TIME PERIODIC SOLUTIONS TO THE EVOLUTIONARY OSEEN MODEL FOR A GENERALIZED NEWTONIAN INCOMPRESSIBLE FLUID

In this paper we study a nonstationary Oseen model for a generalized Newtonian incompressible fluid with a time periodic condition and a multivalued,nonmonotone friction law.First,a variational formulation of the model is obtained;that is a nonlinear boundary hemivariational inequality of parabolic type for the velocity field.Then,an abstract first-order evolutionary hemivariational inequality in the framework of an evolution triple of spaces is investigated.Under mild assumptions,the nonemptiness and weak compactness of the set of periodic solutions to the abstract inequality are proven.Furthermore,a uniqueness theorem for the abstract inequality is established by using a monotonicity argument.Finally,we employ the theoretical results to examine the nonstationary Oseen model.

MIXED VARIATIONAL INEQUALITIES DRIVEN BY FRACTIONAL EVOLUTIONARY EQUATIONS

The goal of the present paper is to investigate an abstract system, called fractional differential variational inequality, which consists of a mixed variational inequality combined with a fractional evolution equation in the framework of Banach spaces. Using discrete approximation approach, an existence theorem of solutions for the inequality is established under some suitable assumptions.

ANALYSIS OF AN ELASTO-PIEZOELECTRIC SYSTEM OF HEMIVARIATIONAL INEQUALITIES WITH THERMAL EFFECTS

In this paper we prove the existence and uniqueness of a weak solution for a dynamic electo-viscoetastic problem that describes a contact between a body and a foundation. We assume the body is made from thermoviscoelastic material and consider nonmonotone boundary conditions for the contact. We use recent results from the theory of hemivariational inequalities and the fixed point theory.

A VARIATIONAL-HEMIVARIATIONAL INEQUALITY IN CONTACT PROBLEM FOR LOCKING MATERIALS AND NONMONOTONE SLIP DEPENDENT FRICTION

We study a new class of elliptic variational-hemivariational inequalities arising in the modelling of contact problems for elastic ideally locking materials. The contact is described by the Signorini unilateral contact condition and the friction is modelled by the nonmonotone multivalued subdifferential condition which depends on the slip. The problem is governed by a nonlinear elasticity operator, the subdifferential of the indicator function of a convex set which describes the locking constraints and a nonconvex locally Lipschitz friction potential. The result on existence and uniqueness of solution to the inequality is shown. The proof is based on a surjectivity result for maximal monotone and pseudomonotone operators combined with the application of the Banach contraction principle.

Spring recharge and groundwater flow patterns in flysch aquifer in the Polonina Wetlińska Massif in the Carpathian Mountains

Flysch-type aquifers in the Eastern Carpathians usually feed periodic and low-discharge springs. However, in some areas, such as in the upper part of the Polonina Wetlińska Massif, perennial springs with a relatively high discharge were identified. Therefore, the aim of this study was to identify recharge and groundwater flow patterns of three high-discharge springs based on the response of spring discharge to rainfall and on the relationship between specific electrical conductivity of water and spring discharge. The relation between spring discharge and rainfall was investigated by crosscorrelation analyses. Generally, cumulative rainfall over a period from 10 days to 3 months is most strongly correlated with discharge;however, the response time of spring discharge varies throughout the year. Faster response to rainfall occurs in the spring after snowmelt, while in the summer and autumn months the response time increases. Two flow systems were identified: 1) a relatively deep, fissure-pore flow system with a long response time to precipitation and 2) a shallow, fissure-dominated system with a short response time, which is superimposed on the longer response. A small range of specific electrical conductivity combined with the varying discharge of two springs suggests that dilution of groundwater by rainwater does not play a significant role. The differences in the studied springs’ response to rainfall can be attributed to the recharge area, regolith features and local bedrock structures, i.e. occurrence of joints and faults, monoclinal dip of rock layers and gravitational slope deformations including ridge-top trenches, which, thus far, have been underestimated in determining groundwater storage capacity in the flysch part of the Carpathians.

Flutamide-induced alterations in transcriptional profiling of neonatal porcine ovaries

Background: Androgens are involved in the regulation of ovarian development during fetal/neonatal life.Environmental chemicals displaying anti-androgenic activities may affect multiple signal transduction pathways by blocking endogenous androgen action.The aim of the current study was to examine effects of the anti-androgen flutamide on the expression of coding transcripts and long non-coding RNAs(lncRNAs) in neonatal porcine ovaries.By employing RNA-Seq technology we aimed to extend our understanding of the role of androgens in neonatal folliculogenesis and examine the impact of the anti-androgen flutamide on ovarian function.Method: Piglets were subcutaneously injected with flutamide(50 mg/kg BW) or corn oil(controls) between postnatal days 1 and 10(n = 3/group).Ovaries were excised from the 11-day-old piglets and total cellular RNAs were isolated and sequenced.Results: Flutamide-treated piglet ovaries showed 280 differentially expressed genes(DEGs;P-adjusted < 0.05 and log2 fold change ≥1.0) and 98 differentially expressed lncRNAs(DELs;P-adjusted < 0.05 and log2 FC ≥ 1.0).The DEGs were assigned to GO term,covering biological processes,molecular functions and cellular components,which linked the DEGs to functions associated with cellular transport,cell divisions and cytoskeleton.In addition,STRING software demonstrated strongest interactions between genes related to cell proliferation.Correlations between DEGs and DELs were also found,revealing that a majority of the genes targeted by the flutamide-affected lncRNAs were associated with intracellular transport and cell division.Conclusions: Our results suggest that neonatal exposure of pigs to flutamide alters the expression of genes involved in ovarian cell proliferation,ovarian steroidogenesis and oocyte fertilization,which in turn may affect female reproduction in adult life.

