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Tetrandrine (Tet), a traditional Chinese herbal medicine extract, exhibits anti‐cancer effect on many types of cancer. Nonetheless, the action mechanism of Tet in gastric cancer (GC) is still largely unclear. In the current study, proliferation, invasion, and migration of the BGC‐823 and MKN‐45 cells were effectively suppressed by Tet treatment in a dose‐dependent manner. Moreover, Tet suppressed expression of the proliferation‐associated protein PCNA, the interstitial cell phenotype N‐cadherin, and the extracellular matrix‐associated MMP‐2 and MMP‐9 in BGC‐823 and MKN‐45 cells in a dose‐dependent manner. PI3K/AKT/mTOR, a cancer promoting signaling, was inactivated by Tet in a dose‐dependent manner in BGC‐823 and MKN‐45 cells. Furthermore, our results demonstrated that the inhibition of Tet to PCNA, N‐cadherin, MMP‐2, and MMP‐9 expression was partly rescuedby AKT inhibitor or mTOR inhibitor. In animal experiments, tumor growth was inhibited by Tet administration in a dose‐dependent manner. In conclusion, the current data indicated that Tet had a critical effect on inhibiting BGC‐823 and MKN‐45 cells proliferation, migration, invasion, and tumor growth via regulating PI3K/AKT/mTOR signaling pathway, suggesting that Tet might be a potential treatment for GC. [ABSTRACT FROM AUTHOR]

A nonlinear integral sliding-mode control (NISMC) scheme is proposed for second order nonlinear systems. The new control scheme is characterized by a nonlinear integral sliding manifold which inherits the desired properties of the integral sliding manifold, such as robustness to system external disturbance. In particular, compared with four kinds of sliding mode control (SMC), the proposed control scheme is able to provide better transient performances. Furthermore, the proposed scheme ensures the zero steady-state error in the presence of a constant disturbance or an asymptotically constant disturbance is proved by Lyapunov stability theory and LaSalle invariance principle. Finally, both the theoretical analysis and simulation examples demonstrate the validity of the proposed scheme.

Background. Fecal microbiota transplantation (FMT) is a current research hotspot, with a surge in the output of publications over the past decade. This study dedicates to the exploration of the research status and highlights significant themes and future trends in FMT research with the aid of bibliometric analysis. Methods. FMT publications from 2012 to 2021 were retrieved on August 12, 2022, using the SCI-Expanded of Web of Science (WoS). The Bibliometrix in R program, Microsoft Office Excel, VOSviewer, and CiteSpace were utilized for bibliometrics and visual analysis, revealing the main publications, journals, countries, agencies, authors, and keywords distribution in FMT research. Results. There were 2,931 papers included. FMT research presented a growing trend from 2012 to 2021. The countries with the most publications and contributions in FMT area were China and the United States. The high-yield institutions were Harvard University, Udice French Research Universities, and the University of California System. The primary authors were Nieuwdorp Max, Allegretti Jessica R, and Kassam Zain. Frontiers in Microbiology and Science were the top-ranked journals in publications and total citations, respectively. The important topics primarily included FMT-related mechanisms and the usage of FMT in Clostridium difficile infection (CDI), inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), metabolic disease, neurological disorders, and psychiatric disorders. Future research would primarily concentrate on neurological disorders, chemotherapy and immunotherapy for malignant tumors, and FMT-related consensus and guidelines. Conclusion. With the help of bibliometric analysis, we were able to obtain the understanding of the status and trends of global FMT-related research. The field of FMT is undergoing tremendous progress, and our findings can guide clinical researchers' and practitioners' future work in the rapidly evolving field of FMT. [ABSTRACT FROM AUTHOR]

