• Title/Summary/Keyword: WER

Search Result 173, Processing Time 0.02 seconds

Isolation and characterization of 4-chlorophenoxyacetic acid-degrading bacteria from agricultural soils

  • Chung, Min-Jae;Shin, Se-Young;Park, Yong-Keun;Min, Kyung-Hee;Ka, Jong-Ok
    • Journal of Microbiology
    • /
    • v.35 no.2
    • /
    • pp.117-122
    • /
    • 1997
  • Several dominant 4-CPA-degrading bacteria were isoalted from agricultural soils. Most of the isolates were identified as Burkholderia species by fatty acid methyl ester (FAME) analysis, but they were idstinct in chromosomal patterns obtained by PCR amplification of repetitive extragenic palindromic (REP) sequences. These strains were generally restricted in their substrate utilization capabilities. The 4-CPA degradative enzymes were idnducible by 4-CPA and some isolates appeared to mineralize 4-CPA via formation of 4-chlorophenol and 4-chlorocatechol as intermediates during its biodegradation pathway. Plasmid DNAs were not detected from most of the isoaltes and their 4-CPA genes wer on the chromosomal DAN. The 4-CPA degradation patterns in axenic cultures and natural soils varied depending on the strains and soils. The inoculation of 4-CPA degraders much improved the removal of 4-CPA from the 4-CPA treated soils.

  • PDF

Studies on the constituents of syringa oblata var. dilatata(Nakai) Rehder (Syringa oblata var. dilata (Nakai) Rehder의 성분 연구)

  • 유경수
    • YAKHAK HOEJI
    • /
    • v.1 no.1
    • /
    • pp.2-4
    • /
    • 1948
  • Syringa oblata var dilatata (Nakai) Rehder is a oleaceous, deciduous shrub indigenous in the calcareous zones of Korea. The author researched the constituents of the leaves of the plant, especially the bitter principles which may be used as amara. According to the literature a bitter principle Syringin and Mannitol were isolated from the leaves of S. vulgaris L. And later on B. Power indicated that syringin and mannitol were widely distributed in oleaceous plants. The fresh leaves of the plant wer extracted with hot water, the filtered clear liquid was mixed with solution of lead acetate. The lead precipitate was filtered off and the filtered liquid was freed from lead by H$_{4}$S. The filtrate thus obtained was evaporated, and from the residue colorless needles, M. P. 166.deg., were obtained. It was soluble in water, in hot alcohol, and insoluble in ether and had a sweet taste. The results of the elementar analysis, M. P. and other characteristics agreed with that of d-mannitol. Finally it was proved to be identical with d-mannitol through conversion of it into Hexaacetyl mannitol, M. P. 124.deg., Triformal mannitol, M. P. 227.deg., Tribenzal mannitol, M. P. 224.deg., which exhibited no depression, when mixed with authentic specimens. The experiments to isolate bitter principles of the plant are in progress.

  • PDF

Growth Charateristics of Five Microalgal Species Isolated from Jeju Island and Four Microalgal stock Strans in Hatchery

  • Lee, Joon-Baek
    • ALGAE
    • /
    • v.17 no.2
    • /
    • pp.117-125
    • /
    • 2002
  • Five microalgal species isolated from the Jeju coast and four microalgal stock strains in hatchery were cultured in order to investigate their adapation to extreme changes in environmental factors such as salinity, water temperatue, adn nutrients. In case of salinity variation, Nitzschia sp. of Bacillariophyceae, Isochrysis galbana of Haptophyceae and Tetraselmis gracilis of Prasinophyceae showed optimum growth at the low salinity of 20 and 25 psu. Amphora coffeaeformis and Chetoceros simplex of Bacillariophyceae, and Pavlova lutheri of Haptophyceae adapted well at the relatively high salinities of 30 and 35 psu. However Phaeodactylum tricornutum of Bacillariophyceae and Chlorella sp. of Chlorophyceae showed euryhaline property In case of water temperature variation, most of all the species studied wer inhibited at 10℃. C. simplex, Nitzschia sp., p. tricornutum, Chlorella sp. and T. gracilis grew well at above 20℃. A. coffeaeformis, I. galbana and P. lutheri adapted also at the high temperature of 30℃. Each microalgal strain showed different growth rates and its maximum biomass. Generally microalgal populations from the Jeju coast grow well in relatively high salinity and high water temperature. Their growth were inhibited at low water temperature, but not likely affected at low salinity. This study indicates that the microalgal populations could not be affected by abnormally low salinity phenomena, which have happened occasionally around the west Jeju coast in summer and have led macrobenthic animals to mass mortality.

