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Assessment of the Activities of General Physicians in Health Subcenters and a Scheme to Improve the Training Program (보건지소 공중보건 일반의사의 업무수행정도와 수련개선방안)

  • Park, Jung-Han;Chun, Byung-Yeol;Woo, Kuck-Hyeun
    • Journal of Preventive Medicine and Public Health
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    • v.19 no.2 s.20
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    • pp.193-202
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    • 1986
  • The activities of general physicians (GPs) in health subcenters and their competency for clinical skills were assessed to develop a scheme to improve the training program. One hundred-twenty GPs in southern four provinces (Kyungpook, Kyungnam, Chunpook, Chunnam) were randomly selected and 97 were interviewed between January 9 and February 10, 1984. Of the 97 GPs, 86 provided all the information we requested. Average number of patient visits per health subcenter in a day was 30-40 in the demonstration project area for the class II medical insurance whereas it was 3-4 visits in other area. The interviewees were asked to rate their competency in 63 clinical skills. The skills in which over 50% of the interviewees rated themselves competent were only 12 items including IM injection, IV injection, wound dressing, etc. Less than 10% of the interviewees rated themselves competent in such skills as maternal health care, emergency medical care, preventive and promotive health services. Most part of the training program of the NIH for the GPs were not applicable to their field work as the training contents were unrealistic. Clinical training at a local general hospital was of great help in 38.8% and the rest of training was not much helpful as the training was inadequate due to lack of trainer or indifference of the trainer. For more effective training of the GPs, the training program of the NIH should be modified to be more realistic and utilize competent field workers as the instructors. It may be more effective if the training is carried out at several local centers. Ideal length of the clinical training for the GPs is 4 months. A pocketbook should be developed that includes specific skills to master during the clinical training and require the trainer to confirm the achievement. The Ministry of Health and Social Affairs should provide the training hospitals with a training guideline and evaluate the training activities and make sure that the training hospital has specialist for each of the 4 major clinical departments. The Ministry of Health and Social Affairs should provide the GPs with a continuing education to assist the problem solving in the field and motivate them to actively carry out the health program. A province may be divided into several regions and a supervisory committee may be organized with specialists in each region. The committee may hold a meeting for the GPs periodically and respond to the specific questions of the GPs by mail.

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Distribution Characteristics and Overwintering of Golden apple snails, Pomacea canaliculata (Gastropoda:Ampullariidae) at the Environment-friendly complex in Korea (한국 친환경농업단지의 왕우렁이 월동 및 분포특성)

  • Shin, I-Chan;Byeon, Young-Woong;Lee, Byung-Mo;Kim, Jurry;Yoon, Hyun-Jo;Yoon, Ji-Young;Lee, Young-Mi;Han, Eun-Jung;Park, Sang-Gu;Kuk, Yong-In;Choi, Duck-Soo;Cho, Il Kyu;Hong, Sung-Jun
    • Korean Journal of Environmental Agriculture
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    • v.40 no.4
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    • pp.279-289
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    • 2021
  • BACKGROUND: Recently, the golden apple snail, Pomacea canaliculata has been used as an environmentally-friendly weed-control agent in rice farming. Although effective for this particular style of farming, P. canaliculata can be destructive to other crops. The objective of this study was to identify overwintering as well as regional and seasonal distribution characteristics of P. canaliculata. Notably, winter is typically fatal for P. canaliculata. However, owing to increasing average global temperatures, we assessed the ability of P. canaliculata to survive through uncharacteristically warm winters. METHODS AND RESULTS: To examine the distribution and overwintering regions of P. canaliculata, We conducted a survey from April 2020 to May 2021 on environmentally-friendly rice fields, agricultural waterways, and streams in 23 cities belonging to 8 provinces. In addition, because air temperature may influence the distribution density of P. canaliculata, we analyzed the winter temperature data (http://weather.rda.go.kr). CONCLUSION(S): In 2021, overwintering of P. canaliculata (1-3 individuals/m2) was observed in the Goheung and Yeongam regions in Jeonnam. Overwintering of P. canaliculata was observed in fewer regions in 2021 than in 2020; this fact may be attributed to the lower minimum temperatures measured in 2021 (approximately 8℃ lower) than those in 2020. Our results suggest that overwintering occurs as long as overnight temperatures are ≥ -15℃, but can take place if temperatures are as low as -19℃.

