FUNDAMENTOS, PERSPECTIVAS PRESENTES Y FUTURAS DE LA UTILIZACIÓN DE MOLÉCULAS PARA LA CONVERSIÓN DE CALOR EN ELECTRICIDAD

En este trabajo fin de grado se ha realizado una exhaustiva búsqueda bibliográfica sobre materiales termoeléctricos, en particular sobre el empleo de moléculas individuales o ensamblajes de estas en dispositivos a tal efecto.A lo largo del trabajo se exponen los principios básicos de la termoelectricidad, así como los objetivos planteados que hacen que ésta sea objeto de numerosas y diversas investigaciones.Posteriormente se describen algunos de los resultados más relevantes obtenidos con materiales orgánicos e inorgánicos, incluyendo valores experimentales y computacionales que arrojan interesantes conclusiones acerca de la viabilidad de los mismos. También se mencionarán algunos de los materiales nanoestructurados explorados en este campo, con la finalidad de mejorar los resultados obtenidos con los materiales a macro y micro escala. Finalmente centraremos nuestra atención en el uso de moléculas individuales o ensamblajes de estas en forma de monocapas en el campo de la termoelectricidad. Aquí nos detendremos en la metodología que permite analizar las propiedades termoeléctricas de moléculas individuales, así como los parámetros objeto de optimización por parte de los investigadores (conductancia térmica, conductancia eléctrica, coeficiente de Seebeck…) para avanzar hacia la obtención de materiales con las propiedades deseadas.<br /

Primer registro de Digitonthophagus gazella (Fabricius, 1787) y nuevo registro para Euoniticellus intermedius (Reiche, 1849) (Coleoptera: Scarabaeidae Latreille, 1802) en El Salvador

The presence of the beetle Digitonthophagus gazella (Fabricius, 1787) is reported for the first time. In addition, the range of distribution of Euoniticellus intermedius (Reiche, 1849) in El Salvador is expanded, based on information obtained from collections made over twelve years and the current distribution map of E. intermedius in the territory is presented. In addition, the current situation of both species in the country and Central America is briefly discussed.Se reporta por primera vez la presencia del escarabajo Digitonthophagus gazella (Fabricius, 1787). Además, se amplía el rango de distribución de Euoniticellus intermedius (Reiche, 1849) en El Salvador, a partir de información obtenida de colectas realizadas a lo largo de doce años y se presenta el mapa de distribución actual de E. intermedius en el territorio. Adicionalmente, se discute brevemente la situación actual de ambas especies en el país y Centroamérica

Primer reporte de cuatro especies de escarabajos coprófagos (Coleoptera: Scarabaeinae) en El Salvador

We present the first records of four species of Scarabaeinae: Canthidium pseudopuncticolle, Canthon femoralis, Uroxys deavilai and Uroxys microcularis, in El Salvador. We collected the specimens, using feces and carrion baited traps in three zones in the National Park El Imposible in the Southwest of the country. With this report, we contribute to the knowledge of the dung beetle fauna of El Salvador

Catalog and distribution atlas of the Scarabaeoidea (Insecta: Coleoptera) of El Salvador

Menos del 1% de la literatura sobre la biodiversidad de El Salvador es sobre invertebrados terrestres, lo que limita nuestro conocimiento de la diversidad, riqueza y distribución de este grupo en el territorio. Los Scarabaeoidea son megadiversos en múltiples ecosistemas y cumplen muchas funciones. Este trabajo tiene como objetivo catalogar los Scarabaeoidea en El Salvador. Se realizó una revisión exhaustiva de la literatura publicada y se revisaron numerosas colecciones entomológicas con material relevante. Se construyeron mapas para visualizar la distribución conocida de cada especie en el país. Existen 295 especies de escarabajos (incluyendo 19 nuevos registros en el país) representando 106 géneros en 7 familias en El Salvador. Se conocen seis especies precursoras. Veintidós especies se descartan como presentes en El Salvador, ya sea porque no son especies válidas o por identificaciones erróneas o registros dudosos. Este trabajo es la primera aproximación al conocimiento de los Scarabaeoidea en El Salvador, un territorio que usualmente se considera de nula importancia para la conservación de la biodiversidad regional debido a su reducida superficie, alta tasa de deforestación y sobrepoblación. Los resultados de este trabajo refuerzan la necesidad de realizar prospección biológica en el territorio para conocer, conservar y proteger la biodiversidad remanente. 2023 Universidad Nacional Autónoma de México. Todos los derechos reservados.Less than 1% of the literature on El Salvador s biodiversity is about terrestrial invertebrates, which limits our knowledge of this group s diversity, richness, and distribution in the territory. Scarabaeoidea are megadiverse in multiple ecosystems and perform many functions. This work aims to catalog the Scarabaeoidea in El Salvador. We conducted an exhaustive review of published literature and reviewed numerous entomological collections with relevant material. Maps were constructed to visualize the known distribution of each species in the country. There are 295 scarab beetle species (including 19 new country records) representing 106 genera in 7 families in El Salvador. Six precinctive species are known. Twenty-Two species are discarded as occurring in El Salvador, either because they are not valid species or because of misidentifications or dubious records. This work is the first approach to knowing the Scarabaeoidea in El Salvador, a territory that is usually considered of no importance for the conservation of regional biodiversity due to its small area, high rate of deforestation, and overpopulation. The results of this work reinforce the need for biological prospecting in the territory to know, conserve, and protect the remaining biodiversity. © 2023 Universidad Nacional Autonoma de Mexico. All rights reserved

