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COL4A2 enhances thyroid cancer cell proliferation through the AKT pathway
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作者 LIANG HE wei han +1 位作者 KAI YUE XUDONG WANG 《Oncology Research》 SCIE 2024年第9期1467-1478,共12页
Objectives:Thyroid cancer(THCA)is the most common malignant tumor in endocrine system and the incidence has been increasing worldwide.And the number of patients dying from THCA has also gradually risen because the inc... Objectives:Thyroid cancer(THCA)is the most common malignant tumor in endocrine system and the incidence has been increasing worldwide.And the number of patients dying from THCA has also gradually risen because the incidence continues to increase,so the mechanisms related to effective targets is necessary to improve the survival.This study was to preliminarily investigate the effects of the COL4A2 gene on the regulation of thyroid cancer(THCA)cell proliferation and the associated pathways.Methods:Bioinformatics analysis revealed that COL4A2 was closely associated with cancer development.COL4A2 expression in THCA tissues was analyzed using immunohistochemistry,and survival information was determined via Kaplan-Meier curves.The expression of COL4A2 and AKT pathway-related genes were analyzed using qPCR and western blot analyses.Colony formation as well as CCK-8 assays exhibited the cell proliferation level and cell activity,respectively.Downstream of COL4A2 was identified by Gene set enrichment analysis(GSEA).The effects of the COL4A2 and AKT pathways on THCA tumor growth in vivo were determined using a mouse model.Results:Bioinformatics analysis exhibited that COL4A2 plays a significant role in cancer and that the AKT pathway is downstream of COL4A2.THCA patients with high COL4A2 expression had shorter recurrence-free survival.Upregulation of COL4A2 gene expression in 2 THCA cell lines promoted tumor cell growth and activity.The use of AKT pathway blockers also restrained the growth and activity of the 2 THCA cell lines.The use of AKT pathway blockers reduced tumor volume and mass and prolonged mouse survival.Conclusions:COL4A2 can promote the growth as well as development of THCA through the AKT pathway and COL4A2 could be used as a target for THCA. 展开更多
关键词 Thyroid cancer(THCA) PROLIFERATION COL4A2 AKT pathway Biomarker cancer progression
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制造发展的三个范式:制造发展规律的研究 被引量:3
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作者 房丰洲 赖敏 +11 位作者 王金石 吕鹏 于楠 罗熙淳 胡春光 陈远流 陈磊 邓辉 徐涛 康城玮 韩伟 冯俊元 《中国科学基金》 CSSCI CSCD 北大核心 2024年第1期159-171,共13页
基于对人类社会发展历史和科学技术发展内在规律的认识,本文详细分析了制造发展的三个范式,论证了原子及近原子尺度制造是制造范式III的核心使能技术。文章回顾了国内外各机构对原子级制造研发规划现状,指出我国目前处于原子级制造技术... 基于对人类社会发展历史和科学技术发展内在规律的认识,本文详细分析了制造发展的三个范式,论证了原子及近原子尺度制造是制造范式III的核心使能技术。文章回顾了国内外各机构对原子级制造研发规划现状,指出我国目前处于原子级制造技术发展的重要战略机遇期,并从设计、材料、加工和检测等角度分析了原子级制造的技术体系内涵;梳理了原子级表面制造、原子级结构制造、原子级测量与表征等领域的研究进展,呈现了当前具有原子级制造能力的部分代表性技术,包括原子级切削、原子级抛光、电化学加工、等离子体原子级加工技术、原子精准操控以及原子分辨测量与表征技术,并对原子级制造战略规划提出发展建议。 展开更多
关键词 制造技术发展趋势 制造范式 原子及近原子尺度制造 原子精度制造 原子级制造
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Recent advances in energy storage mechanism of aqueous zinc-ion batteries 被引量:15
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作者 Duo Chen Mengjie Lu +2 位作者 Dong Cai hang Yang wei han 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第3期712-726,共15页
Aqueous rechargeable zinc-ion batteries(ZIBs)have recently attracted increasing research interest due to their unparalleled safety,fantastic cost competitiveness and promising capacity advantages compared with the com... Aqueous rechargeable zinc-ion batteries(ZIBs)have recently attracted increasing research interest due to their unparalleled safety,fantastic cost competitiveness and promising capacity advantages compared with the commercial lithium ion batteries.However,the disputed energy storage mechanism has been a confusing issue restraining the development of ZIBs.Although a lot of efforts have been dedicated to the exploration in battery chemistry,a comprehensive review that focuses on summarizing the energy storage mechanisms of ZIBs is needed.Herein,the energy storage mechanisms of aqueous rechargeable ZIBs are systematically reviewed in detail and summarized as four types,which are traditional Zn^(2+)insertion chemistry,dual ions co-insertion,chemical conversion reaction and coordination reaction of Zn^(2+)with organic cathodes.Furthermore,the promising exploration directions and rational prospects are also proposed in this review. 展开更多
