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中医适宜技术对2型糖尿病患者血糖指标水平影响的Mate分析
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作者 李娜 张建波 《中国科技期刊数据库 医药》 2024年第7期0071-0076,共6页
通过Mate分析评价中医适宜技术对糖尿病患者血糖水平的干预效果。方法 人工系统检索PubMed、Co-chraneLibrary、Embase、WebofScience、中国知网(CNKI)、万方数据库(WanfangDatabase)、中国生物医学文献数据库(CBM)、维普中文科技期刊... 通过Mate分析评价中医适宜技术对糖尿病患者血糖水平的干预效果。方法 人工系统检索PubMed、Co-chraneLibrary、Embase、WebofScience、中国知网(CNKI)、万方数据库(WanfangDatabase)、中国生物医学文献数据库(CBM)、维普中文科技期刊数据库(VIP)等有关中医适宜技术对糖尿病患者血糖水平干预的相关实验。检索时间为建库日期至2024年3月,由2名研究者按照文献纳入和排除标准进行文献筛选并整理相关数据资料。本文对纳入的文献采用revman5.4软件进行mate分析。结果 共纳入文献13篇,患者病例数共551例。Meta分析结果显示:中医适宜技术可以有效降低2型糖尿病患者的血糖指标[MD=-0.62,95%CI(-0.71,-0.54),P<0.001]结论 中医适宜技术特别是针灸技术对于降低2型糖尿病患者的血糖指标有显著性效果,但其他中医适宜技术需要相互配合才能到达理想效果水平。 展开更多
关键词 中医适宜技术 2型糖尿病 Mate分析
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Design and verification of portable direct shear tester with application to remolded colluvium geomaterials
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作者 K.J.Shou Y.W.Lin 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE 2012年第4期326-332,共7页
The mechanical properties of colluvium strongly govern the stability of colluvial slopes, and they arc essential for the related analysis and design. Nevertheless, their measurement is not easy on account of heterogen... The mechanical properties of colluvium strongly govern the stability of colluvial slopes, and they arc essential for the related analysis and design. Nevertheless, their measurement is not easy on account of heterogeneity in property and difficulty of sampling. This study attempted to evaluate the shear strength of remolded colluvium by means of a simple direct shear test in the field. A portable direct shear tester was designed to overcome the inconvenience and expensiveness of the conventional large-scale in-situ direct shear test. It can be easily assembled and applied for the silnplc field direct shear test. For calibration, the results of the portable direct shear tester were compared with the results of the laboratory direct shear tester for four different types of soil samples, i.e. standard sand, slate debris, arenaceous shale debris and mixture of gravel and sand. Correlation formulas were established based on the calibration, enabling the portable direct shear tester to measure and estimate the shear strength of remoldcd colluvium in field. This study primarily focuses on the colluvium in Central Taiwan, including the lateritic Dadu Terrace and the arcnaceous shale of Taiping-Wufcng mounts. The portable direct shear tester was applied to sites selected in these areas, and the results were furthcr analyzed and discussed. 展开更多
关键词 direct shear test portable direct shear tester simple field direct shear test colluvial slope
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Line X Tester Analysis of Estimating Heterosis and Combining Ability in F_1 Generation of Sunflower
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作者 Ameer Hussain Jarwar Xiaoyan WANG +2 位作者 Long WANG Qifeng MA Shuli FAN 《Asian Agricultural Research》 2017年第8期70-74,共5页
The present research was conducted in Line X tester analysis for estimating combining ability and heterotic effects,restorers malesterile(CMS) crossed with seven tester lines 3x7 21 F_1 hybrids of sunflower were furth... The present research was conducted in Line X tester analysis for estimating combining ability and heterotic effects,restorers malesterile(CMS) crossed with seven tester lines 3x7 21 F_1 hybrids of sunflower were further used to estimate their general combining ability(GCS),specific combining ability(SCA) and heterosis effects on main traits of sunflower during 2009.For this study,seven lines of sunflower were tested with three testers 7x3 of sunflower to obtain twenty one F_1 genotypes from Line X tester mating design.It was concluded from present study that among the lines,0505 Cms-6,Peshawer-93 Cms-11,Peshawar-93 Cms-12 were the best general combiners to play the vital role in flowering,maturity,plant height,head diameter,seed index,grain per head and 100-grain yield per plant.While RHP-53,RHP-42,RHP-46 were also the best combiners for all the traits.However,hybrid 54CMS-1 x RHP-42 showed best specific combiners,while Peshawer-93 exhibited good specific combiners for grain yield per plant,the hybrids,plant height,head diameter,seed index,grain per head and grain yield per plant,respectively.Significant differences among the tested sunflower genotypes with regard to mean values of all the investigated traits were determined.The analysis of variance of combining abilities and the analysis of genetic variance components confirmed the non-additive component. 展开更多
