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Variations in leaf functional traits among plant species grouped by growth and leaf types in Zhenjiang,China 被引量:12
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作者 Congyan Wang Jiawei Zhou +2 位作者 Hongguang Xiao Jun Liu Lei Wang 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第2期241-248,共8页
Leaf functional traits are adaptations that enable plants to live under various environmental conditions. This study aims to determine the differences in leaf functional traits among plants grouped by growth habit, le... Leaf functional traits are adaptations that enable plants to live under various environmental conditions. This study aims to determine the differences in leaf functional traits among plants grouped by growth habit, leaf life span,leaf lifestyle, leaf form, and origin. Specific leaf area(SLA) of perennial or evergreen species was lower than that of annual or deciduous species because longer-lived leaves of perennial or evergreen species require more investment in structural integrity and/or defense against disturbances, especially with any resource constraint. SLA of large individuals was lower than that of small individuals. The low SLA in large individuals can improve their response to changing light and water conditions because increasing plant height is advantageous for light competition, but it can also impose a cost in terms of structural support and water transport. Petioles of plants with compound leaves were significantly longer than those of simple leaves because branching is expensive in terms of gaining height. SLA of plants increased with increasing invasiveness accordingly, and SLA of invasive plants was higher than that of their native congeners because invasive plants should invest more biomass on leaf growth rather than leaf structures per unit area to achieve a higher growth rate.Overall, variation in leaf functional traits among different groups may play an adaptive role in the successful survival of plants under diverse environments because leaf functional traits can lead to pronounced effects on leaf function,especially the acquisition and use of light. Plant species with different growth and leaf traits balance resource acquisition and leaf construction to minimize trade-offs and achieve fitness advantages in their natural habitat. 展开更多
关键词 expensive enable constraint perennial advantageous fitness grouped environments minimize habitat
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Anomalies of Precursory Group and Grouped Strong Earthquakes in the Sichuan-Yunnan Region 被引量:2
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作者 ShiShaoxian ChengWanzheng 《Earthquake Research in China》 2004年第4期348-356,共9页
Three methods of extracting the information of anomalies of a precursory group are put forward, i.e., the mathematical analyses of the synthetic information of earthquake precursors (S), the inhomogeneous degree of pr... Three methods of extracting the information of anomalies of a precursory group are put forward, i.e., the mathematical analyses of the synthetic information of earthquake precursors (S), the inhomogeneous degree of precursory groups (ID) and the values of short-term and impending anomaly in near-source area (NS). Using these methods, we calculate the observational data of deformation, underground fluid and hydrochemical constituents obtained from different seismic stations in the Sichuan-Yunnan region and conclude that the synthetic precursory anomalies of a single strong earthquake with M S6.0 differ greatly from those of the grouped strong earthquakes, for the anomalous information of precursory groups are more abundant. The three methods of extracting the synthetic precursory anomaly and the related numerical results can be applied into the practice of prediction to the grouped strong earthquakes in the Sichuan-Yunnan region. Inhomogeneous degree (ID) of synthetic precursory anomaly can be identified automatically because it takes the threshold of distributive characteristics of the anomalies of precursory group as its criterion for anomaly. 展开更多
关键词 Anomalies of precursory group Synthetic information Short-term and impending characteristic anomaly in the near-source area Prediction of the grouped strong earthquakes
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STATISTICAL INFERENCE FOR A BIVARIATE EXPONENTIAL DISTRIBUTION BASED ON GROUPED DATA
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作者 YE CINAN(Department of Applied Mathematics, Naming University of Science & Tech.nology, Naming210014.) 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1996年第3期285-294,共10页
Consider the bivariate exponential distribution due to Marshall and Olkin[2], whose survival function is F(x, g) = exp[-λ1x-λ2y-λ12 max(x, y)] (x 0,y 0)with unknown Parameters λ1 > 0, λ2 > 0 and λ12 0.Base... Consider the bivariate exponential distribution due to Marshall and Olkin[2], whose survival function is F(x, g) = exp[-λ1x-λ2y-λ12 max(x, y)] (x 0,y 0)with unknown Parameters λ1 > 0, λ2 > 0 and λ12 0.Based on grouped data, a newestimator for λ1, λ2 and λ12 is derived and its asymptotic properties are discussed.Besides, some test procedures of equal marginals and independence are given. Asimulation result is given, too. 展开更多
关键词 Bivariate exponential distribution parameter estimation grouped data asymptoticproperty.