关键词 Zinc-ion batteries Energy storage mechanism Rechargeable aqueous battery Zn-MnO_(2)battery Electrolytic battery
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Changes in the Proportion of Precipitation Occurring as Rain in Northern Canada during Spring–Summer from 1979–2015 被引量:5
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作者 wei han Cunde XIAO +1 位作者 Tingfeng DOU Minghu DING 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2018年第9期1129-1136,共8页
Changes in the form of precipitation have a considerable impact on the Arctic cryosphere and ecological system by influencing the energy balance and surface runoff. In this study, station observations and ERA-Interim ... Changes in the form of precipitation have a considerable impact on the Arctic cryosphere and ecological system by influencing the energy balance and surface runoff. In this study, station observations and ERA-Interim data were used to analyze changes in the rainfall to precipitation ratio(RPR) in northern Canada during the spring–summer season(March–July)from 1979–2015. Our results indicate that ERA-Interim describes the spring–summer variations and trends in temperature and the RPR well. Both the spring–summer mean temperature [0.4℃–1℃(10 yr)^(-1)] and the RPR [2%–6%(10 yr)^(-1)] increased significantly in the Canadian Arctic Archipelago from 1979–2015. Moreover, we suggest that, aside from the contribution of climate warming, the North Atlantic Oscillation is probably another key factor influencing temporal and spatial differences in the RPR over northern Canada. 展开更多
关键词 climate change rainfall to precipitation ratio northern Canada North Atlantic Oscillation
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Gold-leaching performance and mechanism of sodium dicyanamide 被引量:2
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作者 Gen-zhuang Li Jue Kou +4 位作者 Yi Xing Yang Hu wei han Zi-yuan Liu Chun-bao Sun 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2021年第11期1759-1768,共10页
In this work,sodium dicyanamide(SD)was used as a leaching reagent for gold recovery,and the effects of the SD dosage and solution pH on the gold-leaching performance were investigated.A gold recovery of 34.8%was obtai... In this work,sodium dicyanamide(SD)was used as a leaching reagent for gold recovery,and the effects of the SD dosage and solution pH on the gold-leaching performance were investigated.A gold recovery of 34.8%was obtained when SD was used as the sole leaching reagent at a dosage of 15 kg/t.In the presence of a certain amount of potassium ferrocyanide(PF)in the SD solution,the gold recovery was found to increase from 34.8%to 57.08%.Using the quartz crystal microbalance with dissipation(QCM-D)technique,the leaching kinetics of SD with and without PF were studied.The QCM-D results indicate that the gold-leaching rate increased from 4.03 to 39.99 ng·cm^(–2)·min^(–1) when the SD concentration was increased from 0 to 0.17 mol/L,and increased from 39.99 to 272.62 ng·cm^(–2)·min^(–1) when 0.1 mol/L of PF was used in combination with SD.The pregnant solution in the leaching tests was characterized by X-ray photoelectron spectroscopy and electrospray mass spectrometry,which indicated that Au and(N(CN)2)–in the SD solution formed a series of metal complex ions,[AuNax(N(CN)2)x+2]–(x=1,2,3,or 4). 展开更多
关键词 gold leaching sodium dicyanamide QCM-D leaching kinetics potassium ferrocyanide
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Fermented soy whey induced changes on intestinal microbiota and metabolic influence in mice 被引量:2
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作者 wei han Xuhui Zhuang +3 位作者 Qian Liu Bo Sun Haijiang Miao Xiaolin Zhang 《Food Science and Human Wellness》 SCIE 2022年第1期41-48,共8页
