Machine Learning for Prediction of Sudden Cardiac Death in Heart Failure Patients With Low Left Ventricular Ejection Fraction: Study Protocol for a Retrospective Multicentre Registry in China

Introduction: Left ventricular ejection fraction (LVEF) ≤35%, as current significant implantable cardioverter-defibrillator (ICD) indication for primary prevention of sudden cardiac death (SCD) in heart failure (HF) patients, has been widely recognised to be inefficient. Improvement of patient selection for low LVEF (≤35%) is needed to optimise deployment of ICD. Most of the existing prediction models are not appropriate to identify ICD candidates at high risk of SCD in HF patients with low LVEF. Compared with traditional statistical analysis, machine learning (ML) can employ computer algorithms to identify patterns in large datasets, analyse rules automatically and build both linear and non-linear models in order to make data-driven predictions. This study is aimed to develop and validate new models using ML to improve the prediction of SCD in HF patients with low LVEF. Methods and analysis: We will conduct a retroprospective, multicentre, observational registry of Chinese HF patients with low LVEF. The HF patients with LVEF ≤35% after optimised medication at least 3 months will be enrolled in this study. The primary endpoints are all-cause death and SCD. The secondary endpoints are malignant arrhythmia, sudden cardiac arrest, cardiopulmonary resuscitation and rehospitalisation due to HF. The baseline demographic, clinical, biological, electrophysiological, social and psychological variables will be collected. Both ML and traditional multivariable Cox proportional hazards regression models will be developed and compared in the prediction of SCD. Moreover, the ML model will be validated in a prospective study. Ethics and dissemination: The study protocol has been approved by the Ethics Committee of the First Affiliated Hospital of Nanjing Medical University (2017-SR-06). All results of this study will be published in international peer-reviewed journals and presented at relevant conferences

Predictive value of the resistance of the probe to pass through the lesion in the diagnosis of peripheral pulmonary lesions using radial probe endobronchial ultrasound with a guide sheath

BackgroundTransbronchial lung biopsy guided by radial probe endobronchial ultrasonography with a guide sheath (EBUS-GS-TBLB) is becoming a significant approach for diagnosing peripheral pulmonary lesions (PPLs). We aimed to explore the clinical value of the resistance of the probe to pass through the lesion in the diagnosis of PPLs when performing EBUS-GS-TBLB, and to determine the optimum number of EBUS-GS-TBLB.MethodsWe performed a prospective, single-center study of 126 consecutive patients who underwent EBUS-GS-TBLB for solid and positive-bronchus-sign PPLs where the probe was located within the lesion from September 2019 to May 2022. The classification of probe resistance for each lesion was carried out by two bronchoscopists independently, and the final result depended on the bronchoscopist responsible for the procedures. The primary endpoint was the diagnostic yield according with the resistance pattern. The secondary endpoints were the optimum number of EBUS-GS-TBLB and factors affecting diagnostic yield. Procedural complications were also recorded.ResultsThe total diagnostic yield of EBUS-GS-TBLB was 77.8%, including 83.8% malignant and 67.4% benign diseases (P=0.033). Probe resistance type II displayed the highest diagnostic yield (87.5%), followed by type III (81.0%) and type I (61.1%). A significant difference between the diagnostic yield of malignant and benign diseases was detected in type II (P = 0.008), whereas others did not. Although most of the malignant PPLs with a definitive diagnosis using EBUS-GS-TBLB in type II or type III could be diagnosed in the first biopsy, the fourth biopsy contributed the most sufficient biopsy samples. In contrast, considerably limited tissue specimens could be obtained for each biopsy in type I. The inter-observer agreement of the two blinded bronchoscopists for the classification of probe resistance was excellent (κ = 0.84).ConclusionThe probe resistance is a useful predictive factor for successful EBUS-GS-TBLB diagnosis of solid and positive-bronchus-sign PPLs where the probe was located within the lesion. Four serial biopsies are appropriate for both probe resistance type II and type III, and additional diagnostic procedures are needed for type I

Study On Photovoltaic Modules On Greenhouse Roof For Energy And Strawberry Production

The aim of this study was to investigate the effect of PV modules mounted on top of a greenhouse, on the growth of strawberries and microclimate conditions as well as to estimate the generated energy. In this study, two greenhouses with the same volume were established. One greenhouse was equipped with the opaque photovoltaic (OPV) modules which accounted for 25.9% of the roof area, and the other was equipped with the semi-transparent photovoltaic (STPV) modules which accounted for 20% of the roof area. The maximum annual power generation of OPV and STPV modules was 880 and 388 kWh with 30° tilt angle, respectively, by simulating different tilt angles. The temperature under the OPV and STPV modules was 2.9 and 1.1 °C lower than the unshaded part in the greenhouses, respectively, at noon in clear weather, and had little effect on relative humidity. The photosynthetically active radiation (PAR) under OPV and STPV modules was reduced by 43.5% and 31.7%, respectively, under the PE film greenhouse. The contents of soluble solids in strawberries in OPV and STPV greenhouses were 16.4 and 15.7 mg/g respectively, which were higher than those in unshaded samples. The quality and yield of the strawberry samples under the shade of OPV were better than those of the STPV shade

Poly(Heptazine Imide) Ligand Exchange Enables Remarkable Low Catalyst Loadings in Heterogeneous Metallaphotocatalysis

The development of heterogeneous metallaphotocatalysis is of great interest for sustainable organic synthesis. The rational design and controllable preparation of well-defined (site-isolated) metal/photo bifunctional solid catalysts to meet such goals remain a critical challenge. Herein, we demonstrate the incorporation of privileged homogeneous bipyridyl-based Ni-catalysts into highly ordered and crystalline potassium poly(heptazine imide) (K-PHI). A variety of PHI-supported cationic bipyridyl-based Ni catalysts (LnNi-PHI) have been prepared and fully characterized by various techniques, including NMR, ICP-OES, XPS, HAADF-STEM, and XAS. The LnNi-PHI catalysts exhibit exceptional chemical stability and recyclability in diverse C−P, C−S, C−O, and C−N cross-coupling reactions. The proximity and cooperativity effects in LnNi-PHI significantly enhance the photo/Ni dual catalytic activity, thus resulting in low catalyst loadings and high turnover numbers