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Elucidation of the interplay between viruses and host cells is crucial for taming viruses to benefit human health. Cancer therapy using adenovirus, called oncolytic virotherapy, is a promising treatment option but is not robust in all patients. In addition, inefficient replication of human adenovirus in mouse hampered the development of an

Phenacoccus solani Ferris, 1918 and Vryburgia distincta (De Lotto, 1964) are herein reported occurring on succulent plants (Echeveria spp.) in South Korea. Both species have not been documented from South Korea except for quarantine inspection reports. In this study, diagnoses, descriptions, and photographs of the two species are provided with general information about their host plants and distributions.

In order to reduce the amount of excess silicon and carbon, reaction-bonded silicon carbide was fabricated by liquid silicon infiltration using a porous carbon preform prepared by chemical vapor deposition. A carbon preform was fabricated at 1100−1400 ℃ at 6.6 kPa for 1 h using acetylene. The deposited carbon preform has a porous structure with nano-sized carbon particles and uniform pore size distribution. Depending on the deposition temperature of the carbon preform, the porosity, the pore size, and the size of the carbon particles were controlled. As the deposition temperature increased, the porosity and average pore size increased, but the average carbon particle size decreased. The residual silicon of the prepared reaction-bonded silicon carbide was 2.7 % when the porosity of the carbon preform deposited at 1100 °C was 51.1 %. The hardness increased up to 21.7 GPa as the amount of the residual silicon reduced.

With the increase in electrification, the demand for the functionality and features of electric vehicles (EVs) is increasing, and accordingly, the required weight of copper (Cu) is increasing. Additionally, Cu usage increase as the wiring/functions of autonomous vehicles (AVs) increase. Therefore, limited energy efficiency due to the high mass density of Cu electrical cables has become a challenging issue to be overcome. With this trend, carbon-metal core-shell wire is an attractive lightweight material. It remains a challenge to further improve the properties of previously reported carbon-metal core-shell wire. Here, we report CNTF-Cu-Gr wires obtained by introducing graphene into Cu electroplated on CNTFs. Electroplated Cu was coated with graphene via chemical vapor deposition, which also provided synergetic effects, enabling better thermal and electrical properties. These CNTF-Cu-Gr wires exhibit excellent overall performance in terms of mechanical, electrical, and thermal properties and are lightweight. We expect that these dual core-shell wires will be used in practical applications in the near future.

Introduction Endoscopically assisted malarplasty with a greenstick fracture is a method for preserving the body eminence and improving arch protrusion. However, this technique is inadequate when malar body reduction is required. To compensate for these limitations, we developed a new surgical technique using the endoscope to reduce body protrusion. Material and methods We enrolled 261 patients who visited our clinic for zygoma reduction from January 2017 to December 2018. Their mean age was 31 (range 17–63) years. After a scalp incision, an incomplete osteotomy was created from the most prominent portion of the zygoma body to the zygomaticomaxillary suture line. A complete osteotomy was performed on the arch. These osteotomies resulted in an L-shaped zygoma segment after tapping the bone with a mallet. Results Of the 261 patients who underwent our L-rotation technique, 242 also received a corticotomy. Of those patients, 15 underwent a different degree of zygoma reduction on both sides. A floating zygomatic segment occurred in four cases, although no further surgery was required. One patient's zygomatic segment dropped on one side, requiring rigid fixation through the intraoral approach. Most patients were satisfied and there were no specific complications. Conclusions Endoscopically assisted malarplasty using an L-rotation technique enables the protrusion of both the arch and body to be reduced. The zygoma reduction can be modified based on the location of the incomplete osteotomoy line and the number of corticotomies required.

