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Recent progress of the NEDO project on durability/reliability of SOFC stacks is reported with an emphasis on the achievement of Mitsubishi Heavy Industries' segment-in-series cells in which the lanthanum manganite cathode has been improved. Durability tests were made by CRIEPI on their cells with/without doped ceria interlayer to check plausible effects of microstructure change and of chromium poisoning. Improved cells exhibit essentially no degradation for 10,000 h and also strong tolerance against the Cr contamination from stainless steel tubes. These features are discussed within the generalized degradation model developed inside the NEDO project. In particular, the extremely small overpotential can be considered to be effective in lowering the Cr poisoning by reducing the driving forces for the electrochemical Cr deposition at active sites. Insertion of doped ceria is also useful in preventing the Cr deposition or enhancing the volatilization of deposited Cr with cathodically emitted water vapors from ceria. Thermodynamic considerations reveal that the initial composition of LSM cathode is important to determine the microstructure change due to the chromium dissolution into the B-sites in the perovskite lattice. Discussions are made on a role of doped ceria to prevent deterioration of Mn-dissolved electrolyte by lowering the Mn dissolution into YSZ. [ABSTRACT FROM AUTHOR]

In this observational cohort study, the authors assessed the achievement of treatment goals as defined in the Japanese Society of Hypertension's Guidelines for the Management of Hypertension (JSH 2004) among 2743 Japanese hypertensive patients who were followed for 1 year (follow-up rate of 82.6%). Median age was 72 years, and 45% were men. Achievement of treatment goals across all 4 seasons was very low, at 4.1% among patients with diabetes mellitus or renal disease, 3.9% among nonelderly patients (<65 years of age) without these diseases, and 30.8% among elderly patients (>or=65 years of age) without these diseases. These findings highlight the importance of maintaining appropriate blood pressure control. In addition, an analysis of factors associated with achievement rates identified the importance of weight control, lifestyle modification, and family history, and indicated a need for better blood pressure management before complications arise. [ABSTRACT FROM AUTHOR]

The objective of this study was to assess the extent of diabetic control and its associated factors among Vietnamese patients with diabetes mellitus (DM). The study was conducted among 652 outpatients who were recruited at a public general hospital (People Hospital 115) and a private clinic (Medic Center) in Ho Chi Minh City, Vietnam. Median age of participants was 57 years from People Hospital 115, and 60 years for participants from Medic Center. Thirty-nine percent of patients at People Hospital 115 and 33% of patients at Medic Center had Hemoglobin A1c (HbA1c) greater than 8%. However, 55% and 45% of these patients from each facility reported they are in good control. There was a high percentage of missing data regarding possible complications at both sites. It was also observed a high proportion of patients with a discrepancy between perception and actual control of diabetic condition. Many of these patients showed less distress and had a high self-rating regarding their adherence to a lifestyle regimen. Furthermore, some of these patients were smokers and had a history of atherosclerotic disease. Overall, Vietnamese diabetic patients in this study exhibited poor plasma glucose control. Physician education designed to improve monitoring of glucose levels and diabetic complications, and patient education aimed at raising awareness about actual diabetic control are indicated in this population. [ABSTRACT FROM AUTHOR]

This observational study assessed the achievement of treatment goals, as defined by the Japanese Society of Hypertension Guidelines for the Management of Hypertension (JSH 2004). These goals are: <140/80 mm Hg in elderly patients (65 years and older), <130/80 mm Hg in patients with diabetes or kidney disease, and <130/85 mm Hg in younger patients (younger than 65). From July 2006 to May 2007, 72 physician members of the Fukushima Hypertension Conference enrolled a total of 3320 patients from Fukushima Prefecture, Japan. The median age of the patients was 71 years and 46% were male. The success rate was 27% among patients with diabetes mellitus or renal disease, 30% among those younger than 65 years, and 66% among the elderly without the diseases. Factors significantly associated with an increased risk of failure to achieve goals were obesity, dyslipidemia, family histories of diabetes mellitus or hypertension, and number of antihypertensive drugs used. The presence of atherosclerotic complications decreased the risk. This study revealed low achievement rates, identified the importance of weight control and family histories, and indicated a need for better management to prevent complications. [ABSTRACT FROM AUTHOR]

