• Asian-Australasian Journal of Animal Sciences
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• 제15권12호
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• pp.1798-1807
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• 2002

This study was conducted to investigate lactobacillus salivarius subsp. salivarius having probiotic properties to be used as the health adjuncts with fermented milk products. Acid- and bile-tolerant lactobacillus salivarius subsp. salivarius was isolated with lactobacilli MRS broth from faeces of 80 healthy persons (infants, children and adults). It was used as a probiotic strain in fermented milk products. The pH of fermented milk decreased from pH 6.7 to 5.0 and titratable acidity increased from 0.3% to 1.0% by L. salivarius subsp. salivarius (isolation strain 20, 35, and 37), when incubated for 36 h at 37$^{\circ}C$. The number of viable cell counts of fermented milk was maximized at this incubation condition. The SDS-PAGE evidenced no significant change of casein but distinct changes of whey protein were observed by isolated L. salivarius subsp. salivarius for titratable acidity being incubated by 0.9-1.0% at 37$^{\circ}C$. All of the strains produced 83.43 to 131.96 mM of lactic acid and 5.39 to 26.85 mM of isobutyric acid in fermented products. The in vitro culture experiment was performed to evaluate ability to reduce cholesterol levels and antimicrobial activity in the growth medium. The selected L. salivarius subsp. salivarius reduced 23-38% of cholesterol content in lactobacilli MRS broth during bacterial growth for 24 h at 37$^{\circ}C$. All of the isolated L. salivarius subsp. salivarius had an excellent antibacterial activity with 15-25 mm of inhibition zone to E. coli KCTC1039, S. enteritidis KCCM3313, S. typhimurium M-15, and S. typhimurium KCCM40253 when its pH had not been adjusted. Also, all of the isolated L. salivarius subsp. salivarius had partial inhibition zone to E. coli KCTC1039, E. coli KCTC0115 and S. enteritidis KCCM3313 when it had been adjusted to pH 5.7. The selected strains were determined to have resistances of twelve antibiotic. Strains 27 and 35 among the L. salivarius subsp. salivarius showed the highest resistance to the antibiotics. These results indicated that some of the L. salivarius subsp. salivarius (strain 27 and 35) are considered as effective probiotic strains with a potential for industrial applications, but the further study is needed to establish their use as probiotics in vivo.

• Asian Pacific Journal of Cancer Prevention
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• 제14권8호
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• pp.4529-4532
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• 2013

Background: Acute normovolemic hemodilution (ANH) has been widely used to prevent the massive blood loss during hepatic carcinoma. The influences of ANH on coagulation function are still controversy, especially in elderly patients. The study observed ANH effects on coagulation function and fibrinolysis in elderly patients undergoing the disease. Materials and Methods: Thirty elderly patients (aged 60-70 yr) with liver cancer (ASA I or II) taken hepatic carcinectomy from February 2007 to February 2008 were randomly divided into ANH group (n=15) and control group (n=15). After tracheal intubation, patients in ANH group and control group were infused with 6% hydroxyethyl starch (130/0.4) and Ringer's solution, respectively. Blood samples were drawn from patients in both groups at five different time points: before anesthesia induction (T1), 30 min after ANH (T2), 1 h after start of operation (T3), immediately after operation (T4), and 24 h after operation (T5). Then coagulation function, soluble fibrin monomer complex (SFMC), prothrombin fragment (F1+2), and platelet membrane glycoprotein (CD62P and activated GP IIb/GP IIIa) were measured. Results: The perioperative blood loss and allogeneic blood transfusion were recorded during the surgery. The perioperative blood loss was not significantly different between two groups (p>0.05), but the volume of allogeneic blood transfusion in ANH group was significantly less than in control group ($350.0{\pm}70.7$) mL vs. ($457.0{\pm}181.3$) mL (p<0.01). Compared with the data of T1, the prothrombin time (PT) and activated partial thromboplastin time (APTT) measured after T3 were significantly longer (p<0.05) in both groups, but within normal range. There were no significant changes of thrombin time (TT) and D-dimer between two groups at different time points (p>0.05). SFMC and F1+2 increased in both groups, but were not statistically significant. PAC-1-positive cells and CD62P expressions in patients of ANH group were significantly lower than those at T1 (p<0.05) and T2-T5 (p>0.05). Conclusions: ANH has no obvious impact on fibrinolysis and coagulation function in elderly patients undergoing resection of liver cancer. The study suggested that ANH is safe to use in elderly patients and it could reduce allogeneic blood transfusion.

