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The aim of this study was to explore the treatment effects of two surgical procedures, performed with nasal endoscopy, on treating adenoidal hypertrophy in children. A total of 100 children diagnosed with adenoidal hypertrophy were treated with curettage combined with microwave thermocoagulation and with low-temperature plasma radiofrequency ablation under nasal endoscopic guidance; 6 months after surgery, the effects on snoring, nasal congestion, hearing loss, and gland residue were retrospectively analyzed. Differences in snoring and hearing loss between the two groups were not statistically significant (P > 0.05), but the differences in nasal congestion and gland residue between the two groups were statistically significant (P < 0.05); the therapeutic effect was superior in the low-temperature plasma radiofrequency ablation group than in the curettage combined with microwave thermocoagulation group. Low-temperature plasma radiofrequency ablation with nasal endoscopy can achieve a better comprehensive effect on treating adenoidal hypertrophy in children than curettage combined with microwave thermocoagulation. [ABSTRACT FROM AUTHOR]

Highlights • Nonpolar InN films were grown by RF plasma-assisted evaporation technique. • The nonpolar InN films with uniform and smooth morphologies can be obtained. • New approach provides a low-cost route and have been rarely reported for the growth of InN films. Abstract Nonpolar InN nanocrystal films were grown by RF plasma-assisted evaporation technique on bare Si and quartz substrates, simultaneously. The as-grown InN films were characterized by X-ray diffraction, scanning electron microscopy, and Raman spectroscopy. The synergistic cooperation among the evaporation temperature, chamber pressure and substrate temperature is critical for the formation of nonpolar InN films. The absence of the (0 0 2) peak in the X-ray diffraction patterns indicates that as-grown InN films grew preferentially along the nonpolar plane. In addition, the InN films grown on Si and quartz substrates exhibit different crystallinity, morphology and stress. The In-rich growth condition can be responsible for the formation of nonpolar InN films. [ABSTRACT FROM AUTHOR]

The surface properties of poly-3-hydroxybutyrate (P3HB) membranes were modified using oxygen and an ammonia radio-frequency (RF, 13.56 MHz) plasma. The plasma treatment procedures used in the study only affected the surface properties, including surface topography, without inducing any significant changes in the crystalline structure of the polymer, with the exception being a power level of 250 W. The wettability of the modified P3HB surfaces was significantly increased after the plasma treatment, irrespective of the treatment procedure used. It was revealed that both surface chemistry and surface roughness changes caused by the plasma treatment affected surface wettability. A treatment-induced surface aging effect was observed and resulted in an increase in the water contact angle and a decrease in the surface free energy. However, the difference in the water contact angle between the polymers that had been treated for 4 weeks and the untreated polymer surfaces was still significant. A dependence between cell adhesion and proliferation and the polar component of the surface energy was revealed. The increase in the polar component after the ammonia plasma modification significantly increased cell adhesion and proliferation on biodegradable polymer surfaces compared to the untreated P3HB and the P3HB modified using an oxygen plasma. [ABSTRACT FROM AUTHOR]

Yttria stabilized zirconia thin films have been deposited by RF plasma enhanced MOCVD technique on silicon substrates at substrate temperature of 400 °C. Plasma of precursor vapors of (2,7,7-trimethyl-3,5-octanedionate) yttrium (known as Y(tod) 3 ), (2,7,7-trimethyl-3,5-octanedionate) zirconium (known as Zr(tod) 4 ), oxygen and argon gases is used for deposition. To the best of our knowledge, plasma assisted MOCVD of YSZ films using octanediaonate precursors have not been reported in the literature so far. The deposited films have been characterized by GIXRD, FTIR, XPS, FESEM, AFM, XANES, EXAFS, EDAX and spectroscopic ellipsometry. Thickness of the films has been measured by stylus profilometer while tribological property measurement has been done to study mechanical behavior of the coatings. Characterization by different techniques indicates that properties of the films are dependent on the yttria content as well as on the structure of the films. [ABSTRACT FROM AUTHOR]

