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Objective: This study aimed to evaluate methotrexate efficacy in patients with Crohn’s disease (CD) and ulcerative colitis (UC), and identify predictors of surgery for patients who were initially treated with methotrexate monotherapy.Design: We performed a retrospective analysis of 34,860 patients with inflammatory bowel disease (IBD) in the IBD Bioresource (United Kingdom) prior to 9 November 2021. Logistic regression was used to identify factors associated with methotrexate efficacy. The data were randomly stratified into training and testing sets (7:3). Nomograms were developed based on Cox regression analysis outcomes. The predictive accuracy and discriminative ability were determined using the concordance index (C-index) and calibration curves.Results: Overall, 1,042 patients (CD: 791, UC: 251) were included. Independent factors associated with effective methotrexate monotherapy were younger age at diagnosis, latest therapy period, exclusive upper gastrointestinal tract disease (for CD), and longer duration between diagnosis and methotrexate initiation (for UC). For CD, predictors in the nomogram were gender, treatment era, tolerance, lesion site, perianal involvement, disease behaviour, and biologics requirements (C-index: 0.711 and 0.732 for training and validation cohorts, respectively). For UC, the factors were age at diagnosis and sex (C-index: 0.784 and 0.690 for training and validation cohorts, respectively). Calibration curves demonstrated good agreement between predictions and actual observations.

The tectonic setting of the Jiamusi–Khanka Massif in the eastern sector of the Central Asian Orogenic Belt (CAOB) in NE China is still highly controversial. This review considers all existing data to evaluate the origin of the Jiamusi–Khanka Massif. The Precambrian basement in the Jiamusi–Khanka Massif is dominated by the Neoproterozoic orthogneisses (898–891 and 757–751 Ma), the Mashan Complex (peak metamorphism at 530–500 Ma), and syntectonically deformed early Palaeozoic granitoids (530–484 Ma) related to the metamorphism of the Mashan Complex. The Mashan Complex reveals a clockwise orogen-style P–T path with peak conditions of 850–870°C/8–9 kbar followed by isothermal decompression. It was intruded by syn- (530–500 Ma) and post-tectonic (490–476 Ma) granitic rocks. The Jiamusi–Khanka Massif cannot be directly derived from the North China, South China, or Tarim cratons. Instead, it may have originated in the Siberian Craton and formed once part of the Altai-Sayan and Baikal orogens at ~500 Ma. For the Jiamusi Massif, we developed a plate tectonic model, and relate the final granulite facies metamorphism to slab break-off after consumption of a branch of the Palaeo-Asian Ocean.

ObjectiveTo investigate and compare the clinical features of drug-induced liver injury (DILI) and primary biliary cirrhosis (PBC). MethodsA total of 116 PBC patients and 124 DILI patients who were diagnosed in Shengjing Hospital of China Medical University from January 2005 to December 2013 were enrolled, and clinical features, laboratory indices, and the results of liver biopsy were compared between the two groups. The t-test or Nemenyi rank sum test was applied for comparison of continuous data between the two groups, and the chi-square test was applied for comparison of categorical data between the two groups. ResultsThere were significant differences in age of onset and gender composition between the two groups(both P＜0.05). The serological markers (except albumin), immunological indicators (IgG, IgM, and IgA), and positive rate of autoantibodies (except SMA) showed significant differences between the two groups (all P＜0.05). The histological appearances of PBC were hepatocyte edema (30 patients), inflammatory cell infiltration around the bile duct (29 patients), and atypical hyperplasia of the small bile duct (28 patients), and those of DILI were hepatocyte steatosis (15 patients) and spotty necrosis and loss of hepatocytes (14 patients). ConclusionDILI and PBC are different in the aspects of laboratory tests and pathological examinations, which has a certain guiding significance in differential diagnosis in clinical practice.

Red bed soft rock exhibits poor physical and mechanical properties and certain creep characteristics, which cause continuous deformation of tunnels and underground engineering structures during operation. The rock mass at the bottom of a railway tunnel in Sichuan Province is mudstone of the Penglaizhen Formation of the Upper Jurassic. It has a thin to medium-thick layered structure. Moreover, the rock formation is nearly horizontal. In this paper, the shear creep test and deep learning are employed to study the creep characteristics of gentle dip red bed mudstone.The results indicate that the red bed mudstone in the tunnel site exhibits medium-low creep characteristics. When the stress level is relatively low, the rate of the creep deformation gradually reduces with time, and when it reaches a certain time, the deformation no longer increases, and the final deformation tends to a stable value. Conversely, when the stress level is relatively high, although the rate of the creep deformation gradually reduces as the time increases, it remains unchanged when it reduces to a certain value. At the initial stage of creep, the deformation of each grade is evident; at the middle stage, the deformation is slow; and at the later stage, the deformation remains unchanged, that is, it enters the stable creep stage after a rapid decay in creep rate. The long-term strength of red bed mudstone in the tunnel site is low, which easily causes continuous deformation of the surrounding rock of tunnels under the action of high ground stress. According to the long-term deformation monitoring data at the bottom of the tunnel, combined with 20 groups of red bed mudstone creep parameter samples and the upper arch deformation data of the tunnel numerical model, the deep learning inverse analysis model of the creep parameter of rock mass is established based on the deep learning algorithm. Finally, we obtain the creep parameter of the red bed mudstone via inverse analysis. The research results provide a basis for engineering structure design and long-term deformation prediction of red bed mudstone strata in this area.

