• Title, Summary, Keyword: Sediment cell

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Electricity Production by Metallic and Carbon Anodes Immersed in an Estuarine Sediment (퇴적토에 담지된 금속 및 탄소전극에 의한 전기 생산 특성)

  • Song, Hyung-Jin;Rhee, In-Hyoung;Kwon, Sung-Hyun;Cho, Dae-Chul
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.10 no.12
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    • pp.3731-3739
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    • 2009
  • One-chambered sediment cells with a variety of anodic electrodes were tested for generation of electricity. Material used for anodes was iron, brass, zinc/iron, copper and graphite felt which was used for a common cathode. The estuarine sediment served as supplier of oxidants or electron-producing microbial habitat which evoked electrons via fast metal corrosion reactions or a complicated microbial electron transfer mechanism, respectively. Maximum power density and current density were found to be $6.90\;W/m^2$ (iron/zinc) and $7.76\;A/m^2$ (iron), respectively. Interestingly, copper wrapped with carbon cloth produced better electric performance than copper only, by 60%, possibly because the cloth not only prevented rapid corrosion on the copper surface by some degrees, but also helped growing some electron-emitting microbes on its surface. At anodes oxidation reduction potential(ORP) was kept to be stationary over time except at the very initial period. The pH reduction in the copper and copper/carbon electrodes could be a sign of organic acid production due to a chemical change in the sediment. The simple estimation of interfacial, electrical resistances of electrodes and electrolyte in the sediment cell that a key to the electricity generation should be in how to control corrosion rate or microbial electron transfer activity.

Plant Cells on Earth and in Space

  • Braun, Markus;Sievers, Andreas
    • Animal cells and systems
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    • v.4 no.3
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    • pp.201-214
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    • 2000
  • Two quite different types of plant cells are analysed with regard to transduction of the gravity stimulus: (i) Unicellular rhizoids and protonemata of characean green algae; these are tube-like, tip-growing cells which respond to the direction of gravity. (ii) Columella cells located in the center of the root cap of higher plants; these cells (statocytes) perceive gravity. The two cell types contain heavy particles or organelles (sataoliths) which sediment in the field of gravity, thereby inducing the graviresponse. Both cell types were studied under microgravity conditions ($10^{-4}$/ g) in sounding rockets or spacelabs. From video microscopy of living Chara cells and different experiments with both cell types it was concluded that the position of statoliths depends on the balance of two forces, i.e. the gravitational force and the counteracting force mediated by actin microfilaments. The actomyosin system may be the missing link between the gravity-dependent movement of statoliths and the gravity receptor(s); it may also function as an amplifier.

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The Diagnoses and Surgical Treatment of Transitional Cell Carcinoma in the Urinary Bladder in a Dog (방광에 발생한 이행상피암종의 진단과 수술적 처치)

  • 김성미;장화석;송영성;김혜진;김순신;김휘율
    • Journal of Veterinary Clinics
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    • v.21 no.1
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    • pp.62-65
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    • 2004
  • A 13-year-old, male Maltese was refered to Veterinary Teaching Hospital of Konkuk University with inappropriate urination and hematuria. CBC, serum chemistry profile, urinalysis and urine culture were performed. Malignant cells were found in the urine sediment. Thoracic and abdominal radiography, retrograde positive-contrast cystography, retrograde double-contrast cystography, excretory urography, ultrasonography were performed. On the retrograde positive-contrast cystography examination, irregular filling defects were present on the left side of the cranial part of the bladder. Partial cystectomy performed and then medical therapy was conducted. On histopathological examinations, the lesion was confirmed as a transitional cell carcinoma of the urinary bladder.

