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Purpose: Gastric cancer (GC) remains a prevalent aggressive tumor with high morbidity and mortality globally. The identification of GC subtypes based on molecular features improved the prediction of prognosis and the selection of targeted therapies. PTEN is a characteristic tumor suppressor, while its association with different GC subtypes was unknown. Patients and Methods: The cohort consisted of 248 patients diagnosed with gastric cancer who were hospitalized and received radical gastrectomy. In addition, PTEN gene expression matrix of STAD was retrieved from TCGA. The mRNA and protein levels of PTEN and PD-L1 were detected using qRT-PCR and IHC staining. Multivariate logistic regression and Kaplan–Meier analysis were used to examine the relationship between PTEN expression and clinical characteristics. Results: In our study, PTEN was downregulated in gastric tumors both in mRNA and protein levels. Its inactivation was closely linked to higher histological grade (P = 0.005), neural invasion (P = 0.012), depth of invasion (P = 0.021), lymph metastasis (P = 0.026), and TNM stage (P = 0.001) of GC in the present study. Moreover, according to the molecular subtypes, high PTEN expression was related to high TPS score of PD-L1 positively (P = 0.010) but was not associated with MSI and EBV infection. Further, TCGA data validated that PTEN was indeed correlated with histological grade and invasion depth and positively related to PD-L1 expression (R = 0.29, adjusted P < 0.001). Conclusion: The above results suggested that PTEN expression was a useful marker in gastric carcinogenesis and progression and in the selection of immunotherapy-based treatments for GC patients. [ABSTRACT FROM AUTHOR]

This article proposes a mesh-based magneto-electric coupling network model for prediction and reduction of permanent magnet (PM) eddy current loss in a flux-switching permanent magnet machine. The key is to couple the electromagnetic inductions between the eddy current network and the equivalent magnetic network (EMN) in stator PMs dynamically. First, the eddy current networks of PMs are established with electric meshes. The electromotive forces of electric mesh are induced by considering double-side effects based on Maxwell's equations. Second, the stator meshing method is propose with PM segments, and combined in the EMN matching to the eddy current mesh. High efficiency and accuracy with detailed magnetic field distributions can be obtained. Then, the magnetic fields generated from EMN PM nodes are coupled in eddy current network to accurately predict the flow directions and density distributions. Finally, the original design and two other structures with rotor magnetic barriers are analyzed for reduction of eddy current losses. The effectiveness of the proposed model is verified by finite-element analyses and experimental results. [ABSTRACT FROM AUTHOR]

This article proposes a novel parametric equivalent magnetic network (EMN) modeling approach for multiobjective optimization of a surface-mounted permanent magnet (SPM) machine. The key is to apply variable meshes under adjustable topology to establish parametric EMN model. First, a novel adjustable cross-shape mesh method with variable sizes and regular permeance is proposed, which can flexibly vary with parameters. The meshes are combined in EMN model to simultaneously achieve high accuracy, high computing efficiency, and structural parameterization. Second, comprehensive sensitivity analyses are utilized to separate variable EMN parameters with the parametric feature. Significant variables are employed in multiobjective differential evolution algorithm with response surface models. Then, the optimal parameters are balanced and determined from Pareto front with improved torque performance. Finally, a prototype is manufactured, and the effectiveness of the proposed EMN-based optimization design method is verified by finite-element analysis and experimental results. [ABSTRACT FROM AUTHOR]

