• Korean Journal of Plant Resources
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• v.27 no.5
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• pp.546-555
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• 2014

The final aim of this study is to develop a biofiltration system integrated with plant vegetation for improving indoor air quality effectively depending on indoor space and characteristics. However, to approach this final goal, several requirements such as constant pressure drops (PDs) and soil moisture contents (SMCs), which influence the capacity design for a proper ventilation rate of biofiltration system, should be satisfied. Thus, this fundamental experiment was carried out to adjust a proper wind speed and to ensure a stabilization of initial SMCs within biofilter for uniform distribution of SMCs and PDs, and for normal plant growth, especially avoiding root stress by wind. Therefore, we designed horizontal biofliter models and manufactured them, and then calculated the ventilation rate, air residence time, and air-liquid ration based on the biofilter depending on three levels of wind speed (1, 2, and $3cm{\cdot}s^{-1}$). The relative humidity (RH) and PD of the humidified air coming out through the soil within the biofilter, and SMC of the soil and plant growth parameters of lettuce and duffy fern grown within biofilter were measured depending on the three levels of wind speed. As a result of wind speed test, $3{\cdot}sec^{-1}$ was suitable to keep up a proper RH, SMC, and plant growth. Thus, the next experiment was set up to be two levels of initial SMCs (low and high initial SMC, 18.5 and 28.7%) within each biofilter operated and a non-biofiltered control (initial SMC, 29.7%) on the same wind speed ($3cm{\cdot}sec^{-1}$), and measured on the RH and PD of the air coming out through the soil within the biofilter, and SMC of the soil and plant growth parameters of Humata tyermani grown within biofilter. This result was similar to the first results on RHs, SMCs, and PDs keeping up with constant levels, and three SMCs did not show any significant difference on plant growth parameters. However, two biofiltered SMCs enhanced dry weights of the plants slightly than non-biofiltered SMC. Thus, the stability of this biofiler system keeping up major physical factors (SMC and PD) deserved to be adopted for designing an advanced integrated biofilter model in the near future.

• Economic and Environmental Geology
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• v.38 no.5 s.174
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• pp.535-545
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• 2005

Environmental survey from some abandoned metal mine areas was undertaken on to assess the risk of adverse health effects on human exposure to arsenic influenced by past Au-Ag mining activities. Elevated levels of As were found in tailings from the studied mine areas. This high concentration may have a impact on soils and waters around the tailing piles. In order to perform the human risk assessment, chemical analysis data of soils, rice grains and waters fur As have been used. The HQ values fer As via the rice grain and groundwater consumption were significantly higher compared with other exposure pathways in all metal mine areas. However, there were minimal soil and water dermal contact risks. The resulting Hl values of As from the Dongil, Okdong and Hwacheon mine areas were higher than 5.0, and their toxic risk due to drinking water and rice grain was strong in these mine areas. The cancer risk of being exposed to As by the rice grain route from the Dongil, Okdong and Hwacheon mine areas was $5.2\times10^{-4},\;6.0\times10^{-4}\;and\;8.1\times10^{-4}$, respectively. The As cancer risk via the exposure pathway of drinking water from these mine areas exceeded the acceptable risk of 1 in 10,000 fer regulatory purposes. Thus, the daily intakes of groundwater and rice grain by the local residents from the Dongil, Okdong and Hwacheon mine areas can pose a potential health threat if exposed by long-term arsenic exposure.

• Journal of Chest Surgery
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• v.39 no.7 s.264
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• pp.505-510
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• 2006

