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A detailed dinoflagellate cyst investigation of the almost continuous Middle Miocene through Pliocene of Ocean Drilling Program Hole 907A in the Iceland Sea has been conducted at 100-kyr resolution. The investigated section is well constrained by magnetostratigraphy, providing for the first time an independent temporal control on a succession of northern high-latitude dinoflagellate cyst bioevents. Based on the highest/lowest occurrences (HO/LO) and highest common occurrence (HCO) of 20 dinoflagellate cyst taxa and one acritarch species, 26 bioevents have been defined and compared with those recorded at selected DSDP, ODP, and IODP sites from the North Atlantic and contiguous seas, and in outcrops and boreholes from the onshore and offshore eastern U.S.A., and the North Sea and Mediterranean basins. Comparisons reveal near-synchronous HOs of the dinoflagellate cysts Batiacasphaera micropapillata (3.8-3.4 Ma, mid-Pliocene) and Reticulatosphaera actinocoronata (4.8-4.2 Ma, Lower Pliocene) across the Nordic Seas and North Atlantic, highlighting their value on a supraregional scale. This probably applies also to Hystrichosphaeropsis obscura (upper Tortonian), when excluding ODP Hole 907A where its sporadic upper stratigraphic range presumably relates to cooling in the early Tortonian. Over a broader time span within the upper Tortonian, the HO of Operculodinium piaseckii likely also permits correlation across the Nordic Seas and North Atlantic, and the HO of Labyrinthodinium truncatum appears useful in the Labrador and Nordic Seas. Biostratigraphic markers useful for regional rather than supraregional correlation are the HOs of Batiacasphaera hirsuta (c. 8.4 Ma, upper Tortonian) and Unipontidinium aquaeductus (c. 13.6-13.9 Ma, upper Langhian), the HCO of the acritarch Decahedrella martinheadii (c. 6.7-6.3 Ma, Messinian), and possibly the LO of Cerebrocysta irregulare sp. nov. (c. 13.8 Ma, uppermost Langhian) across the Nordic Seas. Since Habibacysta tectata, B. micropapillata, R. actinocoronata and D. martinheadii have been observed in the Arctic Ocean, they are potentially useful for high latitude correlations in the polar domain. The LOs of Habibacysta tectata and Unipontidinium aquaeductus suggest a mid- to late Langhian age (15.1-13.7 Ma) for deposits at the base of Hole 907A, thus providing new constraints on the age of basalts at the base of ODP Hole 907A. The stratigraphically important dinoflagellate cysts Cerebrocysta irregulare sp. nov., and Impagidinium elongatum sp. nov. are formally described.

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Pliocene and Pleistocene sediments from Ocean Drilling Program Leg 151, Hole 911 A, drilled on the innermost Yermak Plateau (Eastern Arctic Ocean), were studied for their dinoflagellate cyst content. Three assemblage zones were tentatively defined, characterized by the predominance of few species. The composition of the assemblages changed markedly, even within single assemblage zones, during the last 2.6 to 2.8 m.y., reflecting the variable influence of warmer water from the Norwegian Sea, fluctuations in the influence of cold polar water masses, and the extent of sea-ice cover. Polar to subpolar surface water masses prevailed on the Yermak Plateau during the late Pliocene, when the eastern Arctic Ocean was probably isolated from the Norwegian-Greenland Sea. Intrusions of warmer water are recorded since the latest Pliocene, alternating with colder periods and a prolonged seasonal sea-ice cover. The composition of the dinoflagellate cyst assemblages has also changed considerably since the middle Pleistocene, reflecting the establishment of stronger fluctuations in surface water mass conditions than before at Yermak Plateau.

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A multiproxy analysis of Hole 911A (Ocean Drilling Program (ODP) Leg 151) drilled on the Yermak Plateau (eastern Arctic Ocean) is used to investigate the behaviour of the Svalbard/Barents Sea ice sheet (SBIS) during late Pliocene and early Pleistocene (~3.0-1.7 Ma) climate changes. Contemporary with the 'Mid-Pliocene (~3 Ma) global warmth' (MPGW), a warmer period lasting ~300 kyr with seasonally ice-free conditions in the marginal eastern Arctic Ocean is assumed to be an important regional moisture source, and possibly one decisive trigger for intensification of the Northern Hemisphere glaciation in the Svalbard/Barents Sea area at ~2.7 Ma. An abrupt pulse of ice-rafted debris (IRD) to the Yermak Plateau at ~2.7 Ma reflects distinct melting of sediment-laden icebergs derived from the SBIS and may indicate the protruding advance of the ice sheet onto the outer shelf. Spectral analysis of the total organic carbon (TOC) record being predominantly of terrigenous/fossil-reworked origin indicates SBIS and possibly Scandinavian Ice Sheet response to incoming solar radiation at obliquity and precession periodicities. The strong variance in frequencies near the 41 kyr obliquity cycle between 2.7 and 1.7 Ma indicates, for the first time in the Arctic Ocean, a close relationship of SBIS growth and decay patterns to the Earth's orbital obliquity amplitudes, which dominated global ice volume variations during late Pliocene/early Pleistocene climate changes.

