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Chinese Journal of Structural Chemistry 2008年第11期27卷 1389-1392页

作者：陈小保李克石德清 Key Laboratory of Pesticide and Chemical biology of Ministry of education of China College of ChemistryCentral China Normal University

The crystal structure of the title compound （C12H10ClN7OS, Mr= 335.78） has been determined by single-crystal X-ray diffraction. The crystal is of triclinic, space group Pi with a = 8.4093（11）, b = 9.4430（12）, c = 11.1454（14） A, α = 95.508（2）, β = 111.366（2）, γ = 115.259（2）°, V = 711.42（16） A3, Z = 2, Dc = 1.568 g/cm3, F（000） = 344, μ（MoKα） = 0.428 mm-1, the final R = 0.0476 and wR = 0.1243 for 2353 observed reflections （I 〉 2o（/））. The dihedral angles between the pyridine and triazole, thiazole and triazole, and pyridine and thiazole rings are 69.2（1）, 9.2（1） and 72.7（1）°, respectively. Intramolecular C（8）--H（8B）...O（1） and N（5）-H（5A）..-N（4） as well as intermolecular C（5）-H（5）...S（1）, C（3）-H（3）.,.N（6） and N（5）-H（5A）...N（1） hydrogen bonds together with weak C-H...Ir hydrogen-bonding and π-π stacking interactions contribute to the stability of the structure. There is also evidence for significant electron delocalization in the triazolyl system.

关键词： crystal structure synthesis carboxamide herbicide

Interaction of Ethylene-N,N'-dianthranilate to Ni(Ⅱ):Binding Properties and Coordination Mode Studies

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Chinese Journal of Structural Chemistry 2013年第12期32卷 1787-1792页

作者： FENG Jiao WANG Jing-Lin LIU Bin YANG Bin-Sheng Key Laboratory of Chemical biology and Molecular Engineering of Ministry of education Institute of Molecular ScienceShanxi University

The binding properties of ethylene-N,N＇-dianthranilate （EDA） and Ni（II） were studied by difference UV-Vis in 0.05 M Tris-HCl buffer （pH 7.4）. The stoichiometric ratio of EDA to nickel （1：1） was confirmed and the conditional binding constant （IogKNi-EDA = 12.33 ± 0.06） was obtained. In addition, an interesting tetranuclear complex [Nin（EDA）4]·2CH3CH2OH-9H2O was obtained unexpectedly in alcohol-water solution and characterized by X-ray crystallography and electrospray ionization mass spectra （ESI-MS）. It is found that EDA acts as a pentadentate ligand and performs a chelating-bridging coordination mode.

关键词： ethylene-N,N'-dianthranilate Ni(Ⅱ) spectrum crystal structure

Synthesis of Ras proteins and their application in biofunctional studies

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Chinese Chemical Letters 2018年第7期29卷 1043-1050页

作者： Jun Hu Pengcheng Zhu Yanmei Li Yongxiang Chen Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical biology(Ministry of education) Department of ChemistryTsinghua University

Approximately 30% of human cancers are associated with RAS mutation. Ras proteins on the plasma membrane regulate a plenty of important cellular processes. The post-translational modifications(PTMs)of Ras proteins like lipidation and methylation are crucial for their correct cellular localization and biological function. Hence, obtaining Ras proteins with different kinds of modifications is the necessary prerequisite to investigate their biological properties at molecular level. In this review, we mainly summarize the developed strategies including chemical total synthesis, biosynthesis and semi-synthesis for producing Ras proteins with modifications and their application in biological studies.

