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A novel method for clustering cellular data to improve classification
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作者 Diek W.Wheeler Giorgio A.Ascoli 《Neural Regeneration Research》 SCIE CAS 2025年第9期2697-2705,共9页
Many fields,such as neuroscience,are experiencing the vast prolife ration of cellular data,underscoring the need fo r organizing and interpreting large datasets.A popular approach partitions data into manageable subse... Many fields,such as neuroscience,are experiencing the vast prolife ration of cellular data,underscoring the need fo r organizing and interpreting large datasets.A popular approach partitions data into manageable subsets via hierarchical clustering,but objective methods to determine the appropriate classification granularity are missing.We recently introduced a technique to systematically identify when to stop subdividing clusters based on the fundamental principle that cells must differ more between than within clusters.Here we present the corresponding protocol to classify cellular datasets by combining datadriven unsupervised hierarchical clustering with statistical testing.These general-purpose functions are applicable to any cellular dataset that can be organized as two-dimensional matrices of numerical values,including molecula r,physiological,and anatomical datasets.We demonstrate the protocol using cellular data from the Janelia MouseLight project to chara cterize morphological aspects of neurons. 展开更多
关键词 cellular data clustering dendrogram data classification Levene's one-tailed statistical test unsupervised hierarchical clustering
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Exosomes originating from neural stem cells undergoing necroptosis participate in cellular communication by inducing TSC2 upregulation of recipient cells following spinal cord injury
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作者 Shiming Li Jianfeng Li +5 位作者 Guoliang Chen Tao Lin Penghui Zhang Kuileung Tong Ningning Chen Shaoyu Liu 《Neural Regeneration Research》 SCIE CAS 2025年第11期3273-3286,共14页
We previously demonstrated that inhibiting neural stem cells necroptosis enhances functional recovery after spinal cord injury.While exosomes are recognized as playing a pivotal role in neural stem cells exocrine func... We previously demonstrated that inhibiting neural stem cells necroptosis enhances functional recovery after spinal cord injury.While exosomes are recognized as playing a pivotal role in neural stem cells exocrine function,their precise function in spinal cord injury remains unclear.To investigate the role of exosomes generated following neural stem cells necroptosis after spinal cord injury,we conducted singlecell RNA sequencing and validated that neural stem cells originate from ependymal cells and undergo necroptosis in response to spinal cord injury.Subsequently,we established an in vitro necroptosis model using neural stem cells isolated from embryonic mice aged 16-17 days and extracted exosomes.The results showed that necroptosis did not significantly impact the fundamental characteristics or number of exosomes.Transcriptome sequencing of exosomes in necroptosis group identified 108 differentially expressed messenger RNAs,104 long non-coding RNAs,720 circular RNAs,and 14 microRNAs compared with the control group.Construction of a competing endogenous RNA network identified the following hub genes:tuberous sclerosis 2(Tsc2),solute carrier family 16 member 3(Slc16a3),and forkhead box protein P1(Foxp1).Notably,a significant elevation in TSC2 expression was observed in spinal cord tissues following spinal cord injury.TSC2-positive cells were localized around SRY-box transcription factor 2-positive cells within the injury zone.Furthermore,in vitro analysis revealed increased TSC2 expression in exosomal receptor cells compared with other cells.Further assessment of cellular communication following spinal cord injury showed that Tsc2 was involved in ependymal cellular communication at 1 and 3 days post-injury through the epidermal growth factor and midkine signaling pathways.In addition,Slc16a3 participated in cellular communication in ependymal cells at 7 days post-injury via the vascular endothelial growth factor and macrophage migration inhibitory factor signaling pathways.Collectively,these findings confirm that exosomes derived from neural stem cells undergoing necroptosis play an important role in cellular communication after spinal cord injury and induce TSC2 upregulation in recipient cells. 展开更多
关键词 cellular communication competing endogenous RNA EXOSOMES Foxp1 NECROPTOSIS neural stem cells Slc16a3 spinal cord injury transcriptome sequencing Tsc2
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Urban growth scenario projection using heuristic cellular automata in arid areas considering the drought impact
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作者 TANG Xiaoyan FENG Yongjiu +7 位作者 LEI Zhenkun CHEN Shurui WANG Jiafeng WANG Rong TANG Panli WANG Mian JIN Yanmin TONG Xiaohua 《Journal of Arid Land》 SCIE CSCD 2024年第4期580-601,共22页
