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Direct Synthesis of α-Aminophosphonates from Amines,Alcohols,and White Phosphorus

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CCS Chemistry 2024年第1期6卷 91-99页

作者： Mengpei Bai yinwei Cao Junwei Huang yan Liu Guo tang yufen Zhao Department of Chemistry and Key Laboratory for Chemical Biology of Fujian Province College of Chemistry and Chemical EngineeringXiamen UniversityXiamenFujian 361005

Developing practical strategies for the synthesis of organophosphorus compounds(OPCs)from white phosphorus(P_(4))without the use of Cl_(2) and PCl_(3) remains a significant *** first multicomponent oxidative α-phosphonylation of amines with P_(4) and alcohols has been *** the use of copper(Ⅱ)as the catalyst and air as the safe oxidant,structurally sophisticated α-aminophosphonates have been prepared in high ***,this method is also suitable for selective construction of P-O-P *** reaction is characterized by a complete conversion of P_(4).The activation of P_(4) with transition metals often leads to formation of complexes[M_(x)P_(y)]_(n) associated with the deactivation of transition *** breakthrough showcases the potential of transition-metal-catalyzed reactions in elemental phosphorus chemistry.

关键词： white phosphorus P-C bonds dialkyl phosphites aminophosphonates pyrophosphates

Highly efficient tunable photodetector with a bipolar response in van der Waals heterojunctions

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Science China(Technological Sciences) 2024年第2期67卷 639-646页

作者： SHI ChaoFan ZHANG Shi XIAO KeNing ZHANG LiBo HAN Li ZHU yuLin tang WeiWei LIU ChangLong LI GuanHai CHEN XiaoShuang College of Physics and Optoelectronic Engineering Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences Hangzhou310024China State Key Laboratory of Infrared Physics Shanghai Institute of Technical PhysicsChinese Academy of SciencesShanghai 200083China

The heterojunction integration of two-dimensional(2D)materials via van der Waals(vdW)forces,unencumbered by lattice and processing constraints,constitutes an efficacious approach to enhance the overall optoelectronic performance of photodetectors,due to an assortment of distinctive light-matter ***,vdW heterojunction photodetectors based on transition metal dichalcogenides(TMDs)face an inevitable trade-off between low dark currents and high responsivity,curtailing the application potential of myriad novel optoelectronic components in sensing,spectral,and communication *** this study,we present the successful actualization of a highly sensitive,self-powered,and gate-tunable bipolar response *** mechanisms underlying photocurrent generation were scrutinized via bias-,power-,and position-dependent mapping photoresponse measurements,identifying the photovoltaic effect,which is attributable to the Schottky junction’s built-in electric field,as the predominant *** prototype Au-WS2-graphene photodetector exhibits a remarkable light on/off ratio of 1.2×10^(6),a specific detectivity of 6.12×10^(11)cm H^(z1/2)W^(-1)with 20μs response time at 638 *** wide gate-tunable responsivity provides an adjustability scope,ranging from 0.9 to 3.1 A W^(-1).Notably,the device demonstrates an exceptional linear photocurrent response,with a linear dynamic range(LDR)value approximating 130 dB,which significantly surpasses that of other photodetectors based on TMDs.

关键词： WS2/graphene van der Waals heterojunction gate-tunable bipolar response

Prediction of soil organic carbon stock combining Sentinel-1 and Sentinel-2 images in the Zoige Plateau, the northeastern Qinghai-Tibet Plateau

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Ecological Processes 2024年第2期13卷 165-176页

作者： Junjie Lei Changli Zeng Lv Zhang Xiaogang Wang Chanhua Ma Tao Zhou Benjamin Laffitte Ke Luo Zhihan yang Xiaolu tang State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Sichuan Academy of Geological Survey Sichuan Institute of Nuclear Geological Survey College of Earth Sciences Chengdu University of Technology Tianfu yongxing Laboratory

