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541.
Rachel I. Massey 《Journal of Cleaner Production》2011,19(5):505-516
The Toxics Use Reduction Act (TURA) model is widely cited as an effective blend of mandatory and voluntary components, and is considered a model nation-wide and internationally. There is ample documentation of the reductions in toxic chemical use achieved by Massachusetts facilities under TURA. The present study was designed to gather other information about the experience of these facilities. Through an online survey and telephone interviews, the study investigated how these facilities are achieving toxics use reduction, how TURA affects internal company dynamics, what benefits and difficulties facilities experience, and how their experiences in the program have changed over time. Survey results indicate that the benefits experienced most frequently by facilities subject to TURA requirements are increased management attention to environmental practices; improved worker health and safety; and financial savings. Most frequently cited obstacles to TUR implementation are technical feasibility problems; financial costs; concerns about product quality; and customer requirements. Survey results also indicate that the TUR planning process is most useful in the first and second planning cycles, although most respondents indicated that they sometimes identify useful TUR options in subsequent planning cycles as well. Over all, the results indicate that facilities are continuing to experience significant benefits from the TURA program, while they also continue to face some challenges. These results provide a snapshot of the experience of Massachusetts facilities 20 years since the inception of the TURA program. They also provide baseline information that will be useful for later evaluations of the effects of statutory changes to TURA adopted in 2006 and implemented in subsequent years. The study also included a preliminary assessment of the experience of Massachusetts municipal agencies, community organizations, small business associations and others that receive assistance from the TURA program. 相似文献
542.
Daniel-Mkpume Cynthia Chikodi Ahaiwe Rachel Chinwendu Ifenatuorah Chigozie Lucas Ike-Eze Ikechukwu Christian Ezema Aigbodion Victor Sunday Egoigwe Sochima Vincent Okonkwo Emenike George 《Journal of Material Cycles and Waste Management》2022,24(2):680-691
Journal of Material Cycles and Waste Management - This study contributes towards showing the potential end-of-life application of common wastes namely: Waste Toner powder (WTP) and African star... 相似文献
543.
A Hydrological Model for Predicting the Effects of Dams on the Shoreline Vegetation of Lakes and Reservoirs 总被引:4,自引:0,他引:4
/ The species richness of shoreline vegetation of unregulated lakes in Nova Scotia, Canada, is known to increase as a function of catchment area, a topographic variable governing water level fluctuations. Predictions based on catchment area however, fail to account for richness patterns at the margins of lakes enlarged by dams. Here, we compare the vegetation and hydrological regimes of regulated and unregulated systems. Hydrological regimes of regulated systems deviated from natural systems of similar catchment area by being either hypovariable or hypervariable for both within-year and among-year fluctuations in water level. Plant communities of dammed systems were less diverse, contained more exotic species, and were, with one exception, devoid of rare shoreline herbs. Data from "recovering," or previously dammed systems indicated that shoreline communities can be restored upon return of the appropriate hydrological regime. Using observed within-year and among-year water level fluctuation data, we propose a general model for the maintenance or restoration of diverse herbaceous wetlands on shorelines of temperate lakes or reservoirs. Managers can manipulate the within-year water level variation within prescribed limits (1-2 m), while ensuring that among-year variation (SD of summer levels) is less than 25% of within-year variation. This preliminary model is based on data from low-fertility, temperate lakes in river systems. To calibrate the model, plant community data from other regions are needed, as are long-term water-level data for unregulated lakes, data which are essential but largely lacking in many areas.KEY WORDS: Catchment area; Regulated lakes; Shoreline restoration; Rare plants; Exotic plants; Diversity 相似文献
544.
M. R. Pack A. Clyde Hill 《Journal of the Air & Waste Management Association (1995)》2013,63(4):166-167
Tests were conducted to determine the limitations of glass fiber filters in sampling atmospheric hydrogen fluoride. Filters without latex binder were more efficient collectors than those with the binder. Up to 75 μg F/in.2 of filter area was collected by a single filter before the loss reached 5 percent. Two filters, one behind the other, collected over 250 μg F/in.2 of filter area before loss through them reached five percent. By controlling the sampling rate and time to avoid exceeding the saturation limit, it is possible to use glass fiber filters for sampling over a wide range of fluoride concentrations. 相似文献
545.
