Current-Induced Resonant Motion of a Magnetic Vortex Core: Effect of Nonadiabatic Spin Torque

The current-induced resonant excitation of a magnetic vortex core is investigated by means of analytical and micromagnetic calculations. We find that the radius and the phase shift of the resonant motion are not correctly described by the analytical equations because of the dynamic distortion of a vortex core. In contrast, the initial tilting angle of a vortex core is free from the distortion and determined by the nonadiabaticity of the spin torque. It is insensitive to experimentally uncontrollable current-induced in-plane Oersted field. We propose that a time-resolved imaging of the very initial trajectory of a core is essential to experimentally estimate the nonadiabaticity.Comment: 4 pages, 4 figure

Chronic diseases and others factors that affect suicidal ideation in elderly people

Background: In the elderly, chronic disease and suicide are emerging as serious issues. The purpose of this study was to examine the factors affecting suicidal ideation in elderly people. Methods and materials: This study used raw data from the 2017 Korea Community Health Survey. Of the 228,452 participants in the survey, 64,641 (95.29%) were selected for the study. Those with missing values, no response and outlier values in the initial sample of 67,835 elderly people aged 65 years and above were excluded. The dependent variable was suicidal ideation and the independent variables were related to socio-demographic profiles and chronic disease history. Statistical analyses were performed using logistic regression analysis for factors affecting suicidal ideation. Results: The odds ratio (OR) for suicidal ideation in elderly people was higher in people with a college education than in those with elementary school education or who were illiterate. The OR was higher in people with monthly family incomes of 500,000-1,000,000 won and ≤ 500,000 won, compared to those with monthly incomes of ³ 6,000,000 won. Compared to married elderly people who lived with a spouse, the ORs of divorced and separated people were significantly higher. The ORs of elderly people with diabetes, dyslipidemia, arthritis or cataracts were significantly higher than those of elderly people without chronic diseases. The OR of elderly people with depression was significantly higher than that of elderly people without a history of depression. The primary reason for suicidal ideation was ‘disease or disorder’, and the second was ‘loneliness’. Conclusions: The findings suggest that socio-demographic factors and chronic disease history may be considered risk factors for suicidal ideation. [Ethiop.J. Health Dev. 2020;34(Special issue-3):91-96] Keywords: Suicide, suicidal ideation, aging, elderly, chronic diseas

Seasonal Gradient Patterns of Polycyclic Aromatic Hydrocarbons and Particulate Matter Concentrations near a Highway

Close proximity to roadways has been associated with higher exposure to traffic-related air pollutants. However, analyses of the effects of season and meteorological parameters on horizontal gradient patterns of traffic-generated air pollutants still need to be elucidated. Our objectives were to: (1) determine effects of season on horizontal gradient patterns of polycyclic aromatic hydrocarbons (PAHs), total suspended particles (TSP), and PM2.5 near a heavily trafficked highway; and (2) examine the effect of day-of-the-week variations (weekday versus weekend) associated with traffic counts on measured airborne-contaminant levels. PAHs (Σ8PAHs [MW 228–278]; gas + particulate), TSP and PM2.5 were monitored at nominal distances (50, 100, and 150 m) from the New Jersey Turnpike every 6 days for periods of 24 h, between September 2007 and September 2008. Seasonal variations in the horizontal gradient patterns of Σ8PAHs were observed. In the summer, Σ8PAHs declined significantly between 50–100 m from the highway (23% decrease), but not between the furthermost distances (100–150 m). An inverse pattern was observed in the winter: Σ8PAHs declined between 100–150 m (26% decrease), but not between the closest distances. Σ8PAHs and TSP, but not PM2.5, concentrations measured on weekends were 12–37% lower than those on weekdays, respectively, corresponding to lower diesel traffic volume. This study suggests that people living in the close proximity to highways may be exposed to varying levels of Σ8PAHs, TSP, and PM2.5 depending on distance to highway, season, and day-of-the-week variations

Anti-anxiety effect of methanol extract of Pericarpium zanthoxyli using a strychnine-sensitive glycine receptor model

Purpose: To determine if the methanol extract of Pericarpium zanthoxyli exerts anti-anxiety effects and also to explore any probable anti-anxiety mechanism in vivo.Methods: The staircase test, elevated plus maze test, rota-rod treadmill test and convulsions induced by strychnine and picrotoxin on mice were tested to identify potential mechanism of anti-anxiety activity of the plant extract.Results: The plant extract (10 mg/kg, p.o.) significantly reduced rearing numbers in the staircase test while it increased the time spent in the open arms as well as the number of entries to the open arms in the elevated plus maze test, suggesting that it has significant anti-anxiety activity. Furthermore, the extract inhibited strychnine-induced convulsion. However, it had little effect on picrotoxin-induced convulsion, suggesting that its anti-anxiety activity may be linked to strychnine-sensitive glycine receptor and not GABA receptor.Conclusion: These results suggest that the Pericarpium zanthoxyli extract may be beneficial for the control of anxiety.Keywords: Anti-anxiety, Pericarpium zanthoxyli, Glycine Receptor, GABA Recepto