关键词 Line X tester HETEROSIS Combining ability SUNFLOWER
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Genetic gain and inbreeding from simulation of different genomic mating schemes for pig improvement 被引量:1
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作者 Fuping Zhao Pengfei Zhang +4 位作者 Xiaoqing Wang Deniz Akdemir Dorian Garrick Jun He Lixian Wang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第4期1363-1376,共14页
Background Genomic selection involves choosing as parents those elite individuals with the higher genomic estimated breeding values(GEBV)to accelerate the speed of genetic improvement in domestic animals.But after mul... Background Genomic selection involves choosing as parents those elite individuals with the higher genomic estimated breeding values(GEBV)to accelerate the speed of genetic improvement in domestic animals.But after multi-generation selection,the rate of inbreeding and the occurrence of homozygous harmful alleles might increase,which would reduce performance and genetic diversity.To mitigate the above problems,we can utilize genomic mating(GM)based upon optimal mate allocation to construct the best genotypic combinations in the next generation.In this study,we used stochastic simulation to investigate the impact of various factors on the efficiencies of GM to optimize pairing combinations after genomic selection of candidates in a pig population.These factors included:the algorithm used to derive inbreeding coefficients;the trait heritability(0.1,0.3 or 0.5);the kind of GM scheme(focused average GEBV or inbreeding);the approach for computing the genomic relationship matrix(by SNP or runs of homozygosity(ROH)).The outcomes were compared to three traditional mating schemes(random,positive assortative or negative assortative matings).In addition,the performance of the GM approach was tested on real datasets obtained from a Large White pig breeding population.Results Genomic mating outperforms other approaches in limiting the inbreeding accumulation for the same expected genetic gain.The use of ROH-based genealogical relatedness in GM achieved faster genetic gains than using relatedness based on individual SNPs.The GROH-based GM schemes with the maximum genetic gain resulted in 0.9%-2.6%higher rates of genetic gainΔG,and 13%-83.3%lowerΔF than positive assortative mating regardless of heritability.The rates of inbreeding were always the fastest with positive assortative mating.Results from a purebred Large White pig population,confirmed that GM with ROH-based GRM was more efficient than traditional mating schemes.Conclusion Compared with traditional mating schemes,genomic mating can not only achieve sustainable genetic progress but also effectively control the rates of inbreeding accumulation in the population.Our findings demonstrated that breeders should consider using genomic mating for genetic improvement of pigs. 展开更多
关键词 Genetic gain Genomic mating Genomic selection INBREEDING PIG
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Protective Effect of Silent Mating Type Information Regulation 2 Homolog 1 on TGF-β1 Pathway via mTOR in Diabetic Nephropathy
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作者 Yanting Gu Dechun Jiang +1 位作者 Pengcheng Xu Yanchun Wang 《Journal of Biosciences and Medicines》 CAS 2023年第2期194-207,共14页
