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Finite Element Simulation Analysis of a Novel 3D-FRSPA for Crawling Locomotion
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作者 Bingzhu Wang Xiangrui Ye 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1401-1425,共25页
A novel three-dimensional-fiber reinforced soft pneumatic actuator(3D-FRSPA)inspired by crab claw and human hand structure that can bend and deform independently in each segment is proposed.It has an omni-directional ... A novel three-dimensional-fiber reinforced soft pneumatic actuator(3D-FRSPA)inspired by crab claw and human hand structure that can bend and deform independently in each segment is proposed.It has an omni-directional bending configuration,and the fibers twined symmetrically on both sides to improve the bending performance of FRSPA.In this paper,the static and kinematic analysis of 3D-FRSPA are carried out in detail.The effects of fiber,pneumatic chamber and segment length,and circular air chamber radius of 3D-FRSPA on the mechanical performance of the actuator are discussed,respectively.The soft mobile robot composed of 3D-FRSPA has the ability to crawl.Finally,the crawling processes of the soft mobile robot on different road conditions are studied,respectively,and the motion mechanism of the mobile actuator is shown.The numerical results show that the soft mobile robots have a good comprehensive performance,which verifies the correctness of the proposedmodel.This work shows that the proposed structures have great potential in complex road conditions,unknown space detection and other operations. 展开更多
关键词 3D-FRSPA bionic structure theoretical modeling crawling application obstacle avoidance analysis numerical investigation
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Cookie Baking Process Optimization and Quality Analysis Based on Food 3D Printing
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作者 Liu Chenghai Li Jingyi +2 位作者 Wu Chunsheng Zhao Xinglong Zheng Xianzhe 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第1期61-73,共13页
In order to obtain better quality cookies, food 3D printing technology was employed to prepare cookies. The texture, color, deformation, moisture content, and temperature of the cookie as evaluation indicators, the in... In order to obtain better quality cookies, food 3D printing technology was employed to prepare cookies. The texture, color, deformation, moisture content, and temperature of the cookie as evaluation indicators, the influences of baking process parameters, such as baking time, surface heating temperature and bottom heating temperature, on the quality of the cookie were studied to optimize the baking process parameters. The results showed that the baking process parameters had obvious effects on the texture, color, deformation, moisture content, and temperature of the cookie. All of the roasting surface heating temperature, bottom heating temperature and baking time had positive influences on the hardness, crunchiness, crispiness, and the total color difference(ΔE) of the cookie. When the heating temperatures of the surfac and bottom increased, the diameter and thickness deformation rate of the cookie increased. However,with the extension of baking time, the diameter and thickness deformation rate of the cookie first increased and then decreased. With the surface heating temperature of 180 ℃, the bottom heating temperature of 150 ℃, and baking time of 15 min, the cookie was crisp and moderate with moderate deformation and uniform color. There was no burnt phenomenon with the desired quality. Research results provided a theoretical basis for cookie manufactory based on food 3D printing technology. 展开更多
关键词 food 3D printing baking process COOKIE quality analysis optimization of process parameter
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AHermitian C^(2) Differential Reproducing Kernel Interpolation Meshless Method for the 3D Microstructure-Dependent Static Flexural Analysis of Simply Supported and Functionally Graded Microplates
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作者 Chih-Ping Wu Ruei-Syuan Chang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期917-949,共33页
This work develops a Hermitian C^(2) differential reproducing kernel interpolation meshless(DRKIM)method within the consistent couple stress theory(CCST)framework to study the three-dimensional(3D)microstructuredepend... This work develops a Hermitian C^(2) differential reproducing kernel interpolation meshless(DRKIM)method within the consistent couple stress theory(CCST)framework to study the three-dimensional(3D)microstructuredependent static flexural behavior of a functionally graded(FG)microplate subjected to mechanical loads and placed under full simple supports.In the formulation,we select the transverse stress and displacement components and their first-and second-order derivatives as primary variables.Then,we set up the differential reproducing conditions(DRCs)to obtain the shape functions of the Hermitian C^(2) differential reproducing kernel(DRK)interpolant’s