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Objectives No randomized controlled trials have evaluated the comparative outcomes of cefazolin versus nafcillin for methicillin-susceptible Staphylococcus aureus (MSSA) bacteraemia. Methods A prospective observational cohort study including all S. aureus bacteraemia was conducted at 10 hospitals. Patients (≥15 years) with MSSA bacteraemia who received cefazolin or nafcillin as definitive antibiotics were included. The rates of treatment failure (premature discontinuation of antibiotics because of adverse effects, switching of antibiotics because of clinical failure, all-cause mortality within 1 month, or recurrence) were compared between the cefazolin and nafcillin groups. Propensity score matching analyses were performed to balance the factors influencing the selection of antibiotics. Results Among the 242 included cases, the bones and joints (36.8%) were the most common sites of infection and 60.7% of the patients had sepsis. The overall treatment failure rate was 43.8% (106/242). All-cause mortality within 1 month was 6.2% (15/242). After propensity score matching, the treatment failure rate of cefazolin was lower than that of nafcillin (30.4% (24/79) vs. 49.4% (39/79), p 0.015) because of a higher rate of discontinuation caused by adverse events. When the data were limited to patients with sepsis, the treatment failure rates of both groups were not significantly different. Approximately 22% (24/110) of MSSA isolates exhibited a cefazolin-inoculum effect (CIE) that had significant impact on the failure rate and mortality of the cefazolin group. Conclusions Cefazolin might be recommended as an adequate and better-tolerated treatment for MSSA bacteraemia in the absence of CIE.

To assess the outcome of Staphylococcus aureus bacteraemia (SAB) according to factors associated with necessity for longer treatment in conjunction with the duration of treatment.We prospectively collected the data of patients with SAB consecutively during 12 to 39 months from 11 hospitals. If multiple episodes of SAB occurred in one patient, only the first episode was enrolled. Factors associated with necessity for longer treatment were defined as follows: persistent bacteraemia, metastatic infection, prosthesis and endocarditis. If any of the factors were present, then the case was defined as longer antibiotic treatment warranted (LW) group; those without any factors were defined as shorter antibiotic treatment sufficient (SS) group. Poor outcome was defined as a composite of 90-day mortality or 30-day recurrence. Duration of antibiotic administration was classified as14 or ≥14 days in the SS group and28 or ≥28 days in the LW group.Among 2098 cases, the outcome was analysed in 1866 cases, of which 591 showed poor outcome. The SS group accounted for 964 cases and the LW group for 852. On multivariate analysis, age over 65 years, pneumonia, higher Sequential Organ Failure Assessment (SOFA) score and chronic liver diseases were risk factors for poor outcome. Administration of antibiotics less than the recommendation was associated with poor outcome, but this significance was observed only in the LW group (adjusted odds ratio = 1.68; 95% confidence interval, 1.00-2.83; p 0.05).Inappropriately short antibiotic treatment was associated with poor outcome in the LW group. Vigilant evaluation for risk factors to determine the duration of treatment may improve the outcome among patients with SAB.

In this study, the influence of workrest positions on the deflection of a crankshaft is investigated, in order to enhance the machining precision in orbital grinding. Crankshafts of 3m, 5m and 8m are selected, and three types of states (no machining, journal machining and pin machining) are studied. The model is simplified with stiffnesses applied to the stock instead of real contact between workrest and stock. As the workrests are positioned to the machining region, the deflection of the machined stock is reduced. Pin machining shows more stable result than journal machining.

The Ti incorporation at Fe-site in the double perovskite lattice of (SFNO) system is studied. The Ti concentration optimization yielded an efficient photocatalyst. At an optimum composition of Ti as x = 0.07 in , the photocatalyst exhibited 2 times the quantum yield for photolysis of in presence of , than its undoped counterpart under visible light (). Heavily Ti-doped lattice exhibited poor photochemical properties due to the existence of constituent impurity phases as observed in the structural characterization, as well as deteriorated optical absorption. The higher electron-density acquired by n-type doping seem to be responsible for the more efficient charge separation in (0.05