Characterization of Bacillus thuringiensis Isolated in Granary Dusts (저곡창고에서 분리된 Bacilus thuringiensis의 특성조사)

  • 김호산;박현우;이대원;유용만;유용만;강석권
    • Korean journal of applied entomology
    • /
    • v.34 no.3
    • /
    • pp.243-248
    • /
    • 1995
  • In order to isolate naturally occurring novel Bacillus thuringiensis strains, we investigated the distribution of B. thuringiensis from granary which exist in Kyong-gi province, Korea. A total of 146 strains of B. thuringiensis producing spore and crystal wre isolated. The toxicity of B. thuringiensis isolates was examined against lepidopteran larvae (Bombyx mori), dipteran larvae (Culex pipiens) and coleopteran larvae (Sitophilus oryzae.), respectively. The results showed that a large number of B. thuringiensis isolates from granary dusts were isolated and most isolates wer toxic to lepidopterous larvae. Also, non-toxic B. thuringiensis isolate was common. In order to isolate many B. thuringiensis, therefore, it suggested that granary is favorable locality.

  • PDF

A Study on the Thermal Properties of Skirts (스커트의 열특성에 관한 연구)

  • Choi Hei-Sun
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.13 no.4
    • /
    • pp.388-399
    • /
    • 1989
  • The purpose of this study was to investigate the effects of garment design, fabric type and the presence of lining on the thermal insulation value $(I_{cle}\;and\;I{cl})$ and clothing area factor $(f_{cl})$ of skirts. A standing, electrically heated thermal maninkin was used to measure the insultation value of eighty skirts-five skirt styles with eight different fabrics, with and without lining. The air temperature of the chamber was set at $22.2^{\circ}C{\pm}0.5^{\circ}C$ , air velocity was limited to less than 0.1 m/s, and relative humidity was approximately $50\%$. The results are as follows: 1) The Ic, values of gathered skirt and flared skirt, which had high $f_{cl}$ values, were significantly higher than those of other skirts, though the highest $I_{cle}$ value among five styles wer pegged skirt. 2) Insulation values of various skirts were more relevant with physical properties such as thickness, air permeability, and thermal transmission of the materials rather than fiber content. 3) The addition of lining made significant difference in the insulation values of skirts and the differences of gathered and flared skirt were significantly higher than those of othere types of skirts.

  • PDF

Tracing of Some Root Colonizing Pseudomonas in the Rhizosphere Using lux Gene Introduced Bacteria (lux Gene을 도입한 생물적 방제 미생물의 근권 정착과 식물 생장 촉진 효과)

  • 김진우;최옥희;강지효;류충민;정미진;김재원;박창석
    • Korean Journal Plant Pathology
    • /
    • v.14 no.1
    • /
    • pp.13-18
    • /
    • 1998
  • The use of bioluminescence as a sensitive marker for the detection of Pseudomnas sp. in the rhizosphere was investigated. Transposon Tn4431 which contains a promoterless luciferase operon and tetracycline resistant gene was used. This transposon, present on a suicide vector (pUCD623) in E. coli HB101, was mated with spontaneous rifampicin mutant of Pseudomonas fluorescens B16, a plant growth promoting rhizobacteria (PGPR), and then rifampicin and tetracycline resistant survivors were isolated. Twenty tow mutants wer isolated from the conjugants between E. coli HB101 and P. fluorescens B16. One of these, B16::Tn4431 (L22) recombinant which glowed brightly in the dark was selected for analysis. The cucumber seeds inoculated with L22 were grown in moisten two layers of filter paper and nonsterile soil contained in half cut PVC pipe. The roots were removed from the filter paper and PVC pipe, then placed on the 1/2 LB media plates. The plates were incubated at room temperature for 16 hr. L22 could successfully be detected in the rhizoplane by using the ordinary negative camera film (ASA100-400) with 30 minutes exposure under dark condition. The root colonizing ability and the plant growth promoting effect of L22 were not reduced compared to the untreated bacteria and wild type. L22 was superior to will type.

