• 제목/요약/키워드: Time-activity curve

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A Study on the Removal of Ammonia by Using Peat Biofilter (미생물 활성토탄을 이용한 암모니아 제거에 관한 연구)

  • Choung, Youn Kyoo;Ahn, Jun Seong
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.14 no.3
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    • pp.655-668
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    • 1994
  • Conventional deodorization filters using soil and compost reach the capacity limitation of deodorization in short period, because its removal mechanism primarily depends on adsorption. Therefore, in this study the experiment was performed on the removal of ammonia which is a strong inorganic malodor, frequently emitted from night soil treatment plants and sewage treatment plants, by seeding activated sludges on the bio-peat containing higher organic contents, water conservation capacity, permeability and lower pressure drop. As a result, in raw peat filter natural ammonia outlet was observed in consequence of pH increase resulted from ammonia ionizing in liquid phase. Ammonia removal mechanism primarily depended on the adsorption onto the anion colloidal substances in peat. In peat bio-filter, theoretical ammonium salts ratio was higher than that of raw peat, resulted from slight pH increase by microorganism activity, however, the experimetal value of ammonia-nitrogen accumulated in bio-peat was lower than that of raw peat because of nitrification by nitrifying bacteria. In the initial reaction period, adsorption was predominant in the ammonia removal mechanism, but nitrification was conspicuous after the middle period. Mass balance of nitrogen was established using experimental data of input $NH_3$ loading, output $NH_3$ loading, $NH_4{^+}$-N, $NO_x$-N, and Org-N. The critical time of unsteady state, which is the maximum activating point of microorganism in bio-filter, was determined using experimental data, and the ammonia adsorption curve was computed using regression analysis. On the basis of the results obtained by above analysis, the delay days for the saturation of adsoption capacity in peat bio-filter was calculated.

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Dose Calculation for the Buckler Remote Afterloading System (Buchler 강내조사장치의 선량계산에 대한 연구)

  • Chung Weon Kuu;Kim Soo Kon;Kang Jeong Ku;Lee Jeong Ok;Moon Sun Rock;Kim Seung Kon
    • Radiation Oncology Journal
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    • v.14 no.3
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    • pp.247-253
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    • 1996
  • Purpose : The dose calculation program for the Buckler type remote after-loading system was developed. This program also can be used to calculate dose for various sealed sources. Materials and Methods : We determined the source length and distribution by dividing the program disk to 72 points. The dose rate for the each program disk and source was calculated. The dose rate table for the xy coordinate was established. The dose rate for the interesting points of the patient were calculated by using this table, We also made isodose curve from this calculations. Results : The storage size for the dose rate table were increased. But the calculation of the dose rate for the patient were carried out rapidly. So we could get real time calculation. Conclusion : By using this program, we could calculate the dose rate for the various points of the patient quickly and accurately. This program will be useful for the treatment with various linear sources.

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Comparison of Sorption Characteristics of Several Soybean Varieties (콩 품종별 흡습특성 비교)

  • Kim, Dong-Hee;Yum, Cho-Ae;Kim, Woo-Jung
    • Applied Biological Chemistry
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    • v.33 no.1
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    • pp.14-17
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    • 1990
  • Seven varieties of soybeans(Paldal, Danyeob, Jangbaek, Baegun, Jangyeob and 2 cultivars of Local 1 and Local 2) were investigated to compare the sorption characteristics during storage of various relative humidities. The sorption isotherm curve determined at RH range of $33{\sim}92\;%$ and $4^{\circ}C$ and $25^{\circ}C$ showed that moisture contents of soybeans was higher at $4^{\circ}C$ than those values at $25^{\circ}C$ for overall water activities of 0.33{\sim}0.92$. The Paldal was the highest moisture content at $4^{\circ}C$ while that value of Baegun was the highest at $25^{\circ}C$. The change in moisture content with storage time was expressed by log(dw/dt)=b log(t)+log a and the value of (dw/dt)${\times}10^3$ was decreased logarithmically. The Paldal was comparatively the highest initial absorption rate and the value of -b in seven varieties decreased as the relative humidity increased from 33 % to 92 %.

