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Through the processes of the biological pump, carbon is exported to the deep ocean in the form of dissolved and particulate organic matter. There are several ways by which downward export fluxes can be estimated. The great attraction of the 234Th technique is that its fundamental operation allows a downward flux rate to be determined from a single water column profile of thorium coupled to an estimate of POC/234Th ratio in sinking matter. We present a database of 723 estimates of organic carbon export from the surface ocean derived from the 234Th technique. Data were collected from tables in papers published between 1985 and 2013 only. We also present sampling dates, publication dates and sampling areas. Most of the open ocean Longhurst provinces are represented by several measurements. However, the Western Pacific, the Atlantic Arctic, South Pacific and the South Indian Ocean are not well represented. There is a variety of integration depths ranging from surface to 220m. Globally the fluxes ranged from -22 to 125 mmol of C/m**2/d. We believe that this database is important for providing new global estimate of the magnitude of the biological carbon pump.

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The strength and geometry of the Atlantic meridional overturning circulation is tightly coupled to climate on glacial-interglacial and millennial timescales, but has proved difficult to reconstruct, particularly for the Last Glacial Maximum. Today, the return flow from the northern North Atlantic to lower latitudes associated with the Atlantic meridional overturning circulation reaches down to approximately 4,000 m. In contrast, during the Last Glacial Maximum this return flow is thought to have occurred primarily at shallower depths. Measurements of sedimentary 231Pa/230Th have been used to reconstruct the strength of circulation in the North Atlantic Ocean, but the effects of biogenic silica on 231Pa/230Th-based estimates remain controversial. Here we use measurements of 231Pa/230Th ratios and biogenic silica in Holocene-aged Atlantic sediments and simulations with a two-dimensional scavenging model to demonstrate that the geometry and strength of the Atlantic meridional overturning circulation are the primary controls of 231Pa/230Th ratios in modern Atlantic sediments. For the glacial maximum, a simulation of Atlantic overturning with a shallow, but vigorous circulation and bulk water transport at around 2,000 m depth best matched observed glacial Atlantic 231Pa/230Th values. We estimate that the transport of intermediate water during the Last Glacial Maximum was at least as strong as deep water transport today.

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Title page and initials designed by Samuel Warner.

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This volume has been designated "sixième volume" in the Catalogue, for a collection known under the title of the repository, Cabinet du roi. The engravings were prepared between 1672 and 1689 by various engravers: Le Pautre, Le Clerc, Chauveau, Edelinck, Picart, Baudet, Silvestre, Simonneau and Chatillon. They were issued individually at the outset, collected, and in this instance issued in uniform format. The plates of the Labyrinthe, 15 x 8.5 cm., have been printed on 4 leaves of 9 and 1 leaf of 5.

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Sassetta (Stefano di Giovanni); 1 ft. 2 3/4 in. x 1 ft. 11 1/4 in.; tempera on poplar

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Series title also at head of t.-p.

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Mode of access: Internet.

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Mode of access: Internet.

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Contiene: Aelii Antonii Nebrissens¯. De litteris hebraicis cum quibusda[m] annotationibus in scripturam sacra[m]¯

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Incluye: Vita Henrici quarti Caesaris Augusti ... ; Oratio excusatoria ... regi Vladislao ad Ungariam missa ; Articuli Johannis Wiclephi Angli, impugnati a Wilhelmus Widefordus ; Articuli Johannis Wiclephi Angli, damnati per Concilium Constantiense ; Rationes et motiva, ac reprobationes articulorum Wiclephi, et sequacis sui Ioannis Huss, in Concilio Constantiensi damnatorum ; Quonam pacto doctrina Johannis Wiclephi in Bohemiam venerit ... ex historia Bohemorum, cuius author fuit Aeneas Sylvius ; Leonardo Areteni ... adversum hypocritas libellus ; Synodus Aribonis Archiepiscopi Moguntini, cum Coepiscopis ac Abbatibus suis, anno Domini MXXIII apud Saligunstat celebrata ; Quomodo Bohemi vocati, productique sint ad Basiliensem synodum oecumenicam ... commentariis compendio relatum ; Examen magistrale ac theologicale doctoris Ioannis de VVesalia ... ; Sententia damnationis doctrinae Johannis Wiclephi ...

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Mode of access: Internet.