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This study aimed to determine the predictors of disease progression after functional endoscopic sinus surgery in patients with chronic rhinosinusitis.
A total of 281 adult chronic rhinosinusitis patients who underwent primary bilateral functional endoscopic sinus surgery between 2007 and 2017 and had at least 12 months of follow-up endoscopic evaluation were examined. Patients were divided into eosinophilic (n = 205) and non-eosinophilic chronic rhinosinusitis groups (n = 76). In order to determine adverse factors, post-operative endoscopic appearance scores were analysed in relation to the pre- and intra-operative findings using multiple regression analyses.
The post-operative course of eosinophilic cases deteriorated over time, like the early period for non-eosinophilic cases. Frontal sinus polyps recurred early in eosinophilic chronic rhinosinusitis. Multivariate analyses indicated young adulthood, asthma, high computed tomography score and frontal sinus polyps as significant adverse predictors.
Early, appropriate estimation of sinonasal conditions appears to be crucial for successful surgical management of chronic rhinosinusitis.
We study the interaction of relativistic jets with their environment, using 3-dimen- sional relativistic particle-in-cell simulations for two cases of jet composition: (i) electron-proton (e− − p+) and (ii) electron-positron (e±) plasmas containing helical magnetic fields. We have performed simulations of “global” jets containing helical magnetic fields in order to examine how helical magnetic fields affect kinetic instabilities such as the Weibel instability, the kinetic Kelvin-Helmholtz instability and the Mushroom instability. We have found that these kinetic instabilities are suppressed and new types of instabilities can grow. For the e− − p+ jet, a recollimation-like instability occurs and jet electrons are strongly perturbed, whereas for the e± jet, a recollimation-like instability occurs at early times followed by kinetic instability and the general structure is similar to a simulation without a helical magnetic field. We plan to perform further simulations using much larger systems to confirm these new findings.
Silver nanoparticle (AgNP) is one of the elegant material because its uses in various fields. In this study, AgNPs have been prepared by using Peltophorum pterocarpum (PP) flower extract as reducing and capping agent and aqueous silver nitrate (aq.AgNO3) as silver precursor. The synthesized nanoparticles were characterized using Ultra Violet - Visible (UV-Vis) spectroscopy, High Resolution Transmission Electron Microscope (HR-TEM) and Fourier Transform Infrared Spectroscopy (FT-IR), which reveals the formation of nanosized particles. The UV-Vis spectrum shows an absorption peak around 430nm. HR-TEM images of AgNPs with clear morphology and well dispersed prepared AgNPs.
In this paper, the authors have reported the structural and photoluminescence (PL) studies of pure and nickel (Ni) doped zinc oxide (ZnO) nanoparticles synthesized by the solution combustion method. The structural, morphological and optical studies are carried out by powder x-ray diffraction (XRD), field emission-scanning electron microscopy (FE-SEM) and PL spectra, respectively. The XRD pattern indicates that the prepared particles are in hexagonal wurtzite structure with the average crystalline size is around 35-50nm. Room temperature PL shows the near band edge related emission and the results are related several intrinsic defects in the ZnO nanoparticles.
In this paper, the effect of shock compression on the synthesis of a Bi-based oxide superconductor was investigated. Bi1.85-Pb0.35-Sr1.90-Ca2.05-Cu3.05-Ox calcined powder was shock-compacted around 20 GPa and 30 GPa, and divided specimens were annealed at 845 °C for 1, 6 and 48 hours. The specimens were evaluated by x-ray diffraction and scanning electron microscope.
ZnO nanorods were grown up from as-deposited ZnO film on which the zinc self-catalysts generated by a novel reducing method. Well aligned ZnO nanorods with a uniform high aspect ratio were grown up on multi-annealed samples. The length of nanorods depended significantly on the reaction time in the hydrothermal synthesis.
We investigated particle acceleration and shock structure associated with an unmagnetized
relativistic jet propagating into an unmagnetized plasma. Strong magnetic fields generated
in the trailing shock contribute to the electrons transverse deflection and acceleration.
We have calculated, self-consistently, the radiation from electrons accelerated in these
turbulent magnetic fields. We found that the synthetic spectra depend on the bulk Lorentz
factor of the jet, its temperature and strength of the generated magnetic fields. We have
also investigated accelerated electrons in strong magnetic fields generated by kinetic
shear (Kelvin-Helmholtz) instabilities. The calculated properties of the emerging
radiation will guide our understanding of the complex time evolution and/or spectral
structure in gamma-ray bursts, relativistic jets in general, and supernova remnants.
