• 한국지반공학회논문집
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• 제23권3호
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• pp.89-100
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• 2007

본 논문과 함께 제출한 논문에서는 미시역학 기반의 새로운 탄소성 모델의 정식화에 대해 설명하였다. 본 논문에서는 사질토 변형의 탄성 및 탄소성 거동을 미시역학에 근거하여 자세히 분석하였다. 모델에 필요한 변수 평가를 위한 과정을 제시하였다. 등방 및 삼축 압축 시험에서 나타난 사질토의 탄성 거동을 분석한 결과, 직교 이방 탄성계수의 응력 종속성은 미시적 수직 강성에서 나타난 수직 접촉력의 거듭제곱 함수 형태가 반영되어 나타나며, 삼축 압축 응력 상태에서는 조직 이방성의 변화가 응력 종속성에 영향을 미침을 알 수 있었다. 미시역학적 해석을 통해 소성 변형이 매우 낮은 변형률 수준에서도 발현되며, 변형 중 사질토 강성의 비선형적 감소는 접촉점에서의 접선 방향 소성 변형에 의해 나타남을 밝혔다.

• Journal of Preventive Medicine and Public Health
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• 제56권3호
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• pp.272-281
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• 2023

Objectives: Young mothers are vulnerable to postpartum depression due to role transition-related stress. Understanding the causes underlying these stressors is essential for developing effective interventions. Methods: This study analyzed the 2018 Indonesian Basic Health Research data. The Mini International Neuropsychiatric Interview was used to assess postpartum depression symptoms in mothers aged 15-24 years with infants aged 0-6 months. In 1285 subjects, the risk factors for postpartum depression were evaluated using multivariate logistic regression. Results: The overall prevalence of depression in the 6 months postpartum was 4.0%, with a higher prevalence in urban areas (5.7%) than in rural areas (2.9%). Urban and rural young mothers showed distinct postpartum depression risk factors. In urban areas, living without a husband (odds ratio [OR], 3.82; 95% confidence interval [CI], 1.24 to 11.76), experiencing preterm birth (OR, 4.67; 95% CI, 1.50 to 14.50), having pregnancy complications (OR, 3.03; 95% CI, 1.20 to 7.66), and having postpartum complications (OR, 5.23; 95% CI, 1.98 to 13.80) were associated with a higher risk of postpartum depression. In rural areas, postpartum depression was significantly associated with a smaller household size (OR, 3.22; 95% CI, 1.00 to 10.38), unwanted pregnancy (OR, 4.40; 95% CI, 1.15 to 16.86), and pregnancy complications (OR, 3.41; 95% CI, 1.31 to 8.88). Conclusions: In both urban and rural contexts, postpartum depression relates to the availability of others to accompany young mothers throughout the postpartum period and offer support with reproductive issues. Support from the family and the healthcare system is essential to young mothers' mental health. The healthcare system needs to involve families to support young mothers' mental health from pregnancy until the postpartum period.

• 환경생물
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• 제40권3호
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• pp.275-280
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• 2022

부유물질은 수생생물의 성장과 생존에 중요한 역할을 한다. 본 논문은 cyst에서 부화한 Artemia 유생(branchiopoda), 조간대에서 채집한 T. west (copepod)와 H. koreanus (amphipoda)를 사용하여 96시간 동안 부유물질에 노출된 생물의 생존 영향을 규명하였다. 실험 결과 Artemia 유생과 T. west의 생존율은 50.0mg L^-1 이상의 부유물질 농도에 영향을 받지 않으나 H. koreanus는 부유물질 농도가 증가함에 따라 낮은 생존율을 보였다(p<0.05). 결론적으로 50.0mg L^-1 이상의 부유물질에 지속적으로 노출된 Artemia 유생과 T. west는 미세한 생태 스트레스의 영향을 받지만 H. koreanus는 생존 가능한 내성범위를 벗어나 사망한 개체가 증가할 것으로 판단된다.

• Composites Research
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• 제19권1호
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• pp.1-8
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• 2006

적층 복합재료에 가해지는 저속충격에 의한 동적 거동 및 손상의 예측은 복합재 구조물의 설계에 중요한 문제가 되고 있다. 특히 저속충격에 의한 손상을 기술하기 위하여 적층판 내의 면내응력 뿐만 아니라 층간응력이 중요한 역할을 하는데, 기존의 전통적인 접근 방법은 이들을 효과적으로 기술하지 못하는 단점이 있다 본 논문에서는 이러한 동적거동 및 손상을 기술하기 위한 수치해석 모델로서 내부 미시구조를 고려한 직접수치모사(DNS)방법을 이용하여 DNS 모델을 구성하였다. 그리고 이를 저속충격 문제에 적용하여 저속충격에 의한 동적 거동 및 재료내의 층간응력 해석을 미시적으로 접근하였다. 이때 기존의 거시적인 접근 방법에 따른 균질모델의 결과와 비교 해석을 보였다. 한편 복합재료 적층판의 효율적인 저속충격해석을 위하여 DNS 개념을 적용한 멀티스케일 모델을 개발하여 기존의 균질화된 모델에서 보일 수 없었던 충격 부위의 국부적인 동적 거동을 효과적으로 기술하였다.