Background: Small animal cardiopulmonary bypass (CPB) model would be a valuable tool for investigating path-ophysiological and therapeutic strategies on bypass. The main advantages of a small animal model include the reduced cost and time, and the fact that it does not require a full scale operating environment. However the rat CPB models have a number of technical limitations. Effective maintenance and control of core temperature by a heat exchanger is among them. The purpose of this study is to confirm the effect of rectal temperature maintenance using a heat exchanger of cardioplegia system in cardiopulmonary bypass model for rats. Material and Method: The miniature circuit consisted of a reservoir, heat exchanger, membrane oxygenator, roller pump, and static priming volume was 40 cc, Ten male Sprague-Dawley rats (mean weight 530 gram) were divided into two groups, and heat exchanger (HE) group was subjected to CPB with HE from a cardioplegia system, and control group was subjected to CPB with warm water circulating around the reservoir. Partial CPB was conducted at a flow rate of 40 mg/kg/min for 20 min after venous cannulation (via the internal juglar vein) and arterial cannulation (via the femoral artery). Rectal temperature were measured after anesthetic induction, a ter cannulation, 5, 10, 15, 20 min after CPB. Arterial blood gas with hematocrit was also analysed, 5 and 15 min after CPB. Result: Rectal temperature change differed between the two groups (p<0.01). The temperatures of HE group were well maintained during CPB, whereas control group was under progressive hypothermia, Rectal temperature 20 min after CPB was $36.16{\pm}0.32^{\circ}C$ in the HE group and $34.22{\pm}0.36^{\circ}C$ in the control group. Conclusion: We confirmed the effect of rectal temperature maintenance using a heat exchanger of cardioplegia system in cardiopulmonary bypass model for rats. This model would be a valuable tool for further use in hypothermic CPB experiment in rats.

• Tuberculosis and Respiratory Diseases
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• v.52 no.5
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• pp.475-484
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• 2002

Background : Unresectable non-small cell lung cancer has a poor response to chemotherapy and has an unfortunate prognosis. More effective and less toxic cytotoxic agents are needed to improve the outcome of these patients. The efficacy and safety of vinorelbine monotherapy in these advanced lung cancer patients was evaluanted. Materials and Methods : Sixteen patients with non-small cell lung cancer in stage III or IV, who received vinorelbine alone as an initial anticancer chemotherapy from June 1996 to December 2000 were enrolled in this study. Vinorelbine was given intravenously at a dose 30mg/$m^2$ every week. Results : A mong the sixteen patients, six had a partial response(38%) and the median survival was 16 weeks. The median response duration was 27 weeks (95% CI 6-47), and the time to progression was 16 weeks(95% CI 6-26). Among a total of 112 cycles, neutropenia(WHO grade 3 or 4) and anemia(grade 3) occurred in 9% and 3%, respectively. Only 1 patient required hospitalization for neutropenic fever. Non-hematologic toxicity was minor and was easily controlled. Conclusion : Vinorelbine monotherapy was well tolerated, and moderately effective in patients with advanced non-small cell lung cancer.

• Tuberculosis and Respiratory Diseases
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• v.56 no.2
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• pp.187-197
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• 2004

Background : Nitric Oxide (NO) is a multi-faceted molecule with dichotomous regulatory roles in many areas of biology. NO can promote apoptosis in some cells, whereas it inhibits apoptosis in other cell types. This study was performed to characterize NO-induced cell death in lung epithelial cells and to investigate the roles of cell death regulators including iron, bcl-2 and p53. Methods : A549 cells were used for lung epithelial cells. SNP (sodium nitroprusside) and SNAP (S-nitroso-N-acetyl- penicillamine) were used for NO donor. Cytoxicity assay was done by MTT assay and crystal violet assay. Apoptotic assay was done by fluorescent microscopy after double staining with propidium iodide and hoecst 33342. Iron inhibition study was done with RBCs and FeSO4. For bcl-2 study, bcl-2 overexpressing cells (A549-bcl-2) were used and for p53 study, Western blot analysis and p53 functionally knock-out cells (A549-E6) were used. Results : SNP and SNAP induced dose-dependent cell death in A549 cells and fluorescent microscopy revealed that SNAP induced apoptosis in low doses but necrosis in high doses while SNP induced exclusively necrotic cell death. Iron inhibition study using RBCs and FeSO4 significantly blocked SNAP-induced cell death. And also SNAP-induced cell death was blocked by bcl-2 overexpression. Finally, we found that SNAP activate p53 by Western blot analysis and that SNAP-induced cell death was decreased in the abscence of p53. Conclusion : In lung epithelial cells, NO can induce cell death, more precisely apoptosis in low doses and necrosis in high doses. And iron, bcl-2, and p53 play important roles in NO-induced cell death.

