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71.
This article discusses the influence of future changes in the demographics of working populations and the characteristics of the workplace on research, development, and policy for training systems. Analyses of these changes indicate that there will be more expectations that training programs will serve as a positive hope to maximize the potential of each person. This will result in increased emphasis on research to identify abilities required to perform more cognitively complex jobs. Also, research on basic skill and support programs to permit unskilled youth to enter the world of work will be required. In addition, there will be a need for research on training necessary to help future managers and leaders work with members of a more diverse work force. Finally, the implications of these changes suggest that we need policies that consider research and development on retraining as a national need to help all individuals maximize their individual talents. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
72.
The effects of growth temperature and salinity on the cellular fatty acids were investigated on Aeromonas caviae, Aeromonas hydrophila and Aeromonas sobria. Under optimal growth conditions, fatty acids patterns were dominated by even-numbered chains C(16:0), C(16:1cis9), C(18:1cis11), C(12:0) and C(14:0). Growth temperature modifications induced, in the three Aeromonas species, important changes in fatty acid (i) unsaturation, (ii) branching and (iii) chain length. An important decrease in the C(18:1cis11) fatty acid content was observed for the three species below 15 degrees C and above 25 degrees C. The evolution of C(18:1cis11) and C(16:0) showed a mirror image for the three Aeromonas species. Low NaCl concentrations did not elicit significant changes in the fatty acids content of the three Aeromonas species. However, for high NaCl concentration in the medium, the growth ability was related to an important decrease of the unsaturated to saturated fatty acids ratio indicating a membrane rigidification. Thermal and salinity adaptations were branched fatty acid-dependent for A. caviae, whereas this phenomenon was less significant for A. hydrophila and A. sobria.  相似文献   
73.
The areal energy density of on‐chip micro‐supercapacitors should be improved in order to obtain autonomous smart miniaturized sensors. To reach this goal, high surface capacitance electrode (>100 mF cm?2) has to be produced while keeping low the footprint area. For carbide‐derived carbon (CDC) micro‐supercapacitors, the properties of the metal carbide precursor have to be fine‐tuned to fabricate thick electrodes. The ad‐atoms diffusion process and atomic peening effect occurring during the titanium carbide sputtering process are shown to be the key parameters to produce low stress, highly conductive, and thick TiC films. The sputtered TiC at 10?3 mbar exhibits a high stress level, limiting the thickness of the TiC‐CDC electrode to 1.5 µm with an areal capacitance that is less than 55 mF cm?2 in aqueous electrolyte. The pressure increase up to 10?2 mbar induces a clear reduction of the stress level while the layer thickness increases without any degradation of the TiC electronic conductivity. The volumetric capacitance of the TiC‐CDC electrodes is equal to 350 F cm?3 regardless of the level of pressure. High values of areal capacitance (>100 mF cm?2) are achieved, whereas the TiC layer is relatively thick, which paves the way toward high‐performance micro‐supercapacitors.  相似文献   
74.
The repair, the reinforcement as well as the setting in safety of buildings and existing reinforced and/or pre-stressed concrete structure is a real technological stake and a socio-economic problem for the near future. The introduction of composites in civil engineering is an interesting answer to these goals, but they brought an important amount of new problems that have to be solved for safe structural applications under combined mechanical and environmental loadings. In fact during the past five years, we have witnessed exponential growth in research or field demonstrations of fiber-reinforced composites in civil engineering. Manufacturers and designers have now access to a wide range of composite materials. However, they face great problems with forecasting the reliability of composite materials. Their introduction in civil engineering applications is a difficult operation due to working environment and weathering conditions. The objective of this paper is to study the effect of these conditions and their consequences on the mechanical properties of the final composite. An analysis of the rheological (viscoelastic) properties was carried out in order to observe the glass transition temperature evolution according to reactive mixture stoichiometry and weathering conditions.  相似文献   
75.
The acylation reaction of 2-butylbenzofuran withp-anisoyl chloride andp-anisic acid in the presence of faujasite type zeolites, in the liquid phase, is reported. A good initial selectivity to the 3-acylated derivative is obtained, but the selectivity decreases with time. This result is explained by the involvement of a deacylation-reacylation process.  相似文献   
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77.
This paper presents a new composite heuristics approach for solving the N-product, M-stage lot sizing and scheduling problem with dynamic demands and limited production capacity. The first phase of these composite heuristics aims at finding a feasible solution. This solution is such that for each period and for each product, the lot size equals the net demand of the considered period plus the demand of a number of upcoming periods. If capacity does not satisfy all demands of a given period, we try to find earlier periods where we can produce the missing units. The second phase is an improvement procedure which recursively attempts to move back each lot, provided that it is both more economical to do so and capacity feasible. We also provide two variants of this heuristic to handle the case where production capacity can be increased by using overtime. Overtime is a usual practice in real life which, in many cases, allows a reduction of the overall cost. The first variant constructs the initial solution without recourse to overtime and introduces overtime only during the solution improvement phase. The second one considers overtime during both the first and second phases. The performance of the proposed heuristics is numerically assessed and the most efficient ones are identified.  相似文献   
78.
Much research has been dedicated to understanding the molecular basis of UV damage to biomolecules, yet many questions remain regarding the specific pathways involved. Here we describe a genome-mediated mechanism that causes site-specific virus protein cleavage upon UV irradiation. Bacteriophage MS2 was disinfected with 254 nm UV, and protein damage was characterized with ESI- and MALDI-based FT-ICR, Orbitrap, and TOF mass spectroscopy. Top-down mass spectrometry of the products identified the backbone cleavage site as Cys46-Ser47 in the virus capsid protein, a location of viral genome-protein interaction. The presence of viral RNA was essential to inducing backbone cleavage. The similar bacteriophage GA did not exhibit site-specific protein cleavage. Based on the major protein fragments identified by accurate mass analysis, a cleavage mechanism is proposed by radical formation. The mechanism involves initial oxidation of the Cys46 side chain followed by hydrogen atom abstraction from Ser47 C(α). Computational protein QM/MM studies confirmed the initial steps of the radical mechanism. Collectively, this study describes a rare incidence of genome-induced protein cleavage without the addition of sensitizers.  相似文献   
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