• Journal of Astronomy and Space Sciences
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• v.36 no.2
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• pp.61-68
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• 2019

We have investigated the variations of sporadic E (Es) layer using the measurements of digisondes at Icheon ($37.14^{\circ}N$, $127.54^{\circ}E$, IC) and Jeju ($33.4^{\circ}N$, $126.30^{\circ}E$, JJ) in 2011-2018. The Es occurrence rate and its critical frequency (foEs) have peak values in summer at both IC and JJ in consistent with their known seasonal variations at mid-latitudes. The virtual height of the Es layer (h'Es) during equinox months is greater than that in other months. It may be related to the similar variation of meteor peak heights. The h'Es shows the semidiurnal variations with two peaks at early in the morning and late in the afternoon during equinoxes and summer. However, the semi-diurnal variation is not obvious in winter. The semi-diurnal variation is generally thought to be caused by the semi-diurnal tidal variation in the neutral wind shear, whose measurements, however, are rare and not available in the region of interest. To investigate the formation mechanism of Es, we have derived the vertical ion drift velocity using the Horizontal Wind Model (HWM) 14, International Geomagnetic Reference Field, and Naval Research Laboratory Mass Spectrometer and Incoherent Scatter Radar-00 models. Our results show that h'Es preferentially occur at the altitudes where the direction of the vertical ion velocity changes. This result indicates the significant role of ion convergence in the creation of Es.

• Journal of Korean Society of Health-System Pharmacists
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• v.35 no.4
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• pp.430-440
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• 2018

Background : Hyponatremia is the most common electrolyte disturbance in hospitalized patients and has been associated with increased morbidity and mortality. Tolvaptan, a vasopressin receptor antagonist, is increasingly used for the treatment of euvolemic and hypervolemic hyponatremia. The aim of this study was to evaluate the effectiveness and safety of tolvaptan for the management of hyponatremia. Methods : This study was a retrospective evaluation of 106 patients who received at least one dose of tolvaptan for hyponatremia at a single tertiary academic hospital between January 2014 and June 2015. The primary endpoint was the change in serum sodium concentration after tolvaptan administration within 24 hours, with secondary endpoints of overcorrection and adverse effects. Results : The mean initial dose of tolvaptan was $20.2{\pm}7.2mg$ and the median duration of treatment was 15 days (range, 1-261 days). The maximal changes in sodium levels at 24 and 48 hours were $8.2{\pm}4.7mmol/L$ and $10.5{\pm}15.3mmol/L$, respectively. Of 99 patients in whom sodium concentrations were followed up, sodium overcorrection was observed in 26 (26.3%) patients, which was associated with concomitant use of an enzyme inhibitor (odds ratio [OR] = 4.80, 95% Cl: 1.27-18.15). However, sex, body mass index (BMI), serum albumin, a daily dose of tolvaptan, and concomitant use of hypertonic saline did not show any significant difference in overcorrection. The most commonly reported adverse effects were mild and related to aquaresis, such as polyuria, thirst, and constipation. However, severe adverse effects such as hyperkalemia, hypotension, and one death related to osmotic demyelination were also reported. Conclusions : Tolvaptan is effective for treating hyponatremia. Nevertheless, the drug should be used cautiously due to serious adverse effects related to sodium overcorrection.

• The Journal of Korean Obstetrics and Gynecology
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• v.34 no.2
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• pp.142-156
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• 2021

Objectives: The purpose of this study is to report the results of Korean medicine treatment infertility support program in Chungcheongnam-do in 2019. Methods: Participants of Korean medicine treatment infertility support program were provided with Korean herbal medicine, acupuncture and moxibustion for 3 months and followed up for 3 months after the treatments. A total of 115 women out of 125 applicants completed the treatment, and 106 participants' data was collected. The data containing pregnancy rates, characteristics of subjects, treatments, and satisfaction of the program were analyzed. Results: After the treatment, 18 out of 115 subjects became pregnant and had a pregnancy rate of 15.7%. There were no significant differences in factors such as age, body mass index (BMI), social history, infertility period, and history of infertility treatment between pregnant and non-pregnant groups except smoking. Some of the subjects reported positive changes in the menstrual conditions such as cycle, volume and menstrual pain. More than 80% of the subjects answered that they were satisfied with the program in the survey questionnaire. Conclusions: Based on this report, the clinical data were obtained from the infertility treatment program. This study can be used as basic data to help establish infertility support programs and subsequent policies.

