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Polyaspers A and B,the First Ergosterol-Polyether Adducts with Unprecedented 6/6/6/5/5/6/6/6/6 Nonacyclic Architecture from Aspergillus ***507

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Chinese Journal of Chemistry 2024年第7期42卷 743-751页

作者： Hong Hu Lanqin Li Zhengyi Shi Xueqi Lan Yeting zhang Xinye Huang Xincai Hao Qun Zhou Weiguang Sun Changxing Qi yonghui zhang Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei 430030China Institute of Organ Transplantation Tongji HospitalTongji Medical CollegeHuazhong University of Science and Technology Key Laboratory of Organ TransplantationMinistry of EducationNHC Key Laboratory of Organ TransplantationKey Laboratory of Organ TransplantationChinese Academy of Medical SciencesWuhanHubei 430030China Hubei Key Laboratory of Wudang Local Chinese Medicine Research Hubei Engineering Technology Center for Comprehensive Utilization of Medicinal PlantsCollege of PharmacyHubei University of MedicineShiyanHubei 442000China

Psoriasis is a chronic immune-mediated inflammatory skin disease and the TNF-αis an important therapeutic target of this *** our continuous study of bioactive natural products from fungi,the first ergosterol-polyether adducts,polyaspers A(1)and B(2),along with two known ergosterols,(36,5α,6α,22E)-5,6-epoxy-3-hydroxyergosta-8,22-dien-7-one(3)and calvasterol B(4),were iso-lated from Aspergillus *** elucidation was accomplished by extensive spectroscopic analysis and single-crystal X-ray diffraction *** A and B possessing an unequalled 6/6/6/5/5/6/6/6/6 nonacyclic system,and their biosynthetic path-ways were proposed to include intermolecular cyclization and Diels-Alder *** screen of these isolates showed that 1-3 could improve the cell viability in an actinomycin D/TNF-αinduced L929 cells death model,with the EC50 values of 49.85,46.75 and 4.99μmol/L,respectively,and the activity of 3 was even comparable with that of the positive control *** bioactive investigations discovered 3 could suppress the inflammatory response simulated with TNF-αin HaCaT *** an imiquimod-induced psoriasis murine model,3 significantly restrained the development of psoriasis symptoms and reduced the expression of IL-17 and IL-23,presenting an anti-psoriatic *** such,those ergosterol derivatives,might serve as lead compounds for the development of novel TNF-αinhibitory agents in the clinical treatment of psoriasis.

关键词： Psoriasis Aspergillus sp.TJ507 TNF-α Ergosterol-polyether adducts Inflammatory skin disease

Ten ring-B aromatized ergosterols from Aspergillus spectabilis

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Chinese Journal of Natural Medicines 2024年第7期22卷 654-662页

作者： WEI Mengsha SUN Weiguang LIU Linlin LI Yongqi LI Lanqin LI Qin CHEN Yu GUO Jieru GU Lianghu ZHU Hucheng CHEN Chunmei zhang yonghui Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation School of PharmacyTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Tongji Hospital Affiliated to Tongji Medical College Huazhong University of Science and TechnologyWuhan 430030China

Spectasterols F−O(1−10),ten interesting ergosterols with an aromatized B ring,were obtained from Aspergillus *** structures and absolute configurations were determined using a combination of high-resolution electrospray ionization mass spectrometry(HR-ESI-MS),nuclear magnetic resonance(NMR)spectroscopy,single-crystal X-ray diffraction analyses,and electronic circular dichroism(ECD)***,these aromatic ergosterols feature versatile side ***,compound aromatic ergosterols featured versatile side chains,and compound 4 is an unusual C23 ergosterol characterized by a shorter side chain due to oxidative cleavage between C-23 and *** compounds were evaluated for their neuroprotective activities,with compound 8 showing a dose-dependent ability to reduce apoptosis and protect mitochondrial function in glutamate-induced SH-SY5Y cells.

