122 resultados para paw preference


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Mosquito community composition in dynamic landscapes from the Atlantic Forest biome (Diptera, Culicidae). Considering that some species of Culicidae are vectors of pathogens, both the knowledge of the diversity of the mosquito fauna and how some environment factors influence in it, are important subjects. In order to address the composition of Culicidae species in a forest reserve in southern Atlantic Forest, we compared biotic and abiotic environmental determinants and how they were associated with the occurrence of species between sunset and sunrise. The level of conservation of the area was also considered. The investigation was carried out at Reserva Natural do Morro da Mina, in Antonina, state of Paraná, Brazil. We performed sixteen mosquito collections employing Shannon traps at three-hour intervals, from July 2008 to June 2009. The characterization of the area was determined using ecological indices of diversity, evenness, dominance and similarity. We compared the frequency of specimens with abiotic variables, i.e., temperature, relative humidity and pluviosity. Seven thousand four hundred ten mosquito females were captured. They belong to 48 species of 12 genera. The most abundant genera were Anopheles, Culex, Coquillettidia, Aedes and Runchomyia. Among the species, the most abundant was Anopheles cruzii, the primary vector of Plasmodium spp. in the Atlantic Forest. Results of the analyses showed that the abiotic variables we tested did not influence the occurrence of species, although certain values suggested that there was an optimum range for the occurrence of culicid species. It was possible to detect the presence of species of Culicidae with different epidemiologic profiles and habitat preference.

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Nesting substrata, colony success and productivity of the wasp Mischocyttarus cassununga. Colonies of the wasp Mischocyttarus cassununga (von Ihering, 1903) are easily found in urban areas. However, in spite of the massive presence of this species in cities, little is known about its nesting habits, colony success and productivity. The present study aimed at answering the following questions: What are the substrates used for nesting by M. cassununga? What is the main foundation strategy adopted by M. cassununga in urban areas: a solitary female or associative foundation? Is there a relationship between foundation strategies and colony success? Is the total number of cells per nest related to the number of adults produced? The study was conducted in Juiz de Fora, southeastern Brazil, from December 2006 to November 2007. Nesting in man-made substrata seems to be a common strategy in M. cassununga (90.9%), with preference for nest building with a horizontal comb facing north. The colonies were established mainly by groups of foundresses (67.6%), with a success of 84%. The number of brood cells produced per nest was 71.74 ± 45.25 (18-203), and it was positively correlated with the number of adults produced. Hence, we can say that the nests founded by M. cassununga are located mainly in man-made substrata and mostly founded by a group of females. The cell reuse behavior increases the number of adults produced, as it optimizes foraging. These characteristics together with its behavior and nesting habits promote the success of this species in thriving in urban environments.

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Senescent stem-galls in trees of Eremanthus erythropappus as a resource for arboreal ants. Members of the dipteran families Tephritidae and Cecidomyiidae are inducers of stem-galls in Eremanthus erythropappus (DC.) MacLeish (Asteraceae), a tree common in the state of Minas Gerais, Brazil. When senescent, these galls become available to other organisms, such as ants. The present study describes a community of ants having benefitted from this process of ecosystem-engineering. The colonies in question inhabit the senescent stem-galls of trees of E. erythropappus and were examined in view of answering the following questions: i) whether the presence of stem-galls had any bearing on the richness, composition, or size of the ant colonies therein; and ii) whether the ants displayed any preferences regarding the shape and/or size of the galls. The study was conducted in populations of E. erythropappus trees near the city of Ouro Preto, MG. A total of 227 galls were collected, 14% of which were occupied by ants, belonging to eight different species. Half of the species occupied galls of both morphotypes (fusiform and globular), although we observed a marked preference for larger, globular shapes. Overall, our results showed the galls to be an effective and abundant resource, helping to maintain the diversity of the ants in the canopy. We also observed the occurrence of outstations and polydomic nests, although an in-depth examination of the influence of galls on this type of structuring has not been investigated.

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The objective of this work was to investigate heterosis and its components in 16 white grain maize populations presenting high quality protein. These populations were divided according to grain type in order to establish different heterosis groups. The crosses were carried out according to a partial diallel cross design among flint and dent populations. Seven agronomic traits were evaluated in three environments while four leaf diseases and incidence of corn stunt were evaluated in one. Least square procedure was applied to the normal equation X'Xbeta = X'Y, to estimate the model effects and their respective sum of squares. Among the heterosis components, in diallel analysis, significance for average heterosis in grain yield, number of days to female flowering and to all evaluated diseases was detected. Specific heterosis was significant for days to female flowering and resistance to Puccinia polysora. Results concerned to grain yield trait indicate that populations with superior performance in dent group, no matter what flint population group is used in crosses, tend to generate superior intervarietal hybrids. In decreasing order of preference, the dent type populations CMS 476, ZQP/B 103 and ZQP/B 101 and the flint type CMS 461, CMS 460, ZQP/B 104 and ZQP/B 102 are recommended to form composites.