Objective: To demonstrate whether the expression of silent mating type information regulation 2 homolog 1 (SIRT1) affects the level of TGF-β1 and Smad3 in HEK293 cells through regulating mTOR. Methods: First, recombi... Objective: To demonstrate whether the expression of silent mating type information regulation 2 homolog 1 (SIRT1) affects the level of TGF-β1 and Smad3 in HEK293 cells through regulating mTOR. Methods: First, recombinant plasmids DNA (rSIRT1) and siRNA targeting SIRT1 were constructed which were transfected into Human Embryonic Kidney 293 cell (HEK293) cells, respectively. Then, the generation of intracellular ROS in cells was examined by flow cytometry using the oxidation-sensitive probe. Last, the expressions of TGF-β1, smad3, P53, mTOR, p-mTOR, LC3-I and LC3-II in cells were detected to observe the effect of SIRT1 on TGF-β1 Pathway by western blot analysis. Results: We demonstrated that overexpressing of SIRT1 may decrease TGF-β1 and Smad3 expression in HEK293 cells through regulating mTOR. In addition, the result is the opposite when SIRT1 was silent in HEK293 cells. Conclusions: SIRT1 is closely related to TGF-β1/Smad3 pathway that correlates with the regulation of mTOR and ROS generation and causes diabetic nephropathy. The available evidence implies that SIRT1 has great potential as a clinical target for the prevention and treatment of renal fibrosis in the development of DN. 展开更多
关键词 Silent mating Type Information Regulation 2 Homolog 1 MTOR Diabetic Nephropathy AUTOPHAGY Oxidative Stress
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基于MATE的“前景-成本”体系建设方案智能选择框架
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作者 张玉婷 杨镜宇 《指挥控制与仿真》 2023年第6期1-6,共6页
战略评估是军事战略体系和能力建设的关键环节,对体系建设方案进行选择评估能够在一定程度上优化战略决策,提升战略管理水平。因此,构建了基于MATE的“前景-成本”体系建设方案智能选择分析框架,采用NSGA-Ⅱ智能优化算法在多维权衡空间... 战略评估是军事战略体系和能力建设的关键环节,对体系建设方案进行选择评估能够在一定程度上优化战略决策,提升战略管理水平。因此,构建了基于MATE的“前景-成本”体系建设方案智能选择分析框架,采用NSGA-Ⅱ智能优化算法在多维权衡空间中寻找备选方案的Pareto前沿,改善了数据量大的问题,并以某联合作战体系为例,验证了所提出方法的有效性,为体系建设方案的优选和评估提供理论支撑。 展开更多
关键词 体系建设 方案选择 多属性权衡空间探索 前景理论 NSGA-Ⅱ PARETO前沿
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Genome-wide identification of the MATE gene family and functional characterization of PbrMATE9 related to anthocyanin in pear
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作者 Jiawen Sheng Xuening Chen +4 位作者 Bobo Song Hainan Liu Jiaming Li Runze Wang Jun Wu 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第6期1079-1094,共16页
Plant multidrug and toxic compound extrusion(MATE) genes play an important role in the process of detoxification, plant morphogenesis, and anthocyanin accumulation. However, whether the MATE gene family functions in p... Plant multidrug and toxic compound extrusion(MATE) genes play an important role in the process of detoxification, plant morphogenesis, and anthocyanin accumulation. However, whether the MATE gene family functions in pear peel coloration is still unknown. To evaluate and identify the MATE gene family members which are involving in anthocyanin accumulation and coloration in pear. In this study, 85 MATE genes were identified in the reference pear genome of ‘Dangshansuli’ through genome-wide identification. Based on gene structure and phylogenetic tree analysis, the MATE family was divided into five subfamilies. RNA sequencing and quantitative real-time polymerase chain reaction(qRTPCR) indicated that the expression patterns of PbrMATEs were tissue-specific. 28.24%(24) of PbrMATE genes were expressed in the fruits, and44.71%(38) of PbrMATE genes were expressed in the leaves. Additionally, we found that the expression levels of PbrMATE9, PbrMATE26,PbrMATE50, and PbrMATE69 in debagged fruits with red peel were significantly higher than those in bagged fruits without red peel, according to our bagging/debagging treatment of ‘Mantianhong’. The expression pattern of PbrMATE9 was consistent with the variation trend in anthocyanin content, suggesting that it might play an important role in anthocyanin accumulation in response to light exposure. Subcellular localization showed that PbrMATE9 was a membrane protein. More strikingly, the transient overexpression of PbrMATE9 promoted anthocyanin accumulation in the peel of pear, and the expression of structural genes(PbrCHI, PbrANS, PbrDFR, and PbrUFGT) in the anthocyanin biosynthesis pathway also increased significantly. Through co-expression network analysis, the transcription factors were identified, such as WRKY, COL,GATA, and BBX, which might be involved in the regulation of PbrMATE9. The study has enriched the genetic resources and improved the understanding of the regulation network of anthocyanin accumulation in pear. 展开更多
关键词 PEAR ANTHOCYANIN COLORATION MATE gene family PbrMATE9 RNA-SEQ
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A single nucleotide substitution in the MATE transporter gene regulates plastochron and the many noded dwarf phenotype in barley(Hordeum vulgare L.)