Soy whey(SW)is generated as process waste while preparing soy protein isolates(SPI),and causing severe environmental pollution.Therefore,its value-added utilization is of prime importance for transforming and upgradin... Soy whey(SW)is generated as process waste while preparing soy protein isolates(SPI),and causing severe environmental pollution.Therefore,its value-added utilization is of prime importance for transforming and upgrading traditional industry.This study aims to utilize SW as a substrate for the growth of probiotics and produce a SW based synbiotics.By a series of trials,the effect of the dietary supplementation with this fermented SW(FSW)was analyzed on ICR mice's body weight,metabolites,and intestinal microbiota in 4 weeks.The results showed that,when SW was concentrated 15 times,the count of viable Lactobacillus casei reached 3.4×10^(9) CFU/mL by liquid fermentation method,which was the highest viable cell count among all test strains.In this FSW,the protein,amino acid,total dietary fibre,soluble dietary fibre,and oligosaccharide were 2.10%,1.63%,0.52%,0.51% and 0.79%,respectively.Compared to two control group,the total yields of the short chain fatty acids(SCFAs)were significantly improved(75%-125% at average),while the SCFAs structure was also significantly changed(especially acetic acid and butyrate)in the faeces of mice fed FSW.Meanwhile,FSW dietary addition was associated with the diversity and richness of the intestinal microbiota.Obviously,with mice's body weight loss,Firmicutes/Bacteroides ratio reduced accordingly(<1.21),and the abundance of Akkermansia muciniphila was significantly increased(the maximum amount was about 0.013%).In summary,our results indicated that the dietary supplementation of FSW affected mice's intestinal microbiota and metabolism and improved their health profile. 展开更多
关键词 Soy whey MICROBIOTA Short chain fatty acids Lactobacillus casei Akkermansia muciniphila
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The mechanism study of low-pressure air plasma cleaning on large-aperture optical surface unraveled by experiment and reactive molecular dynamics simulation 被引量:1
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作者 Yuhai LI Qingshun BAI +9 位作者 Yuheng GUAN Hao LIU Peng ZhanG Buerlike BATELIBIEKE Rongqi SHEN Lihua LU Xiaodong YUAN Xinxiang MIAO wei han Caizhen YAO 《Plasma Science and Technology》 SCIE EI CAS CSCD 2022年第6期77-87,共11页
Low-pressure air plasma cleaning is an effective method for removing organic contaminants on large-aperture optical components in situ in the inertial confinement fusion facility.Chemical reactions play a significant ... Low-pressure air plasma cleaning is an effective method for removing organic contaminants on large-aperture optical components in situ in the inertial confinement fusion facility.Chemical reactions play a significant role in plasma cleaning,which is a complex process involving abundant bond cleavage and species generation.In this work,experiments and reactive molecular dynamics simulations were carried out to unravel the reaction mechanism between the benchmark organic contaminants of dibutyl phthalate and air plasma.The optical emission spectroscopy was used to study the overall evolution behaviors of excited molecular species and radical signals from air plasma as a reference to simulations.Detailed reaction pathways were revealed and characterized,and specific intermediate radicals and products were analyzed during experiments and simulation.The reactive species in the air plasma,such as O,HO_(2)and O_(3)radicals,played a crucial role in cleaving organic molecular structures.Together,our findings provide an atomic-level understanding of complex reaction processes of low-pressure air plasma cleaning mechanisms and are essential for its application in industrial plasma cleaning. 展开更多
关键词 organic contaminants large-aperture optical components low-pressure air plasma plasma cleaning reactive species reactive molecular dynamics
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Mechanisms of rotenone-induced neurotoxicity in PC 12 cells 被引量:1
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作者 wei han Lizhong Sun +3 位作者 Jiafeng Chen Ming Chang Hongyan Huo Linsen Hu 《Neural Regeneration Research》 SCIE CAS CSCD 2008年第12期1281-1285,共5页