Hacia una metodología estandarizada para el muestreo de escarabajos peloteros (Coleoptera: Scarabaeinae) en el Neotrópico: Una revisión crítica

Introducción: La estandarización de los protocolos de muestreo es imprescindible para el estudio robusto de cualquier grupo taxonómico. Los métodos replicables permiten la comparación de datos entre diferentes estudios espaciales y temporales. En el caso de los escarabajos coprófagos, uno de los grupos indicadores mejor estudiados en los análisis de perturbaciones ambientales, se utiliza una amplia gama de metodologías de recolección, desde trampas de caída básicas hasta métodos más complejos o complementarios, como el extractor mini-Winkler. Además, en los estudios de escarabajos coprófagos se utilizan diferentes tipos de cebos atractivos, esfuerzos de muestreo, duraciones y diseños. Las variaciones en los enfoques metodológicos se notan particularmente en el Neotrópico, lo que puede estar relacionado con la gran cantidad de estrategias biológicas y el comportamiento de los escarabajos coprófagos que habitan esta región. La falta de unificación metodológica para la región Neotropical imposibilita un análisis transversal de la información. Métodos: Realizamos una recopilación y revisión analítica de la literatura existente para el muestreo de escarabajos coprófagos en el Neotrópico, discutiendo las metodologías más utilizadas, sus ventajas y desventajas, y casos específicos en los que modelos particulares son más eficientes. Resultados: Las trampas Pitfall cebadas con excremento humano son el método de muestreo más común, pero existe una amplia gama de modelos y variaciones en la estructura de esta trampa. El efecto complementario generado por las trampas de interceptación de vuelos, las trampas de luz y las colecciones directas, particularmente dentro de los microhábitats, es emocionante por el potencial de encontrar nuevas especies. Algunas metodologías, como mini-Winkler extractor, fogging, o cebos muy específicos, se utilizan con poca frecuencia. Discusión: Hubo una falta de inclusión de la variación espacial y temporal entre los estudios. Por lo tanto, es necesario considerar ventanas de muestreo más amplias, que incluyan diferentes escalas espaciales, estaciones y años. Finalmente, proponemos un protocolo estándar para el muestreo de escarabajos coprófagos en el Neotrópico, dependiendo de cada objetivo, e incluyendo una metodología básica para la obtención de inventarios locales completos. Copyright © 2023 Mora-Aguilar, Arriaga-Jiménez, Correa, da Silva, Korasaki, López-Bedoya, Hernández, Pablo-Cea, Salomão, Valencia, Vulinec, Edwards, Edwards, Halffter y Noriega. Proponemos un protocolo estándar para el muestreo de escarabajos coprófagos en el Neotrópico, dependiendo de cada objetivo, e incluyendo una metodología básica para la obtención de inventarios locales completos. Copyright © 2023 Mora-Aguilar, Arriaga-Jiménez, Correa, da Silva, Korasaki, López-Bedoya, Hernández, Pablo-Cea, Salomão, Valencia, Vulinec, Edwards, Edwards, Halffter y Noriega. Proponemos un protocolo estándar para el muestreo de escarabajos coprófagos en el Neotrópico, dependiendo de cada objetivo, e incluyendo una metodología básica para la obtención de inventarios locales completos.Introduction: The standardization of sampling protocols is imperative for robustly studying any taxonomic group. Replicable methods allow the comparison of data between different spatial and temporal studies. In the case of dung beetles, one of the best-studied indicator groups in analyses of environmental disturbance, a wide range of collection methodologies are used, from basic pitfall traps to more complex or complementary methods such as mini-Winkler extractor. Also, different types of attractive baits, sampling effort, durations, and designs are used in dung beetle studies. Variations in methodological approaches are particularly noted in the Neotropics, which may be related to the vast number of biological strategies and behavior of dung beetles that inhabit this region. A lack of methodological unification for the Neotropical region makes a cross-sectional analysis of the information impossible. Methods: We performed a compilation and analytical review of the existing literature for dung beetle sampling in the Neotropics, discussing the most used methodologies, their advantages and disadvantages, and specific cases in which particular models are more efficient. Results: Pitfall traps baited with human excrement are the most common sampling method, but there is a wide range of models and variations in the structure of this trap. The complementary effect generated by flight interception traps, light traps, and direct collections, particularly within microhabitats, is exciting for the potential of finding new species. Some methodologies, such as mini-Winkler extractor, fogging, or very specific baits, are infrequently used. Discussion: There was a lack of inclusion of spatial and temporal variation among studies. Therefore, it is necessary to consider broader sampling windows, which include different spatial scales, seasons, and years. Finally, we propose a standard protocol for sampling dung beetles in the Neotropics, depending on each objective, and including a basic methodology for obtaining complete local inventories

