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This work investigates the role of flexibility and resonant excitation on the deformation mechanism and aerodynamic performance of flapping wings. A hummingbird-inspired wing (HIW) is considered and designed to have a bone-like stiffener made of carbon fibre/epoxy (CF/E) composite attached to a membrane made of carbon nanotubes/polypropylene (CNTs/PP) nanocomposite representing the flexible part of the natural wing. The designed HIW model is analysed through fluid-structure interaction simulations performed at frequencies near and at resonant frequency. It is found that HIW generates desired bending and twisting deformations that are coupled. These deformation mechanisms are studied in detail with the help of time-varying deflections and bending-twisting angles. Further, the simultaneous effect of these parameters on the aerodynamic performance of the wing is also investigated. It is observed that the coupled nature of bending and twisting deformations is critical in enhancing the aerodynamic performance of flapping wings. In addition to that, the resonance generates higher amplitude of desired structural deformations that further enhances thrust as well as lift generation capability of the wing. The underlying mechanism for this is also explained by studying the flow around the deflected surface of the wing. Compared to off-resonant frequencies, vorticity and pressures are substantially higher for the wing at resonance. A physical model of HIW is realised using CNTs/PP and CF/E composites to perform experimental wing motion analysis and to validate the computational results. In conclusion, the present study provides a basis to design efficient biomimetic flapping wings for micro aerial vehicles (MAVs) by exploring flexibility and resonant excitation.

Radiomics involves the extraction of information from medical images that are not visible to the human eye. There is evidence that these features can be used for treatment stratification and outcome prediction. However, there is much discussion about the reproducibility of results between different studies. This paper studies the reproducibility of CT texture features used in radiomics, comparing two feature extraction implementations, namely the MATLAB toolkit and Pyradiomics, when applied to independent datasets of CT scans of patients: (i) the open access RIDER dataset containing a set of repeat CT scans taken 15 min apart for 31 patients (RIDER Scan 1 and Scan 2, respectively) treated for lung cancer; and (ii) the open access HN1 dataset containing 137 patients treated for head and neck cancer. Gross tumor volume (GTV), manually outlined by an experienced observer available on both datasets, was used. The 43 common radiomics features available in MATLAB and Pyradiomics were calculated using two intensity-level quantization methods with and without an intensity threshold. Cases were ranked for each feature for all combinations of quantization parameters, and the Spearman’s rank coefficient, rs, calculated. Reproducibility was defined when a highly correlated feature in the RIDER dataset also correlated highly in the HN1 dataset, and vice versa. A total of 29 out of the 43 reported stable features were found to be highly reproducible between MATLAB and Pyradiomics implementations, having a consistently high correlation in rank ordering for RIDER Scan 1 and RIDER Scan 2 (rs > 0.8). 18/43 reported features were common in the RIDER and HN1 datasets, suggesting they may be agnostic to disease site. Useful radiomics features should be selected based on reproducibility. This study identified a set of features that meet this requirement and validated the methodology for evaluating reproducibility between datasets.

OBJECTIVE: To distinguish clinical features, safety and efficiency of endoscopic retrograde cholangiopancreatography (ERCP) in patients after bilioenteric anstomosis based on retrospectively analyzed clinical data and endoscopy procedures. METHODS: Data extracted from patients after bilioenteric anstomosis due to biliary disease treated with ERCP from January 2005 to December 2021 in the Department of Gastroenterology, Peking University Third Hospital were retrospectively analyzed. Clinical data and endoscopic pictures were reevaluated and analyzed. The patients were divided into three groups, including the patients with choledochoduodenostomy (CDD), Roux-en-Y hepaticojejunostomy (RYHJ) and Whipple. Differences between ERCP success and failure were conducted. RESULTS: In the study, 89 cases with 132 ERCP procedures were involved, 9-80 years old, median 57 years old, containing 4 CDD, 30 RYHJ, 54 Whipple and 1 bile duct ileocecal anastomosis patients; The time between ERCP and surgery were 30 (1-40), 2.75 (0.5-14), 2 (0.3-19), and 10 years, respectively; The time between surgery and symptom were 240 (3-360), 12 (1-156), 22 (0-216), and 60 months, respectively. Fifty percent of CDD could succeed only under local anaesthesia, RYHJ (96.7%) and Whipple (100.0%) needed under general anaesthesia (P < 0.001). Successful first entry rates of CDD, RYHJ and Whipple were 100.0%, 40.0% and 77.8%, respectively. After changing the endoscopy type, successful entry rate could increase to 43.3% of RYHJ and 83.3% of Whipple. The successful entry rate of different anastomotic methods was significant (P < 0.001). The cannulation success rates of CDD, RYHJ and Whipple were 100.0%, 53.8% and 86.7% respectively, with significant difference between the groups (P=0.031). ERCP success rates of CDD, RYHJ and Whipple were 100.0%, 33.3% and 78.8% respectively, with significant difference between the groups (P < 0.001). Complications were found in 23.9% (21/88) patients, including infection (14.8%), pancreatitis (9.2%), bleeding (3.4%), and perforation (2.3%) ranked by incidence. Causes of ERCP in post bilioenteric anstomosis were anastomotic stenosis (50.0%, benign 39.3%, malignant 10.7%), choledocholithiasis (37.5%) and reflux cholangitis (12.5%). Anastomotic method was the only predicting factor of ERCP success in patients after bilioenteric anstomosis (OR=7, 95%CI: 2.591-18.912, P < 0.001). CONCLUSION: ERCP in post bilioenteric anstomosis patients with gastrointestinal reconstruction need general anaesthe-sia, with good safety and efficiency. The successful rate of RYHJ was significantly lower than Whipple. Anastomotic method was the only predicting factor of ERCP success.

