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Field Studios of In-situ Aerobic Cometabolism of Chlorinated Aliphatic Hydrocarbons

  • Semprini, Lewts
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2004.04a
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    • pp.3-4
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    • 2004
  • Results will be presented from two field studies that evaluated the in-situ treatment of chlorinated aliphatic hydrocarbons (CAHs) using aerobic cometabolism. In the first study, a cometabolic air sparging (CAS) demonstration was conducted at McClellan Air Force Base (AFB), California, to treat chlorinated aliphatic hydrocarbons (CAHs) in groundwater using propane as the cometabolic substrate. A propane-biostimulated zone was sparged with a propane/air mixture and a control zone was sparged with air alone. Propane-utilizers were effectively stimulated in the saturated zone with repeated intermediate sparging of propane and air. Propane delivery, however, was not uniform, with propane mainly observed in down-gradient observation wells. Trichloroethene (TCE), cis-1, 2-dichloroethene (c-DCE), and dissolved oxygen (DO) concentration levels decreased in proportion with propane usage, with c-DCE decreasing more rapidly than TCE. The more rapid removal of c-DCE indicated biotransformation and not just physical removal by stripping. Propane utilization rates and rates of CAH removal slowed after three to four months of repeated propane additions, which coincided with tile depletion of nitrogen (as nitrate). Ammonia was then added to the propane/air mixture as a nitrogen source. After a six-month period between propane additions, rapid propane-utilization was observed. Nitrate was present due to groundwater flow into the treatment zone and/or by the oxidation of tile previously injected ammonia. In the propane-stimulated zone, c-DCE concentrations decreased below tile detection limit (1 $\mu$g/L), and TCE concentrations ranged from less than 5 $\mu$g/L to 30 $\mu$g/L, representing removals of 90 to 97%. In the air sparged control zone, TCE was removed at only two monitoring locations nearest the sparge-well, to concentrations of 15 $\mu$g/L and 60 $\mu$g/L. The responses indicate that stripping as well as biological treatment were responsible for the removal of contaminants in the biostimulated zone, with biostimulation enhancing removals to lower contaminant levels. As part of that study bacterial population shifts that occurred in the groundwater during CAS and air sparging control were evaluated by length heterogeneity polymerase chain reaction (LH-PCR) fragment analysis. The results showed that an organism(5) that had a fragment size of 385 base pairs (385 bp) was positively correlated with propane removal rates. The 385 bp fragment consisted of up to 83% of the total fragments in the analysis when propane removal rates peaked. A 16S rRNA clone library made from the bacteria sampled in propane sparged groundwater included clones of a TM7 division bacterium that had a 385bp LH-PCR fragment; no other bacterial species with this fragment size were detected. Both propane removal rates and the 385bp LH-PCR fragment decreased as nitrate levels in the groundwater decreased. In the second study the potential for bioaugmentation of a butane culture was evaluated in a series of field tests conducted at the Moffett Field Air Station in California. A butane-utilizing mixed culture that was effective in transforming 1, 1-dichloroethene (1, 1-DCE), 1, 1, 1-trichloroethane (1, 1, 1-TCA), and 1, 1-dichloroethane (1, 1-DCA) was added to the saturated