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La cordillera de los Andes es la cadena montañosa más larga del mundo, influye directamente en el territorio en aspectos como el clima, las comunicaciones o las relaciones sociales, y ha sido representada en múltiples ocasiones en producciones audiovisuales. En el artículo se indaga el papel que tiene la geografía en el desarrollo de las narraciones cinematográficas que tienen como marco la cordillera de los Andes, al dar a conocer imaginarios geográficos que se proyectan a través del cine. La investigación es de naturaleza analítico-descriptiva, con una metodología cuantitativa y la utilización de la técnica de la observación científica. Se seleccionaron un total de veintiún filmaciones en las que los Andes son protagonistas, y se analizaron los fenómenos geográficos existentes en este espacio geográfico. Los resultados muestran la existencia de numerosos rodajes en los que la trama se desarrolla en los Andes y el espectador puede contemplar fenómenos geográficos tanto físicos (el cambio climático o los conflictos ambientales) como humanos (las actividades económicas o el urbanismo). La relevancia de este estudio recae en que hasta la fecha no se ha realizado ninguna pesquisa acerca de la geografía de la cordillera vista a través del cine. Asimismo, este trabajo puede abrir nuevas investigaciones semejantes para otros espacios geográficos.

La verticalidad es el fundamento de la gran variedad de ecorregiones que hacen de los Andes uno de los espacios más heterogéneos del planeta, con diferentes climas y comunidades vegetales. Sobre estas montañas se han construido diferentes paisajes agrarios, compuestos por mosaicos de campos de cultivo, terrazas, obras de riego y asentamientos de población. Hoy en día constituyen un modelo único de agricultura sostenible y resiliente a los cambios climáticos. El valor excepcional de estos paisajes ha sido reconocido por la ONU al designarlos como Sistemas Importantes del Patrimonio Agrícola Mundial (SIPAM). Mediante diferentes técnicas de análisis e investigación (análisis de datos, documentos, observación directa y entrevistas) se definen estos espacios, se analizan las amenazas que los comprometen y se aquilata la importancia de este modelo de agricultura sostenible frente al cambio climático. Entre los resultados obtenidos se revelan los efectos desiguales que están generando las iniciativas emprendidas a raíz de su declaración como SIPAM o la ausencia de estas.

The Aneto glacier, although it may be considered a very small glacier ( km2), is the largest glacier in the Pyrenees. Its surface and thickness loss have been continuous in recent decades, and there have been signs of accelerated melting in recent years. In this study, thickness and surface losses of the Aneto glacier from 1981 to 2022 are investigated using historical aerial imagery, airborne lidar point clouds and unoccupied aerial vehicle (UAV) imagery. A ground-penetrating radar (GPR) survey conducted in 2020, combined with data from photogrammetric analyses, allowed us to reconstruct the current ice thickness and also the existing ice distribution in 1981 and 2011. Over the last 41 years, the total glacierised area has decreased by 64.7 %, and the ice thickness has decreased, on average, by 30.5 m. The mean remaining ice thickness in autumn 2022 was 11.9 m, as against the mean thickness of 32.9, 19.2 and 15.0 m reconstructed for 1981 and 2011 and observed in 2020, respectively. The results demonstrate the critical situation of the glacier, with an imminent segmentation into two smaller ice bodies and no evidence of an accumulation zone. We also found that the occurrence of an extremely hot and dry year, as observed in the 2021–2022 season, leads to a drastic degradation of the glacier, posing a high risk to the persistence of the Aneto glacier, a situation that could extend to the rest of the Pyrenean glaciers in a relatively short time.

