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Introduction: Liver transplantation is the only curative treatment for patients with end-stage liver disease. Neurological complications are one of the main causes of morbidity and mortality. Objective: To study neurological complications after liver transplantation in paediatric patients. Methods: We conducted a retrospective study, including all paediatric patients younger than 17 years undergoing liver transplantation over a 12-year period at our centre. Results: Forty-six liver transplantations were performed in 38 patients. The most common indication was biliary atresia. Up to one-third of patients presented neurological complications, with psychomotor agitation being the most frequent. Incidence of neurological complications was significantly higher in the group of infants than in older age groups. Encephalopathy was more common in patients with acute liver failure than in those with chronic liver failure. Conclusions: Neurological complications, and particularly psychomotor agitation, are common after liver transplantation in paediatric patients. Resumen: Introducción: El trasplante hepático (TH) es el único tratamiento curativo para enfermos en situación de fallo hepático terminal. Las complicaciones eurológicas (CN) son una causa importante de morbimortalidad. Objetivos: Estudiar la incidencia de CN en pacientes pediátricos sometidos a un TH. Pacientes y métodos: Estudio retrospectivo en el que se incluyeron todos los pacientes menores de 17 años sometidos a TH durante un periodo de 12 años. Resultados: Se realizaron 46 TH en 38 pacientes. La indicación más frecuente fue la atresia de vías biliares. En un tercio de los pacientes hubo alguna CN, siendo la más frecuente la agitación psicomotora. Se encontró una menor incidencia de CN en el grupo de lactantes con respecto a los pacientes de mayor edad, de forma estadísticamente significativa. El desarrollo de encefalopatía en casos de fallo hepático agudo fue más frecuente que en aquellos con insuficiencia hepática crónica. Conclusiones: Las CN en los niños son frecuentes después de un TH, siendo la más frecuente la agitación psicomotora.

The aim of this paper is to relate innovation with the broadcasters' business model, by way of a bibliometric and review analysis. This comprises to study how they have incorporated the innovation and the effect of a disruptive innovation (as the Internet and other technologies) in their business model. To achieve these objectives a review of the scientific literature has been carried out, followed of an analysis in which obtained papers were classified according three dimensions: (i) Value Architecture Innovation, (ii) Value Offering Innovation and (iii) the Revenue Model Innovation. These dimensions are based on a reinterpretation of a previous classification which consider that business model innovation materialises with a change of the company that affects at least one out of the three mentioned dimensions. In this way, a classification of the reviewed documents has been established based on these dimensions, showing that broadcasters have adopted a sustained business model innovation, with 48%, 44% and only 8%, respectively, in each dimension. By means of a scientific mapping of the keywords of the documents reviewed, a series of main and secondary topics have been established within each dimension, which have been analysed in terms of their contents and temporal evolution. It discusses the difficulties faced by broadcasters in adapting to the new audiovisual ecosystem. This study also argues that the Internet is one of the most disruptive innovations they have had to face and, therefore, in order to survive, they must take on this type of innovation to transform their business model.

Abstract The objective was to build a prosthesis with its elements such as socket, forearm and hand. The prostheses that are below the elbow generated the motivation for the investigation, being an important factor the correct adaptation of the socket to the stump in a personalized way creating an adjustment due to the vacuum that is generated between these elements, without the need to use a harness. For the design and construction of the prosthesis prototype, a Kinect device was used to obtain a point cloud of the geometric model, the alginate for the manufacture of the mold and plaster that is used to obtain the shape of the hand. The result is an individualized prosthesis design built based on the patient's own dimensions and validated using finite elements; with the purpose of making changes and improvements in the design, to have a prosthesis of easy placement and use.

