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Association of tumor budding with clinicopathological features and prognostic value in stage III-IV colorectal cancer 被引量:1
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作者 Yue-Hao Luo Zhe-Cheng Yan +7 位作者 Jia-Ying Liu Xin-Yi Li Ming Yang Jun Fan Bo Huang Cheng-Gong Ma Xiao-Na Chang Xiu Nie 《World Journal of Gastroenterology》 SCIE CAS 2024年第2期158-169,共12页
BACKGROUND Tumor budding(TB)has emerged as a promising independent prognostic biomarker in colorectal cancer(CRC).The prognostic role of TB has been extensively studied and currently affects clinical decision making i... BACKGROUND Tumor budding(TB)has emerged as a promising independent prognostic biomarker in colorectal cancer(CRC).The prognostic role of TB has been extensively studied and currently affects clinical decision making in patients with stage I and II CRC.However,existing prognostic studies on TB in stage III CRC have been confined to small retrospective cohort studies.Consequently,this study investigated the correlation among TB categories,clinicopathological features,and prognosis in stage III-IV CRC to further enhance the precision and individualization of treatment through refined prognostic risk stratification.AIM To analyze the relationship between TB categories and clinicopathological characteristics and assess their prognostic value in stage III-IV CRC to further refine the prognostic risk stratification of stage III-IV CRC.METHODS The clinical data of 547 CRC patients were collected for this retrospective study.Infiltration at the front edge of the tumor buds was counted according to the 2016 International Tumor Budding Consensus Conference guidelines.RESULTS Multivariate Cox proportional hazards regression analysis demonstrated that chemotherapy(P=0.004),clinical stage IV(P<0.001),≥4 regional lymph node metastases(P=0.004),left-sided colonic cancer(P=0.040),and Bd 2-3(P=0.002)were independent prognostic factors in patients with stage III-IV CRC.Moreover,the density of tumor infiltrating lymphocytes was higher in Bd 1 than in Bd 2-3,both in the tumor stroma and its invasive margin.CONCLUSION TB has an independent predictive prognostic value in patients with stage III-IV CRC.It is recommended to complete the TB report of stage III-IV CRC cases in the standardized pathological report to further refine risk stratification. 展开更多
关键词 Tumor budding Tumor infiltrating lymphocytes Colorectal cancer Survival analysis PROGNOSIS
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Mathematical Modeling of Cell Polarity Establishment of Budding Yeast
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作者 Yue Liu Jun Xie +1 位作者 Hay-Oak Park Wing-Cheong Lo 《Communications on Applied Mathematics and Computation》 EI 2024年第1期218-235,共18页
The budding yeast Saccharomyces cerevisiae is a powerful model system for studying the cell polarity establishment.The cell polarization process is regulated by signaling molecules,which are initially distributed in t... The budding yeast Saccharomyces cerevisiae is a powerful model system for studying the cell polarity establishment.The cell polarization process is regulated by signaling molecules,which are initially distributed in the cytoplasm and then recruited to a proper location on the cell membrane in response to spatial cues or spontaneously.Polarization of these signaling molecules involves complex regulation,so the mathematical models become a useful tool to investigate the mechanism behind the process.In this review,we discuss how mathematical modeling has shed light on different regulations in the cell polarization.We also propose future applications for the mathematical modeling of cell polarization and morphogenesis. 展开更多
关键词 budding yeast CDC42 MORPHOGENESIS SEPTIN Mathematical models
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Ultra Reliable Load-Aware Connection Management(LACM)Algorithm in WIA-FA Systems
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作者 Liu Gang Jiang Chunhao +3 位作者 Ren Xiaochun Fan Pingzhi Liang Chengchao Ma Zheng 《China Communications》 SCIE CSCD 2024年第8期142-161,共20页
The increasing demand for industrial automation and intelligence has put forward higher requirements for the reliability of industrial wireless communication technology.As an international standard based on 802.11,Wir... The increasing demand for industrial automation and intelligence has put forward higher requirements for the reliability of industrial wireless communication technology.As an international standard based on 802.11,Wireless networks for Industrial Automation-Factory Automation(WIA-FA)greatly improves the reliability in factory automation scenarios by Time Division Multiple Access(TDMA).However,in ultra-dense WIA-FA networks with mobile users,the basic connection management mechanism is inefficient.Most of the handover and resource management algorithms are all based