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The goal of this paper is to present a critique on the incorrect use of the Lipschitz definition concerning the first variable and/or the second variable in the literature on the system of variational inequalities by many authors. The possible impact of this paper is rather important, it questions the results of different authors, particularly when taking into account that some of these papers are published in quite good mathematical journals. As a result, not only that the proofs are wrong, but also the credibility of the theorems themselves is compromised. In addition, this paper illustrate, using a counterexample, that there is an error in setting up first variable definition and the results obtained in listed references do not hold up in H × H.

The goal of this work is demonstrating, through the gradient observation of a of type linear ( -systems), the possibility for reducing the effect of any disturbances (pollution, radiation, infection, etc.) asymptotically, by a suitable choice of related actuators of these systems. Thus, a class of ( -system) was developed based on finite time ( -system). Furthermore, definitions and some properties of this concept -system and asymptotically gradient controllable system ( -controllable) were stated and studied. More precisely, asymptotically gradient efficient actuators ensuring the weak asymptotically gradient compensation system ( -system) of known or unknown disturbances are examined. Consequently, under convenient hypothesis, the existence and the uniqueness of the control of type optimal, guaranteeing the asymptotically gradient compensation system ( -system), are shown and proven. Finally, an approach that leads to a Mathematical approximation algorithm is explored.

The concept of convexity and its various generalizations is important for quantitative and qualitative studies in operations research or applied mathematics. Recently, E-convex sets and functions were introduced with important implications across numerous branches of mathematics. By relaxing the definition of convex sets and functions, a new concept of semi-EE-convex functions was introduced, and its properties are discussed. It has been demonstrated that if a function f:M→Rf:M→R is semi-EE-convex on an EE-convex set M⊂RnM⊂Rn then, f(E(x))≤f(x)f(E(x))≤f(x) for each x∈Mx∈M. This article discusses the inverse of this proposition and presents some results for convex functions.

Althought Malassezia spp. have been involved in various pathologies, they are an integral part of the cutaneous, gut, oral, ears, nose and throat (ENT) mycobiota. Since Malassezia are difficult to grow in culture, unexhaustive molecular biology methods have been developed to detect them. The aim of the study was to evaluate an in-house pan- Malassezia quantitative polymerase chain reaction (panM-qPCR) on various clinical human samples and determine Malassezia burden in various human mycobiota. The panM-qPCR was designed to target the repeated 28S rDNA gene from all Malassezia species. We used the assay to quantify the Malassezia burden on 361 samples from 161 subjects (80 skin swabs from 10 healthy volunteers (HV), 13 samples from 2 seborrheic dermatitis patients (SD), 90 skin samples from 19 burned patients, 119 stool samples from 89 immunocompromised patients, 59 ENT samples from 41 patients). For HV, the amount of Malassezia was different according to the swabbed areas. Quantification cycle (Cq) in SD is lower than in HV. In burned patients, Cq was significantly lower compared to HV. In stool samples, 6.7% were positive for Malassezia spp. with a high Cq. For the ENT area, a higher proportion of positive specimens were detected in ear samples than in nose samples. Our findings emphasized the importance of qPCR, confirming elevated Malassezia spp. levels on individuals' faces and scalps, increased burden in SD patients and in severely burnt patients than in HV. The pan-MqPCR appears to be a promising tool for studying Malassezia in various human mycobiota. [ABSTRACT FROM AUTHOR]

It is well known that convexity theory and its generalization play an important role and have many applications in mathematical programming. In the previous article [2], the authors studied E-convex and semi-E-convex functions. In the present article, we deal with a class of E-quasiconvex functions and give a weak condition for a lower semi-continuous function on ℝn to be an E-quasiconvex function. [ABSTRACT FROM AUTHOR]

In this paper, we show that the results obtained in [7]: On a system of general mixed variational inequalities are incorrect. Also we suggest and analyze new approximation schemes 4.1 for solving the (SGMVID) which were introduced by M.A. Noor in [7]. [ABSTRACT FROM AUTHOR]

We propose a nonsmooth dynamic system integrating production and inventory where the items may deteriorate and the demand is stock-dependent. We aim to derive the optimal production rate. In our first model, backorders are not allowed, while in the second model they are. Using optimal control, necessary optimality conditions are obtained for general forms of the cost, demand, and deterioration rates and closed form solutions are derived for specific forms of these rates. Numerical simulations are presented and sensitivity of the solutions are examined.

