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Nanotechnology-enabled delivery of phytoconstituents:Recent developments,applications,and regulatory considerations
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作者 MohdDanish Ansari Haya Majid +4 位作者 Syed Mahmood Zarif Mohamed Sofian Asif Husain Yasmin Sultana Faiyaz Shakeel 《Asian Pacific Journal of Tropical Biomedicine》 2026年第1期1-23,共23页
Nanotechnology has revolutionized drug delivery,particularly through nanoformulations of phytoconstituents,enhancing their therapeutic potential.Despite their broad bioactivities,plant-based compounds often suffer fro... Nanotechnology has revolutionized drug delivery,particularly through nanoformulations of phytoconstituents,enhancing their therapeutic potential.Despite their broad bioactivities,plant-based compounds often suffer from poor bioavailability and stability.Nanoformulations address these limitations by improving solubility,targeted delivery,and controlled release.This approach opens new possibilities for treating chronic diseases like cancer,diabetes,and neurodegenerative disorders.This review aims to examine recent advancements in nanotechnology-based formulation strategies designed to enhance the delivery,stability,and therapeutic efficacy of phytochemicals and also discusses regulatory issues,safety concerns,scalability,and cost-effectiveness.Emphasis was placed on nanoformulation techniques employed for key phytoconstituents such as curcumin,resveratrol,epigallocatechin gallate,and quercetin.The most commonly employed nanocarriers included polymeric nanoparticles,solid lipid nanoparticles,and liposomes.These formulations significantly improved the solubility,stability,and controlled release profiles of phytochemicals.In vitro and in vivo studies demonstrated enhanced anti-inflammatory,anticancer,and antioxidant activities.Moreover,surface-modified and targeted nanoparticles showed promise in increasing site-specific targeting and enhancing bioavailability of the encapsulated compounds.Nanoformulations present a promising strategy for overcoming the pharmacokinetic limitations of phytochemicals.Despite encouraging preclinical results,further studies are needed to address issues related to long-term safety,clinical efficacy,and regulatory approval for successful clinical translation. 展开更多
关键词 PHYTOCONSTITUENTS Nanoformulations Bioavailability enhancement NANOTECHNOLOGY Personalized medicine COSMECEUTICALS NUTRACEUTICALS
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Exosomes: Emerging implementation of nanotechnology for detecting and managing novel corona virus-SARS-CoV-2 被引量:2
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作者 Akhilesh Dubey Cynthia Lizzie Lobo +3 位作者 Ravi GS Amitha Shetty Srinivas Hebbar Sally AEl-Zahaby 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2022年第1期20-34,共15页
The spread of SARS-CoV-2 as an emerging novel coronavirus disease (COVID-19) had progressed as a worldwide pandemic since the end of 2019. COVID-19 affects firstly lungs tissues which are known for their very slow reg... The spread of SARS-CoV-2 as an emerging novel coronavirus disease (COVID-19) had progressed as a worldwide pandemic since the end of 2019. COVID-19 affects firstly lungs tissues which are known for their very slow regeneration. Afterwards, enormous cytokine stimulation occurs in the infected cells immediately after a lung infection which necessitates good management to save patients. Exosomes are extracellular vesicles of nanometric size released by reticulocytes on maturation and are known to mediate intercellular communications. The exosomal cargo serves as biomarkers in diagnosing various diseases;moreover, exosomes could be employed as nanocarriers in drug delivery systems. Exosomes look promising to combat the current pandemic since they contribute to the immune response against several viral pathogens. Many studies have proved the potential of using exosomes either as viral elements or host systems that acquire immune-stimulatory effects and could be used as a vaccine or drug delivery tool. It is essential to stop viral replication, prevent and reverse the massive storm of cytokine that worsens the infected patients’ situations for the management of COVID-19. The main benefits of exosomes could be;no cells will be introduced, no chance of mutation, lack of immunogenicity and the damaged genetic material that could negatively affect the recipient is avoided. Additionally, it was found that exosomes are static with no ability for in vivo reproduction. The current review article discusses the possibilities of using exosomes for detecting novel coronavirus and summarizes state of the art concerning the clinical trials initiated for examining the use of COVID-19 specific T cells derived exosomes and mesenchymal stem cells derived exosomes in managing COVID-19. 展开更多
关键词 EXOSOMES COVID-19 Specific T cell-derived exosomes Mesenchymal stem cells-derived EXOSOMES NANOTECHNOLOGY SARS-Co V-2
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Extraction of Carotenoids and Fatty Acids from Microalgae Using Supercritical Technology 被引量:1
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作者 Lourdes Casas Cardoso Casimiro Mantell Serrano +2 位作者 Miguel Rodríguez Rodríguez Enrique J. Martínez de la Ossa Luis M. Lubián 《American Journal of Analytical Chemistry》 2012年第12期877-883,共7页