The Revision of the Rules of the Workers' Party of Korea and the Organizational Changes of the 'Monolithic Guidance System of the Party Core': Focusing on Party-Government-Military Relations in Kim Jong Un Regime (조선노동당 제8차대회 당규약 개정과 '당중앙의 유일적 영도체계'의 조직적 변화: 김정은 정권의 당정군관계를 중심으로)

  • Kim, Tae-Kyung;Lee, Jung Chul;Yang, Hui
    • Analyses & Alternatives
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    • v.6 no.1
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    • pp.115-162
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    • 2022
  • The Rules of the Workers' Party of Korea (WPK), revised at the eighth Party Congress in 2021, reflect the Kim Jong Un regime's changes in strategic lines and ideological justifications on North Korea's socialism and communism, and its recent stances against the external environment. Moreover, they contain critical changes in the party's organizational system encompassing the central and the provinces. This study explores the organizational changes of the "monolithic guidance system of the party core" stipulated by the new party rules in January 2021, based on the analysis of the entire nine revised rules of the WPK since 1945. In the 2021 Party Congress, the Kim Jong Un regime, which officially came to power after the fourth Party Conference in 2012, has institutionalized the monolithic guidance system centered on the party core, or the head of state, Kim Jong Un. The newly set leadership and execution system, which reorganized party, government, and military organizational structure and accompanied the relevant personnel changes, was derived from the attempts for reinstating the Kim Jong Un regime as a more normalized party-state structure before its 10th year in power in April 2022. The "monolithic leadership system of the party core" established a system of "organizational leadership" through the organization of the Central Committee, directed by the Party Head, or General Secretary. The institutionalization of the new system resulted from the ten-year development of the revival of the party-state structure, which compromised the status of the military and reconfirmed the party's control of the military. This study explains the new system from the perspectives of both institutionalization and top-down unity, shedding light on the new party-military-government relations of the Kim Jong Un regime. The analysis contributes to a better understanding and forecasting of the Kim Jong Un regime's governance, which currently strengthens the monolithic leadership system as a crisis management system in the face of the "triple hardships" of sanctions, Covid and disaster.

Growth Characteristics and Yields of Native Summer Forage Crops as Affected by Seeding Rate in No-Tillage Paddy Fields (무경운 논에서 하계 자생사료작물의 파종량이 생육특성 및 수량에 미치는 영향 )

  • Jeong Sung Jung;Bo Ram Choi;Se Young Lee;Mirae Oh;Hyung Soo Park;Ki Choon Choi
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.43 no.1
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    • pp.28-34
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    • 2023
  • This experiment was carried out to determine effects of seed rate of native grasses, called native summer forage crops (NSFC), on their growth characteristics and yields in no-tillage paddy fields in central provinces. NSFC cultivation was performed according to the agricultural guidelines of the Rural Development Administration (RDA) during 2020 to 2022. Echinochloa crusgalli 'Jeju native', Setaria viridis 'Korean native type', Digitaria sanguinalis 'Korean native type') were sown by various seed rate in the experimental field (3m × 4m plot) of Department of Animal Resources Development, Seonghwan-eup, Cheonan, Korea in late-May or early-June for 3 years and harvested in middle-September. Dry matter yields (DMY) in Echinochloa crusgalli and Setaria viridis increased as increasing seed rate. DMY in 40 kg ha-1 of Echinochloa crusgalli was the highest and DMY in 60 kg ha-1 of Setaria viridis was the highest. However, All treatments of Digitaria sanguinalis showed similar DMY. Yields of NSFC were the order of Echinochloa crusgalli (9,681~11,092 kg ha-1) > Digitaria sanguinalis (8,311~9,023 kg ha-1) >etaria viridis (3,145~4,749 kg ha-1). The contents of crude protein in NSFC were the order of Digitaria sanguinalis > Echinochloa crusgalli > Setaria viridis. The contents of ADF and NDF in NSFC were the order of Echinochloa crusgalli > Digitaria sanguinalis > Setaria viridis. As shown in above results, we suggest that introduction of NSFC is one of the most important skills in order to stably increase yields of forage crops for utilization of the double cropping system in no-tillage paddy fields.

