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Highly Efficient Broadband Achromatic Microlens Design Based on Low-Dispersion Materials
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作者 Xueqian Wang Chuanbao Liu +7 位作者 Feilou Wang Weijia Luo Chengdong Tao Yuxuan Hou Lijie Qiao ji zhou jingbo Sun Yang Bai 《Engineering》 SCIE EI CAS CSCD 2024年第7期194-200,共7页
Metalenses with achromatic performance offer a new opportunity for high-quality imaging with an ultracompact configuration;however,they suffer from complex fabrication processes and low focusing efficiency.In this stu... Metalenses with achromatic performance offer a new opportunity for high-quality imaging with an ultracompact configuration;however,they suffer from complex fabrication processes and low focusing efficiency.In this study,we propose an efficient design method for achromatic microlenses on a wavelength scale using materials with low dispersion,an adequately designed convex surface,and a thickness profile distribution.By taking into account the absolute chromatic aberration,relative focal length shift(FLS),and numerical aperture(NA),microlens with a certain focal length can be realized through our realized map of geometric features.Accordingly,the designed achromatic microlenses with low-dispersion fused silica were fabricated using a focused ion beam,and precise surface profiles were obtained.The fabricated microlenses exhibited a high average focusing efficiency of 65%at visible wavelengths of 410-680 nm and excellent achromatic capability via white light imaging.Moreover,the design exhibited the advantages of being polarization-insensitive and near-diffraction-limited.These results demonstrate the effectiveness of our proposed achromatic microlens design approach,which expands the prospects of miniaturized optics such as virtual and augmented reality,ultracompact microscopes,and biological endoscopy. 展开更多
关键词 Broadband achromatic focusing Metamaterials Low dispersion materials Visible wavelength MICROLENSES
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Highly Thermally Conductive and Structurally Ultra‑Stable Graphitic Films with Seamless Heterointerfaces for Extreme Thermal Management
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作者 Peijuan Zhang Yuanyuan Hao +17 位作者 Hang Shi jiahao Lu Yingjun Liu Xin Ming Ya Wang Wenzhang Fang Yuxing Xia Yance Chen Peng Li Ziqiu Wang Qingyun Su Weidong Lv ji zhou Ying Zhang Haiwen Lai Weiwei Gao Zhen Xu Chao Gao 《Nano-Micro Letters》 SCIE EI CSCD 2024年第3期383-397,共15页
Highly thermally conductive graphitic film(GF)materials have become a competitive solution for the thermal management of high-power electronic devices.However,their catastrophic structural failure under extreme altern... Highly thermally conductive graphitic film(GF)materials have become a competitive solution for the thermal management of high-power electronic devices.However,their catastrophic structural failure under extreme alternating thermal/cold shock poses a significant challenge to reliability and safety.Here,we present the first investigation into the structural failure mechanism of GF during cyclic liquid nitrogen shocks(LNS),which reveals a bubbling process characterized by“permeation-diffusion-deformation”phenomenon.To overcome this long-standing structural weakness,a novel metal-nanoarmor strategy is proposed to construct a Cu-modified graphitic film(GF@Cu)with seamless heterointerface.This well-designed interface ensures superior structural stability for GF@Cu after hundreds of LNS cycles from 77 to 300 K.Moreover,GF@Cu maintains high thermal conductivity up to 1088 W m^(−1)K^(−1)with degradation of less than 5%even after 150 LNS cycles,superior to that of pure GF(50%degradation).Our work not only offers an opportunity to improve the robustness of graphitic films by the rational structural design but also facilitates the applications of thermally conductive carbon-based materials for future extreme thermal management in complex aerospace electronics. 展开更多