on frequency division multiplexing,not suitable for the TDMA in the WIA-FA network.Therefore,we propose Load-aware Connection Management(LACM)algorithm to adjust the linkage and balance the load of access devices to avoid blocking and improve the reliability of the system.And then we simulate the algorithm to find the optimal settings of the parameters.After comparing with other existing algorithms,the result of the simulation proves that LACM is more efficient in reliability and maintains high reliability of more than 99.8%even in the ultra-dense moving scenario with 1500 field devices.Besides,this algorithm ensures that only a few signaling exchanges are required to ensure load bal-ancing,which is no more than 5 times,and less than half of the best state-of-the-art algorithm. 展开更多
关键词 connection management load-aware multi-connectivity reliability RETRANSMISSION WIAFA
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Seismic fragility analysis of three-tower cable-stayed bridges with different connection configurations
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作者 Chen Chen Liu Jinlong +1 位作者 Lin Junqi Li Suchao 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第4期1009-1027,共19页
Seismic fragility analysis of three-tower cable-stayed bridges with three different structural systems,including rigid system(RS),floating system(FS),and passive energy dissipation system(PEDS),is conducted to study t... Seismic fragility analysis of three-tower cable-stayed bridges with three different structural systems,including rigid system(RS),floating system(FS),and passive energy dissipation system(PEDS),is conducted to study the effects of connection configurations on seismic responses and fragilities.Finite element models of bridges are established using OpenSees.A new ground motion screening method based on the statistical characteristic of the predominant period is proposed to avoid irregular behavior in the selection process of ground motions,and incremental dynamic analysis(IDA)is performed to develop components and systems fragility curves.The effects of damper failure on calculated results for PEDS are examined in terms of seismic response and fragility analysis.The results show that the bridge tower is the most affected component by different structural systems.For RS,the fragility of the middle tower is significantly higher than other components,and the bridge failure starts from the middle tower,exhibiting a characteristic of local failure.For FS and PEDS,the fragility of the edge tower is higher than the middle tower.The system fragility of RS is higher than FS and PEDS.Taking the failure of dampers into account is necessary to obtain reliable seismic capacity of cable-stayed bridges. 展开更多
关键词 seismic fragility cable-stayed bridge connection configuration viscous damper comparison analysis
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The Gut Brain Connection
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作者 Saeed Alzubide Muslih Alhalafi 《Journal of Behavioral and Brain Science》 2024年第3期103-117,共15页
The gut-brain connection is a bidirectional communication system that links the gut microbiome to the central nervous system (CNS). The gut-brain axis communicates through a variety of mechanisms, including the releas... The gut-brain connection is a bidirectional communication system that links the gut microbiome to the central nervous system (CNS). The gut-brain axis communicates through a variety of mechanisms, including the release of hormones, neurotransmitters, and cytokines. These signaling molecules can travel from the gut to the brain and vice versa, influencing various physiological and cognitive functions. Emerging therapeutic strategies targeting the gut-brain connection include probiotics, prebiotics, and faecal microbiota transplantation (FMT). Probiotics are live microorganisms that are similar to the beneficial bacteria that are naturally found in the gut. Prebiotics are non-digestible fibers that feed the beneficial bacteria in the gut. FMT is a procedure in which faecal matter from a healthy donor is transplanted into the gut of a person with a diseased microbiome. Probiotics, prebiotics, and FMT have been shown to be effective in treating a variety of gastrointestinal disorders, and there is growing evidence that they may also be effective in treating neurological and psychiatric disorders. This review explores the emerging field of the gut-brain connection, focusing on the communication pathways between the gut microbiome and the central nervous system. We summarize the potential roles of gut dysbiosis in various neurological and psychiatric disorders. Additionally, we discuss potential therapeutic strategies, research limitations, and future directions in this exciting area of research. More research is needed to fully understand the mechanisms underlying the gut-brain connection and to develop safe and effective therapies that target this pathway. However, the findings to date are promising, and there is the potential to revolutionize the way we diagnose and treat a variety of neurological and psychiatric disorders. 展开更多
