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Journal of Advanced Ceramics 2022年第4期11卷 589-602页

作者： Dongbo HONG Zengbin YIN fuzhou guo Juntang YUAN School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China Collaborative Innovation Center of High-End Equipment Manufacturing Technology Nanjing University of Science and TechnologyMinistry of Industry and Information TechnologyNanjing 210094China

Duplexα/β-SiAlON ceramic cutting inserts(30α:70β)were synthesized by microwave sintering.The effects of solid solution parameters(m,n,z),synthesis temperature,and amount of excess Y_(2)O_(3) synthesis additive on phase assemblage,microstructure,mechanical properties,and cutting performance were systematically investigated.It was found that increasing m value could improve the formation ofαphase while high z value over 1.0 resulted in the dissolution ofαphase intoβphase and intergranular phase.Increasing the amount of excess Y_(2)O_(3) could promote densification and elongatedβgrain growth;however,the excess Y_(2)O_(3) amount above 4 wt%resulted in substantial crystallization of M'SS phase,thus declining the mechanical properties and wear resistance.The microwave-synthesizedα/β-SiAlON cutting insert with modified parameters(m=1.7,n=1.0,z=0.7,and 3 wt%excess Y_(2)O_(3))was obtained with optimal comprehensive properties,whose tool life was found to increase by approximately 75%in high-speed milling of Inconel 718 superalloy compared to the commercialα/β-SiAlON cutting insert.

关键词： α/β-SiAlON microwave ceramic cutting insert solid solution parameter Y_(2)O_(3)synthesis additive

Spark plasma sintering ofα/β-SiAlON ceramic end mill rods:Electro-thermal simulation,microstructure,mechanical properties,and machining performance

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Journal of Advanced Ceramics 2023年第9期12卷 1777-1792页

作者： fuzhou guo Zengbin Yin Xuelin Li Juntang Yuan School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China Collaborative Innovation Center of High-End Equipment Manufacturing Technology(Nanjing University of Science and Technology) Ministry of Industry and Information TechnologyNanjing 210094China Nanjing Totem Tool Co. Ltd.Nanjing 211215China

Spark plasma sintering(SPS)is a highly efficient method for the preparation ofα/β-SiAlON ceramics.However,the rapid preparation of large-scaleα/β-SiAlON ceramic components with reliable mechanical properties is difficult via SPS due to their near-insulating properties.In this study,high-performanceα/β-SiAlON ceramic end mill rods with large aspect ratios were successfully prepared via SPS.Two different types of sintering processes(namely vertical-round-rod(VRR)and horizontal-square-rod(HSR)processes)were developed,and their effects on the phase composition,microstructure,mechanical properties,and machining performance of theα/β-SiAlON ceramic end mill rods were studied.The electric and temperature field distributions during sintering were studied through an electro–thermal simulation.The simulated and experimental temperature distributions are in good agreement.In contrast to VRR samples,HSR samples with a small axial size show a uniform temperature distribution and satisfactory microstructures within a certain range of dimensions as well as the expected phase composition;furthermore,elongatedβ-SiAlON grains are preferentially oriented in the direction perpendicular to the sintering pressure direction.As a result,the HSR samples exhibit better mechanical properties and machining performance than the VRR samples.

关键词： α/β-SiAlON ceramics spark plasma sintering(SPS) electro-thermal simulation microstructure mechanical properties orientation

Python程序设计课程中的计算思维教学分析

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电子技术（上海） 2024年第1期53卷 284-285页

作者：郭福洲黄冈职业技术学院电子信息学院湖北438002

阐述Python程序设计课程中的计算机思维特点,探讨基于计算思维的Python程序设计课程教学策略,包括创设情境、利用任务驱动法教学和探究新的教学知识、利用课堂练习巩固学习内容。