The work described here is based on a comparative study of carotenoids and fatty acids extracted from Synechococcus sp. with (1) pure supercritical CO2, (2) CO2 with 5% (v/v) ethanol as cosolvent and (3) ultrasound-as... The work described here is based on a comparative study of carotenoids and fatty acids extracted from Synechococcus sp. with (1) pure supercritical CO2, (2) CO2 with 5% (v/v) ethanol as cosolvent and (3) ultrasound-assisted extraction using N, N-dimethylformamide (DMF). The effects of extraction conditions on supercritical CO2 extraction with and within cosolvent were analyzed at different temperatures (40℃, 50℃ and 60℃) and pressures (200, 300 and 400 bars). SFE with CO2 proved to be the most selective method for the extraction of β-carotene, but under these conditions the contents of zeaxanthin and fatty acids were only comparable to or lower than those obtained with techniques that use SFE cosolvent. The SFE technique with CO2 and ethanol simultaneously extracted β-carotene and zeaxanthin and not only increased the concentrations of fatty acids obtained, but also helped to remove fatty acids (palmitoleic and linolenic acid) that were not obtained with pure CO2. Comparison of the supercritical technology with the ultrasound-assisted extraction (UAE) shows that the former technique is the most appropriate due to the fact that ethanol is generally regarded as a safe solvent in comparison to DMF. 展开更多
关键词 Carotenoids FATTY ACIDS SYNECHOCOCCUS sp. SUPERCRITICAL Technology Ultrasound-Assisted EXTRACTION
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Comparison of ELISA and HPLC-MS methods for the determination of exenatide in biological and biotechnology-based formulation matrices 被引量:1
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作者 A.R. Pinho A. Fortuna +5 位作者 A. Falcao A.C. Santos R. Seia C. Estevens F. Veiga A.J. Ribeiro 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2019年第3期143-155,共13页
The development of biotechnology-based active pharmaceutical ingredients, such as GLP-1 analogs, brought changes in type 2 diabetes treatment options. For better therapeutic efficiency, these active pharmaceutical ing... The development of biotechnology-based active pharmaceutical ingredients, such as GLP-1 analogs, brought changes in type 2 diabetes treatment options. For better therapeutic efficiency, these active pharmaceutical ingredients require appropriate administration, without the development of adverse effects or toxicity. Therefore, it is required to develop several quantification methods for GLP-1 analogs products, in order to achieve the therapeutic goals, among which ELISA and HPLC arise. These methods are developed, optimized and validated in order to determine GLP-1 analogs, not only in final formulation of the active pharmaceutical ingredient, but also during preclinical and clinical trials assessment. This review highlights the role of ELISA and HPLC methods that have been used during the assessment for GLP-1 analogs, especially for exenatide. 展开更多
关键词 Type 2 diabetes EXENATIDE THERAPEUTIC drug monitoring ELISA HPLC
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Nanotechnology: Effective topical delivery systems
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作者 Tasana Pitaksuteepong 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2016年第1期16-17,共2页
Nanotechnology has received much interest nowadays. It isdefined as techniques, methods or processes to fabricate nanoscalestructures with size less than 100 nm. The deliveryof a compound via skin offers many advantag... Nanotechnology has received much interest nowadays. It isdefined as techniques, methods or processes to fabricate nanoscalestructures with size less than 100 nm. The deliveryof a compound via skin offers many advantages including beingpain-free, ease of administration, avoidance of hepatic firstpassmetabolism and low cost. However, the major barrier ofthis route is the stratum corneum, which is the outermostlayer of the epidermis. Thus effective nanodelivery systemsare essential and no wonder why these systems reveal significantroles in delivery of cosmetics, drugs and biologicalproducts via topical routes these days. There are a variety ofnanodelivery systems for topical route. However, this presentationcovers polymeric nanoparticles and amphiphilicassociationstructures, which are the systems of the author’sparticular interest. 展开更多
关键词 NANOTECHNOLOGY TOPICAL POLYMERIC nanoparticles Micelles MICROEMULSIONS LYOTROPIC liquid CRYSTAL
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Impact of Science and Technology on International Relations in the Digital Era
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作者 Alexey V.Biryukov 《Contemporary International Relations》 2015年第6期114-129,共16页
Assessing and analyzing the impact of science and technology on international relations is now a specific area for foreign policy analystsin the digital era. Progress in science and technology developing concurrently ... Assessing and analyzing the impact of science and technology on international relations is now a specific area for foreign policy analystsin the digital era. Progress in science and technology developing concurrently with the global revolution in information and the transition to a multipolar world have thrust upon international relations the imperative to establish a global technology alliance. This includes creation of a global technology fund, renovation of the global technology transfer, and the broadening of global cloud technology resource. 展开更多