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On the Power Performance of Test Statistics for the Generalized Rayleigh Interval Grouped Data
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作者 Hatim Solayman Migdadi 《Open Journal of Statistics》 2015年第5期474-482,共9页
In this paper, the weighted Kolmogrov-Smirnov, Cramer von-Miss and the Anderson Darling test statistics are considered as goodness of fit tests for the generalized Rayleigh interval grouped data. An extensive simulati... In this paper, the weighted Kolmogrov-Smirnov, Cramer von-Miss and the Anderson Darling test statistics are considered as goodness of fit tests for the generalized Rayleigh interval grouped data. An extensive simulation process is conducted to evaluate their controlling of type 1 error and their power functions. Generally, the weighted Kolmogrov-Smirnov test statistics show a relatively better performance than both, the Cramer von-Miss and the Anderson Darling test statistics. For large sample values, the Anderson Darling test statistics cannot control type 1 error but for relatively small sample values it indicates a better performance than the Cramer von-Miss test statistics. Best selection of the test statistics and highlights for future studies are also explored. 展开更多
关键词 GENERALIZED RAYLEIGH Distribution INTERVAL grouped Data GOODNESS of FIT Tests Empirical Type 1 ERROR Power Function
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Study of Paleoearthquakes by Excavation of Grouped Trenches on the Zemuhe Fault in Daqingliangzi,Xichang,Sichuan
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作者 Tian Qinjian Ren Zhikun Zhang Junlong 《Earthquake Research in China》 2009年第1期56-67,共12页
Uncertainties are common in the dating of paleoearthquakes.To improve the credibility of the dating of paleoearthquakes,analysis was done on fault activity,sedimentary environment and seismo-geomorphology to investiga... Uncertainties are common in the dating of paleoearthquakes.To improve the credibility of the dating of paleoearthquakes,analysis was done on fault activity,sedimentary environment and seismo-geomorphology to investigate paleoearthquakes along the Zemuhe active fault zone.Grouped trenches were excavated near Daqingliangzi,which revealed three palaeoearthquake events aged 160a,3100a and 5500a~8900a,respectively,including recurrence intervals of about 3000a.Sedimentary processes related to strike-slip fault type earthquakes were discussed,and a sedimentary model was put forward for strike-slip faults at hillsides where drumlin and reverse scarp developed. 展开更多
关键词 Palaeoearthquake grouped trenches Micro-geomorphology Zemuhe River sedimentary model
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Network autoregression model with grouped factor structures
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作者 ZHANG Zhiyuan ZHU Xuening 《中山大学学报(自然科学版)(中英文)》 CAS CSCD 北大核心 2023年第5期24-37,共14页
Network autoregression and factor model are effective methods for modeling network time series data.In this study,we propose a network autoregression model with a factor structure that incorporates a latent group stru... Network autoregression and factor model are effective methods for modeling network time series data.In this study,we propose a network autoregression model with a factor structure that incorporates a latent group structure to address nodal heterogeneity within the network.An iterative algorithm is employed to minimize a least-squares objective function,allowing for simultaneous estimation of both the parameters and the group structure.To determine the unknown number of groups and factors,a PIC criterion is introduced.Additionally,statistical inference of the estimated parameters is presented.To assess the validity of the proposed estimation and inference procedures,we conduct extensive numerical studies.We also demonstrate the utility of our model using a stock dataset obtained from the Chinese A-Share stock market. 展开更多
关键词 network autoregression factor structure HETEROGENEITY latent group structure network time series
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Novel Grouped Probability Data Association Algorithm for MIMO Detection
