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  • 1
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    Nature Publishing Group
    In:  Nature Geoscience, 1 (3). pp. 169-172.
    Publikationsdatum: 2017-03-13
    Beschreibung: Although rising global sea levels will affect the shape of coastlines over the coming decades1, 2, the most severe and catastrophic shoreline changes occur as a consequence of local and regional-scale processes. Changes in sediment supply3 and deltaic subsidence4, 5, both natural or anthropogenic, and the occurrences of tropical cyclones4, 5 and tsunamis6 have been shown to be the leading controls on coastal erosion. Here, we use satellite images of South American mangrove-colonized mud banks collected over the past twenty years to reconstruct changes in the extent of the shoreline between the Amazon and Orinoco rivers. The observed timing of the redistribution of sediment and migration of the mud banks along the 1,500 km muddy coast suggests the dominant control of ocean forcing by the 18.6 year nodal tidal cycle7. Other factors affecting sea level such as global warming or El Niño and La Niña events show only secondary influences on the recorded changes. In the coming decade, the 18.6 year cycle will result in an increase of mean high water levels of 6 cm along the coast of French Guiana, which will lead to a 90 m shoreline retreat.
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  • 2
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    Nature Publishing Group
    In:  Nature Geoscience, 2 (12). pp. 886-890.
    Publikationsdatum: 2018-01-04
    Beschreibung: Zircon is a common mineral in continental crustal rocks. As it is not easily altered in processes such as erosion or transport, this mineral is often used in the reconstruction of geological processes such as the formation and evolution of the continents. Zircon can also survive under conditions of the Earth’s mantle, and rare cases of zircons crystallizing in the mantle significantly before their entrainment into magma and eruption to the surface have been reported1,2,3. Here we analyse the isotopic and trace element compositions of large zircons of gem quality from the Eger rift, Bohemian massif, and find that they are derived from the mantle. (U–Th)/He analyses suggest that the zircons as well as their host basalts erupted between 29 and 24 million years ago, but fragments from the same xenocrysts reveal U–Pb ages between 51 and 83 million years. We note a lack of older volcanism and of fragments from the lower crust, which suggests that crustal residence time before eruption is negligible and that most rock fragments found in similar basalts from adjacent volcanic fields equilibrated under mantle conditions. We conclude that a specific chemical environment in this part of the Earth’s upper mantle allowed the zircons to remain intact for about 20–60 million years.
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  • 3
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    Nature Publishing Group
    In:  Nature, 435 (7044). p. 901.
    Publikationsdatum: 2019-11-11
    Beschreibung: Scattered groups of these ancient fish may all stem from a single remote population. Coelacanths were discovered in the Comoros archipelago to the northwest of Madagascar in 1952. Since then, these rare, ancient fish have been found to the south off Mozambique, Madagascar and South Africa, and to the north off Kenya and Tanzania — but it was unclear whether these are separate populations or even subspecies. Here we show that the genetic variation between individuals from these different locations is unexpectedly low. Combined with earlier results from submersible and oceanographic observations1, 2, our findings indicate that a separate African metapopulation is unlikely to have existed and that locations distant from the Comoros were probably inhabited relatively recently by either dead-end drifters or founders that originated in the Comoros.
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  • 4
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    Nature Publishing Group
    In:  Nature, 447 . p. 383.
    Publikationsdatum: 2019-09-23
    Beschreibung: As the complex interplay of forces in the ocean responds to climate change, the dynamics of global ocean circulation are shifting.
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  • 5
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    Nature Publishing Group
    In:  Nature, 232 (28). pp. 37-38.
    Publikationsdatum: 2016-04-11
    Beschreibung: Marine Upper Jurassic sediments have recently been reported from South Africa (Knysna Outlier, Cape Province) for the first time1. They occur as shallow water, sandy clays (Brenton Beds) in association with terrestrial/fluviatile conglomerates and sandstones, which were deposited in an approximately east-west elongate intermontane basin between the Cape Fold mountains (formed of Lower Palaeozoic sediments). Post-Cretaceous erosion has reduced the original deposits to a series of small, isolated outliers, only two of which have been reported to contain marine sediments (Knysna, lower Upper Jurassic; Algoa, Valanginian2) (Fig. 1). Extensive Neocomian-Maas-trichtian outcrops are known from the continental shelf off to the south of South Africa3, and a complete mid-Jurassic to Upper Cretaceous marine succession is suspected on the Agulhas Bank infilling and overlying east-west striking, fault bounded folds of Lower Palaeozoic Cape Supergroup rocks as shown in Fig. 1 (R. V. D., in preparation and refs. 1 and 4).
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  • 6
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    Nature Publishing Group
    In:  Nature, 289 (5794). pp. 164-167.
    Publikationsdatum: 2016-04-11
    Beschreibung: There has been concern about recent temperature trends and the future effects of CO2 concentrations in the atmosphere1,2; but instrumental records only cover a few decades to a few centuries and it is essential that proxy data sources, such as pollen spectra from peats and lake sediments, be carefully interpreted as climate records. Several workers have shown statistically significant associations between the modern pollen rain and climatic parameters, an approach that by-passes the recognition of pollen/vegetation units. Statistically defined equations that associate abiotic and biotic elements are called transfer functions. We report here on the application of transfer function equations to nine middle and late Holocene peat and lake sediment sequences from northern Canada (Fig. 1).
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  • 7
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    Nature Publishing Group
    In:  Nature, 288 (5788). pp. 260-263.
    Publikationsdatum: 2016-03-01
    Beschreibung: Organic detritus passing from the sea surface through the water column to the sea floor controls nutrient regeneration, fuels benthic life and affects burial of organic carbon in the sediment record. Particle trap systems have enabled the first quantification of this important process. The results suggest that the dominant mechanism of vertical transport is by rapid settling of rare large particles, most likely of faecal pellets or marine snow of the order of 〉200 μm in diameter, whereas the more frequent small particles have an insignificant role in vertical mass flux4–6. The ultimate source of organic detritus is biological production in surface waters of the oceans. I determine here an empirical relationship that predicts organic carbon flux at any depth in the oceans below the base of the euphotic zone as a function of the mean net primary production rate at the surface and depth-dependent consumption. Such a relationship aids in estimating rates of decay of organic matter in the water column, benthic and water column respiration of oxygen in the deep sea and burial of organic carbon in the sediment record.
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  • 8
    Publikationsdatum: 2017-06-09
    Beschreibung: The new aromatic polyketides genoketide A1, genoketide A2 and prechrysophanol glucuronide are biosynthetic intermediates of the octaketide chrysophanol. They were isolated from the alkaliphilic strain Streptomyces sp. AK 671 together with the new metabolite chrysophanol glucuronide. The structures of the compounds were elucidated by mass spectrometry and NMR methods. Genoketide A2 exhibited a slight and prechrysophanol glucuronide a more pronounced inhibition of the proliferation of L5178y lymphoma cells.
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  • 9
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    Nature Publishing Group
    In:  Nature, 456 . pp. 489-492.
    Publikationsdatum: 2019-09-23
    Beschreibung: Predicting the evolution of climate over decadal timescales requires a quantitative understanding of the dynamics that govern the meridional overturning circulation (MOC)1. Comprehensive ocean measurement programmes aiming to monitor MOC variations have been established in the subtropical North Atlantic2, 3 (RAPID, at latitude 26.5° N, and MOVE, at latitude 16° N) and show strong variability on intraseasonal to interannual timescales. Observational evidence of longer-term changes in MOC transport remains scarce, owing to infrequent sampling of transoceanic sections over past decades4, 5. Inferences based on long-term sea surface temperature records, however, supported by model simulations, suggest a variability with an amplitude of plusminus1.5–3 Sv (1 Sv = 106 m3 s-1) on decadal timescales in the subtropics6. Such variability has been attributed to variations of deep water formation in the sub-arctic Atlantic, particularly the renewal rate of Labrador Sea Water7. Here we present results from a model simulation that suggest an additional influence on decadal MOC variability having a Southern Hemisphere origin: dynamic signals originating in the Agulhas leakage region at the southern tip of Africa. These contribute a MOC signal in the tropical and subtropical North Atlantic that is of the same order of magnitude as the northern source. A complete rationalization of observed MOC changes therefore also requires consideration of signals arriving from the south.
