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Fast synthesis of gold nanoparticles by cold atmospheric pressure plasma jet in the presence of Au^(+) ions and a capping agent

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Plasma Science and Technology 2024年第7期26卷 108-115页

作者： Tatiana HABIB José Mauricio A.CAIUT Bruno CAILLIER Laboratoire Diagnostics des Plasmas Hors Equilibre(DPHE) Universitéde ToulouseINU ChampollionAlbi 81000France Department of Chemistry The Nanomaterials and Luminescent Systems GroupFaculty of PhilosophyScience and Letters at Ribeirão PretoUniversity of São PauloRibeirão Preto-SP 14040-901Brazil

Homogeneous gold nanoparticles were synthesized under atmospheric pressure using a nonthermal helium plasma jet in a single-step process.A current power supply was used to generate the plasma discharge rich in diverse reactive *** species induce rapid chemical reactions responsible for the reduction of the gold salts upon contact with the liquid *** this study,spherical and monodispersed gold nanoparticles were obtained within 5 min of plasma exposure using a solution containing gold(Ⅲ)chloride hydrate(HAuCl_(4))as a precursor and polyvinylpyrrolidone(PVP)as a capping agent to inhibit *** formation of these metal nanoparticles was initially perceptible through a visible change in the sample's color,transitioning from light yellow to a red/pink *** was subsequently corroborated by UVvis spectroscopy,which revealed an optical absorption in the 520-550 nm range for Au NPs,corresponding to the surface plasmon resonance(SPR)*** investigation into the impact of various parameters,including plasma discharge duration,precursor and capping agent concentrations,was carried out to optimize conditions for the formation of well-separated,spherical gold *** light scattering(DLS)was used to measure the size of these nanoparticles,transmission electron microscopy(TEM)was used to observe their morphology and X-ray diffraction(XRD)was also employed to determine their crystallographic *** results confirm that homogeneous spherical gold nanoparticles with an average diameter of 13 nm can be easily synthesized through a rapid,straightforward,and environmentally friendly approach utilizing a helium atmospheric pressure plasma.

关键词： gold nanoparticles non-thermal plasma jet helium DBD

Intelligent Machine Learning Based Brain Tumor Segmentation through Multi-Layer Hybrid U-Net with CNN Feature Integration

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Computers, Materials & Continua 2024年第4期79卷 1301-1317页

作者： Sharaf J.Malebary Department of Information Technology Faculty of Computing and Information TechnologyKing Abdulaziz UniversityP.O.Box 344Rabigh21911Saudia Arabia

Brain tumors are a pressing public health concern, characterized by their high mortality and morbidity ***, the manual segmentation of brain tumors remains a laborious and error-prone task, necessitatingthe development of more precise and efficient methodologies. To address this formidable challenge, we proposean advanced approach for segmenting brain tumorMagnetic Resonance Imaging (MRI) images that harnesses theformidable capabilities of deep learning and convolutional neural networks (CNNs). While CNN-based methodshave displayed promise in the realm of brain tumor segmentation, the intricate nature of these tumors, markedby irregular shapes, varying sizes, uneven distribution, and limited available data, poses substantial obstacles toachieving accurate semantic segmentation. In our study, we introduce a pioneering Hybrid U-Net framework thatseamlessly integrates the U-Net and CNN architectures to surmount these challenges. our proposed approachencompasses preprocessing steps that enhance image visualization, a customized layered U-Net model tailoredfor precise segmentation, and the inclusion of dropout layers to mitigate overfitting during the training ***, we leverage the CNN mechanism to exploit contextual information within brain tumorMRI images,resulting in a substantial enhancement in segmentation *** experimental results attest to the exceptionalperformance of our framework, with accuracy rates surpassing 97% across diverse datasets, showcasing therobustness and effectiveness of our approach. Furthermore, we conduct a comprehensive assessment of ourmethod’s capabilities by evaluating various performance measures, including the sensitivity, Jaccard-index, andspecificity. our proposed model achieved 99% accuracy. The implications of our findings are profound. Theproposed Hybrid U-Net model emerges as a highly promising diagnostic tool, poised to revolutionize brain tumorimage segmentation for radiologists and clinician

