A Multi-Temporal Object-Based Image Analysis to Detect Long-Lived Shrub Cover Changes in Drylands

Climate change and human actions condition the spatial distribution and structure of vegetation, especially in drylands. In this context, object-based image analysis (OBIA) has been used to monitor changes in vegetation, but only a few studies have related them to anthropic pressure. In this study, we assessed changes in cover, number, and shape of Ziziphus lotus shrub individuals in a coastal groundwater-dependent ecosystem in SE Spain over a period of 60 years and related them to human actions in the area. In particular, we evaluated how sand mining, groundwater extraction, and the protection of the area affect shrubs. To do this, we developed an object-based methodology that allowed us to create accurate maps (overall accuracy up to 98%) of the vegetation patches and compare the cover changes in the individuals identified in them. These changes in shrub size and shape were related to soil loss, seawater intrusion, and legal protection of the area measured by average minimum distance (AMD) and average random distance (ARD) analysis. It was found that both sand mining and seawater intrusion had a negative effect on individuals; on the contrary, the protection of the area had a positive effect on the size of the individuals’ coverage. Our findings support the use of OBIA as a successful methodology for monitoring scattered vegetation patches in drylands, key to any monitoring program aimed at vegetation preservation

¿Conocía Sherlock Holmes la teoría de grafos?

En este artículo se muestran las ventajas que ofrece la Teoría de Grafos a la hora de resolver determinados problemas clásicos de Matemáticas, que normalmente se suelen intentar probando una a una las diferentes posibilidades existentes, o bien por el conocido método de la “cuenta de la vieja”. Su principal objetivo es mostrar cómo esta Teoría facilita una gran cantidad de estrategias útiles para la resolución de estos problemas, de manera más rápida, elegante y sencilla de la habitual. Uno de estos problemas trata precisamente de cómo Sherlock Holmes pudo resolver un caso de asesinato, utilizando los grafos.In this paper, we show the advantages offered by Graph Theory to solve some classic mathematical problems, which are normally solved by using other non systematic techniques, such that to go one to one testing different possibilities or to use what in Spain is called “la cuenta de la vieja”. Its main goal is to show how Graph Theory allows to systematize and formalize a lot of useful strategies to find the solution of those problems in an easier, smarter and faster way than usual. One of these problems deals with the solution given by Sherlock Holmes to a case of murder by using graphs

Data supporting the forecast of electricity generation capacity from non-conventional renewable energy sources in Colombia

The data included in this study was calculated based on data provided by the national project registry provided by the Colombian government. The data forecasts the evolution of the power generation capacity registered in non-conventional renewable energy source projects in three scenarios of implementation of the power generation capacity registered in the projects. Results can be used to benchmark non-conventional renewable energy sources in Colombia, interpret the effectiveness of renewable policies, and monitor the evolution of non-conventional renewable-based power generation. The data presented in the article relates to the research study: A look to the electricity generation from nonconventional renewable energy sources in Colombia

Perception of risk in construction. Exploring the factors that influence experts in occupational health and safety.

Risk perception is studied in many research disciplines. Although many of the factors that influence the perception of risk in the field of occupational risk prevention are known, there is still no complete understanding of the ways in which professionals in this sector perceive risks. This study analyzes the incidence of sociodemographic variables (gender, age, university degree, seniority of the qualification and professional experience) in the perception of the probability and consequences of accident risk of a group of Construction Safety and Health Experts. Additionally, the incidence of these variables has been evaluated in various stages of a construction. On the basis of a questionnaire survey of 30 construction processes, and applying a linear multilevel regression model, statistically significant differences in perceived risk were obtained depending on the age of the Construction Safety Experts, while it was determined that there is no significant difference in the perception of risk between men and women in this professional sector. Greater discrepancies were found when evaluating the overall risk of construction activities in the early stages of a construction site. Nevertheless, in spite of the sociodemographic differences between Construction Safety Experts, we conclude that their risk assessments are highly coherent

Variación altitudinal y diversidad vegetal en matorrales: Sierra de los Filabres (Almería, España)

The main objetives in this research is to determine vegetational diversity along the transect carried out on the south side of S' de Los Filabres, localiced in southeastern of Iberian Peninsula, from 800 m to the top. Samples were taken at 100 m intervals throughout the transect under study. Further, several climatic and bioclimatic parameters collected at every height station, have been brought into relationshipEl objetivo principal de la investigación ha sido determinar la diversidad vegetal a lo largo del itinerario llevado a cabo en la cara sur de S de Los Filabres situada en el sureste de la Península Ibérica, desde los 800 m de altitud hasta la cima. Las muestras fueron tomadas cada 100 m de desnivel. Además, se han tenido en cuenta magnitudes climáticas y bioclimáticas calculadas para cada estación, en relación con la diversidad registrada. Los aspectos corológicos se consideran también muy importantes para este análisis

A look to the Electricity Generation from Non-Conventional Renewable Energy Sources in Colombia

This study discusses the potentialities and current situation of the electricity generation from non-conventional renewable energy sources (NCRES) in Colombia. In particular, three scenarios considering the increment of NCRES electricity based generation installed capacity are discussed. The three scenarios are compared to the 2020 forecast of the Energy and Mining Planning Unit ((UPME). Overall, it id shown that Colombia has a significant unused NCRES potential, which makes possible to realize the 6% target for NCRE based electricity generation capacity installed by 2020. In particular, the photovoltaic energy is foresee to account for over half of the NCRE mix. Even though the law 1715 is a progress towards integrating NCRE to the National Electric System, more policies and developments are required, to further the NCRE based installed generation capacities

GWAS and meta-analysis identifies 49 genetic variants underlying critical COVID-19

