Analysis of blasting vibration duration considering frequency and energy and its application.

Blasting vibration's effect on ground vibration is essentially an energy transfer and transformation process (Hongtao et al., 2010) [1]. In engineering, the blasting vibration duration is often used as an objective index to evaluate the blasting vibration hazard.

Physical activity during pregnancy and the risk of gestational diabetes mellitus: a systematic review and meta-analysis of randomised controlled trials.

Objectives: We performed a systematic review and meta-analysis to assess the effects of physical activity in preventing gestational diabetes mellitus (GDM).

Search Strategy: We searched the literature in six electronic databases and bibliographies of relevant articles.

Selection Criteria: We included randomised controlled trials on pregnant women who did not have GDM and other complications previously and had increased physical activity as the only intervention.

[Evidence-based medical approach to clinical medicine and health policy-making in the 21st century].

In the late part of the 20th century, due to the change of disease spectra, rapid increase of health expenditure and imbalanced distribution of health resources, the health management sectors and doctors increasingly demand the scientific decision-making. With the development of clinical evidences and research, evidence-based medicine (EBM) became emerged in the early 1990's. EBM, the medical science in compliance with the best available clinical evidence, integrates clinical epidemiology (CE), systematic reviews (SRs) and health technology assessment (HTA) as the major technology, to emphasize that the clinical practice should be based on the combination of the best available clinical evidence, medical experiences and patient desire to cope with the demand of medical decision-making.