关键词： Steroids Aspergillus spectabilis Aromatic ergosterols Neuroprotective activities Structure elucidation

Strain-enhanced polarization sensitivity in β-GaOphotodetector

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Science China(Physics,Mechanics & Astronomy) 2024年

作者： yonghui zhang Huili Liang Fei Xing Qiqian Gao Yu Feng Yuping Sun Zengxia Mei Songshan Lake Materials Laboratory Institute of Physics Chinese Academy of Sciences School of Physics and Optoelectronic Engineering Shandong University of Technology

Polarization-sensitive photodetection and imaging have great application value in fields such as polarization division multiplexing optical communication,remote sensing,near-field imaging and military *** a high polarization ratio has always been the research hotspot in polarization-sensitive *** this paper,we report a compression strain enhanced polarization ratio in β-gallium oxide (β-Ga2O3) single crystal flake.A rigorous crystallographic analysis confirmed its high crystalline quality and ***-resolved polarization Raman spectroscopy (ARPRS) was adopted to study the anisotropy of its optical *** ARPRS measurements and theoretical calculation consistently demonstrate the strong optical anisotropy in the high-quality β-Ga2O3flake.A polarization ratio of 0.96 was obtained in the flat β-***,mechanical strain of ±0.7% was introduced into β-*** increased polarization ratio of 0.98 was achieved in the case of 0.7% compression strain,which is,to the best of our knowledge,the highest value for UVC polarization-sensitive *** corresponds to an improved polarization rejection ratio of *** work proposed a new path towards improving polarization sensitivity by applying strain engineering in the active material.

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Low-Voltage IGZO Field-Effect Ultraviolet Photodiode

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Chinese Physics Letters 2024年第6期41卷 156-161,I0001-I0003页

作者：宋双梁会力霍文星张广张永晖王绩伟梅增霞 Songshan Lake Materials Laboratory Dongguan 523808China Institute of Physics Chinese Academy of SciencesBeijing 100190China College of Physics Liaoning UniversityShenyang 110036China Department of Instruments Science and Technology School of Precision Instrument and Opto-electronics EngineeringTianjin UniversityTianjin 300072China National Key Laboratory of Scattering and Radiation Beijing 100039China School of Physics and Optoelectronic Engineering Shandong University of TechnologyZibo 255000China

In the era of Internet of Things(Io Ts),an energy-efficient ultraviolet(UV)photodetector(PD)is highly desirable considering the massive usage scenarios such as environmental sterilization,fire alarm and corona discharge *** far,common self-powered UV PDs are mainly based on metal-semiconductor heterostructures or p–n heterojunctions,where the limited intrinsic built-in electric field restricts further enhancement of the *** this work,an extremely low-voltage field-effect UV PD is proposed using a gatedrain shorted amorphous IGZO(a-IGZO)thin film transistor(TFT)architecture.A combined investigation of the experimental measurements and technology computer-aided design(TCAD)simulations suggests that the reverse current(ⅠR)of field-effect diode(FED)is highly related with the threshold voltage(Vth)of the parental TFT,implying an enhancement-mode TFT is preferable to fabricate the field-effect UV PD with low dark *** by a low bias of-0.1 V,decent UV response has been realized including large UV/visible(R_(300)/R_(550))rejection ratio(1.9×10^(3)),low dark current(1.15×10^(-12)A)as well as high photo-to-dark current ratio(PDCR,~10^(3))and responsivity(1.89 A/W).This field-effect photodiode provides a new platform to construct UV PDs with well-balanced photoresponse performance at a low bias,which is attractive for designs of large-scale smart sensor networks with high energy efficiency.