关键词： Ras Lipopeptides Semi-synthesis Multi-PTMs Biophysical function

Marine bacterium strain screening and pyrethroid insecticide-degrading efficiency analysis

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Chinese Journal of Oceanology and Limnology 2014年第5期32卷 1029-1035页

作者：孙爱丽刘菁华史西志李德祥陈炯唐道军 Key Laboratory of Applied Technology of Marine biology Ministry of Education School of Marine Sciences Ningbo University

A pyrethroid insecticide-degrading bacterium, strain HS-24, was isolated from an offshore seawater environment. The strain, which can degrade cypermethrin （CYP） and deltamethrin （DEL）, was identified as Methylophaga sp. The optimal culture and degradation conditions for CYP and DEL by strain HS-24 is pH 7 at 28℃. Under optimum culture conditions, strain HS-24 exhibited a broad degradation concentration range of 100, 200, 400, 600, and 800 mg/L for CYP and DEL. The metabolic intermediates were analyzed by NMR, which provided strong evidence that CYP and DEL removal occurred mainly because of a biological process. The toxicity of the degradation products of strain HS-24 was studied simultaneously by measuring the light output of the luminescence bacterium. This demonstrated that the biodegradation ability of strain HS-24 significantly decreased the toxicity of CYP- and DEL-contaminated aquaculture seawater. Finally, the findings of this paper indicate that strain HS-24 is thus revealed as a biological agent for the remediation of marine aquatic environments.

关键词： pyrethroid insecticide-degrading bacteria seawater environment Methylophaga sp. HS-24

Citrus β-carotene hydroxylase 2 (BCH2) participates in xanthophyll synthesis by catalyzing the hydroxylation of β-carotene and compensates for BCH1 in citrus carotenoid metabolism

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Horticulture Research 2023年第3期10卷 45-56页

作者： Yingzi Zhang Jiajing Jin Shenchao Zhu Quan Sun Yin Zhang Zongzhou Xie Junli Ye Xiuxin Deng Key Laboratory of Horticultural Plant biology(Ministry of education) Huazhong Agricultural UniversityWuhan430070China

Abstract As an essential horticultural crop,Citrus has carotenoid diversity,which affects its aesthetic and nutritional values.β,β-Xanthophylls are the primary carotenoids accumulated in citrus fruits,and non-heme di-iron carotene hydroxylase(BCH)enzymes are mainly responsible forβ,β-xanthophyll *** studies have focused on the hydroxylation of BCH1,but the role of its paralogous gene in citrus,BCH2,remains largely *** this study,we revealed theβ-hydroxylation activity of citrus BCH2(CsBCH2)for the first time through the functional complementation assay using Escherichia coli,although CsBCH2 exhibited a lower activity in hydroxylatingβ-carotene intoβ-cryptoxanthin than citrus BCH1(CsBCH1).Our results showed that overexpression of CsBCH2 in citrus callus increased xanthophyll proportion and plastoglobule size with feedback regulation of carotenogenic gene *** study revealed the distinct expression patterns and functional characteristics of two paralogous genes,CsBCH1 and CsBCH2,and illustrated the backup compensatory role of CsBCH2 for CsBCH1 in citrus xanthophyll *** independent function of CsBCH2 and its cooperative function with CsBCH1 inβ-cryptoxanthin biosynthesis suggested the potential of CsBCH2 to be employed for expanding the synthetic biology toolkit in carotenoid engineering。

关键词： citrus Citrus metabolism

Study of the interaction of unaggregated and aggregated amyloid β protein (10-21) with outward potassium channel

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Science China Chemistry 2007年第5期50卷 683-691页

作者： ZHANG ChaoFeng FAN Li YANG Pin Key Laboratory of Chemical biology and Molecular Engineering of Ministry of education Institute of Molecular Science Shanxi University Taiyuan 030006 China Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education Institute of Molecular Science Shanxi University Taiyuan 030006 China Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education Institute of Molecular Science Shanxi University Taiyuan 030006 China

Metal ion-induced aggregation of A beta into insoluble plaques is a centralfactor in Alzheimer's ***^(2+) is the only physiologically available transition metal ionresponsible for aggregating A beta at pH *** make it clear that the neurotoxicity ofZn^(2+)-induced aggregation of A beta on neurons is the key to understand A beta mechanism of *** this paper,we choose A/?(10-21) as the model fragment to research hippocampal CA1pyramidal *** the first time,we adopt the combination of spectral analysis with patch-clamptechnique for the preliminary study of the mutual relations of Zn^(2+),A beta and ion channel fromthe cell *** following expounds upon the effects and mode of action of two forms (unaggregatedand aggregated) of A beta(10-21) on hippocampus outward potassium channel three processes(activation,inactivation and reactivation).It also shows the molecular mechanics of AD from thechannel *** results are significant for the further study of A beta nosogenesis and thedevelopment of new types of target drugs for the treatment of AD.