• Clinical and Experimental Pediatrics
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• v.48 no.2
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• pp.197-203
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• 2005

Purpose : Changes in metalloproteinases(MMP) activity have been demonstrated in several disease states, including rheumatoid arthritis and tumor metastasis. More importantly, increased myocardial MMP activity has been reported to occur in both clinical and experimental forms of dilated cardiomyopathy. There was no report about MMP in adriamycin(ADR)-induced cardiomyopathy. The purpose of this study was to investigate gene expression of MMP and tissue inhibitor of metalloproteinases(TIMP) in ADR-induced cardiomyopathy and clarify the relationship between MMP and cytokines. Methods : Male Sprague-Dawley rats were divided into two groups. The first group was control. The second group was given intraperitoneal injections of ADR(5 mg/kg) twice a week over two weeks. Serum concentrations of MMP, TIMP, interleukin(IL)-6 and tumor necrosis factor(TNF)-${\alpha}$ were measured. RNA extraction was performed from frozen rat hearts. Reverse transcription polymerase chain reaction(RT-PCR) was employed. cDNA Microarray analysis was performed by using a set of 5,184 sequence-verified rat cDNA clones. Results : Serum MMP and TIMP levels were not significantly different between the two groups. IL-6 was $36.8{\pm}2.8pg/mL$ and TNF-${\alpha}$ $2.2{\pm}2.7pg/mL$ in the ADR group. They were significantly higher than in the control group. Serum MMP correlated significantly with TNF-${\alpha}$(r=0.41, P<0.05). There was no gene expression of MMP, IL-6 or TNF-${\alpha}$ in the hearts of both groups. Gene expression of TIMP was significantly depressed in the hearts of the ADR group. Conclusion : These results suggested a potential role for TNF-${\alpha}$ in the regulation of extracellular matrix remodeling in ADR induced cardiomyopathy. Rapid screening of multiple decreased gene expression by DNA chip may be a useful diagnostic test to detect early cardiac injury before developing ADR induced cardiomyopathy.

• Radiation Oncology Journal
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• v.14 no.4
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• pp.265-279
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• 1996

Damage produced by radiation elicits a complex response in mammalian cells, including growth rate changes and the induction of a variety of genes associated with growth control and apoptosis. At doses of 10,000 cGy or greater, the exposed individual was killed in a matter of minutes to a couple of days, with symptoms consistent with pathology of the central nervous system(CNS) including degenerative changes. The nature of the damage in irradiated cells underlies the unique hazards of ionizing radiation. Radiation injury to CNS is a rare event in clinical medicine, but it is catastrophic for the patient in whom it occurs. The incidence of cerebral necrosis has been reported as high as 16% for doses greater than 6,000 cGy. In this study, the effect of radiation on brain tissue was studied in vivo. Jun and p53 genes in the rat brain were induced by whole body irradiation of rat with 600Co in doses between 1 Gy and 100 Gy and analyzed for expression of jun and p53 genes at the postirradiation time up to 6 hours. Northern analyses were done using 1.8 Kb & 0.8 Kb-pGEM-2-JUN/Eco RI/Pst I fragments, 2.0 Kb-php53B/Bam HI fragment and ,1.1 Kb-pBluescript SK--ACTIN/Eco RI fragment as the digoxigenin or [${\alpha}^{32}P$] dCTPlabeled probes for Jun, p53 and ${\beta}$-actin genes, respectively. Jun gene seemed to be expressed near the threshold levels in 1 hour after irradiation of $^{60}$Co in dose less than 1 Gy and was expressed in maximum at 1 hour after irradiation of $^{60}$Co in dose of 30 Gy. Jun was expressed increasingly with time until 5 or 6 hours after irradiation of $^{60}$Co in doses of 1 Gy and 10 Gy. After irradiation of $^{60}$Co in dose between 20 Gr and 100 Gy, the expression of Jun was however increased to peak in 2 hours and decreased thereafter. p53 gene in this study also seemed to be expressed near the threshold levels in 1 hour after irradiation of $^{60}$Co in dose less than 1 Gy and was expressed in maximum at 6 hours after irradiation of $^{60}$Co in dose of 1 Gy, p53 was expressed increasingly with time until 5 or 6 hours after irradiation of $^{60}$Co in dose between 1 Gy and 40 Gy. After irradiation of $^{60}$Co in doses of 50 Gy and 100 Gy, the expression of p53 was however increased to peak in 2 hours and decreased thereafter. The expression of Jun and p53 genes was not correlative in the brain tissue from rats. It seemed to be very important for the establishment of the optimum conditions for the animal studies relevant to the responses of genes inducible on DNA damage to ionizing radiation in mammalian cells. But there are many limitations to the animal studies such as the ununiform patterns of gene expression from the tissue because of its complex compositions. It is necessary to overcome the limitations for development of in situ Northern analysis.

