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431.
Domenico Rongai Claudio Cerato Luca Lazzeri Sandro Palmieri Giampiero Patalano 《Journal of pest science》2008,81(4):179-185
During laboratory tests, mineral oil in water emulsion (2%), containing Brassicaceae seed meals (2 g l−1), induced total mortality (100%) among adult female California red scales on detached orange fruits, whereas only 47.5% of
insect mortality was observed with the same mineral oil when used alone. These results were partially confirmed by two preliminary
field trials. With the aim of improving biodegradability and the environmental impact of the insecticidal formulation, mineral
oil was replaced by a vegetable oil without observing any significant variation of the product’s efficacy. In addition, a
clear “dose-effect” of meal in mineral and vegetable oil was also demonstrated. The formulation, essentially based on oil,
meals and some minor additives, shows the following advantages: (1) high insecticidal activity against an insect pest difficult
to control such as Aonidiella aurantii (Maskell); (2) simultaneous control of several pathogens seems to be possible; (3) non-appearance of resistance phenomena
in plant pathogens; and finally, (5) absence of phytotoxicity. 相似文献
432.
Claudio Ioriatti Gianfranco Anfora Gino Angeli Stefano Civolani Silvia Schmidt Edison Pasqualini 《Pest management science》2009,65(3):306-312
BACKGROUND: Emamectin benzoate is a novel macrocyclic lactone insecticide derived from naturally occurring avermectin molecules isolated by fermentation from the soil microorganism Streptomyces avermitilis Kim & Goodfellow. The present study aims to evaluate the toxicity of emamectin benzoate to codling moth, Cydia pomonella (L.), and oriental fruit moth, C. molesta (Busck), under laboratory and semi‐field conditions. RESULTS: Dose response bioassays showed that emamectin benzoate had a high level of intrinsic toxicity to early‐stage larvae of both species, and that contact activity might contribute significantly to mortality. In the semi‐field trials, residual toxicity lasted for more than 1 week. Ovicidal activity was recorded only for C. pomonella (approximately 30%), irrespective of the concentrations tested. Field trials confirmed the efficacy of emamectin benzoate on codling moth when applied at 7 day intervals. Fruit damage, both from the first and second generations, was comparable with that on treatment with chlorpyrifos‐ethyl, used as a chemical reference. CONCLUSION: Emamectin benzoate may be considered a valuable tool for the control of codling moth as a component of an IPM programme. Its collective advantages are: high efficacy, lack of cross‐resistance with currently used products, control of secondary pests such as oriental fruit moth and selective toxicity that spares beneficials. Copyright © 2008 Society of Chemical Industry 相似文献
433.
Mattia Cesa Alessandro Bizzotto Claudio Ferraro Flaminio Fumagalli Pier Luigi Nimis 《Water, air, and soil pollution》2010,208(1-4):59-77
The concentration of Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sb, Se, V and Zn was measured in the aquatic bryophyte Rhynchostegium riparioides after a 4-week transplantation at 83 stations in seven main watercourses and three smaller tributaries of the basin of the River Bacchiglione (NE Italy). The study, carried out in 9 months, aimed at establishing a database for statistical analyses to define a novel index of water quality, specifically calibrated for moss bags, and suitable for bio-monitoring purposes where autochthonous bryophytes are not available. The background level was estimated for each element, the ratio between sample and background concentration was adopted as measure of environmental alteration and a five-class interpretation scale was defined. The 73.8% of measured concentrations reflected a condition of naturality, 16.6% suspect of alteration, 7.6% sure alteration, 1.6% severe alteration and <0.5% extreme alteration. The condition of global environmental alteration (all contaminants) at each station was also defined. Forty-four stations presented absence or suspect of alteration, 39 sure alteration for one or more elements. Bivariate and multivariate analyses revealed (1) highly significant correlations (p?<?0.001) between the concentrations of Co–Mn, Sb–Zn, and Fe–V, depending on both natural and human factors, (2) chemical patterns leading to galvanic industries, metallurgy or urban sewages, in some case with a geographical distribution and (3) a gradient of environmental alteration from the Pre-Alps to the lowland. Coloured maps indicate both point sources and widespread environmental alteration, highlighting not only industrial–urban areas but also some apparently undisturbed sites. 相似文献
434.
Patrizia Di Filippo Carmela Riccardi Donatella Pomata Claudio Gariazzo Francesca Buiarelli 《Water, air, and soil pollution》2010,211(1-4):231-250
Polycyclic aromatic hydrocarbons (PAHs); their derivatives nitro, and methyl-PAHs; n-alkanes; and organic acids were investigated in the aerosol samples collected during two field campaigns conducted at three sampling stations in an industrialized city in southern Italy. The main sources affecting the atmosphere and its toxicity were investigated by means of the diagnostic ratios of: specific particulate-phase PAHs, marker compounds among nitro-PAHs, alkanes, and acids, the dominant wind direction, daily and seasonal abundance of carcinogenic organic substances. The potential importance of the non-regulated pollutants to assess the air quality was confirmed; in fact the carcinogenic organic compounds showed to have scarce correlation with particulate matter (PM) concentration. An exceptionally high variability of toxic compounds at a daily scale was due to meteorological condition causing periods of extremely high pollution levels. 相似文献
435.