Background Soil organic carbon（SOC） is a critical component of the global carbon cycle, and an accurate estimate of regional SOC stock（SOCS） would significantly improve our understanding of SOC sequestration and cycles. Zoige Plateau, locating in the northeastern Qinghai-Tibet Plateau, has the largest alpine marsh wetland worldwide and exhibits a high sensitivity to climate fluctuations. Despite an increasing use of optical remote sensing in predicting regional SOCS, optical remote sensing has obvious limitations in the Zoige Plateau due to highly cloudy weather, and knowledge of on the spatial patterns of SOCS is limited. Therefore, in the current study, the spatial distributions of SOCS within 100 cm were predicted using an XGBoost model—a machine learning approach, by integrating Sentinel-1, Sentinel-2 and field observations in the Zoige *** The results showed that SOC content exhibited vertical distribution patterns within 100 cm, with the highest SOC content in topsoil. The tenfold cross-validation approach showed that XGBoost model satisfactorily predicted the spatial patterns of SOCS with a model efficiency of 0.59 and a root mean standard error of 95.2 Mg ha-1. Predicted SOCS showed a distinct spatial heterogeneity in the Zoige Plateau, with an average of 355.7 ± 123.1 Mg ha-1within 100 cm and totaled 0.27 × 10～9 Mg *** High SOC content in topsoil highlights the high risks of significant carbon loss from topsoil due to human activities in the Zoige Plateau. Combining Sentinel-1 and Sentinel-2 satisfactorily predicted SOCS using the XGBoost model, which demonstrates the importance of selecting modeling approaches and satellite images to improve efficiency in predicting SOCS distribution at a fine spatial resolution of 10 m. Furthermore, the study emphasizes the potential of radar（Sentinel-1） in developing SOCS mapping, with the newly developed fine-resolution mapping having important applications in land management, ecological resto

关键词： SOC Vegetation index Texture XGBoost Sentinel-1 Sentinel-2

基于数据迁移下Bayes特征融合可靠度评估模型

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航空动力学报 2024年第3期39卷 173-181页

作者：张晓洁唐家银唐莉西南交通大学数学学院成都611756 西南交通大学综合交通大数据应用技术国家工程实验室成都611756

基于同种产品的多类试验源寿命数据信息,利用不同数据源间的映射关系,将多源数据迁移至现场数据源中形成混合数据源,以此作为产品可靠性贝叶斯统计分析基础。对于不同应力下加速寿命数据,将其折算至常应力水平下确定参数分布密度函数解... 详细信息

基于同种产品的多类试验源寿命数据信息,利用不同数据源间的映射关系,将多源数据迁移至现场数据源中形成混合数据源,以此作为产品可靠性贝叶斯统计分析基础。对于不同应力下加速寿命数据,将其折算至常应力水平下确定参数分布密度函数解析,以此作为产品可靠性贝叶斯统计分析的先验条件。将贝叶斯统计模型与数据迁移模型进行结合,融合多源数据的同时确定其参数估计值,得到产品密度函数解析并完成产品可靠性分析。算例表明:该类模型利用数据源间映射关系可有效实现数据迁移,且能实现加速寿命数据与其他各类数据源的同步融合,融合样本数据后的产品可靠性综合评估比单一寿命数据源的产品可靠性评估更全面、客观。

关键词：数据迁移贝叶斯数据融合指数分布可靠度

Analysis of Predictability of a Large-scale Short-duration Heavy Precipitation Process in Nanchang City

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Meteorological and Environmental Research 2024年第3期15卷 60-64页

作者： Chuanshi tang Nanchang Meteorological Bureau Nanchang 330038China

Based on the observation data of automatic stations and sounding data,the circulation characteristics and physical quantities of a large-scale short-duration heavy precipitation process in Nanchang City on July 7,2020 were diagnosed and analyzed,and the ability of several numerical forecasting products to predict this process was *** results show that the short-duration heavy precipitation process was triggered in the process of the subtropical high changing from lifting to the north to retreating to the south under the weather background of the confrontation between the northerly flow behind the trough and the strong southwest warm and wet flow on the north side of the subtropical *** strong southwest warm and wet flow provided abundant water vapor,and the southern pressing of the lower energy front and the invasion of the cold air near the surface layer provided unstable energy and dynamic conditions for the heavy *** changing trend of the subtropical high from lifting to the north to retreating to the south during 08:00 to 20:00 on July 7 was not predicted by numerical forecast,and there was a large deviation in the forecast of the time and intensity of the southern pressing of the northerly flow behind the trough,so the guidance of numerical forecast for heavy precipitation was not strong,which was not conducive to the prediction of the short-duration heavy *** was predicted that the subtropical high would move slightly to the south on July 6 compared with the previous day,and the forecast adjustment of the high-level weather system can be used as a sign of the forecast change,which needs to be paid certain attention in the daily forecast.