• Journal of Chest Surgery
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• v.37 no.1
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• pp.11-18
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• 2004

Background: We tested the effect of indomethacine and total spinal anesthesia on the improvement of placental flow during cardiopulmonary bypass on fetal lamb. Material and Method: Twenty fetuses at 120 to 150 days of gestation were subjected to bypass via trans-sternal approach with a 12 G pulmonary arterial cannula and 14 to 18 F venous cannula for 30 minutes. All ewes received general anesthesia with ketamine. In all the fetuses, no anesthetic agents were used except muscle relaxant. Ten served as a control group in which placenta was worked as an oxygenator during bypass (Control group). The remainder worked as an experimental group in which pretreatment with indomethacine and total spinal anesthesia was performed before bypass with the same extracorporeal circulation technique as control group (Experimental group). Observations were made every 10 minutes during a 30-minute bypass and 30-minute post bypass period. Result: Weights of the fetuses ranged from 2.2 to 5.2 kg. In Control group, means of arterial pressure decreased from 44.7 to 14.4 mmHg and means of Pa$CO_2$ increased from 61.9 to 129.6 mmHg at each time points during bypass. Flow rate was suboptimal (74.3 to 97.0 $m\ell$/kg/min) during bypass. All hearts fibrillated immediately after the discontinuation of bypass. On the contrary, in Experimental group, means of arterial pressure reamined higher (45.8 to 30 mmHg) during bypass (p<0.05). Means of Pa$CO_2$ were less ranging from 59.8 to 79.4 mmHg during bypass (P<0.05). Flow rates were higher (78.8 to 120.2 $m\ell$/kg/min) during bypass (p<0.05). There were slower deterioration of cardiac function after cessation of bypass. Conclusion: In this study, we demonstrated that the placental flow was increased during fetal cardiopulmonary bypass in the group pretreated with indomethacine and total spinal anesthesia. However, further studies with modifications of the bypass including a creation of more concise bypass circuit, and a use of axial pump are mandatory for the clinical application.

• Journal of Biosystems Engineering
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• v.8 no.1
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• pp.47-60
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• 1983

