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Cryptic diversity and rampant hybridization in annual gentians on the Qinghai-Tibet Plateau revealed by population genomic analysis

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Plant Diversity 2024年第2期46卷 194-205页

作者： Peng-Cheng Fu Qiao-Qiao guo Di chang Qing-Bo Gao shan-shan Sun School of Life Science Luoyang Normal UniversityLuoyang 471934PR China Key Laboratory of Adaptation and Evolution of Plateau Biota Northwest Institute of Plateau BiologyChinese Academy of SciencesXining 810001PR China

Understanding the evolutionary and ecological processes involved in population differentiation and speciation provides critical insights into biodiversity formation. In this study, we employed 29,865 single nucleotide polymorphisms(SNPs) and complete plastomes to examine genomic divergence and hybridization in Gentiana aristata, which is endemic to the Qinghai-Tibet Plateau(QTP) region. Genetic clustering revealed that G. aristata is characterized by geographic genetic structures with five clusters(West, East, Central, South and North). The West cluster has a specific morphological character(i.e., blue corolla) and higher values of FSTcompared to the remaining clusters, likely the result of the geological barrier formed by the Yangtze River. The West cluster diverged from the other clusters in the Early Pliocene;these remaining clusters diverged from one another in the Early Quaternary. Phylogenetic reconstructions based on SNPs and plastid data revealed substantial cyto-nuclear conflicts. Genetic clustering and D-statistics demonstrated rampant hybridization between the Central and North clusters,along the Bayankala Mountains, which form the geological barrier between the Central and North clusters. Species distribution modeling demonstrated the range of G. aristata expanded since the Last Interglacial period. Our findings provide genetic and morphological evidence of cryptic diversity in G. aristata, and identified rampant hybridization between genetic clusters along a geological *** findings suggest that geological barriers and climatic fluctuations have an important role in triggering diversification as well as hybridization, indicating that cryptic diversity and hybridization are essential factors in biodiversity formation within the QTP region.

关键词： Gentiana aristata Hybrid zone Qinghai-Tibet Plateau Plastome Nuclear SNPs

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Greedy Lattice Paths with General Weights

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2213-2222页

作者： Yin shan chang An Qi ZHENG College of Mathematics Sichuan UniversityChengdu 610065P.R.China

Let{X_(v):v∈Z^(d)}be *** *** S(π)=Σ_(v∈π)X_(v)be the weight of a self-avoiding lattice pathπ.Let M_(n)=max{S(π):πhas length n and starts from the origin}.We are interested in the asymptotics of Mn as n→∞.This model is closely related to the first passage percolation when the weights{X_(v):v∈Z^(d)}are non-positive and it is closely related to the last passage percolation when the weights{X_(v):v∈Z^(d)}are *** general weights,this model could be viewed as an interpolation between first passage models and last passage ***,this model is also closely related to a variant of the position of right-most particles of branching random *** the two assumptions that∃α>0,E(X_(0)^(+))^(d)(log^(+)X_(0)^(+))^(d+α)0,E(X_(0)^(+))^(d)(log^(+)X_(0)^(+))^(d+α)<+∞and that E[(X_(0)^(−))^(4)]<+∞,we prove that M_(n)/n converges to the same constant M almost surely as n tends to infinity.

关键词： Last passage percolation first passage percolation greedy lattice path

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Bevacizumab rescue therapy extends the survival in patients with recurrent malignant glioma

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Chinese Journal of Cancer Research 2013年第2期25卷 206-211页

作者： Lin-Bo Cai Juan Li Ming-Yao Lai chang-guo shan Zong-De Lian Wei-Ping Hong Jun-Jie Zhen Qing Zhou Li-Chao Wang Department of Oncology Guangdong 999 Brain Hospital

Objective： We retrospectively studied the efficacy of bevacizumab as salvage therapy for recurrent malignant glioma with a focus on the overall survival （OS）. Methods： Patients who received a therapy other than surgery for recurrent malignant glioma were included. Efficacy was evaluated using MRI. Neurological function was evaluated using the Response Assessment in Neuro-Oncology （RANO）. The survival rate was calculated using the Kaplan-Meier method. Results： Fifty-one patients with recurrent glioma （31 grade Ⅲ, 20 grade Ⅳ） were included. Among them, 22 subjects （43.1%） received bevacizumab. The median OS was 10.2 months （range, 1 to 27 months）. Patients receiving bevacizumab had comparable OS （a median of 9.9 vs. 10.0 months） and similar 6-month survival rate （43% vs. 34%） to those who did not receive bevacizumab. A subgroup analysis failed to notice any significant difference in grade Ⅲ glioma patients receiving bevacizumab vs. those who did not. The median survival was significantly longer at 8.9 months （range, 4 to 13 months） in grade Ⅳ glioma patients receiving bevacizumab than in those who did not （5.6 months, range, 2 to 7 months, P=0.042）. The 6-month survival rate was higher （83 %） in those who received bevacizumab than in those who did not （47 %, P=0.046）. No grade 3/4 adverse events were observed in any patient. Conclusions： Bevacizumab, as a rescue therapy, provides a survival benefit for recurrent grade IV glioma.

