Biogenic and terrigeneous components in ODP Leg 108 holes

Five Ocean Drilling Program sites (657-661), which form a north-south transect off the western periphery of the Sahara, were selected to measure the long-term history of Saharan/Sahelian dust flux and fluvial sediment discharge and the fluxes of marine CaCO3 and opal over the last 8 m.y. Sites 658 and 659 served for high-resolution studies, and Sites 657, 660, and 661 for insights into the spatial patterns of dust flux. The nearshore mean flux of opal off Cap Blanc (21 °N) showed an abrupt increase about 3 Ma that appears to reflect the main onset of coastal upwelling fertility and enhanced trade winds. At the same time, the input of river-borne clay strongly decreased, suggesting a dry up of the central Saharan rivers. Later, marked short-lived spikes of clay and opal may indicate ongoing ephemeral pulses of fluvial runoff linked to peak interglacial stages. Given the zonal dust discharge centered near 18 °N at Site 659, the aridification of the south Sahara and Sahel increased in several steps: at 4.6, 4.3, and especially at 4.0, 3.6, and 2.1 Ma, and again, at 0.8 Ma. The late Miocene and earliest Pliocene were humid. Although the central and north Saharan climate appears to be linked to the glaciation history of the Northern Hemisphere, the long-term aridification further south followed a different schedule. The spatial distribution of quartz accumulation suggests that the dust outbreaks linked to the Intertropical Convergence Zone during summer did not shift in latitude back to 4.0 Ma, at least. The short-term variations of dust output over the last 0.5 m.y. followed orbital scale pulses with a strong precessional signal, showing a link of Sahelian humidity changes to the variation of sea-surface temperature and evaporation in the tropical Atlantic.

Median grain size and distribution of sand in ODP Hole 108-660A (Fig. 5)

50 m of Middle Eocene pure radiolarian ooze were drilled at ODP Site 660 in the equatorial East Atlantic, 80 km northeast of the Kane Gap. The oozes comprise a 10 m high and 2 km broad mound of seismic reverberations, covered by manganese-rich sediment, and contain trace amounts of sponge spicules and diatoms, negligible organic carbon (0.15%), clay, and variable amounts of pyrite. The yellow to pale brown silty sediments are relatively coarse-grained (30-45% coarser than 6 µm), little bioturbated, and commonly massive or laminated on a cm-scale. The unlithified radiolarian ooze may indicate an interval of high oceanic productivity, probably linked to a palaeoposition of Site 660 close to the equatorial upwelling belt during Middle Eocene time. The absence of organic matter, however, and both the laminated bedding and the mound-like structure of the deposit on the lower slope of a continental rise indicate deposition by relatively intense contour currents of oxygen-rich deep water, which passed through the Kane Gap, winnowed the fine clay fraction, and prevented the preservation of organic carbon. The ooze may be either a contourite-lag deposit, or a contourite accumulation of displaced radiolarians, originating south of the Kane Gap and being deposited in its northern lee, thus documenting the passage of a strong cross-equatorial bottom-water current formed near Antarctica. These Eocene contourites may be an analogue for ancient radiolarites in the Tethyan Ocean.

Friedrich Bergammer (Fritz Glueckselig) standing in the doorway of the gallery store M. Glueckselig & Son; 108 East 57th Street, New York Portraits Men

Digital Image

Sapientia, 1973, Vol. XXVIII, nº 108 (número completo)

Contenido: Un hombre y un mundo sin sentido / Ocostavio N. Derisi – Existencia y cultura / Alberto Caturelli – La cuestión “De aeternitate mundi” : posiciones doctrinales / Omar Argerami – Educación y trascendencia / J. E. Bolzán – Notas y comentarios -- Bibliografía

Diário da Constituinte [gravação de vídeo] : [programa n. 108]