Kernel functions play an important role in the complexity analysis of the interior point methods (IPMs) for linear optimization (LO). In this paper, an interior-point algorithm for LO based on a new parametric kernel function is proposed. By means of some simple analysis tools, we prove that the primal-dual interior-point algorithm for solving LO problems meets ..., iteration complexity bound for large-update methods with the special choice of its parameters. [ABSTRACT FROM AUTHOR]

In this paper, we propose a primal–dual interior point method for Linear Complementarity Problem (LCP) based on a new parameterized kernel function. The investigation according to it yields the best-known iteration bound O (n log ⁡ (n) log ⁡ (n ϵ)) for large-update algorithm and thus improves the iteration bound obtained in Bai et al. (SIAM J Optim. 2004;15:101–128) for large-update algorithm. Finally, we present few numerical results to demonstrate the efficiency of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Copyright of Baghdad Science Journal is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Cryptococcal antigen (CrAg) is a capsule polysaccharide antigen that can be detected in the fluids of patients with cryptococcal infections. Cryptococcal Antigen Latex Agglutination System (CALAS), enzyme-linked immunosorbent assays (EIA), and lateral flow assay (LFA) are the main methods available. Two main commercial LFA kits are available: CryptoPS (Biosynex, Illkirch Graffenstaden, France) and CrAg LFA (IMMY, Inc. USA). In our lab, we prospectively used CryptoPS as a screening tool in serum for confirmed positive results with CALAS. We investigated the rigor of the CryptoPS test in serum in a multicentric evaluation over 3 years. To improve the specificity of CryptoPS in serum, we additionally implemented and evaluated a pretreatment protocol before CryptoPS testing. A total of 43 serum samples collected from 43 patients were investigated. We found that the CryptoPS assay is hampered by a high rate of false-positive results in serum with a high rate of CryptoPS-positive but CrAg LFA-negative and CALAS-negative sera in patients with no proof of Cryptococcus infection (n  = 29). Using a simple pretreatment procedure (5 min incubation at 100°C and centrifugation) we were able to reverse false-positive results, suggesting that there could be interferent material present in the serum. Pretreatment also impacted the CryptoPS results (negative result) in two patients with the cryptococcal disease, one with isolated antigenemia and one with cryptococcal meningitis. Comparing the titers obtained with CALAS and CrAg LFA, we noticed that the titer obtained with CrAg LFA was almost 10-fold higher than those with CALAS. This study showed that Biosynex CryptoPS in serum could give false-positive results even in the absence of cryptococcal disease. These could be reduced by applying an easy pretreatment procedure to the serum before testing, with little but existing impact on the sensitivity. [ABSTRACT FROM AUTHOR]

In this paper, we suggest and analyze a new approximation schemes (3) to solve the extended general variational inequalities (2), which were introduced by Muhammad Aslam Noor (see[7, 9]). Using the projection operator technique, we establish the equivalence between the extended general variational inequalities and the fixed-point problem. This equivalent formulation is used to discuss the existence of a solution of the extended general variational inequalities. Several special cases are also discussed. [ABSTRACT FROM AUTHOR]

An early and reliable diagnosis of pregnancy in cows is of considerable economic interest. It would improve the profitability of farmers by reducing the calving-calving interval and avoid any delay of fertilisation which is a cause of significant economic losses. The aim of this study is to evaluate and compare two diagnostic methods of pregnancy in cows after artificial insemination by the assay of the pregnancy-associated proteins (PAGs) and the ultrasonography. The study was carried out on 41 cows aged 3 to 6 years from the Batna region. Blood samples were collected at day (D28) post insemination. This study has shown that among the 41 cows, 25 (60.98%) were pregnant and 16 (39.02%) were not using the transrectal ultrasonography. The sensitivity and the specificity of the PAG assay were 100% and 93.75%, respectively. The specificity was 100% for the ultrasonography, and the embryonic mortalities was 2.43%. The comparative study of the two diagnostic methods of pregnancy has revealed the liability and precocity of the biochemical methods. It is necessary to sensitise inseminators and farmers to the importance of early diagnosis of pregnancy, especially by the use of PAG's assay. It is an essential component of reproduction monitoring and an excellent indicator of early abortions. [ABSTRACT FROM AUTHOR]

The results of a survey made on athletes in body building in Algeries show that the age and the educational level have a big impact on the youth awareness about the effects of dietary supplements on our bodies; we made a survey in Algiers where we asked about one hundred athletes chosen randomly, we came out to the following result: the youth focus on building their bodies no matter what the harms of supplements are. This may be true even with some experienced athletes because the experience is not a determining factor, whereas the age and educational level are very necessary factors. [ABSTRACT FROM AUTHOR]

The numerical simulation of blood flow in arteries using non-Newtonian viscosity model, presents two major difficulties; the first one is the choice of an appropriate constitutive equation, because no one model is universally accepted as a reflection of the true behavior of blood viscosity until now. Another difficulty lies in the numerical convergence of the complex scheme solving the highly non-linear set of equations governing the blood motion. In this paper, the pulsatile blood flow through an arterial stenosis has been numerically modeled to evaluate the flow characteristics and the wall shear stress under physiological conditions. The Navier-Stokes equations governing the fluid motion are solved using the finite element method in unsteady 2-D case. The behavior of blood is considered as the generalized power-law and Cross models, where the shear-thinning characteristics of the streaming blood are taken into account. Constants in the constitutive equations of previous models have been obtained by fitting experimental viscosity data. The numerical simulations are performed for a wide range of apparent shear rates (10 s-1-750 s-1) with good convergence of the iterative scheme. Results from the blood flow simulations indicate that non-Newtonian behavior has considerable effects on instantaneous flow patterns. However, it seems that the generalized power-law model will be slightly better for describing the non-Newtonian characteristics of blood than the Cross model. [ABSTRACT FROM AUTHOR]