zone at the test site. This mixture of contaminants was evaluated since they are often present as together as the result of 1, 1, 1-TCA contamination and the abiotic and biotic transformation of 1, 1, 1-TCA to 1, 1-DCE and 1, 1-DCA. Model simulations were performed prior to the initiation of the field study. The simulations were performed with a transport code that included processes for in-situ cometabolism, including microbial growth and decay, substrate and oxygen utilization, and the cometabolism of dual contaminants (1, 1-DCE and 1, 1, 1-TCA). Based on the results of detailed kinetic studies with the culture, cometabolic transformation kinetics were incorporated that butane mixed-inhibition on 1, 1-DCE and 1, 1, 1-TCA transformation, and competitive inhibition of 1, 1-DCE and 1, 1, 1-TCA on butane utilization. A transformation capacity term was also included in the model formation that results in cell loss due to contaminant transformation. Parameters for the model simulations were determined independently in kinetic studies with the butane-utilizing culture and through batch microcosm tests with groundwater and aquifer solids from the field test zone with the butane-utilizing culture added. In microcosm tests, the model simulated well the repetitive utilization of butane and cometabolism of 1.1, 1-TCA and 1, 1-DCE, as well as the transformation of 1, 1-DCE as it was repeatedly transformed at increased aqueous concentrations. Model simulations were then performed under the transport conditions of the field test to explore the effects of the bioaugmentation dose and the response of the system to tile biostimulation with alternating pulses of dissolved butane and oxygen in the presence of 1, 1-DCE (50 $\mu$g/L) and 1, 1, 1-TCA (250 $\mu$g/L). A uniform aquifer bioaugmentation dose of 0.5 mg/L of cells resulted in complete utilization of the butane 2-meters downgradient of the injection well within 200-hrs of bioaugmentation and butane addition. 1, 1-DCE was much more rapidly transformed than 1, 1, 1-TCA, and efficient 1, 1, 1-TCA removal occurred only after 1, 1-DCE and butane were decreased in concentration. The simulations demonstrated the strong inhibition of both 1, 1-DCE and butane on 1, 1, 1-TCA transformation, and the more rapid 1, 1-DCE transformation kinetics. Results of tile field demonstration indicated that bioaugmentation was successfully implemented; however it was difficult to maintain effective treatment for long periods of time (50 days or more). The demonstration showed that the bioaugmented experimental leg effectively transformed 1, 1-DCE and 1, 1-DCA, and was somewhat effective in transforming 1, 1, 1-TCA. The indigenous experimental leg treated in the same way as the bioaugmented leg was much less effective in treating the contaminant mixture. The best operating performance was achieved in the bioaugmented leg with about over 90%, 80%, 60 % removal for 1, 1-DCE, 1, 1-DCA, and 1, 1, 1-TCA, respectively. Molecular methods were used to track and enumerate the bioaugmented culture in the test zone. Real Time PCR analysis was used to on enumerate the bioaugmented culture. The results show higher numbers of the bioaugmented microorganisms were present in the treatment zone groundwater when the contaminants were being effective transformed. A decrease in these numbers was associated with a reduction in treatment performance. The results of the field tests indicated that although bioaugmentation can be successfully implemented, competition for the growth substrate (butane) by the indigenous microorganisms likely lead to the decrease in long-term performance.

