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Er-Yb玻璃低应力减反射膜的研制
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作者 潘永刚 袁浩春 +6 位作者 林兆文 曾彬 张功 石澎 王龙 郗梓成 付秀华 《红外与激光工程》 北大核心 2026年第1期376-385,共10页
随着激光技术的快速发展,Er-Yb玻璃在人眼安全激光器中得到广泛应用,但Er-Yb玻璃作为激光器谐振腔的基底时,表面膜层附着力差、应力大的问题降低了激光器的输出效率。采用Ta_(2)O_(5)和SiO_(2)作为高低折射率材料,利用离子辅助沉积技术,... 随着激光技术的快速发展,Er-Yb玻璃在人眼安全激光器中得到广泛应用,但Er-Yb玻璃作为激光器谐振腔的基底时,表面膜层附着力差、应力大的问题降低了激光器的输出效率。采用Ta_(2)O_(5)和SiO_(2)作为高低折射率材料,利用离子辅助沉积技术,在Er-Yb玻璃基底上研制了低应力的减反射膜。通过使用COMSOL软件建立热仿真模型,引入SiO_(2)粘接层,降低膜层热应力,解决了膜层脱膜的问题;通过设计梯度工艺参数,建立了残余应力与离子源能量和膜层厚度的数学模型,选取合适的工艺参数,制备了低应力减反射膜,在(1 535±3) nm波长平均反射率为0.069%,膜层残余应力为-8.61 MPa,并且通过了附着力、水煮及湿热试验,满足使用要求。 展开更多
关键词 减反射膜 er-Yb玻璃 离子辅助沉积 附着力 低应力
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Chitinase boosts endoplasmic reticulum stress and triggers apoptosis and autophagy in a hepatocellular carcinoma rat model
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作者 Asmaa I.Nabeel Fatma S.M.Moawed Enas M.Moustafa 《Asian Pacific Journal of Tropical Biomedicine》 2026年第3期129-138,共10页
Objective:To assess the antitumor activity of the novel chitinase produced by fermented,isolated Trichoderma viride in a hepatocellular carcinoma(HCC)male rat model.Methods:Diethyl-nitrosamine induction combined with ... Objective:To assess the antitumor activity of the novel chitinase produced by fermented,isolated Trichoderma viride in a hepatocellular carcinoma(HCC)male rat model.Methods:Diethyl-nitrosamine induction combined with ionizing radiation exposure was used to establish the HCC rat model.All rats were divided into 4 groups:the control group,the chitinase group,the HCC group,and the HCC+chitinase group.The antiproliferative effect of chitinase was evaluated in human HCC cells.The effect of chitinase in vivo on oxidative stress,endoplasmic reticulum stress chaperones,autophagy markers,PI3K/AKT/mTOR,AMPK pathway expression,and apoptotic indicators was determined and confirmed by histological examination.Results:Chitinase significantly inhibited the viabilities of HepG2 cells.Moreover,in the Wistar male rat model of HCC,chitinase decreased ATP levels,modulated endoplasmic reticulum stress,mediated autophagy factors,and promoted apoptosis.Conclusions:Chitinase might play a role in the apoptosis as well as autophagy pathways and may act as a potential tumor suppressor. 展开更多
关键词 Trichoderma viride CHITINASE Hepatocellular carcinoma er stress APOPTOSIS AUTOPHAGY PI3K/AKT/MTOR AMPK
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Generation and dynamics of special mode-locked pulses in an ultrafast Er-doped fiber laser with SMF-GIMF-SMF saturable absorber 被引量:1
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作者 LIN Yingjie ZENG Qiong +3 位作者 JI Yubo SONG Yufeng WANG Ke WANG Zhenhong 《Optoelectronics Letters》 2025年第5期265-270,共6页
