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It is unclear whether associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) can be performed in hepatitis B virus-related hepatocellular carcinoma (HCC) patients with cirrhosis. We explored the efficacy of ALPPS in HCC patients.Data of 54 patients who underwent ALPPS between August 2014 and July 2020 at three centers were collected. Adverse factors affecting their prognosis were analyzed and subsequently compared with 184 patients who underwent transcatheter arterial chemoembolization (TACE).Overall survival rates of the ALPPS group at 1, 3, and 5 years were 70.6%, 38.4%, and 31.7%, respectively; corresponding disease-free survival rates were 50.5%, 22.4%, and 19.2%, respectively. The ALPPS group had a significantly greater long-term survival rate than the TACE group (before propensity score matching, P 0.001; after propensity score matching, P = 0.002). Multivariate analysis demonstrated that multifocal lesions (P = 0.018) and macroscopic vascular invasion (P = 0.001) were prognostic factors for HCC patients who underwent ALPPS. After the propensity score matching, the multifocal lesions (P = 0.031), macroscopic vascular invasion (P = 0.003), and treatment type (ALPPS/TACE) (P = 0.026) were the factors adversely affecting the prognosis of HCC patients.ALPPS was feasible in hepatitis B virus-related HCC patients with cirrhosis and resulted in better survival than TACE.

The major concern in the aviation industry is the flight safety. Although great effort has been put into the development of material and system reliability, the failure cases of fatal accidents still occur nowadays. Due to the complexity of the aviation system and the interaction among the failure components, it is difficult to do the failure analysis of the related equipment. This study focused on surveying the failure cases in aviation, which were extracted from failure analysis journals, including Engineering Failure Analysis and Case studies in Engineering Failure Analysis, in order to obtain the failure sensitive factors or failure sensitive parts. The analytical results showed that among the failure cases the fatigue failure is the largest in number of occurrence. The most failed components are the disk, blade, landing gear, bearing, and fastener. The frequently failed materials are steel, aluminum alloy, superalloy and titanium alloy. Therefore, in order to assure the safety in aviation, more attention should be paid to the fatigue failures.

The outbreak of a novel coronavirus (COVID-19) generated an outbreak of public opinions in the Chinese Sina-microblog. To help in designing effective communication strategies during a major public health emergency, we propose a multiple-information susceptible-discussing-immune (M-SDI) model in order to understand the patterns of key information propagation on social networks. We develop the M-SDI model, based on the public discussion quantity and take into account of the behavior that users may re-enter another related topic or Weibo after discussing one. Data fitting using the real data of COVID-19 public opinion obtained from Chinese Sina-microblog can parameterize the model to make accurate prediction of the public opinion trend until the next major news item occurs. The reproduction ratio has fallen from 1.7769 and maintained around 0.97, which reflects the peak of public opinion has passed but it will continue for a period of time.

This paper considers an explicit continuation method and the trust-region updating strategy for the unconstrained optimization problem. Moreover, in order to improve its computational efficiency and robustness, the new method uses the switching preconditioning technique. In the well-conditioned phase, the new method uses the L-BFGS method as the preconditioning technique in order to improve its computational efficiency. Otherwise, the new method uses the inverse of the Hessian matrix as the pre-conditioner in order to improve its robustness. Numerical results also show that the new method is more robust and faster than the traditional optimization method such as the trust-region method and the line search method. The computational time of the new method is about one percent of that of the trust-region method (the subroutine fminunc.m of the MATLAB2019a environment is set by the trust-region method) or one fifth of that of the line search method (fminunc.m is set by the quasi-Newton method) for the large-scale problem. Finally, the global convergence analysis of the new method is also given.

