• 대한수혈학회지
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• 제29권3호
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• pp.240-252
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• 2018

점탄성 응고 검사법은 전혈 검사법으로 혈장성분뿐 아니라 응고 과정의 세포 기반 측면까지 동시에 볼 수 있는 방법이다. 프로트롬빈시간이나 활성화부분트롬보플라스틴시간과 같은 기존의 응고 검사법과 달리 이 검사는 현장 현시 검사로 즉시 시행할 수 있다. 점탄성 응고 검사법은 사망률 등의 예후 예측 인자이고, 응고 장애를 좀 더 예민하게 감지하여 결과적으로 출혈을 줄여주는 효과를 줄 수 있다. 점탄성 응고 검사 결과를 이용한 수혈 전략이 수혈 요구량을 줄여주었다고 보고되기도 하였다. 아직 이 방법의 정확성과 신뢰도에 대한 우려가 있기도 하지만, ROTEM 등의 점탄성 응고 검사법은 환자혈액관리에 응용하는 것은 유용할 것이다.

• Environmental Engineering Research
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• 제15권2호
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• pp.63-70
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• 2010

In this study, the response surface method and experimental design were applied as an alternative to conventional methods for the optimization of coagulation tests. A central composite design, with 4 axial points, 4 factorial points and 5 replicates at the center point were used to build a model for predicting and optimizing the coagulation process. Mathematical model equations were derived by computer simulation programming with a least squares method using the Minitab 15 software. In these equations, the removal efficiencies of turbidity and total organic carbon (TOC) were expressed as second-order functions of two factors, such as alum dose and coagulation pH. Statistical checks (ANOVA table, $R^2$ and $R^2_{adj}$ value, model lack of fit test, and p value) indicated that the model was adequate for representing the experimental data. The p values showed that the quadratic effects of alum dose and coagulation pH were highly significant. In other words, these two factors had an important impact on the turbidity and TOC of treated water. To gain a better understanding of the two variables for optimal coagulation performance, the model was presented as both 3-D response surface and 2-D contour graphs. As a compromise for the simultaneously removal of maximum amounts of 92.5% turbidity and 39.5% TOC, the optimum conditions were found with 44 mg/L alum at pH 7.6. The predicted response from the model showed close agreement with the experimental data ($R^2$ values of 90.63% and 91.43% for turbidity removal and TOC removal, respectively), which demonstrates the effectiveness of this approach in achieving good predictions, while minimizing the number of experiments required.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제13권1호
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• pp.23-29
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• 2010

목 적: 본 연구에서는 소아의 내시경 시술 전 출혈의 위험성을 예측하는 검사로 혈소판과 혈액 응고 검사의 임상적 의의를 평가하고자 하였다. 방 법: 2004년 3월부터 2009년 12월까지 분당서울대학교병원 소아청소년과 외래 및 입원 환자 중에서 위장관 내시경 검사를 시행 받은 소아청소년 환자의 의무기록과 혈소판 수치 및 혈액 응고 검사 결과들을 후향적으로 분석하였다. 결 과: 총 1,476건의 검사 결과, 혈소판 수치가 정상보다 낮은 경우는 1명이었고, PT INR만이 비정상으로 연장된 경우가 25건(1.7%)이었고, aPTT만 연장된 경우가 132건(9%)이었고, 둘 다 연장된 경우가 5건(0.3%)이었다. aPTT 결과가 비정상이었던 경우에 혈액 응고 인자 검사를 시행한 경우가 14건이었고, 이 중 혈액 응고인자 XII 결핍증으로 진단된 경우가 7명, 폰 빌레블란드 병으로 진단된 경우가 1명, 폰 빌레블란드 병과 혈액 응고 인자 XII 결핍증이 동시에 나타난 경우가 1명, 경증의 A형 혈우병이 의심된 경우가 1명이었으며, 나머지 4명은 정상이었다. 혈액 응고 질환으로 진단된 환자를 포함하여 내시경 시술을 받은 모든 소아 환자에서 의미 있는 출혈 합병증이 나타난 경우는 없었다. 결 론: 소아 내시경 사전 검사로 시행하는 혈액 응고검사에서 일부 이상 소견이 확인되더라도 실제 혈액 응고 질환으로 진단되는 경우는 드물고, 혈액 응고 질환으로 진단된 환자에서조차 내시경 시술에 의한 출혈 합병증이 나타나지 않았다. 따라서 내시경 시술 전에 모든 환자를 대상으로 혈액 응고 검사 및 혈소판 검사를 반드시 시행할 필요는 없을 것으로 여겨지며, 출혈 경향을 나타내는 과거력과 가족력이 있는 소아와 이전에 혈액 응고 검사를 한 번도 시행 받지 않았던 영유아 환자에서 내시경 시술 전에 혈액 응고 검사를 시행하는 것이 바람직할 것이다.

