• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVII)
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• pp.266-269
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• 2005

반응조의 유입수 CODcr농도를 $75000{\sim}95000mg/L$로 운전하였을 경우 유출수 CODcr농도는 $14000{\sim}19000mg/L$로서, 제거율은 $75{\sim}85%$로 나타났다. 고온소화$(45{\pm}2^{\circ}C)$로 운전한 결과 유입수 pH는 $4.2{\sim}4.5,$ 유출수의 pH는 $6.8{\sim}7.2$를 유지하였다. TS(총고형물질)와 VS(휘발성고형물질)의 유입수를 단계적으로 각각 $2.94{\sim}5.09%$와 $2.98{\sim}5.01%$로 유지할 경우, 유출수는 단계적으로 각각 $0.65{\sim}1.1%$와 $0.6{\sim}0.8%$였다. 유출수의 TS, VS의 제거율은 각각 78, 85%이었다. $CH_4$발생량은 0.28 $m^3-CH_4/kg-VS$이었다.

• Asian Pacific Journal of Cancer Prevention
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• 제16권1호
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• pp.271-274
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• 2015

Background: To explore vascular endothelial growth factor C (VEGF-C) and VEGF-D expression and its correlation with lymph node metastasis in esophageal squamous cell cancer (ESCC) tissue. Materials and Methods: Immunohistochemical methods were applied to detect the levels of VEGF-C and VEGF-D expression in 64 surgicall removal ESCC tissues, tissues adjacent to cancer and normal tissues, and the relationship between VEGF-C and VEGF-D expression and lymph node metastasis was analyzed. Results: Both VEGF-C and VEGF-D were expressed by varying degrees in esophageal cancer tissue, the tissue adjacent to cancer and normal tissue, and the positive expression rate went down successively. The positive expression rates of VEGF-C (59.4%) and VEGF-D (43.8%) in esophageal cancer tissue were significantly higher than in the tissue adjacent to cancer (34.4%, 15.6%) and normal tissue (20.3%, 12.5%), respectively, in which significant differences were manifested (p<0.01). Positive expression rates of VEGF-C and VEGF-D in esophageal cancers with lymph node metastasis were markedly higher than without such metastasis (p<0.01), while those in the tissue with TNM staging I~II were markedly lower than that with TNM staging III~IV (p<0.01). Conclusions: Both VEGF-C and VEGF-D are highly expressed in ESCC tissue, which may be related to the lymph node metastasis of cancer cells. Hence, VEGF-C and VEGF-D can be clinically considered as important reference indexes of lymph node metastasis in esophageal cancer.

• 한국축산시설환경학회지
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• 제21권3호
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• pp.83-92
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• 2015

An attempt to produce more pigs in limited spaces inevitably generalized concentrated feeding operation (CFO). As concentrated pig production practice expanded, concerns on environmental issues grow concurrently. Since odor is the concerned most among those, we attempted to develop means to tackle odor emission from livestock operations. Previously, we excavated few microorganisms from pig manure and, one of them, Bacillus licheniformis was particularly useful to handle odor problem. In this study, we conducted our investigation to further characterize Bacillus licheniformis. Strain identification was conducted using Vitek 2 compact, and the optimal temperature and pH conditions to growth B. licheniformis were searched for by analyzing turbidity on O.D 600 nm. Results of this study can be summarized as these, (1) it was re-verified that the bacterial strain that purified from pig manure was, in fact, Bacillus licheniformis, (2) the bacterial growth was highest when the temperature was kept at $30^{\circ}C$, also (3) growth rate was dependent on media pH as it was high at neutral (6, 7 and 8) but dropped when it was diverged from neutral (4, 5, 9 and 10), and (4) regarding ammonia removal efficiency, B. licheniformis recorded 64% effectiveness after 48 h incubation and reached its highest (80%) at 72 h.

