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基于二维磁光阱的增强型^(199)Hg冷原子团制备

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物理学报 2024年第1期73卷 140-148页

作者：余泽鑫刘琪鑫孙剑芳徐震中国科学院上海光学精密机械研究所量子光学重点实验室上海201800 中国科学院大学北京100049

在精密测量领域中,高效地制备冷原子团具有重要的意义.在光晶格钟里,缩短冷原子团的制备时间可以降低Dick噪声,从而提高光晶格钟的稳定性.本文采用二维磁光阱加推送光的构型提高了三维磁光阱在超高真空环境中的装载率,并通过压缩磁光阱... 详细信息

在精密测量领域中,高效地制备冷原子团具有重要的意义.在光晶格钟里,缩短冷原子团的制备时间可以降低Dick噪声,从而提高光晶格钟的稳定性.本文采用二维磁光阱加推送光的构型提高了三维磁光阱在超高真空环境中的装载率,并通过压缩磁光阱技术降低了原子团温度,实现了用于^(199)Hg光晶格钟的增强型冷原子团制备.实验上通过优化三维和二维磁光阱的失谐量和磁场梯度以及推送光的失谐量和功率等参数,将三维磁光阱的^(199)Hg冷原子装载率增强了51倍,提升至3.1×10^(5)s^(–1),然后使用压缩磁光阱技术将^(199)Hg冷原子团的温度降低至45μK,低于多普勒冷却理论温度.这种基于二维磁光阱的增强型冷原子团制备可在超真空环境下实现对三维磁光阱装载率的高增益,有效地缩短了冷原子团的制备时间,同时也降低了原子团的温度,有利于提高光晶格的转移效率,为其他冷原子实验中冷汞原子团制备提供了有效方案.

关键词：汞原子光晶格钟激光冷却二维磁光阱

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Deciphering the population structure and genetic basis of growth traits from whole-genome resequencing of the leopard coral grouper(Plectropomus leopardus)

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Zoological Research 2024年第2期45卷 329-340页

作者： Shao-Xuan Wu Qi-Fan Zeng Wen-Tao Han Meng-Ya Wang Hui Ding Ming-Xuan Teng Ming-Yi Wang Pei-Yu Li xin Gao zhen.Min Bao Bo Wang Jing-Jie Hu MOE Key Laboratory of Marine Genetics and Breeding College of Marine Life Sciences/Key Laboratory of Tropical Aquatic Germplasm of Hainan ProvinceSanya Oceanographic InstitutionOcean University of ChinaQingdaoShandong/SanyaHainan 266100/572025China Hainan Seed Industry Laboratory SanyaHainan 572025China Southern Marine Science and Engineer Guangdong Laboratory GuangzhouGuangdong 511458China

The leopard coral grouper(Plectropomus leopardus)is a species of significant economic *** artificial cultivation of *** has thrived in recent decades,the advancement of selective breeding has been hindered by the lack of comprehensive population genomic *** this study,we identified over 8.73 million single nucleotide polymorphisms(SNPs)through whole-genome resequencing of 326 individuals spanning six distinct ***,we categorized 226 individuals with high-coverage sequencing depth(≥14×)into eight clusters based on their genetic profiles and phylogenetic ***,four of these clusters exhibited pronounced genetic differentiation compared with the other *** identify potentially advantageous loci for ***,we examined genomic regions exhibiting selective sweeps by analyzing the nucleotide diversity(θπ)and fixation index(FST)in these four *** these high-coverage resequencing data,we successfully constructed the first haplotype reference panel specific to *** achievement holds promise for enabling high-quality,***,we combined low-coverage sequencing data with imputation techniques for a genome-wide association study,aiming to identify candidate SNP loci and genes associated with growth traits.A significant concentration of these genes was observed on chromosome 17,which is primarily involved in skeletal muscle and embryonic development and cell ***,our detailed investigation of growth-related SNPs across the eight clusters revealed that cluster 5 harbored the most promising candidate SNPs,showing potential for genetic selective breeding *** findings provide a robust toolkit and valuable insights into the management of germplasm resources and genome-driven breeding initiatives targeting ***.