Os Constituintes consideram que é dever do Estado proteger as crianças. João de Deus Antunes (PDT-RS) diz que o menor vai ser um dos mais privilegiados na nova carta constitucional. Pontos fundamentais dos direitos da criança: direito à vida, à saúde, à alimentação e à educação; diireito à assistência social, mesmo que os pais não contribuam para a previdência; proteção aos menores carentes e infratores; legislação especial sobre o trabalho do menor. Wilma Maia (PDS-RN) afirma que a nova Constituição tem de fazer cumprir os princípios de proteção dos menores, a começar pela educação, baseada um uma nova concepção, que ensine as crianças seus direitos e seus deveres. Robson Marinho (PMDB-SP) considera que no texto da nova Constituição estão assegurados os direitos básicos da criança. Mário Covas (PMDB-SP) acompanha as reuniões da Comissão de Sistematização e acredita na compatibilização dos diferentes textos feitos pelas distintas correntes políticas na Assembleia Nacional Constituinte (ANC). Artur da Távola (PMDB-RJ) aprova a permanência dos pontos mantidos no substitutivo da Comissão de Comunicação, especialmente as quatro finalidades da comunicação: cultural, educativa, regionalização da produção cultural e divulgação da cultura nacional. Bernardo Cabral (PMDB-AM), Relator da Comissão de Sistematização, faz balanço dos trabalhos e dos prazos. Na sessão O Povo Pergunta, cidadão quer saber o que está sendo decidido quanto a doação de órgãos. Uldurico Pinto (PMDB-BA) responde que todo cidadão é um doador em potencial, salvo aqueles que a família não permitir. Bernardo Cabral; João de Deus Antunes; Wilma Maia; Robson Marinho; Mário Covas; Fernando Henrique Cardoso; Arthur da Távola; Ulsorico Pinto;

Benthic habitat mapping in the Olympic Coast National Marine Sanctuary: Classification of side scan sonar data from survey HMPR-108-2002-01: Version I

In September 2002, side scan sonar was used to image a portion of the sea floor in the northern OCNMS and was mosaiced at 1-meter pixel resolution using 100 kHz data collected at 300-meter range scale. Video from a remotely-operated vehicle (ROV), bathymetry data, sedimentary samples, and sonar mapping have been integrated to describe geological and biological aspects of habitat and polygon features have been created and attributed with a hierarchical deep-water marine benthic classification scheme (Greene et al. 1999). The data can be used with geographic information system (GIS) software for display, query, and analysis. Textural analysis of the sonar images provided a relatively automated method for delineating substrate into three broad classes representing soft, mixed sediment, and hard bottom. Microhabitat and presence of certain biologic attributes were also populated into the polygon features, but strictly limited to areas where video groundtruthing occurred. Further groundtruthing work in specific areas would improve confidence in the classified habitat map. (PDF contains 22 pages.)

A fully integrated 660 MHz low-swing energy-recycling DC-DC converter

A fully integrated 0.18 μm DC-DC buck converter using a low-swing "stacked driver" configuration is reported in this paper. A high switching frequency of 660 MHz reduces filter components to fit on chip, but this suffers from high switching losses. These losses are reduced using: 1) low-swing drivers; 2) supply stacking; and 3) introducing a charge transfer path to deliver excess charge from the positive metal-oxide semiconductor drive chain to the load, thereby recycling the charge. The working prototype circuit converts 2.2 to 0.75-1.0 V at 40-55 mA. Design and simulation of an improved circuit is also included that further improves the efficiency by enhancing the charge recycling path, providing automated zero voltage switching (ZVS) operation, and synchronizing the half-swing gating signals. © 2009 IEEE.

Low-threshold-current and high-out-power 660 nm laser diodes with a p-GaAs current blocking layer for DVD-RAM/R

We investigate a new structure of high-power 660-nm AlGaInP laser diodes. In the structure, a p-GaAs layer is grown on the ridge waveguide serving as the current-blocking layer, and nonabsorbing windows are only fabricated near the cavity facets to increase the catastrophic-optical-damage level. Stable fundamental mode operation was achieved at up to 80 mW without kinks, and the maximum output power was 184 mW at 22 degrees C. The threshold current was 40 mA.