In this paper, we have demonstrated an Er-doped ultrafast laser with a single mode fiber-gradient index multimode fiber-single mode fiber(SMF-GIMF-SMF, SMS) structure as saturable absorber(SA), which can generate not ... In this paper, we have demonstrated an Er-doped ultrafast laser with a single mode fiber-gradient index multimode fiber-single mode fiber(SMF-GIMF-SMF, SMS) structure as saturable absorber(SA), which can generate not only stable single-pulse state, but also special mode-locked pulses with the characteristics of high energy and noisy behaviors at proper pump power and cavity polarization state. In addition, we have deeply investigated the real-time spectral evolutions of the mode-locked pulses through the dispersive Fourier transformation(DFT) technique. It can be found that the pulse regime can actually consist of a lot of small noise pulses with randomly varying intensities. We believe that these results will further enrich the nonlinear dynamical processes in the ultrafast lasers. 展开更多
关键词 ultrafast laser er doped fiber SMF GIMF SMF dispersive Fourier transformation saturable absorber sa mode locked pulses nonlinear dynamics saturable absorber
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Er和Cu复合添加对A356合金组织与力学性能的影响
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作者 汤江涛 冯丽 +3 位作者 冯恩浪 姜岳峰 梁田 马颖澈 《金属热处理》 北大核心 2026年第1期12-21,共10页
通过在A356铝合金中加入0.2%、0.4%稀土元素Er及复合添加0.1%Er、1.76%Cu,研究了Er、Cu对压铸成形A356铝合金微观组织和力学性能的影响。结果表明:加入稀土元素Er后,共晶Si的形貌由长纤维状或长棒状转变为细小的纤维状或点状结构,共晶S... 通过在A356铝合金中加入0.2%、0.4%稀土元素Er及复合添加0.1%Er、1.76%Cu,研究了Er、Cu对压铸成形A356铝合金微观组织和力学性能的影响。结果表明:加入稀土元素Er后,共晶Si的形貌由长纤维状或长棒状转变为细小的纤维状或点状结构,共晶Si的共晶转变温度及α-Al的熔化温度降低。随着Er含量的增加,合金的抗拉强度由242.0 MPa小幅升高至250.0 MPa,但伸长率由7.00%降低至5.50%。在A356铝合金中复合添加0.1%Er和1.76%Cu时,合金中形成了Al_(3)Er、Al_(8)Cu_(4)Er、Al_(2)Cu等金属间化合物,合金的抗拉强度为243.0 MPa,伸长率降低为1.50%,表明Er和Cu未表现出良好的协同强韧化作用。其主要原因是快速凝固促使富Cu相以粗大块状或团簇状在枝晶间析出,导致应力集中,并在拉伸过程中于其棱角处萌生微裂纹,从而严重恶化塑性。 展开更多
关键词 压铸态 A356合金 稀土er CU 复合协同
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锻造工艺及热处理对含Er7050铝合金组织与力学性能的影响
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作者 刘宇航 荣莉 +8 位作者 黄晖 陈炯燊 马晨曦 史晓成 魏午 文胜平 高坤元 吴晓蓝 聂祚仁 《稀有金属材料与工程》 北大核心 2026年第2期517-527,共11页
为了探究多向锻造对铝合金微观组织及力学性能的影响,以均火态含Er7050铝合金为研究对象,对该合金在400℃下进行了3种不同锻造道次的多向锻造,即三墩三拔(3U3CS)、六墩六拔(6U6CS)以及九墩九拔(9U9CS)。随后,合金经过固溶处理、水淬和T... 为了探究多向锻造对铝合金微观组织及力学性能的影响,以均火态含Er7050铝合金为研究对象,对该合金在400℃下进行了3种不同锻造道次的多向锻造,即三墩三拔(3U3CS)、六墩六拔(6U6CS)以及九墩九拔(9U9CS)。随后,合金经过固溶处理、水淬和T6时效处理。对样品进行微观结构分析和机械性能测试。通过比较3种不同锻造工艺所得样品的机械性能,发现经过九墩九拔锻造工艺处理的样品具有最佳的机械性能,这归功于该锻造工艺使其产生细小的晶粒和致密的析出强化相,该锻造工艺条件下样品的平均抗拉强度为621.4 MPa,平均屈服强度为545.4 MPa,平均伸长率为13.58%,对比其他两种锻造工艺处理的样品均有提升,这表明优化的锻造工艺显著改善了机械性能。 展开更多
关键词 er7050铝合金 多向锻造 显微组织演变 再结晶
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党参-茯苓配伍调控ERα/PI3K/Akt信号通路改善单侧颈总动脉永久结扎痴呆大鼠的认知障碍
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作者 杨佳瑶 何玉莲 +5 位作者 郭延垒 尚芳红 花雷 阳勇 张小梅 魏江平 《南方医科大学学报》 北大核心 2026年第2期247-258,共12页
目的基于UPLC-Q-TOF-MS/MS分析研究党参-茯苓配伍(CRP)治疗痴呆症的作用机制。方法采用于UPLC-Q-TOFMS/MS分析单侧颈总动脉永久结扎(UCCA)模型大鼠的CRP的入血入脑成分,并对入血和入脑成分进行网络药理学分析。CRP灌胃UCCA大鼠干预1个... 目的基于UPLC-Q-TOF-MS/MS分析研究党参-茯苓配伍(CRP)治疗痴呆症的作用机制。方法采用于UPLC-Q-TOFMS/MS分析单侧颈总动脉永久结扎(UCCA)模型大鼠的CRP的入血入脑成分,并对入血和入脑成分进行网络药理学分析。CRP灌胃UCCA大鼠干预1个月后通过Morris水迷宫评价其学习记忆能力;苏木精-伊红染色观察海马和皮质的病理形态学变化;NeuN染色分析海马和皮层神经元数量变化;采用代谢组学分析CRP治疗UCCA大鼠前后脑内代谢物变化差异;酶联免疫吸附测定(ELISA)检测脑内谷氨酸和γ-氨基丁酸(GABA)的含量;免疫组化法考察雌激素受体α(ERα)的蛋白表达;Western blotting分析p-PI3K、PI3K、p-Akt、Akt的蛋白表达。结果在UCCA大鼠的脑组织和血液中分别鉴定出125种和126种成分,其中,脑组织中发现了89种党参成分和36种茯苓成分,血液中发现了85种党参成分和41种茯苓成分。网络药理学分析表明,CRP治疗痴呆主要与调节进入脑组织的成分所影响的PI3K/Akt等信号通路有关。与假手术组比较,模型大鼠的第5天的逃避潜伏期明显延长(P<0.01),平台象限活动时间、海马和皮质的神经元明显损伤且NeuN平均光密度明显下降(P<0.05);脑内谷氨酸和GABA/谷氨酸含量明显升高(P<0.05),ERα、p-PI3K/PI3K、p-Akt/Akt蛋白表达下调(P<0.05)。与模型组比较,CRP干预大鼠的第5天的逃避潜伏期明显缩短(P<0.01),穿越平台次数、平台象限活动时间均明显增加(P<0.05),海马和皮质的神经元损伤好转且NeuN平均光密度明显升高(P<0.05);代谢组学分析表明CRP治疗作用主要富集于雌激素信号通路和GABA能突触等信号通路。CRP组大鼠脑内的谷氨酸和GABA/谷氨酸含量明显降低(P<0.05),ERα、p-PI3K/PI3K和p-Akt/Akt蛋白表达上调(P<0.05)。结论CRP能够改善UCCA痴呆大鼠的学习和记忆缺陷,这与其对脑内ERα/PI3K/Akt信号通路的调节有关。 展开更多