• 상하수도학회지
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• 제26권3호
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• pp.443-451
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• 2012

Wastewater treatment plants need to reduce phosphorus in order to meet increasingly stringent regulations on phosphorus. This study evaluated the feasibility of dolomite as a coagulation aid to enhance phosphorus removal from secondary treated wastewater by chemical coagulation. Standard jar tests were conducted to evaluate the effect of dolomite addition on a coagulation process for phosphorus removal and to determine the optimum doses of coagulants and dolomite. Coagulants used with dolomite yielded a significant improvement in phosphorus removal and reduced total phosphorus concentrations below 0.02 mg/L in wastewater effluent. Dolomite has played an important role in enhancing phosphate adsorption and increasing pH, as a coagulation aid. The maximum removal efficiency of phosphorus in this study was yielded at 25 mg/l of dolomite and 20 mg Al/L of PAC dose. However, considering economic aspects, the optimum doses of dolomite and PAC were 10 mg/L and 15mg Al/L, respectively. Consequently, dolomite, a coagulation aid, can be used in coagulation processes to enhance the removal of phosphorus.

• 대한관절경학회지
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• 제16권2호
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• pp.121-127
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• 2012

목적: 관절경 수술을 시행 받은 환자의 항응고 요법이 응고능에 미치는 영향과 대표적 항응고 약물 사이에 차이가 있는지 알아보기 위하여 항응고 약물 중 두 종류를 선택하여 사용한 환자들의 혈액 응고 검사를 수술 전후에 시행하여 수술 전 후 및 두 약물 간에 차이가 나타나는지에 대해 알아보았다. 대상 및 방법: 관절경 수술을 시행한 47예의 슬관절 혹은 고관절 환자를 대상으로 하였으며 환자군을 무작위로 enoxaparin과 rivaroxaban을 사용한 두 그룹으로 나누어 수술 전 및 수술 후 5일째 응고 검사를 시행하여 수술 전후 및 두 약물간의 결과를 비교하였다. 결과: 수술 전 시행한 응고 검사에서는 두 그룹간의 유의한 차이가 없었으나(P>0.05) 수술 후 5일째 시행한 응고 검사에서는 prothrombin time-international normalized ratio (PT-INR), activated partial thromboplastin time (aPTT)에서 증가 소견을 보였고 특히 rivaroxaban 환자군의 수치가 증가한 것으로 나타났다(P<0.05). 결론: 관절경 수술의 약물을 통한 항응고 요법은 혈액 검사를 통한 결과에서 출혈 경향 면에서 안전한 범위에서 수술전과 비교하여 통계적으로 유의한 차이를 보였으나 rivaroxaban을 사용한 환자 군에서 응고능의 정상 범위를 넘어서는 환자가 있어 rivaroxaban의 사용에 주의를 요할 것으로 생각된다.

• 한국분무공학회지
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• 제11권2호
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• pp.98-104
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• 2006

A charged droplet scrubber was introduced to remove visible smokes generated in many industrial facilities. Lab-scale and field tests were conducted in this study. The system consists of a corona discharger to effectively charge the fine particles, fellowed by an electrostatic chamber to promote coagulation between charged fine particles and oppositely charged droplets and a demister to remove resultant particles. Overall collection efficiency, 98.4% was obtained from a lab-scale test, when a high voltage was applied to an ionizer and a charged droplet scrubber. Field tests also show the high collection efficiencies, 93.5% with one stage and 99.4% with two stage system. This system can be used to increase the collection efficiency of the conventional air pollution control devices to satisfy the national emission standard.

• 한국임상수의학회지
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• 제34권2호
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• pp.65-69
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• 2017

Thromboembolic complications are increasing in veterinary medicine. Thromboelastography (TEG) is a more comprehensive method for assessing the clotting process than standard plasma-based coagulation tests. This study compared the ability of TEG and standard coagulation tests to analyze the overall hemostatic state of dogs. The study involved 40 dogs with underlying diseases that predispose to hypercoagulability, including neoplasia, hyperadrenocorticism, immune-mediated diseases, gastrointestinal diseases, and protein-losing nephropathies and enteropathies, and 20 healthy dogs. Their overall hemostatic functional state was evaluated by TEG and routine coagulation assays, including activated partial thromboplastin time, prothrombin time, platelet count, and D-dimer concentration. TEG analysis showed significant differences in clot formation time, ${\alpha}$ angle, and maximum amplitude (MA) between diseased and control dogs (P < 0.001 each). Increased MA was the most frequent abnormality on TEG and was indicative of hypercoagulability. TEG was useful in detecting hemostatic dysfunction in dogs with diseases associated with hypercoagulability. Dogs with TEG tracings indicative of hypercoagulability are likely to be in procoagulant states. Future prospective studies are needed to evaluate whether TEG tracings indicative of hypercoagulability are predictive of thrombosis in dogs.

