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Efeitos das barreiras não tarifárias nas exportações de manga in natura
(Universidade Federal de São Carlos, 2006-10-27) Costa, Luana Gonçalves Euclydes Borges da; Alcântara, Rosane Lúcia Chicarelli; https://lattes.cnpq.br/5637223686801560
The fruit sector is found in expansion, being considered one of the fastest emerging and potential in the Brazilian agribusiness. The fruit chain has been affected by the increase in global competitiveness, where the big producers and retailers, focusing on the strengthening of their competitive position have amplified their strategies and acquisitions leading to a greater market concentration, a greater asymmetry of power and more complex configuration of this chain worldwide. The mango is in the spotlight in the Brazilian fruit culture, it is the third best exported fruit (113 thousand tons) in 2005. Brazil was eighth in worldwide production of mango in 2005, producing 850.000 tons. The northeast was the main productive area, responsible for 66% of all national production. The fruit sector is strongly affected by non-tariff barriers (NTBs), especially technical and phytosanitary. The restrictions have represented serious obstacles to the Brazilian fruit culture expansion in the international market. Therefore, the general goal of this research was analyze the productive chain of the exported Brazilian mango, focusing on the imposition of non-tariff barriers in the production, harvest, post harvest and distribution of national producers of mango in natura, where the study of case was selected as a more adequate method for the research and thus as multicase study was carried through. Some results found stand out: the technical barriers (having a phytosanitary state) are more frequent in mango exportation; the fruit is sold indirectly; the agriculture practice and non-tariff barriers are interrelated and finally, the consume behavior in different markets and consumers interfere in the process and practices adopted by the producers.
Síntese e avaliação da atividade biológica de uma coleção de amidas
(Universidade Federal de São Carlos, 2006-10-27) Castral, Thaís Corrêa; Corrêa, Arlene Gonçalves; https://lattes.cnpq.br/7425467156776144; https://lattes.cnpq.br/0124878003601321
The present study describes the preparation of amides containing the methylenedioxyphenyl group and also their activity against the leaf-cutting ant, Atta sexdens rubropilosa, its symbiotic fungus Leucoagaricus gongylophorus and the fall armyworm, Spodoptera frugiperda, larvae. From the bioassays it was observed that N-piperidine-3-(3 ,4 - methylenedioxyphenyl)-2-(E)-propenamide (65) was the most promising as insecticide agent among the compounds studied against S. frugiperda with an LD50=1.07 µg/mg larvae. Amide 65 and N,N-diethyl-3-(3 ,4 - methylenedioxyphenyl)-2-(E)-propenamide (66) were the most active against the symbiotic fungus; and N-pirrolidine-3-(3 ,4 -methylenedioxyphenyl)-2-(E)- propenamide (67) and N-benzyl-3-(3 ,4 -methylenedioxyphenyl)-2-(E)- propenamide (72) against the leaf-cutting ant. Additional studies were necessary to establish the structure activity relationship for piperamides. Thus, Combinatorial Chemistry technologies were employed and a solution-phase synthesis of indexed collection of amides was carried out, identified by Gas Chromatography coupled with Mass Spectroscopy (GC/MS), and screened against S. frugiperda. From this library, the most active compound identified was 1-[4- (trifluoromethoxy)benzoyl]piperidine, A8B1, which was then individually synthesized and evaluated. It has shown a LD50 = 8,15 µg/mg larvae, thus less active than amide 65 against S. frugiperda.
Níveis de citocinas em bovinos (Bos indicus) desafiados com o carrapato Boophilus microplus (Cannestrini, 1887)
(Universidade Federal de São Carlos, 2006-10-27) Nakata, Liliane Cristina; Regitano, Luciana Correia de Almeida; https://lattes.cnpq.br/2807449233083227
Boophilus microplus tick affects cattle productivity causing economic losses in the order of billions of dollars annually. It is know that tick saliva exert immunomodulatory effects, an evolutionary adaptation to the immune response of the host that can counteract tick feeding. It has been suggested that the outcome of many parasitic infections with regard to resistance or susceptibility is determined by the pattern of response involving Th1 and Th2 cells, which produce specific cytokines that may direct the immune response towards different mechanisms. Limited information is available regarding to the host response to B. microplus tick infestation. In an attempt to improve our knowledge about cattle immune-response to ticks, this work determined the expression levels of cytokines mRNAs in two groups of Nelore (Bos indicus) calves: one control and other challenged by tick infestation. Our results demonstrated a down-regulation of IL-2 (P < 0.03) mRNA levels in challenged animals, while no effect of tick challenge was observed for IL-4, IL-8, IL-12p35, TNF-α and MCP-1. The down regulation of an important Th1 cytokine suggests a tendency towards a Th2 response pattern, which is in agreement with similar studies conducted with other tick-host models.