Integrated Ocean Drilling Program Expedition 317/319 Scientific Prospectus: Pacific Equatorial Age Transect

As the world's largest ocean, the Pacific is intricately linked to major changes in the global climate system. Throughout the Cenozoic, Pacific plate motion has had a northward component. Thus, the Pacific is unique in that the thick sediment bulge of biogenic-rich deposits from the currently narrowly focused zone of equatorial upwelling is slowly moving away from the Equator. Hence, older sections are not deeply buried and can be recovered by drilling. Previous drilling in this area during Ocean Drilling Program (ODP) Legs 138 and 199 was remarkably successful in giving us new insights into the workings of the climate and carbon system, productivity changes across the zone of divergence, time-dependent calcium carbonate dissolution, bio- and magnetostratigraphy, the location of the Intertropical Convergence Zone (ITCZ), and evolutionary patterns for times of climatic change and upheaval. Together with older Deep Sea Drilling Project drilling in the eastern equatorial Pacific, both legs also helped to delineate the position of the paleoequator and variations in sediment thickness from ~150°W to 110°W.The Pacific equatorial age transect (PEAT) science program is based on Integrated Ocean Drilling Program (IODP) Proposal 626 and consists of Expeditions 317 and 319, grouped into one science program. The goal is to recover a continuous Cenozoic record of the equatorial Pacific by drilling at the paleoposition of the Equator at successive crustal ages on the Pacific plate. Records collected from Expeditions 317 and 319 are to be joined with records of previous drilling during ODP Legs 138 and 199 to make a complete equatorial Pacific record from 0 to 55 Ma. Previously, ODP Legs 138 and 199 were designed as transects across the paleoequator in order to study the changing patterns of sediment deposition across equatorial regions at critical time intervals. As we have gained more information about the past movement of plates and when in Earth's history "critical" climate events took place, it becomes possible to drill an age transect ("flow-line") along the position of the Pacific paleoequator. The goal of this transect is to target important time slices where calcareous sediments have been best preserved and the sedimentary archive will allow us to reconstruct past climatic and tectonic conditions. Leg 199 enhanced our understanding of extreme changes of the calcium carbonate compensation depth (CCD) across major geological boundaries during the last 55 m.y. A very shallow CCD during most of the Paleogene makes it difficult to obtain well-preserved sediments during these stratigraphic intervals, but the strategy of site locations for the current two expeditions is designed to occupy the most promising sites and to obtain a unique sedimentary biogenic sediment archive for time periods just after the Paleocene/Eocene boundary event, Eocene cooling, the Eocene–Oligocene transition, the "one cold pole" Oligocene, the Oligocene–Miocene transition, and the Miocene. These new cores and data will significantly contribute to the objectives of the IODP Extreme Climates Initiative and will provide material that the previous legs were not able to recover.For logistical reasons, the PEAT science program is composed of two expeditions but is being implemented as a single science program to best achieve the overall objectives of Proposal 626. Participants on both expeditions (as well as approved shore-based scientists) will comprise a single science party with equal access to data and materials from both cruises. Sampling aboard the ship will be minimal, and the bulk of the sampling will be completed postcruise.The operational plan is to occupy eight sites along the age transect with the goal of recovering as complete a sedimentary succession as possible. This will probably require three holes to be cored at each site with wireline logging operations in one hole. Basement will be tagged in at least one of the holes. Expedition 317 will be directed primarily to sample the Neogene sites (proposed Sites PEAT-2C, 6C, and 7C, in priority order). The second expedition (319) will primarily sample the Paleogene sites (proposed Sites PEAT-1C, 3C, 4C, and possibly 5C, in priority order)

IODP Proposal 626: "Cenozoic Equatorial Age Transect – Following the Palaeo-equator"

