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21.
《Women and birth : journal of the Australian College of Midwives》2020,33(3):294-299
BackgroundThe prevalence of high body mass index is increasing amongst women of child bearing age. High maternal body mass index has ramifications for both mother and baby including increased health risks from gestational diabetes mellitus, caesarean section and stillbirth. Despite the increasing prevalence of high maternal body mass index little is known of the experiences of these women regarding nutrition information access and use during the antenatal period.MethodsA qualitative study using individual interviews was undertaken at a tertiary hospital in south-eastern Australia. Twenty-Eight women with a body mass index ≥30 kg/m2 participated. Interviews were audio recorded, transcribed, cross-checked for consistency and entered into a word processing document for further scrutiny. Data was analysed using interpretative phenomenological analysis (IPA). In any phenomenological study the researcher’s objective is to elicit the participant’s views on their lived experiences.FindingsThree major themes emerged: (1) Nutrition-related information attainment; (2) Nutrition-related information management; (3) Nutrition-related information needs and wants.ConclusionThe findings from this study may assist the future development and dissemination of nutrition-related information for pregnant women with a high body mass index. Women want more individualised support regarding nutritional requirements during pregnancy. 相似文献
22.
上证50ETF期权上市至今,中国期权市场表现出很多与美国市场显著不同的特征,由此引申出关于美国的经验是否适用于中国、中国期权市场定价是否有效的争论。
基于2015年4月16日至2017年12月29日的中国上证50ETF期权数据和美国S&P500期权数据,以股指收益率与波动率的相关系数以及股指收益率的历史分布为工具,从整体特征和横截面特征两个维度,研究隐含波动率与实际波动率的理论关系;以使用期权市场数据计算得到的隐含波动率数据、波动率微笑和实际波动率数据、0Delta组合的超额收益为工具,研究隐含波动率与实际波动率的实际关系;针对上述理论关系和实际关系进行中美比较。由于理论关系研究中未使用期权数据,因此通过比较上述两个维度下的理论关系与实际关系的差异,可以对中国期权市场的绝对定价效率和相对定价效率进行探究。
研究结果表明,在整体特征上,美国期权市场中隐含波动率与实际波动率的理论关系与实际关系相符,美国期权市场在绝对定价效率维度上有效;中国市场,尤其是牛市样本中,隐含波动率与实际波动率的理论关系与实际关系不相符,中国期权市场在绝对定价效率维度上被高估。在横截面特征上,美国期权市场中隐含波动率与实际波动率的理论关系与实际关系相符,美国期权市场在相对定价效率维度上有效;中国市场,尤其是牛市样本中,隐含波动率与实际波动率的理论关系与实际关系不相符,中国期权市场在相对定价效率维度上无效,低行权价的期权被低估、高行权价的期权被高估。在上述两个特征的研究中,相应构造的0Delta组合(策略)同样支持上述结论。
通过中美两国隐含波动率与实际波动率的理论关系与实际关系的研究,发现中美两国的市场状况存在差异,在中国期权市场上的研究和交易不能简单照搬美国经验,要仔细研究和利用中国市场的当前特征。监管层也应完善中国股票和期权市场制度,降低期权交易成本,实行股票现货交易(t+0)制度,完善股票现货做空机制,以使套利机制可以正常发挥作用,改善当前上证50ETF期权市场被高估的现象,使期权的保险功能正常发挥作用。 相似文献
23.
1977~2009年人口学CSSCI期刊论文作者统计分析 总被引:3,自引:0,他引:3
论文是科研人员从事科学研究产生成果的重要表现形式,作者数量和文献数量之间的关系是遵循科学研究发展的客观规律。通过使用文献计量学的方法,对7种人口学CSSCI期刊自创刊起至2009年的全部论文进行分析,主要发现:(1)7种期刊不同论文数量的作者占作者总人数的概率分布都遵循Lotka定律,新老作者结构合理;(2)7种期刊新增量都显著低于理论最佳值,说明学术研究队伍非常稳定,但是活力不足,容易出现作者老化现象。 相似文献
24.
20世纪70年代以来,志愿者组织在全球范围兴起并得到发展,逐渐成为现代社会发展的一支活跃力量,在全球掀起了开展志愿服务的热潮。大学生志愿者作为我国志愿服务的重要参与主体,在志愿服务中起到了举足轻重的作用。在两岸和平发展新时期,两岸出现了大交流、大合作、大发展的新局面。作为志愿服务的主力军,两岸大学生志愿服务动机和激励机制的比较,有利于促进两岸大学生志愿服务合作机制的建立。 相似文献
25.
