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An extreme ultraviolet (EUV) lithography pellicle is used to physically protect a mask from contaminants during the EUV exposure process and needs to have a high EUV transmittance. The EUV pellicle should be fabricated using a freestanding thin film with several tens of nanometer thickness in an area of 110 × 142 mm 2 , which is a challenging task. Here, we propose a peel-off approach to directly detach the nanometer-thick graphite film (NGF)/Ni film from SiO 2 /Si wafer and significantly shorten the etching time of the Ni film. Combined with the residue-damage-free transfer method that used camphor as a supporting layer, we successfully fabricated a large-area (100 × 100 mm 2 ) NGF pellicle with a thickness of ∼20 nm, and an EUV transmittance of ∼87.2%., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

An extreme ultraviolet (EUV) pellicle consists of freestanding thin films on a frame; these films are tens of nanometers in thickness and can include Si, SiN X , or graphite. Nanometer-thick graphite films (NGFs), synthesized via chemical vapor deposition on a metal catalyst, are used as a pellicle material. The most common method to transfer NGFs onto a substrate or a frame is to use polymethyl methacrylate (PMMA) as a supporting layer. However, this PMMA-mediated technique involves several disadvantages in term of manufacturing NGF EUV pellicles. When removing the PMMA using acetone or O 2 plasma, defects or deflections can occur in the NGFs. Furthermore, PMMA residues are generally present on large-area NGFs. In this study, a transfer method using camphor instead of PMMA as the supporting layer was developed to overcome these problems. After the camphor/NGF was formed on the frame, camphor was removed via sublimation in an atmosphere of ethanol vapor. This study investigated the deposition and sublimation of camphor, and confirmed that no residue was present and no deflection or defects were observed in the NGFs. Thus, a large-area NGF pellicle was successfully fabricated using the camphor transfer process., (© 2021 IOP Publishing Ltd.)

EPOSS of polyhedral oligomeric silsesquioxanes (POSS) mixture structure and LPSQ of ladder-like polysilsesquioxane (LPSQ) structure were synthesized via sol-gel reaction. EPSQ had a high molecular weight due to polycondensation by potassium carbonate. The EPSQ film showed uniform surface morphology due to regular double-stranded structure. In contrast, the EPOSS-coated film showed nonuniform surface morphology due to strong aggregation. Due to the aggregation, the EPOSS film had shorter d-spacing (d1) than the EPSQ film in XRD analysis. In pencil hardness and nanoindentation analysis, EPSQ film showed higher hardness than the EPOSS film due to regular double-stranded structure. In addition, in the in-folding (r = 0.5 mm) and out-folding (r = 5 mm) tests, the EPSQ film did not crack unlike the EPOSS coated film.

Introduction: Human leukocyte antigen (HLA) identification at the allelic level is important for haematopoietic stem cell transplantation (HSCT). Next-generation sequencing (NGS) resolves ambiguous alleles by determining the phase of the polymorphisms. The aim of this study was to validate the software for HLA-SBT (sequence-based typing), assess Korean allele frequency, and characterise the performance of NGS-HLA typing., Methods: From the 2009 to 2016 registry, 1293 unrelated healthy donors with a complete dataset of previously characterised HLA-A, -B, -C, and -DRB1 loci were selected and assessed for frequency, haplotype inference, and relative linkage disequilibrium. For performance characteristics of NGS-HLA, alleles included in 1293 cases and ambiguous or alleles assigned as new by SBT-HLA software, or unassigned alleles were included. A total of 91 and 41 quality control samples resulted in 1056 alleles (132 samples × 4 loci × 2 diploid) for analysis. The GenDx NGSgo kit was used for NGS-HLA typing using the Illumina MiSeq platform., Results: A panel of 132 samples covered 231 alleles, including 53 HLA-A, 80 HLA-B, 43 HLA-C, and 55 HLA-DRB1 by HLA-SBT typing. Comparison of SBT-HLA and NGS-HLA typing showed 99.7% (1053/1056) concordance and discrepant cases were resolved by manual evaluation. Typing by NGS resulted in 67 HLA-A, 112 HLA-B, 71 HLA-C, and 72 HLA-DRB1 alleles. A total of 132 ambiguous, 4 new, and 1 unassigned alleles by HLA-SBT were resolved by NGS-HLA typing., Conclusions: NGS-HLA typing provided robust and conclusive results without ambiguities, and its implementation could support HSCT in clinical settings., (© 2020 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Surface hydrophobicity of anodic aluminum oxide (AAO) membranes was controlled via carbon coating using the CVD method or O 2 plasma treatment with insignificant changes of pore diameter. This study first demonstrated that a larger hydrophobic pore surface and hydrophilic membrane surface are favorable for developing high performance membranes., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

