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Based on the bidirectional evolutionary structural optimization (BESO) method, the present article proposes an optimization method for a thermal structure involving design-dependent convective boundaries. Because the BESO method is incapable of keeping track of convection boundaries, virtual elements are introduced to assist in identifying the convection boundaries of the structure. In order to solve the difficult issue of element assignment under a design-dependent convection boundary, label matrixes are employed to modify the heat transfer matrix and the equivalent temperature load vector of elements over topology iterations. Additionally, the optimization objective is set to minimize the maximum temperature of the structure in order to deal with the objective reasonableness, and the p-norm method is then used to fit the objective function to calculate sensitivity. Finally, several cases, including 2D and 3D structures under various heat transfer boundary conditions, are provided to illustrate the effectiveness and good convergence of the proposed method.

Although concomitant nonalcoholic steatohepatitis (NASH) is common in chronic hepatitis B (CHB), the impact of viral factors on NASH and the outcome of CHB patients concomitant with NASH remain unclear. We aimed to investigate the outcomes of NASH in CHB patients receiving antiviral treatment.In the post-hoc analysis of a multicenter trial, naïve CHB patients receiving 72-week entecavir treatment were enrolled. We evaluated the biochemical, viral and histopathological responses of these patients. The histopathological features of NASH were also evaluated, using paired liver biopsies at baseline and week 72.A total of 1000 CHB patients were finally enrolled for analysis, with 18.2% of whom fulfilling the criteria of NASH. A total of 727 patients completed entecavir antiviral treatment and received the second biopsy. Serum HBeAg loss, HBeAg seroconversion and HBV-DNA undetectable rates were similar between patients with or without NASH (P0.05). Among patients with NASH, the hepatic steatosis, ballooning, lobular inflammation scores and fibrosis stages all improved during follow-up (all P0.001), 46% (63/136) achieved NASH resolution. Patients with baseline body mass index (BMI) ≥ 23 kg/mLower BMI and weight reduction but not virologic factors determine NASH resolution in CHB. The value of weight management in CHB patients during antiviral treatment deserves further evaluation.

The distribution and evolution of air in airliner cabins is an important basis for the study of cabin thermal environment and pollutant propagation. Due to the complex heat and mass transfer problems caused by forced and natural convection in a large-scale space, the accurate prediction of air distribution in airliner cabins still faces huge challenges. This study takes the cabin of the Airbus A320 as the research object. The accurate numerical simulation of the flow and heat transfer process in an airliner cabin under mixing ventilation mode was carried out using the Hybrid Thermal Lattice Boltzmann Method (HTLBM) combined with GPU (Graphics Processing Unit) acceleration technology, and the influence of human thermal plumes on air distribution and evolution characteristics in an airliner cabin was analyzed. The research shows that the human thermal plume changes the air distribution in the passenger cabin. The thermal plume slows down the jet attenuation, increases the energy exchange in the area near the passengers, and offsets the jet trajectory. The airflow self-locking effect is easier to form in the passenger breathing area, which increases the time for the flow field to develop into the steady state. The influence of human thermal plumes on the airflow distribution in the passenger cabin cannot be ignored.