Arid areas with low precipitation and sparse vegetation typically yield compact urban pattern,and drought directly impacts urban site selection,growth processes,and future scenarios.Spatial simulation and projection b... Arid areas with low precipitation and sparse vegetation typically yield compact urban pattern,and drought directly impacts urban site selection,growth processes,and future scenarios.Spatial simulation and projection based on cellular automata(CA)models is important to achieve sustainable urban development in arid areas.We developed a new CA model using bat algorithm(BA)named bat algorithm-probability-of-occurrence-cellular automata(BA-POO-CA)model by considering drought constraint to accurately delineate urban growth patterns and project future scenarios of Urumqi City and its surrounding areas,located in Xinjiang Uygur Autonomous Region,China.We calibrated the BA-POO-CA model for the drought-prone study area with 2000 and 2010 data and validated the model with 2010 and 2020 data,and finally projected its urban scenarios in 2030.The results showed that BA-POO-CA model yielded overall accuracy of 97.70%and figure-of-merits(FOMs)of 35.50%in 2010,and 97.70%and 26.70%in 2020,respectively.The inclusion of drought intensity factor improved the performance of BA-POO-CA model in terms of FOMs,with increases of 5.50%in 2010 and 7.90%in 2020 than the model excluding drought intensity factor.This suggested that the urban growth of Urumqi City was affected by drought,and therefore taking drought intensity factor into account would contribute to simulation accuracy.The BA-POO-CA model including drought intensity factor was used to project two possible scenarios(i.e.,business-as-usual(BAU)scenario and ecological scenario)in 2030.In the BAU scenario,the urban growth dominated mainly in urban fringe areas,especially in the northern part of Toutunhe District,Xinshi District,and Midong District.Using exceptional and extreme drought areas as a spatial constraint,the urban growth was mainly concentrated in the"main urban areas-Changji-Hutubi"corridor urban pattern in the ecological scenario.The results of this research can help to adjust urban planning and development policies.Our model is readily applicable to simulating urban growth and future scenarios in global arid areas such as Northwest China and Africa. 展开更多
关键词 bat algorithm cellular automata(CA) probability-of-occurrence drought intensity algorithm-probability-of-occurrence-cellular automata(BA-POO-CA)model arid areas
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Patient-derived induced pluripotent stem cells with a MERTK mutation exhibit cell junction abnormalities and aberrant cellular differentiation potential
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作者 Hang Zhang Ling-Zi Wu +1 位作者 Zhen-Yu Liu Zi-Bing Jin 《World Journal of Stem Cells》 SCIE 2024年第5期512-524,共13页
BACKGROUND Human induced pluripotent stem cell(hiPSC)technology is a valuable tool for generating patient-specific stem cells,facilitating disease modeling,and invest-igating disease mechanisms.However,iPSCs carrying ... BACKGROUND Human induced pluripotent stem cell(hiPSC)technology is a valuable tool for generating patient-specific stem cells,facilitating disease modeling,and invest-igating disease mechanisms.However,iPSCs carrying specific mutations may limit their clinical applications due to certain inherent characteristics.AIM To investigate the impact of MERTK mutations on hiPSCs and determine whether hiPSC-derived extracellular vesicles(EVs)influence anomalous cell junction and differentiation potential.METHODS We employed a non-integrating reprogramming technique to generate peripheral blood-derived hiPSCs with and hiPSCs without a MERTK mutation.Chromo-somal karyotype analysis,flow cytometry,and immunofluorescent staining were utilized for hiPSC identification.Transcriptomics and proteomics were employed to elucidate the expression patterns associated with cell junction abnormalities and cellular differentiation potential.Additionally,EVs were isolated from the supernatant,and their RNA and protein cargos were examined to investigate the involvement of hiPSC-derived EVs in stem cell junction and differentiation.RESULTS The generated hiPSCs,both with and without a MERTK mutation,exhibited normal karyotype and expressed pluripotency markers;however,hiPSCs with a MERTK mutation demonstrated anomalous adhesion capability and differentiation potential,as confirmed by transcriptomic and proteomic profiling.Furthermore,hiPSC-derived EVs were involved in various biological processes,including cell junction and differentiation.CONCLUSION HiPSCs with a MERTK mutation displayed altered junction characteristics and aberrant differentiation potential.Furthermore,hiPSC-derived EVs played a regulatory role in various biological processes,including cell junction and differentiation. 展开更多
关键词 Cell junction cellular differentiation Extracellular vesicle Human induced pluripotent stem cells TRANSCRIPTOMICS Proteomics
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Shi-pi-xiao-ji formula suppresses hepatocellular carcinoma by reducing cellular stiffness through upregulation of acetyl-coA acetyltransferase 1
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作者 Hui-Ying Jian Zi-Cheng Liang +2 位作者 Huan Wen Zhen Zhang Pu-Hua Zeng 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第6期2727-2741,共15页