We analyze the scenario of modulating the potential strength of bound atoms in an optical honeycomb lattice patterned by an electric field to emulate uniaxial strain. This modulation can be achieved by a combination of the strength of the patterned electric field and gauge vector effects using the Floquet approach. We show that such a modulation allows one to follow through a topological transition between a semi-metal and a band insulator, when two non-equivalent K points merge as a function of the electric field strength. We explicitly compute the wavefunctions for the moving K points and the Chern numbers up to the transition. Anisotropic effective masses and the insulating gap are described close to the semimetal-insulator transition.

A chemical characterization of turning color table olives of the Sigoise variety was made through their processing as natural-style. Polyphenols, sugars, tocopherols, fatty acids, and antioxidant activity in the olives were monitored throughout the elaboration process. Oleuropein, salidroside, hydroxytyrosol 4-glucoside, rutin, ligustroside and verbascoside showed a decrease of 16.90-83.34%, while hydroxytyrosol increased during the first months of brining. Glucose was consumed by 90% due to the metabolism of the fermentative microbiota. The tocopherol content remained stable during the process and only the α-tocopherol decreased. The fatty acids were not affected. The loss in antioxidant compounds resulted in a decrease in the percentage of DPPH radical inhibition from 75.91% in the raw fruit to 44.20% after 150 days of brining. Therefore, the turning color natural table olives of the Sigoise variety are a good source of bioactive compounds.

The consumption of fermented vegetables is widespread throughout the world and represents an important component of the human diet with considerable contribution to the food supply for a world popula­tion in continuous growth. Many of the fermented vegetables share a general process which requires salting and acidification steps. Among the microorganisms responsible for fermentation, lactic acid bacteria are the most relevant with important organoleptic, quality and safety benefits. This review deals with the microbial ecology of fermented vegetables focusing on the biodiversity of lactic acid bacteria, the most important molecular tech­niques used for their identification and genotyping, their importance for the formation of biofilms as well as their use as starter cultures for obtaining high-quality and safe vegetable products.

Element uptake from substrate and resorption capacity of nutrients before leaf shedding are frequently species-specific and difficult to determine in natural settings. We sampled populations of Rhizophora mangle (salt-excluding species) and Laguncularia racemosa (salt-secreting species) in a coastal lagoon in the upper section of the Maracaibo strait in western Venezuela to estimate accumulation and resorption of mineral elements. Leaves collected fortnightly during 4~months within the rainy season were stratified as young, adult, old, and senescent. We measured changes in concentration of essential elements (N, P, S, K, Mg, Ca, Mn, Fe) and Na (elemental analyzer and plasma spectrometer), leaf succulence (water/area), and specific leaf area (area/mass) and calculated relative resorption or accumulation of elements in senescent leaves before abscission. Succulence was similar in young leaves of both species and increased with age, more abruptly in L. racemosa. Concentrations of N, K, and Mg were higher in R. mangle, whereas those of P, Na, Ca, and S were higher in L. racemosa. Concentration of K per unit leaf water decreased with age in both species; however, Na concentration in R. mangle remained at a similar level until increasing markedly in senescent leaves, whereas in L. racemosa it increased throughout the leaf lifespan. Relative changes based on leaf mass, leaf area, or whole leaf did not differ statistically. On a leaf mass basis both species showed resorption of C, N, P, and K and accumulation of S, Na, Mg, Ca, Mn, and Fe. However, R. mangle was more efficient restricting Na and S uptake, resorbing P, and accumulating Fe than L. racemosa. The P / N resorption ratio is > 1 in R. mangle and < 1 in L. racemosa. We conclude that those differences are related to higher root permeability to Na and S salts in the salt-secreting species and to higher P requirements of R. mangle compared to L. racemosa. Our results give a comprehensive picture of nutrient dynamics in the foliage of mangrove species with contrasting mechanisms of salt regulation.

