A minimal HIV-AIDS infection model with general incidence rate and application to Morocco data

We study the global dynamics of a SICA infection model with general incidence rate. The proposed model is calibrated with cumulative cases of infection by HIV-AIDS in Morocco from 1986 to 2015. We first prove that our model is biologically and mathematically well-posed. Stability analysis of different steady states is performed and threshold parameters are identified where the model exhibits clearance of infection or maintenance of a chronic infection. Furthermore, we examine the robustness of the model to some parameter values by examining the sensitivity of the basic reproduction number. Finally, using numerical simulations with real data from Morocco, we show that the model predicts well such reality.Comment: This is a preprint of a paper whose final and definite form is with 'Statistics Opt. Inform. Comput.', Vol. 7, No 2 (2019). See [http://www.IAPress.org]. Submitted 16/Sept/2018; Revised 10 & 15/Dec/2018; Accepted 15/Dec/201

Synthesis and characterization of two novel antibacterial dendritic methacrylate-based dental monomers

504-513This study explores the synthesis and characterization of two novel antibacterial dendritic methacrylate-based dental monomers. For this purpose, two dendritic esters have been synthesized via condensation reaction and then reacted with methacryloyl chloride to afford methacrylate-end caped dendritic esters. These compounds are subsequently converted to quaternary ammonium fluoride monomers (QAFMs) with decyl substituted side chain to produce two novel antibacterial dendreticdental monomers. The chemical structures of synthesized samples have been characterized using Fourier transform infrared (FTIR) and proton nuclear magnetic resonance (1H NMR) spectroscopies.The obtained monomers can be used to replace 2,2-bis[4-(2-hydroxy-3-methacryloyloxypropyl)-phenyl]propane (Bis-GMA) as the base monomer of universal resin-based dental composites in the presence of a diluting monomer (e.g.,triethyleneglycoldimethacrylate; TEGDMA), mainly due to their superior characteristics such as multifunctionalities as well as antibacterial activities

Synthesis and characterization of two novel antibacterial dendritic methacrylate-based dental monomers

This study explores the synthesis and characterization of two novel antibacterial dendritic methacrylate-based dental monomers. For this purpose, two dendritic esters have been synthesized via condensation reaction and then reacted with methacryloyl chloride to afford methacrylate-end caped dendritic esters. These compounds are subsequently converted to quaternary ammonium fluoride monomers (QAFMs) with decyl substituted side chain to produce two novel antibacterial dendreticdental monomers. The chemical structures of synthesized samples have been characterized using Fourier transform infrared (FTIR) and proton nuclear magnetic resonance (1H NMR) spectroscopies.The obtained monomers can be used to replace 2,2-bis[4-(2-hydroxy-3-methacryloyloxypropyl)-phenyl]propane (Bis-GMA) as the base monomer of universal resin-based dental composites in the presence of a diluting monomer (e.g.,triethyleneglycoldimethacrylate; TEGDMA), mainly due to their superior characteristics such as multifunctionalities as well as antibacterial activities

Évolution de la place du végétal dans la ville, de l’espace vert a la trame verte

International audienceSince the XIX century, the role of green space in French urban policies underwent significant changes. Regarding the objectives of planning, we can identify three periods in which new management practices and many novel typologies of green spaces appeared : functionalist urban planning, sustainable urban planning and ecological urban planning. Therefore, the evolution of urban green spaces was based on “naturalness gradient” : from private garden with a high aesthetic level to multipurpose urban greenways. Nowadays, studies that focus on “nature” in the city are based on tow principles : (i) the evaluation of ecosystem services and (ii) the connectivity of particular habitats. The aim of this paper is to trace the historic evolution of the role of green areas in cities with reference to the diverse theories and practices of urban planning.La place attribuée aux espaces verts par les politiques urbaines depuis le XIXe siècle en France a connu plusieurs phases. Selon les tendances urbanistiques adoptées, trois périodes principales peuvent être identifiées : il s’agit de l’ère de l’urbanisme fonctionnaliste, de celle de l’urbanisme durable et enfin l’émergence de l’urbanisme écologique. Tout au long de ces périodes, de nouvelles pratiques de gestion et différentes typologies d’espaces verts sont apparues. Les espaces végétalisés urbains ont ainsi évolué par rapport à un « gradient de naturalité », allant des jardins privés à forte valeur ornementale à la trame verte urbaine multifonctionnelle. De nos jours, les études menées sur « la nature » en ville se structurent en fonction de deux orientations principales : (i) l’évaluation des services écosystémiques rendus par la biodiversité et (ii) la mise en connectivité des habitats particuliers. L’objectif de cet article est de proposer une synthèse de l’évolution de la place du végétal en ville à la fois dans les diverses théories urbanistiques et dans les pratiques urbanistiques

Predictors of malnutrition among Zahedan& rsquo s children age ranging from 2-5 years old in 2007-2008

