The single-stage forward-flyback power factor correction (PFC) converter with quasi-resonant (QR) control is studied in this paper. This converter merges flyback converter and forward converter through a common transformer. Only the flyback sub-converter works when the input voltage is lower than the reflected output voltage while both the flyback sub-converter and the forward sub-converter operate to share the output power in the rest region. The dead zones which exist in the AC input current of traditional forward converter are eliminated and high power factor can be achieved. Two different quasi-resonant (QR) control schemes have been studied. Detailed analysis, optimal design considerations and comparison for these two QR control modes are provided. Finally, two 120W experimental prototypes for LED driver were built up to verify the theoretical analysis.

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The purpose of the study is to investigate the correlation between the expression of C-reactive protein (CRP) and autophagy-related 9B (ATG9B) and pathological features of clear cell renal cell carcinoma (CCRCC) patients. We also intended to explore the effects of manipulated expression of CRP and ATG9B on the apoptosis and cell cycle progression of CCRCC cell line. ATG9B expression in CCRCC tissues and adjacent renal tissues was analyzed by immunohistochemistry (IHC). Gene expression was determined at transcription and translational levels using real-time quantitative PCR (RT-qPCR) and Western blot. The association between CRP/ATG9B expression and clinical-pathological parameters including age, gender, pathological grades, TNM stage and distant metastasis of the patients was assessed by correlation analysis. siRNA and overexpression plasmids construction were used to manipulate the expression of CRP in human CCRCC cell line 786-O. Cell apoptosis and cell cycle progression were determined using flow cytometry (FCM) and Hoechst 33258 staining. CRP expression correlates with ATG9B expression. The expression of CRP and ATG9B are significantly correlated with TNM staging, distant metastasis, and survival time of CCRCC patients. A high-level of CRP indicates a poor overall survival (OS). In addition, CRP expression influences cell cycle and apoptosis of CCRCC cells. The study reveals that CRP might be a CCRCC development promoter. In addition, there is a close relationship between CRP and ATG9B in CCRCC carcinogenesis.

The single-stage flyback power factor correction (PFC) converter is well applied in medium and low power occasion such as adapters or LED drivers. Usually, the flyback PFC converter is preferred to operating in boundary conduction mode (BCM) for achieving high power factor (PF) and high efficiency at the same time. However, the conventional BCM control scheme such as input voltage tracking control or constant on-time control (COT) could not achieve unit PF for the flyback PFC converter. As input voltage increases, the PF and the total harmonic distortion (THD) of flyback converter deteriorate seriously. In this paper, a variable-frequency one-cycle control (VF-OCC) for BCM flyback single-stage PFC converter is presented to achieve unit power factor. Detailed theoretical analysis and design consideration for the VF-OCC are described. At last, two 54W/1.5A laboratory prototypes with two operation strategies have been built up. Experiment results show that the BCM flyback converter with VF-OCC can achieve high PF and low THD over universal input voltage range.

Background We performed a systematic review and meta-analysis to evaluate the efficacy and safety of minimally invasive radical cystectomy (MIRC) versus open radical cystectomy (ORC) for bladder cancer. Methods We searched the EMBASE and MEDLINE databases to identify randomized controlled trials (RCTs) of MIRC versus ORC in the treatment of bladder cancer. Results Eight articles describing nine RCTs (803 patients) were analyzed. No significant differences were found between MIRC and ORC in two oncologic outcomes: the recurrence rate and mortality. Additionally, no significant differences were found in three pathologic outcomes: lymph node yield, positive lymph nodes, and positive surgical margins. With respect to perioperative outcomes, however, MIRC showed a significantly longer operating time, less estimated blood loss, lower blood transfusion rate, shorter time to regular diet, and shorter length of hospital stay than ORC. The incidence of complications was similar between the two techniques. We found no statistically significant differences in the above outcomes between robot-assisted radical cystectomy and ORC or between laparoscopic radical cystectomy and ORC with the exception of the complication rate. Conclusions MIRC is an effective and safe surgical approach in the treatment of bladder cancer. However, a large-scale multicenter RCT is needed to confirm these findings.