  • PDF

A VQ Codebook Design Based on Phonetic Distribution for Distributed Speech Recognition (분산 음성인식 시스템의 성능향상을 위한 음소 빈도 비율에 기반한 VQ 코드북 설계)

  • Oh Yoo-Rhee;Yoon Jae-Sam;Lee Gil-Ho;Kim Hong-Kook;Ryu Chang-Sun;Koo Myoung-Wa
    • Proceedings of the KSPS conference
    • /
    • 2006.05a
    • /
    • pp.37-40
    • /
    • 2006
  • In this paper, we propose a VQ codebook design of speech recognition feature parameters in order to improve the performance of a distributed speech recognition system. For the context-dependent HMMs, a VQ codebook should be correlated with phonetic distributions in the training data for HMMs. Thus, we focus on a selection method of training data based on phonetic distribution instead of using all the training data for an efficient VQ codebook design. From the speech recognition experiments using the Aurora 4 database, the distributed speech recognition system employing a VQ codebook designed by the proposed method reduced the word error rate (WER) by 10% when compared with that using a VQ codebook trained with the whole training data.

  • PDF

Acoustic Radiation from a Finite-length Shell with Substructures Subjected to an Impulsive Load (부구조물이 있는 유한길이의 쉘 구조물에서의 충격하중에 의한 음향방사)

  • 최성훈
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 1995.10a
    • /
    • pp.62-67
    • /
    • 1995
  • A method for determining impulsive responses and acoustic radiation for submerged shells of finite length has been presented. The method is a modal-based method, and uses a surface variational principle to obtain data in the frequency domain. The fast Fourier transform technique is used to convert the data to the time domain. The surface pressure responses of a cylindrical shell with endcaps wer compared with those of an infinite shell. It was shown that the surface pressures coincide exactly before any significant reflections from the endcaps occur. Traces of different types of waves were identified from the dispersion relations of the infinite shell. The contributions of flexural and longitudinal waves and these due to the direct radiation from the driving force to the fluid pressure were demonstrated using near-field plots. The exchange of energy between the shell and fluid was examined for shells with and without bulkheads. It was shown that a significant amount of the energy which enters the fluid returns to the shell and most of the energy is dissipated in the shell. It was also shown that the shell with bulkheads radiate significantly more energy into the far-field than the empty shell.

  • PDF

Mechanical and Thermal Properties of Hydroxypropyl Cellulose/TEMPO-oxidized Cellulose Nanofibril Composite Films (Hydroxypropyl cellulose/TEMPO-산화 처리된 셀룰로오스 나노섬유를 이용한 복합필름의 기계적 및 열적 특성)

  • Jo, Yu-Jeong;Cho, Hye-Jung;Chun, Sang-Jin;Lee, Sun-Young
    • Journal of the Korean Wood Science and Technology
    • /
    • v.43 no.6
    • /
    • pp.740-745
    • /
    • 2015
  • Hydroxypropyl cellulose (HPC) composite films filled with TEMPO-oxidized cellulose nanofibrils (TOCN) were prepared in this study. In order to investigate mechanical and thermal properties of HPC/TOCN composite films, tensile strength and thermogravimetric analysis (TGA) wer performed. As the loading level of TOCN increased, the tensile strength and modulus increased significantly. However, thermal stability of HPC/TOCN composite films was not related to the loading levels of the TOCN.

Surgical analysis of pulmonary aspergilloma (폐국균종의 외과적 임상분석)

  • 이종국;박승일;서재정;원준호
    • Journal of Chest Surgery
    • /
    • v.33 no.3
    • /
    • pp.245-251
    • /
    • 2000
  • Backround: Pulmonary aspergilloma is a potential life-threatening disease resulting from massive hemoptysis. Pulmonary aspergilloma has been treated surgically for many years, however, it has also had higher risk of mortality and complication rate. The purpose of this study is to analyze the operative methods and the types of complications. Material and Method: Sixty patients who underwent surgical resection for pulmonary their medical reconrds. Result: The mean age was 46.3$\pm$13.4 years(range 20 to 76 years). The most common clinical presentation was hemoptysis which occurred in 48 patients(80%). Pulmonary tuberculosis was the most common pre-existing disease, occurri9ng in 28 patients(46.7%). The other associated lung diseases were bronchiectasis(n=11), silicosis(n=2), and chronic pnumonia(n=1). Operative proceudres wer lobectomy in 35 patients, pneumonectomy in 6, segmentectomy in 5, lobectomy and thoracoplasty in 3, segmentectomy and thoracopasty in 1, and cavernostomy in 10. The operative mortality was 6%(n=3) in lung resection patients but 0% in cavernostomy patients. The most common complications were prolonged air leakage, wound infection and postoperative bleeding. Conclusion: In most cases of pulmonary aspergilloma surgical resectin remains the only effective therapy. However, cavernostomy may be more effective for pulmonary aspergilloma patients with decreased pulmonary functions and for patients with high risk for lung resection.

  • PDF