1,110 research outputs found

    Ruta de internacionalización para la empresa colombiana: LIDERPUERTAS S.A.S.

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    El trabajo que se presenta obedece al análisis estructurado para la construcción y planteamiento de la ruta de internacionalización de la empresa Líderpuertas SAS a través de la exportación de puertas blindadas, el cual se basa en el estudio de factores fundamentales tanto internos como externos no solo de la empresa si no a su vez del micro y macro entorno durante los últimos 5 años, mediante una ardua investigación exploratoria y metodológica critica, fundamentada en diferentes investigaciones basadas en indicadores que permitan plantear un panorama viable para el crecimiento de la empresa y exportación de sus productos en un escenario internacional altamente cambianteThe work that is presented obeys the structured analysis for the construction and approach of the internationalization route of the company Liderpuertas SAS through the export of armored doors, which is based on the study of fundamental factors both internal and external not only of the company if not in turn of the micro and macro environment during the last 5 years, through arduous exploratory research and critical methodological, based on different investigations based on indicators to be executed, to raise a viable outlook for the growth of the company and export of its products in a highly changing international scene

    Intercalation and confinement of poly(ethylene oxide) in porous carbon nanoparticles with controlled morphologies

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    Polymers confined at the nanometer scale often exhibit a distinct structural and dynamical response compared to their bulk counterparts. In this study, we observe that the confinement of poly(ethylene oxide) (PEO) in the nanopores of carbon nanoparticles (CNPs) leads to the suppression of crystallization and to a significant reduction of the Cp at the glass transition. We ask whether these changes are dominated by interfacial interactions (van der Waals type) or by geometrical constraints. For pore diameters below 2 nm (micropores following IUPAC nomenclature), we find that the larger the pore surface, the higher the amount of PEO intercalated in the micropores and, consequently, the larger the reduction of the Cp at the glass transition (up to 50%). For pore diameters in the range 2-50 nm (mesopores), larger pore surfaces lead to a higher amount of PEO adsorbed on the mesopore walls and the smaller the reduction of the Cp at the glass transition. Under these conditions of spatial confinement at the nanoscale, PEO chains cannot arrange themselves into large crystalline domains, as evidenced by a negligible degree of crystallization of at most 1.8%. High-resolution inelastic neutron scattering data show that the PEO chains confined in the pores of CNP adopt a planar zigzag conformation, which is distinctly different from those characteristic of the 7/2 helical structure of the bulk crystal.The authors gratefully acknowledge the support of the Spanish MEC (MAT2012-39199-C02-02 and MAT2012-31088), the Basque Government (IT-654-13), and the UK Science and Technology Facilities Council for the provision of beam time on the TOSCA spectrometer. P.P. acknowledges a PhD research contract from UCM (BE45/10). F.F.A. and S.R. acknowledge financial support from the UK Science and Technology Facilities Council.Peer Reviewe

    Flora y vegetación de la marisma de Doñana en el marco del proyecto de restauración ecológica Doñana 2005

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    Doñana 2005 is an ambitious ecological restoration project that is developed in the wetlands of the Doñana protected space (SW Spain). The objective of this article is to present the preliminary results of the Flora and Vegetation Team linked to the project. Floristic spectrum and phytogeographical elements from the flora of the study area are shown. Furthermore, data corresponding to the evolution of the land cover vegetation of the studied zones is offered.Doñana 2005 es un ambicioso proyecto de restauración ecológica que se desarrolla en el los humedales del espacio protegido de Doñana (SW España). El objetivo de este artículo es dar a conocer los resultados preliminares del Equipo de Flora y Vegetación vinculado a dicho proyecto. Se muestran el espectro florístico y los elementos fitogeográficos de la flora del área de estudio. Asimismo se ofrecen datos correspondientes a la evolución de la cubierta vegetal de las zonas estudiadas

    Tuning melatonin receptor subtype selectivity in oxadiazolone-based analogues: Discovery of QR2 ligands and NRF2 activators with neurogenic properties