关键词： Brain tumor Hybrid U-Net CLAHE transfer learning MRI images

Mafic and felsic magmatism in the Wadi Kalalat area, South Eastern Desert, Egypt: mineralogy, geochemistry and geodynamic evolution during the Neoproterozoic in the Nubian Shield

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Acta Geochimica 2024年第1期43卷 150-173页

作者： Adel A.Surour Ahmed A.Madani Mohamed A.El-Sobky faculty of Science Galala UniversityNew Galala CitySuez 43511Egypt Department of Geology Faculty of ScienceCairo UniversityGiza 12613Egypt Egyptian Mineral Resources Authority P.O.Box 11517AbbasiyaCairoEgypt

In the south Eastern Desert of Egypt,two contrasting types of magmatism(mafic and felsic) are recorded in the Wadi Kalalat area,and form the Gabal El Motaghiarat and Gabal Batuga intrusions,*** two intrusions post-dates ophiolitic and arc associations represented by serpentinite and metagabbro-diorite,*** mafic intrusion has a basal ultramafic member represented by fresh peridotite,which is followed upward by olivine gabbro and anorthositic or *** mafic intrusion pertains to the Alaskan-type mafic-ultramafic intrusions in the Arabian-Nubian Shield(ANS)being of tholeiitic nature and emplaced in a typical arc *** the other hand,the Gabal Batuga intrusion comprises three varieties of fresh A-type granites of high K-calc alkaline nature,which is peraluminous and garnetbearing in parts.A narrow thermal aureole in the olivine gabbro of the mafic intrusion was developed due to the intrusion of the Batuga *** results in the development of a hornfelsic melagabbro variety in which the composition changed from tholeiitic to a calc-alkaline composition due to the addition of S_(i)o_(2),Al_(2)o_(3),alkalis,lithosphile elements(LILEs) such as Rb(70 ppm) and Y(28 ppm) from the felsic *** the thermal aureole,Rb amounts 2-8 ppm and Y lies in the range on started to emplace during the waning stage of an arc system,with transition from the pre-collisional(i.e.,arc setting) to post-collisional and within plate *** from which the Gabal Batuga granites were fractionated is high-K calc-alkaline giving rise to a typical post-collisional A-type granite(A_(2)-subtype) indicating an origin from an underplating crustal ***,it is stressed here that the younger granites in the ANS are not exclusively post-collisional and within-plate but most likely they started to develop before closure of the arc *** possible source(s) of mafic magmas

关键词： Wadi Kalalat Gabal El Motaghairat mafic intrusion Gabal Batuga felsic intrusion Arc setting Post-collision Within-plate

Differential roles of C-3 and C-6 phosphate monoesters in affecting potato starch properties

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Grain & oil Science and Technology 2024年第2期7卷 79-86页

作者： Li Ding Andreas Blennow Yuyue Zhong Department of Plant and Environmental Sciences Faculty of ScienceUniversity of CopenhagenDenmark Department of Sustainable and bio-inspired Materials Max-Planck Institute of Colloids and InterfacesPotsdamGermany