derivatives without using direct differentiation.The interpolant’s shape function is combined with a primitive function that possesses Kronecker delta properties and an enrichment function that constituents DRCs.As a result,the primary variables and their first-and second-order derivatives satisfy the nodal interpolation properties.Subsequently,incorporating ourHermitianC^(2)DRKinterpolant intothe strong formof the3DCCST,we develop a DRKIM method to analyze the FG microplate’s 3D microstructure-dependent static flexural behavior.The Hermitian C^(2) DRKIM method is confirmed to be accurate and fast in its convergence rate by comparing the solutions it produces with the relevant 3D solutions available in the literature.Finally,the impact of essential factors on the transverse stresses,in-plane stresses,displacements,and couple stresses that are induced in the loaded microplate is examined.These factors include the length-to-thickness ratio,the material length-scale parameter,and the inhomogeneity index,which appear to be significant. 展开更多
关键词 Consistent/modified couple stress theory differential reproducing kernel methods microplates point collocation methods static flexural 3D microstructure-dependent analysis
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A Bioinformatics Analysis of FAM3A to Identify its Potential Role as a Biomarker in Liver Hepatocellular Cancer
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作者 Syed Hussain Raza 《Proceedings of Anticancer Research》 2024年第4期87-97,共11页
Liver hepatocellular cancer(LIHC)is positioned as the third cancer with the highest mortalities worldwide,and high mortalities are associated with late diagnosis and recurrence.This study advances bioinformatics analy... Liver hepatocellular cancer(LIHC)is positioned as the third cancer with the highest mortalities worldwide,and high mortalities are associated with late diagnosis and recurrence.This study advances bioinformatics analysis of FAM3A expression in LIHC to evaluate its potential as a prognostic,diagnostic and therapeutic biomarker.Bioinformatics tools such as UALCAN,GEPIA2,KM plotter,TIMER2 and cBioPortal are employed to conduct analysis.Initially,the expression analysis revealed up-regulation of FAM3A in LIHC based on various variables.Further,the study observed that FAM3A methylation regulates expression as variation in methylation level of FAM3A was assessed in LIHC.Moreover,this over-expression of FAM3A results in poor overall survival(OS)in LIHC patients.All of these proposed that FAM3A has a role in the progression and development of LIHC.While examined association of FAM3A expression and infiltration level of CD8+T cells in LIHC patients using TIMER2 revealed that FAM3A has a positive correlation with purity in LIHC that highlights the molecular landscape.Analysis of genetic alteration revealed minute role of FAM3A in LIHC still provides valuable insight.Overall,our findings reveal that FAM3A has potential as diagnostic,therapeutic and prognostic biomarkers in LIHC. 展开更多
关键词 Liver hepatocellular cancer(LIHC) FAM3A expression Bioinformatics analysis BIOMARKER
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DI-3-n-butylphthalide exerts neuroprotective effects by modulating hypoxia-inducible factor 1-alpha ubiquitination to attenuate oxidative stress-induced apoptosis 被引量:8
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作者 Shuai Li Jingyuan Zhao +4 位作者 Yan Xi Jiaqi Ren Yanna Zhu Yan Lu Deshi Dong 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第11期2424-2428,共5页
DI-3-n-butylphthalide is used to treat mild and moderate acute ischemic stroke.However,the precise underlying mechanism requires further investigation.In this study,we investigated the molecular mechanism of DI-3-n-bu... DI-3-n-butylphthalide is used to treat mild and moderate acute ischemic stroke.However,the precise underlying mechanism requires further investigation.In this study,we investigated the molecular mechanism of DI-3-n-butylphthalide action by various means.We used hydrogen peroxide to induce injury to PC12cells and RAW264.7 cells to mimic neuronal oxidative stress injury in stroke in vitro and examined the effects of DI-3-n-butylphthalide.We found that DI-3-nbutylphthalide pretreatment markedly inhibited the reduction in viability and reactive oxygen species production in PC12 cells caused by hydrogen peroxide and inhibited cell apoptosis.Furthermore,DI-3-n-butylphthalide pretreatment inhibited the expression of the pro-apoptotic genes Bax and Bnip3.DI-3-nbutylphthalide also promoted ubiquitination and degradation of hypoxia inducible factor 1α,the key transcription factor that regulates Bax and Bnip3 genes.These findings suggest that DI-3-n-butylphthalide exhibits a neuroprotective effect on stroke by promoting hypoxia inducible factor-1α ubiquitination and degradation and inhibiting cell apoptosis. 展开更多
关键词 blood-brain barrier Dl-3-n-butylphthalide hypoxia inducible factor MITOCHONDRIA NEUROPROTECTION oxidative stress reactive oxygen species stroke transcription factor UBIQUITINATION