Introducción: La versión cefálica externa (VCE) permite disminuir la tasa de cesáreas por presentación de nalgas, con tasa de éxito variable y sin aumentar las complicaciones obstétricas, aunque se ha descrito que tras VCE exitosa podría haber mayor tasa de cesáreas intraparto así como de partos instrumentales. Objetivo: Analizar resultados y factores relacionados con el parto vaginal tras VCE exitosa comparándolos con el parto en pacientes con feto espontáneamente en cefálica. Método: Estudio retrospectivo de casos y controles en pacientes con VCE realizada en un único centro. Se analizaron variables demográficas y clínicas para determinar resultados maternos, neonatales y predictores de tipo de parto en las pacientes de VCE exitosa. Resultados: Se incluyeron 458 pacientes con VCE, de las cuales 276 (60,3%) fueron exitosas. El éxito se asoció a multiparidad, relajación uterina y sexo fetal femenino. Tuvieron un parto en nuestro centro 227 pacientes. Se emparejaron con 229 controles. El grupo VCE tuvo mayor tasa de cesáreas (23,3 vs. 15,3%; p = 0,03). La distocia fue la indicación más frecuente en ambos grupos. Conclusiones: La VCE es una técnica segura con alta tasa de éxito y buenos resultados. Una vez se consigue una versión exitosa la paciente tiene mayor tasa de cesárea atribuible a cualquier indicación, siendo los demás resultados obstétricos similares a las pacientes con un feto espontáneamente en presentación cefálica.

Accurate knowledge of the seasonal snow distribution is vital in several domains including ecology, water resources management, and tourism. Current spaceborne sensors provide a useful but incomplete description of the snowpack. Many studies suggest that the assimilation of remotely sensed products in physically based snowpack models is a promising path forward to estimate the spatial distribution of snow water equivalent (SWE). However, to date there is no standalone, open-source, community-driven project dedicated to snow data assimilation, which makes it difficult to compare existing algorithms and fragments development efforts. Here we introduce a new data assimilation toolbox, the Multiple Snow Data Assimilation System (MuSA), to help fill this gap. MuSA was developed to fuse remotely sensed information that is available at different timescales with the energy and mass balance Flexible Snow Model (FSM2). MuSA was designed to be user-friendly and scalable. It enables assimilation of different state variables such as the snow depth, SWE, snow surface temperature, binary or fractional snow-covered area, and snow albedo and could be easily upgraded to assimilate other variables such as liquid water content or snow density in the future. MuSA allows the joint assimilation of an arbitrary number of these variables, through the generation of an ensemble of FSM2 simulations. The characteristics of the ensemble (i.e., the number of particles and their prior covariance) may be controlled by the user, and it is generated by perturbing the meteorological forcing of FSM2. The observational variables may be assimilated using different algorithms including particle filters and smoothers as well as ensemble Kalman filters and smoothers along with their iterative variants. We demonstrate the wide capabilities of MuSA through two snow data assimilation experiments. First, 5 m resolution snow depth maps derived from drone surveys are assimilated in a distributed fashion in the Izas catchment (central Pyrenees). Furthermore, we conducted a joint-assimilation experiment, fusing MODIS land surface temperature and fractional snow-covered area with FSM2 in a single-cell experiment. In light of these experiments, we discuss the pros and cons of the assimilation algorithms, including their computational cost.

La innovación desempeña un papel clave en el éxito empresarial, y la política tecnológica resulta fundamental para explicar por qué algunas empresas logran mejores resultados de innovación que otras. Asimismo, el factor humano es indispensable porque son las personas quienes traducen las estrategias y políticas definidas por la dirección en comportamientos de innovación exitosos. Sin embargo, no existe suficiente evidencia sobre la influencia de los sistemas de prácticas y procesos de recursos humanos en la relación entre política tecnológica y resultados de innovación. Esta investigación aborda este vacío, al examinar el papel de la dirección de recursos humanos desde una perspectiva tanto de contenido como de proceso. Se analizaron respuestas de 225 directivos de primer nivel jerárquico de empresas en Colombia en diferentes sectores. Los resultados (pls-sem) muestran un efecto positivo de las políticas de tecnología sobre los sistemas de prácticas de recursos humanos. No se encuentra evidencia que permita soportar un efecto de mediación del sistema de prácticas sobre la relación entre tecnología e innovación. Análisis complementarios permiten identificar un efecto directo de la fortaleza percibida del sistema de recursos humanos sobre los resultados de innovación. Se realizan contribuciones teóricas y prácticas a pesar de la naturaleza transversal del estudio.