关键词 Highly thermally conductive Structurally ultra-stable Graphitic film Extreme thermal management Liquid nitrogen bubbling
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Advanced Machine Learning Methods for Prediction of Blast-Induced Flyrock Using Hybrid SVR Methods
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作者 ji zhou Yijun Lu +3 位作者 Qiong Tian Haichuan Liu Mahdi Hasanipanah jiandong Huang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1595-1617,共23页
Blasting in surface mines aims to fragment rock masses to a proper size.However,flyrock is an undesirable effect of blasting that can result in human injuries.In this study,support vector regression(SVR)is combined wi... Blasting in surface mines aims to fragment rock masses to a proper size.However,flyrock is an undesirable effect of blasting that can result in human injuries.In this study,support vector regression(SVR)is combined with four algorithms:gravitational search algorithm(GSA),biogeography-based optimization(BBO),ant colony optimization(ACO),and whale optimization algorithm(WOA)for predicting flyrock in two surface mines in Iran.Additionally,three other methods,including artificial neural network(ANN),kernel extreme learning machine(KELM),and general regression neural network(GRNN),are employed,and their performances are compared to those of four hybrid SVR models.After modeling,the measured and predicted flyrock values are validated with some performance indices,such as root mean squared error(RMSE).The results revealed that the SVR-WOA model has the most optimal accuracy,with an RMSE of 7.218,while the RMSEs of the KELM,GRNN,SVR-GSA,ANN,SVR-BBO,and SVR-ACO models are 10.668,10.867,15.305,15.661,16.239,and 18.228,respectively.Therefore,combining WOA and SVR can be a valuable tool for accurately predicting flyrock distance in surface mines. 展开更多
关键词 Flyrock induced by blasting optimization algorithms SVR GRNN
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企业数字技术应用的减污降碳协同效应研究
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作者 卿玲丽 季周 张雯悦 《财经理论与实践》 CSSCI 北大核心 2024年第4期136-143,共8页
依据2010—2022年中国沪深A股上市公司面板数据,运用双向固定效应模型,考量数字技术应用的减污降碳协同效应及首席数据官调节作用。结果显示:企业数字技术应用通过提升绿色技术创新和改善ESG绩效,降低污染物排放及碳排放效应显著,设立... 依据2010—2022年中国沪深A股上市公司面板数据,运用双向固定效应模型,考量数字技术应用的减污降碳协同效应及首席数据官调节作用。结果显示:企业数字技术应用通过提升绿色技术创新和改善ESG绩效,降低污染物排放及碳排放效应显著,设立首席数据官强化了这一效应;异质性检验显示,减污降碳协同效应在中小规模企业、非重污染行业以及东部地区企业更为显著。鉴于此,建议强化企业ESG绩效考核,进一步加大数字技术应用力度,鼓励绿色技术创新。 展开更多
关键词 数字技术 减污降碳 协同效应 首席数据官
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Extremely efficient terahertz second-harmonic generation from organic crystals
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作者 Hang Zhao Yong Tan +4 位作者 Chen Wang Ming Liu Yongzheng Wen Yuejin Zhao ji zhou 《Advanced Photonics Nexus》 2024年第4期82-91,共10页
Achieving efficient and intense second-harmonic generation(SHG)in the terahertz(THz)spectrum holds great potential for a wide range of technical applications,including THz nonlinear functional devices,wireless communi... Achieving efficient and intense second-harmonic generation(SHG)in the terahertz(THz)spectrum holds great potential for a wide range of technical applications,including THz nonlinear functional devices,wireless communications,and data processing and storage.However,the current research on THz harmonic emission primarily focuses on inorganic materials,which often offers challenges in achieving both efficient and broadband SHG.Herein,the remarkable efficiency of organic materials in producing THz harmonics is studied and demonstrated,thereby opening up a new avenue for searching candidates for frequency-doubling devices in the THz band.By utilizing DAST,DSTMS,and OH1 crystals,we showcase their superior frequency conversion capabilities when pumped by the narrowband THz pulses centered at 2.4,1.6,and 0.8 THz.The SHG spans a high-frequency THz domain of 4.8 THz,achieving an unprecedented conversion efficiency of∼1.21%while maintaining a perturbative nonlinear response.The highly efficient SHG of these materials is theoretically analyzed by considering the combined effects of dispersion,phonon absorption,polarization,and the nonlinear susceptibility of organic crystals.This work presents a promising platform for efficient THz frequency conversion and generation across a wide range of frequencies,offering new opportunities for novel nonlinear THz applications in next-generation electronics and optics. 展开更多
