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Rational surface charge engineering of haloalkane dehalogenase for boosting the enzymatic performance in organic solvent solutions

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Chinese Journal of Chemical Engineering 2024年第1期65卷 276-285页

作者： Yin Wu yan sun Department of Biochemical Engineering School of Chemical Engineering and Technology and Key Laboratory of Systems Bioengineering and Frontiers Science Center for Synthetic Biology(Ministry of Education)Tianjin UniversityTianjin 300350China

Biocatalysis in organic solvents(OSs)has numerous important applications,but native enzymes in OSs often exhibit limited catalytic ***,we proposed a computation-aided surface charge engineering strategy to improve the catalytic performance of haloalkane dehalogenase DhaA in OSs based on the energetic analysis of substrate binding to the DhaA *** variants with enhanced OS resistance were obtained by replacing negative charged residues on the surface with positive charged residue(Arg).Particularly,a four-substitution variant E16R/E93R/E121R/E257R exhibited the best catalytic performance(five-fold improvement in OS resistance and seven-fold half-life increase in 40%(vol)dimethylsulfoxide).As a result,the overall catalytic performance of the variant could be at least 26 times higher than the wild-type *** spectroscopy and molecular dynamics simulation studies revealed that the residue substitution mainly enhanced OS resistance from four aspects:(a)improved the overall structural stability,(b)increased the hydrophobicity of the local microenvironment around the catalytic triad,(c)enriched the hydrophobic substrate around the enzyme molecule,and(d)lowered the contact frequency between OS molecules and the catalytic *** findings validate that computationaided surface charge engineering is an effective and ingenious rational strategy for tailoring enzyme performance in OSs.

关键词： Surface charge engineering Organic solvent resistance Molecular dynamics simulation Haloalkane dehalogenase

Towards Data-Driving Multi-View Evaluation Framework for Scratch

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Tsinghua Science and Technology 2024年第2期29卷 517-528页

作者： Xiaolin Chai yan sun yan Gao Department of Computer Science Beijing University of Posts and TelecommunicationBeijing 100876China Intellectual Property Institute Shandong Polytechnic CollegeJining 272067China

As one of the most popular visual programming languages,Scratch has a lot of evaluation around *** evaluation can help programmers understand their projects *** the same time,it can also provide a reference for them to browse other projects in the online *** of the existing evaluations on Scratch are carried from three perspectives:Computational Thinking(CT)ability,visual presentation aesthetics,and code *** them,the assessment of CT and code quality is mainly carried out from the program script,while the evaluation of visual aesthetics is analyzed from the perspective of image sequences generated by project *** single-view evaluation focuses on the performance of a program in a certain aspect and is *** this paper,we propose a multi-view evaluation framework to integrate various evaluations using different *** quantitatively analyze the assessment of different views driven by *** with overall evaluations that represent human opinions,we analyze their differences and *** experiments,we determine the weights of different integration policies,the proposed multi-view evaluation method can generate evaluation results similar to human opinions.

关键词： Scratch Computational Thinking(CT) visual aesthetic static analysis integration policy machine learning

The BTB/TAZ domain-containing protein CmBT1-mediated CmANR1 ubiquitination negatively regulates root development in chrysanthemum

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Journal of Integrative Plant Biology 2024年第2期66卷 285-299页

作者： Lian-Da Du Zhang-Ji Guan yan-Hong Liu Hui-Dong Zhu Quan sun Da-gang Hu Cui-Hui sun Shandong Collaborative Innovation Center of Fruit&Vegetable Quality and Efficient Production College of Horticulture Science and EngineeringShandong Agricultural UniversityTaian 271018China

