854 research outputs found

    Matrix construction as dermal substitutes: potential application in skin regeneration

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    La pérdida de grandes porciones de piel limita su capacidad de regeneración, haciendo difícil su tratamiento. Mediante la ingeniería de tejidos se han desarrollado sustitutos dérmicos que promueven la regeneración; sin embargo, es necesario hallar un material para el crecimiento de fibroblastos que sea un sustituto dérmico adecuado. En este trabajo se construyeron matrices tridimensionales porosas de colágeno y colágeno-ácido hialurónico evaluando su potencial como sustituto dérmico. Las matrices se entrecruzaron con 1-etil-3-(3-dimetilaminopropil) carbodiimida hidrocloruro. Se evaluó la porosidad, se realizaron pruebas de degradación, evaluación de adherencia celular con fibroblastos humanos y, ensayos de viabilidad y proliferación. Las matrices presentaron poros de 50 μm de diámetro uniformemente distribuidos. Las matrices de colágeno y colágeno-ácido hialurónico (2:8 y 4:6) presentaron una degradación progresiva con pesos similares. Luego de 24 horas en cultivo, los resultados de la prueba de MTT mostraron que los fibroblastos en colágeno proliferaron; mientras que los fibroblastos en colágeno-ácido hialurónico no evidenciaron proliferación. Aunque la estructura porosa y la tasa de degradación de las matrices son similares, las de colágeno brindan mejores condiciones de adhesión y proliferación a los fibroblastos cultivados en comparación con las que tienen ácido hialurónico como adición, convirtiéndose en el mejor andamio para ser empleado como sustituto dérmico entre las matrices evaluadas.Wounds can cause loss of skin that limits the skin regeneration, making the treatment more difficult to address. The tissue engineering has developed skin substitutes that promote skin regeneration; however, it is imperative to find materials that allow fibroblast growth in order to find an appropriate skin substitute. The construction of tridimensional porous collagen and collagenhyaluronic acid matrixes crosslinked with 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide hydrochloride is presented in order to evaluate their potential use in skin regeneration therapies. Matrix porosity was evaluated. Degradation tests, human fibroblast adherence, viability and proliferation tests were performed. Matrixes had a uniform distributed porosity with mean diameters of 50 μm. Both collagen and collagen-hyaluronic acid (2:8 and 4:6) matrixes presented a progressive degradation rate with similar weight. After 24 hours under culture, the number of fibroblasts seeded on collagen matrixes were doubled, while the number of fibroblast seeded on collagen-hyaluronic acid matrixes remained similar. Even though porous structure and degradation rate of different types of constructed matrixes in this study are similar, collagen matrixes offer better adhesion and proliferation conditions for seeded fibroblasts in comparison with hyaluronic acid added matrixes, making them the best scaffold to be employed as a dermic substitute among the matrixes compared here

    P67 195. Cirugía del tromboembolismo pulmonar masivo en el enfermo crítico

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    La extracción de los trombos pulmonares en el tromboembolismo pulmonar masivo antes de 1953 (operación de Trendelenburg) cosechó fracaso tras fracaso. Desde el advenimiento de la circulación extracorpórea (CEC) el porcentaje de éxito de esta operación mejoró notablemente, no habiendo dejado de aumentar hasta la actualidad, existiendo series que reflejan porcentajes de hasta el 94% de supervivencia inmediata, con 86 y 83% de supervivencia actuarial a 1 y 3años.Presentamos un caso de paciente varón de 35años sin enfermedad previa ni antecedentes familiares de enfermedad tromboembólica. Consulta por insuficiencia respiratoria, siendo diagnosticado por tomografía computarizada de tromboembolismo en AP izquierda, la cual ocluye. El ECO-Doppler de MMII descarta trombosis venosa profunda (TVP). Una nueva tomografía computarizada informa de persistencia de la obstrucción de AP izquierda y sus ramas, que parece haber aumentado. En ecocardiografía transtorácica (ETT) dilatación de cavidades derechas con función de ventrículo derecho (VD) normal y presión sistólica de la arteria pulmonar (PSAP) de 70 mmHg. Los estudios para investigar trombofilia fueron negativos.Tras unos días empeora su situación, produciéndose dos paradas cardiorrespiratorias, de las que es reanimado y tratado inmediatamente con TNK. La tomografía computarizada muestra la existencia de nuevo episodio de tromboembolismo pulmonar que afecta a la AP derecha gravemente.Es intervenido quirúrgicamente bajo CEC sin parada circulatoria, extrayéndose molde trombótico de tronco y ambas ramas de la AP. La evolución postoperatoria fue favorable. En tomografía computarizada de control se observan limpios el tronco y las ramas de la AP, con cierto compromiso en ramas subsegmentarias de la AP izquierda.Se muestran imágenes de la intervención y tomografía computarizada pre y posquirúrgicas

