New Doppler echocardiographic applications for the study of diastolic function

AbstractDoppler echocardiography is one of the most useful clinical tools for the assessment of left ventricular (LV) diastolic function. Doppler indices of LV filling and pulmonary venous (PV) flow are used not only for diagnostic purposes but also for establishing prognosis and evaluating the effect of therapeutic interventions. The utility of these indices is limited, however, by the confounding effects of different physiologic variables such as LV relaxation, compliance and filling pressure. Since alterations in these variables result in changes in Doppler indices of opposite direction, it is often difficult to determine the status of a given variable when a specific Doppler filling pattern is observed. Recently, color M-mode and tissue Doppler have provided useful insights in the study of diastolic function. These new Doppler applications have been shown to provide an accurate estimate of LV relaxation and appear to be relatively insensitive to the effects of preload compensation. This review will focus on the complementary role of color M-mode and tissue Doppler echocardiography and traditional Doppler indices of LV filling and PV flow in the assessment of diastolic function

Model in-cognizant control of residential HVAC units with limited sensing and actuation

In this paper, we consider the problem of controlling residential heating, ventilation and air conditioning (HVAC) units in response to changes in grid-side electrical power imbalances causing unacceptable frequency. We derive a novel energy-based model that relates the HVAC physics-based dynamics to both real and reactive power balance at the point of interconnection with the grid. Based on this modeling, we propose a composite control comprising of a robust sliding mode controller in tandem with a slower model predictive controller that can achieve near-optimal physical and economic performance. In contrast to several other approaches in the literature, we analyze whether a limited number of HVAC units can meet the stringent performance metrics set by the ARPA-E/NODES program on following the regulation signal, while maintaining consumer comfort. Theoretical and simulation-based evidence is provided to show that the proposed approach to control a single HVAC unit results in a provable response simultaneously satisfying NODES program performance metrics and consumer comfort constraints. The use of this model overcomes fundamental issues concerning limited sensor measurements and model uncertainties.Comment: Preprint submitted to IEEE Transactions on Control Systems Technolog

Antígenos del líquido seudocelómico de Ascaris suum detectados por Western Blot utilizando IgY producidos en Gallus gallus var. Hisex Brown

La técnica de Western blot está siendo cada vez más usada en el diagnóstico de enfermedades parasitarias y la búsqueda de fuentes antigénicas para su aplicación constituye un campo de interés creciente. El presente trabajo estuvo orientado a identificar los antígenos en líquido seudocelómico (LS) de Ascaris suum, mediante la técnica de Western Blot utilizando IgY producidos en Gallus gallus. El LS se obtuvo de ejemplares hembras que fueron extraídas directamente del intestino de cerdos naturalmente infectados y sacrificados en el Camal Municipal de El Porvenir (Trujillo, Perú), el cual se utilizó para inmunizar, junto con el adyuvante completo e incompleto de Freud, a un ejemplar de G. gallus Hisex Brown, a fin de obtener  IgY contenida en la yema de huevo. En el LS tratado con dithiothreithol (DTT) se encontró 12 bandas antigénicas, cuyos pesos moleculares fueron: 101.0, 94.9, 65.0, 61.1, 50.6,  45.0, 41.5, 34.6, 22.4, 16.3, 14.4 y 12.7-10.5 KDa; mientras que en el LS no tratado con DTT se encontraron 15 bandas antigénicas, cuyos pesos moleculares fueron: 101.0, 94.9, 65.0, 61.1, 50.6, 45.0, 41.9, 34.6, 27.0, 25.4, 21.5, 18.5, 16.3, 14.4 y 11.2 KDa. Se concluye que el LS de Ascaris suum es una buena fuente de proteínas antigénicas que podrían utilizarse en el diagnóstico de la ascariasis pulmonar.Palabras clave: Ascaris suum, líquido seudocelómico, Western blot

Adiabatic Compression of Soliton Matter Waves

The evolution of atomic solitary waves in Bose-Einstein condensate (BEC) under adiabatic changes of the atomic scattering length is investigated. The variations of amplitude, width, and velocity of soliton are found for both spatial and time adiabatic variations. The possibility to use these variations to compress solitons up to very high local matter densities is shown both in absence and in presence of a parabolic confining potential.Comment: to appear in J.Phys.

