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Variable stiffness design optimization of fiber-reinforced composite laminates with regular and irregular holes considering fiber continuity for additive manufacturing 被引量:1
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作者 Yi LIU Zunyi DUAN +6 位作者 Chunping ZHOU Yuan SI Chenxi GUAN Yi XIONG Bin XU Jun YAN Jihong ZHU 《Chinese Journal of Aeronautics》 2025年第3期334-354,共21页
Fiber-reinforced composites are an ideal material for the lightweight design of aerospace structures. Especially in recent years, with the rapid development of composite additive manufacturing technology, the design o... Fiber-reinforced composites are an ideal material for the lightweight design of aerospace structures. Especially in recent years, with the rapid development of composite additive manufacturing technology, the design optimization of variable stiffness of fiber-reinforced composite laminates has attracted widespread attention from scholars and industry. In these aerospace composite structures, numerous cutout panels and shells serve as access points for maintaining electrical, fuel, and hydraulic systems. The traditional fiber-reinforced composite laminate subtractive drilling manufacturing inevitably faces the problems of interlayer delamination, fiber fracture, and burr of the laminate. Continuous fiber additive manufacturing technology offers the potential for integrated design optimization and manufacturing with high structural performance. Considering the integration of design and manufacturability in continuous fiber additive manufacturing, the paper proposes linear and nonlinear filtering strategies based on the Normal Distribution Fiber Optimization (NDFO) material interpolation scheme to overcome the challenge of discrete fiber optimization results, which are difficult to apply directly to continuous fiber additive manufacturing. With minimizing structural compliance as the objective function, the proposed approach provides a strategy to achieve continuity of discrete fiber paths in the variable stiffness design optimization of composite laminates with regular and irregular holes. In the variable stiffness design optimization model, the number of candidate fiber laying angles in the NDFO material interpolation scheme is considered as design variable. The sensitivity information of structural compliance with respect to the number of candidate fiber laying angles is obtained using the analytical sensitivity analysis method. Based on the proposed variable stiffness design optimization method for complex perforated composite laminates, the numerical examples consider the variable stiffness design optimization of typical non-perforated and perforated composite laminates with circular, square, and irregular holes, and systematically discuss the number of candidate discrete fiber laying angles, discrete fiber continuous filtering strategies, and filter radius on structural compliance, continuity, and manufacturability. The optimized discrete fiber angles of variable stiffness laminates are converted into continuous fiber laying paths using a streamlined process for continuous fiber additive manufacturing. Meanwhile, the optimized non-perforated and perforated MBB beams after discrete fiber continuous treatment, are manufactured using continuous fiber co-extrusion additive manufacturing technology to verify the effectiveness of the variable stiffness fiber optimization framework proposed in this paper. 展开更多
关键词 Variable stiffness composite laminates Discrete material interpolation scheme Normal distribution fiber optimization Discrete fiber continuous filtering strategy Additive manufacturing of composite laminates
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On α-Bloch Functions in Several Complex Variables
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作者 ZHU Ting YANG Liu 《Chinese Quarterly Journal of Mathematics》 2025年第1期93-102,共10页
In this paper,we establish characterizations of α-Bloch functions and little α-Bloch functions on the unit ball as well as the unit polydisk of C^(m),which generalize and improve results of Aulaskari-Lappan,Minda,Au... In this paper,we establish characterizations of α-Bloch functions and little α-Bloch functions on the unit ball as well as the unit polydisk of C^(m),which generalize and improve results of Aulaskari-Lappan,Minda,Aulaskari-Wulan,and Wu.Some examples are also given to complement our theory. 展开更多
关键词 α-Bloch function Littleα-Bloch function several complex variables Partial derivative
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Evaluating the Impact of Different Electrocardiogram Methods on Detecting Pacemaker Dysfunction and Cardiac Function Changes in Pacemaker Patients
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作者 Yan Li Chun Zhou +1 位作者 Ying Li Binlin Chen 《Journal of Clinical and Nursing Research》 2025年第8期7-13,共7页