关键词：计算思维 Python程序设计课程教学

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集成电路测试管理系统的设计与实现

集成电路应用 2024年第1期41卷 60-61页

作者：郭福洲黄冈职业技术学院电子信息学院湖北438002

阐述在集成电路生产中的测试管理系统设计,该系统能够实现对测试数据的存储和管理,支持数据分析和测试报告的生成,提供测试参数配置和测试流程管理功能。

关键词：集成电路测试管理系统测试流程管理

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职业院校顶岗实习管理存在的问题与对策

黄冈职业技术学院学报 2022年第1期24卷 24-26页

作者：郭福洲黄冈职业技术学院电子信息学院湖北黄冈438002

职业院校实习是学生步入社会的前期接轨实战,也是学生人生成长的重大转变。本文就现代中高职院校学生在顶岗实习过程中暴露出的社会性事件与舆情关注点,对关联对象:学生、学校、实习企事业单位、教师和家长心态与立场进行剖析,并从主观... 详细信息

职业院校实习是学生步入社会的前期接轨实战,也是学生人生成长的重大转变。本文就现代中高职院校学生在顶岗实习过程中暴露出的社会性事件与舆情关注点,对关联对象:学生、学校、实习企事业单位、教师和家长心态与立场进行剖析,并从主观和客观方面提出一些有针对性的建议:学生应在主观意识上锤炼个人吃苦耐劳意志力,拓展人际交往方面的情商;学校应将教育部实习要求文件精神宣传引导落实前移、做细做强;企事业方做好学生入职期间心理疏导、技能培养,以情留人;实习指导教师多走进学生工作生活场所,走进学生心灵,帮助他们强健三观;家长应对子女多关心多激励,教导他们独立自强。多方合力同心,共同促进学生身心健康成长。

关键词：产业转型顶岗实习技能素养学生管理职业院校

Impact of Alcian blue and periodic acid Schiff expression on the prognosis of gastric signet ring cell carcinoma

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 687-698页

作者： Juan Lin Zhu-Feng Chen guo-Dong guo Xin Chen Shengli Clinical Medical College Fujian Medical UniversityFuzhou 350001Fujian ProvinceChina Department of Pathology Fujian Provincial HospitalFuzhou 350001Fujian ProvinceChina Department of Internal Medicine Fujian Provincial HospitalFuzhou 350001Fujian ProvinceChina

BACKGROUND The Alcian blue(AB)and periodic acid Schiff(PAS)stains are representative mucus markers in gastric signet ring cell carcinoma(SRCC).They are low-cost special staining methods used to detect acidic mucus and neutral mucus,respectively.However,the clinical importance of the special combined AB and PAS stain is unclear.AIM To investigate AB expression,PAS expression and the AB-to-PAS(A/P)ratio in gastric SRCC patients and to assess patient prognosis.METHODS Paraffin-embedded sections from 83 patients with gastric SRCC were stained with AB and PAS,and signet ring cell positivity was assessed quantitatively.Immuno-histochemical staining for Ki67,protein 53(P53)and human epidermal growth factor receptor 2(HER2)was performed simultaneously.The cancer-specific survival(CSS)rate was estimated via Kaplan-Meier analysis.Cox proportional hazards models were used for univariate and multivariate survival analyses.RESULTS Kaplan-Meier survival analysis revealed that the 3-year CSS rate was significantly greater in the high-PAS-expression subgroup than in the low-PAS-expression subgroup(P0.5 group(P=0.042).Univariate Cox regression analysis revealed that the factors affecting prognosis included tumor diameter,lymph node metastasis,vessel carcinoma embolus,tumor stage,the A/P ratio and the expression of Ki67,P53 and the PAS.Cox multivariate regression analysis confirmed that low PAS expression[hazard ratio(HR)=3.809,95%confidence interval(CI):1.563-9.283,P=0.003]and large tumor diameter(HR=2.761,95%CI:1.086-7.020,P=0.033)were independent risk factors for poor prognosis.CONCLUSION A/P>0.5 is potentially a risk factor for prognosis,and low PAS expression is an independent risk factor in the prognosis of gastric SRCC.PAS expression and the A/P ratio could help in predicting the clinical prognosis of patients with SRCC.

