Structural and morphological characteristics of (Pb1-x Sr (x) )TiO3 powders obtained by polymeric precursor method

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Structural transition on Pb1-xSrxTiO3 produced by chemical method

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Tunable visible photoluminescence of powdered silica glass

intense photoluminescence in the visible region was observed at room temperature in standard soda-lime-silica glass powder, mechanically milled in a high-energy attrition mill. The emission band maximum shows an interesting dependence on the exciting wavelength, suggesting the possibility to tune the PL emission. These findings indicate that the photoluminescence may be directly related to unsatisfied chemical bonds correlated with the high surface area. The Raman scattering and ultraviolet-visible optical reflectance measurements corroborate this assertion. Transmission electron microscopy measurements indicate that samples milled more than 10 h present the formation of nanocrystallites with about 10-20 nm. (C) 2007 Elsevier B.V. All rights reserved.

Vibrational and Thermal Properties of Crystalline Topiramate

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Synthesis, optical and ferroelectric properties of PZT thin films: experimental and theoretical investigation

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Improvement of electrical properties of Sr-modified (Pb,Ca)TiO3 thin films grown by soft chemistry route

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

Effect of strontium addition on ferroelectric phase transition of PZT thin films prepared by chemical route

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

Avaliacão da satisfação do usuário e da qualidade dos tratamentos endodônticos em Centros de Especialidades Odontológicas da Grande Natal-RN

Objective: To evaluate the degree of users satisfaction and technical quality of endodontic treatment in specialized dental clinics (CEO) of Grande Natal / RN between 2006 and 2008. Methodology: evaluated 282 endodontically treated teeth in CEOs through clinical and radiographic examinations. A questionnaire about the clinical condition of the tooth, evaluation of care and satisfaction with treatment was applied. Data on pre-and trans-operative were noted by the patient's clinical record. Endodontically treated teeth were examined by a specialist in endodontics, which compared with previous radiographs and current ones. The collected datas were presented descriptively by absolute numbers, percentages, averages. To determine the association between the independent and dependent variables was carried out through the bivariate association test Chi-square and Fisher exact test. Results: 79.8% presented with radiographic normal and 84.4% without pain symptoms. 8.2% of the teeth were fractured and 3.2% extracted. The persistence of the periapical lesion was associated with initial periapical status (p <0.05). 91.5% of patients are satisfied with the outcome of treatment. Such satisfaction is associated with absence of pain and an adequate esthetic tooth position (p <0.05). Conclusion: endodontic treatment in specialized dental clinics have an adequate technical quality, resulting in the success of endodontic therapy performed in these centers and that users are satisfied with the treatment

Metal-insulator transition in Nd1-x Eu-x NiO3 probed by specific heat and anelastic measurements

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

Dinâmica de reprodução e comportamento reprodutivo de branchoneta Dendrocephalus brasiliensis Pesata, 1921 como incremento na produção de alimento vivo para peixes ornamentais

Reproductive behavior of Dendrocephalus brasiliensis Pesta, 1921(Crustacean: Anostracan). The reproductive behavior of fresh water Anostracan has been poorly investigated in carcinology specialized literature, specifically in relation to Dendrocephlaus brasiliensis Pesta, 1921, with abundant data just about the geographical distribution of that Anostracan. The objective of this work was to know the reproductive behavior of this Anostracan, in different seasons (dry and raine). For this, ripe individuals of both sexes were collected in four pond of the of Fish farming Station of Paulo Afonso (EPPA), through monthly captures in each ponds, from December 2004 to November 2005. The type of reproduction was observed after the placing in aquariums (a) of then with males and (b) other on individually, at the nauplii phase, where they stayed for 15 days until the reproductive age. The sexual proportion was calculated through the relative frequencies of males and females, every month, for the whole collection period during 10 days. the production of cysts was related to the size of the female. The male: female ratio in the study period was 1 male:1,07 female. The proportion male:female was from 48,25% : 51,75% along the year. Concerning the type of reproduction, it was observed that this specie is characteerized by sexual reproduction