BACKGROUND Previous studies have shown that the Shi-pi-xiao-ji(SPXJ)herbal decoction formula is effective in suppressing hepatocellular carcinoma(HCC),but the underlying mechanisms are not known.Therefore,this study i... BACKGROUND Previous studies have shown that the Shi-pi-xiao-ji(SPXJ)herbal decoction formula is effective in suppressing hepatocellular carcinoma(HCC),but the underlying mechanisms are not known.Therefore,this study investigated whether the antitumor effects of the SPXJ formula in treating HCC were mediated by acetyl-coA acetyltransferase 1(ACAT1)-regulated cellular stiffness.Through a series of experiments,we concluded that SPXJ inhibits the progression of HCC by upregulating the expression level of ACAT1,lowering the level of cholesterol in the cell membrane,and altering the cellular stiffness,which provides a new idea for the research of traditional Chinese medicine against HCC.AIM To investigate the anti-tumor effects of the SPXJ formula on the malignant progression of HCC.METHODS HCC cells were cultured in vitro with SPXJ-containing serum prepared by injecting SPXJ formula into wild-type mice.The apoptotic rate and proliferative,invasive,and migratory abilities of control and SPXJ-treated HCC cells were compared.Atomic force microscopy was used to determine the cell surface morphology and the Young’s modulus values of the control and SPXJ-treated HCC cells.Plasma membrane cholesterol levels in HCC cells were detected using the Amplex Red cholesterol detection kit.ACAT1 protein levels were estimated using western blotting.RESULTS Compared with the vehicle group,SPXJ serum considerably reduced proliferation of HCC cells,increased stiffness and apoptosis of HCC cells,inhibited migration and invasion of HCC cells,decreased plasma membrane cholesterol levels,and upregulated ACAT1 protein levels.However,treatment of HCC cells with the water-soluble cholesterol promoted proliferation,migration,and invasion of HCC cells as well as decreased cell stiffness and plasma membrane cholesterol levels,but did not alter the apoptotic rate and ACAT1 protein expression levels compared with the vehicle control.CONCLUSION SPXJ formula inhibited proliferation,invasion,and migration of HCC cells by decreasing plasma membrane cholesterol levels and altering cellular stiffness through upregulation of ACAT1 protein expression. 展开更多
关键词 Shi-pi-xiao-ji formula Hepatocellular carcinoma cellular stiffness Plasma membrane cholesterol level AcetylcoA acetyltransferase 1
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Correlative factors of poor prognosis and abnormal cellular immune function in patients with Alzheimer’s disease 被引量:2
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作者 Hua Bai Hong-Mei Zeng +2 位作者 Qi-Fang Zhang Yue-Zhi Hu Fei-Fei Deng 《World Journal of Clinical Cases》 SCIE 2024年第6期1063-1075,共13页
BACKGROUND Alzheimer’s disease(AD)is a serious disease causing human dementia and social problems.The quality of life and prognosis of AD patients have attracted much attention.The role of chronic immune inflammation... BACKGROUND Alzheimer’s disease(AD)is a serious disease causing human dementia and social problems.The quality of life and prognosis of AD patients have attracted much attention.The role of chronic immune inflammation in the pathogenesis of AD is becoming more and more important.AIM To study the relationship among cognitive dysfunction,abnormal cellular immune function,neuroimaging results and poor prognostic factors in patients.METHODS A retrospective analysis of 62 hospitalized patients clinical diagnosed with AD who were admitted to our hospital from November 2015 to November 2020.Collect cognitive dysfunction performance characteristics,laboratory test data and neuroimaging data from medical records within 24 h of admission,including Mini Mental State Examination Scale score,drawing clock test,blood T lymphocyte subsets,and neutrophils and lymphocyte ratio(NLR),disturbance of consciousness,extrapyramidal symptoms,electroencephalogram(EEG)and head nucleus magnetic spectroscopy(MRS)and other data.Multivariate logistic regression analysis was used to determine independent prog-nostic factors.the modified Rankin scale(mRS)was used to determine whether the prognosis was good.The correlation between drug treatment and prognostic mRS score was tested by the rank sum test.RESULTS Univariate analysis showed that abnormal cellular immune function,extrapyramidal symptoms,obvious disturbance of consciousness,abnormal EEG,increased NLR,abnormal MRS,and complicated pneumonia were related to the poor prognosis of AD patients.Multivariate logistic regression analysis showed that the decrease in the proportion of T lym-phocytes in the blood after abnormal cellular immune function(odd ratio:2.078,95%confidence interval:1.156-3.986,P<0.05)was an independent risk factor for predicting the poor prognosis of AD.The number of days of donepezil treatment to improve cognitive function was negatively correlated with mRS score(r=0.578,P<0.05).CONCLUSION The decrease in the proportion of T lymphocytes may have predictive value for the poor prognosis of AD.It is recommended that the proportion of T lymphocytes<55%is used as the cut-off threshold for predicting the poor prog-nosis of AD.The early and continuous drug treatment is associated with a good prognosis. 展开更多
关键词 Alzheimer’s disease cellular immunity PROGNOSIS T lymphocytes Magnetic resonance spectroscopy
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Global research trends and prospects of cellular metabolism in colorectal cancer 被引量:1
