133 research outputs found

    Tratamiento periodístico de los primeros años de la televisión digital por satélite en España: El País y El Mundo (1996-2003)

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    El objetivo principal de este trabajo es analizar el tratamiento periodístico que realizaron El País y El Mundo sobre la puesta en marcha y evolución de la televisión digital por satélite en España, concretamente desde enero de 1996, año en el que comienzan a configurarse las plataformas digitales, hasta julio de 2003, fecha en la que se inician las emisiones de Digital+, plataforma resultante de la integración de Canal Satélite Digital y Vía Digital. Con la televisión digital por satélite surge en España un nuevo concepto de televisión, tanto en términos de programación como de consumo, una nueva forma de ver y entender este medio de comunicación y entretenimiento, pero sobre todo, se inicia un proceso que más allá del cambio tecnológico que significaba el paso de la televisión convencional o analógica a la digital, tuvo repercusión en lo empresarial y económico, lo político, lo judicial y lo social. Todas estas implicaciones ponían de manifiesto la importancia del momento para la reordenación del sector audiovisual. Por ello, nuestra intención es mostrar qué contaron ambos medios durante el proceso analizado, cómo lo contaron y lo más importante, establecer conclusiones rigurosas sobre por qué lo contaron así. De esta forma podremos afirmar o rechazar la influencia de las estructuras mediáticas y los intereses empresariales en los mensajes periodísticos ya que los diarios elegidos estaban directamente relacionados con cada una de las plataformas: El País, a través del Grupo Prisa y Sogecable en Canal Satélite Digital, y El Mundo en Vía Digital de la que era accionista minoritario. Todo ello mediante un estudio comparativo, fundamentado en el conocimiento científico y cuyas bases epistemológicas de partida son la Economía Política de la Comunicación y el Análisis de Contenido

    The protection of consumer rights in Colombia in the use of electronic commerce e commerce

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    El análisis de la protección de los derechos del consumidor en Colombia en la utilización del comercio electrónico e-commerce, permitió examinar el desarrollo normativo frente a los derechos del consumidor en Colombia en la utilización del comercio electrónico e-commerce; asimismo, escribir los derechos del consumidor en Colombia en la utilización del comercio electrónico e commerce; y, por último determinar la forma de materialización de la protección de los derechos del consumidor en Colombia en la utilización del comercio electrónico e-commerce.The analysis of the protection of consumer rights in Colombia in the use of electronic commerce e-commerce, allowed us to examine the regulatory development against consumer rights in Colombia in the use of electronic commerce e-commerce; also, write the rights of the consumer in Colombia in the use of electronic commerce e-commerce; and, finally, determine the form of materialization of the protection of consumer rights in Colombia in the use of electronic commerce e-commerce

    A Multiple Stakeholder Multicriteria Decision Analysis in Diabetic Macular Edema Management: The MULTIDEX‑EMD Study

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    Background The clinical and economic management of retinal diseases has become more complex following the introduction of new intravitreal treatments. Multicriteria decision analysis (MCDA) offers the potential to overcome the challenges associated with traditional decision-making tools. Objectives A MCDA to determine the most relevant criteria to decision-making in the management of diabetic macular edema (DME) based on the perspectives of multiple stakeholders in Spain was developed. This MCDA was termed the MULTIDEX-EMD study. Methods Nineteen stakeholders (7 physicians, 4 pharmacists, 5 health authorities and health management experts, 1 psychologist, and 2 patient representatives) participated in this three-phase project. In phase A, an advisory board defined all of the criteria that could influence DME treatment decision-making. These criteria were then screened using a discrete choice experiment (DCE) (phase B). Next, a multinomial logit model was fitted by applying the backward elimination algorithm (relevant criteria: p value = 15 letters (p value < 0.001), effect duration per administration (p value = 0.008), retinal detachment (p value < 0.001), endophthalmitis (p value = 0.012), myocardial infarction (p value < 0.001), intravitreal hemorrhage (p value = 0.021), annual treatment cost per patient (p value = 0.001), health-related quality of life (HRQoL) (p value = 0.004), and disability level (p value = 0.021). Conclusions From a multi-stakeholder perspective, the selection of an appropriate treatment for DME patients should guarantee patient safety and maximize the visual acuity improvement and treatment effect duration. It should also contribute to system sustainability by being affordable, it should have a positive impact on HRQoL, and it should prevent disability

    New 3-Dimensional Volumetric Ultrasound Method for Accurate Quantification of Atherosclerotic Plaque Volume.

