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Geology and Geochemistry of K-feldspar Veins in Lamprophyre at the Zhenyuan Gold Deposit,Yunnan,Southwest China:Implications for Gold Mineralization

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 104-116页

作者： ZHANG Huichao CHAI Peng ZHANG Hongrui ZHOU Limin HOU Zengqian Key Laboratory of Submarine Geosciences Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Key Laboratory of Marine Hazards Forecasting Ministry of Natural ResourcesHohai UniversityNanjing 210024China National Research Center for Geoanalysis Beijing 100037China

Lamprophyres typically appear in hydrothermal gold *** relationship between lamprophyres and gold deposits is investigated *** researchers suggest that the emplacement of lamprophyres triggers gold mineralization,whereas others hypothesize that the formation of lamprophyres increases the fertility of mantle sources and ore-forming fluids.K-feldspar veins,with ages between those of lamprophyres and gold deposits,appear in lamprophyres in ***,K-feldspar veins are ideal for investigating the relationship between lamprophyres and gold *** in K-feldspar veins has lower Mg#,Ni,and Cr contents and higher TiO2,Li,Ba,Sr,Sc,Zr,Nb,and Cs contents than phlogopite in *** in-situ Sr isotopic values of apatites(0.7063–0.7066)in K-feldspar veins are within the range for apatites(0.7064–0.7078)from *** large-ion lithophile element concentrations and low Nb and Ta concentrations in phlogopite from lamprophyres,in addition to high(87Sr/86Sr)i values of apatite(0.7064–0.7078),indicate that the magma parental to these phlogopite and apatite crystals is derived from an enriched *** veins are genetically correlated with lamprophyres,whereas sulfide mineral assemblage and trace element compositions of pyrite in K-feldspar veins suggest that K-feldspar veins in lamprophyres are not directly related to gold mineralization of the Zhenyuan deposit.

关键词： lamprophyre K-feldspar vein apatite Sr isotope gold Zhenyuan deposit Yunnan

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Anti-Inflammatory Glycosaminoglycan Oligosaccharides from Colwellia psychrerythraea 34H Capsule:Synthesis and Biological Evaluation

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CCS Chemistry 2024年第7期6卷 1698-1711页

作者： Zhongtang Li Xiaoyu Sun Yuchao Wang Ao Sun Linbo Fu Tongtong Geng Zihui Zhang Ximin Lv Qian Wang Jing Wang Baodi Gou Xiangbao Meng Zhongjun Li State Key Laboratory of natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing 100191

Capsular polysaccharides(CPS)of Colwellia psychrerythraea 34H consist of linear tetrasaccharides repeating units in a glycosaminoglycan-like *** biological function is likely involved in the cold adaptation of microbial *** low availability of these glycosaminoglycan structures greatly limits the study of their functions and biological ***,an efficient semisynthetic strategy for CPS tetrasaccharide derivatives is achieved by using disaccharide units degraded from hyaluronic *** new synthetic process is suitable for largescale preparation,and several rare tetrasaccharide derivatives containing GalA-GalNAc were readily obtained in high *** evaluation of their anti-inflammatory effects demonstrated that these CPS tetrasaccharides effectively attenuated the lipopolysaccharide-induced sepsis and acute lung injury by decreasing macrophage infiltration and secretion of microphage-related cytokines in *** these results suggest that this new type of CPS tetrasaccharide can be developed as an anti-inflammation agent.

关键词： glycosaminoglycan oligosaccharide glycosylation anti-inflammatory agent acute lung injury

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Facile semisynthesis of histone H3 enables nucleosome probes for investigation of histone H3K79 modifications

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Chinese Chemical Letters 2024年第10期35卷 347-350页

作者： Kun Zou Yihang Xiao Jinyu Yang Mingxuan Wu Department of Chemistry Zhejiang University Department of Chemistry School of Science Westlake University Institute of natural sciences Westlake Institute for Advanced Study

Histone H3K79 modifications are essential to regulate chromatin structure and gene transcription, but understanding of the molecular mechanisms is limited. Because H3K79 is at globular domain, short histone peptide cannot mimic H3K79 in chromatin. Instead, reconstituted nucleosome-based chemical tools are ideally used to investigate H3K79 modifications. In consequence, H3K79-modified histone H3 with additional chemical handles are required, but such synthesis is challenging and laborious. Here we report a facile semisynthesis method that enables multifunctional histone H3 readily available. H3K79-containing fragment is short for straight peptide synthesis that was later ligated to recombinant expressed H3 fragments for full-length product in large scale. As a result, nucleosomes with H3K79 modifications as well as photo-reactive group and affinity tag were obtained to investigate potential binding proteins. We believe this method that enhances synthetic accessibility of nucleosome probes will accelerate understanding of the underexplored H3K79 modifications.

