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A novel finite element formulation for static bending analysis of functionally graded porous sandwich plates

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Frontiers of Structural and Civil Engineering 2022年第12期16卷 1599-1620页

作者： Van Chinh NGUYEN Trung Thanh TRAN Trung NGUYEN-THOI Quoc-Hoa PHAM faculty of Mechanical Engineering Le Quy Don Technical UniversityHanoiVietnam Laboratory for Applied and Industrial Mathematics Institute for Computational Science and Artificial IntelligenceVan Lang UniversityHo Chi Minh CityVietnam faculty of Mechanical-Electrical and Computer Engineering Van Lang UniversityHo Chi Minh CityVietnam faculty of Engineering and Technology Nguyen Tat Thanh UniversityHo Chi Minh CityVietnam

This article aims to propose a finite element formulation based on Quasi-3D theory for the static bending analysis of functionally graded porous(FGP)sandwich plates.The FGP sandwich plates consist of three layers including the bottom skin of homogeneous metal,the top skin of fully ceramic and the FGP core layer with uneven porosity distribution.A quadrilateral(Q4)element with nine degrees of freedom(DOFs)per node is derived and employed in analyzing the static bending response of the plate under uniform and/or sinusoidally distributed loads.The accuracy of the present finite element formulation is verified by comparing the obtained numerical results with the published results in the literature.Then,some numerical examples are performed to examine the effects of the parameters including power-law index k and porosity coefficient on the static bending response of rectangular FGP sandwich plates.In addition,a problem with a complicated L-shape model is conducted to illustrate the superiority of the proposed finite element method.

关键词： sandwich plates functionally graded porous static bending Quasi-3D theory Q4 element

S-Nitroso-N-acetyl-L-cysteine ethyl ester(SNACET) and N-acetyl-L-cysteine ethyl ester(NACET)–Cysteine-based drug candidates with unique pharmacological profiles for oral use as NO, H_2S and GSH suppliers and as antioxidants: Results and overview

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Journal of Pharmaceutical Analysis 2018年第1期8卷 1-9页

作者： Dimitrios Tsikas Kathrin S.Schwedhelm Andrzej Surdacki Daniela Giustarini Ranieri Rossi Lea Kukoc-Modun George Kedia Stefan ückert Institute of Toxicology Core Unit Proteomics Hannover Medical School Second Department of Cardiology Jagiellonian University Medical College Department of Medicine Surgery and Neuroscience University of Siena Department of Life Sciences Laboratory of Pharmacology and Toxicology University of Siena Department of Analytical Chemistry Faculty of Chemistry and Technology University of Split Department of Urology and Urological Oncology Hannover Medical School

S-Nitrosothiols or thionitrites with the general formula RSNO are formally composed of the nitrosyl cation(NOt) and a thiolate(RSà), the base of the corresponding acids RSH. The smallest S-nitrosothiol is HSNO and derives from hydrogen sulfide(HSH, H_2S). The most common physiological S-nitrosothiols are derived from the amino acid L-cysteine(Cys SH). Thus, the simplest S-nitrosothiol is S-nitroso-L-cysteine(Cys SNO). Cys SNO is a spontaneous potent donor of nitric oxide(NO) which activates soluble guanylyl cyclase to form cyclic guanosine monophosphate(c GMP). This activation is associated with multiple biological actions that include relaxation of smooth muscle cells and inhibition of platelet aggregation.Like NO, Cys SNO is a short-lived species and occurs physiologically at concentrations around 1 n M in human blood. Cys SNO can be formed from Cys SH and higher oxides of NO including nitrous acid(HONO)and its anhydride(N_2O_3). The most characteristic feature of RSNO is the S-transnitrosation reaction by which the NOtgroup is reversibly transferred to another thiolate. By this way numerous RSNO can be formed such as the low-molecular-mass S-nitroso-N-acetyl-L-cysteine(SNAC) and S-nitroso-glutathione(GSNO), and the high-molecular-mass S-nitrosol-L-cysteine hemoglobin(Hb Cys SNO) present in erythrocytes and S-nitrosol-L-cysteine albumin(Alb Cys SNO) present in plasma at concentrations of the order of 200 n M. All above mentioned RSNO exert NO-related biological activity, but they must be administered intravenously. This important drawback can be overcome by lipophilic charge-free RSNO.Thus, we prepared the ethyl ester of SNAC, the S-nitroso-N-acetyl-L-cysteine ethyl ester(SNACET), from synthetic N-acetyl-L-cysteine ethyl ester(NACET). Both NACET and SNACET have improved pharmacological features over N-acetyl-L-cysteine(NAC) and S-nitroso-N-acetyl-L-cysteine(SNAC), respectively,including higher oral bioavailability. SNACET exerts NO-related activities which can be utilized in the urogenital tract and in the card

