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AbstractThis article has investigated the friction behavior of a tribological system composed of a liquid crystal and polyimide. In this tribological system, ZrO2 and PMDA-ODA polyimide film used as a friction pair, and the liquid crystals used as lubricants including the single liquid crystal 5CB and the mixed liquid crystals LCs1 (5CB-5CEPO2), LCs2 (5CB-3CEPC3), LCs3 (5CB-2CEPPN), and conducted friction coefficient comparison experiments with n-hexadecane. It was found that the average friction coefficient of the LCs3 (90% 5CB + 10% 2CEPPN) is the smallest at the load of 5 N and the velocity of 200 rpm, which is 0.00113. Load and velocity selection experiments were investigated of LCs3, as well as polyimide film’s surface analysis including scanning electron microscope, white-light interference, polarization microscope, and surface-enhanced Raman scattering spectra. The results of the surface analysis indicated that some groups in the main chain and branch chain of the polyimide molecules are oriented parallel to the polyimide surface after rubbing. [ABSTRACT FROM AUTHOR]

Inhibition of the extracellular signal-regulated kinases 1/2 (ERK1/2) alone or in combination with other targets has emerged as a promising treatment strategy for a variety of human tumors. In addition to the development of inhibitors, the development of ERK1/2 degraders is an alternative approach to decrease its activity. We synthesized proteolysis-targeting chimeras (PROTACs) as effective ERK1/2 degraders, among which B1-10J showed high degradative activity, with DC50 of 102 nM and cytotoxic IC50 of 2.2 μM against HCT116 cells. Moreover, B1-10J dose-dependently inhibited tumor cell migration. Xenograft experiments in nude mice demonstrated that B1-10J inhibited HCT116 tumor cell growth and achieved significant regression of tumors at a daily dose of 25 mg/kg. [ABSTRACT FROM AUTHOR]

High-yield shale gas flow has been discovered in the Cambrian Shuijingtuo group shale (the Shuijingtuo shale) of the first shale gas well of Yichang, West Hubei, China. However, there are very few papers or reports involving high-performance water-based drilling fluid for the Shuijingtuo shale. X-ray diffraction (XRD) analysis and scanning electron microscope (SEM) tests were conducted on the outcrop of the Shuijingtuo shale samples collected from Zigui County, West Hubei. Then, the screening experiments on mud-making materials, salt additives, nanoparticles, fluid loss additives, mixed metal hydroxides (MMH), and surfactants were carried out. A high-performance water-based drilling fluid for the Shuijingtuo shale (the SWDF drilling fluid) was proposed based on physical plugging by nanoparticles, electrical property inhibition, and wettability control theory. Finally, comprehensive appraisals on rheology, filtration, lubricity, temperature resistance, inhibition, anti-pollution capability, and expense of the SWDF drilling fluid were accomplished. XRD results showed that the Shuijingtuo shale samples had 55%~67% brittle minerals. Clay minerals were mainly illite (13%~27%), and no montmorillonite was observed, which indicated that the Shuijingtuo shale was a weak-expansive rock. SEM analysis results show that pore and micro-cracks on the surface of the Shuijingtuo shale could provide natural channels for the invasion of drilling fluid. Nanomaterials were found to reduce the fluid loss of drilling fluid and thermal stability of the nano-silica dispersion was better. As a whole, the SWDF drilling fluid had suitable viscosity and gel strength, a low API fluid loss of 7.2 mL, a lubricity coefficient of 0.21, temperature-resistance capability up to 120°C, and good inhibition to shale hydration. In addition, it had excellent resistance capability to inorganic salts (NaCl, MgCl2, and CaCl2) and low-yield mud-making materials (simulated cuttings). Also, the cost of the SWDF drilling fluid was competitive compared to common oil-based drilling fluids. As a consequence, the SWDF drilling fluid can meet the requirements of drilling horizontal wells in the Shuijingtuo shale of West Hubei, China. [ABSTRACT FROM AUTHOR]

The set-union knapsack problem (SUKP) is a variation of the 0–1 knapsack problem (KP) in which each item is a set of elements, each item has a nonnegative value, and each element has a nonnegative weight. The weight of one item is given by the total weight of the elements in the union of the items' sets. The SUKP accommodates a number of real-life applications and is more complicated and computationally difficult than the 0–1 KP. In this paper, we propose a novel hybrid Jaya algorithm with double coding (DHJaya) to solve the SUKP. In the DHJaya, double coding is used to represent the individual, which includes the solutions for solving the SUKP by adopting a mapping function. The Jaya algorithm and differential evolution algorithm are combined to improve the exploration ability. To enhance the exploitation ability, the Cauchy mutation is performed on some individuals. Meanwhile, an improved repairing and optimization algorithm (MS-GROA) is proposed to repair the infeasible solutions and optimize the feasible solutions. We test the DHJaya using three sets of SUKP instances to demonstrate its efficiency, and the obtained results are compared with those in the previous study. Extensive experiments show a remarkable performance of the proposed approach. [ABSTRACT FROM AUTHOR]