Background: 5-Hydroxymethylcytosine-enriched gene profiles and regions show tissue-specific and tumor specific. There is a potential value to explore cell-free DNA 5-hydroxymethylcytosine feature biomarkers for early gastric cancer detection. Methods: A matched case‒control study design with 50 gastric cancer patients and 50 controls was performed to sequence the different 5-hydroxymethylcytosine modification features of cell free DNA. Significantly differential 5-hydroxymethylcytosine modification genes were identified to construct a gastric cancer diagnostic model. Data set from GEO was used as an external testing set to test the robustness of the diagnostic model. Results: Accounting for more than 90% of 5-hydroxymethylcytosine peaks were distributed in the gene body in both the gastric cancer and control groups. The diagnostic model was developed based on five different 5-hydroxymethylcytosine modification genes, FBXL7, PDE3A, TPO, SNTG2 and STXBP5. The model could effectively distinguish gastric cancer patients from controls in the training (AUC = 0.95, sensitivity = 88.6%, specificity = 94.3%), validation (AUC = 0.87, sensitivity = 73.3%, specificity = 93.3%) and testing (AUC = 0.90, sensitivity = 81.9%, specificity = 90.2%) sets. The risk scores of the controls from the model were significantly lower than those of gastric cancer patients in both our own data (P < 0.001) and GEO external testing data (P < 0.001), and no significant difference between different TNM stage patients (P = 0.09 and 0.66). Furthermore, there was no significant difference between the healthy control and benign gastric disease patients in the testing set from GEO (P = 0.10). Conclusions: The characteristics of 5-hydroxymethylcytosine in cell free DNA are specific to gastric cancer patients, and the diagnostic model constructed by five genes' 5-hydroxymethylcytosine features could effectively identify gastric cancer patients. [ABSTRACT FROM AUTHOR]

AbstractThe cement-treated dredged mud mixture is suitable for backfill in earthwork projects because of its high water content and flowability. Incorporating geogrid can enhance the mixture’s tensile strength. Constructing with cement-treated mud at greater heights generates curing stress, affecting the interface with geogrid. Pullout tests were performed to analyze the impact of curing stress, water content, and cement content on the interface performance. Results showed similar pullout force-displacement curves regardless of curing stress, indicating strain-softening behavior. Higher water content resulted in decreased pullout forces, while higher cement content led to increased pullout forces. Samples under curing stress exhibited increased peak pullout forces ranging from 2% to 70% compared to samples without curing stress. The rate of increase in pullout force because of curing stress decreased with higher water or cement contents. Curing stress influenced the interface friction angle in specimens with water contents 1.5 and 2 times the liquid limit. It significantly affected the interface cohesion in samples with water contents 2.5 times the liquid limit. Samples subjected to curing stress demonstrated a higher apparent friction coefficient, with an average increase ranging from 4% to 43%, which decreased with higher water content and lower cement content, regardless of curing stress. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine whether the age‐Male‐ALBI‐Platelet (aMAP) score is applicable in community settings and how to maximise its role in risk stratification. A total of thousand five hundred and three participants had an aMAP score calculated at baseline and were followed up for about 10 years to obtain information on liver cancer incidence and death. After assessing the ability of aMAP to predict liver cancer incidence and death in terms of differentiation and calibration, the optimal risk stratification threshold of the aMAP score was explored, based on absolute and relative risks. The aMAP score achieved higher area under curves (AUCs) (almost all above 0.8) within 10 years and exhibited a better calibration within 5 years. Regarding absolute risk, the risk of incidence of and death from liver cancer showed a rapid increase after an aMAP score of 55. The cumulative incidence (5‐year: 8.3% vs. 1.3% and 10‐year: 20.9% vs. 3.6%) and mortality (5‐year: 6.7% vs. 1.1% and 10‐year: 17.5% vs. 3.1%) of liver cancer in individuals with an aMAP score of ≥55 were significantly higher than in those with a score of <55 (Grey's test p <.001). In terms of relative risk, the risk of death from liver cancer surpassed that from other causes after an aMAP score of ≥55 [HR = 1.38(1.02–1.87)]. Notably, the two types of death risk had opposite trends between the subpopulation with an aMAP score of ≥55 and < 55. To conclude, this study showed the value of the aMAP score in community settings and recommends using 55 as a new risk stratification threshold to guide subsequent liver cancer screening. [ABSTRACT FROM AUTHOR]

