Diversidade Ictiofaunística e Ecologia reprodutiva de uma espécie nativa de peixe da Bacia Piranhas-Assu, RN

The Caatinga biome is rich in endemic fish species fauna. The present study the results of fish faunal surveys conducted in the hydrographic basin of Piranhas-Assu of the Brazilian Caatinga biome. The fish samples collected were distributed in four orders (Characiformes, Perciformes, Siluriformes and Synbranchiformes), 11 families (Characidae, Curimatidae, Auchenipteridae, Anostomidae, Prochilodontidae, Erythrinidae, Cichlidae, Sciaenidae, Heptapteridae, Loricariidae, Synbranchidae) and 22 species, of which 17 are endemic and five have been introduced from other basins. The order Characiformes was the most representative in number of species (46,35% ) followed by Perciformes (35,38%), Siluriformes (17,44%) and Synbranchiformes (0,5%). The Nile tilapia, Oreochomis niloticus, the only exotic species, was most expressive in number of individuals (24.92%) followed by the native species piau preto, Leporinus piau (18,77 %). Considering the relative frequency of occurrence of the 22 species, 13 were constant, five were accessory and four were occasional. This study investigated the reproductive ecology of an endemic fish black piau, Leporinus piau from the Marechal Dutra reservoir, Acari, Rio Grande do Norte. Samplings were done on a monthly basis from January to December 2009, and a total of 211 specimens were captured. The environmental parameters such as rainfall, temperature, pH, electrical conductivity and dissolved oxygen of water were recorded. The sampled population showed a slight predominance of males (55%), however females were larger and heavier. Both sexes of L. piau showed positive allometric growth, indicating a higher increase of weight than length. The first sexual maturation of males occurred at smaller size, with 16.5 cm in total length than females (20.5 cm). During the reproductive period, the condition factor and gonadosomatic index (GSI) of L. piau were negatively correlated. This species has large oocytes with a high mean fecundity of 54.966 with synchronous oocyte development and total spawning

Diversidade Ictiofaunística e Ecologia reprodutiva de uma espécie nativa de peixe da Bacia Piranhas-Assu, RN

The Caatinga biome is rich in endemic fish species fauna. The present study the results of fish faunal surveys conducted in the hydrographic basin of Piranhas-Assu of the Brazilian Caatinga biome. The fish samples collected were distributed in four orders (Characiformes, Perciformes, Siluriformes and Synbranchiformes), 11 families (Characidae, Curimatidae, Auchenipteridae, Anostomidae, Prochilodontidae, Erythrinidae, Cichlidae, Sciaenidae, Heptapteridae, Loricariidae, Synbranchidae) and 22 species, of which 17 are endemic and five have been introduced from other basins. The order Characiformes was the most representative in number of species (46,35% ) followed by Perciformes (35,38%), Siluriformes (17,44%) and Synbranchiformes (0,5%). The Nile tilapia, Oreochomis niloticus, the only exotic species, was most expressive in number of individuals (24.92%) followed by the native species piau preto, Leporinus piau (18,77 %). Considering the relative frequency of occurrence of the 22 species, 13 were constant, five were accessory and four were occasional. This study investigated the reproductive ecology of an endemic fish black piau, Leporinus piau from the Marechal Dutra reservoir, Acari, Rio Grande do Norte. Samplings were done on a monthly basis from January to December 2009, and a total of 211 specimens were captured. The environmental parameters such as rainfall, temperature, pH, electrical conductivity and dissolved oxygen of water were recorded. The sampled population showed a slight predominance of males (55%), however females were larger and heavier. Both sexes of L. piau showed positive allometric growth, indicating a higher increase of weight than length. The first sexual maturation of males occurred at smaller size, with 16.5 cm in total length than females (20.5 cm). During the reproductive period, the condition factor and gonadosomatic index (GSI) of L. piau were negatively correlated. This species has large oocytes with a high mean fecundity of 54.966 with synchronous oocyte development and total spawning

Avaliação do banco de dissertações e teses da associação brasileira de antropologia: uma análise cienciométrica

VITULLO, Nadia Aurora Vanti. Avaliação do banco de dissertações e teses da Associação Brasileira de Antropologia: uma análise cienciométrica. 2001. 143 f. Dissertaçao (Mestrado) - Curso de Mestrado em Biblioteconomia e Ciência da Informação, Pontifícia Universidade Católica de Campinas, Campinas, 2001.

