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Understanding the rapid spread of antimicrobial resistance genes mediated by IS26

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mLife 2024年第1期3卷 101-109页

作者： Na Tang Dawei Wei Yuan Zeng Gang Zhang chao Wang Jie feng Yuqin Song State Key Laboratory of Microbial Resources Institute of MicrobiologyChinese Academy of SciencesBejingChina College of Life Science University of Chinese Academy of SciencesBeijingChina

Insertion sequences(ISs)promote the transmission of antimicrobial resistance genes(ARGs)across bacterial ***,their contributions and dynamics during the transmission of resistance remain *** this study,we selected is26 as a representative transposable element to decipher the relationship between ISs and ARGs and to investigate their transfer features and transmission *** retrieved 2656 translocatable IS26-bounded units with ARGs(tiS26-bUs-ARGs)in complete bacterial genomes from the NCBI RefSeq *** total,124 ARGs spanning 12 classes of antibiotics were detected,and the average contribution rate of IS26 to these genes was 41.2%.We found that IS26-bounded units(IS26-bUs)mediated extensive ARG dissemination within the bacteria of the Gammaproteobacteria class,showing strong transfer po-tential between strains,species,and even *** Is26-bUs expanded in bacterial populations over time,and their temporal expansion trend was significantly correlated with antibiotic *** wide dissemination could be due to the nonspecific target site preference of ***,we experimentally confirmed that the introduction of a single copy of is26 could lead to the formation of a composite transposon mediating the transmission of“passenger”*** observations extend our knowledge of the IS26 and provide new insights into the mediating role of ISs in the dissemination of antibiotic resistance.

关键词： antibiotic consumption antibiotic resistance genes horizontal gene transfer insertion sequence IS26

Dielectric Constant Calculation of Poly(vinylidene fluoride)Based on Finite Field and Density Functional Theory

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Chinese Journal of Polymer Science 2024年第5期42卷 655-662,I0009页

作者： Yong-Zhi Lin Lu-Kun feng Ya-Dong Li chao-Fan Chang Cai-Zhen Zhu Ming-Liang Wang Jian Xu College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen518055China Chengdu Institute of Organic Chemistry Chinese Academy of SciencesChengdu610041China

In this study,we proposed a novel method that integrates density functional theory(DFT)with the finite field method to accurately estimate the polarizability and dielectric constant of *** approach effectively accounts for the influence of electronic and geometric conformation changed on the dielectric *** validated our method using polyethylene(PE)and polytetrafluoroethylene(PTFE)as benchmark materials,and found that it reliably predicted their dielectric ***,we explored the impact of conformation variations in poly(vinylidene fluoride)(PVDF)on its dielectric constant and *** resulting dielectric constants ofα-andγ-PVDF(3.0)showed excellent agreement with crystalline PVDF in *** findings illuminate the relationship between PVDF’s structural properties and its electrical behavior,offering valuable insights for material design and applications.

关键词： Dielectric constant PVDF Finite field DFT

Geochemical Anomalies Identified by Multifractal Modeling: Implications for Mineral Exploration in the Ziyoutun Cu-Au District, Jilin Province, China

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Acta Geologica Sinica(English Edition) 2024年第4期98卷 1111-1124页

作者： ma Huchao WANG Da BAI feng LIU Meng GONG Anzhou HU Haiyan State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences and ResourcesChina University of GeosciencesBeijing 100083China School of Gemmology China University of GeosciencesBeijing 100083China Guizhou Nengda Electric Power Design Co. Ltd.Guiyang 550002China Chongqing Chuandongnan Survey&Design Institute Co. Ltd.Chongqing 400038China