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    Carotid and femoral plaque burden is a recognized biomarker of cardiovascular disease risk. A new electronic-sweep 3-dimensional (3D)-matrix transducer method can improve the functionality and image quality of vascular ultrasound atherosclerosis imaging. This study aimed to validate this method for plaque volume measurement in early and intermediate-advanced plaques in the carotid and femoral territories. Plaque volumes were measured ex vivo in pig carotid and femoral artery specimens by 3-dimensional vascular ultrasound (3DVUS) using a 3D-matrix (electronic-sweep) transducer and its associated 3D plaque quantification software, and were compared with gold-standard histology. To test the clinical feasibility and accuracy of the 3D-matrix transducer, an experiment was conducted in intermediate-high risk individuals with carotid and femoral atherosclerosis. The results were compared with those obtained using the previously validated mechanical-sweep 3D transducer and established 2-dimensional (2D)-based plaque quantification software. In the ex vivo study, the authors assessed 19 atherosclerotic plaques (plaque volume, 0.76 µL-56.30 μL), finding strong agreement between measurements with the 3D-matrix transducer and the histological gold-standard (intraclass correlation coefficient [ICC]: 0.992; [95% CI: 0.978-0.997]). In the clinical analysis of 20 patients (mean age 74.6 ± 4.45 years; 40% men), the authors found 64 (36 carotid and 28 femoral) of 80 scanned territories with atherosclerosis (measured atherosclerotic volume, 10 μL-859 μL). There was strong agreement between measurements made from electronic-sweep and mechanical-sweep 3DVUS transducers (ICC: 0.997 [95% CI: 0.995-0.998]). Agreement was also high between plaque volumes estimated by the 2D and 3D plaque quantification software applications (ICC: 0.999 [95% CI: 0.998-0.999]). Analysis time was significantly shorter with the 3D plaque quantification software than with the 2D multislice approach with a mean time reduction of 46%. 3DVUS using new matrix transducer technology, together with improved 3D plaque quantification software, simplifies the accurate volume measurement of early (small) and intermediate-advanced plaques located in carotid and femoral arteries.This study was partially funded by grants from the Ministerio de Economia, Industria y Competividad (MEIC) with cofunding from the European Regional Development Fund (ERDF) (SAF2016-75580-R to Dr Bentzon) and (BES-2016-076633 to Dr Nogales). Research funding was also received from the Instituto de Salud Carlos III Spain (PIE16/ 00021 to Drs Bueno and Fuster). The CNIC is supported by the Min- isterio de Ciencia, Innovacion y Universidades (MICINN) and the Pro CNIC Foundation and is a Severo Ochoa Center of Excellence (CEX2020-001041-S). This study forms part of a Master Research Agreement between the CNIC and Philips Healthcare. Drs Sánchez- González, Entrekin, and Collet-Billon are employees of Philips Healthcare. All other authors have reported that they have no re- lationships to disclose related to the contents of this paper.S

    Silk fibroin nanoparticles constitute a vector for controlled release of resveratrol in an experimental model of inflammatory bowel disease in rats.

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    Purpose: We aimed to evaluate the intestinal anti-inflammatory properties of silk fibroin nanoparticles, around 100 nm in size, when loaded with the stilbene compound resveratrol, in an experimental model of rat colitis. Methods: Nanoparticles were loaded with resveratrol by adsorption. The biological effects of the resveratrol-loaded nanoparticles were tested both in vitro, in a cell culture of RAW 264.7 cells (mouse macrophages), and in vivo, in the trinitrobenzenesulfonic acid model of rat colitis, when administered intracolonically. Results: The resveratrol liberation in 1× phosphate-buffered saline (PBS; pH 7.4) was characterized by fast liberation, reaching the solubility limit in 3 hours, which was maintained over a period of 80 hours. The in vitro assays revealed immunomodulatory properties exerted by these resveratrol-loaded nanoparticles since they promoted macrophage activity in basal conditions and inhibited this activity when stimulated with lipopolysaccharide. The in vivo experiments showed that after evaluation of the macroscopic symptoms, inflammatory markers, and intestinal barrier function, the fibroin nanoparticles loaded with resveratrol had a better effect than the single treatments, being similar to that produced by the glucocorticoid dexamethasone. Conclusion: Silk fibroin nanoparticles constitute an attractive strategy for the controlled release of resveratrol, showing immunomodulatory properties and intestinal anti-inflammatory effects