This study was carried out to evaluate acid depositions and to understand their effect. Wet precipitation has been collected at twenty-four sites in Korea for one year of 1999. The ion concentrations such as H+, Na+, K+, Mg2+, NH4 +, Ca2+, Cl−, NO3 − and SO4 2− were chemically analyzed and determined. Precipitation had wide range of pH(3.5∼8.5), and volume-weighted average was 5.2. The contribution amounts of Cl−, SO4 2− and NO3 − in anion were shown to be 54%, 32%, and 14%, respectively and those of Na+ and NH4 + in cation were 32% and 25%. The ratios of Cl− and Mg2+ to Na+ in precipitation were similar to those of seawater, which imply that great amount of Cl− and Mg2+ in precipitation could be originated from seawater. The concentration of H+ is little related with SO4 2−, NO3 − and Cl− ions, whereas nss−SO4 2− and NO3 − are highly correlated with NH4 +, which could suggest that great amount of SO4 2− and NO3 − exist in the form of ammonium associated salt. The annual wet deposition amounts (g m−2year−1) of SO4 2−, NO3 −, Cl−, H+, NH4 +, Na+, K+, Ca2+ and Mg2+ were estimated as 0.88∼4.89, 0.49∼4.37, 0.30∼9.80, 0.001∼0.031, 0.06∼2.15, 0.27∼4.27, 0.10∼3.81, 0.23∼1.59 and 0.03∼0.63.

The surface chemical bonding states and the ferroelectric properties of sol-gel deposited lead zirconate titanate Pb(Zr 0.52 Ti 0.48 )O 3 , PZT] thin films coated on (111)Pt/Ti/SiO 2 /Si substrates were investigated. X-ray photoelectron spectroscopy (XPS) was used to determine the oxidation state of the surface and the chemical composition as a function of depth in ferroelectric PZT thin layers. Values for the dielectric constant and dissipation factor at I kHz for the 300 nm-thick film were 1214 and 0.014 for the film annealed at 520 °C, and 881 and 0.015 for a film annealed at 670 °C. Measured values for the remanent polarization (P r ) and coercive field (E c ), from polarization-electric field (P-E) hysteresis loops biased at 10 V at a frequency of 100 Hz, were 16.7, 14.4 μC/cm 2 and 60, 41.7 kV/cm for 520 °C and 670 C. The leakage current density (J) was 72 and 96 nA/cm 2 at an applied field of 100 kV/cm. It was found that the bonding states of lead and oxygen in the surface regions could be correlated with the ferroelectric properties of the integrated thin layers.

Epitaxial thin films of Pb(Zr 0.53 Ti 0.47 )O 3 (PZT) and LaNiO 3 (LNO) have been grown by sol-gel method on (100)LaAlO 3 and (100)SrTiO 3 substrates. Structural, surface morphological, and ferroelectric properties of PZT deposited on LNO electrode were investigated. X-ray diffraction patterns including phi-scan exhibit that epitaxial PZT and LNO thin films can be grown at an annealing temperature as low as 700°C with good crystallinity and no presence of secondary phases. The ferroelectric properties of the PZT films are observed through the P-E hysteresis loop and C-V curves. The average P r and E c were 28 μC/cm 2 and 35 kV/cm, respectively at an applied electric field of 300 kV/cm. The films exhibited good fatigue characteristics under bipolar stressing. The piezoelectric coefficient of the films was 270 pC/N by a single beam interferometer technique.

Electrically conductive LaNiO3 (LNO) and ferroelectric Pb(Zr0.52Ti0.48)O3 (PZT) thin films were deposited on single crystal (100)SrTiO3 (STO), (100)LaAlO3 (LAO), and Pt/Ti/SiO2/Si(100) substrates using solution deposition routes. X-ray diffraction and scanning electron microscopy were used to investigate the crystallinity and microstructure of the films. The surface bonding states of the PZT and LNO films were determined by X-ray photoelectron spectroscopy (XPS). The average room-temperature dielectric constant of the PZT films, measured at 1 kHz, was in the range 905–1002 and the dissipation factor was below 0.03 for all films. The remnant polarization and coercive electric field of the PZT/LNO films deposited on (100)STO, (100)LAO, and Pt/Ti/SiO2/Si substrates were 30, 32 and 19 μC/cm2, and 84, 87 and 57 kV/cm, at applied electric field of 450 kV/cm, respectively.

Lead scandium niobate titanate (Pb[Sc 1/2 Nb 1/2 ) 0.57 Ti 0.43 ]O 3 ) thin films with 0.5 mol% Nb doping were prepared by a sol–gel method. Films annealed at temperatures greater than 600°C crystallized into a single phase perovskite structure. The films were transparent and crack-free with uniform thickness and an average grain size of 1.1 μm. The dielectric constant and dissipation factor measured at 1 kHz for a film annealed at 700°C were 1370 and 0.022, respectively. Ferroelectricity was confirmed by the presence of hysteresis loops, with a remanent polarization of 20 μC/cm 2 and coercive field of 35 kV/cm. The piezoelectric coefficient ( d 33 ) of a poled film was 98 pm/V. Dielectric, ferroelectric, and piezoelectric properties of the films were enhanced through annealing and poling after deposition of the top gold electrode.