Roots are fundamental for plants to adapt to variable environmental *** development of a robust root system is orchestrated by numerous genetic determinants and,among them,the MADS-box gene ANR1 has garnered substantial *** research has demonstrated that,in chrysanthemum,CmANR1positively regulates root system ***,the upstream regulators involved in the CmANR1-mediated regulation of root development remain *** this study,we successfully identified bric-a-brac,tramtrack and broad(BTB)and transcription adapter putative zinc finger(TAZ)domain protein CmBT1 as the interacting partner of CmANR1 through a yeasttwo-hybrid(Y2H)screening ***,we validated this physical interaction through bimolecular fluorescence complementation and pull-down *** assays revealed that CmBT1 exerted a negative influence on root development in *** both in vitro and in vivo assays,it was evident that CmBT1mediated the ubiquitination of CmANR1 through the ubiquitin/26S proteasome *** ubiquitination subsequently led to the degradation of the CmANR1 protein and a reduction in the transcription of CmANR1-targeted gene CmPIN2,which was crucial for root development in *** analysis suggested that CmBT1 modulated root development,at least in part,by regulating the level of CmANR1 ***,these findings shed new light on the regulatory role of CmBT1 in degrading CmANR1 through ubiquitination,thereby repressing the expression of its targeted gene and inhibiting root development in chrysanthemum.

关键词： chrysanthemum MADS-box transcription factor root development

Particles attrition of binary mixtures in the coal-fueled chemical looping system based on fluidized bed

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Particuology 2024年第3期86卷 281-290页

作者： Heyu Li Zhe sun yan Cao Guangzhou Institute of Energy Conversion Chinese Academy of SciencesGuangzhou 510640China University of Chinese Academy of Sciences Bejing 100049China CAS Key Laboratory of Renewable Energy Guangzhou 510640China Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development Guangzhou 510640China College of Chemistry and Chemical Engineering Anhui UniversityHefei230601China

In this work,a reactive air jet attrition device with auto-recording and collection of elutriated fines was *** established insights into the physiochemical interaction and further correlated attrition behaviors between char and oxygen carriers under various operation *** attrition rate increased by over 110% upon the introduced CO_(2),which brought in the significant effect of thermo-chemical stress,similarly in effects of the increased char addition ratio and the decreased sizes of char or hematite in different *** the char-hematite co-attrition process,the elutriated carbon loss of char with poor mechanical strength was found to be over 10%,while the reactive iron loss of hematite was found to be 6.3%,and was enriched in elutriated *** reaction-derived thermochemical stress and the collision-derived mechanical stress jointly controls the particle attrition during the cyclic transformation of oxygen carrier particles in coal-fueled chemical looping fluidization,especially sig-nificant in its reduction stage.

关键词： Attrition Binary species Chemical looping Oxygen carrier CO_(2)capture

Iron-nickel alloy particles with N-doped carbon “armor” as a highly selective and long-lasting catalyst for the synthesis of Nbenzylaniline molecules

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Nano Research 2024年第4期17卷 2308-2319页

作者： gang Wang Longchao sun Wanyi Liu Haijuan Zhan Shuxian Bi College of Chemistry and Chemical Engineering Ningxia UniversityYinchuan 750021China

A scalable strategy for the convenient and rapid preparation of nitrogen-doped carbon-coated iron-based alloy catalysts was *** controlling the type and amount of metal salts in the precursor,various types of nitrogen-doped carbon-coated alloy catalysts can be prepared in a targeted ***_(2)Ni2@CN materials with small particle sizes and relatively homogeneous basic sites showed promising results in the N-alkylation reaction of benzyl alcohol with aniline(optimum yield:99%).It is worth noting that the catalyst can also be magnetically separated and recovered after the reaction,and its performance can be regenerated through simple ***,it was confirmed by kinetic experiments that the activation of C–H at the benzyl alcohol benzylic position is the rate-determining step(RDS).According to density flooding theory calculations,Fe_(2)Ni2@CN catalysts require less energy than other materials(Fe@CN and Ni@CN)for the RDS(dehydrogenation reaction)*** N-alkylation reactions are more easily carried out on Fe_(2)Ni2@CN catalysts,which may be the reason for the best catalytic activity of Fe-Ni alloy *** carbon-coated alloy materials will show great potential in more types of heterogeneous catalysis.