In this article, we propose an unconventional method, i.e., generalized finite difference method (GFDM), to analyze the electromagnetic performance of surface-mounted permanent magnet (SPM) machine with eccentric rotor shape. The remarkable characteristic of this method is that it is meshless. In this method, the solution region is discretized in the form of nodes, and the nodes can move with the moving structure. This is very helpful in modeling the SPM machine because there is no remeshing process during the rotation. However, mesh generation is required in the traditional finite-element analysis (FEA). First, the basic principle of the proposed GFDM is introduced. Second, the whole field domain is divided into five types of regions, viz., PMs, air gap, slot openings, slots, and stator core. Third, the differential equations satisfied by each region are discretized into algebraic equations by the GFDM. The interfaces need to be dealt with separately because of the discontinuity of the derivative of the vector potential. Then, the systems of equations are solved to analyze the electromagnetic performance of an SPM machine. Finally, this method is implemented on a 12-slot, 10-pole SPM machine. Meanwhile, the effectiveness of this method is verified by an FEA and experiment. [ABSTRACT FROM AUTHOR]

Robotic excavators commonly are used in industrial and construction tasks to improve efficiency and shorten construction periods, but they have high energy consumption and vibration and shock problems, the greatest of which is impact phenomenon in contact with construction environment. A perfect construction task with low vibration and high precision can be achieved only by skilled operators, and requires very intense concentration. Due to the urgent labor shortage caused by the pandemic, tight schedules, and increasingly complex construction projects, it is important for construction management to have an intelligent control method that combines the force and position of excavators in the construction progress. This study developed an adaptive impedance control method to realize coordinated control of force and position. An adaptive impedance control was designed to adjust the impedance parameters indirectly. Three different simulations were conducted to compare the force tracking performance of the classic impedance control and the proposed adaptive impedance control, namely, environmental location changes, environmental stiffness changes, and dynamic force tracking. Blended contact surfaces were designed to validate the performance of the control algorithms. Results show that the proposed adaptive impedance control effectively improved the force tracking accuracy. This paper offers an original contribution to the intelligent control method of excavator construction, and will be of use to operators, especially in large ground, mine, earthquake, and other complex ground construction sites. In addition, the research also provides construction manager and other practitioners with an impedance control method in construction project management that can save labor cost, improve production efficiency, and accelerate the transformation to a digital and intelligent construction industry. [ABSTRACT FROM AUTHOR]

Background: Primary Sjögren's syndrome is characterized by lymphocytic infiltration and dysfunction of exocrine glands. The persistent presence of lymphocytes in these glands is an important cause of injury to glandular epithelial cells. MicroRNAs play an important role in primary Sjögren's syndrome and regulate mRNA expression. This study evaluated the expression of microRNA related to lymphocyte infiltration in primary Sjögren's syndrome patients so as to find novel diagnostic and therapeutic targets for primary Sjögren's syndrome. We also explored the microRNA-mRNA networks related to lymphocyte infiltration.Methods: mRNA-seq and microRNA-seq of peripheral blood mononuclear cells (PBMCs) were performed on samples from five primary Sjögren's syndrome patients and five matched healthy controls. Meanwhile, microRNA-mRNA network analysis was also conducted. RT-qPCR was used for validation of differentially expressed RNAs. Immunohistochemistry analysis was used to detect MMP2 expression in labial gland tissue. Hsa-miR-3202 mimics/inhibitor-transfected Jurkat cells were used to measure the effects of hsa-miR-3202 on the infiltration potential of T cells.Results: mRNA and microRNA sequencing revealed that 84 differentially expressed mRNAs and 49 differentially expressed microRNAs had a mutual regulatory relationship. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis indicated that differentially expressed MMP2 and its related microRNA, hsa-miR-3202, were enriched in the leukocyte transendothelial migration pathway. MMP2 was highly expressed in PBMC and labial gland tissue in primary Sjögren's syndrome patients. Hsa-miR-3202 was lower expressed in primary Sjögren's syndrome than healthy control. Furthermore, hsa-miR-3202 mimics transfection decreased MMP2 expression in Jurkat cells, and inhibited Jurkat cells invasion (p = 0.047).Conclusion: Large number of differentially expressed microRNAs and mRNAs were detected in primary Sjögren's syndrome, and these differentially expressed microRNAs and mRNAs had a mutual regulatory relationship and played an important role in primary Sjögren's syndrome. In the study, we found hsa-miR-3202 regulate MMP2 and inhibited the infiltration of T cells from peripheral blood into the gland, which played a protective role. [ABSTRACT FROM AUTHOR]

