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101.
私营企业主是我国迅速兴起和发展的一个群体.本文运用马克思主义的阶级和阶层分析方法,以温州私营企业主的特征为实证分析个案,从私营企业主的所有权性质、劳动和收入的特点、与雇工的关系以及私营企业主与社会主义社会的联系等角度对私营企业主的社会属性进行研究. 相似文献
102.
Kathryn S. McCarthy Micah Watanabe Jianmin Dai Danielle S. McNamara 《Journal of Research on Technology in Education》2020,52(3):301-321
AbstractComputer-based learning environments (CBLEs) provide unprecedented opportunities for personalized learning at scale. One such system, iSTART (Interactive Strategy Training for Active Reading and Thinking) is an adaptive, game-based tutoring system for reading comprehension. This paper describes how efforts to increase personalized learning have improved the system. It also provides results of a recent implementation of an adaptive logic that increases or decreases text difficulty based on students’ performance rather than presenting texts randomly. High school students who received adaptive text selection showed increased sense of learning. Adaptive text selection also resulted in greater pre-training to post-training comprehension test gains, especially for less-skilled readers. The findings demonstrate that system-driven, just-in-time support consistent with the goals of personalized learning benefit the efficacy of computer-based learning environments. 相似文献
103.
采用X射线荧光光谱仪对体表为古铜色并有金属光泽的短跗星花金龟进行了体表(背、腹面)无损多元素定性检测。样品灰化后,对其灰又进行了多元素定性检测。结果发现,此种金龟子体表所呈现的金属光泽与虫体含有较多的Cu、Zn有关。 相似文献
104.
This paper discusses the INAA results of REE in clays atand near some Permian/Triassic boundaries of South China.It showsthat the REE patterns of boundary clays differ from those of non-boundary clays.One difference is that the boundary clays are moreenriched in LREE,with steeper slope of REE and a smaller Eu nega-tive anomaly than the non-boundary clays.Another difference is that theboundary clays show a small Ce negative anomaly,but no Ce anomalyoccurs in the non-boundary clays.From these REE patterns and some other experimental facts,it isproposed that the P/T boundary clay may be a mixed product consistingof the acidic-intermediate ash and the upper crust substance representingsputtering component,and the calculated fraction of the former andlatter is 7/3. 相似文献
105.
本文通过对高速公路某连拱隧道的工程地质分析,综合运用隧道地质超前预报及监控量测的手段,详细分析了隧道支护体系在设计上的合理性以及在施工上是否得到了合理的保证。通过对掌予面的地质描述发现前方围岩可能出现的问题做出及时准确的预报。 相似文献
106.
107.
智力资本度量的记分卡方法评述 总被引:11,自引:0,他引:11
知识经济时代,企业的价值关键在于其拥有的智力资本,对智力资本实施有效的管理对于企业建立持久的竞争优势至关重要。但智力资本的管理离不开对智力资本的度量,只有明确企业现有智力资本存量的基础上,才可能真正地对智力资本实施有效的管理。本文简单介绍了一类智力资本度量方法——记分卡方法中各个模型的基本思路和使用方法。 相似文献
108.
Leaf senescence is often caused by water deficit and the chimeric gene PSA612-1PT is an auto-regulated gene delaying leaf senescence. Using in vitro leaf discs culture system, the changes of contents of chlorophylls, carotenoids, soluble protein and thiobarbituric acid reactive substance (TBARS) and antioxidant enzymes activities were investigated during leaf senescence of PSA612-1PT modified gerbera induced by osmotic stress compared with the control plant (wild type). Leaf discs were incubated in 20%, 40% (w/v) polyethylene glycol (PEG) 6 000 nutrient solution for 20 h under continuous light [ 130 μmol/(m^2·s)]. The results showed that the contents of chlorophylls, carotenoids and soluble protein were decreased by osmotic stress with the decrease being more pronounced at 40% PEG, but that, at the same PEG concentration the decrease in the transgenic plants was significantly lower than that in the control plant. The activities of superoxide dismutase (SOD), catalases (CAT), ascorbate peroxidase (APX), guaiacol peroxidase (GPX) and dehydroascorbate reductase (DHAR) were stimulated by PEG treatment. However, the increases were higher in PSA612-IPT transgenic plants than in the control plants, particularly at 40% PEG treatment. Lipid peroxidation (TBARS content) was increased by PEG treatment with the increase being much lower in transgenic plant than in the control plant. It could be concluded that the increases in the activities ofantioxidant enzymes including SOD, CAT, APX, GPX and DHAR were responsible for the delay of leaf senescence induced by osmotic stress. 相似文献
109.
Relationship between hyperuricemia and metabolic syndrome 总被引:6,自引:0,他引:6
Chen LY Zhu WH Chen ZW Dai HL Ren JJ Chen JH Chen LQ Fang LZ 《Journal of Zhejiang University. Science. B》2007,8(8):593-598
Objective: To investigate the relationship between metabolic syndrome and hyperuricemia. Methods: A total of 2 374 subjects who received health examination in our hospital from Jan. 2004 to Dec. 2006 were enrolled in our study. Hyperuricemia is defined as ≥7 mg/dl (in men) or ≥6.0 mg/dl (in women). Metabolic syndrome was defined using AHA/NHLBI (American Heart Association/National Heart, Lung, and Blood Institute) criteria. Results: (1) The overall prevalence of hyperuricemia was 13.10%. The condition was more common in men than in women (19.07% vs 3.42%). (2) Among men, uric acid concentration is statistically significantly positively correlated with waist circumference, blood pressure, and triglyceride. Uric acid is negatively correlated with serum high-density lipoprotein-cholesterol (HDL-C). Uric acid concentration is most strongly correlated with serum triglyceride (r=0.379) and waist circumference (r=0.297). Among women, statistically significant positive correlations were noted for the serum uric acid concentrations with waist circumference, triglyceride and fasting plasma glucose. Serum triglyceride (r=0.329) and waist circumference (r=0.234) are most strongly correlated with uric acid concentrations. (3) Men with hyperuricemia had a 1.634-fold increased risk of metabolic syndrome as compared with those without hyperuricemia odds ratio (OR)=1.634, P=0.000. Women with hyperuricemia had a 1.626-fold increased risk of metabolic syndrome (OR=1.626, P=0.000) as compared with those without hyperuricemia. Conclusion: Hyperuricemia is prevalent among Chinese population. Additionally, serum uric acid is positively associated with metabolic syndrome. 相似文献
110.
[目的 /意义]对在线社区用户承诺影响因素的相关实证研究进行梳理和再分析,以解释影响在线社区用户承诺的一般性因素,为后续研究提供参考。[方法 /过程]运用元分析方法,选取以用户承诺为研究主题、以在线社区为研究情境的文献作为样本文献,归纳和识别在线社区的用户承诺影响因素,并进一步探索影响异质性的调节变量。[结果 /结论 ]显著影响在线社区用户承诺的因素包括系统外部、需求动机及用户感知三个类别的10个变量,与在线社区用户承诺为中度相关关系的有情感依恋、信息性动机、感知娱乐性、信息质量,而社交动机、社会互动、满意度、信任、感知收益、社区认同与用户承诺高度相关。在线社区类型会对情感依恋、社会互动、感知娱乐性等变量与用户承诺之间的关系产生调节。研究结果对未来深入研究和不同情境研究具有借鉴意义,也对在线社区运营具有实践指导作用。 相似文献