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平凉红牛高效繁育技术及应用效果

天津农林科技 2024年第2期 29-33页

作者：张盛南孙广坤马晨龙王永颖郭爽王鸿英天津市农业发展服务中心天津300061 天津天食牛种业有限公司天津301902 庄浪县畜牧兽医中心甘肃平凉744699

为提高甘肃省平凉市庄浪县平凉红牛的繁育水平,文章从牛发情鉴定技术、配种管理技术、妊娠诊断管理技术入手,提出适合平凉红牛品种特性及庄浪县养殖现状的平凉红牛高效繁育技术,包括牛发情鉴定、配种时间、冻精选择、人工输精、妊娠诊... 详细信息

为提高甘肃省平凉市庄浪县平凉红牛的繁育水平,文章从牛发情鉴定技术、配种管理技术、妊娠诊断管理技术入手,提出适合平凉红牛品种特性及庄浪县养殖现状的平凉红牛高效繁育技术,包括牛发情鉴定、配种时间、冻精选择、人工输精、妊娠诊断等技术要点,在甘肃省平凉市庄浪县开展试验示范。应用平凉红牛高效繁育技术后,示范点的母牛发情揭发率、参配率、受胎率、21d受胎率较应用技术前均有所提高,平均配孕天数、妊娠平均精液消耗、18月龄未孕牛、半年不孕牛、流产牛等指标均有所下降。

关键词：平凉红牛肉牛繁育技术应用效果

婴幼儿配方奶粉中1,3-二油酸-2-棕榈酸甘油三酯的测定

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中国乳业 2024年第4期 67-71页

作者：徐旖陈小丽王潇陈双吕晓蓉汤陈龙孟奇浙江公正检验中心有限公司浙江杭州310009 浙江省食品安全重点实验室浙江杭州310009

[目的]建立气相色谱检测婴幼儿配方奶粉中1,3-二油酸-2-棕榈酸甘油三酯的含量。[方法]婴幼儿配方奶粉样品经温水溶解、氨水皂化、乙醚石油醚提取油脂,正己烷溶解,采用Agilent DB-1HT毛细管柱分离,通过与标准甘油三酯溶液对比确定出峰位... 详细信息

[目的]建立气相色谱检测婴幼儿配方奶粉中1,3-二油酸-2-棕榈酸甘油三酯的含量。[方法]婴幼儿配方奶粉样品经温水溶解、氨水皂化、乙醚石油醚提取油脂,正己烷溶解,采用Agilent DB-1HT毛细管柱分离,通过与标准甘油三酯溶液对比确定出峰位置,采用内标法定量。[结果]方法定量限为0.008 mg/100 g,线性范围良好。低、中、高3个标准添加水平的回收率为81.1%~98.4%,相对标准偏差在2.89%~7.88%。对婴幼儿配方羊奶粉、牛奶粉基质样品中1,3-二油酸-2-棕榈酸甘油三酯的含量测定RSD≤3.03%。[结论]该方法操作过程简单、分析周期短、灵敏度高、重复性好,适用于测定婴幼儿配方牛奶粉、婴幼儿配方羊奶粉中1,3-二油酸-2-棕榈酸甘油三酯的含量,具有理想的定量效果及应用前景。

关键词：气相色谱 1,3-二油酸-2-棕榈酸甘油三酯婴幼儿配方奶粉

Identification and validation of key biomarkers and potential therapeutic targets for primary open-angle glaucoma

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Science China(Life Sciences) 2023年第12期66卷 2837-2850页

作者： Jian Wu Caixia Lin chenlong Yang Lijie Pan Hongyi Liu Sirui Zhu Shuwen Wei Xu Jia Qi Zhang Ziyu Yu Xiaofang Zhao Weihai Liu Yehong Zhuo Ningli wang Beijing Institute of Ophthalmology Beijing Tongren Eye CenterBeijing Tongren HospitalCapital Medical UniversityBeijing Key Laboratory of Ophthalmology and Visual SciencesBeijing 100730China Beijing Tongren Eye Center Beijing Tongren HospitalCapital Medical UniversityBeijing 100730China Department of Neurosurgery Peking University Third HospitalCenter for Precision Neurosurgery and Oncology of Peking University Health Science CenterBeijing 100191China North America Medical Education Foundation Union City CA 94539USA State Key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-sen UniversityGuangzhou 510060China Spencer Center for Vision Research Byers Eye InstituteSchool of MedicineStanford UniversityPalo Alto CA 94304USA