关键词 党参-茯苓配伍 痴呆 单侧颈总动脉永久结扎大鼠 γ-氨基丁酸 erα/PI3K/Akt信号通路
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Up-conversion photoluminescence and thermoluminescence studies of Er^(3+)doped Y_(2)O_(3)phosphors
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作者 Dhaleshwari Fekar Prachi P.Nimje +1 位作者 Ravi SHRIVASTAVA Siteshwari Chandrakar 《Optoelectronics Letters》 2025年第11期667-670,共4页
This paper reports the preparation of yttrium oxide(Y_(2)O_(3))doped with various concentrations of Er^(3+)using high temperature synthesis method.Photoluminescence(PL)emission spectra of the samples were recorded at ... This paper reports the preparation of yttrium oxide(Y_(2)O_(3))doped with various concentrations of Er^(3+)using high temperature synthesis method.Photoluminescence(PL)emission spectra of the samples were recorded at an excitation of 980 nm laser source.Two prominent peaks centered at 484 nm and 574 nm were found and attributed to the^(2)P3/2→^(4)I_(11/2)and^(4)S_(3/2)→^(4)I_(15/2),respectively.The sample with 2.5 mol%of Er^(3+)provided the optimum intensity in emission spectra.The sample with optimum PL emission was investigated for its thermoluminescence(TL)glow curve exhibited the second order kinetics.The peak TL intensity was found around 236°C,i.e.,towards high temperature which supports the fact of formation of deeper traps.Therefore,the material taken may be regarded as a good candidate for light emitting diode(LED)applications. 展开更多
关键词 er emission spectrathe high temperature synthesis THerMOLUMINESCENCE PHOSPHORS high temperature synthesis methodphotoluminescence pl emission Y O up conversion
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Er:YAG激光在糖尿病肾病并发牙周炎中的应用及对牙周状态、肾功能、龈沟液炎症因子的影响
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作者 么远 曹佳佳 +4 位作者 殷悦 赵志宇 毕磊 卢娜 张春光 《检验医学与临床》 2026年第1期101-105,111,共6页
目的探讨Er:YAG激光在糖尿病肾病并发牙周炎中的应用及对牙周状态、肾功能、龈沟液炎症因子的影响。方法选取2021年4月至2024年11月该院收治的124例糖尿病肾病并发牙周炎患者作为研究对象,按照治疗方法将所有患者分为基础组和激光组,每... 目的探讨Er:YAG激光在糖尿病肾病并发牙周炎中的应用及对牙周状态、肾功能、龈沟液炎症因子的影响。方法选取2021年4月至2024年11月该院收治的124例糖尿病肾病并发牙周炎患者作为研究对象,按照治疗方法将所有患者分为基础组和激光组,每组62例。基础组给予牙周基础治疗,激光组在基础组治疗的基础上给予Er:YAG激光治疗。比较基础组和激光组患者的临床疗效、牙周状态相关指标[探诊深度(PD)、改良龈沟出血指数(mSBI)、牙齿松动度(TM)、临床附着丧失(CAL)]、肾功能和血糖指标[尿素氮(BUN)、血肌酐(SCr)、糖化血红蛋白(HbA1c)]、龈沟液炎症因子[肿瘤坏死因子(TNF)-α、基质金属蛋白酶(MMP)-8、细胞间黏附分子(ICAM)-1]。结果激光组治疗总有效率高于基础组,差异有统计学意义(P<0.05)。基础组和激光组治疗后PD、mSBI、TM、CAL均小于治疗前,SCr、BUN、HbA1c、TNF-α、MMP-8、ICAM-1水平均低于治疗前,且激光组治疗后PD、mSBI、TM、CAL均小于基础组,TNF-α、MMP-8、ICAM-1水平均低于基础组,差异均有统计学意义(P<0.05)。结论Er:YAG激光联合牙周基础治疗糖尿病肾病并发牙周炎有助于改善牙龈症状,降低炎症反应,促进患者康复。 展开更多
关键词 er:YAG激光治疗 牙周基础治疗 糖尿病肾病 牙周炎 炎症反应
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Nd:YAG激光和Er:YAG激光治疗2型糖尿病患者种植体周围炎的短期效果评价
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作者 孙斌 王苹 《上海口腔医学》 2026年第1期54-59,共6页
