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Purpose - This paper finds the repurchase intentions of customers in a sharing economy via Airbnb and Uber, which are classic sharing-economy service businesses. Design/methodology - This paper analyzes sharing economy effects using variables in a structural equation model. Findings - We verified that values have a significant effect on the trust in a platform. We also verified that the effects that value propositions have on repurchase intention are significant. Research Limitations/Implications - First, there may be some distinction between men and women with regard to divided trust. Second, if commitment is divided into commitment to the host and commitment to the platform, as is the case for trust, the results will not be as expected. Third, if results could be categorized by nationality after gathering more samples, each nationality might have different opinions about these factors. Finally, the sharing economy can be identified and analyzed for various industries, such as space, transportation, and service. At this point, it is inconvenient to not have more implications. Originality/value - This study focuses on the repurchase intentions of customers. Unlike earlier studies, it is meaningful that trust is divided between the host and the platform, and that it can be analyzed. It is also important to establish the relationship between trust and commitment, and the relationship toward repurchasing in the shared-economy.

The interpretation of radiation dose is an important procedure for both radiological operators and persons who are exposed to background or artificial radiations. Dicentric chromosome assay (DCA) is one of the representative methods of dose estimation that discriminates the aberration in chromosomes modified by radiation. Despite the DCA-based automated radiation dose estimation methods proposed in previous studies, there are still limitations to the accuracy of dose estimation. In this study, a DCA-based automated dose estimation system using deep learning methods is proposed. The system is comprised of three stages. In the first stage, a classifier based on a deep learning technique is used for filtering the chromosome images that are not appropriate for use in distinguishing the chromosome; 99% filtering accuracy was achieved with 2,040 test images. In the second stage, the dicentric rate is evaluated by counting and identifying chromosomes based on the Feature Pyramid Network, which is one of the object detection algorithms based on deep learning architecture. The accuracies of the neural networks for counting and identifying chromosomes were estimated at over 97% and 90%, respectively. In the third stage, dose estimation is conducted using the dicentric rate and the dose-response curve. The accuracies of the system were estimated using two independent samples; absorbed doses ranging from 1- 4 Gy agreed well within a 99% confidential interval showing highest accuracy compared to those in previous studies. The goal of this study was to provide insights towards achieving complete automation of the radiation dose estimation, especially in the event of a large-scale radiation exposure incident.

Recently, logistics platforms that facilitate interaction and the exchange and transaction of information have quickly emerged in the Korean domestic market. In order to further advance the development of logistics platforms into green logistics platforms in which participation in the early stages is not active, appropriate checks and balances are needed so that service providers, users, and platform operators can grow together in green logistics platforms. The purpose of this study is to empirically verify the factors affecting participants’ intentions to use green logistics platforms. Out of the 230 questionnaires distributed from 25 June to 11 July 2019, 14 were excluded from analyses due to unsatisfactory responses, while 216 responses were used for statistical processing. The structural equation model (SEM) was used to test hypotheses in this research. The results showed that the network effect and security factors influenced perceived usefulness, and trust did not affect perceived usefulness. Perceived usefulness also significantly influenced the intention to use green logistics platforms. The results of this study present strategies and directions for the future development of green logistics platforms.

Carbon nanotube (CNT) films are fabricated on indium tin oxide (ITO) glass substrates by combining electrophoresis with photolithography using ribonucleic acid (RNA)–CNT hybrids as functionalized CNTs and their emission properties are investigated. The CNTs are well-dispersed by wrapping them with RNA and well-defined RNA–CNT patterns are obtained on the ITO glass substrate. The RNA–CNT films show good field emission properties, such as high current densities, low turn-on fields, and uniform emission images. The RNA–CNT hybrids compare favorably to other functionalized CNTs for use in the electrophoretic deposition.

Objectives/Hypothesis: It is known that arginase may be a regulator of diverse pathways, including production of nitric oxide (NO). Increased expression of arginase has been reported in several inflammatory lung diseases, including allergic asthma, suggesting that this may be a common feature underlying the pathophysiology of airway hyperreactivity. Thus, arginase I and II may play a role in the pathogenesis of allergic rhinitis. The distribution pattern and level of expression of arginase I and II were therefore determined in normal and allergic nasal mucosa. Study Design: Controlled, prospective study. Methods: The distribution pattern and level of expression of arginase I and II in normal and allergic nasal mucosa were evaluated using RT-PCR, immunohistochemistry, and Western blotting. Results: The level of expression of arginase I and II mRNA was increased in allergic nasal mucosa in comparison with normal nasal mucosa. In normal nasal mucosa, arginase I and II were expressed in the surface epithelium, submucosal glands, vascular endothelium, and fibroblasts. In allergic nasal mucosa, both enzymes were also localized to similar sites, in addition to inflammatory cells, and the level of expression were greatly increased compared with normal nasal mucosa. These findings were verified by Western blotting. Conclusions: These results indicate that arginase I and II may play a role in the pathophysiology of allergic rhinitis, and suggest the possible role of the L-arginine metabolic pathway through modulation of L-arginine availability as a substrate for nitric oxide synthase (NOS) and arginase in the pathogenesis of allergic rhinitis.

