Aerosol-Synthesized Surfactant-Free Single-Walled Carbon Nanotube-Based NO2 Sensors: Unprecedentedly High Sensitivity and Fast Recovery.

This study pioneers a chemical sensor based on surfactant-free aerosol-synthesized single-walled carbon nanotube (SWCNT) films for detecting nitrogen dioxide (NO2). Unlike conventional CNTs, the SWCNTs used in this study exhibit one of the highest surface-to-volume ratios. They show minimal bundling without the need for surfactants and have the lowest number of defects among reported CNTs. Furthermore, the dry-transferrable and facile one-step lamination results in promising industrial viability. When applied to devices, the sensor shows excellent sensitivity (41.6% at 500 ppb), rapid response/recovery time (14.2/120.8 s), a remarkably low limit of detection (below ≈0.161 ppb), minimal noise, repeatability for more than 50 cycles without fluctuation, and long-term stability for longer than 6 months. This is the best performance reported for a pure CNT-based sensor. In addition, the aerosol SWCNTs demonstrate consistent gas-sensing performance even after 5000 bending cycles, indicating their suitability for wearable applications. Based on experimental and theoretical analyses, the proposed aerosol CNTs are expected to overcome the limitations associated with conventional CNT-based sensors, thereby offering a promising avenue for various sensor applications.

Fountain Pen-Inspired 3D Colloidal Assembly, Consisting of Metallic Nanoparticles on a Femtoliter Scale.

The 3D colloidal assemblies composed of nanoparticles (NPs) are closely associated with optical properties such as photonic crystals, localized surface plasmon resonance, and surface-enhanced Raman scattering. However, research on their fabrication remains insufficient. Here, the femtoliter volume of a 3D colloidal assembly is shown, using the evaporation of a fine fountain pen. A nano-fountain pen (NPF) with a micrometer-level tip inner diameter was adopted for the fine evaporation control of the ink solvent. The picoliters of the evaporation occurring at the NFP tip and femtoliter volume of the 3D colloidal assembly were analyzed using a diffusion equation. The shape of the 3D colloidal assembly was dependent on the evaporation regarding the accumulation time and tip size, and they exhibited random close packing. Using gold-, silver-, and platinum-NPs and mixing ratios of them, diverse 3D colloidal assemblies were formed. The spectra regarding a localized surface plasmon resonance of them were changed according to composition and mixing ratio. We expect that this could be widely applied as a simple fabrication tool in order to explore complex metamaterials constructed of nanoparticles, as this method is highly flexible in varying the shape as well as composition ratio of self-assembled structures.

The Significance of Digital Citizenship and Gender in the Relationship between Social Media Usage Time and Self-Esteem among Adolescents: A Secondary Analysis.

This study examined the significance of digital citizenship and gender in the relationship between social media usage time and self-esteem among adolescents. This cross-sectional study was a secondary analysis using national data on 506 Korean adolescents acquired from the 2020 Korea Media Panel Survey. The data were analyzed using SPSS 23.0 and SPSS PROCESS macro. We found that the moderated moderating effects of digital citizenship and gender on the relationship between social media usage time and self-esteem were significant. Both boys and girls had higher self-esteem in groups with higher digital citizenship than in groups with lower digital citizenship. The relationship between social media usage time and self-esteem for boys was positive in the high digital citizenship group and negative in the low digital citizenship group. Conversely, for girls, the relationship between social media usage time and self-esteem was positive in the low digital citizenship group and negative in the high digital citizenship group. It is important to take a differentiated approach that considers the relationship between digital citizenship and gender to promote healthy digital media use and positive self-esteem.

Digital Citizenship and Life Satisfaction in South Korean Adolescents: The Moderated Mediation Effect of Poverty.

