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Chinese Optics Letters 2015年第12期13卷 58-61页

作者：李苏宇金明星 Institute of Atomic and molecular Physics Jilin University Jilin Provincial Key Laboratory of Applied Atomic and molecular spectroscopy(Jilin University)

The influence of group velocity dispersion（GVD） on the self-focusing of femtosecond laser pulses is investigated by numerically solving the extended nonlinear Schr？dinger equation. By introducing the GVD length LGVDinto the semi-empirical, self-focusing formula proposed by Marburger, a revised one is proposed, which can not only well explain the influence of GVD on the collapse distance, but also is in good agreement with the numerical results, making the self-focusing formula applicable for more cases.

关键词： Air Dispersions Focusing Group velocity dispersion Laser pulses Light velocity Nonlinear equations Ultrafast lasers

Absorption spectra and isotope shifts of the(2, 0),(3, 1), and(8, 5) bands of the A^2Π_u-X^2Σ_g^+ system of ^(15)N_2^+ in near infrared

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Chinese Physics B 2017年第10期26卷 165-168页

作者：叶佳汪海玲邓伦华 State Key Laboratory of Precision spectroscopy East China Normal University

The high-resolution absorption spectra of the （2,0）,（3,1）,and （8,5） bands of the A^2Π^u-X^2∑g^＋ system of ^15N2^＋ have been recorded by using velocity modulation spectroscopy technique in the near infrared *** rotational constants of the X^2∑g^＋ and A^2Πu states of ^15N2^＋ were derived from the spectroscopic *** isotope shifts of these bands of the A^2Πu-X^2∑g^＋ system of ^14N2^＋ and ^15N2^＋ were also analyzed and discussed.

关键词： molecular constants absorption spectrum isotope shift, ^15N2^+

Temporal Behaviours of Stimulated Rayleigh-Wing Scattering at Non- and Quasi-Equilibrium of Orientational Distribution

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Chinese Physics Letters 1995年第9期12卷 537-540页

作者： WANG Hezhou ZHENG Xiguang MAO Weidong YU Zhenxin GAO Zhaolan Institute for Laser and spectroscopy Zhongshan UniversityGuangzhou 510275

The temporal behaviours of stimulated Rayleigh-wing scattering,at quasi-equilibrium and non-equilibrium of the molecular orientational distributions,are reported in this *** experimental results also show the relaxati... 详细信息

关键词： equilibrium Rayleigh relaxation

NECAB family of neuronal calcium-binding proteins in health and disease

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Neural Regeneration Research 2025年第5期20卷 1236-1243页

作者： Diones Bueno Michael K.E.Schafer Sudena Wang Michael J.Schmeisser Axel Methner Institute for molecular Medicine University Medical Center of the Johannes Gutenberg-UniversityMainzGermany Department of Anesthesiology University Medical Center of the Johannes Gutenberg-UniversityMainzGermany Institute of Anatomy University Medical Center of the Johannes Gutenberg-UniversityMainzGermany

The N-terminal EF-hand calcium-binding proteins 1–3(NECAB1–3) constitute a family of predominantly neuronal proteins characterized by the presence of at least one EF-hand calcium-binding domain and a functionally less well characterized C-terminal antibiotic biosynthesis monooxygenase domain. All three family members were initially discovered due to their interactions with other proteins. NECAB1 associates with synaptotagmin-1, a critical neuronal protein involved in membrane trafficking and synaptic vesicle exocytosis. NECAB2 interacts with predominantly striatal G-protein-coupled receptors, while NECAB3 partners with amyloid-β A4 precursor protein-binding family A members 2 and 3, key regulators of amyloid-β production. This demonstrates the capacity of the family for interactions with various classes of proteins. NECAB proteins exhibit distinct subcellular localizations: NECAB1 is found in the nucleus and cytosol, NECAB2 resides in endosomes and the plasma membrane, and NECAB3 is present in the endoplasmic reticulum and Golgi apparatus. The antibiotic biosynthesis monooxygenase domain, an evolutionarily ancient component, is akin to atypical heme oxygenases in prokaryotes but is not wellcharacterized in vertebrates. Prokaryotic antibiotic biosynthesis monooxygenase domains typically form dimers, suggesting that calcium-mediated conformational changes in NECAB proteins may induce antibiotic biosynthesis monooxygenase domain dimerization, potentially activating some enzymatic properties. However, the substrate for this enzymatic activity remains uncertain. Alternatively, calcium-mediated conformational changes might influence protein interactions or the subcellular localization of NECAB proteins by controlling the availability of protein–protein interaction domains situated between the EF hands and the antibiotic biosynthesis monooxygenase domain. This review summarizes what is known about genomic organization, tissue expression, intracellular localization, interac