We report the role of chemically expanded graphite in the fabrication of high-performance graphene oxide fibers by wet spinning. X-ray diffraction peak showed that the interplanar distance of the expanded graphene oxide (EGO) fiber was more than that of graphene oxide (GO) fiber due to the expanded graphite. X-ray photon spectroscopy analysis revealed that EGO was more oxidized than GO. The hydrogen bonding network and secondary intermolecular interaction made the EGO aqueous solution more stable and crystalline, and it was able to be stretched in the coagulation bath. Morphological analysis showed the excellent alignment and compactness of EGO sheets in the fibers. The increased interplanar distance between the EGO sheets favored the edge-to-edge interaction more than the basal plane interaction within the fiber, thus resulting in high mechanical strength (492 MPa) and increased elongation (6.1%)., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Wearable technologies are driving current research efforts to self-powered electronics, for which novel high-performance materials such as graphene and low-cost fabrication processes are highly sought.The integration of high-quality graphene films obtained from scalable water processing approaches in emerging applications for flexible and wearable electronics is demonstrated. A novel method for the assembly of shear exfoliated graphene in water, comprising a direct transfer process assisted by evaporation of isopropyl alcohol is developed. It is shown that graphene films can be easily transferred to any target substrate such as paper, flexible polymeric sheets and fibers, glass, and Si substrates. By combining graphene as the electrode and poly(dimethylsiloxane) as the active layer, a flexible and semi-transparent triboelectric nanogenerator (TENG) is demonstrated for harvesting energy. The results constitute a new step toward the realization of energy harvesting devices that could be integrated with a wide range of wearable and flexible technologies, and opens new possibilities for the use of TENGs in many applications such as electronic skin and wearable electronics., (© 2018 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Atopic dermatitis (AD), a common childhood skin disorder, can limit a child's learning and physical activities. South Korean mothers, as primary caregivers, experience anxiety and helplessness when caring for their ill children. The aim of this study was to develop a hybrid AD education programme (consisting of a face-to-face session followed by 8 online sessions) and evaluate its effects on anxiety, caregiving efficacy and caregiving behaviour among mothers of children with AD. Twenty mothers of patients with AD treated in a South Korean hospital received one on-site session and 8 weekly online modules. After the intervention, mothers' mean±standard deviation anxiety reduced (from 50.3 ± 14.2 to 31.7 ± 6.3 points, t = 5.75, p < 0.001). Their caregiving efficacy and caregiving behaviour improved significantly, from 18.3 ± 3.5 to 29.4 ± 3.2 points (t = -9.64, p < 0.001) and from 47.7 ± 7.7 to 78.8 ± 4.9 points (t = -14.4, p < 0.001), respectively. The effects of the hybrid education programme for this population were significant. Healthcare providers should consider examining the programme nationwide, including in rural areas, while investigating its long-term effects.

Extreme ultraviolet lithography (EUVL) has received much attention in the semiconductor industry as a promising candidate to extend dimensional scaling beyond 10 nm. We present a new pellicle material, nanometer-thick graphite film (NGF), which shows an extreme ultraviolet (EUV) transmission of 92% at a thickness of 18 nm. The maximum temperature induced by laser irradiation (λ = 800 nm) of 9.9 W cm(-2) was 267 °C, due to the high thermal conductivity of the NGF. The freestanding NGF was found to be chemically stable during annealing at 500 °C in a hydrogen environment. A 50 × 50 mm large area freestanding NGF was fabricated using the wet and dry transfer (WaDT) method. The NGF can be used as an EUVL pellicle for the mass production of nanodevices beyond 10 nm.

Preventing reactive gas species such as oxygen or water is important to ensure the stability and durability of organic electronics. Although inorganic materials have been predominantly employed as the protective layers, their poor mechanical property has hindered the practical application to flexible electronics. The densely packed hexagonal lattice of carbon atoms in graphene does not allow the transmission of small gas molecules. In addition, its outstanding mechanical flexibility and optical transmittance are expected to be useful to overcome the current mechanical limit of the inorganic materials. In this paper, we reported the measurement of the water vapor transmission rate (WVTR) through the 6-layer 10 × 10 cm(2) large-area graphene films synthesized by chemical vapor deposition (CVD). The WVTR was measured to be as low as 10(-4) g/m(2)·day initially, and stabilized at ∼0.48 g/m(2)·day, which corresponds to 7 times reduction in WVTR compared to bare polymer substrates. We also showed that the graphene-passivated organic field-effect transistors (OFETs) exhibited excellent environmental stability as well as a prolonged lifetime even after 500 bending cycles with strain of 2.3%. We expect that our results would be a good reference showing the graphene's potential as gas barriers for organic electronics.

A facile and ultrafast method for geometry controllable and vertically transformative 3D graphene architectures is demonstrated. The 2D stacked graphene layers produced by exfoliation of graphite were transformed, e.g., from horizontal to vertical, by applying electric charge (-2 V with 1-3 μAh/cm2). The three-dimensionally transformed graphene layers have maximized surface area as well as high specific capacitance, 410 F g(-1) in LiClO4/PC electrolyte, which is 4.4 times higher than that of planar (stacked) graphene layers. Furthermore, they can remarkably exhibit 87% of retained capacitance as the scan rate is increased from 100 to 1000 mV s(-1), unlike planar graphene, which displays 61% retention under the same conditions.

