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Los daños ocasionados por el exceso de la radiación de campos electromagnéticos se han convertido en un problema de salud mundial, siendo los niños unos de los mas propensos a contraer enfermedades por esta causa. En este trabajo se comprobó el ambiente electromagnético de cuatro cubículos de internamiento de la sala de terapia intensiva del hospital pediatrico ̈William Soler ̈. Se utilizó para este propósito un gaussímetro modelo Emdex II para realizar las mediciones, herramientas informáticas para procesar los datos obtenidos en ellas y las recomendaciones del 2010 emitidas por la Comision Internacional Para La Protección Contra Las Radiaciones No Ionizantes ( por sus siglas en inglés ICNIRP) como patrón para hacer comparaciones, las mediciones se realizaron según protocolos descritos en literaturas científicas y acorde con lo recomendado por la normas epidemiológicas del Ministerio de Salud Pública (MINSAP) cubano. Los valores medidos no sobrepasaron a los recomendados por la ICNIRP.

Abstract Background Cone-beam computed tomography (CBCT) acquisition during endovascular aneurysm repair is an emergent technology with more and more applications. It may provide 3-D information to achieve guidance of intervention. However, there is growing concern on the overall radiation doses delivered to patients, thus a low dose protocol is called when scanning. But CBCT images with a low dose protocol are degraded, resulting in streak artifacts and decreased contrast-to-noise ratio (CNR). In this paper, a Laplacian pyramid-based nonlinear diffusion is proposed to improve the quality of CBCT images. Method We first transform the CBCT image into its pyramid domain, then a modified nonlinear diffusion is performed in each level to remove noise across edges while keeping edges as far as possible. The improved diffusion coefficient is a function of the gradient magnitude image; the threshold in the modified diffusion function is estimated using the median absolute deviation (MAD) estimator; the time step is automatically determined by iterative image changes and the iteration is stopped according to mean absolute error between two adjacent diffusions. Finally, we reconstruct the Laplacian pyramid using the processed pyramid images in each level. Result Results from simulation show that the filtered image from the proposed method has the highest peak signal-noise ratio (81.92), the highest correlation coefficient (99.77%) and the lowest mean square error (27.61), compared with the other four methods. In addition, it has highest contrast-to-noise ratio and sharpness in ROIs. Results from real CBCT images show that the proposed method shows better smoothness in homogeneous regions meanwhile keeps bony structures clear. Conclusion Simulation and patient studies show that the proposed method has a good tradeoff between noise/artifacts suppression and edge preservation.

Abstract Background Bovine tuberculosis (bTB) poses serious risks to animal welfare and economy, as well as to public health as a zoonosis. Its etiological agent, Mycobacterium bovis, belongs to the Mycobacterium tuberculosis complex (MTBC), a group of genetically monomorphic organisms featured by a remarkably high overall nucleotide identity (99.9%). Indeed, this characteristic is of major concern for correct typing and determination of strain-specific traits based on sequence diversity. Due to its historical economic dependence on cattle production, Uruguay is deeply affected by the prevailing incidence of Mycobacterium bovis. With the world’s highest number of cattle per human, and its intensive cattle production, Uruguay represents a particularly suited setting to evaluate genomic variability among isolates, and the diversity traits associated to this pathogen. Results We compared 186 genomes from MTBC strains isolated worldwide, and found a highly structured population in M. bovis. The analysis of 23 new M. bovis genomes, belonging to strains isolated in Uruguay evidenced three groups present in the country. Despite presenting an expected highly conserved genomic structure and sequence, these strains segregate into a clustered manner within the worldwide phylogeny. Analysis of the non-pe/ppe differential areas against a reference genome defined four main sources of variability, namely: regions of difference (RD), variable genes, duplications and novel genes. RDs and variant analysis segregated the strains into clusters that are concordant with their spoligotype identities. Due to its high homoplasy rate, spoligotyping failed to reflect the true genomic diversity among worldwide representative strains, however, it remains a good indicator for closely related populations. Conclusions This study introduces a comprehensive population structure analysis of worldwide M. bovis isolates. The incorporation and analysis of 23 novel Uruguayan M. bovis genomes, sheds light onto the genomic diversity of this pathogen, evidencing the existence of greater genetic variability among strains than previously contemplated.

A stereolithography-based additive manufacturing technique has been used for the fabrication of advanced ceramics. A customised 3D printer using a Digital Light Processing (DLP) projector as UV source has been built to fabricate green bodies from photosensitive resins loaded with 25–60 wt% of alumina, 3- and 8-YSZ. The 3D-printed bodies were then sintered in the 1200–1500 °C and exhibited thermal stability. As expected, higher ceramic loadings rendered objects with higher density for a given sintering temperature. The limit of solid loading in the resin is approximately 60% and beyond those contents, the extra ceramic appears as powder loosely adhered to the sintered objects. Photogrammetry was used to evaluate the accuracy of the 3D printing process and highlighted a marked deviation between the CAD model and the resulting object, particularly in the top part of the specimens, possibly due to the use of volatile solvents which cause changes in the photoresins used. Nevertheless, that problem may be overcome by thermostatising the printer vat and/or using solvents with higher boiling point. The results obtained suggest the potential application of low cost DLP 3D printing techniques to process ceramics for a number of applications including ceramic fuel cells, piezoelectrics, dental applications, etc.