关键词： IGZO attractive ultraviolet

基于络病理论探讨椎基底动脉延长扩张症与脑小血管病的共病机制

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中国实验方剂学杂志 2024年第13期30卷 192-201页

作者：张永辉张道培河南中医药大学第一临床医学院郑州450000 河南中医药大学第一附属医院郑州450000

椎基底动脉延长扩张症(VBD)共病脑小血管病(CSVD)增加患者的不良预后,阐释二者共病的机制有助于探索有效的治疗策略。血管在解剖形态、生理病理上与中医学“络脉”具有同一性,因此以络病理论为切入点,结合中西医对二者认识的病机理论和... 详细信息

椎基底动脉延长扩张症(VBD)共病脑小血管病(CSVD)增加患者的不良预后,阐释二者共病的机制有助于探索有效的治疗策略。血管在解剖形态、生理病理上与中医学“络脉”具有同一性,因此以络病理论为切入点,结合中西医对二者认识的病机理论和研究进展,提出二者病位均在脑络,属本虚标实。共病的主要病机以元气亏虚,脑络空虚为本,对应现代医学的内皮细胞和神经-内分泌-免疫网络功能障碍;以脑络瘀阻,脑络闭塞,毒损脑络为标,对应现代医学的脑血管动脉粥样硬化、血流动力学改变、低灌注和毒性代谢产物损伤脑白质。基于络病理论,探讨二者共同的病机,可望探索建立中医药治疗的理法方药,改善患者的临床预后。

关键词：络病理论络脉椎基底动脉延长扩张症脑小血管病

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Visible-to-near-infrared photodetectors based on SnS/SnSe_(2)and SnSe/SnSe_(2)p−n heterostructures with a fast response speed and high normalized detectivity

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Journal of Semiconductors 2024年第3期45卷 76-83页

作者： Xinfa Zhu Weishuai Duan Xiancheng Meng Xiyu Jia yonghui zhang Pengyu Zhou Mengjun Wang Hongxing Zheng Chao Fan School of Electronic and Information Engineering Hebei University of TechnologyTianjin 300401China School of Science Northeast Electric Power UniversityJilin 132012China

The emergent two-dimensional(2D)material,tin diselenide(SnSe_(2)),has garnered significant consideration for its potential in image capturing systems,optical communication,and optoelectronic ***,SnSe_(2)-based photodetection faces obstacles,including slow response speed and low normalized *** this work,photodetectors based on SnS/SnSe_(2)and SnSe/SnSe_(2)p−n heterostructures have been implemented through a polydimethylsiloxane(PDMS)−assisted transfer *** photodetectors demonstrate broad-spectrum photoresponse within the 405 to 850 nm wavelength *** photodetector based on the SnS/SnSe_(2)heterostructure exhibits a significant responsivity of 4.99×10^(3)A∙W^(−1),normalized detectivity of 5.80×10^(12)cm∙Hz^(1/2)∙W^(−1),and fast response time of 3.13 ms,respectively,owing to the built-in electric ***,the highest values of responsivity,normalized detectivity,and response time for the photodetector based on the SnSe/SnSe_(2)heterostructure are 5.91×10^(3)A∙W^(−1),7.03×10^(12)cm∙Hz^(1/2)∙W−1,and 4.74 ms,*** their photodetection performances transcend those of photodetectors based on individual SnSe_(2),SnS,SnSe,and other commonly used 2D *** work has demonstrated an effective strategy to improve the performance of SnSe_(2)-based photodetectors and paves the way for their future commercialization.

关键词： two-dimensional materials tin diselenide heterostructures broad-spectrum photodetectors

奥运奖牌可以被预测吗?——基于可解释机器学习视角

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上海体育大学学报 2024年第4期48卷 26-36页

作者：石慧敏章东迎章永辉中国人民大学经济学院北京100872

基于1992-2021年夏季奥运会的分项目成绩大数据,使用随机森林模型评估不同项目金牌和奖牌的可预测性,发现各项目存在较大的差异:对奖牌而言,可预测性最强的是乒乓球、羽毛球和游泳,而最弱的是水球、现代五项和排球。基于可解释机器学习... 详细信息

