• Economic Analysis
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• v.17 no.4
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• pp.30-51
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• 2011

Since the previous studies on the effects of trade liberalization implicitly assume that trade liberalization affects economic performance only in any point in time, they inevitably are static. Static evaluations fail to account for cumulative dynamic effects of trade liberalization that affect continuously economic performance. This paper tries to fill this gap of the previous studies in this field, estimating cumulative effects of trade liberalization on economic performance by employing an dynamic version of empirical model. One of important empirical issue is controlling bias from endogeneity. To resolve this problem, this paper employes system GMM that uses lagged first-differences as instruments for level equations and lagged levels as instruments for first-differences equations. It improves upon cross-section estimators because it controls for the potential bias induced by the omission of industry-specific effects and the endogeneity of all regressors. This study investigates the effects of trade liberalization in Korean manufacturing for the period from 1988 to 2005 and finds that cumulative dynamic effects of trade liberalization are present and bigger than static effects.

• Journal of Microbiology and Biotechnology
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• v.33 no.8
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• pp.1091-1100
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• 2023

Human papillomavirus (HPV) types 16 and 18 are the major causes of cervical lesions and are associated with 71% of cervical cancer cases globally. However, public health infrastructures to support cervical cancer screening may be unavailable to women in low-resource areas. Therefore, sensitive, convenient, and cost-efficient diagnostic methods are required for the detection of HPV16/18. Here, we designed two novel methods, real-time ERA and ERA-LFD, based on enzymatic recombinase amplification (ERA) for quick point-of-care identification of the HPV E6/E7 genes. The entire detection process could be completed within 25 min at a constant low temperature (35-43℃), and the results of the combined methods could be present as the amplification curves or the bands presented on dipsticks and directly interpreted with the naked eye. The ERA assays evaluated using standard plasmids carrying the E6/E7 genes and clinical samples exhibited excellent specificity, as no cross-reaction with other common HPV types was observed. The detection limits of our ERA assays were 10⁰ and 10¹ copies/µl for HPV16 and 18 respectively, which were comparable to those of the real-time PCR assay. Assessment of the clinical performance of the ERA assays using 114 cervical tissue samples demonstrated that they are highly consistent with real-time PCR, the gold standard for HPV detection. This study demonstrated that ERA-based assays possess excellent sensitivity, specificity, and repeatability for HPV16 and HPV18 detection with great potential to become robust diagnostic tools in local hospitals and field studies.

• Korean Medical Education Review
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• v.25 no.3
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• pp.243-257
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• 2023

This study aimed to analyze trends in research on depression among medical students in Korea and to conduct a meta-analysis to determine the average correlation coefficients between depression and related variables. In total, 38 quantitative studies (four theses and 34 journal articles) published between January 1995 and February 2023 were analyzed according to publication year, subjects, analysis methods, and measurement tools. Among them, 15 studies that provided numerical information on the relationships between depression and variables such as self-esteem, social support, grade point average (GPA), stress, and academic stress were selected for meta-analysis. The main findings of this study were as follows. First, quantitative research on depression among medical students began in earnest in 2009, and cross-sectional studies targeting first-year and second-year medical students were the most prevalent. Furthermore, the most commonly used analysis method was difference testing, and the Beck Depression Inventory was the most frequently used measurement tool. Second, the mean correlation coefficients between depression and stress, self-esteem, social support, academic stress, and GPA were 0.534, 0.532, 0.465, 0.390, and 0.102, respectively. The results for self-esteem, stress, and academic stress showed substantial heterogeneity, while those for social support and GPA showed little heterogeneity. These findings suggest that educational interventions, such as social support improvement programs, are necessary to prevent depression among medical students.

• Journal of Korean Academy of Nursing
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• v.53 no.6
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• pp.571-583
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• 2023