关键词 国际关系 数字时代 科技进步 科学技术 外交政策 技术联盟 信息革命 技术转移
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Factors Influencing Attitude towards Technology Adoption among Permanent Food Production Park (PFPP) Program Participants in West Malaysia
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作者 Zulqarnain Norsida Man +2 位作者 Juwaidah Sharifuddin Muhammad Roslan Salim Hassan 《Journal of Agricultural Science and Technology(B)》 2020年第2期89-97,共9页
The study explores the factors influencing attitude towards agricultural technology adoption among Permanent Food Production Park(PFPP)program participants in West Malaysia and the factors that influence their attitud... The study explores the factors influencing attitude towards agricultural technology adoption among Permanent Food Production Park(PFPP)program participants in West Malaysia and the factors that influence their attitudes.The PFPP program is one of the programs introduced by the government of Malaysia with the objectives of increasing food production,as well as supporting local agriculture entrepreneurs.The study employed a cross-sectional study design and has been conducted in four West Malaysian states with a sample of size of 275 respondents.The results indicated that the respondents had a positive attitude towards technology adoption and factors such as knowledge and skill,benefit,education level,years of experience in agriculture and gross income had influenced their attitude. 展开更多
关键词 Agriculture technology adoption food production
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Analysis of the Economical, Ecological and Quality Advantages Consequent Resulting from Initiation of Technology Integrated in Metallurgy
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作者 Ewa Kubinska-Jabcon Wiktor Kubinski Mariusz Niekurzak 《Journal of Mechanics Engineering and Automation》 2015年第10期549-553,共5页
Metallurgical sector plays an important role in the economy of each country because steel products present essential raw material for basic industries. Changes in the sectors of iron, steel and non-ferrous metals and ... Metallurgical sector plays an important role in the economy of each country because steel products present essential raw material for basic industries. Changes in the sectors of iron, steel and non-ferrous metals and the current development of technology forces the steel mills increased productivity, reduce production costs while ensuring to obtain a product with the required properties and to improve the competitiveness of enterprises in the global market. Currently, the most popular in meeting these requirements, enjoys a method of integration which combines individual operations into one integrated whole. The use of modem, perfectly designed, fully automated design of mechanical, hydraulic and measurement allowed us to achieve an innovative line of production. This article presents the general characteristics of the steel industry and a description of the latest integrated technology currently used in foundries and rolling mills. It also presents examples of the use of integrated technologies in metallurgy and the effects of economic, environmental and quality resulting from their use on an industrial scale. 展开更多
关键词 Metallurgical sector integrated technology
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The Scientific Initiation in the Graduation Courses of UEMG's Faculty of Engineering: Disparities and Challenges
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作者 Filipe Mattos Goncalves Natalia Pereira da Silv +1 位作者 Junia Soares Alexandrino Telma Ellen Drumond Ferreira 《Journal of Mechanics Engineering and Automation》 2017年第2期101-106,共6页
The notoriety of the shortage of qualified professionals in the engineering segment to meet the existing projects and also the future ones is worrying the academic community. These challenges show how the lack of appr... The notoriety of the shortage of qualified professionals in the engineering segment to meet the existing projects and also the future ones is worrying the academic community. These challenges show how the lack of appropriate courses and low expenses with incentives to research and extension programs can affect the formation of the future engineer. Therefore, universities have the mission to develop teaching, research and extension, offering to the students new opportunities for diverse technical training, scientific and humanist formation. It is noted, however, that such activities in many engineering courses, especially scientific research, are not being prioritized by the universities. In light of this, the present paper aims to register measure and evaluate the participation of the students in scientific initiation in the four engineering courses of the Faculty of Engineering of the Minas Gerais State University. Sticking to the disparities presented by the four courses studied, in relation to the participation in research projects, the results showed a greater engagement of students of Environmental Engineering and Mining Engineering courses regarding the other engineering courses. In addition, a better divulgation and a greater involvement of teachers in projects were identified as the main recurring challenges to the access in scientific research by the students of this institution. 展开更多
关键词 CHALLENGES ENGINEERING scientific initiation university.