Analysis of Pedigree Structure and Inbreeding Coefficient for Performance Tested Holstein Cows in Korea (우리나라 Holstein 능력검정 젖소 집단의 혈통구조 및 근교계수 분석)

  • Won, J.I.;Dang, C.G.;Lim, H.J.;Jung, Y.S.;Im, S.K.;Lee, J.K.;Kim, J.B.;Cho, M.R.;Min, H.L.;Yoon, H.B.
    • Journal of agriculture & life science
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    • v.50 no.2
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    • pp.107-116
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    • 2016
  • The study was aimed to analyze pedigree structure and inbreeding coefficients for performance tested Holstein cows in Korea. A total of 400,029 Holstein cows data which born between 2002 and 2012 were obtained from Dairy Cattle Improvement Center of National Agricultural Cooperative Federation(NACF). Their related pedigrees, as obtained from Korean Animal Improvement Association(KAIA), consisted of 509,740 animals. Pedigree depth of the cows were traced back to 3 generations earlier. The percentage of cows with fully identified ancestors in various provinces of Korea were 55.18%(Gyeonggi-do), 23.49%(Gangwon-do), 47.83%(Chungcheongnam-do), 53.62%(Chungcheongbuk-do), 56.38%(Gyeongsangbuk-do), 51.35% (Gyeongsangnam-do), 26.58%(Jeollanam-do), 49.41%(Jeollabuk-do), and 56.90%(Jeju-do), whereas, it was about 63.20% as a whole in Korea. The average inbreeding coefficients showed increment across the consecutive years of birth such as, 0.43(2002), 0.44(2003), 0.58(2004), 0.64(2005), 0.78(2006), 0.93(2007), 1.08(2008), 1.23(2009), 1.46(2010), 1.77(2011), and 2.03 (2012). However, this coefficient was 0.93 in overall Korean population. An average generation interval for sire to daughter genetic path was 8.15 years; which was about 4.20 years considering dam to daughter genetic path. The estimated effective population sizes (Ne) were 56.5, 51.3, and 32.2 animals born in 2004, 2009, and 2012, respectively. These results indicated that an increased rate of inbreeding has led to a significant reduction in the Ne over the decade.

A Survey on the Break-down and Repair of the Power Tillers in Korea (동력경운기(動力耕耘機) 이용실태(利用實態) 조사분석(調査分析)(II) -고장(故障) 및 수리(修理)에 관(關)하여-)

