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551.
E. Montoneri G. Modica C. Bowen D. Gauthier R. Renaud 《International Journal of Hydrogen Energy》1987,12(12):831-835
The electrical resistance of asbestos composite separators stabilized with high concentration ( 40% w/w) of polyphenylene sulfide in 100°C, 30–50 %w/w KOH strongly depends on the initial porosity of the asbestos support. The separators with 0.36 V/w water sorption capacity have 0.20–0.35 Ω. cm2 ohmic drop according to expectations derived from a previous material study. The mechanical strength appears to be related to the separator thickness. 相似文献
552.
D.L. Renaud D.F. Kelton S.J. LeBlanc D.B. Haley T.F. Duffield 《Journal of dairy science》2018,101(2):1785-1794
The objective of this cross-sectional herd-level study was to assess the association of calf management practices on source dairy farms with mortality risk on veal farms. From April to October 2016, 52 source dairy farms supplying male calves to 2 veal operations were visited once. A questionnaire was administered that covered all areas of calf management, calves between 1 and 10 d of age were examined using a standardized health scoring system, and blood was taken to evaluate passive transfer of immunoglobulins. The mortality risk for calves from each dairy farm was calculated based on the number of male calves sold from the dairy farm and that died during 2016 at the veal operations. The mean mortality risk was calculated for both veal farms and, based on the veal facility-adjusted mortality risk, dairy farms were classified as high- or low-mortality source farms. Using the information gathered at the 52 source dairy farms, a logistic regression model was used to assess factors associated with being a high-mortality source farm. Suppliers to veal farm 1 had a mean mortality risk of 9.6% and suppliers to veal farm 2 had a mean mortality risk of 4.2%. The lower mortality risk at veal farm 2 was partially influenced by a shorter period of observation. Of the 182 calves examined during the single visit to the source dairy farms, 41% of male calves and 29% of female calves had at least one identifiable health abnormality. The risk of failure of passive transfer on source dairy farms was low, with only 13% of calves tested having <10 mg of IgG/mL of serum. The subset of calves examined at the source dairy farm was not followed prospectively to the veal farms. Using a tube feeder or pail to feed colostrum, bedding male calves on wood shavings or chopped straw at the source dairy farm, and the herd veterinarian not routinely and actively inquiring about the health and performance of calves during regular herd visits were significantly associated with the farm being classified as a high-mortality source dairy farm. Checking the calving pen at an interval of every 3 h or more during the day was associated with a lower probability of being classified as a high-mortality source dairy farm. The results of this study suggest that there are management practices on the source farm that contribute to the risk of mortality on veal farms. 相似文献
553.
Marthe Malcange Maria-Dolores Prez-Garcia Sylvie Citerne Renaud Sergheraert Julie Lalande Batrice Teulat Emmanuelle Mounier Soulaiman Sakr Jrmy Lothier 《International journal of molecular sciences》2022,23(13)
Water deficit causes substantial yield losses that climate change is going to make even more problematic. Sustainable agricultural practices are increasingly developed to improve plant tolerance to abiotic stresses. One innovative solution amongst others is the integration of plant biostimulants in agriculture. In this work, we investigate for the first time the effects of the biostimulant –Leafamine®–a protein hydrolysate on greenhouse lettuce (Lactuca sativa L.) grown under well-watered and water-deficit conditions. We examined the physiological and metabolomic water deficit responses of lettuce treated with Leafamine® (0.585 g/pot) or not. Root application of Leafamine® increased the shoot fresh biomass of both well-watered (+40%) and deficit-irrigated (+20%) lettuce plants because the projected leaf area increased. Our results also indicate that Leafamine® application could adjust the nitrogen metabolism by enhancing the total nitrogen content, amino acid (proline) contents and the total protein level in lettuce leaves, irrespective of the water condition. Osmolytes such as soluble sugars and polyols, also increased in Leafamine®-treated lettuce. Our findings suggest that the protective effect of Leafamine is a widespread change in plant metabolism and could involve ABA, putrescine and raffinose. 相似文献
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555.
Multi-View Stereo Reconstruction and Scene Flow Estimation with a Global Image-Based Matching Score 总被引:2,自引:0,他引:2
Jean-Philippe Pons Renaud Keriven Olivier Faugeras 《International Journal of Computer Vision》2007,72(2):179-193
We present a new variational method for multi-view stereovision and non-rigid three-dimensional motion estimation from multiple
video sequences. Our method minimizes the prediction error of the shape and motion estimates. Both problems then translate
into a generic image registration task. The latter is entrusted to a global measure of image similarity, chosen depending
on imaging conditions and scene properties. Rather than integrating a matching measure computed independently at each surface
point, our approach computes a global image-based matching score between the input images and the predicted images. The matching
process fully handles projective distortion and partial occlusions. Neighborhood as well as global intensity information can
be exploited to improve the robustness to appearance changes due to non-Lambertian materials and illumination changes, without
any approximation of shape, motion or visibility. Moreover, our approach results in a simpler, more flexible, and more efficient
implementation than in existing methods. The computation time on large datasets does not exceed thirty minutes on a standard
workstation. Finally, our method is compliant with a hardware implementation with graphics processor units. Our stereovision
algorithm yields very good results on a variety of datasets including specularities and translucency. We have successfully
tested our motion estimation algorithm on a very challenging multi-view video sequence of a non-rigid scene.
Electronic supplementary material Electronic supplementary material is available for this article at and accessible for authorised users. 相似文献
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