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Construction of an Underground Heat Exchanger for Pig Housing (양돈용 지열교환기의 개발)

  • ;;H. J. Heege
    • Journal of Animal Environmental Science
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    • v.1 no.2
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    • pp.125-136
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    • 1995
  • To use the earth heat for the pig housing, an underground heat exchanger has constructed in depth of 2.5m and 20m length. The temperature of the outlet air was max. 8 kelvin higher than that of inlet air in winter season. In spite of the -7$^{\circ}C$ outside temperature, it could keep the air temperature from the earth tube above zero degree. The heating performance was maximum in value of 3.25Wh/㎥ and average of 1.75Wh/㎥ by the airflow volume of 340㎥/h. The slope of relative humidity from outlet air has shown gentler than that of inlet air. By using the underground heat exchanger, it would be possible to prepare an relatively uniform relative humidity in the swine stalls. The temperatures on the earth, where PVC pipes are buried, have shown 10~12$^{\circ}C$ on March. This can reduce the difference between day and night temperature during this season by using the underground heat exchanger.

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Swelling and Drug Release Characteristics of PVP Hydrogel Polymerized by $\gamma$-Irradiation Method (김마선 조사법으로 합성한 PVP하이드로겔의 팽윤과 약물방출특성)

  • 심창구;오정숙;신병철
    • YAKHAK HOEJI
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    • v.37 no.5
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    • pp.511-519
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    • 1993
  • The short and variabke transit of drug throught GI tracj and the inter-and intra-subject variations of the transit restrict the sustained drug absorption after oral adminstration. These restrictions may be solved by retaining the dosage forms in the stomach. Then the dosage form will act as a platform which releases the drug slowly and makes the GI absorption occur for a long time. In this study, as the platforms, PVP hydrogels were synthesized by chemical and y-irradiation method in the cylindrical test tube. The chemical method means the synthesis of the hydrogel by heating the mixed solution of N-vinyl-2-pyrrolidone [monomer], acrylated albumin [crosslinking agent], 2, 2'-agobis(2-methylpropionitrile) [initiator] and proxyphylline [drug] at $65^{\circ}C$ for 5 hr. The $\gamma$-irradiation method means the synthesis of the hydrogel by irradiation with $^{60}$ Co $\gamma$-ray of the mixed solution of the monomer, acrylated albumin, and flurbiprofen [drug] at room temperature with total 0.2 Mrad for 3 hr. Our intention is to design the hydrogel tablet (diameter : 1.20 cm, thickness : 0.60 cm) which swells in the gastric fluid after oral administration to such a size that passing through the pylorus could be inhibited during the period of drug release. After releasing drug, the hydrogel should be degraded by the enzymeatic digestion in the stomach, or by hydrolysis and eventually solubilized. Thus, in votro tests were performed to examine the factors that affect swelling and drug release from the PVP hydrogels. Experimental results show that the hydrogels swell to a size larger than the diameter of the pylorus(l.3$\pm$0.7 cm) and the hydrogel prepared by the chemical method is digested by pepsin. But the hydrogel prepared by the $\gamma$-irradiation method was not digested by the pepsin and just collapsed with time. Thus, the swelling of the hydrogel synthesized by $\gamma$-irradiation was independent albumin acrylation time and pepsin concentration. But drug content and radiation dose affected the swelling and drug release kinetics of the hydrogel. Drug release from the hydrigels was prolonged up to about 24 hr. Therefore, it was concluded that by adjusting these factors, the albumin-crosslinked PVP hydrogel synthesized by $\gamma$-irradiation method is expected to be retained in the stomach for up to 60hr and be a potential platform of drugs for long-term GI absorption.

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Quantitative Analysis of Bacillus amyloliquefaciens GR4-5 in Soil (Bacillus amyloliquefaciens GR4-5 균주의 토양 내 정량 분석)

  • Kim, Dayeon;Kim, Byung-Yong;Ahn, Jae-Hyung;Weon, Hang-Yeon;Kim, Sung-Il;Kim, Wan-Gyu;Song, Jaekyeong
    • Korean Journal of Organic Agriculture
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    • v.23 no.4
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    • pp.847-858
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    • 2015
  • Bacillus amyloliquefaciens GR4-5 was isolated from the rhizosphere soil of Korean ginseng and displayed broad-spectrum suppression of ginseng root rot pathogens. The survivability of B. amyloliquefaciens GR4-5 in soil was investigated under three different conditions; indoor, outdoor - of which soil was put in 14 mL tube after treatment - and field environments. Soil samples were collected over a four-week period from three experimental designs, and assessed for 16S rRNA gene copy number by quantitative polymerase chain reaction (qPCR). In outdoor condition, the 16S rRNA gene copy number of Bacillus spp. was 8.35 log copies g $soil^{-1}$ immediately after the GR4-5 treatment. Two weeks later, the 16S rRNA gene copy number of Bacillus spp. (6.70 log copies g $soil^{-1}$) was similar to that of the control (6.38 log copies g $soil^{-1}$). In indoor condition, the 16S rRNA gene copy number of Bacillus spp. maintained in a certain level for a longer period than those in outdoor and field. The 16S rRNA gene copy number of Bacillus spp. in field experiment was reduced faster than that of outdoor condition. Our results show that B. amyloliquefaciens GR4-5 can survive in bulk soil for 1 week, indicating its potential use as a biocontrol agent following 7 day application intervals. This study presents that outdoor microcosm system design could be a useful method to assess easily the survivability of beneficial microorganisms.