关键词： H3K79 modifications Histone Methylation Nucleosome probes Semisynthesis Succinylation

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A generalization of Banach's lemma and its applications to perturbations of bounded linear operators

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 363-369页

作者： WANG Zi DING Jiu WANG Yu-wen school of Mathematics sciences Harbin Normal UniversityHarbin 150025China school of Mathematics and natural sciences The University of Southern MississippiHattiesburg MS 39406-5043USA Academic Committee Harbin Institute of PetroleumHarbin 150027China

Let X be a Banach space and let P:X→X be a bounded linear *** an algebraic inequality on the spectrum of P,we give a new sufficient condition that guarantees the existence of(I-P)^(-1) as a bounded linear operator on X,and a bound on its spectral radius is also *** generalizes the classic Banach *** apply the result to the perturbation analysis of general bounded linear operators on X with commutative perturbations.

关键词： Banach lemma spectral radius generalized inverse perturbation analysis

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Hyperspectral remote sensing identification of marine oil emulsions based on the fusion of spatial and spectral features

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Acta Oceanologica Sinica 2024年第3期43卷 139-154页

作者： Xinyue Huang Yi Ma Zongchen Jiang Junfang Yang school of Geography and Marine Science Nanjing UniversityNanjing 210023China First Institute of oceanography Ministry of Natural ResourcesQingdao 266061China Marine Telemetry Technology Innovation Center Ministry of Natural ResourcesQingdao 266061China Harbin Institute of Technology Harbin 150001China China University of Petroleum(East China) Qingdao 266061China

Marine oil spill emulsions are difficult to recover,and the damage to the environment is not easy to *** use of remote sensing to accurately identify oil spill emulsions is highly important for the protection of marine ***,the spectrum of oil emulsions changes due to different water *** remote sensing and deep learning can use spectral and spatial information to identify different types of oil ***,hyperspectral data can also cause information redundancy,reducing classification accuracy and efficiency,and even overfitting in machine learning *** address these problems,an oil emulsion deep-learning identification model with spatial-spectral feature fusion is established,and feature bands that can distinguish between crude oil,seawater,water-in-oil emulsion(WO),and oil-in-water emulsion(OW)are filtered based on a standard deviation threshold–mutual information *** oil spill airborne hyperspectral data,we conducted identification experiments on oil emulsions in different background waters and under different spatial and temporal conditions,analyzed the transferability of the model,and explored the effects of feature band selection and spectral resolution on the identification of oil *** results show the following.(1)The standard deviation–mutual information feature selection method is able to effectively extract feature bands that can distinguish between WO,OW,oil slick,and *** number of bands was reduced from 224 to 134 after feature selection on the Airborne Visible Infrared Imaging Spectrometer(AVIRIS)data and from 126 to 100 on the S185 data.(2)With feature selection,the overall accuracy and Kappa of the identification results for the training area are 91.80%and 0.86,respectively,improved by 2.62%and 0.04,and the overall accuracy and Kappa of the identification results for the migration area are 86.53%and 0.80,respectively,improved by 3.45%and 0.05.(3)The oil emulsion id

关键词： oil emulsions identification hyperspectral remote sensing feature selection convolutional neural network(CNN) spatial-temporal transferability

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From concept to commercialization:A review of tubular solid oxide fuel cell technology

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Journal of Energy Chemistry 2024年第10期97卷 79-109页

作者： Ruyan Chen Yuan Gao Jiutao Gao Huiyu Zhang Martin Motola Muhammad Bilal Hanif Cheng-Xin Li State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and Engineering Xi'an Jiaotong University Department of Inorganic Chemistry Faculty of Natural Sciences Comenius University Bratislava