The production performance of waterflood reservoirs with years of production is severely challenged by high water cuts and extensive water channels. Among IOR/EOR methods, weak gel injection is particularly effective in improving the water displacement efficiency and oil recovery. The visualized microscopic oil displacement experiments were designed to comprehensively investigate the weak gel mechanisms in porous media and the numerical simulations coupling equations characterizing weak gel viscosity induced dynamics were implemented to understand its planar and vertical block and movement behaviors at the field scale. From experiments, the residual oil of initial water flooding mainly exists in the form of cluster, column, dead end, and membranous, and it mainly exists in the form of cluster and dead end in subsequent water flooding stage following weak gel injection. The porous flow mechanism of weak gel includes the preferential plugging of large channels, the integral and staged transport of weak gel, and the residual oil flow along pore walls in weak gel displacement. The profile-control mechanism of weak gel is as follows: weak gel selectively enters the large channels, weak gel blocks large channels and forces subsequent water flow to change direction, weak gel uses viscoelastic bulk motion to form negative pressure oil absorption, and the oil droplets converge to form an oil stream, respectively. The numerical simulation indicates that weak gel can effectively reduce the water-oil mobility ratio, preferentially block the high permeability layer and the large pore channels, divert the subsequent water to flood the low permeability layer, and improve the water injection swept efficiency. It is found numerically that a weak gel system is able to flow forward under high-pressure differences in the subsequent water flooding, which can further improve oil displacement efficiency. Unlike the conventional profile-control methods, weak gels make it possible to displace the bypassed oil in the deep inter-well regions with significant potential to enhance oil recovery. [ABSTRACT FROM AUTHOR]

Herein, thermochromic superhydrophobic coatings (TSCs) with different colors are prepared, and their surface wettabilities and optical properties are studied. The TSC coating maintains its surface superhydrophobicity even after a series of mechanical damage (sandpaper abrasion, gravel impact, and knife scratching), chemical corrosion, ultraviolet aging, and environmental temperature changes. Contaminants on the surface of the coating sre easily washed by water droplets. The TSC has a reversible color function with a critical discoloration temperature (Tc) approximately in the range 28–31 °C. In winter, the ambient temperature (Ta) is lower than Tc, and the TSC is dark and absorbs more solar energy. Although in summer, Ta > Ta, the TSC is light and reflects more solar energy. The sunlight exposure test shows that the surface temperature of the thermochromic pigment/polydimethylsiloxane (TP/PDMS) coating in winter is only 0.9 °C lower than that of the carbon black/PDMS (CB/PDMS) coating, whereas in summer, the surface temperature of the TP/PDMS coating is only 6.2 °C higher than that of TiO2/PDMS coating. Energy consumption simulation results show that the TP/PDMS coating decreases the total annual energy consumption in North China by 13.74% compared with the traditional white cooling coating. [ABSTRACT FROM AUTHOR]

This paper investigates the planar wide-frequency vibration characteristics of heavy-load radial tires with a large aspect ratio. A proposed tire model with a piecewise flexible beam on an elastic foundation is investigated and validated using experimental modal analysis and theoretical modeling method. The reproducibility of frequency response functions below 400 Hz is discussed. The experimental modal analysis particularly assesses the coupling of features across the circumferential and cross-sectional directions of heavy-load radial tire carcass. Piecewise circumferential modal characteristics were investigated experimentally, leading to the suggestion of a piecewise flexible beam on an elastic tire foundation. Using a genetic algorithm (GA), the structural parameters EI, ρ A , and kr and damping coefficients η and cr for the proposed tire model are identified, and the piecewise transfer functions and the planar transfer functions for a heavy-load radial tire are compared with planar hammer test. Experimental and theoretical results show the following: (1) the sectional vibration characteristics for a heavy-load radial tire with a large aspect ratio result from the cross-sectional vibration of the tire carcass; (2) the piecewise transfer function is mainly influenced by the circumferential vibration of the flexible carcass, and this is consistent with a model where a flexible beam is placed on an elastic tire foundation; (3) the analytical transfer functions calculated for the proposed tire model, drawing on the identified structural parameters and damping coefficients, agree well with the experimental results. [ABSTRACT FROM AUTHOR]