关键词 Gut-Brain connection Gut-Brain Axis Enteric Nervous System Microbiota NEUROTRANSMITTERS Neuroinflammation and Mental Health
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Prognostic significance of tumor budding,desmoplastic reaction,and lymphocytic infiltration in patients with gastric adenocarcinoma
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作者 Aysen Yavuz Kubra Simsek +6 位作者 Anil Alpsoy Busra Altunay Elif Ocak Gedik Betul Unal Cumhur Ibrahim Bassorgun Ali Murat Tatli Gulsum Ozlem Elpek 《World Journal of Gastrointestinal Pathophysiology》 2024年第1期9-25,共17页
BACKGROUND Recent studies have shown that the tumor microenvironment significantly influences the behavior of solid tumors.In this context,Accumulated data suggests that pathological evaluation of tumor budding(TB),de... BACKGROUND Recent studies have shown that the tumor microenvironment significantly influences the behavior of solid tumors.In this context,Accumulated data suggests that pathological evaluation of tumor budding(TB),desmoplastic reaction(DR),and tumor-infiltrating lymphocytes(TILs)may be crucial in determining tumor behavior in the gastrointestinal tract.Regarding gastric adenocarcinoma(GAC),although some results suggest that TB and TILs may be effective in determining the course of the disease,the data do not agree.Moreover,very few studies have investigated the relationship between DR and survival.At present,the associations between tumor TB,DR and TILs in GAC patients have not been determined.AIM To establish the relationships between TB,DR,and TILs in patients with GAC and to assess their influence on prognosis.METHODS Our study group comprised 130 patients diagnosed with GAC.The definition of TB was established based on the International TB Consensus Conference.The DR was categorized into three groups according to the level of tumor stroma maturation.The assessment of TILs was conducted using a semiquantitative approach,employing a cutoff value of 5%.The statistical analysis of the whole group and 100 patients with an intestinal subtype of GAC was performed using SPSS version 27.RESULTS A significant correlation between peritumoral budding(PTB)and intratumoral budding(ITB)was noted(r=0.943).Tumors with high PTBs and ITBs had a greater incidence of immature DRs and low TILs(P<0.01).PTB and ITB were associated with histological subtype,lymph node metastasis(LNM),and stage(P<0.01).ITB,PTB,LNM,DR,and stage were significant risk factors associated with poor prognosis.The multivariate Cox regression analysis identified ITB,PTB,and LNM as independent prognostic variables(P<0.05).In intestinal-type adenocarcinomas,a positive correlation between PTB and ITB was noted(r=0.972).While univariate analysis revealed that LNM,stage,PTB,ITB,and DR were strong parameters for predicting survival(P<0.05),only PTB and ITB were found to be independent prognostic factors(P<0.001).CONCLUSION TB may be a potential prognostic marker in GAC.However,further studies are needed to delineate its role in pathology reporting protocols and the predictive effects of DR and TILs. 展开更多
关键词 Gastric cancer Tumor budding Desmoplastic stroma Tumor-infiltrating lymphocytes PROGNOSIS
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Electromechanical Transient Modeling Analysis of Large-Scale New Energy Grid Connection
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作者 Shichao Cao Yonggang Dong Xiaoying Liu 《Energy Engineering》 EI 2024年第4期1109-1125,共17页
The synchronous virtual machine uses inverter power to imitate the performance of the conventional synchronous machine.It also has the same inertia,damping,frequency,voltage regulation,and other external performance a... The synchronous virtual machine uses inverter power to imitate the performance of the conventional synchronous machine.It also has the same inertia,damping,frequency,voltage regulation,and other external performance as the generator.It is the key technology to realize new energy grid connections’stable and reliable operation.This project studies a dynamic simulation model of an extensive new energy power system based on the virtual synchronous motor.A new energy storage method is proposed.The mathematical energy storage model is established by combining the fixed rotor model of a synchronous virtual machine with the charge-discharge power,state of charge,operation efficiency,dead zone,and inverter constraint.The rapid conversion of energy storage devices absorbs the excess instantaneous kinetic energy caused by interference.The branch transient of the critical cut set in the system can be confined to a limited area.Thus,the virtual synchronizer’s kinetic and potential energy can be efficiently converted into an instantaneous state.The simulation of power system analysis software package(PSASP)verifies the correctness of the theory and algorithm in this paper.This paper provides a theoretical basis for improving the transient stability of new energy-connected power grids. 展开更多
