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1.
Nuria Infante-Torres Milagros Molina-Alarcón Ana Rubio-Álvarez Julián Rodríguez-Almagro Antonio Hernández-Martínez 《Women and birth : journal of the Australian College of Midwives》2018,31(5):e318-e324
Aim
To assess the relationship between the duration of the second stage of labour and postpartum anaemia during vaginal birth.Methods
An observational, analytical retrospective cohort study was performed at the “Mancha-Centro Hospital” (Spain) during the 2013–2016 period. Data were collected from 3437 women who had a vaginal birth. Postpartum anaemia was defined as a haemoglobin level below 11 g/dL at 24 h postpartum. A univariate analysis was used for potential risk factors and a multivariate analysis with binary logistic regression to control for possible confounding factors.Findings
The incidence of postpartum anaemia was 42.0%. The risk of postpartum anaemia did not increase in nulliparous women whose duration of the second stage of labour exceeded 4 h. Compared with multiparous women who delivered between 0 and 3 h, multiparous women with a duration of the second stage of labour beyond 3 h were at higher risk of postpartum anaemia (OR = 2.43 [1.30–4.52]).Conclusion
The duration of the second stage of labour beyond 4 h is safe for postpartum anaemia in nulliparous women. However in multiparous women, monitoring should increase if the second stage of labour exceeds 3 h given the increased risk of postpartum anaemia. 相似文献2.
Proportional hazards are a common assumption when designing confirmatory clinical trials in oncology. This assumption not only affects the analysis part but also the sample size calculation. The presence of delayed effects causes a change in the hazard ratio while the trial is ongoing since at the beginning we do not observe any difference between treatment arms, and after some unknown time point, the differences between treatment arms will start to appear. Hence, the proportional hazards assumption no longer holds, and both sample size calculation and analysis methods to be used should be reconsidered. The weighted log‐rank test allows a weighting for early, middle, and late differences through the Fleming and Harrington class of weights and is proven to be more efficient when the proportional hazards assumption does not hold. The Fleming and Harrington class of weights, along with the estimated delay, can be incorporated into the sample size calculation in order to maintain the desired power once the treatment arm differences start to appear. In this article, we explore the impact of delayed effects in group sequential and adaptive group sequential designs and make an empirical evaluation in terms of power and type‐I error rate of the of the weighted log‐rank test in a simulated scenario with fixed values of the Fleming and Harrington class of weights. We also give some practical recommendations regarding which methodology should be used in the presence of delayed effects depending on certain characteristics of the trial. 相似文献
3.
The article investigates whether Austrian sociological research empirically addressed social class conceptions between 1945 and 1990. Contrary to the German reception, we find that, indeed, during the whole period scientific publications analyzed social relations and social change from a class perspective with an empirical approach. We embed this research in its historical context in order to work out the implicit explanations given concerning the existence of social inequalities. Moreover, we work out if post-World War II Austrian class analysis did link its work to the Austro-Marxist tradition that flourished between the two World Wars. The empirical focus of the article lies on scientific publications with an empirical approach to social classes and social change. 相似文献
4.
Open innovation and absorptive capacity are two concepts based on the idea that companies can leverage the knowledge generated externally to improve their innovation performance. The aim of this paper is to analyse the joint effect of open innovation and absorptive capacity on a firm's radical innovation. Open innovation is expressed in terms of external search breadth and depth strategies and absorptive capacity is described by distinguishing between potential and realized absorptive capacity. In order to test our hypotheses, we carried out empirical research in firms operating in high-technology industries. The results indicate that internal routines and processes for absorbing external knowledge help explain radical innovation as they show a significant effect of potential and realized absorptive capacity. Also, there is a moderating effect of absorptive capacity on open innovation. Specifically, potential absorptive capacity exerts a positive effect on the relationship between external search breadth and depth and radical innovation. Realized absorptive capacity moderates the influence of external search breadth. These findings confirm the complementary nature of absorptive capacity and open innovation search strategies on radical innovation. 相似文献
5.
Luis Villar-Fidalgo María del Mar Espinosa Escudero Manuel Domínguez Somonte 《生产规划与管理》2019,30(8):624-638
Not only ETO (Engineering to Order), but even serial production industry should know how to deal with projects and their schedule: plant commissioning, shutdown, introducing new products and similar circumstances should be managed with adequate planning and resource allocation techniques to create a schedule useful in decision making during the execution. The current complex reality, with evolving technologies and fierce pressure to reach the market as soon as possible, pushes the project managers to use more advanced techniques than waterfall planning, such as agile or lean. It also requires them to take a holistic view and manage concurrent tasks in complex projects. The contributions of this paper are two: the proposal to control specific parallel groups of waterfall activities under uncertain environments, which can lead to iterations and reworks, as a single concurrent Activity Managed by Kanban Methods (AMKM). This activity can be subsequently embedded into traditional scheduling approaches as CPM-PERT. The second contribution is the feasibility of its application in industrial environments due to the affordability of simulation software. Two use cases are shown as evidence. It is not a disruptive proposal, but a kaizen action based on very mature technologies. Finally, it is suggested some improvements to be implemented in Project Management Software due to this ‘kaizen’ proposal. 相似文献
6.
Social Indicators Research - Monitoring progress towards the Sustainable Development Goals by 2030 requires the global community to disaggregate targets along socio-economic lines, but little has... 相似文献
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Julia O'Connell Davidson 《Gender, Work and Organization》1995,2(1):1-10
This paper draws on an ethnographic study of a self-employed prostitute, her receptionists and her clients. It describes the prostitute's business and her working life, and considers the dynamics of power and control within the prostitute-client exchange. The paper argues that issues of control and consent in prostitution are more complex than many current feminist analyses suggest. 相似文献