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Feasibility Test of Biohydrogen Production from Food Waste (음식물쓰레기의 수소발효 타당성 평가)

  • Han, Sun-Kee;Kim, Sang-Hyoun;Shin, Hang-Sik
    • Journal of the Korea Organic Resources Recycling Association
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    • v.11 no.3
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    • pp.87-95
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    • 2003
  • Although extensive studies were conduced on hydrogen fermentation of organic wastewaters, little is known about biohydrogen production from organic solid wastes. The leaching-bed reactor treating food waste by heat-shocked anaerobic sludge was, therefore, operated at D of 2.1, 3.6, 4.5 and $5.5d^{-1}$ to find optimal D for hydrogen production. Successful operation of a reactor can be accomplished when it is operated at proper dilution rate (D). Operation at high D leads to the washout of biomass in the reactor while operation at low D leads to product inhibition due to the accumulation of excess VFA. These appear to limit the production of hydrogen to reach a higher level. All the reactors showed that, on day 1-3, hydrogen production was dominant and VFA concentration was higher than ethanol. Butyrate and acetate were major components of VFAs over the whole operation, though lactate was very high on day 1-2. Compared with other D values, D of $4.5d^{-1}$, resulted in higher butyrate/acetae (B/A) ratios during the fermentation. The trend of B/A ratios was similar to the hydrogen production, suggesting that butyrate formation favored hydrogen production. Ethanol increased significantly from day 4 when hydrogen Production stopped. It indicated that heat-shocked sludge was able to induce a metabolic flow from hydrogen-and acid-producing pathway to solvent-producing pathway. Operation at D of $4.5d^{-1}$ led to higher fermentation efficiency (58%) than those (51.5, 55.3 and 53.7%) at 2.1, 3.6 and $5.5d^{-1}$. The COD removed was convened to hydrogen (10.1%), VFA (30.9%), and ethanol (17.0%).

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Outpatient Chest Tube Management with Using a Panda Pneumothorax Set with a Heimlich Valve (Panda Pneumothorax Set with Heimlich Valve에 의한 외래에서의 흉관 관리)

  • Choi, Soon-Ho;Lee, Mi-Kyung;Ryu, Dae-Woong
    • Journal of Chest Surgery
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    • v.42 no.4
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    • pp.497-501
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    • 2009
  • Background: Prolonged air leakage and pleural fluid drainage from a chest tube may delay removing the chest tube after a patient undergoes video-assisted thoracoscopic wedge resection and the patient is otherwise ready for discharge. We reviewed 37 outpatients patients who were being managed with a postoperative chest tube (a Panda Pneumothorax set with a Heimlich valve). Material and Method: From January 2005 to December 2007, 294 patients underwent video-assisted thoracoscopic wedge resections & pleurodesis. Of them, 37 patients met the criteria for outpatient chest drainage management with using a Panda Pneumothorax set with a Heimlich valve. The patients received written instructions, and they demonstrated competence with using the Panda system. The patients returned for chest tube removal after satisfactory resolution of their air leak and pleural fluid drainage. Result: The patients discharged with a Panda pneumothorax set had a longer duration of hospital stay (mean: 10.3$\pm$1.7 days, range: 11 to 17 days) as compared with the patients without a Panda pneumothorax set (mean: 6.2$\pm$1.5 days, range: 4 to 7 days). The chest tube was removed successfully from the patients with a Panda pneumothorax set at an average of 9.8$\pm$1.6 days (range: 9$\sim$18 days) after discharge. There were no major complications. Four patients experienced minor complications. Thirty six patients (97.3%) experienced uneventful and successful outpatient chest tube management. Conclusion: Successful postoperative outpatient chest tube management with using the Panda set was accomplished in 36 selected patients. This program resulted in a substantially reduced hospital cost and enhanced patient satisfaction by allowing earlier discharge.

