Regularization of the Shock Wave Solution to the Riemann Problem for the Relativistic Burgers Equation

The regularization of the shock wave solution to the Riemann problem for the relativistic Burgers equation is considered. For Riemann initial data consisting of a single decreasing jump, we find that the regularization of nonlinear convective term cannot capture the correct shock wave solution. In order to overcome it, we consider a new regularization technique called the observable divergence method introduced by Mohseni and discover that it can capture the correct shock wave solution. In addition, we take the Helmholtz filter for the fully explicit computation

MUSCLE ACTIVATION AND THREE-DIMENSIONAL KINEMATICS OF UPPER EXTREMITY IN SNATCH WEIGHT LIFTING

INTRODUCTION: Previously, there was little weightlifting research focused on biomechanics of the elbow and the shoulder joints (Bartonietz, 1996). Therefore, the purposes of this study were to evaluate the kinematics of upper extremity on sagittal plane during 1st pull, transition from the 1st to the 2nd pull, 2nd pull, turnover under the barbell, catch phase, and rising from the squat position phases of snatch weight lifting and to examine upper-limb muscles activity during snatch weight lifting. The EMG signals were analyzed using the normalized linear envelopes

(Dithio­benzoato-κ2 S,S′)[hydridotris(pyrazol-1-yl-κN 2)borato](triphenyl­phosphine-κP)ruthenium(II)

Reaction of [Ru(Tp)Cl(PPh3)2] (Tp = hydridotrispyrazolyl­borate) with ammonium dithio­benzoate in methanol leads to the formation of the title compound, [Ru(C9H10BN6)(C7H5S2)(C18H15P)]. In the crystal structure, the Ru atom is coordinated by three N atoms of the Tp ligand, one P atom of the triphenyl­phosphine ligand and the two S atoms of the dithio­benzoate ligand within a slightly distorted octa­hedron. The Ru—S bonds are slightly different [2.321 (1) and 2.396 (1) Å] and the average N—Ru—N angle is 86.31°

Off-diagonal low-rank preconditioner for difficult PageRank problems

PageRank problem is the cornerstone of Google search engine and is usually stated as solving a huge linear system. Moreover, when the damping factor approaches 1, the spectrum properties of this system deteriorate rapidly and this system becomes difficult to solve. In this paper, we demonstrate that the coefficient matrix of this system can be transferred into a block form by partitioning its rows into special sets. In particular, the off-diagonal part of the block coefficient matrix can be compressed by a simple low-rank factorization, which can be beneficial for solving the PageRank problem. Hence, a matrix partition method is proposed to discover the special sets of rows for supporting the low rank factorization. Then a preconditioner based on the low-rank factorization is proposed for solving difficult PageRank problems. Numerical experiments are presented to support the discussions and to illustrate the effectiveness of the proposed methods. (C) 2018 Elsevier B.V. All rights reserved

Inhibitory effects of armepavine against hepatic fibrosis in rats

Activation of hepatic stellate cells (HSCs) plays a crucial role in liver fibrogenesis. armepavine (Arm, C19H23O3N), an active compound from Nelumbo nucifera, has been shown to exert immunosuppressive effects on T lymphocytes and on lupus nephritic mice. The aim of this study was to investigate whether Arm could exert anti-hepatic fibrogenic effects in vitro and in vivo. A cell line of rat HSCs (HSC-T6) was stimulated with tumor necrosis factor-α (TNF-α) or lipopolysaccharide (LPS) to evaluate the inhibitory effects of Arm. An in vivo therapeutic study was conducted in bile duct-ligated (BDL) rats. BDL rats were given Arm (3 or 10 mg/kg) by gavage twice daily for 3 weeks starting from the onset of BDL. Liver sections were taken for fibrosis scoring, immuno-fluorescence staining and quantitative real-time mRNA measurements. In vitro, Arm (1-10 μM) concentration-dependently attenuated TNF-α- and LPS-stimulated α-SMA protein expression and AP-1 activation by HSC-T6 cells without adverse cytotoxicity. Arm also suppressed TNF-α-induced collagen collagen deposition, NFκB activation and MAPK (p38, ERK1/2, and JNK) phosphorylations. In vivo, Arm treatment significantly reduced plasma AST and ALT levels, hepatic α-SMA expression and collagen contents, and fibrosis scores of BDL rats as compared with vehicle treatment. Moreover, Arm attenuated the mRNA expression levels of col 1α2, TGF-β1, TIMP-1, ICAM-1, iNOS, and IL-6 genes, but up-regulated metallothionein genes. Our study results showed that Arm exerted both in vitro and in vivo antifibrotic effects in rats, possibly through anti-NF-κB activation pathways