Atividades comportamentais e comportamento alimentar de rã touro, Lithobates catesbeianus (Shaw, 1802), de pigmentação normal e albina em cativeiro

The behavior of bullfrogs reared in captivity must be well understood to support management practices that use efficient feeding regimes. In general, bullfrogs reared in captivity have normal pigmentation, but to develop an enhanced product, some studies have investigated the introduction of albino individuals in frog farms. The present study characterized the behavior of both pigmented and albino bullfrogs reared in captivity. In an initial experiment, 48 bullfrogs (70.5 ± 25.6 g) housed in small stalls were fed once a day at random times. Frogs were filmed and the images showed that both the pigmented and albino varieties behaved similarly: food intake was more frequent at dawn followed by light periods; moving and resting in dry areas may be associated to feeding events; frogs appeared to anticipate feeding time and to rest in the water more frequently in periods other than feeding time; daylight is the recommended period for feeding both pigmented and albino frogs. In a second experiment, 72 albino bullfrogs were fed at fixed times (10 a.m. or 4 p.m.) in small stalls. An initial weight of 23.8 ± 7.6 g was considered to evaluate frog performance, and after the animals reached 60.0 ± 20.0 g, they were filmed for behavior analyses. Food intake varied as a function of feeding time, and frogs were more likely to eat during the early hours of the day and immediately after receiving fresh food. Frogs fed only in the afternoon changed their behavior. Food supplied twice a day stimulated the albino frogs to eat at different times, but did not increase growth. Although fresh food stimulated feeding behavior, food intake was more frequent at dawn. Food supplied at this time of day should therefore be further investigated. The results did not indicate a more suitable feeding time (10 a.m. or 4 p.m.) for albino bullfrogs, or any advantage in using two feedings per day. The results provide xvi important information about bullfrogs in terms of food supply regime and activity preferences throughout the day. This novel information will contribute to future studies in this area

Influência da salinidade e temperatura da água nas respotas comportamental e fisiológica de camarões marinhos Litopenaeus vannamei(BOONE 1931)

The shrimp Litopenaeus vannamei has been grown in highly variable environments, especially in relation to salinity and water temperature. The adjustment to such conditions mainly involves changes in behavior, physiology, particularly in the immune response. This may consequently reduce the welfare of these animals. Despite the widespread farming of the species, little is known about their behavioral and physiological responses under stressful conditions. Thus, the objective of this study was to assess the influence of different salinities and temperatures in the behavior of the marine shrimp L. vannamei, and its relation to the total hemocytes count. In the laboratory, juvenile shrimp were kept in glass aquaria with a closed water recirculation system, continuous aeration and filtration, and under a 12:12 h light/dark cycle. Behavioral observations occurred 1, 4, 7 and 10 h after the start of each phase (light or dark). To assess the influence of salinity, shrimp were first acclimated and then observed at 2, 30 or 50 ppm salinity water, while temperatures tested were 18, 28 and 33 ° C. At the end of each experiment (30 days), shrimp hemolymph was collected for subsequent total hemocytes count (THC), a parameter used to assess stress. In general, feeding behavior was modified under lower salinity and temperature, with reduced values in feeding, exploration and digestive tract filling. Inactivity and burrowing were prevalent under extreme conditions water salinity and temperature, respectively: 2 and 50 ppm and 18 and 33 ° C; crawling was also less frequent under these conditions. In regards to light/dark cycle, shrimp were more active during the dark phase (crawling and swimming), while burrowing was higher during the light phase, regardless of salinity or temperature of the water. Inactivity behavior did not vary according to the light/dark cycle. Moreover, the total hemocytes count (THC) was reduced under 2 and 50 ppm salinity and 18 ° C temperature. Farming of L. vannamei under extremely low or high salinities and low temperatures is harmful. This suggests the species must be cultivated in salinities closer to those of the sea as well as at high temperatures, which seems to be ideal for a management focused on animal welfare, therefore, producing healthier shrimp

