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A nested ice flow model was developed for eastern Dronning Maud Land to assist with the dating and interpretation of the EDML deep ice core. The model consists of a high-resolution higher-order ice dynamic flow model that was nested into a comprehensive 3-D thermomechanical model of the whole Antarctic ice sheet. As the drill site is on a flank position the calculations specifically take into account the effects of horizontal advection as deeper ice in the core originated from higher inland. First the regional velocity field and ice sheet geometry is obtained from a forward experiment over the last 8 glacial cycles. The result is subsequently employed in a Lagrangian backtracing algorithm to provide particle paths back to their time and place of deposition. The procedure directly yields the depth-age distribution, surface conditions at particle origin, and a suite of relevant parameters such as initial annual layer thickness. This paper discusses the method and the main results of the experiment, including the ice core chronology, the non-climatic corrections needed to extract the climatic part of the signal, and the thinning function. The focus is on the upper 89% of the ice core (appr. 170 kyears) as the dating below that is increasingly less robust owing to the unknown value of the geothermal heat flux. It is found that the temperature biases resulting from variations of surface elevation are up to half of the magnitude of the climatic changes themselves.

Serpentinized spinel peridotites of the Newfoundland margin drilled during ODP Leg 210 at Site 1277 have preserved, relic mineral compositions similar to the most depleted abyssal peridotites worldwide and different from those of the conjugate Iberian margin. The samples are derived from mass flows containing clasts of peridotite and gabbro and from in-situ basement, and are mostly mylonitic cpx-poor spinel harzburgites with Cr-rich spinels (Cr#0.35-0.66). Melting of the Newfoundland mantle occurred in the spinel peridotite field and probably exceeded the cpx-out phase boundary for some samples. Using proposed spinel peridotite melting models and experimentally derived phase diagrams, the Newfoundland harzburgites can be modeled as a residue after extraction of 14 to 20-25% melting. Basalts that are interleaved with mass flow deposits on top of the peridotite basement resemble normal to transitional mid-ocean ridge basalt. This, together with the unusually high Cr# of some spinel harzburgites suggest that the formation of basalts and partial melting of the underlying peridotite are not cogenetic. Among mantle samples some of the Newfoundland harzburgites approach mineral compositions of the Bay of island ophiolite and ophiolites from Japan that represent peridotites formed in an arc-setting. Thus, the peridotites drilled at Site 1277 may represent inherited (Caledonian or older) subarc mantle that was exhumed close to the ocean floor during the rifting evolution of the Atlantic. Compared to the spinel harzburgites from Newfoundland, the peridotites from the conjugate Iberian margin are, on average, less depleted and provide evidence for local equilibration in the plagioclase stability field. This can either be explained by an inherited, primary, Ca-richer composition of the Iberia peridotite, or, alternatively, by local melt impregnation and stagnation during continental rifting, and thus refertilizing previously depleted (arc-related) peridotite.

A long-standing question in Paleogene climate concerns the frequency and mechanism of transient greenhouse gas-driven climate shifts (hyperthermals). The discovery of the greenhouse gas-driven Paleocene-Eocene Thermal Maximum (PETM; ~55 Ma) has spawned a search for analogous events in other parts of the Paleogene record. On the basis of high-resolution bulk sediment and foraminiferal stable isotope analyses performed on three lower Danian sections of the Atlantic Ocean, we report the discovery of a possible greenhouse gas-driven climatic event in the earliest Paleogene. This event - that we term the Dan-C2 event - is characterized by a conspicuous double negative excursion in delta13C and delta18O, associated with a double spike in increased clay content and decreased carbonate content. This suggests a double period of transient greenhouse gas-driven warming and dissolution of carbonates on the seafloor analogous to the PETMin the early Paleocene at ~65.2 Ma. However, the shape of the two negative carbon isotope excursions that make up the Dan-C2 event is different from the PETM carbon isotope profile. In the Dan-C2 event, these excursions are fairly symmetrical and each persisted for about ~40 ky and are separated by a short plateau that brings the combined duration to ~100 ky, suggesting a possible orbital control on the event. Because of the absence of a long recovery phase, we interpret the Dan-C2 event to have been associated with a redistribution of carbon that was already in the biosphere. The Dan-C2 event and other early Paleogene hyperthermals such as the short-lived early Eocene ELMO eventmay reflect amplification of a regular cycle in the size and productivity of the marine biosphere and the balance between burial of organic and carbonate carbon.

