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Stereoselective Synthesis of 2-Deoxy-α-N-Glycosides from Glycals with 1,4,2-Dioxazol-5-ones

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Chinese Journal of Chemistry 2024年第18期42卷 2147-2152页

作者： Zhenpeng Shen Guoyin Yin Yangyang Li The institute for Advanced studies Wuhan UniversityWuhanHubei 430072China

The synthesis of N-glycosides has received significant attention due to their crucial role in carbohydrate *** considerable advancements developed in the construction of N-glycosides,methods for the stereoselective construction of 2-deoxy-α-N-glycosides are still ***,we disclosed a nickel-catalyzed hydroamination of glycals under mild *** transformation could allow for the stereoselective synthesis of an array of 2-deoxy-α-N-glycosides with excellentα-***-catalyzed glycosylation reactions,particularly those involving anomeric C(sp")-metal bond formation,have proven to be an effective and stereoselective strategy for producing various ***,with highlight of the application of this reaction,y-sugar amino acidderivatives weresynthesized.

关键词： 2-Deoxy-α-N-glycosides Nickel catalysis Stereoselectivity Glycals Hydroamination Amides Glycosylation Alkenes ComprehensiveSummary

Nickel-Catalyzed Stereoselective Migratory Carboboration of 1,4-Cyclohexadiene

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Chinese Journal of Chemistry 2024年第4期42卷 356-362页

作者： Yaoyu Ren Lujin Wang Chao Ding Yangyang Li Guoyin Yin The institute for Advanced studies Wuhan UniversityWuhanHubei430072 China

Multi-substituted cyclohexanes play a crucial role as scaffolds in bioactive *** significant progress has been made in synthesizing substituted cyclohexanes,methods for the stereoselective assembly of 1,3-disubstituted cyclohexanes remain *** study presents a novel approach involving nickel catalysis to achieve stereoselective carboboration of 1,*** innovative process allows for the simultaneous introduction of a boron group and an aryl or an alkyl fragment into the 1,4-cyclohexadiene framework under mild conditions,with exclusive regioselectivity and excellent cis *** resulting products feature a double carbon bond and the incorporation of the boron group,offering significant potential for subsequent transformations and downstream applications.

关键词： 1,4-Cyclohexadiene Carboboration Nickel Chain-walking Stereoselectivity Difunctionalization

The recombinant jasmonate ZIM-domain(JAZ)protein functions as a novel insecticidal protein against Lepidopteran pests

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Science china(Life Sciences) 2024年第8期67卷 1777-1778页

作者： Yuxian Zhu institute for Advanced studies Wuhan UniversityWuhan 430072China

Lepidopterans,including butterflies and moths,make up one-tenth of all described agricultural pests on Earth,and many of them,such as fall armyworm,cotton bollworm,corn borer and rice leaf folder,are major agricultura... 详细信息

关键词： pests agricultural cotton

BCCLR:A Skeleton-Based Action Recognition with Graph Convolutional Network Combining Behavior Dependence and Context Clues

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Computers, Materials & Continua 2024年第3期78卷 4489-4507页

作者： Yunhe Wang Yuxin Xia Shuai Liu College of Information Science and Engineering Institute of Interdisciplinary StudiesHunan Normal UniversityChangsha410081China School of Educational Sciences Institute of Interdisciplinary StudiesHunan Normal UniversityChangsha410081China

In recent years,skeleton-based action recognition has made great achievements in Computer Vision.A graph convolutional network(GCN)is effective for action recognition,modelling the human skeleton as a spatio-temporal *** GCNs define the graph topology by physical relations of the human ***,this predefined graph ignores the spatial relationship between non-adjacent joint pairs in special actions and the behavior dependence between joint pairs,resulting in a low recognition rate for specific actions with implicit correlation between joint *** addition,existing methods ignore the trend correlation between adjacent frames within an action and context clues,leading to erroneous action recognition with similar ***,this study proposes a learnable GCN based on behavior dependence,which considers implicit joint correlation by constructing a dynamic learnable graph with extraction of specific behavior dependence of joint *** using the weight relationship between the joint pairs,an adaptive model is *** also designs a self-attention module to obtain their inter-frame topological relationship for exploring the context of *** the shared topology and the multi-head self-attention map,the module obtains the context-based clue topology to update the dynamic graph convolution,achieving accurate recognition of different actions with similar *** experiments on public datasets demonstrate that the proposed method achieves better results and realizes higher quality representation of actions under various evaluation protocols compared to state-of-the-art methods.

