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We numerically investigated the effect of a duct on propeller performance. Numerical simulations were performed for a wide range of diameters ( 0.7 D ≤ D D ≤ 1.0 D ) and angles of attack of the duct ( 0 ° ≤ θ ≤ 20 ° ), where D is the propeller diameter. The duct profile is NACA0015 whose chord length is 0.3 D and trailing edge is located 0.2 D upstream from the center of the propeller. The propeller force coefficients presented the same increasing pattern and the rate of the propeller efficiency with the duct to the bare propeller augments with increasing θ , irrelevant to D D . However, the net thrust reflecting the total drag, including the duct, depends on the duct size. Hence, there is a critical value of θ such that the magnitude of the total drag becomes maximum for a relatively large duct size. A certain size of duct leads two regions of the inflow into the propeller, which is originated by the duct. One is the inner region of the duct where the high-speed flow exists because of the contraction of the duct. Another is the outer region of the duct where the flow decelerates due to the duct wake. The circumferential locality of the axial velocity becomes weaker with increasing θ due to the accelerated flow along the axial direction. Eventually, lower and higher pressure coefficients on the suction- and pressure-side surfaces, respectively, cover a much wider area than those of the case without the duct, leading to greater thrust and torque. [ABSTRACT FROM AUTHOR]

An abstract of the study "Chronotropic effect of cilostazol on left ventricular function after acute myocardial infarction," by S. H. Lee and colleagues is presented.

Numerical study of three-dimensional unsteady flow behind the double wavy (DW), singe wavy (SW), and smooth circular (SC) cylinders geometry at subcritical Reynolds number (R e = 3.0 × 10 3) using large-eddy simulations based on the finite volume method are investigated in this study. This study contributes to the understanding of the effects of geometric disturbances as a passive flow control method to reduce the hydrodynamic forces exerted by the fluid flow on the cylinders. The DW and SW cylinders with spanwise wavelength ratios as λ / D m = 3.79 − 6.82 and with fixed wave amplitude ratio as a / D m = 0.152 are investigated and compared with SC cylinder in terms of flow variables such as drag, lift coefficients, Strouhal number, vortex formation length, and vorticity contours of the cylinders. Furthermore, an investigation was also carried out to quantify the differences in the fluid flow properties behind SC and SW cylinders compared to DW cylinders. When compared to the SC and SW cylinders, the findings indicated that the DW cylinder reduces drag and lift coefficients significantly for every λ / D m. A maximum reduction in fluid forces is observed at λ / D m = 6.06 for DW cylinder; 16.63% and 94.99% reduction in mean drag and lift fluctuations respectively compared to SC cylinder. The DW cylinder also showed a longer vortex formation length than SC and SW cylinders for every λ / D m. The flow separation angle and mean streamwise velocity distributions are also investigated and compared between the SC, SW, and DW cylinders. The present study reveals that the geometric surface waviness of the cylinder can be used to minimize force coefficients at a sub-critical flow regime. The obtained conclusions could provide some references to the engineering field for the design stage of slender marine structures. • Five different cylinders, each for single wavy and double wavy, were modeled based on wavelength ratios. • Flow around the single wavy, and double wavy cylinders were numerically investigated. • Hydrodynamic coefficients and flow features were compared between smooth, single wavy and double wavy cylinders. • An optimal wavelength each for single wavy and double wavy cylinders is presented. • The double wavy cylinder achieved more reduction in hydrodynamic coefficients than single wavy and smooth circular cylinders. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the changes in serum creatinine and total CO2 levels in patients receiving metformin during administration of contrast medium.Materials and Methods: Patient records from January 2012 to December 2012 after the administration of contrast medium were reviewed retrospectively. A total of 924 patients were included for the final analysis. Of them, 105 received metformin during contrast medium administration, 112 were taking other oral hypoglycaemic agents, and 707 patients were not diabetic (controls).Results: No significant change in total CO2 levels was detected (p=0.678). Metabolic acidosis was present in 33 (31.4%) metformin users, 31 (28.6%) other oral hypoglycaemic agent users, and 153 (21.6%) control patients. In the present logistic regression analysis, age, baseline levels of creatinine, and total CO2 levels were associated with metabolic acidosis after contrast medium exposure.Conclusion: These data indicate the presence of a coexisting risk factor, other than metformin use, associated with metabolic acidosis after contrast medium exposure. No relationship was found between the use of metformin and metabolic acidosis during contrast medium exposure. [ABSTRACT FROM AUTHOR]