Oscilações Teta no hipocampo do rato durante tarefa de tomada de decisão espacial

The processing of spatial and episodic information during memory tasks depends on hippocampal theta oscillations. In the present study, I investigated the relationship between theta power and choice selection during spatial decision-making. I recorded local field potentials from the CA1 region of rats retrieving reward locations in a 4-arm maze. In trained but not in naïve animals, I observed a significant increase in theta power during decision-making, which could not be explained by changes in locomotion speed. Furthermore, a Bayesian decoder based on theta power predicted choice outcomes in speed-matched trials. The decoding time course revealed that performance increased above chance before the decision moment exclusively for theta power, remaining flat for other frequency bands. These results occurred for trained animals, but no significant prediction could be made for naïve animals. Altogether, the data support a mnemonic function of theta rhythm during spatial decision-making, indicating that these oscillations correlate with the retrieval of memories required for successful decisions

Comportamento do camarão de água doce macrobrachium rosenbergii (De Man, 1879) em cultivos misto e monossexo

Understanding the behavioral activities of freshwater shrimp in captivity is of paramount importance for the appropriate management of the species. In Brazil, the shrimp Macrobrachium rosenbergii is currently the most widely used species in the freshwater shrimp culture due to its high potential for cultivation and good market acceptance. Thus, the present study aimed to describe and characterize the behavioral activities of M. rosenbergii in monosex and in mixed (male and female) (manuscript 1, 2 and 3) populations and the growth performance of this species in restrictive feeding conditions and in different feeding management (manuscript 4 and 5, respectively) . Juvenile and adult shrimps were collected from ponds of the Aquaculture Station - Unidade Especializada em Ciências Agrárias - Universidade Federal do Rio Grande do Norte (UFRN), Macaíba/RN and then transferred to the Laboratório de Estudos do Comportamento do Camarão LECC (Laboratory for Shrimp Behavioral Studies) of the Universidade Federal do Rio Grande do Norte (UFRN). For each treatment , eight aquaria of 250 L (50 cm x 50 cm x 100 cm) were used in a closed recirculating water system with artificial lighting, constant aeration , continuous filtration through a biochemical and biological filter (canister filter), and fine sand as substrate . The water quality was monitored daily. The lab consisted of two rooms with artificial lighting system , controlled by a timer with dark / light cycle of 12:12 h . In manuscript 1, the behavioral categories of the species were presented through an ethogram, which described 31 behaviors, subdivided into general and agonistic behaviors. Manuscript 2 compared the behavioral profile of shrimps in male and in female monosex and mixed populations over 24 hours in laboratory. In three types (mixed, male monosex and female monosex) of populations during the light and dark phases of the 24 hour cycle, the shrimps showed higher occurrence of cleaning behavior. Manuscript 3 examined the influence of the color of the shelter on the frequency of its use and behavioral activities of shrimp in mixed, in male monosex and in female monosex populations over 24 hours. We observed that the shrimp M. rosenbergii burrow more frequently during the light phase in male monosex and mixed populations; they also tend to choose the black shelters. Female monosex populations tend to use red and orange shelters. In manuscript 4, we evaluated in laboratory the behavioral activities and growth performance of juvenile shrimps under food restriction. We observed that a mild food restriction may be used since there is no loss concerning the growth of the animals; feeding management on alternate days , compared to daily management can be financially productive both reducing labor costs and reducing the amount of feed used . Manuscript 5 evaluated the behavior of shrimps in monosex and in mixed populations, as well as the latency of reach the food according to feed offer (tray or food dispersal) . Our results indicate that animals adjust to both types of feed offer food dispersal as much as tray, but they spend more time to reach the feed when it is offered in trays (feeders). Comparing culture types (mixed, male monosex and female monosex), the latency to reach the food was lower for female monosex population. The data obtained in this study demonstrate the importance of identifying different pressures and environmental stimuli on the behavioral responses of this species. This knowledge would support management improvement to optimize the levels of animals‟ welfare, resulting in a better zootecnical performance