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In this study, a hydraulic analysis technique is presented for evaluating the efficiency of a pool-weir type fishway. The River-2D model with the fish physical habitat module was used for the analysis of the attraction efficiency, and the weighted usable area proposed as an index of the efficiency. For the analysis of passage efficiency, the three-dimensional model, FLOW-3D, was used as an evaluating tool to describe the fluid behavior on a hydraulic structure with a free surface. The ice-harbor type fishway at Dalseong weir in the Nakdong River of Korea was selected as a test-site, and the efficiency was estimated using the hydraulic analysis. The results of River-2D analysis showed that the location of the fishway near the right bank now was not appropriate for attracting the target fish to the fishway due to the deep water depth. The 3D analysis results presented that the flow velocity field inside the fishway showed a similar plunging flow in each pool, but various flow patterns appeared locally.

Nuclear factor of activated T cells 5 (NFAT5) has been implicated in the pathogenesis of various human diseases, including cancer and arthritis. However, therapeutic agents inhibiting NFAT5 activity are currently unavailable. To discover NFAT5 inhibitors, a library of >40,000 chemicals was screened for the suppression of nitric oxide, a direct target regulated by NFAT5 activity, through high-throughput screening. We validated the anti-NFAT5 activity of 198 primary hit compounds using an NFAT5-dependent reporter assay and identified the novel NFAT5 suppressor KRN2, 13-(2-fluoro)-benzylberberine, and its derivative KRN5. KRN2 inhibited NFAT5 upregulation in macrophages stimulated with lipopolysaccharide and repressed the formation of NF-κB p65-DNA complexes in the NFAT5 promoter region. Interestingly, KRN2 selectively suppressed the expression of pro-inflammatory genes, including Nos2 and Il6, without hampering high-salt-induced NFAT5 and its target gene expressions. Moreover, KRN2 and KRN5, the latter of which exhibits high oral bioavailability and metabolic stability, ameliorated experimentally induced arthritis in mice without serious adverse effects, decreasing pro-inflammatory cytokine production. Particularly, orally administered KRN5 was stronger in suppressing arthritis than methotrexate, a commonly used anti-rheumatic drug, displaying better potency and safety than its original compound, berberine. Therefore, KRN2 and KRN5 can be potential therapeutic agents in the treatment of chronic arthritis.

To improve healing of pressure ulcer wounds, it is important to optimize the conditions of the area surrounding the wound. Negative pressure wound therapy (NPWT) promotes wound healing, however, the removal of NPWT can cause pain or focal bleeding, delaying wound healing or causing infection. In this study, we reviewed the efficacy of the lipidocolloid non-adherent dressing (Urgotul®) as a wound contact layer. A total of 38 patients from the same facility who applied NPWT from April 2016 to October 2019 were included and divided into two groups; NPWT with the lipidocolloid non-adherent dressing (group 1, experimental group, 19 patients) and NPWT only (group 2, control group, 19 patients). The condition of the wound was examined prior to NPWT application, at one week, and again at three weeks after application. No significant differences were found between groups for general characteristics, bacterial culture or photo analysis. However, when comparing groups based on the time of examination, there was a significant reduction of the wound size in group 1 (p = 0.001) but not in group 2 (p = 0.082). Therefore, the current study finds that using the lipidocolloid non-adherent dressing as a wound contact layer in NPWT stimulates healing by shrinking the size of the pressure ulcer wound.

Governments and also local councils create and enforce their own regional public health care plans for the problem of overweight and obesity in the population. Public sports facilities can help these plans. In this paper, we investigated the contribution of public sports facilities to the reduction of the obesity of local residents. We used the data obtained from the Fifth Korea National Health and Nutrition Examination Surveys; and measured the degree of obesity using body mass index (BMI). We conducted various spatial regression analyses including the global Moran’s I test and local indicators of spatial autocorrelation analysis finding that there exists spatial dependence in the error term of spatial regression model for BMI. However, we also observed that the number of local public sports facilities is not significantly related to local BMI. This result can be caused by the low utilization ratio and an unbalanced spatial distribution of local public sports facilities. Based on our findings, we suggest that local councils need to improve the quality of public sports facilities encouraging the establishment of preferred types of pubic sports facilities.