Background ABO-incompatible organ transplants are good options for expanding the living donor pool; however, the necessary pre-conditioning to remove ABO antibodies before surgery can evoke critical infectious complications after surgery. Methods Between February 2009 and July 2013, we performed ABO-incompatible kidney transplantation on 182 patients. We analyzed the first 85 patients for post-operative infectious complications in a cross-sectional cohort of patients (group 1, n = 85) who had received an ABO-incompatible kidney transplant and, in light of the results, amended the pre-conditioning (lower dose of rituximab, selective use of calcineurin inhibitors, anti-metabolite reduction, and prophylactic strategy) given to a prospective cohort (group 2, n = 97). Results The characteristics of the two groups did not differ significantly. Infectious complications decreased significantly in group 2, including cytomegalovirus (anti-genemia 64.7% vs 27.8%, P < .001) and BK viremia (35.2% vs 18.6%, P = .008). The acute rejection rate and death-censored graft survival were similar in both groups. Notably, with the modified protocol, there were no deaths (8.2% vs 0.0%, P = .03). Conclusions Pre-conditioning for ABO-incompatible kidney transplantation is a prerequisite for successful outcome; its drawbacks can be limited with the use of a modified immunosuppressive strategy. If immunosuppression is modified according to host conditions, ABO-incompatible kidney transplantation can be performed safely with a successful graft outcome. [ABSTRACT FROM AUTHOR]

Abstract: We report the annealing temperature dependence of global and local structures of hydrothermally grown KNbO3 nanorods. With increasing annealing temperature, the amount of hydroxyl groups in the KNbO3 nanorods decreased and finally disappeared at about 800°C. Morphology of the nanorods seemed not to change significantly, however, X-ray intensity ratio between (022) and (200) planes, i.e., I 022/I 200, increased with decreasing lattice hydroxyl group contents. This result could be attributed to the fact that the hydroxyl groups were desorbed more effectively along the [011] direction than in other directions due to the elongated nanorod along the [011] direction. The frequencies of external and bending modes, besides stretching mode, showed red-shift with decreasing lattice hydroxyl group contents. This result implied that the lattice hydroxyl groups existed as interstitial defects near K ions. [Copyright &y& Elsevier]

Abstract: We investigate the structural and phase transition characteristics of hydrothermally grown KNbO3 and KTaO3 nanocrystals. Field emission scanning electron microscope and transmission electron microscope measurements clearly show that the KNbO3 crystal has a nanorod shape while the KTaO3 crystal has a nanocube shape. Fourier transform infrared spectroscopy measurement reveals the existence of a hydroxyl group in both nanocrystals. The hydroxyl group seems to be related to the enlarged lattice constants, the lowered structural phase transition temperatures, the broad phonon width and the increased number of Raman-active phonon modes in KNbO3 and KTaO3 nanocrystals. [Copyright &y& Elsevier]

Abstract: Electrodialysis (ED) is one of a number of attractive options in the desalination of secondary effluent, but membrane fouling is still an issue that needs to be resolved. This study investigated potential foulants and the fouling control of ED during desalination. Cation and anion exchange membranes were found to be fouled with different components in secondary effluent. Protein and calcium ion were the most responsible for the fouling of anion and cation exchange membranes, respectively. Pretreatment using iron oxide particles (IOPs) as an adsorbent contributed greatly to the reduction of irreversible fouling caused by organic matter present in the secondary effluent. IOP pretreatment also improved the quality of the treated water significantly. [Copyright &y& Elsevier]

Abstract: In this paper, a competition between a ferromagnetic metal and a charge/orbital-ordered insulator has been investigated for RE1− x AE x MnO3 () with RE and AE being rare earth elements, ranging from La to Gd, and alkaline earth elements, Ca, Sr and Ba, respectively. A phase diagram is deduced in the plane of the effective one-electron bandwidth versus the magnitude of quenched disorder, which can be controlled by the averaged value and the variance of the RE/AE ionic radii, respectively. In the vicinity of the phase boundary, the ferromagnetic transition temperature is critically suppressed, and the colossal magnetoresistance (CMR) is enhanced. [Copyright &y& Elsevier]

