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Phytochemical Screening, Study of Acute Toxicity and Hypoglycemic and Antihyperglycemic Activities of Silver Nanoparticles from Guibourtia tessmannii (Harms) J. leonard (Caesalpiniaceae)

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Open Journal of Applied Sciences 2024年第1期14卷 118-130页

作者： Ngoulé Charles Christian Eya’ane Meva François Sone Enone Bertin Ngo Nyobe Biwole Caroline Tankeu Séverin Elisée Songue Pascal Nguene Jean Pierre etame-loe gisèle Department of Pharmaceutical Sciences Faculty of Medicine and Pharmaceutical Sciences University of Douala Douala Cameroon Department of Biology of Plant Organisms Faculty of Sciences University of Douala Douala Cameroon

According to the World Health Organization, diabetes affects approximately 347 million people worldwide. Its management is not within the reach of all social classes, therefore medicinal plants are still the first resort for many populations in Africa. The biological material used in this study was the trunk bark of Guibourtia tessmannii. 50 g of trunk bark powder were decocted in 500 ml of distilled water for 5 minutes were carried out. The method used for the synthesis of silver nanoparticles (AgNps) was an organometallic bio-reduction of silver nitrate salts mediated by various secondary metabolites contained in the plant extract. The study of the toxicity acute was conducted according to guideline 423 of the OECD protocol. The pharmacological activities were each carried out with 28 female rats divided into 7 groups of four rats. It was a question for the hypoglycemic activity of administering various doses of silver nanoparticles and other substances to the rats thirty minutes after the carbohydrate intake and for the anti-hyperglycemic activity of administering the same substances to the rats thirty minutes before the carbohydrate intake. The extraction yield was 8.76%. Only the alkaloid test was negative. After acute toxicity study, the LD50 was greater than 2000 mg/kg. Blood sugar tests revealed that glibenclamide 5 mg/kg, which is the reference molecule, lowered blood sugar more than the other treatments applied in the other batches. It was followed by treatment with silver nanoparticles at a dose of 400 μg/kg in both tests. It was therefore concluded that silver nanoparticles from G. tessmannii are good for the formulation of improved traditional medicines and bring up their afficacity .

关键词： Guibourtia tessmannii Nanoparticles Hypoglycemia Anti-Hyperglycemia

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A study on wildfire impacts on greenhouse gas emissions and regional air quality in South of Orléans,France

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Journal of Environmental Sciences 2024年第1期135卷 521-533页

作者： Chaoyang Xue gisèle Krysztofiak Yangang Ren Min Cai Patrick Mercier Frédéric le Fur Corinne Robin Benoit Grosselin Véronique Daele Max RMcGillen Yujing Mu Valéry Catoire Abdelwahid Mellouki Laboratoire de Physique et Chimie de l’Environnement et de l’Espace(LPC2E) CNRS–UniversitéOrléans–CNES(UMR 7328)Orléans Cedex 245071France Institut de Combustion AérothermiqueRéactivitéEnvironnement(ICARE)CNRSOrléans Cedex 245071France Research Centre for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China Lig’Air-Association de surveillance de la qualitéde l’air en région Centre-Val de Loire Saint-Cyr-en-Val 45590France Mohammed V University RabatMorocco

Wildfire events are increasing globally which may be partly associated with climate change,resulting in significant adverse impacts on local,regional air quality and global *** September 2020,a small wildfire(burned area:36.3 ha)event occurred in Souesmes(Loiret-Cher,Sologne,France),and its plume spread out over 200 km on the following day as observed by the MODIS *** on measurements at a suburban site(~50 km northwest of the fire location)in Orléans and backward trajectory analysis,young wildfire plumes were *** increases in gaseous pollutants(CO,CH_(4),N_(2)O,VOCs,etc.)and particles(including black carbon)were found within the wildfire plumes,leading to a reduced air *** factors,defined as EF(X)=ΔX/ΔCO(where,X represents the target species),of various trace gases and black carbon within the young wildfire plumes were determined accordingly and compared with previous *** in the ambient ions(such as ammonium,sulfate,nitrate,chloride,and nitrite in the particle-and gasphase)and aerosol properties(e.g.,aerosol water content,aerosol p H)were also quantified and ***,we estimated the total carbon and climate-related species(e.g.,CO_(2),CH_(4),N_(2)O,and BC)emissions and compared them with fire emission *** biomass burning emission inventories have uncertainties in estimating small fire burned areas and *** instance,we found that the Global Fire Assimilation System(GFAS)may underestimate emissions(e.g.,CO)of this small wildfire while other inventories(GFED and FINN)showed significant *** that it is the first time to record wildfire plumes in this region,related atmospheric implications are presented and discussed.