BACKGROUND: Rotenone-induced neurotoxicity in PC 12 cells has been widely used to study the pathogenesis of Parkinson's disease. However, the precise mechanisms underlying rotenone-induced dopaminergic neuronal dege... BACKGROUND: Rotenone-induced neurotoxicity in PC 12 cells has been widely used to study the pathogenesis of Parkinson's disease. However, the precise mechanisms underlying rotenone-induced dopaminergic neuronal degeneration in Parkinson's disease remains unclear. OBJECTIVE: To establish rotenone-induced neurotoxicity in PC 12 cells, and to investigate the possible action pathways to rotenone-induced neural cell injury at the protein level. DESIGN, TIME AND SETTING: A controlled proteomics study was performed at the Department of Neurology, First Hospital, Jilin University between March 2006 and March 2007. MATERIALS: PC 12 cells were obtained from Shanghai Cell Bank of Chinese Academy of Sciences, China. Rotenone was provided by Sigma, USA. METHODS: PC 12 cells in logarithmic growth phase were treated under experimental and control conditions, respectively. A total of 0.5 μmol/L rotenone, or the same amount of Dulbecco's modified eagle's medium (DMEM), was added in the experimental and control conditions, respectively. MAIN OUTCOME MEASURES: Following 72 hours of rotenone treatment, cellular survival rate was determined by methyl thiazolyl tetrazolium assay, and apoptotic changes were detected by Hoechst 33342 staining. Total cellular protein was extracted to acquire differential protein expression data utilizing two-dimensional differential in-gel electrophoresis. To identify differential protein spots, matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF-MS) was used. RESULTS: In the MTT assay, the experimental condition induced significantly less cell survival compared to the control condition (P 〈 0.01). Hoechst 33342 staining revealed a larger number of apoptotic cells under the experimental condition compared to the control condition (P 〈 0.01), as determined by the presence of nuclear condensation, pyknosis, and nuclear fragmentation. Two-dimensional electrophoresis results showed that the differential expression of protein spots 1069 and 1538 was increased by 144% and 124%, respectively, while that of protein spot 1094 was decreased by 123% in the experimental condition compared to the control condition (P 〈 0.01). By MALDI-TOF-MS analysis and database retrieval, γ-enolase, triosephosphate isomerase 1, and eukaryotic translation initiation factor 4A were confirmed to be involved in rotenone-induced neural cell injury. CONCLUSION: γ-enolase, triosephosphate isomerase 1, and eukaryotic translation initiation factor 4A might participate in rotenone-induced neurotoxicity in PC 12 cells. 展开更多
关键词 PC 12 cells ROTENONE PROTEOMICS cytotoxic effect
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Simple synthesis of novel phosphate electrode materials with unique microstructure and enhanced supercapacitive properties 被引量:1
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作者 Maocheng Liu Jiajia Li +1 位作者 wei han Long Kang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2016年第4期601-608,共8页
Flower-like Ni3P2O8 and flower-like Fe3P2O8 center dot 8H(2)O have been successfully synthesized by a simple chemical precipitation method. X-ray diffraction (XRD) patterns reveal an amorphous phase formation of nicke... Flower-like Ni3P2O8 and flower-like Fe3P2O8 center dot 8H(2)O have been successfully synthesized by a simple chemical precipitation method. X-ray diffraction (XRD) patterns reveal an amorphous phase formation of nickel phosphate (Ni3P2O8) and pure monoclinic phase of Fe3P2O8 center dot 8H(2)O. The novel flower-like Ni3P2O8 and flower-like Fe3P2O8 center dot 8H(2)O when used for supercapacitor electrode materials exhibit a high specific capacitance (C-m) of 1464 F/g and 200 F/g at a current density of 0.5 A/g, respectively. Eventually, an asymmetric supercapacitor is fabricated using Ni3P2O8 as positive electrode and Fe3P2O8 center dot 8H(2)O as negative electrode. A high specific capacitance of 94 F/g is achieved in the high-voltage region of 0 similar to 1.6V, and a large energy density of 32.6 Wh/kg is delivered at power density of 420 W/kg. The findings demonstrate the important and great potential of developing metal phosphate based materials for supercapacitors. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved. 展开更多