A Prospective Study for Risk Factors Predicting Postoperative Pulmonary Complications (수술 후 폐 합병증 발생의 위험 인자에 대한 연구)

  • Chon, Su Yeon;Kim, Yu Jin;Kyung, Sun Young;Ahn, Chang Hyeok;Lee, Sang Pyo;Park, Jeong Woong;Jeong, Sung Hwan
    • Tuberculosis and Respiratory Diseases
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    • v.62 no.6
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    • pp.516-522
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    • 2007
  • Background: Postoperative pulmonary complications are important problems that prolong the length of the hospital stay and increase patient mortality. However, our knowledge of the postoperative factors that increase the risk of these complications is less than complete. Methods: We conducted a prospective study to determine the risk factors for postoperative pulmonary complications. A total of 199 patients were referred to the Pulmonology Department for preoperative pulmonary evaluation. We reviewed the perioperative variables according to the National Surgical Quality Improvement Program (NSQIP). Postoperatively, we collected data on the occurrence of postoperative pulmonary complications and we evaluated the relationship between the perioperative variables and outcomes. Results: Twenty two patients (11%) had pulmonary complications; 6 had respiratory failure, 4 had pneumonia, 13 had pleural effusion and, 2 had atelectasis. Five variables were statistically significantly associated with pulmonary complications on the bivariate analyses. Multiple logistic regression analyses revealed that three of these variables were independently associated with an increased risk of pulmonary complications; a high cardiac risk index (OR 16.5, p=0.002), emergency surgery (OR 10.3, p=0.017), and thoracic/abdominal surgery (OR 3.8, p=0.047). Conclusion: The risk factors for postoperative pulmonary complications are a high cardiac risk index, emergency surgery and thoracic/abdominal surgery.

Urinary Estrone Sulfate for Monitoring Pregnancy of Dairy Cows

  • Yang, C.J.;Wu, L.S.;Tseng, C.M.;Chao, M.J.;Chen, P.C.;Lin, J.H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.16 no.9
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    • pp.1254-1260
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    • 2003
  • The purpose of this study firstly was conducted to establish a radioimmunoassay (RIA) of estrone sulfate ($E_1S$), secondly to monitor the reproductive status of dairy cows using their urine samples. Urine and blood samples were collected in series within a day from four pregnant Holstein-friesian cows to evaluate the relationship between $E_1S$ levels in blood and urine with or without urinary creatinine basis. The urine was then collected biweekly from three cows in estrous and those artificially inseminated; collection from pregnant cows was made on a monthly basis. Results indicated that sensitivity for the $E_1S$ RIA was 5 pg/tube and the recovery rate was 100%. The daily urinary creatinine concentrations fluctuated within a day, but changes were slighter in midday, whereas the changes of concentrations of $E_1S$ in urine were relatively smaller. The concentrations of serum $E_1S$ during the estrous cycle were undetectable due to the limitation of assay, but the urinary $E_1S$ level could be measured with no obvious changes during the cycle. The urinary $E_1S$ levels increased remarkably around 7.7 to 8.3 ng/ml, 80 to 100 days after pregnancy but the serum $E_1S$ levels did not elevate until 120 to 150 days. The level of $E_1S$ increased gradually during pregnancy and eventually reached its peak before parturition at around 40 ng/ml and finally decreased to its basal level 2 days postparturition. During pregnancy, $E_1S$ concentrations of urine increased earlier than those in blood. The correlation coefficients between urinary and serum $E_1S$ concentration during pregnancy and postparturm were higher than those adjusted with creatinine (creatinine ratio). The concentrations of $E_1S$ in urine could be maintained unchanged for 8 days storing the samples in room temperature, which was extended to 8 days when the samples were pretreated by boiling for 30 minutes or treated with autoclave. In conclusion urinary $E_1S$ concentrations can be used directly for monitoring the pregnant status and fetal viability of dairy cows and can assist accurate confirmation of pregnancy in cows at least 80 to 100 days after insemination much earlier than by serum $E_1S$.

