• Geomechanics and Engineering
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• v.27 no.6
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• pp.573-582
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• 2021

From the effect of bound water, this study aims to seek the potential reasons for difference of mechanical experiment results of subgrades soils. To attain the comparatively test condition of bound water, dry forming (DF) and wet forming (WF) were used in the specimen forming process before testing, series of laboratory tests, i.e., CBR tests, direct shear tests and compaction tests. The measured optimal moisture contents, maximum dry densities, CBR, cohesion c, and internal friction angle 𝜑 were given contrastive analysis. Then to detect the adsorptive bound water in the subgrade soils, the thermal gravimetric and differential scanning calorimetry (TG-DSC) test were employed under different heating rates. The free water, loosely bound water and tightly bound water in soils were qualitatively and quantitatively analyzed. It was found that due to the different dehydration mechanics, the lost bound water in DF and WF process show their own characteristics. This may lead to the different mechanical properties of tested soils. The clayey particles have a great influence on the bound water adsorbed ability of subgrade soils. The more the clay content, the greater the difference of mechanical properties tested between the two forming methods. Moreover, in highway construction of southern China, the wet forming method is recommended for its higher authenticity in simulating the subgrade filed humidity.

• Clinical and Experimental Reproductive Medicine
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• v.31 no.1
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• pp.9-17
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• 2004

Objective: The aim of this study were to compare the effects of EG and PROH on cryopreservation of mouse and human embryos, and to find the optimal protocol for embryo freezing. Methods: Human embryos derived from fertilized eggs showing 3 pronuclei (PN) and mouse embryos were divided into two groups respectively: dehydrated with 1.5 M EG + 0.2 M sucrose or 1.5 M PROH + 0.2 M sucrose using the slow freezing method. Moreover mouse embryos were controlled the exposure time of cryoprotectant during dehydration or rehydration steps. Results: The survival rates of human embryos were 79.2% (84/106) in EG group and 77.9% (88/113) in PROH group. In mouse embryos, the survival and development rates up to blastocyst were 70.6% (245/347), 44.1% (123/279) in EG group and 62.1% (198/319), 45.1% (123/279) in PROH group, respectively. However, in EG group, partially damaged embryos after thawing were decreased compared to PROH group. In combination group, when the exposure time during dehydration and rehydration were reduced, the survival and embryonic developments were increased slightly, but not significant. Conclusion: Cryopreservation of mouse and human embryos at cleavage stage by using EG or PROH exhibited no statistical difference in the survival rate and/or developmental rate to blastocyst. However, the use of EG for cryopreservation of embryos might reduce the exposure time of the cryoprotectant because of a high permeation of EG and result in lessen its toxic effects.

• The Journal of Internal Korean Medicine
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• v.24 no.2
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• pp.190-202
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• 2003

Object : The effect of Banhabakchulchunma-tang extracts on the hepatic, splenic and cardiac toxicity induced by Doxorubicin administration(Three injection protocol) were monitored using male ICR mice. Methods : The changes of body weight, clinical signs, necropsy findings and organ weights of liver, spleen and heart were observed with blood GOT and GPT levels. Results : 1. Decrease of body weight and The degrees of anorexia, ataxia and dehydration after Doxorubicin treatment were dose-dependently inhibited by Banhabakchulchunma-tang extracts. 2. Increase of absolute and relative liver and heart weight observed in Doxorubicin treatment group were dose-dependently inhibited by Banhabakchulchunma-tang extracts. In addition, the degrees of liver congestion necrotic spot and the degrees of heart congestion enlargement were dose-dependently decreased after Banhabakchulchunma-tang extracts dosing groups compared to that of doxorubicin treatment group. It is also demonstrated that elevated serum GOT and GPT levels in doxorubicin treatment group were significantly decreased in Banhabakchulchunma-tang extracts dosing groups. 3. Decrease of absolute and relative spleen weight observed in doxorubicin treatment group were dose-dependently inhibited by Banhabakchulchunma-tang extracts. In addition, the degrees of splenic atrophy were significantly and dose-dependently decreased after Banhabakchulchunma-tang extracts dosing groups compared to that of doxorubicin treatment group. Conclusion : the toxicity of doxorubicin treatment(decrease of body weights, clinical signs such as anorexia, ataxia and dehydration, changes of organ weights of liver, spleen and heart, elevation of serum GOT and GPT levels) was inhibited and/or prevented by Banhabakchulchunma-tang extracts. According to these results, it is considered that Banhabakchulchunma-tang has some preventive effect against to doxorubicin induced toxicity.

