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Filling the gaps in icosahedral superatomic metal clusters

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National Science Review 2024年第7期11卷 168-176页

作者： Wei-Miao He Jia-Hua Hu Yu-Jia Cui Jing Li Yu-Bing Si Shuai-Bo wang Yu-Jing Zhao Zhan Zhou Lu-Fang Ma Shuang-Quan Zang College of Chemistry Zhengzhou University School of Science Xuchang University College of Chemistry and Chemical Engineering Henan Key Laboratory of Function-Oriented Porous MaterialsLuoyang Normal University

Chemically modified superatoms have emerged as promising candidates in the new periodic table, in which Au13and its doped M_nAu13-nhave been widely studied. however, their important counterpart, Ag13artificial element, has not yet been synthesized. In this work, we report the synthesis of Ag13nanoclusters using strong chelating ability and rigid ligands, that fills the gaps in the icosahedral superatomic metal clusters. After further doping Ag13template with different degrees of Au atoms, we gained insight into the evolution of their optical properties. Theoretical calculations show that the kernel metal doping can modulate the transition of the excited-state electronic structure, and the electron transfer process changes from local excitation（LE） to charge transfer（CT） to LE. This study not only enriches the families of artificial superatoms, but also contributes to the understanding of the electronic states of superatomic clusters.

关键词： icosahedral superatomic metal clusters analog clusters photoluminescence alloying near-infrared quantum yield

滋水清肝饮加味方治疗肝郁肾虚型抑郁症的临床研究

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中医药导报 2024年第8期30卷 87-91页

作者：胡域锋王革生裴清华郑粲北京中医药大学第三临床医学院北京100029 北京中医药大学东方医院北京100078

目的:评价滋水清肝饮加味方治疗肝郁肾虚型抑郁症的临床疗效。方法:将72例肝郁肾虚型轻中度抑郁症患者随机分为试验组与对照组,每组36例。试验组患者口服滋水清肝饮加味方联合氟西汀,对照组患者单独口服氟西汀。疗程6周。采用汉密尔顿... 详细信息

目的:评价滋水清肝饮加味方治疗肝郁肾虚型抑郁症的临床疗效。方法:将72例肝郁肾虚型轻中度抑郁症患者随机分为试验组与对照组,每组36例。试验组患者口服滋水清肝饮加味方联合氟西汀,对照组患者单独口服氟西汀。疗程6周。采用汉密尔顿抑郁量表评分和中医证候评分对患者表现评价。结果:试验组抗抑郁效果优于对照组(P<0.05)。HAMD总分与中医证候总分在时间点比较及交互作用均有明显差异(P<0.05)。两组患者在治疗2、4、6周时HAMD总分和中医症状评分均低于治疗前(P<0.05)。HAMD评分结果显示,与对照组相比,试验组抑郁情绪、入睡困难、躯体性焦虑、强迫症状等改善明显,而工作和兴趣、能力减退、绝望感则无明显改善。结论:滋水清肝饮加味方加氟西汀治疗肝郁肾虚型轻中度抑郁症优于氟西汀单药治疗。该治疗方法在减轻焦虑和抑郁症状、躯体化不适和改善睡眠质量等方面疗效优异。

关键词：抑郁症肝郁肾虚滋水清肝饮加味方氟西汀

客户数字化转型与企业营运资金管理效率——基于竞争侵占与约束防御的双重视角

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南方经济 2024年第8期 115-136页

作者：王娇王凡林首都经济贸易大学会计学院北京100070 首都经济贸易大学

无论在企业管理实践中,还是从已有文献来看,客户数字化转型对企业营运资金管理效率表现出促进还是抑制,仍未形成一致结论。文章采用中国深沪A股上市企业披露的前五大客户数据,探讨客户数字化转型对企业营运资金管理效率的溢出效应与作... 详细信息

无论在企业管理实践中,还是从已有文献来看,客户数字化转型对企业营运资金管理效率表现出促进还是抑制,仍未形成一致结论。文章采用中国深沪A股上市企业披露的前五大客户数据,探讨客户数字化转型对企业营运资金管理效率的溢出效应与作用机理。基准检验发现,客户数字化转型降低了企业营运资金管理效率,说明数字溢出存在负外部性。作用渠道检验发现,竞争侵占与约束防御是客户数字化转型影响企业营运资金管理效率的两大渠道,即客户数字化转型催生的数字溢出通过降低企业相对议价能力、降低企业应收账款回收率、加剧企业专用资产套牢风险、加大企业商业信用供给以及扩大企业存货储备规模进而降低了企业营运资金管理效率,说明数字溢出具有竞争约束特征。异质性检验发现,当客户集中度较低、企业规模较大、企业风险承担能力较强时,数字溢出的竞争约束特征得到缓解。研究结论解释了客户数字化转型是否能够提升企业营运资金管理效率的争议,发现了客户数字化转型引致的数字溢出具有竞争约束特征,并提供了企业克服数字溢出负外部性的理论指导,具有理论价值和现实意义。

