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This article presents a low cost prototype potentiostat, which allows to control electrical variables in obtaining coatings by electrodeposition. The QFD (Quality Function Deployment) methodology was used as a planning tool in order to determine the characteristics that should have the potentiostat along the entire process of obtaining the prototype. The development of the research was based on the design and implementation of a prototype potentiostat that can handle three basic functions of electrodeposition. One first function, chronoamperometry lets to keep a constant voltage in the range of 0 V to 20 V and measures the current delivered to the system. A second function, chronopotentiometry maintains constant a current in a range of 0 A to 2 A and measures the voltage (potential). A third function, cyclic voltammetry, works in the same ranges of chronoamperometry (0 V to 20 V) and excites the system by signals as triangular wave, saw tooth, sine, and square, among others. These implemented features were compared to one conventional potentiostat, demonstrating its efficiency in controlling electrochemical processes.

Introduction The most frequent cardiac primary tumors are Mixomas, typically being located in the left atrium. They are usually incidental findings, but probable symptoms include constitutional syndrome, syncope, congestive symptoms, or embolism. The diagnosis is based upon clinical imaging tests (with the TEE being the test of choice) which define the characteristics of the chosen treatment, surgery. Clinical case A 79-year-old female with a medical history of HTA and Diabetes with retinopathy nephropathy. She was hospitalized 2 months earlier with a constitutional syndrome being diagnosed of a Giant cell arteritis. Then she came to the emergency room presenting with oliguria, edema and dyspnea with a 10 kg weight loss. The tests performed showed low voltajes in the EKG, anemization and the TTE showed a mass inside the right atrium. Then she was hospitalized and a CT scan confirmed the presence of an aparent Mixoma. The patient was treated with surgery and the diagnosis was confirmed by pathology. Discussion We are describing the case of a pluripathological patient with congestive symptoms due to cardiac insuffciency, so the differential diagnosis must include thromboembolisms, valvulopathies and pulmonary hypertension. The constitutional syndrome can be explained due to the relation of the Mixoma with IL-6 and the anemization could be caused by the hemolyisis of the tumor. After two years of the surgery no further symptoms appeared, and no evidence of the mass where it had been seen in the imaging tests.

Introduction Atrial septal defects are the second most frequent congenital heart diseases and their treatment of choice is the percutaneous approach. Complications associated are infrequent and are mainly related with the puncture. Other complications such as embolism or endocarditis are uncommon. Clinical case A 17-year-old woman whose only medical history of interest was an ostium secundum-type atrial septal defect that was treated percutaneously implanting a 24-mm Amplatzer septal occlude. 15 months after the procedure she came to the emergency room presenting 40°C fever and a headache. Physical examination and tests results were normal, being discharged with antibiotic treatment. She returned 24 hours later due to persistence of the same symptoms. An echocardiogram was performed, revealing an endocarditic growth and uncomplete endothelization of the amplatzer. Following 10 days of antibiogram-guided therapy with good response, she underwent surgery. The device was extracted and the defect closed. PCR was positive for H. Parainfluenzae. The patient was discharged on the 7th day with antibiotic therapy. Discussion This case is relevant due to the late presentation of IE, incomplete endothelization and to being caused by infrequent IE germ source with a negative blood culture. Despite the low prevalence of these complications, it is necessary to rule them out through imaging tests as well as microbiological tests. Appropriate length of bacterial coverage usually extends from 6 months to 1 year after implantation. Documented cases of prosthetic IE related to incorrect endothelial coverage can lead to reassessing the time period during which prophylaxis should be maintained.

