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REGULARITY OF SOLUTIONS TO NONLINEAR TIME FRACTIONAL DIFFERENTIAL EQUATION

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Acta Mathematica Scientia 2013年第6期33卷 1721-1735页

作者： mirjana STOJANOVI Department of Mathematics and Informatics University of Novi Sad

We find an upper viscosity solution and give a proof of the existence-uniqueness in the space C^∞（t∈（0,∞）;H2^s＋2（R^n））∩C^0（t∈[0,∞）;H^s（R^n））,s∈R,to the nonlinear time fractional equation of distributed order with spatial Laplace operator subject to the Cauchy conditions ∫0^2p（β）D＊^βu（x,t）dβ=△xu（x,t）＋f（t,u（t,x））,t≥0,x∈R^n,u（0,x）=φ（x）,ut（0,x）=ψ（x）,（0.1） where △xis the spatial Laplace operator,D＊^β is the operator of fractional differentiation in the Caputo sense and the force term F satisfies the Assumption 1 on the regularity and growth. For the weight function we take a positive-linear combination of delta distributions concentrated at points of interval （0, 2）, i.e., p（β） =m∑k=1bkδ（β-βk）,0〈βk〈2,bk〉0,k=1,2,…,*** regularity of the solution is established in the framework of the space C^∞（t∈（0,∞）;C^∞（R^n））∩C^0（t∈[0,∞）;C^∞（R^n））when the initial data belong to the Sobolev space H2^8（R^n）,s∈R.

关键词： nonlinear time-fractional equations of distributed order existence-uniqueness theorems viscosity solutions regularity result

Nonlinear Parabolic Equations with Singularities in Colombeau Vector Spaces

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Acta Mathematica Sinica,English Series 2006年第2期22卷 393-406页

作者： mirjana STOJANOVI Department of Mathematics and Informatics Faculty of Science University of Novi Sad

We consider nonlinear parabolic equations with nonlinear non-Lipschitz＇s term and singular initial data like Dirac measure, its derivatives and powers. We prove existence-uniqueness theorems in Colombeau vector space yC^1,W^2,2（[0,T）,R^n）,n ≤ 3. Due to high singularity in a case of parabolic equation with nonlinear conservative term we employ the regularized derivative for the conservative term, in order to obtain the global existence-uniqueness result in Colombeau vector space yC^1,L^2（[0,T）,R^n）,n≤ 3.

关键词： nonlinear parabolic equation parabolic equation with nonlinear conservative term singular initial data Colombeau vector spaces regularized derivatives existence-uniqueness theorems

Isotropic Affine Spheres

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Acta Mathematica Sinica,English Series 2012年第10期28卷 1955-1972页

作者： Olivier BIREMBAUX mirjana DJORI Université Lille Nord de France F-59000 Lille Laboratoire de Mathématiques et ses Applications de Valenciennes Université de Valenciennes et du Hainaut Cambrésis Faculty of Mathematics University of Belgrade Studentski trg 16

In this paper, we study affine spheres which are isotropic and we obtain a complete clas- sification. In particular, we show that all such afline spheres are hyperbolic afiine spheres, isometric with SL（3, R）/SO（3... 详细信息

关键词： Afline sphere isotropic submanifold symmetric space

Long term sediment transport simulation of the Danube,Sava,and Tisa rivers

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International Journal of Sediment Research 2020年第5期35卷 550-561页

作者： mirjana Horvat Zoltan Horvat University of Novi Sad Faculty of Civil Engineering Subotica

The aim of this paper is to evaluate a newly developed one dimensional unsteady flow,sediment transport and bed evolution model for a looped river network through a long term simulation of a reallife *** model was assessed by verifying it for the Danube,Tisa,and Sava rivers in Serbia for a five year time *** total length of the modeled domain was 741.94 km from which 486.48 km is the length of the modeled Danube River reach,132.50 km the modeled section of the Sava and 122.96 km the length of the modeled Tisa River *** simulated domain included smaller tributaries such as the Kolubara,Mlava,Nera,Pek,Porecka,Tamis,and Great Morava *** to the size of the domain that was included in the model,the work also includes extensive research regarding the available measurements,issues with measurement errors,and suggestions on overcoming incomplete measurements by developing different types of *** attained results were analyzed by comparing the simulation results with measured water levels,discharges,and suspended sediment *** implemented evaluation of the results confirmed the developed model's reliability.

关键词： 1-D sediment transport Looped river network Long term simulation Calibration Verification

Protective effects of exogenous gangliosides on ROS-induced changes in human spermatozoa

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Asian Journal of Andrology 2013年第3期15卷 375-381页

作者： mirjana Gavella Vaskresenija Lipovac Reproductive Biochemistry and Cell Metabolism Unit Institute of Clinical Chemistry and Laboratory Medicine Merkur University Hospital Zagreb 10000 Croatia

This article summarizes the available evidence on the efficacy of gangliosides to reduce the degree of reactive oxygen species （ROS）-mediated damage. The antioxidative efficacy of exogenous gangliosides in protecting different cells encouraged us to examine their ability to protect human spermatozoa. Gangliosides are sialic acid-containing glycosphingolipids with strong amphiphilic character due to the bulky headgroup made of several sugar rings with sialic acid residues and the double-tailed hydrophobic lipid moiety. The amphiphilicity of gangliosides allows them to exist as micelles in aqueous media when they are present at a concentration above their critical micellar concentration. The protective effect of ganglioside micelles on spermatozoa is believed to stem from their ability to scavenge free radicals and prevent their damaging effects, In our study, we particularly focused our attention on the protective effect of ganglioside micelles on DNA in human spermatozoa exposed to cryopreservation. The results indicate that ganglioside micelles can modulate the hydrophobic properties of the sperm membrane to increase tolerance to DNA fragmentation, thus protecting the DNA from cryopreservation-induced damage. Further actions of ganglioside micelles, which were documented by biochemical and biophysical studies, included （i） the modulation of superoxide anion generation by increasing the diffusion barrier for membrane events responsible for signal translocation to the interior of the cell; （ii） the inhibition of iron-catalysed hydroxyl radical formation due to the iron chelation potential of gangliosides; and （iii） inhibition of hydrogen peroxide diffusion across the sperm membrane.