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作者 Yan-Chen Liu Zhi-Cheng Gong +3 位作者 Chao-Qun Li Peng Teng Yan-Yan Chen Zhao-Hui Huang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第2期527-542,共16页
BACKGROUND An increasing number of studies have focused on the role of cellular metabolism in the development of colorectal cancer(CRC).However,no work is currently available to synthesize the field through bibliometr... BACKGROUND An increasing number of studies have focused on the role of cellular metabolism in the development of colorectal cancer(CRC).However,no work is currently available to synthesize the field through bibliometrics.AIM To analyze the development in the field of“glucose metabolism”(GM),“amino acid metabolism”(AM),“lipid metabolism”(LM),and“nucleotide metabolism”(NM)in CRC by visualization.METHODS Articles within the abovementioned areas of GM,AM,LM and NM in CRC,which were published from January 1,1991,to December 31,2022,are retrieved from the Web of Science Core Collection and analyzed by CiteSpace 6.2.R4 and VOSviewer 1.6.19.RESULTS The field of LM in CRC presented the largest number of annual publications and the fastest increase in the last decade compared with the other three fields.Meanwhile,China and the United States were two of the most prominent contri-butors in these four areas.In addition,Gang Wang,Wei Jia,Maria Notar-nicola,and Cornelia Ulrich ranked first in publication numbers,while Jing-Yuan Fang,Senji Hirasawa,Wei Jia,and Charles Fuchs were the most cited authors on average in these four fields,respectively.“Gut microbiota”and“epithelial-mesenchymal transition”emerged as the newest burst words in GM,“gut microbiota”was the latest outburst word in AM,“metastasis”,“tumor microenvironment”,“fatty acid metabolism”,and“metabolic reprogramming”were the up-to-date outbreaking words in LM,while“epithelial-mesenchymal transition”and“apoptosis”were the most recently occurring words in NM.CONCLUSION Research in“cellular metabolism in CRC”is all the rage at the moment,and researchers are particularly interested in exploring the mechanism to explain the metabolic alterations in CRC.Targeting metabolic vulnerability appears to be a promising direction in CRC therapy. 展开更多
关键词 cellular metabolism Colorectal cancer Glucose metabolism Amino acid metabolism Lipid metabolism Nucleotide metabolism
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Cellular Chemical Field and Cellular Homeostasis
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作者 Bin Cong Lu Li +5 位作者 Qian Wang Tao He Junwei Li Hongliang Xie Aolin Zhang Xiaohui Fan 《Engineering》 SCIE EI CAS CSCD 2024年第8期18-24,共7页
1.Introduction Cell structure and function are controlled by a complex regulatory networking process,in which molecular adaptation and interaction are essential to maintain cellular homeostasis following dynamic multi... 1.Introduction Cell structure and function are controlled by a complex regulatory networking process,in which molecular adaptation and interaction are essential to maintain cellular homeostasis following dynamic multi-omics rules and multi-systematic changes.This complex chemical process is an important mechanism for stabilizing the cell microenvironment. 展开更多
关键词 MAINTAIN stabilizing cellular
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In situ visualization of the cellular uptake and sub-cellular distribution of mussel oligosaccharides
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作者 Zhenjie Yu Huarong Shao +7 位作者 Xintian Shao Linyan Yu Yanan Gao Youxiao Ren Fei Liu Caicai Meng Peixue Ling Qixin Chen 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第6期840-850,共11页
Unlike chemosynthetic drugs designed for specific molecular and disease targets,active small-molecule natural products typically have a wide range of bioactivities and multiple targets,necessitating extensive screenin... Unlike chemosynthetic drugs designed for specific molecular and disease targets,active small-molecule natural products typically have a wide range of bioactivities and multiple targets,necessitating extensive screening and development.To address this issue,we propose a strategy for the direct in situ microdynamic examination of potential drug candidates to rapidly identify their effects and mechanisms of action.As a proof-of-concept,we investigated the behavior of mussel oligosaccharide(MOS-1)by tracking the subcellular dynamics of fluorescently labeled MOS-1 in cultured cells.We recorded the entire dynamic process of the localization of fluorescein isothiocyanate(FITC)-MOS-1 to the lysosomes and visualized the distribution of the drug within the cell.Remarkably,lysosomes containing FITC-MOS-1 actively recruited lipid droplets,leading to fusion events and increased cellular lipid consumption.These drug behaviors confirmed MOS-1 is a candidate for the treatment of lipid-related diseases.Furthermore,in a high-fat HepG2 cell model and in high-fat diet-fed apolipoprotein E(ApoE)^(-/-)mice,MOS-1 significantly promoted triglyceride degradation,reduced lipid droplet accumulation,lowered serum triglyceride levels,and mitigated liver damage and steatosis.Overall,our work supports the prioritization of in situ visual monitoring of drug location and distribution in subcellular compartments during the drug development phase,as this methodology contributes to the rapid identification of drug indications.Collectively,this methodology is significant for the screening and development of selective small-molecule drugs,and is expected to expedite the identification of candidate molecules with medicinal effects. 展开更多