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作者 车文 赵慧 王文博 《Journal of Beijing Institute of Technology》 EI CAS 2008年第1期67-70,共4页
To bridge the performance gap between original probability data association (PDA) algorithm and the optimum maximum a posterior (MAP) algorithm for multi-input multi-output (MIMO) detection, a grouped PDA (GP-... To bridge the performance gap between original probability data association (PDA) algorithm and the optimum maximum a posterior (MAP) algorithm for multi-input multi-output (MIMO) detection, a grouped PDA (GP-PDA) detection algorithm is proposed. The proposed GP-PDA method divides all the transmit antennas into groups, and then updates the symbol probabilities group by group using PDA computations. In each group, joint a posterior probability (APP) is computed to obtain the APP of a single symbol in this group, like the MAP algorithm. Such new algorithm combines the characters of MAP and PDA. MAP and original PDA algorithm can be regarded as a special case of the proposed GP-PDA. Simulations show that the proposed GP-PDA provides a performance and complexity trade, off between original PDA and MAP algorithm. 展开更多
关键词 multi-input multi-output (MIMO) V-BLAST GROUP probability data association (PDA)
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Calculating the upper bound of the Gini coefficient using grouped data and a case study of China
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作者 Pixu Shi Anru R.Zhang 《Science China Mathematics》 2025年第10期2501-2518,共18页
Determining an upper bound,particularly the optimal upper bound of the Gini coefficient when dealing with grouped data without specified income brackets remains an important and open question.In this paper,we introduc... Determining an upper bound,particularly the optimal upper bound of the Gini coefficient when dealing with grouped data without specified income brackets remains an important and open question.In this paper,we introduce an efficient algorithm to calculate the exact optimal upper bound of the Gini coefficient with provable guarantees.To exemplify these methods,we also offer computed results for the Gini coefficients of urban and rural China spanning the years 2003 to 2008. 展开更多
关键词 Gini coefficient grouped data of income upper bound China
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商业银行基于Group Training技术的小样本学习应用研究
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作者 吴永飞 寿弘宇 +3 位作者 王彦博 魏文术 徐奇 张月 《金融科技时代》 2025年第3期16-22,共7页
人工智能是推动社会进步和经济发展的关键力量。商业银行已经在诸多业务领域广泛使用人工智能技术,如精准营销、智能风控、智慧运营等业务领域。然而,有些业务场景在“冷启动”阶段面临样本量不足,并且坏样本量极少的小样本学习问题,这... 人工智能是推动社会进步和经济发展的关键力量。商业银行已经在诸多业务领域广泛使用人工智能技术,如精准营销、智能风控、智慧运营等业务领域。然而,有些业务场景在“冷启动”阶段面临样本量不足,并且坏样本量极少的小样本学习问题,这导致现有的人工智能技术可能失效。基于此,文章创新提出了一种Group Training(群组训练)建模思路,可以有效解决小样本学习问题。实证结果表明,Group Training建模方案在多个金融数据集上效果均明显优于传统的建模方案,这为商业银行小样本学习提供了新的研究思路和解决方案。 展开更多
关键词 人工智能 小样本学习 Group Learning Group Training
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改进infoGAN和QPSO-VGG16的小样本条件下电机轴承故障诊断方法
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作者 刘航 张德春 +3 位作者 刘志坚 何蔚 陶韵旭 孟欣雨 《电机与控制学报》 北大核心 2025年第5期167-178,共12页
针对电机轴承故障数据相对于正常数据稀缺的现状,本文提出改进infoGAN和QPSO-VGG16的故障诊断方法。首先采用连续小波变换(CWT)方法将高维故障振动信号转换为对应二维时频图,构建原始图像数据集。建立基于条件信息最大化生成对抗网络(ci... 针对电机轴承故障数据相对于正常数据稀缺的现状,本文提出改进infoGAN和QPSO-VGG16的故障诊断方法。首先采用连续小波变换(CWT)方法将高维故障振动信号转换为对应二维时频图,构建原始图像数据集。建立基于条件信息最大化生成对抗网络(cinfoGAN)的数据增强模型,在统一的框架下完成所有类别故障数据的生成,提升数据增强工作的质量和效率。进一步,构建基于VGG16网络的故障诊断模型,在交替使用原始和增强图像数据集对VGG16网络进行训练的过程中,通过改进的粒子群优化(QPSO)算法对2类数据集的学习率进行联合寻优,确保VGG16网络达到最佳的性能。在真实的电机轴承振动信号上开展数值实验结果表明,将振动信号转换为图像能够充分发挥VGG16模型对图像数据的特征提取能力,且数据增强和交替训练方法能够使故障诊断的准确率依次提升2.6%和4.5%。 展开更多
关键词 电机轴承 故障诊断 连续小波变换 生成对抗网络 Visual Geometry Group 16
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Regulating the“core-shell”microstructure of hard carbon through sodium hydroxide activation for achieving high-capacity SIBs anode 被引量:3
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作者 Haihua Wang Huizhu Niu +6 位作者 Kewei Shu Liyu Sun Yu Wang Yifan Du Yun Han Cunguo Yang Yong-Mook Kang 《Journal of Materials Science & Technology》 2025年第6期161-170,共10页