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Management Guidelines on the Large Old Trees as the Natural Monuments in Seoul, Incheon, and Gyeonggi Province through the Analysis of the Growing Environment (생육환경 분석을 통한 서울·인천·경기지역 천연기념물 노거수의 관리방안)

  • Lee, Seung Je
    • Korean Journal of Heritage: History & Science
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    • v.42 no.1
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    • pp.88-99
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    • 2009
  • This study was conducted to formulate management guidelines for Natural monumental old trees in Korea through survey of tree vigor and analysis of growing environments. A total of 20 old trees designated as natural monuments in Seoul, Incheon, and Gyeonggi Province were surveyed. The biological characteristics were surveyed with 4 items of species, ages and height of trees. The surrounding environments were surveyed with 2 items of location types and surroundings. The root conditions were surveyed with 2 items of denudation and molding depth. The health conditions were surveyed with 5 items of withering rate, cavity size, bark breakaway rate, damages by blight and insects, and growing tips. The soil conditions were surveyed with 6 items of PH, organic contents, valid phosphoric acid, transposal cations(K, Ca) and soil compaction. On the basis of outcomes of these research items, mutual relations among locations, growings and soil conditions of old trees were analyzed by carring out cross tabulation, correlation, and simple and multiple regression. Management guidelines were presented searching the factors effecting on the health of the monumental old trees. On the biological characteristics, the old trees designated as natural monuments were Pinus bungeana(4 trees), Juniperus chinensis(3 trees), Ginkgo biloba(3 trees), Poncirus trifoliata(2 trees). Actinidia arguta, Wisteria floribunda, Thuja orientalis, Quercus mongolica, Sophora japonica, Fraxinus rhynchophylla, Zelkova serrata, and Pinus densiflora. The tree height ranged from 4.2 to 39.2m, and root collar rounds ranged from 1.01 to 15.2m. On the surrounding environments, The location types ; Gardens(4), historical sites(5), residental sections(3) open agricultural fields(3), mountain hills(3), and near ocean beaches(1) and stream site(1). The surroundings ; 75% denudation of roots, molded more than 10cm except 4 trees(25%). On the health conditions, 1)Withering rate ; Ginkgo biloba(20%) in Yongmoon temple, (5%) in Saki-ri, kanwha-gun, and others had no withering rate. 2) Cavity size ; all subject had $5{\sim}100cm^3$ of cavity. 3) Bark breakaway rate ; Pinus bungeana in Soosong-dong, in the shrine of Confucius, in Samchung-dong, especially high rate of cavity(5~50%) in Seoul area and in Saki-ri, Kangwha-gun were high 45% brakeaway rate. 4) Damages by blight and insects was slight due to managements. 5Growing tips ; In cases of Juniperus chinensis in Changdeok palace and SunnogDang, seoul, growing tips were 1/2, presumably cause by air pollution, and in cases of Fraxinus rhynchophylla in Paju city and Pinus densiflora in BacksaDorip-ri, Icheon city, growing tips were fine, presumably because there were no moldings. On the Soil conditions, Soil pH ranged from 5.2 to 8.3, organic matter contents from 12% to 56%, phosphorus contents from 104 to 618ppm, soil compaction ranged from 7 to 28mm( among them, Denudation was severe with 21~28mm soil compactions in cases of Pinus bungeana in Soosong -dong, Thuja orientalis in Samchung -dong, Ginkgo biloba in the shrine of Confucius and in Yongmoon temple.) Results of cross tabulation, correlation, and regression analysis showed that molding depth was the most serious factor to deteriorate the tree vigor and cambium conductivity. In addition, soil acidity, organic matter contents, disease and insect damages and cambial detachment were also related to the tree vigor. Additional research of these relationships will be needed to conduct more detailed studies. Based on the relationships between the tree vigor and growing environments, it is considered that old trees should be managed to give them more growing spaces and less abuses. Also, molded soils should be removed and further soil-molding around the tree collar should be prohibited. For the construction of systematic management and removal of harmful factors, appropriative management according to spices, persistent monitering of damaged cases and construction of management system through the accumulation of data on the relationships of soil conditions are required.

Development and Validation of an Analytical Method for Fungicide Fluoxastrobin Determination in Agricultural Products (농산물 중 살균제 Fluoxastrobin의 시험법 개발 및 유효성 검증)

