957 resultados para MACULATUS SAY
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Choosing properly and efficiently a supplier has been challenging practitioners and academics since 1960’s. Since then, countless studies had been performed and relevant changes in the business scenario were considered such as global sourcing, quality-orientation, just-in-time practices. It is almost consensus that quality should be the selection driver, however, some polemical findings questioned this general agreement. Therefore, one of the objectives of the study was to identify the supplier selection criteria and bring this discussion back again. Moreover, Dickson (1966) suggested existing business relationship as selection criterion, then it was reviewed the importance of business relationship for the company and noted a set of potential negative effects that could rise from it. By considering these side effects of relationship, this research aimed to investigate how the relationship could influence the supplier selection and how its harmful effects could affect the selection process. The impact of this phenomenon was investigated cross-nationally. The research strategy adopted was a controlled experiment via vignette combined with discrete choice analysis. The data collections were performed in China and Brazil. By examining the results, it could be drawn five major findings. First, when purchasers were asked to declare their supplier selection priorities, quality was stated as the most important independently of country and relationship. This result was consistent with diverse studies since 60’s. However, when purchasers were exposed to a multi-criteria trade-off situation, their actual selection priorities deviate from what they had declared. In the actual decision-making without influence of buyer-supplier relationship, Brazilian purchasers focused on price and Chinese buyers prioritized delivery then price. This observation reinforced some controversial prior studies of Verma & Pullman (1998) and Hirakubo & Kublin (1998). Second, through the introduction of the buyer-supplier relationship (operationalized via relational capital) in the supplier selection process, this research extended the existing studies and found that Brazilian buyers still focused on price. The relationship became just another criterion for supplier selection such as quality and delivery. However, from the Chinese sample, the results suggested that quality was totally discarded and the decision was majorly made through price and relationship. The third finding suggested that relational capital could legitimate the quality and sustainability of the supplier and replaces these selection criteria and made the decisional task less complex. Additionally, with the relational capital, the decision-makings were associated to few biases such as availability cognition, commitment, confirmatory and perceived biases. By analyzing the purchasers’ behavior, relational capital inducted buyers of both countries to relax in their purchasing requirements (quality, delivery and sustainability) leading to potential negative effects. In the Brazilian sample, the phenomenon of willing to pay a higher price for a lower quality offer demonstrated to be a potential counterproductive and suboptimal decision. Finally, the last finding was associated to the cultural effect on the buyers’ decisions. From the outcome, it is possible to observe that if a purchaser’s cultural background is more relation-oriented, the more he will tend to use relational capital as a decision heuristic, thus, the purchaser will be more susceptible to the potential relationship’s side effects
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GOMES, Carlos E. M. et al. Effect of trypsin inhibitor from Crotalaria pallida seeds on Callosobruchus maculatus (cowpea weevil) and Ceratitis capitata (fruit fly). Plant Physiology and Biochemistry (Paris), v. 43, n. 12, p. 1095-1102, 2005.ISSN 0981-9428. DOI:10.1016/j.plaphy.2005.11.004.
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Chitin is an important structural component of the cellular wall of fungi and exoskeleton of many invertebrate plagues, such as insects and nematodes. In digestory systems of insects it forms a named matrix of peritrophic membrane. One of the most studied interaction models protein-carbohydrate is the model that involves chitin-binding proteins. Among the involved characterized domains already in this interaction if they detach the hevein domain (HD), from of Hevea brasiliensis (Rubber tree), the R&R consensus domain (R&R), found in cuticular proteins of insects, and the motif called in this study as conglicinin motif (CD), found in the cristallography structure of the β-conglicinin bounded with GlcNac. These three chitin-binding domains had been used to determine which of them could be involved in silico in the interaction of Canavalia ensiformis and Vigna unguiculata vicilins with chitin, as well as associate these results with the WD50 of these vicilins for Callosobruchus maculatus larvae. The technique of comparative modeling was used for construction of the model 3D of the vicilin of V. unguiculata, that was not found in the data bases. Using the ClustalW program it was gotten localization of these domains in the vicilins primary structure. The domains R&R and CD had been found with bigger homology in the vicilins primary sequences and had been target of interaction studies. Through program GRAMM models of interaction ( dockings ) of the vicilins with GlcNac had been gotten. The results had shown that, through analysis in silico, HD is not part of the vicilins structures, proving the result gotten with the alignment of the primary sequences; the R&R domain, although not to have structural similarity in the vicilins, probably it has a participation in the activity of interaction of these with GlcNac; whereas the CD domain participates directly in the interaction of the vicilins with GlcNac. These results in silico show that the amino acid number, the types and the amount of binding made for the CD motif with GlcNac seem to be directly associates to the deleterious power that these vicilins show for C. maculatus larvae. This can give an initial step in the briefing of as the vicilins interact with alive chitin in and exert its toxic power for insects that possess peritrophic membrane