关键词：数字化转型数字溢出供应链管理现金转换周期文本分析法

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Remote sensing and its applications using gNSS reflected signals:advances and prospects

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Satellite Navigation 2024年第1期5卷 10-51页

作者： Shuanggen Jin Adriano Camps Yan Jia Feng wang Manuel Martin-Neira Feixiong Huang Qingyun Yan Shuangcheng Zhang Zho.gyu Li Komi Edokossi Dongkai Yang Zhiyu Xiao Zho.gmin Ma Weihua Bai Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai200030China School of Surveying and Land Information Engineering Henan Polytechnic UniversityJiaozuo454003China Department of Signal Theory and Communications Technical University of CataloniaBarcelona08034Spain Department of Surveying and geoinformatics Nanjing University of Posts and TelecommunicationsNanjing210023China School of Electronics and Information Engineering Beihang UniversityBeijing100191China European Space Research and Technology Centre(ESTEC) European Space Agency2200-AGNoordwijkThe Netherlands National Space Science Center Chinese Academy of SciencesBeijing100190China School of Remote Sensing and geomatics Engineering Nanjing University of Information Science and TechnologyNanjing210044China College of geological Engineering and geomatics Chang’an UniversityXi’an710054China University of Electronic Science and Technology of China Chengdu611731China

The global Navigation Satellite Systems(gNSS),including the US’s gPS,China’s BDS,the European Union’s galileo,and Russia’s gLONASS,offer real-time,all-weather,any-time,anywhere and high precision observations by transmitting L band signals continuously,which have been widely used for positioning,navigation and *** the development of gNSS technology,it has been found that gNSS-reflected signals can be used to detect Earth’s surface characteristics together with other signals of *** this paper,the current status and latest advances are presented on global Navigation Satellite System-Reflectometry(gNSS-R)in theory,methods,techniques and *** developments and progresses in gNSS-R instruments,theoretical modeling,and signal processing,ground and space-/air-borne experiments,parameters retrieval(*** speed,sea surface height,soil moisture,ice thickness),sea surface altimetry and applications in the atmosphere,oceans,land,vegetation,and cryosphere are given and reviewed in ***,the challenges in the gNSS-R development of each field are also ***,the future applications and prospects of gNSS-R are discussed,including multi-gNSS reflectometry,new gNSS-R receivers,gNSS-R missions,and emerging applications,such as mesoscale ocean eddies,ocean phytoplankton blooms,microplastics detection,target recognition,river flow,desert studies,natural hazards and landslides monitoring.

关键词： gNSS Reflectometry Remote sensing Environmental change

Bioinspired anti-freezing 3D-printable conductive hydrogel microfibers for highly-sensitive and wide-range detection of ultralow and high strains

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green Chemical Engineering 2024年第1期5卷 132-143页

作者： Yi-Min Yang Ting-Yuan Hu Haidong Fan Lu Shi Shi-Yuan Zhang Zhuang Liu Xiao-Jie Ju Rui Xie Wei wang Liang-Yin Chu School of Chemical Engineering Sichuan UniversityChengdu610065China Department of Mechanics Sichuan UniversityChengdu610065China State Key Laboratory of Polymer Materials Engineering Sichuan UniversityChengdu610065China

Soft strain sensors that can transduce stretch stimuli into electrical readouts are promising as sustainable wearable ***,most strain sensors cannot achieve highly-sensitive and wide-range detection of ultralow and high *** by bamboo structures,anti-freezing microfibers made of conductive poly(vinyl alcohol)hydrogel with poly(3,4-ethylenedioxythiphene)-poly(styrenesulfonate)are developed via continuous microfluidic *** microfibers provide unique bamboo-like structures with enhanced local stress to improve both their length change and resistance change upon stretching for efficient signal *** microfibers allow highlysensitive(detection limit:0.05%strain)and wide-range(0%-400%strain)detection of ultralow and high strains,as well as features of good stretchability(485%strain)and anti-freezing property(freezing temperature:-41.1°C),fast response(200 ms),and good *** experimental results,together with theoretical foundation analysis and finite element analysis,prove their enhanced length and resistance changes upon stretching for efficient signal *** integrating microfluidic spinning with 3D-printing technique,the textiles of the microfibers can be flexibly *** microfibers and their 3D-printed textiles enable highperformance monitoring of human motions including finger bending and throat vibrating during *** work provides an efficient and general strategy for developing advanced conductive hydrogel microfibers as highperformance wearable strain sensors.