Objective:To investigate the effect of 12-lead electrocardiogram and 24-hour dynamic electrocardiogram in detecting pacemaker dysfunction and changes in cardiac function indexes in patients with pacemaker implantation... Objective:To investigate the effect of 12-lead electrocardiogram and 24-hour dynamic electrocardiogram in detecting pacemaker dysfunction and changes in cardiac function indexes in patients with pacemaker implantation.Methods:A total of 136 patients with pacemaker implantation in the First Clinical Medical College of Three Gorges University,Institute of Cardiovascular Disease of Three Gorges University and Yicang Central People’s Hospital from January 2023 to December 2024 were selected as the research objects.All patients received 12-lead electrocardiogram and 24-hour holter 3–14 days after implantation.Results:The overall detection rate of various types of pacemaker dysfunction by Holter was significantly higher than that by conventional ECG(27.21%vs.5.15%,χ^(2)=24.402,P<0.001).The overall arrhythmia detection rate of Holter was significantly higher than that of conventional electrocardiogram(57.35%vs.10.29%,χ^(2)=67.277,P<0.001).The time domain indexes of heart rate variability obtained by 24-hour continuous monitoring of Holter were significantly improved compared with those of conventional electrocardiogram(P<0.05).Conclusions:Compared with 12-lead electrocardiogram,24-hour holter monitoring can more accurately detect pacemaker dysfunction and arrhythmia in patients with pacemaker implantation,and provide more comprehensive data of heart rate variability,which is helpful for clinicians to better evaluate the cardiac function of patients and adjust treatment plans. 展开更多
关键词 Pacemaker implantation ELECTROCARDIOGRAM Abnormal pacemaker function Cardiac arrhythmia Heart rate variability
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Association of heart rate variability index with depressive symptoms and lung function in chronic obstructive pulmonary disease
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作者 Ya-Ping Yang Mei-Jia Ji +1 位作者 Yue-Han Guo Na Yao 《World Journal of Psychiatry》 2025年第5期127-135,共9页
BACKGROUND Depression is a common comorbidity in patients with chronic obstructive pulmonary disease(COPD).Research indicates that COPD affects cardiac au-tonomic control,and heart rate variability(HRV)serves as a sim... BACKGROUND Depression is a common comorbidity in patients with chronic obstructive pulmonary disease(COPD).Research indicates that COPD affects cardiac au-tonomic control,and heart rate variability(HRV)serves as a simple,non-invasive measure of autonomic nerve activity.However,the relationship between HRV and lung function,as well as the impact of depressive symptoms,remains un-clear.METHODS A retrospective cross-sectional study involving 120 COPD patients hospitalized from January 2018 to January 2024 at our institution was conducted.Demographic and clinical characteristics were collected,and depressive symptoms were asse-ssed using the Beck Depression Inventory(BDI).Patients were categorized into a depressed group(BDI≥16)and a non-depressed group(BDI<16).A control group consisting of 60 healthy volunteers who underwent check-ups at the same institution was also included.Statistical analyses were performed using SPSS 26.0 software.Pearson correlation coefficients were calculated to determine and compare the relationships between HRV parameters,lung function measures,and RESULTS Of the 120 patients with COPD,35.8%(43/120)were diagnosed with depression,compared to 5.0%(3/60)in the control group.The HRV index in COPD patients was significantly lower than that in the control group(P<0.05),and the value in the depressed group was significantly lower than that in the non-depressed group(P<0.05).Similarly,the COPD group had a significantly lower pulmonary forced vital capacity(FVC),first-second expiratory volume(FEV1)and FEV1/FVC ratios than the control group(P<0.05),and the depressed group was significantly lower than that in the non-depressed group(P<0.05).Pearson correlation analysis revealed that the standard deviation of normal R-R intervals,standard deviation of the mean of 5-minute normal R-R intervals,root mean square of successive differences of normal R-R intervals,percentage of normal R-R intervals greater than 50 ms,high-frequency,and low-frequency indices showed positive correlations with lung function parameters(P<0.05)and negative correlations with BDI scores(P<0.05).CONCLUSION Compared to patients without COPD,the incidence of depressive symptoms is higher among patients with COPD and is negatively correlated with the patients’HRV indices.In contrast,HRV indices are positively correlated with the patients’pulmonary function parameters.Patients and healthcare professionals should enhance their awareness of depression,actively conduct depression assessment screenings,and incorporate HRV indices into disease management.This approach aims to improve the psychological health of patients and ultimately enhance their prognosis and quality of life. 展开更多
关键词 Chronic obstructive pulmonary disease Heart rate variability Lung function DEPRESSION Beck depression inventory
