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111.
In sustained forest management, it is particularly useful to test the adequacy of various silvicultural scenarios, but decision-making is also becoming increasingly complex because forest managers have to simultaneously meet several different objectives in response to society demands. In order to help forest managers make appropriate choices in silvicultural systems, we propose a SDSS (Silvicultural Decision Support System) that applies to pure and even-aged larch stands (Larix sp.) in lowland areas where site conditions are similar to those encountered in Southern Belgium. Its main purpose is (i) to predict the influence of silvicultural treatments on stand evolution and (ii) assist forest managers in comparing different scenarios with respect to predefined goals. This SDSS consists in three modules designed to elaborate silvicultural scenarios involving (i) stand growth prediction and thinning simulation; (ii) assessment of indicators selected to define the scenarios referring to wood production, financial, technico-economic and ecological components, tree stability and wood quality; and (iii) comparison of the scenarios on the basis of the set of previously assessed indicators (multi-criteria analysis). User-friendly “MGC_Larch” software helps managers to formulate, evaluate and compare different silvicultural scenarios for larch.  相似文献   
112.
Due to economic and ecological factors, European agricultural practices are likely to go towards extensive systems with lower inputs of nitrogen (N) fertilisers. The objective of this study was to assess varietal differences for N use at two nitrogen levels. A set of 20 winter wheat (Triticum aestivum L.) genotypes was studied over 2 years in northern France on a deep loam soil without (N0) and with 170 kg ha−1 N fertiliser (N+) as ammonium nitrate. Results were consistent on both years as the genotype×year or genotype×year×N level interactions were not significant. The genotype×N level interaction was highly significant except for total N utilisation efficiency (total above-ground dry weight/total above-ground N) and grain N concentration. The genotype×N level interaction for grain yield was mainly due to three contrasting genotypes: Cappelle, a cultivar from the 1940s, had the same yield at N0 and N+; Arche had a high yield at both N levels; and Récital had a high yield with added N and a very low one without N. The number of kernels/ear explained most of the variations of grain yield at N0 (48%) and N+ (80%), and of the interaction (67%). N uptake efficiency (total above-ground N/soil N supply) accounted for 64% of the variation in N use efficiency (grain yield/soil N supply), while at N0 and at N+ it accounted for only 30%. N utilisation efficiency (grain yield/total above-ground N) was then more important at N+ than at N0. Grain N explained most of total plant N variation at both N levels. The interaction for N use efficiency was best explained by the interaction of N uptake (63%). The applications of these results to a breeding programme to create varieties adapted to low-input management systems are discussed.  相似文献   
113.
Front-face fluorescence spectroscopy, directly applied on honey samples, was used for the authentication of 11 unifloral and polyfloral honey types (n = 371 samples) previously classified using traditional methods such as chemical, pollen, and sensory analysis. Excitation spectra (220-400 nm) were recorded with the emission measured at 420 nm. In addition, emission spectra were recorded between 290 and 500 nm (excitation at 270 nm) as well as between 330 and 550 nm (excitation at 310 nm). A total of four different spectral data sets were considered for data analysis. Chemometric evaluation of the spectra included principal component analysis and linear discriminant analysis; the error rates of the discriminant models were calculated by using Bayes' theorem. They ranged from <0.1% (polyfloral and chestnut honeys) to 9.9% (fir honeydew honey) by using single spectral data sets and from <0.1% (metcalfa honeydew, polyfloral, and chestnut honeys) to 7.5% (lime honey) by combining two data sets. This study indicates that front-face fluorescence spectroscopy is a promising technique for the authentication of the botanical origin of honey and may also be useful for the determination of the geographical origin within the same unifloral honey type.  相似文献   
114.
The present study sought to elucidate whether Schistosoma japonicum eggs could survive a passage through dogs and chickens. Three dogs and three chickens were used for the experiment. The dogs were allowed to eat goat faeces containing 80 S. japonicum eggs per gram. The chickens were given 2 ml of water containing more than 100 S. japonicum eggs per ml. The hatchability of the eggs was 51.8% prior to administration. All faeces were collected for 3 days from the dogs and for 2 days from the chickens and egg excretion and hatchability were measured. The results showed that nearly 50% of the eggs administered to the dogs were recovered in the faeces during the first 2 days and during the first 25 h 39% of the recovered eggs were viable and able to hatch. In the chickens 9% of the administered eggs were recovered within 27 h and within the first 3.5 h after administration 19% of the recovered eggs were viable and able to hatch. The results suggest that both dogs and chickens may act as transport hosts for S. japonicum in endemic areas.  相似文献   
115.