关键词 cellular imaging Fluorescence labeling Mussel oligosaccharide Lipid metabolism
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Simulation of Dynamic Recrystallization in 7075 Aluminum Alloy Using Cellular Automaton
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作者 赵晓东 SHI Dongxing +3 位作者 李亚杰 QIN Fengming CHU Zhibing YANG Xiaorong 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第2期425-435,共11页
The evolution of microstructure during hot deformation is key to achieving good mechanical properties in aluminum alloys.We have developed a cellular automaton(CA) based model to simulate the microstructural evolution... The evolution of microstructure during hot deformation is key to achieving good mechanical properties in aluminum alloys.We have developed a cellular automaton(CA) based model to simulate the microstructural evolution in 7075 aluminum alloy during hot deformation.Isothermal compression tests were conducted to obtain material parameters for 7075 aluminum alloy,leading to the establishment of models for dislocation density,nucleation of recrystallized grains,and grain growth.Integrating these aspects with grain topological deformation,our CA model effectively predicts flow stress,dynamic recrystallization(DRX) volume fraction,and average grain size under diverse deformation conditions.A systematic comparison was made between electron back scattered diffraction(EBSD) maps and CA model simulated under different deformation temperatures(573 to 723 K),strain rates(0.001 to 1 s^(-1)),and strain amounts(30% to 70%).These analyses indicate that large strain,high temperature,and low strain rate facilitate dynamic recrystallization and grain refinement.The results from the CA model show good accuracy and predictive capability,with experimental error within 10%. 展开更多
关键词 cellular automaton dynamic recrystallization 7075 aluminum alloy hot compression
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Dynamics analysis and cryptographic implementation of a fractional-order memristive cellular neural network model
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作者 周新卫 蒋东华 +4 位作者 Jean De Dieu Nkapkop Musheer Ahmad Jules Tagne Fossi Nestor Tsafack 吴建华 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期418-433,共16页
Due to the fact that a memristor with memory properties is an ideal electronic component for implementation of the artificial neural synaptic function,a brand-new tristable locally active memristor model is first prop... Due to the fact that a memristor with memory properties is an ideal electronic component for implementation of the artificial neural synaptic function,a brand-new tristable locally active memristor model is first proposed in this paper.Here,a novel four-dimensional fractional-order memristive cellular neural network(FO-MCNN)model with hidden attractors is constructed to enhance the engineering feasibility of the original CNN model and its performance.Then,its hardware circuit implementation and complicated dynamic properties are investigated on multi-simulation platforms.Subsequently,it is used toward secure communication application scenarios.Taking it as the pseudo-random number generator(PRNG),a new privacy image security scheme is designed based on the adaptive sampling rate compressive sensing(ASR-CS)model.Eventually,the simulation analysis and comparative experiments manifest that the proposed data encryption scheme possesses strong immunity against various security attack models and satisfactory compression performance. 展开更多
关键词 cellular neural network MEMRISTOR hardware circuit compressive sensing privacy data protection
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Design and mechanical properties analysis of a cellular Waterbomb origami structure
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作者 Yongtao Bai Zhaoyu Wang Yu Shi 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第3期193-202,共10页
Cellular structures are commonly used to design energy-absorbing structures,and origami structures are becominga prevalent method of cellular structure design.This paper proposes a foldable cellular structure based on... Cellular structures are commonly used to design energy-absorbing structures,and origami structures are becominga prevalent method of cellular structure design.This paper proposes a foldable cellular structure based on theWaterbomb origami pattern.The geometrical configuration of this structure is described.Quasi-static compressiontests of the origami tube cell of this cellular structure are conducted,and load-displacement relationship curvesare obtained.Numerical simulations are carried out to analyze the effects of aspect ratio,folding angle,thicknessand number of layers of origami tubes on initial peak force and specific energy absorption(SEA).Calculationformulas for initial peak force and SEA are obtained by the multiple linear regression method.The degree ofinfluence of each parameter on the mechanical properties of the single-layer tube cell is compared.The resultsshow that the cellular structure exhibits negative stiffness and periodic load-bearing capacity,as well as foldingangle has the most significant effect on the load-bearing and energy-absorbing capacity.By adjusting the designparameters,the stiffness,load-bearing capacity and energy absorption capacity of this cellular structure can beadjusted,which shows the programmable mechanical properties of this cellular structure.The foldability andthe smooth periodic load-bearing capacity give the structure potential for application as an energy-absorbing structure. 展开更多
