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AbstractIn this paper, we consider an almost cosymplectic 3-manifold M such that its scalar curvature is invariant along the Reeb vector field. We prove that if the Reeb vector field of M is harmonic, then M is conformally flat if and only if it is locally isometric to the product ℝ × N2(c), where N2(c) is a Kähler surface of constant sectional curvature c. Almost cosymplectic 3-manifolds on which the Reeb vector field satisfies the h-a condition together with conformal flatness are also classified. [ABSTRACT FROM AUTHOR]

Non-thermal atmospheric plasma (NTAP) has been proven to be an effective anti-tumor tool, with various biological effects such as inhibiting tumor proliferation, metastasis, and promoting tumor cell apoptosis. At present, the main conclusion is that ROS and RNS are the main effector components of NTAP, but the mechanisms of which still lack systematic summary. Therefore, in this review, we first summarized the mechanism by which NTAP directly or indirectly causes an increase in intracellular RONS concentration, and the multiple pathways dysregulation (i.e. NRF2, PI3K, MAPK, NF-κB) induced by intracellular RONS. Then, we generalized the relationship between NTAP induced pathways dysregulation and the various biological effects it brought. The summary of the anti-tumor mechanism of NTAP is helpful for its further research and clinical transformation. Non-thermal atmospheric plasma (NTAP) acts on NADPH oxidase and catalase. The feeding gas and parameters of NTAP affect its impacts on the signaling pathways. The impacts of NTAP and RONS on pathways are not always consistent. NTAP can trigger various anti-tumor biological effects. [ABSTRACT FROM AUTHOR]

As a swarm-based metaheuristic algorithm, the crow search algorithm (CSA) has attracted a lot of attention owing to its simplicity and flexibility. However, CSA tends to have low efficiency. To improve the optimization efficiency, this article proposes a modified version of CSA based on group strategy with an adaptive mechanism (GCSA). On this basis, crows are divided into multiple competing groups, and are assigned different roles and statuses. Then, the group strategy including different search modes is implemented to increase the solution diversity and search efficiency. Moreover, benefiting from the adaptive mechanism, the search range of crows changes in different stages to balance exploration and exploitation capabilities. To evaluate the performance of the proposed algorithm, 35 benchmark test functions (including 10 CEC2020 functions) and three engineering design problems are solved by GCSA and 11 other algorithms. The results prove that GCSA generally provides more competitive results than other metaheuristic algorithms. [ABSTRACT FROM AUTHOR]

Hantavirus infection is the main cause of hemorrhagic fever with renal syndrome (HFRS), which is common in Asia and Europe. There is a considerable risk of morbidity and mortality from the uncommon Hantavirus complication known as acute pancreatitis (AP). Retrospective analysis of the medical records of individuals with HFRS was performed. Relevant variables were assessed by univariate analyses and the variables with a p value <.05 were entered into the multivariable regression analysis. In this study, 114 individuals with HFRS in total were included, and 30 of them (26.32%) had AP. The univariate analyses showed that living in Xuancheng city (Anhui Province); an alcohol consumption history; white blood cell (WBC) count; lymphocyte (lym%) and eosinophil percentages (EO%); neutrophil (neut), eosinophil (EO), and red blood cell (RBC) counts; hemoglobin (Hb); hematocrit (HCT); proteinuria; hematuria; albumin (ALB), blood urea nitrogen (BUN), creatinine (Cr), uric acid (UA), cystatin-C (Cys-C) levels; carbon dioxide-combining power (CO2CP); fibrinogen degradation products (FDPs); and D-dimer level were significantly associated with HFRS complicated with AP (p <.05). In the multivariable regression analysis, an alcohol consumption history, lym%, proteinuria, FDPs and D-dimer level were found to be risk factors for HFRS complicated with AP (p <.05). Our findings indicate that HFRS patients with a history of consuming alcohol, a high lym%, intense proteinuria, high levels of FDPs, and a low level of D-dimer might be more prone to the development of AP. This is the first report employing Logistic regression analysis methods for exploring the risk factors for HFRS complicated with AP in China. Many factors (most are laboratory parameters) were significantly associated with HFRS complicated with AP. We found that HFRS patients with a history of consuming alcohol, a high lym%, intense proteinuria, high levels of FDPs, and a low level of D-dimer might be more prone to the development of AP. [ABSTRACT FROM AUTHOR]