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Continuity of truncated Hardy-Littlewood maximal function
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作者 WANG Yidong WU Jia YAN Dunyan 《中国科学院大学学报(中英文)》 CAS CSCD 北大核心 2024年第6期721-727,共7页
This paper focuses on the continuity of the truncated Hardy-Littlewood maximal function.We first show that the truncated Hardy-Littlewood maximal function is lower semi-continuous.Then by investigating the behavior of... This paper focuses on the continuity of the truncated Hardy-Littlewood maximal function.We first show that the truncated Hardy-Littlewood maximal function is lower semi-continuous.Then by investigating the behavior of the truncated Hardy-Littlewood maximal function when the truncated parameterγchanges,we obtain an equivalent condition of the continuity of the truncated Hardy-Littlewood maximal function. 展开更多
关键词 Hardy-Littlewood maximal function TRUNCATION continuity truncated parameter
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Wave propagation of a functionally graded plate via integral variables with a hyperbolic arcsine function
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作者 Mokhtar Ellali Mokhtar Bouazza Ashraf M.Zenkour 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第3期547-561,共15页
Several studies on functionally graded materials(FGMs)have been done by researchers,but few studies have dealt with the impact of the modification of the properties of materials with regard to the functional propagati... Several studies on functionally graded materials(FGMs)have been done by researchers,but few studies have dealt with the impact of the modification of the properties of materials with regard to the functional propagation of the waves in plates.This work aims to explore the effects of changing compositional characteristics and the volume fraction of the constituent of plate materials regarding the wave propagation response of thick plates of FGM.This model is based on a higher-order theory and a new displacement field with four unknowns that introduce indeterminate integral variables with a hyperbolic arcsine function.The FGM plate is assumed to consist of a mixture of metal and ceramic,and its properties change depending on the power functions of the thickness of the plate,such as linear,quadratic,cubic,and inverse quadratic.By utilizing Hamilton’s principle,general formulae of the wave propagation were obtained to establish wave modes and phase velocity curves of the wave propagation in a functionally graded plate,including the effects of changing compositional characteristics of materials. 展开更多
关键词 FGM plate effects of material properties wave propagation indeterminate integral variables inverse sinus hyperbolic function
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Clinical Study on the Effect of Continuity of Care in CICU on Improving Cognitive Function and Psychological State in Patients with Heart Failure
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作者 Jin Sang Yuqing Xie Xintong Zhu 《Journal of Clinical and Nursing Research》 2024年第10期133-139,共7页
Objective:To analyze the effect of continuity of care in the cardiac intensive care unit(CICU)on improving cognitive function and psychological state in patients with heart failure(HF).Methods:A total of 112 chronic H... Objective:To analyze the effect of continuity of care in the cardiac intensive care unit(CICU)on improving cognitive function and psychological state in patients with heart failure(HF).Methods:A total of 112 chronic HF patients admitted to the CICU of Xuzhou Traditional Chinese Medicine Hospital from July 2022 to August 2024 were selected and randomly divided into two groups using the red and blue ball method:a control group(n=56)and a study group(n=56).The control group received routine CICU nursing management,while the study group received routine CICU nursing combined with continuity of care management.Cognitive function(using the Montreal Cognitive Assessment,MoCA),psychological state(using the Self-Rating Depression Scale,SDS,and Self-Rating Anxiety Scale,SAS),and quality of life(using the Minnesota Living with Heart Failure Questionnaire,MLHFQ)were compared between the two groups.Results:After the intervention,the cognitive function scores of the study group were significantly higher than those of the control group(P<0.05).The SDS and SAS scores of the study group were significantly lower than those of the control group after the intervention(P<0.05).The quality of life in the study group was also significantly better than in the control group(P<0.05).Conclusion:CICU continuity of care can effectively improve cognitive function and psychological state in patients with HF,while also enhancing their quality of life. 展开更多
关键词 CICU continuity of care Heart failure patients Cognitive function Psychological state
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SOME RESULTS REGARDING PARTIAL DIFFERENTIAL POLYNOMIALS AND THE UNIQUENESS OF MEROMORPHIC FUNCTIONS IN SEVERAL VARIABLES