Pore structure engineering has been acknowledged as suitable approach to creating active sites and en-hancing ion transport capabilities of hard carbon anodes.However,conventional porous carbon materials exhibit high ... Pore structure engineering has been acknowledged as suitable approach to creating active sites and en-hancing ion transport capabilities of hard carbon anodes.However,conventional porous carbon materials exhibit high BET and surface defects.Additionally,the sodium storage mechanism predominantly occurs in the slope region.This contradicts practical application requirements because the capacity of the plateau region is crucial for determining the actual capacity of batteries.In our work,we prepared a novel“core-shell”carbon framework(CNA1200).Introducingclosedporesand carboxylgroupsinto coal-basedcarbon materials to enhance its sodium storage performance.The closed pore structure dominates in the“core”structure,which is attributed to the timely removal of sodium hydroxide(NaOH)to prevent further for-mation of active carbon structure.The presence of closed pores is beneficial for increasing sodium ion storage in the low-voltage plateau region.And the“shell”structure originates from coal tar pitch,it not only uniformly connects hard carbon particles together to improve cycling stability,but is also rich in carboxyl groups to enhance the reversible sodium storage performance in slope region.CNA1200 has ex-cellent electrochemical performance,it exhibits a specific capacity of 335.2 mAh g^(−1)at a current density of 20 mA g^(−1)with ICE=51.53%.In addition,CNA1200 has outstanding cycling stability with a capac-ity retention of 91.8%even when cycling over 200 times.When CNA1200 is used as anode paired with Na_(3)V_(2)(PO_(4))_(3)cathode,it demonstrates a capacity of 109.54 mAh g^(−1)at 0.1 C and capacity retention of 94.64%at 0.5 C.This work provides valuable methods for regulating the structure of sodium-ion battery(SIBs)anode and enhances the potential for commercialization. 展开更多
关键词 Hard carbon plateau region NaOH controlled etching-thermal annealing Closed pore structure Carboxyl groups Coal-based carbon materials
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Insights into recent advancements in human and animal rotavirus vaccines:Exploring new frontiers 被引量:2
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作者 Ahmed H.Ghonaim Sherin R.Rouby +6 位作者 Wedad M.Nageeb Ashraf Ahmed Elgendy Rong Xu Changsheng Jiang Noha H.Ghonaim Qigai He Wentao Li 《Virologica Sinica》 2025年第1期1-14,共14页
Rotavirus infections cause severe gastroenteritis and dehydration in young children and animals worldwide,leading to high rates of morbidity and mortality,predominantly in low-and middleincome countries.In the past de... Rotavirus infections cause severe gastroenteritis and dehydration in young children and animals worldwide,leading to high rates of morbidity and mortality,predominantly in low-and middleincome countries.In the past decade,substantial progress has been made in the development and implementation of rotavirus vaccines,which have been essential in alleviating the global burden of this disease,not only in human being but also in livestock species like calves and piglets,where these infections can cause significant economic losses.By synthesizing the latest research and real-world evidence,this review article is designated to provide deep insights into the current state of rotavirus vaccine technology and its global implementation as well as the application of rotavirus vaccines in veterinary settings and their importance in controlling zoonotic transmission and maintaining food security. 展开更多
关键词 Group A rotavirus Childhood diarrhea Domestic animals Rotavirus vaccines One health
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Interannual succession of phytoplankton community in a canyon-shaped drinking water reservoir during the initial impoundment period:Taxonomic versus functional groups 被引量:1
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作者 Yi Hou Ya Cheng +6 位作者 Kai Li Meng Yang Kangzhe Huang Gang Ji Ruikang Xue Tinglin Huang Gang Wen 《Journal of Environmental Sciences》 2025年第5期454-468,共15页
