• Parasites, Hosts and Diseases
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• 제28권3호
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• pp.143-154
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• 1990

병원성이 강한 Acanthamoeba culbertsoni에 감염된 마우스를 감염 정도에 따라 경(輕)감염, 중(中)등 감염, 중(重)감염 실험군으로 나누었을 때 감염 기간에 따라 발현되는 세포 매개성 면역반응의 차이를 지연형 과민반응, T와 B림프구의 아세포화 정도 및 자연 살세포의 독성을 통하여 곤찰하고 또한 혈청내 항체가를 측정하였다. 감염 마우스의 사망율은 $3{\times}10^3$개의 아메바 영양형을 감염시킨 경(輕) 감염군에서는 17%였으며, $1{\times}10^4$개를 감염시킨 중(中)등 감염군에서는 34%, $1{\times}10^5$개를 감염시킨 중(重) 감염군에서는 65%였다. 세포 매개성 면역을 관찰하기 위한 지연형 과민반응의 변동을보면 각 실험군 모두에서 감염 후 7일째 발바닥의 두께가 유의하게 증가하였으나 감염 후 14일째에는 감소하였고 각 실험군 간에 유의한 차이를 발견할 수 없었으며 각 실험군과 대조군 간에도 유의한 차이가 없었다. A. culbertsoni lysate 및 B 림프구 mitogen인 LPS에 의한 비장세포의 아세포화는 관찰되지 않았으며, T림프구 mitogen인 con. A로 처리한 비장세포의 아세포화 정도는 각 실험군 모두에서 감염 7일 이후 대조군에 비해 유의하게 감소하였으며 B림프구 mitogen인 poly I 처리시는 실험군 모두에게 대조군과 차이가 없었다. 그리고 con. A와 poly I에 의한 아세포화 정도에 있어서 각 실험군 간에 유의한 차이를 관찰할 수 없었다. 자연살세포의 세포 독성은 실험군 모두에게 대조군에 비해 감염 후 1일째에 증가되었고 감염 후 5일째에는 유의하게 감소하였다. 그러나 각 실험군 간에 세포독성의 유의한 차이는 발견할 수 없었다. 혈청내 항체가는 각 실험군 모두에서 감염 7일 이후부터 대조군에 비해 계속 증가하였으나 각 실험군 간에 유의한 차이를 발견할 수 없었다.

• Mycobiology
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• 제32권2호
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• pp.79-87
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• 2004

An experiment was carried out to investigate the effects of pre-inoculation with the mycorrhizal fungus Glomus clarum and foliar application of kinetin on the growth of mungbean plant irrigated wht different dilution of seawater. Arbuscular-mycorrhizal(AM) infection significantly increased dry weight, height, chlorophyll, sugar and protein content, nitrogen and phosphorus-use efficiencies, leaf conductivity, transpiration rate, nitrogenase, acid and alkaline phosphates activities of all salinized mungbean plants in comparison with control and non-mycorrhizal plants irrespective of the presence or absence of kinetin. Mycorrrhizal plants showed higher concentrations of N, P, K, Ca and Mg and lower Na/N, Na/P, Na/K, Na/Ca and Na/Mg ratios than non-mycorrhizal plants when irrigated with certain dilution of seawater. Mungbean plants showed 597% and 770% dependency on AM fungus G. clarum in absence and presence of kinetin, respectively, for biomass production under a level of 30% of seawater. The average value of tolerance index for mycorrhizal plants accounted 267% and 364% in absence and presence kinetin respectively. This study provides evidence for the benefits of kinetin which are actually known for mycorrhizal than non-mycorrhzal plants. AM fungus and kinetin protected the host plants against the detrimental effects of salt. However, mycorrhizal infection was much more effective than kinetin applications. Thus management applications of this arbuscular mycorrhizal endophyte(G. clarum) with kinetin could be of importance in using seawater in certain dilution for irrigation in agriculture.

