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Oxidative Degradation of PCE/TCE Using $KMnO_4$ in Aqueous Solutions under Steady Flow Conditions (유동조건에서 $KMnO_4$도입에 따른 수용액중 PCE/TCE의 산화분해)

  • Kim, Heon-Ki;Kim, Tae-Yun
    • Economic and Environmental Geology
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    • v.41 no.6
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    • pp.685-693
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    • 2008
  • The rates of oxidative degradation of perchloroethene (PCE) and trichloroethene (TCE) using $KMnO_4$ solution were evaluated under the flow condition using a bench-scale transport experimental setup. Parameters which are considered to affect the reaction rates tested in this study were the contact time (or retention time), and the concentration of oxidizing agent. A glass column packed with coarse sand was used for simulating the aquifer condition. Contact time between reactants was controlled by changing the flow rate of the solution through the column. The inflow concentrations of PCE and TCE were controlled constant within the range of $0.11{\sim}0.21\;mM$ and $1.3{\sim}1.5\;mM$, respectively. And the contact time was $14{\sim}125$ min for PCE and $15{\sim}36$ min for TCE. The $KMnO_4$ concentration was controlled constant during experiment in the range of $0.6{\sim}2.5\;mM$. It was found that the reduction of PCE and TCE concentrations were inversely proportional to the contact time. The exact reaction order for the PCE and TCE degradation reaction could not be determined under the experimental condition used in this study. However, the estimated reaction rate constants assuming pseudo-1st order reaction agree with those reported based on batch studies. TCE degradation rate was proportional to $KMnO_4$ concentration. This was considered to be the result of using high inflow concentrations of reactant, which might be the case at the vicinity of the source zones in aquifer. The results of this study, performed using a dynamic flow system, are expected to provide useful information for designing and implementing a field scale oxidative removal process for PCE/TCE-contaminated sites.

Effect of Brown Seaweed Waste Supplementation on Lactational Performance and Endocrine Physiology in Holstein Lactating Cows (미역부산물의 첨가가 홀스타인 비유우의 비유성적과 내분비생리에 미치는 영향)

  • Lee, H.G.;Hong, Z.S.;Li, Z.H.;Xu, C.X.;Jin, X.;Jin, M.G.;Lee, H.J.;Choi, N.J.;Koh, T.S.;Choi, Yun-Jaie
    • Journal of Animal Science and Technology
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    • v.47 no.4
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    • pp.573-582
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    • 2005
  • This study was conducted to investigate effects of the brown seaweed waste(BSW) supplementation on milk production and related endocrine response in serum in Holstein dairy cows. A total of 14 Holstein dairy cows(initial mean live weight 625kg, average lactation days 225, Reproduction 2.4) were randomly allocated into control(basal diet) and treatment groups (4% BSW/basal diet) with 7 replications for 90 days. Dry matter intake was not affected by brown seaweed waste supplementation, but daily milk yield(kg) at the last experiment significantly increased (6.25kg) in treatment group compared with control group(p<0.05) at the last experiment. The plasma insulin-like growth factor(IGF)-1, triiodothyronine($T_3$) and thyroxine($T_4$) levels were significantly increased in treatment group compared with control group(p<0.05), although the concentration of plasma growth hormone(GH) was not significantly different. Milk composition was not significantly different between groups. The somatic cell count(SCC) in milk were significantly reduced in treatment group compared with control group(p<0.05), but antibodies(total IgG, G1, G2) were not significantly different between groups. Therefore we strongly believe that the increased milk yield is related to metabolic hormones as IGF-1, $T_3$ and $T_4$ and the mechanism of reducing SCC in milk must do more study related nonspecific immunsystem in the future.

