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991.
Rosário Gonçalves Isabel Mariano Alejandro Núñez Sandra Branco Graham Fairfoul Robin Nicholas 《Veterinary journal (London, England : 1997)》2010,183(2):219-221
An outbreak of severe respiratory disease in a goat herd was associated with Mycoplasma ovipneumoniae, Mycoplasma arginini, Mannheimia haemolytica and Pasteurella multocida with mortality rates exceeding 20% in kids. Post mortem features in affected kids included severe pleuropneumonia, lung consolidation, large quantities of pleural fluid and pericarditis. This is the first report of atypical proliferative pneumonia in goats in Portugal. 相似文献
992.
Rosolen SG Lamory B Harms F Sahel JA Picaud S LeGargasson JF 《Veterinary ophthalmology》2010,13(6):369-376
Purpose To perform cellular‐level in vivo imaging of the feline retina using an adaptive optics flood illumination fundus camera (AO FIFC) designed for the human eye. Materials and methods Cellular‐level images were obtained from three eyes of two normal sedated cats. Ocular aberrations were corrected using an AO system based on a 52‐acuator electromagnetic deformable mirror and a 1024 lenslet Hartmann–Shack sensor (both Imagine Eyes, Orsay, France). A square 3°×3° area of the ocular fundus was flood‐illuminated by a pulsed LED emitting at 850 nm and imaged onto a low‐noise, high‐resolution CCD camera. The animal’s pupils were dilated and the effective pupil size was set to 7.5 mm. Conjunctival atraumatic clips were used to avoid eyeball movements and eyelid closure. The cornea was artificially hydrated throughout the experiments. Each acquisition consisted of 20 consecutive images, out of which 10 were numerically averaged to produce an enhanced final image. Results The total amount of ocular aberrations was greatly reduced by the AO correction, from 2.4 to 0.21 microns root mean square on average. The resulting images presented white dots distributed at a density similar to that of cone photoreceptors and they allowed us to visualize small blood vessels and nerve fiber bundles at a higher resolution than classically obtained with conventional fundus photography. Conclusion Retinal imaging with cellular resolution was feasible in cats under sedation using an AO FIFC designed for human eyes without any optical modification. The AO FIFC technology could find new applications in clinical, pharmacological, and toxicological investigations. 相似文献
993.
Crop growth analysis and modeling based on a slightly modified version of the LINTUL model was used for the assessment of the effect of genetic diversity, as expressed by differences in characteristics such as ploidy, parentage and other specific traits, on the growth and yield responses of Andean potatoes to agroecological conditions in Bolivia. The aim of the present study was to conduct a comparative growth analysis of nine genotypes to describe their performance under the prevalent conditions in the high Andes. We also simulated the performance of nine genotypes from the species Solanum tuberosum subspecies andigenum and tuberosum, Solanumajanhuiri, and their hybrids as affected by frost. The simulations were run using a user-friendly simulation model based on the LINTUL framework. 相似文献
994.
Eva Pinho Mariana Henriques Rosário Oliveira Alberto Dias Graça Soares 《Fibers and Polymers》2010,11(2):271-276
The goal of this work was to create a new generation of greener fabrics made of natural materials. For that, resveratrol (Res),
obtained from Polygonum cuspidatum extract and known to have antibacterial, antifungal, and anti-inflammatory activity, was applied by an exhaustion method
to cotton, bamboo, and silk knit fabrics. The fabrics adsorption behavior was tested and the amount of Res adsorbed was determined
by its decrease on the immersion solutions with time and measured by spectrophotometry at 350 nm. The maximum adsorption capacity
was observed for silk and it was independent of pH conditions used (50.5 % at pH=7 and 58.3 % at pH=5 of the initial Res concentration).
At acidic pH conditions, cotton adsorbed 51.2 % of Res and Bamboo adsorbed only 28.1 % in 15 min. However, neither cotton
nor bamboo adsorbed Res at pH=7. The release behavior was also analyzed and the highest Res release was observed for cotton
in alkaline sweat and urine mimic solutions. The lowest release was achieved by cotton in water (1.0 ng/ml). Moreover, no relation was found between the amounts of Res adsorbed or released and cell viability. In conclusion, this
work shows that it is possible to obtain cotton, bamboo, and silk functionalized with resveratrol. The incorporating process
here described is simple and silk-Res can be presented as a good combination. 相似文献
995.
996.
997.
