The Effect of Time Spent on Online Gaming on Problematic Game Use in Male: Moderating Effects of Loneliness, Living Alone, and Household Size.

OBJECTIVE: This study aimed to investigate the association between gaming time and problematic game use (PGU) within a large sample of Korean male gamers and to examine the potential moderating effects of loneliness, living alone, and household size. METHODS: This study employed data from 743 male gamers from the National Mental Health Survey 2021, a nationally representative survey of mental illness conducted in South Korea. Self-reported data on the average gaming time per day, severity of PGU, loneliness, living alone, and household size were used. RESULTS: Gaming time was positively associated with PGU and this relationship was significantly moderated by loneliness such that the positive effect of gaming time on PGU was greater when the levels of loneliness were high. The three-way interaction effect of gaming time, loneliness, and living alone was also significant, in that the moderating effect of loneliness on the relationship between gaming time and PGU was significant only in the living alone group. However, household size (i.e., number of housemates) did not moderate the interaction between gaming time and loneliness among gamers living with housemates. CONCLUSION: These results suggest the importance of considering loneliness and living arrangements of male gamers, in addition to gaming time, in identifying and intervening with individuals at heightened risk of PGU.

Gut microbiota modulation and gold nanoparticle-mediated photothermal therapy for treatment of recalcitrant acne.

Recent studies highlight that gut dysbiosis, an imbalanced state of intestinal microbiota, exacerbates skin inflammation. Here, we showed the presence of gut microbiota alterations in two patients with recalcitrant acne and investigated the impact of its therapeutic modulation together with gold nanoshell-mediated photothermal therapy (gold PTT).

Black Si Photocathode with a Conformal and Amorphous MoSx Catalytic Layer Grown Using Atomic Layer Deposition for Photoelectrochemical Hydrogen Evolution.

We demonstrated how the photoelectrochemical (PEC) performance was enhanced by conformal deposition of an amorphous molybdenum sulfide (a-MoSx) thin film on a nanostructured surface of black Si using atomic layer deposition (ALD). The a-MoSx is found to predominantly consist of an octahedral structure (S-deficient metallic phase) that exhibits high electrocatalytic activity for the hydrogen evolution reaction with a Tafel slope of 41 mV/dec in an acid electrolyte. The a-MoSx has a smaller work function (4.0 eV) than that of crystalline 2H-MoS2 (4.5 eV), which induces larger energy band bending at the p-Si surface, thereby facilitating interface charge transfer. These features enabled us to achieve an outstanding kinetic overpotential of ∼0.2 V at 10 mA/cm2 and an onset potential of 0.27 V at 1 mA/cm2. Furthermore, the a-MoSx layer provides superior protection against corrosion of the Si surface, enabling long-term PEC operation of more than 50 h while maintaining 87% or more performance. This work highlights the remarkable advantages of the ALD a-MoSx layer and leads to a breakthrough in the architectural design of PEC cells to ensure both high performance and stability.

Reduction of Ethyl Carbamate in an Alcoholic Beverage by CRISPR/Cas9-Based Genome Editing of the Wild Yeast.

Ethyl carbamate (EC) is a naturally occurring substance in alcoholic beverages from the reaction of ethanol with urea during fermentation and storage. EC can cause dizziness and vomiting when consumed in small quantities and develop kidney cancer when consumed in excess. Thus, the reduction of EC formation in alcoholic beverages is important for food safety and human health. One of the strategies for reducing EC contents in alcoholic beverages is developing a new yeast starter strain to enable less formation of EC during fermentation. In this study, we isolated a polyploid wild-type yeast Saccharomyces cerevisiae strain from the Nuruk (Korean traditional grain-based inoculum of wild yeast and mold) and developed a starter culture by genome engineering to reduce EC contents in alcoholic beverages. We deleted multiple copies of the target genes involved in the EC formation in the S. cerevisiae by a CRISPR/Cas9-based genome editing tool. First, the CAR1 gene encoding for the arginase enzyme responsible for the formation of urea was completely deleted in the genome of S. cerevisiae. Additionally, the GZF3 gene encoding the transcription factor controlling expression levels of several genes (DUR1, 2, and DUR3) related to urea absorption and degradation was deleted in S. cerevisiae to further reduce the EC formation. The effects of gene deletion were validated by RT-qPCR to confirm changes in transcriptional levels of the EC-related genes. The resulting strain of S. cerevisiae carrying a double deletion of CAR1 and GZF3 genes successfully reduced the EC contents in the fermentation medium without significant changes in alcohol contents and fermentation profiles when compared to the wild-type strain. Finally, we brewed the Korean traditional rice wine Makgeolli using the double deletion strain of S. cerevisiae dCAR1&GZF3, resulting in a significant reduction of the EC content in Makgeolli up to 41.6% when compared to the wild-type strain. This study successfully demonstrated the development of a starter culture to reduce the EC formation in an alcoholic beverage by CRISPR/Cas9 genome editing of the wild yeast.