关键词： exogenous gangliosides oxidative stress protection spermatozoa

Understorey species distinguish late successional and ancient forests after decades of minimum human intervention: A case study from Slovenia

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Forest Ecosystems 2023年第1期10卷 92-101页

作者： mirjana Sipek Tim Ravnjak Nina Sajna University of Maribor Faculty of Natural Sciences and MathematicsKoroska c.1602000MariborSlovenia

The main species composition drivers in temperate deciduous forests are environmental conditions, a stand?s age and the site history, e.g., the succession stage and past land use, as well as disturbance regime and current management. We compared plant species diversity and composition in late successional and ancient forests, cooccurring on the same small river island applying species accumulation curves and nonmetric multidimensional scaling, respectively. Given the island?s geomorphological characteristics, we expected these to be very similar before human intervention in the past. The forests experienced differing disturbance regimes in the past, while over the last 30 years, human intervention has been the same and reduced to a minimum. The ancient forest in this study had two major characteristics defining it as old, mature forest: continuity of presence for more than 200years and specific composition. The late successional forest experienced major disturbance in the 20th century and was allowed natural regeneration by bordering on the ancient forest, representing a potential species pool,and by decades of minimum human intervention. Our results showed that, even though there was no difference in species richness, we could still detect differences between the forests, particularly in the abundance and species composition of the understorey, among which geophytes had the most indicative importance. To make our results useful on a broader scale, we composed from the literature a species list of plants indicative for ancient forest and tested its application. These results are important for distinguishing between old and mature secondary stands and particularly for identifying old forest stands, which should be conserved and, in the case of fragmented landscapes, included in a network connecting forest fragments.

关键词： Forest community Successional forest Indicator plants Plant diversity Understorey Geophytes

Inducing neuronal regeneration and differentiation via the BDNF/ TrkB signaling pathway: a key target against neurodegenerative diseases?

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Neural Regeneration Research 2024年第3期19卷 495-496页

作者： mirjana Antonijevic Patrick Dallemagne Christophe Rochais Normandie University UNICAENCERMNCaenFrance

Brain-derived neurotrophic factor(BDNF)is one of the neurotrophins,a specific polypeptide growth factor,which plays a crucial role in the proliferation,differentiation,survival,and death of neurons and non-neuronal *** is not only essential to maintain the balance between death on one side and survival of neurons on the other,but also it mediates additional higher-order activities such as learning,memory,and *** is initially synthesized as a precursor protein,proBDNF,that can be secreted as it is or it can be cleaved intracellularly by furin and proconvertases,or extracellularly by extracellular proteases such as matrix metalloprotease-9 and matrix metalloprotease-2,or plasmin to give mature BDNF.

关键词： death diseases degenerative

Characterization of Totally Geodesic Totally Real 3-dimensional Submanifolds in the 6-sphere

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Acta Mathematica Sinica,English Series 2006年第5期22卷 1557-1564页

作者： Miroslava ANTIC mirjana DJORIC Luc VRANCKEN Faculty of Mathematics University of BelgradeStudentski trg 16 pb. 550 11000 Belgrade Serbia and Montenegro LAMATH ISTV2 Université de Valenciennes Campus du Mont Houy59313 Valenciennes Cedex 9 France

In this paper, we study Lagrangian submanifolds of the nearly Kaehler 6-sphere. We derive a pinching result for the Ricci curvature of such submanifolds thus providing a characterisation of the totally geodesic subman... 详细信息

关键词： Ricci curvature totally real submanifold nearly Kaehler 6-sphere totally geodesic submanifold

Comparison of iron aluminide Fe_(3)Al with armour steel in ballistic behaviour OA

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Defence Technology（防务技术） 2024年第12期42卷 183-190页

作者： Pavel Hanus Milan Pecanac mirjana Trivkovic Savo Bojic Sebastian Balos Technical University of Liberec Faculty of EngineeringDepartment of Material ScienceStudentska 2CZ 46117LiberecCzech Republic University of Novi Sad Faculty of Technical SciencesDepartment of Production EngineeringTrg Dositeja Obradovica 621000Novi SadSerbia University of Novi Sad Faculty of Technical SciencesMechanization and Construction EngineeringTrg Dositeja Obradovica 621000Novi SadSerbia

Intermetallic aluminide compounds possess several potential advantages compared to alloyed steels,like enhanced oxidation resistance,lower density and the omittance of critical raw *** aluminides,compared to other transition metal-aluminides of TM_(3)-Al type,although having a higher density compared to titan-aluminides,have a lower density compared to nickel-aluminides,but also a higher ductility than both alternatives,making this material potentially effective in ballistic protection ***-wise,this material may be a worthy alternative to armour steels,which was the aim of this *** materials,Fe_(3)Al intermetallic compound(F3A-C)and Armox 500 armour steel were ballistically tested against tungsten-carbide(WC)armour-piercing ammunition,in accordance with STANAG *** ballistic testing,microhardness and metallographic testing were performed,revealing differences in strain hardening,crack propagation mode and exit hole morphology.F3A-C ballistic resistance is similar to that of armour steel,in spite of the lower tensile and impact mechanical properties,relying on a considerably higher strain hardening rate,thermal properties and a lower density.

关键词： Iron aluminide Armour steel Ballistic testing Impact testing Sem microscopy