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    New multi-target indole and naphthalene derivatives containing the oxadiazolone scaffold as a bioisostere of the melatonin acetamido group have been developed. The novel compounds were characterized at melatonin receptors MT1R and MT2R, quinone reductase 2 (QR2), lipoxygenase-5 (LOX-5), and monoamine oxidases (MAO-A and MAO-B), and also as radical scavengers. We found that selectivity within the oxadiazolone series can be modulated by modifying the side chain functionality and coplanarity with the indole or naphthalene ring. In phenotypic assays, several oxadiazolone-based derivatives induced signalling mediated by the transcription factor NRF2 and promoted the maturation of neural stem-cells into a neuronal phenotype. Activation of NRF2 could be due to the binding of indole derivatives to KEAP1, as deduced from surface plasmon resonance (SPR) experiments. Molecular modelling studies using the crystal structures of QR2 and the KEAP1 Kelch-domain, as well as the recently described X-ray free-electron laser (XFEL) structures of chimeric MT1R and MT2R, provided a rationale for the experimental data and afforded valuable insights for future drug design endeavoursThe authors gratefully acknowledge the following financial supports: Spanish Ministry of Science, Innovation and Universities; Spanish Research Agency; and European Regional Development Funds (grants RTI2018-093955-B-C21 and SAF2015-64948-C2-1-R to M.I.R.-F.; RTI2018-095793-B-I00 to M.G.L., SAF2015-64629-C2- 2-R to F.G.), General Council for Research and Innovation of the Community of Madrid and European Structural Funds (grant B2017/BMD-3827 e NRF24ADCM), Health Institute Carlos III (Miguel Servet II ProgramCP16/00014 and grant PI17/01700 to R.L.). CH-A and P.M. thank their PhD fellowships from Spanish Ministry of Education (MEC, PhD grant FPU16/01704 and mobility grant FPUEST17/00233 to CH-A and FPU13/03737 to P.M.)

    Risk Factors for Amoxicillin-Clavulanate Resistance in Community-Onset Urinary Tract Infections Caused by Escherichia coli or Klebsiella pneumoniae : The Role of Prior Exposure to Fluoroquinolones

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    Background: High rates of amoxicillin-clavulanate (AMC) resistance among Enterobacterales isolated from urinary tract infections (UTIs) were observed in our area. The aim of this study was to identify risk factors associated with AMC resistance in patients with community-onset UTI in emergency departments (EDs). Methods: A retrospective study was performed of all ED patients with positive urine cultures for Escherichia coli or Klebsiella pneumoniae in a Spanish tertiary-care hospital. Results: 330 urine cultures in all were included: 261 (79.1%) for E. coli and 69 (20.90%) for K. pneumonia. Rates of AMC resistance were 14.94% and 34.78%, respectively. UTI was clinically confirmed in 212 (64.24%) cases. Previous antimicrobial exposure was independently associated with AMC resistance development in E. coli and K. pneumoniae urinary isolates (OR = 2.94, 95% CI = 1.55-5.58). Analyses of infected patients revealed that previous exposure to fluoroquinolones (OR = 3.33, 95% CI = 1.10-10.12, p = 0.034) and to AMC (OR = 5.68, 95% CI = 1.97-16.44, p = 0.001) was significantly associated with isolation of AMC-resistant strains. Conclusions: Prior antibiotic exposure, particularly to AMC or fluoroquinolones, was the only independent risk factor associated with development of AMC resistance in E. coli and K. pneumoniae urinary isolates from patients attending the ED

    Caldera Andamarca

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    En el área adyacente a la ciudad de Andamarca, hoja de Querobamba, departamento de Ayacucho, existe una gran depresión morfológica, constituida esencialmente por rocas volcánicas del Neógeno- Cuaternario. Destaca una morfología suave que corresponde a tobas e Ignimbritas de la Formación Andamarca, que rodea a estrato volcanes más altos, semidestruidos con drenaje radial centrífugo, conformados por lavas, piroclastos y depósitos epiclásticos asignados al Grupo Barroso

