• Horticulture, Environment, and Biotechnology : HEB
• /
• v.59 no.6
• /
• pp.815-826
• /
• 2018

The intense drought affecting olive production in Northern Chile underscores the need to research non-traditional irrigation strategies to obtain the best crop performance. Accordingly, this study aimed to obtain preliminary data to guide future research on this topic. Different water replenishment levels on crop evapotranspiration ($ET_c$ ; 13.5, 27.0, 40.5, and 54%) were established in a young orchard, cv. Arbequina, from the end of fruit drop (EFD) to full bloom in the next season. We evaluated the influence of plant water status (${\Psi}_{stem}$ ) and crop load, considered as function of fruit number divided by trunk cross-sectional area, on reproductive and productive variables using multiple linear regressions. Our results show that crop load and ${\Psi}_{stem}$ measured from EFD to harvest affected yield components. Nevertheless, ${\Psi}_{stem}$ had the strongest influence on fruit size, pulp development, oil accumulation, and yield. Oil content and yield were reduced by 54% and 50% for each MPa, respectively, from ${\Psi}_{stem\;EFD-H}$ -1.8 MPa, an effect that intensified as crop load increased. During the period of flower development (September-November), the number of flowers per inflorescence and percentage of perfect flowers were reduced when ${\Psi}_{stem}$ was less than -2.0 MPa. These preliminary results showed that bud differentiation, inflorescence and flower formation are highly sensitive to water deficit.

• Korean Journal of Clinical Pharmacy
• /
• v.28 no.4
• /
• pp.308-319
• /
• 2018

Background: Some mental illnesses such as depression are known to be one of the risk factors of suicide and proper antidepressant therapy can reduce suicidal behavior. Objectives: This study aimed to analyze regional variations in antidepressant consumption and adherence, suicide rate, prevalence of suicide related mental disorders, and access to relevant healthcare services. Methods: Cross-sectional analyses were conducted using National Patients Sample data compiled by the Health Insurance Review and Assessment Service between 2014 and 2016. We included patients who had a diagnosis record of suicide related mental disorders during the study period. Cause of death statistics and National health and medical statistics were used to identify suicide rate and distribution of healthcare service. We conducted visual analyses, chi-squared tests, independent t-tests and correlation analyses to demonstrate regional variations. Results: Between 2014 and 2016, the average prevalence of suicide related mental disorders was 5.4 per cent. Suicide rate and prevalence of suicide related mental disorders were higher in Gangwon, Chungcheong, and Jeolla (p < 0.001), and lower in Seoul (p < 0.001) than the national average. Unexpectedly, regional variations in antidepressant consumption were seen in the limited area including Daejeon, Chungnam and Gyeongnam (p < 0.05). The number of mild patient-centered clinics was associated positively with antidepressant consumption (p < 0.01) and associated negatively with suicide rate (p < 0.01). Conclusion: There were some regional variations in prevalence of suicide related mental disorders, antidepressant adherence and suicide rate. The higher level of antidepressant therapy and the lower level of suicide rates were seen in regions with easy access to mild patient-centered clinics.

• Journal of Yeungnam Medical Science
• /
• v.36 no.2
• /
• pp.141-147
• /
• 2019

Background: The present study aimed to evaluate the clinical association between cadmium exposure and hearing impairment among the Korean population. Methods: This retrospective cross-sectional study used the data obtained from the Korean National Health and Nutrition Examination Survey were used for our study. Finally, 3,228 participants were included in our study, which were then divided into quartiles based on their blood cadmium levels: first quartile (1Q), second quartile (2Q), third quartile (3Q), and fourth quartile (4Q) groups. The hearing thresholds were measured using an automatic audiometer at 0.5, 1, 2, 3, 4, and 6 kHz. Hearing loss (HL) was defined as >25 dB average hearing threshold (AHT). Results: All the groups had 807 participants each. The area under the receiver operating characteristic curves of cadmium level for HL were 0.634 (95% confidence interval [CI], 0.621-0.646). The participants in the 4Q group had higher Low/Mid-Freq, High-Freq, and AHT values than those in the other groups in the multivariate analysis after adjusting for confounding factors. The logistic regression showed that the OR for HL per $1{\mu}g/L$ increase in cadmium was 1.25 (95% CI, 1.09-1.44; p=0.002) on the multivariate analysis. Moreover, the multivariate logistic regression analyses revealed that the participants in the 4Q group exhibited a 1.59-, 1.38-, and 1.41-fold higher odds for HL than those in the 1Q, 2Q, and 3Q groups, respectively. Conclusion: High cadmium level quartile was associated with increased hearing thresholds and HL among the Korean adult population.