• 한국환경과학회지
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• 제22권10호
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• pp.1353-1361
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• 2013

The objectives of this paper are the characterization of the pretreatment of wastewater by microfiltration (MF) membranes for river maintenance and water recycling. This is done by investigation of the proper coagulation conditions, such as the types and doses of coagulants, mixing conditions (velocity gradients and mixing periods), pH, etc., using jar tests. The effluent water from a pore control fiber (PCF) filter located after the secondary clarifier at Kang-byeon Sewage Treatment Plant (K-STP) was used in these experiments. Two established coagulants, aluminum sulfate (Alum) and poly aluminum chloride (PAC), which are commonly used in sewage treatment plants to treat drinking water, were used in this research. The results indicate that the optimal coagulation velocity gradients (G) and agitation period (T) for both Alum and PAC were 200-250 $s^{-1}$ and 5 min respectively, but the coagulation efficiencies for both Alum and PAC were lower at low values of G and T. For a 60 min filtration period on the MF, the flux efficiencies ($J/J_0$ (%)) at the K-STP effluent that were coagulated by PAC and Alum were 92.9 % and 79.9 %, respectively, under the same coagulation conditions. It is concluded that an enhanced membrane process is possible by effective filtration of effluent at the K-STP using the coagulation-membrane separation process.

• Environmental Engineering Research
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• 제20권3호
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• pp.223-229
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• 2015

The application of coagulation for feed water pretreatment prior to microfiltration (MF) process has been widely adopted to alleviate fouling due to particles and organic matters in feed water. However, the efficiency of coagulation pretreatment for MF is sensitive to its operation conditions such as pH and coagulant dose. Moreover, the optimum coagulation condition for MF process is different from that for rapid sand filtration in conventional drinking water treatment. In this study, the use of response surface methodology (RSM) was attempted to determine coagulation conditions optimized for pretreatment of MF. The center-united experimental design was used to quantify the effects of coagulant dose and pH on the control of fouling control as well as the removal organic matters. A MF membrane (SDI Samsung, Korea) made of polyvinylidene fluoride (PVDF) was used for the filtration experiments. Poly aluminum chloride (PAC) was used as the coagulant and a series of jar tests were conducted under various conditions. The flux was $90L/m^2-h$ and the fouling rate were calculated in each condition. As a result of this study, an empirical model was derived to explore the optimized conditions for coagulant dose and pH for minimization of the fouling rate. This model also allowed the prediction of the efficiency of the coagulation efficiency. The experimental results were in good agreement with the predictions, suggesting that RSM has potential as a practical method for modeling the coagulation pretreatment for MF.

• 한국동물위생학회지
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• 제45권1호
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• pp.55-61
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• 2022

In veterinary medicine, a variety of disease are known to cause coagulation abnormalities. Identification of these coagulation abnormalities have been relied on traditional coagulation assays(platelet concentration, aPTT, PT, D-dimer, fibrinogen) which take only a small part of the coagulation pathways rather than global hemostatic capacity. Among of the hypercoagulable diseases, cardiovascular disease, such as mitral valvular disease, was not regarded as the cause of the hypercoagulability. The value of a thromboelastography (TEG) as an early predictor of coagulopathy, especially hypercoagulability, has been founded. It was associated with decreased R and K values, and increased MA and α angle. The objective of this study was to compare thromboelastography results and those of traditional coagulation tests between twenty adult dogs with mitral insufficiency (MVI group) and eleven adult healthy dogs (Healthy group). As a results, MA values in the patients with mitral insufficiency (68.8±7.8 mm) were significantly higher than the normal patients (60.4±4.8 mm) (P value<0.05). Although a little report has been reported in veterinary medicine, platelet activation seems to be related with hypercoagulability in MVI patients in human medicine. The result of this report can support this pathophysiology in veterinary medicine. In addition to traditional coagulation assay, global assessment of coagulopathy using TEG, especially ability to detect hypercoagulability, may be useful for customized treatment in MVI patients. To achieve this, further study is needed to define pathophysiology and effect of medication.