• IMMUNE NETWORK
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• 제7권2호
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• pp.66-74
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• 2007

Background: The genus Flavivirus consists of many emerging arboviruses, including Dengue virus (DV), Japanese encephalitis virus (JEV) and West Nile virus (WNV). Effective preventive vaccines remain elusive for these diseases. Mice are being increasingly used as the animal model for vaccine studies. However, the pathogenic mechanisms of these viruses are not clearly understood. Here, we investigated the interaction of DV and JEV with murine bone marrow-derived dendritic cells (bmDC). Methods: ELISA and FACS analysis were employed to investigate cytokine production and phenotypic changes of DCs obtained from bone marrow following flavivirus infection. Results: We observed that these viruses altered the cytokine profile and phenotypic markers. Although both viruses belong to the same family, JEV-infected bmDC produced anti-inflammatory cytokine (IL-10) along with pro-inflammatory cytokines, whereas DV infection induced production of large amounts of pro-inflammatory cytokines (IL-6 and TNF-${\alpha}$) and no IL-10 from murine bmDCs. Both flaviviruses also up-regulated the expression of co-stimulatory molecules such as CD40, CD80 and CD86. JEV infection led to down-regulation of MHC II expression on infected bmDCs. We also found that cytokine production induced by JEV and DV is MyD88-dependent. This dependence was complete for DV, as cytokine production was completely abolished in the absence of MyD88. With regard to JEV, the absence of MyD88 led to a partial reduction in cytokine levels. Conclusion: Here, we demonstrate that MyD88 plays an important role in the pathogenesis of flaviviruses. Our study provides insight into the pathogenesis of JEV and DV in the murine model.

• Nutrition Research and Practice
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• 제10권3호
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• pp.313-320
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• 2016

BACKGROUND/OBJECTIVES: This study was conducted to compare the overall changes in dietary intake and metabolic syndrome risk parameters in Vietnamese marriage-based female immigrants over time. SUBJECTS/METHODS: The subjects of this study were 581 Vietnamese marriage-based female immigrants, who were recruited from local clinical centers in Korea. Baseline data were collected from 2006-2011 and the follow-up data were collected from 2012-2014. Dietary food intake was assessed by a 1-day 24-hour recall method. RESULTS: Compared to the baseline, the mean body weight, body mass index, waist circumference, high density lipoprotein (HDL)-cholesterol, systolic blood pressure and diastolic blood pressure increased while the fasting blood sugar, triglycerides and low density lipoprotein-cholesterol decreased at follow-up. The total consumption of foods such as vegetables/fruits/seaweeds/mushrooms, oil and fat, and eggs decreased during the follow-up period, whereas the consumption of sugars, beverages and meats increased. Partial correlation between the rate of change [(Follow-up - Baseline) / Baseline ${\times}100$] in metabolic syndrome risk parameters and food intake after controlling for confounding factors showed that the waist circumference was positively correlated with either the total plant food intake (r = 0.1042, P = 0.0129) or the total food intake (r = 0.0880, P = 0.0359). The plasma levels of total cholesterol (r = -0.1918, P = 0.0289) and HDL-cholesterol (r = -0.1424, P = 0.0007) were negatively correlated with the percentage of total intake from plant food, and HDL-cholesterol levels were positively correlated with the intake of total animal food (r = 0.0980, P = 0.0217). The serum C-reactive protein levels were positively correlated with the total intake of animal food (r = 0.2374, P < 0.0001) or the percentage of total intake from animal food (r = 0.1346, P = 0.0016). CONCLUSIONS: These results suggest that the change rate of dietary intake such as total plant food or animal food is associated with the change rates of metabolic syndrome risk parameters.

• 대한기계학회논문집B
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• 제35권12호
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• pp.1285-1292
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• 2011

본 연구에서는 전자식 팽창밸브를 적용한 반도체 공정용 칠러에 관한 실험적 연구를 통해 시스템 특성을 파악하였다. 또한 온도 변화에 따른 신속한 대응을 할 수 있도록 온도상승 및 하강실험, 부하변화에 따른 온도영역별 제어정밀도 실험을 함으로써 각 제어 방식에 따른 운전 특성을 파악하였다. 온도상승 시 소비전력은 8.9 kW로 측정되었으며 CH1이 37.5분, CH2가 39.5분이 소요되었으며, 온도하강에는 총 26.5분이 소요되었다. 부분부하가 적용되는 경우 전부하가 적용되는 경우에 비해 제어정밀도의 변화폭이 큰 것으로 나타났으며 스텝모터 구동방식을 적용한 CH2의 제어정밀도가 상대적으로 우수한 것으로 나타났다. 냉각수를 이용한 냉각사이클 영역에서 소비전력은 1.8 kW로 냉동사이클을 적용한 방식에 비해 절반가량으로 감소된 것으로 나타났다. 본 연구는 실험결과를 바탕으로 반도체 공정용 칠러의 최적제어방안을 제시하였다.

