330 research outputs found

    Does international patent collaboration have an effect on entrepreneurship?

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    .Entrepreneurship is one of the main pillars of growth in any economy. Achieving a high rate of entrepreneurship in a region has become the priority objective of governments and firms. However, in many cases, new firm creation is conditioned by relations or collaboration in innovation with agents from other countries. Previous literature has analyzed the mechanisms that foster entrepreneurship. This paper attempts to shed light on the influence of international patent collaboration (IPC) on entrepreneurial activity at country level taking into account the timing of this relationship. An empirical study is proposed to verify whether IPC leads to greater entrepreneurship and to analyze the gestation period between international patenting actions and firm creation. Using the Generalized Method of Moments, the two hypotheses proposed were tested in a data panel of 30 countries for the period 2005–2017. Results show the influence of IPC in promoting entrepreneurship in the same year, but especially in the following year. The study offers implications for entrepreneurs and public agents. IPC affects the integration and interaction of international agents in a country, favors the production of new knowledge, and increases positive externalities in a territory. All this facilitates the creation of new companies with a high innovative component.S

    Uniform, luminescent Eu:LuF3 nanoparticles

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    A simple procedure for the synthesis of orthorhombic, uniform, LuF3 particles with two different morphologies (rhombus- and cocoon-like) and nanometer and sub-micrometer size, respectively, is reported. The method consists in the aging, at 120 °C for 2 h, a solution containing [BMIM]BF4 ionic liquid (0.5 mL) and lutetium acetate (in the case of the rhombi) or lutetium nitrate (in the case of the cocoons) (0.02 M) in ethylene glycol (total volume 10 mL). This synthesis method was also adequate for the synthesis of Eu3+-doped LuF3 particles of both morphologies, whose luminescence properties were investigated in detail. The experimental observations reported herein suggest that these materials are suitable phosphors for optoelectronic as well as in vitro biotechnological applications.MEC MAT2012-34919Junta de Andalucía JA FQM 06090CSIC 201460E00

    Mathematical modeling of neuronal connexin-36 channels

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    Neurotransmission through electrical synapses play an important role in the spike synchrony among neurons and oscillation of neuron networks. Connexin36 (Cx36) is the principal gap junction protein of electrical synapses between inhibitory interneurons in vertebrates. Coupling strength between coupled neurons is modulated, among other factor, by the voltage difference between cell interiors, termed transjunctional voltage (Vj), in a complex manner; with the Vj gradient junctional conductance of Cx36 channels first increases instantaneously (+ 20% for + 100 mV) and then it decreases slowly to half for a similar range of Vj. The significance of this regulation by voltage, a stimulus always presents and changing, in the firing properties of coupled neurons is unknown

    Bacterias diazotroficas y solubilizadoras de fósforo aisladas de las especies forestles altoandinas colombianas Weinmannia tomentosa y Escallonia myrtilloides

