• 대한금속재료학회지
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• 제46권9호
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• pp.545-553
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• 2008

Dynamic deformation behavior of ultra-fine-grained pure coppers fabricated by equal channel angular pressing (ECAP) was investigated in this study. Dynamic torsional tests were conducted on four copper specimens using a torsional Kolsky bar, and then the test data were analyzed by their microstructures and tensile properties. The 1-pass ECAP'ed specimen consisted of fine dislocation cell structures elongated along the ECAP direction, which were changed to very fine, equiaxed subgrains of 300~400 nm in size as the pass number increased. The dynamic torsional test results indicated that maximum shear stress increased with increasing ECAP pass number. Adiabatic shear bands were not found at the gage center of the dynamically deformed torsional specimen of the 1- or 4-pass ECAP'ed specimen, while some weak bands were observed in the 8-pass ECAP'ed specimen. These findings suggested that the grain refinement according to the ECAP was very effective in strengthening of pure coppers, and that ECAP'ed coppers could be used without serious reduction in fracture resistance under dynamic torsional loading as adiabatic shear bands were hardly formed.

• Journal of Trauma and Injury
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• 제36권3호
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• pp.224-230
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• 2023

Purpose: Patients with penetrating injuries are at a high risk of mortality, and many of them require emergency surgery. Proper triage and transfer of the patient to the emergency department (ED), where immediate definitive treatment is available, is key to improving survival. This study aimed to evaluate the epidemiology and outcomes of patients with penetrating torso injuries in Incheon Metropolitan City. Methods: Data from trauma patients between 2014 and 2018 (5 years) were extracted from the National Emergency Department Information System. In this study, patients with penetrating injuries to the torso (chest and abdomen) were selected, while those with superficial injuries were excluded. Results: Of 66,285 patients with penetrating trauma, 752 with injuries to the torso were enrolled in this study. In the study population, 345 patients (45.9%) were admitted to the ward or intensive care unit (ICU), 20 (2.7%) were transferred to other hospitals, and 10 (1.3%) died in the ED. Among the admitted patients, 173 (50.1%) underwent nonoperative management and 172 (49.9%) underwent operative management. There were no deaths in the nonoperative management group, but 10 patients (5.8%) died after operative management. The transferred patients showed a significantly longer time from injury to ED arrival, percentage of ICU admissions, and mortality. There were also significant differences in the percentage of operative management, ICU admissions, ED stay time, and mortality between hospitals. Conclusions: Proper triage guidelines need to be implemented so that patients with torso penetrating trauma in Incheon can be transferred directly to the regional trauma center for definitive treatment.

• 융합보안논문지
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• 제24권1호
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• pp.43-49
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• 2024

교육(education)과 기술(technology)의 융합이 강조되면서 에듀테크가 교육 현장에 적용되어 다양한 매체와 학습 상황 속에서 학습자 중심의 맞춤형 교육환경을 제공하고 있다. 본 논문에서는 사이버보안 교육 현장에서 사물인터넷 보안 교육을 위한 에듀테크 기반의 교육용 교구를 제작하기 위하여 하나의 보드(Board) 내에서 이중 MCU를 기반으로 공격과 방어가 각각 수행될 수 있도록 하드웨어를 설계하였으며, 사물인터넷의 다양한 센서를 활용하기 위하여 모듈형으로 설계하여 제시하였다. 교육측면에서 에듀테크를 활용한 사이버보안 교육은 실제 물리적인 교구를 활용함으로써 교육에 대한 호감을 키우고, 임베디드 하드웨어와 소프트웨어, 센서 네트워크 등 기존 교육에서 다루기 어려운 분야에 대한 보안 교육 환경을 간단하게 구성하기 위하여 IoT 보안 교육용 하드웨어 설계시 참고가 될 수 있도록 연구 제안한다.

