• Journal of the Korean Ceramic Society
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• v.51 no.6
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• pp.554-559
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• 2014

Gadolinium zirconate, $Gd_2Zr_2O_7$, is one of the most promising candidates for replacing yttira-stabilized zirconia (YSZ) in thermal barrier coating (TBC) applications due to its low thermal conductivity and chemical stability at high temperature. In this study, rare-earth zirconate ceramics in the $GdO_{1.5}-ZrO_2$ system with reduced gadolinia contents were fabricated via solid-state reaction as well as hot-pressing at $1800^{\circ}C$. The phase formation, microstructure, and thermo-physical properties of these oxides were examined. The potential application of $GdO_{1.5}-ZrO_2$ ceramics for TBC was also discussed.

• Journal of Engineering Education Research
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• v.12 no.3
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• pp.50-58
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• 2009

A survey was conducted and analyzed for strengthening the employment competitiveness of engineering students. Questionnaires were conducted to students and graduates majoring in mechanical, civil engineering and computer science as well as to small and medium sized industries. It includes the level of satisfaction and requirement to recognize the situation of the students in metropolitan Seoul area. Survey results indicate that for undergraduates and graduates, knowledge of their own majors is most important. However, for industry, the most important factor is the ability of analysis and application, and their personalities. With the results of this survey, it is expected that these discrepancies between industries and students are reduced and the competitiveness of students is strengthened.

• Journal of Oriental Neuropsychiatry
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• v.25 no.4
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• pp.423-434
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• 2014

Objectives: Activated microglia cells play an important role in inflammatory responses in the central nervous system (CNS) which are involved in neurodegenerative diseases. We attempted to determine the anti-inflammatory effects of Cheongnoimyungshin-hwan (CNMSH) in microglia cells. Methods: We examined the effect of CNMSH on the inflammatory responses in BV2 microglia cells induced by lipopolysaccharide (LPS) and explored the mechanism underlying the action of CNMSH. Results: BV2 cells treated with LPS showed an up-regulation of nitric oxide (NO), prostaglandin $PGE_2(PGE_2)$ and interleukin $1{\beta}(IL-1{\beta})$ release, whereas CNMSH suppressed this up-regulation. CNMSH inhibited the induction of COX-2, iNOS and $IL-1{\beta}$ proteins in LPS-treated BV2 cells and blocked the LPS-induced phosphorylation and nuclear translocation of nuclear factor ${\kappa}B(NF-{\kappa}B$). Furthermore, CNMSH attenuated the LPS-induced phosphorylation of extracellular signal-regulated kinase and p38 mitogen activated protein kinase (MAPK), as well as the phosphoinositide 3-kinase (PI3K)/Akt signaling pathway, but did not inhibit the LPS-induced phosphorylation of c-Jun amino terminal kinase. Conclusions: These results suggest that the inhibitory effect of CNMSH on the LPS-induced production of inflammatory mediators and cytokines in BV2 cells is associated with the suppression of the $NF-{\kappa}B$ and PI3KAkt signaling pathways.

• Journal of Korean Medical Science
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• v.33 no.50
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• pp.326.1-326.10
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• 2018

Background: This retrospective study analyzed the causes of failure in the management process from the identification of brain-dead potential organ donors to actual donation in Korea over the past 5 years. Methods: Data of 8,120 potential brain deaths reported to the Korea Organ Donation Agency were used, including information received at the time of reporting, donation suitability evaluation performed by the coordinator after the report, and data obtained from interviews of hospital medical staff and the donor's family. Results: From January 2012 to December 2016, the total number of brain-dead potential organ donors in Korea was 8,120, of which 2,348 (28.9%) underwent organ procurement surgery with designated recipients. While the number of transplant donors has increased over time, the ratio of transplant donors to medically suitable brain-dead donors has decreased. The common causes of donation failure included donation refusal (27.6%), non-brain death (15.5%), and incompatible donation (11.6%); 104 potential donors (7.8%) were unable to donate their organs because they were not pronounced brain dead. Conclusion: The rate of successful organ donation may be increased by analyzing the major causes of failure in the brain-dead organ donation management process and engaging in various efforts to prevent such failures.