关键词： Alcian blue Periodic acid-Schiff Prognosis Gastric Signet ring cell carcinoma

MULTIPLE POSITIVE SOLUTIONS TO BOUNDARY VALUE PROBLEMS FOR SECOND-ORDER SYSTEM OF QUASILINEAR DIFFERENCE EQUATIONS

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Annals of Differential Equations 2008年第1期24卷 105-111页

作者： Zhang Jiehua (College of Sunshine,fuzhou University,fuzhou 350015) guo Yanping (College of Sciences,Hebei University of Science and Technology,Shijiazhuang 050018)

This paper presents sufficient conditions for the existence of positive solutions to some second-order system of difference equations subject to some boundary conditions. We show that it has at least three positive so... 详细信息

关键词： boundary value problem multiple positive solution fixed point theorem

Recent Advances in Mechanistic Understanding of Metal-Free Carbon Thermocatalysis and Electrocatalysis with Model Molecules

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Nano-Micro Letters 2024年第7期16卷 74-97页

作者： Wei guo Linhui Yu Ling Tang Yan Wan Yangming Lin CAS Key Laboratory of Design and Assembly of Functional Nanostructures Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002People’s Republic of China Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Institute of Rare Earth MaterialsHaixi InstituteChinese Academy of SciencesXiamen 361021People’s Republic of China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002People’s Republic of China Institute of Urban Environment Chinese Academy of SciencesXiamen 361021People’s Republic of China

Metal-free carbon,as the most representative heterogeneous metal-free catalysts,have received considerable interests in electro-and thermo-catalytic reac-tions due to their impressive performance and sustainability.Over the past decade,well-designed carbon catalysts with tunable structures and heteroatom groups coupled with various characterization techniques have proposed numerous reaction mechanisms.However,active sites,key intermediate species,precise structure-activity relationships and dynamic evolution processes of carbon catalysts are still rife with controversies due to the monotony and limitation of used experimental methods.In this Review,we sum-marize the extensive efforts on model catalysts since the 2000s,particularly in the past decade,to overcome the influences of material and structure limitations in metal-free carbon catalysis.Using both nanomolecule model and bulk model,the real contribution of each alien species,defect and edge configuration to a series of fundamentally important reactions,such as thermocatalytic reactions,electrocatalytic reactions,were systematically studied.Combined with in situ techniques,isotope labeling and size control,the detailed reaction mechanisms,the precise 2D structure-activity relationships and the rate-determining steps were revealed at a molecular level.Furthermore,the outlook of model carbon catalysis has also been proposed in this work.

关键词： Metal-free carbon catalysts Model catalyst Electrocatalysis Active site Reaction mechanisms

Alterations in nasal microbiota of patients with amyotrophic lateral sclerosis

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Chinese Medical Journal 2024年第2期137卷 162-171页

作者： Kaixiong Liu Qifu guo Ying Ding Li Luo Jianchai Huang Qijie Zhang Department of Respiratory and Critical Care Medicine The First Affiliated HospitalFujian Medical UniversityFuzhouFujian 350005China Department of Respiratory and Critical Care MedicineNational Regional Medical CenterBinhai Campus of The First Affiliated HospitalFujian Medical UniversityFuzhouFujian 350212China Department of Neurology Fujian Institute of NeurologyThe First Affiliated HospitalFujian Medical UniversityFuzhouFujian 350005China Department of NeurologyNational Regional Medical CenterBinhai Campus of The First Affiliated HospitalFujian Medical UniversityFuzhouFujian 350212China