关键词 cellular structure Waterbomb origami Mechanical metamaterial Numerical simulation Energy absorption
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Modeling and Performance Analysis of UAV-Aided Millimeter Wave Cellular Networks with Stochastic Geometry
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作者 Li Junruo Wang Yuanjie +2 位作者 Cui Qimei Hou Yanzhao Tao Xiaofeng 《China Communications》 SCIE CSCD 2024年第6期146-162,共17页
UAV-aided cellular networks,millimeter wave(mm-wave) communications and multi-antenna techniques are viewed as promising components of the solution for beyond-5G(B5G) and even 6G communications.By leveraging the power... UAV-aided cellular networks,millimeter wave(mm-wave) communications and multi-antenna techniques are viewed as promising components of the solution for beyond-5G(B5G) and even 6G communications.By leveraging the power of stochastic geometry,this paper aims at providing an effective framework for modeling and analyzing a UAV-aided heterogeneous cellular network,where the terrestrial base stations(TBSs) and the UAV base stations(UBSs) coexist,and the UBSs are provided with mm-wave and multi-antenna techniques.By modeling the TBSs as a PPP and the UBSs as a Matern hard-core point process of type Ⅱ(MPH-Ⅱ),approximated but accurate analytical results for the average rate of the typical user of both tiers are derived through an approximation method based on the mean interference-to-signal ratio(MISR) gain.The influence of some relevant parameters is discussed in detail,and some insights into the network deployment and optimization are revealed.Numerical results show that some trade-offs are worthy of being considered,such as the antenna array size,the altitude of the UAVs and the power control factor of the UBSs. 展开更多
关键词 average rate DOWNLINK millimeter wave point process theory SIR stochastic geometry UAVaided cellular networks
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Unveiling the cellular microstructure-property relations in martensitic stainless steel via laser powder bed fusion
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作者 Lingzhi Wu Cong Zhang +7 位作者 Dil Faraz Khan Ruijie Zhang Yongwei Wang Xue Jiang Haiqing Yin Xuanhui Qu Geng Liu Jie Su 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第11期2476-2487,共12页
Laser powder bed fusion(LPBF)is a widely recognized additive manufacturing technology that can fabricate complex components rapidly through layer-by-layer formation.However,there is a paucity of research on the effect... Laser powder bed fusion(LPBF)is a widely recognized additive manufacturing technology that can fabricate complex components rapidly through layer-by-layer formation.However,there is a paucity of research on the effect of laser scanning speed on the cellular microstructure and mechanical properties of martensitic stainless steel.This study systematically investigated the influence of laser scanning speed on the cellular microstructure and mechanical properties of a developed Fe11Cr8Ni5Co3Mo martensitic stainless steel produced by LPBF.The results show that increasing the laser scanning speed from 400 to 1000 mm/s does not lead to a noticeable change in the phase fraction,but it reduces the average size of the cellular microstructure from 0.60 to 0.35μm.The scanning speeds of 400 and 1000 mm/s both had adverse effects on performances of sample,resulting in inadequate fusion and keyhole defects respectively.The optimal scanning speed for fabricating samples was determined to be 800 mm/s,which obtained the highest room temperature tensile strength and elongation,with the ultimate tensile strength measured at(1088.3±2.0)MPa and the elongation of(16.76±0.10)%.Furthermore,the mechanism of the evolution of surface morphology,defects,and energy input were clarified,and the relationship between cellular microstructure size and mechanical properties was also established. 展开更多
关键词 laser powder bed fusion martensitic stainless steel cellular microstructure mechanical properties strengthening mechanism
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Current and future research directions in cellular metabolism of colorectal cancer:A bibliometric analysis
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作者 Bo-Wen Jiang Xiu-Hua Zhang +2 位作者 Rui Ma Wen-Yu Luan Yan-Dong Miao 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第8期3732-3737,共6页
