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Notes: Surface-energy-induced secondary or tertiary recrystallization by grains with a specific surface plane can be freely governed in thin-gauged 3% Si–Fe strips by controlling the bulk content of sulfur and annealing atmosphere. During a vacuum or hydrogen annealing process, a convex profile in segregated-sulfur concentration is formed due to evaporation or desorption of segregated sulfur as a hydrogen sulfide, corresponding to a trough in magnetic induction. High magnetic induction is obtained after the annealing treatments. Final annealing under an argon atmosphere caused a saturation in segregated-sulfur concentration with annealing time. Under this extremely high segregated sulfur, grains of high index crystal plane including {111} continued to grow, resulting in low magnetic induction. © 2000 American Institute of Physics.

Notes: Neural network is considered as a parameter estimation tool in plasma controls for next generation tokamak such as ITER. The neural network has been reported to be so accurate and fast for plasma equilibrium identification that it may be applied to the control of complex tokamak plasmas. For this application, the reliability of the conventional neural network needs to be improved. In this study, a new idea of double neural network is developed to achieve this. The new idea has been applied to simple plasma position identification of KSTAR tokamak for feasibility test. Characteristics of the concept show higher reliability and fault tolerance even in severe faulty conditions, which may make neural network applicable to plasma control reliably and widely in future tokamaks. © 2001 American Institute of Physics.

Notes: A Thomson scattering system on the Hanbit magnetic mirror device has been installed to measure the electron temperature and density of the plasma in the central cell. The configuration is based on a standard 90° scattering scheme. The optical system consists of a Q-switched Nd:YAG laser, input optics, collection optics, spectrograph optics, detectors, and a data acquisition system. Although the laser beam path is about 50 m long and the background emissions are not low, the electron temperature measurements have been made at a single point on a shot-by-shot basis, in which the stray light was considerably suppressed by using a beam dump, a viewing dump, and baffles. The measured electron temperature is about 50–70 eV in experiments for plasma production and heating by ICRF of 200-kW-rf power using a slot antenna. A description of the installed system and the experimental results are presented. © 2001 American Institute of Physics.

Notes: With the introduction of high pressure balloon inflations and antiplatelet therapy, the incidence of stent thrombosis has been markedly reduced, but the incidence of late stent restenosis has not. A new strategy may be local drug delivery, which maintains sustained local concentration and limits systemic complications. To evaluate the efficacy of local nitric oxide (NO) donor delivery on stent thrombosis and complications, local NO donor delivery was performed in stented patients. NO donor (2.0-mg molsidomine) was delivered (1.0 mL/min 〉 10 min) using the Dispatch Catheter after predilation of target lesions in 13 patients (6 angina, 7 myocardial infarction, age 53.1 ± 11.4 years). After local NO donor delivery, Palmaz-Schutz stents were placed using standard methods. Follow-up coronary angiograms were performed 48 hours and 6 months after stenting. None of the patients had hypotensive effects, ischemic symptoms, or ECG changes during and after local NO donor delivery. APTT and CK values were unchanged at 3 and 24 hours after local NO donor delivery and stenting. Follow-up coronary angiograms at 48 hours and 6 months showed all stents patent with TIMI III flow and without intrastent thrombus. No target lesion revascularization and 100% event-free survival were observed during the 6-month clinical follow-up period. Intracoronary stenting may be performed safely and effectively by local NO donor delivery prior to stent implantation.

