81 resultados para Patterns of conduct


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The profiles of high-performance gel filtration of venoms from Polybia paulista, Polybia ignobilis and Polybia occidentalis occidentalis showed 13 peaks distributed among the three species. These profiles presented similarities that permitted the chromatographic characterization of the genus Polybia and differences that permitted the identification of each species studied. Thus, the comparative analysis of chromatographic profiles of high-performance gel filtration of venoms may be used as an auxiliary tool in taxonomic studies of Polybia wasps.

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Objective: To examine the basis for local wall motion abnormalities commonly seen in patients with ischemic heart disease, computer-controlled isolated muscle studies were carried out. Methods: Force patterns of physiologically sequenced contractions (PSCs) from rat left ventricular muscle preparations under well-oxygenated conditions and during periods of hypoxia and reoxygenation were recorded and stored in a computer. Force patterns of hypoxic-reoxygenating and oxygenated myocardium were applied to oxygenated and hypoxic-reoxygenating myocardium, respectively. Results: Observed patterns of shortening and lengthening closely resemble those obtained from ischemic and non-ischemic myocardial segments using ultrasonic crystals in intact dog hearts during coronary occlusion and reperfusion, and are similar to findings reported in angiographic studies of humans with coronary artery disease. Conclusion: The current study, demonstrating motions of oxygenated isolated muscle preparations which are similar to those in perfused segments of intact hearts with regional ischemia, supports the concept that the multiple motions of both ischemic and non-ischemic segments seen in regional myocardial disease can be explained by interactions of strongly and weakly contracting muscle during the physiologic cardiac cycle.

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This paper describes the frequency of occurrence and reproductive patterns of the tree mangrove crab Aratus pisonii. Monthly samples were taken from January 1993 to June 1994 in an estuarine mangrove from Ubatuba region, Brazil. A total of 1 078 animals, 489 males and 589 females (131 ovigerous females) were collected. Carapace width ranged from 4.2 to 25.9 mm. A summer reproductive peak followed by a recruitment juvenile pulse was verified. Females were more abundant than males in the intermediate size classes. The sex-ratio in several months was biased towards females, suggesting a poligynous population and migration of females to mangrove fringes at the time of incubation and spawning.

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Several serological methods have been used for the characterization and identification of soybean bradyrhizobia. However, some problem were non-reactivity of certain strains and cross-reactivity among others. Since lipopolysaccharide (LPS) can often be used in strain identification, the objective was to investigate the antigenic properties and polyacrylamide gel electrophoretic pattern of 12 Brazilian strains of Bradyrhizobium japonicum that nodulate soybean and to compare them to standard strains. The close correlation between the LPS patterns obtained by SDS-PAGE and the serological analysis permitted us to assign the strains to nine groups different or the same as the standard strains.

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The present work analyzed spermatogenesis in two species of triatomines (genus Panstrongylus) using silver-ion impregnation. The sex chromosomes of P. megistus and P. herreri had nucleolar organizing activity and became strongly impregnated during the phases of meiotic prophase I. Fragmentation of the nucleolus occurred in both species during the meiotic cycle. The nucleolar region could be observed up to diakinesis in meiotic prophase after which only nucleolar bodies and fragments were seen. Postmeiotic reactivation of rRNA synthesis occurred in these two species and was probably related to cell differentiation.

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A taxonomic survey on fungus-growing ants (Attini) was made at 14 beaches on Santa Catarina Island (SC), Brazil. The samplings were manual, in soil or litterfall, in the following habitats: sandy beach, herbaceous vegetation and shrubby vegetation. From 12 species of Attini (ten of Acromyrmex Mayr and two of Cyphomyrmex Mayr), the most frequent were Cyphomyrmex morschi Emery and Acromyrmex crassispinus Forel, collected, respectively, on eight and ten of the monitored beaches. Altogether, Sorensen's similarity coefficients were high (range: 0.59-0.80), in spite of the lower numbers of ant species on sandy beaches.

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Fifty two colonies of Coptotermes havilandi were set up under laboratory conditions using alates collected from an urban area during a period of swarming. The first artificial nest used for each royal couple was a 6cm diameter Petri dish (22ml) filled with a moistened matrix of decayed pine sawdust. After 6 months, these colonies were transferred to 250ml plastic containers with the same culturing matrix. After 24 months a census of all colonies was performed. Each young colony had a live royal pair and the population size of all colonies indicated a nonlinear development. The total population (workers + soldiers + immatures + reproductives) of these incipient colonies ranged from 64 to 1, 164, with a mean of 345 individuals. The number of workers ranged from 53 to 830 individuals, and the number of soldiers ranged from 6 to 83. The present data showed a higher population of incipient colonies than our previous record for the species. We also compared the development of 12 transferred colonies to that of 12 untransferred incipient colonies. The results showed a higher population in transferred colonies, but in both incipient colonies (transferred and untransferred) there was a wide variation in total population. The correlation between queen weight and population size was positive in all 24 colonies.

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This study describes, for the first time, the occurrence of two patterns of honey storage in nests of the paper wasp Polistes simillimus. During the period of January of 1997 to September of 2000 we visited 262 colonies of P. simillimus, found at several places in States of São Paulo and Minas Gerais, in the southeast region of Brazil. Only in 2.67% of the colonies of P. simillimus searched presented the behavior of honey storage. Two of these colonies were in the pre-emergency phase, two in the post-emergency and three in decline. The results suggest that the honey storage can be correlated with the number of present individuals in the colony, because the colonies in decline, with larger number of individuals, presented many more cells occupied with honey than the nests in pre and post-emergency. There was not a pattern for the distribution of the cells with honey in the nests in decline. The honey storage in the colonies in pre and post-emergency of P. simillimus, suggests a strategy to increase success of foraging activity in the function of parental care. Already for the colonies in decline, this strategy seems to be associated with the individuals' survival in the aggregation, since the wasps are awaiting the passage of the unfavorable climatic conditions for the dispersion and foundation of new colonies.

