Despite the ongoing outbreak of the novel COVID-19, few studies have been conducted on the stress arising from the pandemic. In this study, attributes of epidemic concerns perceived by hotel ...employees were examined, and their impact on work stress, employee well-being, self-rated mental health, organizational citizenship behavior, and employee-customer identification were verified. We found and verified four attributes based on qualitative and quantitative approaches. As a result of the structural equation analysis, it was found that the relationships between the proposed variables had significant effects. This study provides important insights into the impact of epidemics on hotel employee performance through the attributes of perceived epidemic concerns.
Enhancing and spectrally controlling light absorption is of great practical and fundamental importance. In optoelectronic devices consisting of layered semiconductors and metals, absorption has ...traditionally been manipulated with the help of Fabry-Pérot resonances. Even further control over the spectral light absorption properties of thin films has been achieved by patterning them into dense arrays of subwavelength resonant structures to form metafilms. As the next logical step, we demonstrate electrical control over light absorption in metafilms constructed from dense arrays of actively tunable plasmonic cavities. This control is achieved by embedding indium tin oxide (ITO) into these cavities. ITO affords significant tuning of its optical properties by means of electrically-induced carrier depletion and accumulation. We demonstrate that particularly large changes in the reflectance from such metafilms (up to 15% P) can be achieved by operating the ITO in the epsilon-near-zero (ENZ) frequency regime where its electrical permittivity changes sign from negative to positive values.
Botulinum toxin (BoNT) has been used as a treatment for excessive muscle stiffness, spasticity, and dystonia. BoNT for approximately 40 years, and has recently been used to treat various types of ...neuropathic pain. The mechanism by which BoNT acts on neuropathic pain involves inhibiting the release of inflammatory mediators and peripheral neurotransmitters from sensory nerves. Recent journals have demonstrated that BoNT is effective for neuropathic pain, such as postherpetic neuralgia, trigeminal neuralgia, and peripheral neuralgia. The purpose of this review is to summarize the experimental and clinical evidence of the mechanism by which BoNT acts on various types of neuropathic pain and describe why BoNT can be applied as treatment. The PubMed database was searched from 1988 to May 2017. Recent studies have demonstrated that BoNT injections are effective treatments for post-herpetic neuralgia, diabetic neuropathy, trigeminal neuralgia, and intractable neuropathic pain, such as poststroke pain and spinal cord injury.
High order plasmonic Bragg reflection in the metal-insulatormetal (MIM) waveguide Bragg grating (WBG) and its applications are proposed and demonstrated numerically. With the effective index method ...and the standard transfer matrix method, we reveal that there exist high order plasmonic Bragg reflections in MIM WBG and corresponding Bragg wavelengths can be obtained. Contrary to the high order Bragg wavelengths in the case of the conventional dielectric slab waveguide, the results of the MIM WBG exhibit red shifts of tens of nanometers. We also propose a method to design a MIM WBG to have high order plasmonic Bragg reflection at a desired wavelength. The MIM WBG operating in visible spectral regime, which requires quite accurate fabrication process with grating period of 100 to 200 nm for the fundamental Bragg reflection, can be implemented by using the higher order plasmonic Bragg reflection with grating period of 400 to 600 nm . It is shown that the higher order plasmonic Bragg reflection can be em ployed to implement a narrow reflection bandwidth as well. We also address the dependence of the filling factor upon the bandgap and discuss the quarter-wave stack condition and the second bandgap closing.
Human umbilical cord mesenchymal stem cells (MSCs) have been reported to improve the migration and invasion of trophoblast cells; however, little is known about whether MSC-derived exosomes and ...exosomal miRNAs can regulate trophoblast cell properties. In this study, we investigated whether exosomal miRNAs from amniotic fluid-derived MSC (AF-MSC) could regulate the inflammatory response of the human trophoblast cell line HTR8/SVneo. We verified the anti-inflammatory effects of AF-MSCs on lipopolysaccharide (LPS)-induced inflammatory trophoblast cells and found that miR-146a-5p and miR-548e-5p in the AF-MSC-derived exosomes regulate nuclear factor κB, AKT and mitogen-activated protein kinase protein phosphorylation. Furthermore, we found that the transfection of human trophoblast cells with miR-146a-5p and miR-548e-5p inhibitors reduced trophoblast migration (P < 0.05 vs control) and the expression of proliferating cell nuclear antigen, a protein essential for cell proliferation (P < 0.01 vs control). In particular, the miR-548e-5p inhibitor induced apoptosis, while tumor necrosis factor receptor-associated factor 6, a predicted target of miR-146a-5p and miR-548e-5p, was involved in the regulation of oxidative stress in the human trophoblast cells. In a mouse model of LPS-induced preterm birth (PB), miR-146a-5p expression was found to be relatively low in the group in which the effect of AF-MSCs was insignificant. However, this study is limited in that the changes in the expression of some genes in response to AF-MSCs differ between the cell line and mouse model. Collectively, these data show that exosomal miR-146a-5p and miR-548e-5p from AF-MSCs have anti-inflammatory effects on human trophoblast cells and may be novel targets for treating inflammatory diseases and associated problems that occur during pregnancy, such as PB.
