본 연구는 영산강수계 수질 특성을 파악하기 위하여 2001~2010년까지 영산강 본류 10개 지점의 수질측정자 료를 활용하여 총 18개 수질항목에 대하여 다변량분석법 을 이용하여 수질항목간의 상관관계 및 요인분석, 군집분 석을 수행하였다. 수질항목간 상관성은 BOD는 T-N, T-P 와 높은 양의 상관성을, Chl-a는 COD와 유의한 양의 상 관성을 보였다. 요인분석 결과 제1요인이 영양염류요인 (32.021%), 제2요인이 유기물 및 조류증식에 따른 물질대 사 요인(17.453%), 제3요인이 계절적 변동요인(14.775%), 제4요인이 미생물요인(10.951%)으로 추출되었다. 요인분 석 결과로부터 추출된 제1요인과 제2요인에 대한 군집 분석 결과, 오염도가 낮은 그룹, 광주천 및 하수처리수 방 류의 영향이 큰 오염도가 높은 그룹, 축산농가 및 농경지 등이 인근에 분포하는 그룹 등 3 그룹으로 분류되었다.
The neurotrophin plays an important role in the development, differentiation and survival of the nervous system in vertebrates. It exerts its cellular effects through two different receptors, the Trk receptor tyrosine kinase neurotrophin receptor and the p75 neurotrophin receptor, a member of the tumor necrosis factor receptor superfamily. Trk and p75 neurotrophin receptors utilize specific target proteins to transmit signals into the cell. An ankyrin-rich membrane spanning protein (ARMS) was identified as a new p75 interacting protein and serves as a novel downstream target of p75 neurotrophin receptor. We sought to delineate the interaction between p75 and ARMS by deletion constructs of p75 and green fluorescent protein (GFP)-tagged ARMS. We examined the interaction between these two proteins after overexpressing them in HEK-293 cells. Using both Western blot analysis and immunocytochemistry followed by confocal laser scanning microscopy, we found out that the intracellular domain of the p75 neurotrophin receptor was important for the interaction with ARMS. The results from this study suggest that ARMS may play an important role for mediating the signals from p75 neurotrophin receptor into the cell.
The dewaterability of pig manure by heat pre-treatment was evaluated in this study. The specific resistance coefficient, a dewatering characteristic, was measured by time to filtration (TTF) test. The experimental conditions were set for heat treatment: 15, 30, 60, and 120 min at 120 ± 1oC and 16, 30, and 60 min at 135 ± 1oC, respectively. The specific resistance coefficient of pig manure was found to be 9.204 × 1011m/kg before treatment, and it gradually decreased with high temperature and long treatment time. Moisture content was decreased from 88% to 77% by heat pre-treatment, and its efficiency was better than mechanical solid-liquid separation with chemical addition. In addition to increased dewaterability, TOC (Total Organic Carbon) concentration was decreased for about 15-42%. Nitrogen concentration was also decreased due to conversion of NH4 +-N to NH3 gas by increased treatment temperature. Consequently, heat pre-treatment was effective for decreasing moisture content and organic matters, and it could have potential for nitrogen recovery.
Asbestos contaminated soil remediation was performed depending on wind velocity and water content using a wind remediation treatment device. The soil samples were collected from upland and paddy soil near inactive asbestos mine and 8% wollastonite was applied instead of asbestos due to health hazard. The wollastonite in soil was analyzed by scanning electron microscopy (SEM) combined with energy dispersive spectrometer (EDS). With 8 m/s of wind velocity, 86% and 92.8% of wollastonite in upland soil and paddy soil were releasable, respectively. When distance from air blast module in the device was 1 ~ 1.5 m, the removal efficiency was highly significant. The removal efficiency decreased as increased as the distance. The releasable wollastonite was significantly affected by water content rather than wind velocity, and this tendency was pronounced with paddy soil. With 0% water content, the correlation between distance and residual amount of wollastonite was low, while the removal efficiency of wollastonite was the highest. Consequently, the removal efficiency of wollastonite was increased with high wind velocity and low water content. For the effective asbestos contaminated soil remediation based on this study, controlling equipment for wind velocity and water content requires in pilot-scale plant and additionally enough air injection and sufficient volume of dust collection module are necessary.
The effects of NaCl concentration on bio-hydrogen production and microbial community by dark-fermentation were evaluated. The examined NaCl concentration was varied from 0 to 5%. When NaCl concentration ranged from 0 to 3%, the hydrogen production was insignificantly affected. 4% or more NaCl concentration decreased accumulated hydrogen production and the lag time was longer. In addition, the metabolite pathway of the bacteria were shifted from butyrate to acetate by microbial community changes with high concentration of NaCl. FISH analysis was achieved to analyze the microbial community after the dark-fermentation performance. Hydrogen producing bacteria, Clostridium sp. Cluster I and Cluster XI, was dominated with 0 ~ 3% of NaCl, while Eubacteria, general bacteria, was dominated with 4 ~ 5% of NaCl. Therefore, the growth and hydrogen production of the hydrogen producing bacteria were inhibited with over 4% of NaCl.
The most effective chemical pretreatment method for Scenedesmus dimorphus was evaluated based on solubilization rate and saccharification yield. When 1% of S. dimorphus with 0.5 N of chemicals such as HCl, H2SO4, HNO3, NaOH and KOH was autoclaved at 120oC and 1.1 atm for 60 min, the solubilization rate was high with alkali chemicals while the saccharification yield was low compared to that with acid chemicals. The pretreatment efficiency was significant in order in HNO3, HCl and H2SO4, however, HCl would be effective for field application considering the cost. The proper concentration and time to treat with HCl were concluded in 1 N and 10 min. In the conditions with 1 : 1 mixed acid chemicals such as H2SO4+ HNO3, HCl + HNO3 and HCl + H2SO4, the solubilization rate was similar to that with single acid treatment, while the saccharification yield was enhanced about 34% in the mixed condition with H2SO4 and HNO3 compared to that treated with H2SO4.