The exergetic and thermal efficiency of hybrid systems using various solid oxide fuel cell (SOFC) intermediate-temperature fuel cell electrolytes at various temperatures and electrolyte thicknesses was simulated and evaluated. Electrolytes reported on here include lanthanum strontium gallate magnesite, yttria-stabilized zirconium, and gadolinium-doped ceria oxide (GDC). The Wagner mass transfer model (MTM), which includes solid-state oxygen-ion, hole, and electron conduction, was incorporated into a thermodynamic model for a simple hybrid system. The MTM-projected performance trends for the various electrolytes agreed well with trends previously observed experimentally by the authors for electrolytes alone. The projected exergetic performance with the typical thermodynamic model without the incorporation of the MTM generally gave higher performance over a broader temperature range than expected through experimental trends previously observed. Thus, the projected performance of these very important hybrid systems can be greatly impacted by electrolyte choice and electronic conductivity. GDC was predicted to have a good exergetic efficiency, but only over a very narrow temperature region. A thermodynamically consistent picture of SOFC exergetic performance from the defect chemistry and solid-state electrochemistry to the phenomenological fuel cell and macroscopic thermodynamic performance was established. [ABSTRACT FROM AUTHOR]

The preferential site for oxygen isotope exchange was investigated on layered films of La2-xSrxCoO4 (x = 0.5,1.0)/La0.6Sr0.4CoO3 prepared by pulsed laser deposition (PLD) on a polycrystalline Ce0.9Gd0.1O1.95. An isotope exchange experiment was performed at 773 K in 18O-enriched oxygen of 0.2 × 105 Pa. Three-dimensional imaging of secondary ion mass spectrometry (SIMS) was carried Out to visualize the isotope distribution. The SIMS images suggested that there are fast oxygen-incorporation paths along the hetero-phase interface of La2-xSrxCoO4/La0.6sSr0.4CoO3. The results have reproduced our former findings on the fast oxygen surface exchange with La2-xSr.xCoO4/La0.6Sr0.4CoO3 composite polycrystals. [ABSTRACT FROM AUTHOR]

Nanocrystalline La1− x Sr x CoO3−δ (LSC) thin films with a nominal Sr content x = 0.5 were deposited on 3.5 mol% yttria-stabilized zirconia (YSZ) substrates by a low-temperature sol–gel process followed by a rapid thermal annealing procedure at temperatures up to 900 °C. The structural and chemical stability of the as-prepared nanocrystalline LSC and demixing effects within the thin film or at the LSC/YSZ interface were studied after long-time exposure at temperatures between 700 °C and 1,000 °C. The grain size and surface topography were analyzed by scanning electron microscopy. Transmission electron microscopy combined with selected-area electron diffraction, energy-dispersive X-ray spectrometry, and electron-spectroscopic imaging was applied for the investigation of the microstructure and the analysis of the local chemical composition and element distribution on the nanoscale. Chemical potential calculations, which were performed to assess the decomposition of LSC/YSZ as a function of temperature, show good agreement with the experimental results. [ABSTRACT FROM AUTHOR]

The effect of the electrode material on the high voltage stoichiometry-polarization (“electrocoloration”) of Fe-doped SrTiO3 single crystals has been studied. For different electrode materials (150-nm Ag/15-nm Cr and 150-nm Au/15-nm Cr) secondary ion mass spectrometry (SIMS) was used to measure the depth profile of the 18O-isotope after high-field stress. The results were compared with spatially resolved impedance measurements on electrocolored Fe-doped SrTiO3 single crystals. For Au/Cr as well as Ag/Cr electrodes a large dc voltage leads to moving color fronts which are usually correlated with a pronounced stoichiometry polarization of the samples due to electrodes blocking the ionic current. However, the local impedance measurements demonstrate that the conductivity profiles near the cathode depend on the electrode material. This finding is in accordance with the SIMS measurements which indicate that the Ag/Cr-electrodes are, in contrast to Au/Cr-electrodes not completely inactive for the oxygen incorporation into the Fe-doped SrTiO3. The results are discussed in terms of defect chemical models. [ABSTRACT FROM AUTHOR]

Abstract The A-to-G mutation at nucleotide 3243 of the mitochondrial tRNA[sup Leu(UUR)] gene (mt.3243A>G) is associated with both diabetes mellitus and myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS). Recently, this mutation was found in three diabetic subjects with progressive kidney disease, suggesting that it may be a contributing factor in the development of kidney disease in patients with diabetes. The aim of this study was to evaluate the contribution of this mutation to the development of end stage renal disease (ESRD) in patients with diabetes. The study group consisted of 135 patients with diabetes and ESRD. The control group consisted of 92 non-diabetic subjects with ESRD who were receiving hemodialysis. The mt.3243A>G mutation was detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). We found the mt.3243A>G mutation in eight patients (8/135; 5.9%), all of whom were initially diagnosed with type II diabetes. Five of the eight patients were subsequently also diagnosed with MELAS. We did not find the mutation in any of the 92 nondiabetic subjects with ESRD. The prevalence of this mutation was 6.5-fold higher in patients with diabetes and ESRD than in those with diabetes alone (8/135 vs 5/550, respectively; chi[sup 2] = 13.704; P = 0.0002). The mt.3243A>G mutation may be a contributing genetic factor in the development of ESRD in Japanese patients with diabetes. [ABSTRACT FROM AUTHOR]