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Registros recuperados: 61 | |
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Sussarellu, Rossana; Lebreton, Morgane; Rouxel, Julien; Akcha, Farida; Riviere, Guillaume. |
Copper contamination is widespread along coastal areas and exerts adverse effects on marine organisms such as mollusks. In the Pacific oyster, copper induces severe developmental abnormalities during early life stages; however, the underlying molecular mechanisms are largely unknown. This study aims to better understand whether the embryotoxic effects of copper in Crassostrea gigas could be mediated by alterations in gene expression, and the putative role of DNA methylation, which is known to contribute to gene regulation in early embryo development. For that purpose, oyster embryos were exposed to 4 nominal copper concentrations (0.1, 1, 10 and 20 μg L−1 Cu2+) during early development assays. Embryotoxicity was monitored through the oyster embryo-larval... |
Tipo: Text |
Palavras-chave: Oyster; Embryotoxicity; Copper; Gene expression; DNA methylation. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00417/52856/53756.pdf |
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Pratap, H.B.; Mamboya, F.A.; Mtolera, M.S.P.; Björk, M.. |
The effect of copper (Cu) on the daily growth rate (DGR) and photosynthetic efficiency (PE) of the brown macroalga Padina boergesenii was studied under controlled laboratory conditions. The DGR was measured as an increase in fresh weight while the PE was measured as the ratio of variable to maximal chlorophyll fluorescence (Fv/Fm). Padina boegesenii were exposed to 25, 50, 100 and 500mg Cu/l for 21 days. The DGR and PE of P. boergesenii decreased significantly with an increase in copper concentration in the growth media. This study shows that copper is acutely toxic to P. boergesenii at concentrations higher than 500mg Cu/l. Low concentration of copper is toxic to P. boergesenii after a prolonged exposure of 21 days. Similarly, exposure time has a... |
Tipo: Proceedings Paper |
Palavras-chave: Copper; Algae. |
Ano: 1999 |
URL: http://hdl.handle.net/1834/787 |
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Vranken, G.; Heip, C.H.R.. |
Toxicity of copper, lead and mercury to the nematode <i>Diplolaimella</i> spec 1 is studied. Mortality responses obtained demonstrate high resistance to heavy metals. Population growth parameters as the intrinsic rate of natural increase and net-reproductivity are significantly depressed at copper-concentrations which cause no juvenile mortality. The lowest concentrations tested caused significant inhibition of development rate in both sexes. For this particular nematode species suppression of fecundity and developmental inhibition are more reliable criteria, determining non-exceedable limits with regard to environmental safety. Our tests show that nematode productivity may be significantly depressed at copper levels found in some areas of the... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Copper; Lead; Mercury; Toxicity; Nematoda [Nematodes]. |
Ano: 1986 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3250 |
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Marchi,Giuliano; Guelfi-Silva,Douglas Ramos; Malaquias,Juaci Vitória; Guilherme,Luiz Roberto Guimarães; Spehar,Carlos Roberto; Martins,Eder de Souza. |
Abstract: The objective of this work was to evaluate the solubility of the micronutrients copper, nickel, and zinc, chemically extracted from silicate agrominerals, as alternative sources of potassium for lettuce (Lactuca sativa) and rice (Oryza sativa) cultures, as well as their availability to the plants. The micronutrient contents of five agrominerals (alkaline ultramafic, biotite schist, volcanic breccia, phlogopite schist, and mining by-product from Chapada) were evaluated, after being extracted by the citric acid, hydrochloric acid, diethylenetriaminepentaacetic acid, 3051A, neutral ammonium citrate, and Mehlich-3 methods. The agrominerals, at the doses of 0 (control), 200, 400, and 600 kg ha-1 K, were mixed to soil where lettuce and rice were... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Copper; Mining by-product; Nickel; Nutrient availability; Zinc. |
Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2020000100600 |
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Lofgren, Hans; Robinson, Sherman; Thurlow, James. |
Zambia's strong dependence on copper exports has suppressed other tradables sectors, indicative of a Dutch disease phenomenon. The current copper crisis will have strong economic effects, possibly reversing such Dutch disease effects. We use a computable general equilibrium model built around a 1995 social accounting matrix to simulate the short- and long-run effects of two scenarios that reflect the current crisis, a 20 percent reduction in world copper prices and a complete collapse of copper mining. Compared to the short run, the long run is characterized by more flexibility in production technology and capital allocation. Both scenarios require a significant reduction in the "non-copper" trade deficit, absorption, and household consumption. The... |
Tipo: Conference Paper or Presentation |
Palavras-chave: Zambia; Copper; Structural adjustment; Agriculture; General equilibrium; International Development; C68; O55; Q17; Q32. |
Ano: 2003 |
URL: http://purl.umn.edu/25805 |
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Yang,Z; Qi,XM; Yang,HM; Dai,H; Xu,CX; Wang,ZY. |
ABSTRACT A dose-response experiment with four dietary copper concentrations (4.17, 8.17, 12.17 and 16.17 mg/kg) was conducted to estimate the growth performance, slaughter performance, nutrient content of fecal and liver copper concentrations of growing Goslings from 28 to 70 d of age. Two hundred healthy male Yangzhou geese with similar body weight were randomized to four groups with five replicates per treatment and ten geese per replicate. Average daily feed intake, average daily gain and feed conversion ratio of geese for each pen were measured from 28 to 70 d of age. At 70 d of age, two geese were selected randomly from each pen and slaughtered to evaluate carcass quality. Metabolism experiment was conducted with five male geese from each group (one... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Goslings; Copper; Growth performance; Slaughter performance; Nutrient content of fecal.. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-635X2018000100045 |
