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1.
This study examined biological sex differences in the development of mild cognitive impairment (MCI) and probable Alzheimer’s disease (AD) development as predicted by changes in the hippocampus or white matter hyperintensities. A secondary data analysis of the National Alzheimer’s Coordinating Center Uniform Data Set was conducted. We selected samples of participants with normal cognition at baseline who progressed to MCI (n = 483) and those who progressed to probable AD (n = 211) to determine if hippocampal volume or white matter hyperintensities (WMH) at baseline predicted progression to probable AD or MCI and whether the rate of progression differed between men and women. The survival analyses indicated that changes in hippocampal volumes affected the progression to probable AD (HR = 0.535, 95% CI [0.300–0.953]) only among women. White men had an increased rate of progression to AD (HR = 4.396, CI [1.012–19.08]; HR = 4.665, 95% CI [1.072–20.29]) compared to men in other race and ethnic groups. Among women, increases in hippocampal volume ratio led to decreased rates of progressing to MCI (HR = 0.386, 95% CI [0.166–0.901]). Increased WMH among men led to faster progression to MCI (HR = 1.048. 95% CI [1.011–1.086]). Women and men who were older at baseline were more likely to progress to MCI. In addition, results from longitudinal analyses showed that women with a higher CDR global score, older age at baseline, or more disinhibition symptoms experienced higher odds of MCI development. Changes in hippocampal volumes affect the progression to or odds of probable AD (and MCI) more so among women than men, while changes in WMH affected the progression to MCI only among men.  相似文献   
2.
Most studies that have examined whether a child’s death influences parental relationship stability have used small-scale data sets and their results are inconclusive. A likely reason is that child loss affects not only the risk of parental separation, but also the risk of having another child. Hence parity progression and separation must be treated as two competing events in relation to child loss. The analysis in this paper used Finnish register data from 1971 to 2003, covering over 100,000 married couples whose durations of both first marriage and parenthood could be observed. We ran parity-specific Cox regressions in which process time started from the birth of each additional child. All marriages included women of childbearing age, none of whom had experienced any child death on entering the analysis. We find that child loss only modestly influences the divorce risk, whereas its effect on the risk of parity progression is considerable.  相似文献   
3.
Many oncology studies incorporate a blinded independent central review (BICR) to make an assessment of the integrity of the primary endpoint, progression free survival. Recently, it has been suggested that, in order to assess the potential for bias amongst investigators, a BICR amongst only a sample of patients could be performed; if evidence of bias is detected, according to a predefined threshold, the BICR is then assessed in all patients, otherwise, it is concluded that the sample was sufficient to rule out meaningful levels of bias. In this paper, we present an approach that adapts a method originally created for defining futility bounds in group sequential designs. The hazard ratio ratio, the ratio of the hazard ratio (HR) for the treatment effect estimated from the BICR to the corresponding HR for the investigator assessments, is used as the metric to define bias. The approach is simple to implement and ensures a high probability that a substantial true bias will be detected. In the absence of bias, there is a high probability of accepting the accuracy of local evaluations based on the sample, in which case an expensive BICR of all patients is avoided. The properties of the approach are demonstrated by retrospective application to a completed Phase III trial in colorectal cancer. The same approach could easily be adapted for other disease settings, and for test statistics other than the hazard ratio. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
4.
运用主成分分析法筛选指标构建财务危机预警指标体系,该体系包含4个因子9个指标。采用突变级数法编制财务危机预警指数,对我国创业板260家上市公司进行了预警。研究结果表明:创业板上市公司盈利状况和现金流量状况相对较好,偿债能力和营运能力欠佳。最终确定财务预警指数参考临界值为0.743。  相似文献   
5.
We describe a regression-based approach to the modelling of age-, order-, and duration-specific period fertility, using retrospective survey data. The approach produces results that are free of selection biases and can be used to study differential fertility. It is applied to Demographic and Health Survey data for Ethiopia, Kenya, Tanzania, and Zimbabwe to investigate differential trends in fertility by education. Parity progression fell and the intervals following each birth lengthened between the 1970s and 2000s in all four countries. Fertility fell most among women with secondary education. In contrast to other world regions, postponement of successive births for extended periods accounted for much of the initial drop in fertility in these African countries. However, family size limitation by women with secondary education in Ethiopia and Kenya and longer birth spacing in Zimbabwe also played significant roles. Thus, birth control is being adopted in Eastern Africa in response to diverse changes in fertility preferences.  相似文献   
6.
对农产品物流产业发展水平进行客观、准确的分析与评估,可为政府部门优化与调整产业发展、合理制定产业规划提供科学依据。运用突变级数法与离差最大化法构建农产品物流产业评估模型,并选取广东和山东两省20102014年相关数据对构建的评估模型进行实例分析。结果表明:广东省农产品物流产业发展的优势主要体现在信息化水平与经济基础两方面,基础设施建设则是当前制约其产业发展的关键因素;而庞大的产业规模是现阶段支撑山东省农产品物流产业发展的重要力量。改进的突变级数评估模型既克服了主观赋权的局限,又不失科学性和合理性,计算简单,具有重要实用价值。  相似文献   
7.
通过从宏观结构到微观成分的功能文体分析,就大学英语语篇教学研究提供一种多维的理据:对语篇进行宏观结构的分析,有利于掌握其组织机制;而运用情景语境分析和主位推进分析,能对揭示语篇构成的环境因素、语篇的发展脉络起到总领的作用;恰当的衔接手段分析,则可以为读者理解语篇的连贯方式和领会语篇遣词的技巧发挥作用。  相似文献   
8.
Disabled people are under-represented in higher education (HE), especially in senior posts. This article reports research on the perspectives of career progression into leadership held by disabled staff in one post-1992 university. Findings indicated that some participants were already engaged in leadership or aspired to such roles, and reported positive experiences. However, participants also experienced barriers to progression, including a lack of awareness of equality and diversity among managers and colleagues, inadequate professional development opportunities and the competitive organisational culture of management that could impact on their health and work–life balance. We conclude that disabled staff in HE do not yet have equal opportunities for progression into leadership roles compared with their non-disabled peers. There is a need for realignment of the culture of leadership and management to make it more compatible with the full inclusion of disabled staff in HE such that their unique contributions are valued.  相似文献   
9.
The spectre of environmental ‘domestic extremism’ has long been postulated by police leaders and security analysts in Britain. It is a narrative that has justified the commitment of enormous amounts of government resources towards police intelligence work directed at non-violent direct action campaigns. Most controversially, this has included the long-term infiltration of environmental (and other) activist groups by undercover police. This article provides a critical analysis of the justifications put forward in support of the covert surveillance of environmental activists in Britain. The paper proceeds by way of a single case study – a high profile, environmental direct action protest in the north of England – in order to reveal the levels of abuse, manipulation and deception at the basis of undercover protest policing. Through their court case, the activists involved with this action were able to obtain rare insights into the police authorisation documents for the undercover operation that had led to their arrests. An analysis of these documents provides us with a glimpse of the contradictory justifications given by senior police officers for infiltration – now under scrutiny by a public inquiry.  相似文献   
10.
An increasing number of Australia’s ageing population are aging with long-term physical impairments. This study explored the life experiences of this group using a qualitative approach. In-depth interviews were conducted with 10 disabled Victorians, aged between 51 and 84 years, and an inductive thematic analysis undertaken. A relationship was found between the adaptive strategies that participants developed as they moved through life phases and the impairment stages. The implications of the emergence of a cyclical process of adaptation across the life course. and particularly in respect of aging, delivery of aged-care services and social workers in this sector are discussed.  相似文献   
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