• Title/Summary/Keyword: bacterial

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Bending Performance of Bacterial Cellulose Actuator under Water (수중에서 박테리아 셀룰로오스 작동기의 굽힘 성능)

  • Jeon, Jin-Han;Park, Min-Woo;Kim, Seong-Jun;Kim, Jae-Hwan;Oh, Il-Kwon
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2008.11a
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    • pp.203-204
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    • 2008
  • Bacterial Cellulose Actuator with biocompatible and biodegradable properties was newly developed as an electro-active biopolymer under water. The performance of the BC actuator was improved through Li treatment. The mechanical and chemical properties of BC membranes were measured such as the tensile test, proton conductivity. The surface morphology of the bacterial cellulose was observed by using SEM. The electromechanical bending responses under both direct current and alternating current excitations were investigated. In voltage-current test,the power consumption under dynamic excitation increases with increasing voltage. Present results show that the bacterial cellulose actuator can be a promising smart material and may possibly have diverse applications under water.

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The Therapeutic Effect of Piglets with Bacterial Diarrhea by Natural Honeybee (Apis mellifera) Venom. (생봉독을 이용한 세균성 설사 자돈의 치료효과)

  • 최석화;조성구;최향순;강성수;권영방
    • Journal of Veterinary Clinics
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    • v.16 no.1
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    • pp.150-154
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    • 1999
  • This study was designed to examine the therapeutic effect of Italian honeybee (Apis mellifera) venom in piglets with bacterial diarrhea. Preweaning piglets were assigned to treated and nontreated control groups. In treated group, 47 piglets were given natural honeybee venom once a day for 3 consecutive days. The natural honeybees were stung acupoints of GV-1 (Jiao-Chao, at the indentation between the base of tail and the anus) and ST-25 (Hai-men, about 1 cm lateral to the umbilicus). In control group, 44 piglets were intramuscularly injected with a standard dosage of colistin sulfate (300,000 IU/kg of body weight) and antid-iarrheal drug (berberine, 2 ml/kg) once a day for 3 consecutive days. At post-treatment, 90.9% of control piglets and 93.6 % of piglets in treated group recovered from bacterial diarrhea. Bee acupuncture therapy did not show in piglets without any side effects such as allergy, intoxication, hemorrhage, or infection. It might be concluded that honeybee venom therapy was effective in controlling of piglets with bacterial diarrhea.

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Biological Control of Fusarium Wilt by Antagonistic Microorganism in Greenhouse Grown Cucumber Plants (오이의 온실재배에서 발생하는 위조병의 미생물학적 제어)

  • Cho, Jung-Il;Cho, Ja-Yong
    • Korean Journal of Organic Agriculture
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    • v.12 no.1
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    • pp.101-114
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    • 2004
  • This study was carried out to clarify the effects of antagonistic microorganism, Bacillus sp. JC181 isolated from the greenhouse soil grown cucumber plants on the growth inhibition of plant pathogen, fusarium wilt (Fusarium oxysporum) occurred in cucumber plants in greenhouse. Antagonistic bacterial strains were isolated and were investigated into the antifungal activity of the antagonistic microorganism against fusarium wilt. Screened fourteen bacterial strains which strongly inhibited F. oxysporum were isolated from thc greenhouse soil grown cucumber plants, and the best antagonistic bacterial strain designated as JC181, was finally selected. Antagonistic bacterial strain JC181 was identified to be the genus Bacillus sp. based on the morphological and biochemical characterization. Bacillus sp. JC181 showed 58.2% of antifungal activity against the plant pathogen growth of F. oxysporum. By the bacterialization of culture broth and heated filtrates of culture broth, Bacterial strain, Bacillus sp. JC181. showed 91.2% and 260% of antifungal activity against F. oxysporum, respectivrly.

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Biomineralization of Calcium Carbonate Polymorphs by the Bacterial Strains Isolated from Calcareous Sites

  • Dhami, Navdeep Kaur;Reddy, M. Sudhakara;Mukherjee, Abhijit
    • Journal of Microbiology and Biotechnology
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    • v.23 no.5
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    • pp.707-714
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    • 2013
  • Microbially induced calcium carbonate precipitation (MICCP) is a naturally occurring biological process that has various applications in remediation and restoration of a range of building materials. In the present investigation, five ureolytic bacterial isolates capable of inducing calcium carbonate precipitation were isolated from calcareous soils on the basis of production of urease, carbonic anhydrase, extrapolymeric substances, and biofilm. Bacterial isolates were identified as Bacillus megaterium, B. cereus, B. thuringiensis, B. subtilis, and Lysinibacillus fusiformis based on 16S rRNA analysis. The calcium carbonate polymorphs produced by various bacterial isolates were analyzed by scanning electron microscopy, confocal laser scanning microscopy, X ray diffraction, and Fourier transmission infra red spectroscopy. A strain-specific precipitation of calcium carbonate forms was observed from different bacterial isolates. Based on the type of polymorph precipitated, the technology of MICCP can be applied for remediation of various building materials.

Bioelectrochemical Denitrification by Pseudomonas sp. or Anaerobic Bacterial Consortium

  • Park, Doo-Hyun;Park, Yong-Keun
    • Journal of Microbiology and Biotechnology
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    • v.11 no.3
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    • pp.406-411
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    • 2001
  • In a bacterial denitrification test with Pseudomonas sp. and anaerobic consortium, more nitrates and less substrate were consumed but less metabolic nitrite was produced under an anaerobic $H_2$ condition rather than under $N_2$ condition. In a bioelectrochemical denitrification test with the same organisms, the electrochemically reduced neutral red was confirmed to be a substitute electron donor and a reducing power like $H_2$. The biocatalytic activity of membrane-free bacterial extract, membrane fraction, and intact cell for bioelectrochemical denitrification was measured using cyclic voltammetry. When neutral red was used as an electron mediator, the electron transfer from electrode to electron acceptor (nitrate) via neutral red was not observed in the cyclic voltammogram with the membrane-free bacterial extract, but it was confirmed to gradually increase in proportion to the concentration of nitrate in that of the membrane fraction and the intact cell of Pseudomonas sp.

