Chemically modulated graphene quantum dot for tuning the photoluminescence as novel sensory probe

A band gap tuning of environmental-friendly graphene quantum dot (GQD) becomes a keen interest for novel applications such as photoluminescence (PL) sensor. Here, for tuning the band gap of GQD, a hexafluorohydroxypropanyl benzene (HFHPB) group acted as a receptor of a chemical warfare agent was chemically attached on the GQD via the diazonium coupling reaction of HFHPB diazonium salt, providing new HFHPB-GQD material. With a help of the electron withdrawing HFHPB group, the energy band gap of the HFHPB-GQD was widened and its PL decay life time decreased. As designed, after addition of dimethyl methyl phosphonate (DMMP), the PL intensity of HFHPB-GQD sensor sharply increased up to approximately 200% through a hydrogen bond with DMMP. The fast response and short recovery time was proven by quartz crystal microbalance (QCM) analysis. This HFHPB-GQD sensor shows highly sensitive to DMMP in comparison with GQD sensor without HFHPB and graphene. In addition, the HFHPB-GQD sensor showed high selectivity only to the phosphonate functional group among many other analytes and also stable enough for real device applications. Thus, the tuning of the band gap of the photoluminescent GQDs may open up new promising strategies for the molecular detection of target substrates. © The Author(s) 20166511sciescopu

Effect of Stress on Quality of Life of Shift Nurses in Tertiary General Hospital: The Mediating Effect of Mindfulness

The purpose of this study was to examine the mediating effects of mindfulness on the relationships between stress and quality of life among shift nurses. A descriptive cross-sectional survey design was conducted using purposive sampling of 206 shift nurses in a tertiary general hospital in Korea. Data were analyzed with descriptive statistics, Pearson correlation and multiple regression analysis using SPSS/WIN 26.0 program. There were significant correlations among stress, mindfulness and quality of life. The quality of life had a positive correlation with mindfulness (r = 0.52, p < 0.001) and a negative correlation with stress among nurses. Mindfulness acts as a mediator in explaining relationship between stress and quality of life. This study provide evidence for the role of mindfulness in the relationship between stress and quality of life in shift nurses. Mindfulness appears to be a protective factor against nurses’ stress. If mindfulness-based interventions are developed and applied to improve the quality of life of shift nurses based on this study, it can help reduce their stress and improve the quality of life, which could ultimately improve the quality of nursing care for patients

Factors Affecting the Quality of Work Life of Nurses at Tertiary General Hospitals in the Context of the COVID-19 Pandemic

The prolonged coronavirus disease 2019 (COVID-19) pandemic has caused an overload of work for nurses and resulted in high levels of stress. Improving the quality of work life may be a useful mediator for these demands. The purpose of this study was to identify factors affecting work stress, turnover intention, mindfulness, and quality of work life in nurses working in tertiary general hospitals. The participants of this study were 207 female nurses working in tertiary general hospitals with more than six months of clinical experience. Data were collected using an online Google survey. Data were analyzed using the SPSS/WIN 26.0 program. The mean score for the quality of work life was 3.81 &plusmn; 0.53 out of six points. The quality of work life was negatively correlated with job stress (r = &minus;0.36, p &lt; 0.001) and turnover intention (r = &minus;0.45, p &lt; 0.001) and positively correlated with mindfulness (r = 0.35, p &lt; 0.001). Factors affecting quality of work life were work satisfaction (&beta; = 0.27, p = 0.004), job stress (&beta; = &minus;0.23, p &lt; 0.001), and turnover intention (&beta; = &minus;0.18, p = 0.016). As a result, positive factors such as work satisfaction had stronger effects than negative factors. Thus, it would be necessary to seek strategies such as improving compensation for nurses, enhancing teamwork, or establishing a support system for managers, superiors, and colleagues

Effect of Sleep Quality and Depression on Married Female Nurses’ Work–Family Conflict

Married female nurses experience work–family conflict (WFC) as they manage excessive work and various working-hour types while rearing children and tending household chores, and as a result, they continuously constantly deliberate over quitting their job or moving to a different workplace. Married nurses were found to have shorter sleep duration and sleep latency compared to single nurses, and high job stress not only hinders their family life but also causes sleep problems. Depression is a classic negative emotion experienced by married working women who must manage both work and family. This study aims to examine WFC in married female nurses and investigate its predictors, namely depression and sleep quality. A total of 229 married female nurses completed a Google questionnaire link consisting of the Work–Family Conflict Scale, Sleep-Quality Scale, and the Center for Epidemiologic Studies Depression Scale (CES-D). Data were analyzed by descriptive statistics, t-test, ANOVA, LSD post hoc test, Pearson’s correlation coefficients, and multiple regression using the SPSS/WIN 26.0 program. The average WFC score was 4.84 ± 1.12 (range 1–7); WFC showed a statistical difference according to a stage of the lifecycle (F = 7.12, p = 0.001) and perceived health (F = 12.01, p &lt; 0.001). WFC was low among those in the non-parenthood stage of the lifecycle (β = −0.26, p &lt; 0.001), those with good (β = −0.18, p = 0.011) or moderate perceived health (β = −0.15, p = 0.023), and those without turnover intention (β = −0.13, p = 0.016). On the other hand, WFC was high among those who were extremely dissatisfied with their job (β = 0.16, p = 0.008) and those who had a high level of depression (β = 0.22, p = 0.002); these variables explained 20.2% of WFC (F = 7.663, p &lt; 0.001). Based on these results, subsequent studies should develop and implement coping programs that help reduce WFC and improve depression and sleep quality in married female nurses

