• Magazine of the Korean Society of Agricultural Engineers
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• v.34 no.1
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• pp.41-48
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• 1992

Various soil behaviors usually occurring in the geotechnical problems, such as, cutting and embankments, stability of slope, seepage, consolidations, shearing failures and liquefaction, should be predicted and analyzed in any way. An approach of these predictions may be followed by the development of the constitutive equations as first and subsequently solved by numerical methods. The purpose of this paper is develop the constitutive equation of sands uder monotonic or cyclic loadings. The constitutive equation which is based on elasto-plastic theory, modified anisotropic consolidated stress parameter by Sekiguchi et al and Pender's theory is derived. And the equation is included a new stress parameter, hardening function, Bauschinger's effects and Pender's theory. The model is later evaluated and confirmed the validity by the test data of Ottawa sand, Banwol sand Hongseong sand. The following conclustions may be drawn: 1. The consititutive equation which is based on elasto-plastic theory, modified anisotropic consolidated stress parpameter by Sekiguchi et al and Pender's theory is derived. The equation in included a new stress parameter, hardening function, Bauschinger's effect and Pender's theory. 2. For Ottawa sand, the result of the constitutive equation shows a better agreement than that of Oka et al. The result of axial strain agrees well with the tested data. However, the result of horizontal strain is little bit off for the cyclic loadings or large stress. It is thought that the deviation may be improved by considering Poisson's ratio and precise measurement of shear modulus. 3. Banwol sand is used for the strain and stress tests with different relative densitites and confining pressures. The predeicted result shows a good agreement with the tested data because the required material parameters were directly measurd and determined form this laboratory. 4. For Hongseong sand, the tests under same amplitude of cyclic deviatoric stress shows a similar result with the tested data in absolute strain. It shows the acute shape of turning point because the sine wave of input is used in the test but the serrated wave in prediction.

• Safety and Health at Work
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• v.8 no.1
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• pp.94-98
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• 2017

Background: Physical activity (PA) is ranked as a leading health indicator and the workplace is a key setting to promote PA. The purpose of this study was to examine how goal-setting and exercise self-efficacy (SE) during a health promotion program influenced PA level among Japanese workers. Methods: Using a cross-sectional study design, we surveyed 281 employees. The short version of the International Physical Activity Questionnaire was used to assess PA level. Exercise SE was assessed using a partially modified version of Oka's exercise SE scale. Personal goals were assessed as the total numbers of "yes" responses to five items regarding "details of personal goals to perform PA". A mediational model was used to examine whether exercise SE mediates between the number of personal goals and PA level. Results: The mean age of the participants was 46.3 years, 76.2% were men, and the most common occupational category was software engineer (30.6%). The average PA level per week exceeded the recommended level in 127 participants (45.2%). One hundred and eighty-four participants (65.5%) set some form of concrete personal goal to perform PA. The relationship between the number of personal goals and PA level was mediated by exercise SE. Conclusion: Our study showed that exercise SE mediates goal-setting and increases PA. The results suggest that the components of PA promotion programs should be tailored to enhance participants' confidence in performing PA.

• Journal of Ginseng Research
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• v.47 no.1
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• pp.144-154
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• 2023

Background: As the major pathophysiological feature of obstructive sleep apnea (OSA), chronic intermittent hypoxia (CIH) is vital for the occurrence of cardiovascular complications. The activation of calpain-1 mediates the production of endothelial reactive oxygen species (ROS) and impairs nitric oxide (NO) bioavailability, resulting in vascular endothelial dysfunction (VED). Ginsenoside Rg1 is thought to against endothelial cell dysfunction, but the potential mechanism of CIH-induced VED remains unclear. Methods: C57BL/6 mice and human coronary artery endothelial cells (HCAECs) were exposed to CIH following knockout or overexpression of calpain-1. The effect of ginsenoside Rg1 on VED, oxidative stress, mitochondrial dysfunction, and the expression levels of calpain-1, PP2A and p-eNOS were detected both in vivo and in vitro. Results: CIH promoted VED, oxidative stress and mitochondrial dysfunction accompanied by enhanced levels of calpain-1 and PP2A and reduced levels of p-eNOS in mice and cellular levels. Ginsenoside Rg1, calpain-1 knockout, OKA, NAC and TEMPOL treatment protected against CIH-induced VED, oxidative stress and mitochondrial dysfunction, which is likely concomitant with the downregulated protein expression of calpain-1 and PP2A and the upregulation of p-eNOS in mice and cellular levels. Calpain-1 overexpression increased the expression of PP2A, reduced the level of p-eNOS, and accelerated the occurrence and development of VED, oxidative stress and mitochondrial dysfunction in HCAECs exposed to CIH. Moreover, scavengers of O₂^·-, H₂O₂, complex I or mitoKATP abolished CIH-induced impairment in endothelial-dependent relaxation. Conclusion: Ginsenoside Rg1 may alleviate CIH-induced vascular endothelial dysfunction by suppressing the formation of mitochondrial reactive oxygen species through the calpain-1 pathway.