The Ziyoutun Cu-Au district is located in the Jizhong–Yanbian Metallogenic Belt and possesses excellent prospects. However, the thick regolith and complex tectonic settings present challenges in terms of detecting and decomposition of weak geochemical anomalies. To address this challenge, we initially conducted a comprehensive analysis of 1:10,000-scale soil geochemical data. This analysis included multivariate statistical techniques, such as correlation analysis, R-mode cluster analysis, Q–Q plots and factor analysis. Subsequently, we decomposed the geochemical anomalies, identifying weak anomalies using spectrum-area modeling and local singularity analysis. The results indicate that the assemblage of Au-Cu-Bi-As-Sb represents the mineralization at Ziyoutun. In comparison to conventional methods, spectrumarea modeling and local singularity analysis outperform in terms of identification of anomalies. Ultimately, we considered four specific target areas(AP01, AP02, AP03 and AP04) for future exploration, based on geochemical anomalies and favorable geological factors. Within AP01 and AP02, the geochemical anomalies suggest potential mineralization at depth, whereas in AP03 and AP04 the surface anomalies require additional geological investigation. Consequently, we recommend conducting drilling, following more extensive surface fieldwork, at the first two targets and verifying surface anomalies in the last two targets. We anticipate these findings will significantly enhance future exploration in Ziyoutun.

关键词： geochemical anomalies multivariate statistical analysis spectrum-area model local singularity analysis mineral prospecting Jilin Province

A process insight into production of ethyl levulinate via a stepwise fractionation

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Journal of Bioresources and Bioproducts 2024年第2期9卷 233-242页

作者： Yan ma Hongxiao Wang Ziyang Wu Weihong Tan Guodong feng Jianchun Jiang Institute of Chemical Industry of Forest Products Chinese Academy of ForestryNanjing 210042China Jiangsu Province Key Lab.of Biomass Energy and material Nanjing 210042China National Engineering Lab.for Biomass Chemical Utilization Nanjing 210042China Co-Innovation Center of Efficient Processing and Utilization of Forest Resources Nanjing Forestry UniversityNanjing 210037China

Ethyl levulinate(EL)is a key biomass-derived compounds due to its socio-economic benefits for the synthesis of commodity ***,we proposed an efficient one-step bamboo conversion to EL in ethanol,and a novel stepwise fractionation to purify EL and lignocellulose degradation products.A proton acid,due to its high catalytic efficiency,yielded 26.65%EL in 120 min at 200℃.The productions of ethyl glucoside and 5-ethoxymethylfurfural were analyzed in terms of by-products *** the best of our knowledge,there is no single report on catalyst for one step synthesis of EL directly from bamboo,as well as a stepwise fractionation to purify *** to similar physiochemical properties in each fraction,the platform molecules could broaden a new paradigm of bamboo biomass utilization for renewable energy and value-added *** addition,glucose,ethyl glucoside,corn starch,and microcrystalline cellulose were also investigated as substrates,so that the reaction intermediates of this one-pot procedure were identified and a possible reaction mechanism was proposed.

关键词： Ethyl levulinate Liquefaction Biomass Ethanol By-products

Case study on the mechanics of NPR anchor cable compensation for large deformation tunnel in soft rock in the Transverse Mountain area,China

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Journal of Central South University 2024年第6期31卷 2054-2069页

作者： LI Yong ZHENG Jing HUO Shu-sen WANG feng-nian HE man-chao TAO Zhi-gang College of Geoscience and Surveying Engineering China University of Mining and Technology(Beijing)Beijing 100083China State Key Labortaory for Fine Exploration and Intelligent Development of Coal Resources China University of Mining and Technology(Beijing)Beijing 100083China State Key Laboratory for Tunnel Engineering China University of Mining and Technology(Beijing)Beijing 100083China Shanxi Provincial Transportation Technology Research and Development Co.Ltd. Key Laboratory of Highway Construction and Maintenance Technology in Loess AreaTransportation IndustryTaiyuan 030000China

A study was conducted to analyze the deformation mechanism of strongly weathered quartz schist in the Daliangshan Tunnel,located in the western Transverse Mountain area.A large deformation problem was experienced during the tunnel *** mitigate this problem,a support system was designed incorporating negative Poisson ratio(NPR)anchor cables with negative Poisson ratio *** model experiments,field experiments,and numerical simulation experiments were conducted to investigate the compensation mechanical behavior of NPR anchor *** large deformations of soft rocks in the Daliangshan Tunnel are caused by a high ground stress,a high degree of joint fracture development,and a high degree of surrounding rock fragmentation.A compensation mechanics support system combining long and short NPR anchor cables was suggested to provide sufficient counter-support force(approximately 350 kN)for the surrounding rock inside the *** the NPR anchor cable support system with the original support system used in the Daliangshan tunnel showed that an NPR anchor cable support system,combining cables of 6.3 m and 10.3 m in length,effectively prevented convergence of surrounding rock deformation,and the integrated settlement convergence value remained below 300 *** study provides an effective scientific basis for resolving large deformation problems in deeply buried soft rocks in western transverse mountain areas.