关键词： Action recognition deep learning GCN behavior dependence context clue self-attention

Toxicity of the disinfectant benzalkonium chloride(C_(14))towards cyanobacterium Microcystis results from its impact on the photosynthetic apparatus and cell metabolism

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Journal of Environmental Sciences 2024年第1期135卷 198-209页

作者： Yunlu Jia Yi Huang Jin Ma Shangwei Zhang Jin Liu Tianli Li Lirong Song institute of Hydrobiology Chinese Academy of SciencesWuhan 430072China School of Environmental studies China University of GeosciencesWuhan 430074China Advanced Interdisciplinary institute of Environment and Ecology Beijing Normal UniversityZhuhai 519087China

Quaternary ammonium compounds(QACs)are commonly used in a variety of consumer and commercial products,typically as a component of *** the COVID-19 pandemic,QACs became one of the primary agents utilized to inactivate the SARS CoV-2 virus on ***,the ecotoxicological effects of QACs upon aquatic organisms have not been fully *** this study,we examined the effects of a widely used QAC(benzalkonium chloride-C_(14),BAC-14)on two toxigenic Microcystis strains and one non-toxigenic freshwater Microcystis strain and carried out an analysis focused on primary,adaptive and compensatory stress responses at apical(growth and photosynthesis)and metabolic *** analysis revealed that the two toxic Microcystis strains were more tolerant than the non-toxic strain,with 96 hr-EC_(50)values of 0.70,0.76,and 0.38 mg/L BAC-14 for toxigenic *** FACHB-905,toxigenic *** FACHB-469,and non-toxigenic *** FACHB-908,*** photosynthetic activities of the Microcystis,assessed via F_(v)/F_(m) values,were significantly suppressed under 0.4 mg/L ***,this analysis revealed that BAC-14 altered 14,12,and 8 metabolic pathways in *** FACHB-905,*** FACHB-469,and *** FACHB-908,*** is noteworthy that BAC-14 enhanced the level of extracellular microcystin production in the toxigenic Microcystis strains,although cell growth was not significantly ***,these data show that BAC-14 disrupted the physiological and metabolic status of Microcystis cells and stimulated the production and release of microcystin,which could result in damage to aquatic systems.

关键词： Disinfectants Quaternary ammonium compounds Microcystis Cyanotoxin Metabolomics Chlorophyll fluorescence

General radical difluoromethylation using difluoroacetic anhydride via photoredox catalysis

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Science china Chemistry 2024年第8期67卷 2637-2646页

作者： Meng He Yankai Yang Heng Zhang Zhipeng Guan Zhi-Bing Dong Hong Yi Aiwen Lei School of Chemistry and Environmental Engineering Wuhan Institute of TechnologyWuhan 430205China College of Chemistry and Molecular Sciences and institute for Advanced studies(IAS) Wuhan UniversityWuhan 430072China

CF_(2)H-containing molecules play pivotal roles in diverse fields from medicinal chemistry to materials science. However, the application of existing CF_(2)H reagents as a source of CF_(2)H radical is limited by their reactivity and preparation. Herein, we develop a simple and general visible-light-catalyzed radical difluoromethylation reaction of alkenes, dienes, and heteroaromatics using commercially available, easy-to-handle, and low-cost difluoroacetic anhydride as the CF_(2)H reagent. This scalable protocol enables the convenient synthesis of a range of CF_(2)H-containing compounds under mild conditions, exhibiting a broad substrate scope and functional group tolerance. Potential applications are further demonstrated by gram-scale synthesis, sunlight experiments, derivatization experiments as well as the synthesis of bioactive molecules.

