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International Journal of Organic Chemistry 2024年第3期14卷 107-122页

作者： Marwa Dhiabi Sirine Karoui Mehdi Fakhfakh Souhir Abid Emmanuelle Limanton rémy le guével Thierry Charlier Ludovic Paquin Jean-Pierre Bazureau Houcine Ammar Laboratoire de Chimie Applique: Htrocycles Corps et Polymres Facult des Sciences de Sfax Universit de Sfax Sfax Tunisie Institut des Sciences Chimiques de rennes Universit de Rennes Campus de Beaulieu Rennes Cedex France Department of Chemistry (Science and Arts): Al Qurayat Al-Jouf University Al Jawf Saudi Arabia S2Wave Platform ScanMAT UAR CNRS Universit de Rennes Campus de Beaulieu Rennes Cedex France ImPACcell Platform Biosit SFR UMS CNRS Inserm Campus de Villejean Rennes France Institut de recherche en Sant Environnement et Travail IRSET Inserm UMR_S Rennes France

The synthesis of new 4-imino-4H-chromeno[2,3-d]pyrimidin-3(5H)-amine in four steps including one step under microwave dielectric heating is reported. The structural identity of the synthesized compounds was established according to their spectroscopic analysis, such as FT-Ir, NMr and mass spectroscopy. These new compounds were tested for their antiproliferative activities on seven representative human tumoral cell lines (Huh7 D12, Caco2, MDA-MB231, MDA-MB468, HCT116, PC3 and MCF7) and also on fibroblasts. Among them, only the compounds 6c showed micromolar cytotoxic activity on tumor cell lines (1.8 50 50 > 25 μM). Finally, in silico ADMET studies ware performed to investigate the possibility of using of the identified compound 6c as potential anti-tumor compound.

关键词： 2-Amino-4H-Chromene 4H-Chromeno[2 3-d]Pyrimidin-3(5H)-Amine Microwave Irradiation Tumoral Cell Line in Silico ADMET

Synthesis of New 2-Phenylamino-4<i>H</i>-chromene-3-carbonitrile Derivatives and Their Effects on Tumor Cell Lines and against Protein Kinases

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International Journal of Organic Chemistry 2020年第2期10卷 88-103页

作者： Ali Bouattour Mehdi Fakhfakh Souhir Abid Ludovic Paquin rémy le guével Thierry Charlier Sandrine ruchaud Stéphane Bach Jean-Pierre Bazureau Houcine Ammar Laboratoire de Chimie Appliquée: Hétérocycles Corps Gras et Polymères Faculté des Sciences de Sfax Université de Sfax Sfax Tunisie Département de Chimie Collège des Sciences et des Arts Université de Jouf Al Qurayyat KSA Institut des Sciences Chimiques de rennes (ISCr) UMR CNRS 6226 Université de Rennes 1 Campus de Beaulieu Rennes France S2 Wave Platform ScanMAT UMS 2001CNRS Université de Rennes 1 Campus de Beaulieu Rennes France Université de rennes 1 ImPACcell Platform Campus Villejean Rennes France Sorbonne Universités UPMC Université Paris 06 CNRS USR3151 Protein Phosphorylation and Human Disease Unit KISSf Platform Station Biologique Place Georges Teissier Roscoff France

The synthesis of 2-phenylimino-4H-chromene-3-carbonitriles 6(a-d) in good overall yields using an efficient and practical methodology in 3 steps has been implemented in this present work. The first step was a heterocy... 详细信息

The synthesis of 2-phenylimino-4H-chromene-3-carbonitriles rong>6(a-d)rong> in good overall yields using an efficient and practical methodology in 3 steps has been implemented in this present work. The first step was a heterocyclization between 2-hydroxybenzaldehyde rong>1rong> and propanedinitrile rong>2rong> which produced 2-iminocoumarin rong>3rong> which was submitted to nitrogen/nitrogen displacement in the presence of aromatic primary amine rong>4rong>. In the third step, reduction of rong>5rong> led to the desired 2-phenylimino-4H-chromene-3-carbonitriles rong>6rong>. Compounds rong>5(a-d)rong> and rong>6(a-d)rong> were evaluated for their potential in vitro cytotoxicity against six selected tumor cell lines (Huh7-D12, Caco2, MDA-MB231, HCT 116, PC3 and NCI-H727) and tested for their protein kinase inhibition on eight selected protein kinases. Among them, compounds rong>5crong> and rong>6brong> exhibited inhibition on HsCK1e (rong>5crong>: 44% and rong>6brong>: 42% at 1 μM) and rong>5c rong>for cytotoxicity on PC3 cell lines (63% at 25 μM).