The Effect of a Non-Invasive Positive Pressure Ventilation Simulation Program on General Ward Nurses' Knowledge and Self-Efficacy.

The purpose of this study is to develop a simulation-based ventilator training program for general ward nurses and identify its effects. Quantitative data were collected from 29 nurses (intervention group: 15, control group: 14), of which seven were interviewed with focus groups to collect qualitative data. The quantitative results revealed significant differences in ventilator-related knowledge (p = 0.029) and self-efficacy (p = 0.026) between the intervention and control groups. Moreover, three themes were derived from meaningful statements in the qualitative data: understanding psychophysical discomfort of the patient while applying the ventilator; helping in ventilator care; and establishing a future ventilator training strategy. The findings confirmed that the non-invasive positive pressure ventilation (NPPV) simulation program is an effective method for improving the knowledge of ventilator nursing and self-efficacy and will be helpful in developing educational methods and strategies related to ventilator nursing for general ward nurses.

Safety of Combined Fractional Microneedle Radiofrequency and CO2 as an Early Intervention for Inflammatory Acne and Scarring Treated With Concomitant Isotretinoin.

BACKGROUND: Fractional microneedle radiofrequency (FMRF) systems are popular options for treating acne scars. However, treatment efficacy when used in combination with traditional ablative fractional laser (AFL) and the safety profile with concomitant use of isotretinoin remain unknown. OBJECTIVE: The aim of this study was to assess the safety and efficacy of an early intervention combination treatment protocol for inflammatory acne and acne scars. MATERIALS AND METHODS: The electronic records of 71 patients with inflammatory acne and acne scars were included in this retrospective observational study. Data were collected for all patients who received combination FMRF and AFL. Within the study group, 43 patients were receiving low-dose isotretinoin or had completed isotretinoin within the past 3 weeks. RESULTS: The mean Scar Global Assessment score significantly decreased after 3 sessions of combination treatment (n = 71). Patients with inflammatory acne showed a significant decrease in the number of inflammatory lesions (n = 30). Patients with concomitant low-dose isotretinoin use reported a further decrease in Scar Global Assessment score (n = 43). There were no reported persistent side effects, including prolonged inflammatory reaction or scarring. CONCLUSION: Combination treatment with FMRF and AFL is an effective and well-tolerated treatment modality for acne scars and inflammatory acne.

Bipolar Energetics and Bifunctional Catalytic Activity of a Nanocrystalline Ru Thin-Film Enable High-Performance Photoelectrochemical Water Reduction and Oxidation.

Photoelectrochemical (PEC) cells, which represent a promising technology for the production of hydrogen fuel through water splitting reactions, must meet two criteria to achieve high-performance operation: (i) a high thermodynamic open-circuit potential and (ii) a low kinetic overpotential. Herein, we achieved these criteria in both an oxygen-evolving n-Si photoanode and hydrogen-evolving p-Si photocathode by simple electrodeposition of a nanocrystalline thin film of Ru. The bifunctional electrocatalytic activity of the nanocrystalline Ru led to low overpotentials in both the acidic oxygen evolution reaction (0.27 V) and alkaline hydrogen evolution reaction (0.04 V). In addition, the nanocrystalline Ru/Si junctions influenced the interface energetics via the induction of an extrinsic electrochemical potential on the surface of the Ru nanocrystals through a redox reaction rather than the chemical potential of the electrons (work function) of bulk Ru. The nanocrystalline Ru film exhibited bipolar applicability, enabling both Ru/n-Si and Ru/p-Si junctions with high Voc values of 0.63 and 0.5 V, respectively. As a result, the n-Si photoanode in the acidic electrolyte and the p-Si photocathode in the alkaline electrolyte generated a photocurrent of 10 mA/cm2 at record values of 0.87 and 0.42 V versus the reversible hydrogen electrode, respectively. These results provide insight into the development of high-performance PEC cells based on a nanocrystalline electrocatalyst.