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  • 10
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    Nature Publishing Group
    In:  Nature Geoscience, 1 (1). pp. 14-15.
    Publikationsdatum: 2017-02-22
    Beschreibung: The relationship between carbon dioxide and climate over millions of years has been a source of controversy. Fossilized liverwort leaves can help illuminate both temperature and atmospheric carbon dioxide levels from 200 to 60 million years ago.
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  • 11
    Publikationsdatum: 2017-02-23
    Beschreibung: Despite similar physical properties, the Northern and Southern Atlantic subtropical gyres have different biogeochemical regimes. The Northern subtropical gyre, which is subject to iron deposition from Saharan dust1, is depleted in the nutrient phosphate, possibly as a result of iron-enhanced nitrogen fixation2. Although phosphate depleted, rates of carbon fixation in the euphotic zone of the North Atlantic subtropical gyre are comparable to those of the South Atlantic subtropical gyre3, which is not phosphate limited. Here we use the activity of the phosphorus-specific enzyme alkaline phosphatase to show potentially enhanced utilization of dissolved organic phosphorus occurring over much of the North Atlantic subtropical gyre. We find that during the boreal spring up to 30% of primary production in the North Atlantic gyre is supported by dissolved organic phosphorus. Our diagnostics and composite map of the surface distribution of dissolved organic phosphorus in the subtropical Atlantic Ocean reveal shorter residence times in the North Atlantic gyre than the South Atlantic gyre. We interpret the asymmetry of dissolved organic phosphorus cycling in the two gyres as a consequence of enhanced nitrogen fixation in the North Atlantic Ocean4, which forces the system towards phosphorus limitation. We suggest that dissolved organic phosphorus utilization may contribute to primary production in other phosphorus-limited ocean settings as well.
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  • 12
    Publikationsdatum: 2019-09-23
    Beschreibung: Piceamycin, a new macrolactam polyketide antibiotic, was detected by HPLC-diode array screening in extracts of Streptomyces sp. GB 4-2, which was isolated from the mycorrhizosphere of Norway spruce. The structure of piceamycin was determined by mass spectrometry and NMR experiments. It showed inhibitory activity against Gram-positive bacteria, selected human tumor cell lines and protein tyrosine phosphatase 1B. The Journal of Antibiotics (2009) 62, 513-518; doi:10.1038/ja.2009.64; published online 17 July 2009
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  • 13
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    Nature Publishing Group
    In:  Nature Geoscience, 2 (7). pp. 463-464.
    Publikationsdatum: 2015-07-10
    Beschreibung: Seafloor vents spewing mineral-rich plumes of hydrothermal fluid — termed black smokers — can persist at mid-ocean ridges for decades or longer. Earthquake data indicate that ongoing magma injection may determine their locations.
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  • 14
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    Nature Publishing Group
    In:  The ISME Journal, 1 (3). pp. 187-190.
    Publikationsdatum: 2020-05-11
    Beschreibung: Marine sponges (phylum Porifera) are among the oldest multicellular animals (metazoans), the sea's most prolific producers of bioactive metabolites, and of considerable ecological importance due to their abundance and ability to filter enormous volumes of seawater. In addition to these important attributes, sponge microbiology is now a rapidly expanding field.
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  • 15
    Publikationsdatum: 2020-10-26
    Beschreibung: Resolving flow geometry in the mantle wedge is central to understanding the thermal and chemical structure of subduction zones, subducting plate dehydration, and melting that leads to arc volcanism, which can threaten large populations and alter climate through gas and particle emission. Here we show that isotope geochemistry and seismic velocity anisotropy provide strong evidence for trench-parallel flow in the mantle wedge beneath Costa Rica and Nicaragua. This finding contradicts classical models, which predict trench-normal flow owing to the overlying wedge mantle being dragged downwards by the subducting plate. The isotopic signature of central Costa Rican volcanic rocks is not consistent with its derivation from the mantle wedge1, 2, 3 or eroded fore-arc complexes4 but instead from seamounts of the Galapagos hotspot track on the subducting Cocos plate. This isotopic signature decreases continuously from central Costa Rica to northwestern Nicaragua. As the age of the isotopic signature beneath Costa Rica can be constrained and its transport distance is known, minimum northwestward flow rates can be estimated (63–190 mm yr-1) and are comparable to the magnitude of subducting Cocos plate motion (approx85 mm yr-1). Trench-parallel flow needs to be taken into account in models evaluating thermal and chemical structure and melt generation in subduction zones.
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  • 16
    Publikationsdatum: 2019-09-23
    Beschreibung: In the context of gradual Cenozoic cooling, the timing of the onset of significant Northern Hemisphere glaciation 2.7 million years ago is consistent with Milankovitch's orbital theory, which posited that ice sheets grow when polar summertime insolation and temperature are low. However, the role of moisture supply in the initiation of large Northern Hemisphere ice sheets has remained unclear. The subarctic Pacific Ocean represents a significant source of water vapour to boreal North America, but it has been largely overlooked in efforts to explain Northern Hemisphere glaciation. Here we present alkenone unsaturation ratios and diatom oxygen isotope ratios from a sediment core in the western subarctic Pacific Ocean, indicating that 2.7 million years ago late-summer sea surface temperatures in this ocean region rose in response to an increase in stratification. At the same time, winter sea surface temperatures cooled, winter floating ice became more abundant and global climate descended into glacial conditions. We suggest that the observed summer warming extended into the autumn, providing water vapour to northern North America, where it precipitated and accumulated as snow, and thus allowed the initiation of Northern Hemisphere glaciation.
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  • 17
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    Nature Publishing Group
    In:  Nature Geoscience, 2 (4). pp. 243-244.
    Publikationsdatum: 2019-09-23
    Beschreibung: The enhanced Arctic warming over the past three decades is attracting much attention. Combining forward and inverse models with observations suggests that regional changes in aerosol concentrations have contributed significantly.
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  • 18
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    Nature Publishing Group
    In:  Nature, 244 (131). pp. 11-12.
    Publikationsdatum: 2018-03-02
    Beschreibung: STEP-LIKE structures in temperature and salinity beneath the Mediterranean water have been observed in the Eastern Atlantic1–6. In Fig. 1 we show the stations where steps have been found in the area to the west of Gibraltar. Salt fingering as a result of double diffusive processes has been suggested as a possible cause for the generation of such step-like structures7. During cruise No. 23 of RV Meteor in 1971 we intended to study the small scale features of such structures8. Some previous observations6 in August/September 1970 had revealed an extensive zone where a “thermohaline staircase” existed (Fig. 1). We therefore selected stations in this area and close to it for the proposed study. A high resolution in situ conductivity-temperature-depth meter of the “Kieler Multi-Meeressonde” type was used for the vertical profiling of temperature and salinity.
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  • 19
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    Nature Publishing Group
    In:  Nature, 453 . pp. 84-88.
    Publikationsdatum: 2020-02-18
    Beschreibung: The climate of the North Atlantic region exhibits fluctuations on decadal timescales that have large societal consequences. Prominent examples include hurricane activity in the Atlantic1, and surface-temperature and rainfall variations over North America2, Europe3 and northern Africa4. Although these multidecadal variations are potentially predictable if the current state of the ocean is known5, 6, 7, the lack of subsurface ocean observations8 that constrain this state has been a limiting factor for realizing the full skill potential of such predictions9. Here we apply a simple approach—that uses only sea surface temperature (SST) observations—to partly overcome this difficulty and perform retrospective decadal predictions with a climate model. Skill is improved significantly relative to predictions made with incomplete knowledge of the ocean state10, particularly in the North Atlantic and tropical Pacific oceans. Thus these results point towards the possibility of routine decadal climate predictions. Using this method, and by considering both internal natural climate variations and projected future anthropogenic forcing, we make the following forecast: over the next decade, the current Atlantic meridional overturning circulation will weaken to its long-term mean; moreover, North Atlantic SST and European and North American surface temperatures will cool slightly, whereas tropical Pacific SST will remain almost unchanged. Our results suggest that global surface temperature may not increase over the next decade, as natural climate variations in the North Atlantic and tropical Pacific temporarily offset the projected anthropogenic warming.