A diode-pumped Q-switched neodymium-doped yttrium vanadate (Nd:YVO4, λ = 1064 nm) laser was applied to obtain graphene patterns on a photopolymer layer by direct ablation. In the transfer process of the graphene layer, the photopolymer was employed as a graphene supporting layer and it was not removed for the simplification of the process. The laser ablation was carried out on graphene/photopolymer double layers for various beam conditions. The results showed that the laser-ablated widths on the graphene/photopolymer double layer were much greater than those on the graphene monolayer, especially at lower scanning speeds and at higher repetition rates. The photopolymer layer was not removed by the laser ablation, and the thermal energy was considered to have been dissipated in the lateral direction of graphene instead of being conducted vertically to the glass substrate. The Raman spectrum results showed that the graphene layer was clearly removed on the laser-ablated region of interest.

The fabrication of interlayer dielectrics (ILDs) in flexible organic light-emitting diodes (OLEDs) not only requires flexible materials with a low dielectric constant, but also ones that possess the electrical, thermal, chemical, and mechanical properties required for optimal device performance. Porous polymer-silica hybrid materials were prepared to satisfy these requirements. Hollow SiO2 spheres were synthesized using atomic layer deposition (ALD) and a thermal calcination process. The hybrid film, which consists of hollow SiO2 spheres and polyimide, shows a low dielectric constant of 1.98 and excellent thermal stability up to 500 °C. After the bending test for 50 000 cycles, the porous hybrid film exhibits no degradation in its dielectric constant or leakage current. These results indicate that the hybrid film made up of hollow SiO2 spheres and polyimide (PI) is useful as a flexible insulator with a low dielectric constant and high thermal stability for flexible OLEDs.

Optical detection of graphene on a specific substrate is important for the analysis of the physical or chemical properties of graphene. Si3N4, an oxygen free substrate with high dielectric constant, is a good candidate to replace SiO2. In this letter, we report the optimization of the Si3N4 thickness for efficient optical characterization by means of the contrast, enhancement factor (F), and the Raman spectra of the graphene obtained on the selected Si3N4/Si substrate. The contrast (visibility) and enhancement factors (F, Raman intensity) of the graphene/Si3N4/Si structure were calculated as a function of the Si3N4 thickness and the wavelength of the excitation source. A suitable Si3N4 thickness generating high visibility and Raman intensities at the wavelength of the excitation source, 633 nm, was obtained.

Recently, graphene is gaining increasing popularity as one of the most functional materials for advanced electronic and optical devices owing to its high carrier mobility and optical transparency. Patterning the graphene calls for particular cares in line definition without carbon (C)-based residues that might be working as a leakage path. Thus, realization and processing of the graphene monolayer are very complicated and need to be stringently controlled. For this reason, in accordance, processing technology should be evolved with higher reliability and accuracy, and compatibility with the conventional unit processes including electron beam (e-beam) lithography, plasma etching, and nano-dimensional optical lithography. In this work, a reliable, simple, and cost-effective technique for patterning the graphene is proposed. Graphene film transferred on glass substrate is directly patterned by a quality factor (Q)-switched neodymium-doped yttrium vanadate (Nd:YVO4, λ = 1064 nm) pumped laser diode (LD). In order to optimize the process condition, various beaming conditions of repetition rate and scanning speed are experimented. From the optical microscope images, it has been shown that graphene film was more easily etched by direct laser patterning technique at higher repetition and faster scanning speed. It was confirmed by Raman spectrum where 2-dimensional (2-D) and graphite (G) peaks were closely investigated that graphene residue was also completely removed after the proposed processing technique.

Carbon nanotubes (CNTs) have great potential in the development of high-power electron beam sources. However, for such a high-performance electronic device, the electric and thermal contact problem between the metal and CNTs must be improved. Here, we report graphene as an interfacial layer between the metal and CNTs to improve the interfacial contact. The interfacial graphene layer results in a dramatic decrease of the electrical contact resistance by an order of 2 and an increase of the interfacial thermal conductivity by 16%. Such a high improvement in the electrical and thermal interface leads to superior field emission performance with a very low turn-on field of 1.49 V μm(-1) at 10 μA cm(-2) and a threshold field of 2.00 V μm(-1) at 10 mA cm(-2), as well as the maximum current of 16 mA (current density of 2300 A cm(-2)).

We report the formation mechanism of rutile TiO2 rods grown directly on fluorine doped tin oxide (FTO) glass by hydrothermal process at 130 degrees C. Through SEM images, we could monitor detailed nucleation and crystal growth process of TiO2 nanorods. The TiO2 nanorods started to nucleate and grow along the grain boundaries of SnO2 on FTO glass. As the reaction time increased, fine TiO2 nanorods started to encounter each other on (110) faces and merge, resulting in growth of micrometer scale rods in [001] direction. Through TEM, SAED, and XRD analyses, we propose that the nucleation of TiO2 on SnO2 grain boundaries occurs by Ostwald ripening (OR) while the merging of small TiO2 nanorods for the formation of larger rods occurs through oriented attachment (OA). The merged nanorods grow toward [001] direction to reduce surface energy.

