EDXRF study of Tupi-Guarani archaeological ceramics.

A set of indian Brazilian pottery fragments belonging to Tupi-Guarani tradition has been studied by an archaeometric non-destructive technique. The pottery fragments were accidentally discovered in the Santa Dalmacia farm, sited near Cambé city at the north of Paraná Brazilian state. Each one of these fragments came from different ceramic recipients and their physical characteristics are very similar. The EDXRF measurements were performed employing both an X-ray tube and three radioisotope sources (Fe, Cd and Pu). The compositional data of the ceramics paste and pigments is investigated. For detection of the elements within the ceramic paste, the fragments were irradiated at the center of the lateral section, while several superficial areas with remaining plastic decoration were also chosen and irradiated at the convex and concave sides of each fragment. A paste-subtracted compositional data of the remaining pigments was statically extracted from the XRF analysis of each area. A program based on the graphic polygonal representation method was developed and used to correlate the representative intensity data of each fragment.Um conjunto de fragmentos cerâmicos indígenas brasileiros pertencentes à Tradição Tupi-Guarani foi estudado por uma técnica arqueométrica não destrutiva. Os fragmentos cerâmicos foram descobertos acidentalmente na fazenda Santa Dalmácia, situada próximo da cidade de Cambé, no norte do estado do Paraná. Cada um desses fragmentos veio de diferentes recipientes cerâmicos e suas características físicas são muito similares. As medidas EDXRF foram realizadas empregando tanto um tubo de raios X como três fontes de radioisótopos (55Fe, 109Cd e 238Pu). Os dados de composição da pasta cerâmica e dos pigmentos são investigados. Para detecção dos elementos contidos na pasta cerâmica, os fragmentos foram irradiados no centro da secção lateral, enquanto algumas áreas com decoração plástica remanescente também foram escolhidas e irradiadas nos lados convexo e côncavo de cada fragmento. Foram obtidas as composições dos pigmentos remanescentes em cada área analisada, subtraindo-se do espectro XRF da área considerada o espectro XRF da pasta cerâmica. Um programa baseado no método de representação poligonal gráfica foi desenvolvido e usado para correlacionar a intensidade representativa de cada fragmento

Transportability of non-target arthropod field data for the use in environmental risk assessment of genetically modified maize in Northern Mexico

In country, non-target arthropod (NTA) field evaluations are required to comply with the regulatory process for cultivation of genetically modified (GM) maize in Mexico. Two sets of field trials, Experimental Phase and Pilot Phase, were conducted to identify any potential harm of insect-protected and glyphosate-tolerant maize (MON89Ø34-3 × MON-88Ø17-3 and MON-89Ø34-3 × MON-ØØ6Ø3-6) and glyphosatetolerant maize (MON-ØØ6Ø3-6) to local NTAs compared to conventional maize. NTA abundance data were collected at 32 sites, providing high geographic and environmental diversity within maize production areas from four ecological regions (ecoregions) in northern Mexico. The most abundant herbivorous taxa collected included field crickets, corn flea beetles, rootworm beetles, cornsilk flies, aphids, leafhoppers, plant bugs and thrips while the most abundant beneficial taxa captured were soil mites, spiders, predatory ground beetles, rove beetles, springtails (Collembola), predatory earwigs, ladybird beetles, syrphid flies, tachinid flies, minute pirate bugs, parasitic wasps and lacewings. Across the taxa analysed, no statistically significant differences in abundance were detected between GM maize and the conventional maize control for 69 of the 74 comparisons (93.2%) indicating thatthe single or stacked insect-protected and herbicide-tolerant GM traits generally exert no marked adverse effects on the arthropod populations compared with conventional maize. The distribution of taxa observed in this study provides evidence that irrespective of variations in overall biodiversity of a given ecoregion, important herbivore, predatory and parasitic arthropod taxa within the commercial maize agroecosystem are highly similar indicating that relevant data generated in one ecoregion can be transportable for the risk assessment of the same or similar GM crop in another ecoregion

Pigmentos lipossolúveis e hidrossolúveis em plantas de salvínia sob toxicidade por cromo