Critical illness in COVID-19 is an extreme and clinically homogeneous disease phenotype that we have previously shown1 to be highly efficient for discovery of genetic associations2. Despite the advanced stage of illness at presentation, we have shown that host genetics in patients who are critically ill with COVID-19 can identify immunomodulatory therapies with strong beneficial effects in this group3. Here we analyse 24,202 cases of COVID-19 with critical illness comprising a combination of microarray genotype and whole-genome sequencing data from cases of critical illness in the international GenOMICC (11,440 cases) study, combined with other studies recruiting hospitalized patients with a strong focus on severe and critical disease: ISARIC4C (676 cases) and the SCOURGE consortium (5,934 cases). To put these results in the context of existing work, we conduct a meta-analysis of the new GenOMICC genome-wide association study (GWAS) results with previously published data. We find 49 genome-wide significant associations, of which 16 have not been reported previously. To investigate the therapeutic implications of these findings, we infer the structural consequences of protein-coding variants, and combine our GWAS results with gene expression data using a monocyte transcriptome-wide association study (TWAS) model, as well as gene and protein expression using Mendelian randomization. We identify potentially druggable targets in multiple systems, including inflammatory signalling ( JAK1), monocyte–macrophage activation and endothelial permeability (PDE4A), immunometabolism (SLC2A5 and AK5), and host factors required for viral entry and replication (TMPRSS2 and RAB2A)

Acerca de tres especies nitrófilas en la provincia de Almería

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MRI visualization of small structures using improved surface coils

In this paper we present the spatial resolution enhancement and noise reduction level achieved with an optimized inductively coupled surface coil specificall designed for our experiments. The technique of designing and implementing customized coils for magnetic resonance imaging of very small structures is described. We have designed a low cost prototype of an inductively coupled circular surface coil, tuned for 1H magnetic resonance imaging at 200 MHz. The coil is mounted on a customized teflo support. The inductive coupling used in this coil improves the signal-to-noise ratio by reducing various loss mechanisms (specially the dielectric losses). Test images have been acquired to determine the evolution of induced articular lesions in a rabbit animal model, as well as brain tumors in rats. The images show high spatial resolution, excellent B1 fiel homogeneity and no ‘‘hot spots’’. Comparing these images with those acquired with conventional coils, one find better spatial resolution and signal-to-noise ratio, as well as larger fiel of view with less intense illumination artifact. The methodology can be used in any application that requires high quality imaging of small structures.Publicad

Optimal design for MRI surface coils

Objetivo: Demostrar la posibilidad de diseñar y construir sondas de superficie o antenas específicas para la visualización de cada tejido en particular; haciendo uso de la técnica IRM, de modo que los resultados obtenidos sean muy superiores a los que se Consiguen mediante una sonda de superficie de propósito general. Material y métodos: El estudio ha sido realizado por el Grupo de Bioingeniería y Telemedicina de la Universidad Politécnica de Madrid y se ha llevado a cabo en el Instiluto Pluridisciplinar en la Universidad Complutense de Madrid, que cuenta con un equipo de resonancia BIOSPEC BMT-47/40 de Bruker: Se han diseñado sondas de superficie construidas a la medida de la región que se desea estudiar; optimizadas de modo que la homogeneidad del campo excitador de la muestra fuera lo más elevada posible, reduciendo además el artefacto de iluminación. Inicialmente se obtuvieron imágenes de un fantoma esférico de 50 mm de diámetro lleno de agua para luego adquirir imágenes de ratas y conejos de laboratorio. Resultados: Las imágenes adquiridas han permitido la comparación de los resultados obtenidos con la sonda comercial proporcionada por el fabricante del equipo y las sondas diseñadas; con estas últimas se consiguen imágenes de mayor calidad, pues además de poder visualizar tejidos más profundos en la muestra disminuye el artefacto de iluminación. Conclusiones: La construcción de sondas de superficie específicas para visualizar un determinado tejido o región anatómica permite mejorar la calidad de las imágenes. La extensión natural de este proyecto actualmente en curso consiste en traspasar estos resultados a equipos destinados a imagen para humanos.Objective: To demonstrate the possibilily of designing and comlmctillg specific slllfaee coils or antellllae for MRI viell'ing of each particular lisslle, producillg beller results Ihall those provided b), a general pll/pose su rface coi l. Material and methods: The slud)' lI'as pe/formed b), the Bioellgilleering alld Telemedicille Group of Madrid Pol)'teehllical Ulliversil)' and Ivas carried out al Ihe Pluridisciplillary IlIslitute of Ihe Ulliversidad Complutellse ill Madrid, usillg a BMT-47/40 BIOSPEC resonance ullit from Bruka SII/face coils Ivere custom-designed al/{I eOllstmctedforeach regioll to be studied, (md optimized to IllOke the specimell excitation field as homogelleous as jJossible, ill additioll lo reducing Ihe brightlless artijact. First, images lI'ere obtailled of a ro//Ild, lI'ater phalllommeasurillg 50 mm ill diamelel; afta lI'hich images of labomtOl)' rals al/{I rabbils lI'ere obtailled. Results: The images thus acqllired lI'ere campa red lI'ith the resulls obtailled Ivilh the coi! provided b), the manufactura of the eqllipment, alld ¡vere foulld to be of beller qualil)', alloll'illg the vielVing of deeper tissue fa the specimell as lI'ell as reducillg the brigllllless arl/facI. Conclusions: The cOllstructioll of sll/face coilsfor viell'illg specific tissues or anatomical regions improves image qualit)'. The lIexl Slep ill this ollgoing ¡J/vjeet lI'ill be the applicatioll of these cOllcepls to II/lits desiglIed for use ill IlIImalls.Publicad