This study aimed to explore the protective effects of L-theanine supplementation on the diquat-challenged weaned piglets. A total of 160 weaned piglets were randomly divided into 4 groups using a 2 × 2 two-factor design, there were 4 replicates per group and 10 pigs per replicate. Piglets were fed diets (with 1000 mg/kg L-theanine addition or not), then challenged with diquat or saline on day 7. 21 days after challenge, two pigs from each replicate were selected for sample collection. Results showed that supplement with 1000 mg/kg L-theanine down-regulated the diarrhea rate, serum D-lactate level, tumor necrosis factor-α, and phosphorylation of extracellular regulated protein kinases (ERK1/2), p38 mitogen-activated protein kinase (MAPK), and c-Jun N-terminal kinase (JNK) signaling in pigs without diquat challenge (p < 0.05). While for diquat-challenged piglets, L-theanine addition increased average daily gain, jejunum villus height, and interferon-γ level (p < 0.05). Meanwhile, L-theanine addition decreased the diarrhea rates and mortality, serum D-lactate level, and phosphorylation of ERK and JNK in diquat-challenged pigs (p < 0.05). These results demonstrate that L-theanine pretreatment could alleviate diquat-induced oxidative stress and improve intestinal barrier function in diquat-challenged weaned piglets, which can be attributed to suppression of MAPK phosphorylation signaling pathways. [ABSTRACT FROM AUTHOR]

Centrifugal pump optimization problems usually have strong nonlinear characteristics and are sometimes non-differentiable. The traditional multi-objective particle swarm optimization (MOPSO) algorithm was modified to solve this situation, and performed better with respect to both accuracy and search speed in validation experiments. Based on the modified algorithm and multi-layer artificial neural networks, the shape of the impeller blades of an industrial inline pump was optimized to improve the comprehensive performance under multiple operating conditions. The non-uniform rational B-spline was applied in the parametric design of the blade geometry, and 14 design variables of the spline were finally utilized in the iteration. With constraint of the computational head, the efficiencies of the part-load condition, the nominal condition, and the overload condition were selected as the objective functions. After optimization, a dramatic efficiency rise was obtained in all the three specified operating conditions, and correlation between the inflow conditions before the impeller and the performance of the inline pump was indicated. [ABSTRACT FROM AUTHOR]

In response to the need for explicitly linking field-based experiences with theoretical knowledge of pedagogy to effectively prepare teacher candidates, teacher educators are increasingly rethinking the opportunities they provide in their teacher education programs. In this action research article, we describe our efforts as teacher educators to connect pedagogical theories and strategies with practical experiences through a back-to-back integrated teaching approach. We explore how this experience provided early childhood teacher candidates with opportunities to engage with culturally appropriate practices in an authentic classroom setting. During this experience, teacher candidates were responsible for planning, teaching, and assessing children over a series of consecutive days. Using community of practice theory rooted in sociocultural perspectives, we provide a discussion of the themes that emerged as 13 early childhood teacher candidates navigated the organizational structures of this assignment. We focus on lessons we learned as well as teacher candidates' strengths that developed because of this assignment. The findings reveal the importance of providing teacher candidates with opportunities to learn how to build relationships with their students, preparing them to become culturally and linguistically responsive teachers, and providing opportunities for teacher candidates to learn about various assessments. Finally, we share the assignment protocol, reflection questions, and outcomes. [ABSTRACT FROM AUTHOR]

Sequential Approximate Optimization (SAO) has been widely used in engineering optimization design problems to improve efficiency. The infilling strategy is one of the critical techniques of the SAO, which is of paramount importance to the surrogate model accuracy and optimization efficiency. In this paper, an adaptive parallel infill strategy for surrogate-based single-objective optimization is proposed within a multi-objective optimization framework to balance exploration and exploitation during the optimization process. Within this method, an inaccurate Pareto Front is adopted to assist the infilling of the sampling points. The proposed SAO method with its adaptive parallel sampling strategy is tested on several numerical test cases and an engineering test case with the optimization results compared to state-of-the-art optimization algorithms. The results show that the proposed SAO with the adaptive parallel sampling strategy possesses excellent performance and better stability. [ABSTRACT FROM AUTHOR]

