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Characterization of Microbial Diversity of Metal-Reducing Bacteria Enriched from Groundwater and Reduction/Biomineralization of Iron and Manganese (KURT 지하심부 지하수 내 토착 금속환원미생물의 종 다양성 및 철/망간의 환원과 생광물화작용)

  • Kim, Yumi;Oh, Jong-Min;Jung, Hea-Yeon;Lee, Seung Yeop;Roh, Yul
    • Economic and Environmental Geology
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    • v.47 no.4
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    • pp.431-439
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    • 2014
  • The purposes of this research were to investigate the enrichment of metal-reducing bacteria from KURT groundwater and the identification of the microbial diversity by 16S rRNA as well as to examine microbial Fe(III)/Mn(IV) reduction and to analyze morphological features of interactions between microbes and precipitates and their mineralogical composition. To cultivate metal-reducing bacteria from groundwater sampled at the KURT in S. Korea, different electron donors such as glucose, acetate, lactate, formate, pyruvate and Fe(III)-citrate as an electron accepter were added into growth media. The enriched culture was identified by 16S rRNA gene sequence analysis for the diversity of microbial species. The effect of electron donors (i.e., glucose, acetate, lactate, formate, pyruvate) and electron acceptors (i.e., akaganeite, manganese oxide) on microbial iron/manganese reduction and biomineralization were examined using the 1st enriched culture, respectively. SEM, EDX, and XRD analyses were used to determine morphological features, chemical composition of microbes and mineralogical characteristics of the iron and manganese minerals. Based on 16S rRNA gene analysis, the four species, Fusibacter, Desulfuromonas, Actinobacteria, Pseudomonas sp., from KURT groundwater were identified as anaerobic metal reducers and these microbes precipitated metals outside of cells in common. XRD and EDX analyses showed that Fe(III)-containing mineral, akaganeite (${\beta}$-FeOOH), reduced into Fe(II)/Fe(III)-containing magnetite ($Fe_3O_4$) and Mn(IV)-containing manganese oxide (${\lambda}-MnO_2$) into Mn(II)-containing rhodochrosite ($MnCO_3$) by the microbes. These results implicate that microbial metabolism and respiratory activities under anaerobic condition result in reduction and biomineralization of iron and manganese minerals. Therefore, the microbes cultivated from groundwater in KURT might play a major role to reduce various metals from highly toxic, mobile to less toxic, immobile.

Double Bundle Posterior Cruciate Ligament Reconstruction by the Tibial Inlay Method - Technical note - (경골 내재술식을 이용한 이중 다발 후방 십자 인대 재건술 - 수술 기법 -)

  • Lee, Yeong-Hyun;Nam, Il-Hyun;Moon, Gi-Hyuk;Ahn, Gil-Yeong;Lee, Sang-Chung
    • Journal of the Korean Arthroscopy Society
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    • v.12 no.2
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    • pp.139-146
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    • 2008
  • Purpose: The purpose of this study is to introduce the double bundle posterior cruciate ligament(PCL) reconstruction using Achilles allograft by the tibial inlay method and evaluate the clinical results of 11 cases who had PCL reconstruction using this method and were followed for more than 2 years after surgery. Materials and Methods: Our series consists of 11 cases of PCL reconstruction due to chronic posterior instability of knee and acute PCL rupture. The clinical results were assessed using the IKDC(International Knee Documentation Committee) scoring system, posterior stress radiographs and the maximum posterior displacement using a KT-1000TM arthrometer. Results: The average preoperative posterior displacement in 90 degree flexion stress radiograph was measured 13.4 mm and in 10 degree flexion the average posterior displacement using the KT-1000TM arthrometer was measured 11.4 mm. Postoperatively the 13.4 mm reduced to 4.4 mm and the 11.4 mm reduced to 3.9 mm. According to IKDC scoring system, 9 cases(81.8%) were satisfied. One case showed limitation of flexion with mild stiffness in the knee and another one case was not improved the posterior instability sufficiently and no complication of allograft was noticed. Conclusion: The double bundle PCL reconstruction using Achilles allograft by the tibial inlay method is a useful method for acute PCL rupture and chronic posterior instability of the knee including failed PCL reconstruction, because it will also make the posterior stability in the extension and 90 degree flexion position, and avoid the grafted tendon abrasion by acute turn of tibial tunnel.

