To simulate the effects of burnable poison doping in nuclear fuel UO2,Er2O3(or Gd2O3)-doped CeO2 pellets were prepared. Changes in lattice constant and atomic disordering for CeO2 due to the Er2O3 and Gd2O3 doping wer...
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To simulate the effects of burnable poison doping in nuclear fuel UO2,Er2O3(or Gd2O3)-doped CeO2 pellets were prepared. Changes in lattice constant and atomic disordering for CeO2 due to the Er2O3 and Gd2O3 doping were measured by means of XRD and XAFS. By the Er2O3 doping,the lattice constant decreased,and a disordering of lattice structure was induced in the samples. The doping with Er2O3 also induced the disordering of atomic arrangement around Er atoms,which was observed through the change in XAFS spectra. In contrast,the effect of Gd2O3 doping was smaller than that of Er2O3 doping. The result was discussed in terms of ionic size of dopants in CeO2 crystal.
AIM: To examine the long term survival of geriatric patients treated with percutaneous endoscopic gastrostomy (PEG) in Japan. METHODS: We retrospectively included 46 Japanese community and tertiary hospitals to invest...
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AIM: To examine the long term survival of geriatric patients treated with percutaneous endoscopic gastrostomy (PEG) in Japan. METHODS: We retrospectively included 46 Japanese community and tertiary hospitals to investigate 931 consecutive geriatric patients (≥ 65 years old) with swallowing difficulty and newly performed PEG between Jan 1st 2005 and Dec 31st 2008. We set death as an outcome and explored the associations among patient’s characteristics at PEG using log-rank tests and Cox proportional hazard models. RESULTS: Nine hundred and thirty one patients were followed up for a median of 468 d. A total of 502 deaths were observed (mortality 53%). However, 99%, 95%, 88%, 75% and 66% of 931 patients survived more than 7, 30, 60 d, a half year and one year, respectively. In addition, 50% and 25% of the patients survived 753 and 1647 d, respectively. Eight deaths were considered as PEG-related, and were associated with lower serum albumin levels (P = 0.002). On the other hand, among 28 surviving patients (6.5%), PEG was removed. In a multivariate hazard model, older age [hazard ratio (HR), 1.02; 95% confidence interval (CI), 1.00-1.03; P = 0.009], higher C-reactive protein (HR, 1.04; 95% CI: 1.01-1.07; P = 0.005), and higher blood urea nitrogen (HR, 1.01; 95% CI: 1.00-1.02; P = 0.003) were significant poor prognostic factors, whereas higher albumin (HR, 0.67; 95% CI: 0.52-0.85; P = 0.001), female gender (HR, 0.60; 95% CI: 0.48-0.75; P < 0.001) and no previous history of ischemic heart disease (HR, 0.69; 95% CI: 0.54-0.88, P = 0.003) were markedly better prognostic factors. CONCLUSION: These results suggest that more than half of geriatric patients with PEG may survive longer than 2 years. The analysis elucidated prognostic factors.
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