry and of potential ichthyotoxic events for finfish farmers. The use of molecular tools, including quantitative PCR, has improved risk assessments for those HAB species that are difficult to differentiate to species level using LM. This has enabled rapid feedback to aquaculture managers during HAB events. Tests for biotoxins in flesh remain the regulatory tools for commercially harvested shellfish, but this is supported by the weekly phytoplankton monitoring data. Recreational (non-commercial) shellfish harvesting and commercial finfish aquaculture rely solely on phytoplankton monitoring to assess the biotoxin risk. HAB monitoring in New Zealand continues to maintain internationally recognised standards, and the government-funded research programmes feed the latest knowledge and technical methods into the programmes. The early dependence on light microscopy continues but is now supported by molecular tools, with a view to employing multi-species detection systems in the future. The traditional mouse bioassay test has been fully replaced by chemical tests.  相似文献   
127.
In northeastern Austria, marshlands have been turned into the most productive arable land of the country. As a result, most headwater streams show structurally degraded channels, lacking riparian buffer zones, which are heavily loaded with nutrients from the surrounding crop fields. The present study examines whether longitudinally restricted riparian forest buffers can enhance the in-stream nutrient retention in nutrient-enriched headwater streams. We estimated nutrient uptake from pairwise, short-term addition experiments with NH, NH, PO, and NaCl within reaches with riparian forest buffers (RFB) and degraded reaches (DEG) of the same streams. Riparian forest buffers originated from the conservation of the pristine vegetation or from restoration measures. Hydrologic retention was calculated with the model OTIS-P on the basis of conductivity break-through curves from the salt injections. A significant increase in surface transient storage was revealed in pristine and restored RFB reaches compared with DEG reaches due to the longitudinal step-pool pattern and the frequent occurrence of woody debris on the channel bed. Ammonium uptake lengths were significantly shorter in RFB reaches than in DEG reaches, resulting from the higher hydrologic retention. Uptake velocities did not differ significantly between RFB and DEG reaches, indicating that riparian forest buffers did not affect the biochemical nutrient demand. Uptake of NH was mainly driven by autotrophs. Net PO uptake was not affected by riparian forest buffers. The study shows that the physical and biogeochemical effects of riparian forest buffers on the in-stream nutrient retention are limited in the case of highly eutrophic streams.  相似文献   
128.
Managers of the nearly 0.5 million ha of public lands in North and South Dakota, USA rely heavily on manual measurements of canopy height in autumn to ensure conservation of grassland structure for wildlife and forage for livestock. However, more comprehensive assessment of vegetation structure could be achieved for mixed-grass prairie by integrating field survey, topographic position (summit, mid and toeslope) and spectral reflectance data. Thus, we examined the variation of mixed-grass prairie structural attributes (canopy leaf area, standing crop mass, canopy height, nitrogen, and water content) and spectral vegetation indices (VIs) with variation in topographic position at the Grand River National Grassland (GRNG), South Dakota. We conducted the study on a 36,000-ha herbaceous area within the GRNG, where randomly selected plots (1?km2 in size) were geolocated and included summit, mid and toeslope positions. We tested for effects of topographic position on measured vegetation attributes and VIs calculated from Landsat TM and Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data collected in July 2010. Leaf area, standing crop mass, canopy height, nitrogen, and water content were lower at summits than at toeslopes. The simple ratio of Landsat Band 7/Band 1 (SR71) was the VI most highly correlated with canopy standing crop and height at plot and landscape scales. Results suggest field and remote sensing-based grassland assessment techniques could more comprehensively target low structure areas at minimal expense by layering modeled imagery over a landscape stratified into topographic position groups.  相似文献   
129.
Translating policies about sustainable development as a social process and sustainability outcomes into the real world of social–ecological systems involves several challenges. Hence, research policies advocate improved innovative problem-solving capacity. One approach is transdisciplinary research that integrates research disciplines, as well as researchers and practitioners. Drawing upon 14 experiences of problem-solving, we used group modeling to map perceived barriers and bridges for researchers’ and practitioners’ joint knowledge production and learning towards transdisciplinary research. The analysis indicated that the transdisciplinary research process is influenced by (1) the amount of traditional disciplinary formal and informal control, (2) adaptation of project applications to fill the transdisciplinary research agenda, (3) stakeholder participation, and (4) functional team building/development based on self-reflection and experienced leadership. Focusing on implementation of green infrastructure policy as a common denominator for the delivery of ecosystem services and human well-being, we discuss how to diagnose social–ecological systems, and use knowledge production and collaborative learning as treatments.  相似文献   
130.
Chewing and mouthing behaviors exhibited by pet dogs are likely to lead to oral exposures to a variety of environmental chemicals. Products intended for chewing and mouthing uses include toys and training devices that are often made of plastics. The goal of the current study was to determine if a subset of phthalates and bisphenol A (BPA), endocrine disrupting chemicals commonly found in plastics, leach out of dog toys and training devices (bumpers) into synthetic canine saliva. In vitro assays were used to screen leachates for endocrine activity. Bumper leachates were dominated by di-2-ethylhexyl phthalate (DEHP) and BPA, with concentrations reaching low μg mL−1 following short immersions in synthetic saliva. Simulated chewing of bumpers during immersion in synthetic saliva increased concentrations of phthalates and BPA as compared to new bumpers, while outdoor storage had variable effects on concentrations (increased DEHP; decreased BPA). Toys leached substantially lower concentrations of phthalates and BPA, with the exception of one toy which leached considerable amounts of diethyl phthalate. In vitro assays indicated anti-androgenic activity of bumper leachates, and estrogenic activity of both bumper and toy leachates. These results confirm that toys and training devices are potential sources of exposure to endocrine disrupting chemicals in pet dogs.  相似文献   
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