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591.
John G. Brayan Paul R. Haddad Gerald J. Sharp Sergio Dilli James M. Desmarchelier 《Pest management science》1992,34(3):215-219
Carbaryl was extracted from aged samples of rice, maize, peas and sunflower seeds using hexane, acetone and methanol. The quantities of insecticide extracted from the grain by acetone and methanol were much higher than that extracted by hexane for all four products. Methanol extracted higher levels of carbaryl than acetone from maize and peas but for rice and sunflower seeds the results were similar for the two solvents. Extraction by simply standing the whole grain in solvent for 48 h generally resulted in similar extracted levels of carbaryl to those obtained using more exhaustive techniques, such as grinding the grain or Soxhlet extraction. However, grinding or Soxhlet extraction removed the pesticide from the grain more rapidly. 相似文献
592.
Canobbio Sergio Mezzanotte Valeria Sanfilippo Umberto Benvenuto Federica 《Water, air, and soil pollution》2009,203(1-4):359-368
Water, Air, & Soil Pollution - Mobilization of arsenic (As) in the subsurface environment can result in elevated concentrations of As in groundwater and potential human exposure and adverse... 相似文献
593.
594.
In fruit trees, understanding genetic determinisms of architectural traits is considered as a promising manner to control
vegetative development and yield regularity. In this context, our study aimed to classify 2-year-old apple hybrids on the
basis of their architectural traits. From a fine phenotyping, trees were described as tree graphs, including topological and
geometric information. To evaluate the similarity between trees, comparison methods based on edit operations (substitution,
insertion and deletion) were carried out. Distance between two tree graphs was computed by minimising the sum of the costs
of the edit operations applied to transform one tree into another. Two algorithms for the comparison of unordered and partially
ordered tree graphs were applied to a sub-sample of the population, taking into account several geometric attributes. For
each comparison, a dissimilarity matrix was computed, and subsequently trees were clustered. A local interpretation of the
matched entities was proposed through schematic representations of the trees, and similarities between trees were analysed
within and between clusters. The tree graphs, both unordered or partially ordered and whether the attributes were considered
or not, were grouped, by clustering, according to the number of entities per tree. The robustness of the unordered comparison
was demonstrated by its application to the whole population, since it provided results similar to those obtained on the sub-sample.
Further developments towards a higher relative weight of geometric versus topological information are discussed in the perspective
to define an architectural ideotype in apple. 相似文献
595.
Campos Isidro González-Gómez Laura Villodre Julio Calera Maria Campoy Jaime Jiménez Nuria Plaza Carmen Sánchez-Prieto Sergio Calera Alfonso 《Precision Agriculture》2019,20(2):214-236
Precision Agriculture - This paper explored the ability of remote sensing (RS) and meteorological data to map the variability of yield/biomass in cultivated wheat (Triticum aestivum). The... 相似文献
596.
Alfonso Llanderal Pedro García-Caparrós María L. Segura Juana I. Contreras 《Journal of plant nutrition》2019,42(10):1205-1217
The aims of this trial were to determine the spatial and temporal variability of the nutrients in petiole sap in a tomato crop under greenhouse and to determine the number of sub-samples for a representative sample. The experiment consisted of the selection of 20 sampling points. Petiole of fully expanded leaf was collected weekly in order to determine Cl, NO3-N, H2PO4-P, SO4-S, Na, K, Ca and Mg concentrations. Our results showed that variations of NO3-N, Na, Ca and K concentrations in sap were affected by the spatial distribution, whereas SO4-S and Mg concentrations in sap were affected by their temporal distribution. The spatial variability of our experiment could be related to radiation, yield and antagonism between nutrients, whereas the time variability could be related to the phenological stage of the plant and the antagonism between nutrients. The suggested number of petiole sub-sample ranging from 25 to 113 depending on nutrient. 相似文献
597.
Cristina Cabaleiro Carolina Couceiro Sonia Pereira Miguel Cid Martín Barrasa Antonio Segura 《European journal of plant pathology / European Foundation for Plant Pathology》2008,121(2):121-130
Several vineyards in Rías Baixas and one in the Ribeira Sacra (Spain) were monitored and the spatial pattern of leafroll-diseased grapevine was analysed at several dates. Unidimensional aggregation analysis (ordinary runs), bidimensional analysis, and disease gradients analysis were used as methods of study of spatial aspects of epidemics of GLRaV. At very low insect populations the mealybug Planococcus citri transmitted the GLRaV-3 from infected plants to healthy ones planted between them in an experimental plot at Beluso; an initial focus of leafroll-infected grapevines was detected 2 years after planting at the area where the vectors had been located infesting the old plants. Within 8 years some new foci appeared and coalesced, and the incidence reached >80%. In three commercial plots where no vectors were observed, the spatial analysis of the diseased plants showed three different situations. In Meaño, the study of the evolution of the spatial patterns of diseased plants between 1992 and 2005 suggested slow vectorial field transmission of GLRaV-3. In Goián the analysis for only 2 years suggested random distribution; therefore the viruses were arriving with the planting material, but the runs analysis of some lines suggested incipient spread of GLRaV-3. In Portomarín the incidence of both GLRaV-2 and 3 was low and their distribution was random, without any evidence of field spread. These examples of the study of the spatial analysis of leafroll-infected plants may be helpful to determine whether or not spread of the viruses is occurring, and the best control measures to take. 相似文献
598.