关键词 New energy grid connection transient electromechanical modeling synchronous virtual machine PSASP software energy storage
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Multiscale Characteristics and Connection Mechanisms of Attraction Networks:A Trajectory Data Mining Approach Leveraging Geotagged Data
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作者 JIANG Hongqiang WEI Ye +1 位作者 MEI Lin WANG Zhaobo 《Chinese Geographical Science》 SCIE CSCD 2024年第3期533-547,共15页
Urban tourism is considered a complex system,and multiscale exploration of the organizational patterns of attraction networks has become a topical issue in urban tourism,so exploring the multiscale characteristics and... Urban tourism is considered a complex system,and multiscale exploration of the organizational patterns of attraction networks has become a topical issue in urban tourism,so exploring the multiscale characteristics and connection mechanisms of attraction networks is important for understanding the linkages between attractions and even the future destination planning.This paper uses geotagging data to compare the links between attractions in Beijing,China during four different periods:the pre-Olympic period(2004–2007),the Olympic Games and subsequent‘heat period’(2008–2013),the post-Olympic period(2014–2019),and the COVID-19(Corona Virus Disease 2019)pandemic period(2020–2021).The aim is to better understand the evolution and patterns of attraction networks at different scales in Beijing and to provide insights for tourism planning in the destination.The results show that the macro,meso-,and microscales network characteristics of attraction networks have inherent logical relationships that can explain the commonalities and differences in the development process of tourism networks.The macroscale attraction network degree Matthew effect is significant in the four different periods and exhibits a morphological monocentric structure,suggesting that new entrants are more likely to be associated with attractions that already have high value.The mesoscale links attractions according to the common purpose of tourists,and the results of the community segmentation of the attraction networks in the four different periods suggest that the functional polycentric structure describes their clustering effect,and the weak links between clusters result from attractions bound by incomplete information and distance,and the functional polycentric structure with a generally more efficient network of clusters.The pattern structure at the microscale reveals the topological transformation relationship of the regional collaboration pattern,and the attraction network structure in the four different periods has a very similar importance profile structure suggesting that the attraction network has the same construction rules and evolution mechanism,which aids in understanding the attraction network pattern at both macro and micro scales.Important approaches and practical implications for planners and managers are presented. 展开更多
关键词 attraction network travel mobility polycentric structure network motif connectivity mechanism destination management organization(DMO) destination planning Beijing China
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Smart Connection
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作者 ZHAO YANG 《ChinAfrica》 2024年第10期48-49,共2页
Digital services stand out at this year’s China International Fair for Trade in Services.Visitors gathered around a large screen displaying scenes from the video game Black Myth:Wukong,China’s first AAA title,where ... Digital services stand out at this year’s China International Fair for Trade in Services.Visitors gathered around a large screen displaying scenes from the video game Black Myth:Wukong,China’s first AAA title,where they learnt that the monkey king can move with lifelike fluidity,performing seamless actions,thanks to Virtual Motion’s state-of-the-art motion capture technology. 展开更多
关键词 connection SERVICES SERVICES
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Cost Optimization of Steel Beam-to-Column Connections using AVOA
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作者 Ziyu Wang Zhaoyang Ren 《Journal of Architectural Research and Development》 2024年第2期18-23,共6页