Photosensitive carbon nanotube (CNT) paste was prepared by 3-roll milling of multi-walled carbon nanotubes (MWNTs), UV-sensitive binder solution, and Ag as filler additives. Arrays of MWNT dots with a diode structure were fabricated by a combination of screen printing method and photolithography using these paste, and acetone utilized as the developer. The MWNT dots were well-defined and the organic binder materials in the dots were partially removed. The MWNT film without a heat treatment showed a high current density of 1.35 mA/cm 2 at 3.25 V/μm and low turn-on field of 2.2 V/μm at 100 μA/cm 2 . Acetone can be used as an efficient developer to form patterns and to remove the organic residues in patterns, simultaneously.

Multi-walled carbon nanotubes (MWCNTs) are shown to disperse in water, and be functionalized using RNA so that MWCNT/RNA hybrids can be fabricated on substrates by spray method. The material has strong adhesion on glass substrates or metal wires. A liquid elastomer surface treatment is used to make the field emitter tips protrude from the cathode. Possible methods of realizing field emitter sources, including X-ray sources, are discussed. The MWCNT/RNA hybrids have a higher emission current density and more uniform emission image than the MWCNTs on their own, since the RNA coated MWCNTs attach more strongly to the substrate. A diode configuration field emission X-ray source using the MWCNT/RNA hybrids on tungsten wire tip was tested and found to provide clear X-ray images.

This study examined the hypothesis that the control of NADPH oxidase-2 (Nox2)-mediated reactive oxygen species (ROS) regulates the expression of matrix metalloproteinases (MMPs) and the migration of macrophages. Lipopolysaccharide (LPS) stimulation of Raw264.7 cells and mice peritoneal macrophages increased the expression of MMP-9, 10, 12 and 13 mRNA, and also increased Raw264.7 cell migration. Treatment with an antioxidant (N-acetyl cysteine) or Nox inhibitors strongly inhibited the expression of MMPs by LPS and inhibited cell migration. LPS caused ROS production in macrophages and increased the mRNA expression of Nox isoforms Nox1 and Nox2 by 20-fold and two-fold, respectively. While Nox1 small interfering RNA (siRNA) did not inhibit LPS-mediated expression of MMPs, Nox2 siRNA inhibited the expressions of MMP-9, 10 and 12. Neither Nox1 nor Nox2 siRNA influenced the LPS-mediated expression of MMP-13. In addition, NAC or apocynin attenuated LPS-induced ROS production and MMP-9 expression. MMP-9 expression and cell migration were controlled by ERK1/2-ROS signaling. Collectively, these results suggest that LPS stimulates ROS production via ERK and induce various types of MMPs expression and cell migration.

Bright-field transmission electron microscopy (TEM) images, high-resolution TEM (HRTEM) images, and fast-Fourier transformed electron-diffraction patterns showed that n-butyl terminated Si nanoparticles were aggregated. The formation of Si1−xCx nanocomposites was mixed with Si nanoparticles and C atoms embedded in a SiO2 layer due to the diffusion of C atoms from n-butyl termination shells into aggregated Si nanoparticles. Atomic force microscopy (AFM) images showed that the Si1−xCx nanocomposites mixed with Si nanoparticles and C atoms existed in almost all regions of the SiO2 layer. The formation mechanism of Si nanoparticles and the transformation mechanism of n-butyl terminated Si nanoparticles embedded into Si1−xCx nanocomposites mixed with Si nanoparticles and C atoms are described on the basis of the TEM, HRTEM, and AFM results. These results can help to improve the understanding of the formation mechanism of Si nanoparticles.

