New Insights on the Sequence Stratigraphic Architecture of the Dakota Formation in Kansas–Nebraska–Iowa from a Decade of Sponsored Research Activity

The Cretaceous Dakota Formation in the areas of Kansas, Nebraska, and Iowa contains a rich and well-preserved microflora of fossil palynomorphs. A comprehensive listing of these taxa is presented in this publication as part of a continuing effort to develop a refined biostratigraphic scheme for mid-Cretaceous terrestrial deposits in North America. The Dakota Formation in this region contains four distinctive Albian-Cenomanian palynostratigraphic zones that are used to partition the unit into successive depositional cycles, and each zone records deposition in fluvial-estuarine environments. The late Albian Kiowa-Skull Creek depositional cycle at the base of the Dakota Formation is recognized throughout the study area, and is also recognized in other parts of the Cretaceous North American Western Interior basin. The overlying newly recognized latest Albian "Muddy-Mowry Cycle" is formally defined for the first time in this paper and correlates with depositional cycles recognized by other workers in other parts of the Western Interior basin. The Cenomanian lower Greenhorn Cycle is already widely recognized by many other workers throughout the Western Interior basin. Laterally extensive thin zones of pervasive carbonate mineral cementation are noted in fluvial-estuarine deposits in the Dakota Formation. They are believed to have formed as synsedimentary cements that precipitated below estuarine marine-flooding surfaces in settings related to discharging paleoground waters. The existence of these early diagenetic cementation zones has important implications for the recognition of diagenetic barriers and baffles to modern fluid flow in the Dakota Formation. New stable isotopic data on these authigenic cements are reported in this paper and add to a body of published data on the δ18O of mid-Cretaceous paleoprecipitation in North America

Pharmacokinetic-Pharmacodynamic Modelling of the Analgesic and Antihyperalgesic Effects of Morphine after Intravenous Infusion in Human Volunteers

Using a modelling approach, this study aimed to (i) examine whether the pharmacodynamics of the analgesic and antihyperalgesic effects of morphine differ; (ii) investigate the influence of demographic, pain sensitivity and genetic (OPRM1) variables on between-subject variability of morphine pharmacokinetics and pharmacodynamics in human experimental pain models. The study was a randomized, double-blind, 5-arm, cross-over, placebo-controlled study. The psychophysical cutaneous pain tests, electrical pain tolerance (EPTo) and secondary hyperalgesia areas (2HA) were studied in 28 healthy individuals (15 males). The subjects were chosen based on a previous trial where 100 subjects rated (VAS) their pain during a heat injury (47°C, 7 min., 12.5 cm²). The 33% lowest- and highest pain-sensitive subjects were offered participation in the present study. A two-compartment linear model with allometric scaling for weight provided the best description of the plasma concentration-time profile of morphine. Changes in the EPTo and 2HA responses with time during the placebo treatment were best described by a linear model and a quadratic model, respectively. The model discrimination process showed clear evidence for adding between-occasion variability (BOV) on baseline and the placebo slope for EPTo and 2HA, respectively. The sensitivity covariate was significant on baseline EPTo values and genetics as a covariate on the placebo slope for 2HA. The analgesic and antihyperalgesic effects of morphine were pharmacologically distinct as the models had different effect site equilibration half-lives and different covariate effects. Morphine had negligible effect on 2HA, but significant effect on EPTo.Pernille Ravn, David J.R. Foster, Mads Kreilgaard, Lona Christrup, Mads U. Werner, Erik L. Secher, Ulrik Skram and Richard Upto

New measurement of exotic decay of 225^{225}Ac by 14^{14}C emission

The branching ratio of $^{225}$Ac decay by emission of $^{14}$C was remeasured under improved experimental conditions by using a radioactive source produced at the ISOLDE mass-separator at CERN and a nuclear track detector technique. The result, B=$\lambda_{^{14}\textrm{C}} / \lambda_{\alpha} = (4.5 \pm 1.4) 10^{-12}$, is consistent with the anomalously high value obtained in the 1993 experiment thus confirming the importance of nuclear structure effects in this exotic decay

Effects of thermal shocks on the release of radioisotopes and on molten metal target vessels

The ISOLDE pulsed proton beam peak power amounts to 500 MW during the 2.4 ms proton pulse. The fraction of the proton pulse energy deposited in the target material is at the origin of severe thermal shocks. Quantitative measurement of their effect on the release of radioelements from ISOLDE targets was obtained by comparison of release profiles measured under different proton beam settings. The thermal shock induced in liquids (Pb, Sn, La) lead to mechanical failure of ISOLDE molten metal target vessels. Failure analysis is presented and discussed in the light of the response of mercury samples submitted to the ISOLDE beam and monitored by high-speed optical systems

The acceleration and storage of radioactive ions for a neutrino factory

The term beta-beam has been coined for the production of a pure beam of electron neutrinos or their antiparticles through the decay of radioactive ions circulating in a storage ring. This concept requires radioactive ions to be accelerated to a Lorentz gamma of 150 for 6He and 60 for 18Ne. The neutrino source itself consists of a storage ring for this energy range, with long straight sections in line with the experiment(s). Such a decay ring does not exist at CERN today, nor does a high-intensity proton source for the production of the radioactive ions. Nevertheless, the existing CERN accelerator infrastructure could be used as this would still represent an important saving for a beta-beam facility. This paper outlines the first study, while some of the more speculative ideas will need further investigations.Comment: Accepted for publication in proceedings of Nufact02, London, 200

The evolution of the ISOLDE control system

The ISOLDE on-line mass separator facility is operating on a Personal Computer based control system since spring 1992. Front End Computers accessing the hardware are controlled from consoles running Microsoft WindowsTM through a Novell NetWare4TM local area network. The control system is transparently integrated in the CERN wide office network and makes heavy use of the CERN standard office application programs to control and to document the running of the ISOLDE isotope separators. This paper recalls the architecture of the control system, shows its recent developments and gives some examples of its graphical user interface