Despite the evolution of surgical techniques, pain continues to be one of the most frequent disorders in the postoperative period of cardiac surgery (CS), leading to the appearance of complications in the acute period and impairment of quality of life due to the appearance of chronic pain. In this narrative review, we aim to analyze the prognostic factors for the appearance of postoperative pain after CS, to locate and quantify the severity of neuropathic pain, and determine the most appropriate assessment methods in these patients.Postoperative pain in CS is a complex pain, which associates neuropathic, somatic and visceral components. Its origin is multifactorial; factors depending on the patient, the preoperative symptoms and the type of intervention, as well as sequelae derived from the surgery itself, determine the variability in its manifestation. Multiple studies have tried to identify the risk factors for its development, but the quantification of pain is limited by the subjective perception of the patients.Neurologists can play a relevant role in the differentiation of the different types of pain after CS, thanks to the understanding of its neurobiological bases, properly handling neuromodulators that control the neuropathic component of pain and collaborating in the indication of invasive techniques, necessary occasionally in the management of these patients.Dolor en el postoperatorio de cirugía cardíaca: bases neurobiológicas y tratamiento.Introducción. A pesar de la evolución de las técnicas quirúrgicas, el dolor sigue siendo uno de los trastornos más frecuentes en el postoperatorio de la cirugía cardíaca (CCA), lo que condiciona la aparición de complicaciones en la fase aguda y el deterioro de la calidad de vida por la aparición de dolor crónico. En esta revisión narrativa pretendemos analizar los factores pronósticos de la aparición de dolor postoperatorio tras CCA, localizar y cuantificar la gravedad del dolor neuropático y determinar cuáles son los métodos de evaluación más adecuados en estos pacientes. Desarrollo. El dolor postoperatorio en la CCA es un dolor complejo, que asocia componentes neuropáticos, somáticos y viscerales. Su origen es multifactorial; factores dependientes del paciente, de la clínica preoperatoria y el tipo de intervención, así como de secuelas derivadas de la propia cirugía, determinan la variabilidad en su manifestación. Múltiples estudios han intentado identificar los factores de riesgo de su desarrollo, pero la cuantificación del dolor se ve limitada por la percepción subjetiva del paciente. Conclusiones. Los neurólogos pueden tener un papel relevante en la diferenciación de los distintos tipos de dolor tras CCA, gracias a la comprensión de sus bases neurobiológicas, manejando adecuadamente neuromoduladores que controlen el componente neuropático del dolor y colaborando en la indicación de técnicas invasivas, necesarias ocasionalmente en el manejo de estos pacientes.

Biogenic hydroxyapatite (BHAp) is a widely used material in the biomedical area due to its similarities with the bone tissue mineral phase. Several works have been spotlighted on the thermal behavior of bone. However, little research has focused on determining the influence of calcination temperature in the physicochemical and bioactive properties of BHAp. In this work, a study of the physicochemical properties’ changes and bioactive response of BHAp produced from porcine femur bones using calcination temperatures between 900 to 1200 °C was conducted. The samples’ structural, morphological, and compositional changes were determined using XRD, SEM, and FTIR techniques. XRD results identified three temperature ranges, in which there are structural changes in BHAp samples and the presence of additional phases. Moreover, FTIR results corroborated that B-type substitution is promoted by increasing the heat treatment temperature. Likewise, samples were immersed in a simulated biological fluid (SBF), following the methodology described by Kokubo and using ISO 23317:2014 standard, for 3 and 7 days. FTIR and SEM results determined that the highest reaction velocity was reached for samples above 1000 °C, due to intensity increasing of phosphate and carbonate bands and bone-like apatite morphologies, compared to other temperatures evaluated.

User Experience (UX) Design of Artificial Intelligence (AI) applications that assist knowledge-intensive tasks are usually the result of an iterative and fuzzy process. Although the combination of state-of-the-art technology with human expertise is undoubtedly valuable in the industry context, designing a user-centered tool that fits in the everyday activities of knowledge workers – supporting and augmenting their potential – is not a trivial work. User research uncovers pain points and opportunities, bringing the insights that inspire designers and Human Computer Interaction (HCI) experts. It allows a clear understanding of the context, which is the essence of a consistent interaction experience. Nevertheless, revealing the UX of the application and how AI in this context reshapes knowledge workers' everyday tasks is not straightforward and might also be an iterative process. In this paper, we present findings from a case study of the use of a storytelling method to design and validate the UX of AI assistants for the Oil & Gas industry by using an animated sketch-based video.

