四氯乙烯胁迫对草鱼抗氧化酶活性的影响及其机理

研究了四氯乙烯(PCE)对草鱼的肝胰脏、肾脏和鳃组织的超氧化物歧化酶(SOD)和过氧化物酶(POD)的影响.结果表明:草鱼肝胰脏SOD活性,在PCE低浓度胁迫时其SOD活性“先升后降”[72h SOD是(6665.84±106.87)U/g·FW,168h SOD是(3021.26±16.96)U/g·FW],高浓度胁迫时“先降后升再降”[24h SOD是(2175.16±185.14)U/g·FW, 96h SOD是(5692.19±44.17)U/g·FW,168h SOD是(1297.70±11.52)U/g·FW];草鱼肾脏SOD活性在PCE所有浓度组胁迫均是“先降后升再降”的趋势;草鱼鳃组织SOD酶活性只有在PCE较低浓度短时间内没有显著变化,其它情况始终降低.在PCE低浓度和中等浓度胁迫时,草鱼肝胰脏POD活性始终降低,较低浓度和高浓度胁迫时肝胰脏POD活性“先降后升再降”;草鱼肾脏POD活性在PCE低浓度胁迫时“先升后降再升又降”的趋势,而高浓度胁迫时“先降后升又降”;PCE对草鱼鳃组织POD活性“先升后降”的趋势.但是草鱼鳃组织的SOD和POD活性明显低于肝胰脏和肾脏组织的SOD和POD活性.     

Interdisciplinary knowledge integration through group model building: recognizing dualities and triadizing the conversation

As part of the inquiry into managing an interdisciplinary research process on adaptive water governance, we investigated the process of group model building (GMB) and, more specifically, the role of Unified Modeling Language (UML) in this process. An analysis of group interaction reveals several tensions in the process of knowledge integration, which can be grouped into three overarching dualities: ‘simplicity versus complexity’, ‘constraining versus containing’ and ‘defining versus refining’. As group members take different positions with regard to these dualities, these represent sources of tension and potential ‘stuckness’ of the GMB. Hence the question arises how the group can manage duality in ways that take the GMB beyond its opposing forces. We suggest that knowledge integration processes may benefit from early recognition of the dualities at hand and strategies aimed at creating ‘thirdness’, including some suggestions on the concrete forms such ‘thirdness’ may take.     

东苕溪鱼类生物完整性评价河流健康体系的构建与应用

以东苕溪流域为研究区域,建立基于鱼类生物完整性指数(IBI)的河流健康评价指标体系.采样点来自2个不同的生态区,共建立了2套不同的IBI评价指标体系和标准.上游支流样点均来自浙闽山地常绿阔叶林生态区,从而建立了东苕溪上游支流的IBI指标体系:即鱼类总物种数(M1)、平鳍鳅科鱼类物种数百分比(M5)、中国土著鱼类物种数百分比(M6)、Shannon-Wiener多样性指数(M7)、无脊椎动物食性鱼类个体百分比(M13)、植食性鱼类个体百分比(M14)、敏感性鱼类个体百分比(M1)7个参数指标.中下游样点均来自长江三角洲城镇及城郊农业生态区,建立了东苕溪中下游区域的IBI指标体系:即鱼类总物种数(M1)、虾虎鱼科鱼类物种数百分比(M4)、中国土著鱼类物种数百分比(M6)、Shannon-Wiener多样性指数(M7)、上层鱼类物种数百分比(M8)、中上层鱼类物种数百分比(M9)、植食性鱼类个体百分比(M14)、借助贝类产卵鱼类物种数百分比(M21)、鱼类总个体数(M22)、畸形、患病鱼类个体数百分比(M23)等10个参数指标.河流健康状态划分为5个健康等级:即“健康”、“一般”、“较差”、“极差”和“无鱼”.应用IBI指标体系评价东苕溪流域的45个观测点的河流健康状况,结果显示东苕溪流域绝大多数河段的健康状况处于“一般”和“较差”水平.2011年,东苕溪中下游河段的健康状态较2010年有所改善,然而上游支流的健康状态较2010年有所下降.     