关键词： Conductive hydrogel microfibers Microfluidics Sensitive detection Wide detection range Anti-freezing

Versatile plant genome engineering using anti-CRISPR-Cas12a systems

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Science China Life Sciences 2024年

作者： Yao He Shishi Liu Long Chen Dongkai Pu Zhaohui Zho.g Tang Xu Qiurong Ren Chuan Dong Yawei wang Danning wang Xuelian Zheng Fengbiao guo Tao Zhang Yiping Qi Yong Zhang Integrative Science Center of germplasm Creation in Western China (Cho.gqing) Science City Chongqing Key Laboratory of Tree Germplasm Innovation and Utilization School of Life Sciences Southwest University Department of Biotechnology School of Life Sciences and Technology Center for Informational Biology University of Electronic Science and Technology of China Sichuan Institute of Edible Fungi Sichuan Academy of Agricultural Sciences Jiangsu Key Laboratory of Crop genomics and Molecular Breeding/Zho.gshan Biological Breeding Laboratory/Key Laboratory of Plant Functional genomics of the Ministry of Education College of AgricultureYangzhou University Jiangsu Co-Innovation Center for Modern Production Technology of grain Crops/Jiangsu Key Laboratory of Crop genetics and Physiology Yangzhou University Department of Respiratory and Critical Care Medicine Zhongnan Hospital of Wuhan University Key Laboratory of Combinatorial Biosynthesis and Drug Discovery Ministry of Education and School of Pharmaceutical Sciences Wuhan University Department of Plant Science and Landscape Architecture University of Maryland College Park 20742 Institute for Bioscience and Biotechnology Research University of Maryland

CRISPR-Cas12a genome engineering systems have been widely used in plant research and crop breeding. To date, the performance and use of anti-CRISPR-Cas12a systems have not been fully established in plants. Here, we conduct in silico analysis to identify putative anti-CRISPR systems for Cas12a. These putative anti-CRISPR proteins, along with known anti-CRISPR proteins, are assessed for their ability to inhibit Cas12a cleavage activity in vivo and in planta. Among all anti-CRISPR proteins tested, AcrVA1 shows robust inhibition of Mb2Cas12a and LbCas12a in E. coli. Further tests show that AcrVA1 inhibits LbCas12a mediated genome editing in rice protoplasts and stable transgenic lines. Impressively, co-expression of AcrVA1 mitigates off-target effects by CRISPR-LbCas12a, as revealed by whole genome sequencing. In addition, transgenic plants expressing AcrVA1 exhibit different levels of inhibition to LbCas12a mediated genome editing, representing a novel way of fine-tuning genome editing efficiency. By controlling temporal and spatial expression of AcrVA1, we show that inducible and tissue specific genome editing can be achieved in plants. Furthermore, we demonstrate that AcrVA1 also inhibits LbCas12a-based CRISPR activation(CRISPRa) and based on this principle we build logic gates to turn on and off target genes in plant cells. Together, we have established an efficient anti-CRISPR-Cas12a system in plants and demonstrate its versatile applications in mitigating off-target effects, finetuning genome editing efficiency, achieving spatial-temporal control of genome editing, and generating synthetic logic gates for controlling target gene expression in plant cells.

