123 research outputs found

    Organización de un programa de implantes cocleares

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    A cochlear implant (CI) programme brings together a number of professionals who, during the stages of selection, surgery, programming, rehabilitation and monitoring, develop a series of tasks aimed at promoting comprehensive attention to the implanted patient. The aim of this paper was to describe in detail the tasks in each of the phases described in a programme of CI, materials and necessary equipment and the role of the professionals involved. It also raised a number of recommendations on how to develop a CI programme gradually to facilitate the progression from the simplest to the mos

    Tipos de implantes activos de oído medio

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    Active middle ear implants are classified as piezoelectric implants, which use the properties of piezoelectric materials. There are two types of piezoelectric implants: monomorphic and dimorphic; electromagnetic transduction uses a magnet, usually a rare earth magnet (e.g. samarium cobalt) and an energizing coil. This magnetic field causes the magnet to vibrate, which in turn, through the tympanic-ossicular chain, causes movement of the cochlear fluids. Electromechanical transduction is a variation of electromagnetic transduction

    Influence of Baseline Fluctuation Cancellation on Automatic Measurement of Motor Unit Action Potential Duration

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    The aim of this work is to analyze the influence of a method for baseline fluctuation (BLF) cancellation for electromyographic (EMG) signals on automatic methods for measurement of the motor unit action potential (MUAP) duration. These methods include four conventional automatic methods (CAMs) and a recently published wavelet transform method (WTM). A set of 182 MUAPs from 170 EMG recordings were studied. The CAMs and the WTM were applied to the MUAPs before and after applying BLF cancellation to the recordings. A gold standard of duration marker positions (GSP) ws manually established. The accuracy of each algorithm was estimated as the dfference between its positions and the GSP. Accuracies were compared for the 5 methods and for each method before and after BLF cancellation. A significant difference between accuracy pre- and post-BLF removal was found in two CAMs; markers were closer to the GSP after BLF removal. For all MUAPs, the differences between WTM markers and the GSP were the smallest, and significant differences were not found for the WTM before and after BLF cancellation. The management of BLF is an important issue in EMG signal processing and BLF removal must be considered in extraction and analyse of MUAP waveforms. The BLF removal method improved the performance of two CAMs for MUAP duration measurement. The WTM was the most accurate and was not affected by BLF.

    Anatomical basis of sleep

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    El sueño es un estado biológico activo, periódico, en el que se distinguen las etapas NREM y REM, que se alternan sucesivamente durante la noche. Intervienen los relojes biológicos en la modulación del sistema, así como neurotransmisores específicos. Se trata de una red neuronal compleja, en la que intervienen diversas zonas del sistema nervioso central. Los procesos oníricos están controlados además de forma neural. Se resume la historia de las investigaciones sobre el tema, desde el siglo XIX hasta nuestra época. Hay que destacar los recientes descubrimientos de Lugaresi y su equipo, que, al describir el insomnio familiar grave, dieron importancia al núcleo dorsomedial del tálamo en la instauración de la fase de sueño profundo. Al grupo de Reinoso se debe el hallazgo de que el “director de orquesta” en la instauración del sueño REM es la zona ventral paramediana del núcleo reticular pontino ora

    Epifisiólisis femoral proxima: revisión de 44 casos

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    Se revisan 44 niños con 47 epifisiólisis femorales proximales. Veintitrés desplazamientos fueron leves, 18 moderados y 6 severos. Todas las epifisiólisis excepto 1 se trataron quirúrgicamente. En 10 casos se fijó profilácticamente la cadera contralateral. Existió penetración articular por el implante en 17 (30%) de las 56 caderas fijadas. El seguimiento medio ha sido de 56 meses (rango: 3 a 148 meses). Los resultados, según criterios clínicos y radiográficos, han sido excelentes o buenos en el 91% de los deslizamientos leves, el 77% de los moderados y el 33% de los severos. Las complicaciones fueron 2 casos de condrólisis, ambos asociados a penetración articular. En 2 (6%) de los pacientes donde no se realización profiláctica se produjo deslizamiento contralateral. En nuestro estudio los resultados se correlacionan con la cuantía del deslizamiento. No recomendamos la fijación profiláctica contraletal.We review 44 children with 47 slipped capital femoral epiphysis. There were 23 mild slips, 18 moderate, and 6 severe. Operative treatment was performed in all but one of the slips. In 10 cases prophylactic pinning of the contralateral hip was performed. Penetration of the joint by the implant was present in 17 (30%) of the 56 fixed hips. The average follow-up was 56 months (range: 3 to 178 months). The results, according to clinical and rocntgenographic parameters were excellent or good in 91% of mild slips, 77% of moderate and 33% of severe. As complications there were two cases of chondrolysis, both associated with joint penetration. In 2 (6%) patients where prophylactic pinning was not performed, contralateral hip slipping developed. In our study, results correlate with slip severity. We do not recommend prophylactic contralateral pinning