Magnetorheological (MR) damper is one of the key technologies in the field of semi-active suspensions. However, the dynamic model and control strategy are not yet well established. A unified MR damper model and its inverse characterization are proposed to investigate MR damper dynamics. First, a novel unified model is proposed to describe the shear term of the MR damper force. This forward unified MR damper model uses one set of parameters to describe all MR force behavior under all currents and velocities, which agrees well with experimental data. Then, an inverse MR model based on the adaptive neuro-fuzzy inference system (ANFIS) technique has been established, where the precise training data are obtained from the proposed unified hysteretic model. A clear step-wise modeling process is proposed to decrease coupling degree of system which can be beneficial to improve inverse modeling efficiency. The inverse MR model is used for a semi-active suspension control, which can obtain the excitation current, exactly tracking the desired damping force computed by suspension control algorithm. Finally, validation of the proposed ANFIS inverse model has been conducted by comparison with three traditional empirical inverse approaches. The results reveal that the ANFIS inverse model could achieve much more tracking capability for the desired damping force and thus contributes to the development of semi-active suspension controllers. [ABSTRACT FROM AUTHOR]

In order to solve the uncapacitated facility location problem (UFLP) quickly and effectively, an enhanced group theory-based optimization algorithm (EGTOA) is proposed in this paper. Firstly, a new local search operator, One Direction Mutation Operator, is proposed, which is suitable for solving UFLP. Secondly, a Redundant Checking Strategy is presented to further optimize the quality of feasible solutions. To verify the performance of EGTOA, 15 benchmark instances of UFLP is selected in OR-Library, the comparison results with the 16 existing algorithms show that the solution obtained by EGTOA is better than other algorithms, moreover its speed is much faster than state-of-the-art algorithms. These demonstrates that EGTOA is a fast and effective algorithm for solving UFLP. • The one direction mutation operator is proposed for UFLP. • A redundant checking strategy is proposed to optimize UFLP's solution. • An enhanced group-theory optimization algorithm is proposed for solving UFLP. • Experiment confirms the superiority of the new algorithm for UFLP. [ABSTRACT FROM AUTHOR]

A group test gives a positive (negative) outcome if it contains at least u (at most l) positive items, and an arbitrary outcome if the number of positive items is between thresholds l and u. This problem introduced by Damaschke is called threshold group testing. It is a generalization of classical group testing. Chen and Fu extended this problem to the error-tolerant version and first proposed efficient nonadaptive algorithms. In this article, we extend threshold group testing to the k-inhibitors model in which a test has a positive outcome if it contains at least u positives and at most k−1 inhibitors. By using ( d + k − l, u; 2 e + 1]-disjunct matrix we provide nonadaptive algorithms for the threshold group testing model with k-inhibitors and at most e-erroneous outcomes. The decoding complexity is O( nu+ k log n) for fixed parameters ( d, u, l, k, e). [ABSTRACT FROM AUTHOR]

• A general algorithm framework for hardware software partitioning problem is proposed based on evolutionary algorithms. • An effective method to deal with the infeasible solution of hardware software partitioning problem is proposed • The performances of genetic algorithm (GA), binary particle swarm optimization (BPSO), binary differential evolution algorithm with hybrid encoding (HBDE), and group theory based optimization algorithm (GTOA) for solving hardware software partiti on ing problem are compared. • According to the comparison results, it is pointed out that GTOA and BPSO are more suitable for solving hardware software partitioning problem than GA and HBDE Hardware/software partitioning (HW/SW) is a significant problem in hardware-software co-design, and it is also an NP-hard problem. In order to solve the HW/SW quickly and effectively by evolutionary algorithms, the HW/SW is firstly regarded as a variant of knapsack problem. Based on a new greedy strategy, a greedy repair and optimization algorithm GROM is proposed to eliminate the infeasible solutions. Subsequently, a general algorithm framework based on discrete evolutionary algorithm for HW/SW problem is proposed. On the basis of the above algorithm framework, genetic algorithm (GA), binary particle swarm optimization (BPSO), binary differential evolution algorithm with hybrid encoding (HBDE) and group theory-based optimization algorithm (GTOA) are used to solve large-scale HW/SW instances. The feasibility and effectiveness of the algorithm framework proposed in the paper are verified by comparing the good and bad of the calculation results of above algorithms, and pointed out that the performance of GTOA and BPSO is better than that of HBDE and GA, they are more suitable for solving large-scale HW/SW problem. [ABSTRACT FROM AUTHOR]

