Digital Microscopy was employed to characterize the microstructure of fiber-reinforced composite tubes manufactured by filament winding. Optical Microscopy was used for void characterization while Scanning Electron Microscopy was used for fiber and layer analysis. Acquired images were assembled in mosaics to reveal the microstructure of different cross-sections of the sample. Image processing was employed to detect either voids or individual fibers and measure their size, shape and spatial distribution. Void spatial distribution was analyzed with two different methods - local analysis and the tessellation method - revealing different behaviors along different cross-sections. Fiber layers were automatically detected and their average winding angle and dispersion were analyzed.

The influence of the fiber used as reinforcement in resin matrix composite materials submitted to repeated low energy impacts is analyzed. The aramid, glass and carbon fiber composites were submitted to drop weight tests from 0.5m and from 1m. The number of impact events necessary to cause failure was recorded, and the fracture characteristics of each composite were analyzed by optical microscopy and X-rays radiography. The results obtained showed that carbon fiber composites have better performance than the glass and aramid composites. This behavior was partially attributed to the higher elastic energy absorption of carbon fibers that delays the propagation of delamination, and fiber breakage. The failure mode of glass fiber composites was dominated by the higher number of glass fibers per surface area of the composites. The worst behavior shown by aramid composites was attributed to the intrinsic anisotropy of aramid fibers.

Vinte e sete espécies de dípteros caliptrados (Muscidae e Sarcophagidae) foram capturados no período de dezembro de 1993 a novembro de 1994, com armadilhas orientadas pelo vento (W.O.T.) contendo isca de fígado em putrefação, no jardim zoológico da cidade do Rio de Janeiro. As espécies capturadas em maior abundância foram Musca domestica (57,84%), Peckia chrysostoma (28,16%), Ophyra aenescens (17,11%), Oxysarcodexia thornax (17,82%), Synthesiomyia nudiseta (13,05%) e Oxysarcodexia diana (14,52%).

Twenty-seven species of calyptrate muscoids (Muscidae and Sarcophagidae) were collected from December 1993 to November 1994 with wind oriented traps (W.O.T.) baited with decomposing beef liver at the Rio de Janeiro Zoo. The most abundant species found were Musca domestica (57.84%), Peckia chrysostoma (28.16%), Ophyra aenescens (17.11%), Oxysarcodexia thornax (17.82%), Synthesiomyia nudiseta (13.05%), and Oxysarcodexia diana (14.52%).

Estudou-se a aderência de um modelo determinístico de isotermas para avaliar a dinâmica populacional de Synthesiomyia nudiseta (Diptera, Muscidae). As formas lineares das equações obtidas para os experimentos nas diversas fases foram: para ovo: 1/D = -0,18 + 0,02 . T; larva: 1/D = - 0,028 + 0,01 . T; pupa: 1/D = -0,069 + 0,01 . T; e adulto: 1/D = -0,4178 + 0,02 . T. Em função da temperatura, S. nudiseta pode apresentar de 4,18 a 8,95 e de 4,91 a 8,99 gerações por ano, quando calculadas por meio das equações de desenvolvimento e pelas simulações, respectivamente. Sendo que, quanto mais alta a temperatura, maior o número de gerações. Por intermédio da análise de variância verificou-se a significância para as equações de regressão relativas ao número de gerações anuais (Ng/ano) de S. nudiseta em função das isotermas, para duas situações estudadas. Obteve-se uma significância de 0,1%. As equações de regressão obtidas para essas situações foram: Ng/ano = 5,4 + 0,5 . T e Ng/ano = 5,1 + 0,52 . T. O número de gerações de S. nudiseta varia linearmente com as isotermas. Além disso, o número de gerações anuais para cada isoterma não difere estatisticamente quando calculadas por meio das equações de desenvolvimento ou por meio das simulações. Tais condições sugerem a adequação do modelo determinístico adotado.

The isothermal deterministic model adherence was studied to evaluate the population dinamic of Synthesiomyia nudiseta (Diptera, Muscidae). The linear form of equation obtained for the experiments in the several phases, were for Egg: 1/D = -0.18 + 0.02 . T; Larva: 1/D = -0.028 + 0.01. T; Pupa: 1/D = -0.069 + 0.01 . T; and Adult: 1/D = -0.4178 + 0.02 . T. In function of temperature, S. nudiseta can present from 4.18 to 8.95 and from 4.91 to 8.99 generations per year, when calculated through the equations of development and through the simulations, respectively. And the higher the temperature the larger the generation number. Through variance analysis it was verified the significance for the regression equations in relation to the annual generation number (Ng/year) of S. nudiseta in function of the isothermals, for two studied situations. It was obtained a significance of 0,1%. The regression equations obtained for these situations were: Ng/year = 5.4 + 0.5 . T and Ng/year = 5.1 + 0.52 . T. The number of generations of S. nudiseta varies linearly with the isothermal. Besides that, the number of annual generations for each isothermal does not differ statistically when calculated through the development equations or through the simulations. Such conditions suggest the adaptation of the deterministic model adopted.

Foram calculadas a extensão e sobreposição de nichos tróficos de dípteros caliptrados, criados em variados ambientes do Rio de Janeiro (área rural, urbana e florestal), utilizando-se diferentes substratos de criação (banana amassada, carcaça de camundongo, peixe (sardinha), fígado bovino, camarão e fezes humanas frescas. Foram criadas 14.294 moscas, pertencentes às famílias Calliphoridae, Fanniidae, Muscidae e Sarcophagidae. As maiores sobreposições de nichos tróficos, entre as espécies, foram assim constatadas: área rural: Phaenicia cuprina versus Chrysomya megacephala; área urbana: Phaenicia eximia versus Sarcodexia innota e P. eximia versus Synthesiomyia nudiseta; área florestal: P. eximia versus Hemilucilia flavifacies. Na área rural, o nicho mais extenso foi o de Peckia chrysostoma; na área urbana, o de S. nudiseta e Musca domestica. Euboettcheria collusor e P. eximia, na floresta, foram as espécies com nichos tróficos mais amplos.

Niche breadth and niche overlap of flies were estimated. The flies were breeding in different environments in Rio de Janeiro (rural, urban and forest). It were used as a larvae substrate: banana mashed, mouse carcass, fish (sardine), bovine liver, shrimp and fresh human faeces. It were bred 14,294 flies, belonging to four families: Calliphoridae, Fanniidae, Muscidae and Sarcophagidae. The greater niche overlap values observed were: rural area: Phaenicia cuprina versus Chrysomya megacephala; urban area: Phaenicia eximia versus Sarcodexia innota e P. eximia versus Synthesiomyia nudiseta; forest area: P. eximia versus Hemilucilia flavifacies. The greater niche breadth recorded were: rural area: Peckia chrysostoma; urban area: S. nudiseta and Musca domestica; forest area: Euboettcheria collusor and P. eximia.