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Structure and function of chemotactic transducer proteins

  • Park, Chankyu;Ha, L.zelbaure
    • The Microorganisms and Industry
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    • v.12 no.2
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    • pp.14-18
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    • 1986
  • Barcterial chemotaxis is a transient response of an organism in a situation where environmental homogeneity has been disturbed by certain chemical compounds. The phenomenon has been described in motile bacterial species including enteric bacteria, Gram-positives(14), Spirochaetes (6) and even Archaebacteria (8). However, most comprehensive studies have been done with Escherichia coli and Salmonella typhimurium. Two analogies to higher eucaryotic sensory phenomena are provided by the study of bacterial chemotaxis. First, bacterial chemotaxis is similar to the stimulus-response of neuronal, immune and sperm cells. Second, studies of individual components involved in the bacterial sensory pathway can contribute to the understanding of the function of receptors, controling signals and molecular comparators in transmembrane signalling system. The bacterial sensory transducer, a chemoreceptor in a broad sense, is a unique entity for studying sensory function in which sensory reception, signalling and adaptation are integrated (7,18).

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Robust Tuning of PID Controller With Disturbance Rejection Using Bacterial Foraging Based Optimization

  • Kim, Dong-Hwa;Cho, Jae-Hoon
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.1092-1097
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    • 2005
  • In this paper, design approach of PID controller with rejection function against external disturbance in motor control system is proposed using bacterial foraging based optimal algorithm. Up to the present time, PID Controller has been used to operate for AC motor drive because of its implementational advantages in practice and simple structure. However, it is not easy to achieve an optimal PID gain with no experience, since the gain of the PID controller has to be manually tuned by trial and error in the industrial system with disturbance. To design disturbance rejection tuning, disturbance rejection conditions based on $H_{\infty}$ are illustrated and the performance of response based on the bacterial foraging is computed for the designed PID controller as ITSE (Integral of time weighted squared error). Hence, parameters of PID controller are selected by bacterial foraging based optimal algorithm to obtain the required response

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Intelligent Tuning of PID Controller With Disturbance Rejection Using Bacterial Foraging

  • Kim, Dong-Hwa;Cho, Jae-Hoon
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2004.10a
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    • pp.15-20
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    • 2004
  • In this paper, design approach of PID controller with rejection function against external disturbance in motor control system is proposed using bacterial foraging based optimal algorithm. Up to the present time, PID Controller has been used to operate for AC motor drive because of its implementational advantages in practice and simple structure. However, it is not easy to achieve an optimal PID gain with no experience, since the gain of the PID controller has to be manually tuned by trial and error in the industrial system with disturbance. To design disturbance rejection tuning, disturbance rejection conditions based on H$\_$$\infty$/ are illustrated and the performance of response based on the bacterial foraging is computed for the designed PID controller as ITSE (Integral of time weighted squared error). Hence, parameters of PID controller are selected by bacterial foraging based optimal algorithm to obtain the required response.

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Occurrence of Bacterial Soft Rot of Soybean Sprout Caused by Erwinia carotovora subsp. carotovora (Erwinia carotovora subsp. carotovora에 의한 콩나물 무름병 발생)

  • 박종철;송완엽;김형무
    • Korean Journal Plant Pathology
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    • v.13 no.1
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    • pp.13-17
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    • 1997
  • A causal agent of bacterial soft rot occurring in soybean sprout cultivation in Korea was isolated and identified, and its incidence in several sprout-soybean cultivars was examined. Infected soybean seeds became light brown and whitish, and could not germinate until 3 days after seeding, accompanying rotting of soybean seeds and sprouts. The causal organism isolated from the rotten seeds and sprouts was identified as Erwinia carotovora subsp. carotovora on the basis of its pathogenicity, morphological and physiological characteristics and the results of the Biolog GN microplate test program. The bacterial soft rot by E. c. subsp. carotovora was firstly described in soybean sprout in Korea, and we name it“the bacterial soft rot of soybean sprout”. The disease occurred more frequently in Nam-hae and Fu-reun sprout-soybean cultivars than in Eun-ha, So-baek, and Ik-san cultivars.

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Bacterial Soft Rot of Elephant Foot Caused by Erwinia carotovora subsp. carotovora (Erwinia carotovora subsp. carotovora에 의한 구약감자 무름병(신칭))

  • Choi Jae Eul;Park Jong Seong;In Moo Seung;Ahn Byeong Chang
    • Korean Journal Plant Pathology
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    • v.3 no.3
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    • pp.236-238
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    • 1987
  • A bacterial disease of elephant foot, Hydrosome rivieri Engl., was newly found in Taejon, Korea in August 1986. The affected plants showed symptoms of soft rot on leaf blades and petioles. Bacterial isolates from affected plants found to be pathogenic to elephant foots by antificial inoculation, producing similar symptoms with those produced naturally. The baterium was also pathogenic to carrot, Chinese cabbage, radish, potato and onion, and developed symptom of soft root on them. On the basis of bacteriological characteristics and pathogenicity, tested bacterium was identified as Erwinia carotovora subsp. carotovora and this disease was proposed to name 'Bacterial soft rot of elephant foot'.

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