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In vitro and in vivo Antibacterial Activities and Pharmacokinetics of 8-Fluorociprofloxacin and Ciprofloxacin (8-Fluorociprofloxacin과 Ciprofloxacin의 시험관내 및 생체내 항균효과와 약물동태의 비교)

  • 최경업;정용환;김제학
    • YAKHAK HOEJI
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    • v.37 no.3
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    • pp.235-242
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    • 1993
  • 8-Fluorociprofloxacin(8-FCP) is an investigational quinolone derivative that is substituted with fluorine at the C-8 position of ciprofloxacin(CP). It was found that the in vitro activity of 8-FCP against Gram(+) bacteria was more potent that of CP, but the opposite against Gram(-) bacteria was true. However, 8-FCP showed better in vivo efficacy than CP against representative Gram(-) organisms, E. coli and K pneumoniae. In an attempt to seek for factors causing this discrepancy in the antibacterial activities, a comparative pharmacokinetic study of 8-FCP and CP was conducted in mice and rats treated either intravenously or orally at a single dose of 30 mg/kg. The pharmacokinetic parameters in mice were as follows; the mean peak serum concentrations(C$_{max}$) following i.v. and oral doses were 12.4 and 5.3 $\mu\textrm{g}$/ml for 8-FCP, and 9.5 and 2.5 $\mu\textrm{g}$/ml for CP, respectively. The terminal half-life(t$_{1/2\beta}$) was 72.9 min for 8-FCP, and 98.2 min for CP, and the oral bioavailability(F) was 89.9% for 8-FCP, and 50.5% for CP. In rats, the mean ($\pm$SD) $C_{max}$ after i.v. administration were 11.6$\pm$1.6 $\mu\textrm{g}$/ml for 8-FCP, and 10.2$\pm$1.3 $\mu\textrm{g}$/ml for CP, whereas oral administration produced $C_{max}$ of 5.9$\pm$1.8 $\mu\textrm{g}$/ml for 8-FCP and 1.1$\pm$0.9 $\mu\textrm{g}$/ml for CP, respectively. The t$_{1/2\beta}$ was 67.9$\pm$8.4 min for 8-FCP, and 76.4$\pm$7.2 min for CP. The F was 88.6$\pm$6.3% for 8-FCP, and 40.7$\pm$6.5% for CP. Marked differences were observed between the two quinolones in the $C_{max}$ and the area under the concentration-time curve obtained after oral administration in mice and rats. The extent of 8-FCP absorption in both mice and rats was approximately 2-fold higher than that of CP, suggesting that the fluorine atom attached to C-8 plays an important role in facilitating oral absorption from the gastrointestinal tract.

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Early Gonadogenesis and Sex Differentiation in the Korean Rose Bitterling, Rhodeus uyekii

  • Goo, In Bon;Kim, Jung Eun;Kim, Myung Hun;Choi, Hye-Sung;Kong, Hee Jeong;Lee, Jeong Ho;Park, In-Seok
    • Development and Reproduction
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    • v.20 no.4
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    • pp.289-296
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    • 2016
  • This report describes the sex differentiation of the Korean rose bitterling, Rhodeus uyekii, from hatching to 170 days post-hatch (DPH) in relation to total length (TL), body weight (BW), and integral water temperature (IWT). The growth curve of TL from just hatching to 83 DPH was $5.144e^{0.045t}$ ($R^2=0.961$; t, time), and that of BW was $2.398e^{0.086t}$ ($R^2=0.725$). Primordial germ cells (PGCs) were observed at 17 DPH (7.9 mm TL, 3.74 mg BW, $374^{\circ}C$ IWT), and thereafter began to protrude into the peritoneal cavity. At 21 DPH ($9.2{\pm}0.14mm$ TL, $4.8{\pm}0.07mg$ BW, $462^{\circ}C$ IWT), some PGCs contained condensed chromatin and oocyte were observed in meiotic prophase. In contrast to the ovaries, which grew gradually after sexual differentiation, testes began multiplying at 25 DPH (10.1 mm TL, 5.42 mg BW, $550^{\circ}C$ IWT), when testicular differentiation was first identified, and multiplied continuously thereafter. At 33 DPH (11.2 mm TL, 10.5 mg BW, $726^{\circ}C$ IWT), the developing testes contained spermatogonia that exhibited mitotic activity. No spermatocyte or sperm cell was observed until 83 DPH (18.9 TL, 48.2 mg BW, $1,826^{\circ}C$ IWT). At 170 DPH (32.5 mm TL, 270.1 mg BW, $3,740^{\circ}C$ IWT), which was the end point of this study, the mature ovaries showed germinal vesicle breakdown, while the mature testes contained observable spermatocytes and sperm cells. These results allow us to identify the sex differentiation type of the Korean rose bitterling as differentiated gonochoristic.