  • Hong, Jong Ho;Lee, Chai Shik
    • Journal of Biosystems Engineering
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    • v.6 no.1
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    • pp.28-38
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    • 1981
  • A survey has been conducted to investigate the presents of breaks down and repair of power tiller for efficient use. Eight provinces were covered for this study. The results are summarized as follows. A. Frequency of breaks down. 1) Power tiller was breaken down 9.05 times a year and it represents a break down every 39.1 hours of use. High frequency of breaks down was found from the fuel and ignition system. For only these system, the number of breaks down were 2.02 and it represents 23.3% among total breaks down. It was followed by attachments, cylinder system, and traction device. 2) For the power tiller which was more than six years old, breaks down accured 37.7 hours of use and every 38.6 hours for the power tiller which was purchased in less than 2 years. 3) For the kerosene engine power tiller, breaks down occured every 36.8 hours of use, which is a higher value compared with diesel engine power tiller which break down every 42.8 hours of use. The 8HP kerosene engine power tiller showed higher frequency of break down compared with any other horse power tiller. 4) In October, the lowest frequency of break down was found with the value of once for every 51.5 hours of use, and it was followed by the frequency of break down in June. The more hours of use, the less breaks down was found. E. Repair place 1) 45.3% among total breaks down of power tiller was repaired by the owner, and 54.7% was repaired at repair shop. More power tiller were repaired at repair shop than by owner of power tiller. 2) The older the power tiller is, the higher percentage of repairing at the repair shop was found compared with the repairing by the owner. 3) Higher percentage of repairing by the owner was found for the diesel engine power tiller compared with the kerosene engine power tiller. It was 10 HP power tiller for the kerosene power tiller and 8 HP for the diesel engine power tiller. 4) 66.7% among total breaks down of steering device was repaired by the owner. It was the highest value compared with the percentage of repairing of any other parts of power tiller. The lowest percentage of repairing by owner was found for the attachments to the power tiller with the value of 26.5%. C. Cause of break down 1) Among the total breaks down of power tiller, 57.2% is caused by the old parts of power tiller with the value of 5.18 times break down a year and 34.7% was caused by the poor maintenance and over loading. 2) For the power tiller which was purchased in less than two years, more breaks down were caused by poor maintenance in comparison to the old parts of power tiller. 3) For the both 8-10 HP kerosene and diesel engine power tiller, the aspects of breaks down was almost the same. But for the 5 HP power tiller, more breaks down was caused by over loading in comparison to the old parts of power tiller. 4) For the cylinder system and traction device, most of the breaks down was caused by the old parts and for the fuel and ignition system, breaks down was caused mainly by the poor maintenance. D. Repair Cost 1) For each power tiller, repair cost was 34,509 won a year and it was 97 won for one hoar operation. 2) Repair cost of kerosene engine power tiller was 40,697 won a year, and it use 28,320 won for a diesel engine power tiller. 3) Average repair cost for one hour operation of kerosene engine power tiller was 103 won, and 86 won for a diesel engine power tiller. No differences were found between the horse power of engines. 4) Annual repair cost of cylinder system was 13,036 won which is the highest one compared with the repair cost of any other parts 362 won a year was required to repair the steering device, and it was the least among repair cost of parts. 5) Average cost for repairing the power tiller one time was 3,183 won. It was 10,598 won for a cylinder system and 1,006 won for a steering device of power tiller. E. Time requirement for repairing by owner. 1) Average time requirements for repairing the break down of a power tiller by owner himself was 8.36 hours, power tiller could not be used for operation for 93.58 hours a year due to the break down. 2) 21.3 hours were required for repairing by owner himself the break down of a power tiller which was more than 6 years old. This value is the highest one compared with the repairing time of power tiller which were purchased in different years. Due to the break down of the power tiller, it could not be used for operation annually 127.13 hours. 3) 10.66 hours were required for repairing by the owner himself a break down of a diesel engine power tiller and 6.48 hours for kerosene engine power tiller could not be used annually 99.14 hours for operation due to the break down and it was 88.67 hour for the diesel engine power tiller. 4) For both diesel and kerosene engine power tiller 8 HP power tiller required the least time for repairing by owner himself a break down compared with any other horse power tiller. It was 2.78 hours for kerosene engine power tiller and 8.25 hours fur diesel engine power tiller. 5) For the cylinder system of power tiller 32.02 hours were required for repairing a break down by the owner himself. Power tiller could not be used 39.30 hours a year due to the break down of the cylinder system.

