695 research outputs found
Amendment application in a multicontaminated mine soil: Effects on trace element mobility
The final publication is available at Springer via http://dx.doi.org/10.1007/s11270-014-1874-4Several amendments were tested for their effectiveness in aiding plant growth and immobilising contaminants in pots containing soil from an arsenopyrite mine contaminated with arsenic and heavy metals. Trace element solubility in pore water was monitored using Rhizon samplers for five weeks. Results showed that amendments containing ferrous sulphate and ferrous sulphate combined with paper mill limited arsenic mobilisation and increased metal solubility. However, ferrous sulphate in combination with calcium carbonate was effective in reducing arsenic and metal solubilisation. Plant biomass of both the grass species used during the experiment, Arrhenatherum elatius and Festuca curvifolia, was a sensitive indicator of the comparative efficiency of the amendments, although metal(loid)s concentration in pore water did not correlate with plant uptakeThis study was supported by the Spanish Ministry of Science and Innovation, project COMFITES CTM2010-21922-C02-02; and by the Comunidad de Madrid, project EIADES S2009/AMB-147
Selección de plantas y enmiendas para la recuperación de suelos de mina contaminados con arsénico y metales pesado
Tesis doctoral inédita. Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Química Agrícola. Fecha de lectura: 04-11-201
The fate of arsenic in soils adjacent to an old mine site (Bustarviejo, Spain): Mobility and transfer to native flora
The final publication is available at Springer via http://dx.doi.org/10.1007/s11368-009-0099-4Background, aim, and scope The mobility of arsenic in soils and its transfer to other environmental components present significant environmental risks. The management of polluted land is determined by the availability, mobility, and transfer of inorganic pollutants to different ecosystem compartments. In this paper, the fate of arsenic at this mining site has been evaluated to determine future management practises to minimise such risk. Materials and methods In a field study carried out in the area adjacent to a mining site at Bustarviejo (North Madrid, Spain), samples of soils, plants, and water were collected from areas adjacent to the core of the former mining activity. The following parameters were investigated in soil samples: pH, organic matter, pseudo-total As, P, and Fe, and labile As and P, and a sequential extraction procedure was performed to investigate As speciation in soil. Plant materials were analysed for both As and P. Arsenic concentrations in water samples (surface and soil pore water collected in the field) were also measured. Results are considered in tandem with previous data on metal concentrations in soils and plants from this site. Results Despite high As concentrations in soils impacted by former mining activities (spoil accumulation and drainage from spoil heaps resulted in concentrations of up to 3,000 mg kg-1), it was not present in a labile form. Sequential extraction revealed that arsenic was mainly retained by Al- and Fe-(oxihydr)oxides (up to 80%). Therefore, only a small proportion of the total soil pool was potentially available for plant uptake (0.3% and 7% extracted by (NH4)2SO4 and NH4H2PO4, respectively). There was very limited transfer of arsenic from soil to plants, and concentrations of arsenic in shoot tissues were relatively low (<8 μg g-1). There was no evidence of phytotoxic effects in the flora that had colonised this site, indicating that a sustainable ecosystem had been established. Discussion High levels of arsenic occur at this site, but arsenic mobility appears to be primarily controlled by the presence of amorphous and crystalline Fe and Al hydrous oxides. Although a low labile As fraction was extracted, concentrations of arsenic in both surface and soil pore water are of concern. The risk of arsenic remobilisation by plant uptake or transfer to the food chain via plant consumption is relatively low in these soils. Large amounts of metals and arsenic remain at the site, and potential risks need to be monitored. Some possible remediation strategies that take into account the presence of both arsenic and heavy metals will be suggested. Recommendations Natural attenuation and phytostabilisation processes are taking place in several parts of the study area. These natural processes could be enhanced by application of both compost and a suitable Fe-based amendment. This augmentation of the re-vegetation of the affected area could act to promote both arsenic and metal stabilisation in mine tailings with additional benefits for further vegetation establishmentThis study was supported by the Spanish Ministry of Education and Science, project CTM 2007-66401-CO2/TECNO, and by Comunidad de Madrid, project S-0505/AMB/0296. The authors are grateful to the Excmo. Ayuntamiento de Bustarviejo, for admittance to the mine zone and the facilities offered and to Dr. R. Gamarra for his assistance with plant identification. Authors are grateful to L. Beesley for his comments and language corrections