Notes: Abstract: Many different stimuli such as bioactive agents and environmental stresses are known to cause the activation of sphingomyelinase (SMase), which hydrolyzes sphingomyelin to generate ceramide as a second messenger playing a key role in differentiation and apoptosis in various cell types. Here we identified multiple forms of the membrane-associated neutral SMase (N-mSMase) activity in bovine brain. They could be classified into two groups according to extracting agents: group T-mSMase, extracted with 0.2% Triton X-100, and group S-mSMase, extracted with 0.5 M (NH4)2SO4. Group T-mSMase: α, β, γ, and δ, which were extensively purified from 40,000-g pellets of bovine brain homogenates by 3,150-, 5,275-, 1,665-, and 2,556-fold over the membrane extracts, respectively, by sequential use of several column chromatographies. On the other hand, S-mSMase was eluted as two active peaks of S-mSMase ε and ζ in a phenyl-5PW hydrophobic HPLC column and further purified by 1,119- and 976-fold over 40,000-g pellets of the homogenates, respectively. These highly purified N-mSMase enzyme preparations migrated as several bands on sodium dodecyl sulfate-polyacrylamide gel electrophoresis and showed many different features in biochemical properties such as pH dependence, Mg2+ requirements, and effects of detergents. Taken together, our data strongly suggest that mammalian brain N-mSMase may exist as multiple forms different in both its chromatographic profiles and biochemical properties.

Notes: Abstract: Previously we reported that immunostimulated astrocytes were highly vulnerable to glucose deprivation. The augmented death was mimicked by the peroxynitrite (ONOO--producing reagent 3-morpholinosydnonimine (SIN-1). Here we show that glucose deprivation and ONOO- synergistically deplete intracellular reduced glutathione (GSH) and augment the death of astrocytes via formation of cyclosporin A-sensitive mitochondrial permeability transition (MPT) pore. Astrocytic GSH levels were only slightly decreased by glucose deprivation or SIN-1 (200 μM) alone. In contrast, a rapid and large depletion of GSH was observed in glucose-deprived/SIN-1-treated astrocytes. The depletion of GSH occurred before a significant release of lactate dehydrogenase (a marker of cell death). Superoxide dismutase and ONOO- scavengers completely blocked the augmented death, indicating that the reaction of nitric oxide with superoxide to form ONOO- was implicated. Furthermore, nitrotyrosine immunoreactivity (a marker of ONOO-) was markedly enhanced in glucose-deprived/SIN-1-treated astrocytes. Mitochondrial transmembrane potential (MTP) was synergistically decreased in glucose-deprived/SIN-1-treated astrocytes. The glutathione synthase inhibitor L-buthionine-(S,R)-sulfoximine markedly decreased the MTP and increased lactate dehydrogenase (LDH) releases in SIN-1-treated astrocytes. Cyclosporin A, an MPT pore blocker, completely prevented the MTP depolarization as well as the enhanced LDH releases in glucose-deprived/SIN-1-treated astrocytes.

Notes: The effects of heating rate and surface oxidation on magnetic induction of thin-gauged 3% Si–Fe strips have been investigated. Magnetic induction increased with increasing final annealing temperature. Before and after 1150 °C, the planar orientation of grains shifted from (100)[011] to (110)[001], resulting in magnetic induction higher than 1.90 T. Magnetic induction after final annealing was higher in case of a faster heating rate. This is because enough time for growth of (110) grains is given in the case. Irrespective of transient annealing temperature, magnetic induction after final annealing was mostly higher than 1.90 T. A maximum, 1.97 T, was obtained at a transient annealing temperature of 800 °C. This is because iron oxide formed at 800 °C inhibited the surface-energy-induced selective growth of (100)[011] grains during heating up to 1200 °C. © 2000 American Institute of Physics.

Notes: To improve inherent shortcomings of statistical methods and apply them to the extraction of plasma equilibrium parameters in a fast timescale for real-time plasma control, new concepts of statistical methods such as principal component analysis-based neural network (NN), functional parametrization (FP)-based NN and double network are introduced by modifying NN and FP. These new methods are benchmarked and compared with the conventional techniques of NN and FP in a simple single-filament system. As a result of their applications to identification of plasma equilibrium parameters in the Korea Superconducting Tokamak Advanced Research tokamak, particularly, the double network concept among them has successfully achieved the improvement of drawbacks in the conventional methods. It is shown that more reliable results from the double network method can be obtained by combining several different statistical treatments as a primary network. Even in the case of nonoptimized methods united as a primary network, quite acceptable results can be achieved in the double network method. © 2001 American Institute of Physics.