This article proposes a new hybrid analytical model combining subdomain model and equivalent magnetic network for permanent magnet vernier machines, which are easy to get saturated due to the air-gap field modulation effect. The key is representing saturation effect by iterating equivalent surface current as part of interface conditions in the proposed subdomain model. First, five subdomains are divided to calculate magnetic field distribution. The equivalent surface current is utilized as the boundary constraint between subdomains and iron core. Second, the equivalent magnetic network is established based on stator structure, and the fluxes flowing into flux modulation poles are equivalent as the magnetic flux sources. Node magnetic potentials can be achieved with the application of Kirchhoff's law of current. Then, the equivalent surface current is updated for convergence by node magnetic potential to accurately predict saturated performance. Finally, a prototype is manufactured, and the effectiveness of the proposed hybrid model is verified by the finite-element analysis (FEA) and experimental results. The hybrid model combines the subdomain model and the equivalent magnetic network model to complement each other and it is demonstrated to be more efficient than the FEA model while maintaining high accuracy. [ABSTRACT FROM AUTHOR]

This paper investigates the effects of eccentric magnet design on sideband electromagnetic force (SEMF) and hence high-frequency vibroacoustic performance of integral-slot surface-mounted permanent magnet (SPM) machines. Also, the tangential SEMF components are considered to investigate their contribution for high-frequency vibration and acoustic noise. Firstly, the mechanism of sideband current harmonics introduced by space vector pulse-width modulation technique of open-winding drive system is derived. Moreover, the critical components of sideband synthetic magnet field in air-gap are derived to obtain the radial and tangential SEMF density components, and the effects of concentric magnet design of that is discussed. Then, the vibration synthesis model and acoustic radiation model are used to predict the vibroacoustic performance of machines. The results shows the eccentric magnet design can reduce the high-frequency vibration and noise of integral-slot SPM machines. Finally, two integral-slot SPM machines with concentric and eccentric magnets are manufactured and tested to validate the theoretical investigations. [ABSTRACT FROM AUTHOR]

Single-objective optimal trajectory cannot adapt to the complex requirements of excavator construction. A comprehensive optimal trajectory planning method is proposed to optimize the working time, energy consumption, and operational impact of robotic excavators. Without fusing any performance indexes, a normalized multi-objective function and an improved particle swarm optimization algorithm are established to achieve a comprehensive optimization of multiple objectives, while considering joint angle, velocity, acceleration, and quadratic acceleration constraints. Typical deep pit excavation simulation and experimental results show that the multi-objective optimization method is feasible, can balance multi-objective constraints, and can avoid falling into extremely long working times or large impacts. This method offers a more efficient and effective solution for multi-objective trajectory planning and provides a method for planning excavation trajectories based on different operating scenarios and objectives. • Working time, energy consumption and operation impact are considered in trajectory planning. • A normalized multi-objective function is established to achieve a comprehensive optimization. • An improved particle swarm optimization algorithm is proposed to obtain the optimal solution. • Effectiveness of the trajectory planning method is validated by simulations and experiments. • The multi-objective optimization method can meet the actual construction requirements. [ABSTRACT FROM AUTHOR]