关键词 TERAHERTZ organic crystal second-harmonic generation
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陕西省食品中污染物限量使用情况跟踪评价研究 被引量:2
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作者 南静 池方方 +4 位作者 冀州 张路钱 董潇妮 王妍昕 张瑞娟 《国外医学(医学地理分册)》 CAS 2017年第4期317-320,共4页
目的为了解陕西省监管部门、检验单位、生产企业3类人员对食品安全国家标准《食品中污染物限量GB2762-2012》的执行情况、理解能力和依从情况,及时推进标准的贯彻实施,调查标准的科学性和实用性,为实施标准和适时组织标准的修订提供参... 目的为了解陕西省监管部门、检验单位、生产企业3类人员对食品安全国家标准《食品中污染物限量GB2762-2012》的执行情况、理解能力和依从情况,及时推进标准的贯彻实施,调查标准的科学性和实用性,为实施标准和适时组织标准的修订提供参考。方法采用横断面调查法,于2016年4月通过发放统一设计的问卷开展调查。调查对象为随机抽取陕西省各市的食品安全监管人员、食品检验人员、食品生产企业技术人员。调查内容包括调查对象基本情况,调查对象对标准条款的理解以及在标准执行过程中遇到的主要问题,修改意见和建议等。本次调查中共发放问卷170份,收回有效调查问卷157份,回收率92.4%。其中各科研检验监督单位发放了120份,回收113份,回收率94.2%。各生产企业共发放问卷50份,回收44份,回收率88.0%。回收后的调查问卷统一编号,问卷的录入采用Epidata 3.1软件进行,用SPSS软件对数据进行统计分析。并及时将汇总后的意见建议反馈给国家卫计委食品安全风险评估中心网站。结果 (1)经数据分析,食品相关检验科研人员本科及以上占83.2%;相关食品企业人员学历在大专及以下占40.9%。(2)经统计学分析,检验科研人员与企业人员对标准的知晓、满意情况差异均有统计学差异。两类人员对标准有较高的知晓率,分别占80.5%、88.6%;并且对标准有较高的满意度,分别占75.2%、88.6%。(3)经统计分析结果显示,检验科研人员与企业人员对汞、镉、苯并[a]芘三项污染物指标限量值的合理性评价差异有统计学意义(P<0.01)。其中检验科研人员认为镉限量值合理性最高,占比81.4%,苯并[a]芘限量值合理性最低,占比67.3%;企业人员认为汞限量值合理性最高,占比86.4%,苯并[a]芘合理性最低,占比50.0%。(4)调查对象在标准使用过程中遇到了技术性问题,排在前两位的问题主要是食品分类问题、主观判断指标。结论食品企业从业人员较科研机构人员学历稍低;食品从业人员对标准的满意度及知晓情况较好;调查对象均认为苯并[a]芘限量值的合理性较低;食品分类问题还需继续细分归类。 展开更多
关键词 食品安全国家标准 调查 跟踪评价
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光场成像回波解调比法抑制光强扰动像质退化
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作者 程志远 纪洲 +3 位作者 高彦生 苏华 闫佩佩 夏爱利 《光子学报》 EI CAS CSCD 北大核心 2022年第12期24-35,共12页
新型激光光场成像系统受激光光束光强起伏影响成像像质下降,为抑制激光束光强扰动引起的像质退化效应,先对光场回波信号进行解调处理,再进行多光束相位闭合求解相位闭合系数,然后依据频谱迭代理论,推导建立基于光束光强扰动因子的频谱... 新型激光光场成像系统受激光光束光强起伏影响成像像质下降,为抑制激光束光强扰动引起的像质退化效应,先对光场回波信号进行解调处理,再进行多光束相位闭合求解相位闭合系数,然后依据频谱迭代理论,推导建立基于光束光强扰动因子的频谱重建模型,揭示了光束光强扰动因子对光场成像频谱的影响机理。提出了一种基于激光回波光场信号解调比求解方法,抑制光强振幅扰动因子引起的频谱重建误差,间接提高光场重构成像像质,并采用多种像质评估方法进行像质评价。通过仿真和桌面实验平台对回波解调比方法进行了实验验证,结果表明解调比法抑制光强扰动后,重构图像斯特列尔比、峰值信噪比、结构相似度像质评价指标均得到有效提升。该方法可有效抑制光束光强抖动引起的像质退化效应并提高激光光场成像像质,可为光场成像技术像质提升和工程应用转化提供技术支撑。 展开更多
关键词 光场成像 光束光强扰动 频谱重建误差 成像质量 解调信号
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β-联蛋白促进大鼠外周血间充质干细胞存活及扩增 被引量:6
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作者 赵岚 季洲 +3 位作者 张锐 崔进 黄伟光 张少衡 《中国生物化学与分子生物学报》 CAS CSCD 北大核心 2019年第8期880-887,共8页
本研究旨在探讨β-联蛋白在促进外周血间充质干细胞(PBMSCs)的存活和扩增中的作用。采取SD大鼠外周血,分离培养得到PBMSCs,随机将细胞分3组:未处理组(CON)、β-联蛋白激动剂组(WAY-262611,WAY)和β-联蛋白抑制剂组(XAV-939,XAV)。体外培... 本研究旨在探讨β-联蛋白在促进外周血间充质干细胞(PBMSCs)的存活和扩增中的作用。采取SD大鼠外周血,分离培养得到PBMSCs,随机将细胞分3组:未处理组(CON)、β-联蛋白激动剂组(WAY-262611,WAY)和β-联蛋白抑制剂组(XAV-939,XAV)。体外培养90 d,观察各组细胞增生和凋亡情况。应用Western印迹和ELISA方法观察细胞衰老标记性蛋白质p16和p21表达情况,以及β-联蛋白信号通路分子表达情况。外周血经过3代培养,可获得纯度较高的PBMSCs,体外培养40 d即发生衰老和凋亡,但WAY-262611可延长细胞存活时间至90 d以上,增加其体外增殖率1. 08倍(P<0. 05),明显提高细胞增殖能力(P<0. 05);使WAY组p21和p16蛋白含量较CON组减少72. 1%和68. 4%(两者均P<0. 05),较XAV组减低92. 9%和93. 3%(两者均P<0. 05)。与CON组比较,WAY组衰老细胞数减少61. 4%(P<0. 05),而XAV组则增加53. 3%(P<0. 05);WAY组细胞凋亡率减少50. 2%(P<0. 05),而XAV组细胞凋亡率增加35. 7%(P<0. 05);WAY组β-联蛋白表达水平增加2. 2倍(P<0. 05),而XAV组则降低77. 7%(P<0. 05)。WAY-262611可升高WAY组β-联蛋白磷酸化水平(包括p-Ser552和p-Ser675) 97%和79%(两者均P<0. 05),升高抗凋亡蛋白质Bcl2表达水平1. 39倍(P<0. 05),降低凋亡蛋白Bax和胱天蛋白酶3表达67. 6%和83. 3%(两者均P<0. 05);而XAV-939则降低Bcl2蛋白表达水平69. 1%(P<0. 05),升高Bax和胱天蛋白酶3表达水平1. 27倍和1. 02倍(两者均P<0. 05)。β-联蛋白可能是影响MSCs存活和增殖的重要信号途径。这些发现可能有助于提高用于组织工程的PB-MSCs的体外生产。 展开更多
关键词 β-联蛋白 外周血间充质干细胞 凋亡 扩增
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FOXC1在监测恶性肿瘤预后中的生物学意义 被引量:2
