Integral representations for a generalized Hermite linear functional

In this paper we find new integral representations for the {\it generalized Hermite linear functional} in the real line and the complex plane. As application, new integral representations for the Euler Gamma function are given.Comment: 4 figure

New eco-coatings based on natural dyes and aqueous polyurethane dispersions

At present, there are an increasing interest at industrial level by the N-methyl pyrrolidone (NMP) free polyurethane aqueous dispersion, due to the limitations posed to this solvent in the latest years in Europe. Among the several applications of coatings, the protection and decoration of objects is one of the most used. Decoration requires color control and new ways to generate long-lasting colors. However, these products are traditionally based on synthetic dyes, which have a lack of compatibility with the aqueous medium resulting in phase separation or agglomerations phenomena. Herein, the use of hydrophilic natural dyes can be envisaged as a viable alternative, once these dyes nature increases their compatibility with the aqueous medium, leading to the increasing of the final product stability along the time. In this context, the present work was devoted to the development of new eco-coatings based on natural dyes and in polyurethanes aqueous dispersions exempt of NMP. For this study, a polyurethane aqueous dispersion based on isophorone diisocyanate and propylene glycol polyol was synthesized. After, the dispersion properties like solids content, viscosity, pH and particle size were evaluated. Then, coatings added with carminic acid and spirulina blue dyes were produced by solvent casting, by incorporating dyes contents of 0.2, 0.5, 1.0, 1.5 and 2.0% (w/w) into the dispersion. The films obtained after drying were characterized in terms of chemical structure by Fourier Transform Infrared Spectroscopy, which showed the lack of influence of the dyes chemical structure on the polyurethane films, even for the higher content tested. Differential Scanning Calorimetry evidenced the effect of the dye on the films thermal behavior, once when 2% of dyes were added, the values of melting temperature (Tm) and the melting enthalpy variation (ΔHm) increased for values higher than the base film. Thermogravimetric Analysis showed an increase of the film’s thermal stability as the dyes content was increased. The colorimetric analysis was made in order to inspect the color variation due to the dye type and content used. By comparing the base film color with the dyed films, an increasing on the color variation was detected for both dyes. However, for the films containing Spirulina blue this increased with the dye content rising, reaching a maximum value of 65.58 for 2%Sp. In opposition, for carminic acid, the color variation reached a maximum value of 70.62 for 1.0%Cr, being constant for the higher dye contents. In a general way this study evidences the positive effect of the utilization of natural dyes together with friendly polyurethane aqueous dispersions for the production of innovative coatings.Atualmente, a nível industrial regista-se um interesse crescente na utilização de dispersões aquosas de poliuretano isentas de N-metil pirrolidona (NMP), devido às limitações impostas a este solvente na Europa, nos últimos anos. Entre as diversas aplicações dos revestimentos, a proteção e decoração de objetos é uma das mais utilizadas. A decoração requer o controlo das cores e novas formas de gerar cores duradouras. No entanto, estes produtos são tradicionalmente baseados em corantes sintéticos, os quais apresentam falta de compatibilidade com o meio aquoso, resultando em fenómenos de separação de fases ou de aglomeração. Neste contexto, o uso de corantes naturais hidrofílicos pode ser considerado como uma alternativa viável, uma vez que a natureza destes aumenta a sua compatibilidade com o meio aquoso, incrementando a estabilidade do produto final ao longo do tempo. Neste contexto, o presente trabalho foi dedicado ao desenvolvimento de novos eco-revestimentos baseados em corantes naturais e em dispersões aquosas de poliuretanos isentas de NMP. Neste estudo, procedeu-se à síntese de uma dispersão aquosa de poliuretano baseada em diisocianato de isoforona e propilenoglicol. Seguidamente avaliaram-se as seguintes propriedades da dispersão: teor de sólidos, viscosidade, pH e tamanho de partícula. Na etapa seguinte produziram-se filmes base (sem corantes) e modificados através a adição dos corantes ácido carmínico e azul da spirulina, pelo método de solvente casting, incorporando os seguintes teores 0,2, 0,5, 1,0, 1,5 e 2,0 % (m/m). Os filmes obtidos após a secagem foram caracterizados em termos de estrutura química por Espectroscopia de Infravermelho com Transformada de Fourier, que mostrou a ausência de contribuições da estrutura química dos corantes nos filmes do poliuretano, mesmo para o maior teor testado. Através da Differential Scanning Calorimetry verificou-se que o efeito do corante no comportamento térmico dos filmes resultou no incremento de temperatura de fusão (Tm) e entalpia de fusão (ΔHm), dado que quando se incorporou 2% dos corantes estes aumentaram para valores superiores aos obtidos para o filme base. A análise termogravimétrica mostrou um aumento da estabilidade térmica dos filmes com o incremento do teor de corantes. Através da análise colorimétrica avaliou-se a variação de cor devido ao tipo de corante e ao teor utilizado. Ao comparar a cor dos filme de base com a dos filmes modificados com o corante, verificou-se um aumento da variação de cor, para os dois corantes testados. No entanto, para os filmes contendo azul da spirulina, esta variação aumentou com o incremento do teor do corante, atingindo um valor máximo de 65,58 para a amostra 2% Sp. Em oposição, para o ácido carmínico, a variação de cor atinge um valor máximo de 70,62 para 1,0% de Cr, sendo constante para os teores mais elevados.This work was financially supported by Associate Laboratory LSRE-LCM (UID/EQU/50020/2019) funded by national funds through FCT/MCTES (PIDDAC), and Foundation for Science and Technology (FCT, Portugal). CIMO (UID/AGR/00690/2019) through FEDER under Program PT2020

