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Sexual Perception of Young Lebanese Students

Health 2017年第2期9卷 299-316页

作者： Ghada Bteich Mariana Hajj eliane Accaoui abir el abed Faculty of Public Health Lebanese University Branch V Saida Lebanon Faculty of Human Science Lebanese University Dekkwayne Lebanon

This article presents the sexual perception of young Lebanese students. We hypothesized that, in Lebanon and the Arab countries, premarital sex is forbidden by most cultures because of conservative societies and backgrounds. Sexuality lives as a “myth” in these conservative societies. We examined the influence of demographics and genders among a group of 706 Lebanese university students, from public and private universities, as well as the fluctuation of sexual beliefs and practices, based on their gender, demographics and social pressure. The method used was a questionnaire collected form n = 706 students, 446 females and 260 males. The female population of our sample is 62.9% of the total volunteers while the male population is 36.7%. They come from different religions (Christian, Muslim, Druze and Other), between May 2015 and December 2015. Quantitative significant results: 1) A non-conformity with the social and demographic pressure and an openness of the new generations. Similarly, it shows more permissiveness in flirting. Even though, parts of the negative answers were significantly linked to understanding the rules of prohibited sex (NO 32.4% for belief and NO 34.5% for practice);2) the reality of Lebanese youth, their integrity in engaging in a relationship, and their true daily happening of social and peer pressure;3) An opening to a natural outlook of sexual life, (25.5%) with reluctance on dating (51.1%);4) An important significance is showed in the percentage between beliefs and practice: 18% in belief and 78.3% in practice (Q1) and 34.2% in belief and 60.8% in practice (Q2) emphasizing on the reality of sexual engagement within Lebanese youth;5) However, reluctance in engaging in sexual activity and attachment and fear to social sanctions toward premarital sex and agreeing on abstinence before marriage. Quantitative findings supported the lack of sexual education and the prevalence of religious and social norms. This article examines Young Lebanese adol

关键词： Young Lebanese Adolescents University Students Sexuality Perception Premarital Sex Sex Education Dating

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A new hydrophobic deep eutectic solvent composed of menthol and tris(2-ethylhexyl) phosphate for solvent bar microextraction of parabens from biological fluids

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Emerging Contaminants 2024年第2期10卷 135-145页

作者： Nabil N.AL-Hashimi Husam abed Alfattah Khaleel I.Assaf Asma A.Fakhoury Saja H.Hamed Amjad H.el-Sheikh Khairi M.Fahelelbom The Hashemite University Faculty of Pharmaceutical SciencesDepartment of Pharmaceutical ChemistryP.O.Box 330127Zarqa13133Jordan The Hashemite University Faculty of ScienceDepartment of ChemistryP.O.Box 150459Zarqa13115Jordan Al-Balqa Applied University Faculty of ScienceDepartment of Chemistry19117 Al-SaltJordan The Hashemite University Faculty of Pharmaceutical SciencesDepartment of Pharmaceutics and Pharmaceutical TechnologyP.O.Box 330127Zarqa13133Jordan Al Ain University College of PharmacyDepartment of Pharmaceutical SciencesP.O.Box 64141Al AinAl AinUnited Arab Emirates

Parabens are antimicrobial preservatives with extensive applications in cosmetics,toiletries,pharmaceuticals,and *** the legitimate concerns relating to their potential to disrupt multiple endocrine functions,it becomes imperative to prioritize the development of innovative bioanalytical techniques for effectively monitoring their presence in biological *** this study,an efficient solvent bar microextraction(SBME)was established,utilizing new hydrophobic deep eutectic solvents(DEs)to determine methylparaben and propylparaben in urine and plasma *** DEs comprising menthol and tris(2-ethylhexyl)phosphate(M-TEHP)at various molar ratios were synthesized for the first time to enhance the extraction capacity and promote the eco-friendliness of the DE used as an extraction ***-transform infrared(FT-IR)and proton nuclear magnetic resonance(1H NMR)spectroscopies were employed to confirm and investigate the properties of the successful synthesis(M-TEHP)DE at a molar ratio of 1:*** synthesized DE exhibits low microbial toxicity and can be considered an eco-friendly solvent for ***,quantum-chemical calculations were utilized to predict synthesized DE's structure and interaction energy with selected *** influential operational factors of DE-SBME on the extraction efficiency(EE%)of both parabens were evaluated using response surface methodology based on central composite design,and a total of 30 extraction tests were conducted to determine the optimal *** optimized DE-SBME,in combination with HPLC-DAD,exhibited low detection limits(0.54–0.91μg L^(−1)),excellent linearity(R^(2)≥0.9993),precise results(RSDs≤7.6%),satisfactory recoveries(92–97%)and negligible matrix ***,it had remarkable effectiveness and applicability in determining selected parabens in real urine and plasma samples.