The joint-bolt-African Vulture optimization algorithm(AVOA)model is proposed for the design of building connections to improve the stability of steel beam-to-column connections.For this algorithm,the type of steel is ... The joint-bolt-African Vulture optimization algorithm(AVOA)model is proposed for the design of building connections to improve the stability of steel beam-to-column connections.For this algorithm,the type of steel is first determined,and the number of bolts needed by the corresponding steel type is referenced in Eurocode 3.Then,the bearing capacity of the joint can be calculated.The joint-bolt-AVOA model is established by substituting the bolt number required by the steel into the algorithm to obtain the optimal bolt number required while ensuring joint stability.The results show that the number of bolts required by the joint-bolt-AVOA model based on the stability of steel is lower than that calculated by Eurocode 3.Therefore,AVOA can effectively optimize the number of bolts needed in building connections and save resources. 展开更多
关键词 Steel connections African vulture optimization algorithm Optimization of bolts
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Artificial intelligence-based comprehensive analysis of immune-stemness-tumor budding profile to predict survival of patients with pancreatic adenocarcinoma 被引量:2
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作者 Tianxing Zhou Quan Man +9 位作者 Xueyang Li Yongjie Xie Xupeng Hou Hailong Wang Jingrui Yan Xueqing Wei Weiwei Bai Ziyun Liu Jing Liu Jihui Hao 《Cancer Biology & Medicine》 SCIE CAS CSCD 2023年第3期196-217,共22页
Objective:Pancreatic ductal adenocarcinoma(PDAC)is an aggressive malignancy.CD8^(+)T cells,cancer stem cells(CSCs),and tumor budding(TB)have been significantly correlated with the outcome of patients with PDAC,but the... Objective:Pancreatic ductal adenocarcinoma(PDAC)is an aggressive malignancy.CD8^(+)T cells,cancer stem cells(CSCs),and tumor budding(TB)have been significantly correlated with the outcome of patients with PDAC,but the correlations have been independently reported.In addition,no integrated immune-CSC-TB profile for predicting survival in patients with PDAC has been established.Methods:Multiplexed immunofluorescence and artificial intelligence(AI)-based comprehensive analyses were used for quantification and spatial distribution analysis of CD8^(+)T cells,CD133^(+)CSCs,and TB.In vivo humanized patient-derived xenograft(PDX)models were established.Nomogram analysis,calibration curve,time-dependent receiver operating characteristic curve,and decision curve analyses were performed using R software.Results:The established‘anti-/pro-tumor’models showed that the CD8^(+)T cell/TB,CD8^(+)T cell/CD133^(+)CSC,TB-adjacent CD8^(+)T cell,and CD133^(+)CSC-adjacent CD8^(+)T cell indices were positively associated with survival of patients with PDAC.These findings were validated using PDX-transplanted humanized mouse models.An integrated nomogram-based immune-CSC-TB profile that included the CD8^(+)T cell/TB and CD8^(+)T cell/CD133^(+)CSC indices was established and shown to be superior to the tumor-nodemetastasis stage model in predicting survival of patients with PDAC.Conclusions:‘Anti-/pro-tumor’models and the spatial relationship among CD8^(+)T cells,CSCs,and TB within the tumor microenvironment were investigated.Novel strategies to predict the prognosis of patients with PDAC were established using AI-based comprehensive analysis and machine learning workflow.The nomogram-based immune-CSC-TB profile can provide accurate prognosis prediction for patients with PDAC. 展开更多
关键词 Artificial intelligence CD8 CSCs tumor budding PDAC NOMOGRAM
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Tumor budding as a potential prognostic marker in determining the behavior of primary liver cancers 被引量:1
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作者 Betul Unal Mennan Yigitcan Celik +2 位作者 Elif Ocak Gedik Cumhur Ibrahim Bassorgun Gulsum Ozlem Elpek 《World Journal of Hepatology》 2023年第6期775-785,共11页
Hepatocellular(HCC)and intrahepatic cholangiocarcinoma(ICC),the most common primary tumors of the liver,are among the most important causes of cancer deaths worldwide.Because patients with primary liver tumors are fre... Hepatocellular(HCC)and intrahepatic cholangiocarcinoma(ICC),the most common primary tumors of the liver,are among the most important causes of cancer deaths worldwide.Because patients with primary liver tumors are frequently diagnosed at an advanced stage and have high mortality,many efforts have been made to identify new markers to determine their behavior and treatment,similar to those in other solid organ tumors.Recently,morphological assessment of tumor budding(TB)has been revealed as a promising prognostic finding to predict tumor behavior and survival across several different tumor types.Currently,the TB score in colorectal cancer has been revealed as an important parameter in pathology report protocols to determine the course of the disease.Regarding the liver,despite enormous data showing that many mechanisms involved in TB are associated with tumor behavior in both HCC and ICC,studies focusing on the role of TB in predicting the behavior and prognosis of these tumors have started to be investigated very recently.The purpose of this review is to present data about TB in primary tumors of the liver,pointing out the potential role of this parameter in determining the course of the disease,and emphasize the need to increase the number of further studies focusing on the evaluation of this parameter with an overview of the mechanisms involved in TB. 展开更多