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作者 季州 韦建瑞 张少衡 《中国生物化学与分子生物学报》 CAS CSCD 北大核心 2020年第5期519-526,共8页
叉头框(forkhead box,FOX)转录因子的异常表达在致癌过程中发挥至关重要的作用。叉头框蛋白质C1(FOXC1)是FOX的重要成员,在生物过程中起着重要作用,包括增殖、分化、凋亡、迁移、侵袭、新陈代谢和寿命。大量的证据表明,FOXC1异常表达有... 叉头框(forkhead box,FOX)转录因子的异常表达在致癌过程中发挥至关重要的作用。叉头框蛋白质C1(FOXC1)是FOX的重要成员,在生物过程中起着重要作用,包括增殖、分化、凋亡、迁移、侵袭、新陈代谢和寿命。大量的证据表明,FOXC1异常表达有助于多种恶性肿瘤的发生。FOXC1促进许多癌症的进展,例如乳腺癌、肝细胞癌和胃癌等。FOXC1还与肿瘤转移、分期、复发、预后评估及药物抵抗有关。FOXC1在肿瘤的发展和转移中发挥关键作用。临床研究表明,FOXC1表达升高与许多癌症亚型(例如基底样乳腺癌,Basal-like breast cancer,BLBC)的预后不良有关。FOXC1在BLBC中高度特异性表达,其在乳腺癌中的功能已被广泛探索。FOXC1也是非小细胞肺癌(non-small cell lung cancer,NSCLC)的独立预后因素,并在浸润和转移方面显示出其特有的生物学意义。FOXC1可以通过多种信号通路调节癌干细胞(cancer stem cells,CSCs)的生物学特性,通过介导细胞周期蛋白D1、c-Myc和NF-κB的表达,增加CSCs的增殖;与HOXA/B信号通路协同,促进肿瘤的发生和进展;通过上调WNT信号的转录介质β-联蛋白或激活非典型Hedgehog信号增强CSCs活性;通过上调NF-κB与诱导IL-6表达增强肿瘤对缺氧的适应;通过增加MMP7、NEDD9和Snail的表达促进癌症的转移;通过介导MST1R和KLF4表达促进癌症浸润;通过调控FGF19和MSX1基因表达参与肿瘤的进展;启动上皮-间质转化(epithelial-mesenchymal transition,EMT)基因标签驱动实体瘤的进展。本综述将总结FOXC1在肿瘤发展和进展中的功能和调控的当前进展,以及这些新发现在监测恶性肿瘤预后中的生物学意义。 展开更多
关键词 叉头框蛋白质C1 恶性肿瘤 进展 预后
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Combining computer vision and deep learning to enable ultra-scale aerial phenotyping and precision agriculture:A case study of lettuce production 被引量:20
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作者 Alan Bauer Aaron George Bostrom +6 位作者 Joshua Ball Christopher Applegate Tao Cheng Stephen Laycock Sergio Moreno Rojas Jacob Kirwan ji zhou 《Horticulture Research》 SCIE 2019年第1期906-917,共12页
Aerial imagery is regularly used by crop researchers,growers and farmers to monitor crops during the growing season.To extract meaningful information from large-scale aerial images collected from the field,high-throug... Aerial imagery is regularly used by crop researchers,growers and farmers to monitor crops during the growing season.To extract meaningful information from large-scale aerial images collected from the field,high-throughput phenotypic analysis solutions are required,which not only produce high-quality measures of key crop traits,but also support professionals to make prompt and reliable crop management decisions.Here,we report AirSurf,an automated and open-source analytic platform that combines modern computer vision,up-to-date machine learning,and modular software engineering in order to measure yield-related phenotypes from ultra-large aerial imagery.To quantify millions of in-field lettuces acquired by fixed-wing light aircrafts equipped with normalised difference vegetation index(NDVI)sensors,we customised AirSurf by combining computer vision algorithms and a deep-learning classifier trained with over 100,000 labelled lettuce signals.The tailored platform,AirSurf-Lettuce,is capable of scoring and categorising iceberg lettuces with high accuracy(>98%).Furthermore,novel analysis functions have been developed to map lettuce size distribution across the field,based on which associated global positioning system(GPS)tagged harvest regions have been identified to enable growers and farmers to conduct precision agricultural practises in order to improve the actual yield as well as crop marketability before the harvest. 展开更多
关键词 COMPUTER analysis equipped
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多界面耦合空心核壳MnCoSe_(x)/MnO@氮掺杂碳复合材料的制备及电化学性能
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作者 周济 张丽娜 +2 位作者 刘彬彬 徐彩霞 刘宏 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2023年第8期2471-2482,共12页
通过简单的溶剂热和硒化策略以及进一步的碳层包覆程序制备氮掺杂碳壳包裹的空心MnCoSe_(x)/MnO纳米球(MnCoSe_(x)/MnO@N-C)。得益于MnCoSe_(x)和MnO之间的多界面耦合以及独特的空心核壳结构,MnCoSe_(x)/MnO@N-C复合材料具有较高的比电... 通过简单的溶剂热和硒化策略以及进一步的碳层包覆程序制备氮掺杂碳壳包裹的空心MnCoSe_(x)/MnO纳米球(MnCoSe_(x)/MnO@N-C)。得益于MnCoSe_(x)和MnO之间的多界面耦合以及独特的空心核壳结构,MnCoSe_(x)/MnO@N-C复合材料具有较高的比电容和优异的倍率性能,即使在5 A/g的高电流密度下,MnCoSe_(x)/MnO@N-C仍可以稳定运行20000次循环,并保持84.6%的初始比电容。由MnCoSe_(x)/MnO@N-C和活性炭组装的非对称超级电容器器件在功率密度为810 W/kg时表现出11.2 W·h/kg的高能量密度,并拥有超长的循环寿命,在20000次循环后仍可保留初始比电容的84.0%。 展开更多
关键词 硒化物 空心纳米球 氮掺杂碳 正极 超级电容器 电化学性能