The reduced sealing difficulty of tubular solid oxide fuel cells(SOFCs) makes the stacking of tubular cell groups relatively easy,and the thermal stress constraints during stack operation are smaller,which helps the stack to operate stably for a long *** special design of tubular SOFC structures can completely solve the problem of high-temperature sealing,especially in the design of multiple single-cell series integrated into one tube,where each cell tube is equivalent to a small electric stack,with unique characteristics of high voltage and low current output,which can significantly reduce the ohmic polarization loss of tubular *** paper provides an overview of typical tubular SOFC structural designs both domestically and *** on the geometric structure of tubular SOFCs,they can be divided into bamboo tubes,bamboo flat tubes,single-section tubes,and single-section flat tube ***,this article provides an overview of commonly used materials and preparation methods for tubular SOFCs,including commonly used materials and preparation methods for support and functional layers,as well as a comparison of commonly used preparation methods for microtubule SOFCs,It introduced the three most important parts of building a fuel cell stack:manifold,current collector,and ceramic adhesive,and also provided a detailed introduction to the power generation systems of different tubular SOFCs,Finally,the development prospects of tubular SOFCs were discussed.

关键词： Geometric structure Preparation methods Stack Support material Tubular solid oxide fuel cell

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Height-diameter models for King Boris fir(Abies borisii regis Mattf.) and Scots pine(Pinus sylvestris L.) in Olympus and Pieria Mountains, Greece

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Journal of Mountain Science 2024年第5期21卷 1475-1490页

作者： Dimitrios I.RAPTIS Dimitra PAPADOPOULOU Angeliki PSARRA Athanasios A.FALLIAS Aristides G.TSITSANIS Vassiliki KAZANA Renewable natural Resource Management and Bioeconomy Laboratory Department of Forest and Natural Environment SciencesInternational Hellenic University66100 DramaGreece

In forest science and practice, the total tree height is one of the basic morphometric attributes at the tree level and it has been closely linked with important stand attributes. In the current research, sixteen nonlinear functions for height prediction were tested in terms of their fitting ability against samples of Abies borisii regis and Pinus sylvestris trees from mountainous forests in central Greece. The fitting procedure was based on generalized nonlinear weighted regression. At the final stage, a five-quantile nonlinear height-diameter model was developed for both species through a quantile regression approach, to estimate the entire conditional distribution of tree height, enabling the evaluation of the diameter impact at various quantiles and providing a comprehensive understanding of the proposed relationship across the distribution. The results clearly showed that employing the diameter as the sole independent variable, the 3-parameter Hossfeld function and the 2-parameter N?slund function managed to explain approximately 84.0% and 81.7% of the total height variance in the case of King Boris fir and Scots pine species, respectively. Furthermore, the models exhibited low levels of error in both cases(2.310m for the fir and 3.004m for the pine), yielding unbiased predictions for both fir(-0.002m) and pine(-0.004m). Notably, all the required assumptions for homogeneity and normality of the associated residuals were achieved through the weighting procedure, while the quantile regression approach provided additional insights into the height-diameter allometry of the specific species. The proposed models can turn into valuable tools for operational forest management planning, particularly for wood production and conservation of mountainous forest ecosystems.

关键词： Generalized nonlinear weighted regression Monte Carlo cross-validation Mountainous ecosystems Quantile regression Central Greece

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Enhancing SAEAs with unevaluated solutions:a case study of relation model for expensive optimization

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Science China(Information sciences) 2024年第2期67卷 41-58页

作者： Hao HAO Xiaoqun ZHANG Aimin ZHOU Institute of natural sciences Shanghai Jiao Tong University Shanghai Frontiers Science Center of Molecule Intelligent Syntheses school of Computer Science and Technology East China Normal University

Surrogate-assisted evolutionary algorithms(SAEAs) hold significant importance in resolving expensive optimization problems. Extensive efforts have been devoted to improving the efficiency of SAEAs through the development of proficient model-assisted solution selection methods, which, however, first requires generating high-quality solutions. The fundamental paradigm of evaluating a limited number of solutions in each generation within SAEAs reduces the variance of adjacent populations, thereby affecting the quality of offspring solutions. This is a frequently encountered issue yet receives little attention. To address the issue, this paper presents a framework using unevaluated solutions to enhance the efficiency of *** surrogate model is employed to identify high-quality solutions for the direct generation of new solutions without evaluation. To ensure dependable selection, we have introduced two tailored relation models to select the optimal solution and the unevaluated population. A comprehensive experimental analysis is performed on two test suites, which showcases the superiority of the relation model over regression and classification models in the solution selection phase. Furthermore, the surrogate-selected unevaluated solutions with high potential have been shown to enhance the efficiency of the algorithm significantly.