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Relationship between the level of Sexual Contacts and Self-Esteem, Self-Assertiveness of Teenage Girls Who Have or Had Boyfriends (이성교제를 하는 십대여학생의 성접촉과 자아존중감.자기주장의 관계)

  • Lee, Sun-Kyoung
    • Women's Health Nursing
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    • v.7 no.2
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    • pp.212-228
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    • 2001
  • This is a cross-sectional descriptive correlation study that aimed to understand the relationship between the level of sexual contacts during the dates and psycho-social factors in teenage girls who have or had boyfriends. The purpose of this study was to describe the relationship between sexual contacts and self-esteem and self- assertiveness. The subjects of the study were 6,130 teenage girls who have or had boyfriends. They were selected convienently 12,733 teenage girls from 254 secondary schools located in 7 large cities and 9 provinces in Korea. A structured questionaire was used it included items one general characteristics, the levels of sexual contacts, self-esteem and self-assertiveness. Seven levels of sexual contacts were rated they were holding a hand, putting arms around each other's shoulders, kiss, french kiss, touching breast, petting genitalia, and sexual intercourse during the dates. Self-esteem and self-assertiveness were measured by the "Self-esteem scale" of Rogenberg (1971) and the questionaires developed by S. B. Chang et al(2000), respectively. The self-reported questionaires were collected from October 2, to October 28, 2000 and analyzed by using SPSS 10.0 Program. The data were analyzed by descriptive statistics, reliability, One-way ANOVA with Duncan method & Scheffe method. The results of the analysis were as follows. 1.An average Percentage of the respondents who have (46.1%) or had (53.9%) boyfriends was 48.1% (n=6,130) and the most common sexual contact during the dates was french kiss (26.7%, n=1,634). While 7.5%(458) of respondents had a sexual intercourse, 13.7%(842) of respondents didn't have any sexual contact during the dates. 2. Distribution of starting point of the first sexual contact demonstrates that 1,950 respondents (31.8%) held partner's hand at the first date and 1,367 respondents (22.3%) put arms around each other's shoulders at the 2nd or 3rd date. Sexual contacts such as kiss, french kiss, touching breast, petting genitalia, or sexual intercourse were experienced mostly at the later than the 10th date. However, surprisingly large number(1.7%) of respondents had genital contact and sexual intercourses at the first date. 3. The means of self-esteem and self-assertiveness socres of the respondents who have or had boyfriends are 27.43$({\pm}4.03)$ and 17.96$({\pm}2.55)$, respectively. The range of scores for self esteem was 10-40, 40 with most self esteem. The range of scores for self assertiveness was 7-21, 21 with most self assertiveness. 4. As sexual contacts proceeded, the means of self-esteem and self-assertiveness values decreased. In detail, the respondents having no or light sexual contacts (kiss, putting arms around each other's shoulder, holding a hand) had similar self-esteem values($p{\leq}0.05$). However, ones having relatively intensive sexual contacts (french kiss, touching breast) showed significantly lower self-esteem values($p{\leq}0.05$). Same trend has been obtained for self-assertiveness value. 5. The higher values of self-esteem and self-assertiveness values the respondents had, the later they started the moderate sexual contact (kiss, french kiss) during the dates. Interestingly, among the respondents having intensive sexual contacts (petting genitalia, sexual intercourse) during the dates, those who experienced the such contacts at the first date or later than 10th date have higher self-esteem and self-assertiveness values than one experienced the such contacts during the 2nd$\sim$9th dates, giving U-shape curve. 6. There was a significant relationship between self-esteem and self-assertiveness in girls who have or had boyfriends($P{\leq}.001$). In conclusion, the research shows that self-esteem and self-assertiveness values are significantly related with the sexual contacts of the teenage girls who have or had boyfriends. These results strongly suggest that proper sex education program for teenage girls should contain the program on improving the self-esteem and self-assertiveness. We believe that sex education program is the one of the best ways to prevent the unwanted sexual contacts and pregnancy of teenage girls.

