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Fetal alcohol spectrum disorder (FASD) is the leading preventable intellectual and developmental disability. There is no safe level of alcohol consumption at any point during pregnancy. Findings of this study indicate that the information disseminated by health care professionals is not always in keeping with this understanding. Physicians and midwives appeared to be the least consistent in advocating to women that they abstain from alcohol consumption while pregnant. We explore ways in which social workers can support the medical profession to provide more consistent messaging of alcohol abstinence during pregnancy to lower the incidence of FASD.  相似文献   
3.
The Hodrick–Prescott (HP) filtering is frequently used in macroeconometrics to decompose time series, such as real gross domestic product, into their trend and cyclical components. Because the HP filtering is a basic econometric tool, it is necessary to have a precise understanding of the nature of it. This article contributes to the literature by listing several (penalized) least-squares problems that are related to the HP filtering, three of which are newly introduced in the article, and showing their properties. We also remark on their generalization.  相似文献   
4.
Consider a random variable S being the sum of a number N of independent and identically distributed random variables Xj (j = 1, 2, ...) where the number N is itself a non-negative integer-valued random variable independent of the Xj An explicit expression of the r-th cumulant of S is given in terms of the cumulants of N and Xj, Asymptotic properties of the distribution of S are also discussed.  相似文献   
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关于本次世界经济危机,马克思主义经济学家认为原因有二:一是认为这场危机是"新自由主义的失败";二是将其当作由生产过剩引发的资本主义循环性危机去理解。但是,观点二并没有解释这场经济危机为何成为了"百年不遇"的事件;而观点一也没有解释自由主义的失败是资本主义的失败。笔者认为,新自由主义是资本主义衰落的必然结果,所以,新自由主义的失败就是资本主义的失败。为此,对上述两种观点进行了否定,认为这次危机的本质是发达资本主义国家不想适应"零增长"的新的经济社会制度。另外,反对金融资本主义,认为应该重视马克思的生产性劳动理论。  相似文献   
7.
This article uses a demographic approach and data from the Health and Retirement Survey, a nationally representative sample of the U.S. population, to investigate sex differences in the length of life lived with heart disease and after a heart attack for persons in the United States age 50 and older. On average, women live longer than men with heart disease. At age 50 women can expect to live 7.9 years and men 6.7 years with heart disease. The average woman experiences heart disease onset three years older and heart attacks 4.4 years older than men.  相似文献   
8.

Background

Since age-related muscle strength loss cannot be explained solely by muscle atrophy, other determinants would also contribute to muscle strength in elderly. The present study aimed to clarify contribution of neuromuscular activation pattern to muscle strength in elderly group. From 88 elderlies (age: 61~?83 years), multi-channel surface electromyography (EMG) of the vastus lateralis muscle was recorded with two-dimensional 64 electrodes during isometric submaximal ramp-up knee extension to assess neuromuscular activation pattern. Correlation analysis and stepwise regression analysis were performed between muscle strength and the parameters for signal amplitude and spatial distribution pattern, i.e., root mean square (RMS), correlation coefficient, and modified entropy of multi-channel surface EMG.

Results

There was a significant correlation between muscle strength and RMS (r =?0.361, p =?0.001) in the elderly. Muscle thickness (r =?0.519, p <?0.001), RMS (r =?0.288, p?=?0.001), and normalized RMS (r =?0.177, p =?0.047) were selected as major determinants of muscle strength in stepwise regression analysis (r?=?0.664 in the selected model).

Conclusion

These results suggest that inter-individual difference in muscle strength in elderly can be partly explained by surface EMG amplitude. We concluded that neuromuscular activation pattern is also major determinants of muscle strength on elderly in addition to indicator of muscle volume.
  相似文献   
9.
The Hodrick–Prescott (HP) filtering is widely applied to decompose macroeconomic time series, such as real Gross Domestic Product, into cyclical and trend components. This paper presents a small but practically useful modification to this approach. The reason why this modified filtering is of practical use is that it provides not only identical trend estimates as the HP filtering but also extrapolations of the trend. We provide a proof based on a ridge regression representation of the modified HP filtering. This is mainly because it enhances our understanding of the approach.  相似文献   
10.
The Frisch–Waugh–Lovell (FWL) (partitioned regression) theorem is essential in regression analysis. This is partly because it is quite useful to derive theoretical results. The lasso regression and the ridge regression, both of which are penalized least-squares regressions, have become popular statistical techniques. This article describes that the FWL theorem remains valid for these penalized least-squares regressions. More precisely, we demonstrate that the covariates corresponding to unpenalized regression parameters in these penalized least-squares regression can be projected out. Some other results related to the FWL theorem in such penalized least-squares regressions are also presented.  相似文献   
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