The effects of starch phosphate monoester content(SPC),namely C-3(C3P)and C-6 phosphate monoesters(C6P),on the starch properties were investigated using four potato starches with varied SPC/C3P/C6P and two nonphosphorylated maize starches with a similar range of amylose content(AC)as *** starch property results showed that a higher SPC is associated with lower turbidity,storage and loss modulus after storage,and water solubility,but higher swelling power(SP)and pasting *** findings suggested that SPC inhibited molecular rearrangement during storage and starch leaching during heating,and enhanced swelling and viscosities due to increased hydration and water uptake caused by the repulsion effect of phosphate groups and a less ordered crystalline *** SPC also resulted in lower resistant starch(RS)content in a native granular state but higher RS after *** correlations further indicated that SPC/C3P/C6P were positively correlated with peak(r^(2)=0.925,0.873 and 0.930,respectively),trough(r^(2)=0.994,0.968 and 0.988,respectively),and final viscosities(r^(2)=0.981,0.968 and 0.971,respectively).Notably,SPC,mainly C3P,exhibited a significantly positive correlation with SP(r^(2)=0.859)and setback viscosity(r^(2)=0.867),whereas SPC,mainly C6P,showed a weak positive correlation with RS after retrogradation(r^(2)=0.746).However,SPC had no significant correlations with water solubility,turbidity and rheology properties,which were more correlated with *** findings are helpful for the food industry to select potato starches with desired properties based on their contents of SPC,C3P,or C6P.

关键词： Starch phosphate monoesters C-3 phosphate monoesters C-6 phosphate monoesters Physicochemical properties In vitro digestibility

AI-Driven Learning Management Systems:Modern Developments, Challenges and Future Trends during theAge of ChatGPT

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Computers, Materials & Continua 2024年第8期80卷 3289-3314页

作者： Sameer Qazi Muhammad Bilal Kadri Muhammad Naveed Bilal AKhawaja Sohaib Zia Khan Muhammad Mansoor Alam Mazliham Mohd Su’ud Department of Computer Science Faculty of EngineeringScience and TechnologyIQRA UniversityKarachi75500Pakistan College of Computer and Information Sciences Prince Sultan UniversityRiyadh11586Saudi Arabia faculty of Engineering Department of Electrical EngineeringIslamic University of MadinahP.O.BOX 170Madinah41411Saudi Arabia faculty of Engineering Department of Mechanical EngineeringIslamic University of MadinahP.O.BOX 170Madinah41411Saudi Arabia faculty of Computing Riphah International UniversityIslamabad46000Pakistan faculty of Computing and Informatics(FCI)Multimedia University Cyberjaya63100Malaysia faculty of Engineering and Information Technology School of Computer ScienceUniversity of Technology SydneySydneyNSW 2007Australia

CoVID-19 pandemic restrictions limited all social activities to curtail the spread of the *** foremost and most prime sector among those affected were schools,colleges,and *** education system of entire nations had shifted to online education during this *** shortcomings of Learning Management Systems(LMSs)were detected to support education in an online mode that spawned the research in Artificial Intelligence(AI)based tools that are being developed by the research community to improve the effectiveness of *** paper presents a detailed survey of the different enhancements to LMSs,which are led by key advances in the area of AI to enhance the real-time and non-real-time user *** AI-based enhancements proposed to the LMSs start from the Application layer and Presentation layer in the form of flipped classroom models for the efficient learning environment and appropriately designed UI/UX for efficient utilization of LMS utilities and resources,including AI-based *** layer enhancements are also required,such as AI-based online proctoring and user authentication using *** extend to the Transport layer to support real-time and rate adaptive encrypted video transmission for user security/privacy and satisfactory working of *** also needs the support of the Networking layer for IP-based geolocation features,the Virtual Private Network(VPN)feature,and the support of Software-Defined Networks(SDN)for optimum Quality of Service(QoS).Finally,in addition to these,non-real-time user experience is enhanced by other AI-based enhancements such as Plagiarism detection algorithms and Data Analytics.

