Quaternary development of resilient reefs on the subsiding kimberley continental margin, Northwest Australia

The Kimberley region in remote northwest Australia has poorly known reef systems of two types; coastal fringing reefs and atoll-like shelf-edge reefs. As a major geomorphic feature (from 12ºS to 18ºS) situated along a subsiding continental margin, the shelf edge reefs are in a tropical realm with warm temperatures, relatively low salinity, clear low nutrient waters lacking sediment input, and Indo-West Pacific corals of moderate diversity. Seismic architecture of the Rowley Shoals reveals that differential pre-Holocene subsidence and relative elevation of the pre-Holocene substrate have controlled lagoon sediment infill and reef morphology, forming an evolutionary series reflecting differential accommodation in three otherwise similar reef systems.The Holocene core described for North Scott Reef confirms previous seismic interpretations, and provides a rare ocean-facing reef record. It demonstrates that the Indo-Pacific reef growth phase (RG111) developed during moderate rates of sea level rise of 10 mm/year from 11 to about 7-6.5 ka BP until sea level stabilization, filling the available 27 m of pre-Holocene accommodation. Despite the medium to high hydrodynamic energy imposed by the 4m tides, swell waves and cyclones the reef-building communities represent relatively low-wave energy settings due to their southeast facing and protection afforded by the proximity of the South Reef platform. This study demonstrates the resilience of reefs on the subsiding margin whilst linking Holocene reef morphology to the relative amount of pre-Holocene subsidence

The Geological Society

p. 55-71The inner portion of the continental shelf of Rio Grande do Norte State, Brazil has been investigated by Landsat-TM imagery and by scuba diving. The area experiences high-energy, shoreline and shelf-margin parallel currents driven by a combination of oceanic, tidal and wave processes. The high meso-tidal range (<4 m) further distributes the high-energy waters over the entire inner shelf region (0-25 m). This shelf is a high-energy, distally steepened ramp in which the distribution of carbonate and siliciclastic facies belts is controlled by the energy of the environment, the sources of siliciclastic sediment and the Quaternary history of the area. Carbonate sediments are generated throughout the sublittoral zone and are dominated by calcareous red and green algae. SmalL, low-diversity coral patch reefs occur in shallow areas. Quartz-rich sands form beaches and subaerial longitudinal dunes, and an offshore, submarine, sandstone outcrop interpreted as a former Quaternary shoreline. This sandstone has been eroded during the Holocene transgression to generate quartz sands deposited in a train of transverse dunes migrating parallel to the coast. Longitudinal sand ribbons comprising bioclastic gravelly sands attest to high-energy, shore-parallel currents in the inner shelf. Branching coralline algae (maErl) form stabilized sea-floor areas. Preliminary 14C dating indicates a Pleistocene highstand period when coarse algal sands accumulated. Holocene lowstand conditions spread quartz-rich sands over the inner ramp area, which were reworked during the Holocene transgression. Present-day erosion, transport and in situ carbonate production results in mixing of these earlier carbonate and siliciclastic units. The Brazilian ramp has similar, but narrower morphology, when compared with the distally steepened ramps of the Yucatan and west Florida. All three ramps are swept by coastline-parallel currents. In Brazil, the higherenergy, windward-facing, inner ramp has calcareous algal sands and patch reefs compared with the inner ramps of the leeward-facing Gulf of Mexico examples that accumulate molluscan sands. Outer ramp facies in each example are planktonic foraminiferal oozes

Estrutura e dinâmica de comunidades bentônicas dominadas por macrófitas na zona intramareal da Praia de Jacaraípe, Espírito Santo, Brasil

O recife parcialmente exposto da Praia de Jacaraípe é formado por algas calcárias vermelhas incrustantes com até 40 cm em espessura sobre uma comunidade recifal holocênica. Este trabalho visa descrever a composição da flora atual e estrutura do fitobentos desta comunidade, todavia não estudada. O levantamento ocorreu no verão e inverno, no platô e borda recifal. Foram amostrados 10 quadrados aleatórios ao longo de transectos de 20 m em cada habitat. Os resultados apontam para a presença de doze clorofíceas, quatro feofíceas, 34 rodofíceas e uma fanerógama marinha, totalizando 35 gêneros e 51 táxons. Foi identificada uma variação sazonal na riqueza específica somente na borda recifal, a qual apresentou uma flora menos rica no inverno. As algas calcárias articuladas tiveram maior biomassa e cobertura nas duas épocas estudadas. A distribuição espacial e temporal da flora está em acordo com padrões de tipo de substrato, hidrodinâmica e turbidez da água do mar encontrados em áreas recifais de todo o Brasil

Ginkgo biloba extract (GbE) attenuates obesity and anxious/depressive-like behaviours induced by ovariectomy

Abstract While several pieces of evidence link obesity and mood disorders in menopause, the mechanisms involved are not yet fully understood. We have previously demonstrated that Ginkgo biloba extract (GbE) both attenuated diet-induced obesity of male rats and restored serotonin-induced hypophagia in ovariectomized female rats. The present study aimed at exploring whether GbE treatment ameliorates ovariectomy-related obesity and anxious/depressive-like behaviours. Wistar female rats were either ovariectomized (OVX) or sham-operated (Sham). After 2 months, either 500 mg/kg of GbE or vehicle were administered daily by gavage for 14 days. Anxious/depressive-like behaviours were assessed by the Elevated Plus Maze and the Forced Swim Tests, respectively. Ovariectomy caused high visceral adiposity, hyperleptinemia, and hypercholesterolemia, and increased the anxiety index (p = 0.048 vs. Sham + GbE) while it decreased the latency to immobility (p = 0.004 vs. Sham). GbE treatment in OVX rats improved body composition, adiponectin levels and blood lipid profile. It also reduced the anxiety index (p = 0.004) and increased the latency to immobility (p = 0.003) of OVX rats. Linear regression analysis demonstrated that leptin (p = 0.047) and total cholesterol levels (p = 0.022) were associated with anxious-like behaviours while body adiposity (p = 0.00005) was strongly associated with depressive-like behaviours. The results showed that GbE therapy was effective in attenuating the deleterious effects of ovariectomy on body composition, lipid profile, and anxious/depressive-like behaviours. Further studies are warranted to better understand the therapeutic potential of GbE in menopause

Projeto-piloto do Primeiro Inquérito Nacional de Populações Expostas a Substâncias Químicas, 2008-2009

Para viabilizar a futura realização de um Inquérito Nacional de Populações Expostas a Substâncias Químicas, executou-se um projeto-piloto para examinar a exequibilidade, testar e adequar metodologias e estabelecer parcerias. Foram realizados três estudos de corte transversal, respectivamente, com doadores de sangue residentes na Região Metropolitana de São Paulo-SP, conscritos do Exército Brasileiro e crianças escolares residentes no município do Rio de Janeiro-RJ, mediante aplicação de questionários e coleta de material biológico (sangue venoso e capilar, unha e cabelo) para análise de metais e compostos organoclorados persistentes. Concluiu-se que é viável a realização de um Inquérito Nacional, embora a estratégia de obtenção das amostras biológicas deva ser definida para cada subgrupo da população. Recomenda-se aproveitar as estruturas de serviços existentes para obtenção de amostras, utilizar matrizes tradicionais para maior comparabilidade e garantir sua realização periódica