Functional traits determine plant co-occurrence more than environment or evolutionary relatedness in global drylands

Plant–plant interactions are driven by environmental conditions, evolutionary relationships (ER) and the functional traits of the plants involved. However, studies addressing the relative importance of these drivers are rare, but crucial to improve our predictions of the effects of plant–plant interactions on plant communities and of how they respond to differing environmental conditions. To analyze the relative importance of – and interrelationships among – these factors as drivers of plant–plant interactions, we analyzed perennial plant co-occurrence at 106 dryland plant communities established across rainfall gradients in nine countries. We used structural equation modelling to disentangle the relationships between environmental conditions (aridity and soil fertility), functional traits extracted from the literature, and ER, and to assess their relative importance as drivers of the 929 pairwise plant–plant co-occurrence levels measured. Functional traits, specifically facilitated plants’ height and nurse growth form, were of primary importance, and modulated the effect of the environment and ER on plant–plant interactions. Environmental conditions and ER were important mainly for those interactions involving woody and graminoid nurses, respectively. The relative importance of different plant–plant interaction drivers (ER, functional traits, and the environment) varied depending on the region considered, illustrating the difficulty of predicting the outcome of plant–plant interactions at broader spatial scales. In our global-scale study on drylands, plant–plant interactions were more strongly related to functional traits of the species involved than to the environmental variables considered. Thus, moving to a trait-based facilitation/competition approach help to predict that: (1) positive plant–plant interactions are more likely to occur for taller facilitated species in drylands, and (2) plant–plant interactions within woody-dominated ecosystems might be more sensitive to changing environmental conditions than those within grasslands. By providing insights on which species are likely to better perform beneath a given neighbour, our results will also help to succeed in restoration practices involving the use of nurse plants

Surface indicators are correlated with soil multifunctionality in global drylands