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DL-3-n-butylphthalide alleviates motor disturbance by suppressing ferroptosis in a rat model of Parkinson’s disease 被引量:3
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作者 Chun-Bo Hu Hui Jiang +5 位作者 Yin Yang Guo-Hua Wang Qiu-Hong Ji Zhong-Zheng Jia Li-Hua Shen Qian-Qian Luo 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第1期194-199,共6页
DL-3-n-butylphthalide(NBP)-a compound isolated from Apium graveolens seeds-is protective against brain ischemia via various mechanisms in humans and has been approved for treatment of acute ischemic stroke.NBP has sho... DL-3-n-butylphthalide(NBP)-a compound isolated from Apium graveolens seeds-is protective against brain ischemia via various mechanisms in humans and has been approved for treatment of acute ischemic stroke.NBP has shown recent potential as a treatment for Parkinson’s disease.However,the underlying mechanism of action of NBP remains poorly understood.In this study,we established a rat model of Parkinson’s disease by intraperitoneal injection of rotenone for 28 successive days,followed by intragastric injection of NBP for 14-28 days.We found that NBP greatly alleviated rotenone-induced motor disturbance in the rat model of Parkinson’s disease,inhibited loss of dopaminergic neurons and aggregation ofα-synuclein,and reduced iron deposition in the substantia nigra and iron content in serum.These changes were achieved by alterations in the expression of the iron metabolism-related proteins transferrin receptor,ferritin light chain,and transferrin 1.NBP also inhibited oxidative stress in the substantia nigra and protected mitochondria in the rat model of Parkinson’s disease.Our findings suggest that NBP alleviates motor disturbance by inhibition of iron deposition,oxidative stress,and ferroptosis in the substantia nigra. 展开更多
关键词 cystine/glutamate antiporter solute carrier family 7 member 11 DL-3-n-butylphthalide ferritin light chain ferroportin 1 ferroptosis glutathione peroxidase 4 oxidative stress iron ROTENONE transferrin receptor
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A novel box-counting method for quantitative fractal analysis of threedimensional pore characteristics in sandstone
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作者 Huiqing Liu Heping Xie +2 位作者 Fei Wu Cunbao Li Renbo Gao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第4期479-489,共11页
Fractal theory offers a powerful tool for the precise description and quantification of the complex pore structures in reservoir rocks,crucial for understanding the storage and migration characteristics of media withi... Fractal theory offers a powerful tool for the precise description and quantification of the complex pore structures in reservoir rocks,crucial for understanding the storage and migration characteristics of media within these rocks.Faced with the challenge of calculating the three-dimensional fractal dimensions of rock porosity,this study proposes an innovative computational process that directly calculates the three-dimensional fractal dimensions from a geometric perspective.By employing a composite denoising approach that integrates Fourier transform(FT)and wavelet transform(WT),coupled with multimodal pore extraction techniques such as threshold segmentation,top-hat transformation,and membrane enhancement,we successfully crafted accurate digital rock models.The improved box-counting method was then applied to analyze the voxel data of these digital rocks,accurately calculating the fractal dimensions of the rock pore distribution.Further numerical simulations of permeability experiments were conducted to explore the physical correlations between the rock pore fractal dimensions,porosity,and absolute permeability.The results reveal that rocks with higher fractal dimensions exhibit more complex pore connectivity pathways and a wider,more uneven pore distribution,suggesting that the ideal rock samples should possess lower fractal dimensions and higher effective porosity rates to achieve optimal fluid transmission properties.The methodology and conclusions of this study provide new tools and insights for the quantitative analysis of complex pores in rocks and contribute to the exploration of the fractal transport properties of media within rocks. 展开更多
关键词 3D fractal analysis Fractal dimension Rock pore structure Box-counting method Permeability simulation Computational geosciences
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Biomechanical analysis of an absorbable material for treating fractures of the inferior orbital wall
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作者 Jin-Hai Yu Ze-Xi Sang +4 位作者 Huang Zhang Qi-Hua Xu Qin Huang Hong-Fei Liao Yao-Hua Wang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第7期1331-1336,共6页
