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离心泵叶片斜开槽抑制空化的研究

中国农村水利水电 2024年第10期 119-126页

作者：赵伟国李兴国聂雄杰刘莹兰州理工大学能源与动力工程学院甘肃兰州730050 普仑斯(福建)泵业有限公司福建松溪353500

为了抑制低比转数离心泵的空化,提出改变叶片开槽轴向角度的方法,并设计了3种叶片斜开槽方案。通过数值模拟的方法,对比离心泵试验结果,分析叶片斜开槽对离心泵空化抑制的效果。模拟结果表明:轴向角度为5°的叶片斜开槽对低比转速离心... 详细信息

为了抑制低比转数离心泵的空化,提出改变叶片开槽轴向角度的方法,并设计了3种叶片斜开槽方案。通过数值模拟的方法,对比离心泵试验结果,分析叶片斜开槽对离心泵空化抑制的效果。模拟结果表明:轴向角度为5°的叶片斜开槽对低比转速离心泵的空化抑制效果最明显,断裂扬程提高了0.281 m;叶片斜开槽抑制了离心泵叶轮流场内空泡的发展,在空化严重阶段空泡体积最多减小了67.25%;叶片斜开槽优化了叶轮流场结构,缩小了叶轮进口低压区,降低了叶轮流道内的湍动能。

关键词：离心泵数值模拟轴向角度斜开槽空化抑制

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高职院校大学生党史学习现状调查及分析

延安职业技术学院学报 2024年第2期38卷 15-21页

作者：李兴国李佳怡尤娜延安职业技术学院陕西延安716000 天津外国语大学滨海外事学院天津300450

将百年党史融入高职思政课堂是提升学生历史素养坚定四个自信的有效措施。通过对高职院校大学生党史学习现状调查,发现学生历史知识欠缺、学习内容单调、形式单一:教师理念陈旧、教学方法单一等是导致思政课堂育人效果不佳的原因。开设... 详细信息

将百年党史融入高职思政课堂是提升学生历史素养坚定四个自信的有效措施。通过对高职院校大学生党史学习现状调查,发现学生历史知识欠缺、学习内容单调、形式单一:教师理念陈旧、教学方法单一等是导致思政课堂育人效果不佳的原因。开设党史课程、利用现代技术、创新教学方式、强化师资培训、改革教学评价机制、在全校范围营造党史学习氛围等策略是提高学生学习党史兴趣、提升思政育人效果的应有之策。

关键词：高职大学生党史学习现状对策探究

宜昌市2017—2022年出生儿童过敏性疾病流行病学特征及多病分析

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现代预防医学 2024年第7期51卷 1175-1180+1205页

作者：孙明伟刘钦王琦琦李国星张艳丽孙谨芳中国疾病预防控制中心流行病学办公室北京大学医学部宜昌市疾病预防控制中心

目的基于宜昌市健康大数据平台，分析宜昌市2017—2022年期间出生的儿童在医疗机构就诊的过敏性疾病特征，明确宜昌市儿童过敏性疾病的多病分布。方法对宜昌市健康大数据云平台中2017—2022年城区综合医疗机构门诊就诊为过敏性疾病的... 详细信息

目的基于宜昌市健康大数据平台，分析宜昌市2017—2022年期间出生的儿童在医疗机构就诊的过敏性疾病特征，明确宜昌市儿童过敏性疾病的多病分布。方法对宜昌市健康大数据云平台中2017—2022年城区综合医疗机构门诊就诊为过敏性疾病的出生儿童患者记录进行统计分析。结果男性儿童就诊68 707人次多于女性儿童的53 292人次，2017年以来就诊人次不断增加，0～1岁医院就诊人次最多，为46 190人次(37.86%)，其中二月龄就诊人次最多，为3 331人次(13.74%)。特应性皮炎/湿疹与过敏性鼻炎的就诊人次较高，分别为46 156和14 388人次。特应性皮炎的发病年龄较早，首次就诊年龄为0.42岁,男性的发病年龄要早于女性，特应性皮炎/湿疹与过敏性鼻炎是最常见的多病。结论对于患有特应性皮炎/湿疹和（或）过敏性鼻炎的儿童，重点关注其伴随疾病的发生，进一步阻断过敏进程，促进疾病早期发现、预防及治疗。

