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141.
A number of multi-stakeholder initiatives (MSIs) and commodity roundtables have been created since the 1990s to respond to the growing criticism of agriculture’s environmental and social impacts. Driven by private and global-scale actors, these initiatives are setting global standards for sustainable agricultural practices. They claim to follow the new standard-making virtues of inclusiveness and consensus and base their legitimacy on their claim of balanced representation of, and participation by, all categories of stakeholders. This principle of representing a wide range of interests with a balance of power is at the heart of a new type of action that forms part of a broader political liberal model for building coalitions of interest groups. The intention of this symposium is to assess the nature of processes and outcomes of this model while paying particular attention to the forms of inclusion and exclusion they generate. In this introduction, we highlight the differences in theoretical approaches to analyzing MSIs and the manifestation of power through them. We distinguish between more traditional political–economy approaches and approaches concerned with ideational and normative power, such as convention theory. We discuss some of the main paradoxes of MSIs related to their willingness to be “inclusive” and at the same time their exclusionary or “closure” effects due in part to interactions with existing political economic contexts and embedded power inequalities, as well as more subtle manifestations of power linked to the favoring of some forms of knowledge and engagement over others. 相似文献
142.
Maxim Moreau Bertrand Lussier Laurent Ballaz Eric Troncy 《The Canadian veterinary journal. La revue veterinaire canadienne》2014,55(11):1057-1065
Over the past 2 decades the measurement of ground reaction forces (GRF) has been extensively used in dogs and cats to gain insights on normal locomotion, discrepancies under pathologic conditions, and biomechanical changes following surgical procedures. Ground reaction forces have become a well-established outcome measure of pain-related functional impairment in animals affected by experimental and naturally occurring osteoarthritis. This paper comprehensively reviews the nature of GRF and presents arguments regarding its measurement in osteoarthritis research. 相似文献
143.
Use of molecular markers for the development of new cultivars and the evaluation of genetic diversity 总被引:3,自引:1,他引:3
Molecular markers bring new information on the determinism of trait variation and the organisation of genetic diversity within
plant species of agricultural interest. We review here how this information can be used to increase the efficiency of plant
breeding programs, considering both theoretical analyses and recent experimental data. Use of mapping information to assemble
alleles of interest is discussed first, considering an increasing complexity in trait determinism and its consequences on
the breeding schemes. Experimental data now confirm the efficiency of these approaches. They call however, for (i) a better
modelling of phenotype determinism, to better anticipate the final effect of marker assisted selection and (ii) studies that
would address trait variation determinism within a broad diversity, to increase the probability to identify alleles of key
interest and identify stable marker-trait associations. Recent promising developments in genetic diversity analysis are discussed
with respect to these last objectives.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
144.
Plant sterols (phytosterols) have been shown to possess serum cholesterol-lowering properties. In recent years, several phytosterol-enriched functional food products have been developed and marketed. Some phytosterol products contain common unsaturated sterols and some contain a subset of phytosterols called phytostanols (saturated sterols, also called plant stanols). Current methods for the quantitative analysis of plant sterols are labor intensive and require sophisticated gas or liquid chromatographs. In this study, a popular commercial spectrophotometric serum cholesterol test kit was evaluated for the analysis of plant sterols. The results indicate that the method could be modified to analyze phytosterols and phytostanols by increasing the incubation time. Both free phytosterols and fatty acyl phytosteryl esters were quantitatively analyzed, but ferulate phytosteryl esters, such as those that are found in corn and other cereals, were not hydrolyzed by the enzymes in the test kit and therefore were not detected. 相似文献
145.
P M Moreau 《The Veterinary record》1990,126(17):415-425
146.