关键词： Hydrophobic deep eutectic solvent Solvent bar microextraction Parabens Response surface methodology and central composite design HPLC-DAD Urine and plasma

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Stability analysis of a time-delayed Van der Pol–Helmholtz–Duffing oscillator in fractal space with a non-perturbative approach

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Communications in Theoretical Physics 2024年第4期76卷 22-31页

作者： Yusry O el-Dib Department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

The time-delayed fractal Van der Pol–Helmholtz–Duffing(VPHD)oscillator is the subject of this paper,which explores its mechanisms and highlights its stability *** time-delayed technologies are currently garnering significant attention,the focus of this research remains crucially relevant.A non-perturbative approach is employed to refine and set the stage for the system under *** innovative methodologies introduced yield an equivalent linear differential equation,mirroring the inherent nonlinearities of the ***,the incorporation of quadratic nonlinearity into the frequency formula represents a cutting-edge *** analytical solution's validity is corroborated using a numerical *** conditions are ascertained through the residual Galerkin ***,it is observed that the delay parameter,in the context of the fractal system,reverses its stabilizing influence,impacting both the amplitude of delayed velocity and the *** analytical solution's precision is underscored by its close alignment with numerical ***,the study reveals that fractal characteristics emulate damping *** its applicability across diverse nonlinear dynamical systems,this non-perturbative approach emerges as a promising avenue for future research.

关键词： Van der Pol-Helmholtz-Duffing oscillator fractal space time-delay non-perturbative approach stability analysis el-Dib's frequency formula

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Comparison between seismic analysis of twisting and regular 52-story towers considering soil-structure interaction

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 663-675页

作者： Mohamed Naguib Abouelsaad Mohammed Shaaban Salah el Bagalaty Mohamed E.el Madawy Structural Engineering Department Faculty of EngineeringMansura UniversityMansoura 35511Egypt Faculty of Engineering Delta University for Science and TechnologyGamasa 35712Egypt

A dynamic analysis of both twisting and regular towers is carried out to determine the results of considering soil-structure interaction(SSI)on high-rise *** addition,the difference between the seismic performance of using twisting towers over regular ones is *** twisting tower is a simulation of the Evolution Tower(Moscow).The towers’skeletons consist of RC elements and rest on a reinforced concrete piled-raft *** soil model is considered as multi-layered with the same soil properties as the zone chosen for the analysis(New Mansoura City,Egypt).The only difference between both towers is their shape in *** whole system is modelled and analyzed in a single step as one full 3D model,which is known as the direct approach in *** analyses are carried out using finite-element software(Midas GTS NX).Dynamic output responses due to three records of seismic loads are proposed and presented in some *** on the results,it is concluded that SSI has a considerable effect on the dynamic response of tall buildings mainly because of the foundation flexibility,as it leads to lengthening the vibration period,increasing the story drift and the base shear for both cases.

关键词： soil-structure interaction seismic analysis twisting towers base shear story drift finite element method Midas GTS NX

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Gender-Based Analysis of User Reactions to Facebook Posts

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Big Data Mining and Analytics 2024年第1期7卷 75-86页

作者： Yassine el Moudene Jaafar Idrais Rida el Abassi Abderrahim Sabour Mathematical Engineering and Computer Science Laboratory Faculty of SciencesIbn Zohr UniversityAgadir 8706Morocco Department of Computer Science Mathematical−High School of Technology Ibn Zohr UniversityAgadir 8706Morocco

Online Social Networks(OSNs)are based on the sharing of different types of information and on various interactions(comments,reactions,and sharing).One of these important actions is the emotional reaction to the *** diversity of reaction types available on Facebook(namely FB)enables users to express their feelings,and its traceability creates and enriches the users’emotional identity in the virtual *** paper is based on the analysis of 119875012 FB reactions(Like,Love,Haha,Wow,Sad,Angry,Thankful,and Pride)made at multiple levels(publications,comments,and sub-comments)to study and classify the users’emotional behavior,visualize the distribution of different types of reactions,and analyze the gender impact on emotion *** of these can be achieved by addressing these research questions:who reacts the most?Which emotion is the most expressed?