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A Study on Switching Intention of Mobile Telecommunication Service User: Focused on Group Differences Based on Innovativeness (이동통신 서비스 이용자의 전환의도에 관한 연구: 개인 혁신성에 따른 집단 간의 차이를 중심으로)

  • Oh, Jong-Chul;Yoon, Sung-Joon
    • Journal of Global Scholars of Marketing Science
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    • v.19 no.1
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    • pp.9-21
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    • 2009
  • Recently, the researches to explain Switching Behavior through Theory of Planned Behavior have been discovered. Many researches say that System factors of mobile telecommunication service(MTS) is positively associated with Switching Intention. But There is no difference of system factors between mobile telecommunication services because of IT technique Development. Thus, this study investigated whether switching cost and alternative's attractiveness influence switching intention concerning mobile telecommunication service by adopting Theory of Planned Behavior (TPB) as an underlying theoretical premise. The study also attempted to determine the moderating effects of personal innovativeness on switching intention. For these purposes the author has developed several hypotheses as follows: H-1. The switching cost of different MTS is associated with the attitude of MTS which is using. H-2. The switching cost of different MTS is associated with the subjective norm of MTS which is using. H-3. The switching cost of different MTS is associated with the perceived behavior control of MTS which is using. H-4. The alternative's attractiveness of different MTS is associated with the attitude of MTS which is using. H-5. The alternative's attractiveness of different MTS is associated with the subjective norm of MTS which is using. H-6. The alternative's attractiveness of different MTS is associated with the perceived behavior control of MTS which is using. H-7. The switching cost of different MTS is associated with the switching intention. H-8. The alternative's attractiveness of different MTS is associated with the switching intention. H-9. The attitude of MTS is associated with the switching intention. H-10. The subjective norm of MTS is associated with the switching intention. H-11. The perceived behavior control of MTS is associated with the switching intention. H-12. The personal innovativeness has been a moderating effects to switching intention. Data has been collected from 403 respondents for this study using a questionnaire method. The survey for the actual analysis of the research was done and analyzed with the customers who have an experience of using Mobile telecommunication service and the samples were selected among the middle and high school students who live in Seoul area, the university students who live in Seoul, Gyeonggi and Chungcheng Provinces, and the ordinary workers who are working in Seoul and Gyeonggi Province. The survey was done for 23 days from March 28, 2008 through April 12, 2008. The positive analysis was done with SPSS 12.0K statistics package and visual PLS program using the analysis techniques of frequency analysis, reliability analysis, correlation analysis and factor analysis. In addition, structural equation modeling was conducted using AMOS 5.0. The data was analyzed by frequency analysis using SPSS 12.0 and structural equation modeling using AMOS 5.0. The result of the overall model analysis is as follows: Chi-Square=378.306, d.f.=107, p-value=0.0, GFI=.904, AGFI= 0.863, IFI= 0.939, NFI= 0.917, RMSEA= 0.079, TLI= 0.922. The results of the overall model analysis were coherent. The following study results were revealed: First, switching cost was related positively to attitude, subjective norm and perceived behavior control, three components of TPB. Second, alternative's attractiveness was related negatively to subjective norm but positively to perceived behavior control. Third, switching cost and attitude was related negatively to switching intention, while perceived behavior control was related positively to switching intention. Finally, the study found the moderating effects of personal innovativeness on switching intention. Based on the results, the study offers marketing strategic implications for mobile telecommunication service industry.

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Monitoring of Antimicrobial Resistant Bacteria from Animal Farm Environments in Korea (국내 축산 환경 중의 항생제 내성균 모니터링에 관한 연구)