• Journal of Microbiology and Biotechnology
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• v.31 no.10
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• pp.1430-1437
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• 2021

Cronobacter sakazakii is an opportunistic pathogenic bacterium found in powdered infant formula and is fatal to neonates. Antibiotic resistance has emerged owing to overuse of antibiotics. Therefore, demand for high-yield bacteriophages as an alternative to antibiotics has increased. Accordingly, we developed a modified mass-production method for bacteriophages by introducing a two-stage self-cycling (TSSC) process, which yielded high-concentration bacteriophage solutions by replenishing the nutritional medium at the beginning of each process, without additional challenge. pH of the culture medium was monitored in real-time during C. sakazakii growth and bacteriophage CS01 propagation, and the changes in various parameters were assessed. The pH of the culture medium dropped to 5.8 when the host bacteria reached the early log phase (OD₅₄₀ = 0.3). After challenge, it decreased to 4.65 and then recovered to 4.94; therefore, we set the optimum pH to challenge the phage at 5.8 and that to harvest the phage at 4.94. We then compared phage production during the TSSC process in jar-type bioreactors and the batch culture process in shaker flasks. In the same volume of LB medium, the concentration of the phage titer solution obtained with the TSSC process was 24 times higher than that obtained with the batch culture process. Moreover, we stably obtained high concentrations of bacteriophage solutions for three cycles with the TSSC process. Overall, this modified TSSC process could simplify large-scale production of bacteriophage CS01 and reduce the unit cost of phage titer solution. These results could contribute to curing infants infected with antibiotic-resistant C. sakazakii.

• Earthquakes and Structures
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• v.20 no.1
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• pp.55-70
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• 2021

In urban cities, buildings were built in the neighborhood, these buildings influence each other through structure-soilstructure interaction (SSSI) and seismic pounding due to limited separation distance in-between. Generally, the effects of the interaction between soil and structure are disregarded during seismic design and analysis of superstructure. However, the system of soil-base adversely changes structural behavior and response demands. Thus, the vibration characteristics plus the seismic response of a building are not able to be independent of those in adjacent buildings. The interaction between structure, soil, and structure investigates the action of the attendance of adjacent buildings to the others by the interaction effect of the sub-soil under dynamic disturbances. The main purpose of this research is to analyze the effects of SSSI and seismic pounding on the behavior of adjacent buildings. The response of a single structure or two adjacent structures with shallow raft base lying on soft soil are studied. Three dimensions finite element models are developed to investigate the effects of pounding; gap distance; conditions of soil; stories number; a mass of adjacent building and ground excitation frequency on the seismic responses and vibration characteristics of the structures. The variation in the story displacement, story shear, and story moment responses demands are studied to evaluate the presence effect of the adjacent buildings. Numerical results acquired using conditions of soil models are compared with the condition of fixed support and adjacent building models to a single building model. The peak responses of story displacement, story moment, and story shear are studied.

• Journal of the Regional Association of Architectural Institute of Korea
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• v.21 no.4
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• pp.15-26
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• 2019

In recent years, researchers are increasingly trying to use BIM-based 3D models for BIM nD design such as 4D (3D + Time) and 5D (4D + Cost). However, there are still many problems in efficiently using process management based on the BIM information created at each design stage. Therefore, this study proposes a method to automate 4D and 5D design support in each design stage by using BIM-based Dynamo algorithm. To do this, I implemented an algorithm that can automatically input the process information needed for 4D and 5D by using Revit's Add-in program, Dynamo. In order to support the 4D design, the algorithm was created to enable automatic process simulation by synchronizing process simulation information (Excel file) through the Navisworks program, BIM software. The algorithm was created to automatically enable process simulation. And to support the 5D design, the algorithm was developed to enable automatic extraction of the information needed for mass production from the BIM model by utilizing the dynamo algorithm. Therefore, in order to verify the 4D and 5D design support algorithms, we verified the applicability through consultation with related workers and experts. As a result, it has been demonstrated that it is possible to manage information about process information and to quickly extract information from design and design changes. In addition, BIM data can be used to manage and input the necessary process information in 4D and 5D, which is advantageous for shortening construction time and cost. This study will make it easy to improve design quality and manage design information, and will be the foundation for future building automation research.

• The Journal of Internal Korean Medicine
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• v.43 no.2
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• pp.184-190
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• 2022

Objectives: This study aims to report the clinical efficacy of Korean medical treatment of a patient with nonalcoholic fatty liver disease accompanied by obesity and dyslipidemia. Methods: A 52-year-old man with nonalcoholic fatty liver disease, obesity, and dyslipidemia was treated with Saenggangunbi-tang extract from November 3, 2021 to January 8, 2022. During the treatment period, the patient also undertook exercise and maintained a hypocaloric diet to reduce body weight. Changes were observed in the patient's symptoms, laboratory findings, such as liver enzymes and lipid profiles, and bioelectrical impedance analyzer results. Results: After taking Saenggangunbi-tang extract for approximately two months, with concomitant adjustments to exercise and diet, the serum levels of liver enzymes and triglyceride were decreased and the patient's body weight, body mass index, hepatic steatosis index, and visceral fat area were also reduced. In addition, symptoms including fatigue and dyspepsia improved. Conclusion: This study suggests that Saenggangunbi-tang extract with exercise and a regulated diet could be a helpful treatment strategy for managing nonalcoholic fatty liver disease with metabolic disorders.