目的:评价Nd:YAG激光和Er:YAG激光治疗2型糖尿病患者种植体周围炎的短期效果。方法:选择2021年2月—2024年2月收治的2型糖尿病种植体周围炎患者97例,采用随机数字表法分为A组(48例,Nd:YAG激光)和B组(49例,Er:YAG激光)。对比两组患者治... 目的:评价Nd:YAG激光和Er:YAG激光治疗2型糖尿病患者种植体周围炎的短期效果。方法:选择2021年2月—2024年2月收治的2型糖尿病种植体周围炎患者97例,采用随机数字表法分为A组(48例,Nd:YAG激光)和B组(49例,Er:YAG激光)。对比两组患者治疗前后的牙周指标、炎性因子水平、骨吸收程度、龈沟液细菌含量、血糖水平、生活质量评分及疗效。结果:治疗后,两组龈沟出血指数(sulcus bleeding index,SBI)、菌斑指数(plaque index,PLI)和牙周探诊深度(probing depth,PD)显著降低,且A组SBI、PLI和PD均显著低于B组(P<0.05)。治疗后,两组近、远中边缘骨吸收显著降低,且A组显著低于B组(P<0.05)。两组炎性因子水平治疗后显著降低,A组白细胞介素6(IL-6)、肿瘤坏死因子α(tumor necrosis factorα,TNF-α)和基质金属蛋白酶8(matrix metalloproteinase-8,MMP-8)水平均显著低于B组(P<0.05)。两组龈沟液细菌含量治疗后显著降低,且A组显著低于B组(P<0.05)。治疗前、后两组患者血糖水平相比无显著差异(P>0.05)。治疗后,两组生活质量评分显著升高,A组躯体功能、心理功能及总分均显著高于B组(P<0.05)。两组治疗总有效率相比,无显著差异(P>0.05)。结论:Nd:YAG激光治疗2型糖尿病患者种植体周围炎能有效改善牙周情况,减少骨吸收,降低炎性因子水平及龈沟液细菌含量,提高生活质量。 展开更多
关键词 ND:YAG激光 er:YAG激光 2型糖尿病 种植体周围炎 牙周指标
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简谈Buffer区域漫延机制对CBTC列车运行影响
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作者 施宇锋 《铁路通信信号工程技术》 2026年第2期103-108,共6页
基于列车定位与安全防护包络计算原理,重点分析基于通信的列车控制(CBTC)系统中列车安全防护缓冲(Buffer)区域的生成与漫延机制。通过构建不同运营场景,系统研究前车丢失定位或车载ATP故障时,Buffer区域漫延对后续CBTC列车运行的影响规... 基于列车定位与安全防护包络计算原理,重点分析基于通信的列车控制(CBTC)系统中列车安全防护缓冲(Buffer)区域的生成与漫延机制。通过构建不同运营场景,系统研究前车丢失定位或车载ATP故障时,Buffer区域漫延对后续CBTC列车运行的影响规律。结果表明,Buffer区域漫延会导致后车移动授权受限甚至触发紧急制动,进而降低线路通过能力。为此,提出合理增加计轴点布局、优化列车追踪间隔等应对措施,可为实际运营中故障情况下的行车组织与效率提升提供参考。 展开更多
关键词 安全防护包络 CBTC BUFFer 漫延机制
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乳腺癌组织ZMYND10表达及其与ER、PR、HER-2的关系
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作者 叶敏 张锦丰 +3 位作者 吴静娜 朱文标 杨日辉 范苑林 《中南医学科学杂志》 2025年第6期1061-1064,共4页
目的探究ZMYND10在乳腺癌组织中的表达水平及其与雌激素受体(ER)、孕激素受体(PR)和人表皮生长因子受体-2(HER-2)表达的关系。方法选择乳腺癌患者148例,收集临床资料及肿瘤组织标本。采用免疫组织化学法检测ZMYND10在乳腺癌组织及癌旁... 目的探究ZMYND10在乳腺癌组织中的表达水平及其与雌激素受体(ER)、孕激素受体(PR)和人表皮生长因子受体-2(HER-2)表达的关系。方法选择乳腺癌患者148例,收集临床资料及肿瘤组织标本。采用免疫组织化学法检测ZMYND10在乳腺癌组织及癌旁正常组织中的表达,根据ZMYND10表达水平将患者分为高表达组与低表达组,并检测两组ER、PR和HER-2表达情况,采用多因素Logistic回归分析ZMYND10表达与临床资料及各指标的关系。结果ZMYND10在乳腺癌组织中的阳性表达率低于癌旁正常组织(P<0.05)。高表达组中年龄<50岁及淋巴转移<4个者比例高于低表达组(P<0.05)。高表达组中PR阳性者比例高于低表达组(P<0.05)。回归分析显示,年龄<50岁及PR阳性均为ZMYND10高表达的影响因素(P<0.05)。结论ZMYND10在乳腺癌组织中低表达,其高表达与年龄<50岁及PR阳性有密切关系。 展开更多
关键词 乳腺癌 ZMYND10 er PR Her-2
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SS18阳性滑膜肉瘤中ER/PR阳性亚型的临床病理特征及意义
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作者 陈少华 吴春林 +2 位作者 曲利娟 郑智勇 曾德华 《中国组织化学与细胞化学杂志》 2025年第5期478-484,共7页
目的观察ER、PR、PAX8、PAX2及WT-1在滑膜肉瘤中的表达,筛选出其中的ER/PR阳性亚型,分析ER/PR表达与临床病理特征及其预后的关系,探讨ER/PR阳性亚型滑膜肉瘤的起源。方法对82例经形态学及免疫表型诊断为滑膜肉瘤的组织微阵列行SS18 FIS... 目的观察ER、PR、PAX8、PAX2及WT-1在滑膜肉瘤中的表达,筛选出其中的ER/PR阳性亚型,分析ER/PR表达与临床病理特征及其预后的关系,探讨ER/PR阳性亚型滑膜肉瘤的起源。方法对82例经形态学及免疫表型诊断为滑膜肉瘤的组织微阵列行SS18 FISH检测,并行免疫组化检测ER、PR、PAX8、PAX2及WT-1的表达。结果SS18阳性滑膜肉瘤有38例,ER/PR阳性阈值?5%时,ER/PR阳性率为28.9%(11/38),ER/PR阳性多见于年龄<45岁(10/11)、组织学分级Ⅱ级(11/11),且无进展生存率较高(10/11)。ER/PR阳性阈值≥1%时,ER/PR阳性率为44.7%(17/38),ER/PR阳性仅与组织学分级相关。38例滑膜肉瘤PAX2及WT-1表达均阴性,仅2例ER/PR阴性滑膜肉瘤表达PAX8(5.3%)。结论ER/PR阳性亚型滑膜肉瘤的ER/PR阳性阈值≥5%较为合适。ER/PR阳性亚型滑膜肉瘤患者预后明显较好,提示ER、PR是滑膜肉瘤的一项重要预后指标,有可能成为滑膜肉瘤患者内分泌治疗的重要依据。ER/PR阳性亚型滑膜肉瘤起源与müllerian未观察到相关性。 展开更多
关键词 滑膜肉瘤 er/PR阳性亚型 müllerian 荧光原位杂交 免疫组化
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ERα及ERβ基因多态性与骨质疏松症相关性研究进展 被引量:1
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作者 李宁 黄秀峰 +3 位作者 屈国栋 叶广彬 王长丽 宾晓芸 《中国骨质疏松杂志》 北大核心 2025年第4期564-569,共6页