Effects of Polyclonal Antibody Candidate to Adipocytes for Reducing Body Fat on Body Weight, Fecal Digestibility and Blood Metabolites in Pigs (체지방 감소 다클론 후보 항체가 비거세돈의 체중, 분 소화율 및 혈액 대사물질에 미치는 영향)

  • Choi, Chang-Weon;Baek, Kyung-Hoon;Cho, Sung-Back;Oh, Young-Kyoon;Hong, Seong-Koo;Choi, Chang-Bon
    • Journal of Animal Science and Technology
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    • v.52 no.5
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    • pp.375-382
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    • 2010
  • Twelve pigs were used to investigate the effects of polyclonal antibody candidate against abdominal (AAb) and subcutaneous adipocyte membrane proteins (SAb) on body weight, fecaldigestibility and blood metabolites. When AAb and SAb developed by Choi et al. (2010) were injected to pigs, the numerical increase in BW (body weight) occurred at 4 weeks post-treatment, but BW for an entire period was also increased, indicating that the BW increase may not be affected by the antibodies injection. Antibodies treatment did not affect (P>0.05) fecal digestibility of dry matter, crude protein, crude fat and crude fiber. Fecal digestibility of crude ash for control (no treatment) at 2 weeks decreased, and that for non-immunized serum treatmentgroup at 4 weeks post-treatment increased, respectively (P<0.05). However, fecal digestibility of crude ash for AAb and SAb groups did not significantly change. At 4 weeks after the antibodies treatment, blood urea N concentration for AAb and SAb groups was significantly increased (P<0.05). However, these increases may not be caused by the antibodies treatment because similar pattern in blood urea N concentration occurred before the antibodies treatment. Antibodies treatment did not affect concentration of plasma glucose and triglycerides (P<0.05). Compared with control, concentration of plasma total cholesterol for AAb and SAb groups at 4 weeks post-treatment was significantly (P<0.05) decreased. This may suggest that body fat reduction possibly occurs. In conclusion, the AAb and the SAb developed by Choi et al. (2010) may have safety in nutritional physiological metabolism in pigs. Further study on in vivo fat reduction of the antibodies against abdominal and subcutaneous adipocytes of pigs should be required for fat-reduced pork production.

Effects of Single and Repeated Electroconvulsive Shock on the Acetylcholine and Polyamine Contents in Temporal Cortex and Decorticated Cerebrum of Mice (경련성 전기충격에 의하여 나타나는 측뇌-피질과 피질을 제외한 대뇌의 Acetylcholine및 Polyamine 함량-변동에 관한 연구)

  • Choi, Sang-Hyun;Lee, Hak-Hee;Park, Chung-San;Chun, Boe-Gwun;Chun, Yeon-Sook
    • The Korean Journal of Pharmacology
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    • v.27 no.1
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    • pp.13-20
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    • 1991
  • There are some rather conflicting reports correlating ECS-induced changes of brain acetylcholine, and recently, Zawia and Bondy(1990) proposed the biological role of polyamine system in the long-term adaptive responses of brain to electrical stimulation. This study was undertaken to evaluate the effects of a single or repeated ECS(10mA, 100cps, 1sec; 5 ECS spread out over 9 days) on the brain acetylcholine(ACh) and polyamine contents of male mice. The ACh contents of temporal cortex(TCx) and decorticated cerebrum(dc-CB) were markedly increased by 79.9% and 49.4%, respectively, 10 and 30 min after ECS, and the increases were significantly attenuated with repeated 5 ECS, particularly in dc-CB. The putrescine concentrations of both TCx and dc-CB were little different and not affected by 1 ECS or 5 ECS. But the spermidine(Sd) concentration was higher in dc-CB and spermine(Sm) higher in TCx. While they were moderately decreased after 1 ECS, and their decreases were accentuated after 5 ECS, particularly in dc-CB.Sm(30mg/kg, i.p. inject. 30min before ECS) did not affect the ECS-induced increase of ACh content. Thease results suggest that both of brain ACh and polyamine may be implicated with the long-term adaptive responses to electrical stimulation

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Avascular Necrosis of Femoral Head on Bone Scan (대퇴골두 무혈성 괴사의 뼈스캔상의 병기)