关键词： CGMP Nitric oxide S-Nitrosothiols Oxidative stress Pharmaceuticals

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组织文化对促进护士专业认证的作用

International Journal of Nursing Sciences 2023年第2期10卷 189-198页

作者： Holly Wei Lisa MHaddad Tricia A.Nwokocha Margaret Powers Aaron Wei Quinton Carroll Nancy Ballard East Tennessee State University College of Nursing Johnson CityTNUSA Nursing Educator core faculty Clinical Practice and Professional Development ServicePalo AltoCAUSA University of Louisville LouisvilleKYUSA University of North Carolina at Chapel Hill NCUSA Kennesaw State University Wellstar School of Nursing KennesawGAUSA

目的护理专业认证验证了护士在疾病管理、教育或领导能力方面掌握的专业知识高于入门级教育和许可.护理专业认证与患者护理质量直接相关.然而,护士的专业认证率仍然较低.本研究旨在了解护士对能够促进或阻碍专业认证的看法,以促进护士... 详细信息

目的护理专业认证验证了护士在疾病管理、教育或领导能力方面掌握的专业知识高于入门级教育和许可.护理专业认证与患者护理质量直接相关.然而,护士的专业认证率仍然较低.本研究旨在了解护士对能够促进或阻碍专业认证的看法,以促进护士获得专业认证的愿望和能力.方法 2022年5-9月,基于1项在美国进行的大型调查研究的嵌套样本进行质性研究.在同意接受访谈的护士中,使用目的抽样方法来实现样本的多样性,例如护士的工作年限、种族和认证状态.信息达到饱和用于确定样本量.通过虚拟面对面深入访谈收集资料.编码过程基于Colaizzi的资料分析方法进行.结果 20名护士参与了此项研究.共呈现5个主题,与促进护士专业认证的组织文化和策略相关,包括:共享资源,培养主人翁文化和归属感,指导和榜样,认可护士的努力和成就,以及培养意义感和追求目标及提供支持.结论组织文化和领导力在促进持续学习环境方面发挥着重要作用.发展促进护士专业认证的组织文化非常必要.这项研究明确了组织文化是支持护士获取认证的重要领域.需要进行更多研究来评估可能影响护理专业初始和持续认证水平的干预措施,尤其是在新型冠状病毒疫情之后.

关键词：认证促进因素和障碍领导力护士组织文化

In vitro anti-leishmanial activity of methanolic extracts of Calendula officinalis flowers, Datura stramonium seeds, and Salvia officinalis leaves

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Chinese Journal of Natural Medicines 2014年第6期12卷 423-427页

作者： Banafsheh Nikmehr Habib Ghaznavi Amir Rahbar Samira Sadr Saeed Mehrzadi Department of Anatomy Tehran University of Medical Sciences Tehran Iran Cellular and Molecular Research Center Zahedan University of Medical Sciences Zahedan Iran Department of Pharmacology School of Medicine Iran University of Medical Sciences Tehran Iran Department of Pathobiology Veterinary Faculty Shahid Chamran University Ahwaz Iran faculty of Veterinary Medicine University of Tehran Tehran Iran core Facilities Iran University of Medical Sciences Tehran Iran

