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Controlling the Shape of a Cold Atom Cloud in a Cylindrical Cavity

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Chinese Physics Letters 2013年第6期30卷 90-93页

作者： meng yan-ling CHENG Hua-Dong ZHENG Ben-Chang WANG Xu-Cheng XIAO ling LIU Liang Key Laboratory of Quantum Optics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800 Key Laboratory of Atomic Frequency Standards Wuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhan 430071

This study presents an experiment on diffuse light cooling of atoms in a cylindrical *** focus on the controlling of the shape of the atom cloud by placing the cooling beams in appropriate *** Gauss-like shape of the atomic cloud is *** number of cold atoms detected in the cavity is increased,thereby improving the signal-to-noise ratio of the clock signal.

关键词： cavity. thereby cylindrical

Development of an Integrating Sphere Cold Atom Clock

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Chinese Physics Letters 2013年第12期30卷 30-32页

作者： ZHENG Ben-Chang CHENG Hua-Dong meng yan-ling XIAO ling WAN Jin-Yin LIU Liang Key Laboratory of Quantum Optics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800 Key Laboratory of Atomic Frequency Standards Wuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhan 430071

The Ramsey fringes with a linewidth of 45 Hz and a signal-to-noise ratio of 120 are demonstrated for a integrating sphere atom *** cycle time of the atom clock is reduced to 80 ms with the help of a pulsed cooling ***... 详细信息

关键词： method integrating clock

Measurement of Spatial Distribution of Cold Atoms in an Integrating Sphere

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Chinese Physics Letters 2012年第2期29卷 79-82页

作者： WANG Xu-Cheng CHENG Hua-Dong XIAO ling ZHENG Ben-Chang meng yan-ling LIU Liang WANG Yu-Zhu Key Laboratory of Quantum Optics and Center of Cold Atom Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800

We present an experiment on the measurement of the spatial distribution of cold atoms in a ceramic *** atoms are first cooled by diffusing light produced by multiple scattering of laser light at the inner surface of the *** inhomogeneous magnetic field is applied after the atoms are cooled by using a pair of anti-Helmholtz coils,and thus the shift of atomic magnetic sub-levels is *** move the anti-Helmholtz coils point by point while keeping the probe laser beam resonant with the cold atoms at zero magnetic *** number of cold atoms at different positions can be extracted by detecting the absorption to the probe *** density of the cold atoms in the cell is measured in two dimensions perpendicular and parallel to the tube connecting to the vacuum system,*** results show that at the center of the cell,fewer atoms exist due to the leakage of diffuse light into the hole connecting to the vacuum *** method we developed is used to detect cold atoms in a region where imaging is impossible.

关键词： field connecting vacuum

种植业生产技术综合效益评价指标和方法的研究进展

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河北农业科学 2024年第3期28卷 104-108页

作者：张涵赵文庆赵宇张锦添孟艳玲李顺国刘猛河北工程大学园林与生态工程学院河北邯郸056107 河北省农林科学院谷子研究所/农业农村部特色杂粮遗传改良与利用重点实验室(部省共建)/河北省杂粮研究重点实验室河北石家庄050035

种植业生产技术经济评价是对种植业生产过程中各项指标进行综合效益的评估,从而确定种植业生产技术的综合效益水平。为了全面了解和评价种植业生产技术的发展情况,为决策者提供依据及推动农业可持续发展,采用文献资料法及归纳总结法,对... 详细信息

种植业生产技术经济评价是对种植业生产过程中各项指标进行综合效益的评估,从而确定种植业生产技术的综合效益水平。为了全面了解和评价种植业生产技术的发展情况,为决策者提供依据及推动农业可持续发展,采用文献资料法及归纳总结法,对种植业生产技术综合效益评价的研究现状、评价指标和方法进行系统总结和归纳,为种植业生产技术综合效益评价的深入研究提供参考和指导。

关键词：种植业生产技术综合效益评价指标

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Adaptive admittance tracking control for interactive robot with prescribed performance

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Journal of Systems Engineering and Electronics 2024年第2期35卷 444-450页

作者： meng Qingrui LIN yan School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100190China College of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao 266590China

An adaptive control approach is presented in this paper for tracking desired trajectories in interactive manipulators. The controller design incorporates prescribed performance functions (PPFs) to improve dynamic performance. Notably, the performance of the output error is confined in an envelope characterized by exponential convergence, leading to convergence to zero. This feature ensures a prompt response from admittance control and establishes a reliable safety framework for interactions. Simulation results provide practical insights,demonstrating the viability of the control scheme proposed in this paper.