关键词： Iminocoumarin 2H-benzopyran 2-Imino-2H-benzopyran 4H-chromene 2-Amino-4H-chromene Nitrogen/Nitrogen Displacement Protein Kinase Inhibition Cytotoxicity

rethinking multi-spatial information for transferable adversarial attacks on speaker recognition systems

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CAAI Transactions on Intelligence Technology 2024年第3期9卷 620-631页

作者： Junjian Zhang Hao Tan le Wang Yaguan Qian Zhaoquan gu guangzhou University GuangzhouChina Department of New Networks Peng Cheng LaboratoryShenzhenChina Harbin Institute of Technology(Shenzhen) ShenzhenChina Zhejiang University of Science and Technology HangzhouChina

Adversarial attacks have been posing significant security concerns to intelligent systems,such as speaker recognition systems(SrSs).Most attacks assume the neural networks in the systems are known beforehand,while black-box attacks are proposed without such information to meet practical *** black-box attacks improve trans-ferability by integrating multiple models or training on multiple datasets,but these methods are *** by the optimisation strategy with spatial information on the perturbed paths and samples,we propose a Dual Spatial Momentum Iterative Fast Gradient Sign Method(DS-MI-FGSM)to improve the transferability of black-box at-tacks against ***,DS-MI-FGSM only needs a single data and one model as the input;by extending to the data and model neighbouring spaces,it generates adver-sarial examples against the integrating *** reduce the risk of overfitting,DS-MI-FGSM also introduces gradient masking to improve *** authors conduct extensive experiments regarding the speaker recognition task,and the results demonstrate the effectiveness of their method,which can achieve up to 92%attack success rate on the victim model in black-box scenarios with only one known model.

关键词： speaker recognition spoofing attacks

Unveiling the intrinsic properties of single NiZnFeO_x entity for promoting electrocatalytic oxygen evolution

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Chinese Chemical letters 2024年第4期35卷 181-186页

作者： Zhihao gu Jiabo le Hehe Wei Zehui Sun Mahmoud Elsayed Hafez Wei Ma Key Laboratory for Advanced Materials and Joint International research Laboratory of Precision Chemistry and Molecular Engineering Feringa Nobel Prize Scientist Joint Research CenterFrontiers Science Center for Materiobiology and Dynamic ChemistrySchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China Ningbo Institute of Materials Technology and Engineering Chinese Academy of SciencesNingbo 315201China Department of Chemistry Faculty of ScienceBeni-Suef UniversityBeni-Suef 62511Egypt

Although considerable research efforts have been devoted to the design and development of non-noble electrocatalysts for oxygen evolution reaction(OEr), substantial enhancement of OEr performance with commercial-scale water electrolysis remains a big challenge. This could result from the difficulties in detecting the intrinsic properties and overlooking the assembly process for electrochemical OEr process. Here, we employ a microjet collision method to investigate the intrinsic OEr activities of individual NiZnFeO_x entities with and without a moderate magnetic field. Our results demonstrate that single NiZnFeO_x nanoparticles(NPs) show the excellent OEr performance with a lowest onset potential(~1.35 V vs. rHE) and a greatest magnetic enhancement(~118%) among bulk materials, single agglomerations and NPs. Furthermore, we explore the utility of theoretical investigation by density functional theory(DFT)calculations for studying OEr process on NiZnFeO_x surfaces without and with spin alignment, indicating monodispersed NiZnFeO_xNPs with totally spin alignment facilitates the OEr process under the external magnetic field. It is found that the well-dispersion of NiZnFeO_x NPs would increase the electrical conductivity and the surface spin state, resulting in promoting their OEr activities. This work provides a test for uncovering the essential roles of NPs assembly to a significant promotion of their magnet-assisted OEr.