    Tecno retos : una estrategia de formación durante el Covid -19

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    En condiciones normales, en la Tecnoacademia hacemos la formación en nuestras instalaciones. Sin embargo, a causa de la pandemia provocada por el COVID-19, durante el primer semestre del año 2020, generamos una estrategia denominada “retos” con el fin de incentivar a los aprendices a seguir adelante con nuestros cursos. Para esto, cada línea desarrolló tres retos teniendo en cuenta que estuvieran asociados a conceptos teóricos del área y que un aprendiz los pudiera desarrollar con materiales que tuviera a su alcance en casa, los cuales fueran de bajo costo y fácil adquisición. En esta cartilla te presentamos seis módulos con los retos generados por las líneas de formación. En estos, resaltamos los mejores resultados obtenidos por los aprendices inscritos a nuestro programa, donde la creatividad y la innovación son los protagonistas. Por motivos de espacio, solo incluimos tres, pero todas las soluciones presentadas fueron sorprendentes. Por esto, te invitamos a construir tus propias soluciones.Under normal conditions, at the Tecnoacademia we do training at our facilities. However, due to the pandemic caused by COVID-19, during the first semester of 2020, we generated a strategy called “challenges” in order to encourage learners to continue with our courses. For this, each line developed three challenges taking into account that they were associated with theoretical concepts of the area and that an apprentice could develop them with materials that were available at home, which were low cost and easy to acquire. In this booklet we present six modules with the challenges generated by the training lines. In these, we highlight the best results obtained by the apprentices enrolled in our program, where creativity and innovation are the protagonists. For reasons of space, we only included three, but all the solutions presented were surprising. For this reason, we invite you to build your own solutions.Tecnoacademia Regional Valle -- Línea de biotecnología -- Línea de ciencias básicas -- Línea de diseño y prototipado -- Línea de nanotecnología -- Línea de robótica -- Línea de TIC.na106 página

    The effect of cross-linking on the molecular dynamics of the segmental and β Johari–Goldstein processes in polyvinylpyrrolidone-based copolymers

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    The effect of the cross-link density on the molecular dynamics of copolymers composed of vinylpyrrolidone (VP) and butyl acrylate (BA) was studied using differential scanning calorimetry (DSC) and dielectric relaxation spectroscopy (DRS). A single glass transition was detected by DSC measurements. The dielectric spectra exhibit conductive processes and three dipolar relaxations labeled as a, b and g in the decreasing order of temperatures. The cross-linker content affects both a and b processes, but the fastest g process is relatively unaffected. An increase of cross-linking produces a typical effect on the a process dynamics: (i) the glass transition temperature is increased, (ii) the dispersion is broadened, (iii) its strength is decreased and (iv) the relaxation times are increased. However, the b process, which possesses typical features of a pure Johari Goldstein relaxation, unexpectedly loses the intermolecular character for the highest cross-linker content.B.R.F., M.J.S., P.O.S. and M.C. gratefully acknowledge CICYT for grant MAT2012-33483. F.G. and J.M.G. acknowledge the Spanish Ministerio de Economia y Competitividad-FEDER (MAT2014-54137-R) and the Junta de Castilla y Leon (BU232U13).Redondo Foj, MB.; Sanchis Sánchez, MJ.; Ortiz Serna, MP.; Carsí Rosique, M.; García, JM.; García, FC. (2015). The effect of cross-linking on the molecular dynamics of the segmental and β Johari–Goldstein processes in polyvinylpyrrolidone-based copolymers. Soft Matter. 11:7171-7180. https://doi.org/10.1039/c5sm00714cS7171718011V. Bühler , Polyvinylpyrrolidone Excipients for Pharmaceuticals: Povidone, Crospovidone and Copovidone , Springer , Berlin , 2005Haaf, F., Sanner, A., & Straub, F. (1985). Polymers of N-Vinylpyrrolidone: Synthesis, Characterization and Uses. 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    A multiple stakeholder multicriteria decision analysis in diabetic macular edema management: the MULTIDEX‑EMD study

