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G. A. Alabi 《Information processing & management》1985,21(6):525-533
This paper presents the results of a comparative cost study of the manual circulation system and experimental automated system in a university library in Nigeria. Two sets of data were collected: one on the existing manual circulation system and the other on the experimental automated system on an Apple II microcomputer. Eight different circulation activities were identified for evaluation for which the direct labor cost of circulating a book on each system was calculated. The experimental automated system was found to be less labor intensive than the manual system, although overall unit cost of book circulation on the automated system was higher than on the manual system ($0.59 and $0.49, respectively). Factors attributed to the higher unit cost on the automated system were the cost of equipment and the low circulation figure. However, the automated system was found to be more effective in providing up-to-date and accurate data required for the monitoring of the library stock. 相似文献
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P. Sharma M. Bose Isa Mohd S. Bagdi H. G. Raj 《Indian journal of clinical biochemistry : IJCB》2000,15(2):83-87
Genomic DNA from a clinical isolate ofMycobacterium avium-intracellulare complex was purified and cloned in PBR 322 at the tetracycline resistance site using Bam HI restriction enzyme. A 16 kb cloned
fragment was purified, radiolabeled and used as a probe. Genomic DNA isolated from nineteen MAC strains, threeM. tuberculosis strains and oneM. kansasii strain were digested with Eco RI restriction enzyme, Southern blotted and hybridized with the 16 kb cloned and labeled fragment.
Twelve MAC strains showed positive hybridization although five strains gave faint signals. Positive hybridization was noted
in two out of the threeM. tuberculosis strains, possibly due to shared DNA homology. No signal was received from the singleM. kansasii strain used in this study. 相似文献
67.
本文对秦始皇兵马俑博物馆室内采集的长短期降尘、大气悬浮颗粒物和彩绘漆层进行了SEM-EDX研究,在大气悬浮颗粒、短期和长期降尘中,含硫颗粒的粒径分别为0.9~22.8μm、1.0~29.0μm和1.2~37.7μm,多为石膏与粘土或石英以内部混合的状态存在。降尘中的附着型絮状硫酸钙多于大气悬浮颗粒物中,显示降尘和大气中的二氧化硫发生了累进的化学反应。彩绘漆层表面的坑和裂隙附近观察到原位生长的硫酸钙晶体,显示漆层材料或降尘颗粒物与大气二氧化硫之间的酸化学反应,可能是彩绘漆层表面受侵蚀形成微小坑和裂隙的原因之一。 相似文献
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Tun Aksan Aygl Gndz Blent Yildiz Mehmet Cemal 《International journal for the advancement of counseling》2022,44(1):145-163
International Journal for the Advancement of Counselling - The aim of the study is to examine the mediating role of self-efficacy in the relationship between vicarious trauma (VT) and psychological... 相似文献
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The present research examined the role of maladaptive self-regulatory beliefs as vulnerability factors for academic and emotional difficulties during the transition to middle school. A short-term longitudinal design was employed to follow two groups of early adolescents: 187 adolescents who experienced a school transition between the fifth and sixth grades, and 142 adolescents who did not experience a school transition between the fifth and sixth grades. Adolescents completed measures of perceptions of academic control and importance of academic success, experience of chronic academic strain, daily school hassles, and depressive symptoms. Teachers reported on students' academic engagement, including levels of helpless behavior, effort, and academic performance. Consistent with the proposed model of self-regulation, maladaptive self-regulatory beliefs (i.e., decreased perceptions of academic control and importance) predicted individual differences in perceived school-related stress and depressive symptoms over the course of the middle school transition, but were not associated with academic and emotional difficulties in adolescents who remained in a stable school environment. Moreover, a self-regulatory sequence was identified proceeding from maladaptive self-regulatory beliefs, to academic disengagement, to enhanced perceptions of school-related stress, to depressive symptoms. This study bridges prior theory and research concerning the psychological impact of normative developmental transitions, the developmental context of depression, and the associations among self-regulatory beliefs, achievement-related behavior, and emotional experience. 相似文献
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Mengtian Xia Astrid M. G. Poorthuis Qiang Zhou Sander Thomaes 《Child development》2022,93(2):e207-e221
Western literature suggests that young children overestimate their performance across a range of tasks. Research in non-Western cultures, however, is lacking. In 2019, 101 Chinese (52% girls) and 98 Dutch (49% girls) children, ages 4 and 5, were asked to estimate how well they would perform on both a motor and a memory task. Children from both countries overestimated their performance to the same extent ( = .077 and .027 for the motor and memory tasks, respectively). They generally persevered in doing so despite receiving realistic performance feedback. Yet, children overestimated their peers’ performance about as much as their own performance, in some cases even more. This is the first demonstration of performance overestimation in children growing up in a non-Western culture. 相似文献