In order to improve the trajectory tracking accuracy and robustness of a typical heavy electro-hydraulic position system, a fuzzy adaptive sliding mode controller is proposed. A potential-like function is introduced to design a new sliding surface with non-linear integral term. An adaptive controller is designed to approximate the equivalent controller in sliding mode control. Stability of the controller is demonstrated by Lyapunov method, and the chattering phenomenon caused by the nonlinear switching term is reduced by using the fuzzy switching method, 25 fuzzy rules are given to adjust the sliding mode switching controller. Simulations with sinusoidal, ramp and step signals, and experiments with leveling operation at different speeds are carried out. The proposed controller can follow the reference trajectory quickly and smoothly, and has certain anti-interference ability. Compared with the traditional sliding mode controller, the proposed controller has small tracking error, fast response and good tracking performances. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is a neurological condition that progresses with age. Amyloid-β (Aβ) aggregation has been suggested to be a key pathogenic process in Alzheimer's disease. Ginseng polysaccharides (GP), the main biologically active components isolated from Panax ginseng C. A. Meyer (ginseng), may act as neuroprotective agents with potential benefits for AD patients. However, GP effects on Aβ pathology and AD symptoms are still unclear. Here, a 4.7-kDa GP termed GP4 was purified and subjected to basic physicochemical characterization. The biological effects of GP4 to prevent Aβ aggregation were then assessed with cross-species AD models, including Aftin-5-treated SH-SY5Y cells and cerebral organoids, and transgenic C. elegans overexpressing the full-length human Aβ 42 peptide. These analyses ultimately demonstrated that GP4 was capable of inhibiting Aβ accumulation both in vivo and vitro , and with early intervention of GP4 being sufficient to alleviate Aβ 42 -associated aging phenotypes and memory loss in C. elegans model of AD. Furthermore, neuroinflammation was significantly down-regulated in human cells and cerebral organoids. From a mechanistic perspective, the ability of GP4 to inhibit Aβ aggregation was found to be related to its ability to promote neuronal mitophagic activity. This finding offers a robust theoretical foundation for the further development of GP4 as a candidate drugs with the potential to treat AD. [Display omitted] • A 4.7-kDa ginseng polysaccharides termed GP4 was purified from Panax ginseng and subjected to basic physicochemical characterization using HPGPC, HPLC, FT-IR and NMR analyses. • GP4 was capable of inhibiting Aβ accumulation in cross-species AD models, including Aftin-5-treated SH-SY5Y cells and cerebral organoids, and transgenic C. elegans overexpressing the full-length human Aβ 42 peptide. • Early intervention of GP4 being sufficient to alleviate Aβ 42 -associated aging phenotypes and memory loss in vivo. • Neuroinflammation was significantly down-regulated in vitro models of AD. • GP4 repressed Aβ accumulation via promoting neuronal mitophagic activity. [ABSTRACT FROM AUTHOR]

[Display omitted] • The effects of different operating temperatures on the hydrogen production and electricity generation of devices were analyzed. • Propose an energy management strategy based on the operating characteristics of the devices. • The abandoned and deficit electricity of the coupled system is much lower than that of the uncoupled system. The world is rich in renewable energy, and wind power generation accounts for a large proportion of renewable energy generation. The coupling of hydrogen energy and wind power generation will effectively solve the problem of energy surplus. In this study, a simulation model of a wind-hydrogen coupled energy storage power generation system (WHPG) is established. The effects of different operating temperatures on the hydrogen production and electricity consumption of alkaline electrolyzer, and on the electricity generation and hydrogen consumption of the fuel cell are studied. The suitable operating temperatures of the electrolyzer and fuel cell are determined. The energy management strategy of the coupled system is proposed considering the operating characteristics of the electrolyzer, fuel cell and hydrogen storage tank. Finally the economics of hydrogen energy storage systems are analyzed. The study shows that: (1) At the various operating temperatures, the maximum difference the electrolyzer is at 40 °C and 100 °C electrolyzer reduces electricity consumption by 0.26% and increases hydrogen production by 3.7%. (2) At different operating temperatures, the maximum difference the electrolyzer is at 30 °C and 100 °C. Fuel cell increases electricity production by 30.2% and reduces hydrogen consumption by 14.4%. (3) When the users' demand for electricity is the same, the uncoupled system 1-hour surplus electricity is about 19.5 times the coupled system 1-hour surplus electricity, the uncoupled system 1-hour deficit electricity is about 1.54 times the coupled system 1-hour deficit electricity. (4) The hydrogen storage system has a net present value of 2347,681 ¥, a dynamic payback period of 15.3 a and an internal rate of return of 11%, the coupled system has a better economics. The WHPG improves wind power utilization and power supply stability. [ABSTRACT FROM AUTHOR]

