• 한국환경성돌연변이발암원학회지
• /
• 제21권1호
• /
• pp.1-8
• /
• 2001

We have synthesized $^{99m}$Tc-mercaptoacetyltriglycine (MAG3)-biocytin as a new imaging agent for hepatobiliary scintigraphy. The aim of this study was to evaluate the usefulness of $^{99m}$Tc-MAG3-biocytin scintigraphy in differentiating carbon tetrachloride ( $CCl_4$)-induced hepatotoxicity from $\alpha$-naphthylisothiocyanate (ANIT)-induced cholestasis in mice, which reflecting the differential diagnosis of neonatal jaundice caused by neonatal hepatitis from congenital biliary atresia in humans. Methods: Balb/c mice (female, 20 g, n=4-6) were pretreated with $CCl_4$(0.5 or $1.0m\ell$/kg) and ANIT ($150 or 300 m\ell$/kg) 18 h before scintigraphy. Biochemical and histopathological examinations showed a pattern of typical acute hepatitis (increase of transaminases and hepatocellular necnsis) in $CCl_4$-treated mice and cholestasis (increase of alkaline phosphatase and ${\gamma}$-glutamyltransferase, and biliary hyperplasia) in ANIT-treated mice, respectively, Mice were fasted at least 4 hr prior to the intravenous injection of $^{99m}$Tc-MAG3-biocytin (18.5 MBq/20$\mu\textrm{g}$) in 2% human serum albumin in saline. Scintigraphy was performed with a ${\gamma}$-camera equipped with a 1-mm diameter pin-hole collimator for 30 min and images were acquired every 15 s. We compared the values of physical parameters, such as peak liver/heart ratio ($${\gamma}$_{max}$) and peak ratio time ($t_{max}$) far $^{99m}$Tc-MAG3-biocytin scintigraphy. Results: Scintigraphic parameters of the $CCl_4$-pretreated (0.5 $m\ell$/kg) group showed a 81.9% decrease of r$_{max}$, and 42.2% decrease of $t_{max}$, whereas the ANIT-pretreated ( $150m\ell$/kg) group showed a 53% decrease of $r_{max}$, and 2.36-fold increase of $t_{max}$, (P<0.05). These results demonstrate that the decrease of $r_{max}$ and the shortening of $t_{max}$ are characteristic features for hepatotoxicity, in contrast to the increase of $t_{max}$ and decrease of $r_{max}$ for biliary hyperplasia. Conclusion: $^{99m}$Tc-MAG3-biocytin hepatobiliary scintigraphy can distinguish hepatitis from cholestasis in mice model and may be similarly useful in humans which differentiating the cause of neonatal jaundice in clinical study.cal study.cal study.cal study.

• 한국농공학회지
• /
• 제37권3_4호
• /
• pp.61-71
• /
• 1995

Natural ground is a composite consisted of the three phases of water, air and soil paircies. Among the three components, water as a material is weU understood but soil particles are not in foundation engineering. Especially, weathered granite soil generally shows a large volumetric expansion when they freeze. And, the stability and durability of the soil have shown decreased with repetitive freezing and thawing processes. These unique charcteristics may cause various construction and management problems if the soil is used as a construction material and foundation layers. This project was initiated to investigate the soil's physical and engineering characteristics resulting from freezing and freezing-thawing processes. Research results may be used as a basic data in solving various problems related to the soil's unique characteristics. The following conclusions were obtained: The degree of decomposition of weathered granite soil in Kangwon-do was very different between the West and East sides of the divide of the Dae-Kwan Ryung. Soil particles distributed wide from very coarse to fine particles. Consistency could be predicted with a function of P200 as LL=0.8 P200+20. Permeability ranged from 10-2 to 10-4cm/sec, moisture content from 15 to 20% and maximum dry density from 1.55 to 1.73 g /cmΥ$^3$ By compaction, soil particles easily crushed, D50 of soil particles decreased and specific surface significantly increased. Shear characteristics varied wide depending on the disturbance of soil. Strain characteristics influenced the soil's dynamic behviour. Elastic failure mode was observed if strain was less than 1O-4/s and plastic failure mode was observed if strain was more than 10-2/s. The elastic wave velocity in the soil rapidly increased if dry density became larger than 1.5 g /cm$^3$ and these values were Vp=250, Vg= 150, respectively. Frost heave ratio was the highest around 0 $^{\circ}C$ and the maximum frost heave pressure was observed when deformation ratio was less than 10% which was the stability state of soil freezing. The state had no relation with frost depth. Over freezing process was observed when drainage or suction freezing process was undergone. Drainage freezing process was observed if freezing velocity was high under confined pressure and suction frost process was occurred if the velocity was low under the same confined process.

