La cuota de mercado como indicador de competitividad en los destinos turísticos: sentido y limitaciones

The market share is the most widely used indicator in the analysis of competitiveness in trade of goods and services. However, their use in tourism is subject to a widespread controversy, especially in those cases where goes together to the territorial analysis. This is because the goals of maximization of this variable by policy-makers, can lead to growth policies that jeopardize the economic and environmental sustainability of a resource-limited destinations. This paper discusses the use, validity and limitations of the market share as an indicator of competitiveness in tourism.La cuota de mercado es el indicador más difundido en el análisis de la competitividad empresarial para todo tipo de bienes y servicios. Sin embargo, su uso en turismo está sometido a una amplia controversia, especialmente cuando el objeto de estudio es la competitividad de los destinos turísticos. Ello es debido a que objetivos de maximización de esta variable en la planificación, pueden conllevar la implementación de políticas de crecimiento comprometedoras de la sostenibilidad económica y ambiental de los citados destinos. Teniendo en cuenta estas consideraciones, en el presente trabajo se discute el uso, validez y limitaciones de la cuota de mercado como indicador de la competitividad de los destinos turísticos

Economic crises and market performance—A machine learning approach

This note analyzes the relationship between economic crises and tourism performance in Spain during the period 1970–2013 using machine learning techniques. Specifically, a regression tree is estimated to confirm that, although the dynamics of Spanish tourism performance is influenced by the general variables established by the literature, the crisis periods disrupt the natural functioning of these dynamics, provoking disturbances that affect the tourism market position of destinations to a greater extent than expected. Conversely, to other econometric techniques, machine learning approach allows us to achieve greater flexibility and enriches the information, estimating the interrelations and thresholds operating in this context

Current Knowledge about the Effect of Nutritional Status, Supplemented Nutrition Diet, and Gut Microbiota on Hepatic Ischemia-Reperfusion and Regeneration in Liver Surgery

Ischemia-reperfusion (I/R) injury is an unresolved problem in liver resection and transplantation. The preexisting nutritional status related to the gut microbial profile might contribute to primary non-function after surgery. Clinical studies evaluating artificial nutrition in liver resection are limited. The optimal nutritional regimen to support regeneration has not yet been exactly defined. However, overnutrition and specific diet factors are crucial for the nonalcoholic or nonalcoholic steatohepatitis liver diseases. Gut-derived microbial products and the activation of innate immunity system and inflammatory response, leading to exacerbation of I/R injury or impaired regeneration after resection. This review summarizes the role of starvation, supplemented nutrition diet, nutritional status, and alterations in microbiota on hepatic I/R and regeneration. We discuss the most updated effects of nutritional interventions, their ability to alter microbiota, some of the controversies, and the suitability of these interventions as potential therapeutic strategies in hepatic resection and transplantation, overall highlighting the relevance of considering the extended criteria liver grafts in the translational liver surgery.This research was supported by the Ministerio de Ciencia, Innovacion y Universidades (RTI2018-095114-B-I00) Madrid, Spain; European Union (Fondos Feder, “una manera de hacer Europa”); CERCA Program/Generalitat de Catalunya and Secretaria d’Universitats I Recerca del Departament d’Economia I Coneixement (2017 SGR-551) Barcelona, Spain

Homogeneity problem for basis expansion of functional data with applications to resistive memories

The homogeneity problem for testing if more than two different samples come from the same population is considered for the case of functional data. The methodological results are motivated by the study of homogeneity of electronic devices fabricated by different materials and active layer thicknesses. In the case of normality distribution of the stochastic processes associated with each sample, this problem is known as Functional ANOVA problem and is reduced to test the equality of the mean group functions (FANOVA). The problem is that the current/voltage curves associated with Resistive Random Access Memories (RRAM) are not generated by a Gaussian process so that a different approach is necessary for testing homogeneity. To solve this problem two different parametric and nonparametric approaches based on basis expansion of the sample curves are proposed. The first consists of testing multivariate homogeneity tests on a vector of basis coefficients of the sample curves. The second is based on dimension reduction by using functional principal component analysis of the sample curves (FPCA) and testing multivariate homogeneity on a vector of principal components scores. Different approximation numerical techniques are employed to adapt the experimental data for the statistical study. An extensive simulation study is developed for analyzing the performance of both approaches in the parametric and non-parametric cases. Finally, the proposed methodologies are applied on three samples of experimental reset curves measured in three different RRAM technologies