To increase X-ray photon number generated by laser-cluster interaction, it is important to understand the dependence of X-ray generation on cluster size. We carried out Xe K-shell X-ray generation using a conical nozzle with Xe clusters, the radius of which was controllable by adjusting the backing pressure. The experiment clarifies the result that the Xe K-shell X-ray photon number increases with increasing cluster radius from 8 to 12 nm, and saturates at the radius between 12 and 17 nm. We also investigated the Xe K-shell X-ray photon number dependence on laser intensity, and found that the threshold laser intensity of the Xe K-shell X-ray generation exists between 2 × 1017 and 5 × 1018 W/cm2.
The mechanism of improvement in gate oxide integrity (GOI) characteristics by H2 annealing in CZ-grown Silicon wafers was investigated. Grown-in defects that are considered to degrade GOI and which can be detected correlatively as 0.1 μm level size pits appearing after SC-1 cleaning, decrease drastically by H2 annealing, while other inert gases, i.e., N2 and Ar, do not exhibit such effect. Besides, H2 annealing shrinks or extinguishes oxygen precipitates significantly, while other gases do not. On the other hand, oxygen outdiffusion is exactly the same among H2, N2 and Ar annealing. From these results, it was concluded that the dominant mechanism for GOI characteristics improvement by H2 annealing is due to decomposition of the grown-in defects having Si-O bonding by the reduction reaction between Si-O bonding and hydrogen, and not due to a mere thermal decomposition enhanced by oxygen outdiffusion.
X-ray-excited luminescence of GaN doped with Eu ions as a luminescent center was observed in the wavelength range from 350 nm to 650 nm. Three peaks at 375 nm, 550 nm and 622 nm were found. To survey the mechanism of the photoluminescence due to non-resonance excitation, photoluminescence X-ray excitation spectra are also measured. The mechanism of the luminescence occurrence was briefly discussed based on the model developed by Emura et al.
Recent PIC simulations of relativistic electron-positron (electron-ion) jets injected into a stationary medium show that particle acceleration occurs in the shocked regions. Simulations show that the Weibel instability is responsible for generating and amplifying highly nonuniform, small-scale magnetic fields and for particle acceleration. These magnetic fields contribute to the electron's transverse deflection behind the shock. The “jitter” radiation from deflected electrons in turbulent magnetic fields has properties different from synchrotron radiation calculated in a uniform magnetic field. This jitter radiation may be important for understanding the complex time evolution and/or spectral structure of gamma-ray bursts, relativistic jets in general, and supernova remnants. In order to calculate radiation from first principles and go beyond the standard synchrotron model, we have used PIC simulations. We present synthetic spectra to compare with the spectra obtained from Fermi observations.
The effects of characteristics of the blocking layers in multilayered a-Si:H photoreceptors on electrophotographic properties are reported. The structure of the photoreceptor is Al/a-Si:H(p)/a-Si:H(i)/a-Si1−xCx. The thickness and boron doping ratio of the bottom p-type layer and the thickness and compositional fraction x of the surface a-Si1−xCx layer are varied. It is shown that the dark decay time is particularly sensitive to the thickness and doping ratio of the p-type layer. These dependences are discussed assuming a space charge layer in the p-type layer. It is also shown that the thickness and x of the a-Si1−xCx layer greatly influence the residual voltage and effective quantum efficiency of photocarrier generation.
GaAs was grown on Si substrate by metalorganic chemical vapor deposition using GaAs/GaAsP strained layer superlattice (SLS) intermediate layers. The dislocation density decreases at the interface between GaAs and SLS, but does not decrease in the SLS. When GaAs/GaAsP SLS is used as the intermediate layer, a part of the dislocation propagates into the top GaAs layer because of the lattice mismatch of GaAs and SLS. The low etch-pit-density of (3-5) x 105 cm−2 was obtained by using the intermediate layer of GaAs/GaAsP SLS and AlAs/GaAs superlattice with thermal-cycle annealing.
Deposition of SiNx films by ArF laser induced chemical vapor deposition has been investigated. The films exhibit excellent electrical properties; the high breakdown voltage and the low fixed charge are the same as in films deposited by LPCVD, but the BHF etching rate of them is larger by a factor about 4 than that prepared by the plasma CVD. The diffusion length of the radicals contributing to the deposition was estimated from the distribution of the deposition rate as a function of the deposition parameters. The optical emission from the radicals produced by ArF laser irradiation was also studied. Using these results, we discuss the mechanism of the deposition.