Se ha evaluado el comportamiento mecánico y estructural de dos aceros inoxidables corrugados, el austenítico EN 1.4301 (AISI 304) y el dúplex EN 1.4362 (AISI 2304), y se han comparado con el tradicional acero al carbono B500SD. El estudio se ha realizado en tres niveles: a nivel de barra, de sección y de pieza. Las diferentes características mecánicas de los aceros inoxidables condicionan el comportamiento a nivel de sección y de pieza estructural. El estudio del comportamiento frente a la corrosión de los dos aceros inoxidables se ha realizado mediante mediciones electroquímicas monitorizando el potencial de corrosión y la resistencia de polarización de armaduras embebidas en probetas de mortero contaminado con diferentes concentraciones de cloruros durante un tiempo de exposición de un año. Ambos aceros inoxidables permanecen en estado pasivo en las probetas para todos los contenidos de cloruros.

This paper discusses the stress-strain curves for a new low nickel stainless steel, a conventional AISI 304 stainless steel and a carbon steel commonly used in reinforced concrete structures. Ductility was studied in terms of ultimate tensile strength (fmax), elastic limit (fy) and total elongation at maximum force [ultimate strain; uniform elongation] (εmax). The three materials were assessed with internationally accepted criteria, such as plastic rotational capacity, necking region and the toughness index (total energy absorbed at uniform elongation). The findings were compared to the properties of three types of conventional reinforcing steel: 500SD, 500N and 500H (EC-2).

We discuss the Pauli Hamiltonian including the spin-orbit interaction within an U(1)×SU(2) gauge theory interpretation, where the gauge symmetry appears to be broken. This interpretation offers new insight into the problem of spin currents in the condensed matter environment, and can be extended to Rashba and Dresselhaus spin-orbit interactions. We present a few outcomes of the present formulation: i) it automatically leads to zero spin conductivity, in contrast to predictions of Gauge symmetric treatments, ii) a topological quantization condition leading to voltage quantization follows, and iii) spin interferometers can be conceived in which, starting from an arbitrary incoming unpolarized spinor, it is always possible to construct a perfect spin filtering condition.

Objetivo: valorar la mejoría endoscópica tras el tratamiento con argón plasma utilizado para el control sintomático de las rectitis actínicas crónicas. Diseño y pacientes: estudio prospectivo de 48 meses de duración, con 38 pacientes (26 hombres y 12 mujeres, con edad media de 70,9 ± 7,38 años). Todos presentaban algún grado de rectorragia y/o anemia. Se realizaron entrevistas clínicas, analíticas y sesiones endoscópicas con argón, de forma periódica mensual, hasta la normalización analítica y cese del sangrado, con un seguimiento posterior de 24 meses. Para valorar la mejoría se utilizaron parámetros analíticos, gradación de sangrado (Chutckan) y un índice endoscópico. Resultados: el tiempo medio trascurrido entre el inicio y la finalización del seguimiento fue de 28,5 ± 3,9 meses. La media de sesiones administradas por paciente ha sido de 3,6 ± 2,7. Si comparamos los síntomas antes, después del tratamiento existe una disminución significativa en el grado de rectorragia según la clasificación de Chutkan (2,29 ± 1,08 vs. 0,59 ± 1,12, p < 0,05). Cuando comparamos los valores medios de la hemoglobina, antes y después del tratamiento apreciamos una aumento estadísticamente significativo (11,33 ± 3,05 mg/dl vs. 14,014 ± 1,29 mg/dl, p < 0,001) así como los valores medios de ferritina (31,15 ± 66, 45 µg/dl vs. 80,60 ± 55,60 µg/dl, p < 0,05). En el índice endoscópico, también existe una mejoría evidente de la afectación endoscópica tras el tratamiento con respecto a la friabilidad (p < 0,0001) y porcentaje de mucosa afecta (p < 0,0001). Conclusión: el argón plasma es eficaz y la realización del índice endoscópico es una herramienta útil para valorar la mejoría endoscópica de las lesiones tras el tratamiento.Objectives: to evaluate endoscopic improvement after argon plasma coagulation (APC) in symptomatic patients with chronic radiation proctopathy. Methods and patients: a prospective study of 38 patients with radiation proctitis (26 males and 12 females, mean age 70.9 ± 7.38 yrs), and with rectal bleeding and or anemia. We performed monthly interviews, blood tests, and APC sessions until rectal bleeding had ceased and hemoglobin and ferritin levels were improved, with a follow-up of 24 months. We used blood testing, bleeding scores (Chutckhan's index), and endoscopic scores to evaluate improvement. Results: mean time between inclusion and follow-up completion was 28.5 ± 3.9 months. Mean number of sessions per patient was 3.6 ± 2.7. There was a significant decrease (2.29 ± 1.8 vs. 0.59 ± 1.12, p < 0.05) in rectal bleeding (Chutckan score) from baseline after APC. There was a significant increase in hemoglobin levels (11.3 ± 3.05 vs. 14.014 ± 1.29, p < 0.001) and ferritin levels (31.15 ± 66.45 vs. 80.60 ± 55.6, p < 0.05) from baseline after APC. Also, there was improvement in the endoscopic index at the end of treatment, as well as in friability (p < 0.0001) and involved surface area (p < 0.0001). Conclusion: argon plasma coagulation is an effective technique, and the endoscopic index is a useful tool to evaluate endoscopic improvement.