Primary open-angle glaucoma(POAG)is a prevalent cause of blindness worldwide,resulting in degeneration of retinal ganglion cells and permanent damage to the optic nerve.However,the underlying pathogenetic mechanisms of POAG are currently indistinct,and there has been no effective nonsurgical treatment regimen.The objective of this study is to identify novel biomarkers and potential therapeutic targets for POAG.The mRNA expression microarray datasets GSE27276 and GSE138125,as well as the single-cell high-throughput RNA sequencing(sc RNA-seq)dataset GSE148371 were utilized to screen POAGrelated differentially expressed genes(DEGs).Functional enrichment analyses,protein-protein interaction(PPI)analysis,and weighted gene co-expression network analysis(WGCNA)of the DEGs were performed.Subsequently,the hub genes were validated at a single-cell level,where trabecular cells were annotated,and the mRNA expression levels of target genes in different cell clusters were analyzed.Immunofluorescence and quantitative real-time PCR(q PCR)were performed for further validation.DEGs analysis identified 43 downregulated and 32 upregulated genes in POAG,which were mainly enriched in immune-related pathways,oxidative stress,and endoplasmic reticulum(ER)stress.PPI networks showed that FN1 and DUSP1 were the central hub nodes,while GPX3 and VAV3 were screened out as hub genes through WGCNA and subsequently validated by q PCR.Finally,FN1,GPX3,and VAV3 were determined to be pivotal core genes via single-cell validation.The relevant biomarkers involved in the pathogenesis of POAG,may serve as potential therapeutic targets.Further studies are necessary to unveil the mechanisms underlying the expression variations of these genes in POAG.

关键词： primary open-angle glaucoma biomarkers immune response oxidative stress endoplasmic reticulum stress

联合检测MA、BUN、sCr、eGFR在他克莫司致移植肾早期损伤发生中的诊断价值

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中华全科医学 2024年第3期22卷 478-480,494页

作者：王浩赖大海黄帅帅金爱慧许沉龙岑东宁波市泌尿肾病医院检验科浙江宁波315100 宁波市泌尿肾病医院肾病研究所

目的联合检测尿微量白蛋白(MA)、血尿素氮(BUN)、血肌酐(sCr)和估算的肾小球滤过率(eGFR)在评估肾移植后患者因使用他克莫司(Tac)所致的移植肾功能损伤早期发现的临床价值。方法选取2015年8月—2020年7月宁波市泌尿肾病医院收治的长... 详细信息

目的联合检测尿微量白蛋白(MA)、血尿素氮(BUN)、血肌酐(sCr)和估算的肾小球滤过率(eGFR)在评估肾移植后患者因使用他克莫司(Tac)所致的移植肾功能损伤早期发现的临床价值。方法选取2015年8月—2020年7月宁波市泌尿肾病医院收治的长期使用Tac的肾移植患者54例,同一患者根据Tac持续使用的时间分为12个月组(A组)、24个月组(B组)进行比较分析,以评估MA、BUN、sCr、eGFR以及联合检测的临床价值。结果比较发现,B组MA、eGFR较A组差异均有统计学意义(P0.05)。eGFR与MA、BUN、sCr均呈负相关关系[用药12个月组(A组)和用药24个月(B组)r值分别为-0.413、-0.538、-0.797(P<0.01)和-0.333、-0.647、-0.738(P<0.05)],且与Tac持续使用时间具有相关性,在移植后早期相关性更为显著。受试者工作特征曲线显示,MA、BUN、sCr、eGFR单独检测的AUC分别为0.680、0.594、0.581、0.689,4项指标联合检测时AUC为0.839。结论 MA、BUN、sCr、eGFR四项肾功能损伤标志物联合检测对肾移植后持续使用Tac患者肾功能损伤的发生具有早期诊断价值。

关键词：肾移植肾功能损伤他克莫司标志物联合检测

Crosstalk between PC 12 cells and endothelial cells in an artificial neurovascular niche constructed by a dual-functionalized selfassembling peptide nanofiber hydrogel

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Nano Research 2022年第2期15卷 1433-1445页

作者： Zhe Zhang Yi Chai He Zhao Shuhui Yang Wei Liu Zihui Yang Weilong Ye chenlong wang Xiaohan Gao Xiangdong Kong Xiaodan Sun Lingyun Zhao Tuoyu Chen Yuqi Zhang Jiaju Lu Xiumei wang State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Department of Neurosurgery Yuquan HospitalSchool of Clinical MedicineTsinghua UniversityBeijing 100084China Institute of Smart Biomedical Materials School of Materials Science and EngineeringZhejiang Sci-Tech UniversityHangzhou 310018China Department of orthopedics Dongzhimen hospitalBeijing University of Chinese MedicineBeijing 100700China Department of Neurosurgery The First Hospital of Hebei Medical UniversityShijiazhuang 050000China Department of Obstetrics and Gynecology Beijing Tsinghua Changgung HospitalBeijing 102218China Department of Chemistry Tsinghua UniversityBeijing 100084China

