Effect of mesoscopic inhomogeneities on the critical current of bulk melt-textured YBCO

The downsizing 211-inclusions and an increase of their density leads to rise in mean critical current value in Y-based melt textured material. Very often 211-inclusion are spread in the material volume non-homogeneous, with typical scale 50 - 100 micrometer. Therefore it is difficult to find the real correlation between local critical current and the inclusions distribution. We performed a study of a local critical current using modified magneto-optic technique on a melt-textured YBaCuO ceramic, found the areas with constant current and studied the real structure of the material in the areas, inclusions distribution and their sizes, by scanning electron microscopy and X-ray microanalysis. The estimation of a pinning in these places, by taking into account the amount of inclusions and the length of their boundaries, and comparison with the value of local critical current reveals a strait correlation between the density of inclusions and the current but shows remarkable quantitative disagreement.Comment: PDF (8 pages, 4 figures

Comparing the effects of different dietary organic acids on the growth, intestinal short-chain fatty acids, and liver histopathology of red hybrid tilapia (Oreochromis sp.) and potential use of these as preservatives

Dietary organic acids are increasingly being investigated as a potential means of improving growth and nutrient utilization in aquatic animals. A 9-week study was performed to compare equal amounts (2%) of different organic acids (sodium butyrate, acetate, propionate, or formate) on the growth, muscle proximate composition, fatty acid composition, cholesterol and lipid peroxidation, differential cell counts, plasma biochemistry, intestinal short-chain fatty acid (SCFA) level, and liver histopathology to red hybrid tilapia (Oreochromis sp.) (initial mean weight of 2.87 g). A second experiment was performed to determine their effects on lipid peroxidation and trimethylamine (TMA) when added at 1% to tilapia meat and left out for 24 h. The results of the first experiment showed no treatment effect to growth, feeding efficiencies, or muscle fatty acid composition, but all dietary organic acids significantly decreased intestinal SCFA. Dietary butyrate and propionate significantly decreased muscle lipid peroxidation compared to the control group, but the dietary formate treatment had the lowest lipid peroxidation compared to all treatments. Muscle crude protein and lipid in tilapia fed the formate diet were significantly lower and higher, respectively, and showed evidence of stress based on the differential cell counts, significantly higher plasma glucose and liver glycogen, as well as inflammatory responses in the liver. Although a potential benefit of dietary organic acids was a reduction to lipid peroxidation, this could be accomplished post-harvest by direct additions to the meat. In addition, inclusions of butyrate and propionate to tilapia meat significantly decreased TMA, which might be a more cost-effective option to improve the shelf life of tilapia products

Interventional Cardiologists of the T. The risk of stent thrombosis in patients with acute coronary syndromes treated with bare-metal and drug-eluting stents

ObjectivesWe aimed to evaluate the risk of definite stent thrombosis with bare-metal stents (BMS) and drug-eluting stents (DES) in patients treated for acute coronary syndromes.BackgroundAcute coronary syndromes (ACS) have been reported as increasing the risk for stent thrombosis.MethodsBetween January 2000 and December 2005, 5,816 consecutive patients underwent percutaneous coronary intervention for de novo lesions with a single stent type. These patients consisted of 3 sequential groups of BMS (n = 2,248), sirolimus-eluting stents (n = 822) and paclitaxel-eluting stents (n = 2,746). In total, 3,485 patients presented with an ACS.ResultsAfter a median follow-up of 1,394 days, patients with ACS had a definite stent thrombosis rate of 2.5% versus 1.0% in patients with stable angina (propensity score-adjusted hazard ratio [HR]: 2.80, 95% confidence interval [CI]: 1.72 to 4.56). ACS patients had a higher risk of early and late stent thrombosis, although the increased risk of very late stent thrombosis was only present in ACS patients treated with DES. In stable patients, any stent thrombosis resulted in a significant increase in mortality (adjusted HR: 4.0, 95% CI: 1.7 to 9.3), although this was particularly evident for late or very late stent thrombosis; in contrast only early stent thrombosis significantly increased mortality in patients with acute coronary syndrome patients (adjusted HR: 2.0, 95% CI: 1.0 to 4.1).ConclusionsPatients with acute coronary syndromes are at higher risk of early and late stent thrombosis with either BMS or DES, although very late stent thrombosis seems to be uniquely associated with DES. The clinical sequelae of late and very late stent thrombosis are more pronounced in stable patients