AIM:To investigate the biomechanical properties and practical application of absorbable materials in orbital fracture repair.METHODS:The three-dimensional(3D)model of orbital blowout fractures was reconstructed using ... AIM:To investigate the biomechanical properties and practical application of absorbable materials in orbital fracture repair.METHODS:The three-dimensional(3D)model of orbital blowout fractures was reconstructed using Mimics21.0 software.The repair guide plate model for inferior orbital wall fracture was designed using 3-matic13.0 and Geomagic wrap 21.0 software.The finite element model of orbital blowout fracture and absorbable repair plate was established using 3-matic13.0 and ANSYS Workbench 21.0 software.The mechanical response of absorbable plates,with thicknesses of 0.6 and 1.2 mm,was modeled after their placement in the orbit.Two patients with inferior orbital wall fractures volunteered to receive single-layer and double-layer absorbable plates combined with 3D printing technology to facilitate surgical treatment of orbital wall fractures.RESULTS:The finite element models of orbital blowout fracture and absorbable plate were successfully established.Finite element analysis(FEA)showed that when the Young’s modulus of the absorbable plate decreases to 3.15 MPa,the repair material with a thickness of 0.6 mm was influenced by the gravitational forces of the orbital contents,resulting in a maximum total deformation of approximately 3.3 mm.Conversely,when the absorbable plate was 1.2 mm thick,the overall maximum total deformation was around 0.4 mm.The half-year follow-up results of the clinical cases confirmed that the absorbable plate with a thickness of 1.2 mm had smaller maximum total deformation and better clinical efficacy.CONCLUSION:The biomechanical analysis observations in this study are largely consistent with the clinical situation.The use of double-layer absorbable plates in conjunction with 3D printing technology is recommended to support surgical treatment of infraorbital wall blowout fractures. 展开更多
关键词 orbital blowout fracture absorbable material finite element analysis 3D printing technology
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Multivariate adaptive regression splines analysis for 3D slope stability in anisotropic and heterogenous clay 被引量:1
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作者 Jim Shiau Van Qui Lai Suraparb Keawsawasvong 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第4期1052-1064,共13页
Little research can be found in relation to the stability of anisotropic and heterogenous soils in three dimensions.In this paper,we propose a study on the three-dimensional(3D)undrained slopes in anisotropic and hete... Little research can be found in relation to the stability of anisotropic and heterogenous soils in three dimensions.In this paper,we propose a study on the three-dimensional(3D)undrained slopes in anisotropic and heterogenous clay using advanced upper and lower bounds finite element limit analysis(FELA).The obtained stability solutions are normalized,and presented by a stability number that is a function of three geometrical ratios and two material ratios,i.e.depth ratio,length ratio,slope angle,shear strength gradient ratio and anisotropic strength ratio.Numerical results are compared with experimental data in the literature,and charts are presented to cover a wide range of design parameters.Using the multivariate adaptive regression splines(MARS)analysis,the respective influence and sensitivity of each design parameter on the stability number and the failure mechanism are investigated.An empirical equation is also developed to effectively estimate the stability number. 展开更多
关键词 3D undrained slope Limit analysis ANISOTROPY HETEROGENEITY
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The Clinical Value of Ultrasound Image Texture Analysis in the Diagnosis of Uterine Adhesions
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作者 Meng Li Chanyu Zhang 《Open Journal of Obstetrics and Gynecology》 2024年第2期312-320,共9页
Purpose: This review examines the diagnostic value of transvaginal 3D ultrasound image texture analysis for the diagnosis of uterine adhesions. Materials and Methods: The total clinical data of 53 patients with uterin... Purpose: This review examines the diagnostic value of transvaginal 3D ultrasound image texture analysis for the diagnosis of uterine adhesions. Materials and Methods: The total clinical data of 53 patients with uterine adhesions diagnosed by hysteroscopy and the imaging data of transvaginal three-dimensional ultrasound from the Second Affiliated Hospital of Chongqing Medical University from June 2022 to August 2023 were retrospectively analysed. Based on hysteroscopic surgical records, patients were divided into two independent groups: normal endometrium and uterine adhesion sites. The samples were divided into a training set and a test set, and the transvaginal 3D ultrasound was used to outline the region of interest (ROI) and extract texture features for normal endometrium and uterine adhesions based on hysteroscopic surgical recordings, the training set data were feature screened and modelled using lasso regression and cross-validation, and the diagnostic efficacy of the model was assessed by applying the subjects’ operating characteristic (ROC) curves. Results: For each group, 290 texture feature parameters were extracted and three higher values were screened out, and the area under the curve of the constructed ultrasonographic scoring model was 0.658 and 0.720 in the training and test sets, respectively. Conclusion Relative clinical value of transvaginal three-dimensional ultrasound image texture analysis for the diagnosis of uterine adhesions. 展开更多