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Sarto,Marcos Vinicius Mansano; Steiner,Fábio; Lana,Maria do Carmo. |
In Brazil, plant-available micronutrients in the soil can be determined by several chemical extractants, the most common of which are dilute acid and chelating solutions. The purpose of this study was to assess the extractants 0.1 mol L-1 HCl, Mehlich-1, Mehlich-3 and DTPA for analysis of the micronutrients Cu, Zn, Fe, and Mn in soils from the state of Paraná. In samples from 12 soils (0-20 cm layer), wheat was planted (Triticum aestivum), grown for 42 days after emergence, and then bean (Phaseolus vulgaris) for 38 days. At the end of each planting period, the soil was sampled again. All extractants tested to assess the availability of Cu, Zn, Fe, and Mn correlated with each other. The efficiency of the extractants HCl, Mehlich-3 and DTPA in assessing... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Soil analysis; Correlation; Copper; Zinc; Iron; Manganese. |
Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832011000600024 |
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Deliberalli,Wanessa; Cansian,Rogério L.; Pereira,Albanin A. M.; Loureiro,Rafael C.; Hepp,Luiz U.; Restello,Rozane M.. |
ABSTRACT Streams in urban areas are strongly impacted by the input of organic matter and metals, for instance copper (Cu) and zinc (Zn). These metals are essential for the aquatic biota, but when absorbed in excess they are toxic. In Chiro nomidae larvae, the deleterious effects of heavy metals can be ascertained by analyzing the morphological deformities of the larval mentum, a structure of the oral cavity. In this study, we evaluated I) the bioavailability of Cu and Zn in urban stream sediments and II) the relationship between Cu and Zn concentrations and the incidence of deformities in the mentum of Chironomus larvae. Chironomid flies were collected from four locations in two streams at an urban area in southern Brazil. They were identified and the... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Biomonitoring; Copper; Environmental quality; Mentum; Zinc. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702018000100316 |
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Brainer,Mônica Maria de Almeida; Menten,José Fernando Machado; Vale,Marcos Martinez do; Morais,Sônia Cristina Daroz de. |
Feeding cupric citrate as alternative to cupric sulfate to broilers has been suggested in the literature. Day-old male broiler chicks (1,200) were used in an experiment to evaluate the efficacy of cupric citrate supplementation (75 mg Cu kg-1) during the 1-21, 22-42 or 1-42 d periods in comparison to an unsupplemented diet and a diet supplemented with cupric sulfate (200 mg Cu kg-1, 1-42 d). A randomized block design was used, with five treatments, six replicates and 40 birds per pen. The diets, based on corn and soybean meal, and water were offered ad libitum during the 42-day experimental period. Over the entire period, there was no effect of copper supplementation (P > 0.05) on bird live weight, weight gain, feed intake, feed conversion and... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Broiler litter; Poultry; Copper; Performance. |
Ano: 2003 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162003000300004 |
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Valladares,Gustavo Souza; Camargo,Otávio Antônio de; Carvalho,José Ruy Porto de; Silva,Alessandra Maria Cia. |
Agricultural management with chemicals may contaminate the soil with heavy metals. The objective of this study was to apply Principal Component Analysis and geoprocessing techniques to identify the origin of the metals Cu, Fe, Mn, Zn, Ni, Pb, Cr and Cd as potential contaminants of agricultural soils. The study was developed in an area of vineyard cultivation in the State of São Paulo, Brazil. Soil samples were collected and GPS located under different uses and coverings. The metal concentrations in the soils were determined using the DTPA method. The Cu and Zn content was considered high in most of the samples, and was larger in the areas cultivated with vineyards that had been under the application of fungicides for several decades. The concentrations of... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: PCA; GIS; Soil pollution; Copper; Zinc. |
Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162009000300011 |
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Moreira, Silvino Guimarães; Prochnow, Luís Ignácio; Pauletti, Volnei; Silva, Bruno Montoani; Kiehl, Jorge de Castro; Silva, Carine Gregório Machado. |
The effect of liming on the availability of micronutrients to soybean cultivated during different numbers of years under no tillage (NT) was investigated. The treatments consisted of the number of years under NT (three, six, and nine years) and five rates of lime (0, 33, 67 and 100% of the amount calculated to raise soil base saturation to 70%) broadcast on soil surface plus the rate of 100% broadcast with incorporation in the 0-0.20 m layer of a clayey Red Oxisol. Soil and leaf samples were collected at two vegetative stages of the crop (vegetative V4 and blossoming R2). The soil was sampled at depths of 0-0.05, 0.05-0.10, 0.10-0.20, and 0.20-0.30 m. Surface liming had little effect on extractable soil micronutrient and nutrient concentrations in soybean... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Copper; Iron; Manganese; Zinc; No till Fertilidade do solo. |
Ano: 2017 |
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/30691 |
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Registros recuperados: 61 | |
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