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The cocoon, produced by most holometabolous insects, is built with silk that is usually produced by the larval salivary gland. Although this silk has been widely studied in the Lepidoptera, its composition and macromolecular arrangement remains unknown in the Hymenoptera. The macromolecular array patterns of the silk in the larval salivary gland of some meliponids, wasps, and ants were analyzed with polarized-light microscopy, and they were compared with those of Bombyx mori (Lepidoptera). There is a birefringent secretion in the glandular lumen of all larvae, due to filamentous structural proteins that display anisotropy. The silk in the distal, middle and proximal regions of the secretory portion of Formicidae and Vespidae glands presented a lattice optical pattern. We found a different pattern in the middle secretory portion of the Meliponini, with a zigzag rather than a lattice pattern. This indicates that the biopolymer fibers begin their macromolecular reorganization at this glandular region, different from the Formicidae and the Vespidae, in which the zigzag optical pattern was only found at the lateral duct. Probably, the mechanism of silk production in the Hymenoptera is a characteristic inherited from a common ancestor of Vespoidea and Sphecoidea; the alterations in the pattern observed in the Meliponini could be a derived characteristic in the Hymenoptera. We found no similarity in the macromolecular reorganization patterns of the silk between the Hymenoptera species and the silkworm.

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We used light and transmission electron microscopy to examine the morphology of the accessory glands of immature and mature adult males of Apis mellifera L. We also made an electrophoretic analysis of the protein content of the mature gland. The glands of the immature male actively secrete a mucous substance that can be seen in the lumen of the gland of the mature male. This secretion stains with mercury bromophenol blue and with periodic acid-Schiff reaction, which stain glyconjugates. The protein content was higher in the lumen secretion than in the gland wall extracts. The electrophoresis patterns of the wall extracts were different from those of the secretion found in the gland lumen.

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We assessed how the abundance of ant-tended Hemiptera associated with two Amazonian myrmecophytes, Tococa bullifera and Maieta guianensis, varied as a function of resident ant species. We collected five species or morpho-species of adult hemiptera in the domatia of M. guianensis, with four of these species also found in Tococa bullifera. Maieta guianensis plants inhabited by Crematogaster laevis had over four-fold more hemiptera in them than plants inhabited by Pheidole minutula. In contrast, the density of hemiptera in Tococa bullifera domatia was independent of the species of ant resident. For each of the two ant species inhabiting Maieta guianensis, there was a positive and significant relationship between the abundance of hemiptera and workers inhabiting a plant. This relationship was also significant and positive for the Tococa bullifera plants inhabited by C. laevis. However, there was no relationship between Azteca worker and hemipteran density, although there was a trend towards a positive relationship. Our results indicate that hemipteran abundance can vary significantly between different myrmecophyte species, but that the nature of this relationship is mediated by the identity of the ant associate. Because hemipterans are herbivores, the costs and benefits of different ant partners to the host plant may vary in ways that are often overlooked.

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Coptotermes gestroi and Heterotermes tenuis (Isoptera: Rbinotermitidae) are important pests in southeastern Brazil causing serious economic damage. In this study we determined the demographic patterns and foraging activity of these species using mark-release-recapture and the consumption of wooden stakes. Using both the weighted mean and Lincoln index methods, population estimates ranged from ≈ 0.57 to 1.99 million individuals for C. gestroi and from ≈ 0.20 to 1.37 million for H. tenuis. Territory size of the colonies ranged from 172.5 to 5235 m 2 for C. gestroi and from 16 to 40 m 2 for H. tenuis. Our results also indicate that foraging activity was dependent on the minimum temperature; however, the existence of a compensation strategy in the foraging activities may permit foragers to exploit food sources under different environmental conditions.

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Captive brown brocket deer (Mazama gouazoubira) were manually restrained to assess tear production by the Schirmer tear test I to measure intraocular pressure by applanation tonometry, to examine ocular conjunctival epithelial cells via cytologic and histologic samples, and to survey ocular conjunctival microflora by microbiologic culture. The mean value for the Schirmer tear test I was 8.9 ± 1.8 mm/min, and the mean intraocular pressure was 15.3 ± 3.1 mm Hg. Conjunctival epithelium contained stratified pavimentous layers of cells, and the microflora consisted of predominantly gram-positive bacteria. Copyright 2007 by American Association of Zoo Veterinarians.

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The aim of this paper is to verify the correlation between environmental indicators and behaviors expressed by laying hens kept in cages. The birds react to a severe environment through their behaviors, end the behaviors can be monitored to identify the birds' welfare conditions. The behaviors birds display ere the result of stress caused by the combination of environmental temperature, relative humidity, radiant heat, and air speed (environmental temperature being the most important). In order to check the influence of the environment, an experiment was carried out on a commercial poultry farm, located in the city of Bastos. The study was initiated in March 2007, during four non-consecutive weeks. The birds' behaviors were recorded using video, by cameras installed in the cages. The birds behaviors were identified and noted for the frequency of occurrence for each bird, and the average duration of each behavior (in seconds), using video samples of 15 minutes recorded from 1 PM to 4 PM. The environmental variables collected were: air temperature, concentration of ammonia, relative air humidity, velocity of the air, noise, roof temperature, and light intensity. The observed behaviors were: opening wings, stretching, threatening, ruffling feathers, drinking water, aggressive pecking, eating, running, lying down, stretching head out of the cage, preening, mounting and prostrating. Principal Components Analysis was used to determine associations between the behavior variables and environmental variables described above. In this experiment, there were no significant correlations between behavioral variables and environmental variables.