The objective of this paper is to study the notion of regional observability of hyperbolic semilinear systems. For the state reconstruction in a given subregion, we give a first approach which combines the extension of the HUM method and the fixed point techniques. The analytical case is then explored using sectorial property of the considered dynamic operator and converted to a fixed point problem. The two approaches lead to algorithms which are successfully implemented numerically and illustrated with examples and simulations. [ABSTRACT FROM PUBLISHER]

Three-dimensional Rayleigh–Bénard instabilities in binary fluids with Soret effect are studied by linear biglobal stability analysis. The fluid is confined transversally in a duct and a longitudinal throughflow may exist or not. A negative separation factor $\psi = \ensuremath{-} 0. 01$, giving rise to oscillatory transitions, has been considered. The numerical dispersion relation associated with this stability problem is obtained with a two-dimensional Chebyshev collocation method. Symmetry considerations are used in the analysis of the results, which allow the classification of the perturbation modes as ${S}_{l} $ modes (those which keep the left–right symmetry) or ${R}_{x} $ modes (those which keep the symmetry of rotation of $\lrm{\pi} $ about the longitudinal mid-axis). Without throughflow, four dominant pairs of travelling transverse modes with finite wavenumbers $k$ have been found. Each pair corresponds to two symmetry degenerate left and right travelling modes which have the same critical Rayleigh number ${\mathit{Ra}}_{c} $. With the increase of the duct aspect ratio $A$, the critical Rayleigh numbers for these four pairs of modes decrease and closely approach the critical value ${\mathit{Ra}}_{c} = 1743. 894$ obtained in a two-dimensional situation, one of the mode (a ${S}_{l} $ mode called mode A) always remaining the dominant mode. Oscillatory longitudinal instabilities ($k\approx 0$) corresponding to either ${S}_{l} $ or ${R}_{x} $ modes have also been found. Their critical curves, globally decreasing, present oscillatory variations when the duct aspect ratio $A$ is increased, associated with an increasing number of longitudinal rolls. When a throughflow is applied, the symmetry degeneracy of the pairs of travelling transverse modes is broken, giving distinct upstream and downstream modes. For small and moderate aspect ratios $A$, the overall critical Rayleigh number in the small Reynolds number range studied is only determined by the upstream transverse mode A. In contrast, for larger aspect ratios as $A= 7$, different modes are successively dominant as the Reynolds number is increased, involving both upstream and downstream transverse modes A and even the longitudinal mode. [ABSTRACT FROM PUBLISHER]

Copyright of Journal of Applied Polymer Science is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A rotating magnetic field (RMF) is used in crystal growth applications during the solidification process in order to improve the crystal quality. Its influence on the convective flows in molten metals and on their stability is studied here in the case of a horizontal infinite cylindrical channel subjected to a longitudinal temperature gradient. The steady convective flows, which correspond to the usual longitudinal counterflow structure, with four vortices in the cross-section for non-zero Prandtl number, Pr, are modified by the RMF (parametrized by the magnetic Taylor number Tam). For zero Prandtl number, the flow in the cross-section corresponds to circular streamlines and the longitudinal flow structure is moved in the direction of the magnetic field rotation, with a decrease in its intensity and an asymptotic variation as 1/Tam. For non-zero Prandtl numbers, depending on the respective values of Tam on one side and Prandtl and Grashof numbers on the other side, different structures ranging from the circular streamlines with transport by rotation of the longitudinal velocity and the temperature field, to the more usual counterflow structure almost insensitive to the RMF with four cross-section vortices, can be obtained. The decrease in the flow intensity with increasing Tam is also delayed for non-zero Pr, but the same asymptotic limit is eventually reached. The stability analysis of these convective flows for Tam = 0 shows a steep increase of the thresholds around Pr = Prt,0 ≈ 3 × 10−4, corresponding to the transition between the usual counterflow shear mode and a new sidewall shear mode. This transition is still present with an RMF, but it occurs for smaller Pr values as Tam is increased. Strong stabilizing effects of the rotating magnetic field are found for Pr < Prt,0, particularly for Pr = 0 where an exponential increase of the threshold with Tam is found. For Pr > Prt,0 (i.e. in the domain where the sidewall instability is dominant), in contrast, the stabilization by the RMF is weak. [ABSTRACT FROM AUTHOR]

Numerical simulations are widely used in polymer processing in order to understand the interaction between the material properties and the process. In the injection moulding process, one of the numerical simulation problems encountered is the tracking of the polymer-air front or interface during the filling stage [1]. In this study, this is achieved by using the classical level set method, which reveals to be conservative. On the contrary, in the case of confined volume of two phases flow, such as an air bubble moving in a constant volume of liquid, the method needs a correction in order to be conservative [2–3]. For a non-Newtonian non-isothermal flow, the simulation involves a coupling between heat transfer, continuity and momentum equations and the rheological material parameters. A finite element method is used to solve this equations set. The results show clearly the expected fountain flow effect. Temperature, velocity, pressure and viscosity fields are calculated and the influence of the thermal contact resistance between the polymer and the mould is presented. [ABSTRACT FROM AUTHOR]