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人工林米老排木材解剖性质及其变异性研究

北京林业大学学报 2007年第3期29卷 142-148页

作者：梁善庆罗建举中国林业科学研究院木材工业研究所广西大学林学院

为了解人工林米老排木材解剖性质,并探求其木材材质变异规律的内在机制,为建立米老排“培育—材性—加工利用”一体化的模式提供必要的理论依据,该文借助电子显微镜和计算机显微图像分析系统,从微观的角度,应用定量解剖学方法,对米老排... 详细信息

为了解人工林米老排木材解剖性质,并探求其木材材质变异规律的内在机制,为建立米老排“培育—材性—加工利用”一体化的模式提供必要的理论依据,该文借助电子显微镜和计算机显微图像分析系统,从微观的角度,应用定量解剖学方法,对米老排木材解剖性质及其沿径向的变异规律进行了系统的测定和分析.研究结果表明:①米老排纤维长度、宽度、双壁厚、长宽比、壁腔比、腔径比平均值分别为2 014.2μm、26.19μm、11.07μm、78.68、0.79、0.57;由髓心向外除腔径比呈递减趋势外其余纤维形态指标呈递增趋势.②导管分子长度、宽度、双壁厚、长宽比、壁腔比、腔径比平均值分别为1 666.0μm5、3.83μm、5.44μm、31.85、0.12、0.90;由髓心向外除双壁厚和壁腔比呈递减趋势外其余导管分子形态指标呈递增趋势.③纤维比量、导管比量、木射线比量和薄壁组织比量平均值分别为54.8%、16.5%、27.6%1、.1%;由髓心向外木纤维比量呈增加趋势,导管分子比量呈递减趋势,木射线比量和薄壁组织比量变异规律不明显.④微纤丝角平均值为8.4°,由髓心向外呈递减趋势.⑤幼龄材与成熟材的界限为第7年.

关键词：人工林米老排解剖性质变异规律

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基于共面特征点的单目视觉位姿测量误差分析

光子学报 2014年第5期43卷 144-150页

作者：霍炬崔家山王伟兴哈尔滨工业大学电气工程系哈尔滨150001 哈尔滨工业大学控制与仿真中心哈尔滨150001

为了克服单目视觉测量中景深信息缺失的问题,运用改进的两段式迭代算法,对刚体位姿测量解算模型进行了优化.给出了特征标靶最优化布局,理论分析了标靶尺寸大小、标靶基线长度及特征圆点大小和解算准确度的关系.实验结果表明,优化的特征... 详细信息

为了克服单目视觉测量中景深信息缺失的问题,运用改进的两段式迭代算法,对刚体位姿测量解算模型进行了优化.给出了特征标靶最优化布局,理论分析了标靶尺寸大小、标靶基线长度及特征圆点大小和解算准确度的关系.实验结果表明,优化的特征标靶布局、较大的特征标靶基线长度及较小的特征圆点靶标能够提高测量解算准确度.该研究对提高实际测量系统解算准确度具有一定的理论指导意义.

关键词：位姿测量单目视觉景深估计共面特征点坐标统一化

煤巷围岩变形破坏机制模型试验研究及工程应用

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采矿与安全工程学报 2017年第3期34卷 464-471页

作者：孔祥松单仁亮剧通达中国矿业大学(北京)力学与建筑工程学院北京100083

为研究煤巷围岩变形破坏机制,将汾西矿区煤巷作为原型进行物理相似模型试验研究。阐述了试验设计,改进了平面模型实验台,通过配比试验确定了煤岩层的相似材料,建立煤巷物理相似模型,研究煤巷在无支护状态下围岩应力分布规律、位移和变... 详细信息

为研究煤巷围岩变形破坏机制,将汾西矿区煤巷作为原型进行物理相似模型试验研究。阐述了试验设计,改进了平面模型实验台,通过配比试验确定了煤岩层的相似材料,建立煤巷物理相似模型,研究煤巷在无支护状态下围岩应力分布规律、位移和变形破坏特征,分析煤巷变形破坏机制以论证煤巷强帮强角支护技术,并进行了工程实践应用。研究结果表明:煤巷破坏源于帮部和角部,帮部、角部与顶板相互加剧破坏,导致煤巷失稳。相对位移是反映围岩破坏程度的关键指标,帮部相对位移远大于顶板。煤巷帮部破坏最严重,属于局部垮落破坏,垮落深高比为0.29;顶板破坏属于整体下沉破坏,在角部2条主裂纹作用下有冒落趋势;角部属于裂纹破坏形式,贯通后会跟随帮部或顶板垮落。可见,控制煤巷帮部和角部变形破坏,提高其支护强度,是保证煤巷围岩稳定性的关键,论证了煤巷强帮强角支护技术。工程监测表明,强帮强角支护技术具有良好的适用性。

关键词：煤巷围岩变形破坏机制帮部模型试验

Probiotic Bio-Three induces Th1 and anti-inflammatory effects in PBMC and dendritic cells

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World Journal of Gastroenterology 2010年第28期16卷 3529-3540页