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    Encenillo (Weinmannia tomentosa Lf) and pagoda (Escallonia myrtilloides Lf) are dominant native tree species that can be found in the forests of the complex Andean Guerrero (Cundinamarca, Colombia). Forty two phosphorus-solubilizing bacteria and 125 nitrogen-fixing strains were isolated from the rhizosphere of these trees, out of which the microbial strains presenting the best five results of dissolution of phosphate and acetylene reduction by plant species were selected. The diazotrophic strains selected were identified as close to Enterobacter gergoviae, Alcaligenes sp. (E13C and E12E strains), Enterobacter sp. (E14C.2 strain), Pseudomonas sp., Sphingomonas sp., Paenibacillus sp., Achromobacter sp., Flavobacterium adoratum, and Klebsiella pneumoniae, and as phosphate-solubilizingbacteria near to Pantoea agglomerans, Pantoea sp., Brevudimonas sp., Enterobacter sp. (E6C.1 strain), Burkholderia cepacia, Arthrobacter sp., Aeromicrobium sp., Corynebacterium sp., Pimelobacter sp. and Micrococcus sp. In order to perform preliminary in vivo tests with the chosen microorganisms, it was inoculated bacterial mixture to encenillo and pagoda seedlings and evaluated their longitudinal growth for three months under greenhouse conditions. The major averages were obtained with the inoculation of Enterobacter gergoviae and Pantoea sp. in encenillo seedlings (average increase of 51% and 57% greater than the controls without microbial inoculation and sterile molasses medium, respectively) and the mixture of all selected bacteria in pagoda (Stimulation of 16% and 32% compared to controls molasses and without bacterial inoculation, respectively). The results showed that all the combinations using microbial inocula significantly stimulated longitudinal growth (Duncan multiple range test P<0.05). The synergism shown by co-inoculation of diazotrophic bacteria and phosphate solubilizing bacteria indicate the potential of these microorganisms as plant growth promoters and biofertilizers.El encenillo (Weinmannia tomentosa L.f) y la pagoda (Escallonia myrtilloides L.f) son especies forestales nativas predominantes en bosques altoandinos del complejo Guerrero (Cundinamarca, Colombia). De la rizosfera de estos árboles se aislaron 42 bacterias solubilizadoras de fósforo y 125 fijadoras de nitrógeno, de las cuales se escogieron las cepas microbianas que presentaron los cinco mejores resultados de disolución de fosfato y reducción de acetileno por cada especie vegetal. Las cepas diazotróficas escogidas se identificaron como cercanas a Enterobacter gergoviae, Alcaligenes sp. (Cepas E12E y E13C), Enterobacter sp (cepa E14C.2), Pseudomonas sp., Sphingomonas sp., Paenibacillus sp., Achromobacter sp., Flavobacterium adoratum y Klebsiella pneumoniae; y como solubilizadoras de fósforo a Pantoea agglomerans, Pantoea sp., Brevudimonas sp., Enterobacter sp. (Cepa E6C.1), Burkholderia cepacia, Arthrobacter sp., Aeromicrobium sp., Corynebacterium sp., Pimelobacter sp. y Micrococcus sp. Se realizaron ensayos preliminares in vivo con los microorganismos escogidos y se inocularon diferentes combinaciones bacterianas en plántulas de encenillo y pagoda. Se evaluó el crecimiento longitudinal durante tres meses bajo condiciones de invernadero. Los mayores promedios se obtuvieron con la inoculación de Enterobacter gergoviae y Pantoea sp., en plántulas de encenillo (incremento promedio de 51% y 57% más que los controles sin ninguna inoculación microbiana y medio melaza estéril, respectivamente) y con la mezcla de todas las bacterias escogidas en pagoda (estimulación de 16% y 32%, con respecto a los controles melaza y sin inoculación bacteriana, respectivamente). Todas las combinaciones microbianas utilizadas estimularon significativamente el crecimiento longitudinal (prueba de Duncan P<0,05). El sinergismo mostrado por la co-inoculación de bacterias diazotróficas y solubilizadoras de fósforo indican el potencial de estos microorganismos como promotores de crecimiento vegetal y posibles biofertilizantes

    La técnica de Spaso para reducción de la luxación anterior de hombro.

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    Hemos revisado retrospectivamente los pacientes con luxación anterior de hombro que hemos tratado con la maniobra de reducción conocida como la técnica de Spaso. Hemos evaluado a 23 pacientes con luxación glenohumeral antero-inferior. En diecinueve casos era el primer episodio de luxación, mientras que cuatro casos correspondían a luxación recidivante. En todos los pacientes, menos en dos casos, se pudo conseguir la reducción de manera sencilla e indolora sin necesidad de medicación. La técnica consiste en disponer al paciente en decúbito supino, se coloca el miembro superior afectado, en extensión completa del codo y dirigido al cenit, se realiza tracción suave mientras se realiza una rotación externa del miembro. Presentamos esta técnica dada su sencillez, su fiabilidad, su reproducibilidad y su baja tasa de complicaciones.We have reviewed retrospectively a group of patients with previous traumatic dislocation of shoulder trea- ted with of Spaso maneuver. We have evaluated 23 patients with antero-inferior glenohumeral dislocation. In nineteen cases it was the first episode of dislocation, whereas four cases refered recurrent instability. In all patients, except in two cases, the reduction was simple and painless with no need of medication. The Spaso technique consists of arran- ging the patient in supine position, with the affected superior member, in complete extension of elbow, to the cenit, while traction is exerced, with mild external rotation of the arm. We presented this technique that we consider simple, safe and reproductible with a low rate of complications

