2,215 research outputs found
Sobre la gestión del patrimonio natural y el paisaje en España en la era de los Espacios Naturales Protegidos: el caso de los invertebrados
In the last decades, as far as management of the natural heritage is concerned, Protected Natural Areas have gained great importance in conservation biology as they have been established as valuable conservation management areas for fauna and flora species. These spaces are often surrounded by farming and stockbreeding areas, with which they form landscape units of high relevance for biodiversity conservation. To analyze the role of these landscape units as mosaics of interconnected areas of interest to wildlife species and communities of high ecological value constitutes a necessary and general interest aim concerning the sustainable management of the landscape and natural heritage. These circumstances apply to many populations of invertebrates and insects within such landscape units, previously in the background with respect to other elements that have generated more social or scientific interest, owing to their crucial role in the maintenance of ecosystem diversity and population flow inside and outside the Protected Natural Areas, and also because they sometimes constitute biodiversity units upon which the management of these spaces has been based. In this paper, we try to show, through the case of Lepidoptera (Hexapoda), the importance of an integrated management of natural heritage and landscape in Spain for the conservation of invertebrates and insects, all within the context of conservation biology.En las últimas décadas, en lo que a gestión del patrimonio natural se refiere, el papel de los Espacios Naturales Protegidos ha cobrado una gran relevancia en el campo de la biología de la conservación al constituirse como áreas gestionadas para la conservación de especies de flora y fauna. Estos espacios se encuentran en muchos casos rodeados de zonas de aprovechamiento de recursos agroganaderos, con las cuales forman unidades de paisaje de gran importancia para el mantenimiento de la biodiversidad. Analizar el papel de estas unidades de paisaje como áreas interconectadas en mosaico y de interés para especies y comunidades de fauna de alto valor ecológico representa un objetivo necesario y de interés general para la gestión sostenible del paisaje y el patrimonio natural. Sobre muchas poblaciones de invertebrados e insectos dentro de estas unidades de paisaje, aun estando en un segundo plano respecto a otros elementos que han despertado mayor interés social o científico, confluyen tales circunstancias, por su papel determinante en el mantenimiento de la diversidad de ecosistemas y flujo de sus poblaciones dentro y fuera de los Espacios Naturales Protegidos, y el hecho de que a veces constituyen unidades de biodiversidad sobre las que se ha basado la gestión de estos espacios. En el presente texto, a través del caso de los Lepidoptera (Hexapoda) se pretende poner de manifiesto la importancia que tiene para la conservación de los invertebrados e insectos una gestión integral del patrimonio natural y el paisaje de nuestro país, todo ello dentro del contexto de la biología de la conservación
Drosophila Imaginal Discs as a Playground for Genetic Analysis: Concepts, Techniques and Expectations for Biomedical Research
Drosophila imaginal discs are epithelial tissues perfectly suited to use them as a playground to define the functional contribution of genes to epithelial development and organ morphogenesis. The more we know about the discs and the mechanisms directing their development, the best prepared we are to assign specific “functions” to individual genes based on phenotypic observations. Conversely, and thinking from the perspective of the gene, the more we know about its function, the best inferences we could make about the mechanisms underlying imaginal disc development. This reciprocal relationship, coupled to the arsenal of possible experimental approaches available in Drosophila genetics, genomics and cellular biology, makes these tissues excellent systems to address biological problems with biomedical relevance. In this review, an overview of three interconnected aspects related to the use of Drosophila imaginal discs as an experimental system to analyze gene function is given: (i) imaginal discs biology, with a focus in the genetic mechanisms involved in pattern formation; (ii) concepts and available experimental tools for the analyses of gene function and (iii) uses of Drosophila and the imaginal discs for addressing biomedical problems
Wastewater treatment using microalgae: how realistic a contribution might it be to significant urban wastewater treatment?