This study demonstrated differential gene expression profiles in salicylate ototoxicity with oligonucleotide microarray. This study may also provide basic information on candidate genes associated with hearing loss and/or tinnitus or recovery after salicylate-induced cochlear dysfunction.Salicylate ototoxicity is accompanied by temporary hearing loss and tinnitus. The purpose of the present study was to evaluate the gene expression profiles in the mouse cochlea with salicylate ototoxicity using DNA microarray.The subject mice were injected intraperitoneally with 400 mg/kg of sodium salicylate; an approximate 30 dB threshold shift that was observed by auditory brainstem response was achieved 3 h after an injection of sodium salicylate and the hearing threshold returned to within normal range at 3 days. Differential gene expression profiles at 3 h after salicylate injection in comparison to the normal cochlea were analyzed with DNA microarray technology.No ultrastructural changes in the mice cochlea were observed by TEM at 3 h after salicylate injection. Microarray revealed that 87 genes were up-regulated twofold or more in the mouse cochlea with salicylate ototoxicity in comparison to the normal cochlea. Among these genes, increased expression levels of 30 functional genes were confirmed by semi-quantitative RT-PCR.

In this paper, We presents experimental results that demonstrate the pH sensing capability of MW-CNTs. High-density, well-aligned carbon nanotubes, which are MW-CNTs and vertically aligned on a large area of substrate, has been synthesized. The absorption of different range of pH buffer solution in the MW-CNTs changes the conductivity of the MW-CNTs at room temperature. A MEMS-based fabrication process was developed to fabricate a device where MWCNTs based sensing material was precisely assembled pattern.

Gas sensors for NO 2 detection were fabricated using printed multiwalled carbon nanotubes (MWCNTs) before and after electric field surface treatment. Printed MWCNTs showed an increase of sensitivity upon exposure to NO 2 and field emission due to vertical alignment and protrusion of CNTs from surface layer after electric field surface treatment. Electron field emission plays a role recovery when exposed to gas molecules in CNT. A Fast recovery time of the printed MWCNT gas sensor was obtained by ohmic heat with a partial field emission effect at room temperature.

Multiwall carbon nanotube (MWNT) films grown by thermal chemical vapor deposition on a micromachined substrate with a chrome heater and a diaphragm have been investigated as sensing materials of resistive gas sensors for nitrogen dioxide (NO 2 ). We fabricated the aligned MWNT films, which grew into mesh and serpentine shapes by photolithography. Photolithography patterned the cobalt catalyst layer. MWNT films showed a p-type electrical resistivity with decreasing electrical resistance upon exposure to NO 2 . The sensor exhibited a reversible response at a thermal treatment temperature of 130 °C for a time constant of a few minutes. The resistance change to NO 2 of the mesh-shaped MWNT films was found to be larger than that of the serpentine-shaped MWNT films.

A heating process for obtaining free-standing carbon nanotube emitters is presented with the aim of improving field-emission properties from the screen-printed multiwalled carbon nanotube (MWCNT) films. Using an atmosphere with an optimum combination of nitrogen and air for heat treatment of CNT films, the CNT emitters can be made to protrude from the surface. This allows for a high emission current and the formation of very uniform emission sites without special surface treatment. The morphological change of the CNT film by this technique has eliminated additional processing steps, such as surface treatment which may result in secondary contamination and damage to the film. Despite its simplicity the process provides a high reproducibility in emission current density which makes the films suitable for practical applications.

The micro-gas sensor based on carbon nanotubes (CNTs) was fabricated and its gas sensing characteristics on nitrogen dioxide () have been investigated. The sensor consists of a heater, an insulating layer, a pair of contact electrodes, and CNT-sensing film on a micromachined diaphragm. The heater plays a role in the temperature change to modify sensor operation. Gas sensor responses of CNT-film to at room temperature are reported. The sensor exhibits a reversible response with a time constant of a few minutes at thermal treatment temperature of .

This paper presents heating process for obtaining standing carbon nanotube emitters to improve field‐emission properties from the screen‐printed multiwalled carbon nanotube (MWCNT) films. In an atmosphere with optimum combination of nitrogen and air for heat treatment of CNT films, the CNT emitters can be made to protrude from the surface. This allows for high emission current and the formation of very uniform emission sites without special surface treatment. The morphological change of the CNT film by this technique has eliminated additional processing steps, such as surface treatment which may result in secondary contamination and damage to the film. Despite its simplicity the process provides high reproducibility in emission current density which makes the films suitable for practical applications.

The effect of improvement on the surface morphology of screen‐printed carbon nanotube (CNT) films was studied by using the optically clear poly‐dimethylsiloxane (PDMS) elastomer for surface treatment. After the PDMS activation treatment was applied to the diode‐type CNT cathode, the entangled carbon nanotube (CNT) bundles were broken up into individual free standing nanotubes to remarkably improve the field‐emission characteristics over the as‐deposited CNT film. Also, the cathode film morphology of a top gated triode‐type structure can be treated by using the proposed surface treatment technique, which is a low‐cost process, simple process. The relative uniform emission image showed high brightness with a high anode current. This result shows the possibility of using this technique for surface treatment of large‐size field emission displays (FEDs) in the future.

