We studied the spin-transfer switching probability (P sw ) in giant magnetoresistance (GMR) device with perpendicular magnetizations using short nanosecond and sub-nanosecond current pulses. A ...switching time of 510 picoseconds was achieved with the application of 7.5 mA, which is 4.3 times larger than the critical current at 0 K, without the application of an assisting magnetic field. Experiments with longer pulses revealed an exponential decay of the nonswitching probability (1-P sw ) as a function of pulse width. Extrapolation of the results predicts an error rate of 10 -19 for a pulse width of about 4.8 ns. To understand the observed pulse width dependence of P sw , we developed a formula using a macro spin model for the perpendicular magnetization system which includes the influence of thermal fluctuations in the initial magnetization direction of the free layer. The formula easily reproduces the qualitative nature of the observed P sw distributions in all time ranges.
The impact of ribavirin exposure on virologic relapse remains controversial in combination therapy with pegylated interferon (Peg‐IFN) and ribavirin for patients with chronic hepatitis C (CH‐C) ...genotype 1. The present study was conducted to investigate this. Nine hundred and eighty‐four patients with CH‐C genotype 1 were enrolled. The drug exposure of each medication was calculated by averaging the dose actually taken. For the 472 patients who were HCV RNA negative at week 24 and week 48, multivariate logistic regression analysis showed that the degree of fibrosis (P = 0.002), the timing of HCV RNA negativiation (P < 0.001) and the mean doses of ribavirin (P < 0.001) were significantly associated with relapse, but those of Peg‐IFN were not. Stepwise reduction of the ribavirin dose was associated with a stepwise increase in relapse rate from 11% to 60%. For patients with complete early virologic response (c‐EVR) defined as HCV RNA negativity at week 12, only 4% relapse was found in patients given ≥12 mg/kg/day of ribavirin and ribavirin exposure affected the relapse even after treatment week 12, while Peg‐IFN could be reduced to 0.6 μg/kg/week after week 12 without the increase of relapse rate. Ribavirin showed dose‐dependent correlation with the relapse. Maintaining as high a ribavirin dose as possible (≥12 mg/kg/day) during the full treatment period can lead to suppression of the relapse in HCV genotype 1 patients responding to Peg‐IFN alpha‐2b plus ribavirin, especially in c‐EVR patients.
Electron irradiation effects on the phase stability and microstructure change of conventional Zr66.7Cu33.3 amorphous alloy and Zr65.5Al7.5Cu27.5 metallic glass were examined. The amorphous phase was ...unstable under electron irradiation at 298 K and f.c.c.-Zr2Cu precipitates were formed. Although b.c.t.-Zr2Cu with coarse grains precipitated from the amorphous phase by thermal annealing, a nanocrystalline structure composed of f.c.c.-Zr2Cu precipitates and amorphous matrix was obtained by electron irradiation. There was a threshold total dose density for electron irradiation induced crystallization. The density for Zr65.0A17.5Cu27.5 was larger than that for Zr66.7Cu33.3. The b.c.t.-Zr2Cu precipitates in thermal equilibrium were unstable under electron irradiation and were transformed to f.c.c.-Zr2Cu through the amorphous phase.
Inhaled corticosteroids (ICS) and long-acting inhaled bronchodilators (IBD) are beneficial for the management of COPD. Although ICS has been reported to increase the risk of pneumonia in patients ...with COPD, it remains controversial whether it influences mortality. Using a Japanese national database, we examined the association between preadmission ICS therapy and in-hospital mortality from pneumonia in patients with COPD.
We retrospectively collected data from 1,165 hospitals in Japan on patients with COPD who received outpatient inhalation therapy and were admitted with pneumonia. Patients were categorized into those who received ICS with IBD and those who received IBD alone. We performed multivariate logistic regression analysis to examine the association between outpatient ICS therapy and in-hospital mortality, adjusting for the patients' backgrounds.
Of the 7,033 eligible patients, the IBD alone group (n=3,331) was more likely to be older, have lower body mass index, poorer general conditions, and more severe pneumonia than the ICS with IBD group (n=3,702). In-hospital mortality was 13.2% and 8.1% in the IBD alone and the ICS with IBD groups, respectively. After adjustment for patients' backgrounds, the ICS with IBD group had significantly lower mortality than the IBD alone group (adjusted odds ratio, 0.80; 95% confidence interval, 0.68-0.94). Higher mortality was associated with older age, being male, lower body mass index, poorer general status, and more severe pneumonia.
Outpatient inhaled ICS and IBD therapy was significantly associated with lower mortality from pneumonia in patients with COPD than treatment with IBD alone.
Polycrystalline merlinoite (MER) zeolite membranes were synthesized using K-MER, K-CHA and Na-PHI seed crystals to clarify the effect of the seed species on the water/ethanol separation performance ...of the membranes. The powdered seed crystals of 2–4
g/m
2 were implanted on the porous mullite tubular substrates. The secondary growth of MER membranes was carried out hydrothermally at 140
°C for 12
h. X-ray diffraction (XRD) patterns showed that the synthesized membranes have MER structures. Scanning electron microscope (SEM) observations revealed that the MER membranes comprised the block of the MER column particles with the densely packed nanoparticle zone near the substrate. Transmission electron microscopic (TEM) observation and electron diffraction patterns revealed that some of the nanoparticles still had the structures of the seed species. The MER membranes showed hydrophilic behavior in pervaporation (PV) measurements; however, in the measurement of single-component permeation, peculiarly high ethanol permeation was only observed in the case using Na-PHI-seeded membranes, which is likely due to the structural change of the PHI phase caused by dehydration. Therefore, we suggested that the ethanol permeation was affected by the bottom nanoparticle zone in the membrane, and the water selectivity was mainly due to the outer polycrystals zone. Since the CHA- and Na-PHI-seeded MER membrane showed higher performances at 40
°C (in spite of their roughness compared to the membrane using MER seed), it was suggested that the water permeation was strongly affected by adsorption, and the seeded zone plays the role of a molecular sieve.
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