Marine umbilical provides the remote control function for offshore oil and gas exploitation, which is usually integrated by different functional components that vary widely in their mechanical properties. Under the action of external load, unreasonable cross-sectional layouts may lead to large cross-sectional deformation and contact pressure between components thus affecting the service life of an umbilical. Therefore, how to design the cross-sectional layout is a very necessary research work in order to improve service life of the umbilical to withstand various loads during operation. At present, the research on the cross-sectional layout of an umbilical is not sufficient, and there is no standardized design method in the design specification. Considering the mechanical and geometrical properties as the quantitative design objectives, the mathematical optimization model of the cross-sectional layout of an umbilical is proposed. Meanwhile, the layering strategy is introduced because of the processing and manufacturing factors. Then, the genetic algorithm (GA) with good global search performance and the generalized Lagrange multiplier (GLM) with fast convergence speed are combined to solve the above model. Finally, taking an umbilical as an example, the optimal cross-sectional layout is obtained and the effectiveness of the algorithm is verified by the numerical simulation. The results show that the optimization method proposed in this paper can quickly obtain the optimal design cross-sectional layout, and supply a specific way for the fast design of an umbilical, which has the certain engineering application value. • The cross-sectional layout design of the umbilical is a typical multi-objective optimization problem. • The quantifiable multi-objective optimization model for the cross-sectional layout of the umbilical is proposed. • The GA-GLM optimization algorithm with good global search ability and fast convergence speed is introduced. • The effectiveness of the optimization algorithm GA-GLM is verified by the numerical simulation. • The proposed multi-objective optimization algorithm can improve the design efficiency and avoid the manual process. [ABSTRACT FROM AUTHOR]

In the earthmoving automation procedure, the properties of large inertia, strong nonlinearity and flow coupling of multiple actuators are not considered comprehensively in relevant studies, which restricts the accuracy and efficiency performance of leveling tasks. To solve the problem of limited accuracy caused by the difficulty in modeling hydraulic flow coupling and the hysteresis of terminal compensation, we proposed a coordinated motion control method for an automatic earth excavation robot, which reduced the contour error from the perspective of force preloading and terminal control compensation. Various experiments show that the motion coordination of the proposed controller is significantly better than the PID-based controller and the contour-based controller. Due to its stability in multiple conditions, we believe the system will provide an effective earthmoving automation solution for different types of excavators in control. For further study, the soil force estimation will be integrated to improve the system performance under more tasks. • A multi-system mathematical model is established to describe the robotic excavator. • Contour and orientation control are integrated to make the cutting angle trajectory controllable. • Force pre-load and cross-coupling compensation algorithms are designed to improve control performance. • Effectiveness of the controller is verified for different angles and loads in leveling tasks. • The controller has better responsiveness and accuracy than PID-based and contour-based controllers. [ABSTRACT FROM AUTHOR]