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Advances in coastal ocean boundary layer detection technology and equipment in China 被引量:1
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作者 Haitao Zheng Youwen Sun +13 位作者 Tao Luo Xueling Cheng Shiyong Shao Shouyin Zheng Bangyi Tao Bin Chen Qianguang Tu Kan Huang Bingbing Wang Mian Wang Xiaoquan Song Tianshu Zhang Yin Cheng Jianguo Liu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2023年第1期156-168,共13页
Accurate and comprehensive knowledge of the atmospheric environment and its evolution within the coastal ocean boundary layer are necessary for understanding the sources,chemical mechanisms,and transport processes of ... Accurate and comprehensive knowledge of the atmospheric environment and its evolution within the coastal ocean boundary layer are necessary for understanding the sources,chemical mechanisms,and transport processes of air pollution in land,sea,and atmosphere.We present an overview of coastal ocean boundary layer detection technology and equipment in China and summarize the progress and main achievements in recent years.China has developed a series of coastal ocean boundary layer detection technologies,including Light Detection and Ranging(LIDAR),turbulent exchange analyzer,air-sea flux analyzer,stereoscopic remote sensing of air pollutants,and oceanic aerosol detection equipment to address the technical bottleneck caused by harsh environmental conditions in coastal ocean regions.Advances in these technologies and equipment have provided scientific assistance for addressing air pollution issues and understanding land-sea-atmosphere interactions over coastal ocean regions in China.In the future,routine atmospheric observations should cover the coastal ocean boundary layer of China. 展开更多
关键词 Atmospheric pollution Coastal ocean Atmospheric monitoring Environmental instrument
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Hydrogen Energy Storage System:Review on Recent Progress 被引量:1
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作者 MilleniumWong Hadi Nabipour Afrouzi 《Energy Engineering》 EI 2025年第1期1-39,共39页
A hydrogen energy storage system(HESS)is one of the many risingmodern green innovations,using excess energy to generate hydrogen and storing it for various purposes.With that,there have been many discussions about com... A hydrogen energy storage system(HESS)is one of the many risingmodern green innovations,using excess energy to generate hydrogen and storing it for various purposes.With that,there have been many discussions about commercializing HESS and improving it further.However,the design and sizing process can be overwhelming to comprehend with various sources to examine,and understanding optimal design methodologies is crucial to optimize a HESS design.With that,this review aims to collect and analyse a wide range of HESS studies to summarise recent studies.Two different collections of studies are studied,one was sourced by the main author for preliminary readings,and another was obtained via VOSViewer.The findings from the Web of Science platform were also examined for amore comprehensive understanding.Major findings include the People’sRepublic of China has been active in HESS research,as most works and active organizations originate from this country.HESS has been mainly researched to support power generation and balance load demands,with financial analysis being the common scope of analysis.MATLAB is a common tool used for HESS design,modelling,and optimization as it can handle complex calculations.Artificial neural network(ANN)has the potential to be used to model the HESS,but additional review is required as a formof future work.From a commercialization perspective,pressurized hydrogen tanks are ideal for hydrogen storage in a HESS,but other methods can be considered after additional research and development.From this review,it can be implied that modelling works will be the way forward for HESS research,but extensive collaborations and additional review are needed.Overall,this review summarized various takeaways that future research works on HESS can use. 展开更多
关键词 Hydrogen energy storage system VOSViewer DESIGN REVIEW SIZING
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Machine Learning Techniques in Predicting Hot Deformation Behavior of Metallic Materials
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作者 Petr Opela Josef Walek Jaromír Kopecek 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期713-732,共20页
In engineering practice,it is often necessary to determine functional relationships between dependent and independent variables.These relationships can be highly nonlinear,and classical regression approaches cannot al... In engineering practice,it is often necessary to determine functional relationships between dependent and independent variables.These relationships can be highly nonlinear,and classical regression approaches cannot always provide sufficiently reliable solutions.Nevertheless,Machine Learning(ML)techniques,which offer advanced regression tools to address complicated engineering issues,have been developed and widely explored.This study investigates the selected ML techniques to evaluate their suitability for application in the hot deformation behavior of metallic materials.The ML-based regression methods of Artificial Neural Networks(ANNs),Support Vector Machine(SVM),Decision Tree Regression(DTR),and Gaussian Process Regression(GPR)are applied to mathematically describe hot flow stress curve datasets acquired experimentally for a medium-carbon steel.Although the GPR method has not been used for such a regression task before,the results showed that its performance is the most favorable and practically unrivaled;neither the ANN method nor the other studied ML techniques provide such precise results of the solved regression analysis. 展开更多
