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451.
452.
Muñoz-Arcos Enrique Castillo Alejandra Cuevas-Aedo Alicia Ovando-Fuentealba Luis Taylor Alex Bustamante-Ortega Ramón Blake William H. Bravo-Linares Claudio 《Journal of Soils and Sediments》2021,21(6):2432-2449
Journal of Soils and Sediments - Wildfires can have major impacts on water scarcity and water quality linked to off-site transfer of polluting ash and nutrients. Understanding sediment sources in... 相似文献
453.
Simone Magni Monica Gaetani Lisa Caturegli Claudio Leto Teresa Tuttolomondo Salvatore La Bella 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(8):722-733
Breeding of turf bermudagrass (Cynodon (L.) Rich.) has made available a broad range of turf varieties with unique morphological and growth traits. Rapid establishment is necessary in order to provide the performance of a mature turf cover in the shortest time possible. The aims of the research were: (1) to determine variation of growth, morphological and biomass traits in bermudagrass accessions belonging to different phenotypic groups during establishment and (2) to relate such variations to establishment speed in order to assess whether contrasting phenotypic traits could induce different establishment patterns in bermudagrass or if a general establishment predictor can be identified for cultivars and ecotypes belonging to the same taxon. Plant material included 44 accessions of bermudagrasses that were grouped in ‘Wild’, ‘Improved’ ‘Hybrid’ and ‘Dwarf types’. Single spaced plants were transplanted in field plots in two locations in Italy (Pisa and Palermo) and allowed to establish without mowing. The following traits were determined: stolon growth rate, internode length, internode diameter and internode volume, phytomer dry weight, leaf width, colour, seed head production, above ground dry biomass, shoot density, horizontal stem density and node density. Establishment speed of accessions was also determined. Stolon growth rate was found to be the only parameter strongly correlated to establishment speed across all entries and for each of the phenotypic groups. Based on these results, stolon growth rate could be assumed as a good predictor of establishment speed for cultivars and ecotypes belonging to the Cynodon genus. 相似文献
454.
Lamagna B Peruccio C Guardascione A Paciello O Costagliola A Giudice C Rondena M Saccone M Uccello V Lamagna F 《Veterinary ophthalmology》2012,15(3):194-199
Two 5-month-old golden retriever dogs were referred for the evaluation of a mass arising from the left ventrolateral conjunctiva of the lower eyelid. The masses were externally located, deemed to be cystic in nature, and were surgically removed, and in one case, 0.15 mL of clear fluid was collected. Cytological examination of the aspirated fluid revealed proteinaceous, basophilic amorphous material, and few epithelial cells with foamy cytoplasm and small nuclei. No micro-organisms were detected. Histological examination of the cysts showed a wall composed of single to double cell layers. The cells were cuboidal to flattened, nonciliated, lined with mild submucosal connective tissues and slight inflammation composed of lymphocytes, plasma cells, and rare macrophages. In some areas, lobules of acinar glandular tissue were observed. To the authors' knowledge, this is the first case report of conjunctival dacryops in dogs. The complete surgical removal of the cysts was curative in both cases. 相似文献
455.
Lucia Canals Daniela Figueroa Hugo Torres-Contreras Claudio Veloso Mauricio Canals 《Journal of Exotic Pet Medicine》2012,21(3):203-206
This article describes the basic prey requirements of Paraphysa sp., a small mygalomorph spider from the central Andes. Paraphysa sp. can be maintained in captivity using mealworms (Tenebrio molitor) as its primary food source. During a period of 66 days the prey requirements (larvae/day) were calculated for weight maintenance and compared with findings of previously reported resting and active metabolic rates. The spiders in this study ate at frequencies between 0.18 and 0.59 larvae/day, with an average of 0.43 ± 0.14 larvae/day. From the regression line between frequency of feeding (larvae/day) and weight gain, we determined that 0.31 larvae/day were needed for a weight gain of 0. Thus, for the spiders to increase their weight, they would need to eat more than 1 larva every 3 days. This frequency yields a caloric intake of 0.193 kcal/d, or equivalently, a carbon dioxide production of 0.189 mL CO2/g·h. The findings in this report are greater than the resting metabolic rate at 35°C, and they agree with the active metabolic requirements of this spider in the field. 相似文献
456.
457.
Paim CB Paim FC Da Silva AS França RT Costa MM Leal CA Soares JF Labruna MB Schetinger MR Mazzanti A Mazzanti CM Monteiro SG Lopes ST 《Veterinary parasitology》2012,185(2-4):131-137
The aim of this study was to evaluate the platelet count, coagulation time and platelet activity in dogs experimentally infected with Rangelia vitalii during the acute phase of the disease. For this study, 12 young dogs (females) were used, separated in two groups. Group A (uninfected control) was composed by healthy dogs (n=5), and group B consisted of R. vitalii-infected animals (n=7). After being inoculated with R. vitalii-infected blood, animals were monitored by blood smear examinations, which showed intra-erythrocytic forms of the parasite five days post-inoculation (PI). Blood samples were collected on days 0, 10, 20 and 30 PI. The material collected was placed in tubes containing EDTA for quantification of platelets, citrate anticoagulant platelet aggregation, and measuring the clotting time. Right after blood collection on days 10 and 20 PI, dogs were anesthetized for collecting bone marrow samples. A significant reduction (P<0.01) of the number of platelets was observed in R. vitalii-infected blood, when compared with uninfected dogs on days 10 and 20 PI. Additionally, macro-platelets were observed only in infected dogs. Prothrombin time and activated partial thromboplastin time did not differ between infected and uninfected dogs. The megakaryocyte count increased (P<0.01) significantly in infected dogs when compared with uninfected ones on days 10 and 20 PI. Platelet aggregation decreased (P<0.01) significantly in infected dogs in comparison to the control on days 10 and 20 PI. Therefore, rangeliosis in dogs causes a severe thrombocytopenia during the acute phase of infection. This platelets reduction probably occurred due to splenic sequestration and/or immune-mediated thrombocytopenia. 相似文献
458.
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
459.
Lezama-Dávila CM Isaac-Márquez AP Zamora-Crescencio P Uc-Encalada Mdel R Justiniano-Apolinar SY del Angel-Robles L Satoskar A Hernández-Rivero L 《Fitoterapia》2007,78(3):255-257
Extracts of the root of Pentalinon andrieuxii, vernacular name of "contrahierva" (solen ak' in Mayan language, were investigated for their lethal effect on the protozoa Leishmania mexicana. The hexanes extract was highly effective to delay and eventually stop parasite survival. 相似文献
460.
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