• 한국산림과학회지
• /
• 제35권1호
• /
• pp.9-14
• /
• 1977

은수원사시나무(${\times}$P. albaglandulosa)조림지(造林地)에서 임분밀도(林分密度)가 693본(本)/ha의 6년생(年生), 625본(本) 또는 527본(本)/ha의 9년생(年生) 임분(林分)에 대하여 상대생장법(相對生長法)으로 현존량(現存量)과 생산성(生産性)을 추정(推定)하고 생산구조(生産構造)를 분석(分析)하였다. 1. 생산구조도(生産構造圖)의 광합성부(光合成部)는 층(層)을 형성(形成)하여 광선(光線)의 투입(透入)에 효과적(効果的)인 특징(特徵)을 나타내었다. 2. 지상부(地上部) 현존량(現存量)은 6년생(年生)이 18.11 ton/ha, 9년생(年生)이 38.8~47.3ton/ha 이며, 간재적(幹材積)은 6년생(年生)이 $31.3m^3/ha$, 9년생(年生)이 $68.8{\sim}83.9m^3/ha$이었다. 3. 년순생산량(年純生産量)은 6년생(年生)에서 4.8 ton/ha/yr, 9년생(年生)에서 10.0~11.7ton/ha/yr를 얻었고. 간재적(幹材積)의 순생산량(純生産量)은 $17.9{\sim}21.1m^3/ha/yr$로 나타났다. 4. 9년생(年生)의 표준지(標準地)에서 현존량(現存量) 및 순생산량(純生産量)에 차이(差異)가 생기는 이유(理由)는 토양(土壤)의 화학성분(化學成分)에 의하지 않고 물리적(物理的) 성질(性質)에 기인(起因)하는 것으로 사료(思料)되었다.

• 재활복지공학회논문지
• /
• 제11권3호
• /
• pp.261-270
• /
• 2017

바르지 못한 앉은 자세는 다양한 질병과 신체 변형을 유발한다. 하지만 오랜 시간동안 바른 앉은 자세를 유지하는 것은 쉬운 일이 아니다. 이러한 이유 때문에 그동안 자동으로 바른 앉은 자세를 유도하기 위한 다양한 시스템이 제안되어왔다. 이전에 제안되었던 앉은 자세 판별 및 바른 앉은 자세 유도 시스템은 영상 처리를 이용한 방법, 의자에 압력센서를 달아 측정하는 방법, IMU(Internal Measurement Unit)를 이용한 방법이 있었다. 이 중 IMU를 이용한 측정 방법은 하드웨어 구성이 간단하고, 공간, 광량 등의 환경적 제한이 적어 측정에 있어서 용이한 이점이 있었다. 본 논문에서는 하나의 IMU를 이용하여 적은 데이터로 효율적으로 앉은 자세를 분류하는 방법을 연구하였다. 특징추출 기법을 이용하여 데이터 분류에 기여도가 낮은 데이터를 제거하였으며, 머신러닝 기법을 이용하여 앉은 자세 분류에 적합한 센서 위치를 찾고, 여러 개의 머신러닝 모델 중 가장 분류 정확도가 높은 머신러닝 모델을 선정하였다. 특징추출 기법은 PCA(Principal Component Analysis)를 사용하였고, 머신러닝 모델은 SVM(Support Vector Machine), KNN(K Nearest Neighbor), K-means (K-means Algorithm) GMM (Gaussian Mixture Model), and HMM (Hidden Marcov Model)모델을 사용하였다. 연구결과 데이터 분류율이 높게나온 뒷목이 적합한 센서 위치가 되었으며, 센서 데이터 중 Yaw데이터는 분류 기여도가 가장 낮은 데이터임을 PCA 특징추출 기법을 이용하여 확인하고, 제거하여도 분류율에 영향이 매우 작음을 확인하였다. 적합 머신러닝 모델은 SVM, KNN 모델로 다른 모델에 비하여 분류율이 높게 나오는 것을 확인할 수 있었다.

• 한국환경과학회지
• /
• 제16권10호
• /
• pp.1203-1208
• /
• 2007

Feathers are produced in huge quantities as a waste product at commercial poultry processing plants. Since feathers are almost pure keratin protein, feather wastes represent an alternative to more expensive dietary ingredients for animal feedstuffs. Generally they become feather meal used as animal feed after undergoing physical and chemical treatments. These processes require significant energy and also cause environmental pollutions. Therefore, biodegradation of feather by microorganisms represents an alternative method to prevent environment contamination. The aim of this study was to investigate cultural conditions affecting keratinolytic protease production by Bacillus pumilus RS7. We also assessed the nutritive value of microbial and alkaline feather hydrolysates, The composition of optimal medium for the keratinolytic protease was fructose 0.05%, yeast extract 0.3%, NaCl 0.05%, K2HPO4 0.03%, KH2PO4 0.04% and MgCl2 6H2O 0.01%, respectively. The optimal temperature and initial pH was $30^{\circ}C$ and 9.0, respectively. The keratinolytic protease production under optimal condition reached a maximum after 18 h of cultivation. Total amino acid content of feather hydrolysates treated by NaOH and B. pumilius RS7 was $113.8\;{\mu}g/ml$ and $504.9\;{\mu}g/ml$, respectively. Essential amino acid content of feather hydrolysates treated by NaOH and B. pumilius RS7 was $47.2\;{\mu}g/ml$ and $334.0\;{\mu}g/ml$, respectively. Thus, feather hydrolysates have the potential for utilization as an ingredient in animal feed.