关键词： profiling knowledge extraction data mining emotion mining social media data crawling Facebook reactions gender

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Existence results and behavior analysis for nonlinear age-dependent population dynamics problems with conformable fractional operator

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International Journal of Biomathematics 2024年第5期17卷 229-256页

作者： Hiba el Asraoui M'hamed el Omari Ali el Mfadel Khalid Hilal Laboratory of Applied Mathematics Scientific Computing Sultan Moulay Slimane University BP 523 Beni MellalMorocco

In this paper,we investigate the existence of solutions and analyze the large-time behavior for Gurtin-Maccamy population model involving conformable fractional *** a preliminary step,we construct a generic structure of the solution associated with our proposed model by utilizing some basic properties and tools of conformable fractional *** establish the existence of a unique solution of the given model with the given initial *** last,by using the upper and lower solutions for the characteristic equation,we define the upper and lower boundaries for the obtained solution and describe the large-time behavior of the total population.

关键词： Age-dependent population conformable fractional operator upper and lower boundary of the solution dynamics of populations

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Nonlinear wave dispersion in monoatomic chains with lumped and distributed masses:discrete and continuum models

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 633-648页

作者： E.GHAVANLOO S.el-BORGI School of Mechanical Engineering Shiraz UniversityShiraz 71963-16548Iran Mechanical Engineering Program Texas A&M University at QatarDoha 23874Qatar

The main objective of this paper is to investigate the influence of inertia of nonlinear springs on the dispersion behavior of discrete monoatomic chains with lumped and distributed *** developed model can represent the wave propagation problem in a non-homogeneous material consisting of heavy inclusions embedded in a *** inclusions are idealized by lumped masses,and the matrix between adjacent inclusions is modeled by a nonlinear spring with distributed ***,the model is capable of depicting the wave propagation in bi-material bars,wherein the first material is represented by a rigid particle and the second one is represented by a nonlinear spring with distributed *** discrete model of the nonlinear monoatomic chain with lumped and distributed masses is first considered,and a closed-form expression of the dispersion relation is obtained by the second-order Lindstedt-Poincare method(LPM).Next,a continuum model for the nonlinear monoatomic chain is derived directly from its discrete lattice model by a suitable continualization *** subsequent use of the second-order method of multiple scales(MMS)facilitates the derivation of the corresponding nonlinear dispersion relation in a closed *** novelties of the present study consist of(i)considering the inertia of nonlinear springs on the dispersion behavior of the discrete mass-spring chains;(ii)developing the second-order LPM for the wave propagation in the discrete chains;and(iii)deriving a continuum model for the nonlinear monoatomic chains with lumped and distributed ***,a parametric study is conducted to examine the effects of the design parameters and the distributed spring mass on the nonlinear dispersion relations and phase velocities obtained from both the discrete and continuum *** parameters include the ratio of the spring mass to the lumped mass,the nonlinear stiffness coefficient of the spring,and the wave amplitude.

关键词： nonlinear mass-spring chain discrete model continuum model LindstedtPoincare method(LPM) method of multiple scales(MMS) dispersion phase velocity

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Modeling environmental sensitivity and risk assessment of PAHs in sediments along two marine coastal areas in Egypt

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Petroleum Research 2024年第1期9卷 125-142页

作者： Muhammad A.el-Alfy National Institute of Oceanography and Fisheries NIOFCairoEgypt

Modeling the environmental sensitivity index(ESI)is vital in the planning and management processes,especially along the coastal *** main objectives of the study were to define the main sources of polycyclic aromatic hydrocarbons(PAHs),establish an ESI model,and measure the risk of PAHs on humans and the environment using various *** methodology of the research involved analyzing PAHs according to the EPA 550 methodology in sediments of the coastline in two important coastline areas in Egypt,namely the Gulf of Suez and the Mediterranean Sea,modeling the sensitivity of PAHs using ArcGIS 10.5 by integrating different physical,biological,and land use/cover factors,identifying the sources,and performing a risk *** sediment samples were collected from each *** produced sensitivity map could explain the highly sensitive areas along the Mediterranean Sea and Gulf of Suez coastlines(especially areas that were near drains'outlets,industrial sites,and sea ports).The highest mean PAH concentrations were Acenaphthylene and Fluorine in the Mediterranean Sea and Suez Gulf,***'s obvious that the individual PAH concentrations were within the ERL,ERM,and Pel threshold limits,indicating no adverse biological *** ratios of BaA/BaA+Chy,Flu/Flu+Py,and Ant/Ant+Phe gave an indication that most PAH sources were petrogenic(63.64%)and others(36.36%)were from petroleum *** principle component analysis(PCA)indicated a diverse correlation among the isomer ratios and LU/LC *** carcinogenic risk values were in the very low category(elines and seawater free of oil spillage act