Multiple ecosystem functions need to be considered simultaneously to manage and protect the several ecosystem services that are essential to people and their environments. Despite this, cost effective, tangible, relatively simple and globally relevant methodologies to monitor in situ soil multifunctionality, that is, the provision of multiple ecosystem functions by soils, have not been tested at the global scale. We combined correlation analysis and structural equation modelling to explore whether we could find easily measured, field-based indicators of soil multifunctionality (measured using functions linked to the cycling and storage of soil carbon, nitrogen and phosphorus). To do this, we gathered soil data from 120 dryland ecosystems from five continents. Two soil surface attributes measured in situ (litter incorporation and surface aggregate stability) were the most strongly associated with soil multifunctionality, even after accounting for geographic location and other drivers such as climate, woody cover, soil pH and soil electric conductivity. The positive relationships between surface stability and litter incorporation on soil multifunctionality were greater beneath the canopy of perennial vegetation than in adjacent, open areas devoid of vascular plants. The positive associations between surface aggregate stability and soil functions increased with increasing mean annual temperature. Synthesis and applications. Our findings demonstrate that a reduced suite of easily measured in situ soil surface attributes can be used as potential indicators of soil multifunctionality in drylands world-wide. These attributes, which relate to plant litter (origin, incorporation, cover), and surface stability, are relatively cheap and easy to assess with minimal training, allowing operators to sample many sites across widely varying climatic areas and soil types. The correlations of these variables are comparable to the influence of climate or soil, and would allow cost-effective monitoring of soil multifunctionality under changing land-use and environmental conditions. This would provide important information for evaluating the ecological impacts of land degradation, desertification and climate change in drylands world-wide.Fil: Eldridge, David J.. University of New South Wales; AustraliaFil: Delgado Baquerizo, Manuel. Universidad Rey Juan Carlos; EspañaFil: Quero, José L.. Universidad de Córdoba; EspañaFil: Ochoa, Victoria. Universidad Rey Juan Carlos; España. Universidad de Alicante; EspañaFil: Gozalo, Beatriz. Universidad Rey Juan Carlos; España. Universidad de Alicante; EspañaFil: García Palacios, Pablo. Universidad Rey Juan Carlos; EspañaFil: Escolar, Cristina. Universidad Rey Juan Carlos; EspañaFil: García Gómez, Miguel. Universidad Politécnica de Madrid; EspañaFil: Prina, Aníbal. Universidad Nacional de La Pampa; ArgentinaFil: Bowker, Mathew A.. Northern Arizona University; Estados UnidosFil: Bran, Donaldo Eduardo. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Norte. Estación Experimental Agropecuaria San Carlos de Bariloche; ArgentinaFil: Castro, Ignacio. Universidad Experimental Simón Rodríguez; VenezuelaFil: Cea, Alex. Universidad de La Serena; ChileFil: Derak, Mchich. No especifíca;Fil: Espinosa, Carlos I.. Universidad Técnica Particular de Loja; EcuadorFil: Florentino, Adriana. Universidad Central de Venezuela; VenezuelaFil: Gaitán, Juan José. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Suelos; Argentina. Universidad Nacional de Luján. Departamento de Tecnología; ArgentinaFil: Gatica, Mario Gabriel. Universidad Nacional de San Juan. Facultad de Ciencias Exactas Físicas y Naturales. Departamento de Biología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Centro de Investigaciones de la Geosfera y Biosfera. Universidad Nacional de San Juan. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones de la Geosfera y Biosfera; ArgentinaFil: Gómez González, Susana. Universidad de Cádiz; EspañaFil: Ghiloufi, Wahida. Université de Sfax; TúnezFil: Gutierrez, Julio R.. Universidad de La Serena; ChileFil: Guzman, Elizabeth. Universidad Técnica Particular de Loja; EcuadorFil: Hernández, Rosa M.. Universidad Experimental Simón Rodríguez; VenezuelaFil: Hughes, Frederic M.. Universidade Estadual de Feira de Santana; BrasilFil: Muiño, Walter. Universidad Nacional de La Pampa; ArgentinaFil: Monerris, Jorge. No especifíca;Fil: Ospina, Abelardo. Universidad Central de Venezuela; VenezuelaFil: Ramírez, David A.. International Potato Centre; PerúFil: Ribas Fernandez, Yanina Antonia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Centro de Investigaciones de la Geosfera y Biosfera. Universidad Nacional de San Juan. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones de la Geosfera y Biosfera; ArgentinaFil: Romão, Roberto L.. Universidade Estadual de Feira de Santana; BrasilFil: Torres Díaz, Cristian. Universidad del Bio Bio; ChileFil: Koen, Terrance B.. No especifíca;Fil: Maestre, Fernando T.. Universidad Rey Juan Carlos; España. Universidad de Alicante; Españ

Surface indicators are correlated with soil multifunctionality in global drylands