Bioequivalence Evaluation of Two Formulations of Celecoxib 200 mg Capsules in Healthy volunteers by using a validated LC/MS/MS method

The bioequivalence study to compare a new formulation of celecoxib to its reference formulation was designed as an open-label, randomized, single-dose, two-way crossover, comparative bioavailability study by using a validated LC/MS/MS method. In order to determine the plasma concentrations of celecoxib, a sensitive LC/MS/MS method was developed. The method was validated to possess adequate specificity, linearity, precision, accuracy and stability. The linearity of calibration curve was assessed between the concentration intervals (5–2000 ng/mL) with a correlation coefficient over 0.999. Regarding pharmacokinetic investigation, the mean celecoxib AUC0-t values from the test and reference drug formulations were 7360.44 ± 1714.14 h•ng/mL and 7267.48 ± 2077.68 h•ng/mL, respectively, and the corresponding AUC0-∞ values were 8197.45 ± 2040.31 h•ng/mL and 7905.54 ± 2286.12 h•ng/mL, respectively. The Cmax of the test and reference drugs was 705.30 ± 290.63 ng/mL and 703.86 ± 329.91 ng/mL, respectively, and the corresponding Tmax was 3.4 ± 1.6 h and 2.9 ± 1.4 h. Lastly, the T1/2 values of the test and reference drugs were 13.9 ± 7.9 h and 12.9 ± 7.7 h, respectively. The 90% confidence intervals for AUC0-t, AUC0-∞, and Cmax were 97.00-108.85, 98.01-112.09, and 93.20-116.13, respectively, satisfying the bioequivalence criteria of 80-125% range. In conclusion, these results demonstrated that the bioequivalence of two formulations of celecoxib was established successfully by utilizing present developed LC/MS/MS method

Methyl­ene bis­(dithio­benzoate)

In the title compound, C15H12S4, two phenyl­dithio­carboxyl­ate units are linked through a methyl­ene C atom on a twofold rotation axis. The central S—CH2—S angle of 116.9 (5)° is significantly larger than the ideal tetra­hedral value. The dihedral angle formed by the two phenyl rings is 68.2 (1)°. The refined Flack parameter of 0.2 (3) does not permit unambiguous determination of the absolute structure

Diagnostic Value of Autoantibodies in Lung Cancer: a Systematic Review and Meta-Analysis

Background/Aims: Recently, many studies have demonstrated that various tumor-associated autoantibodies have been detected in early stages of lung cancer. Therefore, we conducted a meta-analysis to comprehensively evaluate available evidence on the diagnostic value of autoantibodies against tumor-associated antigens in lung cancer. Methods: We systematically searched PubMed, Scopus, Web of Science and other databases through 23 March 2018. Study quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2. We used the bivariate mixed-effect models to calculate pooled values of sensitivity, specificity, positive likelihood ratios, negative likelihood ratios, diagnostic odds ratios and associated 95% confidence intervals. Summary receiver operating characteristic (SROC) curves were used to summarize overall test performance. Deek’s funnel plot was used to detect publication bias. Results: Review of 468 candidate articles identified fifty-three articles with a total of 11,515 patients for qualitative review and meta-analysis. Pooled sensitivity, specificity and area under the SROC curve were as follows for tumor-associated autoantibodies against the following proteins: p53, 0.19, 0.98, 0.82; NY-ESO-1, 0.17, 0.98, 0.90; Survivin, 0.19, 0.99, 0.96; c-myc, 0.14, 0.98, 0.45; Cyclin B1, 0.18, 0.98, 0.91; GBU4-5, 0.07, 0.98, 0.91; CAGE, 0.14, 0.98, 0.90; p16, 0.08, 0.97, 0.91; SOX2, 0.14, 0.99, 0.93; and HuD, 0.17, 0.99, 0.82. Conclusion: Each tumor-associated autoantibody on its own showed excellent diagnostic specificity for lung cancer but inadequate sensitivity. Our results suggest that combinations or panels of tumor-associated autoantibodies may provide better sensitivity for diagnosing lung cancer, and the diagnostic accuracy of tumor-associated autoantibodies should be validated in more studies