AIM: The anti-leishmanial activity of methanolic extracts of Calendula officinalis flowers, Datura stramonium seeds, and Salvia officinalis leaves against extracellular(promastigote) and intracellular(amastigote) forms of Leishmania major were evaluated in this study. METHOD: In the first stage, promastigote forms of L. major, were treated with different doses of the plant extracts in a 96-well tissue-culture microplate and IC50 values for each extract were measured with colorimetric MTT assay. In the second stage, macrophage cells were infected with L. major promastigotes. Infected macrophages were treated with plant extracts. Then the macrophages were stained with Gimsa and the number of infected macrophages and amastigotes were counted with a light microscope. RESULTS: The results indicated that the plant extracts inhibited the growth of promastigotes and amastigotes of L. major. Inhibitory concentrations(IC50) for promastigote assay were 108.19, 155.15, and 184.32 μg·mL-1 for C. officinalis flowers, D. stramonium seeds and S. officinalis, respectively. The extracts also reduced the number of amastigotes in macrophage cells from 264 for control group to 88, 97, and 102 for test groups. Although the anti-leishmanial activity of the extracts were not comparable with the standard drug, miltefosine; but they showed significant efficiency in reducing the number of amastigotes in macrophages, in comparison with the control group(P < 0.001). These plant extracts had lower toxicity compared with miltefosine. CONCLUSION: This study demonstrates the potential efficacy of the methanolic extracts of C. officinalis flowers, D. stramonium seeds, and S. officinalis leaves to control of cutaneous leishmaniasis.

关键词： Leishmania major Promastigote Amastigote Calendula officinalis Datura stramonium Salvia officinalis

Variation in mantle lithology and composition beneath the Ngao Bilta volcano,Adamawa Massif,Cameroon volcanic line,West-central Africa

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Geoscience Frontiers 2020年第2期11卷 665-677页

作者： Robert Temdjim Merlin Patrick Njombie Wagsong Arnold Julien Nzakou Tsepeng Stephen Foley Department of Earth Sciences Faculty of SciencesUniversity of Yaounde IP.O.Box.812 YaoundeCameroon Department of Earth and Planetary Sciences and ARC Centre of Excellence for core to Crust Fluid Systems Macquarie UniversityNorth RydeNSW2109Australia

Mantle peridotites entrained as xenoliths in the lavas of Ngao Bilta in the eastern branch of the continental Cameroon Line were examined to constrain mantle processes and the origin and nature of melts that have modified the upper mantle beneath the Cameroon Line.The xenoliths consist mainly of lherzolite with subordinate harzburgite and dunite.They commonly contain olivine,orthopyroxene,clinopyroxene and spinel although the dunite is spinel-free.Amphibole is an essential constituent in the lherzolites.Mineral chemistry differs between the three types of peridotite:olivines have usual mantle-like Mg#of around 90 in lherzolites,but follow a trend of decreasing Mg#(to 82)and NiO(to 0.06 wt.%)that is continuous in the dunites.Lherzolites also contain orthopyroxenes and/or clinopyroxenes with low-Mg#,indicating a reaction that removes Opx and introduces Cpx,olivine,amphibole and spinel.This is attributed to reaction with a silica-undersaturated silicate melt such as nephelinite or basanite,which originated as a low-degree melt from a depleted source as indicated by low Al2O3 and Na2O in Cpx and high Na2O/K2O in amphibole.Thermobarometric estimates place the xenoliths at pressures of 11–15 kbar(35–50 km)and temperatures of 863–957C,along a dynamic rift geotherm and shallower than the region where carbonate melts may occur.The melt/rock reactions exhibited by the Ngao Bilta xenoliths are consistent with their peripheral position in the eastern branch of the Cameroon Volcanic Line in an area of thinned crust and lithosphere beneath the Adamawa Uplift.