Amendment application in a multi-contaminated mine soil: Effects on soil enzymatic activities and ecotoxicological characteristics
The final publication is available at Springer via http://dx.doi.org/10.1007/s11356-013-2412-4Several amendments were tested on soils obtained from an arsenopyrite mine, further planted with Arrhenatherum elatius and Festuca curvifolia, in order to assess their ability to improve soil's ecotoxicological characteristics. The properties used to assess the effects were: soil enzymatic activities (dehydrogenase, β-glucosidase, acid phosphatase, urease, protease and cellulase), terrestrial bioassays (Eisenia fetida mortality and avoidance behaviour), and aquatic bioassays using a soil leachate (Daphnia magna immobilisation and Vibrio fischeri bioluminescence inhibition). The treatment with FeSO4 1 % w/w was able to reduce extractable As in soil, but increased the extractable Cu, Mn and Zn concentrations, as a consequence of the decrease in soil pH, in relation to the unamended soil, from 5.0 to 3.4, respectively. As a consequence, this treatment had a detrimental effect in some of the soil enzymatic activities (e.g. dehydrogenase, acid phosphatase, urease and cellulase), did not allow plant growth, induced E. fetida mortality in the highest concentration tested (100 % w/w), and its soil leachate was very toxic towards D. magna and V. fischeri. The combined application of FeSO4 1 % w/w with other treatments (e.g. CaCO3 1 % w/w and paper mill 1 % w/w) allowed a decrease in extractable As and metals, and a soil pH value closer to neutrality. As a consequence, dehydrogenase activity, plant growth and some of the bioassays identified those as better soil treatments to this type of multi-contaminated soi
The Andean Condor (Vultur gryphus): ¿predator or scavenger? Plurality of perceptions between local knowledge and academic discourse in the central hills of Argentina
Este trabajo explora las percepciones relacionadas con el Cóndor Andino (Vultur gryphus) a través del conocimiento tradicional, las prácticas del habitante rural y el discurso académico asociado a la especie. El estudio se desarrolló en cuatro áreas de las sierras centrales de Argentina, en las provincias de Catamarca, Córdoba (Parque Nacional Quebrada del Condorito), La Rioja y San Juan. Desde la mirada de estos actores sociales, el Cóndor Andino puede ser valorado como una especie clave, emblemática y digna de conservar, pero también puede ser considerada como conflictiva y que debe ser eliminada por el comportamiento cazador que le adjudican algunos lugareños. Por medio de técnicas etnográficas se obtuvo información que evidenció la existencia de una pluralidad en las apreciaciones vinculadas con el Cóndor Andino, considerando los discursos locales y los provenientes del ámbito académico. Se destacan especialmente las percepciones diferenciales referentes a sus hábitos alimentarios, encontrando un contraste entre las narrativas en las que coinciden la percepción conservacionista de los pobladores del parque nacional y la academia, y la mirada de los pobladores de las otras tres áreas de estudio. Los datos sistematizados muestran la simultaneidad de percepciones asociadas a los saberes individuales y colectivos sobre la relación entre el ser humano y el animal, identificando aspectos que van desde los criterios asociados a la importancia biocultural y la conservación del ave, hasta su valoración negativa por ser considerada una amenaza para la producción ganadera.This work explores perceptions related to the Andean Condor (Vultur gryphus) through the traditional knowledge, the practices of the rural inhabitant and the academic discourse associated to the species. The study was carried out in four areas of the central hills of Argentina, in the provinces of Catamarca, Córdoba (Quebrada del Condorito National Park), La Rioja and San Juan. From the perspective of these social actors, the Andean Condor can be valued as a key species, emblematic and worthy of conservation, but it can also be considered as conflictive and that must be eliminated by the hunter behaviour that some locals