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作者 GUO Bao-jian SUN Hong-wei +9 位作者 QI Jiang HUANG Xin-yu HONG Yi HOU Jian Lü Chao WANG Yu-lin WANG Fei-fei ZHU Juan GUO Gang-gang XU Ru-gen 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第8期2295-2305,共11页
In higher plants,the shoot apical meristem produces lateral organs in a regular spacing(phyllotaxy)and timing(plastochron).The molecular analysis of mutants associated with phyllotaxy and plastochron would increase ou... In higher plants,the shoot apical meristem produces lateral organs in a regular spacing(phyllotaxy)and timing(plastochron).The molecular analysis of mutants associated with phyllotaxy and plastochron would increase our understanding of the mechanism of shoot architecture formation.In this study,we identified mutant mnd8ynp5 that shows an increased rate of leaf emergence and a larger number of nodes in combination with a dwarfed growth habit from an EMS-treated population of the elite barley cultivar Yangnongpi 5.Using a map-based cloning strategy,the mnd8 gene was narrowed down to a 6.7-kb genomic interval on the long arm of chromosome 5H.Sequence analysis revealed that a C to T single-nucleotide mutation occurred at the first exon(position 953)of HORVU5Hr1G118820,leading to an alanine(Ala)to valine(Val)substitution at the 318th amino acid site.Next,HORVU5Hr1G118820 was defined as the candidate gene of MND8 encoding 514 amino acids and containing two multidrug and toxic compound extrusion(MATE)domains.It is highly homologous to maize Bige1and has a conserved function in the regulation of plant development by controlling the leaf initiation rate.Examination of modern barely varieties showed that Hap-1 was the dominant haplotype and was selected in barley breeding around the world.Collectively,our results indicated that mnd8ynp5 is a novel allele of the HORVU5Hr1G118820 gene that is possibly responsible for the shortened plastochron and many noded dwarf phenotype in barley. 展开更多