The first trimester ‘combined test’ for the detection of Down syndrome pregnancies in 4939 unselected pregnancies

The high detection rate (DR) for Down syndrome (DS) pregnancies which can be achieved by measuring fetal nuchal translucency (NT) early in pregnancy can be improved by combining it with placental hormones [pregnancy-associated plasma protein A (PAPP-A) and free β-human chorionic gonadotrophin (fβ-hCG)] and maternal age (‘combined test’). In this study we wanted to assess the DR using the ‘combined test’ in an unselected population of self-referred pregnant women at a false-positive rate (FPR) of about 5%. NT, PAPP-A, fβ-hCG and maternal age were measured in all women with singleton pregnancies who booked for delivery in our hospital from 1 December 1997 to 31 April 2000 and who were between 10 and 13 completed weeks of gestation [crown–rump length (CRL) 35–70 mm]. The specific DS risk was calculated using the computer program Alpha Version 5aa (Logical Medical Systems, London, UK). A total of 4939 women were tested. Out of 14 DS pregnancies that occurred during this period of time, 12 were detected with the test. A total of 246 women had a false-positive test result in a non-DS pregnancy (FPR 5.0%). This makes the ‘combined test’ by far the best test for the detection of DS pregnancies in a low-risk population. The constant increase in maternal age at the time of delivery can also lead to an improved DR if a simple age-dependant protocol for DS detection is used, but only at the price of a much higher number of amniocenteses and subsequent abortions. The DR for DS can be increased much more markedly using the ‘combined test’ with a FPR that still remains at the level as it was in the early 1970s. Copyright © 2002 John Wiley & Sons, Ltd.     

The ISO 14001 certification of a machine-process

Some process machines in industrial manufacturing can be defined machine-process: their operations can be analysed by several points of view independently from the larger manufacturing process where they are included. For a machine-process, an Ems—Environmental management system can be set up and the ISO 14001 certification reached in an ‘earlier application’ way, with the involvement of both supplier/manufacturer and client/user. The ‘earlier certification’ of machine-processes adds new contents to the product, linked to the environment, helping the market of ‘clean technologies’, and fosters the diffusion of ISO 14001 certification among supplying/manufacturing companies and clients/users whose entire process is not yet certified.A case study is presented that has been experienced in Italy. The ‘offer and design’ phase of a port mobile shiploader is completely developed by following the ‘earlier application’ scheme for ISO 14001 certification of a machine process—introduced and explained in the paper. Achieved results are shown, and the perspective of a complete application of the scheme to the following ‘detailed design and assembly’ and ‘operations’ phases of the same machine are outlined. The feasibility of such a new application of ISO 14000 standards is proved, together with its advantages, while the readiness of the market for the new sector of earlier certification of machine-processes is highlighted.     

Prediction of Temperature in Vacuum Arc Remelting in the Presence of Strong Disturbances

A system for predictive, noninvasive temperature measurement in a broad class of manufacturing processes is presented. The system employs a comprehensive, three-tier signal processing algorithm to achieve high accuracy and reliability in the presence of strong disturbances. Temperature estimates are generated by ‘unstructured, shallow knowledge’ based algorithms. The estimation process employs a set of robust features obtained by signal processing that involves constitutive models representing ‘deep knowledge’ about the process dealt with. The application of these models is combined with ‘structured, shallow knowledge’ based techniques. Results obtained in application to the investment casting of titanium, which employs the vacuum arc remelting (VAR) process, are presented.     

“一带一路”沿线国家碳排放:外商直接投资与发展要素的共同影响分析

“一带一路”倡议下,推动绿色低碳发展,共建碳达峰、碳中和目标下国际合作共赢的生态圈,已经成为“一带一路”沿线国家的共识. 本文基于“一带一路”沿线国家1997—2018年的面板数据,通过逐步回归、异质性分析和门槛回归方法探究外商直接投资(FDI)的碳排放效应. 结果显示:①“一带一路”沿线国家FDI显著增加碳排放,体现出“污染天堂”效应. ②我国提出的“一带一路”倡议注重绿色低碳发展,削弱了“一带一路”沿线国家FDI对碳排放的“污染天堂”效应,体现出我国在环境治理特别是应对气候变化方面发挥的引领示范作用. ③经济发展可削弱FDI对碳排放的“污染天堂”效应,然而经济快速发展特别是工业发展可显著增加碳排放. ④政策、创新和发展三类机制均导致FDI的碳排放效应发生显著变化,其中发展机制影响最大,创新机制的碳减排效果相对稳定. ⑤强化环境规制促进了FDI的“污染光环”效应,“一带一路”倡议则推动“一带一路”沿线各国加强了环境规制. 研究显示,为促进“污染光环”效应形成,应深化绿色“一带一路”,利用来自中国投资的低碳化特征,增加与中国的投资往来并提高负有环境责任FDI的比例. “一带一路”沿线各国也应加强绿色低碳科技创新,在此基础上协同政策、创新和发展三类机制,引导FDI投向绿色低碳领域. 此外,还应综合运用环境准入机制和环境经济手段,实现高质量发展.      