    Caracterización biológica en la zona de transición bosque-páramo del Complejo de Páramos Chingaza, Colombia

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    The Chingaza paramo complex is located in the Colombian eastern Cordillera, in the departments of Cundinamarca, Boyacá and Meta. Most of our current knowledge about this complex comes from studies conducted near Bogotá and some focal sectors in the National Natural Park Chingaza. The goal of this study was to characterize the treeline transition zone through five elevational transects. As a result, we report 11,588 occurrences and 1382 data of functional traits for plants, edaphic fauna, amphibians, reptiles, and birds. In addition, we report occurrences from two vulnerable (VU) plant species (Hedyosmum parvifolium and Centronia brachycera) and a new endemic species (Puya loca). Preliminary analyses show natural variation in the landscape, community composition and altitudinal location of transition zones along the gradient and between locations. Using this dataset, it is possible to recognize defined transitions between high Andean forests and paramo ecosystems, and their elevation turnover through their physiognomic, floristic, ecological and chorological attributes.La mayor parte de los estudios realizados hasta el momento sobre el complejo de páramos de Chingaza se han desarrollado principalmente en las zonas cercanas a Bogotá y algunos sectores del Parque Nacional Natural Chingaza. El objetivo del presente estudio fue caracterizar la zona de transición bosque-páramo en el complejo. Realizamos 5 transectos altitudinales en áreas con buen estado de conservación, en los que se obtuvieron 11,588 registros de ocurrencias y 1382 registros de rasgos funcionales de vegetación, edafofauna, anfibios y aves. Registramos dos especies de plantas en estado vulnerable (VU) (Hedyosmum parvifolium y Centronia brachycera) y un nuevo taxón endémico para este complejo de páramo (Puya loca). Análisis preliminares de los datos presentados sugieren variación en estructura biótica a lo largo del gradiente, y cambios en la composición de las comunidades. Con la información presentada se logró identificar la zona de transición entre el bosque altoandino y el páramo por medio de diversos atributos fisonómicos, florísticos, ecológicos y corológicos

    ENE-COVID nationwide serosurvey served to characterize asymptomatic infections and to develop a symptom-based risk score to predict COVID-19

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    Objectives: To characterize asymptomatic SARS-CoV-2 infections and develop a symptom-based risk score useful in primary healthcare. Study design and setting: Sixty-one thousand ninty-two community-dwelling participants in a nationwide population-based serosurvey completed a questionnaire on COVID-19 symptoms and received an immunoassay for SARS-CoV-2 IgG antibodies between April 27 and June 22, 2020. Standardized prevalence ratios for asymptomatic infection were estimated across participant characteristics. We constructed a symptom-based risk score and evaluated its ability to predict SARS-CoV-2 infection. Results: Of all, 28.7% of infections were asymptomatic (95% CI 26.1-31.4%). Standardized asymptomatic prevalence ratios were 1.19 (1.02-1.40) for men vs. women, 1.82 (1.33-2.50) and 1.45 (0.96-2.18) for individuals <20 and ≥80 years vs. those aged 40-59, 1.27 (1.03-1.55) for smokers vs. nonsmokers, and 1.91 (1.59-2.29) for individuals without vs. with case contact. In symptomatic population, a symptom-based score (weights: severe tiredness = 1; absence of sore throat = 1; fever = 2; anosmia/ageusia = 5) reached standardized seroprevalence ratio of 8.71 (7.37-10.3), discrimination index of 0.79 (0.77-0.81), and sensitivity and specificity of 71.4% (68.1-74.4%) and 74.2% (73.1-75.2%) for a score ≥3. Conclusion: The presence of anosmia/ageusia, fever with severe tiredness, or fever without sore throat should serve to suspect COVID-19 in areas with active viral circulation. The proportion of asymptomatics in children and adolescents challenges infection control.The ENE-COVID study was supported by the Spanish Ministry of Health, the Institute of Health Carlos III, and the Spanish National Health System. The funders were in- volved in the study logistics, but they had no role in study design or in the collection, analysis, interpretation of data, or the decision to submit the article for publicationS