The aim of this study was to evaluate the effects of electrochemical treatments in the germination of cassava stakes, variety MCol 2066 (Chiroza), under the effect of different AC voltages and exposure times.The electrochemical treatment was held out in an electrochemical cell made of ice with two stainless steel electrodes located on two parallel sides of the cellular telephone. KNO3at 0.05M dissolved in water was used as electrolytic solution.The results show that the electrochemical treatments affected the germination time of the stakes favorably. The best voltages for the application of the treatments were 6, 9, 13 and 20 V AC, with an exposure time of 5 min. Treatment with 6 V AC showed better global results with respect to the variable responses.

Resumen Introduccion La reparacion endovascular del aneurisma de aorta abdominal (EVAR) ha supuesto desde su llegada y desarrollo una disminucion en la mortalidad precoz con respecto a la cirugia convencional. Como factores predictivos de mortalidad se han identificado el deterioro de funcion renal preoperatorio, la enfermedad pulmonar obstructiva cronica y la cardiopatia isquemica. Objetivo Evaluar la influencia en la supervivencia a largo plazo de los factores de riesgo preoperatorios y del deterioro de funcion renal perioperatorio en los pacientes sometidos a EVAR en nuestro centro. Material y metodos Se realizo un estudio observacional retrospectivo en pacientes sometidos a EVAR en nuestro centro entre los anos 2008 y 2012. Se hizo un analisis de la supervivencia a medio y largo plazo, llevado a cabo mediante curvas de Kaplan-Meier. Se estudio la influencia de los factores de riesgo preoperatorios y del deterioro de funcion renal perioperatorio sobre la supervivencia empleando el modelo de regresion de Cox. Resultados Se incluyeron 79 pacientes con una edad media de 75,2 anos (57,6-85,9). La mediana del tiempo de seguimiento fue de 38 meses (0,4-83,4). Durante este periodo de tiempo se registraron 26 muertes (32,9%). La probabilidad de supervivencia al cabo de un ano fue del 93,7%; a los 2 anos del 82,3%; a los 4 anos del 68,9%; y a los 6 anos del 56,5%. Una mayor tasa de supervivencia se asocio con cifras analiticas de creatinina menores de 1,2 mg/dl a las 24 h y a los 7 dias, y filtrado glomerular mayor de 60 ml/min a las 24 h y a los 7 dias. El analisis multivariante evidencio una probabilidad de muerte 2,39 veces mayor en los pacientes que presentaron un valor analitico de creatinina a las 24 h mayor de 1,2 mg/dl con respecto a los que mostraron una cifra menor de 1,2 mg/dl (HR: 2,39; IC95%: 1,06-5,42); p = 0,037). Conclusion El deterioro de funcion renal tras la EVAR es un factor independiente de mal pronostico a largo plazo. Tanto en la preparacion preoperatoria como durante el postoperatorio deben ponerse los medios necesarios encaminados a corregir las circunstancias que provoquen un deterioro de la funcion renal.

La síntesis y estudio de biomateriales con propiedades biomecánicas y de biocompatibilidad es un tema de continua investigación por parte de la comunidad científica. Compuestos como la hidroxiapatita (HA) y la brushita, que poseen interesantes propiedades y a la vez son biocompatibles, están siendo utilizados como capa barrera entre materiales como el acero 316L y medios biológicos, disminuyendo así el flujo de iones de hierro del acero hacia los fl uidos biológicos. Si bien estudios recientes presentan avances en términos de la adherencia de estos materiales a diferentes metales, aún hay desafíos abiertos en pro de mejorar su adherencia sobre el metal deseado. En este trabajo se obtuvieron recubrimientos compuestos de bicapas de brushita y dióxido de titanio (TiO2). A continuación, se presentan los protocolos seguidos para síntesis de los recubrimientos de brushita, dióxido de titanio y sus bicapas sobre acero 316 L, así como la caracterización estructural mediante espectrometría infraroja (FTIR), difracción de rayos X (XRD), microscopia electrónica de barrido (SEM) y espectroscopia de energía dispersiva (EDS) de los recubrimientos obtenidos. Los resultados muestran que la combinación brushita/ TiO2 parece tener una buena efectividad, dado que el dióxido de titanio ayuda a la adherencia de la brushita.