Rapid karyotyping in prenatal diagnosis: A comparative study of the ‘pipette method’ and the ‘in situ’ technique for chromosome harvesting

Rapid karyotyping in the second and third trimesters has important implications for the management of pregnancies at risk. From September 1985 to March 1992, 735 amniotic fluid samples sent to our laboratory for rapid karyotyping from 64 different diagnostic centres of the Federal Republic of Germany were included in a comparative study on harvesting for chromosome analysis using the ‘pipette method’ or the ‘in situ’ technique. The average time between preparation of the amniotic fluid and verbal notification of the analysed karyotype was 5·41 days. The ‘pipette method’ needed on average 4·65 days, and the ‘in situ’ technique 5·97 days. In comparison with other more invasive techniques available for rapid karyotyping such as cordocentesis and placental biopsy, amniocentesis and subsequent chromosome harvesting using the ‘pipette method’ and/or the ‘in situ’ technique proved very useful and efficient. The overall incidence of chromosome aberrations was 15·3 per cent. The high rate of structural chromosome aberrations and uncommon aneuploidies found in our investigation (12 per cent) indicates that for rapid karyotyping in the second and third trimesters, conventional cytogenetic techniques cannot be replaced by faster techniques based on fluorescent in situ hybridization on interphase cells in the near future.     

Stimulating learning and innovation in networks for regional sustainable development: the role of local authorities

Inter-organizational collaboration in networks and partnerships is supposed to promote the potential for learning and innovation needed for environmental transformation and sustainable development. This paper aims at exploring the roles of local authorities (LAs) in actor-networks related to regional sustainable development, and examining their potential in stimulating learning and innovation related to sustainable development. From empirical case studies it is suggested that LAs can act as ‘teachers’ or ‘tutors’ in the networks. From further analysis, drawing also from literature on partnerships, innovation management, socio-technical change, and educational science, it is proposed that in the short run both the ‘teacher’ and ‘tutor’ approach would promote incremental innovation rather than the radical system innovations needed for sustainable development. However, there is potential for stimulating more long-term, radical change if the LA takes on the role of a ‘teacher’. This approach may favour close collaboration in long-lived, multi-actor networks with potential to (i) serve as forum for continuous dialogue on sustainable development at a community level, (ii) stimulate experimentation and learning needed for system innovations, and (iii) provide a basis for strategic niche management for development and testing of new technologies.     

How farmers view their job in Pays de Caux,France: Consequences for grassland in water erosion

In Pays de Caux, runoff and erosion frequently generate damages. Ploughing up grassland is one of the causes of their increase. To apprehend this issue, the authors studied the conceptions of a group of farmers, farming the same catchment, through a socio-anthropological approach.According to this analysis, two types of farms are identified: the ‘managers’ looking at the profitability per hectare, and the ‘livestock farmers’, for whom the global income of farming is more important. The latter are severely depreciated, by the others and by themselves, and are generally not taken over. Nevertheless, their grasslands are more steady than the ‘managers’ ones, and their preservation is important to combat erosion.The Common Agricultural Policy (CAP) does not suggest any measures supporting grassland of these ‘small livestock farmers’. Local subsidies could not only support them economically but could also contribute to decrease their depreciation. This may be a way to manage the risk of soil erosion. However, the results are established at the catchment level and further enquiries are needed to extend them. It is possible to build a network of places in Europe, with the aim of thinking propositions at the CAP level.     

