• Geomechanics and Engineering
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• v.33 no.1
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• pp.11-18
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• 2023

This study explores a new energy partitioning approach to determine the fracture toughness of 3-D printed pristine/recycled high density polyethylene (HDPE) blends employing the essential work of fracture (EWF) concept. The traditional EWF approach conducts a uniaxial tensile test with double-edge notched tensile (DENT) specimens and measures the total energy defined by the area under a load-displacement curve until failure. The approach assumes that the entire total energy contributes to the fracture process only. This assumption is generally true for extruded polymers that fracture occurs in a material body. In contrast to the traditional extrusion manufacturing process, the current 3-D printing technique employs fused deposition modeling (FDM) that produces layer-by-layer structured specimens. This type of specimen tends to include separation energy even after the complete failure of specimens when the fracture test is conducted. The separation is not relevant to the fracture process, and the raw experimental data are likely to possess random variation or noise during fracture testing. Therefore, the current EWF approach may not be suitable for the fracture characterization of 3-D printed specimens. This paper proposed a new energy partitioning approach to exclude the irrelevant energy of the specimens caused by their intrinsic structural issues. The approach determined the energy partitioning location based on experimental data and observations. Results prove that the new approach provided more consistent results with a higher coefficient of correlation.

• Nutrition Research and Practice
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• v.17 no.4
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• pp.631-640
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• 2023

BACKGROUND/OBJECTIVES: Coffee is a complex chemical mixture, with caffeine being the most well-known bioactive substance. The immunomodulatory and anti-inflammatory properties of coffee and caffeine impact health in various aspects, including the respiratory system. The objective is to investigate the effects of coffee and caffeine on airway hyperresponsiveness and allergic reactions, as well as to analyze and compare associated cytokine profiles. MATERIALS/METHODS: BALB/c mice were intraperitoneally sensitized with ovalbumin (OVA) and given OVA inhalation to induce airway hypersensitivity. Two weeks after sensitization, they were intragastrically gavaged with coffee or caffeine, both containing 0.3125 mg caffeine, daily for 4 weeks. Control mice were fed with double-distilled water. Serum OVA-specific antibody levels were measured beforehand and 5 weeks after the first gavage. Airway hyperresponsiveness was detected by whole body plethysmography after gavage. Cytokine levels of bronchoalveolar lavage and cultured splenocytes were analyzed. RESULTS: Coffee effectively suppressed T helper 2-mediated specific antibody response. Airway responsiveness was reduced in mice treated with either coffee or caffeine. Compared to the control, coffee significantly reduced OVA-specific immunoglobulin (Ig) G, IgG1 and IgE antibody responses (P < 0.05). Caffeine also attenuated specific IgG and IgG1 levels, though IgE level was unaffected. Coffee significantly reduced interleukin (IL)-4 and increased IL-10 concentration in spleen cells and bronchoalveolar lavage fluid (P < 0.05). CONCLUSIONS: Coffee effectively attenuated airway hyperresponsiveness and systemic allergic responses induced by OVA food allergen in mice. As a complex composition of bioactive substances, coffee displayed enhanced immunomodulatory and anti-inflammatory effects than caffeine.

• Journal of Korean Foot and Ankle Society
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• v.27 no.1
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• pp.12-16
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• 2023

Purpose: Postoperative exercise for acute Achilles tendon rupture is important for a patient's return to daily life and sports. On the other hand, the protocol requires considerable effort to educate patients and continuous checking. This study evaluated the outcome of a new simple and delayed rehabilitation protocol after Achilles tendon rupture repair. Materials and Methods: From July 2014 to November 2020, one hundred eighty-three patients were operated on by one surgeon. The exercise protocol was classified into two methods. One group (immediate protocol, control group) started immediate full weight bearing with a 20° plantar flexion range of motion from two days postoperatively. Ankle dorsiflexion was restricted to 0°. The other group (delayed protocol, case group) started full weight bearing with a controlled ankle motion boot from two weeks postoperatively. No range of motion exercise was allowed until six weeks postoperatively. Age, sex, body mass index, ankle range of motion, muscle power, time to return to previous physical activity, functional score, and complication rate were evaluated. The results of the two groups were compared using a Mann-Whitney test. Statistical significance was set as p<0.05. Results: The range of motion, double heel rising, and one-leg standing were achieved faster in the control group (p<0.05). However, single-heel rising, repeated single-heel rising, return to previous activity (work, run, and sport), and functional scores showed no statistical difference (p>0.05). Conclusion: Simple and delayed postoperative rehabilitation of acute Achilles tendon rupture without active range of motion exercises showed satisfactory functional results and a low complication rate.