关键词： iron-nickel alloy catalyst N-alkylation reaction magnetic separation reaction path dehydrogenation reaction

Photoacoustic elastography based on laser-excited shear wave

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Journal of Innovative Optical Health Sciences 2024年第3期17卷 56-72页

作者： yang Liu Ruoyi Shi gang Li Mingjian sun School of Astronautics Harbin Institute of TechnologyHarbin 150000P.R.China School of Information Science and Engineering Harbin Institute of TechnologyWeihai 264200P.R.China

Elastography can be used as a diagnostic method for quantitative characterization of tissue hardness information and thus,differential changes in pathophysiological states of *** this study,we propose a new method for shear wave elastography(SWE)based on laser-excited shear wave,called photoacoustic shear wave elastography(PASWE),which combines photoacoustic(PA)technology with ultrafast ultrasound *** using a focused laser to excite shear waves and ultrafast ultrasonic imaging for detection,high-frequency excitation of shear waves and noncontact elastic imaging can be *** laser can stimulate the tissue with the light absorption characteristic to produce the thermal expansion,thus producing the shear *** frequency of shear wave induced by laser is higher and the frequency band is *** tracking the propagation of shear wave,Young’s modulus of tissue is reconstructed in the whole shear wave propagation region to further evaluate the elastic information of *** feasibility of the method is verified by *** with the experimental results of supersonic shear imaging(SSI),it is proved that the method can be used for quantitative elastic imaging of the *** addition,compared with the SSI method,this method can realize the noncontact excitation of the shear wave,and the frequency of the shear wave excited by the laser is higher than that of the acoustic radiation force(ARF),so the spatial resolution is *** to the traditional PA elastic imaging method,this method can obtain a larger imaging depth under the premise of ensuring the imaging resolution,and it has potential application value in the clinical diagnosis of diseases requiring noncontact quantitative elasticity.

关键词： Elastography shear wave photoacoustic Young's modulus

Magmatic-tectonic response of the South China Craton to the Paleo-Pacific subduction during the Triassic:a new viewpoint based on Well NK-1

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Journal of Oceanology and Limnology 2024年第1期42卷 58-89页

作者： Chan WANG Hao LIU gang LI Zhen sun Tingting GONG Li MIAO Xiaowei ZHU Yunying ZHANG Weihai XU Wen yan Key Laboratory of Ocean and Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China Key Laboratory of Tectonic Controlled Mineralization and Oil Reservoir of Ministry of Natural Resources Chengdu University of TechnologyChengdu 610059China School of Earth Sciences and Resources China University of Geosciences(Beijing)Beijing 100083China College of Earth Science Chengdu University of TechnologyChengdu 610059China University of Chinese Academy of Sciences Beijing 100049China

The Nansha Block(NB)is one of the blocks separated from the southern margin of the South China Craton(SCC)by the western Pacific subduction,which contains rich information of geodynamic and tectonic *** reveal the essence of western Paleo-Pacific subduction during the Triassic period,Well NK-1 in this block was selected for petrographic study,and published research data from other cooperative teams were compared.A double-cycle pattern of basic to neutral magmatic volcanism was established,and 36 lithological rhythmic layers and representative cryptoexplosive breccia facies and welded tuff bands were *** with a reanalysis of published geochronological data,geochemical elements,and isotope geochemistry,we found that the rock assemblages could be divided into an intermediate-acid dacite(DA)series(SiO_(2)>65%)and basaltic(BA)series(Co<40μg/g),which was formed during the early Late Triassic((218.6±3.2)–(217.9±3.5)Ma).BA exhibits obvious calc-alkaline island-arc magmatic properties:(^(87)Sr/^(86)Sr)_i ratio ranging 0.70377–0.71118(average:0.70645),^(147)Sm/^(144)Nd ratio ranging 0.119–0.193(average:0.168),and chondrite-normalized rare earth element(REE)curves being flat,while DA exhibits remarkable characteristics of subducted island-arc andesitic magma:(^(87)Sr/^(86)Sr)_i ratio(0.70939–0.71129;average:0.71035),εNd(t)value(-6.2–-4.8;average:-5.6)andε_(Hf)(t)value(-2.9–-1.7,average:-2.2)show obvious crust-mantle mixing *** and DA reveal typical characteristics of island-arc magma systems and typeⅡenriched mantle(EM-Ⅱ)*** magma was likely resulted from the process whereby the continental crust frontal accretionary wedge was driven by the Paleo-Pacific slab subduction into the deep and began to melt,resulting in a large amount of melt(fluid)joined the asthenosphere on the side of the continental *** contrast,DA magma was likely resulted from the process whereby the plate front was forced to bend with increasing subducti