Major Phenolics in Yerba Mate Extracts (<i>Ilex paraguariensis</i>) and Their Contribution to the Total Antioxidant Capacity

Yerba mate (Ilex paraguariensis) is an indigenous crop which is highly consumed as an infusion in the South American subtropical forest. It has a high concentration of antioxidant substances, providing health benefits and helping to prevent diseases. The objectives of this work were to characterize an aqueous yerba mate extract by spectrophotometric and chromatographic (HPLC) methods and to study the effect of the freeze-drying process on the polyphenols profile and antioxidant activity, determined by a novel method. An aqueous extract was obtained and lyophilized to obtain a yerba mate powder with antioxidant properties. The extracts showed a high polyphenol content, determined by Folin-Ciocalteau and HPLC, and a high antioxidant activity towards the DPPH· radical and after the recently developed method of photochemiluminescence. A linear correlation was found between Folin-Ciocalteau and DPPH methods for lyophilized samples. HPLC analysis allowed determining antioxidant components like rutin, caffeine and chlorogenic acid. Lyophilization caused a decrease in total polyphenol content and antiradical activity of the extracts and this fact was mainly attributed to changes in the chlorogenic acid related compounds and rutin structures, after their photochemiluminescence data. The photoluminiscent method proves to be an advantageous approach for antioxidant capacity determination.Centro de Investigación y Desarrollo en Criotecnología de AlimentosConsejo Nacional de Investigaciones Científicas y Técnica

Major Phenolics in Yerba Mate Extracts (<i>Ilex paraguariensis</i>) and Their Contribution to the Total Antioxidant Capacity

Yerba mate (Ilex paraguariensis) is an indigenous crop which is highly consumed as an infusion in the South American subtropical forest. It has a high concentration of antioxidant substances, providing health benefits and helping to prevent diseases. The objectives of this work were to characterize an aqueous yerba mate extract by spectrophotometric and chromatographic (HPLC) methods and to study the effect of the freeze-drying process on the polyphenols profile and antioxidant activity, determined by a novel method. An aqueous extract was obtained and lyophilized to obtain a yerba mate powder with antioxidant properties. The extracts showed a high polyphenol content, determined by Folin-Ciocalteau and HPLC, and a high antioxidant activity towards the DPPH· radical and after the recently developed method of photochemiluminescence. A linear correlation was found between Folin-Ciocalteau and DPPH methods for lyophilized samples. HPLC analysis allowed determining antioxidant components like rutin, caffeine and chlorogenic acid. Lyophilization caused a decrease in total polyphenol content and antiradical activity of the extracts and this fact was mainly attributed to changes in the chlorogenic acid related compounds and rutin structures, after their photochemiluminescence data. The photoluminiscent method proves to be an advantageous approach for antioxidant capacity determination.Centro de Investigación y Desarrollo en Criotecnología de AlimentosConsejo Nacional de Investigaciones Científicas y Técnica

Phase ordering in chaotic map lattices with conserved dynamics

Dynamical scaling in a two-dimensional lattice model of chaotic maps, in contact with a thermal bath, is numerically studied. The model here proposed is equivalent to a conserved Ising model with coupligs which fluctuate over the same time scale as spin moves. When couplings fluctuations and thermal fluctuations are both important, this model does not belong to the class of universality of a Langevin equation known as model B; the scaling exponents are continuously varying with the temperature and depend on the map used. The universal behavior of model B is recovered when thermal fluctuations are dominant.Comment: 6 pages, 4 figures. Revised version accepted for publication on Physical Review E as a Rapid Communicatio

Global entrainment of transcriptional systems to periodic inputs

This paper addresses the problem of giving conditions for transcriptional systems to be globally entrained to external periodic inputs. By using contraction theory, a powerful tool from dynamical systems theory, it is shown that certain systems driven by external periodic signals have the property that all solutions converge to a fixed limit cycle. General results are proved, and the properties are verified in the specific case of some models of transcriptional systems. The basic mathematical results needed from contraction theory are proved in the paper, making it self-contained