• The Korea Journal of Herbology
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• v.30 no.4
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• pp.65-69
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• 2015

Objectives : The root ofCyanchum wifordii(CW) had been used as herbal medicine, 'Baeksuo', in Korea. However, the root ofCynanchum auriculatum(CA) had also been mis-used as 'Baeksuo' in herbal markets, due to its morphological similarity with CW. This study aimed to compare discriminative features and establish the identification-keys between two herbal medicines using microscopic methods.Methods : Microscopic preparations including fixation, rapid dehydration, paraffin infiltration, paraffin embedding, sectioning, mounting, and staining, were performed and the microscopic features between CW and CA samples were compared.Results : The starch grain of parenchymal cells, the amounts of calcium oxalate crystals, cell sizes, and the shape of phloem were not different between CW and CA samples. However, the clusters of stone cells which were conglomerated at outer cortex were apparently observed in CA sample (4~8 layers of stone cells), but not in CW sample (2~4 layers of stone cells, or not). Xylem of CW consisted of several vessels and fiber bundles which were formed as linear shapes and discontinuous radial lines, while that of CA, in which radial lines was not observed, were shaped as a wedge and scattered near cambium with comparatively few fiber bundles enclosed vessels. Especially, in the xylem of CA, fiber bundles located towards cambium were relatively more developed than those located outward cambium.Conclusions : The identification-keys established in this study would be helpful to discriminate microscopic features between CW and CA.

• Journal of Biosystems Engineering
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• v.41 no.3
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• pp.193-200
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• 2016

Purpose: New low-cost oilseeds are needed to meet an ever-increasing demand for oil for food, pharmaceutical, and industrial applications. African oil bean seed is a tropical crop that is underutilized and has high oil yields, but there have been no studies conducted on its mechanical oil expression up to now. The objective of this work was to investigate the effect of moisture content and seed dimensions on mechanical oil expression from the seeds. Methods: Fresh oil bean seeds were procured, de-hulled, and cleaned. Initial seed moisture content, obtained in accordance with the ASAE standard, was 12% dry basis (db). The seeds were further conditioned by dehydration and rehydration prior to oil expression to obtain four other moisture levels of 8, 10, 14, and 16% db. The major diameter of the seeds was measured using digital vernier calipers, and the seeds were classified into size dimensions (< 40, 41-45, 46-50, 51-55, and > 55 mm). The oil yield and expression efficiency were obtained in accordance with standard evaluation methods. Results: The highest oil yield and expression efficiency (47.74% and 78.96%, respectively) were obtained for a moisture content of 8% db and seed dimensions of < 40 mm, while the lowest oil yield and expression efficiency (41.35% and 68.28%, respectively) were obtained for a moisture content of 14% db and seed dimensions between 51-55 mm. A mathematical model was developed to predict oil yield for known moisture content and seed dimensions, with a coefficient of determination $R^2$ of 95% and the confidence level of the predictive model of 84.17%. The probability of prediction F ratio showed that moisture content influence was more significant than seed dimensions. Conclusions: The higher the moisture content and larger the seed dimensions, the lower the oil yield from African oil bean seeds.

