Optical Probing of Electronic Interaction between Graphene and Hexagonal Boron Nitride

Even weak van der Waals (vdW) adhesion between two-dimensional solids may perturb their various materials properties owing to their low dimensionality. Although the electronic structure of graphene has been predicted to be modified by the vdW interaction with other materials, its optical characterization has not been successful. In this report, we demonstrate that Raman spectroscopy can be utilized to detect a few % decrease in the Fermi velocity (vF) of graphene caused by the vdW interaction with underlying hexagonal boron nitride (hBN). Our study also establishes Raman spectroscopic analysis which enables separation of the effects by the vdW interaction from those by mechanical strain or extra charge carriers. The analysis reveals that spectral features of graphene on hBN are mainly affected by change in vF and mechanical strain, but not by charge doping unlike graphene supported on SiO2 substrates. Graphene on hBN was also found to be less susceptible to thermally induced hole doping.Comment: 19 pages, 4 figure

Nanostructured, Self-Assembling Peptide K5 Blocks TNF-α and PGE2 Production by Suppression of the AP-1/p38 Pathway

Nanostructured, self-assembling peptides hold promise for a variety of regenerative medical applications such as 3D cell culture systems, accelerated wound healing, and nerve repair. The aim of this study was to determine whether the self-assembling peptide K5 can be applied as a carrier of anti-inflammatory drugs. First, we examined whether the K5 self-assembling peptide itself can modulate various cellular inflammatory responses. We found that peptide K5 significantly suppressed the release of tumor-necrosis-factor- (TNF-) α and prostaglandin E2 (PGE2) from RAW264.7 cells and peritoneal macrophages stimulated by lipopolysaccharide (LPS). Similarly, there was inhibition of cyclooxygenase- (COX-) 2 mRNA expression assessed by real-time PCR, indicating that the inhibition is at the transcriptional level. In agreement with this finding, peptide K5 suppressed the translocation of the transcription factors activator protein (AP-1) and c-Jun and inhibited upstream inflammatory effectors including mitogen activated protein kinase (MAPK), p38, and mitogen-activated protein kinase kinase 3/6 (MKK 3/6). Whether this peptide exerts its effects via a transmembrane or cytoplasmic receptor is not clear. However, our data strongly suggest that the nanostructured, self-assembling peptide K5 may possess significant anti-inflammatory activity via suppression of the p38/AP-1 pathway

Role of interleukin-10 in endochondral bone formation in mice: Anabolic effect via the bone morphogenetic protein/Smad pathway

Objective: Interleukin-10 (IL-10) is a pleiotropic immunoregulatory cytokine with a chondroprotective effect that is elevated in cartilage and synovium in patients with osteoarthritis. However, the role of IL-10 during endochondral bone formation and its mechanism of action have not been elucidated. Methods: IL-10-/- mice and IL-10-treated tibial organ cultures were used to study loss and gain of IL-10 functions, respectively, during endochondral bone formation. Primary chondrocytes from the long bones of mouse embryos were cultured with and without IL-10. To assess the role of IL-10 in chondrogenic differentiation, we conducted mesenchymal cell micromass cultures. Results: The lengths of whole skeletons from IL-10-/- mice were similar to those of their wild-type littermates, although their skull diameters were smaller. The tibial growth plates of IL-10-/- mice showed shortening of the proliferating zone. Treatment with IL-10 significantly increased tibial lengths in organ culture. IL-10 also induced chondrocyte proliferation and hypertrophic differentiation in primary chondrocytes in vitro. Mechanistically, IL-10 activated STAT-3 and the Smad1/5/8 and ERK-1/2 MAP kinase pathways and induced the expression of bone morphogenetic protein 2 (BMP-2) and BMP-6 in primary chondrocytes. Furthermore, the blocking of BMP signaling attenuated the IL-10-mediated induction of cyclin D1 and RUNX-2 in primary chondrocytes and suppressed Alcian blue and alkaline phosphatase staining in mesenchymal cell micromass cultures. Conclusion: These results indicate that IL-10 acts as a stimulator of chondrocyte proliferation and chondrogenic or hypertrophic differentiation via activation of the BMP signaling pathway. © 2013, American College of Rheumatology

Risk factors associated with death due to severe fever with thrombocytopenia syndrome in hospitalized Korean patients (2018–2022)