关键词 Machine learning Gaussian process regression artificial neural networks support vector machine hot deformation behavior
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YOLOCSP-PEST for Crops Pest Localization and Classification 被引量:1
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作者 Farooq Ali Huma Qayyum +2 位作者 Kashif Saleem Iftikhar Ahmad Muhammad Javed Iqbal 《Computers, Materials & Continua》 2025年第2期2373-2388,共16页
Preservation of the crops depends on early and accurate detection of pests on crops as they cause several diseases decreasing crop production and quality. Several deep-learning techniques have been applied to overcome... Preservation of the crops depends on early and accurate detection of pests on crops as they cause several diseases decreasing crop production and quality. Several deep-learning techniques have been applied to overcome the issue of pest detection on crops. We have developed the YOLOCSP-PEST model for Pest localization and classification. With the Cross Stage Partial Network (CSPNET) backbone, the proposed model is a modified version of You Only Look Once Version 7 (YOLOv7) that is intended primarily for pest localization and classification. Our proposed model gives exceptionally good results under conditions that are very challenging for any other comparable models especially conditions where we have issues with the luminance and the orientation of the images. It helps farmers working out on their crops in distant areas to determine any infestation quickly and accurately on their crops which helps in the quality and quantity of the production yield. The model has been trained and tested on 2 datasets namely the IP102 data set and a local crop data set on both of which it has shown exceptional results. It gave us a mean average precision (mAP) of 88.40% along with a precision of 85.55% and a recall of 84.25% on the IP102 dataset meanwhile giving a mAP of 97.18% on the local data set along with a recall of 94.88% and a precision of 97.50%. These findings demonstrate that the proposed model is very effective in detecting real-life scenarios and can help in the production of crops improving the yield quality and quantity at the same time. 展开更多
关键词 Deep learning classification of pests YOLOCSP-PEST pest detection
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Based on non-targeted metabolomics for differential components screening of Rosae Chinensis Flos and Rosae Rugosae Flos and their quality evaluation
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作者 Xu Liang Ni-Hui Zhang +4 位作者 Zhi-Lai Zhan Guang-Lu Chang Yan Gao Xia Li Wen-Yuan Gao 《Traditional Medicine Research》 2025年第2期1-15,共15页
Background:Rosa chinensis Jacq.and Rosa rugosa Thunb.are not only of ornamental value,but also edible flowers and the flower buds have been listed in the Chinese Pharmacopoeia as traditional medicines.The two plants h... Background:Rosa chinensis Jacq.and Rosa rugosa Thunb.are not only of ornamental value,but also edible flowers and the flower buds have been listed in the Chinese Pharmacopoeia as traditional medicines.The two plants have some differences in efficacy,but the flower buds are easily confused for similar traits.In addition,large-scale cultivation of ornamental rose flowers may lead to a decrease in the effective components of medicinal roses.Therefore,it is necessary to study the chemical composition and make quality evaluation of Rosae Chinensis Flos(Yueji)and Rosae Rugosae Flos(Meigui).Methods:In this study,40 batches of samples including Meigui and Yueji from different regions in China were collected to establish high-performance liquid chromatography fingerprints.Then,the fingerprints data was analyzed using principal component analysis,hierarchical cluster analysis,and partial least squares discriminant analysis analysis chemometrics to obtain information on intergroup differences,and non-targeted metabolomic techniques were applied to identify and compare chemical compositions of samples which were chosen from groups with large differences.Differential compounds were screened by orthogonal partial least-squares discriminant analysis and S-plot,and finally multi-component quantification was performed to comprehensively evaluate the quality of Yueji and Meigui.Results:The similarity between the fingerprints of 40 batches roses and the reference print R was 0.73 to 0.93,indicating that there were similarities and differences between the samples.Through principal component analysis and hierarchical cluster analysis of fingerprints data,the samples from different