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This paper presents the design of a tuned mass damper (TMD) for vibration control of a simply supported metal beam. Considering the mechanical properties of commercial springs and magnetic dampers, and applying the finite element method, the feasibility of couple a TMD that allow to reduce vibrations in the beam was evaluated. This paper describes the beam mechanical properties, as well as the characteristics of the tuned mass damper. These results can be used in construction of dynamic models that promote the experimental study of structures. The equations proposed by Deng Hartog were used to identify adequate stiffness and damping. Finally, it was evaluated the performance of the TMD in vibration control under impact excitation conditions. With the implementation of this device, were obtained reductions of more than 90%. [ABSTRACT FROM AUTHOR]

Copyright of Archivos de Zootecnia is the property of Archivos de Zootecnia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of MEDISAN is the property of Centro Provincial de Informacion en Ciencias Medicas de Santiago de Cuba and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The work was carried out to know the yield response of sugarcane depending on the stock and nutrition in three long term experiments conducted from 1978 to 2007 in a typical red Ferralitic soil, for the study of nitrogen (N), phosphorus (P) and potassium (K) doses, in the province of Ciego de Ávila, Cuba. Each of the experiments had 23 harvests. In the three experiments, the plant cane stock did not increase the yield with N and K applications and there was only a positive effect of phosphoric fertilization in 40% of them. Also, the set consisting of plant cane, first and second sprouts responded to N and K in 15 and 23%, respectively, reaching 54% in the case of the study of P. On the contrary, from the third sprout and up the sixth, responses were found in 100%, 90% and 80% of the harvests made in the experiments of N, P and K, respectively, associated with the worsening of soil conditions, stock aging and difficulty of root system to reach nutrients. [ABSTRACT FROM AUTHOR]

The main characteristics of the Public Health Sphere in Santiago de Cuba province are described, specifically those related to the following aspects: structure, associate specialists, net of relationships, activities carried out, current problems, as well as drawn up strategy at short and medium term, which will allow to give solution to the problems that can be presented. [ABSTRACT FROM AUTHOR]

Copyright of Revista Avances: Investigación en Ingeniería is the property of Universidad Libre, Facultad de Ingenieria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Comunicación is the property of Universidad Pontificia Bolivariana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ginecología y Obstetricia de México is the property of Federacion Mexicana de Ginecologia y Obstetricia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Innovación Tecnológica is the property of Instituto de Informacion Cientifica y Tecnologica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Cirugía Plástica Ibero-Latinoamericana is the property of Cirugia Plastica Ibero-Latinoamericana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A descriptive and longitudinal study was conducted in 32039 patients under 5 years with acute respiratory infections, discharged from Southern Children Teaching Hospital of Santiago de Cuba, from January 1997 to December 2010, to characterize the morbidity from these infections in those affected. Among the analyzed variables were age, sex, types of acute respiratory infections, and epidemiological factors that predispose to morbidity or death due to pneumonia, microbiological studies and morbidity rates from acute respiratory infections. Upper airways infections, patients aged 2 months to 4 years and male sex prevailed as well as anemia, poor breastfeeding practices, previous use of antimicrobials and teenage mothers. Prevalence rates showed little annual variability during the decade consistent with gross morbidity. [ABSTRACT FROM AUTHOR]

Copyright of Revista Chilena de Pediatría is the property of Revista Chilena de Pediatria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Chilena de Obstetricia y Ginecología is the property of Revista Chilena de Obstetricia y Ginecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Lower extremity defects, specially lower third defects, keep being a true challenge in Reconstructive Surgery, since nearness damaged tissues, due to the traumatism or to the concomitant edema, are not suitable for the coverage of bone, tendons or exposed osteosynthesis material. Propeller flap has become an elegant and mobile method for the coverage of this type of lower extremity defects. It provides us with locorregional tissue with no vascular involvement in the traumatism and/or subsequent injury. Unlike conventional rotation or transposition flaps, direct closure of the donor site is possible, offering an optimum aesthetic result. Moreover, the presence of more proximal perforators allows the use of muscular and tendinous cuffs in the same flap to solve more complex defects, becoming something more than a free flap alternative. We present a serie of 43 patients to describe the reconstructive possibilities of the tibialis posterior perforator flap in its propeller form, as for design variability and composed flap use, with the aim of minimizing donor site morbility even more without the use of grafts. [ABSTRACT FROM AUTHOR]

