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51.
Na2Ti6O13 (NTO) has recently been reported for lithium ion storage and showed very promising results. In this work, we report substantially enhanced rate capability in NTO nanowires by Ti(iii) self-doping and carbon-coating. Ti(iii) doping and carbon coating were found to work in synergy to increase the electrochemical performances of the material. For 300 cycles at 1C (1C = 200 mA g−1) the charge capacity of the electrode is 206 mA h g−1, much higher than that (89 mA h g−1) of the pristine NTO electrode. For 500 cycles at 5C the electrode can still deliver a charge capacity of 180.5 mA h g−1 with a high coulombic efficiency of 99%. At 20C the capacity of the electrode is 2.6 times that of the pristine NTO. These results clearly demonstrate that the Ti(iii) self-doping and uniform carbon coating significantly enhanced the kinetic processes in the NTO nanowire crystal, making it possible for fast charge and discharge in Li-ion batteries.

Ti3+ self-doping and carbon-coating are efficient approaches to simultaneously improve the rate capability and cyclability of Na2Ti6O13 nanowires for lithium storage.  相似文献   
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OBJECTIVE: To describe the incidence, cause, and course of anaemia in rheumatoid arthritis (RA). METHODS: Medical records of 225 patients who received a diagnosis of RA between 1990 and 1992 were reviewed longitudinally for mention of anaemia. Anaemia was classified as anaemia of chronic disease if ferritin concentrations reflected adequate body iron stores. Among iron depleted anaemic patients, iron deficiency anaemia was identified using the response to iron supplementation. RESULTS: Anaemia developed in 64% of the patients, mostly within 18 months of follow up, but disappeared again in 54% of those patients. The prevalence of anaemia varied from 39% to 53% throughout follow up. Iron depletion was found in 38% of anaemic patients; 40% of them did not recover from their anaemia after iron supplementation and were classified as having anaemia of chronic disease. Anaemia of chronic disease thus caused 77% and iron deficiency anaemia 23% of observed anaemia. Recovery from anaemia occurred in 42% of the patients with anaemia of chronic disease and in 72% of iron depleted patients after iron supplementation. Anaemic patients, particularly those with anaemia of chronic disease, had a significantly greater number of the American College of Rheumatism criteria for RA, significantly more erosive joint damage, and significantly increased concentrations of serum rheumatoid factor than patients without anaemia. CONCLUSION: Anaemia appeared as a frequent and dynamic manifestation. Recovery and recurrence of anaemia was observed throughout follow up, leading to a longstanding and relatively high prevalence of the condition. Iron deficiency was diagnosed frequently and follow up revealed a considerable overlap with anaemia of chronic disease, making this the most important cause of anaemia in RA. Recovery from anaemia occurred more frequently in iron depleted anaemic patients than in those with anaemia of chronic disease. Anaemic patients, particularly those with anaemia of chronic disease, seemed to have a more serious course of their RA compared with non-anaemic patients.  相似文献   
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Injury to renal tubules and interstitium occur in various glomerular diseases, leading to functional impairment. Tubular basement membrane (TBM) is an important component in maintaining tubular epithelial cell integrity. Because ultrastructural changes in these structures had not been studied in detail, the authors analyzed 30 patients with various types of glomerular diseases, including minimal change disease (MCD), focal segmental glomerular sclerosis, IgA nephropathy, diffuse proliferative glomerulonephritis, membranous nephropathy, and lupus nephritis, by light, electron, and immunofluorescence microscopy. Ultrastructural changes in the TBM were studied and morphometric measurements were performed. The tubular basement membranes showed membranous structures, lucent or lytic areas, and tubular epithelial detachment. There was significant linear correlation between these tubular basement membrane changes and terminal complement complex neoantigens. The interstitial widening was due to banded collagen fibers, with anchoring fibers in the TBM. The various glomerular diseases lead to tubulointerstitial damage via changes in the TBM, leading to renal dysfunction.  相似文献   
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Psychiatric Quarterly - Patients who abscond from acute inpatient psychiatric wards put themselves and others at risks of variable nature and severity. There is a limited understanding of what...  相似文献   
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