关键词： Single entity OEr Magnetic enhancement Electrocatalysis Well-dispersion

An Analysis of the Fragmentation of Observing Time At the Muztagh-Ata Site

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research in Astronomy and Astrophysics 2024年第3期24卷 29-33页

作者： Wen-Bo gu Jing Xu guo-Jie Feng Xuan Zhang le-Tian Wang Xin-Liang Wang Ali Esamdin Li-Xian Shen Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 83001lChina School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China

Cloud cover plays a pivotal role in assessing observational conditions for astronomical *** for the fraction of observing time,its fragmentation also wields a significant influence on the quality of nighttime sky *** this article,we introduce the functionΓ∈[0,1],designed to comprehensively capture both the fraction of available observing time and its *** in situ measurement data gathered at the Muztagh-Ata site between 2017 and 2021,we showcase the effectiveness of our *** statistical result illustrates that the Muztagh-Ata site affords approximately 122 nights that were absolutely clear and 205 very good nights annually,corresponding toΓ≥0.9 andΓ≥0.36 respectively.

关键词： site testing-atmospheric effects-methods statistical

Synthesis of hierarchically porous carbon materials by zinc salts-assisted carbonization of biomass and organic solid wastes

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Particuology 2024年第1期84卷 45-52页

作者： le-le Zhang lei Tong Yanwei Ding Wanqun Zhang Hai-Wei Liang Hefei National research Center for Physical Sciences at the Microscale Department of ChemistryUniversity of Science and Technology of ChinaHefei230026China

Hierarchically porous carbons(HPCs)with multimodal pores have attracted considerable attention due to their unique physical and chemical properties and various application potentials in heterogeneous catalysis,environmental treatment,and energy storage and ***,we report a general and simple zinc salts-assisted method for the synthesis of HPCs with varied porosity and chemical func-tionalities by the direct carbonization of diverse biomass and *** the carbonization,zinc salts are thermally decomposed into nanoparticles that serve as in-situ templates to introduce nanopores in *** prepared HPCs exhibit high specific surface areas(up to 2432 m2 g-1),large pore volumes(up to 4.30 cm^(3)g^(-1)),and broad pore size ***,the zinc salts can be recovered and recycled,supporting the sustainable production of HPCs on large *** prepared HPCs-supported catalysts with atomically dispersed metal sites exhibit promising electrocatalytic performance for the oxygen reduction reaction.

关键词： Hierarchical porous carbon Zinc salts Biomass Wastes Electrocatalysis

Contrasting physical mechanisms of yellowfin tuna fluctuations between the western and eastern Indian Ocean

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Journal of Oceanology and Limnology 2024年第3期42卷 960-971页

作者： Peng LIAN le GAO Key Laboratory of Ocean Observation and Forecasting and Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China Laboratory for Ocean Dynamics and Climate Laoshan LaboratoryQingdao 266061China

As an economically critical pelagic migratory species,yellowfin tuna(Thunnus albacores,YFT)is very sensible to physical and environmental conditions,such as sea surface temperature(SST),ocean heat content(OHC),and the mixed layer depth(MLD).We investigated the impact of SST,OHC,and MLD on fluctuations of YFT catch in the western/eastern Indian Ocean using the long time series of 63-year environmental and YFT *** found that the impact of SST on YFT was heavily overestimated in the past,and MLD plays a more critical role in the YFT catch *** the MLD deepens(>34.8 m),SST was more influential in predicting the catches of YFT than OHC in the western Indian Ocean,and OHC was more critical to YFT than SST in the eastern Indian ***,when the MLD shallows(re vital to predict the catch per unit effort(CPUE)of YFT than SST/OHC in the *** 2000,there was an asynchronous pattern of YFT CPUE induced by higher frequency variations and ocean hiatus of SST/OHC signals in the western and eastern Indian Oceans *** impact of the subsurface hiatus may induce the decrease of YFT in the eastern Indian *** above findings clarified a non-stationary relationship between the environmental factors and catches of YFT and provided new insights into variations in YFT abundance.

关键词： yellowfin tuna Indian Ocean sea surface temperature(SST) ocean heat content(OHC) mixed layer depth(MLD) hiatus

Impacts of central-Pacific El Niño and physical drivers on eastern Pacific bigeye tuna

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Journal of Oceanology and Limnology 2024年第3期42卷 972-987页