Titanium nitrides have good tribo-mechanical and biomedical properties. They are employed to harden and protect cutting and sliding surfaces for industrial purpose and as a non-toxic outer-surface for bio-medical applications. In this study, pure titanium was nitrided using RF plasma technique. The microstructural, mechanical, tribological, electrochemical and biomedical properties of nitrided titanium were investigated. The X-ray diffraction demonstrates the formation of ε-Ti 2 N and the cubic δ-TiN phases after plasma nitriding. The microhardness of the nitride samples increases as the plasma-processing power increases up to 1300 HV 0.1 . That represents approximately 7-fold increment in the microhardness in comparison with the untreated titanium. High nitriding rate of 0.17 μm 2 /s was recorded for the sample that was treated at 650 W. The wear and corrosion resistance are improved after plasma nitriding. Moreover, the friction coefficient is reduced from nearly 0.75 for the untreated titanium to 0.25 for the nitride one. An enhancement in the biocompatibility of the nitrided titanium has been achieved. The number of grown mesenchymal stem cells was higher for nitrided substrates compared to that of the untreated titanium. The improved tribo-mechanical and electrochemical performance of the nitrided titanium can be attributed to the formation of super-hard titanium nitrided phases. [ABSTRACT FROM AUTHOR]

A set of discharges performed with the JET ITER-like wall is investigated with respect to control capabilities on tungsten sources and transport. In attached divertor regimes, increasing fueling by gas puff results in higher divertor recycling ion flux, lower divertor tungsten source, higher ELM frequency and lower core plasma radiation, dominated by tungsten ions. Both pedestal flushing by ELMs and divertor screening (including redeposition) are possibly responsible. For specific scenarios, kicks in plasma vertical position can be employed to increase the ELM frequency, which results in slightly lower core radiation. The application of ion cyclotron radio frequency heating at the very center of the plasma is efficient to increase the core electron temperature gradient and flatten electron density profile, resulting in a significantly lower central tungsten peaking. Beryllium evaporation in the main chamber did not reduce the local divertor tungsten source whereas core radiation was reduced by approximately 50%. [ABSTRACT FROM AUTHOR]

Surface modification of polylactic acid (PLLA) by plasma of radio-frequency magnetron discharge with hydroxyapatite target sputtering was investigated. Increased biocompatibility was demonstrated using studies with bone marrow multipotent mesenchymal stromal cells. Atomic force microscopy demonstrates that the plasma treatment modifies the surface morphology of PLLA to produce rougher surface. Infrared spectroscopy and X-ray diffraction revealed that changes in the surface morphology are caused by the processes of PLLA crystallization. Fluorescent X-ray spectroscopy showed that the plasma treatment also changes the chemical composition of PLLA, enriching it with ions of the sputtered target: calcium, phosphorus and oxygen. It is hypothesized that these surface modifications increase biocompatibility of PLLA without increasing toxicity. [ABSTRACT FROM AUTHOR]

Plasma polymerization of aniline is carried out by means of continuous RF and pulsed DC glow discharge plasma in a common reactor at different applied powers. The discharge control variables are optimized for good quality film growth and the role of fragmentation of the molecular structure on the structural, optical, morphological and optophysical properties of the deposited plasma polymerized aniline (PPAni) layers is investigated. Retention of the conjugated structure is found to be prominent at optimum applied power to the plasma in both the continuous RF and pulsed DC polymerization techniques. Improvement in conjugated structure and chain length have been observed in both the continuous RF and pulse DC PPAni thin films with the increase in applied power to the plasma up to a certain limit of applied power when working pressure is fixed at 0.15 mbar. A decrease in optical bandgap with the increase in applied power to the plasma is observed in both the pulsed DC and RF PPAni thin films, but it is more significant in case of RF PPAni films. The plasma polymerized aniline thin films are found to emit photoluminescence due to band to band transition and defects generated in the structure. [ABSTRACT FROM AUTHOR]

Abstract: We report the robust technique allowing manufacturing of superhydrophobic and oleophobic (omniphobic) surfaces with industrial grade low density polyethylene. The reported process includes two stages: (1) hot embossing of polyethylene with micro-scaled steel gauzes; (2) treatment of embossed surfaces with cold radiofrequency plasma of tetrafluoromethane. The reported surfaces demonstrate not only pronounced superhydrophobicity but also superoleophobicity. Superoleophobicity results from the hierarchical nano-scaled topography of fluorinated polyethylene surface. The observed superoleophobicity is strengthened by the hydrophobic recovery. The stability of the Cassie wetting regime was studied. [Copyright &y& Elsevier]