关键词： potassium channel amyloid beta protein (10-21) Zn^(2+) alzheimer's disease

Copy Move Forgery Detection Using Novel Quadsort Moth Flame Light Gradient Boosting Machine

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Computer Systems Science & Engineering 2023年第5期45卷 1577-1593页

作者： R.Dhanya R.Kalaiselvi Department of Computer Applications Noorul Islam Centre for Higher EducationNagercoil629180India Department of Computer Science Engineering Noorul Islam Centre for Higher EducationNagercoil629180India

A severe problem in modern information systems is Digital media tampering along with fake *** though there is an enhancement in image development,image forgery,either by the photographer or via image manipulations,is also done in *** researches have been concentrated on how to identify such manipulated media or information manually along with automatically;thus conquering the complicated forgery methodologies with effortlessly obtainable technologically enhanced ***,high complexity affects the developed ***,it is complicated to resolve the issue of the speed-accuracy *** tackling these challenges,this article put forward a quick and effective Copy-Move Forgery Detection(CMFD)system utilizing a novel Quad-sort Moth Flame(QMF)Light Gradient Boosting Machine(QMF-Light GBM).Utilizing Borel Transform(BT)-based Wiener Filter(BWF)and resizing,the input images are initially pre-processed by eliminating the noise in the proposed *** that,by utilizing the Orientation Preserving Simple Linear Iterative Clustering(OPSLIC),the pre-processed images,partitioned into a number of grids,are ***,as of the segmented images,the significant features are extracted along with the feature’s distance is calculated and matched with the input ***,utilizing the Union Topological Measure of Pattern Diversity(UTMOPD)method,the false positive matches that took place throughout the matching process are *** that,utilizing the QMF-Light GBM visualization,the visualization of forged in conjunction with non-forged images is *** extensive experiments revealed that concerning detection accuracy,the proposed system could be extremely precise when contrasted to some top-notch approaches.

关键词： Borel transform based wiener filter(BWF) orientation preserving simple linear iterative clustering(OPSLIC) keypoint features block features outlier detection

Evolutionary Algorithm Based Feature Subset Selection for Students Academic Performance Analysis

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Intelligent Automation & Soft Computing 2023年第6期36卷 3621-3636页

作者： Ierin Babu R.MathuSoothana S.Kumar Department of Computer Science and Engineering Noorul Islam Centre for Higher EducationKanyakumari629180India Department of Information Technology Noorul Islam Centre for Higher EducationKanyakumari629180India

educational Data Mining(EDM)is an emergent discipline that concen-trates on the design of self-learning and adaptive *** education institutions have started to utilize analytical tools to improve students’grades and *** of students’performance is a difficult process owing to the massive quantity of educational ***,Artificial Intelligence(AI)techniques can be used for educational data mining in a big data *** the same time,in EDM,the feature selection process becomes necessary in creation of feature *** the feature selection performance affects the predictive performance of any model,it is important to elaborately investigate the outcome of students’performance model related to the feature selection *** this motivation,this paper presents a new Metaheuristic Optimiza-tion-based Feature Subset Selection with an Optimal Deep Learning model(MOFSS-ODL)for predicting students’*** addition,the proposed model uses an isolation forest-based outlier detection approach to eliminate the existence of ***,the Chaotic Monarch Butterfly Optimization Algo-rithm(CBOA)is used for the selection of highly related features with low com-plexity and high ***,a sailfish optimizer with stacked sparse autoencoder(SFO-SSAE)approach is utilized for the classification of educational *** MOFSS-ODL model is tested against a benchmark student’s perfor-mance data set from the UCI repository.A wide-ranging simulation analysis por-trayed the improved predictive performance of the MOFSS-ODL technique over recent approaches in terms of different *** to other methods,experimental results prove that the proposed(MOFSS-ODL)classification model does a great job of predicting students’academic progress,with an accuracy of 96.49%.

