Histoire naturelle des poissons, ou, Ichthyologie générale / par Aug. Duméril ; ouvrage accompagné de planches.

2

Zoology of New York; or, The New York Fauna; comprising detailed descriptions of all the animals hitherto observed within the state of New York, with brief notices of those occasionally found near its borders, and accompanied by appropriate illustrations /

Part 5, Mollusca

Verhandelingen uitgegeven door het Zeeuwsch Genootschap der Wetenschappen te Vlissingen.

Vol 15 - Vol 15

Flutuação populacional circanual de coleópteros em granja avícola, em Pelotas, RS, Brasil

Com o objetivo de conhecer a flutuação populacional de coleópteros na granja de aves do Conjunto Agrotécnico Visconde da Graça, em Pelotas, RS, foram utilizados seis métodos de coleta: 1 (fezes de galinhas com 0 a 7 dias); 2 (7 a 14 dias); 3 (14 a 21 dias); 4 (0 a 21 dias); 5 (fezes acumuladas) e 6 (armadilhas de tubo). Análises de regressão polinomial foram realizadas independentemente dos métodos de coleta. O estudo foi realizado de agosto de 1998 a julho de 1999. Foram capturados 12.449 coleópteros representados pelas seguintes espécies Carcinops troglodytes (Paykull, 1811) (Histeridae) (6.444); Alphitobius diaperinus (Panzer, 1797) (Tenebrionidae) (2.896); Somotrichus unifasciatus (Dejean, 1792) (Carabidae) (1.190); Gnathocerus cornutus (Fabricius, 1798) (Tenebrionidae) (947); Euxestus sp. (Cerylonidae) (394); Euspilotus rubriculus (Marseul, 1855) (Histeridae) (213); Ontholestes sp. (Staphylinidae) (190); Dactylosternum sp. (Hydrophilidae) (93); Mezium americanum (Laporte, 1840) (Ptinidae) (43); Palorus subdepressus (Wollaston, 1864) (Tenebrionidae) (27); Tenebroides mauritanicus (L., 1758) (Trogossitidae) (8); Xyleborus ferrugineus (Fabricius, 1801) (Scolytidae) (1); e espécimens não identificados de Dermestidae (3). O maior número de espécies ocorreu nos meses de março e julho e o menor, no mês de setembro. Em março foi registrada a maior abundância de coleópteros (2.159), enquanto que o menor índice de captura foi assinalado em outubro (633). A flutuação populacional foi estimada para C. troglodytes, A. diaperinus, S. unifasciatus, G. cornutus, Euxestus sp., E. rubriculus, Ontholestes sp. e Dactylosternum sp.

Buccal apparatus and gastrointestinal tract dimensions associated to the diet of early life stages of Centropomus undecimalis (Centropomidae, Actinopterygii)

The present study aims to compare the buccal apparatus and gastrointestinal tract of early life stages of Centropomus undecimalis (Bloch, 1792), and relate them to its diet. A total of 190 individuals collected with a channel net in the Catuama estuary (07º40'9.9''S, 34º50'36.7''W), northern coast of the state of Pernambuco, were examined. Morphometrical and meristic data were analyzed for the two initial developmental periods (larval and juvenile). Their digestive tube was morphologically characterized and its content identified. The longest transverse axis of food items was measured, and compared to the standard length (SL) and mouth gape size (D) of the individuals. Body measurement regressions differed significantly (p<0.001) between larvae and juveniles. The stomachs with food content (n=118 individuals) presented a proportion of 62% full and 30% empty (being 8% damaged). They differed in relation to the fullness level and presented a coiled shape when empty. The number of food items in relation to SL and D did not present an evident correlation. Larvae (SL<10 mm) feed on small copepods, while juveniles (SL=11.1 to 64.7 mm) ingest larvae of various decapod species, showing a distinct diet between these initial developmental stages.

Botanisches Taschenbuch für die Anfänger dieser Wissenschaft und der Apothekerkunst.

1792

Histoire naturelle des reptiles, avec figures dessinées d'après nature / par C. S. Sonnini et par P. A. Latreille.

2

Creating and using a non-dedicated HPC cluster with ParallelKnoppix

This note describes ParallelKnoppix, a bootable CD that allows econometricians with average knowledge of computers to create and begin using a high performance computing cluster for parallel computing in very little time. The computers used may be heterogeneous machines, and clusters of up to 200 nodes are supported. When the cluster is shut down, all machines are in their original state, so their temporary use in the cluster does not interfere with their normal uses. An example shows how a Monte Carlo study of a bootstrap test procedure may be done in parallel. Using a cluster of 20 nodes, the example runs approximately 20 times faster than it does on a single computer.

Catabolite repression in Pseudomonas aeruginosa PAO1 regulates the uptake of C4 -dicarboxylates depending on succinate concentration.

In Pseudomonas aeruginosa carbon catabolite repression (CCR) is exerted by the CbrA/B-CrcZ-Crc global regulatory system. Crc is a translational repressor that, in the presence of preferred carbon sources, such as C4 -dicarboxylates, impairs the utilization of less preferred substrates. When non-preferred substrates are present, the CrcZ sRNA levels increase leading to Crc capture, thereby allowing growth of the bacterium at the expense of the non-preferred substrates. The C4 -dicarboxylate transport (Dct) system in P. aeruginosa is composed of two main transporters: DctA, more efficient at mM succinate concentrations, and DctPQM, more important at μM. In this study, we demonstrate that the Dct transporters are differentially regulated by Crc, depending on the concentration of succinate. At high concentrations, Crc positively regulates the expression of the dctA transporter gene and negatively regulates dctPQM post-transcriptionally. The activation of dctA is explained by a Crc-mediated repression of dctR, encoding a transcriptional repressor of dctA. At low succinate concentrations, Crc regulation is impaired. In this condition, CrcZ levels are higher and therefore more Crc proteins are sequestered, decreasing the amount of Crc available to perform CCR on dctR and dctPQM. As a result, expression of dctA is reduced and that of dctPQM is increased.