Systemic Lupus Erythematosus in a Dog, Suspexted Systemic Lupus Erythematosus in a Dog, and Autoimmune Thrombocytopenic Purpura Hemorrhagica in a Dog (개에 있어서 전신성홍반성루프스 1예와 전신성혼반성루프스 의증 1예 및 자가면역성혈소판감소성출혈성자반병 1예)

  • 이창우;나기정;임정식;서정욱
    • Journal of Veterinary Clinics
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    • v.13 no.1
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    • pp.81-86
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    • 1996
  • Systemic lupus erythematosus in a dog, suspected systemic lupus erythematosus in a dog, and autoimmune thrombocytopenic purpura hemmorrhagica in a dog are reported. A fice-year old, female Chihuahua (Case 1) showed initially hemorrhagic diathesis and purpura hemorrhagica. Afterward, it showed polymyositis and polyarthritis. LE-cell was demonstrated on LE-cell preparation trom blood. Systemic lupus erythematosus was diagnosed. This reponded well to the immunosuppressants, but developed iatrogenic Cushing syndrome and steroid hepatopathy. A two-and-half-year old, male toy poodle (Case 2) had chief complaint of red urine. Occult blood test for the urine sediment. This did not respond at all to antibiotics and carbazochrome, which is one of systemic coagulants. LE-cell was demonstrated on LE-cell preparation from blood. This responded relatively well to immunosupressants such as prenisolone, azathioprine and cyclophosphamide. systemic lupus erythematosus is suspected. A nine-year-and-three-month old, female Maltese (Case 3), which had history of congestive heart failure and ovariohysterectomy showed purpura hemorrhagica in the skin of chest. This had severe thrombocytopenia and leukocytosis. As prednisolone was administered before immunological examination or demonstration of LE-cell, it was impossible to diagnose whether purpura hemorrhagica developed as a member of systemic lupus erythematosus or independent of systemic lupus erythematosus. This responded well to prednisolone, and so autoimmune thrombocytopenic purpura hemorrhagica was diagnosed.

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Studies on the Nuclei Adduction and Expression of c-myc Gene by Benzo(a)pyrene and Doxorubicin in Human NC-37 Cells (사람 NC-37 세포에서 Benzo(a)pyrene과 Doxorubicin에 의한 Nuclei내전과 c-myc 유전자의 발현에 대한 연구)

  • 김호찬;정인철;조무연
    • Journal of Life Science
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    • v.8 no.4
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    • pp.400-409
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    • 1998
  • Formation of adduct was studied in benzo(a)pyrene(BP)- and doxorubicin(Dx)-treated human NC-37 cells and isolated nuclei. Major adducts formed were determined by fluorescence absorption spectrophotometery and DNA-lin-ked protein assay. When isolated nuclei were exposed to carcinogens BP and DMBA, and anticancer drugs m-AMSA, ellipticine and Dx, varying degrees of adduct formation occured between DNA-protein complex and these drugs. When the mixture was centrifuged 1.7 M sucrose solution, binding BP and DMBA appeared to be similar between the sediment and the supernatant. When the sediment was centrifuged again with 0.35% polymin-P, the amount of BP bound was 2-fold greater in the protein(1077$\pm$55cpm) than in DNA fraction (470$\pm$20cpm), whereas that of DMBA was 1.6-fold greater in the DNA than in protein fraction. In the case of m-AMSA, ellipticine and Dx, the amount of binding was slightly greater in supernatant than in sediment in centrifugation with 1.7 M sucrose, and more than 3 times greater in the DNA- than in protein- fraction in centrifugation with 0.35% polymin P. DNA fractions which associated with a subset of nonhistone chromosomal protein were isolated from NC-37 cells exposed to $^{3}$H-BP and $^{14}$C-Dx. They were separated into two distince components DNA-S and DNA-P by centrifugation with 2M Nacl chromatin extraction. The results indicated that the amount of $^{3}$H-BP bound was 6.0-fold greater in DNA-P as compared with DNA-S, while that of $^{14}$C-Dx binding appreaed to be 6.2-fold greater in DNA-S than in DNA-P fraction. When $^{3}$H-BP binding wasdetermined in the presence of cold Dx, the amount of binding was reduced only in the DNA-P fraction, indicating that the interaction between DNA and protein is decreased. Gene expression by these drugs, BP treated cells were increased to compare with nomal cells but reduced by treatment with BP-Dx. These results suggest that the protein moiety which tightly bound to DNA-P fraction may play an important role in the regulation of gene expression.