This paper discusses the effect of AB2 (Ti(Cr, Fe)2) phase on the hydrogenation properties of a Ti–Fe–Cr alloy system. Five Ti–Fe–Cr based alloys were fabricated by varying the Cr content. The microstructural analysis results revealed that the fraction of the Ti(Cr, Fe)2 phase increased with the increasing Cr content. The first hydrogenation test results indicated that all the alloys could absorb a significant amount of hydrogen at room temperature (30 °C) without a separate activation process. This behavior improved when the Ti(Cr, Fe)2 phase existed in the AB phase; the kinetics of the first hydrogenation tended to increase with the fraction of Ti(Cr, Fe)2 phase. The enhancement in the first hydrogenation kinetics of the Ti–Fe–Cr based alloys was attributed to the synergetic effect of the interface between the AB and Ti(Cr, Fe)2 phases and the inherent fast hydrogenation of the Ti(Cr, Fe)2 phase. However, the total hydrogen storage capacity decreased when the fraction of Ti(Cr, Fe)2 phase increased.

Bumblebees (Bombus spp.) are important pollinators of agricultural crops and wild plants, especially tomato and sweet pepper species requiring large-sized and buzzing pollinators. The endoparasitic mite Locustacarus buchneri Stammer 1951 (Acari; Podapolipidae) was identified from commercial populations of the introduced European bumblebee Bombus terrestris. We report the genus and species of this mite for the first time in Koran fauna. Identification was based on morphological and molecular characteristics. Morphological details were illustrated and compared with those to the original description. We analyzed partial cytochrome oxidase I gene to understand the phylogenetic relationship and possible source of invention. The maximum likelihood tree and haplotype network revealed that the Korean population is closely related to Japanese population than European population. The ecological significance of this finding and possible consequences of the invasive species to the native species are discussed.

In the present study, a large-area hybrid gamma imaging system was designed by adopting coded aperture imaging on the basis of a large-area Compton camera to achieve high imaging performance throughout a broad energy range (100–2000 keV). The system consisting of a tungsten coded aperture mask and monolithic NaI(Tl) scintillation detectors was designed through a series of Geant4 Monte Carlo radiation transport simulations, in consideration of both imaging sensitivity and imaging resolution. Then, the performance of the system was predicted by Geant4 Monte Carlo simulations for point sources under various conditions. Our simulation results show that the system provides very high imaging sensitivity (i.e., low values for minimum detectable activity, MDA), thus allowing for imaging of low-activity sources at distances impossible with coded aperture imaging or Compton imaging alone. In addition, the imaging resolution of the system was found to be high (i.e., around 6°) over the broad energy range of 59.5–1330 keV.

Achieving a highly active cathode surface with extremely efficient electrocatalysts for oxygen reduction kinetics is a fundamental necessity for durable fuel cells. Developing such active materials into desirable nanostructures is crucial in the pursuit of electrocatalysis. A facile preparation of cobalt decorated nitrogen and sulfur co-doped carbon nanostructures (Co–NSC) with the added advantage of Zeolitic imidazolate frameworks (ZIF), ZIF 67@ZIF 8 is reported here. The as-prepared Co, N, S, co-doped carbon (Co–NSC) electrocatalyst comes under platinum group metal-free (PGM-free) catalysts which intends to replace the scarce and highly expensive commercial Pt catalysts. Facile preparation of the Co–NSC catalyst that is scalable, low cost and highly ORR active makes the material advantageous. Co–doping sulfur has dramatically enhanced the intrinsic catalytic activity of the catalyst, and the degree of variation in sulfurization greatly influences the overall catalytic property. Co–NSC 200 with high sulfur doping exhibit a positively shifted onset potential of 0.81 V, and a high yielding current density of 5.5 mA cm−2 at 20 mV s−1.

Summary Cesium lead triiodide (CsPbI3) presents a desirable band gap, does not require the use of mixed halides for Si tandem solar cells, and possesses relatively high thermal stability owing to its inorganic components. However, the power conversion efficiency (PCE) of CsPbI3 is lower than that of organic cation-based halide perovskites with identical band gaps. The main factors that govern the PCE of CsPbI3 are the surface morphology and defect passivation of its thin films on substrates. In this study, we used the sequential dripping of a methylammonium chloride (MACl) solution (SDMS) to obtain highly uniform and pinhole-minimized thin films by controlling the intermediate stages of the crystallization process, followed by surface passivation using octylammonium iodides in ambient air. SDMS accelerated the crystallization process of the CsPbI3 perovskite layer, resulting in the formation of a uniform and dense surface with few pinholes. Consequently, we fabricated CsPbI3 solar cells with excellent PCE (20.37%).