Chronic hepatitis B (CHB) and liver fibrosis are associated with a high risk of hepatocellular carcinoma (HCC) development. We assessed whether entecavir (ETV) plus Biejia-Ruangan compound (BRC), an anti-fibrotic traditional Chinese medicine, can further reduce the risk of HCC in treatment-naïve Chinese patients with CHB and an Ishak fibrosis score of ≥3 points derived from our parent double-blind randomized placebo-controlled trial.After a 72-week comparison between ETV+BRC and ETV+placebo treatment, participants were eligible to enter an open-label treatment phase and were followed up every 6 months. The primary [secondary] endpoints were the incidence of HCC [liver-related deaths, non-HCC events, and non-liver-related deaths]. Modified intention-to-treat (mITT), intention-to-treat (ITT), and per-protocol (PP) populations were defined for the time-to-event analysis.A total of 1,000 patients were recruited; the median age was 42.0 years; 69.9% were male and 58.3% were HBeAg positive. In the mITT population, the 7-year cumulative incidence of HCC [liver-related deaths] was 4.7% [0.2%] for ETV+BRC, which was significantly lower than 9.3% [2.2%] for ETV monotherapy (p = 0.008 [p = 0.030]). Notably, ETV+BRC treatment yielded a lower incidence of HCC in those who did not achieve regression of fibrosis at week 72 than ETV monotherapy (p = 0.018). There were no differences in the other 2 secondary endpoints or safety profiles between the groups. Multivariable Cox proportional regression analysis, including the treatment allocation as a parameter, also demonstrated that ETV+BRC treatment was associated with a reduced incidence of HCC. The ITT and PP analyses showed consistent results.ETV plus BRC combination treatment could further reduce the risk of HCC and liver-related deaths in patients with CHB and advanced fibrosis or cirrhosis, which may have important clinical implications for HCC prevention.Patients with chronic hepatitis B virus infection are at an increased risk of developing liver cancer (specifically hepatocellular carcinoma [HCC]). While there are effective antiviral treatments that can suppress the virus in chronically infected patients, the risk of HCC remains. Herein, we show that adding a traditional Chinese medicine called Biejia-Ruangan compound to an antiviral reduced the risk of HCC in patients with chronic hepatitis B.

Objective. To explore the clinical value of the specific plasma cell detection and specific T lymphocyte detection test in diagnosing hypersensitivity caused by antituberculosis drugs. Methods. A total of 266 patients with pulmonary tuberculosis who developed hypersensitivity during the treatment of primary pulmonary tuberculosis in our hospital and 266 patients without hypersensitivity during the treatment of pulmonary tuberculosis in our hospital were selected as the control group. The admission time is from January 2013 to June 2020. The specific plasma cell test and specific T lymphocyte test were used as the criteria to determine which drugs induced hypersensitivity, and the diagnostic value of these two methods in the diagnosis of hypersensitivity induced by four first-line antituberculosis drugs (isoniazid (INH), ethambutol (EMB), rifampicin (RFP), and pyrazinamide (PZA)) was analyzed. Results. The sensitivity of the specific plasma cell test in the diagnosis of hypersensitivity induced by INH, EMB, RFP, and PZA was 63.42%, 51.20%, 47.81%, and 56.37%, respectively, and the specificity was 95.33%, 99.87%, 96.52%, and 99.99%, respectively. The sensitivity of the specific T lymphocyte test in the diagnosis of hypersensitivity induced by INH, EMB, RFP, and PZA was 66.47%, 52.88%, 49.91%, and 58.54%, respectively, and the specificity was 97.28%, 99.99%, 98.38%, and 100.00%, respectively. Conclusion. The specific plasma cell test and specific T lymphocyte test have high specificity in the diagnosis of hypersensitivity caused by antituberculosis drugs, and the specific T lymphocyte test is better than the specific plasma cell test. It is of great significance to guide the clinical application of antituberculosis drugs.

Background The clinical manifestations and factors associated with the severity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections outside of Wuhan are not clearly understood. Methods All laboratory-confirmed cases with SARS-Cov-2 infection who were hospitalized and monitored in Guangzhou Eighth People’s Hospital were recruited from January 20 to February 10. Results A total of 275 patients were included in this study. The median patient age was 49 years, and 63.6% had exposure to Wuhan. The median virus incubation period was 6 days. Fever (70.5%) and dry cough (56.0%) were the most common symptoms. A decreased albumin level was found in 51.3% of patients, lymphopenia in 33.5%, and pneumonia based on chest computed tomography in 86%. Approximately 16% of patients (n = 45) had severe disease, and there were no deaths. Compared with patients with nonsevere disease, those with severe disease were older, had a higher frequency of coexisting conditions and pneumonia, and had a shorter incubation period (all P Conclusions Most of the patients infected with SARS-CoV-2 in Guangzhou, China are not severe cases and patients with older age, male, and decreased albumin level were more likely to develop into severe ones.