  • So Eun, Lee;Su Jung, Lee;Sun Young, Gu;Chae Young, Park;Hye-Sun, Shin;Sung Eun, Kang;Jung Mi, Lee;Yun Mi, Chung;Gui Hyun, Jang;Guiim, Moon
    • Journal of Food Hygiene and Safety
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    • v.37 no.6
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    • pp.373-384
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    • 2022
  • Fluoxastrobin a fungicide developed from Strobilurus species mushroom extracts, can be used as an effective pesticide to control fungal diseases. In this study, we optimized the extraction and purification of fluoxastrobin according to its physical and chemical properties using the QuEChERS method and developed an LC-MS/MS-based analysis method. For extraction, we used acetonitrile as the extraction solvent, along with MgSO4 and PSA. The limit of quantitation of fluoxastrobin was 0.01 mg/kg. We used 0.01, 0.1, and 0.5 mg/kg of five representative agricultural products and treated them with fluoxastrobin. The coefficients of determination (R2) of fluoxastrobin and fluoxastrobin Z isomer were > 0.998. The average recovery rates of fluoxastrobin (n=5) and fluoxastrobin Z isomer were 75.5-100.3% and 75.0-103.9%, respectively. The relative standard deviations (RSDs) were < 5.5% and < 4.3% for fluoxastrobin and fluoxastrobin Z isomer, respectively. We also performed an interlaboratory validation at Gwangju Regional Food and Drug Administration and compared the recovery rates and RSDs obtained for fluoxastrobin and fluoxastrobin Z isomer at the external lab with our results to validate our analysis method. In the external lab, the average recovery rates and RSDs of fluoxastrobin and fluoxastrobin Z isomer at each concentration were 79.5-100.5% and 78.8-104.7% and < 18.1% and < 10.2%, respectively. In all treatment groups, the concentrations were less than those described by the 'Codex Alimentarius Commission' and the 'Standard procedure for preparing test methods for food, etc.'. Therefore, fluoxastrobin is safe for use as a pesticide.

Antioxidant activity of partially purified extracts isolated from Acanthopanax sessiliflorum Seeman (오가피 분획 추출물의 항산화효과)

  • Im, Kyung-Ran;Kim, Mi-Jin;Jung, Teak-Kyu;Yoon, Kyung-Sup
    • KSBB Journal
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    • v.23 no.4
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    • pp.329-334
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    • 2008
  • The antioxidant activity and the qualitative analysis of Acanthopanax sessiliflorum Seeman were studied by partially purified extract using various methods: extraction by using ethanol solutions and temperatures, and absorption to Diaion HP20 column chromatography using 10%, 20%, 40%, 60% ethanol solutions. Major constituents, chlorogenic acid, caffeic acid, eleutheroside E, was determinated by HPLC method in Acanthopanax sessiliflorum S. 10% and 20% ethanol solutions contain chlorogenic acid (3.020$\pm$0.080%, 20.500$\pm$1.150%, respectively). 40% ethanol solution contains caffeic acid and eleutheroside E (12.270$\pm$0.360%, 1.670$\pm$0.140%, respectively). Diaion HP20 fractions (10%, 20%, 40%, 60% ethanol solutions) showed the scavenging activity of radicals and reactive oxygen species with the $IC_{50}$ values of $81.534{\pm}0.992{\mu}g/ml$, $1.748{\pm}0.098{\mu}g/ml$, $11.487{\pm}1.768{\mu}g/ml$, $21.960{\pm}0.547{\mu}g/ml$ against 1,1-diphenyl-2-picrylhydrazly radical and $1713.548{\pm}34.565{\mu}g/ml$, $131.419{\pm}2.235{\mu}g/ml$, $200.681{\pm}2.444{\mu}g/ml$, $757.897{\pm}6.868{\mu}g/ml$ against superoxide radicals in the xanthine/xanthine oxidase system, respectively. Especially, 20% and 40% ethanol fractions showed more antioxidant activity than dl-$\alpha$-tocopherol. These results suggest that Acanthopanax sessiliflorum S. extract and Diaion HP20 fractions may be useful as a potential source of nutraceutical and cosmetic products.

Reproductive Ecology of the Bladder Moon, Glossaulax didyma (Gastropoda: Naticidae) in Western Korea (한국 서해산 큰구슬우렁이, Glossaulax didyma (복족강: 구슬우렁이과) 의 번식생태)