关键词 BARLEY EMS plastochron many noded dwarf MATE transporter shoot architecture
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核桃MATE基因家族成员挖掘与响应冷胁迫基因筛选
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作者 孙夕 李洋 +3 位作者 冯会 陈春晴 刘凯 李庆军 《落叶果树》 2023年第2期17-23,共7页
为阐明MATE家族在核桃响应冷害过程中扮演的角色,利用生物信息学技术从核桃基因组数据库中挖掘MATE家族成员,进一步分析其理化性质,结合转录数据分析MATE成员的表达模式。结果表明,核桃MATE家族共40个成员,开放阅读框为837~1741 bp,编... 为阐明MATE家族在核桃响应冷害过程中扮演的角色,利用生物信息学技术从核桃基因组数据库中挖掘MATE家族成员,进一步分析其理化性质,结合转录数据分析MATE成员的表达模式。结果表明,核桃MATE家族共40个成员,开放阅读框为837~1741 bp,编码的蛋白长度为278~589个氨基酸,等电点4.82~8.94,均为亲水性稳定蛋白;在冷害不同时间后经转录表达分析,JrMATE25转录水平较高,在雌花、老叶、嫩叶里面转录水平较高,推测可能响应冷害胁迫和花、叶器官的生长发育。 展开更多
关键词 核桃 多药与毒性化合物排出转运蛋白 冷害 时空
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高剂量性信息素环境对草地贪夜蛾求偶和交配行为的影响
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作者 黄丽丽 刘振东 +3 位作者 赵小英 杨志刚 郭前爽 杜永均 《植物保护》 CAS CSCD 北大核心 2024年第2期85-92,171,共9页
本文在风洞中模拟形成高浓度性信息素Z7-12:Ac、Z9-14:Ac和Z11-16:Ac环境,研究草地贪夜蛾Spodoptera frugiperda(Smith)的求偶和交配行为,为进一步开发交配干扰技术提供技术参数和依据。研究结果表明,在高剂量性信息素环境下,草地贪夜... 本文在风洞中模拟形成高浓度性信息素Z7-12:Ac、Z9-14:Ac和Z11-16:Ac环境,研究草地贪夜蛾Spodoptera frugiperda(Smith)的求偶和交配行为,为进一步开发交配干扰技术提供技术参数和依据。研究结果表明,在高剂量性信息素环境下,草地贪夜蛾雄蛾的暗期活动时间延后,而雌蛾的活动节律则没有变化,雌雄蛾之间产生了活动节律的时间差。同时,雌雄交配率和交配持续时间显著下降,交配日龄则显著延迟2 d。由于交配日龄延迟,产卵量及其孵化率也相应降低。性信息素喷射时间间隔对草地贪夜蛾性信息素释放滴度有显著影响,当间隔时间为5、10、20 min时,雌蛾释放的性信息素滴度显著下降,以5 min为最低。因此,高剂量性信息素环境不仅影响雄蛾对性信息素的定向,对雌雄蛾间化学通讯和交配也有显著影响。 展开更多
关键词 草地贪夜蛾 性信息素 交配干扰 求偶 交配
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水生甲壳动物性外激素研究现状与发展方向
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作者 张东 刘鑫 《海洋与湖沼》 CAS CSCD 北大核心 2024年第3期537-545,共9页
性外激素参与水生甲壳动物交配前识别与配偶选择。了解水生甲壳动物性外激素的化学特性对于解析其繁殖过程中化学通讯机理至关重要。对于蜕壳交配的物种而言,分析其交配和蜕壳阶段分泌的化学物质将有助于解读水生甲壳动物性外激素的演... 性外激素参与水生甲壳动物交配前识别与配偶选择。了解水生甲壳动物性外激素的化学特性对于解析其繁殖过程中化学通讯机理至关重要。对于蜕壳交配的物种而言,分析其交配和蜕壳阶段分泌的化学物质将有助于解读水生甲壳动物性外激素的演化。水生甲壳动物性外激素分为距离性外激素和接触性外激素两种,前者为水溶性的化合物;后者不溶于水,存在于甲壳动物体表。近年来,尿苷-5’-三磷酸,尿苷-5’-二磷酸和N-乙酰基-氨基-1,5-葡糖胺被认为是十足目甲壳动物距离性外激素的主要组分,而接触性外激素则由亲脂性碳氢化合物组成。近年来关于甲壳动物性外激素化学特性研究取得了长足发展,但仍存在需要突破的瓶颈。文章梳理了水生甲壳动物性外激素研究进展及未来研究方向,以期为研究水生甲壳动物性外激素提供参考。 展开更多
