2,926 research outputs found

    The collection of amphibians from Madrid at the Museo Nacional de Ciencias Naturales and its utility in conservation

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    [EN] We present the revised catalogue of the amphibians deposited in the “Colección de Anfibios y Reptiles” of the Museo Nacional de Ciencias Naturales that have been collected in the Comunidad Autónoma of Madrid. It consists of 2272 records of 18 species, including all species present in Madrid except Hyla meridionalis. We evaluate the collection on the basis of the representation of the specimens collected in relation with: 1) the present distribution of each amphibian species in Madrid, considering the number of UTM 10x10 km grid cells represented in the collection in relation with the total number of grids occupied by each species in Madrid; 2) the number of intraspecific subunits that are relevant from a conservation perspective (subspecies or groups of populations that are differentiated on ecological or genetic grounds) that are represented in the collection. Representation values range from 0% (Hyla meridionalis) to 50% (Triturus alpestris). We also include information on the conservation status of some populations from historical collection sites and conclude that at least 10 breeding sites have disappeared as a consequence of human activities, with the subsequent local extinction of their associated amphibian populations. We have also documented the disappearance of some species from unaltered areas. Finally, we discuss the utility of scientific collections in facing practical aspects of the management and conservation of endangered groups like amphibians.[ES] Se presenta el catálogo revisado de los anfibios de la Colección de Anfibios y Reptiles del Museo Nacional de Ciencias Naturales colectados en la Comunidad de Madrid. En total, consta de 2272 entradas correspondientes a 18 especies, que incluyen todas las presentes en la Comunidad excepto Hyla meridionalis. Se valora la colección en función del grado de representatividad de los ejemplares de la colección en relación con: 1) la distribución actual de las especies de anfibios en Madrid, considerando el % de cuadrículas UTM de 10x10 km del total del área de distribución de cada especie que se encuentran representadas en la colección; 2) el número de unidades infraespecíficas relevantes desde el punto de vista de la conservación (subespecies o grupos de poblaciones diferenciados ecológica o genéticamente) representados en la colección para cada especie. Los valores de representatividad obtenidos oscilan entre el 0% (Hyla meridionalis) y el 50% (Triturus alpestris). Además, se aporta información acerca de algunas de las poblaciones asentadas en los lugares de colecta históricos, lo que permite concluir que al menos 10 puntos de reproducción han desaparecido durante los últimos años como resultado de la actividad humana, con la consiguiente extinción local de esas poblaciones de anfibios. Por otro lado, en ciertos casos también se ha documentado la desaparición de especies en áreas aparentemente inalteradas. Finalmente, se discute la utilidad de las colecciones museológicas para afrontar aspectos prácticos relacionados con la gestión y conservación de grupos amenazados como los anfibios.El trabajo de IMS estáfinanciado por una beca predoctoral MNCN-CSIC-CAM.Peer reviewe

    Efficiency of Combined Processes Coagulation/Solar Photo Fenton in the Treatment of Landfill Leachate

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    The combined coagulation-solar photo Fenton treatment of leachate from the sanitary landfill located in Atlantico-Colombia was investigated. Firstly, the efficiency of two alternative combined treatments for the reduction of chemical oxygen demand in leachate was assessed, coagulation with poly-aluminum chloride followed by solar photo-Fenton process (Treatment 1) and coagulation with FeCl3·6H2O followed by ferrioxalate-induced solar photo-Fenton process (Treatment 2). Afterwards, treatments 1 and 2 were compared with the treatment currently used in the sanitary landfill (only coagulation with poly-aluminum chloride), in terms of efficiency and costs. An optimization study of alternative treatments was performed combining central-composite experimental design and response surface methodology. The optimum conditions resulted in a chemical oxygen demand reduction of 73 % and 80 % for Treatment 1 and 2, respectively. Both alternative treatments for the leachate are more efficient than the treatment currently used in the sanitary landfill (chemical oxygen demand reduction of 20 %). In terms of costs, treatment 1 would be the most competitive to implement in the sanitary landfill, since this would have an increase of 13.3 % in the total unitary cost compared to an increase of 39.5 % of treatment 2

    Effect of irrigation with treated wastewater on microbiological quality of the soil and King Grass

