The associations of Internet addiction (IA) and smartphone addiction (SA) with mental health problems have been widely studied. We investigated the effects of IA and SA on depression and anxiety ...while adjusting for sociodemographic variables. In this study, 4854 participants completed a cross-sectional web-based survey including socio-demographic items, the Korean Scale for Internet Addiction, the Smartphone Addiction Proneness Scale, and the subscales of the Symptom Checklist 90 Items-Revised. The participants were classified into IA, SA, and normal use (NU) groups. To reduce sampling bias, we applied the propensity score matching method based on genetics matching. The IA group showed an increased risk of depression (relative risk 1.207;
< 0.001) and anxiety (relative risk 1.264;
< 0.001) compared to NUs. The SA group also showed an increased risk of depression (relative risk 1.337;
< 0.001) and anxiety (relative risk 1.402;
< 0.001) compared to NCs. These findings show that both, IA and SA, exerted significant effects on depression and anxiety. Moreover, our findings showed that SA has a stronger relationship with depression and anxiety, stronger than IA, and emphasized the need for prevention and management policy of the excessive smartphone use.
Promoting fathers' parental leave has recently become of major policy interest in many welfare states. The Korean Government also introduced paid parental leave for working fathers in 2001 and has ...increasingly strengthened such incentive schemes. However, despite its rapid advancement, fathers' utilisation of parental leave is increasing slowly and most fathers still opt out of their responsibilities for childcare. As sociocultural norms are a primary cause of this low take‐up behaviour pattern, this study focuses on the Confucian relational ethics deeply embedded in Korean society. Through in‐depth interviews with 15 Korean working couples, this article demonstrates how Confucian relational ethics constrain fathers from enjoying their individual right to parental leave by designating them as last‐resort caregivers within families and as forefront workers in the workplace. This study shows the importance of the sociocultural grounding of a society to ordinary citizens when they utilise a social policy in their daily lives.
Runx2 plays essential roles in bone formation and chondrocyte maturation. Akt promotes osteoblast differentiation induced by the bone morphogenetic proteins BMP2 and enhances the function and ...transcriptional activity of Runx2. However, the precise molecular mechanism underlying the relationship between Runx2 and Akt is not well understood. In this study, we examined the role of Akt in regulating Runx2 function. We found that Akt increases the stability of Runx2 protein. However, the level of Runx2 mRNA was not affected by Akt, and we did not find any evidence for direct modification of Runx2 by Akt. Instead, we found evidence that Akt induces the phosphorylation of the Smad ubiquitination regulatory factor Smurf2 and decreases the level of Smurf2 protein through ubiquitin/proteasome‐mediated degradation of Smurf2. Akt also alleviates Smurf2‐mediated suppression of Runx2 transcriptional activity. Taken together, our results suggest that Akt regulates osteoblast differentiation, at least in part, by enhancing the protein stability and transcriptional activity of Runx2 through regulation of ubiquitin/proteasome‐mediated degradation of Smurf2.
Akt increases the stability of Runx2 protein. But the level of Runx2 mRNA was not affected by Akt and we could not detect any evidence for direct modification of Runx2 by Akt. Akt induces the phosphorylation of Smurf2 and decreases the level of Smurf2 protein through ubiquitin‐proteasome‐mediated degradation of Smurf2. Akt also alleviates Smurf2‐mediated suppression of Runx2 transcriptional activity.
Chitosan‐functionalized graphene oxides (FGOCs) were successfully synthesized. FGOCs were found to significantly improve the solubility of the GO in aqueous acidic media. The presence of organic ...groups was confirmed by means of XPS and TGA. Restoration of the sp2 carbon network and exfoliation of graphene sheets were confirmed by Raman spectroscopy, UV‐visible spectroscopy and WAXD. The SEM and AFM investigations of the resultant FGOCs showed that most of the graphene sheets were individual and few were layered. Controlled release behavior of Ibuprofen and 5‐fluorouracil was then investigated. We found that FGOCs are a promising new material for biological and medical applications.