  • Yang, Hyung-In;Kim, Eui-Jong;Kim, Deog-Yoon;Ryu, Kyung-Nam;Cho, Kyung-Sam
    • The Korean Journal of Nuclear Medicine
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    • v.28 no.2
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    • pp.206-213
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    • 1994
  • We studied 90 patients(179 femoral heads) with avascular necrosis of femoral head, who had been performed X-ray, bone scan and MRI to compare of the findings of AVN on bone scan between each other, retrospectively. The patients were 82 males and 9 females, their mean age was 45 years. Radiographic stages were classified by Steinberg modification, radionuclide stages were classified as followed; stage o(or type 0) : normal, stage 1 : faint ring like uptake around the femoral head, stage 2: intense ring like uptake, stage 3: irregular increased uptake with central photon defect, stage 4 : Intense diffuse increased uptake at femoral head and stage 5 : hip joint deformity with relatively mild increased uptake. The findings of MRI were classified according to extent, location, early or advanced lesion, signal intensity of the lesion and joint effusion. 156(87%) of 179 femoral heads had avascular necrosis, 68(75.5%) of 90 patients had bilateral AVN, 35 femoral heads had early stage and 120 had advanced stage. The detection rate of AVN by X-ray and bone scan were 85% (134), 91.6% (143), respectively. Early AVN with atypical types of bone scan showed larger extent, moderate to large amount of joint effusion, soft tissue hypertrophy within joint, and secondary degenerative changes. Bone scan had relatively high detection rate in the diagnosis of AVN of femoral head, and demonstrated various types depending on the disease stage.

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The Role of Hepatobiliary Scintiuaphy and Oral Cholecystography in Predicting the Performance of Laparoscopic Cholecystectomy (복강경담낭절제술에서 수술전 간담도신티그라피와 경구담낭조영술의 의의)

  • Won, Kyoung-Sook;Moon, Dae-Hyuk;Yang, Seoung-Oh;Han, Dong-Bok;Park, Cheol-Min;Lee, Moon-Gyu;Lee, Hee-Kyung;Park, Kwang-Min;Lee, Sung-Gyu;Ryu, Jin-Sook
    • The Korean Journal of Nuclear Medicine
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    • v.31 no.1
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    • pp.102-107
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    • 1997
  • Laparoscopic cholecystectorny can be performed safely in most patients with symptomatic cholelithiasis. Preoperative evaluation should assess the potential problems that affect the performance of laparoscopic cholecystectomy. Hepatobiliary scintigraphy or oral cholecystography can assess the gallbladder function and nonvisualization of gallbladder usually indicates acute or severe chronic cholecystitis. The purpose of this study was to evaluate the role of preoperative hepatobiliary scintigraphy or oral cholecystography in predicting the performance of laparoscopic cholecystectorny. The study group consists of 176 patients who underwent both hepatobiliary scintigraphy with Tc-99m DISIDA and oral cholecystography within one month before laparoscopic cholecystectomy. Nonvisualization of gallbladder was defined as persistent nonvisualization of gallbladder until 4 hours on hepatobiliary scintigraphy or 12 hours on oral cholecystography. Among 176 patients, gallbladder was not visualized in 38 patients on hepatobiliary scintigraphy and 41 patients on oral cholecystography. Concordance rate between hepatobiliary scintigraphy and oral cholecystography was 89.2%. The conversion rate to open cholocystectomy was significantly higher in patients with nonvisualization of gallbladder than in patients with gallbladder visualization(15.8% vs 2.9% on hepatobiliary scintigraphy, 12.2% vs 3.7% on oral cholecystography p<0.01 and p<0.05 respectively). The operative complication rate was also significantly higher in patients with nonvisualization of gallbladder (13.2% vs 2.9% on hepatobiliary scintigraphy, 14.6% vs 2.2% on oral cholecystography p<0.01 and p<0.001, respectively). Similarly, operation time was significantly prolonged in patients with nonvisualization of gallbladder ($88.8{\pm}41.9min$ vs $62.5{\pm}23.6min$ on hepatobiliary scintigraphy : p<0.001, $89.4{\pm}41.3$ min vs $61.8{\pm}22.8$ min on oral cholecystography : p<0.001). It is concluded that nonvisualization of gallbladder on hepatobiliary scintigraphy or oral cholecystography is a valuable preoperative clinical risk factor in predicting increased conversion rate to open cholecystectomy, increased operative complication and prolonged operation time.