• 대한수의학회지
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• 제62권4호
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• pp.30.1-30.6
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• 2022

In the study, zinc oxide nanoparticles (ZNOPs) at concentrations of 20, 40, and 60 mg/kg were tested for their antimicrobial action against the oocysts of Eimeria tenella. The oocysts of E. tenella were isolated from the feces of broilers received at the veterinary hospital in Diwaniyah Province and initially diagnosed by compound optical microscopy. The oocysts were confirmed molecularly by polymerase chain reaction targeting the ITS1 gene with a molecular weight of 409 bp. The results in the first week showed that ZNOP concentrations of 20 and 40 mg/kg possess various activities against E. tenella, while 60 mg/kg was the most effective in reducing excreted oocysts compared to the positive control and amprolium group, along with the appearance of mild symptoms and a mortality rate of 0.8%. In the second week of infection, excreted oocysts and mortality rates generally decreased in all treated groups. A comparison of all groups showed that the 60 mg/kg ZNOP-treated group had a significantly lower number of excreted oocysts, and all birds in this group recovered during the second week of infection. These findings revealed the prospect of using ZNOPs against E. tenella in challenging situations of the appearance of resistance to anticoccidial agents.

• 한국응급구조학회지
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• 제9권1호
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• pp.43-53
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• 2005

The purpose of this study was to survey a perception of frequency & importance level of job performance, from 249 paramedics who were working at fire station. The job related activities of 4 duties, 18 tasks and 145 task elements were checked by 4 rating scale. The data were analyzed using a SPSS program for descriptive statistics. The results of the study were as follows ; 1. Some of the most frequent tasks were medical tx, managing people & organization, trauma care, pt assessment, general coping skill 2. Some of the most frequent task elements were preparation of written reports, operation of pt lifting supplies, transportation of patients on stretchers, administration of cervical collar and utilization of scoop stretcher. 3. Some of the highest level of importance in task were resuscitation of circulation, surgical tx, safety & infection control, environmental emergency care, trauma care. 4. Some of the highest level of importance in task elements were administration of cervical collar, adult CPR, infant CPR, child CPR, and AED. 5. The highest level of task elements in perception of frequency & importance were administration of cervical collar, infection control after pt care, utilization of long back board, disinfection of ambulance after ride a long, care of chest pain pt, care of unconscious pt, tx of asthma. 6. A difference between frequent & importance score were due to lack of supplies(41%), structural problems(30%) and medical control system(16%), lack of skills(10%), Suggestion; 1. This paper would be more reliable and confirm through wilder range of survey. 2. It would be necessary of more depth survey through dacom study from paramedic. 3. Development of field oriented protocol & curriculum that based on task elements which have high score of both frequency & importance level is required.

• The Plant Pathology Journal
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• 제37권4호
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• pp.315-328
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• 2021

Fusarium and Rhizoctonia genera are important pathogens of many field crops worldwide. They are constantly evolving and expanding their host range. Selecting resistant cultivars is an effective strategy to break their infection cycles. To this end, we screened a collection of Medicago truncatula accessions against Fusarium oxysporum, Fusarium solani, and Rhizoctonia solani strains isolated from different plant species. Despite the small collection, a biodiversity in the disease response of M. truncatula accessions ranging from resistant phenotypes to highly susceptible ones was observed. A17 showed relative resistance to all fungal strains with the lowest disease incidence and ratings while TN1.11 was among the susceptible accessions. As an initiation of the characterization of resistance mechanisms, the antioxidant enzymes' activities, at the early stages of infections, were compared between these contrasting accessions. Our results showed an increment of the antioxidant activities within A17 plants in leaves and roots. We also analyzed the responses of a population of recombinant inbred lines derived from the crossing of A17 and TN1.11 to the infection with the same fungal strains. The broad-sense heritability of measured traits ranged from 0.87 to 0.95, from 0.72 to 0.96, and from 0.14 to 0.85 under control, F. oxysporum, and R. solani conditions, respectively. This high estimated heritability underlines the importance of further molecular analysis of the observed resistance to identify selection markers that could be incorporated into a breeding program and thus improving soil-borne pathogens resistance in crops.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제15권1호
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• pp.47-55
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• 2009