Kristin Turney Jason Schnittker Christopher Wildeman 《Journal of marriage and the family》2012,74(5):1149-1165
As the American imprisonment rate has risen, researchers have become increasingly concerned about the implications of mass imprisonment for family life. The authors extend this research by examining how paternal incarceration is linked to perceived instrumental support among the mothers of inmates' children. Results from the Fragile Families and Child Wellbeing Study (N = 4,132) suggest that recent, but not current, paternal incarceration is independently associated with less maternal perceived instrumental support and that this association persists after adjusting for a rich set of control variables, including prior perceived instrumental support. For families of recently incarcerated men, incarceration may be a double strike, simultaneously increasing the need for instrumental support while decreasing its availability when incarcerated fathers return to the community. 相似文献
26.
Pathways of disadvantage: Explaining the relationship between maternal depression and children’s problem behaviors 总被引:1,自引:0,他引:1
Kristin Turney 《Social science research》2012,41(6):1546-1564
A large body of literature documents that children of depressed mothers have impaired cognitive, behavioral, and health outcomes throughout the life course, though much less is known about the mechanisms linking maternal depression to children’s outcomes. In this paper, I use data from the Fragile Families and Child Wellbeing Study to estimate and explain the consequences of maternal depression for 5-year-old children’s internalizing and externalizing problem behaviors. Ordinary least squared (OLS) regression models and propensity score models show that children exposed to both chronic and intermittent maternal depression have more problem behaviors than their counterparts with never depressed mothers. Results also show that economic resources and maternal parenting behaviors mediate much of the association between maternal depression and children’s problem behaviors, but that relationships with romantic partners and social support do little to explain this association. This research extends past literature by illuminating some mechanisms through which maternal depression matters for children; by utilizing longitudinal measures of depression; by employing rigorous statistical techniques to lend confidence to the findings; and by using a large, diverse, and non-clinical sample of children most susceptible to maternal depression. Given that early childhood problem behaviors lay a crucial foundation for short- and long-term life trajectories, the social consequences of maternal depression may be far-reaching. 相似文献
27.
青年组织是青年群体活动、成长和发展的集体,也是培育社会资本的重要平台与形式。当代政党和非政党组织的一个共性特征和普遍做法是通过青年组织开展民众工作,广泛吸纳青年社会精英,务实政党民意基础,完成政治社会化过程。通过对台港澳地区相关青年组织的考察,梳理其开展民众工作的具体理念和路径,有益于探寻青年组织深入社会、服务社会的内在规律,对我国其他地区同类型青年组织的发展起到一定的借鉴作用。 相似文献
28.
隋唐时期,《论语》研究无论是在数量上,还是在质量上较前代都有所下降。主要原因在于,在统一经学的旗帜下,统治者垄断了经典话语的解释权;鼓励诵读的科举制度以及以古为上的学术观念,限制了经学的发展空间;崇道尊佛政策的实行,也在一定程度上冲击了儒家经学的地位。如此的学术观念,如此的考试制度,如此的宗教政策,奢望儒家学术有大的创新与发展是不可能的。因此,经学衰落了,《论语》学也衰落了。 相似文献
29.
Personal Values as Mitigating Factors in the Link Between Income and Life Satisfaction: Evidence from the European Social Survey 总被引:1,自引:0,他引:1
Using data from the first two rounds of the European Social Survey, we examine the link between income, reference income and
life satisfaction across Western Europe. We find that whilst there is a strong positive relationship between income and life
satisfaction, reference or comparison income exerts a strong negative influence. Interestingly, our results confirm the importance
of personal values and beliefs not only as predictors of subjective well-being, but also as mitigating factors in the relationship
between income, reference income and life satisfaction. While our findings provide additional empirical support for the relative
utility hypothesis, they are also consistent with Rojas’ (J Econ Psychol 28:1–14, 2007) Conceptual-Referent-Theory (CRT), which is based on the premise that the salience of income and comparison income depends on one’s intrinsic values
and personal beliefs.
相似文献
Yannis GeorgellisEmail: |
30.
M. B. M. B. K. Gawarammana 《统计学通讯:模拟与计算》2017,46(3):2103-2120
In this study, some methods suggested for binary repeated measures, namely, Weighted Least Squares (WLS), Generalized Estimating Equations (GEE), and Generalized Linear Mixed Models (GLMM) are compared with respect to power, type 1 error, and properties of estimates. The results indicate that with adequate sample size, no missing data, the only covariate being time effect, and a relatively limited number of time points, the WLS method performs well. The GEE approach performs well only for large sample sizes. The GLMM method is satisfactory with respect to type I error, but its estimates have poorer properties than the other methods. 相似文献