Several new varieties of airbags are under consideration for development. However, their commercialization decision must be backed by a positive Cost-Benefit Analysis (CBA) outcome. In this study, we propose a CBA framework for the frontal center curtain airbag, a newly designed safety system intended to reduce the injury risk of rear-seat passengers. The proposed CBA covers not only economic benefits of the producer but also the effectiveness in sustainable reduction of the fatal and injury rate. In this context, with accumulated field data on road traffic accidents, a forecasting method reflecting the reduced casualties and the market share of vehicle sales associated with frontal center curtain airbag is utilized. Our results suggest that the use of frontal center curtain airbags helps to reduce the number of casualties with a Maximum Abbreviated Injury Scale (MAIS) of 3 or above by 87.4%. Furthermore, both the initial market penetration rate and price of the frontal center curtain airbag significantly influence its socioeconomic benefits. By evaluating the effectiveness of the frontal center curtain airbag, our study can contribute to the decision making for its commercialization. [ABSTRACT FROM AUTHOR]

Tracer tests were conducted using floaters equipped with a global positioning system (GPS) to investigate the turbulent mixing of the floating pollutant at the surface of natural rivers. The position data were collected by tracking the floaters at different reaches of the Nakdong River in Korea, and the diffusion coefficients were calculated by applying the moment method to the floater distribution data collected. While applying the moment method, the diffusion coefficient was calculated from the time evolution of variance of the particle distribution, which becomes the distance from the centroid of the particle cloud, based on the homogeneous turbulence assumption and the ergodic hypothesis of the turbulent mixing. Analysis of the trajectories of GPS floaters showed that the horizontal mixing in the initial mixing stage was hampered by the interaction and collision between floaters. The experimental results revealed that the dimensionless streamwise diffusion coefficients were larger, in the range of 0.11-0.56, while the spanwise component was in the range of 0.02-0.16. The simulation results using the Lagrangian particle tracking model of the Environmental Fluid Dynamics Code program showed that the discrepancy between the predicted values and the observed data in the initial time gradually decreased as time elapsed. [ABSTRACT FROM AUTHOR]

While patents do have many advantages, their disadvantages include requiring disclosure of technical information and imposing the burden of patenting and litigation costs. In this study, we investigate the relationship between a firm's negative perception on patents, technology management strategies, and subsequent performance. For this purpose, we use a categorical canonical correlation analysis of the top 200, large, R&D-intensive firms in Korea. We find that negative perceptions such as burdensome transaction costs, non-patenting culture, and uncertainty of the outcome of patent litigation are associated with firms' technology management strategies, such as purchase of licenses, and subsequent performance, such as an increase in the number of inventions from the cross-fertilization of different technologies. The results of this study are expected to contribute to a better understanding of firms' negative attitudes toward the effects of patents, their subsequent technology management strategies, and resulting performance. [ABSTRACT FROM AUTHOR]

Makers of heavy-duty diesel engines (HDDEs) need to reduce their inventory of old-generation products in preparation for the demand for next-generation products that satisfy new emission regulations. In this paper, a new demand forecasting model is proposed to reflect special conditions raised by the technological generational shift owing to new emission regulation enforcement. In addition, sensitivity analyses are conducted to better accommodate uncertainty involved at the time of prediction. Our proposed model can help support manufacturers' production and sales management for a series of products in response to new emission regulations. [ABSTRACT FROM AUTHOR]

One of the main missions of Microfinance Institutions is to improve the status of under-privileged people. However, MFI's mission drift or enhancement can occur under adverse economic condition. In this paper, we investigate the direction of changes in supporting women borrowers who make up the majority of the poor by using the lending patterns of Latin American and Caribbean MFIs during the recent global financial crisis. P control chart is applied to detect assignable changes in the lending rate to woman over different MFIs. In order to identify related characteristics to the outlying MFIs identified from the P control chart, we perform logistic regression analysis. Our study results can contribute to understand MFI's mission change in terms of supporting women borrowers and identify the related characteristics of MFIs. [ABSTRACT FROM AUTHOR]

To investigate the two-dimensional dispersion characteristics of the dissolved contaminant in natural rivers, tracer experiments were performed based on the instantaneous injection of Rhodamine WT solution into small- to medium-sized rivers in Korea. The relations between the dispersion coefficients and hydraulic and geometric variables of the river were analyzed in depth. The experimental results show that transverse dispersion coefficient tends to increase as the friction term, U/U*, and the channel aspect ratio,W/H, increase. The effect of the channel curvature on the rate of transverse mixing was found to be very distinct in that DT/HU* has a linear relation with UW/U*Rc, even though the slope of the fitted line in the plot of DT/HU* versus UW/U*Rc in a log-log scale was much smaller than the slope of the equation by Yotsukura and Sayre. The longitudinal dispersion coefficient also tends to increase as U/U* and W/H increase. However, DL is rather insensitive to the channel curvature. The values of the longitudinal dispersion coefficient from field studies are much higher than the theoretical value suggested by Elder. The observed longitudinal dispersion coefficient is one order of magnitude larger than Elder's coefficient, and DL/DT of this study ranges 26.6-332. [ABSTRACT FROM AUTHOR]