A myopic patient with self-reported photorefractive keratectomy 9 years ago requested small incision lenticule extraction (SMILE) as retreatment. The presence of interface bubbles while creating a corneal cap of the right eye revealed that the previous refractive surgery was laser in situ keratomileusis (LASIK). Therefore, the SMILE procedure was resumed in the right eye, but flap-lift LASIK was performed in the left eye. Postoperative follow-up showed that the vision in both eyes reached the preoperative best corrected level. SMILE may be a potential option for refractive regression after LASIK.1例9年前因近视眼行“双眼准分子激光角膜切削术”男性患者因屈光不正（近视眼）行飞秒激光小切口角膜基质透镜取出术（SMILE）。术中切削角膜帽时出现气泡散逸，明确既往手术方式为准分子激光原位角膜磨镶术（LASIK），右眼继续完成SMILE，左眼改为原位掀角膜瓣LASIK。术后随访双眼裸眼视力均达到术前最佳矫正视力。希望本病例为临床开展角膜屈光手术二次补矫手术提供经验和借鉴。.

We studied the effects and mechanisms of action of conophylline in different concentrations in the original in vitro model of myocardial fibrosis (treatment of cardiac fibroblasts isolated form the hearts of newborn rats with angiotensin II). Viability, collagen content, and expression of related protein in cardiac fibroblasts were assessed using the MTT-test, Sircol assay, and Western blotting, respectively. Conophylline markedly protected the cultured cells against the development of angiotensin II-induced fibrosis, which was seen from reduced viability of fibroblasts, decreased collagen content, and down-regulation of the expression of α-smooth muscle actin (α-SMA). Conophylline did not affect the TGF-β pathway altered by angiotensin II, but markedly decreased the level of bone morphogenetic protein-4 (BMP4) enhanced by angiotensin II and BMP4 itself. Conophylline produced no effect on phosphorylation of α-SMA and Smad homologue-1/5/8, the classic BMP4 downstream pathway elements, but reduced the level of c-Jun N-terminal kinase (JNK) elevated by BMP4. Conophylline did not inhibit the development of myocardial fibrosis in the presence of JNK activator anisomycin. Thus, conophylline inhibited angiotensin II-provoked myocardial fibrosis via the BMP4/JNK pathway.

Deep U-Net Neural Network from the paper "Approximating Three-dimensional (3-D) Transport of Atmospheric Pollutants via Deep Learning" in Pytorch is built for replacing and accelerating the transport procedure in the chemical transport models. The dataset consisted of meteorological field, emission inventory, and concentrations of pollutant. Meteorological field was estimated by the Weather Research and Forecasting (WRF) model with the initial conditions and observation dataset from the National Centers for Environmental Prediction (NCEP). Emission inventory was derived from the Multi-resolution Emission Inventory for China (MEIC v1.3, 0.25° × 0.25°, 2016,http://www.meicmodel.org) and interpolated to the required 12 km *12 km horizontal resolution. A 3-D CTM numerical model of the Community Multiscale Air Quality (CMAQ) (https://github.com/USEPA/CMAQ/tree/5.3.1) was selected to simulate the concentration evolution with the meteorological field and emission inventory, as well as the benchmark for computation efficiency comparison for the deep learning surrogate.The retrieved training and validation datasets are too large (>1T) to be uploaded for share. Anyone who is interested in them is welcomed to contact the corresponding author for a point-to-point transfer. Full Changelog: https://github.com/junzheXu/DL_3-DTransport/commits/v0.0.0

Tumour necrosis factor inhibitors (TNFis) are commonly used for treating psoriatic diseases; however, the risk of infection while receiving TNFis remains uncertain. The aim of this study was to investigate the infection risk in patients with psoriatic disease receiving TNFis. A prospectively registered systematic literature search was conducted in Medline (PubMed), Cochrane Central Register of Controlled Trials (CENTRAL), EMBASE and the ClinicalTrials.gov databases from inception to December 31, 2021. We included double-blind randomized controlled trials that compared TNFis or other biologics with placebo in adults with psoriasis or psoriatic arthritis. The primary outcomes included overall and serious infection risks, and secondary outcomes included upper respiratory infections and nasopharyngitis risks. The risk ratio of the dichotomous outcome was calculated using the Mantel-Haenszel method with random effects, and heterogeneity was assessed using Cochran's Q statistic and quantified using the I-squared statistic. A total of 48 studies with 15 464 patients with psoriatic diseases were included. The meta-analysis demonstrated a slightly increased overall infection risk (risk ratio = 1.09; 95% confidence interval, 1.02-1.15) but not serious infection risk (risk ratio = 0.95; 95% confidence interval, 0.61-1.49) among patients receiving TNFis. There were also no increased risks of upper respiratory infections (risk ratio = 1.10; 95% confidence interval, 0.94-1.28) or nasopharyngitis (risk ratio = 1.14; 95% confidence interval, 1.00-1.30). In subgroup analyses using the fixed effects model, only etanercept and certolizumab pegol were, respectively, associated with an increased risk of overall infection (RR = 1.14, 95% CI, 1.03-1.27) and upper respiratory infections (RR = 1.42, 95% CI, 1.02-1.98). In conclusion, evidence to date suggests an increased overall infection risk that is generally tolerable in patients with psoriatic diseases receiving TNFis. There are no increased risks of serious infections, upper respiratory infections or nasopharyngitis.