Aquaculture is one of the most prosperous economic sectors. Nevertheless, the natural outbreaks of several infectious diseases make the sector to deal with important economic losses. One of the most important pathogens in the Mediterranean Sea is nodavirus (NNV). NNV is the agent causing viral encephalopathy and retinopathy in more than 170 fish species including some of the most impact in Spanish hatcheries as European sea bass (Dicentrarchus labrax). Antimicrobial peptides (AMPs) are short aminoacidic sequences which constitute important mediators of the innate immune response in teleost fish. AMPs can kill directly a broad range of pathogens such as bacteria or viruses and modulate the host immune response leading to a more effective clearance of pathogens. These properties along with the world emergency in antimicrobial resistance (AMR) make AMPs good candidates to replace traditional antimicrobials. Therefore, we aimed to analyze the molecular regulation of European sea bass defensin beta genes upon NNV infection and after NNV vaccination. To achieve our objective, European sea bass were infected with NNV and samples of head-kidney (HK), brain and gonad were taken. In addition, gonadal cells from healthy males were in vitro stimulated with NNV. Then, ovary samples of control females or vaccinated against NNV (pBAD vaccine) were taken, as well as fertilized eggs and larvae from the same groups. To support our data, we also analyzed in silico the potential antiviral activity of the protein encoded by the studied genes. Our results show that defensin beta 1 gene is up-regulated upon in vivo NNV infection even if in the in silico study showed the lesser predicted activity. Interestingly, the in vitro NNV challenge resulted in no variation of the defensin beta 1 gene, while defensin beta 2.1 and 2.2 genes were blocked upon this stimulus. Strikingly, females vaccinated with pBAD greatly down-regulate defensin beta 2.2 expression. Moreover, larvae from vaccinated mother up-regulate all defensin beta genes. In conclusion, defensin beta 1 gene seems to be involved in the defense against viruses while defensin beta 2 genes appear to possess a more specific function in gonad.

ODP Site 1078 situated under the coast of Angola provides the first record of the vegetation history for Angola. The upper 11 m of the core covers the past 30 thousand years, which has been analysed palynologically in decadal to centennial resolution. Alkenone sea surface temperature estimates were analysed in centennial resolution. We studied sea surface temperatures and vegetation development during full glacial, deglacial, and interglacial conditions. During the glacial the vegetation in Angola was very open consisting of grass and heath lands, deserts and semi-deserts, which suggests a cool and dry climate. A change to warmer and more humid conditions is indicated by forest expansion starting in step with the earliest temperature rise in Antarctica, 22 thousand years ago. We infer that around the period of Heinrich Event 1, a northward excursion of the Angola Benguela Front and the Congo Air Boundary resulted in cool sea surface temperatures but rain forest remained present in the northern lowlands of Angola. Rain forest and dry forest area increase 15 thousand years ago. During the Holocene, dry forests and Miombo woodlands expanded. Also in Angola globally recognised climate changes at 8 thousand and 4 thousand years ago had an impact on the vegetation. During the past 2 thousand years, savannah vegetation became dominant.

Coastal upwelling regions have been identified as sites of enhanced CH4 emissions to the atmosphere. The coastal upwelling area off Mauritania (NW Africa) is one of the most biologically productive regions of the world's ocean but its CH4 emissions have not been quantified so far. More than 1000 measurements of atmospheric and dissolved CH4 in the surface layer in the upwelling area off Mauritania were performed as part of the German SOPRAN (Surface Ocean Processes in the Anthropocene) study during two cruises in March/April 2005 (P320/1) and February 2007 (P348). During P348 enhanced CH4 saturations of up to 200% were found close to the coast and were associated with upwelling of South Atlantic Central Water. An area-weighted, seasonally adjusted estimate yielded overall annual CH4 emissions in the range from 1.6 to 2.9 Gg CH4. Thus the upwelling area off Mauritania represents a regional hot spot of CH4 emissions but seems to be of minor importance for the global oceanic CH4 emissions.