Background:Links between alterations in gut microbiota composition and amyotrophic lateral sclerosis(ALS)have previously been reported.This study aimed to examine the microbiota in the nasal cavity of ALS.Methods:Sixty-six ALS patients and 40 healthy caregivers who live in close proximity with patients were enrolled.High throughput metagenomic sequencing of the 16S ribosomal deoxyribonucleic acid(rDNA)gene V3-V4 region of nasal microbiota was used to characterize the alpha and beta diversity and relative abundance of bacterial taxa,predict function,and conduct correlation analysis between specific taxa and clinical features.Results:The nasal microbiome of ALS patients showed lower alpha diversity than that of corresponding healthy family members.Genera Gaiella,Sphingomonas,Polaribacter_1,Lachnospiraceae_NK4A136_group,Klebsiella,and Alistipes were differentially enriched in ALS patients compared to controls.Nasal microbiota composition in ALS patients significantly differed from that in healthy subjects(unweighted UniFrac P=0.001),while Linear discriminant analysis Effect Size(LEfSe)analysis indicated that Bacteroidetes and Firmicutes dominated healthy nasal communities at the phylum level,whereas Actinobacteria was the predominant phylum and Thermoleophilia was the predominant class in ALS patients.Genus Faecalibacterium and Alistipes were positively correlated with ALS functional rating scale revised(ALSFRS-R;r_(s)=0.349,P=0.020 and r_(s)=0.393,P=0.008),while Prevotella-9 and Bacteroides operational taxonomic units(OTUs)were positively associated with lung function(FVC)in ALS patients(r_(s)=0.304,P=0.045,and r_(s)=0.300,P=0.048,respectively).Prevotella-1 was positively correlated with white blood cell counts(WBC,r_(s)=0.347,P=0.021),neutrophil percentage(Neu%,r_(s)=0.428,P=0.004),and neutrophil-to-lymphocyte ratio(NLR,r_(s)=0.411,P=0.006),but negatively correlated with lymphocyte percentage(Lym%,r_(s)=-0.408,P=0.006).In contrast,Streptococcus was negatively associated with Neu%(r_(s)=-0.445,P=0.003)and NLR(r_(s)

关键词： Amyotrophic lateral sclerosis Nasal microbiota Dysbiosis Inflammation

Emodin suppresses alkali burn-induced corneal inflammation and neovascularization by the vascular endothelial growth factor receptor 2 signaling pathway

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Journal of Traditional Chinese Medicine 2024年第2期44卷 268-276页

作者： ZHENG Xueying guo Liang LAI Siyi LI Fengyue LIANG Mingli LIU Wanting MENG Chun LIU Guanghui Department of Bioengineering College of Biological Science and BiotechnologyFuzhou UniversityFuzhou 350104China Eye Institute of Integrated Chinese and Western Medicine Fujian University of Traditional Chinese MedicineFuzhou 350004China Department of Ophthalmology Affiliated People's Hospital(Fujian Provincial People's Hospital)Fujian University of Traditional Chinese MedicineFuzhou 350004China

OBJECTIVE:To investigate the effects of emodin on alkali burn-induced corneal inflammation and neovascularization.METHODS:The ability of emodin to target vascular endothelial growth factor receptor 2(VEGFR2)was predicted by molecular docking.The effects of emodin on the invasion,migration,and proliferation of human umbilical vein endothelial cells(HUVEC)were determined by cell counting kit-8,Transwell,and tube formation assays.Analysis of apoptosis was performed by flow cytometry.CD31 levels were examined by immunofluorescence.The abundance and phosphorylation state of VEGFR2,protein kinase B(Akt),signal transducer and activator of transcription 3(STAT3),and P38 were examined by immunoblot analysis.Corneal alkali burn was performed on 40 mice.Animals were divided randomly into two groups,and the alkali-burned eyes were then treated with drops of either 10μM emodin or phosphate buffered saline(PBS)four times a day.Slitlamp microscopy was used to evaluate inflammation and corneal neovascularization(CNV)in all eyes on Days 0,7,10,and 14.The mice were killed humanely 14 d after the alkali burn,and their corneas were removed and preserved at-80℃ until histological study or protein extraction.RESULTS:Molecular docking confirmed that emodin was able to target VEGFR2.The findings revealed that emodin decreased the invasion,migration,angiogenesis,and proliferation of HUVEC in a dose-dependent manner.In mice,emodin suppressed corneal inflammatory cell infiltration and inhibited the development of corneal neovascularization induced by alkali burn.Compared to those of the PBS-treated group,lower VEGFR2 expression and CD31 levels were found in the emodintreated group.Emodin dramatically decreased the expression of VEGFR2,p-VEGFR2,p-Akt,p-STAT3,and p-P38 in VEGF-treated HUVEC.CONCLUSION:This study provides a new avenue for evaluating the molecular mechanisms underlying corneal inflammation and neovascularization.Emodin might be a promising new therapeutic option for corneal alkali burns.

关键词： alkali burn emodin corneal inflammation corneal neovascularisation vascular endothelial growth factor receptor-2 signal transduction