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作者 刘曼莉 高凌云 房少梅 《Acta Mathematica Scientia》 SCIE CSCD 2023年第2期821-838,共18页
In this paper,we mainly investigate the value distribution of meromorphic functions in Cmwith its partial differential and uniqueness problem on meromorphic functions in Cmand with its k-th total derivative sharing sm... In this paper,we mainly investigate the value distribution of meromorphic functions in Cmwith its partial differential and uniqueness problem on meromorphic functions in Cmand with its k-th total derivative sharing small functions.As an application of the value distribution result,we study the defect relation of a nonconstant solution to the partial differential equation.In particular,we give a connection between the Picard type theorem of Milliox-Hayman and the characterization of entire solutions of a partial differential equation. 展开更多
关键词 meromorphic function in several variables Nevanlinna theory partial differ-ential equation total derivative
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FRACTIONAL INTEGRALS OF PERIODIC FUNCTIONS OF SEVERAL VARIABLES
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作者 Wang Shiming 《Analysis in Theory and Applications》 1993年第1期82-96,共15页
In this paper it has been systematically studied the imbedding properties o f fractional integral operators of periodic functions of several variables,and isomorphic properties of fractional intregral operators in the... In this paper it has been systematically studied the imbedding properties o f fractional integral operators of periodic functions of several variables,and isomorphic properties of fractional intregral operators in the spaces of Lipschitz continuous functions. It has also been proved that the space of fractional integration,the space of Lipschitz continuous functions and the Sobolev space are identical in L^2-norm.Results obtainedhere are not true for fractional integrals(or Riesz potentials)in R^n. 展开更多
关键词 TH FRACTIONAL INTEGRALS of PERIODIC functionS of several variables
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Traction performance and efficiency of cone friction CVT
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作者 Vít Ripa Karel Petr +2 位作者 Jan Flek Gabriela Achtenová Frantisek Lopot 《Theoretical & Applied Mechanics Letters》 2025年第2期168-178,共11页
This study investigates the traction performance and efficiency of a conical friction continuously variable trans-mission.A new mathematical model was developed and validated through experimental measurements using a ... This study investigates the traction performance and efficiency of a conical friction continuously variable trans-mission.A new mathematical model was developed and validated through experimental measurements using a custom-built test rig to predict these parameters accurately.The results showed a close correlation between the-oretical predictions and experimental data.Key findings include the impact of load on efficiency and the model’s ability to predict performance under various operating conditions.The study provides detailed insights into the dynamics of conical friction variator and demonstrates the model’s effectiveness in predicting real-world behav-ior.The developed model can assist in selecting optimal parameters during the design phase and can be applied to other developing variator systems to achieve maximum efficiency. 展开更多
关键词 Continuously variable transmission Conical continuously variable transmissions Friction gear SPIN Creep EFFICIENCY
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Analysis of the Effectiveness of Continuous Nursing Interventions in Elderly Patients with COPD in the Stable Phase and Frailty
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作者 Chuo Guo Yaran Li +1 位作者 Jiao Chen Yuanyuan Lu 《Journal of Clinical and Nursing Research》 2025年第1期107-112,共6页
Objective:To evaluate the effectiveness of continuous nursing interventions in elderly patients with COPD in the stable phase and frailty.Methods:Sixty elderly patients with COPD in the stable phase and frailty,treate... Objective:To evaluate the effectiveness of continuous nursing interventions in elderly patients with COPD in the stable phase and frailty.Methods:Sixty elderly patients with COPD in the stable phase and frailty,treated between January 2024 and August 2024,were selected as the study subjects.Patients were randomly divided into two groups(30 each)using a drawing method.Patients who drew a black token were assigned to the intervention group and received continuous nursing interventions,while those who drew a red token were assigned to the nursing group and received standard nursing care.The quality of care between the groups was compared.Results:Pulmonary function indicators in the intervention group were significantly better than those in the nursing group(P<0.05).Immune function in the intervention group was also significantly higher than in the nursing group(P<0.05).Before the intervention,there was no significant difference in self-care ability between the two groups(P>0.05).However,post-intervention,both groups showed improved self-care abilities,with the intervention group scoring significantly higher than the nursing group(P<0.05).Similarly,before the intervention,there was no significant difference in quality-of-life scores(P>0.05),but post-intervention,both groups exhibited increased scores,with the intervention group outperforming the nursing group significantly(P<0.05).Conclusion:Continuous nursing interventions significantly improve outcomes in elderly patients with COPD in the stable phase and frailty,warranting broader implementation. 展开更多