• Asian-Australasian Journal of Animal Sciences
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• 제24권6호
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• pp.781-790
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• 2011

The effects of seedtime and maturity stage on nutritive value of five maize stover varieties, including conventional maize (Kexiangyu 11, CM), fodder maize (Huqing 1, FM), high oil maize (Gaoyou 115, HOM), sweet maize (Kexiangtianyu 1, SM) and waxy maize (Kexiangluoyu 1, WM), were examined based on chemical composition, in vitro gas production and in situ incubation techniques. Maize stover was sampled at d 17 and d 30 after tasseling, and designated as maturity stage 1 and stage 2, respectively. The average dry matter (DM) organic matter (OM), crude protein (CP) and fiber contents were the greatest for HOM, SM and FM, respectively. CM had the highest in vitro organic matter disappearance (IVOMD) and volatile fatty acid (VFA) concentration. The highest ammonia nitrogen ($NH_3$-N) concentration in the incubation solution, and effective degradability of DM ($ED_{DM}$) and neutral detergent fiber ($ED_{NDF}$) were observed in SM. Advanced maturity stage increased (p<0.05) DM content, $ED_{DM}$ and $ED_{NDF}$, but decreased (p<0.05) OM and CP contents, and decreased (p<0.05) b and a+b values, IVOMD and molar proportion of valerate in the incubation solution for maize stover. Maize sown in summer had greater (p<0.05) OM content, but lower DM, CP, neutral detergent fiber (NDF) and acid detergent fiber (ADF) content compared with maize sown in spring. Maize sown in summer had greater (p<0.001) IVOMD, $NH_3$-N concentration in the incubation solution and $ED_{NDF}$, but lower (p<0.01) ratio of acetate to propionate compared to maize sown in spring. The interaction effect of variety${\times}$seedtime was observed running through almost all chemical composition, in vitro gas production parameters and in situ DM and NDF degradability. The overall results suggested that SM had the highest nutrient quality, and also indicated the possibility of selecting maize variety and seedtime for the utilization of maize stover in ruminants.

• 약학회지
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• 제38권2호
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• pp.140-148
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• 1994

${\beta}-Lactamase$ stability, chemotherapeutic activity, and pharmacokinetics of 7-[(Z)-2-(2-aminothiazole-4-yl)-2-methoxyiminoacetamido]-3-[4-(2-pyridyl)piperazinyl]thiocarbonylthiomethyl-3-cephem-4-carboxylic acid(CEN1), 7-[(Z)-2-(2-aminothiazole-4-yl)-2-methoxyiminoacetamido]-3-[4-(2-pyrimidyl)piperazinyl]thiocarbonylthiomethyl-3-cephem-4-carboxylic acid(CEN2), pivaloyloxymethyl-7-[(Z)-2-(2-aminothizaole-4-yl)-2-methoxyiminoacetamido]-3-[4-(2-pyridyl)piperazinyl]thiocarbonyl-thiomethyl-3-cephem-4-carboxylate(CEN1P), and pivaloyloxymethyl-7-{(Z)--2-(2-aminothizaole-4-yl)-2-methoxyiminoacetamido]-3-[4-(2-pyridyl)piperazinyl]thiocarbonyl-thiomethyl-3-cephem-4-carboxylate(CEN2P) were examined. CEN1, CEN2, CEN1P, and CEN2P were very stable to the ${\beta}-lactamase$ obtained from three strains(Enterobacter cloacae P99, Escherichia coli TEM, and Citrobacter freundii). Chemotherapeutic activities$(ED_{50})$ of CEN2 and CEN2P against experimental systemic infections due to Streptococcus pyogenes 77A and Escherichia coli 078 were superior to those of CEN1 and CEN1P, respectively. The $ED_{50}$ values of CEN1, CEN2 were 5.82 mg/kg, 0.89 mg/kg(s.c., S. pyogenes 77A) while those of CEN1P, CEN2P were 14.56mg/kg, 6.40mg/kg(p.o., S. pyogenes 77A), respectively. The pharmacokinetics of CEN1, CEN2, CEN1P, and CEN2P were investigated in mice and rats. In mice, peak blood levels of $1.25\;{\mu}g/ml$ were recorded within 20 min after oral administration of a single dose equivalent to 40 mg/kg CEN1P. Cmax of CEN1P was much higher than that of CEN1 in mice and rats. Oral absorption of CEN2P was much higher than that of CEN2.