attribute to it. By means of ethnographic techniques we obtained information that evidenced the existence of a plurality in evaluations related to the Andean Condor, considering the local and the academic discourses, especially the differential perceptions regarding their eating habits, finding a contrast between the narratives in which the conservationist perception of the settlers of the park and the academy coincides, and the view of the settlers of the other three study areas. Systematized data show the simultaneity of perceptions associated with individual and collective knowledge about the human–animal relationship, identifying aspects ranging from the criteria associated with biocultural importance and conservation of the bird, until its negative valuation by being considered a threat for the livestock production.Fil: Manzano García, Jessica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Antropología de Córdoba. Universidad Nacional de Córdoba. Facultad de Filosofía y Humanidades. Instituto de Antropología de Córdoba; ArgentinaFil: Jiménez Escobar, Néstor David. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Antropología de Córdoba. Universidad Nacional de Córdoba. Facultad de Filosofía y Humanidades. Instituto de Antropología de Córdoba; ArgentinaFil: Lobo Allende, Rebeca. Universidad Nacional de Chilecito; ArgentinaFil: Cailly Arnulphi, Verónica Beatríz. 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; Argentin
El ordenamiento territorial y su papel en la construcción de lugares saludables, caso: zona metropolitana de Toluca, México
El objetivo de este trabajo es analizar el papel de la ordenación territorial en la construcción de lugares saludables, ante problemas ambientales y socioeconómicos que inciden negativamente en la salud de la población. Se considera un diagnóstico de las características socio-económicas, ambientales y de salud de la población de la Zona Metropolitana de Toluca (ZMT). Metodología. Se trata de un estudio descriptivo, de carácter trans-seccional y el tipo de investigación es cuantitativo. Las fuentes de información son: imágenes de satélite, cartografía temática, Anuario Estadístico del Estado de México del Instituto Nacional de Estadística y Geografía (INEGI, 2011) y datos del Instituto de Salud del Estado de México (ISEM), entre otras fuentes. Entre los resultados principales de la investigación destaca el hecho de que se trata de municipios con grado de marginación muy bajo y bajo; grado de rezago social muy bajo y medio; índice de desarrollo humano medio alto y alto; actividades económicas principalmente en servicios e industria; sin embargo se presentan problemas ambientales como erosión y falta de espacios verdes, así como tasas de mortalidad altas principalmente de tipo crónico degenerativo como la diabetes mellitus, enfermedades isquémicas del corazón, tumores malignos y cirrosis y otras enfermedades del hígado. Ante estos problemas la ordenación territorial juega un papel importante en la generación de propuestas estratégicas focalizadas, en la creación de lugares saludables con un enfoque holístico y regional
Las crisis bancarias de 2023: causas y papel de los gestores bancarios, los supervisores y los reguladores
Artículo de revistaLos eventos observados en el año 2023 han servido como recordatorio de la rapidez con la que pueden suceder las crisis bancarias. Este artículo realiza un análisis de las raíces de los problemas que, finalmente, en un contexto de incertidumbre y de rápidos efectos de contagio, afectaron a entidades que presentaban debilidades significativas en su modelo de negocio, su gobernanza y su gestión de riesgos. El artículo también revisa las principales implicaciones para el sector bancario y para las autoridades a nivel internacional. Así, estos hechos recuerdan, de nuevo, que la actividad bancaria se debe sustentar en modelos de negocio sostenibles en el tiempo y en una apropiada gestión de riesgos. Además, se vuelve a poner de manifiesto la importancia de que la actividad supervisora esté dotada de las herramientas adecuadas para garantizar su reacción temprana y efectiva. Por último, aunque la regulación vigente ha ayudado a frenar el alcance sistémico de las crisis gracias al aumento de la resiliencia del sector bancario, reforzando así de nuevo la necesidad de implementar el marco de Basilea III, hay algunas áreas donde resulta oportuno seguir analizando el funcionamiento del marco regulatorio prudencial
Impact of bisphosphonates on the proliferation and gene expression of human fibroblasts
The aim of this study was to elucidate the role of fibroblasts in bisphosphonate-related