origins and varieties were intuitively divided into four groups.Partial least-squares discriminant analysis analysis showed that Meigui and Yueji cluster into two categories and the model was reliable.A total of 89 compounds were identified by high resolution mass spectrometry,mainly were flavonoids and flavonoid glycosides,as well as phenolic acids.Eight differential components were screened out by orthogonal partial least-squares discriminant analysis and S-plot analysis.Quantitative analyses of the eight compounds,including gallic acid,ellagic acid,hyperoside,isoquercitrin,etc.,showed that Yueji was generally richer in phenolic acids and flavonoids than Meigui,and the quality of Yueji from Shandong and Hebei was better.It is worth noting that Xinjiang rose is rich in various components,which is worth focusing on more in-depth research.Conclusion:In this study,the fingerprints of Meigui and Yueji were established.The chemical components information of roses was further improved based on non-targeted metabolomics and mass spectrometry technology.At the same time,eight differential components of Meigui and Yueji were screened out and quantitatively analyzed.The research results provided a scientific basis for the quality control and rational development and utilization of Rosae Chinensis Flos and Rosae Rugosae Flos,and also laid a foundation for the study of their pharmacodynamic material basis. 展开更多
关键词 Rosa chinensis Jacq. Rosa rugosa Thunb. metabolomics CHEMOMETRICS multiple component quantification quality evaluation
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The coating application for enhanced adhesion between GFRP composites and cataphoresis-coated(KTL)steel–part 1:mechanical properties
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作者 Celalettin Baykara Enes Bilgin 《Railway Sciences》 2025年第4期425-449,共25页
Purpose–This research aims to investigate how the adhesion performance of GFRP composite components,commonly used in railway vehicles,is affected when bonded to cataphoresis coated steel substrate surfaces.Design/met... Purpose–This research aims to investigate how the adhesion performance of GFRP composite components,commonly used in railway vehicles,is affected when bonded to cataphoresis coated steel substrate surfaces.Design/methodology/approach–In this context,the aim was to determine the optimal adhesion parameters for bonding GFRP samples with natural and primed surfaces to steel samples with cataphoresis coatings.Then,single-lap joint samples with different bond thicknesses of 1 mm,2 mm and 3 mm were prepared.Finally,tensile tests were performed on the samples.Findings–The results showed that GFRP specimens with natural surfaces,characterised by the highest surface roughness,exhibited the lowest bond strength.But,the highest bonding performance was achieved in specimens where primed GFRP was bonded to cataphoresis coated steel,especially with a bond thickness of 1 mm,and achieving a yield strength of 20 MPa.This situation explains the characteristic difference between surface roughness and chemical coating,which are two essential pre-treatments in adhesive bonding.While surface roughness provides mechanical interlocking,excessive roughness can hinder the adhesive’s wetting ability,causing it to remain suspended on the surface as described in the Cassie–Baxter theorem.In contrast,it has been observed that,despite low surface roughness,chemical coatings enhance the bonding between primer paint and adhesive molecules,and–as stated in the Wenzel theorem–improve the surface wettability.Originality/value–As a preliminary preparation in the adhesive method,primer paint is applied to steel surfaces and GFRP material surfaces in classical industrial applications.In this research,the application of the catapheresis process to the steel substrate instead of primer paint and the bonding of primer-painted GFRP materials to this surface make a unique contribution to the research. 展开更多
关键词 Adhesion bonding Surface coating Cataphoresis coating(KTL) Primer painting Wenzel equation Cassey-Baxter equation
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The coating application for enhanced adhesion between GFRP composites and cataphoresis-coated(KTL)steel–part 2:surface properties
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作者 Celalettin Baykara Enes Bilgin 《Railway Sciences》 2025年第5期565-579,共15页
Purpose–This study examines the effect of increased surface energy on adhesion strength.Surface modifications were made using chemical coating methods such as primer paint(primer)and cataphoresis(KTL,Kathodische Tauc... Purpose–This study examines the effect of increased surface energy on adhesion strength.Surface modifications were made using chemical coating methods such as primer paint(primer)and cataphoresis(KTL,Kathodische Tauchlackierung).The wetting behaviour of adhesive on these surfaces and the resulting contact angles were analysed to evaluate bonding effectiveness.Design/methodology/approach–Primer paint was applied to glass fibre reinforced plastic(GFRP)materials and cataphoresis coating was applied to steel.Contact angles of the coated surfaces were measured and compared to those of the uncoated(natural)surfaces.Findings–Results showed that applying primer to GFRP and KTL to steel increased their surface energy compared to untreated surfaces.A decrease in contact angle correlated with improved wetting,suggesting enhanced adhesion potential.Originality/value–While the effects of surface coatings on adhesion have been studied,there is limited research specifically on the adhesion-enhancing potential of KTL coatings.Typically used for corrosion resistance,KTL is shown here to also improve adhesion.The novelty lies in experimentally demonstrating KTL’s dual role as both a protective and adhesion-enhancing layer. 展开更多