This paper proposes a group theory-based optimization algorithm (GTOA) for knapsack problems, which draws algebraic group operations into the evolution process. The key parts of GTOA are that the feasible solution of the knapsack problem is considered as an element of the direct product of groups and that the evolution process is implemented by multiplication and inverse operations of the direct product of groups. Based on the algorithms for handling infeasible solutions, GTOA is used to solve knapsack problems such as the Set-union knapsack problem, the Discounted {0-1} knapsack problem, and the Bounded knapsack problem. GTOA is validated to be an efficient algorithm for solving knapsack problems. A comparison between GTOA and existing evolutionary algorithms such as genetic algorithm, binary particle swarm optimization, binary artificial bee colony, and their improved variations is conducted and the comparative results show that GTOA has a better performance than other algorithms. In addition, GTOA is not only an efficient algorithm for solving knapsack problems but is also the first paradigm that applies group theory to directly design an evolutionary algorithm. [ABSTRACT FROM AUTHOR]

Children's outdoor activities and their relationship with community space environments are of paramount importance for the development of child-friendly cities. This study investigates this connection within the context of Chengdu, China, utilizing quantitative research methods to provide both practical and theoretical insights. The research identifies key factors that influence children's outdoor experiences, including the flatness of paving surfaces, integration of natural elements, space richness, site scale, and specific features like watching spaces, play facilities, rest facilities, and accessibility to commercial amenities. A crucial finding of the study underscores the pivotal role of watching spaces in shaping children's outdoor activities, emphasizing the need for designs that balance parental supervision with children's independent play. Furthermore, the type and quantity of play facilities, along with the placement of rest facilities, emerged as significant determinants of children's outdoor engagement. The accessibility of commercial facilities also demonstrated a notable impact on children's outdoor activities. This research offers valuable quantitative insights for the development of child-friendly urban communities. Urban planners and community developers can use these findings to create environments that not only encourage but actively support children's outdoor activities, ultimately contributing to the creation of healthier, more vibrant communities for the future. [ABSTRACT FROM AUTHOR]

[Display omitted] • Thirty benzimidazole derivatives were designed and synthesized as novel potassium-competitive acid blockers (P-CABs). • A12 and A18 efficiently inhibited H+, K+-ATPase activity. • A12 and A18 significantly inhibited gastric acid secretion of SD rats in vivo. • A12 and A18 showed satisfactory drug stability and pharmacokinetic properties. H+, K+-ATPase, as the most critical enzyme in gastric acid secretion, has long been an attractive target for the treatment of acid-related diseases. In this study, a series of benzimidazole derivatives were designed and synthesized through conformational restriction and skeleton hopping strategies by using vonoprazan as the lead compound. Among them, compounds A12 (IC 50 = 9.32 μM) and A18 (IC 50 = 5.83 μM) showed better inhibition at the enzyme level. In addition, gastric acid secretion inhibition was assessed in vivo , and the results showed that A12 and A18 significantly inhibited basal gastric acid secretion, 2-deoxy- d -glucose (2DG) stimulated gastric acid secretion and histamine-stimulated gastric acid secretion. In further in vitro metabolic experiments, A12 and A18 demonstrated excellent stability and low toxicity. Pharmacokinetic studies showed that the p.o. and i.v. half-lives of A18 were 3.21 h and 8.67 ± 1.15 h, respectively. In summary, A18 might be a novel and effective potassium-competitive acid blocker, and this study provides strong support for it use in the treatment of acid-related diseases. [ABSTRACT FROM AUTHOR]

The combination of energy modeling and nanotechnology has been receiving increasing attention. Researchers have discovered that nanoparticles can plug shale pores. However, currently, information about the blocking effect of nanoparticles on shale pores is largely limited to physical experimental data. The migration, dynamic accumulation, and blocking mechanism of nanoparticles in a drilling fluid after intrusion into shale pores remain unclear. In this study, a CFD-DEM model was used to dynamically predict the quantitative relationship between nanoparticle parameters, fluid properties, and the shale pore plugging efficiency. To ensure rationality, UDF codes were written to correlate the standard drag curve. The results indicate that increasing the viscosity to 5 mPa·s is a highly effective method for improving the plugging efficiency at 1 wt% particle concentration. In addition, the effects of particle size, concentration, and fluid viscosity on the plugging effect are observed to be positively correlated. The plugging efficiency of a solution with 5 mPa·s viscosity was improved by 8.6%, 18.81%, and 18.77% compared with that of a solution with 1 mPa·s viscosity at particle sizes of 1/5, 1/3, and 1/2, respectively. Moreover, a pore roughness of 3% and a fluid viscosity of 5 mPa·s were determined to be the thresholds for improving the particle plugging efficiency. In addition, the simulation results were validated based on the results of a pressure transfer experiment. The findings of this study can serve as a reference for future research on nanoscale pore plugging with viscous flow. • CFD-DEM to model nanoparticle flows with viscosity is presented in shale pores. • UDF codes were written to correlate the drag curve for nanoscale plugging. • 5 mPa·s is an effective method for plugging increase of 16.26% at 1 wt% concentration. • 3% pore roughness and 5 mPa·s viscosity are threshold for particle plugging effect. • The simulation results are verified by theoretical formula and experiment results. [ABSTRACT FROM AUTHOR]