• 대한족부족관절학회지
• /
• 제7권2호
• /
• pp.208-217
• /
• 2003

Introduction: Soft-tissue impingement syndrome is now increasingly recognized as a significant cause of the chronic ankle pain. As a method to detect soft-tissue ankle impingement, a characteristic history and physical examination, routine MR imaging, and direct MR arthrography were used. The efficacy of routine MR imaging has been controversial for usefulness because of low sensitivity and specificity. Direct MR artrhography was recommaned for diagnosis because of the highest sensitivity, specificity and accuracy, but it requires an invasive procedure. The purpose of this study is to investigate the diagnostic accuracy of Fat suppressed, contrast enhanced, three-dimensional fast gradient recalled acquisition in the steady state with rediofrequency spoiling magnetic resonance imaging(CE 3D-FSPGR MRI) and to evaluate the clinical outcome of the arthroscopic treatment in assessing soft-tissue impingement associated with trauma of the ankle. Materials and Methods: We reviewed 38 patients who had arthroscopic evaluations and preoperative magnetic resonance imaging studies(3D-FSPGR MRI) for post-traumatic chronic ankle pain between January 2000 and August 2002. Among them, 24 patients had osteochondral lesion, lateral instability, loose body, malunion of lateral malleoli, and peroneal tendon dislocation. The patient group consisted of 23 men and 15 women with the average age of 34 years(16-81 years). The mean time interval from the initial trauma to the operation was 15.5 months(3 to 40 months), The mean follow-up duration of the assessment was 15.6months(12-48 months). MRI was simultaneously reviewed by two radiologists blinded to the clinical diagnosis. The sensitivity, specificity and accuracy of MRI was obtained from radiologic and arthroscopic finding. Arthroscopic debridement and additional operation for associated disease were performed. We used a standard protocol to evaluate patients before the operation and at follow-up which includes American Orthopedic Foot and Ankle Society Ankle-Hindfoot Score. Results: For the assessment of the synovitis and soft tissue impingement, fat suppressed CE 3D-FSPGR MR imaging had the sensitivity of 91.9%, the specificity of 84.4 and the accuracy of 87.5%. AOFAS Ankle-Hindfoot Score of preoperative state was 69.2, and the mean score of the last follow-up was 89.1. These were assessed as having 50% excellent(90-100) and 50% good(75-89). The presence of other associated disease didn't show the statistically significant difference(>0.05). Conclusion: Fat suppressed CE 3D-FSPGR MR imaging is useful method comparable to MR arthrography for diagnosis of synovitis or soft-tissue impingement, and arthroscopic debridement results in good clinical outcome.

• 대한치과보철학회지
• /
• 제38권4호
• /
• pp.446-460
• /
• 2000

All-ceramic restorations have had a more limited life expectancy than metal ceramic crowns be-cause of their lower strength. The relatively lower strength has limited the use of all-ceramic crowns to the areas where occlusal loads are lower Therefore many researches have been done to increase the strength of all-ceramic crowns. IPS Empress 2 is a new type of lithium disilicate glass-ceramic with enhanced physical characteristics which has been in use clinically since 1998. Previous researches reported that the flexural strength of all-ceramic material was greater than 300 MPa, and all-ceramic crowns can be used in staining or layering technique. The objective of this study was to investigate the influence of the thickness of IPS Empress 2 ceramic on fracture strength. Both staining technique and layering technique was investigated. Vita VMK was used as control. For all three groups, five specimens each of 0.8mm, 1.0mm, 1.4mm, 1.8mm, and 2.2mm thick-ness (a total of 75 specimens) were prepared. Control group : Vita VMK Porcelain specimens were prepared with dentine ceramic and liquid glazing was done. Group I : IPS Empress 2 were prepared with staining technique and stained twice and glazed once. Group II : IPS Empress 2 were prepared with layering technique and glazed after wash firing. The thickness and diameter of the specimen were measured and controlled after specimen preparation. Biaxial Flexure Test (ASTM Standard F394-78) was adopted as this test method produces results least affected by the edge condition of the specimens. Fracture strength was measured with Instron Universal Testing Machine. Conclusions are as follow : 1. The fracture strength was increase in order of control group, test group I, test group II. 2. Fracture strength of the group I (Empress 2 Staining) was 65.54 N in 0.8mm, 155.2 N in 1.0mm, 233.5 N in 1.4mm, 434.5 N in 1.8mm, and 600.1 N in 2.2mm. 3. Fracture strength of the group II (Empress 2 Layering) was 190.0 N in 0.8mm, 283.5 N in 1.0mm. 437.2 N in 1.4mm, 732.0 N in 1.8mm, and 1115.0 N in 2.2mm. 4. No statistical difference was found in flexural strengths according to thickness in a specified group(p>0.05).