• Journal of Korean Medicine Rehabilitation
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• v.29 no.4
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• pp.73-79
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• 2019

Objectives The purpose of this study is to provide Korean version of mild traumatic brain injury assessment tool. Methods The original version of acute concussion evaluation (ACE) was translated into Korean, and it was then back-translated into English without any prior knowledge of ACE. Finally, the pre-final version of Korean version of acute concussion evaluation (K-ACE) was derived. 49 Korean patients who had been diagnosed with mild traumatic brain injury participated in the study and completed K-ACE. Overall, 44 data were used to analyze findings. Validity of the study was assessed based on Concurrent validity. Reliability was also evaluated using Cronbach's ${\alpha}$ and the intraclass correlation coefficient. Results The Cronbach's ${\alpha}$ value for each item presented a proper level of internal consistency with results of 0.711 to 0.893 in two evaluations, respectively. The intraclass correlation coefficient of the retest reliability was marked as 0.892 (95% CI 0.840~0.933). Concurrent validity demonstrated positive correlations between K-ACE and Korean version of postconcussional syndrome questionnaire. Conclusions The K-ACE is concluded as a valid and reliable tool for measuring mild traumatic brain injury and post-concussion symptoms. Upon completion of the follow-up study, the K-ACE will be well-utilized by both clinicians and researchers.

• Physical Therapy Korea
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• v.26 no.1
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• pp.51-59
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• 2019

Background: Chronic low back pain (CLBP) causes morphological changes in muscles, reduces muscle strength, endurance and flexibility, negatively affects lumbar stability, and limits functional activity. Plank exercise strengthens core muscles, activates abdominal muscles, and improves intra-abdominal pressure to stabilize the trunk in patients with CLBP. Objects: We investigated the effect of plank exercise on abdominal muscle thickness and disability in patients with CLBP. Methods: We classified 33 subjects into 2 groups: An experimental (n1=17) and a control group (n2=16). Patients in the experimental group participated in plank exercise and those in the control group participated in stretching exercise. Patients in both groups attended 20-minute exercise sessions thrice a week for 4 weeks. Abdominal muscle thickness in each subject was evaluated ultrasonographically, and disabilities were assessed using the Oswestry disability index (ODI). Results: Four weeks later, abdominal muscle thickness showed a significant increase over baseline values in both groups (p<.05). Patients in the experimental group reported a more significant increase in the thickness of the external oblique muscle than that in the control group (p<.05). ODI scores in the experimental group were significantly lower after intervention than before intervention (p<.05). Conclusion: Plank exercise increases the thickness of the external oblique muscle and reduces disability secondary to mild CLBP. Therefore, plank exercise is needed to improve lumbar stability and functional activity in patients with mild CLBP.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.73-73
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• 2019

전나무속(Abies Miller, 1754)은 지구상에서 북반구를 중심으로 50여 종이 현존하고 있다. 전나무속은 주로 높은 고도의 산지 또는 수목 한계선 주변에 자연적 분포지를 형성하고 있으며, 국내에는 전나무(A. holophylla), 분비나무(A. nephrolepis) 및 구상나무(A. koreana), 총 3종이 자생하고 있다. 하지만 국내에 자생하는 3종의 경우도 쇠퇴가 급격히 진행되고 있다. 특히 대한민국 특산식물인 한라산의 구상나무는 IUCN Redlist 상의 'Threatened species' category 종으로 등재되어 있을 뿐만 아니라 구상나무 어린 나무(치수)의 수가 급격히 줄어 우리 사회에서 문제가 직면한 '저출산 고령화 사회'와 유사하다고 할 수 있다. 하지만, 구상나무의 어린 나무에 관한 연구가 미비한 실정이다. 게다가 선행연구에서도 어린 나무의 기준이 모호하다. 따라서 본 연구는 구상나무 등 국내 자생하는 구상나무 천연묘의 기준을 정립하여 추후 진행되는 구상나무 등 전나무속 어린 나무에 관한 연구에 표준화를 유도할 수 있을 것으로 기대된다. 우선, 국내.외 소나무과 어린나무에 관한 논문을 정리 및 분석하였고, 구상나무 어린나무가 자생하는 숲의 구조(제주조릿대 등) 및 환경(암석노출도) 등)에 적절한 높이와 아린흔의 갯수를 참고로 기준안을 제시해 보고자 한다. 본 연구의 기준안은 선행연구에서 조사된 구상나무 어린나무 3,138개체의 높이 및 아린흔 갯수를 토대로 구분해볼 수 있었다. 우선, 높이에 대한 기준은 1년생묘(당해묘, 5cm 미만)-유묘(5cm~10cm 미만)-성묘(대묘, 10cm~30cm 미만)-치수(30cm~100cm 미만) cf.전생치수-유목(100cm 이상) 5단계로 구분되었다. 아린흔 갯수에 대한 기준도 또한 1년생묘(1개)-유묘(2개~6개)-성묘(대묘, 7개~15개)-치수(16개~20개) cf.전생치수-유목(21개 이상) 5단계로 구분되었다.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.74-74
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• 2019