It is important to determine the reasonable injection and production rates in the development of multilayer tight oil reservoir with water flooding treatment. Based on the INSIM (interconnection-based numeric simulation model), a connected network model, a new method is designed to evaluate the water injection efficiency of different layers in water flooding reservoirs and to optimize the injection-production system to produce more oil. Based on the types of sedimentary facies and corresponding injection-production data, the interwell connections are divided into four major categories (middle channel, channel edge, middle channel bar, and channel bar edge) and twelve subclasses. This classification standard of interwell connections could help to significantly improve the accuracy of judging the dominant flow path without constructing a complicated geological model. The interaction of interwells such as injection-production correlation and water injection efficiency could be revealed by simulating the production performance and computing the layer dividing coefficient and well dividing coefficient. A numerical example is used to validate this method by comparing results from FrontSim and this method, and the computational efficiency of this method is several dozen times faster than that of the traditional numerical simulation. This method is applied to quickly optimize the production schedule of a tight oil reservoir with the water flooding treatment, that is, the water injection rate of multilayer reservoirs could be optimized subtly by the injection efficiency of different layers, and the target of producing more oil with lower water cut could be achieved. [ABSTRACT FROM AUTHOR]

Considering an aircraft threatened by an interceptor, one of the effective penetration strategies is to release a Defender from the aircraft to confront the interceptor. In this case, the aircraft, the Defender, and the interceptor constitute the three-body guidance relationship, and the cooperation of the aircraft and its Defender to achieve the best tactical effects turns into a concerned problem. This paper studies the triangle interception guidance problem via the finite-time theory. The paper presents linear system Input-Output Finite-Time Stabilization (IO-FTS) method. The sufficient conditions of the linear system, being IO-FTS, under Finite-Time Boundedness (FTB) constraint are proposed, by which the state feedback controllers design method is obtained, via Linear Matrix Inequalities (LMIs). The triangle interception guidance problems are studied in three different cases, where the proposed methods are applied to the guidance design. The simulation results illustrate the effectiveness of the proposed methods. [ABSTRACT FROM AUTHOR]

• The PEG/Fe 3 O 4 /GO-NH 2 nanoadsorbent removed Ca2+ and Mg2+ from oilfield wastewater by 61–70 %. • The nanoadsorbent had relatively high reuse rates of 69–80 % at the fifth recycling run. • The oil recovery significantly increased by 11.8 % when the treated oilfield wastewater was reinjected. The high salinity of oilfield-produced water caused by the presence of metal ions, such as Ca2+ and Mg2+, has a significantly adverse effect on oil recovery. It is crucial to remove these metal ions efficiently before the oilfield wastewater is reinjected down into the oil wells. To address this issue, we prepared a PEG/Fe 3 O 4 /GO-NH 2 nanoadsorbent by aminating GO, incorporating magnetic Fe 3 O 4 nanoparticles and coating with PEG (PEG = poly(ethylene glycol); GO-NH 2 = aminated graphene oxide). We investigated the removal ratios of the nanoadsorbent for Ca2+ and Mg2+. The respective removal ratios for Ca2+ and Mg2+ reached 69.8 % and 61.1 % at 10 min, indicating that the nanoadsorbent was capable of efficiently removing Ca2+ and Mg2+. We also evaluated the reusability of the nanoadsorbent by recycling and reusing it 5 times. At the fifth recycling run, the nanoadsorbent retained relatively high reuse rates (79.1 % for Ca2+, 69.5 % for Mg2+) and removal ratios (69.5 % for Ca2+, 64.3 % for Mg2+), suggesting that the nanoadsorbent possessed relatively high reusability. Oilfield wastewater treated with the nanoadsorbent was employed for oil recovery in core displacement experiments. The oil recovery efficiency significantly increased by 11.8 % compared with untreated oilfield wastewater. Therefore, the PEG/Fe 3 O 4 /GO-NH 2 nanoadsorbent exhibits considerable potential for the treatment of oilfield wastewater to enhance oil recovery. [ABSTRACT FROM AUTHOR]