• Journal of the Korean Geotechnical Society
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• v.24 no.1
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• pp.25-35
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• 2008

It has been recognized that the behaviour of unsaturated soil plays an important role in geomechanics. However, up to now, only a few experimental data are available for the technical difficulties related to both volume changes and suction measurements. In this study, the volume changes of unsaturated compacted silty soil were monitored with proximeter during various triaxial compression tests, which gave a realistic estimation in the volume changes of unsaturated soil sample. From the test results, the behaviours of wetting-induced collapses are observed during the drainage/water absorption tests. Under exhausted-drained conditions during shearing, the shear strength increases with an increasing initial suction. On the other hand, the volume changes become small with an increase in the initial suction. And, the volumetric strain during shearing is independent of the confining pressure.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.26 no.4
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• pp.181-192
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• 2023

Purpose: The development of assistive devices has allowed for the performance of capsule endoscopy in children. Anticipating the capsule's transit time could affect the efficacy of the investigation and potentially minimize the fasting period. This study determined the predictors of small bowel transit time for small-bowel capsule endoscopy in children and adolescents with inflammatory bowel disease. Methods: We retrospectively examined children and adolescents with inflammatory bowel disease who underwent capsule endoscopy by the age 18 at a Japanese tertiary care children's hospital. Small bowel transit time predictors were analyzed using multiple regression with explanatory variables. Results: Overall, 92 patients, aged 1-17 years, with inflammatory bowel disease (63 Crohn's disease and 29 ulcerative colitis cases) were examined for factors affecting small bowel transit time. In the simple regression analysis, diagnosis, age, height, weight, serum albumin, general anesthesia, and small intestine lesions were significantly associated with small bowel transit time. In the multiple regression analyses, serum albumin (partial regression coefficient: -58.9, p=0.008), general anesthesia (partial regression coefficient: 127, p<0.001), and small intestine lesions (partial regression coefficient: 30.1, p=0.037) showed significant associations with small bowel transit time. Conclusion: Hypoalbuminemia, the use of general anesthesia for endoscopic delivery of the capsule, and small intestine lesions appeared to be predictors of prolonged small bowel transit time in children and adolescents with inflammatory bowel disease. Expecting the finishing time may improve examination with a fasting period reduction, which benefits both patients and caregivers.

• Journal of Gastric Cancer
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• v.23 no.4
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• pp.512-522
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• 2023

Purpose: Dental floss clip (DFC) traction-assisted endoscopic submucosal dissection (ESD) is widely performed owing to its simplicity. This study aimed to clarify the appropriate indications for the DFC traction method in early gastric cancer when ESD is performed by less-experienced endoscopists. Methods and Methods: We retrospectively analyzed 1,014 consecutive patients who had undergone gastric ESD performed by less-experienced endoscopists between January 2015 and December 2020. Gastric ESD was performed without DFC in all cases before December 2017 [DFC (-) group, 376 cases], and ESD was performed with DFC in all cases after January 2018 [DFC (+) group, 436 cases]. The procedure time and rates of en bloc resection, complete resection, and adverse events of the groups were compared. Results: The procedure time did not differ significantly between the 2 groups. However, when comparing lesions >20 mm, the procedure time in the DFC (+) group was significantly shorter than that in the DFC (-) group (95±46 vs. 75±31, P<0.01). The procedure time for lesions located in the greater curvature of the upper or middle stomach and lesions >20 mm located in the lesser curvature side of the stomach in the DFC (+) group was significantly shorter than that in the DFC (-) group. Conclusions: The indications for DFC during gastric ESD by less-experienced endoscopists include lesions located in the greater curvature of the upper or middle stomach, and lesions >20 mm located in the lesser curvature of the stomach.

• Korean Circulation Journal
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• v.53 no.2
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• pp.69-91
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• 2023

Cardio-oncology is an emerging multi-disciplinary field, which aims to reduce morbidity and mortality of cancer patients by preventing and managing cancer treatment-related cardiovascular toxicities. With the exponential growth in cancer and cardiovascular diseases in Asia, there is an emerging need for cardio-oncology awareness among physicians and country-specific cardio-oncology initiatives. In this state-of-the-art review, we sought to describe the burden of cancer and cardiovascular disease in Asia, a region with rich cultural and socio-economic diversity. From describing the uniqueness and challenges (such as socio-economic disparity, ethnical and racial diversity, and limited training opportunities) in establishing cardio-oncology in Asia, and outlining ways to overcome any barriers, this article aims to help advance the field of cardio-oncology in Asia.

