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291.
Summary The sex pheromone of the grain aphid,Sitobion avenae (Fab.), is identified as (4aS,7S,7aR)-nepetalactone, for which specific olfactory cells are located in the secondary rhinaria of the male antenna. The related (1R,4aS,7S,7aR)-nepetalactol was not produced by females in significant amounts (ca 10,000-fold less than the nepetalactone), although cells in the male antenna were found that responded specifically to this compound. Behavioural activity in the linear track ol-factometer showed attraction of males to the nepetalactone, but not to the nepetalactol.  相似文献   
292.
Host-plant leaf surface compounds influencing oviposition in Delia antiqua   总被引:1,自引:0,他引:1  
Summary. Delia antiqua (Diptera: Anthomyiidae) females lay eggs between the leaves of onion plants or in the soil around the base of the plants, then the maggots feed on the onion bulb and roots causing rapid secondary infection by fungi and bacteria. It is well known that the first sensory modality used by the onion fly is vision, therefore the shape (vertical narrow cylinders) and colour (yellow) of the plant play a crucial role in the recognition of a potential host plant. In the past it has been shown that n-dipropyl disulfide (Pr2S2), a typical component of onion volatiles, is an important chemical host plant cue. We extracted host leaf surface to verify if Pr2S2 is the major chemical oviposition stimulant and to determine if other as yet unknown substances may play a role in host-plant selection. We confirmed that the females laid more eggs around onion plants with leaves than when only the onion bulb was present and that the odour of chopped onion stimulates oviposition. Extraction of the surface of onion leaves revealed that only the apolar fraction contained substances that stimulate egg-laying in D. antiqua. GC-EAD analysis indicated that a minor constituent, Pr2S2, is perceived by the olfactory receptor on the antennae of the onion fly females. This confirmed the importance of Pr2S2 as oviposition stimulant. Contact with the polar fraction did not stimulate egg-laying behaviour in this Delia species. We discuss the oviposition strategy of D. antiqua in comparison with its closely related species, D. radicum, in which the oviposition behaviour is stimulated mainly through contact with the cabbage leaf surface and only partially by the host volatiles.  相似文献   
293.
This study used structural equation modelling to examine the effects of socio-demographic variables and outdoor recreation participation on pro-environmental behaviour (PEB) among an ethnically diverse population of adult state-park visitors near Atlanta, Georgia, USA (N?=?319). Data collected through intercept surveys at three state parks were used to examine interactions among potential predictors of PEB, including socio-demographics (ethnicity, gender, education, and income), outdoor recreation participation (during childhood and adulthood), and environmental value orientations (biocentric and anthropocentric). The best fitting model accounted for 40% of the variance in self-reported PEB and indicated the strongest positive relationship between adult outdoor recreation participation and PEB (β?=?0.54, t?=?5.70). Biocentric and anthropocentric value orientation scores were also significant antecedents of PEB (β?=?0.17, t?=?1.99, and β?=?0.19, t?=?2.56, respectively), and both were influenced by socio-demographic variables. Overall, results suggest that a diverse public's environmental ethos and propensity to engage in PEBs could be influenced by outdoor recreation opportunities.  相似文献   
294.
Introduction: Modern approaches to Occupational Health and Safety have acknowledged the important contribution that continuous improvements to working conditions can make to the motivation of employees, their subsequent performance, and therefore to the competitiveness of the company. Despite this fact, organizational change initiatives represent a path less traveled by employees. Specialized literature has drawn on the fact that employees’ satisfaction presents both the foundation and catalyst for effective implementation of improvements to working conditions. Method: This paper conceptualizes the alignment of employees through measurement of job satisfaction and uses the Bayesian Network to assess the influence of human factors, particularly the cognitive, emotional, and behavioral aspects. Toward this aim, the Bayesian Network is evaluated through a cross-validation process, and a sensitivity analysis is then conducted for each influential dimension: emotional, cognitive, and behavioral. Results: The results reveal that these three dimensions are interrelated and have a direct influence on job satisfaction and employees’ alignment during the organization change. Further, they suggest that the best strategy for enhanced alignment and smooth conduct of organizational changes is simultaneous enhancement of the three dimensions. Practical applications: This study shows the influence of emotional, cognitive, and behavioral dimensions on job satisfaction and employees’ alignment during the organizational change. Furthermore, it elaborates the way to develop efficient and effective strategies for a successful change implementation and sustained alignment.  相似文献   
295.
Practitioners and academic researchers increasingly look to evaluation of health impact assessment (HIA) to improve its practice, its efficiency and its legitimacy. Evaluation is also used to account to policy-makers, who express doubts that the benefits of HIA justify its costs. Until recently evaluation of HIA focused on instrument design and procedures but now the focus needs to shift to analysis of the interaction of HIA and decision-making. Multiple case studies have been applied to identify the conditions in which HIA produces the desired benefits. These studies used analytical concepts derived from the literature on evaluation, knowledge utilization, science of sociology and knowledge management.This paper describes a case study in which the strategic motives of the decision-makers affected the impact of an HIA. This HIA comprised of a quantitative environmental model ‘City & Environment’ that was used to assess environmental health impacts of an urban reconstruction plan in a Dutch city. The evaluation of the HIA shows that the decision to follow the recommendations of the HIA was part of a damage control strategy. The more HIA goals deviate from the policy problem and the less HIA is embedded in institutional procedures, then the more HIA impact will be subject to strategic decision-making behaviour. Appropriate cognitive and social strategies are needed to avoid ‘negative learning’ in those the HIA seeks to influence.  相似文献   
296.