Utilization of [6]-gingerol as an origin discriminant marker influencing melanin inhibitory activity relative to its content in Pinellia ternata (반하(Pinellia ternata)에서의 [6]-gingerol 함량과 멜라닌 저해 활성에 영향을 미치는 원산지 판별 마커로의 활용)

  • An, Ju Hyeon;Won, Hyo Jun;Seo, Soo-Kyung;Kim, Doo-Young;Ku, Chang-Sub;Oh, Sei-Ryang;Ryu, Hyung Won
    • Journal of Applied Biological Chemistry
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    • v.59 no.4
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    • pp.323-330
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    • 2016
  • Pinellia ternata Breitenbach, the natural medicinal plant of the Araceae family, is a perennial plant originated from the East Asia, but also widely distributed in Europe and North America. Its tuber is used as traditional medicine for treatment of various diseases such as vomiting, inflammation, and traumatic injury. Pharmacological studies revealed that P. ternata possesses anticonvulsant, anti-tumor, insecticidal, and cytotoxic activities. Despite being well-known as the useful medicinal plant, there is no reliable, standardized method for origin discrimination. Ultra performance liquid chromatography-photodiode array detector and quadrupole time of flight-mass spectrometry based metabolite-profiling was applied to explore significant metabolite for origin discrimination between Korean and Chinese P. ternata. One compound was isolated from Korean P. ternata using repeated ODS column chromatography by bioactivity guided fractionation, and determined as [6]-gingerol according to the results of spectroscopic data including nuclear magnetic resonance and MS. This compound was selected as cosmeceutical biomarker by fingerprints, and it was associated to melanin inhibitory effect determining its origin authenticity. Furthermore, the calibration curve of biomarker was prepared using validated method for the comparison of content between Korean and Chinese P. ternata. This is the report to address the selection and successful validation of the discriminant metabolite for confirmation of Korean P. ternata.

MicroRNA-23a: A Novel Serum Based Diagnostic Biomarker for Lung Adenocarcinoma

  • Lee, Yu-Mi;Cho, Hyun-Jung;Lee, Soo-Young;Yun, Seong-Cheol;Kim, Ji-Hye;Lee, Shin-Yup;Kwon, Sun-Jung;Choi, Eu-Gene;Na, Moon-Jun;Kang, Jae-Ku;Son, Ji-Woong
    • Tuberculosis and Respiratory Diseases
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    • v.71 no.1
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    • pp.8-14
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    • 2011
  • Background: MicroRNAs (miRNAs) have demonstrated their potential as biomarkers for lung cancer diagnosis. In recent years, miRNAs have been found in body fluids such as serum, plasma, urine and saliva. Circulating miRNAs are highly stable and resistant to RNase activity along with, extreme pH and temperatures in serum and plasma. In this study, we investigated serum miRNA profiles that can be used as a diagnostic biomarker of non-small cell lung cancer (NSCLC). Methods: We compared the expression profile of miRNAs in the plasma of patients diagnosed with lung cancer using an miRNA microarray. The data from this assay were validated by quantitative real-time PCR (qRT-PCR). Results: Six miRNAs were overexpressed and three miRNAs were underexpressed in both tissue and serum from squamous cell carcinoma (SCC) patients. Sixteen miRNAs were overexpressed and twenty two miRNAs were underexpressed in both tissue and serum from adenocarcinoma (AC) patients. Of the four miRNAs chosen for qRT-PCR analysis, the expression of miR-23a was consistent with microarray results from AC patients. Receiver operating characteristic (ROC) curve analyses were done and revealed that the level of serum miR-23a was a potential marker for discriminating AC patients from chronic obstructive pulmonary disease (COPD) patients. Conclusion: Although a small number of patients were examined, the results from our study suggest that serum miR-23a can be used in the diagnosis of AC.

Evaluation of Regional Wall Motion by Phase Analysis of Radionuclide Cardiac Blood Pool Scintigrams in Coronary Artery Disease Patients (관상동맥질환 환자에서 방사성동위원소 위상분석에 의한 심근 국소 운동 평가)

  • Yi, Gang-Wook;Chung, June-Key;Oh, Byeong-Hui;Park, Young-Bae;Lee, Myung-Chul;Lee, Young-Woo;Koh, Chang-Soon
    • The Korean Journal of Nuclear Medicine
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    • v.21 no.2
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    • pp.167-174
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    • 1987
  • Among noninvasive approaches for the evaluation of left ventricular performance, radionuclide ventriculography (RVG) has been shown to be of particular values. Phase analysis, recently introduced as more objective means for evaluating the temporal sequence of systolic ventricular wall motion than cine image of RVG comprises a pixel by pixel Fourier transformation of the time activity curve of a multiple gated acquisition equilibrium blood pool study. To examine the regional wall motion of ventricles in myocardial infarctions, we evaluated the phase image and histogram constructed for each ventricle by total phase angle range and full width of half maximum (FWHM). This study consisted of 7 normal subjects and 23 subjects with acute myocardial infarction. Contrast ventriculography and coronary angiography was performed in all partients with myocardial infarction. And we compared the result of phase analysis with cine image of RVG and examined the interrelationship between phase analysis and contrast ventriculography with coronary angiography. The results were as follows; 1) The total phase angle range and FWHM of LV phase histogram in myocardial infarction ($86^{\circ}\;and\;32^{\circ}$, repectively) were wider than those in normal control ($38^{\circ}\;and\;18^{\circ}$, respectively p<0.01). 2) RV phase angle range and FWHM in patients with right coronary artery (RCA) occlusion ($79^{\circ}\;and\;37^{\circ}$, respectively) were wider than those in normal control ($39^{\circ}\;and\;18^{\circ}$, respectively p<0.001) and the patients without RCA occlusion ($52^{\circ}\;and\;19^{\circ}$, respectively p<0.01). 3) Phase analysis was more sensitive (95%) than cine image of RVG (70%) for the detection of regional wall motion abnormality of LV.