• Geomechanics and Engineering
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• v.30 no.4
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• pp.345-352
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• 2022

When rock burst occurs, the damaged coal, rock and other fragments can be ejected to the roadway at a speed of up to 10 m/s. It is extremely harmful to personnel and mining equipment, and seriously affects the mining activities. In order to study the energy evolution characteristics, especially kinetic energy, in the process of rock mass failure, this paper first analyzes the energy changes of the rock in different stages under uniaxial compression. The formula of the kinetic energy of rock sample considering the energy from the indenter of the testing machine is obtained. Then, the uniaxial compression tests with different stiffness ratios of the indenter and rock sample are simulated by numerical simulation. The kinetic energy U_d, elastic strain energy U_e, friction energy U_f, total input energy U and surface energy U_θ of crack cracking are analyzed. The results show that: The stiffness ratio has influence on the peak strength, peak strain, U_d, U_e, U_θ, U_f and U of rock samples. The variation trends of strength, strain and energy with stiffness are different. And when the stiffness ratio increases to a certain value, if the stiffness of the indenter continues to increase, it will have no longer effect on the rock sample.

• Journal of Mushroom
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• v.20 no.4
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• pp.187-192
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• 2022

Wolfiporia cocos is an edible fungus commercially cultivated in Asia. To investigate metabolic changes of W. cocos mycelia under both light and dark culture conditions, gas chromatography mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC) analyses were performed. In terms of the total amount of sugars, alcohols, amino acids, organic acids, fatty acids, and purines, there no significant differences between the W. cocos mycelia cultivated under light (L) or dark (D) conditions (p < 0.05). However, there were some differences with respect to the production of particular sugars and proteins. The levels of trehalose (L: 17.2 ± 0.3% vs. D: 13.9 ± 1.6%), maltose (L: 0.9 ± 0.1% vs. D: 0.3 ± 0.1%), turanose (L: 0.7 ± 0.2% vs. D: 0.1 ± 0.1%), glutamine (L: 1.6 ± 0.3% vs. D: 0.7 ± 0.2%), and proline (L: 0.3 ± 0% vs. D: 0.1 ± 0%) were all significantly higher under light condition (p < 0.05). In contrast, the levels of galactose (L: 13.7 ± 1.2% vs. D: 17.6 ± 2.0%), aspartic acid (L: 0.6 ± 0.1 % vs. D: 0.9 ± 0.1%), cystathionine (L: 0.6 ± 0.1% vs. D: 0.8 ± 0 %), and malic acid (L: 0.7 ± 0.1% vs. D: 1.2 ± 0.1%) were higher under the dark condition. It is worth noting that the amount of pachymic acid, a pharmaceutically active compound of W. cocos, was 1.68 times greater under the light condition (p < 0.05).

• Structural Engineering and Mechanics
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• v.85 no.2
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• pp.197-206
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• 2023

The deterioration caused by chloride penetration and carbonation plays a significant role in a concrete structure in a marine environment. The chloride corrosion in some marine concrete structures is invisible but can be dangerous in a sudden collapse. Therefore, as a novelty, this research investigates the ability of a non-destructive damage detection method named the Power Spectral Density (PSD) to diagnose damages caused only by chloride ions in concrete structures. Furthermore, the accuracy of this method in estimating the amount of annual damage caused by chloride in various parts and positions exposed to seawater was investigated. For this purpose, the RC Arosa bridge in Spain, which connects the island to the mainland via seawater, was numerically modeled and analyzed. As the first step, each element's bridge position was calculated, along with the chloride corrosion percentage in the reinforcements. The next step predicted the existence, location, and timing of damage to the entire concrete part of the bridge based on the amount of rebar corrosion each year. The PSD method was used to monitor the annual loss of reinforcement cross-section area, changes in dynamic characteristics such as stiffness and mass, and each year of the bridge structure's life using sensitivity equations and the linear least squares algorithm. This study showed that using different approaches to the PSD method based on rebar chloride corrosion and assuming 10% errors in software analysis can help predict the location and almost exact amount of damage zones over time.