The coordination between neurogenesis and angiogenesis plays an important role in nerve tissue development and regeneration.Recently,using bioactive materials to drive neurogenic and angiogenic responses has gained increasing attention.Understanding the neurovascular link between regulatory cues offers valuable insight into the mechanisms underlying nerve regeneration and the design of new bioactive materials.In this study,we utilized a dual-functionalized peptide nanofiber hydrogel presenting the brain-derived neurotrophic factor and vascular endothelial growth factor mimetic peptides RGIDKRHWNSQ(RGI)and KLTWQELYQLKYKGI(KLT)to construct an artificial neurovascular microenvironment.The dual-functionalized peptide nanofiber hydrogel enhanced the neurite outgrowth of pheochromocytoma(PC12)cells and tube-like structures formation of human umbilical vein endothelial cells(HUVECs)in vitro,and promoted rapid lesion infiltration of neural and vascular cells in a rat brain injury model.Using indirect co-culture models,we found that the dual-functionalized peptide hydrogel effectively mediated neurovascular crosstalk by regulating secretion of paracrine factors from PC12 cells and HUVECs.When the two cells types were directly co-cultured on the dua卜functionalized peptide hydrogel,the efficiency of cell-cell communication was enhanced,which further accelerated the differentiation and maturation of PC12 cells with an increased number of pseudopodia and spread morphology,and HUVECs tube-like structure formation.In summary,the dual-functionalized peptide nanofiber hydrogel successfully formed an artificial neurovascular niche to directly regulate the behaviors of neural and vascular cells and promote their neurovascular crosstalk through paracrine signaling and direct cell-cell contact.

关键词： neurovascular microenvironment self-assembling peptide co-culture nanofiber hydrogel brain injury

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乳化橡胶沥青蒸发残留物流变性能研究

石油沥青 2024年第2期38卷 41-47页

作者：李辰王晨龙任海庆宋晓庆孟伟坤武文鑫赵品晖山东建筑大学交通工程学院济南250101 山东省高速养护集团有限公司济南250000 山东高速交通建设集团有限公司济南250000

乳化橡胶沥青蒸发残留物的流变性能决定了其路用性能。通过动态频率扫描试验、温度扫描试验、MSCR试验、低温蠕变试验,研究了乳化橡胶沥青蒸发残留物的流变性能并与乳化前橡胶沥青的性能进行了对比。结果表明:与橡胶沥青相比,乳化橡胶... 详细信息

乳化橡胶沥青蒸发残留物的流变性能决定了其路用性能。通过动态频率扫描试验、温度扫描试验、MSCR试验、低温蠕变试验,研究了乳化橡胶沥青蒸发残留物的流变性能并与乳化前橡胶沥青的性能进行了对比。结果表明:与橡胶沥青相比,乳化橡胶沥青蒸发残留物的复数剪切模量(G~*)、活化能(Ea)、存储模量(G′)、损失模量(G″)、失效温度变大,相位角(δ)降低,高温性能更好。恢复率(R)较大,不可恢复蠕变柔量(Jnr)降低,具有更加优异的高温抗车辙能力。蠕变劲度(S)较大,蠕变速率(m)较小,且在相同温度条件下S/m值更大,表明其低温性能降低。

关键词：橡胶沥青改性乳化沥青流变性能

Growth modulation of simultaneous epitaxy of ZnO obliquely aligned nanowire arrays and film on r-plane sapphire substrate

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Nano Research 2018年第7期11卷 3864-3876页

作者： Yongchun Xiao Yaoyao Tian Shujing sun chenlong Chen Buguo wang Key Laboratory of Optoelectronic Materials Chemistry and Physics Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences Fuzhou 350002 China College of Materials Science and Engineering Fujian Normal University Fuzhou 350007 China wSemiconductor Research Center Wright State University Dayton OH45431 USA

Simultaneous epitaxial growth of film and nanowire array on a substrate is of both scientific significance and practical importance for nanoscale optoelectronics. Nevertheless, in situ building conducting connection between individually isolated nanowires grown on insulating substrates is still challenging. Herein, we demonstrate a novel and facile strategy for the simultaneous epitaxial growth of nonpolar a-plane ZnO film and obliquely aligned nanowire array on Au-coated r-plane sapphire substrate. The morphology, structure, components, and optical properties of the as-synthesized ZnO nanostructures were investigated using field-emission scanning electron microscopy X-ray diffraction, field-emission transmission electron microscopy energy-dispersive spectroscopy, X-ray photo- electron spectroscopy, and photoluminescence spectroscopy. A cooperative growth mechanism is proposed： Au-catalyzed vapor transport initiates the co-occurrence of nonpolar a-plane and polar c-plane ZnO nuclei, and subsequently, the non-upward directed Au catalyst helps the nonpolar a-plane ZnO nuclei develop into a ZnO conductive film at the bottom and zinc self-catalyzed vapor-liquid-solid growth helps the polar c-plane ZnO nuclei develop simultaneously into obliquely aligned nanowire arrays. The proposed strategy realized in situ synthesis of nanowires with conductive connection and it can benefit the application of ZnO nanowires in optoelectronics.