This paper deals with the surface thermochemical effects on TPS-coupled aerothermodynamics in hypersonic Martian gas flow. An interface condition with finite-rate thermochemistry was established to balance the three-dimensional Navier-Stokes solver and TPS thermal response solver, and a series of coupled simulations of chemical non-equilibrium aerothermodynamics and structure heat transfer with various surface catalycities were performed for hypersonic Mars entries. The analysis of surface thermochemistry reveals that the surface chemical reactions have great contribution to aerodynamic heating, and the temperature-dependence of finite-rate catalysis highly influences the evolution of the coupling aerodynamic heating in the coupling process. For fixed free stream parameters with proper catalytic excitation energy, a “leap” phenomenon of the TPS-coupled heat flux with the coupling time appears in the initial stage of the coupling process, due to the strong thermochemical effects on the TPS surface.

The anisotropic micro-structure of fiber will lead to the macroscopic anisotropic properties of fiber reinforced composites in both heat transfer and mechanical strength. However, few experimental studies have be made on the anisotropic heat transfer properties of fiber reinforced composites. In this study, the anisotropic thermal conductivities of two-dimensional (2D) plain woven and twill woven carbon-fiber/epoxy composites are measured at different temperature with the one-dimensional (1D) steady-state method, transient plane source (TPS) method and transient hot wire method, respectively. The out-of-plane thermal conductivity and in-plane thermal conductivity at the temperature ranging from −45 °C to 160 °C are obtained and comparisons are made among the three methods. The results show that all the three methods can be used to measure the anisotropic thermal conductivity of fiber/epoxy woven composites. Both the out-of-plane thermal conductivity and in-plane thermal conductivity of carbon-fiber/epoxy woven composites increase with temperature, and the in-plane thermal conductivity is approximately four times as high as the out-of-plane thermal conductivity for the plain woven composites. Compared with the results of 1D steady-state method, the max deviations of TPS method and hot wire method are 18.1% and 17.1%, respectively. The sources of error that leading to the deviations are also discussed.

Background: HBeAg-positive chronic infection is a unique phase of chronic hepatitis B virus (HBV) infection. Current guidelines advise against starting antiviral treatment for HBeAg-positive chronic hepatitis B virus (HBV) infection patients, some data suggest treating such patients may reduce the risk of hepatocellular carcinoma. We aimed to explore whether these patients can have evident histological liver injury (EHLI), and develop a non-invasive model for identifying EHLI in such patients. Method: We assessed whether HBeAg-positive chronic HBV infection patients can have EHLI defined by Ishak fibrosis stage ≥3 and/or histologic activity index ≥ 9 in a prospective multicenter study. Logistic and Lasso regression was used to select the optimal predictors. We used Akaike information criterion, discrimination improvement, net reclassification improvement to develop and validate models predicting EHLI risk in training cohort and two external validation cohorts. Findings: Of these 336 patients met the inclusion criteria, 181(54%) were HBeAg-positive chronic HBV infection, of whom 60 patients (33%) had EHLI, the proportion of significant fibrosis was higher than that of significant inflammation (33% vs. 8%, P

Hypersonic aircrafts and aero-engine combustion chambers both generate non-equilibrium and high-enthalpy flows and bring complex material-relied heat convection performance. The convective heating prediction is difficult due to unknown surface thermal state, leading to poor usability of wall temperature correlation method (WTCM). This paper aims at improving WTCM for convective heating prediction in chemically reacting flows through coupling computation of catalysis on thermal protection materials. Modified WTCM for chemically reacting flows accounts for two distinct physical events driven by temperature gradient and species reaction, which follow the Fourier’s and Fick’s laws, respectively. Preliminary validation testing demonstrates the feasibility of the modified WTCM to rapidly evaluate aerodynamic heating with limited deviation. The current research provides essential technical support for the evaluation and design of hypersonic aircrafts and aero-engine combustion chambers.