关键词 甲壳动物 性外激素 交配 繁殖行为
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不同公母比对本交笼模式下种公鸡性行为影响的研究
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作者 张姚 陈玉琪 +4 位作者 杜金花 齐莎日娜 李文艳 朱庆 尹华东 《中国畜禽种业》 2024年第6期54-60,共7页
为探究本交笼养模式下种公鸡的行为学特征,了解本交笼种公鸡的行为习惯。该试验在本交笼模式下选择594只50周龄的罗曼粉蛋种鸡,随机分为2组,每组3个重复,每个重复99只鸡,试验1、 2组公母比分别为1∶8和1∶10,连续1周观察各处理组种公鸡... 为探究本交笼养模式下种公鸡的行为学特征,了解本交笼种公鸡的行为习惯。该试验在本交笼模式下选择594只50周龄的罗曼粉蛋种鸡,随机分为2组,每组3个重复,每个重复99只鸡,试验1、 2组公母比分别为1∶8和1∶10,连续1周观察各处理组种公鸡的行为,并进行记录和分类统计。结果表明:本交笼养蛋种鸡的交配活动显著发生在下午,同时试验组1鸡只交配频率显著高于试验组2 (P<0.05)。鸡只在一天开灯时间内交配频率的时间分布结果显示,鸡只的交配频率主要集中在16:00—19:00,试验组1在17:00—18:00的交配频率显著高于试验组2 (P<0.05),在18:00—19:00的交配频率则极显著低于试验组2 (P<0.01)。试验组1中公鸡体重略低于试验组2,均匀度和平均交配次数高于试验组2,但差异不显著(P>0.05)。对种公鸡的等级进行划分,试验组1等级地位较高的种公鸡体型偏小,而试验组2等级地位较高的种公鸡体型则偏大;剔除笼内无效种公鸡后,种蛋受精率显著提高(P<0.05)。可见,试验组1种公鸡的均匀度和配种能力要优于试验组2。 展开更多
关键词 本交笼 种公鸡 交配行为 公母比
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基于ISSR-PCR体系鉴别樟芝单核体交配型
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作者 李晓晖 盖舒萍 +5 位作者 汪雯翰 琚建伟 张守兵 丁保安 李燕 贾薇 《中国食用菌》 2024年第2期68-75,共8页
通过原生质体单核化技术获得樟芝单核体,基于内转录间隔区(internal transcribed spacer,ITS)序列进行鉴定,采用14个引物对简单重复序列区间(inter-simple sequence repeats,ISSR)进行多态性扩增,筛选条带清晰、重复性好的引物用于樟芝... 通过原生质体单核化技术获得樟芝单核体,基于内转录间隔区(internal transcribed spacer,ITS)序列进行鉴定,采用14个引物对简单重复序列区间(inter-simple sequence repeats,ISSR)进行多态性扩增,筛选条带清晰、重复性好的引物用于樟芝单核体的交配型鉴定。结果表明,通过原生质体单核化技术获得31个樟芝单核体,经ITS序列分析确定获得的单核体为樟芝。以单核体S2、S10、S14、S27的DNA为模板,对14条ISSR引物进行初步筛选,得到4个条带清晰、重复性好的引物P7、P9、P21、P25用于交配型鉴定。单核体S9和S25为同一交配型,两者与S2为不同交配型,通过镜检进一步验证S9、S25可以与S2形成具有锁状联合的双核菌株。该方法可明显缩短樟芝单核体交配型的鉴定时间。 展开更多
关键词 樟芝 单核体 交配型 ISSR ITS
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眩晕的经络相关性研究
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作者 刘婕 姜敏 冯兴中 《现代中西医结合杂志》 CAS 2024年第8期1077-1080,1145,共5页