Characterization of Pretreatment for Barley straw by Alkaline Solutions (염기 용매를 이용한 보릿짚의 전처리 특성)

  • Kim, Kyoung-Seob;Kim, Jun Seok
    • Korean Chemical Engineering Research
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    • v.50 no.1
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    • pp.18-24
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    • 2012
  • Lignocellulose is difficult to hydrolyze due to the presence of lignin and the technology developed for cellulose fermentation to ethanol is not yet economically viable. However, recent advances in the extremely new field of biotechnology for the ethanol production are making it possible to use of Agriculture residual biomass, e.q., Barley straw, because of their several superior aspects as Agriculture residual biomass; low lignin, high contents of carbohydrates. Barley straw consists of 39.78% cellulose (glucose), 22.56% hemicelluloses and 19.27% lignin. Pretreatment of barley straw using NaOH pretreatment solutions concentration with 2%, temperature $85^{\circ}C$ and reaction times 1 hr were investigates. $NH_4OH$ pretreatment condition was solutions concentration with 15%, temperature $60^{\circ}C$, and reaction times 24hr were investigates. Furthermore, enzymatic saccharification using cellulose at $50^{\circ}C$, pH 4.8, 180 rpm for conversion of cellulose contained in barley straw to monomeric sugar. The pretreatment of barley straw using NaOH and $NH_4OH$ can significantly improve enzymatic saccharification of barley straw by extract more lignin and increasing its accessibility to hydrolytic enzymes. The result showed NaOH pretreatment extracted yield of lignin was 24.15%. $NH_4OH$ pretreatment extracted yield of lignin was 29.09%. Shaccharification of barley straw pretreatment by NaOH for 72hr and pH 4.8 result in maximum glucose concentration 15.39g/L (58.40%) and by $NH_4OH$ for 72hr and pH 4.8 result in maximum glucose concentration 16.01g/L (64.78%).

$^{99m}Tc-DTPA$ Galactosyl Human Serum Albumin Scintigyaphy in Mushiroom Poisoning Patient : Comparison with Liver Ultrasonography (버섯 중독 환자에서의 $^{99m}Tc-galactosyl$ human serum albumin (GSA) scintigraphy 소견 : 간초음파 소견과의 비교)

  • Jeong, Shin-Young;Lee, Jea-Tae;Bae, Jin-Ho;Chun, Kyung-Ah;Ahn, Byeong-Cheol;Kang, Young-Mo;Jeong, Jae-Min;Lee, Kyu-Bo
    • The Korean Journal of Nuclear Medicine
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    • v.37 no.4
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    • pp.254-259
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    • 2003
  • $^{99m}Tc-galactosyl$ human serum albumin (Tc-GSA) is a radiopharmaceutical that binds to asialoglycoprotein receptors, which are specifically present in the hepatocyte membrane. Because these receptors are decreased in hepatic parenchymal damage, the degree of Tc-GSA accumulation in the liver correlates with findings of liver function test. Hepatic images were performed with Tc-GSA in patients with acute hepatic dysfunction by Amantia Subjunquillea poisoning, and compared with these of liver ultrasonography (USG). Tc-GSA (185 MBq, 3 mg of GSA) was injected intravenously, and dynamic images were recorded for 30 minutes. Time-activity curves for the heart and liver were generated from regions of interest for the whole liver and precordium. Degree of hepatic uptake and clearance rate of Tc-GSA were generated by visual interpretation and semiquantitative analysis parameters (receptor index : LHL15 and index of blood clearance : HH15). Visual assessment of GSA scintigraphy revealed mildly decreased liver uptake in all of subjects. The mean LHL15 and HH15 were 0.886 and 0.621, graded as mild dysfunction in 2, and mild to moderate dysfunction in 1 subject. In contrast, liver USG showed no remarkable changes of hepatic parenchyme. Tc-GSA scintigraphy was considered as a useful imaging modality in the assessment of the hepatic dysfunction.