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The Usefulness of LEUR Collimator for 1-Day Basal/Acetazolamide Brain Perfusion SPECT (1-Day Protocol을 사용하는 Brain Perfusion SPECT에서 LEUR 콜리메이터의 유용성)

  • Choi, Jin-Wook;Kim, Soo-Mee;Lee, Hyung-Jin;Kim, Jin-Eui;Kim, Hyun-Joo;Lee, Jae-Sung;Lee, Dong-Soo
    • The Korean Journal of Nuclear Medicine Technology
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    • v.15 no.1
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    • pp.94-100
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    • 2011
  • Purpose: Basal/Acetazolamide-challenged brain perfusion SPECT is very useful to assess cerebral perfusion and vascular reserve. However, as there is a trade off between sensitivity and spatial resolution in the selection of collimator, the selection of optimal collimator is crucial. In this study, we examined three collimators to select optimal one for 1-day brain perfusion SPECT. Materials and Methods: Three collimators, low energy high resolution-parallel beam (LEHR-par), ultra resolution-fan beam (LEUR-fan) and super fine-fan beam (LESFR-fan), were tested for 1-day imaging using Triad XLT 9 (TRIONIX). The SPECT images of Hoffman 3D brain phantom filled with 99mTc of 170 MBq and a normal volunteer were acquired with a protocol of 50 kcts/frame and detector rotation of 3 degree. Filterd backprojection (FBP) reconstruction with Butterworth filter (cut off frequencies, 0.3 to 0.5) was performed. The quantitative and qualitative assessments for three collimators were performed. Results: The blind tests showed that LESFR-fan provided the best image quality for Hoffman brain phantom and the volunteer. However, images for all the collimator were evaluated as 'acceptable'. On the other hand, in order to meet the equivalent signal-to-noise ratio (SNR), total acquisition time or radioactivity dose for LESFR-fan must have been increased up to almost twice of that for LEUR-fan and LEHR-par. The volunteer test indicated that total acquisition time could be reduced approximately by 10 to 14 min in clinical practice using LEUR-fan and LEHR-par without significant loss on image quality, in comparison with LESFR-fan. Conclusion: Although LESFR-fan provides the best image quality, it requires significantly more acquisition time than LEUR-fan and LEHR-par to provide reasonable SNR. Since there is no significant clinical difference between three collimators, LEUR-fan and LEHR-par can be recommended as optimal collimators for 1-day brain perfusion imaging with respect to image quality and SNR.

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Applications of "High Definition Digital Climate Maps" in Restructuring of Korean Agriculture (한국농업의 구조조정과 전자기후도의 역할)

  • Yun, Jin-I.
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.9 no.1
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    • pp.1-16
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    • 2007
  • The use of information on natural resources is indispensable to most agricultural activities to avoid disasters, to improve input efficiency, and to increase lam income. Most information is prepared and managed at a spatial scale called the "Hydrologic Unit" (HU), which means watershed or small river basin, because virtually every environmental problem can be handled best within a single HU. South Korea consists of 840 such watersheds and, while other watershed-specific information is routinely managed by government organizations, there are none responsible for agricultural weather and climate. A joint research team of Kyung Hee University and the Agriculture, forestry and Fisheries Information Service has begun a 4-year project funded by the Ministry of Agriculture and forestry to establish a watershed-specific agricultural weather information service based on "high definition" digital climate maps (HD-DCMs) utilizing the state of the art geospatial climatological technology. For example, a daily minimum temperature model simulating the thermodynamic nature of cold air with the aid of raster GIS and microwave temperature profiling will quantify effects of cold air drainage on local temperature. By using these techniques and 30-year (1971-2000) synoptic observations, gridded climate data including temperature, solar irradiance, and precipitation will be prepared for each watershed at a 30m spacing. Together with the climatological normals, there will be 3-hourly near-real time meterological mapping using the Korea Meteorological Administration's digital forecasting products which are prepared at a 5 km by 5 km resolution. Resulting HD-DCM database and operational technology will be transferred to local governments, and they will be responsible for routine operations and applications in their region. This paper describes the project in detail and demonstrates some of the interim results.

