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171.
Mohamed A. El Mubarak Charikleia Danika Charlyne Cachon Charalambia Korovila Korina Atsopardi Nikolaos Panagopoulos Marigoula Margarity Konstantinos Poulas Gregory B. Sivolapenko 《Biomedical chromatography : BMC》2020,34(2):e4752
A sensitive analytical method was developed and validated for the quantification of cotinine in mouse plasma after exposure to smoke of 0.5, 1.0, and 1.5 commercially available cigarettes, using liquid chromatography tandem mass spectrometry. The method was validated over a linear concentration range of 0.075–20.0 ng/mL with the R2 value being higher than 0.99. Both the precision (coefficient of variation; %) and accuracy (relative error; %) were within acceptable criteria of <15%. The lower limit of quantification (LLOQ) for cotinine was 0.075 ng/mL with sufficient specificity, accuracy, and precision. Following exposure to 0.5, 1.0, and 1.5 cigarette smoke, it was observed that the AUC and the Cmax increased linearly as the doses increased. The pharmacokinetics of cotinine was found linear for the range of 0.5–1.5 commercial cigarette smoke. The quantification of the concentration of cotinine in mouse plasma after smoke exposure will facilitate future behavioral and toxicological experiments in animals and may prove useful in predicting cotinine levels in humans during smoking. 相似文献
172.
Positivity - We consider a nonlinear Robin problem associated to the p-Laplacian plus an indefinite potential. In the reaction we have the competing effects of two nonlinear terms. One is... 相似文献
173.
Nikolaos F. Nikitas Mary K. Apostolopoulou Elpida Skolia Anna Tsoukaki Prof. Dr. Christoforos G. Kokotos 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(29):7915-7922
A cheap, facile and metal-free photochemical protocol for the activation of aromatic aldehydes has been developed. Utilizing thioxanthen-9-one as the photocatalyst and cheap household lamps as the light source, a variety of aromatic aldehydes have been activated and subsequently converted in a one-pot reaction into amides, hydroxamic acids and esters in good to high yields. The applicability of this method was highlighted in the synthesis of Moclobemide, a drug against depression and social anxiety. Extended and detailed mechanistic studies have been conducted, in order to determine a plausible mechanism for the reaction. 相似文献
174.
We consider random sets with values in a separable Banach space. We study set-valued amarts, L1-amarts, uniform amarts and submartingales. For all these classes of random sets, we prove convergence theorems in all main modes of set convergence (weak, Wijsman, Mosco, and Hausdorff). We also prove new convergence theorems for vector-valued subpramarts and pramarts. 相似文献
175.
Dimitrios A. Kandilakis Nikolaos S. Papageorgiou 《Proceedings Mathematical Sciences》1998,108(2):179-187
In this paper we examine nonlinear parabolic problems with a discontinuous right hand side. Assuming the existence of an upper
solution φ and a lower solution ψ such that ψ ≤ φ, we establish the existence of a maximum and a minimum solution in the order
interval [ψ, φ]. Our approach does not consider the multivalued interpretation of the problem, but a weak one side “Lipschitz”
condition on the discontinuous term. By employing a fixed point theorem for nondecreasing maps, we prove the existence of
extremal solutions in [ψ, φ for the original single valued version of the problem. 相似文献
176.
Michael E. Filippakis Nikolaos S. Papageorgiou 《Journal of Mathematical Analysis and Applications》2005,311(1):162-181
In this paper we study nonlinear elliptic differential equations driven by the p-Laplacian with unilateral constraints produced by the combined effects of a monotone term and of a nonmonotone term (variational-hemivariational inequality). Our approach is variational and uses the subdifferential theory of nonsmooth functions and the theory of accretive and monotone operators. Also using these ideas and a special choice of the monotone term, we prove the existence of a strictly positive smooth solution for a class of nonlinear equations with nonsmooth potential (hemivariational inequality). 相似文献
177.
Nikolaos S. PAPAGEORGIOU Nikolaos YANNAKAKIS 《数学学报(英文版)》2006,22(1):195-206
We contimle the work initiated in [1] (Second order nonlinear evolution inclusions I: Existence and relaxation results. Acta Mathematics Science, English Series, 21(5), 977-996 (2005)) and study the structural properties of the solution set of second order evolution inclusions which are defined in the analytic framework of the evolution triple. For the convex problem we show that the solution set is compact Rs, while for the nonconvex problem we show that it is path connected, Also we show that the solution set is closed only if the multivalued nonlinearity is convex valued. Finally we illustrate the results by considering a nonlinear hyperbolic problem with discontinuities. 相似文献
178.
In this paper we examine semilinear hemivariational inequalities at resonance at any eigenvalue of the negative Laplacian with Dirichlet boundary condition. Our approach is variational based on the Nonsmooth Critical Point Theory and it uses a generalized Landesman–Lazer condition. We prove two existence theorems using two different forms of the generalized Landesman–Lazer condition. In the last section we show that our Landesman-Lazer condition is more general than the ones existing in the literature. 相似文献
179.
Leszek Gasiński Dumitru Motreanu Nikolaos S. Papageorgiou 《Proceedings Mathematical Sciences》2006,116(2):233-255
We consider a semilinear elliptic equation with a nonsmooth, locally Lipschitz potential function (hemivariational inequality).
Our hypotheses permit double resonance at infinity and at zero (double-double resonance situation). Our approach is based
on the nonsmooth critical point theory for locally Lipschitz functionals and uses an abstract multiplicity result under local
linking and an extension of the Castro-Lazer-Thews reduction method to a nonsmooth setting, which we develop here using tools
from nonsmooth analysis. 相似文献
180.
Yannis Siskos Evangelos Grigoroudis Evangelia Krassadaki Nikolaos Matsatsinis 《European Journal of Operational Research》2007
Employees must acquire new competences and qualifications throughout their lives, in order to be able to deal with the multiple changes in the labour market. The specific knowledge and competences, acquired either formally or non-formally, must be recognized so that they can be transferred and utilized. The existing titles of studies and accreditation mechanisms do not generally cover this need. This paper aims to propose an integrated approach for the evaluation of information technology knowledge and skills, regardless of where and how they have been acquired, so as to apply a continuous education and training policy. The proposed multicriteria methodology for the evaluation of qualifications and skills concerns candidates wishing to be accredited in an information technology specialization or profession. The methodology refers to the evaluation of the professional experience, studies and vocational training of the candidates for accreditation. It contains the analysis and modelling of the qualitative criteria as well as the implementation of multicriteria aggregation–disaggregation techniques attributing value to each criterion. Then, the candidates are classified in categories of professionals using the Electre Tri method, accepting as input data the multicriteria assessments on each criterion. The proposed evaluation approach has been adapted to the Greek educational system and is applied to a specific example of candidate. 相似文献