• Journal of English Language & Literature
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• v.57 no.6
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• pp.1089-1109
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• 2011

In an attempt to demonstrate in context of Nietzsche's "overman" (ubermensch) and Heidegger's "Being-in-the-World" (Dasein) the collective human efforts to overcome humanism in crisis, I will provide the ground for the poetics of overcoming, the ground which are based upon the double movements of transhumanism and transnationalism. For this purpose, I will turn to the theories of two distinctive poets who reveal and disreveal their truths about the subjecthood or the subjectivity in terms of overcoming: Christopher Dewdney for posthuman transhumanity and Dionisio D. Martinez for transnational cultural contamination Transhumanism represented by Christopher Dewdney manifests an interfusion of outside and inside, thereby collapsing the boundary between the mind and the world, and provides a breakthrough from the limitedly defined mind to the transhuman perspective of overcoming by using terminalogy and techniques from science and technology. The emerging transhumanism reflects the growing interdependence between humans and bio technologies, and suggests a potential improvement of human beings. The main argument of transhumanism is that we humans can and should continue to develop in all possible directions, by overcoming our human limitations by shedding the body and having the disembodied consciousness which will liberate our mind. Kwame Anthony Appiah's "cultural contamination" is another form of overcoming as well as a way to otherness, a counter-ideal of cultural purity which sustains authentic culture, reversing the traditional binary opposition between enriching authenticity and threatening hybridization. Dionisio Martinez's poetry sublimates the negative side of Appiah's concept of contamination, by redeeming the value of the Appiah's list of the ideal of contamination such as hybridity, impurity, intermingling, the transformation that comes of new and unexpected combinations of human beings, a bit of this and a bit of that is how newness enters the world. When a poetic subject is doubly exiled and doubly homeless away from his/her native homeland and home of native language, one has no more identification with the authentic culture of both home and away, but rather anticipates a new identity as a transnational subject to cross the bridge beyond cultural authenticity and to enter into the field of cultural contamination.

• Clinical Nutrition Research
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• v.12 no.4
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• pp.257-268
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• 2023

Migraine is a common neurological disease correlated with oxidative stress and lipid profile disorders. The present study was designed to determine the effects of Coenzyme Q10 (Co-Q10) supplementation on oxidative status and lipid profile in migraine individuals. This clinical trial was conducted on 84 females aged 18-50 years, diagnosed for episodic migraine according to the International Headache Society. Subjects were randomized to receive either Co-Q10 supplement (400 mg/day) or placebo for 12 weeks. Lipid profile and oxidative stress indices including malondialdehyde (MDA) and total antioxidant capacity (TAC) were measured before and after intervention in both groups. Also, anthropometric indices, dietary intakes, and clinical features were collected. Data analysis was conducted using SPSS version 16. Seventy-seven of the participants, with mean age of 33.70 ± 7.75 years, completed the study. After 12-week intervention, Co-Q10 led to a significant decrease in MDA levels compared to placebo (p = 0.009), with no effect on TAC levels (p = 0.106). A significant increase in serum Co-Q10 concentration and high-density lipoprotein cholesterol (HDL-C) level in Co-Q10 group was observed, but no significant differences were found in other lipid profile variables (low-density lipoprotein cholesterol, triglycerides and total cholesterol). Among anthropometric variables, Co-Q10 only caused a significant reduction in body fat percentage (BFP), but we did not find any significant changes in others. A 12-week Co-Q10 supplementation led to significant improvement in clinical features, BFP, and HDL-C level among migraine individuals.

• Journal of the Korean Society of Radiology
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• v.11 no.7
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• pp.547-553
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• 2017

In the current medical field, lead is widely used as a radiation shield. However, the lead weight is very heavy, so wearing protective clothing such as apron is difficult to wear for long periods of time and there is a problem with the danger of lethal toxicity in humans. Recently, many studies have been conducted to develop substitute materials of lead to resolve these problems. As a substitute materials for lead, barium(Ba) and iodine(I) have excellent shielding ability. But, It has characteristics emitting characteristic X-rays from the energy area near 30 keV. For patients or radiation workers, shielding materials is often made into contact with the human body. Therefore, the characteristic X-rays generated by the shielding material are directly exposured in the human body, which increases the risk of increasing radiation absorbed dose. In this study, we have developed the FLUKA transport code, one of the most suitable elements of radiation transport codes, to remove the characteristic X-rays generated by barium or iodine. We have verified the reliability of the shielding fraction of the structure of the structure shielding by comparing with the MCPDX simulations conducted as a prior study. Using the MCNPX and FLUKA, the double layer shielding structures with the various thickness combination consisting of barium sulphate ($BaSO_4$) and bismuth oxide($Bi_2O_3$) are designed. The accuracy of the type shown in IEC 61331-1 was geometrically identical to the simulation. In addition, the transmission spectrum and absorbed dose of the shielding material for the successive x-rays of 120 kVp spectra were compared with lead. In results, $0.3mm-BaSO_4/0.3mm-Bi_2O_3$ and $0.1mm-BaSO_4/0.5mm-Bi_2O_3$ structures have been absorbed in both 33 keV and 37 keV characteristic X-rays. In addition, for high-energy X-rays greater than 90 keV, the shielding efficiency was shown close to lead. Also, the transport code of the FLUKA's photon transport code was showed cut-off on low-energy X-rays(below 33keV) and is limited to computerized X-rays of the low-energy X-rays. But, In high-energy areas above 40 keV, the relative error with MCNPX was found to be highly reliable within 6 %.