Impact and Prevalence of Renin-angiotensin System Gene Polymorphism of Renal Anomalies in Turner Syndrome (터너 증후군에서 신기형의 발생에 미치는 레닌-안지오텐신계 유전자 다형성의 영향)

  • Park Ji-Kyoung;Chung Young-Hee;Lee Jeong-Nyeo;Chung Woo-Yeong
    • Childhood Kidney Diseases
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    • v.7 no.1
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    • pp.52-59
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    • 2003
  • Purpose : The renin-angiotensin system(RAS) plays an important role in renal growth and development. We have studied the prevalence of renal anomalies and documented the association between karyotype and renal anomalies using IVP and ultrasonography. Furthermore, to investigate the impact of RAS gene polymorphism on renal anomaly in Turner syndrome, we examined the ACE I/D genotype, angiotensinogen(AGT) gene M235T, angiotensin receptor type 1(ATR) gene A1166C. Methods : Cytogenetic analysis was performed in 33 Turner syndrome patients on peripheral blood lymphocytes. Ultrasonography(US) of the kidneys and collecting system and intravenous pyelography(IVP) were perfomed in all patients. Nuclear scintigraphy{Tc 99m dimercaptosuccinic acid(DMSA) scan} was also performed for the definite renal diagnosis if indicated. And, ACE I/D genotype, angiotensinogen(AGT) gene M235T, angiotensin receptor type 1(ATR) gene A1166C were examined by PCR amplification of genomic DNA samples. Results : The prevalence of renal anolmalies in Turner syndrome was 36.4%(12/33). The Karyotype 45, X was observed in 18 of the 33 girls(54.5%), of whom 8(44.4%) had renal anomalies. Mosaic karyotypes were observed in 11(33.3%) and four(12.2%) had a non-mosaic structural aberration of the X chromosome. In this group 4(25.7%) had renal anomalies. More renal anomalies were associated with the 45, X karyotype than those with mosaic/structural abnormalities of X chromosome, but the difference was not statistically significant(P>0.05). And, there was no significant differences in the RAS gene polymorphism and allele frequencies between renal anomaly group and normal group in Turner syndrome. Conclusion : The prevalence of renal anolmalies in Turner syndrome was 36.4%. There is no significant differences in the RAS gene polymorphism and allele frequencies between the renal anomaly group and the normal group in Turner syndrome.

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Development of a Small Gamma Camera Using NaI(T1)-Position Sensitive Photomultiplier Tube for Breast Imaging (NaI (T1) 섬광결정과 위치민감형 광전자증배관을 이용한 유방암 진단용 소형 감마카메라 개발)

  • Kim, Jong-Ho;Choi, Yong;Kwon, Hong-Seong;Kim, Hee-Joung;Kim, Sang-Eun;Choe, Yearn-Seong;Lee, Kyung-Han;Kim, Moon-Hae;Joo, Koan-Sik;Kim, Byuug-Tae
    • The Korean Journal of Nuclear Medicine
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    • v.32 no.4
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    • pp.365-373
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    • 1998
  • Purpose: The conventional gamma camera is not ideal for scintimammography because of its large detector size (${\sim}500mm$ in width) causing high cost and low image quality. We are developing a small gamma camera dedicated for breast imaging. Materials and Methods: The small gamma camera system consists of a NaI (T1) crystal ($60 mm{\times}60 mm{\times}6 mm$) coupled with a Hamamatsu R3941 Position Sensitive Photomultiplier Tube (PSPMT), a resister chain circuit, preamplifiers, nuclear instrument modules, an analog to digital converter and a personal computer for control and display. The PSPMT was read out using a standard resistive charge division which multiplexes the 34 cross wire anode channels into 4 signals ($X^+,\;X^-,\;Y^+,\;Y^-$). Those signals were individually amplified by four preamplifiers and then, shaped and amplified by amplifiers. The signals were discriminated ana digitized via triggering signal and used to localize the position of an event by applying the Anger logic. Results: The intrinsic sensitivity of the system was approximately 8,000 counts/sec/${\mu}Ci$. High quality flood and hole mask images were obtained. Breast phantom containing $2{\sim}7 mm$ diameter spheres was successfully imaged with a parallel hole collimator The image displayed accurate size and activity distribution over the imaging field of view Conclusion: We have succesfully developed a small gamma camera using NaI(T1)-PSPMT and nuclear Instrument modules. The small gamma camera developed in this study might improve the diagnostic accuracy of scintimammography by optimally imaging the breast.

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