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Grains and legume seeds are foods that form the basis of the diets of many cultures around the world, winch contritbute to the daily nutrient requirements of humans. Vicilins (7S globulin) are storage proteins found in legume seeds, and may have an additional function constitutive defense of the embryo against pests and pathogens. In this work the vicilin from Anadenanthera macrocarpa - AmV (red-angico), was purified and partially characterized, its effect on development and larval survival and adult emergence of Callosobruchus maculatus was evaluated by determination of LD50, WD50 and ED50 in system bioassay. Purification of vicilin was initiated by the chitin affinity chromatography and then gel filtration (Superdex 75 Tricorn 10x300 mm) FPLC system followed by reverse phase chromatography (C8 phenomenex) on HPLC system. Bioassays WD50 and LD50 for larvae were 0.32% and 0.33% (w:w) respectively, since the ED50 for adults was 0.096%. The probable mechanism of action was evaluated by testing digestibility of AmV in vitro, and observed for the involvement of two fragments vicilins immunoreactive against polyclonal Anti-vicilin from Erythrina velutina (Anti-EvV) about of 22 and 13 kDa chitin binding. The AmV in its native form has been recognized by the anti-EvV, indicating that there is a conserved region in the vicilin and is probably corresponding to the chitin binding domains. These results point to a new vicilin chitin binding that can subsequently be used as a possible biopesticide protein source, in order to control insect pest C. maculatus and confirm literature findings that demonstrate vicilin in the presence of different kinds of ligands to conserved regions chitin not yet characterized
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Visando avaliar os efeitos de diferentes temperaturas de armazenamento e de genótipos de feijoeiro, Phaseolus vulgaris L., sobre a expressão da resistência ao caruncho, Acanthoscelides obtectus (Say), realizaram-se ensaios com os genótipos Arc.1S, Arc.1, Arc.2, Arc.4 e Carioca Pitoco. Os grãos de Arc.1S e Arc.2 expressaram resistência a A. obtectus nas temperaturas de 20ºC, 25ºC e 30°C; a resistência do genótipo Arc.1 diminuiu à medida que a temperatura de armazenamento foi elevada de 25ºC para 30ºC. A interação genótipos x temperaturas foi significativa, indicando que a elevação da temperatura afeta a expressão da resistência. A temperatura de 20ºC foi a mais adequada para discriminar os genótipos de feijoeiro, quanto a resistência.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Orius insidiosus (SAY, 1832) is an important predator for biological pest control programs. The objective of this work was to evaluate the functional response, predation capacity and reproductive aspects of O. insidiosus when predating 1, 5, 10, 15, and 20 third/fourth instar nymphs of Aphis gossypii. The tests were conducted under laboratory conditions. Females of the predator were individually maintained in Petri dishes with a cotton leaf at each one of the aphid densities. The average rate of predation was of 0.93 [plus or minus] 0.13, 3.58 [plus or minus] 0.80, 7.31 [plus or minus] 1.45, 7.40 [plus or minus] 1.16, and 10.54 [plus or minus] 1.84 at the densities of 1, 5, 10, 15, and 20 aphids, respectively. The results showed an attack rate of 0.10 h-1 and 1.82 h of manipulation time. The predator spent 3.10 to 4.08 h feeding on leaf cotton glands; this behavior was not directly influenced by the prey density. The proportion of egg laying per female grew up to the density of 10 nymphs whereas the number of eggs per laying increased with the number of available preys.
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The objective of this research was to determine the survival, reproduction and predaceous capacity of Orius insidiosus on cotton aphid Aphis gossypii. Cotton plants of Antares, CNPA7H and Acala 90 cultivars (respectively, without tricome, medium tricome density and high tricome density) were individualized and infested with 15 third/fourth instar nymphs of A. gossypii, and then first-instar nymphs of O. insidiosus were released on the plants. The evaluations were made daily, quantifying survival and nymphal development; the number of cotton aphids A. gossypii per day and total; the number of eggs and the population of the predator (number of insects by female); and the conversion efficiency of A. gossypii predaceous. The nymphal development did not differ according to the cotton cultivars. The Antares cultivar favored a higher daily predation rate for the 1st, 2nd and 4th instars and adults of O. insidiosus. The number of eggs and nymphs was smaller when O. insidiosus females were confined on the Acala 90 cultivar. According to the predation rate of O. insidiosus, the efficiency of alimentary conversion was determined for the Antares, CNPA7H and Acala 90 cultivars, being respectively, 4.28, 3.00 and 2.75 cotton aphid predation for each egg of the predator.
