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Science China Life Sciences 2024年

作者： Jie Li Xing-Chun Li hui-yun gan Yue Zhang Zi-Xuan Guo Yu-Xuan Liu Yong-Qing Lin Liang-Dong Guo State Key Laboratory of Mycology Institute of Microbiology Chinese Academy of Sciences College of Life Sciences University of Chinese Academy of Sciences

Plant diversity significantly impacts ecosystem processes and functions, yet its influence on the community assembly of leaf fungi remains poorly understood. In this study, we investigated leaf epiphytic and endophytic fungal communities in a Chinese subtropical tree species richness experiment, ranging from 1 to 16 species, using amplicon sequencing to target the internal transcribed spacer 1 region of the rDNA. We found that the community assembly of epiphytic and endophytic fungi was predominantly governed by stochastic processes, with a higher contribution of dispersal limitation on epiphytic than on endophytic fungal communities but a higher contribution of selection on endophytic than on epiphytic fungal communities. The plant-epiphytic fungus interaction network was more complex(e.g., more highly connected and strongly nested but less specialized and modularized) than the plant-endophytic fungus interaction network. Additionally,tree species richness was positively correlated with the network complexity and diversity of epiphytic(α-, β-and γ-diversity) and endophytic(β-and γ-diversity) fungi, but was not associated with the contribution of the stochastic and deterministic processes on the community assembly of epiphytic and endophytic fungi. This study highlights that tree species diversity enhances the diversity and network complexity,rather than alters the ecological processes in community assembly of leaf-associated fungi.

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N-Heterocyclic carbene-catalyzed enantioselective(dynamic) kinetic resolutions and desymmetrizations

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Science China Chemistry 2024年第2期67卷 482-511页

作者： Yi Zhang hui Cai Xiuhai gan Zhichao Jin National Key Laboratory of Green Pesticide Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationGuizhou UniversityHuaxi DistrictGuiyang550025China

N-heterocyclic carbene-catalyzed enantioselective kinetic resolutions,dynamic kinetic resolutions,and desymmetrization reactions are systematically *** content is organized according to the activation modes involved i... 详细信息

关键词： N-heterocyclic carbene kinetic resolution dynamic kinetic resolution desymmetrization organocatalysis

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Prediction of suitable water content in granulation of sintering mixture based on Litster's model

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Journal of Iron and Steel Research International 2024年第3期31卷 552-560页

作者： Fang-lei Dai Xiao-hui Fan Xiao-xian Huang Xu-ling Chen Min gan Zhi-yun Ji Zeng-qing Sun School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina

Suitable water content plays a decisive role in the granulation of sintering ***,a method was proposed to predict the suitable water content for effective granulation on the basis of Litster's granulation *** granulation effectiveness of a sintering mixture was predicted by the model,with the allowance error of±10%.The effects of the water absorption properties,particle size composition and content of adhesive particles on the suitable water content were *** results showed that the allowable error of prediction was within±0.5%compared to the experimentally determined suitable water *** an increase in adhesive powder content of mixtures with higher water absorption,the suitable water content increased to achieve similar granulation ***,as the amount of concentrates increased,the suitable water content first increased and then remained *** influence of the water absorption characteristics of the adhesive particles on the suitable water content was less than that of their particle size composition in the mixture.

关键词： Adhesive particle Sintering mixture Granulation effectiveness Suitable water content

Variable projection algorithms with sparse constraint for separable nonlinear models

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Control Theory and Technology 2024年第1期22卷 135-146页

作者： hui-Lang Xu Guang-Yong Chen Si-Qing Cheng Min gan Jing Chen College of Computer and Data Science Fuzhou UniversityFuzhou350116FujianChina Fujian Key Laboratory of Network Computing and Intelligent Information Processing Fuzhou UniversityFuzhou350116FujianChina Key Laboratory of Intelligent Metro of Universities in Fujian Fuzhou UniversityFuzhou350116FujianChina Engineering Research Center of Big Data Intelligence Ministry of EducationFuzhou UniversityFuzhou350116FujianChina School of Science Jiangnan UniversityWuxi214122JiangsuChina

Separable nonlinear models are widely used in various fields such as time series analysis, system modeling, and machine learning, due to their flexible structures and ability to capture nonlinear behavior of data. However, identifying the parameters of these models is challenging, especially when sparse models with better interpretability are desired by practitioners. Previous theoretical and practical studies have shown that variable projection (VP) is an efficient method for identifying separable nonlinear models, but these are based on \(L_2\) penalty of model parameters, which cannot be directly extended to deal with sparse constraint. Based on the exploration of the structural characteristics of separable models, this paper proposes gradient-based and trust-region-based variable projection algorithms, which mainly solve two key problems: how to eliminate linear parameters under sparse constraint;and how to deal with the coupling relationship between linear and nonlinear parameters in the model. Finally, numerical experiments on synthetic data and real time series data are conducted to verify the effectiveness of the proposed algorithms.

