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101.
BACKGROUND: The red palm weevil, Rhynchophorus ferrugineus (Olivier), is a phytophagous insect that feeds on soft succulent tissues of most palm species and is considered the main palm pest in the Middle East and the Mediterranean Basin. The aim of this study was to test the efficacy of imidacloprid oil dispersion (OD) as a drench in preventive and curative treatments against R. ferrugineus in Phoenix canariensis, Washingtonia robusta, Washingtonia filifera and Trachycarpus fortunei. RESULTS: Levels of infestation were highest in P. canariensis. There was no infestation in W. filifera. Mean efficacies of 100 and 94% were obtained in preventive and curative treatments respectively. High efficacies in preventive treatments (mean 95.4%) lasted for up to 45 days after application. CONCLUSION: The high efficacies and persistence of imidacloprid OD applied as a drench in young palms show the potential of this product for the management of R. ferrugineus. Copyright © 2011 Society of Chemical Industry 相似文献
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A. J. Hernndez M. J. Adarve Alcazar J. Pastor 《Land Degradation \u0026amp; Development》1998,9(1):21-33
Seventy soil samples around and under urban waste landfills in central Spain were studied for 28 physical and chemical properties. In the unaffected surroundings of landfills there is always a higher proportion of coarse and fine gravel. Chlorides, sulphates and nitrates increase noticeably in all the soils affected by landfills as do Na+, B3+ and Zn2+. Multivariate analyses show that higher or lower water retention in the surface layer plays a main role in the organization of both acid and sandier soils as well as of basic soils and those with a higher proportion of silt and clay. Depending on the acidity or basicity, however, the other main factors reveal different hierarchical levels in the soil variables with regard to the organization of these systems. Thus, in acid soils, Zn2+ and B3+ contribute most noticeably to the second hierarchical level in the edaphic organization. In basic soil without gypsum, the second important gradient of variation is the stoniness (gravel)–fine sand (<2 mm fraction) while the importance of the K+, B3+ and SO4= is relegated to the third factor. In the basic soils with gypsum, not only sulphate, but also Na+, Cl− and Zn2+ plays an essential role in the first factor and the coarse surface elements are also important. The principal components analysis made it possible to establish the main factors involved in the degradation caused by leachates from landfills. Consequently, greater attention could be given to these factors with a view to rehabilitation of degraded soils. © 1998 John Wiley & Sons, Ltd. 相似文献
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Añor S Espadaler JM Pastor J Pumarola M 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2000,14(4):418-423
Electrophysiologic assessment of the blink reflex test and the muscle-evoked potentials evoked by stimulation of the facial nerve were performed in 15 healthy adult Beagles before and after supraorbital (trigeminal) and facial anesthetic nerve blocks performed by lidocaine injections. Unilateral electrical stimulation of the supraorbital nerve elicited 2 ipsilateral (R1 and R2) and a contralateral (Rc) reflex muscle potential in orbicularis oculi muscles. Electrical stimulation of the facial nerve elicited 2 muscle potentials (a direct response [D] and a reflex faciofacial response [RF]) in the ipsilateral orbicularis oculi muscle. Anesthetic block of the left supraorbital nerve resulted in bilateral lack of responses upon left supraorbital nerve stimulation, but normal responses in right and left orbicularis oculi muscles upon right supraorbital stimulation. Right facial anesthetic block produced lack of responses in the right orbicularis oculi muscle regardless the side of supraorbital nerve stimulation. Results of this study demonstrate that the blink reflex can be electrically elicited and assessed in dogs. Reference values for the blink reflex responses and for the muscle potentials evoked by direct facial nerve stimulation in dogs are provided. The potential usefulness of the electrically elicited blink reflex test in the diagnosis of peripheral facial and trigeminal dysfunction in dogs was demonstrated. 相似文献
106.
Post-fire resprouting ability of the non-dominant tree and shrub species of the Mediterranean Basin has not yet been experimentally tested, although this group contributes to maintain the richness of Mediterranean plant communities. In this study, we have analyzed the post-fire recovery ability of 15 woody species that occur in relatively low abundance in dry and sub humid Mediterranean areas in NE of Spain. The main goals have been: (i) to determine experimentally the post-fire resprouting ability of these species and (ii) to compare the abundance of these species in areas affected by wildland fires and in unburned areas. We have observed a high resprouting ability after prescribed burning of most species except for Juniperus communis and J. phoenicea which showed a null resprouting. As the species with high resprouting ability showed similar presence in burned and unburned areas, we can conclude that wildfires are not a factor that constrains the presence of these species in Mediterranean woodlands. However, we found a reduction in the abundance of J. communis and J. phoenicea at the regional level after wildland fires. 相似文献
107.
Traditional models of economic decision-making assume that people are self-interested rational maximizers. Empirical research has demonstrated, however, that people will take into account the interests of others and are sensitive to norms of cooperation and fairness. In one of the most robust tests of this finding, the ultimatum game, individuals will reject a proposed division of a monetary windfall, at a cost to themselves, if they perceive it as unfair. Here we show that in an ultimatum game, humans' closest living relatives, chimpanzees (Pan troglodytes), are rational maximizers and are not sensitive to fairness. These results support the hypothesis that other-regarding preferences and aversion to inequitable outcomes, which play key roles in human social organization, distinguish us from our closest living relatives. 相似文献
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109.
Palmero-Iniesta Marina Pino Joan Pesquer Lluís Espelta Josep Maria 《European Journal of Forest Research》2021,140(4):793-805
European Journal of Forest Research - In Europe, forest area is increasing. These recently established forests can be classified into regenerating after disturbances or expanding into agricultural... 相似文献
110.
Neira JI Pazos M Maestre R Torres JL Medina I 《Journal of agricultural and food chemistry》2011,59(10):5684-5691
The influence of galloyl residues on the antioxidant mechanism of polyphenols to prevent hemoglobin-promoted lipid oxidation was investigated by using polyphenolic fractions with different degrees of galloylation: nongalloylated structures from pine bark (IVP), medium-galloylated from grape pomace (IVG), and high-galloylated from witch hazel bark (IVH). Hemoglobin (Hb) from the pelagic fish horse mackerel (Trachurus trachurus) was employed as a Hb standard. In vitro experiments showed an important increase in the deoxygenation and autoxidation of horse mackerel Hb at acidic pH values. All polyphenolic fractions significantly reduced the redox stability of Hb in buffer solutions, showing a greater deoxygenation and methemoglobin (metHb) formation in the presence of IVH, followed in decreasing order by IVG and IVP. However, galloylated polyphenols (IVH and IVG) were efficient to inhibit the oxidation of the oxygenated Hb (OxyHb) and the formation of lipid oxidation products in chilled washed fish muscle. This antioxidant activity of galloylated proanthocyanidins showed a positive relationship with the phenolic concentration. Polyphenols devoid of galloyl groups (IVP) were less active to prevent either Hb oxidation or lipid oxidation in fish muscle. The results draw attention to the potential role of galloyl residues to lessen Hb-catalyzed lipid oxidation in muscle and to maintain Hb in reduced and oxygenated states, which exhibit lower pro-oxidant activity as compared to the metHb and deoxyHb species. 相似文献