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81.
植物生长调节剂对植物的生长发育有重要影响。本实验以模式植物拟南芥菜为材料,调查了外加生长素类和细胞分裂素类生长调节剂对拟南芥菜子叶、下胚轴和根生长的影响,使人们对植物生长调节剂在植物发育调控中的作用,以及在器官发育中的功能和作用的分子机理有更进一步的认识。 相似文献
82.
Maria Patsarika 《Discourse: Studies in the Cultural Politics of Education》2014,35(4):527-539
Current times are witnessing multiple challenges in the economic, political and social domain, which modern citizens and professionals are required to address with an enterprising mindset. Young people have not been left intact by the spirit of new capitalism. In the face of ongoing educational changes on a European level, being a student transcends the boundaries of the school community. Young people thus oscillate between different identities: on the one hand, that of the child who lives in the here and now, and on the other hand, that of the pseudo-adult and in-the-make professional. In this light, the paper explores the new role of the professional student and discusses the implications of a neoliberal student model. It concludes by proposing a more humanistic understanding of the student role, which positions young people in a dynamic learning process and relationship with the world around them. 相似文献
83.
文章基于安徽省1990-2013年的经济增长数据以及工业“三废”的排放量等环境污染指标,建立了向量自回归(VAR)模型。利用脉冲响应分析以及方差分解技术分析方法来研究经济增长与环境污染之间动态作用机制。结果显示：安徽省经济增长主要依赖于产生工业废气和废水的企业;经济增长对环境污染的解释力较强,而环境污染对经济增长的解释力相对较弱;环境污染对经济增长的推动只能在短期起作用,这种发展模式是不可持续的,并且会形成破坏环境的恶性循环;保护环境、惩治污染与经济增长并非是零和博弈,而是可以相互促进的。 相似文献
84.
In recent years, many U.S. states have introduced growth models as part of their educational accountability systems. Although the validity of growth‐based accountability models has been evaluated for the general population, the impact of those models for English language learner (ELL) students, a growing segment of the student population, has not received sufficient attention. We evaluated three commonly used growth models: value tables or transition matrices, projection models, and student growth percentiles (SGP). The value table model identified more ELL students as on track to proficiency, but with lower accuracy for ELL students. The projection and SGP models were more accurate overall, but classified the fewest ELL students as on track and were less likely to identify ELL students who would later be proficient. We found that each model had significant trade‐offs in terms of the decisions made for ELL students. These findings should be replicated in additional state contexts and considered in the development of future growth‐based accountability policies. 相似文献
85.
Sonya K. Sterba 《Structural equation modeling》2013,20(4):630-647
Individual growth trajectories of psychological phenomena are often theorized to be nonlinear. Additionally, individuals’ measurement schedules might be unique. In a structural equation framework, latent growth curve model (LGM) applications typically have either (a) modeled nonlinearity assuming some degree of balance in measurement schedules, or (b) accommodated truly individually varying time points, assuming linear growth. This article describes how to fit 4 popular nonlinear LGMs (polynomial, shape-factor, piecewise, and structured latent curve) with truly individually varying time points, via a definition variable approach. The extension is straightforward for certain nonlinear LGMs (e.g., polynomial and structured latent curve) but in the case of shape-factor LGMs requires a reexpression of the model, and in the case of piecewise LGMs requires introduction of a general framework for imparting piecewise structure, along with tools for its automation. All 4 nonlinear LGMs with individually varying time scores are demonstrated using an empirical example on infant weight, and software syntax is provided. The discussion highlights some advantages of modeling nonlinear growth within structural equation versus multilevel frameworks, when time scores individually vary. 相似文献
86.
Sarah Depaoli 《Structural equation modeling》2013,20(4):534-560
Proper model specification is an issue for researchers, regardless of the estimation framework being utilized. Typically, indexes are used to compare the fit of one model to the fit of an alternate model. These indexes only provide an indication of relative fit and do not necessarily point toward proper model specification. There is a procedure in the Bayesian framework called posterior predictive checking that is designed theoretically to detect model misspecification for observed data. However, the performance of the posterior predictive check procedure has thus far not been directly examined under different conditions of mixture model misspecification. This article addresses this task and aims to provide additional insight into whether or not posterior predictive checks can detect model misspecification within the context of Bayesian growth mixture modeling. Results indicate that this procedure can only identify mixture model misspecification under very extreme cases of misspecification. 相似文献
87.
西部地区优势产业的选择与区域的协调发展 总被引：8，自引：0，他引：8
杨强 《福建师范大学学报(哲学社会科学版)》2004,(4):49-53
发展优势产业是实现区域协调发展的重要环节。以优势资源为依托 ,西部地区可选择的优势产业有 :特色农业、有色金属加工和化工业、水力发电业、高新技术产业、中医药加工业以及旅游业等 ;西部地区发展优势产业必须克服或缓解薄弱的基础设施、脆弱的生态环境、较低素质的人力资源、投资资金不足和片面的优势资源观等方面的约束 相似文献
88.
王玉芝 《蒙自师范高等专科学校学报》2009,7(3):8-11
个碧石铁路是与滇越铁路配套的铁路网,它既是滇东南地区近代实业救国的典范,又是近代中国唯一的一条民营铁路。个碧石铁路是在滇越铁路的震撼声中滇东南地区的实业家和爱国乡绅自己倡导、筹资、建造、经营的民营企业。这是近代中国、近代东南亚殖民铁路格局中的奇迹。个碧石铁路的修建不仅是滇东南地区民营企业崛起的重要标志,也是近代中国民营企业的典范,是滇东南地区发展进步的标志。 相似文献
89.
印度高等教育的质量、创新和公平增长 总被引：1，自引：0，他引：1
李建忠 《大学.研究与评价》2008,(2):84-86
为迎接知识社会的到来和挑战,加强国际竞争,印度从基础设施建设、教学、科研、教师及质量评估和认证等方面提高高等教育质量,培养创新人才,实施了\"具有卓越潜力的大学\"、教师进修和本科生职业性课程等计划。在高等教育\"十一五\"规划中,印度又提出促进高等教育公平增长的思想来引导本国的高等教育发展。 相似文献
90.
Hardik Dodiya Amit Patel Dipal Patel Ashish Kaushal D. G. Vijay 《Indian journal of clinical biochemistry : IJCB》2013,28(4):403-409
The objective of study was to evaluate and correlate the pathological characteristics of breast cancer patients with estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (Her2/neu) detected by immunohistochemistry and/or fluorescent in situ hybridization method. We have conducted 2 year study of 204 cases of breast cancer at HCG-Medisurge Hospitals, Ahmedabad from 2009 to 2011. Significant correlation was found in ER and PR expression whereas no correlation was found in hormonal receptors and Her2/neu expression. ER and PR positivity increased with advancing age in breast carcinoma patients while not affecting Her2/neu expression. The expression of hormone receptors were higher in infiltrating lobular carcinoma and infiltrating duct carcinoma subtypes of breast carcinoma as compared to other subtypes such medullary and in situ carcinoma. High-grade carcinoma patients were predominantly ER/PR negative and Her2/neu positive as compared to lower grade breast carcinoma whereas high-stage carcinoma patients were ER/PR positive and Her2/neu positive as compared to lower stage breast carcinoma. 相似文献