osteonecrosis of the jaw (BRONJ), evaluating the effect of zoledronate, alendronate, and
ibandronate on the proliferation of fibroblasts and on their expression of genes essential for
fibroblast physiology. Human CCD-1064Sk epithelial fibroblast cells were incubated in culture
medium with 10-5, 10-7, or 10-9 M zoledronate, alendronate, or ibandronate. The proliferative
capacity of fibroblasts was determined by spectrophotometry (MTT) at 24 of culture. Real-time
polymerase chain reaction (RT-PCR) was used to study the effects of BPs at a dose of 10-9 M on the
expression of FGF, CTGF, TGF-β1, TGFβR1, TGFβR2, TGFβR3, DDR2, α-actin, fibronectin,
decorin, and elastin. Fibroblasts proliferation was significantly increased at the lowest dose (10-9M)
of each BP but was not affected at the higher doses (10-5 and 10-7M). The proliferation increase may
be related to the rise in TGF-β1 and TGFβR1 expression detected after the treatment of cells with
10-9M of zoledronate, alendronate, or ibandronate. However, the expression of CTGF, DDR2,
α-actin, fibronectin, and decorin decreased versus controls. The results of this in vitro study indicate
that a very low BP dose (10-9 M) can significantly affect the physiology of fibroblasts, increasing their
proliferative capacity and modulating the expression of multiple genes involved in their growth and
differentiation
Bone Protective Effect of Extra-Virgin Olive Oil Phenolic Compounds by Modulating Osteoblast Gene Expression
The phenolic compounds of extra-virgin olive oil can act at various levels to protect
individuals against cardiovascular and neurodegenerative diseases, cancer, and osteoporosis, among
others. Polyphenols in extra-virgin olive oil can stimulate the proliferation of osteoblasts, modify
their antigen profile, and promote alkaline phosphatase synthesis. The objective of this work was to
determine the effect of different extra-virgin olive oil phenolic compounds on the gene expression
of osteoblast-related markers. The cells of the MG63 osteoblast line were cultured for 24 h with
10-6 M of the phenolic compounds ferulic acid, caffeic acid, coumaric acid, apigenin, or luteolin.
The expression of studied markers was quantified using quantitative real-time polymerase chain
reaction (q-RT-PCR). The expression by MG63 osteoblasts of growth and differentiation/maturation
markers was modified after 24 h of treatment with 10-6 M of the phenolic compounds under study,
most of which increased the gene expression of the transforming growth factor 1 (TGF- 1), TGF-
receptor 1,2 and 3 (TGF- R1, TGF- R2, TGF- R3), bone morphogenetic protein 2 and 7 (BMP2,
BMP7), run-related transcription factor 2 (RUNX-2), Alkaline phosphatase (ALP), Osteocalcin (OSC),
Osterix (OSX), Collagen type I (Col-I) and osteoprotegerin (OPN). The extra-virgin olive oil phenolic
compounds may have a beneficial effect on bone by modulating osteoblast physiology, which would
support their protective effect against bone pathologies.The work outlined in this article has been partially funded by the Spanish Ministry of Education under
FPU fellowship reference FPU15-0563
Human Fibroblast Gene Expression Modulation Using 940 NM Diode Laser
Low-Level Laser Therapy is used as regenerative therapy in different clinical fields. This is due to its
photobiomodulation effect via cell signaling on different cell populations, Including fibroblasts, cells
involved in tissue regeneration and healing. The aim was to analyze the effect of 940 nm diode laser on
the gene expression of different markers involved in fibroblast growth, differentiation, and migration.
Real-time polymerase chain reaction (q-RT-PCR) was used to quantify the expression of fibroblast
growth factor (FGF), connective tissue growth factor (CTGF), vascular-endothelial growth factor
(VEGF), transforming growth factor β1 (TGF-β1), TGFβ-receptors (TGFβR1, TGFβR2, and TGFβR3),
discoidin-domain receptor-2 (DDR2), matrix metalloproteinase-2 (MMP2), α-actin, fibronectin, decorin,
and elastin on human fibroblast, treated with single dose (T1) or two doses (T2) of diode laser at 0.5
Watts and 4 J/cm2. A significant increase in the expression of FGF, TGF-β1, TGFβR1, TGFβR2, α-actin,
fibronectin, decorin, DDR2 and MMP2 was observed after both treatments. A decrease was observed
in expression of elastin (T1 and T2), and CTGF (T2). These changes underlie the biostimulatory effect
of laser on fibroblasts, which translates into an increase in short-term proliferation and in long-term
differentiation to myofibroblasts. These data support the therapeutic potential of diode laser for wound
repair
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