During the initial impoundment period of a canyon-shaped reservoir,the water body fluctuated violently regarding water level,hydrological condition,and thermal stratification.These variations may alter the structure o... During the initial impoundment period of a canyon-shaped reservoir,the water body fluctuated violently regarding water level,hydrological condition,and thermal stratification.These variations may alter the structure of phytoplankton community,resulting in algal blooms and seriously threatening the ecological security of the reservoir.It is of great significance to understand the continuous changes of phytoplankton in the initial impoundment period for the protection of reservoir water quality.Therefore,a two-year in-situ monitoring study was conducted on water quality and phytoplankton in a representative canyonshaped reservoir named Sanhekou and the interannual changes of phytoplankton community and its response to environmental changes during the initial impoundment period were discussed at taxonomic versus functional classification levels.The results showed that the total nitrogen and permanganate index levels were relatively high in the first year due to rapid water storage and heavy rainfall input,and the more stable hydrological conditions in the second year promoted the increase of algae density and the transformation of community,and the proportion of cyanobacteria increased significantly.The succession order of phytoplankton in the first year of the initial impoundment periodwas Chlorophyta-Bacillariophyta-Chlorophyta,or J/F/X1-P/MP/W1-A/X1/MP,respectively.And the succession order in the second year was Cyanobacteria/Chlorophyta-Bacillariophyta-Chlorophyta,or L_(M)/G/P-P/A/X1-X1/J/G.Water temperature,relativewater column stability,mixing depth,and pHwere crucial factors affecting phytoplankton community succession.This study revealed the interannual succession law and driving factors of phytoplankton in the initial impoundment period and provided an important reference for the operation management and ecological protection of canyon-shaped reservoirs. 展开更多
关键词 Canyon-shaped reservoir Functional groups Initial impoundment Interannual succession Water quality
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Operando quantitatively analyses of polarizations in all-vanadium flow batteries 被引量:1
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作者 Zhenyu Wang Jing Sun +8 位作者 Jiadong Shen Zixiao Guo Xiaosa Xu Jin Li Jiayou Ren Yiju Li Tianshuai Wang Xinzhuang Fan Tianshou Zhao 《Journal of Energy Chemistry》 2025年第6期178-184,I0005,共8页
All-vanadium flow batteries(VFBs)are one of the most promising large-scale energy storage technologies.Conducting an operando quantitative analysis of the polarizations in VFBs under different conditions is essential ... All-vanadium flow batteries(VFBs)are one of the most promising large-scale energy storage technologies.Conducting an operando quantitative analysis of the polarizations in VFBs under different conditions is essential for developing high power density batteries.Here,we employ an operando decoupling method to quantitatively analyze the polarizations in each electrochemical and chemical reaction of VFBs under different catalytic conditions.Results show that the reduction reaction of V^(3+)presents the largest activation polarization,while the reduction reaction of VO_(2)^(+)primarily contributes to concentration polarizations due to the formation of the intermediate product V_(2)O_(3)^(3+).Additionally,it is found that the widely used electrode catalytic methods,incorporating oxygen functional groups and electrodepositing Bi,not only enhance the reaction kinetics but also exacerbate concentration polarizations simultaneously,especially during the discharge process.Specifically,in the battery with the high oxygen-containing electrodes,the negative side still accounts for the majority of activation loss(75.3%)at 200 mA cm^(-2),but it comes down to 36,9% after catalyzing the negative reactions with bismuth.This work provides an effective way to probe the limiting steps in flow batteries under various working conditions and offers insights for effectively enhancing battery performance for future developments. 展开更多