The effects of annealing on the optical and the electronics properties of ZnO thin films grown on p-Si(1 0 0) substrates by using radio frequency magnetron sputtering were investigated by X-ray diffraction (XRD), transmission electron microscopy (TEM), photoluminescence (PL), and X-ray photoelectron spectroscopy (XPS) measurements. The XRD patterns and pole figures showed that the crystallinity of the ZnO films grown on p-Si(1 0 0) substrates was improved by thermal treatment. XRD patterns, pole figures, and TEM images showed that the as-grown and the annealed ZnO films grown on Si(1 0 0) substrates had a c -axis preferential orientation in the [0 0 0 1] crystal direction. The PL spectra showed that luminescence peaks related to the free excitons and the deep levels appeared after annealing. The XPS spectra showed that the peak positions corresponding to the O 1s and the Zn 2p shifted slightly after thermal treatment. These results can help improve understanding of thermal effects on the optical and the electronic properties of ZnO thin films grown on p-Si(1 0 0) substrates.

By applying a critical field treatment instead of the conventional surface treatments such as soft rubber roller, ion beam irradiation, adhesive taping, and laser irradiation, electron emission properties of screen‐printed carbon nanotubes (CNTs) were enhanced and investigated based on the emission current‐voltage characteristics through scanning electron microscopy. After nanotube emitters were activated at the applied electric‐field of 2.5 V/um, the electron emission current density with good uniform emission sites reached the value of 2.13 mA/cm2, which is 400 times higher than that of the untreated sample, and the turn‐on voltage decreased markedly from 700 to 460 V. In addition, enhancement of the alignment of CNTs to the vertical direction was observed.

The CNTs-based sensors have received considerable attention because of their outstanding properties, such as faster response, higher sensitivity, and lower operating temperature. And we expect that CNTs-based electrochemical sensors offer substantial improvements in the performance of pH sensing device. This letter reports experimental results that demonstrate the pH sensing capability of the multiwalled carbon nanotubes (MWCNTs) film by using the thermal chemical vapor deposition (thermal CVD). It was found that electronic properties of MWCNTs can be changed by the introduction of different pH value solutions. The absorption of the hydroxide in pH buffer solution changes conductivity of the MWCNTs. We observed in situ measurement of electrical conductivity by cycling solution range from acid to base.

The film morphology of screen-printed carbon nanotube emitters was modified by using the liquid phase method, which used ethanol. This liquid treatment modified the surface morphology of the cathode because the organic binder is soluble in ethanol and it removed organic binder from the film. The field emission image uniformity and emission current density were improved without a heat treatment. This technique has showed that the ethanol treatment without the heat treatment provided an ease way to enhanced field emission by surface treatment.

To investigate emission properties of the photosensitive carbon nanotube emitters using ethanol as developer, a photosensitive carbon nanotube paste was formulated. for patterning of carbon nanotube paste, backside exposure and development process were carried out after screen printing and drying process. Ethanol is not only formed pattern but also removed organic vehicles in the photosensitive carbon nanotube film. The emission properties of patterned carbon nanotube film with and without firing were evaluated.

We fabricated a carbon nanotube (CNT)-based triode field emission flat lamp with a gated emitter structure, which is composed of a metal grid with a spacer as a gate, a cathode electrode layer, and a CNT layer. The metal mesh was designed with trenches and numerous holes to make a gap between gate and cathode electrodes and to provide electrons with a highly efficient passage. We observed that this metal mesh decreased the vibration and leakage current owing to high electric field generated from anode. As a result, the uniformity and stability of this field emission lamp was improved

We address a multiwall carbon nanotube (MWCNT) gas sensor that has an enhanced reproducibility. The sensor consists of a heater, an insulating layer, a pair of contact electrodes, and an MWCNT-sensing film on a micromachined diaphragm. The heater plays a role in the temperature changes to modify the rates for desorption of gases on the sensing surface during sensor operation. Gas sensor responses of MWCNT-film to NO/sub 2/ at room temperature are reported. We show that the sensor exhibits a reversible response with a time constant of a few minutes at thermal treatment temperature of 130/spl deg/C.