Institutionalising social learning: Towards systemic and adaptive governance

This paper critically examines how public policy makers limit policy and other institutional design choices by a failure to appreciate (i) how situations may be characterised or framed; (ii) how practices that generate neologisms (invented terms or concepts) or reify (make into a thing) abstract concepts can displace understandings, and (iii) the epistemological bases of governance mechanism choices. An inquiry into the coining of the neologisms ‘wicked’ and ‘tame’ problems is reported and the implications for research and policy practice explored. As practices, neologising, reifying, categorising and typologising have unintended consequences – they remove us from the primary experiences and underlying emotions that provided the motivation for formulating these concepts in the first place. The failure to institutionalise the understandings and experiences that sit behind the invention of the terms ‘wicked’ and ‘tame’ problems (or similar framing choices such as ‘problematique’, ‘messes’, ‘lowland real-life swamps’, ‘resource dilemmas’ or ‘complex adaptive systems’) present systemic constraints to institutionalising social learning as an alternative yet complementary governance mechanism within an overall systemic and adaptive governance framework. Ultimately situations usefully framed as ‘wicked’,’ such as water managing and climate change are problems of relationship – of human beings with the biosphere. Re-framings, such as institutions as social technologies and other research and praxis traditions concerned with the breakdown of relationships may offer ways forward in the purposeful designing and crafting of more effective institutions.     

Governance of sustainable transitions: about the 4(0) ways to change the world

Transitions are radical system innovations that usually take 1–2 generations. Using Cultural Theory as a heuristic, this paper presents four archetypical approaches to transition management. The fatalist approach refrains from transition management (motto: ‘First, disaster must happen’). The system is in a stalemate that no experiment or hierarchy can break; external events must bring the window of opportunity for change. The hierarchic approach relies on a dominant actor coalition to steer change (motto: ‘Let's put a man on the moon!’). The individualist approach relies mainly on changing the financial ground rules (motto: ‘Sustainability through the market’). Finally, the egalitarian approach relies on process management, doing experiments, etc. (motto: ‘A good transition arena will solve it all’). This approach makes sense if the situation is not clear enough to be managed via one of the other approaches, and there is a clearly identifiable learning objective.     

Natal departure timing from spatially varying environments is dependent of individual ontogenetic status

Natal departure timing represents one of the first crucial decisions for juveniles born in spatially varying environments that ultimately disappear, but our knowledge on its determinants is limited. The present study aimed at understanding the determinants of juvenile natal departure by releasing individually tagged juvenile pike (Esox lucius L.) with variable body size and trophic position in a temporary flooded grassland. Specifically, we investigated whether natal departure depends on individual competitive status (‘competition hypothesis’), physiological tolerance to environmental conditions (‘physiological hypothesis’) or individual trophic position and the spatial heterogeneity of trophic resources (‘trophic hypothesis’). The results indicated that departure timing was negatively correlated with body size at release, showing that the dominance status among competing individuals was not the main trigger of juvenile departure. A positive correlation between departure timing and individual body size at departure was observed, suggesting that inter-individual variability in physiological tolerance did not explain departure patterns. While individual growth performances were similar irrespective of the timing of natal departure, stable isotope analyses revealed that juveniles with higher trophic position departed significantly earlier than individuals with lower trophic position. Therefore, the trade-off driving the use of spatially varying environments was most likely dependent upon the benefits associated with energetic returns than the costs associated with inter-individual competition or physiological stress. This result highlighted how ontogeny, and particularly ontogenetic niche shift, can play a central role in juvenile’s decision to depart from natal habitats in a predatory species.     

Genetic amniocentesis: 505 cases performed before the sixteenth week of gestation

Between May 1987 and November 1988, 505 early amniocentesis within the 15th week of gestation were performed at the First Department of Obstetrics and Gynaecology,‘L. Mangiagalli’ of the University of Milan and at the Department of Obstetrics and Gynaecology of ‘Gaslini’ hospital in Genoa. A total number often abnormal fetal karyotypes were diagnosed. In addition, one case of pseudomosaicism (not confirmed on fetal blood) and one case of osteogenesis imperfecta type II (observed at ultrasound examination) were also detected. Eleven pregnancies were therefore terminated because of an abnormal fetus. Out of 494 pregnancies (excluding terminated pregnancies) there were 16 fetal losses within the 28th week; ten of these occurred in the 2 weeks following the procedure. There were 475 live-births, of which 447 were term deliveries and the other 28 deliveries occurred before the 37th week of gestation.     