关键词： Variable projection(VP) Non-smooth constraint Separable nonlinear models

Thickness dependence of superconductivity in layered GeP_(5)

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Rare Metals 2024年第3期43卷 1323-1328页

作者： Lin Wu Ke-Meng Yang Wei gan Rui-Chun Xiao Ya-Jie Dai Xi Tang Hong Lin hui Han hui Li Information Materials and Intelligent Sensing Laboratory of Anhui Province Institute of Physical Science and Information TechnologyAnhui UniversityHefei230601China

Understanding the relationship between dimensionality and superconductivity has attracted substantial research *** this work,we report the effective modulation of superconductivity in GeP_(5)through *** superconducting phase transition temperature improves by~10%as the thickness of GeP_(5)decreases from bulk to~96 nm,behaving as a unique negative relationship between the superconducting phase transition temperatureand thickness.

关键词： superconductivity dimensionality

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Acupuncture and moxibustion for irritable bowel syndrome:An umbrella systematic review

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Journal of Integrative Medicine 2024年第1期22卷 22-31页

作者： Yue-ying Ma Zhou Hao Zi-yi Chen Yan-xi Shen hui-rong Liu Huan-gan Wu Chun-hui Bao Shanghai Clinical Research Centre for Acupuncture and Moxibustion Yueyang Hospital of Integrated Chinese and Western MedicineShanghai University of Traditional Chinese MedicineShanghai 200437China Key Laboratory of Acupuncture and Immunological Effects Shanghai University of Traditional Chinese MedicineShanghai 200030China

BackgroundIrritable bowel syndrome(IBS)is a functional bowel disease characterized by abdominal pain or discomfort associated with altered bowel *** clinical studies have demonstrated the effectiveness of acupuncture and moxibustion for *** systematic reviews of acupuncture and moxibustion for IBS have been published in recent years,but their results are not entirely *** evaluate the methodological,reporting,and evidence quality of systematic reviews of acupuncture and moxibustion for *** strategySystematic reviews of acupuncture and moxibustion for IBS published before February 20,2023 were searched in eight databases:PubMed,Embase,Cochrane Library,Web of Science,China National Knowledge Infrastructure,Wanfang Data,VIP Database for Chinese Technical Periodicals,and China Biology *** keywords used for literature search were acupuncture,moxibustion,systematic review,meta-analysis,and irritable bowel *** criteriaSystematic reviews and meta-analyses of randomized controlled trials of acupuncture and moxibustion for IBS were *** extraction and analysisRelevant information was independently extracted by two *** A MeaSurement Tool to Assess systematic Reviews 2(AMSTAR 2),Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA 2020),and Grading of Recommendations Assessment,Development and Evaluation(GRADE)were used to evaluate the methodological quality,reporting quality and evidence quality,*** total of 342 studies were retrieved and 15 systematic reviews were *** results of AMSTAR 2 showed low methodological quality in 2 studies and very low methodological quality in the remaining 13 studies,with main issues being failure to register a protocol,incomplete search strategy,not providing a list of excluded studies,incomplete consideration of the risk of bias in the included studies,and a failure to assess the publication *** results of

关键词： Irritable bowel syndrome Acupuncture Moxibustion Umbrella systematic review Systematic review

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Influence of oxygen-rich hot air composite gas medium on sintering performance and function mechanism

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Journal of Iron and Steel Research International 2024年第5期31卷 1071-1081页

作者： Min gan Hao-xiang Zheng Xiao-hui Fan Zhi-yun Ji Qiang Li Ming Wu Yi-fan Wang Xiao-long Wang Yu-feng Wu Xu-ling Chen Zeng-qing Sun Xiao-xian Huang School of Minerals Processing and Bioengineering Central South UniversityChangsha410083HunanChina Shanxi Taigang Stainless Steel Co. Ltd.Taiyuan030003ShanxiChina

Hot air sintering technology is used to improve the quality and production efficiency of sintered ***,the current thick layer condition highlights the disadvantage of the low oxygen potential of the hot air sintering ***,it is considered to use oxygen enrichment sintering to improve the environment of hot air *** sintering,hot air sintering,and oxygen-rich hot air sintering were compared through sintering cup experiments,and the influence of hot air and oxygen-rich hot air on sintering indexes was *** air reduced the vertical sintering velocity,while improved the yield and tumbler ***-rich hot air sintering contributed to improving the vertical sintering velocity while ensuring the quality of sintered ore,thus comprehensively improving production *** the action of hot air,the highest temperature of the sintering layer increased and the high-temperature holding time was *** oxygen enrichment,the combustion efficiency of fuels in the upper layer of materials was promoted,which optimized heat distribution in the middle and lower layers of materials and increased the content of calcium ferrite in the sintered ore,thus strengthening the sintering process.