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Multiple Linear Analysis for Generating Parametric Images of Irreversible Radiotracer (비가역 방사성추적자 파라메터 영상을 위한 다중선형분석법)

  • Kim, Su-Jin;Lee, Jae-Sung;Lee, Won-Woo;Kim, Yu-Kyeong;Jang, Sung-June;Son, Kyu-Ri;Kim, Hyo-Cheol;Chung, Jin-Wook;Lee, Dong-Soo
    • Nuclear Medicine and Molecular Imaging
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    • v.41 no.4
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    • pp.317-325
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    • 2007
  • Purpose: Biological parameters can be quantified using dynamic PET data with compartment modeling and Nonlinear Least Square (NLS) estimation. However, the generation of parametric images using the NLS is not appropriate because of the initial value problem and excessive computation time. In irreversible model, Patlak graphical analysis (PGA) has been commonly used as an alternative to the NLS method. In PGA, however, the start time ($t^*$, time where linear phase starts) has to be determined. In this study, we suggest a new Multiple Linear Analysis for irreversible radiotracer (MLAIR) to estimate fluoride bone influx rate (Ki). Methods: $[^{18}F]Fluoride$ dynamic PET scans was acquired for 60 min in three normal mini-pigs. The plasma input curve was derived using blood sampling from the femoral artery. Tissue time-activity curves were measured by drawing region of interests (ROls) on the femur head, vertebra, and muscle. Parametric images of Ki were generated using MLAIR and PGA methods. Result: In ROI analysis, estimated Ki values using MLAIR and PGA method was slightly higher than those of NLS, but the results of MLAIR and PGA were equivalent. Patlak slopes (Ki) were changed with different $t^*$ in low uptake region. Compared with PGA, the quality of parametric image was considerably improved using new method. Conclusion: The results showed that the MLAIR was efficient and robust method for the generation of Ki parametric image from $[^{18}F]Fluoride$ PET. It will be also a good alternative to PGA for the radiotracers with irreversible three compartment model.

Image-based Absorbed Dosimetry of Radioisotope (영상기반 방사성동위원소 흡수선량 평가)

  • Park, Yong Sung;Lee, Yong Jin;Kim, Wook;Ji, Young Hoon;Kim, Kum Bae;Kang, Joo Hyun;Lim, Sang Moo;Woo, Sang-Keun
    • Progress in Medical Physics
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    • v.27 no.2
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    • pp.86-92
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    • 2016
  • An absorbed dose calculation method using a digital phantom is implemented in normal organs. This method cannot be employed for calculating the absorbed dose of tumor. In this study, we measure the S-value for calculating the absorbed dose of each organ and tumor. We inject a radioisotope into a torso phantom and perform Monte Carlo simulation based on the CT data. The torso phantom has lung, liver, spinal, cylinder, and tumor simulated using a spherical phantom. The radioactivity of the actual absorbed dose is measured using the injected dose of the radioisotope, which is Cu-64 73.85 MBq, and detected using a glass dosimeter in the torso phantom. To perform the Monte Carlo simulation, the information on each organ and tumor acquired using the PET/CT and CT data provides anatomical information. The anatomical information is offered above mean value and manually segmented for each organ and tumor. The residence time of the radioisotope in each organ and tumor is calculated using the time activity curve of Cu-64 radioactivity. The S-values of each organ and tumor are calculated based on the Monte Carlo simulation data using the spatial coordinate, voxel size, and density information. The absorbed dose is evaluated using that obtained through the Monte Carlo simulation and the S-value and the residence time in each organ and tumor. The absorbed dose in liver, tumor1, and tumor2 is 4.52E-02, 4.61E-02, and 5.98E-02 mGy/MBq, respectively. The difference in the absorbed dose measured using the glass dosimeter and that obtained through the Monte Carlo simulation data is within 12.3%. The result of this study is that the absorbed dose obtained using an image can evaluate each difference region and size of a region of interest.