Zirconium has been used as an alloying element to mitigate the difficulty in the initial hydrogenation of pristine TiFe, a room-temperature hydrogen storage material. The addition of zirconium induces the formation of AB2-type ternary phases such as τ1 and τ3. In this study, these ternary phases were produced individually and their activation kinetics and hydrogen storage properties were assessed. Ultimately, both τ1 and τ3 can be activated at room temperature under hydrogen at a pressure of 3 MPa. The result validates the presumption that Zr-added TiFe is easily activated with the help of the Ti–Fe–Zr ternary phases. In addition, they can store 1.8–1.9 wt% of hydrogen, which proves their own use as a hydrogen storage material. The easy activation may be caused by the compositional inhomogeneity of mixed metal oxide at the alloy surface, as revealed by depth-profiling X-ray photoelectron spectroscopy; this provides new reaction pathways for hydrogenation.

Summary The quaternary chalcogenide halides of group IV and V elements have attracted much attention due to their interesting semiconducting properties as well as a suitable band gap for solar cells. Here, for the first time, we report on solar cells using tin-antimony sulfoiodide (Sn2SbS2I3). Sn2SbS2I3 solar cells were fabricated using a chemical single-step deposition process with a solution containing a SbCl3-thiourea complex and SnI2 with the configuration of TiO2 and poly[2,6-(4,4-bis(2-ethylhexyl)-4H-cyclopenta[2,1-b;3,4-b′]dithiophene)-alt-4,7-(2,1,3-enzothiadiazole)] as the electron- and hole-transporting layers, respectively. The best-performing cell exhibits a power conversion efficiency of 4.04% under the illumination of standard AM 1.5G conditions (100 mW cm−2). These unencapsulated cells exhibited good stabilities at 80% relative humidity, 85°C in air, and under illumination, respectively. These results provide guidelines for fabrication of lead-free heteroleptic perovskite solar cells by hosting divalent or combinations of monovalent and trivalent metal cations.

Despite significant improvements in the synthesis of nitrogen (N)-doped carbon nanotubes (CNTs) and their versatile applications, there has always been a large difficulty in controlling the bonding configuration of N atoms within CNTs. In the current work, we report an effective chemical strategy to synthesize single-walled carbon nanotubes (SWNTs) with 100% of quaternary N via a chlorosulfonic acid(CSA) treatment. In this process, the pyridinic and pyrrolic groups were selectively and completely removed while retaining the quaternary N atoms. The presence of 2.04 at. % of quaternary N atoms within SWNTs was directly identified from a single sharp peak in the N 1s spectra of XPS, and indirectly supported by the downshift of C 1s peak in XPS, the upshift of G'-band in Raman spectroscopy, and the decrease of the work function from 5.46 to 4.59 eV. The doping effect of the quaternary N atoms on the macroscopic properties of SWNT fibers was verified by a large increase in the electrical conductivity from 0.63 to 2.17 MS/m. In perspective, our chemical approach can now be applied to synthesize carbon materials with controlled N functionalities for different applications.