Measurement of Electron Temperature and Number Density and Their Effects on Reactive Species Formation in a DC Underwater Capillary Discharge

  • Ahmed, Muhammad Waqar;Rahman, Md. Shahinur;Choi, Sooseok;Shaislamov, Ulugbek;Yang, Jong-Keun;Suresh, Rai;Lee, Heon-Ju
    • Applied Science and Convergence Technology
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    • v.26 no.5
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    • pp.118-128
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    • 2017
  • The scope of this work is to determine and compare the effect of electron temperature ($T_e$) and number density ($N_e$) on the yield rate and concentration of reactive chemical species ($^{\bullet}OH$, $H_2O_2$ and $O_3$) in an argon, air and oxygen injected negative DC (0-4 kV) capillary discharge with water flow(0.1 L/min). The discharge was created between tungsten pin-to pin electrodes (${\Phi}=0.5mm$) separated by a variable distance (1-2 mm) in a quartz capillary tube (2 mm inner diameter, 4 mm outer diameter), with various gas injection rates (100-800 sccm). Optical emission spectroscopy (OES) of the hydrogen Balmer lines was carried out to investigate the line shapes and intensities as functions of the discharge parameters such as the type of gas, gas injection rate and inter electrode gap distances. The intensity ratio method was used to calculate $T_e$ and Stark broadening of Balmer ${\beta}$ lines was adopted to determine $N_e$. The effects of $T_e$ and $N_e$ on the reactive chemical species formation were evaluated and presented. The enhancement in yield rate of reactive chemical species was revealed at the higher electron temperature, higher gas injection rates, higher discharge power and larger inter-electrode gap. The discharge with oxygen injection was the most effective one for increasing the reactive chemical species concentration. The formation of reactive chemical species was shown more directly related to $T_e$ than $N_e$ in a flowing water gas injected negative DC capillary discharge.

Short-term Hypothermic Preservation of CHO Cells Using Serum-Free Media (무혈청 배지를 이용한 CHO 세포의 단기 저온보존)

  • Byoun, Soon-Hwi;Park, Hong-Woo;Choe, Tae-Boo
    • KSBB Journal
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    • v.21 no.4
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    • pp.306-311
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    • 2006
  • Cell preservation is indispensable in animal cell culture process and should be established according to the cell characteristics. In this study, we experimented hypothermic preservation of CHO cells that is widely used in pharmaceutical industry to produce therapeutic proteins and established a stable method of preservation. The highest viability of CHO cells was obtained when the cells were preserved using rolling tube, which means the cells should be suspended to avoid the cell lumping during the preservation. Also, we obtained superior preservation result under the anaerobic condition. To evaluate the serum-free media as a preservation solution, we investigated cell growth after hypothermic preservation using serum-free media. High cell viability and normal cell growth was observed during 10 days using serum-free media. Moreover, we found that more effective preservation when ${\alpha}$-tocopherol and retinoic acid is added to media as an additive. In the case of 1 liter large scale hypothermic preservation using established protocol, cell viability and growth rate was obtained as good as small scale one. This study is considered to be helpful for hypothermic preservation of CHO cells and large scale hypothermic preservation may be available through the further studies.

Numerical Study for Flow Uniformity in Selective Catalytic Reduction(SCR) Process (SCR 공정에서 반응기 내부의 유동 균일화를 위한 수치적 연구)

  • Jung, Yu-Jin;Hong, Sung-Gil;Kim, Min-Choul;Lee, Jae-Jeong;Lee, Gang-Woo;Shon, Byung-Hyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.10
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    • pp.4666-4672
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    • 2011
  • Performance of NOx removal in SCR(Selective Catalytic Reduction) process depends on such various factors as catalyst factors (catalyst composition, catalyst form, space velocity, etc.), temperature of exhaust gas, and velocity distribution of exhaust gas. Especially the flow uniformity of gas stream flowing into the catalyst layer is believed to be the most important factor to influence the performance. In this research, the flow characteristics of a SCR process at design stage was simulated, using 3-dimensional numerical analysis method, to confirm the uniformity of the gas stream. In addition, the effects of guide vanes, baffles, and perforated plates on the flow uniformity for the inside and catalyst layer of the reactor were studied in order to optimize the flow uniformity inside the SCR reactor. It was found that the installation of a guide vane at the inlet duct L-tube part and the installation of a baffle at the upper part is very effective in avoiding chaneling inside the reactor. It was also found that additional installation of a perforated plate at the lower part of the potential catalyst layer buffers once more the flow for very uniform distribution of the gas stream.

