444 research outputs found

    Understanding the relevance of national culture in international business research: a quantitative analysis

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    This review is a comprehensive quantitative analysis of the International Business literature whose focus is on national culture. The analysis relies on a broad range of bibliometric techniques as productivity rankings, citation analysis (individual and cumulative), study of collaborative research patterns, and analysis of the knowledge base. It provides insights on (I) faculty and institutional research productivity and performance; (II) articles, institutions, and scholars’ influence in the contents of the field and its research agenda; and (III) national and international collaborative research trends. The study also explores the body of literature that has exerted the greatest impact on the researched set of selected articles.info:eu-repo/semantics/publishedVersio

    Benchmarking of meteorological indices for sky cloudiness classification

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    Sky classification is a complex problem, due in part to such abstract conceptual definitions as clear, intermediate, and overcast, as well as other intermediate ranges. The CIE (Commission Internationale de L’Éclairage) Standard classification offers a solution to this problem, although its application requires data on the luminance distribution of the whole sky that are less commonly available. A benchmarking and classification system of ten meteorological indices is introduced in this study to classify the sky types from overcast to clear. The indices can be calculated from measurements of global, diffuse, and direct irradiance that are widely available from meteorological ground stations. The classification system uses confusion matrices, a machine-learning tool that generates a visual display of the results of supervised-learning algorithms. The CIE Standard skies classification, applied to half hourly sky-scanner measurements in Burgos (Spain), over the period June 2016 - May 2017, is used in this study as a baseline reference for a comparative review of the results from the meteorological indices and their results. They are classified by four performance ratings: Accuracy, Jaccard, Cohen, and Matthews, which feature both classification similarity and the randomness of any agreement. All meteorological indices yielded a high average degree of accuracy - close to 80% - in a detailed review of their classification. Neverthless, the results suggested that Perez’s Clearness Index based on global, diffuse and direct radiation measurements offered the most precise classification of the skies, followed closely by the Klucher Clearness Index and the Perraudeau Nebulosity Index.Regional Government of Castilla y León under the “Support Program for Recognized Research Groups of Public Universities of Castilla y León” (ORDEN EDU/667/2019) and the Spanish Ministry of Science, Innovation & Universities under the I + D + i state programme “Challenges Research Projects” (Ref. RTI2018-098900-B-I00

    Seasonal caracterization of CIE standard sky types above Burgos, northwestern Spain

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    Outdoor daylight conditions in Burgos, Spain, are studied throughout a full year. The CIE standard sky type is selected in accordance with the lowest RMSD (Root Mean Square Deviation) following the comparison of both the theoretical and the experimental luminance distributions in the sky hemisphere. The original criterion to determine the type of sky, the SSLD (the Standard Sky Luminance Distribution), is difficult to apply in certain places and at times when the solar elevation is higher than 35°. In consequence, two alternative procedures are used and compared in this study: the Tregenza method and the Normalization Rate (NR) introduced by Littlefair. The selection was taken from luminance distribution data of 145 patches of the sky hemisphere recorded between June 2016 and May 2017. The most frequent sky type observed in Burgos was V.5. (cloudless polluted with a broad solar corona), with a frequency of occurrence close to 20%. Notwithstanding that observation, the group of clear skies exhibited a higher frequency (in almost 50% of the cases under study, using both methods). The skies above Burgos were of an overcast sky type in less than 25% of cases, a situation with a higher likelihood in winter and in autumn, while in spring and summer the skies tended to be clear and cloud free. Both of the methodologies showed similar results in percentage terms and in confusion matrixes with almost insignificant differences when compared on a monthly, a seasonal, and an annual basis. Nevertheless, some mismatches were located in the highest solar elevation values.Regional Government of Castilla y León (Ref. BU034U16), under European Regional Development Fund, and the Spanish Ministry of Economy, Industry and Competitiveness, under the I+D+i State Programme Challenges for the Society (Ref. ENE-2014-54601-R

    Estudio de la obesidad y del sobrepeso como factores de riesgo de la prevalencia y severidad del asma en niños de Valencia