Devido à intensa utilização industrial, o cromo é considerado um importante poluente ambiental. O presente trabalho objetivou determinar os teores de pigmentos hidro e lipossolúveis em plantas de salvínia expostas a concentrações crescentes de Cr, visando estabelecer parâmetros bioquímicos para utilização dessa macrófita em programas de biomonitoramento e/ou fitorremediação da poluição causada por esse poluente metálico em ambientes aquáticos. As plantas foram submetidas a concentrações crescentes de Cr e avaliadas após quatro, seis e dez dias de tratamento. Os resultados dos ensaios permitiram concluir que plantas de salvínia sob condições de estresse por Cr apresentam reduções nas concentrações das clorofilas a, b e total e, em contraste, aumentos nas concentrações de antocianinas totais. Embora a concentração de carotenoides totais não tenha sido alterada em resposta ao Cr, as variações nas concentrações dos demais pigmentos lipossolúveis e dos pigmentos hidrossolúveis observadas nas folhas das plantas de salvínia podem ser utilizadas como parâmetros bioquímicos de biomonitoramento da poluição causada por esse elemento metálico em ambientes aquáticos.Due to widespread industrial use, chromium is considered a serious environmental pollutant. This study aimed to determine the content of hydrosoluble and liposoluble pigments in salvinia plants exposed to increasing concentrations of Cr, to establish biochemical parameters for the use of macrophyta in pollution bio-monitoring programs and/or phyto-remediation in aquatic environments by this pollutant metal. The plants were exposed to increasing concentrations of Cr and evaluated after four, six, and ten days of treatment. The test results showed that salvinia plants under stress conditions for Cr exhibit decreases in the concentrations of chlorophylls a, b, and total, and, in contrast, increases in anthocyanin concentrations. Although the concentration of carotenoids has not been altered in response to Cr, the variations in the concentrations of other liposoluble and hydrosoluble pigments found in salvinia plant leaves can be used as biochemical parameters for biomonitoring of pollution caused by this metallic element in aquatic environments

Performance evaluation of different solar advanced oxidation processes applied to the treatment of a real textile dyeing wastewater

The performance of different solar-driven advanced oxidation processes (AOPs), such as TiO2/UV, TiO2/H2O2/UV, and Fe2+/H2O2/UV-visible in the treatment of a real textile effluent using a pilot plant with compound parabolic collectors (CPCs), was investigated. The influence of the main photo-Fenton reaction variables such as iron concentration (20-100 mg Fe2+ L-1), pH (2.4-4.5), temperature (10-50 °C), and irradiance (22-68 WUV m-2) was evaluated in a lab-scale prototype using artificial solar radiation. The real textile wastewater presented a beige color, with a maximum absorbance peak at 641 nm, alkaline pH (8.1), moderate organic content (dissolved organic carbon (DOC) = 129 mg C L-1 and chemical oxygen demand (COD) = 496 mg O2 L-1), and high conductivity mainly associated to the high concentration of chloride (1.1 g Cl- L-1), sulfate (0.4 g SO 4 2 - L- 1), and sodium (1.2 g Na+ L-1) ions. Although all the processes tested contributed to complete decolorization and effective mineralization, the most efficient process was the solar photo-Fenton with an optimum catalyst concentration of 60 mg Fe2+ L-1, leading to 70 % mineralization (DOCfinal = 41 mg C L-1; CODfinal < 150 mg O2 L-1) at pH 3.6, requiring a UV energy dose of 3.5 kJUV L-1 (t30 W = 22.4 min; (Formula presented.); (Formula presented.)) and consuming 18.5 mM of H2O2. (c) 2014 Springer-Verlag Berlin Heidelberg

SACI - A 4π plastic phoswich array ancillary detector system of a γ-ray spectrometer

A large solid angle low-Z charged particle detector system was built in order to improve the quality of the identification and selection of evaporation channels for in-beam γ-spectroscopy measurements. The array consists of 11 plastic phoswich telescopes closely packed in a 4π arrangement and to be used as an ancillary system for the Pelletron Laboratory γ-ray spectrometer. The new system was tested in γ-particle and γ-γ-particle coincidence measurements using the 27Al + 16O and 100Mo + 11B reactions, at 53 and 43 MeV incident beam energies, respectively. The values for the particle detection efficiency and improvement in the peak to background ratios are considered acceptable for the usefulness of the system. © 2002 Elsevier Science B.V. All rights reserved