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81.
Liv Pommer Jensen Kim Picozzi Octavio da Costa Monteiro de Almeida Marcelino de Jesus da Costa Luc Spyckerelle William Erskine 《Food Security》2014,6(3):397-409
Factors related to adoption of new agricultural technologies have been given increasing attention, especially in developing countries where such technologies offer opportunities to increase food production. One of the most immediate ways to improve food production significantly is through the adoption of high yielding varieties of food crops, but rates of adoption are often low, especially among the rural poor. In Timor-Leste, improved varieties of food crops with yield advantages across all agro-ecological zones have been introduced. However, despite yield advantages, suitability and high levels of food insecurity, discontinuance occurs and adoption rates are low. To identify factors related to adoption of the improved varieties across agro-ecological zones, binary logistic regression was performed on data collected from 1511 rural households. The results identified several factors related to adoption and showed that their impact varied across agro-ecological zones. The factor most strongly related to adoption was having a relationship to a grower of an improved variety of food crop and the closeness of this relationship. Furthermore, the following factors were related to adoption with variation across agro-ecological zones: age; education; size of farming plots; travel time between household and farming plot; involvement with the programme developing the improved varieties of food crops and participation in groups and training programmes. Overall, the findings of this study emphasize that dissemination strategies should embrace social relationships and be sensitive to agro-ecological zones. 相似文献
82.
Fillets of Sparus aurata were marinated in a mixture of salt (5.5%) and citric acid (48.9 g/kg) for 1 h, then vacuum packed and refrigerated for 1, 5, 16, and 21 d. Structural and ultrastructural parameters were evaluated in 6 specimens per time period. At day 1, the preservative solution appeared among the muscle fibers, thus increasing the interfibrillar spaces; cytoplasmic organelles were swollen and the sarcolemma-endomysium appeared very altered and electron-dense. At 5 to 10 d, the marinade solution had penetrated into the muscle fibers. The subsarcolemmal and intermyofibrillar spaces were dilated and granular lines of electron-dense material appeared among the fibers. From 16 d, broad interfibrillar spaces were occupied by granular material derived from denatured sarcolemma-endomysium and denatured myofibrils. Sarcomeres were already altered from initial stages, mainly at the I-band level. The Z-line also appeared disrupted. Such alterations were more severe from 10 d on, such that most of the sarcomeres showed disintegration of myofilaments. 相似文献
83.
Octavio Armas Jos Rodríguez Francisco Payri Jaime Martín John R. Agudelo 《Applied Thermal Engineering》2005,25(17-18):2842-2853
The use of the polytropic coefficient calculation during the compression process in the thermodynamic cycle of a reciprocating internal combustion engine is an interesting tool to minimize errors in the synchronization of pressure and volume signals, and to determine heat flux transferred to the cylinder walls. The accuracy of this calculation depends on the instantaneous values for pressure, volume, trapped mass and its composition, as well as on their variations. In this work the effect of the errors in blow-by, trapped mass and its composition have been studied in detail, specially the effect of errors in the composition estimation, owing to the use of exhaust gas recirculation in typical diesel engines. 相似文献
84.
Luis A Bello‐Prez Perla Osorio‐Díaz Edith Agama‐Acevedo Javier Solorza‐Feria Jorge F Toro‐Vzquez Octavio Paredes‐Lpez 《Journal of the science of food and agriculture》2003,83(5):408-412
Commercial ‘masas’ and dry ‘masa’ flours (DMFs) were evaluated for chemical composition, water retention capacity (WRC), gelatinization, retrogradation and X‐ray diffraction. Both masas and DMF had similar chemical compositions. The masas had higher soluble carbohydrate contents and lower WRCs than DMF. In the same way, DMFs had lower gelatinization temperatures and enthalpies of gelatinization than masas. These results were confirmed by X‐ray diffraction analysis showing a lower degree of crystallinity in DMFs than in masas. The melting temperature in retrogradated samples of both masas and DMFs had a tendency to increase as storage time increased. This increment was more apparent with the enthalpy of melting. These results were probably associated with crystal perfection during starch retrogradation, ie recrystallization of gelatinized starch occurred as a time‐dependent process. Copyright © 2003 Society of Chemical Industry 相似文献
85.
In this work the influence of the cooling fin shape on the pressure drop caused by flow resistance of a heat sink is studied. A new manner to optimise heat sinks is developed, bringing the emphasis not only on maximum heat transfer flux, but also on minimum flow resistance. The study is done numerically using the computational fluid dynamic software FLUENT. The results show the advantages of using aerodynamic shaped fins if the Reynolds number, based on the spacing between the cooling fins, is greater or equal than about 800. Some preliminary profile shapes are suggested. The authors consider this research as a quite unique approach as compared to other research where the flow resistance has not been taken into account. 相似文献
86.
R Larraga FJ Manero S Bell Y Herrero E Chacón A Hernández 《Canadian Metallurgical Quarterly》1998,15(10):538-540
We describe two patients with diffuse alveolar hemorrhage and Wegener s Granulomatosis. In both cases, ANCA were demonstrated. We discuss the profit about ANCA s in the diagnosis and management the systemic vasculitis. 相似文献
87.
88.
L. M. Camarinha-Matos Octavio Castolo Walter Vieira 《Journal of Intelligent and Robotic Systems》2002,35(1):1-22
This paper presents the use of adaptive mobile agents for remote operation, enabling real-time response in spite of the limitations of the communication channels in terms of time-delays, availability, and reliability. Autonomy of the mobile agents is achieved through high levels of intelligence including execution monitoring and error recovery. Potential applications range from traditional telerobotics to virtual laboratories where mobile agents act as representatives of users in scientific experiments. Practical results are presented in a scenario where a SCARA-type robot is remotely commanded through the Internet. 相似文献
89.
Santana Suarez Octavio; Perez Aguiar Jose Rafael; Losada Garcia Luis; Carreras Riudavets Francisco Javier 《Literary and Linguistic Computing》2006,21(2):187-197
This article presents a disambiguation method which diminishesthe functional combinations of the words of a sentence takinginto account the context in which they appear. This processis built in two phases: the first phase is based on the localsyntactic structures of the Spanish language and reaches anaverage yield of 87%. The second one is supported by syntactictree representation and pushes the results up to an approximatehigh end of 96%. This process constitutes the starting pointtowards an automated syntactic analysis. 相似文献
90.
Donato A. G. Aranda Rafael T. P. Santos Neyda C. O. Tapanes André Luis Dantas Ramos Octavio Auqusto C. Antunes 《Catalysis Letters》2008,122(1-2):20-25
This work deals with esterification of palm fatty acids to produce biodiesel in a batch reactor, using homogeneous acid catalysts,
evaluating the effect of the alcohol used, presence of water, type and concentration of catalysts. Methanesulfonic and sulfuric
acid were the best catalysts. Reaction with methanol showed greater yields. It was showed very clearly that the presence of
water in the reaction medium showed a negative effect in the reaction velocity. Kinetic parameters were estimated and molecular
modeling was performed. Protonation of the carboxylic moiety of the fatty acid were defined as rate determinant step for the
reaction. 相似文献