Diluted magnetic semiconductor (DMS) materials, which can utilize both the spin and charge properties of carriers, have attracted attention because the combination of two degrees of freedom holds promise for potential applications in spintronic devices [1, 2]. Among the various DMS materials, Ga1−x Mnx As and In1−x Mnx As DMS thin films grown on GaAs substrates have been the most extensively studied [3–6]. However, until now, the highest ferromagnetic transition temperature (Tc) obtained from III–V Ga1−x Mnx As DMS thin films has been 110 K [7]; thus, various studies on increasing the Tc of DMS materials have driven considerable efforts with the aim of realizing spintronic devices operating at higher temperature. Among several candidate DMS materials with a high Tc, (Zn1−x Cox )O DMSs are of current interest because they are theoretically expected to have high Tc values, as a consequence of the large energy gap and effective mass of (Zn1−x Cox )O [8, 9]. Since there are inherent problems due to possible existence of excess Co and CoO, the direct formation of (Zn1−x Cox )O films is very difficult. Thus, an alternative growth method of the (Zn1−x Cox )O films necessary for improving the crystallinity of films, and the improvement of the crystallinity of the films is very important in enhancing the value of Tc. Even though few works concerning the formation and the magnetic properties of the (Zn1−x Cox )O films on sapphire substrates were performed [10, 11], studies on the formation and the magnetic properties of the (Zn1−x Cox )O films on Si substrates have not been performed yet. Since Si substrates with large areas and good qualities are relatively cheap and extensively available in comparison with sapphires, Si technologies offer the potential applications for fabricating spintronic devices. This letter reports the effects of thermal annealing on the structural and optical properties of ZnO–Co digital alloys grown on p-Si (100) substrates by using the radio-frequency magnetron sputtering method. X-ray diffraction (XRD) measurement were performed to investigate the crystallization of the as-grown and the annealed ZnO–Co digital alloys, and superconducting quantum interference device (SQUID)

Background Adiponectin, one of the adipokines, has been implicated in the inflammatory process in patients with allergic rhinitis. The level of adiponectin is affected by immunotherapy. Considering the fact that adiponectin receptors (AdipoRs) mediate intracellular signaling events in response to the binding of adiponectin, the role of AdipoRs in healthy and allergic nasal mucosa should be determined. This study investigates the level of expression and distribution pattern of AdipoR1 and AdipoR2 in healthy, mild, and moderate/severe persistent allergic nasal mucosa to understand the role of adiponectin in allergic rhinitis. Methods The level of expression and distribution pattern of AdipoR1 and AdipoR2 were evaluated in healthy, mild, and moderate/severe persistent allergic nasal mucosa, using semiquantitative reverse-transcriptase–polymerase chain reaction (RT-PCR), immunohistochemistry, and Western blot analysis. Results AdipoR1 was expressed in healthy, mild, and moderate/severe persistent allergic nasal mucosa where it was commonly localized to the vascular endothelium. However, AdipoR2 was not expressed in any samples of nasal mucosa tested in the present study. Semiquantitative RT-PCR and Western blot analysis showed that the level of expression of AdipoR1 mRNA and protein was decreased in mild and moderate/severe persistent allergic nasal mucosa in comparison with healthy nasal mucosa, but not significantly different between mild and moderate/severe persistent allergic nasal mucosa. Conclusion These results indicate that AdipoR1 may play an important role in the pathogenesis of allergic nasal mucosa, suggesting a role for AdipoR1 in vascular dysfunction in mild and moderate/severe persistent allergic nasal mucosa.

The aim of this study was to investigate the clinical efficacy of single-staged modified uvulopalatopharyngoplasty (UPPP) with nasal surgery and the relationship between its surgical outcomes and an anatomy-based staging system in patients with obstructive sleep apnea syndrome (OSAS) with nasal obstruction.Before-after analysis at a university hospital.A total of 41 consecutive OSAS patients (mean age 40.1 ± 7.3 years) who underwent single-staged modified (uvula-preserving) UPPP with nasal surgery were included. The investigators compared subjective symptoms and polysomnographic data before and after surgery and investigated objective surgical outcomes according to the anatomy-based (Friedman) staging system and postoperative complications. Surgical success was defined as a reduction of at least 50% in preoperative apnea-hypopnea index (AHI) and a postoperative AHI of less than 20 per hour.After simultaneous nasal-oropharyngeal surgery, the AHI significantly decreased (from 45.9 ± 23.4 to 20.9 ± 22.1 events per hour; P.001) and the overall success rate was 56.1% (23/41). Surgical success rates in stages I, II, and III were 70.6% (12/17), 60.0% (9/15), and 22.2% (2/9), respectively. There were no major complications during or after surgery, and most minor complications were transient and resolved without morbidity.Single-staged modified UPPP with nasal surgery is an available and relatively safe surgical approach in OSAS patients with nasal obstruction. To achieve the best possible surgical outcomes, it is important to select appropriate patients using the anatomy-based staging system.