关键词 Tumor budding Hepatocellular carcinoma CHOLANGIOCARCINOMA PROGNOSIS Liver cancer Epithelial-mesenchymal transition
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Tumor budding in gastric cancer 被引量:1
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作者 Shuo-Meng Xiao Jian Li 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第4期578-591,共14页
The tumor,nodes,metastasis(TNM)staging system has long been the gold standard for the classification and prognosis of solid tumors.However,the TNM staging system is not without limitations.Prognostic heterogeneity exi... The tumor,nodes,metastasis(TNM)staging system has long been the gold standard for the classification and prognosis of solid tumors.However,the TNM staging system is not without limitations.Prognostic heterogeneity exists within patients at the same stage.Therefore,the pursuit of other biomarkers with the potential to classify patients with cancer has never stopped.One of them,tumor budding(TB),has gained much success in colorectal cancer.In recent years,TB in gastric cancer has attracted much attention from researchers,beginning to reveal the molecular and biological aspects of this phenomenon in gastric cancer,and has emerged as a promising prognostic biomarker in gastric cancer,predicting disease progression and unfavorable survival.Therefore,it is time and essential to provide a holistic overview of TB in gastric cancer,which has not been achieved and is the aim of this review. 展开更多
关键词 Tumor budding Gastric cancer Poorly differentiated cluster PROGNOSIS Lymph node metastasis
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Topological Aspects of Dendrimers via Connection-Based Descriptors 被引量:1
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作者 Muhammad Javaid Ahmed Alamer Aqsa Sattar 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第5期1649-1667,共19页
Topological indices(TIs)have been practiced for distinct wide-ranging physicochemical applications,especially used to characterize and model the chemical structures of various molecular compounds such as dendrimers,na... Topological indices(TIs)have been practiced for distinct wide-ranging physicochemical applications,especially used to characterize and model the chemical structures of various molecular compounds such as dendrimers,nanotubes and neural networks with respect to their certain properties such as solubility,chemical stability and low cytotoxicity.Dendrimers are prolonged artificially synthesized or amalgamated natural macromolecules with a sequential layer of branches enclosing a central core.A present-day trend in mathematical and computational chemistry is the characterization of molecular structure by applying topological approaches,including numerical graph invariants.Among topological descriptors,Zagreb connection indices(ZCIs)have much importance.This manuscript involves the establishment of general results to calculate ZCIs,namely first ZCI(FZCI),second ZCI(SZCI),third ZCI(TZCI),modified FZCI,modified SZCI and modified TZCI of two special types of dendrimers nanostars,namely,poly propylene imine octamin(PPIO)dendrimer and poly(propyl)ether imine(PPEtIm)dendrimer.Furthermore,we provide the numerical and graphical comparative analysis of our calculated results for both types of dendrimers with each other. 展开更多
关键词 Zagreb indices zagreb connection indices topological index dendrimer nanostars
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Age-related hearing loss accelerates the decline in fast speech comprehension and the decompensation of cortical network connections 被引量:2
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作者 He-Mei Huang Gui-Sheng Chen +10 位作者 Zhong-Yi Liu Qing-Lin Meng Jia-Hong Li Han-Wen Dong Yu-Chen Chen Fei Zhao Xiao-Wu Tang Jin-Liang Gao Xi-Ming Chen Yue-Xin Cai Yi-Qing Zheng 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第9期1968-1975,共8页