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Vibration and Noise Level on the Training Ship Pusan 403 (실습선 부산 403호의 진동과 소음)

  • Park, Jung Hee
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.23 no.2
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    • pp.8-8
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    • 1987
  • This paper describes on the distribution of the vibration and the noise produced on a skipjack pole and line training ship M/S Pusan 403 (243GT, 1,000ps) under the cruising or drifting condition. The vibration and the noise level were measured by use of protable vibration analyzer (B and K 3513) and sound level meter (B and K 2205), and so the vibration level was converted into dB unit. The check points were set through every decks and around important places of the ship. The results obtained can be summarized as follows: 1. The vibration and the noise level 1) On the main deck, both the vibration and the noise level were highest at the vertically above the main engine, whereas the vibration level was the lowest in the bow store and the noise level beneath the bridge. 2) Under cruising condition, the vibration level around the cylinder head of main engine, port side of the engine room, on the shaft tunnel was 80, 67, 65 dB and the noise level 104, 87, 86 dB, respectively. 3) The vibration level on the vertical line passing through the bridge was the highest at the orlop deck with 60 dB and the lowest on the bridge deck with 55 dB, whereas the noise level the highest at the compass deck with 75 dB and the lowest at the orlop deck with 53 dB. 4) The vibration and the noise level on the open decks were the highest with 65 dB and 84 dB on the boat deck, whereas the vibration level was the lowest at the lecture room with 51 dB and the noise level the lowest at the fore castle deck with 57 dB. 5) On the orlop decks, both the vibration and the noise level were the highest at the engine room with 65 dB and 85 dB, and the lowest at bow store with 54 dB and 52 dB, respectively. Comparing with the vibration level and the noise level, the vibration level was higher than the noise level in the bow part and it was contrary in the stern part of the ship. 2. Vibration analysis 1) The vibration displacement and the vibration velocity were the greatest at the cylinder head of main engine with 100μm and 11mm/sec, and were the smallest at the compass deck with 3μm and 0.07mm/sec. They were also attenuated rapidly around the frequency of 100Hz and over. 2) The vibration acceleration was the greatest at the cylinder head with the main frequency of 1KHz and the acceleration of 1.1mm/sec super(2), and the smallest at the compass deck with 30KHz and 0.05mm/sec super(2).

Vibration and Noise Level on the Training Ship Pusan 403 (실습선 부산 403호의 진동과 소음)

  • 박중희
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.23 no.2
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    • pp.54-60
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    • 1987
  • This paper describes on the distribution of the vibration and the noise produced on a skipjack pole and line training ship M/S Pusan 403 (243GT, 1,000ps) under the cruising or drifting condition. The vibration and the noise level were measured by use of protable vibration analyzer (B and K 3513) and sound level meter (B and K 2205), and so the vibration level was converted into dB unit. The check points were set through every decks and around important places of the ship. The results obtained can be summarized as follows: 1. The vibration and the noise level 1) On the main deck, both the vibration and the noise level were highest at the vertically above the main engine, whereas the vibration level was the lowest in the bow store and the noise level beneath the bridge. 2) Under cruising condition, the vibration level around the cylinder head of main engine, port side of the engine room, on the shaft tunnel was 80, 67, 65 dB and the noise level 104, 87, 86 dB, respectively. 3) The vibration level on the vertical line passing through the bridge was the highest at the orlop deck with 60 dB and the lowest on the bridge deck with 55 dB, whereas the noise level the highest at the compass deck with 75 dB and the lowest at the orlop deck with 53 dB. 4) The vibration and the noise level on the open decks were the highest with 65 dB and 84 dB on the boat deck, whereas the vibration level was the lowest at the lecture room with 51 dB and the noise level the lowest at the fore castle deck with 57 dB. 5) On the orlop decks, both the vibration and the noise level were the highest at the engine room with 65 dB and 85 dB, and the lowest at bow store with 54 dB and 52 dB, respectively. Comparing with the vibration level and the noise level, the vibration level was higher than the noise level in the bow part and it was contrary in the stern part of the ship. 2. Vibration analysis 1) The vibration displacement and the vibration velocity were the greatest at the cylinder head of main engine with 100$\mu$m and 11mm/sec, and were the smallest at the compass deck with 3$\mu$m and 0.07mm/sec. They were also attenuated rapidly around the frequency of 100Hz and over. 2) The vibration acceleration was the greatest at the cylinder head with the main frequency of 1KHz and the acceleration of 1.1mm/sec super(2), and the smallest at the compass deck with 30KHz and 0.05mm/sec super(2).