  • Kim, Dae-Gi;Chung, Ee-Young;Shin, Moon-Seup;Hwang, Kyu
    • The Korean Journal of Malacology
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    • v.23 no.2
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    • pp.189-198
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    • 2007
  • The reproductive cycle, egg capsules in the egg-mass, first sexual maturity, and sex ratio of the bladder moon, Glossaulax didyma ($R\ddot{o}ding$) were investigated. The gastropods collected from the intertidal zone of Biin Bay, Seocheon, Korea were studied by using histological analysis and morphometric data. The gonadosomatic index (GSI) of females and males began to increase in March and reached maximum in May. Then their values sharply decreased from late in May to August due to spawning. The condition index (CI) began to increase in February and reached maximum in May, then gradually declined in the spawning period. The CI calculated for determination of the spawning period was coincided with changes in the GSI and gonadal phases. Spawning occurred between late in May to August in females and early in May to August in males. Spawning peak was observed between July and August when the seawater temperature rose to 19 $^{\circ}C$. Reproductive cycle with the gonadal development phases of this species can be divided into five successive stages in females and four in males: in females, early active stage (December to February), late active stage (February to March), ripe stage (April recovery stage (August to November); in males, active stage (December to March), ripe stage (March to July), copulation stage (early May to August), and recovery stage (August to January). Fully matured oocytes were approximately 250-270 ${\mu}m$ in size. The egg-mass was a hat in shape, and a number of egg capsules were found in an egg-mass. An egg capsule was 0.53-0.57 mm in size. An embryo (veliger larva) hatched from an egg capsule. Percentage of first sexual maturity in females and males were over 50% for individuals that are 40.1-45.0 mm in shell radius, and 100% for those that are over 45.1 mm. The sex ratio of female to male was significantly different from 1:1 $(x^2\;=\;57.22,\;p\;<\;0.05)$.

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Economics and Ground Cover Growth Characteristics of a New Method of Shallow Soil Artificial Foundation Planting (저토심 인공지반 녹화공법의 경제성 및 도입 가능한 지피식물의 생육특성)

  • Choi, Jin-Woo;Kim, Hag-Kee;Lee, Kyong-Jae;Kang, Hyun-Kyung
    • Journal of the Korean Institute of Landscape Architecture
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    • v.37 no.5
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    • pp.98-108
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    • 2009
  • The purpose of this study is to analyze the characteristics of limited methods, economics and breeding appropriateness of native and imported ground cover plants in the methodology of a shallow soil rooftop garden. The new shallow soil rooftop gardening method uses a total of 13cm in soil thickness, including 4.5cm of top soil on a 7.5cm rock-wool-mat stacked onto a 1cm roll-type-draining plate. The total construction cost for each method of soil level within the design price standard for SEDUM BLOCK is 89,433won/$m^2$, and for DAKU is 92,550won/$m^2$. By comparing those two methods, the construction cost of the shallow soil artificial foundation methodology is 45,000won/$m^2$; this shows the new method is 50% less expensive than the existing method of shallow soil rooftop gardening. The experiment was executed on the rooftop of the Korean National Housing Corporation to ensure validity of the shallow soil artificial foundation planting, and the sample plants which were imported and grown now in native covering. A list investigating the growing plants was made of the cover rate in each plant class, both while alive and the dry plant weight. The native ground cover plants, Sedum kamtschaticum, Sedum middendorffianum, Allium senescens, Sedum sarmentosum, Aquilegia buergariana, and Caryopteris incana increased the cover rate, live weight and dry weight in the shallow soil artificial foundation method. Among the imported cover plants, Sedum sprium and Sedum reflexum, the cover rate increased and growth conditions improved. However, some species needed weed maintenance. After examination with the less expensive shallow soil artificial foundation method and growth analysis, it was found that rooftop gardens are a low-cost option and the growth of plants is great. This result shows the new method can contribute to the proliferation of rooftop gardens in urban settings.