    Novel potential predictive markers of sunitinib outcomes in long-term responders versus primary refractory patients with metastatic clear-cell renal cell carcinoma

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    Background: several potential predictive markers of efficacy of targeted agents in patients with metastatic renal cell carcinoma (mRCC) have been identified. Interindividual heterogeneity warrants further investigation. Patients and methods: multicenter, observational, retrospective study in patients with clear-cell mRCC treated with sunitinib. Patients were classified in two groups: long-term responders (LR) (progression-free survival (PFS)≥22 months and at least stable disease), and primary refractory (PR) (progressive disease within 3-months of sunitinib onset). Objectives were to compare baseline clinical factors in both populations and to correlate tumor expression of selected signaling pathways components with sunitinib PFS. Results: 123 patients were analyzed (97 LR, 26 PR). In the LR cohort, overall response rate was 79% and median duration of best response was 30 months. Median PFS and overall survival were 43.2 (95% confidence intervals[CI]:37.2-49.3) and 63.5 months (95%CI:55.1-71.9), respectively. At baseline PR patients had a significantly lower proportion of nephrectomies, higher lactate dehydrogenase and platelets levels, lower hemoglobin, shorter time to and higher presence of metastases, and increased Fuhrman grade. Higher levels of HEYL, HEY and HES1 were observed in LR, although only HEYL discriminated populations significantly (AUC[ROC]=0.704; cut-off=34.85). Increased levels of hsa-miR-27b, hsa-miR-23b and hsa-miR-628-5p were also associated with prolonged survival. No statistical significant associations between hsa-miR-23b or hsa-miR-27b and the expression of c-Met were found. Conclusions: certain mRCC patients treated with sunitinib achieve extremely long-term responses. Favorable baseline hematology values and longer time to metastasis may predict longer PFS. HEYL, hsa-miR-27b, hsa-miR-23b and hsa-miR-628-5p could be potentially used as biomarkers of sunitinib response

    Novel potential predictive markers of sunitinib outcomes in long-term responders versus primary refractory patients with metastatic clear-cell renal cell carcinoma

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    Background: Several potential predictive markers of efficacy of targeted agents in patients with metastatic renal cell carcinoma (mRCC) have been identified. Interindividual heterogeneity warrants further investigation. Patients and methods: Multicenter, observational, retrospective study in patients with clear-cell mRCC treated with sunitinib. Patients were classified in two groups: long-term responders (LR) (progression-free survival (PFS)=22 months and at least stable disease), and primary refractory (PR) (progressive disease within 3-months of sunitinib onset). Objectives were to compare baseline clinical factors in both populations and to correlate tumor expression of selected signaling pathways components with sunitinib PFS. Results: 123 patients were analyzed (97 LR, 26 PR). In the LR cohort, overall response rate was 79% and median duration of best response was 30 months. Median PFS and overall survival were 43.2 (95% confidence intervals[CI]:37.2-49.3) and 63.5 months (95%CI:55.1-71.9), respectively. At baseline PR patients had a significantly lower proportion of nephrectomies, higher lactate dehydrogenase and platelets levels, lower hemoglobin, shorter time to and higher presence of metastases, and increased Fuhrman grade. Higher levels of HEYL, HEY and HES1 were observed in LR, although only HEYL discriminated populations significantly (AUC[ROC]=0.704; cut-off=34.85). Increased levels of hsa-miR-27b, hsa-miR-23b and hsa-miR-628-5p were also associated with prolonged survival. No statistical significant associations between hsa-miR-23b or hsa-miR-27b and the expression of c-Met were found. Conclusions: Certain mRCC patients treated with sunitinib achieve extremely long-term responses. Favorable baseline hematology values and longer time to metastasis may predict longer PFS. HEYL, hsa-miR-27b, hsa-miR-23b and hsa-miR- 628-5p could be potentially used as biomarkers of sunitinib response
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