骨质疏松症是以骨量减少及骨微结构破坏为特征的复杂多基因疾病,易受基因层面调控的影响,多个基因突变遗传相互作用使其具有很强的遗传性,骨质疏松症成为当今老龄化社会的主要负担。越来越多的研究表明雌激素受体基因多态性和骨质疏松... 骨质疏松症是以骨量减少及骨微结构破坏为特征的复杂多基因疾病,易受基因层面调控的影响,多个基因突变遗传相互作用使其具有很强的遗传性,骨质疏松症成为当今老龄化社会的主要负担。越来越多的研究表明雌激素受体基因多态性和骨质疏松症的关系密切。ERα及ERβ是雌激素受体的两种主要亚型,主要在细胞核中起作用,通过与相关的DNA调控序列结合来调节特定靶基因的转录,且可以通过其介导的机制直接刺激成骨细胞及破骨细胞,从而引发骨密度下降,导致骨质疏松症的发生。为进一步探究雌激素受体基因多态性与发生骨质疏松症的风险,笔者从ERα:PvuII、XbaI、G2014A和ERβ:AluI、RsaI的5个位点基因多态性与骨质疏松症相关性进行综述,以推测骨质疏松症预防和治疗方面可能的发展。 展开更多
关键词 骨质疏松症 erΑ erΒ 基因多态性
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Sb^(3+)/Er^(3+)共掺杂Cs_(2)NaGdCl_(6)双钙钛矿中能量传递机制与可调谐发光
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作者 班季峰 李忠辉 +4 位作者 张兴隆 刘长立 赵星胜 周恒为 蒋小康 《物理学报》 北大核心 2026年第3期359-367,共9页
开发高效、稳定且发光颜色可调的无铅钙钛矿荧光粉是推动其在新一代发光器件中应用的核心挑战.本研究采用微波固相法成功合成了一系列不同浓度的Er^(3+)掺杂Cs_(2)NaGd_(0.985)Cl_(6):0.015Sb^(3+)荧光粉.X射线衍射结果表明,Er^(3+)的... 开发高效、稳定且发光颜色可调的无铅钙钛矿荧光粉是推动其在新一代发光器件中应用的核心挑战.本研究采用微波固相法成功合成了一系列不同浓度的Er^(3+)掺杂Cs_(2)NaGd_(0.985)Cl_(6):0.015Sb^(3+)荧光粉.X射线衍射结果表明,Er^(3+)的引入未引起晶体结构变化或产生杂质相.在336 nm紫外光激发下,该材料同时展现出源于基质自陷态激子(STE)的460 nm宽带蓝光发射和Er^(3+)离子的特征绿光/红光发射(524 nm,550 nm,667 nm).通过研究浓度依赖的发光行为,发现最优Er^(3+)掺杂浓度为0.03,此时发光强度最大,量子效率达到37.09%;其浓度猝灭机制被证实为电偶极-电偶极相互作用.在该优化浓度下,证实了从基质STE到Er^(3+)离子之间存在有效的能量传递通道,能量传递效率为24.58%.此外,优化样品Cs_(2)NaGd_(0.955)Cl_(6):0.015Sb^(3+),0.03Er^(3+)表现出良好的热稳定性,在423 K高温下的发光强度仍能维持室温(298 K)下的69.4%.更为重要的是,通过调节Er^(3+)掺杂浓度,成功实现了发光颜色从蓝光(CIE:0.160,0.194)到绿光(CIE:0.215,0.374)的可调谐.本研究不仅阐明了Sb^(3+)/Er^(3+)共掺杂双钙钛矿中的能量传递机制,而且所制备的高稳定性、颜色可调的荧光粉展现出在绿光发光二极管中的应用潜力. 展开更多
关键词 双钙钛矿 锑/铒共掺杂 能量传递 颜色可调
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ERŌS IN XENOPHON’S POLITICAL AND ETHICAL THOUGHT
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作者 Ivan Jordović 《Journal of Ancient Civilizations》 2025年第1期25-76,113,114,共54页
This article attempts to trace the status and many manifestations of erōs in Xenophon’s ethical and political thought.It examines its meaning in the narrow sense of“love and desire”and the broad sense of“affectiv... This article attempts to trace the status and many manifestations of erōs in Xenophon’s ethical and political thought.It examines its meaning in the narrow sense of“love and desire”and the broad sense of“affective feelings and friendship in the life of the family and the polis.”The principal goal is to demonstrate the remarkable coherence of Xenophon’s concept of erōs despite the diversity of the types of manifestation and visible differences in framing between male-male and male-female relationships.In addition,it will be shown that the principle of self-mastery as a vital criterion for the evaluation of sexual conduct is subordinated to what Xenophon perceives as the primary purpose of sexual intercourse:the procreation of progeny. 展开更多
关键词 erōs AKRASIA paiderastia FRIENDSHIP MARRIAGE ADULTerY fatal love courtesans
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Development of NIR Responsive Upconversion Nanosensor for Turn-on Detection of 4-Nonylphenol
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作者 HUANG Sili XU Kuncheng +5 位作者 YE Yiwen WEN Hongli CHEN Rihui SONG Wei CHEN Wei ABDUR Raheem Aleem 《发光学报》 北大核心 2025年第1期140-155,共16页