作者： Man-Chin Hua Tzou-Yien Lin Chien-Chang Chen Ming-Wei Lai Man-shan Kong Hung-ju Chang Department of Pediatrics Chang Gung Memorial Hospital Keelung 204 Taiwan China Graduate Institute of Clinical Medical Sciences College of Medicine Chang Gung University Taoyuan 333 Division of Infectious Disease Division of Gastroenterology Department of Pediatrics Chang Gung Memorial HospitalTaoyuan 333TaiwanChina

AIM:To investigate the immune response of peripheral blood mononuclear cells(PBMCs)and dendritic cells (DCs)that were stimulated by probiotic preparations. METHODS:PBMCs were isolated,cultured,and stimulated with Bio-Three(a mixture of Bacillus mesentericus, Clostridium butyricum and Enterococcus faecalis;105, 10 6 and 10 7 CFU/mL for 24 h).Cytokine production of (1)circulating PBMCs;(2)PBMCs stimulated by probiotic preparation;(3)monocyte-derived DCs;and(4)DC andT cell co-culture was determined by enzyme-linked immunosorbent *** analysis of circulating PBMCs was also investigated by flow *** was obtained from individuals who consumed Bio-Three (10 9 CFU/d ***,*** and ***) for 2 wk,or those who did not take probiotics orally. RESULTS:In culture supernatants,interferon-γ(IFN-γ) and interleukin(IL)-10 production increased,but IL-4 and tumor necrosis factor-α(TNF-α)production by PBMCs decreased after 1 and 2 wk of probiotic *** cytometry was also performed on day 14 and detected enhanced expression of CD11b,HLA-DR, CD4,CD45RA,CD25,CD44 and CD69 in response to ***,IL-10 and IL-12 were upregulated in supernatants of monocyte-derived DCs,and IFN-γand IL-10 were enhanced in supernatants of CD4 + T cells co-cultured with DCs. CONCLUSION:Bio-Three appeared to stimulate the Th1 immune response,downregulate pro-inflammatory cytokines(TNF-α)and upregulate anti-inflammatory cytokine(IL-10).Probiotics could be effective in activation of PBMCs and DCs.

关键词： Probiotics Bio-Three Peripheral blood mono- nuclear cells Dendritic cells

Effect of Hepatitis C Virus Core Protein on Interferon-Induced Antiviral Genes Expression and Its Mechanisms

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中国病毒学 2007年第5期22卷 374-379页

作者： Yan-zi CHANG Yan-chang LEI Wen WU shan-shan CHEN Han-ju HUANG Dong-liang YANG Meng-ji LU Department of Pathogen Biology Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China Division of Clinical Immunology Tongji Hospital Huazhong University of Science and Technology Wuhan 430030 China.

Emerging data indicated that HCV subverts the antiviral activity of interferon(IFN);however,whether HCV core protein contributes to the process remains *** the present study,we examined the effect of HCV core protein on interferon-induced antiviral gene expression and whether the effect is involved in the activation and negative regulation of the Jak/STAT signaling *** results showed that,following treatment with IFN-α,the transcription of PKR,MxA and 2'-5'OAS were down-regulated in HepG2 cells expressing the core *** the presence of HCV core protein,ISRE-dependent luciferase activity also *** study indicated that the core protein could inhibit the tyrosine phosphorylation of STAT1,whereas the level of STAT1 expression was ***,SOCS3,the negative regulator of the Jak/STAT pathway,was induced by HCV core *** results suggests that HCV core protein may interfere with the expression of some interferon-induced antiviral genes by inhibiting STAT1 phosphorylation and induction of SOCS3.

关键词：丙型肝炎病毒核心蛋白质 α-干扰素抗病毒基因表达作用机理

Depression of biofilm formation and antibiotic resistance by sarA disruption in Staphylococcus epidermidis

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World Journal of Gastroenterology 2006年第25期12卷 4009-4013页

作者： ju-Hong Tao Chang-Sheng Fan shan-E Gao Hai-Jiao Wang Guo-Xin Liang Qing Zhang Department of Microbiology School of Life Sciences Fudan University Shanghai 200433 China

AIM： To study the effects of disruption of sarA gene on biofilm formation and antibiotic resistance of Staphylococcus epidermidis （ S. epiderrnidis）. METHODS： In order to disrupt sarA gene, the double- crossover homologous recombination was applied in S. epiderrnidis RP62A, and tetracycline resistance gene （tet） was used as the selective marker which was amplified by PCR from the pBR322 and inserted into the locus between sarA upstream and downstream, resulting in pBT2ΔsarA. By electroporation, the plasmid pBT2ΔsarA was transformed into S. epiderrnidis. Gene transcription was detected by real-time reverse transcription-PCR （RT-PCR）. Determination of biofilm was performed in 96-well flat-bottomed culture plates, and antibiotic resistance was analyzed with test tube culture by spectrophotometry at 570 nm respectively. RESULTS： A sarA disrupted strain named S. epiderrnidis RP62AΔsarA was constructed, which was completely defective in biofilm formation, while the sarA complement strain RP62AΔsarA （pHPS9sarA） restored the biofilm formation phenotype. Additionally, the knockout of sarA resulted in decreased erythromycin and kanamycin resistance of S. epiderrnidis RP62A. Compared to the original strain, S. epiderrnidis RP62AΔsarA had an increase of the sensitivity to erythromycin at 200-400 μg/mL and kanamycin at 200-800 μg/mL respectively. CONCLUSION： The knockout of sarA can result in the defect in biofilm formation and the decreased erythromycin and kanamycin resistance in S. epiderrnidis RP62A.

