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Electrified railroad has the characteristics of high safety factors, high comfort, large transportation capacity, and less time-consuming, which is an effective means to solve traffic congestion. However, with the rapid development of China’s electrified railroad, harmonic, negative sequence and other power quality problems have also been widely concerned, while more and more regenerative braking energy in the traction power supply system can not be effectively utilized. The input of railroad power regulators makes the power quality problem be solved effectively, this paper studies the control strategy of traditional railroad power regulators. Combined with the actual working conditions of railroad vehicles, the simulation model of traction network, vehicles, and railroad power conditioner is established, and the load characteristics of traction substation are simulated by this model. Secondly, for a domestic substation field collection data processing to obtain the actual train operation load changes, to the battery energy storage device life within the maximum economic returns as the optimization goal, for the peak load reduction judgment threshold and the capacity of the battery energy storage device through the genetic algorithm to process the data of previous years to optimize the design.

Background: This study aimed to evaluate the clinical application of the preoperative prealbumin-to-fibrinogen ratio (PFR) in the clinical diagnosis of hepatocellular carcinoma (HCC) patients and its prognostic value. Methods: The clinical and laboratory data of 269 HCC patients undergoing surgical treatment from January 2012 to January 2017 in Taizhou Hospital were retrospectively analysed. The Cox regression model was used to analyse the correlation between the PFR and other clinicopathological factors in overall survival (OS) and disease-free survival (DFS). Results: Cox regression analysis showed that the PFR (hazard ratio (HR)=2.123; 95% confidence interval (95% CI), 1.271-3.547; P=0.004) was an independent risk factor affecting the OS of HCC patients. Furthermore, a nomogram was built based on these risk factors. The C-index for the OS nomogram was 0.715. Conclusions: Nomograms based on the PFR can be recommended as the correct and actual model to evaluate the prognosis of patients with HCC.

Elevating cut-off voltage is an efficient approach to boost the energy density of Li-ion batteries. However, the failure of conventional carbonate-based electrolyte at high voltage necessitates fundamental understandings of the formation mechanism of the cathode–electrolyte interphase (CEI), especially the contribution from skeleton solvents. In the present work, density functional theory (DFT) calculations reveal the disparity in the productivity and oxidative stability of organic components in the CEI associated with ethylene carbonate (EC), propylene carbonate (PC) and fluoroethylene carbonate (FEC). These two indicators could jointly determine the existence of lithium alkyl carbonates in the CEI, suggested by the species with a m/z of 95 detected with time of flight secondary ion mass spectroscopy (TOF-SIMS). That disparity results in a prominent difference in the capacity retention at high voltage associated with EC, PC and FEC, respectively. These understandings of cyclic carbonates could shed light on bottom-up strategies in electrolyte engineering for the high-voltage electrolyte. [ABSTRACT FROM AUTHOR]

Background: We investigated the prognostic value of the preoperative lymphocyte-to-mononuclear ratio (LMR) and platelet-to-lymphocyte ratio (PLR) in a large cohort of patients with non-small cell lung cancer (NSCLC). Methods: Clinical-pathological data from 507 NSCLC patients at Taizhou Hospital of Zhejiang Province between 2010 and 2016 were retrospectively evaluated. X-tile software was used to assess the optimal cutoff levels for LMR and PLR. Univariate and multivariate Cox regression models were used to assess the prognostic factors. Results: The median follow-up duration after surgical resection was 34.5 months. Patients were stratified into 2 groups by LMR (2.6 and > 2.6) and PLR (179.6 and > 179.6). Our results revealed that lower LMR (HR = 3.163 (1.821-5.493), P = 0.000), age (HR = 2.252 (1.412-3.592), P = 0.001), T stage (HR = 3.749 (2.275-6.179), P = 0.000), N stage (HR = 3.106 (1.967-4.902), P = 0.000), and cut edge (HR = 3.830 (1.077-13.618), P = 0.038) were considered to be independent indicators for overall survival (OS) of NSCLC patients. For disease-free survival (DFS), age, sex, T stage, N stage, LMR and cut edge were verified to be independent prognostic factors in patients with NSCLC. Conclusions: In the study cohort, reduced LMR was a robust independent predictor for both OS and DFS in patients with NSCLC who underwent surgical resection.

As the non-imaging light of optical instruments, stray light has an important impact on normal imaging and data quantification applications. The FY-3D Medium Resolution Spectral Imager (MERSI) operates in a sun-synchronous orbit, with a scanning field of view of 110° and a surface imaging width of more than 2300 km, which can complete two coverage observations of global targets per day with high detection efficiency. According to the characteristics of the operating orbit and large-angle scanning imaging of MERSI, a stray light radiation model of the polar-orbiting spectrometer is constructed, and the design requirements of stray light suppression are proposed. Using the point source transmittance (PST) as the merit function of the stray light analysis method, the instrument was simulated with all stray light suppression optical paths, and the effectiveness of stray light elimination measures was verified using the stray light test. In this paper, the full-link method of "orbital stray light radiation model-system, internal and external simulation design-system analysis and actual test comparison verification" is proposed, and there is a maximum decrease in the system's PST by about 10 times after applying the stray light suppression's optimization design, which can provide a general method for stray light suppression designs for polar-orbit spectral imagers. [ABSTRACT FROM AUTHOR]

Ultrahigh-dimensional grouped data are frequently encountered by biostatisticians working on multi-class categorical problems. To rapidly screen out the null predictors, this paper proposes a quantile-composited feature screening procedure. The new method first transforms the continuous predictor to a Bernoulli variable, by thresholding the predictor at a certain quantile. Consequently, the independence between the response and each predictor is easy to judge, by employing the Pearson chi-square statistic. The newly proposed method has the following salient features: (1) it is robust against high-dimensional heterogeneous data; (2) it is model-free, without specifying any regression structure between the covariate and outcome variable; (3) it enjoys a low computational cost, with the computational complexity controlled at the sample size level. Under some mild conditions, the new method was shown to achieve the sure screening property without imposing any moment condition on the predictors. Numerical studies and real data analyses further confirmed the effectiveness of the new screening procedure. [ABSTRACT FROM AUTHOR]

The side chains on non‐fullerene acceptors (NFAs) can affect greatly the photovoltaic performances of the resulting organic solar cells (OSCs) by regulating the molecular packing and orientation of NFAs. To explore suitable side groups for asymmetric simple NFAs, in this work, we design and synthesize two A‐D1‐A′‐D2‐A type NFAs, NTC‐4Cl, and PhNTC‐4Cl, which own flexible alkyloxy and rigid aryloxy side chains on the A′ cores, respectively. Due to the same molecular backbone (A′: benzotriazole; D1: thiophene; D2: cyclopentadithiophene; A: dichlorodicyanoindanone), NTC‐4Cl and PhNTC‐4Cl have similar absorptions and energy levels. However, the PhNTC‐4Cl‐based OSC gives a higher power conversion efficiency than that of the NTC‐4Cl‐based one (11.09% vs. 10.82%) because PhNTC‐4Cl shows more compact π–π stacking and dominant face‐on orientation, enhancing charge transport and mitigating charge recombination. Therefore, this work provides a new insight into the molecular design of high‐performance NFAs, especially the rational choice of side groups on asymmetric simple NFAs. [ABSTRACT FROM AUTHOR]