• Korean Chemical Engineering Research
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• 제47권3호
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• pp.292-302
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• 2009

페놀 습식산화에 미치는 반응온도($150{\sim}250^{\circ}C$), 산소분압(25.8~75.0 bar) 및 초기 pH(1.0~12.0)의 영향을 10 g/l의 페놀 초기농도를 사용하여 조사하였다. 습식산화속도는 화학적 산소요구량 COD를 이용하여 산출하였으며 반응 중간 생성물들을 고성능액체크로마토그래피를 사용하여 측정하였다. 습식산화 중 페놀 분해속도는 페놀에 대하여 1차 반응차수를 나타냈으며, COD 변화는 lumped 모델로 잘 묘사할 수 있었다. 금속이온($Cu^{2+}$, $Fe^{2+}$, $Zn^{2+}$, $Co^{2+}$, $Ce^{3+}$) 균일촉매의 습식산화 중 페놀 분해속도 및 COD 제거속도에 미치는 영향도 조사하였다. 페놀 분해속도 및 COD 제거속도는 $CuSO_4$를 사용한 촉매습식산화에서 가장 크게 나타났으며 촉매농도를 증가시킴에 따라 증가하였다. 습식산화 중 생성되는 개미산의 분해속도는 반응온도 및 $CuSO_4$ 농도를 증가시킴에 따라 증가하였다. 난분해성 생성물 초산의 최종농도는 반응온도를 증가시킴에 따라 증가하였으나 $CuSO_4$ 농도를 증가시킴에 따라 감소하였다.

• 한국산학기술학회논문지
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• 제17권8호
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• pp.544-559
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• 2016

본 연구는 직종별 대기업 종사자 635명을 대상으로 상사의 변혁적 리더십과 조직몰입의 관계에서 지식경영활동의 매개효과와 상사의 변혁적 리더십이 지식경영활동과 조직몰입에 대한 관계성 분석을 직종별 비교 분석하였다. 본 연구의 결과를 요약하면 다음과 같다. 상사의 변혁적 리더십이 지식경영활동에 모두 유의한 영향을 미치는 것으로 나타났으며, 상사의 변혁적 리더십이 조직몰입에 모두 유의한 영향을 미치는 것으로 나타났다. 또한, 지식경영활동도 조직몰입에 유의한 영향을 미치는 것으로 나타났다. 상사의 변혁적 리더십이 조직몰입 간에 지식경영활동의 매개역할에 관해서 부분매개효과를 나타내는 것으로 분석되었으며, 마지막으로, 각 집단별로 분석한 결과에 대해서는 상사의 변혁적 리더십이 지식경영활동에 미치는 영향에서는 서비스업이 가장 큰 것으로 나타났으며, 지식경영활동이 조직몰입에 미치는 영향에서도 서비스업이 가장 큰 것으로 나타났다. 또한 상사의 변혁적 리더십이 조직몰입에 미치는 영향에서는 IT업이 가장 큰 것으로 나타났다. 본 연구에서 변혁적 리더십은 조직유효성을 증진시키는 선행요인으로 중요하게 인지되었으며, 이러한 결과는 변혁적 리더십이란 목표달성에 그치지 않고 변화와 혁신을 추구함과 동시에 조직구성원들이 지니고 있는 잠재적 역량과 강점을 개발하고 자신감과 열정을 증대시킬 뿐만 아니라, 긍정적 강점을 자극하여 기대했던 것보다 높은 성과를 달성하도록 하는 것을 의미한다.