关键词 Transvaginal 3D Ultrasound Intrauterine Adhesion Texture analysis
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Carbon Chain Length Determines Inhibitory Potency of Perfluoroalkyl Sulfonic Acids on Human Placental 3β-Hydroxysteroid Dehydrogenase 1:Screening,Structure-Activity Relationship,and In Silico Analysis
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作者 TANG Lu Ming MAO Bai Ping +4 位作者 ZHANG Bing Ru LI Jing Jing TANG Yun Bing LI Hui Tao GE Ren Shan 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2023年第11期1015-1027,共13页
Objective This study aimed to compare 9 perfluoroalkyl sulfonic acids(PFSA)with carbon chain lengths(C4–C12)to inhibit human placental 3β-hydroxysteroid dehydrogenase 1(3β-HSD1),aromatase,and rat 3β-HSD4 activitie... Objective This study aimed to compare 9 perfluoroalkyl sulfonic acids(PFSA)with carbon chain lengths(C4–C12)to inhibit human placental 3β-hydroxysteroid dehydrogenase 1(3β-HSD1),aromatase,and rat 3β-HSD4 activities.Methods Human and rat placental 3β-HSDs activities were determined by converting pregnenolone to progesterone and progesterone secretion in JEG-3 cells was determined using HPLC/MS–MS,and human aromatase activity was determined by radioimmunoassay.Results PFSA inhibited human 3β-HSD1 structure-dependently in the order:perfluorooctanesulfonic acid(PFOS,half-maximum inhibitory concentration,IC50:9.03±4.83μmol/L)>perfluorodecanesulfonic acid(PFDS,42.52±8.99μmol/L)>perfluoroheptanesulfonic acid(PFHpS,112.6±29.39μmol/L)>perfluorobutanesulfonic acid(PFBS)=perfluoropentanesulfonic acid(PFPS)=perfluorohexanesulfonic acid(PFHxS)=perfluorododecanesulfonic acid(PFDoS)(ineffective at 100μmol/L).6:2FTS(1H,1H,2H,2H-perfluorooctanesulfonic acid)and 8:2FTS(1H,1H,2H,2H-perfluorodecanesulfonic acid)did not inhibit human 3β-HSD1.PFOS and PFHpS are mixed inhibitors,whereas PFDS is a competitive inhibitor.Moreover,1–10μmol/L PFOS and PFDS significantly reduced progesterone biosynthesis in JEG-3 cells.Docking analysis revealed that PFSA binds to the steroid-binding site of human 3β-HSD1 in a carbon chain length-dependent manner.All 100μmol/L PFSA solutions did not affect rat 3β-HSD4 and human placental aromatase activity.Conclusion Carbon chain length determines inhibitory potency of PFSA on human placental 3β-HSD1 in a V-shaped transition at PFOS(C8),with inhibitory potency of PFOS>PFDS>PFHpS>PFBS=PFPS=PFHxS=PFDoS=6:2FTS=8:2FTS. 展开更多
关键词 3β-hydroxysteroid dehydrogenase 1 Docking analysis Perfluorooctanesulfonic acid PROGESTERONE STRUCTURE-ACTIVITYRELATIONSHIP
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The Deformation Analysis of the 3D Alignment Control Network Based on the Multiple Congruence Models
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作者 Xudong ZHANG Wenjun CHEN +5 位作者 Xiaodong ZHANG Yajun ZHENG Bin ZHANG Shaoming WANG Jiandong YUAN Guozhen SUN 《Journal of Geodesy and Geoinformation Science》 CSCD 2023年第2期21-31,共11页
In the construction and maintenance of particle accelerators,all the accelerator elements should be installed in the same coordinate system,only in this way could the devices in the actual world be consistent with the... In the construction and maintenance of particle accelerators,all the accelerator elements should be installed in the same coordinate system,only in this way could the devices in the actual world be consistent with the design drawings.However,with the occurrence of the movements of the reinforced concrete cover plates at short notice or building deformations in the long term,the control points upon the engineering structure will be displaced,and the fitness between the subnetwork and the global control network may be irresponsible.Therefore,it is necessary to evaluate the deformations of the 3D alignment control network.Different from the extant investigations,in this paper,to characterize the deformations of the control network,all of the congruent models between the points measured in different epochs have been identified,and the congruence model with the most control points is considered as the primary or fundamental model,the remaining models are recognized as the additional ones.Furthermore,the discrepancies between the primary S-transformation parameters and the additional S-transformation parameters can reflect the relative movements of the additional congruence models.Both the iterative GCT method and the iterative combinatorial theory are proposed to detect multiple congruence models in the control network.Considering the actual work of the alignment,it is essential to identify the competitive models in the monitoring network,which can provide us a hint that,even the fitness between the subnetwork and the global control network is good,there are still deformations which may be ignored.The numerical experiments show that the suggested approaches can describe the deformation of the 3D alignment control network roundly. 展开更多