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The objective of this work was to determine the potential of five species of Scelionidae wasps - Telenomus podisi, Trissolcus basalis, Trissolcus urichi, Trissolcus teretis and Trissolcus brochymenae - as natural enemies of the neotropical stink bug Dichelops melacanthus, and to determine if the presence of eggs of other stink bug species influences the parasitism and development of the parasitoids. Two kinds of experiments were done in laboratory: without choice of hosts (eggs of D. melacanthus) and with choice (eggs of D. melacanthus and of Euschistus heros). Biological parameters, including proportion of parasitism, immature survivorship, progeny sex ratio, immature stage development period, and host preference were recorded. All the evaluated parasitoids can parasitize and develop on D. melacanthus eggs. The first choice of eggs did not influence the proportion of D. melacanthus eggs parasitized by Tr. basalis, Tr. teretis or Tr. brochymenae. However, D. melacanthus eggs as the first choice of Te. podisi and Tr. urichi increased, respectively, 9 and 14 times the chance for parasitism on eggs of this species. Behavioral and ecological aspects of parasitoids should be considered prior to their use in biological control programs.

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The objective of this work was to evaluate the oviposition preference of Diatraea saccharalis and the effect of ten sugarcane cultivars on larval development. Oviposition preference was assessed under greenhouse conditions by three releases of couples of moths, with subsequent counting of egg masses and eggs per plant. In order to evaluate the effect of the cultivars on larval development, each plant was infected with about 150 eggs, and, 29 days later, the total number of internodes, number of bored internodes, number of life forms found, larval and pupal weight and length, and the width of larval head capsule were evaluated. The cultivars IACSP94-2101 and IACSP96-2042, the least preferred by D. saccharalis for oviposition, and IACSP94-2094, the most unfavorable for larvae entrance and development, show resistance to the pest.

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The objective of this work was to characterize the resistance of 50 cowpea (Vigna unguiculata) genotypes to Callosobruchus maculatus. A completely randomized design with five replicates per treatment (genotype) was used. No-choice tests were performed using the 50 cowpea genotypes to evaluate the preference for oviposition and the development of the weevil. The genotypes IT85 F-2687, MN05-841 B-49, MNC99-508-1, MNC99-510-8, TVu 1593, Canapuzinho-1-2, and Sanzi Sambili show non-preference-type resistance (oviposition and feeding). IT81 D-1045 Ereto and IT81 D-1045 Enramador exhibit antibiosis against C. maculatus and descend from resistant genitors, which grants them potential to be used in future crossings to obtain cowpea varieties with higher levels of resistance.

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The objective of this work was to evaluate bean genotypes for resistance to soybean looper (Chrysodeixis includens). Initially, free-choice tests were carried out with 59 genotypes, divided into three groups according to leaf color intensity (dark green, light green, and medium green), in order to evaluate oviposition preference. Subsequently, 12 genotypes with high potential for resistance were selected, as well as two susceptible commercial standards. With these genotypes, new tests were performed for oviposition in a greenhouse, besides tests for attractiveness and consumption under laboratory conditions (26±2ºC, 65±10% RH, and 14 h light: 10 h dark photophase). In the no-choice test with adults, in the greenhouse, the 'IAC Jabola', Arcelina 1, 'IAC Boreal', 'Flor de Mayo', and 'IAC Formoso' genotypes were the least oviposited, showing antixenosis-type resistance for oviposition. In the free-choice test with larvae, Arcelina 4, 'BRS Horizonte', 'Pérola', H96A102-1-1-1-52, 'IAC Boreal', 'IAC Harmonia', and 'IAC Formoso' were the less consumed genotypes, which indicates antixenosis to feeding. In the no-choice test, all genotypes (except for 'IAPAR 57') expressed moderate levels of antixenosis to feeding against C. includens larvae.

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Brazil is the world's largest producer of oranges and uses more than 70% of the harvested fruits in the production of juices. The amount of processed orange is growing about 10% per year, confirming the trend of the Brazilian citrus for juice production. This research aimed to investigate the Brazilian orange juice production chain from 2005 to 2009. Data from the amount of frozen juice produced and exported, international price of orange juice, and intermediate transactions were assessed in order to make possible selection of all interveners involved in the chain. The study using the Social Network Analysis (SNA) showed that the densest relationships in the network are from exporters to importers and from orange growers to the orange processing industry. No difference was found in the values of the network geodesic distance or the clustering coefficients from 2005 to 2009. The degree of centrality increased steadily throughout the years indicating that the processing industry attempts to minimize the risks by centralizing the actions. A decrease in export of orange juice from 2007 (2.07 10(6) t) to 2008 (2.05 10(6) t) was found, probably due to the world's financial crisis with recovery in 2009. Since 2004, there has been an increase of nearly 10% per year in the market preference of concentrate juice (OFCJ) when compared to the "not from concentrated" juice (NFC). Nowadays the NFC market represents nearly 50% of all Brazilian export which impacted in the logistic distribution and transportation issues.