상온통풍(常溫通風)을 이용(利用)한 In-bin drying에 대(對)한 많은 실험결과(實驗結果)에 의(依)하면 우리나라 10월(月)의 기상조건(氣象條件)은 저온건조(低溫乾燥) system에 적합(適合)한 건조능력(乾燥能力)을 가지고 있는 것으로 나타났다. 최근(最近) Computer를 이용(利用)한 Simulation model이 개발(開發)되어 건조현상(乾操現象)에 관(關)한 경제적(經濟的)이고 효율적(效率的)인 분석(分析)이 가능(可能)하게 되었다. 이러한 분석결과(分析結果)에 의(依)하면 초기함수율(初期含水率)이 높은 벼를 Full-bin을 이용(利用)한 상온통풍건조(常溫通風乾操)를 할 경우(境遇) 건조기간(乾燥期間)이 길어지며 bin내(內)의 상층부(上層部) 곡물(穀物)이 변질(變質)되는 문제점(問題點)이 발생(發生)하였다. 또한 벼의 수확작업체계(收穫作業體系)가 관행(慣行) 및 Binder작업체계(作業體系)에서 점차(漸次) Combine작업체계(作業體系)로 전환(轉換)되어감에 따라 포장(圃場)에서의 건조(乾燥)가 어려우며 예취(刈取), 탈곡작업과정(脫穀作業過程)에서의 기계적(機械的)인 곡물(穀物) 손실(損失)을 줄이기 위(爲)하여 함수율(含水率)이 비교적(比較的) 높은 벼를 수확(收穫)하여야 한다. 본(本) 연구(硏究)의 목적(目的)은 상온통풍건조(常溫通風乾燥)에 있어서 건조능력(乾燥能力)을 증가(增加)시키기 위(爲)하여 곡물(穀物)을 일정기간(一定期間) 나누어서 bin에 넣고 건조(乾燥)를 하는 Layer drying의 Simulation model을 개발(開發)하고 이 Model에 수원지방(水原地方)의 7년간(年間) 평균(平均) 기상자료(氣象資料)를 입력(入力)시켜 곡물(穀物)의 초기함수율(初期含水率), 투입량(投入量), 투입기간(投入期間)의 변화(變化)에 따른 Layer drying현상(現象)을 규명(糾明)하는데 있다. Simulation에 사용(使用)된 bin의 크기는 직경(直徑) 2m, 깊이 1.5m이며 송풍(送風)팬의 용량(容量)은 0.5HP이었다. Simulation분석(分析) 결과(結果)를 요약(要約)하면 다음과 같다. (1) Layer drying의 Simulation model을 개발(開發)하였으며 이 Model은 벼의 상온통풍건조(常溫通風乾燥) 실험(實驗)에서 함수량(含水量) 변화(變化)의 이론치(理論値)와 실제실험치(實際實驗値)가 잘 일치(一致)하였다. (2) 곡물투입기간(穀物投入期間) 1일(日)을 Full-bin drying으로 간주(看做)할 때 Layer drying의 건조성능(乾燥性能)은 Full-bin보다 높은 것으로 나타났다. (3) 연속송풍(連續送風)(24시간(時間))을 할 경우(境遇) 곡물투입기간(穀物投入期間)이 증가(增加)함에 따라 건조기간(乾燥期間)의 감소경향(減少傾向)은 단속송풍(斷續送風)인 경우(境遇)보다 적었지만 건조기간(乾燥期間)은 단축(短縮)되었다. 그러나 건조(乾燥)에너지의 소모(消耗)는 단속송풍(斷續送風)일 때보다 크게 나타났다. (4) 단속송풍(斷續送風)(9 : 00AM~6 : 00PM)일 경우(境遇) 곡물투입기간(穀物投入期間)을 증가(增加)시키면 건조기간(乾燥期間)이 크게 줄어 들었다. (5) 곡물(穀物)의 초기함수율(初期含水率)이 21% 이하(以下)일 경우(境遇) 연속(連續) 및 단속송풍(斷續送風)에서 건조기간(乾燥期間)의 차이(差異)가 별로 없었다. (6) 곡물(穀物)의 초기함수율(初期含水率)이 높으면 Full-bin drying에서는 상부층(上部層)에 곡물(穀物)이 변질(變質)될 우려(憂慮)가 있으나 Layer drying에서는 곡물투입량(穀物投入量)을 조절(調節)하면 이것을 방지(防止)할 수 있었다. (7) 건조(乾燥)가 완료(完了)된 후(後) 층별(層別) 최종곡물(最終穀物) 함수율(含水率)은 모든 건조조건(乾燥條件)에서 동일(同一)하였으나 bin의 하부층(下部層)은 과건조(過乾燥) 물상(物象)을 일으켰다.

• Economic and Environmental Geology
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• v.50 no.4
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• pp.257-266
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• 2017

Batch experiments were performed to develop the method for the pH reduction of recycled aggregate by using $scCO_2$ (supercritical $CO_2$), maintaining the pH of extraction water below 9.8. Three different aggregate types from a domestic company were used for the $scCO_2$-water-recycled aggregate reaction to investigate the low pH maintenance of aggregate during the reaction. Thirty five gram of recycled aggregate sample was mixed with 70 mL of distilled water in a Teflon beaker, which was fixed in a high pressurized stainless steel cell (150 mL of capacity). The inside of the cell was pressurized to 100 bar and each cell was located in an oven at $50^{\circ}C$ for 50 days and the pH and ion concentrations of water in the cell were measured at a different reaction time interval. The XRD and SEM-EDS analyses for the aggregate before and after the reaction were performed to identify the mineralogical change during the reaction. The extraction experiment for the aggregate was also conducted to investigate the pH change of extracted water by the $scCO_2$ treatment. The pH of the recycled aggregate without the $scCO_2$ treatment maintained over 12, but its pH dramatically decreased to below 7 after 1 hour reaction and maintained below 8 for 50 day reaction. Concentration of $Ca^{2+}$, $Si^{4+}$, $Mg^{2+}$ and $Na^+$ increased in water due to the $scCO_2$-water-recycled aggregate reaction and lots of secondary precipitates such as calcite, amorphous silicate, and hydroxide minerals were found by XRD and SEM-EDS analyses. The pH of extracted water from the recycled aggregates without the $scCO_2$ treatment maintained over 12, but the pH of extracted water with the $scCO_2$ treatment kept below 9 of pH for both of 50 day and 1 day treatment, suggesting that the recycled aggregate with the $scCO_2$ treatment can be reused in real construction sites.