Recently developed micro- and nano-structured optical fiber sensors, with particular reference to surface plasmon resonance (SPR) fiber sensors and photonic crystal fiber (PCF) sensors are reviewed. ...SPR fiber sensors can have diverse structures such as D-shape, cladding-off, fiber tip or tapered fiber structures. Some of the recently developed novel structures include the use of various types of fiber gratings in SPR fiber sensors. PCF sensors cover diverse recent developments on photonic-bandgap fiber, holey fiber, hole-assisted fiber and Bragg fiber sensors. Major applications of these include gas sensors and bio-sensors. These micro- and nano-structured fiber sensors have attracted considerable research and development interest, because of their distinct advantages, which include high sensitivity, small sensor head footprint and the flexibility of the optical fibers. They are also of academic interest, and many novel ideas are continuously developed.
Depression represents a widespread and devastating psychiatric public health challenge globally. It is particularly prevalent among young adults in Korea. Certain foods may have medicinal properties ...that alleviate depressive symptoms. This study aimed to examine the association between specific foods and depressive symptoms among young adults, exploring their bioactive effects and possible mechanisms. We conducted a cross-sectional study involving 1000 Korean young adults aged 18–39 years. Food frequency questionnaires were used to assess diets and their associations with depressive symptoms. Results from multivariable logistic regression analysis indicated associations between several specific foods and their effects: milk (odds ratio = 0.58, 95% confidence interval: 0.36–0.94), eggs (0.55, 0.35–0.87), bananas (0.58, 0.36–0.94), oranges (0.62, 0.40–0.96), sweet potatoes (0.60, 0.37–0.97), mushrooms (0.53, 0.31–0.92, females only), and kimchi (0.40, 0.17–0.95, males only). Furthermore, molecular docking indicated that hesperidin had the highest docking score of 5.86 in oranges. Several bioactive compounds identified as potentially beneficial in combatting depression include calcium, casein, alpha-lactalbumin, tryptophan (TRP), vitamin B6 and B12, magnesium, flavonoids (especially hesperidin), carotenoids, ergothioneine, fiber, and probiotics. To recommend these foods in the management of depression among young adults, further clinical intervention studies are necessary.
Abstract
The ability of controlling the phase of light at the subwavelength scale can be a game-changer due to its extraordinally wide angle-range in the wavefront shaping. By combining two ...conventional material and configuration, liquid crystal and distributed Bragg reflectors, we are getting close to this ultimate goal.
The anti-obesity effect of milk intake has been suggested via a variety of designed studies, but findings of obesity interventions for adult Koreans are scarcely reported. The study aimed to ...investigate the anti-obesity effect of cow's milk in adult Koreans with an 8-wk randomized intervention. A total of 121 adults with overweight aged 19 to 60 years old were randomly assigned to one of the 2 groups: milk or control. During the intervention, both groups were encouraged 500kcal restriction a day and the milk group consumed 200mL milk twice a day, the same energy intake as the control group, including milk intake, was recommended for 8 weeks. There were no significant differences in body weight and BMI between the milk and control groups during the 8-wk intervention although, the changes in body weight and BMI of those within the milk group were significant. High-density lipoprotein cholesterol levels and serum calcium levels increased significantly in the milk group compared with the control group. Calcium, phosphorus, vitamin A, and riboflavin intakes increased significantly, when compared with the control. In conclusion, 8-wk milk consumption had no effect on weight loss and BMI change but improved some blood biomarkers and nutrient intake in Korean adults with overweight. To evaluate the effect of milk on obesity reduction, well-designed, long-term, and large-scale studies are needed.
PDF
