Identificação de parâmetros elásticos e piezoelétricos em estruturas activas tipo placa : técnicas de optimização clássica versus redes neuronais artificiais

Neste trabalho são apresentados dois métodos não destrutivos para a identificação de parâmetros elásticos e piezoeléctricos em estruturas laminadas activas do tipo placa, com sensores/actuadores de superfície. O primeiro destes métodos resolve o problema inverso através de métodos de optimização clássica, minimizando a diferença entre frequências naturais experimentais e as fornecidas por um modelo de elementos finitos. O segundo método baseia-se na construção de um “meta-modelo” do problema inverso, recorrendo a Redes Neuronais Artificiais. Os dois métodos são comparados recorrendo a resultados experimentais de uma placa em vibração livre

Variation in quality of newly hatched chicks from Japanese breeder quail fed guava extract

The aim of this study was to evaluate the effects of guava extract as a dietary supplement for Japanese quail hens on incubation parameters, intestinal development, and the quality of newly hatched chicks. Six hundred and forty-eight eggs were collected from Japanese quail hens fed diets with 0.0, 3.0, 6.0, and 9.0 g/kg of guava extract. The study consisted of four treatments, six replicates, and 27 eggs per replicate. The guava extract contained 2% ellagic acid. The eggs were incubated at 37.5 °C and 65% relative air humidity. The hatch window, hatchability, embryo development in unhatched eggs, quality of newly hatched quails, and intestinal histomorphometry of a duodenum segment were evaluated. Differences among the treatments in hatchability and the hatch window were not significant. The guava extract did not affect mortality rate, live pecking, dead pecking, and contaminated and inverted eggs. The number of infertile eggs was lower in the groups that received 3.0 and 9.0 g/kg of extract in their diets. Use of up to 3.0 g/kg of guava extract in the diet increased the weight of both eggs and newly hatched chicks. The quality score of newly hatched quail was similar across treatments. The inclusion of 3.0 g/kg of guava extract in the diet of Japanese quail breeder hens increased the hatchling weight of the chicks and improved the villus to crypt ratio of their duodenum. Keywords: embryology, embryo metabolism, hatchery, incubation, breeder nutritio

The Temporal Pattern of Mating Behavior of the Fruit Fly, Anastrepha zenildae in the Laboratory

The state of Rio Grande do Norte is an important fruit-producing and exporting area in northeastern Brazil. The success of this industry depends on fruit fly population control, especially in fly-free exporting zones. However, many fruits are not exported because of quarantine restrictions imposed by importing countries. A survey in the state has detected a considerable increase of the fruit fly, Anastrepha zenildae Zucchi (Diptera: Tephritidae), probably a result of the introduction of irrigated guava orchards that make fruit available all year. Knowledge of the sexual behavior of Tephritidae has great importance to pest control programs, particularly those that employ the Sterile Insect Technique. In order to characterize the reproductive behavior of A. zenildae, 32 individuals (16 males; 16 females) in each of six generations were submitted to an artificial 12:12 L:D cycle (750: < 1 lux, lights on 07:00–19:00) and observed over their lifetimes. The courtship and copulation occurred in leks and the episodes varied with the time of day, courtship being most frequent between Zeitgeber time (ZT) 3 and ZT 7, peaking at ZT 5–6. Copulations occurred between ZT 2 and ZT 8, with a higher frequency between ZT 5–7 and a peak at ZT 6. Mean duration was 0.28 ± 0.03 min/male (range: 5–163 min). Males in the leks attempted to copulate mainly between ZT 3 and ZT 7 with a peak at ZT 6, and males outside leks peaked at ZT 7. The different timing of sexual behaviors among related sympatric species, including A. zenildae, may contribute to species isolation

Social roles and aging from a life-span perspective

Este trabalho investigou os papéis sociais e as tarefas evolutivas desempenhados por adultos. O local escolhido para investigação foi um assentamento de famílias de baixa renda do Distrito Federal criado em 1989. Utilizou-se um questionário contendo 17 questões abertas e 15 questões fechadas, preenchido pela primeira autora durante uma visita domiciliar. Participaram 98 respondentes (73 F e 25 M), sendo 51 entre 50 e 59 anos e 47 a partir de 60 anos. Os resultados apontaram que este grupo é heterogêneo e que seus papéis sociais são influenciados pelas variáveis demográficas (idade, sexo, escolaridade, ocupação, naturalidade e estado civil) e também pelas variáveis relativas à moradia atual. Concluiu-se também que as expectativas sociais, o suporte social e a escolarização são fatores de suma importância para oferecer recursos para a otimização e compensação necessárias a um envelhecimento bem sucedido. __________________________________________________________________________________________________________ ABSTRACTThis study investigated the social roles and developmental tasks of adults. The study took place in a settlement of low-income families, created in The Federal District in 1989. Data were collected through a questionnaire composed of 17 open and 15 closed questions, administered by the first author during a home visit. There were 98 respondents, 73 female and 25 male, being 51 between 50 to 59 years old and 47 elders above the age of 60. The result indicated that this group is heterogeneous and that its social roles are influenced by the demographic variables - age, sex, educational level, work, place of the birth and marital status, as well for the relative variables to current residence. The data allow the conclusion that social expectations, social support and the educational level are important resources for the optimization and necessary compensation to successful aging