• 수면정신생리
• /
• 제14권1호
• /
• pp.49-53
• /
• 2007

사립체근병증은 운동시 근력약화와 같은 경한 증상에서 부터 중추신경계 질환으로 조기 사망에 이르기까지 돌연변이의 정도에 따라서 다양한 증상를 나타내는 질환이다. 그러므로 질환이 의심되는 경우 반드시 조직검사를 고려하여야 한다. 사립체근병증이 있더라도 다른 증상이 없이 무호흡 증후군이나 저환기 증후군의 형태로 처음 진단되는 경우가 드물지만, 사립체근병증이 진단된 후에는 폐기능 검사를 통해 질환의 진행에 대한 예측이 필요하며, 호흡 부전이 발생할 가능성이 높은 경우 비침습적기계환기를 통해 환자를 치료 할 수 있다. 저자들은 초기 중추성 수면 무호흡 증후군으로 오인되었다가 저환기 증후군으로 진단하고, 원인질환으로 사립체근병증을 진단하였으며, 비침습적 기계환기를 통해 성공적으로 치료하여 추적관찰 중인 1례를 경험하였기에 보고하는 바이다.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 2008년도 춘계 학술발표회 제20권1호
• /
• pp.769-772
• /
• 2008

건설폐기물의 처리문제는 국가 사회적 문제로 제기되고 있으며 순환골재의 생산과정에서 발생하는 재생미분말은 전량 폐기 매립되고 있다. 재생미분말의 독성 시험결과 염기치환형 돌연변이원성을 포함하고 있다. 이와 같이 독성을 갖는 재생미분말이 매립 처분됨으로서 토양 및 지하수 오염등 2차 오염을 초래할 수 있다. 그러나 재생미분말을 재활용에 대한 연구가 매우 미흡한 실정이다. 본 연구에서는 재생미분말을 재활용하기 위한 방법으로 콘크리트의 혼화제를 활용하고자 시멘트 대신 재생미분말을 혼입하여 역학적 특성과 작업성을 비교 분석하였다. 실험은 CP, WCP, PCP로 배합비를 달리하여 공시체를 제작하여 실험을 실시하였다. CP은 재생미분말 혼입율에 따른 콘크리트 물리적 성질과 역학적 특성을 파악하고자 하였으며, WCP의 W자와 PCP의 P자는 각각 물과 혼화제의 이니셜로 슬럼프, 공기량을 표준배합에 맞게 제작하여 워커빌리티에 중점을 두고 재생미분말 혼입률에 따른 콘크리트의 역학적 특성을 보고자 하였다. CP는 치환율의 증가에 따라 강도 변화는 거의 일어나지 않았지만 슬럼프의 저하로 인해 워커빌리티가 좋지 않았다. WCP, PCP는 표준배합에 맞게 제작을 하여 실험한 결과 Plain에 비해 WCP는 강도저하가 일어났으며, PCP는 치환율이 10%일 때만 Plain과 거의 같은 값을 가지고 그 이상일 때는 강도저하가 일어났다.

• Tuberculosis and Respiratory Diseases
• /
• 제51권6호
• /
• pp.590-596
• /
• 2001

원발성 갑상선 기능저하증은 수면무호흡증후군의 원인 중 하나이다. 수면무호흡증후군 환자의 병력과 이학적 검사를 통하여 갑상선 기능저하의 가능성에 대한 충분한 평가가 필요하며, 또한 갑상선 기능저하증 환자도 수면무호흡증후군의 증상 및 가능성에 대한 고려가 필요하다. 그리고 본 증례와 같이 심장질환이 동반되어있을 때는 갑상선 호르몬 제재 단독투여 보다는 수면무호흡증후군에 의한 심각한 합병증을 예방하기 위하여 지속적 기도양압 치료를 동시에 적용하는 것이 좋다. 저자들은 원발성 갑상선 가능저하증과 확장형 심근증이 동반된 수변무호흡증후군 환자가 갑상선 호르몬 제재를 복용하고, 지속적 기도양압 치료적용 후 완전히 호전된 증례를 경험하였기에 보고하는 바이다.