The electrode performance and degradation of 1:1 La2−xNiTiO6−δ:YSZ composites (x = 0, 0.2) has been investigated to evaluate their potential use as SOFC cathode materials by combining electrochemical impedance spectroscopy in symmetrical cell configuration under ambient air at 1173 K, XRD, electron microscopy and image processing studies. The polarisation resistance values increase notably, i.e., 0.035 and 0.058 Ωcm2 h−1 for x = 0 and 0.2 samples, respectively, after 300 h under these demanding conditions. Comparing the XRD patterns of the initial samples and after long-term exposure to high temperature, the perovskite structure is retained, although La2Zr2O7 and NiO appear as secondary phases accompanied by peak broadening, suggesting amorphization or reduction of the crystalline domains. SEM and TEM studies confirm the ex-solution of NiO with time in both phases and also prove these phases are prone to disorder. From these results, degradation in La2−xNiTiO6−δ:YSZ electrodes is due to the formation of La2Zr2O7 at the electrode–electrolyte interface and the ex-solution of NiO, which in turn results in the progressive structural amorphization of La18NiTiO6−δ phases. Both secondary phases constitute a non-conductive physical barrier that would hinder the ionic diffusion at the La2−xNiTiO6−δ:YSZ interface and oxygen access to surface active area.

Existen pocos estudios en Cuba sobre los mecanismos fundamentales de la interacción Universidad-Empresa y su repercusión en la actividad innovadora empresarial. Sin embargo, esta interacción ha asumido características interesantes sobre las que pueden extraerse enseñanzas que permiten lograr una mayor contribución al desarrollo socioeconómico del país. El trabajo tiene como objetivo analizar los mecanismos de interacción entre un centro de investigaciones de la CUJAE y las empresas cubanas del sector eléctrico. El estudio de caso se sustenta en una encuesta realizada a directivos y especialistas del sector eléctrico cubano y a profesores e investigadores de la universidad. En el trabajo se determinan los canales de interacción, según su importancia para la interacción entre ambos y se comparan con los resultados obtenidos en otros países latinoamericanos. Se encontró que mecanismos de mayor importancia para la interacción Universidad-Empresa en el caso analizado, resultaron similares a los encontrados en los otros países.

Thermal processes represent a considerable part of the total energy consumption in manufacturing industry, in sectors such as steel, aluminium, cement, ceramic and glass, among others. It can even be the predominant type of energy consumption in some sectors. High thermal energy processes are mostly associated to high thermal losses, (commonly denominated as waste heat), reinforcing the need for waste heat recovery (WHR) strategies. WHR has therefore been identified as a relevant solution to increase energy efficiency in industrial thermal applications, namely in energy intensive consumers. The ceramic sector is a clear example within the manufacturing industry mainly due to the fuel consumption required for the following processes: firing, drying and spray drying. This paper reviews studies on energy efficiency improvement measures including WHR practices applied to the ceramic sector. This focuses on technologies and strategies which have significant potential to promote energy savings and carbon emissions reduction. The measures have been grouped into three main categories: (i) equipment level; (ii) plant level; and (iii) outer plant level. Some examples include: (i) high efficiency burners; (ii) hot air recycling from kilns to other processes and installation of heat exchangers; and (iii) installation of gas turbine for combined heat and power (CHP). It is observed that energy efficiency solutions allow savings up to 50–60% in the case of high efficiency burners; 15% energy savings for hot air recycling solutions and 30% in the when gas turbines are considered for CHP. Limitations to the implementation of some measures have been identified such as the high investment costs associated, for instance, with certain heat exchangers as well as the corrosive nature of certain available exhaust heat.

Los aisladores, en su operación diaria, están sometidos a la acción del medio ambiente y de su propia explotación, entendiéndose entre estas últimas las tensiones a la frecuencia del sistema y las sobretensiones que se originan por diferentes causas. En el caso del medio ambiente son dos factores fundamentales los que provocan que el aislador vaya perdiendo sus características aislantes: la acumulación de partículas contaminantes sobre la superficie de los mismos que cuando es humedecida por lluvias ligeras o niebla llega a ser conductora, a tal grado que se establece un arco de corriente, o descarga, entre la estructura que soporta los aisladores y los conductores, dañando a todo el conjunto y ocasionando cortes o interrupciones de la transmisión o distribución de energía ocasionando problemas de confiabilidad del servicio , por otro lado, las partes metálicas de los aisladores son afectadas por problemas de corrosión afectando sus características mecánicas. Los usuarios industriales demandan servicios de alta confiabilidad, que no sólo cumplan con ciertos rangos de tensión y frecuencia sino que también ofrezcan una continuidad en el servicio; entre los procesos que más son afectados por los cortes en el servicio están los de industrialización automática, debido a que son cada día más sensibles pudiendo alterar un proceso con una mínima interrupción en el servicio y ocasionando pérdidas millonarias. Determinar cuando tomar acciones correctivas para prever los fallos transitorios o permanentes en los aisladores de alta tensión ha sido un problema de las empresas del sector eléctrico por muchos años; en el caso de la contaminación, la solución ha estado hacia la sustitución del aislamiento o la ejecución de lavados periódicos del mismo, a veces sin ningún criterio técnico, lo que demanda una mano de obra considerable. Para el caso de la corrosión o de la destrucción parcial o total del aislamiento por las sobretensiones, las empresas no tienen más remedio que la sustitución del aislamiento cuando ocurre la falla, de manera general, o lo que se conoce como aplicación del mantenimiento correctivo. En los últimos años este problema ha tomado más importancia como consecuencia de la libre competencia de las empresas del sector eléctrico, ya que se necesita una optimización de las mismas y por ende una reducción de los costos de mantenimiento y mano de obra. El presente trabajo trata de exponer la relación estrecha que existe entre aislamiento y confiabilidad a partir de los nuevos paradigmas que se presentan en la actividad de mantenimiento, los cuales ofrecen algunos cambios interesantes en el entorno hasta ahora visto en esta dirección.