关键词 similarity transformation 3D alignment control network deformation analysis hypothesis testing iterative global congruence test iterative combinatorial theory
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A Comparative Analysis of the New -3(-n) - 1 Remer Conjecture and a Proof of the 3n + 1 Collatz Conjecture
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作者 Mike Remer 《Journal of Applied Mathematics and Physics》 2023年第8期2216-2220,共5页
This scientific paper is a comparative analysis of two mathematical conjectures. The newly proposed -3(-n) - 1 Remer conjecture and how it is related to and a proof of the more well known 3n + 1 Collatz conjecture. An... This scientific paper is a comparative analysis of two mathematical conjectures. The newly proposed -3(-n) - 1 Remer conjecture and how it is related to and a proof of the more well known 3n + 1 Collatz conjecture. An overview of both conjectures and their respective iterative processes will be presented. Showcasing their unique properties and behavior to each other. Through a detailed comparison, we highlight the similarities and differences between these two conjectures and discuss their significance in the field of mathematics. And how they prove each other to be true. 展开更多
关键词 -3(-n) - 1 Remer Conjecture 3n + 1 Collatz Conjecture Comparative analysis PROOF Natural Numbers Integer Sequences Factorial Processes Par-tial Differential Equations Bounded Values Collatz Conjecture Collatz Algo-rithm Collatz Operator Collatz Compliance And Mathematical Conjectures
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C_(3)产业链高质量发展研究及建议
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作者 双玥 夏静怡 韩月明 《化学工业》 CAS 2024年第1期1-6,共6页
分析预测了我国丙烯及其衍生物聚丙烯、丙烯腈、丙烯酸、苯酚/丙酮、环氧丙烷、丁辛醇等的市场供需情况;指出了我国C_(3)产业链产能全面过剩的原因;提出了新形势下进入C_(3)产业链的切入点、高质量发展建议。
关键词 丙烯及其衍生物 C_(3)产业链 市场分析预测 高质量发展 建议
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西安地区3~6岁儿童脚型分类及特征规律分析
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作者 罗向东 赵美荣 +2 位作者 张祥发 杨美 强威 《陕西科技大学学报》 北大核心 2024年第4期17-24,共8页
针对当前市场童鞋设计不合理和缺乏儿童脚型理论研究参考问题,本研究首先使用三维足部扫描仪获取到3~6岁的52名男童和71名女童三维脚型数据,进行儿童脚型特点和差异的对比分析;其次,采用相关性分析和主成分分析将26组多维指标降维处理至... 针对当前市场童鞋设计不合理和缺乏儿童脚型理论研究参考问题,本研究首先使用三维足部扫描仪获取到3~6岁的52名男童和71名女童三维脚型数据,进行儿童脚型特点和差异的对比分析;其次,采用相关性分析和主成分分析将26组多维指标降维处理至3个主成分:脚长因子、宽围因子和高度因子;然后,以提取的3个主成分作为分类标准进行H-K聚类分析,将儿童脚型分为3类:细瘦足、适中足、肥壮足,其中左脚细瘦足占比最多,右脚适中足占比最多;最后,将脚长尺寸标准化,发现儿童脚型存在显著的性别及左右脚差异.该研究结论可为童鞋设计和鞋楦三维数字化构建提供理论参考. 展开更多
关键词 3~6岁儿童 脚型特征规律 H-K聚类分析 脚型分类 性别差异
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Analysis of the autophagy gene expression profile of pancreatic cancer based on autophagy-related protein microtubule-associated protein 1A/1B-light chain 3 被引量:14
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作者 Yan-Hui Yang Yu-Xiang Zhang +3 位作者 Yang Gui Jiang-Bo Liu Jun-Jun Sun Hua Fan 《World Journal of Gastroenterology》 SCIE CAS 2019年第17期2086-2098,共13页
BACKGROUND Pancreatic cancer is a highly invasive malignant tumor. Expression levels of the autophagy-related protein microtubule-associated protein 1 A/1 B-light chain 3(LC3) and perineural invasion(PNI) are closely ... BACKGROUND Pancreatic cancer is a highly invasive malignant tumor. Expression levels of the autophagy-related protein microtubule-associated protein 1 A/1 B-light chain 3(LC3) and perineural invasion(PNI) are closely related to its occurrence and development. Our previous results showed that the high expression of LC3 was positively correlated with PNI in the patients with pancreatic cancer. In this study, we further searched for differential genes involved in autophagy of pancreatic cancer by gene expression profiling and analyzed their biological functions in pancreatic cancer, which provides a theoretical basis for elucidating the pathophysiological mechanism of autophagy in pancreatic cancer and PNI.AIM To identify differentially expressed genes involved in pancreatic cancer autophagy and explore the pathogenesis at the molecular level.METHODS Two sets of gene expression profiles of pancreatic cancer/normal tissue(GSE16515 and GSE15471) were collected from the Gene Expression Omnibus.Significance analysis of microarrays algorithm was used to screen differentially expressed genes related to pancreatic cancer. Gene Ontology(GO) analysis and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway analysis were used to analyze the functional enrichment of the differentially expressed genes. Protein interaction data containing only differentially expressed genes was downloaded from String database and screened. Module mining was carried out by Cytoscape software and ClusterOne plug-in. The interaction relationship between the modules was analyzed and the pivot nodes between the functional modules were determined according to the information of the functional modules and the data of reliable protein