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1.
Lamastra L Ferrari F Fait G Greco L Kennedy SH Capri E Trevisan M 《Pest management science》2011,67(11):1439-1445
BACKGROUND: 1,3‐Dichloropropene (1,3‐D, CAS No. 542‐75‐6) is a broad‐spectrum soil fumigant used to control numerous species of soilborne plant‐parasitic nematodes. 1,3‐D consists of two isomers, (Z)‐ and (E)‐1,3‐D. There are a number of low‐level chlorinated compounds that could potentially be produced as a part of the 1,3‐D manufacturing process. 1,3‐D and its metabolites, as well as potentially related chlorinated compounds, represent potential groundwater contaminants. RESULTS: This study has investigated the hydrolytic stability, under biotic and abiotic conditions in the laboratory, of an extensive representative list of 1,3‐D and potentially related chlorinated compounds in order to predict their environmental fate. All of these compounds showed intrinsic hydrolytic instability under both abiotic and biotic test conditions. Furthermore, a monitoring programme was carried out. Twenty‐five wells were monitored in five Italian regions characterised by historical and existing use of 1,3‐D. The parent compound, its two major metabolites and potentially related chlorinated compounds were not detected in the well water at > 0.1 µg L?1 at any sampling location. CONCLUSION: The soil fumigant (E,Z)‐1,3‐D, its metabolites and potentially related chlorinated compounds constitute a low risk to groundwater. Copyright © 2011 Society of Chemical Industry 相似文献
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E Capri R Alberici C R Glass G Minuto M Trevisan 《Journal of agricultural and food chemistry》1999,47(10):4443-4449
Recent legislation in the European Union requires regulators of member states to carry out risk assessments using data for actual or potential operator exposure, or estimates of exposure from models. However, the existing models have few datasets from studies carried out on greenhouse or indoor crops, particularly in southern Europe. In this study potential dermal and inhalatory exposures were measured in two trials in Italian greenhouses. The total potential dermal operator exposure of the applicator, measured with a whole-body passive dosimetry method, was 15.4 and 37.1 mL/h of the diluted pesticide mixture. The majority of the contamination was on the hands and on the lower part of the coverall. Approximately 0. 003% of the active ingredient (ai) applied to the crop area contaminated the coverall worn by the operator. The potential dermal exposure during the mixing and loading phase accounted for 6-8% of the total potential dermal exposure during the whole process. Inhalation exposure accounted for only 0.05-0.07% of the total potential operator exposure. Model predictions of the potential operator exposure using a modified version of the German model overestimate the mixing-loading exposure while underestimating the application exposure. These data are evidence that the estimation coefficient set for hand-held application to ornamental and horticultural crops may be inadequate for the agronomic conditions of southern Europe. 相似文献
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A 'step-by-step' method was used to develop a simplified procedure for calculating pesticide residue levels on fruit at harvest by considering the application of the compound and the relevant routes of loss. The model is applicable to cases where the most important exposure route is by direct spray to the canopy of the crop and where uptake into the plant by the roots can be disregarded. The exposure dose is calculated by considering the proportion of total crop cover represented by the fruits. The loss processes considered are photodegradation, uptake, volatilization and washoff.The outputs of the model were compared with measured residues of pesticides on pear. Analysis of the model fit demonstrates that the model predicted the measured data with a good level of accuracy for four of seven investigated pesticides. The predicted/observed quotients are close to 1, as is the modelling efficiency, and there are no great differences between the predicted and observed values. Taking into account the extreme simplicity of the model and the complexity of the environmental processes considered, these results encourage further research into the modelling of residue behaviour in food commodities.The objectives of this work were to produce a tool to predict pesticide residues in products of plant origin, to complement monitoring of pesticide levels and to be useful in evaluating the effect of government policies on food safety. All predicted values were below the maximum levels fixed for pesticide residues in pear, as amended in Council Directives 86/362/EEC and 90/642/EEC. Copyright (c) 2008 Society of Chemical Industry. 相似文献
4.
