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The utility of geotechnical centrifuge tests depends on how correctly they predict the physical and mechanical behaviour of concrete. In this study, a model concrete material that consisted of α-gypsum plaster, fine silica sand, and water was developed. An orthogonal test design was used to evaluate the effect of the mix proportion on the model concrete performance. The physical (i.e., flowability and bleeding rate) and mechanical (i.e., compressive and flexural strength) characteristics were considered as indices. Various mix ratios resulted in remarkable relative contributions to model concrete performance, and each raw material dosage exhibited positive or negative synergy. The water–plaster ratio (W/P) and aggregate–plaster ratio (A/P) strongly influenced the mechanical and physical characteristics, respectively. Multiple linear regression analysis (MLRA) was carried out to determine a forecast model for various small-scale test demands. Finally, the applicability and outlines of the presented forecasting method in proportioning design were evaluated by typical use of model concrete in small-scale model tests. [ABSTRACT FROM AUTHOR]

• An efficient implementation of DGLBM is given in detail. Performance test shows our special implementation is faster than the record in the previous publications. • Generally, high-order DGLBM can give better computing efficiency than LBM if higher accuracy is required in simulations. • The p -type refinement in DGLBM can increase the computing efficiency, but excessive p -type refinement on very coarse meshes may not obtain consistent convergence in under-resolved DNS. • The DNS of fully developed turbulent pipe flow is successfully performed by DGLBM with only D3Q19 lattice and BGK model, which indicates DGLBM is more stable and accurate than LBM especially in curved boundary cases. The application of finite element method in solving the lattice Boltzmann equation has been successfully demonstrated by many researchers. However, the computation cost of these methods is much higher than the standard lattice Boltzmann method. In this paper, an efficient implementation of nodal discontinuous Galerkin lattice Boltzmann method is presented. It relies on a simplified nodal discontinuous Galerkin formulation, which makes full use of the possible sparse property of elemental matrices in quadrangles and hexahedrons. Some key points of its implementation in the program are also discussed. Performance tests confirm the superior efficiency of the current program, which exceeds the record of previous researchers. The accuracy of the current method is investigated and compared with the standard lattice Boltzmann method. The high-order discretization can give similar accuracy with lower number of grid points and computational time and the efficiency of the present method is sometimes higher than standard lattice Boltzmann method. Direct numerical simulations of several incompressible turbulence benchmark cases are performed. The present method also shows better accuracy and stability especially in the turbulent pipe flow simulations. [ABSTRACT FROM AUTHOR]

Fe isotopes have been applied to the petrogenesis of ore deposits. However, the behavior of iron isotopes in the mineralization of porphyry-skarn deposits is still poorly understood. In this study, we report the Fe isotopes of ore mineral separations (magnetite, pyrite, chalcopyrite and pyrrhotite) from two different skarn deposits, i.e., the Tonglvshan Cu-Fe skarn deposit developed in an oxidized hydrothermal system and the Anqing Cu skarn deposit developed in a reduced hydrothermal system. In both deposits, the Fe isotopes of calculated equilibrium fluids are lighter than those of the intrusions responsible for the skarn and porphyry mineralization, corroborating the "light-Fe fluid" hypothesis. Interestingly, chalcopyrite in the oxidized-Tonglvshan skarn deposit has lighter Fe than chalcopyrite in the reduced-Anqing skarn deposit, which is best understood as the result of the prior precipitation of magnetite (heavy Fe) from the ore fluid in the oxidized-Tonglvshan systems and the prior precipitation of pyrrhotite (light Fe) from the ore fluid in the reduced-Anqing system. The δ56Fe for pyrite shows an inverse correlation with δ56Fe of magnetite in the Tonglvshan. In both deposits, the Fe isotope fractionation between chalcopyrite and pyrite is offset from the equilibrium line at 350 °C and lies between the FeS-chalcopyrite equilibrium line and pyrite-chalcopyrite equilibrium line at 350 °C. These observations are consistent with the FeS pathway towards pyrite formation. That is, Fe isotopes fractionation during pyrite formation depends on a path from the initial FeS-fluid equilibrium towards the pyrite-fluid equilibrium due to the increasing extent of Fe isotopic exchange with fluids. This finding, together with the data from other deposits, allows us to propose that the pathway effect of pyrite formation in the Porphyry-skarn deposit mineralization is the dominant mechanism that controls Fe isotope characteristics. [ABSTRACT FROM AUTHOR]

Background: Perioperative opioid use for pain control has been found to be associated with side effects and adverse prognosis. In this study, we hypothesized that paravertebral block could reduce the consumption of opioids during pancreatic resection surgery., Methods: We conducted a prospective, randomized trial. Patients with resectable pancreatic cancer were randomly assigned to one of the two groups: those who received bilateral paravertebral block combined with general anesthesia [bilateral paravertebral blockade (PTB) group] or those who received only general anesthesia (Control group). The primary endpoint was the perioperative consumption of opioids (sufentanil and remifentanil). The main secondary endpoints were pain scores, complications, and serum cytokine levels., Results: A total of 153 patients were enrolled in the study and 119 cases were analyzed. Compared to the control group, patients in PTB patients had significantly lower perioperative (30.81 vs. 56.17 µg), and intraoperative (9.58 vs. 33.67 µg) doses of sufentanil (both p  < 0.001). Numerical rating scale scores of pain were comparable between the two groups. No statistical differences in complications were detected., Conclusion: Bilateral paravertebral block combined with general anesthesia reduced the perioperative consumption of opioids by 45%., Registration Number: ChiCTR1800020291 (available on http://www.chictr.org.cn/)., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2022 Han, Dai, Shi, Zhang, Xia, Ji, Yu, Bian and Xu.)

Emerging resistance to antimicrobials and the lack of new antibiotic drug candidates underscore the need for optimization of current diagnostics and therapies to diminish the evolution and spread of multidrug resistance. As the antibiotic resistance status of a bacterial pathogen is defined by its genome, resistance profiling by applying next-generation sequencing (NGS) technologies may in the future accomplish pathogen identification, prompt initiation of targeted individualized treatment, and the implementation of optimized infection control measures. In this study, qualitative RNA sequencing was used to identify key genetic determinants of antibiotic resistance in 135 clinical Pseudomonas aeruginosa isolates from diverse geographic and infection site origins. By applying transcriptome-wide association studies, adaptive variations associated with resistance to the antibiotic classes fluoroquinolones, aminoglycosides, and β-lactams were identified. Besides potential novel biomarkers with a direct correlation to resistance, global patterns of phenotype-associated gene expression and sequence variations were identified by predictive machine learning approaches. Our research serves to establish genotype-based molecular diagnostic tools for the identification of the current resistance profiles of bacterial pathogens and paves the way for faster diagnostics for more efficient, targeted treatment strategies to also mitigate the future potential for resistance evolution., (Copyright © 2016, American Society for Microbiology. All Rights Reserved.)