166 research outputs found

    Influence of Chemical Enhancers and Iontophoresis on the In Vitro Transdermal Permeation of Propranolol: Evaluation by Dermatopharmacokinetics

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    [EN] The aims of this study were to assess, in vitro, the possibility of administering propranolol transdermally and to evaluate the usefulness of the dermatopharmacokinetic (DPK) method in assessing the transport of drugs through stratum corneum, using propranolol as a model compound. Four chemical enhancers (decenoic and oleic acid, laurocapram, and R-(+)-limonene) and iontophoresis at two current densities, 0.25 and 0.5 mA/cm(2) were tested. R-(+)-limonene, and iontophoresis at 0.5 mA/cm(2) were proven to be the most efficient in increasing propranolol transdermal flux, both doubled the original propranolol transdermal flux. Iontophoresis was demonstrated to be superior than the chemical enhancer because it allowed faster delivery of the drug. The DPK method was sufficiently sensitive to detect subtle vehicle-induced effects on the skin permeation of propranolol. The shorter duration of these experiments and their ability to provide mechanistic information about partition between vehicle and skin and diffusivity through skin place them as practical and potentially insightful approach to quantify and, ultimately, optimize topical bioavailability.This research was funded by Ministerio de Ciencia e Innovación (AP2007-03456) and the Universidad CEU Cardenal Herrera.Calatayud-Pascual, M.; Sebastian-Morelló, M.; Balaguer-Fernandez, C.; Delgado-Charro, M.; Lopez-Castellano, A.; Merino Sanjuán, V. (2018). Influence of Chemical Enhancers and Iontophoresis on the In Vitro Transdermal Permeation of Propranolol: Evaluation by Dermatopharmacokinetics. Pharmaceutics. 10(4):1-15. https://doi.org/10.3390/pharmaceutics10040265S11510

    Renormalization group study of one-dimensional systems with roughening transitions

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    A recently introduced real space renormalization group technique, developed for the analysis of processes in the Kardar-Parisi-Zhang universality class, is generalized and tested by applying it to a different family of surface growth processes. In particular, we consider a growth model exhibiting a rich phenomenology even in one dimension. It has four different phases and a directed percolation related roughening transition. The renormalization method reproduces extremely well all the phase diagram, the roughness exponents in all the phases and the separatrix among them. This proves the versatility of the method and elucidates interesting physical mechanisms.Comment: Submitted to Phys. Rev.

    Recent results on multiplicative noise

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    Recent developments in the analysis of Langevin equations with multiplicative noise (MN) are reported. In particular, we: (i) present numerical simulations in three dimensions showing that the MN equation exhibits, like the Kardar-Parisi-Zhang (KPZ) equation both a weak coupling fixed point and a strong coupling phase, supporting the proposed relation between MN and KPZ; (ii) present dimensional, and mean field analysis of the MN equation to compute critical exponents; (iii) show that the phenomenon of the noise induced ordering transition associated with the MN equation appears only in the Stratonovich representation and not in the Ito one, and (iv) report the presence of a new first-order like phase transition at zero spatial coupling, supporting the fact that this is the minimum model for noise induced ordering transitions.Comment: Some improvements respect to the first versio

    High dimensional behavior of the Kardar-Parisi-Zhang growth dynamics

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    We investigate analytically the large dimensional behavior of the Kardar-Parisi-Zhang (KPZ) dynamics of surface growth using a recently proposed non-perturbative renormalization for self-affine surface dynamics. Within this framework, we show that the roughness exponent α\alpha decays not faster than α1/d\alpha\sim 1/d for large dd. This implies the absence of a finite upper critical dimension.Comment: RevTeX, 4 pages, 2 figures. To appear in Phys. Rev.

    A numerical study of the development of bulk scale-free structures upon growth of self-affine aggregates

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    During the last decade, self-affine geometrical properties of many growing aggregates, originated in a wide variety of processes, have been well characterized. However, little progress has been achieved in the search of a unified description of the underlying dynamics. Extensive numerical evidence has been given showing that the bulk of aggregates formed upon ballistic aggregation and random deposition with surface relaxation processes can be broken down into a set of infinite scale invariant structures called "trees". These two types of aggregates have been selected because it has been established that they belong to different universality classes: those of Kardar-Parisi-Zhang and Edward-Wilkinson, respectively. Exponents describing the spatial and temporal scale invariance of the trees can be related to the classical exponents describing the self-affine nature of the growing interface. Furthermore, those exponents allows us to distinguish either the compact or non-compact nature of the growing trees. Therefore, the measurement of the statistic of the process of growing trees may become a useful experimental technique for the evaluation of the self-affine properties of some aggregates.Comment: 19 pages, 5 figures, accepted for publication in Phys.Rev.