关键词： Plectropomus leopardus Whole-genome resequencing Growth Haplotype reference panel Single nucleotide polymorphisms

半无限介质多自由度频响函数离散时间有理近似的稳定参数识别

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工程力学 2024年第8期41卷 1-10页

作者：李鑫唐贞云杜修力北京工业大学城市与工程安全减灾教育部重点试验室北京100124

离散时间有理近似函数是将半无限土频响函数转化为时域模型的重要工具,离散时间有理近似函数和时域模型具有相同的稳定性和精度。目前关于离散时间有理近似函数的研究只针对于单自由度系统。该文基于线性控制理论,给出了多自由度有理近... 详细信息

离散时间有理近似函数是将半无限土频响函数转化为时域模型的重要工具,离散时间有理近似函数和时域模型具有相同的稳定性和精度。目前关于离散时间有理近似函数的研究只针对于单自由度系统。该文基于线性控制理论,给出了多自由度有理近似系统的稳定条件。将稳定性条件与遗传-序列二次算法相结合,开发了多自由度频响函数参数辨识方法,保证了多自由度系统的稳定性和精度。不同维度的多自由度有理近似系统的数值仿真验证了该文方法可以保证多自由度有理近似系统的稳定性和精度。

关键词：离散时间有理近似函数多自由度参数识别稳定性精度

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Hydrogen sulfide reduces oxidative stress in Huntington's disease via Nrf2

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Neural Regeneration Research 2025年第6期20卷 1776-1788页

作者： Zige Jiang Dexiang Liu Tingting Li Chengcheng Gai Danqing xin Yijing Zhao Yan Song Yahong Cheng Tong Li zhen.Wang Department of Physiology School of Basic Medical SciencesCheeloo College of MedicineShandong UniversityJinanShandong ProvinceChina Department of Medical Psychology and Ethics School of Basic Medicine SciencesCheeloo College of MedicineShandong UniversityJinanShandong ProvinceChina Department of Neurosurgery Surgery Qingdao Municipal HospitalQingdaoShandong ProvinceChina

The pathophysiology of Huntington's disease involves high levels of the neurotoxin quinolinic acid. Quinolinic acid accumulation results in oxidative stress, which leads to neurotoxicity. However, the molecular and cellular mechanisms by which quinolinic acid contributes to Huntington's disease pathology remain unknown. In this study, we established in vitro and in vivo models of Huntington's disease by administering quinolinic acid to the PC12 neuronal cell line and the striatum of mice, respectively. We observed a decrease in the levels of hydrogen sulfide in both PC12 cells and mouse serum, which was accompanied by down-regulation of cystathionine β-synthase, an enzyme responsible for hydrogen sulfide production. However, treatment with NaHS(a hydrogen sulfide donor) increased hydrogen sulfide levels in the neurons and in mouse serum, as well as cystathionine β-synthase expression in the neurons and the mouse striatum, while also improving oxidative imbalance and mitochondrial dysfunction in PC12 cells and the mouse striatum. These beneficial effects correlated with upregulation of nuclear factor erythroid 2-related factor 2 expression. Finally, treatment with the nuclear factor erythroid 2-related factor 2inhibitor ML385 reversed the beneficial impact of exogenous hydrogen sulfide on quinolinic acid-induced oxidative stress. Taken together, our findings show that hydrogen sulfide reduces oxidative stress in Huntington's disease by activating nuclear factor erythroid 2-related factor 2,suggesting that hydrogen sulfide is a novel neuroprotective drug candidate for treating patients with Huntington's disease.