Optimal control of differential quasivariational-hemivariational inequalities with applications

In this paper,we study a new class of differential quasivariational-hemivariational inequalities of the elliptic type.The problem consists of a system coupling the Cauchy problem for an ordinary differential equation with the variational-hemivariational inequalities,unilateral constraints,and history-dependent operators.First,based on the Minty formulation and the continuity of the solution map of a parametrized quasivariational-hemivariational inequality,and a fixed point theorem for a history-dependent operator,we prove a result on the well-posedness.Next,we examine optimal control problems for differential quasivariational-hemivariational inequalities,including a time-optimal control problem and a maximum stay control problem,for which we show the existence of solutions.In all the optimal control problems,the system is controlled through a distributed and boundary control,a control in initial conditions,and a control that appears in history-dependent operators.Finally,we illustrate the results by considering a nonlinear controlled system for a time-dependent elliptic equation with unilateral constraints.

Copernicrinus zamorae gen.et sp.nov.,the oldest thiolliericrinid crinoid(Crinoidea,Echinodermata) from the Bajocian strata of Algeria,Africa

The thiolliericrinids(Thiolliericrinidae) are comatulids(Comatulida),which retained their stalks as adults.Here,we report a centrodorsal from the Bajocian strata(Middle Jurassic) of the Djebel Kérdacha area,northwestern Algeria(Africa).It is the first thiolliericrinid report from outside of Europe and also the oldest representative of the Thiolliericrinidae whose first occurrence is from the Oxfordian.The crinoid is assigned to Copernicrinus zamorae gen.et sp.nov.The reported new taxon shows strong similarities with the stemless ‘true’comatulids,Solanocrinites;the only difference is the presence of a facet to the stem in Copernicrinus.The closest comparable thiolliericrinid to Copernicrinus is the Oxfordian Thiolliericrinus,interpreted as a descendant of the latter.The origin and overview of all thiolliericrinid representatives are also discussed herein.

EXISTENCE AND CONVERGENCE RESULTS FOR AN ELASTIC FRICTIONAL CONTACT PROBLEM WITH NONMONOTONE SUBDIFFERENTIAL BOUNDARY CONDITIONS

The goal of this paper is to study a mathematical model of a nonlinear static frictional contact problem in elasticity with the mixed boundary conditions described by a combination of the Signorini unilateral frictionless contact condition,and nonmonotone multivalued contact,and friction laws of subdifferential form.First,under suitable assumptions,we deliver the weak formulation of the contact model,which is an elliptic system with Lagrange multipliers,and which consists of a hemivariational inequality and a variational inequality.Then,we prove the solvability of the contact problem.Finally,employing the notion of H-convergence of nonlinear elasticity tensors,we provide a result on the convergence of solutions under perturbations which appear in the elasticity operator,body forces,and surface tractions.

Sheltered preservation of cyrtocrinid crinoids from the Lower Cretaceous of Madagascar and their palaeogeographic significance

Sheltered preservation,in which organisms are trapped within shells of cephalopods,is a wellknown phenomenon.This preservational style constitutes an important source of paleontological data.Here,we report the first crinoid preserved inside the early Albian ammonite Cleoniceras besairiei Collignon from Madagascar.This crinoid is assigned to the aspidocrinid phyllocrinid(Apsidocrinus,Phyllocrinidae),and constitutes the first phyllocrinid from the African continent,the second from the southern margin of the Tethys(after New Zealand),and also from the southern hemisphere.This specimen represents the youngest occurrence of a phyllocrinid in the world as well,and constitutes one of the youngest occurrences of cyrtocrinids from shallow sea environments,before predation-induced migration of the stalked crinoids to the deep sea refugia due to the so-called Mesozoic Marine Revolution.This finding highlights that ammonite shells may also be a convenient material for studying echinoderms.

The unexpected occurrence of enigmatic'percevalicrinids'(Echinodermata,Crinoidea)in the Lower Jurassic strata of North Africa—Implications for their stratigraphic and palaeogeographic distribution and discussion on their belonging to the subfamily Balanocrininae

The marl and limestone alternations of the Lower Jurassic Ain Ouarka and Ain Rhezala formations(Pliensbachian-Toarcian)in the western Saharan Atlas,Northwest Algeria,yield a diverse micro-and mac-rofauna,including moderately numerous crinoids,which are represented by remains of isocrinids,i.e.,Bal-anocrinus ticinensis Hess and columnals of the genus Percevalicrinus.So far,the latter genus has been observed from the Upper Jurassic-Lower Cretaceous strata of Eurasia,North America,and the African continent.Thus,the present find is the oldest record of this crinoid genus,and the second one from the southern Tethyan margin.In this paper,it is shown that Percevalicrinus,which is traditionally regarded as a representative of the subfamily Balanocrininae,displays several features of the subfamily Isocrininae.The crinoid assemblage and associated facies and invertebrate fauna are typical of a low-energy deep outer shelf/ramp(below the storm wave-base)setting.

由拟线性反应扩散方程所驱动的非静态不可压缩Navier-Stokes系统

本文考虑一类由非单调多值边界条件的非静态不可压缩Navier-Stokes方程和Neumann边界条件的广义拟线性反应扩散方程所构成的新动力系统,该系统可形式化为非线性抛物方程和发展型H半变分不等式所组成的耦合系统.为获得全局弱解存在性,首先,运用后向Euler法与反馈迭代技术引进耦合系统的时间半离散逼近问题;而后,沿用弱-弱上半连续集值算子的满射定理证明逼近问题解的存在性和先验估计;最后,采用极限过程建立系统全局弱解的存在性定理.