• Clinical and Experimental Pediatrics
• /
• v.62 no.6
• /
• pp.240-243
• /
• 2019

Purpose: Coronary arterial lesion assessment in children can be difficult, depending on the coronary dominance pattern. Although it is easier to determine coronary dominance with echocardiography in children than in adults, it is still difficult. This study aimed to examine the coronary dominance pattern according to the objective coronary artery (CA) indices. Methods: The CA diameter, aortic valve annulus, and abdominal aorta of 69 children without any cardiovascular disease were measured with cross-sectional echocardiography at Chungnam National University Hospital. To evaluate the coronary dominance pattern, echocardiography was primarily used; additionally, coronary computed tomographic angiography or coronary angiography (CAG). Coronary dominance was determined according to the status of the CA that gives rise to the posterior descending artery. Results: The mean age was $4.02{\pm}2.78years$, and the mean body surface area (BSA) was $0.70{\pm}0.22m^2$. Right dominance was present in 78% and left in 22% of the subjects. In those with left dominance, the CA to aortic valve annulus diameter ratio was $0.125{\pm}0.021$ in the right coronary artery (RCA) and $0.255{\pm}0.032$ in the left coronary artery (LCA). In those with right dominance, the corresponding ratio was $0.168{\pm}0.028$ in the RCA and $0.216{\pm}0.030$ in the LCA (P<0.05). Significant differences were also found in the diametric ratios of the CA to BSA and abdominal aorta (P<0.05). Conclusion: The CA indices showed significant difference according to the coronary dominance pattern in early childhood. It is possible to indirectly determine the coronary dominance pattern with the CA indices in children using echocardiography. The accuracy of coronary artery lesion diagnosis can be improved by taking coronary dominance into account.

• Clinical and Experimental Pediatrics
• /
• v.62 no.7
• /
• pp.261-268
• /
• 2019

Purpose: This study aimed to evaluate the time trends of waist circumference (WC) and waist-height ratio (WHR), and to present WC and WHR distributions with optimal WHR cutoff for abdominal obesity in Korean children and adolescents. Methods: We performed a retrospective cross-sectional analysis of data from 13,257 children and adolescents (6,987 boys and 6,270 girls) aged 6-18 years who were included in the third to sixth Korea National Health and Nutrition Examination Survey (KNHANES, 2005-2015). Linear regression analyses were used to identify secular changes in WC and WHR by age, sex, and KNHANES waves. A receiver operating characteristic curve analysis was used to determine the optimal WHR cutoff values for abdominal obesity and cardiometabolic risk factors. Results: The mean WC and WHR distributions from 2005 to 2015 showed no significant secular changes between the KNHANES 4 waves (P for trend ${\geq}0.05$ in all ages and both sexes). The mean WCs in the present study were lower than those in the 2007 Korean National Growth Charts. The mean WHR at ages <13 years was statistically higher in the boys than in the girls, but did not significantly differ between the sexes among those aged 13 to 18 years. The optimal WHR cutoff for abdominal obesity was 0.48 (area under the curve, 0.985; 95% confidence interval, 0.985-0.985) in the 13- to 18-year-old adolescents. Conclusion: WC and WHR showed no secular changes over 10 years. The optimal WHR cutoff for abdominal obesity of 0.48 is useful for diagnosing and managing obesity and thus preventing obesity-related cardiometabolic complications in 13- to 18-year-old Korean adolescents.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.22 no.4
• /
• pp.492-500
• /
• 2019

Equal channel angular pressing(ECAP) is a severe plastic deformation technique capable of introducing large shear strain in bulk metal materials. However, if an ECAPed material has an inhomogeneous microstructure and anisotropic mechanical properties, this material is difficult to apply as structural components subjected to multi-axial stress during use. In this study, extruded oxygen-free copper(OFC) rods with a large diameter of 42 mm are extruded through ECAP by route Bc up to 12 passes. The variations in the microstructure, hardness, tensile properties, and microstructural and mechanical homogeneity of the ECAPed samples are systematically analyzed. High-strength OFC rods with a homogeneous and equiaxed-ultrafine grain structure are obtained by the repeated application of ECAP up to 8 and 12 passes. ECAPed samples with 4 and 8 passes exhibit much smaller differences in terms of the average grain sizes on the cross-sectional area and the tensile strengths along the axial and circumferential directions, as compared to the samples with 1 and 2 passes. Therefore, it is considered that the OFC materials, which are fabricated via the ECAP process with pass numbers of a multiple of 4, are suitable to be applied as high-strength structural parts used under multi-axial stress conditions.