Biblioteca digital de teses e dissertaçoes: uma referência fundamental

OLIVEIRA, Raimundo Muniz de. Biblioteca digital de teses e dissertaçoes: uma referencia fundamental. In: CINFORM ENCONTRO NACIONAL DE ENSINO E PESQUISA DA INFORMAÇAO,HUMANISMO E DESENVOLVIMENTO CIENTIFICO E TECNOLOGICO,7.,2007,Salvador. Anais...Salvador:UFBA, 2007.Disponivel em:www.cinform.ufba.br>. Acesso em: 27 set. 2007. Acesso em: 27 set. 2010.

Bibblioteca Digital de Teses e Dissertações: uma estratégia de preservação digital

CUNHA, Jacqueline de Araújo. Biblioteca Digital de Teses e Dissertações: uma estratégia de preservação da memória científica. 2009. 141f. Dissertação (Mestrado)- Programa de Pós-Graduação em Ciência da Informação. Universidade Federal da Paraíba, João Pessoa, 2009.

Biblioteca Digital de Teses e Dissertações: grau de utilização pelos mestrandos do curso de Ciência da Informação das Universidades Públicas Brasileiras

A pesquisa aborda o uso das Tecnologias de Informação e Comunicação, que vem revolucionando as atividades e ocasionando muitas mudanças relacionadas ao acesso e uso de informações. O objetivo foi analisar o grau de utilização do conhecimento científico produzido pelos Programas de Pós-Graduação das Universidades Públicas Brasileiras, através da BDTD, pelos mestrandos dos referidos programas. Nos procedimentos metodológicos realizados, procurou-se inicialmente analisar o amplo espectro da população do corpus da pesquisa. Em razão da impossibilidade de trabalhar com os Programas de Pós-Graduação como um todo, optou-se por fazer um recorte, elegendo os cursos de Pós-Graduação em Ciência da Informação, vez que estes representam o principal segmento social de interesse da pesquisa. Foi utilizado o método de estudo de usuários, onde se optou por adotar o grupo, “estudos orientados aos usuários”, que identifica as necessidades e comportamento de acesso e uso da informação. Para coletar os dados, elaborou-se um questionário semi-estruturado com 25 questões, que versavam sobre o uso, dificuldades de acesso e recuperação da informação, bem como a satisfação na utilização dessa fonte informacional. Dentre os vários resultados obtidos, podemos destacar o fato de que a maioria dos mestrandos (71,8%) só teve contato com a BDTD somente no momento em que se encontrava cursando o mestrado e, somente 24,3%, tiveram contato durante a graduação. Estes resultados representam um problema, que pode afetar o bom desempenho do projeto BDTD, o qual consiste em disseminar e divulgar a produção científica dos Programas de Pós-Graduação das Universidades Públicas Brasileiras para a sua comunidade. Foi observado também, que os mestrandos oriundos do curso de Biblioteconomia tende a ter contato com a BDTD bem mais cedo do que mestrandos de outros cursos de graduação. A fim de minimizar o problema detectado, propõe-se uma divulgação mais eficaz na graduação através de dois procedimentos: Primeiro, o docente deve fazer uma divulgação mais eficaz da BDTD junto aos discentes de todos os cursos de graduação; segundo: deverá ser feita a divulgação na mídia eletrônica, através da inserção de ícones da BDTD, nos portais dos Departamentos dos Cursos de Graduação das Universidades Públicas Brasileiras. Acredita-se que com estes procedimentos seja possível aperfeiçoar o uso dessa fonte de informação científica.

Bibliotecas digitais de teses e dissertações brasileiras: paradigma do acesso livre à informação científica

A evolução da comunicação científica ao longo do tempo e o impacto causado pela A evolução da comunicação científica ao longo do tempo e o impacto causado pela A evolução da comunicação científica ao longo do tempo e o impacto causado pela se analisar as contribuições da Biblioteca Digital de Teses e Dissertações (BDTD)para a comunicação científica atual, destacando possibilidades emergentes e desafios a serem superados. Apresenta uma breve evolução da comunicação científica ao longo do tempo; discute os impactos causados pela Internet na comunicação, disponibilização e acessibilidade de informações técnico-científicas; e caracteriza BDTD destacando os desafios a serem superados. Dentre eles estão, a questão dos direitos autorais que ocasionam a baixa adesão dos autores ao projeto piloto do IBICT para disponibilizar teses e dissertações no meio eletrônico. Para este desafio, são apontadas sugestões.