The deposition of W films by ArF laser-induced chemical-vapor deposition (LCVD) was investigated as a function of incident laser power, WF6 and H2 partial pressures, and substrate temperature. The deposition of W films by LCVD is discussed dividing that into two parts, thermal CVD (TCVD) and photon assisted CVD (PhCVD). The rate of PhCVD has been defined as the difference between the rates with and without laser irradiation. The reaction orders for PhCVD are 1, 0 with respect to WF6 and H2 partial pressures, respectively, and the rate linearly increases with increase in laser repetition rate. The activation energy in PhCVD is 0.17 eV. These facts indicate that, in LCVD, PhCVD takes place independently of TCVD and that the deposition rate in PhCVD is determined by the formation of F radicals in the dissociation of WF6 molecules by laser irradiation.
MOS capacitors with LCVD-W gates were fabricated and their characteristics were compared with those with sputtered-W gates. It was shown that the level of contamination due to mobile ions in the capacitor with the LCVD-W gate was extremely low.
Defects in thermal oxides were investigated by a photoluminescence technique. Thermal oxides with a thickness of 100 nm grown either by dry or wet oxidation were studied. A broad PL band at 2-4 eV was observed for both dry and wet oxides. Effects of annealing under vacuum or in atmospheres of Ar or N2 on the PL were also examined. The PL intensity was enhanced for the case of wet oxide by vacuum annealing at 700 °C. High-temperature anneal above 750 °C without O2 further generated PL centers for both dry and wet oxides. The formation mechanism of the PL centers will be discussed in terms of the decomposition of oxide at Si/SiO2 interface.
A new type of Pb(Mgl1/3Nb2/3)O3 (PMN) based thin film decoupling capacitor for high speed digital circuits is presented. The thin film capacitor fabricated on a ceramic Al2O3 substrate with Ball Grid Array (BGA) terminations showed low impedance and low inductance characteristics in the 100MHz – 1GHz range. The sol-gel derived Pb(Mg1/3Nb2/3)O3-PbTiO3(PMN-PT) thin film showed a high dielectric constant (k=3000) with broad temperature dependence. The capacitor consists of a PMN-PT thin film (0.8 µm thickness), Au electrodes, and solder balls mounted on the upper electrode as terminals. Numerical simulations based on the Partial Element Equivalent Circuit (PEEC) model were conducted for the design of electrodes, which gives low inductance of the capacitor. It was shown that the thin film 1.2mm × 1.2mm capacitor mounted on a board exhibits high capacitance of 20 nF, low ESR of 100 mΩ, and low inductance of 135 pH. These values are in good agreement with the results of numerical simulations.
Recent PIC simulations of relativistic electron-positron (electron-ion) jets injected into a stationary medium show that particle acceleration occurs in the shocked regions. Simulations show that the Weibel instability is responsible for generating and amplifying highly nonuniform, small-scale magnetic fields and for particle acceleration. These magnetic fields contribute to the electron's transverse deflection behind the shock. The “jitter” radiation from deflected electrons in turbulent magnetic fields has different properties from synchrotron radiation calculated in a uniform magnetic field. This jitter radiation may be important for understanding the complex time evolution and/or spectral structure of gamma-ray bursts, relativistic jets in general, and supernova remnants. In order to calculate radiation from first principles and go beyond the standard synchrotron model, we have used PIC simulations. We will present detailed spectra for conditions relevant to various astrophysical sites of collisionless shock formation. In particular we will discuss application to GRBs and SNRs.
We report an extremely rare case of congenital cholesteatoma of the mastoid region, presenting as acute mastoiditis. We also review the 16 previously reported cases of congenital cholesteatoma of the mastoid region.
A 65-year-old man presented with left-sided, post-auricular swelling and pain. Acute mastoiditis was diagnosed, with computed tomography demonstrating destruction of the bony plates of the posterior cranial fossa and sigmoid sinus. Initial surgery revealed a cholesteatoma in the mastoid, with no extension into the aditus ad antrum or attic. These findings were confirmed by pathological and immunohistochemical analysis of the surgical specimen, the latter using involucrin. The cholesteatoma matrix was completely removed in a second operation.
Including this case, only four of the 17 reported cases of congenital cholesteatoma of the mastoid region showed post-auricular pain or swelling, indicating acute mastoiditis. Clinicians should bear in mind that congenital cholesteatoma may be present in patients presenting with mastoiditis, particularly adults.
The wettability of Pb-free Sn-based solder over the Cu-based Cu60Zr30Ti10 bulk metallic glass surface was investigated. We observed that the as-polished surface was nonwetting for the solder, which was due to the surface oxide layer of ZrOx formed in air. After complete removal of the oxide layer, a thin layer of Ag was deposited on the clean Cu60Zr30Ti10 surface. The Ag-covered Cu60Zr30Ti10 surface showed relatively high resistivity to the reoxidation even in air, and thus the wettability of the Cu60Zr30Ti10 surface for the Sn-based solder was greatly improved.