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DSDP 162 is located due north of DSDP 161 on the lower west flank of the East Pacific Rise about 3900 km west of the crest. It is in the Clarion-Clipperton block, about 80 km south of the Clarion Fracture Zone. The site lies at the extreme northern edge of the zone of thick sediments that parallels the equator in the Pacific and marks the region of high biological productivity.

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BACKGROUND: Bariatric surgery prevents and induces remission of type 2 diabetes in many patients. The effect of preoperative glucose status on long-term health-care costs is unknown. We aimed to assess health-care costs over 15 years for patients with obesity treated conventionally or with bariatric surgery and who had either euglycaemia, prediabetes, or type 2 diabetes before intervention. METHODS: The Swedish Obese Subjects (SOS) study is a prospective study of adults who had bariatric surgery and contemporaneously matched controls who were treated conventionally (age 37-60 years; BMI of ≥34 in men and ≥38 in women) recruited from 25 Swedish surgical departments and 480 primary health-care centres. Exclusion criteria were identical for both study groups, and were previous gastric or bariatric surgery, recent malignancy or myocardial infarction, selected psychiatric disorders, and other contraindicating disorders to bariatric surgery. Conventional treatment ranged from no treatment to lifestyle intervention and behaviour modification. In this study, we retrieved prescription drug costs for the patients in the SOS study via questionnaires and the nationwide Swedish Prescribed Drug Register. We retrieved data for inpatient and outpatient visits from the Swedish National Patient Register. We followed up the sample linked to register data for up to 15 years. We adjusted mean differences for baseline characteristics. Analyses were by intention to treat. The SOS study is registered with ClinicalTrials.gov, number NCT01479452. FINDINGS: Between Sept 1, 1987, and Jan 31, 2001, 2010 adults who had bariatric surgery and 2037 who were treated conventionally were enrolled into the SOS study. In this study, we followed up 4030 patients (2836 who were euglycaemic; 591 who had prediabetes; 603 who had diabetes). Drug costs did not differ between the surgery and conventional treatment groups in the euglycaemic subgroup (surgery US$10,511 vs conventional treatment $10,680; adjusted mean difference -$225 [95% CI -2080 to 1631]; p=0·812), but were lower in the surgery group in the prediabetes ($10,194 vs $13,186; -$3329 [-5722 to -937]; p=0·007) and diabetes ($14,346 vs $19,511; -$5487 [-7925 to -3049]; p<0·0001) subgroups than in the conventional treatment group. Compared with the conventional treatment group, we noted greater inpatient costs in the surgery group for the euglycaemic ($51,225 vs $25,313; $22,931 [19,001-26,861]; p<0·0001), prediabetes ($58,699 vs $32,861; $27,152 [18,736-35,568]; p<0·0001), and diabetes ($61,569 vs $47,569; 18,697 [9992-27,402]; p<0·0001) subgroups. We noted no differences in outpatient costs. Total health-care costs were higher in the surgery group in the euglycaemic ($71,059 vs $45,542; $22,390 [17,358-27,423]; p<0·0001) and prediabetes ($78,151 vs $54,864; $26,292 [16,738-35,845]; p<0·0001) subgroups than in the conventional treatment group, whereas we detected no difference between treatment groups in patients with diabetes ($88,572 vs $79,967; $9081 [-1419 to 19,581]; p=0·090). INTERPRETATION: Total health-care costs were higher for patients with euglycaemia or prediabetes in the surgery group than in the conventional treatment group, but we detected no difference between the surgery and conventional treatment groups for patients with diabetes. Long-term health-care cost results support prioritisation of patients with obesity and type 2 diabetes for bariatric surgery. FUNDING: AFA Försäkring and Swedish Scientific Research Council.