Choice of the Exchange Policies in the Developments Countries: Study of the Competitiveness of Tunisia

After the collapse of the Breton Woods system, the increased fluctuations of the exchange rates pushed the developing countries to adopt exchange rate policies to avoid rocking of the balance of payments. Since 1973, Tunisia adopted fixed or intermediary exchange rate policies to support or ameliorate her competitiveness and later to balance her current account. By calculating the real effective exchange rate misalignment, we showed that this country did not achieve her goals and that amelioration of competitiveness occurred only as from the moment when she softened her exchange policies. A policy of floating exchange rate is recommended for Tunisia especially why this country is more and more open.Exchange policy, Real effective exchange rate misalignment, Competitiveness, Tunisia

Exchange Policy and Economic Growth: Effect of the Real Effective Exchange Rate Misalignment on the Growth of Tunisia

The collapse of the system of Bretton Woods pushed Tunisia adopted various policies of exchange to avoid imbalances of the balance of payments. Since, this country aimed to maintain or to improve its external competitiveness in order to balance its current account through the promotion of exports, this contribute to start again the economic growth. By specifying an equation of economic growth of Tunisia, it’s showed that the real effective exchange rate misalignment, indicator of external competitiveness, has negative effect on the economic growth. The fall of real effective exchange rate misalignment, these last years, then explained partly the stabilization of the growth rate of this country can especially since 2001 when the Tunisia softened its policy of exchange rate. A flexible policy of exchange is then desirable to start again the economic growth

Nonexistence Results of Solutions of Semilinear Differential Inequalities with Temperal Fractional Derivative on the Heinsenberg Group

2000 Mathematics Subject Classification: 26A33, 33C60, 44A15, 35K55Denoting by Dα0|t the time-fractional derivative of order α (α ∈ (0, 1)) in the sense of Caputo, and by ∆H the Laplacian operator on the (2N + 1) - dimensional Heisenberg group H^N, we prove some nonexistence results for solutions to problems of the type Dα0|tu − ∆H(au) >= |u|^p, Dα0|tu − ∆H(au) >= |v|^p, Dδ0|tv − ∆H(bv) >= |u|^q, in H^N × R+ , with a, b ∈ L ∞ (H^N × R+). For α = 1 (and δ = 1 in the case of two inequalities), we retrieve the results obtained by Pohozaev-Véron [10] and El Hamidi-Kirane [3] corresponding, respectively, to the parabolic inequalities and parabolic system

Second structure relation for semiclassical orthogonal polynomials

18 pages, no figures.-- MSC2000 codes: 42C05; 33C45.MR#: MR2289233 (2009a:33013)Zbl#: Zbl 1125.33008Classical orthogonal polynomials are characterized from their orthogonality and by a first or second structure relation. For the semiclassical orthogonal polynomials (a generalization of the classical ones), we find only the first structure relation in the literature. In this paper, we establish a second structure relation. In particular, we deduce it by means of a general finite-type relation between a semiclassical polynomial sequence and the sequence of its monic derivatives.The work of the first author (F. M.) was supported by Dirección General de Investigación (Ministerio de Educación y Ciencia) of Spain under Grant BFM 2003-06335-C03-02 and INTAS Research Network NeCCA INTAS 03-51-6637. The second author (R. S.) was supported by Entreprise Kilani Gabès and Faculté des Sciences de Gabès, Tunisie.Publicad

Spectroscopic ellipsometry study of barrier width effect in self-organized InGaAs/GaAs QDs laser diodes

Molecular beam epitaxy (MBE) is used to grow InGaAs/GaAs quantum dots (QDs) laser diodes (LDs) with different barrier widths (5, 10 and 15 nm) at 580 ºC on GaAs substrates. Optical properties of the InGaAs/GaAs QDs LDs have been investigated by using the spectroscopic ellipsometry (SE) technique. A general oscillator optical model has been utilized to fit the experimental data in order to obtain the LD layer thicknesses, refractive index and absorption coefficient. The dielectric function, the energy band gap and the surface and volume energy loss functions are computed in the energy range 1-6 eV. The optical properties of the deposited InGaAs/GaAs QDs LDs are found to be affected by the barrier width, which give more insight into carriers dynamics and optical parameters in these devices. The refractive indices, the extinction coefficients and the dielectric constants of the LDs with barrier widths 15 and 10 nm are relatively larger than those of the LD with barrier width 5 nm. These indicate that optical properties of LDs with larger barrier widths (15 and 10 nm) will be improved. The interband transition energies in the three devices have calculated and identified. Two energy gaps at 1.04 and ~1.37 eV are obtained for all the heterostructures which indicates that fabricated LDs may be operating for a wavelength of 1.23 m at room temperature