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    [email protected]; [email protected]; [email protected]: La obesidad y el sobrepeso se han descrito como factores de riesgo asociados a la prevalencia y severidad del asma en niños y adolescentes. El objetivo del estudio ha sido el valorar el papel de la obesidad en el asma infantil. Ámbito de estudio y sujetos:Estudio realizado en niños y adolescentes entre 8 y 15 años, elegidos por un muestreo aleatorio tipo cluster entre los niños que estudiaban en 80 colegios, el cual representa el 30% de los colegios de la ciudad de Valencia. Material y métodos:El análisis de los datos se organizó en dos grupos, obesos (aquellos niños en un percentil superior al 85 del Índice de Masa Corporal (kg/m2), tomando como referencia la población española) y no obesos, cuando no cumplian esta condición. Se calcularon la prevalencia de los diferentes parámetros con un intervalo de confianza al 95%, y el riesgo relativo (RR) de los síntomas compatibles con asma entre niños obesos comparándolos con los no obesos. Resultados: No se obtuvo un riesgo relativo significativo para la obesidad con respecto al asma en aquellos niños por encima del percentil 85. Por otra parte, un incremento en el riesgo en relación con la severidad del asma se observó con la obesidad, principalmente en el percentil 85 (RR = 1,51 de sufrir entre 4-12 ataques de pitos y RR = 1,86 de sufrir más de 12 ataques en niños obesos frente a los no obesos) Conclusiónes: En este estudio, no identificamos un riesgo más alto de asma entre niños obesos frente a los no obesos, aunque encontramos que hubiera un riesgo más alto de severidad de síntomas asmáticos. En relación con la severidad del asma, observamos un riesgo más alto de ataques de pitos y sibilancias entre los niños obesos en los percentiles 85 y 95 del Indice de Masa Corporal.Background: Obesity and overweight have been described as factors associated with asthma. Our aim was to evaluate the role obesity plays on asthma in children. Scope and subjects: A study carried out on children and teenagers between 8 and 15 years of age, chosen for a cluster-type random sampling from children who studied in 80 schools, which represents 30% of the schools in the city of Valencia. Material and Methods: The analysed data was organized into two groups, obese (from the Body Mass Index (Kg/m2)), showing children with a percentile over 85% of the measuring reference for the Spanish population) and non obese, when they did not fulfil this condition. The prevalence of the different parameters studied was calculated by an Interval of Confidence of 95%. The risk was calculated (Relative Risk) from those symptoms compatible with asthma among obese children compared to non obese children. Results: No significant relative risk (RR) was seen for obesity with regards to asthma in those percentiles of obesity over 85. Otherwise, an increase in the relative risk (RR) regarding the severity of asthma was seen in relation to obesity, mainly in the 85th percentile (RR = 1.51 of suffering between 4-12 wheezing attacks and RR = 1.86 of suffering more than 12 attacks in obese children as opposed to non obese children). Conclusions: In this study, we did not identify a higher risk of asthma among obese children than among non obese children, although we did find there was a higher risk of severity of asthmatic symptoms. As far as the severity of the asthma is concerned, we saw a higher risk of wheezing and whistling attacks among obese children with the 85th and the 95th percentiles according to the Body Mass [email protected]; [email protected]; [email protected]

    Evaluation of the vertical sky component without obstructions for daylighting in Burgos, Spain

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    Daylight availability knowledge is the first step for an energetic and visually e cient building and city design. It can be estimated with the Vertical Sky Component (VSC), which is defined as the ratio of the vertical di use illuminance over the unobstructed horizontal di use illuminance, simultaneously measured at the same point. These illuminance magnitudes are obtained from luxmeter measurements but these data are scarce. Alternatively, VSC can be obtained from prior knowledge of the sky illuminance distribution, which can be measured with a sky scanner device or by reference to the CIE (Commission Internationale de L’Éclairage) Standard classification for homogeneous skies. Both approaches are compared in this study. The coherence of the results obtained for the four cardinal orientations are analyzed by applying classical statistical parameters and luxmeter measurements as references for the results. The measurement campaign was completed between September 2016 and January 2019 in Burgos (Spain), as representative case study and specific contribution of this work. It was observed that the VSC values were higher than 100 in many cases: 21.94% for the south- and 33.6% for the east-facing vertical surfaces. The study highlights the good daylighting conditions in Burgos, mainly due to the predominance of clear skies over much of the year. This fact implies high daylight availability that, with e cient city planning and building design, could potentially lead reduction energy consumption of buildings, improvements in visual comfort, and the well-being of occupants.Regional Government of Castilla y León under the “Support Program for Recognized Research Groups of Public Universities of Castilla y León” (ORDEN EDU/667/2019) and the Spanish Ministry of Science, Innovation & Universities under the I+D+i state program “Challenges Research Projects” (Ref. RTI2018-098900-B-I00). Diego Granados López also thankfully acknowledges the economic support from the Junta de Castilla-León (ORDEN EDU/556/2019

    Salivary DNA Methylation as an Epigenetic Biomarker for Head and Neck Cancer. Part I: A Diagnostic Accuracy Meta-Analysis