En el presente trabajo se realiza un estudio sobre la influencia que tiene el uso conjunto de la nanosílice y la ATH como cargas en la goma de silicona vulcanizada a temperatura ambiente que se emplea actualmente en el aislamiento externo para cubrir aisladores de porcelana o vidrio. Este estudio se realiza comparando recubrimientos de silicona vulcanizada a temperatura ambiente que contienen como cargas conjuntamente nanosílice y ATH con otros recubrimientos que contienen estas cargas de manera independiente. Dicha comparación se realiza en cuanto a la resistencia a la erosión, la limitación de las corrientes de fuga en condiciones de niebla salina y la pérdida y recuperación de la hidrofobicidad. Los resultados de este trabajo muestran un mejor desempeño de los recubrimientos que contienen conjuntamente como cargas la nanosílice y la ATH que los recubrimientos que las contienen de manera independiente.A study about the influence of joint use of nanosilica and ATH as fillers on room temperature vulcanized silicone rubber used in the outdoor insulation is carried out. This study is made by comparison between room temperature vulcanized silicone rubber coating with nanosilica and ATH as simultaneous fillers and room temperature vulcanized silicone rubber coating with nanosilica and ATH as independents fillers. The parameters of this comparison are: erosion resistance, circulation of leakage currents under salt fog conditions and hydrophobicity loss. The results of this work show a better development of room temperature vulcanized silicone rubber coating with nanosilica and ATH as simultaneous fillers than room temperature vulcanized silicone rubber coating with nanosilica and ATH as independents fillers.

Abstract Gorlin's syndrome is an autosomal dominant disorder, mainly characterized by the presence of multiple and early-onset basal cell carcinomas, odontogenic keratocysts and palmoplantar pits. We describe the case of a patient with clinical and imaging features of Gorlin syndrome, and highlight the role of dermoscopy in the early detection of basal cell carcinomas. In addition, we discuss the dermoscopic features of palmar pits.

Las anemias hemolíticas autoinmunes son las caracterizadas por la destrucción de los hematíes debida a la producción de autoanticuerpos por el paciente, dirigidos contra sus propios antígenos eritrocitarios. La asociación con enfermedad inflamatoria del intestino está descrita, pero no es de las asociaciones más frecuentes. Se presenta un caso de una paciente de 64 años de edad, que acude por diarreas y decaimiento, aparecen evolutivamente durante su ingreso lesiones ulceradas orales y perianales. Los exámenes complementarios mostraron una anemia hemolítica Coombs positiva. Los estudios endoscópicos del tubo digestivo, mostraron ulceración continua de todo el colon desde el ciego hasta el ano y pérdida de las austras, imagenológicamente se hizo evidente el aumento de tamaño del bazo en el curso de la hemólisis. Recibió tratamiento con esteroides y mesalazina por vía oral, desaparecieron las manifestaciones de hemólisis extravascular y mejoró la sintomatología digestiva. Se concluyó histológicamente como una enfermedad inflamatoria intestinal tipo colitis ulcerosa.

Background: Mediterranean spotted fever is a zoonosis endemic in the Mediterranean region. The microorganism Rickettsia conorii is responsible for the disease due to its angiotropism for endothelial cells. It produces host cell necrosis, thrombosis, and organ dysfunction. Ophthalmologic manifestations are rare. Findings: The authors describe the case of a 55-year-old female with Mediterranean spotted fever who developed localized retinal vasculitis with associated macular edema. Treatment with intravitreal triamcinolone allowed a significant recovery of visual acuity. Conclusion: Ophthalmological symptoms in these patients should be emphasized because there can be severe ocular complications with a potentially irreversible loss of visual acuity.

The crystal structure of the polymeric spin crossover compound Fe(3,4-dimethyl-pyridine)2[Ag(CN)2]2 has been solved and its temperature dependence followed by means of single-crystal and powder X-ray diffraction. This compound presents a two-step spin transition with relatively abrupt steps centred at ca. 170 K and 145 K and a plateau at around 155 K. The origin of the two-step transition is discussed in light of these structural studies. The observations are compatible with a mostly disordered state between the two steps, consisting of mixing of high-spin and low-spin species, while weak substructure reflections in the mixed phase could indicate some degree of long-range order of the high-spin and low-spin sites.

La integración de la energía eólica en los sistemas eléctricos puede provocar problemas de estabilidad ligados fundamentalmente a la variación aleatoria del viento; conocer el Límite de Potencia Eólica (LPE) que puede insertarse en la red sin que esta pierda la estabilidad es un aspecto de extrema importancia, para lo cual se han implementado diferentes métodos de cálculo, entre los cuales se encuentran aquellos que tienen en consideración las restricciones del sistema en estado estacionario, como por ejemplo el que se fundamenta en un análisis de simulaciones de flujo continuado. En este trabajo se aplica dicho método en un micro sistema eléctrico que puede formarse a partir de un sistema al trabajar en isla, siendo el objetivo principal probar el método en un sistema débil y aislado de la red principal. Para la corrida de las simulaciones se usa el software libre PSAT, el cual utiliza de plataforma el MatLab.The wind power insertion in the power system is an important issue and can create some instability problems in voltage and system frequency due to stochastic origin of wind. Know the Wind Power Limit that can insert in an electric grid without losing stability is a very important matter. Existing in bibliography a few methods for calculation of wind power limit, some of them are based in static constrains, an example is a method based in a continuation power flow analysis. In the present work the method is applied in an electric micro system formed when the system is disconnected of the man grid, the main goal was prove the method in a weak and island network. The software used in the simulations was the Power System Analysis Toolbox (PSAT).