关键词： prescribed performance admittance control adaptive control robots

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A CRISPR/RfxC as13d-mediated strategy for efficient RNA knockdown in mouse embryonic development

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Science China Life Sciences 2024年

作者： Lin Zhang Shi-meng Cao Hao Wu meng yan Jinsong Li ling-ling Chen State Key Laboratory of Cell Biology Shanghai Key Laboratory of Molecular Andrology Shanghai Institute of Biochemistry and Cell Biology Center for Excellence in Molecular Cell Science Chinese Academy of Sciences University of Chinese Academy of Sciences Key Laboratory of RNA Innovation Science and Engineering CAS Center for Excellence in Molecular Cell Science Shanghai Institute of Biochemistry and Cell Biology University of Chinese Academy of Sciences Chinese Academy of Sciences Key Laboratory of Systems Health Science of Zhejiang Province School of Life Science Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences School of Life Science and Technology ShanghaiTech University New Cornerstone Science Laboratory Shenzhen

The growing variety of RNA classes, such as mRNAs, lncRNAs, and circRNAs, plays pivotal roles in both developmental processes and various pathophysiological conditions. Nonetheless, our comprehension of RNA functions in live organisms remains limited due to the absence of durable and effective strategies for directly influencing RNA levels. In this study, we combined the CRISPR-RfxCas13d system with spermlike stem cell-mediated semi-cloning techniques, which enabled the suppressed expression of different RNA species. This approach was employed to interfere with the expression of three types of RNA molecules: Sfmbt2 mRNA, Fendrr lncRNA, and circMan1a2(2,3,4,5,6). The results confirmed the critical roles of these RNAs in embryonic development, as their loss led to observable phenotypes, including embryonic lethality, delayed embryonic development, and embryo resorption. In summary, our methodology offers a potent toolkit for silencing specific RNA targets in living organisms without introducing genetic alterations.

关键词：

Controlling the Reactivity of IBA-N_(3)by Switching Halogen Salts:Providing a Universal Strategy for Haloazidation of Alkenes

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Chinese Journal of Chemistry 2024年第16期42卷 1839-1845页

作者： Chen-Xi Xia Xin-Lei Sun Jinfeng Zhang Yue Ren yan Yu Kuai Wang ling-Guo meng Key Laboratory of Green and Precise Synthetic Chemistry and Applications Ministry of Education/School of Chemistry and Materials ScienceHuaibeiNormal UniversityHuaibeiAnhui 235000China

Although various routes have been reported for haloazidation,unavoidable problems exist,such as environmentally unfriendly monomer halogen,the need for in situ generation of unstable halogen azides(XN3),applicability to one type of haloazidation and inability to precisely control ***,we developed a universal strategy for haloazidation of alkenes through controlling the reactivity of IBA-N_(3) by switching halogen salts,allowing for the synthesis of a diversity of halogen azide *** studies have shown that by tuning the reactivity of IBA-N_(3) via switching halogen salts,different intermediates can be controllably produced to achieve regioselectivityand chemoselectivity in thehaloazidationof alkenes.

关键词： Haloazidation Alkene IBA-N_(3) Halogen salts Difunctionalization Selectivity Radicals Synthetic methods

Success of susceptibility-guided eradication of Helicobacter pylori in a region with high secondary clarithromycin and levofloxacin resistance rates

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World Journal of Gastroenterology 2024年第2期30卷 184-195页

作者： yan-meng Wang Mo-Ye Chen Jing Chen Xin-He Zhang yan Feng Yu-Xi Han Yi-ling Li Department of Gastroenterology The First Affiliated Hospital of China Medical UniversityShenyang 110000Liaoning ProvinceChina Key Laboratory of Cancer Etiology and Prevention in Liaoning Education Department The First Hospital of China Medical UniversityShenyang 110000Liaoning ProvinceChina