• Journal of the Korean Society of Physical Medicine
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• v.15 no.3
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• pp.61-68
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• 2020

PURPOSE: The purpose of this study was to investigate the current state of rapid weight loss and physical and mental complaints among elite combat athletes who were selected and trained as national representatives. METHODS: A total of 127 combat athletes who had trained at the national training center in 2019 were enrolled. The questionnaire used as the survey tool was interpreted as words that Korean athletes could easily understand based on the Portuguese version of the 'Rapid Weight Loss Questionnaire' (RWLQ). χ² tests was performed to determine the differences in physical and mental changes according to sports and weight loss method. RESULTS: Combat athletes in Korea regularly undergo rapidly weight loss within a short period of time prior to competition. There were statistically similar results in terms of weight loss method, physical and mental changes and information about weight loss according to the sport. Weight loss methods often limit food and water intake and dehydrate. The physical complaints associated with them are symptoms such as "no energy", "dizziness", and "muscle spasms". The mental complaints include "irritability", "concentration loss" and "anxiety". These symptoms can be caused by side effects such as food intake limitation, water restriction and dehydration. Information sources for weight loss were in the order of "senior or colleagues", "supervisor or coach", and "Internet". No information was obtained from a doctor or dietitian. CONCLUSION: These results provide a baseline for predicting proper weight loss in athletes and provide useful information for developing performance enhancement as well as weight loss.

• Clinical and Experimental Pediatrics
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• v.48 no.10
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• pp.1116-1120
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• 2005

Purpose : Although the rotavirus-related neonatal death occurred in western part of Kyeonggi Province recently, there were just a few reports about rotavirus gastroentertis in domestic since 2000. We proposed to investigate changes of epidemiology and clinical features of rotavirus gastroenteritis for the last 2 years. Methods : We selected 166 patients diagnosed as gastroenteritis from January, 2002 to July, 2003 and reviewed the admission records retrospectively such as age distribution, sex ratio, seasonal distribution, admission period, laboratory data and dehydration type in the rotavirus group(RVG) and non-RVG. Results : The percentage of patient under 3 years was 77% on RVG. The non-RVG showed even age distribution(P<0.05). In RVG, patients occurred in March frequently and 52% occurred from January to March. In non-RVG, patients occurred highly in February and July(P<0.05). The average of admission period was higher in RVG than non-RVG(P<0.05). The percentage of patient admitted for over 10 days was 8% in the RVG. In dehydration severity, the RVG showed mild(51%), moderate(44%) and severe(5%) respectively, but non-RVG showed only mild dehydration(P<0.05). The laboratory findings' did not have statistic significance between RVG and non-RVG. Conclusion : Compared to the previous studies, seasonal peak prevalence of rotavirus gastroenteritis changed from autumn to spring and patients over 3 years increased. Therefore, we suggest that there are variable serotypes of rotavirus domestically and there is a need for reinvestigation about clinical features and serotypes of rotavirus gastroenteritis.

• Korean Journal of Weed Science
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• v.8 no.3
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• pp.309-316
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• 1988

Several experiments were conducted to investigate the achene viability and growth characteristics of Eclipta prostrata (L.) L. No dormancy and no after-ripening requirement were found for E. prostrata achenes. When achenes were stored at room temperature, germination did not decrease with up to 5 months storage. Large differences in loss of viability of E. prostrata achenes occurred when different dehydration methods were used. Immediate dehydration resulted in high viability, but slow dehydration resulted in severe loss of viability. Achene viability at shallow burial depths (5 and 10 cm deep) was lower under upland soil conditions than under lowland soil conditions. Seedling growth was greatly reduced when flooding to a depth of 10 cm occurred at or before the 4-leaf stage. Flooding after the 4-leaf stage stimulated stem elongation. Branching started from the second week and usually terminated at the tenth week. Leaf size was determined by the branch which are related to the assimilate supply. Flowering of E. prostrata started during the fifth week after emergence, and mature achenes were produced from the sixth week. Ten to 14 days were needed for the achenes to mature. About 14,000 achenes were produced on each plant. Achene production per week increased from the sixth week to the tenth week and thereafter it declined. The average number of achenes per inflorescence decreased with delay in flowering.