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Mushroom Production Technology with Crop Residues (농산부산물(農産副産物)을 이용(利用)한 식용(食用)버섯 재배(栽培))

  • Cha, Dong-Yeul;Park, Jeong-Sik
    • Applied Biological Chemistry
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    • v.27
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    • pp.47-55
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    • 1984
  • The results of series studies on the ratio of supplements, out-door composting and out-door fermentation induced by using the rice straw as a main substrates at the cultivation of Agaricus bisporus, and the cultivation of Pleurotus ostreatus using the rice straw bundles on its compost are as follows; When rice straw for cultivation of A. bisporus was used as the main substrates in synthetic compost as a carbon source, yields were remarkably high. Fermentation was more rapid than that of barley straw or wheat straw and the total nitrogen content was high in rice straw compost. Use of barley straw compost for cultivation of A. bisporus was shown of low yield compared with rice straw, but when a 50% barley straw and 50% rice straw mixture was used, the yield was almost the same as that using only rice straw. The total organic nitrogen on the compost were shown the positive relation to the yield of A. bisporus, but the ammonium nitrogen negative relation to the mycelial growth and yield of A. bisporus. When rice straw was used as the main substrate for compost media, urea was the most suitable source of nitrogen. Poor results were obtained with calcium cyanamide and ammonium sulfate. When urea was applied three separate times, nitrogen loss during composting was decreased and the total nitrogen content of compost was increased. The supplementation of organic nutrient activated compost fermentation and increased yield of A. bisporus. The best sources of organic nutrients selected were as follows: perilla meal, sesame meal, wheat bran and poultry manure, etc. Soybean meal, tobacco powder and glutamic acid fermentation byproducts which were industrial wastes, could be substituted for perilla meal, sesame meal and wheat bran as organic nutrient sources for compost media. During out door composing of rice straw for cultivation of A. bisporus, using of tuner, composter and tunnel system increased up to 13% of its yield, and also cut down 34% of production Cost. The cultivation of P. ostreatus and utilizing of rice straw and wheat straw was established and its yield was high on the rice straw pots. When the substrates 'Rice straw' was heated by steam at $60^{\circ}C$ for 6 hr. mycelial growth of P. ostreatus was moderately rapid and its yield was high.

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Field research of cultivation technique for stable production of common mushroom(Agaricus bisporus) (양송이 안정생산을 위한 생산기술 현장연구)

  • Jhune, Chang-Sung;Jang, Kab-Yeul;Jeong, Jong-Cheon;Lee, Chan-Jung;Kong, Won-Sik;Yoo, Young-Bok
    • Journal of Mushroom
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    • v.8 no.3
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    • pp.122-130
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    • 2010
  • Common mushroom production per area has been decreased and are up to less than 50% of the 1980 production. To determine the main reasons for the decrement, we performed this study. Two main reasons, which are mushroom disease and the low compost quality because of mechanized compost making, were assessed. In mechanized mushroom farms, nitrogen concentration in compost was lower than recommended and total compost quantity was about 100-150 $kg/3.3m^2$, which was also lower than usual. Our study revealed that higher nitrogen concentration (about 1.5%) in compost gave better production. Also, use of large amount of compost appeared to increase the mushroom production, although more insects and disease problems were observed. The relationships between the presences of microorganisms and occurrence of diseases were assessed by monitoring the microorganism densities near the mushroom farms. Higher number of microorganisms were observed near the mushroom farm area, compared to control region, Daechon beach. Most contaminating molds were found in the circulating fans, tunnel and culture room floor. The bacterial isolates were collected from the air in mushroom culture room and killed with 0.005% Benzalkonium solution, indicating treatment of Benzalkonium are the effective methods to sanitize the mushroom culture room.

