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Studios on the Metagonimus fluke in the Daecheong Reservoir and the upper stream of Geum River, Borea (대청호 및 그 상류의 Metagonimus 흡충에 관한 연구)

  • 김종환;김남만
    • Parasites, Hosts and Diseases
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    • v.25 no.1
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    • pp.69-82
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    • 1987
  • The prevalences of the cuke belonging to genus Metagonimus hove been reported along the upper stream of inhabitants by several workers since 1980, however the taxonomical problems of the fluke was not yet settled. The larval flukes; cercaria and metacercaria as well as their intermediate hosts, and adult were studied in order to identify the Mepagonimus in the areas. The results obtained are summarized as follows: 1. The snails, Semisulcospira globus were collected (rom the three different localities along the upper stream of the River. The cercariae were found from 125(7.2%) out of 1,730 snails by natural emerging method, and were identified into 5 species including Metagenimus sp. (3.7%), Pseudexorchis major(1.4%), Cercaria nipponensis (0.9%), Cercaria incerpa(0.6%), and Cercaria yoshidae(0.6%). Cercariae of Metagonimus species had four to dye oral spines on its anterior of the first line. 2. The cercariae of Metagonimus were experimentally exposed to goldfish. nfection rate was 22.9% out of 105 goldfish, and the encysted metacercariae were found in fins(86.7%) and on scales (13.7%) of the fishes, but not in their muscle, head or visceral organs. 3. Seven species of ask were caught in the Daecheong Reservoir and the upper stream. Infestations with metacercaria of Metagonimus were found 100% in Opsariichtys widens and the parasitized numbers of the metacercariae were observed from 250 to 2,400 per fish. In the upper stream, Zacco termmincki, Z. platypus and Pseudogobio esocinus were infected 100% with the metacercaria, on the other hand, the fishes caught in the reservoir showed the lower infestation rates, and a few metacercariae found in the fishes Carassius carassius and Cyprinus carpio in the reservoir and the stream. The majority of metacercariae was detected only on the scales of fishes. 4. In order to know the infectivity and the distribution patterns in the intestine of hosts, rats and dogs were infected with the metacercariae obtained from O. bidens and Z. platypus. In addition the metacercariae obtained from Z. temmincki, P. esocinus and goldfish were given to the rats. The recovery rates of the worms in the small intestine of dogs were higher (63.3~65.8%) than those of the rats (3.5~31.6%). The flukes were found mostly in the middle and the lower part of small intestine of the rats and the dogs, but no worm was collected in the upper part of the intestine of rats. 5. The sixte of adult flukes varied by the hosts. In the adult cukes, oral sucker was smaller than ventral sucker, and the right and left testes were located diagonally, the uterine tubules circled around the upper left testis. The average egg sixte was $29.1{\times}1.7{\mu\textrm{m}}$. According to the above results, the cukes belonging to genus Metagonimus distributed along the Geum River was concluded to be identical with Miyata type of M. yokogawai as that Saito had proposed.

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Study on the Usefulness of Using Anterior and Posterior Views for Calculation of Total Relative Uptake Ratio in 99mTc-DMSA Renal Scan (99mTc-DMSA 검사에서 상대 신섭취율 산출 시 양면상 촬영의 유용성에 대한 고찰)

