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The present work consists of proposing a new design of balloon-expandable aortic valve stent for use in patients with aortic valve stenosis. Finite element simulations were carried out to determine the Von Mises stresses and deformations and thereby select the design parameters of this device, which will allow its manufacturing and proper operation. The symmetrical condition of the stent facilitated the modeling process, as well as the determination of the smallest reduced diameter of the stent, a necessary condition for it to be moved safely within the artery. In this analysis, 316L stainless steel was used, an elastoplastic, isotropic and homogeneous behavior of the material was considered, also varying the thickness and radius of curvature at the ends of the stent sections. Loads were applied at the joints of these sections, obtaining equivalent stresses below the resistance limit of the material and above the elastic limit. The greatest reduction in stent diameter was obtained with a wire thickness of 0.5 mm and a radius of curvature of 0.5 mm. The mean diameter of the open device (22.987 mm) was reduced to 7.65 mm when applying a pressure of 43.8 MPa. [ABSTRACT FROM AUTHOR]

The electrical network is one of the least detected sources of electromagnetic interference, but it causes adverse effects on the medical equipment that is in its radius of action. The objective of this work is to analyze the effect of the magnetic field on the signal emitted by the Audix V equipment. A magnetic field generator, a gaussmeter, a signal simulator and an Audix equipment were transmitted. The research was carried out, following a methodology developed from different methods found in the literature. Screenshots of the signals emitted by the Audix V with visible influence on the parameters that characterize it were obtained by applying field values even below the 3.77 µT allowed by the IEC. It was concluded that there may be an error in the diagnosis due to the deformation caused by the electromagnetic field on the characteristics of the signal. [ABSTRACT FROM AUTHOR]

The interference in the neonatal intensive care area is mainly due to the crowding of medical equipment that the patient must count on to save his life. The objective of this work is to analyze the behavior of the magnetic field generated by medical equipment, according to its placement and quantity, in a neonatal care area. To carry it out, a gaussmeter was used, following a measurement methodology used by this team in previous research. It was obtained as a result that the electromagnetic environment of the area complies with the recommendations of the International Commissions on non-ionizing Radiation Protection (ICNIRP), but not with the limits established by the International Electrotechnical Commission (IEC) for electromagnetic compatibility. Recommendations were issued to reduce these values, concluding that the separation between equipment is the most recommended and effective method. [ABSTRACT FROM AUTHOR]

The work reveals the study of the electromagnetic environment in several computer laboratories belonging to the Universidad Tecnológica de La Habana "José Antonio Echeverría" (CUJAE). The main objective is to analyze the behavior of the existing magnetic field in these laboratories, taking into account the different situations that may arise. For the measurement of the magnetic field, the gaussimeter model PCE-G28 was used and for the characterization of the magnetic field of the laboratories a measurement protocol was developed, based on the analysis of international standards. The results obtained between 0,01 µT and 9,31 µT reflect the areas of greatest intensity, generally coinciding where the electrical protection panel is located and where the power supply enters the laboratories. Although the measurements do not exceed the limits recommended by International Commissions on non-ionizing Radiation Protection (ICNIRP) in 2010, some prevention measures were recommended as a result of the characteristics observed during the days of measurement. [ABSTRACT FROM AUTHOR]

Nowadays, the problems associated with the use of the non-ionizing radiations, among them the sources they generate magnetic fields of low frequency (50-60 Hz), have retrieved a growing interest between the scientific community. The agglutination of medical equipment according the constructive disposition of the area in which find, lead to invisible interference that could affect the functioning itself. For this reason, this working group decided to perform measurements of low-frequency magnetic field. It was used the instrument of measurement EMDEX II and it was take into account different situation in a neonatal neurophysiology test consultation. It was concluded that there are external interferences that reach the medical equipment is located. The values of magnetic field issue and its origin were obtained. It recommends to move the medical equipment to another space where exist less intensity of magnetic field. [ABSTRACT FROM AUTHOR]

In the present work, three types of tubular scaffolds were obtained from pig skin collagen and chicken feet, which was isolated using a 0,5 molar acetic acid solution. The procedure used for the formation of the pores was lyophilization, which was carried out at a freezing temperature of -40 °C. Tubular structure was achieved with steel molds, by modifying the mold dimensions to achieve wall thicknesses of 0,1; 0,5 and 1mm. Collagen was characterized by acrylamide gel electrophoresis tests and Fourier transform infrared spectrometry (FTIR). It was confirmed the presence of type I collagen in all cases. The collagen production process yielded 4,35 % starting with pig skin and 4.5% from chicken feet. The characterization of the scaffolds was carried out by determining the parameters of swelling, water absorption, biodegradability, as well as a morphological analysis by optical microscopy and finally the determination of the maximum resistance using a tensile test. As a result, chicken feet scaffolds had higher water absorption, lower biodegradability, lower swelling rate and lower strength than pig skin scaffold. [ABSTRACT FROM AUTHOR]