악성봇은 해커에 의해 원격 조정되어 명령에 의해 스팸메일 발송, DDoS 공격 등의 악성행위를 수행하는 웜/바이러스 이다. 악성봇은 이전의 웜/바이러스와 달리 금전적인 이득을 목적으로 하는 경우가 많은 반면 감염사실을 피해자가 인지하기 쉽지 않아 피해가 심각한 실정이다. 이에 대한 대응 방안으로는 해커의 명령을 전달하는 명령/제어 서버의 차단이 필요하다. 이 중 악성봇 DNS 싱크홀 기법이 국내에서 적용하고 있는 봇 대응 시스템으로, 본 논문의 목적은 이 방식의 효과성을 제시하는데 있다. 본 논문에서는 1년 이상의 장기간 동안 악성봇 및 Botnet 을 관찰하여 Bot 감염 PC의 감염 지속시간, Bot 명령/제어 서버의 특성 등을 파악하고, 악성봇의 피해를 방지하기 위한 효과적인 방안인 악성봇 DNS 싱크흘의 적용 결과를 분석한다. 이를 위하여 웜샘플 분석 툴을 이용하여 자동 분석체계를 구축하였고, 이를 시스템화 하였다. 또한, 분석을 통해 현재 국내에서 적용되고 있는 봇 대응 시스템의 타당성을 검증하였다.

• 한국수산과학회지
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• 제46권5호
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• pp.552-558
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• 2013

This study was performed to determine effects of the supplementation of Kimchi lactic acid bacterial culture in extruded pellets (EP) on the growth, body composition, blood chemistry and immune response of olive flounder Paralichthys olivaceus. Four hundred eighty individuals averaging 16.1 g were randomly distributed into 12, 180 L flow-through tanks (forty fish per tank). Four concentrations of Kimchi lactic acid bacterial culture (KL) were prepared: Control (0%), 0.1%, 0.2% and 0.5%. Three concentrations (0.1%, 0.2% and 0.5%) of Kimchi lactic acid bacterial culture were each diluted to 10% of EP weight and then fully absorbed by EP for 10 minutes. Each diet was fed to triplicate groups of fish. Fish were hand-fed to apparent satiation twice a day for 8 weeks. At the end of the 8-week feeding trial, the plasma lysozyme and bacterial activities of fish were determined. In addition, the cumulative mortality of fish was monitored for 8 days after their artificial infection with Edwardsiella tarda. The weight gain, specific growth rate, feed efficiency ratio, protein efficiency ratio, protein retention, hepatosomatic index and condition factor of fish were not affected by dietary supplementation with KL. None of the proximate composition, plasma parameters, lysozyme or bactericidal activities of fish was affected by dietary supplementation with KL. However, the cumulative mortalities of fish fed EP containing 0.1% and 0.5% Kimchi lactic acid bacterial culture were relatively low compared to that of fish fed the control diet. In conclusion, dietary supplementation with KL did not effectively improve growth, feed utilization, body composition, plasma chemistry, lysozyme, bactericidal activities or immune response of olive flounder after E. tarda infection under these experimental conditions.

• 한국환경복원기술학회지
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• 제5권2호
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• pp.53-62
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• 2002

