944 resultados para maturity stages


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O objetivo do presente estudo foi determinar o crescimento relativo e a maturidade sexual morfológica de Menippe nodifrons. As coletas foram realizadas na Praia Grande e Tenório, Ubatuba, São Paulo. Os caranguejos foram separados quanto ao sexo e mensurados na região da largura (LC) e comprimento da carapaça, comprimento e altura dos própodos quelares direito e esquerdo, largura do abdome (LA) nas fêmeas e comprimento do gonopódio (CG) nos machos. Obteve-se 399 indivíduos, sendo 195 machos e 204 fêmeas. Os machos atingiram a maturidade sexual com 29,7mm LC e as fêmeas com 31,6mm LC. Para as fêmeas a melhor relação que indicou a muda da puberdade foi LA vs. LC, sendo que o crescimento foi alométrico negativo na fase jovem e alométrico positivo após a muda da puberdade. Para os machos foi CG vs. LC evidenciando crescimento alométrico positivo na fase jovem e isométrico na fase adulta.

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The relative growth of the fiddler crab Uca cumulanta was studied, primarily to determine the size at the onset of sexual maturity for a mangrove population in the estuary of the Patitiba River, Paraty, Rio de Janeiro state, Brazil. The evaluation of the morphological sexual maturity of U. cumulanta was performed using the allometric technique. The relationships that most precisely indicated the size at onset of sexual maturity were carapace length (CL) vs propodus length for males and CL vs abdomen width for females. Males and females are mature at 5.25 and 4.75 mm CL, respectively. The remarkable ontogenetic changes observed in the allometric growth of the male major cheliped and the female abdomen, indicate that growth of these structures is closely connected to the timing of sexual maturity. The relative size at onset maturity obtained for this species was 0.68 and this index was compared to that seen in other species in the genus.

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The comparative study of the ultrastructure of the midgut epithelium of stingless bee larvae that eat plant protein (pollen) and animal protein (carrion) throughout the larval phase, shows variations in the digestive cells that are only relative to larval aging and not to the type of larval diet. The cells of older larvae present a cytoplasm with empty spaces that result from emptying of lipid and glycogen stocks, and the presence of autophagic vacuoles. These results are discussed in relation to the hypothesis that variations in the digestive tract of insects may be associated with different diets or phylogeny. We conclude that different diets do not determine cell morphology adaptations in the studied species. As the variations in the ultrastructure of the midgut epithelium are the same in all studied species, including the necrophagous species Trigona hypogea, throughout the larval stage, this sequence of changes seems to be due to different physiological state during larval development.

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This study describes the changes undergone by cells of the salivary glands of unfed and feeding (at day two and four post-attachment) Rhipicephalus sanguineus males, as well as new cell types. In unfed males, types I and II acini are observed with cells undifferentiated, undefined 1 and 2 (the latter, with atypical granules), a, c1 and c3; type III is composed of cells d and e; and type IV present cells g. In males at day two post-attachment, type I acini exhibit the same morphology of unfed individuals. An increase in size is observed in types II, III, and IV, as cells are filled with secretion granules. Some granules are still undergoing maturation. In type II acinus, cells a, b and c1-c8 are observed. Cells c7 and c8 are described for the first time. Cells c7 are termed as such due to the addition of polysaccharides in the composition of the secretion granules (in unfed individuals, they are termed undefined 1). Type III acini exhibit cells d and e completely filled with granules, and in type IV, cells g contain granules in several stages of maturation. In males at day four post-attachment, type I acini do not exhibit changes. Granular acini exhibit cells with fewer secretion granules, which are already mature. In type II acini, cells a, b, c1-c5 are present, type III exhibit cells d and e, and type IV contain cells g with little or no secretion. This study shows that in the salivary glands of R. sanguineus males, cells a, c1, and c3 of type II acinus, and cells d and e of type III do not exhibit changes in granular content, remaining continuously active during the entire feeding period. This indicates that during the intervals among feeding stages, gland cells reacquire the same characteristics found in unfed individuals, suggesting that they undergo reprogramming to be active in the next cycle.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Um total de 3518 espécimes (1607 machos e 1911 fêmeas) de Dipturus chilensis foi amostrado. Os machos tiveram comprimentos totais entre 44.0 e 99.0 cm e as fêmeas entre 45.0 e 110.0 cm. A composição de comprimentos totais das capturas agrupadas foi significativamente diferente entre ambos os sexos, sendo as fêmeas maiores do que os machos. A razão sexual favoreceu as fêmeas. O comprimento total em que 50% dos espécimes foram retidos pelo aparelho de pesca foi de 69.0 cm nos machos e de 73.0 cm nas fêmeas. Uma sub-amostra de 124 espécimes (48 machos e 76 fêmeas) foi analisada para avaliação dos parâmetros reprodutivos. Para os machos, o tamanho de 50% de maturidade resultou em 78.5 cm enquanto que para as fêmeas este parâmetro foi estimado em 81.4 cm. Observações preliminares sobre a descrição da cápsula ovígera são também fornecidas.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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P>The softnose skates Bathyraja brachyurops and Bathyraja macloviana represent an important portion of the skate catches of the Uruguayan trawling fleet in the southwestern Atlantic. From March to October 2004, specimens of these species were collected at 75-200 m depth range in the area situated between latitudes 37 degrees 00'-39 degrees 30'S. For B. brachyurops, total length at which 50% of the specimens were retained by the gear was 68.0 cm for both sexes; T(L50) was estimated at 65.4 cm for males and 67.0 cm for females. For B. macloviana, total length at which 50% of the specimens were retained was 56.0-57.0 cm for both sexes; T(L50) was estimated at 53.5 cm for males and 52.0 cm for females. Egg capsule length varied from 79-91 mm in B. brachyurops and 69-75.5 mm in B. macloviana. In both species, capsules displayed striated surfaces and similar gross morphology, although egg capsules of B. macloviana had more robust anterior horns and a smaller size than those of B. brachyurops. Egg capsules of the latter also exhibited microscopical prickles. Capsule edges were laterally keeled with a groove along the keel, and a straight and transverse velum was present in the egg capsules of both species.