• Journal of Animal Science and Technology
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• v.48 no.2
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• pp.219-226
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• 2006

The wastes (the needle leaves and branches) produced from thinning the forest were fermented under an anaerobic condition (pine silage) to utilize as a forage source of ruminants. An in situ trial was conducted with two ruminally fistulated Korean native cows by 4 replicates (2 bags per cow), and in vivo digestibility of pine silage was estimated with five Korean native steers by 5 replicates in incomplete double turn-over design. In order to investigate feed efficiency and carcass traits, forty eight Korean native bulls were assigned to four treatments (0%, 25%, 50%, 75% of pine silage) with a completely randomized design in 12 pens accommodating 4 animals per pen. The amounts of concentrate and roughage allowed to experimental animals were in the range of 2.5% and 0.6% of body weight, respectively. Animals had freely accessed to mineral block and water in stanchion barn.An in situ crude protein digestibility of the roughage sources when suspended for 48 hrs in the rumen was higher for feeding the pine silage than the rice straw, whereas NDF digestibility was vice versa. No differences between the treatments were observed in in vivo digestibilities of dry matter, crude protein and NDF. Daily body weight gain was significantly (P<0.01) higher for the pine silage substitutions compared with the rice straw feeding except for the 25% silage feeding. The pine silage feeding did not affect feed efficiency.In carcass traits, marbling score tended to be higher for the 50% pine silage treatment than the other treatments while back fat thickness tended to be the thinnest for the rice straw feeding. From these results, it may be recommended to substitute pine silage, as a forage source, for rice straw by 50 percent.

• Proceedings of the Ginseng society Conference
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• 2007.12a
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• pp.57-58
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• 2007

Purpose: Ginseng is a well-known medical plant used in traditional Oriental medicine. Korean red ginseng (KRG) has been known to have potent biological activities such as radical scavenging, vasodilating, anti-tumor and anti-diabetic activities. However, the mechanism of the beneficial effects of KRG on diabetes is yet to be elucidated. The present study was designed to investigate the anti-diabetic effect and mechanism of KRG extract in C57BL/KsJ db/db mice. Methods: The db/db mice were randomly divided into six groups: diabetic control group (DC), red ginseng extract low dose group (RGL, 100 mg/kg), red ginseng extract high dose group (RGH, 200 mg/kg), metformin group (MET, 300 mg/kg), glipizide group (GPZ, 15 mg/kg) and pioglitazone group (PIO, 30 mg/kg), and treated with drugs once per day for 10 weeks. During the experiment, body weight and blood glucose levels were measured once every week. At the end of treatment, we measured Hemoglobin A1c (HbA1c), blood glucose, insulin, triglyceride (TG), adiponectin, leptin, non-esterified fatty acid (NEFA). Morphological analyses of liver, pancreas and white adipose tissue were done by histological observation through hematoxylin-eosin staining. Pancreatic islet insulin and glucagon levels were detected by double-immunofluorescence staining. To elucidate an action of mechanism of KRG, DNA microarray analyses were performed, and western blot and RT-PCR were conducted for validation. Results: Compared to the DC group mice, body weight gain of PIO treated group mice showed 15.2% increase, but the other group mice did not showed significant differences. Compared to the DC group, fasting blood glucose levels were decreased by 19.8% in RGL, 18.3% in RGH, 67.7% in MET, 52.3% in GPZ, 56.9% in PIO-treated group. With decreased plasma glucose levels, the insulin resistance index of the RGL-treated group was reduced by 27.7% compared to the DC group. Insulin resistance values for positive drugs were all markedly decreased by 80.8%, 41.1% and 68.9%, compared to that of DC group. HbA1c levels in RGL, RGH, MET, GPZ and PIO-treated groups were also decreased by 11.0%, 6.4%, 18.9%, 16.1% and 27.9% compared to that of DC group, and these figure revealed a similar trend shown in plasma glucose levels. Plasma TG and NEFA levels were decreased by 18.8% and 16.8%, respectively, and plasma adiponectin and leptin levels were increased by 20.6% and 12.1%, respectively, in the RGL-treated group compared to those in DC group. Histological analysis of the liver of mice treated with KRG revealed a significantly decreased number of lipid droplets compared to the DC group. The control mice exhibited definitive loss and degeneration of islet, whereas mice treated with KRG preserved islet architecture. Compared to the DC group mice, KRG resulted in significant reduction of adipocytes. From the pancreatic islet double-immunofluorescence staining, we observed KRG has increased insulin production, but decreased glucagon production. KRG treatment resulted in stimulation of AMP-activated protein kinase (AMPK) phosphorylation in the db/db mice liver. To elucidate mechanism of action of KRG extract, microarray analysis was conducted in the liver tissue of mice treated with KRG extract, and results suggest that red ginseng affects on hepatic expression of genes responsible for glycolysis, gluconeogenesis and fatty acid oxidation. In summary, multiple administration of KRG showed the hypoglycemic activity and improved glucose tolerance. In addition, KRG increased glucose utilization and improved insulin sensitivity through inhibition of lipogenesis and activation of fatty acid $\beta$-oxidation in the liver tissue. In view of our present data, we may suggest that KRG could provide a solid basis for the development of new anti-diabetic drug.