Abstract In mountain areas, the phenology and productivity of grassland are closely related to snow dynamics. However, the influence that snow melt timing has on grassland growing still needs further attention for a full understanding, particularly at high spatial resolution. Aiming to reduce this knowledge gap, this work exploits 1 m resolution snow depth and Normalized Difference Vegetation Index observations acquired with an Unmanned Aerial Vehicle at a sub-alpine site in the Pyrenees. During two snow seasons (2019–2020 and 2020–2021), 14 NDVI and 17 snow depth distributions were acquired over 48 ha. Despite the snow dynamics being different in the two seasons, the response of grasslands greening to snow melt-out exhibited a very similar pattern in both. The NDVI temporal evolution in areas with distinct melt-out dates reveals that sectors where the melt-out date occurs in late April or early May (optimum melt-out) reach the maximum vegetation productivity. Zones with an earlier or a later melt-out rarely reach peak NDVI values. The results obtained in this study area, suggest that knowledge about snow depth distribution is not needed to understand NDVI grassland dynamics. The analysis did not reveal a clear link between the spatial variability in snow duration and the diversity and richness of grassland communities within the study area.

Employed for over a century, the traditional way of monitoring sea level variability by tide gauges – in combination with modern observational techniques like satellite altimetry – is an inevitable ingredient in sea level studies over the climate scales and in coastal seas. The development of the instrumentation, remote data acquisition, processing, and archiving in the last decades has allowed the extension of the applications to a variety of users and coastal hazard managers. The Mediterranean and Black seas are examples of such a transition – while having a long tradition of sea level observations with several records spanning over a century, the number of modern tide gauge stations is growing rapidly, with data available both in real time and as a research product at different time resolutions. As no comprehensive survey of the tide gauge networks has been carried out recently in these basins, the aim of this paper is to map the existing coastal sea level monitoring infrastructures and the respective data availability. The survey encompasses a description of major monitoring networks in the Mediterranean and Black seas and their characteristics, including the type of sea level sensors, measuring resolutions, data availability, and existence of ancillary measurements, altogether collecting information about 240 presently operational tide gauge stations. The availability of the Mediterranean and Black seas sea level data in the global and European sea level repositories has been also screened and classified following their sampling interval and level of quality check, pointing to the necessity of harmonization of the data available with different metadata and series in different repositories. Finally, an assessment of the networks' capabilities for their use in different sea level applications has been done, with recommendations that might mitigate the bottlenecks and ensure further development of the networks in a coordinated way, a critical need in the era of human-induced climate changes and sea level rise.

This research analyses the snow depth distribution in canopy gaps across two plots in Central Pyrenees, to improve understanding of snow–forest and topography interactions. Snow depth maps, forest structure–canopy gap (FSCG) characteristics and topographic variables were generated by applying Structure from Motion algorithms (SfM) to images acquired from Unmanned Aerial Vehicles (UAVs). Six flights were conducted under different snowpack conditions in 2021, 2022 and 2023. Firstly, the snow depth database was analysed in terms of the ratio between the radius of the canopy gap and the maximum height of the surrounding trees (r/h), in order to classify the gaps as small‐size, medium‐size, large‐size, or open areas at both sites independently. Then Kendall's correlation coefficients between the snow depth, FSCG and topographic variables were computed and a Random Forest (RF) model for each survey was implemented, to determine the influence of these variables in explaining snow depth patterns. The results demonstrate the consistency of the UAV SfM photogrammetry approach for measuring snowpack dynamics at fine scale in canopy gaps and open areas. At the northeast exposed Site 1, the larger the r/h observed, the greater was the snow depth obtained. This pattern was not evident at the southwest exposed Site 2, which presented high variability related to the survey dates and categories, highlighting the relevance of topography for determining optimum snow accumulation in forested areas. Slope systematically exhibited a negative and significant correlation with snow depth and was consistently the highest‐ranked variable for explaining snow distribution at both sites according to the RF models. Distance to the Canopy Edge also presented high influence, especially at Site 1. The findings suggest differences in the main drivers throughout each site and surveys of the topographic and FSCG variables are needed to understand snow depth distribution over heterogeneous mountain forest domains. [ABSTRACT FROM AUTHOR]