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    La contaminación del agua utilizada en el mundo y la falta de plantas de tratamiento altamente eficientes plantean problemas potenciales para la salud pública y el medio ambiente, por lo que los países buscan métodos confiables, inocuos y eficaces en función de los costos, para depurar las aguas residuales. Por otro lado, el sector agropecuario ha tomado auge, dada la necesidad de implementación de técnicas limpias, que sean amigables con el medio ambiente. El riego con aguas residuales en la agricultura, se ha vuelto común en regiones áridas y semiáridas, debido a la baja disponibilidad de agua, pero su uso requiere de un monitoreo cuidadoso de parámetros de higiene. El objetivo de este trabajo fue analizar el efecto del riego, con aguas residuales tratadas, sobre la contaminación microbiológica del suelo y el pasto King Grass, además de la producción de materia seca del forraje. Se evaluaron tres tratamientos: tratamiento T1: sin riesgo (SR), T2: agua subterránea (AS) y T3: agua residual tratada (ART). Se hicieron análisis fisicoquímicos y microbiológicos al agua, suelo y pasto. La contaminación microbiológica en el suelo regado con agua residual tratada no presentó diferencias significativas (p>0,05) frente a los suelos donde se aplicó riego con agua subterránea, así como tampoco se presentaron diferencias estadísticas significativas entre variables microbiológicas en pasto. Se concluyó, que la fuente de contaminación microbiológica de los pastos y el suelo no está relacionada únicamente con la carga microbiana presente en las aguas residuales, sino que se puede deber, entre otros factores, a las escorrentías y al uso de aguas subterráneas contaminadas para el riegoWorld water contamination and the lack of wastewater treatment plants pose potential problems concerning public health and on the environment. Therefore, countries are looking for reliable, safe and cost-effective methods to purify wastewater. On the other hand, the agricultural sector has taken a lot of momentum given the need to implement clean techniques that are friendly to the environment. boomed given the need to implement clean techniques that are friendly to the environment. Wastewater irrigation in agriculture has become common in arid and semi-arid regions due to low water availability, but its use requires careful monitoring of hygiene parameters. The objective of this work was to analyze the effect of treated wastewater on microbiological contamination of the soil and King grass, in addition to the production of dry matter from forage. Were evaluated three treatments: T1: no risk; T2: groundwater and T3: treated wastewater. Were made physicochemical and microbiological analyzes out on water, soil and grass. The microbiological contamination in the soil irrigated with treated wastewater did not show significant differences compared to the soils where irrigation with groundwater was applied, as well as there were no statistical differences between microbiological variables in grass. It was concluded that the source of microbiological contamination of pastures and soil is not only related to the microbial load present in the wastewater, but it may be due, among other factors, to runoff and the use of contaminated groundwater for irrigatio

    Microplastic pollution in sublittoral coastal sediments of a North Atlantic island: The case of La Palma (Canary Islands, Spain)

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    In this work, the microplastic content of sediments collected in July 2020 between 5 and 7 m depth was studied in four locations of La Palma island (Canary Islands, Spain). At each sampling location, three samples were taken parallel to the shoreline. The microplastic content in each sampling corer was studied every 2.5 cm depth after digestion with a H2O2 solution followed by flotation in a saturated NaCl solution. Visualization of the final filtrates under a stereomicroscope revealed that all the sediment samples evaluated contained mostly microfibers (98.3%) which were mainly white/colorless (86.0%) and blue (9.8%), with an average length of 2423 ± 2235 (SD) mm and an average concentration of 2682 ± 827 items per kg of dry weight, being the total number of items found 1,019. Fourier Transform Infrared microscopy analysis of 13.9% (n = 139) of the microfibers also showed that they were mainly cellulosic (81.3%). No significant differences were found between the depths of the sediment. However, significant differences were found between the number of fibers from the sampling sites at the east and west of the island. Such variability could be driven by the winds and ocean mesoscale dynamics in the area. This study confirms the wide distribution of microfibers in sediments from an oceanic island like La Palma, providing their first report in marine sediments of the Canary Islands.En prensa3,20

    Photovoice: An active learning tool with community nursing students

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    Objective: To assess nursing students’ experiences of using photovoice as a pedagogical approach to active learning in the community. Methods: A descriptive design with a cross-sectional mixed-method questionnaire was used with 108 students following an educational activity, in which their communities were photographed and the impact of the pandemic on vulnerable populations was reflected. Descriptive statistics and thematic analysis were used to analyze the data. Results: Seventy eight percent of the students felt that photovoice was an interesting and useful tool for nurses, 89% affirmed it helped stimulate reflection on social and health inequities in times of pandemic, 82% described that it developed many emotions and feelings and 86% would like to disseminate their photographs directly to stakeholders, citizens, and politicians. Three themes were identified in the data: “stimulate critical reflection”, “develop emotional skills”, and “encourage action”. Conclusions: Photovoice is a successful active learning pedagogical approach that engages nursing students to develop critical awareness while connecting with their communities, with the real world. It fosters students' sensitivity and motivation and encourages them to take action. Teachers need to introduce new scaffolds for active learning, such as photovoice, to provide innovative academic support that nurtures and develops the next generation of nurses appropriately

