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171.
Riverine inputs are a major source of nutrients to the Laurentian Great Lakes and have important effects on nearshore biological processes, where mixing between river and lake water leads to formation of heterogeneous river plumes. We examined the physical and chemical characteristics of the St. Joseph River plume in southern Lake Michigan between May and October 2011, and in October 2012, June 2013 and April 2014. Specific electric conductivity and stable isotopes of water were used to quantify the fraction of river water (FRW) at sampling sites in Lake Michigan. Both tracers predicted similar patterns of FRW among sites; however, there was a systematic offset between the two methods, and specific electric conductivity method under-predicted the FRW by ~5%. We observed a distinct, seasonally varying river plume, with plume size correlated with flow rate of St. Joseph River. Within the plume, sediments and nutrients were non-conservative and exhibited significant and seasonally varying losses that we attribute to settling of particle-bound nutrients and/or nutrients in particulate phase below the plume. The characteristics and the spatiotemporal heterogeneity of the river plume documented here may have important implications for the nearshore biogeochemistry of the Great Lakes and for understanding the roles of these features in ecological processes in nearshore areas.  相似文献   
172.
This paper examines the role of ergonomics in product and systems design. Market requirements as well as legislation have increased the use of ergonomics in design. This has increased the demands upon both ergonomists and designers. The ergonomist must learn to participate in the product development team. In return the design team must find the time and resources necessary for the inclusion of ergonomics in the development programme. This paper discusses the different roles played by the ergonomist in each stage of product and systems design. The need to give designers, engineers and management a fundamental education in ergonomics is highlighted as is the need for the ergonomist to consider the financial consequences of his work.  相似文献   
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One of the most important determinants for the design of the future energy system is whether or not constraints on CO2 emissions will be imposed. Here, this issue is treated as a decision under uncertainty. Three strategies have been considered: immediate action to adapt to a future emission constraint (Commitment), business as usual (No Hedging), and hedging (Hedging). In the case of hedging, preparations are made outside the energy system, but the energy system itself is allowed to develop according to baseline assumptions until the uncertainty has been resolved. The IEA-MARKAL model has been used to show how efficient and robust the three strategies are under different developments. The development of the Swedish energy system has been studied for two rates of economic growth in combination with three nuclear policies and two CO2 policies. The value of preparations for meeting a possible restriction on CO2 emissions, i.e., following either the Commitment or the Hedging strategy, is considerably higher when the energy demand increases rapidly. In the low growth case, the choice of strategy is largely dependent upon the decision maker's estimate of the likelihood of an emission cap. In the high growth case, this likelihood must be considered to be very small in order to choose the No Hedging strategy, even with reinvestments in nuclear capacity beyond 2010.  相似文献   
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A synthetic IgG-binding domain based on staphylococcal protein A   总被引:5,自引:0,他引:5  
A synthetic IgG-binding domain based on staphylococcal proteinA was designed with the aid of sequence comparisons and computergraphic analysis. A strategy, utilizing non-palindromic restrictionsites, was used to overcome the difficulties of introducingshe-specific changes into the repetitive gene. A single mutagenizedgene fragment was polymerized to different multiplicities, andthe different gene products were expressed in Escherichia coli.Using this scheme, protein A-like proteins composed of differentnumbers of IgG-binding domains were produced. These domainswere changed to lack asparagine-glycine dipeptide sequencesas well as methionine residues and are thus, in contrast tonative protein A, resistant to treatment with hydroxylamineand cyanogen bromide.  相似文献   
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This paper reports on the innovative, now defunct, Volvo Uddevalla final assembly plant. Theoretical frames of reference, the design process and empirical data on work group characteristics and working conditions are focused upon.

Information regarding the Uddevalla plant has been gathered during a long-term co-operation project with the Volvo Corporation. During the closing-down period we obtained full access to all the production engineering data and personnel files available. We also had the opportunity of studying the responses to a questionnaire distributed to a random sample of blue-collar workers.

Working conditions in Uddevalla in the form of psychosocial job factors are compared with industrial blue-collar workers in general as well as with assembly workers in the closed down Volvo Kalmar final assembly plant, which had a different, more traditional, production system. The paper also compares the psychosocial job factors, performance measures and work-group characteristics in the five assembly workshops in the Uddevalla plant.

In comparing assembly workshops, the paper contrasts two approaches to competence development and work structuring used in Uddevalla, namely (1) giving priority to individual in-depth training of a specific task or (2) giving priority to a large competence overlap between individuals in a work group.

Relevance to industry

This paper reports and explains some results from a multidisciplinary evaluation of shop-floor work in the Volvo Uddevalla plant, a full-scale assembly plant with parallellized flow and long cycle time, using autonomous work groups. These experiences should be of general interest to industries searching for the factory of the future.  相似文献   

180.
This article conceptualizes the construct of the intelligent personality as an indicator of intellectual competence in an attempt to expand the traditional concept of intelligence and account for both ability and nonability determinants of academic performance. Theoretical implications are discussed with regard to recent attempts to (a) explain correlations between personality and intelligence measures, (b) conceptualize novel constructs that may bridge the gap between intelligence and personality, and (c) develop a conceptual model for understanding the relationship among individual differences underlying human performance in real-world settings. Practical implications are also considered, in particular with regard to the validity of the intelligent personality as a predictor of future achievement. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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