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401.
Alessandro Bonanno 《Agriculture and Human Values》1998,15(3):223-242
In liberal thought, democracy is guaranteed by the unity of community and government. The community of citizens elects its government according to political preferences. The government rules over the community with powers that are limited by unalienable human, civil, and political rights. These assumptions have characterized Classical Liberalism, Revisionist Liberalism, and contemporary Neo-Liberal theories. However, the assumed unity of community and government becomes problematic in Global Post-Fordism. Recent research on the globalization of the economy and society has underscored the increasing inability of nation-states to exercise power over their communities, which, in turn, limits the ability of communities to express their will at the nation-state level. The current phase of capitalism is characterized by socio-economic relations that transcend the jurisdictions of nation-states and local spaces. By introducing features characteristic of Classical Liberalism, Revisionist Liberalism and Neo-liberalism, and the contribution of the theory of Reflexive Modernization, which represents a novel attempt to rethink democracy within the liberal tradition, the issue of the fracture of the unity of community and government can be addressed. The inability of governments to control economic and non-economic environments creates a crisis of representation that implies serious limits to liberal democracy. This situation is particularly important for the agricultural and food sector since its development and programs for its democratization have been historically based on the intervention of agencies of and control by the nation-state. 相似文献
402.
Antonello Sala Joana dArc Prat Farran Josefina Antonijuan Alessandro Lucchetti 《Fisheries Research》2009,100(2):156-166
A new door has been designed to reduce hydrodynamic drag coefficient and increase spread of door commonly used in the Mediterranean commercial demersal trawl fisheries. Flume tank testing and engineering sea trials provide data which allow us to illustrate the performance and impact on the seabed of an existing door and a new door design. In the flume tank, each model was tested over a range of attack angles and for a limited range of otterboard heels. Curves of spreading-, drag- and down-force coefficients have been calculated. In the case of sea trials in order to extract the hydrodynamic coefficients an analysis has been applied and a mathematical model was used to calculate attack angle functions. From analysing the differences between engineering sea trials and flume tank tests we have deduced some conclusions about additional ground contact forces on sea trials that affect the performance of the doors. Moreover, a comparison between reaction forces of the flume tank and the estimation of reaction forces at sea has been given. Finally, this study allowed us to notice important differences between traditional and experimental otterboards. 相似文献
403.
Silvia L. Toffolatti Giuliana Maddalena Demetrio Marcianò Alessandro Passera Fabio Quaglino 《Plant pathology》2020,69(9):1695-1707
Botrytis cinerea, the grey mould agent, is one of the most important pathogens of grapevine, due to the great yield losses caused and the economic costs related to disease control. Ground cover plants are assumed to have a role in the complex epidemiology of the pathogen, even if no information on the genetic variability of the strains is available. In this study, a molecular epidemiology approach, based on the comparative analysis of the nucleotide sequences of multiple genes (ITS1-ITS2, G3PDH, NEP1, NEP2, BC-hch, and sdhB), was used to evaluate whether B. cinerea isolated from herbaceous species contributes to grey mould diffusion on grapevines. From 330 samples collected in two vineyards in Lombardy, Italy, 63 B. cinerea strains were isolated from tissues of grapevine with symptoms (50 strains) and spontaneous ground cover plants (13 strains). Capsella bursa-pastoris, Cardamine impatiens, Lamium purpureum, and Crepis tectorum were identified as novel B. cinerea hosts. Sequence analysis and phylogeny showed that the same genotypes were present on both grapevines and herbaceous plants, with no fitness (estimated from growth and sporulation on potato dextrose agar) or pathogenicity (on grapevine leaves and berries, and tomato leaves) penalties. This confirms that ground cover plants can be a source of inoculum for B. cinerea on grapevine. Moreover, phylogenetic analysis of the BC-hch gene allowed the identification of two genetically distinct clusters, characterized by vegetative incompatibility and different distributions of the mating types, fitness, and pathogenicity. Therefore, B. cinerea seems to be composed of two diverging subpopulations that do not differ for host specialization. 相似文献
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406.
Antonello Sala Alessandro Lucchetti Corrado Piccinetti Mario Ferretti 《Fisheries Research》2008,93(1-2):8-21
Mediterranean demersal trawl fisheries traditionally operate using small diamond-shape meshes in the codend, which tend to retain almost all animals. We investigated the effect of mesh configuration on the size selectivity of nine species (the scaldfish Arnoglossus laterna, the broad-tail shortfin squid Illex coindettii, the European hake Merluccius merluccius, the red mullet Mullus barbatus, the Norway lobster Nephrops norvegicus, the common pandora Pagellus erythrinus, the deepwater rose shrimp Parapenaeus longirostris, the Mediterranean horse mackerel Trachurus mediterraneus and the poor-cod Trisopterus minutus capelanus) commonly captured in the Mediterranean demersal trawls. Two codends having meshes with the same opening (ca. 38 mm) but different mesh configuration (DM38: diamond-mesh and SM38: square-mesh configuration) were fished daily and alternately on the same trawl. They demonstrated a substantial improvement in selectivity with square-mesh. Selectivity was measured using the covered codend technique, the cover being supported by circular hoops.The results were analysed taking into account the between-haul variation in selectivity. Two other important external variables were identified: the trawling depth and the codend catch, which for some species influenced between-haul variation, but there was no evidence of a coherent effect on selectivity parameters.The selectivity of 40 mm diamond-mesh codend has been reported to be rather poor because a large proportion of the codend catch is immature and smaller than the minimum landing size (MLS) or first maturity size. With the exception of the flatfish (A. laterna), the effect of a change of mesh configuration from diamond- to square-mesh on size selectivity positively affected the retention length at 50% (L50). However, square-meshes were found to be unsuitable for flat and/or deep-bodied fish as these escape more readily from diamond-meshes.The Council Regulation (EC) No. 1967/2006, concerning management measures for the sustainable exploitation of fishery resources in the Mediterranean, establishes the MLS of marine organisms. However, the increase in L50 with square-mesh would not avoid some of the existing contradictions in allowing the use of codend mesh which leads to lower L50 than the MLS. 相似文献