A particle-tracking experiment using surface floats was conducted to better understand the characteristics of a floating pollutant mixture in meandering channels. The experiments were performed in a life-size scale experiment center that can replicate natural flow structures. The experimental flume includes sinuosities of 1.2, 1.5, and 1.7. Surface mixing was analyzed with respect to these sinuosity values. The surface float was designed to represent the mixing by surface flow. The trajectories of the floats were recorded by built-in GPS. From the positions of the GPS floaters, the longitudinal and transverse diffusion coefficients were calculated using the moment method. The results of the calculations show that the dimensionless longitudinal diffusion coefficient ranges from 5.94 to 14.55 and the dimensionless transverse diffusion coefficient ranges from 0.37 to 2.61. These results suggest that the mixing of floating pollutants has directional properties in the meandering channels due to shear flow. Furthermore, the relationship between the longitudinal diffusion coefficient and the integral timescale was found to have a linear relationship in accordance with Taylor's theory. [ABSTRACT FROM AUTHOR]

Background: We investigated the association between the severity of non-alcoholic fatty liver disease (NAFLD) and the estimated 10-year risk of cardiovascular disease (CVD) calculated by Pooled Cohort Equation (PCE) and Framingham risk score (FRS). Methods: A total of 15,913 participants (mean age, 46.3 years) in a health screening program were selected for analysis. The presence and severity of fatty liver was assessed by abdominal ultrasonogram. Subjects who drank alcohol more than three times a week were excluded from the study. Results: Among the participants, 57.6% had no NAFLD, 35.4% had grade I, 6.5% had grade II, and 0.5% had grade III NAFLD. Mean estimated 10-year CVD risk was 2.59%, 3.93%, 4.68%, and 5.23% calculated using the PCE (P for trend <0.01) and 4.55%, 6.39%, 7.33%, and 7.13% calculated using FRS, according to NAFLD severity from none to severe (P for trend <0.01). The odds ratio for ≥7.5% estimated CVD risk calculated using the PCE showed a higher correlation with increasing severity of NAFLD even after adjustment for conventional CVD risk factors (1.52, 2.56, 3.35 vs. the no NAFLD group as a reference, P<0.01) compared with calculated risk using FRS (1.65, 1.62, 1.72 vs. no NAFLD group as a reference, P<0.01). Conclusion: In our study of apparently healthy Korean adults, increasing severity of NAFLD showed a higher correlation with estimated 10-year CVD risk when calculated using the PCE than when calculated using FRS. [ABSTRACT FROM AUTHOR]

Background/Context: Research on Chinese immigrant parents tends to focus on their high levels of educational involvement and its positive impact on their children's exceptional educational performances. Relatively little research has been conducted to understand the challenges Chinese immigrant parents face in helping their children with school and the resulting influence on parent-child relations and children's adaptation. Focus of Study: In this paper, we examined how immigration reshapes parental involvement in these Chinese immigrant families and its subsequent influence on parent-child relations. Setting: The research was conducted in the metropolitan area of a northeastern city in the United States. Participants: Our participants were 72 Chinese immigrant children and their parents. Research Design: Our study utilizes longitudinal interview data with open-ended questions. Open, axial, and selective coding procedures were used in qualitative data analysis. Findings/Results: Our findings suggest that when parents face multiple challenges in their adaptation after migration, they often experience a feeling of powerlessness especially in dealing with their children's schooling. This then forces the children to be precociously independent. This dynamic puts strain on parent-child relations and has a negative impact on children's adaptation. Conclusions/Recommendations: It is important for schools and other social institutions working with Chinese immigrant families to reach out to parents by providing them with more information and resources to be more involved in their children's education. Immigrant and local communities can also help by offering parent and youth programs to help improve parental involvement and parent-child relations in Chinese and other immigrant families. [ABSTRACT FROM AUTHOR]

Gonadotropin-releasing hormone (GnRH) agonist has been used in the treatment of a wide variety of sex-hormone-related diseases, as the administration of GnRH agonist can alter the secretion of gonadotropin and sex hormones. Recently, we found that the long-acting GnRH agonist aggravated hyperthyroidism and induced painless thyroiditis. This is the first report to demonstrate the association of thyroid dysfunction with GnRH agonist injection in Korea. Here, we report three cases and emphasize the clinical importance of this aggravating factor in autoimmune thyroid disease. [ABSTRACT FROM AUTHOR]