Direct evidence of trophic interactions among apex predators in the Late Triassic of western North America

Hypotheses of feeding behaviors and community structure are testable with rare direct evidence of trophic interactions in the fossil record (e.g., bite marks). We present evidence of four predation, scavenging, and/or interspecific fighting events involving two large paracrocodylomorphs (=‘rauisuchians’) from the Upper Triassic Chinle Formation (～220–210 Ma). The larger femur preserves a rare history of interactions with multiple actors prior to and after death of this ～8–9-m individual. A large embedded tooth crown and punctures, all of which display reaction tissue formed through healing, record evidence of a failed attack on this individual. The second paracrocodylomorph femur exhibits four unhealed bite marks, indicating the animal either did not survive the attack or was scavenged soon after death. The combination of character states observed (e.g., morphology of the embedded tooth, ‘D’-shaped punctures, evidence of bicarination of the marking teeth, spacing of potentially serial marks) indicates that large phytosaurs were actors in both cases. Our analysis of these specimens demonstrates phytosaurs targeted large paracrocodylomorphs in these Late Triassic ecosystems. Previous distinctions between ‘aquatic’ and ‘terrestrial’ Late Triassic trophic structures were overly simplistic and built upon mistaken paleoecological assumptions; we show they were intimately connected at the highest trophic levels. Our data also support that size cannot be the sole factor in determining trophic status. Furthermore, these marks provide an opportunity to start exploring the seemingly unbalanced terrestrial ecosystems from the Late Triassic of North America, in which large carnivores far outnumber herbivores in terms of both abundance and diversity.     

A novel test for evaluating horses’ spontaneous visual attention is predictive of attention in operant learning tasks

Attention is described as the ability to process selectively one aspect of the environment over others. In this study, we characterized horses’ spontaneous attention by designing a novel visual attention test (VAT) that is easy to apply in the animal’s home environment. The test was repeated over three consecutive days and repeated again 6 months later in order to assess inter-individual variations and intra-individual stability. Different patterns of attention have been revealed: ‘overall’ attention when the horse merely gazed at the stimulus and ‘fixed’ attention characterized by fixity and orientation of at least the visual and auditory organs towards the stimulus. The individual attention characteristics remained consistent over time (after 6 months, Spearman correlation test, P < 0.05). The validity of this novel test as a predictor of individual attentional skills was assessed by comparing the results, for the same horses, with those obtained in both a ‘classical’ experimental attention test the ‘five-choice serial reaction time task’ (5-CSRTT) and a work situation (lunge working context). Our results revealed that (i) individual variations remained consistent across tests and (ii) the VAT attention measures were not only predictive of attentional skills but also of learning abilities. Differences appeared however between the first day of testing and the following test days: attention structure on the second day was predictive of learning abilities, attention performances in the 5-CSRRT and at work. The VAT appears as a promising easy-to-use tool to assess animals’ attention characteristics and the impact of different factors of variation on attention.     

On properties of linear programming model for acid rain abatement

For linear programming problems arising in the field of acid rain abatement (in the case of a linear source-receptor relationship and linear or piecewise-linear abatement cost functions) the following properties are established.In the optimal solution, the number of sources which are not at an ‘inflection point’ of the corresponding piecewise-linear cost function is equal to the number of binding environmental constraints. (Here ‘inflection point’ denotes a point where the piecewise-linear cost function changes its slope; an environmental constrainst is called ‘binding’ if, for the optimal solution, the calculated deposition is just equal to, and not less than, the constraint.) As a consequences, several (i.e. the remaining) sources have optimum emissions which ‘get stuck’ at an inflection point. This influences the results of sensitivity analyses as well as the numerical accuracy of the optimal solution (if the piecewise-linear cost function has been obtained as a coarse approximation to a more complicated cost function).Moreover, for targets becoming more stringent, the optimum abatement costs may decrease for certain sources, although the total abatement costs increase, of course. This rather unexpected effect indicates that ‘pure’ optimization results should be applied, e.g. in negotiations, in a careful manner.     