Copyright of Ginecología y Obstetricia de México is the property of Federacion Mexicana de Ginecologia y Obstetricia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Cirugía Plástica Ibero-Latinoamericana is the property of Cirugia Plastica Ibero-Latinoamericana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Chilena de Obstetricia y Ginecología is the property of Revista Chilena de Obstetricia y Ginecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

El artículo enfoca en la inscripción pictórica de una pieza arqueológica hallada en Jaltipan, Veracruz, México. La pieza, asociada con la cultura olmeca prehispánica y elaborada en serpentinita, presenta un total de 62 signos. Aunque su interpretación es difícil, algunos de los signos son identificables a partir de la iconografía olmeca encontrada en otros sitios arqueológicos de Tabasco y Veracruz.

Copyright of Cirugía Plástica Ibero-Latinoamericana is the property of Cirugia Plastica Ibero-Latinoamericana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this work thin films of Ti6Al4V have been grown by rf magnetron sputtering, on steel 316L and they have been subjected to a later treatment of nitrurated by plasma, in function of the time, to settle down if changes exist in the mechanical properties for the incorporation from the nitrogen to the crystalline lattice of the film. The conditions used to grow these films were: Pressure 7x10-3 mbar, time of 1 hour and with a power 400 W. The films were nitrurated to a difference of potential of 500 V, to a pressure of 3 torr. The results of EDX reveal that the films this compound on the average of 78,3% Wt of Ti, 6.% Wt of Al, 12.0% Wt of V and 2.1 Wt % N. On the other hand, the results of DRX show that the film grows along the plane (110) of the β phase (Ti stabilized with V) of the alloy. Finally, the mechanical tests carried out on the films nitrurated indicate that the microhardness increases lightly. [ABSTRACT FROM AUTHOR]

Copyright of Colombia Medica is the property of Universidad del Valle and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The magnetic, hyperfine and structural properties of an iron ore sample from Uvo - Paz del Río-Boyacá (5.98º N, 72.72º W) are studied. The ore was characterized both in its natural state as well as after mechanical milling for different milling times. Mössbauer Spectroscopy, vibrating sample magnetometry and X-ray diffraction (XRD) were employed for characte-rization. This work illustrates the complexity of the iron ores and the effect of milling upon the magnetic, structural and hyperfine properties. [ABSTRACT FROM AUTHOR]

We report the production of type perovskite ceramics Sr2FeMnO6, Ba2NdSbO6, Sr2YSbO6 y Ho- Ba2Cu3O7 by means the standard solid state reaction recipe. X-ray diffraction analysis shows that these materials crystallize in complex perovskite with the A2BB'O6 form. [ABSTRACT FROM AUTHOR]

This research paper shows the electrical characterization of tablets type complex perovskite (Sr2FeMnO6, Ba2NdSbO6 and Sr2YSbO6 -semiconductors to room temperature) and HoBa2Cu3O7 (conductor to room temperature but superconductor to 92 K) by means of the Impedance Spectroscopy (IS) technique in solid materials. The measures were carried out in a rank of frequency of 1 mHz to 100 KHz, the experimental assembling was shown, the analysis of the impedance change based on the frequency was also shown, the elements of constant phase that appear in the transmission lines were presented, and the equivalent circuits that can be used to simulate the behavior of the electrical conductivity of these perovskites were also shown. [ABSTRACT FROM AUTHOR]

This work presents the use of the technique of current pulsant inverse, pulse direct current and direct current for electrodeposition thin films Cu/Cd in double-layer shape on Zamak substrate. The influence of the different variables was studied involved in each one of the processes: voltage and time of deposition (VHigh and tHigh), voltage and time of breakup (VLow and tLow) and the load cycle (θ=tHigh/tHigh+tLow), obtaining as answer the monitory of the average anodic (ILow) and cathodic (IHigh) in function of the time anodic (tLow) and cathodic (tHigh), respectively. The electrodeposits of Cu/Cd was characterized by means ray x diffraction being observed the structure and composition in each one of the films obtained. It was observed that the control pulsant of the voltage during the deposit to influence in the composition of the electrodeposits. [ABSTRACT FROM AUTHOR]