关键词： calcium EF hand mitochondria nervous system signal transduction

Cooling and trapping polar molecules in an electrostatic trap

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Chinese Physics B 2015年第5期24卷 318-322页

作者：王振霞顾振兴邓联忠印建平 State Key Laboratory of Precision spectroscopy East China Normal University

An electrostatic trap for polar molecules is proposed. Loading and trapping of polar molecules can be realized by applying different voltages to the two electrodes of the trap. For ND3 molecular beams centered at -10 m/s, a high loading efficiency of -67% can be obtained, as confirmed by our Monte Carlo simulations. The volume of our trap is as large as ,-3.6 cm3, suitable for study of the adiabatic cooling of trapped molecules. Our simulations indicate that trapped ND3 molecules can be cooled from -23.3 mK to 1.47 mK by reducing the trapping voltages on the electrodes from 50.0 kV to 1.00 kV.

关键词： trapping molecules cooling molecules Stark shift of molecules

Chirality recognition in concerted proton transfer process for prismatic water clusters

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Nano Research 2016年第9期9卷 2782-2795页

作者： Bo Wang Wanrun Jiang Yang Gao Boon K.Teo Zhigang Wang Institute of Atomic and molecular Physics Jilin UniversityChangchun 130012China Jilin Provincial Key Laboratory of Applied Atomic and molecular spectroscopy(Jilin University) Changchun 130012China College of Chemistry and molecular Engineering Peking UniversityBeijing 100871China College of Chemistry and Chemical Engineering Xiamen UniversityXiamen 361005China Beijing Computational Science Research Center Beijing 100084China

Proton transfer and chiral conversion via hydrogen bonds (HBs) are important processes in applications such as chiral recognition, enzymatic catalysis, and drug preparation. Herein, we investigate the chiral conversion and interlayer recognition, via concerted intralayer proton transfer (CIPT) processes, of small prismatic water clusters, in the form of bilayer n−membered water rings (BnWRs, n = 4, 5, 6). Density functional theory (DFT) calculations show that despite the small energy variations between the initial and final states of the clusters of less than 0.3 kcal·mol−1, the vibrational circular dichroism (VCD) spectrum provides clear chiral recognition peaks in the range of 3,000 to 3,500 cm−1. The vibrational modes in this region correspond to stretching of intralayer HBs, which produces strong signals in the infrared (IR) and Raman spectra. The electronic circular dichroism (ECD) spectrum also reveals obvious chiroptical characteristics. The molecular orbitals involved in the interlayer interaction are dominated by O 2p atomic orbitals; the energy of these orbitals increased by up to 0.1 eV as a result of the CIPT processes, indicating corresponding recognition between monolayer water clusters. In addition, isotopic substitution by deuterium in the BnWRs results in characteristic peaks in the VCD spectra that can be used as fingerprints in the identification of the chiral structures. Our findings provide new insights into the mechanism of chiral recognition in small prismatic water clusters at the atomic level as well as incentives for future experimental studies. [Figure not available: see fulltext.] © 2016, Tsinghua University Press and Springer-Verlag Berlin Heidelberg.

关键词： water cluster chirality proton transfer circular dichroism spectrum density functional theory calculation

Third-Order Optical Nonlinearity in Novel Porphyrin Dimers

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Chinese Physics Letters 2008年第12期25卷 4292-4295页

作者：裴松皓赵大鹏张巍郑文琦王杏乔彭慰先石光宋瑛林 Key Laboratory of Coherent Light Atomic and Molecular Spectroscopy Ministry of Education Jilin University Changchun 130023 College of Chemistry Jilin University Changchun 130023 School of Physical Science and Technology Suzhou University Suzhou 215006

We investigate the third-order optical nonlinearities in four novel porphyrin dimers （dimers A to D） and a monomeric porphyrin H2 CPTPP measured by using the single-beam z-scan technique with a pulsed Q-switched Nd：YAG nanosecond laser at 532nm. All the samples show strong excited state absorption （ESA） and high value of Х^（3） in the ns domain at this wavelength. We perform a comparison between dimer A and its monomer H2 CPTPP in their third-order optical nonlinearity, and discuss the relationships between the values of Х^（3） and the different bridging groups for all the dimers.