Application de la méthode MASW pour la détection de zones de faiblesse sous les chaussées

Le but de ce document est d'appliquer une méthode entièrement développée à l'Université de Sherbrooke appelée Modal-Analysis-of-Surface-Waves (MASW) afin de détecter les zones de faiblesses sur les structures de chaussées telles que les cavités causées par infiltration de sol dans les vieux ponceaux par exemple. Cette méthode d'investigation sismique utilise l'enregistrement rapide des ondes de surface comme base de données. À partir d'essais in-situ non intrusifs, la méthode permet d'obtenir un profil des ondes de cisaillement en fonction de la profondeur. La première partie est consacrée à l'état des connaissances sur les ondes et les différentes méthodes géophysiques de caractérisation des pavages. Elle comprend la théorie de propagation des différentes ondes (compression, cisaillement et de surface); les modèles théoriques de calcul de la vitesse des ondes de cisaillement pour les sols granulaires et argileux; les différentes méthodes sismiques présentement utilisées sur les pavages en ingénierie. La deuxième partie explique de façon approfondie la méthode MASW: son historique, l'équipement nécessaire et le cheminement typique d'un essai. Elle présente aussi une nouvelle configuration pour la méthode MASW afin de mieux l'adapter à la reconnaissance des structures des chaussées. Il s'agit d'une excitation à côté du pavage au lieu du dessus. La troisième partie résume les résultats de différentes études numériques visant d'abord à minimiser au maximum l'effet de la couche de pavage sur le profil de vitesses des ondes de cisaillement des couches inférieures et ensuite à détecter et à localiser la présence de zones de faiblesse. Une correction de la courbe de dispersion a été envisagée permettant de réduire l'effet de la couche de pavage sur les couches sous-jacentes. Enfin, la quatrième partie présente les résultats obtenus pour deux sites ayant fait l'objet d'une reconnaissance avec la méthode MASW sur les structures de chaussée

Oxidative stress and lung function profiles of male smokers free from COPD compared to those with COPD: A case-control study

Background: The mechanisms of smoking tobacco leading to chronic obstructive pulmonary disease (COPD) are beginning to be understood. However, conclusions about the role of blood or lung oxidative stressmarkers were disparate.Aims: To investigate the oxidative stress in blood or lung associated with tobacco smoke and to evaluate its effect on pulmonary function data and its relation with physical activity.Methods: It is a case-control study. Fifty-four male-smokers of more than five pack-years (PY) and aged 4060 years were included (29 Non-COPD, 16 COPD). Physical activity score was determined. Blood sample levels of malondialdehyde (MDA), protein-cys-SH (PSH), and Glutathione (GSH) were measured. Fractional exhaled nitric oxide (FeNO) and plethysmographic measurements were performed. Correlation coefficients (r) evaluated the association between oxidative stress markers and independent variables (plethysmographic data and physical activity score).Results: Non-COPD (4896 years) and COPD (4995 years) groups had  similar tobacco consumption patterns, that is, 27914 PY versus 30919 PY, respectively. Compared to the Non-COPD group, the COPD group had significantly lower levels of GSH and PSH, that is, mean9SE were 4096 versus 2595 mg/mL and 54910 versus 2695 mg/g of hemoglobin,  respectively. However, MDA level and FeNO values were similar. In the COPD group, none of the oxidative stress markers was significantly  correlated with plethysmographic data or physical activity score. In the Non-COPD group, GSH was significantly correlated with physical activity score (r0.47) and PSH was significantly correlated with total lung capacity (TLC) (r0.50), residual volume (r0.41), and physical activity score (r0.62). FeNO was significantly correlated with TLC of the COPD group (r0.48).Conclusion: Compared to the Non-COPD group, the COPD group had a marked decrease in blood antioxidant markers (GSH and PSH) but similar blood oxidant (MDA) or lung (FeNO) burden.Keywords: inflammation; lung disease; spirometry; tobacco; sedentarily; stress oxidan

Necessary conditions for local and global existence to a reaction-diffusion system with fractional derivatives

We give some necessary conditions for local and global existence of a solution to reaction-diffusion system of type (FDS) with temporal and spacial fractional derivatives. As in the case of single equation of type (STFE) studied by M. Kirane et al. (2005), we prove that these conditions depend on the behavior of initial conditions for large |x|