关键词 Vanadium flow battery Quantitative analysis Polarization Oxygen functional groups BISMUTH
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An Improved Practical Byzantine Fault-Tolerant Algorithm Based on XGBoost Grouping for Consortium Chains
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作者 Xiaowei Wang Haiyang Zhang +5 位作者 Jiasheng Zhang Yingkai Ge Kexin Cui Zifu Peng Zhengyi Li Lihua Wang 《Computers, Materials & Continua》 SCIE EI 2025年第1期1295-1311,共17页
In response to the challenges presented by the unreliable identity of the master node,high communication overhead,and limited network support size within the Practical Byzantine Fault-Tolerant(PBFT)algorithm for conso... In response to the challenges presented by the unreliable identity of the master node,high communication overhead,and limited network support size within the Practical Byzantine Fault-Tolerant(PBFT)algorithm for consortium chains,we propose an improved PBFT algorithm based on XGBoost grouping called XG-PBFT in this paper.XG-PBFT constructs a dataset by training important parameters that affect node performance,which are used as classification indexes for nodes.The XGBoost algorithm then is employed to train the dataset,and nodes joining the system will be grouped according to the trained grouping model.Among them,the nodes with higher parameter indexes will be assigned to the consensus group to participate in the consensus,and the rest of the nodes will be assigned to the general group to receive the consensus results.In order to reduce the resource waste of the system,XG-PBFT optimizes the consensus protocol for the problem of high complexity of PBFT communication.Finally,we evaluate the performance of XG-PBFT.The experimental results show that XG-PBFT can significantly improve the performance of throughput,consensus delay and communication complexity compared to the original PBFT algorithm,and the performance enhancement is significant compared to other algorithms in the case of a larger number of nodes.The results demonstrate that the XG-PBFT algorithm is more suitable for large-scale consortium chains. 展开更多
关键词 Consortium chain PBFT GROUPING REPUTATION XGBoost
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Efficacy of combined psychological and physical nursing in preventing peripherally inserted central catheter-related thrombosis in gastric cancer patients 被引量:1
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作者 Wei-Jing Ni Yu-Xiu Xi Yong-Chao Zhou 《World Journal of Gastrointestinal Surgery》 2025年第3期206-212,共7页
BACKGROUND Long-term chemotherapy for patients with gastric cancer(GC),facilitated by peripherally inserted central catheter(PICC)catheterization,reduces vascular damage and enhances drug delivery efficiency but carri... BACKGROUND Long-term chemotherapy for patients with gastric cancer(GC),facilitated by peripherally inserted central catheter(PICC)catheterization,reduces vascular damage and enhances drug delivery efficiency but carries risks of catheter-related complications.A combination of group psychological nursing and physical mo-vement care significantly mitigates the risk of venous thrombosis and improves psychological well-being,and enhances motor function,underscoring its clinical importance.AIM To assess group psychological and physical movement nursing in preventing venous thrombosis in patients with PICC GC.METHODS Sixty-five GC patients with PICC,admitted from January 2022 to January 2023,were randomly divided into two groups using the lottery method:A control group(n=35,routine nursing)and an observation group(n=30,routine nursing plus psychological nursing and physical movement nursing).Both groups re-ceived continuous care for 2 weeks.Pre-nursing and post-nursing data on psycho-logical state,physical function,chemotherapy-related thrombosis incidence,and cancer-related fatigue were analyzed using SPSS 26.0 and GraphPad Prism 8.0.RESULTS After nursing,both groups showed reduced Hamilton Anxiety Scale scores and increased General Perceived