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Synthetic wideband signals can obtain a wide spectrum and thus achieve a high range resolution by synthesizing separately emitted signals. A synthetic wideband range profiling method for moving targets based on phase‐derived velocity measurement is proposed. Highly accurate velocity measurement results are obtained by analysing the echo phase information of a moving target, and the accuracy of the velocity estimation results can meet the requirement of the velocity compensation in the synthetic wideband range profiling process. After analysis of the spectrum envelope and the phase of a moving target, a method for synthesizing wideband signals in the frequency domain, thus obtaining a high‐resolution range profile, is developed. The constraint conditions for the motion compensation and synthesis process are analysed and discussed by simulation, and the effectiveness of the proposed method is verified under various circumstances.

To deal with the problem of aerodynamic and stealth integrated optimization of DSI inlet, a multi-objective optimization study on aerodynamic and stealth of the DSI inlet is carry out which based on the deformation of the three-dimensional compression bump surface. The FFD parametric method is used to parameterize the bump surface; CFD calculation based on RANS equations is used to analyze the aerodynamic performance of the DSI inlet, large element physical optical method and uniform theory of diffraction are used to calculate RCS of the DSI inlet; And ASMOPSO algorithm with the Kriging surrogate model which based on the expect hyper-volume improvement infill criterion is adopted for integrated optimization design. The results of DSI inlet aerodynamic and stealth integrated optimization exhibit considerable improvement.

This paper presents an efficient multi-objective optimization method, focusing on aerodynamic optimization of a diverterless supersonic inlet (DSI) in transonic and supersonic flight conditions. The DSI inlet, through scrutinizing the Bump shape has potential to attain greater aerodynamic performance on exit plane of inlet. However, the high cost of computational fluid dynamic (CFD) simulations raises a significant challenge in the DSI optimization process. In order to obtain solution set in few numbers of objective function calls, a meta-model multi-objective particle swarm optimization (MOPSO) method is proposed based on a self-adaptive Kriging surrogate model, and applied to solve this kind of costly black-box optimization problem. The Kriging model is updated by using a dynamic expected hyper-volume improvement (EHVI) sample metric, which is developed by analyzing disadvantages of the original sample criterion. With the help of the dynamic sample metric, simulation results show that the surrogate-based MOPSO algorithm can obtain plenty enough non-dominated solutions and achieve high precision in the approximation of the Pareto front. In terms of DSI inlet optimization, the bump shape is parameterized by free form deformation (FFD) method, and the total pressure distortions of inlet exit plane are treated as two minimization objectives under transonic and supersonic flight conditions. A well distributed non-dominated solution set is generated by the proposed algorithm within the context of a small call number of cost evaluations, and optimized inlet configurated by the selected solution has better aerodynamic characteristics compared with the initial inlet.

Background: As the results of previous systematic reviews and meta-analyses on acupuncture for polycystic ovary syndrome (PCOS) have provided inconsistent evidence. This overview of systematic reviews (SRs) and meta-analyses will aim to critically appraise the methodology and reporting quality of the relevant SRs and meta-analyses with the aim of identifying whether acupuncture could provide an effective treatment for patients with PCOS or not. Methods: Electronic databases including MEDLINE via Ovid, EMBASE, PubMed, Cochrane library, China National Knowledge Infrastructure (CNKI), Chinese Scientific Journal Database (VIP database), and Wanfang Database will be searched for related SRs and meta-analyses from inceptions to the search date without language restrictions. Two reviewers will independently select SRs and meta-analyses and collect related data, and a third reviewer will be introduced if any disagreement happened during the assessing. The Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) and the latest Assessment of Multiple Systematic Reviews 2 (AMSTAR2) checklists will be employed to evaluate the reporting and methodology quality. Results: This overview will be published in a peer-reviewed journal. Conclusion: This overview will identify related SRs and meta-analyses of acupuncture for treating PCOS. Ethics and dissemination: Ethics approval and patient consent are not required as this study is an overview based on published systematic reviews and meta-analyses.

The phase-derived velocity measurement (PDVM) method based on range profiles cross-correlation (RPCC) can achieve high precision velocity estimation of Doppler centroid for complex targets, and the PDVM satisfied the precision requirements of envelope alignment and phase adjustment for ISAR imaging, that is, the PDVM method can be employed to attain target translational reconstruction. On this basis, this paper proposes an interferometric inverse synthetic aperture radar (InISAR) imaging method based on translational reconstruction. This method can obtain high-quality ISAR images by compensating the translational velocity at the target's Doppler centroid of different channel echoes. Moreover, the translational reconstruction also indirectly achieved image registration. Compared with the traditional approaches, the proposed method is not only suitable for low signal-to-noise ratio (SNR), but also simple to implement. Furthermore, it can better ensure the coherence between different channels of ISAR images, that is, the InISAR imaging results with higher precision can be obtained. The correctness and robustness of the proposed method are verified by the measured data of civil aircraft.