Unintentionally formed nanocrystalline graphene (nc-G) can act as a useful seed for the large-area synthesis of a hexagonal boron nitride (h-BN) thin film with an atomically flat surface that is comparable to that of exfoliated single-crystal h-BN. A wafer-scale dielectric h-BN thin film was successfully synthesized on a bare sapphire substrate by assistance of nc-G, which prevented structural deformations in a chemical vapor deposition process. The growth mechanism of this nc-G-tailored h-BN thin film was systematically analyzed. This approach provides a novel method for preparing high-quality two-dimensional materials on a large surface., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A difference in work function plays a key role in charge transfer between two materials. Inorganic electrides provide a unique opportunity for electron transfer since interstitial anionic electrons result in a very low work function of 2.4-2.6 eV. Here we investigated charge transfer between two different types of electrides, [Ca(2)N](+)·e(-) and [Ca(24)Al(28)O(64)](4+)·4e(-), and single-walled carbon nanotubes (SWNTs) with a work function of 4.73-5.05 eV. [Ca(2)N](+) · e(-) with open 2-dimensional electron layers was more effective in donating electrons to SWNTs than closed cage structured [Ca(24)Al(28)O(64)](4+) · 4e(-) due to the higher electron concentration (1.3 × 10(22) cm(-3)) and mobility (∼ 200 cm(2) V(-1) s(-1) at RT). A non-covalent conjugation enhanced near-infrared fluorescence of SWNTs as high as 52%. The field emission current density of electride-SWNT-silver paste dramatically increased by a factor of 46,000 (14.8 mA cm(-2)) at 2 V μm(-1) (3.5 wt% [Ca(2)N](+) · e(-)) with a turn-on voltage of 0.85 V μm(-1).

We synthesized thermally stable graphene-covered Ge (Ge@G) nanowires and applied them in field emission devices. Vertically aligned Ge@G nanowires were prepared by sequential growth of the Ge nanowires and graphene shells in a single chamber. As a result of the thermal treatment experiments, Ge@G nanowires were much more stable than pure Ge nanowires, maintaining their shape at high temperatures up to 850 °C. In addition, field emission devices based on the Ge@G nanowires clearly exhibited enhanced thermal reliability. Moreover, field emission characteristics yielded the highest field enhancement factor (∼2298) yet reported for this type of device, and also had low turn-on voltage. Our proposed approach for the application of graphene as a protective layer for a semiconductor nanowire is an efficient way to enhance the thermal reliability of nanomaterials.

A highly stretchable hybrid nanogenerator has been developed using a micro-patterned piezoelectric polymer P(VDF-TrFE), PDMS-CNT composite, and graphene nanosheets. Mechanical and thermal energies are simultaneously harvested from a single cell of the device. The hybrid nanogenerator exhibits high robustness behavior even after 30% stretching and generates very stable piezoelectric and pyroelectric power outputs due to micro-pattern designing., (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Transparent conducting films (TCF) made up from carbon nanotubes (CNTs) have a tremendous potential in replacing the indium tin oxide films. Compare to single wall CNTs multiwall CNTs are more metallic and are more suitable candidate for the TCF. In this letter we report the use of selectively grown mm-scale, few-wall, vertically aligned CNTs for the fabrication of TCF. Water-assisted chemical vapor deposition was used to grow the mm-scale CNTs within short growth time. A special post-growth water-vapor treatment allowed us to remove the catalyst-free CNT forest very easily from the substrate and use it for the further process. A filtration-wet transfer process was used to form the TCF. The TCF shows sheet resistance of 228 omega/sq. at 72% transparency (at 550 nm). The ratio of optical conductivity to dc conductivity was observed in between 0.21 to 0.25 for below 80% transmission.

Thin graphene/polymer sheet composites were fabricated using easily soluble expanded graphite (ESEG), and their field emission (FE) parameters were examined. Due to the high dispersability of ESEG, a stable graphene suspension was prepared by ultrasonication in toluene without the need for a surfactant. The suspension consisted of exfoliated graphene sheets with a thickness of 1 - 2 nm. Using a calendering process, the solution was further shear mixed with ethyl cellulose to obtain a well-dispersed graphene/polymer composite. The composite was screen printed onto a conducing substrate to fabricate the FE cathode layers. The FE measurements were taken in a diode configuration at an applied electrostatic field and inter-electrode distance of 1.7 to 6 V/microm and approximately 200 microm, respectively. The threshold turn-on-field was approximately 3.5 V/microm at a current density of approximately 10 microA/cm2 with a corresponding mean field enhancement factor of 1350 +/- 50. Emission occurred mainly from the edges and bends of the graphene layers. The luminescence uniformity of the composite cathode layers was examined using a phosphor-coated anode.