关键词 Continuous nursing Stable COPD Elderly patients Pulmonary function Immune function
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Detection of Rice Bacterial Leaf Blight Using Hyperspectral Technology and Continuous Wavelet Analysis
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作者 Kaihao Shi Lin Yuan +5 位作者 Qimeng Yu Zhongting Shen Yingtan Yu Chenwei Nie Xingjian Zhou Jingcheng Zhang 《Phyton-International Journal of Experimental Botany》 2025年第7期2033-2054,共22页
Plant diseases are a major threat that can severely impact the production of agriculture and forestry.This can lead to the disruption of ecosystem functions and health.With its ability to capture continuous narrow-ban... Plant diseases are a major threat that can severely impact the production of agriculture and forestry.This can lead to the disruption of ecosystem functions and health.With its ability to capture continuous narrow-band spectra,hyperspectral technology has become a crucial tool to monitor crop diseases using remote sensing.However,existing continuous wavelet analysis(CWA)methods suffer from feature redundancy issues,while the continuous wavelet projection algorithm(CWPA),an optimization approach for feature selection,has not been fully validated to monitor plant diseases.This study utilized rice bacterial leaf blight(BLB)as an example by evaluating the performance of four wavelet basis functions-Gaussian2,Mexican hat,Meyer,andMorlet-within theCWAandCWPAframeworks.Additionally,the classification models were constructed using the k-nearest neighbors(KNN),randomforest(RF),and Naïve Bayes(NB)algorithms.The results showed the following:(1)Compared to traditional CWA,CWPA significantly reduced the number of required features.Under the CWPA framework,almost all the model combinations achieved maximum classification accuracy with only one feature.In contrast,the CWA framework required three to seven features.(2)Thechoice of wavelet basis functions markedly affected the performance of themodel.Of the four functions tested,the Meyer wavelet demonstrated the best overall performance in both the CWPA and CWA frameworks.(3)Under theCWPAframework,theMeyer-KNNandMeyer-NBcombinations achieved the highest overall accuracy of 93.75%using just one feature.In contrast,under the CWA framework,the CWA-RF combination achieved comparable accuracy(93.75%)but required six features.This study verified the technical advantages of CWPA for monitoring crop diseases,identified an optimal wavelet basis function selection scheme,and provided reliable technical support to precisely monitor BLB in rice(Oryza sativa).Moreover,the proposed methodological framework offers a scalable approach for the early diagnosis and assessment of plant stress,which can contribute to improved accuracy and timeliness when plant stress is monitored. 展开更多
关键词 HYPERSPECTRAL continuous wavelet analysis continuous wavelet projection algorithm wavelet basis function disease monitoring
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Future of diabetic foot risk: Unveiling predictive continuous glucose monitoring biomarkers
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作者 Haewon Byeon 《World Journal of Diabetes》 2025年第6期13-21,共9页
This study critically analyzes the findings of Geng et al,which investigated the association between continuous glucose monitoring(CGM)metrics and the risk of diabetic foot(DF)in individuals with type 2 diabetes melli... This study critically analyzes the findings of Geng et al,which investigated the association between continuous glucose monitoring(CGM)metrics and the risk of diabetic foot(DF)in individuals with type 2 diabetes mellitus.The study de-monstrated significant associations between lower time in range,higher glycemic risk index,mean blood glucose,and time above range and an increased risk of DF.While acknowledging the study's strengths,such as its large sample size and robust statistical methods,this analysis also highlights its limitations,including its cross-sectional design and reliance on self-reported data.The findings are dis-cussed within the framework of established theories,including the concepts of metabolic memory,the glucocentric paradigm,and the role of inflammation.This analysis emphasizes that a comprehensive approach to glucose management,extending beyond traditional glycated hemoglobin A1c measurements,is crucial for DF risk mitigation.Recognizing the impact of poor adherence and ongoing inflammation,future research should prioritize exploring causal mechanisms,the effectiveness of interventions aimed at improving CGM metrics,and the specific contributions of glucose variability to DF development.In conclusion,these findings strongly support the clinical application of diverse CGM metrics to enhance patient outcomes and effectively manage the risk of DF. 展开更多