Oshikane H Sheppard K Fukai S Nakamura Y Ishitani R Numata T Sherrer RL Feng L Schmitt E Panvert M Blanquet S Mechulam Y Söll D Nureki O 《Science (New York, N.Y.)》2006,312(5782):1950-1954
Glutaminyl-transfer RNA (Gln-tRNA(Gln)) in archaea is synthesized in a pretranslational amidation of misacylated Glu-tRNA(Gln) by the heterodimeric Glu-tRNA(Gln) amidotransferase GatDE. Here we report the crystal structure of the Methanothermobacter thermautotrophicus GatDE complexed to tRNA(Gln) at 3.15 angstroms resolution. Biochemical analysis of GatDE and of tRNA(Gln) mutants characterized the catalytic centers for the enzyme's three reactions (glutaminase, kinase, and amidotransferase activity). A 40 angstrom-long channel for ammonia transport connects the active sites in GatD and GatE. tRNA(Gln) recognition by indirect readout based on shape complementarity of the D loop suggests an early anticodon-independent RNA-based mechanism for adding glutamine to the genetic code. 相似文献
147.
Casrouge A Zhang SY Eidenschenk C Jouanguy E Puel A Yang K Alcais A Picard C Mahfoufi N Nicolas N Lorenzo L Plancoulaine S Sénéchal B Geissmann F Tabeta K Hoebe K Du X Miller RL Héron B Mignot C de Villemeur TB Lebon P Dulac O Rozenberg F Beutler B Tardieu M Abel L Casanova JL 《Science (New York, N.Y.)》2006,314(5797):308-312
Herpes simplex virus-1 (HSV-1) encephalitis (HSE) is the most common form of sporadic viral encephalitis in western countries. Its pathogenesis remains unclear, as it affects otherwise healthy patients and only a small minority of HSV-1-infected individuals. Here, we elucidate a genetic etiology for HSE in two children with autosomal recessive deficiency in the intracellular protein UNC-93B, resulting in impaired cellular interferon-alpha/beta and -lambda antiviral responses. HSE can result from a single-gene immunodeficiency that does not compromise immunity to most pathogens, unlike most known primary immunodeficiencies. Other severe infectious diseases may also reflect monogenic disorders of immunity. 相似文献
148.
Cambon E Gouzou F Pina M Barea B Barouh N Lago R Ruales J Tsai SW Villeneuve P 《Journal of agricultural and food chemistry》2006,54(7):2726-2731
The enzymatic properties of Plumeria rubra latex have been evaluated for the first time, showing a high activity in both hydrolysis and synthesis reactions, and compared to the biocatalytic behavior of babaco (Vasconcellea x Heilbornii cv.) latex. Both biocatalysts have been optimized by studying the various parameters that influence reaction kinetics. The optimum temperatures for hydrolysis reactions were 50 and 55 degrees C for babaco and Plumeria, respectively. The optimum pH for babaco latex was 7, whereas for Plumeria latex, two optimal pH values (4 and 7) were observed. With regard to esterification and acyl transfer reactions such as alcoholysis and interesterification, the influence of thermodynamic water activity on reaction yields was determined and correlated with water sorption and desorption isotherms. When babaco latex is used as a biocatalyst, optimal synthesis reaction yields are obtained when the enzymatic extract is stabilized at a water activity value of 0.38, which corresponds to a water content of 5.7%. This optimal level of hydration is located on the linear portion of the biocatalyst's sorption isotherm, where the water molecules exhibit high-energy interactions with the protein network. In synthesis reactions (esterification, alcoholysis, and interesterification) biocatalyzed by Plumeria latex, correlation between best reaction yields and water activity cannot be done. Indeed, the sorption isotherm plot has an atypical shape, indicating that water might be trapped in the latex matrix and, consequently, that the water content of the biocatalyst is highly dependent on the hydration history of the latex. 相似文献
149.
150.
Léa Bedel Arnaud Legout Anne Poszwa Gregory van der Heijden Mélanie Court Noémie Goutal-Pousse Emmanuelle Montarges-Pelletier Jacques Ranger 《Annals of Forest Science》2018,75(4):103