En este artículo, se propone un modelo conceptual para el desarrollo de la capacidad de absorción (CAPAB) en organizaciones de sectores con media-baja intensidad tecnológica, a partir de 10 modelos internacionales y la experiencia cubana sobre este tema. Se sustenta la CAPAB como competencia dinámica referida a la identificación/reconocimiento, adquisición/integración/configuración, aplicación/explotación de conocimiento externo relevante. Se exponen avances en la comprensión de los elementos inductores y procesos para el desarrollo de la CAPAB y se exploran aspectos subvalorados en la literatura como: actitud estratégica, concepción de diferentes tipos de conocimiento, así como las innovaciones de proceso y organizacionales. Se establecen los componentes esenciales para las organizaciones de sectores con media-baja intensidad tecnológica, a partir de los cuales se determina un índice empírico para evaluar tal competencia en la empresa de grupos electrógenos y servicios eléctricos, GEYSEL y se analizan los resultados obtenidos.This paper proposes a new model for analysis of the components of absorptive capacity (CAPAB) in organization sat medium-low technological intensity sectors through ten international models and the Cuban experiences concerning to this matter. It is suggested that CAPAB as a dynamic competence referred to identification/recognition, acquisition/ integration/configuration, application/exploitation of relevant external knowledge. The article shows advances on the driver elements and process for the CAPAB understanding by exploring features under valuables in the literature as: strategic attitude, the conception of different relevant types of knowledge, as the process and organizational innovations. It is established the essentials components for organizations at medium-low technological intensity sectors, in order to determine an empiric index to evaluate those competence, at the enterprise GEYSEL and It is analysed the results.

La generación fotovoltaica con sistemas conectados a red eléctrica en el esquema de generación distribuida, es una alternativa que contribuye con beneficios a la reducción del pico de demanda vespertina, a la disminución de pérdidas por distribución; siendo una opción en el desarrollo de las inversiones que incrementan la capacidad de la red de distribución en un escenario a gran escala, pudiendo sustituir inversiones en capacidad de generación y transmisión. Esta idea supone la penetración de la tecnología fotovoltaica aumentando su presencia en la generación eléctrica.Los resultados presentados forman parte de la elaboración de los estudios de prefactibilidad para determinar la incidencia de la radiación solar, considerando la ordenación del territorio a partir de las condiciones de la ubicación geográfica, haciendo la selección de los sitios adecuados por las características de potencial solar, eficiencia de la infraestructura eléctrica y disponibilidad del espacio para la introducción de los sistemas fotovoltaicos.The photovoltaic generation with connected systems to electric grid in the outline of distributed generation, is an alternative that contributes with benefits to the reduction of the pick of evening demand, to the decrease of losses for distribution; being an option in the development of the investments that it increase the capacity of the distribution grid in a scenario to great scale, being able to substitute investments in generation capacity and transmission. This idea supposes the penetration of the photovoltaic technology increasing in the electric generation.The presented results are part of the elaboration of the studies of feasibility to determine the incidence of the solar radiation, considering the ordination of the territory starting from the conditions of the geographical location, making the selection of the places adapted by the characteristics of solar potential, the electric efficiency, infrastructure and readiness of the space for the introduction of the photovoltaic systems.

La generación fotovoltaica con sistemas conectados a red eléctrica en el esquema de generación distribuida, es una alternativa que contribuye con beneficios a la reducción del pico de demanda vespertina, a la disminución de pérdidas por distribución; siendo una opción en el desarrollo de las inversiones que incrementan la capacidad de la red de distribución en un escenario a gran escala, pudiendo sustituir inversiones en capacidad de generación y transmisión. Esta idea supone la penetración de la tecnología fotovoltaica aumentando su presencia en la generación eléctrica.Los resultados presentados forman parte de la elaboración de los estudios de prefactibilidad para determinar la incidencia de la radiación solar, considerando la ordenación del territorio a partir de las condiciones de la ubicación geográfica, haciendo la selección de los sitios adecuados por las características de potencial solar, eficiencia de la infraestructura eléctrica y disponibilidad del espacio para la introducción de los sistemas fotovoltaicos.Palabras clave: The photovoltaic generation with connected systems to electric grid in the outline of distributed generation, is an alternative that contributes with benefits to the reduction of the pick of evening demand, to the decrease of losses for distribution; being an option in the development of the investments that it increase the capacity of the distribution grid in a scenario to great scale, being able to substitute investments in generation capacity and transmission. This idea supposes the penetration of the photovoltaic technology increasing in the electric generation.The presented results are part of the elaboration of the studies of feasibility to determine the incidence of the solar radiation, considering the ordination of the territory starting from the conditions of the geographical location, making the selection of the places adapted by the characteristics of solar potential, the electric efficiency, infrastructure and readiness of the space for the introduction of the photovoltaic systems.Key words:

La integración de la energía eólica en los sistemas eléctricos puede provocar problemas de estabilidad ligados fundamentalmente a la variación aleatoria del viento; conocer el Límite de Potencia Eólica (LPE) que puede insertarse en la red sin que esta pierda la estabilidad es un aspecto de extrema importancia, para lo cual se han implementado diferentes métodos de cálculo, entre los cuales se encuentran aquellos que tienen en consideración las restricciones del sistema en estado estacionario, como por ejemplo el que se fundamenta en un análisis de simulaciones de flujo continuado. En este trabajo se aplica dicho método en un micro sistema eléctrico que puede formarse a partir de un sistema al trabajar en isla, siendo el objetivo principal probar el método en un sistema débil y aislado de la red principal. Para la corrida de las simulaciones se usa el software libre PSAT, el cual utiliza de plataforma el MatLab. The wind power insertion in the power system is an important issue and can create some instability problems in voltage and system frequency due to stochastic origin of wind. Know the Wind Power Limit that can insert in an electric grid without losing stability is a very important matter. Existing in bibliography a few methods for calculation of wind power limit, some of them are based in static constrains, an example is a method based in a continuation power flow analysis. In the present work the method is applied in an electric micro system formed when the system is disconnected of the man grid, the main goal was prove the method in a weak and island network. The software used in the simulations was the Power System Analysis Toolbox (PSAT).

The olive tree with its fruit, the olive, has been throughout history a culture whose importance has generated a widespread culture along the Mediterranean Sea. Since the days of ancient Egypt until today, its transformation to the consumption of olives, table olives or vegetable fat, has evolved hand in hand with contemporary techniques known. As for obtaining olive oil, fruit or the pressing of the pulp obtained after milling, is a critical point in its manufacture. This process is the goal of this communication which will present a technical analysis of an oil press. This is expected to achieve greater depth of knowledge of the techniques employed in the sector of olive oil.

Desde la dinastía Song en Oriente Medio, alrededor del siglo XII, los molinos de viento han sido protagonistas en la transformación de la energía eólica para ciertos trabajos mecánicos, como la extracción del agua o la molienda del cereal. En consecuencia, a lo largo de la historia se ha investigado sobre esta clase de patrimonio industrial desde diversos enfoques, aunque no siempre desde el punto de vista de la ingeniería. La metodología seguida tras realizar un inventario de los 89 ingenios eólicos ha sido obtener su modelo 3D, caracterizando el viento y finalizando con el estudio mecánico de sus principales parámetros de funcionamiento. El resultado ha sido su idoneidad para trabajar a bajas velocidades produciendo un par elevado gracias a la superficie expuesta del velamen al viento, y que los molinos de viento de Cádiz y Huelva presentaban un rendimiento eólico mayor al estar mejor diseñados que los de Almería.

En el presente artículo se analiza en detalle un ejemplo del patrimonio industrial minero del antiguo distrito minero de Linares- La Carolina (Jaén, España), como es una cabria de mampostería con su castillete metálico, utilizada en la extracción del mineral de plomo, concretamente de galena o sulfuro de plomo. En particular, se ha realizado el modelado tridimensional con ayuda de software paramétrico gracias a técnicas empíricas de cada uno de los elementos que componen el conjunto. Asimismo, una vez obtenido el modelo 3D, se ha realizado un análisis funcional mediante técnicas de Ingeniería Asistida por Ordenador, basadas en el análisis tensional y el análisis de desplazamientos, comprobando que las mayores concentraciones de tensiones se producen en la parte media e inferior de los muros, que los mayores valores de tensión se producen en los alrededores de los huecos de los muros, y que la mayor concentración de desplazamientos de la cabria de mampostería se encuentran en los muros en la parte media y superior, y del castillete en las correas de la cubierta.

Se aborda la necesidad de formar las concepciones sobre el tratamiento de la innovación como resultado del proceso continuo de aprendizaje organizacional devenido de la integración y re-configuración de conocimientos impregnados en personas, procesos, sistemas y prácticas de gestión; como plataforma para el estudio de los mecanismos desde los cuales se construye e incrementa la capacidad de absorción. Se propone un modelo conceptual para explicar la capacidad de innovar en una organización, estableciendo sus componentes esenciales, determinándose un conjunto de variables que permiten construir indicadores empíricos para evaluar tal capacidad y su impacto en el nivel de desempeño organizacional. La aplicación se desarrolla en la Generación Distribuida en base a Grupos Electrógenos de Fuel, con insuficiencias en la actitud estrategia hacia la innovación, el aprendizaje organizacional y el entorno, que limitaban la asimilación de las tecnologías adquiridas en los años 2005-2008. In this paper are made considerations about the need to form conceptions respect to treatment of innovation as a result of an organizational learning process become continuous integration and re-configuration ofembedded knowledge in people, processes, systems and the practices of management, as platform to study the mechanisms through which the absorptive capacity is built and increased. It is proposed a conceptualmodel to explain the innovation capability at a company and establish its essential components, by identifying a set of variables to construct empirical measures to evaluate such capacity and its impact on thelevel of organizational performance. The research was developed at the Cuban´s distributed generation by fuel oil engines´ plants; these organizations presented insufficiency with strategic attitude to innovation,learning and environment, which limited the assimilation of the acquired technologies on years 2005-2008.

