Cálculo y emisiones de CO₂ en materiales propios de la arquitectura (vernácula e industrial)

Sumario: 1.Introducción 1.1 Fuentes de energía y producción de materiales 1.2 Emisiones de CO₂ y normativas 2. Metodología y resultados 2.1 Criterios de para el cálculo de emisiones de CO₂ en la edificación 2.2 Meta criterio de cálculo de emisiones de CO2 en la energía embebida en la edificación 2.3 Discusión 3. ConclusionesFacultad de Arquitectura y Urbanism

Comparison of the Condition Factor of Five Fish Species of the Araguaia River Basin, Central Brazil

This study aims to assess the condition factor (K) of five fish species (Serrasalmus rhombeus, Psectrogaster amazonica, Loricaria cataphracta, Panaque nigrolineatus and Squaliforma emarginata). Samplings were conducted during the low-water period of 2007 and 2008 using gillnets and minnow traps. All equipments were placed along a stretch of 1000 m at 5 pm and retrieved at 7 am. Collected fish were taxonomically identified, weighed (g) and measured (standard length; mm). The fish fitness was assessed by the condition factor (K=W/L³) and compared among groups of tributaries by a Kruskal-Wallis test. From the five species considered, two (S. emarginata and P. amazonica) displayed significant differences of the condition factor among the groups of tributaries. The highest values of K correspond to fish located in the headwaters, while lowest values are observed in tributaries located in the floodplain.Este estudo objetiva avaliar o fator de condição (K) de cinco espécies de peixes (Serrasalmus rhombeus, Psectrogaster amazonica, Loricaria cataphracta, Panaque nigrolineatus e Squaliforma emarginata). As coletas foram realizadas utilizando-se quatro jogos de redes de malhar e cinco armadilhas, os quais foram colocados ao longo de um trecho de 1000 m das 17:00 às 7:00. Os peixes coletados foram identificados taxonomicamente, pesados (g) e medidos (comprimento standard; mm). A condição física dos peixes foi calculada pelo fator de condição (K=W/L³) e comparada por grupo de cursos de água utilizando um teste de Kruskal-Wallis. Das cinco espécies consideradas S. emarginata e P. amazonica mostraram diferenças na condição física por grupo de cursos de água. Os maiores valores de K de ambas as espécies correspondem aos espécimes localizados em cursos de água de cabeceira, enquanto que baixos valores são encontrados em peixes dos cursos de água na planície

HPLC and FTIR Characterization of Aqueous Extracts of Three Diuretic Plant Species from West Central Argentina