关键词： Cameroon volcanic line Adamawa volcanic massif Peridotite xenoliths Partial melting Melt-rock reactions

Hybrid Global Optimization Algorithm for Feature Selection

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Computers, Materials & Continua 2023年第1期74卷 2021-2037页

作者： Ahmad Taher Azar Zafar Iqbal Khan Syed Umar Amin Khaled M.Fouad faculty of Computers and Artificial Intelligence Benha UniversityBenha13511Egypt College of Computer and Information Sciences Prince Sultan UniversityRiyadh11586Saudi Arabia faculty of Information Technology and Computer Science Nile UniversitySheikh ZaidEgypt

This paper proposes Parallelized Linear Time-Variant Acceleration Coefficients and Inertial Weight of Particle Swarm Optimization algorithm(PLTVACIW-PSO).Its designed has introduced the benefits of Parallel computing into the combined power of TVAC(Time-Variant Acceleration Coefficients)and IW(Inertial Weight).Proposed algorithm has been tested against linear,non-linear,traditional,andmultiswarmbased optimization algorithms.An experimental study is performed in two stages to assess the proposed PLTVACIW-PSO.Phase I uses 12 recognized Standard Benchmarks methods to evaluate the comparative performance of the proposed PLTVACIWPSO vs.IW based Particle Swarm Optimization(PSO)algorithms,TVAC based PSO algorithms,traditional PSO,Genetic algorithms(GA),Differential evolution(DE),and,finally,Flower Pollination(FP)algorithms.In phase II,the proposed PLTVACIW-PSO uses the same 12 known Benchmark functions to test its performance against the BAT(BA)and Multi-Swarm BAT algorithms.In phase III,the proposed PLTVACIW-PSO is employed to augment the feature selection problem formedical datasets.This experimental study shows that the planned PLTVACIW-PSO outpaces the performances of other comparable algorithms.Outcomes from the experiments shows that the PLTVACIW-PSO is capable of outlining a feature subset that is capable of enhancing the classification efficiency and gives the minimal subset of the core features.

关键词： Particle swarm optimization(PSO) time-variant acceleration coefficients(TVAC) genetic algorithms differential evolution feature selection medical data

Smart tailoring of molecular catalysts:Mounting approach to oxygen reduction reaction

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Journal of Materials Science & Technology 2024年第1期168卷 169-184页

作者： Anuj Kumar Mohd Ubaidullah Guoxin Zhang Jasvinder Kaur Saira Ajmal Mudassir Hasan Krishna Kumar Yadav Hafiz M.Adeel Sharif Ram K.Gupta Ghulam Yasin Nano-Technology Research Laboratory Department of ChemistryGLA UniversityMathuraUttar Pradesh 281406India Department of Chemistry College of ScienceKing Saud UniversityRiyadh 11451Saudi Arabia Department of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdaoShandong 266590China Institute for Advanced Study Shenzhen UniversityShenzhenGuangdong 518060China Department of Chemistry Kansas Polymer Research CenterPittsburg State UniversityPittsburgKS 66762United States faculty of Science and Technology Madhyanchal Professional UniversityRatibadBhopal 462044India Environmental and Atmospheric Sciences Research Group Scientific Research CenterAl-Ayen UniversityThi-QarNasiriyah 64001Iraq Department of Chemical Engineering King Khalid University Saudi Arabia Department of Chemistry School of SciencesIFTM UniversityMoradabadUttar Pradesh 244102India Research Center for Eco-Environmental Engineering Dongguan University of TechnologyDongguan 523808China School of Environment and Civil Engineering Dongguan University of TechnologyDongguanGuangdong 523808China