1. Multiple ecosystem functions need to be considered simultaneously to manage and protect the several ecosystem services that are essential to people and their environments. Despite this, cost effective, tangible, relatively simple and globally relevant methodologies to monitor in situ soil multifunctionality, that is, the provision of multiple ecosystem functions by soils, have not been tested at the global scale. 2. We combined correlation analysis and structural equation modelling to explore whether we could find easily measured, field‐based indicators of soil multifunctionality (measured using functions linked to the cycling and storage of soil carbon, nitrogen and phosphorus). To do this, we gathered soil data from 120 dryland ecosystems from five continents. 3. Two soil surface attributes measured in situ (litter incorporation and surface aggregate stability) were the most strongly associated with soil multifunctionality, even after accounting for geographic location and other drivers such as climate, woody cover, soil pH and soil electric conductivity. The positive relationships between surface stability and litter incorporation on soil multifunctionality were greater beneath the canopy of perennial vegetation than in adjacent, open areas devoid of vascular plants. The positive associations between surface aggregate stability and soil functions increased with increasing mean annual temperature. 4. Synthesis and applications. Our findings demonstrate that a reduced suite of easily measured in situ soil surface attributes can be used as potential indicators of soil multifunctionality in drylands world‐wide. These attributes, which relate to plant litter (origin, incorporation, cover), and surface stability, are relatively cheap and easy to assess with minimal training, allowing operators to sample many sites across widely varying climatic areas and soil types. The correlations of these variables are comparable to the influence of climate or soil, and would allow cost‐effective monitoring of soil multifunctionality under changing land‐use and environmental conditions. This would provide important information for evaluating the ecological impacts of land degradation, desertification and climate change in drylands world‐wide.This work was funded by the European Research Council ERC Grant agreement 242658 (BIOCOM). CYTED funded networking activities (EPES, Acción 407AC0323). D.J.E. acknowledges support from the Australian Research Council (DP150104199) and F.T.M. support from the European Research Council (BIODESERT project, ERC Grant agreement no 647038), from the Spanish Ministerio de Economía y Competitividad (BIOMOD project, ref. CGL2013-44661-R) and from a Humboldt Research Award from the Alexander von Humboldt Foundation. M.D.-B. was supported by REA grant agreement no 702057 from the Marie Sklodowska-Curie Actions of the Horizon 2020 Framework Programme H2020-MSCA-IF-2016), J.R.G. acknowledges support from CONICYT/FONDECYT no 1160026

Spatiotemporal Characteristics of the Largest HIV-1 CRF02_AG Outbreak in Spain: Evidence for Onward Transmissions

Background and Aim: The circulating recombinant form 02_AG (CRF02_AG) is the predominant clade among the human immunodeficiency virus type-1 (HIV-1) non-Bs with a prevalence of 5.97% (95% Confidence Interval-CI: 5.41–6.57%) across Spain. Our aim was to estimate the levels of regional clustering for CRF02_AG and the spatiotemporal characteristics of the largest CRF02_AG subepidemic in Spain.Methods: We studied 396 CRF02_AG sequences obtained from HIV-1 diagnosed patients during 2000–2014 from 10 autonomous communities of Spain. Phylogenetic analysis was performed on the 391 CRF02_AG sequences along with all globally sampled CRF02_AG sequences (N = 3,302) as references. Phylodynamic and phylogeographic analysis was performed to the largest CRF02_AG monophyletic cluster by a Bayesian method in BEAST v1.8.0 and by reconstructing ancestral states using the criterion of parsimony in Mesquite v3.4, respectively.Results: The HIV-1 CRF02_AG prevalence differed across Spanish autonomous communities we sampled from (p &lt; 0.001). Phylogenetic analysis revealed that 52.7% of the CRF02_AG sequences formed 56 monophyletic clusters, with a range of 2–79 sequences. The CRF02_AG regional dispersal differed across Spain (p = 0.003), as suggested by monophyletic clustering. For the largest monophyletic cluster (subepidemic) (N = 79), 49.4% of the clustered sequences originated from Madrid, while most sequences (51.9%) had been obtained from men having sex with men (MSM). Molecular clock analysis suggested that the origin (tMRCA) of the CRF02_AG subepidemic was in 2002 (median estimate; 95% Highest Posterior Density-HPD interval: 1999–2004). Additionally, we found significant clustering within the CRF02_AG subepidemic according to the ethnic origin.Conclusion: CRF02_AG has been introduced as a result of multiple introductions in Spain, following regional dispersal in several cases. We showed that CRF02_AG transmissions were mostly due to regional dispersal in Spain. The hot-spot for the largest CRF02_AG regional subepidemic in Spain was in Madrid associated with MSM transmission risk group. The existence of subepidemics suggest that several spillovers occurred from Madrid to other areas. CRF02_AG sequences from Hispanics were clustered in a separate subclade suggesting no linkage between the local and Hispanic subepidemics