966 resultados para aging of the population


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This study evaluated the effect of environmental stimuli and selective pressures in different geographical areas along a latitudinal gradient, on the juvenile recruitment, population structure, and sex ratio of the speckled swimming crab Arenaeus cribrarius. Samples were collected monthly during 1 year in three locations along the Brazilian coast: Macaé, state of Rio de Janeiro (MAC, 22°47′ S, 41°45′ W); Ubatuba, São Paulo (UBA, 23°27′ S, 44°58′ W); and São Francisco do Sul, Santa Catarina (SFS, 26°08′ S, 48°34′ W). The specimens of A. cribrarius were identified, counted, sexed, and measured for maximum carapace width (CW). The largest juvenile found was in UBA (47.7 ± 1.36 mm); and the largest adult females and males in MAC (74.26 ± 0.93 and 77.04 ± 0.79 mm, respectively). Recruitment in MAC was continuous, whereas in UBA and SFS, recruitment showed seasonal characteristics. The sex ratio was skewed toward females only in UBA; in MAC and SFS, males and females were present in equal proportions. These results indicate that geographical variations can cause differences in the recruitment and population structure of A. cribrarius. These regional differences call attention to the necessity for improved management plans and control of shrimp fishing, which can affect population patterns such as juvenile recruitment, population structure and life history of the target species and species that are caught in bycatch from shrimping, such as the swimming crab A. cribrarius.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Objective: The purpose of this study was to assess the influence of conditioning methods and thermocycling on the bond strength between composite core and resin cement. Material and Methods: Eighty blocks (8x8x4 mm) were prepared with core build-up composite. The cementation surface was roughened with 120-grit carbide paper and the blocks were thermocycled (5,000 cycles, between 5 degrees C and 55 degrees C, with a 30 s dwell time in each bath). A layer of temporary luting agent was applied. After 24 h, the layer was removed, and the blocks were divided into five groups, according to surface treatment: (NT) No treatment (control); (SP) Grinding with 120-grit carbide paper; (AC) Etching with 37% phosphoric acid; (SC) Sandblasting with 30 mm SiO2 particles, silane application; (AO) Sandblasting with 50 mu m Al2O3 particles, silane application. Two composite blocks were cemented to each other (n=8) and sectioned into sticks. Half of the specimens from each block were immediately tested for microtensile bond strength (mu TBS), while the other half was subjected to storage for 6 months, thermocycling (12,000 cycles, between 5 degrees C and 55 degrees C, with a dwell time of 30 s in each bath) and mu TBS test in a mechanical testing machine. Bond strength data were analyzed by repeated measures two-way ANOVA and Tukey test (alpha=0.05). Results: The mu TBS was significantly affected by surface treatment (p=0.007) and thermocycling (p=0.000). Before aging, the SP group presented higher bond strength when compared to NT and AC groups, whereas all the other groups were statistically similar. After aging, all the groups were statistically similar. SP submitted to thermocycling showed lower bond strength than SP without thermocycling. Conclusion: Core composites should be roughened with a diamond bur before the luting process. Thermocycling tends to reduce the bond strength between composite and resin cement.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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A survey to determine population trends and entomopathogenic fungi associated with the red palm mite (RPM), Raoiella indica, was conducted in Trinidad, Antigua, St. Kitts and Nevis and Dominica. RPM population density was evaluated by sampling a total of ten coconut palms per site in Antigua, St. Kitts and Nevis, Dominica, and Trinidad (Manzanilla and Icacos). Mites from the four islands were either surface sterilized or left unsterilized before being cultured on Tap Water Agar (TWA). A total of 318 fungal colonies were retrieved. A further 96 mites from Dominica were kept on sterile moist filter paper in a humidity chamber and a further 85 colonies were isolated. Based on morphological observations of all 403 isolates, a sample consisting of 32 colonies (8 %) was sent for identification at CABI-UK. Of the 27 fungi positively identified, 15 isolates belonged to the genera Cladosporium, three to Simplicillium spp., and one to Penicillium. Other fungi genera with limited or no entomopathogenic potential included: Aspergillus, Cochliobolus, Fusarium, Pestalotiopsis and Pithomyces. The results show a potential use of entomopathogenic fungi for population management of the red palm mite in the Caribbean region.

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The aim of this study was to relate the presence of a temporal acoustic window (TAW) to the variables sex, age and race. This observational study was conducted in patients under etiologic investigation after stroke, sickle-cell anemia and hospitalization in an intensive therapy neurologic unit. TAW presence was confirmed by bilateral assessment by two neurologists via transcranial Doppler (TCD). Multiple logistic regression was performed to explain the presence of the window as a function of sex, age and race. In 20% of the 262 patients evaluated, a TAW was not present. The incidence of TAW presence was greater in men (odds ratio [OR] = 5.4, 95% confidence interval [CI] = 2.5-11.7, p < 0.01); lower with increased age (OR = 0.9, 95% CI = 0.92-0.97, p < 0.01); and lower among those of African and Asian descent (OR = 0.32, 95% CI = 0.14-0.70, p = 0.005). On the basis of the results, more men than women had TAWs, and the decrease in TAWs was associated with increased age and African or Asian descent.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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The skin aging is a matter of discomfort verified in the population. Thus, every day, new products are launched on the market to offer different manners to prevent the premature aging of the skin. In this context, active substances, as alpha and beta hidroxyacids (AHA/BHA), beyond the sunscreens, are considered a way of prevention and amelioration of the effects caused in the skin due to the time. The aim of this study was to develop and evaluate a cosmetic cream containing AHA/BHA and sunscreen. It was studied in relation to its physical-chemical and microbiological characteristics. According to the results, the formulation developed present a shelf life of 758 days and the preservative system was effective. Considering the parameters evaluated, the cream probably would be commercially accepted.