目的观察眩晕患者的中医经络检测仪能量值的变化,探讨中医经络能量值与眩晕的相关性。方法选取2021年3月—2022年3月于北京世纪坛医院门诊及住院诊治的106例眩晕患者为研究组,以同期健康受试者117例为对照组,采用中医经络检测仪对2组受... 目的观察眩晕患者的中医经络检测仪能量值的变化,探讨中医经络能量值与眩晕的相关性。方法选取2021年3月—2022年3月于北京世纪坛医院门诊及住院诊治的106例眩晕患者为研究组,以同期健康受试者117例为对照组,采用中医经络检测仪对2组受试者十二正经原穴经络能量值进行测量和比较,采用Logistic回归分析法对经络能量值和眩晕相关性进行分析。结果2组受试者的性别、年龄及十二正经原穴中冲阳(胃经)、太白(脾经)、神门(心经)、腕骨(小肠经)、太溪(肾经)、大陵(心包经)、阳池(三焦经)、丘虚(胆经)、太冲(肝经)能量值比较差异均无统计学意义(P均>0.05),而太渊(肺经)、阳溪(大肠经)、束骨(膀胱经)能量值比较差异均有统计学意义(P均<0.05)。Logistic回归分析显示,膀胱经能量偏低为眩晕的独立影响因素(OR=0.957,95%CI:0.923~0.991,P=0.014)。结论眩晕患者膀胱经能量低(束骨),肺经(太渊)及大肠经(阳溪)能量亢进,其他经络能量变化无规律可言,提示该病症的发生可能与膀胱经能量值异常相关。 展开更多
关键词 眩晕 经络 中医经络检测仪
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2种硬度检测方法在压力管道检验中的有效性对比
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作者 李志峰 杨利军 宋利滨 《管道技术与设备》 CAS 2024年第2期34-37,共4页
采用便携式里氏硬度计和实时压痕分析仪对不同材质、不同壁厚的试样进行了硬度检测。通过对比验证方法研究了布氏硬度压痕法和里氏硬度试验方法在相同试验条件下得到的硬度值,同时将实时压痕分析仪所得的材料力学性能数值与试验数据进... 采用便携式里氏硬度计和实时压痕分析仪对不同材质、不同壁厚的试样进行了硬度检测。通过对比验证方法研究了布氏硬度压痕法和里氏硬度试验方法在相同试验条件下得到的硬度值,同时将实时压痕分析仪所得的材料力学性能数值与试验数据进行对比。结果表明:实时压痕分析仪测得的数据更准确,稳定性高,重复性好;可以现场无损且较准确获得材料力学性能。 展开更多
关键词 实时压痕分析仪 有效性 压力管道检验 里氏硬度计
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性别比和自身资源对职场人士择偶线索偏好的影响
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作者 张璟 刘烁华 +1 位作者 郑沁婷 周双珠 《心理技术与应用》 2024年第1期1-9,共9页
采用择偶币范式,考察性别比背景和自身资源对职场人士择偶线索偏好的影响。结果发现:(1)当职场人士自身拥有较多资源时,性别比对其择偶线索偏好的影响较小;(2)无论处于何种环境,爱情均为职场人士择偶的必需品,未来收入前景为奢侈品;(3)... 采用择偶币范式,考察性别比背景和自身资源对职场人士择偶线索偏好的影响。结果发现:(1)当职场人士自身拥有较多资源时,性别比对其择偶线索偏好的影响较小;(2)无论处于何种环境,爱情均为职场人士择偶的必需品,未来收入前景为奢侈品;(3)当职场人士处于性别比劣势环境时,其择偶的必需品还包括真诚善良、忠贞和身体健康。可见,职场人士的择偶线索偏好受内外部因素的共同影响。 展开更多
关键词 性别比 自身资源 择偶线索偏好 职场人士
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基于不同搜索路径下成对随机游走的推荐算法
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作者 耿秀丽 牛璐 《计算机集成制造系统》 EI CSCD 北大核心 2024年第4期1389-1396,共8页
推荐系统中用户项目之间的交互及其他信息可以构成一个异构信息网络(HIN)。传统基于HIN的推荐算法往往直接构建用户项目间的异构信息网络,忽略了用户用户以及项目项目本身具有的相似性,所构建的网络不够完整,并且在计算节点关联性时鲜... 推荐系统中用户项目之间的交互及其他信息可以构成一个异构信息网络(HIN)。传统基于HIN的推荐算法往往直接构建用户项目间的异构信息网络,忽略了用户用户以及项目项目本身具有的相似性,所构建的网络不够完整,并且在计算节点关联性时鲜有考虑不同搜索路径下的不同关联性。为解决上述问题,提出一种考虑用户及项目本身相似性的HIN推荐算法。通过查找用户与项目之间更多的搜索路径,并考虑不同的搜索路径,引入深度学习中的随机游走(RW)来度量用户项目节点之间的关联度,从而实现更加精确的推荐。将所提算法在公开的MovieLens数据集上进行了实验,实验结果表明:相较于传统的协同过滤推荐算法以及基于HIN的推荐算法,基于不同搜索路径下成对随机游走的算法具有更高的推荐性能。 展开更多