Patients with age-related hearing loss face hearing difficulties in daily life.The causes of age-related hearing loss are complex and include changes in peripheral hearing,central processing,and cognitive-related abil... Patients with age-related hearing loss face hearing difficulties in daily life.The causes of age-related hearing loss are complex and include changes in peripheral hearing,central processing,and cognitive-related abilities.Furthermore,the factors by which aging relates to hearing loss via changes in audito ry processing ability are still unclear.In this cross-sectional study,we evaluated 27 older adults(over 60 years old) with age-related hearing loss,21 older adults(over 60years old) with normal hearing,and 30 younger subjects(18-30 years old) with normal hearing.We used the outcome of the uppe r-threshold test,including the time-compressed thres h old and the speech recognition threshold in noisy conditions,as a behavioral indicator of auditory processing ability.We also used electroencephalogra p hy to identify presbycusis-related abnormalities in the brain while the participants were in a spontaneous resting state.The timecompressed threshold and speech recognition threshold data indicated significant diffe rences among the groups.In patients with age-related hearing loss,information masking(babble noise) had a greater effect than energy masking(speech-shaped noise) on processing difficulties.In terms of resting-state electroencephalography signals,we observed enhanced fro ntal lobe(Brodmann’s area,BA11) activation in the older adults with normal hearing compared with the younger participants with normal hearing,and greater activation in the parietal(BA7) and occipital(BA19) lobes in the individuals with age-related hearing loss compared with the younger adults.Our functional connection analysis suggested that compared with younger people,the older adults with normal hearing exhibited enhanced connections among networks,including the default mode network,sensorimotor network,cingulo-opercular network,occipital network,and frontoparietal network.These results suggest that both normal aging and the development of age-related hearing loss have a negative effect on advanced audito ry processing capabilities and that hearing loss accele rates the decline in speech comprehension,especially in speech competition situations.Older adults with normal hearing may have increased compensatory attentional resource recruitment represented by the to p-down active listening mechanism,while those with age-related hearing loss exhibit decompensation of network connections involving multisensory integration. 展开更多
关键词 age-related hearing loss aging ELECTROENCEPHALOGRAPHY fast-speech comprehension functional brain network functional connectivity restingstate SLORETA source analysis speech reception threshold
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改进RRT-Connect与DWA算法的巡检机器人路径规划研究
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作者 罗征志 韩怡可 +1 位作者 张鑫 邹宇博 《计算机工程与应用》 CSCD 北大核心 2024年第15期344-354,共11页
针对传统RRT-Connect算法在密集复杂环境中路径规划效率低、动态避障效果差等问题,提出一种改进RRT-Connect与DWA融合算法。该算法通过改进采样策略、动态步长优化和碰撞检测引导随机树生长;在随机树中采用贪心策略和角度约束优化路径... 针对传统RRT-Connect算法在密集复杂环境中路径规划效率低、动态避障效果差等问题,提出一种改进RRT-Connect与DWA融合算法。该算法通过改进采样策略、动态步长优化和碰撞检测引导随机树生长;在随机树中采用贪心策略和角度约束优化路径。基于巡检机器人建立运动学模型,通过速度采样空间生成轨迹簇;建立模糊逻辑系统自适应调整DWA算法评价函数的权重系数,将全局最优路径点融入DWA算法中实现全局最优路径和实时避障。仿真结果表明,在油气站场密集复杂环境中,改进RRT-Connect算法较传统算法路径缩短约27.09%,平滑度提高约84.6%,碰撞距离提高约18.75%;改进融合算法路径减少约2.97%,平滑度提高约78.8%,碰撞距离提高约30.6%,验证了提出算法的有效性。 展开更多
关键词 路径规划 改进RRT-connect算法 DWA算法 融合算法
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基于改进RRT-Connect算法的全局路径规划
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作者 朱建军 王明森 《组合机床与自动化加工技术》 北大核心 2024年第4期52-55,61,共5页
针对RRT-Connect算法在复杂环境内的路径规划中存在探索性弱、收敛速度慢、冗余节点多、搜索路径较长等问题,提出一种改进的RRT-Connect算法。通过引入高质量随机点和动态步长的方法,提高了生成随机树的质量并减少了冗余节点数量;采用... 针对RRT-Connect算法在复杂环境内的路径规划中存在探索性弱、收敛速度慢、冗余节点多、搜索路径较长等问题,提出一种改进的RRT-Connect算法。通过引入高质量随机点和动态步长的方法,提高了生成随机树的质量并减少了冗余节点数量;采用正向寻优和逆向贪婪的方式,改善了搜索路径较长的问题。实验结果表明,改进RRT-Connect算法平均路径规划时间缩短26.41%,平均路径规划长度缩短19.05%,平均路径规划节点个数减少41.91%,证明了改进RRT-Connect算法相比于原算法规划效率更高,规划时间更少,规划路径质量更优。 展开更多
关键词 路径规划 RRT-connect算法 动态步长 轨迹优化 贪婪算法 3次B样条曲线
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Analytical Investigation into the Rotational Performance of Glulam Bolted Beam-Column Connections under Coupled Bending Moment and Shear Force
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作者 Xiaofeng Zhang Lisheng Luo +2 位作者 Youfu Sun Xinyue Cui Yongqiang Zhang 《Journal of Renewable Materials》 SCIE EI 2023年第4期2033-2054,共22页
Considering the glulam beam-column connection form and the number of bolts,monotonic loading test and finite element analysis was carried out on 9 connection specimens in 3 groups to study the rotational performance a... Considering the glulam beam-column connection form and the number of bolts,monotonic loading test and finite element analysis was carried out on 9 connection specimens in 3 groups to study the rotational performance and failure mode of the connection.The test results revealed that compared with U-shaped connectors,T-shaped connectors can effectively improve the ductility of connections,and the increase in the number of bolts can reduce the initial stiffness and ductility of connections.By theoretical analysis,formulas for calculating the initial stiffness and ultimate moment of connections were deduced.Subsequently,the moment-rotation theoretical model of connections was established based on the formulas,which were validated according to the test data and simulation results.The proposed model can not only improve the current theoretical system of heavy-duty glulam beam-column structure but also provide a theoretical basis for calculating the mechanical properties of the glulam beam-column connection. 展开更多