关键词： soft rock large deformation NPR anchor cable physical model numerical simulation compensation mechanics

Development of a Front End Array for Broadband Phased Array Receiver

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Research in Astronomy and Astrophysics 2024年第4期24卷 60-70页

作者： Kai Wang Liang Cao Jun ma Xue-feng Duan Hao Yan mao-Zheng Chen Yun-Wei Ning Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 8300lChina University of the Chinese Academy of Sciences Beijing 100049China Xinjiang Key Laboratory of Microwave Technology Urumqi 830011China

The receiver is a signal receiving device placed at the focus of the *** order to improve the observation efficiency,the concept of phased array receiver has been proposed in recent years,which places a small phased array at the focal plane of the reflector,and flexible pattern and beam scanning functions can be achieved through a beamforming *** combined with the element multiplexing,all beams within the entire field of view can be observed simultaneously to achieve continuous sky *** article focuses on the front-end array of phased array receiver at 0.7-1.8 GHz for QiTai Telescope,and designs a Vivaldi antenna array of PCB structure with dual line *** polarization antenna is designed to arrange in a rectangle manner by 11×*** on the simulation results of the focal field,32,18,and eight elements were selected to form one beam at 0.7,1.25,and1.8 *** analog beamforming network was constructed,and the measured gains of axial beam under uniform weighting were 19.32,13.72,and 15.22 *** the beam scanning method of reflector antenna,the pattern test of different position element sets required for PAF beam scanning was carried out under independent *** pattern optimization at 1.25 GHz was carried out by weighting method of conjugate field *** with uniform weighting,the gain,sidelobe level,and main beam direction under conjugate field matching have been *** the above test and simulation results are slightly different,which is related to the passive array and laboratory testing condition,the relevant work has accumulated experience in the development of the front-end array for the phased array receiver,and has good guiding significance for future performance verification after the array is installed on the telescope.

关键词： telescopes instrumentation:detectors techniques:radar astronomy

Climate change filtered out resource-acquisitive plants in a temperate grassland in Inner Mongolia,China

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Science China(Life Sciences) 2024年第2期67卷 403-413页

作者： Heying Jing Xingshuo Xiong feng Jiang Xucai Pu Wenhong ma Daijiang Li Zhongling Liu Zhiheng Wang Institute of Ecology and Key Laboratory for Earth Surface Processes of the Ministry of Education College of Urban and Environmental SciencesPeking UniversityBeijing 100871China Ministry of Education Key Laboratory of Ecology and Resource Use of the Mongolian Plateau School of Ecology and EnvironmentInner Mongolia UniversityHohhot 010021China Department of Biological Sciences Louisiana State UniversityBaton RougeLA 70803USA

Global climate change has led to the decline of species and functional diversity in ecosystems,changing community composition and ecosystem ***,we still know little about how species with different resource-use strategies(different types of resource usage and plant growth of plants as indicated by the spectrum of plant economic traits,including acquisitive resource-use strategy and conservative resource-use strategy)would change in response to climate change,and how the changes in the diversity of species with different resource-use strategies may influence community-level ***,using long-term(1982–2017)observatory data in a temperate grassland in Inner Mongolia,we investigated how climate change had affected the species richness(SR)and functional richness(FRic)for the whole community and for species with different resource-use ***,based on data for four traits representing leaf economics spectrum(leaf carbon concentration,leaf nitrogen concentration,leaf phosphorus concentration,and specific leaf area),we divided 81 plant species appearing in the grassland community into three plant functional types representing resource-acquisitive,medium,and resource-conservative *** then analyzed the changes in community-level productivity in response to the decline of SR and FRic at the community level and for different resource-use *** found that community-level SR and FRic decreased with drying climate,which was largely driven by the decline of diversity for resource-acquisitive ***,community-level productivity remained stable because resource-conservative species dominating this grassland were barely affected by climate *** study revealed distinctive responses of species with different resource-use strategies to climate change and provided a new approach based on species functional traits for predicting the magnitude and direction of climate change effects on ecosystem functions.