Objectives Severe fever with thrombocytopenia syndrome (SFTS) has no vaccine or treatment and an extremely high fatality rate. We aimed to analyze and evaluate the risk factors for death associated with SFTS. Methods Among reports from 2018 to 2022, we compared and analyzed 1,034 inpatients aged 18 years or older with laboratory-confirmed SFTS who underwent complete epidemiological investigations. Results Most of the inpatients with SFTS were aged 50 years or older (average age, 67.6 years). The median time from symptom onset to death was 9 days, and the average case fatality rate was 18.5%. Risk factors for death included age of 70 years or older (odds ratio [OR], 4.82); agriculture-related occupation (OR, 2.01); underlying disease (OR, 7.20); delayed diagnosis (OR, 1.28 per day); decreased level of consciousness (OR, 5.53); fever/chills (OR, 20.52); prolonged activated partial thromboplastin time (OR, 4.19); and elevated levels of aspartate aminotransferase (OR, 2.91), blood urea nitrogen (OR, 2.62), and creatine (OR, 3.21). Conclusion The risk factors for death in patients with SFTS were old age; agriculture-related occupation; underlying disease; delayed clinical suspicion; fever/chills; decreased level of consciousness; and elevated activated partial thromboplastin time, aspartate aminotransferase, blood urea nitrogen, and creatine levels

Prevalence and characteristics of foodborne pathogens from slaughtered pig carcasses in Korea

The introduction of bacteria into slaughterhouses can lead to microbial contamination in carcasses during slaughter, and the initial level of bacteria in carcasses is important because it directly affects spoilage and the shelf life. This study was conducted to investigate the microbiological quality, and the prevalence of foodborne pathogens in 200 carcasses from 20 pig slaughterhouses across Korea. Distribution of microbial counts were significantly higher for aerobic bacteria at 3.01–4.00 log10 CFU/cm2 (42.0%) and 2.01–3.00 log10 CFU/cm2 (28.5%), whereas most of Escherichia coli showed the counts under 1.00 log10 CFU/cm2 (87.0%) (P < 0.05). The most common pathogen isolated from 200 carcasses was Staphylococcus aureus (11.5%), followed by Yersinia enterocolitica (7.0%). In total, 17 S. aureus isolates from four slaughterhouses were divided into six pulsotypes and seven spa types, and showed the same or different types depending on the slaughterhouses. Interestingly, isolates from two slaughterhouses carried only LukED associated with the promotion of bacterial virulence, whereas, isolates from two other slaughterhouses carried one or more toxin genes associated with enterotoxins including sen. In total, 14 Y. enterocolitica isolates from six slaughterhouses were divided into nine pulsotypes, 13 isolates belonging to biotype 1A or 2 carried only ystB, whereas one isolate belonging to bio-serotype 4/O:3 carried both ail and ystA. This is the first study to investigate microbial quality and the prevalence of foodborne pathogens in carcasses from slaughterhouses nationally, and the findings support the need for ongoing slaughterhouse monitoring to improve the microbiological safety of pig carcasses

Perceived Stress and Frailty in Older Adults

Background Individuals with frailty are susceptible to adverse events. Although a psychological correlation with frailty has been observed, few studies have investigated the relationship between stress and frailty. This study examined the association between perceived stress and frailty in older adults. Methods This cross-sectional observational study included participants recruited between September 2021 and January 2022. The Korean version of the Perceived Stress Scale-10 was used to measure stress levels, while the frailty status was assessed using the Korean Frailty Index. Loneliness, depression, and satisfaction were measured using the UCLA Loneliness Scale, Centre for Epidemiological Studies Depression Scale, and Satisfaction with Life Scale, respectively. We used multinomial logistic regression to compare the variables between frail and robust participants. Results Among 862 study participants (mean age, 73.62 years; 65.5% women), the mean PSS-10 score was 15.26, 10.8% were frail, 22.4% were pre-frail, and 66.8% were robust. Perceived stress was significantly associated with pre-frailty (crude odds ratio [OR]=1.147; 95% confidence interval [CI], 1.093–1.204) and frailty (crude OR=1.417; 95% CI, 1.322–1.520). After adjusting for sociodemographic factors, we examined the associations between perceived stress and prefrailty (adjusted OR=1.140; 95% CI, 1.084–1.199) and frailty (adjusted OR=1.409; 95% CI, 1.308–1.518). After adjusting for all variables, including loneliness, depression, and satisfaction, perceived stress was significantly associated with frailty (adjusted OR=1.172; 95% CI, 1.071–1.283), however, insufficient statistical evidence was observed for pre-frailty (adjusted OR=1.022; 95% CI, 0.961–1.086). Conclusion Higher levels of perceived stress were associated with frailty in older adults. Stress management efforts may help improve frailty in this population