• 생명과학회지
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• 제16권6호
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• pp.877-883
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• 2006

발효산업에 많이 사용되는 A. pullulans를 사용하여 독성 중금속인 납에 대한 제거량을 살펴보았다. 용액 중의 중금속을 제거할 때 A. pullulans가 다른 중금속에 비해 납에 대한 선택성이 우수하였으며 $40^{\circ}C$에서 최대 흡착량을 나타내었으며 또한 최적 pH가 9일 경우에 흡착량이 증가하였다. 초기납의 농도가 96 mg/l 인 경우에 단위 미생물당 흡착량이 120mg/g로 짧은 시간내에 많은 양의 납을 제거함을 알 수 있었다. 그리고 약 200 mg Pb/g cell dry weight 정도가 최대 납 흡착량인 것으로 나타났다. 그리고 미생물의 보존기간에 따라 세포외 고분자물질의 분비가 증가하여 납 흡착량을 증가시켰으며, Freundlich 모델에 잘 적용되었다. 그리고 살아있는 상태가 사멸된 상태에서 평형흡착량은 약 2배 정도 흡착능이 우수함을 알 수 있었으며, 그에 따라서 초기 흡착속도도 살아있는 상태가 사멸된 상태보다 훨씬 빠른 것을 알 수 있었다.

• KSBB Journal
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• 제22권4호
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• pp.244-248
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• 2007

고농도 페놀폐수 전처리 습식산화공정의 반응온도, 초기 pH 및 균일촉매 ($CuSO_4$) 등이 후처리 호기성 생물학적 공정에 미치는 영향을 조사하였다. 습식산화에서의 높은 반응온도와 산성 초기조건이 후처리 생물학적 산화공정에서 높은 산화속도와 최종 COD 제거율을 유발하였다. 습식산화에서 균일촉매를 사용하면 전처리 습식산화반응은 낮은 반응온도에서도 높은 COD 제거속도를 보였으나, 후처리 생물학적 산화공정에서는 낮은 최종 COD 제거율을 나타내었다.

• 태양에너지
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• 제18권3호
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• pp.197-203
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• 1998

A 5 ton/day pilot scale two-phase anaerobic digester was constructed and tasted to treat Korean food wastes in Anyang city. The process was developed based on 3 years of lab-scale experimental results on am optimim treatment method for the recovery of biogas and humus. Problems related to food waste are ever Increasing quantity among municipal solid wastes(MSW) and high moisture and salt contents. Thus our food waste produces large amounts of leachate and bed odor in landfill sites which are being exhausted. The easily degradable presorted food waste was efficiently treated in the two-phase anaerobic digestion process. The waste contained in plastic bags was shredded and then screened for the removal of inert material such as fabrics and plastics, and subsequently put into the two-stage reactors. Heavy and light inerts such as bones, shells, spoons and plastic pieces were again removed by gravity differences. The residual organic component was effectively hydrolyzed and acidified in the first reactor with 5 days space time at pH of about 6.5. The second, methanization reactor part of which is filled with anaerobic fillters, converted the acids into methane with pH between 7.4 to 7.8. The space time for the second reactor was 15 days. The effluent from the second reactor was recycled to the first reactor to provide alkalinities. The process showed stable steady state operation with the maximum organic rate of 7.9 $kgVS/m^3day$ and the volatile solid reduction efficiency of about 70%. The total of 3.6 tons presorted MSW containing 2.9 tons of food organic was treated to produce about $230m^3$ of biogas with 70% of methane and 80kg humus. This process is extended to full scale treating 15 tons of food waste a day in Euiwang city and the produced biogas is utilized for the heating/cooling of adjacent buildings.

• 대한의용생체공학회:의공학회지
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• 제35권4호
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• pp.87-94
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• 2014

Recent technological advances have increased interest in personal health monitoring. Electrocardiogram(ECG) monitoring is a basic healthcare activity and can provide decisive information regarding cardiovascular system status. In this study, we developed a capacitive ECG measurement system that can be included within a cloth mattress pad. The device permits ECG data to be obtained during sleep by using capacitive electrodes. However, it is difficult to detect R-wave peaks automatically because signals obtained from the system can include a high level of noise from various sources. Because R-peak detection is important in ECG applications, we developed an algorithm that can reduce noise and improve detection accuracy under noisy conditions. Algorithm reliability was evaluated by determining its sensitivity(Se), positive predictivity(+P), and error rate(Er) by using data from the MIT-BIH Polysomnographic Database and from our capacitive ECG system. The results showed that Se = 99.75%, +P = 99.77%, and Er = 0.47% for MIT-BIH Polysomnographic Database while Se = 96.47%, +P = 99.32%, and Er = 4.34% for our capacitive ECG system. Based on those results, we conclude that our R-peak detection method is capable of providing useful ECG information, even under noisy signal conditions.