To broaden the efficient operating zone and increase the energy efficiency of a multi-stage double-suction centrifugal pump, a multi-component and multi-condition optimization design method involving high-precision performance predictions, a flow loss visualization technique based on entropy production theory, and machine learning is proposed. First, the accuracy of the baseline pump numerical methodology is verified via a grid convergence analysis and experiments. Thereafter, nine design parameters of the impeller and double volute are selected as design variables. Subsequently, 150 designs are created according to the Latin hypercube sampling method (LHS) and numerically simulated using an automatic simulation program. A backpropagation neural network (BPNN) and a multi-objective genetic algorithm (MOGA) are adopted to maximize the efficiency at 0.6Qd, 1.0Qd, and 1.2Qd. Finally, the optimal results are verified via numerical calculations and analyzed. The results indicate that the efficiency of the optimized pump is increased by 2.05%, 3.56%, and 5.36% at 0.6Qd, 1.0Qd, and 1.2Qd, respectively. The comparative analysis of the energy characteristics reveals that the improved performance of the optimized pump can be attributed to the improved matching between the rotor and stator. This research further demonstrates the accuracy and reliability of the optimization method using an artificial neural network (ANN). [ABSTRACT FROM AUTHOR]

Let M be a trans-Sasakian 3-manifold such that the Ricci curvature of the structure vector field vanishes. In this paper, it is proved that if M is compact, then it is homothetic to a cosymplectic manifold. Without the compactness assumption, we prove that M is locally isometric to the product of ℝ and a Kahler surface of constant curvature if the Ricci operator of M is of Codazzi type or cyclic parallel. We classify trans-Sasakian 3-manifolds with Killing type Ricci tensors. We construct some concrete examples to illustrate the above theorems. [ABSTRACT FROM AUTHOR]

Vascular smooth muscle cells (VSMCs) contribute to plaque stability. VSMCs are also a major source of CTH (cystathionine gamma-lyase)-hydrogen sulfide (H2S), a protective gasotransmitter in atherosclerosis. However, the role of VSMC endogenous CTH-H2S in pathogenesis of plaque stability and the mechanism are unknown. In human carotid plaques, CTH expression in ACTA2+ cells was dramatically downregulated in lesion areas in comparison to non-lesion areas. Intraplaque CTH expression was positively correlated with collagen content, whereas there was a negative correlation with CD68+ and necrotic core area, resulting in a rigorous correlation with vulnerability index (r = −0.9033). Deletion of Cth in VSMCs exacerbated plaque vulnerability, and were associated with VSMC autophagy decline, all of which were rescued by H2S donor. In ox-LDL treated VSMCs, cth deletion reduced collagen and heightened apoptosis association with autophagy reduction, and vice versa. For the mechanism, CTH-H2S mediated VSMC autophagosome formation, autolysosome formation and lysosome function, in part by activation of TFEB, a master regulator for autophagy. Interference with TFEB blocked CTH-H2S effects on VSMCs collagen and apoptosis. Next, we demonstrated that CTH-H2S sulfhydrated TFEB at Cys212 site, facilitating its nuclear translocation, and then promoting transcription of its target genes such as ATG9A, LAPTM5 or LDLRAP1. Conclusively, CTH-H2S increases VSMC autophagy by sulfhydration and activation of TFEB, promotes collagen secretion and inhibits apoptosis, thereby attenuating atherogenesis and plaque vulnerability. CTH-H2S may act as a warning biomarker for vulnerable plaque. Abbreviations ATG9A: autophagy related 9A; CTH: cystathionine gamma-lyase; CQ: chloroquine; HASMCs: human aortic smooth muscle cells; H2S: hydrogen sulfide; LAMP1: lysosomal associated membrane protein 1; LAPTM5: lysosomal protein transmembrane 5; NaHS: sodium hydrosulfide hydrate; ox-LDL: oxidized-low density lipoprotein; PPG: DL- propagylglycine; TFEB: transcription factor EB; 3-MA: 3-methyladenine; VSMCs: vascular smooth muscle cells. [ABSTRACT FROM AUTHOR]