关键词： field emission molybdenum dioxide enhancement factor

Analysis of sampled fiber Bragg gratings polarization-maintaining fiber

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Chinese Optics Letters 2008年第7期6卷 479-482页

作者：雷永庆韦珏徐晓峰李亚娟 Key Laboratory of Coherent Light Atomic and Molecular SpectroscopyCollege of PhysicsJilin UniversityChangchun 130023

A novel type of sampled fiber Bragg gratings （FBGs） written in polarization-maintaining fiber （PMF） is proposed. The reflection spectrum, time delay, and group velocity dispersion （GVD） of the gratings are analyzed. In addition, the reflection spectrum is optimized by apodization. The scheme of multi-wavelength output based on the gratings is proposed, which could be used as a multi-wavelength polarization filter in the density wavelength division multiplexed （DWDM） system.

关键词： Computer networks Electromagnetic waves Fiber optic sensors Fiber optics Fibers Light polarization Multiplexing Optical filters Polarization Reflection

Diversity, frequency, and geographic distribution of facultative bacterial endosymbionts in introduced aphid pests

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Insect Science 2017年第3期24卷 511-521页

作者： Daniela A. Sepulvedat Francisca Zepeda-Paulo Claudio C. Ramfrez Bias Lavandero Christian C. Figueroa Facultad de Ciencias Agrarias Universidad de Talca Instituto de Ciencias BiolSgicas Universidad de Talca Millennium nucleus Centre in molecular Ecology and Evolutionary Applications in the Agroecosystems Universidad de Talca 2 Norte 685 Talca Chile

Facultative bacterial endosymbionts in insects have been under intense study during the last years. Endosymbionts can modify the insect＇s phenotype, conferring adap- tive advantages under environmental stress. This seems particularly relevant for a group of worldwide agricultural aphid pests, because endosymbionts modify key fitness-related traits, including host plant use, protection against natural enemies and heat tolerance. Aimed to understand the role of facultative endosymbionts on the success of introduced aphid pests, the distribution and abundance of 5 facultative endosymbionts （Hamiltonella defensa, Regiella insecticola, Serratia symbiotica, Rickettsia and Spiroplasma） were stud- ied and compared in 4 cereal aphids （Sitobion avenae, Diuraphis noxia, Metopolophium dirhodum and Schizaphis graminium） and in the pea aphid Acyrthosiphon pisum complex from 2 agroclimatic zones in Chile. Overall, infections with faeultative endosymbionts exhibited a highly variable and characteristic pattern depending on the aphid species/host race and geographic zone, which could explain the success of aphid pest populations after their introduction. While S. symbiotica and H. defensa were the most frequent endosym- bionts carried by the A. pisum pea-race and A. pisum alfalfa-race aphids, respectively, the most frequent facultative endosymbiont carried by all cereal aphids was R. insecticola. Interestingly, a highly variable composition of endosymbionts carried by S. avenae was also observed between agroclimatic zones, suggesting that endosymbionts are responding differentially to abiotic variables （temperature and precipitations）. In addition, our findings constitute the first report of bacterial endosymbionts in cereal aphid species not screened before, and also the first report of aphid endosymbionts in Chile.

关键词： cereal aphids facultative bacterial endosymbionts grain aphid introduced aphids pea aphid

Single-cell and spatial omics:exploring hypothalamic heterogeneity

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Neural Regeneration Research 2025年第6期20卷 1525-1540页

作者： Muhammad Junaid Eun Jeong Lee Su Bin Lim Department of Biochemistry&molecular Biology Ajou University School of MedicineSuwonSouth Korea Department of Biomedical Sciences Graduate School of Ajou UniversitySuwonSouth Korea Department of Brain Science Ajou University School of MedicineSuwonSouth Korea

Elucidating the complex dynamic cellular organization in the hypothalamus is critical for understanding its role in coordinating fundamental body functions. Over the past decade, single-cell and spatial omics technologies have significantly evolved, overcoming initial technical challenges in capturing and analyzing individual cells. These high-throughput omics technologies now offer a remarkable opportunity to comprehend the complex spatiotemporal patterns of transcriptional diversity and cell-type characteristics across the entire hypothalamus. Current single-cell and single-nucleus RNA sequencing methods comprehensively quantify gene expression by exploring distinct phenotypes across various subregions of the hypothalamus. However, single-cell/single-nucleus RNA sequencing requires isolating the cell/nuclei from the tissue, potentially resulting in the loss of spatial information concerning neuronal networks. Spatial transcriptomics methods, by bypassing the cell dissociation, can elucidate the intricate spatial organization of neural networks through their imaging and sequencing technologies. In this review, we highlight the applicative value of single-cell and spatial transcriptomics in exploring the complex molecular-genetic diversity of hypothalamic cell types, driven by recent high-throughput achievements.

关键词： cellular diversity hypothalamus multi-omics single-cell transcriptomics spatial transcriptomics