Monitoring the Reproductive Status of Dairy Cows by Urinary Pregnanediol Glucuronide

  • Yang, C.J.;Wu, L.S.;Liu, S.H.;Lin, J.H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.17 no.4
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    • pp.460-466
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    • 2004
  • This study was undertaken with the aim to establish a reliable radioimmunoassay (RIA) system for urinary pregnanediol glucuronide (PdG) and to employ it for monitoring the reproductive status of dairy cows. Urine and blood samples were collected from the Holstein cows both pregnant and non-pregnant. The samples were then investigated for evaluating the relationship between progesterone ($P_{4}$) in blood and PdG in urine adjusted with or without urinary creatinine basis. Biweekly urine collection was employed for three cows in estrous and those artificially inseminated, while urine from pregnant cows was collected on a monthly basis. P_{4}$ and PdG levels were measured by enzymeimmunoassay (EIA) and RIA techniques, respectively. Our results indicated the sensitivity of PdG for RIA being 35 pg/tube and the recovery rate of 100%. Urinary creatinine concentrations also fluctuated within a day, but change at midday was not noteworthy. Regardless of the time of urination the change in concentrations of PdG was relatively smaller and did not vary significantly. The urinary PdG concentration showed periodic changes as that with serum P_{4}$ levels during the cow's estrus cycle. The correlation coefficient rose when creatinine level in urine was adjusted but the change was also not significant. The concentrations of PdG during the luteal phase were detected between 8.2 and 17.4 ng/ml, three to five times higher than that in the follicular phase. The concentration of PdG from pregnant cows (21 days after conception) was three to four times higher than in the nonpregnant cows. Our finding suggests that the determination of urinary PdG could be reliably employed for early pregnancy detection. The urinary PdG level continued to raise until 30 days pre-partum while the concentration reached its peak at 30 ng/ml, after which it started to fall 18 to 30 days before parturition and finally fell to its nadir value one week after parturition. As the correlation coefficient between the urinary PdG and serum P_{4}$ was higher than that corrected by urinary creatinine it can be suggested that the adjustment is not needed. The concentrations of urinary PdG could be maintained stably for 2 days in urine samples stored at room temperature and extended to 8 days when the samples were pretreated by boiling for 30 minutes. In conclusion urinary PdG concentration even without the need for creatinine basis adjustment can be used directly for monitoring the reproductive status of dairy cows.

10% Pentastarch Versus 5% Albumin Solution for Volume Expansion Following Cariopulmonary Bypass in Patients Undergoing Open Heart Surgery (개심수술후 혈량 증가를 위한 10% Pentastarch와 5% Albumin 용액의 비교연구)

  • 장병철
    • Journal of Chest Surgery
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    • v.27 no.3
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    • pp.177-186
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    • 1994
  • Pentastarch is a hydroxyethyl starch similar to hetastarch, but lower average molecular weight and fewer hydroxyethyl groups which result in enhanced enzymatic hydrolysis and faster renal elimination.This report was performed to compare the clinical efficacy and safety of 10 % pentastarch[Pentaspan , group I] for plasma volume expansion after open heart surgery with that of 5% albumin[Plasmanate, group II]. There were no statistically significant differences between the group I [n=18] and group II [n:19] in the preoperative parameters [age, sex, body weight] and operative parameters[bypass time, aorta cross clamping time]. During the first 24 hours after arrival of the patient in the surgical intensive care unit, colloid solution [500--1000 ml] was infused to maintain left atrial pressure of more than 8 mmHg, or cardiac index of 2.0 L/min/M2 of more. In results, there were 3 complications of hypotension immediately after infusion of 5 % albumin solution and 2 among the 3 patients were excluded for the study. However there was no complication after infusion of 10 % pentastarch solution. Hemodynamic responses to infusion was similar for both groups, although in group I a greater increase in both left atrial pressure[mean 1.8 versus 0.7 mmHg, p< 0.05] and right atrial pressure [mean 2.2 versus 1.7 mmHg, p < 0.05] was observed during infusion of the first 500 ml. There were no significant differences in any of the measured respiratory parameters[PaO2, intrapulmonary shunt, and effective lung compliance]. Homodilution with colloid significantly reduced hemoglobin [mean 1.2 versus 0.8 gm/dl], and serum protein and albumin level[total protein;4.8$\pm$ 0.5 versus 5.2 $\pm$0.5 gm/dl, p < 0.05: albumin: 3.2 $\pm$0.4 versus 3.6 $\pm$0.6 gm/dl, p < 0.05] by 6:00 AM on 1 day postoperatively, however there were no significant differences on 7 day postoperatively. The mean serum colloid osmotic pressure and osmolarity was similar in both group.There were no abnormal findings of liver function and kidney function in all the patients. There were no significant between-group differences in bleeding time, platelets, prothrombin time, activated partial thromboplastin time and amount of chest tube output measured on 1st and 7th postoperative day. These findings demonstrated that 10% pentastarch is more effective and safe for plasma volume expension than 5 % albumin solution with no adverse effects on coagulation. Also 10 % pentastarch is less expensive than 5 % albumin and it would appeare to be a reasonable first choice for plasma volume expansion.

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