This article reports the hydrogenation properties of several Mg–Mg2Ni composite specimens with increasing Ni content: 4.4, 11.3 (eutectic), and 16.3 (in at%). Mg–Mg2Ni composites were prepared by means of induction melting, followed by simple mechanical chipping of the casts. The hydrogenation and dehydrogenation reaction kinetics were studied, and reaction mechanisms were described by means of solid-gas reaction modeling. Absorption and desorption properties were evidenced to be diffusion controlled, with hydrogen diffusion through hydrided/dehydrided phases being the rate limiting step in most cases (the migration of metal/hydride interface at a constant velocity being rate-limiting in only few of them). The kinetics study was supported by a thorough thermal analysis to provide in-depth insights of the decomposition reaction. Hence, thermogravimetry (TG) and pressurized differential scanning calorimeter (PDSC) were combined to investigate the dehydrogenation properties such as hydrogen gravimetric density, reaction onset temperature, enthalpy and activation energy as a function of Ni content. Structural analysis included X-ray diffraction (XRD), scanning and transmission electron microscopy (SEM, TEM) to discuss the structural stability and microstructural evolution as a function of cycles, notably during the activation procedure. Finally, cyclic performance was evaluated for 100 cycles, using a custom-made large-scale reactor to demonstrate scale-up feasibility.

Emerged market multinational corporations (EDMNCs) ‒ those based in emerged markets that have transitioned out of emerging economic status ‒ have received little research interest from the international business scholarship, despite their growing presence in the global market. EDMNCs face significant competitive pressure to leverage cross-border knowledge to innovate and leapfrog their middle-zone status between emerging and developed market multinational corporations. Analyzing 174 publicly listed South Korean MNCs and their outward foreign direct investment (OFDI), we find that an EDMNC’s OFDI into developed and emerging markets contributes unequally to its home-country innovation. We also elaborate on the moderating effect of industry peers’ OFDI into developed countries through crowding out and spillover effects. These findings have implications for the OFDI and innovation literature in general, and particularly for international business scholarship focusing on an under-investigated category of MNCs that are increasingly becoming successful in international competition.

This study was performed to demonstrate a No Observed Adverse Effect Level (NOAEL) for an aqueous extract of Gryllus bimaculatus. According to other studies, using dried material or extract with ethanol or methanol determined a NOAEL dose of 1000 mg/kg or 5000 mg/kg in rats. Therefore, the Gryllus bimaculatus groups were administered orally at doses of 0, 1000, 2000, and 3000 mg/kg for four weeks. Two-week recovery groups were administered at doses of 0, and 3000 mg/kg. During administration and recovery period, the animals were observed for clinical signs, change of body weight, food consumption, hematology, and clinical chemistry. Rats in each group were periodically sacrificed, and organs were weighed and examined histologically. No difference arose between any of the dosage groups and the control group in clinical signs, histopathological examination, hematology, or clinical chemistry. In conclusion, 3000 mg/kg is a NOAEL dose for Gryllus bimaculatus extracts in Sprague Dawley rats.

Summary: Objective: Kissing stent (KS) technique has been used as an alternative to aortic bifurcated bypass surgery (ABBS) for aortoiliac occlusive disease (AIOD). We aimed to compare the results of ABBS and KS in AIOD. Methods: Medical records of patients treated with ABBS and KS between March 2011 and December 2016 in a single center were retrospectively analyzed. The patients' characteristics and clinical outcomes were evaluated. Results: Patients who underwent ABBS had a more common history of smoking (P = 0.04) and lower body mass index (P = 0.02). A significant difference was observed between the two groups in terms of the TransAtlantic Inter-Society Consensus II classification (P

Understanding the dielectric breakdown voltage of coatings inside plasma equipment is important for improving the reliability of semiconductor processes. Measurements of breakdown voltage can vary owing to many factors, but the measurement itself has not yet been studied systematically. In this paper, we designed two type tools to measure the breakdown voltage. We decided to use a one-electrode method with a 20 mm 2 electrode and chose to apply the voltage at 15 V/s to minimise measurement error. We used these tools to systematically evaluate the breakdown voltages of different coatings deposited using various methods. Coatings deposited using suspension plasma spraying had a higher breakdown voltage than coatings deposited using atmospheric plasma spraying, because suspension plasma spraying films can be deposited at high density, minimizing electrical stress. As the fluorine content in the coating increased, it is widely used for material of excellent etching resistance in fluorine plasma etching. However, dielectric breakdown voltage decreased with increasing fluorine content, which could affect process reliability.