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  • 20
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    Nature Publishing Group
    In:  Nature Geoscience, 1 (7). pp. 423-424.
    Publikationsdatum: 2017-02-23
    Beschreibung: Ninety-five million years ago, ocean bottom waters were much warmer than at present. Some of this warmth could have come from the proto-North Atlantic's continental shelves after the balmy surface waters became increasingly salty through evaporation.
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  • 21
    Publikationsdatum: 2019-09-23
    Beschreibung: The transport of warm and salty Indian Ocean waters into the Atlantic Ocean—the Agulhas leakage—has a crucial role in the global oceanic circulation1 and thus the evolution of future climate. At present these waters provide the main source of heat and salt for the surface branch of the Atlantic meridional overturning circulation (MOC)2. There is evidence from past glacial-to-interglacial variations in foraminiferal assemblages3 and model studies4 that the amount of Agulhas leakage and its corresponding effect on the MOC has been subject to substantial change, potentially linked to latitudinal shifts in the Southern Hemisphere westerlies5. A progressive poleward migration of the westerlies has been observed during the past two to three decades and linked to anthropogenic forcing6, but because of the sparse observational records it has not been possible to determine whether there has been a concomitant response of Agulhas leakage. Here we present the results of a high-resolution ocean general circulation model7, 8 to show that the transport of Indian Ocean waters into the South Atlantic via the Agulhas leakage has increased during the past decades in response to the change in wind forcing. The increased leakage has contributed to the observed salinification9 of South Atlantic thermocline waters. Both model and historic measurements off South America suggest that the additional Indian Ocean waters have begun to invade the North Atlantic, with potential implications for the future evolution of the MOC.
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  • 22
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    Nature Publishing Group
    In:  Nature Geoscience, 1 . pp. 68-72.
    Publikationsdatum: 2019-09-23
    Beschreibung: The early oceanographic history of the Arctic Ocean is important in regulating, and responding to, climatic changes. However, constraints on its oceanographic history preceding the Quaternary (the past 1.8 Myr) have become available only recently, because of the difficulties associated with obtaining continuous sediment records in such a hostile setting. Here, we use the neodymium isotope compositions of two sediment cores recovered near the North Pole to reconstruct over the past approx15 Myr the sources contributing to Arctic Intermediate Water, a water mass found today at depths of 200 to 1,500 m. We interpret high neodymium ratios for the period between 15 and 2 Myr ago, and for the glacial periods thereafter, as indicative of weathering input from the Siberian Putoranan basalts into the Arctic Ocean. Arctic Intermediate Water was then derived from brine formation in the Eurasian shelf regions, with only a limited contribution of intermediate water from the North Atlantic. In contrast, the modern circulation pattern, with relatively high contributions of North Atlantic Intermediate Water and negligible input from brine formation, exhibits low neodymium isotope ratios and is typical for the interglacial periods of the past 2 Myr. We suggest that changes in climatic conditions and the tectonic setting were responsible for switches between these two modes.
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  • 23
    Publikationsdatum: 2019-09-23
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  • 24
    Publikationsdatum: 2017-02-22
    Beschreibung: Organic-rich sedimentary units called sapropels have formed repeatedly in the eastern Mediterranean Sea, in response to variations of solar radiation. Sapropel formation is due to a change either in the flux of organic matter to the sea floor from productivity changes or in preservation by bottom-water oxygen levels. However, the relative importance of surface-ocean productivity versus deep-water preservation for the formation of these organic-rich shale beds is still being debated, and conflicting interpretations are often invoked1, 2, 3, 4, 5, 6, 7. Here we analyse at high resolution the differences in the composition of the most recent sapropel, S1, in a suite of cores covering the entire eastern Mediterranean basin. We demonstrate that during the 4,000 years of sapropel formation, surface-water salinity was reduced and the deep eastern Mediterranean Sea, below 1,800 m depth, was devoid of oxygen. This resulted in the preferential basin-wide preservation of sapropel S1 with different characteristics above and below 1,800 m depth as a result of different redox conditions. We conclude that climate-induced stratification of the ocean may therefore contribute to enhanced preservation of organic matter in sapropels and potentially also in black shales.
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  • 25
    Publikationsdatum: 2019-07-03
    Beschreibung: The history of the Arctic Ocean during the Cenozoic era (0–65 million years ago) is largely unknown from direct evidence. Here we present a Cenozoic palaeoceanographic record constructed from 〉400 m of sediment core from a recent drilling expedition to the Lomonosov ridge in the Arctic Ocean. Our record shows a palaeoenvironmental transition from a warm 'greenhouse' world, during the late Palaeocene and early Eocene epochs, to a colder 'icehouse' world influenced by sea ice and icebergs from the middle Eocene epoch to the present. For the most recent approx14 Myr, we find sedimentation rates of 1–2 cm per thousand years, in stark contrast to the substantially lower rates proposed in earlier studies; this record of the Neogene reveals cooling of the Arctic that was synchronous with the expansion of Greenland ice (approx3.2 Myr ago) and East Antarctic ice (approx14 Myr ago). We find evidence for the first occurrence of ice-rafted debris in the middle Eocene epoch (approx45 Myr ago), some 35 Myr earlier than previously thought; fresh surface waters were present at approx49 Myr ago, before the onset of ice-rafted debris. Also, the temperatures of surface waters during the Palaeocene/Eocene thermal maximum (approx55 Myr ago) appear to have been substantially warmer than previously estimated. The revised timing of the earliest Arctic cooling events coincides with those from Antarctica, supporting arguments for bipolar symmetry in climate change.
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  • 26
    Publikationsdatum: 2019-09-23
    Beschreibung: Deep-water formation in the northern North Atlantic Ocean and the Arctic Ocean is a key driver of the global thermohaline circulation and hence also of global climate1. Deciphering the history of the circulation regime in the Arctic Ocean has long been prevented by the lack of data from cores of Cenozoic sediments from the Arctic's deep-sea floor. Similarly, the timing of the opening of a connection between the northern North Atlantic and the Arctic Ocean, permitting deep-water exchange, has been poorly constrained. This situation changed when the first drill cores were recovered from the central Arctic Ocean2. Here we use these cores to show that the transition from poorly oxygenated to fully oxygenated ('ventilated') conditions in the Arctic Ocean occurred during the later part of early Miocene times. We attribute this pronounced change in ventilation regime to the opening of the Fram Strait. A palaeo-geographic and palaeo-bathymetric reconstruction of the Arctic Ocean, together with a physical oceanographic analysis of the evolving strait and sill conditions in the Fram Strait, suggests that the Arctic Ocean went from an oxygen-poor 'lake stage', to a transitional 'estuarine sea' phase with variable ventilation, and finally to the fully ventilated 'ocean' phase 17.5 Myr ago. The timing of this palaeo-oceanographic change coincides with the onset of the middle Miocene climatic optimum3, although it remains unclear if there is a causal relationship between these two events.
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  • 27
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    Nature Publishing Group
    In:  Nature, 434 . E2.