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Effects of Soil Aggregate Stability and Wettability on Infiltration and Evaporation (토양입단(土壤粒團)의 안정성(安定性)과 친수성(親水性)이 수분침투(水分浸透) 및 증발(蒸發)에 미치는 영향(影響))

  • Jo, In-Sang;Cho, Seong-Jin;Verplanke, H.;Hartmann, R.;De Boodt, M.
    • Korean Journal of Soil Science and Fertilizer
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    • v.18 no.2
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    • pp.121-127
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    • 1985
  • This study was designed to gain practical data on the use of soil conditioners for more efficient water managements and to establish the optimum levels of structural properties for soil conditioning. A sandy loam and a silt loam soil were each treated with two different soil conditioners, hydrophobic Bitumen or hydrophilic Uresol. The perspex tube 34 cm long were packed homogeneously with air dried soil up to 2 cm below the top, then covered over 2 cm of treated or untreated aggregates. The infiltration rate into the soil columns was measured under simulated rainfall condition. The evaporation study was carried out in the wind tunnel, and the changes of soil moisture distribution of the columns following and during the evaporation were determined by a gamma ray scanner. The infiltration rate of water into the soil column was increased to 18.7-50.8% by the Uresol treatment but it was decreased to less than 25% of control by the Bitumen treatment. Evaporation was decreased to 22.0-68.1% by the Bitumen treatment and to 38.7-68.4% by the Uresol treatment. The water use efficiency of Uresol treated column was increased to more than twice as much as that of untreated soil. Aggregate stability and wetting angle were related to water infiltration and evaporation. A positive and highly significant logarismic relationship was found between the infiltration rate and stability index-wetting angle, evaporation rate and instability index-wetting angle. It was considered that the structural stability is more important than wetting angle. This is true because the structural stability is always positively correlated to water saving, however wettability is positively correlated to the infiltration, and negatively correlated to water saving during the evaporation.

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Development and Evaluation of Traffic Conflict Criteria at an intersection (교차로 교통상충기준 개발 및 평가에 관한 연구)

  • 하태준;박형규;박제진;박찬모
    • Journal of Korean Society of Transportation
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    • v.20 no.2
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    • pp.105-115
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    • 2002
  • For many rears, traffic accident statistics are the most direct measure of safety for a signalized intersection. However it takes more than 2 or 3 yearn to collect certain accident data for adequate sample sizes. And the accident data itself is unreliable because of the difference between accident data recorded and accident that is actually occurred. Therefore, it is rather difficult to evaluate safety for a intersection by using accident data. For these reasons, traffic conflict technique(TCT) was developed as a buick and accurate counter-measure of safety for a intersection. However, the collected conflict data is not always reliable because there is absence of clear criteria for conflict. This study developed objective and accurate conflict criteria, which is shown below based on traffic engineering theory. Frist, the rear-end conflict is regarded, when the following vehicle takes evasive maneuver against the first vehicle within a certain distance, according to car-following theory. Second, lane-change conflict is regarded when the following vehicle takes evasive maneuver against first vehicle which is changing its lane within the minimum stopping distance of the following vehicle. Third, cross and opposing-left turn conflicts are regarded when the vehicle which receives green sign takes evasive maneuver against the vehicle which lost its right-of-way crossing a intersection. As a result of correlation analysis between conflict and accident, it is verified that the suggested conflict criteria in this study ave applicable. And it is proven that estimating safety evaluation for a intersection with conflict data is possible, according to the regression analysis preformed between accident and conflict, EPDO accident and conflict. Adopting the conflict criteria suggested in this study would be both quick and accurate method for diagnosing safety and operational deficiencies and for evaluation improvements at intersections. Further research is required to refine the suggested conflict criteria to extend its application. In addition, it is necessary to develope other types of conflict criteria, not included in this study, in later study.