Modified nucleosides have the potential to inhibit DNA polymerases for the treatment of viral infections and cancer. With the hope of developing potent drug candidates by the modification of the 2',4'-position of the ribose with the inclusion of a bridge, efforts were focused on the inhibition of Taq DNA polymerase using quantitative real time PCR, and the results revealed the significant inhibitory effects of 2',4'-bridged thymidine nucleoside on the polymerase. Study on the mode of inhibition revealed the competitive mechanism with which the 2',4'-bridged thymidine operates. With a Ki value of 9.7 ± 1.1 μM, the 2',4'-bridged thymidine proved to be a very promising inhibitor. Additionally, docking analysis showed that all the nucleosides including 2',4'-bridged thymidine were able to dock in the active site, indicating that the substrate analogs reflect a structural complementarity to the enzyme active site. The analysis also provided evidence that Asp610 was a key binding site for 2',4'-bridged thymidine. Molecular dynamics (MD) simulations were performed to further understand the conformational variations of the binding. The root-mean-square deviation (RMSD) values for the peptide backbone of the enzyme and the nitrogenous base of the inhibitor stabilized within 0.8 and 0.2 ns, respectively. Furthermore, the MD analysis indicates substantial conformational change in the ligand (inhibitor) as the nitrogenous base rotated anticlockwise with respect to the sugar moiety, complemented by the formation of several new hydrogen bonds where Arg587 served as a pivot axis for binding formation. In conclusion, the active site inhibition of Taq DNA polymerase by 2',4'-bridged thymidine suggests the potential of bridged nucleosides as drug candidates.

Technological advances for improving supply chain efficiency present three key challenges for managing goods: tracking, tracing and monitoring (TTM), in order to satisfy the requirements for products such as perishable goods where the European Legislations requires them to ship within a prescribed temperature range to ensure freshness and suitability for consumption. The proposed system integrates RFID for tracking and tracing through a distributed architecture developed for heavy goods vehicles, and the sensors embedded in the SunSPOT platform for monitoring the goods transported based on the concept of the Internet of Things. This paper presents how the Internet of Things is integrated for improving terrestrial logistics offering a comprehensive and flexible architecture, with high scalability, according to the specific needs for reaching an item-level continuous monitoring solution. The major contribution from this work is the optimization of the Embedded Web Services based on RESTful (Web of Things) for the access to TTM services at any time during the transportation of goods. Specifically, it has been extended the monitoring patterns such as observe and blockwise transfer for the requirements from the continuous conditional monitoring, and for the transfer of full inventories and partial ones based on conditional queries. In definitive, this work presents an evolution of the previous TTM solutions, which were limited to trailer identification and environment monitoring, to a solution which is able to provide an exhaustive item-level monitoring, required for several use cases. This exhaustive monitoring has required new communication capabilities through the Web of Things, which has been optimized with the use and improvement of a set of communications patterns.

En el presente trabajo se realiza un estudio sobre la influencia que tiene agregar como carga nanosílice a la goma de silicona vulcanizada a temperatura ambiente (RTV SR, por sus siglas en inglés) que es empleada para cubrir aisladores de vidrio o de porcelana. Con este objetivo se observó la dispersión de la nanosílice en la RTV SR por medio de microscopía electrónica de barrido (MEV, por sus siglas en inglés), se midió la permitividad de la RTV SR con y sin nanosílice para varias frecuencias y se evaluó la influencia que tiene la nanosílice en la resistencia a la erosión. Además fueron medidas las corrientes de fuga durante ensayos de niebla salina a aisladores de vidrio pintados con estos recubrimientos, analizando también la pérdida de hidrofobicidad que ocurre durante el ensayo y su recuperación una vez finalizado el mismo.The present research work carries out a study on the influence of nanosilica on room temperature vulcanized silicone rubber (RTV SR) used to coat insulators. Considering this objective, the dispersion of nanosilica was observed by means of scanning electron microscopy (MEV), the permittivity of the room temperature vulcanized silicone rubber was measured with and without nanosilica for different frequencies and the influence of nanosilica in erosion resistance. Leakage currents were also measured during salt spray tests to glass insulators covered with these coatings; the loss of hidrophobicity during the test was also measured and its recovery was analyzed the test was finished.

The development of computer tools in the last decade is indisputable evidence that is allowing perceive reality more fully through different techniuqes, such as the Augmented Reality (AR). Taking as a starting point Augmented Reality technology, this study seeks to support the implementation of milling heritage knowledge and its application to the recovery of the Windmills of Andalusia (Spain). In this way, ensures that the visitor gets a more pleasant experience when interpreting the remains and the operation of these windmills' owm pre-industrial archaeology.

El empleo de las técnicas CAD (Computer-Aided Design) es una práctica normal y de carácter obligatorio si se considera la tarea de recuperación gráfica que conlleva cualquier estudio de arqueología industrial. Por tanto, se deduce la importancia que un correcto modelado CAD tiene en los diferentes estudios y análisis, como por ejemplo, los de simulación de un proceso físico mediante el método de elementos finitos. En este sentido, la comunicación pretende analizar aspectos críticos en las superficies y mallado del modelo 3D que se presenta en la tarea investigadora de la recuperación gráfica de cualquier ejemplo de patrimonio industrial, como por ejemplo, los molinos de viento de la Comunidad de Andalucía (España)

At many countries there is great areas where wind resource are very grateful but the electrical network isweak. At these areas the network capacity could be a limit to exploitation of wind resource.There are twomain problems related with the associated power of wind resurge and the network weak. First, it is relatedwith steady state voltage level: when demand is low the voltage level could increase more than permittedlimits if the energy production is high. The second problem is related with flicker voltage: the wind resourceis not constant and the disconnection of the wind turbines could cause flicker voltage more than permittedlimits.In Cuban electric system the presence of weak network is normally and different problems likehurricanes or work this electric system require to divide on electric subsystems with possible highcontribution of wind generation. The preliminary analysis at one zone of Cuban´s archipelago from the pointof view of wind penetration is presented in this paper.