The primary aim of this study was to analyze the evolving trends and key focal points in research on cellular metabolism of colorectal cancer(CRC).Relevant publications on cellular metabolism in CRC were sourced from ... The primary aim of this study was to analyze the evolving trends and key focal points in research on cellular metabolism of colorectal cancer(CRC).Relevant publications on cellular metabolism in CRC were sourced from the Science Citation Index Expanded within the Web of Science Core Collection database.Bibliometric analysis and visualization were conducted using VOSviewer(version 1.6.18)software and CiteSpace 6.1.R6(64-bit)Basic.A comprehensive compilation of 4722 English-language publications,covering the period from January 1,1991 to December 31,2022,was carefully identified and included in the analysis.Among the authors,“Ogino,Shuji”contributed the most publications in this field,while“Giovannucci,E”garnered the highest number of citations.The journal“Cancer Research”ranked first in both publication volume and citations.Institutionally,“Shanghai Jiao Tong University”emerged as the top contributor in terms of published articles,while“Harvard University”led in citation impact.In country-based analysis,the United States held the top position in both publication output and citations,closely followed by China.The increasing recognition of the significance of cellular metabolism in CRC underscores its potential for novel therapeutic approaches aimed at improving CRC management and prognosis. 展开更多
关键词 cellular metabolism Colorectal cancer Bibliometric analysis Metabolic reprogramming cellular metabolism
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Resource Allocation in Multi-User Cellular Networks:A Transformer-Based Deep Reinforcement Learning Approach
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作者 Zhao Di Zheng Zhong +2 位作者 Qin Pengfei Qin Hao Song Bin 《China Communications》 SCIE CSCD 2024年第5期77-96,共20页
To meet the communication services with diverse requirements,dynamic resource allocation has shown increasing importance.In this paper,we consider the multi-slot and multi-user resource allocation(MSMU-RA)in a downlin... To meet the communication services with diverse requirements,dynamic resource allocation has shown increasing importance.In this paper,we consider the multi-slot and multi-user resource allocation(MSMU-RA)in a downlink cellular scenario with the aim of maximizing system spectral efficiency while guaranteeing user fairness.We first model the MSMURA problem as a dual-sequence decision-making process,and then solve it by a novel Transformerbased deep reinforcement learning(TDRL)approach.Specifically,the proposed TDRL approach can be achieved based on two aspects:1)To adapt to the dynamic wireless environment,the proximal policy optimization(PPO)algorithm is used to optimize the multi-slot RA strategy.2)To avoid co-channel interference,the Transformer-based PPO algorithm is presented to obtain the optimal multi-user RA scheme by exploring the mapping between user sequence and resource sequence.Experimental results show that:i)the proposed approach outperforms both the traditional and DRL methods in spectral efficiency and user fairness,ii)the proposed algorithm is superior to DRL approaches in terms of convergence speed and generalization performance. 展开更多
关键词 dynamic resource allocation multi-user cellular network spectrum efficiency user fairness
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Advances in micropillar arrays in cellular biomechanics detectionand tissue engineering
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作者 XUELING HE LINLU JIN +3 位作者 YIXUE QIN JIAN ZHONG ZHI OUYANG YE ZENG 《BIOCELL》 SCIE 2024年第11期1521-1529,共9页
Cellular biomechanical features contributed to the occurrence and development of various physiological andpathological phenomena. Micropillar arrays have emerged as an important tool for both the assessment andmanipul... Cellular biomechanical features contributed to the occurrence and development of various physiological andpathological phenomena. Micropillar arrays have emerged as an important tool for both the assessment andmanipulation of cellular biomechanical characteristics. This comprehensive review provides an in-depthunderstanding of the fabrication methodologies of micropillar arrays and their applications in deciphering and finetuning cellular biomechanical properties and the innovative experimental platforms including organ-on-a-chip andorganoids-on-a-chip. This review provides novel insights into the potential of micropillar technology, poised toupdate the landscape of stem cell research and tissue engineering. 展开更多
关键词 Micropillar cellular biomechanics Stem cell LAB-ON-A-CHIP Organoid-on-a-chip
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Dynamics of Land Use/Land Cover Considering Ecosystem Services for a Dense-Population Watershed Based on a Hybrid Dual-Subject Agent and Cellular Automaton Modeling Approach
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作者 Yutong Li Yanpeng Cai +3 位作者 Qiang Fu Xiaodong Zhang Hang Wan Zhifeng Yang 《Engineering》 SCIE EI CAS CSCD 2024年第6期182-195,共14页