4-Nonylphenol(NP)is a kind of estrogen belonging to the endocrine disrupter,widely used in various agricultural and industrial goods.However,extensive use of NP with direct release to environment poses high risks to b... 4-Nonylphenol(NP)is a kind of estrogen belonging to the endocrine disrupter,widely used in various agricultural and industrial goods.However,extensive use of NP with direct release to environment poses high risks to both human health and ecosystems.Herein,for the first time,we developed near-infrared(NIR)responsive upconversion luminescence nanosensor for NP detection.The Förster resonance energy transfer based upconversion nanoparticles(UCNPs)-graphene oxide sensor offers highly selective and sensitive detection of NP in linear ranges of 5−200 ng/mL and 200−1000 ng/mL under 980 nm and 808 nm excitation,respectively,with LOD at 4.2 ng/mL.The sensors were successfully tested for NP detection in real liquid milk samples with excellent recovery results.The rare-earth fluoride based upconversion luminescence nanosensor with NIR excitation wavelength,holds promise for sensing food,environmental,and biological samples due to their high sensitivity,specific recognition,low LOD,negligible autofluorescence,along with the deep penetration of NIR excitation sources. 展开更多
关键词 er^(3+)/Yb^(3+)/Nd^(3+) upconversion nanoparticles Förster resonance energy transfer ESTROGEN DETECTION
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ERβ/JNK通路介导的杜仲提取物对APP/PS1双转基因小鼠学习记忆能力的影响 被引量:1
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作者 李月 张莉莉 +6 位作者 赵灿 赵红梅 王堰 付金蕾 张杰 张宁 徐红丹 《中国中药杂志》 北大核心 2025年第2期285-292,共8页
研究杜仲提取物对APP/PS1双转基因小鼠空间学习障碍的改善作用及探讨其与雌激素受体β(ERβ)/c-Jun氨基末端激酶(JNK)信号通路的关系。将60只3月龄雄性APP/PS1小鼠随机分为模型组、抗脑衰胶囊组(0.585 g·kg^(-1))、盐酸多奈哌齐组(... 研究杜仲提取物对APP/PS1双转基因小鼠空间学习障碍的改善作用及探讨其与雌激素受体β(ERβ)/c-Jun氨基末端激酶(JNK)信号通路的关系。将60只3月龄雄性APP/PS1小鼠随机分为模型组、抗脑衰胶囊组(0.585 g·kg^(-1))、盐酸多奈哌齐组(0.65 mg·kg^(-1))、杜仲提取物组(1.3 g·kg^(-1));15只相同遗传背景的C57BL/6小鼠为野生(WT)对照组。通过水迷宫实验(MWM)、避暗实验(PAT)及新物体识别实验(NOR)评估小鼠学习记忆能力;苏木精-伊红(HE)染色及透射电镜(TEM)观察小鼠海马区组织形态和细胞超微结构特征;将关键活性成分与关键靶点利用AutoDock Vina软件进行分子对接验证;免疫组化方法(IHC)检测小鼠海马齿状回(DG)区中ERβ表达;蛋白免疫印迹法(WB)检测小鼠海马区ERβ、p-JNK、JNK的表达情况。与WT对照组相比,模型组小鼠在MWM中逃避潜伏期显著延长、穿越平台次数和目标象限停留时间显著减少,PAT中逃避潜伏期显著减少、错误次数显著增加,NOR中新物体识别指数显著降低;HE染色结果表明,模型组小鼠海马区出现神经元数目减少,锥体细胞排列紊乱,细胞核固缩等变化;TEM检测结果表明,模型组海马区部分神经元细胞核有固缩状态,核膜略微增厚和畸变,胞质内尼氏体较少;IHC结果表明,模型组小鼠海马DG区ERβ表达显著降低;WB结果表明,海马组织ERβ的表达降低,p-JNK/JNK水平升高。与模型组相比,杜仲提取物组小鼠在MWM中逃避潜伏期显著缩短、穿越平台次数和目标象限停留时间显著增加,PAT中逃避潜伏期显著增加、错误次数显著减少,NOR中新物体识别指数显著提高;小鼠海马区出现神经元数目增多,锥体细胞排列趋于有序;海马区神经元细胞核状态较好;小鼠海马DG区ERβ表达显著升高;海马组织ERβ的表达显著升高,p-JNK/JNK水平显著降低。盐酸多奈哌齐和抗脑衰胶囊对APP/PS1小鼠在行为学、HE、TEM实验指标中的作用与杜仲提取物作用相似,在IHC和WB实验中,盐酸多奈哌齐组与模型组没有明显差异。分子对接结果表明,杜仲提取物中雌激素类成分与ERβ结合紧密。综上所述,杜仲提取物与雌激素受体结合,调节ERβ的表达,激活ERβ/JNK信号通路可能是其改善APP/PS1小鼠学习记忆能力的关键机制之一。 展开更多
关键词 杜仲提取物 阿尔茨海默病 APP/PS1 erΒ JNK
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Wear performance and microstructures of Fe-Cr-C alloy cladding on heterogeneous welded joints of NM450/ER70-G/ZG30SiMn
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作者 Ning Xiao Yujie Tao +3 位作者 Yiheng Liu Haoyu Kong Qingjie Sun Ninshu Ma 《China Welding》 2025年第4期1-13,共13页