Hypersonic carbon dioxide reacting gas-surface interaction occurs on the heat shield of high-speed Mars entry capsules, which has great influences on the heat transfer characteristics. Based on hypersonic reacting flow solver with complex surface thermochemistry, the hypersonic chemical non-equilibrium flow with oxygen/carbon gas mixture was numerically simulated, and the interaction between non-equilibrium flow and surface reactions was numerically analyzed to reveal the mechanism of aerodynamic heating from surface thermochemistry. Numerical results of catalytic effects show that the near-wall thermochemical behaviors are essentially dominated by the near-wall diffusion and chemical reactions. Various surface reactions alter the flow structure in the boundary layer, and generate different aerodynamic heating patterns. Results from ablating simulations indicate that the ablating surface can induce additional near-wall diffusion and injection energy though their influence on the thermal boundary layer structure is neglectably small. The modeling of reacting gas-surface interaction can be of benefit to promoting the fidelity and precision of aerodynamic heating with complex surface thermochemistry.

The Mars Science Laboratory (MSL) entry capsule has been designed as a lifting entry for sufficient deceleration and precise landing performance. This paper presents the static aerodynamics analysis of the MSL capsule in the hypersonic entry process for exploration mission to Mars. Hypersonic static coefficients were derived from fully three-dimensional computational fluid dynamics solutions with a specified effective specific heat ratio on a typical trajectory state. Aerodynamic performance analysis ascertains the trim characteristics and static stability of the capsule with respect to the center of gravity (CG) location. Analysis results obtained show that CG location determines the trim characteristics and the static stability, and certain CG radial and axial shift alters the lifting entry performance, so that proper aerodynamic configuration and inner equipment layout is needed for CG adjustment to satisfy the static aerodynamics requirements.

Background Chronic hepatitis B (CHB) can progress to cirrhosis, hepatocellular carcinoma (HCC) and ultimately liver-related death. Although oral antiviral therapy for patients with CHB reduces the risk of such complications, once cirrhosis is established, the benefits of antiviral therapy are not robustly demonstrated. According to traditional Chinese medicine (TCM), some Chinese herbal medicines promote blood circulation and soften hard masses, and therefore they may block and reverse hepatic fibrosis. The aim of this study is to evaluate the effects of TCM tablets of the compound biejia ruangan (RGT) administered for fibrosis, and entecavir (ETV), on the development of HCC in patients with CHB or hepatitis B virus (HBV)-related compensated cirrhosis. Methods/design This multicenter, centrally randomized, double-blind, placebo-controlled, parallel-group study is planned to complete within 5 years. For the study, 1,000 with CHB or HBV-related compensated cirrhosis are randomly assigned in a 1:1 ratio to a treatment group (0.5 mg ETV once daily; 2 g RGT three times daily) or a control group (0.5 mg ETV once daily; 2 g RGT dummy agent three times daily). The primary end points are the development of HCC and liver-related death. Secondary end points include disease progression and overall survival. Discussion Although antiviral therapy can achieve sustained suppression of HBV replication, thereby preventing cirrhosis, patients with CHB treated with nucleos(t)ide analogs (NUCs) retain a higher risk for HCC compared with patients with inactive disease. Although previous clinical trials with RGT have confirmed the efficacy of blocking and reversing hepatic fibrosis in patients with CHB or compensated cirrhosis, the long-term risk for HCC or disease progression in these patients treated with combination of RGT and NUCs compared with NUCs alone is unclear. Therefore, it is necessary to investigate the effects of the RGT blockade and reversal of hepatic fibrosis on the development of HCC in patients with CHB or HBV-related compensated cirrhosis in large, prospective, multicenter, double-blind, randomized, controlled trials in China. Trial registration ClinicalTrials.gov Identifier: NCT01965418. Date registered: 17 October 2013