This study examined the moderated mediation effect of poverty on the paths between enactive mastery experience in digital life and life satisfaction mediated by digital citizenship and digital life among Korean adolescents using structural equation modelling. This cross-sectional study involved a secondary data analysis of 2020 national data in The Report on the Digital Divide provided by the National Information Society Agency (NIA) of Korea. Data from 1084 Korean adolescents were analyzed using IBM SPSS Statistics for Windows, version 26.0 and SPSS PROCESS macro. The results demonstrated a significant moderated mediation effect of poverty. Enactive mastery experience, which encompasses the self-knowledge, perceived task difficulty, and contextual factors of adolescents living in poverty, was associated with digital life and life satisfaction through the mediation of digital citizenship. For adolescents living in poverty, in contrast to their non-poor counterparts, enactive mastery experience in digital life and digital citizenship are two critical factors in life satisfaction. Therefore, institutional support enabling adolescents and their communities to forge partnerships is necessary to foster these two factors.

Maternal predictors of children's mental health in low-income families: A structural equation model.

Low-income populations are particularly susceptible to mental health problems, and the susceptibilities of family members may be interconnected. In particular, maternal factors are known to be linked to their children's outcomes. This study aims to investigate how maternal cognition, depression, and the mother-child relationship, as well as children's cognition, predict the mental health of children in low-income families. Pairs of mothers and children from families receiving governmental assistance were surveyed between January 2018 and March 2019. Korean versions of the following instruments were used: Strengths and Difficulties Questionnaire (children's mental health problems), Cognitive Triad Inventory for Children (children's cognition), Kerns' Security Scale (mother-child relationship), Center for Epidemiologic Studies Depression Scale (maternal depression), and Automatic Thoughts Questionnaire-Negative (maternal cognition). A structural equation model was used to examine how maternal cognition, depression, the mother-child relationship, and children's cognition predict children's mental health. Maternal negative cognition and depression mediated by the children's relationships with their mothers negatively predicted their cognition and mental health problems. Enhancing maternal mental health and a mother-child relationship can help improve positive cognition and mental health of children from low-income families.

The Impact of Sleep Quality and Education Level on the Relationship between Depression and Suicidal Ideation in Parents of Adolescents.

This study aimed to analyze the moderating effect of sleep quality and the moderated moderation effect of education level on the relationship between depression and suicidal ideations among middle-aged parents of adolescent children. This is a secondary analysis of a survey collected from a cross-sectional study. The inclusion criteria were middle-aged parents of adolescent children in D city, South Korea, who answered the survey questionnaires. A total of 178 completed questionnaires were used for the analysis. The moderating effect of sleep quality (B = -0.03, p = 0.736) and education level (B = -1.80, p = 0.029) on the relationship between depression and suicidal ideations was shown. It was confirmed that the moderating effect of sleep quality on the effect of depression on suicidal ideations differed according to the subject's education level. The findings have implications for mental healthcare providers who can be educated on sleep hygiene based on the subject's education level.

Effect of depth of anesthesia on the phase lag entropy in patients undergoing general anesthesia by propofol: A STROBE-compliant study.

The PLEM100 (Inbody Co., Ltd., Seoul, Korea) is a device for measuring phase lag entropy (PLE), a recently developed index for the quantification of consciousness during sedation and general anesthesia. In the present study, we assessed changes in PLE along with the level of consciousness during the induction of general anesthesia using propofol. PLE was compared with the bispectral index (BIS), which is currently the most commonly used index of consciousness.After obtaining Institutional Review Board approval and written informed consent, we enrolled 15 patients (8 men, 7 women; mean age: 37 ±â€Š9 years; mean height: 168 ±â€Š8 cm; mean weight; 68 ±â€Š11 kg) undergoing nasal bone reduction. PLE and BIS sensors were attached simultaneously, and general anesthesia was induced via target-controlled infusion (TCI) of propofol. PLE and BIS scores were recorded when the calculated effect site concentration shown on the TCI pump was equal to the target concentrations of 1.5, 2.0, 2.5, 2.8, 3.0, 3.2, 3.4, and 3.5 µg/mL (and at each 0.1 µg/mL increase, thereafter). Observer's Assessment of Alertness/Sedation (OAA/S) scores were also recorded until unconsciousness was achieved. Throughout the anesthesia period, all pairs of PLE and BIS data were collected using data acquisition software.The partial correlation coefficients between OAA/S scores and PLE, and between OAA/S scores and BIS were 0.778 (P < .001) and 0.846 (P < .001), respectively. Throughout the period of anesthesia, PLE and BIS exhibited a significant positive correlation. The partial correlation coefficient prior to the loss of consciousness was 0.838 (P < .001), and 0.669 (P < .001) following the loss of consciousness. Intra-class correlation between the 2 indices was 0.889 (P < .001) and 0.791 (P < .001) prior and following the loss of consciousness, respectively.PLE exhibited a strong and predictable correlation with both BIS and OAA/S scores. These results suggest that PLE is reliable for assessing the level of consciousness during sedation and general anesthesia.