关键词： sarA Biofilm Antibiotic resistance Staphylococcus epidermidis

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远程网络教学的理论与实践

河北学刊 2008年第4期28卷 196-198页

作者：窦聚山邢台广播电视大学河北邢台054000

在计算机网络环境下的远程教育中,师生在相对分离的条件下进行知识的传授和获取,除了给学生提供一个很好的印刷教材之外,课程网络教学资源是保证学生学习的重要条件。本文介绍了课程网络教学资源应包括的媒体内容以及如何科学地把多种... 详细信息

在计算机网络环境下的远程教育中,师生在相对分离的条件下进行知识的传授和获取,除了给学生提供一个很好的印刷教材之外,课程网络教学资源是保证学生学习的重要条件。本文介绍了课程网络教学资源应包括的媒体内容以及如何科学地把多种媒体教学资源有机地结合,为学生提供一个轻松方便的学习环境,使学习效果达到最佳。

关键词：远程教育教学资源课程教学多元媒体课程资源建设

Is burnout a mediating factor between sharps injury and workrelated factors or musculoskeletal pain?

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World Journal of Clinical Cases 2021年第25期9卷 7391-7404页

作者： Yong-Hsin Chen Chin-Feng Tsai Chih-jung yeh Gwo-Ping Jong Department of Public Health Chung Shan Medical UniversityTaichung 40201Taiwan Department of Occupational Safety and Health Chung Shan Medical University HospitalTaichung 40201Taiwan Division of Cardiology Department of Internal MedicineChung Shan Medical University HospitalTaichung 40201Taiwan School of Medicine Chung Shan Medical UniversityTaichung 40201Taiwan Department of Internal Medicine Chung Shan Medical University Hospital and Chung Shan Medical UniversityTaichung 40201Taiwan

BACKGROUND Burnout,musculoskeletal pain,and sharps injuries(SIs)affect medical *** To establish a model between SIs,burnout,and the risk factors to assess the extent to which burnout affects *** This questionnaire was used for an observational and cross-sectional study,which was based on members at a hospital affiliated with a medical university in Taichung,Taiwan,in *** valid responses constituted 68.5%(1734 of 2531).The items were drawn from the Nordic Musculoskeletal Questionnaire and Copenhagen burnout inventory and concerned work experience,occupational category,presence of chronic diseases,sleep duration,overtime work,and work *** analysis,chi-square test,Fisher exact test,Multiple linear,logistic regression and Sobel test were *** present analyses were performed using SAS Enterprise Guide 6.1 software(SAS Institute Inc.,Cary,NC,United States),and significance was set at P Q3) and highwork-related burnout (> Q3) mediated the relationship between SIs and frequentlower limb pain. Similarly, frequent lower limb pain mediated the relationship ofSIs with high personal and high work-related burnout. High personal and highwork-related burnout mediated the relationships of SIs with overtime work andirregular shift work. The mediating model provides strong evidence of anassociation between mental health and *** was determined to contribute to SIs occurrence;specifically, it mediatedthe relationships of SIs with frequent musculoskeletal pain, overtime work, andirregular shift work.

关键词： Personal burnout Work-related burnout Sharps injuries Musculoskeletal pain Mediating factor Overtime work

船舶动力装置复杂形状零部件CAE智能仿真研究

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舰船科学技术 2022年第18期44卷 130-133页

作者：单文举吉林大学珠海学院机械工程学院广东珠海519041

针对船舶动力装置复杂形状零件模型应用性差的缺陷,研究船舶动力装置复杂形状零件CAE智能仿真方法。利用CAD软件设计船舶动力装置复杂形状零件的几何模型,依据CAD模型数据构建零件的CAE分析模型。CAE软件通过前处理部分定义零件模型的... 详细信息

针对船舶动力装置复杂形状零件模型应用性差的缺陷,研究船舶动力装置复杂形状零件CAE智能仿真方法。利用CAD软件设计船舶动力装置复杂形状零件的几何模型,依据CAD模型数据构建零件的CAE分析模型。CAE软件通过前处理部分定义零件模型的单元属性与材料属性,利用信息元理论划分完成属性定义模型网格,对完成划分后的模型网格实施加载与求解,利用后处理过程分析求解数据,分析结果传送至船舶动力装置模型库内,通过图表方式输出仿真分析结果。仿真测试结果表明,该方法有效构建船舶柴油机曲轴的CAE模型,获取施加10 kN扭转变形力后,柴油机曲轴的受力结果,所构建模型应用于柴油机实际运行时,仿真压力输出结果与实际压力吻合度高。

关键词：船舶动力装置复杂形状零部件 CAE 智能仿真信息元理论单元属性