This work employed Fe-Cr-C alloy as the cladding material to fabricate wear-resistant coatings on dissimilar steel welded joints composed of NM450 wear-resistant steel and ZG30 SiMn cast steel with ER70-G welding wire... This work employed Fe-Cr-C alloy as the cladding material to fabricate wear-resistant coatings on dissimilar steel welded joints composed of NM450 wear-resistant steel and ZG30 SiMn cast steel with ER70-G welding wire.The investigation focused on elucidating the effect of dilution ratio levels on microstructural distribution and wear behavior within this heterogeneous multi-material system.Owing to its inherently higher chromium(Cr)content,the NM450 region demonstrated more pronounced carbide formation compared to the ER70-G and ZG30 SiMn regions.Microstructural analysis revealed that Cr_(7)C_(3) carbides predominantly formed along grain boundaries,whereas Cr_(23)C_(6) carbides mainly precipitated within grains.After cladding,the wear resistance of the NM450/ER70-G/ZG30 SiMn welded joint was markedly improved,with the high-dilution coating exhibiting superior performance.This enhancement was attributed to favorable thermal conditions in the highdilution scenario,promoting a more homogeneous precipitation of Cr_(23)C_(6).Although significant elemental mixing occurred at the interfacial zones,the top region of the cladding layer remained minimally affected by dilution-induced drawbacks.Accordingly,the high-dilution sample demonstrated better wear resistance than its low-dilution counterpart due to optimized carbide precipitation characteristics.These findings provide basic insights for designing effective cladding strategies for complex multi-material components in demanding industrial applications. 展开更多
关键词 Fe-Cr-C alloy cladding NM450/er70-G/ZG30SiMn heterogeneous joint Dilution ratio Microstructural characteristics Wear performance
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ER-induced PERK/TFEB cascade sequentially modulates mitochondrial dynamics during cranial suture expansion
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作者 Jingyi Cai Ziyang Min +3 位作者 Chaoyuan Li Zhihe Zhao Jun Liu Dian Jing 《Bone Research》 2025年第6期1485-1498,共14页
The effectiveness of cranial suture expansion therapy hinges on the timely and adequate regeneration of bone tissue in response to mechanical stimuli.To optimize clinical outcomes and prevent post-expansion relapse,we... The effectiveness of cranial suture expansion therapy hinges on the timely and adequate regeneration of bone tissue in response to mechanical stimuli.To optimize clinical outcomes and prevent post-expansion relapse,we delved into the underlying mechanisms governing bone remodeling during the processes of suture expansion and relapse.Our findings revealed that in vitro stretching bolstered mesenchymal stem cells'antioxidative and osteogenic capacity by orchestrating mitochondrial activities,which governed by force-induced endoplasmic reticulum(ER)stress.Nonetheless,this signal transduction occurred through the activation of protein kinase R-like ER kinase(PERK)at the ER-mitochondria interface,rather than ER-mitochondria calcium flow as previously reported.Subsequently,PERK activation triggered TFEB translocation to the nucleus,thus regulating mitochondrial dynamics transcriptionally.Assessment of the mitochondrial pool during expansion and relapse unveiled a sequential,two-phase regulation