关键词 Surface tension Surface energy Contact angle WETTABILITY Adhesive bonding
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Investigation of mechanical strength and deformation properties of Y25 bogie suspension systems by finite element analysis
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作者 Celalettin Baykara 《Railway Sciences》 2025年第6期685-710,共26页
Purpose–This paper aims to offer a novel viewpoint for improving performance and reliability by developing and optimizing suspension components in a Y25 bogie through material optimization based on wheel–rail intera... Purpose–This paper aims to offer a novel viewpoint for improving performance and reliability by developing and optimizing suspension components in a Y25 bogie through material optimization based on wheel–rail interactions under variable load and track conditions.Design/methodology/approach–The suspension system,a critical component ensuring adaptation to road and load conditions in all vehicle types,is especially vital in heavy freight and passenger trains.In this context,the suspension set of the Y25 bogie–commonly used in T€urkiye and Europe–was modelled using CATIAV5,and stress analyses have been performed by way of ANSYS using the finite element analysis(FEA)method.E300-520-M cast steel was selected for the bogie frame,while two different spring steels,61SiCr7 and 51CrV4,were considered for the suspension springs.The modeled system was subjected to numerical analysis under loading conditions.The resulting stresses and displacements were compared with the mechanical properties of the selected materials to validate the design.Findings–The results demonstrate that the mechanical strength and deformation characteristics of the suspension components vary according to the applied external loads.The stress and displacement responses of the system were found to be within the allowable limits of the selected materials,confirming the structural integrity and reliability of the design.The suspension set is deemed suitable for the prescribed material and environmental conditions,suggesting potential for practical application in real-world rail systems.Originality/value–This research contributes to the design and optimization of bogie suspension systems using advanced CAD/CAE tools.It thinks that the material selection and numerical validation approach presented here can guide future designs in heavy load rail applications and potentially improve both safety and performance. 展开更多
关键词 Finite element analysis Y25 railway bogie Suspension system Railway vehicles Wheel-rail interaction
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Citespace-based Analysis of the Importance of Species Surveys in Restorative Environment Studies
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作者 JING Zirui LI Tongyu WANG Xiaobo 《Journal of Landscape Research》 2025年第2期37-41,46,共6页
[Objective]Mental health is the essence of physical health,human beings pay more and more attention to the study of mental health recovery and after many studies,it is clear that the restorative environment has an imp... [Objective]Mental health is the essence of physical health,human beings pay more and more attention to the study of mental health recovery and after many studies,it is clear that the restorative environment has an important and positive significance for their mental recovery,and species as an important part of the environment since the natural environment has been used as an essential part of the research environment,based on the conditions of such a social reality,this paper analyzed the articles on species surveys in the last 30 years,used the data to reflect the importance of species survey,and the research hotspot of restorative environment.[Methods]The study analyzed the data in articles about species survey in CNKI database from 1994 to 2024 through Citespace visualization,and analyzed the data through the number of articles issued between years,keyword co-occurrence and other aspects,so as to give data support for the research of restorative environment.[Results]In the past 30 years,the number of articles published on species survey has increased year by year,and species survey is at the forefront of research hotspots.Clustering and timeline analysis results of insects,birds,diversity has become more important.[Conclusions]From the 621 articles,the following aspects could be concluded:(1)The importance of restorative environments research and the vast exchanges among scholars have been reflected and more research hotspots have been explored in this field;(2)For the research direction of restorative environments and this paper,the research hotspots were in line with the in-depth exploration of species diversity,which was not only in the field of species,but also in the field of health and the environment,and there were also investigations of the links;(3)The interdependence between species diversity and restorative environments was high,further research on restorative environments largely depended on the study of species surveys. 展开更多