Soluble carbohydrates content in tomato pollen and its variations along and between blooming periods
The soluble carbohydrates content in the mature (starchless) pollen of the tomato (Solanum lycopersicum L.) cv. Platense was studied at several moments of the blooming period in two consecutive years. The aim of the analysis was to evaluate if the content of soluble carbohydrates is relatively constant or if it can fluctuate along the blooming period. No significant variations in pollen viability were recorded along each season. The soluble carbohydrates found and their concentrations can change significantly among samples, but the fluctuations observed did not follow a strongly definite pattern in any season. Reducing sugars predominated; small quantities of a phosphorylated sugar, UDP-glucose, and maltosaccharides were also recorded. The constant presence of maltosaccharides is a novel record for pollen. Sucrose was absent in one season, but present in the other, in low percentages in contrast to reducing sugars. Changes in the soluble carbohydrates content have been usually related with alterations in pollen fertility. However, there may be some flexibility in the metabolism of the pollen studied this time, at least within a certain range, which may allow constant adjustments to maintain acceptable levels of viability despite the variations in the carbohydrates concentrations. 相似文献
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Zewei?Miao Laura?Padovani Carlo?Riparbelli Amy?M.?Ritter Marco?Trevisan Ettore?CapriEmail author 《Paddy and Water Environment》2003,1(3):121-132
Pesticides are very important in European rice production. For appropriate environmental protection, it is useful to predict the potential impact of pesticides after application, in paddy fields, in paddy runoff, and in the surrounding water, by calculating predicted environmental concentrations (PECs). In this paper, a joint simulation is described, coupling a field-scale pesticide fate model (RICEWQ) and a transportation model (RIVWQ) to evaluate the potential for predicting environmental concentrations of pesticides in the paddy field and adjacent surface water bodies and comparing the predicted values with the monitoring data. The results demonstrate that the application of the calibrated field-scale RICEWQ model is a conservative method to predict the PEC at the watershed level, overestimating the observed data; the coupled RICEWQ and RIVWQ models could be adequately used to predict PECs in the surrounding water at watershed level and in the higher tier risk assessment procedure. 相似文献
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Karpova NN Pickenhagen A Lindholm J Tiraboschi E Kulesskaya N Agústsdóttir A Antila H Popova D Akamine Y Bahi A Sullivan R Hen R Drew LJ Castrén E 《Science (New York, N.Y.)》2011,334(6063):1731-1734
Antidepressant drugs and psychotherapy combined are more effective in treating mood disorders than either treatment alone, but the neurobiological basis of this interaction is unknown. To investigate how antidepressants influence the response of mood-related systems to behavioral experience, we used a fear-conditioning and extinction paradigm in mice. Combining extinction training with chronic fluoxetine, but neither treatment alone, induced an enduring loss of conditioned fear memory in adult animals. Fluoxetine treatment increased synaptic plasticity, converted the fear memory circuitry to a more immature state, and acted through local brain-derived neurotrophic factor. Fluoxetine-induced plasticity may allow fear erasure by extinction-guided remodeling of the memory circuitry. Thus, the pharmacological effects of antidepressants need to be combined with psychological rehabilitation to reorganize networks rendered more plastic by the drug treatment. 相似文献
8.
Antonino Galati Luciano Gristina Maria Crescimanno Ettore Barone Agata Novara 《Land Degradation \u0026amp; Development》2015,26(6):557-564
Evaluating the economic damage caused by soil erosion is important. In addition to increasing the awareness of the problem among farmers and policy makers, evaluation of the economic damage caused by erosion can promote the implementation of more sustainable soil management practices. In the present study, we describe a new approach to evaluate incentives for the adoption of agri‐environment measure (AEM) in degraded and eroded vineyards. To estimate this incentive, the replacement cost (RC) and the loss of income are calculated when the vineyard is managed with conventional tillage versus a cover crop (AEM). Our findings show that the incentive could range from the loss of income due to AEM adoption to the ecosystem service benefit (RCC − RCAEM). In our case study, the incentive ranged from 315 € ha−1 (loss of income) to 1,088 € ha−1 (ecosystem service benefit). Within this range, the incentive amount is determined according to efficiency criteria based on vineyard slope. We also present a conceptual model of public spending efficiency that should help policy makers decide how to allocate the incentives so as to maximize the economic return associated with ecosystem services. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
9.
Luisa Patrolecco Silvio Capri Silvia De Angelis Romano Pagnotta Stefano Polesello Sara Valsecchi 《Water, air, and soil pollution》2006,172(1-4):151-166
Nonylphenol (NP), nonylphenol mono- and di-ethoxylate (NP1EO, NP2EO) and bisphenol A (BPA) were determined in water, suspended particulate matter (s.p.m.) and bed sediment collected from the most polluted stretch of Tiber river (Italy) in the neighbourhood of Rome. Analytes were recovered from water samples by solid-phase extraction (SPE) on Si–C18 cartridges and analysed by HPLC with fluorescence detection. Solid samples were extracted by using an aqueous solution of the non-ionic surfactant Tween 80. Results indicated that 2–42% of NP, 9–45% of NP1EO, 11–18% of NP2EO and 4–62% of BPA respectively occurred in the suspended phase. In general, for all compounds a higher affinity for s.p.m. than for bed sediments was observed, reflecting differences in the nature of particles and in their sorption capacity for organic micro-pollutants. The partition of target compounds in river compartments was affected by differences in hydrological conditions between the two sampling campaigns. Run-off from the basin or resuspension/redissolution from sediments was an important source of nonylphenol and bisphenol A during high discharge regimes. Partition coefficients of compounds (log K oc ) between water and s.p.m. were calculated under stable flow condition. K oc values, experimentally measured in the river, were higher than those predicted by K ow , implying that specific chemical interaction could occur in the sorption mechanisms for these group of compounds. 相似文献
10.
Use of Red Blood Cell Membranes to Evaluate the Antioxidant Potential of Plant Extracts 总被引：1，自引：1，他引：0
Gabriella Cavallini Marina Dachà Lucia Potenza Annamaria Ranieri Claudia Scattino Antonella Castagna Ettore Bergamini 《Plant foods for human nutrition (Dordrecht, Netherlands)》2014,69(2):108-114
Antioxidant phytochemicals in fruits and vegetables of a vegetarian diet may account for the reduced risk of aging and stress oxidative associated diseases. In this study, a simple, rapid and accurate new bioassay for the determination of the antioxidant activity of purified or crude plant extracts and thier interactions is described, based on the fluorimetric determination of thiobarbituric acid reactive substances (TBARS) released by UV-B radiated red blood cell (RBC) ghosts. Pure resveratrol, white and red wine and pomegranate juice (PJ) were used as antioxidant source to test the biological method. TBARS production is a function of radiation time, the number of RBC ghosts in the radiated sample and the loaded antioxidant. The antioxidant activity of resveratrol was detected at a submicromolar concentration range [0.02 μg/mL–0.1 μmol/L]. The activity of red wine was almost 10 times higher than that of white wine, and PJ juice had the highest activity. Submaximal protective effects of PJ and red wine were additive. 相似文献