关键词： Polycyclic aromatic hydrocarbons(PAHs) Modeling Sensitivity Gulf of Suez And Mediterranean sea

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Detection of internal crack growth in polyethylene pipe using guided wave ultrasonic testing

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 319-329页

作者： Jay Kumar Shah Hao Wang Said el-Hawwat Centre of Advanced Infrastructure and Transportation RutgersThe State University of New JerseyNJ 08854USA Department of Civil and Environmental Engineering RutgersThe State University of New JerseyNJ 08854USA

Despite the success of guided wave ultrasonic inspection for internal defect detection in steel pipes,its application on polyethylene(PE)pipe remains relatively *** growth of internal cracks in PE pipe severely affects its pressure-holding capacity,hence the early detection of internal cracks is crucial for effective pipeline maintenance *** study extends the scope of guided wave-based ultrasonic testing to detect the growth of internal cracks in a natural gas distribution PE *** experiments and a finite element model were planned to study the wave-crack interaction at different stages of axially oriented internal crack growth with a piezoceramic transducer-based setup arranged in a pitch-catch *** dispersion analysis supplemented with preliminary experiments was performed to isolate the optimal inspection frequency,leading to the selection of the T(0,1)mode at 50-kHz for the investigation.A transmission index based on the energy of the T(0,1)mode was developed to trace the extent of simulated crack *** findings revealed an inverse linear correlation between the transmission index and the crack depth for crack growth beyond 20%crack depth.

关键词： polyethylene pipes internal cracks guided wave ultrasonic testing torsional modes finite element modeling

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Profiles of the Headspace Volatile Organic and Essential Oil Compounds from the Tunisian Cardaria draba (L.) Desv. and Its Leaf and Stem Epidermal Micromorphology

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Phyton-International Journal of Experimental Botany 2024年第4期93卷 725-744页

作者： Wissal Saadellaoui Samiha Kahlaoui Kheiria Hcini abir Haddada Noomene Sleimi Roberta Ascrizzi Guido Flamini Fethia Harzallah-Skhiri Sondes Stambouli-Essassi Laboratory of Biodiversity Biotechnology and Climate Change(LR11-ES09)Faculty of Sciences of TunisUniversity of Tunis El ManarTunis1060Tunisia Laboratory RME-Resources Materials and EcosystemsFaculty of Sciences of BizerteUniversity of CarthageJarzounaBizerte7021Tunisia Dipartimento di Farmacia Universitàdi PisaVia Bonanno 33Pisa56126Italy Laboratory of Bioresources:Integrative Biology and Valorization(LR14-ES06) High Institute of Biotechnology of MonastirUniversity of MonastirMonastir5000Tunisia

In this work, we investigated aroma volatiles emanated by dry roots, stems, leaves, flowers, and fruits of Cardariadraba (L.) Desv. growing wild in Tunisia and its aerial part essential oils (EOs) composition. A total of 37 volatileorganic compounds (96.7%–98.9%) were identified;4 esters, 4 alcohols, 7 hydrocarbons, 12 aldehydes, 5 ketones,1 lactone, 1 organosulfur compound, 2 organonitrogen compounds, and 1 acid. The hydrocarbons form the maingroup, representing 49.5%–84.6% of the total detected volatiles. The main constituent was 2,2,4,6,6-pentamethylheptane(44.5%–76.2%) reaching the highest relative percentages. Forty-two compounds were determined in thetwo fractions of EOs, representing 98.8% and 97.2% of the total oil composition, respectively. The principal componentswere hexadecanoic acid (34.6%), 6-methyl-5-hepten-2-one (18.3%), decanal (15.0%), 6,10,14-trimethyl-2-pentadecanone (13.2%), and n-pentacosane (13%). Micromorphological details of the leaf and stem epidermisusing light microscopy revealed polygonal cells with sinuous walls in the adaxial and abaxial leaf surfaces andnearly rectangular and long ones with linear and thick walls for the stem epidermis. The stomata complexes wereanisocytic in the leaf epidermis and mainly anisocytic and rarely paracytic in the stem epidermis. Non-glandulartrichomes were unbranched and long with an acute apex or short with a convex apex. The glandular ones wereidentified for the first time in this species. They were short-stalked with a large secretory head. The highest stomatalindex (17.02%) was recorded in the abaxial leaf surface. The identification of headspace volatiles and essentialoil compounds can be used to characterize this species, and the various epidermis micromorphologicalfeatures are very useful for biosystematics taxonomic studies within Brassicaceae.

关键词： Cardaria draba aroma profile essential oils epidermis trichomes

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