关键词 Continuous glucose monitoring Diabetic foot Glycemic variability Time in range Glycemic risk index
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Transcriptomic Analysis of Polygonatum sibiricum in Response to Continuous Cropping Obstacles
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作者 Zhufang WU Yong CHEN 《Agricultural Biotechnology》 2025年第2期6-9,12,共5页
[Objectives]This study was conducted to comprehensively understand the changes in gene expression of plants under environmental stress during different growth and development stages.[Methods]The effects of continuous ... [Objectives]This study was conducted to comprehensively understand the changes in gene expression of plants under environmental stress during different growth and development stages.[Methods]The effects of continuous cropping on the roots and leaves of Polygonatum sibiricum were investigated using transcriptome sequencing.Normally-grown first crop P.sibiricum was used as the control group,while continuous cropping plants served as the treatment group.Transcriptomic differences in roots and leaves under different conditions were compared.[Results]The leaf materials of first crop and continuous cropping P.sibiricum(CCLZ vs FCLZ)showed 21916 differentially expressed genes(DEGs),while the root materials of first crop and continuous cropping P.sibiricum(CCRZ vs FCRZ)exhibited 12726 DEGs(the lowest DEG count)(12726).Among them,1896 DEGs were common.GO enrichment analysis revealed that DEGs were mainly enriched in metabolism,cell wall degradation,and pathogen defense.KEGG enrichment analysis indicated that DEGs in CCLZ vs FCLZ and CCRZ vs FCRZ primarily affected hormone signal transduction and pathogen interaction pathways.[Conclusions]This study preliminarily elucidate the regulatory mechanisms in the roots and leaves of continuous cropping P.sibiricum at the molecular level,providing reference for research on its adaptation to continuous cropping. 展开更多
关键词 Polygonatum sibiricum Continuous cropping obstacle TRANSCRIPTOME Differentially expressed gene functional analysis
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Determination of support mechanical mechanism of pre-stressed expandable props to stope roof in room-and-pillar mining
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作者 LI Kun-meng WANG Yong-jiang +3 位作者 LIU Kai LI Yuan-hui FU Zheng-chun PANG Bo-xue 《Journal of Central South University》 2025年第9期3539-3556,共18页
This study is to determine the support mechanism of pre-stressed expandable props for the stope roof in room- and-pillar mining, which is crucial for maintaining stability and preventing roof collapse in mines. Utiliz... This study is to determine the support mechanism of pre-stressed expandable props for the stope roof in room- and-pillar mining, which is crucial for maintaining stability and preventing roof collapse in mines. Utilizing an engineering case from a gold mine in Dandong, China, a laboratory-based similar test is conducted to extract the actual roof characteristic curve. This test continues until the mining stope collapses due to a U-shaped failure. Concurrently, a semi-theoretical method for obtaining the roof characteristic curve is proposed and verified against the actual curve. The semi-theoretical method calculated that the support force and vertical displacement at the demarcation point between the elastic and plastic zones of the roof characteristic curve are 5.0 MPa and 8.20 mm, respectively, corroborating well with the laboratory-based similar test results of 0.22 MPa and 0.730 mm. The weakening factor for the plastic zone in the roof characteristic curve was semi-theoretically estimated to be 0.75. The intersection between the actual roof characteristic curve and the support characteristic curves of expandable props, natural pillars, and concrete props indicates that the expandable prop is the most effective “yielding support” for the stope roof in room-and-pillar mining. That is, the deformation and failure of the stope roof can be effectively controlled with proper release of roof stress. This study provides practical insights for optimizing support strategies in room-and-pillar mining, enhancing the safety and efficiency of mining operations. 展开更多
关键词 expandable prop room-and-pillar mining complex variable function roof characteristic curve support characteristic curve yielding support
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Continuum of glucose and bone metabolism impairment across autonomous cortisol secretion: A cross-sectional study
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作者 Min-Min Han Xiao-Ming Cao +2 位作者 Zi-Ang Liu Yi Zhang Yun-Feng Liu 《World Journal of Diabetes》 2025年第3期134-145,共12页