Linear oligomerization of 3,5-dimethyl benzyl alcohol is induced by a montmorillonite clay (Tonsil Optimum Extra), producing 1,3,5,7-tetramethyl-9,10-dihydro-anthracene, which, by loss of protons results in the product 1,3,5,7-tetramethylanthracene. It was also found that the compounds 4-(3´,5´-dimethylbenzyl)-1,3,5,7-tetramethyl-9,10-dihydroanthracece and 4-(3´,5´-dimethylbenzyl)-1,3,5,7-tetra-methylanthracene were formed from 1,3,5,7-tetramethyl-9,10-dihydroanthracene. 1,3,5,7-Tetramethylanthryl radical cation was formed from 1,3,5,7-tetramethyl-9,10-dihydroanthracene; it was characterized by Electronic Paramagnetic Resonance (EPR). On the other hand, a theoretical analysis was performed, allowing the rationalization of the observed products and some of the key reaction steps.

Since the first decades of the twentieth century, Portugal has affirmed itself as an emigration country. This social, political, economic and demographic phenomenon has consequences, which have always been approached in a general way, neglecting the personal side and identity aspects that the displacement causes at an individual and family level. In long duration emigration, there is usually a paradoxical feeling of non-belonging/belonging to two spaces. On the one hand, already integrated in the new reality, the individual feels that to a certain extent they belong to the new space. However, in their identity memory, the culture and way of life of their nationality, region or place still exists. This dilemma of (non)belonging is relatively abstract to convey to students, when we work the demographic phenomenon. We used a recent film—The Golden Cage, released by the son of Portuguese emigrants—where this feeling of belonging is represented, under ‘the cover’ of a comedy. We showed the film to a group of Demography and Sociology students and had them explore this phenomenon. The results were extremely positive.

Diesel engine generator (RM) is one of the most used technologies on distributed generation (DG). The presence of RM, no manner its operation form need an analysis about differents problems: one of them is related with power quality (PQ). First results obained inside one study directed to obtain answers about differents perturbations for the RM presence like shortcircuit and voltage variation on RM termianls and rejected charge are presented in this paper.

En muchas industrias, edificios, empresas y servicios por razones productivas, emergentes o de confiablidad, es necesario generar energía eléctrica independientemente del Sistema Eléctrico Nacional. En otros casos se necesitan plantas de generación de energía eléctrica que puedan trabajar de forma aislada alimentando un circuito determinado. Para realizar la selección más económica y eficiente de la capacidad a instalar se debe tomar en consideración no sólo el comportamiento del sistema donde se va a insertar la unidad, sino también, las características operacionales del generador ante las fluctuaciones de la carga, sus límites operacionales y la estabilidad resultante. Este trabajo presenta un software que permite realizar la selección más adecuada considerando la curva de capacidad y la estabilidad del generador ante las particularidades del sistema. Con su aplicación es posible reducir los gastos y las pérdidas económicas debidas a una selección inapropiada. Como caso se presenta su aplicación a una planta de una fábrica de envases de alimentos. In many industries, buildings and services is necessary to employ independent power plants to supply the electric power to a particular system. In other cases, islanded operation is desired due to several specific situations. In order to realize the most efficient, economic and adequate selection of the generator capacity is necessary to consider not only the systems load characteristic, also is necessary to know the limits of capabilities and the resultant stability of the power generator. This paper presents a software that allows to select the adequate generator, expose the operating limits and the resulting stability in fluctuating load condition. With its application is possible to reduce economic losses and the costs due to an impropriated generator selection with an oversized o sub utilized machine. As a case a 2500 kVA power plant is analyzed.

IntroductionWhile short-term surgical outreach trips improve access to care in low- and middle-income countries (LMIC), there is rising concern about their long-term impact. In response, many organizations seek to incorporate capacity building programs into their outreach efforts to help strengthen local health systems. Although leading organizations, like the World Health Organization (WHO), advocate for this approach, uniform guidelines are absent.MethodsWe performed a systematic review, using search terms pertaining to capacity building guidelines during short-term surgical outreach trips. We extracted information on authorship, guideline development methodology, and guidelines relating to capacity building. Guidelines were classified according to the Global-QUEST framework, which outlines seven domains of capacity building on surgical outreach trips. Guideline development methodology frequencies and domain classifications frequencies were calculated; subsequently, guidelines were aggregated to develop a core guideline for each domain.ResultsA total of 35 studies were included. Over 200 individual guidelines were extracted, spanning all seven framework domains. Guidelines were most frequently classified into Coordination and Community Impact domains and least frequently into the Finance domain. Less than half (46%) of studies collaborated with local communities to design the guidelines. Instead, guidelines were predominantly developed through author trip experience.ConclusionAs short-term surgical trips increase, further work is needed to standardize guidelines, create actionable steps, and promote collaborations in order to promote accountability during short-term surgical outreach trips.

En el presente trabajo se realiza un estudio sobre la influencia que tiene agregar como carga nanosílice a la goma de silicona vulcanizada a temperatura ambiente (RTV SR, por sus siglas en inglés) que es empleada para cubrir aisladores de vidrio o de porcelana. Con este objetivo se observó la dispersión de la nanosílice en la RTV SR por medio de microscopía electrónica de barrido (MEV, por sus siglas en inglés), se midió la permitividad de la RTV SR con y sin nanosílice para varias frecuencias y se evaluó la influencia que tiene la nanosílice en la resistencia a la erosión. Además fueron medidas las corrientes de fuga durante ensayos de niebla salina a aisladores de vidrio pintados con estos recubrimientos, analizando también la pérdida de hidrofobicidad que ocurre durante el ensayo y su recuperación una vez finalizado el mismo. The present research work carries out a study on the influence of nanosilica on room temperature vulcanized silicone rubber (RTV SR) used to coat insulators. Considering this objective, the dispersion of nanosilica was observed by means of scanning electron microscopy (MEV), the permittivity of the room temperature vulcanized silicone rubber was measured with and without nanosilica for different frequencies and the influence of nanosilica in erosion resistance. Leakage currents were also measured during salt spray tests to glass insulators covered with these coatings; the loss of hidrophobicity during the test was also measured and its recovery was analyzed the test was finished.