关键词： Short-term heavy precipitation Predictability Test Evaluation

Identification of 3-ketocapnine reductase activity within the human microbiota

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mLife 2024年第2期3卷 307-316页

作者： Xiaotong Wu Lukuan Hou Haili Zhang yi Ma Jufang Wang Mingwei Cai Xiaoyu tang School of Biology and Biological Engineering South China University of TechnologyGuangzhouChina Institute of Chemical Biology Shenzhen Bay LaboratoryShenzhenChina College of Chemistry and Pharmacy Northwest A&F UniversityYanglingChina

The microbial synthesis of sulfonolipids within the human body is likely involved in maintaining human health or causing ***,the enzymes responsible for their biosynthesis remain largely *** this study,we identified and verified the role of 3-ketocapnine reductase,the third-step enzyme,in the four-step conversion of L-phosphoserine into sulfobacin B both in vivo and in *** finding builds upon our previous research into sulfonolipid biosynthesis,which focused on the vaginal bacterium Chryseobacterium gleum DSM 16776 and the gut bacterium Alistipes finegoldii DSM *** comprehensive gene mapping,we demonstrate the widespread presence of potential sulfonolipid biosynthetic genes across diverse bacterial species inhabiting various regions of the human *** findings shed light on the prevalence of sulfonolipid-like metabolites within the human microbiota,suggesting a potential role for these lipid molecules in influencing the intricate biointeractions within the complex microbial ecosystem of the human body.

关键词： 3-ketocapnine reductase capnines human microbiota sulfonolipids

Cav3.2 channel regulates cerebral ischemia/reperfusion injury:a promising target for intervention

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Neural Regeneration Research 2024年第11期19卷 2480-2487页

作者： Feibiao Dai Chengyun Hu Xue Li Zhetao Zhang Hongtao Wang Wanjun Zhou Jiawu Wang Qingtian Geng yongfei Dong Chaoliang tang Graduate School Wannan Medical CollegeWuhuAnhui ProvinceChina Department of Anesthesiology The First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui ProvinceChina Core Facility Center for Medical Sciences The First Affiliated Hospital of USTC(Anhui Provincial Hospital)HefeiAnhui ProvinceChina Department of Pharmacy The First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui ProvinceChina Department of Neurosurgery The First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui ProvinceChina

Calcium influx into neurons triggers neuronal death during cerebral ischemia/reperfusion *** calcium channels are involved in cerebral ischemia/reperfusion ***3.2 channel is a main subtype of T-type calcium channels.T-type calcium channel blockers,such as pimozide and mibefradil,have been shown to prevent cerebral ischemia/reperfusion injury-induced brain ***,the role of Cav3.2 channels in cerebral ischemia/reperfusion injury remains ***,in vitro and in vivo models of cerebral ischemia/reperfusion injury were established using middle cerebral artery occlusion in mice and high glucose hypoxia/reoxygenation exposure in primary hippocampal *** results showed that Cav3.2 expression was significantly upregulated in injured hippocampal tissue and primary hippocampal *** further established a Cav3.2 gene-knockout mouse model of cerebral ischemia/reperfusion ***3.2 knockout markedly reduced infarct volume and brain water content,and alleviated neurological dysfunction after cerebral ischemia/reperfusion ***,Cav3.2 knockout attenuated cerebral ischemia/reperfusion injury-induced oxidative stress,inflammatory response,and neuronal *** the hippocampus of Cav3.2-knockout mice,calcineurin overexpression offset the beneficial effect of Cav3.2 knockout after cerebral ischemia/reperfusion *** findings suggest that the neuroprotective function of Cav3.2 knockout is mediated by calcineurin/nuclear factor of activated T cells 3 *** from this study suggest that Cav3.2 could be a promising target for treatment of cerebral ischemia/reperfusion injury.