Mirjam A.F. Ros-Tonen Tinde van Andel Carla Morsello Kei Otsuki Sergio Rosendo Imme Scholz 《Forest Ecology and Management》2008
There is more to sustainable forest management than reduced impact logging. Partnerships between multiple actors are needed in order to create the institutional context for good forest governance and sustainable forest management and stimulate the necessary local community involvement. The idea behind this is that the parties would be able to achieve more jointly than on their own by combining assets, knowledge, skills and political power of actors at different levels of scale. This article aims to demonstrate by example the nature and variety of forest-related partnerships in Brazilian Amazonia. Based on the lessons learned from these cases and the authors’ experience, the principal characteristics of successful partnerships are described, with a focus on political and socioeconomic aspects. These characteristics include fairly negotiated partnership objectives, the active involvement of the public sector as well as impartial brokers, equitable and cost-effective institutional arrangements, sufficient and equitably shared benefits for all the parties involved, addressing socioeconomic drawbacks, and taking measures to maintain sustainable exploitation levels. The authors argue that, in addition to product-oriented partnerships which focus on sustainable forest management, there is also a need for politically oriented partnerships based on civil society coalitions. The watchdog function of these politically oriented partnerships, their awareness-raising campaigns regarding detrimental policies and practices, and advocacy for good forest governance are essential for the creation of the appropriate legal and political framework for sustainable forest management. 相似文献
599.
Herlinde Dumez Enrique Gallardo Stephane Culine Joan Carles Galceran Patrick Sch?ffski Jean P. Droz Sonia Extremera Sergio Szyldergemajn Aude Fléchon 《Marine drugs》2009,7(3):451-463
The objective of this exploratory, open-label, single-arm, phase II clinical trial was to evaluate plitidepsin (5 mg/m2) administered as a 3-hour continuous intravenous infusion every two weeks to patients with locally advanced/metastatic transitional cell carcinoma of the urothelium who relapsed/progressed after first-line chemotherapy. Treatment cycles were repeated for up to 12 cycles or until disease progression, unacceptable toxicity, patient refusal or treatment delay for >2 weeks. The primary efficacy endpoint was objective response rate according to RECIST. Secondary endpoints were the rate of SD lasting ≥ 6 months and time-to-event variables. Toxicity was assessed using NCI-CTC v. 3.0. Twenty-one patients received 57 treatment cycles. No objective tumor responses occurred. SD lasting <6 months was observed in two of 18 evaluable patients. With a median follow-up of 4.6 months, the median PFR and the median OS were 1.4 months and 2.3 months, respectively. The most common AEs were mild to moderate nausea, fatigue, myalgia and anorexia. Anemia, lymphopenia, and increases in transaminases, alkaline phosphatase and creatinine were the most frequent laboratory abnormalities. No severe neutropenia occurred. Treatment was feasible and generally well tolerated in this patient population; however the lack of antitumor activity precludes further studies of plitidepsin in this setting. 相似文献
600.
Maria A. Arribére Linda M. Campbell Andrea P. Rizzo Marina Arcagni Jorge Revenga Sergio Ribeiro Guevara 《Water, air, and soil pollution》2010,212(1-4):167-182
The Northern Patagonian Andean range shared by Chile and Argentina has numerous glacial oligotrophic lakes protected in a series of National Parks. Recent baseline surveys indicated that concentrations in muscle and liver tissues from various fish species from across Nahuel Huapi and Los Alerces National Parks in Argentina were comparable or higher than similar fish species from other parts of the world. As a result, Lake Moreno, in Nahuel Huapi National Park, was chosen to investigate multiple element sinks, trends, and transfer in a representative Patagonia aquatic food web. The metals and metalloids Ag, As, Ba, Br, Cs, Co, Cr, Fe, Hg, K, Na, Rb, Se, and Zn were analyzed in three size plankton fractions, submerged macrophytes, biofilm, insect larvae, amphipods, decapods, gastropods (snails), annelids (earthworms), and forage fish. Except for nanoplankton (10–53 μm; small-celled algae, rotifers) and microplankton (53–200 μm; larger algae, ciliates, zooplankton nauplii), which share elemental compositional similarities, each taxon category had its own distinctive compositional pattern, revealed by principal component analysis. Nano- and microplankton tend to be relatively elevated in some metals, including As, Co, Cr, Fe, Hg, Zn, and Rb, followed by biofilm. Shredder-scrapper Trichoptera (caddisflies) have higher concentration of most of the studied elements than other insect larvae taxa, especially carnivorous Odonata (Anisoptera, dragonflies), which were associated with lower elemental contents. Those trends point to an overall tendency for biodiminishing element concentrations with trophic level in the benthos of Lake Moreno. 相似文献