Empleo de isótopos ambientales para discernir la contaminación salina de la cuenca del río Llobregat

La formación geológica salina de la comarca del Bages(Barcelona) y su explotación minera en diferentes puntos de la cuenca del Llobregat, influyen en la salinización de los ríos Cardener y Llobregat. La cuenca potásica catalana presenta dos peculiaridades: la formación salina tiene un afloramiento en Cardona, y en algunas zonas las capas de mineral se encuentran cerca de la superficie pero sin aflorar. La geología del terreno puede influir en la salinidad de las aguas de la cuenca por contacto directo con los materiales salinos. La actividad minera de Cardona (cerrada en 1990), Suria,Balsareny y Sallent, genera en la producción del mineral un residuo salino que se acumula en el exterior de las minas formándose las escombreras salinas o «runams». Sus salessolubles se disuelven con la lluvia, y pueden llegar a las aguas superficiales y aguas subterráneas del entorno. El objetivo de este trabajo es evaluar las aportaciones salinas a la cuenca del río Llobregat, separando las de origen natural y las de procedencia antrópica, utilizando la composición isotópica del azufre y del oxigeno del sulfato disuelto en sus aguas. También se cuantifica el origen natural y antrópico de los cloruros que se aportan

Do Thiols Merely Passivate Gold Nanoclusters?

A Comment on the Letter by H. Hakkinen, R. N. Barnett, and U. Landman, Phys. Rev. Lett. 82, 3264 (1999)

Integrating dual C and N isotopic approach to elemental and mathematical solutions for improving the PM source apportionment in complex urban and industrial cities: Case of Tarragona - Spain

Identification of dominant airborne Particulate Matter (PM) sources is essential for maintaining high air quality standards and thus ensuring a good public health. In this study, different approaches were applied for source apportionment of three PM fractions (PM1, PM2.5 and PM10) at the outdoor of 14 schools of a coastal city with a significant land use interweaving such as Tarragona (Spain). PM were collected in 24h-quartz microfiber filters in two seasonal campaigns (cold and warm), together with nine local potential sources, so a total of 84 samples were chemically, mineralogically, and isotopically characterised. Source apportionment was assessed by (i) main chemical components, (ii) Principal Component Analysis (PCA), (iii) dual C and N isotope approach, and (iv) a Bayesian isotope mixing model. When chemical concentrations were grouped into marine, crustal, secondary inorganic aerosols and organic matter + elemental carbon categories, the unaccounted component reached 45% of PM mass. The PCA allowed to identify also traffic and industrial contributions, reducing the unaccounted mass to about 25%. Adding δ13C and δ15N values, secondary organic aerosol could be estimated and a continuous contribution of diesel combustion was identified together with a remarkable use of natural gas in winter. Isotopic values were better understood when considering air masses back trajectories and a possible long-distance contribution from coal-fired electric generating units (EGUs). Finally, using Bayesian dual isotope mixing models, the unaccounted PM mass was reduced up to 5% when adding these EGUs to marine-carbonate related, road traffic, domestic heating, waste incinerator and livestock waste contributions. The added value of the dual isotope approach combined with a Bayesian isotope mixing model, in comparison with conventional chemical approaches, was thus demonstrated for PM source apportionment in an urban and industrial site where many sources and processes converge and can then be applied to other complex cities

Recuperación de un suelo afectado por incendio con compost de residuos sólidos urbanos: respuesta microbiana y enzimática

Ponencia presentada en la IX Reunión Nacional Científico Técnica de Biología de Suelos. I Congreso Nacional de Biología Molecular de Suelos. Santiago del Estero, Argentina, 4 al 6 de septiembre de 2013Se estudió el efecto de la incorporación de enmiendas orgánicas compost sobre las propiedades microbiológicas y enzimáticas de un suelo forestal afectado por incendio. Se determinaron contenido de carbono de biomasa microbiana, respiración y actividades enzimáticas tales como deshidrogenasa, ureasa, fosfatasa y proteasa. El agregado de compost provenientes de residuos sólidos urbanos en dosis de 90 Tn/Ha genero una mejora de la actividad microbiana del suelo estudiado.Fil: Campitelli, Paola Andrea. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; Argentina.Fil: Soler-Rovira, Pedro. Consejo Superior de Investigaciones Científicas. Instituto de Ciencias Agrarias; España.Fil: Ceppi, Silvia Beatriz. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; Argentina.Fil: García-Gil Gallegos, J.C. Consejo Superior de Investigaciones Científicas. Instituto de Ciencias Agrarias; España

Height and timing of growth spurt during puberty in young people living with vertically acquired HIV in Europe and Thailand.