关键词： expensive optimization unevaluated solutions relation model surrogate-assisted evolutionary algorithm

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An eikonal equation-based earthquake location method by inversion of multiple phase arrivals

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Science China Earth sciences 2024年第6期67卷 1802-1817页

作者： Gaoyue LAO Dinghui YANG Shaolin LIU Guiju DONG Wenshuai WANG Kui LIU National Institute of natural Hazards Ministry of Emergency Management of ChinaBeijing 100085China school of Earth sciences Yunnan UniversityKunming 650091China Department of Mathematical sciences Tsinghua UniversityBeijing 100084China school of Mathematics and Statistics Ningxia UniversityYinchuan 750021China

The precise determination of earthquake location is the fundamental basis in seismological community,and is crucial for analyzing seismic activity and performing seismic *** arrivals are generally used to practically determine earthquake ***,first-arrival traveltimes are not sensitive to focal ***,they cannot accurately constrain focal *** improve the accuracy,researchers have analyzed the depth phases of earthquake *** traveltimes of depth phases are sensitive to focal depths,and the joint inversion of depth phases and direct phases can be implemented to potentially obtain accurate earthquake ***,researchers can determine earthquake locations in layered *** layered models can only represent the first-order feature of subsurface structures,the advantages of joint inversion are not fully explored if layered models are *** resolve the issue of current joint inversions,we use the traveltimes of three seismic phases to determine earthquake locations in heterogeneous *** three seismic phases used in this study are the first P-,sPg-and *** calculate the traveltimes of the three seismic phases by solving an eikonal equation with an upwind difference scheme and use the traveltimes to determine earthquake *** verify the accuracy of the earthquake location method by the inversion of three seismic phases,we take the 2021 M_(S)6.4 Yangbi,Yunnan earthquake as an example and locate this earthquake using synthetic and real seismic *** tests demonstrate that the eikonal equation-based earthquake location method,which involves the inversion of multiple phase arrivals,can effectively improve earthquake location accuracy.

关键词： Earthquake location Eikonal equation Fast marching method Heterogeneous model

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Dieback of managed spruce stands in western Germany promotes beetle diversity

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Journal of Forestry Research 2024年第3期35卷 55-71页

作者： Eva Plath Chantal Trauth Jan Gerhards Laura Griebel Klaus Fischer Department Biology Institute of Integrated Natural SciencesKoblenz-Landau University56070 KoblenzGermany

Biodiversity loss is a significant problem at a global scale and may be amplified by climate *** recent years,coniferous forests have had substantial die-back across Europe due to drought and subsequent bark-beetle *** many studies on the consequences of disturbance and subsequent management have focused on natural stands,management implications for managed spruce stands are not well understood,even though such stands are widespread throughout *** this study,beetle taxonomy,conservation value,and community com-position are compared among spruce plantations and four post-disturbance management approaches:standing dead-wood,lying deadwood,clear cuts,and long-term *** and community composition differed significantly among management categories,while different beetle fami-lies responded *** spruce stands harbored the lowest beetle diversity while the highest taxonomic diver-sity and conservation value was on clear cuts and stands with lying or standing *** proportion of forest specialists was highest in successional *** summary,different forest management categories harbored distinct beetle communities at the family-,species-,and ecological guild ***,post-disturbance management should consider the landscape scale and include different management *** enhances landscape heterogeneity and thus overall biodiversity but could also mitigate negative impacts of natural disturbances on ecosystem services.

关键词： Bark-beetle outbreak Forest dieback Spruce Deadwood Nature conservation Beetle biodiversity-Coleoptera Coniferous forests

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