The target micro-motion features contain unique structural information and motion information, which can be utilized as an important basis for target recognition. At present, the main constraints of micro-motion feature extraction for high-speed targets include that the translational compensation is inaccurate, the scattering points are difficult to distinguish, the micro-motion amplitude is small, the data rate is not high enough, and so forth. The phase-derived velocity measurement (PDVM) method based on wideband radar has phase-magnitude velocity measurement precision, which can accurately reconstruct the target motion while ensuring high data rate, and meet the micro-motion measurement requirements of high-speed targets. In this paper, a PDVM method for high-speed targets based on wideband direct sampling LFM radar is proposed. The high-precision velocity measurement performance and micro-motion measurement capability of the proposed method are verified by simulation.

Background: Psoriasis is a chronic immune-mediated inflammatory skin disease, with over-activated interleukin (IL)-17-producing CD4+ T cells (Th17) and repressed regulatory T (Treg) cells. IL-21 is a Th17-related cytokine and plays an important role in the pathogenesis of psoriasis. However, the mechanism by which IL-21 affects the pathogenic progress of psoriasis remains poorly understood. Methods: IL-21 and IL-21 receptor (IL-21R) expression in normal and psoriatic lesional skin were determined by immumohistochemical staining, immunofluorescence staining, and western blotting. The levels of IL-21, IL-17A, and IL-22 in the culture supernatants were measured by enzyme-linked immunosorbent assay (ELISA). The level of IL-10 in the culture supernatants was measured by cytometric bead array (CBA). The mRNA expression levels were assessed by quantitative polymerase chain reaction (qPCR). CD4+ T cells were isolated from the peripheral blood mononuclear cells (PBMCs) from the psoriasis patients and healthy individuals and then treated with or without IL-21 for 3 days. The proportions of Th17 and Treg cells were determined by flow cytometric analysis. Results: IL-21 and IL-21R were highly expressed in the lesional skin and peripheral blood of psoriasis patients. IL-21 promoted CD4+ T cells proliferation and Th17 cells differentiation and inhibiting Treg cells differentiation by upregulating RORγt expression and downregulating Foxp3 expression, with increased expression and secretion of IL-17A and IL-22. The proportion of Treg cells was negatively correlated with that of Th17 cells in psoriasis patients. Conclusion: Our results suggest that IL-21 may promote psoriatic inflammation by inducing imbalance in Th17 and Treg cell populations.

Background Bee venom acupuncture has been used in treating patients with shoulder adhesive capsulitis, yet the effectiveness and safety remains unclear. Therefore, this systematic review will aim to assess the effectiveness and safety of bee venom acupuncture for shoulder adhesive capsulitis. Methods Electronic databases including EMBASE, PUBMED, the Cochrane Central Register of Controlled Trials, China National Knowledge Infrastructure, Chinese Scientific Journal Database, Wanfang Database, and Chinese Biomedical Literature Database will be searched for relevant randomized controlled trials from their inception to the search data without language and publication status. Randomized controlled trials involving bee venom acupuncture for treating shoulder adhesive capsulitis will be included. The primary outcome will be pain visual analogue scale, and secondary outcomes include active and passive range of motions, shoulder pain and disability index. Meta-analysis will be conducted using Review Manager software (V.5.3). The results will be presented as risk ratio for dichotomous data, and standardized or weighted mean difference for continuous data. Results The results will be disseminated through a peer-reviewed journal publication. Conclusion These systematic review findings will provide an evidence of bee venom acupuncture for shoulder adhesive capsulitis, and help to inform clinical practitioners and policy-makers in the decision-making. Ethics and dissemination Ethics approval and patient consent are not required as this study is a systematic review based on published articles.

A novel ISAR (inverse synthetic aperture radar) motion compensation approach in conjunction with the phase-derived velocity measurement (PDVM) technique to extract micro-motion feature is presented in this paper. In order to obtain high quality ISAR image, the accurate velocity information provided by PDVM is utilized for target motion compensation. By analyzing proper amount of adjacent Doppler cells around the prominent scatterer in the ISAR image, the impact of other scatterers is effectively reduced for micro-motion extraction. Experiments based on radar measured data are performed to show the effectiveness of the proposed method.