关键词： Students’performance analysis educational data mining feature selection deep learning metaheuristics outlier detection

Stimuli-responsive organic chromic materials with near-infrared emission

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Chinese Chemical Letters 2018年第10期29卷 1429-1435页

作者： Weijie Chen Yingle Pan Jianhua Chen Fengying Ye Sheng Hua Liu Jun Yin Key Laboratory of Pesticide and Chemical biology Ministry of EducationCollege of ChemistryCentral China Normal University

Organic chromic materials that respond to external stimuli, especially in the solid state, have sparked extensive interest owing to their potential use as smart materials. In particular, the availability of chromic materials, which emit fluorescence or phosphorescence in the deep penetrating, near-infrared（NIR）region, has led to great improvements in imaging. Various methods that were commonly applied to construct chromic materials, have been reformed to develop the novel type of compounds, and some have received rewards with excellent fingdings. Relevant research achievements of practical applications have showed their potential with the changes that locate in the NIR region, while further in-depth explorations about the inherent chromic chromism are underway. In this review, several representative studies, which have led the development of responsive organic chromic materials with near-infrared emission, will be discussed.

关键词： Stimuli-response Near-infrared emission Fluorescent dyes Chromic materials Mechanochromism

Two Lycopene β-Cyclases Genes from Sweet Orange (Citrus sinensis L. Osbeck) Encode Enzymes With Different Functional Efficiency During the Conversion of Lycopene-to-Provitamin A

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Journal of Integrative Agriculture 2013年第10期12卷 1731-1747页

作者： ZHANG Jian-cheng ZHOU Wen-jing XU Qiang TAO Neng-guo YE Jun-li GUO Fei XU Juan DENG Xiu-xin Key Laboratory of Horticultural Plant biology Ministry of Education/College of Horticulture and ForestryHuazhong Agricultural University

Citrus fruits are rich in *** the carotenoid biosynthetic pathway,lycopene β-cyclase（LCYb,EC：1.14.-.-） is a key regulatory enzyme in the catalysis of lycopene to β-carotene,an important dietary precursor of vitamin A for human *** closely related lycopene β-cyclase cDNAs,designated CsLCYb1 and CsLCYb2,were isolated from the pulp of orange fruits（Citrus sinensis）.The expression level of CsLCYb genes is lower in the flavedo and juice sacs of a lycopeneaccumulating genotype Cara Cara than that in common genotype Washington,and this might be correlated with lycopene accumulation in Cara Cara *** CsLCYb1 efficiently converted lycopene into the bicyclic β-carotene in an Escherichia coli expression system,but the CsLCYb2 exhibited a lower enzyme activity and converted lycopene into the β-carotene and the monocyclic γ-*** tomato transformation studies,expression of CsLCYb1 under the control of the cauliflower mosaic virus（CaMV） 35S constitutive promoter resulted in a virtually complete conversion of lycopene into β-carotene,and the ripe fruits displayed a bright orange ***,the CsLCYb2 transgenic tomato plants did not show an altered fruit colour during development and *** fruits of the CsLCYb1 transgenic plants,most of the lycopene was converted into β-carotene with provitamin A levels reaching about 700 μg ***,most transgenic tomatoes showed a reduction in total carotenoid accumulation,and this is consistent with the decrease in expression of endogenous carotenogenic genes in transgenic ***,these results suggested that the cloned CsLCYb1 and CsLCYb2 genes encoded two functional lycopene β-cyclases with different catalytic efficiency,and they may have potential for metabolite engineering toward altering pigmentation and enhancing nutritional value of food crops.

关键词： carotenoids biosynthesis citrus fruit gene expression lycopene lycopene β-cyclase β-Carotene transgenic tomato fruit