208 research outputs found
Complicaciones en las fracturas supracondíleas de húmero en la infancia.
La fracturas supracondíleas de húmero tienen gran incidencia en la infancia, y además pueden
presentar una gran cantidad de complicaciones previas y posteriores al tratamiento. Se realiza una revisión de las
complicaciones más frecuentes en las fracturas supracondíleas de húmero en los niños.Supracondylar fractures of the humerus present high incidence in children, moreover, a high per
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centage of complications may be present, both previously as posteriorly to treatment. A review of the most com
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mon complications in supracondylar humerus fractures in children is performed
Revisión y actualización del tratamiento de las fracturas supracondíleas de húmero en la infancia
La fractura supracondílea de húmero en la infancia es una patología con gran incidencia en los niños.
Su tratamiento está rodeado de muchos puntos controvertidos. Se realiza una revisión histórica del tratamiento de esta
patología y una actualización de las nuevas técnicas que han surgido a lo largo de los años.Supracondylar fracture of the humerus in childhood presents high incidence in children. The treat
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ment of this fracture is surrounded by many controversial points. A historical review of the treatment of this injury
and an update about emerging techniques during last years were done
Low and high Reynolds number flows inside Taylor cones
Liquid motions inside Taylor cones exhibit interesting features which are not well understood yet. In addition to the flow rate injected through the electrified needle to which the conical meniscus is anchored, the action of the tangential electrical stress on the cone surface induces a recirculating meridional motion, towards the apex along the generatrix and away from it along the axis. Sometimes, a vigorous swirl is observed. The characteristic value of the liquid velocity is found to be highly dependent on both the electrical conductivity and the viscosity of the liquid, so that the Reynolds number of the liquid flow varies from very small values (creeping flow) for the case of highly conducting and viscous liquids to relatively large values for liquids with sufficiently low values of the liquid conductivity and viscosity. Theoretical conical flows for low and high values of the Reynolds number show qualitatively good agreement with photographs of real flows inside Taylor cones. In particular, the existence of a vigorous swirl which is observed in the electrospraying of paraffins and other poorly conducting and low viscosity liquids can be explained as bifurcation of a primarily nonswirling meridional flow when the Reynolds number reaches a critical value.Comisión Interministerial de Ciencia y Tecnología PB96-0679-C02-0
ZnO-mesoporous glass scaffolds loaded with osteostatin and mesenchymal cells improve bone healing in a rabbit bone defect
The use of 3D scaffolds based on mesoporous bioactive glasses (MBG) enhanced with therapeutic ions, biomolecules and cells is emerging as a strategy to improve bone healing. In this paper, the osteogenic capability of ZnO-enriched MBG scaffolds loaded or not with osteostatin (OST) and human mesenchymal stem cells (MSC) was evaluated after implantation in New Zealand rabbits. Cylindrical meso-macroporous scaffolds with composition (mol %) 82.2SiO2–10.3CaO–3.3P2O5–4.2ZnO (4ZN) were obtained by rapid prototyping and then, coated with gelatin for easy handling and potentiating the release of inorganic ions and OST. Bone defects (7.5 mm diameter, 12 mm depth) were drilled in the distal femoral epiphysis and filled with 4ZN, 4ZN + MSC, 4ZN + OST or 4ZN + MSC + OST materials to evaluate and compare their osteogenic features. Rabbits were sacrificed at 3 months extracting the distal third of bone specimens for necropsy, histological, and microtomography (µCT) evaluations. Systems investigated exhibited bone regeneration capability. Thus, trabecular bone volume density (BV/TV) values obtained from µCT showed that the good bone healing capability of 4ZN was significantly improved by the scaffolds coated with OST and MSC. Our findings in vivo suggest the interest of these MBG complete systems to improve bone repair in the clinical practice
Cognitive boundary signals in the human medial temporal lobe shape episodic memory representation
While experience unfolds continuously, memories are organized as a set of discrete events that bind together the “where”, “when”, and “what” of episodic memory. This segmentation of continuous experience is thought to be facilitated by the detection of salient environmental or cognitive events. However, the underlying neural mechanisms and how such segmentation shapes episodic memory representations remain unclear. We recorded from single neurons in the human medial temporal lobe while subjects watched videos with different types of embedded boundaries and were subsequently evaluated for memories of the video contents. Here we show neurons that signal the presence of cognitive boundaries between subevents from the same episode and neurons that detect the abstract separation between different episodes. The firing rate and spike timing of these boundary-responsive neurons were predictive of later memory retrieval accuracy. At the population level, abrupt neural state changes following boundaries predicted enhanced memory strength but impaired order memory, capturing the behavioral tradeoff subjects exhibited when recalling episodic content versus temporal order. Successful retrieval was associated with reinstatement of the neural state present following boundaries, indicating that boundaries structure memory search. These findings reveal a neuronal substrate for detecting cognitive boundaries and show that cognitive boundary signals facilitate the mnemonic organization of continuous experience as a set of discrete episodic events
ZnO-mesoporous glass scaffolds loaded with osteostatin and mesenchymal cells improve bone healing in a rabbit bone defect.