Two non-lethal responses, avoidance andimmobility, were observed for thefreshwater gastropod Potamopyrgusantipodarum on exposure to dissolvedarsenic (As) as arsenate (As(V)) orarsenite (As(III)). Two differentpopulations of P. antipodarum, onewith a long history of exposure todissolved As from geothermal fluids andthe other with minimal exposure, werecompared to test for adaptation to As. Both snail populations avoided dissolvedAs(III), the more toxic form, at lowerconcentrations than As(V). As(V), theless toxic form, was avoided by both snailpopulations at much lower concentrationsthan those at which the snails becameimmobile. In contrast, the concentrationsof As(III) which caused avoidance werealmost the same as those which causedimmobility, implying that avoidance may notbe an effective response to protect thesesnails from exposure to As(III). Snailsfrom the exposed population avoided As(V)at about 20% of the concentration thatwas avoided by the snails from theunexposed population. At higherconcentrations of As(V) which causedimmobility, this difference in sensitivitypersisted up to an exposure time of 48 hours. After 96 hours exposure, however,both populations showed similarsensitivity. Snails from the exposedpopulation were more sensitive to As(III),both avoiding the As and becoming immobileat lower concentrations than were observedfor the same responses in the snails fromthe unexposed population. We suggest thatthe differences in sensitivity between thetwo populations could have been the resultof the higher soft body As burden of theexposed snails at the start of thelaboratory experiments.  相似文献   
297.
Summary. Breeding burrows of Parastizopus armaticeps armaticeps, a fossorial desert tenebrionid beetle, are cleptoparasitised by the closely related Eremostibes opacus. Gas chromatographic analyses show a high congruity of the cuticular hydrocarbons of both species. We compare these hydrocarbon patterns with those of four other Stizopina species and the Scaurini Herpiscius sommeri. In a bioassay, dummies treated with cuticular hydrocarbon extracts of E. opacus and the P. a. bifidus parasite E. bushmanicus were mostly ignored by P. a. armaticeps, whereas dummies with applied extracts of the remaining species were heavily attacked. We show that there is a correlation between agonistic behaviour of P. a. armaticeps towards the intruder and the chemical similarity of the cuticular hydrocarbons of the two species. Furthermore, we produced quantitatively modified hydrocarbon patterns of E. barbatus by changing the temperature at which this species was kept. The new 30 °C type was chemically similar to E. opacus, and was frequently ignored by P. a. armaticeps, whereas a reduction of the temperature to 20 °C only had minor effects on the hydrocarbon pattern. Furthermore, we show that the addition of one single component, heptacosane, to the cuticular hydrocarbon extract of E. opacus alters the host’s reaction. We discuss the role of cuticular hydrocarbons for the recognition of this host-parasite system and the relevance of quantitative characters in the hydrocarbon pattern for the discrimination of the host.  相似文献   
298.
生态环境监测是生态文明建设的重要支撑。在设区市级环境监测监控能力普遍较弱、生态环境保护压力巨大的双重背景下,编制设区市生态环境监测监控规划具有重要意义。在调查了江苏省部分设区市环境监测监控规划的基础上,总结了规划编制在监测监控网络建设、监测监控能力建设、质量管理、大数据应用建设、人才队伍建设等方面的主要内容,针对规划中普遍存在的组织架构不清晰、特色发展定位不明确、环境监测监控融合发展谋划不足、项目建设可行性论证不够等关键问题,提出应理顺组织架构、明确特色发展定位、加强环境监测监控一体化发展谋划、加强项目建设可行性论证等对策建议,以期为今后的规划编制工作提供相关借鉴。  相似文献   
299.
企业生产事故的发生大部分是由于人的不安全行为造成的,而人的不安全行为基本上是由于人的不良习惯所引起,因此养成良好的作业习惯,是降低企业生产事故率的决定因素。为了从理论上阐明人的习惯养成规律,笔者首次提出了应用于企业安全生产管理的习惯养成理论——行为路径管理体系:即首先设定一个清晰的行为路径,通过学习或培训并进行反复实践以及过程纠偏的一系列管理活动,最终达到习惯养成的目的。在企业应用行为路径管理体系的过程中,设定作业路径必须达到四个要求:精细化、程序化、标准化以及在实施过程中的不断优化;在培训阶段,必须使被培训者充分掌握设定的作业路径;在过程纠偏阶段,必须把握好代价原则;在实践阶段,必须有一定的时间保障和激励措施。  相似文献   
300.
Environmental art can be used by government as an engaging medium to encourage pro-environmental behaviour and a sense of place at a grassroots level. By stimulating discussion and reflection, environmental art offers an imaginative format to promote environmental engagement. In this case, by placing artworks in nature, a community's focus was drawn to the beauty of their everyday environment and the ideas communicated by the works, in an effort to encourage environmental awareness and stewardship. This study explores audience responses to Floating Land – a local-government-initiated environmental art festival held in the Noosa Biosphere in Australia. A multi-layered perspective of the festival's impact on pro-environmental behaviours and sense of place was investigated via questionnaires administered to the audience, workshop participants and local residents. Data offered insights into attitude differences between those who intended to change their behaviour and those who did not; understandings about the influence of workshop facilitators; and revelations about a community finding opportunities to re-imagine their place through environmental art. Recommendations are offered as a way for governments to incorporate environmental art into their role of educating for the environment. This study contributes to the under-researched area of audience responses to environmental art by providing qualitative and quantitative analysis that draws out understandings of the impact of art that promotes environmental awareness and a sense of place. The study reveals that Floating Land contributed to reinforcing the essential role of local people in engendering positive change, thus manifesting the aims of the Biosphere Reserve and Agenda 21.  相似文献   
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