关键词： Wildfire Air quality Emission factor Emission inventory VOLTAIRE supersite

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Nickel-based cerium zirconate inorganic complex structures for CO_(2)valorisation via dry reforming of methane

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Journal of Environmental Sciences 2024年第6期140卷 12-23页

作者： Juan Luis Martín-Espejo Loukia-Pantzechroula Merkouri Jesús Gándara-loe José Antonio Odriozola Tomas Ramirez Reina Laura Pastor-Pérez Department of Inorganic Chemistry and Material Sciences Institute of Seville University of Seville-CSICSeville 41092Spain Department of Chemical and Process Engineering University of SurreyGuildford GU27XHUnited Kingdom

The increasing anthropogenic emissions of greenhouse gases(GHG)is encouraging extensive research in CO_(2)*** reforming of methane(DRM)depicts a viable strategy to convert both CO_(2)and CH4into syngas,a worthwhile chemical *** the different active phases for DRM,the use of nickel as catalyst is economically favourable,but typically deactivates due to sintering and carbon *** stabilisation of Ni at different loadings in cerium zirconate inorganic complex structures is investigated in this work as strategy to develop robust Ni-based DRM *** and TPR-H2analyses confirmed the existence of different phases according to the Ni loading in these ***,superficial Ni is observed as well as the existence of a CeNiO_(3)perovskite *** catalytic activity was tested,proving that 10 wt.%Ni loading is the optimum which maximises *** catalyst was also tested in long-term stability experiments at 600and 800℃in order to study the potential deactivation issues at two different *** 600℃,carbon formation is the main cause of catalytic deactivation,whereas a robust stability is shown at 800℃,observing no sintering of the active phase evidencing the success of this strategy rendering a new family of economically appealing CO_(2)and biogas mixtures upgrading catalysts.

关键词： CO_(2)conversion Dry reforming of methane Nickel catalysts Pyrochlore Cerium zirconate

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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

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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(<34.8 m),MLD was more 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

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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

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A Graded Speed Control Method for Cyborg Rats Based on Electrical Stimulation of the Cuneiform Nucleus

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Journal of Bionic Engineering 2024年第3期21卷 1334-1346页

作者： Hanyi Ling le Han Nenggan Zheng Qiushi Academy for Advanced Studies(QAAS) Zhejiang UniversityHangzhou310007China The State Key Lab of Brain-Machine Intelligence Zhejiang UniversityHangzhou310007China College of Biomedical Engineering&Instrument Science Zhejiang UniversityHangzhou310007China College of Computer Science and Technology Zhejiang UniversityHangzhou310007China CCAI by MOE and Zhejiang Provincial Government(ZJU) Hangzhou310007China

The precise movement speed regulation is a key factor to improve the control effect and efficiency of the cyborg ***,the current stimulation techniques cannot realize the graded control of the *** this study,we achieved the multi-level speed regulation of cyborg rats in the large open field and treadmill by specifically targeting the Cuneiform Nucleus(CnF)of the Mesencephalic Locomotor Region(MLR).Detailed,we measured the influence of each stimulation parameter on the speed control process which included the real-time speed,accelerated speed,response time,and acceleration *** concluded that the pulse period and the pulse width were the main determinants influencing the accelerated speed of cyborg *** the amplitude of stimulation was found to affect the response time exhibited by the cyborg *** study provides valuable insights into the regulation of rat locomotion speed and highlights the potential for utilizing this approach in various experimental settings.

关键词： Cyborg rats Cuneiform nucleus Graded control Speed regulation

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Adaptive fault-tolerant control for non-minimum phase hypersonic vehicles based on adaptive dynamic programming

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Chinese Journal of Aeronautics 2024年第3期37卷 290-311页

作者： le WANG Ruiyun QI Bin JIANG State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China

In this paper,a novel adaptive Fault-Tolerant Control(FTC)strategy is proposed for non-minimum phase Hypersonic Vehicles(HSVs)that are affected by actuator faults and parameter *** strategy is based on the output redefinition method and Adaptive Dynamic Programming(ADP).The intelligent FTC scheme consists of two main parts:a basic fault-tolerant and stable controller and an ADP-based supplementary *** the basic FTC part,an output redefinition approach is designed to make zero-dynamics stable with respect to the new ***,Ideal Internal Dynamic(IID)is obtained using an optimal bounded inversion approach,and a tracking controller is designed for the new output to realize output tracking of the nonminimum phase HSV *** the ADP-based compensation control part,an ActionDependent Heuristic Dynamic Programming(ADHDP)adopting an actor-critic learning structure is utilized to further optimize the tracking performance of the HSV control ***,simulation results are provided to verify the effectiveness and efficiency of the proposed FTC algorithm.

关键词： Hypersonic vehicle Fault-tolerant control Non-minimum phase system Adaptive control Nonlinear control Adaptive dynamic programming

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Dynamic response of honeycomb-FGS shells subjected to the dynamic loading using non-polynomial higher-order IGA

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Defence Technology（防务技术） 2024年第7期37卷 149-161页

作者： Pham Binh le Trung-Thanh Tran Faculty of Mechanical Engineering Le Quy Don Technical UniversityHanoiViet Nam

The main goal of this study is to use higher-order isogeometric analysis(IGA)to study the dynamic response of sandwich shells with an auxetic honeycomb core and two different functionally graded materials(FGM)skin layers(namely honeycomb-FGS shells)subjected to dynamic ***'s non-polynomial higher-order shear deformation theory(HSDT)is used due to its simplicity and *** governing equation is derived from Hamilton's *** verifying the present approach,the effect of input parameters on the dynamic response of honeycomb-FGS shells is carried out in detail.

关键词： IGA Elastic foundation Dynamic response FGM Auxetic honeycomb Shell

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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

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