OBJECTIVE: The aim of this study was to describe growth during puberty in young people with vertically acquired HIV. DESIGN: Pooled data from 12 paediatric HIV cohorts in Europe and Thailand. METHODS: One thousand and ninety-four children initiating a nonnucleoside reverse transcriptase inhibitor or boosted protease inhibitor based regimen aged 1-10 years were included. Super Imposition by Translation And Rotation (SITAR) models described growth from age 8 years using three parameters (average height, timing and shape of the growth spurt), dependent on age and height-for-age z-score (HAZ) (WHO references) at antiretroviral therapy (ART) initiation. Multivariate regression explored characteristics associated with these three parameters. RESULTS: At ART initiation, median age and HAZ was 6.4 [interquartile range (IQR): 2.8, 9.0] years and -1.2 (IQR: -2.3 to -0.2), respectively. Median follow-up was 9.1 (IQR: 6.9, 11.4) years. In girls, older age and lower HAZ at ART initiation were independently associated with a growth spurt which occurred 0.41 (95% confidence interval 0.20-0.62) years later in children starting ART age 6 to 10 years compared with 1 to 2 years and 1.50 (1.21-1.78) years later in those starting with HAZ less than -3 compared with HAZ at least -1. Later growth spurts in girls resulted in continued height growth into later adolescence. In boys starting ART with HAZ less than -1, growth spurts were later in children starting ART in the oldest age group, but for HAZ at least -1, there was no association with age. Girls and boys who initiated ART with HAZ at least -1 maintained a similar height to the WHO reference mean. CONCLUSION: Stunting at ART initiation was associated with later growth spurts in girls. Children with HAZ at least -1 at ART initiation grew in height at the level expected in HIV negative children of a comparable age

Impacts of Use and Abuse of Nature in Catalonia with Proposals for Sustainable Management

This paper provides an overview of the last 40 years of use, and in many cases abuse, of the natural resources in Catalonia, a country that is representative of European countries in general, and especially those in the Mediterranean region. It analyses the use of natural resources made by mining, agriculture, livestock, logging, fishing, nature tourism, and energy production and consumption. This use results in an ecological footprint, i.e., the productive land and sea surface required to generate the consumed resources and absorb the resulting waste, which is about seven times the amount available, a very high number but very similar to other European countries. This overexploitation of natural resources has a huge impact on land and its different forms of cover, air, and water. For the last 25 years, forests and urban areas have each gained almost 3% more of the territory at the expense of agricultural land; those municipalities bordering the sea have increased their number of inhabitants and activity, and although they only occupy 6.7% of the total surface area, they account for 43.3% of the population; air quality has stabilized since the turn of the century, and there has been some improvement in the state of aquatic ecosystems, but still only 36% are in good condition, while the remainder have suffered morphological changes and different forms of nonpoint source pollution; meanwhile the biodiversity of flora and fauna remains still under threat. Environmental policies do not go far enough so there is a need for revision of the legislation related to environmental impact and the protection of natural areas, flora, and fauna. The promotion of environmental research must be accompanied by environmental education to foster a society which is Land 2021, 10, 144 3 of 53 more knowledgeable, has more control and influence over the decisions that deeply affect it. Indeed, nature conservation goes hand in hand with other social and economic challenges that require a more sustainable vision. Today’s problems with nature derive from the current economic model, which is environmentally unsustainable in that it does not take into account environmental impacts. Lastly, we propose a series of reasonable and feasible priority measures and actions related to each use made of the country’s natural resources, to the impacts they have had, and to their management, in the hope that these can contribute to improving the conservation and management of the environment and biodiversity and move towards sustainability.info:eu-repo/semantics/publishedVersio

Height and timing of growth spurt during puberty in young people living with vertically acquired HIV in Europe and Thailand

Objective: The aim of this study was to describe growth during puberty in young people with vertically acquired HIV. Design: Pooled data from 12 paediatric HIV cohorts in Europe and Thailand. Methods: One thousand and ninety-four children initiating a nonnucleoside reverse transcriptase inhibitor or boosted protease inhibitor based regimen aged 1-10 years were included. Super Imposition by Translation And Rotation (SITAR) models described growth from age 8 years using three parameters (average height, timing and shape of the growth spurt), dependent on age and height-for-age z-score (HAZ) (WHO references) at antiretroviral therapy (ART) initiation. Multivariate regression explored characteristics associated with these three parameters. Results: At ART initiation, median age and HAZ was 6.4 [interquartile range (IQR): 2.8, 9.0] years and -1.2 (IQR: -2.3 to -0.2), respectively. Median follow-up was 9.1 (IQR: 6.9, 11.4) years. In girls, older age and lower HAZ at ART initiation were independently associated with a growth spurt which occurred 0.41 (95% confidence interval 0.20-0.62) years later in children starting ART age 6 to 10 years compared with 1 to 2 years and 1.50 (1.21-1.78) years later in those starting with HAZ less than -3 compared with HAZ at least -1. Later growth spurts in girls resulted in continued height growth into later adolescence. In boys starting ART with HAZ less than -1, growth spurts were later in children starting ART in the oldest age group, but for HAZ at least -1, there was no association with age. Girls and boys who initiated ART with HAZ at least -1 maintained a similar height to the WHO reference mean. Conclusion: Stunting at ART initiation was associated with later growth spurts in girls. Children with HAZ at least -1 at ART initiation grew in height at the level expected in HIV negative children of a comparable age