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Metamaterials:From Engineered Materials to Engineering Materials 被引量:3
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作者 John Pendry ji zhou jingbo Sun 《Engineering》 SCIE EI CAS 2022年第10期1-2,共2页
As a new frontier in materials science,metamaterials have experienced a boom in the past two decades.This research field began with artificially structured materials exhibiting extraordinary electromagnetic properties... As a new frontier in materials science,metamaterials have experienced a boom in the past two decades.This research field began with artificially structured materials exhibiting extraordinary electromagnetic properties unavailable in nature;now,it extends to a large family of artificial-material systems with wide-ranging,extraordinary,and outstanding properties for applications in fields such as electromagnetics,optics,mechanics. 展开更多
关键词 ENGINE FRONTIER OPTICS
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全科医学生人文素质教育课程的重要性和满意度分析 被引量:10
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作者 苏健 徐冰 +2 位作者 季州 吴玢潼 左中夫 《中国继续医学教育》 2019年第4期31-32,共2页
目的探讨全科医学生对人文素质教育课程的重要性和满意度情况,分析原因并提出建议。方法选取2015级全科医学专业学生110例作为调查对象,对我校开设的人文素质课程(思想政治、医学伦理学、医学沟通学、公共事业管理、医学法律、社区医学... 目的探讨全科医学生对人文素质教育课程的重要性和满意度情况,分析原因并提出建议。方法选取2015级全科医学专业学生110例作为调查对象,对我校开设的人文素质课程(思想政治、医学伦理学、医学沟通学、公共事业管理、医学法律、社区医学、卫生经济学)的重要性及满意度进行评分。结果调查对象对医学法律、医学沟通学以及社区医学课程的重要性评分较高,分别为(4.02±0.28)分、(3.87±0.31)分和(3.79±0.30)分,高于其他各门课程重要性评分,差异有统计学意义(P <0.05);调查对象对人文素质各课程的满意度评分均较低,其中公共事业管理和社区医学课程满意度评分高于其他各门课程,差异均有统计学意义(P <0.05)。结论全科医学生认为人文素质教育较为重要,但对各课程的满意度较低,医学院校把人文素质的培养作为全科医学系建设的重点,积极完善课程设置,改变授课形式,并加大教师的培训力度,进一步加强全科医学生的人文素质教育。 展开更多
关键词 全科医学 人文素质 课程 重要性 满意度 分析
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人文教育对全科医学生实习效果的观察 被引量:9
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作者 苏健 徐冰 +2 位作者 季州 吴玢潼 左中夫 《中国继续医学教育》 2019年第7期60-62,共3页
目的探讨人文教育对全科医学生在神经内科实习的效果评价。方法选取2013级我校所有全科医学专业学生68例作为研究对象,随机分为观察组(34例)和对照组(34例),两组实习生均在神经内科进行临床实习,观察组实习生在此基础上,增加人文素质教... 目的探讨人文教育对全科医学生在神经内科实习的效果评价。方法选取2013级我校所有全科医学专业学生68例作为研究对象,随机分为观察组(34例)和对照组(34例),两组实习生均在神经内科进行临床实习,观察组实习生在此基础上,增加人文素质教育内容。出科前评价两组实习生的人文素质能力、临床实习效果以及实习满意度。结果观察组实习生医德医风素养(96.75±2.08)分、沟通交流能力(88.69±6.18)分、医学法律常识(86.04±6.75)分以及团队协作能力(92.15±5.68)分等人文素质教育的评分均高于对照组,差异有统计学意义(P <0.05);观察组实习生临床知识得分(91.59±4.68)分、综合能力评价得分(92.27±6.28)分以及实习满意度评分(4.62±0.33)分均高于对照组,差异有统计学意义(P <0.05)。结论全科医学实习生在神经内科接受人文素质课程学习后,可有效提高人文素质以及临床实习效果。 展开更多
关键词 人文教育 全科医学 实习 神经内科 效果 满意度
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Surface coal mining impacts on land use change and ecological service value:a case study in Shengli coalfield,Inner Mongolia 被引量:1
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作者 Lijia Zhang Xu zhou +8 位作者 Yan zhou ji zhou jiwang Guo Zihan Zhai Yan Chen Xiangyan Su Lingxiao Ying Liwei Wang Ying Qiao 《International Journal of Coal Science & Technology》 EI CAS CSCD 2022年第5期172-186,共15页
Coal plays a crucial role in global economic development and remains the most common and widely distributed fossil fuel worldwide.As the world's largest developing country,China's mining and utilization of coa... Coal plays a crucial role in global economic development and remains the most common and widely distributed fossil fuel worldwide.As the world's largest developing country,China's mining and utilization of coal resources have contributed signifcantly to the country’s rapid economic growth.Inner Mongolia is an ecologically fragile arid and semi-arid area of China.The exploitation of opencast mining has seriously hindered the sustainable use of regional land and the residents'well-being.Using ENVI-based remote sensing images from 2000,2005,2010,2015,and 2020,this study employed a random forest algorithm to divide land utilization types into construction land,vegetation,cultivated land,bare land,and water areas and analyzed the characteristics of land use and ecosystem service value changes over the past 20 years.The results were as follows:(1)Construction land in the mining area changed minimally from 2000 to 2020;vegetation and water bodies showed a decreasing trend,whereas bare and cultivated lands showed an increasing trend.Bare land exhibited the largest change in area proportion and water bodies the smallest.