interaction network.RESULTS Based on the above two data sets of pancreatic tissue total gene expression, 6098 and 12928 differentially expressed genes were obtained by analysis of genes with higher phenotypic correlation. After extracting the intersection of the two differential gene sets, 4870 genes were determined. GO analysis showed that 14 significant functional items including negative regulation of protein ubiquitination were closely related to autophagy. A total of 986 differentially expressed genes were enriched in these functional items. After eliminating the autophagy related genes of human cancer cells which had been defined, 347 differentially expressed genes were obtained. KEGG pathway analysis showed that the pathways hsa04144 and hsa04020 were related to autophagy. In addition,65 clustering modules were screened after the protein interaction network was constructed based on String database, and module 32 contains the LC3 gene,which interacts with multiple autophagy-related genes. Moreover, ubiquitin C acts as a pivot node in functional modules to connect multiple modules related to pancreatic cancer and autophagy.CONCLUSION Three hundred and forty-seven genes associated with autophagy in human pancreatic cancer were concentrated, and a key gene ubiquitin C which is closely related to the occurrence of PNI was determined, suggesting that LC3 may influence the PNI and prognosis of pancreatic cancer through ubiquitin C. 展开更多
关键词 Pancreatic cancer Autophagy-related PROTEIN microtubule-associated PROTEIN 1A/1B-light chain 3 Perineural invasion Gene Ontology analysis Kyoto ENCYCLOPEDIA of Genes and Genomes pathway analysis Ubiquitin C
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INVERSE KINEMATIC AND DYNAMIC ANALYSIS OF A 3-DOF PARALLEL MECHANISM 被引量:23
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作者 LiJianfeng WangJinsong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2003年第1期54-58,共5页
According to the structure character of the passive sub-chain of the 3TPS-TPparallel mechanism, the kinematic constraint equations of the movable platform are established,based on which the closed-form inverse kinemat... According to the structure character of the passive sub-chain of the 3TPS-TPparallel mechanism, the kinematic constraint equations of the movable platform are established,based on which the closed-form inverse kinematics formula of the parallel mechanism are presented.Through parting the spherical joints of the active sub-chains and using the force and momentequilibrium of both the active sub-chains and passive sub-chain, the constraint forces acting on theparted joints are determined. Subsequently, the analytic expressions of the actuator driving forcesare derived by means of the force equilibrium of the upper links of active sub-chains. 展开更多
关键词 3TPS-TP parallel mechanism KINEMATICS DYNAMICS analysis
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3-N-Butylphthalide mitigates high glucose-induced injury to Schwann cells:association with nitrosation and apoptosis 被引量:7
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作者 Dan-Dan Xu Wen-Ting Li +4 位作者 Dan Jiang Huai-Guo Wu Ming-Shan Ren Mei-Qiao Chen Yuan-Bo Wu 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第3期513-518,共6页
A high glucose state readily causes peripheral axon atrophy, demyelination, loss of nerve fiber function, and delayed regeneration. However, few studies have examined whether nitration is also critical for diabetic pe... A high glucose state readily causes peripheral axon atrophy, demyelination, loss of nerve fiber function, and delayed regeneration. However, few studies have examined whether nitration is also critical for diabetic peripheral neuropathy. Therefore, this study investigated the effects of high glucose on proliferation, apoptosis, and 3-nitrotyrosine levels of Schwann cells treated with butylphthalide. In addition, we explored potential protective mechanisms of butylphthalide on peripheral nerves. Schwann cells were cultured in vitro with high glucose then stimulated with the peroxynitrite anion inhibitors uric acid and 3-n-butylphthalide for 48 hours. Cell Counting Kit-8 and flow cytometry were used to investigate the effects of uric acid and 3-n-butylphthalide on proliferation and apoptosis of Schwann cells exposed to a high glucose environment. Effects of uric acid and 3-n-butylphthalide on levels of 3-nitrotyrosine in Schwann cells were detected by enzyme-linked immunosorbent assay. The results indicated that Schwann cells cultured in high glucose showed decreased proliferation, but increased apoptosis and intracellular 3-nitrotyrosine levels. However, intervention with uric acid or 3-n-butylphthalide could increase proliferation of Schwann cells cultured in high glucose, and inhibited apoptosis and intracellular 3-nitrotyrosine levels. According to our data, 3-n-butylphthalide may inhibit cell nitrification and apoptosis, and promote cell proliferation, thereby reducing damage to Schwann cells caused by high glucose. 展开更多