Microalgae have been proposed as an option for wastewater treatment since the 1960’s but still this technology has not been expanded to an industrial scale. In this paper, the major factors limiting the performance of these systems are analysed. The composition of the wastewater is highly relevant, and especially the presence of pollutants such as heavy metals and emerging compounds. Biological and engineering aspects are also critical and have to be improved to at least approximate the performance of conventional systems, not just in terms of capacity and efficiency but also in terms of robustness. Finally, the harvesting of the biomass and its processing into valuable products poses a challenge; yet at the same time, an opportunity exists to increase economic profitability. Land requirement is a major bottleneck that can be ameliorated by improving the system’s photosynthetic efficiency. Land requirement has a significant impact on the economic balance but the profits from the biomass produced can enhance these systems’ reliability, especially in small cities
Covalent functionalization of N-doped graphene by N-alkylation
[EN] Nitrogen doped graphene was modified by N-alkylation using a combination of phase transfer catalysis and microwave irradiation. The resulting derivatives of N-doped graphene were analysed showing that the bandgap of the material varied depending on the alkylation agent used.Financial support from MINECO (Spain) (CTQ2013-48252-P and CTQ2012-32315), Junta de Comunidades de Castilla-La Mancha (PEII-2014-014-P) and Generalidad Valenciana (Prometeo 13/19) is gratefully acknowledged. M.B. thanks the MINECO for a doctoral FPI grant.Barrejon, M.; Primo Arnau, AM.; Gomez-Escalonilla, M.; Fierro, JLG.; García Gómez, H.; Langa, F. (2015). Covalent functionalization of N-doped graphene by N-alkylation. Chemical Communications. 51(95):16916-16919. https://doi.org/10.1039/c5cc06285cS16916169195195Wang, H., Maiyalagan, T., & Wang, X. (2012). Review on Recent Progress in Nitrogen-Doped Graphene: Synthesis, Characterization, and Its Potential Applications. 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From biomass wastes to large-area, high-quality, N-doped graphene: catalyst-free carbonization of chitosan coatings on arbitrary substrates. Chemical Communications, 48(74), 9254. doi:10.1039/c2cc34978gPrimo, A., Sánchez, E., Delgado, J. M., & García, H. (2014). High-yield production of N-doped graphitic platelets by aqueous exfoliation of pyrolyzed chitosan. Carbon, 68, 777-783. doi:10.1016/j.carbon.2013.11.068Wang, X., Sun, G., Routh, P., Kim, D.-H., Huang, W., & Chen, P. (2014). Heteroatom-doped graphene materials: syntheses, properties and applications. Chem. Soc. Rev., 43(20), 7067-7098. doi:10.1039/c4cs00141aWu, M., Cao, C., & Jiang, J. Z. (2010). Light non-metallic atom (B, N, O and F)-doped graphene: a first-principles study. Nanotechnology, 21(50), 505202. doi:10.1088/0957-4484/21/50/505202Rani, P., & Jindal, V. K. (2013). Designing band gap of graphene by B and N dopant atoms. 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Selection of native Tunisian microalgae for simultaneous wastewater treatment and biofuel production
This paper focuses on the selection of native microalgae strains suitable for wastewater treatment and biofuel production. Four Chlorophyceae strains were isolated from North-eastern Tunisia. Their performances were compared in continuous mode at a 0.3 1/day dilution rate. The biomass productivity and nutrient removal capacity of each microalgae strain were studied. The most efficient strain was identified as Scenedesmus sp. and experiments at different dilution rates from 0.2 to 0.8 1/day were carried out. Maximal biomass productivity of 0.92 g/L·day was obtained at 0.6 1/day. The removal of chemical oxygen demand (COD), ammonium and phosphorus was in the range of 92-94%, 61-99% and 93-99%, respectively. Carbohydrates were the major biomass fraction followed by lipids and then proteins. The saponifiable fatty acid content was in the 4.9-13.2% dry biomass range, with more than 50% of total fatty acids being composed of saturated and monosaturated fatty acids
Utilization of secondary-treated wastewater for the production of freshwater microalgae
In this work we studied the potential use of secondary-treated wastewater as nutrient source in the production of freshwater microalgae strains. Experiments were performed indoors in semicontinuous mode, at 0.3 day-1, simulating outdoor conditions. We demonstrated that all the tested strains can be produced by using only secondary-treated wastewater as the nutrient source. The utilization of secondary-treated wastewater imposes nutrient-limiting conditions, with maximal biomass productivity dropping to 0.5 g·l-1·day-1and modifies the biochemical composition of the biomass by increasing the amount of lipids and carbohydrates while reducing the biomass protein content. We measured fatty acids content and productivity of up to 25%d.wt. and 110 mg·l-1·day-1, respectively. We demonstrated that all the tested strains were capable of completely removing the nitrogen and phosphorus contained in the secondary-treated wastewater, and while the use of this effluent reduced the cells’ photosynthetic efficiency, the nitrogen and phosphorus coefficient yield increased. Muriellopsis sp. and S. subpicatus were selected as the most promising strains for outdoor production using secondary-treated wastewater as the culture medium; this was not only because of their high productivity but also their photosynthetic efficiency, of up to 2.5%, along with nutrient coefficient yields of up to 96 gbiomass·gN-1 and 166 gbiomass·gP-1. Coupling microalgae production processes to tertiary treatment in wastewater treatment plants makes it possible to recover nutrients contained in the water and to produce valuable biomass, especially where nutrient removal is required prior to wastewater discharge
A low-mass planet candidate orbiting Proxima Centauri at a distance of 1.5 AU
Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).Our nearest neighbor, Proxima Centauri, hosts a temperate terrestrial planet. We detected in radial velocities evidence of a possible second planet with minimum mass m c sin i c = 5.8 ± 1.9 M ⊕ and orbital period P c = 5.21 - 0.22 + 0.26 years. The analysis of photometric data and spectro-scopic activity diagnostics does not explain the signal in terms of a stellar activity cycle, but follow-up is required in the coming years for confirming its planetary origin. We show that the existence of the planet can be ascertained, and its true mass can be determined with high accuracy, by combining Gaia astrometry and radial velocities. Proxima c could become a prime target for follow-up and characterization with next-generation direct imaging instrumentation due to the large maximum angular separation of ~1 arc second from the parent star. The candidate planet represents a challenge for the models of super-Earth formation and evolution.Peer reviewedFinal Published versio
Aridity could have driven the local extinction of a common and multivoltine butterfly
1.Identifying which species are being negatively impacted by climate change and the mechanisms driving their decline is essential to effectively protect biodiversity.