关键词： Iron ore sintering Hot air sintering Oxygen enrichment Function mechanism

Synthesis and characterization of iron clusters with an icosahedral [Fe@Fe12]16+ Core

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National Science Review 2024年第4期11卷 123-129页

作者： gan Xu yun-Shu Cui Xue-Lian Jiang Cong-Qiao Xu Jun Li Xu-Dong Chen Jiangsu Collaborative Innovation Center of Biomedical Functional Materials and Jiangsu Key Laboratory of New Power Batteries School of Chemistry and Materials Science Nanjing Normal University Department of Chemistry and Guangdong Provincial Key Laboratory of Catalytic Chemistry Southern University of Science and Technology Department of Chemistry and Engineering Research Center of Advanced Rare-Earth Materials of Ministry of Education Tsinghua University State Key Laboratory of Coordination Chemistry Nanjing University

Iron-metal clusters are crucial in a variety of critical biological and material systems,including metalloenzymes,catalysts,and magnetic storage ***,a synthetic high-nuclear iron cluster has been absent due to the extreme difficulty in stabilizing species with direct iron-iron *** this work,we have synthesized,crystallized,and characterized a（Tp*）4W4S12(Fe@Fe12) cluster(Tp*=tris（3,5-dimethyl-1-pyrazolyl）borate（1-）),which features a rare trideca-nuclear,icosahedral[Fe@Fe12] cluster core with direct multicenter iron-iron bonding between the interstitial iron（Fei） and peripheral irons（Fep）,as well as Fep…Fepferromagnetic *** chemistry studies reveal that the stability of the cluster arises from the 18-electron shell-closing of the [Fe@Fe12]16+core,assisted by its bonding interactions with the peripheral tridentate [（Tp*）WS3]4-ligands which possess both S→Fe donation and spin-polarized Fe-Wσ *** ground-state electron spin is theoretically predicted to be S=32/2 for the *** existence of low oxidation-state（OS～+1.23） iron in this compound may find interesting applications in magnetic storage,spintronics,redox chemistry,and cluster catalysis.

关键词： Fe13 cluster iron-sulfur cluster low-valence iron iron−iron bond high spin complex

Atomically dispersed materials:Ideal catalysts in atomic era

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Nano Research 2024年第1期17卷 18-38页

作者： Tao gan Dingsheng Wang Department of Chemistry Tsinghua UniversityBeijing 100084China

Catalysts can accelerate the chemical reaction rate and effectively promote the molecules transformation,which is of great significance in the research of chemical industry and material *** extreme utilization of reactive sites has led to the emergence and development of atomically dispersed materials(ADMs).The highly active coordination unsaturated metal sites and fully utilized metal atoms make ADMs show great potential in catalytic *** adjustment of coordination environment and electronic structure provides more possibilities for constructing reactive centers with different *** review summarized the application and research progress of ADMs in different *** design strategy and structure–activity relationship of ADMs for specific reactions were summarized and ***,we also provided advices for the challenges and opportunities faced by ADMs in catalytic reactions.

关键词： atomically dispersed materials catalysis organic synthesis battery sensor enzyme

Tandem asymmetric dearomatized functionalization reaction of phenols with Evans-ynamides enabled by divergent electrophiles

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Science China Chemistry 2024年

作者： Ying-Qi Zhang gan-Lu Qian yun Liu Jia-hui Li Xin Hong Zhou Xu Bo Zhou Long-Wu Ye State Key Laboratory of Physical Chemistry of Solid Surfaces Key Laboratory of Chemical Biology of Fujian Province and College of Chemistry and Chemical Engineering Xiamen University Center of Chemistry for Frontier Technologies Department of Chemistry State Key Laboratory of Clean Energy Utilization Zhejiang University Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy School of Pharmacy Xuzhou Medical University State Key Laboratory of Elemento-Organic Chemistry Nankai University State Key Laboratory of Organometallic Chemistry Chinese Academy of Sciences

Herein, we disclose a highly regio-/chemoselective tandem asymmetric dearomatized halofunctionalization reaction of phenoltethered ynamides with diverse electrophilic halogenation sources in a catalyst-free manner for the practical and rapid assembly of a series of halogenated spirocyclic enones. Besides, the related dearomatized selenation and protonation are also achieved,affording the corresponding selenated and protonated spirocycles in high efficiency. Moreover, the enantioselectivities of these products can be perfectly induced by Evans auxiliaries (99%ees). Significantly, this protocol not only represents the first tandem asymmetric halofunctionalization reaction of phenol derivatives, but also constitutes the first asymmetric halogenation/selenation of ynamides. Theoretical calculations indicate a remote induction model of Evans chiral auxiliary-attached keteniminium.

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