Development of a Mobile Application, “Wild Flowers of Bukhansan National Park (version 1.0)”, for Identification of Plants in Bukhansan National Park

AbstractWe developed the educational purpose mobile application, named “Wild Flowers of Bukhansan National Park (version 1.0)”, aiming for easy identification of wildflowers for students and visitors in the park. When visitors find a flower or part of plant in the park, visitors can search for its name utilizing the pictures and characters provided in their own smartphone mobile devices or tablet PCs. The application provides pictures of wildflowers in the park and character-based searching system based on 12 diagnostic features (e.g., growth form, leaf arrangement, flower symmetry, petal color, petal number, sepal number, etc). We adopted the complete floristic survey of Chung and Lee (1962) and added species that we confirmed their distribution in the park during the development of this application. In summary, number of vascular plants in this park was estimated to be 428 taxa including 100 families, 280 genera, 327 species, 1 subspecies, 50 varieties, and 5 formas. We provided a total of 588 pictures representing 358 taxa and each taxon includes multiple pictures in many cases. Included identification quizzes can be an efficient educational tool as well as fun activity for students and visitors who are learning plant species in Korea. Our next step will include GPS function in the application for indicating visitor's location and for providing previously reported sites of the species that we interested in the map of the park. The future application which includes GPS function will be a valuable tool for the monitoring of rare plants, plant researches related to the climate changes, etc. We currently provide Korean iPhone version only, and English version and both of android versions will be serviced soon

Urinary chiro-and myo-inositol levels as a biological marker for type 2 diabetes mellitus

Abstract. Background: The aim of this study was to investigate the role of the urinary chiro-and myo-inositol levels in predicting type 2 diabetes mellitus (T2DM). Subjects and methods: A total of 212 normal controls and 101 type 2 diabetic patients were enrolled this study. The concentrations of urinary chiro-and myo-inositol were measured by high performance liquid chromatography/mass spectrometry. Results: The concentration of urinary chiro-inositol was significantly higher in the diabetic subjects (2.24 ± 5.18 ng/L) than those in the control group (0.38 ± 0.62 ng/L; p < 0.001). The urinary myo-inositol level of the diabetic subjects (36.95 ± 37.77 ng/L) was also significantly higher than that of the controls (8.17 ± 13.29 ng/L; p < 0.001). The urinary chiro-inositol multiplied by myo-inositol level of the diabetic subjects (148.10 ± 544.91) was significantly higher than in the controls (5.12 ± 24.15; p < 0.001). The area under the receiver operating characteristic curve for the urinary chiro-inositol multiplied by myo-inositol level to predict T2DM was 0.840 (confidence interval 0.789-0.891, p < 0.001). The cut-off value for the urinary chiro-inositol multiplied by myo-inositol level to predict T2DM was 2.20 (sensitivity 81.3%, specificity 70.3%). Conclusions: The urinary chiro-and myo-inositol concentrations were increased in the type 2 diabetic patients and the urinary chiro-times the myo-inositol was considered to be a sufficient marker in predicting T2DM

30 inch Roll-Based Production of High-Quality Graphene Films for Flexible Transparent Electrodes

We report that 30-inch scale multiple roll-to-roll transfer and wet chemical doping considerably enhance the electrical properties of the graphene films grown on roll-type Cu substrates by chemical vapor deposition. The resulting graphene films shows a sheet resistance as low as ~30 Ohm/sq at ~90 % transparency which is superior to commercial transparent electrodes such as indium tin oxides (ITO). The monolayer of graphene shows sheet resistances as low as ~125 Ohm/sq with 97.4% optical transmittance and half-integer quantum Hall effect, indicating the high-quality of these graphene films. As a practical application, we also fabricated a touch screen panel device based on the graphene transparent electrodes, showing extraordinary mechanical and electrical performances