2.Coenonympha pamphilus is a common and generalist butterfly, widely distributed throughout the Western Palearctic, being multivoltine in southern Europe. Previous studies indicate that it will not be substantially affected by climate change; however, it has seemingly disappeared from the southeast of the Iberian Peninsula in the last decades.
3. Here, we aim to determine if it has effectively disappeared from this area, as well as identify the environmental conditions limiting its distribution and the potential causes behind this a priori local extinction.
4.We downloaded all the occurrence records of C. pamphilus and analysed their spatial and temporal trends. To identify the climatic variables driving the distribution of this butterfly in the Iberian Peninsula, we performed an ensemble species distribution model (SDM), combining 600 individual models produced with 6 algorithms.
5.We confirmed that C. pamphilus has not been observed in the southeast of the Iberian Peninsula since 2008. Aridity was the main factor limiting the distribution of C. pamphilus in our ensemble SDM, with areas with high aridity being unsuitable for this species.
6. We hypothesise that multivoltinism is the mechanism driving this local extirpation, as high aridity is causing host plants (Poaceae) to wither prematurely, precluding the development of the second and/or third generations of the butterfly. Even though generalist species are theoretically more resilient to climate change, other traits such as multivoltinism may increase their vulnerability and need to be further investigated
Crowd Monitoring in Smart Destinations Based on GDPR-Ready Opportunistic RF Scanning and Classification of WiFi Devices to Identify and Classify Visitors’ Origins
Crowd monitoring was an essential measure to deal with over-tourism problems in urban destinations in the pre-COVID era. It will play a crucial role in the pandemic scenario when restarting tourism and making destinations safer. Notably, a Destination Management Organisation (DMO) of a smart destination needs to deploy a technological layer for crowd monitoring that allows data gathering in order to count visitors and distinguish them from residents. The correct identification of visitors versus residents by a DMO, while privacy rights (e.g., Regulation EU 2016/679, also known as GDPR) are ensured, is an ongoing problem that has not been fully solved. In this paper, we describe a novel approach to gathering crowd data by processing (i) massive scanning of WiFi access points of the smart destination to find SSIDs (Service Set Identifier), as well as (ii) the exposed Preferred Network List (PNL) containing the SSIDs of WiFi access points to which WiFi-enabled mobile devices are likely to connect. These data enable us to provide the number of visitors and residents of a crowd at a given point of interest of a tourism destination. A pilot study has been conducted in the city of Alcoi (Spain), comparing data from our approach with data provided by manually filled surveys from the Alcoi Tourist Info office, with an average accuracy of 83%, thus showing the feasibility of our policy to enrich the information system of a smart destination.This research was carried out within the research Project Alcoi Tourist Lab framework, co-funded by the Alcoi City Council & the Valencian Innovation Agency. The research was also partially funded by project UAPOSTCOVID19-10 from the University of Alicante. Finally, this research was partly supported by the EU CEF project GreenMov, CARM HORECOV-21 project (https://horecovid.com/ (accessed on 12 January 2022)). is financed through the Call for Public Aid destined to finance the Strategic projects contemplated in the Research and Innovation Strategy for Smart Specialization - RIS3MUR Strategy by the Autonomous Community of the Region of Murcia, through the Ministry of Economic Development, Tourism and Employment within the framework of the FEDER Region of Murcia Operational Program 2014–2020 within the framework Thematic Objective 1. Strengthen research, technological development and innovation by 80% and with CARM’s own funds in 20%, and finally the EU project H2020 NIoVE (833742)
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