Panorama brasileiro das bibliotecas digitais de teses e dissertações

As bibliotecas de teses e dissertações têm um papel fundamental para o desenvolvimento científico e cultural de um país. Nesse sentido, buscou-se, de modo geral, analisar o panorama brasileiro das bibliotecas digitais de teses e dissertações. Especificamente, objetivou-se caracterizar a sociedade da informação enquanto contexto das BDTD; caracterizar os vários tipos de bibliotecas surgidos a partir da inserção das novas tecnologias de informação e comunicação; identificar as diretrizes norteadoras da implantação de BDTD; e levantar as BDTD existentes no Brasil. Para tato, além de levantamento bibliográfico, realizou-se uma pesquisa nos sites de instituições de ensino superior brasileiras que já dispõe de bibliotecas digitais de teses e dissertações em funcionamento. A análise e interpretação destes dados nos permite considerar que no Brasil as BDTD encontram-se num estágio embrionário, sendo relevante pesquisar a histórica implantação e configuração desse novo modelo de biblioteca.

Investigação e avaliação da toxicidade aguda dos agrotóxicos mais utilizados no cinturão verde da Grande Natal (RN, Brasil) para o peixe-zebra (Danio rerio Hamilton Buchanan, 1822, Teleostei, Cyprinidae

The objectives of this research were to investigate the agrotoxic most used in the Gramorezinho region in the green belt of Natal, and to evaluate the acute toxicity of these, based on the LC50-48h values estimated in tests for Danio rerio, internationally used as test organism. The acute toxicity tests were performed under laboratory conditions, according to standardized methods (ABNT/NBR/15088/04) for this species. The LC50-48h estimated to Tamaron BR was 352.89 mg.L-1, which characterizes that as practically non-toxic, according to toxicological classes cited by Zucker. For Decis 25EC, the LC50-48h estimated was 0.0004156 mg.L-1 (4.156 X 10-4 mg.L-1), which classifies it as highly toxic to this species

Avaliação da toxicidade aguda do inseticida metomil e o seu efeito sobre a atividade da acetilcolinesterase do peixe Danio rerio

Methomyl (Lannate®) is an insecticide from the carbamate group, frequently used in pest control in various types of crops. This compound works inhibiting the activity of the enzyme acetylcholinesterase. The use of physicochemical and ecotoxicological analysis is the most efficient strategy for the correct characterization and control of residues of metomil. The main objectives of this study were to evaluate the acute toxicity of methomyl in 96 hours of exposure and, through a sublethal assay of 5 hours, to assess its effect on the activity of acetylcholinesterase present in brain and squeletic dorsal muscle of the Danio rerio fish. The results showed that the LC50-96 found to D. rerio was 3.4 mg/L and it was found through the average of four definitive tests. In vitro assays were used to test the inhibitory action of methomyl directly over soluble AChE, extracted from the squeletic dorsal muscle, with maximum inhibition of 68.57% to the insecticide concentrations of 0.2 mg/L. In sublethal tests with D. rerio, inhibitory effect of methomyl was found over the soluble form of AChE in the squeletic dorsal muscle, both in one and five hours of fish exposure to the insecticide. In both period, the average values of inhibition were around 61%. In the same condition, no significant inhibitory effect of methomyl soluble and membrane AChE of the D. rerio was observed in the 0.42, 0.85, 1.70 and 2.50 mg/L concentrations and in both times of fish exposure

Ecologia reprodutiva do peixe-donzela, Stegastes fuscus cuvier, 1830 (osteichthyes: pomacentridae) em arrecifes rochosos da praia de Búzios, Rio Grande do Norte, Brasil