Euphorbia serpens Kunth var. microphylla Müll. Arg. (Euphorbiaceae), Amaranthus muricatus (Moq.) Hieron. (Amaranthaceae) y Lithraea molleoides (Vell.) Engl. (Anacardiaceae) son plantas usadas tradicionalmente en el Cono Sur de América como diuréticas. Las dos primeras son hierbas denominadas vulgarmente “yerbas meonas”, mientras que la última, un árbol perennifolio, es conocido como “molle de beber” o “molle dulce”. El objeto de este trabajo es caracterizar los extractos acuosos de estas drogas vegetales, identificando y cuantificando manitol por HPLC, debido a que este alcohol sería el principal responsable de la actividad diurética que han mostrado las tres plantas. Se realizó además, la caracterización fisicoquímica de las especies vegetales por comparación de los espectros de FT-IR. Los cromatogramas obtenidos por HPLC muestran picos con tiempos de retención a 35,44 min (estándar) característicos para manitol, y el área por debajo de las respectivas curvas permitió establecer concentraciones respecto a materia seca entre 23,056 g Kg-1 en E. serpens var. microphylla; 4,638 g Kg-1 en L. molleoides; y 2,080 g Kg-1 en A. muricatus. Estas cifras explican las diferencias en la potencia diurética descripta en la bibliografía para las especies en estudio. Los espectros IR presentan una relación de áreas de las bandas CO/CH que resultó distintiva para las dos especies (8,42 para E. serpens var. microphylla; 9,28 para A. muricatus; y 11,18 para L. molleoides). El valor mayor correspondiente a L. molleoides indica mayor cantidad de compuestos oxigenados. Los datos espectrales obtenidos permiten contribuir a la caracterización de los extractos acuosos de estas especies y aportan datos para un control de calidad efectivo de las drogas vegetales y los medicamentos herbarios que los contengan en su formulación.Euphorbia serpens Kunth var. microphylla Müll. Arg. (Euphorbiaceae), Amaranthus muricatus(Moq.) Hieron. (Amaranthaceae), and Lithraea molleoides (Vell.) Engl. (Anacardiaceae) are traditionally used in Southern South America as diuretic plants. The first two are herbs commonly called “yerbas meonas”, while the latter an evergreen tree, is known as “molle de beber” or “molle dulce”. This work tends to characterize the aqueous extracts (AEs) of these plant drugs, identifying and quantifying mannitol by HPLC, since this alcohol would be primarily responsible for the diuretic activity shown in the three plants. Furthermore, to characterize the species by comparing their FT-IR spectra. The HPLC spectra show the characteristic areas for mannitol at retention time (Tr) 35.44 min, while the area under the respective curves allowed to establish varying concentrations among 23.056 g Kg-1 on the basis of dry matter in E. serpens var. microphylla, 4.638 g Kg-1 in L. molleoides, and 2.080 g Kg-1 in the case of A. muricatus. These figures explain the differences in diuretic potency described in the literature for these species. The FTIR spectra show CO/CH relations which are characteristic for each species (8.42 for E. serpens var. microphylla; 9.28 for A. muricatus; and 11.18 for L. molleoides); the higher value corresponding to L. molleoides indicates a greater amount of oxygenates. The spectral data obtained allow us to contribute to the characterization of AEs of these species, and provide data for effective quality control.Fil: Garro, Maria Filomena. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Gette, Maria de Los Angeles. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Petenatti, Marta E.. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia; ArgentinaFil: Popovich, Mariana C.. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia; ArgentinaFil: Cami, Gerardo. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia; ArgentinaFil: Saidman, Elbio. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia; ArgentinaFil: del Vitto, Luis Angel. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Petenatti, Elisa. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia; Argentin

Inventario de emisiones a la atmósfera de compuestos orgánicos persistentes seleccionados en Mendoza para el año 2011

El presente trabajo trata la identificación y análisis de fuentes específicas de Contaminantes Orgánicos Persistentes junto con el cálculo de sus emisiones, en el área del Gran Mendoza, durante el año 2011. Se estimaron las emisiones de Bifenilos Policlorados (PCB), Hexaclorobenceno (HCB), y Diclorodifeniltricloroetano (DDT). Debido a la gran variedad de fuentes y compuestos involucrados y a limitaciones en la disponibilidad de información, no se utilizó un método armonizado para todos los compuestos en la preparación del inventario. Los datos presentados en este estudio proporcionan un panorama general de las emisiones en el Gran Mendoza. Finalmente, se destaca la necesidad de un esfuerzo mayor en la caracterización y validación de las emisiones, tanto para la obtención de relaciones entre fuentes y receptores, como también para el desarrollo de estrategias de control. Asimismo, esta información es crucial para lograr una reducción en la carga de estas sustancias, a nivel local y regional.The present work is focused on the identification and analysis of specific sources of Permanent Organic Pollutants together with the calculation of emissions in the Great Mendoza during 2011. Emissions of polychlorinated biphenyls (PCBs), hexachlorobenzene (HCB) and Dichloro-diphenyl-trichloroethane (DDT) were estimated. Due to the wide variety of sources and compounds involved and the limited availability of information, a harmonized method for all compounds in the preparation of the inventory was not used. Data submitted in this study provide an overview of the emissions in the Great Mendoza urban area. Finally, great efforts in the characterization and validation of emissions, both for obtaining relationships between sources and sinks, as well as for the development of strategies to control them are needed. Also, this information is crucial to achieve a reduction in the burden of these substances, at local and regional level.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES

The effect of water molecules on paraquat salts: from physicochemical properties to environmental impact in the Brazilian Cerrado

Introduction: The green revolution model that is followed in the Brazilian Cerrado is dependent on mechanization, chemical fertilization for soil dressing and correction, and the use of herbicides. Paraquat is a methyl viologen herbicide marketed as bipyridylium dichloride salts and used (in low doses) to combat weeds in their post-emergence stage. It is a non-selective pesticide that causes the peroxidation of the lipids that make up the cell membrane, and when it comes into contact with foliage, it results in the death of the plant.Methods: The effect of water molecules co-crystallized in Paraquat salt structures was analyzed in anhydrous, dihydrate, and trihydrate forms to understand those physicochemical properties in its redox activity. The frontier molecular orbitals were also carried out using DFT to obtain the chemical reactivity of the bipyridylium cation. Finally, the supramolecular arrangements were evaluated to analyze the physicochemical stability and acquire insights on superoxide anions.Results and discussion: The electronic structure indicated that the BP cation presents an acidic character due to its low ELUMO value, while the salt has a more basic character due to its high EHOMO value. For this reason, the BP ion is more susceptible to reduction during the weeds’ photosynthesis process. During the process of plant photosynthesis, PQ is reduced to form a stable radical cation. In the supramolecular arrangement, the presence of water molecules increases the number of strong H-bonds, while the weak/moderate H-bonds are stabilized. PQ’s toxic effects are observed in wildlife, domesticated animals, human populations, and ecosystems. The influence of PQ on the terrestrial environment is limited because of the soil adsorption capacity associated with good agricultural practices. The current use of good agricultural practices in the Cerrado seems not to prevent the environmental impacts of herbicides like PQ because it aims for the expansion and profitability of large-scale farming based on input-intensive practices instead of sustainable agriculture processes

Author correction : a global database for metacommunity ecology, integrating species, traits, environment and space

Correction to: Scientific Data https://doi.org/10.1038/s41597-019-0344-7, published online 08 January 202

Author correction : a global database for metacommunity ecology, integrating species, traits, environment and space

Correction to: Scientific Data https://doi.org/10.1038/s41597-019-0344-7, published online 08 January 202

Discovery of new globular clusters in the Sagittarius dwarf galaxy

© ESO 2021. Published by EDP Sciences. This is the accepted manuscript version of an article which has been published in final form at https://doi.org/10.1051/0004-6361/202140395Context. Globular clusters (GCs) are witnesses of the past accretion events onto the Milky Way. In particular, the GCs of the Sagittarius (Sgr) dwarf galaxy are important probes of an on-going merger. Aims. Our main goal is to search for new GC members of this dwarf galaxy using the VISTA Variables in the Via Lactea Extended Survey (VVVX) near-infrared database combined with the Gaia Early Data Release 3 (EDR3) optical database. Methods. We investigated all VVVX-enabled discoveries of GC candidates in a region covering about 180 sq. deg. toward the bulge and the Sgr dwarf galaxy. We used multiband point-spread function photometry to obtain deep color-magnitude diagrams (CMDs) and luminosity functions (LFs) for all GC candidates, complemented by accurate Gaia-EDR3 proper motions (PMs) to select Sgr members and variability information to select RR Lyrae which are potential GC members. Results. After applying a strict PM cut to discard foreground bulge and disk stars, the CMDs and LFs for some of the GC candidates exhibit well defined red giant branches and red clump giant star peaks. We selected the best Sgr GCs, estimating their distances, reddenings, and associated RR Lyrae. Conclusions. We discover 12 new Sgr GC members, more than doubling the number of GCs known in this dwarf galaxy. In addition, there are 11 other GC candidates identified that are uncertain, awaiting better data for confirmation.Peer reviewedFinal Accepted Versio