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The amount of improved seed used in Nigeria is extremely low. Overall, only 5–10% of cultivated land is planted with improved seeds, and about 10% of rural farmers use improved varieties. The objective of this investigation was to identify determinants of adoption of improved seed by farmers not participating in and those participating in the federal government’s e-wallet program in Nigeria. We determined the impact of the e-wallet program on adoption of improved seed in rural areas. A total of 1200 rural farmers were sampled across six geopolitical zones of Nigeria. Results from the use of a bivariate probit model indicated that the e-wallet program continued to become increasingly popular among rural farmers; and that farmers’ literacy, ownership of a mobile phone, value output, mobile network coverage, power for charging phone batteries and contact with extension agents were the positive determinants of farmer participation in the e-wallet program. Cultural obstacles to married women, growers’ age, and increased distance to registration and input collection centers reduced farmers’ tendency to participate in the e-wallet program. The results also showed that rural farmers depended on the e-wallet program for increased use and adoption of improved seed in Nigeria, to boost food security in sub-Saharan Africa. The results suggested the need for an improved e-wallet model by lessening constraints mostly associated with rural information and communication infrastructure, and distance to the registration and input collection centers. 相似文献
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Weak effects of habitat type on susceptibility to invasive freshwater species: an Italian case study 下载免费PDF全文
Angela Boggero Alberto Basset Martina Austoni Enrico Barbone Luca Bartolozzi Isabella Bertani Alessandro Campanaro Antonella Cattaneo Fabio Cianferoni Giuseppe Corriero Ambrosius Martin Dörr A. Concetta Elia Gentile Francesco Ficetola Lyudmila Kamburska Gianandrea La Porta Sara Lauceri Alessandro Ludovisi Elda Gaino Enzo Goretti Massimo Lorenzoni Marina Manca Aldo Marchetto Giuseppe Morabito Francesco Nonnis Marzano Alessandro Oggioni Cataldo Pierri Nicoletta Riccardi Giampaolo Rossetti Nicola Ungaro Pietro Volta Silvia Zaupa Diego Fontaneto 《水产资源保护:海洋与淡水生态系统》2014,24(6):841-852
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Anna Ilyina Roberto Arredondo-Valdés Salavat Farkhutdinov Elda Patricia Segura-Ceniceros José Luis Martínez-Hernández Radik Zaynullin Rayhana Kunakova 《Plant foods for human nutrition (Dordrecht, Netherlands)》2014,69(1):65-70
In vitro effect of betulin-containing extract from Betula pendula Roth. bark on alpha-amylase activity was studied, the kinetic mechanism of interaction was proposed and in vivo effect of betulin-containing extract on weight gain and meat quality of broiler chickens was evaluated. The highest level of inhibitory activity (20 %) was detected in extract concentration of 1,000 mg/L. Increased extract concentration did not lead to increased enzyme inhibition. Using Dixon and Cornish-Bowden coordinates, the competitive mechanism of inhibition was demonstrated. Calculated kinetic parameters were: Km equal to 0.6 mg/mL, Vmax equal to 2.6 and 2.1 mM/min from Lineweaver-Burk and Dixon coordinates, respectively and Ki equal to 3,670?±?230 mg/mL. The partial inhibition of enzyme indicates the existence of low concentration of active inhibitory form, which reaches saturation level with increased extract concentration in applied suspension. Therefore, Ki has an apparent constant character. This partial inhibition of amylase activity observed in in vitro assay did not affect weight gain and meat quality of broiler chickens during in vivo assay. Rather, the tendency to increase the weight of edible parts and muscles compared to diet without additive suggests that the extract may be a potential food additive in poultry farming. Additionally, it could be a source for further pharmaceutical and pharmacological research. 相似文献
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Nunes CM Lima VM Paula HB Perri SH Andrade AM Dias FE Burattini MN 《Veterinary parasitology》2008,153(1-2):19-23
Measures employed to control visceral leishmaniasis in Brazil have focused on vector control by residual insecticide spraying and diagnosis of infection with elimination of positive dogs. We describe dog culling and replacement in a Brazilian endemic area (the Alvorada District, Ara?atuba, SP) in order to better understand dog population dynamics when elimination of the dog reservoir is adopted as the main control measure. From August 2002 to July 2004, 60.9% of the estimated dog population for the area was culled with a mean age of 34 months old. The presence of anti-Leishmania sp. antibodies was recorded for only 26.7% of the euthanized canines. Replacement was observed in 38.8% of the cases, some of them by 2 or more dogs and in a mean time of 4 months. Dogs were replaced mostly by puppies of both sexes with a mean age of 6.8 months. From August 2002 to April 2005 we were able to follow-up 116 of these dogs, during a mean time of 8.7 months. Canine visceral leishmaniasis seropositivity by ELISA was observed in 42.2% of the followed dogs, 30.6% of which were already positive at the first evaluation. By the end of the follow-up period 37% of the dogs were submitted to euthanasia, with a mean age of 18.3 months. In the studied CVL endemic area of Brazil, euthanasia and the subsequent replacement ratio were high, increasing the dog population turnover and leading to a younger population that might be more susceptible to a variety of other infectious diseases in addition to CVL. Dog culling as a control strategy for VL should be reassessed. 相似文献
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Delgado-Balbuena Laura Romero-Tepal Elda M. Luna-Guido Marco L. Marsch Rodolfo Dendooven Luc 《Water, air, and soil pollution》2013,224(2):1-8
Water, Air, &; Soil Pollution - Suspended microplastic and black carbon (BC) particles were determined in surface waters of the Jade system, southern North Sea, including freshwater sources. On... 相似文献
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