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91.
以产业化经营推动我省粮食经济发展   总被引:1,自引:0,他引:1  
在分析了我省粮食经济的成就和主要问题之后,提出以产业化经营推动我省粮食经济发展.指出我省农业产业化存在的问题是区域分工、产业结构调整和企业模式选择并进行分析.  相似文献   
92.
通过对近十年我国体育教师专业能力的文献收集,将其分为中小学和大学两大类,并对每类文献做结构、现状、策略的综述。研究方法为文献资料法,逻辑分析法。研究结果:学者对体育教师专业能力结构的见解具有交叉性,但缺少统一的认识,研究范围较小,不足以代表合格教师所应具备的专业能力;现状和策略的研究较为陈旧,对提出的策略没有进一步跟进,策略缺乏创新,需要更深层次的研究。  相似文献   
93.
《四时田园杂兴》是范成大退居石湖创作的一组诗歌,自问世以来颇受瞩目,但至今仍少有人关注其特殊的结构形式。作者选择这一特殊结构形式有其特殊的寓意:纪念伴随其出生以来历久弥深的国耻。这一选择的驱动力来自我国的文化传统、作者的经历及对诗歌风格的好尚。  相似文献   
94.
新罗时期的国语诗歌又称之为乡歌,它是朝鲜半岛最古老的国语诗歌。乡歌作品共有25首,其中《三国遗事》所载14首,《均如传》所载11首。通过对新罗乡歌作品结构的分析,可以进一步了解新罗国语诗歌的构成形式。《三国遗事》所载14首乡歌作品因其类型的多样性和记录方法的特殊性,在结构层面上也表现出了独特的一面。  相似文献   
95.
Abstract

Maternal dietary habits influence maternal and foetal health, representing a pathway for intervention to maximise pregnancy outcomes. Advice on energy intake is provided on a trimester basis, with no additional calories required in the first trimester and an additional 340?kcal?d?1 and 452?kcal?d?1 needed for the second and third trimesters. Energy intake depends on pre-gravid body mass index (BMI); underweight women are recommended an increase of 150, 200 and 300?kcal?d?1 during the first, second and third trimester, normal weight women an increase of 0, 350 and 500?kcal?d?1 and obese women an increase of 0, 450 and 350?kcal?day?1. The recommendations for carbohydrate and protein intake are 175?g?d?1 and 0.88–1.1?g?kgBM?d?1, with no change to fat intake. The number of pre-gravid obese women is rising; therefore, we need to regulate weight in women of childbearing age and limit gestational weight gain to within the recommended ranges [overweight women 6.8–11.3?kg and obese women 5.0–9.1?kg]. This can be achieved using nutritional interventions, as dietary changes have been shown to help with gestational weight management. As pregnancy has been identified as a risk factor for the development of obesity, normal weight women should gain 11.5–16.0?kg during pregnancy. While some research has shown that dietary interventions help to regulate gestational weight gain and promote postpartum weight loss to some extent, future research is needed to provide safe and effective guidelines to maximise these effects, while benefitting maternal and foetal health.  相似文献   
96.
Virtual microscopy (VM) is a widely used teaching method in Medical Education in many developed countries. In Brazil, however, this is not the case for most medical schools, considering Brazilian social inequality and uneven access to technology. Recently, the Covid-19 pandemic has also challenged Universities to seek and make a transition toward more effective methods of full-time online education. Thus, the main goal of this work was to verify student's perception and academic performance, assessed upon VM implementation in a Brazilian Medical School. Ribeirao Preto Medical School students answered a 26-question survey with regards to optical microscopy (OM) and VM. Academic performance was compared between participants that were (year of 2019) or were not (year of 2015) exposed to VM. Taken the results together, subjective impressions such as handling, suitability, learning effectiveness, and pleasure using the tools, have shown a higher score for virtual microscopy (median = 29), when compared to optical microscopy (median = 24) with a P-value < 0.001 by Wilcoxon rank test, upon measurement using an ordinal scale. Regarding academic performance, no statistically significant differences were found between groups (P-value = 0.38, Cohen's d = 0.19). Therefore, VM proved to be adequate to the Brazilian medical education in light of Brazilian social contexts and Covid-19 pandemic.  相似文献   
97.
Since Cronbach's (1951) elaboration of α from its introduction by Guttman (1945), this coefficient has become ubiquitous in characterizing assessment instruments in education, psychology, and other social sciences. Also ubiquitous are caveats on the calculation and interpretation of this coefficient. This article summarizes a recent contribution (Andrich, 2015) on the use of coefficient α which complements these many caveats. It shows that in the presence of a simple bifactor structure of a scale where unique components of variance are homogeneous in magnitude, three components of variance and the common latent common correlation among the subscales can be calculated from the ratio of two calculations of α, one at the level of the items, the other at the level of the subscales. It was suggested that these two ready calculations and their interpretation, and the reporting of all four indices in the analysis of scales with a subscale structure, would reduce the misinterpretation of this coefficient. An illustrative example of the application of the calculations is also shown.  相似文献   
98.
The high prevalence of child sexual abuse (CSA) is concerning, particularly as survivors are at increased risk for multiple adverse outcomes, including poor mental health across the lifespan. Children born at an extremely low birth weight (ELBW; <1000 g) and who experience CSA may be a group that is especially vulnerable to psychopathology later in life. However, no research has considered the mental health risks associated with being born at ELBW and experiencing CSA. In this study, we investigated the mental health of 179 ELBW survivors and 145 matched normal birth weight (NBW; >2500 g) participants at ages 22–26 and 29–36. At age 22–26, CSA was associated with increased odds of clinically significant internalizing (OR = 7.32, 95% CI: 2.31–23.23) and externalizing (OR = 4.65, 95% CI: 1.11–19.51) problems among ELBW participants exposed to CSA compared to those who did not, though confidence intervals were wide. At age 29–36, CSA was linked to increased odds of any current (OR = 3.43, 95% CI: 1.08–10.87) and lifetime (OR = 7.09, 95% CI: 2.00–25.03) non-substance use psychiatric disorders, however, this did not hold after adjustment for covariates. Statistically significant differences in mental health outcomes were not observed in NBW participants exposed to CSA compared to NBW participants who were not exposed. Survivors of significant perinatal adversity who are also exposed to CSA may be at higher risk for psychopathology through the fourth decade of life.  相似文献   
99.
历史认识中人本思想提升的一个理论结果,是史学家、思想家对于包括社会结构与历史演进等理论的思考获得深入。古代中国史学家、思想家对于社会结构与历史演进的理论思考,与早熟、发达的国家制度有关,与古代中国特有的史官制度及其文化形态、史学文化传统也有密切的关系。从公元4世纪到16世纪这1000多年观念的发展来看,史家对于社会结构的认识,大致延续了《史记》、《汉书》的传统,体现了大体一致的对社会结构的认识,即呈天、地、人、政治、经济、刑法、军事、政治制度、选官制度、文化的结构顺序。随着社会的发展,中国的史学家、思想家对于社会结构及其历史演进的理解亦不断深化,尤其是对社会经济及其历史意义的认识更是日益丰富。  相似文献   
100.
大尺寸薄壁钢筋混凝土结构,对温度的变化和基础的不均匀沉降较为敏感。制定合理的施工方案,材料的合理选择、施工流程精心组织保证了裂缝控制效果良好。  相似文献   
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