The reproductive ecology of fish plays a key role both for rational exploitation methods and for protective measures of natural stocks. The purpose of this study was to analyze the reproductive aspects of the damsel-fish, Stegastes fuscus, during October 2004 to September 2005, in the coastal rocky reefs of Búzios Beach, Nísia Floresta, RN. Fish were captured using hooks and hand nets, during low tide. Reproduction was determined using sexual ratio, mean length of first maturation (L50), absolute fecundity and macroscopic characteristics of gonads. The following parameters were related to gonadosomatic index (GSI): condition factor (CF), hepatosomatic index (HSI), rain fall and temperature. In relation to sex distribution, it was observed that 78% were females and 22% were males. The L50 was 6.2 cm for females and 7.0 for males. Average fecundity was 6832 oocytes. Results showed that S. fuscus had better body condition in the months prior to spawning, particularly during initial and intermediate stages of maturation. Five stages of gonadal maturation were identified through macroscopic analysis: immature, in maturation, mature, spent and resting. The HSI was inversely related to the GSI. This was possibly due to the reproductive cycle of this species which was associated to the dry period of this region. During this period, low rain fall and high temperatures provide an propitious reproductive condition for the study species

Evolução diagenética e caracterização dos reservatórios da seção devoniana na Bacia do Rio do Peixe-Nordeste do Brasil

The Rio do Peixe Basin represents a main basin of northeastern Brazil and pioneering work positioned the rocks of this basin in the Early Cretaceous. However, a recent study, based on integrated pollen analysis from three wells, found an unprecedented siliciclastic sedimentary section, in the region, of early Devonian age. Therefore, the present study aims a detailed petrographic and petrological analysis of this devonian section, in the Rio do Peixe Basin and proposes a diagenetic evolution, to understand the characteristics of the porous system, identify the main reservoir petrofacies with the main factors impacting on the quality of these rocks as reservoirs and a quick study on the provenance of this section. The petrographic study was based on samples obtained from subsurface and surface. The diagenetic evolution of petrofacies and its identification were based only on subsurface samples and the study of provenance was based on surface samples. The thin sections were prepared from sandstones, pelites and sandstones intercalated with pelites. The original detrital composition for this section is arcosean and the main diagenetic processes that affected these rocks occur in various depths and different conditions, which resulted in extensive diagenetic variety. The following processes were identified: early fracture and healing of grains; albitization of K-feldspar and plagioclase; siderite; precipitation of silica and feldspar; mechanical infiltration of clay and its transformation to illite/esmectite and illite; autigenesis of analcime; dissolution; autigenesis of chlorite; dolomite/ferrous dolomite/anquerite; apatite; calcite; pyrite; titanium minerals and iron oxide-hidroxide. The occurrence of a recently discovered volcanism, in the Rio do Peixe Basin, may have influenced the diagenetic evolution of this section. Three diagenetic stages affected the Devonian section: eo, meso and telodiagenesis. This section is compositionally quite feldspathic, indicating provenance from continental blocks, between transitional continental and uplift of the basement. From this study, we observed a wide heterogeneity in the role of the studied sandstones as reservoirs. Seven petrofacies were identified, taking into account the main diagenetic constituent responsible for the reduction of porosity. It is possible that the loss of original porosity was influenced by intense diagenesis in these rocks, where the main constituent for the loss of porosity are clays minerals, oxides and carbonate cement (calcite and dolomite)

Estratégia reprodutiva do peixe hermafrodita mussum, Synbranchus marmoratus Osteichthyes, Synbranchidae em um açude do Rio Grande do Norte, Brasil