Genetic maps published for elite durum wheat (Triticum turgidum durum Desf.), were mainly related to Italian and North American pools. To provide additional information dedicated to durum elite pool, a recombinant inbred population (217 RILs) derived form 2 French commercial varieties (Ixos and Primadur), has been mapped with 529 loci (98 AFLPs, 67 SSRs, 1 ISBP and 363 DArTs). Genetic map spanned a total of 2,082 cM (5.7 cM/marker on average). Recombination rate variation over the genome was documented through the analysis of six segregating populations representing a total of 48 RILs × 6, issued from an half diallel design based on four elite lines—Neodur, Ixos, Lloyd and Primadur—including the 2 previous genitors. Each set of three genetically connected populations (48 RILs × 3) was used to build the consensus parental maps for each genitor. To construct the four consensus parental maps, marker ordering was determined on 217 RILs map which was an extended population of the most polymorphic cross (Ixos × Primadur). Sizeable, recombination rate variation has been observed between the four parental maps both at the marker pair scale and at the linkage group scale. Two of the parents, Lloyd and Primadur, had strong, opposite effects increasing and decreasing, respectively the recombination rate. Additional studies are proposed to increase our understanding of this variation, with the identification of environmental or genetic factors affecting recombination rate.  相似文献   
116.
Psoroptic mange is one of the most severe skin conditions of sheep. This highly contagious disease is responsible for huge economical losses in many sheep-raising countries. It is also a significant welfare concern. Our understanding of the biology of Psoroptes ovis and of the host-parasite relationship during psoroptic mange made remarkable progress during the last decade. These data combined with the availability of powerful molecular tools have opened new avenues of research. Clearly, there is still a long way to go before a vaccine becomes a reality. Additionally, other diagnostic tools and control methods should be further investigated such as breeding for genetic resistance and the use of biocontrol agents.  相似文献   
117.
Cervical spondylomyelopathy or Wobbler syndrome commonly affects the cervical vertebral column of Great Dane dogs. Degenerative changes affecting the articular process joints are a frequent finding in these patients; however, the correlation between these changes and other features of cervical spondylomyelopathy are uncertain. We described and graded the degenerative changes evident in the cervical articular process joints from 13 Great Danes dogs with cervical spondylomyelopathy using MR imaging, and evaluated the relationship between individual features of cervical articular process joint degeneration and the presence of spinal cord compression, vertebral foraminal stenosis, intramedullary spinal cord changes, and intervertebral disc degenerative changes. Degenerative changes affecting the articular process joints were common, with only 13 of 94 (14%) having no degenerative changes. The most severe changes were evident between C4-C5 and C7-T1 intervertebral spaces. Reduction or loss of the hyperintense synovial fluid signal on T2-weighted MR images was the most frequent feature associated with articular process joint degenerative changes. Degenerative changes of the articular process joints affecting the synovial fluid or articular surface, or causing lateral hypertrophic tissue, were positively correlated with lateral spinal cord compression and vertebral foraminal stenosis. Dorsal hypertrophic tissue was positively correlated with dorsal spinal cord compression. Disc-associated spinal cord compression was recognized less frequently.  相似文献   
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The aim of this study was to compare the influence of a high α-linolenic acid (ALA) diet (linseed diet) and a high linoleic acid (LA) diet (sunflower diet) on performances of pigs, on the dietetical quality of their tissues (adipose tissues and muscles), and on the lipogenic potential of these tissues. Growth and carcass performances, and the lipid content of the tissues were not affected by the diet. Feeding the linseed diet increased the content of n-3 PUFA and decreased the LA/ALA ratios in all the tissues, while the sunflower diet led to an increase in the n-6 PUFA contents. Neither the stearoyl-CoA-desaturase and glucose-6-phosphate-dehydrogenase activities nor the β-hydroxyacyl-CoA-dehydrogenase activity were affected by the diet. Acetyl-CoA-carboxylase and fatty acid synthase activities were enhanced with the linseed diet in respectively subcutaneous adipose tissue and intermuscular adipose tissue, while malic enzyme activity was decreased in liver and subcutaneous adipose tissue of pigs fed the linseed diet.  相似文献   
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