    Publikationsdatum: 2017-03-10
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  • 28
    Publikationsdatum: 2017-03-06
    Beschreibung: Diatoms are photosynthetic secondary endosymbionts found throughout marine and freshwater environments, and are believed to be responsible for around one-fifth of the primary productivity on Earth1, 2. The genome sequence of the marine centric diatom Thalassiosira pseudonana was recently reported, revealing a wealth of information about diatom biology3, 4, 5. Here we report the complete genome sequence of the pennate diatom Phaeodactylum tricornutum and compare it with that of T. pseudonana to clarify evolutionary origins, functional significance and ubiquity of these features throughout diatoms. In spite of the fact that the pennate and centric lineages have only been diverging for 90 million years, their genome structures are dramatically different and a substantial fraction of genes (approx40%) are not shared by these representatives of the two lineages. Analysis of molecular divergence compared with yeasts and metazoans reveals rapid rates of gene diversification in diatoms. Contributing factors include selective gene family expansions, differential losses and gains of genes and introns, and differential mobilization of transposable elements. Most significantly, we document the presence of hundreds of genes from bacteria. More than 300 of these gene transfers are found in both diatoms, attesting to their ancient origins, and many are likely to provide novel possibilities for metabolite management and for perception of environmental signals. These findings go a long way towards explaining the incredible diversity and success of the diatoms in contemporary oceans.
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  • 29
    Publikationsdatum: 2019-09-23
    Beschreibung: The tectonically driven closure of tropical seaways during the Pliocene epoch (approx5–2 million years (Myr) ago) altered ocean circulation and affected the evolution of climate. Plate tectonic reconstructions show that the main reorganization of one such seaway, the Indonesian Gateway, occurred between 4 and 3 Myr ago. Model simulations have suggested that this would have triggered a switch in the source of waters feeding the Indonesian throughflow into the Indian Ocean, from the warm salty waters of the South Pacific Ocean to the cool and relatively fresh waters of the North Pacific Ocean. Here we use paired measurements of the delta18O and Mg/Ca ratios of planktonic foraminifera to reconstruct the thermal structure of the eastern tropical Indian Ocean from 5.5 to 2 Myr ago. We find that sea surface conditions remained relatively stable throughout the interval, whereas subsurface waters freshened and cooled by about 4 °C between 3.5 and 2.95 Myr ago. We suggest that the restriction of the Indonesian Gateway led to the cooling and shoaling of the thermocline in the tropical Indian Ocean. We conclude that this tectonic reorganization contributed to the global shoaling of the thermocline recorded during the Pliocene epoch, possibly contributing to the development of the equatorial eastern Pacific cold tongue.
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  • 30
    Publikationsdatum: 2017-02-22
    Beschreibung: Oceanic fixed-nitrogen concentrations are controlled by the balance between nitrogen fixation and denitrification. A number of factors, including iron limitation, can restrict nitrogen fixation, introducing the potential for decoupling of nitrogen inputs and losses. Such decoupling could significantly affect the oceanic fixed-nitrogen inventory and consequently the biological component of ocean carbon storage and hence air–sea partitioning of carbon dioxide. However, the extent to which nutrients limit nitrogen fixation in the global ocean is uncertain. Here, we examined rates of nitrogen fixation and nutrient concentrations in the surface waters of the Atlantic Ocean along a north–south 10,000 km transect during October and November 2005. We show that rates of nitrogen fixation were markedly higher in the North Atlantic compared with the South Atlantic Ocean. Across the two basins, nitrogen fixation was positively correlated with dissolved iron and negatively correlated with dissolved phosphorus concentrations. We conclude that inter-basin differences in nitrogen fixation are controlled by iron supply rather than phosphorus availability. Analysis of the nutrient content of deep waters suggests that the fixed nitrogen enters North Atlantic Deep Water. Our study thus supports the suggestion that iron significantly influences nitrogen fixation5, and that subsequent interactions with ocean circulation patterns contribute to the decoupling of nitrogen fixation and loss.
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  • 31
    Publikationsdatum: 2017-02-22
    Beschreibung: Observations show a significant intensification of the Southern Hemisphere westerlies, the prevailing winds between the latitudes of 30° and 60° S, over the past decades. A continuation of this intensification trend is projected by climate scenarios for the twenty-first century. The response of the Antarctic Circumpolar Current and the carbon sink in the Southern Ocean to changes in wind stress and surface buoyancy fluxes is under debate. Here we analyse the Argo network of profiling floats and historical oceanographic data to detect coherent hemispheric-scale warming and freshening trends that extend to depths of more than 1,000 m. The warming and freshening is partly related to changes in the properties of the water masses that make up the Antarctic Circumpolar Current, which are consistent with the anthropogenic changes in heat and freshwater fluxes suggested by climate models. However, we detect no increase in the tilt of the surfaces of equal density across the Antarctic Circumpolar Current, in contrast to coarse-resolution model studies. Our results imply that the transport in the Antarctic Circumpolar Current and meridional overturning in the Southern Ocean are insensitive to decadal changes in wind stress.
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  • 32
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    Nature Publishing Group
    In:  Nature, 300 (5889). pp. 245-246.
    Publikationsdatum: 2018-03-08
    Beschreibung: A subtropical front was observed in the area south and southeast of the Azores during cruises of FS Meteor and FS Poseidon in early 1982. The front has a basically west–east extension, with considerable meandering observed. Meso-scale eddies are found on both sides. The overall flow pattern corresponds to earlier results on geopotential differences in the upper northeast Atlantic, but the baroclinic transport of the order of 107 m3 s−1 is found to be concentrated in a 60-km wide jet. We suggest here that the current band is part of the gyre circulation, resulting from a branching of the North Atlantic Current.
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  • 33
    Publikationsdatum: 2019-09-23
    Beschreibung: Caboxamycin, a new benzoxazole antibiotic, was detected by HPLC-diode array screening in extracts of the marine strain Streptomyces sp. NTK 937, which was isolated from deep-sea sediment collected in the Canary Basin. The structure of caboxamycin was determined by mass spectrometry, NMR experiments and X-ray analysis. It showed inhibitory activity against Gram-positive bacteria, selected human tumor cell lines and the enzyme phosphodiesterase.
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  • 34
    Publikationsdatum: 2019-01-21
    Beschreibung: Circumpolar surface waters dominate the circulation of the Southern Ocean and sustain one of the ocean's largest standing stocks of biomass thereby producing a significant output of biogenic components, mainly diatoms, to the bottom sediments. Generally transit of biogenic matter from the sea surface to the sea floor affects nutrient regeneration fuels benthic life and transfers signals to the sediment record1–5. Reliable quantification of the relationship between biological production, fractionation of skeletal and tissue components and bottom sediment accumulation depends on direct vertical flux measurements from sediment trap deployments6–9, which have proved to be most scientifically productive10–13. We now present data on vertical mass fluxes from the Southern Ocean and evidence for strong biogeochemical fractionation between organic carbon-, nitrogen- and phosphorus-containing compounds, siliceous and calcareous skeletal remains, and refractory aluminosilicates.
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  • 35
    Publikationsdatum: 2016-09-02
    Beschreibung: Analysis of aeolo-marine dust deposits in the subtropical eastern Atlantic enables the strength of the major wind patterns during the late Quaternary to be evaluated and gives an insight into the climate of North Africa.
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  • 36
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    Nature Publishing Group
    In:  Nature, 238 (5364). pp. 405-406.
    Publikationsdatum: 2016-09-14
    Beschreibung: In the southern hemisphere, female and young male sperm whales (up to about 39 feet long) are not normally found in higher latitudes than 40° S while large males occur in Antarctic waters1–3; clearly many large bulls must migrate from the breeding areas into colder regions. Evidence of the return of large bulls to lower latitudes rests upon marking them in the Antarctic4 or external infestation by Antarctic Cocconeis or Cyamus 5. Only a single mark5 has been recovered which provides direct evidence for the return north from Antarctic waters. This mark (USSR No. 650203) was fired on December 25, 1967, at 62° 22′ S 26° 25′ E and the whale was killed on May 13, 1968, off Durban. The small size of the male concerned (35 feet at death) makes this record rather surprising although Jonsgård6 did mention that the smallest whales from Antarctic waters were about 35 feet. Marking can provide information on only a small part of the whale population at considerable cost, freshness of the whale restricts the value of infestation as an indicator but the study of food remnants in sperm whale stomachs provides another method without these disadvantages.