The Effects of Water Extract of Polygonatum Odoratum (Mill) Druce on Insulin Resistance in 90% Pancreatectomized Rats (90% 췌장 절제 백서에서 둥굴레뿌리의 물추출물이 인슐린 저항성에 미치는 영향)

  • Park, Sun-Min;Ahn, Seung-Hee;Choi, Mi-Kyung;Choi, Soo-Ran;Choi, Soo-Bong
    • Korean Journal of Food Science and Technology
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    • v.33 no.5
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    • pp.619-625
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    • 2001
  • We determined whether the supplementation of Polygonatum Odoratum (Mill) Druce (POD) extract had a good effect on insulin resistance in peripheral tissues of 90% pancreatectomized (Px) and sham-operated (Sham) male Sprague Dawley rats. Px and Sham rats were divided into two groups; one group daily consumed 0.3 g of POD extracts per 1 ㎏ body weight for two months, and the other group had a placebo. All rats freely consumed a 40% fat diet. At the end of the experiment, a euglycemic hyperinsulinemic (EH) clamp was performed in a fasting, awake, and unstressed state to determine insulin resistance. At EH clamp, body weights were higher in Sham rats than Px rats, and serum glucose levels of baseline were affected by diabetic status and POD administration. Serum insulin concentrations were higher in Sham rats than Px rats, and POD administration decreased them in Sham rats compared to P. Glucose disposal rates in peripheral tissues increased with POD in both Px (n=10) and Sham (n=10) rats. But glycogen deposits in soleus muscle increased with POD administration in Px and Sham rats, and total glycogen synthase activity and fraction velocity were higher in POD groups. Triglyceride contents in quadriceps muscles decreased with POD in Px rats. In conclusions, POD improves insulin resistance by enhancing glucose utilization with increasing glycogen deposit and decreasing triglyceride contents in muscles.

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Axenic Culture Production and Growth of a Dinoflagellate, Cochlodinium polykrikoides (적조 와편모조류, Cochlodinium polykrikoides의 순수분리 및 성장)

  • SEO Pil-Soo;LEE Sang-Jun;Kim Yoon;LEE Jeong-Ho;KIM Hak-Gyoon;LEE Jae-Dong
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.31 no.1
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    • pp.71-76
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    • 1998
  • To know the antibiotic specificity of a Dinoflagellate, Cochlodinium polykrikoides, we investigated the survival time of C. polykrikoides against several concentrations of antibiotics and judged the selective specificity of antibiotics based on the $LT_50$ ($50\%$ of lethal time). The result showed that C. polykrikoides was sensitive to tetracycline and chloramphenicol, and resistant to polymixin-B, ampicillin, penicillin-G, dihydrostreptomycin, and neomycin. In the case of sensitive antibiotics to C. polykrikoides, tetracycline and chloramphenicol, the safety concentrations of both antibiotics were determined and the antibiotic specificity based or the plotted survival curve was analyzed. Before antibiotic treatment, we tested the antibiotic susceptibility of the contaminated bacterial population in tile culture of C. polykrikoides, and decided the proper kinds of antibiotics and concentrations before percoll-centrifugation. By percoll-centrifugation, we reduced bacteria, removed fungi, collected the algal pellet, and made axonic culture by antibiotic cascade procedure based on the result of antibiotic susceptibility test. We observed that axonic C. polykrikoides culture entered the logarthmic phase of growth when cell density was over 740 cells/ml and propagated to 5,800 cells/ml maximally. Divisions per day, k value of C. polykrikoides represented a good index for growth at the low density of cells. There was a highest k value shift before reaching to the logarithmic phase. We suggested that the preceeding highest k value shift stage is a good indicator for accurate broadcasting for red. tide blooming in the field, and the stage is also a good time for controlling red tide blooming in the filed, either.