关键词 Beam-column connection mechanical properties STIFFNESS ultimate moment
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Ensuring Secure Platooning of Constrained Intelligent and Connected Vehicles Against Byzantine Attacks:A Distributed MPC Framework 被引量:1
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作者 Henglai Wei Hui Zhang +1 位作者 Kamal AI-Haddad Yang Shi 《Engineering》 SCIE EI CAS CSCD 2024年第2期35-46,共12页
This study investigates resilient platoon control for constrained intelligent and connected vehicles(ICVs)against F-local Byzantine attacks.We introduce a resilient distributed model-predictive platooning control fram... This study investigates resilient platoon control for constrained intelligent and connected vehicles(ICVs)against F-local Byzantine attacks.We introduce a resilient distributed model-predictive platooning control framework for such ICVs.This framework seamlessly integrates the predesigned optimal control with distributed model predictive control(DMPC)optimization and introduces a unique distributed attack detector to ensure the reliability of the transmitted information among vehicles.Notably,our strategy uses previously broadcasted information and a specialized convex set,termed the“resilience set”,to identify unreliable data.This approach significantly eases graph robustness prerequisites,requiring only an(F+1)-robust graph,in contrast to the established mean sequence reduced algorithms,which require a minimum(2F+1)-robust graph.Additionally,we introduce a verification algorithm to restore trust in vehicles under minor attacks,further reducing communication network robustness.Our analysis demonstrates the recursive feasibility of the DMPC optimization.Furthermore,the proposed method achieves exceptional control performance by minimizing the discrepancies between the DMPC control inputs and predesigned platoon control inputs,while ensuring constraint compliance and cybersecurity.Simulation results verify the effectiveness of our theoretical findings. 展开更多
关键词 Model predictive control Resilient control Platoon control Intelligent and connected vehicle Byzantine attacks
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Effects of connection types and elevated temperature on the impact behaviour of restrained beam in portal steel frame
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作者 Yu-Xu Guo Feng Xi +2 位作者 Ying-Hua Tan Feng Liu Ya-Chao Hu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第7期174-191,共18页
Based on the background of structural protection and Disaster Reduction Engineering, the dynamic behaviour and failure mechanism of restrained beams in portal steel frames in localised fire are investigated via experi... Based on the background of structural protection and Disaster Reduction Engineering, the dynamic behaviour and failure mechanism of restrained beams in portal steel frames in localised fire are investigated via experimental measurement and numerical simulation techniques. Comprehensive parametric studies are carried out to discuss the influence of end connection types, temperature, impact velocity,impact mass and span-to-depth ratio(SDR) on the dynamic response of the beams. The characteristics of deformation, internal force and energy distribution about the restrained beams and its joints are investigated. A temperature dependent criterion for evaluating the frame joint performance is proposed to measure the degree of performance degradation and impact resistance of the joint. The dynamic displacement amplification factor in different temperature environments are proposed for the different beam end constraint types and SDRs. Results of the experimental and numerical analysis show that the welded connection(WC) of three typical joint types is the strongest, and the extended endplate connection(EEC) is the weakest in terms of the impact resistance performance. With regard to the failure mode of the joint, the failure positions of the WC and the welded-bolted connection are located in the inner web of the column. Meanwhile, the EEC is located in the connection position between the beam and the endplate. Three different internal force stages and two obvious critical temperature boundaries of the restrained beams emerge with the increase in temperature, and they have significant characteristics in terms of deformation trend, internal force transfer and energy distribution. During the impact, a phenomenon known as “compression arch action” develops into “catenary action” with the increase in deflection in the frame beam mechanism. 展开更多
关键词 Restrained beam connection Temperature Impact Failure modes Internal force mechanism
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