BACKGROUND Resistance to clarithromycin(CLA)and levofloxacin(LFX)of Helicobacter pylori(***)is increasing in severity,and successful eradication is ***,the eradication success rate has greatly declined,leaving a large number of patients with previous treatment *** To investigate secondary resistance rates,explore risk factors for antibiotic resistance,and assess the efficacy of susceptibility-guided *** We recruited 154 subjects positive for Urea Breath Test who attended The First Affiliated Hospital of China Medical University between July 2022 and April *** underwent a string test after an overnight *** gastric juice was obtained and transferred to vials containing storage ***,DNA extraction and the specific DNA amplification were performed using quantitative polymerase chain reaction(qPCR).Demographic information was also analyzed as part of the *** on these results,the participants were administered susceptibility-guided *** was compared with that of the empiric treatment *** A total of 132 individuals tested positive for the *** ureA gene by qPCR *** resistance rate reached a high level of 82.6%(n=109),LFX resistance rate was 69.7%(n=92)and dual resistance was 62.1%(n=82).Gastric symptoms[odds ratio(OR)=2.782;95%confidence interval(95%CI):1.076-7.194;P=0.035]and rural residence(OR=5.152;95%CI:1.407-18.861;P=0.013)were independent risk factors for secondary resistance to CLA and LFX,respectively.A total of 102 and 100 individuals received susceptibility-guided therapies and empiric treatment,*** antibiotic susceptibility-guided treatment and empiric treatment groups achieved successful eradication rates of 75.5%(77/102)and 59.0%(59/411)by the intention-to-treat(ITT)analysis and 90.6%(77/85)and 70.2%(59/84)by the per-protocol(PP)analysis,*** eradication rates of these two treatment strategies were significantly

关键词： Helicobacter pylori Antibiotic resistance Clarithromycin Levofloxacin String-test Susceptibility-guided therapy Eradication rate

NLRP3-mediated autophagy dysfunction links gut microbiota dysbiosis to tau pathology in chronic sleep deprivation

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Zoological Research 2024年第4期45卷 857-874页

作者： Na Zhao Xiu Chen Qiu-Gu Chen Xue-Ting Liu Fan Geng meng-meng Zhu Fu-ling yan Zhi-Jun Zhang Qing-Guo Ren Department of Neurology School of MedicineSoutheast UniversityNanjingJiangsu 210009China Department of Neurology Affiliated Zhongda HospitalSoutheast UniversityNanjingJiangsu 210009China

Emerging evidence indicates that sleep deprivation(SD)can lead to Alzheimer’s disease(AD)-related pathological changes and cognitive ***,the underlying mechanisms remain *** the present study,we identified the existence of a microbiota-gut-brain axis in cognitive deficits resulting from chronic SD and revealed a potential pathway by which gut microbiota affects cognitive functioning in chronic *** findings demonstrated that chronic SD in mice not only led to cognitive decline but also induced gut microbiota dysbiosis,elevated NLRP3 inflammasome expression,GSK-3βactivation,autophagy dysfunction,and tau hyperphosphorylation in the *** with the“SD microbiota”replicated the pathological and behavioral abnormalities observed in chronic sleep-deprived ***,both the deletion of NLRP3 in NLRP3-/-mice and specific knockdown of NLRP3 in the hippocampus restored autophagic flux,suppressed tau hyperphosphorylation,and ameliorated cognitive deficits induced by chronic SD,while GSK-3βactivity was not regulated by the NLRP3 inflammasome in chronic ***,deletion of NLRP3 reversed NLRP3 inflammasome activation,autophagy deficits,and tau hyperphosphorylation induced by GSK-3βactivation in primary hippocampal neurons,suggesting that GSK-3β,as a regulator of NLRP3-mediated autophagy dysfunction,plays a significant role in promoting tau ***,gut microbiota dysbiosis was identified as a contributor to chronic SD-induced tau pathology via NLRP3-mediated autophagy dysfunction,ultimately leading to cognitive ***,these findings highlight GSK-3βas a regulator of NLRP3-mediated autophagy dysfunction,playing a critical role in promoting tau hyperphosphorylation.

关键词： Chronic sleep deprivation Tau pathology NLRP3 inflammasome Autophagy GSK-3β Microbiota-gut-brain axis

维普期刊数据库