• 대한중풍순환신경학회지
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• 제15권1호
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• pp.1-12
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• 2014

■ Objectives This study was designed to investigate the effects of Ephedra Herba hexane fraction on lipid levels in serum and lipid accumulation in liver tissue in Hyperlipidemic mice. ■ Methods Hyperlipidemia was induced by providing high fat diet for 4 weeks. Normal group was provided with normal diet. CTL groupwas provided with high fat diet. Ephedra Herba hexane fraction group was provieded with high fat diet and administered orally in the concentration of 1.5mg/kg body weight/day for 2 weeks. In this experiment, effects on total cholesterol, HDL-cholesterol, triglyceride, AST, ALT, fasting blood glucose in serum were measured. In addition histopathological changes in liver tissue were also observed. ■ Results Ephedra Herba hexane fraction did not affects weight gain, serum AST and ALT in hyperlipidemic mice. Oral administration of Ephedra Herba hexane fraction lowered levels of total cholesterol and triglyceride, which were elevated by induction of hyperlipidemia. In addition, Ephedra Herba hexane fraction group showed downward tendency of lipid accumulation compared with CTL group. Finally, administration of Ephedra Herba hexane fraction lowered fasting blood glucose significantly. And Ephedra Herba hexane fraction also ameliorates anti-oxidative stress systems in internal organs which play key role in disease prevention. ■ Conclusion These results suggest that Ephedra Herba hexane fraction can prevent lipid accumulation in liver tissue through regulation of dyslipidemia and hyperglycaemia.

• Journal of Hospice and Palliative Care
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• 제25권2호
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• pp.55-65
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• 2022

Caring for patients with cancer is highly stimulating and rewarding, attracting health professionals to the field who enjoy the challenge of managing a complex illness. Health professionals often form close bonds with their patients as they confront ongoing disease or treatment impacts, which may be associated with multiple losses involving function and/or eventual loss of life. Ongoing exposure to patient loss, along with a challenging work setting, may pose significant stress and impact health professionals' well-being. The prevalence rates of burnout and compassion fatigue (CF) are significant, yet health professionals have little knowledge on these topics. A 6-week continuing education program consisting of weekly small-group video-conferencing sessions, case-based learning, and an online community of practice was delivered to health care providers providing oncology care. Program content included personal, organization and team-related risk and protective factors associated with CF, grief models, and strategies to mitigate against CF. Content analysis was completed as part of the program evaluation. In total, 189 participants (93% nurses) completed the program, which was associated with significant improvements in confidence and knowledge of CF and strategies to support self and team resilience. Qualitative themes and vignettes from experiences with the program are presented. Key themes included knowledge gaps, a lack of support related to CF and strategies to support resilience, organization-and team-based factors that can inhibit expression about the impacts of clinical work, the health professional as a "person" in caregiving, and the role of personal variables, self-skill practices, and recommendations for education and support for self and teams.

• 운동영양학회지
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• 제13권2호
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• pp.161-167
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• 2009

The purpose of this study was to investigate whether two different exercises, acute exhaustive exercise and long-term endurance exercise training could affect to the expression of Mn-SOD, HSP70, and PPAR-γ protein in myocardium. The Wistar-Kyoto rats(n=24, 4 weeks) were used and randomly divided into 3 groups; endurance exercise training group (EET, n=8), acute exhaustive exercise group (AEE, n=8) or control group (CON, n=8). EET performed treadmill exercise for 12 weeks (5 days/week, 30~60 min/day). AEE exercised treadmill running (speed increased gradually to 14-26 m/min, 60 min ±10min) until exhausted when EET finished the program. Then, all the rats were sacrificed 48 hours rest at least after the last session of their own exercise program. Hearts were isolated and then the expression of Mn-SOD, HSP70, and PPAR-γ were analyzed by western blotting. One-way repeated ANOVA was used and p value under 0.05 was considered as statistical significance. The results were followed as; the expression of Mn-SOD of AEE was decreased compared with CON. However, the expression of Mn-SOD of EET was increased compared with CON. There was significant difference between AEE and EET in the expression of Mn-SOD. The expressions of HSP70 and PPAR-γ in the both AEE and EET were significantly increased compared with CON. In conclusion, acute exhaustive exercise might induce oxidative stress wheres endurance exercise training could ameliorate the oxidative conditions by increase of Mn-SOD, HSP70, and PPAR-γ. Therefore, we suggested that endurance exercise training could enhance the complementary antioxidant system and improve to prevent apoptosis. Further, a long-term moderat aerobic exercise program might play a important role in mitochondrial biogenesis in the heart.