چکیده: زمینه و هدف: ارزیابی دوره‌ای شاخص‌های تن سنجی یکی از مناسب ترین ابزارهای پایش وضعیت تغذیه کودکان در یک منطقه بوده و منبع اطلاعات خوبی به عنوان مرجع برای نظام مدیریت بخش سلامت کشور و شاخصی از عدالت در جامعه می‌باشد. هدف این مطالعه تعیین میزان شیوع هر کدام از شاخص های سوء تغذیه در کودکان 5-2 سال و پیشگویی کننده های آن می باشد. روش بررسی: در این مطالعه توصیفی- تحلیلی تعداد 1245 کودک 5-2 سال از 5 منطقه شهری شهر زاهدان به صورت چند مرحله ای انتخاب و بررسی شدند. اطلاعات با استفاده از پرونده ها و مصاحبه با مادر کودک جمع آوری شد. در این مطالعه سه شاخص وزن برای قد، قد برای سن و وزن برای سن به ترتیب به عنوان نمایه وضع تغذیه زمان حال یا لاغری، زمان گذشته یا کوتاه قدی و زمان حال و گذشته یا کم وزنی بر اساس 5/2-Z= مورد بررسی قرار گرفت. داده ها با استفاده از آزمون های t مستقل و مجذور کای و رگرسیون خطی مورد تجزیه و تحلیل قرار گرفت. یافته‌ها: میزان شیوع لاغری، کوتاه قدی وکم وزنی به ترتیب 2/4، 6/7 و 4/3 برآورد شد. در تحلیل تک متغیره، لاغری با وزن هنگام تولد و فاصله تولد، کوتاه قدی با وزن هنگام تولد، تحصیلات مادر، شغل پدر، نوع تغذیه زیر یکسال، سابقه عفونت، فاصله تولد و سن مادر و کم وزنی نیز با جنس، وزن هنگام تولد، نوع تغذیه زیر یکسال، سابقه عفونت، فاصله تولد و سن مادر رابطه معنی داری نشان دادند (05/0

Effects of storage duration and conditions on mechanical properties of Viola cucumber fruit under compression loading

In this research, the effects of storage duration and storage conditions on mechanical properties of cucumber fruit (Viola variety) were evaluated at different positions of the fruit length.  The cucumber fruit mechanical properties determined in this study were firmness, apparent modulus of elasticity, failure stress, failure strain and failure energy.  The mechanical properties determined under compression loading using puncture and uni-axial compression tests.  The results showed that the storage duration, storage conditions and fruit test position had significant (P<0.01) effect on the mechanical properties of Viola cucumber fruit.  The samples firmness, modulus of elasticity, failure stress and failure energy reduced about 49%, 39%, 38% and 33%, respectively during shelf life.  The failure strain of samples increased 18% during storage time.  Changing the mechanical properties of the cucumber fruit at room conditions was faster than refrigerator conditions.  The mechanical properties were differed along the length of cucumber fruits so that near the stem region of cucumber fruit had the maximum value of firmness, modulus of elasticity, failure stress and failure energy.  The sample failure strain had the minimum value at near the stem region of cucumber fruit.  Among the mechanical parameters that were evaluated in this research work, the firmness can be considered as the most appropriate parameter to evaluate textural properties of Viola cucumber fruit due to significant effect of independent parameters on it and ease of usage

Structural Topology Optimization: Moving Beyond Linear Elastic Design Objectives

Topology optimization is a systematic, free-form approach to the design of structures. It simultaneously optimizes material quantities and system connectivity, enabling the discovery of new, high-performance structural concepts. While powerful, this design freedom has a tendency to produce solutions that are unrealizable or impractical from a structural engineering perspective. Examples include overly complex topologies that are expensive to construct and ultra-slender subsystems that may be overly susceptible to imperfections. This paper summarizes recent tools developed by the authors capable of mitigating these shortcomings through consideration of (1) constructability, (2) nonlinear mechanics, and (3) uncertainties

Study on transferred impulse and response of steel plate walls under various impulsive loading considering mesh size effects

The behavior of steel plate walls (SPWs) under various impulsive loadings and the effects of different mesh sizes are investigated in this paper. With the aim of accurately inspecting SPWs, a series of analyses with 250 models with different plate geometric assumptions and different blast impulsive loadings are performed to study the SPWs’ out-of-plane behavior. The mild steel material specifications are adopted for SPWs with different thickness and stiffener arrangement and ABAQUS software is utilized for the Finite Element analysis. Results of transferred impulse, maximum displacement and Von   Mises stress of SPWs show that SPWs with thickness of 5 mm are the best choice against various impulsive loadings in comparison with SPWs with thickness of 20 mm. In fact, the SPWs having the thickness of 5 mm show better performance as a result of more energy dissipation against various impulsive loadings. Finally, the Von Mises stress contours investigated for some models show 28% more stress in P5 SPW than that in P20 SPW. Also, it can be concluded that various sizes of mesh have no remarkable effect on unstiffened SPW while effect of different mesh sizes is more significant with increasing the number of stiffeners