  • Kim, Joo-Yeon;Lee, Han-Wool;Kwon, O-Jun;Kim, Jung-Yul;Park, Min-Soo;Cho, Seok-Won;Kang, Chun-Goo;Kim, Jae-Sam
    • The Korean Journal of Nuclear Medicine Technology
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    • v.19 no.1
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    • pp.37-43
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    • 2015
  • Purpose $^{99m}Tc-DMSA$ renal scintigraphy serves as location, size and shape of kidney, so it has been used for diagnosis and passage observation after the operation or treatment. There are 3 methods of calculating the relative renal uptake ratio such as geometric mean of the counts from the anterior and posterior views, arithmetical mean from the only posterior view and posterior view which applied the renal depths. In this study, we seek to correlation between the change of total relative uptake ratio according to different inspection methods of obtaining the renal count rate. Materials and Methods The phantom experiments proceeded 5 times depending on each renal depth with the kidney phantom and tissue equivalent materials. In the clinical research, we investigated 36 adult patients who had visited our hospital from february to october, 2014 and received $^{99m}Tc-DMSA$ renal scan. The equipment was used as a gamma camera named INFINIA (General Electric Healthcare, milwaukee, USA) and we drew the region of interests through semiautomatic method by using Xeleris Ver. 2.1220 of GE. In addition, we obtained the lateral view of kidney to measure the renal depth of each patient. Then the results were compared with 3 methods of calculating relative renal uptake ratio. Results The phantom studies show when the difference between the left ant right kidney depth were less than 1 cm, there were no statistically significant difference among values calculated through anterior and posterior views and only posterior view (P>0.05), while the excess of 1cm, the results showed a statistically significant change in the value (P<0.05). In case of clinical research, the correlation between total relative uptake ratio by obtaining both sides of image and posterior view applied the kidney depth (r=0.999) was higher than by obtaining only posterior view and applying the kidney depth to one side image (r=0.988). Conclusion This study has found that, the difference of calculating total relative uptake ratio compared with obtaining anterior and posterior views and only posterior view. In order to reduce the error, we recommend the method of obtaining anterior and posterior views and is considered to be useful, particularly the patients have similar uptake ratio of left and right kidney and difficulties of measurements of kidney depth.

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Feasibility Study of Wetland-pond Systems for Water Quality Improvement and Agricultural Reuse (습지-연못 연계시스템에 의한 수질개선과 농업적 재이용 타당성 분석)

  • Jang, Jae-Ho;Jung, Kwang-Wook;Ham, Jong-Hwa;Yoon, Chun-Gyeong
    • Korean Journal of Ecology and Environment
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    • v.37 no.3 s.108
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    • pp.344-354
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    • 2004
  • A pilot study was performed from September 2000 to April 2004 to examine the feasibility of the wetland-pond system for the agricultural reuse of reclaimed water. The wetland system was a subsurface flow type, with a hydraulic residence time of 3.5 days, and the subsequent pond was 8 $m^3$ in volume (2 m ${\times}$ 2 m ${\times}$ 2 m) and operated with intermittent-discharge and continuous flow types. The wetland system was effective in treating the sewage; median removal efficiencies of $BOD_5$ and TSS were above 70.0%, with mean effluent concentrations of 27.1 and 16.8 mg $L^{-1}$, respectively, for these constituents. However, they did often exceed the effluent water quality standards of 20 mg $L^{-1}$. Removal of T-N and T-P was relatively less effective and mean effluent concentrations were approximately 103.2 and 7.2 mg $L^{-1}$, respectively. The wetland system demonstrated high removal rate (92 ${\sim}$ 90%) of microorganisms, but effluent concentrations were in the range of 300 ${\sim}$ 16,000 MPN 100 $mL^{-1}$ which is still high for agricultural reuse. The subsequent pond system provided further treatment of the wetland effluent, and especially additional microorganisms removal in addition to wetland-pond system could reduce the mean concentration to 1,000 MPN 100 $mL^{-1}$ from about $10^5$ MPN 100 $mL^{-1}$ of wetland influent. Other parameters in the pond system showed seasonal variation, and the upper layer of the pond water column became remarkably clear immediately after ice melt. Overall, the wetland system was found to be adequate for treating sewage with stable removal efficiency, and the subsequent pond was effective for further polishing. This study concerned agricultural reuse of reclaimed water using natural systems. Considering stable performance and effective removal of bacterial indicators as well as other water quality parameters, low maintenance, and cost-effectiveness, wetland- pond system was thought to be an effective and feasible alternative for agricultural reuse of reclaimed water in rural area.