中国工业碳减排潜力与路径研究

基于我国工业35个行业2000~2015年的碳排放数据,以Super-SBM模型进行碳排放效率测算,结合劳均碳排放量及劳均工业总产值构造碳排放公平指数,并基于马尔科夫链模型测算碳排放公平及碳排放效率的俱乐部趋同指数,在公平效率协调的视角构造碳减排潜力指数并对35个行业进行碳减排潜力测算,并基于公平-效率二维矩阵图以动态的视角设计我国工业碳减排路径.结果表明：我国工业碳排放公平及碳排放效率均存在较为严重的固化现象,且碳排放效率的固化程度更高,可见我国工业碳减排的效率原则更重要,国家应从效率上挖掘更多的减排潜力;在公平与效率协调视角下测算出来各行业的碳减排潜力较之公平效率相等原则下有所变化,我国工业仍存在较大的碳减排空间;我国工业大部分行业处于"低排放效率、低排放公平"的状态.因此国家应从碳排放效率提升的角度重点扶持"低排放效率、低排放公平"水平类型行业.     

Quantifying the effect of buffer zones,crop areas and spatial aggregation on the externalities of genetically modified crops at landscape level

The development of genetically modified (GM) crops has led the European Union (EU) to put forward the concept of ‘coexistence’ to give farmers the freedom to plant both conventional and GM varieties. Should a premium for non-GM varieties emerge in the market, ‘contamination’ by GM pollen would generate a negative externality to conventional growers. It is therefore important to assess the effect of different ‘policy variables’ on the magnitude of the externality to identify suitable policies to manage coexistence. In this paper, taking GM herbicide tolerant oilseed rape as a model crop, we start from the model developed in Ceddia et al. [Ceddia, M.G., Bartlett, M., Perrings, C., 2007. Landscape gene flow, coexistence and threshold effect: the case of genetically modified herbicide tolerant oilseed rape (Brassica napus). Ecol. Modell. 205, pp. 169–180] use a Monte Carlo experiment to generate data and then estimate the effect of the number of GM and conventional fields, width of buffer areas and the degree of spatial aggregation (i.e. the ‘policy variables’) on the magnitude of the externality at the landscape level. To represent realistic conditions in agricultural production, we assume that detection of GM material in conventional produce might occur at the field level (no grain mixing occurs) or at the silos level (where grain mixing from different fields in the landscape occurs). In the former case, the magnitude of the externality will depend on the number of conventional fields with average transgenic presence above a certain threshold. In the latter case, the magnitude of the externality will depend on whether the average transgenic presence across all conventional fields exceeds the threshold. In order to quantify the effect of the relevant ‘policy variables’, we compute the marginal effects and the elasticities. Our results show that when relying on marginal effects to assess the impact of the different ‘policy variables’, spatial aggregation is far more important when transgenic material is detected at field level, corroborating previous research. However, when elasticity is used, the effectiveness of spatial aggregation in reducing the externality is almost identical whether detection occurs at field level or at silos level. Our results show also that the area planted with GM is the most important ‘policy variable’ in affecting the externality to conventional growers and that buffer areas on conventional fields are more effective than those on GM fields. The implications of the results for the coexistence policies in the EU are discussed.     

“煤改气”投资对宏观经济的拉动效应:基于北京市可计算一般均衡模型分析

“煤改气”是我国大气污染防治行动计划的政策措施之一,国内外目前对“煤改气”政策实施的环境效果研究较多,但对“煤改气”投资对宏观经济的拉动作用研究较少. 为综合评价“煤改气”政策的整体效果、探讨“煤改气”投资对宏观经济的拉动作用,以北京市为例,构建了北京市可计算一般均衡模型(MRDR-BJ),基于2017年北京市投入产出表,模拟不同情景下“煤改气”投资对宏观经济的拉动效应. 结果表明:随着“煤改气”投资的增加,北京市宏观经济增加值、温室气体排放量、就业量、家庭收入均增加;“煤改气”投资每增加20%,这些宏观指标分别增长0.05%、0.07%、0.07%和0.07%;“煤改气”投资对宏观经济的拉动系数为1.77. 研究显示,“煤改气”投资对宏观经济具有较大的拉动效应,建议全国各地尽快落实“煤改气”规划,以加快大气污染治理、促进生态环境建设,助力我国碳达峰、碳中和中长期目标的实现.