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The skin aging is a matter of discomfort verified in the population. Thus, every day, new products are launched on the market to offer different manners to prevent the premature aging of the skin. In this context, active substances, as alpha and beta hidroxyacids (AHA/BHA), beyond the sunscreens, are considered a way of prevention and amelioration of the effects caused in the skin due to the time. The aim of this study was to develop and evaluate a cosmetic cream containing AHA/BHA and sunscreen. It was studied in relation to its physical-chemical and microbiological characteristics. According to the results, the formulation developed present a shelf life of 758 days and the preservative system was effective. Considering the parameters evaluated, the cream probably would be commercially accepted.

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Luciferid shrimps have short life spans and a rapid turnover of generations, engage in sequential spawning, and protect their eggs during incubation. This study investigates the ecology of Lucifer faxoni Borradaile, 1915 in the littoral zone, Ubatuba region, São Paulo. Sampling was conducted monthly from July 2005 to December 2006 using a Renfro net trawled over a distance of 50 m for a total sampling effort of 50 m² at each station. Nine stations were sampled, ranging from 1 to 15 m deep. Three stations each were grouped into zones 1, 2 and 3 (Z1, Z2 and Z3). Monthly values of salinity, temperature and rainfall were recorded at each station. The pre-buccal somite length (SL) of each specimen was measured. The results showed that in shallower zones (Z1 and Z2), 6306 individuals were captured, whereas in the deeper zone (Z3), 3808 specimens were captured, but no significant differences in SL was detected between the specimens from Z1 and Z2 and those from Z3 (ANOVA, p=0.25). The abundance of shrimps did not differ significantly between seasons (Tukey’s test, p=0.02) except in the spring. The sex ratio differed significantly over the seasons (χ², p<0.05). The results were closely associated with environmental factors with respect to the spatial and seasonal distribution of L. faxoni. Rainfall affected salinity directly, and contributed to the displacement of these shrimps to deeper areas.

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Background: The objective of this study was to evaluate the consistency, coherence, and interobserver reliability of the Portuguese version of the Scandinavian Stroke Scale (SSS) in a multicultural population of stroke. Methods: The SSS was translated, culturally adapted, and applied by two independent investigators. This was a randomized transverse study involving two groups: group 1 included 20 patients in the acute phase and group 2 included 20 patients in the subacute phase after stroke was confirmed by computed tomography with a pre-stroke modified Rankin Scale score of 0. Each patient also underwent National Institutes of Health Stroke Scale (NIHSS) evaluation at hospital entry and at the time of the SSS evaluation for correlation with our current standard hospital practice. Consistency and coherence were analyzed by Cronbach’s α and interobserver reliability by ĸ. Results: Forty patients were evaluated with 0.88 consistency and coherence in both stroke phases. Mean interobserver ĸ was 0.76, with reliability considered excellent and good for most scale items, and moderate for only the facial palsy item. Conclusion: The SSS is adequate and validated to study post-stroke patients in a multicultural Brazilian population and in the Portuguese language.

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Adult specimens of the spot. Leiostomus xanthurus, were collected from bayou, Mississippi Sound, and barrier island locations along the Gulf Coast of Mississippi from November 1982 to July 1989. 7he mean total length of all spot sampled in comparable gill net sets was 219 mm (± 14 standard deviation, n=4,338). Ninety-five percent of the spot were collected in the island and sound areas, where the salinity was higher than in the bayous. Catch per unit effort was high at island and sound stations in spring and autumn, with relatively few fish caught during the winter spawning season and summer. The relatively high frequency of spot observed at the island stations in the autumn was probably influenced by spawning migrations, and the high spring values may represent a combination of two abundant year classes. The two greatest yearly collections, in 1983 and 1986, may have been influenced by sampling conditions or by environmental conditions favorable to survival either during those years or earlier when those fish were postlarvae. The smallest yearly catch occurred in 1985 and may have reflected the harsh weather conditions that year.

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The `Critically Endangered` Cone-billed Tanager Conothraupis mesoleuca was described in 71 93 9, based on a single specimen collected in the state of Mato Grosso, western Brazil. Not seen again in the wild until 2003, this poorly-known species was rediscovered in Emas National Park, in the Brazilian state of Goias. We describe here the discovery of a new population of Cone-billed Tanager in Chapada dos Parecis, along the upper Juruena River basin, in the state of Mato Grosso. The birds were always detected in (or near) flooded habitats along rivers. At least 40 individuals were found, but the population may be larger since areas of potential habitat are available in the upper Juruena basin and these have not yet been surveyed. We also provide here the first information on the biology and behaviour of the species based on observations in Juruena and Emas, as well as a first description of the female. Historical documents and our records support our suggestion that ""Juruena"", i.e. the type locality of the Cone-billed Tanager, refers to the Juruena telegraph station (12 degrees 50`S, 58 degrees 55`W). Considering that the range of the species is being settled, research on different aspects of its biology are urgent.