GO is successfully functionalized with chitosan. The excellent exfoliation and dispersion of functionalized graphene sheets in aqueous acetic acid solution are presented. Moreover, IBU and 5‐FU are loaded successfully on FGOCs sheets, despite fewer π electrons. The controlled release behavior and long‐term biocompatibility of FGOCs graphene sheets suggest that they are promising novel materials for biomedical applications.
•Fucoidan was successfully depolymerized using SCW treatment.•BBD was used to find the best conditions of antioxidant and chemical composition of fucoidan.•The best conditions was found to be 214 °C, ...40 bar, 60 mL/g, 223 RPM and 5 min.•Low molecular weight of fucoidan was obtained from SCW treatment.•The optimized condition showed improved biological activities from native fucoidan.
Fucoidan is a marine sulfated polysaccharide that possesses various biological activities. To enhance the functional properties of fucoidan, it was depolymerized using a green technique viz. subcritical water treatment (SCW) to produce a low molecular weight fucoidan. In this study, response surface methodology (RSM) was used to study the influence of different influences for instance temperature, pressure, liquid to solid ratio, and agitation speed to depolymerize fucoidan. RSM was used to focus on the antioxidant activity and chemical composition of SCW-treated fucoidan. Further, resulting SCW-treated fucoidan was investigated by UV-Vis, FT-IR, Thermal gravimetric analysis (TGA), DSC, Elemental analysis, and ESI-MS. Moreover, the optimized SCW-treated fucoidan was checked for cytotoxicity, antimicrobial, antidiabetic, and anticoagulant activity compared with the untreated fucoidan. The obtained values displayed that SCW treatment breakdowns polymer chain and so it produces low molecular weight fucoidan. Biological activities were improved as the molecular weight was reduced.
An exact matrix method, originally proposed for evaluating effective elastic constants of generally anisotropic multilayer composites, is further developed for a micromechanical analysis of ...multilayers with various coupled physical effects including piezoelectricity, piezomagnetism, thermoelasticity (in consideration of entropy), and the Biot’s poroelasticity. The results for a BaTiO
3–CoFe
2O
4 magneto-electro-thermo-elastic (METE) multilayer coincide with those calculated using other micromechanical models based on the Mori–Tanaka method and the asymptotic homogenization method. It is shown that the present method can efficiently handle the most general type of multilayers with an arbitrary number of general anisotropic layers. Analytical expressions for effective material properties of a transversely isotropic METE multilayer composite are derived, from which those for functionally graded METE multilayers can be directly obtained. The effects of crystallographic orientations and volume fractions of constituting layers on the magnetoelectric coefficients are investigated for BaTiO
3–CoFe
2O
4 and LiNbO
3–CoFe
2O
4 multilayer composites. It is thus demonstrated that the present model can be used for the layout/material optimization of these METE multilayers to obtain a maximum product property such as the magnetoelectric, pyroelectric, and pyromagnetic coefficients. It is also shown that the same method can be used to predict the effective properties of poroelastic multilayers.
The dual-phase AlCoCrFeNi alloy exhibits excellent specific strength in the 773–873 K temperature range. However, the phase transformation taking place above 773 K hinders its structural use at ...higher temperatures. In the present study, the temperature dependence of the specific strength of the AlCoCrFeNi alloy has been examined from a microstructural point of view. One of the key findings of this work is that the high-temperature phase stability of the dual-phase alloy is strongly affected by its microstructural morphology; this finding provides new insights into the application of high-entropy alloys as high-temperature structural materials, for instance in aerospace engine components.
•AlCoCrFeNi alloy exhibits excellent specific strength in 773–873 K temperature range.•The yield strength of the AlCoCrFeNi alloy exhibits a sharp drop above 773 K.•The maximum-use temperature can be increased by suppressing the phase transformation.
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