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Geotechnical properties of gas hydrate bearing sediments (가스 하이드레이트 부존 퇴적토의 지반공학적 물성)

  • Kim, Hak-Sung;Cho, Gye-Chun;Lee, Joo-Young
    • 한국신재생에너지학회:학술대회논문집
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    • pp.151-151
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    • 2011
  • Large amounts of natural gas, mainly methane, in the form of hydrates are stored on continental margins. When gas hydrates are dissociated by any environmental trigger, generation of excess pore pressure due to released free gas may cause sediment deformation and weakening. Hence, damage on offshore structures or submarine landslide can occur by gas hydrate dissociation. Therefore, geotechnical stability of gas hydrate bearing sediments is in need to be securely assessed. However, geotechnical characteristics of gas hydrates bearing sediments including small-strain elastic moduli have been poorly identified. Synthesizing gas hydrate in natural seabed sediment specimen, which is mainly composed of silty-to-clayey soils, has been hardly attempted due to their low permeability. Moreover, it has been known that hydrate loci in pore spaces and heterogeneity of hydrate growth in specimen scale play a critical role in determining physical properties of hydrate bearing sediments. In the presented study, we synthesized gas hydrate containing sediments in an instrumented oedometric cell. Geotechnical and geophysical properties of gas hydrate bearing sediments including compressibility, small-strain elastic moduli, elastic wave, and electrical resistivity are determined by wave-based techniques during loading and unloading processes. Significant changes in volume change, elastic wave, and electrical resistivity have been observed during formation and dissociation of gas hydrate. Experimental results and analyses reveal that geotechnical properties of gas hydrates bearing sediments are highly governed by hydrate saturation, effective stress, void ratio, and soil types as well as morphological feature of hydrate formation in sediments.

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Cytotoxic Polyene Antibiotics from Myxococcus stipitatus JW111 (Myxococcus stipitatus JW111이 생산하는 Polyene계 항암활성물질)

  • Ahn, Jong-Woong
    • Applied Biological Chemistry
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    • v.45 no.2
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    • pp.114-118
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    • 2002
  • Phenalamides $A_1{\sim}A_3$ were reisolated as cytotoxic substances from culture broth of Myxococcus stipitatus JW111. The producing strain was isolated from the marine sediment collected off the shore of Geomun Island, Korea. The active principles were extracted from cell mass with acetone and successively purified by silica gel column chromatography, Sephadex LH-20 column chromatography, and finally recycling prep. HPLC. These compounds demonstrated significant cytotoxicity against certain human cancer cells, having $IC_50$ values ranging from 0.23 to 0.50 ${\mu}g/ml$. Moreover, they also inhibited the growth of adriamycin-resistant HCT/ADM human cancer cell line as well as its parent sensitive cell line.

A Single Cell Multimedia Fate Model for Endocrine Disrupting Chemicals

  • Park, Kyunghee;Junheon Youn;Daeil Kang;Lee, Choong;Lee, Dongsoo;Jaeryoung Oh;Sunghwan Jeon;Jingyun Na
    • Proceedings of the Korea Society of Environmental Toocicology Conference
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    • pp.149-149
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    • 2003
  • To understand environmental paths of the transport and accumulation of endocrine disrupting chemicals (EDCs), a single cell multimedia fate model has been constructed and evaluated. The EDCs of concern were PAHs, Organochlorine Pesticides (OCPs), PCBs, Alkyl phenols, and phthalates. An evaluation model was designed for the multimedia distribution, including air, water, soil, sediment and vegetation. This model was verified using reported values and via monitoring data. Based on collected data, the distribution trends of EDCs with respect to environmental media were analyzed. Those results have applied to the model for the prediction of the spatial and temporal distribution of EDCs in Seoul. Especially, phenol compound, phthalates, PAHs, PCBs and organochlorine pesticides were estimated and the model was verified. This model was successfully conducted to environmental media, such as air (vapor and suspended particles), soils (forest soil, bare soil, and cement-concrete covered soil), water (dissolved and suspended solids), sediment, trees (deciduous and coniferous). The discrepancies between the model prediction and the measured data are approximately within or near a factor of 10 for the PAHs of three rings through that of six rings, implying that multimedia distribution of the PAHs could be predicted with a factor of 10. Concerning about the air equilibrium may be assumed, a fugacity at steady state is similar in all environmental media. Considering the uncertainties of this model, the use of equilibrium models may be sufficient for assessing chemical fates. In this study, a suggestion was made that modeling and estimation of chemicals in environmental multimedia be rigorously evaluated using the measured flux data. In addition, these data should be obtained, for example, from the precise and standardized inventory of the target chemicals. The model (EDC Seoul) will be refined in an on-going research effort and will be used to support decision-making concerning the management of EDCs.

