162,208 research outputs found
The prevalence of isolated systolic hypertension in patients 60 years of age and over attending Australian general practitioners
Howes, L G ; Reid, C ; Bendle, R ; Weaving,
[Report to Chief J. E. Curry, by an unknown author #1]
Report to Chief J. E. Curry, by an unknown author. The report contains a list of officers who gave depositions to the United States Attorney
[Report to Chief J. E. Curry, by an unknown author #2]
Report to Chief J. E. Curry, by an unknown author. The report contains a list of officers who gave depositions to the United States Attorney
Palaeoceanography of the holocene and late-glacial N.E. Atlantic: development and application of biomarker proxies of environmental change
The aim of this thesis is to develop and apply novel climate proxies to understand the palaeoceanographic evolution of the N.E. Atlantic during the late-Glacial and Holocene. The proxies investigated are based on organic molecular compounds called lipid biomarkers and bulk organic matter properties. The primary focus is on long-chain alkenones, molecules which have been extensively used in mid and low latitude open oceans to reconstruct sea surface temperatures (SSTs) during the Quaternary. Thus, the relative abundance of some alkenones is related to the growth temperature of the algae at the time of the biosynthesis of these molecules (expressed in the U(^K)(_37) and U(^K)(_37)’ indices). In high latitudes and coastal environments, the temperature dependence of alkenones is controversial, and the potential environmental information from alkenones is not yet well understood. In such locations there is increasing abundance of the C(_37:4) alkenone (quantified as %C(_37:4)). The presence of this component has been related to changes in the relative budget of freshwater in the surface ocean. A central aim of this thesis is to carry out an empirical investigation to find out the key environmental factors that control %C(_37:4) to assess its potential as a palaeoceanographic proxy. Research was conducted in the Nordic Seas and N.W. Scotland using samples from the water column, surficial sediment and sediment cores. The research undertaken can be broken down in three main sections: Alkenone distributions in the Nordic Seas. The aim was to clarify and extend the application of alkenones as palaeoceanographic proxies in subpolar to polar environments. Samples of filtered sea surface POM were analysed and extremely high %C(_37:4) values (up to 77%) were measured in polar waters (up to 80% sea-ice cover). Values of %C(_37:4) across the Nordic Seas showed a strong association with water mass type. A combined data-set revealed a stronger correlation of %C(_37:4) to sea surface salinity' (SSS, R(^2) = 0.72) than to SST (R(^2) = 0.5). However, scatter was observed in the relationship of %C(_37:4) to SSS, preventing confirmation of %C(_37:4) as a palaeo-SSS proxy. Values of %C(_37:4) in sea surface POM were high compared to surficial sediments. We discount preferential degradation of the %C(_37:4) alkenone and invoke dilution of the %C(_37:4) signal in sea surface sediments by advected allochthonous matter to explain this. The POM filter data suggest that, overall, U(^K)(_37) is a more appropriate SST index for the Nordic Seas than U(^K)(_37) '. Examination of the scatter in the U(^K)(_37) ' versus SST relationship, shows that regions in the south of the Nordic Seas (including the Icelandic shelf) may yield reliable, alkenone based, palaeoceanographic reconstructions. Comparison of %C(_37:4) distributions with dinocyst proxies in a late Holocene core from the Barents Sea suggests %C(_37:4) may be a general marker for the influence of arctic/polar water in palaeoceanographic reconstructions. The palaeoceanography of the Icelandic shelf iox. the post-Glacial period (0-15 kyr BP) was reconstructed from alkenone indices measured in three cores collected N and W of Iceland. One of the cores, JR51-GC35, contained a continuous record of Holocene sedimentation spanning 0 - 10.1 kyr BP. Superimposed on a general Holocene cooling trend in core JR5I-GC35 were millennial scale oscillations of ~2 C. The timing of the oscillations was in close agreement with the variability in IRD records from the East Greenland shelf and the timing of glacier advances in northern Iceland. A comparison of the U(^K)(_37) -SST records from JR51-GC35 and a published core from the eastern Nordic Seas (MD952011) showed significant differences (superimposed on the general trend) in the timing of millennial scale climate events. This illustrates that Holocene climate evolution in the Nordic Seas was more complex than previously suggested, with significant climatic differences between the eastern and western Nordic Seas caused by the differential variability of the Irminger and Norwegian Currents with time.The potential application for reconstructing past sea-level changes in NW. Scotland of lipid biomarkers (alkenones, n-alkanes and chlorophyll derivatives), and bulk organic parameters (%TOC, C(_nrg)/N) was assessed by a survey of modern basins (at different stages of isolation from the sea) and fossil basins (with known sea-level histories). A logit regression analysis of all the sediment samples was employed to find which of the biomarkers or bulk organic measurements could reliably characterize the sediment samples in terms of a marine/brackish or isolated/lacustrine origin. The results suggested an excellent efficiency for the alkenone index %C(_37:4) at predicting the depositional origin of the sediments. This study suggests alkenones could be used as an indicator of sea-level change in fossil isolation basins
Murder on the mountain: author talk with Peter J. Wosh
Author talk by Peter J. Wosh on May 5th, 2022, on his book, "Murder on the Mountain: crime, passion, and punishment in gilded age New Jersey.