关键词 Nickel phosphate Ferrous phosphate Asymmetric supercapacitor PSEUDOCAPACITANCE
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当归多糖促进骨髓移植重建受体小鼠造血功能
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作者 杨婷 廖奎 +6 位作者 黄彩虹 魏晗 王程 杜坤航 汪子铃 王璐 王亚平 《解剖学报》 CAS CSCD 2024年第5期556-564,共9页
目的探讨当归多糖(ASP)调控骨髓基质细胞(BMSCs)促进供体骨髓移植(BMT)重建受体小鼠造血功能的机制。方法分离纯化8~10周龄雄性C57BL/6J小鼠骨髓单个核细胞(BMMNCs),移植给同龄同种雌性受体小鼠,第9天取受体鼠BMMNCs,再次移植给雌性受... 目的探讨当归多糖(ASP)调控骨髓基质细胞(BMSCs)促进供体骨髓移植(BMT)重建受体小鼠造血功能的机制。方法分离纯化8~10周龄雄性C57BL/6J小鼠骨髓单个核细胞(BMMNCs),移植给同龄同种雌性受体小鼠,第9天取受体鼠BMMNCs,再次移植给雌性受体小鼠。移植受体鼠分为对照组:假照射;辐射组:8.0 Gy X射线全身一次性照射;骨髓移植组:照射同辐射组,经尾静脉移植雄性供体BMMNCs(5×10^(6)个细胞);骨髓移植ASP组:同骨髓移植组,从移植的第1天起连续腹腔注射ASP[100 mg/(kg·d)×9]。模型构建期间记录小鼠体重与生存变化,模型构建结束后采集受体小鼠BMMNCs检测Y染色体性别决定区(SRY)基因,测定外周血血常规指标,计算股骨BMMNCs数,观察骨髓组织病理学;分离培养受体鼠BMSCs,观察细胞贴壁生长,5-乙炔基-2’-脱氧尿苷(EdU)法检测BMSCs增殖;分析细胞内活性氧(ROS)水平、超氧化物歧化酶(SOD)活性及丙二醛(MDA)含量;检测BMSCs培养上清液中粒细胞-巨噬细胞集落刺激因子(GM-CSF)、干细胞因子(SCF)和胰岛素样生长因子1(IGF-1)水平,检测BMMNCs与各组BMSCs共培养48 h,形成造血祖细胞混合集落(CFU-Mix)数量;Real-time PCR分析受体BMMNCs的Notch信号通路相关基因(Notch1、Jagged1、Hes1)表达。结果单纯辐射组小鼠全部死亡,骨髓移植ASP组受体鼠体重下降不明显;在受体雌鼠BMMNCs中检测到SRY基因;骨髓移植ASP组受体鼠外周血血常规和BMMNCs总数下降幅度不显著,骨髓组织病理学损伤减轻;ASP能促进BMSCs增殖,降低BMSCs中ROS、MDA含量,提高SOD活性;促进BMSCs分泌SCF、GM-CSF及IGF-1,提高BMMNCs与受体BMSCs共培养后的CFU-Mix产率;提高受体小鼠BMMNCs中Notch1、Jagged1、Hes1 mRNA表达。结论ASP促进受体小鼠造血功能重建机制与减轻造血微环境氧化应激损伤,提高BMSCs分泌造血生长因子,调控Notch信号通路有关。 展开更多
关键词 当归多糖 X射线辐射 骨髓移植 造血重建 骨髓微环境 免疫荧光 实时定量聚合酶链反应 小鼠
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2022—2023年《保健医学研究与实践》外审退稿护理论文特征分析
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作者 戴丽 李佳 +2 位作者 黄文杰 韦晗 胡永国 《保健医学研究与实践》 2024年第3期117-122,共6页
目的探讨2022—2023年《保健医学研究与实践》外审退稿护理论文特征,以期为临床护理人员科研工作提供参考,提高护理类论文质量和稿件录用率。方法本研究选取2022—2023年本刊外审退稿护理论文130篇为研究对象。收集各论文的基本情况,包... 目的探讨2022—2023年《保健医学研究与实践》外审退稿护理论文特征,以期为临床护理人员科研工作提供参考,提高护理类论文质量和稿件录用率。方法本研究选取2022—2023年本刊外审退稿护理论文130篇为研究对象。收集各论文的基本情况,包括第一作者单位所在地区、单位性质[医疗卫生机构(级别、是否为高校附属医院)还是高等学校]、是否有基金项目、第一作者学历、第一作者职称、论文类型、论文合作人数、详细退稿意见。结果第一作者单位所在省份以河南居首,占52.31%。第一作者单位性质以医疗机构为主,占99.23%。基金项目方面以没有基金项目为主,占80.00%。其中,一级医院占1.55%(2/129),二级医院占11.63%(15/129),三级医院占86.82%(112/129);高校附属医院占27.13%(35/129),非附属医院占72.87%(94/129)。第一作者学历以本科为主,占94.61%。第一作者职称以中级为主,占58.46%。论文类型以论著为主,占96.92%。外审退稿论文的退稿原因中占比前3位的依次是缺乏创新性,观察指标选择不恰当或不完整,研究组(干预组均统一命名为研究组)干预方法与对照组雷同或混淆,分别占98.46%、92.31%、84.62%。124篇论著的干预措施主要是针对性护理、预见性护理、集束化护理、延续性护理、人性化护理、多学科协作护理模式、循证护理等,分别占11.29%、6.45%、5.64%、6.44%、4.83%、4.83%、4.03%。120篇论文退稿原因均有观察指标选择不恰当或不完整。归纳具体的退稿原因包括:观察指标和干预措施相互隔离,测评的指标不是干预的内容(92.50%);测评指标意义不大(21.67%);测评指标没有主次(99.17%);测评指标与干预措施因果关系存疑(49.17%);测评指标可行性不强(31.67%);测评指标选择过于简单(19.17%)。结论临床护士的科研素养还有很大的提升空间。尤其需对他们进行选题、观察指标选择、干预方案书写方面的培训。 展开更多
关键词 护理 论文质量 外审退稿 科研素养
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人参皂苷Rg1减轻热应激致小鼠睾丸损伤的机制研究
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作者 黄寅虎 汪子铃 +8 位作者 杜坤航 王程 黄彩虹 杨婷 魏晗 蒋鸿慧 王璐 张庆华 王亚平 《陆军军医大学学报》 CAS CSCD 北大核心 2024年第10期1123-1131,共9页
目的探讨人参皂苷Rg1减轻热应激致小鼠睾丸损伤的机制。方法20只6~8周龄雄性C57BL/6J小鼠按随机数字表法分为4组,每组5只。对照组(Control组)和热应激组(HS组)小鼠腹腔注射0.9%生理盐水[10 mL/(kg·d)×14 d],热应激+人参皂苷Rg... 目的探讨人参皂苷Rg1减轻热应激致小鼠睾丸损伤的机制。方法20只6~8周龄雄性C57BL/6J小鼠按随机数字表法分为4组,每组5只。对照组(Control组)和热应激组(HS组)小鼠腹腔注射0.9%生理盐水[10 mL/(kg·d)×14 d],热应激+人参皂苷Rg1组(HS+Rg1组)和人参皂苷Rg1组(Rg1组)小鼠腹腔注射人参皂苷Rg1[20 mg/(kg·d)×14 d]。HS组与HS+Rg1组小鼠在给药第7天时,将麻醉后小鼠下腹部置于43℃水浴中单次热应激30 min。小鼠精母细胞GC-2spd(ts)分为4组:对照组(Control组)细胞常规培养48 h;热应激组(HS组)细胞常规培养36 h,置于43℃水浴中单次热应激30 min,继续培养12 h;热应激+Rg1组(HS+Rg1组)在细胞培养体系中加入Rg1(终浓度50μmol/L),热应激处理同HS组;Rg1组不给予热应激处理,其余同HS+Rg1组。建模完成后1 d采集眼球血,ELISA法检测血清睾酮水平;摘取睾丸观察形态并称量,计算睾丸指数,HE染色观察睾丸组织病理学形态;制备睾丸组织匀浆检测过氧化氢酶(CAT)、丙二醛(MDA)、超氧化物歧化酶(SOD)水平;取附睾精子,计算机辅助精子分析(CASA)系统分析小鼠精子浓度和活力;TUNEL染色检测GC-2spd(ts)细胞凋亡情况;Western blot检测GC-2spd(ts)细胞Nrf2、Keap1、HO-1、Bax、Bcl-2和Caspase3蛋白表达量;RT-qPCR检测GC-2spd(ts)细胞Nrf2蛋白靶基因GCLC、GCLM和NQO1相对表达量。结果Rg1可阻止热应激所致睾丸质量和睾丸指数下降,减轻睾丸组织结构损伤,阻止精子浓度和活力下降,拮抗热应激所致睾丸间质细胞数量减少和血清睾酮水平下降,降低睾丸组织中MDA累积,提高抗氧化酶CAT和SOD的活性。Rg1还可减轻GC-2spd(ts)细胞凋亡,下调Bax、Caspase3和Keap1蛋白表达,增强Bcl-2、Nrf2和HO-1蛋白表达量,增强Nrf2蛋白靶基因GCLC、GCLM和NQO1相对表达量。结论Rg1对正常小鼠睾丸结构和功能影响不显著,但可有效提高小鼠睾丸抗热应激损伤能力,其机制可能与Rg1激活Nrf2信号通路,提高抗氧化酶活性,减少生精细胞凋亡有关。 展开更多
关键词 人参皂苷RG1 睾丸 热应激 睾酮 氧化应激损伤 机制
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乙炔选择加氢反应中碳化钯的动态精细调控: 气氛和氧化锌助剂的作用
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作者 陈欢 虞周楠 +8 位作者 杨冰 张亚峰 车春霞 刘晓艳 张峰 韩伟 温翯 王爱琴 张涛 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第5期190-200,共11页