Initial Clinical Practicum Stress among Nursing Students: A Cross-Sectional Study on Coping Styles

Nursing students experience various stressors during their initial clinical practicum. As these stressors negatively affect learning and performance, coping strategies are essential. Therefore, this research study explored the relationship between coping styles and stress levels using a cross-sectional study with a convenience sample of 184 nursing students. Clinical practicum stress and coping styles were assessed via electronic questionnaires, and the data were analyzed using descriptive statistics, t-tests, and variance analyses. The highest score for clinical practice stress was for the practical education environment and practical work burden. The total stress score differed significantly according to coping style (t = −2.36, p = 0.020), and the total stress score of the passive coping group was higher. Among the sub-categories of stress, the scores of the education environment (t = −2.68, p = 0.008) and having undesirable role models (t = −2.14, p = 0.034) were significantly higher in the passive coping group. Although practical work burden was the highest stress factor in the active coping style group, the stress on the environment was highest in the passive coping group. The findings show that professors and clinical educators should recognize the various coping styles and incorporate different teaching methods in the clinical setting

Mesoporous Non-stacked Graphene-receptor Sensor for Detecting Nerve Agents

A novel gas sensor consisting of porous, non-stacked reduced graphene oxide (NSrGO)-heaxfluorohydoroxypropanyl benzene (HFHPB) nanosheets was successfully fabricated, allowing the detection of dimethyl methyl phosphonate (DMMP), similar to sarin toxic gas. The HFHPB group was chemically grafted to the NSrGO via a diazotization reaction to produce NSrGO-HFHPB. The NSrGO-HFHPB 3D film has a mesoporous structure with a large pore volume and high surface area that can sensitively detect DMMP and concurrently selectively signal the DMMP through the chemically-attached HFHPB. The DMMP uptake of the mesoporous NSrGO-HFHPB was 240.03 Hz, 12 times greater than that of rGO-HFHPB (20.14 Hz). In addition, the response rate of NSrGO-HFHPB was faster than that of rGO-HFHPB, an approximately 3 times more rapid recovery due to the mesoporous structure of the NSrGO-HFHPB. The NSrGO-HFHPB sensor exhibited long-term stability due to the use of robust carbon and resulting high resistance to humidity © The Author(s) 2016101sciescopu

FeIn2S4 Nanocrystals: A Ternary Metal Chalcogenide Material for Ambipolar Field-Effect Transistors

An ambipolar channel layer material is required to realize the potential benefits of ambipolar complementary metal-oxide-semiconductor field-effect transistors, namely their compact and efficient nature, reduced reverse power dissipation, and possible applicability to highly integrated circuits. Here, a ternary metal chalcogenide nanocrystal material, FeIn2S4, is introduced as a solution-processable ambipolar channel material for field-effect transistors (FETs). The highest occupied molecular orbital and the lowest unoccupied molecular orbital of the FeIn2S4 nanocrystals are determined to be -5.2 and -3.75 eV, respectively, based upon cyclic voltammetry, X-ray photoelectron spectroscopy, and diffraction reflectance spectroscopy analyses. An ambipolar FeIn2S4 FET is successfully fabricated with Au electrodes (E-F = -5.1 eV), showing both electron mobility (14.96 cm(2) V-1 s(-1)) and hole mobility (9.15 cm(2) V-1 s(-1)) in a single channel layer, with an on/off current ratio of 10(5). This suggests that FeIn2S4 nanocrystals may be a promising alternative semiconducting material for next-generation integrated circuit developmen

Facile C–H arylation using catalytically active terminal sulfurs of 2 dimensional molybdenum disulfide

The first methodology of C–H arylation of heteroarene via 2D transition metal dichalcogenides that have catalytically active edge functional groups was described. The terminal sulfur groups could effectively catalyze a formation of an azo-linked intermediate with aryl diazonium salts, leading to produce heteroarenes with good yields. This novel methodology using bulk 2D transition metal dichalcogenides that have catalytically active edge functional groups can apply for various reactions to achieve C–C bond formation in the fields of heterogeneous catalysis that is easily separable, highly reusable, and inexpensive method. © 2018 Elsevier L

Superconductivity at 7.4 K in few layer graphene by Li-intercalation

Superconductivity in graphene has been highly sought after for its promise in various device applications and for general scientific interest. Ironically, the simple electronic structure of graphene, which is responsible for novel quantum phenomena, hinders the emergence of superconductivity. Theory predicts that doping the surface of the graphene effectively alters the electronic structure, thus promoting propensity towards Cooper pair instability (Profeta et al (2012) Nat. Phys. 8 131-4; Nandkishore et al (2012) Nat. Phys. 8 158-63) [1, 2]. Here we report the emergence of superconductivity at 7.4 K in Li-intercalated few-layer-graphene (FLG). The absence of superconductivity in 3D Li-doped graphite underlines that superconductivity in Li-FLG arises from the novel electronic properties of the 2D graphene layer. These results are expected to guide future research on graphene-based superconductivity, both in theory and experiments. In addition, easy control of the Li-doping process holds promise for various device applications. © 2017 IOP Publishing Ltd Printed in the UK1241sciescopu