The objectives of this study were to understand the tolerance mechanism of woody plants to water stress and tolerance changes in relation to mycorrhizal formation. Lespedeza cyrtobotrya Miq. commonly used for erosion control in slopes were raised from seeds and transplanted to 120 plastic pots. Sixty pots received the top soil of a Fraxinus americana forest, while remaining 60 pots received the autoclaved top soil. The forest soil contained 1,200 spores per 100g of arbuscular endomycorrhizal fungus, mostly Glomus sp. The plants were raised outside with regular supply of water and mineral nutrients. Two kinds of water deficit treatment and a control were started at the middle of July : cyclic water deficit treatment with 3 cycles of sequential water stress at the point of xylem water potential of about -0.6, -0.6, and -1.7 MPa and recovery, and non-cyclic water deficit treatment with single water stress at about -1.5 MPa. The non-stressed plants received plenty of water throughout the period. In late August the plants were harvested for measurements of dry weight, N, P, carbohydrate contents, net photosynthesis and superoxide dismutase(SOD) activities. Both cyclic and non-cyclic water deficit treatments reduced dry weight by 60% and 40%, respectively, and reduced nitrogen absorption, while increased SOD activities. Water-stressed plants also showed increased carbohydrate contents in the leaves and lowered stomatal conductance. Mycorrhizal inoculation resulted in an average of 40% infection of roots and 2-3 times increase in P absorption in water-stressed as well as non-stressed plants. Mycorrhizal formation also increased shoot-root ratio. The results that SOD activities of water-stressed plants with mycorrhizal infection were significantly lower than those of non-mycorrhizal plants suggest the possibility of improvement of water-stressed condition by mycorrhizal formation. It was concluded that endomycorrhizal formation increased tolerance of Lespedeza cyrtobotrya seedlings to water stress.

• The Plant Pathology Journal
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• 제25권3호
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• pp.270-279
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• 2009

During the course of a study to develop a spraying program at 15-day spray intervals, two important findings were identified allowing for further reduction of spray frequency by increasing the spray interval. In evaluating the contribution of fungicides from a 15-day spray interval program, control of white rot, which is of prime importance in Korea, was not affected, in spite of the extended spray interval caused by omitting the fungicides during the season. In another experiment assessing the duration of the protective activities of several key fungicides used in the 15-day spray interval program, infection control was maintained for almost 30 days for some fungicide. Based on these two findings, a basic spraying program with a 25-day spray interval was developed. This program was modified for four successive years to improve the control efficacy against bitter rot and Marssonina blotch, which sometimes causes as much damage as white rot.

• 한국미생물·생명공학회지
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• 제44권3호
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• pp.261-267
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• 2016

본 연구에서는 호염성 세균 Bacillus sp. Mk22를 사료에 섞어 투여함으로써 Penaeus monodon 새우의 성장증진과 Vibrio parahaemolyticus 와 흰반점바이러스(WSSV)의 감염 감소에 대한 영향을 조사하였다. 새우는 45일 동안 3가지 먹이를 공급하였 는데, 무첨가(대조구), 시판 프로바이오틱, 그리고 Bacillus sp. Mk22이었다. 호염성세균 Mk22를 투여한 새우들은 다른 그룹들의 새우들보다 성장(7.1 ± 0.21 g), 생존율(94.3 ± 0.58%), 체중증가(178 ± 4.93 g), 그리고 감소된 사료전환효율(0.8 ± 0.03 g)을 보였다. Bacillus sp. Mk22를 투여한 새우들은 다른 그룹의 새우들보다 새우배양 수조안에서 낮은 비브리오 수자(0.02 ± 0.01 × 10² CFU/ml)를 보였다. 이 세 그룹의 새우들을 비브리오나 WSSV로 공격감염을 하였다. 비브리오 감영에서는, 시판 프로바이오틱그룹과 Mk22 그룹에서 배양수조의 물 감염과 경구투여감염에서 치사 새우가 없었다. WSSV 감염에 대해서는, Mk22 그룹의 경우 새우배양 수조 감염에서는 68%의 생존율과 경구투여 감염에서는 20% 생존율이 45일째에 관찰되었고, 대조구와 시판 프로바이오틱 그룹에서는 모두 훨씬 빠른 시간 내에 100% 사망률을 보였다. 산화적 스트레스의 표지인, catalase와 superoxide dismutase와 같은 항산화 효소 활성은 비브리오와 WSSV 감염된 Mk22 그룹 모두에서 다른 그룹들에 비해 유의적으로 감소하였다. 이 사실은 Bacillus sp. Mk22는 산화적 스트레스 감소하는데 효과적이었고, 이는 감소된 감염효과로 인한 것으로 추정된다.