关键词 推荐系统 异构信息网络 元路径 随机游走 Hete Sim
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观赏蕨类姬蕨同配子体自交的孢子体萌发和发育特性
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作者 李莉 杨春萍 商辉 《园艺与种苗》 CAS 2024年第1期15-18,共4页
[目的]评估交配形式对蕨类繁殖的影响。[方法]以姬蕨(Hypolepis punctata)为例,设计配子体单独培养(同配自交)和混合培养(混交)比较试验,比较两种交配系统下孢子体萌发状态(萌发率、存活率),孢子体成长情况及生长速率。[结果]尽管自交... [目的]评估交配形式对蕨类繁殖的影响。[方法]以姬蕨(Hypolepis punctata)为例,设计配子体单独培养(同配自交)和混合培养(混交)比较试验,比较两种交配系统下孢子体萌发状态(萌发率、存活率),孢子体成长情况及生长速率。[结果]尽管自交幼苗生长趋势弱于混交个体,单独培养产生的完全纯合的姬蕨孢子体最终存活率达到62.5%,说明蕨类的自交确实可以导致近交衰退,但仍然具有可接受的存活能力,单个孢子仍有很大概率上延续种群。蕨类植物由于其特殊的生活史特性,可通过单独培养得到完全纯合的自交个体,从而得到性状稳定的品系。[结论]该研究中单独培养技术在园艺育种方向具有很好的应用前景。 展开更多
关键词 蕨类植物 孢子培养 交配系统 纯合子 近交衰退 自交系
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立式去污测定仪校准方法研究
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作者 王鹏 陶笑昱 程葆明 《现代科学仪器》 2024年第1期28-31,共4页
立式去污测定仪是进行去污试验评价洗涤剂去污力的专用设备,主要应用于洗涤剂产品研发、测试及洗涤剂去污力和抗污渍再沉积能力试验等方面。针对目前国内市场尚无该设备的国家校准规范,该文从立式去污测定仪的物理性能出发,探讨该仪器... 立式去污测定仪是进行去污试验评价洗涤剂去污力的专用设备,主要应用于洗涤剂产品研发、测试及洗涤剂去污力和抗污渍再沉积能力试验等方面。针对目前国内市场尚无该设备的国家校准规范,该文从立式去污测定仪的物理性能出发,探讨该仪器的计量特性和校准方法,提出适用于该仪器的校准项目和技术指标。为验证该方法,以RHLQ-III型立式去污测定仪为实验对象,对温度偏差、温度波动度、温度均匀度、转速示值相对误差、定时相对误差5个项目进行校准试验。实验结果表明该校准方法准确可靠,有助于计量检定机构开展立式去污测定仪的校准工作。 展开更多
关键词 去污仪 计量 校准方法
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铝合金板冲压摩擦试验机开发与试验
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作者 李小强 张贺刚 +3 位作者 王烁 李高峰 孟庆阔 张永生 《北京航空航天大学学报》 EI CAS CSCD 北大核心 2024年第6期1898-1910,共13页
针对铝合金板冲压成形对摩擦测试的需求,确定考虑加热条件下铝合金板材冲压摩擦伺服压力摩擦测试平台的总体设计方案,开发适用于铝合金板材成形的小载荷高精度多功能摩擦试验机系统。该系统由运动组件、加热系统及控制系统组成。运动组... 针对铝合金板冲压成形对摩擦测试的需求,确定考虑加热条件下铝合金板材冲压摩擦伺服压力摩擦测试平台的总体设计方案,开发适用于铝合金板材成形的小载荷高精度多功能摩擦试验机系统。该系统由运动组件、加热系统及控制系统组成。运动组件实现上模具和夹头的运动支撑;加热系统实现模具与试件单独加热;在伺服控制模式下,结合外部力传感器和光栅尺,实现试件压力和模具间隙高精度高稳定性控制。实际应用检验该试验机对不同因素的区分度和重复性,并设计正交试验,探索不同因素对铝合金板材摩擦的影响。结果表明:试验机性能稳定,重复性好;影响摩擦系数因素的重要次序为:模具温度、压力、速度、润滑剂;温度越低,压力越大,速度越快,摩擦系数越小;同一种类型的润滑剂对摩擦系数的影响较小。随着压力的增大,摩擦系数减少的趋势越来越小,逐渐趋于平稳。 展开更多
关键词 摩擦试验机 铝合金板冲压 伺服控制 摩擦试验 摩擦学行为
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