Community Distribution on Mountain Forest Vegetation of the Geumsusan and Doraksan Area in the Worak National Park, Korea (월악산국립공원 금수산 및 도락산 일대 삼림식생의 군락분포에 관한 연구)

  • Lee, Jung-Yun;Oh, Jang-Geun;Jung, Se-Hoon;Kim, Ha-Song
    • Korean Journal of Ecology and Environment
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    • v.48 no.2
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    • pp.129-138
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    • 2015
  • Forest vegetation of Geumsusan (1,016.0 m) and Doraksan (964.4 m) in Woraksan National Park is classified into mountain forest vegetation. Mountain forest vegetation is subdivided into deciduous broad-leaved forest, mountain valley forest, coniferous forest, riparian forest, afforestation and other vegetation. Including 77 communities of mountain forest vegetation and 5 communities of other vegetation, the total of 82 communities were researched; mountain forest vegetation classified by physiognomy classification are 37 communities deciduous broad-leaved forest, 16 communities of mountain valley forest, 8 communities of coniferous forests, 1 community of riparian forest, 15 afforestation and 5 other vegetation. As for the distribution rate for surveyed main communities, Quercus variabilis and Quercus mongolica communities account for 33.031 percent of deciduous broadleaved forest, Cornus controversa community takes up 29.142 percent of mountain valley forest, Pinus densiflora community holds 64.477 percent of mountain coniferous forest holds. In conclusion, minority species consisting of Quercus variabilis, Quercus mongolica, Pinus densiflora, Quercus serrata and Cornus controversa are distributed as dominant species of the uppermost part in a forest vegetation region in Woraksan National Park. In addition, because of vegetation succession and climate factors, numerous colonies formed by the two species are expected to be replaced by Quercus variabilis, Quercus mongolica, Cornus controversa and Fraxinus mandshurica which are climax species in the area.

An Analysis of Epidemiological Investigation Reports Regarding to Pathogenic E. coli Outbreaks in Korea from 2009 to 2010 (최근 2년간(2009-2010) 우리나라 병원성 대장균 식중독 역학조사 보고서 분석)

  • Lee, Jong-Kyung;Park, In-Hee;Yoon, Kisun;Kim, Hyun Jung;Cho, Joon-Il;Lee, Soon-Ho;Hwang, In-Gyun
    • Journal of Food Hygiene and Safety
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    • v.27 no.4
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    • pp.366-374
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    • 2012
  • Recently pathogenic E. coli is one of the main foodborne pathogens resulting in many patients in Korea. To understand the characteristics of pathogenic E. coli outbreaks in Korea, the epidemiological investigation reports of pathogenic E. coli outbreak in 2009 (41 reports) and in 2010 (27 reports) were collected in the web site of the Korea Centers for Disease Control and Prevention, reviewed and analysed in this study. The main places of the pathogenic E. coli outbreaks were food catering service area (64.8%) and restaurants (25.0%). The main type of the pathogens were EPEC (44.7%) and ETEC (34.2%). EAEC and EHEC was responsible for 10.5 and 9.2%, respectively. Eight of 68 outbreak cases were caused by more than 2 types of pathogenic E. coli which implicates the complicated contamination pathways of pathogenic E. coli. The incidence rate of pathogenic E. coli was $33.6{\pm}30.5%$ and the main symptoms were diarrhea, stomach ache, nausea, vomiting, and fever etc. The two identified food sources were identified as frozen hamburger pattie and squid-vegetable mixture. To improve the food source identification by epidemiological investigation, food poisoning notification to the agency should not be delayed, whole food items attributed the outbreak should be collected and detection method of the various pathogenic E. coli in food has to be improved. In conclusion, the characteristics between the EHEC outbreaks in the western countries and the EPEC or ETEC outbreaks in Korea needs to be distinguished to prepare food safety management plan. In addition, the development of the trace back system to find the contamination pathway with the improved detection method in food and systemic and cooperative support by the related agencies are necessary.

Virulence Profile and Antimicrobial Resistance of Escherichia coli from Flies Captured from Agricultural Environment (농업환경에 서식하는 파리에서 분리된 E. coli의 병원성 유전자 및 항생제 내성 조사)