Self-Efficacy Scale scores,with the observation group performing better(P<0.05).The Functional Comprehensive Assessment score for the observation group after nursing was(65.42±2.35)points,lower than the control group’s(62.19±4.33)points(P<0.05).Although no significant difference was observed in the incidence of venous thrombosis between the two groups(χ2=0.815,P=0.367),the observation group had lower incidence.Both groups showed decreased Revised Piper Fatigue Scale scores,with the observation group scoring lower(P<0.05).CONCLUSION Group psychological and physical movement nursing for patients with PICC reduces venous thrombosis risk,improves psychological well-being,cancer-related fatigue,and physical function,making it highly promotable. 展开更多
关键词 Group psychological nursing Physical movement nursing Peripherally inserted central catheter Gastric cancer Venous thrombosis Cancer-related fatigue
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Dynamics of a Stochastic Epidemic Model with Age-group
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作者 LAN Xiaomin CHEN Guangmin +5 位作者 ZHOU Ruiyang ZHENG Kuicheng CAI Shaojian WEI Fengying JIN Zhen MAO Xuerong 《应用数学》 北大核心 2025年第1期294-307,共14页
A stochastic epidemic model with two age groups is established in this study,in which the susceptible(S),the exposed(E),the infected(I),the hospitalized(H)and the recovered(R)are involved within the total population,t... A stochastic epidemic model with two age groups is established in this study,in which the susceptible(S),the exposed(E),the infected(I),the hospitalized(H)and the recovered(R)are involved within the total population,the aging rates between two age groups are set to be constant.The existence-and-uniqueness of global positive solution is firstly showed.Then,by constructing several appropriate Lyapunov functions and using the high-dimensional Itô’s formula,the sufficient conditions for the stochastic extinction and stochastic persistence of the exposed individuals and the infected individuals are obtained.The stochastic extinction indicator and the stochastic persistence indicator are less-valued expressions compared with the basic reproduction number.Meanwhile,the main results of this study are modified into multi-age groups.Furthermore,by using the surveillance data for Fujian Provincial Center for Disease Control and Prevention,Fuzhou COVID-19 epidemic is chosen to carry out the numerical simulations,which show that the age group of the population plays the vital role when studying infectious diseases. 展开更多
关键词 Epidemic model Age groups PERSISTENCE EXTINCTION
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Medical Diagnosis Based on Multi-Attribute Group Decision-Making Using Extension Fuzzy Sets,Aggregation Operators and Basic Uncertainty Information Granule
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作者 Anastasios Dounis Ioannis Palaiothodoros Anna Panagiotou 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期759-811,共53页
Accurate medical diagnosis,which involves identifying diseases based on patient symptoms,is often hindered by uncertainties in data interpretation and retrieval.Advanced fuzzy set theories have emerged as effective to... Accurate medical diagnosis,which involves identifying diseases based on patient symptoms,is often hindered by uncertainties in data interpretation and retrieval.Advanced fuzzy set theories have emerged as effective tools to address these challenges.In this paper,new mathematical approaches for handling uncertainty in medical diagnosis are introduced using q-rung orthopair fuzzy sets(q-ROFS)and interval-valued q-rung orthopair fuzzy sets(IVq-ROFS).Three aggregation operators are proposed in our methodologies:the q-ROF weighted averaging(q-ROFWA),the q-ROF weighted geometric(q-ROFWG),and the q-ROF weighted neutrality averaging(qROFWNA),which enhance decision-making under uncertainty.These operators are paired with ranking methods such as the similarity measure,score function,and inverse score function to improve the accuracy of disease identification.Additionally,the impact of varying q-rung values is explored through a sensitivity analysis,extending the analysis beyond the typical maximum value of 3.The Basic Uncertain Information(BUI)method is employed to simulate expert opinions,and aggregation operators are used to combine these opinions in a group decisionmaking context.Our results provide a comprehensive comparison of methodologies,highlighting their strengths and limitations in diagnosing diseases based on uncertain patient data. 展开更多