基于1992-2021年夏季奥运会的分项目成绩大数据,使用随机森林模型评估不同项目金牌和奖牌的可预测性,发现各项目存在较大的差异:对奖牌而言,可预测性最强的是乒乓球、羽毛球和游泳,而最弱的是水球、现代五项和排球。基于可解释机器学习方法挖掘社会经济因素对奥运奖牌的影响发现:(1)对同一个项目而言,女子项目的可预测准确性普遍高于男子项目;(2)代表队所在地区的人口规模、人均GDP、是否为主办国等因素对奖牌总数具有一定影响;(3)在特定项目上,代表队的传统优势(如中国的乒乓球、美国的田径等)对奖牌预测具有较大影响。

关键词：奥运奖牌机器学习特征重要性 SHAP方法 Shapley值

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增益分布对GaN基蓝光微盘激光器模式分布和发光功率的影响

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红外与激光工程 2024年第1期53卷 136-143页

作者：许湘钰刘召强贾童楚春双张勇辉张紫辉河北工业大学电子信息工程学院天津300401 河北工业大学天津市电子材料与器件重点实验室天津300401 河北工业大学河北省先进激光技术与装备重点实验室天津300401

通过FDTD仿真模拟计算,文中系统地研究了电流阻挡作用对GaN基蓝光激光器增益分布和光学性能的影响,发现回音壁激光模式主要在靠近微盘边缘1.5个波长范围谐振,因此,如果电流阻挡层面积太小,无法最大化减小激光器电流阈值;如果面积太大,... 详细信息

通过FDTD仿真模拟计算,文中系统地研究了电流阻挡作用对GaN基蓝光激光器增益分布和光学性能的影响,发现回音壁激光模式主要在靠近微盘边缘1.5个波长范围谐振,因此,如果电流阻挡层面积太小,无法最大化减小激光器电流阈值;如果面积太大,回音壁激光模式与无增益区存在耦合效应,从而减少激光功率。另外,随着无增益区域向微盘边缘发生偏移,各个激光模式输出的峰值功率均下降,其中二阶模式峰值功率比一阶模式下降得更加显著,这主要是由于二阶模式分布范围更接近微盘中心区域。同时,进一步发现如果在微盘激光器的仿真模型中引入侧壁缺陷,则将导致边缘无法形成增益区,相比于二阶模式而言,一阶模式的发光功率随侧壁缺陷区域增加而下降的幅度更为显著,这主要是由于一阶模式分布范围更接近微盘边缘。

关键词：激光器微盘增益 FDTD

城市轨道交通站台区域精确停车窗设置方案研究

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铁道通信信号 2024年第6期60卷 57-61页

作者：张永会卡斯柯信号有限公司上海200071

随着城市轨道交通高效率、高密度,以及灵活编组混跑等运营组织需求的提出,为更好地适应潮汐客流分布不均衡的特点,结合不同编组列车共线运行时的不同停车策略,阐述城市轨道交通中站台区域精确停车窗设置需考虑的因素及设置方案、精确停... 详细信息

随着城市轨道交通高效率、高密度,以及灵活编组混跑等运营组织需求的提出,为更好地适应潮汐客流分布不均衡的特点,结合不同编组列车共线运行时的不同停车策略,阐述城市轨道交通中站台区域精确停车窗设置需考虑的因素及设置方案、精确停车窗计算原理等;针对多编组列车混跑,提出站台头端对齐、尾端对齐、以车站站台中心对齐等不同停车策略下的精确停车窗匹配设计方案;同时,为尽可能提高列车停站时的开门效率和停车窗设置的灵活性,在确保满足安全开关门要求的前提下,提出额外增加停车误差容忍余量的精确停车窗优化设计方案,可为多编组混跑项目的站台区域精确停车窗设计提供参考。

关键词：城市轨道交通潮汐客流灵活编组列车混跑精确停车窗站台区域站台端头门