Association between shift work and severity of depressive symptoms among female nurses: the Korea Nurses' Health Study.

AIM: To determine the prevalence of depression and the relationship between shift work and depression severity among female nurses in South Korea. BACKGROUND: Shift work has been associated with higher risks of depressive symptoms, but there is a dearth of research on nurses, particularly investigating the severity of depressive symptoms. METHODS: Quantitative data including survey response from 9789 participants were analysed. Statistical analysis included descriptive, Spearman's correlation and multivariable ordinal logistic regression. RESULTS: The numbers of nurses according to the severity of depressive symptoms were 35.2% (n = 3445), 38.0% (n = 3716), 16.1% (n = 1578), 7.6% (n = 747) and 3.1% (n = 303) for normal, mild, moderate, severely moderate and severe level of depressive symptoms, respectively. After adjusting for sociodemographic and health behavioural factors, nurses who worked shifts had 1.519-times greater odds of experiencing a higher severity of depressive symptoms (OR = 1.519, CI = 1.380-1.674, P < 0.001). CONCLUSION: This study shows a higher prevalence of depressive symptoms among nurses who worked shifts and suggests that shift work may increase the severity of depressive symptoms among female nurses in South Korea. IMPLICATIONS FOR NURSING MANAGEMENT: Nursing professionals, managers and health policy makers need to understand the factors influencing depressive symptoms and to use appropriate interventions based on the severity and not just the onset.

Influence of various gypsum materials on precision of fit of CAD/CAM-fabricated zirconia copings.

The clinical applicability of CAD/CAM-fabricated zirconia copings is tested using working models made from four different highstrength Type IV gypsum materials. Each of the four materials was used to fabricate 15 zirconia copings. Precision of fit was measured with a digital electron microscope using the silicone replica technique. The mean and standard deviation of each reference point were analyzed using the one-way analysis of the variance (ANOVA) and Tukey's honest significant difference (HSD) tests (α=0.05). The overall marginal and internal fits of the zirconia copings were as follows: GS (GS: Grey Stone) group: 91.43 µm, LS (LS: Light green Stone) Group: 87.89 µm, RS (RS: Red Stone) Group: 88.75 µm, BS (BS: Beige Stone) Group: 82.78 µm. There were no significant differences between the mean adaptations of the gypsum varieties (p>0.05). This confirmed that the type of gypsum material used does not determine the precision of fit of a prosthesis.

Frozen Section Biopsy to Evaluation of Obscure Lateral Resection Margins during Gastric Endoscopic Submucosal Dissection for Early Gastric Cancer.

PURPOSE: To determine the diagnostic utility of a frozen section biopsy in patients undergoing endoscopic submucosal dissection (ESD) for early gastric neoplasms with obscure margins even with chromoendoscopy using acetic acid and indigo carmine (AI chromoendoscopy). MATERIALS AND METHODS: The lateral spread of early gastric neoplasms was unclear even following AI chromoendoscopy in 38 patients who underwent ESD between June 2007 and May 2011. Frozen section biopsies were obtained by agreement of the degree of lateral spread between two endoscopists. Thus, frozen section biopsies were obtained from 23 patients (FBx group) and not in the other 15 patients (AI group). RESULTS: No significant differences were observed for size, histology, invasive depth, and location of lesions between the AI and FBx groups. No false positive or false negative results were observed in the frozen section diagnoses. Adenocarcinoma was revealed in three patients and tubular adenoma in one, thereby changing the delineation of lesion extent and achieving free lateral margins. The rates of free lateral resection margins and curative resection were significantly higher in the FBx group than those in the AI group. CONCLUSIONS: Frozen section biopsy can help endoscopists perform more safe and accurate ESD in patients with early gastric neoplasm.