  • Yun, Bohyun;Jang, Youn Jung;Kim, Yeon Rok;Kim, Hwang-Yong;Kim, Won-Il;Han, Sanghyun;Kim, Se-Ri;Ryu, Jae-Gee;Kim, Hyun Ju
    • Journal of Food Hygiene and Safety
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    • v.32 no.2
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    • pp.147-153
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    • 2017
  • The purpose of this study was to isolate Escherichia coli from flies and to assess pathogenic genes and antibiotic resistance of the isolates. A total of 188 flies were captured in agricultural environment including fruits farms (n = 19), fermented soybean farms (n = 9), municipal waste (n = 46), livestock farms (n = 66), slaughterhouses (n = 38), and manure ground (n = 10). E. coli isolates of captured flies were tested for pathogenic gene and antibiotic resistance using PCR methods and VITEK2 systems. As a result, E. coli from 63% (119/188) of the captured flies has been detected, and the detection rate of E. coli was the highest (89%, 31/34) in flies captured at particular slaughterhouse. Of the 34 isolates, 94% (32/34) were pathogenic gene (ST gene) positive. Twenty-six percent (31/119) of the E. coli isolates were observed being resistant to one or more antibiotics. Markedly, one of E. coli isolates from Livestock farms was resistant to 7 antibiotics including ampicillin, ampicillin/sulbactam, cefazolin, cefotaxime, gentamicin, levofloxacin, and trimethoprim/sulfamethoxazole. In addition, it was ESBL positive. The results of the present study may suggest a risk of transmission of pathogenic and antimicrobial resistant bacteria from flies to livestock environment Therefore, it may need to prevent introducing flies into the agricultural production environment for safe food production.

Reduction of dissolved hydrogen sulfide and mortality of white leg shrimp, Litopenaeus vannamei by Bacillus spp. microorganisms (Bacillus속 미생물의 용존황화수소 저감효과와 흰다리새우(Litopenaeus vannamei)에의 영향)

  • Choi, Jun-Ho;Lee, Ji-Hoon;Park, Jung-Jin;Lee, Min-Sun;Bae, Jun-Sung;Shin, Dong-Hun;Park, Kwan Ha
    • Journal of fish pathology
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    • v.31 no.1
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    • pp.41-48
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    • 2018
  • The utility of Bacillus spp. organisms for reduction of dissolved hydrogen sulfide ($H_2S$) in white leg shrimp (Litopenaeus vannamei) culture was tested with different combinations of Bacillus spp. microorganisms: combination A (B. subtilis + B. licheniformis); combination B (B. licheniformis + B. amyloliquefaciens); combination C (B. subtilis + B. licheniformis + B. amyloliquefaciens). Of these 3 combinations, C was effective in few hours after addition whereas B needed longer time to be effective. The $H_2S-reducing$ effect of combination C was dependent on the amount of microorganisms added to $H_2S-containing$ test solution. Exposure of white leg shrimp to $H_2S$ at 8 mg/L for 7 days led to survival of 80% and 1 mg/L for 14 days it was 82.5%. The survival rate was 97.5% when combination C was simultaneously added to shrimp tanks during $H_2S$ exposure at 1 mg/L for 14 days. It was demonstrated that combination C microorganisms (B. subtilis + B. licheniformis + B. amyloliquefaciens) can reduce dissolved $H_2S$ concentrations, and this effect can be utilized to protect white leg shrimp from $H_2S$ toxicity.

Effects of Dietary Sources Containing ω-3 Fatty Acids on the Fatty Acid Composition of Meats in Korean Native Chickens (오메가 3계열 지방산을 함유하는 사료의 급여가 육용 토종닭 계육 내 지방산 조성에 미치는 영향 탐색)

  • Oh, Sung-Taek;Jhun, Heung-Kyu;Park, Jung-Min;Kim, Jin-Man;Kang, Chang-Won;An, Byoung-Ki
    • Food Science of Animal Resources
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    • v.32 no.4
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    • pp.476-482
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    • 2012
  • Estimations were made of oxidative susceptibility and fatty acid composition of edible meats of native chickens fed various dietary sources containing ${\omega}-3$ polyunsaturated fatty acids (PUFA). A total of 240 Korean native chickens were divided into 4 groups, placed into 3 replicates per group, and were fed a commercial diet (Control) or one of the three experimental diets containing 10% perilla meal (PM group), 10% perilla meal-5% full fat flaxseed (PM+FS group), or 10% perilla meal-5% full fat flaxseed-1% fish oil (PM+FS+FO group) for 20 days. Final body weight, weight gain, feed intake, and feed conversion rate among the groups were not significantly different. Dietary treatments did not affect the relative weights of liver, abdominal fat, and breast muscle. The leg weight was increased from the feeding of ${\omega}-3$ PUFA sources. The TBA reactive substance in the edible meat was not different with the dietary treatments. The total ${\omega}-3$ PUFA in chickens that were fed diets containing ${\omega}-3$ PUFA sources increased compared to that of the control. The level of longer chain ${\omega}-3$ PUFAs, such as C20:5 ${\omega}3$ and C22:6 ${\omega}3$ in the PM+FS+FO group, was much higher than that of the others. The addition of local ingredients, such as perilla meal with conventional sources, could be used to obtain value-enhanced meat by enhancing ${\omega}-3$ PUFA.