    Hearing Impairment and Quality of Life in Adults with Asymmetric Hearing Loss: Benefits of Bimodal Stimulation

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    Objectives: Bimodal stimulation for asymmetric hearing loss is an emerging treatment with proven audiometric outcomes. Our objectives are to assess the changes of the hearing impairment and the quality of life of patients treated with this type of stimulation, when compared to a unilateral Cochlear Implant (CI) stimulated condition. Materials and methods: 31 patients with asymmetric hearing loss (Group 1) were recruited for the study. They were divided into three groups, based on their hearing loss in the ear treated with the hearing aid: Group 1A (Pure Tone Audiometry (PTA) between 41 and 70 decibels (dB)); Group 1B, (PTA between 71 and 80 dB) and Group 1C (PTA between 81 and 90 dB). 30 patients had profound, bilateral hearing loss. Then, users of a unilateral cochlear implant were recruited for the control group. Their hearing impairment and quality of life were analyzed with questionnaires Abbreviated Profile of Hearing Aid Benefit (APHAB), Speech, Spatial and Qualities of Hearing Scale (SSQ) and the Health Utilities Index (HUI). They were followed up for at least 2 years. Results: The group with the asymmetric hearing loss obtains a statistically significant clinical improvement in the APHAB under category "with hearing aid" compared to "without hearing aid". The group with the asymmetric hearing loss benefits more across basically all variables compared with the control group in the SSQ. Group 1A obtains the best outcome of the sample in the HUI. Conclusion: Bimodal stimulation and better hearing in the ear treated with the hearing aid reduce hearing impairment and improve the quality of life

    Papatrónica – dispositivo de código abierto para la medición de golpes y prevención de daños mecánicos

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    En Argentina, según datos de la Secretaría de Agroindustria, se pierden y desperdician anualmente 14,5 millones de toneladas de alimentos en las etapas de producción, almacenamiento, transporte y procesamiento, siendo la cadena frutihortícola la que presenta mayor proporción de pérdidas. Los daños mecánicos generados por golpes ocasionan una parte importante de estas pérdidas, directamente como consecuencia de la ruptura de células y tejidos, e indirectamente por generar lesiones que permiten el ingreso de patógenos que producen necrosis o pudriciones. El objetivo de este trabajo fue prototipar una plataforma abierta y modular de código abierto y bajo costo que permita determinar los puntos donde se producen golpes que puedan afectar los tubérculos de papa, pero también fácilmente adaptable a otros cultivos o productos, o a la medición de otras variables.Sociedad Argentina de Informática e Investigación Operativ

    Fluorochemicals from fluorspar via a phosphate-enabled mechanochemical process that bypasses HF

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    All fluorochemicals-including elemental fluorine and nucleophilic, electrophilic, and radical fluorinating reagents-are prepared from hydrogen fluoride (HF). This highly toxic and corrosive gas is produced by the reaction of acid-grade fluorspar (>97% CaF2) with sulfuric acid under harsh conditions. The use of fluorspar to produce fluorochemicals via a process that bypasses HF is highly desirable but remains an unsolved problem because of the prohibitive insolubility of CaF2. Inspired by calcium phosphate biomineralization, we herein disclose a protocol of treating acid-grade fluorspar with dipotassium hydrogen phosphate (K2HPO4) under mechanochemical conditions. The process affords a solid composed of crystalline K3(HPO4)F and K2-xCay(PO3F)a(PO4)b, which is found suitable for forging sulfur-fluorine and carbon-fluorine bonds
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