    Use of low-resolution CT scans for construction of detailed geometric models of mandibles with and without teeth

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    Detailed geometric models of a mandible can improve the accuracy of computer simulations. However, cost, time and qualified labor available for their construction may hinder or delay the task. The purpose of this article is to describe a technique for reconstructing a mandible with and without teeth from clinical CT scans of low resolution. The method allows modeling geometric details usually difficult to reconstruct with these scans, such as the periodontal ligament. The models of a toothless and toothed mandible resulting from the process are available online for non-commercial use. The models can be used in various fields such as orthodontics, implantology, orthopedics and traumatology as presented or as a basis for simulations

    Consensus and ordering in language dynamics

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    We consider two social consensus models, the AB-model and the Naming Game restricted to two conventions, which describe a population of interacting agents that can be in either of two equivalent states (A or B) or in a third mixed (AB) state. Proposed in the context of language competition and emergence, the AB state was associated with bilingualism and synonymy respectively. We show that the two models are equivalent in the mean field approximation, though the differences at the microscopic level have non-trivial consequences. To point them out, we investigate an extension of these dynamics in which confidence/trust is considered, focusing on the case of an underlying fully connected graph, and we show that the consensus-polarization phase transition taking place in the Naming Game is not observed in the AB model. We then consider the interface motion in regular lattices. Qualitatively, both models show the same behavior: a diffusive interface motion in a one-dimensional lattice, and a curvature driven dynamics with diffusing stripe-like metastable states in a two-dimensional one. However, in comparison to the Naming Game, the AB-model dynamics is shown to slow down the diffusion of such configurations.Comment: 7 pages, 6 figure

    Misure di radioattività naturale nel sito preistorico di Grotta dei Cervi in Porto Badisco (LE)

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    Nel presente lavoro sono riportati I risultati di una campagna di misure finalizzata alle determinazione della concentrazione di radon all’interno di Grotta dei Cervi di Porto Badisco (LE). Grotta dei Cervi è una cavità carsica caratterizzata da un complesso pittorico neolitico imponente

    Implementation of Classroom of Pharmacy at the Faculty of Health Sciences

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    El Espacio Europeo de Educación Superior (EEES) supone un cambio en nuestras metodologías docentes, que deben orientarse hacia una mayor participación del alumno en el proceso de enseñanzaaprendizaje, así como a satisfacer la necesidad de formación del mundo laboral. Por ello, y en base a la necesidad de nuestra Universidad de adaptar la docencia de Farmacia al Espacio Europeo de Educación Superior, la Facultad de Ciencias de la Salud de la Universidad CEU Cardenal Herrera, ha desarrollado un proyecto para implantar un aula que simule una Oficina de Farmacia. Entre los perfiles laborales del farmacéutico, el de Oficina de Farmacia es el más frecuente, por ser esta la ocupación laboral mayoritaria. La labor en las farmacias comunitarias consiste básicamente en la conservación, dispensación, asesoramiento y elaboración de medicamentos. Todo ello, unido al ejercicio de la atención farmacéutica, conlleva una gran carga de responsabilidad, un conocimiento y vigilancia de la legislación establecida al respecto y una base científica y técnica importante. La farmacia es, a su vez, un centro de educación y prevención sanitaria, dietética y cosmética. Con el objetivo de que nuestros alumnos desarrollen todas las competencias necesarias para el farmacéutico en la Facultad de Salud se implantó el Aula de la Farmacia.The European Higher Education Area (EHEA) represents a shift in our teaching methodology, which should now be steered towards a greater participation of students in the teaching-learning process and should satisfy the employment market’s need for trained professionals. In this context, our university has sought to adapt its pharmacy teaching programme to the EHEA, and so the Faculty of Health Sciences of the CEU Cardenal Herrera University has developed a project to create a space that simulates a working pharmacy. Among the different professional profiles within the discipline of pharmacy, a position in a chemist’s/drugstore is the most common, as the majority of pharmacists are employed as such. The work of community pharmacies basically consists of the storing, dispensing and preparation of medication. These tasks, combined with the pharmaceutical care provided to patients and customers, involve a great deal of responsibility that depends on knowledge and safeguarding of the current legislation and a solid scientific and technical training. A pharmacy is, at the same time, a centre of education and prevention in health, diet and cosmetics. With all of this in mind, the Pharmacy Room was created by the Health Sciences Faculty with the objective of allowing our students to develop all the skills expected of a pharmacist

    A Biased Review of Sociophysics

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    Various aspects of recent sociophysics research are shortly reviewed: Schelling model as an example for lack of interdisciplinary cooperation, opinion dynamics, combat, and citation statistics as an example for strong interdisciplinarity.Comment: 16 pages for J. Stat. Phys. including 2 figures and numerous reference
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