Purpose: In this study an examination was done of the effects of the American Society of PeriAnesthesia Nurses (ASPAN) Evidence-Based Clinical Practice Guidelines on body temperature, shivering, thermal discomfort, and time to achieve normothermia in patients undergoing total knee replacement arthroplasty (TKRA) under spinal anesthesia., Methods: This study was an experimental study with a randomized controlled trial design. Participants (n=60) were patients who underwent TKRA between December 2011 and March 2012. Experimental group (n=30) received active and passive warming measures as described in the ASPAN's guidelines. Control group (n=30) received traditional care. Body temperature, shivering, thermal discomfort, time to achieve normothermia were measured in both groups at 30 minute intervals., Results: Experimental group had slightly higher body temperature compared to control group (p=.002). Thermal discomfort was higher in the experimental group before surgery but higher in the control group after surgery (p=.034). It decreased after surgery (p=.041) in both groups. Time to achieve normothermia was shorter in the experimental group (p=.010)., Conclusion: ASPAN's guidelines provide guidance on measuring patient body temperature at regular intervals and on individualized and differentiated hypothermia management which can be very useful in nursing care, particularly in protecting patient safety and improving quality of nursing.

Monodisperse yolk-shell SiO(2) -TiO(2) microspheres were synthesized using core-shell silica microspheres as templates. In the absence of prior surface modifications, a uniform coating of the TiO(2) layer on the core-shell silica was achieved through a sol-gel route. Mesoporous silica shells between the outer TiO(2) shell and the SiO(2) core were selectively removed by using a weak base, yielding yolk-shell SiO(2) -TiO(2) microspheres (ys-SiO(2) @TiO(2) ). Using the same templates, we synthesized Pt-encased microspheres (SiO(2) @Pt-TiO(2) ), in which Pt nanoparticles are embedded between the SiO(2) core and the TiO(2) shell. Selective etching of the silica shells in SiO(2) @Pt-TiO(2) yields Pt-encased yolk-shell SiO(2) -TiO(2) microspheres (ys-SiO(2) @< Pt >TiO(2) ), which contain void spaces suitable for use as nanoreactors. The ys-SiO(2) @< Pt >TiO(2) catalyst shows enhanced hydrogen production from water under UV-light irradiation presumably as a result of multiple reflections within the void spaces and can be reused without losing their activity. Moreover, this core-shell template method is effective for the synthesis of other yolk-shell microspheres with different metal oxides., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The intrinsic properties of initially p-type doped graphene (grown by chemical vapor deposition (CVD)) can be recovered by buffered oxide etch (BOE) treatment, and the dominant factor governing p-type doping is identified as the H(2)O/O(2) redox system. Semi-ionic C-F bonding prevents the reaction between the products of the H(2)O/O(2) redox system and graphene. BOE-treated graphene field effect transistors (FETs) subsequently exposed to air, became p-type doped due to recovery of the H(2)O/O(2) redox system. In comparison, poly(methyl methacrylate) (PMMA)-coated graphene FETs had improved stability for maintaining the intrinsic graphene electronic properties.

Purpose: The purpose of this study was to test whether pre-operative visual information and parental presence had positive effects on anxiety, delirium, and pain in pediatric patients who awoke from general anesthesia in a post-surgical stage., Methods: This study used a non equivalent control-group post test design (n=76). Independent variables were provision of pre-operative visual information and parental presence for post-surgical pediatric patients in PACU (post anesthesia care unit). Dependent variables were anxiety, delirium, and pain in the pediatric patients measured three times at 10 minute intervals after extubation in the PACU. Measurements included Numerical Rating Scale for assessing state anxiety, Pediatric Anesthesia Emergence Delirium Scale by Sikich & Lerman (2004) for delirium, and Objective Pain Scale by Broadman, Rice & Hannallah (1988) for pain., Results: Experimental group showed significantly decreased state anxiety at time points-10, 20, and 30 minutes after extubation. Delirium was significantly lower at 10 minutes and 30 minutes after extubation in the experimental group. Pain was significantly lower at 10 minutes after extubation in the experimental group., Conclusion: The results of this study suggest that this intervention can be a safe pre-operative nursing intervention for post-surgical pediatric patients at PACU.

Unlike graphene, the existence of bandgaps (1-2 eV) in the layered semiconductor molybdenum disulphide, combined with mobility enhancement by dielectric engineering, offers an attractive possibility of using single-layer molybdenum disulphide field-effect transistors in low-power switching devices. However, the complicated process of fabricating single-layer molybdenum disulphide with an additional high-k dielectric layer may significantly limit its compatibility with commercial fabrication. Here we show the first comprehensive investigation of process-friendly multilayer molybdenum disulphide field-effect transistors to demonstrate a compelling case for their applications in thin-film transistors. Our multilayer molybdenum disulphide field-effect transistors exhibited high mobilities (>100 cm(2) V(-1) s(-1)), near-ideal subthreshold swings (~70 mV per decade) and robust current saturation over a large voltage window. With simulations based on Shockley's long-channel transistor model and calculations of scattering mechanisms, these results provide potentially important implications in the fabrication of high-resolution large-area displays and further scientific investigation of various physical properties expected in other layered semiconductors.