By means of the Van der Pauw method we found the sign and the Hall carrier density of a set of Gal-xInxAsySbl-y films. The samples were grown by Liquid Phase Epitaxy technique over single crystal GaSb;Te (100) substrates. All samples presented in this work were found to be n-type, and the calculated volume densities show strongly doped films. The characteristic I-V curves have a non linear behavior, for both Ag and Au electric contacts. The line shape is typical of Schottky barrier, been Ag a better option for the Schottky device. [ABSTRACT FROM AUTHOR]

This work presents the equivalent electric circuit RC used for the characterization from the behavior to the corrosion of Ti6Al4V thin films in atmospheres simulating biological fluids. The films were deposited on 316L steel substrates by rf magnetron sputtering. The electrochemical technique employed to evaluate the behavior of corrosion was the Electrochemical Impedance Spectroscopy (EIS), by which Bode diagrams were carried out, permitting to obtaining the parameters of corrosion: resistance of the electrolytic solution, polarization resistance and impedance of transfer of electric load in function of the frequency. [ABSTRACT FROM AUTHOR]

The obtaining of movies thick anódicas of aluminum oxide on aluminum 2024-T3, it was made using the direct current technique, using as electrolyte a sulfuric acid solution, H2SO4 15% v/v, at 20°C during 30 minutes, to three different current desnsidades (10, 15 and 20 mA/cm2). they were carried out microdureza tests Vikers, coefficient of friction rehearsals and ruggedness measures. The results show the influence that has the current density applied in the formation of the oxide movies. Indicating that the current density influences with an increase of movie thickness and an increase in the securities of microdureza of the system, obtaining thick movies, standardize and adherent [ABSTRACT FROM AUTHOR]

The purpose of this article is show from physical point of view, the theoretical review of the electrochemical processes that happen in an interphase metal-dissolution, starting off of termodinamicos and electrostatic concepts that entail to the deduction of the kinetic model that describes or governs the anodic and cathodic processes implicitly revelated in the present loading density in the system. this model it is known him like Butler-Volmer's kinetics equation of, which by means of first approach reveals the linear behavior between the load and the energy of the carrier as it happens in the Ohm's law, being the fundamental base for the development of conventional electrochemical techniques such as linear polarization resistance (LPR), Tafel polarization curves, galvanostatic pulse (GALVAPULSE) and Electrochemical Frequency Modulation (EFM) among others, used for measurements of parameters that allow to determine of corrosion rate in conductive materials. [ABSTRACT FROM AUTHOR]

Gal-xInxAsySbl-y epitaxial films grown by Liquid Phase Epitaxy were etched by using an acid solution during different dipping times. The etching rate was obtained by means of thickness measurements for different wetting times. The optical response and its variation with etching were measured by photoluminescence technique. The differences in the energy position of optical response for the different etching times were associated to the removal of the most superficial oxide layers. We found a good material to cover the substrate surface to obtain the etching rate. [ABSTRACT FROM AUTHOR]

The technical Electrochemical Frequency Modulation (EFM) is presented, as a new method for the evaluation of the corro-sion rate and electrochemical analysis of materials. The technique consists in the generation of two potentials of sinusoidal type of frequencies 2Hz and 5Hz with amplitude of 10mV added and applied simultaneously to the sample evaluated front of the corrosion, measuring to the exit the answer in current of the harmonic and intermodulation frequencies of the applied signs. To validate this technique they were carried out tests of curved of polarization Tafel, on test tubes of concrete Port-land with several carbonatación levels and these results were confronted with those obtained in the technique (EFM). [ABSTRACT FROM AUTHOR]

The production 0films anodic is presented in a solution of sulfuric acid 15% v/v and to a temperature of 20 °C, with constant agitation (100 rpm), and to three different current densities (10, 15 and 20 mA/cm2), to substitute the chromic acid in the process of anodizing of the aluminum alloy 2024-T3. The electrochemical impedance spectroscopy (EIS) and the polarization curves Tafel was the techniques employees to observe the process of corrosion. The appropriate equivalent circuits are detected by means of EIS with base in these circuits they are the parameters corresponding of the porous layer and the layer barrier. Additionally it is found that the anticorrosive estates of the movies anódicas formed in sulfuric acid vary with the density of current employee. [ABSTRACT FROM AUTHOR]