关键词： Paleo-Pacific tectonic domain tectonic evolution rift volcanic rock Nansha Block South China Craton

Continuous advantage learning for minimum-time trajectory planning of autonomous vehicles

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Science China(Information Sciences) 2024年第7期67卷 285-294页

作者： Zhuo LI Weiran WU Jialin WANG gang WANG Jian sun School of Automation Beijing Institute of Technology Beijing Institute of Technology Chongqing Innovation Center China Academy of Launch Vehicle Technology Intelligent Game and Decision Laboratory

This paper investigates the minimum-time trajectory planning problem of an autonomous vehicle. To deal with unknown and uncertain dynamics of the vehicle, the trajectory planning problem is modeled as a Markov decision process with a continuous action space. To solve it, we propose a continuous advantage learning(CAL) algorithm based on the advantage-value equation, and adopt a stochastic policy in the form of multivariate Gaussian distribution to encourage exploration. A shared actor-critic architecture is designed to simultaneously approximate the stochastic policy and the value function, which greatly reduces the computation burden compared to general actor-critic methods. Moreover, the shared actor-critic is updated with a loss function built as mean square consistency error of the advantage-value equation, and the update step is performed several times at each time step to improve data efficiency. Simulations validate the effectiveness of the proposed CAL algorithm and its better performance than the soft actor-critic algorithm.

关键词： trajectory planning continuous advantage learning stochastic policy shared actor-critic

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Efficacy of scraping therapy on blood pressure and sleep quality in stage Ⅰ and Ⅱ essential hypertension: A systematic review and meta-analysis

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Journal of Integrative Medicine 2024年第1期22卷 12-21页

作者： Zheng-gang Zhu Jian-ru Wang Xiao-yan Pan School of Nursing Hunan University of Chinese MedicineChangsha 410208Hunan ProvinceChina School of Health Sciences Universiti Sains MalaysiaKubang Kerian 16150KelantanMalaysia Department of Cardiovascular Medicine the First Affiliated Hospital of Henan University of Chinese MedicineZhengzhou 450000Henan ProvinceChina

Background Scraping therapy is widely used in treating stage I and II essential hypertension in ***,there has been no systematic evaluation of the efficacy of scraping therapy on blood pressure and sleep quality in stage I and II essential *** strategy Seven electronic databases(PubMed,Scopus,Cochrane Library,Web of Science,EBSCO,China National Knowledge Infrastructure and Wanfang Data electronic databases)were searched from inception to December *** on the principle of combining subject words with text words,the search strategy was constructed around search terms for“scraping therapy,”“scraping,”“Guasha,”“Gua sha,”“hypertension,”and“high blood pressure”during the database *** criteria Randomized controlled trials(RCTs)were included if they recruited patients with stage I and II essential hypertension and included a scraping therapy *** intervention group received antihypertensive drugs and scraping therapy,while the control group only took antihypertensive *** extraction and analysis Review Manager 5.4.0 and STATA 15.1 were used to enter all the relevant outcome variables to conduct the *** quality of the selected RCTs was assessed using the PEDro *** sensitivity analysis was carried out by iteratively excluding individual studies and repeating the analysis to determine the stability of the findings and identify any studies with greater influence on the *** analysis was performed to find the source of *** plots were used to evaluate the publication bias of included *** Nine RCTs including 765 participants were ***-analysis showed that scraping therapy combined with medication had an advantage over the use of medication alone in lowering systolic blood pressure(mean difference[MD]=?5.09,95%confidence interval[CI]=?6.50 to?3.67,P<0.001)and diastolic blood pressure(MD=?2.66,95%CI=?3.17 to?2.14,P<0.001).Subgroup analysis showed tha

关键词： Scraping therapy Essential hypertension Efficacy Blood pressure Sleep quality Systematic review Meta-analysis