• Journal of Chest Surgery
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• v.37 no.4
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• pp.313-321
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• 2004

Excellent clinical results of the arterial switch operation and the limited availablity of the intraventricular rerouting has recently made an arterial switch operation to become the therapeutic method of choice for the repair of double-outlet right ventricle (DORV) with subpulmonary ventricular septal defect (VSD). The early and midterm outcomes of arterial switch operation for this anomaly were evaluated. Material and Method: Between August 1994 and July 2002, 13 patients underwent an arterial switch operation for the correction of double-outlet right ventricle with subpulmonary VSD at Dong-A university hospital.. The 50% rule was used to define DORV. Median age and mean body weight were 27 days (range, 3-120 days) and 3.8$\pm$0.7kg (range, 2.92-5.3kg) respectively. Aortic arch anomalies were associated in 6 cases (46.2%), which were all repaired through one-stage operation. The relationship of the great arteries were side-by-side in 8 cases (61.5%) and anteroposterior in 5 (38.5%). Coronary artery patterns were 1 LCx-2R in 6 cases, retropulmonary left coronary artery (LCA) in 6, and intramural LCA in 1 respectively. The enlargement of VSD was required in 1 patient and the patch enlargement of right ventricular outflow tract was performed in another one patient. The Lecompte maneuver was used in all but 3 patients with a side by side relationship of the great arteries. Result: Overall postoperative hospital mortality was 23.1 % (3/13). All operative deaths were occurred in the patients with aortic arch anomalies. There was one late death related to the postoperative complication of the central nerve system during the mean follow-up of 41.3$\pm$30.7 months. Pulmonary valvar stenosis (＞30mmHg of pressure gradient) developed in 1 patient (10%) and left pulmonary artery stenosis in 2 (20%), among them, one required reoperation 52 months after repair. There was an asymptomatic patient with moderate aortic regurgitation. 5-year survival rate including operative deaths was 68.3%. Conclusion: Although the operative mortality is high in the patients with aortic arch anomaly, the arterial switch operation for DORV with supbpulmonary VSD can be performed with low operative mortality and low reoperation rate in the patients Without arch anomaly. The arterial switch operation can be considered a good option for this complex anomaly.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.2
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• pp.315-321
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• 2002

This study was focused on identifying the difference of food preference according to body size of elementary school boys in Daejeon city. In order to measure the food preference, the degree of liking by means of a 5-point Hedonic scale was asked to 198 boys of 5th grade from six schools throughout Daejeon for 144 food items in 17 food groups composed of main dish, side dish and dessert : cooked rice, noodles or breads, as main dish, kimchi, tang.guk.zzigae, gui, zzim, bokeum, fried.pan-fried, jorim, muchim.namul or jangachi, as side dish, fruits, beverage, milk, rice cake or anacks, as dessert and for best preferred taste among five basic. The survey was conducted in rune, 1997 by questionnaires. Overall food preference of the subject was inclined to be higher in most of dessert food : fruits, beverage, milk or snacks, but to be lower in side dishes of Korean conventional food : jangachi, muchim, namul, jorim, kimchi and tang.guk .zzigae. The percentage of boys preferring cocked rice to noodle or bread as main dish was as much almost double in overweight boys as those of underweight or normal weight boys. None of the food group among 17 groups was significantly different in the food preference by body size of the subjects. However, food preference score of overweight group showed a trend to be higher in 11 food groups except less calorie-dense food groups such as fruits, noodles, rice cake, cooked rice, soup and stew and braised food (jorim) than normal or underweight group, and they seemed to prefer especially high-protein and high-fat foods. Being based on 3 points of preference score as the criterion for comparison, underweight group showed higher preference only in fruits group but showed lower preferences in 12 food groups among 17 groups than other groups.