Purpose: This study used a self-deterministic approach to explore the relationship between emotional intelligence (EI), academic motivation (AM), and achievement among health science students. Methods: A descriptive cross-sectional study was conducted in three cities of Saudi Arabia (Dammam, Riyadh, and Jeddah). A convenience sample of 450 students was incorporated using the multistage cluster sampling technique. The online survey contained three sections: students' basic data and academic achievement level, the modified Schutte self-report inventory, and the Academic Motivation Scale lowercase. Results: This study revealed moderate overall scores for EI (57.1%), AM (55.6%), and grade point average (GPA) (57.6%). The overall EI score, its domains, and GPA had significant positive correlations with overall AM and intrinsic and extrinsic motivation (p < .01). Amotivation had an insignificant correlation with GPA (p < .05), but it was negatively correlated with EI and its domains (p < .01). Multiple regression analysis proved that EI domains predicted 5.0% of GPA variance; emotions appraisal and expression (β = .02, p = .024), regulation (β = .11, p = .032), and utilization (β = .24, p < .01). EI domains also predicted 26.0% of AM variance; emotions appraisal and expression (β = .11, p = .04), regulation (β = .33, p < .01), and utilization (β = .23, p < .01). Moreover, AM predicted 4.0% of the variance in GPA; intrinsic (β = .25, p = .004) and extrinsic (β = .11, p = .022) motivation. AM also predicted 25.0% of the variance in EI: intrinsic (β = .34, p < .01) and extrinsic motivation (β = .26, p = .026). Conclusion: EI and AM have a bidirectional influence on each other, significantly shaping the GPA of health sciences students in Saudi Arabia, where intrinsic motivation has a predominant role. Thus, promoting students' AM and EI is recommended to foster their academic achievement.

• Korean Journal of Materials Research
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• v.34 no.2
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• pp.111-115
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• 2024

Silicon carbide (SiC) has emerged as a promising material for next-generation power semiconductor materials, due to its high thermal conductivity and high critical electric field (~3 MV/cm) with a wide bandgap of 3.3 eV. This permits SiC devices to operate at lower on-resistance and higher breakdown voltage. However, to improve device performance, advanced research is still needed to reduce point defects in the SiC epitaxial layer. This work investigated the electrical characteristics and defect properties using DLTS analysis. Four deep level defects generated by the implantation process and during epitaxial layer growth were detected. Trap parameters such as energy level, capture-cross section, trap density were obtained from an Arrhenius plot. To investigate the impact of defects on the device, a 2D TCAD simulation was conducted using the same device structure, and the extracted defect parameters were added to confirm electrical characteristics. The degradation of device performance such as an increase in on-resistance by adding trap parameters was confirmed.

• Clinics in Shoulder and Elbow
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• v.27 no.1
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• pp.45-51
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• 2024

Background: It is essential to distinguish between symptomatic- and asymptomatic radiographic acromioclavicular (AC) osteoarthritis (OA) because AC-targeted physical examinations are dubious. This study aimed to determine the diagnostic value of a preoperative AC injection in discriminating between symptomatic- and asymptomatic radiographic AC OA based on patient arthroscopic distal clavicle resection (aDCR) outcomes. Methods: Forty-eight patients who underwent aDCR for AC OA were included. Their satisfaction was objectified using a 5-point Likert scale and patient willingness to repeat the surgery. The Oxford Shoulder Score (OSS), the Subjective Shoulder Value (SSV), and the Numerical Rating Scale (NRS) were used to assess postoperative shoulder function and pain. Patients were subdivided into groups based on their good or minimal reaction to an AC injection (good reaction: ≥7 consecutive days of pain reduction, Minimal reaction: <7 consecutive days of pain reduction). Results: Twenty-seven patients had a good reaction and 21 patients had a minimal reaction to the AC injection (median follow-up, 45.0 months; range, 31.0-52.8 months). No significant differences were found in level of satisfaction (P=0.234) or willingness to repeat the surgery (P=0.861). No significant differences were found in OSS (P=0.612), SSV (P=0.641), NRS at rest (P=0.684) or during activity (P=0.422). Conclusions: This study found no significant differences between patients with a good reaction or a minimal reaction to an AC injection after aDCR surgery. The outcomes of this study seem to suggest that a distinction between symptomatic and asymptomatic radiographic AC OA is unnecessary, as all patients were equally satisfied with the outcome.

• Journal of Preventive Medicine and Public Health
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• v.57 no.3
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• pp.223-233
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• 2024

Objectives: The coronavirus disease 2019 pandemic has exacerbated the rate of tuberculosis (TB) infection among close contacts of TB patients in remote regions. However, research on preventive behaviors, guided by the Health Belief Model (HBM), among household contacts of TB cases is scarce. This study aimed to employ the HBM as a framework to predict TB preventive behaviors among household contacts of TB patients in the border areas of Northern Thailand. Methods: A cross-sectional study with multi-stage random sampling was conducted in Chiang Rai Province. The study included 422 TB patients' household contacts aged 18 years or older who had available chest X-ray (CXR) results. A self-administered questionnaire was used to conduct the survey. Results: The participants' mean age was 42.93 years. Pearson correlation analysis showed that TB preventive behavior scores were significantly correlated with TB knowledge (r=0.397), perceived susceptibility (r=0.565), perceived severity (r=0.452), perceived benefits (r=0.581), self-efficacy (r=0.526), and cues to action (r=0.179). Binary logistic regression revealed that the modeled odds of having an abnormal CXR decreased by 30.0% for each 1-point score increase in preventive behavior (odds ratio, 0.70; 95% confidence interval, 0.61 to 0.79). Conclusions: HBM constructs were able to explain preventive behaviors among TB patients' household contacts. The HBM could be used in health promotion programs to improve TB preventive behaviors and avoid negative outcomes.