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Harmonia axyridis was detected for the first time in Brazil in 2002. Since then, it has been recorded from the South to the Midwest of the country. Until now, almost all the registered cases were associated with the presence of aphids, its preferred source of food. Due to the occurrence of this species in areas of fruit growing in the South and Southeast of Brazil, the aim of this study was to analyze the preference and use of three different cultivars of fruit. The tests were set at 25ºC ± 1ºC, RH 70% ± 10%, and in a photophase of 12 h and with apples (Gala and Fuji), grapes (Niágara and Rubi), and pears (Williams and Asian). In the undamaged fruit experiment, the insects did not cause any noticeable damage. In the damaged and undamaged fruit experiment, a higher and statistically significant percentage of H. axyridis adults were found in the three damaged fruits. In the different cultivar experiment the Niágara grape, the Gala apple, and the Williams pear were significantly preferred by H. axyridis adults. These results may help in the management of this insect, preventing damage, which have been observed in other places where H. axyridis was introduced.

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ABSTRACT With the aim of identifying strategies to increase fruit consumption in Temuco, consumer segments were classified according to the importance and preference of theattributes type of fruit, package/ brand, benefit associated with fruit consumption and price. A survey was applied to 400 people in Temuco,Chile, distributed using a simple allocation: 200 working adults and 200university students. The questionnaire included the SWFL (Satisfaction with Food-related Life) scale, respondents’ fruit consumption habits and their characteristics. Using conjoint and cluster analyses, three segments were distinguished: Group 1 (22.0%) gave greatest importance to the package/brand and preferred themessage “prevents diseases” and “without information”; Group 2 (47.5%) gave greatest importance to the package/brand and preferred the message “prevents diseases”; Group 3 (30.5%) assigned greatest importance to the price and preferred the message “contains antioxidants”. The segments differed in their level of satisfaction with food-related life, self-declared lifestyle, age and presence of university students. The results provide input to promote fruit consumption in working adults and university students.

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This review discusses the present state of the art of the stereochemistry of electrochemical reactions. The extent of asymmetric induction is progressing, but in general diastereoselectivities and enantioselectivities remain behind those from chemical synthesis. In recent years, new methodological developments have been successful. Effects that play important roles in homogeneous chemistry have been used with success. Lack of expressive enantiomeric excess (ee) could be related to the absence of tightly organized structures during the reaction of interest. The highest ee might be expected for redox reactions where conformational preference in transition state plays the important role or for the ones performed while adsorbed on the electrode, and where the chiral element is also at the surface, either adsorbed or chemically bound to the surface and interacting directly with the substrate. Electroenzymatic synthesis has a promising future.

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Derivatives of N-tryptophyl-5-benzylidene-2,4-thiazolidinedione (7a-c) and N-tryptophyl-5-benzylidene-rhodanine (7d-f) were prepared by condensation of the intermediates 5 and 6 with different benzaldehydes, respectively. Their structural elucidation was carried through by IR, ¹H NMR and MS. The acute toxicity and antiedematogenic activity of the compounds 7b,c and 7e,f were evaluated. The data did not reveal any sign of toxicity, and no mortality was registered. As indomethacin (10 mg/kg; v.o.), the antiedematogenic activity of the compounds 7b (50 mg/kg; v.o.) and 7e, 7f (50 or 100 mg/kg; v.o.) against carrageenan-induced paw edema was verified at time intervals of 180 min.

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The perception of the flavor is an important attribute of quality in marine fish and other seafoods, being the first and main factor of discrimination for the evaluation, later acceptance and preference of the product by the consumer. Recently, the simple bromophenols have been considered an important group of key flavor compounds occurring in a wide variety of seafood species like fishes, mollusks, crustaceans and algae. When present in high concentration, in seafood, the bromophenols produce an undesirable flavor and are associated with inferior quality. Meanwhile, when present in low concentration levels (for example ng g-1) these compounds produce a desirable marine - or ocean-like - flavor and enhance the existing flavor in seafood. Indeed, simple bromophenols are widespread in seafood but virtually absent in freshwater fish. Herein we present a review on these flavor components found in the marine environment.

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Phenolic contents of extracts of Syzygium cumini leaves, collected monthly over a one-year period, were quantitatively determined by the modified Folin-Ciocalteau method. Extracts and tannin-free fractions were assayed by their potential to inhibit mouse paw edema induced by C48/80. HPLC showed high molecular weight phenolic species and flavonoids in the active extracts and fractions. The highest total phenolic content corresponded to the most potent degree of inhibition and the flavonoids were supposed to be the main species responsible for the activity, given that the flavonoid-enriched ethyl-acetate fraction maintained its effect down to a dose of 0.01 mg/kg in a dose-response manner.