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    DNA hypermethylation is an important epigenetic mechanism for gene expression inactivation in head and neck cancer (HNC). Saliva has emerged as a novel liquid biopsy representing a potential source of biomarkers. We performed a comprehensive meta-analysis to evaluate the overall diagnostic accuracy of salivary DNA methylation for detecting HNC. PubMed EMBASE, Web of Science, LILACS, and the Cochrane Library were searched. Study quality was assessed by the Quality Assessment for Studies of Diagnostic Accuracy-2, and sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (dOR), and their corresponding 95% confidence intervals (CIs) were calculated using a bivariate random-effect meta-analysis model. Meta-regression and subgroup analyses were performed to assess heterogeneity. Eighty-four study units from 18 articles with 8368 subjects were included. The pooled sensitivity and specificity of salivary DNA methylation were 0.39 and 0.87, respectively, while PLR and NLR were 3.68 and 0.63, respectively. The overall area under the curve (AUC) was 0.81 and the dOR was 8.34. The combination of methylated genes showed higher diagnostic accuracy (AUC, 0.92 and dOR, 36.97) than individual gene analysis (AUC, 0.77 and dOR, 6.02). These findings provide evidence regarding the potential clinical application of salivary DNA methylation for HNC diagnosisThis work was co-funded by the Instituto de Salud Carlos III (ISCIII) (PI20/01449) and the European Regional Development Fund (FEDER). A.D.-L. is funded by a “Juan Rodés” contract from ISCIII (JR17/00016). L.M.-R. is funded by a “Miguel Servet” contract from ISCIII (CP20/00129)S

    Rapid and simultaneous determination of histidine metabolism intermediates in human and mouse microbiota and biomatrices

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    Histidine metabolism is a key pathway physiologically involved in satiety, recognition memory, skin, and neural protection and allergic diseases. Microbiologically-produced imidazole propionate induces type II diabetes and interferes with glucose lowering drugs. Despite their determinant health implications, no single method simultaneously assesses histidine metabolites in urine, feces, and microbiota. The aim of this study was to develop a simple, rapid, and sensitive method for the determination of histidine and its major bioactive metabolites histamine, N-acetylhistamine, imidazole-4-acetate, cis-urocanate, trans-urocanate, glutamate and imidazole propionate, using ultrahigh-performance liquid chromatography with electrospray ionization tandem mass spectrometry. An innovative simple extraction method from small aliquots of human and mice urine, feces and microbial cell extracts was coupled to separation in a 6.5 min chromatographic run. The successful performance allowed accurate and precise quantification of all metabolites in mouse feces, suggesting broad exchange of histidine metabolites between the gut and mice. Higher urine histamine, histamine to histidine ratio, and imidazole-4-acetate pointed to an underlying inflammatory or allergic process in mice compared to human subjects. N-acetylhistamine and imidazole propionate were detected in human and mouse feces, confirming its origin from gut microbial metabolism. Our novel and robust analytical method captured histidine metabolism in a single assay that will facilitate broad and deep histidine metabolic phenotyping assessing the impact of microbiota on host health in large-scale human observational and interventional studies.The authors are grateful to the Spanish Ministry of Education, Culture and Sports for the pre-doctoral fellowship granted to Inmaculada Acuña (FPU16/04587). Inmaculada Acuña participated in the PhD Program in Nutrition and Food Science of the University of Granada. The results of this manuscript are part of Inmaculada Acuña PhD thesis. This work was carried out within the frame of GP/EFSA/ENCO/380 2018/03/G04: OBEMIRISK: Knowledge platform for assessing the risk of Bisphenols on gut microbiota and its role in obesogenic phenotype: looking for biomarkers. This research was also funded by FEDER-Infrastructure-Consejería de Economía, Conocimiento, Empresas y Universidad: IE_2019-198.S

    Cooperación e internacionalización: el caso de ALSA

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    By focusing on the case of Alsa, this paper analyzes the role of cooperative agreements in internationalization processes on the part of service companies. Alsa, which is now part of the British National Express, has been the Spanish road passenger transport industry’s leader for years and has achieved extensiveinternational growth. Over five decades, cooperation has played a key role in its international growth, mainly due to institutional and cultural factors. Alsa has developed a wide range of horizontal strategic alliances with local partners in host countries: from network exchange to joint ventures, including shared acquisition processes.El presente trabajo analiza el papel que los acuerdos de cooperación desempeñan en la internacionalización de las empresas de servicios a través del estudio de un caso, el de la empresa Alsa. Actualmente integrada en el gigante National Express, Alsa ha liderado el sector del transporte colectivo de viajeros por carretera en nuestro país durante décadas, al tiempo que ha desarrollado una extensa presencia internacional. La cooperación ha constituido una constante en los casi cincuenta años de crecimiento exterior de la compañía, consecuencia, principalmente, de factores institucionales y culturales que han hecho necesaria la participación en sus proyectos de socios locales con los que ha abordado un amplio abanico de fórmulas colaborativas: desde la participación en alianzas horizontales dirigida a facilitar el intercambio de redes de atención al cliente, a la constitución de empresas mixtas con socios procedentes del mercado receptor o la realización de procesos de adquisición compartida
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