关键词： apoptosis cystathionine-β-synthase nuclear factor erythroid 2-related factor 2 Huntington's disease hydrogen sulfide mitochondrion neuroplasticity oxidative stress quinolinic acid reactive oxygen species

Unveiling the early stage evolution of local atomic structures in the crystallization process of a metallic glass

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Chinese Physics B 2024年第3期33卷 58-64页

作者：马琳杨晓东杨锋周鑫嘉武振伟 Institute of Nonequilibrium Systems School of Systems ScienceBeijing Normal UniversityBeijing 100875China

The early stage evolution of local atomic structures in a multicomponent metallic glass during its crystallization process has been investigated via molecular dynamics *** is found that the initial thermal stability and earliest stage evolution of the local atomic clusters show no strong correlation with their initial short-range orders,and this leads to an observation of a novel symmetry convergence phenomenon,which can be understood as an atomic structure manifestation of the ***,in our system we have quantitatively proved that the crucial factor for the thermal stability against crystallization exhibited by the metallic glass is not the total amount of icosahedral clusters,but the degree of global connectivity among them.

关键词： metallic glass crystallization molecular dynamics simulation local atomic clusters

Contamination assessment,source apportionment and associated health risks of PTEs in agricultural soil under five land-use patterns in Sanya,China

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China Geology 2024年第3期7卷 469-479页

作者： Jian-zhou Yang Yan-gang Fu Qiu-li Gong Sheng-ming Ma Jing-jing Gong Jian-weng Gao zhen.liang Wang Yong-wen Cai Shi-xin Tang Institute of Geophysical and Geochemical Exploration Chinese Academy of Geological SciencesChina Geological SurveyLangfang 065000China Key Laboratory of Coupling Process and Effect of Natural Resources Elements Ministry of Natural ResourcesBeijing 100055China

To understand the levels of potentially toxic elements(PTEs)contamination in soils and their effects on human health from different agricultural land use in Sanya,China.128 soil samples(64 topsoil samples and corresponding subsoil samples)were collected from the five representative land-use *** coupled plasma mass spectrometry(ICP-MS),Atomic fluorescence spectrometry(AFS),and Inductively coupled plasma optical emission spectrometry(ICP-OES)were used to determine the content of PTEs(As,Cd,Hg,Cu,Cr,Ni,Pb,Zn,Co,Mo,Sb,and V).Correlation analysis and factor analysis were used to determine the source of ***-accumulation index(I_(geo)),hazard quotient(HQ),and total carcinogenic risk index(TR)were used to measure the PTEs contamination and its relative health *** showed that the average values of 12 PTEs in topsoil were higher than the Hainan soil geochemical baseline,showing different degrees of PTEs accumulation *** concentration of PTEs in the topsoil was lower than those in the subsoil except for Cd and *** I_(geo)revealed that the major accumulated element in soils was As followed by *** apportionment suggested that parent materials and agricultural practices were the dominant factors for PTEs accumulation in the *** risks of soil samples from five land-use patterns presented a trend of paddy field>dry field>woodland>orchard>garden ***,the HQ values of 12 PTEs were less than the recommended limit of HQ=1,representing that there are no non-carcinogenic risks of PTEs for children and adults in the study *** TR values are within 6.95×10^(-6)-1.38×10^(-5),which corresponds to the low *** the PTEs in the agricultural soil of the study area show little influence on the health status of the local population.

关键词： Potentially toxic trace elements(PTEs) Soils Land-use Geo-accumulation index(Igeo) Hazard quotient(HQ) Total carcinogenic risk index(TR) Source apportionment Health risk Agricutural geological survey engineering

Prediction model for hepatitis B e antigen seroconversion in chronic hepatitis B with peginterferon-alfa treated based on a responseguided therapy strategy

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World Journal of Hepatology 2024年第3期16卷 405-417页

作者： Pei-xin Zhang Xiao-Wei zhen. Ya-Fei Zhang Jun Ye Wei Li Qian-Qian Tang Jie Zhu Gui-Zhou Zou zhen.Hua Zhang Department of Infectious Diseases The Second Affiliated Hospital of Anhui Medical UniversityHefei 230601Anhui ProvinceChina Department of Infectious Diseases Anhui Provincial HospitalHefei 230000Anhui ProvinceChina Department of Hepatology The Second People’s Hospital of Fuyang CityFuyang 236000Anhui ProvinceChina