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Antimicrobial Effect of Grapefruit Seed Extract on Vibrio parahaemolyticus Isolated from the Southern Adjacent Sea of Korea (남해안연안에 분포되어 있는 Vibrio Parahaemolyticus의 성상 및 Grapefruit Seed Extract 처리에 의한 향균효과)

  • 조성환;강동훈;전상수;정덕화
    • Journal of Food Hygiene and Safety
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    • v.9 no.3
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    • pp.141-149
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    • 1994
  • To investigate the distribution of Vibrio parahaemopyticus in the southern 4 coastal areas, Vibrio parahaemolyticus was isolated from seawater, shellfish and sediment from May to October in 1991, and antimicrobial effect of grapefruit seed extract (GFSE) on the growth of isolated strains were examined. In the 120 sample from 4 coastal areas, 16 strains of Vibrio parahaemolyticus were isolated and identified. The distribution serotype of isolated strains was 10 types of monovalent k-antiserum. Especially k-5 and k-28 were highly distribyted with 3 and 4 strains. 31.3% of isolated strains showed positive on Kanagawa phenomenon test. All isolated Vibrio parahaemolyticus were sensitive to chloramphenicol and gentamycin, 5 and 6 strains were resistant to streptomycin and colistin, respectively. Isolated strains were compared with geographical, month and sample. The distribution of 16 isolated Vibrio parahamolyticus was high at Hadong with 50%(8 strains), on July with 43.8%(7 strains) and from seawater with 37.5%(6 strains) respectively. Minimal inhibitory level of GFSE to Vibrio parahaemolyticus was 50 ppm. With 100 ppm treatment of GFSE, the destroy of cell membrane function, outflow of cell ingredients and ghost morphology of cell were investigated.

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Development of the Dredged Sediments Management System and Its Managing Criteria of Debris Barrier (사방댐 준설퇴적물 관리시스템 개발 및 관리기준 제안)

  • Song, Young-Suk;Yun, Jung-Mann;Jung, In-Keun
    • Journal of the Korean Geosynthetics Society
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    • v.17 no.4
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    • pp.267-275
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    • 2018
  • The dredged sediment management system was developed to have an objective, quantitative and scientific decision for the optimum removal time of dredged sediments behind debris barrier and was set up at the real site. The dredged sediment management system is designed and developed to directly measure the dredged sediments behind debris barrier in the field. This management system is composed of Data Acquisition System (DAS), Solar System and measurement units for measuring the weight of dredge sediments. The weight of dredged sediments, the water level and the rainfall are measured in real time using the monitoring sensors, and their data can be transmitted to the office through a wireless communication method. The monitoring sensors are composed of the rain gauge to measure rainfall, the load cell system to measure the weight of dredged sediments, and water level meter to measure the water level behind debris barrier. The management criteria of dredged sediments behind debris barrier was suggested by using the weight of dredged sediments. At first, the maximum weight of dredged sediments that could be deposited behind debris barrier was estimated. And then when 50%, 70% and 90% of the maximum dredged sediments weight were accumulated behind debris barrier, the management criteria were divided into phases of Outlooks, Watch and Warning, respectively. The weight of dredged sediments can be monitored by using the dredged sediment management system behind debris barrier in real time, and the condition of debris barrier and the removal time of dredged sediments can be decided based on monitoring results.