碳化钯通常被认为是乙炔选择加氢反应中原位生成的活性相,其生成有助于抑制次表面非选择性的氢化钯物种,从而实现高选择性乙炔加氢制乙烯的目标.次表面上碳化钯和氢化钯物种之间的竞争很大程度上决定了乙炔加氢反应的选择性.然而,由于... 碳化钯通常被认为是乙炔选择加氢反应中原位生成的活性相,其生成有助于抑制次表面非选择性的氢化钯物种,从而实现高选择性乙炔加氢制乙烯的目标.次表面上碳化钯和氢化钯物种之间的竞争很大程度上决定了乙炔加氢反应的选择性.然而,由于实际反应环境的复杂性,反应环境下的两种物种之间的动态转化过程和竞争关系尚不清晰.特别是,反应环境(比如氢气组分)对碳化钯物种的调控机制仍不明确,也使得对碳化钯活性物种的精准调控变得困难.此外,氧化锌助剂作为乙炔选择加氢反应中最常用的助剂之一,存在典型的金属-氧化物界面相互作用,也会对渗碳过程产生重要影响.因此,从动态视角理解碳化钯物种的原位形成过程,对于精准设计和合成高性能乙炔选择加氢钯基催化剂具有重要的科学意义.近年来,先进原位表征光谱技术的不断发展使得从原子、分子层面理解原位过程机制成为可能.本文旨在通过先进的原位表征技术揭示乙炔选择加氢反应中碳化钯物种的动态生成过程,并进一步探究气氛环境、温度、助催化剂等参数对碳化钯物种的动态调控机制,从而为高性能乙炔选择加氢催化剂的精准设计和合成提供有力支撑.原位研究结果表明,在氢气升温还原条件下,空气焙烧后新鲜催化剂中氧化钯相首先转变为氢化钯相;随着还原温度升高,氢化钯相的含氢量逐渐降低.当切换至乙炔选择加氢反应原料气时,氢化钯相迅速分解为金属钯,并随着恒温碳化时间的延长,烃类裂解产生的碳原子逐渐渗入钯的体相,最终形成稳定的碳化钯活性相.通过移除乙炔加氢反应原料气氛中的氢气,考察了反应气中的氢气组分对碳化钯形成的调控机制.实验发现,在仅有乙炔和乙烯存在时,碳化过程仍能发生;而引入少量氢气(体积分数2.2%)后,碳化程度显著增强,C/Pd原子比从0.136提升至0.154.相变机理研究表明,氢气的引入促进了氢化钯物种的形成,并通过晶格扩张作用促进渗碳过程.此外,还研究了氧化锌助剂对原位渗碳过程的影响,揭示了氧化锌助剂对碳化钯的抑制作用.结合原位CO吸附漫反射红外光谱、准原位X射线光电子能谱分析发现,低温氢气还原下Pd-ZnO界面作用促进了微量表面PdZn合金的生成,从而抑制了碳的渗入.这种现象在不含氢气的碳化气氛中尤为显著,碳含量降低一个数量级(C/Pd原子比仅为0.019).在此基础上,通过调节反应条件,实现了对碳化钯物种碳含量的精准调控,并与反应活性关联,揭示了碳化钯含量与乙炔选择加氢反应活性之间的线性关系.电子结构表征和同位素实验进一步表明,Pd-C的电子相互作用促进了向Pd中心原子的电子转移,从而提高了氢气的活化解离能力和乙炔加氢反应活性.综上,本工作原位解析了碳化钯的动态形成过程,阐明了氢气辅助插碳和ZnO抑制插碳的微观机制,实现了碳化钯活性物种的精准调控,揭示了碳化程度与反应活性的线性关系,为高性能乙炔选择加氢催化剂设计提供了参考. 展开更多
关键词 乙炔选择加氢 碳化钯 渗碳过程 原位光谱 动态机制
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仿生集水表面的研究进展及应用
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作者 韦函 梅益 +3 位作者 罗鸿 周学湫 覃冰黎 汪希奎 《表面技术》 EI CAS CSCD 北大核心 2024年第20期19-35,共17页
淡水资源紧缺是当今全球面临的严峻挑战,随着全球人口增长和气候变化的影响,人类面临着日益严重的水资源短缺问题。近年的研究结果显示,通过仿生手段从大气中获取水资源,是一种备受关注的可行方法,仿生集水技术应运而生。仿生集水技术... 淡水资源紧缺是当今全球面临的严峻挑战,随着全球人口增长和气候变化的影响,人类面临着日益严重的水资源短缺问题。近年的研究结果显示,通过仿生手段从大气中获取水资源,是一种备受关注的可行方法,仿生集水技术应运而生。仿生集水技术具有广泛的应用潜力,在大气水收集、海水淡化、工业废水回收和微流控等多个领域具备较好的应用前景。综述了近年来仿生集水技术的发展现状、制备工艺、集水原理和应用前景,总结了基于新型生物学水收集原理的仿生材料/结构/表面处理方法和应用研究现状,分析了仿生集水技术当前面临的问题,包括非均匀润湿集水表面相关理论的深入研究、集水表面耐久性提高及高效低成本制备工艺的开发等,未来的研究方向可集中在提高仿生材料集水性能的可持续性和制备成本的降低等方面,以推动该技术的商业化推广和规模化应用。通过持续的研究和创新,有望看到更多高效、经济的仿生集水技术出现,为人类面临的水资源短缺挑战提供有效的解决方案。 展开更多
关键词 仿生 集水 超疏水 超亲水 水资源 润湿性
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仿生集水纤维研究进展及应用
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作者 罗鸿 梅益 +3 位作者 韦函 周学湫 覃冰黎 汪希奎 《表面技术》 EI CAS CSCD 北大核心 2024年第22期16-34,共19页
淡水资源短缺是全球共同面临的严峻挑战。相关研究发现,模仿蜘蛛丝等生物结构从空气中收集水分,是缓解当前水资源危机的有效途径,已成为仿生集水领域的研究焦点。本文从基础润湿理论、液滴定向传输机理、定向集水机制、仿生纤维设计特... 淡水资源短缺是全球共同面临的严峻挑战。相关研究发现,模仿蜘蛛丝等生物结构从空气中收集水分,是缓解当前水资源危机的有效途径,已成为仿生集水领域的研究焦点。本文从基础润湿理论、液滴定向传输机理、定向集水机制、仿生纤维设计特点及制备方法等方面进行了综述,重点介绍了Young’s方程、Wenzel模型以及Cassie-Baxter模型等基础润湿理论。将纤维集水过程划分为冷凝结露、定向运输和液滴脱附3个阶段,并深入阐述了蜘蛛丝集水过程的内在机制,包括拉普拉斯压力梯度、表面能梯度、滞后效应和液滴悬挂能力。分析了影响集水效率的关键因素,并列举了提升纤维集水效率的常用策略。归纳了仿生纤维结构的主要仿生对象、仿生原理以及所采用的主要制备技术,并对不同技术的优缺点及适用场景进行了详细分析。最后,对不同仿生纤维网状集水器的集水特点和集水效率进行了比较,分析了仿生纤维集水技术在大气水收集、海水淡化、工业蒸气回收以及油水分离等领域的应用潜力,并对该技术的未来发展方向及现有不足提出了改进意见和展望。 展开更多
关键词 仿生纤维 表面润湿 冷凝结露 定向运输 液滴脱附
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适用于降解样本的201个遗传标记检测体系的构建和验证
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作者 韩伟 张庆珍 +1 位作者 杨静 周喆 《遗传》 CAS CSCD 北大核心 2024年第4期306-318,共13页
近年来,法医实践中复杂案件数量逐渐增多,需要联合使用短串联重复序列(short tandem repeat,STR)、单核苷酸多态性(single nucleotide polymorphisms,SNP)、插入缺失多态性(insertion/deletion polymorphism,InDel)、微单倍型(microhapl... 近年来,法医实践中复杂案件数量逐渐增多,需要联合使用短串联重复序列(short tandem repeat,STR)、单核苷酸多态性(single nucleotide polymorphisms,SNP)、插入缺失多态性(insertion/deletion polymorphism,InDel)、微单倍型(microhaplotype,MH)等不同类型的遗传标记,为案件提供更多的参考信息。本研究筛选了24个常染色体STR(autosomes STR,A-STR)、24个Y染色体STR(Y-STR)、110个A-SNP、24个Y-SNP、9个A-InDel、1个Y-InDel、8个MH和Amelogenin共201个遗传标记,建立二代测序检测体系HID_AM Panel v1.0。根据DNA分析方法科学工作组(Scientific Working Group on DNA Analysis Methods,SWGDAM)的验证指南,对该体系的重复性、准确性、灵敏度、对降解样本的适用性、物种特异性、抗抑制性等指标进行评估。本体系分型结果与基于毛细管电泳方法检测的48个STR和Amelogenin结果完全一致,与ForenSeq™ DNA Signature Prep Kit重合的79个SNP分型结果完全一致;当DNA加入量不低于200 pg时可获得全部等位基因分型结果;当检测降解指数大于15.87的模拟降解样本时,检出成功率明显高于GlobalFilerTM PCR扩增试剂盒;当体系内血红素浓度不高于40μmol/L、靛蓝浓度不高于2 mmol/L、或腐殖酸浓度不高于15 ng/μL时,扩增无明显抑制;鸭、鼠、牛、兔、鸡的DNA特异性扩增较少;常规样本中STR检出率达99.74%,SNP、InDel、MH全部检出。综上所述,本研究建立的检测体系具有较高的准确性、灵敏度、物种特异性和抗抑制性,适用于降解样本的个体识别。 展开更多
关键词 二代测序 多类型 遗传标记 降解样本
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Transcriptome-based analysis of key signaling pathways affecting the formation of primordial germ cell in chickens