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The sexual development of Atlantoraja platana from the south-west Atlantic Ocean was analysed. According to the reproductive variables considered for both sexes, males were found to mature at 620 mm and females at 715 mm total length. (c) 2008 The Authors Journal compilation (c) 2008 The Fisheries Society of the British Isles.

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The aim was to analyze the prevalence of the stages of behavior change (BCS) and the perceived barriers to physical activity in older people residents in a medium size city of São Paulo state, Brazil. Seventy-nine older people participated of the study. The BCS was assessed by the Questionnaire of Behavior Chance Stages and those on perception of barriers by the Questionnaire on Barriers to the Practice of Physical Activity in Older People (QBPPAE). Statistical analyses was comprised by the Chi-square test (p<0.05). Data showed that: a) 64,6% of the older people do not practice physical activity and only 22,8% of them have been practicing it on a regular basis for more than 6 months; b) The most perceived barriers were: "Active enough", "Too old"; "Need to rest" and; "Disease or injury"; c) The BCS seems modulate significantly the perception of barriers (p<0.05). We can conclude that: a) most of the older people are in the pre-contemplation, contemplation and preparation stages of the BCS, yet; b) gender influences almost nothing with perception of barriers and; c) the BCS interferes with the type of perceived barriers. Such conclusions support the suggestions that it is necessary to develop specific strategies for different stages of behavior change if it is to minimize the barriers. This may help to find the most effective way to change to more active lifestyle in the elderly.

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The decline in frontal cognitive functions contributes to alterations of gait and increases the risk of falls in patients with dementia, a category which included Alzheimer's disease (AD). The objective of the present study was to compare the gait parameters and the risk of falls among patients at different stages of AD, and to relate these variables with cognitive functions. This is a cross-sectional study with 23 patients with mild and moderate AD. The Clinical Dementia Rating was used to classify the dementia severity. The kinematic parameters of gait (cadence, stride length, and stride speed) were analyzed under two conditions: (a) single task (free gait) and (b) dual task (walking and counting down). The risk of falls was evaluated using the Timed Up-and-Go test. The frontal cognitive functions were evaluated using the Frontal Assessment Battery (FAB), the Clock Drawing Test (CDT) and the Symbol Search Subtest. The patients who were at the moderate stage suffered reduced performance in their stride length and stride speed in the single task and had made more counting errors in the dual task and still had a higher fall risk. Both the mild and the moderate patients exhibited significant decreases in stride length, stride speed and cadence in the dual task. Was detected a significant correlation between CDT, FAB, and stride speed in the dual task condition. We also found a significant correlation between subtest Similarities, FAB and cadence in the dual task condition. The dual task produced changes in the kinematic parameters of gait for the mild and moderate AD patients and the gait alterations are related to frontal cognitive functions, particularly executive functions.