• Journal of Preventive Medicine and Public Health
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• 제51권6호
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• pp.265-274
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• 2018

Objectives: A positive association between air pollution and both the incidence and prevalence of diabetes mellitus (DM) has been reported in some epidemiologic and animal studies, but little research has evaluated the relationship between air pollution and diabetic coma. Diabetic coma is an acute complication of DM caused by diabetic ketoacidosis or hyperosmolar hyperglycemic state, which is characterized by extreme hyperglycemia accompanied by coma. We conducted a time-series study with a generalized additive model using a distributed-lag non-linear model to assess the association between ambient air pollution (particulate matter less than $10{\mu}m$ in aerodynamic diameter, nitrogen dioxide [$NO_2$], sulfur dioxide, carbon monoxide, and ozone) and emergency department (ED) visits for DM with coma in Seoul, Korea from 2005 to 2009. Methods: The ED data and medical records from the 3 years previous to each diabetic coma event were obtained from the Health Insurance Review and Assessment Service to examine the relationship with air pollutants. Results: Overall, the adjusted relative risks (RRs) for an interquartile range (IQR) increment of $NO_2$ was statistically significant at lag 1 (RR, 1.125; 95% confidence interval [CI], 1.039 to 1.219) in a single-lag model and both lag 0-1 (RR, 1.120; 95% CI, 1.028 to 1.219) and lag 0-3 (RR, 1.092; 95% CI, 1.005 to 1.186) in a cumulative-lag model. In a subgroup analysis, significant positive RRs were found for females for per-IQR increments of $NO_2$ at cumulative lag 0-3 (RR, 1.149; 95% CI, 1.022 to 1.291). Conclusions: The results of our study suggest that ambient air pollution, specifically $NO_2$, is associated with ED visits for diabetic coma.

• 대순사상과 동아시아종교
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• 제1권2호
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• pp.171-173
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• 2022

• 대순사상과 동아시아종교
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• 제3권1호
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• pp.155-157
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• 2023

• Archives of Pharmacal Research
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• 제29권12호
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• pp.1080-1085
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• 2006

A series of 8-alkoxy-4,5-dihydro-[1,2,4]triazole[4,3-a]quinoline-1-one derivatives were synthesized using 7-hydroxy-3,4-dihydro-2(1H)-quinolone as the starting material. Their anticonvulsant activities were evaluated by the maximal electroshock test (MES) and the subcutaneous pentylenetetrazole test (sc-PTZ), and their neurotoxicities were measured by the rotarod neurotoxicity test (Tox). The tests demonstrated that 8-hexyloxy-4,5-dihydro-[1.2.4]triazole[4.3-a]quinoline-1-one (4e) and 8-heptyloxy-4,5-dihydro-[1,2,4]triazole[4, 3-a]quinoline-1-one (4f) were the most potent anticonvulsants, with 4e having $ED_{50}$ values of 17.17 mg/kg and 24.55 mg/kg and protective index ($PI=TD_{50}/ED_{50}$) values of 41.9 and 29.3 in the MES and sc-PTZ tests, respectively, and 4f having $ED_{50}$ values of 19.7 mg/kg and 21.2 mg/kg and PI values of 36.5 and 33.9 in the MES and sc-PTZ tests, respectively. The PI values of 4e and 4f were many fold better than that of the marketed drugs phenytoin, carbamazepine, phenobarbital and valproate, which have PI values in the range of 1.6-8.1 in the MES test and <0.22-5.2 in the sc-PTZ test. Structure-activity relationships were also discussed.

• Clinical and Experimental Reproductive Medicine
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• 제35권1호
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• pp.61-67
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• 2008

목 적: Glucocorticoid가 황체용해에 미치는 효과의 기전의 일부를 면역 조직학적 연구를 통해 알아보고자 하였다. 연구방법: 8주령의 Rat 암컷 30마리 대조군, 덱사메타손 0.1 mg 투여군 및 덱사메타손 1mg 투여군의 3군으로 나누어 황체용해의 차이와 대식세포의 침투여부를 비교하기 위하여 광학현미경을 이용하여 계수하였다. 결 과: TUNEL 면역염색 결과 덱사메타손 0.1 mg 투여군과 1 mg 투여군 모두에서 대조군에 비해 황체용해의 비율이 현저히 감소하였고, ED1 면역염색 결과 덱사메타손 1 mg 투여군에서 대식세포의 황체 내 침투가 현저히 억제된 것으로 나타났다. ED1 면역염색 결과 덱사메타손 1 mg 투여군에서 대식세포의 면역반응성이 대조군에 비해 감소되어 나타났다. 결 론: 덱사메타손은 직접 황체세포에 작용하여 세포자멸사를 억제한다. 또한 대량 투여했을 때는 대식세포의 황체 내 침투를 억제하거나 황체 내에 이미 존재하는 대식세포의 활성화를 억제함으로써 황체용해를 억제한다.