Mechanochemical synthesis of CeB6 nanopowder was performed using a mixture of CeCl3, CeO2, B2O3 and either Mg or MgH2. The reaction for the CeO2-3B2O3-11MgH2 mixture to form CeB6 and MgO gradually proceeds during ball milling, while the mechanically induced self-propagating reaction (MSR) behavior is observed during ball milling of the CeO2-3B2O3-11 Mg mixture. X-ray diffraction patterns of the CeO2-3B2O3-11MgH2 mixture indicate that CeH2+x exists as an intermediate phase during the reaction. Scanning electron microscopy indicates that the particle size of CeB6 powder from the CeO2-3B2O3-11MgH2 mixture is much smaller than that from the CeO2-3B2O3-11 Mg mixture. Transmission electron microscopy revealed that CeB6 particles 10–30 nm in size from the CeO2-3B2O3-11MgH2 mixture are highly agglomerated with surface oxide layers. The mechanochemical reaction of the 2CeCl3-6B2O3-21MgH2 mixture produces CeB6 instead of Ce(BH4)3.

Thermal conductivity of carbon fibers (CFs) is an important property because CFs are used as heat dissipation fillers in composites for aerospace and electronics applications. However, evaluating thermal conductivity of a single filament of CFs is an arduous task due to dimensional issue of specimens and limitations of conventional measurement system. Therefore, we suggest an opto-thermal technique using Raman spectroscopy to measure thermal conductivity of commercial polyacrylonitrile based CFs (T300, T700SC and T800 H). The opto-thermal technique used that G band from Raman spectroscopy of carbon materials is shifted depending on temperature. For verifying an accuracy of the technique, the laser absorbance of CFs were estimated, and the thermal conductivity was measured depending on the length of CF. The measured data were reflected in the thermal conductivity calculation formula. It was demonstrated that the method provides more reasonable thermal conductivity values compare to a conventional Angstrom method. In addition, this simple technique confirmed that graphitic structure of CFs played a critical role in their thermal conductivity.

Hexagonally-arranged porous carbon films (HaPCFs) were prepared by proton beam irradiation and carbonization of hexagonally-arranged porous polystyrene films (HaPPSFs). HaPPSFs prepared by an improved phase separation method were irradiated with 150-keV proton beam at a fluence of 4 × 1016 ions cm−2 to enhance the thermal stability for high-temperature carbonization. Proton beam irradiation of HaPPSFs was found to induce crosslinking and surface oxidation reactions. The proton beam-irradiated HaPPSFs were carbonized at 800 °C under an inert atmosphere, resulting in the formation of HaPCFs. The prepared HaPCFs were found to have pseudo-graphitic structures containing both ordered and disordered graphitic structures. The prepared HaPCFs showed a good electrical conductivity.

In the aim of evidencing the relationship between Mg2FeH6 synthesis and the size of Fe particles, several specimens have been prepared by applying various milling energies (milling time) on a 2.1 Mg and 1Fe powder mixture doped with a small fraction of Unsaturated Fatty Amine (UFA). The resulting nano-crystalline composite structures display a broad Fe particle size distribution as a function of milling time. The hydrogenation of those complex powders has been conducted at temperatures lower than 400 °C under 60 bar of hydrogen pressure. As expected, the Fe particle size significantly influenced the hydrogenation kinetics. Also, the inevitable distribution of a minor fraction of oxides occurring during the milling process affected greatly the hydrogen storage capacity. Under the low pressure and temperature conditions selected in the frame of this study, lower than 100 bar and 500 °C conventionally used for synthesis of high purity Mg2FeH6, the hydrogenation reaction was demonstrated to be almost completed within 6 h, confirming the fast hydrogen absorption capability of the prepared materials. Plus, nearly 84 wt% of Mg2FeH6 was achieved under the afore mentioned moderate conditions and a minor fraction of unreacted Fe still remained due to diffusion constraints existing at low temperatures.