Phase-type distributions for studying variability in resistive memories

A new statistical approach has been developed to analyze Resistive Random Access Memory (RRAM) variability. The stochastic nature of the physical processes behind the operation of resistive memories makes variability one of the key issues to solve from the industrial viewpoint of these new devices. The statistical features of variability have been usually studied making use of Weibull distribution. However, this probability distribution does not work correctly for some resistive memories, in particular for those based on the Ni/HfO2/Si structure that has been employed in this work. A completely new approach based on phase-type modeling is proposed in this paper to characterize the randomness of resistive memories operation. An in-depth comparison with experimental results shows that the fitted phase-type distribution works better than the Weibull distribution and also helps to understand the physics of the resistive memories

From Cu(i) and Cu(i)–Cu(ii) mixed-valence clusters to 2D Cu(ii) and Cu(i) coordination polymers supported by a flexible bis-tetrazole organosulfur ligand

Three coordination compounds from the reaction of copper(II) bromide with the flexible bis-tetrazole organosulfur ligand, 1,2-bis(1-methyl-1H-tetrazole-5-ylthio)ethane (bmtte) have been isolated and characterised. The identification of polymeric 2Cu2Br4 (bmtte) (1), trinuclear [Cu3Br4(bmtte)2] (2) and tetra-nuclear [Cu2Br2(bmtte)]2 (3) compounds shows that the reaction conditions have a significant influence on the structure of the complexes formed. Moreover, two polymorphs of the 2D Cu(II )-coordination polymer 1 have been isolated and these crystallise in the monoclinic C2/m (1m) and the triclinic P1¯ (1t) space groups. The thermal stabilities and behaviour in aqueous media of compounds 1–3 were investigated along with the reactivity of compound 2 with CuBr2 and KI. The solid-state reaction between mixed-valence compound 2 with KI or the direct reaction of CuI and bmtte under microwave irradiation allowed the preparation of the polymeric 2 1Cu4 I4 (bmtte)2 (4). The redox behaviour of complexes 2 and 3 was analysed by cyclic voltammetry.Agencia Estatal de Investigación | Ref. PID2019-110218RB-I00Agencia Estatal de Investigación | Ref. PID2020-115004RB-I00Fundación CajaCanarias | Ref. 2021ECO11Xunta de GaliciaUniversidad de La Lagun

Cationic supramolecular hydrogels for overcoming the skin barrier in drug delivery

A cationic bis‐imidazolium‐based amphiphile was used to form thermoreversible nanostructured supramolecular hydrogels incorporating neutral and cationic drugs for the topical treatment of rosacea. The concentration of the gelator and the type and concentration of the drug incorporated were found to be factors that strongly influenced the gelling temperature, gel‐formation period, and overall stability and morphology. The incorporation of brimonidine tartrate resulted in the formation of the most homogeneous material of the three drugs explored, whereas the incorporation of betamethasone resulted in a gel with a completely different morphology comprising linked particles. NMR spectroscopy studies proved that these gels kept the drug not only at the interstitial space but also within the fibers. Due to the design of the gelator, drug release was up to 10 times faster and retention of the drug within the skin was up to 20 times more effective than that observed for commercial products. Experiments in vivo demonstrated the rapid efficacy of these gels in reducing erythema, especially in the case of the gel with brimonidine. The lack of coulombic attraction between the gelator-host and the guest-drug seemed particularly important in highly effective release, and the intermolecular interactions operating between them were found to lie at the root of the excellent properties of the materials for topical delivery and treatment of rosacea

El capital humano como factor estratégico para la competitividad del sector turístico