Erika Cottone Valentina Pomatto Fulvio Cerri Ezio Campantico Ken Mackie Massimiliano Delpero Alda Guastalla Claudio Dati Patrizia Bovolin Maria Fosca Franzoni 《Fish physiology and biochemistry》2013,39(5):1287-1296
Cannabinoids, the bioactive constituents of Cannabis sativa, and endocannabinoids, among which the most important are anandamide and 2-arachidonoylglycerol, control various biological processes by binding to specific G protein-coupled receptors, namely CB1 and CB2 cannabinoid receptors. While a vast amount of information on the mammalian endocannabinoid system does exist, few data have been reported on bony fish. In the goldfish, Carassius auratus, the CB1 receptor has been cloned and its distribution has been analyzed in the retina, brain and gonads, while CB2 had not yet been isolated. In the present paper, we cloned the goldfish CB2 receptor and show that it presents a quite high degree of amino acid identity with zebrafish Danio rerio CB2A and CB2B receptors, while the percentage of identity is lower with the puffer fish Fugu rubripes CB2, as also confirmed by the phylogenetic analysis. The sequence identity becomes much lower when comparing the goldfish and the mammalian CB2 sequences; as for other species, goldfish CB2 and CB1 amino acid sequences share moderate levels of identity. Western-blotting analysis shows the CB2 receptor as two major bands of about 53 and 40 kDa and other faint bands with apparent molecular masses around 70, 57 and 55 kDa. Since the distribution of a receptor could give information on its physiological role, we evaluated and compared CB1 and CB2 mRNA expression in different goldfish organs by means of qReal-Time PCR. Our results show that both CB1 and CB2 receptors are widely expressed in the goldfish, displaying some tissue specificities, thus opening the way for further functional studies on bony fish and other nonmammalian vertebrates. 相似文献
436.
Valentina Sepe Raffaella Ummarino Maria Valeria D��Auria Orazio Taglialatela-Scafati Simona De Marino Claudio D��Amore Barbara Renga Maria Giovanna Chini Giuseppe Bifulco Yoichi Nakao Nobuhiro Fusetani Stefano Fiorucci Angela Zampella 《Marine drugs》2012,10(11):2448-2466
Using theonellasterol as a novel FXR antagonist hit, we prepared a series of semi-synthetic derivatives in order to gain insight into the structural requirements for exhibiting antagonistic activity. These derivatives are characterized by modification at the exocyclic carbon-carbon double bond at C-4 and at the hydroxyl group at C-3 and were prepared from theonellasterol using simple reactions. Pharmacological investigation showed that the introduction of a hydroxyl group at C-4 as well as the oxidation at C-3 with or without concomitant modification at the exomethylene functionality preserve the ability of theonellasterol to inhibit FXR transactivation caused by CDCA. Docking analysis showed that the placement of these molecules in the FXR-LBD is well stabilized when on ring A functional groups, able to form hydrogen bonds and π interactions, are present. 相似文献
437.
GIS‐based ecological risk assessment for contaminated sites by fish farm effluents using a multicriteria weight of evidence approach
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Claudio Silva Eleuterio Yáñez María Laura Martín‐Díaz Tomás Angel DelValls 《Aquaculture Research》2016,47(2):524-539
In this study, an integrative weight of evidence (WOE) tetrad methodology was developed and used to assess environmental quality and ecological risk at contaminated sites by fish farm effluents using spatial modelling tools [geographical information systems (GIS) and fuzzy logic and multicriteria analysis (MCA)], taking into account the results of four lines of evidence (LOE): the physico‐chemical characteristics of water and sediment, acute toxicity bioassays, biomarkers and the in situ alteration of benthic communities. The methodology was tested in the Rio San Pedro salt marsh creek in southwestern Spain. The proposed approach allowed for a quantitative spatial characterization of ecological risk and a better discrimination based on various types of physical, chemical and biological data. The methodology illustrates how GIS spatial models may be used in conjunction with other tools such as fuzzy logic and MCA to assist in decision‐making processes based on multiple environmental quality criteria and lines of evidence, with the transparency, objectivity and synoptic ability required to address environmental management problems in general and the management of contaminated marine areas affected by fish farms in particular. 相似文献
438.
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440.
Chiara Pecorini Davide Sassera Raffaella Rebucci Francesca Saccone Claudio Bandi Antonella Baldi 《Veterinary research communications》2010,34(3):267-276
Lactoferrin (Lf) is a non-haem iron-binding glycoprotein with a molecular weight of about 80 kDa, synthesized by glandular
epithelial cells and stored in the secondary granules of neutrophils. The physiological significance of Lf is related to non-specific
immune defence against pathogens, immunomodulatory activity, iron homeostasis, antioxidant properties and regulation of cell
growth. Lf is a bioactive component of the mammary secretions and its modulatory and defensive functions do affect the newborn
and the mammary gland as well. In this work a bovine mammary epithelial cell line (BME-UV1) was used as an in vitro model
of the bovine mammary epithelium to examine the protective role of exogenous bovine Lf (bLf) against the cytotoxic damage
induced by bacterial lipopolysaccharides (LPS) and the endogenous bLf mRNA expression after LPS exposure. In the in vitro
model used, exogenous bLf exerts a protective effect against endotoxin cytotoxicity, which could be mediated by the LPS-neutralizing
capability of bLf. In addition, in BME-UV1 cells the response to LPS exposure does not involve bLf mRNA expression, suggesting
that this cell line lack of functional LPS-responsive elements. 相似文献