Propagation of the radially polarized Airy vortex beams in uniaxial crystals orthogonal to the optical axis.

We introduce the radially polarized Airy vortex beams (RPAiVBs) and analytically study their propagation in uniaxial crystals orthogonal to the optical axis. We mainly discuss the effects of the vortex and the ratio of the extraordinary index (ne) to the ordinary index (no) on the propagation properties of the RPAiVBs involving the intensity distributions, the maximum intensity, the radiation forces, the trajectory, and the velocity. The RPAiVBs evolve into the beams produced by the x direction electric field (RPAiXVB) and the y direction electric field (RPAiYVB). It is shown that with the increase in the order of the vortex, the maximum intensity and the radiation forces of the RPAiVBs are greatly enhanced; besides, the intensity focusing position of the RPAiVBs is farther. Furthermore, with the ratio of ne to no increasing, the trajectory of the RPAiXVBs is farther from x=0 mm, and the acceleration is bigger in the x-z plane, but they are opposite in the y-z plane.

Exploration of registration and the risk of bias in acupuncture randomised controlled trials: a systematic review protocol.

BACKGROUND: Randomised controlled trials (RCTs) are the predominant type in acupuncture clinical research, and the publications have increased rapidly in recent years, but there is a prevalence of the high risk of bias and poor methodological design in acupuncture RCTs. Clinical trial registration can improve the transparency and credibility of studies by disclosing key information in advance. However, the registration in acupuncture RCTs is not satisfactory, as there is widespread of the under-registration, inconsistency with published studies and insufficient disclosure of key methodological information. Whether registration can reduce the risk of bias in acupuncture RCTs and improve data transparency has not been fully explored. Therefore, we constructed this study to investigate the association between registration and risk of bias and data sharing level in acupuncture RCTs. METHODS: Seven databases including MEDLINE, EMBASE, CENTRAL, CBM, CNKI, Wanfang and VIP databases will be systematically searched between 1 January 2014 and 31 March 2024, for acupuncture RCTs. Two reviewers will independently extract data using a predefined standardised format and perform secondary validation. The characteristics and data sharing level of the included studies will be summarised. The risk of bias of included RCTs will be assessed by the revised Cochrane risk-of-bias tool for randomised trials. The risk of bias and registration in acupuncture RCTs will be analysed by logistic or quantile regression analyses (depending on the number of minimum events). The data sharing level and registration will be analysed by quantile regression analyses. ETHICS AND DISSEMINATION: As the systematic review aims to consolidate info from published sources, ethical approval is not necessary for this study. The study's findings will be submitted to a peer-reviewed academic journal and disseminated via conference presentations. This protocol has been registered in Open Science Framework Registries.