Belief factors associated with breastfeeding intentions of single women: Based on the theory of planned behavior (계획적 행동이론을 적용한 미혼여성의 모유수유 의도와 관련된 신념요인)

  • Jang, Min Kyung;Lee, Seung-Min;Khil, Jin
    • Journal of Nutrition and Health
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    • v.50 no.3
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    • pp.284-293
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    • 2017
  • Purpose: This study was conducted to examine the behavioral intentions of breastfeeding in single women using the theory of planned behavior. Methods: The questionnaires were distributed to 350 single women in her 20~30s, and 316 respondents were analyzed by descriptive statistics, Spearman's correlation, and multiple regression analysis. Results: The subjects showed strong intentions and favorable attitudes toward breastfeeding. The subjects were more favorably influenced by their mothers, siblings, friends, and coworkers who previously experienced breastfeeding than ones with no breastfeeding experiences. There were significant correlations between breastfeeding intention and attitudes (r = 0.321, p < 0.0001), subjective norms (r = 0.434, p < 0.0001), and perceived control (r = 0.307, p < 0.0001). However, regression analysis with two different age groups revealed that subjective norms (p < 0.0001) and perceived control (p < 0.001) contributed to the model of explaining breastfeeding intentions in subjects who were 25 years old or younger, whereas attitudes did not. In addition, subjects who were more than 25 years old showed that attitudes (p < 0.003) and subjective norms (p = 0.002) contributed to the model of explaining breastfeeding intentions while perceived control (p < 0.070) showed less contribution. Conclusion: These results suggest that the theory of planned behavior can be a useful tool to increase the rate of breastfeeding intentions in single women when designing educational materials, which requires consideration of age differences.

Investigations on the Adsorption Characteristics of $SO_2$ Gas on Fixed Bed Manganese Nodule Column (고정(固定) 흡착층(吸着層)에서 망간단괴(團塊)의 $SO_2$ 가스 흡착(吸着) 특성(特性)에 관한 연구(硏究))

  • Baek, Mi-Hwa;Kim, Dong-Su;Jung, Sun-Hee;Park, Kyoung-Ho
    • Resources Recycling
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    • v.15 no.4 s.72
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    • pp.3-12
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    • 2006
  • The feasibility for the employment of manganese nodule as an adsorbent for $SO_{2}$ gas has been investigated. The specific surface area of manganese nodule particle, which used in the experiments, was ca. $221.5m^{2}/g$ and the content of sulfur in manganese nodule was observed to significantly increase after $SO_{2}$ was adsorbed on it. The EPMA for the distilled water-washed and methanol-washed manganese nodule particle after $SO_{2}$ adsorption showed that its sulfur content was slightly decreased to 14.7% and 13.1% respectively, from 15.4% before washing. The XRD analysis of manganese nodule showed that todorokite and birnessite, which are manganese oxides, and quartz and anorthite were the major mineralogical components and weak $MnSO_{4}$ peaks were detected after $SO_{2}$ was adsorbed on manganese nodule. For an comparative investigation, limestone was also tested as an adsorbent for $SO_{2}$, however, no peaks for $CaSO_{4}$ were found by XRD analysis after the adsorption of $SO_{2}$. As the size of adsorbent increased, time for breakthrough was decreased and the adsorbed amount of $SO_{2}$ was also diminished. The $SO_{2}$ adsorption was hindered when its flow rate became high and the adsorption capacity of manganese nodule was observed to be superior to that of limestone. In addition, the mixture of manganese nodule and limestone did not show an increase in the adsorption of $SO_{2}$. Finally, as the temperature was raised, the adsorbed amount of adsorbate on manganese nodule was found to be decreased.