A chronology called EDML1 has been developed for the EPICA ice core from Dronning Maud Land (EDML). EDML1 is closely interlinked with EDC3, the new chronology for the EPICA ice core from Dome-C (EDC) through a stratigraphic match between EDML and EDC that consists of 322 volcanic match points over the last 128 ka. The EDC3 chronology comprises a glaciological model at EDC, which is constrained and later selectively tuned using primary dating information from EDC as well as from EDML, the latter being transferred using the tight stratigraphic link between the two cores. Finally, EDML1 was built by exporting EDC3 to EDML. For ages younger than 41 ka BP the new synchronized time scale EDML1/EDC3 is based on dated volcanic events and on a match to the Greenlandic ice core chronology GICC05 via 10Be and methane. The internal consistency between EDML1 and EDC3 is estimated to be typically ~6 years and always less than 450 years over the last 128 ka (always less than 130 years over the last 60 ka), which reflects an unprecedented synchrony of time scales. EDML1 ends at 150 ka BP (2417 m depth) because the match between EDML and EDC becomes ambiguous further down. This hints at a complex ice flow history for the deepest 350 m of the EDML ice core.

A combination of changes in the species composition of the radiolarian populations, and in the sediment chemical composition (content and mass accumulation rates of carbonate, organic carbon, and selected major and trace elements, with special attention paid to Ba) is used to reconstruct the variations in upwelling activity over the last 250 kyr in the Socotra gyre area (Somali-Socotra upwelling system, NW Indian Ocean). In the Socotra gyre (Core MD 962073 at 10°N), the variations in upwelling intensity are reconstructed by the upwelling radiolarian index (URI) while the thermocline/surface radiolarian index (TSRI) testifies to productivity variations during non-upwelling intervals. Despite an origin related both to marine and terrigenous inputs, the geochemical records of organic carbon, silica, and trace elements (Ba, P, Cu, and Zn) normalized to Al are controlled by the variations in surface paleoproductivity. The data indicate a continuous increase in upwelling intensity during the last 250 kyr with a maximum activity within the MIS 3, while high productivity periods in between the upwelling seasons occurred both during glacial and interglacial intervals. A comparison of our data with published observations from another gyre of the Somalian upwelling area located at 5°N in the Somali gyre area shows differences regarding periods of upwelling activity and their geochemical imprint. Three hypotheses are proposed to explain these differences: (1) changes in the planktonic community, resulting in more silica-rich deposits in the Socotra gyre, and more carbonate-rich deposits in the Somali gyre, that are controlled by differences in the source water of the upwelling; (2) a more important terrigenous input in the southern gyre; and (3) a different location of the sites relative to the geographic distribution of the upwelling gyres and hydrologic fronts.

Interstitial water samples from Leg 129, Sites 800, 801, and 802 in the Pigafetta and Mariana basins (central western Pacific), have been analyzed for major elements, B, Li, Mn, Sr, and 87Sr/86Sr. At all sites waters show enrichment in Ca and Sr and are depleted in Mg, K, Na, SO4, B, alkalinity, and 87Sr compared to seawater. These changes are related to alteration of basaltic material into secondary smectite and zeolite and recrystallization of biogenic carbonate. Water concentration depth profiles are characterized by breaks due to the presence of barriers to diffusion such as chert layers at Sites 800 and 801 and highly cemented volcanic ash at Site 802. In Site 800, below a chert layer, concentration depth profiles are vertical and reflect slight alteration of volcanic matter, either in situ or in the upper basaltic crust. Release of interlayer water from clay minerals is likely to induce observed Cl depletions. At Site 801, two units act as diffusion barrier and isolate the volcaniclastic sediments from ocean and basement. Diagenetic alteration of volcanic matter generates a chemical signature similar to that at Site 800. Just above the basaltic crust, interstitial waters are less evolved and reflect low alteration of the crust, probably because of the presence in the sediments of layers with low diffusivities. At Site 802, in Miocene tuffs, the chemical evolution generated by diagenetic alteration is extreme (Ca = 130 mmol, 87Sr/86Sr = 0.7042 at 83 meters below seafloor) and is accompanied by an increase of the Cl content (630 mmol) due to water uptake in secondary hydrous phases. Factors that enhance this evolution are a high sediment accumulation rate, high cementation preventing diffusive exchange and the reactive composition of the sediment (basaltic glass). The chemical variation is estimated to result in the alteration of more than 20% of the volcanic matter in a nearly closed system.