Inter-Industry Gender Wage Gaps by Knowledge Intensity: Discrimination and Technology in Korea

A new gender wage gap decomposition methodology is introduced that does not suffer from the identification problem caused by unobserved non-discriminatory wage structure. The methodology is used to measure the relative size of Korean gender wage gaps from 1994 to 2000 across industries, differentiated by industrial knowledge intensity, where knowledge intensity is the extent to which industries produce or employ high-technology products. Korea represents an important case study, since it possesses one of the fastest growing knowledge-intensive economies, among industrialized countries. Empirical results indicate that over this period, discrimination (the unexplained portion of the gender wage gaps) in Korea was statistically smaller in knowledge-intensive industries than in industries with low knowledge intensity. Also, discrimination was declining on average over the period. This suggests that continued growth in knowledge-intensive industries in Korea may lead to further declines in the overall gender gap

Scale growth of structures in the turbulent boundary layer with a rod-roughened wall

Direct numerical simulation of a turbulent boundary layer over a rod-roughened wall is performed with a long streamwise domain to examine the streamwise-scale growth mechanism of streamwise velocity fluctuating structures in the presence of two-dimensional (2-D) surface roughness. An instantaneous analysis shows that there is a slightly larger population of long structures with a small helix angle (spanwise inclinations relative to streamwise) and a large spanwise width over the rough-wall compared to that over a smooth-wall. Further inspection of time-evolving instantaneous fields clearly exhibits that adjacent long structures combine to form a longer structure through a spanwise merging process over the rough-wall; moreover, spanwise merging for streamwise scale growth is expected to occur frequently over the rough-wall due to the large spanwise scales generated by the 2-D roughness. Finally, we examine the influence of a large width and a small helix angle of the structures over the rough-wall with regard to spatial two-point correlation. The results show that these factors can increase the streamwise coherence of the structures in a statistical sense.open

Time Dependent Gene Expression Changes in the Liver of Mice Treated with Benzene

Benzene is used as a general purpose solvent. Benzene metabolism starts from phenol and ends with p-benzoquinone and o-benzoquinone. Liver injury inducted by benzene still remains a toxicologic problem. Tumor related genes and immune responsive genes have been studied in patients suffering from benzene exposure. However, gene expression profiles and pathways related to its hepatotoxicity are not known. This study reports the results obtained in the liver of BALB/C mice (SLC, Inc., Japan) administered 0.05 ml/100 g body weight of 2% benzene for six days. Serum, ALT, AST and ALP were determined using automated analyzer (Fuji., Japan). Histopathological observations were made to support gene expression data. c-DNA microarray analyses were performed using Affymetrix Gene-chip system. After six days of benzene exposure, twenty five genes were down regulated whereas nineteen genes were up-regulated. These gene expression changes were found to be related to pathways of biotransformation, detoxification, apoptosis, oxidative stress and cell cycle. It has been shown for the first time that genes corresponding to circadian rhythms are affected by benzene. Results suggest that gene expression profile might serve as potential biomarkers of hepatotoxicity during benzene exposure

The role of social support and social networks in smoking behavior among middle and older aged people in rural areas of South Korea: A cross-sectional study

<p>Abstract</p> <p>Background</p> <p>Although the number of studies on anti-smoking interventions has increased, studies focused on identifying social contextual factors in rural areas are scarce. The purpose of this study was to explore the role of social support and social networks in smoking behavior among middle and older aged people living in rural areas of South Korea.</p> <p>Methods</p> <p>The study employed a cross-sectional design. Participants included 1,057 adults, with a mean age of 60.7 years, residing in rural areas. Information on participants' tobacco use, stress, social support, and social networks was collected using structured questionnaires. The chi-square test, the t-test, ANOVA, and logistic regression were used for data analysis.</p> <p>Results</p> <p>The overall smoking prevalence in the study was 17.4% (men, 38.8%; women, 5.1%). Overall, stress was high among women, and social support was high among men. Smokers had high levels of social support (t = -2.90, p = .0038) and social networks (t = -2.22, p = .0271), as compared to non- and former smokers. Those in the high social support group were likely to be smokers (AOR = 2.21, 95% CI 1.15-4.26). Women with moderate social ties were less likely to smoke (AOR = 0.18, 95% CI 0.05-0.61).</p> <p>Conclusion</p> <p>There was a protective role of a moderate social network level among women, and a high level of social support was associated with smoking behaviors in rural areas. Findings suggest the need for a comprehensive understanding of the functions and characteristics of social contextual factors including social support and social networks in order to conduct more effective anti-smoking interventions in rural areas.</p