    Rare earth based nanostructured materials: Synthesis, functionalization, properties and bioimaging and biosensing applications

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    Rare earth based nanostructures constitute a type of functional materials widely used and studied in the recent literature. The purpose of this review is to provide a general and comprehensive overview of the current state of the art, with special focus on the commonly employed synthesis methods and functionalization strategies of rare earth based nanoparticles and on their different bioimaging and biosensing applications. The luminescent (including downconversion, upconversion and permanent luminescence) and magnetic properties of rare earth based nanoparticles, as well as their ability to absorb X-rays, will also be explained and connected with their luminescent, magnetic resonance and X-ray computed tomography bioimaging applications, respectively. This review is not only restricted to nanoparticles, and recent advances reported for in other nanostructures containing rare earths, such as metal organic frameworks and lanthanide complexes conjugated with biological structures, will also be commented on.European Union 267226Ministerio de Economía y Competitividad MAT2014-54852-

    Connexin-36 protects against suddent infant death syndrome

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    The sudden infant death syndrome (SIDS) is the main cause of postneonatal infant death; however the etiology of SIDS remains ill defined. The hypothesis that SIDS, or a subset of SIDS, is due to an abnormal brainstem mechanism is one of the current leading hypotheses on SIDS etiology. The brainstem is essential for cardiac and respiratory function, controlling autonomic and homeostatic responses including breathing, central chemosensitivity, heartbeat and blood pressure, all mechanisms that are thought to be involved in SIDS. Connexin-36 (Cx36), the principal component of neuron-to-neuron channels that form the electrical synapses, is present in the specific neural populations of brainstem region involved in the CO2 chemoreception and respiratory control, and its expression is unregulated during this critical period of life. Accordingly, we postulate that Cx36 would be a key element in the pathogenesis of SIDS. To address this issue we have studied how the genetic suppression of Cx36 expression affects to the respiratory pacemaker, central chemoreflexes, cardiorespiratory coupling, and risk for SIDS. Mice lacking Cx36 at postnatal day 14 showed in comparison with control wild-type greater variability in the respiratory rhythmicity, abnormally enhanced ventilatory responses to hypoxia and hypercapnia, more cardiorespiratory phase synchronization and less respiratory sinus arrhythmia. A combination of low O2 and high CO2 content in inspired air was used as exogenous stressor of SIDS; under these conditions all wild-type mice survived while the 40% of Cx36-knockout animals succumbed by respiratory failure

    Emprendimiento social vs innovación social

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    El objetivo de este estudio es realizar una aportación teórica a la literatura existente sobre emprendimiento social e innovación social. En este sentido, la primera de las contribuciones que se plantean en este trabajo es el análisis de las similitudes y diferencias entre estos dos conceptos, intentando generar un cierto consenso en este campo de estudio. Sobre esta base, la segunda de las contribuciones que se plantean en este trabajo es la propuesta de un modelo de creación de valor social centrando en la figura del emprendedor y basado en la innovación como fuerza impulsora del cambio social

    La colaboración internacional en materia de patentes y su efecto sobre la creación de empresas

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    To achieve a high rate of entrepreneurship in a region has become a priority goal for governments and businesses. This paper seeks to shed light on the influence of international patent collaboration (IPC) on entrepreneurial activity at the country level by considering the timing of this relationship. A data panel of 30 countries for the 2005-2017 period is used to go in depth with this relationship. The results show the influence of IPC on the promotion of entrepreneurship in the same year, but especially in the following year.Lograr una alta tasa de emprendimiento en una región se ha convertido en el objetivo prioritario de gobiernos y empresas. Este trabajo arroja luz sobre la influencia de la colaboración internacional en materia de patentes (CIP) en la actividad emprendedora a nivel de país teniendo en cuenta el momento en que se produce esta relación. Con el fin de profundizar en esta relación se utiliza un panel de datos de 30 países para el periodo 2005-2017. Los resultados muestran la influencia de la CIP en la promoción del espíritu empresarial en el mismo año, pero especialmente en el año siguiente
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