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  • 37
    Publikationsdatum: 2019-09-23
    Beschreibung: Gombapyrones A–D, new members of the α-pyrone family of secondary metabolites, were produced by Streptomyces griseoruber Acta 3662, which was isolated from bamboo tree rhizosphere. The strain was characterized by its morphological and chemotaxonomical features and by 16S rDNA sequencing as S. griseobuber. The gombapyrone structures were determined by mass spectrometry and by NMR experiments, and were found to have an inhibitory activity against protein tyrosine phosphatase 1B and glycogen synthase kinase 3β.
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  • 38
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    Nature Publishing Group
    In:  Nature, 454 . pp. 46-47.
    Publikationsdatum: 2019-09-23
    Beschreibung: Rising levels of atmospheric carbon dioxide lead to acidification of the oceans. A site in the Mediterranean, naturally carbonated by under-sea volcanoes, provides clues to the possible effects on marine ecosystems.
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  • 39
    Publikationsdatum: 2017-02-22
    Beschreibung: Subduction zones are often characterized by wedge-shaped sedimentary complexes—called accretionary prisms—that form when sediments are scraped off the subducting plate and added to the overriding plate. Large, landward-dipping thrust faults can cut through such a prism: these faults, known as 'megasplay faults'1, 2, originate near the top of the subducting plate and terminate at the shallow, landward edge of the prism1, 3, 4, 5, 6. Megasplay faults have been the subject of numerous geological and geophysical studies4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, but their initiation and evolution through time remains poorly constrained. Here we combine seismic reflection data from the Nankai accretionary wedge with geological data collected by the Integrated Ocean Drilling Program (IODP) and find that the splay fault cutting this wedge initiated approx1.95 Million years (Myr) ago in the lower part of the prism as an out-of-sequence thrust (OOST). After an initial phase of high activity, the movement along the fault slowed down, but uplift and reactivation of the fault resumed about 1.55 Myr ago. The alternating periods of high and low activity along the splay fault that we document hint at episodic changes in the mechanical stability of accretionary prisms.
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  • 40
    Publikationsdatum: 2016-05-25
    Beschreibung: The ecological niche of nitrate-storing Beggiatoa, and their contribution to the removal of sulfide were investigated in coastal sediment. With microsensors a clear suboxic zone of 2-10cm thick was identified, where neither oxygen nor free sulfide was detectable. In this zone most of the Beggiatoa were found, where they oxidize sulfide with internally stored nitrate. The sulfide input into the suboxic zone was dominated by an upward sulfide flux from deeper sediment, whereas the local production in the suboxic zone was much smaller. Despite their abundance, the calculated sulfide-oxidizing capacity of the Beggiatoa could account for only a small fraction of the total sulfide removal in the sediment. Consequently, most of the sulfide flux into the suboxic layer must have been removed by chemical processes, mainly by precipitation with Fe2+ and oxidation by Fe(III), which was coupled with a pH increase. The free Fe2+ diffusing upwards was oxidized by Mn(IV), resulting in a strong pH decrease. The nitrate storage capacity allows Beggiatoa to migrate randomly up and down in anoxic sediments with an accumulated gliding distance of 4m before running out of nitrate. We propose that the steep sulfide gradient and corresponding high sulfide flux, a typical characteristic of Beggiatoa habitats, is not needed for their metabolic performance, but rather used as a chemotactic cue by the highly motile filaments to avoid getting lost at depth in the sediment. Indeed sulfide is a repellant for Beggiatoa.
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  • 41
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    Nature Publishing Group
    In:  Nature, 459 (7244). pp. 166-167.
    Publikationsdatum: 2019-03-08
    Beschreibung: As scientists discover more about the genomes of marine microorganisms, new views of their physiology and ecosystem networks are opening up, explain Alexandra Z. Worden and Darcy McRose. "Alien Ocean: Anthropological Voyages in Microbial Seas by Stefan Helmreich University of California Press: 2009. 464 pp."
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  • 42
    Publikationsdatum: 2020-01-07
    Beschreibung: Large uncertainties remain in the current and future contribution to sea level rise from Antarctica. Climate warming may increase snowfall in the continent’s interior1,2,3, but enhance glacier discharge at the coast where warmer air and ocean temperatures erode the buttressing ice shelves4,5,6,7,8,9,10,11. Here, we use satellite interferometric synthetic-aperture radar observations from 1992 to 2006 covering 85% of Antarctica’s coastline to estimate the total mass flux into the ocean. We compare the mass fluxes from large drainage basin units with interior snow accumulation calculated from a regional atmospheric climate model for 1980 to 2004. In East Antarctica, small glacier losses in Wilkes Land and glacier gains at the mouths of the Filchner and Ross ice shelves combine to a near-zero loss of 4±61 Gt yr−1. In West Antarctica, widespread losses along the Bellingshausen and Amundsen seas increased the ice sheet loss by 59% in 10 years to reach 132±60 Gt yr−1 in 2006. In the Peninsula, losses increased by 140% to reach 60±46 Gt yr−1 in 2006. Losses are concentrated along narrow channels occupied by outlet glaciers and are caused by ongoing and past glacier acceleration. Changes in glacier flow therefore have a significant, if not dominant impact on ice sheet mass balance.
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  • 43
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    Unbekannt
    Nature Publishing Group
    In:  The ISME Journal, 3 (1). pp. 4-12.
    Publikationsdatum: 2019-09-24
    Beschreibung: Our understanding of the composition and activities of microbial communities from diverse habitats on our planet has improved enormously during the past decade, spurred on largely by advances in molecular biology. Much of this research has focused on the bacteria, and to a lesser extent on the archaea and viruses, because of the relative ease with which these assemblages can be analyzed and studied genetically. In contrast, single-celled, eukaryotic microbes (the protists) have received much less attention, to the point where one might question if they have somehow been demoted from the position of environmentally important taxa. In this paper, we draw attention to this situation and explore several possible (some admittedly lighthearted) explanations for why these remarkable and diverse microbes have remained largely overlooked in the present era of the microbe. © 2009 International Society for Microbial Ecology All rights reserved.
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  • 44
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    Nature Publishing Group
    In:  Nature, 287 (5783). pp. 628-630.
    Publikationsdatum: 2016-11-15
    Beschreibung: Statoliths of cephalopods are small, hard calcareous stones which lie within the cartilaginous skulls of octopods, sepioids and teuthoids1. Fossil statoliths, clearly belonging to genera which are alive today, have previously been described from 11 Cenozoic deposits spanning from the Eocene to the Pleistocene in North America2–5. Such statoliths are of particular interest because they provide a means of studying the evolution of living cephalopod groups which have no calcareous shells, including the cosmopolitan and numerous teuthoids and octopods. Here, the first cephalopod statoliths to be recognized in European deposits are described and identified as Loligo sp. They are compared with the North American fossil Loligo species and statoliths removed from the two living Loligo species of Europe.
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  • 45
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    Nature Publishing Group
    In:  Nature, 305 (5933). pp. 403-407.
    Publikationsdatum: 2016-11-23
    Beschreibung: Basalts from the Reykjanes Ridge contain noble gases delivered from the non-degassed lower mantle by the Iceland plume. These lower mantle gases are thought to be a mixture of planetary and solar components, as would be expected if the Earth accreted from fine silicate particles.
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  • 46
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    Nature Publishing Group
    In:  Nature, 433 (7023). p. 212.
    Publikationsdatum: 2021-08-16
    Beschreibung: Sexual mimicry among animals is widespread, but does it impart a fertilization advantage in the widely accepted ‘sneak–guard’ model of sperm competition? Here we describe field results in which a dramatic facultative switch in sexual phenotype by sneaker-male cuttlefish leads to immediate fertilization success, even in the presence of the consort male. These results are surprising, given the high rate at which females reject copulation attempts by males, the strong mate-guarding behaviour of consort males, and the high level of sperm competition in this complex mating system
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  • 47
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    Nature Publishing Group
    In:  Nature, 438 (7070). p. 929.