关键词： biodiversity ecological strategy functional diversity functional trait long-term change species diversity

Progress in systematics and biogeography of Orchidaceae

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Plant Diversity 2024年第4期46卷 425-434页

作者： Yajun Wang Hanchen Wang chao Ye Zhiping Wang Chongbo ma Dongliang Lin Xiaohua Jin State Key Laboratory of Plant Diversity and Specialty Crops Institute of Botanythe Chinese Academy of SciencesBeijing 100093China University of Chinese Academy of Sciences Beijing 100093China China National Botanical Garden Beijing 100093China

Orchidaceae are one of the largest families of angiosperms in terms of species *** the last decade,numerous studies have delved into reconstructing the phylogenetic framework of Orchidaceae,leveraging data from plastid,mitochondrial and nuclear *** studies have provided new insights into the systematics,diversification and biogeography of Orchidaceae,establishing a robust foundation for future ***,pronounced controversies persist regarding the precise placement of certain lineages within these phylogenetic *** address these discrepancies and deepen our understanding of the phylogenetic structure of Orchidaceae,we provide a comprehensive overview and analysis of phylogenetic studies focusing on contentious groups within Orchidaceae since 2015,delving into discussions on the underlying reasons for observed topological *** also provide a novel phylogenetic framework at the subtribal ***,we examine the tempo and mode underlying orchid species diversity from the perspective of historical biogeography,highlighting factors contributing to extensive ***,we delineate avenues for future research aimed at enhancing our understanding of Orchidaceae phylogeny and diversity.

关键词： Diversification Orchid phylogenetics Phylogenetic conflicts Biogeography Taxonomy

Leaching behavior and microstructure of phosphorus in converter slag

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Journal of Iron and Steel Research(International) 2024年第7期31卷 1646-1660页

作者： chao-gang Zhou Jin-yue Li Qing-gong Chen Yin-ye Yang Wei Gong Li-qun Ai Shu-huan Wang Bei-yue ma College of Metallurgy and Energy North China University of Science and TechnologyTangshan 063210HebeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081HubeiChina College of materials Science and Engineering Guizhou Minzu UniversityGuiyang 550025GuizhouChina School of materials and Architectural Engineering Guizhou Normal UniversityGuiyang 550025GuizhouChina School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina

Converter slag is a by-product of the steelmaking process and contains a large amount of Ca,Fe,P and other *** the phosphorus in the converter slag can be effectively extracted,the resulting phosphorus can be used as a phosphate *** in converter slag is mainly enriched in 2CaO·SiO_(2)-3CaO·P_(2)O_(5)(C_(2)S-C_(3)P)solid solution and is easily dissolved in ***,acid leaching method was used to dissolve the solid solution to extract phosphorus in converter slag,so as to realize the recycling of phosphorus resources in converter *** leaching behavior of three actual converter slags from different steel mills in acid leaching solutions composed of citric acid,sodium hydroxide,hydrochloric acid and deionized water was studied by X-ray diffraction,scanning electron microscopy combined with energy dispersive spectrometry,Fourier transform infrared spectroscopy and Raman spectroscopy to reveal the change in object image structure as well as SiO_(4) and PO_(4) tetrahedron before and after acid *** results show that only a small amount of phosphorus in converter slag with too low basicity is enriched in C_(2)S-C_(3)P solid solution,resulting in poor leaching *** the converter slag has a high basicity,the removal effect of phosphorus is 70.64%-81.88%.In addition,when the basicity of converter slag is roughly the same,the dephosphorization effect of slag with high FeO content is relatively *** acid leaching will cause depolymerization behavior of SiO_(4) and PO_(4) tetrahedron,so that the mole fraction of Q0(Si)(asymmetric stretching vibration of Si-O bond in SiO_(4) tetrahedron with bridge oxygen number of 0)and NBO/Si(non-bridging oxygen in silicate tetrahedra)will ***-containing solids can be obtained from the solution after acid leaching through static precipitation,and the solids have the potential to make phosphate fertilizers.

关键词： Dephosphorization converter slag Acid leaching Phosphorus Solid solution Slag structure