• Atmosphere
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• v.34 no.4
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• pp.397-415
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• 2024

Reported tornado event occurred in Dangjin, Chungcheongnam-do at 0650~0730 UTC on 15 March 2019 was examined using Weather Research and Forecasting model with four nested domains (dx = 5, 1, 0.2, and 0.05 km). From synoptic analysis in ERA5 reanalysis data, eastward moving upper-level trough was developed rapidly in the Yellow Sea. Strong tropopause folding with Potential Vorticity Unit (PVU) higher than 1.5 PVU moved downward to 600-hPa level in mid troposphere following the trough over the location of tornado event. Under this large-scale background condition, surface front developed very intensively in the west coast of Korea along with strong low-level jet and moisture band at 850-hPa level. In domain 2, the maximum Bulk wind shear at Dorido point was 12.86 m s^-1. Cold front evolved to be a comma cloud with upper-level trough and strong bulk vertical shear near Dangjin, which include eastward moving gust front revealed as a strong horizontal temperature gradient and convergence near the surface. In domains 3 and 4, the local maximum value of the simulated vertical vorticity (24 × 10^-2 s^-1) with strong updraft (8.18 m s^-1) near the observed tornado event along with the surface gust front was found to be a possible area for tornadogenesis from the x-z and time-z cross-sections near the simulated tornado event. In the vorticity budget analysis, the local maximum of vertical vorticity during this event was generated significantly by tilting and stretching forcings.

• Journal of Ocean Engineering and Technology
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• v.38 no.4
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• pp.164-173
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• 2024

In this study, a submerged breakwater with effective wave control and eco-friendly characteristics is developed and proposed. Hydraulic experiments are conducted to compare the hydraulic performance of a submerged breakwater and an eco-friendly double-row submerged breakwater. The hydraulic characteristics are analyzed based on wave reflections and the transmission-splitting method for each experimental cross-section. This splitting technique utilizes Goda's two-point method, which employs the spectra of two irregular superposed wave fields. In addition, the reliability of the results obtained from the hydraulic experiments is discussed by comparing the results with empirical formulas. The eco-friendly double-row submerged breakwater features approximately half the width of a typical submerged breakwater. Nevertheless, its transmission coefficient (K_T) is approximately 20% more effective, and the difference in the average reflection coefficient (K_R) values between the two is approximately 0.17. Moreover, the dissipation coefficient (K_D) shows a generally similar trend. Based on these experimental results, the hydraulic performance of the eco-friendly double-row submerged breakwater is more efficient regarding wave control, compared with a typical submerged breakwater. These hydraulic characteristics confirm that the numerical model developed for the eco-friendly double-row submerged breakwater accurately reproduces the K_T, K_R, and K_D values within ±5%.

• Anatomy and Cell Biology
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• v.55 no.2
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• pp.161-169
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• 2022

Palmar creases are unique, permanent, and genetically controlled morphological variables. Recognizing palmar crease types are important for personal identification, criminal investigations, and diagnosis of congenital diseases. This study aimed to reveal the anthropological characteristics as well as contribute to the diagnosing of congenital disease of Ethiopian people. In this study, a cross-sectional study design with a multistage sampling technique were used. Chi-square test, bivariable, and multivariable multinomial logistic regression models were employed. At bivariable analysis variables with a P-value of ≤0.2 were selected for multivariable analysis and at multivariable analysis variables with a P-value of ≤0.05 were considered as statistically significant factors. Most of study participants had normal palmar crease patterns (90.8%), followed by simian crease patterns (5.0%), whereas sydney crease patterns was the least (1.92%). Being male was more likely to have simian crease and sydney crease than normal crease. Right-handed subjects were less likely to have simian crease and suwon crease than normal crease. The simian crease was more common among students whose fathers were from Gurage ethnicity than normal creases. Students who have one point of origin of the primary palmar creases were more likely to have simian crease, sydney crease, and suwon crease than normal crease. In this study, the normal type of palmar crease patterns was the most prevalent. Whereas the simian crease pattern was the commonest type among the variant palmar creases. Palmar crease patterns are affected by sex, ethnicity, handedness, and points of origin of the primary palmar crease.