关键词 Medical diagnosis multi-attribute group decision-making(MAGDM) q-ROFS IVq-ROFS BUI aggregation operators similarity measures inverse score function
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High mobility group box 1 in the central nervous system:regeneration hidden beneath inflammation
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作者 Hanki Kim Bum Jun Kim +4 位作者 Seungyon Koh Hyo Jin Cho Xuelian Jin Byung Gon Kim Jun Young Choi 《Neural Regeneration Research》 SCIE CAS 2025年第1期107-115,共9页
High-mobility group box 1 was first discovered in the calf thymus as a DNA-binding nuclear protein and has been widely studied in diverse fields,including neurology and neuroscience.High-mobility group box 1 in the ex... High-mobility group box 1 was first discovered in the calf thymus as a DNA-binding nuclear protein and has been widely studied in diverse fields,including neurology and neuroscience.High-mobility group box 1 in the extracellular space functions as a pro-inflammatory damage-associated molecular pattern,which has been proven to play an important role in a wide variety of central nervous system disorders such as ischemic stroke,Alzheimer’s disease,frontotemporal dementia,Parkinson’s disease,multiple sclerosis,epilepsy,and traumatic brain injury.Several drugs that inhibit high-mobility group box 1 as a damage-associated molecular pattern,such as glycyrrhizin,ethyl pyruvate,and neutralizing anti-high-mobility group box 1 antibodies,are commonly used to target high-mobility group box 1 activity in central nervous system disorders.Although it is commonly known for its detrimental inflammatory effect,high-mobility group box 1 has also been shown to have beneficial pro-regenerative roles in central nervous system disorders.In this narrative review,we provide a brief summary of the history of high-mobility group box 1 research and its characterization as a damage-associated molecular pattern,its downstream receptors,and intracellular signaling pathways,how high-mobility group box 1 exerts the repair-favoring roles in general and in the central nervous system,and clues on how to differentiate the pro-regenerative from the pro-inflammatory role.Research targeting high-mobility group box 1 in the central nervous system may benefit from differentiating between the two functions rather than overall suppression of high-mobility group box 1. 展开更多
关键词 central nervous system damage-associated molecular pattern ethyl pyruvate glycyrhizzin high mobility group box 1 INFLAMMATION neural stem cells NEURODEVELOPMENT oligodendrocyte progenitor cells redox status REGENERATION
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On Markov and Zariski Embeddings in a Free Group
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作者 Victor Hugo Yanez Dmitri Shakhmatov 《南开大学学报(自然科学版)》 北大核心 2025年第1期18-21,共4页
Let G be a group.The family of all sets which are closed in every Hausdorf group topology of G form the family of closed sets of a T_(1) topology M_(G) on G called the Markov topology.Similarly,the family of all algeb... Let G be a group.The family of all sets which are closed in every Hausdorf group topology of G form the family of closed sets of a T_(1) topology M_(G) on G called the Markov topology.Similarly,the family of all algebraic subsets of G forms a family of closed sets for another T_(1)topology Z_(G) on G called the Zarski topology.A subgroup H of G is said to be Markov(resp.Zarski)embedded if the equality M_(G|H)=M_(H)(resp.Z_(G|H)=Z_(H))holds.I's proved that an abirary subgroup of a free group is both Zariski and Markov embedded in it. 展开更多
关键词 free group Zariski topology Markov embedding centralizer in a free group
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