Effect of a topical antioxidant serum containing vitamin C, vitamin E, and ferulic acid after Q-switched 1064-nm Nd:YAG laser for treatment of environment-induced skin pigmentation.

BACKGROUND: Extrinsic skin aging caused by atmospheric pollutants is associated with a sustained inflammatory response which is a significant risk factor for lentigines and melasma. AIMS: The aim of this study was to evaluate the efficacy of topical application of combination formulation of vitamin C, vitamin E, and ferulic acid as an adjuvant to Q-switched Nd:YAG (QSNY) lasers treatment in individuals with lentigines and melasma. METHODS: A single blinded, prospective, randomized split-face trial was conducted. Eighteen men and women between 26 and 53 years old were treated with a combination antioxidant serum on one randomized side of their face immediately after QSNY laser and twice daily for 2 weeks. Patients were evaluated using digital photography and spectrometry to assess the melanin index and erythema index. Melasma severity score and global improvement scores also were assessed. RESULTS: The treated side of the face exhibited a significantly greater reduction in the melanin index. There was no significant difference in post-treatment erythema. More clinical improvement was observed on the treated side compared with the untreated side. CONCLUSIONS: Our study suggests that topical application of a combination vitamins C, E, and ferulic acid antioxidant formula may be effective as an adjuvant option in QSNY lasers.

Nitramine-Group-Containing Energetic Prepolymer: Synthesis, and Its Properties as a Binder for Propellant.

A composite solid propellant which generates high propulsive force in a short time is typically composed of an oxidizer, a metal fuel powder and a binder. Among these, the binder is an important component. The binder maintains the mechanical properties of propellant grains and endures several thermal and mechanical stresses in the engine. Several studies have been reported for the development of energetic propellant binders for increasing the propellant's propulsive force. While several materials have been studied for the synthesis of energetic prepolymers, a nitramine-group-containing prepolymer is a suitable candidate because these types of prepolymers are less toxic and more cost-effective when compared to the traditional glycidyl azide polymers (GAP) and triazole-based prepolymers. Considering the lack of studies for the binder using a nitramine-group-containing prepolymers, we synthesized a nitramine-group-containing monomer and polymerized a nitramine-group-containing prepolymer. The prepolymer was then used for the preparation of the binder and its thermal and mechanical properties, as well as the effect of the plasticizer, were studied. The binder that was prepared using the prepolymer containing a nitramine-group showed very high elongation, tensile strength. Nitrate-ester (NE)-type plasticizer could reduce the glassy transition temperature (Tg)of the binder successfully. Also, high-energy is released due to the decomposition of the nitramine-group at around 245 °C, thus exhibiting the efficiency of the nitramine-group-containing prepolymer as an excellent energetic binder material.

A semiconductor junction photoelectrochemical device without a depletion region.

Semiconductor junctions are believed to form a depletion region at the band edge of the semiconductor as the chemical potentials for electrons (work functions) are aligned to the same level. Here, we demonstrated that ultrathin Ni film (less than 4 nm thick)/Si junction-based photoelectrochemical (PEC) devices have no depletion region due to three distinct phenomena: (i) the electrostatic or electrochemical potential extrinsically charged to the electrolytic-capacitive Ni surface dominates rather than the chemical potential of electrons (work function) of the bulk Ni, (ii) the charged potential is dynamically variable depending on the reaction and is rapidly volatile so as not to be constant; therefore, (iii) the charged potential is misaligned with the chemical potential of Si under equivalent circuit conditions. Such junction PEC devices were shown to follow a novel operating principle in which the output voltage (open circuit potential) is generated by the electrochemical potential charged at the Ni surface, and not by the light-induced potential (photovoltage) in Si. In addition, due to the bipolar charging nature, the ultrathin Ni film was effective in achieving a high open circuit potential in both p-Si photocathodes (0.57 V) and n-Si photoanodes (0.45 V). These anomalous results were not explained by the classical Schottky diode model based on the equilibrium of diffusion-drift current but by establishing a new model based on the equilibrium of the diffusion-charging current without accounting for the depletion region. Our findings provide an explanation for the unexpected results of the nanostructured PEC devices and insight into a new design that can overcome conventional limitations.