BackgroundThe burden of traumatic musculoskeletal injuries falls greatest on low- and middle-income countries (LMICs). To help address this burden, organizations host over 6,000 outreach trips annually, 20% of which are orthopaedic. Monitoring post-surgical outcomes is critical to ensuring care quality; however, the implementation of such monitoring is unknown. The purpose of this review is to identify published follow-up practices of short-term orthopaedic surgery outreach trips to LMICs.MethodsWe completed a systematic review of Pubmed, Web of Science, EMBASE, and ProQuest following PRISMA guidelines. Follow-up method, rate, duration, and types of outcomes measured along with barriers to follow-up were collected and reported.ResultsThe initial search yielded 1,452 articles, 18 of which were eligible. The mean follow-up time was 5.4 months (range: 15 days-7 years). The mean follow-up rate was 65.8% (range: 22%-100%), the weighted rate was 57.5%. Fifteen studies reported follow-up at or after 3 months while eight studies reported follow-up at or after 9 months. Fifteen studies reported follow-up in person, three reported follow-up via phone call or SMS. Outcome reporting varied among mortality, complications, and patient-reported outcomes. The majority (75%) outlined barriers to follow-up, most commonly noting transportation and costs of follow-up to the patient.ConclusionsThere is minimal and heterogeneous public reporting of patient outcomes and follow-up after outreach trips to LMICs, limiting quality assessment and improvement. Future work should address the design and implementation of tools and guidelines to improve follow-up as well as outcome measurement to ensure provision of high-quality care.

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Pylephlebitis is defined as septic thrombophlebitis of the portal vein. It is a rare but serious complication of an intraabdominal infection, more commonly diverticulitis and appendicitis. It has an unspecific clinical presentation and the diagnosis is difficult. The authors report a case of a 21-year-old man with acute appendicitis complicated by pylephlebitis. The diagnosis was made with contrast enhanced CT.

La integración de la energía eólica en los sistemas eléctricos puede provocar problemas de estabilidad ligados fundamentalmente a la variación aleatoria del viento y que se reflejan en la tensión y la frecuencia del sistema. Por lo que conocer el Límite de Potencia Eólica (LPE) que puede insertarse en la red sin que esta pierda la estabilidad es un aspecto de extrema importancia, en el cual se han realizando métodos de cálculo para encontrar dicho límite. Estos métodos se desarrollan teniendo en cuenta las restricciones del sistema en estado estacionario, en estado dinámico o ambos. En el siguiente trabajo se desarrolla un método para el cálculo de LPE teniendo en cuenta las restricciones en estado estacionario del sistema. El método propuesto se basa en un análisis de flujo continuado, complementado con el método de Producción Mínima de Potencia Activa, desarrollado en la bibliografía. Se prueba en el sistema eléctrico de la Isla de la Juventud, Cuba y se usa elsoftware libre PSAT para la realización de estos estudios. The wind power insertion in the power system is an important issue and can create some instability problems in voltage and system frequency due to stochastic origin of wind. Know the Wind Power Limit is a very importantmatter. Existing In bibliography a few methods for calculation of wind power limit. The calculation is based in static constrains, dynamic constraints or both. In this paper is developed a method for the calculation of wind power limit using some adjust in the continuation power flow, and having into account the static constrains. The method is complemented with Minimal Power Production Criterion. The method is proved in the Isla de la Juventud Electric System. The software used in the simulations was the Power System Analysis Toolbox (PSAT).

La integración de la energía eólica en los sistemas eléctricos puede ocasionar problemas de estabilidad ligados fundamentalmente a la variación aleatoria del viento, lo que provoca que la tensión en el nodo de conexión varíe. Si el sistema al que se conecta es débil esta variación tiene una mayor influencia. Otro factor importante es el tipo de tecnología utilizada, ya que losaerogeneradores de velocidad fija conectados directamente a la red tienen un gran consumo de potencia reactiva, esta puede ser compensada utilizando diferentes dispositivos (banco de condensadores, SVC o STATCOM). Los aerogeneradores de velocidad variable poseen un convertidor que controla el consumo de reactivo para mantener la tensión en el nodo de conexión lomás estable posible. En este trabajo se hace una comparación entre los diferentes tipos de tecnologías de aerogeneradores utilizadas y su impacto en el límite de generación eólica cuando el sistema se va debilitando. The insertion of wind energy into electric network may provoke stability problems due to stochastic character of wind. The variation in the wind causes voltage variation in the Point of Common Coupling (PCC). In a weakest system that variation is high. Another important factor is wind turbine technology. The use of grid-connected fixed speed wind generator introduces a great consumption of reactive power that can be compensated using different devices as capacitors bank or static var compensator (SVC or STATCOM). In the other hand the variable speed wind turbine have anelectronic converter to control the reactive consumption to maintain the PCC voltage more stable. In this paper a comparison between the different types of wind turbines technology is show. It’s analyzing the impact in wind power limit for different wind turbine technologies in a weak system.

Entrevista a Bruno Bravo.