1,540 research outputs found
Alkali oxide-tantalum, niobium and antimony oxide ionic conductors
The phase equilibrium relations of four systems were investigated in detail. These consisted of sodium and potassium antimonates with antimony oxide and tantalum and niobium oxide with rubidium oxide as far as the ratio 4Rb2O:llB2O5 (B=Nb, Ta). The ternary system NaSbO3-Sb2O4-NaF was investigated extensively to determine the actual composition of the body centered cubic sodium antimonate. Various other binary and ternary oxide systems involving alkali oxides were examined in lesser detail. The phases synthesized were screened by ion exchange methods to determine mobility of the mobility of the alkali ion within the niobium, tantalum or antimony oxide (fluoride) structural framework. Five structure types warranted further investigation; these structure types are (1) hexagonal tungsten bronze (HTB), (2) pyrochlore, (3) the hybrid HTB-pyrochlore hexagonal ordered phases, (4) body centered cubic antimonates and (5) 2K2O:3Nb2O5. Although all of these phases exhibit good ion exchange properties only the pyrochlore was prepared with Na(+) ions as an equilibrium phase and as a low porosity ceramic. Sb(+3) in the channel interferes with ionic conductivity in this case, although relatively good ionic conductivity was found for the metastable Na(+) ion exchanged analogs of RbTa2O5F and KTaWO6 pyrochlore phases
Kentucky Probationers\u27 and Parolees\u27 Perceptions of the Severity of Prison versus County Jail and Probation
This study extends a growing body of research on offenders\u27 perceptions of the punitiveness of criminal sanctions. Specifically, we examine punishment equivalency ratings by Kentucky probationers and parolees (N-588) meant to gauge their perceptions of the severity of prison compared to both probation and county jail. Ratings are analyzed by several demographic characteristics. We find that, in general, survey respondents pereceived county jail as more severe than prison but that probation was rated as less severe
Robust velocity dispersion and binary population modeling of the ultra-faint dwarf galaxy Reticulum II
We apply a Bayesian method to model multi-epoch radial velocity measurements
in the ultra-faint dwarf galaxy Reticulum II, fully accounting for the effects
of binary orbital motion and systematic offsets between different spectroscopic
datasets. We find that the binary fraction of Ret II is higher than 0.5 at the
90% confidence level, if the mean orbital period is assumed to be 30 years or
longer. Despite this high binary fraction, we infer a best-fit intrinsic
dispersion of 2.8 km/s, which is smaller than previous
estimates, but still indicates Ret II is a dark-matter dominated galaxy. We
likewise infer a 1% probability that Ret II's dispersion is due to
binaries rather than dark matter, corresponding to the regime
2. Our inference of a high close binary fraction
in Ret II echoes previous results for the Segue 1 ultra-faint dwarf and is
consistent with studies of Milky Way halo stars that indicate a high close
binary fraction tends to exist in metal-poor environments.Comment: 9 pages, 5 figures, to be submitted to MNRA
Oxygen persufflation as adjunct in liver preservation (OPAL): Study protocol for a randomized controlled trial
<p>Abstract</p> <p>Background</p> <p>Early graft dysfunction due to preservation/reperfusion injury represents a dramatic event after liver transplantation. Enhancement of donor organ criteria, in order to cope with the ever increasing donor shortage, further increases graft susceptibility to ischemic alterations.</p> <p>Major parts of post-preservation injury, however, occur at the time of warm reperfusion but not during ischemic storage; successful reperfusion of ischemic tissue in turn depends on an adequate redox and intracellular signal homeostasis. The latter has been shown experimentally to be favorably influenced by oxygen persufflation within short time spans. Thus viability of marginally preserved liver grafts could still be augmented by transient hypothermic reconditioning <b><it>even after </it></b>normal procurement and static cold storage. The present study is aimed to confirm the conceptual expectations, that hypothermic reconditioning by gaseous oxygen persufflation is a useful method to suppress injurious cellular activation cascades and to improve post-ischemic recovery of marginally preserved liver grafts.</p> <p>Methods/Design</p> <p>OPAL is a prospective single center randomized proof of concept study, including two parallel groups in a total of 116 liver transplant patients. The effect of an in hospital treatment of the isolated liver graft by 2 hours of oxygen persufflation immediately prior to transplantation will be assesses as compared to standard procedure (cold storage without further intervention). The primary endpoint is the peak transaminase serum level (AST) during the first three days after transplantation as a surrogate readout for parenchymal liver injury. Other outcomes comprise patient and graft survival, time of intensive care requirement, hepatic tissue perfusion 1h after revascularisation, early onset of graft dysfunction based on coagulation parameters, as well as the use of a refined scoring-system for initial graft function based on a multi-parameter (AST, ALT, Quick and bilirubin) score. Furthermore, the effect of OPAL on molecular pathways of autophagy and inflammatory cell activation will be evaluated. Final analysis will be based on all participants as randomized (intention to treat).</p> <p>Trial Registration</p> <p>Current Controlled Trials <a href="http://www.controlled-trials.com/ISRCTN00167887">ISRCTN00167887</a></p
Corn, 1992
Harry C. Minor is an Associate Professor of Agronomy and State Extension Specialist, Carl G. Morris and Howard L. Mason are Senior Research Specialists, and Delbert R. Knerr, David B. Thomas and C. Stephen Lankheit are Research Specialists in Agronomy.Compares hybrids and includes experimental procedures, yield results and seed corn company addresses.Comparing hybrids -- Experimental procedures -- Summary of results -- Yield results -- Seed corn company addresse
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