BACKGROUND Models for predicting hepatitis B e antigen(HBeAg)seroconversion in patients with HBeAg-positive chronic hepatitis B(CHB)after nucleos(t)ide analog treatment are *** To establish a simple scoring model based on a response-guided therapy(RGT)strategy for predicting HBeAg seroconversion and hepatitis B surface antigen(HBsAg)*** In this study,75 previously treated patients with HBeAg-positive CHB underwent a 52-week peginterferon-alfa(PEG-IFNα)treatment and a 24-wk *** regression analysis was used to assess parameters at baseline,week 12,and week 24 to predict HBeAg seroconversion at 24 wk *** two best predictors at each time point were used to establish a prediction model for PEG-IFNαtherapy *** at each time point that met the corresponding optimal cutoff thresholds were scored as 1 or *** The two most meaningful predictors were HBsAg≤1000 IU/mL and HBeAg≤3 S/CO at baseline,HBsAg≤600 IU/mL and HBeAg≤3 S/CO at week 12,and HBsAg≤300 IU/mL and HBeAg≤2 S/CO at week *** a total score of 0 vs 2 at baseline,week 12,and week 24,the response rates were 23.8%,15.2%,and 11.1%vs 81.8%,80.0%,and 82.4%,respectively,and the HBsAg clearance rates were 2.4%,3.0%,and 0.0%,vs 54.5%,40.0%,and 41.2%,*** We successfully established a predictive model and diagnosis-treatment process using the RGT strategy to predict HBeAg and HBsAg seroconversion in patients with HBeAg-positive CHB undergoing PEG-IFNαtherapy.

关键词： Chronic hepatitis B Hepatitis B e antigen-positive Peginterferon-alfa Prediction model Response-guided therapy strategy

Does China's digital economy contribute to low-carbon transition?

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Ecological Economy 2024年第2期20卷 102-122页

作者： LI Jun-jun HUANG xin-yu CHEN Mu ZHANG Meng-jiang ZHANG zhen School of Economics Fujian Normal UniversityFuzhou 350007CHINA College of Mechanical and Electrical Engineering Wuyi UniversityNanping 354300CHINA

The digital economy,as a new emerging economic form,has become an important power for realizing Chinese-style modernization and promoting green development in *** paper measures the digital economy and low-carbon transition index based on the data of 30 provinces in China from 2013 to 2020 and analyzes the mechanism and path of the digital economy affecting low-carbon transition using the fixed effect panel data model and the threshold effect *** is found that,(1)The digital economy and low-carbon transition in China are various in different regions,with characteristics of being unbalanced and insufficient.(2)The digital economy significantly promotes low-carbon transition,with the greatest influence in the Central region,followed by the Eastern region and the Western *** different dimensions,the development of informatization and digital transactions promote low-carbon transition,but the development of the internet plays an inhibiting role.(3)The higher the degree of urbanization and environmental regulation,the greater the influence of the digital economy on low-carbon transition.

关键词： digital economy low-carbon transition threshold effect model instrumental variables quantile regression

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地震后建筑结构层间变形特征分布

吉林大学学报（工学版） 2024年第5期54卷 1377-1384页

作者：邸振勇杨新辉西南大学审计处重庆400715 中国建筑科学研究院地基基础研究所北京100013

进行建筑结构层间变形特征分析时未建模分析特征,导致分析效果较差,为解决上述问题,本文对地震后建筑结构层间变形分布特征展开研究。利用建筑信息模型技术建立建筑结构三维模型;引入广义层间位移谱法,构建层间位移等公式,进行建筑结构... 详细信息

进行建筑结构层间变形特征分析时未建模分析特征,导致分析效果较差,为解决上述问题,本文对地震后建筑结构层间变形分布特征展开研究。利用建筑信息模型技术建立建筑结构三维模型;引入广义层间位移谱法,构建层间位移等公式,进行建筑结构层间变形特征分布分析。研究结果表明:不同加速度下,层间位移随着加速度增加而增大;1层楼时弯矩、剪力和层间位移角分别达到237 kN·m、210 kN和1/231 rad,呈现最大的变化。分析结果与实际相符,可以有效地分析层间变形特征。

关键词：建筑信息模型技术建筑结构层间变形分布特征三维模型层间位移谱