• Korean Chemical Engineering Research
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• v.45 no.6
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• pp.566-572
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• 2007

Two hybrid catalysts for the direct synthesis of DME were prepared and the catalytic activity of these catalysts were investigated. The hybrid catalyst for the direct synthesis of DME was composed as the catalytic active components of methanol synthesis and dehydration. The methanol synthesis catalyst was formed from the precursor contained Cu and Zn, the methanol dehydration catalyst was used ${\gamma}-Al_2O_3$. As PM-CZ+D and CP-CZA/D, Two hybrid catalysts were prepared by physical mixing method (PM-CZ+D) and precipitation method (CP-CZA/D), respectively. PM-CZ+D was prepared by physically mixing methanol synthesis catalyst and methanol dehydration catalyst, CP-CZA/D was prepared by depositing Cu-Zn or Cu-Zn-Al components on ${\gamma}-Al_2O_3$. The crystallinity and the surface morphology of synthesized catalyst were analyzed by X-ray diffraction (XRD) and scanning electron microscope (SEM) to investigate the physical property of prepared catalyst. And BET surface area by $N_2$ adsorption and the surface area of Cu by $N_2O$ chemisorption were investigated about the hybrid catalysts. In addition, catalytic activity of these hybrid catalysts was examined with varying reaction conditions. At that time, the reaction temperature of $250{\sim}290^{\circ}C$, the reaction pressure of 50~70 atm, the $[H_2]/[CO]$ mole ratio of 0.5~2.0 and the space velocity of $1,500{\sim}6,000h^{-1}$ were investigated the catalytic activity. From these results, it was confirmed that the reactivity of CP-CZA/D was higher than that of PM-CZ+D. When the conditions of reaction temperature, pressure, $[H_2]/[CO]$ ratio and space velocity were $260^{\circ}C$, 50 atm and 1.0, $3,000h^{-1}$ respectively, CO conversion using CP-CZA/D hybrid catalyst was 72% and the CO conversion of CP-CZA/D was more than 20% compared with the CO conversion of PM-CZ+D. It was known that Cu surface area of CP-CZA/D hybrid catalyst was higher than that of hybrid PM-CZ+D catalyst using $N_2O$ chemisorption. It was assumed that the catalytic activity was improved because Cu particle of hybrid catalyst prepared by precipitation method was well dispersed.

• Journal of Ginseng Research
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• v.44 no.3
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• pp.490-495
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• 2020

Background: Ginsenoside Rk1, a saponin component isolated from heat-processed Panax ginseng Meyer, has been implicated in the regulation of antitumor and anti-inflammatory activities. Although our previous studies have demonstrated that ginsenoside Rg3 significantly attenuated the activation of NMDA receptors (NMDARs) in hippocampal neurons, the effects of ginsenosides Rg5 and Rk1, which are derived from heat-mediated dehydration of ginsenoside Rg3, on neuronal NMDARs have not yet been elucidated. Methods: We examined the regulation of NMDARs by ginsenosides Rg5 and Rk1 in cultured rat hippocampal neurons using fura-2-based calcium imaging and whole-cell patch-clamp recordings. Results: The results from our investigation showed that ginsenosides Rg3 and Rg5 inhibited NMDARs with similar potencies. However, ginsenoside Rk1 inhibited NMDARs most effectively among the five compounds (Rg3, Rg5, Rk1, Rg5/Rk1 mixture, and protopanaxadiol) tested in cultured hippocampal neurons. Its inhibition is independent of the NMDA- and glycine-binding sites, and its action seems to involve in an interaction with the polyamine-binding site of the NMDAR channel complex. Conclusion: Taken together, our results suggest that ginsenoside Rk1 might be a novel component contributable to the development of ginseng-based therapeutic treatments for neurodegenerative diseases.