    Total Absorption Spectroscopy Study of 92^{92}Rb Decay: A Major Contributor to Reactor Antineutrino Spectrum Shape

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    The antineutrino spectra measured in recent experiments at reactors are inconsistent with calculations based on the conversion of integral beta spectra recorded at the ILL reactor. 92^{92}Rb makes the dominant contribution to the reactor spectrum in the 5-8 MeV range but its decay properties are in question. We have studied 92^{92}Rb decay with total absorption spectroscopy. Previously unobserved beta feeding was seen in the 4.5-5.5 region and the GS to GS feeding was found to be 87.5(25)%. The impact on the reactor antineutrino spectra calculated with the summation method is shown and discussed.Comment: 6 pages, 3 figure

    Transcription, indexing and automatic analysis of judicial declarations from phonetic representations and techniques of forensic linguistics

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    Recientes avances tecnológicos han permitido mejorar los procesos judiciales para la búsqueda de información en los expedientes judiciales asociados a un caso. Sin embargo, cuando técnicos y peritos deben revisar pruebas almacenadas en vídeos y fragmentos de audio, se ven obligados a realizar una búsqueda manual en el documento multimedia para localizar la parte que desean revisar, lo cual es una tarea tediosa y que consume bastante tiempo. Para poder facilitar el desempeño de los técnicos, el presente proyecto consiste en un sistema que permite la transcripción e indexación automática de contenido multimedia basado en tecnologías de deep-learning en entornos de ruido y con múltiples interlocutores, así como la posibilidad de realizar análisis de lingüística forense sobre los datos para ayudar a los peritos a analizar los testimonios de modo que se aporten evidencias sobre la veracidad del mismo.Recent technological advances have made it possible to improve the search for information in the judicial files of the Ministry of Justice associated with a trial. However, when judicial experts examine evidence in multimedia files, such as videos or audio fragments, they must manually search the document to locate the fragment at issue, which is a tedious and time-consuming task. In order to ease this task, we propose a system that allows automatic transcription and indexing of multimedia content based on deep-learning technologies in noise environments and with multiple speakers, as well as the possibility of applying forensic linguistics techniques to enable the analysis of witness statements so that evidence on its veracity is provided.Este proyecto ha sido financiado por el Instituto de Fomento de la Región de Murcia con fondos FEDER dentro del proyecto con referencia 2018.08.ID+I.0025

    Nutritional status and high adherence to the mediterranean diet in colombian school children and teenagers during the COVID-19 pandemic according to sex

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    La actual pandemia de COVID-19 ha generado una serie de cambios en las rutinas diarias de las personas, incluidos niños y adolescentes, de una forma sin precedentes, lo que constituye un desafío mundial en salud pública. El aislamiento social ha sido una medida profiláctica para evitar la propagación del virus; sin embargo, ha generado impactos negativos en la salud física y emocional de padres, cuidadores, niños y adolescentes alrededor del mundo. El objetivo del presente estudio fue evaluar los efectos del confinamiento provocado por la pandemia del COVID-19 a nivel del estado nutricional, patrones dietéticos y de comportamiento de niños y adolescentes de educación básica primaria de una pequeña localidad de Colombia. Se evaluaron parámetros antropométricos como IMC Z-score, perímetro de cintura y relación cintura/talla en 266 escolares y adolescentes. Se aplicó un cuestionario con características sociodemográficas, clínicas y de estilo de vida y el KIDMED para conocer aspectos nutricionales. Un total de 102 estudiantes (38⋅3 %) fueron clasificados con estado nutricional alterado, siendo 39 (14⋅7 %) clasificados con sobrepeso y 36 (13⋅5 %) con obesidad. La prevalencia de alta adherencia a la dieta mediterránea fue del 12 %, IC 95 % (0⋅08, 0⋅16). El sobrepeso fue más frecuente en mujeres (26/39, 66⋅7 %; P = 0⋅0439), y la obesidad fue discretamente más frecuente en hombres (19/36, 52⋅7 %; P = 0⋅7193). Observamos una situación nutricional, dietética y comportamental preocupante en los niños y adolescentes estudiados durante el confinamiento asociado a la pandemia de COVID-19. Esto devela la necesidad de establecer estrategias y/o políticas públicas en nuestra localidad que ayuden a promover un adecuado desarrollo biopsicosocial del paciente pediátrico y su grupo familiar.The current COVID-19 pandemic has generated a series of changes in the daily routines of people, including children and teenagers, in an unprecedented way, which constitutes a global challenge in public health. Social isolation has been a prophylactic measure to prevent the spread of the virus; however, it has generated negative impacts on the physical and emotional health of parents, caregivers, children and teenagers around the world. The objective of the present study was to evaluate the effects of confinement caused by the COVID-19 pandemic at the level of nutritional status, dietary and behavioural patterns of elementary school children and teenagers in a small town of Colombia. Anthropometric parameters such as BMI Z-score, waist circumference and waist/height ratio were evaluated in 266 school children and teenagers. A questionnaire with socio-demographic, clinical and lifestyle characteristics and the KIDMED were applied to learn about nutritional aspects. A total of 102 students (38⋅3 %) were classified as having altered nutritional status, being 39 (14⋅7 %) classified as overweight and 36 (13⋅5 %) with obesity. The prevalence of high adherence to the Mediterranean diet was 12 %, 95 % CI (0⋅08, 0⋅16). Overweight was more prevalent in women (26/39, 66⋅7 %; P = 0⋅0439), and obesity was discreetly more frequent in men (19/36, 52⋅7 %; P = 0⋅7193). We observed a worrying nutritional, dietary and behavioural situation in the children and teenagers studied during the confinement associated with the COVID-19 pandemic. This unveils the need to establish strategies and/or public policies in our town that help to promote an adequate biopsychosocial development of the paediatric patient and their family grou