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The life table parameters were studied for Orius insidiosus on the three cotton plant cultivars Antares, CNPA7H and Acala 90 (respectively, without tricome, medium tricome density and high tricome density). This study showed that the type of cultivar can strongly influence the life-table parameters. The intrinsic rate (rm) was 0.088 (on Antares), 0.081 (CNPA7H) and 0.079 (on Acala 90), which was expected as these differences were also observed for development time, survival, fecundity and longevity on the cultivars. The reproductive rate (Ro) was 18.53 on the Antares cultivar, but showed less difference for CNPA7H (12.26) and Acala 90 (12.95). The development time was 33.9, 30.62 and 32.13 days for Antares, CNPA7H and Acala 90, respectively. The age-specific survival was similar until the 12th day. Maximum survival was 60 days on the Antares cultivar. Females usually began to oviposit after 16 days on the Antares cultivar and the after 19 days day on CNPA7H and Acala 90.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The post-larval development of the mud crab Eurytium limosum was studied under laboratory conditions by using the offspring of ovigerous females collected at the Comprido River mangrove, SP, Brazil. The first crab stage is fully described and the juvenile development, until crab stage 10, is examined with emphasis on morphological change, sexual differentiation and growth patterns. The carapace of the first crab stage is nearly square as observed in other xanthids, becoming similar to adults only at stage 15. The sexes can be distinguished from stage four, based on the number of pleopods and their morphology. While the intermoult period increases, the moult percentage decreases at each stage. The abdominal allometric growth is sex-dependent, with males showing a negative (b=0.71) and females an isometric (b=0.95) relative growth pattern. Male gonopods undergo a positive allometric growth, and their shape changes remarkably until sexual maturity. The cheliped dentition can be observed after stage 4. Regardless of sex, most crabs have a molariform right cheliped, which is thought to aid the handling of asymmetric prey such as gastropods.
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The size at onset of maturity of Eurytium limosum from a subtropical mangrove in Brazil was investigated. In this species, sexual maturity for males can be indicated by the allometric growth and gonopod length. For females, the morphological sexual maturity can only be externally verified through the relative quantity of setae along the abdominal margins and pleopods. Internally, gonad development was also examined. The size at which half of the population is physiologically mature was 11.6 mm of CW for females and 12.3 mm of CW for males. The values for the morphological and physiological maturity are very similar, indicating that the development of the secondary sexual characters is synchronized with the achievement of the physiological maturity for E. limosum.
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This study analyses the ontogenetic diet shifts of a Neotropical catfish, Pimelodus maculatus ( Siluriformes, Pimelodidae), from an ecomorphological standpoint. We collected 241 individuals in the Piracicaba River ( Brazil) and, in the laboratory, seven morphometric variables were recorded from each specimen: standard length (SL), body depth, head length, snout length, eye diameter, mouth height and mouth width. After standardizing these measurements ( as a proportion of SL), linear regressions were run to determine whether their growth was isometric or allometric in relation to SL. The diet analysis shows that the main food item for fish in the smaller size classes is aquatic insects, while the largest individuals feed mainly on other fish. As the great majority of the morphometric variables analyzed showed isometric growth as a function of SL - which means that these fish do not change their shape significantly during their lives - the ontogenetic diet shifts may be seen as a consequence of the absolute size increment of their mouth gape, which allows individuals to maximize their energetic gain by ingesting larger prey with a higher caloric content.
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The influence of a substratum-disturbing forager, the spotted goatfish Pseudupeneus maculatus on the assemblage of its escorting, opportunistic-feeding fishes was examined at Fernando de Noronha Archipelago (tropical west Atlantic). Followers attracted to spotted goatfish foraging singly differed from followers of spotted goatfish foraging in groups in several characteristics. The larger the nuclear fish group, the greater the species richness and number of individuals of followers. Moreover, groups of foraging spotted goatfish attracted herbivores, not recorded for spotted goatfish foraging singly. The size of follower individuals increased with the size and the number of foraging spotted goatfish. The zoobenthivorous habits of the spotted goatfish and its ability to disturb a variety of soft substrata render it an important nuclear fish for several follower species of the reef fish assemblage at Fernando de Noronha. (c) 2006 the Authors Journal compilation (c) 2006 the Fisheries Society of the British Isles.