Seasonal differences in dissolved organic matter properties and sources in an Arctic fjord: Implications for future conditions.

The Arctic Ocean is undergoing drastic changes due to the effects of climate change. Arctic fjords are preferred systems to study these changes as they respond quickly to variations in ocean, land and atmosphere conditions. In this study, we investigated for the first time the seasonal variability of dissolved organic matter (DOM) properties and its origin in an Arctic fjord, which allows for an assessment of the future potential effects of climate change in this environment. We conducted an integrated analysis of the concentrations, optical properties (absorption and fluorescence), and molecular size distributions of DOM in two seasons (October 2017 and April 2018) and in eight to ten stations in Kongsfjorden (Svalbard) along with the related environmental parameters such as chlorophyll-a, inorganic nutrients, particulate organic carbon (POC), temperature, and salinity. Our results showed that, in both seasons, the DOM in the fjord was predominately of autochthonous origin with a seasonally variable terrestrial input. The dissolved organic carbon (DOC) concentrations were consistently higher in October than in April at each station. Fluorescence spectroscopy revealed a marked seasonal variability depending on the DOM fluorophore types and size fractions. In October, humic-like and tryptophan-like substances were dominant whereas in April, tyrosine-like compounds represented, on average, 58% of the DOM fluorescence. This study points out the key role of spring sea ice melting in determining the DOM properties of the fjord in spring.

Seebeck-voltage-triggered self-biased photoelectrochemical water splitting using HfOx/SiOx bi-layer protected Si photocathodes.

The use of a photoelectrochemical device is an efficient method of converting solar energy into hydrogen fuel via water splitting reactions. One of the best photoelectrode materials is Si, which absorbs a broad wavelength range of incident light and produces a high photocurrent level (~44 mA·cm-2). However, the maximum photovoltage that can be generated in single-junction Si devices (~0.75 V) is much lower than the voltage required for a water splitting reaction (>1.6 V). In addition, the Si surface is electrochemically oxidized or reduced when it comes into direct contact with the aqueous electrolyte. Here, we propose the hybridization of the photoelectrochemical device with a thermoelectric device, where the Seebeck voltage generated by the thermal energy triggers the self-biased water splitting reaction without compromising the photocurrent level at 42 mA cm-2. In this hybrid device p-Si, where the surface is protected by HfOx/SiOx bilayers, is used as a photocathode. The HfOx exhibits high corrosion resistance and protection ability, thereby ensuring stability. On applying the Seebeck voltage, the tunneling barrier of HfOx is placed at a negligible energy level in the electron transfer from Si to the electrolyte, showing charge transfer kinetics independent of the HfOx thickness. These findings serve as a proof-of-concept of the stable and high-efficiency production of hydrogen fuel by the photoelectrochemical-thermoelectric hybrid devices.

Dynamic Photoelectrochemical Device with Open-Circuit Potential Insensitive to Thermodynamic Voltage Loss.

The open-circuit potential ( Voc) represents the maximum thermodynamic potential in a device, and achieving a high Voc is crucial for self-biased photoelectrochemical (PEC) devices that use only solar energy to produce chemical energy. In general, Voc is limited by the photovoltage ( Vph), which is a potential difference generated by light-induced thermodynamic processes at semiconductor photoelectrodes, such as the generation and recombination of charge carriers. Therefore, low light intensity and nanostructured semiconductor materials degrade Vph (and Voc) by inefficient carrier generation and by enhancing recombination loss, respectively. Here, we report that Voc in dynamic PEC devices employing a porous NiO x/Si photocathode is insensitive to thermodynamic losses, which was clarified by varying the carrier generation and recombination rates. The Voc values were observed to be unchanged even under a low light intensity of 0.1 sun, as well as for different morphologies such as nanostructured and polycrystalline Si. These findings shed light on the potential merit of dynamically operated PEC systems.

Hydrogen Water Drinking Exerts Antifatigue Effects in Chronic Forced Swimming Mice via Antioxidative and Anti-Inflammatory Activities.

