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991.
992.
旨在探索一种新的采购管理模式,帮助企业降低采购成本,提高采购效率。通过构建以EVA为指导的采购流程,重点讨论与采购人员、供应商相关的核心环节,提出了完善采购人员管理体系、健全供应商管理机制等方面的策略,以实现“采购使企业增值”的目的。 相似文献
993.
我国高校的行政化管理模式由来已久,随着现代高等教育体制与教学制度的不断完善,高校行政化收到了越来越多的非议,并逐步演变成为教育体制改革的焦点。通过对高校“行政化”弊端的分析,认真反思如何使高效发展走出“行政化”制约,如何归还高校办学的独立自主权利。由此可见,废除高校行政级别、剥离教育部对高校的管理和评价权、排除行政干预对学术活动带来影响等呼声日益高涨,逐步演变成为“去行政化”改革的重要手段。 相似文献
994.
995.
Dimov N Muñoz L Carot-Sans G Verhoeven ML Bula WP Kocer G Guerrero A Gardeniers HJ 《Biomicrofluidics》2011,5(3):34102-3410212
To prepare a biosynthetic module in an infochemical communication project, we designed a silicon/glass microreactor with anti-adsorption polyelectrolyte multilayer coating and immobilized alcohol acetyl transferase (atf), one of the key biosynthetic enzymes of the pheromone of Spodoptera littoralis, on agarose beads inside. The system reproduces the last step of the biosynthesis in which the precursor diene alcohol (Z,E)-9,11-tetradecadienol is transformed into the major component (Z,E)-9,11-tetradecadienyl acetate. The scope of this study was to analyze and implement a multilayer, anti-adsorption coating based on layer-by-layer deposition of polyethylenimine/dextransulfate sodium salt (PEI/DSS). The multilayers were composed of two PEI with molecular weights 750 and 1.2 kDa at pH 9.2 or 6.0. Growth, morphology, and stability of the layers were analyzed by ellipsometry and atomic force microscopy (AFM). The anti-adsorption functionality of the multilayer inside the microreactor was validated. The activity of His(6)-(atf) was measured by gas chromatography coupled to mass spectrometer (GC-MS). 相似文献
996.
Edwards TL Harper JC Polsky R Lopez DM Wheeler DR Allen AC Brozik SM 《Biomicrofluidics》2011,5(4):44115-4411514
Herein is described the fabrication and use of a plastic multilayer 3-channel microfluidic fixture. Multilayer devices were produced by laser machining of plastic polymethylmethacrylate and polyethyleneterapthalate laminates by ablation. The fixture consisted of an array of nine individually addressable gold or gold/ITO working electrodes, and a resistive platinum heating element. Laser machining of both the fluidic pathways in the plastic laminates, and the stencil masks used for thermal evaporation to form electrode regions on the plastic laminates, enabled rapid and inexpensive implementation of design changes. Electrochemiluminescence reactions in the fixture were achieved and monitored through ITO electrodes. Electroaddressable aryl diazonium chemistry was employed to selectively pattern gold electrodes for electrochemical multianalyte DNA detection from double stranded DNA (dsDNA) samples. Electrochemical detection of dsDNA was achieved by melting of dsDNA molecules in solution with the integrated heater, allowing detection of DNA sequences specific to breast and colorectal cancers with a non-specific binding control. Following detection, the array surface could be renewed via high temperature (95 °C) stripping using the integrated heating element. This versatile and simple method for prototyping devices shows potential for further development of highly integrated, multi-functional bioanalytical devices. 相似文献
997.
Miller PR Gittard SD Edwards TL Lopez DM Xiao X Wheeler DR Monteiro-Riviere NA Brozik SM Polsky R Narayan RJ 《Biomicrofluidics》2011,5(1):13415
In this study, carbon fiber electrodes were incorporated within a hollow microneedle array, which was fabricated using a digital micromirror device-based stereolithography instrument. Cell proliferation on the acrylate-based polymer used in microneedle fabrication was examined with human dermal fibroblasts and neonatal human epidermal keratinocytes. Studies involving full-thickness cadaveric porcine skin and trypan blue dye demonstrated that the hollow microneedles remained intact after puncturing the outermost layer of cadaveric porcine skin. The carbon fibers underwent chemical modification in order to enable detection of hydrogen peroxide and ascorbic acid; electrochemical measurements were demonstrated using integrated electrode-hollow microneedle devices. 相似文献
998.
Whether immigrants to the U.S. from collectivist cultures will adopt American individualist values is an important question at the intersection of theories on acculturation and individualism/collectivism. According to the assimilation hypothesis, Turkish immigrants to the U.S. should become more individualistic with increasing length of stay. Alternatively, the immigrant interdependence hypothesis proposes that the exigencies of immigration require retaining or increasing collectivist values and behaviors, especially the willingness to rely on others. Measures of individualism and collectivism were obtained from Turkish immigrants to the U.S., Turks residing in Istanbul, and residents of Boston. Bostonians and Istanbul residents differed primarily on vertical collectivism, which is the tendency to subordinate ones own goals to those of in-group authority figures. Immigrants’ values did not change with increasing length of stay in the U.S., refuting the assimilation hypothesis. When immigrants were compared to non-immigrants, immigrants endorsed stronger horizontal and vertical collectivism and more desire to both give and receive, consistent with the immigrant interdependence hypothesis. However, this hypothesis was not uniformly supported. Compared to non-immigrants, immigrants reported more self-reliance with competition, and more internal locus of control, indicating a sense of agency and responsibility. Findings are consistent with the view that immigrants adjust in complex ways to their new society, and may have different temperaments than non-immigrants. 相似文献
999.
The purposes of this study were to associate age-related performance deficits in children with the use of recall strategies and to determine whether children who performed poorly in cycling would benefit from learning a recall strategy. In Experiment 1, 18 younger children (ages 5-7years) and 18 older children (ages 8-10 years) were asked to recall selected pedaling cadences. The majority of the older children used strategies and performed with less error than the younger children. In Experiment 2, children with a high number of errors in Experiment 1 were assigned to an experimental or a control group. The children in the experimental group were taught to use a specific recall strategy. The results showed that children who received the instruction in strategy use improved their performance. 相似文献
1000.
Much research has examined shoulder range of motion adaptations in overhead-unilateral athletes. Based on the void examining overhead-bilateral athletes, especially competitive swimmers, we examined shoulder external rotation, isolated internal rotation, composite internal rotation, and total arc of motion range of motion of competitive swimmers. The range of motion of registered competitive swimmers (n = 144, age = 12-61 years) was compared by limb (dominant, non-dominant), sex, and age group (youth, high school, college, masters). Significantly (P < 0.05) greater dominant external rotation was observed for both men and women high school and college swimmers, youth women swimmers, and men masters swimmers compared with the non-dominant limb. The isolated internal rotation (glenohumeral rotation), composite internal rotation (glenohumeral rotation plus scapulothoracic protraction), and total arc of motion (external rotation plus composite internal rotation) of the non-dominant limb was significantly greater than that of the dominant limb by sex and age group. Youth and high school swimmers demonstrated significantly greater composite internal rotation than college and masters swimmers. Youth swimmers displayed significantly greater total arc of motion than all other age groups. These data will aid in the interpretation of shoulder range of motion values in competitive swimmers during preseason screenings, injury evaluations and post-rehabilitation programmes, with the results suggesting that differences exist in bilateral external rotation, isolated internal rotation, composite internal rotation, and total arc of motion range of motion. 相似文献