    Obtaining lipids and carbohydrates from microalgae via design of selective culture media

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    La producción sostenible de biorrefinerías a partir de microalgas presenta varias complicaciones técnicas a diferentes niveles, entre los que se encuentra la maximización de la productividad de bloques energéticos, como carbohidratos y lípidos, que sean materia prima para biodiesel y bioetanol. Una alternativa para aumentar la productividad de bloques energéticos es el uso de cultivos alternativos a los medios químicos tradicionales, los cuales se han basado en fuentes de carbono, fosforo, nitrógeno y microelementos. Este trabajo presenta el diseño de dos medios de cultivo mixotrófico con diferentes fuentes de carbono, nitrógeno y fósforo, a fin de evaluar la producción de carbohidratos y lípidos a partir de Chlorella vulgaris. Los medios de cultivo se diseñaron a diferentes concentraciones de nitrato de sodio, fosfato de potasio y acetato de sodio/carbonato de amonio como fuente de carbono. Además, se realizaron diagramas de Pareto y Superficies de Respuesta utilizando el software estadístico STATISTICA 7.0, a fin de conocer la influencia significativa de las variables de estudio sobre la producción de metabolitos. Los resultados mostraron que la concentración de los nutrientes en los cultivos mixotroficos afecta la producción de metabolitos, para el caso de la obtención de carbohidratos, el acetato, el carbonato y el fosfato ejercieron un efecto positivo en su producción. Para la producción de lípidos, cuando el medio de cultivo contenía acetato, no se presentó variable alguna que influyera significativamente, mientras que, para el cultivo con carbonato de amonio, el nitrato y las interacciones carbonato-fosfato, nitrato-fosfato ejercieron una influencia significativa en la producción de este metabolito.Sustainable production of microalgae biorefineries presents several technical bottlenecks in different levels, including maximization of productivity of energy blocks as carbohydrates and lipids, which can be used as feedstocks for biodiesel and bioethanol production. An alternative for increasing productivity of energy blocks is the use of alternative crops to traditional chemical media, which are based on carbon, phosphorus, nitrogen sources and microelements. This work presents the design of two mixotrophic crops were designed at different concentrations of carbon, nitrogen and phosphate sources with the aim of evaluating the carbohydrates and lipids production from Chlorella vulgaris. The culture media were designed at different concentrations of sodium nitrate, potassium phosphate and sodium acetate / ammonium carbonate as carbon source. In addition, Pareto charts and Response Surface were performed using the statistical software STATISTICA 7.0, in order to know the significant influence of study variables on metabolites production. Results showed that the concentration of nutrients in the mixotrophic cultures affect the production of metabolites, for the case of carbohydrates production, acetate, carbonate and phosphate had a positive effect on it. Regarding lipids production, when the culture media contained acetate, there was not any variable that influenced significantly, whereas for the cultivation with ammonium carbonate, nitrate and interactions carbonate-phosphate, nitrate-phosphate had a significant influence on production of this metabolite

    SNP markers found in non-coding regions can distinguish among low-variant genotypes of arabica and other coffee species.

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    Development of efficient and scalable methods for molecular identification of Coffea spp. are necessary to accelerate studies related to the characterization of germplasm for both conservation or breeding purposes, and the validation of coffee germplasm. The low genetic diversity of coffee hinders the establishment of protocols that facilitate the molecular characterization of a given genotype. In this study, nucleotide variability was analyzed at 22 loci in the genome of 19 coffee accessions using de novo primer sets and high-resolution melting (HRM). Single nucleotide polymorphisms (SNPs) variants were studied in coding regions of genes implicated in sucrose accumulation in the seed, Sucrose synthase 2 (SUS2), Ent-kaurene oxidase 1 (CaKO1), and Caffeoyl-coenzyme A 3-O-methyltransferase (CcOAOMT). The non-coding Internal transcribed spacer 2 (ITS2) region was also studied. Variability was shown at 103 positions both at the interspecies level (15 loci) and among varieties of Coffea arabica L. (4 loci). The HMR technique for identification of variants in genes CaKO1, SUS2, CcoAOMT, as well as in the ITS2 region proved to be a robust technique for germplasm characterization. More important this technique can be used for fingerprinting and traceability of coffee grain exports which is an increasing market-consumer demand
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