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作者 Ying Ding Qiong Zhi +3 位作者 Qisheng Zuo Kai Jin wei han Bichun Li 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1644-1657,共14页
Bone morphogenetic protein 4(BMP4)can induce the formation of chicken primordial germ cells(PGCs)in vitro;however,its regulatory mechanism in poultry remains unknown.This study aimed to use RNA-seq to analyze PGCs in ... Bone morphogenetic protein 4(BMP4)can induce the formation of chicken primordial germ cells(PGCs)in vitro;however,its regulatory mechanism in poultry remains unknown.This study aimed to use RNA-seq to analyze PGCs in chicken embryos and iPGCs induced by BMP4 in vitro,clarify the internal regulatory factors of PGCs,analyze the mechanism of the formation of PGCs,and lay a theoretical foundation for the further optimization of PGCs induction systems.Embryonic stem cells(ESCs),PGCs and iPGCs induced by BMP4 in vitro were collected.The transcriptional maps of the three cell types were studied using RNA-seq.The results showed 6,142 genes differentially expressed between PGCs and iPGCs,of which 2,728 were upregulated in iPGCs and 3,414 were downregulated in iPGCs.Compared to that in ESCs,BMP4 was significantly upregulated in PGCs and iPGCs.KEGG results showed that both the TGF-βand Wnt signaling pathways were activated during the formation of PGCs in vitro and in vivo,and the activation was more significant during iPGCs induced by BMP4.The expression of Nodal,an inhibitory factor of TGF-βsignaling,was significantly decreased in PGCs and iPGCs,but was not expressed in iPGCs,which further supports our conclusion.Additionally,the Lysosome and PI3K-AKT signaling pathways were significantly enriched in PGCs and iPGCs,respectively.Further,transmission electron microscopy(TEM)results showed that the number of autolysosomes was significantly higher after the addition of BMP4,which is consistent with the KEGG results.Furthermore,the number of PGCs was significantly reduced after ATG14 was interfered in vivo and in vitro.In conclusion,this study screened out the key signaling pathways during the formation of PGCs,aiming to provide help for enriching the mechanism network regulating PGCs formation in chicken and laying a theoretical foundation for further improving the efficiency of inducing PGCs in vitro. 展开更多
关键词 RNA-seq BMP4 PGCS ATG14 CHICKEN
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Effect of chemical regulators on the recovery of leaf physiology,dry matter accumulation and translocation,and yield-related characteristics in winter wheat following dry-hot wind
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作者 Yanan Xu Yue Wu +5 位作者 Yan han Jiqing Song Wenying Zhang wei han Binhui Liu Wenbo Bai 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期108-121,共14页
Dry-hot wind stress causes losses in wheat productivity in major growing regions worldwide,especially winter wheat in the Huang-Huai-Hai Plain of China,and both the occurrence and severity of such events are likely to... Dry-hot wind stress causes losses in wheat productivity in major growing regions worldwide,especially winter wheat in the Huang-Huai-Hai Plain of China,and both the occurrence and severity of such events are likely to increase with global climate change.To investigate the recovery of physiological functions and yield formation using a new noncommercial chemical regulator(NCR)following dry-hot wind stress,we conducted a three-year field experiment(2018-2021)with sprayed treatments of tap water(control),monopotassium phosphate(CKP),NCR at both the jointing and flowering stages(CFS),and NCR only at the jointing stage(FSJ)or flowering stage(FSF).The leaf physiology,biomass accumulation and translocation,grain-filling process,and yield components in winter wheat were assessed.Among the single spraying treatments,the FSJ treatment was beneficial for the accumulation of dry matter before anthesis,as well as larger increases in the maximum grain-filling rate and mean grain-filling rate.The FSF treatment performed better in maintaining a high relative chlorophyll content as indicated by the SPAD value,and a low rate of excised leaf water loss in flag leaves,promoting dry matter accumulation and the contribution to grain after anthesis,prolonging the duration of grain filling,and