关键词： Bevacizumab recurrent malignant glioma

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Effect of cerium alloying on microstructure,texture and mechanical properties of magnesium during cold-rolling process

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Journal of Rare Earths 2024年第5期42卷 1001-1008,I0007页

作者： Zhen Zhang Huanhuan Chen Shiju Cao Jinhua Peng Peng guo chang Long shan Wang chang Chen Yong Wu Ji'an Huang Xiaodong Du Haigen Wei School of Materials Science and Engineering Hefei University of TechnologyHefei230009China NationalLocal Joint Research Center of Non-ferrous Metal Materials and Processing Technology Hefei230009China Laboratory of Nonferrous Metal Material and Processing Engineering of Anhui Province Hefei230009China School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang212003China Institute of Industry and Equipment Technology Hefei University of TechnologyHefei230009China Faculty of Materials Metallurgy and Chemistry Jiangxi University of Science and TechnologyGanzhou341000China

Hot-extrusion and cold-rolling were conducted on Mg-Ce binary alloys to explore the effect of cerium(Ce)on microstructure,texture and mechanical properties of Mg *** addition of Ce results in significant grain refinement both in as-cast and hot-extruded *** basal texture is also weakened after extrusion and an inclined basal texture is formed with Ce *** strength and elongation of the Mg-Ce alloys are improved simultaneously due to such grain refinement and texture weakening *** cold-rolling,plenty of twins are found in the pure Mg and AZ31 plates while grains in the Mg-0.3Ce plate deform more uniformly without lamellar twin ***,Mg-0.3Ce alloys own strong and continuous strain hardening because Ce atoms and Mg-Ce precipitated phases serve as obstacles for dislocation slip.

关键词： Mg-Ce alloys Hot extrusion Cold-rolling Rare earths

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Confluence of asymmetric catalysis and electrosynthesis in sustainable chemical transformations

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Science China Chemistry 2024年第3期67卷 755-758页

作者： Qinglin Zhang Kang Liang chang guo Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry University of Science and Technology of ChinaHefei 230026China

Electrosynthesis has gained widespread recognition for its extraordinary ability to precisely control the redox *** outstanding capability enables the direct conversion of non-functionalized substrates into reactive intermediates by utilizing easily accessible starting materials, eliminating the need for preliminary functionalization procedures and allowing for unconventional bond activations.

关键词： Confluence of asymmetric catalysis and electrosynthesis in sustainable chemical transformations

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Imbalanced rock burst assessment using variational autoencoder-enhanced gradient boosting algorithms and explainability

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Underground Space 2024年第4期17卷 226-245页

作者： shan Lin Zenglong Liang Miao Dong Hongwei guo Hong Zheng Key Laboratory of Urban Security and Disaster Engineering Ministry of EducationBeijing University of TechnologyBeijing 100124China Department of Civil and Environmental Engineering The Hong Kong Polytechnic University(PolyU)Hung HomKowloon 999077Hong KongChina

We conducted a study to evaluate the potential and robustness of gradient boosting algorithms in rock burst assessment,established a variational autoencoder(VAE)to address the imbalance rock burst dataset,and proposed a multilevel explainable artificial intelligence(XAI)tailored for tree-based ensemble *** collected 537 data from real-world rock burst records and selected four critical features contributing to rock burst ***,we employed data visualization to gain insight into the data’s structure and performed correlation analysis to explore the data distribution and feature ***,we set up a VAE model to generate samples for the minority class due to the imbalanced class *** conjunction with the VAE,we compared and evaluated six state-of-theart ensemble models,including gradient boosting algorithms and the classical logistic regression model,for rock burst *** results indicated that gradient boosting algorithms outperformed the classical single models,and the VAE-classifier outperformed the original classifier,with the VAE-NGBoost model yielding the most favorable *** to other resampling methods combined with NGBoost for imbalanced datasets,such as synthetic minority oversampling technique(SMOTE),SMOTE-edited nearest neighbours(SMOTE-ENN),and SMOTE-tomek links(SMOTE-Tomek),the VAE-NGBoost model yielded the best ***,we developed a multilevel XAI model using feature sensitivity analysis,Tree Shapley Additive exPlanations(Tree SHAP),and Anchor to provide an in-depth exploration of the decision-making mechanics of VAE-NGBoost,further enhancing the accountability of treebased ensemble models in predicting rock burst occurrences.

关键词： Gradient boosting VAE Ensemble learning Explainable artificial intelligence(XAI) Rock burst

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Dynamic kinetic stereodivergent transformations of propargylic ammonium salts via dual nickel and copper catalysis

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Chinese Chemical Letters 2024年第8期35卷 265-269页

作者： Ruilong Geng Lingzi Peng chang guo Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry University of Science and Technology of ChinaHefei 230026China

The dynamic kinetic asymmetric transformation of racemic propargylic ammonium salts with prochiral aldimine esters through a stereodivergent propargylation is catalyzed by dual nickel and copper ***,a diverse range of optically activeα-quaternary amino esters were produced via C-N bond cleavage with high reaction efficiency and stereoselectivity(up to>99%ee).By selection of the appropriate pair-wise combination of catalyst configurational isomers,all four possible stereoisomers of the corresponding propargylation products are obtained in high yields with excellent regio-,diastereo-,and enantioselectiv-ities.