Efficient electrocatalytic rupture of energy-rich molecules(H_(2)and O_(2))is a green approach for gener-ating clean energy for modern societies.In this context,porphyry-type molecular electrocatalysts act intelligently toward oxygen reduction reaction(ORR),a fundamental process in fuel cells,due to their redox-rich chemistry,which involves core metal ions and macrocyclic ligands.The concerned scientific community has tried many times to correlate the ORR intermediates with their formation kinetics and simplify the associated multi H+/e-stages during the ORR process,constructing several volcano plots be-tween catalytic Tafel data,turnover frequencies,and overpotentials for many electrocatalysts.Despite the fact that many review articles on molecular electrocatalysts for ORR have been published,understanding the strategic implications and molecular catalyst intelligence towards homogenous ORR has been poorly explored.This review examined the relationships between volcano plots of current vs.thermodynamic parameters and the Sabatier principle in order to explain the intelligence of molecular electrocatalysts and approaches for their creation,as well as the difficulties and potential prospects of molecular electro-catalysts.These facts distinguish this review from previously published articles and will pique the scien-tific community’s interest in avoiding trial-and-error procedures for catalyst creation while also allowing for more exact evaluations of the molecular catalyst’s performance.

关键词： Electrocatalysis Molecular catalysts Oxygen reduction reaction Sabatier principle

Editorial board publication strategy and acceptance rates in Turkish national journals

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Journal of Data and Information Science 2023年第4期8卷 49-83页

作者： Lokman Tutuncu faculty of Economics and Administrative Sciences Zonguldak Bülent Ecevit UniversityZonguldakTurkey

Purpose: This study takes advantage of newly released journal metrics to investigate whether local journals with more qualified boards have lower acceptance rates, based on data from 219 Turkish national journals and 2,367 editorial board members.Design/methodology/approach: This study argues that journal editors can signal their scholarly quality by publishing in reputable journals. Conversely, editors publishing inside articles in affiliated national journals would send negative signals. The research predicts that high(low) quality editorial boards will conduct more(less) selective evaluation and their journals will have lower(higher) acceptance rates. Based on the publication strategy of editors, four measures of board quality are defined: Number of board inside publications per editor(INSIDER), number of board Social Sciences Citation Index publications per editor(SSCI), inside-to-SSCI article ratio(ISRA), and board citation per editor(CITATION). Predictions are tested by correlation and regression analysis.Findings: Low-quality board proxies(INSIDER, ISRA) are positively, and high-quality board proxies(SSCI, CITATION) are negatively associated with acceptance rates. Further, we find that receiving a larger number of submissions, greater women representation on boards, and Web of Science and Scopus(WOSS) coverage are associated with lower acceptance rates. Acceptance rates for journals range from 12% to 91%, with an average of 54% and a median of 53%. Law journals have significantly higher average acceptance rate(68%) than other journals, while WOSS journals have the lowest(43%). Findings indicate some of the highest acceptance rates in Social Sciences literature, including competitive Business and Economics journals that traditionally have low acceptance rates. Limitations: Research relies on local context to define publication strategy of editors. Findings may not be generalizable to mainstream journals and core science countries where emphasis on research quality is stronger and editorial selection is base

关键词： Board quality Editorial review Scientific productivity Local journals Insider bias Inside publication

Prescription for Obesity: Eat Less and Move More. Is It Really That Simple?

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Open Journal of Nursing 2014年第9期4卷 656-662页

作者： Karen M. Deck Beth Haney Camille F. Fitzpatrick Susanne J. Phillips Susan M. Tiso core faculty Graduate Nursing Programs University of California Irvine Irvine CA USA

“Obesity is a disease.” This is the declaration by the American Medical Association in June, 2013. The purpose of this article is to provide an overview of options for patients who meet the criteria of obesity. Primary care nurse practitioners are urged to confront obesity head on, with early, individualized intervention to reduce associated morbidity and mortality. Options for weight loss and maintenance are abundant and often confusing or unattractive to the patient. Working with patients to achieve realistic, reasonable, and patient-tailored goals for weight loss and exercise programs are paramount to achieving a healthy weight and lifestyle.

关键词： Obesity Management Options