• Journal of the Korean GEO-environmental Society
• /
• v.20 no.3
• /
• pp.31-38
• /
• 2019

To determine the optimum dynamic load test analysis for PCFT (Prestressed Concrete Filled steel Tube) hybrid composite piles that PCFT piles are connected to the top of PHC piles, the dynamic load tests and CAPWAP analyses were performed on two hybrid composite piles with steel pipe and PCFT piles as upper piles. The results of the dynamic load tests and CAPWAP analyses showed that the particle velocity measured in PCFT hybrid composite piles was equal to the wave speed of PHC piles when the strain gauges and accelerometers are attached to the surface of inner composite PHC pile after removing the steel pipe in the upper PCFT pile. In addition, when assuming that the material of that upper PCFT pile was the same as that of the lower PHC pile and the cross-sectional area of the steel pipe in upper PCFT pile was converted to that for concrete through the pile model (PM) in CAPWAP analysis, the accuracy of the CAPWAP analysis result for PCFT hybrid composite piles was very high.

• Journal of Sensor Science and Technology
• /
• v.28 no.3
• /
• pp.198-204
• /
• 2019

In this study, we propose a wearable force sensor using 3D printed mold and liquid metal. Liquid metal, such as Galinstan, is one of the promising functional materials in stretchable electronics known for its intrinsic mechanical and electronic properties. The proposed soft force sensor measures the external force by the resistance change caused by the cross-sectional area change. Fused deposition modeling-based 3D printing is a simple and cost-effective fabrication of resilient elastomers using liquid metal. Using a 3D printed microchannel mold, 3D multichannel Galinstan microchannels were fabricated with a serpentine structure for signal stability because it is important to maintain the sensitivity of the sensor even in various mechanical deformations. We performed various electro-mechanical tests for performance characterization and verified the signal stability while stretching and bending. The proposed sensor exhibited good signal stability under 100% longitudinal strain, and the resistance change ranged within 5% of the initial value. We attached the proposed sensor on the finger joint and evaluated the signal change during various finger movements and the application of external forces.

• Physical Therapy Rehabilitation Science
• /
• v.8 no.1
• /
• pp.40-44
• /
• 2019

Objective: The purpose of this study was to examine the changes in postural stability according to ankle fixation in healthy university students. Design: Cross-sectional study. Methods: Thirty healthy subjects (15 males and 15 females, 20.13 years, 167.49 cm, 65.87 kg) were recruited on a voluntary basis. The BT4 system (HUR Laps Oy, Tampere, Finland) was used to measure the static (standing posture with eyes open and eyes closed) and dynamic (external perturbation and limits of stability (LOS) in the forward, backward, left, and right side) balance abilities. External perturbation was measured by the subject's postural sway velocity and area for 20 seconds after being impacted by a gym ball. Static and dynamic stabilities were measured with ankle joint fixation and non-fixation conditions. Ankle fixation was provided using Mueller tape on both ankle joints. Results: For static stability under the standing posture, there was no significant difference between standing with ankle joint fixation and non-fixation conditions. However, dynamic stability (external perturbation and LOS in the forward, backward, left, and right side) was significantly higher in the standing with the non-fixation condition compared to the standing with ankle joint fixation condition (p<0.05). Conclusions: Our results reveal that ankle joint fixation can influence dynamic stability during standing. Thus, we believe that this result provides basic information for making improvements in postural control and may be useful in balance training for fall prevention.

• Korean Journal of Materials Research
• /
• v.29 no.5
• /
• pp.311-316
• /
• 2019

Transparent conducting electrodes are essential components in various optoelectrical devices. Although indium tin oxide thin films have been widely used for transparent conducting electrodes, silver nanowire network is a promising alternative to indium tin oxide thin films owing to its lower processing cost and greater suitability for flexible device application. In order to widen the application of silver nanowire network, the electrical conductance has to be improved while maintaining high optical transparency. In this study, we report the enhancement of the electrical conductance of silver nanowire network transparent electrodes by copper electrodeposition on the silver nanowire networks. The electrodeposited copper lowered the sheet resistance of the silver nanowire networks from $21.9{\Omega}{\square}$ to $12.6{\Omega}{\square}$. We perform detailed X-ray diffraction analysis revealing the effect of the amount of electrodeposited copper-shell on the sheet resistance of the core-shell(silver/copper) nanowire network transparent electrodes. From the relationship between the cross-sectional area of the copper-shell and the sheet resistance of the transparent electrodes, we deduce the electrical resistivity of electrodeposited copper to be approximately 4.5 times that of copper bulk.