The multi-stage effect has been revisited through growing carbon nanotube field emitters on single strand carbon fiber with a thickness of 11 µm. A prepared linear electron source exhibits a turn-on field as low as 0.4 V µm(-1) and an extremely high field enhancement factor of 19,300, when compared with those results from reference nanotube emitters grown on flat silicone wafer; 3.0 V µm(-1) and 2500, respectively. In addition, we introduce a novel method to grow nanotubes uniformly around the circumference of carbon fibers by using direct resistive heating on the continuously feeding carbon threads. These results open up not only a new path for synthesizing nanocomposites, but also offer an excellent linear electron source for special applications such as backlight units for liquid crystal displays and multi-array x-ray sources.

This paper reports a large scale production route for polystyrene (PS) nanoparticle-functionalized graphene sheets using water based in situ microemulsion polymerization. The higher surface area of the graphene basal plane and the better proximity of the reactant species in in situ microemulsion polymerization were used to functionalize the graphene sheets using PS nanoparticles. The thermal properties of the PS were improved with the incorporation of graphene in the composite. The modified graphene exhibited good compatibility and interactions with the host PS matrix to form conducting PS films., (Copyright 2010. Published by Elsevier Inc.)

We developed a novel biosensor comprising a transducer of carboxyl end-capped overoxidized polypyrrole nanowire electrode and a probe of tripeptide (Gly-Gly-His) selectively cognitive of Cu2+. The developed sensor was demonstrated to specifically detect Cu2+ in the nanomolar range. The diameter of the polypyrrole nanowires, prepared by one step template-free polymerization, was approximately 60-90 nm. For functionalization of the electrode, the carboxyl group was introduced by the addition of pyrrole-α-carboxylic acid which was covalently coupled with the amine group of the tripeptide. The structural features of the peptide functionalized nanowire electrode were confirmed by X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) spectroscopy. Using cyclic and square wave voltammetry, the nanowire biosensor proved to be highly sensitive to Cu2+ in the range of 20-300 nM., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Novel monoclinic CuO nanobundles, 0.8-1 microm in size, were synthesized at 130 degrees C in the presence of sodium dodecyl benzenesulfonate (SDBS) by a simple hydrothermal method. Each nanobundle was comprised of many nanorods with one ends growing together to form a center and another ends radiating laterally from this center. The length and the diameter of these assembled nanorods are in the range of 200-300 nm and about 20-30 nm, respectively. HRTEM and SAED results indicated that the CuO nanorods grow along the [010] direction. An investigation of the hydrothermal process revealed that the reaction time, temperature and surfactant play important roles in the formation of the resultant CuO nanostructures. Isolated CuO nanorods were obtained when the temperature was increased to 190 degrees C, and CuO microflowers composed of many nanosheets were produced at 130 degrees C when cetyltrimethylammonium bromide (CTAB) was employed instead of SDBS. The possible mechanism for the formation of these CuO nanostructures was discussed simply on the basis of the experimental results.

Large area of self-organized, free standing anodic titanium oxide (ATO) nanotube membranes with clean surfaces were facilely prepared to desired lengths via electrochemical anodization of highly pure Ti sheets in an ethylene glycol electrolyte, with a small amount of NH4F and H2O at 50 V, followed by self-detachment of the ATO membrane from the Ti substrate using recycling processes. In the first anodization step, the nanowire oxide layer existed over the well-arranged ATO nanotube. After sufficiently rinsing with water, the whole ATO layer was removed from the Ti sheet by high pressure N2 gas, and a well-patterned dimple layer with a thickness of about 30 nm existed on the Ti substrate. By using these naturally formed nano-scale pits as templates, in the second and third anodization process, highly ordered, vertically aligned, and free standing ATO membranes with the anodic aluminum oxide (AAO)-like clean surface were obtained. The inter-pore distance and diameter was 154 +/- 2 nm and 91+/- 2 nm, the tube arrays lengths for 25 and 46 hours were 44 and 70 microm, respectively. The present study demonstrates a simple approach to producing high quality, length controllable, large area TiO2 membrane.

Purpose: This study was done to examine effects of Nei-Guan acupressure on nausea, vomiting and level of satisfaction for gynecological surgery patients who were using a patient-controlled analgesia (PCA)., Methods: For this study, 51 patients were assigned to one of three groups, a control group (17 patients), experimental group 1 (finger acupressure group) (17 patients), and experimental group 2 (relief band group) (17 patients). The data were collected for 24 hr in the recovery room of a university hospital located in Seoul. The 6 hr-intervals including the time of leaving the recovery room were taken into consideration., Results: The occurrence of nausea between the experimental group with Nei-Guan acupressure treatment and the control group was different. However, there was no difference in nausea and vomiting control or level of patient satisfaction between the finger acupressure group and the relief band group., Conclusion: Nei-Guan acupressure is recommended for nursing practice as a way for alleviating the opioid-induced nausea and accelerating the recovery of patients who are using PCA after surgery.