关键词 nerve REGENERATION Schwann cells 3-n-butylphthalide 3-NITROTYROSINE nitration stress uric acid PEROXYNITRITE anions diabetic peripheral neuropathy APOPTOSIS proliferation neural REGENERATION
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L-3-n-butylphthalide protects against vascular dementia via activation of the Akt kinase pathway 被引量:18
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作者 Yaping Huai Yanhong Dong +4 位作者 Jing Xu Nan Meng Chunfeng Song Wenbin Li Peiyuan Lv 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第19期1733-1742,共10页
As a neuroprotective drug for the treatment of ischemic stroke, 3-n-butylphthalide, a celery seed ex- tract, has been approved by the State Food and Drug Administration of China as a clinical therapeutic drug for isch... As a neuroprotective drug for the treatment of ischemic stroke, 3-n-butylphthalide, a celery seed ex- tract, has been approved by the State Food and Drug Administration of China as a clinical therapeutic drug for ischemic stroke patients. L-3-n-butylphthalide possesses significant efficacy in the treatment of acute ischemic stroke. The activated Akt kinase pathway can prevent the death of nerve cells and exhibit neuroprotective effects in the brain after stroke. This study provides the hypothesis that I-3-n- butylphthalide has a certain therapeutic effect on vascular dementia, and its mechanism depends on the activation of the Akt kinase pathway. A vascular dementia mouse model was established by cere- bral repetitive ischemia/reperfusion, and intragastrically administered I-3-n-butylphthalide daily for 28 consecutive days after ischemia/repedusion, or 7 consecutive days before ischemia/reperfusion. The Morris water maze test showed significant impairment of spatial learning and memory at 4 weeks after operation, but intragastric administration of I-3-n-butylphthalide, especially pretreatment with I-3-n- butylphthalide, significantly reversed these changes. Thionine staining and western blot analylsis showed that preventive and therapeutic application of I-3-n-butylphthalide can reduce loss of pyrami- dal neurons in the hippocampal CA1 region and alleviate nerve damage in mice with vascular demen- tia. In addition, phosphorylated Akt expression in hippocampal tissue increased significantly after I-3-n- butylphthalide treatment. Experimental findings demonstrate that I-3-n-butylphthalide has preventive and therapeutic effects on vascular dementia, and its mechanism may be mediated by upregulation of phosphorylated Akt in the hippocampus. 展开更多
关键词 neural regeneration brain injury ISCHEMIA/REPERFUSION Akt phosphorylated Akt Morris water maze cog-nitive function 3-n-butylphthalide hippocampus learning memory DEMENTIA grants-supported paper NEUROREGENERATION
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Hypoxia inducible factor-1alpha mediates protection of DL-3-n-butylphthalide in brain microvascular endothelial cells against oxygen glucose deprivation-induced injury 被引量:7
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作者 Weihong Yang Ling Li +3 位作者 Ruxun Huang Zhong Pei Songjie Liao Jinsheng Zeng 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第12期948-954,共7页
Studies have demonstrated that DL-3-n-butylphthalide can significantly alleviate oxygen glucose deprivation-induced injury of human umbilical vein endothelial cells at least partly associated with its enhancement on o... Studies have demonstrated that DL-3-n-butylphthalide can significantly alleviate oxygen glucose deprivation-induced injury of human umbilical vein endothelial cells at least partly associated with its enhancement on oxygen glucose deprivation-induced hypoxia inducible factor-1α expression.In this study,we hypothesized that DL-3-n-butylphthalide can protect against oxygen glucose deprivation-induced injury of newborn rat brain microvascular endothelial cells by means of upregulating hypoxia inducible factor-1α expression.MTT assay and Hoechst staining results showed that DL-3-n-butylphthalide protected brain microvascular endothelial cells against oxygen glucose deprivation-induced injury in a dose-dependent manner.Western blot and immunofluorescent staining results further confirmed that the protective effect was related to upregulation of hypoxia inducible factor-1α.Real-time RT-PCR reaction results showed that DL-3-n-butylphthalide reduced apoptosis by inhibiting downregulation of pro-apoptotic gene caspase-3 mRNA expression and upregulation of apoptosis-executive protease bcl-2 mRNA expression;however,DL-3-n-butylphthalide had no protective effects on brain microvascular endothelial cells after knockdown of hypoxia inducible factor-1α by small interfering RNA.These findings suggest that DL-3-n-butylphthalide can protect brain microvascular endothelial cells against oxygen glucose deprivation-induced injury by upregulating bcl-2 expression and downregulating caspase-3 expression though hypoxia inducible factor-1α pathway. 展开更多
关键词 DL-3-n-butylphthalide APOPTOSIS brain microvascular endothelial cells hypoxia inducible factor-1α
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