El medio natural y la evolución histórica, junto a diferentes culturas y religiones, han modelado unos conjuntos urbanos únicos y muy diversos en África. Aunque dicho continente continúa siendo el menos urbanizado del mundo, sus ciudades están sometidas a procesos de macrocefalia y se ven impulsadas por un acelerado ritmo de crecimiento. El análisis se centra en un extenso número de películas filmadas que posibilitan abordar un estudio que ofrezca reflexiones teóricas sobre las relaciones entre ficción audiovisual y las áreas urbanas en dicho continente con la finalidad de conocer que espacios se representan, cuáles son sus características y que imaginarios urbanos proyecta la ciudad africana. Desde un punto de vista metodológico se emplea un enfoque amplio, relacionado con la Geografía del Paisaje y la Geografía Cultural y se acota el estudio a las filmaciones de las últimas décadas. Entre los resultados se puede destacar la existencia de nuevas referencias visuales y nuevas claves interpretativas que permiten caracterizar los paisajes urbanos actuales de África.

This research aims at analysing the influence of a holistic configuration of factors related to industry and the characteristics of the entrepreneur and the business, on the survival of social and commercial entrepreneurial initiatives in both, new and consolidated companies. The sample ranges from 2,851 to 2,109 firms, according to the period considered, and has been obtained from the reports of the projects submitted to the Assistance Programme to Young Entrepreneurs, promoted by the Valencian Institute of Youth. Other sources of information have been the Institute’s own reports and the Chambers of Commerce. A configurational analysis is performed using the Fuzzy-Set Qualitative Comparative Analysis. The results obtained show that there is no necessary condition by itself and that there are several sufficient solutions that explain a considerable percentage of survival cases. They also show how the solutions vary significantly and, consequently, the relevance of the different causal antecedents, when the company acquires greater maturity.

A pesar de la creciente importancia que se le ha venido dando al capital humano como objeto de investigación en el ámbito organizacional, en la actualidad sigue habiendo disenso sobre los efectos del uso de configuraciones de prácticas en su gestión sobre los resultados organizativos. Por esto, el presente estudio tiene como objetivo principal analizar los efectos de la adopción de configuraciones de prácticas en la gestión del capital humano sobre los resultados organizativos. Para este fin, se hace una revisión de literatura que posibilita la formulación de hipótesis. Asimismo, se distribuyeron 550 cuestionarios auto administrado a una muestra de 50 empresas nacionales colombianas, multinacionales colombianas, multinacionales norteamericanas y multinacionales españolas, con domicilio todas ellas en Colombia. Los datos se han analizado mediante el análisis por mínimos cuadrados parciales PLS-SEM o PLS path modelling. Los resultados obtenidos sugieren que la utilización de configuraciones de prácticas en la gestión del capital humano no tienen efectos positivos sobre los resultados organizativos. Se concluye que para futuros estudios se deben considerar variables contextuales moderadoras y entender dichas configuraciones de prácticas en el marco global del sistema de gestión humana para cada organización.

The spatial distribution of snow in the mountains is significantly influenced through interactions of topography with wind, precipitation, shortwave and longwave radiation, and avalanches that may relocate the accumulated snow. One of the most crucial model parameters for various applications such as weather forecasts, climate predictions and hydrological modeling is the fraction of the ground surface that is covered by snow, also called fractional snow-covered area (fSCA). While previous subgrid parameterizations for the spatial snow depth distribution and fSCA work well, performances were scale-dependent. Here, we were able to confirm a previously established empirical relationship of peak of winter parameterization for the standard deviation of snow depth σHS by evaluating it with 11 spatial snow depth data sets from 7 different geographic regions and snow climates with resolutions ranging from 0.1 to 3 m. An enhanced performance (mean percentage errors, MPE, decreased by 25 %) across all spatial scales ≥ 200 m was achieved by recalibrating and introducing a scale-dependency in the dominant scaling variables. Scale-dependent MPEs vary between −7 % and 3 % for σHS and between 0 % and 1 % for fSCA. We performed a scale- and region-dependent evaluation of the parameterizations to assess the potential performances with independent data sets. This evaluation revealed that for the majority of the regions, the MPEs mostly lie between ±10 % for σHS and between −1 % and 1.5 % for fSCA. This suggests that the new parameterizations perform similarly well in most geographical regions.