Effects of Knee Position during the Graft Fixation of the Arthroscopic Anterior Cruciate Ligament Reconstruction with Autogenous Hamstring Graft (이식 건 고정 시 슬관절 위치가 자가 슬괵건을 이용한 관절경적 전방 십자 인대 재건술 후 결과에 미치는 영향)

  • Lee, Churl-Woo;Yoo, Jae-Doo;Roh, Kwon-Jae;Park, Seong-Pil
    • Journal of the Korean Arthroscopy Society
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    • v.9 no.2
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    • pp.143-147
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    • 2005
  • Purpose: In case of anterior cruciate ligament (ACL) reconstruction, graft tendon is generally fixed in tibial tunnel with knee extended. When reconstructing ACL using hamstring tendon, the authors aim to find out the effect of knee joint position during graft fixation on postoperative knee joint stability and range of motion. Materials and Methods: Prospective study was done on patients who have undergone ACL reconstruction using hamstring tendon from May 2002 to January 2003 We used Rigifix system (Mitek Product, Johnson and Johnson, USA) and Intrafix system for fixation. Thirty nine patients received ACL reconstruction during this period. Excluding 2 patients lost in the follow-up, 37 patients were analyzed. The mean follow-up period was 14 months $(13{\sim}25months)$. Knee position was decided alternatively without any bias. Clinical evaluation was based on Lachman test, pivot shift test, Lysholm score, IKDC(international knee documentation committee) assessment and side to side KT-1000 maximal manual arthrometer difference. Results: After the last follow-up, average postoperative Lysholm score was 93.1 poins(65-98points). According to IKDC score, 26 cases were normal, 10 cases were nearly normal, 1 case was abnormal and we had no case of severe abnormality. The mean difference from the normal side was 2.5 mm under maximal manual loading KT-1000 arthrometer. According to postoperative Lachman test, 32 cases were normal,2 cases were grade I and 1 case was grade II. There were 34 cases of normal, 2 cases of grade I and 1 case of grade II. When using maximal manual KT-1000 arthrometer side to side difference, the difference from the normal side while fixing the tibia at 20'knee flexion was 2.3 mm and at full extention the difference was 2.7 mm. The range of motion at postoperative 1 year showed 5 degree flexion contracture in 1 case at 20 degrees knee flexion and 10 degrees of flexion limitation was observed in 2 cases at full extension. Conclusion: When ACL reconstruction using autogenous hamstring tendon, anterior laxity showed no difference in its stability between two groups. Tibial side fixation at full extension may be helpful in preventing flexion contracture due to overconstrained graft tendon.

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Determination of Equivalent Hydraulic Conductivity of Rock Mass Using Three-Dimensional Discontinuity Network (삼차원 불연속면 연결망을 이용한 암반의 등가수리전도도 결정에 대한 연구)

  • 방상혁;전석원;최종근
    • Tunnel and Underground Space
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    • v.13 no.1
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    • pp.52-63
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    • 2003
  • Discontinuities such as faults, fractures and joints in rock mass play the dominant role in the mechanical and hydraulic properties of the rock mass. The key factors that influence on the flow of groundwater are hydraulic and geometric characteristics of discontinuities and their connectivity. In this study, a program that analyzes groundwater flow in the 3D discontinuity network was developed on the assumption that the discontinuity characteristics such as density, trace length, orientation and aperture have particular distribution functions. This program generates discontinuities in a three-dimensional space and analyzes their connectivity and groundwater flow. Due to the limited computing capacity In this study, REV was not exactly determined, but it was inferred to be greater than 25$\times$25$\times$25 ㎥. By calculating the extent of aperture that influences on the groundwater flow, it was found that the discontinuities with the aperture smaller than 30% of the mean aperture had little influence on the groundwater flow. In addition, there was little difference in the equivalent hydraulic conductivity for the the two cases when considering and not considering the boundary effect. It was because the groundwater flow was mostly influenced by the discontinuities with large aperture. Among the parameters considered in this study, the length, aperture, and orientation of discontinuities had the greatest influence on the equivalent hydraulic conductivity of rock mass in their order. In case of existence of a fault in rock mass, elements of the equivalent hydraulic conductivity tensor parallel to the fault fairly increased in their magnitude but those perpendicular to the fault were increased in a very small amount at the first stage and then converged.