Nutritional habits in heroin addicts

Objetivos: Analizar el estado nutricional y evaluar el consumo alimentario, conocimientos y actitudes en relación con la alimentación en un grupo de adictos a la heroína. Método: Se trata de un estudio observacional analítico basado en registro de valores antropométricos y entrevista alimentaria a los pacientes que realizan un tratamiento de desintoxicación. Resultado: Se observa disminución significativa de la media del índice de masa corporal, horario de comidas irregular, predominio del consumo de dulces, bollería y comida rápida. Conclusiones: La población compuesta por individuos con dependencia a la heroína se encuentra en una situación de elevado riesgo de desarrollo de problemas relacionados con la malnutrición.Objectives: Analyze the nutritional status and evaluate food consumption, knowledge and attitudes in relation to feeding in a group of addicts to the heroine. Method: Record of anthropometric values and food interview to the patients who realize a treatment of detoxification. Results: Significant decrease of the mean body mass index, irregular meal times, dominance of sweets, pastries and fast-food consumption. Conclusions: The population of individuals with heroin dependence is in a situation of high risk of developing problems associated with malnutrition

Collective Coordinates Theory for Discrete Soliton Ratchets in the sine-Gordon Model

A collective coordinate theory is develop for soliton ratchets in the damped discrete sine-Gordon model driven by a biharmonic force. An ansatz with two collective coordinates, namely the center and the width of the soliton, is assumed as an approximated solution of the discrete non-linear equation. The evolution of these two collective coordinates, obtained by means of the Generalized Travelling Wave Method, explains the mechanism underlying the soliton ratchet and captures qualitatively all the main features of this phenomenon. The theory accounts for the existence of a non-zero depinning threshold, the non-sinusoidal behaviour of the average velocity as a function of the difference phase between the harmonics of the driver, the non-monotonic dependence of the average velocity on the damping and the existence of non-transporting regimes beyond the depinning threshold. In particular it provides a good description of the intriguing and complex pattern of subspaces corresponding to different dynamical regimes in parameter space

Anomalous resonance phenomena of solitary waves with internal modes

We investigate the non-parametric, pure ac driven dynamics of nonlinear Klein-Gordon solitary waves having an internal mode of frequency $\Omega_i$. We show that the strongest resonance arises when the driving frequency $\delta=\Omega_i/2$, whereas when $\delta=\Omega_i$ the resonance is weaker, disappearing for nonzero damping. At resonance, the dynamics of the kink center of mass becomes chaotic. As we identify the resonance mechanism as an {\em indirect} coupling to the internal mode due to its symmetry, we expect similar results for other systems.Comment: 4 pages, 4 figures, to appear in Phys Rev Let

On the existence of internal modes of sine-Gordon kinks

We study whether or not sine-Gordon kinks exhibit internal modes or ``quasimodes.'' By considering the response of the kinks to ac forces and initial distortions, we show that neither intrinsic internal modes nor ``quasimodes'' exist in contrast to previous reports. However, we do identify a different kind of internal mode bifurcating from the bottom edge of the phonon band which arises from the discretization of the system in the numerical simulations, thus confirming recent predictions.Comment: 4 pages, 2 figures, REVTeX, to appear as a Rapid Communication in Phys Rev E (July 1st

Overdamped sine-Gordon kink in a thermal bath

We study the sine-Gordon kink diffusion at finite temperature in the overdamped limit. By means of a general perturbative approach, we calculate the first- and second-order (in temperature) contributions to the diffusion coefficient. We compare our analytical predictions with numerical simulations. The good agreement allows us to conclude that, up to temperatures where kink-antikink nucleation processes cannot be neglected, a diffusion constant linear and quadratic in temperature gives a very accurate description of the diffusive motion of the kink. The quadratic temperature dependence is shown to stem from the interaction with the phonons. In addition, we calculate and compute the average value $$ of the wave function as a function of time and show that its width grows with $\sqrt{t}$. We discuss the interpretation of this finding and show that it arises from the dispersion of the kink center positions of individual realizations which all keep their width.Comment: REVTeX, 12 pages, 10 figures, to appear in Phys Rev

Polarografía de complejos de ácido acetilsalicílico con Zn(II)

Se ha realizado un estudio polarográfico de complejos del ácido acetilsalicílico con Zn(II) en Clk 1 M (ph = 6,5). El proceso de reducción del catión metálico es analizado por medidas polarográficas convencionales y oscilopolarográficas. Se han calculado los valores de las constantes de formación de los complejos (ASA) Zn + y (ASA)2 Zn.Polarographic waves of Zn(II) and acetysalicylic acid Zn(lI) complexes in CIK 1 M (ph = 6,5) are reported. Electrochemical reduction of metallic cation has been analyzed by means conventional and oscilopolarographic methods. The formation constants of comple.xes (ASA)Zn + and (ASA)z Zn have been calculated

Polarografía de complejos de ácido acetilsalicílico con Zn(II)

Polarographic waves of Zn(II) and acetysalicylic acid Zn(II) complexes in CIK 1 M (ph = 6,5) are reported. Electrochemical reduction of metallic cation has been analyzed by means conventional and oscilopolarographic methods. The formation constants of comple.xes (ASA)Zn + and (ASA)2 Zn have been calculated.Se ha realizado un estudio polarográfico de complejos del ácido acetilsalicílico con Zn(II) en Clk 1 M (ph = 6,5). El proceso de reducción del catión metálico es analizado por medidas polarográficas convencionales y oscilopolarográficas. Se han calculado los valores de las constantes de formación de los complejos (ASA) Zn + y (ASA)2 Zn

Una experiencia de enseñanza en la red en la Universidad de Murcia

En el presente trabajo pretendemos presentar la experiencia de diseñar por primera vez una asignatura para ser seguida enteramente a través de la red en el entorno de la Universidad Presencial.Eje: Educación universitaria: Experiencias uso NTICRed de Universidades con Carreras en Informática (RedUNCI

Determinación potenciométrica del PKa del grupo fenólico en el N-Acetilderivado del 1-(3-Hidroxifenil)-2-(N-Metilamino)Etanol

Values of the dissociation constant of the phenolic group in the N-acetilated derivative of 1 -(3-hydroxyphenyl)-2-(N-methylamine)ethanol have been calculated at different ionic strengths. The results found are: pKa = 9,49 (I = 0,3); pKa = 9,50 (I = 0,1); pKa = 9,55 (I = 0,04) and pKa.= 9,57 (I = 0,02).Se ha determinado el valor de la constante de disociación del grupo fenólico en el N-acetilderivado del 1-(3-hidrofenil( -2-(N-metilamino )etanol por técnica potenciométrica a diferentes fuerzas iónicas. Los valores encontrados fueron los siguientes: pKa = 9,49 (I = 0,3); pKa = 9,50 (I = 0,1); pKa = 9,55 (I = 0,04) y pKa = 9,57 (I = 0,02)

Una experiencia de enseñanza en la red en la Universidad de Murcia

En el presente trabajo pretendemos presentar la experiencia de diseñar por primera vez una asignatura para ser seguida enteramente a través de la red en el entorno de la Universidad Presencial.Eje: Educación universitaria: Experiencias uso NTICRed de Universidades con Carreras en Informática (RedUNCI