In recent decades, surrogate-based optimization (SBO) has been developed to replace costly models with cheap surrogates to improve efficiency. In this article, an adaptive parallel infill strategy is proposed to balance exploration and exploitation over the design space during the optimization process of SBO. Within this method, an inaccurate search strategy is adopted to optimize the surrogate models, thereby helping to locate the exploitation point. An elite archive is exploited to store superior sampling points for batch sampling, while a customized batch size determination strategy is introduced. The proposed SBO method with its adaptive parallel sampling strategy is tested on six unconstrained and five constrained analytical cases with the optimization results compared to state-of-the-art optimization algorithms. The optimization of a 582-bar tower truss system is also performed and utilized to verify the proposed SBO method. The proposed SBO with the adaptive parallel sampling strategy shows excellent performance and better stability. [ABSTRACT FROM AUTHOR]

Cache is the bridge between CPU and memory for data exchange, which consumes up to 45% of the entire CPU energy. Low power cache and memory are urgently required for the computer system. The paper focuses on using Destiny to simulate the scaling roadmap of the STT-MRAM. The performance evaluation of the STT-MRAM is explored in the cache applications, including the cell area, the aspect ratio for different cache capacities. Based on the exploration, optimisation on the performance is achieved, showing a write latency reduction of up to 5.4% and a total leakage power reduction of up to 42.1%, suggesting an important application scenario for the STT-MRAM. Furthermore, comparison is conducted in the cache performance between SRAM and STT-MRAM using high performance (HP) and low power performance (LOP) device models, including the capacity, total area, hit latency, write latency, total leakage power, hit dynamic energy and write dynamic energy. It is interesting to disclose that the STT-MRAM memory bank with large-capacity (> 32 MB) shows better performances. The large cache with the STT-MRAM exhibits better performances than the cache based on the SRAM. Especially for the STT-MARM using LOP device model compared with the SRAM using LOP device model, it can effectively reduce energy consumption. [ABSTRACT FROM AUTHOR]

This article presents and validates a new branch-and-bound algorithm for effectively solving the generalized polynomial problem (GPP). In this algorithm, a new affine relaxed technique is derived for establishing the relaxed linear programs problem of the GPP. In addition, some box reducing manipulations are employed to improve the speed of branch-and-bound search of the algorithm. Combining the relaxed linear programs problem with the box reducing manipulations, a new branch-and-bound algorithm is constructed. Some numerical examples are solved to verify the potential practical and computing advantages of the algorithm. At last, several engineering design problems are solved to validate the usefulness of the algorithm. [ABSTRACT FROM AUTHOR]

Aircraft optimization design problems are mostly computationally intensive. These complicated problems probably contain mixed-variables, while most research has focused on continuous variables. This article sets up a mixed-variable surrogate-based optimization algorithm framework that includes a mixed-variable experiment design method and an inaccurate infilling method. The mixed-variable experiment design method combines improved successive local enumeration with enhanced stochastic evolution to deal directly with discrete variables. The inaccurate infilling method tends to find points with better fitness value and relatively low sample density so as to balance exploration and exploitation. Several numerical functions and a mixed-variable solid rocket motor performance matching design problem are solved using the modified surrogate-based optimization method. The results indicate that the proposed method is competitive compared with other heuristic algorithms and surrogate-based algorithms, and can deal with mixed-variable aircraft design problems effectively. [ABSTRACT FROM AUTHOR]

Gaseous and vaporous cavitation have extremely harmful effects on hydraulic axial plunger pumps, reducing flowrate and increasing flow pulsation. The collapse of vapor bubbles strongly impacts the inner wall and produces many pits. Therefore, it is very important to reduce gaseous and vaporous cavitation to improve the performance of hydraulic axial plunger pumps. In this work, a full cavitation model and a compressible model are used to simulate the two kinds of cavitation, which are validated by a series of experiments. It is found that the vapor and gaseous bubbles in the plunger chamber collapse owing to pressurization caused by the water hammer effect. The results show that a better combination of plunger chamber radius and swash plate angle can reduce the two kinds of cavitation when the theoretical flowrate is unchanged; increasing the angle of the inlet of valve plate can effectively reduce its cavitation and increase the filling mass of plunger chambers; increasing the angle of the relief groove can significantly reduce its vapor and gaseous volume fraction. The results can provide a useful reference for reducing gaseous and vaporous cavitation in the optimization and design of hydraulic axial plunger pumps. [ABSTRACT FROM AUTHOR]