关键词：过敏性疾病儿童多病

Role of CD80 in stimulating T lymphocyte activation

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World Journal of Gastroenterology 2006年第6期12卷 880-884页

作者： De-Chun li xing-guo Zhu Yong Zhang Jian-Xin Fu Departmentof General Surgery the First Affiliated Hospital of Soochow UniversitySuzhou 215006 Jiangsu Province China

AIM： To observe biological characteristics of hepatocarcinoma cells before and after CD80 transfection and to compare the effect of CD80-transfected hepatocarcinoma cells on T lymphocyte activation. METHODS： Retro virus vector carrying CD80 gene was transfected into HepG2 cells to establish CD80transfected hepatocarcinoma cells （HepG2/hCD80）. Flow cytometry （FCM） was performed to detect CD80 expression in the transfected cells. RT-PCR was used to evaluate CD80 expression at mRNA level. In the presence of anti-CD3 mAb, the proliferation of T lymphocyte was observed by M＇n＇. Meanwhile, the expression of activated molecule marker CD25 was analyzed through FCM. RESULTS： A stable cell line HepG2/hCD80 expressing the human CD80 was established. Growth curve showed that the molecule CD80 could obviously decrease the growth of tumor cells. HepG2/hCD80 was evidenced to have a potency to enhance T cell proliferation and upregulate CD25 expression. CONCLUSION： CD80 transfection can lower malignant phenotype of hepatocarcinoma cells. CD80 transfection has a down-regulatory effect to activated T cells in vitro.

关键词： Hepatocarcinoma cells CD80 Transfection T lymphocyte activation

Fullerenes and derivatives as electrocatalysts: Promises and challenges

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Green Energy & Environment 2024年第1期9卷 7-27页

作者： Kun guo Ning li lipiao Bao xing Lu State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China

Carbon-based metal-free nanomaterials are promising alternatives to precious metals as electrocatalysts of key energy storage and conversion *** paramount signiﬁcance are the establishment of design principles by understanding the catalytic mechanisms and identifying the active *** from sp2-conjugated graphene and carbon nanotube,fullerene possesses unique characteristics that are growingly being discovered and exploited by the electrocatalysis *** instance,the well-deﬁned atomic and molecular structures,the good electron afﬁnity to tune the electronic structures of other substances,the intermolecular self-assembly into superlattices,and the on-demand chemical modiﬁcation have endowed fullerene with incomparable advantages as electrocatalysts that are otherwise not applicable to other carbon *** increasing studies are being reported on this intriguing topic,it is necessary to provide a state-of-the-art overview of the recent *** review takes such an initiative by summarizing the promises and challenges in the electrocatalytic applications of fullerene and its *** content is structured according to the composition and structure of fullerene,including intact fullerene(e.g.,fullerene composite and superlattices)and fullerene derivatives(e.g.,doped,endohedral,and disintegrated fullerene).The synthesis,characterization,catalytic mechanisms,and deﬁciencies of these fullerene-based materials are explicitly *** conclude it by sharing our perspectives on the key aspects that future efforts shall consider.

关键词： Fullerene Fullerene derivative Metal-free catalyst Structural defect Electrocatalyst

CdTe quantum dots as fluorescence sensor for the determination of vitamin B6 in aqueous solution

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Chinese Chemical Letters 2008年第7期19卷 855-859页

作者： Jie Fang Sun Cui ling Ren li Hong liu xing guo Chen Department of Chemistry Lanzhou University Lanzhou 730000 China

A novel, rapid and simple CdTe quantum dots （QDs） based technology platform was established for selective and sensitive determination of vitamin B6 in aqueous solution. It can perform accurate and reproducible quant... 详细信息

关键词： CdTe QDs Determination Fluorescence sensor Vitamin B6

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青海鸟类新纪录——钳嘴鹳

湿地科学与管理 2024年第1期20卷 92-93页

作者：王建民李国兴张凤展天津市滨海新区疆北湿地保护中心天津300450

2023年7月下旬于青海省玉树州下拉秀镇(96.567560°E,32.584536°N,海拔3857.04 m)记录到1只大型鹳类水鸟,经鉴定,为钳嘴鹳(Anastomus oscitans),系青海省鸟类新记录。

关键词：钳嘴鹳鸟类新记录青海玉树

Genome-wide identification and function analysis of the sucrose phosphate synthase MdSPS gene family in apple

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Journal of Integrative Agriculture 2023年第7期22卷 2080-2093页