Evaluation of Antimicrobial, Antioxidant, and Antithrombin Activities of the Rhizome of Various Dioscorea Species (마 품종별 메탄올 추출물의 항균, 항산화 및 항혈전 활성 평가)

  • Kwon, Jung-Bae;Kim, Mi-Sun;Sohn, Ho-Yong
    • Food Science and Preservation
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    • v.17 no.3
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    • pp.391-397
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    • 2010
  • Yams (Dioscorea spp.) have been used as medicinal and edible resources worldwide. In the present study, methanol extracts were prepared from various kinds of yam, including D. batatas (Gyeongbuk No. 1 and No. 4), D. alata L. (Gyeongbuk No. 5 and No. 6), and D. bulbifera and D. nipponica, and the antioxidant, antithrombin, and antimicrobial activities of these extracts were evaluated. The water content of the various yams was 54.7~83.2% (D. batatas> D. alata L.>D. nipponica>D. bulbifera) and the methanol extracts contained 0.59-1.59% (w/v) solid matter (D. alata L.>D. batatas >D. nipponica>D. bulbifera). The mean concentrations of total polyphenols, total flavonoids, and total sugars in the different types of yam were 49.82 mg/g, 9.79 mg/g, and 173.81 mg/g, respectively. Analysis of DPPH radical-scavenging activity showed that D. alata L. Gyeongbuk No. 6 had a strong antioxidant capacity (IC50=$142.30{\mu}g/mL$), whereas the other yams showed reduced levels of activity (IC50=371-$486{\mu}g/mL$). D. alata L. Gyeongbuk No. 6 showed a strong antithrombin activity against human thrombin. Upon treatment with a D. alata methanol extract (1.5 mg/mL), thrombin time was increased 7.35-fold compared with that when methanol alone was used. In an antimicrobial activity assay, the D. nipponica extract showed moderate antibacterial activity against Bacillus subtilis, Staphylococcus aureus, Proteus vulgaris, and Salmonella typhimurium. Our results indicate that different varieties of Dioscorea spp., including D. batatas, have useful biochemical attributes, including antioxidant, antithrombin, and antibacterial activities.

A Study on the Biotope Structure of Wintering Place and Behavior Characteristics of Anser fabalis in Cheongna Area, Incheon Free Economic Zone, Korea (인천경제자유구역 청라지구에서의 큰기러기 월동지 비오톱구조와 행동특성 연구)

  • Park, Byeong-Ku;Han, Bong-Ho;Lee, Kyong-Jae;Kwak, Jeong-In;Im, Seong-Soo
    • Korean Journal of Environment and Ecology
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    • v.27 no.3
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    • pp.305-315
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    • 2013
  • This study is aimed to provide the preliminary data for conservation and management of wintering site for Anser fabalis population in Cheongna Area, Incheon Free Economic Zone, Korea through analyzing the relationship between the biotop structure of its wintering site and behavior characteristics. The main types (size and ratio) of the biotope in Cheongna Area, Incheon Free Economic Zone are reed wetlands ($6,093,762m^2$, 47.8%), rice fields without rice straw ($2,927,916m^2$, 23.0%), and rice fields with rice straw ($1,915,655m^2$, 15.0%). According to the survey carried on 13th Feb., 2013, total 33 species and 6, 535 individual birds were observed and among of them, the dominant bird was Anser fabalis showing 5,128 indiviuals, 78% of total population. As the result of analyzing the migratory route of Anser fabalis, the bird moved from roosting site to foraging site before and after sunrise and from feeding site to roosting site before and after sunset. According to the analysis of interrelation between habitat characteristics and biotope types of the bird, population density was the highest in reed wetlands among habitat types and individual appearance was the highest in water-filled rice field melting ice. The bird ate the roots and bulb of hydrophytes in reed wetlands and showed various behaviors like eating dropped grains, resting and sleeping in water-filled rice fields and eating dropped grains and resting in rice fields with and without rice straw. It is shown that the number of Anser fabalis appearing in rice fields is depended on the presence of dropped grains than types of rice field.