(2)The total ecosystem service value of the mining area declined from 10.939 to 9.527 billion Yuan.Vegetation ecosystem service value was the highest,followed by cultivated land and water,with the bare land ecosystem service value the lowest.(3)On a spatial scale,the total ecosystem service value of the Shengli mining area decreased year by year,indicating that land use changes in the mining area do have an impact on ecosystem service value. 展开更多
关键词 ESV Land use change Transformed matrix Spatial and temporal change
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Refractive index of ionic liquids under electric field:Methyl propyl imidazole iodide and several derivatives
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作者 ji zhou Shi-Kui Dong +1 位作者 Zhi-Hong He Yan-Hu Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第4期477-487,共11页
Ionic liquids have received wide attention due to their novel optoelectronic structures and devices as an optical means of regulating electricity.However,the quantitative testing and analysis of refractive index of io... Ionic liquids have received wide attention due to their novel optoelectronic structures and devices as an optical means of regulating electricity.However,the quantitative testing and analysis of refractive index of ionic liquids under electric field are rarely carried out.In the present study,an experimental apparatus including a hollow prism is designed to measure the refractive indices of ionic liquids under different electric fields.Five groups of imidazole ionic liquids are experimentally investigated and an inversion is performed to determine the refractive indices under electric fields.The error propagation analysis of the apex angle and the minimum deflection angle are conducted,and the machining accuracy requirements of the hollow prism are determined.The results show that the refractive indices of imidazole ionic liquids change with the light wavelength,following a downward convex parabola.Furthermore,the refractive index decreases with the carbon chain length of ionic liquid at a given wavelength,presenting an order of C3MImI>C4MImI>C5MImI>C3MImBr>C3MImBF4.Notably,the refractive index of imidazole ionic liquid exhibits a nonlinear change with the applied voltage at 546 nm and a monotonical decrease at 1529 nm.Besides,the variation of refractive index at 1529 nm with the applied voltage is larger than that at 546 nm and 1013 nm.Importantly,the variation of refractive index is contrary to that of absorption coefficient under electric field.This study illustrates that the theory of electrode and carrier transport can be used to explain the law of variation of n–k value of ionic liquid under the electric field,and provides the support for the evaluation of physical properties of ionic liquids,the measurement of optical functional parameters and the regulation of electric–optic performances of optical devices. 展开更多
关键词 IONIC liquid refractive index ELECTRO-OPTICAL property uncertainty propagation analysis
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Light absorption coefficients of ionic liquids under electric field
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作者 ji zhou Shi-Kui Dong +2 位作者 Zhi-Hong He Ju-Lius Caesar Puoza Yan-Hu Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第1期608-619,共12页