Complex geological environment and difficulties in operation and maintenance of mountain tunnels result in a lot of damage during the operation period of mountain tunnels. Therefore, the risk assessment and reinforcement technologies for complex mountain tunnels during the operation period need to be developed and improved. As a result, in this paper, the research on safety influence factors and their weights during the operation period of complex mountain tunnels was conducted based on Fuzzy Comprehensive Evaluation (FCE) and Analytic Hierarchy Process (AHP), the fuzzy set of weights for risk influencing factors during the operation period of complex mountain tunnels was established, the membership functions of factors at the index level were determined, the comprehensive evaluation matrix of tunnel risks was obtained, and the fuzzy comprehensive evaluation method for risks of complex mountain tunnels was proposed. This method has been verified in the Jinjishan Tunnel, and its analysis results are credible. In addition, corresponding risk prevention and control measures were put forward based on the evaluation results, and they provided guidance and reference for similar projects.

Salvia miltiorrhiza (SM) is mainly used for the treatment of coronary heart disease in china and it also represses inflammation, but the mechanism is not well known. This study aimed to investigate the effects of SM powder for injection on the expressions of transcription factor T-bet (T-bet) and tumor necrosis factor α (TNFα) in the experimental colitis in mice. Mice were grouped and treated with SM powder for injection at the time of colonic instillation of trinitrobenzene sulfonic acid (TNBS). Expression studies were performed by real-time polymerase chain reaction (PCR), western blot (WB) and immunohistochemistry (IHC), and histology studies were performed by hematoxylin and eosin stain (H&E). The survival of mice was also monitored. The expressions of TNFα in the colon, T-bet messenger ribonucleic acid (mRNA) and T-bet protein in the spleen decreased in the groups treated with SM powder for injection. The inflamed colonic lesions were relieved and the survival of mice also increased in the treated groups. SM powder for injection repressed the expressions of T-bet and TNFα in the experimental colitis in mice, which could relieve the inflamed colonic lesions and elevate the survival of mice. Key words: Salvia miltiorrhiza, T-bet, tumor necrosis factor α, colitis, mice, inflammatory bowel disease, Crohn’s disease, ulcerative colitis.

A self-consistent creep damage constitutive model and a finite element model have been developed for nickel-base directionally solidified superalloys. Grain degradation and grain boundary voiding are considered. The model parameters are determined from the creep test data of a single crystal and a directionally solidified superalloy with a special crystallographic orientation. The numerical analysis shows that the modeled creep damage behaviors of nickel-base directionally solidified superalloys with different crystallographic orientations are in good agreement with the experimental data.

We present a method of calculating the interaction between two particles in a single chain and between two chains in different structures in a non-polar liquid by using the equivalent conductivity plate concept. With this method, we obtain the quasi-static shear force-strain relationships and yield stresses of single-chain, 2D close-packed, rectangular and 3D BCT structures. By comparing the yield stresses with that of a single chain, we draw the conclusions that the interactions between chains in 2D close-packed and BCT structures enhance their yield stresses and that the enhancement becomes more significant as the number of chains increases, whereas the interactions between chains in a 2D rectangular structure weaken its yield stress. These results reveal the significant and distinct contribution of the structure of an electrorheological fluid to its yield stress.

Based on [1], the stress structures of the smooth region and shear lip of the specimens have been investigated in the paper. The characteristics of the stress structure in the smooth region have been found that the variable z can separated out; the stresses in the midsection can be obtained by the plane strain FEM results or HRR structure modified by the stress triaxiality. The effects of load level and thickness on the stress structure can be reflected by the distribution of CTOD along the thickness direction. The obtained expressions of the stresses are very simple and visualized. The analyses of the stress structure in the shear lip show that the stresses can be obtained by different methods of interpolation to a certain precise degree.

In the present paper, three dimensional analyses of some general constraint parameters and fracture parameters near the crack tip. of Mode I CT specimens in two different thicknesses are carried out by employing ADINA program. The results reveal that the constraints along the thickness direction are obviously separated into two parts: the keeping similar high constraint field (Z1) and rapid reducing constraints one (Z2). The two fields are experimentally confiremed to correspond to the smooth region and the shear lip on the fracture face respectively. So the three dimensional stress structure of Mode I specimens can be derived through discussing the two fields respectively. The distribution of the Crack Tip Opening Displacement (CTOD) along the thickness direction and the three dimensional distribution of the void growth ratio (Vg) near the crack tip are also obtained. The two fracture parameters are in similar trends along the thickness direction, and both of them can reflect the effect of thickness and that of the loading level to a certain degree.

A unified damage and fracture model, the combinatory work density model, which is suitable for either non-cracked body or cracked body has been suggested[t−7]. In the present paper, the deformation and fracture of the two kinds of tensile spceimen and TPB specimen made of 40Cr steel have been simulated by using the new model together with the large elastic-plastic deformation finite element method. The results give a good picture of the whole deformation and fracture processes of the specimens in experiments; especially, the results on the TPB specimen can be used to obtain the relationship between load and displacement at the loading pointP-Δ, and between crack extension and displacement at the loading point Δa-Δ, the resistance curveJ R -Δa and the fracture toughnessJ 1C . All the results are in remarkable agreement with those obtained by experiments. Therefore the model suggested here can be used to simulate crack initiation and propagation in non-cracked body and fracture initiation and crack stable propagation in cracked body.