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11.
Developing fresh water supply strategies for the long term needs to take into account the fact that the future is deeply uncertain. Not only the extent of climate change and the extent and nature of its impacts are unknown, also socio-economic conditions may change in unpredictable ways, as well as social preferences. Often, it is not possible to find solid ground for estimating probabilities for the relevant range of imaginable possible future developments. Yet, some of these may have profound impacts and consequences for society which could be reduced by timely proactive adaptation. In response to these and similar challenges, various approaches, methods and techniques have been proposed and are being developed to specifically address long-term strategy development under so-called deep uncertainty. This paper, first, offers a brief overview of developments in the field of planning under (deep) uncertainty. Next, we illustrate application of three different approaches to fresh water provision planning under uncertainty in case studies in the Netherlands: a resilience approach, oriented to (re) designing fresh water systems in such a way that they will be less vulnerable, resp. will be able to recover easily from future disturbances; a robustness approach, oriented to quantitative assessment of system performance for various system configurations (adaptation options) under a range of external disturbances, and an exploratory modeling approach, developed to explore policy effectiveness and system operation under a very wide set of assumptions about future conditions.  相似文献   
12.
Motorcyclists have a relative high risk of crash involvement. As a consequence there is an on-going search for safety measures to improve road safety for motorcyclists. One popular measure is motorcycle training. Although intuitively sound, there are only few thorough studies on rider training courses and they do not always show a positive safety effect.  相似文献   
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Tracing tools to resolve neural circuits   总被引:2,自引:0,他引:2  
In this paper we summarize neuroanatomical tracing methods, in particular combinations of methods designed to achieve the combined goals of tracing connectivity and extracting extra information from the projection or the target neurons. These combinations include techniques that identify projection fibres together with the neurons from which they originate, methods which establish the morphological or chemical identity of the target neurons and techniques to verify the presence of contacts between the terminal boutons on fibres and prospective target neurons. In the second part of this paper we describe a method recently developed in our laboratory, which consists of fluorescence tracing (introducing marker #1) combined with immunofluorescence with different fluorochromes (markers #2 and #3). This method enables us to observe the distribution of terminals of a particular set of projection fibres in contact with neurons belonging to two chemically different populations of interneuron. Multifluorescence confocal laser scanning is used for image acquisition of fibres and processes of presumed target neurons, and follow-up is by three-dimensional computer reconstruction. These reconstructions are used to determine that the contacts between the differentially labelled structures are real, i.e. with no optically empty space in between regardless of the angle of inspection. The specific experiments reported in this paper comprise the tracing with biotinylated dextran amine of fibres in the rat brain running from the presubiculum to layer III of the medial division of the entorhinal cortex. We studied the possibility of contacts in the latter area between the terminal boutons of these projecting fibres in association with presumed target neurons, i.e. parvalbumin and calretinin expressing interneurons.  相似文献   
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In most western countries, the participation of females in ICT professional careers is not only low but is also still falling [Anderson, N., Lankhear, C., Timms, C., & Courtney, L. (in press). Because it’s boring, irrelevant and I don’t like computers’: Why high school girls avoid professionally-oriented ICT subjects. Computers & Education.]. Policy makers as well as researchers often assume that the interest of girls in computing and ICT-professions could be increased at school. For example, female teachers who are confident ICT-users, are expected to act as positive role models for girls. However, because most of the research on gender and computing has been focussing on the influence of none-school related factors, there is little empirical evidence that schools or teachers are able to influence girls’ attitude toward ICT. Using the data of a Dutch large-scale survey on ICT use in primary education (almost 4000 grade 5 students), this study explores the influence of both none-school related factors and school related factors on students’ computer attitude. Although the between-school variance of girls’ computer attitude is higher than that of boys’ computer attitude, multilevel analyses show that most of the variance in computer attitude is explained by none-school related student factors. Two school related factors turned out to have a small positive effect on the computer attitude of girls: a teacher-centred pedagogical approach and the computer experience of female teachers.  相似文献   
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Tyr52 and Tyr73 are conserved amino acid residues throughoutall vertebrate phospholipases A2. They are part of an extendedhydrogen bonding system that links the N-terminal -NH+3 -groupto the catalytic residues His48 and Asp99. These tyrosines werereplaced by phenylalanines in a porcine pancreatic phospholipaseA2 mutant, in which residues 62–66 had been deleted (62–66PLA2).The mutations did not affect the catalytic properties of theenzyme, nor the folding kinetics. The stability against denaturatlonby guanidine hydrochloride was decreased, however. To analysehow the enzyme compensates for the loss of the tyrosine hydroxylgroup, the X-ray structures of the Y52F and AY73F mutants weredetermined. After crystallographic refinement the final crystallographicR-factors were 18.1% for the %Y52F mutant (data between 7 and2.3 Å resolution) and 19.1% for the Y73F mutant (databetween 7 and 2.4 Å resolution). No conformational changesoccurred in the mutants compared with the 62–66PLA2, butan empty cavity formed at the site of the hydroxyl group ofthe former tyrosine. In both mutants the Asp99 side chain losesone of its hydrogen bonds and this might explain the observeddestabilization.  相似文献   
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Standard psycholexical studies of personality structure have produced a similar 6-factor solution in 7 languages (Dutch, French, German, Hungarian, Italian, Korean, Polish). The authors report the content of these personality dimensions and interpret them as follows: (a) a variant of Extraversion, defined by sociability and liveliness (though not by bravery and toughness); (b) a variant of Agreeableness, defined by gentleness, patience, and agreeableness (but also including anger and ill temper at its negative pole); (c) Conscientiousness (emphasizing organization and discipline rather than moral conscience); (d) Emotionality (containing anxiety, vulnerability, sentimentality, lack of bravery, and lack of toughness, but not anger or ill temper); (e) Honesty-Humility; (f) Intellect/Imagination/Unconventionality. A potential reorganization of the Big Five factor structure is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
19.
The best way of organizing creativity within organizations remains somewhat enigmatic to scholars, particularly when it comes to the role of constraints. On the one hand, creative organizations are often associated with freedom, autonomy, weak rules and few boundaries. On the other hand, several studies suggest that constraints, particularly design constraints, often stimulate creativity rather than suppress it. All in all, findings are mixed and inconclusive, and further research that explores this area of tension is required. The goal of this paper is twofold. Firstly, we introduce the topic of constraints and creativity, and raise some of the open questions in this field. By way of illustration, we report on a preliminary study about the role of constraints. Secondly, we set the stage for the contributions in this special issue on creativity and innovation under constraints, by identifying four central themes for further research. We subsequently outline the articles in this issue, and show how each of them contributes to one or more of these themes.  相似文献   
20.
The proximity framework serves to analyse and understand how collaborations form and develop over time, and how these affect innovation and learning. The framework has inspired and informed empirical studies in several contexts, contributing to our understanding of the dynamics of dyadic collaborations, industrial clusters and districts, and regional innovation systems, to name but a few. Recent conceptual and empirical advances have called attention to the role of personal proximity and social proximity in such collaborations. In addition to other forms of proximity, these two dimensions could make up the glue that holds knowledge networks together. In the introduction to this special issue, we elaborate upon this proposition, setting out a point-of-departure for the three empirical studies collected in this issue. We summarize the findings of these papers, and develop a research agenda from those findings that may guide proximity researchers to novel research problems and useful research designs.  相似文献   
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