Ionic liquids have attracted a lot of research attention for their applications in novel optoelectronic structures and devices as an optical means of regulating electricity. Although the electro-optic effect of ionic ... Ionic liquids have attracted a lot of research attention for their applications in novel optoelectronic structures and devices as an optical means of regulating electricity. Although the electro-optic effect of ionic liquids is mentioned in some literature, quantitative testing and analysis are hardly found in light absorption coefficients of ionic liquids under an electric field. In the present study, an experimental apparatus is designed to measure the absorption coefficients of ionic liquids under different electric fields. Five groups of imidazole ionic liquids are experimentally investigated and an inversion is performed to determine the spectral absorption coefficients of the imidazole ionic liquids under the electric fields. Different intensities with multiple interface refractions and reflections are also considered, and the various measurement errors are analyzed through uncertainties propagation analysis. Spectral absorptions of ionic liquids from 300 nm to 2500 nm are obtained and the absorption coefficients are retrieved. It is found that the absorption behavior of ionic liquids changes in some frequency bands under an applied electric field. The experimental results show that the absorption coefficient of the ionic liquid increases with the voltage increasing at 1520 nm and 1920 nm. The change rate is affected by the types of anions and cations in the ionic liquid and the diffusion rate of the ions therein. This study provides illustrations for the ionic liquid-based electro-optical regulation in terms of physical property parameters and the testing technique. 展开更多
关键词 IONIC liquid ABSORPTION COEFFICIENT ELECTRO-OPTICAL property uncertainty propagation analysis
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Influence of Terabit Signal in Hybrid System with Multi-Rate and Multi-Modulation Format Channels
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作者 Fei Xu Yaojun Qiao +1 位作者 ji zhou Huiping Tian 《China Communications》 SCIE CSCD 2016年第11期189-196,共8页
We proposed a hybrid transmission system consist of 1Tbit/s Nyquist WDM channels,100Gbit/s PDM-QPSK WDM channels and 10Gbit/s NRZ WDM channels to study whether Terabit Nyquist WDM signal could transmit in the existing... We proposed a hybrid transmission system consist of 1Tbit/s Nyquist WDM channels,100Gbit/s PDM-QPSK WDM channels and 10Gbit/s NRZ WDM channels to study whether Terabit Nyquist WDM signal could transmit in the existing hybrid systems with DCM(dispersion compensation module). The simulation results demonstrated the influence of all these three kinds of signals. The 1Tbit/s Nyquist WDM channels introduced 1.5d B Q penalty to the 100Gbit/s PDM-QPSK signals and their influence on the 10Gbit/s NRZ signals was extremely slight. In the hybrid optical system,1Tbit/s Nyquist channel has 5d B Q penalty due to the inline DCM and 2.5d B Q penalty due to the channel interference from existing channels. Therefore,the total Q penalty is 7.5d B caused by strong nonlinear effects at the launch power of 0d Bm. The results have the guiding significance for the design of future backbone system and also support the feasibility of future dynamic optical system. 展开更多
关键词 hybrid optical system Terabit transmission Nyquist signal WDM
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IFT140^(+)/K14^(+) cells function as stem/progenitor cells in salivary glands
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作者 Xueming Zhang ji zhou +3 位作者 Xinyu Wang jiangyu Geng Yubei Chen Yao Sun 《International Journal of Oral Science》 SCIE CAS CSCD 2022年第4期561-571,共11页