As the largest ocean, the Pacific is intricately linked to major changes in the global climate system that took place during the Cenozoic. Throughout the Cenozoic the Pacific plate has had a northward component. Thus, the Pacific is unique, in that the thick sediment bulge of biogenic rich deposits from the currently narrowly focused zone of equatorial upwelling is slowly moving away from the equator. Hence, older sections are not deeply buried and can be recovered by drilling. Previous ODP Legs 138 and 199 were designed as transects across the paleo-equator in order to study the changing patterns of sediment deposition across equatorial regions, while this proposal aims to recover an orthogonal “age-transect” along the paleo-equator. Both previous legs were remarkably successful in giving us new insights into the workings of the climate and carbon system, productivity changes across the zone of divergence, time dependent calcium carbonate dissolution, bio- and magnetostratigraphy, the location of the ITCZ, and evolutionary patterns for times of climatic change and upheaval. Together with older DSDP drilling in the eastern equatorial Pacific, both Legs also helped to delineate the position of the paleo-equator and variations in sediment thickness from approximately 150°W to 110°W. As we have gained more information about the past movement of plates, and where in time “critical” climate events are located, we now propose to drill an age-transect (“flow-line”) along the position of the paleo-equator in the Pacific, targeting selected time-slices of interest where calcareous sediments have been preserved best. Leg 199 enhanced our understanding of extreme changes of the calcium carbonate compensation depth across major geological boundaries during the last 55 million years. A very shallow CCD during most of the Paleogene makes it difficult to obtain well preserved sediments, but we believe our siting strategy will allow us to drill the most promising sites and to obtain a unique sedimentary biogenic carbonate archive for time periods just after the Paleocene- Eocene boundary event, the Eocene cooling, the Eocene/Oligocene transition, the “one cold pole” Oligocene, the Oligocene-Miocene transition, and the Miocene, contributing to the objectives of the IODP Extreme Climates Initiative, and providing material that the previous legs were not able to recover

Use of Repeated Blood Pressure and Cholesterol Measurements to Improve Cardiovascular Disease Risk Prediction: An Individual-Participant-Data Meta-Analysis

The added value of incorporating information from repeated blood pressure and cholesterol measurements to predict cardiovascular disease (CVD) risk has not been rigorously assessed. We used data on 191,445 adults from the Emerging Risk Factors Collaboration (38 cohorts from 17 countries with data encompassing 1962-2014) with more than 1 million measurements of systolic blood pressure, total cholesterol, and high-density lipoprotein cholesterol. Over a median 12 years of follow-up, 21,170 CVD events occurred. Risk prediction models using cumulative mean values of repeated measurements and summary measures from longitudinal modeling of the repeated measurements were compared with models using measurements from a single time point. Risk discrimination (Cindex) and net reclassification were calculated, and changes in C-indices were meta-analyzed across studies. Compared with the single-time-point model, the cumulative means and longitudinal models increased the C-index by 0.0040 (95% confidence interval (CI): 0.0023, 0.0057) and 0.0023 (95% CI: 0.0005, 0.0042), respectively. Reclassification was also improved in both models; compared with the single-time-point model, overall net reclassification improvements were 0.0369 (95% CI: 0.0303, 0.0436) for the cumulative-means model and 0.0177 (95% CI: 0.0110, 0.0243) for the longitudinal model. In conclusion, incorporating repeated measurements of blood pressure and cholesterol into CVD risk prediction models slightly improves risk prediction

The status of Arctic charr Salvelinus alpinus in Britain and Ireland

The Arctic charr occurs in lakes across Britain and Ireland and was previously described here as 15 separate species. Most authorities now agree that all these stocks belong to a single polymorphic species complex Salvelinus alpinus (L.). This fish is given little protection in British and Irish law and there has been a steady loss of natural populations in recent years in all the countries concerned. A few new stocks have been created either intentionally or accidentally. In Scotland, only a small proportion of the 258 recorded natural populations has been studied and at least 12 of these are now extinct. There are at least four introduced populations originating from native Scottish stocks, but the fate of stocks introduced from Canada for aquaculture is uncertain. In England, there are eight extant populations in Cumbria and four others extinct. The status of introduced stocks in England is uncertain but there is probably one population surviving in Yorkshire. In Wales, eight lakes with resident Arctic charr populations have been recorded, three of these populations are natural, one is extinct and four have been introduced. In Ireland, of the 74 known populations, approximately 30% are extinct. There is no evidence to indicate that introduced stocks (some of them from Iceland) in a small number of lakes have survived there. A range of factors is involved in the extinction of populations and these include pollution, eutrophication, acidification, afforestation, engineering, exploitation, aquaculture, introductions and climate change. Much research remains to be done and unique stocks of this valuable species will continue to be lost unless positive action is taken through local conservation management backed by appropriate national legislation