Objetivo: Identificar, mediante análisis de regresión múltiple, las variables de influencia en el tiempo de acceso a atención especializada (listas de espera), y analizar las zonas de salud con tiempo de acceso elevado, en función de las mencionadas variables. Diseño: Estudio descriptivo transversal, retrospectivo, del tiempo de acceso a atención especializada, durante los años 1997 y 1998. Emplazamiento: Área 20 de la Conselleria de Sanitat de la Comunidad Valenciana; 12 zonas de salud; 204.424 habitantes. Intervenciones: Se recogen variables de demanda (tipo de municipio, envejecimiento e índices de dependencia poblacional, porcentaje de pensionistas), de oferta (edad, sexo, formación y situación laboral del médico, tamaño del cupo) y de consumo (porcentaje de derivación a especializada por mil habitantes, tiempo medio de acceso a especializada (en días naturales) por zona y año, frecuentación y presión asistencial. Se construye un modelo de regresión múltiple por eliminación (hacia atrás), tomando como variable dependiente el tiempo medio de espera (TE) y como independiente el resto. La ecuación resultante permitió calcular el TE esperado por zona de salud y la desviación de su TE real sobre el esperado. Se consideró zona con TE elevado cuando su desviación superaba la media más una desviación estándar de dicha distribución. Resultados: El tiempo de espera medio para acceder a especializada fue de 37 días en 1997 y 34 días en 1998. Existe una correlación significativa (p < 0,005) entre el TE y el porcentaje de población menor de 14 años (r = -0,693), el porcentaje de población entre 14 y 65 años (r = 0,517), la frecuentación (r = 0,689) y la población de costa (r = 0,470). Nuestro modelo final incluyó: el porcentaje de población menor de 14 años, la frecuentación y la población de costa (F = 41,803; p < 0,000; r = 0,945; r² = 0,893). Se identificaron tres zonas (37,5%) con TE elevado. Conclusiones: La frecuentación, el porcentaje de población pediátrica y la proximidad a la costa guardan una estrecha correlación con el tiempo de acceso a atención especializada, lo cual condiciona las listas de espera.Objective: To identify the variables influencing waiting time for specialized care (waiting lists) through multiple regression analysis and to analyze the health districts with long waiting times according to these variables. Design: Descriptive, cross sectional and retrospective study of waiting times for access to specialized care between 1997 and 1998. Setting: Area 20 of the Health Department of the Autonomous Community of Valencia (Spain) consisting of 12 health districts with 204,424 inhabitants. Interventions: The following variables were gathered: variables influencing demand: type of municipality, aging and indexes of dependent population, and percentage of pensioners; variables influencing supply: age, sex, training and professional stability of the doctor, and size of the patient list; variables influencing resource consumption: percentage of referrals to specialized care per thousand inhabitants, mean WT for access to specialized care (in natural days) by district and year, number of consultations, and workload. A multiple regression model was constructed through (backward) elimination, taking the mean WT as the dependent variable and the remaining variables as independent variables. The resulting equation enabled calculation of the «expected» WT per health district and the deviation of the real WT from the expected WT. A district was considered to have a high WT when its deviation was above the mean plus one standard deviation of the distribution. Results: The mean WT for access to specialized care was 37 days in 1997 and 34 days in 1998. A significant correlation (p < 0.005) was found between WT and the percentage of the population aged less than 14 years (r = -0.693), the percentage of the population aged between 14-65 years (r = 0.517), the number of consultations (r = 0.689), and coastal population (r = 0.470). Our final model included: percentage of the population aged less than 14 years, number of consultations, and coastal population (F = 41.803; p < 0.000; r = 0.945; r² = 0.893). Three districts (37.5%) with high WTs were identified. Conclusions: The number of consultations, the percentage of the pediatric population, and proximity to the coast were closely correlated with WT for specialized care, with a consequent influence on waiting lists.