    Publikationsdatum: 2021-08-20
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  • 48
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    Nature Publishing Group
    In:  Nature, 459 . pp. 243-248.
    Publikationsdatum: 2017-03-06
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  • 49
    Publikationsdatum: 2019-09-23
    Beschreibung: The oceans have absorbed nearly half of the fossil-fuel carbon dioxide (CO2) emitted into the atmosphere since pre-industrial times1, causing a measurable reduction in seawater pH and carbonate saturation2. If CO2 emissions continue to rise at current rates, upper-ocean pH will decrease to levels lower than have existed for tens of millions of years and, critically, at a rate of change 100 times greater than at any time over this period3. Recent studies have shown effects of ocean acidification on a variety of marine life forms, in particular calcifying organisms4, 5, 6. Consequences at the community to ecosystem level, in contrast, are largely unknown. Here we show that dissolved inorganic carbon consumption of a natural plankton community maintained in mesocosm enclosures at initial CO2 partial pressures of 350, 700 and 1,050 μatm increases with rising CO2. The community consumed up to 39% more dissolved inorganic carbon at increased CO2 partial pressures compared to present levels, whereas nutrient uptake remained the same. The stoichiometry of carbon to nitrogen drawdown increased from 6.0 at low CO2 to 8.0 at high CO2, thus exceeding the Redfield carbon:nitrogen ratio of 6.6 in today’s ocean7. This excess carbon consumption was associated with higher loss of organic carbon from the upper layer of the stratified mesocosms. If applicable to the natural environment, the observed responses have implications for a variety of marine biological and biogeochemical processes, and underscore the importance of biologically driven feedbacks in the ocean to global change.
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  • 50
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    Nature Publishing Group
    In:  Nature, 458 (7240). pp. 881-884.
    Publikationsdatum: 2017-03-06
    Beschreibung: Widespread evidence of a +4–6-m sea-level highstand during the last interglacial period (Marine Isotope Stage 5e) has led to warnings that modern ice sheets will deteriorate owing to global warming and initiate a rise of similar magnitude by ad 2100 (ref. 1). The rate of this projected rise is based on ice-sheet melting simulations and downplays discoveries of more rapid ice loss2, 3. Knowing the rate at which sea level reached its highstand during the last interglacial period is fundamental in assessing if such rapid ice-loss processes could lead to future catastrophic sea-level rise. The best direct record of sea level during this highstand comes from well-dated fossil reefs in stable areas4, 5, 6. However, this record lacks both reef-crest development up to the full highstand elevation, as inferred7 from widespread intertidal indicators at +6 m, and a detailed chronology, owing to the difficulty of replicating U-series ages on submillennial timescales8. Here we present a complete reef-crest sequence for the last interglacial highstand and its U-series chronology from the stable northeast Yucatán peninsula, Mexico. We find that reef development during the highstand was punctuated by reef-crest demise at +3 m and back-stepping to +6 m. The abrupt demise of the lower-reef crest, but continuous accretion between the lower-lagoonal unit and the upper-reef crest, allows us to infer that this back-stepping occurred on an ecological timescale and was triggered by a 2–3-m jump in sea level. Using strictly reliable 230Th ages of corals from the upper-reef crest, and improved stratigraphic screening of coral ages from other stable sites, we constrain this jump to have occurred approx121 kyr ago and conclude that it supports an episode of ice-sheet instability during the terminal phase of the last interglacial period.
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  • 51
    Publikationsdatum: 2017-03-10
    Beschreibung: The tropics have been suggested as the drivers of global ocean and atmosphere circulation and biogeochemical cycling during the extreme warmth of the Cretaceous period1, 2; but the links between orbital forcing, freshwater runoff and the biogeochemistry of continental margins in extreme greenhouse conditions are not fully understood. Here we present Cretaceous records of geochemical tracers for freshwater runoff obtained from a sediment core off the Ivory Coast that indicate that alternating periods of arid and humid African climate were driven by orbital precession. Our simulations of the precession-driven patterns of river discharge with a global climate model suggest that ocean anoxia and black shale sedimentation were directly caused by high river discharge, and occurred specifically when the northern equinox coincided with perihelion (the minimum distance between the Sun and the Earth). We conclude that, in a warm climate, the oceans off tropical continental margins respond rapidly and sensitively to even modest changes in river discharge.
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  • 52
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    Nature Publishing Group
    In:  Nature Geoscience, 1 . pp. 2-3.
    Publikationsdatum: 2019-09-23
    Beschreibung: The Intergovernmental Panel for Climate Change has convinced the public that climate change is real. To tackle it, the panel needs complementary climate services that provide continuous climate information for all regions and the globe.
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  • 53
    Publikationsdatum: 2015-01-22
    Beschreibung: Permafrost-affected soils of the Siberian Arctic were investigated with regard to identification of nitrite oxidizing bacteria active at low temperature. Analysis of the fatty acid profiles of enrichment cultures grown at 4°C, 10°C and 17°C revealed a pattern that was different from that of known nitrite oxidizers but was similar to fatty acid profiles of Betaproteobacteria. Electron microscopy of two enrichment cultures grown at 10°C showed prevalent cells with a conspicuous ultrastructure. Sequence analysis of the 16S rRNA genes allocated the organisms to a so far uncultivated cluster of the Betaproteobacteria, with Gallionella ferruginea as next related taxonomically described organism. The results demonstrate that a novel genus of chemolithoautotrophic nitrite oxidizing bacteria is present in polygonal tundra soils and can be enriched at low temperatures up to 17°C. Cloned sequences with high sequence similarities were previously reported from mesophilic habitats like activated sludge and therefore an involvement of this taxon in nitrite oxidation in nonarctic habitats is suggested. The presented culture will provide an opportunity to correlate nitrification with nonidentified environmental clones in moderate habitats and give insights into mechanisms of cold adaptation. We propose provisional classification of the novel nitrite oxidizing bacterium as 'Candidatus Nitrotoga arctica'.
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  • 54
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    Nature Publishing Group
    In:  Nature, 303 (5916). pp. 422-423.
    Publikationsdatum: 2019-04-16
    Beschreibung: Strandings of the giant squid, Architeuthis monachus (Steen-strup), have always stirred attention because of the rarity and enormous size of these cephalopods. These animals have never been observed in their natural habitat and little is known about their physiology and ecology. Stranding of giant squids in Newfoundland waters has been correlated with the inflow of warm water, suggesting that increased temperature may be causing their death1. Squids have also been carried to the Norwegian coast with the warm North Atlantic current2 and on 23 August 1982 a live specimen was caught off Radöy near Bergen, Norway (Fig. 1). This catch gave an unprecedented opportunity to study the effects of temperature on the oxygen binding properties of blood from the giant squid. The present finding of an excess of a fourfold decrease in O2 affinity when temperature is increased from 6.4 to 15°C strongly suggests that giant squids may suffocate from arterial desaturation when increased ambient temperatures are experierced.
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  • 55
    Publikationsdatum: 2023-01-31
    Beschreibung: Palaeoclimate records and numerical model simulations indicate that changes in tropical and subtropical sea surface temperatures and in the annual average position of the intertropical convergence zone are linked to high-latitude climate changes on millennial to glacial–interglacial timescales. It has recently been suggested that cooling in the high latitudes associated with abrupt climate-change events is evident primarily during the northern hemisphere winter, implying increased seasonality at these times8. However, it is unclear whether such a seasonal bias also exists for the low latitudes. Here we analyse the Mg/Ca ratios of surface-dwelling foraminifera to reconstruct sea surface temperatures in the northeastern Gulf of Mexico for the past 300,000 years. We suggest that sea surface temperatures are controlled by the migration of the northern boundary of the Atlantic Warm Pool, and hence the position of the intertropical convergence zone during boreal summer, and are relatively insensitive to winter conditions. Our results suggest that summer Atlantic Warm Pool expansion is primarily affected by glacial–interglacial variability and low-latitude summer insolation. Because a clear signature of rapid climate-change events, such as the Younger Dryas cold event, is lacking in our record, we conclude that high-latitude events seem to influence only the winter Caribbean climate conditions, consistent with the hypothesis of extreme northern-hemisphere seasonality during abrupt cooling events.