• 부식과 방식
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• 제12권1호
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• pp.30-38
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• 2013

원전의 구조적 건전성에 문제가 될 수 있는, 오스테나이트계 합금의 환경조장균열(EAC)에 대한 거동을 실험적인 결과와 문헌 조사를 통해 분석하였다. 일차측 환경에서 주기적인 반복하중을 받을 때에는 기계적인 피로균열에 더해 수소유기균열이나 동적변형시효 등으로 인한 가속화 메커니즘을 통해 피로수명 감소가 나타났다. 따라서 EAF에 대한 저항성은 전반적인 부식저항성이 우수한 니켈기합금이 스테인리스강보다 크게 나타났다. 그러나 일정한 하중을 받을 때에는 내부산화에 의해 국부적인 취약부인 입계로의 빠른 균열의 생성과 진전이 나타나 일차수 응력부식균열(PWSCC)이라는 형태로 발생한다고 여겨진다. 이때는 니켈-크롬의 비율이 내부산화 저항성에 영향을 미쳐, 비율이 낮은 스테인리스강은 높은 저항성을 가지고, 비율이 높은 니켈기합금은 낮은 저항성을 가진다. 그러나 아직 이러한 균열 메커니즘에 대한 명확한 이해가 부족하므로, 명확히 규명하기 위해서는 추가적인 연구가 필요하다.

• 영어영문학
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• 제57권6호
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• pp.1151-1171
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• 2011

Conrad's novels, specifically the Lingard Trilogy-Almayer's Folly, An Outcast of the Islands, and The Rescue-and Lord Jim, set in the Southeast Asian or Malay Archipelago can be considered travel literature that played a significant role in British imperial expansion. Conrad's Malay novels were based not only on his experience in the region during his commercial journey but also on information from earlier travel writings about the Malays and their customs, including James Brooke's journals. The English traders in Conrad's novels, namely Lingard and Jim, were partly modeled on Brooke, the White Rajah, who founded and ruled the English colony on the northwest of Borneo in the 1840s. The white traders in Conrad's novels, who act as enlightened rulers, represent the British commercial expansionism, which was obscured by the phenomenon of the civilizing mission in the late nineteenth century. On the other hand, the colonial official Clifford's tales and novels about British Malaya demonstrate the typical travel accounts of the late nineteenth century that stress the civilizing mission over commercial exploitation. The concept of the enlightening mission was rooted in evolutionary anthropological thinking, which developed as part of the natural history in the early nineteenth century. In fact, the development of natural history, stimulating British expansion in search of commercially exploitable resources and lands, enabled travel writing as the collection of natural knowledge to become a profitable business. In Conrad, the white characters are mainly traders acting as colonial rulers, while in Clifford, they are scientific rulers with their commercial interests rarely apparent. In sum, Conrad's novels reveal that the new imperialism of the civilizing mission is still a commercial one, which disturbs rather than contributes to the imperial expansion-in contrast to other travel literature such as Clifford's.

• 대한수의학회지
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• 제63권4호
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• pp.40.1-40.7
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• 2023

To optimize the most efficient method for porcine in vitro maturation (IVM), we compared the effects of supplementing extracellular vesicles (EVs) derived from porcine follicular fluid (pFF). The cumulus oocyte complexes were grouped into 4 groups with different supplementations as following: pFF (G1), pFF-depleted EVs (G2), EVs (G3) and control (G4) groups. After IVM with different supplementations, maturation rates and the developmental competences of porcine oocytes and blastocyst development were investigated. Additionally, glutathione (GSH) and reactive oxygen species (ROS) levels were measured in mature oocytes. The EVs were isolated and characterized with cryo-TEM and nanoparticle tracking analysis. The pFF significantly affected the maturation rate, whereas the presence of EVs did not show notable difference in the maturation rates. Although there were numerical increases in the measured parameters in EV and pFF-depleted EVs groups, no significant differences were observed between them. The EV group showed similar oocyte maturation rate for both positive and negative control groups. The GSH was not different among the groups, but ROS levels were significantly lower in pFF-supplemented group when compared with other groups with the highest level in the control group. G2 group wasn't significantly different G1 and G3 group. G3 group wasn't significantly different from G2 and G4 group. This suggests that EVs in IVM medium which probably effected partially to protect against oxidative stress and potentially enhance the quality of oocytes. This study indicates that the EVs in pFF play a significant role in improving the efficiency of oocyte maturation in porcine.