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41.
S D Dyer 《Chemosphere》2001,44(3):369-376
Several weight of the evidence approaches for the effects assessment of boron to aquatic organisms have been conducted. The focal point for all of these assessments is the appropriate interpretation of the LC1 for rainbow trout (Oncorhynchus mykiss) from W.J. Birge, J.A. Black, Report No. EPA5601176408. Environmental Protection Agency, Office of Toxic Substances, Washington, DC, 1977, as the LC1 from their studies provided the lowest chronic toxicity values for boron. Other studies by these investigators (W.J. Birge, J.A. Black, Completion Report prepared for the Procter & Gamble Company, Cincinnati, USA, 1981; W.J. Birge, J.A. Black, A.G. Westermann, T.M. Short, S.B. Taylor, M.C. Parekh. Completion Report prepared for the Procter & Gamble Company, Cincinnati, USA, 1984; J.A. Black, J.B. Barnum, W.J. Birge, Chemosphere 26 (1993) 1383-1413) further indicate this species to be particularly sensitive to boron. While weight of the evidence approaches have been necessary for diverse risk assessment needs, they each suffer from potential bias via professional judgment. In order to allay these issues and to update the effects assessment for boron, a probabilistic approach was used. Raw data from the Birge and Black studies were reanalyzed to generate chronic values representative of the adverse effects threshold (e.g., LC10) for several species. A comprehensive list of chronic data from these studies and other studies were combined into a cumulative probability term, allowing for the determination of the fifth percentile protection value, or PNEC0.05. The PNEC0.05 for boron was determined to be at least 1.3 mg B/l.  相似文献   
42.
青岛理工大学安全工程专业课程体系设置模式   总被引:2,自引:0,他引:2  
介绍了我国安全工程专业发展概况、存在的问题及青岛理工大学安全工程专业现状.重点介绍了青岛理工大学安全工程专业课程体系设置情况,提出了2006年安全工程专业课程体系设置调整的构想.  相似文献   
43.
The variation over time of the total annual production of pe and the United Kingdom has been described quantitatively using the exponential smoothing technique. The exercise was repeated on annual mackerel landings for the same two countries. It is suggested that in some cases, the production figure for the current year can be used to simulate the following year's value. The greater variations in South Africa's annual production probably gave rise to the poorer results for these data.  相似文献   
44.
Several authors have found that flowers that are warmer than their surrounding environment have an advantage in attracting pollinators. Bumblebees will forage preferentially on warmer flowers, even if equal nutritional reward is available in cooler flowers. This raises the question of whether warmth and sucrose concentration are processed independently by bees, or whether sweetness detectors respond to higher sugar concentration as well as higher temperature. We find that bumblebees can use lower temperature as a cue to higher sucrose reward, showing that bees appear to process the two parameters strictly independently. Moreover, we demonstrate that sucrose concentration takes precedence over warmth, so that when there is a difference in sucrose concentration, bees will typically choose the sweeter feeder, even if the less sweet feeder is several degrees warmer.  相似文献   
45.
Summary We measured the distance dialects in the dance languages of three honey bee species in Thailand (Apis florea, A. cerana, and A. dorsata), and used these dialects to examine the hypothesis that a colony's dialect is adaptively tuned to enhance efficiency of communication over the distances that its foragers typically fly. in contrast to previous interspecific comparisons in Sri Lanka (Lindauer 1956; Punchihewa et al. 1985), we found no striking dialect differences among the Asian bees in Thailand. The adaptive tuning hypothesis predicts that the foraging ranges of the three species should also be similar, but comparisons of colonial foraging range using the forage mapping technique (Visscher and Seeley 1982) actually revealed marked differences. This raises the possibility that the link between ecology and distance code is more subtle than previously supposed, if a link exists at all. Offprint requests to: F.C. Dyer  相似文献   
46.
为提高企业安全文化建设水平,基于人类协同国际环形和企业安全文化建设水平评价指标设计调查问卷,以赛轮金宇股份有限公司为研究对象,对其企业文化和企业安全文化建设水平进行相关性分析和多元逐步回归分析,探索二者的互动效应,从企业文化角度发掘安全文化建设重点。结果表明,自我实现文化、亲和文化、传统文化、成就文化与企业安全文化建设水平高度正相关,逃避文化则呈现高度负相关,其相关系数(绝对值)均在0.9以上;同时,多元逐步回归分析中,以上5个文化规则均进入回归方程,其标准化回归系数β分别为:0.395、0.182、0.169、0.129、-0.145。因此,这5种文化规则对企业安全文化建设水平具有很高的预测力,是企业安全文化建设的重点所在。  相似文献   
47.