关键词： ZnO obliquely aligned nanowire arrays non-polar thin film epitaxy zinc self-catalyzed

Hard nanocrystalline gold materials prepared via high-pressure phase transformation

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Nano Research 2022年第7期15卷 6678-6685页

作者： chenlong Xie Wenxin Niu Penghui Li Yiyao Ge Jiawei Liu Zhanxi Fan Xiaoxiao Liu Ye Chen Ming Zhou Zihe Li Mengdong Ma Yonghai Yue Jing wang Li Zhu Kun Luo Yang Zhang Yingju Wu Lin wang Bo Xu Hua Zhang Zhisheng Zhao Yongjun Tian Center for High Pressure Science(CHiPS) State Key Laboratory of Metastable Materials Science and TechnologyYanshan UniversityQinhuangdao 066004China Center for Programmable Materials School of Materials Science and EngineeringNanyang Technological UniversitySingapore 639798Singapore State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Department of Chemistry City University of Hong KongHong KongChina Hong Kong Branch of National Precious Metals Material Engineering Research Center(NPMM) City University of Hong KongHong KongChina Shenzhen Research Institute City University of Hong KongShenzhen 518057China Department of Chemistry The Chinese University of Hong KongHong KongChina School of Chemistry Beijing Advanced Innovation Center for Biomedical EngineeringBeihang UniversityBeijing 100190China Institute of Mechanics Chinese Academy of SciencesBeijing 100190China

As one of the important materials,nanocrystalline Au(n-Au)has gained numerous interests in recent decades owing to its unique properties and promising applications.However,most of the current n-Au thin films are supported on substrates,limiting the study on their mechanical properties and applications.Therefore,it is urgently desired to develop a new strategy to prepare nAu materials with superior mechanical strength and hardness.Here,a hard n-Au material with an average grain size of~40 nm is prepared by cold-forging of the unique Au nanoribbons(NRBs)with unconventional 4H phase under high pressure.Systematic characterizations reveal the phase transformation from 4H to face-centered cubic(fcc)phase during the cold compression.Impressively,the compressive yield strength and Vickers hardness(HV)of the prepared n-Au material reach~140.2 MPa and~1.0 GPa,which are 4.2 and 2.2 times of the microcrystalline Au foil,respectively.This work demonstrates that the combination of high-pressure cold-forging and the in-situ 4H-to-fcc phase transformation can effectively inhibit the grain growth in the obtained n-Au materials,leading to the formation of novel hard n-Au materials.Our strategy opens up a new avenue for the preparation of nanocrystalline metals with superior mechanical property.

关键词： nanocrystalline Au high hardness high strength high-pressure forging 4H Au nanoribbons

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非均匀温度场下枝晶生长状态

稀有金属材料与工程 2022年第10期51卷 3707-3715页

作者：秦勤叶陈龙谢璐王田北京科技大学机械工程学院北京100083 北京科技大学顺德研究生院广东佛山528000

为了掌握非均匀温度场下微观组织的演变规律,本工作采用改进的元胞自动机模型,在完成算法验证的基础上,对比微观组织在均匀温度场和非均匀温度场下组织演变的异同,并系统研究微观组织在非均匀温度场中的枝晶形貌、尖端生长速率和域内溶... 详细信息

为了掌握非均匀温度场下微观组织的演变规律,本工作采用改进的元胞自动机模型,在完成算法验证的基础上,对比微观组织在均匀温度场和非均匀温度场下组织演变的异同,并系统研究微观组织在非均匀温度场中的枝晶形貌、尖端生长速率和域内溶质分布以及多晶组织的演变规律。研究结果表明:该模型仿真结果与CA-FD模型结果误差范围在1.4%以内;枝晶凝固末端尖端速率在温度均匀场内趋于稳定,而在非均匀场内表现为持续上升;固相溶质浓度在非均匀场内随着枝晶臂的延展而增大,在均匀场内则保持不变。对于非均匀温度场内单枝晶生长,冷速达到10 K/s时,枝晶臂的长度达到1030μm,较均匀场增加49.3%,当冷速达到30 K/s时,枝晶臂长度达到1460μm,同比增加了111.6%;冷速的加强使枝晶内部固相溶质浓度增加,出现更多侧向枝晶臂,使固/液界面区域溶质出现波动,呈现不规则分布;多晶组织在非均匀温度场内平均溶质浓度随冷速的增大而上升,且域内合金在凝固结束后固相比例随冷速的增加由45%增加到65%,同时观察到域内溶质富集,多次枝晶臂的产生和枝晶臂粗化等现象。

关键词：元胞自动机枝晶生长非均匀温度场冷却速率