• Clinical and Experimental Pediatrics
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• v.51 no.4
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• pp.377-382
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• 2008

Purpose : The aim of this study is to assess the usefulness of skin test by an inactivated, 1/50 diluted solution of attenuated varicella vaccine in evaluating the immune status to varicella. Methods : Total 41 subjects (22 males, 19 females, aged 1-32 years) were enrolled from July to August, 2005. Past medical history including varicella infection, varicella vaccination were investigated through questionnaires. The skin test solution was prepared from solution of attenuated varicella vaccine(Oka strain) which was inactivated by exposure to room temperature for 10 days and diluted at 1/50 with normal saline. Skin test was done by injecting 0.1 mL of the solution intradermally into the volar surface of the right forearm and sterile normal saline was used as a control on the left forearm. Positive reaction was defined when the transverse diameter of the induration was 5 mm or more. Serum varicella zoster virus specific IgG antibody test by ELISA (enzyme-linked immunosorbent assay) was done. Results : In adults, the sensitivity of the varicella zoster virus skin test compared to ELISA was 94.7% and the positive predictive value was 100%. In children, both the positive predictive value and specificity were 100% but the sensitivity and the negative predictive value were 50% and 30.7% respectively. Children showed smaller skin test reactivity compared to adults. Conclusion : The varicella zoster virus skin test using inactivated, 1/50 diluted solution of attenuated varicella vaccine was proved as one of the useful tools for evaluating the immunity and susceptibility of the varicella zoster virus.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.1
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• pp.39-43
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• 2003

Dietary fatty acid including mainly palmitic acid and stearic acid was fed to fattening cattle and its effect on body weight gain, plasma lipid contents and rumen liquid fermentation in vitro was examined. In expt. 1, the effect of dietary fatty acid on body weight gain and plasma lipid concentrations was examined. In the control diet group, cattle were fed 1 kg/day of rice straw and concentrate which satisfied the requirement. In the fatty acid group, cattle were given 250 g/d of fatty acid with the same diet of the control diet group. In the excess concentrate group, cattle were given the same diet of the control diet group plus 735 g/d of concentrate corresponding to the same TDN of 250 g/d of fatty acid. Diets were given for 7 days. Body weight gain of cattle given dietary fatty acid was significantly greater than that of cattle fed only rice straw and concentrate. When dietary fatty acid was added to cattle feed, plasma NEFA and HDL-cholesterol concentrations increased. In expt. 2, the influence of dietary fatty acid on gas production and VFA profile in the rumen liquid was investigated in vitro. In the control group, 10 mg of rice straw and 90 mg of concentrate were incubated in the rumen fluid. In the excess concentrate group, 10 mg of rice straw and 97.5 mg of concentrate were incubated. In the fatty acid group, 10 mg of rice straw, 90 mg of concentrate and 2.5 mg of fatty acids were incubated. The rumen liquid mixed with feed materials was incubated for 24 h and the cumulative gas volume was measured. The VFA profile was also measured. Cumulative gas volume in the rumen liquid with fatty acid was equal to the control. Excess concentrate increased cumulative gas volume compared to the fatty acid group. There was no significant difference in total VFA concentration between experimental diet groups. It is suggested that dietary fatty acid has the potency to improve growth performance in fattening cattle without failure in rumen fermentation.

• Journal of the Korean Geotechnical Society
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• v.30 no.6
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• pp.5-21
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• 2014

It has been pointed out that the collapses of unsaturated road embankments caused by earthquake are attributed to high water content caused by the seepage of the underground water and/or the rainfall infiltration. Hence, it is important to study influences of water content on the dynamic stability and deformation mode of unsaturated road embankments for development of a proper design scheme including an effective reinforcement to prevent severe damage. This study demonstrates dynamic centrifugal model tests with different water contents to investigate the effect of water content on deformation and failure behaviors of unsaturated road embankments. Based on the measurement of displacement, the pore water pressure and the acceleration during dynamic loading, dynamic behavior of the unsaturated road embankments with about optimum water content and the higher water content than the optimum one have been examined. In addition, an image analysis has revealed the displacement field and the distributions of strains in the road embankment, by which deformation mode of the road embankment with higher water content has been clarified. It has been confirmed that in the case of higher water content the settlement of the crown is large mainly owing to the volume compression underneath the crown, while the small confining pressure at the toe and near the slope surface induces large shear deformation with volume expansion.