• Environmental Engineering Research
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• 제19권2호
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• pp.157-163
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• 2014

The adsorption of Cr(VI) from aqueous solutions to activated carbon fiber (ACF) was investigated using both batch and flow-through column experiments. The batch experiments (adsorbent dose, 10 g/L; initial Cr(VI) concentration, 5-500 mg/L) showed that the maximum adsorption capacity of Cr(VI) to ACF was determined to 20.54 mg/g. The adsorption of Cr(VI) to ACF was sensitive to solution pH, decreasing from 9.09 to 0.66 mg/g with increasing pH from 2.6 to 9.9; the adsorption capacity was the highest at the highly acidic solution pHs. Kinetic model analysis showed that the Elovich model was the most suitable for describing the kinetic data among three (pseudo-first-order, pseudo-second-order, and Elovich) models. From the nonlinear regression analysis, the Elovich model parameter values were determined to be ${\alpha}$ = 162.65 mg/g/h and ${\beta}$ = 2.10 g/mg. Equilibrium isotherm model analysis demonstrated that among three (Langmuir, Freundlich, Redlich-Peterson) models, both Freundlich and Redlich-Peterson models were suitable for describing the equilibrium data. In the model analysis, the Redlich-Peterson model fit was superimposed on the Freundlich fit. The Freundlich model parameter values were determined to be $K_F$ = 0.52 L/g and 1/n = 0.56. The flow-through column experiments showed that the adsorption capacities of ACF in the given experimental conditions (column length, 10 cm; inner diameter, 1.5 cm; flow rate, 0.5 and 1.0 mL/min; influent Cr(VI) concentration, 10 mg/L) were in the range of 2.35-4.20 mg/g. This study demonstrated that activated carbon fiber was effective for the removal of Cr(VI) from aqueous solutions.

• Journal of Korean Neurosurgical Society
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• 제30권7호
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• pp.855-860
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• 2001

Introduction : It has been reported that the survival of low-grade glioma patients depends upon the time of malignant transformation. The authors presents the clinical analysis of histologically proven trasformed gliomas. Materials and Method : A total 92 patients who were consecutively treated and histologically confirmed hemispheric low-grade gliomas between 1980 and 1998 were analyzed and followed. All cases meet the criteria of WHO glioma classification of grade II. Results : The mean follow-up period was 73 months. Twenty two among 92 cases(24%) were histologically proven to be transformed into malignant ones. The mean time to transformation was 56 months. The 5-year and 10-year survival rates of the transformed group were 66% and 30% respectively and significantly different from the survival rates of the non-transformed group(p=0.0018). Among clinical factors at presentation, the initial tumor volume had a tendency to be larger in the transformed group than that of the non-transformed group and became significant when it was divided into more than $30cm^3$ or not(p=0.02). Among therapeutic factors, the extent of removal had no influence on the rate of malignant transformation. But postoperative radiation therapy were more frequently given to the pre-transformed group than the non-transformed group and the frequency was significantly different(p=0.02). Conclusions : The authors had found that the initial tumor volume and radiation therapy could be clinical prognostic factors for the malignant transformation of low-grade gliomas.

• Journal of Veterinary Science
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• 제24권5호
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• pp.65.1-65.9
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• 2023

Background: Bone subtraction computed tomography angiography (BSCTA) is a useful alternative technique for improving visualization of vessels surrounded by skull bone. However, no studies have compared computed tomography angiography (CTA) and BSCTA for improving the visibility of canine cerebral blood vessels. Objectives: To evaluate the potential benefit of BSCTA for better delineation of brain arteries of the circle of Willis (CoW) in dogs by comparing BSCTA with non-subtraction computed tomography angiography (NSCTA). Methods: Brain CTA was performed for nine healthy beagle dogs using a bolus tracking method with saline flushing. A total dose of 600 mgI/kg of contrast agent with an iodine content of 370 mgI/mL was injected at a rate of 4 ml/s. Bone removal was achieved automatically by subtracting non-enhanced computed tomography (CT) data from contrast CT data. Five main intracranial arteries of the CoW were analyzed and graded on a scale of five for qualitative evaluation. Results: Scores of basilar artery, middle cerebral artery, and rostral cerebral artery in the BSCTA group were significantly higher than those in the NSCTA group (p = 0.001, p = 0.020, and p < 0.0001, respectively). Scores of rostral cerebellar artery (RcA) and caudal cerebral artery (CCA) did not differ significantly between the two groups. However, scores of RcA and CCA in the BSCTA group were higher than those in the NSCTA group. Conclusions: BSCTA improved visualization of intracranial arteries of the CoW with close contact to bone. Thus, it should be recommended as a routine scan method in dogs suspected of having brain vessel disease.