• 한국산학기술학회논문지
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• 제12권10호
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• pp.4322-4327
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• 2011

본 연구는 여중생들에게 봉사체험활동의 일환으로 정기적으로 실시한 노인봉사활동이 그들의 진로발달에 어떠한 영향을 미쳤는지에 대해 분석하였다. 연구대상은 경기도에 소재한 Y여자중학교에서 인근 노인복지시설에 정기적으로 봉사활동을 실시한 2학년생 30명이다. 연구도구 및 내용은 진로태도성숙도검사지(CAMI)와 진로결정검사지 (CDS)를 사용하여, 구체적으로 진로태도성숙도의 5가지의 하위요인(결정성, 준비성, 독립성, 목적성, 확신성)과 진로결정 수준의 변화에 대해 살펴보았다. 연구결과는 첫째, 노인봉사활동이 여중생의 진로태도성숙도의 향상에 부분적인 도움을 주는 것으로 나타났다. 둘째, 노인봉사활동이 여중생의 진로결정수준을 향상시키는데 도움을 주는 것으로 나타났다. 셋째, 가족단위로 함께 참여했을 경우가 진로태도성숙도와 진로결정수준을 높이는데 보다 효과적인 것으로 나타났다. 본 연구결과로 볼 때, 노인봉사활동을 가족단위로 참여하는 것은 여중생의 진로발달에 도움을 주므로 진로 교육 프로그램을 계획할 때, 관련내용을 포함시키는 것이 효과적일 것으로 사료된다.

• 한국산학기술학회논문지
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• 제21권9호
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• pp.32-38
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• 2020

화차 제동은 공기 제동관의 압력변화를 이용해 제동 체결과 완해를 반복적으로 작동하여 수행한다. 화차 공기 제동 완해 불량은 기관사의 제동완해 취급 후에 제동 제어밸브의 오작동으로 인해 부분적인 제동체결상태를 의미한다. 이 현상은 화차 주행 동안 차륜 찰상과 열손상을 발생시킴으로서, 차륜파손 또는 열차 탈선사고를 일으킨다. 따라서 화차의 운행 지연 및 사고방지를 위해서는 공기제동 완해불량을 방지하는 체계적인 연구가 중요하다. 이를 해결하기 위하여 본 연구에서는 철도운영기관의 제작과 기능요구사항을 고려하여 완해불량 방지밸브를 개발하였다. 또한 본 밸브의 내구성 시험은 화차제동성능 시뮬레이터 성능시험기를 이용하였으며, 이의 작동성능은 반복적인 제동과 완해불량 조건하에 공압이력으로부터 평가하였다. 본 밸브의 보증수명은 화차 주행동안 제동횟수를 고려하여 무고장 시험기법에 준하여 12개 시제품에 대하여 총 16만회 성능시험을 수행하였다. 내구성 시험동안 본 밸브의 공압 입력 시간과 출력시간 및 출력속도의 차이는 거의 일정하였다. 본 밸브의 보증수명은 신뢰수준 95%에서 59,860회이며, 화차 대차에 본 밸브를 설치할 경우에 요구조건인 4년간 고장없이 운용될 수 있음을 의미한다.

• Journal of Biosystems Engineering
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• 제41권3호
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• pp.273-280
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• 2016

Purpose: This experiment was conducted to detect water stress in terms of the moisture content of cucumber seedlings under water stress condition using a hyperspectral image acquisition system, linear regression analysis, and partial least square regression (PLSR) to achieve a non-destructive measurement procedure. Methods: Changes in the reflectance spectrum of cucumber seedlings under water stress were measured using hyperspectral imaging techniques. A model for estimating moisture content of cucumber seedlings was constructed through a linear regression analysis that used the moisture content of cucumber seedlings and a normalized difference vegetation index (NDVI). A model using PLSR that used the moisture content of cucumber seedlings and reflectance spectrum was also created. Results: In the early stages of water stress, cucumber seedlings recovered completely when sub-irrigation was applied. However, the seedlings suffering from initial wilting did not recover when more than 42 h passed without irrigation. The reflectance spectrum of seedlings under water stress decreased gradually, but increased when irrigation was provided, except for the seedlings that had permanently wilted. From the results of the linear regression analysis using the NDVI, the model excluding wilted seedlings with less than 20% (n=97) moisture content showed a precision ($R^2$ and $R^2_{\alpha}$) of 0.573 and 0.568, respectively, and accuracy (RE) of 4.138% and 4.138%, which was higher than that for models including all seedlings (n=100). For PLS regression analysis using the reflectance spectrum, both models were found to have strong precision ($R^2$) with a rating of 0.822, but accuracy (RMSE and RE) was higher in the model excluding wilted seedlings as 5.544% and 13.65% respectively. Conclusions: The estimation model of the moisture content of cucumber seedlings showed better results in the PLSR analysis using reflectance spectrum than the linear regression analysis using NDVI.