Land use/land cover represents the interactive and comprehensive influences between human activities and natural conditions,leading to potential conflicts among natural and human-related issues as well as among stakeh... Land use/land cover represents the interactive and comprehensive influences between human activities and natural conditions,leading to potential conflicts among natural and human-related issues as well as among stakeholders.This study introduced economic standards for farmers.A hybrid approach(CA-ABM)of cellular automaton(CA)and an agent-based model(ABM)was developed to effectively deal with social and land-use synergic issues to examine human–environment interactions and projections of land-use conversions for a humid basin in south China.Natural attributes and socioeconomic data were used to analyze land use/land cover and its drivers of change.The major modules of the CA-ABM are initialization,migration,assets,land suitability,and land-use change decisions.Empirical estimates of the factors influencing the urban land-use conversion probability were captured using parameters based on a spatial logistic regression(SLR)model.Simultaneously,multicriteria evaluation(MCE)and Markov models were introduced to obtain empirical estimates of the factors affecting the probability of ecological land conversion.An agent-based CA-SLR-MCE-Markov(ABCSMM)land-use conversion model was proposed to explore the impacts of policies on land-use conversion.This model can reproduce observed land-use patterns and provide links for forest transition and urban expansion to land-use decisions and ecosystem services.The results demonstrated land-use simulations under multi-policy scenarios,revealing the usefulness of the model for normative research on land-use management. 展开更多
关键词 Land use/land cover Human-environment interactions Agent-based model cellular automaton
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Full-Scale Isogeometric Topology Optimization of Cellular Structures Based on Kirchhoff-Love Shells
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作者 Mingzhe Huang Mi Xiao +3 位作者 Liang Gao Mian Zhou Wei Sha Jinhao Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期2479-2505,共27页
Cellular thin-shell structures are widely applied in ultralightweight designs due to their high bearing capacity and strength-to-weight ratio.In this paper,a full-scale isogeometric topology optimization(ITO)method ba... Cellular thin-shell structures are widely applied in ultralightweight designs due to their high bearing capacity and strength-to-weight ratio.In this paper,a full-scale isogeometric topology optimization(ITO)method based on Kirchhoff-Love shells for designing cellular tshin-shell structures with excellent damage tolerance ability is proposed.This method utilizes high-order continuous nonuniform rational B-splines(NURBS)as basis functions for Kirchhoff-Love shell elements.The geometric and analysis models of thin shells are unified by isogeometric analysis(IGA)to avoid geometric approximation error and improve computational accuracy.The topological configurations of thin-shell structures are described by constructing the effective density field on the controlmesh.Local volume constraints are imposed in the proximity of each control point to obtain bone-like cellular structures.To facilitate numerical implementation,the p-norm function is used to aggregate local volume constraints into an equivalent global constraint.Several numerical examples are provided to demonstrate the effectiveness of the proposed method.After simulation and comparative analysis,the results indicate that the cellular thin-shell structures optimized by the proposed method exhibit great load-carrying behavior and high damage robustness. 展开更多
关键词 cellular thin-shell structures isogeometric analysis full-scale topology optimization Kirchhoff–Love shells
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Cellular strategies to induce immune tolerance after liver transplantation:Clinical perspectives
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作者 Ai-Wei Zhou Jing Jin Yuan Liu 《World Journal of Gastroenterology》 SCIE CAS 2024年第13期1791-1800,共10页
Liver transplantation(LT)has become the most efficient treatment for pediatric and adult end-stage liver disease and the survival time after transplantation is becoming longer due to the development of surgical techni... Liver transplantation(LT)has become the most efficient treatment for pediatric and adult end-stage liver disease and the survival time after transplantation is becoming longer due to the development of surgical techniques and perioperative management.However,long-term side-effects of immunosuppressants,like infection,metabolic disorders and malignant tumor are gaining more attention.Immune tolerance is the status in which LT recipients no longer need to take any immunosuppressants,but the liver function and intrahepatic histology maintain normal.The approaches to achieve immune tolerance after transplantation include spontaneous,operational and induced tolerance.The first two means require no specific intervention but withdrawing immunosuppressant gradually during follow-up.No clinical factors or biomarkers so far could accurately predict who are suitable for immunosuppressant withdraw after transplantation.With the understanding to the underlying mechanisms of immune tolerance,many strategies have been developed to induce tolerance in LT recipients.Cellular strategy is one of the most promising methods for immune tolerance induction,including chimerism induced by hematopoietic stem cells and adoptive transfer of regulatory immune cells.The safety and efficacy of various cell products have been evaluated by prospective preclinical and clinical trials,while obstacles still exist before translating into clinical practice.Here,we will summarize the latest perspectives and concerns on the clinical application of cellular strategies in LT recipients. 展开更多
关键词 cellular therapy Induced tolerance Liver transplantation Regulatory T cells Regulatory dendritic cells
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