A Chiamenti CR Aguiar Filho LM Freitas Neto RM Chaves FF Paula‐Lopes PF Lima PBD Gonçalves MAL Oliveira 《Reproduction in domestic animals》2010,45(5):e68-e72
The objective of this study was to evaluate the effect of retinol (RT) and retinoic acid (RA) on the in vitro development of pre‐implantation goat embryos cultured in potassium simplex optimized medium or synthetic oviduct fluid or cocultured in oviductal cells monolayer either in potassium simplex optimized medium or synthetic oviduct fluid. A total of 2407 cumulus‐oocyte complexes were aspirated from 2 to 6 mm ovarian follicles from slaughtered animals. Selected cumulus‐oocyte complexes were subjected to in vitro maturation in TCM 199 for 24 h at 39°C in an atmosphere of 5% (v/v) CO2 in humidified air. In vitro fertilization was performed in modified defined medium. Eighteen hours after in vitro fertilization, cumulus cells were removed and presumptive zygotes were randomly distributed into experimental groups. In Experiment 1, presumptive zygotes were cultured in potassium simplex optimized medium, potassium simplex optimized medium + RT, potassium simplex optimized medium + retinoic acid, synthetic oviduct fluid, synthetic oviduct fluid + RT and synthetic oviduct fluid + RA at 39°C in a humidified atmosphere of 5% (v/v) CO2, 5% (v/v) O2 and 90% (v/v) N2. In Experiment 2, presumptive zygotes were cocultured in potassium simplex optimized medium + oviductal cells monolayer, potassium simplex optimized medium + RT + oviductal cells monolayer, potassium simplex optimized medium + RA + oviductal cells monolayer, synthetic oviduct fluid + oviductal cells monolayer, synthetic oviduct fluid + RT + oviductal cells monolayer and synthetic oviduct fluid + RA + oviductal cells monolayer in an atmosphere of 5% (v/v) CO2 in humidified air. In both experiments, media were partially changed on day 2 after in vitro fertilization and unfertilized oocytes were excluded from the experiment. Embryos were cultured or cocultured for 8 days. In Experiment 1, there was no effect of RT or RA supplementation on the proportion of oocytes that reached the morula or blastocyst stages. By contrast, Experiment 2 demonstrated that the addition of 0.28 μg/ml RT and 0.5 μm RA to the embryo culture media stimulated (p < 0.05) development to the morula and blastocyst stages under the coculture conditions tested. In conclusion, retinoids play an important role in pre‐implantation development of goat embryos and can be used to enhance in vitro embryo production. 相似文献
998.
A neural network experiment on the site-specific simulation of potato tuber growth in Eastern Canada
Jérôme G. Fortin François Anctil Martin A. Bolinder 《Computers and Electronics in Agriculture》2010,73(2):126-449
The objective of this work was to optimize a neural network (NN) for modelling potato tuber growth and its in-field variations in eastern Canada. In addition to climatic inputs, the cumulative and maximal leaf area index (LAI) were incorporated to account for in-field scale variability. Soil and genetic parameters were assumed to be integrated in LAI as suggested by earlier work. Each input and combination of inputs was evaluated from the changes they induced in MAE (mean absolute error) and RMSE (root mean square error). Results using data from several replicated on-farm experiments between 2005 and 2008 suggest that a NN model using cumulative solar radiation, cumulative rainfall and cumulative LAI can adequately model site-specific tuber growth. The MAE of the retained model was 209 kg DM ha−1, which represents less than 4% of the mean final tuber yield for the 3 years of the study. Non-linear effects of explicative variables on tuber yield were attested by comparing the results of the NN simulations to those of a multiple linear regression (MLR). The failure of MLR to simulate temporal discontinuities in tuber growth supports the use of a non-linear approach such as a NN to model tuber growth. 相似文献
999.
Maria Ivanilda de Aguiar Stoécio Malta Ferreira Maia Francisco Alisson da Silva Xavier Eduardo de Sá Mendonça João Ambrósio Araújo Filho Teógenes Senna de Oliveira 《Agroforestry Systems》2010,79(3):277-289
Inadequate soil management practices adopted in the Brazilian semi-arid region contribute to erosive processes. Agroforestry
systems (AFs) have been considered an alternative to reduce water erosion. This study aimed to evaluate the impact of two
alternatives AFs, a traditional and an intensive cropping system on the losses of sediments, water, organic carbon and nutrients
caused by water erosion in comparison to the natural vegetation (caatinga) in a semi-arid region of northeastern Brazil. The
agroecosystems studied were: agrosilvopasture (AGP) which consisted of an alley cropping system, cultivated with Leucaena leucocephala and maize, within an area composed by 22% of native trees (200 native trees per hectare) which was grazed during the dry
season; silvopasture (SILV) that was composed by 38% of native trees (260 trees per hectare) with a stocking rate of 20 ewes
during whole year; traditional agrosilvopasture (TRAG) being managed as following: total deforestation, burning of the residues,
cropped with maize for 2 years (1998 and 1999) and fallow during 8–10 years; and intensive cropping (IC) system which was
deforested and burned in 1997 followed by cultivation of maize from 1998 to 2002, and thereafter by a fallow period of 8–10 years
similar to TRAG. Two areas of native forest (NF1, NF2) known as ‘caatinga’, used as grassland during the dry season and as
a source of wood, were selected and used as reference of steady state in the comparative study in relation to the cultivated
sites. Sediment and water losses as a result of erosion were collected during two rainy seasons, i.e. 2003 and 2004, and nutrients
and organic carbon contents were determined. Soil samples were collected and organic carbon, pH in water, pH in KCl, water
dispersible clay (WDC) and hydraulic conductivity (K0) were measured. In 2003, sediment and water losses did not differ significantly among all treatments. However, in 2004, TRAG
(0.70 Mg ha−1) and NF1 (1.37 Mg ha−1) showed the highest sediment losses, whereas TRAG and IC presented the highest water losses. On average, nutrients losses
in cropped areas were lower than in natural vegetation (NF1, NF2). The alternative AFs (AGP, SILV) were efficient to reduce
water erosion effects when compared to the most common agricultural practices adopted in the region, being highly recommended
as sustainable technical alternatives for food production in the region. 相似文献
1000.
Simon Egli François Ayer Martina Peter Britta Eilmann Andreas Rigling 《Annals of Forest Science》2010,67(5):509-509