Beta-In(2)S(3) nanotubes were synthesized using an organic solution pyrolysis route. The shape of the beta-In(2)S(3) nanotubes was controlled from hexagonal nanoplates to nanotubes simply by changing the reaction time. The growth mechanism of the nanotubes was explained by oriented attachment. The beta-In(2)S(3) nanotubes had a diameter, wall thickness and length of 5.0 nm, 0.79 nm and >10 microm, respectively. The diameter of the beta-In(2)S(3) nanotubes was found to be dependent on the sulfur concentration.

In this study, we developed a new drug delivery system using anodic oxidation. The growth of a porous oxide layer on aluminum under anodic bias in various electrolytes has been studied for more than 40 years. Anodic Aluminum Oxide (AAO) has many uniform nanopores on its surface. This nanoporous surface can be used for drug storage. The effects of the diameter and depth of the AAO on the release characteristics of a drug were investigated. Paclitaxel was used for the drug loading and release test. Paclitaxel was loaded on the inside of the AAO by ultrasonication. The amount of the drug released from the AAO was analyzed by high performance liquid chromatography (HPLC). The pore size did not affect the drug release behavior. However, the depth of the pores had a significant influence on the release rate of the drug.

A facile hydrothermal route has been developed for the synthesis of nearly spherical copper nanoparticles, copper nanocubes and ribbon-like network nanostructures. The as-prepared copper nanostructures were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), and UV-vis spectrum analysis. These copper products were fabricated in the presence of surfactant sodium dodecyl benzenesulfonate (SDBS) acting not only as stabilizer but also as size and shape controller via hydrothermal reduction process. HRTEM revealed that the surface of the copper nanostructures was packed with a thin layer of impurities such as oxide combined surfactant or amorphous surfactant. The influence of surfactant concentration and temperature on the resultant copper nanostructures was investigated in details. UV-vis spectra indicated that strong red shift existed for the copper ribbon-like network nanostructures due to the novel morphology as well as the presence of impurities on the surface.

In this work, using single walled carbon nanotubes (SWNTs) made by chemical vapor deposition (CVD) process, transparent conductive film (TCF) was prepared for mass production. The optimum dispersion condition and two step sprays coating of aqueous SWNTs solution and organic polymer solutions have enabled us to achieve the high conductivity, excellent flexibility, and strong adhesion. Through the analysis of particle size and zeta potential of dispersed SWNTs in water, it was found that the particle size and solution stability were reduced as dispersing time increased. Acid treatment of sprayed SWNTs layer removed the surfactant and provided a hole doping effect to SWNTs, resulting in significant reduction of the surface resistance of SWNTs film. Consequently, CVD SWNTs flexible transparent conductive film (surface resistance of 270 ohm/sq, transmittance of 82.3% at 550 nm with substrate effect, and of 93.5% without substrate effect) was developed.

There is some controversy regarding the effects of HNO3 on films of single-walled carbon nanotubes (SWCNTs). In this study we examined the change in sheet resistance of an HNO3-modified SWCNT film after different drying times at 85 degrees C using various analytical techniques. The shift and suppression in the Raman spectra, bleaching of the transition peaks related to van Hove singularities and a shift in the original peak in the C 1s XPS spectra provided evidence for p-type doping. A decrease in sheet resistance was also observed in the SWCNTs films due to the removal of residual N-methylpyrrolidone solvent on the surface and bundle of SWCNTs. These results suggest that p-type doping has a larger effect on the sheet resistance than the removal of residual N-methylpyrrolidone by an HNO3 treatment.

Easily soluble expanded graphite is synthesized in a one-step exfoliation process that can be used for the lowcost mass production of graphene for various applications because of the simplicity and speed of the process. The graphene obtained is sufficiently expanded to be dispersed in aqueous solutions with an ordinary surfactant and in organic solvents., (Copyright © 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim.)

The ternary I-III-VI(2) semiconductor of CuInSe(2) nanoparticles with controllable size was synthesized via a simple solvothermal method by the reaction of elemental selenium powder and CuCl as well as InCl(3) directly in the presence of anhydrous ethylenediamine as solvent. X-ray diffraction patterns and scanning electron microscopy characterization confirmed that CuInSe(2) nanoparticles with high purity were obtained at different temperatures by varying solvothermal time, and the optimal temperature for preparing CuInSe(2) nanoparticles was found to be between 180 and 220 degrees C. Indium selenide was detected as the intermediate state at the initial stage during the formation of pure ternary compound, and the formation of copper-related binary phase was completely deterred in that the more stable complex [Cu(C(2)H(8)N(2))(2)](+) was produced by the strong N-chelation of ethylenediamine with Cu(+). These CuInSe(2) nanoparticles possess a band gap of 1.05 eV calculated from UV-vis spectrum, and maybe can be applicable to the solar cell devices.