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  • 56
    Publikationsdatum: 2022-05-26
    Beschreibung: © 2008 Nature Publishing Group. This article is distributed under the terms of the Creative Commons Attribution-Noncommercial-Share Alike license. The definitive version was published in Nature Biotechnology 26 (2008): 909-915, doi:10.1038/nbt.1482.
    Beschreibung: Plant-parasitic nematodes are major agricultural pests worldwide and novel approaches to control them are sorely needed. We report the draft genome sequence of the root-knot nematode Meloidogyne incognita, a biotrophic parasite of many crops, including tomato, cotton and coffee. Most of the assembled sequence of this asexually reproducing nematode, totaling 86 Mb, exists in pairs of homologous but divergent segments. This suggests that ancient allelic regions in M. incognita are evolving toward effective haploidy, permitting new mechanisms of adaptation. The number and diversity of plant cell wall–degrading enzymes in M. incognita is unprecedented in any animal for which a genome sequence is available, and may derive from multiple horizontal gene transfers from bacterial sources. Our results provide insights into the adaptations required by metazoans to successfully parasitize immunocompetent plants, and open the way for discovering new antiparasitic strategies.
    Beschreibung: SCRI laboratory (V.C.B. and J.T.J.) received funding from the Scottish Government. This work benefited from links funded via COST Action 872. G.V.M. and V.L. are supported by ARC, CNRS, EMBO, MENRT and Region Rhone-Alpes. G.V.M., M.R.-R. and V.L. are also funded by the EU Cascade Network of Excellence and the integrated project Crescendo. M.-C.C. is supported by MENRT.
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  • 57
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 772-772 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] Washington New drugs may be approved for sale in the United States solely on the basis of foreign data under a proposed reorganization of the Food and Drug Administration (PDA) new drug application process. One effect may be to facilitate the entry of drugs developed abroad into the US market. ...
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  • 58
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 779-780 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] IN recent years, optical bistability has been a subject of intense research in quantum electronics because of its potential usefulness in optical data processing and all-optical logic and computing systems1. There has already been a conference on the topic2, and at the Xllth International Quantum ...
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  • 59
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 783-788 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] Observations of the hot interstellar gas (T ≫ 104 K) are numerous and imply that the temperatures of substantial amounts of the disk gas to be 2–3 × 105 K and of the halo gas to be 8 × 104 K, but the theoretical models to explain the ...
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  • 60
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 807-810 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] Radiogenic 129Xe has been observed in samples from the Earth's mantle, but the abundance pattern of the eight nonradiogenic isotopes is atmospheric rather than chondritic6. Terrestrial' Xe will therefore be used instead of 'atmospheric Xe' in referring to the relative abundances of the ...
    Materialart: Digitale Medien
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  • 61
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 810-812 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] The presence of residual entropy implies a lack of thermal equilibrium in the crystal below a certain temperature. In fact, we have observed relaxational heat-capacity anomalies of - 100 K for ordinary ice5 and 115 K for heavy ice6, and have studied the associated enthalpy relaxation by subjecting ...
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  • 62
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 788-793 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] Powerful extragalactic radio sources may all be members of a single family in which those showing superluminal behaviour are the ones in which a relativistic jet is directed towards the observer. The superluminal sources are shown to have extended radio structures the form of which is consistent ...
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  • 63
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 803-805 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] Briefly, the Crab consists of a pulsar (assumed here to have a mass of ^lAM) and a nebula mass of 1.2-3.0M (refs 5,6) which has a helium overabundance of l.6〈XHc/XH〈S (where X is an element's mass fraction). The oxygen abundance (X0) is -0.003 (refs 5, 6), which is less than the solar value ...
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  • 64
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 843-843 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] THE prosimians, commonly referred to as "lower primates", can be loosely regarded as representing a primitive grade closer to the ancestral primate condition than the modern monkeys and apes. For this reason, any study of primate evolutionary biology is particularly dependent upon an understanding ...
    Materialart: Digitale Medien
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  • 65
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 667-667 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] Hurrah, the long recession is coming to an end. That is the simplest interpretation of what has happened in the past few weeks on the international stock markets, Wall Street in particular. For if people are willing once again enthusiastically to invest in the shares of industrial corporations ...
    Materialart: Digitale Medien
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  • 66
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 668-669 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] Sweden's Social Democratic Party was returned to power last month with an election platform that included a major commitment to science, higher education and technical research. The first actions of the new government, however, were to devalue the krona and to announce the guidelines of a new ...
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  • 67
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 670-670 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] The World Health Organization (WHO) Special Programme on Research and Training in Tropical Diseases has done well during its first five years of operation, according to the report of an external review committee set up by Dr D.E. Bell of the Harvard School of Public Health at the instance of the ...
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  • 68
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] The affected males in the pedigree shown in Fig. 1 have X-linked ichthyosis13 and complete deficiency of microsomal STS activity, based on assays using cholesterol sulphate and dehydroepiandrosterone sulphate (DHEAS) as steroid substrates (Tables 2, 3). Heterozygotes II-4, II-7 and II-8 are ...
    Materialart: Digitale Medien
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  • 69
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 671-671 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] Mr Edward Heath, the former Conservative Prime Minister, fresh from his denunciation earlier this month of government economic policy, last week broadened his attack on his party's government to the field of higher education. Speaking at the London School of Hygiene and Tropical Medicine, he ...
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  • 70
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 672-672 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] The French construction programme for nuclear reactors may be halved in 1984 and 1985, if budget-conscious elements in the government have their way. The reason: a ballooning government deficit and borrowing requirement, immense debts of FF120,000 million (£10,000 million) at Electricite de ...
    Materialart: Digitale Medien
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  • 71
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 677-678 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] ANTARCTICA represents a vast island remote from the other continents of the Southern Hemisphere. Most of the continent is covered by several kilometres of ice and the total ice-free area is very small. On the high central plateau the air is the cleanest in the world and the impurity content of the ...
    Materialart: Digitale Medien
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  • 72
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 680-681 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] MANY red-dwarf stars exhibit rotational light-curve modulation (the BY Draconis phenomenon) and flaring behaviour in the optical and radio regions of the spectrum (the UV Ceti phenomenon). Within the past decade, improved detectors, satellites and radio interferometry have led to a revolution in ...
    Materialart: Digitale Medien
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  • 73
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 698-702 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] A 12-kilobase DNA sequence has been identified in the maize mitochondrial genome which is homologous to part of the inverted repeat of the maize chloroplast genome. In chloroplasts the sequence contains a 16S rRNA gene, and also the coding sequences for tRNAIle and ...
    Materialart: Digitale Medien
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  • 74
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 708-710 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] CaTiSiO5 glasses were prepared by melting an intimately mixed charge of calcium carbonate, titanium dioxide and silica at 1,450 C for 1 h, followed by casting 1-cm diameter cylinders in stainless steel moulds. The tendency of the glass to crystallize or phase separate was avoided by keeping the ...
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  • 75
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 707-708 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] The crystalline phases of zirconium phosphate have layer structures similar to 2:1 clay minerals11'13. The crystalline phase with a composition Zr(HPO4)2 * H2O is called a-zirconium phosphate (a-ZrP) while Zr(HPO4)2 o 2H2O is called y-zirconium phosphate (y-ZrP). (The extensive literature on ...