Reproductive strategy of the hermaphrodite fish the marbled swamp eel, Synbranchus marmoratus (Bloch, 1795) (Osteichthyes: Synbranchidae) was investigated in the Marechal Dutra reservoir, Acari, Rio Grande do Norte, using fish samples captured monthly during the period of July 2010 to July 2011. The limnological parameters and rainfall were verified. The captured fish specimens were numbered, weighed, measured, dissected and their gonads and liver were removed, weighed and identified as to sex and developmental stages of gonads. The length-weight relationship was determined for grouped sex. The size of first gonadal maturation, gonadosomatic index (GSI), condition factor (K) and hepatosomatic index (HSI) were calculated. The development stages of the gonads were investigated using macroscopic and histological techniques, besides the fecundity and reproductive period. The macroscopic characteristics and the histological development of gonads confirmed the four different sexual types in the sampled population: primary males, females, intersex and secondary males. The secondary males were bigger and heavier than all the other types. This species showed a negative allometric growth with a higher increase in length than weight. The size at which 50% of the females began the process of gonadal maturation was 43.5 cm of total length, and for secondary males it was 58.5 cm. Condition factor showed two peaks in February and in April 2011. IGS indicated a reproductive period from July to September 2010 and was negatively correlated with the condition factor and rainfall. IGS showed a negative correlation when compared with the condition factor and the rainy season. HSI was highest in February ad lowest in December. The reproductive period of this species occurs between the end of the rainy season and the beginning of the dry season. S. marmoratus presents a seasonal reproductive strategy which optimizes its reproductive success under the semiarid climatic conditions

Efeitos de peixes zooplanctívoros e onívoros sobre a resposta de comunidades planctônicas à fertilização por nutrientes

The food chain theory predict that presence of omnivory prevent the trophic cascade and could be a strong stabilizing factor over resource and consumer community dynamics, and that the nutrient enrichment destabilize populations dynamics. Most of the freshwater tropical reservoirs are eutrophic, and strategies that seek improve the water quality through the control of phytoplankton biomass and nutrient input, become essential for the improvement and preservation of water quality. The aim of this study was test the zooplanktivory (when larvae) and omnivory (when young and adult) effects of Nile Tilapia over the structure and dynamics of plankton communities, in addition or absence of nutrients enrichment. For this, one field experiment was performed with a factorial design 2x3 resulting in six treatments: control, without fish and nutrient (C); with omnivorous fish (O); with zooplanktivorous fish (Z); without fish and with enrichment of nutrients (NP); with omnivorous fish and nutrients (ONP); and, with zooplanktivorous fish and nutrients (ZNP). The two planktivory types reduced the zooplankton biomass and increased the phytoplankton biomass, but the omnivory of filter-feeding fish attenuated the trophic cascade magnitude. The fertilization by nutrients increases the nutrient concentrations in water and the phytoplankton biomass, but the effect on zooplankton is dependent of the trophic structure. In a general way, the effects of the fish and nutrient addition were addictive, but significant interactions among those factors were observed in the answer of some zooplankton groups. The effects of omnivorous fish over the temporal variability of phytoplankton and zooplankton biomass were very variable, the increase or reduce in variability of the plankton depending of the level of nutrients and of the analyzed variable. With base in this study, we conclude that the planktivory type exercised by the fish and the concentrations of nutrients in the water affects the force of pelagic trophic cascades and probably the success of biomanipulation programs for the handling of water quality in lakes and tropical reservoirs

Efeitos da tilápia do Nilo, Oreochromis niloticus, sobre a biomassa planctônica e a transparência da água ao longo de um gradiente de enriquecimento por nutrientes

The omnivorous filter-feeding fish, Nile tilapia (Oreochromis niloticus), can have negative effects on water quality enhancing the eutrophication process. These effects depend on the nutrient enrichment level in the water. We carried out a mesocosm experiment for five weeks in a tropical man-made lake in Brazil to test ifthe effects of tilapias depend on of the level of nutrient enrichment. The experiment lasted for 5 weeks and a factorial 2x5 experimental design was used where the presence and absence of tilapias were manipulated in combination to 5 different levels of nutrient load in a total of 10 treatments. A two way repeated measure ANOVA was performed to evaluate the effects of time (t), tilapia (F), nutrients (NP) and the interactions among these factors on: chlorophyll a, water transparency, total phosphorous, total nitrogen, N:P ratio, zooplankton biomass and phytoplankton biovolume. The tilapia effect was evident, but nutrient enrichment didn t have any effect on the variables analyzed. Tilapia decreased the water transparency, total zooplankton biomass, calanoid copepod biomass, nauplii copepod biomass and cladocerans biomass. On the other hand, tilapia had no effect on phytoplankton biovolume. This lack of effect on phytoplankton is probably due to tilapia grazing that may counteract the positive effect of tilapia on phytoplankton via trophic cascades and nutrient recycling. Hence, a reduction in tilapia stock would not be an effective way to reduce phytoplankton biomass and improve water quality