One patient experienced erythema after the third NB-UVB session and discontinued the therapy. Although interruption of fasting before phototherapy can be a confounding bias, our data demonstrated that the treatment duration of NB-UVB was shorter than that of other treatments. The patients in this manuscript have given written informed consent to the publication of their case details. [Extracted from the article]

Aim: To investigate whether the use of metformin during computed tomography (CT) with radiocontrast agents increases the risk of contrast-induced nephropathy (CIN) and metabolic acidosis after CT in type 2 diabetes patients with mild to moderate renal failure.Materials and Methods: Patient records from January 2015 to December 2017 were reviewed retrospectively. A total of 374 patients were included in the final analysis. Of them, 157 patients received metformin, and 217 patients were taking other oral hypoglycaemic agents (OHAs) during radiocontrast administration.Results: No significant difference in CIN incidence was observed between the metformin use group and the other OHAs group (p=0.085). Metabolic acidosis after CT was seen in 91 (58%) patients who used metformin and 141 (65%) patients who were taking other OHAs. There was no relationship between metabolic acidosis after CT and the use of metformin (p=0.195). Metabolic acidosis after radiocontrast agent exposure was associated with malignant disease, low serum albumin level, and low serum total CO2 level at baseline.Conclusion: These data show that other factors, but not metformin use, are associated with metabolic acidosis after radiocontrast agent exposure in patients with reduced renal function. These data support current recommendations that there is no need to discontinue metformin before CT using radiocontrast agents in patients with mild to moderate renal failure. [ABSTRACT FROM AUTHOR]

Highlights: [•] Introduction of oxygen vacancy in NaNbO3 sub-micron cube through the thermal annealing with Zr foil in vacuum. [•] Confirmation of the Pmc21symmetry for oxygen-deficient NaNbO3−δ . [•] Observation of coexistence of piezoelectricity and electric conduction in oxygen-deficient NaNbO3−δ sub-micron cubes. [Copyright &y& Elsevier]

Highlights: [•] Synthesis of BaTiO3/ZnFe2O4 core/shell nanoparticles. [•] Nanoparticles are ferromagnetic with spontaneous magnetization of 8emu/g. [•] Dielectric constant is found to increase with temperature. [•] About 1.3% change, in dielectric constant at 1T of magnetic field. [ABSTRACT FROM AUTHOR]

Abstract: Laser-induced breakdown spectroscopy (LIBS) has been recognized as a promising technique for analyzing sensitive nuclear materials such as uranium, plutonium, and curium in a high-radiation environment, especially since the implementation of IAEA (International Atomic Energy Agency) safeguards. The uranium spectra of ore samples were quantitatively analyzed prior to analyzing sensitive materials in the nuclear industry. The purpose of this experiment is to extract quantitative information about the uranium in a uranium ore using a standard addition approach. The uranium ore samples containing different concentrations of U were prepared by mixing raw ore powder with natural uranium oxide powders. Calibration sets of 0.2, 0.4, 0.6, 0.8 and 1.0wt.% uranium concentrations within the uranium ore sample were achieved. A pulsed and Q-switched Nd:YAG laser at a wavelength of 532nm was used as a light source. An echelle spectrometer that covers a 190–420nm wavelength range is used to generate a calibration curve and determine the detection limit of uranium in the ore matrix. The neutral atomic-emission peak at a wavelength of 356.659nm indicated a detection limit of ~158ppm for uranium, and the uranium concentration was determined in a raw ore sample that has an unknown quantity of uranium. [Copyright &y& Elsevier]