Objetivo: La desinfección del agua con cloro en las plantas de potabilización da lugar a la formación de trihalometanos (THM). Estos compuestos están asociados a efectos adversos para la salud. En este estudio se determinó la concentración de THM en el agua para consumo humano suministrada por las redes de distribución de los dos principales sistemas de potabilización de agua del Estado Carabobo, la planta Alejo Zuloaga y el embalse Pao-Cachinche que forman el Sistema Regional del Centro I (SRC-I) y la planta Lucio Baldo Soules y el embalse Pao-La Balsa que forman el Sistema Regional del Centro II (SRC-II). Métodos: Se analizaron un total de 144 muestras recolectadas durante 6 muestreos que se realizaron durante los años 2000 y 2001. La concentración de THM se determinó por cromatografía de gases, mediante la técnica de headspace. Se determinaron las concentraciones para los siguientes THM: cloroformo (CHCl3), bromoformo (CHBr3), dibromoclorometano (CHBr2Cl) y diclorobromometano (CHCl2Br). Resultados: La concentración de THM totales estuvo entre 47,84 y 93,23 μg/l. El CHCl3 fue el compuesto predominante, representando el 83% de total de THM para el SRC-I y el 82% en el SRC-II. Se encontró que las concentraciones de THM totales en el SRC-I (Red Baja y Red San Diego) son significativamente superiores (p < 0,05) con respecto a la concentración máxima permisible establecida por la Agencia de Protección Ambiental de los EE.UU. (80 μg/l) para el total de los cuatro THM. Conclusiones: Los resultados demuestran que en la zona de estudio existe un riesgo de efectos adversos para la salud por la presencia de THM en agua de consumo humano, especialmente en la Red Baja y Red San Diego del SRC-I.Objective: Disinfection of water with chlorine in water treatment plants leads to the formation of trihalomethanes (THMs). These compounds are associated with adverse health effects. The aim of this study was to analyze THM concentrations in the water provided for human consumption in the two main water treatment systems of Carabobo State: the Alejo Zuloaga plant and the Pao-Cachinche reservoir, which form the Central Regional System I (CRS I), and the Lucio Baldo Soules plant and the Pao-La Balsa reservoir, which form the Central Regional System II (CRS II). Methods: We analyzed 144 water samples collected in 6 samplings carried out in 2000 and 2001. THM concentrations were determined by gas chromatography using the headspace technique. The concentrations of the following THMs were measured: chloroform (CHCl3), bromoform (CHBr3), chlorodibromomethane (CHBr2Cl) and bromodichloromethane (CHCl2Br). Results: The concentration of total THMs was between 47.84 µg/l and 94.23 µg/l. CHCl3 was the most commonly formed compound representing 83% of all THMs in the CRS I and 82% in the CRS II. The concentrations of total THMs in the CRS I, specifically in the Baja and San Diego networks, were significantly higher (p < 0.05) than permissible levels set by the American Environmental Protection Agency (80 µg/l) for the sum of all four THMs. Conclusions: The results show that in the area studied there is a risk of adverse health effects due to THMs in drinking water, especially in the Baja and San Diego networks.