Quantitative Expression Analysis of Functional Genes in Four Dog Breeds (개의 네 품종에서 기능 유전자들에 대한 정량적 발현 분석)

  • Gim, Jeong-An;Kim, Sang-Hoon;Lee, Hee-Eun;Jeong, Hoim;Nam, Gyu-Hwi;Kim, Min Kyu;Huh, Jae-Won;Choi, Bong-Hwan;Kim, Heui-Soo
    • Journal of Life Science
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    • v.25 no.8
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    • pp.861-869
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    • 2015
  • One of the domesticated species; the dog has been selectively bred for various aims by human. The dog has many breeds, which are artificially selected for specific behaviors and morphologies. Dogs contribute their life to human as working dogs for guide, rescue, detection or etc. Working dogs requires good personality, such as gentleness, robustness and patience for performing their special duty. Many studies have concentrated on finding genetic marker for selecting the high-quality working dog. In this study, we confirmed quantitative expression patterns of eight genes (ABAT; 4-Aminobutyrate Aminotransferase, PLCB1; Phospholipase C, Beta 1, SLC10A4; Solute Carrier Family 10, Member 4, WNT1; Wingless-Type MMTV Integration Site Family, Member 1, BARX2; BarH-Like Homeobox 2, NEUROD6; Neuronal Differentiation 6, SEPT9; Septin 9 and TBR1; T-Box, Brain, 1) among brains tissues from four dog breeds (Beagle, Sapsaree, Shepherd and Jindo), because these genes were expressed and have functions in brain mostly. Specially, BARX2, SEPT9, SLC10A4, TBR1 and WNT1 genes were highly expressed in Beagle and Jindo, and Sapsaree and German Shepherd were vice versa. The biological significance of total genes was estimated by database for annotation, visualization and integrated discovery (DAVID) to determine a different gene ontology (GO) class. In these analyses, we suppose to these eight genes could provide influential information for brain development, and intelligence of organisms. Taken together, these results could provide clues to discover biomarker related to functional traits in brain, and beneficial for selecting superior working dogs.

Effect of Coagulants and Separation Methods on Algal Removal in Water Treatment Process (정수처리에서 응집제 종류와 분리공정이 조류 제거에 미치는 영향)

  • Park, Hung-Suck;Lee, Sang-Yoon
    • Journal of Korean Society of Environmental Engineers
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    • v.22 no.2
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    • pp.279-289
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    • 2000
  • The objective of this study was to investigate the effect of coagulants and solid-liquid separation methods on algal removal in water treatment processes. Thus characterization of raw water quality in terms of turbidity. UV-254, $KMnO_4$ consumption, chlorophyll-a and correlation analysis of these parameters were conducted. In addition, the effect of commercial Al-based coagulants(Alum. PAC and PACS) on algal removal was studied by turbidity and organic removal, algal species removal, characteristic of pH drop and alkalinity consumption using laboratory jar tests. Organic components including UV-254, $KMnO_4$ consumption, chlorophyll-a in case of algal bloom were highly correlated with turbidity and the correlation coefficients of UV-254, $KMnO_4$ consumption, chlorophyll-a with turbidity were 0.775, 0674 and 0.623, respectively. In coagulation and sedimentation, the Al-based coagulants showed similar efficiency of organic and turbidity removal in low organic($KMnO_4$ consumption below 15mg/l) and low turbidity(below 30NTU). However, PAC and PACS showed better algal removal than alum in high organic concentration($KMnO_4$ consumption above 20mg/l) and high turbidity(above 100NTU) raw water conditions generated by high algal growth, which is considered to be due to the floc settleability. In comparison of sedimentation and flotation after chemical coagulation and flocculation, the removal efficiency of organic and turbidity were higher in case of alum dose with flotation than with sedimentation, while those were better in case or PAC and PACS with sedimentation than with flotation. Thus, Alum with flotation and PAC and PACS with sedimentation is recommended for efficient algal removal. The dominant phytoplankton in raw water were Microcystic and pediastrum simplex and the removal efficiency of algae with sedimentation using alum. PAC and PACS were 27%, 45% and 22% respectively, while those with DAF showed 100% removal of phytoplankton and zooplankton.

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