causing the period until the maximum grain-filling rate reached earlier.The CFS treatment was better than any other treatments in relieving the effects of dry-hot wind.The exogenous NCR treatments significantly increased grain yields by 12.45-18.20% in 2018-2019,8.89-13.82% in 2019-2020,and 8.10-9.00% in 2020-2021.The conventional measure of the CKP treatment only increased grain yield by 6.69% in 2020-2021.The CFS treatment had the greatest mitigating effect on yield loss under dry-hot wind stress,followed by the FSF and FSJ treatments,and the CKP treatment only had a minimal effect.In summary,the CFS treatment could be used as the main chemical control measure for wheat stress resistance and yield stability in areas with a high incidence of dry-hot wind.This treatment can effectively regulate green retention and the water status of leaves,promote dry matter accumulation and efficient translocation,improve the grain-filling process,and ultimately reduce yield losses. 展开更多
关键词 preparation stress foliar spraying GRAIN-FILLING REMOBILIZATION
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Textured Perovskite/Silicon Tandem Solar Cells Achieving Over 30% Efficiency Promoted by 4-Fluorobenzylamine Hydroiodide
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作者 Jingjing Liu Biao Shi +14 位作者 Qiaojing Xu Yucheng Li Yuxiang Li Pengfei Liu Zetong SunLi Xuejiao Wang Cong Sun wei han Diannan Li Sanlong Wang Dekun Zhang Guangwu Li Xiaona Du Ying Zhao Xiaodan Zhang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期557-570,共14页
Monolithic textured perovskite/silicon tandem solar cells(TSCs)are expected to achieve maximum light capture at the lowest cost,potentially exhibiting the best power conversion efficiency.However,it is challenging to ... Monolithic textured perovskite/silicon tandem solar cells(TSCs)are expected to achieve maximum light capture at the lowest cost,potentially exhibiting the best power conversion efficiency.However,it is challenging to fabricate high-quality perovskite films and preferred crystal orientation on commercially textured silicon substrates with micrometersize pyramids.Here,we introduced a bulky organic molecule(4-fluorobenzylamine hydroiodide(F-PMAI))as a perovskite additive.It is found that F-PMAI can retard the crystallization process of perovskite film through hydrogen bond interaction between F^(−)and FA^(+)and reduce(111)facet surface energy due to enhanced adsorption energy of F-PMAI on the(111)facet.Besides,the bulky molecular is extruded to the bottom and top of perovskite film after crystal growth,which can passivate interface defects through strong interaction between F-PMA+and undercoordinated Pb^(2+)/I^(−).As a result,the additive facilitates the formation of large perovskite grains and(111)preferred orientation with a reduced trap-state density,thereby promoting charge carrier transportation,and enhancing device performance and stability.The perovskite/silicon TSCs achieved a champion efficiency of 30.05%based on a silicon thin film tunneling junction.In addition,the devices exhibit excellent longterm thermal and light stability without encapsulation.This work provides an effective strategy for achieving efficient and stable TSCs. 展开更多
关键词 Perovskite crystallization (111)preferred orientation Defect passivation Perovskite/silicon tandem solar cells
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碱提茶渣蛋白乳化性及其乳化稳定性的研究
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作者 张圣煜 魏汉 +2 位作者 周芯雨 王梦田 张晨 《食品工业科技》 CAS 北大核心 2024年第23期50-58,共9页
碱提茶渣蛋白质(Alkali-extracted tea residue protein,ATRP)作为新型蛋白资源,具有成为食品级乳化剂的潜力。本研究以ATRP为原料,测定其形成的乳液类型及亲水疏水平衡值,分析室温条件下(20℃)不同乳化因素(油水比、乳化剂浓度、pH、... 碱提茶渣蛋白质(Alkali-extracted tea residue protein,ATRP)作为新型蛋白资源,具有成为食品级乳化剂的潜力。本研究以ATRP为原料,测定其形成的乳液类型及亲水疏水平衡值,分析室温条件下(20℃)不同乳化因素(油水比、乳化剂浓度、pH、存储温度)对其乳化性(静置10 min)及乳化稳定性(静置15 d)的影响,并在优化条件下将ATRP、大豆分离蛋白和乳清蛋白的乳化性和乳化稳定性进行对比分析。结果表明,ATRP乳液为水包油(O/W)类型,其亲水疏水平衡值为13。在油水比7:3、浓度4 mg/mL、pH7和储藏温度为20℃的条件下,ATRP乳化能力较好。在该条件下,ATRP乳液静置10 min时,乳化活性指数(EAI值)为43.3 m^(2)/g,乳化指数(CI值)为97%。静置15 d后,ATRP乳液的EAI值和CI值保留了82.9%和88.5%,显示出较强的稳定性。相比于大豆分离蛋白和乳清蛋白,ATRP乳液在储藏15 d的过程中其粒径变化较小,且其在储存过程中的ζ-电位约为大豆分离蛋白的2倍、乳清蛋白的2.5倍,显示出更好的乳化性。 展开更多
关键词 茶渣 蛋白质 乳化性 乳清蛋白 大豆分离蛋白
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