Coal gangue is used to prepare flake nano-mullite with a molten salt method. In order to increase the utilization value, corundum composite ceramics were prepared from the nanomullite and alumina. The effect of particle size of the raw material size and the content of mullite on mechanical properties of the corundum composite ceramics was studied. It is found that the mullite with appropriate sizes can be filled in between the corundum grains, thus increasing the density of the samples. The mechanical properties were enhanced due to the variation in the crack propagation mode. The optimized sample exhibited flexural strength and fracture toughness of 263.7 MPa and 5.0 MPa·m1/2, respectively. Griffith fracture theory analysis results indicated that the critical crack size reached 173.9 μm and the fracture energy was 127.6 J/m2. Coal gangue has realized deep resource utilization, and the mechanical properties of composite ceramics are higher than alumina ceramics prepared under the same conditions. Flake nanomullite contributes to mechanical properties. [ABSTRACT FROM AUTHOR]

Background: Tuberculosis in patients with diabetes mellitus is characterised by rapid disease progression, poor treatment efficacy, poor prognosis and poses a new challenge in tuberculosis treatment and control. Methods: Patients with pulmonary TB and type 2 DM were recruited at Yijishan Hospital of Wannan Medical College. A total of 348 patients were randomly assigned to two groups. The aspirin group (aspirin + TB/DM) included 174 patients who received anti-TB therapy and enteric-coated aspirin tablets (100 mg/tablet). The control group (placebo + TB/DM) included 174 patients who received anti-TB therapy and enteric-coated placebo tablets (an identical tablet containing no drug). Eighty-two patients in the aspirin group and 86 in the control group completed the trial and were included in the analysis. Clinical characteristics, laboratory test results, imaging data and side effects of aspirin were monitored. Results: Aspirin treatment affect certain signs and symptoms. The erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels were lower in the aspirin group than in the control group after treatment (Both p =.000). The sputum-negative conversion rate was 86.7% in the aspirin group, significantly higher than in the control group (53.8%) (p =.031). After two months of treatment, the differences in the number of cases with cavities, the number of cavities, and maximum diameter of cavities in the aspirin group were statistically significant (p =.003, p =.023 and p =.015 respectively). Conclusion: Our findings suggest that aspirin may improve treatment in patients with pulmonary TB and type 2 DM. [ABSTRACT FROM AUTHOR]

Conventional space-filling experimental design provides uniform coverage of a hypercube design space. When constraints are imposed, the results may contain many infeasible points. Simply omitting these points leads to fewer feasible points than desired and a design of experiments that is not optimally distributed. In this research, an adaptive method is developed to create space-filling points in arbitrarily constrained spaces. First, a design space reconstruction method is developed to reduce the invalid exploration space and enhance the efficiency of experimental designs. Then, a synthetic criterion of uniformity and feasibility is proposed and optimized by the enhanced stochastic evolutionary method to obtain the initial sampling combination. Finally, an adaptive adjustment strategy of design levels is constructed to obtain the required number of feasible points. Various test cases with convex and non-convex, connected and non-connected design spaces are implemented to verify the efficacy of the proposed method. [ABSTRACT FROM AUTHOR]

A critical task in single-cell RNA sequencing (scRNA-Seq) data analysis is to identify cell types from heterogeneous tissues. While the majority of classification methods demonstrated high performance in scRNA-Seq annotation problems, a robust and accurate solution is desired to generate reliable outcomes for downstream analyses, for instance, marker genes identification, differentially expressed genes, and pathway analysis. It is hard to establish a universally good metric. Thus, a universally good classification method for all kinds of scenarios does not exist. In addition, reference and query data in cell classification are usually from different experimental batches, and failure to consider batch effects may result in misleading conclusions. To overcome this bottleneck, we propose a robust ensemble approach to classify cells and utilize a batch correction method between reference and query data. We simulated four scenarios that comprise simple to complex batch effect and account for varying cell-type proportions. We further tested our approach on both lung and pancreas data. We found improved prediction accuracy and robust performance across simulation scenarios and real data. The incorporation of batch effect correction between reference and query, and the ensemble approach improve cell-type prediction accuracy while maintaining robustness. We demonstrated these through simulated and real scRNA-Seq data. [ABSTRACT FROM AUTHOR]