为了研究丙烯酰胺致小鼠睾丸细胞和外周血淋巴细胞DNA的损伤及修复情况,同时比较这两种细胞对丙烯酰胺的敏感性,将雄性昆明种小鼠一次性腹腔注射丙烯酰胺(50mg·kg-1(bw)),在暴露后第1、2、4、6、8、10、12d,分别对其睾丸组织细胞和外周血淋巴细胞DNA损伤进行彗星实验分析.结果表明,暴露结束后每个时间点小鼠睾丸组织细胞、外周血淋巴细胞DNA的迁移率均显著高于阴性对照组,随时间推移两种细胞DNA迁移距离逐渐降低,同一时间点睾丸组织细胞DNA损伤较外周血淋巴细胞DNA损伤更为严重,两者差异显著(p<0.05).以上结果表明,睾丸组织和外周血淋巴细胞可能是丙烯酰胺的作用位点;机体对丙烯酰胺造成的遗传损伤有一定的修复能力;与淋巴细胞相比,睾丸细胞对丙烯酰胺导致的遗传损伤更为敏感.  相似文献   
48.
National and international chemical management programs are assessing thousands of chemicals for their persistence, bioaccumulative and environmental toxic properties; however, data for evaluating the bioaccumulation potential for fish are limited. Computer based models that account for the uptake and elimination processes that contribute to bioaccumulation may help to meet the need for reliable estimates. One critical elimination process of chemicals is metabolic transformation. It has been suggested that in vitro metabolic transformation tests using fish liver hepatocytes or S9 fractions can provide rapid and cost-effective measurements of fish metabolic potential, which could be used to refine bioconcentration factor (BCF) computer model estimates. Therefore, recent activity has focused on developing in vitro methods to measure metabolic transformation in cellular and subcellular fish liver fractions. A method to extrapolate in vitro test data to the whole body metabolic transformation rates is presented that could be used to refine BCF computer model estimates. This extrapolation approach is based on concepts used to determine the fate and distribution of drugs within the human body which have successfully supported the development of new pharmaceuticals for years. In addition, this approach has already been applied in physiologically-based toxicokinetic models for fish. The validity of the in vitro to in vivo extrapolation is illustrated using the rate of loss of parent chemical measured in two independent in vitro test systems: (1) subcellular enzymatic test using the trout liver S9 fraction, and (2) primary hepatocytes isolated from the common carp. The test chemicals evaluated have high quality in vivo BCF values and a range of logK(ow) from 3.5 to 6.7. The results show very good agreement between the measured BCF and estimated BCF values when the extrapolated whole body metabolism rates are included, thus suggesting that in vitro biotransformation data could effectively be used to reduce in vivo BCF testing and refine BCF model estimates. However, additional fish physiological data for parameterization and validation for a wider range of chemicals are needed.  相似文献   
49.
环境会计发展的理念与实践是以实现经济、社会、环境的可持续发展为前提,通过实施环境会计制度,可以使企业准确掌握经营活动的资源消耗、环境负荷,促进其提供环境友好产品及服务,推进经济朝着低碳、绿色、可持续模式发展。日本经过十几年的发展,目前已形成较为完善的环境会计体系。本文通过介绍和分析日本环境会计体系产生的背景、发展变化与作用,探讨我国环境会计体系构筑问题。  相似文献   
50.
Human activities are important drivers of marine ecosystem functioning. However, separating the synergistic effects of fishing and environmental variability on the prey base of nontarget predators is difficult, often because prey availability estimates on appropriate scales are lacking. Understanding how prey abundance at different spatial scales links to population change can help integrate the needs of nontarget predators into fisheries management by defining ecologically relevant areas for spatial protection. We investigated the local population response (number of breeders) of the Bank Cormorant (Phalacrocorax neglectus), a range‐restricted endangered seabird, to the availability of its prey, the heavily fished west coast rock lobster (Jasus lalandii). Using Bayesian state‐space modeled cormorant counts at 3 colonies, 22 years of fisheries‐independent data on local lobster abundance, and generalized additive modeling, we determined the spatial scale pertinent to these relationships in areas with different lobster availability. Cormorant numbers responded positively to lobster availability in the regions with intermediate and high abundance but not where regime shifts and fishing pressure had depleted lobster stocks. The relationships were strongest when lobsters 20–30 km offshore of the colony were considered, a distance greater than the Bank Cormorant's foraging range when breeding, and may have been influenced by prey availability for nonbreeding birds, prey switching, or prey ecology. Our results highlight the importance of considering the scale of ecological relationships in marine spatial planning and suggest that designing spatial protection around focal species can benefit marine predators across their full life cycle. We propose the precautionary implementation of small‐scale marine protected areas, followed by robust assessment and adaptive‐management, to confirm population‐level benefits for the cormorants, their prey, and the wider ecosystem, without negative impacts on local fisheries.  相似文献   
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