This paper reports the use of spin coatable Fe naphthenate (Fe(C(11)H(7)O(2))(2)) as an electron beam sensitive direct writable catalyst suitable for growing high quality carbon nanotubes (CNTs). Vertically aligned, densely packed, equal in height, three- to four-walled and 5-7 nm inner diameter CNTs were grown on the nanoscale stripe patterns by water-assisted chemical vapor deposition. The correlation between electron beam dosage and the growth characteristics of CNTs is also discussed.

The development of solution-processable, high-performance n-channel organic semiconductors is crucial to realizing low-cost, all-organic complementary circuits. Single-crystalline organic semiconductor nano/microwires (NWs/MWs) have great potential as active materials in solution-formed high-performance transistors. However, the technology to integrate these elements into functional networks with controlled alignment and density lags far behind their inorganic counterparts. Here, we report a solution-processing approach to achieve high-performance air-stable n-channel organic transistors (the field-effect mobility (mu) up to 0.24 cm(2)/Vs for MW networks) comprising high mobility, solution-synthesized single-crystalline organic semiconducting MWs (mu as high as 1.4 cm(2)/Vs for individual MWs) and a filtration-and-transfer (FAT) alignment method. The FAT method enables facile control over both alignment and density of MWs. Our approach presents a route toward solution-processed, high-performance organic transistors and could be used for directed assembly of various functional organic and inorganic NWs/MWs.

Purpose: This study examined the moderating and mediating effects of self-efficacy on the relationships between predictor variables (decisional balance and processes of change) and the outcome variable (stages of change) using the Transtheoretical Model., Design: Cross-sectional data were collected from 147 current and former smokers at three vocational technical high schools in Korean metropolitan areas., Methods: The survey instruments included decisional balance, self-efficacy, processes of change (behavioral and experiential), and stages of change. Regression analyses were used to identify the mediating effects of self-efficacy., Results: Self-efficacy mediated the relationships of decisional balance and behavioral processes with stages of change, but not that of experiential processes with stages of change., Conclusions: The study results will provide valuable information regarding how each predictor variable is connected and path through adoption of smoking cessation behavior. By understanding mechanisms of behavior change, health professionals could develop effective smoking cessation interventions with consideration of roles of self-efficacy in the smoking cessation behavior change. [Asian Nursing Research2009;3(1):15-23].

Conclusions: We recommend amoxacillin/clavulanate, cephalosporins and macrolides rather than penicillin as the first-line drug in chronic sinusitis with nasal polyps. In cases where there is no improvement of symptoms, cultures should be taken from the middle meatus, followed by appropriate selection of second-line antibiotics according to the sensitivity test results., Objective: To investigate the causative bacteria and the antimicrobial susceptibility in patients with chronic sinusitis and nasal polyps in Korea., Materials and Methods: The bacteriology and antimicrobial susceptibility of maxillary sinus aspirates from 81 patients were evaluated., Results: Aerobes were isolated from 58.0% of the cultures from the middle meatus and from 48.1% of those from the maxillary sinus. Staphylococcus aureus, Haemophilus influenzae, and Streptococcus pneumoniae were the most prevalent aerobic pathogens. Anaerobes were isolated from 8.6% of the cultures from the middle meatus and from 18.5% of the cultures from the maxillary sinus. The predominant anaerobic organisms were Prevotella and Peptostreptococcus in adults but none of them were cultured in children. A high rate of concordance of the middle meatus and maxillary sinus was noted. Monomicrobial infection was most commonly observed. Ampicillin-resistant H. influenzae isolates were cultured in 46% of the cases. Penicillin resistance rates were 93% for Staph. aureus; 25% of Strep. pneumoniae were intermediate and 25% were resistant.

15-lipoxygenase-1 (15-LO-1) is involved in the differentiation of human tracheobronchial epithelial cells. Here, we investigated the relation between 15-LO-1 expression and the differentiation of human nasal epithelium. In retinoic acid (RA)-sufficient culture media, 15-LO-1 expression in normal human nasal epithelial cell time-dependently increased, but its expression was undetectable in RA-deficient culture media. Moreover, in RA-deficient culture media, IL-4 at 1 ng/ml concentration time-dependently induced 15-LO-1 expression. In addition, MUC8 gene expression, a marker of mucociliary differentiation, was up-regulated by 15-LO-1, which was itself induced by IL-4. In murine nasal mucosa, the expression of leukocyte type-12-LO, a functional equivalent of 15-LO-1, reduced after postnatal day 7. Our findings suggest that 15-LO-1 is related to the differentiation of human nasal epithelium, and that it may mediate the mucociliary differentiation of human nasal epithelium.