关键词： Learning management systems chatbots ChatGPT online education Internet of Things(IoT) artificial intelligence(AI) convolutional neural networks natural language processing

Chemically Mediated Interactions between Grapevine, Aphid, Ladybird, and Ant in the Context of Insect Chemical Ecology

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Phyton-International Journal of Experimental Botany 2024年第7期93卷 1523-1542页

作者： Taghreed Alsufyani Noura J.Alotaibi Nour Houda M’sakni Mona A.Almalki Eman M.Alghamdi Department of Chemistry College of ScienceTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Department of biology College of ScienceTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Chemistry Department Faculty of ScienceKing AbdulAziz UniversityP.O.Box 80200Jeddah21589Saudi Arabia

This study simpliﬁes the complex relationship among grapevine plants,aphids,ladybirds,and ants,which is essential for effective pest management and ecological *** study investigated the impact of aphid attacks and the presence of ants and ladybirds on the volatile compounds proﬁle released into the chemosphere of the community consisting of the common vine Vitis vinifera,the aphid Aphis illinoisensis,the ladybird Cocci-nella undecimpunctata-and the ant Tapinoma *** study aims to analyze the volatile compounds emitted by the grapevine and surrounding insects in response to these intricate *** extraction of volatile organic compounds(VoCs)was carried out using closed-loop stripping(CLS)and then analyzed via gas chromatography-mass spectrometry(GC-MS)and principles coordinated analysis(PCA)was *** grapevine was exposed to different types and order of treatments,including non-infested,aphid-infested,aphid-infested with ant,aphid-infested with ladybird,and various combinations of ant and *** the aphid attack,the outcomes uncovered massive alterations in the volatile compound proﬁ*** grapevine displayed distinct emissions of germacrene D,an alcohol,and an alkene compared to non-infested *** characteristic VoC proﬁle was the share of infested grapes in the presence of ants,with benzene derivatives and sesquiterpenes dominating the *** coexistence of ladybirds with ants and aphids resulted in a dif-ferent volatile proﬁle characterized by elevated levels of aldehydes,ketones,α-farnesene,and its hydroxy *** was concluded that the emission of VoCs into the chemosphere of the grapevine communities varied qualitatively and quantitatively depending on the level of the relationship complexity within each community in response to the infestation of grapevines by aphids,the presence of ladybirds as natural predators,and the presence of ant as *** grapevine’s status-dependent compounds

关键词： Aphids Aphis illinoisensis volatile organic compounds chemosphere pest management gas chromatography-mass spectrometry closed-loop stripping

A new fractional order 6D chaotic model:Study of model dynamics,system structure graph,electronic circuit realization and fractional control

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Journal of ocean Engineering and Science 2024年第2期9卷 112-125页

作者： M.Higazy Norah Almalki Shabbir Muhammad A.Al-Ghamdi Department of Mathematics and Statistics College of ScienceTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia Department of Physics and Engineering Mathematics Faculty of Electronic EngineeringMenoufia UniversityMenouf 32952Egypt Research Center for Advanced Materials Science(RCAMS) King Khalid UniversityP.O.Box 9004Abha 61413Saudi Arabia Department of Chemistry College of ScienceKing Khalid UniversityP.O.Box 9004Abha 61413Saudi Arabia Department of Physics Faculty of ScienceKing Abdulaziz UniversityP.O.Box 80203Jeddah 21589Saudi Arabia

A new fractional 6D chaotic model is constructed in this *** new fractional 6D chaotic model has six positive parameters plus the fractional order with eight nonlinear *** complicated chaotic dy-namics of the new fractional 6D model is presented and *** basic properties of this model are studied and its chaotic attractors,dissipative feature,symmetry,equilibrium points,Lyapunov Exponents are *** new dynamics of the 6D fractional model is numerically simulated using Matlab *** addition,utilizing the graph theory tools certain structural characteristics are *** electrical circuit is built to implement the new 5.4 fractional order 6D ***,an active fractional order controller is proposed to control the new model at different fractional *** chaos of the new model is very useful and can be used to produce random keys for data encryption.