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A Development of Automatic Lineament Extraction Algorithm from Landsat TM images for Geological Applications (지질학적 활용을 위한 Landsat TM 자료의 자동화된 선구조 추출 알고리즘의 개발)

  • 원중선;김상완;민경덕;이영훈
    • Korean Journal of Remote Sensing
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    • v.14 no.2
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    • pp.175-195
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    • 1998
  • Automatic lineament extraction algorithms had been developed by various researches for geological purpose using remotely sensed data. However, most of them are designed for a certain topographic model, for instance rugged mountainous region or flat basin. Most of common topographic characteristic in Korea is a mountainous region along with alluvial plain, and consequently it is difficult to apply previous algorithms directly to this area. A new algorithm of automatic lineament extraction from remotely sensed images is developed in this study specifically for geological applications. An algorithm, named as DSTA(Dynamic Segment Tracing Algorithm), is developed to produce binary image composed of linear component and non-linear component. The proposed algorithm effectively reduces the look direction bias associated with sun's azimuth angle and the noise in the low contrast region by utilizing a dynamic sub window. This algorithm can successfully accomodate lineaments in the alluvial plain as well as mountainous region. Two additional algorithms for estimating the individual lineament vector, named as ALEHHT(Automatic Lineament Extraction by Hierarchical Hough Transform) and ALEGHT(Automatic Lineament Extraction by Generalized Hough Transform) which are merging operation steps through the Hierarchical Hough transform and Generalized Hough transform respectively, are also developed to generate geological lineaments. The merging operation proposed in this study is consisted of three parameters: the angle between two lines($\delta$$\beta$), the perpendicular distance($(d_ij)$), and the distance between midpoints of lines(dn). The test result of the developed algorithm using Landsat TM image demonstrates that lineaments in alluvial plain as well as in rugged mountain is extremely well extracted. Even the lineaments parallel to sun's azimuth angle are also well detected by this approach. Further study is, however, required to accommodate the effect of quantization interval(droh) parameter in ALEGHT for optimization.

Biological Treatment of Piggery Liquid Manure by Malodor Reducing Bacteria (악취 저감용 세균에 의한 돈분뇨의 생물학적 처리)

  • Quan, Xiao-Tian;Shin, Jae-Hyeong;Wang, Yan-Qing;Choi, Min-Gyung;Kim, Sang-Min;Kim, Soo-Ki
    • Journal of Life Science
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    • v.32 no.12
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    • pp.971-978
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    • 2022
  • Sulfur-oxidizing, ammonium-oxidizing, and nitrogen-oxidizing media were used to isolate bacteria to degrade malodor gas effectively in piggery manure or soil. Twelve different strains were isolated: Paenibacillus amylolyticus, Rhodococcus jostii, Rhodococcus qingshengii, Rhodococcus opacus, Alcaligenes faecalis, Alcaligenes faecalis, Kastia adipate, Kastia adipata, Microbacterium oxydans, Halomonas campisalis, Acinetobacter oleivorans, and Micrococcus luteus. By inoculating each strain in the piggery liquid manure by 1%, the pH in most strain treatments was maintained at 8.0. Total bacterial counts were maintained at 7.3~7.9 log CFU/ml until 15 days, and then they dropped dramatically down to 5.1~5.5 log CFU/ml. On the 30th day, the treatment group inoculated with Rhodococcus opacus SK2659 showed a relatively high level of ammonium nitrogen removal, which was 39% of that of the control group. When Rhodococcus opacus SK2659 was inoculated, H2S concentration after 100 days was 3.23% compared with the control (no inoculation), suggesting that Rhodococcus opacus SK2659 is an excellent strain for removing malodor gas. The gas production of the treatments was lower than that of the control. The total accumulated amount of gas production in most strain treatments was a quarter of the gas production compared to the control throughout the experimental periods. Acinetobacter oleivorans SK2675 showed the lowest level at 12.39% compared to the control in gas production. In conclusion, the use of mixture strains, such as Rhodococcus opacus SK2659 and Acinetobacter oleivorans SK2675 isolated in this study could increase the efficacy of malodor gas reduction in the biological treatment of piggery manure.