Abstract: The temperature variations of the elastic constant C 11 and the corresponding acoustic attenuation coefficient of barium titanate single crystals grown by two different methods in the paraelectric phase were obtained in a wide temperature by means of Brillouin light scattering. Two phenomenological approaches were adopted to attempt to explain the anomalous change in C 11 (denoted as ΔC 11) in the paraelectric phase. ΔC 11 exhibited a logarithmic variation as log[(T − T 0)/T 0] in a certain temperature range from T c to about T c +80°C instead of the other variation of (T − T 0) ζ predicted by the mean-field approach. This temperature range was almost the same as the range where precursor dynamics were theoretically predicted to set in. The fact that the logarithmic variation was proposed for uniaxial systems might indicate that the correlated deformation of precursor polar clusters is tetragonal, as was suggested from nuclear magnetic resonance study . [Copyright &y& Elsevier]

Abstract: We report the structural and photoluminescence characteristics of a high energy Ar+-irradiated SrTiO3 single crystal. High resolution X-ray reciprocal space mapping, cross-section scanning electron microscopy and photoluminescence measurements suggest that thick amorphous and oxygen-deficient SrTiO3 layers are formed after irradiation. Due to the highly accelerated Ar+ (∼100keV), electrical conductivity of the oxygen-deficient SrTiO3 layer seems to be highly reduced, which results in the absence of 440nm (blue-light) emission at 300K, and broad and weak 380nm emission at 20K. [Copyright &y& Elsevier]

Abstract: We have investigated the magnetoelectric and magnetodielectric properties of (1−x)Ba0.6Sr0.4TiO3–(x)La0.7Ca0.3MnO3 composites, where constituent Ba0.6Sr0.4TiO3 and La0.7Ca0.3MnO3 have nearly the same ferroelectric and ferromagnetic Curie temperatures. Below a percolation-limit sample, i.e., , we have observed a decrease of electrical polarization and an increase of dielectric constant with strong frequency dependences near when we turn on the magnet. On the other hand, we have observed little change of electrical polarization and a decrease of dielectric constant without frequency dependences at 10 K. We have attributed the observed magnetoelectric and magnetodielectric properties to the extrinsic magnetoresistance origin near and to the strain-induced magnetoelectric coupling at 10 K. [Copyright &y& Elsevier]

Abstract: We fabricate epitaxial terbium iron garnet (Tb3Fe5O12, TbIG) thin films on (110) gadolinium gallium garnet (Gd3Ga5O12, GGG) substrates using a pulsed laser deposition technique. High quality (110) oriented epitaxial growth of TbIG thin films has been revealed by θ–2θ scans, φ-scans, rocking curves (ω-scans), and reciprocal space mapping in high resolution X-ray diffraction. Magnetic and magneto-optic hysteresis loops, however, demonstrate that the easy axis of magnetization in these films is out-of-plane, i.e. along [110] instead of [1–11] direction, as sharp contrast to bulk. [Copyright &y& Elsevier]

Abstract: We have reported the epitaxial growth and the electric/magnetic properties of SrRuO3 and (La0.67Sr0.33)MnO3 thin films on Ba(Ti0.925Zr0.075)O3 substrates. The dielectric constant and thermal expansion of Ba(Ti0.925Zr0.075)O3 exhibited hysteretic jumps at the structural transition temperatures. Near the rhombohedral to orthorhombic structural transition temperature of Ba(Ti0.925Zr0.075)O3, which occurs at ∼33 °C, we have observed a drastic jump of resistivity and magnetization of the thin films. These results suggest that epitaxial perovskite oxide thin films on Ba(Ti0.925Zr0.075)O3 substrates should be quite useful for the strain-induced changes of physical properties near room temperature. [Copyright &y& Elsevier]

Abstract: The photoconductivity spectra of oxygen-deficient SrTiO3−δ thin films with Pt contacts show two intriguing peaks at and above the band gap (∼3.2 eV). The first (second) peak, located at (above) the band gap, shows hysteretic (linear) photocurrent–voltage characteristics with a long (short) relaxation time. In addition, the first (second) peak shows a weak (strong) dependence on the surface treatment of the substrate as well as the surrounding atmosphere. These results have been discussed in terms of the Schottky contact, built-in voltage, and trapping/recombination process. [Copyright &y& Elsevier]

Persistent storage symptoms after medication with alpha blocker decrease quality of life (QoL) and may disturb sexual activity. Therefore, we evaluated the effect of add on therapy with mirabegron in patient with benign prostatic hyperplasia (BPH) and persistent storage symptoms after treatment with tamsulosin. [Extracted from the article]