Los importantes cambios acaecidos en los últimos años, han modificado el panorama del mercado turístico mundial y le han enfrentado a nuevos retos y oportunidades. Ello ha supuesto la necesidad de estudiar qué nuevos factores y estrategias garantizan la competitividad de las empresas del sector. Entre otros, es sin duda indispensable analizar el papel clave del capital humano turístico como estrategia competitiva en un nuevo contexto internacional. En este trabajo se estudia la importancia creciente del factor humano en los servicios turísticos, como elemento básico y diferenciador, capaz de aportar ventajas competitivas, destacando la importancia del valor de los intangibles en este sector. Asimismo, se analiza el papel clave de la educación y formación turísticas en el desarrollo de estrategias de competitividad en las actividades vinculadas al turismo.The significant changes which have taken place in recent years have modified the panorama of the world tourism market and made it face new challenges and opportunities. This has created the need to study the new factors and strategies which guarantee the competitiveness of firms belonging to this sector. Among other things, it becomes undoubtedly essential to analyse the importance of human capital in tourism as a competitive strategy within a new international context. This paper analyses the growing relevance of the human factor in tourism services as a basic, distinguishing element, able to provide competitive advantages, highlighting the importance of the value of intangibles in this sector. Attention is also paid to the key role that tourism education and training plays in the development of competitiveness strategies in the activities linked to tourism

Effect of A Very Low-Calorie Ketogenic Diet on Food and Alcohol Cravings, Physical and Sexual Activity, Sleep Disturbances, and Quality of Life in Obese Patients

Psychological well-being and hunger and food control are two relevant factors involved in the success of weight-loss therapy in treating obesity. Thus, this study aims to evaluate food and alcohol cravings, physical and sexual activity, sleep, and life quality (QoL) in obese patients following a very low-calorie ketogenic (VLCK) diet, as well as the role of weight lost and ketosis on these parameters. A battery of psychological test was performed in twenty obese patients (12 females, 47.2 +/- 10.2 year and BMI of 35.5 +/- 4.4) through the course of a 4-month VLCK diet on four subsequent visits: baseline, maximum ketosis, reduced ketosis, and endpoint. Each subject acted as their own control. Relevantly, the dietary-induced changes in body composition (7.7 units of BMI lost, 18 kg of fat mass (1.2 kg of visceral fat mass)) were associated with a statistically significant improvement in food craving scores, physical activity, sleepiness, and female sexual function. Overall, these results also translated in a notable enhancement in QoL of the treated obese patients. Therefore, the rapid and sustained weight and fat mass (FM) loss induced by the VLCK diet is associated with good food control and improvements in the psychological well-being parameters in obese subjects, which could contribute to the long-term success of this therapy

Enhancement of Magnetic Hyperthermia by Mixing Synthetic Inorganic and Biomimetic Magnetic Nanoparticles

In this work we report on the synthesis and characterization of magnetic nanoparticles of two distinct origins, one inorganic (MNPs) and the other biomimetic (BMNPs), the latter based on a process of bacterial synthesis. Each of these two kinds of particles has its own advantages when used separately with biomedical purposes. Thus, BMNPs present an isoelectric point below neutrality (around pH 4.4), while MNPs show a zero-zeta potential at pH 7, and appear to be excellent agents for magnetic hyperthermia. This means that the biomimetic particles are better suited to be loaded with drug molecules positively charged at neutral pH (notably, doxorubicin, for instance) and releasing it at the acidic tumor environment. In turn, MNPs may provide their transport capabilities under a magnetic field. In this study it is proposed to use a mixture of both kinds of particles at two different concentrations, trying to get the best from each of them. We study which mixture performs better from different points of view, like stability and magnetic hyperthermia response, while keeping suitable drug transport capabilities. This composite system is proposed as a close to ideal drug vehicle with added enhanced hyperthermia response.We wish to thank FPU2016 grant (Ref. FPU16-04580), RYC-2014-6901 (MINECO, Spain), CGL2016-76723 (MINECO, Spain and FEDER, EU), Unidad Científica de Excelencia UCE-PP2016-05 (UGR) and Plan Propio Beca de iniciación a la investigación para estudiantes de master (UGR)