关键词： Chaotic systems Fractional calculus Lyapunov exponents Chaotic attractors Adjacency matrix Hermitian matrix Electronic circuit realization

Disentangling the effects of management and climate change on habitat suitability for saproxylic species in boreal forests

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Journal of Forestry Research 2024年第2期35卷 121-133页

作者： Ellinoora Ekman María Triviño Clemens Blattert Adriano Mazziotta Maria Potterf Kyle Eyvindson Department of biological and Environmental Science University of JyvaskylaP.O.Box 3540014 JyvaskylaFinland Institute for Atmospheric and Earth System Research(INAR)/Physics Faculty of ScienceUniversity of HelsinkiP.O.Box 6800014 HelsinkiFinland School of Resource Wisdom University of JyvaskylaP.O.Box 3540014 JyvaskylaFinland Natural Resources Institute Finland(LUKE) Latokartanonkaari 900790 HelsinkiFinland Ecosystem Dynamics and Forest Management Group Technical University of MunichHans‑Carl‑Von‑Carlowitz‑Platz 285354 FreisingGermany faculty of Environmental Sciences and Natural Resource Management Norwegian University of Life SciencesP.O.Box 50031433ÅsNorway

Forest degradation induced by intensive forest management and temperature increase by climate change are resulting in biodiversity decline in boreal *** forest management and high-end climate emission scenarios can further reduce the amount and diversity of deadwood,the limiting factor for habitats for saproxylic species in European boreal *** magnitude of their combined effects and how changes in forest management can affect deadwood diversity under a range of climate change scenarios are poorly *** used forest growth simulations to evaluate how forest management and climate change will individually and jointly affect habitats of red-listed saproxylic species in *** simulated seven forest management regimes and three climate scenarios(reference,RCP4.5 and RCP8.5)over 100 *** regimes included set aside,continuous cover forestry,business-as-usual(BAU)and four modifications of *** suitability was assessed using a speciesspecific habitat suitability index,including 21 fungal and invertebrate species groups.“Winner”and“loser”species were identified based on the modelled impacts of forest management and climate change on their habitat *** found that forest management had a major impact on habitat suitability of saproxylic species compared to climate *** suitability index varied by over 250%among management regimes,while overall change in habitat suitability index caused by climate change was on average only 2%.More species groups were identified as winners than losers from impacts of climate change(52%–95%were winners,depending on the climate change scenario and management regime).The largest increase in habitat suitability index was achieved under set aside(254%)and the climate scenario RCP8.5(>2%),while continuous cover forestry was the most suitable regime to increase habitat suitability of saproxylic species(up to+11%)across all climate change *** results show that close-to-na

关键词： biodiversity Simulations Finland Forest planning Habitat suitability Deadwood

Principles of Technology for Bottling Medicinal Mineral Waters of Sairme Using the Example of Source №3a

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American Journal of Analytical Chemistry 2024年第4期15卷 135-138页

作者： Irina Nikolaishvili Giorgi Kvartskava faculty of Agriculture Sciences and bio-Systems Engineering Georgian Technical University Tbilisi Georgia

Sairme mineral water, one of the famous mineral waters in Georgia, is renowned for its exceptional healing properties. The distinctiveness and therapeutic benefits of the naturally sourced mineral water, known as “Sairme”, stem from its rich array of microelements, notably including iron and manganese. Since 1948, the bottling of Sairme mineral water has been a prominent activity. Named after the Sairme deposit, this mineral water is packaged in various formats to cater to diverse consumer preferences. The bottling process involves transporting the mineral water from wells to the bottling plant through pipelines. Prior to bottling, the mineral water undergoes meticulous processing stages in adherence to current Georgian and international regulations. This process ensures that the concentration of trace elements in the bottled water is minimized, maintaining its purity and quality. Given the importance of preserving the microelements present in bottled mineral water, our research is dedicated to optimizing the technological process. our objective is to safeguard the valuable microelements while ensuring the highest standards of quality and safety in the final product.

关键词： Sairme Mineral Water Deposit oxidation-Reduction Potential Trace Elements Chemical Composition Seasonality