关键词： calcineurin Cav3.2 channel cerebral ischemia/reperfusion hippocampus hypoxia/reoxygenation inflammatory response nuclear factor of activated T cells 3 oxidative stress primary hippocampal neurons stroke

On the Identification of N-rich Metal-poor Field Stars with Future Chinese Space Station Telescope

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Research in Astronomy and Astrophysics 2024年第1期24卷 151-164页

作者： Jiajun Zhang Baitian tang Jiang Chang Xiangxiang Xue JoséGFernández-Trincado Chengyuan Li Long Wang Hao Tian yang Huang School of Physics and Astronomy Sun Yat-sen UniversityZhuhai 519082China CSST Science Center for the Guangdong-Hong Kong-Macao Greater Bay Area Sun Yat-sen UniversityZhuhai 519082China Purple Mountain Observatory Chinese Academy of SciencesNanjing 210034China Key Lab of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Instituto de Astronomía Universidad Católica del NorteAv.Angamos 0610AntofagastaChile Key Lab of Space Astronomy and Technology National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China

During the long term evolution of globular clusters(GCs), some member stars are lost to the field. The recently found nitrogen-rich(N-rich) metal-poor field stars are promising candidates of these GC escapees, since N enhancement is the fingerprint of chemically enhanced populations in GCs. In this work, we discuss the possibility of identifying N-rich metal-poor field stars with the upcoming Chinese Space Station Telescope(CSST). We focus on the main survey camera with NUV, u, g, r, i, z, y filters and slitless spectrograph with a resolution about *** combination of UV sensitive equipment and prominent N-related molecular lines in the UV band bodes well for the identification: the color–color diagram of(u-g) versus(g-r) is capable of separating N-rich field stars from normal halo stars, if metallicity can be estimated without using the information on u-band ***, the synthetic spectra show that a signal-to-noise ratio of 10 is sufficient to identify N-rich field stars. In the near future, a large sample of N-rich field stars found by CSST, combined with state-of-the-art N-body simulations will be crucial to deciphering GC-Galaxy co-evolution.

关键词： stars:chemically peculiar stars:abundances techniques:photometric techniques:spectroscopic

Improved genome annotation of Brassica oleracea highlights the importance of alternative splicing

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Horticultural Plant Journal 2024年第4期10卷 961-970页

作者： yinqing yang Lei Zhang Qi tang Lingkui Zhang Xing Li Shumin Chen Kang Zhang ying Li Xilin Hou Feng Cheng State Key Laboratory of Crop Genetics and Germplasm Enhancement College of HorticultureNanjing Agricultural UniversityNanjing 210095China State Key Laboratory of Vegetable Biobreeding Institute of Vegetables and FlowersChinese Academy of Agricultural SciencesKey Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry of Agriculture and Rural AffairsSino-Dutch Joint Laboratory of Horticultural GenomicsBeijing 100081China

Brassica oleracea has been developed into many important crops,including cabbage,kale,cauliflower,broccoli and so *** genome and gene annotation of cabbage(cultivar JZS),a representative morphotype of ***,has been widely used as a common reference in biological *** its genome assembly has been updated twice,the current gene annotation still lacks information on untranslated regions(UTRs)and alternative splicing(AS).Here,we constructed a high-quality gene annotation(JZSv3)using a full-length transcriptome acquired by nanopore sequencing,yielding a total of 59452 genes and 75684 ***,we re-analyzed the previously reported transcriptome data related to the development of different tissues and cold response using JZSv3 as a reference,and found that 3843 out of 11908 differentially expressed genes(DEGs)underwent AS during the development of different tissues and 309 out of 903 cold-related genes underwent AS in response to cold ***,we also identified many AS genes,including BolLHCB5 and BolHSP70,that displayed distinct expression patterns within variant transcripts of the same gene,highlighting the importance of JZSv3 as a pivotal reference for AS ***,JZSv3 provides a valuable resource for exploring gene function,especially for obtaining a deeper understanding of AS regulation mechanisms.

关键词： Brassica oleracea Oxford nanopore technologies Gene annotation Alternative splicing