governed by the ER stress/p-PERK/TFEB signaling cascade.Initially,PERK activation facilitated TFEB nuclear localization,stimulating mitochondrial biogenesis through PGC1-α,thereby addressing energy demands during the initial phase.Subsequently,TFEB shifted focus towards ensuring adequate mitophagy for mitochondrial quality maintenance during the remodeling process.Premature withdrawal of expanding force disrupted this sequential regulation,leading to compromised mitophagy and the accumulation of dysfunctional mitochondria,culminating in suboptimal bone regeneration and relapse.Notably,pharmacological activation of mitophagy effectively mitigated relapse and attenuated bone loss,while its inhibition impeded anticipated bone growth in remodeling progress.Conclusively,we elucidated the ER stress/p-PERK/TFEB signaling orchestrated sequential mitochondria biogenesis and mitophagy under mechanical stretch,thus ensuring antioxidative capacity and osteogenic potential of cranial suture tissues. 展开更多
关键词 mitochondrial dynamics regeneration bone tissue mesenchymal stem cellsantioxidative vitro stretching er induced perk TFEB cascade cranial suture expansion bone remodeling cranial suture expansion therapy
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Luminescence enhancement effects of Ca_(x)Sr_(2-x)Nb_(2)O_(7):Er^(3+),Tm^(3+) phosphors for temperature sensing and anti-counterfeiting applications
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作者 Wenchao Chen Huabo Gao +5 位作者 Maxim S.Molokeev Qi Chen Xiangpeng Geng Lefu Mei Xin Min Bin Ma 《Journal of Rare Earths》 2025年第7期1345-1354,共10页
Er^(3+)-and Tm^(3+)-doped Ca_(x)Sr_(2-x)Nb_(2)O_(7)(C_(x)S_(2-x)N,x=0.6,0.8,1,0,1.2,1,4) phosphors with layered pe rovskite structure were designed.These phosphors exhibit a dominant emission peak at 549 nm under980 n... Er^(3+)-and Tm^(3+)-doped Ca_(x)Sr_(2-x)Nb_(2)O_(7)(C_(x)S_(2-x)N,x=0.6,0.8,1,0,1.2,1,4) phosphors with layered pe rovskite structure were designed.These phosphors exhibit a dominant emission peak at 549 nm under980 nm laser excitation,attributed to the^(4)S_(3/2)→^(4)I_(15/2)transition.By increasing the content of Ca^(2+),the crystal field regulation of rare earth ions is realized and the luminescence enhancement is induced,which is manifested by the increase of^(2)H_(11/2),^(4)S_(3/2)→^(4)I_(15/2)emission.Furthermore,the temperature sensing sensitivities of C_(0.6)S_(1.4)N:Er,Tm and C_(0.6)S_(1.4)N:Er,Tm based on non-thermally coupled energy levels were studied.Finally,an anti-counterfeiting imprint was prepared using phosphors,which have high brightness and excellent photothermal stability.This work not only confirms that closer ionic radii substitution enables to increase the electronic density of states,improve the crystal field symmetry and enhance the luminescence,but also provides a promising phosphor system for temperature sensing and anti-counterfeiting applications,opening up new prospects in the optimization of the optical properties of phosphors. 展开更多
关键词 Ca_(x)Sr_(2-x)Nb_(2)O_(7):er Tm phosphor Luminescence enhancement Crystal field Temperature sensing ANTI-COUNTerFEITING Rare earths
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