Ice-core records of biomass burning
We review the approaches for estimating biomass burning from ice-cores and consider the challenges and assumptions in their application. In particular, we consider the potential of biomarker proxies for biomass burning, hitherto not widely applied to glacial ice archives. We also review the available records of biomass burning in ice-cores and consider how variations in fire regimes have been related to atmospheric and land-use changes. Finally, we suggest that future developments in ice-core science should aim to combine multiple biomarkers with other records (black carbon, charcoal) and models to discern the types of material being burnt (C3 versus C4 plants, angiosperms, gymnosperms, peat fires, etc.) and to improve constraints on source areas of biomass burning. An ultimate goal is to compare the biomass burning record from ice-cores with hindcasts from models to project how future climate change will influence biomass burning and, inversely, how fire will affect climate
Mr. Melvin J. Collier, RWWL AUC, June 2011
This video is a conversation with Mr. Melvin J. Collier. Mr. Collier talks about his book, "From Mississippi to Africa: A Journey of Discovery". Daniel Le, AUC Woodruff Library, is the interviewer
Oceanic forcing of the Marine Isotope Stage 11 interglacial
The interglacial known as Marine Isotope Stage 11 has been proposed to be analogous to the Holocene, owing to similarities in the amplitudes of orbital forcing. It has been difficult to compare the periods, however, because of the long duration of Stage 11 and a lack of detailed knowledge of any extreme climate events that may have occurred. Here we use the distinctive phasing between seasurface temperatures and the oxygen-isotope records of benthic foraminifera in the southeast Atlantic Ocean to stratigraphically align the Holocene interglacial with the first half of the Marine Isotope Stage 11 interglacial optimum. This alignment suggests that the second half of Marine Isotope Stage 11 should not be used as a reference for 'pre-anthropogenic' greenhouse-gas emissions. By compiling benthic carbon-isotope records from sites in the Atlantic Ocean on a single timescale, we also find that meridional overturning circulation strengthened about 415,000 years ago, at a time of high orbital obliquity. We propose that this mechanism transported heat to the high northern latitudes, inhibiting significant ice-sheet build-up and prolonging interglacial conditions. We suggest that this mechanism may have also prolonged other interglacial periods throughout the past 800,000 years
A Tripartite Post-Recession Rebalancing
In this latest Advance & Rutgers Report, entitled “A Tripartite Post-Recession Rebalancing,” Dean James W. Hughes and Professor Joseph J. Seneca deliver an incisive assessment of the current market conditions and obstacles in the path of our economic recovery. They offer a statistical cautionary tale that the private and public sector need to hear and acknowledge in order for the economy to make continued progress.This report was published as Issue Paper Number 7, November 2011, in Advance & Rutgers Report
Evidence for the decay B0→J/ψω and measurement of the relative branching fractions of meson decays to J/ψη and J/ψη′
First evidence of the B 0 → J / ψ ω decay is found and the B s 0 → J / ψ η and B s 0 → J / ψ η ′ decays are studied using a dataset corresponding to an integrated luminosity of 1.0 fb -1 collected by the LHCb experiment in proton-proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV. The branching fractions of these decays are measured relative to that of the B 0 → J / ψ ρ 0 decay:frac(B (B 0 → J / ψ ω), B (B 0 → J / ψ ρ 0)) = 0.89 ± 0.19 (stat) - 0.13 + 0.07 (syst),frac(B (B s 0 → J / ψ η), B (B 0 → J / ψ ρ 0)) = 14.0 ± 1.2 (stat) - 1.5 + 1.1 (syst) - 1.0 + 1.1 (frac(f d, f s)),frac(B (B s 0 → J / ψ η ′), B (B 0 → J / ψ ρ 0)) = 12.7 ± 1.1 (stat) - 1.3 + 0.5 (syst) - 0.9 + 1.0 (frac(f d, f s)), where the last uncertainty is due to the knowledge of f d / f s, the ratio of b-quark hadronization factors that accounts for the different production rate of B 0 and B s 0 mesons. The ratio of the branching fractions of B s 0 → J / ψ η ′ and B s 0 → J / ψ η decays is measured to befrac(B (B s 0 → J / ψ η ′), B (B s 0 → J / ψ η)) = 0.90 ± 0.09 (stat) - 0.02 + 0.06 (syst)
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