한라산은 남한에서 가장 높은 산으로 해발고도는 1,950m이고 그 면적은 약 9,100ha로 대한민국 최대의 섬제주의 중심에 자리하고 있다. 한라산은 특산식물이 36종이나 발견되어 국내 외적으로 생물적인 가치와 보전적인 가치를 인정받아온 곳이다. 본 연구에서는 한라산 성판악에서 백록담으로 이어지는 동사면의 해발고도 1,500m 부근의 진달래밭대피소 인근에 위치한 5ha 장기생태 연구 지역 식생조사를 통해서 조사된 자생 식물종을 정리하였다. 관속식물은 31과 44속 56종 등 총 56분류군으로 조사되었으며, 조사지역에서 확인된 산림청지정 희귀식물은 구상나무(LC), 주목(VU), 섬매발톱나무(DD), 개족도리풀(LC), 시로미(VU), 게박쥐나물(LC), 사철란(LC) 등 7분류군이 확인되었고, 특산식물로는 구상나무, 족도리풀, 제주조릿대, 산제비란 등 4분류군이 확인되었다. 식물구계학적 특정식물은 I등급은 일엽초, 윤노리나무, 야광나무, 큰천남성 등 6분류군, II등급으로는 두루미꽃, 홍괴불나무, 마가목, 산개벚지나무, 다람쥐꼬리 등 10분류군, III등급은 만년석송, 구상나무, 애기괭이밥, 호자덩굴 등 8분류군, IV등급은 시로미 그리고 V등급은 설앵초가 각각 1분류군으로 조사되었다. 한라산 아고산대의 대표 우점종인 구상나무는 특산식물이자, 식물구계학적 특정식물 III등급이며, 산림청지정 희귀식물 약관심종으로 추가 연구를 통하여 보전관리방안이 수립되어야 하는 것으로 판단된다.

• Korean Chemical Engineering Research
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• v.57 no.3
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• pp.372-377
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• 2019

Leaching ($60^{\circ}C$, 5 min) and wet torrefaction ($200^{\circ}C$, 5 min) of empty fruit bunch (EFB) were carried out to improve the fuel properties; each liquid fraction was reused for leaching and wet torrefaction, respectively. In the leaching process, potassium was effectively removed because the leaching solution contained 707.5 ppm potassium. Inorganic compounds were accumulated in the leaching solution by increasing the reuse cycle of leaching solution. The major component of the leached biomass did not differ significantly from the raw material (p-value < 0.05). Inorganic compounds in the biomass were more effectively removed by sequential leaching and wet torrefaction (61.1%) than by only the leaching process (50.1%) at the beginning of the liquid fraction reuse. In the sequential leaching and wet torrefaction, the main hydrolysate component was xylose (2.36~4.17 g/L). This implied that hemicellulose was degraded during wet torrefaction. As in the leaching process, potassium was effectively removed and the concentration was accumulated by increasing the reuse cycle of wet torrefaction hydrolysates. There was no significant change in the chemical composition of wet torrefied biomass, which implied that fuel properties of biomass were constantly maintained by the reuse (four times) of the liquid fraction generated from leaching and wet torrefaction.

• Korean Journal of Anesthesiology
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• v.71 no.6
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• pp.440-446
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• 2018

Background: The aim of this study was to evaluate aprepitant in combination with palonosetron as compared to palonosetron alone for the prevention of postoperative nausea and vomiting (PONV) in female patients receiving fentanyl-based intravenous patient-controlled analgesia (IV-PCA). Methods: In this randomized single-blinded study, 100 female patients scheduled for elective surgery under general anesthesia were randomized to two groups: Group AP (80 mg aprepitant plus 0.075 mg palonosetron, n = 50) and Group P (0.075 mg palonosetron, n = 50). The patients in group AP received 80 mg aprepitant per oral 1-3 h before surgery, while all patients received 0.075 mg palonosetron after induction of standardized anesthesia. All patients had postoperative access to fentanyl-based IV-PCA. The incidence of nausea and vomiting, use of rescue medication, and severity of nausea were evaluated at 6 and 24 h after surgery. Results: The incidence of nausea (54%) and vomiting (2%) in group AP did not differ significantly from that in group P (48% and 14%, respectively) during the first 24 h after surgery (P > 0.05). Patient requirements for rescue medication in group AP (29%) were similar to those in group P (32%) at 24 h after surgery (P > 0.05). There was no difference between the groups in severity of nausea during the first 24 h after surgery (P > 0.05). Conclusions: Aprepitant combined with palonosetron did not reduce the incidence of PONV as compared to palonosetron alone within 24 h of surgery in women receiving fentanyl-based IV-PCA.