作者： ZHANG li-hua ZHU ling-cheng XU Yu LÜLong li xing-guo li Wen-hui liU Wan-da MA Feng-wang li Ming-jun HAN De-guo The Key Laboratory of Biology and Genetic Improvement of Horticultural Crops(Northeast Region) Ministry of Agriculture and Rural Affairs/National-Local Joint Engineering Research Center for Development and Utilization of Small Fruits in Cold RegionsCollege of Horticulture&Landscape ArchitectureNortheast Agricultural UniversityHarbin 150030P.R.China State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple College of HorticultureNorthwest A&F UniversityYangling 712100P.R.China Horticulture Branch Heilongjiang Academy of Agricultural SciencesHarbin 150040P.R.China

Sucrose phosphate synthase(SPS)is a rate-limiting enzyme that works in conjunction with sucrose-6-phosphate phosphatase(SPP)for sucrose synthesis,and it plays an essential role in energy provisioning during growth and development in plants as well as improving fruit ***,studies on the systematic analysis and evolutionary pattern of the SPS gene family in apple are still *** the present study,a total of seven MdSPS and four MdSPP genes were identified from the Malus domestica genome GDDH13 *** gene structures and their promoter cis-elements,protein conserved motifs,subcellular localizations,physiological functions and biochemical properties were analyzed.A chromosomal location and gene-duplication analysis demonstrated that whole-genome duplication(WGD)and segmental duplication played vital roles in MdSPS gene family *** Ka/Ks ratio of pairwise MdSPS genes indicated that the members of this family have undergone strong purifying selection during ***,three SPS gene subfamilies were classified based on phylogenetic relationships,and old gene duplications and significantly divergent evolutionary rates were observed among the SPS gene *** addition,a major gene related to sucrose accumulation(MdSPSA2.3)was identified according to the highly consistent trends in the changes of its expression in four apple varieties(‘Golden Delicious’,‘Fuji’,‘Qinguan’and‘Honeycrisp’)and the correlation between gene expression and soluble sugar content during fruit ***,the virus-induced silencing of MdSPSA2.3 confirmed its function in sucrose accumulation in apple *** present study lays a theoretical foundation for better clarifying the biological functions of the MdSPS genes during apple fruit development.

关键词： apple sucrose phosphate synthase evolutionary pattern expression profile sugar accumulation

Construction of an oral recombinant DNA vaccine from H pylori neutrophil activating protein and its immunogenicity

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World Journal of Gastroenterology 2006年第43期12卷 7042-7046页

作者： Bo Sun Zhao-Shen li Zhen-xing Tu guo-Ming Xu Yi-Qi Du Department of Gastroenterology Changhai Hospital SecondMilitary Medical University Shanghai 200433 China

AIM： To construct a live attenuated Salmonella typhimurium （S. typhimurium） strain harboring the H pylori neutrophil activating protein （HP-NAP） gene as an oral recombinant DNA vaccine, and to evaluate its immunogenicity. METHODS： By genetic engineering methods, the genomic DNA of Hpylori was extracted as a template. The total length of the HP-NAP gene was amplified by polymerase chain reaction （PCR） and cloned into pBT vector for sequencing and BLAST analysis, then subcloned into a eukaryotic expression vector pIRES followed by PCR identification and restriction enzyme digestion. The identified recombinant plasmid pIRES-NAP was transfected into COS-7 cells for target fusion protein expression, and its antigenicity was detected by Western blotting. Then the recombinant plasmid was transformed into a live attenuated S. typhimurium strain SL7207 as an oral vaccine strain, and its immunogenicity was evaluated with animal experiments. RESULTS： A 435 bp product was cloned using high homology with HP-NAP gene in GenBank （more than 98%）. With identification by PCR and restriction enzyme digestion, a recomoinant eukaryotic expression plasmid pIRES-NAP containing the HP-NAP gene of H pylori was successfully constructed. The expressed target protein had a specific reaction with Hpyloril whole cell antibody and showed a single strip result detected by Western blotting. Oral immunization of mice with recombinant DNA vaccine strain SL7207 （pIRES-NAP） also induced a specific immune response. CONCLUSION： The successful construction of HP-NAP oral DNA vaccine with good immunogenicity may help to further investigate its immunoprotection effects and develop vaccine against Hpylori infection.

关键词： H pylori Neutrophil activating protein DNAvaccine