Graphene consists in a single-layer carbon crystal where 2p_z electrons display a linear dispersion relation in the vicinity of the Fermi level, conveniently described by a massless Dirac equation in 2+1 spacetime. Spin-orbit effects open a gap in the band structure and offer perspectives for the manipulation of the conducting electrons spin. Ways to manipulate spin-orbit couplings in graphene have been generally assessed by proximity effects to metals that do not compromise the mobility of the unperturbed system and are likely to induce strain in the graphene layer. In this work we explore the U(1)×SU(2) gauge fields that result from the uniform stretching of a graphene sheet under a perpendicular electric field. Considering such deformations is particularly relevant due to the counter-intuitive enhancement of the Rashba coupling between 30-50% for small bond deformations well known from tight-binding and DFT calculations. We report the accesible changes that can be operated in the band structure in the vicinity of the K points as a function of the deformation strength and direction.

We address the description of a graphene Corbino disk in the context of a tight binding approach that includes both kinetic and Rashba spin-orbit coupling due to an external out-of-plane electric field. Persistent equilibrium currents are induced by an external magnetic field breaking time reversal symmetry. By direct diagonalization, we compute the spectrum and focus on the dispersion near the K points at the Fermi level. The dispersion keenly reproduces that of a continuum model in spite of the complexity of the boundary conditions. We validate the assumptions of the continuum model in terms of predominant zig-zag boundaries conditions and weak sub-band coupling. The wave functions displaying the lowest transverse modes are obtained, showing the predominance of edge states with charge density at the zig-zag edges. The persistent charge currents, nevertheless, do not follow the traditional argument of current cancellation from levels below the Fermi level, and thus they depart in the tight-binding from those found in the continuum model.

Abstract Mangrove communities were selected in the state of Santa Catarina, Brazil, near their southernmost limit of distribution, to study mineral nutrient relation in soils and plants. Communities included three true mangrove species, Rhizophora mangle, Laguncularia racemosa and Avicennia germinans, and two associated species, the fern Acrostichum danaeifolium, and the grass Spartina densiflora. The sites included communities in the lower Río Tavares near Florianopolis city, Sonho beach near Palhoça city, and the Santo Antonio lagoon. These sites included a full range of mangroves under humid climate where winter temperatures, instead of salinity, may be the main factor regulating their productive capacity and species composition. Soil salinity was determined by the concentration of soluble Na, and soil C and N were linearly correlated indicating their association in organic matter. Tavares site showed higher specific conductivity, and concentrations of Na and Mg in the soil layer below 40 cm depth, indicating larger influence of marine water. Isotopic signature of C increased with soil depth suggesting that microorganisms decomposing organic matter are releasing 13C depleted CO2. Nitrogen isotopic signature decreased with soil depth, indicating enrichment in 15N possibly as a result of denitrification in the upper soil layers. Mineral elements in leaf tissues showed A. schaueriana with higher concentrations of N, P, Na, K, Cu, Zn, and Na/Ca ratio. Spartina densiflora was characterized by the lowest N and K concentrations, and the highest concentrations of Al and Fe. Rhizophora mangle and L. racemosa had the highest Ca concentrations. Carbon isotopic signatures identified S. densiflora as a C4 plant, and A. schaueriana as the mangrove species occupying comparatively more water stressed microsites than the rest. Leaf nitrogen isotopic signatures were positive, in correspondence with the soil values. The results support the hypothesis that sites sampled were comparatively fertile, because sediment transport through fresh water run-off is predominant in humid coasts, and therefore plants were not limited by nutrient supply, nor particularly stressed by soil salinity.