    Materialart: Digitale Medien
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  • 76
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 718-720 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] The distinctive characteristics of the volcanoes ringing the great Pacific Basin and lining the Java-Sumatra arc were recognized long before the current ideas that relate them to subducting lithospheric plates found favour. Nevertheless, it was the notion of a dynamic mantle that gave the study of ...
    Materialart: Digitale Medien
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  • 77
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 730-732 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] For these studies we selected the opioid peptides morphicep-tin and leucine-enkephalin. Leucine-enkephalin (Leu-enke-phalin) is about 1,000-fold more potent than morphiceptin at 8 -receptors whereas the two ligands are approximately equipotent at pt-receptors11'17'18'22'29. Preparation of mouse ...
    Materialart: Digitale Medien
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  • 78
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 738-740 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] During a study of the effects of B. pertussis as an adjuvant in experimental allergic encephalomyelitis (EAE)7, we discovered a lethal shock-like syndrome in BALB/c mice after immunization with heat-killed B. pertussis vaccine and sensitiz-ation to bovine serum albumin (BSA). Heat-killed B. ...
    Materialart: Digitale Medien
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  • 79
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] Two mammalian and four avian cell-derived viral oncogenes encoding proteins with tyrosine-specific protein kinase activity have been described1. One of these, c-fes, is represented within the genomes of two independent isolates of feline sarcoma virus (FeSV), Gardner and Snyder-Theilen, both of ...
    Materialart: Digitale Medien
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  • 80
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] The tyrosyl tRNA synthetase (TyrTS) catalyses the aminoacylation of tRNATyr with tyrosine by a two-step mechanism in which tyrosine is first activated by ATP to form tyrosyl adenylate and then transferred to tRNATyr (refs 1,2). The nucleotide sequence of the gene has been determined from a clone in ...
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 81
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 733-734 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] Isolated endocrine cells of rat pars intermedia maintained in vitro spontaneously discharge action potentials6 which are Na spikes with a Ca component11. In such cells, GABA (2x 106 or 1 x 105 M) elicited a brief flurry of action potentials of diminishing amplitude, followed by arrest of action ...
    Materialart: Digitale Medien
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  • 82
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] Table 1 Composition of the DNA mixture used for inoculation and transfection of chimpanzee Physical state HBV DNA species HBV 14 HBV 2 HBV 6 Tandem duplications pSHH 14.3 (40 pmol) pSHH2.1 (8 pmol) Closed rings pHBV 14.1 (8 pmol) pHBV6(6 pmol) Source, physical state and amount of ...
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  • 83
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 742-744 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] Rearrangements between /H and C^ sequences were first detected among immimoglobulin-secreting hybridoma and plasmacytoma populations5'7. However, these rearrangements were largely dismissed due to the possibility that they represented tumour artefacts in these cell populations9. We therefore sought ...
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  • 84
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 752-754 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] The cross-over suppression of t haplotypes masks the true genetic nature of the region. It has previously been convenient to consider the t alleles as point mutations mapping near T. Lyon's thorough analysis of this chromosomal region using rare cross-overs established the non-allelism of several ...
    Materialart: Digitale Medien
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  • 85
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 592-596 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] We understand the structure of antibodies in detail, but know little about the molecular basis of the immunogenicity of proteins. Recent experiments have shown that chemically synthesized peptides representative of virtually any part of the surface of a protein can elicit antibodies reactive with ...
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 86
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 626-627 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] After Napoleon Bonaparte's death in May 1821, autopsy revealed an enlarged liver and a stomach lesion12. However, later neutron activation analyses of his hair4'8 have found abnormal quantities of arsenic in some (but not all) samples from his period on St Helena. Forshufvud and Weider have argued ...
    Materialart: Digitale Medien
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  • 87
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 633-635 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] Rapidly dividing fusiform cells which, in minimal media, dominate cell cultures derived from primary tissue, are generally assumed to be fibroblasts. Even though the precise origin of cells which adapt easily to culture has not been established14, they have formed the basis of most cell culture ...
    Materialart: Digitale Medien
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  • 88
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 644-645 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] The belief that Is chains were not expressed on the cell surface was based on the finding that Ij chains are only observed when metabolically labelled antigens are immunoprecipitated with anti-la antibodies and not when surf ace-iodinated material was investigated4. In an attempt to raise ...
    Materialart: Digitale Medien
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  • 89
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 625-626 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] The 160 km Fongen-Hyllingen basic complex2 (Fig. 1) is a strongly differentiated layered intrusion situated in the Trond-heim region of Norway (11.5E, 63 N). In spite of being emplaced synorogenically before the culmination of the Caledonian regional deformation and metamorphism5, it exhibits ...
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  • 90
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 638-640 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] Granulocyte-macrophage colony forming cells (GM-CFC) are haematopoietic progenitor cells which respond to GM-CSA by proliferation and differentiation in vitro10 yielding either pure or mixed colonies of granulocytes and macrophages. Sera of mice having virus-induced leukaemias contain large amounts ...
    Materialart: Digitale Medien
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  • 91
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 650-652 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] Total cellular poly(A)+ RNA was extracted from the promastigotes by phenol-SDS extraction13 and oligo(dT)-cellulose elu-tion14. RNA was translated in wheat germ15 and rabbit reticulocyte lysate16 cell-free systems and the products were compared with in vivo metabolically labelled proteins. As shown ...
    Materialart: Digitale Medien
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  • 92
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 481-481 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] Canberra The Australian Academy of Science has averted the withdrawal by the International Union of Physiological Science (IUPS) of sponsorship for the physiology congress scheduled to take place in Sydney in August-September next year. As a consequence of the Australian government's refusal to ...
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  • 93
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 484-486 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] IN the last two decades, brain catecholamines, and in particular dopamine, have played a prominent part in hypotheses of the neurobiology of schizophrenia. Briefly, the dopamine hypothesis states that in the schizophrenic brain, some critical dopamine systems are in a state of continuous ...
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  • 94
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 490-490 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] SAMPLING any fossiliferous outcrop on a centimetre-by-centimetre scale has the potential to provide detailed complete population histories over geologically short time spans (see, for example, refs 8,9). Such patterns of morphological history are, however, representative only of local populations, ...
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  • 95
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 479-479 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] Washington US universities have not done significant harm to US national security by the leakage of technical information. This is the conclusion of a report* by a panel of the US National Academy of Sciences (NAS) released last week. While agreeing with the government that the leakage of ...
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  • 96
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 481-481 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] Stockholm Last week, Sweden's new prize for science, endowed by the late Holger Crafoord, inventor of the blood dialysis machine, and his wife Anna-Greta Crafoord, was presented for the first time. The prize was awarded jointly to two mathematicians, Professor Louis Nirenberg of the Courant ...
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 97
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 482-482 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] SIR - The recent letter from C. Saccone et al. (Nature 1 July, p.8) implies that nucleic acid databases are available for European research workers only by mailing of magnetic tapes. Your readers may be interested to know that an extensive nucleic acid sequence database, including the one released ...
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 98
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 502-502 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] Journal of Molecular and Applied Genetics. Editor H.M.Goodman. 6/yr. (Raven.) $80 US, $90 elsewhere (personal); $135 US, $145 elsewhere (institutional). THE Journal of Molecular and Applied Genetics (JMAG) is designed to find a place in the library of every ...
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 99
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 502-502 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] Appetite. Chief editor D. Booth. 4/yr. (Academic.) £20.80, $54.50 (personal); £41.50, $109 (institutional). FIRST impressions of a new journal are like those of a new house: it's somehow incomplete, empty and echoing. The first issues of Appetite are certainly like that - ...
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 100
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 299 (1982), S. 504-504 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] Journal of Neuroimmunology. Editors-in-chief C.S.Raine and P.O.Behan. 6/yr in 2 vols. (Elsevier Biomedical.) Dfl. 450, $180. THE new Journal of Neuroimmunology (JN) is trying to provide a meeting point for neuropathologists and those who use immunological methods as a tool to study the ...
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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