Notes: Background/aims: The autofluorescence spectrum of skin consists of a number of overlapping single spectra emitted by fluorescent molecules. The overlapping makes it difficult to distinguish changes in the overall spectrum and the molecular basis for it. We applied curve fitting analysis to decompose the autofluorescence spectrum of normal human skin and studied the variation in different body sites.Methods: Skin autofluorescence spectra were obtained in vivo from the normal skin of 17 subjects, using 5 excitation wavelengths: 340, 350, 360, 370 and 380 nm. The spectra were displayed in the wavelength range of 400 nm to 800 nm. Curve fitting was performed for each spectrum using the Levenberg–Marquardt algorithm.Results: The skin autofluorescence spectra, provoked by all the excitation wavelengths, consisted of three component bands with center wavelengths at 450 nm, 520 nm and 625 nm. The 450 nm band contributed about 75% to the intensity of the overall spectrum, the 520 nm band contributed 25%, and the 625 nm band contributed about 2%. The three bands may correspond mainly to the fluorescence of nicotinamide adenine dinucleotide (NADH), flavin adenine dinucleotide (FAD), and porphyrins. Significant differences were found between the spectra of forehead and buttock skin. In forehead skin, the 625 nm band contributed more to the intensity of the overall spectrum, while the 450 nm and 520 nm bands had much lower peak heights, and the 450 nm and 625 nm bands were broader.Conclusions: The autofluorescence of skin is an overlapped spectra of molecules such as NADH, FAD, and porphyrins. These molecules contribute differently to the overall spectrum in different body sites.

Notes: SUMMARY: Pharmacokinetic studies were performed in 10 stable kidney transplantation patients who received microemulsion formulation (Neoral®) of cyclosporine A (CsA) twice daily. No agents having pharmacokinetic effects on CsA had been used in these patients. The values of various basic pharmacokinetic parameters were similar to those reported in Western literature. The complete area under the blood concentration–time curve (AUC) of CsA for the duration of 12 h (12-h AUC) was determined using the linear trapezoidal rule from seven concentrations at 0, 1, 2, 4, 6, 8, and 12 h after CsA administration. The mean values of 12-h AUC were 4603.63 ± 344.61 ng h/mL. CsA concentrations at 2 h after dosing (not the trough levels) showed the best correlation with the complete AUC (r2 = 0.9322). The abbreviated AUC of CsA was calculated either by stepwise multiple linear regression analysis or by the linear trapezoidal rule from a few sampling time points. Using stepwise multiple linear regression analysis, which was used in calculating abbreviated AUC in all previous studies, the model equation that had the highest correlation and the lowest prediction error with the complete AUC was derived by using CsA concentrations at 2 and 8 h after dosing (12-h AUC = 4.262C2 + 8.390C8− 669.417; r2 = 0.9808, absolute prediction error = 3.97 ± 0.96). Two model equations derived using the linear trapezoidal rule provided the best correlation with the complete AUC: (1) The two time points selected model equation 12-h AUC = 4C2 + 5C8; r2 = 0.9780, absolute prediction error = 6.41 ± 1.22). (2) The three time points selected model equation 12-h AUC = 4C0 + 3C2 + 5C6; r2 = 0.9475, absolute prediction error = 5.00 ± 1.41). When different pharmacokinetic data sets were applied to the model equations derived using regression analysis, the values of coefficients and the constant of the regression equation had changed from the initial equation. Thus, new model equations will emerge every time the new data are applied. In contrast, the values of coefficients in the model equation calculated using trapezoidal rule were unaltered when tested by the new pharmacokinetic data set. Thus, the abbreviated AUC derived using the linear trapezoidal rule would be simpler than and superior to that obtained using stepwise multiple linear regression analysis in prediction of the complete AUC.