Bigeye tuna Thunnus obesus is an important migratory species that forages deeply,and El Niño events highly influence its distribution in the eastern Pacific *** sea surface temperature is widely recognized as the main factor affecting bigeye tuna(BET)distribution during El Niño events,the roles of different types of El Niño and subsurface oceanic signals,such as ocean heat content and mixed layer depth,remain *** conducted A spatial-temporal analysis to investigate the relationship among BET distribution,El Niño events,and the underlying oceanic signals to address this knowledge *** used monthly purse seine fisheries data of BET in the eastern tropical Pacific Ocean(ETPO)from 1994 to 2012 and extracted the central-Pacific El Niño(CPEN)indices based on Niño 3 and Niño ***,we employed Explainable Artificial Intelligence(XAI)models to identify the main patterns and feature importance of the six environmental variables and used information flow analysis to determine the causality between the selected factors and BET ***,we analyzed Argo datasets to calculate the vertical,horizontal,and zonal mean temperature differences during CPEN and normal years to clarify the oceanic thermodynamic structure differences between the two types of *** findings reveal that BET distribution during the CPEN years is mainly driven by advection feedback of subsurface warmer thermal signals and vertically warmer habitats in the CPEN domain area,especially in high-yield fishing *** high frequency of CPEN events will likely lead to the westward shift of fisheries centers.

关键词： bigeye tuna central-Pacific El Niño(CPEN) ocean heat content Argo explainable artificial intelligence(XAI) information flow

regulation of insect behavior by non-coding rNAs

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Science China(Life Sciences) 2024年第6期67卷 1106-1118页

作者： Jing He le Kang State Key Laboratory of Integrated Management of Pest Insects and rodents Institute of ZoologyChinese Academy of SciencesBeijing 100101China Beijing Institutes of Life Sciences Chinese Academy of SciencesBeijing 100101China College of Life Science Hebei UniversityBaoding 071002China

The adaptation of insects to environments relies on a sophisticated set of behaviors controlled by molecular and physiological *** the past several decades,accumulating studies have unveiled the roles of non-coding rNAs(nc rNAs)in regulating insect *** rNAs assume particularly pivotal roles in the behavioral plasticity of insects by rapidly responding to environmental *** rNAs also contribute to the maintenance of homeostasis of insects by fine-tuning the expression of target ***,a comprehensive review of nc rNAs'roles in regulating insect behaviors has yet to be ***,we present the recent progress in our understanding of how nc rNAs regulate various insect behaviors,including flight and movement,social behavior,reproduction,learning and memory,and *** refine the intricate mechanisms by which nc rNAs modulate the function of neural,motor,reproductive,and other physiological systems,as well as gene expression in insects like fruit flies,social insects,locusts,and ***,we discuss potential avenues for future studies in nc rNA-mediated insect behaviors.

关键词： ncrNAs insect behavior plasticity fine-tuning environmental adaptation

Machine learning based models for predicting compressive strength of geopolymer concrete

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 1028-1049页

作者： Quang-Huy le Duy-Hung NguYEN Thanh SANG-TO Samir KHATIr Hoang le-MINH Amir H.GANDOMI Thanh CUONG-le Center for Engineering Application and Technology Solutions Ho Chi Minh City Open UniversityHo Chi Minh 700000Vietnam Institute of Civil Engineering Ho Chi Minh City University of TransportHo Chi Minh 700000Vietnam Faculty of Engineering&Information Technology University of Technology SydneyUltimoNSW 2007Australia

recently,great attention has been paid to geopolymer concrete due to its advantageous mechanical and environmentally friendly *** effort has been made in experimental studies to advance the understanding of geopolymer concrete,in which compressive strength is one of the most important *** facilitate engineering work on the material,an efficient predicting model is *** this study,three machine learning(ML)-based models,namely deep neural network(DNN),K-nearest neighbors(KNN),and support vector machines(SVM),are developed for forecasting the compressive strength of the geopolymer concrete.A total of 375 experimental samples are collected from the literature to build a database for the development of the predicting models.A careful procedure for data preprocessing is implemented,by which outliers are examined and removed from the database and input variables are standardized before feeding to the fitting *** standard K-fold cross-validation approach is applied for evaluating the performance of the models so that overfitting status is well managed,thus the generalizability of the models is *** effectiveness of the models is assessed via statistical metrics including root mean squared error(rMSE),mean absolute error(MAE),correlation coefficient(r),and the recently proposed performance index(PI).The basic mean square error(MSE)is used as the loss function to be minimized during the model fitting *** three ML-based models are successfully developed for estimating the compressive strength,for which good correlations between the predicted and the true values are obtained for DNN,KNN,and *** numerical results suggest that the DNN model generally outperforms the other two models.

关键词： geopolymer concrete compressive strength prediction machine-learning based model deep neural network K-nearest neighbor support vector machines