BACKGROUND Laparoscopic cholecystectomy (LC) combined with laparoscopic common bile duct (CBD) exploration (LCBDE) is one of the main treatments for choledocholithiasis with CBD diameter of larger than 10 mm. However, for patients with small CBD (CBD diameter ≤ 8 mm), endoscopic sphincterotomy remains the preferred treatment at present, but it also has some drawbacks associated with a series of complications, such as pancreatitis, hemorrhage, cholangitis, and duodenal perforation. To date, few studies have been reported that support the feasibility and safety of LCBDE for choledocholithiasis with small CBD. AIM To investigate the feasibility and safety of LCBDE for choledocholithiasis with small CBD. METHODS A total of 257 patients without acute cholangitis who underwent LC + LCBDE for cholecystolithiasis from January 2013 to December 2018 in one institution were reviewed. The clinical data were retrospectively collected and analyzed. According to whether the diameter of CBD was larger than 8 mm, 257 patients were divided into large CBD group (n = 146) and small CBD group (n = 111). Propensity score matching (1:1) was performed to adjust for clinical differences. The demographics, intraoperative data, short-term outcomes, and long-term follow-up outcomes for the patients were recorded and compared. RESULTS In total, 257 patients who underwent successful LC + LCBDE were enrolled in the study, 146 had large CBD and 111 had small CBD. The median follow-up period was 39 (14-86) mo. For small CBD patients, the median CBD diameter was 0.6 cm (0.2-2.0 cm), the mean operating time was 107.2 ± 28.3 min, and the postoperative bile leak rate, rate of residual CBD stones (CBDS), CBDS recurrence rate, and CBD stenosis rate were 5.41% (6/111), 3.60% (4/111), 1.80% (2/111), and 0% (0/111), respectively; the mean postoperative hospital stay was 7.4 ± 3.6 d. For large CBD patients, the median common bile duct diameter was 1.0 cm (0.3-3.0 cm), the mean operating time was 115.7 ± 32.0 min, and the postoperative bile leak rate, rate of residual CBDS, CBDS recurrence rate, and CBD stenosis rate were 5.41% (9/146), 1.37% (2/146), 6.85% (10/146), and 0% (0/146), respectively; the mean postoperative hospital stay was 7.7 ± 2.7 d. After propensity score matching, 184 patients remained, and all preoperative covariates except diameter of CBD stones were balanced. Postoperative bile leak occurred in 11 patients overall (5.98%), and no difference was found between the small CBD group (4.35%, 4/92) and the large CBD group (7.61%, 7/92). The incidence of CBDS recurrence did not differ significantly between the small CBD group (2.17%, 2/92) and the large CBD group (6.52%, 6/92). CONCLUSION LC + LCBDE is safe and feasible for choledocholithiasis patients with small CBD and did not increase the postoperative bile leak rate compared with chole-docholithiasis patients with large CBD.

By using Monte Carlo simulations, we investigated a triangle double-layer graphene nanoisland with mixed-spin (3/2, 2) configuration. We focused on the effects of crystal-fields, exchange couplings, longitudinal magnetic fields, and temperature on the magnetic properties of the system. Various curves of magnetization, susceptibility, and internal energy as a function of temperature were obtained. We plotted the phase diagrams of blocking temperature in the different parameter planes. We found that increasing |Jab/JZ|,Jbb/JZ, and h/JZ or weakening |Db/JZ| is beneficial to improving the TB/JZ, but the TB/JZ is very insensitive to changes in the Da/JZ and Jaa/JZ. In addition, it is worth noting that the system can exhibit abundant multiple-loops hysteresis behaviors for certain physical parameters, such as triple, quadruple, quintuple, septuple hysteresis loops.

For nonlinear equations, the homotopy methods (continuation methods) are popular in engineering fields since their convergence regions are large and they are quite reliable to find a solution. The disadvantage of the classical homotopy methods is that their computational time is heavy since they need to solve many auxiliary nonlinear systems during the intermediate continuation processes. In order to overcome this shortcoming, we consider the special explicit continuation Newton method with the residual trust-region time-stepping scheme for this problem. According to our numerical experiments, the new method is more robust and faster to find the required solution of the real-world problem than the traditional optimization method (the built-in subroutine fsolve.m of the MATLAB environment) and the homotopy continuation methods(HOMPACK90 and NAClab). Furthermore, we analyze the global convergence and the local superlinear convergence of the new method.

The nonlinear optimization problem with linear constraints has many applications in engineering fields such as the visual-inertial navigation and localization of an unmanned aerial vehicle maintaining the horizontal flight. In order to solve this practical problem efficiently, this paper constructs a continuation method with the trusty time-stepping scheme for the linearly equality-constrained optimization problem at every sampling time. At every iteration, the new method only solves a system of linear equations other than the traditional optimization method such as the sequential quadratic programming (SQP) method, which needs to solve a quadratic programming subproblem. Consequently, the new method can save much more computational time than SQP. Numerical results show that the new method works well for this problem and its consumed time is about one fifth of that of SQP (the built-in subroutine fmincon.m of the MATLAB2018a environment) or that of the traditional dynamical method (the built-in subroutine ode15s.m of the MATLAB2018a environment). Furthermore, we also give the global convergence analysis of the new method.