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    Background The clinical and economic management of retinal diseases has become more complex following the introduction of new intravitreal treatments. Multicriteria decision analysis (MCDA) ofers the potential to overcome the challenges associated with traditional decision-making tools. Objectives A MCDA to determine the most relevant criteria to decision-making in the management of diabetic macular edema (DME) based on the perspectives of multiple stakeholders in Spain was developed. This MCDA was termed the MULTIDEX-EMD study. Methods Nineteen stakeholders (7 physicians, 4 pharmacists, 5 health authorities and health management experts, 1 psychologist, and 2 patient representatives) participated in this three-phase project. In phase A, an advisory board defned all of the criteria that could infuence DME treatment decision-making. These criteria were then screened using a discrete choice experiment (DCE) (phase B). Next, a multinomial logit model was ftted by applying the backward elimination algorithm (relevant criteria: p value<0.05). Finally, the results were discussed in a deliberative process (phase C). Results Thirty-one criteria were initially defned (phase A) and grouped into 5 categories: efcacy/efectiveness, safety, organizational and economic impact, patient-reported outcomes, and other therapeutic features. The DCE results (phase B) showed that 10 criteria were relevant to the decision-making process for a 50- to 65-year-old DME patient: mean change in best corrected visual acuity (p value<0.001), percentage of patients with an improvement of ≥15 letters (p value<0.001), efect duration per administration (p value=0.008), retinal detachment (p value<0.001), endophthalmitis (p value=0.012), myocardial infarction (p value<0.001), intravitreal hemorrhage (p value=0.021), annual treatment cost per patient (p value=0.001), health-related quality of life (HRQoL) (p value=0.004), and disability level (p value=0.021). Conclusions From a multi-stakeholder perspective, the selection of an appropriate treatment for DME patients should guarantee patient safety and maximize the visual acuity improvement and treatment efect duration. It should also contribute to system sustainability by being afordable, it should have a positive impact on HRQoL, and it should prevent disability

    Digital photography provides a fast, reliable, and noninvasive method to estimate anthocyanin pigment concentration in reproductive and vegetative plant tissues

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    Anthocyanin pigments have become a model trait for evolutionary ecology as they often provide adaptive benefits for plants. Anthocyanins have been traditionally quantified biochemically or more recently using spectral reflectance. However, both methods require destructive sampling and can be labor intensive and challenging with small samples. Recent advances in digital photography and image processing make it the method of choice for measuring color in the wild. Here, we use digital images as a quick, noninvasive method to estimate relative anthocyanin concentrations in species exhibiting color variation. Using a consumer‐level digital camera and a free image processing toolbox, we extracted RGB values from digital images to generate color indices. We tested petals, stems, pedicels, and calyces of six species, which contain different types of anthocyanin pigments and exhibit different pigmentation patterns. Color indices were assessed by their correlation to biochemically determined anthocyanin concentrations. For comparison, we also calculated color indices from spectral reflectance and tested the correlation with anthocyanin concentration. Indices perform differently depending on the nature of the color variation. For both digital images and spectral reflectance, the most accurate estimates of anthocyanin concentration emerge from anthocyanin content‐chroma ratio, anthocyanin content‐chroma basic, and strength of green indices. Color indices derived from both digital images and spectral reflectance strongly correlate with biochemically determined anthocyanin concentration; however, the estimates from digital images performed better than spectral reflectance in terms of r2 and normalized root‐mean‐square error. This was particularly noticeable in a species with striped petals, but in the case of striped calyces, both methods showed a comparable relationship with anthocyanin concentration. Using digital images brings new opportunities to accurately quantify the anthocyanin concentrations in both floral and vegetative tissues. This method is efficient, completely noninvasive, applicable to both uniform and patterned color, and works with samples of any size
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