Alteration of Anaerobic Bacteria and S. mutans Count in Oral Cavity after Occlusal Stabilization Appliance Use (교합안정장치 사용에 따른 구강 내 혐기성 세균과 S. mutans의 변화)

  • Byun, Jin-Seok;Suh, Bong-Jik
    • Journal of Oral Medicine and Pain
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    • v.32 no.4
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    • pp.375-381
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    • 2007
  • Occlusal stabilization appliance is one of the most common treatment option for management of temporomandibular disorders. It acts in oral cavity for several hours per day, and usually it will take at least 6 months to 2 years of total wearing periods to take a treatment goal. In the oral cavity, occlusal stabilization appliance, unintentional manner, is able to acts as a reservoir of bacteria and protect bacteria from saliva and oxygen. This condition is so favorable to many bacteria such as S. mutans and other anaerobes, usually have been reported as causative factors of dental caries, periodontal disease and oral malodor. In this study, we investigated anaerobic bacteria and S. mutans count before and after occlusal stabilization appliance use to evaluate the possible role of occlusal stabilization appliance as protector of these bacteria. Four men(average 27.5 years) wore maxillary occlusal stabilization appliance at each night(average 9 hours) for 5 days. we swabbed saliva-plaque mixed sample at 3 different site(maxillary left 2nd molar, maxillary left central incisor, mandibular left 2nd molar) before and after occlusal stabilization appliance use. Each samples were plated in (1) anaerobic blood agar medium, (2) selective S. mutans medium(MS-MUTV) and incubated in anaerobic chamber($CO^2$ 10%, $37^{\circ}C$) for 72 hours. Each bacterial colony forming unit(CFU) were counted with naked eyes. From obtained data, we can conclude as follows: 1. There was some changes about anaerobic bacteria and S. mutans count in oral cavity after occlusal stabilization appliance use. 2. The number of anaerobic bacteria was significantly increased at maxillary 2nd molar(P=0.003), maxillary central incisor(P=0.020) after occlusal stabilization appliance use compared with before. 3. Occlusal stabilization appliance use itself had indirect effect to increase the number of anaerobic bacteria at other uncovered opponent tooth site. 4. The number of S. mutans was significantly increased at maxillary 2nd molar(P=0.043), maxillary central incisor (P=0.049) after occlusal stabilization appliance use compared with before. 5. Occlusal stabilization appliance use itself had not any effect on the number of S. mutans at other uncovered opponent tooth site.

A study of hydrocarbon SCR(selective catalytic reduction) on Ag/γ-Al2O3 catalyst (Ag/γ-Al2O3 촉매상에서 탄화수소-SCR(Selective Catalytic Reduction) 연구)

  • Kim, Moon-Chan;Lee, Cheal-Gyu
    • Analytical Science and Technology
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    • v.18 no.2
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    • pp.139-146
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    • 2005
  • Removal of NO contained in automobile exhaust gas was accomplished by the non-selective catalyst reduction method. The catalysts were prepared through loading of a specific amount of Ag into ${\gamma}-Al_2O_3$. The conversion of $NO_x$ was studied by varying the temperatures, $O_2$ concentrations and $SO_2$ concentrations for the prepared catalysts. The influence of the structure of catalyst to $NO_x$ conversion was followed through the analysis of the physical properties of the prepared catalysts. Experiments were conducted on each of the catalysts by varying the reaction conditions to find an optimum condition. The catalyst $Ag/{\gamma}-Al_2O_3$ shows a highest $NO_x$ conversion when the Ag content was 2 wt% and a reaction temperature of about $450^{\circ}C$. and after conducting the experiments, samples of before and after experiments analyzed using XRD, XPS, TPR, and UV-Vis DRS experiments. The result indicated that when Ag oxide content could not be maintained well at high temperatures $NO_x$ conversion decreased.