关键词： radical difluoromethylation alkenes/dienes/heteroaromatics difluoroacetic anhydride photoredox

Visible-light-activated aziridination reaction enables simultaneous resolving of C=C bond location and the sn-position isomers in lipids

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Chinese Chemical Letters 2024年第4期35卷 481-485页

作者： Qiongqiong Wan Yanan Xiao Guifang Feng Xin Dong Wenjing Nie Ming Gao Qingtao Meng Suming Chen The institute for Advanced studies Renmin Hospital of Wuhan UniversityWuhan UniversityWuhan 430072China

There is a close relationship between the biological functions of lipids and their structures, and various isomers greatly increases the complexity of lipid structures. The C=C bond location and sn-position are two of the essential attributes that determine the structures of unsaturated lipids. However, simultaneous identification of both attributes remains challenging. Here, we develop a visible-light-activated aziridination reaction system, which enables the dual-resolving of the C=C bond location and sn-position isomerism of in lipids when combines with liquid chromatography-mass spectrometry(LC-MS). Based on the derivatization of C=C bonds with Ph I=NTs, their location in lipids could be easily identified by tandem MS. Especially, the sn-position isomers of unsaturated phosphatidylcholine(PC) can be separated and quantified by LC-MS after the derivatization. By using the proposed method, the significant changes of the sn-position isomers ratios of PC in mouse brain ischemia were revealed. This study offers a powerful tool for deep lipid structural biology.

关键词： Aziridination Lipid isomers C=C bond location sn-Position Mass spectrometry

Restimate:Recovery Estimation Tool for Resilience Planning

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Journal of Safety Science and Resilience 2024年第1期5卷 47-63页

作者： Scott Miles Megan Ly Nick Terry Youngjun Choe Department of Human Centered Design&Engineering Campus Box 352315University of WashingtonSeattleWA 98195United States of America Department of Industrial&Systems Engineering Box 352650University of WashingtonSeattleWA 98195United States of America

The *** institute of Standards and Technology(NIST)published the Community Resilience Planning Guide in *** NIST Guide advocates for a participatory process for developing a performance measurement framework for the jurisdiction’s resilience against a scenario *** framework centers around tables of expected and desired recovery times for selected community assets,such as electricity,water,and natural gas *** NIST Guide does not provide a method for estimating the expected recovery ***,building high-fidelity computer models for such estimations requires substantial resources that even larger ju-risdictions cannot *** most promising approach to recovery time estimation is to systematically use data elicited from people to tap into the wisdom of the(knowledgeable)*** paper describes a novel research-through-design project to enable the computer-supported elicitation of recovery time series *** work is the first in the literature to examine people’s ability to estimate recovery curves and how design in-fluences such *** main contribution to resilience planning is three-fold:development of a new elicitation tool called Restimate,understanding its potential user base,and providing insights into how it can facilitate resilience *** is the first tool to enable evidence-based expert elicitation in any community with limited resources for resilience *** resilience planning,those who facilitate high-stakes planning activities under large uncertainties(e.g.,mission-critical system design and planning)will benefit from a similar research-through-design process.

关键词： expert elicitation disaster natural hazard infrastructure community resilience restoration user-centered design computer-supported cooperative work

Text Reasoning Chain Extraction for Multi-Hop Question Answering

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Tsinghua Science and Technology 2024年第4期29卷 959-970页

作者： Pengming Wang Zijiang Zhu Qing Chen Weihuang Dai School of Data Science and Artificial Intelligence Wenzhou University of TechnologyWenzhou 325035China School of Computer Science and also with Institute of Intelligent Information ProcessingSouth China Business CollegeGuangdong University of Foreign StudiesGuangzhou 510545China School of Psychology Jiangxi Normal UniversityNanchang 330022China also with School of Science East China Jiaotong UniversityNanchang 330013China institute of Intelligent Information Processing South China Business CollegeGuangdong University of Foreign StudiesGuangzhou 510545China

With the advent of the information age, it will be more troublesome to search for a lot of relevant knowledge to find the information you need. Text reasoning is a very basic and important part of multi-hop question and answer tasks. This paper aims to study the integrity, uniformity, and speed of computational intelligence inference data capabilities. That is why multi-hop reasoning came into being, but it is still in its infancy, that is, it is far from enough to conduct multi-hop question and answer questions, such as search breadth, process complexity, response speed, comprehensiveness of information, etc. This paper makes a text comparison between traditional information retrieval and computational intelligence through corpus relevancy and other computing methods. The study finds that in the face of multi-hop question and answer reasoning, the reasoning data that traditional retrieval methods lagged behind in intelligence are about 35% worse. It shows that computational intelligence would be more complete, unified, and faster than traditional retrieval methods. This paper also introduces the relevant points of text reasoning and describes the process of the multi-hop question answering system, as well as the subsequent discussions and expectations.

关键词： intelligent computing multi-hop quiz text reasoning document retrieval text complex network