BACKGROUND Autonomous cortisol secretion(ACS)is linked to a higher prevalence of metabolic abnormalities and an increased risk of major adverse cardiovascular events.AIM To evaluate glucose and bone metabolism in pati... BACKGROUND Autonomous cortisol secretion(ACS)is linked to a higher prevalence of metabolic abnormalities and an increased risk of major adverse cardiovascular events.AIM To evaluate glucose and bone metabolism in patients with ACS using a continuous glucose monitoring system(CGMS)and dual-energy X-ray absorptiometry(DXA).METHODS Patients diagnosed with ACS,including Cushing syndrome,mild ACS(MACS),and nonfunctional adrenal incidentaloma(NFAI),were recruited for this study.Glucose variability and glycemic status were assessed using CGMS.Regional bone mineral content(BMC),bone mineral density(BMD),and bone area(BA)were evaluated using DXA.CGMS-and DXA-derived parameters were compared across the subgroups of ACS.Correlation analysis was performed to examine relationships between varying degrees of cortisol secretion,measured by cortisol after 1 mg overnight dexamethasone suppression test(DST)or 24-hour urine free cortisol(24h UFC),and CGMS-or DXA-derived parameters.RESULTS A total of 64 patients with ACS were included in this study:19 with Cushing syndrome,11 with MACS,and 34 with NFAI.Glucose variability,time above range(TAR),and time in range(TIR)along with specific areal BMC,BMD,and BA,differed significantly between groups of Cushing syndrome and NFAI.A significant positive correlation was observed between glucose variability or TAR and cortisol after 1 mg overnight DST or 24h UFC.By contrast,TIR,along with regional BMC,BMD,and BA,were negatively correlated with varying degrees of cortisol secretion.CONCLUSION Glucose and bone metabolism impairments are on a continuum alteration from NFAI to MACS and Cushing syndrome.Prompt attention should be given to these patients with ACS,especially those with mild hormone secretion.Parameters of glucose variability and glycemic status along with bone condition in regions rich in cancellous bone will provide valuable information. 展开更多
关键词 Continuous glucose monitoring system Glucose variability Time in range Autonomous cortisol secretion Bone mineral content Bone mineral density Bone area
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BOUNDARY VALUE PROBLEMS OF CONJUGATE AND GENERALIZED K-HOLOMORPHIC FUNCTIONS IN C^(2)
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作者 Yanyan CUI Chaojun WANG +1 位作者 Yonghong XIE Yuying QIAO 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期1837-1852,共16页
In this paper,conjugate k-holomorphic functions and generalized k-holomorphic functions are defined in the two-dimensional complex space,and the corresponding Riemann boundary value problems and the inverse problems a... In this paper,conjugate k-holomorphic functions and generalized k-holomorphic functions are defined in the two-dimensional complex space,and the corresponding Riemann boundary value problems and the inverse problems are discussed on generalized bicylinders.By the characteristics of the corresponding functions and boundary properties of the Cauchy type singular integral operators with conjugate k-holomorphic kernels,the general solutions and special solutions of the corresponding boundary value problems are studied in a detailed fashion,and the integral expressions of the solutions are obtained. 展开更多
关键词 several complex variables k-holomorphic functions partial difference equations polyanalytic functions
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New criteria on the existence and global exponential stability of periodic solutions for quaternion-valued cellular neural networks
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作者 LI Ai-ling ZHOU Zheng ZHANG Zheng-qiu 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第3期523-542,共20页
In this paper,a class of quaternion-valued cellular neural networks(QVCNNS)with time-varying delays are considered.Combining graph theory with the continuation theorem of Mawhin’s coincidence degree theory as well as... In this paper,a class of quaternion-valued cellular neural networks(QVCNNS)with time-varying delays are considered.Combining graph theory with the continuation theorem of Mawhin’s coincidence degree theory as well as Lyapunov functional method,we establish new criteria on the existence and exponential stability of periodic solutions for QVCNNS by removing the assumptions for the boundedness on the activation functions and the assumptions that the values of the activation functions are zero at origin.Hence,our results are less conservative and new. 展开更多
关键词 the existence of periodic solutions exponential stability quaternion-valued cellular neural networks combining graph theory with Mawhin’s continuation theorem of coincidence degree theory Lyapunov function method inequality techniques
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Correlation between heart rate variables and the incidence of cardiovascular adverse events in patients with heart failure