关键词： Stereodivergent propargylation Dual catalysis C-N bond cleavage Azaomethine ylides Internal propargylic ammonium salts Excellent stereoselectivity

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Effects of land-use patterns on soil microbial diversity and composition in the Loess Plateau,China

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Journal of Arid Land 2024年第3期16卷 415-430页

作者： ZHANG Jian guo Xiaoqun shan Yujie LU Xin CAO Jianjun College of Geography and Environmental Science Northwest Normal UniversityLanzhou 730070China

In the Loess Plateau of China,land-use pattern is a major factor in controlling underlying biological ***,the process of land-use pattern was accompanied by abandoned lands,potentially impacting soil ***,limited researches were conducted to study the impacts of land-use patterns on the diversity and community of soil microorganisms in this *** study aimed to investigate soil microbial community diversity and composition using high-throughput deoxyribonucleic acid(DNA)sequencing under different land-use patterns(apricot tree land,apple tree land,peach tree land,corn land,and abandoned land).The results showed a substantial difference(Pshannon *** fungal beta-diversity was not considerably impacted by land-use patterns,fungal alpha-diversity indices varied *** relative abundance of Actinobacteriota(34.90%),Proteobacteria(20.65%),and Ascomycota(77.42%)varied in soils with different land-use *** pH exerted a dominant impact on the soil bacterial communities'composition,whereas soil available phosphorus was the main factor shaping the soil fungal communities'*** findings suggest that variations in land-use pattern had resulted in changes to soil properties,subsequently impacting diversity and structure of microbial community in the Loess *** the strong interdependence between soil and its microbiota,it is imperative to reclaim abandoned lands to maintain soil fertility and sustain its function,which will have significant ecological service implications,particularly with regards to soil conservation in ecologically vulnerable areas.

关键词： abandoned lands land-use pattern soil property diversity of soil microbe soil microbial community

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Unbound^(28)O,the heaviest oxygen isotope observed:a cutting-edge probe for testing nuclear models

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Nuclear Science and Techniques 2024年第2期35卷 1-2页

作者： Jian-guo Li Bai-shan Hu Shuang Zhang Fu-Rong Xu School of Physics and State Key Laboratory of Nuclear Physics and TechnologyPeking UniversityBeijing 100871China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Southern Center for Nuclear-Science Theory(SCNT) Institute of Modern PhysicsChinese Academy of SciencesHuizhou 516000China

The beyond-dripline oxygen isotopes^(27,28)O were recently observed at RIKEN,and were found to be unbound decaying into^(24)O by emitting *** unbound feature of the heaviest oxygen isotope,^(28)O,provides an excellent test for stateof-the-art nuclear *** atomic nucleus is a self-organized quantum manybody system comprising specific numbers of protons Z and neutrons N.

关键词： testing quantum system

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High-performance self-powered GaN/PEDOT:PSS hybrid heterojunction UV photodetector for optical communication

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Science China(Technological Sciences) 2024年第2期67卷 608-615页

作者： LI shan LIU Zeng ZHANG MaoLin YANG LiLi guo YuFeng TANG WeiHua College of Integrated Circuit Science and Engineering&National and Local Joint Engineering Laboratory for RF Integration and Micro-Packing Technologies Nanjing University of Posts and TelecommunicationsNanjing 210023China

Self-powered ultraviolet photodetectors(UVPDs)provide great possibility for the next-generation energy conservation optical communication technology;while the high photodetection performance at zero bias is still a tremendous ***,ntype GaN film with Si-doping concentration of~1018cm^(-3)and p-type organic PEDOT:PSS were adopted to construct a planar hybrid heterojunction via the simple spin-coating *** from typical type-Ⅱenergy band alignment and giant photovoltaic effect at GaN/PEDOT:PSS inorganic-organic interface,the fabricated UVPD achieved excellent self-powered photoelectrical properties in dual-band with large R of 0.96 A/W(2.8 A/W),superior D*of 5.7×1012Jones(1.7×10^(13)Jones),prominent EQE of 325%(1371%),high on/off ratio of 9.65×10^(3)(6.15×10^(3))and fast rise/decay time of 60.7/124.5 ms(30.9/26.7 ms)for UVA(UVC)band,as well as outstanding UV/visible rejection ratio and great detection *** as an optical signal receiver,this designed self-powered UVPD decoded a message of“NJUPT”from a simple optical communication *** results open a new avenue for GaN/PEDOT:PSS heterojunction in UV communications and related applications.

关键词： GaN UV photodetector self-powered heterojunction optical communication

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