PURPOSE: This study was performed to evaluate antifatigue effect of hydrogen water (HW) drinking in chronic forced exercise mice model. MATERIALS AND METHODS: Twelve-week-old C57BL6 female mice were divided into nonstressed normal control (NC) group and stressed group: (purified water/PW-treated group and HW-treated group). Stressed groups were supplied with PW and HW, respectively, ad libitum and forced to swim for the stress induction every day for 4 consecutive weeks. Gross antifatigue effects of HW were assessed by swimming endurance capacity (once weekly for 4 wk), metabolic activities, and immune-redox activities. Metabolic activities such as blood glucose, lactate, glycogen, blood urea nitrogen (BUN), and lactate dehydrogenase (LDH) as well as immune-redox activities such as reactive oxygen species (ROS), nitric oxide (NO), glutathione peroxidase (GPx), catalase, and the related cytokines were evaluated to elucidate underlying mechanism. Blood glucose and lactate were measured at 0 wk (before swimming) and 4 wk (after swimming). RESULTS: HW group showed a higher swimming endurance capacity (p < 0.001) than NC and PW groups. Positive metabolic effects in HW group were revealed by the significant reduction of blood glucose, lactate, and BUN in serum after 4 wk (p < 0.01, resp.), as well as the significant increase of liver glycogen (p < 0.001) and serum LDH (p < 0.05) than PW group. In parallel, redox balance was represented by lower NO in serum (p < 0.01) and increased level of GPx in both serum and liver (p < 0.05) than PW group. In line, the decreased levels of serum TNF-α (p < 0.01), IL-6, IL-17, and liver IL-1ß (p < 0.05) in HW group revealed positive cytokine profile compared to PW and NC group. CONCLUSION: This study shows antifatigue effects of HW drinking in chronic forced swimming mice via metabolic coordination and immune-redox balance. In that context, drinking HW could be applied to the alternative and safety fluid remedy for chronic fatigue control.

Dynamic Photoelectrochemical Device Using an Electrolyte-Permeable NiO x/SiO2/Si Photocathode with an Open-Circuit Potential of 0.75 V.

As a thermodynamic driving force obtained from sunlight, the open-circuit potential (OCP) in photoelectrochemical cells is typically limited by the photovoltage ( Vph). In this work, we establish that the OCP can exceed the value of Vph when an electrolyte-permeable NiO x thin film is employed as an electrocatalyst in a Si photocathode. The built-in potential developed at the NiO x/Si junction is adjusted in situ according to the progress of the NiO x hydration for the hydrogen evolution reaction (HER). As a result of decoupling of the OCP from Vph, a high OCP value of 0.75 V (vs reversible hydrogen electrode) is obtained after 1 h operation of HER in an alkaline electrolyte (pH = 14), thus outperforming the highest value (0.64 V) reported to date with conventional Si photoelectrodes. This finding might offer insight into novel photocathode designs such as those based on tandem water-splitting systems.

Endogenous Agmatine Induced by Ischemic Preconditioning Regulates Ischemic Tolerance Following Cerebral Ischemia.

Ischemic preconditioning (IP) is one of the most important endogenous mechanisms that protect the cells against ischemia-reperfusion (I/R) injury. However, the exact molecular mechanisms remain unclear. In this study, we showed that changes in the level of agmatine were correlated with ischemic tolerance. Changes in brain edema, infarct volume, level of agmatine, and expression of arginine decarboxylase (ADC) and nitric oxide synthases (NOS; inducible NOS [iNOS] and neural NOS [nNOS]) were analyzed during I/R injury with or without IP in the rat brain. After cerebral ischemia, brain edema and infarct volume were significantly reduced in the IP group. The level of agmatine was increased before and during ischemic injury and remained elevated in the early reperfusion phase in the IP group compared to the experimental control (EC) group. During IP, the level of plasma agmatine was increased in the early phase of IP, but that of liver agmatine was abruptly decreased. However, the level of agmatine was definitely increased in the ipsilateral and contralateral hemisphere of brain during the IP. IP also increased the expression of ADC-the enzyme responsible for the synthesis of endogenous agmatine-before, during, and after ischemic injury. In addition, ischemic injury increased endogenous ADC expression in the EC group. The expression of nNOS was reduced in the I/R injured brain in the IP group. These results suggest that endogenous increased agmatine may be a component of the ischemic tolerance response that is induced by IP. Agmatine may have a pivotal role in endogenous ischemic tolerance.