C. albicans is the most prevalent opportunistic fungal and can cause life-threatening systemic infections under certain circumstances. The inefficiency and resistance of traditional therapy make the development of novel techniques indispensable. The main components, proteins and glycoproteins, of the C. albicans cell wall are highly immunogenic and very different from those of the host, making it an ideal source of targets for antifungal drug development. This study aimed to screen and identify specific peptides that bind to the C. albicans cell wall using a phage-display peptide library, and to develop a peptide-based therapy targeted to C. albicans. After four rounds of screening, JC-1 ScFv was found to bind to the C. albicans cell wall specifically, inhibit C. albicans growth and viability in vitro , and protect mice from C. albicans infection in vivo. Further study showed that JC-1 could provoke an immune response in C. albicans -infected mice. These results indicated that JC-1 ScFv screened from a phage-display peptide library had the potential to be developed as a vector for targeting C. albicans. • After four rounds of screening, JC-1 ScFv was able to bind to C. albicans cell wall specifically • JC-1 mAb protect mice from C. albicans infection in vivo. • JC-1 provoked an immune response in C. albicans -infected mice. • JC-1 had the potential to be developed as a vector for targeting C. albicans. [ABSTRACT FROM AUTHOR]

Background: Previous researches have associated Helicobacter pylori (H. pylori) with a prognosis of gastric cancer (GC), however, without a concert conclusion. This study aimed to study this issue further by a prospective cohort study and a meta-analysis.Methods: Histologically diagnosed gastric cancer (GC) patients were recruited into the primary prospective cohort study between January 2009 to December 2013. All the patients were followed-up periodically to record information on post-surgery therapy and overall survival status. The pre-surgery status of H. pylori was measured by enzyme-linked immunosorbent assay. A meta-analysis was conducted after retrieving related researches in the databases of PubMed and Embase up to April 2020. Pooled hazard ratios (HRs) and 95% confidence intervals (CIs) were summarized to validate the relationship between H. pylori infection and the survival time of GC patients. I2 statistics and Q test were used to assess the heterogeneity. Sensitivity analyses were performed using Galbraith's plot, leave-one-out analysis, subgroup analyses and meta-regression to explore the sources of heterogeneity and the stability of the summary results.Results: A total of 743 GC patients with radical tumorectomy were included prospectively and 516 (69.4%) were positive on H. pylori. H. pylori-positive patients tended to survive longer than -negative ones (HR 0.92, 95%CI: 0.74-1.15), though the tendency was not statistically significant. Cohort studies on the prognosis of GC were retrieved comprehensively by assessing the full-text and 59 published studies, together with the result of our study, were included in the further meta-analysis. The summarized results related the positive status of H. pylori to better overall survival (HR 0.81, 95%CI: 0.72-0.90) and disease-free survival (HR 0.83, 95%CI: 0.67-0.99). Results from subgroup analyses indicated that the pooled magnitude of this association was relatively lower in studies not referring to H. pylori in title and abstract.Conclusions: In conclusion, gastric cancer patients with H. pylori have a better prognosis than patients of H. pylori negative. More stringent surveillance strategies may be necessary for patients with H. pylori negative at cancer diagnosis. [ABSTRACT FROM AUTHOR]

This paper presents an improved particle swarm optimization (PSO) algorithm to optimize the coefficients of the proportional integral derivative (PID) controller for trajectory tracking accuracy problems. Nonlinear adaptive methods are adopted on the inertia weight to built a balance between the local and global search areas, asynchronous change strategies are introduced into the learning coefficients to rationally use individual and group experience, an elite mutation method is designed to mutate the global best position in each iteration. Basic PSO (BPSO-PID) and Ziegler-Nichols PID controller (ZN-PID) are implemented with step, sinusoidal and slope references on a co-simulation platform. The simulation results illustrate that high accuracy and fast convergence can be obtained based on the improved PSO algorithm PID controller (IPSO-PID). Experimental results demonstrated that the IPSO-PID method can achieve the highest tracking accuracy, compared with the BPSO-PID method, this method can improve the tracking accuracy by 37.14% and 50.32%, respectively. • An improved PSO algorithm based PID is proposed for improving trajectory tracking accuracy. • Three aspects are presented to avoid the shortcomings of the basic PSO algorithm. • Effectiveness of the improved PSO algorithm is validated by simulations and experiments. • High accuracy and fast convergence can be obtained based on the improved PSO algorithm. • The highest tracking accuracy can be obtained based on the improved PSO algorithm. [ABSTRACT FROM AUTHOR]