The use of 3D scaffolds based on mesoporous bioactive glasses (MBG) enhanced with therapeutic ions, biomolecules and cells is emerging as a strategy to improve bone healing. In this paper, the osteogenic capability of ZnO-enriched MBG scaffolds loaded or not with osteostatin (OST) and human mesenchymal stem cells (MSC) was evaluated after implantation in New Zealand rabbits. Cylindrical meso-macroporous scaffolds with composition (mol %) 82.2SiO2–10.3CaO–3.3P2O5–4.2ZnO (4ZN) were obtained by rapid prototyping and then, coated with gelatin for easy handling and potentiating the release of inorganic ions and OST. Bone defects (7.5 mm diameter, 12 mm depth) were drilled in the distal femoral epiphysis and filled with 4ZN, 4ZN+MSC, 4ZN+OST or 4ZN+MSC+OST materials to evaluate and compare their osteogenic features. Rabbits were sacrificed at 3 months extracting the distal third of bone specimens for necropsy, histological and microtomography (µCT) evaluations. Systems investigated exhibited bone regeneration capability. Thus, trabecular bone volume density (BV/TV) values obtained from µCT showed that the good bone healing capability of 4ZN was significantly improved by the scaffolds coated with OST and MSC. Our findings in vivo suggest the interest of these MBG complete systems to improve bone repair in the clinical practice
Automatic translation of the dactilologic language of hearing impaired by adaptive systems
Una de las principales limitaciones que presentan las personas con discapacidad auditiva está directamente
relacionada con su dificultad para interactuar con otras personas, ya sea de forma verbal o a través de sistemas auxiliares basados en
la voz y el audio. En este artículo se presenta el desarrollo de un sistema integrado de hardware y software, para el reconocimiento
automático del lenguaje dactilológico de señas utilizado por personas con este tipo de discapacidad. El hardware está compuesto
por un sistema inalámbrico adherido a un guante, el cual posee un conjunto de sensores que capturan una serie de señales generadas
por los movimientos gestuales de la mano, y un modelo por adaptación basado en los principios de la computación neuronal, el cual
permite su reconocimiento en términos de un lenguaje dactilológico en particular. Los resultados arrojados por el sistema integrado
mostraron gran efectividad en el reconocimiento de las vocales que conforman el lenguaje dactilológico en español, esto gracias a la
capacidad que posee el modelo de asociar un conjunto de señales de entrada, con un movimiento dactilológico en particular.One of the main limitations of the people with hearing impairment is directly related to their difficulty interacting
with others, either verbally or through auxiliary systems based on voice and audio. This paper presents the development of an
integrated system of hardware and software for automatic fingerspelling sign language used by people with this type of disability. The
hardware system comprises a glove which has a set of wireless sensors that capture a series of signals generated by the hand gestures,
and a adaptive model based on the principles of neural computation, that allows recognition of a particular dactilologic language.
Results from the integrated system showed great effectiveness in recognizing vowels from the dactilologic Spanish language. This
recognition was influenced by the dimensionality reduction made by the neural model of the input signals representing movements,
and the sensitivity factor that sets the limit between recognition and learning
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