关键词 Species survey BIRD Restorative environment Citespace Data analysis
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Finite Element Modeling of Thermo-Viscoelastoplastic Behavior of Dievar Alloy under Hot Rotary Swaging
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作者 Josef Izák Marek Benc Petr Opěla 《Computer Modeling in Engineering & Sciences》 2025年第3期3115-3133,共19页
The paper deals with the FEM(Finite Element Method)simulation of rotary swaging of Dievar alloy produced by additive manufacturing technology Selective Laser Melting and conventional process.Swaging was performed at a... The paper deals with the FEM(Finite Element Method)simulation of rotary swaging of Dievar alloy produced by additive manufacturing technology Selective Laser Melting and conventional process.Swaging was performed at a temperature of 900℃.True flow stress-strain curves were determined for 600℃–900℃and used to construct a Hensel-Spittel model for FEM simulation.The process parameters,i.e.,stress,temperature,imposed strain,and force,were investigation during the rotary swaging process.Firstly,the stresses induced during rotary swaging and the resistance of the material to deformation were investigated.The amount and distribution of imposed strain in the cross-section can serve as a valuable indicator of the reduction in porosity and the texture evolution of the material.The simulation revealed the force required to swag the Dievar alloy.It also showed the evolution of temperature,which is important for phase transformation during solidification.Furthermore,microstructure evolutionwas observed before and then after rotary swaging.Dievar alloy is a critical material in the manufacture of dies for high-pressure die casting,forging tools,and other equipment subjected to high temperatures and mechanical loads.Understanding its viscoelastoplastic behavior under rotary swaging conditions is essential to optimize its performance in these demanding industrial applications. 展开更多
关键词 FEM rotary swaging SLM selective laser melting dievar ingot casting hot work tool steel additive manufacturing
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Enhancing Heart Sound Classification with Iterative Clustering and Silhouette Analysis:An Effective Preprocessing Selective Method to Diagnose Rare and Difficult Cardiovascular Cases
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作者 Sami Alrabie Ahmed Barnawi 《Computer Modeling in Engineering & Sciences》 2025年第8期2481-2519,共39页
In the effort to enhance cardiovascular diagnostics,deep learning-based heart sound classification presents a promising solution.This research introduces a novel preprocessing method:iterative k-means clustering combi... In the effort to enhance cardiovascular diagnostics,deep learning-based heart sound classification presents a promising solution.This research introduces a novel preprocessing method:iterative k-means clustering combined with silhouette score analysis,aimed at downsampling.This approach ensures optimal cluster formation and improves data quality for deep learning models.The process involves applying k-means clustering to the dataset,calculating the average silhouette score for each cluster,and selecting the clusterwith the highest score.We evaluated this method using 10-fold cross-validation across various transfer learningmodels fromdifferent families and architectures.The evaluation was conducted on four datasets:a binary dataset,an augmented binary dataset,amulticlass dataset,and an augmentedmulticlass dataset.All datasets were derived from the Heart Wave heart sounds dataset,a novelmulticlass dataset introduced by our research group.To increase dataset sizes and improve model training,data augmentation was performed using heartbeat cycle segmentation.Our findings highlight the significant impact of the proposed preprocessing approach on the HeartWave datasets.Across all datasets,model performance improved notably with the application of our method.In augmented multiclass classification,the MobileNetV2 model showed an average weighted F1-score improvement of 27.10%.In binary classification,ResNet50 demonstrated an average accuracy improvement of 8.70%,reaching 92.40%compared to its baseline performance.These results underscore the effectiveness of clustering with silhouette score analysis as a preprocessing step,significantly enhancing model accuracy and robustness.They also emphasize the critical role of preprocessing in addressing class imbalance and advancing precision medicine in cardiovascular diagnostics. 展开更多
关键词 Heart sound MURMURS cardiovascular diseases(CVDs) transfer learning convolutional neural network(CNN) deep learning K-means silhouette analysis
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