Vagisha Pruthi Nimrah Abbasi Varsha Thakur Shiri Shinar Anne O’Connor Rachel Silver Tasha Simpson Tim Van Mieghem 《黑龙江环境通报》2023,43(7):881-888
Objective
Ultrasound assessment of the fetal anatomy and fetal echocardiography are feasible in the first trimester of pregnancy. This study was designed to assess the performance of a comprehensive fetal anatomy assessment in a high-risk population at a tertiary fetal medicine unit.Methods
A retrospective review of high-risk patients undergoing comprehensive fetal anatomy ultrasound assessment between 11 weeks and 13 + 6 weeks of gestation was conducted. Findings of the early anatomy ultrasound scan were compared with those of the second trimester anatomy scan, and birth outcomes or post-mortem results.Results
Early anatomy ultrasounds were performed in 765 patients. The sensitivity of the scan for detecting fetal anomalies compared to the birth outcome was 80.5% (95% CI 73.5–86.3) and specificity was 93.1% (95%CI 90.6–95.2). Positive and negative predictive values were 78.5% (95% CI 71.4–84.6) and 93.9% (95% CI 91.4–95.8), respectively. The most missed and overdiagnosed abnormalities were ventricular septal defects. The second trimester ultrasound had sensitivity of 69.0% (95% CI 55.5–80.5) and specificity of 87.5% (95% CI 84.3–90.2).Conclusions
In a high-risk population, early assessments had similar performance metrics as the second trimester anatomy ultrasound. We advocate for a comprehensive fetal assessment in the care of high-risk pregnancies. 相似文献546.
Seasonal snow is among the most important factors governing the ecology of many terrestrial ecosystems, but rising global temperatures are changing snow regimes and driving widespread declines in the depth and duration of snow cover. Loss of the insulating snow layer will fundamentally change the environment. Understanding how individuals, populations, and communities respond to different snow conditions is thus essential for predicting and managing future ecosystem change. We synthesized 365 studies that examined ecological responses to variation in winter snow conditions. This research encompasses a broad range of methods (experimental manipulations, measurement of natural snow gradients, and long-term monitoring), locations (35 countries), study organisms (plants, mammals, arthropods, birds, fish, lichen, and fungi), and response measures. Earlier snowmelt was consistently associated with advanced spring phenology in plants, mammals, and arthropods. Reduced snow depth often increased mortality or physical injury in plants, although there were few clear effects on animals. Neither snow depth nor snowmelt timing had clear or consistent directional effects on body size of animals or biomass of plants. However, because 96% of studies were from the northern hemisphere, the generality of these trends across ecosystems and localities is also unclear. We identified substantial research gaps for several taxonomic groups and response types; research on wintertime responses was notably scarce. Future research should prioritize examination of the mechanisms underlying responses to changing snow conditions and the consequences of those responses for seasonally snow-covered ecosystems. 相似文献
547.
Area protection is a major mechanism deployed for environmental conservation in Antarctica. Yet, the Antarctic protected areas network is widely acknowledged as inadequate, in part because the criteria for area protection south of 60°S are not fully applied. The most poorly explored of these criteria is the type locality of species, which provides the primary legal means for Antarctic species-based area protection and a method for conserving species even if little is known about their habitat or distribution. The type locality criterion has not been systematically assessed since its incorporation into the Protocol on Environmental Protection to the Antarctic Treaty in 1991, so the extent to which the criterion is being met or might be useful for area protection is largely unknown. To address the matter, we created and analyzed a comprehensive database of Antarctic type localities of terrestrial and lacustrine lichens, plants, and animals. We compiled the database via a literature search of key taxonomic and geographic terms and then analyzed the distance between type localities identifiable to a ≤ 25km2 resolution and current Antarctic Specially Protected Areas (ASPAs) and human infrastructure. We used a distance-clustering approach for localities outside current ASPAs to determine candidate protected areas that could contain these unprotected localities. Of the 386 type localities analyzed, 108 were within or overlapped current ASPAs. Inclusion of the remaining 278 type localities in the ASPA network would require the designation of a further 105 protected areas. Twenty-four of these areas included human infrastructure disturbance. Given the slow rate of ASPA designation, growing pace of human impacts on the continent, and the management burden associated with ASPAs, we propose ways in which the type locality criterion might best be deployed. These include a comprehensive, systematic conservation planning approach and an alternative emphasis on the habitat of species, rather than on a single locality. 相似文献