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10-Million Atoms Simulation of First-Principle Package LS3DF

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Journal of Computer Science & Technology 2024年第1期39卷 45-62页

作者：严昱瑾李海波赵曈汪林望石林刘涛谭光明贾伟乐孙凝晖 State Key Laboratory of Processors Institute of Computing TechnologyChinese Academy of SciencesBeijing 100190 China University of Chinese Academy of Sciences Beijing 101408China Computing System Optimization Laboratory Huawei TechnologiesBeijing 100094China Institute of Semiconductors Chinese Academy of SciencesBeijing 100083China School of Materials Science and Engineering Yancheng Institute of TechnologyYancheng 224051China

The growing demand for semiconductor devices simulation poses a big challenge for large-scale electronic structure *** various methods,the linearly scaling three-dimensional fragment(LS3DF)method exhibits excellent scalability in large-scale *** on algorithmic and system-level optimizations,we propose a highly scalable and highly efficient implementation of LS3DF on a domestic heterogeneous supercomputer equipped with *** terms of algorithmic optimizations,the original all-band conjugate gradient algorithm is refined to achieve faster convergence,and mixed precision computing is adopted to increase overall *** terms of system-level optimiza-tions,the original two-layer parallel structure is replaced by a coarse-grained parallel *** strategies such as multi-stream,kernel fusion,and redundant computation removal are proposed to increase further utilization of the com-putational power provided by the heterogeneous *** a result,our optimized LS3DF can scale to a 10-million sili-con atoms system,attaining a peak performance of 34.8 PFLOPS(21.2% of the peak).All the improvements can be adapt-ed to the next-generation supercomputers for larger simulations.

关键词： single instruction multiple thread accelerator electronic structure high-performance computing linearly scaling three-dimensional fragment(LS3DF)

Data-flow in mobile edge computing networks: end-to-end performance analysis using stochastic network calculus

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The Journal of China Universities of Posts and Telecommunications 2022年第1期29卷 81-92页

作者： Zhu Xiaorong Jing Chuanfang Shi Jindou wang Yong ho Chifong College of Telecommunications and Information Engineering Nanjing University of Posts and TelecommunicationNanjing 210003China School of Electrical Engineering Nanjing Vocational University of Industry TechnologyNanjing 210003China Ultra Intelligent Technology Company Limited MacaoChina

Mobile edge computing(MEC) networks can provide a variety of services for different applications. End-to-end performance analysis of these services serves as a benchmark for the efficient planning of network resource allocation and routing strategies. In this paper, a performance analysis framework is proposed for the end-to-end data-flows in MEC networks based on stochastic network calculus(SNC). Due to the random nature of routing in MEC networks, probability parameters are introduced in the proposed analysis model to characterize this randomness into the derived expressions. Taking actual communication scenarios into consideration, the end-to-end performance of three network data-flows is analyzed, namely, voice over Internet protocol(VoIP), video, and file transfer protocol(FTP). These network data-flows adopt the preemptive priority scheduling scheme. Based on the arrival processes of these three data-flows, the effect of interference on their performances and the service capacity of each node in the MEC networks, closed-form expressions are derived for showing the relationship between delay, backlog upper bounds, and violation probability of the data-flows. Analytical and simulation results show that delay and backlog performances of the data-flows are influenced by the number of hops in the network and the random probability parameters of interference-flow(IF).

关键词： delay mobile edge computing random routing stochastic network calculus

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国有企业数字化转型的赋能机制与外部效应

经济管理 2024年第4期46卷 80-95页

作者：王勇窦斌王悦清华大学社会科学学院北京100084 中国企业改革与发展研究会北京100053

国有企业的数字化转型如何提升其自身运营效率,对整体经济运行产生的影响效应如何,是推进国有企业数字化转型需要回答的关键问题。对此,本文基于Word2Vec神经网络语言模型,构造了国有企业数字化转型的量化指标,并结合国有上市企业的经... 详细信息

国有企业的数字化转型如何提升其自身运营效率,对整体经济运行产生的影响效应如何,是推进国有企业数字化转型需要回答的关键问题。对此,本文基于Word2Vec神经网络语言模型,构造了国有企业数字化转型的量化指标,并结合国有上市企业的经营数据,实证检验了国有企业数字化转型的赋能机制和外部效应。研究发现:国有企业的数字化转型可以通过优化人力资本、提升管理能力、增强创新能力三个渠道促进其生产效率的提升,呈现出显著的赋能效应;国有企业数字化转型对整体经济的外部效应体现在对其他企业转型的溢出效应,以及应对宏观经济冲击的稳定器效应。本文还发现,通过提高国有企业的财务柔性和适应性创新能力,以及加强管理层激励和加大政府补助力度,可以实现更好的转型效果。上述发现不仅从量化的角度检验了国有企业数字化转型的自身赋能效应和外部经济效应,论证了加快国有企业数字化转型的必要性,也明确了国有企业数字化转型的具体途径,为出台相关政策提供了理论依据。

关键词：国有企业数字化转型 Word2Vec模型溢出效应稳定器效应