  • Kwon, Young-Il;Kim, Tae-Woon;Kim, Hae-Yeong;Chang, Yun-Hee;Kwak, Hyo-Sun;Woo, Gun-Jo;Chung, Yun-Hee
    • Microbiology and Biotechnology Letters
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    • v.35 no.1
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    • pp.17-25
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    • 2007
  • The kinds and quantity of antimicrobial agents used for cattle (animal industry) may be considerable, suggesting the possibility that pathogenic bacteria which cannot be extirpated by the existing antimicrobial agents could appear. Ten cattle, pig and chicken farms, respectively, were randomly selected from 5 provinces in Korea and the samples were collected from excrement, manure, underground water, farmers' hands and the neishboring environment. h total of 299 samples were examined and 197 of Escherichia coli, 13 of Campylobacter jejun/coli, 223 of Enterococcus faecium/faecalis and 42 of Staphylococcus aureus isolates were collected. All isolates were screened for antimicrobial resistance: 69.4% of E. coli (137/197 strains), 78.6% of S. aureus (33/42 strains), and 82.1% of E. faecium/faecalis (183/223 strains) were resistant to one antimicrobial agent and all of C. jejuni/coli Isolates showed the resistance to one antimicrobial agent. Meanwhile, the multiple resistance ratio for more than 4 lines of antimicrobial agent was 19.2% of E. coli (38/197 strains), 11.9% of S. aureus (5/42 strains), 15.4% of C. jejuni/coli (2/13 strains) and 6.2% of E. faecium/faecalis (14/223 strains). The antimicrobial resistance ratio of bacteria isolated from the cattle farm showed lower than that of bacteria isolated from the pig or chicken farm, which might be related to the quantify of antimicrobial agents consumed. And one strain of vancomycin resistant E..faecium (VREF) were isolated from the excrement of chicken and stream, respectively. Generally, the ratio of VREF collected in animal farm environments is lower than that of VREF collected in medical environment.

Occurrence of Papaya ringspot virus Infecting Cucurbit Crops in Korea (박과작물에 발생하는 파파야원형반점바이러스의 발생 보고)

  • Jin, Tae-Seong;Kim, Sang-Mok;Ko, Sug-Ju;Lee, Su-Heon;Choi, Hong-Soo;Park, Jin-Woo;Cha, Byeong-Jin
    • The Korean Journal of Pesticide Science
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    • v.13 no.4
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    • pp.298-308
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    • 2009
  • A flexuous rod-shaped virus was isolated from Cucurbita pepo leaves showing as green mosaic and puckering symptoms at Anseong, Korea. Based on the biological analysis, electron microscopy, and reverse transcription-polymerase chain reaction (RT-PCR), the virus isolate was identified as Papaya ringspot virus type watermelon (PRSV-W). From biological analysis, the host range of PRSV-W was limited to the families Cucurbitaceae and Chenopodiaceae. Most susceptible cucurbit species, such as Cucumis lanatus, Cucumis sativus, Cucurbita pepo, and Citrullus lanatus, showed symptoms of green mosaic, malformation, puckering, and narrow laminae by infection with PRSV-W. The local lesion were showed on the inoculated leaves of both Chenopodium amaranticolor and C. quinoa. Field survey of PRSV, Watermelon mosaic virus (WMV) and Zucchini yellow mosaic virus (ZYMV), three major viruses infecting cucurbit, was done during 2001 to 2003 on 173 commercial cucurbit cultivating fields distributed over the three regions of Gyeonggi, Gyeongbuk and Jeonnam Provinces where cucurbits are grown in different environmental conditions and cropping patterns. Typical viral symptoms were observed from 107 cultivating fields, and all three kinds of potyviruses were detected from 206 samples out of the 235 samples using RT-PCR. Watermelon mosaic virus (WMV) and Zucchini yellow mosaic virus (ZYMV) are the most widely distributed viruses in outdoor and retarding-culture fields, at an infection rating of 48 and 33 percents, respectively. PRSV was detected from 12 percent of 235 samples. The nucleotide and amino acid sequences of coat proteins (CP) of eight PRSV isolates, collected from several areas including Anseong, were determined and sequenced heterogeneity among the isolates was performed. The CP gene of PRSV showed 88.6~97.3 percent homology in nucleotide sequences and 95.1~99.3 percent homology in amino acid sequences with other PRSV isolates worldwide. The phylogenetic analysis indicated that the Korean PRSV isolates belong to the southern-east Asian cluster.