Facile Synthesis of F-TiO2/TiOF2 Mixture by High-Thermal Direct Fluorination and Its Photocatalytic Evaluation.

In this study, the mixture of F-TiO2/TiOF2 has been easily synthesized using titanium (IV) isopropoxide (TTIP) as titanium source by direct fluorination at high temperature according to different partial pressure of fluorine gas. The morphological properties and crystalline of thermally fluorinated photocatalysts were investigated using scanning electron microscope (SEM) and X-ray diffraction (XRD). Chemical composition and optical properties of thermally fluorinated photocatalysts were analyzed by X-ray Photoelectron Spectroscopy (XPS) and Photoluminescence (PL) spectrometer. The phase of F-TiO2/TiOF2 mixture was generated with different proportion by high-thermal direct fluorination. With the increase of the fluorine partial pressure, the proportion of cubic-shaped TiOF2 increased in comparison with globular-shaped TiO2. Also, the degradation rate constant of thermally fluorinated photocatalysts exhibited approximately 70 times more than that of TiO2, which were not treated fluorine gas. It is attributable to the increase of the surface hydroxyl group content and oxygen vacancies.

Pipeline Embolization Device for Large/Giant or Fusiform Aneurysms: An Initial Multi-Center Experience in Korea.

PURPOSE: The purpose of this study was to assess the safety and early outcomes of the Pipeline device for large/giant or fusiform aneurysms. MATERIALS AND METHODS: The Pipeline was implanted in a total of 45 patients (mean age, 58 years; M:F=10:35) with 47 large/giant or fusiform aneurysms. We retrospectively evaluated the characteristics of the treated aneurysms, the periprocedural events, morbidity and mortality, and the early outcomes after Pipeline implantation. RESULTS: The aneurysms were located in the internal carotid artery (ICA) cavernous segment (n=25), ICA intradural segment (n=11), vertebrobasilar trunk (n=8), and middle cerebral artery (n=3). Procedure-related events occurred in 18 cases, consisting of incomplete expansion (n=8), shortening-migration (n=5), transient occlusion of a jailed branch (n=3), and in-stent thrombosis (n=2). Treatment-related morbidity occurred in two patients, but without mortality. Both patients had modified Rankin scale (mRS) scores of 2, but had an improved mRS score of 0 at 1-month follow-up. Of the 19 patients presenting with mass effect, 16 improved but three showed no changes in their presenting symptoms. All patients had excellent outcomes (mRS, 0 or 1) during the follow-up period (median, 6 months; range, 2-30 months). Vascular imaging follow-up (n=31, 65.9%; median, 3 months, range, 1-25 months) showed complete or near occlusion of the aneurysm in 24 patients (77.4%) and decreased sac size in seven patients (22.6%). CONCLUSION: In this initial multicenter study in Korea, the Pipeline seemed to be safe and effective for large/giant or fusiform aneurysms. However, a learning period may be required to alleviate device-related events.

Ozonation of chlortetracycline in the aqueous phase: Degradation intermediates and pathway confirmed by NMR.

Chlortetracycline (CTC) degradation mechanism in aqueous phase ozonation was evaluated for degradation mechanism and its correlation with the biodegradability and mineralization. CTC was removed within 8 and 4 min of ozonation at pH 2.2 and 7.0, respectively. At pH 2.2, HPLC-triple quadrupole mass spectrometry (MS) detected 30 products. The structures for some of these products were proposed on the basis of ozonation chemistry, CTC structure and MS data; these structures were then confirmed by nuclear magnetic resonance (NMR) spectra. Double bond cleavages, dimethyl amino group oxidation, opening and removal of the aromatic ring and dechlorination, mostly direct ozonation reactions, gave products with molecular weights (m.w.) 494, 510, 524, 495 and 413, respectively. Subsequent degradations gave products with m.w. 449, 465, 463 and 415. These products were arranged into a degradation pathway. At pH 7.0, the rate of reaction was increased, though the detected products were similar. Direct ozonation at pH 2.2 increased the biodegradability by altering the structures of CTC and its products. Nevertheless, direct ozonation alone remained insufficient for the mineralization, which was efficient at pH 7.0 due to the production of free radicals.