Stem/progenitor cells are important for salivary gland development, homeostasis maintenance, and regeneration following injury.Keratin-14^(+)(K14^(+)) cells have been recognized as bona fide salivary gland stem/progen... Stem/progenitor cells are important for salivary gland development, homeostasis maintenance, and regeneration following injury.Keratin-14^(+)(K14^(+)) cells have been recognized as bona fide salivary gland stem/progenitor cells. However, K14 is also expressed in terminally differentiated myoepithelial cells;therefore, more accurate molecular markers for identifying salivary stem/progenitor cells are required. The intraflagellar transport(IFT) protein IFT140 is a core component of the IFT system that functions in signaling transduction through the primary cilia. It is reportedly expressed in mesenchymal stem cells and plays a role in bone formation. In this study, we demonstrated that IFT140 was intensively expressed in K14^(+)stem/progenitor cells during the developmental period and early regeneration stage following ligation-induced injuries in murine submandibular glands. In addition, we demonstrated that IFT140^(+)/K14^(+)could self-renew and differentiate into granular duct cells at the developmental stage in vivo. The conditional deletion of Ift140 from K14^(+)cells caused abnormal epithelial structure and function during salivary gland development and inhibited regeneration. IFT140 partly coordinated the function of K14^(+)stem/progenitor cells by modulating ciliary membrane trafficking. Our investigation identified a combined marker, IFT140^(+)/K14^(+), for salivary gland stem/progenitor cells and elucidated the essential role of IFT140 and cilia in regulating salivary stem/progenitor cell differentiation and gland regeneration. 展开更多
关键词 SALIVARY PROGENITOR INJURIES
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Three-dimensional conformal radiotherapy plus concurrent DICE chemotherapy for early-stage nasal-type natural killer/T-cell lymphoma of Waldeyer's ring: A single-institution study
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作者 ji zhou Daiyuan Ma +4 位作者 Yeqin zhou Xianfu Li Bangxian Tan Mi Liu Tao Ren 《Oncology and Translational Medicine》 CAS 2015年第4期181-185,共5页
Objective Nasal-type natural killer/T-cell lymphoma of Waldeyer's ring (WR-NK/TL) has different clinico- pathological characteristics from those of other subtypes of NK/T lymphoma; thus, the optimal treatment remai... Objective Nasal-type natural killer/T-cell lymphoma of Waldeyer's ring (WR-NK/TL) has different clinico- pathological characteristics from those of other subtypes of NK/T lymphoma; thus, the optimal treatment remains unclear. To find a more effective treatment model for WR-NK/TL, we conducted a single-center study of concurrent radiochemotherapy. Methods Forty-five patients with newly diagnosed stage IE to liE WR-NKTL were randomly divided into two groups. The 23 cases in the concurrent radiochemotherapy group were treated with three-dimensional conformal radiotherapy (48-52 Gy) and 2 courses of DICE (dexamethasone, ifosfamide, cisplatin, and etoposide) synchronous chemotherapy. The 22 cases in the radiotherapy group only received three-dimen- sional conformal radiotherapy (50-54 Gy). The primary end points were overall survival (OS), progression- free survival (PFS), and toxicity. Results The 1-, 3-, and 4-year OS and PFS rates were 95.5%, 65.6%, and 45.9%, and 86.4%, 56.0%, and 46.7% in the radiotherapy group, and 100%, 88.5%, and 88.5%, and 100%, 82.0%, and 73.8% in the concurrent radiochemotherapy group, respectively. The OS (P = 0.0477) and PFS rates (P = 0.0488) were higher in the concurrent radiochemotherapy group than in the radiotherapy group. The overall re- sponse rate was 100% in both the radiotherapy group [complete response (CR), 18 cases] and concurrent radiochemotherapy group (CR, 22 cases). The concurrent radiochemotherapy group had more severe side effects, especially grade 3 + 4 events, such as leukopenia, anorexia, and stomatitis. However, side effects benefiting from excellent oral care were endurable. Conclusion Radiotherapy plus concurrent DICE chemotherapy may be an effective and safe compre- hensive treatment for patients with WR-NKTL. 展开更多
关键词 nasal cavity NK/T-cell lymphoma prognosis radiotherapy CHEMOTHERAPY
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