    Purcell Enhancement and Wavelength Shift of Emitted Light by CsPbI3 Perovskite Nanocrystals Coupled to Hyperbolic Metamaterials

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    Manipulation of the exciton emission rate in nanocrystals of lead halide perovskites (LHPs) was demonstrated by means of coupling of excitons with a hyperbolic metamaterial (HMM) consisting of alternating thin metal (Ag) and dielectric (LiF) layers. Such a coupling is found to induce an increase of the exciton radiative recombination rate by more than a factor of three due to the Purcell effect when the distance between the quantum emitter and HMM is nominally as small as 10 nm, which coincides well with the results of our theoretical analysis. Besides, an effect of the coupling-induced long wavelength shift of the exciton emission spectrum is detected and modeled. These results can be of interest for quantum information applications of single emitters on the basis of perovskite nanocrystals with high photon emission rates

    Charge separation relative to the reaction plane in Pb-Pb collisions at sNN=2.76\sqrt{s_{\rm NN}}= 2.76 TeV

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    Measurements of charge dependent azimuthal correlations with the ALICE detector at the LHC are reported for Pb-Pb collisions at sNN=2.76\sqrt{s_{\rm NN}} = 2.76 TeV. Two- and three-particle charge-dependent azimuthal correlations in the pseudo-rapidity range η<0.8|\eta| < 0.8 are presented as a function of the collision centrality, particle separation in pseudo-rapidity, and transverse momentum. A clear signal compatible with a charge-dependent separation relative to the reaction plane is observed, which shows little or no collision energy dependence when compared to measurements at RHIC energies. This provides a new insight for understanding the nature of the charge dependent azimuthal correlations observed at RHIC and LHC energies.Comment: 12 pages, 3 captioned figures, authors from page 2 to 6, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/286

    A note on comonotonicity and positivity of the control components of decoupled quadratic FBSDE

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    In this small note we are concerned with the solution of Forward-Backward Stochastic Differential Equations (FBSDE) with drivers that grow quadratically in the control component (quadratic growth FBSDE or qgFBSDE). The main theorem is a comparison result that allows comparing componentwise the signs of the control processes of two different qgFBSDE. As a byproduct one obtains conditions that allow establishing the positivity of the control process.Comment: accepted for publicatio

    Transverse sphericity of primary charged particles in minimum bias proton-proton collisions at s=0.9\sqrt{s}=0.9, 2.76 and 7 TeV

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    Measurements of the sphericity of primary charged particles in minimum bias proton--proton collisions at s=0.9\sqrt{s}=0.9, 2.76 and 7 TeV with the ALICE detector at the LHC are presented. The observable is linearized to be collinear safe and is measured in the plane perpendicular to the beam direction using primary charged tracks with pT0.5p_{\rm T}\geq0.5 GeV/c in η0.8|\eta|\leq0.8. The mean sphericity as a function of the charged particle multiplicity at mid-rapidity (NchN_{\rm ch}) is reported for events with different pTp_{\rm T} scales ("soft" and "hard") defined by the transverse momentum of the leading particle. In addition, the mean charged particle transverse momentum versus multiplicity is presented for the different event classes, and the sphericity distributions in bins of multiplicity are presented. The data are compared with calculations of standard Monte Carlo event generators. The transverse sphericity is found to grow with multiplicity at all collision energies, with a steeper rise at low NchN_{\rm ch}, whereas the event generators show the opposite tendency. The combined study of the sphericity and the mean pTp_{\rm T} with multiplicity indicates that most of the tested event generators produce events with higher multiplicity by generating more back-to-back jets resulting in decreased sphericity (and isotropy). The PYTHIA6 generator with tune PERUGIA-2011 exhibits a noticeable improvement in describing the data, compared to the other tested generators.Comment: 21 pages, 9 captioned figures, 3 tables, authors from page 16, published version, figures from http://aliceinfo.cern.ch/ArtSubmission/node/308
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