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作者 FU Lan-lan LI Mei-ling +1 位作者 PAN Zhi-qiong ZHOU Jia 《South China Journal of Cardiology》 CAS 2024年第3期135-141,共7页
Background Chronic heart failure(CHF)is the end-stage manifestation and main cause of death of cardiovascular system diseases.Ventricular arrhythmia is a common complication,which can increase myocardial oxygen consum... Background Chronic heart failure(CHF)is the end-stage manifestation and main cause of death of cardiovascular system diseases.Ventricular arrhythmia is a common complication,which can increase myocardial oxygen consumption,aggravate the disease,and even cause sudden death due to malignant arrhythmia.As a quantitative method to evaluate cardiac autonomic nervous function,heart rate variability is non-invasive and reproducible,and can quantify the risk associated with various cardiac and non-cardiac diseases.The purpose of this study was to analyze the correlation between heart rate variability and the incidence of cardiovascular adverse events in patients with heart failure.Methods 80 patients with heart failure who were treated in our hospital from May 2020 to May 2022 were selected as the study objects.After 3 months of follow-up,patients were divided into occurrence group(n=44)and nonoccurrence group(n=36)according to the occurrence of adverse cardiovascular events(angina pectoris,myocardial infarction,arrhythmia).The index of heart rate variability and the indicators of cardiac function in patients with heart failure was analyzed by one-way analysis of variance(ANOVA).The Key indicators of heart rate variability include standard deviation of normal RR interval(SDNN),mean standard deviation of consecutive 5-minute heartbeat interval(SDANN),square root of mean square of difference between adjacent heartbeat intervals(RMSSD),and percentage of RR intervals differing more than 50 ms from the preceding one(PNN50).The indicators of cardiac function include the New York Heart Association(NYHA)functional classification,left ventricular ejection fraction(LVEF),brain natriuretic peptide(BNP)and cardiac troponin I(c Tn I).Multivariate logistic regression was used to analyze the incidence of cardiovascular adverse events in patients with heart failure.Receiver operating characteristic(ROC)curve was used to analyze the predictive value of heart rate variability in patient outcomes.The correlation between heart rate variability and the incidence of cardiovascular adverse events was analyzed by Kendall's tau-b analysis.Results There were significant differences in SDNN,SDANN,RMSSD,PNN50,cardiac function grade,LVEF and BNP level between the two groups(P<0.05).Through logistic regression analysis,SDNN,SDANN,RMSSD and PNN50 were independent predictors for the incidence of cardiovascular adverse events(P<0.05).The areas under curve for SDNN,SDANN,RMSSD,and PNN50 predicting of the incidence of cardiovascular adverse events were 0.732,0.732,0.758,and 0.819 respectively,and the sensitivity was 77.27%,81.81%,75.00%and 65.91%,respectively.The specificity was 61.11%,61.11%,80.56%,83.33%(P<0.05),respectively.Through Kendall's tau-b analysis,the index of heart rate variability was negatively correlated with the incidence of adverse cardiovascular events in patients with prognosis(P<0.05).Conclusions Heart rate variability has predictive value for the incidence of adverse cardiovascular events in patients with heart failure.The lower the heart rate variability,the higher incidence of cardiovascular adverse events.[S Chin J Cardiol 2024;25(3):135-141] 展开更多
关键词 Heart rate variability Heart failure Cardiovascular events Cardiac function
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The Determination Method of Product Engineering Features Based on Linguistic Variables
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作者 Guo Mao 《Journal of World Architecture》 2024年第1期18-23,共6页
To overcome the problem of imprecise and unclear information in the development of quality functions,a method for determining the priority of engineering features based on mixed linguistic variables is proposed.First,... To overcome the problem of imprecise and unclear information in the development of quality functions,a method for determining the priority of engineering features based on mixed linguistic variables is proposed.First,the evaluation member uses the determined linguistic variable to give the correlation strength evaluation matrix of customer requirements and engineering features.Secondly,the relative importance of the evaluation member and customer requirements are aggregated.Finally,the priority of engineering features is obtained by calculating the deviation.The feasibility and practicability of this method are proven by taking the design of a new product of a long bag low-pressure pulse dust collector as an example. 展开更多
关键词 Quality function deployment Engineering features Linguistic variable Priority ratings
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